JP2013182128A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve inspection efficiency by providing a way to inspect connection reliability between IC chips, an FPC (Flexible Printed Circuit), and a display panel all together in one go and to simplify a connection inspection pattern configuration.SOLUTION: An IC chip 21 has a pair of chip-side inspection terminals 23a. 23b, and an FPC 25 has a pair of circuit-board-side inspection terminals 27a, 27b. The chip-side inspection terminals 23a, 23b are electrically interconnected and the circuit-board-side inspection terminals 27a, 27b are electrically connected to the chip-side inspection terminals 23a. 23b, respectively, via inspection wiring 14 on a terminal area 1a. Each of the pair of circuit-board-side inspection terminals 27a, 27b is electrically connected to a respective measurement connection pad 28 for measuring electrical resistance therebetween.

Description

  The present invention relates to a display device having a COG (Chip On Glass) mounting structure in which an integrated circuit (IC) chip is directly mounted on the surface of a substrate constituting a display panel, and in particular, an IC chip and a flexible printed wiring board ( The present invention relates to a technique for inspecting connection reliability for a display panel of a flexible printed circuit (FPC).

  In a display device having a COG mounting structure, an IC chip that functions as a driver is mounted on a terminal area provided at the peripheral portion of the display panel, and an FPC that supplies a signal is connected to the IC chip. It is important that the terminal area is securely connected, but in recent high-definition display devices, both the connection terminals of the IC chip and the FPC and the connection terminals on the terminal area connected to these terminals are connected. In addition, since the number is thin and the pitch between the terminals is extremely narrow, even a slight misalignment during manufacturing tends to cause a connection failure between the IC chip or the FPC and the display panel.

  Therefore, a process for inspecting the connection reliability between the IC chip or FPC and the display panel is employed, and a connection inspection pattern suitable for the inspection has been proposed.

  For example, in Patent Document 1, a connection inspection pattern provided on a terminal region of a display panel and a connection resistance are measured after mounting an IC chip (semiconductor chip) using the pattern, and an IC is determined depending on the magnitude of the connection resistance. A process of inspecting an electrical connection state between a terminal of a chip and a terminal on a display panel is disclosed.

  Further, in Patent Document 2, three dummy terminals for measuring connection resistance short-circuited to each other are provided on the terminal region of the display panel, and terminals connected to these three dummy terminals and leads extending from the respective terminals are provided. Disclosed is a connection test pattern in which terminals and four land patterns formed on the ends thereof are provided on an FPC, and a method of measuring electrical resistance by a four-terminal resistance measurement method using the test pattern. Yes.

JP 2005-209894 A Japanese Patent Laid-Open No. 06-82802

  However, the connection inspection pattern disclosed in Patent Document 1 and the inspection process using the pattern are used for independently inspecting the connection reliability of the IC chip, and the connection inspection pattern disclosed in Patent Document 2 is used. And the inspection process using this is used to independently inspect the connection reliability of the FPC. In order to inspect the connection reliability of both the driver IC chip and the FPC, for example, Since it is necessary to provide each connection inspection pattern, the number of wirings and terminals for connection inspection increases and the configuration of the connection inspection pattern becomes complicated. In addition, the step of inspecting the connection reliability of the driver IC chip and the step of inspecting the connection reliability of the FPC must be performed separately, and the number of steps increases, resulting in poor inspection efficiency.

  The present invention has been made in view of such a point, and the object of the present invention is to make it possible to inspect the connection reliability of the IC chip, the FPC, and the display panel in a lump, thereby improving the inspection efficiency and connecting. It is to simplify the configuration of the inspection pattern.

  In order to achieve the above object, the present invention devised the configuration of the connection inspection pattern so that the connection resistance between the IC chip and the display panel and the connection resistance between the FPC and the display panel can be measured at a time.

  Specifically, the present invention is directed to a display device having a COG mounting structure to which an IC chip and an FPC are connected, and the following solution is taken.

That is, the first invention is
A display panel having a terminal region at the periphery,
An IC chip and an FPC connected to the terminal area;
The terminal region has at least one electrical resistance measurement first inspection terminal connected to the IC chip on one end side and at least the other electrical resistance measurement second inspection terminal connected to the FPC on the other end side. A pair of inspection wiring is provided,
The IC chip has at least a pair of electric resistance measurement chip side inspection terminals provided corresponding to the first inspection terminals and electrically connected to the corresponding first inspection terminals,
The FPC has at least a pair of electrical resistance measurement wiring board side inspection terminals provided corresponding to the second inspection terminals and electrically connected to the corresponding second inspection terminals,
The pair of chip side inspection terminals are electrically connected to each other, and the wiring board side inspection terminals are electrically connected to the chip side inspection terminals via the inspection wiring. The side inspection terminals are electrically connected to measurement connection pads for measuring the electrical resistance between the pair of wiring board side inspection terminals.

  In the first invention, the connection structure in which the chip side inspection terminal on the IC chip and the first inspection terminal on the display panel are electrically connected, the wiring board side inspection terminal on the FPC, and the second on the display panel. A connection inspection pattern including a connection structure in which inspection terminals are electrically connected and a measurement connection pad for measuring electric resistance in both the connection structures is configured. By measuring the electrical resistance between the pair of wiring board side inspection terminals using this connection inspection pattern, the connection resistance between the chip side inspection terminal on the IC chip and the first inspection terminal on the display panel, and on the FPC The wiring board side inspection terminal and the connection resistance between the second inspection terminals on the display panel can be measured at a time. As a result, it is possible to collectively inspect the connection reliability between the IC chip and the FPC and the display panel, and to improve the inspection efficiency. Also, compared to the case where the connection test patterns for the IC chip and the FPC are separately provided, the connection reliability of the IC chip and the FPC with respect to the display panel can be inspected with one connection test pattern. The number of wirings and terminals for connection inspection can be reduced, and the configuration of the connection inspection pattern can be simplified.

