JP2007011030A - Display device and manufacturing method thereof - Google Patents

Abstract

An electrode portion 12 and electrode terminal pads 9 and 10 are reliably connected, and the connection resistance value is made uniform to improve the reliability of the display device.
A through hole 22 is formed in a second substrate 3 in a region facing the terminal region 7 of the first substrate 2, and at least a part of the circuit unit 12 is inserted into the through hole 22. In this state, the electrode portion 15 is connected to the electrode terminal pads 9 and 10 through the conductive particles of the anisotropic conductive resin 18.
[Selection] Figure 1

Description

  The present invention relates to a display device and a manufacturing method thereof.

  In general, it is well known that a driver which is a circuit unit for driving a liquid crystal display element or the like is mainly mounted on a glass substrate or the like (Chip On Glass: COG connection) (for example, Patent Document 1). reference).

  That is, a plurality of electrode terminal pads are formed on the glass substrate. On the other hand, a plurality of protruding bumps are formed as electrode portions in the liquid crystal driving driver. Then, the bumps of the driver are pressure-bonded to the electrode terminal pads of the glass substrate at a high temperature and a high pressure via an anisotropic conductive resin (ACF) in which conductive particles are dispersed in an insulating resin. Thereby, the bump of the driver is electrically connected to the electrode terminal pad of the glass substrate through the conductive particles in the anisotropic conductive resin.

  According to this COG connection, the cost of the liquid crystal display device can be reduced, the reliability can be improved, the thickness can be reduced, and the pitch between the electrode terminals can be reduced as compared with the conventional TCP (Tape Carrier Package) connection and solder connection. This is advantageous.

  In particular, in Patent Document 1, by providing a plurality of bumps for one electrode terminal pad, even if the height of the plurality of bumps is not uniform, the gap between the driver and the electrode terminal pad can be ensured. I try to make it conductive. However, since a large number of pads are required to achieve reliable conduction, the pad portion tends to have a complicated structure with high accuracy.

  It is also known to mount a flexible printed circuit (FPC) which is a circuit part on a glass substrate or the like (Film On Glass: FOG connection). The FOG connection is a connection method in which the electrode portion of the FPC is electrically connected to the electrode terminal pad of the glass substrate similarly to the COG connection, and has the same advantages as the COG connection.

  Next, a method for performing the COG connection or the FOG connection using an anisotropic conductive resin will be described with reference to FIG. 9 which is a cross-sectional view.

  First, the base material of the TFT substrate and the base material of the counter substrate are bonded together via a sealing material. As a result, a large panel having a certain gap between the substrate base materials is formed. In order to divide this large panel into an actual panel size, acute cracks are formed in a line shape on the TFT substrate base material and the counter substrate base material by a wheel. Thereafter, the cracks are extended by braking or aging, and the individual panels are separated.

  At this time, as shown in FIG. 9, in order to perform the COG connection or the FOG connection, it is necessary to divide the panel 100 into steps by shifting the dividing position of the TFT substrate 102 and the dividing position of the counter substrate 101 from each other. . Thus, the counter substrate 101 is cut out to be smaller than the TFT substrate 102 to expose the formation region (hereinafter referred to as a terminal region) 103 of the electrode terminal pad 107 in the TFT substrate 102.

  Next, a liquid crystal material is sealed in the cell gap between the TFT substrate 102 and the counter substrate 101, and polarizing plates (not shown) are attached to both outer surfaces of the panel 100. Note that the method of dividing the panel 100 and the steps of dividing, enclosing liquid crystal, and attaching a polarizing plate are not limited to the above order, and may be performed in different orders.

  Thereafter, the anisotropic conductive resin 104 is provided in the terminal region 103, and the alignment mark formed in the terminal region 103 and the alignment mark formed in the driver 105 are aligned. Subsequently, the driver 105 and the anisotropic conductive resin 104 are heated to a high temperature and a high pressure by a crimping tool, and the driver 105 is crimped to the electrode terminal pad 107 of the TFT substrate 102.

  As a result, the electrode terminal pad 107 of the TFT substrate 102 is electrically connected to the bump 106 of the driver 105 via conductive particles (not shown) that are deformed flat by pressure. Furthermore, the connection state between the electrode terminal pads 107 and the bumps 106 is maintained by the anisotropic conductive resin 104 heated to a high temperature and cured. Further, by filling the space between the bumps 106 with the anisotropic conductive resin 104, the reliability against corrosion and the reliability of the resistance value of the connection portion are improved.

