JP2008009920A - Input device and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an input device capable of preventing occurrence of electrical failure, and a manufacturing method therefor. <P>SOLUTION: The input device, for inputting according to a position in an effective area, is equipped with a transparent substrate 132, a second transparent conductive film 46 provided on the transparent substrate 132, a second electrode 32 formed with the second transparent conductive film 46, and a second interconnection line 36 provided outside the effective area and connected to a second electrode 32. The second interconnection line 36 has the second transparent conductive film 46 and a metal film 47 formed on the second transparent conductive film 46. One end of a pattern of the metal film 47 in a width direction of the second interconnection line 36 is disposed inside the second transparent conductive film 46. Another end of the pattern of the metal film 47 in a width direction of the second interconnection line 36 is disposed on the second transparent conductive film 46. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an input device and a manufacturing method thereof, and more particularly to an input device having an electrode formed of a transparent conductive film and a manufacturing method thereof.

  2. Description of the Related Art In recent years, a transparent touch panel that is arranged on a display surface of a display device and is directly pressed by a user's finger to perform an input operation such as desired function selection has been widely used. In particular, when portability and operability are regarded as important, such as mobile terminals and bank terminals, touch panels are widely used instead of keyboards. Since the input method using the touch panel can be directly input by the user according to the display screen, it does not require knowledge or skill of a computer, and the operability is very good.

  2. Description of the Related Art Conventionally, a capacitive touch panel has been developed as one that outputs a current signal corresponding to a position when an input position on the touch panel is touched with a finger or the like (see, for example, Patent Document 1). This capacitive touch panel includes, for example, an electrode substrate in which electrodes made of a transparent conductive film for detecting a contact position are provided on both outer surfaces of two transparent substrates made of glass or the like, and a contact surface side of the electrode substrate It is comprised from the cover bonded together by the transparent adhesive material. The surface of the cover becomes an operation surface with which a finger contacts during operation. The electrodes provided on both outer surfaces of the electrode substrate are formed so as to cross each other.

JP-A-5-160526

  A connection wiring for connecting the electrode and the external wiring is formed on the electrode substrate. The connection wiring is formed in a region that is not visible from the outside. For this reason, a metal film can be used for the connection wiring. In order to reduce the resistance, a laminated structure of a metal film and a transparent conductive film is used for the connection wiring. The metal film and the transparent conductive film are patterned by, for example, a photolithography method.

  Here, when a metal film is formed on the transparent conductive film, the metal film protrudes from the transparent conductive film due to a positional shift during patterning. Alternatively, in the pattern design, a metal film may be formed so as to cover the transparent conductive film, or a metal film may be formed so as to connect between the patterns of the transparent conductive film. Thus, when the metal film is formed so as to protrude from the transparent conductive film, a step is formed below the metal film at the pattern end of the transparent conductive film. That is, the metal film is formed so as to straddle the step at the pattern end of the transparent conductive film. As a result, there is a problem that an electrical failure occurs in the connection wiring. For example, when the metal film is patterned after patterning the transparent conductive film, wet etching may be used for etching the metal film. In this case, if the coverage of the metal film straddling the step portion at the pattern end of the transparent conductive film is poor, the etching solution may penetrate into the gap generated in the step portion and the metal film may be peeled off. When such film peeling occurs, adjacent metal wires are short-circuited by the peeled metal film. Alternatively, the metal film wiring may be disconnected. Furthermore, when partial film peeling occurs, disconnection or the like may be delayed due to deterioration due to use after commercialization. Therefore, the conventional input device has a problem that an electrical failure occurs when the connection wiring has a laminated structure in order to reduce resistance.

  The present invention has been made in view of such problems, and an input device capable of suppressing the occurrence of electrical failure by eliminating the stepped portion between the metal film and the transparent conductive film, and a method for manufacturing the same. The purpose is to provide.

  An input device according to a first aspect of the present invention is an input device that performs input in accordance with a position in an effective area, and includes a transparent substrate, a transparent conductive film provided on the transparent substrate, and the effective area. A transparent electrode formed by the transparent conductive film provided inside, and a connection wiring provided outside the effective area and connected to the transparent electrode, wherein the connection wiring is the transparent conductive film, and A metal film formed on the transparent conductive film, wherein one end of the pattern of the metal film in the width direction of the connection wiring is on the transparent conductive film, and the end of the pattern of the transparent conductive film The other end of the pattern of the metal film in the width direction of the connection wiring is disposed on the transparent conductive film. Thereby, generation | occurrence | production of an electrical failure can be suppressed.