A second invention is the display device of the first invention, wherein
In the terminal area, in addition to the first inspection terminal and the second inspection terminal, a plurality of chip terminals connected to the IC chip and a plurality of wiring board terminals connected to the FPC are provided. Provided,
The IC chip has a plurality of chip connection terminals that are electrically connected to the respective chip terminals, and each of the chip connection terminals and each of the chip side inspection terminals includes a bump electrode,
The FPC has a plurality of wiring board connection terminals electrically connected to the wiring board terminals.
Each of the plurality of chip connection terminals and the wiring board connection terminals is at least partially aligned along the periphery of the display panel.
The pair of chip side inspection terminals are provided separately at both end positions of a row formed by the chip connection terminals,
The pair of wiring board side inspection terminals are provided separately at both end positions of a row formed by the plurality of wiring board connection terminals.

  In the second invention, each chip connection terminal is a bump electrode. In the formation of the bump electrode, the electrode height tends to vary due to the specific conditions at both ends rather than the central side where the conditions such as the flow rate and current density of the plating solution are uniform. For this reason, the connection reliability on the both ends of the IC chip tends to decrease with respect to the display panel. In addition, the terminal for connecting the wiring board tends to be worse on the both end sides than the center side on the condition of the terminal surface when connected to the display panel. For example, when the FPC is connected to the terminal area of the display panel via an anisotropic conductive film (ACF), the FPC is pressed against the terminal area via the ACF. Such a condition tends to be non-uniform on both ends of the FPC. For this reason, the connection reliability with respect to the display panel tends to be lowered at both ends of the FPC.

  On the other hand, in the present invention, since the pair of chip side inspection terminals and the pair of wiring board side inspection terminals are provided separately at both end positions of the connection portion with respect to the display panel, both the IC chip and the FPC are attached to the display panel. The connection resistance can be measured at a location where the connection reliability is likely to decrease, and a connection failure of the IC chip or FPC to the display panel can be reliably detected.

A third invention is the display device of the first or second invention,
Two sets of the pair of chip side inspection terminals and wiring board side inspection terminals are provided,
Of the two sets of chip-side inspection terminals, each chip-side inspection terminal in one set is electrically connected to a different chip-side inspection terminal in the other set in the IC chip,
Of the two sets of wiring board side inspection terminals, the wiring board side inspection terminals in one set are electrically connected in the FPC, and each wiring board side inspection terminal in the other group is electrically connected to the measurement connection pad. It is characterized by being connected.

  In the third aspect of the invention, since two pairs of the chip side inspection terminal and the wiring board side inspection terminal are provided, the connection to be inspected as compared with the case where both of these inspection terminals are provided one by one. The inspection accuracy can be increased by the amount of the structural portion, and the connection failure of the IC chip or the FPC to the display panel can be detected more reliably.

4th invention is the display apparatus of 1st or 2nd invention,
The pair of chip side inspection terminals and the wiring board side inspection terminals are provided one by one,
The pair of chip side inspection terminals are electrically connected to each other in the IC chip.

  In the fourth aspect of the invention, since only one pair of the chip side inspection terminal and the wiring board side inspection terminal is provided, the number of inspection terminals is smaller than when a plurality of sets of both of these inspection terminals are provided. Therefore, the configuration of the connection inspection pattern can be simplified, and the connection structure for the terminal area of the IC chip and the FPC can be simplified and reduced in size.

According to a fifth invention, in any one display device of the first to fourth inventions,
The pair of wiring board side inspection terminals are electrically connected via wiring in the IC chip or in addition to the FPC,
The potential of the wiring is fixed at a predetermined level.

  In the fifth aspect of the invention, since the wiring for electrically connecting the pair of wiring side inspection terminals is fixed at a predetermined level potential, the wiring is prevented from becoming a floating line, and the FPC and the IC chip. It is possible to suppress adverse effects such as EMI (ElectroMagnetic Interference) and ESD (ElectroStatic Discharge) on a display signal supplied to the display panel via the.

A sixth invention is the display device of the fifth invention, wherein
The potential of the wiring is fixed at a ground level.

  According to the sixth aspect of the invention, the operational effects of the fifth aspect of the invention are concretely exhibited.

A seventh invention is the display device of any one of the first to sixth inventions,
The measurement connection pad is covered with an insulating film.

  In the seventh aspect of the invention, since the measurement connection pad is covered with an insulating film and insulated from the outside, it is possible to prevent a short circuit between the measurement connection pad and other components constituting the display device. Can prevent adverse effects on the display operation. In addition, corrosion of the connection pad for measurement due to moisture or the like can be prevented.

An eighth invention is the display device according to any one of the first to seventh inventions,
A housing for housing the display panel;
The FPC is connected to the edge of the terminal region and extends to the outside of the casing, and is bent so that the extension destination side is located on the back side of the casing,
The connection pad for measurement is provided on the extension destination side of the FPC so as to face the back side of the housing,
The housing is formed of an insulating resin.

