JP2004077998A - Conductive connection structure, electro-optical device, and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive connection structure capable of suppressing generation of a conductive connection defect even if the width and the pitch of a wiring are made narrow, to provide an electro-optical device provided with the conductive connection structure, to provide an electronic device and to provide a structure capable of reducing difficulty of probing and an inspection mistake. <P>SOLUTION: The width Wa of a connection wiring 122 of a flexible wiring board is constituted so as to be narrower than the gap Gb between the connection wirings. The width Wc of panel wirings 117 and 118 of a liquid crystal panel is constituted so as to be wider than the gap Gd between the panel wirings. The width Wc of the panel wirings 117 and 118 is constituted so as to be wider than the width Wa of the connection wiring 122. Thereby, even when deviation in positions of the liquid crystal panel and the flexible wiring board is generated in a wiring width direction, conductive connection between corresponding wirings is maintained in a wide range and danger of a shortcircuit between wirings adjacent to each other can be reduced. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a conductive connection structure, an electro-optical device, and an electronic apparatus, and more particularly to a conductive connection structure suitable for application to an electro-optical device having a flexible substrate connected to an electro-optical panel.
[0002]
[Prior art]
Generally, in an electro-optical device such as a liquid crystal display device or an EL (electroluminescence) device, a structure in which a flexible wiring board is conductively connected to a display (electro-optical panel) such as a liquid crystal panel or an EL panel is provided. There is a case where a display signal or a drive voltage is supplied to the above-mentioned display body from the outside through the interface.
[0003]
For example, in a liquid crystal display device 200 illustrated in FIG. 9, a substrate 211 and a substrate 214 made of glass, plastic, or the like are attached to each other with a sealant 219, and liquid crystals (not illustrated) are formed by the substrates 211 and 214 and the sealant 219. A liquid crystal panel 210 in which is enclosed is provided. A plurality of electrodes 212 are formed in stripes on the inner surface of the substrate 211 (surface on the substrate 214 side), and a plurality of electrodes 212 extend in a direction orthogonal to the electrodes 212 on the inner surface of the substrate 214 (surface on the substrate 211 side). Are formed in a stripe shape. The electrodes 212 and the electrodes 215 are arranged to face each other with the liquid crystal interposed therebetween, thereby forming a display area A in which a plurality of pixels are arranged vertically and horizontally.
[0004]
The substrate 211 is provided with a substrate overhang portion 211T that protrudes outward from an area overlapping the substrate 214. Panel wirings 217 and 218 electrically connected to the electrodes 212 and 215 are formed on the inner surface of the substrate overhang portion 211T so as to be drawn out beyond the display area A.
[0005]
A flexible wiring board 220 is connected and arranged on the inner surface of the board overhang portion 211T. The flexible wiring board 220 has an insulating base 221 made of a thin polyimide resin or the like, and connection wirings 222 formed along the insulating base 221. The connection wiring 222 is exposed toward the inner surface of the substrate overhang portion 211T at least in a range on the substrate overhang portion 211T, and is connected to the panel via an anisotropic conductive film (Anisotropic Conductive Film) not shown. It is conductively connected to the wirings 217 and 218.
[0006]
In conducting the conductive connection between the liquid crystal panel 210 and the flexible wiring board 220, a voltage is supplied to the panel wirings 217 and 218 of the liquid crystal panel 210 in advance to perform a lighting test to confirm that the liquid crystal panel 210 operates normally. . Thereafter, an anisotropic conductive film is placed on the panel wirings 217 and 218, and the flexible wiring substrate 220 aligned from above is pressed. Then, the flexible wiring board 220 is heated while pressurizing the flexible wiring board 220 using a pressure heating head or the like, so that the flexible wiring board 220 is electrically connected to the connection wiring via the anisotropic conductive film. It is fixed on the overhang portion 211T.
[0007]
[Problems to be solved by the invention]
However, in the liquid crystal display device 200, the number of electrodes 211 and 214 has increased in recent years as the definition and color of the display have advanced, and the number of panel wirings 217 and 218 also increases accordingly. are doing. In addition, increasing the area of a portion outside the display area A (so-called frame area) leads to an increase in the size of the liquid crystal display device. Is also difficult to increase. Therefore, in order to form a large number of panel wirings in a limited area, the widths (wiring widths) and intervals (wiring pitches) of the recent panel wirings 217 and 218 have been reduced to about several tens of μm. For this reason, it has become difficult to ensure the consistency of the positions of the liquid crystal panel 210 and the flexible wiring board 220 during the conductive connection work, and the conductive connection failure due to positional displacement between the two has increased, and the yield has increased. Is declining.
[0008]
In particular, since the wiring pitch has become smaller, one of the connection wirings 222 of the flexible wiring board 220 is not only connected to one of the corresponding panel wirings 217 and 218 but also to another panel wiring adjacent to the panel wiring. There is a high possibility that they will come into contact with each other, which is a major factor in increasing product defects.
[0009]
Further, the flexible wiring board 220 may be formed by a method of cutting out from a large-sized substrate having a larger area. In many cases, the end of the wiring 222 is deformed so as to spread in the width direction. Such a widening deformation of the end of the connection wiring 222 causes a short circuit of the connection wiring 222 to another panel wiring adjacent to the corresponding panel wiring due to a positional shift between the liquid crystal panel 210 and the flexible wiring board 220. It is known to promote.
