JP2965979B2 - Wiring substrate, array substrate of display device, liquid crystal display device provided with array substrate, and method of manufacturing wiring substrate and array substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring substrate having a plurality of wirings provided on an insulating substrate, an array substrate used for a flat display panel and the like, a liquid crystal display device provided with the array substrate, and a wiring substrate and an array. The present invention relates to a method for manufacturing a substrate.

[0002]

2. Description of the Related Art In recent years, flat panel displays represented by liquid crystal display devices have been developed with a view to miniaturization, light weight, and low power consumption. The liquid crystal display device includes an array substrate and a counter substrate which are arranged to face each other with a liquid crystal layer interposed therebetween. In the array substrate, a plurality of signal lines and scanning lines are arranged in a matrix on a green substrate, and pixel electrodes provided in each area surrounded by the signal lines and scanning lines are scanned with the signal lines via switching elements. It is configured by connecting to the intersection with the line. The counter substrate is configured by providing a counter electrode made of a transparent electrode material on an insulating substrate.

The signal lines and the scanning lines on the array substrate are respectively drawn out of the display area, are connected to the power supply electrodes provided on the side edges of the array substrate, and are externally connected via these power supply electrodes. It is electrically connected to a drive circuit and the like.

In such a liquid crystal display device, recently, in order to secure a large display area with respect to the external dimensions,
There is a demand for a narrower frame, that is, a smaller holding frame around the effective display area. Further, further cost reduction is required, and further improvement in product yield is required.

However, when the frame of the liquid crystal display device is narrowed, the installation area of the wiring drawn out from the display area becomes narrow, so that the wiring width and the distance between the wirings must be narrowed. Failures such as short-circuits are likely to occur.

Therefore, in recent years, in order to improve the reliability with respect to open wiring, for example, a liquid crystal display device having a two-layer wiring structure in which a portion of a signal line extending outward from a display area is provided. That is, the lead portion of the signal line is connected to the first wiring and the second wiring, which are formed by lamination via the insulating layer.
And wiring. The end portions of the first and second wirings on the display region side and the end portions of the power supply electrode side are electrically connected to each other via through holes. With such a two-layer wiring structure, the connection state of the signal lines can be maintained even when one of the first and second wirings is broken, and reliability can be improved.

[0007]

However, in the case of a two-layer wiring structure as described above, the reliability of open wiring is improved, but the number of wirings is doubled and the probability of occurrence of short circuit between wirings is also increased. It will be doubled. Especially,
When the frame of the liquid crystal display device is made narrower, the installation space for the wiring lead-out portion becomes narrower, and a short circuit between the wirings is more likely to occur.

When a short circuit occurs between wirings,
It is difficult to detect the short-circuit position and to cut the short-circuit wiring, which is a factor that hinders automation of liquid crystal display device manufacturing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide a wiring substrate, an array substrate of a display device, and a liquid crystal display having an array substrate which can realize high quality, high yield, and low cost. It is an object of the present invention to provide an apparatus and a method for manufacturing a wiring substrate and an array substrate.

[0010]

In order to achieve the above object, a wiring board according to the present invention comprises an insulating substrate and a plurality of wirings provided on the insulating substrate, each of the wirings being: A first wiring and a second wiring stacked via an insulating film;
At least two conductive portions electrically connected between the first wiring and the second wiring at at least two places, and provided between the conductive portions; and the first wiring and the second And a wiring having at least two repair regions which are shifted from each other in a surface direction of the insulating substrate.

An array substrate of a display device according to the present invention includes an insulating substrate, a plurality of wirings provided on the insulating substrate, and a display region provided on the insulating substrate. A plurality of pixel electrodes electrically connected to the wiring via a switching element,
Each of the wirings has a lead wiring portion extending outside the display area, and each of the lead wiring portions has a first wiring and a second wiring stacked via an insulating film.
At least two conductive portions that are formed in a layered structure and electrically connect the first wiring and the second wiring to each other at at least two places, and are provided between the conductive portions; The two wirings are provided with at least two non-overlapping portions that are shifted in the surface direction of the insulating substrate.

