JP2013235127A - Electro-optic device, method for manufacturing electro-optic device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electro-optic device and a method for manufacturing an electro-optic device capable of improving display qualities, and an electronic apparatus.SOLUTION: The electro-optic device includes, on a first substrate 10a: a connection pad 61 to be electrically connected to an FPC terminal 66 via an anisotropic conductive adhesive film 65; and a plurality of plugs 64 disposed below the connection pad 61 and in contact with the connection pad 61. The plurality of plugs 64 is formed like grooves, in which the width between adjoining plugs 64 of the plurality of plugs 64 is smaller than a diameter of metal particles included in the anisotropic conductive adhesive film 65.

Description

  The present invention relates to an electro-optical device, a method for manufacturing the electro-optical device, and an electronic apparatus.

  As the electro-optical device, for example, an active drive type liquid crystal device including a transistor for each pixel as an element for controlling switching of a pixel electrode is known. Liquid crystal devices are used in, for example, direct view displays and light valves.

  The external connection terminal portion for connecting to the outside in the liquid crystal device includes, for example, a connection pad provided in the same layer as the reflective pixel electrode as described in Patent Document 1, and an ACF (differential electrode) having metal particles. Isotropic contact adhesive film) and an external connection terminal, and these are electrically connected.

JP 2000-187238 A

  However, due to the thickness of the connection pad and the pixel electrode, a step is generated on the surface of the film laminated on the upper layer, and the contrast may be lowered. Therefore, if the film thickness of the connection pad is reduced together with the pixel electrode, the connection pad may be crushed and damaged (destructed) by the metal particles when the external connection terminal is crimped and connected to the connection pad. There is a problem that the connection reliability between the external connection terminal and the connection pad is lowered.

  An aspect of the present invention has been made to solve at least a part of the above problems, and can be realized as the following forms or application examples.

  Application Example 1 An electro-optical device according to this application example includes a substrate, a connection pad for electrical connection with the first electrode via an anisotropic conductive adhesive film, the connection pad, and the substrate. A plurality of plugs disposed in contact with the connection pads, the plurality of plugs being provided in a groove shape in plan view, and between adjacent plugs of the plurality of plugs The width of is equal to or smaller than the diameter of the metal particles contained in the anisotropic conductive adhesive film.

  According to this application example, since the plug is provided between the connection pad and the substrate so as to contact the connection pad, the first electrode and the connection pad are pressure-bonded and connected via the anisotropic conductive adhesive film. Thus, when electrically connected, it is possible to receive stress at both the connection pad and the plug. Further, the metal particles can be received by a plurality of plugs having a groove width equal to or smaller than the diameter of the metal particles contained in the anisotropic conductive adhesive film. Therefore, even if the connection pad is destroyed, the plug disposed under the connection pad and the first electrode can be reliably electrically connected.

  Application Example 2 In the electro-optical device according to the application example, the substrate, the plurality of reflective pixel electrodes provided on one surface side of the substrate corresponding to the plurality of pixels, and the plurality of reflective pixel electrodes. A connection pad provided in the same layer, a wiring layer provided between the connection pad and the substrate, and a plurality of plugs connecting the wiring layer and the connection pad. The plurality of plugs are formed in a groove shape along one side of the connection pad.

  According to this application example, since the plurality of plugs connected to the connection pad and formed in a groove shape along one side of the connection pad are provided, for example, through the anisotropic conductive adhesive film When one electrode and the connection pad are connected by crimping and electrically connected, it is possible to receive stress by both the connection pad and the plug. Moreover, the metal particles contained in the anisotropic conductive adhesive film can be received by a plurality of plugs provided in a groove shape. Therefore, even if the connection pad is destroyed, the plug disposed under the connection pad and the first electrode can be reliably electrically connected.

  Application Example 3 In the electro-optical device according to the application example described above, it is preferable that the plug has a region that is not arranged in a region that overlaps with the connection pad for supplying a constant potential.

  According to this application example, there is a region in which the plug is not arranged in the region overlapping the connection pad for supplying a constant potential in a planar manner. Short circuit (migration) that occurs can be suppressed. For example, the plug is not disposed below the connection pad disposed on both sides of the connection pad to which the power supply voltage is applied. Therefore, electrical reliability can be improved.

  Application Example 4 A method of manufacturing an electro-optical device according to this application example is a plug formation in which a groove-like plug having a gap equal to or smaller than the diameter of metal particles included in an anisotropic conductive adhesive film is formed on a substrate. A connection pad forming step for forming a connection pad for electrical connection with the first electrode through the anisotropic conductive adhesive film so as to contact the plug on the upper layer of the plug; and A crimping step of crimping the first electrode and the connection pad through an anisotropic conductive adhesive film to electrically connect the first electrode and the connection pad; To do.

  According to this application example, since the connection pad is formed on the plug formed, when the first electrode and the connection pad are pressure-bonded and electrically connected via the anisotropic conductive adhesive film, The stress can be received by both the connection pad and the plug. Further, the metal particles can be received by a plurality of plugs having a groove width equal to or smaller than the diameter of the metal particles contained in the anisotropic conductive adhesive film. Therefore, even if the connection pad is destroyed, the plug disposed under the connection pad and the first electrode can be reliably electrically connected.

  Application Example 5 In the method of manufacturing an electro-optical device according to the application example described above, a pixel electrode is connected to the substrate through a contact hole, and the plug formation step includes the plug at the same time as the contact hole. It is preferable to form.

  According to this application example, since the plug is formed at the same time as the contact hole, it is not necessary to add a new manufacturing process, and the cost can be suppressed. Further, if the plug has the same width as the contact hole, it can be formed at the same etching rate at the same time.

  Application Example 6 An electronic apparatus according to this application example includes the electro-optical device described above.

