JP4432589B2 - Electro-optical device, method of manufacturing electro-optical device, and electronic apparatus - Google Patents

Description

  The present invention relates to an electro-optical device such as a liquid crystal display device, an organic EL device, and a plasma display device. The present invention also relates to a manufacturing method for manufacturing the electro-optical device. The present invention also relates to an electronic apparatus configured using the electro-optical device.

  Currently, electro-optical devices such as liquid crystal display devices and EL devices are widely used in various electronic devices such as mobile phones and portable information terminals. For example, an electro-optical device is used as a display unit for visually displaying various types of information related to electronic devices. In this electro-optical device, a device using liquid crystal as an electro-optical material, that is, a liquid crystal display device is known. An EL device using EL (Electro Luminescence) as an electro-optical material is also known.

  A liquid crystal display device generally has a structure in which a liquid crystal layer is interposed between a pair of substrates each having an electrode. The liquid crystal layer is formed by forming a space surrounded by a sealing material between the pair of substrates and sealing the liquid crystal inside the space. The liquid crystal display device supplies light to the liquid crystal layer and controls the orientation of liquid crystal molecules in the liquid crystal layer for each display dot by controlling the voltage applied to the liquid crystal layer for each display dot. The light supplied to the liquid crystal layer is modulated according to the alignment state of the liquid crystal molecules, and images such as letters, numbers, figures, etc. are displayed depending on whether the modulated polarized light passes through the polarizing plate or not. Is done.

  In this liquid crystal display device, a plurality of wirings are formed on one or both of a pair of substrates in order to transmit a signal to each electrode. Many of these wirings are disposed over the inside and outside of the sealing material that seals the liquid crystal. As the wiring material, for example, Cr (chromium), Mo (molybdenum), Al (aluminum), Ti (titanium), or the like is used. These are low-resistance materials and are preferably used as wiring materials. However, these low-resistance materials are easily corroded by moisture and dirt, and there is a possibility that the display of the liquid crystal display unit may be damaged when corroded.

  In order to solve this problem, conventionally, wiring disposed outside the sealing material, that is, a corrosion-resistant material, for example, Ta (tantalum) or ITO (Indium Tin Oxide) is used as a material constituting the outer wiring, There is known a liquid crystal display device having a structure in which an outer layer wiring is hardly corroded by stacking an oxide film thereon. In this liquid crystal display device, the inner wiring disposed inside the sealing material has a structure in which a low-resistance material is further laminated on the same material as the outer wiring (see, for example, Patent Document 1). ). According to this conventional wiring structure, the outer wiring that is easily corroded is formed of a corrosion-resistant material, and the inner wiring that is inside the sealing material and has no fear of being corroded is formed of a low-resistance material. It was expected that a wiring structure excellent in both resistance and low resistance could be obtained.

JP 2001-75118 A (page 4, FIG. 1)

  However, the conventional wiring structure using the corrosion-resistant material disclosed in Patent Document 1 inevitably occurs in the manufacturing process of the oxide film or the liquid crystal display substrate positively provided on the corrosion-resistant material. The oxide film may increase the connection resistance between the corrosion-resistant material and the low-resistance material in the inner wiring. As a result, display unevenness may occur in the display unit of the liquid crystal display device, or power consumption of the liquid crystal display device may increase.

  The present invention has been made in view of the above problems, and provides an electro-optical device having a wiring structure having both corrosion resistance and low resistance, a method for manufacturing the electro-optical device, and an electronic apparatus. With the goal.

  An electro-optical device according to the present invention includes an electro-optical material provided inside a sealing material, an inner wiring provided inside the sealing material, and an outer wiring provided outside the sealing material. In the optical device, the inner wiring has a laminated structure in which an insulating material is formed on a corrosion-resistant material and a low-resistance material is formed thereon, and the outer wiring has a corrosion-resistant material, A part or all of the side surface of the inner wiring has a portion where the corrosion-resistant material and the low-resistance material are in direct contact with each other due to the absence of the insulating material.

  According to the above electro-optical device, the use of the corrosion-resistant material for the outer wiring can prevent the wiring from being corroded due to adhesion of moisture and dirt. Further, by providing a portion in the inner wiring where the corrosion resistant material and the low resistance material are in direct contact, the wiring resistance can be reliably reduced. Accordingly, stable display without display unevenness can be performed in the electro-optical device.

  In the electro-optical device according to the aspect of the invention, it is preferable that a portion where the corrosion-resistant material and the low-resistance material are in direct contact is a tapered surface. As a result, the contact area between the corrosion-resistant material and the low-resistance material can be increased. As a result, the wiring resistance can be further reduced.

  In the electro-optical device according to the aspect of the invention, it is preferable that the corrosion-resistant material is Ta (tantalum) or Ta (tantalum) alloy. These materials are superior in corrosion resistance compared to low-resistance materials, and can form wirings that are less susceptible to corrosion.

  In the electro-optical device according to the aspect of the invention, the low-resistance material is selected from Cr (chromium), Mo (molybdenum), Al (aluminum), Ti (titanium), or an alloy mainly containing one of them. It is desirable to have one. These materials are excellent in conductivity and can reduce wiring resistance.

  In the electro-optical device according to the aspect of the invention, it is preferable that the inner wiring and the outer wiring form a continuous wiring extending across the sealing material. By forming the continuous wiring, it is possible to avoid a failure such as a contact failure in the connection portion between the outer wiring and the inner wiring.

  The electro-optical device of the present invention preferably further includes an electrode for applying a voltage to the electro-optical material, and the inner wiring is connected to the electrode. By doing so, the inner wiring can be used as a scanning line or a data line when supplying a scanning signal or a data signal to the electrodes. According to the present invention, the inner wiring can have a low resistance, so that a data signal or the like can be normally supplied to the electrodes.

  In the electro-optical device according to the aspect of the invention, in the inner wiring, a contact hole is provided in a layer made of the corrosion-resistant material and the insulating material, and the low-resistance material enters the contact hole and directly contacts the corrosion-resistant material. It is desirable to contact Thus, by providing a portion where the corrosion resistant material and the low resistance material are in direct contact with each other on the portion other than the side surface of the wiring, the wiring resistance can be further reduced. Accordingly, it is possible to perform stable display without display unevenness in the electro-optical device.

  In the electro-optical device in which the contact hole is provided, it is preferable that the inner wiring has a conductive pad portion that contacts conductive particles inside the sealing material, and the contact hole is provided in the conductive pad portion. This conductive pad portion has a wider wiring width than other portions of the inner wiring. Therefore, a plurality of contact holes or large contact holes can be provided in the conductive pad portion. As a result, the contact area between the corrosion resistant material and the low resistance material can be increased, and the wiring resistance can be reduced. Further, since the conductive pad portion is a portion sandwiched from both sides by the substrate and the sealing material, the corrosion-resistant material and the low-resistance material can surely come into contact with each other.

  Next, another electro-optical device according to the present invention includes a pair of substrates bonded together with a sealing material, a liquid crystal sealed in a region surrounded by the sealing material and the pair of substrates, and the pair of substrates. An electro-optical device having an electrode provided on each surface and inside the sealing material, and a wiring extending from the electrode and extending to the outside of the sealing material, and the inside of the sealing material among the wirings The inner wiring located in the layer has a laminated structure in which an insulating material is formed on a corrosion-resistant material and a low resistance material is formed thereon, and the outer wiring located outside the sealing material among the wiring is It has a corrosion-resistant material, and a part or all of the side surface of the inner wiring has a portion where the corrosion-resistant material and the low-resistance material are in direct contact due to the absence of the insulating material. To do.

  This electro-optical device is a display device using liquid crystal as an electro-optical material, that is, a liquid crystal display device. According to this electro-optical device, corrosion resistance due to adhesion of moisture or dirt can be prevented by using a corrosion-resistant material for the outer wiring. Further, by providing a portion in the inner wiring where the corrosion resistant material and the low resistance material are in direct contact, the resistance of the wiring can be reliably reduced. Accordingly, it is possible to perform stable display without display unevenness in the electro-optical device.