  Also, the FPC 110 is FOG-connected to the terminal area 103 in the same manner as the driver 105. That is, the FPC 110 has the metal wiring 111 corresponding to the bumps, while the electrode terminal pad 112 is formed in the terminal region 103. The metal wiring 111 of the FPC 110 is brought into conduction with the electrode terminal pad 112 through conductive particles (not shown) of the anisotropic conductive resin 113 by being crimped.

Thus, the panel 100 on which the driver 105 and the FPC 110 are mounted is manufactured as a liquid crystal display device by being incorporated in a unit provided with a backlight or the like thereafter.
Japanese Patent Laid-Open No. 10-246894

  However, in the COG connection and the FOG connection, since the driver and the FPC are directly bonded to the glass substrate at a high temperature and a high pressure, residual stress is generated in each member due to a difference in temperature expansion coefficient. For this reason, there is a possibility that a positional deviation occurs between the bump and the electrode terminal pad after the crimping. Further, if the bumps and the electrode terminal pads have variations in dimensional accuracy, poor connection between the bumps and the electrode terminal pads is likely to occur even if the driver is slightly displaced.

  Furthermore, if the parallelism of the crimping tool varies, the flatness of the conductive particles tends to be uneven. As a result, in the mass-produced product, there is a problem that the connection resistance value in each bump becomes non-uniform and the display accuracy is lowered.

  The present invention has been made in view of such various points, and an object of the present invention is to reliably connect the electrode portion as the bump and the electrode terminal pad, and to uniformize the connection resistance value of the display device. It is to improve the reliability.

  In order to achieve the above object, in the present invention, the electrode portion of the circuit portion is connected to the electrode terminal pad of the first substrate in a state where at least a part of the circuit portion is fitted into the through hole of the second substrate. I did it.

  Specifically, a display device according to the present invention includes a first substrate having a terminal region in which a plurality of electrode terminal pads are formed, a second substrate disposed to face the first substrate, and the first substrate. And a display medium layer provided between the second substrates, a plurality of electrode parts connected to the electrode terminal pads, a circuit part for driving the display medium layer, and at least the electrode terminal pads A display device comprising an anisotropic conductive resin including conductive particles interposed between electrode portions of the circuit portion, wherein the second substrate faces a terminal region of the first substrate. A through hole is formed in the region, and the circuit part is inserted through the anisotropic conductive resin conductive particles in a state where at least a part of the circuit part is fitted into the through hole. Connected to the electrode terminal pad.

  It is preferable that the electrode portion is fitted in the through hole.

  The said through-hole may be provided for every said electrode part.

  The plurality of electrode portions may be collectively inserted into one through hole.

  The circuit part may be constituted by the electrode part and a chip part, and the chip part may be inserted into the through hole.

  The second substrate is constituted by a glass substrate, and the thickness of the glass substrate is preferably 10 μm or more and 80 μm or less.

  The second substrate may be made of a plastic substrate.

  The distance between the electrode part and the through hole is preferably larger than 2 μm and not larger than 20 μm.

-Action-
Next, the operation of the present invention will be described.

  A plurality of electrode terminal pads are formed in the terminal region of the first substrate. A through hole is formed in the second substrate in a region facing the terminal region of the first substrate. And the circuit part has the electrode part connected to the electrode terminal pad through the electroconductive particle of anisotropic conductive resin in the state in which the part was inserted by the through-hole. As a result, the signal of the circuit portion is transmitted from the electrode portion to the electrode terminal pad via the conductive particles, and the display medium layer is driven.

  Since the circuit portion is fitted into the through hole of the second substrate, it is supported by the inner wall surface of the through hole. Therefore, the position shift of the electrode part and electrode terminal pad accompanying the crimping | compression-bonding to the terminal area | region of a circuit part is suppressed. Therefore, even if there is variation in dimensional accuracy between the electrode part and the electrode terminal pad, it is possible to suppress poor connection between the electrode part and the electrode terminal pad. Furthermore, even if there is a variation in parallelism in the crimping tool for crimping the circuit part, the crimping force is supported by the second substrate in contact with the lower surface of the driver in addition to the electrode part, The variation in parallelism of the crimping tool is made uniform. Therefore, the flatness of the conductive particles sandwiched between the electrode part and the electrode terminal pad can be made uniform. As a result, the connection resistance between the electrode portion and the electrode terminal pad is made uniform, and the reliability of the display device is improved.

