WO2013145839A1

WO2013145839A1 - Defect detection apparatus

Info

Publication number: WO2013145839A1
Application number: PCT/JP2013/051964
Authority: WO
Inventors: 泰広上田; 敏幸篠崎; 森田　春雪; 英斗纐纈; 行彦中倉
Original assignee: シャープ株式会社
Priority date: 2012-03-28
Filing date: 2013-01-30
Publication date: 2013-10-03
Also published as: JP2013205234A

Abstract

To suitably detect defects of wiring on a substrate. An infrared camera (4) is attached to the beam section (12c) of a gantry (12), said beam section being disposed across an alignment stage (11) having a mother board (1) placed thereon, such that the relative position with respect to the board surface of the mother board (1) placed on the alignment stage (11) is fixed in the direction perpendicular to the board surface.

Description

Defect detection device

The present invention relates to a defect detection apparatus for detecting defects such as wiring formed on a substrate.

Conventionally, in a manufacturing process of a liquid crystal panel or the like, after a semiconductor element such as a TFT (thin film transistor), a wiring, or the like is formed on a transparent substrate, an array inspection for inspecting the presence or absence of a short circuit of the semiconductor element or the wiring is performed.

Usually, in the array inspection, a probe is brought into contact with an end portion of a wiring, and the presence or absence of a short circuit is inspected by performing a continuity test for measuring the electric resistance at both ends of the wiring or the electric resistance and capacitance between adjacent wirings. For example, Patent Document 1 discloses an inspection apparatus including a probe unit that supplies current to an electrode and a sensor unit that detects the current supplied to the wiring and determines the presence or absence of a defect.

However, even if such a continuity test alone can detect the presence or absence of a defect such as a wiring, the position of the defect may not be specified, and a technique for specifying not only the presence or absence of a defect but also the position of the defect Is required.

As a technique for specifying the position of a defect such as wiring, for example, in Patent Document 2, a two-dimensional image of a substrate is acquired by imaging the substrate with a licensor, and the two-dimensional image is subjected to image processing to obtain a defect position. Is specified.

Patent Documents 3 to 5 disclose techniques for specifying a short-circuit position by passing a current through a wiring or the like to be inspected, photographing with an infrared camera, and detecting heat generation of the wiring or the like.

JP 2007-206641 A (released on August 16, 2007) JP 2010-66236 A (published March 25, 2010) Japanese Patent Laid-Open No. 4-72552 (published March 6, 1992) JP-A-6-207914 (published July 26, 1994) Japanese Patent Laid-Open No. 2-64594 (published on March 5, 1990)

By the way, in the inspection system using the imaging means, the position measurement accuracy varies when the distance between the imaging means and the inspection object changes. That is, when the distance between the imaging unit and the inspection object changes, the area of the area on the substrate that is imaged by the imaging unit changes. On the other hand, the number of pixels of the image sensor in the imaging means is constant. For this reason, when the distance between the imaging means and the inspection object changes, the resolution of the image (the area of the area on the inspection object per pixel) changes, and the position measurement accuracy varies.

For this reason, in the inspection system using the imaging means, it is necessary to detect the resolution of the imaging means and adjust the distance between the imaging means and the inspection object based on the detection result.

However, inspection apparatuses that perform inspection using an infrared camera as disclosed in Patent Documents 3 to 5 have a problem that it is difficult to accurately determine the resolution of the infrared camera.

In other words, since the infrared camera observes only the temperature difference between the imaging objects by detecting the infrared rays radiated from the imaging object, the position and size of the reference object for determining the resolution are known in advance. And a plurality of objects having different temperatures (a plurality of different temperature regions). However, if there is a temperature difference between these objects, the heat of each object moves so as to eliminate the temperature difference, so the boundary of the temperature difference becomes unclear. For this reason, it is difficult to always provide a reference with sufficient accuracy, and it is difficult to always obtain sufficient resolution with the techniques of Patent Documents 3 to 5. Further, even if a reference object with sufficient accuracy can be prepared, it takes time to adjust the distance between the imaging means and the inspection object, resulting in a problem that inspection efficiency is lowered.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a defect detection apparatus that can easily and appropriately detect the position of a defect in a wiring formed on a substrate. .

A defect detection apparatus according to the present invention is a defect detection apparatus for detecting a defect of a wiring formed on a substrate, and a voltage application for applying a voltage to a stage on which the substrate is placed and a wiring to be inspected on the substrate. And a gantry arranged so as to straddle the stage, and the inspection in which a voltage is applied by the voltage application unit, disposed at a position facing the substrate surface of the substrate placed on the stage in the gantry. An infrared camera that images the target wiring, and the gantry is movable in the X direction, which is parallel to the substrate surface of the substrate placed on the stage, and the infrared camera is mounted on the stage. It is attached to the gantry so that the relative position with respect to the substrate surface in the Z direction which is a direction perpendicular to the substrate surface of the substrate to be placed is constant. It is characterized by a door.