[0010]
Further, for the same reason as described above, it is difficult to bring the inspection terminals of the inspection device into contact with the wirings 217 and 218 in the lighting inspection. As the inspection terminal, a prober having a plurality of probes arranged in parallel according to the arrangement pitch of the wirings 217 and 218 in advance is used. In this case, even if the wiring width and the wiring pitch are reduced as described above, it is difficult to reduce the probe diameter due to the difficulty of machining and the demand for the strength of the probe. As a result, the probe diameter becomes relatively large, and an inspection error such as a certain probe being in contact with a wire that should be in contact with another adjacent wire is likely to occur.
[0011]
Accordingly, the present invention is to solve the above problems, and an object of the present invention is to provide a conductive connection structure capable of suppressing occurrence of a conductive connection failure even when a wiring width and a wiring pitch are reduced, and the conductive connection structure. An object of the present invention is to provide an electro-optical device provided with an electronic device and an electronic apparatus. Another object of the present invention is to provide a structure capable of reducing probing difficulties and inspection errors even when a wiring width and a wiring pitch are reduced.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, a conductive connection structure according to the present invention includes a plurality of parallel first wires formed on a first substrate, and a plurality of parallel second wires formed on a second substrate. A conductive connection structure in which the first wiring and the second wiring corresponding to each other are conductively connected, wherein a width of the first wiring is larger than a gap between adjacent first wirings; The width of the second wiring is smaller than the gap between the adjacent second wirings, and the width of the first wiring is larger than the width of the second wiring.
[0013]
According to the present invention, in the conductive connection structure in which the first wiring formed on the first substrate and the second wiring formed on the second substrate are conductively connected, (1) the width of the first wiring is between the first wirings. (3) that the width of the second wiring is smaller than the gap between the second wirings, and (3) that the width of the first wiring is larger than the width of the second wiring. are doing. This is synonymous with satisfying (1) and (2) among the above three conditions if the parallel spacing of the first wiring and the parallel spacing of the second wiring are substantially the same. . In this case, the allowable width for the positional deviation between the first wiring and the second wiring for securing the conductive connection state is wider than when the above condition is not satisfied. Occurrence can be reduced.
[0014]
Here, it is preferable that the first wiring extends to a region that does not overlap with the second substrate beyond an outer edge of the second substrate. Thereby, even when the end shape of the second wiring is disturbed at the outer edge of the second substrate, a short circuit between adjacent terminals can be reduced. For example, when the second substrate is formed by cutting a large-sized substrate having a wiring pattern, the wiring may be distorted at the cutting end surface of the outer edge of the second substrate due to the cutting stress. It can be caused by being crushed. In this case, since the end shape of the second wiring is a shape widened in the width direction of the second wiring, the spread shape of the second wiring normally causes a short circuit to another second wiring adjacent to the corresponding first wiring. Increase the likelihood of However, in the present invention, the width of the second wiring is smaller than the width of the first wiring, and is smaller than the gap between adjacent second wirings (in other words, the gap between the second wirings). Therefore, even if the end of the second wiring has a shape deformed so as to spread in the width direction, a short circuit occurs with the first wiring adjacent to the first wiring to be originally connected. Possibility can be reduced.
[0015]
Next, another conductive connection structure according to the present invention includes a plurality of parallel first wires formed on a first substrate and a plurality of parallel second wires formed on a second substrate. A conductive connection structure in which the corresponding first wiring and the second wiring are conductively connected, wherein the first wiring extends to an area that does not overlap with the second substrate beyond an outer edge of the second substrate. The first wiring is characterized in that the first wiring has a narrow portion formed at a portion intersecting the outer edge of the second substrate in a plane and narrower than other portions.
[0016]
According to the present invention, when the inspection is performed by bringing the probe into contact with the narrow portion of the first wiring, the gap between the narrow portions can be sufficiently increased without increasing the area of the wiring region as compared with other portions. As a result, probing can be performed easily and inspection errors can be reduced. In addition, by having a narrow width portion at a portion that intersects the outer edge of the second substrate in a plane, even if the end shape of the second wiring is deformed at the outer edge of the second substrate by cutting stress or the like, Since the narrow portion has a smaller width than the other portions, and the gap between the narrow portions is increased thereby, it is possible to reduce a short circuit accident caused by deformation of the end shape.
[0017]
Further, a different conductive connection structure according to the present invention has a plurality of parallel first wires formed on a first substrate and a plurality of parallel second wires formed on a second substrate, and corresponds to each other. A conductive connection structure in which the first wiring and the second wiring are conductively connected, wherein the first wiring extends to an area that does not overlap with the second substrate beyond an outer edge of the second substrate. The first wiring has a narrow portion at a portion intersecting the outer edge of the second substrate in a plane, and overlaps with the second substrate, and the outer edge of the second substrate is larger than the narrow portion. A wide portion formed to be wider than the narrow portion on the side away from the narrow portion.