A liquid crystal display device according to the present invention has a first insulating substrate, a plurality of wirings provided on the first insulating substrate, and a display region provided on the first insulating substrate. An array substrate having a plurality of pixel electrodes each electrically connected to the wiring via a switching element, a second insulating substrate opposed to the array substrate, and provided on the second insulating substrate. A counter electrode having a counter electrode facing the pixel electrode, and a liquid crystal composition provided between the array substrate and the counter substrate. The wiring of the array substrate is provided outside the display region. And each of the lead-out wiring portions is formed in a two-layer structure having a first wiring and a second wiring stacked via an insulating film.
At least two conductive portions that electrically connect the first wiring and the second wiring to each other at at least two places, and are provided between the conductive portions, and the first wiring and the second wiring are provided on a surface of the insulating substrate. And at least two non-overlapping portions that are shifted in the direction.

According to the wiring substrate, the array substrate, and the liquid crystal display device having the above-described structures, the wiring or the lead-out wiring portion is provided with two
With the layered structure, the connection state can be maintained even when one of the first and second wirings is disconnected, and the reliability for the disconnection is improved. Also, by providing a repair region in each wiring or a non-overlapping portion in each lead-out wiring portion, when a short-circuit failure occurs between the wirings, the first or second wiring can be easily formed in the repair region or the non-overlapping portion. It becomes possible to cut.

Further, according to a method of manufacturing an array substrate of a display device according to the present invention, a short-circuit defect between the lead-out wiring portions is detected, and when the short-circuit defect is detected, the draw-out wiring portion in which the short-circuit defect is detected. A step of cutting either one of the first wiring and the second wiring at the non-overlapping portion.

In the cutting step, one of the two adjacent lead-out wiring portions where a short-circuit defect is detected cuts the first wiring at the position of the non-overlapping portion, and the other lead-out wiring portion is connected to the non-overlapping portion. The second wiring is cut at the position of the part. In the cutting step, cutting is performed by laser irradiation.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an active matrix type liquid crystal display device according to an embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIG.
The liquid crystal display device includes a liquid crystal panel 10, a signal line driving circuit board 12 for driving the liquid crystal panel, a scanning line driving circuit board 14, and a plurality of tape carrier packages (electrically connecting each driving circuit board and the liquid crystal panel). (Referred to as TCP)
16 is provided.

As shown in FIGS. 1 and 2, the liquid crystal panel 10 includes an array substrate 18 and a counter substrate 20, and these substrates are attached at a predetermined gap by bonding their peripheral portions with a sealant described later. They are arranged facing each other. A liquid crystal composition 26 is sealed between the array substrate 18 and the counter substrate 20 via the alignment films 23 and 24, respectively. Polarizing plates 28 and 30 are disposed on the outer surfaces of the array substrate 18 and the opposing substrate 20 functioning as a wiring substrate in the present invention, respectively.

As shown in FIGS. 2 and 3, the array substrate 18 has a 0.7 mm-thick glass substrate 31 functioning as a first insulating substrate, and 800 × 3 lines are formed on this glass substrate as wiring. The signal lines 32 and the 600 scanning lines 34 are provided in a matrix at right angles to each other. The area surrounded by the signal line 32 and the scanning line 34 has an IT
A pixel electrode 36 made of O is provided, and each pixel electrode is a thin film transistor (hereinafter referred to as a TFT) as a switching element.
) Is connected to the intersection of the signal line 32 and the scanning line 34.

A substantially rectangular display area 40 is defined by a number of pixel electrodes 36. On the glass substrate 31, for example, a rectangular frame-shaped sealant application region 42 for applying a sealant made of an ultraviolet curable resin or the like is provided so as to surround the display region 40.