  In the eighth invention, since the connection pad for measurement faces the back side of the housing, it is possible to prevent a short circuit with other components other than the housing. Furthermore, since the casing is made of an insulating resin, there is no possibility of short-circuiting with the casing even when the measurement connection pad is exposed to the outside. Therefore, it is not necessary to take measures against short circuits such as covering the measurement connection pads with an insulating film, and the number of manufacturing steps of the display device can be reduced.

A ninth invention is the display device of the fifth invention, wherein
A housing for housing the display panel;
The FPC is connected to the edge of the terminal region and extends to the outside of the casing, and is bent so that the extension destination side is located on the back side of the casing,
The connection pad for measurement is provided on the extension destination side of the FPC so as to face the back side of the housing,
The housing is made of metal, and the potential of the housing is fixed at the same level as the wiring.

  In the ninth aspect of the invention, since the measurement connection pad faces the back side of the casing, it is possible to prevent a short circuit with other parts other than the casing. In addition, the housing is made of metal and its potential is fixed at the same level as the wiring that electrically connects the pair of wiring board side inspection terminals, so that the measurement connection pad is exposed to the outside. Even if it is short-circuited with the housing, there is no electrical adverse effect on the display device. Therefore, it is not necessary to take measures against short circuits such as covering the measurement connection pads with an insulating film, and the number of manufacturing steps of the display device can be reduced.

  According to the present invention, the connection structure in which the chip side inspection terminal on the IC chip and the first inspection terminal on the display panel are electrically connected, and the wiring board side inspection terminal on the FPC and the second inspection on the display panel are connected. Since the connection inspection pattern including the connection structure in which the terminals are electrically connected is configured, the pair of inspections are performed using the measurement connection pads respectively electrically connected to the pair of wiring board side inspection terminals. By measuring the electrical resistance between the board side inspection terminals, the connection resistance between the chip side inspection terminal on the IC chip and the first inspection terminal on the display panel, the wiring board side inspection terminal on the FPC, and the display panel The connection resistance between the second inspection terminals can be measured at a time. As a result, the connection reliability between the IC chip and the FPC and the display panel can be collectively inspected, the inspection efficiency can be improved, and the configuration of the connection inspection pattern can be simplified.

FIG. 1 is a plan view schematically showing the liquid crystal display device according to the first embodiment. FIG. 2 is an exploded perspective view of the liquid crystal display device according to the first embodiment. FIG. 3 is a plan view schematically showing the configuration of the liquid crystal display module. FIG. 4 is an enlarged cross-sectional view illustrating the structure of the terminal region portion of the liquid crystal display device according to the first embodiment. FIG. 5 is a plan view schematically showing a main part of the liquid crystal display device according to the first embodiment. FIG. 6 is a plan view schematically showing a main part of a liquid crystal display device according to a modification of the first embodiment. FIG. 7 is a plan view schematically showing a main part of the liquid crystal display device according to the second embodiment. FIG. 8 is a plan view schematically showing a main part of a liquid crystal display device according to a modification of the second embodiment. FIG. 9 is a plan view schematically showing a main part of the liquid crystal display device according to the third embodiment. FIG. 10 is a plan view schematically showing a main part of a liquid crystal display device according to another embodiment. FIG. 11 is a plan view schematically showing a main part of a liquid crystal display device according to another embodiment. FIG. 12 is an enlarged cross-sectional view showing a structure of a terminal region portion of a liquid crystal display device according to another embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments.

Embodiment 1 of the Invention
In the first embodiment, a liquid crystal display device S will be described as an example of a display device according to the present invention. FIG. 1 is a plan view showing a schematic configuration of the liquid crystal display device S. FIG. FIG. 2 is an exploded perspective view of the liquid crystal display device S. FIG. FIG. 3 is a plan view showing a schematic configuration of the liquid crystal display module M. FIG. FIG. 4 is an enlarged cross-sectional view showing the structure of the terminal region 1a portion of the liquid crystal display device S.

  As shown in FIGS. 1 and 2, the liquid crystal display device S includes a liquid crystal display module M, a metal casing 7 that houses the liquid crystal display panel P that constitutes the module M, and the liquid crystal display panel P. And a metal bezel 5 formed in a frame shape so as to be disposed on the front surface and to expose the display region D. For example, the bezel 5 is fixed to the housing 7 by screws or the like. The potential of the housing 7 is fixed to the ground level by a ground wiring (not shown).

  The liquid crystal display module M supplies a display signal to the liquid crystal display panel P, an IC chip 21 that functions as a driver mounted directly on the substrate 1 constituting the liquid crystal display panel P, and the IC chip 21. The COG mounting structure includes the FPC 25.

  In the liquid crystal display panel P, as shown in FIG. 3, both outer peripheral edges of the active matrix substrate 1 and the counter substrate 2 facing each other are bonded by a frame-shaped sealing material 3. The liquid crystal layer 4 is sealed inside the sealing material 3.

  The liquid crystal display panel P includes, for example, a rectangular display area D that displays an image in an area where the active matrix substrate 1 and the counter substrate 2 overlap and inside the sealing material 3, that is, an area where the liquid crystal layer 4 is provided. Have. Further, the liquid crystal display panel P has a frame region F having a rectangular frame shape that is a non-display region around the display region D. On one side (the lower side in FIG. 3) of the frame region F, there is provided a terminal region 1a in which the active matrix substrate 1 protrudes from the counter substrate 2 and the surface of the counter substrate 2 is exposed.

