Description

APPARATUS FOR INSPECTION OF SEMICONDUCTOR DEVICE AND METHOD FOR INSPECTION BY THE SAME

Technical Field

[1] The present invention relates to an apparatus for inspection of semiconductor device in which cleaners are integrally mounted to remove fine dust or impurities attached to the exterior of semiconductor devices, thereby reducing the number of semiconductor devices which have been determined to be defective due to contaminants, and consequently, improving a yield of semiconductor devices, and an method for inspection of semiconductor device by the same. Background Art

[2] A semiconductor integrated circuit, which takes the form of a chip on a semiconductor wafer, is processed, via a series of packaging processes, into a semiconductor package suitable to protect the chip from external shock. After completing the packaging processes, the semiconductor package is finally subjected to an electrical functionality test, prior to being supplied to consumers.

[3] The semiconductor package, having passed through the electrical functionality test, is moved to marking equipment, to mark a variety of information (semiconductor chip type, manufacturer, trade name, etc.) thereon.

[4] Generally, even minute exterior appearance defects as well as interior defects fatally affect the performance of such a semiconductor package. Therefore, the semiconductor package must be subjected to an exterior appearance inspection using vision-cameras, in addition to the above-described electrical functionality test.

[5] As to the above-mentioned exterior appearance defects of a semiconductor package, defects in Ball Grid Arrays (BGAs) and leads, in particular, may occur in the course of assembling the semiconductor device to a Printed Circuit Board (PCB), etc. Therefore, inspection of leads or balls and a marking inspection are very important.

[6] A conventional apparatus for inspecting the exterior appearance of a semiconductor package is disclosed in Korean Patent Laid-Open Publication No. 2005-48584, which was filed by the applicant of the present invention and is entitled "Semiconductor Device Inspecting Apparatus".

[7] The disclosed conventional semiconductor device inspecting apparatus, as shown in

FIG. 9, includes: a body 100; a loader 210, on which trays, receiving semiconductor devices to be inspected, are loaded; an inspecting device 300 to inspect semiconductor devices; a buffer 220 to temporarily store a buffer tray, in which inspected semiconductor devices are received; first to third reject carriers 230, 240, and 250, on

which trays, receiving semiconductor devices sorted as defective based on inspection results, are loaded, the defective semiconductor devices received in the trays of the respective reject carriers being sorted according to defect kind; an un-loader 260, on which trays, receiving semiconductor devices sorted as normal based on inspection results, are loaded; a plurality of tray conveyers 480 connected, respectively, to the loader 210, buffer 220, first to third reject carriers 230, 240, and 250, and un-loader 260, to enable movements of trays in forward and rearward directions of the body 100; a transfer device 500 installed at the upper side of the body 100 in a horizontally reciprocally movable manner, to transfer trays between the tray conveyors 480 of the loader 210, buffer 220, first to third reject carriers 230, 240, and 250, and un-loader 260; and a sorting device 600 installed to reciprocally move between the tray conveyors 480 of the buffer 220, first to third reject carriers 230, 240, and 250, and un- loader 260, the sorting device 600 being used to pick up defective semiconductor devices received in the tray to be transferred to the un-loader 260 and transfer the respective defective semiconductor devices to any one of the first to third reject carriers 230, 240, and 250 based on defect type, and also, being used to pick up normal semiconductor devices received in the buffer tray and fill empty space of the tray to be transferred to the un-loader 260 with the normal semiconductor devices.

[8] Here, the inspecting device 300 includes first and second vision-cameras 310 and

320 to perform a vision inspection. The first vision-camera 310 is used to inspect one surface of the respective semiconductor devices received in the tray loaded on the loader 210. The second vision-camera 320 is used to inspect the other surface of the respective semiconductor devices.

[9] To allow both the surfaces of the semiconductor devices to be sequentially inspected by the first and second vision-cameras 310 and 320, the above-described conventional inspecting apparatus further includes an inverting device 700, which is provided between the first vision-camera 310 and the second vision-camera 320 and is used to turn the tray, in which the semiconductor devices are received, upside down.