  In the input device according to the second aspect of the present invention, in the input device, the pattern width of the transparent conductive film in the width direction of the connection wiring is 10 μm or more wider than the pattern width of the metal film. It is a feature. Thereby, generation | occurrence | production of an electrical failure can be suppressed reliably.

  A method for manufacturing an input device according to a third aspect of the present invention includes: a transparent electrode provided in an effective area; and a connection wiring provided outside the effective area and connected to the transparent electrode; A method of manufacturing an input device that performs input according to a position in the effective area, the step of forming a transparent conductive film to be the transparent electrode and the connection wiring on a transparent substrate, and the transparent conductive film A step of forming a pattern of the metal film, and a step of forming a pattern of the transparent conductive film after forming the pattern of the metal film, and in the step of forming the pattern of the transparent conductive film, One end of the pattern of the metal film in the width direction of the connection wiring is disposed on the transparent conductive film and inside the end of the pattern of the transparent conductive film, and the metal film in the width direction of the connection wiring The pa The other end of the over emissions, as disposed on the transparent conductive film, thereby forming a pattern of the transparent conductive film. Thereby, it can prevent that a level | step-difference part arises and generation | occurrence | production of an electrical failure can be suppressed.

  In the method of manufacturing the input device according to the fourth aspect of the present invention, in the step of forming the metal film pattern, after forming the metal film, the first resist pattern is formed on the metal film, In the step of forming the pattern of the metal film by etching the metal film through the first resist pattern and forming the pattern of the transparent conductive film, the second resist pattern is changed to the metal film, and A pattern of the transparent conductive film is formed by forming the transparent conductive film on the transparent conductive film and etching the transparent conductive film through the second resist pattern. Thereby, generation | occurrence | production of an electrical failure can be suppressed easily.

  ADVANTAGE OF THE INVENTION According to this invention, the input device which can suppress generation | occurrence | production of an electrical failure, and its manufacturing method can be provided.

  Hereinafter, embodiments to which the present invention can be applied will be described. The following description explains the embodiment of the present invention, and the present invention is not limited to the following embodiment.

  An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view illustrating an example of a configuration of a display device 100 on which an input device 10 according to an embodiment is mounted. The display device 100 according to the present embodiment includes a display element 20 and an input device 10 disposed on the viewing side of the display element 20. The input device 10 is, for example, a touch panel, and includes a cover 11, an adhesive layer 12, an electrode substrate 13 made of two transparent substrates, and an adhesive layer 14 in order from the viewing side. In the present embodiment, the display element 20 is a liquid crystal display element, and includes a polarizing plate 26, a counter substrate 24, a TFT array substrate 23, a polarizing plate 25, and a backlight unit 22 in order from the viewing side.

  First, the configuration of the display element 20 will be described. Here, an active matrix liquid crystal display element will be described as an example of a display element. Of course, the display element 20 is not limited to an active matrix liquid crystal display element, and may be a passive matrix liquid crystal display element. Furthermore, the display element 20 is not limited to a liquid crystal display element, and may be another display element such as an organic EL display element. The display element 20 performs image display based on the input display signal. The display element 20 includes a liquid crystal display panel 21 and a backlight unit 22. The liquid crystal display panel 21 has a configuration in which liquid crystal is sealed between the counter substrate 24 and the TFT array substrate 23. The counter substrate 24 and the TFT array substrate 23 are made of a transparent glass substrate, for example.

  A plurality of scanning lines are formed on the TFT array substrate 23 at regular intervals. A plurality of signal lines are formed at regular intervals on the scanning lines. The scanning line and the signal line are arranged so as to intersect with each other via an insulating film. A thin film transistor (TFT), which is a switching element, is disposed in the vicinity of the intersection of the scanning line and the signal line. A display signal is supplied from the signal line to the pixel electrode via the TFT. The pixel electrode is formed of a transparent conductive film such as ITO (Indium Tin Oxide), for example. The display area of the liquid crystal display panel 21 is composed of a plurality of pixels. The display area is usually formed in a rectangular shape. Further, the liquid crystal display panel 21 is provided with a frame area provided so as to surround the display area.

  A driving circuit (not shown) is connected to the liquid crystal display panel 21. The drive circuit outputs various control signals, scanning voltages, display voltages, and the like necessary for image display based on display signals input from the outside. The drive circuit may be mounted on the end of the TFT array substrate 23 by COG (Chip On Glass). The counter substrate 24 is, for example, a color filter substrate. On the counter substrate 24, for example, a black matrix (BM) and colored layers of R, G, and B are formed. The colored layer is formed between the BMs and corresponds to the pixels. A counter electrode made of a transparent conductive film such as ITO is formed on the colored layer and BM. The alignment state of the liquid crystal changes depending on the voltage between the pixel electrode and the counter electrode. Thereby, the amount of light transmitted through the liquid crystal display panel 21 is adjusted, and display can be performed.