[0018]
According to the present invention, since the first wiring has the narrow width portion at the portion intersecting with the outer edge of the second substrate, the end shape of the second wiring is deformed at the outer edge of the second substrate so as to expand due to cutting stress or the like. Even if it is, the end of the second wiring is not the first wiring to be originally connected, but can be prevented from contacting another adjacent first wiring and causing a short circuit. Further, since the first wiring and the second wiring have a wide portion in a conductively connected region, the allowable width for the positional deviation between the first wiring pattern and the second wiring pattern is increased, and the conductive connection failure is reduced. Occurrence can be reduced.
[0019]
In the present invention, the width of the narrow portion is preferably smaller than the gap between the adjacent narrow portions, and the width of the wide portion is preferably larger than the gap between the adjacent wide portions. As a result, the allowable range for the positional deviation between the first wiring and the second wiring for securing the conductive connection state is expanded as compared with a case where the above condition is not satisfied. It can be further reduced.
[0020]
Next, the electro-optical device of the present invention is a first substrate that holds an electro-optical material, an electrode provided in a region of the first substrate where the electro-optical material is arranged, and is conductively connected to the electrode, A plurality of first wirings drawn out in parallel beyond the region, a second substrate having a portion opposed to the first wirings, and a plurality of first wirings each electrically connected to the plurality of first wirings; A width of the first wiring is larger than a gap between adjacent first wirings, at least in a portion where the first wiring and the second wiring are conductively connected. The width of the second wiring is smaller than the gap between the adjacent second wirings, and the width of the first wiring is larger than the width of the second wiring.
[0021]
According to the present invention, the allowable range for the positional deviation between the first wiring and the second wiring for securing the conductive connection state is wider than when the above condition is not satisfied. Can be reduced.
[0022]
Further, in the first substrate holding the electro-optical material, if the electrode material and the wiring material are to be formed of the same material, the selection range of the material of the first wiring is limited. However, since there is almost no restriction on the wiring material for the second wiring provided on the second substrate, for example, a low electrical resistivity material such as a metal material can be used. Therefore, there is an advantage that the increase in the wiring resistance of the first wiring can be relatively suppressed by making the width of the first wiring larger than the width of the second wiring.
[0023]
In this case, it is preferable that the first wiring extends to a region that does not overlap with the second substrate beyond the outer edge of the second substrate. In such a configuration, if the end shape of the second wiring is disturbed at the outer edge of the second substrate, a short circuit may occur to wiring other than the corresponding wiring. Since the width of the second wiring is configured to be smaller than the width of the first wiring and smaller than the gap between the second wirings, the occurrence of the short circuit can be reduced.
[0024]
Next, another electro-optical device according to the present invention includes a first substrate for holding an electro-optical material, an electrode provided in a region of the first substrate where the electro-optical material is arranged, and a conductive connection to the electrode. A plurality of first wirings drawn out in parallel beyond the region, a second substrate having a portion arranged to face the first wirings, and a plurality of conductive wirings respectively connected to the plurality of first wirings. And a second wiring, wherein the first wiring extends to a region which does not overlap with the second substrate beyond an outer edge of the second substrate, and wherein the first wiring has an outer edge of the second substrate. A narrower portion formed narrower than other portions in a portion that intersects with a plane in plan view.
[0025]
According to the present invention, when an inspection is performed by bringing a probe into contact with a narrow portion during an electrical inspection such as a lighting inspection, a gap between wirings can be formed in a narrow portion without increasing the area of a wiring region. Can be secured larger than other parts, so that probing can be easily performed and inspection errors due to probing failure can be reduced. In addition, by having a narrow width portion at a portion that intersects the outer edge of the second substrate in a plane, even if the end shape of the second wiring is deformed at the outer edge of the second substrate by cutting stress or the like, Since the narrow portion has a smaller width than the other portions, and the gap between the narrow portions is increased thereby, it is possible to reduce a short circuit accident caused by deformation of the end shape.
[0026]
Next, a different electro-optical device according to the present invention includes a first substrate for holding an electro-optical material, an electrode provided in a region of the first substrate on which the electro-optical material is arranged, and an electro-conductively connected electrode. A plurality of first wirings drawn out in parallel beyond the region, a second substrate having a portion arranged to face the first wirings, and a plurality of first wirings electrically connected to the plurality of first wirings, respectively. The first wiring extends to a region that does not overlap with the second substrate beyond the outer edge of the second substrate, and the first wiring is connected to the outer edge of the second substrate. A wide portion having a narrow portion at an intersecting portion, overlapping with the second substrate, and formed wider than the narrow portion on a side farther from the outer edge of the second substrate than the narrow portion. It has a part.
[0027]
According to the present invention, since the first wiring has the narrow portion at the portion that intersects the outer edge of the second substrate, the gap between the narrow portions can be reduced to some extent without increasing the area of the wiring region. It is possible to secure a large amount. Therefore, even if the end shape of the second wiring is deformed at the outer edge of the second substrate so as to expand due to cutting stress or the like, the end of the second wiring is not the first wiring to be originally connected but is adjacent to the other end. Can be prevented from contacting the first wiring. Further, since the first wiring has a wide portion in a region conductively connected to the second wiring, an allowable width for a positional shift between the first wiring and the second wiring is increased, and the conductive connection failure is reduced. Occurrence can be reduced.