  When the electrode part is fitted into the through hole, the circuit part is supported by the through hole in the electrode part. In addition, when a through hole is provided for each electrode portion, each electrode portion is reliably supported by one through hole. On the other hand, when a plurality of electrode portions are collectively inserted into one through hole, each electrode portion is supported by the inner wall surface of the through hole as a whole, and therefore the circuit portion is supported by the through hole. Become. Further, when the chip portion is fitted into the through hole, the circuit portion is supported by the through hole in the chip portion.

  Further, when the thickness of the glass substrate constituting the second substrate is less than 10 μm, it is difficult to reliably support the circuit portion by the through hole. On the other hand, when the thickness of the glass substrate exceeds 80 μm, it takes a relatively long time to form the through hole, and thus does not follow the actual situation. Therefore, the thickness of the glass substrate is preferably 10 μm or more and 80 μm or less. Further, if the second substrate is made of a plastic substrate, the through hole can be easily formed.

  When the distance between the electrode portion and the through hole is 2 μm or less, mounting failure of the circuit portion is likely to occur in the manufacturing process. On the other hand, when the interval exceeds 20 μm, the positional deviation between the electrode portion and the electrode terminal pad becomes large, and connection failure is likely to occur. Accordingly, the distance between the electrode portion and the through hole is preferably larger than 2 μm and not larger than 20 μm.

  According to the present invention, the electrode portion and the electrode are connected by connecting the electrode portion of the circuit portion to the electrode terminal pad of the first substrate in a state where at least a part of the circuit portion is fitted in the through hole of the second substrate. The reliability of the display device can be improved by reliably connecting the terminal pads and making the connection resistance values uniform.

  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 embodiment.

Embodiment 1 of the Invention
1 to 4 show Embodiment 1 of the present invention. In this embodiment, the liquid crystal display device 1 whose display medium layer is the liquid crystal layer 4 will be described as an example of the display device.

  As shown in FIG. 1 which is an enlarged sectional view and FIG. 2 which is a plan view, the liquid crystal display device 1 includes a TFT substrate 2 which is a first substrate and a second substrate which is disposed so as to face the TFT substrate 2. And a liquid crystal layer 4 provided between the TFT substrate 2 and the counter substrate 3.

  The counter substrate 3 is formed with a common electrode, a color filter, etc. (not shown) on a glass substrate. The liquid crystal layer 4 is sealed with a seal member 5 as shown in FIG.

  The TFT substrate 2 is formed with a plurality of thin-film transistors (TFTs) as switching elements (not shown) on a glass substrate. Further, as shown in FIG. 2, the TFT substrate 2 has a display region 6 that contributes to display and a terminal region 7 that does not contribute to display. The display region 6 is provided with a plurality of pixels (not shown) arranged in a matrix, and the TFT is arranged for each pixel.

  Circuit portions 12 and 13 for driving the liquid crystal layer 4 by controlling the TFTs are mounted on the terminal region 7. For example, the circuit unit 12 is a driver 12 such as an IC, and the circuit unit 13 is an FPC (flexible printed circuit) 13. The FPC 13 is disposed on the end side of the TFT substrate 2, while the driver 12 is disposed on the display area 6 side of the FPC 13. The FPC 13 supplies a control signal to the driver 12.

  As shown in FIG. 1, the FPC 13 has a plurality of metal wirings 14 that are electrode portions. Each metal wiring 14 is provided in a line in the width direction of the FPC 13 (that is, the direction perpendicular to the paper surface in FIG. 1 and the left-right direction in FIG. 2). On the other hand, the driver 12 includes, for example, a rectangular parallelepiped chip portion 16 and a plurality of bumps 15 which are electrode portions provided on the back surface of the chip portion 16. Each bump 15 is provided in two rows in the length direction of the chip portion 16 (that is, the direction perpendicular to the paper surface in FIG. 1 and the left-right direction in FIG. 2). The bumps 15 are configured by input-side bumps 15a arranged in a row on the FPC 13 side and output-side bumps 15b arranged in a row on the display area 6 side.

