JP2003195338A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device capable of preventing static electricity from being generated and capable of preventing a luminescent point and a bright-line from being generated. <P>SOLUTION: On the TFT (thin film transistor) array substrate of a liquid crystal display device, a plurality of gate wirings 2a which extend from a packaging terminal part to the gate-terminal side through a display area are provided. Adjacent gate wirings 2a with each other are connected by a semiconductor layer 15 respectively at the packaging terminal part and at the gate-terminal side. As a result, even when static electricity is generated at one of gate wiring 2a, this static electricity is dispersed to many other gate wirings 2a with these semiconductor layers 15. Thus, generation of insulation failure or damage of TFTs or the like by the static electricity is prevented and the luminescent point and the bright-line are prevented from being generated in the liquid crystal display device. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal which drives a liquid crystal by using a TFT array substrate having a plurality of thin film transistors arranged near each intersection of a plurality of gate wirings and a plurality of source wirings. The present invention relates to a display device.

[0002]

2. Description of the Related Art In recent years, as an image display device, a TFT array substrate having a plurality of thin film transistors (hereinafter abbreviated as "TFT") formed on one main surface thereof has been used.
A transmission type liquid crystal display device in which a liquid crystal interposed between a T array substrate and a color filter substrate is driven to display an image is widely used.

An example of such a conventional liquid crystal display device will be described below with reference to FIGS. 2 (a), 2 (b) and 3. 2A and 2B are diagrams showing a pixel configuration of a liquid crystal display device of this type. Further, FIG. 3 is a diagram showing a configuration of a display area portion of a TFT array substrate of a conventional liquid crystal display device, a mounting terminal portion and a gate wiring on a gate terminal side. This conventional liquid crystal display device is manufactured by the following procedure.

First, as shown in FIGS. 2 (a) and 2 (b),
A gate electrode or gate wiring 2a and a common wiring 2b are formed on one transparent glass substrate 1a. Then 2
The gate insulating films 3 and 4 having a layered structure are deposited. Next, a semiconductor film 5 (amorphous silicon film) that causes the TFT to function as a switch while its resistance value changes depending on the applied voltage is formed. Further, an n + a-Si layer 6 (n + amorphous silicon layer) for making the semiconductor film 5 in ohmic contact with the source electrode and the drain electrode.
To form.

Then, the source electrode or source wiring 7a
And the drain electrode 7b are simultaneously formed. At this time,
At the same time, the storage capacitor C1 is formed on the common line 2b. Next, a protective film 8 is deposited to protect the TFT. Then, the transparent pixel electrode 9 is deposited. Also, the pixel electrode 9
In order to supply a signal voltage to the gate electrode, an opening is provided on the drain electrode 7b after depositing the protective film 8.

As shown in FIG. 3, in the mounting terminal portion of the liquid crystal display device, the adjacent gate wirings 2a are connected by the semiconductor layer 15. On the other hand, on the gate termination side, the adjacent gate wiring 2a is not connected. As a result, the TFT array substrate T1 forming the liquid crystal display device is completed.

On the other hand, after forming the black matrix 10 on the other transparent glass substrate 1b, red (R),
The green (G) or blue (B) color filter 11 is formed. Further, by forming the counter pixel electrode 12 thereon, the color filter substrate F1 constituting the liquid crystal display device is completed. Subsequently, a polyimide alignment film is applied to the sufficiently cleaned TFT array substrate T1 and baked. Then, this is rubbed with a cloth wound around a roller to orient the polyimide molecules in one direction. Next, an alignment film is similarly formed on the color filter substrate F1 and rubbing is performed.

After the alignment treatment, a sealing agent is applied to the TFT array substrate T1 and spacers (not shown) are scattered. Then, after pre-curing the sealant and spraying the spacers, the TFT array substrate T1 and the color filter substrate F1 are bonded together, and the sealant is completely cured. After this,
By injecting the liquid crystal 13 between both substrates in a vacuum state, sealing the both substrates with a sealant, and disposing polarizing plates (not shown) before and after the transparent glass substrates 1a and 1b, Complete.

[0009]

However, in the above conventional liquid crystal display device, a potential difference is generated between the gate wirings on the gate input side and the gate termination side, which promotes the generation of static electricity. Therefore, there is a problem that static electricity may cause insulation failure or TFT damage, which causes bright spots and bright lines in the liquid crystal display device.

