JP2009121894A - Method and device for inspecting defect of conductor pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for inspecting a conductor pattern that dispense with acquisition of the whole substrate image, capable of detecting a defective spot on the transparent conductor pattern in a short time. <P>SOLUTION: A probe 15a is connected to each left end of odd-numbered conductor patterns 31, and a probe 15b is connected to each right end of even-numbered conductor patterns 31, and a prescribed voltage is applied between the probes 15a, 15b. When some conductor pattern 31 has a short circuit defect, a current flows through the conductor pattern 31 to generate heat. An infrared camera 12 is moved in a direction perpendicular to the conductor patterns 31, to thereby detect a heat-generating conductor pattern 31. Then, the infrared camera 31 is moved along the heat-generating conductor pattern 31, to thereby detect a heat-generating spot of a part out of a straight line, and the position is stored as a short circuit spot. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a defect inspection method and a defect inspection apparatus for a conductor pattern suitable for detecting a defect such as a short circuit or disconnection of wiring of a cholesteric liquid crystal display device.

  When manufacturing a cholesteric liquid crystal display device, a large number of wirings and electrodes made of a light-transmitting conductive material such as ITO (Indium-Tin Oxide) on a substrate such as glass (hereinafter, these wirings and electrodes etc. After the formation of “conductor patterns”, an electrical inspection is performed to detect the presence or absence of defects such as short circuits or disconnections of these conductor patterns.

  Generally, in the electrical inspection, probe pins are brought into contact with the end portions of each conductor pattern, and the electrical resistance at both ends of one conductor pattern, and the electrical resistance and capacitance between adjacent conductor patterns. It is done by measuring. Although it is relatively easy to detect the presence or absence of a defect by this electrical inspection, it is necessary to specify the defect location in order to repair the defect.

  There are two methods for identifying a defect location: a method in which an operator observes a substrate using a magnifying glass (microscope), and a method in which the substrate is photographed with a camera and image processing is performed to automatically detect the defect location. . The former method has a problem that the load on the worker is large and the detection efficiency and detection accuracy differ greatly depending on the worker.

  In the latter method, the load on the worker is small and the work can be performed efficiently. However, since a conductor pattern made of a light-transmitting conductive material transmits light, the contrast of an image photographed by a camera is low, and detection errors are likely to occur. Although it is conceivable to use a high-resolution optical system in order to reduce detection errors, there is a problem in that this increases the cost of the inspection apparatus and increases the time required for image processing. In addition, when a foreign substance or the like that blocks light adheres to the substrate, there is a problem that the contrast changes greatly and it becomes difficult to detect a defect in the transparent conductor pattern.

Patent Documents 1 to 3 propose that a voltage is applied to a conductor pattern to cause resistance heat generation, and a substrate is photographed with an infrared camera to detect a defective portion. In such a method, an image having a large contrast difference between a portion that generates resistance (a portion that is energized) and a portion that does not (the portion that is not energized) is obtained. There is an advantage that it is easy to specify the location.
JP-A-1-185454 JP-A-5-340905 JP-A-6-51011

  However, the present inventors consider that the techniques described in Patent Documents 1 to 3 described above have the following problems. That is, all the methods described in Patent Documents 1 to 3 capture the entire image of the substrate. In order to capture the entire image of the substrate, for example, a high-resolution infrared camera may be arranged at a position away from the substrate, and the entire image of the substrate may be taken at once by this infrared camera. However, in this case, a high-resolution infrared camera and a high-performance image processing apparatus corresponding to the high-resolution infrared camera are required, which increases the cost of the inspection apparatus.

  It is also conceivable to arrange a relatively low-resolution infrared camera near the substrate and move (scan) the infrared camera relative to the substrate to obtain an entire image of the substrate. However, in this case, it takes time to acquire the entire image of the substrate, and the throughput is reduced.

  As described above, an object of the present invention is to provide a conductor pattern defect inspection method and a defect inspection apparatus capable of detecting a defective portion of a transparent conductor pattern in a short time without obtaining an image of the entire substrate. .