  A plurality of electrode terminal pads 8 to 10 are formed in the terminal region 7. Each electrode terminal pad 8 is arranged corresponding to each metal wiring 14 of the FPC 13. Each electrode terminal pad 9 is provided corresponding to each input-side bump 15 a of the driver 12. Each electrode terminal pad 10 is arranged corresponding to each output-side bump 15 b of the driver 12.

  By the way, although not shown, a source wiring and a gate wiring are connected to each of the TFTs, and ends of the source wiring and the gate wiring are drawn out to the terminal region 7 by a lead wiring (not shown). . Each electrode terminal pad 10 is formed at the end of each lead-out wiring. Each electrode terminal pad 9 is connected to each electrode terminal pad 8.

  The driver 12 is COG-connected to the TFT substrate 2. As shown in an enlarged view in FIG. 4, each bump 15 of the driver 12 is connected to the electrode terminal pads 9 and 10 via an anisotropic conductive resin 18 including conductive particles 17. That is, the input side bump 15 a is connected to the electrode terminal pad 9 via the conductive particles 17, while the output side bump 15 b is connected to the electrode terminal pad 10 via the conductive particles 17.

  The anisotropic conductive resin 18 only needs to be interposed at least between the electrode terminal pads 9 and 10 and the bumps 15 of the driver 12, but is provided so as to cover the electrode terminal pads 9 and 10 and the bumps 15. Is preferred. As a result, the electrode terminal pads 9 and 10 and the bumps 15 can be protected by the insulating resin portion of the anisotropic conductive resin 18.

  On the other hand, the FPC 13 is FOG-connected to the TFT substrate 2. Similar to the bumps 15 of the driver 12, the metal wiring 14 of the FPC 13 is connected to the electrode terminal pad 8 through an anisotropic conductive resin 19 containing conductive particles. In this way, the control signal output from the FPC 13 is supplied to the driver 12 through the metal wiring 14, the electrode terminal pads 8, 9 and the input side bump 15a. Thereafter, the drive signal output from the driver 12 is supplied to the TFT via the output-side bump 15b, the electrode terminal pad 10, the lead wiring, and the like. As a result, each TFT is controlled, and the liquid crystal layer 4 is driven for each pixel, so that a desired display is performed.

  In the present embodiment, the counter substrate 3 is formed in the same rectangular shape as the TFT substrate 2, and the terminal region 7 of the TFT substrate 2 overlaps a part of the counter substrate 3. As shown in FIG. 3, which is a plan view, the counter substrate 3 is formed with a plurality of through holes 21 and 22 in a region facing the terminal region 7 of the TFT substrate 2. Each through hole 21 is formed corresponding to each metal wiring 14 of the FPC 13. On the other hand, each through hole 22 is formed corresponding to each bump 15 of the driver 12.

  As shown in FIG. 4, the driver 12 has the electrode terminal pad 9 with the bump 15 interposed through the conductive particles 17 of the anisotropic conductive resin 18 in a state where each bump 15 is inserted into the through hole 22. , 10. Further, in the FPC 13, the metal wiring 14 is connected to the electrode terminal pad 8 through the conductive particles of the anisotropic conductive resin 19 in a state where the respective metal wirings 14 are respectively inserted into the through holes 21. At this time, the back surface of the chip portion 16 of the driver 12 and the bottom surface of the FPC 13 are in contact with and supported by the surface of the counter substrate 3.

  The through hole 21 is formed slightly larger than the outer shape of the metal wiring 14, and the through hole 22 is formed slightly larger than the outer shape of the bump 15. The distance between the bump 15 or the metal wiring 14 and the through holes 21 and 22 is greater than 2 μm and less than or equal to 20 μm.

  When the distance between the bump 15 or the metal wiring 14 and the through holes 21 and 22 is 2 μm or less, mounting failure of the driver 12 or the FPC 13 is likely to occur in the manufacturing process. On the other hand, when the interval exceeds 20 μm, the positional deviation between the bump 15 or the metal wiring 14 and the electrode terminal pads 8 to 10 becomes large, and connection failure is likely to occur. Therefore, the distance between the bump 15 or the metal wiring 14 and the through holes 21 and 22 is preferably larger than 2 μm and not larger than 20 μm.

