Related Art [0002] Pick and place techniques are often used to assemble electronic devices. Such techniques involve a manipulator, such as a robot arm, to remove integrated circuit (IC) dies from a wafer and place them into a die carrier. The dies are subsequently mounted onto a substrate with other electronic components, such as antennas, capacitors, resistors, and inductors to form an electronic device.

[0003] Pick and place techniques involve complex robotic components and control systems that handle only one die at a time. This has a drawback of limiting throughput volume. Furthermore, pick and place techniques have limited placement accuracy, and have a minimum die size requirement.

[0004] One type of electronic device that may be assembled using pick and place techniques is an RFID"tag."An RFID tag may be affixed to an item whose presence is to be detected and/or monitored. The presence of an RFID tag, and therefore the presence of the item to which the tag is affixed, may be checked and monitored by devices known as"readers." [0005] As market demand increases for products such as RFID tags, and as die sizes shrink, high assembly throughput rates for very small die, and low production costs are crucial in providing commercially-viable products.

Accordingly, what is needed is a method and apparatus for high volume assembly of electronic devices, such as RFID tags, that overcomes these limitations.

SUMMARY OF THE INVENTION [0006] The present invention is directed to methods, systems, and apparatuses for producing one or more electronic devices, such as RFID tags, that each include a die having one or more electrically conductive contact pads that provide electrical connections to related electronics on a substrate.

[0007] According to the present invention, electronic devices are formed at much greater rates than conventionally possible. In one aspect, large quantities of dies can be transferred directly from a wafer to corresponding substrates of a web of substrates. In another aspect, large quantities of dies can be transferred from a support surface to corresponding substrates of a web of substrates. In another aspect, large quantities of dies can be transferred from a wafer or support surface to an intermediate surface, such as a die plate.

The die plate may have cells formed in a surface thereof in which the dies reside. Otherwise, the dies can reside on a surface of the die plate. The dies of the die plate can then be transferred to corresponding substrates of a web of substrates.

[0008] In an aspect of the present invention, methods, systems, and apparatuses for transfer of dies using the die plate are described herein. The die plate has a planar body. The body has a plurality of holes therethrough.

[0009] In an aspect, A punch plate, punch roller or cylinder, or expandable material can be used to transfer dies from the die plate to substrates.

[0010] Large quantities of dies can be transferred. For example, 10s, 100s, 1000s, or more dies, or even all dies of a wafer, support surface, or die plate, can be simultaneously transferred to corresponding substrates of a web.

[0011] In an aspect of the present invention, an area of a semiconductor wafer is expanded, an enhancing die transfer capability. A wafer is attached to a support structure. The wafer is separated on the support structure into a plurality of dies. An area of the support structure is increased to increase a space between adjacent dies of the plurality of dies. Dies may be transferred from the expanded support structure.

[0012] In one aspect, dies may be transferred between surfaces in a"pads up" orientation. When dies are transferred to a substrate in a'pads up" orientation, related electronics can be printed or otherwise formed to couple contact pads of the die to related electronics of the tag substrate.

[0013] In an alternative aspect, the dies may be transferred between surfaces in a"pads down"orientation. When dies are transferred to a substrate in a "pads down"orientation, related electronics can be pre-printed or otherwise pre-deposited on the tag substrates.

[0014] These and other advantages and features will become readily apparent in view of the following detailed description of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES [0015] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention.

[0016] FIGS. 1A shows a block diagram of an exemplary RFID tag, according to an embodiment of the present invention.

[0017] FIGS. 1B and 1C show detailed views of exemplary RFID tags, according to embodiments of the present invention.

[0018] FIGS. 2A and 2B show plan and side views of an exemplary die, respectively.

[0019] FIGS. 2C and 2D show portions of a substrate with a die attached thereto, according to example embodiments of the present invention.

[0020] FIG. 3 is a flowchart illustrating a tag assembly process, according to embodiments of the present invention.

[0021] FIGS. 4A and 4B are plan and side views of a wafer having multiple dies affixed to a support surface, respectively.

[0022] FIG. 5 is a view of a wafer having separated dies affixed to a support surface.

[0023] FIG. 6 shows a wafer that has been separated on a support surface being expanded in all directions, according to an embodiment of the present invention.

[0024] FIGs. 7A-7C show example steps related to a process for expanding a wafer, according to embodiments of the present invention.

[0025] FIG. 8 shows a tag assembly system, according to an example embodiment of the present invention.

[0026] FIG. 9 shows a flowchart providing steps for authenticating tags, according to embodiments of the present invention.

[0027] FIG. 10 shows a system diagram illustrating example options for transfer of dies from wafers to substrates, according to embodiments of the present invention.

[0028] FIGS. 11 and 12 show flowcharts providing steps for transferring dies from a first surface to a second surface, according to embodiments of the present invention.

[0029] FIGs. 13A and 13B show plan and cross-sectional views, respectively, of an example die receptacle structure, according to an embodiment of the present invention.

[0030] FIG. 14 shows a perspective view of a die receptacle structure, according to an example embodiment of the present invention.

[0031] FIG. 15 shows a perspective view showing a plurality of dies attached to a support structure being aligned over a die receptacle structure, according to an embodiment of the present invention.

[0032] FIG. 16 shows a perspective view of a die receptacle structure, with each cell filled with a corresponding die, according to an example embodiment of the present invention.

[0033] FIGs. 17A-17D show various views of a portion of a die receptacle structure, according to example embodiments of the present invention.

[0034] FIGs. 18A and 18B show perspective and bottom views, respectively, of a single cell of a die receptacle structure, according to embodiments of the present invention.

[0035] FIG. 19 shows an example vacuum assisted die transfer system, according to an example embodiment of the present invention.

[0036] FIG. 20 shows a flowchart providing example steps for vacuum assisted transfer of dies from a wafer into a die receptacle structure, according to embodiments of the present invention.

[0037] FIGs. 21-27 show example implementations of the steps of the flowchart of FIG. 20, according to embodiments of the present invention.

[0038] FIG. 28 shows a flowchart providing example steps for transferring dies from a support structure to a die receptacle structure, according to embodiments of the present invention.

[0039] FIGs. 29-31 show example implementations of the steps of the flowchart of FIG. 28, according to embodiments of the present invention.

[0040] FIG. 32 shows a flowchart providing example steps for transferring dies from a support structure to a die receptacle structure, according to embodiments of the present invention.

[0041] FIGs. 33-35 show example implementations of the steps of the flowchart of FIG. 32, according to embodiments of the present invention.

[0042] FIG. 36 shows a perspective view of an example die plate, according to an example embodiment of the present invention.

[0043] FIG. 37 shows an example schematic showing multiple views of an example die plate, according to an embodiment of the present invention.

[0044] FIG. 38 shows a perspective view of a portion of a surface of a die plate, according to an embodiment of the present invention.

[0045] FIG. 39 shows a flowchart providing example steps for transferring dies from a support structure to a die plate, according to embodiments of the present invention.

[0046] FIGs. 40-42 show example implementations of the steps of the flowchart of FIG. 39, according to embodiments of the present invention.

[0047] FIG. 43 shows a flowchart providing example steps for transferring dies from a wafer to a die plate, according to embodiments of the present invention.

[0048] FIGs. 44-46 show example implementations of the steps of the flowchart of FIG. 43, according to embodiments of the present invention.

[0049] FIG. 47 shows a pin plate, according to an example embodiment of the present invention.

[0050] FIGS. 48 and 49 show schematics providing multiple example views of a pin plate, according to example embodiments of the present invention.

[0051] FIG. 50 shows a flowchart providing example steps for transferring dies from a die receptacle structure to substrates of a web, according to embodiments of the present invention.

[0052] FIGs. 51-57 show example implementations of the steps of the flowchart of FIG. 50, according to embodiments of the present invention.

[0053] FIGS. 58 and 59 show various substrate arrays, and corresponding pin plates, according to example embodiments of the present invention.

[0054] FIGs. 60 and 61 show various substrates arrays that require pin plates of various sizes, according to further embodiments of the present invention.

[0055] FIGS. 62 and 63 show schematics providing multiple views of a chip assembly fixture having four die transfer heads, according to an example embodiment of the present invention.

[0056] FIGs. 64A, 64B, 65A, and 65B show views of a pin of a pin plate inserted in a hole of a die receptacle structure, and a die residing in a cell of the die receptacle structure, according to an example embodiment of the present invention.

[0057] FIG. 66 illustrates carousels used in a multi-head tag assembly system, according to embodiments of the present invention.

[0058] FIGS. 67-107 relate to various multi-head die transfer configurations, showing webs, substrate arrays, and corresponding pin plates, according to example embodiments of the present invention.

[0059] FIGS. 108a and 108b show some example geometric shapes for substrate arrays on a web and corresponding pin plates, according to the embodiments of the present invention.

[0060] FIG. 109 shows example die transfer rates for the various geometric substrate patterns shown in FIGS. 108a and 108b, according to embodiments of the present invention.

[0061] FIG. 110 shows an enlarged view of an example geometric substrate array pattern, according to an embodiment of the present invention.

[0062] FIGS. 111A and 111B show the geometric substrate array pattern of FIG. 110 used in a repeating, interlocked coverage pattern to cover all substrates in a web for die transfer, according to an embodiment of the present invention.

[0063] FIG. 112 shows another geometric substrate array pattern, according to an example embodiment of the present invention.

[0064] FIGS. 113A and 113B show webs having the geometric substrate array pattern of FIG. 112 used in an interlocking substrate coverage pattern, according to example embodiments of the present invention.

[0065] FIG. 114 shows another geometric substrate array pattern, according to an example embodiment of the present invention.

[0066] FIGS. 115A and 115B show webs having the geometric substrate array pattern of FIG. 114 used in an interlocking substrate coverage pattern, according to example embodiments of the present invention.

[0067] FIG. 116 shows another geometric substrate array pattern, according to an example embodiment of the present invention.

[0068] FIGS. 117A and 117B show webs having the geometric substrate array pattern of FIG. 116 used in an interlocking substrate coverage pattern, according to example embodiments of the present invention.

[0069] FIG. 118 shows another geometric substrate array pattern, according to an example embodiment of the present invention.

[0070] FIGS. 119A and 119B show webs having the geometric substrate array pattern of FIG. 118 used in an interlocking substrate coverage pattern, according to example embodiments of the present invention.

[0071] FIG. 120 shows another geometric substrate array pattern, according to an example embodiment of the present invention.

[0072] FIGS. 121A and 121B show webs having the geometric substrate array pattern of FIG. 120 used in an interlocking substrate coverage pattern, according to example embodiments of the present invention.

[00731 FIGS. 122 and 123 show further geometric substrate array patterns, according to example embodiments of the present invention.

[0074] FIG. 124 shows a flowchart providing example steps for designing a system for assembling RFID tags for a tag population, according to embodiments of the present invention.

[0075] FIG. 125 shows a flowchart providing example steps for transferring dies using an expandable material, according to embodiments of the present invention.

[0076] FIGS. 126-129 show example implementations of the steps of the flowchart of FIG. 126, according to embodiments of the present invention.

[0077] FIG. 130 shows a flowchart providing example steps for transferring dies directly from a support structure to a substrate, according to embodiments of the present invention [0078] FIGS. 131-135 show example implementations of the steps of the flowchart of FIG. 130, according to embodiments of the present invention.

[0079] FIG. 136 shows an example tagged optical disc, according to an embodiment of the present invention. l0080] FIG. 137 shows a flowchart providing example steps for manufacturing a tagged optical disc, according to embodiments of the present invention.

[0081] FIG. 138 shows metal being deposited onto a disc substrate having an example disc hub thereon to form metal connections, according to an embodiment of the present invention.

[0082] FIGS. 139A-139C show views of an example disc hub, according to embodiment of the present invention.

[0083] FIG. 139D shows an example interposer, according to an embodiment of the present invention.

[0084] FIGS. 140A-140C show views of an example disc hub, according to embodiment of the present invention.

[0085] FIG. 141 shows an example interposer, according to an embodiment of the present invention.

[0086] FIGS. 142A-142C show example tagged optical discs, according to embodiments of the present invention.

[0087] FIGS. 143-145 relate to an example antenna and web configuration, according to an example embodiment of the present invention.

[0088] FIGS. 146-148 relate to another example antenna and web configuration, according to an example embodiment of the present invention.

[0089] FIGS. 149 and 150 relate to another example antenna and web configuration, according to an example embodiment of the present invention.

[0090] FIG. 151 shows an example antenna interposer, according to an embodiment of the present invention.

[0091] FIG. 152 shows an example wafer having 48 dies, with identification numbers 1-48, according to embodiments of the present invention.

[0092] FIG. 153 shows an exemplary portion of a substrate web having dies from the wafer of FIG. 152 attached thereto, according to example embodiments of the present invention.

[0093] FIG. 154 shows an exemplary system having a positive pressure source and a vacuum/suction source, according to an example embodiment of the present invention.

[0094] FIG. 155 shows a cylindrical pin plate, according to example embodiments of the present invention.

[0095] FIG. 156 shows an example of a device assembly system, according to an example embodiment of the present invention.

[0096] FIG. 157 shows a flowchart providing example steps for assembling a plurality of devices in parallel, according to embodiments of the present invention.

[0097] FIG. 158 shows a flowchart providing example steps for applying adhesive to plurality of devices in parallel, according to embodiments of the present invention.

[0098] FIGs. 159a and 159b show a portion of an exemplary pin plate having removable pins and exemplary pins, according to example embodiments of the present invention.

[0099] FIG. 160 shows a flowchart of a method for recovering untransferred dies using a die receptacle structure, according to embodiments of the present invention.

[0100] FIG. 161 shows a exemplary wafer having a plurality of dies remaining after the transfer step is completed.

[0101] FIGS. 162A and 162B show views of a singulated wafer attached to support structure, which is held in a wafer frame, according to an embodiment of the present invention.

[0102] FIG. 163A shows a wafer frame that includes multiple wafer frame segments, holding a support structure attaching a plurality of dies, according to an example embodiment of the present invention.

[0103] FIG. 163B shows the wafer frame of FIG. 163A being expanded, according to an example embodiment of the present invention.

[0104] FIG. 164A shows dies of a singulated wafer attached to a support structure, in an unexpanded state.

[0105] FIG. 164B shows the support structure of FIG. 164A being radially stretched/expanded, to increase an area of the support structure, according to an example embodiment of the present invention.

[0106] FIG. 164C shows a die frame attached to the expanded support structure of FIG. 164B, according to an example embodiment of the present invention.

[0107] FIG. 165 shows a cross-sectional view of an expanded support structure that attaches dies of a singulated wafer, according to an example embodiment of the present invention.

[0108] FIG. 166 shows a die frame formed around the dies attached to the expanded support structure of FIG. 165, according to an example embodiment of the present invention.

[0109] FIG. 167 shows a support layer formed on the expanded support structure of FIG. 165, according to an example embodiment of the present invention.

[0110] FIG. 168 shows a support layer formed on the dies attached to the expanded wafer of FIG. 165, according to an example embodiment of the present invention.

[0111] FIG. 169 shows the expanded support structure of FIG. 165 attached to a die plate, for transfer of dies, according to an example embodiment of the present invention.

[0112] FIG. 170 shows an example system for expanding a wafer, and transferring dies from the expanded wafer, according to an embodiment of the present invention.

[0113] FIGS. 171-177 show various views of a transfer of dies to a die plate, and subsequently to one or more substrates, according to embodiments of the present invention.

[0114] FIG. 178 shows a flowchart providing steps for transferring dies, according to embodiments of the present invention.

[0115] The present invention will now be described with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements.

The drawing in which an element first appears is indicated by the leftmost digit (s) in the reference number.

DETAILED DESCRIPTION OF THE INVENTION [0116] The present invention provides improved processes and systems for assembling electronic devices, including RFID tags. The present invention provides improvements over current processes. Conventional techniques include vision-based systems that pick and place dies one at a time onto substrates. The present invention can transfer multiple dies simultaneously.

Vision-based systems are limited as far as the size of dies that may be handled, such as being limited to dies larger than 600 microns square. The present invention is applicable to dies 100 microns square and even smaller.

Furthermore, yield is poor in conventional systems, where two or more dies may be accidentally picked up at a time, causing losses of additional dies. The present invention allows for improved yield values.

[0117] The present invention provides an advantage of simplicity.

Conventional die transfer tape mechanisms may be used by the present invention. Furthermore, much higher fabrication rates are possible. Current techniques process 5-8 thousand units per hour. The present invention can provide improvements in these rates by a factor of N. For example, embodiments of the present invention can process dies 5 times as fast as conventional techniques, at 100 times as fast as conventional techniques, and at even faster rates. Furthermore, because the present invention allows for flip-chip die attachment techniques, wire bonds are not necessary.

[0118] Elements of the embodiments described herein may be combined in any manner. Example RFID tags are described in the section below.

Assembly embodiments for RFID tags are described in the next section.

Example applications for tags and tag assembly techniques are then described, followed by a description of example substrate webs and antenna layouts.

1.0 RFID Tag [0119] The present invention is directed to techniques for producing electronic devices, such as RFID tags. For illustrative purposes, the description herein primarily relates to the production of RFID tags. However, the description is also adaptable to the production of further electronic device types, as would be understood by persons skilled in the relevant art (s) from the teachings herein.

[0120] FIG. 1A shows a block diagram of an exemplary RFID tag 100, according to an embodiment of the present invention. As shown in FIG. 1A, RFID tag 100 includes a die 104 and related electronics 106 located on a tag substrate 116. Related electronics 106 includes an antenna 114 in the present example. FIGS. 1B and 1C show detailed views of exemplary RFID tags 100, indicated as RFID tags 100a and 100b. As shown in FIGS. 1B and 1C, die 104 can be mounted onto antenna 114 of related electronics 106. As is further described elsewhere herein, die 104 may be mounted in either a pads up or pads down orientation.

[0121] RFID tag 100 may be located in an area having a large number, population, or pool of RFID tags present. RFID tag 100 receives interrogation signals transmitted by one or more tag readers. According to interrogation protocols, RFID tag 100 responds to these signals. Each response includes information that identifies the corresponding RFID tag 100 of the potential pool of RFID tags present. Upon reception of a response, the tag reader determines the identity of the responding tag, thereby ascertaining the existence of the tag within a coverage area defined by the tag reader.

[0122] RFID tag 100 may be used in various applications, such as inventory control, airport baggage monitoring, as well as security and surveillance applications. Thus, RFID tag 100 can be affixed to items such as airline baggage, retail inventory, warehouse inventory, automobiles, compact discs (CDs), digital video discs (DVDs), video tapes, and other objects. RFID tag 100 enables location monitoring and real time tracking of such items.

[0123] In the present embodiment, die 104 is an integrated circuit that performs RFID operations, such as communicating with one or more tag readers (not shown) according to various interrogation protocols. Exemplary interrogation protocols are described in U. S. Patent No. 6,002, 344 issued December 14,1999 to Bandy et al. entitled System and Method for Electronic Inventory, and U. S. Patent Application No. 10/072,885, filed on February 12, 2002. Die 104 includes a plurality of contact pads that each provide an electrical connection with related electronics 106.

[0124] Related electronics 106 are connected to die 104 through a plurality of contact pads of IC die 104. In embodiments, related electronics 106 provide one or more capabilities, including RF reception and transmission capabilities, sensor functionality, power reception and storage functionality, as well as additional capabilities. The components of related electronics 106 can be printed onto a tag substrate 116 with materials, such as conductive inks.

Examples of conductive inks include silver conductors 5000,5021, and 5025, produced by DuPont Electronic Materials of Research Triangle Park, N. C.

Other materials or means suitable for printing related electronics 106 onto tag substrate 116 include polymeric dielectric composition 5018 and carbon-based PTC resistor paste 7282, which are also produced by DuPont Electronic Materials of Research Triangle Park, N. C. Other materials or means that may be used to deposit the component material onto the substrate would be apparent to persons skilled in the relevant art (s) from the teachings herein.

[0125] As shown in FIGS. 1A-1C, tag substrate 116 has a first surface that accommodates die 104, related electronics 106, as well as further components of tag 100. Tag substrate 116 also has a second surface that is opposite the first surface. An adhesive material or backing can be included on the second surface. When present, the adhesive backing enables tag 100 to be attached to objects, such as books and consumer products. Tag substrate 116 is made from a material, such as polyester, paper, plastic, fabrics such as cloth, and/or other materials such as commercially available Tyvec (Et).

[0126] In some implementations of tags 100, tag substrate 116 can include an indentation, "cavity, "or"cell" (not shown in FIGS. 1A-1C) that accommodates die 104. An example of such an implementation is included in a"pads up"orientation of die 104.

[0127] FIGS. 2A and 2B show plan and side views of an example die 104.

Die 104 includes four contact pads 204a-d that provide electrical connections between related electronics 106 and internal circuitry of die 104. Note that although four contact pads 204a-d are shown, any number of contact pads may be used, depending on a particular application. Contact pads 204 are made of an electrically conductive material during fabrication of the die. Contact pads 204 can be further built up if required by the assembly process, by the deposition of additional and/or other materials, such as gold and solder flux.

Such post processing, or"bumping, "will be known to persons skilled in the relevant art (s).

