JP2812346B2 - Liquid crystal display device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix liquid crystal display device, and more particularly to a structure of a wiring portion around a display area in an active matrix array substrate.

[0002]

2. Description of the Related Art In recent years, an active matrix liquid crystal panel comprising a display element array having switching elements formed on the surface of a large substrate such as glass has been put into practical use.
It has been spotlighted as a thin and lightweight display device replacing T.

[0003] The active matrix liquid crystal display device includes an active matrix array substrate, including, become more display cell and switching the active elements and the liquid crystal drive transparent electrodes arranged in a matrix, and a plurality of gate wirings connecting them In addition, a plurality of signal wirings orthogonal to the gate wiring via the insulating film are mounted. Such an active matrix array substrate is formed by sequentially repeating deposition and patterning of a semiconductor thin film, an insulating thin film, and a conductive thin film on one entire surface of a glass substrate.

[0004]

In such a structure of a wiring portion of a conventional active matrix array substrate, for example, a glass substrate and a metal thin film forming wiring, or a metal wiring and an insulating film covering the same, are formed. Some of the constituent atoms of the wiring metal move due to the difference in the thermal expansion coefficient and the internal stress of the metal film. Such a phenomenon is called stress migration in this technical field. This stress migration may cause disconnection of the wiring. In addition, there is also a disconnection of the wiring due to the introduction of a defect in the wiring pattern forming step or the poor step coverage of the metal film in the step structure. The broken wiring eventually appears as a linear display defect and becomes defective. The probability of occurrence of such a defect increases as the area of the display screen increases and the length of the wiring increases. As a result, the yield is reduced, which is a major problem from the viewpoint of productivity.

An inspection step for determining the presence or absence of a display defect is difficult during the active matrix array substrate forming step. Usually, the inspection step is performed by overlapping the counter substrate (a color filter substrate in a color display liquid crystal) between the two substrates. This is performed after the panel forming step of enclosing the liquid crystal in the panel. In other words, the inspection is performed after the added value has been increased. For example, even if a panel having the above-mentioned linear display defect is found, the panel is discarded at that point, resulting in a large loss. Therefore, a wiring structure has been proposed in which an auxiliary wiring for repair and a connection terminal to the outside thereof are provided in a peripheral area outside the display section on the active matrix array substrate (for example, US Pat. No. 4,688, 896 and U.S. Pat. No. 4,840,459).

In the example of the United States patent, a repair auxiliary wiring orthogonal to the gate wiring or the wiring extension part outside the display area on the side opposite to the input terminal of the drive electric signal of the signal wiring and the outside thereof is provided. And a connection terminal. If a break occurs in the gate wiring or the signal wiring, the intersection with the auxiliary wiring is short-circuited on the open end side of the wiring, and the broken wiring drive electric signal is simultaneously supplied from the external connection terminal of the auxiliary wiring to cause a display defect. It will be repaired.

However, in the example of the US patent, a drive signal for a broken wire generated at an unspecified location for each defective panel is selected from a group of hundreds, and sometimes thousands, of wires. Then, it is once taken out of the panel, bypassed, and supplied again from the external connection terminal of the auxiliary wiring. Therefore, the terminal group having a fine pitch of 100 to 200 μm on the substrate side on which the drive circuit LSI is mounted and the wiring input terminal group on the active matrix array substrate side are aligned, and several tens to hundreds or more are simultaneously packaged. It is practically impossible to extract a specific drive signal arbitrarily, bypass it, and supply it to the external connection terminal of the auxiliary wiring in the modularization process of overlapping and connecting, and it is practically impossible to apply it to mass production It is.

Accordingly, an object of the present invention is to provide an active matrix liquid crystal display device having a wiring structure capable of avoiding the problem of the above-mentioned conventional method of repairing a disconnection of a wiring portion of an active matrix array substrate.

[0009]

According to the present invention, there is provided a liquid crystal display device comprising: a first wiring group extending in parallel on an active matrix array substrate; an interlayer insulating film covering the entire surface of the substrate; A second wiring group extending in parallel with a direction orthogonal to the first wiring group on the film.

According to the invention, one or both of the first wiring group and the second wiring group on the input terminal side and the open end side extending portion outside the display region and outside the counter substrate frame and the insulating film comprising at least one or more auxiliary wires for repairing orthogonal in a form insulated through said first distribution
It with the lines or the second wiring group of the input terminal side and the open end extending portion of the wire near the intersection of the auxiliary line
For short-circuit protruding in a direction different from the direction in which each wiring extends
Wiring pattern and insulating film on the lower layer short-circuit wiring pattern
And a liquid crystal display device having the opening provided .

Further , according to the present invention, there is provided a method for local chemical vapor deposition.
Metal film deposition on active matrix substrate
At the protruding part near any intersection between the wiring and the auxiliary wiring
Liquid crystal display device characterized in that both are electrically short-circuited by
A method of manufacturing the device is obtained.

[0012]

Next, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1 FIG. 1 is a plan view of a wiring portion of an active matrix array substrate constituting an active matrix liquid crystal display device according to a first embodiment of the present invention.

In the illustrated active matrix array substrate, a first wiring 102 serving as a gate wiring of a switching transistor (not shown) is formed on a surface of a glass substrate, and an interlayer insulating film (see FIG. 1) covering the entire substrate including the first wiring 102 is provided. (Not shown), and a second wiring 105 which is orthogonal to the first wiring 102 and serves as a signal wiring is formed. First wiring 102
A display cell composed of a switching transistor and a pixel transparent electrode (not shown) is disposed at the intersection of each of the first and second wirings 105. The auxiliary wiring 107 is formed on the active matrix array substrate corresponding to the outside of the outer shape 106 of the counter substrate. Further, at both ends of the first wiring where the disconnection 108 has occurred, the first wiring and the auxiliary wiring are short-circuited 109 at two points crossing the auxiliary wiring.