  Next, the method for manufacturing an electro-optical device according to the present invention includes a step of forming a sealing material on a substrate, a step of providing an electro-optical material inside the sealing material, and both sides inside and outside the sealing material. A method of manufacturing the electro-optical device, the step of forming the wiring comprising: forming a first layer made of a corrosion-resistant material inside the sealing material; and A step of forming a second layer made of an insulating material on the substrate, an etching step of removing a part or all of side surfaces of the wiring formed by stacking the first layer and the second layer by etching, Forming a third layer with a low resistance material on the two layers. The second layer may be formed positively with an insulating material, or may be formed with an oxide film inevitably generated in the manufacturing process of the substrate for a liquid crystal display device.

  According to the above method for manufacturing an electro-optical device, the outer wiring is formed using a corrosion-resistant material, thereby preventing the wiring from being corroded due to adhesion of moisture or dirt. Further, in the inner wiring, the first layer is formed with a corrosion-resistant material, the second layer is formed with an insulating material, and then the second layer or both the first layer and the second layer are removed by etching. The surface of the 1st layer which is a property material is exposed. Further, a third layer made of a low resistance material is formed on the second layer. Thereby, the corrosion-resistant material exposed by etching and the low-resistance material can be in direct contact with each other without the insulating material. Therefore, the resistance of the wiring can be reliably reduced. As a result, it is possible to perform stable display without display unevenness in the electro-optical device.

  In the method of manufacturing an electro-optical device according to the aspect of the invention, it is preferable that in the etching process, side surfaces of the first layer and the second layer are formed into tapered surfaces. Thereby, the contact area of the corrosion-resistant material of the first layer and the low-resistance material of the third layer can be increased. As a result, the wiring resistance can be further reduced.

  In the method of manufacturing the electro-optical device according to the aspect of the invention, in the step of forming the third layer, the third layer is formed inside and outside the sealing material, and then the third layer is removed outside the sealing material. It is desirable to do. According to this method of manufacturing an electro-optical device, even if a foreign object is placed on a plurality of outer wirings, it is safe without causing a short circuit between the plurality of wirings provided on the substrate. .

  Next, an electronic apparatus according to the present invention includes the electro-optical device having the above-described configuration. Since the electro-optical device according to the present invention has a wiring structure having both corrosion resistance and low resistance, it is possible to perform stable display without display unevenness. Therefore, even in an electronic apparatus using the electro-optical device according to the present invention, a stable display can be performed without display unevenness.

(Embodiment of electro-optical device)
Hereinafter, a case where the present invention is applied to a liquid crystal display device which is an example of an electro-optical device will be described as an example. In addition, embodiment described below is an example of this invention, Comprising: This invention is not limited. In the following description, the drawings will be referred to as necessary. In this drawing, in order to show the important components of the structure composed of a plurality of components in an easy-to-understand manner, the relative dimensions differ from actual ones. Is shown.

  FIG. 1 shows a liquid crystal display device which is an embodiment of an electro-optical device according to the present invention. FIG. 2 shows an enlarged view of the vicinity of one display dot in FIG. The liquid crystal display device described here is an active matrix type using a TFD (Thin Film Diode) element which is a two-terminal switching element, and is a transflective liquid crystal display device.

  In FIG. 1, the liquid crystal display device 1 includes a liquid crystal panel 2, a driving IC 3 mounted on the liquid crystal panel 2, and an illumination device 4. The illumination device 4 is disposed on the back side of the liquid crystal panel 2 when viewed from the observation side (that is, the upper side in the figure) and functions as a backlight. The illumination device 4 may be disposed on the observation side of the liquid crystal panel 2 and function as a front light.

  The illuminating device 4 includes a light source 6 constituted by a point light source such as an LED (Light Emitting Diode), a linear light source such as a cold cathode tube, and the like, and a light guide body 7 formed of a translucent resin. Have. A reflective layer 8 is provided on the back side of the light guide 7 as viewed from the observation side, if necessary. A diffusion layer 9 is provided on the observation side of the light guide 7 as necessary. The light entrance 7a of the light guide 7 extends in the direction perpendicular to the paper surface of FIG. 1, and light generated from the light source 6 is introduced into the light guide 7 through the light entrance 7a.

  The liquid crystal panel 2 includes an element substrate 12, a color filter substrate 11 facing the element substrate 12, and a square or rectangular frame-shaped sealing material 13 as viewed from the direction of arrow A to which the substrates are bonded. Liquid crystal 14 as an electro-optical material is sealed in a gap surrounded by the color filter substrate 11, the element substrate 12, and the sealing material 13, a so-called cell gap G, to form a liquid crystal layer.

  The color filter substrate 11 has a rectangular or square first base material 16a when viewed from the direction of arrow A, and a resin layer having a combination of unevenness, that is, a concave portion and a non-recessed portion, on the inner surface of the first base material 16a. 17 is formed, a reflective layer 18 is formed thereon, a plurality of coloring elements 19 and a light shielding member 21 surrounding them are formed, an overcoat layer 22 is formed thereon, and a paper surface perpendicular to the paper surface is formed thereon. A plurality of electrodes 23a linearly extending in the direction are formed, and an alignment film 24a is further formed thereon.

  The alignment film 24a is subjected to an alignment process such as a rubbing process, whereby the alignment of liquid crystal molecules in the vicinity of the color filter substrate 11 is determined. Moreover, the phase difference plate 26a and the polarizing plate 27a are attached to the outer surface of the first base material 16a by sticking or the like. The first base material 16a is made of, for example, translucent glass, translucent plastic, or the like.

  In FIG. 2, the resin layer 17 is formed by a two-layer structure including a first layer 17a and a second layer 17b, and fine irregularities, that is, fine recesses and non-recesses are formed on the surface of the second layer 17b. ing. The reflective layer 18 is made of, for example, Al, an Al alloy, or the like. The surface of the reflective layer 18 has a concavo-convex shape corresponding to the undulations attached to the resin layer 17 that is the underlying layer. Due to this uneven shape, the light reflected by the reflective layer 18 diffuses.

  For example, each of the coloring elements 19 is formed in a rectangular dot shape, and one coloring element 19 exhibits any one of the three primary colors of R (red), G (green), and B (blue). . The coloring elements 19 of these colors are arranged so as to form a stripe arrangement, a delta arrangement, a mosaic arrangement, and other appropriate arrangements when viewed from the direction of the arrow A. The coloring element 19 can also be formed by three primary colors of C (cyan), M (magenta), and Y (yellow).

  The light shielding member 21 is formed so as to fill a space between the plurality of coloring elements 19 with a light shielding material such as Cr. The light shielding member 21 functions as a black matrix and improves the contrast of an image displayed by light transmitted through the coloring elements 19. The light shielding member 21 is not limited to being formed of a specific material such as Cr, and may be formed by, for example, stacking, that is, stacking, R, G, and B coloring elements constituting the coloring element 19. can do.

  The overcoat layer 22 is formed of a photosensitive resin such as an acrylic resin or a polyimide resin. The plurality of electrodes 23a extending linearly in the direction perpendicular to the paper surface of FIG. 2 are formed of a metal oxide such as ITO. Further, the alignment film 24a formed thereon is formed of polyimide or the like, for example.

  In FIG. 1, the element substrate 12 facing the color filter substrate 11 has a second base material 16b. In the second base material 16b, one side where the projecting portion 29 is formed projects to the outside of the first base material 16a. As shown in FIG. 2, line wiring 33 is formed on the inner surface of the second base material 16 b, and a plurality of TFD elements 31, which are nonlinear resistance elements functioning as switching elements, are connected to the line wiring 33. It is formed. Further, a plurality of dot electrodes 23 b are formed so as to be connected to those TFD elements 31. The line wiring 33 extends in a direction perpendicular to the linear electrode 23a on the color filter substrate 11, that is, in the left-right direction in FIG.