  According to this application example, since the electro-optical device described above is provided, an electrically stable electronic apparatus can be provided.

FIG. 2 is a schematic plan view illustrating a configuration of a liquid crystal device. FIG. 2 is a schematic cross-sectional view taken along line H-H ′ of the liquid crystal device illustrated in FIG. 1. FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device. FIG. 3 is a schematic cross-sectional view illustrating a structure of a liquid crystal device. It is a schematic diagram which shows the structure around the terminal for external connection, (a) is a schematic top view, (b) is a schematic cross section along an A-A 'line. 5 is a flowchart showing a method for manufacturing a liquid crystal device in the order of steps. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing a part of the liquid crystal device. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing a part of the liquid crystal device. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing a part of the liquid crystal device. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing a part of the liquid crystal device. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing a part of the liquid crystal device. Schematic which shows the structure of the projection type display apparatus as an electronic device provided with the liquid crystal device. The schematic plan view which shows arrangement | positioning of the plug of a modification.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. Note that the drawings to be used are appropriately enlarged or reduced so that the part to be described can be recognized.

  In the following embodiments, for example, when “on the substrate” is described, the substrate is disposed so as to be in contact with the substrate, or is disposed on the substrate via another component, or the substrate. It is assumed that a part is arranged so as to be in contact with each other and a part is arranged via another component.

  In the present embodiment, an active matrix liquid crystal device including a thin film transistor (TFT) as a pixel switching element will be described as an example of an electro-optical device. This liquid crystal device can be suitably used, for example, as a light modulation element (liquid crystal light valve) of a projection display device (liquid crystal projector).

<Liquid crystal device as electro-optical device>
First, the liquid crystal device of this embodiment will be described with reference to FIGS. FIG. 1 is a schematic plan view showing the configuration of the liquid crystal device. 2 is a schematic cross-sectional view taken along the line HH ′ of the liquid crystal device shown in FIG. FIG. 3 is an equivalent circuit diagram showing an electrical configuration of the liquid crystal device.

  As shown in FIGS. 1 and 2, the liquid crystal device 100 according to the present embodiment includes an element substrate 10 and a counter substrate 20 that are disposed to face each other, and a liquid crystal layer 15 that is sandwiched between the pair of substrates. As the first base material 10a as a substrate constituting the element substrate 10 and the second base material 20a constituting the counter substrate 20, for example, a transparent substrate such as a glass substrate or a quartz substrate is used. In the case of the reflective liquid crystal device 100 as in the present embodiment, the first substrate 10a may be a silicon substrate.

  The element substrate 10 is larger than the counter substrate 20, and both the substrates are bonded via a sealing material 14 disposed along the outer periphery of the counter substrate 20. Liquid crystal layer 15 is configured by sealing liquid crystal having positive or negative dielectric anisotropy in the gap. For the sealing material 14, for example, an adhesive such as a thermosetting or ultraviolet curable epoxy resin is employed. Spacers (not shown) are mixed in the sealing material 14 to keep the distance between the pair of substrates constant.

  A pixel region E in which a plurality of pixels P are arranged is provided inside the sealing material 14. The pixel region E may include dummy pixels arranged so as to surround the plurality of pixels P in addition to the plurality of pixels P contributing to display.

  A data line driving circuit 22 is provided between the sealing material 14 along one side of the element substrate 10 and the one side. In addition, an inspection circuit 25 is provided between the sealing material 14 and the pixel region E along the other one side facing the one side. Further, a scanning line driving circuit 24 is provided between the sealing material 14 and the pixel region E along the other two sides orthogonal to the one side and facing each other. A plurality of wirings 29 connecting the two scanning line driving circuits 24 are provided between the sealing material 14 and the inspection circuit 25 along the other one side facing the one side.

  Inside the sealing material 14 arranged in a frame shape on the counter substrate 20 side, a light shielding portion 18 (parting portion) is also provided in the same frame shape. The light shielding portion 18 is made of, for example, a light shielding metal or metal oxide, and the inside of the light shielding portion 18 is a pixel region E having a plurality of pixels P.

  Wirings connected to the data line driving circuit 22 and the scanning line driving circuit 24 are connected to a plurality of external connection terminals 61 (connection pads) arranged along the one side. Hereinafter, the direction along the one side will be referred to as the X direction, and the direction along the other two sides orthogonal to the one side and facing each other will be described as the Y direction. The arrangement of the inspection circuit 25 is not limited to this, and the inspection circuit 25 may be provided between the sealing material 14 along the data line driving circuit 22 and the pixel region E.

  As shown in FIG. 2, on the surface of the first base material 10a on the liquid crystal layer 15 side, a light-reflective pixel electrode 27 provided for each pixel P and a thin film transistor (TFT) as a switching element are provided. Hereinafter, this will be referred to as “TFT 30”), signal wirings, and a first alignment film 28 covering them.

  The pixel electrode 27 can be formed using a light reflective compound such as aluminum (Al), silver (Ag), or an alloy or oxide of these metals. In addition, a light shielding structure is employed that prevents light from entering the semiconductor layer in the TFT 30 to make the switching operation unstable. As described above, the element substrate 10 includes at least the pixel electrode 27, the TFT 30, the signal wiring, and the first alignment film 28.

  On the surface of the counter substrate 20 on the liquid crystal layer 15 side, the light shielding portion 18, the planarizing layer 33 formed so as to cover the light shielding portion 18, and the common electrode 31 provided so as to cover the planarizing layer 33 are shared. A second alignment film 32 covering the electrode 31 is provided.