According to the above configuration, it is possible to easily detect a defective portion by imaging the inspection target wiring in a state where a voltage is applied with an infrared camera. In addition, by making the position in the direction perpendicular to the substrate surface of the infrared camera constant, it is difficult to detect the resolution and adjust the distance to the inspection object compared to a camera that captures an image in the visible light wavelength region. Regardless of the configuration used, variations in position measurement accuracy can be suppressed. Further, since the gantry can be translated in a direction parallel to the substrate surface, the infrared camera can be easily moved to a position corresponding to the inspection target wiring on the substrate. That is, the infrared camera can be translated along a direction parallel to the substrate surface while keeping the position in the direction perpendicular to the substrate surface of the infrared camera constant, and can be moved to a position corresponding to the inspection target location on the substrate. . Thereby, the defect of the inspection object location in a board | substrate can be detected with high precision.

The infrared camera is attached to the gantry so as to be parallel to the substrate surface of the substrate placed on the stage and parallel to the Y direction that intersects the X direction. Also good.

According to the above configuration, while keeping the position in the direction perpendicular to the substrate surface of the infrared camera constant, the infrared camera is translated along the X and Y directions parallel to the substrate surface, so It can be moved to a corresponding position. Thereby, the defect of the inspection object location in a board | substrate can be detected with high precision.

The voltage application unit includes a probe unit including a probe needle that contacts a connection terminal provided on the substrate, and the probe unit includes a substrate on which the probe needle is placed on the stage. It is good also as a structure provided so that the movement to the position which contacts the said connection terminal, and the position spaced apart with respect to the said connection terminal is possible.

According to the above configuration, the inspection voltage can be easily applied to the wiring to be inspected by bringing the probe needle into contact with the connection terminal provided on the substrate to be inspected.

One or a plurality of substrate circuits are formed on the substrate, the connection terminal is provided at an outer edge portion of each substrate circuit, and the probe portion has a shape of an outer edge portion of each substrate circuit. When the probe needle of the probe section moves to a position in contact with the connection terminal of the board circuit to be inspected among the board circuits, the board circuit is provided. It is good also as a structure exposed through the said opening part.

According to the above configuration, since the substrate circuit is exposed through the opening, it is possible to easily image the inspection target wiring with the infrared camera in a state where a voltage is applied to the inspection target wiring of the substrate circuit. it can.

The substrate circuit is a substrate circuit provided in a display panel, and includes a pixel region in which a large number of pixel circuits are arranged, and a peripheral circuit region having a peripheral circuit for driving the pixel circuits. When the probe unit is moved to a position where the probe needle of the probe unit contacts the connection terminal of the substrate circuit to be inspected, the entire pixel region and the peripheral circuit region are passed through the opening. It may be configured to be exposed.

According to the above configuration, defects can be detected in both the pixel region and the peripheral circuit region.

In the infrared camera, the probe section of the probe section is moved to a position where the probe needle of the probe section is in contact with the connection terminal of the substrate circuit to be inspected. It is good also as a structure which can image.

According to the above configuration, since the entire area of the substrate circuit exposed through the opening can be imaged in a single imaging process, the defect detection process can be performed compared to the case where the entire area of the substrate circuit is imaged in multiple steps. The required processing time can be shortened.

As described above, according to the defect detection apparatus of the present invention, it is possible to detect a defect at a location to be inspected on a substrate with high accuracy.

It is the perspective view which showed typically the structure of the defect detection apparatus concerning one Embodiment of this invention. (A) is explanatory drawing which shows the structure of the board | substrate used as the inspection object of the defect detection process using the defect detection apparatus shown in FIG. 1, (b) is the probe part with which the defect detection apparatus shown in FIG. 1 is equipped. It is explanatory drawing which shows this structure. It is a block diagram which shows schematic structure of the defect detection apparatus shown in FIG. It is a flowchart which shows the flow of the defect detection process in the defect detection apparatus shown in FIG. (A)-(c) is explanatory drawing which shows the example of the defect which may arise in the board | substrate shown to Fig.2 (a). (A) is explanatory drawing which shows the structure of the board | substrate used as the test object of the defect detection process using the defect detection apparatus shown in FIG. 1, (b) imaged the board | substrate shown to (a) with the infrared camera. It is explanatory drawing which shows a result, (c) is explanatory drawing which shows the result of having expanded the board | substrate shown to (a) with the optical microscope.

