JP2018194373A - Substrate inspection device, inspection jig, and substrate inspection method - Google Patents

Abstract

To provide a substrate inspection device with which it is easy to detect a defect in the joined part of an electroconductive material, an inspection jig used therefor, and a substrate inspection method.SOLUTION: Provided is a substrate inspection device 1 for inspecting a touch panel 100 on which a transparent electrode 13 and a first connection electrode 14 joined to the transparent electrode 13 so as to overlap in the thickness direction are formed. The substrate inspection device 1 comprises: a detection electrode 31 arranged facing a junction J1 between the transparent electrode 13 and the first connection electrode 14 at a position closer to the transparent electrode 13 side than to the first connection electrode 14 in the junction J1; a detection electrode 21 arranged facing the junction J1 at a position closer to the first connection electrode 14 side than to the transparent electrode 13 in the junction J1; a current supply part 4 for supplying a current to the junction J1; and a voltage detection part 5 for detecting a potential difference V between the detection electrode 31 and the detection electrode 21.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a substrate inspection apparatus for inspecting a substrate, an inspection jig used therefor, and a substrate inspection method.

  In recent years, with the rapid spread of electronic devices such as smartphones and tablets, the demand for a touch panel for detecting a position touched by a human finger or stylus pen is particularly increased. As such a touch panel, there is known a resistive film type touch panel in which two resistive films are arranged opposite to each other on a touch surface and a touch position is detected from a resistance value when a user touches the touch surface.

  On the other hand, in recent years, capacitive touch panels have been widely used in which transparent electrodes arranged in a lattice pattern are arranged on the touch surface and the touch position is detected based on the capacitance generated when the user touches the panel with a finger. ing. The capacitive touch panel has a plurality of transparent electrodes extending in the X direction on a transparent substrate such as glass so that two-dimensional coordinates of XY are set on the panel surface and correspond to the XY coordinates, A plurality of transparent electrodes extending in the Y direction are arranged to be opposed to each other.

  As an inspection method for such a capacitive touch panel, there is an inspection method in which a touch probe is brought into contact with a sensor electrode extending in the X and Y directions instead of a human finger and the potential of a lead wire connected to the sensor electrode is measured. It is known (for example, refer to Patent Document 1).

JP 2011-90358 A

  By the way, when joining the sensor electrode and the lead wire as described above, if the joining state of the joining portion is insufficient, a resistance value may be generated at the joining portion. However, the junction resistance generated at the junction is smaller than the resistance value of the sensor electrode. Therefore, in the technique described in Patent Document 1, the junction resistance due to the joint failure is small with respect to the resistance value of the entire sensor electrode at the normal time, and it is not easy to detect the failure.

  Such a defect in the joint portion is not limited to the electrostatic capacity method, and may occur in common in a resistive film type touch panel and other devices having a joint portion of a conductive material.

  The objective of this invention is providing the board | substrate inspection apparatus which is easy to detect the defect of the junction part of an electrically-conductive material, the inspection jig used for this, and a board | substrate inspection method.

  A substrate inspection apparatus according to the present invention inspects a substrate on which a conductive first main electrode and a conductive first connection electrode bonded so as to overlap the first main electrode in the thickness direction are formed. A first substrate that is disposed on the first main electrode side of the bonding portion between the first main electrode and the first connection electrode on the first main electrode side so as to face the bonding portion. A detection electrode; a second detection electrode disposed on the first connection electrode side with respect to the first main electrode in the joint; and a current supply unit configured to supply current to the joint; A voltage detection unit configured to detect a potential difference between the first detection electrode and the second detection electrode;

  The substrate inspection method according to the present invention inspects a substrate on which a conductive first main electrode and a conductive first connection electrode joined so as to overlap the first main electrode in the thickness direction are formed. An inspection method for a substrate, wherein the first detection electrode is opposed to the joint on the first main electrode side with respect to the first connection electrode in the joint between the first main electrode and the first connection electrode. A first detection electrode arrangement step for arranging, a second detection electrode arrangement step for arranging the second detection electrode on the first connection electrode side with respect to the first main electrode at the junction, and facing the junction. A current supply step of supplying a current to the junction, and a voltage detection step of detecting a potential difference between the first detection electrode and the second detection electrode.

  According to these configurations, since a current is supplied to the junction between the first main electrode and the first connection electrode, the potential of the first main electrode at the junction increases when the resistance value of the junction increases due to poor bonding or the like. And the potential of the first connection electrode is different. Here, the first detection electrode is disposed opposite to the joint on the first main electrode side of the joint and is electrostatically coupled. Further, the second detection electrode is disposed opposite to the joint on the first connection electrode side of the joint and is electrostatically coupled. As a result, a potential difference between the first detection electrode and the second detection electrode can be detected via the coupling capacitance. Since this potential difference changes according to the magnitude of the junction resistance, if this potential difference can be detected, it is easy to detect a defect in the junction between the first main electrode and the first connection electrode, which are conductive materials. It becomes.

  The substrate further includes a conductive second connection electrode joined to the first main electrode so as to be spaced apart from the first connection electrode and overlap the first main electrode in the thickness direction. It is preferable that a supply part supplies an electric current to the said junction part by sending an electric current between said 1st connection electrode and said 2nd connection electrode.

  According to this configuration, since the first connection electrode and the second connection electrode are separated from each other and joined to the first main electrode, a current flows between the first connection electrode and the second connection electrode. Thus, it is possible to supply a current to the junction.

