RIGHTS OF THE GOVERNMENT

[0001] The invention described herein may be manufactured and used by or for the

Government of the United States for all governmental purposes without the payment of any royalty.

FIELD OF THE INVENTION

[0002] The present invention relates to processes of making components for electronic and optical devices using laser processing and devices comprising such components.

BACKGROUND OF THE INVENTION

[0003] Device elements (e.g. resistors, capacitors, diodes, sensors, MOSFETs and bipolar junction transistors) within circuits rely on controlling the electron transport within three basic building blocks of electronic materials: insulators, conductors, and semiconductors. It is only through the precise and tedious integration of these three subsets of materials that we realize electronics, as we know them today. Current methods of making components for electronic and optical devices require large-scale clean rooms and are not easily reconfigurable. As a result, rapid device prototyping, design change and evolution is not only difficult in the lab but also prohibitive on the production side. As a result, industry has looked to additive manufacturing processes for a solution. Unfortunately, reproducibility, ink stability, and material limitations remain as barriers to an additive manufacturing solution. In addition to the aforementioned problems, current methods of making components for electronic and optical devices are limited to producing primarily single function components that are later assembled with other components to yield the desired electronic and/or optical functionality. Thus, what is needed is an efficient, easily reconfigurable process of making components for electronic and optical devices that not only can yield single function components but also can yield components with multiple functions that are integrated on the same substrate or film.

[0004] Applicants recognized that lasers could not only be used to remove material from substrates and films but could also be used to induce chemical and/or structural changes in substrates and films with distinct electronic properties. Such recognition lead Applicants to develop a process of making components for electronic and optical devices, devices that can have one or more electronic and/or optical functionalities. Importantly, Applicants process can be used to make structural and/or chemical changes within a fdm or other article that results in an electrical component, an optical component or a combined electrical and optical component being created in such fdm or article. Such process does not require large- scale clean rooms and is easily configurable. Thus, rapid device prototyping, design change and evolution in the lab and on the production side are realized.

SUMMARY OF THE INVENTION

[0005] The present invention relates to processes of making components for electronic and optical devices using laser processing and devices comprising such components. Such process uses a laser to introduce chemical and/or structural changes in substrates and films that are the raw materials from which components for electronic and optical devices are made. Such process yields components that can have one or more electronic and/or optical functionalities that are integrated on the same substrate or film. In addition, such process does not require large-scale clean rooms and is easily configurable. Thus, rapid device prototyping, design change and evolution in the lab and on the production side is realized.

[0006] Additional objects, advantages, and novel features of the invention will be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with a general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.

[0008] FIG. 1A is a schematic depicting a continuous wave laser beam forming patterned structures onto a 900 nm thick amorphous M0S2 film on a glass substrate. [0009] FIG. IB is a processing diagram describing the chemistry and crystalline intensity of areas exposed to a given laser peak intensity (kW/cm ² ) and effective exposure time.

[0010] FIG. 1C are Raman spectrographs of the various crystalline films.

[0011] FIG. 2A depicts a laser written resistor and the change in resistance as the length of the line is increased.

[0012] FIG. 2B depicts a comb capacitor and the range in device capacitance achievable based on the capacitor length and design.

[0013] FIG. 3A shows a response from a laser written gas sensor with the inset being an image of the sensor under test.

[0014] FIG. 3B is an optical image of the laser written sensor, with conducting MoCk, insulating MoCk, and semiconducting M0S2 patterned areas.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

[0015] Unless specifically stated otherwise, as used herein, the terms "a", "an" and

“the” mean "at least one".

[0016] As used herein, the terms "include", "includes" and "including" are meant to be non-limiting.

[0017] As used herein, the words “about,” “approximately,” or the like, when accompanying a numerical value, are to be construed as indicating a deviation as would be appreciated by one of ordinary skill in the art to operate satisfactorily for an intended purpose.

[0018] Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions.

[0019] All percentages and ratios are calculated by weight unless otherwise indicated.

All percentages and ratios are calculated based on the total composition unless otherwise indicated.