An embodiment of the present invention will be described.

(1-1. Hardware Configuration of Defect Detection Device 100)
FIG. 1 is a perspective view schematically showing a configuration of a defect detection apparatus 100 according to the present embodiment. As shown in this figure, the defect detection apparatus 100 includes a base 10, an alignment stage 11, a gantry 12, mount

parts

15 a and 15 b, a probe part (voltage application part) 3, and an infrared camera 4.

An alignment stage (stage) 11 is installed on the base 10, and a mother substrate (substrate) 1 that is an inspection object is placed on the alignment stage 11. Further, the X-axis direction (the mother substrate 1 in the alignment stage 11) is positioned at both sides of the alignment stage 11 in the base 10 in the Y-axis direction (the direction parallel to the mounting surface of the mother substrate 1 in the alignment stage 11).

Guide rails

13a and 13b extending in a direction parallel to the mounting surface and in a direction intersecting with the Y-axis direction are provided.

The alignment stage 11 is provided with a position adjusting means (not shown). By this position adjusting means, the substrate surface of the mother substrate 1 placed on the alignment stage 11 is parallel to the X axis direction and the Y axis direction. The position is adjusted so that A plurality of TFT substrates (substrate circuits) 2 used for the liquid crystal panel are formed on the mother substrate 1 (in this embodiment, four pieces in the X-axis direction × Y-axis direction on one mother substrate 1). A total of eight TFT substrates 2 arranged in a matrix of two sheets are formed).

The gantry 12 is a gate provided with two

leg portions

12a and 12b arranged so as to face each other across the alignment stage 11, and a beam portion 12c connecting one end sides of the

leg portions

12a and 12b. It has a mold shape. The other end sides of the

leg portions

12a and 12b are attached to guide

rails

13a and 13b provided on the base 10, respectively. As a result, the gantry 12 can be translated in the X-axis direction along the

guide rails

13a and 13b.

Further, a guide rail 14 extending in the Y-axis direction is provided on the beam portion 12c of the gantry 12, and the infrared camera 4 and mount

portions

15a and 15b are attached to the guide rail 14. The infrared camera 4 and the

mounts

15a and 15b are movable in the Y-axis direction along the guide rail 14, while the Z-axis direction (the direction perpendicular to the X-axis direction and the Y-axis direction) is relative to the gantry 12. Is attached to the guide rail 14 so as to be always constant. Therefore, the infrared camera 4 can be translated in the X-axis direction by the movement of the gantry 12, and can be moved in the Y-axis direction along the guide rail 14, while the position in the Z-axis direction is the gantry 12 and alignment stage. 11 is fixed to the gantry 12 in a constant manner. That is, the infrared camera 4 has a gantry so that the distance from the TFT substrate 2 as the inspection object placed on the alignment stage 11 is always constant even when the infrared camera 4 is translated in the X-axis direction and the Y-axis direction. 12 is attached.

The

mount portions

15a and 15b include

guide rails

16a and 16b extending in the Z-axis direction, and probe

support portions

17a and 17b attached to the probe portion 3 are attached to the

guide rails

16a and 16b. . Thereby, the probe part 3 can be translated in the Z-axis direction along the

guide rails

16a and 16b.

FIG. 2A is a plan view of one of the plurality of TFT substrates 2 formed on the mother substrate 1. As shown in this figure, the TFT substrate 2 includes a pixel portion (pixel region, display portion) 21, a peripheral circuit portion (drive circuit portion, peripheral circuit region) 22 provided around the pixel portion 21, and a TFT substrate. Terminal portions 23a to 23d each having a plurality of connection terminals provided on the peripheral edge portion of 2 are provided. In the pixel portion 21, a plurality of scanning lines (gate lines) and a plurality of signal lines (data lines) are provided so as to intersect with each other, and switching elements each including a TFT (thin film transistor, not shown) at each intersection. Is formed. The peripheral circuit section 22 is formed with peripheral circuits for driving the liquid crystal panel, and wirings such as wirings for connecting the respective circuits and auxiliary capacitance wirings (all not shown). Further, the connection terminals of the terminal portions 23a to 23d provided on the peripheral edge portion of the TFT substrate 2 are electrically connected to wirings or circuits provided in the peripheral circuit portion 22 or the pixel portion 21.

FIG. 2B is a plan view of the probe unit 3 for connecting a terminal unit 23a to 23d installed on the TFT substrate 2 and applying a voltage to the wiring and circuit on the TFT 2. FIG.

The probe part 3 has a frame part whose inner edge part has a shape corresponding to the outer edge part of the TFT substrate 2 shown in FIG. That is, the probe portion 3 has a frame portion having an opening inside, and the TFT substrate 2 to be inspected is accommodated in the opening portion of the frame portion.

