JP2018049196A - Display and driving circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the amount of deformation of a TFT substrate or a driving circuit board when a driver IC is mounted on one of the substrates to prevent a reduction in display quality and prevent a reduction in reliability of the product.SOLUTION: A display includes a first substrate 100 on which a driver IC 40 is mounted. The driver IC 40 is mounted with an anisotropic conductive film therebetween, and the first substrate 100 has a concave part 60 in the vicinity of a short side of the driver IC 40.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a structure for preventing deformation of a substrate due to stress when a driver IC is mounted on a display device or a drive circuit substrate.

  A liquid crystal display device or an organic EL display device uses a driver IC as a drive circuit. The driver IC may be directly mounted on a substrate such as a liquid crystal display device or may be mounted via a drive circuit substrate or the like. In a liquid crystal display device or an organic EL display device, a TFT substrate on which TFTs, pixel electrodes, and the like are conventionally formed of glass, but in order to make the display device flexible, the TFT substrate is made of a resin such as polyimide. Sometimes it forms.

  In any case, since the thermal expansion coefficient differs between the driver IC and the TFT substrate or the drive circuit substrate, stress is applied to the substrate and the driver IC near the connection portion of the driver IC, and cracks in the substrate or the driver IC Causes warping deformation.

  In Patent Document 1, in order to prevent cracks from being formed on the TFT substrate when various components are mounted on the TFT substrate formed of glass, a groove or the like is formed in advance on the back side of the TFT substrate. The structure for absorbing the stress applied to the glass at the groove portion is described.

  In Patent Document 2, when a driver IC is mounted on a TFT substrate, a cavity is formed inside the TFT substrate formed of glass in order to relieve stress applied to the TFT substrate at the connection portion of the driver IC. A configuration is described in which stress is absorbed by the cavity.

JP 2010-72380 A JP 2010-14996 A

  Liquid crystal display devices and organic EL display devices are required to have a small thickness. In these display devices, it is the thickness of the TFT substrate formed of glass or the counter substrate that greatly affects the thickness. The glass substrate is usually standardized to about 0.7 mm or 0.5 mm. However, in order to make the display device thin, the TFT substrate or the counter substrate is polished to about 0.2 mm or 0.1 mm. Further, in order to make the display device thin and flexible, a TFT substrate or the like may be formed of a resin such as polyimide.

  Either the glass substrate or the resin substrate has a thermal expansion coefficient different from that of the driver IC. The driver IC is thermocompression bonded to the TFT substrate using an anisotropic conductive film (ACF). Then, the temperature of the driver IC rises more, and the amount of thermal expansion of the driver IC becomes larger than the amount of thermal expansion of the TFT substrate. Then, when the temperature of the driver IC returns to room temperature, there arises a problem that the TFT substrate is deformed due to the generated stress.

  The deformation of the substrate itself is a problem, but if the driver IC is mounted near the display area, the influence of the deformation of the TFT substrate extends to the display area, causing unevenness of color or brightness of the display area. Become. This problem is likely to occur especially when the thickness of the TFT substrate is reduced. Further, since the drive circuit board is made of resin and has a thickness of about 30 μm, the amount of deformation when the driver IC is mounted becomes large. If it does so, the fall of the manufacturing yield and the reliability fall by the deformation | transformation of a product will become a problem.

  An object of the present invention is to prevent deterioration in display quality and product reliability by reducing the deformation amount of a substrate when a driver IC is mounted on a TFT substrate or a drive circuit substrate.

  (1) A display device having a first substrate on which a display region and a terminal portion are formed, wherein a driver IC having a long side and a short side is mounted on the terminal portion via an anisotropic conductive film, A display area, wherein a concave portion is formed in the first substrate corresponding to the short side of the driver IC.

  (2) A drive circuit board on which a driver IC connected to a display device is mounted, the driver IC having a long side and a short side, and connected to the drive circuit board via an anisotropic conductive film. In addition, a concave portion is formed in the drive circuit board corresponding to the short side of the driver IC.