  According to one aspect of the present invention, in a defect inspection method for a conductor pattern for inspecting a plurality of conductor pattern defects formed on a substrate, a first step of applying a voltage to the plurality of conductor patterns; There is provided a conductor pattern defect inspection method comprising a second step of examining whether or not the conductor pattern is generating heat by moving an infrared detector in a direction crossing the plurality of conductor patterns.

  According to another aspect of the present invention, a stage on which a substrate on which a plurality of conductor patterns are formed is placed, an infrared detector disposed above the stage, the infrared detector, and the substrate. A first moving mechanism for moving at least one of the infrared detector and the substrate in a first direction parallel to the surface of the substrate; and at least one of the infrared detector and the substrate parallel to the surface of the substrate and the first direction The conductor pattern generates heat based on a second moving mechanism that moves in a second direction that intersects the voltage, a voltage applying unit that applies a voltage to the conductor pattern, and a signal output from the infrared detector. A main control unit that determines whether or not the voltage is applied to the plurality of conductor patterns by controlling the voltage application unit, and the first moving mechanism and the first control unit To control the two movement mechanisms Provided is a conductor pattern defect inspection device that detects the conductor pattern that generates heat based on the output of the infrared detector by moving the infrared detector relative to the direction intersecting the plurality of conductor patterns. Is done.

  In the present invention, for example, during a short circuit inspection, a voltage is applied between adjacent conductor patterns. When there is no short circuit defect between these conductor patterns, no current flows between these conductor patterns, and the conductor patterns do not generate heat. On the other hand, when there is a short-circuit defect between these conductor patterns, current flows through the conductor pattern, Joule heat is generated, and the conductor pattern generates heat. By performing signal processing (image processing) on the output of the infrared detector while moving the infrared detector in a direction crossing the conductor pattern, a heat generating conductor pattern (that is, a conductor pattern having a short-circuit defect) and A conductor pattern that does not generate heat (that is, a conductor pattern having no short-circuit defect) can be distinguished.

  When a conductor pattern having a short-circuit portion is detected, the infrared detector is moved along the conductor pattern, and a heat generation portion deviating from a criterion based on the design data of the conductor pattern is detected. For example, in the case of a linear conductor pattern, when a heat generation location deviating from the straight line is detected, the heat generation location is set as a short-circuit location. In this way, in the present invention, the defective portion is detected.

  In the present invention, instead of acquiring the entire image of the substrate, the infrared detector is moved in the direction intersecting the conductor pattern to detect the heat generating conductor pattern, and based on the result. Determine if there is a defect. This eliminates the need for a high-resolution infrared camera or a high-performance image processing apparatus for processing a high-resolution image, thereby reducing the apparatus cost and reducing the time required for the inspection.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a schematic view showing the configuration of a conductor pattern defect inspection apparatus according to the first embodiment of the present invention. In the present embodiment, an example in which the present invention is applied to defect detection of a conductor pattern of a substrate for a cholesteric liquid crystal display device will be described.

  The cholesteric liquid crystal display device is a reflective display device having a structure in which cholesteric liquid crystal is sealed between a pair of transparent substrates and a light absorption layer is disposed on the back surface. A plurality of transparent conductor patterns extending in the horizontal direction (X-axis direction) are formed on one transparent substrate, and a plurality of transparent conductor patterns extending in the vertical direction (Y-axis direction) are formed on the other transparent substrate. Yes. The portions where the transparent conductor pattern formed on one substrate intersects the transparent conductor pattern formed on the other substrate are pixels. The cholesteric liquid crystal changes to a focal conic state in which light is transmitted or a planar state in which light having a specific wavelength is reflected according to an applied voltage, and maintains the state immediately before the application of voltage is stopped. Therefore, it is possible to display a character or an image without supplying voltage and to realize a display device with extremely low power consumption. In addition, a liquid crystal panel that reflects red light, a liquid crystal panel that reflects green light, and a liquid crystal panel that reflects blue light can be overlapped to form a full-color display device.