Further, probe needle portions 24a to 24d having probe needles protruding toward the inner side (opening portion side) are provided on the inner edge portion of the frame portion of the probe portion 3. The probe needles provided in the probe needle portions 24a to 24d are provided at positions corresponding to the connection terminals of the terminal portions 23a to 23d installed on the TFT substrate 2.

As a result, when the probe unit 3 is moved so as to accommodate the TFT substrate 2 to be inspected in the opening of the frame unit, the probe needles provided in the probe needle units 24a to 24d and the terminal units 23a to 23d of the TFT substrate 2 are used. Contact each connection terminal. In the state where the TFT substrate 2 is accommodated in the opening and the probe needles and the connection terminals are connected, the upper portions of the pixel portion 21 and the peripheral circuit portion 22 are exposed without being covered with the probe portion 3.

The probe needles provided in the probe needle parts 24a to 24d are individually connected to a resistance measuring part 37 and a voltage applying part 36, which will be described later, via switching relays (not shown). Thereby, the probe unit 3 can selectively apply a voltage to a desired wiring (one or a plurality of wirings) among the plurality of wirings connected to the terminal units 23a to 23d. The probe unit 3 can measure the resistance value of each wiring connected to the terminal portions 23a to 23d and the resistance value between adjacent wirings.

The infrared camera 4 and the

mounts

15a and 15b are attached to a common guide rail 14 so that the relative positions of these members are constant, and move integrally along the guide rail 14. It has become.

In addition, the infrared camera 4 has the pixel portion 21 of the TFT substrate 2 in the state where the probe needles provided in the probe needle portions 24a to 24d and the connection terminals of the terminal portions 23a to 23d of the TFT substrate 2 are in contact with each other. The entire inspection target region in the peripheral circuit unit 22 is attached to a position where it can be imaged by one imaging process. That is, in the present embodiment, an infrared camera is used as the infrared camera 4, in which the entire area to be inspected is included in the pixel unit 21 and the peripheral circuit unit 22 of the TFT substrate 2 in the imaging range by one imaging process.

However, the present invention is not limited to this, and the infrared camera 4 whose imaging range by one imaging process corresponds to a part of the inspection target area is used, and the infrared camera 4 is in the Y-axis direction with respect to the

mount portions

15a and 15b. It may be configured to be relatively movable in at least one of the X-axis directions, and may be configured to image the inspection target region by a plurality of imaging processes.

In this embodiment, the infrared camera 4 and the

mount portions

15a and 15b are attached to the common guide rail 14. However, the present invention is not limited to this, and the infrared camera 4 and the

mount portions

15a and 15b are attached. Guide rails may be provided individually. In this embodiment, the infrared camera 4 and the

mount parts

15a and 15b are attached to the common gantry 12. However, the present invention is not limited to this, and the gantry for attaching the infrared camera 4 and the

mount parts

15a and 15b. May be provided individually.

(1-2. Configuration of Control System of Defect Detection Device 100)
FIG. 3 is a block diagram schematically showing the functional configuration of the defect detection apparatus 100. As shown in this figure, the defect detection apparatus 100 includes a control unit 31, a data storage unit 32, a gantry moving unit 33, a probe moving unit 34, a camera moving unit 35, a probe unit 3, and an infrared camera 4. The probe unit 3 includes a voltage application unit 36 and a resistance measurement unit 37. The control unit 31 includes a position control unit 41, a voltage control unit 42, a resistance measurement control unit 43, a defect determination unit 44, an imaging control unit 45, and a defect position specifying unit 46.

The gantry moving means 28 is constituted by a motor, a gear or the like (not shown), and translates the gantry 12 in the X-axis direction along the

guide rails

13a and 13b.

The probe moving means 29 is constituted by a motor, a gear or the like (not shown), and moves the

mount portions

15a and 15b along the guide rail 14 provided on the beam portion 12c of the gantry 12 in the Y-axis direction. The

probe support portions

17a and 17b are moved in the Z-axis direction along the

guide rails

16a and 16b provided on the

mount portions

15a and 15b. Thereby, the probe part 3 moves to a Y-axis direction and a Z-axis direction.

The camera moving means 30 is constituted by a motor, a gear or the like (not shown), and moves the infrared camera 4 in the Y-axis direction along the guide rail 14 provided on the beam portion 12c of the gantry 12. When the infrared camera 4 and the

mount parts

15a and 15b are configured to move integrally in the Y-axis direction along the guide rail 14 provided on the beam part 12c of the gantry 12, the camera moving means 30 is used. It may be omitted and the probe moving means 29 may have the function.