[0128] FIG. 2C shows a portion of a substrate 116 with die 104 attached thereto, according to an example embodiment of the present invention. As shown in FIG. 2C, contact pads 204a-d of die 104 are coupled to respective contact areas 210a-d of substrate 116. Contact areas 210a-d provide electrical connections to related electronics 106. The arrangement of contact pads 204a- d in a rectangular (e. g., square) shape allows for flexibility in attachment of die 104 to substrate 116, and good mechanical adherement. This arrangement allows for a range of tolerance for imperfect placement of IC die 104 on substrate 116, while still achieving acceptable electrical coupling between contact pads 204a-d and contact areas 210a-d. For example, FIG. 2D shows an imperfect placement of IC die 104 on substrate 116. However, even though IC die 104 has been improperly placed, acceptable electrical coupling is achieved between contact pads 204a-d and contact areas 210a-d.

[0129] Note that although FIGS. 2A-2D show the layout of four contact pads 204a-d collectively forming a rectangular shape, greater or lesser numbers of contact pads 204 may be used. Furthermore, contact pads 204a-d may be laid out in other shapes in embodiments of the present invention.

2.0 RFID Tag Assembly [0130] The present invention is directed to continuous-roll assembly techniques and other techniques for assembling tags, such as RFID tag 100.

Such techniques involve a continuous web (or roll) of the material of the tag antenna substrate 116 that is capable of being separated into a plurality of tags.

Alternatively, separate sheets of the material can be used as discrete substrate webs that can be separated into a plurality of tags. As described herein, the manufactured one or more tags can then be post processed for individual use.

For illustrative purposes, the techniques described herein are made with reference to assembly of RFID tag 100. However, these techniques can be applied to other tag implementations and other suitable devices, as would be apparent to persons skilled in the relevant art (s) from the teachings herein.

[0131] The present invention advantageously eliminates the restriction of assembling electronic devices, such as RFID tags, one at a time, allowing multiple electronic devices to be assembled in parallel. The present invention provides a continuous-roll technique that is scalable and provides much higher throughput assembly rates than conventional pick and place techniques.

[0132] FIG. 3 shows a flowchart 300 with example steps relating to continuous-roll production of RFID tags 100, according to example embodiments of the present invention. FIG. 3 shows a flowchart illustrating a process 300 for assembling tags 100. Process 300 begins with a step 302. In step 300, a wafer 400 having a plurality of dies 104 is produced. FIG. 4A illustrates a plan view of an exemplary wafer 400. As illustrated in FIG. 4A, a plurality of dies 104 are arranged in a plurality of rows 402a-n.

[0133] In a step 304, wafer 400 is optionally applied to a support structure or surface 404. Support surface 404 includes an adhesive material to provide adhesiveness. For example support surface 404 may be an adhesive tape that holds wafer 400 in place for subsequent processing. FIG. 4B shows an example view of wafer 400 in contact with an example support surface 404.

In some embodiments, wafer 400 does not need to be attached to a support surface, and can be operated on directly.

[0134] In a step 306, the plurality of dies 104 on wafer 400 are separated. For example, step 306 may include scribing wafer 400 according to a process, such as laser etching. FIG. 5 shows a view of wafer 400 having example separated dies 104 that are in contact with support surface 404. FIG. 5 shows a plurality of scribe lines 502a-1 that indicate locations where dies 104 are separated.

[0135] In a step 308, the plurality of dies 104 is transferred to a substrate. For example, dies 104 can be transferred from support surface 404 to tag substrates 116. Alternatively, dies 104 can be directly transferred from wafer 400 to substrates 116. In an embodiment, step 308 may allow for"pads down" transfer. Alternatively, step 308 may allow for"pads up"transfer. As used herein the terms"pads up"and"pads down"denote alternative implementations of tags 100. In particular, these terms designate the orientation of connection pads 204 in relation to tag substrate 116. In a"pads up"orientation for tag 100, die 104 is transferred to tag substrate 116 with pads 204a-204d facing away from tag substrate 116. In a"pads down" orientation for tag 100, die 104 is transferred to tag substrate 116 with pads 204a-204d facing towards, and in contact with tag substrate 116. An example of step 308 involving"pads up"transfer is described in greater detail herein with reference to FIG. 11. An example of step 308 involving"pads down" transfer is described in greater detail herein with reference to FIG. 16.

Note that step 308 may include multiple die transfer iterations. For example, in step 308, dies 104 may be directly transferred from a wafer 400 to substrates 116. Alternatively, dies 104 may be transferred to an intermediate structure, and subsequently transferred to substrates 116. Example embodiments of such die transfer options are described below.

Note that steps 306 and 308 can be performed simultaneously in some embodiments. This is indicated in FIG. 3 by step 320, which includes both of steps 306 and 308. Example embodiments where dies 104 of a wafer 400 are separated, and simultaneously transferred to a subsequent surface, are described below.

In a step 310, post processing is performed. During step 310, assembly of RFID tag (s) 100 is completed. Example embodiments for step 310 are described in further detail below with reference to FIGS. 8 and 9, for example.

2.0. 1 Example Wafer Expanding and Die Transfer Embodiments '] In an embodiment, flowchart 300, shown in FIG. 3, can include an additional step after step 306, where the wafer is expanded. For example, in FIG. 6, a wafer that has been separated on a support surface or structure 602 is shown being expanded in all directions. In embodiments, support surface 602 attaching the separated dies 104 can be stretched in any number of one or more axes in the plane of the wafer. For example, support surface 602 can be expanded in both orthogonal X and Y axes. Support surface 602 can be expanded by the same amount, or different amounts, in the X and Y axes. By expanding the wafer, an area of the support surface 602 is increased. By increasing an area of the support surface 602, a space or gap 604 between adjacent dies 104 can be increased. By increasing space or gap 604 between adjacent dies 104, dies 104 may be more easily transferred from the support surface 602 to another surface, as is described further below.

[0140] FIGs. 7A-7C show example steps related to a flowchart 700 for expanding a wafer, and transferring dies therewith, according to embodiments of the present invention. The steps shown in FIGs. 7A-7C are described in detail below. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion.

[0141] Flowchart 700 shown in FIG. 7A begins with step 702. In step 702, a wafer is attached to a support structure. This step is similar to step 304 shown in FIG. 3.

[0142] In step 704, the wafer is separated on the support structure into a plurality of dies. For example, step 704 is similar to step 306 shown in FIG. 3.

[0143] In step 706, an area of the support structure is increased to increase a space between adjacent dies of the plurality of dies. For example, the area of the support structure can be increased along one or more axes to increase an area of the support structure. For example, the support structure may be stretched along orthogonal X and Y axes.

[0144] FIG. 7B shows an additional step for flowchart 700, according to an example embodiment of the present invention. In step 708, the plurality of dies are transferred from the support structure. For example, in embodiments, the plurality of dies can be transferred to an intermediate surface, or can even be transferred to a final destination surface, such as a surface of a substrate.

Because an area of the support surface has been enlarged, die transfer to an intermediate or final surface can be more easily accomplished, as there is a greater spacing between dies (i. e.,"die pitch"), which can make the transfer of the dies more easily accomplished. For example, if the plurality of dies are being transferred to substrates, the substrates can be larger or further spread apart because the gap or space between dies has been increased on the support structure. This allows for more space for the structures performing the die transfer, for example.

[0145] FIG. 7C shows additional steps for flowchart 700 of FIG. 7A, according to another embodiment of the present invention. The steps of FIG. 7C create a solid grid, or die frame, between the dies on the enlarged support structure to hold the dies so that the dies may be later transferred to another surface. Thus, the steps of FIG. 7C may be used to create a solid grid/die frame that removably holds dies. Such a die frame is further described in related U. S. Serial No. 10/322,701, entitled"Die Frame Apparatus and Method of Transferring Dies Therewith." [0146] The steps shown in FIG. 7C begin with the step 710. In step 710, a solidifiable material is inserted into the increased space between adjacent dies.

[0147] In step 712, the solidifiable material is caused to harden into a solid grid that removably holds the plurality of dies.

[0148] In step 714, the support structure is removed from the solid grid that removably holds the plurality of dies. Thus, the dies remain removably held by the solid grid.

[0149] In step 716, at least one die of the plurality of dies is transferred from the solid grid to a surface. Thus, the solid grid can be used to transfer the dies that are removably held.

[0150] As described above with respect to FIGS. 6 and 7A-7C, a singulated wafer attached to a support structure may be expanded, to increase a space between the separated dies of the wafer. This increase of space between the separated dies may be advantageously used to enhance ease of the transfer of the dies from the support structure to a target destination surface, such as an intermediate die transfer surface, or to one or more destination substrates.

Example embodiments for expanding a wafer, and for transferring dies therefrom, are described below. These example embodiments are provided for illustrative purposes, and are not limiting. Additional embodiments for expanding wafers and transferring dies will be apparent to persons skilled in the relevant art (s) from the teachings herein. These additional embodiments are within the scope and spirit of the present invention.

0151] FIG. 162A shows a plan view of a singulated wafer attached to support structure 602, which is held in a wafer frame 606. As shown in FIG. 162A, a space or gap 604 is present between dies 104 on support structure 602. FIG.

162B shows a cross-sectional view of the singulated wafer attached to support structure 602 shown in FIG. 162A. As shown in the examples of FIGS. 162A and 162B, wafer frame 606 surrounds dies 104, and has a first portion 16202a attached to a first surface 16204 of support structure 602 and a second portion 16202b attached to an opposed second surface 16206 of support structure 602.

As shown in FIG. 162B, first portion 16202a may be coupled to second portion 16202b by one or more structural links 16204. Structural links 16204 may be pins, bolts, screws, or any other suitable coupling device. Wafer frame 606 holds support structure 602 relatively taut'so that dies 104 may be accessed from support structure 602.

[0152] An area of support structure 602 may be increased in various ways to increase space 604 between dies 104, according to step 706 described above with respect to FIG. 7A. For example, in an embodiment, wafer frame 606 may comprises a plurality of separate segments. The separate segments may be pulled apart from each other to increase an area of support structure 604.

[0153] FIG. 163A shows wafer frame 606 that includes eight wafer frame segments 16302a-h, according to an example embodiment of the present invention. In FIG. 163A, dies 104 are separated on support structure 604, prior to being expanded. Each of wafer frame segments 16302a-h includes one or more corresponding connection points 16304, to which a wafer expander mechanism may connect. For example, connection points 16304 may be holes, knobs, or any other connection mechanism type.

[0154] FIG. 163B shows support structure 604 being expanded, by radially pulling apart wafer frame segments 16302a-h. In FIG. 163B, an expanded gap or space 16310 exists between dies 104 on support structure 604. Space 16310 in FIG. 163B is greater than space 604 shown in FIG. 163A due to the pulling apart of wafer frame segments 16302a-h.

[0155] In another example embodiment, an area of support structure 602 may be increased to increase a space between dies by first stretching support structure 602, and subsequently attaching wafer frame 606 to the enlarged support structure 602 to hold it in an expanded state.

[0156] For example, FIG. 164A shows dies 104 of a singulated wafer attached to a support structure 16402, in an unexpanded state. As shown in FIG. 164A, dies 104 are separated by space 604. FIG. 164B shows support structure 16402 being radially stretched/expanded, to increase an area of support structure 16402. In FIG. 164B, an expanded gap or space 16410 exists between dies 104 on support structure 16402. Space 16410 in FIG. 164B is greater than space 604 shown in FIG. 164A due to the stretching or expanding of support structure 16402. Support structure 16410 can be stretched in any conventional or otherwise known manner. FIG. 164C shows wafer frame 606 attached to the expanded support structure 16410 of FIG. 164B, to maintain support structure 16410 in the expanded state.

[0157] After a support structure has been expanded, to increase a space between dies, such as described above with regards to the examples of FIGS.

163A, 163B, and 164A-164C, the expanded support structure/wafer may be further processed, to enhance/enable transfer of dies from the support structure to another surface. For example, FIG. 165 shows a cross-sectional view of an expanded support structure 16502 that attaches dies 104 of a singulated wafer, having expanded gaps or spaces 16504 between dies 104 (wafer frame 606 not shown). Examples for further processing of expanded support structure 16502 attaching dies 104 are described below.

[0158] For example, as shown in FIG. 166, in an embodiment, a die frame 16602 may be formed around dies in the expanded spaces 16504. For example, die frame 16602 may be formed according to the flowchart shown in FIG. 7C, or by other mechanisms or processes. Die frame 16602 holding dies 104 may then be peeled/separated from support structure 16502. Dies 104 may be transferred from die frame 16602 to subsequent surfaces as needed.

[0159] In another example embodiment, as shown in FIG. 167, a support layer 16702 can be formed on expanded support structure 16502 on a surface opposite of dies 104. Support layer 16702 can be applied as a liquid that solidifies (e. g., an epoxy), as a solid layer that attaches to support structure 16502, as an adhesive structure, or as any other support layer type. Support layer 16702 adheres to support structure 16502, and maintains support structure 16502 in an expanded state. Thus, in an embodiment, wafer frame 606 can be removed from support structure 16502, while support layer 16702 maintains support structure 16502 in an expanded state.

[0160] In another example embodiment, as shown in FIG. 168, a support layer 16802, generally similar to support layer 16702 of FIG. 167, can be formed on expanded dies 104. Support layer 16802 can be applied as a liquid that solidifies (e. g. , an epoxy), as a solid layer that attaches to support structure 16502, as an adhesive structure, or as any other support layer type. In an embodiment, such as shown in FIG. 168, support layer 16802 (such as when applied as a liquid) does not enter spaces 16504 between dies 104. In this manner, support structure 16502 can subsequently be removed/peeled from dies 104 if desired, leaving support layer 16802 supporting dies 104 in the expanded state. In an alternative embodiment, support layer 16802 (such as when applied as a liquid) does enter spaces 16504.

[0161] In another example embodiment, the expanded support structure 16502 is applied to a die plate 16902, and dies 104 are transferred from expanded support structure 16502 to one or more subsequent surfaces using die plate 16902. For example, as shown in FIG. 169, a pin plate 16904 having one or more pins 16906 can be applied to die plate 16902. Pins 16906 pass through corresponding holes 16910 of die plate 16902 to push/punch dies from expanded support structure 16502 onto a subsequent surface (not shown in FIG. 169), such as an intermediate transfer surface, or one or more substrates.

Because dies 104 are more greatly spread out on support surface 16502 (e. g., have greater die pitch) due to the expanding of support surface 16502, dies 104 can be more easily transferred in parallel to a corresponding plurality of substrates, of various sizes, depending on the spread of dies 104 on support surface 16502.

[0162] Example pin plate embodiments, and further example die transfer embodiments, are described elsewhere herein.

[0163] FIG. 170 shows an example system 17000 for expanding a wafer, and utilizing an expanded wafer, according to an embodiment of the present invention. Further system embodiments will be apparent to persons skilled in the relevant art (s) from the teachings herein.

[0164] As shown in FIG. 170, system 17000 includes a wafer frame 17002, a wafer expander 17004, an alignment system 17006, a die transfer mechanism 17008, a substrate server 17010, and an expanded wafer processor 17014.

Wafer frame 17002 holds a support structure 17012 that attaches a plurality of dies 104 of a separated wafer.

[0165] Wafer expander 17004 increases an area of support structure 17012 to increase a spacing of dies 104 on support structure 17012. Thus, for example, wafer expander 17004 can perform step 706 shown in FIG. 7A. For example, in an embodiment, elements of wafer expander 17004 couple to wafer frame 17002 by connection points or other mechanisms. Wafer expander 17004 may expand support structure 17012 using mechanical (e. g. , motors), electromechanical, pneumatic, magnetic, or any other mechanism. In an embodiment for a wafer frame having multiple segments, such as shown in FIGS. 163A and 163B, wafer expander 17004 may include and/or control multiple separate motors, etc. , for moving apart the multiple segments to spread the support structure.

[0166] Alignment system 17006 monitors and detects the amount of spreading of support structure 17012, and/or the spreading of dies 104, to ensure that dies 104 are spread to a desired spacing/die pitch. In an embodiment, alignment system 17006 is coupled to wafer expander 17004 to feed back spacing measurements to wafer expander 17004. In this manner, dies 104 can be spread to a desired spacing/die pitch to be handled by a pin plate or other die transfer mechanism, to be transferred to a subsequent surface. For example, alignment system 17006 may be an optical alignment system, a mechanical alignment system, and/or any other type of alignment system.

[0167] As shown in FIG. 170, once support structure 17012 has been appropriately expanded, the combination of expanded support structure 17012, dies 104, and die frame 17002 (i. e. , the expanded wafer) may be further processed by expanded wafer processor 17014 (when present). Expanded wafer processor 17014 may be used to create a die frame (e. g. , as described above with respect to FIGS. 7C and 166), to add one or more layers (e. g. , such as support layers 16702 and 16802 described above), to remove support structure 17012 if desired, to attach support structure 17012 to a die plate (e. g., such as die plate 16902), and/or for other processing of an expanded wafer.

[0168] After processing by wafer processor 17014, a processed expanded wafer 17016 can be further processed, such as by transferring dies from processes expanded wafer 17016 to intermediate surfaces or destination surfaces, such as one or more substrates. For example, as shown in FIG. 170, a substrate (or other target surface) server 17010 may be present to supply substrates. The substrates may be supplied singly, or in webs of multiple substrates. Die transfer mechanism 17008 is used to transfer dies 104 from processed expanded wafer 17016 to substrates of substrate server 17010, according to any die transfer process or mechanism. For example, die transfer mechanism 17008 may include a pin plate (e. g. , such as pin plate 16904 shown in FIG. 169) to push/punch dies from processed expanded wafer 17016.

For instance, die transfer mechanism 17008 may be used to perform step 708 described above with respect to FIG. 7B.

2.0. 2 Tag Authentication Embodiments [00100] During the device assembly process, the operation of assembled devices may be authenticated. In other words, as devices are manufactured, they may be checked to determine whether they are operating properly. For example, FIG. 8 shows a simplified device assembly system 800 with device authentication, according to an example embodiment of the present invention.

System 800 illustrates an example process for creating devices, authenticating devices, and providing an indication of defectively manufactured devices.

System 800 includes a die transfer module 802, a device authentication module 804, an optional inker 806, and a substrate conveyor system 812.

[00101] System 800 receives wafers 400 or other surfaces or containers having a plurality of dies. Each die has a unique wafer identification number that is programmed in memory on each die. The wafer identification numbers are unique within a wafer. The wafer identification number is used to track the die during the assembly process and/or during post processing. In addition, the wafer identification number is used during die/device authentication.

[00102] In an embodiment, the wafer identification number is a die identification number (e. g. , tag ID) that is unique among dies in a lot of dies located on multiple wafers. Alternatively, the wafer identification number may be a smaller number that is unique only to dies within a single wafer. In an embodiment, the wafer identification number is stored in memory (e. g., ROM) on the die. In applications where the die identification number is not programmed on the die during wafer manufacture, a smaller number, the wafer identification number, is stored in ROM on the die. Thus, the number of bits required to uniquely identify a die on wafer is related to the number of dies on the wafer and/or the application. FIG. 152 shows an example wafer 15200 having 48 dies, with wafer identification numbers 1-48.

[00103] For each wafer entering system 800, each die is identifiable and the location of each die is know. For example, a wafer map indicating the location of each die on the wafer may be maintained, stored, or other recorded.

In the wafer map, each wafer identification number is correlated with its location on the die (also referred to as"geolocation"). System 800 stores the wafer map for each wafer being processed. In an alternate embodiment, system 800 accesses an external system for the wafer map when required during processing.

[00104] Substrate conveyor system 812 conveys a continuous web 808 of substrates 116, to which dies 104 can be attached in large quantities. Web 808 can be a continuous roll of substrates 116, or can be discrete, separate sheets of substrates 116. Substrate conveyor system 812 typically moves the web of substrates in increments related to the substrate size.

[00105] Die transfer module 802 transfers dies 104 from received wafers 400 onto the substrates 116 of web 808. Die transfer module 802 can include any of the structures and processes described herein or in the referenced applications for transferring dies from wafers to substrates. For example, the die transfer module can include any of the structures and operations for transferring dies from wafers directly to substrates, for transferring dies from wafers to intermediate surfaces, and for transferring dies from intermediate surfaces to substrates. For example, die transfer module 802 may perform the steps 304,306, and/or 308, shown in FIG. 3. As shown in FIG. 8, die transfer module 802 receives one or more wafers 400, and transfers dies 104 to substrates 116 of web 808.

[00106] System 800 tracks the location of each die transferred from the wafer onto a substrate. As described above, using the wafer map, system 800 can determine the location of each die within a wafer. System 800 tracks the location of the wafer in the system. Furthermore, system 800 tracks which dies are transferred to which substrates in web 808. Therefore, for each transfer step, system 800 knows the dies being transferred and the location of the substrates receiving each die.

[00107] In addition, system 800 tracks the location of substrates of substrate web 808. For example, the location of the substrates in the system can be determined because the system moves the substrate web incrementally. For example, the location of a substrate can be tracked by an increment count (e. g. , number of increments the substrate web is moved forward after transfer of the die to the substrate) or by an elapsed time since transfer.

[00108] For example, FIG. 153 shows the location of a plurality of dies from wafer 15200. The location of wafer 15200 relative to substrate web 808 prior to die transfer is shown as location 15340. In the example of FIG. 153, nine dies are transferred simultaneously in a 3 x 3 array. As shown in location 15340, die 10 is positioned adjacent to substrate 116a; die 23 is positioned adjacent to substrate 116d, etc. In addition, as shown at location 840, when dies are transferred, substrate 116a is at location A; substrate 116d is at location B ; and substrate 116g is at location C. As further is shown in 15340, dies 1-4,5, 7,9, 11-16,17, 18,20, 22,24, 25-32,33, 35,37, and 39-48 are not transferred in this iteration. After die transfer, substrate web 808 is moved in a predetermined increment or increments (e. g. , to expose the next 3 x 3 array of substrates to dies remaining in wafer 15200). The location of the substrate web after the substrate web is incremented is shown as location 15380. As shown in location 15380, die 10 is located on substrate 116a which is at location X; die 23 is located on substrate 116d which is at location Y, die 38 is located on substrate 116g which is at location Z, etc.