3 is a plan view of the display device in Embodiment 1. FIG. It is sectional drawing which shows a thermocompression bonding process. It is a temperature profile in a thermocompression bonding process. It is sectional drawing which shows the process of thermocompression bonding when the present Example is not applied. FIG. 3 is a cross-sectional view showing a part of the thermocompression bonding process in Example 1. 6 is a cross-sectional view showing a part of a thermocompression bonding process in another example of Example 1. FIG. It is a top view which shows the state in which driver IC was connected to the TFT substrate. It is a figure which shows the comparison of the stress by thermocompression bonding in A1 thru | or A5 shown in FIG. It is a top view which shows the other example of a present Example. It is sectional drawing which shows the example of the depth of a recessed part. FIG. 3 is a diagram illustrating a relationship between a TFT substrate, a driver IC, and an ACF in Example 1. FIG. 6 is a diagram showing a relationship among a TFT substrate, a driver IC, and an ACF in another example of Example 1. It is a top view which shows the other example of a present Example. It is a top view which shows the other example of a present Example. It is a top view which shows the other example of a present Example. 6 is a plan view of a display device in Example 2. FIG. It is BB sectional drawing of FIG. 6 is a plan view of a display device in Example 3. FIG. 10 is a plan view of a display device in Example 4. FIG. It is CC sectional drawing of FIG.

  Hereinafter, the contents of the present invention will be described in detail by way of examples.

  FIG. 1 is a plan view of a liquid crystal display device according to this embodiment. In FIG. 1, the TFT substrate 100 and the counter substrate 200 are disposed to face each other, and the liquid crystal is sandwiched between the TFT substrate 100 and the counter substrate 200.

  Hereinafter, in the embodiment, the short side direction of the display device is a first direction X, a direction perpendicular to the first direction X is a second direction Y, and a direction perpendicular to the first direction X and the second direction Y is a third direction. Let it be direction Z. In this embodiment, the positive direction in the third direction Z or the direction from the TFT substrate 100 toward the counter substrate 200 is set as the upper or upper side, and the negative direction in the third direction Z or the counter substrate 200 to the TFT substrate is set. The direction toward 100 is the lower or lower side.

  As shown in FIG. 1, the liquid crystal display device has a display area 10 and a peripheral area 20. A sealing material for bonding the TFT substrate 100 and the counter substrate 200 is disposed in the peripheral region 20, and liquid crystal is sealed in a region surrounded by the sealing material. In the display region 10, pixels having pixel electrodes and TFTs (Thin Film Transistors) are formed in a matrix.

  The TFT substrate 100 is formed larger than the counter substrate 200, and the terminal portion 30 is formed in a portion where the TFT substrate 100 does not overlap the counter substrate 200. A driver IC 40 that supplies a video signal or the like is mounted on the terminal unit 30. The terminal unit 30 is connected to a drive circuit board 80 for supplying signals and power from the outside to the liquid crystal display device. In the TFT substrate 100, a recess 60 is formed at a position corresponding to an end portion in the first direction X of the driver IC 40, that is, at a short side position of the driver IC 40. In the example shown in FIG. 1, the recess 60 is formed at a position overlapping the driver IC 40. The recess 60 is for relaxing the stress generated when the driver IC 40 and the TFT substrate 100 are connected to prevent the TFT substrate 100 from being deformed.

  FIG. 2 is a cross-sectional view showing a state where the driver IC 40 is connected to the terminal portion 30 of the TFT substrate 100 by thermocompression bonding.

  The liquid crystal display device is placed on the cradle 1200, and the terminal unit 30 is placed on the backup stage 1100. In this state, pressure is applied to the pressure bonding head 1000 in the direction of the arrow, and at the same time, the driver IC 40 is heated to about 150 ° C. by the pressure bonding head 1000. Thermocompression bonding is performed via an anisotropic conductive film (ACF). When the ACF cools and reaches a certain temperature, the ACF is cured and the driver IC and the TFT substrate are bonded.

  FIG. 3 shows an example of the temperature change of the upper surface of the driver IC in thermocompression bonding. In FIG. 3, the horizontal axis represents time, and the vertical axis represents the temperature of the upper surface of the driver IC. In FIG. 3, the upper surface of the driver IC reaches 150 ° C. 12 seconds after the pressing head is pressed. At this time, the ACF is softened, and the terminals formed on the TFT substrate and the bumps of the driver IC are electrically connected by the conductive particles in the ACF. Thereafter, when the pressure bonding head is released, the driver IC is cooled, and in the course of cooling, the ACF is cured and the driver IC and the substrate are physically bonded. At this time, stress is generated at the bonding portion between the driver IC and the TFT substrate.