  Such a TFT array substrate 23 and the counter substrate 24 are bonded to each other through a sealing material. Polarizing plates 25 and 26 are bonded to the outer surfaces of the TFT array substrate 23 and the counter substrate 24, respectively. Thereby, the liquid crystal display panel 21 is formed. Specifically, a polarizing plate 25 is provided on the surface of the TFT array substrate 23 on the non-viewing side. A polarizing plate 26 is bonded to the surface on the viewing side of the counter substrate 24. The polarizing plate 26 and the polarizing plate 25 each have an absorption axis in a predetermined direction. Therefore, the light passing through the polarizing plate 26 or the polarizing plate 25 becomes linearly polarized light. Thus, the display element 20 includes the liquid crystal display panel 21 having a general configuration.

  A backlight unit 22 is provided on the back side of the liquid crystal display panel 21. The backlight unit 22 irradiates the liquid crystal display panel 21 with planar light from the non-viewing side of the liquid crystal display panel 21. As the backlight unit 22, for example, a unit having a general configuration including a light source, a light guide plate, a prism sheet, and the like is used. The display element 20 displays buttons indicating processing details, icons, and the like.

  Next, the configuration of the input device 10 disposed on the viewing side of the display element 20 will be described. The input device 10 is, for example, a capacitive touch panel. On the viewing side of the display element 20, an electrode substrate 13 including two transparent substrates 131 and 132 is disposed. Transparent electrodes are formed on both outer surfaces of the transparent substrates 131 and 132, respectively. The configuration of the electrode substrate 13 will be described later. An adhesive layer 14 is provided between the electrode substrate 13 and the display element 20. The adhesive layer 14 is, for example, a double-sided adhesive tape or an adhesive, and bonds the display element 20 and the electrode substrate 13 together. The adhesive layer 14 is formed of, for example, a transparent resin material having a thickness of 125 μm.

  A cover 11 for protecting the electrode substrate 13 and the like is disposed on the viewing side of the electrode substrate 13. The cover 11 is made of, for example, a plastic plate having a thickness of 0.8 mm. An adhesive layer 12 is provided between the cover 11 and the electrode substrate 13. Note that the surface of the cover 11 serves as an operation surface with which a position indicator such as a finger contacts during operation.

  The adhesive layer 12 is, for example, a double-sided adhesive tape or an adhesive, and bonds the cover 11 and the electrode substrate 13 together. The adhesive layer 12 is formed of, for example, a transparent resin material having a thickness of 175 μm. The adhesive layer 12 and the adhesive layer 14 are disposed over the entire display area.

  A first FPC (Flexible Printed Circuit) 15 and a second FPC 16 are connected to one end of the electrode substrate 13. The first FPC 15 is attached to the surface on the viewing side of the transparent substrate 131, and the second FPC 16 is attached to the surface on the non-viewing side of the transparent substrate 132. The first FPC 15 and the second FPC 16 are connected to a detection circuit, a drive circuit, and the like. Signals are input / output to / from the electrode substrate 13 by the first FPC 15 and the second FPC 16.

  Next, the configuration of the electrode substrate 13 will be described with reference to FIGS. FIG. 2 is a diagram showing the configuration of the electrode substrate 13. FIG. 3 is a plan view showing a pattern of electrodes formed on one substrate of the electrode substrate 13, that is, the transparent substrate 131 on the viewing side. FIG. 4 is a plan view showing an electrode pattern formed on the other substrate of the electrode substrate 13, that is, the transparent substrate 132 on the counter-viewing side.

  As shown in FIGS. 2 to 4, the electrode substrate 13 includes transparent substrates 131 and 132 made of glass or the like. As shown in FIG. 3, a plurality of first electrodes 31 extending in parallel to each other in the vertical direction are formed on the surface on the viewing side of the transparent substrate 131. In addition, as shown in FIG. 4, a plurality of second electrodes 32 extending in parallel with each other in the horizontal direction are formed on the surface of the transparent substrate 132 on the non-viewing side. Therefore, as shown in FIG. 2, the first electrode 31 and the second electrode 32 are formed on the electrode substrate 13 so as to intersect each other. That is, the first electrode 31 and the second electrode 32 are arranged so as to be orthogonal to each other with the transparent substrates 131 and 132 interposed therebetween. Note that the transparent substrate 131 and the transparent substrate 132 are bonded to each other through a sealing material (not shown).