Each scanning line 34 is formed of a low-resistance metal material such as a molybdenum-tungsten (Mo-W) alloy, for example. Each scanning line 34 extends between two opposing short sides 31 a and 31 b of the glass substrate 31. One end of the scanning line 34 is in the sealant application region 4
2 and is drawn out to one short side 31b to form a lead-out wiring portion 48 that is electrically connected to the scanning line connection pad 47 on the glass substrate 31. And the scanning line connection pad 4
7 is connected to the scanning line driving circuit board 14 via the TCP 16.

The signal lines 32 are arranged on the scanning lines 34 via a gate insulating film 43 made of a nitride film so as to be substantially orthogonal to the scanning lines. The signal line 32 is formed of, for example, a low-resistance metal such as an aluminum (Al) alloy. Each signal line 32 extends between two opposing long sides 31 c and 31 d of the glass substrate 31.

Then, one end of each signal line 32 is drawn out to one long side 31 d beyond the sealant application area 42, and is connected to a lead-out wiring section 46 which is electrically connected to the signal line connection pad 44 on the glass substrate 31. Is composed. The signal line connection pad 44 is connected to the signal line drive circuit board 12 via the TCP 16.

As can be clearly understood from FIG.
The semiconductor layer 52 made of an a-Si: H film is formed on the gate electrode using the scanning line 34 itself as a gate electrode 50 with a gate insulating film 43 interposed therebetween. On the semiconductor layer 52, silicon nitride is disposed as a channel protective film 53 which is self-aligned with the scanning line.

The semiconductor layer 52 has a source electrode 54
And is electrically connected to the signal line 32 via the drain electrode 55. Note that the semiconductor layer 52 may be made of polysilicon (p-Si), a compound semiconductor, or the like.

According to the array substrate 18 of the liquid crystal display device according to the present embodiment, the lead wiring portion 4 of each signal line 32 is provided.
6 and the lead-out wiring portion 48 of each scanning line 34 are formed in a two-layer wiring structure. 5 (a), (b),
(C) is a cross-sectional view taken along lines AA, BB, and CC in FIG. 4.

That is, the lead wiring portion 4 of the signal line 32
6 will be described. As shown in FIGS. 4 and 5,
The lead-out wiring part 46 is composed of a first wiring 46 a made of a Mo—W alloy formed on the glass substrate 31 and an Al formed on the first wiring 46 a with the gate insulating layer 43 interposed therebetween.
And a second wiring 46b made of an alloy.

The first and second wirings 46a and 46b have contact through holes 64 as conduction parts at two places on the display area 40 side and the signal line connection pad 44 side with the sealant application area 42 interposed therebetween. Through each other.

Further, the lead-out wiring portion 46 is located at two positions on the display region 40 side and the signal line connection pad 44 side with the sealant application region 42 interposed therebetween, and between the two contact through holes 64. It has a non-overlapping portion 66. In each non-overlapping portion 66 functioning as a repair region, one of the first and second wirings 46a and 46b, for example, the second wiring 46b is shifted from the first wiring 46a in the surface direction of the glass substrate 31. Detour route section 46
c.

As in the case of the array substrate 18 having the above-described structure, the lead-out wiring portion 46 of the signal line 32 has a two-layer wiring structure, so that the first wiring 46a or the second wiring 46b may be Even if one of them breaks, the other wiring is maintained in a connected state,
There is no disconnection failure. Therefore, it is possible to improve the reliability with respect to the open wiring.

The space between the lead wiring portions 46 is about 10 to 20 μm at the minimum portion.
It is very narrow as compared with the inter-wiring space of 50 to 100 μm. Therefore, there is a high possibility that a short circuit occurs between the lead wiring portions 46.

Therefore, as shown in FIG. 6A, for example, when a short circuit occurs between the first wirings 46a in two adjacent lead-out wiring portions 46 of the signal line 32, one of the lead-out wiring portions 46 In the two non-overlapping portions 66, the X and X 'portions of the first wiring 46a are cut by, for example, laser irradiation. Thus, short circuit between the first wirings 46a can be avoided.