[0020] It should be understood that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification will include every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

Processes of Making Components for Electronic and Optical Devices [0021] For purposes of this specification, headings are not considered paragraphs and thus this paragraph is paragraph twenty-one of the present specification. The individual number of each paragraph above and below this paragraph can be determined by reference to this paragraph’s number. In this paragraph twenty -one, Applicants disclose process of making an electrical component, an optical component or a combined electrical and optical component, said process comprising: a) pattern illumination-based annealing at a specific intensity and for a specific time, at least one material that comprises two or more regions that are amorphous, nanocrystalline, microcrystalline or crystalline with the proviso that at least two of said regions are not identical with respect being amorphous, nanocrystalline, microcrystalline or crystalline, said at least one material comprising a transition metal and an element selected from the group consisting of hydrogen, carbon, nitrogen, oxygen, sulfur, selenium, phosphorous and mixtures thereof, using a laser or lamp, to form on, within or on and within said material:

(i) at least two electronic elements selected from a conductor, semiconductor and an insulator;

(ii) two or more different conductors having at least one of the following: different electrical properties or different optical properties;

(iii) two or more different semiconductors having at least one of the following: different electrical properties or different optical properties; or

(iv) two or more different insulators having at least one of the following: different electrical properties or different optical properties; said process being performed under one of the following conditions: vacuum of less 100 torr, air or under a fluid blanket other than air; said pattern illumination-based annealing resulting in at least one of a chemical change or structural change in at least one of said materials that results in an electrical component, an optical component or a combined electrical and optical component being created to form on, within or on and within said material; or b) pattern illumination-based annealing at least one material that comprises at least one region that is amorphous, nanocrystalline, microcrystalline or crystalline, said at least one material comprising a transition metal and an element selected from the group consisting of hydrogen, carbon, nitrogen, oxygen, sulfur, selenium, phosphorous and mixtures thereof, using a laser or lamp, to form on, within or on and within said material:

(i) at least two electronic elements selected from a conductor, semiconductor and an insulator;

(ii) two or more different conductors having at least one of the following: different electrical properties or different optical properties;

(iii) two or more different semiconductors having at least one of the following: different electrical properties or different optical properties; or

(iv) two or more different insulators having at least one of the following: different electrical properties or different optical properties; at least two electronic elements selected from a conductor, semiconductor and an insulator, said process being performed under one of the following environmental conditions: vacuum of less 100 torr, air or under a fluid blanket other than air, then repeating, one or more times said pattern illumination-based annealing on said at least one material using one or more of the following:

(i) the same device but at least one of the following: a different intensity or time;

(ii) a different environmental condition from the previous environmental condition, said different environmental condition select from the same group of environmental conditions; or (iii) a lamp if the previous pattern illumination-based annealing was laser pattern illumination-based annealing or a laser if the previous pattern illumination-based annealing was lamp pattern illumination-based annealing; said pattern illumination-based annealing resulting in at least one of a chemical change or structural change in at least one of said materials that results in an electrical component, an optical component or a combined electrical and optical component being created to form on, within or on and within said material. In one aspect, said process is repeated up to a billion times

[0022] Applicants disclose the process of paragraph twenty-one wherein for process lb) said at least one material comprises two or more regions that are amorphous, nanocrystalline, microcrystalline or crystalline with the proviso that at least two of said regions are not identical with respect being amorphous, nanocry stalline, microcrystalline or crystalline, at least two of said regions being pattern illumination-based annealed via different pattern illumination-based annealing processes. Here, each such process is still within the scope of Paragraph 22 ’s processing conditions.

[0023] Applicants disclose the process of paragraphs twenty-one through twenty-two wherein, said transition metal is selected from the group consisting of molybdenum, tungsten, niobium, tantalum, vanadium, titanium, chromium, iron, rhodium, hafnium, rhenium and mixtures thereof.

[0024] Applicants disclose the process according to paragraph twenty-one through twenty -three, wherein said process is performed under a fluid blanket other than air.

[0025] Applicants disclose the process according to paragraphs twenty-one through twenty-four wherein, said fluid blanket comprises: a) an element selected from the group consisting of krypton, xenon, radon, argon, neon, helium, hydrogen, carbon, nitrogen, oxygen, sulfur, selenium, phosphorous and mixtures thereof; b) based on total fluid volume greater than 0% to about 19% or from 21% to 100% oxygen; and/or c) greater than 0% to about 78% or from 80% to 100% nitrogen.