[10] In FIG. 9, reference numeral 420 represents an empty tray, reference numeral 410 represents a loading stacker, reference numeral 470 represents a feeder on which the empty tray is placed, and reference numerals 430, 440, 450, and 460 represent feeders placed on the first, second, and third reject carriers 230, 240, and 250 and un-loader 260, respectively. Also, reference numeral 610 represents a sorter to sort the semiconductor devices.

[11] With the above-described configuration, while a tray, which is supplied from the loader 210, is transferred along the tray conveyor 480 of the loader 210, one surface of the respective semiconductor devices received in the tray is subjected to a vision inspection via the first vision-camera 310. After completing the vision inspection, the

semiconductor devices are turned upside down by the inverting device 700.

[12] Here, the inverting device 700 must have an empty tray, to allow the semiconductor devices, received in the loader tray, to be newly received in the empty tray in the course of turning the semiconductor devices upside down in such a manner that the other surface of the respective semiconductor devices is exposed.

[13] The tray, in which the inverted semiconductor devices are received, is transferred to any one of the tray conveyors 480 within an inspecting region of the second vision- camera 320 by the transfer device 500, which reciprocally transfers the tray between the tray conveyors 480. The semiconductor devices, which were transferred to the inspecting region after being turned upside down, are subjected to a vision inspection using the second vision-camera 320.

[14] However, the above-described conventional semiconductor device inspecting apparatus has a problem in that fine dust may be attached to the exterior of the semiconductor devices during transfer of the semiconductor devices. In particular, in the ca se of lead type semiconductor devices, specific impurities such as lead may remain on the exterior of the semiconductor devices.

[15] The semiconductor devices, on which fine dust or impurities remain, have a high risk of being determined to be defective according to results of the vision inspections using the vision-cameras, despite their being normal semiconductor devices. Therefore, there are problems of deteriorated inspection accuracy and low yield.

[16] To solve the above problems, it has been conventionally proposed to perform a vision inspection after removing fine dust or impurities by manually blowing air onto semiconductor devices determined which have been determined to be defective, or by manually cleaning the respective semiconductor devices one by one using brushes, etc. These manual cleaning operations, however, excessively extend inspection time, resulting in deteriorated in productivity and increasing a product price due to increased labor costs.

Disclosure of Invention Technical Problem

[17] Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an apparatus for inspection of semiconductor device, in which an air cleaner is provided at a leading end of a vision camera to automatically remove contaminants such as dust or impurities present on the exterior of semiconductor devices, thereby preventing normal semiconductor devices from being erroneously determined to be defective due to the contaminants, and consequently, achieving improved yield and inspection accuracy, and a semiconductor device inspecting method using the same.

[18] It is another object of the present invention to provide an apparatus for inspection of semiconductor device, in which a brush cleaner is operated when a reject tray, which receives defective semiconductor devices, is returned for re-inspection, to automatically remove impurities or dust present on the exterior of the semiconductor devices prior to performing a vision inspection of the semiconductor devices, thereby preventing normal semiconductor devices from being erroneously determined to be defective due to minute surface defects, and an method for inspection of semiconductor device by the same. Technical Solution

[19] In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of an apparatus for inspection of semiconductor device, in which the exterior of semiconductor devices, which are received in a tray, is photographed by a vision inspecting device, to sort the semiconductor devices, on the basis of analyzed results of photographed images, into defective semiconductor devices and normal semiconductor devices, the defective semiconductor devices being sorted and transferred, on the basis of defect type, to a plurality of reject carriers, and the normal semiconductor devices being transferred to an un-loader, wherein The apparatus for inspection of semiconductor device comprises air cleaners to automatically remove contaminants present on the exterior of the semiconductor devices by use of air, prior to performing a vision inspection using the vision inspecting device.

[20] The vision inspecting device may include a first vision-camera and a second vision- camera, and the air cleaners may be provided at leading ends of the first and second vision-cameras, respectively.

[21] Each of the air cleaners may include: a housing formed, at a lower surface thereof, with an opening and, at an upper surface thereof, with a plurality of holes; a plurality of vacuum suction tubes fitted into the holes, respectively; and an air discharge tube horizontally inserted into the lower opening of the housing, the air discharge tube being formed, at a lower surface thereof, with a plurality of discharge holes formed obliquely by a predetermined angle.