  A region where the first electrode 31 and the second electrode 32 are formed is an effective area 33. The effective area 33 corresponds to the display area of the display element 20. Therefore, the effective area 33 is formed in the same rectangular shape as the display area of the display element 20. A frame-shaped area outside the effective area 33 is a non-effective area 34.

  Here, the surface on which the first electrode 31 of the electrode substrate 13 is formed is the surface on the viewing side, that is, the surface on the adhesive layer 12 side, and the surface on which the second electrode 32 is formed is the surface on the anti-viewing side, That is, the surface on the adhesive layer 14 side.

  The first electrode 31 and the second electrode 32 formed in the effective area 33 are made of, for example, ITO. Further, the conductive film is not limited to ITO, but may be other transparent conductive films such as IZO and ITZO. Therefore, the effective area 33 of the input device 10 is transparent, and the content displayed on the display element 20 can be confirmed via the input device 10 from the viewing side.

  As shown in FIG. 3, a plurality of first electrodes 31 are arranged at regular intervals on the surface of the electrode substrate 13 on the viewing side. A first connection wiring 35 connected to the first electrode 31 is formed in the ineffective area 34. The first connection wiring 35 is connected to the first electrode 31. In FIG. 3, six first connection wirings 35 are formed in order to be connected to the six first electrodes 31. In addition, the number of the 1st electrode 31 and the 1st connection wiring 35 is not restricted to this.

  The first connection wiring 35 is connected to the first electrode 31 at the lower end of the effective area 33. The first connection wiring 35 extends from the lower end of the effective area 33 to the lower end of the transparent substrate 131. For example, the first connection wiring 35 is formed of the same transparent conductive film as the first electrode 31. That is, the first connection wiring 35 extends from the first electrode 31. A first FPC 15 connected to the first connection wiring 35 is provided at the lower end of the transparent substrate 131. A first external terminal connected to the first FPC 15 is formed at the end of the first connection wiring 35.

  On the other hand, as shown in FIG. 4, a plurality of second electrodes 32 are arranged at regular intervals on the surface of the electrode substrate 13 on the non-viewing side. The non-effective area 34 is provided with a second connection wiring 36 connected to the second electrode 32. The second connection wiring 36 is connected to the second electrode 32. In FIG. 4, six second connection wirings 36 are formed to be connected to the six second electrodes 32. In addition, the number of the 2nd electrode 32 and the 2nd connection wiring 36 is not restricted to this.

  The second connection wiring 36 is connected to the second electrode 32 at the right end or the left end of the effective area 33. The second connection wiring 36 extends from the right end or the left end of the effective area 33 to the lower end of the transparent substrate 132. The second connection wiring 36 has a laminated structure of a transparent conductive film and a metal film. For example, the second connection wiring 36 can be formed by the same transparent conductive film as the second electrode 32 and a metal film formed thereon. Of course, the configuration of the second connection wiring 36 is not limited to this. A second FPC 16 connected to the second connection wiring 36 is provided at the lower end of the transparent substrate 132. A second external terminal connected to the second FPC 16 is formed at the end of the second connection wiring 36.

  The first FPC 15 and the second FPC 16 are attached to the transparent substrates 131 and 132 at the lower ends of the transparent substrates 131 and 132. That is, the first FPC 15 and the second FPC 16 are attached to the end portions on the same side of the transparent substrates 131 and 132. By setting it as such a structure, 1st FPC15 and 2nd FPC16 are arrange | positioned on the same side so that it may overlap. Therefore, a simple device configuration can be achieved.

  Next, the configuration of the second connection wiring 36 will be described with reference to FIG. FIG. 5A is a plan view showing configurations of the second connection wiring 36 and the second electrode 32. FIG. 5B is a cross-sectional view taken along the line AA of FIG. 5A, and shows a configuration when the second connection wiring 36 is cut along the width direction. FIG. 5C is a cross-sectional view showing a configuration of the second connection wiring 36 different from that in FIG. In FIG. 5, the second connection wiring 36 provided in the non-effective area 34 is schematically shown on the left side, and the configuration of the second electrode 32 provided in the effective area is schematically shown on the right side. In FIG. 5, the second connection wiring 36 and the second electrode 32 are illustrated with the same pattern width, but may be formed with different pattern widths. First, the configuration of the second connection wiring 36 will be described with reference to FIGS. 5A and 5B.