  As shown in FIG. 1, the light shielding unit 18 surrounds the pixel region E and is provided at a position overlapping the scanning line driving circuit 24 and the inspection circuit 25 in plan view. Thus, the light incident on the peripheral circuit including these drive circuits from the counter substrate 20 side is shielded, and the peripheral circuit is prevented from malfunctioning due to the light. Further, unnecessary stray light is shielded from entering the pixel region E to ensure high contrast in the display of the pixel region E.

  The planarization layer 33 is made of, for example, an inorganic material such as silicon oxide, and is provided so as to cover the light shielding portion 18 with light transmittance. As a method for forming such a planarization layer 33, for example, a method of forming a film by using a plasma CVD (Chemical Vapor Deposition) method or the like can be cited.

  The common electrode 31 is made of a transparent conductive film such as ITO (Indium Tin Oxide), for example, covers the planarization layer 33, and as shown in FIG. 1, the vertical conduction parts 26 (FIG. 1) provided at the four corners of the counter substrate 20. To the wiring on the element substrate 10 side.

  The first alignment film 28 covering the pixel electrode 27 and the second alignment film 32 covering the common electrode 31 are inorganic alignment films and are selected based on the optical design of the liquid crystal device 100. For example, a material in which an inorganic material such as SiOx (silicon oxide) is formed using a vapor phase growth method and aligned substantially perpendicularly to liquid crystal molecules can be used. As described above, the counter substrate 20 includes at least the light shielding portion 18, the common electrode 31, and the second alignment film 32.

  Such a liquid crystal device 100 is of a reflective type, and adopts an optical design of a normally black mode in which the pixel P is darkly displayed when not driven or a normally white mode in which the pixel P is brightly displayed when not driven. Depending on the optical design, a polarizing plate is disposed on the light incident side (exit side).

  As shown in FIG. 3, the liquid crystal device 100 includes a plurality of scanning lines 3 a and a plurality of data lines 6 a that are insulated and orthogonal to each other at least in the pixel region E, and a capacitor line 3 b. The direction in which the scanning line 3a extends is the X direction, and the direction in which the data line 6a extends is the Y direction.

  A pixel electrode 27, a TFT 30, and a capacitive element 16 are provided in a region divided by the scanning line 3a, the data line 6a, the capacitive line 3b, and these signal lines, and these constitute a pixel circuit of the pixel P. doing.

  The scanning line 3 a is electrically connected to the gate of the TFT 30, and the data line 6 a is electrically connected to the data line side source / drain region (source region) of the TFT 30. The pixel electrode 27 is electrically connected to the pixel electrode side source / drain region (drain region) of the TFT 30.

  The data line 6a is connected to the data line driving circuit 22 (see FIG. 1), and supplies image signals D1, D2,..., Dn supplied from the data line driving circuit 22 to the pixels P. The scanning line 3a is connected to the scanning line driving circuit 24 (see FIG. 1), and supplies the scanning signals SC1, SC2,..., SCm supplied from the scanning line driving circuit 24 to each pixel P.

  The image signals D1 to Dn supplied from the data line driving circuit 22 to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each of a plurality of adjacent data lines 6a for each group. Good. The scanning line driving circuit 24 supplies the scanning signals SC1 to SCm to the scanning line 3a in a pulse-sequential manner at a predetermined timing.

  In the liquid crystal device 100, the TFT 30 as a switching element is turned on for a certain period by the input of the scanning signals SC1 to SCm, so that the image signals D1 to Dn supplied from the data line 6a are supplied to the pixel electrode 27 at a predetermined timing. It is the structure written in. The predetermined level of image signals D1 to Dn written to the liquid crystal layer 15 through the pixel electrode 27 is held for a certain period between the pixel electrode 27 and the common electrode 31 disposed to face each other through the liquid crystal layer 15. The

  In order to prevent the retained image signals D1 to Dn from leaking, the capacitive element 16 is connected in parallel with the liquid crystal capacitance formed between the pixel electrode 27 and the common electrode 31. The capacitive element 16 is provided between the pixel electrode side source / drain region of the TFT 30 and the capacitive line 3b. The capacitive element 16 has a dielectric layer between two capacitive electrodes.

  FIG. 4 is a schematic cross-sectional view showing the structure of the liquid crystal device. Hereinafter, the structure of the liquid crystal device will be described with reference to FIG. FIG. 4 shows the cross-sectional positional relationship of each component and is expressed on a scale that can be clearly shown.

  As shown in FIG. 4, the liquid crystal device 100 includes an element substrate 10 that is one of a pair of substrates, and a counter substrate 20 that is the other of the pair of substrates disposed to face the element substrate 10. As described above, the first base material 10a constituting the element substrate 10 and the second base material 20a constituting the counter substrate 20 are constituted by, for example, a quartz substrate or a silicon substrate.

  A lower light-shielding film 3c made of titanium (Ti), chromium (Cr), or the like is formed on the first base material 10a. The lower light-shielding film 3c is planarly patterned in a lattice shape and defines an opening area of each pixel. The lower light shielding film 3c may function as a part of the scanning line 3a. A base insulating layer 11a made of a silicon oxide film or the like is formed on the first base material 10a and the lower light shielding film 3c.

  On the base insulating layer 11a, the TFT 30, the scanning line 3a, and the like are formed. The TFT 30 has, for example, an LDD (Lightly Doped Drain) structure, and includes a semiconductor layer 30a made of polysilicon or the like, a gate insulating film 11g formed so as to cover the semiconductor layer 30a, and the gate insulating film 11g. And a gate electrode 30g made of a formed polysilicon film or the like. As described above, the scanning line 3a also functions as the gate electrode 30g.

  The semiconductor layer 30a is formed as an N-type TFT 30 by implanting N-type impurity ions such as phosphorus (P) ions. Specifically, the semiconductor layer 30a includes a channel region 30c, a data line side LDD region 30s1, a data line side source / drain region 30s, a pixel electrode side LDD region 30d1, and a pixel electrode side source / drain region 30d. ing.