  FIG. 4 is a cross-sectional view showing a process of thermocompression bonding a driver IC to a liquid crystal display device to which this embodiment is not applied. FIG. 4 is a cross-sectional view of the terminal portion 30 when the liquid crystal display panel is viewed from the drive circuit board 80 side. In FIG. 4A, the ACF 50 is disposed on the terminal portion 30 of the TFT substrate 100, and the driver IC 40 is disposed thereon. The bumps 41 of the driver IC 40 are aligned so as to correspond to the terminals formed on the TFT substrate 100. In the following description, it is assumed that the linear expansion coefficient of the driver IC 40 is 3.53 × 10 −6 / ° C. and the linear expansion coefficient of the TFT substrate 100 is 3.80 × 10 −6 / ° C.

  FIG. 4B is a cross-sectional view showing a state in which the driver IC 40 is thermocompression-bonded by the pressure-bonding head 1000 via a buffer sheet 1010 formed of Teflon (registered trademark) or the like on the driver IC40. Since the driver IC is heated to about 150 ° C., the amount of thermal expansion is large, for example, δa. On the other hand, although the TFT substrate 100 also expands, the temperature does not rise as much as the driver IC 40 on the TFT substrate 100 side, so the thermal expansion amount is δb. The arrows shown in FIG. 4B indicate the direction and amount of thermal expansion of the driver IC 40 or the TFT substrate 100. The ACF 50 softens as the temperature rises, cures as the temperature falls, and bonds the driver IC 40 and the TFT substrate 100 together.

  FIG. 4C is a cross-sectional view showing a comparison between the amount of strain received by the driver IC 40 and the amount of strain received by the TFT substrate 100 at the temperature at which the ACF 50 is cured. The arrows shown in FIG. 4C indicate the direction and amount in which the driver IC 40 or the TFT substrate 100 contracts until the ACF 50 is cured. At the time when the ACF 50 is cured, the driver IC 40 remains strained by δC with respect to the TFT substrate 100. Due to this distortion, the TFT substrate 100 is bent by z1 as shown in FIG.

  When such a curvature occurs, there may be a problem in dimensions when it is incorporated into a liquid crystal display device. Further, when the TFT substrate 100 is distorted, the distortion affects the display area, and local color unevenness or luminance unevenness occurs.

  FIG. 5 is a cross-sectional view showing a part of the process of thermocompression bonding the driver IC to the liquid crystal display panel to which this embodiment is applied. FIG. 5A is a cross-sectional view in which the ACF 50 and the driver IC 40 are arranged on the terminal portion of the TFT substrate 100. 5A differs from FIG. 4A in that a recess 60 is formed in the TFT substrate 100 at a position corresponding to the end of the driver IC 40. FIG. The driver IC 40 is connected to the TFT substrate 100 by thermocompression bonding as described with reference to FIG.

  FIG. 5B is a cross-sectional view showing the state after the driver IC 40 is thermocompression bonded. The TFT substrate 100 bends due to the difference in thermal expansion due to the difference between the temperature of the driver IC 40 and the temperature of the TFT substrate 100 at the time of thermocompression bonding, but the bend amount z2 is smaller than the bend amount z1 shown in FIG. It is suppressed to such an extent that there is no problem in assembling the liquid crystal display device, or local luminance unevenness and color unevenness do not occur in the display area.

  FIG. 6 is a cross-sectional view showing a part of a process of thermocompression bonding a driver IC to a liquid crystal display panel to which another example of this embodiment is applied. FIG. 6A is a cross-sectional view in which the ACF 50 and the driver IC 40 are arranged on the terminal portion of the TFT substrate 100. 6A differs from FIG. 5A in that a through hole 70 is formed in the TFT substrate 100 corresponding to the end of the driver IC 40. FIG. The driver IC 40 is connected to the TFT substrate 100 by thermocompression bonding as described with reference to FIG.

  FIG. 6B is a cross-sectional view showing the state after the driver IC 40 is thermocompression bonded. The TFT substrate 100 bends due to the difference in thermal expansion caused by the temperature difference between the driver IC 40 and the TFT substrate 100 at the time of thermocompression bonding, but the bend amount z3 is smaller than the bend amount z1 shown in FIG. Furthermore, it is smaller than the deflection amount z2 shown in FIG. This is because the through hole 70 has a greater stress release effect.