  In the terminal area 1 a, the IC chip 21 is mounted near the display area D, and one end of the FPC 25 is connected to the edge side located outside the IC chip 21. As shown in FIG. 4, the IC chip 21 and the FPC 25 are connected to the terminal region 1a via an ACF 40 in which conductive particles 42 are dispersed in, for example, an insulating adhesive 41. The FPC 25 extends to the outside of the housing 7 and is bent into a curved shape so that the extending destination side wraps around the back surface side of the housing 7.

  FIG. 5 schematically shows a connection relation between the IC chip 21 and the FPC 25 in the terminal region 1a and a connection inspection pattern which is a main part of the present embodiment.

  As shown in FIG. 5, the terminal region 1a includes a plurality of wiring board terminals 15a electrically connected to the FPC 25, and a plurality of chip terminals 15b and 15c electrically connected to the IC chip 21. Is provided. The plurality of chip terminals 15b and 15c include a plurality of output terminals 15b and a plurality of input terminals 15c, respectively. The plurality of wiring board terminals 15a, the plurality of output terminals 15b, and the plurality of input terminals 15c are separated from each other in the protruding direction (vertical direction in FIG. 5) of the terminal region 1a. Are aligned along. In FIG. 5, as an example, the terminals 15a, 15b, and 15c are shown arranged in a line. However, the terminals 15a, 15b, and 15c may be arranged in a staggered manner and arranged in multiple rows. Good.

  The wiring board terminal 15a and the output terminal 15b are electrically connected via the wiring 13 on the terminal region 1a. FIG. 5 shows a state in which the wiring board terminals 15a and the output terminals 15b are connected in a one-to-one relationship, but one output terminal 15b is used to reduce the connection resistance with the FPC 25 (wiring board connection terminal 26a described later). A plurality of wiring board terminals 15a may be provided, and a common wiring board terminal 15a may be connected to two or more different output terminals 15b.

  As shown in FIG. 4, each wiring 13 is provided on the active matrix substrate 1 and covered with an insulating film 18, and one end of the wiring 13 is connected via a contact hole 18 a formed in the insulating film 18. (The left end portion in FIG. 4) is connected to the wiring board terminal 15a, and the other end portion (right end portion in FIG. 4) of the wiring 13 is connected to the chip terminal 15b.

  Each of the input terminals 15c is connected to a lead wire 11 that is led out to the terminal region 1a from a plurality of display wires (not shown) provided on the display region D. Each lead-out wiring 11 is covered with an insulating film 18 similarly to the above-described wiring 13, and a leading end of the wiring 11 through the contact hole 18 b formed in the insulating film 18 (left end in FIG. 4). Is connected to the input terminal 15c.

  In addition to the wiring board terminal 15a, chip terminals 15b and 15c, and the wiring 13, the terminal region 1a is further connected to the IC chip 21 as shown in FIG. Output side first inspection terminals 16a and 16b, and a pair of second inspection terminals 17a and 17b for electrical resistance measurement, which are electrically connected to the FPC 25, are provided. In the present embodiment, two pairs of the output side first inspection terminals 16a and 16b and the second inspection terminals 17a and 17b are provided.

  Two pairs of output side first inspection terminals 16a and 16b are provided separately at both ends of the row formed by the plurality of output terminals 15b, and the output side first inspection terminals 16a and 16b of each group are output terminals 15b. Are arranged next to each other on the extension of the row formed by In addition, two pairs of second inspection terminals 17a and 17b are also provided separately at both end positions of the row formed by the plurality of wiring board terminals 15a, and the second inspection terminals 17a and 17b of each group are for the wiring board. The terminals 15a are arranged adjacent to each other on the extension of the row.

  The first inspection terminals 16a and 16b on the output side and the second inspection terminals 17a and 17b are arranged so as to correspond to each other one by one and are electrically connected to each other via the inspection wiring 14 on the terminal region 1a. It is connected to the. The output side first inspection terminals 16a and 16b and the second inspection terminals 17a and 17b and the inspection wiring 14 are connected by the same structure as the connection structure of the wiring board terminal 15a and the output terminal 15b and the wiring 13. . That is, the inspection wiring 14 is covered with the insulating film 18, and one end of the inspection wiring 14 is connected to the output side first inspection terminals 16 a and 16 b through the contact hole 18 a formed in the insulating film 18. The other end of the inspection wiring 14 is connected to the second inspection terminals 17a and 17b.

  The IC chip 21 has a plurality of chip connection terminals 22a and 22b corresponding to the respective chip terminals 15b and 15c. The plurality of chip connection terminals 22a and 22b include a plurality of chip input terminals 22a corresponding to the output terminals 15b and a plurality of chip output terminals 22b corresponding to the input terminals 15c. The plurality of chip input terminals 22a and the plurality of chip output terminals 22b are arranged in groups along the edge of the terminal region 1a at intervals in the width direction (vertical direction in FIG. 5) of the IC chip 21. Yes.

  The plurality of chip connection terminals include not only terminals 15b and 15c aligned along the terminal region 1a but also input terminals and output terminals arranged in the width direction of IC chip 21 (vertical direction in FIG. 5). May be.

  In addition to the chip connection terminals 22a and 22b, the IC chip 21 further includes two pairs of chip input side inspection terminals 23a and 23b for measuring electrical resistance corresponding to the output side first inspection terminals 16a and 16b. A set is provided. Of these two sets of chip input side inspection terminals 23a, 23b, a pair of chip input side inspection terminals 23a, 23b in one set is inspected in the IC chip 21 to other sets of adjacent chip input side inspection terminals 23a, 23b. It is electrically connected via the wiring 24a.