[0028]
Here, the width of the narrow portion is preferably smaller than the gap between the adjacent narrow portions, and the width of the wide portion is preferably larger than the gap between the adjacent wide portions. Since the width of the narrow portion is smaller than the gap between the narrow portions, a short circuit due to the end shape of the second wiring can be further reduced. Further, since the width of the wide portion is larger than the gap between the wide portions, the allowable range for the positional deviation between the first wiring and the second wiring for securing the conductive connection state is further increased. Can be further reduced.
[0029]
In the present invention, it is preferable that the second substrate is a substrate having higher flexibility than the first substrate. Since the second substrate is a highly flexible substrate, electrical connection to a panel (display body) including the first substrate that holds the electro-optical material can be configured more easily. The second substrate is preferably a flexible wiring substrate in which an insulating base material such as a polyimide resin is formed in a thin sheet shape. As described above, when the second substrate is a highly flexible substrate, it is necessary to secure a large gap between the wirings in order to prevent a short circuit or a leak between the second wirings in the wiring pattern. The configuration of each of the above-mentioned inventions, that is, the configuration in which the width of the second wiring is smaller than the gap between the second wirings is particularly effective. Further, in the second substrate formed of a flexible wiring substrate or the like, unlike the first wiring provided on the first substrate holding the electro-optical material, a low electrical resistivity material such as a metal material is used as a material of the second wiring. Since it can be used without hindrance, there is also an advantage that a problem (that is, an increase in wiring resistance) hardly occurs even when the width of the second wiring is reduced.
[0030]
Next, an electronic apparatus according to another aspect of the invention includes any one of the above-described electro-optical devices and a control unit that controls the electro-optical device. Thereby, even when the electro-optical device is made high definition or colorized, stability and reliability of an electrical connection state to the electro-optical device via the second substrate can be ensured. Further, since it is possible to cope with a reduction in the wiring pitch, it is possible to make the electro-optical device compact by reducing the size of the wiring region.
[0031]
In each of the above inventions, it is preferable that the first wiring and the second wiring are formed at substantially the same parallel interval. Thus, a compact conductive connection structure in which the first wiring and the second wiring are conductively connected in a one-to-one relationship can be configured.
[0032]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of a conductive connection structure, an electro-optical device, and an electronic apparatus according to the present invention will be described in detail with reference to the accompanying drawings.
[0033]
[First Embodiment]
FIG. 1 is a plan view and a partially enlarged plan view of a liquid crystal display device 100 which is an electro-optical device according to a first embodiment of the present invention. FIG. 3 is a schematic partial sectional view schematically showing a partial sectional structure of the liquid crystal display device 100. As shown in FIG. 1, the liquid crystal display device 100 includes a liquid crystal panel 110, and a flexible wiring board (corresponding to the above-mentioned second substrate) 120 which is conductively connected to the liquid crystal panel 110. The liquid crystal panel 110 has a cell structure in which substrates 111 and 114 made of glass, plastic, or the like are bonded with a sealant 119. The liquid crystal 110LC shown in FIG. 3 is sealed inside the cell structure. The substrate 111 has a substrate overhang portion 111T that extends outward from the outer edge of the substrate 114.
[0034]
A plurality of electrodes 112 are formed on the inner surface of the substrate 111. These electrodes 112 are formed in a strip shape, and are arranged in a stripe shape in parallel with each other. The electrode 112 is made of a transparent conductor such as ITO (indium tin oxide). The electrode 112 is formed integrally with a panel wiring (corresponding to the first wiring) 117 formed so as to be drawn out from the display area A onto the inner surface of the substrate overhang portion 111T of the substrate 111, and is formed of the same material. Have been. The panel wiring 117 extends on the inner surface of the substrate overhang portion 111T and extends to the edge of the substrate 111.
[0035]
As shown in FIG. 3, an alignment film 113 made of a polyimide resin or the like is formed on the substrate 112 on the substrate 111. The alignment film 113 is for imparting initial alignment characteristics to the liquid crystal 110LC, and has been subjected to an alignment process such as a rubbing process.
[0036]
On the other hand, a plurality of electrodes 115 are formed on the inner surface of the substrate 114. These electrodes 115 are formed in a strip shape extending in a direction orthogonal to the electrodes 112, and are formed in a stripe shape in parallel with each other. This electrode 115 is also made of a transparent conductor such as ITO. The electrode 115 is disposed in the display area A so as to face the electrode 112, and an intersection area between the electrodes 112 and 115 forms a pixel. These pixels are arranged in a matrix in the display area A vertically and horizontally.
[0037]
The electrode 115 is integrated with a part of the panel wiring (corresponding to the above-described first wiring) 118 drawn out from the display area A, that is, the wiring part 118A, and is made of the same material. The wiring 118 has the wiring portion 118A formed on the inner surface of the substrate 114 and the wiring portion 118B formed on the inner surface of the substrate 111. The wiring portions 118A and 118B are conductively connected by forming the sealing material 119 from an anisotropic conductive material and using the sealing material 119 as a vertical conductive portion. For example, by using a material in which conductive particles are dispersed and arranged in a resin base material as the sealant 119, the structure can be made to exhibit conductive anisotropy. Note that the conductive connection between the wiring portions 118A and 118B may be performed by an upper and lower conductive portion made of an anisotropic conductive material other than the sealing material 119 or another conductive material. The wiring portion 118B extends so as to be drawn out from the upper and lower conductive portions onto the inner surface of the substrate overhang portion 111T, and extends to the end of the substrate 111 in parallel with the panel wiring 117.