[00109] System 800 may track the location of dies/devices in system 800 during the assembly process. In addition or alternatively system 800 may calculate the location of one or more devices in system 800 at a specific time using known information. In an embodiment, die/device location information is stored (or tracked) locally in system 800. In addition or alternatively location information is stored (or tracked) in an external system.

[00110] For example, a die/device identifier (e. g. , wafer identification number) is stored and correlated with the time or increment when the die was transferred to a substrate. In addition, or alternatively, a specific substrate or substrate location may be stored and correlated with the die/device identifier.

The system then tracks the time/increments as the substrate web is moved through the system. The location of a die/device at a specific point during the process can be calculated using the difference between the current increment/time and the increment/time of transfer. This difference can be used to identify the location of the substrate containing the die/device in the system.

[00111] In an embodiment, location information is continually or periodically updated for each die/device as the die/device moves through system 800. For example, each time the substrate web is incremented, the location information for the die/device in the system is updated.

[00112] Note that information regarding the location of a device in the system may be tracked or calculated for each device during the assembly process.

Alternatively, device location may be calculated only for defective devices.

[00113] Furthermore, as shown in FIG. 8, after dies are applied to substrates to create devices, operation of the devices is verified by the device authentication module 804. For example, when the devices are RFID tags, the device authentication module 804 includes an antenna. During authentication, the antenna 804 performs a read of the tags that have been assembled to verify whether the tags are operating properly. For example, antenna 804 transmits a signal that is received by tags that have been assembled. For example, die 104e on substrate 116e forms an assembled tag. If operating properly, the assembled tag responds to the signal. Using any appropriate communication protocol, antenna 804 transmits the tag's identification number stored within the tag, and if the tag is operating properly, the tag will respond. If the tag is not operating properly, the tag will not respond.

[00114] In a preferred embodiment, during tag assembly, an antenna in the device authentication module 804 performs a"far field"read of assembled tags. Alternatively, a"near field"read can be performed. A space or region immediately surrounding an antenna, in which reactive components predominate, is known as the reactive near field region. The size of this region varies for different antennas. For most antennas, however, the outer limit of a near field read is on the order of a few wavelengths or less. Beyond the reactive near field region, the"radiating field"predominates. The radiating region is divided into two sub-regions, the"radiating near field" region and the"far field"region. In the radiating near field region, the relative angular distribution of the field (the usual radiation pattern) is dependent on the distance from the antenna. In a far field region, the relative angular distribution of the field becomes independent of the distance. According to the present invention, a read using the far field region is utilized, as a far field read.

[00115] An advantage of using the far field region, according to the present invention, is that one or a small number of antennas can be used to verify operation of a large number of assembled tags. This contrasts with using a near field region, in which a radiating element must be applied to each tag under test in close proximity. Thus, in a near field read, a large number of radiating elements is required, while in a far field read, a small number of radiating elements is required. Note, however, in alternative embodiments, the near field regions may be used to verify operation of assembled tags.

[00116] System 800 identifies the location in the system of each device not operating properly. As a result of the device authentication process, device authentication module 804 knows the wafer identification number of each device not operating properly. In an embodiment, system 800 uses the wafer identification number to access location information to identify the location of defective devices.

[00117] In an embodiment, location information for each die/device is tracked by the system during the assembly process. Thus, no additional calculation is required. Alternatively, the location of the defective device is calculated using known data, as described above.

[00118] In an embodiment, the identification of the location of a defective device in the system is performed by the device authentication module. In an alternative embodiment, the identification of the location of a defective device in the system is performed by the inker or similar indication apparatus.

[00119] Devices that the device authentication module 804 determines are not operating correctly must be indicated. For example, tags that do not respond to the read performed by an antenna in the device authentication module 804 are indicated. Such devices are indicated because they are defective (e. g. , do not meet defined operating parameters), and must be rejected. A variety of methods may be used to keep track of such defective tags. For example, in an embodiment, as shown in FIG. 8, an inker 806 may be used to mark defective devices. For example, as shown in FIG. 8, inker 806 has marked a device that includes die 104h and substrate 116h, with a mark 814. Mark 814 may be an ink material, or other marking material, to make a defective device apparent on web 808. Mark 814 makes a defective device readily identifiable, and the device can be disposed of.

[00120] In an alternative embodiment, an inker 806 is not present. Instead, the identification and/or locations of defective devices on web 808 and/or in system 800 are stored by a computer system. The defective tag can then later be located and disposed of, using the stored location of the device. This is possible, as the wafer identification numbers stored in dies 104 are known prior to being attached to substrates 116. Furthermore, the location in web 808 of each substrate 116 to which a die 104 is attached is known. Thus, the defective tags can be located in web 808.

[00121] FIG. 9 shows a flowchart 900 including example steps for authenticating one or more assembled devices during the assembly process, as described above, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on flowchart 900. Note that ways of tracking or indicating defective devices, other than described above, are applicable to the present invention.

[00122] Flowchart 900 begins at step 910 when a web of substrates and a wafer having dies is received. In an embodiment, a wafer map associated with the wafer is also received. Alternatively, a wafer map is generated by system 800 or accessed from an external system when required during assembly process.

[00123] In step 920, dies from the wafer are transferred to substrates on the web to form a plurality of devices.

[00124] In step 930, the web is moved incrementally.

[00125] In step 940, the operation of a device is authenticated. For example, if the device is an RFID tag, a far field read of the RFID tag is performed.

[00126] In step 950, a determination is made whether the die/device was found to be defective (e. g. , device not operating properly) during step 940. If the device is defective, operation proceeds to step 960. Otherwise, operation proceeds to step 975. For example, when the device is an RFID tag, a device that does not respond to the far field read is considered defective.

[00127] In step 960, the location of the device is identified. For example, the wafer identification number of the defective device is known. In an example embodiment, the location of each die/device during the assembly process may be tracked and/or calculated and stored internally or externally to system 800.

In this exemplary embodiment, in step 960, the wafer identification number is used to access the location information for that die/device on the substrate. In an additional exemplary embodiment, in step 960, the location of the defective die is calculated in real-time using available data.

[00128] In step 970, the device that is not working properly is indicated. For example, the defective device is marked with ink.

[00129] In step 975, a determination is made whether any devices remain to be authenticated. If a device remains to be authenticated, operation proceed to step 940. Steps 940-975 are repeated for each device to be authenticated.

Otherwise, operation proceeds to step 980.

[0169] In step 980, the assembly process is continued. For example, if dies on the wafer remain to be transferred, operation may proceed to step 920. If no dies remain on the wafer, operation may proceed to step 910.

[0170] Note that several steps in flowchart 900 may occur in parallel. For example, a plurality of devices could be authenticated (e. g., steps 940-975) at substantially the same time as a plurality of dies is being transferred to substrates (e. g. , step 920).

2.1 Die Transfer Embodiments [0171] Step 308 shown in FIG. 3, and discussed above, relates to transferring dies to a tag substrate. The dies can be attached to a support surface (e. g. , as shown in FIG. 5), or can be transferred directly from the wafer, and can be transferred to the tag substrate by a variety of techniques. Conventionally, the transfer is accomplished using a pick and place tool. The pick and place tool uses a vacuum die collet controlled by a robotic mechanism that picks up the die from the support structure by a suction action, and holds the die securely in the die collet. The pick and place tool deposits the die into a die carrier or transfer surface. For example, a suitable transfer surface is a"punch tape" manufactured by Mulbauer, Germany. A disadvantage of the present pick and place approach is that only one die at a time may be transferred. Hence, the present pick and place approach does not scale well for very high throughput rates.

[0172] The present invention allows for the transfer of more than one die at a time from a support surface to a transfer surface. In fact, the present invention allows for the transfer of more than one die between any two surfaces, including transferring dies from a wafer or support surface to an intermediate surface, transferring dies between multiple intermediate surfaces, transferring dies between an intermediate surface and the final substrate surface, and transferring dies directly from a wafer or support surface to the final substrate surface.

[0173] FIG. 10 shows a high-level system diagram 1000 that provides a representation of the different modes or paths of transfer of dies from wafers to substrates. FIG. 10 shows a wafer 400, a web 808, and a transfer surface 1010. Two paths are shown in FIG. 10 for transferring dies, a first path 1002, which is a direct path, and a second path 1004, which is a path having intermediate steps. For example, as shown in FIG. 10, first path 1002 leads directly from wafer 400 to web 808. In other words, dies can be transferred from wafer 400 to substrates of substrate 808 directly, without the dies having first to be transferred from wafer 400 to another surface or storage structure.

However, according to path 1004, at least two steps are required, path 1004A and path 1004B. For path 1004A, dies are first transferred from wafer 400 to an intermediate transfer surface 1010. The dies then are transferred from transfer surface 1010 via path 1004B to the substrates of web 808. Paths 1002 and 1004 each have their advantages. For example, path 1002 can have fewer steps, but can have issues of die registration, and other difficulties. Path 1004 typically has a larger number of steps than path 1002, but transfer of dies from wafer 400 to a transfer surface 1010 can make die transfer to the substrates of web 808 easier, as die registration may be easier.

[0174] FIGS. 11 and 12 show flowcharts providing steps for transferring dies from a first surface to a second surface, according to embodiments of the present invention. Structural embodiments of the present invention will be apparent to persons skilled in the relevant art (s) based on the following discussion. These steps are described in detail below.

[0175] Flowchart 1100 begins with step 1102. In step 1102, a plurality of dies attached to a support surface is received. For example, the dies are dies 104, which are shown attached to a support surface 404 in FIG. 4A. For example, the support surface can be a"green tape"or"blue tape"as would be known to persons skilled in the relevant art (s).

[0176] In step 1104, the plurality of dies are transferred to a subsequent surface. For example, dies 104 may be transferred according to embodiments of the present invention. For example, the dies may be transferred by an adhesive tape, a punch tape, a multi-barrel transport mechanism and/or process, die frame, pin plate, such as are further described below, and may be transferred by other mechanisms and processes, or by combinations of the mechanisms/processes described herein. In embodiments, the subsequent surface can be an intermediate surface or an actual final substrate. For example, the intermediate surface can be a transfer surface, including a"blue tape, "as would be known to persons skilled in the relevant art (s). When the subsequent surface is a substrate, the subsequent surface may be a substrate structure that includes a plurality of tag substrates, or may be another substrate type.

[0177] In block 1106, if the subsequent surface is a substrate to which the dies are going to be permanently attached, the process of flowchart 1100 is complete. The process can then proceed to step 310 of flowchart 300, if desired. If the subsequent surface is not a final surface, then the process proceeds to step 1104, where the plurality of dies are then transferred to another subsequent surface. Step 1104 may be repeated as many times as is required by the particular application.

[0178] Flowchart 1200 of FIG. 12 is substantially similar to flowchart of 1100. However, instead of including step 1102, flowchart 1200 includes step 1202. In step 1202, a wafer that includes a plurality of dies is received. Thus, in flowchart 1200, a wafer 400 is operated on directly, without being applied to a support surface or structure. Embodiments for both of flowcharts 1100 and 1200 are described herein.

[0179] Any of the intermediate/transfer surfaces and final substrate surfaces may or may not have cells formed therein for dies to reside therein. Various processes described below may be used to transfer multiple dies simultaneously between first and second surfaces, according to embodiments of the present invention. In any of the processes described herein, dies may be transferred in either pads-up or pads-down orientations from one surface to another.

[0180] The die transfer processes described herein include transfer using an adhesive surface, a parallel die punch process, die plates, including die receptacle structures, pin plates, die transfer heads, and die transfer head coverage patterns. Elements of the die transfer processes described herein may be combined in any way, as would be understood by persons skilled in the relevant art (s). These die transfer processes, and related example structures for performing these processes, are further described in the following subsections.

2.1. 1 Die Transfer into a Die Receptacle Structure [0181] According to an embodiment of the present invention, dies can be transferred from a wafer or support structure into cells of a die receptacle structure. The die receptacle structure has a plurality of cells, typically arranged in an array of rows and columns of cells, where each cell can hold a die. After dies are transferred into the die receptacle structure, the dies can then be transferred to subsequent intermediate/transfer structures or surfaces, or to a final structure or surface, such as a substrate.

[0182] For example, FIGs. 13A and 13B show plan and a cross-sectional views of an example die receptacle structure 1300, according to an embodiment of the present invention. As shown in FIGs. 13A and 13B, die receptacle structure 1300 comprises a body 1302. A plurality of cells 1304 are formed in a surface of body 1302. Cells 1304 can each hold or contain a die such as a die 104. As shown in FIG. 13A, cells 1304 are substantially square or rectangular, but cells 1304 can have alternative shapes.

[0183] Furthermore, as shown in FIGs. 13A and 13B, each cell 1304 has a corresponding opening or hole 1306. While cells 1304 are formed in a first surface of body 1302, holes 1306 extend all the way through body 1302, being open in a corresponding cell 1304 at the first surface and at a second surface of body 1302.

[0184] As shown in FIG. 13A, body 1302 is substantially square or rectangular in shape, although body 1302 can have other shapes. Furthermore, as shown in FIG. 13B, body 1302 can be flat, having a substantially planar shape. Note, however, that body 1302 can have any applicable thickness. In embodiments, body 1302 can be made from numerous materials, including a metal or combination of metals/alloy, a plastic, a polymer, glass, a substrate material, other material, and/or any combination thereof. Furthermore, note that although holes 1306 are shown in FIG. 13A as being substantially square or rectangular in shape, holes 1306 can have other shapes, including round or elliptical. Furthermore, note that a size or area of a cell 1304 is greater than a size or diameter of a hole 1306. Note, however, that the relative sizes of cell 1304 and hole 1306 can vary from that shown in FIGs. 13A and 13B, where hole 1306 has a size much closer to the size of cell 1304. Furthermore, a size of hole 1306 can be much smaller relative to a size of cell 1304.

[0185] Die receptacle structure 1300 is referred to by other names, including a waffle structure, a waffle grid, and a nest structure or nest plate. Furthermore, die receptacle structure is considered a type of"die plate"that has cells formed therein. Further die plate types are described elsewhere herein, including those which do not have cells formed therein.

[0186] Note that a die receptacle structure 1300 can be formed to hold any number of dies. For example, a die receptacle structure 1300 can be formed to hold a number of dies in the 10s, 100s, 1, 000s, 10,000s, and greater numbers of dies.

[0187] Furthermore, note that cells 1304 can be referred to by other names.

For example, cells 1304 can be referred to as cavities, cubbies, and by other similar names.

[0188] FIG. 14 shows a perspective view of a die receptacle structure 1300, according to an example embodiment of the present invention.

[0189] FIG. 15 shows a plurality of dies 104 attached to a support structure 404 (the support structure 404 is shown to be transparent, for illustrative purposes) that is aligned over a die receptacle structure 1300, for die transfer purposes. Each die 104 attached to support structure 404 is aligned over a corresponding cell 1304 of die receptacle structure 1300.

[0190] FIG. 16 shows a die receptacle structure 1300 that has all cells 1304 filled with a corresponding die 104, according to an example embodiment of the present invention.

[0191] FIGs. 17A-17D show various views of a portion of a die receptacle structure 1300, according to example embodiments of the present invention.

FIG. 17A shows an first side cross-sectional view of a die receptacle structure 1300 that is filled with dies 104, showing example dimension values for various dimensions of the example die receptacle structure 1300. FIG. 17B shows a second side cross-sectional view (i. e. die receptacle structure 1300 is rotated by 90 degrees) of the die receptacle structure 1300, that is filled with dies 104, also showing example dimensional values. FIG. 17C shows a perspective view of the die receptacle structure 1300. FIG. 17D shows a die 104 as it would reside in a cell 1304 (not shown), with a punch-pin that can be used to move the die 104 out of cell 1304, according to embodiments of the present invention.

[0192] FIGs. 18A and 18B show perspective and bottom views, respectively, of a single cell 1304, according to embodiments of the present invention.

FIG. 18A shows example dimensional values for various dimensions of the example cell 1304. The bottom view of FIG. 18B shows dimensions of the bottom of the cell 1304, including example dimensions for hole 1306 that corresponds to cell 1304.

[0193] Thus, in embodiments, die receptacle structure 1300 is an example of transfer structure 1010 shown in FIG. 10. Die receptacle structure 1300 can be used to transfer dies from a wafer to a substrate, or to another intermediate transfer structure.

[0194] FIG. 19 shows an example die transfer system 1900 that can be used to transfer dies from a wafer 400 to a die receptacle structure 1300, according to an example embodiment of the present invention. For example, system 1900 can be used to transfer dies along path 1004A, shown in FIG. 10. System 1900 includes a wafer 400, die receptacle structure 1300, and a vacuum source 1902. In the example of FIG. 19, wafer 400 is held in position by a jig or chuck 1904, and die receptacle structure 1300 is held in position by a jig or chuck 1906. A vacuum source chuck 1908 interfaces vacuum source 1902 with a second surface of die receptacle structure 1300. Wafer 400 is aligned with the first surface of die receptacle structure 1300.

[0195] During operation of the present invention, dies 104 of wafer 400 pass from wafer 400 to die receptacle structure 1300 due to a suction of vacuum source 1902. For example, as shown in FIG. 19, vacuum source 1902 creates a suction that is directed as shown by arrows 1910, that moves dies that are separated from wafer 400 into cells 1304 of die receptacle structure 1300.

System 1900 may be varied in many ways to transfer dies from wafer 400, or from a support structure, into die receptacle structure, according to embodiments of the present invention. These embodiments are described in further detail in the following paragraphs.

[0196] FIG. 20 shows example steps related to a flowchart 2000 for transferring dies from a wafer into a die receptacle structure, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion. Note that in alternative embodiments, the steps shown in FIG. 20 can occur in an order other than that shown.

[0197] FIGs. 21-27 relate to the steps of flowchart 2000. For example, FIG. 21 shows an example die receptacle structure 1300, according to an embodiment of the present invention. As shown in FIG. 21, an adhesive material has been applied to the first surface of die receptacle structure 1300.

Thus, each of cells 1304 in die receptacle structure have an adhesive material layer 2102 formed therein. Adhesive material layer 2102 may be any type of adhesive material, including an epoxy, an adhesive tape, or any other adhesive material.

0198] FIG. 22 relates to step 2002 of flowchart 2000 shown in FIG. 20. As shown in FIG. 22, wafer 400 is being positioned relative to die receptacle structure 1300 so that each die 104 of wafer 400 is positioned adjacent to a corresponding cell 1304 of the plurality of cells 1304 in the first surface of die receptacle structure 1300.

[0199] FIG. 23 shows wafer 400 positioned even more closely adjacent to die receptacle structure 1300. Furthermore, a vacuum or suction is shown applied in the direction of arrows 1910 by vacuum source 1902. Furthermore, a saw mechanism 2302 is shown in ready position to be applied to wafer 400. Saw mechanism 2302 may be any kind of sawing or cutting member, including a saw or other type of blade, a laser, or other cutting or sawing device.

[0200] FIG. 24 shows saw mechanism 2302 being applied to wafer 400 to cut or saw one edge of a die 104a free from wafer 400.

[0201] FIG. 25 shows saw mechanism 2302 being used to saw a second edge of die 104a free from wafer 400.

[0202] As mentioned above, vacuum source 1902 applies a vacuum or suction in the direction of 1910, shown in FIG. 25. According to step 2004 of flowchart 2000 shown in FIG. 20, vacuum source 1902 creates at least a partial vacuum in each of cells 1304 by directing a vacuum or suction along the direction of arrow 1910 through holes 1306 in die receptacle structure 1300. Thus, as shown in FIG. 26, dies are separated from the wafer according to FIG. 11, saw mechanism 2302, and are transferred into the corresponding cell 1304 due to the suction force of vacuum source 1902. Thus, FIG. 26 shows an example implementation of step 2006 of flowchart 2000. For example, as shown in FIG. 26, as die 104a has been freed from wafer 400 by saw mechanism 2302, die 104a has been transferred or drawn into cell 1304a by vacuum source 1902 through hole 1306a. Furthermore, die 104a has become attached in cell 1304a due to adhesive material layer 2102. The process of freeing dies 104 from wafer 400 can be continued until as many dies as desired have been separated from wafer 400, and have been transferred into cells 1304 of die receptacle structure 1300, including some or all dies 104 of wafer 400.

[0203] FIG. 27 shows a plan view of an example wafer portion of wafer 400 that is held by a jig or chuck 1904. As shown in FIG. 27, wafer 400 has been sawed or cut by sawing mechanism 2302 along an X axis, as shown by X axis cuts 2702A and 2702B. Furthermore, an Y axis cut 2704 is shown being made in wafer 400. Cut 2704 has freed die 104A from wafer 400. Thus, as shown in FIG. 26, die 104A is free to transfer into a corresponding cell 1304, assisted by vacuum source 1902. Cuts through wafer 400 can continue to separate the remaining dies 104 of wafer 400, and to transfer the dies 104 into corresponding cells 13Q4 of die receptacle structure 1300.

[0204] Note that dies 104 can be separated from wafer 400 in a number of ways, including by the parallel use of multiple sawing mechanisms 2302.