  As shown in FIG. 1, the conductor pattern defect inspection apparatus according to this embodiment includes a stage 11, an infrared camera (infrared detector) 12, an X-axis guide rail 13, a Y-axis guide rail 14, probes 15a and 15b, The main control unit 16, the X-axis drive control unit 17, the Y-axis drive control unit 18, the voltage application unit 19, the probe drive unit 20, the design data storage unit 21, and the defect location storage unit 22 are configured.

  The substrate 30 to be inspected is placed on the stage 11. Here, as shown in FIG. 1, a large number of linear conductor patterns 31 made of a transparent conductor material such as ITO are formed on the surface of the substrate 30 in parallel to the X-axis direction (lateral direction) and in the Y-axis direction. It is assumed that they are arranged in the (vertical direction) at regular intervals.

  The infrared camera 12 is disposed above the substrate 30. The infrared camera 12 is supported by an X-axis guide rail 13 so as to be movable in the X-axis direction. The X-axis guide rail 13 is supported by the Y-axis guide rail 14 so as to be movable in the Y-axis direction. The positions of the infrared camera 12 in the X-axis direction and the Y-axis direction are controlled by the main control unit 16 via the X-axis drive control unit 17 and the Y-axis drive control unit 18. The X-axis drive control unit 17 and the Y-axis drive control unit 18 are provided with encoders (not shown) that detect the position of the infrared camera 12 in the X-axis direction and the Y-axis direction, respectively. The unit 16 can know the position (X coordinate and Y coordinate) of the infrared camera 12 from the output of these encoders.

  The probes 15a and 15b are provided with a plurality of probe pins (not shown) on the lower side thereof. The probe 15 a is driven by the probe driving unit 20, and a probe pin is brought into contact with the left end portion of the conductor pattern 31. In addition, the probe 15 b is driven by the probe driving unit 20 to bring a probe pin into contact with the right end of the conductor pattern 31.

  The voltage application unit 19 supplies a predetermined voltage to the predetermined conductor pattern 31 via the probes 15a and 15b based on a signal from the main control unit 16.

  The design data storage unit 21 stores design data for the conductor pattern 31. The main control unit 16 extracts the regularity of the conductor pattern 31 to be inspected from the design data stored in the design data storage unit 21. The regularity of the conductor pattern is data indicating an outline of the shape of the conductor pattern, and is used for determining the presence or absence of a defect. For example, in this embodiment, since all the conductor patterns 31 are straight lines parallel to the X axis, the main controller 16 has a regularity between the conductor patterns 31 so that the start point and the end point of the conductor patterns 31 are continuous. It is determined that there is no defect and that there is no sudden change in the X coordinate.

  The main control unit 16 controls the X-axis drive control unit 17, the Y-axis drive control unit 18, the voltage application unit 19, and the probe drive unit 20, and inputs a signal output from the infrared camera 12 to perform image processing. . Then, the presence / absence of a defect is determined based on the regularity of the conductor pattern described above, and when it is determined that there is a defect, the position of the X coordinate and the Y coordinate of the infrared camera 12 at that time is stored as a defect location. Store in unit 22.

  Hereinafter, the defect inspection method for the conductor pattern according to the present embodiment will be described with reference to the flowchart shown in FIG. 2 and the schematic diagrams shown in FIGS. Here, the operation when a short-circuit defect is detected will be described. Here, it is assumed that a short-circuit defect has occurred in a portion surrounded by a broken-line circle in FIGS.

  When detecting a short-circuit defect, in step S11, the main control unit 16 controls the probe driving unit 20 to connect the probe pin of the probe 15a to the left end portion of the odd-numbered conductor pattern 31 as shown in FIG. The probe pin of the probe 15 b is connected to the right end portion of the even-numbered conductor pattern 31. In step S12, the voltage application unit 19 is controlled to supply a predetermined voltage between the probes 15a and 15b. The voltage supplied between the probes 15a and 15b may be a DC voltage or an AC voltage. Further, an alternating voltage of a triangular wave or a rectangular wave may be used.