[0026] Applicants disclose the process according to paragraphs twenty-one through twenty -five wherein, said material comprises at least one region that is amorphous or nanocry stalline. [0027] Applicants disclose the process according to paragraphs twenty-one through twenty-six wherein, said pattern illumination-based annealing is achieved by using a laser to subject said material for a time of about 1 femtosecond to 60 seconds, said laser having power of from about 1 W/cm ² to about 1 x 10 ¹⁵ W/cm ² over said time of about 1 femtosecond to 60 seconds.

[0028] Applicants disclose the process of paragraphs twenty-one through twenty-six wherein, said pattern illumination-based annealing is achieved by using a continuous wave laser to subject said material for a time of about 0.1 milliseconds to 60 seconds to said laser, said laser having power of from about 1 W/cm ² to about 1 x 10 ⁸ W/cm ² over said time of about 0.1 milliseconds to 60 seconds.

[0029] Applicants disclose the process of paragraphs twenty-one through twenty-six wherein, said pattern illumination-based annealing is achieved by using a continuous wave laser to subject said material for a time of about 1 femtosecond to 60 seconds to said laser, said laser having power of from about lxlO ⁸ W/cm ² to about 1 x 10 ¹⁶ W/cm ² over said time of about 1 femtosecond to 60 seconds.

[0030] Applicants disclose the process of paragraphs twenty -one through twenty -nine wherein, said material comprises a film having a thickness of from about 0.1 nanometers to about 1 centimeter, preferably film has a thickness of from about 0.3 nanometers to about 10 micrometers

[0031] Applicants disclose the process of paragraphs twenty-one through thirty wherein, said electrical device, an optical device or a combined electrical and optical device is selected from the group consisting of an inductor, a capacitor, a resistor, a diode, a transistor, a trace, a battery, an optical filter, and a solar cell.

[0032] Applicants disclose process of making electrical device, an optical device or a combined electrical and optical device, said process comprising combining: a) two or more electrical, an optical or a combined electrical and optical components produced according to a process of paragraphs twenty-one through thirty; or b) at least one electrical, optical or combined electrical and optical component produced according to a process paragraphs twenty-one through thirty, and one or more additional electrical, optical or combined electrical and optical components. Said one or more additional electrical, optical or combined electrical and optical components are not produced according to the processes of paragraphs twenty -one through thirty. [0033] Applicants disclose an electrical device, an optical device or a combined electrical and optical device: a) on, within or on and within at least one material that comprises two or more regions that are amorphous, nanocrystalline, microcrystalline or crystalline with the proviso that at least two of said regions are not identical with respect being amorphous, nanocrystalline, microcrystalline or crystalline, said at least one material comprising a transition metal and an element selected from the group consisting of hydrogen, carbon, nitrogen, oxygen, sulfur, selenium, phosphorous and mixtures thereof; or b) on, within or on and within at least one material that comprises at least one region that is amorphous, nanocrystalline, microcrystalline or crystalline, said at least one material comprising a transition metal and an element selected from the group consisting of hydrogen, carbon, nitrogen, oxygen, sulfur, selenium, phosphorous and mixtures thereof. Said electrical device, an optical device or a combined electrical and optical device being, in one aspect, produced according to the processes of paragraphs twenty-one through thirty.

[0034] Suitable amorphous, nanocrystalline, microcrystalline and/or crystalline materials comprising a transition metal and hydrogen, carbon, nitrogen, oxygen, sulfur, selenium, tellurium, and/or phosphorous can be obtained from Plasmaterials (2268 Research Drive, Livermore, CA 94550 USA) and Kurt Lesker (1925 Route 51, Jefferson Hills, PA 15025 USA.

[0035] Suitable lasers for conducting Applicants can be obtained from Thorlabs (56

Sparta Avenue, Newtown, NJ 07860 USA) and Coherent (5100 Patrick Henry Dr., Santa Clara, CA 95054 USA).