  The recess 60 in FIG. 5 and the through hole 70 in FIG. 6 can be formed by laser irradiation or etching. In the case of the glass substrate 100, a laser having a wavelength absorbed by the glass is irradiated while focusing on a portion where the recess 60 or the through hole 70 is formed, and the glass is evaporated in this portion. Moreover, the recessed part 60 or the through-hole 70 can be formed by etching only a required part using photolithography. Generally, after the liquid crystal display panel is completed, the recess 60 or the through hole 70 is formed before the driver IC 40 is connected.

  This is basically the same when the substrate is not glass but resin. That is, a recess or a through hole can be formed in the resin substrate by laser irradiation or photolithography.

  FIG. 7 is a plan view showing a state where the driver IC 40 is connected to the TFT substrate 100. 7 shows a plan view of one side from the center of the liquid crystal display panel. The stress due to thermocompression increases at the end of the driver IC 40 in the first direction X. FIG. 7A is a plan view of a terminal portion to which this embodiment is not applied. In FIG. 7A, ½ of the long side length of the driver IC 40 is 10.11 mm, and the short side length is 1.467 mm. The width of the terminal portion 30 in the second direction Y is 3.335 mm. The upper side of FIG. 7A is the side where the counter substrate is disposed, and the driver IC 40 is disposed at a distance of 0.4 mm from the end of the counter substrate. The dimensions and position of the driver IC 40, the dimensions of the terminal portion 30, and the like are the same in FIGS. 7B to 7E. In FIG. 7A, after the driver IC 40 is thermocompression bonded, the point at which the stress appears most in the TFT substrate 100 is A1 corresponding to the corner portion of the driver IC 40.

  FIG. 7B is a plan view of a terminal portion to which this embodiment is applied. A difference from FIG. 7A is that a recess 60 is formed in the TFT substrate 100 in the vicinity of the short side of the driver IC 40. The recess 60 has a dimension of 2.157 in the second direction Y and 1.0 mm in the first direction X. The depth of the recess 60 is set to 1/3 of the thickness of the TFT substrate 100. In the TFT substrate 100 in this case, the point where the stress appears most is A 2 corresponding to the corner portion of the driver IC 40.

  FIG. 7C is a plan view of a terminal portion to which another example of this embodiment is applied. A difference from FIG. 7B is that the recess 60 is formed at a position overlapping the driver IC 40, that is, a position overlapping the region between the outermost bump 41 of the driver IC 40 and the end of the driver IC 40. It is. The dimensions and depth of the recess 60 are the same as in the case of FIG. In this case, the point where the stress is greatest in the TFT substrate 100 is A3, which is the intersection of the long sides of the recess 60 and the driver IC 40.

  FIG. 7D is a plan view of a terminal portion to which another example of this embodiment is applied. A difference from FIG. 7B is that a through hole 70 is formed at the position where the recess 60 was formed in FIG. 7B. The dimension of the through-hole 70 is the same as the recessed part 60 in FIG.7 (B). Further, in FIG. 7D, the point where the stress appears most on the TFT substrate 100 is A4 corresponding to the corner portion of the driver IC 40, and the position is the same as in FIG. 7B.

  FIG. 7E is a plan view of a terminal portion to which another example of this embodiment is applied. The difference from FIG. 7C is that a through hole 70 is formed at the position where the recess 60 was formed in FIG. 7C. The dimension of the through hole 70 is the same as that of the concave portion 60 in FIG. In this case, the point where the stress is greatest in the TFT substrate 100 is A4 which is the intersection of the long sides of the through hole 70 and the driver IC 40, and the position is the same as in the case of FIG.

  FIG. 8 is a table comparing the maximum stress values in FIGS. 7A to 7E. That is, FIG. 8 represents the shear stress in the XY plane direction in terms of MPa (megapascal) at A1 to A5, which is the point indicating the maximum stress in each of FIGS. 7 (A) to (E).