  The first main electrode extends along a predetermined first direction, and the substrate extends along a second direction intersecting with the first direction and at a position intersecting with the first main electrode. A second main electrode opposed to the first main electrode, and a conductive second connection electrode joined to the second main electrode so as to be spaced apart from the intersecting position and overlap the second main electrode in the thickness direction The current supply unit may supply a current to the joint by flowing a current between the first connection electrode and the second connection electrode.

  According to this configuration, since the first main electrode joined with the first connection electrode and the second main electrode joined with the second connection electrode intersect and face each other, the first main electrode The second main electrode is electrostatically coupled. Therefore, by passing a current between the first connection electrode and the second connection electrode, it is possible to supply a current to the junction through the electrostatic coupling at the intersection.

  In addition, a plurality of sets of the first main electrode, the first connection electrode, and the joint portion are formed on the substrate, and the first detection electrode and the second detection electrode are the plurality of sets. A plurality of pairs are provided corresponding to each of the joints, and the substrate inspection apparatus includes a first jig for holding the plurality of first detection electrodes integrally corresponding to the arrangement of the plurality of joints, It is preferable to further include a second jig that integrally holds the plurality of second detection electrodes in correspondence with the arrangement of the plurality of joint portions.

  According to this configuration, the plurality of first detection electrodes are integrally held by the first jig so as to correspond to the arrangement of the plurality of joint portions, and the plurality of second detection electrodes are formed by the second jig. Are integrally held corresponding to the arrangement of the joints. As a result, it is easy to dispose the plurality of first detection electrodes and the plurality of second detection electrodes opposite to the plurality of joints.

  The first main electrode and the first connection electrode may be made of different materials.

  When the materials of the first main electrode and the first connection electrode are different from each other, poor bonding is likely to occur. Therefore, such a substrate is suitable as a substrate to be inspected by the above-described substrate inspection apparatus or substrate inspection method.

  The substrate may be a touch panel display, and the first main electrode may be a transparent electrode.

  Since the touch panel display uses a transparent electrode as the first main electrode, the materials of the first main electrode and the first connection electrode are different from each other for connection with the wiring material. When the materials of the first main electrode and the first connection electrode are different from each other, poor bonding is likely to occur. Therefore, such a substrate is suitable as a substrate to be inspected by the above-described substrate inspection apparatus or substrate inspection method.

  Moreover, it is preferable to further include a determination unit that determines the quality of the joint based on the potential difference detected by the voltage detection unit.

  According to this configuration, the determination unit can determine the quality of the joint.

  In addition, the determination unit determines whether or not the junction is good based on the potential difference detected by the voltage detection unit during a period in which a predetermined first current is supplied to the junction as the current by the current supply unit. A first determination step of determining the second current detected by the voltage detection unit during a period in which a second current in a direction opposite to the first current is supplied to the junction as the current by the current supply unit. It is preferable to execute a second determination step of determining the quality of the joint based on the potential difference.

  Depending on the bonding state of the first main electrode and the first connection electrode, a rectifying action may occur at the bonded portion. However, according to this configuration, even if a rectifying action occurs at the joint, the first determination step for determining pass / fail by passing the first current through the joint and the second in the direction opposite to the first current Since the current is passed through the joint and the second determination step for determining pass / fail is executed, it is possible to detect a defect in any of the determination steps.

  Moreover, it is preferable that the said current supply part supplies the periodic current from which a magnitude | size changes periodically as the said current.

  According to this configuration, the voltage detection unit detects a potential difference between the first detection electrode and the second detection electrode via the coupling capacitance. When the periodic current is supplied to the coupling portion between the first detection electrode and the second detection electrode, the impedance of the coupling capacitance is reduced, and therefore the potential difference can be easily detected by the voltage detection unit.

  An inspection jig according to the present invention is an inspection jig attached to the above-described substrate inspection apparatus, and the substrate includes a set of the first main electrode, the first connection electrode, and the joint portion. A plurality of first detection electrodes are provided corresponding to each of the plurality of sets of joints, and the plurality of first detection electrodes are integrally formed corresponding to the arrangement of the plurality of joints. Hold.

  According to this configuration, the plurality of first detection electrodes are integrally held by the inspection jig so as to correspond to the arrangement of the plurality of joint portions. As a result, it becomes easy to dispose the plurality of first detection electrodes opposite to the plurality of joint portions.

  An inspection jig according to the present invention is an inspection jig attached to the above-described substrate inspection apparatus, and the substrate includes a set of the first main electrode, the first connection electrode, and the joint portion. A plurality of second detection electrodes are provided corresponding to each of the plurality of sets of joints, and the plurality of second detection electrodes are integrally formed corresponding to the arrangement of the plurality of joints. Hold.

  According to this configuration, the plurality of second detection electrodes are integrally held by the inspection jig so as to correspond to the arrangement of the plurality of joint portions. As a result, it becomes easy to dispose the plurality of second detection electrodes opposite to the plurality of joints.

  With the substrate inspection apparatus and the substrate inspection method having such a configuration, it becomes easy to detect a defect in the joint portion of the conductive material.