[22] Preferably, the housing has a dome shape to assure smooth suction of impurities and dust through the vacuum suction tubes.

[23] An ion supply device may be connected to the air discharge tube, to supply ions for prevention of electrostatic charge, and the air cleaner may further include a flow-rate adjusting valve and a pressure adjusting valve to automatically adjust the flow rate and pressure of air to be supplied into the air discharge tube, according to the kind of semiconductor device.

[24] Each of the air cleaners may further include a sensor to sense whether or not the

semiconductor devices are normally received in the tray.

[25] The apparatus for inspection of semiconductor device may further comprise: a brush cleaner to automatically remove contaminants present on the exterior of the semiconductor devices, prior to performing a vision inspection using the vision inspecting device.

[26] The brush cleaner may be operated when a tray loaded on an associated one of the reject carriers is returned for re-inspection, and the brush cleaner may include: a brush module integrally formed with a plurality of brushes; a housing mounted at a rear side of the brush module, the housing being formed, at a lower surface thereof, with an opening and, at an upper surface thereof, with a plurality of holes; a plurality of vacuum suction tubes fitted into the holes, respectively; and an air discharge tube horizontally inserted into the lower opening of the housing to receive air supplied thereto, the air discharge tube being formed, at a lower surface thereof, with a plurality of discharge holes formed obliquely by a predetermined angle.

[27] Preferably, the brush cleaner may further include a shield member provided at the lower opening of the housing and configured to reduce an air suction space for increasing a vacuum suction force.

[28] The ion supply device may be further connected to the air discharge tube of the brush cleaner, to supply ions for prevention of electrostatic charge, and the brush cleaner may further include a tension adjustor to maintain an appropriate tension with the semiconductor devices.

[29] In accordance with another aspect of the present invention, there is provided an method for inspection of semiconductor device comprising: transferring a tray, in which semiconductor devices are received such that first surfaces of the semiconductor devices are oriented upward, from a loader to a first vision inspecting region; performing a first vision inspection on the first surfaces of the semiconductor devices; and sorting the semiconductor devices into defective semiconductor devices and normal semiconductor devices on the basis of results of the first vision inspection, wherein The method for inspection of semiconductor device further comprises:, prior to transferring the tray to the first vision inspecting region, performing an air cleaning operation on the semiconductor devices received in the tray.

[30] The method for inspection of semiconductor devicemay further comprise:, after performing the first vision inspection and before sorting the semiconductor devices into defective semiconductor devices and normal semiconductor devices on the basis of results of the vision inspection, turning the semiconductor surfaces received in the tray upside down such that second surfaces of the semiconductor devices are oriented upward; performing an air cleaning operation on the second surfaces of the semiconductor devices; transferring the tray, in which the semiconductor devices, having

passed through the air cleaning operation, are received, to a second vision inspecting region; and performing a second vision inspection on the second surfaces of the semiconductor devices received in the tray transferred to the second vision inspecting region.

[31] The method for inspection of semiconductor device may further comprise: returning a tray, in which the semiconductor devices sorted as defective semiconductor devices are received, toward the loader, and performing a brush cleaning operation on the second surfaces of the semiconductor devices received in the returned tray; turning the tray, in which the semiconductor devices, having passed through the brush cleaning operation, are received, upside down, such that the first surfaces of the semiconductor devices are oriented upward; performing a brush cleaning operation on the first surfaces of the semiconductor devices; and performing an additional vision inspection after loading the tray, in which the semiconductor devices, having passed through the brush cleaning operation, are received, on the loader. Brief Description of the Drawings

[32] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[33] FIG. 1 is a perspective view illustrating an apparatus for inspection of semiconductor device according to a first embodiment of the present invention

[34] FIG. 2 is a partial perspective view of FIG. 1

[35] FIG. 3 is a plan view of FIG. 2

[36] FIG. 4 is a front perspective view illustrating an air cleaner according to an exemplary embodiment of the present invention

[37] FIG. 5 is a bottom view of FIG. 4

[38] FIG. 6 is a perspective view illustrating an apparatus for inspection of semiconductor device according to a second embodiment of the present invention

[39] FIG. 7 is a front perspective view illustrating an embodiment of a brush cleaner shown in FIG. 6;

[40] FIG. 8 is a rear perspective view of the brush cleaner shown in FIG. 6; and

[41] FIG. 9 is a view illustrating a conventional semiconductor device inspecting apparatus. Best Mode for Carrying Out the Invention

[42] Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, to allow those skilled in the art to easily understand and reproduce the present invention.