  In FIGS. 8B to 8E showing the present embodiment, the stress is smaller than that in the case where the present embodiment is not applied, and luminance unevenness and color unevenness in the display region due to the stress are reduced. It is possible to prevent the occurrence. For example, in FIG. 8C, the stress is reduced by 15% compared to FIG. 8A, and in FIG. 8E, the stress is reduced by 20% compared to FIG. 8A. Therefore, the curvature of the TFT substrate can be suppressed, and the influence on the assembly of the liquid crystal module can be reduced.

  FIG. 9 is a plan view showing another example of this embodiment. FIG. 9 shows an example in which the formation region of the recess 60 formed in the TFT substrate 100 is extended to the peripheral region 20 where the sealing material is formed. 9A shows a case where the concave portion 60 of the TFT substrate 100 is formed at a position overlapping the driver IC 40. FIG. 9B shows a case where the concave portion 60 of the TFT substrate 100 has a short side of the driver IC 40. It is a case where it is formed at a position. In FIG. 9, the end of the peripheral region 20 coincides with the end of the counter substrate 200, and the recess 60 is formed to overlap the peripheral region 20 by a width y from the end of the counter substrate 200.

  Since the recess 60 is formed extending to the peripheral region 20 side, that is, formed closer to the display region, the stress on the display region side can be further reduced. Therefore, the configuration of FIG. 9 has a great effect of reducing local luminance unevenness and color unevenness in the display area. In FIG. 9, the width of the recess 60 in the second direction Y can be extended to the end of the area where the sealing material is formed on the display area side.

  FIG. 10 is a cross-sectional view showing an example of the depth of the recess 60. In FIG. 10, a two-layer insulating film is formed on the TFT substrate 100. The first insulating film 110 and the second insulating film 120 may be inorganic insulating films or organic insulating films. The total thickness of the TFT substrate 100 and the insulating films 110 and 120 is t1, and the thickness of the TFT substrate 100 in the recess 60 is t2. In FIG. 10, t2 / t1 is desirably 0.9 or less, and more preferably 0.7 or less. Moreover, t2 is 1 μm or more when not penetrating.

  The TFT substrate 100 may be a glass substrate or may be formed of a resin such as polyimide. When the TFT substrate 100 is a glass substrate, it is about 0.15 mm, but when it is made of polyimide, it is about 10 μm to 20 μm. Since polyimide is mechanically strong, the required mechanical strength can be maintained even when t2 in FIG. 10 is about 1 μm.

  FIG. 11 is a diagram showing the relationship among the TFT substrate 100, the driver IC 40, and the ACF 50 in the present embodiment. FIG. 11A is a plan view showing a state where the recess 60 of the TFT substrate 100 overlaps the driver IC 40. In FIG. 11A, the amount d where the driver IC 40 and the recess 60 of the TFT substrate 100 do not overlap each other needs to be 3 μm or more.

  FIG. 11B is a cross-sectional view before thermocompression bonding. In FIG. 11B, the ACF 50 exists between the driver IC 40 and the TFT substrate 100. FIG. 11C shows a state where the driver IC 40 and the ACF 50 are heated and the ACF 50 is softened and flows into the recess 60 of the TFT substrate 100. As shown in FIG. 11C, even if the ACF 50 softens and flows, the ACF 50 can remain in the recess 60 of the TFT substrate 100, so that connection failure or the like due to the ACF 50 flowing and spreading can be prevented. I can do it.

  FIG. 12 is a diagram showing a relationship among the TFT substrate 100, the driver IC 40, and the ACF 50 in another example of this embodiment. FIG. 12A is a plan view showing a state in which the end of the recess 60 of the TFT substrate 100 and the end of the driver IC 40 are aligned. FIG. 12B is a cross-sectional view before thermocompression bonding. In FIG. 12B, the ACF 50 exists between the driver IC 40 and the TFT substrate 100. FIG. 12C shows a state in which the driver IC 40 and the ACF 50 are heated to soften the ACF 50 and flow into the recess 60 of the TFT substrate 100. As shown in FIG. 12C, even if the ACF 50 softens and flows, the ACF 50 can remain in the recess 60 of the TFT substrate 100, so that connection failure due to the ACF 50 can be prevented.

  In addition, when the concave portion 60 is formed on the glass substrate with a laser, a minute crack may occur in the concave portion 60. If there are minute cracks, the cracks may progress in this portion, and the TFT substrate may be broken. As shown in FIGS. 11 and 12, when the ACF 50 flows into the recess 60, the resin of the ACF 50 fills the microcracks existing in the recess 60, and the crack can be prevented from progressing.