[0038]
Here, FIG. 1 schematically shows the layout of electrodes and wirings formed on the liquid crystal panel 110. Although only a small number of electrodes and wirings are shown in FIG. And the wiring are in parallel. Further, the above-described wiring portion 118B formed on the inner surface of the substrate overhang portion 111T is simply referred to as a panel wiring 118 in the following description.
[0039]
The flexible wiring board 120 has an insulating base 121 made of a thin sheet of polyester resin, polyimide resin, or the like, and a plurality of connection wirings 122 formed on the insulating base 121. The thickness of the insulating base 121 is preferably 50 to 500 μm. Further, it is desirable that the connection wiring 122 be formed of a metal such as copper or aluminum, or a material having a low electrical resistivity equivalent thereto. In a region where the liquid crystal panel 110 and the flexible wiring board 120 are conductively connected, the parallel spacing of the connection wiring 122 is substantially the same as the parallel spacing of the panel wirings 117 and 118. In this region, the corresponding panel wirings 117 and 118 and the connection wiring 122 are conductively connected one-to-one via an anisotropic conductive film (Anisotropic Conductive Film) 130 shown in FIG. As the anisotropic conductive film 130, for example, a material in which conductive particles (eg, metal particles) are dispersed in an insulating resin can be used.
[0040]
In the present embodiment, as shown in a partially enlarged plan view of FIG. 1, narrow connection wiring 122 is conductively connected to wide panel wirings 117 and 118. 1 and 3 are perspective views showing the insulating base material 121 of the flexible wiring board 120 as being transparent for convenience of illustration, but the actual insulating base material 121 needs to be transparent. There is no. The panel wirings 117 and 118 are preferably made of the same material at the same time as the electrodes 112 and 115 as described above. In this case, the transparent conductor, which is an electrode material, generally has a higher resistivity than the metal conductor, so that it is necessary to secure a certain width to reduce the wiring resistance, whereas the flexible wiring substrate Since the connection resistance 122 of the 120 can be made of a low electrical resistivity material such as a metal conductor, it can be configured to be narrower than the panel wiring. Further, in the flexible wiring board 120, it is necessary to secure a large gap between the wirings in order to prevent a short circuit and a leak between the wirings. However, since the connection wiring 122 is configured to be narrow as described above, This is advantageous because a large gap can be provided between the connection wirings 122.
[0041]
FIG. 5 is a plan view showing a conductive connection structure between the panel wirings 117 and 118 and the connection wiring 122. In the present embodiment, the width Wa of the connection wiring 122 is configured to be smaller than the gap Gb between the connection wirings. The width Wc of the panel wirings 117 and 118 is configured to be larger than the gap Gd between the panel wirings. Further, as described above, the width Wc of the panel wirings 117 and 118 is configured to be larger than the width Wa of the connection wiring 122.
[0042]
As described above, by being configured to satisfy the conditions of (1) Wa <Gb, (2) Wc> Gd, and (3) Wc> Wa, between the liquid crystal panel 110 and the flexible wiring board 120, In addition, even when a positional shift occurs in the wiring width direction (the horizontal direction in the drawing), the conductive connection state between the corresponding wirings is maintained in a wide range, and the risk of short-circuiting to adjacent wirings is reduced. That is, a large allowable width (margin) for the positional deviation between the liquid crystal panel 110 and the flexible wiring board 120 can be secured.
[0043]
Specific examples of the dimensions of the panel wirings 117 and 118 and the connection wiring 122 are as follows. The width Wc of the panel wiring is 40 to 70 μm (eg, 55 μm), the gap Gd between the panel wirings is 5 to 15 μm (eg, 10 μm), the width Wa of the connection wiring is 15 to 30 μm (eg, 22 μm), and the gap Gb between the connection wirings is It is 30 to 50 μm (for example, 42 μm).
[0044]
Also, as shown in FIGS. 1, 3 and 5, in the present embodiment, the panel wirings 117 and 118 exceed the outer edge 120E of the flexible wiring board 120 and do not overlap with the flexible wiring board 120 (FIGS. 1 and 3). On the substrate overhanging portion 111T shown in FIG. 2 and on the display area A side of the flexible wiring board 120, more specifically, the area between the outer edge 120E of the flexible wiring board 120 and the board end 114E of the board 114. ). In this case, an end 122 a of the connection wiring 122 exists at the outer edge 120 E of the flexible wiring board 120. In many cases, the end 122a of the connection wiring 122 is deformed into a shape slightly wider than the wiring width Wa. The deformation of the end portion 122a is caused when the cutting stress is applied to the connection wiring and crushed when the flexible wiring substrate 120 is cut out from the large-sized substrate. Normally, when the end 122a of the connection wiring 122 is deformed into such a slightly widened shape, a short circuit occurs not to the panel wirings 117 and 118 which should be conductively connected but to another panel wiring adjacent thereto. Is more likely to occur. However, in the present embodiment, since the width Wa of the connection wiring is smaller than the panel wiring Wc, and the width Wa is smaller than the gap Gb, even if the end 122a of the connection wiring 122 is slightly widened, the short circuit occurs. Accidents can be suppressed.