[0205] In an embodiment, positive pressure is applied to the top surface of the wafer in addition to the suction/vacuum (or negative pressure) applied to the second surface of the die receptacle structure to aid the transfer of dies into the die receptacle structure. FIG. 154 shows an exemplary system having a positive pressure source and a vacuum/suction source, according to an example embodiment of the present invention. As shown in FIG. 154, positive pressure source 15404 exerts a positive pressure on the top surface of wafer 15400. The positive pressure source 15404 could be a mechanical member that is lowered to contact the top surface of wafer 15400 and to apply pressure thereto. Alternatively, positive pressure source 15404 could provide a punching force through the use of a continuous or burst of air or similar type of pressure.

[0206] While the positive pressure source is applying a positive pressure to the top surface of the wafer, the suction/vacuum source applies a negative pressure, described above. The combination of positive pressure and negative pressure causes dies to transfer from wafer 15400 to die receptacle structure 15490.

[0207] In some embodiments, dies 104 can be transferred from a support surface into die receptacle structure 1300. FIG. 28 shows example steps related to a flowchart 2800 for transferring dies from a support structure to die receptacle structure 1300, according to example embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion. Note that in alternative embodiments, the steps shown in FIG. 28 can occur in an order other than that shown.

[0208] FIGs. 29-31 relate to the steps of flowchart 2800. For example, FIG. 29 shows an example of step 2802, where a support structure 404 that attaches dies 104 to a surface thereof is being positioned relative to the first surface of die receptacle structure 1300. Each die attached to support structure 404 is positioned adjacent to a corresponding cell 1304 of die receptacle structure 1300.

[0209] As shown in FIG. 29, dies 104 are attached to support structure 404 and are oriented relative to die receptacle structure 1300, where dies 104 face away from the cells 1304 of die receptacle structure 1300. In alternative embodiments, dies 104 may be positioned on the bottom surface of support structure 404.

[0210] Furthermore, as shown in FIG. 29 and FIG. 30, vacuum source 1902 applies suction, according to step 2804 of flowchart 2800 shown in FIG. 28.

As shown in FIG. 30, support structure 404 has come in contact with the top surface of die receptacle structure 1300. As shown in FIGs. 29 and 30, die receptacle structure 1300 has been modified. In the embodiment of FIGs. 29 and 30, the first surface of die receptacle structure 1300 has sharp edges. As shown in FIG. 29, the edges or portions of die receptacle structure 1300 between cells 1304 are sharp. For example, first and second sharp edges 2904A and 2904 are indicated for a first cell 1304A. As will be shown below, sharp edges 2904 are used to separate dies 104 from support structure 2902.

[0211] Furthermore, as shown in FIG. 29 for support structure 404, support structure 404 has an adhesive surface 2902. Surface 2902 of support structure 404 is coated with an adhesive material that can be used to adhere dies 104 in cells 1304 of die receptacle structure 1300. Note that in an alternative embodiment, cells 1304 can have an adhesive material formed therein, similarly to as that described above for FIGs. 21-27.

[0212] As shown in FIG. 30, vacuum source 1902 applies a suction in the direction of arrows 1910 at a second surface of die receptacle structure 1300.

As a result, at least a partial vacuum exists in each of cells 1304 due to the hole 1306 that corresponds to each of cells 1304. This suction pulls or forces support structure 404 upon sharp edges 2904 of die receptacle structure 1300.

[0213] FIG. 31 shows an example implementation of step 2806 of flowchart 2800, shown in FIG. 28. As shown in FIG. 31, the suction applied by vacuum source 1902 is allowed to cause the sharp edges or portions 2904 of die receptacle structure 1300 around each die 104 of support structure 404 to cut support structure 404 around each die 104. Thus, each die 104 is separated from support structure 404, and is free to remain into the corresponding cell 1304. Thus, as shown in the embodiment of FIG. 31, the adhesive bottom surface of support structure 404 adheres each die in the respective cell 1304.

For example, as shown in FIG. 31, a portion 404A of support structure 404 adheres die 104A in cell 1304A due to the adhesive material on surface 2902 of portion 404A.

[0214] FIG. 32 shows example steps related to a flowchart 3200 for transferring dies from a support structure to a die receptacle structure 1300, according to further embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion.

[0215] FIGs. 33-35 relate to the steps of flowchart 3200 of FIG. 32. FIG. 33 shows an example support structure 404 having a plurality of dies 104 attached thereto. Dies 104 are shown in FIG. 33 attached to the bottom surface of support structure 404 in a die-down or pads-down fashion. In other words, the contact pads of die 104 are on the side of die 104 that is attached to support structure 404. In alternative embodiments, dies 104 may be attached to support structure 404 in a pads-up orientation.

[0216] FIG. 34 shows an implementation of step 3202 of flowchart 3200 shown in FIG. 32. As shown in FIG. 34, the bottom surface of support structure 404 is positioned to be closely adjacent to die receptacle structure 1300 such that each die 104 attached to the bottom surface of support structure 404 is positioned in a corresponding cell 1304 of die receptacle structure 1300.

As shown in FIG. 34, each die 104 attaches to adhesive material layer 2102 that is present in each of cells 1304.

[0217] FIG. 35 shows an implementation example of step 3204 of flowchart 3200 shown in FIG. 32. As shown in FIG. 35, each die 104 of the plurality of dies 104 that were attached to support structure 404 are released from support structure 404. Thus, each die 104 resides in the corresponding cell 1304 of the plurality of cells 1304 of die receptacle structure 1300.

[0218] Dies 104 can be released from support structure 404 in a variety of ways, according to the present invention. For example, adhesive material layer 2102 may comprise a stronger adhesive force than the adhesive force of support structure 404. Thus, once dies 104 become attached to die receptacle structure 1300 due to adhesive material layer 2102, support structure 404 can be withdrawn of peeled from die receptacle structure 1300, leaving dies 104 attached in their corresponding cells 1304. Thus, support structure 404 can merely be moved away from die receptacle structure 1300 to cause dies 104 to be released. Furthermore, as shown in FIGs. 33-35, the vacuum or suction of vacuum source 1902 can be used to aid in holding dies 104 in cells 1304 of die receptacle structure 1300 when support structure 404 is moved away. Thus, vacuum source 1902 is optional in the embodiment related to FIGs. 32-35.

Note that an adhesive material may be additionally applied to the bottom surfaces of dies 104 before positioning dies 104 in cells 1304, instead of, or in addition to, the use of adhesive material layer 2102 in cells 1304.

2.1. 2 Die Transfer onto a Die Plate [0219] According to an embodiment of the present invention, a die plate is used for transferring dies from wafers or support surfaces to substrates or subsequent transfer services. While die receptacle structure 1300 discussed above is also considered a die plate, the die plate described in this subsection does not include cells 1304. Instead, dies 104 are attached to a surface of the die plate, and are positioned over a corresponding hole 1306. Once a die is transferred to the die plate, the die can then be transferred to subsequent, intermediate/transfer surfaces, or to a final surface or structure, such as a substrate.

[0220] FIG. 36 shows an example die plate 3600, according to an example embodiment of the present invention. As shown in FIG. 36, die plate 3600 includes a body 3602. As shown in FIG. 36, body 3602 is substantially planar.

Body 3602 can be manufactured using materials such as those used for body 1302 described above (shown in FIGs. 13A-B), including a metal or combination of metals/alloy, a polymer, a plastic, glass, other materials, and any combination thereof. Furthermore, as shown in FIG. 36, body 3602 has a plurality of openings or holes 3606 formed therethrough. Holes 3606 are open at both the top and bottom planar surfaces of body 3602. Although holes 3606 are shown in FIG. 36 as being substantially round or elliptical, they can have other shapes, including square or rectangular, or other shape.

[0221] FIGS. 37A-E show example schematic views of die plate 3600, according to an example embodiment. For example, FIG. 37A shows a die plate 3600, and shows the outline of a wafer 400 superimposed on top of die plate 3600. FIG. 37B also shows a die plate portion 3710 showing a close-up view of a surface of die plate 3600. As shown for portion 3710, die plate 3606 has a plurality of holes 3606, and in this particular embodiment, includes a plurality of grid lines 3702. Grid lines 3702 can be formed on either or both of the bottom and top surfaces of die plate 3600. Grid lines 3702 can be used to indicate areas for placement of dies 104 on die plate 3600 and/or can be used as guidelines for sawing or otherwise separating dies 104 on die plate 3702. For example, grid lines 3702 can be grooves in the surface of die plate 3600 for an end of a saw blade to pass through. FIG. 37 also shows a plan view of a die plate portion 3720.

[0222] FIG. 38 shows a perspective view of a die plate portion 3800, according to an embodiment of the present invention. As shown in FIG. 38, die plate portion 3800 includes holes 3606, and grid lines 3702, which are shown as grooves in the surface of die plate 3600.

[0223] FIG. 39 shows example steps related to a flowchart 3900 for transferring dies from a support structure to die plate 3600, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion.

[0224] FIGs. 40-42 relate to the steps of flowchart 3900 of FIG. 39. FIG. 40 shows a plurality of dies 104 attached in a pads-down fashion to a bottom surface of a support structure 404. FIG. 40 also shows a cross-sectional view of die plate 3600. As shown in FIG. 40, an adhesive material layer 2102 has been formed on the top surface of die plate 3600. Note that additionally or alternatively, an adhesive material can be applied to the bottom surfaces of dies 104.

[0225] FIG. 41 shows an implementation of step 3902 of flowchart 3900 shown in FIG. 39. As shown in FIG. 41, support structure 404 and die plate 3600 are positioned closely adjacent to each other, such that each die 104 attached to support structure 404 adheres to the top surface of die plate 3600 due to adhesive material layer 2102.

[0226] FIG. 42 shows an example implementation of step 3904 of flowchart 3900 shown in FIG. 39. As shown in FIG. 42, each die 104 is released from support surface 404, and therefore remains attached to die plate 3600. In an embodiment, for example, the adhesive force of adhesive material layer 2102 is stronger than the adhesive force of the bottom surface of support structure 404. Thus, when support structure 404 is moved away from die plate 3600, dies 104 remain attached to die plate 3600. Thus, support structure may be peeled from die plate 3600 to transfer dies 104.

[0227] Note that although a vacuum source, such as vacuum source 1902 described above, is not shown or used in FIGs. 40-42, in an alternative embodiment, a vacuum source 1902 can be used in the current embodiment to aid in transferring dies 104 to die plate 3600.

[0228] In further embodiments, dies 104 of a wafer 400 can be directly transferred to die plate 3600. FIG. 43 shows example steps related to a flowchart 4300 for transferring dies from a wafer to die plate 3600, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion.

[0229] FIGs. 44-46 relate to the steps of flowchart 4300 shown in FIG. 43.

For example, FIG. 44 shows an example wafer having a plurality of dies included therein, being positioned adjacent to a die plate 3600. Note that in an embodiment, wafer 400 has been thinned so that it has a thickness of approximately the thickness of a die. Furthermore, as shown in FIG. 44, an adhesive material layer 2102 has been applied to the top surface of die plate 3600. Note that additionally, or alternatively, an adhesive material may be applied to the bottom surface of wafer 400.

[0230] FIG. 45 shows an example implementation of step 4302 of flowchart 4300 shown in FIG. 43. As shown in FIG. 45, wafer 400 and die plate 3600 are positioned closely adjacent to each other such that wafer 400 adheres to the first surface of die plate 3600. Note that die plate 3600 and wafer 400 are positioned such that each die 104 of wafer 400 covers a corresponding hole 3606 through die plate 3600 at the first or top surface of die plate 3600.

[0231] FIG. 46 shows an example implementation of step 4304 of flowchart 4300 shown in FIG. 43. As shown in FIG. 46, each of dies 104 are scribed/separated from wafer 400 so that they remain attached to the top surface of die plate 3600. For example, as shown in FIGS. 45 and 46, a saw mechanism 2302 can be used to separate the dies 104 of wafer 400. The blade of saw mechanism 4302 may track the grooves or lines of grid 3702 which can be optionally formed in the top surface of die plate 3600. As described above, saw mechanism 2302 can be a saw blade or other cutting device, can be a laser, or any other sawing or cutting device suitable for separating dies from a wafer 400.

2.1. 2.1 Die Transfer onto a Die Plate from Partially Cut Adhesive Surface [0232] FIGS. 171-177 show various views of a transfer of dies to a die plate, and subsequently to one or more substrates, according to embodiments of the present invention. FIG. 171 shows a wafer 400 attached in a pads-up fashion to a surface of a support structure 404. For example, wafer 400 and support structure 400 may be held in a conventional wafer frame or other holding mechanism. As shown in FIG. 171, a first die 104 is being separated from wafer 400. For example, as shown in FIG. 171, a saw mechanism 2302 (or other suitable device or process) can be used to scribe/separate die 104 of wafer 400. Furthermore, saw mechanism 2302 penetrates and cuts/separates a groove depth 17102 of the total thickness 17104 of support structure 404 when separating first die 104a from wafer 400, to form grooves 17106. Groove depth 17102 can be any portion of the thickness 17104 of support structure 404, as required by the particular application. As shown in FIG. 171, groove depth 17102 can be greater than 50% of thickness 17104, including approximately 90% of thickness 17104.

[0233] Note that although FIG. 171 shows dies 104 being separated when grooves 17106 are formed, in another embodiment, dies 104 may already have been separated before grooves 17106 are formed. Thus, in such an embodiment, grooves 17106 may be formed in a subsequent processing step to the actual scribing of wafer 400. Thus, the present application is applicable to using scribed and un-scribed wafers.

[0234] FIG. 172 shows wafer 400 having a plurality of dies 104a-d separated, with grooves 17106a-e formed in support structure 404 around each of the plurality of dies 104. Furthermore, FIG. 172 shows wafer 400 being positioned adjacent to a die plate 3600 in preparation for transfer of dies 104 to die plate 3600. Note that because grooves 17106 penetrate support structure 404 around each die 104, potentially weakening support structure 404, support structure 404 may sag when being positioned adjacent to die plate 3600. Such sagging of support structure 404 may create difficulties in precisely aligning dies 104 over corresponding holes 3606 through die plate 3600. Thus, if groove depth 17102 is great enough to cause significant sagging of support structure 404, a vacuum and/or positive pressure may be used to reduce or eliminate the sagging. For example, FIG. 173 shows a pressure source 17302 used to provide a positive pressure. For example pressure source 17302 provides a gas pressure 17304 directed through holes 3606 of die plate 3600 to reduce sag in support structure 404 when support structure 404 and die plate 3600 are being moved into contact. Alternatively or additionally, a vacuum source may be applied to support structure 404 (e. g., from above support structure 404 in FIG. 173) to provide a vacuum/suction to reduce sag in support structure 404.

[0235] FIG. 174 shows support structure 404 and die plate 3600 positioned closely adjacent to each other such that support structure 404 adheres to the first surface of die plate 3600. Note that die plate 3600 and wafer 400 are positioned such that each of dies 104a-d covers a corresponding hole 3606a-d through die plate 3600 at the first or top surface of die plate 3600.

[0236] FIG. 175 shows a close up view of a die 104a of FIG. 174, where die plate 3600 attaching support structure 404 and dies 104 has been inverted. As shown in FIG. 175, a pin 17502 is inserted in hole 3606a to be used to push/punch die 104a from die plate 3600. FIG. 176 shows pin 17502 moving through hole 3606a of die plate 3600 to contact support structure 404 opposite of die 104a, to push die 104a in contact with a substrate 17602. Pin 17502 separates die 104a from support structure 404 by tearing/ripping support structure 404 around the perimeter of die 104a, such as at perimeter portions 17604a and 17604b in FIG. 175 (an adhesiveness of substrate 17602 may also contribute to this tearing/ripping of support structure 404).

[0237] Note that pin 17502 may be coupled to a pin plate having a plurality of pins 17502 that push/punch a plurality of dies 104 from die plate 3600 in parallel onto the same or multiple substrates. For example, in a multiple substrate embodiment, the substrates may be separate, or joined together in a web of substrates. Further description on example pin plates is provided elsewhere herein.

[0238] FIG. 177 shows die 104a on substrate 17602, having been separated from support structure 404 by pin 17502. As shown in FIG. 177 portion 17702 of support structure 404 remains attached to die 104a. Portion 17702 of support structure 404 helps to protect die 104a from damage due to pin 17502 during transfer of die 104 to substrate 17602. Portion 17702 attached to die 104a can subsequently be removed from die 104a if desired, or can remain on die 104a when the respective tag or other device including substrate 17602 is completed. For example, portion 17702 can remain on die 104a to provide environmental protection for die 104a.

[0239] FIG. 178 shows a flowchart providing steps for transferring dies, according to embodiments of the present invention. For example, FIG. 178 relates to the transfer of dies shown in FIGS. 171-177. Further structural embodiments of the present invention will be apparent to persons skilled in the relevant art (s) based on the following discussion. These steps are described in detail below.

[0240] In step 17802, grooves are formed in a first surface of a support structure that attaches a plurality of dies. For example, the grooves are grooves 17106 formed in support structure 404, as shown in FIGS. 171-176.

Note that the dies attached to the support structure may be separate on the support structure, or included in a wafer, prior to formation of the grooves.

[0241] In step 17804, a second surface of the support structure and a die plate are moved into contact with each other so that the support structure attaches to the die plate. For example, as shown in FIG. 174, the bottom surface of support structure 404 is moved into contact with die plate 3600, to become attached to die plate 3600. Note that in an embodiment, as described above, a positive pressure can be applied to the support structure to reduce sag in the support structure.

[0242] In an embodiment, flowchart 17800 includes step 17806. In step 17806, at least one hole through the die plate is punched through to transfer a corresponding die from the die plate to a destination surface. For example, as shown in FIGS. 175 and 176, pin 17502 passes through hole 3606a to transfer die 104a from die plate 3600 to substrate 17602. Note that in an embodiment, the support structure around the corresponding die is torn to release the die from the support structure. In an embodiment, a portion of the support structure remains attached to the die.

2.1. 2.2 Example Die Plate Embodiments [0243] As described above, FIGS. 37A-E show example schematic views of die plate 3600, according to an illustrative embodiment of the present invention. As described above, a die plate can be made from a variety of materials. In an embodiment, a die plate is made from the same material as a corresponding pin plate is made, or from a material having the same coefficient of thermal expansion (CTE) as a corresponding pin plate, so that the die plate and pin plate will expand and contract uniformly due to changes in temperature. For example, a die plate and corresponding pin plate can be from aluminum. In another example, one of the die plate and corresponding pin plate are made from Kapton, while the other is made from aluminum, because Kapton and aluminum have very similar CTE values. Alternatively, both can be made from Kapton.

[0244] As described above, FIG. 37A shows a die plate 3600, and shows the outline of a wafer 400 superimposed on top of die plate 3600. Die plate 3600 can have any shape and size, as required by a particular application. For example, die plate 3600 shown in FIG. 37A can have a width and length of approximately 254 mm. Wafer 400 can have a diameter of approximately 203 mm, for example. Die plate 3600 can have holes 3606 spaced according to any distances, as required by a particular application. For example, in one embodiment, die plate 3600 can have a hole pattern of 103 x 205 holes spaced apart 2 mm horizontally and 1 mm vertically for a total number of 21,115 holes (e. g. , for rectangular die). Such a pattern can cover a 204 mm x 204 mm pattern (from hole center to hole center).

[0245] FIG. 37C shows a plan view of a die plate portion 3720. Holes 3606 can have any diameter, as required by a particular application. Typically, holes 3606 have a diameter less than or equal to a minimum of the width and length of a corresponding die. For example, hole 3606 shown in FIG. 37C can have a diameter of approximately 0. 584 mm to accommodate a die having a width of approximately 0.949 mm and a length of approximately 1.949 mm.

FIGS. 37D and 37E show cross-sectional views of portions of die plate 3600.

Grooves 3702 can have any widths and depths, as required by a particular application. For example, grooves 3702 shown in FIGS. 37D and 37E can have widths of approximately 0.051 mm and depths of approximately 0.051 mm.

[0246] It is noted that any of the sizes/dimensions, spacings, numbers of holes, etc. , described above are provided for illustrative purposes. It will be apparent to persons skilled in the relevant art (s) that these parameters can be modified as needed for a particular application. For example, these parameters can be modified for particular wafer sizes, die sizes, number of dies to be transferred in parallel, etc.

2.1. 3 Die Transfer from Intermediate Surface to Substrate [0247] According to an embodiment of the present invention, a pin plate is used to transfer dies from a transfer surface to substrates. The pin plate is a plate having a plurality of nails or pins extending therefrom. The transfer surface can be one of the die plate structures described above, including die receptacle structure 1300 or die plate 3600, for example. In this manner, a large number of electronic devices can be manufactured, including RF ID tags.

[0248] The pin plate of the present invention can be referred to by a variety of other names, including nail plate,"bed-of-nails,"and punch plate.

[0249] FIG. 47 shows an example pin plate 4700, according to an example embodiment of the present invention. As shown in FIG. 47, pin plate 4700 comprises a body 4702. Body 4702 is shown in FIG. 47 as a substantially planar structure, but can have other shapes. Furthermore, while the planar surfaces of body 4702 are shown to be square or rectangular in shape, body 4702 can have other shapes, including round, elliptical, hexagonal, cross- shaped, and diamond shaped. As shown in FIG. 47, body 4702 has a plurality of nails or pins 4704 extending from a first surface thereof. Pins 4704 are typically arranged in an array of rows and columns of pins. Pin plate 4700 can be made from any number of materials, including a metal or combination of metals/alloy, a polymer, a plastic, glass, another material, and any combination thereof.