  The channel region 30c is doped with P-type impurity ions such as boron (B) ions. The other regions (30s1, 30s, 30d1, 30d) are doped with N-type impurity ions such as phosphorus (P) ions. Thus, the TFT 30 is formed as an N-type TFT.

  A first interlayer insulating layer 11b made of a silicon oxide film or the like is formed on the gate electrode 30g and the base insulating layer 11a. A capacitive element 16 is provided on the first interlayer insulating layer 11b. Specifically, the first capacitor electrode 16a as the pixel potential side capacitor electrode electrically connected to the pixel electrode side source / drain region 30d and the pixel electrode 27 of the TFT 30, and the capacitor line 3b (as the fixed potential side capacitor electrode). A part of the second capacitor electrode 16b) is disposed to face the dielectric layer 16c, so that the capacitor element 16 is formed.

  The capacitor line 3b (second capacitor electrode 16b) includes at least one of refractory metals such as Ti (titanium), Cr (chromium), W (tungsten), Ta (tantalum), and Mo (molybdenum). , Metal simple substance, alloy, metal silicide, polysilicide, and a laminate of these. Alternatively, it can be formed from an Al (aluminum) film.

  The first capacitor electrode 16 a is made of, for example, a conductive polysilicon film and functions as a pixel potential side capacitor electrode of the capacitor element 16. However, the first capacitor electrode 16a may be composed of a single layer film or a multilayer film containing a metal or an alloy, like the capacitor line 3b. The first capacitor electrode 16a functions as a pixel potential side capacitor electrode, and in addition to the pixel electrode 27 and the TFT 30 on the pixel electrode side via the contact hole CNT51, the contact hole CNT52, the relay layer 55, and the contact hole CNT53. It has a function of relay-connecting the region 30d (drain region).

  On the capacitive element 16, the data line 6a and the relay layer 55 are formed via the second interlayer insulating layer 11c. The data line 6a is electrically connected to the data line side source / drain region 30s (source region) of the semiconductor layer 30a through the contact hole CNT54 formed in the first interlayer insulating layer 11b and the second interlayer insulating layer 11c. Has been.

  A third interlayer insulating layer 11d is provided on the second interlayer insulating layer 11c including the data line 6a and the like. A pixel electrode 27 is provided on the third interlayer insulating layer 11d. The pixel electrode 27 is connected to the contact hole CNT51 via the contact hole CNT53, the relay layer 55, the contact hole CNT52, and the first capacitor electrode 16a, whereby the pixel electrode side source / drain region 30d (drain region) of the semiconductor layer 30a. Is electrically connected. The pixel electrode 27 is formed of a transparent conductive film such as an ITO (Indium Tin Oxide) film.

  A passivation layer 11e is provided on the pixel electrode 27 so as to cover the pixel electrode 27 and the third interlayer insulating layer 11d. The passivation layer 11e is, for example, a silicon oxide film. The upper surface of the passivation layer 11e is subjected to a planarization process such as CMP (Chemical Mechanical Polishing).

On the passivation layer 11e, a first alignment film 28 obtained by obliquely depositing an inorganic material such as silicon oxide (SiO ₂ ) is provided. On the first alignment film 28, a liquid crystal layer 15 in which an electro-optical material such as liquid crystal is sealed is provided in a space surrounded by the sealing material 14 (see FIG. 2).

On the other hand, the common electrode 31 is provided on the entire surface of the second base material 20a. On the common electrode 31 (on the lower side in FIG. 4), a second alignment film 32 obtained by oblique deposition of an inorganic material such as silicon oxide (SiO ₂ ) is provided. Similar to the pixel electrode 27 described above, the common electrode 31 is made of a transparent conductive film such as an ITO film.

  The liquid crystal layer 15 takes a predetermined alignment state by the first alignment film 28 and the second alignment film 32 in a state where an electric field from the pixel electrode 27 is not applied. The sealing material 14 is an adhesive made of, for example, a photocurable resin or a thermosetting resin, for bonding the element substrate 10 and the counter substrate 20 around them, and a distance between the two substrates is set to a predetermined value. Spacers such as glass fiber or glass beads are mixed. Hereinafter, the structure around the external connection terminal will be described in detail with reference to FIG.

  FIG. 5 is a schematic diagram showing the structure around the external connection terminal in the liquid crystal device. FIG. 5A is a schematic plan view mainly showing the structure of the external connection terminal. FIG. 5B is a schematic cross-sectional view taken along the line A-A ′ of FIG. Hereinafter, the structure around the external connection terminal will be described with reference to FIG.

  As shown in FIG. 5A, the one side portion 10b of the liquid crystal device 100 has a plurality of external connection terminals 61 (hereinafter referred to as “connection pads 61”) arranged along the one side portion 10b. Is provided. Further, as shown in FIG. 5B, on the first base material 10a of the liquid crystal device 100, as described above, the data line 6a and the relay are provided via the second interlayer insulating layer 11c such as a silicon oxide film. A layer 55 (see FIG. 4), relay layers 62 and 63, and the like are provided.

  The relay layer 62 is a metal film provided below the pixel electrode 27 a and in the same layer as the relay layer 55. Note that the pixel electrode 27a in this area is, for example, a dummy pixel electrode disposed outside the display area. On the other hand, the relay layer 63 is a metal film provided below the connection pad 61 and in the same layer as the relay layer 55.