  Moreover, the thickness of the glass substrate which comprises the counter substrate 3 is 10 micrometers or more and 80 micrometers or less. When the thickness of the glass substrate is less than 10 μm, it becomes difficult to reliably support the driver 12 or the FPC 13 by the through holes 21 and 22. On the other hand, if the thickness of the glass substrate exceeds 80 μm, it takes a relatively long time to form the through-holes 21 and 22, so that the actual situation is not met. Therefore, the thickness of the glass substrate constituting the counter substrate 3 is preferably 10 μm or more and 80 μm or less.

-Effect of Embodiment 1-
The driver 12 can be supported by the inner wall surface of the through hole 22 because the bump 15 is inserted into the through hole 22 of the counter substrate 3. In addition, the FPC 13 can be supported by the inner wall surface of the through hole 21 because the metal wiring 14 is inserted into the through hole 21. Therefore, since the movement of the driver 12 and the FPC 13 in the direction parallel to the counter substrate 3 can be restricted at the time of crimping to the terminal region 7, the positional deviation between the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10 is suppressed. Can do.

  In addition, if the bump 15, the metal wiring 14, and the electrode terminal pads 8 to 10 have variations in dimensional accuracy, a connection failure is likely to occur due to a slight misalignment. However, according to the present embodiment, the through holes 21 and 22 are provided. Therefore, the displacement of the bumps 15 and the metal wiring 14 and the electrode terminal pads 8 to 10 can be suppressed, so that the connection failure between the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10 can be suitably reduced.

  Furthermore, even if there is a variation in parallelism on the crimping surface of the crimping tool for crimping the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10, the crimping force is applied to the lower surface of the driver 16 in addition to the bump 15. Since it is supported by the counter substrate 3 that is in contact with the substrate, variation in parallelism of the crimping tool can be made uniform. Therefore, the flatness of the conductive particles sandwiched between the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10 can be made uniform. As a result, the connection resistance between the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10 can be made uniform, and the reliability of the display device can be improved.

  Further, since the mounting area of the driver 12 is covered with glass having excellent hygroscopicity (moisture permeability) and thermal expansibility, permeation of surrounding moisture, contaminants, heat and the like can be suppressed. As a result, it is possible to improve the reliability of the connection resistance value against high temperature and high humidity and thermal shock, and the stability of the display state in a high temperature and high humidity environment.

  Furthermore, since the dividing lines overlap in the pair of substrates 2 and 3 to be divided, the extension direction of the cracks can be stabilized. That is, it is possible to reduce the division failure.

  Furthermore, since the through holes 21 and 22 are provided for each bump 15 and each metal wiring 14, each bump 15 and each metal wiring 14 can be reliably supported by one through hole 21 and 22, respectively.

  In addition, since the thickness of the glass substrate of the counter substrate 3 is 10 μm or more and 80 μm or less, the through holes 21 and 22 are formed in a relatively short time while the driver 12 and the FPC 13 are reliably supported by the through holes 21 and 22. can do.

  Further, since the distance between the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10 is set to 2 μm or more and 20 μm or less, mounting failure of the driver 12 and the FPC 13 in the manufacturing process hardly occurs, and the bump 15 and the metal wiring 14 The positional deviation from the electrode terminal pads 8 to 10 can be reduced.

  In addition, since the back surface of the chip portion 16 of the driver 12 and the back surface of the FPC 13 are brought into contact with the surface of the glass substrate in the counter substrate 3, the pressure at the time of crimping is applied not only to the end surface of the bump 15 but also to the surface of the glass substrate. And the flatness of the conductive particles can be made more uniform.

<< Embodiment 2 of the Invention >>
FIG. 5 shows Embodiment 2 of the present invention. In the following embodiments, the same parts as those in FIGS. 1 to 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the first embodiment, the through hole 22 is provided for each bump 15 of the driver 12 and the through hole 21 is provided for each metal wiring 14 of the FPC 13, whereas in the present embodiment, the plurality of bumps 15 are provided. One through-holes 21 and 22 are provided for the entire metal wiring 14 or the entire metal wiring 14.

  That is, one through hole 22 is formed for each driver 12. As shown in FIG. 5, which is an enlarged cross-sectional view, the entirety of the plurality of bumps 15 of the driver 12 is inserted into one through hole 22. Similarly, with respect to the through hole 21, the entirety of the plurality of metal wires 14 of the FPC 13 is inserted into the single through hole 21. A slight gap is provided between the bump 15 and the metal wiring 14 and the through holes 21 and 22.