  A plurality of photo spacers 15 are formed between the dot electrodes 23b, and an alignment film 24b is formed thereon. These photo spacers 15 are formed, for example, by patterning a photosensitive resin by a photolithography process. The photo spacer 15 is formed in a standing cylindrical shape and functions so that the cell gap maintains a uniform dimension. The photo spacer 15 may be called a gap material. The alignment film 24b is subjected to an alignment process such as a rubbing process, whereby the alignment of liquid crystal molecules in the vicinity of the element substrate 12 is determined. A phase difference plate 26b and a polarizing plate 27b are attached to the outer surface of the second base material 16b by sticking or the like.

  The second base material 16b is made of, for example, translucent glass, translucent plastic, or the like. The dot electrode 23b is formed of a metal oxide such as ITO. The alignment film 24b is formed of, for example, polyimide.

  Each TFD element 31 is provided at a position corresponding to the light shielding member 21 on the color filter substrate 11 side. Further, as shown in FIG. 3, the first TFD element 32a and the second TFD element 32b are connected in series. Is formed.

  In FIG. 3, the TFD element 31 is formed as follows, for example. That is, first, the first layer 42 of the line wiring 33 and the first metal 36 of the TFD element 31 are formed by TaW. Next, the second layer 43 of the line wiring 33 and the insulating film 37 of the TFD element 31 are formed by anodizing treatment. Next, the third layer 41 of the line wiring 33 and the second metal 38 of the TFD element 31 are formed by using, for example, Cr.

  The second metal 38 of the first TFD element 32 a extends from the third layer 41 of the line wiring 33. Further, the dot electrode 23b is formed so as to overlap the tip of the second metal 38 of the second TFD element 32b. Considering that an electric signal flows from the line wiring 33 toward the dot electrode 23b, the electric signal flows in the order of the second electrode 38 → the insulating film 37 → the first metal 36 in the first TFD element 32a according to the current direction. In the second TFD element 32b, electrical signals flow in the order of the first metal 36 → the insulating film 37 → the second metal 38.

  That is, a pair of electrically opposite TFD elements are connected in series between the first TFD element 32a and the second TFD element 32b. Such a structure is generally called a back-to-back structure, and the TFD element of this structure is compared with a case where the TFD element is configured by only one TFD element. It is known that stable characteristics can be obtained. In order to prevent the first metal 36 and the like from peeling off from the second base material 16b, and to prevent impurities from diffusing from the second base material 16b to the first metal 36 and the like, the TFD element 31 and An underlayer (not shown) can also be provided between the base material 16b and between the line wiring 33 and the base material 16b.

  FIG. 4 shows the planar structure of the liquid crystal display device 1 when the liquid crystal display device 1 of FIG. 1 is viewed from the direction of the arrow A and the second base material 16b is not shown. FIG. 5 shows the planar structure of the element substrate 12 in a state where the element substrate 12 of FIG. 1 is viewed from the direction of arrow A and the second base material 16b is not shown. FIG. 6 shows a planar structure of the color filter substrate 11 when the color filter substrate 11 of FIG. 1 is viewed from the direction of the arrow A. 4, 5, and 6 mainly show electrodes and wiring, and other elements are not shown.

  As shown in FIG. 5, the plurality of linear line wirings 33 provided on the element substrate 12 are provided in a stripe shape as a whole. The plurality of TFD elements 31 are connected to the individual line wirings 33 at appropriate intervals, and the dot electrodes 23 b are connected to the TFD elements 31. In FIG. 5, the line wiring 33 is schematically drawn with a small number, but in practice, a large number, for example, about 240 are formed. In addition, although the TFD element 31 and the dot electrode 23 b are only partially shown corresponding to the four corners of the sealing material 13, they are actually provided in the entire region surrounded by the sealing material 13. Further, since the TFD element 31 and the dot electrode 23b are schematically drawn large, they are drawn so as to have a small number, but actually, in the vertical direction of FIG. For example, about 320 are formed. That is, the dot electrode 23b is provided by the number of vertical x horizontal = 320 x 240, for example.

  In FIG. 1, the plurality of linear electrodes 23a provided on the color filter substrate 11 facing the element substrate 12 are formed in a stripe shape as a whole as shown in FIG. As shown in FIG. 4, these linear electrodes 23 a extend in a direction perpendicular to the line wiring 33 when the color filter substrate 11 and the element substrate 12 are bonded to each other with the sealing material 13, and are further formed in a plurality of rows. The dot electrode 23b overlaps in a planar manner. Thus, the area where the linear electrode 23a and the dot electrode 23b overlap constitutes a display dot area which is the minimum unit of display. This display dot region is a region indicated by a symbol D in FIGS. A display region V is a region where a plurality of display dot regions D are arranged in a matrix in the vertical and horizontal directions. Images such as letters, numbers, figures, etc. are displayed in the display area V.

  In FIG. 5, the driving IC 3 mounted on the overhanging portion 29 of the second base material 16b constituting the element substrate 12 includes a driving IC 3a that outputs a scanning signal and a driving IC 3b that outputs a data signal. Has been. External connection terminals 44 are formed on the first side 16c of the second base material 16b, that is, the input side, and these terminals 44 are connected to input terminals of the driving ICs 3a and 3b, for example, input bumps.

  A wiring board (not shown) such as a flexible wiring board is connected to the external connection terminal 44 by a conductive connection method such as soldering, ACF (Anisotropic Conductive Film), heat sealing, or the like. Signals, power, and the like are supplied to the liquid crystal display device 1 from an electronic device such as a mobile phone or a portable information terminal via the wiring board.

  A plurality of wirings 49 are formed in the vicinity of the two sides 16d and 16e adjacent to the first side 16c along the sides. These wirings 49 are continuous wirings that cross the sealing material 13 from the output terminals of the driving IC 3a, for example, the output bumps, and further extend toward the second side 16f facing the first side 16c. Each wiring 49 is constituted by a main line portion 49a parallel to each of the two sides 16d and 16e, and a portion 49b that bends toward the outside of the sealing material 13 at approximately 90 °. Further, the line wiring 33 formed on the element substrate 12 is connected to an output terminal of the driving IC 3 b, for example, an output bump, across the sealing material 13.

  In FIG. 2, an opening 46 is provided in the reflective layer 18 corresponding to each display dot region D. These openings 46 are formed in a rectangular shape when viewed in plan from the direction of arrow A. When color display is performed using the coloring elements 19 composed of the three colors R, G, and B as in the present embodiment, the three corresponding to the three coloring elements 19 corresponding to the three colors R, G, and B are used. One display dot region D forms one pixel. On the other hand, when monochrome display is performed in black and white or any one color, one pixel is formed by one display dot region D.

  In FIG. 2, a portion R where the reflective layer 18 is provided in each display dot region D is a reflective portion, and a portion T where the opening 46 is formed is a transmissive portion. External light incident from the observation side, that is, external light L0 incident from the element substrate 12 side is reflected by the reflection portion R. On the other hand, the light L1 emitted from the light guide 7 of the illumination device 4 in FIG.

  Hereinafter, the operation of the liquid crystal display device 1 of the present embodiment will be described. In FIG. 2, when external light such as sunlight or room light is strong, external light L <b> 0 is reflected by the reflection portion R and supplied to the liquid crystal layer 14. Thereby, reflective display is performed. On the other hand, when the illuminating device 4 in FIG. 1 is turned on, the planar light emitted from the light guide 7 is supplied to the liquid crystal layer 14 through the transmission portion T in FIG. Thereby, transmissive display is performed. By selecting and executing such a reflective display and a transmissive display as desired, a transflective display is performed.

  In this embodiment, a scanning signal is applied to the linear electrode 23a, which is one of the linear electrode 23a and the dot electrode 23b that sandwich the liquid crystal layer 14. On the other hand, in the present embodiment, a data signal is applied to the other of the linear electrode 23a and the dot electrode 23b. The TFD element 31 attached to the display dot region D to which the scanning signal and the data signal are applied is turned on, and the alignment state of the liquid crystal molecules in the display dot region D modulates the light passing through the display dot region D. Maintained. Then, depending on whether or not the modulated light passes through the polarizing plate 27b of FIG. 1, a desired image such as letters, numbers, and figures is displayed on the outside of the element substrate 12. The case where the display is performed using the external light L0 is the reflection type display, and the case where the display is performed using the transmitted light L1 is the transmission type display.