The present invention has been made in order to solve the above-mentioned conventional problems, and it is possible to prevent the generation of static electricity, and to prevent defective insulation or damage to TFTs, and hence the generation of bright spots and bright lines. It is an object to be solved to provide a liquid crystal display device which can be reduced.

[0011]

A liquid crystal display device according to the present invention made to solve the above problems includes (i) a plurality of gate wirings extending from a mounting terminal portion to a gate terminal side through a display area portion; Liquid crystal driven by an array substrate having a plurality of source wirings extending in a direction intersecting with the gate wirings and thin film transistors arranged near intersections of the respective gate wirings and the respective source wirings. A display device, (ii) at the gate end side,
It is characterized in that adjacent gate wirings are connected to each other by a semiconductor layer.

In this liquid crystal display device, on the gate termination side,
Since the adjacent gate wirings are connected to each other by the semiconductor layer, even if static electricity is generated in any of the gate wirings, the static electricity is dispersed to many other gate wirings through the semiconductor layer. Therefore, the occurrence of insulation failure or TFT damage due to static electricity is prevented. Therefore, bright spots and bright lines are prevented from occurring in the liquid crystal display device.

In the above liquid crystal display device, it is preferable that adjacent gate wirings are connected by a semiconductor layer even in the mounting terminal portion. Further, it is more preferable that the semiconductor layer connecting the adjacent gate wirings has a square shape in a plan view. In this way, dispersion of static electricity generated in a certain gate wiring to other gate wiring is promoted. Therefore, it is possible to more effectively prevent the occurrence of insulation failure or TFT damage due to static electricity, and it is possible to more effectively prevent the generation of bright spots and bright lines.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below. 2 (a) and 2 (b) used in the description of the related art are basically applicable to the liquid crystal display device according to the present invention or the manufacturing method thereof, and therefore, in FIGS. 1 and 2 below. The embodiment will be described with reference to (a) and (b). FIG. 1 is a plan view showing a display area portion of a TFT array substrate of a liquid crystal display device according to an embodiment of the present invention and a structure of a gate wiring on a mounting terminal portion and a gate terminal side. The liquid crystal display device according to the present invention is manufactured by the following procedure.

That is, first, one transparent glass substrate 1
A plurality of gate electrodes or gate wirings 2a made of a conductive material (metal) such as tantalum or chromium and a plurality of common wirings 2b are formed on a. Here, each gate wiring 2a
Extends from the mounting terminal portion to the gate terminal side through the display area portion. At the same time, the storage capacitor C1 is formed on the common wiring 2b. Then, as usual,
The gate insulating films 3 and 4 having a two-layer structure are deposited by sputtering and vapor phase epitaxy. Next, a semiconductor film 5 (amorphous silicon film) that causes the TFT to function as a switch is formed while its resistance value changes depending on the applied voltage.

Further, n + a for making the semiconductor film 5 in ohmic contact with the source electrode and the drain electrode.
-The Si layer 6 is formed. Then, the source electrode or source wiring 7a made of a metal such as titanium, tantalum, molybdenum, and the drain electrode 7b are simultaneously formed. Subsequently, in order to protect the TFT, a protective film 8 made of SiNx (silicon nitride) is deposited. And ITO
A transparent pixel electrode 9 made of (indium tin oxide) is deposited. Further, in order to supply a signal voltage to the pixel electrode 9, after depositing the protective film 8, an opening is provided on the drain electrode 7b.

Then, as shown in the left side portion of FIG. 1, at the mounting terminal portion of the liquid crystal display device, adjacent gate wirings 2 are provided.
The semiconductor layers 15 (amorphous silicon layers) are connected to each other. Further, as shown on the right side of FIG. 1, even on the gate terminal side of the liquid crystal display device, adjacent gate wirings 2a are connected to each other by the semiconductor layer 15 (amorphous silicon layer). The semiconductor layer 15 preferably has a square shape in plan view. As a result, the TFT array substrate T1 forming the liquid crystal display device is substantially completed.