  Even in this case, since the driver 12 and the FPC 13 can support the side surfaces of the bump 15 and the metal wiring 14 by the inner wall surfaces of the through holes 21 and 22, the positions of the bump 15 and the metal wiring 14 and the electrode terminal pads 8 to 10. Deviation can be suppressed. Furthermore, since the number of through holes 21 and 22 is significantly reduced, the through holes 21 and 22 can be formed by a simple method.

<< Embodiment 3 of the Invention >>
FIG. 6 shows Embodiment 3 of the present invention. In the second embodiment, the bump 15 portion of the driver 12 is supported by the through hole 22. In the present embodiment, the chip portion 16 of the driver 12 is supported by the through hole 22.

  One through hole 22 is formed for each driver 12. As shown in FIG. 6, which is an enlarged cross-sectional view, a part of the tip portion 16 of the driver 12 protrudes from the glass substrate in a state of being inserted into the through hole 22. That is, the lower side surface of the tip portion 16 is supported by the inner wall surface of the through hole 22. A slight gap is provided between the tip portion 16 and the through hole 22.

  Even in this case, since the driver 12 can support the side surface of the chip portion 16 by the inner wall surface of the through-hole 22, the positional deviation between the bump 15 and the electrode terminal pads 9 and 10 can be suppressed. Further, similarly to the second embodiment, the through hole 22 can be formed by a simple method.

<< Embodiment 4 of the Invention >>
FIG. 7 shows Embodiment 4 of the present invention. Although the driver 12 of the first embodiment has the bump 15 as the electrode portion, the driver 12 of the present embodiment has the through electrode 25 as the electrode portion. On the other hand, the FPC 13 of the first embodiment has the metal wiring 14 as the electrode portion, but the FPC 13 of the present embodiment has the through electrode 24 as the electrode portion.

  The through-electrodes 24 and 25 are formed in a needle shape with a narrow end on the side connected to the electrode terminal pads 8 to 10.

  The FPC 13 is connected to the electrode terminal pad 8 in a state where the through electrode 24 is inserted into the through hole 21, and is fixed by a general-purpose adhesive. Similarly, the driver 12 is connected to the electrode terminal pads 9 and 10 in a state where the through electrode 25 is inserted into the through hole 22 and is fixed by a general-purpose adhesive.

  According to the present embodiment, as in the first embodiment, in addition to being able to suppress the positional deviation between the through electrodes 24 and 25 and the electrode terminal pads 8 to 10, the electrode portion is configured by the through electrodes 24 and 25. Even if an anisotropic conductive resin is not used, it is possible to reliably establish conduction between the through electrodes 24 and 25 and the electrode terminal pads 8 to 10. That is, since the through hole 22 is provided, the electrode portion can be constituted by the through electrodes 24 and 25 in addition to the bump 15.

<< Embodiment 5 of the Invention >>
FIG. 8 shows Embodiment 5 of the present invention. In the first embodiment, the counter substrate 3 is made of a glass substrate, but in the present embodiment, the counter substrate 3 is made of a plastic substrate. Thus, since the counter substrate 3 can be formed thin, the liquid crystal display device can be thinned as a whole. Furthermore, for example, when the through holes 21 and 22 are formed by a laser beam, the through holes 21 and 22 can be easily formed because the processing can be performed in a shorter time than a glass substrate.

<< Other Embodiments >>
The present invention is not limited to the liquid crystal display device described above, and can be similarly applied to other display devices such as an organic EL display device in which the display medium layer is an organic EL layer.

(Example)
Next, examples in which the present invention is specifically implemented will be described.

  The width of the bump 15 in the driver 12 is set to 30 μm, and the time required for forming the through hole 22 by changing the material of the counter substrate 3, the thickness of the counter substrate 3, and the width of the through hole 22, the bump 15 and the electrode terminal pad 9, 10 maximum displacement, right and left pressure difference in bump 15, reliability (stability of connection resistance against high temperature and high humidity and thermal shock, and stability of display state in high temperature and high humidity environment), and division Each of the defects was measured (Examples 1 to 6, Comparative Example 2). Further, a conventional configuration in which the driver 12 is not supported by the through hole 22 was also measured (Comparative Example 1). The results are shown in Table 1.