  The relay layers 62 and 63 have a laminated structure of a titanium nitride film (TiN) and an aluminum film (Al). Specifically, first relay layers 62a and 63a made of an aluminum film are arranged on the lower side, and second relay layers 62b and 63b made of a titanium nitride film are arranged on the upper layer. The thickness of the first relay layers 62a and 63a is, for example, 500 nm. The thickness of the second relay layers 62b and 63b is, for example, 50 nm.

  A third interlayer insulating layer 11d is provided on the relay layers 62 and 63 and the second interlayer insulating layer 11c. The relay layer 62 is connected to a pixel electrode 27a provided on the third interlayer insulating layer 11d through a contact hole CNT53 provided in the third interlayer insulating layer 11d.

  The relay layer 63 is connected to a connection pad 61 provided on the third interlayer insulating layer 11d through a plug 64 provided on the third interlayer insulating layer 11d. The connection pad 61 is arranged in the same layer as the pixel electrode 27 provided in the display area, like the pixel electrode 27a.

  As shown in FIG. 5A, the plurality of plugs 64 in the region C where the connection pads 61 are formed are formed, for example, substantially parallel to the one side portion 10b. In other words, it is formed in a groove shape in plan view.

  The width D1 of the plug 64 is equivalent to the width D2 of the contact hole CNT53 connected to the pixel electrode 27 (27a), and is 0.5 μm, for example. A gap W between adjacent plugs 64 is, for example, 0.5 μm. The height of the plug 64 is, for example, 500 μm. The contact hole CNT53 and the plug 64 are made of, for example, tungsten (W).

  The connection pad 61 is made of a reflective conductive film, and has a laminated structure of a titanium film (Ti) and an aluminum film (Al), for example, like the pixel electrode 27. The thickness of the titanium film disposed on the lower side is, for example, 30 nm. The film thickness of the aluminum film disposed on the upper side is, for example, 100 nm.

A passivation layer 11e made of, for example, a silicon oxide film (SiO ₂ ) is provided on the connection pad 61 and the pixel electrode 27a so as to cover the entire surface of the third interlayer insulating layer 11d. The surface of the passivation layer 11e is subjected to a planarization process in order to improve contrast. Also, an opening 11e1 is provided above the connection pad 61 in the passivation layer 11e. Further, since the passivation layer 11e is an insulator, it is preferable that the passivation layer 11e is thin in order to reduce voltage loss.

  The connection pad 61 is used to electrically connect an FPC (Flexible Printed Circuits) terminal 66 and the liquid crystal panel 100a via an anisotropic conductive adhesive film (ACF) 65. The plug 64 provided on the lower side of the connection pad 61 absorbs the pressing force when the connection pad 61 and the FPC terminal 66 as the first electrode are crimped and connected to prevent the connection pad 61 from being destroyed. Is provided.

  In the plurality of plugs 64 described above, the gap W between the adjacent plugs 64 is preferably equal to or smaller than the diameter of the metal particles contained in the anisotropic conductive adhesive film 65.

  The diameter of the metal particles is, for example, 2 to 3 μm. The metal particles are, for example, nickel. The hardness of nickel is about 638 in terms of Vickers hardness (HV). The hardness of tungsten, which is the material of the plug 64, is harder than that of nickel and is about 3430 in terms of Vickers hardness (HV).

  In this way, when the connection pad 61 and the FPC terminal 66 are crimped and connected via the anisotropic conductive adhesive film (ACF) 65, the plug 64 is disposed on the lower side of the connection pad 61, thereby providing an anisotropic effect. It is possible to prevent the connection pad 61 from being broken through due to the metal particles contained in the conductive conductive adhesive film 65, and the connection pad 61 and the FPC terminal 66 can be electrically connected.

<Method for manufacturing liquid crystal device>
FIG. 6 is a flowchart showing a manufacturing method of the liquid crystal device in the order of steps. 7 to 11 are schematic cross-sectional views illustrating a method for manufacturing a part of the liquid crystal device. Hereinafter, a method for manufacturing the liquid crystal device will be described with reference to FIGS.

  First, a manufacturing method on the element substrate 10 side will be described. In step S11, the TFT 30 and the wiring are formed on the first base material 10a made of a glass substrate, a silicon substrate, or the like. Specifically, the TFT 30 and the like are formed on the first base material 10a by using a well-known film formation technique, photolithography technique, and etching technique.

  In step S12, the pixel electrode 27 is formed. Specifically, the pixel electrode 27 made of an ITO film or the like is formed using a known photolithography technique and etching technique. Thereafter, a passivation layer 11 e is formed on the entire substrate including the pixel electrode 27. As a film forming method, for example, a CVD method can be used. Further, a CMP polishing process is performed in order to flatten the unevenness generated on the upper surface of the passivation layer 11e.

In step S13, the first alignment film 28 is formed. Specifically, the first alignment film 28 is formed so as to cover the passivation layer 11e. As a manufacturing method of the first alignment film 28, for example, an oblique deposition method in which an inorganic material such as silicon oxide (SiO ₂ ) is obliquely deposited is used. Thus, the element substrate 10 side is completed.

  Next, a manufacturing method on the counter substrate 20 side will be described. First, in step S21, the common electrode 31 is formed on the second base material 20a made of a translucent material such as a glass substrate by using a well-known film forming technique, photolithography technique, and etching technique.

  In step S <b> 22, the second alignment film 32 is formed on the common electrode 31. The manufacturing method of the second alignment film 32 is the same as that of the first alignment film 28, and is formed using, for example, an oblique deposition method. Thus, the counter substrate 20 side is completed. Next, a method for bonding the element substrate 10 and the counter substrate 20 will be described.

  In step S <b> 31, the sealing material 14 is applied on the element substrate 10. In detail, the relative positional relationship between the element substrate 10 and the dispenser (which may be a discharge device) is changed, and the sealing material 14 is placed on the periphery of the pixel region E in the element substrate 10 (so as to surround the pixel region E). Apply.