Further, as shown in FIG.
When a short circuit occurs between the second wirings 46b in one of the lead wiring portions 46, the Y and Y 'portions of the second wiring 46b are connected to the non-overlapping portions 66 of one of the lead wiring portions 46 by, for example, a laser. Cut by irradiation. Thus, short circuit between the second wirings 46b can be avoided.

Here, in the case of the two-layer wiring structure, it is difficult to cut only one of the wirings at the cut portion.
According to the lead-out wiring portion 46 having the above configuration, since the first and second wirings 46a and 46b have the non-overlapping portions 66 which are provided so as to be shifted in the surface direction of the glass substrate, the non-overlapping portions are Only one wiring can be easily cut.

The detection of the short circuit between the wirings is performed by bringing an inspection probe into contact with the signal line connection pad 44 and the scanning line connection pad 47 in the final stage of the array substrate manufacturing process, and measuring the electrical characteristics. In this case, it is possible to specify which of the lead-out wiring portions has a short-circuit failure, but it is difficult to determine whether the short-circuit failure is between the first wiring or the second wiring. is there.

However, if a short circuit between the lead-out wiring portions 46 is detected, if the cutting positions X, X 'and Y, Y' described above are cut at the same time, the first short-circuit defect occurs.
In both the case of the wirings 46a and the case of the second wirings 46b, the short circuit between the lead-out wiring portions can be repaired, and other defects such as the opening of the wiring do not occur. Therefore, according to the present embodiment, when the lead-out wiring portion in which the short-circuit defect has occurred is specified in the inspection process, as shown in FIG. 4, both the lead-out wiring portions are unconditionally cut at the cutting positions X, X ',
And Y, Y '.

As shown in FIG. 4, in the cutting step, the cutting positions of the respective wirings are set such that the cutting positions X and Y and the cutting positions Y and Y 'are adjacent to each other. It is desirable to select such that no other wiring exists. When the cutting positions are determined in this manner, the cutting positions X and X ′ can be continuously cut by one laser irradiation, and similarly, the cutting positions Y and Y ′ can be continuously cut by one laser irradiation. Can be cut into

Note that the lead-out wiring portion 48 of the scanning line 34 is also configured in the same manner as the lead-out wiring portion 46 of the signal line 32, and even if a short circuit occurs between the lead-out wiring portions 48, repair is performed in the same process as described above. .

On the other hand, as shown in FIG. 2, the counter substrate 20 includes a transparent glass substrate 56 functioning as a second insulating substrate, and a light shielding layer 58 made of a chromium (Cr) oxide film is provided on the glass substrate. Are formed. The light-shielding layer 58 includes the TFT 38 on the array substrate 18, the signal line 32 and the pixel electrode 3.
6 and the gap between the scanning line 34 and the pixel electrode 36 are formed in a matrix so as to shield the gap from each other.

On the glass substrate 56, a red color is placed at a position facing the pixel electrode 36 on the array substrate 18 side.
Green and blue color filter layers 60 are formed. A transparent counter electrode 61 made of ITO and an alignment layer 24 are sequentially provided on the light-shielding layer 58 and the color filter layer 60.

After the inspection and repair of the array substrate 18 are completed, a sealant is applied to the sealant application region 42 of the array substrate 18 and the peripheral portions of the array substrate 18 and the counter substrate 20 are bonded together. The liquid crystal panel 10 is manufactured by enclosing the liquid crystal composition 26 therebetween.

According to the liquid crystal display device configured as described above, the extraction wiring section 4 for the signal lines 32 and the scanning lines 34 is provided.
By forming the wirings 6 and 48 with a two-layer wiring structure, the rate of occurrence of disconnection failure can be reduced, and the reliability of wiring open can be improved. Further, each lead-out wiring portion is provided in the non-overlapping area 66.
Is provided, it is possible to easily repair a short-circuit failure even when a short-circuit occurs between the lead wirings.