[0250] FIG. 48 shows example views of pin plate 4700, according to example embodiments of the present invention. For example, a pin-side or first surface view of pin plate 4700 is shown as view 4810. A side view of pin plate 4700 is shown as view 4820. A back, non-pin-side, or second surface view of pin plate 4700 is shown as view 4822. It is noted that in the embodiment of FIG. 48, as shown in view 4820, pin plate 4700 can have a centrally located plateau portion, located on the pin-side of pin plate 4700, on which pins 4704 are formed.

[0251] FIG. 49 shows a close-up view 4910 and close-up pin view 4920.

FIGs. 48 and 49 both show example dimensional values for various dimensions of pin plate 4700, according to example embodiments of the present invention.

[0252] FIG. 50 shows example steps related to a flowchart 5000 for transferring dies from a die plate to substrates of a web, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion [0253] FIGs. 51-57 relate to the steps of flowchart 5000. For example, FIG. 51 shows an example die receptacle structure 1300 that has an array of cells 1304 formed in a first or bottom surface. Furthermore, each cell 1304 includes a corresponding hole 1306 formed through die receptacle structure 1300. Furthermore, each cell 1304 holds a corresponding die 104 therein.

Thus, FIG. 51 shows an example implementation of step 5010 of flowchart 5000 shown in FIG. 50.

[0254] FIG. 51 also shows an example implementation of step 5020 of flowchart 5000 shown in FIG. 50. As shown in FIG. 51, a web 808 of substrates 116 is positioned relative to the first surface of die receptacle structure 1300, such that cells 1304 in die receptacle structure 1300 are positioned adjacent to corresponding die mount areas of a substrate 116 of web 808. Thus, for example, FIG. 51 shows a cell 1304, in which a die 104A resides, that is positioned closely adjacent to substrate 116A.

[0255] FIG. 52 shows an example implementation of step 5030, of flowchart 5000, shown in FIG. 50. As shown in FIG. 52, pin plate 4700 is applied to the second surface of die receptacle structure 1300, such that each pin 4704 of pin plate 4700 extends through a corresponding hole 1306 of die receptacle structure 1300. Thus, holes 1306 are punched through by corresponding pins 4704 to transfer a die 104 from each cell 1304 to the corresponding die contact area of a substrate 116 of web 808. For example, as shown in FIG. 52, pin 4704A extends through hole 1306A to punch die 104A from cell 1304A onto the contact area of substrate 116A. As shown in FIG. 52, contact pads 204A and 204B of die 104A are coupled with corresponding contact areas 210A and 210B of substrate 116A.

[0256] FIG. 53 shows an example perspective view of dies 104 being applied to substrates 116 by corresponding pins 4704. Body 4702 of pin plate 4700 is not shown in FIG. 53, for ease of illustration.

[0257] Flowchart 5000 of FIG. 50 may include the additional step of curing an adhesive material to adhere die 104 to the corresponding contact area of the respective substrate 116. For example, as shown in FIG. 54, an adhesive material 5202A may be cured to bond die 104A to the contact pads of substrate 116A. In the example of FIG. 54, adhesive material 5202 is a light- curable adhesive material. Thus, a light source 5402 may be applied to cause adhesive material 5202 to be cured. For example, adhesive material 5202 may be ultraviolet (IJV) light-curable, and therefore light source 5402 may be an UV light source. Adhesive material 5202 may be cured in other ways, alternatively. For example, adhesive material can be a glue, epoxy, laminate, or any other adhesive material otherwise known or described elsewhere herein.

[0258] To aid in the curing of adhesive material 5202 when adhesive material 5202 is light-curable, the contact areas 210 on substrate 116 may have holes formed through them so that light can pass more easily through. For example, as shown on FIG. 54, light source 5402 is applied to a bottom side of web 808, which is a side opposite of that to which dies 104 are being applied.

Conventionally, light of a light source 5402 that passes through web 808 could be blocked by the conductive material of contacts 210, which may be metal, for example. Thus, for example, as shown in FIG. 55, contact areas 210 can have holes formed through them in an area where adhesive material 5202 is applied, so that a light 5404 from light source 5402 can pass through, and cause the curing of adhesive material 5202. FIG. 55 shows an example of -holes 5502 in contact areas 210, according to an embodiment of the present invention. FIG. 56 shows another example of holes 5502 formed in contact areas 210, in an actual implementation. FIG. 56 shows an expanded view of an actual contact area implementation, where each contact area 210 has a pair of holes 5502A and 5502B formed therein for the passage of ultraviolet light to cure adhesive material 5202.

[0259] Flowchart 5000 of FIG. 50 can include the additional step 5050 where pin plate 4700 is withdrawn or retracted from die receptacle structure 1300, leaving dies 104 attached to substrates 116. Subsequent to this, pin plate 4700, die receptacle structure 1300, and web 808 can be moved or incremented relative to each other, so that additional dies can be punched from die receptacle structure 1300 onto substrates 116 of web 808. After one or more iterations, die receptacle structure 1300 may become emptied of dies 104. At this time, a new die receptacle structure 1300 filled with dies 104 can be used to replace the emptied die receptacle structure 1300, and the process can be continued.

[0260] In step 5060, a determination is made whether additional die remain to be transferred from the die plate. If die remain to be transferred, operation proceeds to step 5080. If no die remain to be transferred, operation proceeds to step 5070.

[0261] In step 5080, the die plate and/or the substrate web can be moved or incremented relative to each other, so that additional dies can be transferred from the die plate onto substrates of web. In an alternate embodiment, the pin plate and/or substrate web are incremented relative to each other. In a third embodiment, the die plate, pin plate, and substrate web are all incremented relative to each other. Operation than proceed to step 5030.

[0262] After one or more iterations, the die plate may become emptied of dies 104 or the maximum number of dies 104 that can be transferred from the die plate may have been reached. When a die plate is exhausted, in step 5070, the die plate is removed.

[0263] In step 5075, a new die plate filled with dies 104 is received to replace the exhausted die plate. Operation then proceeds to step 5020.

[0264] According to embodiments of the present invention, pin plate 4700 can have any number of pins, and any spacing of pins required. For example, pin plate 4700 can have an array of pins 4704 configured to punch out the appropriate number of dies 104 onto the corresponding number of substrates 116 of a web 808, at the correct spacing of the substrates 116 in web 808.

Thus, for a given size of a die receptacle structure 1300 or die plate 3600, a pin plate 4700 can have a variety of sizes. For example, FIG. 58 shows a variety of substrate portion sizes of a web 808, and a corresponding pin plate 5804 that can be used to transfer dies 104 from a die plate 3600 or die receptacle structure 1300 onto the substrates thereof. For example, a web portion 4802 is shown that is a 2x2 array of substrates 116. Thus, a corresponding pin plate 5804, having an appropriately spaced array of four pins extending therefrom, can be used to punch dies onto web portion 5802.

[0265] FIG. 58 also shows a web portion 5806 that comprises a 3x3 array of substrates 116. Thus, a pin plate 5808, having an array of nine pins extending therefrom, can be used to transfer dies thereto.

[0266] FIG. 58 also shows a web portion 5810 having a 4x4 array of substrates 116. Thus, a pin plate 5812, having an array of 16 pins thereon, can be used to transfer dies 104 to web portion 5810.

[0267] FIG. 58 also shows a web portion 5814 having a 5x5 array of substrates 116. Thus, a pin plate 5816, having an array of 25 pins thereon, can be used to transfer dies 104 to web portion 5814.

[0268] FIG. 58 also shows a web portion 5818 having a 6x6 array of substrates 116. Thus, a pin plate 5820, having an array of 36 pins thereon, can be used to transfer dies 104 to web portion 5818.

[0269] FIG. 58 also shows a web portion 5822 having a 7x7 array of substrates 116 therein. Thus, a pin plate 5824, having an array of 49 pins thereon, can be used to transfer dies 104 to web portion 5822.

[0270] FIG. 59 shows additional substrate arrays and corresponding pin plates for transferring dies thereto, of various sizes.

[0271] FIGs. 60 and 61 show various web portions having different sized arrays of substrates that require pin plates of various sizes, according to further embodiments of the present invention.

2.1. 3.1 Multi-Head Die Transfer [0272] The present invention is directed to the assembly of large numbers of RFID tags or other electronic devices. Thus, the die plate/die receptacle structures described above are designed to contain large numbers of dies that may be transferred to substrates in large quantities. This subsection discusses the transfer of dies from these structures to webs of substrates, using multiple die transfer heads. In other words, multiple die plates/die receptacle structures are simultaneously used to transfer dies to substrates of the web.

[0273] Any number of pin plates/die receptacle structures can be used in parallel to increase a transfer rate. For example, FIG. 62 shows an example embodiment for using four pin plates 4700 in parallel. FIG. 62 shows front and back perspective views of a chip assembly fixture 6200. Chip assembly fixture 6200 includes a die plate frame 6202, a pin plate 4700, and four die receptacle structures 1300a-d. As is apparent from FIG. 62, pin plate 4700 can be applied to die receptacle structures 1300a-d sequentially. Alternatively, four pin plates 4700a-d can be applied in parallel to the four die receptacle structures 1300a-d to transfer dies simultaneously. Thus, in the current example, a speed of die transfer can be increased by a factor of four, and in other embodiments, can be increased by other factors. Furthermore, larger numbers of dies can be transferred simultaneously to larger web sizes.

[0274] FIG. 63 shows an example front view of die plate frame 6202 and a side cross-sectional view of chip assembly fixture 6200.

[0275] FIGs. 64a-b show example cross-sectional views of a pin 4704 of a pin plate 4700 being inserted into a hole 1306 of a die receptacle structure 1300.

As shown in FIGs. 64a-b, pin 4704 extends through hole 1306, reaching a die 104 located or residing in a cell 1304 of die receptacle structure 1300. Pin 4704 can therefore be used to move die 104 from cell 1304 to a substrate.

FIGs. 64a-b show example dimensions for these elements of pin plate 4700 and die receptacle structure 1300, according to example embodiments of the present invention. Furthermore, as shown in FIGs. 64a-b, hole 1306 does not have to be uniformly thick, but can have a larger size where pin 4704 is inserted as compared to the opposite side of die receptacle structure 1300 at cell 1304.

[0276] FIGs. 65a-b show even further detail of die 104 located in cell 1304 of FIGs. 64a-b, according to an embodiment of the present invention. For example, note that the dimensions of cell 1304 do not necessarily have to be uniform from the bottom of cell 1304 to the top of cell 1304. For example, as shown in FIGs. 65a-b, the size of cell 1304 is smaller at the base of cell 1304 than it is at the opening of cell 1304 to the top surface of die receptacle structure 1300. For example, this may aid in allowing die 104 to be pushed from cell 1304 by pin 4704. Example dimensions related to these elements are shown in FIGs. 65a-b for illustrative purposes.

[0277] FIG. 66 shows systems related to a multi-head assembly process and system according to embodiments of the present invention. For example, FIG.

66 shows a pair of die assembly carousels 6620a and 6620b. Referring to die assembly carousel 6620a for illustrative purposes, a die assembly carousel 6620 includes a plurality of arms 6612, a carousel pivot point 6610, and a plurality of carousel heads 6604. In the example shown in FIG. 66, die assembly carousel 6620a includes three arms 6612a-c that each have a first end coupled to carousel pivot point 6610. At a second end of each of arms 6612a-c, is attached a corresponding one of carousel heads 6604a-c.

[0278] In embodiments, a die assembly carousel 6620a can have any number of carousel arms 6612 and corresponding carousel heads 6604. Furthermore, as shown in FIG. 66, each carousel head 6604 supports a plurality of die transfer heads 6602. For example, as shown in FIG. 66, a carousel head 6604a supports a first die transfer head 6602a, a second die transfer head 6602b, and a third die transfer head 6602c. In embodiments of the present invention, a carousel head 6604 can support any number of die transfer heads 6602. In embodiments of the present invention, die transfer heads 6602 can include any type of die plate or die frame described elsewhere herein that hold dies, including die receptacle structure 1300 and/or die plate 3600. Die transfer heads 6602 can also include a pin plate 4700, or similar device, to transfer the dies from the corresponding die plate or die frame.

[0279] During assembly of tags or other electronic devices, a die assembly carousel 6620 can sequentially supply carousel heads 6604 to the assembly system so that the system will have access to a plurality of die transfer heads 6602. The assembly system transfers dies from the die transfer heads 6602 of a particular carousel head 6604 in parallel to substrates of a web. Once the die transfer heads 6602 of a particular carousel head 6604 are exhausted of dies, die carousel 6620 can rotate around carousel pivot point 6610 to supply a second plurality of die transfer heads 6602 on a subsequent carousel head 6604. This process may be continued until the entire die assembly carousel 6620 is depleted of dies substantially or entirely. At this point, a subsequent die assembly carousel 6620 may be used by the system, while the depleted die carousel is disposed of, or is refilled with dies. Thus, in the example of FIG.

66, when die carousel 6620a is depleted of dies, die carousel 6620a can be retracted, while die assembly carousel 6620b is inserted into the tag assembly system.

[0280] Also as shown in FIG. 66, die assembly carousels 6620 can be stored in a stack, such as die carousel stack 6630. As shown in the example of FIG.

66, die carousel stack includes a first die assembly carousel 6620a, a second die assembly carousel 6620b, and a third die assembly carousel 6620c. In embodiments of the present invention, a die carousel stack 6630 can include any number of die assembly carousels 6620.

[0281] As described above, die assembly carousel 6620 can be used to transfer dies from die transfer heads 6602 to substrates. For example, FIG. 67 shows an example web 6700, which is an example of a web 808 described above. As shown in FIG. 67, web 6700 comprises a large number of individual substrates 116 that in the present example have a dimension of. 2 inches by. 2 inches square. As shown in FIG. 67, a carousel head 6620 that supports three die transfer heads 6602 populated with dies 104 can be used to transfer dies 104 to the substrates 116 of web 6700. As shown in FIG. 67, a carousel head 6604 can support die transfer heads 6602a, 6602b, and 6602c in the example positions over web 6700 shown in FIG. 67. In other words, die transfer heads 6602a-c can transfer dies to the portions of web 6700 that lie adjacent to them, or as shown in FIG. 67, are underneath their positions. The dies may be transferred from die transfer heads 6602 in parallel, in any numbers of one or more.

102821 For example, FIG. 68 shows example pin plate 6800, which can be used to transfer dies from the die transfer head 6602 to web 6700 as shown in FIG. 67. With the example pin plate 6800 as shown in FIG. 68 has 2500 pins 4704 extending therefrom. Thus, pin plate 6800 can transfer 2500 dies 104 simultaneously from die transfer head 6602 shown in FIG. 67. The pins 4704 of pin plate 6800 shown in FIG. 68 are appropriately positioned or spaced so that they can punch dies onto a substrate 116 having dimensions of. 2 inches by. 2 inches, as shown for web 6700 shown in FIG. 67. For example, as shown in FIG. 68, pins 4704 are spaced or have a pitch of. 2 inches. Thus, pin plates 6800 can be applied to die transfer heads 6602a-c in FIG. 67 to transfer dies to web 6700 in great numbers.

[0283] After die plate 6800 has been applied to each of die transfer heads 6602a-c, web 6700 can be shifted, moved, or incremented so that a next set of substrates 116 of web 6700 are positioned adjacent to each die transfer head 6602. Thus, for example, as shown in FIG. 67, web 6700 may be moved in the direction of arrow 6710 by a distance proportional to the width of a coverage area of a die transfer head 6602 to move empty substrates 116 adjacent to die transfer heads 6602. Then, die plate 6800 may be applied to each of die transfer head 6602a-c in parallel or in series to transfer dies 104 to the empty substrates. Die plates 6800 may transfer 1 out of every N dies from a die transfer head 6602 in a single iteration, where N is any integer. This process can be continued, where web 6700 is periodically moved in the direction of arrow 6710, while dies 104 are transferred from each die transfer head 6602 by pin plates 6800. Once die transfer heads 6602 are depleted of dies, a new carousel head 6604 can be shifted over web 6700 by carousel 6620, so that a complete new set of dies are present for transfer to web 6700.

[0284] In this manner, very large numbers of dies 104 can be transferred to substrates 116 of a web 6700. For example, if each of die transfer heads 6602 contain 36,450 dies 104 each, and each of pin plates 6800 include 2500 pins 4704, large number of dies 104 can be transferred. In embodiments, 8,748 dies can be transferred per second, which is equal to 524, 880 dies transferred per minute, which is equal to 31,492, 800 dies transferred per hour. Thus, in a current embodiment, almost 32 million RFID tags can be assembled each hour.

[0285] The following paragraphs show numerous more embodiments for multi-head die transfer. For example, various web sizes are shown for web 808, as well as correspondingly sized pin plates 4700. Each of these embodiments allows for assembly of large numbers of RFID tags or other electronic devices.

[0286] FIGS. 69-71 relate to the multi-head transfer of dies 104 to a web comprising a plurality of. 39"by 39"substrates 116, according to an example embodiment of the present invention. FIG. 69 shows an example web 6900 that includes a 75 by 75 array of the. 39"by. 39"inch substrates. As shown in FIG. 69, die transfer heads 6602a-c are positioned over different locations of web 6900, so that all substrates along the entire width or Y-axis of web 6900 can be covered. FIG. 70 shows a portion 7000 of web 6900 that can be covered by one of die transfer heads 6602. Portion 7000 is a 25 by 25 array of substrates. FIG. 71 shows an example pin plate 7100 having 625 pins to cover each substrate 116 of portion 7000. As shown in FIG. 71, pins 4704 are spaced, or have a pitch of. 39 inches. Thus, by action of one or more pin plates 7100 on die plates 6202a-c, and by periodically incrementing or moving web 6900 along the direction of the length of web 6900 (i. e. , X-axis), all substrates of web 6900 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 6900 having a size equal to that of portion 7000 can be filled with dies by a single punch of pin plate 7100. Example die transfer rates are shown in FIGS. 69 and 70 for the current embodiment.

[0287] FIGS. 72-74 relate to the multi-head transfer of dies 104 to a web comprising a plurality of. 59" by. 59" substrates 116, according to an example embodiment of the present invention. FIG. 72 shows an example web 7200 that includes a 48 by 48 array of the. 59" by. 59" inch substrates. As shown in FIG. 72, die transfer heads 6602a-c are positioned over different locations of web 7200, so that all substrates along the entire width or Y-axis of web 7200 can be covered. FIG. 73 shows a portion 7300 of web 7200 that can be covered by one of die transfer heads 6602. Portion 7300 is a 16 by 16 array of substrates. FIG. 74 shows an example pin plate 7400 having 256 pins to cover each substrate 116 of portion 7300. As shown in FIG. 74, pins 4704 are spaced, or have a pitch of. 59 inches. Thus, by action of one or more pin plates 7400 on die plates 6202a-c, and by periodically incrementing or moving web 7200 along the direction of the length of web 7200 (i. e. , X-axis), all substrates of web 7200 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 7200 having a size equal to that of portion 7300 can be filled with dies by a single punch of pin plate 7400. Example die transfer rates are shown in FIGS. 72 and 73 for the current embodiment.

[0288] FIGS. 75-77 relate to the multi-head transfer of dies 104 to a web comprising a plurality of. 79" by. 79" substrates 116, according to an example embodiment of the present invention. FIG. 75 shows an example web 7500 that includes a 36 by 36 array of the. 79" by. 79" inch substrates. As shown in FIG. 75, die transfer heads 6602a-c are positioned over different locations of web 7500, so that all substrates along the entire width or Y-axis of web 7500 can be covered. FIG. 76 shows a portion 7600 of web 7500 that can be covered by one of die transfer heads 6602. Portion 7600 is a 12 by 12 array of substrates. FIG. 77 shows an example pin plate 7700 having 144 pins to cover each substrate 116 of portion 7600. As shown in FIG. 77, pins 4704 are spaced, or have a pitch of. 79 inches. Thus, by action of one or more pin plates 7700 on die plates 6202a-c, and by periodically incrementing or moving web 7500 along the direction of the length of web 7500 (i. e. , X-axis), all substrates of web 7500 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 7500 having a size equal to that of portion 7600 can be filled with dies by a single punch of pin plate 7700. Example die transfer rates are shown in FIGS. 75 and 76 for the current embodiment.

[0289] FIGS. 78-80 relate to the multi-head transfer of dies 104 to a web comprising a plurality of. 98"by. 98"substrates 116, according to an example embodiment of the present invention. FIG. 78 shows an example web 7800 that includes a 30 by 30 array of the. 98" by. 98" inch substrates. As shown in FIG. 78, die transfer heads 6602a-c are positioned over different locations of web 7800, so that all substrates along the entire width or Y-axis of web 7800 can be covered. FIG. 79 shows a portion 7900 of web 7800 that can be covered by one of die transfer heads 6602. Portion 7900 is a 10 by 10 array of substrates. FIG. 80 shows an example pin plate 8000 having 100 pins to cover each substrate 116 of portion 7900. As shown in FIG. 80, pins 4704 are spaced, or have a pitch of. 98 inches. Thus, by action of one or more pin plates 8000 on die plates 6202a-c, and by periodically incrementing or moving web 7800 along the direction of the length of web 7800 (i. e. , X-axis), all substrates of web 7800 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 7800 having a size equal to that of portion 7900 can be filled with dies by a single punch of pin plate 8000. Example die transfer rates are shown in FIGS. 78 and 79 for the current embodiment.