  The second connection wiring 36 has a laminated structure of a second transparent conductive film 46 and a metal film 47. For the metal film 47, for example, Al, Al alloy, Au, Au alloy, Ag, or Ag alloy can be used. Furthermore, you may laminate | stack said material and Mo, Mo alloy, Cr, Cr alloy, Ni, and Ni alloy. The metal film 47 is formed without protruding from the second transparent conductive film 46. Therefore, the metal film 47 is formed in an island shape on the second transparent conductive film 46. The second electrode 32 is composed of only a single layer of the second transparent conductive film 46.

  In the second connection wiring 36, the pattern width of the second transparent conductive film 46 is larger than the pattern width of the metal film 47. The metal film 47 is disposed only on the second transparent conductive film 46 without protruding from the pattern of the second transparent conductive film 46. That is, the pattern of the metal film 47 is included on the pattern of the second transparent conductive film 46. Accordingly, the pattern of the metal film 47 is disposed on the second transparent conductive film 46 in the width direction of the second connection wiring 36. The entire pattern end of the metal film 47 is disposed on the second transparent conductive film 46. As a result, the metal film 47 is disposed in a flat place without a step. Therefore, it is possible to suppress the occurrence of electrical failure due to disconnection or the like. Note that the width direction of the wiring is a wiring direction of the wiring, that is, a direction orthogonal to the longitudinal direction.

  Here, the difference in pattern width between the metal film 47 and the second transparent conductive film 46 in the width direction of the second connection wiring 36 is set in consideration of a positional shift due to an alignment error. For example, the pattern width of the second transparent conductive film 46 is 40 μm. A case where a positional deviation of 5 μm at the maximum occurs when patterning the second transparent conductive film 46 and the metal film 47 will be described. In this case, considering that a positional deviation of ± 5 μm occurs, the pattern width of the metal film 47 is made 10 μm smaller than that of the second transparent conductive film 46. Therefore, the pattern width of the metal film 47 is 30 μm. As described above, the pattern width of the metal film 47 with respect to the second transparent conductive film 46 can be determined in consideration of the maximum value of the positional deviation due to the alignment error. Then, the pattern design is performed so that the center of the pattern of the metal film 47 is arranged at the center of the pattern of the second transparent conductive film 46 in the width direction of the second connection wiring 36. As a result, the metal film 47 is disposed on the second transparent conductive film 46 without protruding from the second transparent conductive film 46 even if a maximum positional deviation of 5 μm occurs. Therefore, both ends of the pattern of the metal film 47 are disposed inside both ends of the pattern of the second transparent conductive film 46. Of course, the difference in pattern width between the second transparent conductive film 46 and the metal film 47 can be changed according to the maximum value of the positional deviation during pattern formation. In addition, the space | interval of the adjacent 2nd connection wiring 36 can be 20 micrometers, for example.

  Furthermore, when the metal film 47 is displaced by 5 μm from the second transparent conductive film 46 in the width direction of the second connection wiring 36 in the pattern width, the configuration shown in FIG. That is, as shown in FIG. 5C, in the width direction of the second connection wiring 36, the right end of the pattern of the metal film 47 is inside the right end of the pattern of the second transparent conductive film 46, and the pattern of the metal film 47 Of the second transparent conductive film 46 coincides with the left end of the pattern. Even in this case, the metal film 47 does not protrude from the second transparent conductive film 46 and is disposed only on the second transparent conductive film 46. That is, one end of the pattern of the metal film 47 is disposed on the second transparent conductive film 46 and inside the end of the second transparent conductive film 46, and one end of the pattern of the metal film 47 is the pattern of the second transparent conductive film. Matches the edge of Therefore, the metal film 47 is disposed in a flat place without a step. Thereby, generation | occurrence | production of the electrical failure by disconnection etc. can be suppressed.

  As shown in FIGS. 5B and 5C, even when the maximum misalignment occurs due to the alignment error, one end of the pattern of the metal film 47 is the end of the pattern of the second transparent conductive film 46. Place inside. Further, the other end of the pattern of the metal film 47 is arranged so as to coincide with the other end of the pattern of the second transparent conductive film 46, or the other end of the pattern of the metal film 47 is placed inside the pattern of the second transparent conductive film 46. Arrange to be. This can be realized by making the pattern width of the metal film 47 narrower than that of the transparent conductive film 47. As a result, one end of the pattern of the metal film 47 is disposed inside the second transparent conductive film 46. Further, the other end of the pattern of the metal film 47 is disposed on the second transparent conductive film 46. That is, the other end is disposed inside the pattern of the second transparent conductive film 46 or at the pattern end. Therefore, it is possible to suppress the occurrence of electrical failure due to disconnection or the like.