  The chip connection terminals 22a and 22b are connected to the corresponding chip terminals 15b and 15c, and the chip input side inspection terminals 23a and 23b are connected to the corresponding output side first inspection terminals 16a and 16b. Are electrically connected to each other (see FIG. 4).

  In this embodiment, the adjacent chip input side inspection terminals 23a and 23b are connected to each other via the inspection wiring 24a in the IC chip 21, but the adjacent chip input side inspection terminals 23a and 23b are connected to each other. The IC chip 21 may be electrically connected via the inspection wiring 24a formed on the surface (for example, the bottom surface).

  On the other hand, the FPC 25 has a plurality of wiring board connection terminals 26a corresponding to the respective wiring board terminals 15a. The plurality of wiring board connection terminals 26 a are aligned along the edge of the terminal region 1 a and are electrically connected to an external circuit (not shown) via the wiring 29 provided in the FPC 25.

  In addition to the wiring board connection terminal 26a, the FPC 25 further includes two sets of wiring board side inspection terminals 27a and 27b for measuring electrical resistance corresponding to each of the second inspection terminals 17a and 17b. A pair of measurement connection pads for measuring electrical resistance in a connection test pattern including the wiring board side test terminals 27a and 27b, the test terminals 16a, 16b, 17a, 17b, 23a and 23b, and the test wirings 14 and 24. 28 and a ground pad 36 are provided.

  Among the two sets of wiring board side inspection terminals 27a and 27b, the wiring board side inspection terminals 27a and 27b in one set located inside the row formed by the wiring board connection terminals 26a are connected to each other via the inspection wiring 30 on the FPC 25. Electrically connected. A ground wiring 35 is connected to the inspection wiring 30 and its potential is fixed at the ground level. Thereby, the wirings 14, 24, 30, 31 of the connection inspection pattern including the inspection wiring 30 are prevented from becoming floating lines, and the display is supplied to the liquid crystal display panel P via the FPC 25 and the IC chip 21. It is possible to suppress adverse effects such as EMI and ESD on the signal. The ground wiring 35 is connected to the ground pad 36 and is also electrically connected to the IC chip 21 via the wiring board connection terminal 26a, the wiring board terminal 15a, the wiring 13 and the chip terminal 15b. Yes.

  Further, each of the wiring board side inspection terminals 27a and 27b in the other group located outside the chip of the one set of wiring board side inspection terminals 27a and 27b is connected to a separate measurement connection via the lead wiring 31 on the FPC 25. It is electrically connected to the pad 28. As shown in FIG. 4, each measurement connection pad 28 is formed on the extending side of the FPC 25 so as to face the rear surface side of the housing 7, and has a configuration that prevents short-circuiting with other parts other than the housing 7. It is taken and exposed to the outside. Since each of these measurement connection pads 28 is electrically connected to the ground wiring 35 and its potential is fixed at the ground level, it is short-circuited to the metal casing 7 that is at the same potential in a bare state. However, there is no electrical adverse effect on the liquid crystal display device S.

  As described above, the liquid crystal display module M of the present embodiment has a connection in which the chip input side inspection terminals 23a and 23b on the IC chip 21 and the first inspection terminals 16a and 16b on the terminal region 1a are electrically connected. And four connection structures in which the wiring board side inspection terminals 27a and 27b on the FPC 25 and the second inspection terminals 17a and 17b on the liquid crystal display panel P are electrically connected. A connection inspection pattern including a pair of measurement connection pads 28 for measuring the electrical resistance is formed.

  In the case of manufacturing the liquid crystal display device S having the above-described configuration, the IC chip 21 and the FPC 25 are connected to the terminal region 1a of the liquid crystal display panel P through the ACF 40 by thermocompression bonding using a known tool. After configuring M, the connection resistance inspection of the IC chip 21 and the FPC 25 with respect to the liquid crystal display panel P is performed.

  In the connection resistance test, a known electrical resistance measuring device is used to measure the electrical resistance between one measurement connection pad 28 and the ground pad 36 of the pair of measurement connection pads 28 and the other measurement connection pad 28. By measuring the electric resistance between the wiring board side inspection terminals 27a and 27b and the connection resistances of the four chip input side inspection terminals 23a and 23b and the inspection resistances, respectively, The sum of the wiring resistances of the wirings 14, 24, 30 and the lead wiring 31 is measured.

  At this time, if an electrical resistance value higher than a predetermined electrical resistance value is measured, it is determined that a connection failure has occurred in either the IC chip 21 or the FPC 25, and an inspection for specifying the connection failure portion is performed. The liquid crystal display module M is introduced into the process. On the other hand, when an electrical resistance value equal to or lower than a predetermined electrical resistance value is measured, it is determined that both the IC chip 21 and the FPC 25 are connected to the liquid crystal display panel P in a good and reliable manner, and thereafter the liquid crystal display module The liquid crystal display device S is completed by combining M with the casing 7 and the bezel 5.

-Effect of Embodiment 1-
According to the first embodiment, the connection resistance between the chip input side inspection terminals 23a and 23b on the IC chip 21 and the first inspection terminals 16a and 16b on the terminal region 1a, and the wiring board side inspection terminals 27a and 27b on the FPC 25. In addition, the connection resistance between the second inspection terminals 17a and 17b on the terminal region 1a can be measured at a time. Thereby, it is possible to collectively inspect the connection reliability between the IC chip 21 and the FPC 25 and the liquid crystal display panel P, thereby improving the inspection efficiency and simplifying the configuration of the connection inspection pattern. Can do.