[0045]
[Second embodiment]
Next, a second embodiment according to the present invention will be described with reference to FIGS. FIG. 2 is a plan view and a partially enlarged plan view of a liquid crystal display device 100 'which is an electro-optical device according to a second embodiment of the invention, FIG. 4 is an enlarged partial cross-sectional view of the device, and FIG. It is an enlarged partial plan view.
[0046]
In the present embodiment, a substrate 111, an electrode 112, an alignment film 113, a substrate 114, an electrode 115, an alignment film 116, a sealing material 119, a liquid crystal 110LC, an insulating base material 121, and a connection wiring 122 similar to those in the first embodiment are provided. Since the flexible wiring board 120 is provided, the same reference numerals are given to these and the description is omitted.
[0047]
On the liquid crystal panel 110 'of the liquid crystal display device 100', panel wirings 117 'and 118' different from those of the first embodiment are formed. In these panel wirings 117 ′ and 118 ′, narrow portions 117X and 118X are formed in regions intersecting with the outer edge 120E of the flexible wiring board 120. Further, wide portions 117Y and 118Y formed wider than the narrow portions 117X and 118X are provided in a region opposite to the outer edge 120E with respect to the narrow portions 117X and 118X. The panel wirings 117 'and 118' extend toward the display area A beyond the outer edge 120E of the flexible wiring board 120 and are connected to the electrodes 112 and 115 in the display area A. It is provided at least up to the vicinity of the substrate end 114E of the substrate 114.
[0048]
Further, as shown in FIG. 4, the panel wirings 117 ′ and 118 ′ of the present embodiment include base layers 117m and 118m made of a metal material (low electric resistivity material) such as aluminum or silver alloy, and ITO or the like. (A two-layer structure) with surface layers 117i and 118i made of a transparent conductor (the same material as the electrodes). In the illustrated example, this laminated structure is formed in the entire region on the substrate overhang portion 111T, but is preferably formed at least in the range of the narrow portions 117X and 118X. Thus, the wiring resistance of the panel wiring can be reduced irrespective of the presence of the narrow portions 117X and 118X. The base layers 117m and 118m are entirely covered with the surface layers 117i and 118i including the side surfaces, and are completely sealed by the surface layers 117i and 118i and the substrate 111 (substrate overhang 111T). This is preferable for improving the corrosion resistance of the base layers 117m and 118m. This is particularly effective when the base layer is made of a material having low corrosion resistance such as silver or a silver alloy.
[0049]
In this embodiment, at least part of the panel wiring has a laminated structure as shown in FIG. 4, but instead, the panel wiring may have a single-layer structure shown in FIG. . Further, at least a part of the panel wiring of the first embodiment may have the same laminated structure as that of the present embodiment.
[0050]
In the present embodiment, as shown in FIG. 6, in the panel wirings 117 ′ and 118 ′, the width Wc1 of the narrow portions 117X and 118X is smaller than the width Wc2 of the wide portions 117Y and 118Y. Correspondingly, in the region where the narrow portions 117X and 118X are formed, the gap Gd1 between the narrow portions is larger than the gap Gd2 between the wide portions. Therefore, if the probe is brought into contact with the narrow portion during the lighting inspection of the liquid crystal panel 110 ', probing is facilitated, and inspection errors such as short-circuiting between adjacent wirings are reduced. effective. The probing may be performed on any portion of the narrow width portion, but it is preferable that the probing be performed so as not to affect the conductive connection state to the flexible wiring substrate 120 performed later (that is, the panel in a range that overlaps the flexible wiring substrate 120 in a plane). In order not to damage the surface of the wiring), it is desirable to perform the processing on the narrow portion in the region between the outer edge 120E of the flexible wiring substrate 120 and the substrate end 114E of the substrate 114.
[0051]
The lighting inspection is performed before mounting the flexible wiring board 120. However, in the case of the present embodiment, since the narrow portions 117X and 118X are also exposed in a region between the outer edge 120E of the flexible wiring substrate 120 and the substrate end 114E of the substrate 114, the flexible wiring substrate is extended. Even after the mounting of the LED 120, the lighting inspection can be performed as long as the area is not molded.
[0052]
Further, in the present embodiment, since the narrow portions 117X and 118X are provided in portions that intersect the outer edge 120E of the flexible wiring board 120 in a plane, the end 122a of the connection wiring 122 at the outer edge 120E of the flexible wiring board 120. Is deformed so as to spread in the width direction as described above, since the end 122a is conductively connected to the narrow portions 117X and 118X of the panel wiring, the width of the narrow portion is small, and Since the gap between the width portions is large, the occurrence of short-circuit failure can be further reduced as compared with the case of the first embodiment.