  In the liquid crystal display device according to the present embodiment, in FIG. 5, the wiring 49 includes a portion located inside the sealing material 13, that is, an inner wiring 49 c and a portion located outside the sealing material 13, that is, the outer wiring 49 d. Have. The line wiring 33 also includes an inner wiring 33 c that is a portion located inside the sealing material 13 and an outer wiring 33 d that is a portion located outside the sealing material 13. In addition, the wiring of the part which overlaps with the sealing material 13 is an inner wiring.

  The outer wirings 33d and 49d and the inner wirings 33c and 49c form one continuous continuous wiring. If a configuration in which the outer wiring and the inner wiring are separate wirings and are conductively connected by a conductive material, connection failure may occur in the conductive connection portion. On the other hand, if the outer wiring and the inner wiring are one wiring, there is no fear of such a connection failure.

  FIG. 7 is an enlarged view of the area indicated by the arrow B in FIG. As shown in FIG. 7, a conduction pad 48 is formed at the tip of the bent portion 49b of the inner wiring 49c. In the main line portion 49a, the line width and the wiring interval are relatively narrow. On the other hand, the line width of the bent portion 49b and the conductive pad portion 48 is wider than that of the main line portion 49a.

  In FIG. 4, a spherical or cylindrical conducting material 54 is contained in an irregularly dispersed state inside the sealing material 13. When the element substrate 12 shown in FIG. 5 and the color filter substrate 11 shown in FIG. 6 are bonded together as shown in FIG. 4, the conductive pads 48 on the element substrate 12 side (see FIG. 7) and the color filter substrate 11 side The end portion of the linear electrode 23 a is electrically connected by the conductive material 54. Thereby, the electrode 23a on the color filter substrate 11 side is electrically connected to the driving IC 3a through the wiring 49 on the element substrate 12 side.

  The conduction between the linear electrode 23a and the wiring 49 is realized alternately between the left side and the right side in FIG. However, instead of this, a driving method in which the upper half of the display region V is conducted on one of the left side and the right side, and the lower half of the display region V is conducted on the other side of the left side and the right side. It can also be adopted.

  FIG. 8 is an enlarged view of the area indicated by the arrow C in FIG. That is, FIG. 8 shows a structure on the other end side of the wiring structure shown in FIG. As shown in FIG. 8, an IC connection terminal 47 is formed at each end portion of the plurality of outer wirings 49 d disposed outside the sealing material 13. The driving IC 3 is mounted on these IC connection terminals 47 by, for example, the ACF 53 on the overhanging portion 29 of the element substrate 12 of FIG.

  The ACF 53 is formed by dispersing conductive particles inside a thermosetting resin or an ultraviolet curable resin. The main body portion of the driving IC 3 is fixed on the protruding portion 29 of the substrate by a thermosetting resin or the like. Further, the output bump of the driving IC 3 and the IC connection terminal 47 are conductively connected to each other by the conductive particles contained in the ACF 53, and the input bump of the driving IC 3 and the external connection terminal 44 are connected.

  FIG. 9A shows a cross section of the wiring 49 along the line EE of FIG. 8, that is, a cross section of the outer wiring 49d of FIG. The outer wiring 49d is a laminate in which the first layer 42 is formed of TaW as a corrosion-resistant material on the second base material 16b, and the second layer 43 is formed of TaOx (tantalum oxide) as an insulating material thereon. It has a structure.

  Since the outer wiring 49d is located outside the sealing material 13, moisture and dirt are more likely to adhere to the inner wiring 49c. That is, the outer wiring 49d is in an environment that is more easily corroded than the inner wiring 49c. By the way, considering that the wiring resistance is lowered, a low resistance material such as Cr is preferably used as the wiring material. However, Cr is easily corroded by moisture and dirt. When the wiring is corroded, the display resistance of the liquid crystal display device may be uneven due to a change in the resistance value of the wiring or disconnection of the wiring.

  In this embodiment, the outer wiring 49d has a laminated structure of TaW which is a corrosion resistant material and TaOx which is also a corrosion resistant material. As a result, the outer wiring 49d is less likely to be corroded than when a low resistance material such as Cr is used. As a result, it is possible to suppress the occurrence of display unevenness in the display unit of the liquid crystal display device.

  Next, in FIG. 8, the inner wiring 49 c has a portion with the second layer 43 and a portion without the second layer 43 on the side surface. The portion indicated by the FF line is a portion where the second layer 43 is present, and the portion indicated by the HH line is a portion where the second layer 43 is not present. A portion where the second layer 43 is not formed is also formed in a bent portion 49b shown by a line II in FIG.

  FIG. 9B shows a cross section of a portion where the second layer 43 of the inner wiring 49c is present along the line FF in FIG. The inner wiring 49c of this portion has the same laminated structure as the outer wiring, that is, a laminated structure in which the third layer 41 is further formed on the first layer 42 and the second layer 43 by Cr as a low resistance material. Since the inner wiring 49c is inside the sealing material 13, it is not affected by moisture or dirt. Therefore, the inner wiring 49c is hardly corroded even if the wiring is formed using Cr which is a low resistance material. If Cr is used in this way, the resistance of the inner wiring 49c, and thus the entire wiring 49, can be lowered.

  The inner wiring 49c and the outer wiring 49d can be formed simultaneously with the formation of the TFD element 31 of FIG. That is, in FIG. 3, the first layer 42 is formed simultaneously with the formation of the first metal 36 of the TFD element 31, and the second layer 43 is formed simultaneously with the formation of the insulating film 37 of the TFD element 31. Further, the third layer 41 can be formed simultaneously with the formation of the second metal 38 of the TFD element 31.

  FIG. 10A shows a cross section taken along line HH in FIG. 8 and line II in FIG. In these portions of the inner wiring 49c, the second layer 43 on the side surface of the wiring is removed by etching. The etching at this time may be etching that removes the second layer 43 and exposes the surface of the first layer 42, or digs into the surface portion of the first layer 42 together with the second layer 43. Etching may be used. When etching is performed so that the surface portion of the first layer 42 is also dug down, as shown by the broken line Q in FIG. It is formed on the side surface of one layer 42. In the present embodiment, the side surface of the first layer 42 itself is a tapered surface. Therefore, when only the second layer 43 is removed by etching, the side surface of the first layer 42 exposed thereafter is a tapered surface. Become. On the other hand, the side surface of the first layer 42 is not a tapered surface but can be an upright surface, that is, a surface standing at an angle of approximately 90 °. In this case, when only the second layer 43 is removed by etching, the side surface of the exposed first layer 42 is not a tapered surface but an upright surface.

  The side surface portion of the first layer 42 exposed by etching constitutes a contact surface 51 with respect to the third layer 41. The first layer 42 and the third layer 41 are in direct contact with each other at the contact surface 51. As a result, the wiring resistance can be reliably reduced, and display unevenness can be prevented from occurring in the display portion of the liquid crystal display device. In addition, by making the contact surface 51 a tapered surface, the contact area can be increased, and in this case, the reliability with which the wiring resistance can be lowered can be further increased.

  FIG. 10B shows a cross-sectional structure of the IC connection terminal 47 and the conduction pad 48 along the line LL in FIG. 8 and the line KK in FIG. In these IC connection terminal 47 and conduction pad 48, a conductive hole, that is, a contact hole 52 is formed by etching before the third layer 41 is formed. In FIG. 10B, the first layer 42 is exposed to the outside on the inner peripheral surface of the contact hole 52, and this exposed surface constitutes a contact surface 51 for the third layer 41. In the present embodiment, the contact surface 51 is a tapered surface, but this can also be an upright surface. In the contact surface 51 formed in this way, the third layer 41 and the first layer 42 are in direct contact. As a result, the wiring resistance can be lowered, and display unevenness hardly occurs in the liquid crystal display unit. Moreover, by making the contact surface 51 into a taper surface, a contact area can be taken large and wiring resistance can be made lower.