  In addition, in this embodiment, since two pairs of the chip input side inspection terminals 23a and 23b and the wiring board side inspection terminals 27a and 27b are provided, one set of these inspection terminals 23a, 23b, 27a and 27b. Compared with the case where only one is provided, the inspection accuracy can be increased by the amount of connection structure portions to be inspected, and the connection failure of the IC chip 21 or the FPC 25 to the liquid crystal display panel P can be reliably detected.

  Further, since the measurement connection pad 28 and the ground pad 36 are provided on the FPC 25, the connection resistance inspection can be performed together with the so-called lighting inspection for inspecting the state of the image display, and the inspection process can be made more efficient. Can be planned.

<< Modification of Embodiment 1 >>
FIG. 6 is a plan view schematically showing a connection inspection pattern according to this modification.

  In this modification, as shown in FIG. 6, in addition to the output side first inspection terminals 16a and 16b of the first embodiment, two pairs of input side first inspection terminals 16a and 16b are further provided. Two sets of these input side first inspection terminals 16a and 16b are arranged adjacent to each other on the extension of the row formed by the input terminal 15c. Of these two sets of input side first inspection terminals 16a, 16b, each input side first inspection terminal 16a, 16b in one set is connected to the other input side first inspection terminals 16a, 16b in the terminal region 1a. It is electrically connected via the provided inspection wiring 19.

  Further, the IC chip 21 is further provided with two pairs of chip output side inspection terminals 23a and 23b in addition to the chip input side inspection terminals 23a and 23b of the first embodiment. These chip output side inspection terminals 23a and 23b are provided at positions corresponding to the respective input side first inspection terminals 16a and 16b, and the corresponding input side first inspection terminals 16a and 16b are respectively connected via the conductive particles 42 in the ACF 40. Are electrically connected.

  In the first embodiment, the adjacent chip input side inspection terminals 23a and 23b are connected to each other via the inspection wiring 24a. However, in the present modification, each of the chip input side inspection terminals 23a and 23b corresponds. The chip output side inspection terminals 23a and 23b are electrically connected in a one-to-one manner within the IC chip 21 via the inspection wiring 24b.

−Effect of Modification of Embodiment 1−
According to this modification, since the connection inspection can be performed at the four corners of the IC chip 21, the connection of the IC chip 21 to the terminal region 1a due to the inclination of the terminal region 1a in the protruding direction (vertical direction in FIG. 6) or the like. Defects can be detected accurately, and the accuracy of defect detection in connection resistance inspection can be increased. In addition, the same effects as those of the first embodiment can be obtained.

<< Embodiment 2 of the Invention >>
FIG. 7 is a plan view schematically showing a connection inspection pattern according to the second embodiment. In each of the following embodiments, the configuration of the connection test pattern is the same as that of the first embodiment except for the configuration of the liquid crystal display device S except for the configuration of the connection test pattern. Only the same components will be described in the description of the first embodiment based on FIGS. 1 to 5, and the detailed description thereof will be omitted.

  In the first embodiment, two pairs of output side first inspection terminals 16a, 16b and a pair of second inspection terminals 17a, 17b are provided, and a pair of chip input side inspection terminals 23a, 23b and Although two pairs of wiring board side inspection terminals 27a and 27b are also provided, in this embodiment, as shown in FIG. 7, a pair of output side first inspection terminals 16a and 16b and a pair of second inspection terminals are provided. Only one pair of inspection terminals 17a and 17b is provided, and correspondingly, a pair of chip input side inspection terminals 23a and 23b and a pair of wiring board side inspection terminals 27a and 27b are also provided.

  The pair of first output terminals 16a and 16b on the output side are positioned at both ends of the row formed by the output terminal 15b, and the pair of second test terminals 17a and 17b are positioned at both ends of the row formed by the wiring board connection terminal 26a. The input side inspection terminals 23a and 23b are arranged separately at both end positions of the row formed by the chip input terminals 22a, and the pair of wiring board side inspection terminals 27a and 27b are arranged separately at both end positions of the row formed by the wiring board connection terminals 26a. Yes.

  The pair of chip input side inspection terminals 23a and 23b are electrically connected to each other through the inspection wiring 24c in the IC chip 21. The inspection wiring 24c is electrically connected to the ground wiring 35 through the chip connection terminal 22a, the output terminal 15b, the wiring 13, the wiring board terminal 15a, and the wiring board connection terminal 26a, and the potential thereof is at the ground level. It is fixed.

  In the present embodiment, the pair of chip input side inspection terminals 23 a and 23 b are connected to each other in the IC chip 21, but the pair of chip input side inspection terminals 23 a and 23 b are connected to the surface of the IC chip 21. It may be electrically connected via an inspection wiring 24c formed on (for example, the bottom surface).

-Effect of Embodiment 2-
According to the second embodiment, only one pair of the chip input side inspection terminals 23a and 23b and the wiring board side inspection terminals 27a and 27b is provided, so that a plurality of these inspection terminals 23a, 23b, 27a and 27b are provided. Compared with the case where the set is provided, the configuration of the connection inspection pattern can be simplified by the amount of inspection terminals, and the connection structure of the IC chip 21 and the FPC 25 to the terminal region 1a is simplified and reduced in size. be able to.

<< Modification of Embodiment 2 >>
FIG. 8 is a plan view schematically showing a connection inspection pattern according to this modification.