[0290] FIGS. 81-83 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 1. 18" by 1. 18" substrates 116, according to an example embodiment of the present invention. FIG. 81 shows an example web 8100 that includes a 24 by 24 array of the 1. 18"by 1. 18"inch substrates.

As shown in FIG. 81, die transfer heads 6602a-c are positioned over different locations of web 8100, so that all substrates along the entire width or Y-axis of web 8100 can be covered. FIG. 82 shows a portion 8200 of web 8100 that can be covered by one of die transfer heads 6602. Portion 8200 is a 8 by 8 array of substrates. FIG. 83 shows an example pin plate 8300 having 64 pins to cover each substrate 116 of portion 8200. As shown in FIG. 83, pins 4704 are spaced, or have a pitch of 1.18 inches. Thus, by action of one or more pin plates 8300 on die plates 6202a-c, and by periodically incrementing or moving web 8100 along the direction of the length of web 8100 (i. e. , X-axis), all substrates of web 8100 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 8100 having a size equal to that of portion 8200 can be filled with dies by a single punch of pin plate 8300. Example die transfer rates are shown in FIGS. 81 and 82 for the current embodiment.

[0291] FIGS. 84-86 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 1. 38"by 1. 38" substrates 116, according to an example embodiment of the present invention. FIG. 84 shows an example web 8400 that includes a 21 by 21 array of the 1. 38" by 1. 38" inch substrates.

As shown in FIG. 84, die transfer heads 6602a-c are positioned over different locations of web 8400, so that all substrates along the entire width or Y-axis of web 8400 can be covered. FIG. 85 shows a portion 8500 of web 8400 that can be covered by one of die transfer heads 6602. Portion 8500 is a 7 by 7 array of substrates. FIG. 86 shows an example pin plate 8600 having 49 pins to cover each substrate 116 of portion 8500. As shown in FIG. 86, pins 4704 are spaced, or have a pitch of 1.38 inches. Thus, by action of one or more pin plates 8600 on die plates 6202a-c, and by periodically incrementing or moving web 8400 along the direction of the length of web 8400 (i. e. , X-axis), all substrates of web 8400 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 8400 having a size equal to that of portion 8500 can be filled with dies by a single punch of pin plate 8600. Example die transfer rates are shown in FIGS. 84 and 85 for the current embodiment.

[0292] FIGS. 87-89 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 1. 57" by 1. 57" substrates 116, according to an example embodiment of the present invention. FIG. 87 shows an example web 8700 that includes an 18 by 18 array of the 1. 57" by 1. 57" inch substrates.

As shown in FIG. 87, die transfer heads 6602a-c are positioned over different locations of web 8700, so that all substrates along the entire width or Y-axis of web 8700 can be covered. FIG. 88 shows a portion 8800 of web 8700 that can be covered by one of die transfer heads 6602. Portion 8800 is a 6 by 6 array of substrates. FIG. 89 shows an example pin plate 8900 having 36 pins to cover each substrate 116 of portion 8800. As shown in FIG. 89, pins 4704 are spaced, or have a pitch of 1.57 inches. Thus, by action of one or more pin plates 8900 on die plates 6202a-c, and by periodically incrementing or moving web 8700 along the direction of the length of web 8700 (i. e. , X-axis), all substrates of web 8700 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 8700 having a size equal to that of portion 8800 can be filled with dies by a'single punch of pin plate 8900. Example die transfer rates are shown in FIGS. 87 and 88 for the current embodiment.

[0293] FIGS. 90-92 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 1. 77" by 1. 77" substrates 116, according to an example embodiment of the present invention. FIG. 90 shows an example web 9000 that includes a 15 by 15 array of the 1. 77" by 1. 77" inch substrates.

As shown in FIG. 90, die transfer heads 6602a-c are positioned over different locations of web 9000, so that all substrates along the entire width or Y-axis of web 9000 can be covered. FIG. 91 shows a portion 9100 of web 9000 that can be covered by one of die transfer heads 6602. Portion 9100 is a 5 by 5 array of substrates. FIG. 92 shows an example pin plate 9200 having 25 pins to cover each substrate 116 of portion 9100. As shown in FIG. 92, pins 4704 are spaced, or have a pitch of 1.77 inches. Thus, by action of one or more pin plates 9200 on die plates 6202a-c, and by periodically incrementing or moving web 9000 along the direction of the length of web 9000 (i. e. , X-axis), all substrates of web 9000 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 9000 having a size equal to that of portion 9100 can be filled with dies by a single punch of pin plate 9200. Example die transfer rates are shown in FIGS. 90 and 91 for the current embodiment.

[0294] FIGS. 93-95 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 1. 97" by 1. 97" substrates 116, according to an example embodiment of the present invention. FIG. 93 shows an example web 9300 that includes a 15 by 15 array of the 1. 97" by 1. 97" inch substrates.

As shown in FIG. 93, die transfer heads 6602a-c are positioned over different locations of web 9300, so that all substrates along the entire width or Y-axis of web 9300 can be covered. FIG. 94 shows a portion 9400 of web 9300 that can be covered by one of die transfer heads 6602. Portion 9400 is a 5 by 5 array of substrates. FIG. 95 shows an example pin plate 9500 having 25 pins to cover each substrate 116 of portion 9400. As shown in FIG. 95, pins 4704 are spaced, or have a pitch of 1.97 inches. Thus, by action of one or more pin plates 9500 on die plates 6202a-c, and by periodically incrementing or moving web 9300 along the direction of the length of web 9300 (i. e. , X-axis), all substrates of web 9300 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 9300 having a size equal to that of portion 9400 can be filled with dies by a single punch of pin plate 9500. Example die transfer rates are shown in FIGS. 93 and 94 for the current embodiment.

[0295] FIGS. 96-98 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 2. 17" by 2. 17" substrates 116, according to an example embodiment of the present invention. FIG. 96 shows an example web 9600 that includes a 12 by 12 array of the 2. 17" by 2. 17" inch substrates.

As shown in FIG. 96, die transfer heads 6602a-c are positioned over different locations of web 9600, so that all substrates along the entire width or Y-axis of web 9600 can be covered. FIG. 97 shows a portion 9700 of web 9600 that can be covered by one of die transfer heads 6602. Portion 9700 is a 4 by 4 array of substrates. FIG. 98 shows an example pin plate 9800 having 16 pins to cover each substrate 116 of portion 9700. As shown in FIG. 98, pins 4704 are spaced, or have a pitch of 2.17 inches. Thus, by action of one or more pin plates 9800 on die plates 6202a-c, and by periodically incrementing or moving web 9600 along the direction of the length of web 9600 (i. e., X-axis), all substrates of web 9600 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 9600 having a size equal to that of portion 9700 can be filled with dies by a single punch of pin plate 9800. Example die transfer rates are shown in FIGS. 96 and 97 for the current embodiment.

[0296] FIGS. 99-101 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 2. 36" by 2. 36" substrates 116, according to an example embodiment of the present invention. FIG. 99 shows an example web 9900 that includes a 12 by 12 array of the 2. 36" by 2. 36" inch substrates.

As shown in FIG. 99, die transfer heads 6602a-c are positioned over different locations of web 9900, so that all substrates along the entire width or Y-axis of web 9900 can be covered. FIG. 100 shows a portion 10000 of web 9900 that can be covered by one of die transfer heads 6602. Portion 10000 is a 4 by 4 array of substrates. FIG. 101 shows an example pin plate 10100 having 16 pins to cover each substrate 116 of portion 10000. As shown in FIG. 101, pins 4704 are spaced, or have a pitch of 2.36 inches. Thus, by action of one or more pin plates 10100 on die plates 6202a-c, and by periodically incrementing or moving web 9900 along the direction of the length of web 9900 (i. e. , X- axis), all substrates of web 9900 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 9900 having a size equal to that of portion 10000 can be filled with dies by a single punch of pin plate 10100. Example die transfer rates are shown in FIGS. 99 and 100 for the current embodiment.

[0297] FIGS. 102-104 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 2. 76" by 2. 76" substrates 116, according to an example embodiment of the present invention. FIG. 102 shows an example web 10200 that includes a 9 by 9 array of the 2. 76" by 2. 76" inch substrates.

As shown in FIG. 102, die transfer heads 6602a-c are positioned over different locations of web 10200, so that all substrates along the entire width or Y-axis of web 10200 can be covered. FIG. 103 shows a portion 10300 of web 10200 that can be covered by one of die transfer heads 6602. Portion 10300 is a 3 by 3 array of substrates. FIG. 104 shows an example pin plate 10400 having 9 pins to cover each substrate 116 of portion 10300. As shown in FIG. 104, pins 4704 are spaced, or have a pitch of 2.76 inches. Thus, by action of one or more pin plates 10400 on die plates 6202a-c, and by periodically incrementing or moving web 10200 along the direction of the length of web 10200 (i. e. , X- axis), all substrates of web 10200 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 10200 having a size equal to that of portion 10300 can be filled with dies by a single punch of pin plate 10400. Example die transfer rates are shown in FIGS. 102 and 103 for the current embodiment.

[0298] FIGS. 105-107 relate to the multi-head transfer of dies 104 to a web comprising a plurality of 3. 94" by 3. 94" substrates 116, according to an example embodiment of the present invention. FIG. 105 shows an example web 10500 that includes a 6 by 6 array of the 3. 94" by 3. 94" inch substrates.

As shown in FIG. 105, die transfer heads 6602a-c are positioned over different locations of web 10500, so that all substrates along the entire width or Y-axis of web 10500 can be covered. FIG. 106 shows a portion 10600 of web 10500 that can be covered by one of die transfer heads 6602. Portion 10600 is a 2 by 2 array of substrates. FIG. 107 shows an example pin plate 10700 having 4 pins to cover each substrate 116 of portion 10600. As shown in FIG. 107, pins 4704 are spaced, or have a pitch of 3.94 inches. Thus, by action of one or more pin plates 10700 on die plates 6202a-c, and by periodically incrementing or moving web 10500 along the direction of the length of web 10500 (i. e. , X- axis), all substrates of web 10500 can have dies 104 transferred thereto by one of die transfer heads 6602a-c. All substrates 116 of a portion of web 10500 having a size equal to that of portion 10600 can be filled with dies by a single punch of pin plate 10700. Example die transfer rates are shown in FIGS. 105 and 106 for the current embodiment.

2.1. 3.2 Die Transfer Using Interlocking Geometric Shapes [0299] As described in the preceding section, a multi-head transfer system using multiple die transfer heads 6602 is used to transfer dies. Although die transfer heads 6602 are shown in the figures referenced above as having rectangular coverage areas on a web, die transfer heads 6602 can be formed to have other coverage areas or patterns. According to embodiments of the present invention, die transfer heads 6602 can be used that transfer dies to geometric, self-interlocking patterns of substrates on the web. These geometric, self-interlocking substrate array patterns can be formed in a variety of shapes, including a square, a rectangle, a hexagon, a"cross"shape, and a diamond shape. Furthermore, in embodiments, combinations of these can be used. Other combinations of shapes are possible, including interlocking octagon and square shapes, for example.

[0300] In the following subsection, multi-head die transfer is further enhanced through the use of interlocking geometric shapes. In other words, pin plates are formed that have arrays of pins formed thereon that are laid out according to geometric shapes that can interlock with each other. This is used to enhance the number of dies that are punched by the pin plates from die plates onto webs of substrate, or directly from wafers onto the web of substrates.

Using geometric shapes that interlock enhances the number of dies that are transferred over the number of dies that are transferred using substantially square or rectangle geometric shapes, particularly when large numbers of dies are transferred simultaneously from a wafer or a die plate.

[0301] Dies of a wafer within a geometric pattern are transferred, while those outside the pattern may not be transferred. Note that dies of a wafer outside of the selected geometric pattern that are unused during the die transfer process can used in other ways. For example, they can be collected and placed into die receptacle structures for subsequent transfer to substrates, and/or can be used to replace defective dies that have been attached to substrates, etc.

[0302] For example, FIGS. 108a and 108b show some example geometric shapes for pin plates, according to the embodiments of the present invention.

For example, FIG. 108a shows a first geometric substrate pattern 10802 and a corresponding pin array pattern 10804. When pin array pattern 10804 of a pin plate is applied to either a wafer or to a die plate filled with dies to transfer the dies to a web of substrates, pin array pattern 10804 will transfer dies to an array of substrates on the web in the pattern shown as geometric substrate pattern 10802. In other words, each substrate of an array of substrates on the web shaped as geometric substrate pattern 10802 will receive a corresponding die.

[0303] In another example, FIG. 108a shows a second geometric substrate pattern 10806 and a corresponding pin array pattern 10808. When pin array pattern 10808 of a pin plate is applied to a die plate full of dies or directly to a wafer, it will transfer dies to substrates on a web that are in a pattern of geometric substrate pattern 10806. In other words, each substrate in the pattern of geometric substrate pattern 10806 will receive a die 104 during the transfer. This goes for the other geometric substrate patterns in corresponding pin array patterns shown in FIGs. 108a-b. For example, as shown in FIG.

108a, geometric substrate pattern 10810 corresponds to pin array pattern 10812. Geometric substrate pattern 10814 corresponds to pin array pattern 10816. Geometric substrate pattern 10818 corresponds to pin array pattern 10820. Geometric substrate pattern 10822 corresponds to pin array pattern 10824. As shown in FIG. 108b, geometric substrate pattern 10826 corresponds to pin array pattern 10828. Geometric substrate pattern 10830 corresponds to pin array pattern 10832.

[0304] Using the geometric substrate patterns and corresponding pin array patterns described above, and other patterns that would be known or apparent to persons skilled in the relevant arts from the teachings herein, dies may be transferred to substrates in great quantities. For example, FIG. 109 shows die transfer rates for the various geometric substrate patterns shown in FIGS. 108a and 108b. For illustrative purposes, it is assumed that each geometric substrate pattern can be filled in 1.0 second with dies. Thus, the rates shown in FIG. 109 are dependent on this factor, but in other embodiments, more than one or less than one geometric substrate pattern may be filled with dies per second. Thus, for example, for first geometric substrate pattern 10802,192 dies may be transferred to corresponding substrates of a web in one second using a single pin plate having a pin array arranged as shown for pin array pattern 10804. This translates 11,520 dies transferred to substrates per minute, and to 691,200 dies transferred to substrates per hour. Thus, nearly 700,000 tags or other electronic devices can be assembled per hour using the current embodiment of the present invention. Other corresponding rates are shown for the remaining geometric substrate patterns in FIG. 109. In FIG. 109, example substrate areas are shown for illustrative purposes for each geometric substrate pattern, but it would be apparent to persons skilled in the relevant arts that each pattern can be applied to webs having substrates of different dimensions than shown.

[0305] FIG. 110 shows an enlarged view of geometric substrate pattern 10802, superimposed inside an example wafer outline 11080. Further, as shown in FIG. 110, substrates 116 of geometric substrate pattern 10902 are shaped in a hexagon shape indicated as hexagon outline 11002. By using a geometric pattern, such as geometric substrate pattern 10802, in the shape of a hexagon, advantages are realized during die transfer to large webs. For example, FIG.

111 shows various configurations for transferring dies to webs using geometric substrate pattern 10802. As shown in FIGS. 111A and 111B, geometric substrate pattern 10802 may be interlocked with others of geometric substrate pattern 10802 to entirely cover all substrates in a web in a coverage pattern. In other words, dies can be transferred from wafers or die plates in a pattern of geometric substrate pattern 10802 to a web and all substrates on the web receive dies.

[0306] For example, FIG. 111 a shows a web having a 20"width and a much greater length to which dies are being transferred. Web 11102 of FIG. 11 la can be a continuous web that is being rolled from a substrate web roll, or can be a discrete sheet. Furthermore, as shown in FIG. 111A, first and second die carousel heads 6064a and 6064b are positioned adjacent to web 11102. First die carousel head 6604a has three die transfer heads 6602a-6602c mounted thereon, and second die carousel head 6604b has three die transfer heads 6602d-6602f mounted thereon. Positioned as shown in FIG. 111 a, die transfer heads 6602a-6602f can cover all substrates of web 11102. For example, dies can be transferred from die transfer heads 6602a-6602f in their current locations. Then, web 11102 can be incremented or moved along its length until each of die transfer heads 6602a-6602f are positioned over the next corresponding arrays of substrates shaped as geometric substrate pattern 10802. Then, dies can be transferred from die transfer heads 6602a-6602f, filling this next set of substrates 116 with dies 104. This process can be continued until either die transfer heads 6602a-6602f are substantially depleted of dies, or until all substrates of web 11102 are filled with dies. If die transfer heads 6602a-f are depleted of dies, a second pair of carousel heads 6604a and 6604b can be moved over web 11102 to replace the previous die carousel heads, providing a new set of dies for transfer to web 11102. As shown in FIG. 111 a, substrates of geometric substrate pattern 10802 are completely interlocking such that no substrates are left uncovered by a die transfer head 6602. Thus, the interlocking geometric substrate pattern of pattern 10802 can be used to transfer dies to all substrates of a web.

[0307] FIG. lllb shows a similar system as is shown in FIG. 111a, except that a web 11104 is narrower than web 11102 of FIG. alla. Thus, as shown in FIG. I l lb, only five die transfer heads 6602a-6602e are required to provide coverage of web 11104.

[0308] FIG. lllc shows a system similar to that shown in FIG. lllb except that a web 11106 shown is narrower than web 11104 shown in FIG. lllb.

Thus, as shown in FIG. lllc, even fewer die transfer heads 6602a-d are required to provide complete, interlocking covering of all substrates of web 11106.

[0309] Thus, in a similar fashion, each of the other geometric substrate patterns shown in FIGS. 108a and 108b can be used to provide complete, interlocking coverage of all substrates in a web. Example application of the remaining geometric substrate patterns shown in FIGs. 108a and 108b are described below.

[0310j FIG. 112 shows geometric substrate pattern 10806 superimposed within an example wafer outline 11010. As shown in FIG. 112, geometric substrate pattern 10806 includes a plurality of substrates 116 formed in a shape substantially approximating a hexagon. Because of the shape of geometric substrate pattern 10806, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10806, completely covering each substrate 116 in the web.

For example, FIG. 113A shows an example web 11302 having a width of 24 inches. Die transfer to all substrates 116 of web 11302 is completely covered by six die transfer heads 6602 positioned as shown in FIG. 113A, or positioned in a similar fashion. Die transfer heads 6602 transfer dies according to the shape of geometric substrate pattern 10806. For example, each die transfer head 6602 can include a pin plate 10808 having a layout of pins 4704 shaped like geometric substrate pattern 10806 to transfer the dies.

In another example, FIG. 113B shows an example web 11304 having a 12 inch width that is covered in a similar fashion by four die transfer heads 6602 positioned as shown.

[0311] FIG. 114 shows geometric substrate pattern 10810 superimposed within an example wafer outline 11010. As shown in FIG. 114, geometric substrate pattern 10810 includes a plurality of substrates 116 formed in a shape substantially approximating a hexagon. Because of the shape of geometric substrate pattern 10810, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10810, completely covering each substrate 116 in the web.

For example, FIG. 115A shows an example web 11502 having a width of 14 inches. Die transfer to all substrates 116 of web 11502 is completely covered by six die transfer heads 6602 positioned as shown in FIG. 115A, or positioned in a similar fashion. Die transfer heads 6602 transfer dies according to the shape of geometric substrate pattern 10810. For example, each die transfer head 6602 can include a pin plate 10812 having a layout of pins 4704 shaped like geometric substrate pattern 10810 to transfer the dies.

In another example, FIG. 115B shows an example web 11504 having a 28 inch width that is covered in a similar fashion by twelve die transfer heads 6602 positioned as shown.

[0312] FIG. 116 shows geometric substrate pattern 10818 superimposed within an example wafer outline 11010. As shown in FIG. 116, geometric substrate pattern 10818 includes a plurality of substrates 116 formed in a shape substantially approximating a hexagon, cross, or diamond shape.

Because of the shape of geometric substrate pattern 10818, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10818, completely covering each substrate 116 in the web. For example, FIG. 117A shows an example web 11702 having a width of 30 inches. Die transfer to all substrates 116 of web 11702 is completely covered by twelve die transfer heads 6602 positioned as shown in FIG. 117A, or positioned in a similar fashion. Die transfer heads 6602 transfer dies according to the shape of geometric substrate pattern 10818.

For example, each die transfer head 6602 can include a pin plate 10820 having a layout of pins 4704 shaped like geometric substrate pattern 10818 to transfer the dies. In another example, FIG. 117B shows an example web 11704 having a 15 inch width that is covered in a similar fashion by six die transfer heads 6602 positioned as shown.

[03131 FIG. 118 shows geometric substrate pattern 10814 superimposed within an example wafer outline 11010. As shown in FIG. 118, geometric substrate pattern 10814 includes a plurality of substrates 116 formed in a shape substantially approximating a square or rectangular shape. Because of the shape of geometric substrate pattern 10814, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10814, completely covering each substrate 116 in the web. For example, FIG. 119A shows an example web 11902 having a width of 30 inches. Die transfer to all substrates 116 of web 11902 is completely covered by twelve die transfer heads 6602 positioned as shown in FIG. 119A, or positioned in a similar fashion. Die transfer heads 6602 transfer dies according to the shape of geometric substrate pattern 10814. For example, each die transfer head 6602 can include a pin plate 10816 having a layout of pins 4704 shaped like geometric substrate pattern 10814 to transfer the dies. In another example, FIG. 119B shows an example web 11904 having a 15 inch width that is covered in a similar fashion by six die transfer heads 6602 positioned as shown.