  In Comparative Example 1, the material of the counter substrate 3 was glass, and the thickness of the counter substrate 3 was 500 μm. At that time, the maximum positional deviation amount was relatively large at 10 μm. With respect to the left-right pressure difference, the crushing amount of the conductive particles 17 on the left and right sides of the bump 15 was different at a predetermined ratio. Moreover, the reliability was low. There were very many breakage defects of 1000 ppm. This is because, in order to expose the terminal region 7, the liquid crystal display panel needs to be divided into steps, and in this case, the extension direction of a crack provided in advance in the glass substrate becomes unstable.

  In Example 1, the material of the counter substrate 3 was glass, the thickness of the counter substrate 3 was 500 μm, and the width of the through hole 22 was 36 μm. At this time, the formation of the through-hole 22 took a relatively long time of 300 minutes, but the maximum positional deviation amount could be reduced to 3 μm. This is because the misalignment during crimping can be controlled by a slight gap between the bump 15 and the through hole 22 (that is, a slight gap between the outer wall surface of the bump 15 and the inner wall surface of the through hole 22). It is thought that.

  Here, in Example 1, a total gap of 6 μm (36-30) is provided on both the left and right sides of the bump 15. If the displacement of the bump 15 is zero, a gap of 3 μm is provided on both the left and right sides of the bump 15. Therefore, the positional deviation amount of the bump 15 (the deviation amount of the central position of the bump 15) is 3 μm at the maximum.

  As for the left-right pressure difference, substantially no difference was observed between the left and right sides of the bump 15. This is considered to be because the bump 15 supported all the pressure at the time of pressure bonding in Comparative Example 1, whereas in Example 1, the pressure was dispersed not only by the bump 15 but also by the glass surface around the through hole 22. It is done.

  As for reliability, there was little increase in resistance value, and no defective display was observed. This is because the mounting region of the driver 12 is covered with glass having excellent hygroscopicity (moisture permeability) and thermal expansibility, so that permeation of surrounding moisture, contaminants, heat, and the like is suppressed, and resistance to these is suppressed. This is thought to be due to the improvement.

  In Example 2, the thickness of the glass substrate was changed to 150 μm with respect to Example 1. In Example 3, the thickness of the glass substrate was changed to 80 μm compared to Example 1. Furthermore, in Example 4, the thickness of the glass substrate was changed to 40 μm with respect to Example 1.

  At this time, in Examples 2 to 4, as in Example 1, the maximum positional deviation amount could be reduced to 3 μm, and the left-right pressure difference and reliability could be improved. Furthermore, the penetration time of Example 2 was reduced to 100 minutes, the penetration time of Example 3 was further reduced to 10 minutes, and the penetration time of Example 4 was significantly reduced to 2 minutes. This is presumably because a large energy loss occurs when a glass substrate having a thickness of more than 80 μm is melted with laser light.

  In addition, it was found that the rate of occurrence of poor separation was 5 ppm, which can be greatly improved as compared with 1000 ppm of the comparative example. This is considered to be because the extending direction of the cracks can be stabilized because the dividing lines overlap in the pair of substrates 2 and 3 to be divided.

  In Examples 2-4, it turned out that a parting defect can also be reduced significantly compared with the comparative example 1. FIG. In addition, it is considered that the reason for the slight increase in the separation failure compared to Example 1 is that the rigidity of the glass substrate is reduced because the thickness of the glass substrate is reduced, and it is easily affected by the variation in pressure applied during the separation. .

  In Example 5, the width of the through hole 22 was changed from 36 μm to 50 μm with respect to Example 4. The through hole 22 could be formed in a relatively short time of 4 minutes. Although the maximum positional deviation amount was 7 μm, which was smaller than 10 μm of Comparative Example 1, it was larger than 3 μm of Examples 1 to 4 described above.

  Moreover, although it was confirmed that the reliability can be improved as compared with Comparative Example 1, it was found that the reliability is slightly lower than those of Examples 1 to 4. This is considered to be because by increasing the width of the through hole 22 with respect to the width of the bump 15, the proportion of the glass around the bump 15 is reduced and the proportion of the resin is increased.

  In Example 6, the material of the counter substrate 3 was changed to plastic (epoxy resin) as compared to Example 4. Similar to Example 4, the thickness of the substrate was 40 μm, and the width of the through hole 22 was 36 μm with respect to the width of the bump 15 of 30 μm.