  When there is no short circuit defect, the odd-numbered conductor pattern 31 and the even-numbered conductor pattern 31 are not connected, and thus the conductor pattern 31 does not generate heat. However, when there is a short-circuit defect as shown in FIGS. 3 and 4, current flows as shown by a thick line in FIG. 4 to generate Joule heat, and the temperature of the conductor pattern 31 in the portion where the current flows is To rise.

  After a predetermined voltage is applied between the probes 15a and 15b and a time required for the temperature of the shorted conductor pattern 31 to sufficiently rise has elapsed, the process proceeds to step S13. Then, the main control unit 16 controls the X-axis drive control unit 17 and the Y-axis drive control unit 18 to make the infrared camera 12 of the conductor pattern 31 in the first row (uppermost part) as shown in FIG. Move to the upper right corner. Thereafter, the process proceeds to step S14, where the main control unit 16 controls the Y-axis drive control unit 18 to move the infrared camera 12 in the + Y direction (from top to bottom) at a constant speed as indicated by the arrow A in FIG. On the other hand, the image captured by the infrared camera 12 is subjected to image processing to determine the presence or absence of the conductor pattern 31 that generates heat (emits a certain amount or more of infrared rays). When the heat generating conductive pattern 31 is detected, the position (Y coordinate) is stored.

  When the infrared camera 12 passes through the conductor pattern 31 in the last row (lowermost part), the process proceeds to step S15, and the main control unit 16 determines whether or not there is a conductor pattern 31 that generates heat. Here, if it is determined that there is no heat-generating conductor pattern 31 (in the case of NO), the short-circuit inspection is terminated assuming that there is no short-circuit defect.

  On the other hand, when it is determined in step S15 that there is a conductor pattern 31 that generates heat (in the case of YES), the process proceeds to step S16. The main control unit 16 controls the Y-axis drive control unit 18 to move the infrared camera 12 to the right end position of the conductor pattern 31 that is generating heat.

  Thereafter, the process proceeds to step S17, where the main control unit 16 controls the X-axis drive control unit 17, and moves the infrared camera 12 to the left (X-axis direction) along the heat-generating conductor pattern 31 as shown in FIG. ). Further, the main control unit 16 performs image processing on an image photographed by the infrared camera 12, and based on the result, Y-axis drive control is performed so that the heat-generating conductor pattern 31 is located at the center of the visual field of the infrared camera 12. The unit 18 is controlled to adjust the position of the infrared camera 12. The main control unit 16 monitors the X and Y coordinates of the infrared camera 12 acquired from the X-axis drive control unit 17 and the Y-axis drive control unit 18, and the movement of the infrared camera 12 is the regularity of the conductor pattern. It is determined whether or not it conforms to.

  If it conforms to the regularity of the conductor pattern, that is, a portion where the movement of the infrared camera 12 is linear is determined not to be a defective portion. On the other hand, when the regularity of the conductor pattern deviates, that is, when the infrared camera 12 moves suddenly in the Y-axis direction, the location is determined as a defective portion. In step S18, the position (X coordinate and Y coordinate) of the infrared camera 12 at that time is stored in the defect location storage unit 22 as the position of the defect location.

  In this way, the presence / absence of a short-circuit defect is automatically inspected, and when it is determined that there is a short-circuit defect, the position (X coordinate and Y coordinate) of the defective part is stored in the defective part storage unit 22. If there are a plurality of conductor patterns 31 that generate heat, the processes from step S16 to step S18 are performed for each conductor pattern 31. In addition, the short-circuit defect is repaired by cutting the short-circuit portion with a laser in a repair process after the short-circuit inspection process, for example.