[43] FIG. 1 is a perspective view illustrating an apparatus for inspection of semi-

conductor device according to a first embodiment of the present invention. FIG. 2 is a partial perspective view of FIG. 1. FIG. 3 is a plan view of FIG. 2.

[44] Referring to FIGS. 1 to 3, the present invention provides an apparatus for inspection of semiconductor device, in which the exterior of semiconductor devices, which are received in a loader tray supplied from a loader L, is photographed by a vision inspecting device 1, to sort the semiconductor devices, on the basis of analyzed results of photographed images, into defective semiconductor devices and normal semiconductor devices, the defective semiconductor devices being sorted and transferred, on the basis of defect type, to a plurality of reject carriers R, and the normal semiconductor devices being transferred to an un-loader U. The apparatus for inspection of semiconductor device of the present invention further includes air cleaners 3 to automatically remove contaminants present on the exterior of the semiconductor devices by use of air, prior to performing a vision inspection using the vision inspecting device 1.

[45] In the drawings, reference numeral "2" represents a sorting device to sort the semiconductor devices, and reference letter "E" represents an empty tray. All constituent elements of The apparatus for inspection of semiconductor device except for the air cleaners 3 are identical to those of the previously described prior art, and a description of the identical constituent elements and operations thereof will be omitted.

[46] The vision inspecting device 1 includes a first vision-camera 11 to inspect one surface of the respective semiconductor devices received in the loader tray, and a second vision-camera 12 to inspect the other surface of the semiconductor devices. The air cleaners 3 are provided at leading ends of both the first and second vision-cameras 11 and 12, respectively.

[47] The semiconductor devices, which are received in the tray transferred from the loader L in such a manner that their lower surfaces are oriented upward, can be cleaned while passing through the air cleaner 3 provided at the leading end of the first vision- camera 11, prior to being subjected to a vision inspection using the first vision-camera 11.

[48] Then, the semiconductor devices are turned upside down by an inverting device

(not shown) such that upper surfaces of the semiconductor devices are oriented upward. As a tray receiving the semiconductor devices passes through the air cleaner 3 provided at the leading end of the second vision-camera 12, the semiconductor devices can be cleaned, prior to being subjected to a vision inspection using the second vision- camera 12.

[49] As described above, by suctioning and removing contaminants such as impurities or dust prior to performing vision inspections, the present invention can prevent normal semiconductor devices from being erroneously determined to defective due to the contaminants on the basis of results of the vision inspections.

[50] FIG. 4 is a front perspective view illustrating an air cleaner according to an exemplary embodiment of the present invention, and FIG. 5 is a bottom view of FIG. 4. The air cleaner 3 includes a housing 31, a plurality of vacuum suction tubes 32, an air discharge tube 33, and an air supply tube 34.

[51] The housing 31 is formed, throughout a lower surface thereof, with an opening, and at an upper surface thereof, with a plurality of holes 311. Preferably, the housing 31 has a dome shape, to allow impurities and dust contained in air to be smoothly suctioned through the vacuum suction tubes 32 without being accumulated at corners of the housing 31.

[52] The vacuum suction tubes 32 to suction air are fitted into the holes 311 of the housing 31, respectively.

[53] Here, if only one vacuum suction tube 32 is provided or a plurality of vacuum suction tubes 32 are clustered in a particular region of the housing 31, the impurities and dust contained in the suctioned air may accumulate in the particular region of the housing 31 rather than completely passing through the housing 31. To prevent this problem, it is preferable that the plurality of vacuum suction tubes 32 be uniformly distributed throughout the housing 31 rather than being clustered in a particular region of the housing 31.