It is explanatory drawing which shows notionally an example of a structure of the board | substrate inspection apparatus using the board | substrate inspection method which concerns on one Embodiment of this invention. It is explanatory drawing for demonstrating the structure of the touchscreen shown in FIG. 1, a 1st jig | tool, and a 2nd jig | tool. It is explanatory drawing for demonstrating operation | movement of the board | substrate inspection apparatus shown in FIG. It is explanatory drawing for demonstrating operation | movement of the board | substrate inspection apparatus shown in FIG. It is a circuit diagram which shows the equivalent circuit comprised by a board | substrate inspection apparatus and a touch panel in the test | inspection state with which the touch panel was clamped with the 1st jig | tool and the 2nd jig | tool. It is a flowchart which shows an example of the board | substrate inspection method by the board | substrate inspection apparatus shown in FIG. It is explanatory drawing which shows an example of the test | inspection electric current i and the electric potential difference V. FIG. It is explanatory drawing which shows another example of test | inspection electric current. It is explanatory drawing which shows another example of the touchscreen used as test | inspection object, and an example of the test | inspection jig | tool for test | inspecting the touchscreen. It is explanatory drawing for demonstrating operation | movement of the board | substrate inspection apparatus which concerns on 2nd embodiment. It is a circuit diagram which shows the equivalent circuit comprised by a board | substrate inspection apparatus and a touch panel in the test | inspection state with which the touch panel was clamped with the 1st jig | tool and the 2nd jig | tool.

Embodiments according to the present invention will be described below with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted.
(First embodiment)

  FIG. 1 is an explanatory diagram conceptually showing an example of the configuration of a substrate inspection apparatus using a substrate inspection method according to an embodiment of the present invention. A substrate inspection apparatus 1 shown in FIG. 1 includes a first jig 3 (inspection jig), a second jig 2 (inspection jig), a current supply unit 4, a voltage detection unit 5, a contact pin P, and a control unit 6. Is provided.

  A touch panel 100 (substrate) to be inspected is connected to the substrate inspection apparatus 1 shown in FIG. In the touch panel 100 shown in FIG. 1, XY coordinates are set. In the example shown in FIG. 1, the depth direction in the drawing is the X axis and the left and right direction is the Y axis. The touch panel 100 is disposed so as to be sandwiched between the first jig 3 and the second jig 2 that are arranged to face each other. The first jig 3 and the second jig 2 can be moved up and down by a lifting mechanism (not shown).

  In addition, the 1st jig | tool 3 and the 2nd jig | tool 2 are not restricted to the example raised / lowered by the raising / lowering mechanism not shown. The touch panel 100 may be configured to be sandwiched between the first jig 3 and the second jig 2 by a user's manual operation.

  In addition, although the touch panel for touch panel displays was shown as an example of a board | substrate, the board | substrate to be test | inspected does not necessarily need to be a touch panel, for example, for a printed wiring board, a flexible substrate, a ceramic multilayer wiring board, a liquid crystal display or a plasma display. Various substrates such as an electrode plate, a package substrate for a semiconductor package, and a film carrier may be used.

  The touch panel 100 mainly includes a plate-like base material 11, an X electrode 12 (set) formed on the surface of the base material 11, a tab terminal 17, a cover film F, and the like. The cover film F is adhered to the base material 11 so as to expose the tab terminal 17 while covering the X electrode 12. In FIG. 1, the electrode and the cover film are described only on the upper surface side of the base material 11, but the electrode and the cover film may be provided also on the lower surface side of the base material 11.

  The current supply unit 4 is, for example, a power supply circuit that supplies an AC inspection current i. The current supply unit 4 may be a constant current circuit or a constant voltage circuit as long as it can supply the inspection current i.

  The contact pin P is provided corresponding to the plurality of tab terminals 17. The contact pin P can be moved up and down by, for example, a lifting mechanism (not shown). At the time of inspection, each contact pin P is brought into contact with each tab terminal 17. Each contact pin P is connected to the current supply unit 4 via a switching circuit (not shown). As a result, the current supply unit 4 flows the inspection current i between the two tab terminals 17 selected from the plurality of tab terminals 17.

  The voltage detection unit 5 is a voltage detection circuit configured using, for example, an amplifier circuit AMP shown in FIG. 3 and an analog-digital converter (not shown). The voltage detection unit 5 is connected to detection electrodes 21 and 22 described later and detection electrodes 31 and 32 through a switching circuit (not shown). Thereby, the voltage detection unit 5 measures the potential difference V between the detection electrode 21 and the detection electrode 31 and the potential difference V between the detection electrode 22 and the detection electrode 32 and transmits them to the control unit 6.

  The control unit 6 includes, for example, a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a RAM (Random Access Memory) that temporarily stores data, and a non-volatile storage unit that stores predetermined control programs and the like. And peripheral circuits thereof. The control unit 6 controls the current supply by the current supply unit 4, receives the potential difference V detected by the voltage detection unit 5, or the first jig 3 and the second jig 2 by a lifting mechanism (not shown). And the contact pin P is moved up and down. The control unit 6 functions as the determination unit 61 by executing the control program.

  As shown in FIG. 2, the determination unit 61 is based on the potential difference detected by the voltage detection unit 5 during the period in which the inspection current i (first current) is supplied to the junctions J1 and J2 by the current supply unit 4. The first determination step for determining the quality of the joints J1 and J2 and the inspection current i (second current) in the direction opposite to the first determination step is supplied to the joints J1 and J2 by the current supply unit 4. A second determination step is performed in which the quality of the joints J1 and J2 is determined based on the potential difference V detected by the voltage detection unit 5 during the period.