  In the present embodiment, as described above, the infrared camera (infrared detector) 12 is moved in a direction intersecting the conductor pattern 31 (+ Y direction in the above example) while a voltage is applied to each conductor pattern 31. Then, the conductor pattern in which the short-circuit defect has occurred is detected, and then the infrared camera 12 is moved along the conductor pattern 31 in which the short-circuit has occurred to identify the short-circuit portion. Therefore, it is not necessary to acquire the entire image of the substrate as in the prior art, and the time required for the short circuit inspection is shortened. Further, since the infrared camera 12 only shoots a part of the substrate 30, it may have a relatively low resolution, and there is an advantage that the apparatus cost can be reduced.

  Furthermore, in the present embodiment, the short-circuit portion is specified not by the calorific value, but by the deviation from the regularity of the conductor pattern, so that the area of the short-circuit portion is large and the calorific value is small. However, it is easy to identify the short-circuit point.

  Next, the operation at the time of inspection for the presence or absence of a disconnection defect will be described with reference to the schematic diagram shown in FIG. 6 and the flowchart shown in FIG. Here, it is assumed that a disconnection defect occurs in a portion surrounded by a broken-line circle in FIG.

  When detecting a disconnection defect, in step S21, the main control unit 16 controls the probe driving unit 20 to connect the probe pin of the probe 15a to the left end of each conductor pattern 31 as shown in FIG. The probe pin 15b is connected to the right end of each conductor pattern 31. In step S22, the voltage application unit 19 is controlled to apply a predetermined voltage between the probes 15a and 15b.

  When there is no disconnection defect, current flows through the conductor pattern 31 and Joule heat is generated. However, when there is a disconnection defect as shown in FIG. 6, no current flows through the conductor pattern 31, so the conductor pattern 31 does not generate heat.

  After a predetermined voltage is applied between the probes 15a and 15b and a time required for the temperature of the conductor pattern 31 to sufficiently rise has elapsed, the process proceeds to step S23. Then, the main control unit 16 controls the X-axis drive control unit 17 and the Y-axis drive control unit 18 so that the infrared camera 12 is placed at the right end of the conductor pattern 31 in the first row (uppermost part) as shown in FIG. Move to the top. Thereafter, the process proceeds to step S24, where the main control unit 16 controls the Y-axis drive control unit 18 to move the infrared camera 12 in the + Y direction (from top to bottom) at a constant speed as indicated by arrow A in FIG. Thus, the conductor pattern 31 that does not generate heat (the amount of emitted infrared rays is small) is detected. When the conductor pattern 31 that does not generate heat is detected, the position (Y coordinate) is stored.

  When the infrared camera 12 passes the conductor pattern 31 in the last row, the process proceeds to step S25, and the main control unit 16 controls the X-axis drive control unit 17 to make the infrared camera 12 the left end of the conductor pattern 31 in the last row. Move to the bottom. Thereafter, the process proceeds to step S26, and the main control unit 16 controls the Y-axis drive control unit 18 to move the infrared camera 12 at a constant speed in the -Y direction (from bottom to top) as indicated by the broken line arrow B in FIG. To detect the conductor pattern 31 not generating heat.

  Next, the process proceeds to step S <b> 27, and the main control unit 16 stores the position of the conductor pattern 31 that is not generating heat (disconnected) in the defect location storage unit 22. In this manner, the conductor pattern inspection apparatus according to the present embodiment can automatically detect the conductor pattern 31 in which a disconnection has occurred.

  As described above, according to the present embodiment, it is not necessary to acquire the entire image of the substrate 30 even in the case of the disconnection inspection, and an expensive high-resolution infrared camera is unnecessary, and the time required for the inspection is shortened. There is an advantage.

(Second Embodiment)
FIG. 8 is a schematic diagram showing a configuration of a conductor pattern defect inspection apparatus according to the second embodiment of the present invention. This embodiment is different from the first embodiment in that a laser device for repairing a short-circuit defect is provided, and other configurations are basically the same as those of the first embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the present embodiment, a laser device 41 for short-circuit defect repair is supported on the X-axis guide rail 13 together with the infrared camera 12. The infrared camera 12 and the laser device 41 move integrally along the X-axis guide rail 13. The interval (offset amount Δx) between the infrared camera 12 and the laser device 41 is stored in the main control unit 16.