[0053]
Furthermore, in the present embodiment, the connection wiring 122 of the flexible wiring board 120 is conductively connected to the wide portions 117Y and 118Y of the panel wirings 117 ′ and 118 ′. There is an advantage that the allowable width for the deviation can be increased and the conductive connection failure can be reduced. For example, even if the connection wiring 122 is not conductively connected to the narrow portions 117X and 118X due to positional displacement, the connection wiring 122 may be conductively connected to the wide portions 117Y and 118Y. The effect of providing the width portion can be almost eliminated. In particular, when the width Wc2 of the wide portion, the gap Gd2 between the wide portions, the width Wa of the connection wiring, and the gap Gb between the connection wirings are used, as in the first embodiment, (1) Wa <Gb, (2) It is preferable to satisfy the conditions of Wc2> Gd2 and (3) Wc2> Wa.
[0054]
More specifically, the width Wc1 of the narrow portion of the panel wiring is 35 to 50 μm (for example, 44 μm), the gap Gd1 between the narrow portions is 15 to 30 μm (for example, 21 μm), and the width Wc2 of the wide portion is 40 to 70 μm ( The gap Gd2 between the panel wirings is 5 to 15 μm (for example, 10 μm), the width Wa of the connection wiring is 15 to 30 μm (for example, 22 μm), and the gap Gb between the connection wirings is 30 to 50 μm (for example, 42 μm).
[0055]
[Electronics]
Finally, an embodiment of an electronic apparatus including the electro-optical device (liquid crystal display device) of each of the above embodiments will be described. FIG. 7 is a schematic configuration diagram illustrating the overall configuration of the present embodiment. The electronic device shown here includes the same liquid crystal display device 100 as described above, and control means 1200 for controlling the same. Here, the liquid crystal display device 100 includes a liquid crystal panel 110, a flexible wiring board 120, and a driving circuit that is mounted on the flexible wiring board 120 or connected to the flexible wiring board 120 and configured by a semiconductor IC or the like. 150 are included. The control means 1200 includes a display information output source 1210, a display processing circuit 1220, a power supply circuit 1230, and a timing generator 1240.
[0056]
The display information output source 1210 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 for synchronizing and outputting a digital image signal. And is configured to supply display information to the display information processing circuit 1220 in the form of an image signal or the like in a predetermined format based on various clock signals generated by the timing generator 1240.
[0057]
The display information processing circuit 1220 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. Is supplied to the drive circuit 150 together with the clock signal CLK. The driving circuit 150 includes a scanning line driving circuit, a data line driving circuit, and an inspection circuit. The power supply circuit 1230 supplies a predetermined voltage to each of the above-described components.
[0058]
FIG. 8 shows a mobile phone as one embodiment of the electronic apparatus according to the present invention. In this mobile phone 1000, a circuit board 1001 is arranged inside a case body 1010, and the above-described liquid crystal display device 100 is mounted on the circuit board 1001. Operation buttons 1020 are arranged on the front surface of the case body 1010, and an antenna 1030 is mounted to be able to protrude and retract from one end. A speaker is arranged inside the receiver 1040, and a microphone is built inside the transmitter 1050. The liquid crystal display device 100 installed in the case body 1010 is configured so that the display surface (the above-described display area A) can be visually recognized through the display window 1060.
[0059]
Note that the electro-optical device and the electronic apparatus of the present invention are not limited to the illustrated examples described above, and it is needless to say that various changes can be made without departing from the gist of the present invention. For example, the liquid crystal panel shown in each of the above embodiments basically has a simple matrix type structure. However, an active matrix type using an active element (active element) such as a TFT (thin film transistor) or TFD (thin film diode) is used. The present invention can be applied to a liquid crystal device. Further, the liquid crystal panel of the above embodiment has a so-called COF (Chip On Film) type structure, but may have a structure in which an IC chip is directly mounted.
[0060]
In the above-described embodiment, a case where the present invention is applied to a liquid crystal device as an electro-optical device has been described. However, the present invention is not limited to this. Display devices, FED (field emission display) devices, LED (light emitting diode) display devices, electrophoretic display devices, thin CRTs, small televisions using liquid crystal shutters, etc., devices using digital micromirror devices (DMD), etc. It can be applied to various electro-optical devices.
[0061]
【The invention's effect】
As described above, according to the present invention, in a conductive connection structure between patterns having a plurality of wirings, an allowable width for positional deviation can be increased, so that a conductive connection state can be reliably obtained, and The yield can be improved. Further, even if the end shape of the second wiring is deformed so as to spread due to cutting stress or the like at the outer edge of the second substrate, occurrence of a short circuit accident can be reduced. Further, by performing an inspection on the narrow portion, a short circuit or the like at the time of the inspection can be prevented, so that the inspection can be easily performed and an inspection error can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic plan view and a partially enlarged plan view illustrating a planar shape of an electro-optical device according to a first embodiment of the invention.
FIGS. 2A and 2B are a schematic plan view and a partially enlarged plan view illustrating a planar shape of an electro-optical device according to a second embodiment of the invention.
FIG. 3 is a partially enlarged cross-sectional view of the first embodiment.
FIG. 4 is a partially enlarged sectional view of a second embodiment.