  In addition, the determination part 61 does not necessarily need to perform a 1st and 2nd determination process, You may perform only a 1st determination process. Alternatively, the control unit 6 may not include the determination unit 61. The control unit 6 may be configured to notify the user by storing the potential difference V in a storage unit or by displaying the potential difference V using a display (not shown) or the like.

  FIG. 2 is an explanatory diagram for explaining the configuration of the touch panel 100, the first jig 3, and the second jig 2 shown in FIG. In FIG. 2, the cover film F is not shown. A plurality of X electrodes 12 extending along the X-axis direction (first direction) and wirings 16 connected to both ends of each X electrode 12 are formed on one surface of the substrate 11. One end of each wiring 16 extends to the end of the base material 11 and serves as a tab terminal 17. The tab terminal 17 is not covered with the cover film F, and a probe and a connector can be connected to the tab terminal 17 from the outside.

  The X electrode 12 is joined to, for example, a substantially strip-shaped transparent electrode 13 (first main electrode) extending along the X-axis direction (first direction) so as to overlap in the thickness direction at one end of the transparent electrode 13. The conductive first connection electrode 14 and the second conductive electrode joined to the transparent electrode 13 so as to be separated from the first connection electrode 14 at the other end of the transparent electrode 13 and overlap the transparent electrode 13 in the thickness direction. And a connection electrode 15. The portion where the transparent electrode 13 and the first connection electrode 14 are overlapped and bonded is the bonding portion J1, and the portion where the transparent electrode 13 and the second connection electrode 15 are overlapped and bonded is the bonding portion J2.

  The transparent electrode 13 is made of a transparent conductive material such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). The first connection electrode 14 and the second connection electrode 15 are made of a conductive material such as copper (Cu), for example. That is, the transparent electrode 13 and the first connection electrode 14 and the second connection electrode 15 are made of different materials. The transparent electrode 13, the first connection electrode 14, and the second connection electrode 15 may be the same material. Further, the first main electrode may not be a transparent electrode.

  The first connection electrode 14 and the second connection electrode 15 are each connected to the other end of the wiring 16 and are electrically connected to the tab terminal 17 by the wiring 16. The transparent electrode 13 is limited in materials that can be used because it needs to be transparent, and a resistance Rx of about 100 kΩ is generated. The wiring 16 is preferably made of a low resistance and inexpensive material, and a copper wiring is usually used. Therefore, the first connection electrode 14 and the second connection electrode 15 are provided in order to connect the transparent electrode 13 made of a different metal material and the wiring 16.

  Since the first connection electrode 14 and the second connection electrode 15 and the transparent electrode 13 are made of different materials, if the bonding is insufficient, the bonding resistance R1 of the bonding portion J1 and the bonding resistance R2 of the bonding portion J2 increase. To do. Furthermore, if the joints J1 and J2 are not sufficiently joined, the joint resistances R1 and R2 may increase due to deterioration over time or disconnection may occur. Further, when the junction resistances R1 and R2 increase, the touch position detection accuracy by the touch panel 100 may be lowered.

  Therefore, the substrate inspection apparatus 1 inspects the bonding state of the bonding portions J1 and J2 by detecting the bonding resistances R1 and R2.

  The first jig 3 mainly includes, for example, a plate-like plate 30 and plate-like detection electrodes 31 and 32 (first detection electrodes) formed on one surface of the plate 30. . A plurality of detection electrodes 31 are provided corresponding to the plurality of joints J1. A plurality of detection electrodes 32 are provided corresponding to the plurality of joints J2. The detection electrodes 31 and 32 are arranged on one surface of the plate 30 so as to face the joints J1 and J2, respectively. Thereby, the 1st jig | tool 3 hold | maintains each detection electrode 31 and 32 integrally.

  At the time of inspection, one surface (the upper surface in FIG. 2) of the first jig 3 is brought into contact with the surface on the transparent electrode 13 side (the lower surface in FIG. 2) of the joints J1 and J2 of the touch panel 100. Thus, the detection electrodes 31 and 32 are arranged to face the joints J1 and J2 with the insulating base material 11 interposed therebetween. That is, each detection electrode 31 and 32 is spaced apart from each junction part J1 and J2, and is opposingly arranged.

  Then, as shown in FIGS. 3 and 4, the transparent electrode 13 and each detection electrode 31 at each joint J1 are electrostatically coupled to generate a coupling capacitance C31. The transparent electrode 13 and each detection electrode 32 in each joint J2 are electrostatically coupled to generate a coupling capacitance C32.

  In addition, when the electrode is formed in the surface by the side of the 1st jig | tool 3 of the base material 11, and the cover film is affixed, each detection electrode 31 and 32 is spaced apart from each junction part J1, J2 and a cover film. Thus, they are arranged to face each other. Further, a cover film may not be provided on the first jig 3 side of the substrate 11, an insulating film may be provided on one side of the first jig 3, or the touch panel 100 Alternatively, the first jig 3 may be opposed to the first jig 3.

  The second jig 2 mainly includes, for example, a plate-shaped plate 20 and plate-shaped detection electrodes 21 and 22 (second detection electrodes) formed on one surface (the lower surface in FIG. 2) of the plate 20. It is prepared for. A plurality of detection electrodes 21 are provided corresponding to the plurality of joints J1. A plurality of detection electrodes 22 are provided corresponding to the plurality of joints J2. The detection electrodes 21 and 22 are arranged on one surface of the plate 20 so as to face the joints J1 and J2, respectively. Thereby, the 2nd jig | tool 2 hold | maintains each detection electrode 21 and 22 integrally.