  Hereinafter, the operation at the time of short-circuit defect inspection using the defect inspection apparatus of the present embodiment will be described. Again, reference is made to FIGS.

  First, as in the first embodiment, the main control unit 16 controls the probe driving unit 20 to bring the probe pin of the probe 15a into contact with the left end portion of the odd-numbered conductor pattern 31 so as to contact the even-numbered conductor. The probe pin of the probe 15 b is brought into contact with the right end portion of the pattern 31. Thereafter, the main control unit 16 controls the voltage application unit 19 to apply a predetermined voltage between the probes 15a and 15b.

  Next, the main control unit 16 controls the X-axis drive control unit 17 and the Y-axis drive control unit 18, and arranges the infrared camera 12 at the upper right end of the conductor pattern 31 in the first row (top), Thereafter, the infrared camera 12 is moved in the + Y direction (from top to bottom). At this time, the main control unit 16 performs image processing on the image captured by the infrared camera 12 and determines the presence or absence of the conductive pattern 31 that generates heat. When the heat generating conductor pattern 31 is detected, the position is stored.

  After the infrared camera 12 passes over the conductor pattern 31 in the last row (lowermost part), the main control unit 16 determines whether or not there is a conductor pattern that generates heat. Here, when it is determined that there is no heat-generating conductor pattern, the short-circuit inspection is terminated assuming that there is no short-circuit defect.

  On the other hand, when it is determined that there is a conductor pattern 31 that generates heat, the main control unit 16 moves the infrared camera 12 to the right end position of the conductor pattern 31 that generates heat. Thereafter, as shown in FIG. 9A, the main control unit 16 performs image processing on the image captured by the infrared camera 12 while moving the infrared camera 12 to the left along the conductive pattern 31 that generates heat. Thus, a location deviating from the regularity of the conductor pattern, that is, a short-circuit location is detected. And when a short circuit location is detected, the position is memorize | stored in the defect location memory | storage part 22. FIG. The steps up to here are basically the same as those in the first embodiment.

  Next, the main control unit 16 moves the infrared camera 12 and the laser device 41 by the offset Δx, and arranges the laser device 41 above the short-circuit portion. And as shown in FIG.9 (b), the laser apparatus 41 is driven and a short circuit location is cut | disconnected. In this case, since the laser device is generally provided with an optical microscope for confirming the laser irradiation position, the main control unit 16 converts the image of the optical microscope provided in the laser device into a charge-coupled device (CCD). ) And the like, and processing such as determination of the cutting location and optimization of the focal length of the laser device is performed based on the image.

  Thus, according to the defect inspection apparatus of the present embodiment, the detection and repair of the short-circuited portion of the conductor pattern 31 is automatically performed. Note that it is preferable that the substrate on which the defect has been repaired is subjected to defect inspection again to confirm that the defect has been removed.

  In both the first and second embodiments described above, the infrared camera 12 is moved in the order indicated by the numbers in parentheses in FIG. That is, the infrared camera 12 is moved in the Y-axis direction to the top of the conductive pattern 31 in the last row to detect the conductive pattern 31 that generates heat, and then the infrared camera 12 moves along the conductive pattern 31 that generates heat. The short-circuit portion of each conductor pattern 31 is specified by moving in the X-axis direction. However, the infrared camera 12 may be moved in the order indicated by the numbers in parentheses in FIG. That is, when the infrared camera 12 is moved in the Y-axis direction to detect the heat-generating conductor pattern 31, the infrared camera 12 is moved in the X-axis direction along the conductor pattern 31 to identify the short-circuited portion. Thereafter, the infrared camera 12 may be moved in the X-axis direction to the end of the conductor pattern 31 and then moved in the Y-axis direction to search for the next heat-generating conductor pattern 31.

  In both the first and second embodiments, the infrared camera 12 is moved in the X-axis direction and the Y-axis direction. For example, the infrared camera 12 is moved in the X-axis direction and the substrate 30 is placed. The stage 11 to be moved may move in the Y-axis direction, the infrared camera 12 may be fixed, and the stage 11 may move in the X-axis direction and the Y-axis direction.