  The main line portion 49a and the bent portion 49b of the wiring 49 shown in FIG. 5 have a very narrow width. Therefore, it is very difficult to form a contact hole in the internal region of the wiring. However, the IC connection terminal 47 of FIG. 8 and the conductive pad 48 of FIG. 7 have a wider wiring width than other wiring portions. Therefore, a plurality of contact holes 52 or large contact holes 52 can be provided without difficulty. Thereby, the area of the contact part 51 of the 3rd layer 41 and the 1st layer 42 can be taken large, As a result, wiring resistance can be made lower.

  As shown in FIG. 1, the IC connection terminal 47 is sandwiched between the second base material 16b and the driving IC 3 from both sides. Further, as understood from FIG. 7, the conduction pad 48 is sandwiched between the second base material 16 b and the sealing material 13 from both sides. Therefore, if the contact hole 52 is provided in the IC connection terminal 47 and the conduction pad 48, the first layer 42 and the third layer 41 are securely connected by the action of the clamping force when sandwiched from both sides. Can be contacted.

  The IC connection terminal 47 in FIG. 8 and the conduction pad 48 in FIG. 7 further have an ITO film 45 on the third layer 41 as shown in FIG. By providing the ITO film 45, good electrical connection can be obtained between the conductive material contained in the ACF 53 used for connection of the driving IC 3. Similarly, a good electrical connection can be obtained between the element substrate 12 and the color filter substrate 11 in FIG.

  The etching performed on the wiring side surface in FIG. 10A and the etching for forming the contact hole 52 shown in FIG. 10B are simultaneously performed when the TFD element 31 in FIG. 3 is formed on the element substrate 12. be able to. When the TFD element 31 of FIG. 3 is formed, for example, the first metal 36 is initially formed in a shape connected to the first layer 42 of the line wiring 33, and the first metal 36 is passed through the first layer 42. Then, an anodic oxidation treatment is performed by flowing a current to the first layer 42 and the first metal 36 to form an anodic oxide film, that is, an insulating film 37. Thereafter, the stacked portion of the first layer 42 and the second layer 43 of the line wiring 33 and the stacked portion of the first metal 36 and the insulating film 37 of the TFD element 31 are separated by etching. Then, the second metal 38 is stacked on the separated insulating film 37. Etching for the contact hole 52 in FIG. 10B and etching performed on the wiring side surface in FIG. 10A separates the first metal 36 and the insulating film 37 when the TFD element 31 is formed. Can be performed simultaneously with etching.

  As described above, the structure of the wiring 49 described with reference to FIGS. 5, 7, 8, 9, and 10 can be applied to the line wiring 33 of FIG. 5. That is, as shown in FIG. 9A, the outer wiring 33d of the line wiring 33 can be configured by stacking the second layer 43, which is also a corrosion-resistant material, on the first layer 42, which is a corrosion-resistant material. . If the outer wiring 33d is formed of a corrosion-resistant material, the wiring can be prevented from being corroded.

  Further, as shown in FIG. 9B and FIG. 10A, the inner wiring 33c of the line wiring 33 in FIG. 5 is formed of a low resistance material on the first layer 42 and the second layer 43. Three layers 41 are stacked. Thereby, wiring resistance can be made low.

  Further, the inner wiring 33c of the line wiring 33 includes a portion where the second layer 43 is present on the entire surface of the first layer 42 as shown in FIG. 9B and a first wiring as shown in FIG. The second layer 43 is not provided on the side surface of the layer 42, and two portions are provided, that is, a portion where the first layer 42 and the third layer 41 are in direct contact. By providing a portion in which the first layer 42 and the third layer 41 are in direct contact without the second layer 43, the electrical connection between the first layer 42 and the third layer 41 is reliably ensured. Can do.

  Further, as shown in FIG. 8, the line connection 33 can be provided with an IC connection terminal 47 at its tip, and further, a contact hole 52 can be provided inside the IC connection terminal 47. Then, as shown in FIG. 10B, electrical conduction between the first layer 42 and the third layer 41 can be achieved through the contact hole 52. In this way, the electrical connection between the first layer 42 and the third layer 41 can be more reliably ensured.

  As described above, in the present embodiment, as shown in FIG. 5, the wirings 33 and 49 are provided on the second base material 16 b constituting the element substrate 12. In these wirings 33 and 49, the wiring located outside the sealing material 13 may be corroded under the influence of moisture and dirt. When the wiring is corroded, the resistance value of the wiring is changed or the wiring is disconnected, which may cause display unevenness in the display portion of the liquid crystal display device. On the other hand, in the present embodiment, since the outer wirings 33d and 49d located outside the sealing material 13 are formed of a corrosion-resistant material, the outer wirings 33d and 49d are hardly corroded. As a result, display unevenness can be prevented from occurring in the liquid crystal display unit.

  Further, the lengths of the wirings 33 and 49 vary depending on the position of the conductive electrode. When the wirings 33 and 49 become longer, the wiring resistance becomes larger than when the wirings 33 and 49 are shorter. Display unevenness may occur due to the difference in wiring resistance. On the other hand, in this embodiment, as shown in FIG. 10A, the second layer 43 is etched so that the side surfaces of the first layer 42 are exposed in a tapered shape in the inner wirings 33c and 49c. As a result, the third layer 41, which is a low-resistance material, and the first layer 42, which is a corrosion-resistant material, are in direct contact. As a result, the wiring resistance of the wirings 33 and 49 can be reliably reduced, and display without unevenness can be performed. Further, as shown in FIG. 10B, contact holes 52 are provided in the IC connection terminals 47 and the conduction pads 48. As a result, the contact area between the first layer 42, which is a corrosion-resistant material, and the third layer 41, which is a low-resistance material, can be increased, and the wiring resistance can be further reduced.

(Modification)
In the above embodiment, the wiring side etched portions shown in FIG. 10A are provided at two locations, the bent portion 49b of the wiring shown in FIG. 5 and the vicinity of the sealing material 13 of the main line portion 49a. However, this side-surface etched portion can be provided in several places other than the above. Further, the side-surface etched portion can be provided over the entire wiring.

  In the above embodiment, TaW is used for the first layer 42 of the wirings 33 and 49. Alternatively, the first layer 42 may be made of another material having corrosion resistance, such as Ta or another Ta alloy.

  In the above embodiment, Cr is used for the third layer 41 of the inner wirings 33c and 49c. Alternatively, the third layer 41 may be made of another low resistance material such as Mo, Al, or Ti.

  In the above embodiment, the present invention is applied to the wirings 33 and 49 formed on the element substrate 12. However, when the wiring is formed on the color filter substrate side, the present invention can be applied to the wiring.

  In the above embodiment, the present invention is applied to a liquid crystal display device using a TFD element. However, the present invention can also be applied to an active matrix liquid crystal display device using a two-terminal switching element other than the TFD element. . The present invention can also be applied to an active matrix liquid crystal display device using a three-terminal switching element such as a TFT (Thin Film Transistor). The present invention can also be applied to a simple matrix liquid crystal display device that does not use a switching element.

  The present invention also provides an electro-optical device other than a liquid crystal display device, for example, an organic EL device, an inorganic EL device, a plasma display device (PDP), an electrophoretic display (EPD), a field emission display device ( It can also be applied to FED (Field Emission Display).

(Embodiment of manufacturing method of electro-optical device)
Hereinafter, an embodiment of a method for manufacturing an electro-optical device according to the present invention will be described by taking as an example the case of manufacturing the liquid crystal display device 1 shown in FIG. FIG. 11 shows an example of a manufacturing method of the liquid crystal display device as a process diagram. In FIG. 11, steps P1 to P5 are steps for forming the element substrate 12 of FIG. Steps P11 to P18 are steps for forming the color filter substrate 11 of FIG. Steps P21 to P28 are steps for combining the substrates to complete the liquid crystal display device.

  In the manufacturing method of the present embodiment, the element substrate 12 and the color filter substrate 11 shown in FIG. 1 are not formed one by one, but the element substrate 12 has an area large enough to form a plurality of element substrates 12. A plurality of element substrates 12 are formed at the same time using an element-side mother base material having Regarding the color filter substrate 11, the plurality of color filter substrates 11 are simultaneously formed using a color filter-side mother base material having an area large enough to form the plurality of color filter substrates 11. The element side mother base and the color filter side mother base are formed of, for example, translucent glass, translucent plastic, or the like.