FIG. 5 is a plan view showing a conductive connection structure according to the first embodiment.
FIG. 6 is a plan view showing a conductive connection structure according to a second embodiment.
FIG. 7 is a schematic configuration diagram of a display system of the electronic apparatus according to the embodiment of the invention.
FIG. 8 is a schematic perspective view illustrating an appearance of a mobile phone as an example of an electronic apparatus.
FIG. 9 is a schematic perspective view showing the appearance of a conventional liquid crystal display device.
[Explanation of symbols]
100, 100 '... liquid crystal display device
110, 110 '・ ・ ・ Liquid crystal panel
111, 114 ... substrate
112, 115 ... electrodes
113, 116 ・ ・ ・ Alignment film
117, 118 ・ ・ ・ Panel wiring
119 ・ ・ ・ Seal material
120: Flexible wiring board
121 ... insulating base material
122 ... connection wiring
117X, 118X ... narrow width part
117Y, 118Y ... wide part

Claims (12)

It has a plurality of parallel first wirings formed on a first substrate and a plurality of parallel second wirings formed on a second substrate, and the first wiring and the second wiring corresponding to each other are different from each other. A conductive connection structure formed by conductive connection,
A width of the first wiring is larger than a gap between adjacent first wirings;
A width of the second wiring is smaller than a gap between adjacent second wirings;
A conductive connection structure, wherein the width of the first wiring is larger than the width of the second wiring. 2. The conductive connection structure according to claim 1, wherein the first wiring extends beyond an outer edge of the second substrate to a region that does not overlap with the second substrate. 3. It has a plurality of parallel first wirings formed on a first substrate and a plurality of parallel second wirings formed on a second substrate, and the first wiring and the second wiring corresponding to each other are different from each other. A conductive connection structure formed by conductive connection,
The first wiring extends to an area that does not overlap with the second substrate beyond an outer edge of the second substrate;
The conductive connection structure according to claim 1, wherein the first wiring has a narrow portion formed at a portion intersecting the outer edge of the second substrate in a plane, narrower than other portions. It has a plurality of parallel first wirings formed on a first substrate and a plurality of parallel second wirings formed on a second substrate, and the first wiring and the second wiring corresponding to each other are different from each other. A conductive connection structure formed by conductive connection,
The first wiring extends to an area that does not overlap with the second substrate beyond an outer edge of the second substrate;
The first wiring has a narrow portion at a portion that intersects the outer edge of the second substrate in a plane, overlaps the second substrate, and is further away from the outer edge of the second substrate than the narrow portion. A conductive portion having a wide portion formed wider than the narrow portion. The width of the narrow portion is smaller than the gap between the adjacent narrow portions, and the width of the wide portion is larger than the gap between the adjacent wide portions. 4. The conductive connection structure according to 1. A first substrate for holding an electro-optical material,
An electrode provided in a region of the first substrate where the electro-optical material is arranged;
A plurality of first wirings that are conductively connected to the electrode and are drawn out in parallel beyond the region;
A second substrate having a portion opposed to the first wiring;
A plurality of second wirings formed on the second substrate and conductively connected to the plurality of first wirings, respectively;
At least in a portion where the first wiring and the second wiring are conductively connected, the width of the first wiring is larger than the gap between adjacent first wirings, and the width of the second wiring is adjacent. An electro-optical device, wherein the width of the first wiring is larger than the width of the second wiring. 7. The electro-optical device according to claim 6, wherein the first wiring extends beyond an outer edge of the second substrate to a region that does not overlap with the second substrate. A first substrate for holding an electro-optical material,
An electrode provided in a region of the first substrate where the electro-optical material is arranged;
A plurality of first wirings that are conductively connected to the electrode and are drawn out in parallel beyond the region;
A second substrate having a portion opposed to the first wiring;
A plurality of second wirings formed on the second substrate and conductively connected to the plurality of first wirings, respectively;
The first wiring extends to an area that does not overlap with the second substrate beyond an outer edge of the second substrate;
The electro-optical device according to claim 1, wherein the first wiring has a narrow portion formed to be narrower than other portions in a portion intersecting the outer edge of the second substrate in a plane. A first substrate for holding an electro-optical material,
An electrode provided in a region of the first substrate where the electro-optical material is arranged;
A plurality of first wirings that are conductively connected to the electrode and are drawn out in parallel beyond the region;
A second substrate having a portion opposed to the first wiring;
A plurality of second wirings conductively connected to the plurality of first wirings, respectively;
The first wiring extends to an area that does not overlap with the second substrate beyond an outer edge of the second substrate;
The first wiring has a narrow portion at a portion that intersects with the outer edge of the second substrate, overlaps the second substrate, and is further away from the outer edge of the second substrate than the narrow portion. An electro-optical device having a wide portion formed wider than the narrow portion. The width of the narrow portion is smaller than the gap between the adjacent narrow portions, and the width of the wide portion is larger than the gap between the adjacent wide portions. The electro-optical device according to any one of the above. The electro-optical device according to claim 6, wherein the second substrate is a substrate having higher flexibility than the first substrate. An electronic apparatus comprising: the electro-optical device according to claim 6; and control means for controlling the electro-optical device.

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