  Hereinafter, an example in which a defect is detected and a short-circuit portion is repaired by the above-described method according to the present invention will be described in comparison with a comparative example.

  As a test body, a substrate having five short-circuited portions per sheet was prepared. The size of one substrate is 300 mm × 250 mm. On the substrate, 1024 linear conductor patterns (wirings) made of ITO are arranged at a pitch of 240 μm. Each conductor pattern has a length of 200 mm, and an interval (gap) between the conductor patterns is 15 μm.

(Comparative Example 1)
The board | substrate of the said test body was electrically test | inspected and the conductor pattern in which the short circuit has generate | occur | produced was specified. Thereafter, the operator inspected the conductor pattern using a magnifying glass (microscope), and identified the short-circuited portion. Next, the operator operated the laser device that generates the second harmonic of YAG to cut the short-circuited portion, and then performed electrical inspection again to confirm that the short-circuited portion was repaired.

  In Comparative Example 1, it took about 5 minutes for the electrical inspection per substrate of the test specimen, and it took about 10 minutes to identify the short-circuited part and repair the short-circuited part by the laser device.

(Comparative Example 2)
A short-circuit portion of the conductive pattern of the substrate of the specimen was automatically detected using a conventional inspection apparatus. That is, a camera (not an infrared camera) was scanned to capture an entire image of the substrate of the test specimen, and then the captured image was subjected to image processing to identify a short-circuit location. Since this inspection apparatus also detects foreign matter adhering to the substrate in the same manner as the short-circuited portion, the operator uses a microscope to check the short-circuited portion, and a laser that generates YAG second harmonics at the location confirmed as short-circuited. Disconnected using the device. Next, an electrical inspection was performed to confirm that the short-circuit portion was repaired.

  In Comparative Example 2, it took about 5 minutes for the electrical inspection per substrate of the test specimen, and it took about 2 minutes for the confirmation of the short-circuited part and the repair of the short-circuited part by the laser device.

Example 1
The short-circuit part of the board | substrate of a test body was specified by the defect inspection apparatus demonstrated in 1st Embodiment. A rectangular wave alternating voltage having a frequency of 100 Hz and an amplitude of 100 V was applied to the conductor pattern. Five seconds after the voltage was applied, the infrared camera was moved in the Y-axis direction to detect a heat generating conductor pattern. When a conductive pattern that generated heat was detected, the portion was marked. This operation took about 5 seconds.

  Next, the infrared camera was moved along the marked conductor pattern, and a portion deviating from the regularity of the conductor pattern, that is, a short-circuit portion was detected, and the portion was marked. It took about 5 seconds for each conductor pattern to detect this short-circuited portion.

  Next, the laser device arranged separately from the infrared camera was moved to the short-circuit portion, and the short-circuit portion was cut by irradiating the laser beam. The movement of the laser device and the disconnection of the short-circuit portion took about 5 seconds for each short-circuit portion. Next, a voltage is applied between the odd-numbered conductor pattern and the even-numbered conductor pattern, and the infrared camera is moved in the Y-axis direction. Confirmed that it was repaired. In Example 1, the processing time per substrate of the test specimen was about 1 minute.

(Example 2)
The apparatus described in the second embodiment was used, and the infrared camera and the laser apparatus were moved as shown in FIG. After correcting the short-circuit portion, a voltage is applied between the odd-numbered conductor pattern and the even-numbered conductor pattern, and the infrared camera is moved in the Y-axis direction so that there is no heat-generating conductor pattern. That is, it was confirmed that the short-circuit portion was repaired. In Example 2, the processing time per substrate of the test specimen was about 0.5 minutes.

(Example 3)
The apparatus described in the second embodiment was used, and the infrared camera and the laser apparatus were moved as shown in FIG. A voltage was applied to the conductor pattern every time the short-circuit portion was corrected, and it was confirmed that the conductor pattern did not generate heat, that is, the short-circuit portion was repaired. In Example 3, the processing time per substrate of the test specimen was about 0.5 minutes.