  Here, the operation of the input device 10 will be described. A fixed capacitor is formed at each intersection of the first electrode 31 and the second electrode 32. When the user brings a finger or the like close to the first electrode 31 in the effective area 33 from above the cover 11, the parasitic capacitance between the fingertip and the first electrode 31 and the parasitic capacitance of the human body are connected in parallel to the fixed capacitance. The Rukoto. As a result, the value of the combined capacitance changes, and the voltage across the fixed capacitance changes. By detecting this change in voltage with a detection circuit, the contacted position can be detected. When the user approaches an arbitrary position in the effective area 33 while the display element 20 is performing a predetermined display, processing based on the display is executed.

  Specifically, processing contents such as buttons and icons are displayed on the display screen of the display element 20. In this state, when the user brings a finger or the like into the effective area of the input device 10, the input device 10 detects the position. That is, the input device 10 determines coordinates in the effective area by the first electrode 31 and the second electrode. Then, the input device 10 associates the display area on the display element 20 with the effective area 33 and specifies the button or icon displayed at the contact position (coordinates). Thereby, the process according to the button and icon currently displayed on the display element 20 is performed. In this manner, the input device 10 performs input according to the position by associating the position in the effective area 33 with the display of the display element 20.

  With reference to FIG. 6, the manufacturing method of the display apparatus 100 using the electrode substrate 13 which concerns on this Embodiment is demonstrated. FIG. 6 is a flowchart for explaining a method of manufacturing display device 100 according to the present embodiment.

  First, as shown in FIG. 6, electrodes and connection wirings are formed on the transparent substrates 131 and 132 (step S101). Specifically, the first electrode 31, the second electrode 32, the first connection wiring 35, and the second connection wiring 36 are formed. Here, the first electrode 31 and the first connection wiring 35 are formed on the surface on the viewing side of the transparent substrate 131. The second electrode 32 and the second connection wiring 36 are formed on the surface of the transparent substrate 132 on the non-viewing side. That is, the second electrode 32 and the first electrode 31 are formed on the outer surface sides of the respective transparent substrates 131 and 12. The second electrode 32 and the second connection wiring 36 may be formed before the first electrode 31 and the first connection wiring 35 are formed, and after the first electrode 31 and the first connection wiring 35 are formed. The second electrode 32 and the second connection wiring 36 may be formed. As a method for forming the transparent conductive film and the metal film, for example, a DC sputtering method can be used. The process of forming the second electrode 32 and the second connection wiring 36 will be described later.

  Thereafter, the two transparent substrates 131 and 132 are bonded together with a sealing material (step S102). Specifically, the first electrode 31 forming surface of the transparent substrate 131 and the second electrode 32 forming surface of the transparent substrate 132 are bonded with a frame-shaped epoxy resin-based sealing material so as to face the outer surface.

  Then, the two bonded mother substrates are cut (step S103), and individual electrode substrates 13 are obtained. Thereafter, in each electrode substrate 13, the first FPC 15 is connected to the first connection wiring 35, and the second FPC 16 is connected to the second connection wiring 36 (step S104). The first FPC 15 and the second FPC 16 and the electrode substrate 13 can be connected by thermocompression bonding using an ACF (Anisotropic Conductive Film) or the like.

  Then, the cover 11 made of plastic, glass or the like is attached to the electrode substrate 13 by the adhesive layer 12 (step S105). Thereby, the input device 10 is completed. Then, the input device 10 and the display element 20 are bonded together by the adhesive layer 14 (step S106), and the operation and appearance are inspected (step S107), and the display device 100 is completed.

The transparent substrates 131 and 132 may be soda glass, alkali glass such as borosilicate glass, or non-alkali glass. Further, not only a glass substrate but also a plastic substrate may be used. Further, the transparent substrates 131 and 132 were immersed in a potassium nitrate (KNO ₃ ) solution at 400 ° C. or higher for about 10 hours to replace Na ⁺ ions present on the surface layer of the transparent substrates 131 and 132 with K ⁺ ions. It is also possible to use chemically strengthened glass.

  Next, the step of forming the second electrode 32 and the second connection wiring 36 in step S101 will be described with reference to FIG. FIG. 7 is a process cross-sectional view illustrating a process of forming the second electrode 32 and the second connection wiring 36.

  First, the second electrode 32 and the second transparent conductive film 46 to be the second connection wiring 36 are formed on the transparent substrate 132. As the second transparent conductive film 46, ITO having a thickness of 100 nm can be used. Then, before patterning the second transparent conductive film 46, a metal film 47 to be the second connection wiring 36 is formed on the second transparent conductive film 46. Thereby, as shown to Fig.7 (a), a laminated structure is formed. As the metal film 47, for example, an Al film having a thickness of 1 μm to 2 μm can be used. The second transparent conductive film 46 and the metal film 47 can be formed by sputtering or vapor deposition, for example. For example, the second transparent conductive film 46 and the metal film 47 may be continuously formed using an inline-type sputtering film forming apparatus.