  At the time of inspection, one surface (the lower surface in FIG. 2) of the second jig 2 is the surface on the first connection electrode 14 side of the joint portion J1 and the second connection electrode 15 side of the joint portion J2 (the upper surface in FIG. 2). ). Thus, the detection electrodes 21 and 22 are arranged to face the joints J1 and J2 via the insulating cover film F. In other words, the detection electrodes 21 and 22 are arranged opposite to each other at a distance from the joints J1 and J2.

  Then, as shown in FIGS. 3 and 4, the first connection electrode 14 and each detection electrode 21 in each joint J <b> 1 are electrostatically coupled to generate a coupling capacitance C <b> 21. The second connection electrode 15 and each detection electrode 22 at each joint J2 are electrostatically coupled to generate a coupling capacitance C22.

  The 1st jig | tool 3 and the 2nd jig | tool 2 may be manufactured according to arrangement | positioning of junction part J1, J2 formed in the board | substrate to be examined, and may be made removable with respect to the board | substrate inspection apparatus 1 main body. . Thereby, when the board | substrate to be examined is changed, the 1st jig | tool 3 and the 2nd jig | tool 2 which were manufactured according to the board | substrate after a change are changed into the 1st jig | tool 3 and the 2nd jig | tool 2 before a change. Can be exchanged for.

  Note that the touch panel 100 may not include the cover film F, and an insulating film may be disposed on one side of the second jig 2, or the second jig may be separated from the touch panel 100. 2 may be opposed.

  3 and 4 are explanatory diagrams for explaining the operation of the substrate inspection apparatus 1 shown in FIG. FIG. 5 is a circuit diagram illustrating an equivalent circuit configured by the substrate inspection apparatus 1 and the touch panel 100 in an inspection state in which the touch panel 100 is sandwiched between the first jig 3 and the second jig 2. FIG. 6 is a flowchart showing an example of a substrate inspection method by the substrate inspection apparatus 1 shown in FIG.

  First, for example, with respect to the touch panel 100 held horizontally above the first jig 3 by a holding mechanism (not shown), the control unit 6 raises the first jig 3 and makes contact with the lifting mechanism (not shown). Let Accordingly, the detection electrodes 31 and 32 (first detection electrode) are connected to the joint J1 on the transparent electrode 13 (first main electrode) side of the first connection electrode 14 and second connection electrode 15 in the joints J1 and J2. , J2 (step S1: first detection electrode arrangement step).

  Next, the control unit 6 causes the second jig 2 and the contact pin P to be lowered and brought into contact with the touch panel 100 held horizontally below the second jig 2 by an elevator mechanism (not shown). As a result, the detection electrodes 21 and 22 (second detection electrodes) are connected to the joint portion J1 on the first connection electrode 14 and second connection electrode 15 side with respect to the transparent electrode 13 (first main electrode) in the joint portions J1 and J2. , J2 is arranged to face (step S2: second detection electrode arrangement step). Further, the contact pin P comes into contact with the tab terminal 17. Thereby, the inspection state shown in FIGS. 3 and 4 is obtained, and the equivalent circuit shown in FIG. 5 is configured.

  Next, the determination unit 61 causes the current supply unit 4 to supply the inspection current i as the first current, for example, in the direction from the first connection electrode 14 to the second connection electrode 15 (step S3: first current supply step). ). Thereby, the inspection current i flows through the junction J1, the transparent electrode 13, and the junction J2, and the inspection current i flows through the series circuit of the junction resistance R1, the resistance Rx, and the junction resistance R2 shown in FIG.

  Next, during the period in which the inspection current i is supplied as the first current, the voltage detection unit 5 causes the potential difference V between the detection electrode 31 and the detection electrode 21 or between the detection electrode 32 and the detection electrode 22. Is detected (step S4: voltage detection step). When the current supply unit 4 outputs a voltage of 10 Vrms, for example, the inspection current i supplied from the current supply unit 4 is approximately 10 Vrms / 100 kΩ = 0.1 mAms. When, for example, 1 kΩ is generated as the junction resistance R1 of the junction J1, the surface potential difference V between the surface of the transparent electrode 13 and the surface of the first connection electrode 14 of the junction J1 is 0.1 mA × 1 kΩ = 0.1 Vrms. Become.

  As shown in FIGS. 3 and 4, the transparent electrode 13 and the detection electrode 31 in the joint J1 are electrostatically coupled to generate a coupling capacitance C31, and the first connection electrode 14 and the detection electrode 21 in the joint J1 are static. Since the coupling capacitance C21 is generated due to the electrical coupling, as shown in FIG. 5, the voltage detection unit 5 calculates the potential difference V generated at the junction resistance R1 by the inspection current i flowing through the junction resistance R1 of the junction J1. , And detected through the coupling capacitors C21 and C31.

  Further, the transparent electrode 13 and the detection electrode 32 at the junction J2 are electrostatically coupled to generate a coupling capacitance C32, and the second connection electrode 15 and the detection electrode 22 at the junction J2 are electrostatically coupled to form a coupling capacitance C22. Therefore, as shown in FIG. 5, the voltage detection unit 5 causes the potential difference V generated in the junction resistance R2 when the inspection current i flows to the junction resistance R2 of the junction J2 through the coupling capacitors C22 and C32. To detect.