  In step S32, the element substrate 10 and the counter substrate 20 are bonded together. Specifically, the element substrate 10 and the counter substrate 20 are bonded together via the sealing material 14 applied to the element substrate 10. More specifically, it is performed while ensuring the positional accuracy in the vertical and horizontal directions of the substrates 10 and 20.

  In step S33, liquid crystal is injected into the structure from a liquid crystal injection port (not shown), and then the liquid crystal injection port is sealed. For the sealing, for example, a sealing material such as a resin is used. Next, a manufacturing method around the external connection terminal 61 will be described with reference to FIGS. In addition, it demonstrates concretely also including the process partially overlapped with the process of the manufacturing method mentioned above.

  In the step shown in FIG. 7, the relay layers 62 and 63 are formed on the second interlayer insulating layer 11c on the element substrate 10 side. Specifically, first, the planarized second interlayer insulating layer 11c is formed on the first base material 10a using a known method. Next, the materials of the first relay layers 62a and 63a and the second relay layers 62b and 63b constituting the relay layers 62 and 63 are formed on the second interlayer insulating layer 11c. The material of the first relay layers 62a and 63a is an aluminum film. The material of the second relay layers 62b and 63b is a titanium nitride film.

  As a film forming method, for example, it can be manufactured using a CVD method or the like. Thereafter, the aluminum film and the titanium nitride film are patterned using a photolithography technique and an etching technique. As a result, a plurality of relay layers 62, 63 are formed on the second interlayer insulating layer 11c.

  In the process (plug formation process) shown in FIG. 8, the plug 64 and the contact hole CNT53 are formed. Specifically, first, a third interlayer insulating layer 11d made of a silicon oxide film or the like is formed on the entire second interlayer insulating layer 11c including the relay layers 62 and 63. As a film forming method, for example, a CVD method can be used. Thereafter, a planarization process is performed on the third interlayer insulating layer 11d.

  Next, contact holes CNT53 and plugs 64 are formed in the third interlayer insulating layer 11d using a photolithography technique and an etching technique. The plug 64 and the contact hole CNT 53 are formed at the same time by using the same etching rate. In other words, the plug 64 can be formed without adding a new manufacturing process to form the plug 64, and the number of steps can be reduced.

  Next, a tungsten film is formed on the entire surface of the substrate by using, for example, a CVD method. As a result, the tungsten film is embedded in the plug 64 and the contact hole CNT53. Thereafter, a planarization process is performed on the second interlayer insulating layer 11c by using a CMP method.

  In the step shown in FIG. 9 (connection pad forming step), the pixel electrode 27a and the connection pad 61 are formed. Specifically, first, a titanium (Ti) film is formed on the third interlayer insulating layer 11d by using, for example, a CVD method. The thickness of the titanium film is, for example, 30 nm. Next, an aluminum (Al) film is formed on the titanium film by using, for example, a CVD method. The thickness of the aluminum film is, for example, 100 nm.

  Next, the laminated film of the titanium film and the aluminum film is patterned by using a photolithography technique and an etching technique. Thereby, the pixel electrode 27a and the connection pad 61 are formed.

  In the step shown in FIG. 10, the passivation layer 11 e is formed on the third interlayer insulating layer 11 d including the pixel electrode 27 a and the connection pad 61. First, a passivation layer 11e such as a silicon oxide film is formed on the third interlayer insulating layer 11d using a CVD method or the like. Next, the unevenness generated on the surface of the passivation layer 11e is flattened by performing, for example, a CMP polishing process.

  Next, the opening 11 e 1 is formed on the connection pad 61. As a method for forming the opening 11e1, for example, it can be formed by using a photolithography technique and an etching technique.

  In the step shown in FIG. 11 (crimping step), the connection pad 61 and the FPC terminal 66 are connected. Specifically, an anisotropic conductive adhesive film 65 having metal particles 67 and an FPC terminal 66 are disposed on the liquid crystal panel 100a. Thereafter, for example, the FPC terminal 66 and the anisotropic conductive adhesive film 65 are pressed using a crimping head (not shown). Thereby, the metal particle 67 contained in the anisotropic conductive adhesive film 65 is sandwiched, and the connection pad 61 and the FPC terminal 66 are electrically connected. Thus, the liquid crystal device 100 is completed.

<Electronic equipment>
Next, a projection display device as an electronic apparatus according to the present embodiment will be described with reference to FIG. FIG. 12 is a schematic diagram showing a configuration of a reflection type projection display device including the above-described liquid crystal device.

  As shown in FIG. 12, a projection display apparatus (liquid crystal projector) 1500 as an electronic apparatus according to the present embodiment includes a polarization illumination apparatus 1100 arranged along the system optical axis L, three dichroic mirrors 1111 and 1112. 1115, two reflection mirrors 1113, 1114, reflection type liquid crystal light valves 1250, 1260, 1270 as three light modulation elements, a cross dichroic prism 1206, and a projection lens 1207.

  The polarized light illumination device 1100 is generally configured by a lamp unit 1101 as a light source composed of a white light source such as a halogen lamp, an integrator lens 1102, and a polarization conversion element 1103.

  The polarized light beam emitted from the polarization illumination device 1100 is incident on the dichroic mirror 1111 and the dichroic mirror 1112 which are arranged orthogonal to each other. A dichroic mirror 1111 serving as a light separation element reflects red light (R) in the incident polarized light flux. The dichroic mirror 1112 as the other light separation element reflects green light (G) and blue light (B) in the incident polarized light flux.