[03141 FIG. 120 shows geometric substrate pattern 10822 superimposed within an example wafer outline 11010. As shown in FIG. 120, geometric substrate pattern 10822 includes a plurality of substrates 116 formed in a shape substantially approximating a square or rectangular shape. Because of the shape of geometric substrate pattern 10822, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10822, completely covering each substrate 116 in the web. For example, FIG. 121A shows an example web 12102 having a width of 30 inches. Die transfer to all substrates 116 of web 12102 is completely covered by twelve die transfer heads 6602 positioned as shown in FIG. 121A, or positioned in a similar fashion. Die transfer heads 6602 transfer dies according to the shape of geometric substrate pattern 10822. For example, each die transfer head 6602 can include a pin plate 10824 having a layout of pins 4704 shaped like geometric substrate pattern 10822 to transfer the dies. In another example, FIG. 121B shows an example web 12104 having a 17 inch width that is covered in a similar fashion by six die transfer heads 6602 positioned as shown.

[0315] FIG. 122 shows geometric substrate pattern 10826 superimposed within an example wafer outline 11010. As shown in FIG. 122, geometric substrate pattern 10826 includes a plurality of substrates 116 formed in a shape substantially approximating a rectangular shape. Because of the shape of geometric substrate pattern 10826, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10826, completely covering each substrate 116 in the web, as described above for other geometric substrate patterns.

[0316] FIG. 123 shows geometric substrate pattern 10830 superimposed within an example wafer outline 11010. As shown in FIG. 123, geometric substrate pattern 10830 includes a single substrate 116 formed in a shape substantially approximating a square or rectangular shape. Because of the shape of geometric substrate pattern 10830, pluralities of dies 104 can be transferred to substrates 116 on a web in a repeating, interlocking pattern of geometric substrate patterns 10830, completely covering each substrate 116 in the web, as described above for other geometric substrate patterns.

[0317] FIG. 124 shows example steps related to a flowchart 12400 for designing a system for assembling RFID tags for a tag population, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant art (s) based on the following discussion. For example, it will be apparent to persons skilled in the relevant art (s) that the process of flowchart 12400 could be applied to assembly of any type of electronic device, in addition to RFID tag devices. Note that in alternative embodiments, the steps shown in FIG. 124 can occur in an order other than that shown, and in some embodiments, not all steps shown are necessary.

[0318] Flowchart 12400 begins with step 12402. In step 12402, a required minimum read distance for tags of the tag population is determined. For example, when tags are desired for applications, it is typically known or determinable what distance the tags and readers will be required to communicate.

[0319] In step 12404, a tag antenna layout and corresponding tag substrate size is selected based upon the determined required read distance. For example, after the minimum read distance is determined in step 12402, a corresponding antenna layout and substrate size can be determined. Any sizes for antennas and substrates are applicable to the present invention, including the layouts and sizes described elsewhere herein, or those otherwise known.

[0320] In step 12406, a number of tags to be produced for the tag population is determined. For example, a known number of tags may be required for a particular application. Thus, this number of tags may be desired to be produced. Alternatively, a number of tags to be produced may be based upon a general tag production run size, and/or other parameter.

[0321] In step 12408, a tag substrate web, comprising a plurality of tag substrates, is configured based upon the selected tag substrate size and the determined number of tags to be produced. For example, the width and length dimensions of the tag substrate web can be determined. For example, the width may be determined by selecting a web width from a set of available web widths, such as those mentioned elsewhere herein, or otherwise known. The length of the web may determined by dividing the determined number of tags to be produced by the width of the web in substrates. Note that the web may be a continuous substrate web, having a relatively large length, and may be stored on a roll. Alternatively, the web may be formed from a plurality of separate web sheets, that are substantially rectangular or square shaped.

[0322] In step 12410, a number of die transfer heads that are each capable of transferring a plurality of dies to corresponding substrates of the tag substrate web is determined. For example, a number of die transfer heads may be selected to cover a width of the web, such as described above with respect to FIGS. 66-107 and 110-123. In embodiments, as described above with respect to FIGS. 108A-123, a geometrical substrate pattern capable of self- interlocking may be selected for transfer of dies from each die transfer head.

As described above, the interlocking geometrical substrate pattern may be selected to be a square, a rectangle, a hexagon, or a cross, for example.

[0323] As described above, each die transfer head can be designed to include a die plate, such as die receptacle structure 1300 or die plate 3600. Thus, step 12410 can include the step where a die plate die plate is selected having predetermined die holding capacity. Furthermore, as described above, each die transfer head can be designed to include a pin plate, such as pin plate 4700, for transferring dies. Thus, step 12410 can include the step where a pin pitch is selected for pins of the pin plate based upon the selected tag substrate size.

[0324] In step 12412, a location for each of the determined number of die transfer heads relative to the tag substrate web is designated. For example, the die transfer heads can be arranged in an interlocked coverage pattern, as described above, and shown, for example, in FIGS. 67 and 111A-B. In an embodiment, the self-interlocking geometrical substrate pattern can be selected to minimize a number of dies that cannot be transferred from each die transfer head due to the selected self-interlocking geometrical substrate pattern, while covering each substrate of the tag substrate web with a die transfer head of the coverage pattern in a non-overlapping manner. The die transfer heads can be arranged in a coverage pattern such that when as the tag substrate web is incremented or moved along, all substrates of the tag substrate web can be covered by at least one die transfer head of the coverage pattern. In some embodiments, the die transfer heads are arranged in a coverage pattern such each substrate of the tag substrate web can be covered only by a single die transfer head of the coverage pattern-i. e. , the coverage pattern is interlocking and non-overlapping.

[0325] In step 12414, a rate of tag production is determined. For example, a rate of tag production can be determined based upon any of a number of factors, including the determined required number of tags and a designated completion date. The rate of tag production may be limited by the particular assembly equipment in use. However, the present invention allows for much greater production rates than previously was possible.

2.1. 3.3 Die Transfer Using a Punch Cylinder [0326] In alternative embodiments, a cylinder having a plurality of punching members extending radially therefrom can be rolled across a die plate to transfer dies therefrom. FIG. 155 depicts a punch cylinder 15500, according to embodiments of the present invention. Punch cylinder 15500 includes a cylinder 15510 having an outer surface. Cylinder 15510 has a plurality of punching members 15504 extending radially therefrom.

[0327] In an embodiment, the cylinder is rolled across the die plate to transfer a first plurality of dies from the die plate to a first plurality of substrates of the web of substrates. As the cylinder is rolled a first set of punching members temporarily extends. through one or more holes of the die plate. As the first set of punching members is being withdrawn from holes in the die plate, a second set of punching members extends through one or more holds of the die plate.

This process continues as the cylinder is rolled across the die plate.

[0328] In another embodiment, the cylinder is rolled across the die plate in a first direction to transfer a first plurality of dies from the die plate to a first plurality of substrates of the web of substrates. The cylinder is then rolled across the die plate in a second direction, opposite the first direction, to transfer a second plurality of dies from the die plate to a second plurality of substrates. After the cylinder is rolled in the first direction, the web of substrates may be moved to position the second plurality of substrates under the second plurality of dies.

2.1. 3.4 Die Transfer from Intermediate Surface to Substrate Using Expandable Material [0329] FIG. 125 shows a flowchart 12500 of a method for transferring dies from an intermediate surface to a substrate using a changeable or movable material, according to embodiments of the present invention. The flowchart depicted in FIG. 125 is described with continued reference to FIGs. 126-129.

However, flowchart 12500 is not limited to those embodiments. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion. Note that in alternative embodiments, steps shown in FIG. 125 can occur in an order other than that shown, and in some embodiments, not all steps shown are necessary.

[0330] Flowchart 12500 begins at step 12502 when a die plate is received that has a first surface having a plurality of dies attached thereto. The die plate has a plurality of holes extending from the first surface to a second surface. Each attached die covers a corresponding hole at the first surface of the die plate.

[0331] FIG. 126 shows a die plate 12600 having a plurality of dies 104 attached to a first surface of the die plate. As shown in FIG. 126, each die 104 covers a corresponding hole 12606 through die plate 12600 at the first surface of die plate 12600.

[0332] In step 12504, each hole of the die plate is at least partially filled with a material. For example, the hole may be filled with a material that can be caused to expand, a material that can be caused to exert pressure in multiple directions, or a material that moves when exposed to a certain stimulus or stimuli.' [0333] For example, as shown in FIG. 127, each hole 12606 is at least partially filled with a material. For example, as shown in FIG. 127, hole 12606a is filled with a material 12702. Material 12702 can be any material that can be caused to expand or contract when exposed to stimuli, including an epoxy, a plastic, a polymer, a glass, or other material or combination thereof.

Alternatively, the material can be any material that can be caused to exert pressure in multiple directions or change positions when exposed to stimuli including a magnetic fluid, artificial muscle material, or other material or combination thereof.

[0334] In step 12506, the die plate and one or more substrates are positioned to be closely adjacent to each other such that contact pads of each die of the plurality of dies are closely adjacent to corresponding contact areas on the first surface of the substrate.

[0335] For example, FIG. 128 shows a die plate 12600 and substrate 116 are positioned to be closely adjacent to each other such that contact pads 204a and 204b of die 104 are closely adjacent to corresponding contact areas 210 on a first surface of substrate 116. Note that die plate 12600 and substrate 116 in various embodiments can be positioned to varying degrees of closeness to each other, including distances other than that shown in FIG. 128.

[0336] In step 12508, a stimulus (or stimuli) is applied to the material to cause the material in each hole to release a corresponding die from the die plate. For example, the material is caused to expand, exert pressure, or move in the hole.

This action by the material releases each die of the plurality of dies from the die plate. Example stimulus that can be used are heating, application of a voltage, application of a force, or application of other stimulus or combination thereof. The stimulus used is determined based on the physics and/or characteristics of the material used to fill the holes of the die plate.

[0337] For example, FIG. 129 shows a exemplary material 12702 that is caused to expand in hole 12606a. By expanding, material 12702 detaches die 104a from the bottom surface of die plate 12600. Thus, die 104a is moved by material 12702 to contact with substrate 116a.

[0338] Note that in the example of FIG. 128, a laser 12802 is depicted that causes the material 12702 filling each hole to expand. Laser 12802 directs a beam towards material 12702, which heats material 12702 to cause it to expand. Note that in alternative embodiments, other methods may be used to cause material 12702 to expand. In this manner, an expandable material can be used to transfer dies from a die plate, in place of the use of punch pins of a pin plate.

[0339] Furthermore, FIG. 129 also shows an adhesive material 12812a adhering contact pads 204 of die 104 to the corresponding contact areas 210 on the first surface of substrate 116a. Thus, in an embodiment, the adhesive material 12812a is cured or otherwise treated to cause die 104a to adhere to substrate 116a.

2.1. 4 Direct Die Transfer [0340] FIG. 130 shows example steps related to a flowchart 13000 for transferring dies directly from a support structure to a substrate, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion.

[0341] FIGs. 131 to 135 relate to the steps of flowchart 13000. FIG. 131 shows plurality of dies 104 attached to a support surface or support structure 404. FIG. 131 further shows a single substrate 116a of a web 808.

[0342] FIG. 132 shows an example of a web 808.

[0343] FIG. 132 shows an example of step 13002 of flowchart 13000. As shown in FIG. 132, support structure 404 and substrate 116a are positioned closely adjacent to each other such that contact pads 204 of die 104a make contact with corresponding contact areas 210 of substrate 116 of web 808.

[0344] According to step 13004 of flowchart 13000, an adhesive material 5202a is allowed to adhere the contact pads 204 of die 104a to the corresponding contact areas 210 on the first surface of substrate 116a.

[0345] FIG. 133 shows an example of step 13006 of flowchart 1300. As shown in FIG. 133, a light pipe 13302 is applied to support structure 404 on a surface of support structure 404 opposite that to which die 104a is attached.

Light pipe 13302 can be any type of optical structure, such as an optical tube, optical fiber, including a communications optical fiber, that allows light to pass through. For example, FIG. 133 shows a light 13304 being emitted from light pipe 13302. In an embodiment light 13304 is ultraviolet light. Light 13304, however, can comprise other wavelengths of light. In the current embodiment, die 104a is attached to support structure 404 by an adhesive material that can be caused to release die 104 when a light of a particular wavelength, such as ultraviolet light is applied thereto. Thus, as shown in FIG. 135, die 104a can be released from support structure 404, whereby die 104a remains attached to substrate 116a of web 808, by the application of light 13304 from light pipe 13302.

[0346] Alternatively, or additionally, light pipe 13302 may come in contact with support structure 404, as shown in FIG. 134. Thus, as shown in FIG.

134, an end of light pipe 13302 can be used to push through support structure 404 to cause die 104a to come into contact with the contact areas of substrate 116a. During this process, as described above, light 13304 causes die 104a to be released from support structure 404, and to remain attached to substrate 116a, as shown in FIG. 135.

[0347] In an embodiment, dies are attached to a support structure by an adhesive material that can be caused to release the dies when heat is applied thereto. In this embodiment, in step 13006, heat is applied to a second surface of the support structure, opposite the die, to cause the die to release from the first surface of the support structure.

[0348] In an embodiment, in step 13006, the support structure is moved apart from the substrate so that the dies remain attached to the substrate due to the adhesive material overcoming the adhesiveness of the support structure. For example, the adhesiveness of the adhesive material between the substrate and die is stronger than the adhesiveness of the adhesive material between the dies and the support structure.

[0349] In an embodiment, in step 13006, the support structure is peeled from the substrate.

[0350] In the embodiments described above, an adhesive material may be applied to the contact areas of the substrate and/or to a second surface of the dies, opposite the support structure.

3.0 Device Assembly [0351] FIG. 156 shows an example of a device assembly system 15600, according to an example embodiment of the present invention. Device assembly system 15600 receives a substrate web and one or more die plates, each die plate having dies aligned thereon. In an embodiment, the received wafer is previously scribed. Alternatively, system 900 may include a wafer scriber.

[0352] Device assembly system 15600 includes an optional adhesive application module 15620 and a die transfer module 15640. Optional adhesive application module 15620 is configured to deposit adhesive on each substrate 116 of substrate web 15604. In an embodiment, assembly system 15600 does not include an adhesive application module and instead receives a substrate web having adhesive (e. g. , adhesive screen printed on substrate web) applied.

[0353] In an embodiment, an adhesive inspection module 15630 is included after adhesive application module 15620. Adhesive inspection module 15630 inspects the deposition of adhesive to determine if it complies with defined criteria.

[0354] Die transfer module 15640 receives a die plate 15602 having dies and a substrate web 15606 having adhesive applied. Die transfer module 15640 is configured to transfer die from a die plate 15602 (also referred to as a"wafer plate") to substrate web 15606. In an embodiment, an inspection module 15660 is included after the die transfer module 15640. Inspection module 15660 inspects the resulting assembled devices to determine if they comply with predefined criteria.

3.1 Adhesive Application Module [0355] Adhesive application module 15620 includes an adhesive reservoir 15622, adhesive pin plate 15624, and a pin plate controller 15626. In an embodiment of the invention, adhesive application module 15620 is a"dip and wick"application system. As would be appreciated by persons of skill in the art, other types of adhesive application systems can be used to apply adhesive onto the substrate.

[0356] Adhesive application module 15620 applies adhesive to an area of a substrate 116 of substrate web 15604. In an embodiment, the adhesive is applied to a die contact area proximate to an antenna printed or embossed on each substrate 116. Adhesive application module 15620 is configured to apply adhesive to a plurality of substrates of substrate web 15604 in parallel.

[0357] Adhesive reservoir 15622 holds an adhesive. In an embodiment, adhesive reservoir 15622 holds the adhesive under the appropriate conditions for optimal application on the substrate (e. g. , temperature). In an embodiment, the adhesive is a light curable adhesive. Alternatively, the adhesive can be a glue, epoxy, laminate, or any other adhesive material otherwise known or described elsewhere herein.

[0358] Adhesive pin plate 15624 comprises a body having a first and second surface and a plurality of pins extending from the first surface. Details of an example adhesive pin plate 15624 are described below in section 2.1. 3. In an embodiment, the pins of adhesive pin plate 15624 have a larger diameter than pins of a die transfer pin plate 15644, although they can alternatively be the same diameter or smaller. In an embodiment, the configuration of pins used for adhesive pin plate 15624 is identical to the configuration of pins used for die transfer pin plate 15644. Alternatively, the configurations of pins used for adhesive pin plate 15624 and die transfer pin plate 15644 are different.

[0359] Adhesive pin plate controller 15626 is configured to move adhesive pin plate 15624 during the adhesive application process. In an exemplary dip and wick adhesive application module, adhesive pin plate controller 15626 is configured to dip the pins of adhesive pin plate 15624 into adhesive reservoir 15622. Adhesive pin plate controller 15626 is further configured to move adhesive pin plate 15624 to a position adjacent to substrate web 15604 such that the pins of adhesive pin plate 15624 are above, but not touching, substrate web 15604. When located at the appropriate position, adhesive on the pins of adhesive pin plate 15624 is transferred (e. g. , wicked) from the pin onto substrates 116 of substrate web 15604. Alternatively, the pins of plate 926 can contact the substrate. Typically, the adhesive is transferred onto each substrate 116 of the web 904 at one or more die mount locations.

3.2 Die Transfer Module [0360] Die transfer module 15640 includes a pin plate controller 15642, pin plate 15644, and a die plate controller 15646. In an embodiment, die transfer module 15640 also includes a curing module 15650. Die transfer module 15640 receives a die plate having dies 15602 and a substrate web having adhesive 15606.

[0361] A die plate is used for transferring dies from wafers or support surfaces to substrates or subsequent transfer surfaces. A die plate having die cavities or cells, where each cell has a corresponding opening or hole, can be used. In this type of die plate, each cavity or cell can hold a die. This type of die plate is also referred to as a"die receptacle structure, ""waffle structure,""waffle grid, ""nest structure,"or"nest grid."A die plate having a substantially planar body and a plurality of holes can also be used. In this type of die plate, a die can be attached to the surface of the die plate and positioned over a corresponding hole. As would be appreciated by persons of skill in the art, other types of die plates can be used with the invention. For ease of description, the term"die plate"is used herein to encompass all types of die plates.

[0362] Die transfer pin plate 15644 is configured to transfer a plurality of dies from die plate 15602 to the die contact area on a plurality of substrates 116 of \ substrate web 15606. Pin plate 15644 is described in further detail in section 2. 1. 3.

[0363] Die transfer pin plate controller 15642 is configured to move die transfer pin plate 15644 in order to transfer die from die plate 15602 to substrates 116 of substrate web 15606. In an embodiment, pin plate controller 15642 moves pin plate 15644 in a reciprocal manner. Details of the transfer of die from a die plate to substrates using a pin plate are described in section 2.2.

[0364] Die plate controller 15646 is configured to move die plate 15602 relative to pin plate 15644 and substrate web 15606. For example, in an embodiment, application of pin plate 15644 to die plate 15602 does not result in the transfer of all dies located on die plate 15602 to substrates 116. In this example, after pin plate 15644 causes a first group of dies to be transferred, die plate controller 15646 moves die plate 15602 to position a second group of dies on die plate 15602 for transfer by pin plate 15644. This process is repeated until the maximum possible number of die is transferred from die plate 15602 to substrates 116.

[0365] In an embodiment, die transfer module 15640 includes a curing module 15650. Curing module 15650 is configured to cure the adhesive on substrate 116 in order to bond die 104 to substrate 116. In an embodiment, the curing module 15650 is a ultraviolet (UV) light source. Example curing module 15650 embodiments are described below.

3.3 Method for Device Assembly [0366] FIG. 157 shows a flowchart 15700 of a method for assembling devices, according to embodiments of the present invention. The flowchart depicted in FIG. 157 is described with continued reference to FIG. 156. However, flowchart 15700 is not limited to that embodiment.

[0367] The method for device assembly begins at step 15710 when system 15600 receives a die plate 15602 having dies aligned thereon. In an embodiment, die plate 15602 is loaded from a wafer/die plate loader capable of storing a plurality of wafer/die plates 15602. In an alternate embodiment, system 15600 receives multiple wafer/die plates in parallel. This embodiment is described in further detail in section 2.2. 4.

[0368] In step 15720, a web of substrates is received. In an embodiment, the web of substrates is received on a continuous roll. In an alternate embodiment, the web of substrates is received on separate sheets of material.

In an exemplary embodiment of RFID tag assembly, each substrate in the web of substrates includes an antenna.

[0369] Step 15730 is optional. When present, in step 15730, an adhesive is applied to the die contact areas of a plurality of substrates. Optional step 15730 is described in more detail in reference to FIG. 27.

[0370] When step 15730 is not present, the web of substrates received in step 15720 has adhesive applied to the die contact areas. In this embodiment, the adhesive may be applied by a screen printing process, prior to receipt by system 15600. As would be appreciated by persons of skill in the art, other methods for applying adhesive prior to device assembly could be used.

[0371] In step 15740, a plurality of dies are transferred from one or more die plate (s) 15602 to the corresponding die contact areas of a plurality of substrates.

[0372] Step 15750 is optional. When present, in step 15750, the assembled devices are inspected to determine if each assembled device complies with redefined criteria.

[0373] FIG. 158 further describes step 1830 of FIG. 157. FIG. 158 shows a flowchart 15800 of a method for applying adhesive to a substrate, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion.