The voltage application unit 36 is provided in the probe unit 3, and is individually connected to each probe needle provided in the probe needles 24a to 24d via a switching relay (not shown). Thereby, the voltage application unit 36 can selectively apply a voltage to one or a plurality of desired wirings among the wirings connected to each probe needle.

The resistance measurement unit 37 is provided in the probe unit 3, and is individually connected to each probe needle provided in the probe needles 24a to 24d via a switching relay (not shown). Thereby, the resistance measurement part 37 can measure the resistance value of the desired wiring among the wiring connected to each probe needle, or the resistance value between adjacent wiring.

The control unit 31 is a computer device that includes an arithmetic processing unit such as a CPU and a dedicated processor, and a storage unit (not shown) such as a RAM, a ROM, and an HDD, and is stored in the storage unit. The position control unit 41, the voltage control unit 42, the resistance measurement control unit 43, the defect determination unit 44, the imaging control unit 45, and the defect position specifying unit by reading and executing various information and programs for performing various controls The function 46 is executed to control the operation of each part of the defect detection apparatus 100. The control unit 31 is not limited to being realized using software, and may be configured by hardware logic. In addition, the control unit 31 may be a combination of hardware that performs a part of the processing of the control unit 31 and arithmetic means that executes software that performs control of the hardware or residual processing.

The position controller 41 controls operations of the gantry moving means 33, the probe moving means 34, and the camera moving means 35. That is, the position control unit 41 controls the movement of the gantry 12 in the X-axis direction, the movement of the probe unit 3 and the infrared camera 4 in the Y-axis direction, and the movement of the probe unit 3 in the Z-axis direction.

The voltage control unit 42 controls the operation of the voltage application unit 36 provided in the probe unit 3 to selectively apply a desired voltage to one or more desired wires among the wires connected to each probe needle. To be applied.

The resistance measurement control unit 43 controls the operation of the resistance measurement unit 37 provided in the probe unit 3, and the resistance value of a desired wiring among the wirings connected to each probe needle, or between adjacent wirings Let the resistance value be measured.

The defect determination unit 44 determines the presence or absence of a defect based on the measurement result of the resistance value by the resistance measurement unit 37.

The imaging control unit 45 controls the operation of the infrared camera (thermo viewer) 4 to capture an infrared image (thermo viewer image) of the TFT substrate 2.

The defect position specifying unit 46 specifies the position of the defect based on the measurement result of the resistance value by the resistance measuring unit 37 or the infrared image data captured by the infrared camera 4.

The data storage unit 32 stores various programs used for controlling the defect detection apparatus 100 by the control unit 31, measurement results of wiring or resistance values between the wirings by the resistance measurement unit 37, infrared image data captured by the infrared camera 38, and the like. Remember.

(1-3. Operation of defect detection apparatus 100)
Next, the operation at the time of defect detection processing by the defect detection apparatus 100 will be described with reference to the flowchart shown in FIG.

First, the mother substrate 1 is placed at a predetermined position on the alignment stage 11, and position adjustment (alignment) is performed so that the mother substrate 1 is parallel to the X-axis direction and the Y-axis direction (S1). The mechanism and method for position adjustment are not particularly limited, and conventionally known mechanisms and methods can be used. Further, the position adjustment may be performed automatically or manually.

Next, the position control unit 41 controls the operations of the gantry moving unit 33, the probe moving unit 34, and the camera moving unit 35, and moves the probe unit 3 to a position corresponding to the TFT substrate 2 to be inspected to move the probe unit. The probe needles provided in the three probe needle parts 24a to 24d are brought into contact with the connection terminals provided in the terminal parts 23a to 23d of the TFT substrate 2 (S2).

Next, the voltage control unit 42 controls the operation of the voltage application unit 36 to apply a voltage for resistance value inspection between the wirings to be inspected or between the wirings (S3), and the resistance measurement control unit 43 performs resistance measurement unit 37. Is controlled to measure the resistance value (electric resistance value) between the wirings to be inspected or between the wirings (S4).

Next, the defect determination unit 44 determines the presence or absence of a defect between the wirings to be inspected or the wirings based on the resistance value measurement result of S4 (S5). Specifically, the defect determination unit 44 compares the resistance value measurement result of S4 with the resistance value between the wiring or the wiring when there is no defect stored in the data storage unit 32 in advance, If the difference is less than a predetermined value, it is determined that there is no defect, and if it is greater than the predetermined value, it is determined that there is a defect.

FIG. 5A to FIG. 5C are explanatory diagrams schematically showing an example of a defective portion (wiring short-circuit portion) 25 generated in the pixel portion 21. FIG.