  First, in step P1 of FIG. 11, the TFD element 31 of FIG. 3, the wiring 33 and wiring 49 of FIG. 5, and the electrode 23b are simultaneously formed on the surface of the element-side mother base material. Next, in the process P2, the photo spacer 15 of FIG. 2 is formed by photolithography. The photo spacer 15 is desirably formed in a region other than the display dot region D of FIG. Further, in step P3, the alignment film 24b is formed by coating, printing, or the like, and in step P4, the alignment film 26b is subjected to an alignment process, for example, a rubbing process. Next, in step P5, for example, the sealing material 13 of FIG. 1 is formed by printing or the like using an epoxy resin as a material. As described above, the plurality of element substrates 12 are formed on the element-side mother substrate to form the element-side mother substrate.

  Next, in step P11 of FIG. 11, the first layer 17a of the resin layer 17 of FIG. 2 is formed on the surface of the color filter-side mother substrate by, for example, a photolithography process using a photosensitive resist material as a material. During this treatment, an uneven pattern formed by a large number of randomly distributed unevenness is formed on the surface of the first layer 17a.

  Thereafter, in FIG. 2, the second layer 17 b of the same material is thinly applied on the first layer 17 a to form the resin layer 17. The reason why the second layer 17b is laminated is to smooth the surface of the concave portion or the convex portion. Next, in step P12 of FIG. 11, the reflective film 18 of FIG. 2 is formed by photolithography and etching using, for example, Al or an Al alloy as a material. At this time, the light reflecting portion R and the light transmitting portion T are formed by forming the opening 46 for each display dot region D. Since the concave / convex pattern is formed on the surface of the resin layer 17, when the light hits the reflective film 18 laminated thereon and is reflected, the reflected light becomes scattered light.

  Next, in step P13, the light shielding member 21 in FIG. 2 is formed into a predetermined pattern (for example, a lattice pattern that fills around the plurality of display dot regions D) by photolithography and etching using, for example, Cr as a material. To form. Next, in the process P14, the coloring element 19 of FIG. 2 is formed. The coloring elements 19 are formed in order for each of R, G, and B colors. For example, a coloring material formed by dispersing pigments and dyes of respective colors in a photosensitive resin is formed in a predetermined arrangement by photolithography. Next, in process P15, the overcoat layer 22 of FIG. 2 is formed by photolithography using a photosensitive resin such as an acrylic resin or a polyimide resin as a material.

  Next, in step P16 in FIG. 11, the linear electrode 23a in FIG. 2 is formed by photolithography and etching using ITO as a material, and in step P17, the alignment film 24a in FIG. 2 is formed, and in step P18. A rubbing process is performed as an alignment process. As described above, the plurality of color filter substrates 11 are formed on the color filter side mother base material to form the color filter side mother substrate.

  Thereafter, in step P21 of FIG. 11, the element side mother substrate and the color filter side mother substrate are bonded together. As a result, a large-area panel structure having a structure in which the element-side mother substrate and the color filter-side mother substrate are bonded to each other with the sealant 13 in FIG.

  Next, the sealing material 13 included in the large-area panel structure formed as described above is cured in step P22 to bond both mother substrates. Next, in step P23, the panel structure is subjected to primary cutting, that is, primary break, and a medium-area panel structure including a plurality of liquid crystal panels 2 in FIG. A plurality of panel structures are formed. An opening is formed in advance in the sealing material 13 in advance, and when the strip-shaped panel structure is formed by the primary break, the opening of the sealing material 13 is exposed to the outside.

  Next, in step P24 of FIG. 11, liquid crystal is injected into each liquid crystal panel portion through the opening of the sealing material 13, and after the injection is completed, the opening is sealed with resin. Next, in step P25, a second cutting, that is, a secondary break is performed, and the individual liquid crystal panels 2 shown in FIG. 1 are cut out from the strip-shaped panel structure.

  Next, in step P26 of FIG. 11, the driving IC 3 of FIG. 1 is mounted. Next, in process P27, the polarizing plates 27a and 27b are attached to the liquid crystal panel 2 of FIG. 1 by sticking. Furthermore, in process P28, the illuminating device 4 of FIG. 1 is attached. Thereby, the liquid crystal display device 1 is completed.

  FIG. 12 shows an embodiment of the process P1 of forming the TFD element, electrode and wiring in FIG. This step is a step for manufacturing the TFD element 31 shown in FIG. 3, the wiring 33 and the wiring 49, and the electrode 23b shown in FIG. That is, in the present embodiment, the TFD element 31, the wiring 33, and the wiring 49 are performed in the same formation process.

  The TFD element, wiring and electrode forming process P1 is roughly divided into a base layer forming process Q1, a first metal forming process Q2, an insulating film forming process Q3, a so-called element part separating process Q4, and a second metal. And the like, and the formation step Q6 of the electrode and the like.

  The underlayer forming step Q1 is a step for forming an underlayer between the TFD element 31 and the base material 16b in FIG. 3, but the underlayer is not shown in FIG. Further, in the first metal forming step Q2, the first metal 36 of the TFD element 31 of FIG. 3 is formed, and the first layer 42 of the line wiring 33 and the wiring 49 (that is, a layer of corrosion resistant material) is formed. To do. In the formation process Q3 of the insulating film or the like, the insulating film 37 of the TFD element 31 is formed, and the second layer 43 (that is, the layer of insulating material) of the line wiring 33 and the wiring 49 is formed.

  Further, in the element part separation step Q4, the laminated structure of the first metal 36 and the insulating film 37 of the TFD element 31 is separated into an island shape having the size of one TFD element 31. At the same time, part or all of the side surface of the inner wiring 33c of the line wiring 33 and part or all of the side surface of the inner wiring 49c of the wiring 49 are removed to an appropriate depth by etching. At the same time, contact holes 52 are formed in the internal regions of the line wiring 33 and the wiring 49.

  In the second metal forming step Q5, the second metal 38 of the TFD element 31 is formed, and the third layer 41 (that is, a layer of low resistance material) of the line wiring 33 and the wiring 49 is formed. In the electrode forming step Q6, the dot electrode 23b is formed, and the ITO film of the terminal portion of the line wiring 33, the ITO film of the terminal portion of the wiring 49, and the ITO film of the conductive pad portion of the wiring 49 are formed. .

Hereinafter, the process of forming the TFD element, the wiring, and the electrode will be described more specifically. First, in step P31, Ta ₂ O ₅ (tantalum pentoxide) is formed by sputtering to form an underlayer. Next, in Step P32, TaW is deposited with a uniform thickness by sputtering. Next, in process P33, a photoetching process, that is, a photolithography process and an etching process are performed. Thereby, the non-pad-like first metal 36 is formed. At this time, the first layer 42 (see FIG. 9) of the wirings 33 and 49 of FIG. 5 is formed at the same time. Note that the resist stripping is performed using an H ₂ SO ₄ solution.

  The non-pad-shaped first metal 36 is a continuous first metal 36 that is not island-shaped. The first metal 36 shown in FIG. 3 is independent in an island shape, one for each dot electrode 23b. In this specification, such an island-independent state is referred to as a pad shape. In the first metal forming step Q2 of FIG. 12, the pad-shaped first metal 36 is not formed suddenly, but the first metal 36 in a state where a plurality of island-shaped first metals 36 are continuous with each other, or the line A first metal 36 that is connected to the first layer 42 of the wiring 33 is formed. At this time, the first metal 36 extending linearly continuously and the first metal 36 connected to the first layer 42 are the non-pad-shaped first metal 36.

Next, in step P34, an anodizing process is performed to form the insulating film 37 in FIG. At the same time, the second layer 43 (see FIG. 9) of the wirings 33 and 49 is formed. Next, in step P35, unnecessary portions of the insulating film 37 and the first metal 36 are removed by etching by dry etching, and the resist film is peeled off with an H ₂ SO ₄ solution, whereby the pad-shaped first metal 36 is removed. Then, an insulating film 37 is formed. At the same time, the side surface of the inner wiring 49c shown in FIGS. 8 and 7 is removed by dry etching. At the same time, contact holes 52 are formed in the conduction pads 48 in FIG. 8 and the IC connection terminals 47 in FIG. The side surfaces of the inner wirings 33c and 49c and the inner peripheral surface of the contact hole 52 are tapered as shown in FIGS. 10 (a) and 10 (b). Thereby, the contact surface 51 with the 3rd layer 41 can be enlarged, and wiring resistance can be made low reliably.