[0374] Flowchart 15800 begins in step 15810 when a substrate web is received.

[0375] In step 15820, adhesive pin plate 15624 is positioned adjacent to adhesive reservoir 15622.

[0376] In step 15830, adhesive pin plate 15624 is moved such that adhesive is applied to each pin of the adhesive pin plate. For example, in step 15830, adhesive pin plate 15624 is dipped into the adhesive stored in adhesive reservoir 15622. Adhesive then adheres to the tip of each pin.

[0377] In step 15840, adhesive pin plate is positioned adjacent to the web of substrates such that each pin of the adhesive pin plate is positioned adjacent to a die contact area of a substrate on the web of substrates.

[0378] In step 15850, adhesive is applied to a plurality of die contact areas of substrates of the web of substrates in parallel. In an embodiment, in step 15850, adhesive pin plate is moved to a position so that the tips of each pin are located at a redefined distance above the substrate. The adhesive then wicks from the tip of the pin to the substrate. In this embodiment, the pins do not contact the substrate directly.

[0379] In step 15860, adhesive pin plate 15860 is withdrawn from the position adjacent to the web of substrates.

[0380] Subsequently, the substrate web is incremented and the steps of flowchart 15800 are repeated.

4.0 Pin Plate with Removable Pins [0381] FIG. 159A shows a portion of an exemplary pin plate 15900 having removable pins, according to example embodiments of the present invention.

Pin plate 15900 includes a pin holding portion 15920 and a backing portion 15930. In an embodiment, pin holding portion 15920 and backing portion 15930 are plates having identical dimensions in the x and y directions.

Alternatively, pin holding portion 15920 and backing portion 15930 have different dimensions in the x and/or y directions. The pin holding portion 15920 and backing portion may have different thicknesses (dimension in the z direction).

[0382] Pin holding portion 15920 is configured to hold one or more pins 15904. Pin holding portion 15920 has one or more cavities 15922. Cavity 15922 is open at the first surface 15926 of pin holding portion 15920 and extends partially through pin holding portion 15920 in the z direction (i. e., downward in FIG. 159a). The geometry and dimensions of cavity 15922 are designed relative to the geometry and dimensions of the pin to be inserted into the cavity. For example, if the pin has a cylindrical shape, cavity 15922 also has a cylindrical geometry.

[0383] A hole 15924 extends from the bottom of cavity 15922 to the second surface 15928 of pin holding portion 15920. Hole 15924 is open at the second surface 15928 of pin holding portion 15920. The pin portion 15908 of pin 15904 extends through hole 15924 when pin 15904 is inserted into the cavity, as depicted FIG. 159a. The geometry and dimensions of hole 15924 are designed relative to the geometry and dimensions of pin portion 15908 of pin 15904. In an embodiment, the size of hole 15924 is smaller than the size of cavity 15922.

[0384] Pin 15904 includes an anchor portion 15906 and a pin portion 15908.

In an embodiment, anchor portion 15906 is wider than pin portion 15908.

This allows pin 15904 to be held in pin holding portion 15920. The length of pin portion 15908 is designed to allow the pin portion 15904 to extend through hole 15924 and through a corresponding hole in a die plate. FIG. 159B depicts two exemplary pins 15904a and 15904b. In pin 15904a, anchor portion 15906a has a cylindrical shape. In pin 15904b, anchor portion 15906b has a rectangular (cuboid) shape. In an embodiment, pin portion 15908 has the same geometrical shape as anchor portion 15906. Alternatively, pin portion 15908 may have geometrical shape different than anchor portion 15906. For example, in pin 15904b, pin portion 15908 may have a cylindrical shape. As would be appreciated by persons of skill in the art, other geometrical shapes can be used for anchor portion 15906 and pin portion 15908.

[0385] Pin 15904 is configured to be placed in cavity 15922. In an embodiment, pin 15904 is placed in a sleeve (not shown) in cavity 15922. The sleeve has a geometry similar to the geometry of anchor portion 15906 of pin 15904 and is physically separate from the pin holding portion 15922.

[0386] In an embodiment, pin plate 15900 also includes one or more springs 15910, one per pin 15904. In the exemplary pin plate 15900 depicted in FIG.

159A, spring 15910 is included in cavity 15922 between the anchor portion of pin 15904 and backing portion 15930. As would be appreciated by persons of skill in the art, spring 15910 can be included at different points of the cavity.

Springs 15910 allow for impact absorption. For example, when a pin 15904 is used to push a die onto a substrate, spring 15910 absorbs some of the impact, so that pin 1604 does not crush the die against the substrate.

5.0 Recovery of Untransferred Dies from a Wafer [0387] The die receptacle structure described herein can be used to recover dies from a wafer that are not otherwise transferred to a subsequent surface.

For example, FIG. 160 shows a flowchart 16000 of a method for recovering untransferred dies using a die receptacle structure, according to embodiments of the present invention. However, flowchart 16000 is not limited to those embodiments. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant arts based on the following discussion. Note that in alternative embodiments, the steps shown in FIG. 160 can occur in an order other than that shown.

[0388] Flowchart 16000 begins at step 16010 when a wafer and, optionally, a first die plate are received. The first die plate can be a die receptacle structure, as described above, or a die plate without die receptacles, as described elsewhere herein.

[0389] In step 16020, dies are transferred from the wafer to the die plate (or a substrate). For example, the dies can be transferred as described elsewhere herein.

[0390] In step 16030, a determination is made whether any die remain on the wafer following transfer step 16020. If a determination is made that no dies remain on the wafer, operation proceeds to step 16040. If a determination is made that dies remain on the wafer (and can be recovered), operation proceeds to step 16050.

[0391] FIG. 161 shows an exemplary wafer 16100 having a plurality of dies remaining after a transfer step is completed. As shown in FIG. 161, dies have been removed from the center of the wafer. However, dies remain in the periphery of the wafer. For example, as shown in FIG. 161, dies remain at positions of wafer 161000 labeled 1-10,17, 24,25, 32, and 39-48. The configuration of dies remaining on the wafer after the transfer step is dependent upon the shape of the die plate to which the dies are transferred and/or upon the method used for transfer. For example, one or more rows or columns of dies may also remain after the transfer.

[0392] In step 16040, the recovery process for the wafer ends.

[0393] In step 16050, a die receptacle structure is received. For example, the die receptacle structure may be die receptacle structure 1300 shown in FIG.

13A, having as many cells (rows/columns) as desired.

[0394] In step 16060, the dies remaining on the wafer are transferred to cells 904 in the die receptacle structure 900. This transfer can be via any means including a pin plate, such as described elsewhere herein, or via a chip sorter or other similar pick and place technology. If a pin plate is used for the transfer, the pin plate may be designed with a pin configuration to maximize the transfer of the remaining dies. For example, the die recovery pin plate may have a different pin configuration (e. g. , pins on the periphery but no pins in the central portion) than the die transfer pin plate. For example, because the configuration of remaining dies on a wafer is known and consistent, a pin plate can be designed to have a substantially similar configuration to the configuration of remaining dies.

[0395] Note that all cells in the die receptacle structure may or may not be filled with a die after completion of the recovery process. The resulting die receptacle structure can then be used as a die plate in the device assembly process.

[0396] The system and method for recovering untransferred dies described above may be incorporated into the device assembly system described above in reference to FIG. 156.

6.0 Example Tag Applications [0397] All types of objects may have RFID tags applied thereto for all types of purposes, including of tracking, inventory, security checks, etc. According to embodiments of the present invention, the tags may be applied to the objects after the objects are manufactured. In further embodiments of the present invention, the tags may be incorporated in the objects during manufacture of the objects. Tags may be incorporated into any number of types of objects. Example objects in which a tag may be incorporated during manufacturing, and example manufacturing processes therefor, are described below.

[0398] In an embodiment of the present invention, a compact disc/optical disc medium that is tagged, and its manufacture, is described. In other words, manufacturing techniques for optical discs or compact discs that incorporate RFID tag technology are described. In this manner, the optical disc or compact disc medium of the present invention is trackable. The present invention is applicable to any type of optical disc or compact disc, including compact disc read only memories (CDROM), CD-RW (CD re-writable), digital video discs (DVD), DVD-R, DVD-RW, and other types of compact discs or optical discs.

[0399] For example, FIG. 136 shows an example tagged or trackable optical disc 13600, according to an embodiment of the present invention. Optical disc 13600 includes a disc substrate 13610, a metal layer 13602, a die 104, and an electrical connection 13606. Metal layer 13602 is formed on disc substrate 13610. Metal layer 13602 is digitally encoded with the information stored by optical disc 13600. Disc substrate 13610 is typically a plastic disc, but can be made from other materials. A die 104 is mounted on disc substrate 13610.

Furthermore, optical disc 13600 has a centrally located opening. According to embodiments of the present invention, die 104 is coupled to metal layer 13602 by electrical connection 13606. Metal layer 13602 operates as an antenna for optical disc 13600. Die 104 includes logic/processing capability for receiving signals from RFID readers, and transmitting responses to the same, through the antenna of metal layer 13602. Thus, optical disc 13600 operates as a RFID tagged object. In embodiments, electrical connection 13606 includes an impedance matching network to match die 104 with the antenna of metal layer 13602.

[0400] FIG. 137 shows example steps related to a flowchart 13700 for manufacturing a tagged optical disc, such as optical disc 13600, according to embodiments of the present invention. Further operational and structural embodiments of the present invention will be apparent to persons skilled in the relevant art based on the following discussion. Furthermore, FIGs. 138 to 141 relate to the steps of flowchart 13700.

[0401] FIG. 138 shows an example of step 13702 of flowchart of 13700. For example as shown in FIG. 138, a metal layer, such as metal layer 13602, is deposited on the disc substrate 13610 of optical disc 13600. For example, metal layer 13602 can be deposited on optical disc 13800 using a disc vapor metalization process, where a metal vapor 13804 is applied to optical disc 13800.

[0402] Furthermore, in step 13702, at least one pair of metal traces on the disc are formed that are connected to metal layer 13602. In an embodiment, the metal traces of the one or more pairs are positioned on opposite sides of the central opening 13608. For example, as shown in FIG. 138, these metal traces are formed using a modified disc hub 13802. Disc hub 13802 is shown centrally located on optical disc 13600 in FIG. 138. Disc hub 13802 can be a conventional disc hub, with feed lines formed therein, to allow the metal deposition process to form traces on the disc substrate 13610. Thus, through the use of disc hub 13802, conventional processes can be used to metallize an optical disc, while disc hub 13802 allows the addition of metal traces for connectivity to an integrated circuit die, as described below. Little or no interruption of normal disc metallization is caused by disc hub 13802.

[0403] FIGS. 139A-139C and 140A-140C show further details of example embodiments of modified disc hub 13802. As shown in FIG. 138, disc hub 13802 is present on optical disc 13600 when metal vapor 13804 is applied to optical disc 13600. As shown in FIGS. 139A-139C, disc hub 13802 has modifications made thereto, in the form of feed lines 13902. FIGS. 139A- 139C shows side, top and bottom views of disc hub 13802, respectively. As shown in FIGS. 139B and 139C, a first circumferential feed line 13902a is continuous around an outer area of disc hub 13802, near an outer edge of disc hub 13802. Four feed line segments 13902b-e are spaced around disc hub 13802, and are coupled to the first circumferential feed line 13902a. The four feed line segments 13902b-e extend radially outward to the edges of disc hub 13802. Thus, when a metal vapor is applied to optical disc 13600 that mounts disc hub 13802, traces are formed in feed lines 13902a-e on the top surface of optical disc 13600. Feed lines 13902 allows metal to migrate to the portions of the optical disc that are thereby exposed to create metal traces on the optical disc. These metal traces are used to couple die 104 to metal layer 13602, as further described below. For example, the metal traces allows a direct contact between metal layer 13602 and a matching network (coupled to die 104) on an interposer applied to the optical disc.

[0404] Note that in an embodiment, a collar ring 13904 may be present, when needed to hold together outer segments of disc hub 13802 that may be otherwise loosely coupled to disc hub 13802 due to feed lines 13902b-e, as shown in FIGS. 139B and 139C. As shown in FIGS. 139A-139C, collar ring 13904 wraps around an outer circumference of disc hub 13802.

[0405] Furthermore, disc hub 13802 includes a central bore 13912. Central bore 13912 may be present to be used to hold/handle disc hub 13802, and to align disc hub 13802 with a disc substrate 13610 (e. g. , align disc hub 13802 with a central hole through disc substrate 13610).

[0406] FIG. 139D shows an interposer 13920, according to an embodiment of the present invention. Interposer 13920 includes an interposer substrate 13930, matching network 13908, a die 104, and a conductive ring 13910 that is electrically coupled to die 104 and matching network 13908. Furthermore, interposer 13920 has a conductive adhesive 13906 formed at least around an outer edge of interposer 13920. Thus, as shown in step 13704 of FIG. 137, interposer 13920 can be applied to a disc substrate 13610 after metal layer 13602 has been formed thereon, to complete assembly of optical disc 13600.

For example, interposer 13920 may be applied to disc substrate 13610 in a sticker-like fashion, or in any other manner. Interposer 13920 may include further adhesive material (e. g. , non-conductive) to enhance adhesion of interposer 13920 to disc substrate 13610.

[0407] When interposer 13920 is attached to disc substrate 13610, conductive ring 13910 of sticker 13920 becomes electrically coupled to the metal traces formed on optical disc 13600 using disc hub 13802. Conductive adhesive 13906 enhances this electrical coupling. Thus, die 104 and matching network 13908 become electrically coupled to metal layer 13602 because conductive ring 13910 becomes electrically coupled to the metal traces formed on disc substrate 13610 by feed lines 13902 of disc hub 13802, described above.

Thus, optical disc 13600 can operate as an RFID tagged object, and can respond to interrogations by a reader.

[0408] FIGS. 140A-140C show views of an alternate embodiment for disc hub 13802. As shown in the embodiment of FIGS. 140A-140C, four separate circular feed lines 1002a-d are present in series around the diameter of disc hub 13802. Feed lines 1002a-d do not form a continuous circle around an outer edge of disc hub 13802, as does feed line 13902a shown in FIGS. 139A- 139C. Instead feed lines 1002a-d are discrete, partially circumferential, and are spaced around disc hub 13802. Each feed line 1002a-d has a corresponding radial feed line segment 1004a-d that connects the respective feed line 1002a-d to an outer edge of disc hub 13802. Thus, when metal vapor 13802 is applied to disc hub 13802 of FIG. 140, metal traces are formed on disc substrate 13610 that are not continuous around optical disc 13600.

Furthermore, the metal traces formed on disc substrate 13610 are formed to be coupled to metal layer 13602. Thereafter, an interposer, such as interposer 13920, can be applied as described above, with outer conductive ring 13910 becoming electrically coupled with the metal traces formed by feed lines 14002a-d and 14004a-d, and therefore becoming coupled to metal layer 13602.

[0409] As shown for step 13706 in FIG. 137, after interposer 13920 is applied to an optical disc 13600 (e. g. , after step 13704), a protective coating can be formed on disc 13600 to encapsulate metal layer 13602, interposer 13920, and die 104, if desired.

[0410] Note that additional embodiments for disc hub 13802 will be apparent to persons skilled in the relevant art (s) from the teachings herein.

[0411] FIG. 141 shows further details of an example embodiment for interposer 13920. For example, interposer 13920 includes a matching network patterned on the interposer substrate that is applicable to a 916 MHz DVD.

FIG. 141 is provided for illustrative purposes, and is not limiting. It will be apparent to persons skilled in the relevant art (s) that interposer 13920 can be varied to create matching networks applicable to all varieties of disc medium and signal frequencies. These variations are within the scope and spirit of the present invention.

[0412] In the example embodiment of FIG. 141, an outside diameter 14104 for matching network 13908 is approximately 35 mm. A diameter 14106 of the central insert hole 14102 of interposer 13920 is approximately 14 mm. A distance 14108 from an edge of the central insert hole 14102 to an edge of matching network 13908 is approximately 21 mm. Matching network 13908 includes a circular outer portion, a circular inner portion, and a portion in line with the mounting position of die 104. The outer portion of matching network 13908 forms a circle substantially around interposer 13920. The inner portion of matching network forms a circle substantially around the central insert hole 14102 of interposer 13920. A width 14110 of an outer portion of matching network 13908 is approximately 6 mm. The outer portion of matching network includes a plurality of repeating squared"zig-zag"portions. An outer width 14112 of one zig-zag portion is approximately 4 mm. An inner width 14114 of one zig-zag portion is approximately 1.5 mm. A width 14116 between ends of the outer portion of the matching network 13908 is approximately 7mm. A width 14118 of the portion in line with the mounting position of die 104 is approximately 2 mm.

[0413] FIGS. 142A-142C show example applications for a tagged optical disc 13600, according to embodiments of the present invention. For example, as shown in FIG. 142A, in an embodiment, a tag antenna can be applied between two discs that are combined, such as two DVDs. This brings the effective antenna to both the inside label and the outside edge of the disc. Furthermore, as shown in FIG. 142B, a matching circuit with die/chip can be embedded into a tamper label during manufacturing. As shown in FIG. 142C, source tagging on a disc may be done.

[0414] Note that in an example implementation, once an optical disc 13600 is manufactured, it may be packaged in a shielded optical disc package. Thus, this implementation can operate as a tamper-resistant device. For example, a tagged optical disc 13600 in a shielded package will not be capable of responding to an interrogation. Once the package is opened, the optical disc 13600 can respond to an interrogation. Thus, if someone opens or tampers with a packaged optical disc 13600 before the disc has been legitimately sold, if the optical disc 13600 can be successfully interrogated, a merchant will know that the disc has been tampered with.

7.0 Example Antenna and Web Layout Embodiments [0415] This subsection describes some example antenna layouts and web configurations, according to example embodiments of the present invention.

These embodiments are shown for illustrative purposes, and are not intended to limit the present invention. The present invention is applicable to any antenna layouts and web configurations described elsewhere herein, or otherwise known.

[0416] FIG. 143 shows an example web 14300, according to an embodiment of the present invention. Web 14300 includes a four by six array of tag antennas 14302, although other sized arrays are also possible. Web 14300 may be a complete web sheet, or may be a portion of a larger web. Antennas 14302 are relatively large sized antennas, although can be made in any size.

For example, a die pitch or spacing of antennas 14302 can be 100 mm, or other amounts. FIG. 144 shows further detail of an antenna 14302. FIG. 145 shows further detail of a die mount region 14402 shown in FIG. 144. A die attachment location is shown centrally located in FIG. 145.

[0417] FIG. 146 shows an example web 14600, according to an embodiment of the present invention. Web 14600 includes a nine by ten array of tag antennas 14602, although other sized arrays are also possible. Web 14600 may be a complete web sheet, or may be a portion of a larger web. Antennas 14602 are relatively medium sized antennas, although can be made in any size.

For example, a die pitch or spacing of antennas 14602 can be 40 mm, or other amounts. FIG. 147 shows further detail of an antenna 14602. FIG. 148 shows further detail of a die mount region 14702 shown in FIG. 147. A die attachment location 14802 is shown centrally located in FIG. 148.

[0418] FIG. 149 shows an example web 14900, according to an embodiment of the present invention. Web 14900 includes a 20 by 19 array of tag antennas 14902, although other sized arrays are also possible. Web 14900 may be a complete web sheet, or may be a portion of a larger web. Antennas 14902 are relatively small sized antennas, although can be made in any size. For example, a die pitch or spacing of antennas 14902 can be 20 mm, or other amounts. FIG. 150 shows further detail of a region 15000 of web 14900, showing additional details of antennas 14902. A die attachment location 15002 is shown centrally located in FIG. 150.

[0419] FIG. 151 shows an example antenna interposer 15100, according to an embodiment of the present invention. Antenna interposer 15100 includes substrate, a centrally located die attachment location 15102 for a die 104 having four contacts 204a-d on a first surface of antenna interposer 15100, and four corresponding interconnection segments 15104a-d formed on the substrate of antenna interposer 15100 (not shown in FIG. 151). Furthermore, in embodiments, the substrate of antenna interposer 15100 may include an second, adhesive, surface, similar to a"sticker. "In some embodiments, the adhesive material of the adhesive surface is electrically conductive.

[0420] In embodiments, a die 104 is mounted to die attachment location 15-102 of antenna interposer 15100, such that each of contacts 204a-d are electrically coupled to one of interconnection segments 15104a-d. A protective coating may be applied to the die-attachment surface of antenna interposer 15100 to environmentally protect die 104 on antenna interposer 15100.

[0421] In embodiments, antenna interposer 15100 can subsequently be attached to an antenna larger than antenna interposer 15100, as desired, to create a RFID tag. Antenna interposer 15100 can be attached to the antenna in the manner of a"sticker", or otherwise. Necessary ones of interconnection segments 15104a-d can be coupled to various points of the antenna, to allow for tag and antenna operation. By attaching antenna interposer 15100 to such an antenna, a greater communication range is possible for the resulting RFID tag than with just antenna interposer 15100 alone. Furthermore, in this manner, antennas and antenna interposer 15100 can be manufactured separately, which can result in some manufacturing process benefits.

[0422] Note that antenna interposer 15100 can be formed in any size or shape, as would be understood to persons skilled in the relevant art (s) from the teachings herein. The substrate of antenna interposer 15100 can be made from a polymer, a plastic, glass, a metal or combination of metal/alloy, other material (s), or any combination thereof.

8.0 Conclusion [0423] While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be apparent to persons skilled in the relevant arts that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.