FIG. 5A shows an example of the defective portion 25 in which the wiring X and the wiring Y are short-circuited in the intersecting portion in the TFT substrate where the wiring X (for example, the scanning line) and the wiring Y (for example, the signal line) intersect. Is shown. The presence / absence and position of this type of defective portion 25 is switched to the probe needle to be conducted to the set of terminal portion 23a and terminal portion 23d or the set of terminal portion 23b and terminal portion 23c shown in FIG. The wirings Y1 to Y10 can be specified by measuring the resistance value between the wirings for each wiring.

FIG. 5B shows an example of the defective portion 25 in which the wirings of adjacent wirings X (for example, scanning lines or scanning lines and auxiliary capacitance wirings) are short-circuited. The presence / absence and position of this type of defect 25 is determined by switching the probe needle to be conducted to a pair of odd numbered terminal 23b and even numbered 23d, and measuring the resistance value between adjacent wires X1 to X10. Can be specified.

FIG. 5C shows an example of the defective portion 25 in which the wirings between adjacent wirings Y (for example, signal lines) are short-circuited. The presence / absence and position of this type of defective portion 25 is determined by switching the probe needle to be conducted to a pair of odd numbered terminals 23a and even numbered 23c, and measuring resistance values between adjacent wires Y1 to Y10. Can be specified.

When it is determined that there is a defect in S5, the defect determination unit 44 stores the wiring corresponding to the defect or the resistance value between the wirings in the data storage unit 32 (S6). In addition, the defect position specifying unit 46 determines whether or not it is necessary to perform an infrared inspection in order to specify the position of the defect (S7).

For example, as in the example shown in FIG. 5A, in the case where the defect portion 25 is generated at the intersection of the wiring X and the wiring Y, the resistance inspection is performed for every combination of the wiring X and the wiring Y in S4. If so, an abnormality is detected in the wiring X4 and the wiring Y4 by the resistance inspection between the wirings, and the position of the defective portion 25 can be specified. Therefore, in that case, the defect position specifying unit 46 determines that the infrared inspection is unnecessary.

However, since the number of combinations of the wiring X and the wiring Y is enormous, it takes a long time to measure the resistance value for all the combinations of the wiring X and the wiring Y. For example, in the case of a full high-definition liquid crystal panel, since there are 1080 wirings X and 1920 wirings Y, there are approximately 2.70 million combinations. For this reason, if resistance inspection is performed for all combinations, the tact time becomes long, and the inspection processing capability is greatly reduced, which is not realistic. Therefore, it is conceivable to reduce the number of resistance inspections by dividing the wiring X and the wiring Y into several groups and performing a resistance inspection for each group. For example, if resistance inspection is performed between all the wirings X and all the wirings Y, the number of resistance inspections is only one. However, when a resistance test is performed between the plurality of wirings X and the plurality of wirings Y, it is possible to detect the presence or absence of a short circuit between the wirings, but it is not possible to specify the position where the short circuit has occurred. In such a case, the defect position specifying unit 46 determines that an infrared inspection is necessary.

Further, as shown in FIGS. 5B and 5C, when the defect portion 25 is generated between the adjacent wirings, the defect is generated between the pair of adjacent wirings, for example, between the wiring X3 and the wiring X4. It can be specified that the portion 25 is present. However, the position of the defective portion 25 in the length direction of the wiring cannot be specified. For this reason, the defect position specifying unit 46 determines that infrared inspection is necessary to specify the position of the defective part 25.

When it is determined in S7 that an infrared inspection is necessary, the voltage control unit 42 controls the operation of the voltage application unit 36 to apply a voltage for infrared inspection between the wirings to be inspected or between the wirings (S8), and image pickup. The control unit 45 controls the operation of the infrared camera 4 to image the TFT substrate 2 (S9), and stores the captured infrared image data in the data storage unit 32.

The voltage value for infrared inspection is not particularly limited, and may be set as appropriate in consideration of the characteristics of the wiring or circuit to be inspected. The voltage value for infrared inspection may be set to a voltage value proportional to the square root of the resistance value measured in S4. In this case, since the calorific value per unit time can be made constant, the resistance of the short circuit path including the defect 25 depends on the type of the substrate, the location where the defect 25 occurs on the substrate, the cause of the short circuit of the defect 25, and the like. Even if the value fluctuates greatly, the calorific value per unit time can be made constant regardless of these factors.

Next, the defect position specifying unit 46 specifies the position of the defect based on the infrared image data (S10), and stores the specified position in the data storage unit 32 (S11).