  It has been found that the formation of the through-hole 22 takes 1 minute and can be formed in a very short time. This is presumably because the plastic substrate is more easily melted than the glass substrate when the through-hole 22 is formed by the laser beam.

  Although it was confirmed that the reliability could be improved as compared with Comparative Example 1, it was found that the reliability was slightly lowered as compared with Example 4 in which the substrate was glass. This is considered to be because the plastic substrate itself tolerates ambient moisture, contaminants and heat to some extent.

  Moreover, about the division | segmentation defect, the board | substrate excavation method by the dicing method was applied instead of the wheel cutter system applied in each said Examples 1-5. Due to this, no occurrence of poor separation was observed.

  In this example, the epoxy resin was applied to the plastic substrate. However, it has been confirmed that the same effect can be obtained by using a resin such as PES, acrylic resin, and polycarbonate resin. Moreover, although the constant heat system was applied to the crimping | compression-bonding of the driver 12 in each said Example, it has confirmed that the same effect is acquired even if it applies a pulse heat system to others.

  In Comparative Example 2, the width of the through hole 22 was changed from 36 μm to 32 μm with respect to Example 4. In this case, when the mounting process was performed after alignment for alignment, it was confirmed at a rate of several percent that the bumps 15 climbed onto the glass substrate without being inserted into the through holes 22. This is considered to be because the width of the through hole 22 with respect to the width of the bump 15 is too small, and the margin for the alignment accuracy of the apparatus is reduced.

  As described above, the present invention is useful for a display device and a method for manufacturing the same, and in particular, the electrode portion and the electrode terminal pad are reliably connected, and the connection resistance value is made uniform to improve the reliability of the display device. It is suitable for improving.

1 is an enlarged cross-sectional view illustrating a liquid crystal display device according to Embodiment 1. FIG. It is a top view which shows the external appearance of a liquid crystal display device. It is a top view which expands and shows a terminal area | region. It is an expanded sectional view which shows the driver inserted by the through-hole. FIG. 6 is an enlarged cross-sectional view showing a driver fitted into a through hole in Embodiment 2. FIG. 10 is an enlarged cross-sectional view showing a driver fitted into a through hole in Embodiment 3. It is sectional drawing which expands and shows the liquid crystal display device of Embodiment 4. FIG. 9 is an enlarged cross-sectional view illustrating a liquid crystal display device according to a fifth embodiment. It is sectional drawing which expands and shows the conventional liquid crystal display device.

Explanation of symbols

1 Liquid crystal display device (display device)
2 TFT substrate (first substrate)
3 Counter substrate (second substrate)
4 Liquid crystal layer (display medium layer)
7 Terminal area, frame area 8-10 Electrode terminal pad 12 Driver (circuit part)
13 FPC (circuit part)
14 Metal wiring (electrode part)
15 Bump (electrode part)
16 Chip part 17 Conductive particle 18 Anisotropic conductive resin 19 Anisotropic conductive resin 21, 22 Through hole

Claims (8)

A first substrate having a terminal region in which a plurality of electrode terminal pads are formed;
A second substrate disposed opposite the first substrate;
A display medium layer provided between the first substrate and the second substrate;
A plurality of electrode portions connected to the electrode terminal pads, and a circuit portion for driving the display medium layer;
A display device comprising at least the electrode terminal pad and the electrode portion of the circuit portion, and an anisotropic conductive resin containing conductive particles,
In the second substrate, a through hole is formed in a region facing the terminal region of the first substrate,
In the circuit part, the electrode part is connected to the electrode terminal pad via conductive particles of the anisotropic conductive resin in a state where at least a part of the circuit part is fitted in the through hole. A display device. In claim 1,
The display device, wherein the electrode portion is inserted into the through hole. In claim 2,
The display device, wherein the through hole is provided for each of the electrode portions. In claim 2,
The display device, wherein the plurality of electrode portions are collectively inserted into one through hole. In claim 1,
The circuit part is constituted by the electrode part and a chip part,
The display device, wherein the chip portion is inserted into the through hole. In claim 2,
The second substrate is composed of a glass substrate,
The thickness of the said glass substrate is 10 micrometers or more and 80 micrometers or less, The display apparatus characterized by the above-mentioned. In claim 1,
The display device, wherein the second substrate is formed of a plastic substrate. In claim 2,
A display device, wherein a distance between the electrode portion and the through hole is larger than 2 μm and not larger than 20 μm.

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