  Next, the metal film 47 on the second transparent conductive film 46 is patterned. As a result, the configuration shown in FIG. Here, the pattern of the metal film 47 is formed only at the location that becomes the second connection wiring 36. A normal photolithography method can be used for patterning the metal film 47. That is, a resist which is a photosensitive resin is applied on the metal film 47, and is exposed and developed. As a result, a first resist pattern is formed on the metal film 47. Note that the first resist pattern is formed so as to remain in the portion where the second connection wiring 36 is formed. That is, the formation location of the second connection wiring 36 is covered with the first resist pattern. Then, after the metal film 47 is etched through the first resist pattern, the first resist pattern is peeled off. As a result, a pattern of the metal film 47 is formed at a location that becomes the second connection wiring 36. For the etching of the metal film 47, for example, wet etching can be used. At this stage, the second transparent conductive film 46 has not been patterned yet.

  Then, the second transparent conductive film 46 is patterned. A normal photolithography method can be used for patterning the second transparent conductive film 46. That is, a resist which is a photosensitive resin is applied on the metal film 47 and the second transparent conductive film 46, and is exposed and developed. As a result, a second resist pattern is formed on the metal film 47 and the second transparent conductive film 46. This second resist pattern is formed so as to completely cover the metal film 47. That is, the second resist pattern is disposed so as to protrude from the pattern of the metal film 47. That is, the second resist pattern is formed to be wider than the metal film 47 at a location to be the second connection wiring 36. Therefore, even when a positional shift due to an alignment error occurs in the step of forming the first resist pattern and the second resist pattern, the metal film 47 is not exposed from the second resist pattern. Accordingly, the second resist pattern protrudes from the metal film 47 and is also disposed on the second transparent conductive film 46. That is, the second resist pattern is arranged so as to straddle the pattern end of the metal film 47.

  Then, the second transparent conductive film 46 is etched. For example, wet etching can be used for patterning the second transparent conductive film 46. With the metal film 47 covered with the second resist pattern, the second transparent conductive film 46 is etched. Thereby, the pattern of the second transparent conductive film 46 under the metal film 47 is formed wider than the pattern of the metal film 47. That is, the metal film 47 is formed without protruding from the second transparent conductive film 46 in the width direction of the second connection wiring 36. As a result, a laminated structure of the second transparent conductive film 46 and the metal film 47 is formed at locations where the second electrode 32 and the second connection wiring 36 are to be formed. Then, by removing the second resist pattern, the process shown in FIG. In this way, the formation process of the second connection wiring 36 and the second electrode 32 is completed.

  Thus, the second electrode 32 and the second connection wiring 36 are formed in a desired pattern. That is, the second connection wiring 36 has a laminated structure of the second transparent conductive film 46 and the metal film 47, and the second electrode 32 has a single layer structure of the second transparent conductive film 46. Further, in the second connection wiring 36, the metal film 47 is disposed inside the pattern of the second transparent conductive film 46. Therefore, the pattern end is arranged on the second transparent conductive film 46 in the entire pattern of the metal film 47. Thereby, in the 2nd connection wiring 36, generation | occurrence | production of the electrical failure by disconnection etc. can be suppressed. Furthermore, since it can be formed by a simple process, productivity can be improved. In addition, since a resist made of an organic resin is not formed at the step portion between the second transparent conductive film 46 and the metal film 47, there is no gap between the resists, so that no etching solution penetrates. Therefore, the adhesion between the second transparent conductive film 46 and the metal film 47 can be improved, and the connection can be improved. Note that the first resist pattern may not be peeled before the second resist pattern is formed. That is, a resist to be the second resist pattern is applied in a state where the first resist pattern is formed. Then, with the first resist pattern remaining, exposure and development are performed to form a second resist pattern.

  Furthermore, as shown in FIG. 5C, even when the positional deviation is 5 μm, the metal film 47 does not protrude from the pattern of the second transparent conductive film 46. As described above, in the step of patterning the second transparent conductive film 46, one end of the pattern of the metal film 47 in the width direction of the second connection wiring 36 is disposed not inside the end of the pattern of the second transparent conductive film 46. It is patterned as follows. Further, the other end of the pattern of the metal film 47 in the width direction of the second connection wiring 36 is disposed on the second transparent conductive film 46 or matches the end of the pattern of the second transparent conductive film 46. Patterned. As described above, the metal film 47 is prevented from protruding from the second transparent conductive film 46 even when the maximum misalignment due to the alignment error occurs. The maximum value of the positional deviation may be determined according to the alignment accuracy of the exposure apparatus. For example, the pattern width of the second transparent conductive film 46 is preferably wider than the pattern width of the metal film 47 by 10 μm or more.