FIG. 6A is an explanatory diagram showing a position A of a defect present in a part of the TFT substrate 2, and FIG. 6B is a diagram of an infrared image acquired by imaging an area including the defect with the infrared camera 4. It is explanatory drawing which shows an example, FIG.6 (c) is explanatory drawing which shows the image which expanded and image | photographed the said defect with the optical microscope. When there is a defect in the wiring or the like, the resistance value changes in the defect, so that heat is generated when a voltage is applied. For this reason, as shown in FIG. 6B, when there is a defect in the wiring, heat generation of the defective portion is detected by imaging using an infrared camera with a voltage applied to the wiring, The position of the defect can be specified.

When it is determined in S7 that the infrared inspection is unnecessary, that is, when the defect position can be specified using the resistance value measurement result of S4, the defect position specifying unit 46 specifies based on the resistance value measurement result. The defect position is stored in the data storage unit 32 (S11).

When it is determined in S5 that there is no defect, and after the defect position information is stored in S11, the control unit 31 determines whether or not the inspection of all the wirings to be inspected in the TFT substrate 2 being inspected or the inspection between the wirings has been completed. Is determined (S12).

Then, when it is determined in S12 that there is an uninspected inspection object, the control unit 31 returns to the process of S3 and inspects the next wiring or between the wirings.

On the other hand, if it is determined in S12 that the inspection has been completed for all inspection objects, the control unit 31 determines whether or not the inspection has been completed for all TFT substrates 2 in the mother substrate 1 under inspection (S13).

If there is an uninspected TFT substrate 2, the process returns to S 2 to inspect the next TFT substrate 2.

On the other hand, when it is determined in S13 that the inspection of all the TFT substrates 2 is completed, the control unit 31 ends the inspection process for the mother substrate 1.

(1-4. Effects of Defect Detection Device 100)
As described above, the defect detection apparatus 100 according to the present embodiment includes the gantry 12 that can be translated in the X-axis direction, which is parallel to the substrate surface of the mother substrate 1 placed on the alignment stage 11, and the above-described gantry 12. An infrared camera 4 attached to the gantry 12 so that the relative position with respect to the substrate surface in the Z-axis direction which is a direction perpendicular to the substrate surface of the mother substrate 1 is constant. Then, the inspection target wiring to which the voltage for infrared inspection is applied is imaged.

As a result, the infrared camera 4 is translated along a direction parallel to the substrate surface while keeping the position in the direction perpendicular to the substrate surface of the infrared camera 4 constant, and the inspection target portion (TFT to be inspected) on the mother substrate 1 is moved. It can be moved to a position according to the substrate 2). Therefore, it is possible to easily and accurately detect a defect in the inspection target portion (inspection target TFT substrate 2) in the mother substrate 1.

The infrared camera 4 is attached to the gantry 12 so as to be parallel to the substrate surface of the mother substrate 1 placed on the alignment stage 11 and parallel to the Y-axis direction that intersects the X-axis direction. It has been.

Therefore, the infrared camera 4 can be easily and appropriately moved to a position corresponding to the inspection target portion (TFT substrate 2 to be inspected) on the mother substrate 1.

In the present embodiment, the case where the defect detection processing of the TFT substrate (substrate circuit) 2 provided in the liquid crystal panel is performed by the defect detection device 100 has been described. However, the substrate to be subjected to the defect detection processing is not limited to this. The present invention can be applied to any substrate circuit in which wiring is formed on the substrate. For example, the present invention can be applied to a defect detection process for wiring of a substrate circuit provided in a display panel such as a plasma display or an organic EL display, or a solar battery panel.

In the present embodiment, the probe unit 3 has a shape corresponding to one TFT substrate 2, and each probe needle of the probe unit 3 is brought into contact with each connection terminal provided on the one TFT substrate 2. Although the configuration has been described, the present invention is not limited to this. For example, the shape of the probe unit 3 is made to correspond to the plurality of TFT substrates 2 placed on the alignment stage 11, and each probe needle of the probe unit 3 is attached to each connection terminal provided in the plurality of TFT substrates 2. It is good also as a structure made to contact.

Further, in the present embodiment, the configuration including only one infrared camera 4 has been described. However, a plurality of infrared cameras 4 may be provided, and the inspection target area may be imaged by the plurality of infrared cameras 4.

In this embodiment, the configuration in which the infrared camera 4 is movable in the X-axis direction and the Y-axis direction with respect to the alignment stage 11 has been described. However, the present invention is not limited to this, and at least the alignment stage 11 (on the alignment stage 11). It is only necessary that the position in the Z-axis direction with respect to the inspection target substrate) is constant.

For example, the infrared camera 4 may be attached to a fixed member that does not move relative to the alignment stage 11 in the X-axis direction and the Y-axis direction so that the position in the Z-axis direction is constant.