  In this modification, as shown in FIG. 8, in addition to the output side first inspection terminals 16a and 16b of the second embodiment, a pair of input side first inspection terminals 16a and 16b is further provided. The pair of input side first inspection terminals 16a and 16b are provided separately at both end positions of the row formed by the input terminal 15c, and are arranged on the extension of the row. The pair of input side first inspection terminals 16a and 16b are electrically connected to each other via the inspection wiring 20 provided in the terminal region 1a. The inspection wiring 20 is electrically connected to the ground wiring 35 through the input terminal 15c, the chip output terminal 22b, the wiring 24d, the chip input terminal 22a, the output terminal 15b, the wiring 13, the wiring board terminal 15a, and the wiring board connection terminal 26a. The potential is fixed at the ground level.

  In addition to the chip input side inspection terminals 23a and 23b of the first embodiment, the IC chip 21 is further provided with a pair of chip output side inspection terminals 23a and 23b. These chip output side inspection terminals 23a and 23b are provided at positions corresponding to the respective input side first inspection terminals 16a and 16b, and the corresponding input side first inspection terminals 16a and 16b are respectively connected via the conductive particles 42 in the ACF 40. Are electrically connected.

  In the second embodiment, the pair of chip input side inspection terminals 23a and 23b are connected to each other via the inspection wiring 24c. However, in this modification, each of the chip input side inspection terminals 23a and 23b corresponds. The chip output side inspection terminals 23a and 23b are electrically connected in a one-to-one manner within the IC chip 21 via the inspection wiring 24b.

−Effect of Modification of Embodiment 2−
According to this modification, since the connection inspection can be performed at the four corners of the IC chip 21, the connection of the IC chip 21 to the terminal region 1a due to the inclination of the terminal region 1a in the protruding direction (vertical direction in FIG. 8) or the like. Defects can be detected accurately, and the accuracy of defect detection in connection resistance inspection can be increased. In addition, the same effects as those of the second embodiment can be obtained.

<< Embodiment 3 of the Invention >>
FIG. 9 is a plan view schematically showing a connection inspection pattern according to the third embodiment.

  In the first and second embodiments, the pair of measurement connection pads 28 and the ground pad 36 are provided on the FPC 25. However, in the present embodiment, as shown in FIG. 9, a circuit board separate from the FPC 25 is provided. A pair of measurement connection pads 53 and a ground pad 55 are provided on 50.

  The front end portion of the FPC 25 opposite to the connection side of the liquid crystal display panel P is disposed at the outermost positions in the row formed by the wiring board connection terminals 26a of the two sets of wiring board side inspection terminals 27a and 27b. A pair of wiring board connection terminals 27 c to which the respective wiring board side inspection terminals 27 a and 27 b are connected via the wiring 29 and a wiring board connection terminal 27 c to which the ground wiring 35 is connected are provided. The end portions of the FPC 25 provided with these wiring board connection terminals 27 c are connected to the connectors 51 on the circuit board 50, so that the wiring board connection terminals 27 c are connected to the terminals 52 in the connector 51. The measurement connection pads 53 and the ground pads 55 provided on the circuit board 50 are connected to each other.

-Effect of Embodiment 3-
According to the third embodiment, the connection reliability between the circuit board 50 and the FPC 25 can be inspected together with the inspection of the connection reliability of the IC chip 21 and the FPC 25 with respect to the liquid crystal display panel P. Can be achieved.

<< Other Embodiments >>
10 and 11 are plan views schematically showing connection inspection patterns according to other embodiments.

  In the first to third embodiments and the modifications thereof, the inspection terminals 23a, 23b, 27a, and 27b are provided on both end sides along the panel edge of the IC chip and on both end sides along the panel edge of the FPC, and connection inspection is performed. Although the configuration in which the use pattern is routed has been described, the present invention is not limited to this. For example, as another embodiment, as shown in FIGS. 10 and 11, the inspection terminals 23a, 23b, 27a, 27b are provided only on one side along the panel edge of the IC chip 21 and on one side along the panel edge of the FPC 25. May be provided so that the connection inspection pattern is routed.

  FIG. 12 is an enlarged sectional view showing the structure of the terminal region 1a portion of the liquid crystal display device S according to another embodiment.

  In the first embodiment, the measurement connection pad 28 is formed on the back side of the FPC 25 so as to face the back side of the housing 7 and is exposed to the outside. However, the present invention is not limited to this. For example, each measurement connection pad 28 is provided on the front surface side of the FPC 25 and is connected to the wiring on the back surface side of the FPC through a through hole (not shown) formed in the FPC 25, and the opposite side of the housing 7 is connected to the measurement connection pad 28. It is suitable. Each measuring connection pad 28 is entirely covered with an insulating tape which is an insulating film.

  Even with such a configuration, each measurement connection pad 28 is covered with the insulating tape 60 and insulated from the outside, so that a short circuit between the measurement connection pad 28 and other components constituting the liquid crystal display device S is prevented. It is possible to prevent an adverse effect on the display operation due to the short circuit. Further, corrosion of the measurement connection pad 28 due to moisture or the like can be prevented.

  In the first embodiment, the metal casing 7 and the measurement connection pad 28 are set to the same potential, so that the liquid crystal display device is electrically connected even if the casing 7 and the measurement connection pad 28 are short-circuited. However, the present invention is not limited to this, and the housing 7 may be simply made of resin.

  Even with such a configuration, it is possible to prevent a short circuit with other parts other than the housing 7 and, in addition, a short circuit with the resin housing 7 even when the measurement connection pad 28 is exposed to the outside. Therefore, it is not necessary to take measures against short-circuiting such as covering the measurement connection pad 28 with an insulating film, so that the number of manufacturing steps of the liquid crystal display device S can be reduced.