Thereafter, the first electrode 31 and the first connection wiring 35 are formed. That is, the first transparent conductive film 45 is formed and patterned by photolithography. Then, when the resist is removed by etching, the first electrode 31 and the first connection wiring 35 are formed. Note that the first electrode 31 and the first connection wiring 35 may be formed before the second electrode 32 and the second connection wiring 36. Furthermore, the etching of the first transparent conductive film 45 and the second transparent conductive film 46 may be performed in the same process. A protective film may be formed below the transparent conductive film. For example, an insulating layer such as SiO ₂ can be formed over the entire surface of the transparent substrates 131 and 132. As a method for forming the insulating layer, an RF sputtering method can be used.

  Note that the input device 10 according to the present invention is not limited to the one arranged on the viewing side of the display element 20. For example, the input device 10 may be arranged in front of a display board that fixedly displays characters, figures, symbols, etc. indicating the input contents. As the display board, a picture or a picture on which a keyboard or icon is described can be used. The first connection wiring 35 may have the same configuration as the second connection wiring 36.

It is a top view which shows the structure of the input device which concerns on embodiment. It is a top view which shows the structure of the electrode substrate which concerns on embodiment. It is a figure which shows the structure of the electrode of the one surface of the electrode substrate which concerns on embodiment. It is a figure which shows the structure of the electrode of the other surface of the electrode substrate which concerns on embodiment. It is sectional drawing which shows the structure of the 2nd connection wiring of the electrode substrate which concerns on embodiment. It is a flowchart explaining the manufacturing method of the electrode substrate which concerns on embodiment. FIG. 10 is a process cross-sectional view illustrating a manufacturing process of the second connection wiring in the method for manufacturing the input device according to the first embodiment.

Explanation of symbols

10 Input Device 11 Cover 12 Adhesive Layer 13 Electrode Substrate 14 Adhesive Layer 15 First FPC
16 Second FPC
20 display element 21 liquid crystal display panel 22 backlight unit 23 TFT array substrate 24 counter substrate 25 polarizing plate 26 polarizing plate 31 first electrode 32 second electrode 33 effective area 34 non-effective area 35 first connection wiring 36 second connection wiring 45 First transparent conductive film 46 Second transparent conductive film 47 Metal film 131 Transparent substrate 132 Transparent substrate

Claims (4)

An input device that performs input according to a position within an effective area,
A transparent substrate;
A transparent conductive film provided on the transparent substrate;
A transparent electrode formed by the transparent conductive film provided in the effective area;
Provided outside the effective area and connected to the transparent electrode; and
The connection wiring has the metal film formed on the transparent conductive film and the transparent conductive film,
One end of the pattern of the metal film in the width direction of the connection wiring is on the transparent conductive film, and is disposed at a position inside the pattern end of the transparent conductive film,
An input device in which the other end of the pattern of the metal film in the width direction of the connection wiring is disposed on the transparent conductive film.   The input device according to claim 1, wherein a pattern width of the transparent conductive film in a width direction of the connection wiring is 10 μm or more wider than a pattern width of the metal film. A transparent electrode provided in the effective area;
Provided outside the effective area and connected to the transparent electrode; and
A method for manufacturing an input device for performing input according to a position in the effective area,
Forming a transparent conductive film to be the transparent electrode and the connection wiring on a transparent substrate;
Forming a metal film pattern on the transparent conductive film;
After forming the pattern of the metal film, forming a pattern of the transparent conductive film,
In the step of forming the pattern of the transparent conductive film,
One end of the pattern of the metal film in the width direction of the connection wiring is disposed on the transparent conductive film and inside the end of the pattern of the transparent conductive film,
The manufacturing method of the input device which forms the pattern of the said transparent conductive film so that the other end of the pattern of the said metal film in the width direction of the said connection wiring may be arrange | positioned on the said transparent conductive film. In the step of forming the metal film pattern,
After forming the metal film, a first resist pattern is formed on the metal film, and the metal film pattern is formed by etching the metal film through the first resist pattern.
In the step of forming the pattern of the transparent conductive film,
Forming the second resist pattern on the metal film and the transparent conductive film;
The method of manufacturing an input device according to claim 3, wherein the pattern of the transparent conductive film is formed by etching the transparent conductive film through the second resist pattern.

Images