  FIG. 13 is a plan view showing another example of the shape of the recess 60 in the present embodiment. In FIG. 13, the terminal part 30 in the TFT substrate 100 exists outside the peripheral region 20 where the sealing material is formed. The wiring 31 formed on the terminal portion 30 is connected to the bump 41 of the driver IC 40. In the example shown in FIG. 13, recesses 60 are formed on both sides of the wiring 31. Also in this case, the shear stress in the TFT substrate 100 can be reduced.

  FIG. 14 is a plan view showing still another example of the shape of the recess 60 in the present embodiment. In FIG. 14, the terminal part 30 in the TFT substrate 100 exists outside the peripheral part 20 where the sealing material is formed. The wiring 31 formed on the terminal portion 30 is connected to the bump 41 of the driver IC 40. In the example shown in FIG. 14, a recess 60 is formed extending between the rows of bumps 41 of the driver IC 40. Also in this case, the shear stress in the TFT substrate 100 can be reduced.

  FIG. 15 is a plan view showing still another example of the shape of the recess 60 in the present embodiment. In FIG. 15, the planar shape of the recess 60 formed in the TFT substrate 100 is a circle. The wiring 31 formed in the terminal portion 30 is the same as that shown in FIGS. 13 and 14 in that the wiring 31 is connected to the bump 41 of the driver IC 40. As shown in FIG. 15, the planar shape of the recess 60 formed in the TFT substrate 100 is not limited to a rectangle, and the object of the present invention can be achieved even with a curved shape such as a circle.

  FIG. 16 is a plan view of the display device 2 according to the second embodiment. FIG. 16 has substantially the same configuration as FIG. The difference from FIG. 1 is that the example shown in FIG. 16 is an organic EL display device. That is, pixels having an organic EL layer, a driving TFT, a selection TFT, and the like are formed in a matrix in the display region 10. In the peripheral region 20, a scanning line driving circuit and the like are formed.

  17 is a cross-sectional view taken along the line BB in FIG. In FIG. 17, in the display region 10 formed on the TFT substrate 100, a light emitting layer including an organic EL layer is formed, and a protective layer 220 made of SiN or SiO is formed covering the light emitting layer. A polarizing plate 230 is attached to cover the protective layer 220.

  In the organic EL display device, the TFT substrate 100 may be formed of a resin such as polyimide. Since the polyimide substrate is about 10 μm to 20 μm, the deformation of the TFT substrate 100 due to the thermocompression bonding of the driver IC 40 is large. As in the first embodiment, by forming the recess 60 or the through hole 70 in the vicinity of the short side of the driver IC 40, the stress caused by thermocompression bonding of the driver IC 40 to the TFT substrate 100 can be alleviated. Can be reduced. In particular, the effect is very large in an organic EL display device using a thin resin substrate. The position and shape of the recess, the position and shape of the through hole are the same as described in the first embodiment. In the liquid crystal display device, the TFT substrate 100 may be formed of a resin such as polyimide. In that case, the same effect can be obtained by using the same configuration as in the first and second embodiments.

  FIG. 18 is a plan view of the display device according to the third embodiment. 18 is different from FIGS. 1 and 16 in that the driver IC 40 is connected to the display device via the drive circuit board 80.

  The drive circuit board 80 is formed of a polyimide substrate having a thickness of about 30 μm. On the other hand, since the driver IC 40 is connected to the drive circuit board 80 by thermocompression bonding, the deformation of the drive circuit board 80 tends to be large. Therefore, similarly to the first and second embodiments, the recess 60 or the through hole 70 is formed in a portion corresponding to the end of the driver IC 40, so that stress due to thermocompression bonding can be reduced. The positions and shapes of the recesses or through holes 70 are the same as those described in the first embodiment.

  FIG. 19 is a plan view of the display device according to the fourth embodiment. In FIG. 19, a counter substrate is formed so as to cover the display region, and the TFT substrate and the counter substrate are bonded together by a sealing material 440 formed in the peripheral region 20. The driver IC 40 is mounted below the display panel, that is, below the TFT substrate 100. Further, the portion where the driver IC 40 is mounted overlaps with the sealing material 440 when viewed in plan.