The time constant (propagation delay time) of a wiring repaired by disconnection by the auxiliary wiring is always larger than that of a normal wiring without disconnection. Further, a drive circuit (not shown) that drives each wiring cannot distinguish between a normal wiring and a wiring whose wiring has been repaired. Therefore, in order to reduce the resistance value of the resistance of the auxiliary wiring portion and the capacitance value of the capacitance, it is necessary to select a material having a low resistivity for the auxiliary wiring portion and perform an optimal design of the pattern arrangement. Further, it is desirable that the driving capability of the driving circuit has a sufficient margin.

The number of auxiliary wirings is related to the appearance rate of the number of disconnected wires to be relieved at the production stage, the cost of the repair process, the area of the peripheral area required for the auxiliary wirings, and the like.

Various methods are conceivable for short-circuiting the auxiliary wiring and the disconnected wiring. As one of the methods, for example, there is a method in which an intersection of an auxiliary wiring and a disconnected wiring is irradiated with laser light to break an interlayer insulating film. This method is called a laser irradiation method. As another method, FIG.
There is also a method shown in

Referring to FIG. 3, a pattern dedicated to short-circuiting is provided near the intersection of the auxiliary wiring 307 and the wiring 302.
(To be described later) and an insulating film opening 304 are provided in advance. That is, the auxiliary wiring 30 is provided as a short-circuit-only pattern.
7 protruding in a direction different from the direction in which it extends
11 and a direction different from the direction in which the wiring 302 extends.
A protruding projection 312 is provided in advance. Then, the portion required for short-circuiting is deposited on the metal deposited thin film 31 by local chemical vapor deposition.
The auxiliary wiring 307 and the wiring 302 by 0, projections 3
11, the projection 312, and the projection 312
Short circuit through the insulating film opening 304 . This method is called a short circuit method. In this short-circuit method, the possibility of damaging the wiring due to the auxiliary wiring or disconnection is extremely small as compared with the laser irradiation method.

Embodiment 2 FIG. 2 is a plan view of a wiring portion of an active matrix array substrate constituting an active matrix liquid crystal display device according to a second embodiment of the present invention.

[0020] In the first embodiment described above, the auxiliary wiring has been around the display region periphery, the distinction between a for the first wiring and the second wiring was not. On the other hand, in the second embodiment, the auxiliary wiring is arranged so as to extend around the outer periphery of the display area by half, and the auxiliary wiring 207a for the first wiring and the auxiliary wiring 2 for the second wiring are arranged.
07b. In the structure of the second embodiment, the area of the peripheral region required for one auxiliary wiring is as follows.
Only half that of the first embodiment is required.

[0021]

As described above, according to the present invention,
The linear display defect can be repaired only by short-circuiting two places at both ends of the disconnected wiring to the auxiliary wiring. The display defect can be repaired not only after the panel is formed but also when a driving circuit board is attached to the periphery. Furthermore, since there is no need to extract a specific drive signal according to the disconnection position, bypass it, and supply it separately to the external connection terminal of the auxiliary wiring, there is no need for any special additional processes such as inspection and repair processes in the modularization process do not do.

As a result, an active matrix liquid crystal display device can be manufactured at low cost and with high yield.

[Brief description of the drawings]

FIG. 1 is a plan view of a wiring portion of an active matrix array substrate constituting an active matrix liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a plan view of a wiring portion of an active matrix array substrate constituting an active matrix liquid crystal display device according to a second embodiment of the present invention.

3A and 3B are views for explaining a method of short-circuiting the active matrix array substrate according to the present invention, wherein FIG. 3A is a plan view and FIG.
FIG. 3 is a sectional view taken along line aa ′ of FIG.

[Explanation of symbols]

102 first wiring 105 and the second wiring 106 opposing board outline 107 auxiliary wiring 108 disconnecting section 109 short-circuit point 202 first wiring 205 second wiring 206 opposing board outline 207a, 2 07b auxiliary wiring 208 disconnecting section 209 short-circuit point 301 a glass substrate 303 layers Insulating film 304 Insulating film opening 310 Deposited thin films 311 and 312 Projection

Claims (2)

(57) [Claims] 1. An active matrix array substrate comprising:
A first wiring group extending in parallel, an interlayer insulating film covering the entire surface of the substrate, and a second wiring group extending on the insulating film in parallel with a direction orthogonal to the first wiring group If, insulated through the first one or the insulating film thereof and the input terminal side and the open end extending portion of both of the second wiring group and the wiring group in Table示領outside and a counter substrate outside the frame It is provided at least one or more auxiliary wires for repairing orthogonal form
Intersection of the active matrix liquid crystal display device, and the first wiring group or the second wiring group of the input terminal side and the open end extending portion of the wiring and the auxiliary wiring that
In the direction different from the direction in which each wiring extends
The short-circuit wiring pattern and the lower-layer short-circuit wiring pattern
A liquid crystal display device comprising: an opening provided in the upper insulating film . 2. The method according to claim 1, wherein the metal film is deposited by local chemical vapor deposition.
Between the wiring on the active matrix substrate and the auxiliary wiring.
Both are electrically shorted at the protrusion near any intersection
A method of manufacturing a liquid crystal display device.