  Next, in step P36 of FIG. 12, a Cr film is formed with a uniform thickness by sputtering. Next, in step P37, the Cr film is patterned by photoetching to form the second metal 38 shown in FIG. At the same time, the third layer 41 of the wirings 33 and 49 is formed by photoetching. In step P36, the third layer 41 is formed over the entire wirings 33 and 49. That is, a film is also formed on the outer wirings 33 d and 49 d located outside the sealing material 13. However, when the third layer 41 is patterned in the photoetching process of Step P37, the third layer 41 outside the sealing material 13 is removed. As a result, the outer wirings 33 d and 49 d become a corrosion-resistant wiring having a two-layer structure including the first layer 42 and the second layer 43. As a result, even if a foreign object is placed on the outer wirings 33d and 49d, it is safe without causing a short circuit between the plurality of wirings provided on the substrate.

  Next, in process P38, ITO, which is the material of the dot electrode 23b, is formed with a uniform thickness by sputtering. Next, in step P39, the electrode 23b is formed in a predetermined dot shape by performing a photoetching process on the ITO. At this time, an ITO film is also simultaneously formed on the conduction pad 48 and the IC connection terminal 47.

  As described above, in the method for manufacturing the liquid crystal display device according to the present embodiment, the second layer 43 of the wirings 33 and 49 is removed by etching to expose the first layer 42, and then the third layer is formed thereon. Layer 41 was formed. As a result, the first layer 42 and the third layer 41 can be brought into direct contact with each other in the etched portion. As a result, it is possible to reduce the wiring resistance and prevent the display displayed in the display area V from being uneven. Further, since the etched portion has a tapered shape, the contact surface 51 between the first layer 42 and the third layer 41 can be increased, and thereby the wiring resistance can be further reduced.

  In the present embodiment, in the series of processes from step P32 to step P39 in FIG. 12, the line wiring 33 and the wiring 39 are formed simultaneously with the formation of the TFD element 31. As a result, it is possible to manufacture a wiring having both corrosion resistance and low resistance without increasing the number of processes.

(Modification)
In the above embodiment, the wiring side etched portions shown in FIG. 10A are provided at two locations, the bent portion 49b of the wiring shown in FIG. 5 and the vicinity of the sealing material 13 of the main line portion 49a. However, this side-surface etched portion can be provided in several places other than the above. Further, the side-surface etched portion can be provided over the entire wiring.

  In the above embodiment, TaW is used for the first layer 42 of the wirings 33 and 49. Alternatively, the first layer 42 may be made of another material having corrosion resistance, such as Ta or another Ta alloy.

  In the above embodiment, Cr is used for the third layer 41 of the inner wirings 33c and 49c. Alternatively, the third layer 41 may be made of another low resistance material such as Mo, Al, or Ti.

(Embodiment of electronic device)
Next, an embodiment of an electronic device according to the present invention will be described with reference to the drawings. FIG. 13 shows a block diagram of an embodiment of an electronic device. The electronic apparatus shown here includes the liquid crystal display device 1 and a control circuit 80 that controls the liquid crystal display device 1. The liquid crystal display device 1 includes a liquid crystal panel 81 and a drive circuit 82 composed of a semiconductor IC or the like. The control circuit 80 includes a display information output source 83, a display information processing circuit 84, a power supply circuit 86, and a timing generator 87.

  The display information output source 83 includes a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), a storage unit such as a magnetic recording disk or an optical recording disk, and a tuning circuit that tunes and outputs a digital image signal. Have The display information output source 83 supplies display information to the display information processing circuit 84 in the form of an image signal of a predetermined format based on various clock signals generated by the timing generator 87.

  The display information processing circuit 84 includes various known circuits such as a serial-parallel conversion circuit, an amplification / inversion circuit, a rotation circuit, a gamma correction circuit, and a clamp circuit, and executes processing of input display information to obtain image information thereof. Are supplied to the drive circuit 82 together with the clock signal CLK. The drive circuit 82 includes a scanning line drive circuit, a data line drive circuit, and an inspection circuit. The power supply circuit 86 supplies a predetermined voltage to each of the above components.

  FIG. 14 shows an embodiment when the present invention is applied to a mobile phone which is an example of an electronic apparatus. A cellular phone 70 shown here has a main body 71 and a display body 72 provided on the main body 71 so as to be opened and closed. A display device 73 configured by an electro-optical device such as a liquid crystal display device is disposed inside the display body portion 72, and various displays related to telephone communication can be visually recognized on the display body portion 72 on the display screen 74. Operation buttons 76 are arranged on the main body 71.

  An antenna 77 is attached from one end portion of the display body portion 72 so as to be extendable. A speaker (not shown) is disposed inside the receiver 78 provided at the upper part of the display body 72. In addition, a microphone (not shown) is built in the transmitter 79 provided at the lower end of the main body 71. A control unit for controlling the operation of the display device 73 is stored in the main body 71 or the display body 72 as a part of the control unit that controls the entire mobile phone or separately from the control unit. The

  FIG. 15 shows an embodiment in which the present invention is applied to a portable information device which is another example of an electronic device. A portable information device 90 shown here is an information device provided with a touch panel, and is equipped with a liquid crystal display device 91 as an electro-optical device. The information device 90 has a display area V constituted by the display surface of the liquid crystal display device 91 and a first input area W1 positioned below the display area V. An input sheet 92 is disposed in the first input area W1.

  The liquid crystal display device 91 has a structure in which a rectangular or square liquid crystal panel and a rectangular or square touch panel overlap in a planar manner. The touch panel functions as an input panel. The touch panel is larger than the liquid crystal panel, and has a shape protruding from one end of the liquid crystal panel.

  A touch panel is disposed in the display area V and the first input area W1, and the area corresponding to the display area V also functions as a second input area W2 in which an input operation can be performed in the same manner as the first input area W1. The touch panel has a second surface located on the liquid crystal panel side and a first surface facing the second surface, and an input sheet 92 is pasted at a position corresponding to the first input area W1 on the first surface. .

  The input sheet 92 is printed with a frame for identifying the icon 93 and the handwritten character recognition area W3. In the first input area W1, by applying a load to the first surface of the touch panel with an input device such as a finger or a pen through the input sheet 92, selection of the icon 93, character input in the character recognition area W3, etc. Data input can be performed.

  On the other hand, in the second input area W2, an image of the liquid crystal panel can be observed. For example, an input mode screen is displayed on the liquid crystal panel, and a load is applied to the first surface of the touch panel with a finger or a pen. An appropriate position in the input mode screen can be designated, thereby enabling data input or the like.

(Modification)
The electronic device according to the present invention includes a personal computer, a liquid crystal television, a digital still camera, a wristwatch, a viewfinder type or a monitor direct view type video tape recorder, car navigation, as well as the above-described cellular phone and portable information device. A device, a pager, an electronic notebook, a calculator, a word processor, a workstation, a video phone, a POS terminal, and other various devices can be considered.

In the liquid crystal display device 1 of FIG. 1, as the third layer 41 (see FIG. 9B) of the inner wirings 33c and 49c of FIG.
(1) using Cr, and
(2) Two types of those using ITO were manufactured. And about these liquid crystal display devices, the characteristic regarding the electrical connection of the 1st layer 42 and the 3rd layer 41 was investigated. Note that Ta was used for the first layer 42.

  As a result, the results of FIGS. 16 and 17 were obtained. FIG. 16 shows the result of the above condition (1) using Cr as the third layer 41, where (a) shows the relationship between the voltage applied to the wiring and the current, and (b) shows the application to the wiring. The relationship between the voltage and the resistance value of the entire wiring is shown. In addition, the graph of FIG.16 (b) was created based on the measured value of Fig.16 (a). FIG. 17 shows the result of the above condition (2) using ITO as the third layer 41. FIG. 17A shows the relationship between the voltage applied to the wiring and the current, and FIG. Represents the relationship between the applied voltage and the resistance value of the entire wiring. In addition, the graph of FIG.17 (b) was created based on the measured value of Fig.17 (a).