  As mentioned above, although preferable embodiment of this invention was described, the technical scope of this invention is not limited to the range as described in each said embodiment. It is understood by those skilled in the art that the above embodiments are examples, and that various modifications can be made to the combinations of the respective constituent elements and processing processes, and such modifications are within the scope of the present invention. It is a place.

  For example, in each of the above embodiments, the liquid crystal display device S has been described as an example. However, the present invention is not limited to this, and other display devices such as an organic EL (Electro Luminescence) display device and a plasma display device can be used. The present invention can also be applied if it has a structure in which an IC chip and an FPC are connected to a display panel.

  As described above, the present invention is useful for a display device having a COG mounting structure in which an IC chip and an FPC are mounted. In particular, the connection reliability between the IC chip and the FPC and the display panel can be collectively checked. Therefore, it is suitable for a display device that is desired to improve the inspection efficiency and simplify the configuration of the connection inspection pattern.

P liquid crystal display panel S liquid crystal display device 1a terminal area 7 housing 15a wiring board terminal 15b, 15c chip terminal 21 IC chip 16a, 16b output side first inspection terminal, input side first inspection terminal (first inspection terminal)
14, 19, 20, 24a, 24b, 24c, 30 Inspection wiring 17a, 17b Second inspection terminal 22a Chip input terminal (chip connection terminal)
22b Chip output terminal (chip connection terminal)
23a, 23b Chip input side inspection terminal, Chip output side inspection terminal (chip side inspection terminal)
25 FPC
26a Wiring board connection terminals 27a, 27b Wiring board side inspection terminals 28 Measuring connection pads 60 Insulating tape (insulating film)

Claims (9)

A display panel having a terminal region at the periphery,
An integrated circuit chip connected to the terminal region and a flexible printed wiring board;
In the terminal area, a first inspection terminal for measuring electrical resistance connected to the integrated circuit chip is on one end side, and a second testing terminal for measuring electrical resistance connected to the flexible printed wiring board is on the other end side. Provided with at least a pair of inspection wirings, respectively,
The integrated circuit chip has at least a pair of chip-side inspection terminals for measuring electrical resistance that are provided corresponding to the first inspection terminals and are electrically connected to the corresponding first inspection terminals.
The flexible printed wiring board includes at least a pair of wiring board side inspection terminals for measuring electrical resistance, which are provided corresponding to the second inspection terminals and are electrically connected to the corresponding second inspection terminals. And
The pair of chip side inspection terminals are electrically connected to each other, and the wiring board side inspection terminals are electrically connected to the chip side inspection terminals via the inspection wiring. A display device, wherein a connection pad for measurement for measuring electrical resistance between the pair of wiring board side inspection terminals is electrically connected to the side inspection terminals. The display device according to claim 1,
In the terminal area, in addition to the first inspection terminal and the second inspection terminal, a plurality of chip terminals connected to the integrated circuit chip and a plurality of wiring boards connected to the flexible printed wiring board Terminals are provided,
The integrated circuit chip has a plurality of chip connection terminals that are electrically connected to the respective chip terminals, and each of the chip connection terminals and each of the chip side inspection terminals includes a bump electrode,
The flexible printed wiring board has a plurality of wiring board connection terminals electrically connected to the wiring board terminals.
Each of the plurality of chip connection terminals and the wiring board connection terminals is at least partially aligned along the periphery of the display panel.
The pair of chip side inspection terminals are provided separately at both end positions of a row formed by the chip connection terminals,
The display device according to claim 1, wherein the pair of wiring board side inspection terminals are provided separately at both end positions of a row formed by the wiring board connection terminals. The display device according to claim 1 or 2,
The above-mentioned pair of chip side inspection terminals and wiring board side inspection terminals are provided in two sets,
Of the two sets of chip-side inspection terminals, each chip-side inspection terminal in one set is electrically connected to a different chip-side inspection terminal in the other set in the integrated circuit chip,
Of the two sets of wiring board side inspection terminals, the wiring board side inspection terminals in one set are electrically connected to each other in the flexible printed wiring board, and each wiring board side inspection terminal in the other set is connected to the measurement. A display device which is electrically connected to a pad. The display device according to claim 1 or 2,
The pair of chip side inspection terminals and the wiring board side inspection terminals are provided one by one,
The display device, wherein the pair of chip side inspection terminals are electrically connected to each other in the integrated circuit chip. The display device according to any one of claims 1 to 4,
The pair of wiring board side inspection terminals are electrically connected via wiring in the integrated circuit chip or in addition to the flexible printed wiring board,
A display device, wherein the potential of the wiring is fixed at a predetermined level. The display device according to claim 5,
A display device, wherein the potential of the wiring is fixed to a ground level. The display device according to any one of claims 1 to 6,
The display device, wherein the measurement connection pad is covered with an insulating film. The display device according to any one of claims 1 to 7,
A housing for housing the display panel;
The flexible printed wiring board is connected to the edge of the terminal region and extends to the outside of the casing, and is bent so that the extension destination side is located on the back side of the casing,
The connection pad for measurement is provided on the extending side of the flexible printed wiring board so as to face the back side of the housing,
The display device is characterized in that the housing is formed of an insulating resin. The display device according to claim 5,
A housing for housing the display panel;
The flexible printed wiring board is connected to the edge of the terminal region and extends to the outside of the casing, and is bent so that the extension destination side is located on the back side of the casing,
The connection pad for measurement is provided on the extending side of the flexible printed wiring board so as to face the back side of the housing,
The display device characterized in that the housing is made of metal, and the potential of the housing is fixed at the same level as the wiring.

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