  The reflected red light (R) is reflected again by the reflection mirror 1113 and enters the liquid crystal light valve 1250. On the other hand, the reflected green light (G) and blue light (B) are reflected again by the reflection mirror 1114 and enter the dichroic mirror 1115 as a light separation element. The dichroic mirror 1115 reflects green light (G) and transmits blue light (B). The reflected green light (G) enters the liquid crystal light valve 1260. The transmitted blue light (B) enters the liquid crystal light valve 1270.

  The liquid crystal light valve 1250 includes a reflective liquid crystal panel 1251 and a wire grid polarizer 1253.

  The liquid crystal light valve 1250 is arranged so that the red light (R) reflected by the wire grid polarizer 1253 is perpendicularly incident on the incident surface of the cross dichroic prism 1206. Further, an auxiliary polarizing plate 1254 that compensates for the degree of polarization of the wire grid polarizing plate 1253 is disposed on the red light (R) incident side of the liquid crystal light valve 1250, and another auxiliary polarizing plate 1255 is disposed on the red light (R) emission side. Are arranged along the incident surface of the cross dichroic prism 1206. In the case where a polarizing beam splitter is used as the reflective polarizing element, the pair of auxiliary polarizing plates 1254 and 1255 can be omitted.

  The configuration of the reflective liquid crystal light valve 1250 and the arrangement of the components are the same in the other reflective liquid crystal light valves 1260 and 1270.

  Each color light incident on the liquid crystal light valves 1250, 1260, 1270 is modulated based on the image information, and again enters the cross dichroic prism 1206 via the wire grid polarizers 1253, 1263, 1273. In the cross dichroic prism 1206, the color lights are combined, and the combined light is projected onto the screen 1300 by the projection lens 1207, and the image is enlarged and displayed.

  In the present embodiment, the liquid crystal panel 100a in the above embodiment is applied as the reflective liquid crystal panels 1251, 1261, 1271 in the liquid crystal light valves 1250, 1260, 1270.

  According to such a liquid crystal projector 1500, since the reflective liquid crystal device 100 is used for the liquid crystal light valves 1250, 1260, and 1270, the electrical connection can be stabilized, and the reflective type having high display quality. Liquid crystal projector 1500 can be provided.

  As described above in detail, according to the liquid crystal device 100, the method for manufacturing the liquid crystal device 100, and the electronic apparatus of the present embodiment, the following effects can be obtained.

  (1) According to the liquid crystal device 100 of this embodiment, since the plug 64 is provided below the connection pad 61, the connection pad 61 and the FPC are connected via the anisotropic conductive adhesive film (ACF) 65. When the terminal 66 is crimped and electrically connected, both the connection pad 61 and the plug 64 can receive the stress. Further, the metal particles 67 can be received by the plurality of plugs 64 having a groove width equal to or smaller than the diameter of the metal particles 67 included in the anisotropic conductive adhesive film 65. Therefore, even if the connection pad 61 is destroyed, the plug 64 and the FPC terminal 66 disposed below the connection pad 61 can be reliably electrically connected.

  (2) According to the liquid crystal device 100 of the present embodiment, even if the connection pad 61 is provided in the same layer as the pixel electrode 27 having a relatively thin film thickness, the plug 64 is provided below the connection pad 61. Therefore, it is not necessary to increase the thickness of the pixel electrode 27 in order to increase the strength of the pixel electrode 27. Therefore, it is possible to prevent the surface unevenness on the substrate from becoming large as in the case where the pixel electrode 27 is thickened, and it is possible to suppress adverse effects on display quality such as contrast.

  (3) According to the method for manufacturing the liquid crystal device 100 of the present embodiment, since the connection pad 61 is formed on the plug 64, the connection pad 61 and the FPC terminal are interposed via the anisotropic conductive adhesive film 65. It is possible to receive the pressure by both the connection pad 61 and the plug 64 when the 66 is crimped and electrically connected. Further, the metal particles 67 can be received by forming a plurality of plugs 64 having a groove width equal to or smaller than the diameter of the metal particles 67 included in the anisotropic conductive adhesive film 65. Therefore, even if the connection pad 61 is destroyed, the plug 64 and the FPC terminal 66 disposed below the connection pad 61 can be reliably electrically connected.

  (4) According to the manufacturing method of the liquid crystal device 100 of the present embodiment, the plug 64 is formed simultaneously with the contact hole CNT53, so that it is not necessary to add a new manufacturing process, and the cost can be suppressed. Further, by making the width D1 of the plug 64 and the width D2 of the contact hole CNT53 the same, they can be formed simultaneously without increasing the number of steps.

  (5) According to the electronic apparatus of the present embodiment, since the liquid crystal device 100 described above is provided, an electrically stable electronic apparatus can be provided.

  The aspect of the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification. It is included in the range. Moreover, it can also implement with the following forms.

(Modification 1)
As described above, the plurality of plugs 64 is not limited to being formed substantially parallel to the one side portion 10b, and the gap W between the plugs 64 may be equal to or smaller than the diameter of the metal particles 67. The form shown in FIG. 13 may be used. FIG. 13 is a schematic plan view showing an arrangement structure of a plug 164 of a modification.

  In the liquid crystal device 200 shown in FIG. 13, the arrangement of the plurality of plugs 164 is formed substantially perpendicular to the one side portion 10b. Note that the gap between the adjacent plugs 164 and the plug 164 is, for example, the same as the gap W between the plug 64 and the plug 64 in the above-described embodiment. According to this, when the connection pad 61 and the FPC terminal 66 are crimped and electrically connected via the anisotropic conductive adhesive film 65, both the connection pad 61 and the plug 164 receive pressure. It becomes possible. Therefore, it is possible to suppress the destruction of the connection pad 61 as compared with the case of using only the connection pad 61. Thereby, the connection pad 61 and the FPC terminal 66 can be reliably electrically connected. In addition, it can be formed without increasing the number of manufacturing steps.