[54] The air discharge tube 33 is horizontally inserted into the lower opening of the housing 31. The air discharge tube 33 is formed, at a lower surface thereof, with a plurality of discharge holes 331 such that the discharge holes 331 are formed obliquely by a predetermined angle. The air supply tube 34 is connected to the air discharge tube 33 through an air port 332 formed at one end of the air discharge tube 33, to supply air into the air discharge tube 33.

[55] The air, supplied into the air discharge tube 33, is discharged to the outside through the air discharge holes 331, to remove contaminants such as impurities or dust attached to the surfaces of the semiconductor devices. The vacuum suction tubes 32 serve to suction the removed contaminants via vacuum suction.

[56] Preferably, the air supply tube 34 is connected with anion supply tube 35, which is, in turn, connected to an ion supply device (not shown) to supply ions for prevention of electrostatic adsorption of contaminants.

[57] Generally, the surfaces of the semiconductor devices are contaminated with dust or impurities attached thereto by electrostatic adsorption, and it is difficult to remove the electrostatic adsorbed dust or impurities using air.

[58] For this reason, in the present invention, it is preferable that the electrostatic surfaces of the semiconductor devices be neutralized by the supply of ions through the ion supply tube 35, to enable easy removal of the dust or impurities adsorbed to the surfaces of the semiconductor devices.

[59] Although not shown in the drawings, the air cleaner 3 preferably further includes a flow-rate adjusting valve and a pressure adjusting valve, to automatically adjust the flow rate and pressure of air according to the kind of semiconductor device. The flow- rate adjusting valve and pressure adjusting valve are connected to a personal computer for automatic remote control thereof.

[60] For example, in general, objects to be inspected, i.e. respective semiconductor devices have different kinds of elements such as balls or leads.

[61] Therefore, if the same-air pressure is applied in all cases, it may cause damage to the elements mounted on the semiconductor devices. For this reason, it is preferable to adjust the flow rate and pressure of air.

[62] The air cleaner 3 further includes a sensor 36 to sense whether or not the semiconductor devices are normally received in the tray.

[63] According to the above-described first embodiment of the present invention, with the use of the air cleaners provided at the leading ends of the vision-cameras to automatically remove contaminants such as dust or impurities present on the exterior of the semiconductor devices, the present invention has the effects of preventing normal semiconductor devices from being erroneously determined to be defective due to the contaminants, and consequently, achieving improved yield and inspection accuracy.

[64] FIG. 6 is a perspective view illustrating an apparatus for inspection of semiconductor device according to a second embodiment of the present invention. Hereinafter, a description of the same constituent elements as FIG. 1 will be omitted.

[65] Referring to FIG. 6, The apparatus for inspection of semiconductor device according to the second embodiment of the present invention further includes a brush cleaner 4, to automatically remove contaminants such as dust or impurities present on the exterior of semiconductor devices, prior to performing a vision inspection using the vision inspecting device 1 (See FIG. 1).

[66] Preferably, the brush cleaner 4 is operated when the tray loaded on the reject carrier

R is returned for re-inspection.

[67] More specifically, once the semiconductor devices, which were determined to be defective based on results of the vision inspections, are received in the tray on the reject carrier R, the reject tray is returned for re-inspection. In this case, prior to performing the re-inspection, the upper surfaces of the semiconductor devices are cleaned by use of the brush cleaner 4. Thereafter, the semiconductor devices are turned upsidedown by use of the inverting device (not shown).

[68] By operation of the inverting device (not shown), the semiconductor devices are received in a tray such that their lower surfaces are oriented upward. After the semiconductor devices are cleaned by use of the brush cleaner 4, the tray is loaded on the loader L, and is subjected to re-inspection.

[69] Preferably, the brush cleaner 4 is an antistatic brush to prevent electrostatic charge due to contact with the semiconductor devices.

[70] FIG. 7 is a front perspective view illustrating an embodiment of the brush cleaner shown in FIG. 6, and FIG. 8 is a rear perspective view of the brush cleaner shown in FIG. 6. The brush cleaner 4 includes a brush module 41, a housing 42, a plurality of vacuum suction tubes 43, and an air discharge tube 44.