The following results were found from the above experimental results.
(1) Between Cr and Ta, the current value and the resistance value are constant regardless of the voltage value, and a stable electrical connection can be obtained.
(2) Between ITO and Ta, both current value and voltage value showed unstable characteristics. For example, as shown in FIG. 17B, in the first experiment, as the voltage was increased, the resistance value decreased and showed a constant value from the middle. In the second and third times, a substantially constant resistance value was shown regardless of the voltage value.
(3) Since the ITO film is formed by sputtering, an oxide film is formed on the surface. As a result, the electrical connection becomes unstable.
(4) Judging from the results of (1) to (3) above, it is preferable that Cr is used for the low resistance material used in the liquid crystal display device in this embodiment rather than ITO.

  The electro-optical device according to the present invention is suitably used as a display device capable of performing display without display unevenness when performing various displays on a mobile phone, a portable information terminal, and other electronic devices. In addition, the method for manufacturing an electro-optical device according to the present invention is preferably used when manufacturing an electro-optical device having a wiring structure having both corrosion resistance and low resistance. The electronic device according to the present invention is used as a consumer device such as a mobile phone or a portable information terminal, a measuring instrument or other industrial device.

1 is a cross-sectional view showing a liquid crystal display device which is an embodiment of an electro-optical device according to the invention. It is sectional drawing which expands and shows the principal part of FIG. It is a perspective view which shows an example of the switching element used with the apparatus of FIG. It is a top view of the liquid crystal display device according to the arrow A of FIG. It is a top view which shows an element substrate according to the arrow A of FIG. It is a top view which shows a color filter board | substrate according to the arrow A of FIG. It is a top view which expands and shows the part shown by the arrow B of FIG. It is a top view which expands and shows the part shown by the arrow C of FIG. (A) is sectional drawing according to the EE line | wire of FIG. 8, (b) is sectional drawing according to the FF line | wire of FIG. (A) is a cross-sectional view according to the HH line of FIG. 8 and the II line of FIG. 7, and (b) is a cross-section according to the LL line of FIG. 8 and the KK line of FIG. FIG. FIG. 6 is a process diagram illustrating an embodiment of a method for manufacturing an electro-optical device according to the invention. It is process drawing which shows an example of the content of the main processes of FIG. It is a block diagram which shows one Embodiment of the electronic device which concerns on this invention. It is a perspective view which shows other embodiment of the electronic device which concerns on this invention. It is a perspective view which shows other embodiment of the electronic device which concerns on this invention. 6 is a graph showing experimental results regarding wiring used in the electro-optical device according to the present invention, where (a) shows the characteristics of the applied voltage and current, and (b) shows the characteristics of the applied voltage and wiring resistance. 6 is a graph showing another experimental result regarding wiring used in the electro-optical device according to the present invention, where (a) shows characteristics of applied voltage and current, and (b) shows characteristics of applied voltage and wiring resistance. Yes.

Explanation of symbols

1. 1. liquid crystal display device (electro-optical device), Liquid crystal panels, 3a, 3b. Driving IC, 4. 5. lighting device; 6. light source; 10. light guide; Color filter substrate,
12 Element substrate, 13. Sealing material, 14. Liquid crystal, 15. Photo spacer,
16a, 16b. Base material 17a, 17b. Resin layer, 18. Reflective layer 19. Coloring elements,
21. Light shielding member 22. Overcoat layer, 23a. Linear electrodes,
23b. Dot electrodes, 24a, 24b. Alignment films, 26a, 26b. Retardation plate,
27a, 27b. Polarizing plate, 29. Overhang part 31. TFD element,
33. Line wiring, 33c. Inside wiring of line wiring,
33d. 36. outside wiring of line wiring; First metal, 37. Insulation film,
38. Second metal, 49, wiring, 49c. Inner wiring, 49d. Outer wiring,
41. Third layer, 42. First layer, 43. Second layer, 44. External connection terminal,
45. ITO film 47. IC connection terminal, 48. Pad for conduction,
49a, main line part, 49b. 51. a bent part; Contact surface, 52. Contact hole,
53. Anisotropic conductive film, 54. Conductive material, 70. Mobile phones (electronic devices),
73. Liquid crystal display device, 90. Portable information device (electronic device), 91. Liquid crystal display,
D. Display dot area, L0. External light, L1. Transmitted light; Reflector, T. Transmission part,
V. Indicated Area

Claims (13)

In an electro-optical device having an electro-optical material provided inside a sealing material, an inner wiring provided inside the sealing material, and an outer wiring provided outside the sealing material,
The inner wiring has a laminated structure formed by forming an insulating material on a corrosion-resistant material and forming a low-resistance material thereon.
The outer wiring has a corrosion resistant material,
The electro-optical device according to claim 1, wherein a part or all of the side surfaces of the inner wiring have a portion in which the corrosion-resistant material and the low-resistance material are in direct contact due to the absence of the insulating material.   2. The electro-optical device according to claim 1, wherein a portion where the corrosion-resistant material and the low-resistance material are in direct contact is a tapered surface.   3. The electro-optical device according to claim 1, wherein the corrosion-resistant material is Ta (tantalum) or Ta (tantalum) alloy.   4. The electro-optical device according to claim 1, wherein the low-resistance material is Cr (chromium), Mo (molybdenum), Al (aluminum), Ti (titanium), or one of them. An electro-optical device, wherein the electro-optical device is one selected from alloys having a main component.   5. The electro-optical device according to claim 1, wherein the inner wiring and the outer wiring form a continuous wiring extending across the sealing material. 6.   6. The electro-optical device according to claim 1, further comprising an electrode for applying a voltage to the electro-optical material, wherein the inner wiring is connected to the electrode. Electro-optic device.   7. The electro-optical device according to claim 1, wherein the layer made of the corrosion resistant material and the insulating material forming the inner wiring has a contact hole, and the low resistance material is An electro-optical device that enters an inside of a contact hole and makes direct contact with the corrosion-resistant material.   8. The electro-optical device according to claim 7, wherein the inner wiring has a conductive pad portion that contacts conductive particles inside the sealing material, and the contact hole is provided in the conductive pad portion. . A pair of substrates bonded together by a sealing material;
Liquid crystal sealed in a region surrounded by the sealing material and the pair of substrates;
Electrodes provided on the respective surfaces of the pair of substrates and inside the sealing material;
In an electro-optical device having a wiring extending from the electrode and extending to the outside of the sealing material,
The inner wiring located inside the sealing material among the wiring has a laminated structure in which an insulating material is formed on a corrosion-resistant material and a low-resistance material is formed thereon.
Outer wiring located outside the sealing material among the wiring has a corrosion-resistant material,
The electro-optical device according to claim 1, wherein a part or all of the side surfaces of the inner wiring have a portion in which the corrosion-resistant material and the low-resistance material are in direct contact due to the absence of the insulating material. Forming a sealing material on the substrate;
Providing an electro-optic material inside the sealing material;
In the method of manufacturing an electro-optical device, including a step of forming wiring on both the inside and the outside of the sealing material,
The step of forming the wiring includes
Forming a first layer of a corrosion-resistant material inside the sealing material;
Forming a second layer of an insulating material on the first layer;
An etching step of removing a part or all of the side surface of the wiring formed by laminating the first layer and the second layer by etching;
And a step of forming a third layer on the second layer with a low-resistance material.   11. The method of manufacturing an electro-optical device according to claim 10, wherein a side surface of the first layer is formed into a tapered surface in the etching step.   12. The method of manufacturing an electro-optical device according to claim 10, wherein in the step of forming the third layer, a third layer is formed inside and outside the sealing material, and thereafter, outside the sealing material. A method of manufacturing an electro-optical device, wherein the third layer is removed. An electronic apparatus comprising the electro-optical device according to claim 1.

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