  If the joints J1 and J2 are well joined, the joint resistances R1 and R2 are reduced. If the joints J1 and J2 are poorly joined, the joint resistances R1 and R2 are increased. If the junction resistances R1 and R2 are small, the potential difference V is small. If the junction resistances R1 and R2 are large, the potential difference V is large. Therefore, the potential difference V can be used as information indicating whether or not the joining of the joint portions J1 and J2 is good.

  Since the substrate inspection apparatus 1 can detect the potential difference V in a non-contact manner by causing the detection electrodes 21, 22, 31, and 32 to face the joints J 1 and J 2, the surface of the touch panel 100 is covered with the cover film F. Even if it is broken, the potential difference V can be detected, and the touch panel 100 can be inspected based on the potential difference V.

  FIG. 7 is an explanatory diagram showing an example of the inspection current i supplied in steps S3 and S6 and the potential difference V detected in steps S4 and S7. In FIG. 7, the inspection current i is an alternating current, and the phase of 0 ° to 180 ° having a polarity of + corresponds to the first current supply process of step S3.

  Next, the determination unit 61 compares the absolute value | V | of the potential difference V with a preset reference voltage Vref (step S5: first determination step). If the joints J1 and J2 are poor, the absolute value | V | of the potential difference V is equal to or higher than a preset reference voltage Vref as shown in FIG. Therefore, if the potential difference | V | is equal to or higher than the reference voltage Vref (NO in step S5), the determination unit 61 determines that the joint to be inspected is defective (step S9) and ends the process.

  On the other hand, if the junctions J1 and J2 are well joined, the absolute value | V | of the potential difference V is less than the reference voltage Vref as shown in FIG. Therefore, if the potential difference | V | does not satisfy the reference voltage Vref (YES in step S5), the determination unit 61 proceeds to step S6 to perform a second determination step.

  In step S6, the determination unit 61 causes the current supply unit 4 to supply the inspection current i as the second current in the direction opposite to that in step S3, for example, in the direction from the second connection electrode 15 to the first connection electrode 14 ( Step S6: Second current supply step). As a result, the inspection current i flows through the series circuit of the junction resistance R1, the resistance Rx, and the junction resistance R2 in the direction opposite to that in step S3. As shown in FIG. 7, the phase 180 ° to 360 ° in which the polarity of the inspection current i is − corresponds to the second current supply process in step S6.

  Next, during the period in which the inspection current i is supplied as the second current, the voltage detection unit 5 causes the potential difference V between the detection electrode 31 and the detection electrode 21 or between the detection electrode 32 and the detection electrode 22. Is detected (step S7: voltage detection step). Since the potential difference V is related to the failure of the joints J1 and J2, detecting the potential difference V makes it easy to detect the failure of the joints J1 and J2.

  In step S7, if the junctions J1 and J2 are well joined, the absolute value | V | of the potential difference V is less than the reference voltage Vref as shown in FIG.

  Therefore, if the potential difference | V | does not satisfy the reference voltage Vref (YES in step S8), the determination unit 61 determines that the joint to be inspected is good (step S10) and ends the process.

  On the other hand, there is a possibility that a rectifying action may occur when two kinds of metals come into contact with each other at the joints J1 and J2. When the rectifying action occurs, as shown in FIG. 7B, in step S4, the junctions J1 and J2 become low resistance in the direction of the first current, and the potential difference | V | satisfies the reference voltage Vref. There will be no low voltage. On the other hand, in step S7, the junctions J1 and J2 have a high resistance with respect to the direction of the second current, and the potential difference | V | rises above the reference voltage Vref.

  Therefore, if the potential difference | V | is equal to or higher than the reference voltage Vref (NO in step S8), the determination unit 61 determines that the joint to be inspected is defective (step S9) and ends the process. Thereby, even if it is a case where a rectification effect | action arises in joining part J1, J2, the defect can be detected. Therefore, it becomes easy to detect defects in the joints J1 and J2. Hereinafter, the processes of steps S1 to S10 are executed for all the joints J1 and J2.

  It is not always necessary to execute steps S6 to S8. If the potential difference | V | does not satisfy the reference voltage Vref in step S5 (YES in step S5), a good determination may be made in step S10.

  The inspection current i is not necessarily limited to an alternating current, and the inspection current i is not limited to an example in which the positive polarity portion is the first current and the negative polarity portion is the second current. For example, as shown in FIG. 8, in step S3, a positive periodic current is supplied as the inspection current i as the first current, and in step S6, a negative periodic current is supplied as the inspection current i as the second current. You may do it.

In addition, the inspection current i is not necessarily limited to a periodic current whose magnitude varies periodically, such as an alternating current, and may be a direct current. However, it is more preferable that the inspection current i be a periodic current because the impedance of the coupling capacitors C21, C22, C31, and C32 decreases, and as a result, the detection of the potential difference V by the voltage detector 5 becomes easier.
(Second embodiment)

  In the first embodiment, the substrate inspection apparatus 1 for inspecting the touch panel 100 in which the first connection electrode 14 is provided at one end and the second connection electrode 15 is provided at the other end of the transparent electrode 13 (first main electrode). In the second embodiment, the touch panel 100a has a structure in which the connection target electrode is provided only at one end of the first main electrode and the other end is an open end. An example of the substrate inspection apparatus 1a to be inspected will be described.