[71 ] The brush module 41 is integrally provided with a plurality of brushes 411. A pair of tension adjustors 45 are coupled to both ends of the brush module 41. Each tension adjustor 45 is inserted into a guide member 46.

[72] Although the above-described embodiment uses the brushes 411 designed to clean surfaces of semiconductor devices via sliding movements thereof, it will be appreciated that another embodiment of the present invention may use rotary brushes designed to be rotated by operation of a motor.

[73] Also, although not shown in the drawings, the tension adjustor 45 preferably incorporates a tension member such as a spring therein, to maintain an appropriate preload between the brush module and the semiconductor devices.

[74] When semiconductor devices are transferred while being received in the tray, they may have different heights according to the kind thereof. Therefore, in the case where it is impossible to adjust a preload between the brush module 41 and surfaces of the semiconductor devices, the brushes 411 are brought into excessively close contact with the semiconductor devices, causing scratches on the surfaces of the semiconductor devices, or causing defects such as separation of BGAs or damage to leads. Conversely, in the case where the brushes 411 fail to come into close contact with the semiconductor devices, it results in insufficient cleaning of the semiconductor devices.

[75] For this reason, it is preferable to provide the appropriate tension adjustors 45 selected according to the kind of object to be inspected, i.e. semiconductor packages.

[76] Preferably, the tension adjustor 45 is moved vertically by a cylinder, which is moved in response to a control signal from a personal computer according to the type of semiconductor devices, so as to adjust the height of the brush module 41.

[77] The housing 42 is mounted at a rear side of the brush module 41. The housing 42 is formed, throughout a lower surface thereof, with an opening, and, at an upper surface thereof, with a plurality of holes 421. The vacuum suction tubes 43 to suction air are fitted into the holes 421 of the housing 42, respectively.

[78] The air discharge tube 44 is horizontally inserted into the lower opening of the housing 42. The air discharge tube 44 is formed at a lower surface thereof with a plurality of discharge holes 441 such that the discharge holes 441 are formed obliquely by a predetermined angle. If air is supplied into the air discharge tube 44 through an air port 442 provided at one end thereof, the air can be discharged to the outside through

the air discharge holes 441.

[79] Preferably, the air port 442 is connected with an ion supply device (not shown) to supply ions for prevention of electrostatic contact with the semiconductor devices.

[80] Generally, when surfaces of semiconductor devices are cleaned by use of the brushes, there is a risk that electric characteristics of the semiconductor devices may be deteriorated due to electrostatic contact with the brushes. Furthermore, the brush cleaner and air cleaners cannot easily remove dust or impurities attached to the semiconductor devices by electrostatic adsorption.

[81] For this reason, in the present invention, it is preferable that the ion supply device

(not shown) supply ions, to prevent electrostatic contact between the brushes and the semiconductor devices during a brush cleaning operation for achieving improved electric reliability, and also, to neutralize the electrostatic surfaces of the semiconductor devices for enabling easy removal of dust or impurities attached to the surfaces of the semiconductor devices by electrostatic adsorption.

[82] The brush cleaner 4 further includes a shield member 47 provided at the lower opening of the housing 42.

[83] The shield member 47 occupies an air suction space of the lower opening of the housing 42, and more particularly, serves to reduce an extra space in the vicinity of the air discharge tube 44. Such a space reduction has the effect of increasing a vacuum suction force of the vacuum suction tubes 43. Accordingly, the shield member 47 can assure more efficient suction and removal of impurities or dust generated during the cleaning operation using the brushes 411.

[84] According to the above-described second embodiment of the present invention, with the use of the brush cleaners provided to automatically remove dust or impurities present on the exterior of the semiconductor devices, prior to again performing a vision inspection of the semiconductor devices, the present invention has the effect of preventing normal semiconductor devices from being erroneously determined to be defective due to minute surface defects.

[85] Herein after, an method for inspection of semiconductor device using the above- described semiconductor device inspecting apparatus according to the present invention will be described in brief.

[86] First, trays, in which semiconductor devices are received such that their first surfaces are oriented upward, are loaded on the loader L.

[87] Then, the trays loaded on the loader L are sequentially transferred to a vision inspecting region. In this case, the first surfaces of the semiconductor devices are subjected to a cleaning operation using the air cleaner 3, prior to being transferred to a first vision inspecting region.