  20 is a cross-sectional view taken along the line CC of FIG. In FIG. 20, a wiring 410 is formed on the TFT substrate 100, and an array layer 400 including TFTs and the like is formed thereon. On the array layer, a liquid crystal material is formed for a liquid crystal display device, and an organic EL layer is formed for an organic EL display device. The counter substrate 200 is bonded to the TFT substrate 100 with a sealing material 440.

  A through hole 430 is formed in the TFT substrate 100 at a position overlapping the region where the sealing material 440 is formed as viewed in a plan view. The driver IC 40 is connected to the TFT substrate 100 by the ACF 50 through the through hole 430. Also in this case, as in the first to third embodiments, in order to prevent the TFT substrate 100 from being deformed by stress when the driver IC 40 is thermocompression bonded, the TFT substrate 100 is provided at a position corresponding to the end portion of the driver IC 40. A recess 60 is formed in the substrate. Therefore, the same effects as those of the first to third embodiments can be obtained.

  In the example shown in FIG. 20, the case where the driver IC 40 is directly mounted on the lower side of the TFT substrate 100 is described. However, as shown in the third embodiment, the driver IC is connected via the drive circuit substrate 80. It can be applied even if it is done. In that case, the drive circuit board 80 has the same configuration as that of the third embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device, 2 ... Organic EL display device, 10 ... Display area | region, 20 ... Peripheral area | region, 30 ... Terminal part, 40 ... Driver IC, 41 ... Bump, 50 ... ACF, 60 ... Recessed part, 70 ... Through-hole, DESCRIPTION OF SYMBOLS 80 ... Drive circuit board | substrate, 100 ... TFT substrate, 110 ... 1st insulating film, 120 ... 2nd insulating film, 200 ... Opposite substrate, 220 ... Protective layer, 230 ... Polarizing plate, 400 ... Array layer, 410 ... Wiring, 430 ... through-hole, 440 ... seal material, 1000 ... crimping head, 1010 ... buffer sheet, 1100 ... backup stage, 1200 ... stand

Claims (17)

A display device having a first substrate on which a driver IC is mounted,
The driver IC is mounted on the first substrate through an anisotropic conductive film,
The display device, wherein the first substrate has a recess in the vicinity of the short side of the driver IC.   The display device according to claim 1, wherein the recess is formed to overlap the driver IC.   The display device according to claim 1, wherein a part of the recess is covered with a part of the anisotropic conductive film.   2. The display device according to claim 1, wherein the thickness of the first substrate in the recess is 1 μm or more and 90% or less of the thickness of the substrate in the portion where the recess is not formed.   2. The display device according to claim 1, wherein the thickness of the first substrate in the recess is 1 μm or more and 70% or less of the thickness of the substrate in a portion where the recess is not formed. A second substrate facing the first substrate;
The display device according to claim 1, wherein the first substrate and the second substrate are bonded by a sealing material.   The display device according to claim 6, wherein the concave portion formed in the first substrate overlaps with a part of the sealing material in a plan view.   The display device according to claim 1, wherein the recess is a through hole.   The display device according to claim 6, wherein the driver IC is mounted on a surface of the first substrate opposite to the second substrate.   The display device according to claim 6, wherein a liquid crystal layer is sandwiched between the first substrate and the second substrate.   The display device according to claim 6, wherein an organic EL layer is formed on the first substrate. A drive circuit board on which a driver IC for supplying a video signal to a display device is mounted,
The driver IC is mounted on the drive circuit board via an anisotropic conductive film,
The drive circuit board has a recess in the vicinity of the driver IC.   The drive circuit board according to claim 12, wherein the recess is formed to overlap the driver IC.   The drive circuit board according to claim 12, wherein a part of the recess is covered with a part of the anisotropic conductive film.   13. The drive circuit board according to claim 12, wherein the thickness of the drive circuit board in the recess is 1 μm or more and 90% or less of the thickness of the drive circuit board in a portion where the recess is not formed. .   13. The drive according to claim 12, wherein the thickness of the drive circuit board in the recess is 1 μm or more and 70% or less of the thickness of the drive circuit board in a portion where the recess is not formed. Circuit board.   The drive circuit board according to claim 12, wherein the recess is a through hole.

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