  FIG. 9 is an explanatory diagram showing another example of a touch panel to be inspected and an example of an inspection jig for inspecting the touch panel. The touch panel 100a (substrate) shown in FIG. 9 is different from the touch panel 100 shown in FIG. 2 on the X electrode 12a of the base material 11 and a plurality of Y electrodes 40 (a set) extending along the Y-axis direction (second direction). ), A wiring 18 connected to one end of each Y electrode 40, a point where the end of the wiring 18 is a tab electrode 19, and an X electrode. 12a is different in that the second connection electrode 15 is not provided and the second connection electrode 15 is provided in the Y electrode 40.

  The X electrode 12a and the Y electrode 40 are insulated by an unillustrated insulating layer. The Y electrode 40 has a configuration in which the first connection electrode 14 is removed from the X electrode 12.

  In the substrate inspection apparatus 1a, the arrangement of the detection electrodes provided on the first jig 3a and the second jig 2a is changed in accordance with the arrangement of the joints J1 and J2 on the touch panel 100a. .

  The 1st jig | tool 3a is a point provided with the detection electrode 33 which opposes the junction part J2 of the Y electrode 40 instead of the detection electrode 32 which opposes the junction part J2 of the X electrode 12 with the 1st jig | tool 3. Become. The 2nd jig | tool 2a is a point provided with the detection electrode 23 which opposes the junction part J2 of the Y electrode 40 instead of the detection electrode 22 which opposes the junction part J2 of the X electrode 12 with the 2nd jig | tool 2. Become.

  The contact pin P is in contact with the tab terminals 17 and 19, and the current supply unit 4 supplies an inspection current i between the tab terminals 17 and 19. The voltage detection unit 5 detects the potential difference between the detection electrodes 33 and 23 as a potential difference V instead of the potential difference between the detection electrodes 32 and 22 in steps S4 and S7.

  In other respects, the substrate inspection apparatus 1a is configured in the same manner as the substrate inspection apparatus 1, and therefore the description thereof will be omitted. Hereinafter, the operation of the substrate inspection apparatus 1a will be described. FIG. 10 is an explanatory diagram for explaining the operation of the substrate inspection apparatus 1a. FIG. 11 is a circuit diagram showing an equivalent circuit configured by the substrate inspection apparatus 1a and the touch panel 100a in an inspection state in which the touch panel 100a is sandwiched between the first jig 3a and the second jig 2a.

  At the time of inspection, one surface (upper surface in FIG. 9) of the first jig 3a is brought into contact with one surface (lower surface in FIG. 9) of the touch panel 100a. Thus, the detection electrodes 31 and 33 are disposed to face the transparent electrode 13 side of the joints J1 and J2 with the base material 11 interposed therebetween. That is, each detection electrode 31 and 33 is spaced apart from each joint part J1 and J2, and is opposingly arranged.

  Then, as shown in FIG. 10, the transparent electrode 13 and each detection electrode 31 in each joint J1 are electrostatically coupled to generate a coupling capacitance C31. The transparent electrode 13 and each detection electrode 33 in each joint J2 are electrostatically coupled to generate a coupling capacitance C33.

  Further, one surface (the lower surface in FIG. 9) of the second jig 2a is brought into contact with the other surface (the upper surface in FIG. 9) of the touch panel 100a. Thereby, each detection electrode 21 is arranged to face the first connection electrode 14 side of each joint portion J1 through the cover film F, and each detection electrode 23 is arranged in the second portion of each joint portion J2 through the cover film F. It is arranged opposite to the connection electrode 15 side. That is, the detection electrodes 21 and 23 are arranged opposite to each other with the joints J1 and J2.

  Then, as shown in FIG. 10, the first connection electrode 14 and each detection electrode 21 at each joint J1 are electrostatically coupled to generate a coupling capacitance C21. The second connection electrode 15 and each detection electrode 23 in each joint J2 are electrostatically coupled to generate a coupling capacitance C23.

  Further, the X electrode 12a and the Y electrode 40 cross each other, and are arranged to face each other through an insulating layer (not shown) at the crossing position. As a result, the X electrode 12a and the Y electrode 40 are electrostatically coupled at the crossing position, and a coupling capacitance C is generated.

  In this state, assuming that the junction resistances of the junctions J1 and J2 are R1, R2, the resistance of the transparent electrode 13 in the X electrode 12a is Rx, and the resistance of the transparent electrode 13 in the Y electrode 40 is Ry, the equivalent circuit shown in FIG. can get. According to the equivalent circuit shown in FIG. 11, the inspection current i flows through the junction resistors R1 and R2 of the junctions J1 and J2, as in the equivalent circuit shown in FIG. The current supply unit 4 can supply inspection current to the joints J1 and J2 to be inspected by appropriately turning on and off the changeover switch SW shown in FIG.

  The potential difference V generated at the junction resistance R1 can be detected via the coupling capacitors C21 and C31, and the potential difference V generated at the junction resistance R2 can be detected via the coupling capacitors C23 and C33. As a result, the potential difference V indicating the resistance value related to the failure of the joints J1 and J2 can be detected and the failure of the joints J1 and J2 can be detected by the same processing as steps S1 to S10 shown in FIG. Becomes easy.

  In the equivalent circuit shown in FIG. 11, a coupling capacitor C is interposed in series with the current path of the inspection current i. For this reason, if a direct current is used as the inspection current i, the coupling capacitor C will block it. Therefore, it is preferable that the current supply unit 4 supplies a periodic current, such as an alternating current, whose magnitude varies periodically as the inspection current i.