  From the comparison of Examples 1 to 3 and Comparative Examples 1 and 2, it was confirmed that the present invention shortens the time required for detection and repair of short-circuit defects in the conductor pattern.

FIG. 1 is a schematic view showing the configuration of a conductor pattern defect inspection apparatus according to the first embodiment of the present invention. FIG. 2 is a flowchart showing a conductor pattern defect inspection method (at the time of short-circuit defect inspection) according to the embodiment. Drawing 3 is a mimetic diagram (the 1) showing a defect inspection method (at the time of a short circuit defect inspection) of a conductor pattern concerning an embodiment. Drawing 4 is a mimetic diagram (the 2) showing a defect inspection method (at the time of short circuit defect inspection) of a conductor pattern concerning an embodiment. FIG. 5 is a schematic diagram (No. 3) showing the conductor pattern defect inspection method (at the time of short-circuit defect inspection) according to the embodiment. FIG. 6 is a schematic diagram showing a conductor pattern defect inspection method (when a disconnection defect is inspected) according to the embodiment. FIG. 7 is a flowchart showing a conductor pattern defect inspection method (at the time of disconnection defect inspection) according to the embodiment. FIG. 8 is a schematic diagram showing a configuration of a conductor pattern defect inspection apparatus according to the second embodiment of the present invention. 9A and 9B are schematic views showing a method for repairing a short-circuit defect. FIGS. 10A and 10B are schematic diagrams showing a moving method of the infrared camera.

Explanation of symbols

11 ... stage,
12 ... Infrared camera,
13 ... X-axis guide rail,
14 ... Y-axis guide rail,
15a, 15b ... probes,
16 ... main control part,
17 ... X-axis drive control unit,
18 ... Y-axis drive control unit,
19: Voltage application unit,
20: Probe drive unit,
21 ... design data storage unit,
22 ... Defect location storage unit,
30 ... substrate,
31 ... Conductor pattern,
41 ... Laser device.

Claims (6)

In a defect inspection method for a conductor pattern for inspecting a plurality of conductor pattern defects formed on a substrate,
A first step of applying a voltage to the plurality of conductor patterns;
And a second step of examining whether or not the conductor pattern is generating heat by moving an infrared detector in a direction crossing the plurality of conductor patterns. .   The infrared detector is moved along the heat-generating conductor pattern detected in the second step, and a heat generation point that deviates from a criterion based on the design data of the conductor pattern is detected as a short-circuit point. The method for inspecting a defect of a conductor pattern according to claim 1, further comprising a step.   The conductor pattern defect inspection method according to claim 2, further comprising a fourth step of repairing the short circuit by irradiating the short circuit portion with laser light after the third step.   The defect inspection method for a conductor pattern according to any one of claims 1 to 3, wherein the substrate is a substrate for a cholesteric liquid crystal display device. A stage on which a substrate on which a plurality of conductor patterns are formed is placed;
An infrared detector disposed above the stage;
A first moving mechanism for moving at least one of the infrared detector and the substrate in a first direction parallel to the surface of the substrate;
A second moving mechanism for moving at least one of the infrared detector and the substrate in a second direction parallel to the surface of the substrate and intersecting the first direction;
A voltage application unit for applying a voltage to the conductor pattern;
A main controller that determines whether or not the conductor pattern is generating heat based on a signal output from the infrared detector;
The main control unit controls the voltage applying unit to apply a voltage to the plurality of conductor patterns, and controls the first moving mechanism and the second moving mechanism to control the plurality of infrared detectors. A defect inspection apparatus for a conductor pattern, wherein the conductor pattern is moved relatively in a direction intersecting with the conductor pattern, and a conductor pattern that generates heat is detected based on an output of the infrared detector.   6. The defect inspection apparatus for a conductor pattern according to claim 5, further comprising a laser device for cutting a short-circuit portion of the conductor pattern.

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