Further, the non-overlapping portion 66 of each lead-out wiring portion
Are located on both sides of the sealant application region 40 and have a two-layer wiring structure on the sealant application region. Therefore, for example, an ultraviolet-curing type sealing agent is applied to the sealing agent application region 40, and the lead wiring portions 46, 4.
In the case of irradiating ultraviolet rays through 8, the generation of the unirradiated area of the sealant due to the lead-out wiring portion can be reduced, and the reduction of the sealing strength and the displacement of the array substrate and the counter substrate can be avoided.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, the wiring substrate according to the present invention is not limited to the array substrate of the liquid crystal display device described above, but may be any substrate provided with a large number of wirings on an insulating substrate, such as a printed wiring board used in electronic equipment. Can also be applied. Also in this case, by providing the wiring provided on the insulating substrate in a two-layer structure and providing at least two conductive portions and at least two repair regions, the same operation and effect as in the above-described embodiment can be obtained. Can be.

[0044]

As described in detail above, according to the present invention, the occurrence of disconnection failure is reduced, and a short-circuit failure between wirings is easily repaired. An array substrate capable of manufacturing a high-quality liquid crystal display device at low cost and high yield, a liquid crystal display device including the array substrate, and a method of manufacturing a wiring substrate and an array substrate can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an active matrix type liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a liquid crystal panel in the liquid crystal display device.

FIG. 3 is a perspective view schematically showing an array substrate of the liquid crystal panel.

FIG. 4 is a plan view schematically showing a lead wiring section of the array substrate.

FIG. 5 is a sectional view taken along lines AA, BB, and CC in FIG. 4;

FIG. 6 is a plan view of a lead-out wiring section schematically showing a cutting position where a short-circuit between lead-out wirings has occurred.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Liquid crystal panel 18 ... Array substrate 20 ... Opposite substrate 31 ... Glass substrate 32 ... Signal line 34 ... Scanning line 36 ... Pixel electrode 38 ... TFT 40 ... Display area 42 ... Sealant application area 44 ... Signal line connection pads 46 and 48 ... Lead-out wiring 47... Scanning line connection pad 46a... First wiring 46b... Second wiring 46c .. detour path part 64... Contact through hole 66...

Claims (11)