Devices Comprising Electronic and/or Optical Components [0036] The components for electronic and optical devices that are made by

Applicants’ process can be used in a variety of electronic and optical devices. In general such electronic and optical devices are produced by incorporating one or more of the components made by Applicants’ processes into the subject electronic and/or optical devices. Suitable ways of incorporating current components, made by processes other than Applicants’ processes, are provided in USPN 3,138,743 that relates to miniaturized electronic circuits, USPN 5,515,241 that relates connecting integrated circuits and USPN 5,526,280 that relates to a gas sensor circuit. Examples

[0037] The following examples illustrate particular properties and advantages of some of the embodiments of the present invention. Furthermore, these are examples of reduction to practice of the present invention and confirmation that the principles described in the present invention are therefore valid but should not be construed as in any way limiting the scope of the invention.

[0038] Example 1 : Laser Written resistor and capacitor in thin film molybdenum disulfide. A molybdenum disulfide (M0S2) thin film of thickness totaling 900 ± 50 nm was deposited onto a glass or S1O2 wafer via magnetron sputtering using a 99.95% pure M0S2 target. Deposition at room temperature resulted in an amorphous film (referred to as -MoS2) comprised of pure M0S2 and little to no evidence of crystalline structure. Exposure of the a- M0S2 to the laser intensities between 1 and 12 kW/cm ² and exposure times between 0.01 and 10 seconds resulted in the formation of distinct chemical phases, schematically depicted in FIG. 1A. Specifically, the formation of crystalline 2H-M0S2, M0O2, and M0O3 were observed. This is illustrated in FIG. IB where the normalized Raman signal for distinct peaks associated with each phase are plotted as a function of intensity and exposure time. Each of the points in FIG. IB correspond to the phase formed at the center of a line written under the specified conditions; further from the center, the intensity is lower and can result in the formation of a separate phase. With the ability to locally create crystalline M0S2, M0O2, and M0O3, patterns utilizing the vastly different electronic properties enabled passive circuit elements to be created. One instance of this was through the direct laser writing of resistors and capacitors using a 514 nm laser and creating conducting M0O2 patterns and insulating M0O3 isolation. Depicted in FIG. 2A, resistance can be controlled in a resistor component by varying the length of conductive material within the amorphous material, with the required M0O3 isolation surrounding. Additionally, comb capacitors shown in FIG. 2B with tailored electronic properties are possible via patterning of the same materials but in different configurations.

[0039] Example 2: Gas sensor laser written in molybdenum disulfide

Active circuit elements were also possible using the laser writing technique by taking advantage of the on/off properties of semiconducting 2H-M0S2. One example of this is the laser writing of a chemresistor style gas sensor shown in FIG. 3A and FIG. 3B that can detect ammonia at sub 10 ppm levels. This chemresistor was composed of a semiconducting crystalline M0S2 channel, M0O2 contact pads and electrodes, and a M0O3 boundary isolation and was demonstrated to detect 10, 100, and 1000 parts per million of NH3 gas.

[0040] Example 3 : The first five materials listed in Column 3 of Table 1 below were made in accordance with Applicants’ process using a laser and then the same results were obtained using a lamp. Such materials are useful as listed in Column 5 of Table 1. The last 6 materials listed in Column 3 of Table 1 below are made in accordance with Applicants’ process using a laser and then the same results were obtained using a lamp. Such materials are useful as listed in Column 5 of Table 1. The Examples 1, 2, 5, 9 and 10 show a crystalline structure changes in the starting material as represented by 2H, IT, T-Phase and H-Phase while Examples 3, 4, 6, 7, 8 and 9 show a chemical change in the starting material.

Table 1

[0041] Example 4. P-N junction with laser written MoS2/WSe2

Lateral P-N junctions are made possible through patterned amorphous deposition of in-plane heteijunctions of amorphous MoS2/WSe2 structures. With the use of one laser pass across the interface, a n-type semiconductor MoS2 is in contact with a p-type WSe2 semiconductor material, forming a P-N junction of use for light emitting diodes (LEDs) and other optical/electronic components.

[0042] Every document cited herein, including any cross referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern. [0043] While the present invention has been illustrated by a description of one or more embodiments thereof and while these embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and process, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept.

-l i