Further, the infrared camera 4 may be fixed so that the positions in the Y-axis direction and the Z-axis direction are constant with respect to the gantry 12 movable in the X-axis direction.

Further, the infrared camera 4 is fixed to a fixed member whose relative position in the X-axis direction and the Y-axis direction with respect to the alignment stage 11 is not moved, the position in the Z-axis direction is constant, and parallel to at least one of the X-axis direction and the Y-axis direction. It may be attached in a movable state.

Further, a laser irradiation device for correcting a defect portion may be mounted on the defect detection device 100. By mounting the laser irradiation apparatus, after the position of the defect portion is specified, the defect portion is irradiated with the laser, whereby the defect portion detection processing and defect correction processing can be performed continuously. In addition, the mounting method of said laser irradiation apparatus is not specifically limited, What is necessary is just a structure which can move a laser irradiation part to the position according to the defect part. For example, the above laser irradiation apparatus may be mounted on the gantry 12 or may be mounted on another support member different from the gantry 12.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope indicated in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

The present invention can be applied to a defect detection apparatus that detects defects such as wiring formed on a substrate. For example, the present invention can be applied to a defect detection device that detects defects such as wiring formed on a display panel such as a liquid crystal panel or a plasma display panel, or a substrate such as a solar battery panel.

1 Mother board (board)
2 TFT substrate (substrate circuit)
3 Probe unit (voltage application unit)
4 Infrared camera 10 Base 11 Alignment stage (stage)
12

Gantry

12a, 12b Leg portion

12c Beam portion

13a, 13b Guide rail 14

Guide rail

15a,

15b Mount portion

16a,

16b Guide rail

17a, 17b Probe support portion 21 Pixel portion (pixel region)
22 Peripheral circuit (Drive circuit, peripheral circuit area)
23a to 23d Terminal portions 24a to 24d Probe needle portion 25 Defect portion 28 Gantry moving means 29 Probe moving means 30 Camera moving means 31 Control section 32 Data storage section 33 Gantry moving means 34 Probe moving means 35 Camera moving means 36 Voltage applying section 37 Resistance measurement unit 38 Infrared camera 41 Position control unit 42 Voltage control unit 43 Resistance measurement control unit 44 Defect determination unit 45 Imaging control unit 46 Defect position specifying unit 100 Defect detection device

Claims

A defect detection apparatus for detecting defects in wiring formed on a substrate,
A stage on which the substrate is placed;
A voltage application unit for applying a voltage to the wiring to be inspected on the substrate;
A gantry placed across the stage,
An infrared camera that is disposed at a position facing the substrate surface of the substrate placed on the stage in the gantry and images the inspection target wiring to which a voltage is applied by the voltage application unit;
The gantry is movable in the X direction, which is a direction parallel to the substrate surface of the substrate placed on the stage, and the infrared camera is perpendicular to the substrate surface of the substrate placed on the stage. A defect detection apparatus, wherein the defect detection apparatus is attached to the gantry so that a relative position with respect to the substrate surface in the Z direction which is a direction is constant.
The infrared camera is attached to the gantry so as to be parallel to a substrate surface of a substrate placed on the stage and parallel to the Y direction which is a direction intersecting the X direction. The defect detection apparatus according to claim 1.
The voltage application unit includes a probe unit including a probe needle that contacts a connection terminal provided on the substrate,
The probe section is provided so as to be movable between a position where the probe needle contacts the connection terminal of the substrate placed on the stage and a position separated from the connection terminal. The defect detection apparatus according to claim 1.
One or a plurality of substrate circuits are formed on the substrate, and the connection terminal is provided at an outer edge of each substrate circuit,
The probe portion includes a frame portion having an opening having a shape corresponding to the shape of the outer edge portion of each substrate circuit, and the probe needle of the probe portion connects the substrate circuit to be inspected among the substrate circuits. The defect detection apparatus according to claim 3, wherein the substrate circuit is exposed through the opening when moved to a position in contact with the terminal.
The substrate circuit is a substrate circuit provided in a display panel, and includes a pixel region in which a large number of pixel circuits are disposed, and a peripheral circuit region disposed around the pixel region,
When the probe unit is moved to a position where the probe needle of the probe unit contacts the connection terminal of the substrate circuit to be inspected, the entire pixel region and the peripheral circuit region are passed through the opening. The defect detection apparatus according to claim 4, wherein the defect detection apparatus is exposed.
In the infrared camera, the entire area of the opening can be imaged in a single imaging process when the probe section is moved to a position where the probe needle of the probe section contacts the connection terminal of the substrate circuit to be inspected. The defect detection apparatus according to claim 4, wherein the defect detection apparatus is a defect detection apparatus.