(57) [Claims] An insulating substrate, and a plurality of wirings provided on the insulating substrate, wherein each of the wirings is formed by a first wiring and a second wiring stacked via an insulating film. And at least two conductive portions that electrically connect the first wiring and the second wiring to each other at at least two places, and are provided between the conductive portions, and the first wiring and the second wiring are insulated from each other. A wiring board, comprising: at least two repair regions that are shifted from each other in a plane direction of the board. 2. An insulating substrate, comprising: a plurality of wirings provided on the insulating substrate, wherein each of the wirings is formed by a first wiring and a second wiring stacked via an insulating film. And at least two conductive portions that electrically connect the first wiring and the second wiring to each other at at least two places, and are provided between the conductive portions, and the first wiring and the second wiring are insulated from each other. In a method of manufacturing a wiring board having at least two repair regions that are displaced in a plane direction of a substrate, a short circuit between the wirings is detected, and when the short circuit is detected, the short circuit is detected. A method of cutting either one of the first wiring and the second wiring in the repair region of the formed wiring. 3. In the cutting step, one of two adjacent wirings for which a short-circuit defect has been detected cuts a first wiring at a position of the repair region, and the other wiring is cut at a position of the repair region. The method according to claim 2, wherein the second wiring is cut. 4. An insulating substrate, a plurality of wirings provided on the insulating substrate, and a display area provided on the insulating substrate, each of which is electrically connected to the wiring via a switching element. A plurality of pixel electrodes connected to each other, wherein the wiring has a lead wiring portion extending outside the display region, and the lead wiring portions are stacked via an insulating film. At least two conductive portions, which are formed in a two-layer structure having one wiring and a second wiring, and electrically connect the first wiring and the second wiring to each other at at least two places; An array substrate for a display device, comprising: at least two non-overlapping portions provided so that the first wiring and the second wiring are shifted from each other in a surface direction of the insulating substrate. 5. The insulating substrate has a sealant application region provided so as to surround the display region, and the at least two conductive portions of each of the lead-out wiring portions have the sealant application region therebetween. The at least two non-overlapping portions are located on both sides of the sealant application region with the sealant application region interposed therebetween. An array substrate of the display device according to 1. 6. An insulating substrate, a plurality of wirings provided on the insulating substrate, and a display area provided on the insulating substrate, and each of the wirings is electrically connected to the wiring via a switching element. A plurality of connected pixel electrodes, wherein the wiring has a lead-out wiring portion extending outside the display area, and each of the lead-out wiring portions,
It is formed in a two-layer structure having a first wiring and a second wiring stacked via an insulating film, and has at least two layers.
At least two conductive portions electrically connecting the first wiring and the second wiring to each other at two places, and provided between the conductive portions, wherein the first wiring and the second wiring are arranged in a plane direction of the insulating substrate; In a method for manufacturing an array substrate of a display device having at least two non-overlapping portions shifted from each other, a short-circuit defect between the lead-out wiring portions is detected, and when the short-circuit defect is detected, the short-circuit defect is detected. A method of cutting either one of the first wiring and the second wiring at the non-overlapping part of the lead-out wiring part in which is detected. 7. In the cutting step, one of two adjacent lead-out wiring portions where a short-circuit defect is detected cuts the first wiring at the position of the non-overlapping portion, and the other lead-out wiring portion is 7. The method according to claim 6, wherein the second wiring is cut at the position of the non-overlapping portion. 8. In the cutting step, when each of two adjacent lead-out wiring portions where a short-circuit defect is detected is cut at the position of the non-overlapping portion, the first wiring of one of the lead-out wiring portions and 7. The method of manufacturing an array substrate for a display device according to claim 6, wherein the one wiring is continuously cut off from the second wiring of the other lead-out wiring portion adjacent to the other wiring without passing through another wiring. 9. The method according to claim 6, wherein the cutting is performed by laser irradiation. 10. A first insulating substrate, a plurality of wirings provided on the first insulating substrate, and a display area provided on the first insulating substrate, each being formed via a switching element. An array substrate having a plurality of pixel electrodes electrically connected to the wiring, a second insulating substrate disposed to face the array substrate, and facing the pixel electrode provided on the second insulating substrate; A counter substrate having a counter electrode; and a liquid crystal composition provided between the array substrate and the counter substrate. The wiring of the array substrate is a lead-out wiring extending outside the display area. Each of the lead-out wiring portions is formed in a two-layer structure having a first wiring and a second wiring stacked with an insulating film interposed therebetween, and the first wiring and the first wiring are formed in at least two places. With two wires At least two non-overlapping portions provided between the conducting portions, wherein the first wiring and the second wiring are shifted from each other in a surface direction of the insulating substrate; A liquid crystal display device comprising: 11. A first insulating substrate, a plurality of signal lines and scanning lines provided in a matrix on the first insulating substrate, and surrounded by the signal lines and scanning lines on the first insulating substrate. A plurality of pixel electrodes provided in the respective areas and electrically connected to the signal lines and the scanning lines via the switching elements to form a display area,
A counter substrate including: an array substrate having: a second insulating substrate disposed to face the array substrate; a counter electrode provided on the second insulating substrate and facing the pixel electrode; A liquid crystal composition provided between the substrate and the substrate, wherein the array substrate and the counter substrate are attached to each other with a sealant applied so as to surround the display region, and a signal line and a scan line of the array substrate are provided. Each has a lead-out wiring portion extending to the outside of the display region through the application region of the sealant, and at least each of the lead-out wiring portions of the signal line is provided with a first layer laminated via an insulating film. The first wiring and the second wiring are electrically connected to each other at at least two places that are not overlapped with the sealant application region and are formed in a two-layer structure having a wiring and a second wiring. At least two conductive portions that have been passed, and a portion between the conductive portions that is not overlapped with the application region of the sealant, wherein the first wiring and the second wiring are shifted from each other in a surface direction of the insulating substrate. A liquid crystal display device comprising at least two non-overlapping portions.