[88] After performing a vision inspection on the first surfaces of the semiconductor

devices received in the tray by use of the first vision-cameral 1, the tray is turned upside down by use of the inverting device (not shown) such that second surfaces of the semiconductor devices are oriented upward.

[89] Then, a tray, in which the semiconductor devices are received such that their second surfaces are oriented upward, is transferred to a second vision inspecting region. In this case, prior to being transferred to the second vision inspecting region, the second surfaces of the semiconductor devices are subjected to a cleaning operation using the air cleaner 3.

[90] After performing a vision inspection using the second vision-camera 12, on the basis of results of the vision inspection, the semiconductor devices are sorted into normal semiconductor devices to be transferred to the un-loader U, and defective semiconductor devices to be transferred to the reject carriers R.

[91] Meanwhile, after the defective semiconductor devices are received in a reject tray loaded on the reject carrier R, the reject tray is returned toward the loader, so as to be subjected to a vision inspection.

[92] More specifically, while the reject tray, in which the semiconductor devices are received such that their second surfaces are oriented upward, is transferred to the loader, the second surfaces of the semiconductor devices are cleaned by use of the brush cleaner 4.

[93] In this case, according to defect type of the semiconductor devices determined to be defective, the reject carriers R can be classified into different reject regions Rl, R2, R3, and B. The above-described brush cleaning operation is performed on a specific reject tray, in which the semiconductor devices having surface defects are received.

[94] For example, when semiconductor devices having surface defects are received in the reject region R2, the brush cleaner 4 is installed on the tray conveyer extending from the reject region R2, and the reject tray loaded on the reject region R2 is returned to ready a brush cleaning operation.

[95] Although the embodiment of the present invention describes that the semiconductor devices having the surface defects are sorted onto the reject region R2 and the brush cleaner 4 is installed on the tray conveyer extending from the reject region R2, the present invention is not limited thereto, and the sorting region of semiconductor devices having surface defects and installation position of the brush cleaner can be realized in various manners in other various embodiments of the present invention.

[96] Meanwhile, after completing the cleaning of the second surfaces of the semiconductor devices, the tray is turned upside down by use of the inverting device (not shown) such that the first surfaces of the semiconductor devices are oriented upward.

[97] Then, the first surfaces of the semiconductor devices are cleaned by use of the brush cleaner 4, and the tray, which receives the cleaned semiconductor devices, is loaded on

the loader L.

[98] Thereafter, a vision inspection for all the returned trays is performed.

[99] According to the above-described semiconductor device inspecting method of the present invention, as a result of performing air cleaning operations prior to performing respective vision inspections on first and second surfaces of semiconductor devices, it is possible to prevent any vision inspection error due to contaminants. Also, by additionally performing a brush cleaning operation on semiconductor devices which have been determined to be defective, it is possible to remove contaminants which are not removed by the air cleaning operation, prior to performing an additional vision inspection. This achieves improved inspection accuracy. Industrial Applicability

[100] As apparent from the above description, the present invention provides the following several effects.

[101] Firstly, according to the present invention, an air cleaner is provided at a leading end of each vision-camera to automatically remove contaminants such as dust or impurities present on the exterior of a semiconductor device. This has the effect of preventing normal semiconductor devices from being erroneously determined to be defective due to the contaminants, thereby achieving improved yield and inspection accuracy.

[102] Secondly, according to the present invention, as a result of providing a reject carrier with a brush cleaner, it is possible to automatically remove contaminants such as dust or impurities present on the exterior of the semiconductor devices, prior to performing an additional vision inspection. This has the effect of preventing normal semiconductor devices from being determined to be defective due to minute surface defects.

[103] Thirdly, the provision of an ion supply device connected to the air cleaner and brush cleaner prevents electrostatic charge during cleaning operations, and consequently, preventing deterioration of electric characteristics of semiconductor devices. Also, the supply of ions can allow dust or impurities, which are attached to the surfaces of the semiconductor devices by electrostatic adsorption, to be easily removed via neutralization of the electrostatic force.

[104] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.