(Modification 2)
As described above, the plug 64 of the present embodiment is not limited to the portion of the external connection terminal 61, and may be, for example, a silver dot pad portion used for the vertical conduction portion 26 or an inspection pad portion. You may make it use.

(Modification 3)
As described above, the material of the plug 64 is not limited to using tungsten, but may be any material that is harder than nickel, which is a material of the metal particles 67 included in the anisotropic conductive adhesive film.

(Modification 4)
As described above, the plug 64 is not limited to be disposed below all of the plurality of connection pads 61. For example, even if there is a portion where the plug 64 is not disposed below the connection pad 61. Good. Specifically, for example, the plug 64 is not disposed below the connection pads 61 (constant potential supply connection pads) disposed on both sides of the connection pads 61 to which the power supply voltage is applied. As described above, since the region where the plug 64 is not disposed is provided, it is possible to suppress a short circuit (migration) that occurs when the adjacent plugs 64 come into contact with each other when the crimping connection is performed. Thereby, electrical reliability can be improved.

(Modification 5)
The electro-optical device described above is not limited to the liquid crystal device 100, and can be applied to, for example, an organic EL (Electro Luminescence) device, an electrophoresis device, and the like.

(Modification 6)
As described above, the liquid crystal device 100 is not limited to being used as a projection display device. For example, a smartphone, a mobile phone, a head mounted display, an EVF (Electrical View Finder), a small projector, a mobile computer, a digital camera, a digital video It can be used for various electronic devices such as cameras, displays, in-vehicle devices, audio devices, exposure devices, and lighting devices.

  3a ... scanning line, 3b ... capacitance line, 3c ... lower light shielding film, 6a ... data line, 10 ... element substrate, 10a ... first substrate, 10b ... one side, 11a ... underlying insulating layer, 11b ... first Interlayer insulating layer, 11c ... second interlayer insulating layer, 11d ... third interlayer insulating layer, 11e ... passivation layer, 11e1 ... opening, 11g ... gate insulating film, 14 ... sealing material, 15 ... liquid crystal layer, 16 ... capacitor element , 16a ... 1st capacitance electrode, 16b ... 2nd capacitance electrode, 16c ... Dielectric layer, 18 ... Shading part, 20 ... Opposite substrate, 20a ... 2nd base material, 22 ... Data line drive circuit, 24 ... Scanning line drive Circuit, 25 ... Inspection circuit, 26 ... Vertical conduction part, 27, 27a ... Pixel electrode, 28 ... First alignment film, 29 ... Wiring, 30 ... TFT, 30a ... Semiconductor layer, 30c ... Channel region, 30d ... Pixel electrode side Source / drain region, 30d1 ... Electrode side LDD region, 30g ... gate electrode, 30s ... data line side source / drain region, 30s1 ... data line side LDD region, 31 ... common electrode, 32 ... second alignment film, 33 ... flattening layer, CNT51, 52, 53 , 54 ... contact hole, 55 ... relay layer, 61 ... connection pad (external connection terminal), 62, 63 ... relay layer, 62a, 63a ... first relay layer, 62b, 63b ... second relay layer, 64, 164: Plug, 65: Anisotropic conductive adhesive film, 66: FPC terminal as first electrode, 67: Metal particles, 100, 200 ... Liquid crystal device, 100a ... Liquid crystal panel, 1100 ... Polarized illumination device, 1101 ... Lamp unit 1102 ... integrator lens, 1103 ... polarization conversion element, 1111, 1112, 1115 ... dichroic mirror, 1113, 1114 ... Projection mirror, 1206: Cross dichroic prism, 1207 ... Projection lens, 1250, 1260, 1270 ... Liquid crystal light valve, 1251, 1261, 1271 ... Liquid crystal panel, 1253, 1263, 1273 ... Wire grid polarizer, 1254, 1255 ... Auxiliary polarization Plate, 1300 ... screen, 1500 ... projection type display device (liquid crystal projector).

Claims (6)

A substrate,
A connection pad for electrically connecting to the first electrode via the anisotropic conductive adhesive film;
A plurality of plugs disposed between the connection pads and the substrate in contact with the connection pads;
With
The plurality of plugs are provided in a groove shape in plan view,
An electro-optical device, wherein a width between adjacent plugs of the plurality of plugs is equal to or smaller than a diameter of a metal particle included in the anisotropic conductive adhesive film. A substrate,
A plurality of reflective pixel electrodes provided on one side of the substrate corresponding to a plurality of pixels;
A connection pad provided in the same layer as the plurality of reflective pixel electrodes;
A wiring layer provided between the connection pad and the substrate;
A plurality of plugs for connecting the wiring layer and the connection pads;
The electro-optical device, wherein the plurality of plugs are formed in a groove shape along one side of the connection pad. The electro-optical device according to claim 1 or 2,
2. The electro-optical device according to claim 1, wherein the plug has a region that is not disposed in a region overlapping the connection pad for supplying a constant potential in a plan view. On the substrate, a plug forming step of forming a groove-like plug having a gap equal to or smaller than the diameter of the metal particles contained in the anisotropic conductive adhesive film,
A connection pad forming step for forming a connection pad for electrical connection with the first electrode through the anisotropic conductive adhesive film so as to be in contact with the plug on an upper layer of the plug;
Crimping the first electrode and the connection pad via the anisotropic conductive adhesive film to electrically connect the first electrode and the connection pad;
A method for manufacturing an electro-optical device. A method for manufacturing the electro-optical device according to claim 4,
A pixel electrode is connected to the substrate through a contact hole,
In the plug forming step, the plug is formed at the same time as the contact hole.   An electronic apparatus comprising the electro-optical device according to any one of claims 1 to 3.

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