  Moreover, although the board | substrate inspection apparatus 1 was provided with the 1st jig | tool 3 and the 2nd jig | tool 2, and the board | substrate inspection apparatus 1a showed the example provided with the 1st jig | tool 3a and the 2nd jig | tool 2a, the board | substrate inspection apparatus 1 was shown. The substrate inspection apparatus 1a only needs to include the detection electrodes 31, 33, 21, 23, and the first jig 3, 3a and the second jig 2, It is not restricted to the example provided with 2a.

DESCRIPTION OF SYMBOLS 1, 1a Board | substrate inspection apparatus 2, 2a 2nd jig | tool 3, 3a 1st jig | tool 4 Current supply part 5 Voltage detection part 6 Control part 11 Base material 12, 12a X electrode (set)
13 Transparent electrode (first main electrode)
14 First connection electrode 15 Second connection electrode 16, 18 Wiring 17, 19 Tab terminal 20, 30 Plate 21, 22 Detection electrode (second detection electrode)
31, 32 Detection electrode (first detection electrode)
23, 33 Detection electrode 40 Y electrode (group)
61 Determination unit 100, 100a Touch panel (substrate)
AMP amplifier circuit C, C21, C22, C23, C31, C32, C33 Coupling capacitance F Cover film i Inspection current J1, J2 Junction P Contact pin R1, R2 Junction resistance Rx Resistance V Potential difference Vref Reference voltage

Claims (12)

A substrate inspection apparatus for inspecting a substrate on which a conductive first main electrode and a conductive first connection electrode joined so as to overlap the first main electrode in the thickness direction are formed,
A first detection electrode disposed opposite to the joint on the first main electrode side than the first connection electrode in the joint between the first main electrode and the first connection electrode;
A second detection electrode disposed opposite to the joint on the first connection electrode side than the first main electrode in the joint;
A current supply for supplying current to the junction;
A substrate inspection apparatus comprising: a voltage detection unit that detects a potential difference between the first detection electrode and the second detection electrode. The substrate further includes a conductive second connection electrode joined to the first main electrode so as to be separated from the first connection electrode and overlap the first main electrode in the thickness direction,
The substrate inspection apparatus according to claim 1, wherein the current supply unit supplies a current to the bonding unit by causing a current to flow between the first connection electrode and the second connection electrode. The first main electrode extends along a predetermined first direction,
The substrate is
A second main electrode extending along a second direction intersecting the first direction and facing the first main electrode at a position intersecting the first main electrode;
A conductive second connection electrode joined to the second main electrode so as to be separated from the intersecting position and overlap the second main electrode in the thickness direction;
The substrate inspection apparatus according to claim 1, wherein the current supply unit supplies a current to the bonding unit by causing a current to flow between the first connection electrode and the second connection electrode. A plurality of sets of the first main electrode, the first connection electrode, and the joint portion are formed on the substrate,
A plurality of pairs of the first detection electrode and the second detection electrode are provided corresponding to each of the plurality of sets,
The substrate inspection apparatus includes:
A first jig for integrally holding the plurality of first detection electrodes in correspondence with the arrangement of the plurality of joints;
The board | substrate inspection apparatus of any one of Claims 1-3 further provided with the 2nd jig | tool which hold | maintains these 2nd detection electrodes integrally corresponding to arrangement | positioning of these several junction parts.   The substrate inspection apparatus according to claim 1, wherein the first main electrode and the first connection electrode are made of different materials. The substrate is a touch panel display;
The substrate inspection apparatus according to claim 1, wherein the first main electrode is a transparent electrode.   The board | substrate inspection apparatus of any one of Claims 1-6 further provided with the determination part which determines the quality of the said junction part based on the said electric potential difference detected by the said voltage detection part. The determination unit
A first determination step of determining pass / fail of the junction based on the potential difference detected by the voltage detection unit during a period in which a predetermined first current is supplied to the junction as the current by the current supply unit. When,
The quality of the junction is determined based on the potential difference detected by the voltage detection unit during a period in which the current supply unit supplies a second current in a direction opposite to the first current as the current to the junction. The board | substrate inspection apparatus of Claim 7 which performs the 2nd determination process which determines this.   The substrate inspection apparatus according to claim 1, wherein the current supply unit supplies a periodic current whose magnitude periodically varies as the current. An inspection jig attached to the substrate inspection apparatus according to claim 1,
A plurality of sets of the first main electrode, the first connection electrode, and the joint portion are formed on the substrate, and a plurality of the first detection electrodes are provided corresponding to the joint portions of the plurality of sets. And
An inspection jig for integrally holding the plurality of first detection electrodes in correspondence with the arrangement of the plurality of joints. An inspection jig attached to the substrate inspection apparatus according to claim 1,
A plurality of sets of the first main electrode, the first connection electrode, and the joint portion are formed on the substrate, and a plurality of the second detection electrodes are provided corresponding to each of the plurality of joint portions. And
An inspection jig that integrally holds the plurality of second detection electrodes in correspondence with the arrangement of the plurality of joints. A substrate inspection method for inspecting a substrate on which a conductive first main electrode and a conductive first connection electrode bonded so as to overlap the first main electrode in the thickness direction are formed,
A first detection electrode disposing step of disposing the first detection electrode opposite to the joint on the first main electrode side with respect to the first connection electrode in the joint between the first main electrode and the first connection electrode; ,
A second detection electrode placement step of placing the second detection electrode opposite to the joint on the first connection electrode side than the first main electrode in the joint;
A current supplying step for supplying a current to the joint;
A substrate inspection method including a voltage detection step of detecting a potential difference between the first detection electrode and the second detection electrode.

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