On the other hand, on the other transparent glass substrate 1b, after forming the black matrix 10 made of chromium or the like, the red, green or blue color filter 11 is formed. Further, by forming the counter pixel electrode 12 thereon, the color filter substrate F1 constituting the liquid crystal display device is completed. Then, a polyimide alignment film is applied to the thoroughly washed TFT array substrate T1 by a printing method,
Bake. Then, this is rubbed with a cloth wound around a roller to orient the polyimide molecules in one direction. Next, an alignment film is similarly formed on the color filter substrate F1 and rubbing is performed.

After the alignment treatment, a sealant is applied to the TFT array substrate T1 and spacers (not shown) having a constant diameter are scattered. This is to maintain a constant gap between the TFT array substrate T1 and the color filter substrate F1 when they are attached to each other. Then, after pre-curing the sealant and spraying spacers, the TFT array substrate T1 and the color filter substrate F1 are bonded together,
Completely cure the sealant. After that, the liquid crystal 13 is injected between the two substrates in a vacuum state, and the both substrates are sealed with a sealant,
Polarizing plates (not shown) before and after the transparent glass substrates 1a and 1b
The liquid crystal display device is completed by arranging.

In this liquid crystal display device, since the adjacent gate wirings 2a are connected by the semiconductor layer 15 at the mounting terminal portion and the gate termination side, respectively,
Even if static electricity is generated on any one of the gate wirings 2a, this static electricity is transmitted via the semiconductor layer 15 to a large number of other gate wirings 2a.
dispersed in a. Therefore, the occurrence of insulation failure or TFT damage due to static electricity is prevented. Therefore, bright spots and bright lines are prevented from occurring in the liquid crystal display device.

[0021]

As described above, according to the present invention, it is possible to prevent a potential difference from occurring between the gate wirings on the gate input side and the gate termination side, and to prevent the generation of static electricity. It is possible to realize a liquid crystal display device capable of preventing or reducing damage, and consequently, generation of bright spots and bright lines.

[Brief description of drawings]

FIG. 1 is a plan view showing a display area portion of a TFT array substrate of a liquid crystal display device according to an embodiment of the present invention and a configuration of a gate wiring on a mounting terminal portion and a gate terminal side.

FIG. 2A is a plan view of a display area portion of a liquid crystal display device according to the present invention or a conventional liquid crystal display device,
6B is a cross-sectional view taken along the line AB of the liquid crystal display device shown in FIG.

FIG. 3 is a plan view showing a display area portion of a TFT array substrate of a conventional liquid crystal display device and a configuration of a gate wiring on a mounting terminal portion and a gate terminal side.

[Explanation of symbols]

T1 ... TFT array substrate, F1 ... color filter substrate,
1a ... transparent glass substrate, 1b ... transparent glass substrate, 2
a ... Gate wiring (gate electrode), 2b ... Common wiring,
2c ... connection layer, 3 ... first gate insulating film, 4 ... second
Gate insulating film, 5 ... Semiconductor film (amorphous silicon), 6 ... n + a-Si layer, 7a ... Source wiring (source electrode), 7b ... Drain electrode, 8 ... Protective film,
9 ... Transparent pixel electrode, 10 ... Black matrix,
11 ... Color filter, 12 ... Opposing pixel electrode, 13
... liquid crystal, 15 ... semiconductor layer.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 29/786 H01L 29/78 612Z (72) Inventor Yoshihiro Konishi Osaka Prefecture Kadoma City 1006 Kadoma, Matsushita Electric Industrial In-house F-term (reference) 2H092 GA64 JA24 JA37 JB79 KB04 NA14 5C094 AA02 AA53 BA03 BA43 CA19 CA24 DB05 FB14 HA08 5F110 AA22 BB01 CC07 DD02 EE04 EE37 FF09 FF28 FF29 GG02 GG15 HK04 HK09 NN20 NN01 HM16 NN.

Claims (3)

[Claims] 1. A plurality of gate wirings extending from a mounting terminal portion to a gate termination side through a display area portion, a plurality of source wirings extending in a direction intersecting with the gate wirings, and each gate wiring and each source wiring. A liquid crystal display device in which liquid crystal is driven by an array substrate including a thin film transistor arranged near an intersection, and adjacent gate wirings are connected to each other by a semiconductor layer on a gate termination side. Liquid crystal display device characterized by. 2. The liquid crystal display device according to claim 1, wherein adjacent gate wirings are connected by a semiconductor layer at a mounting terminal portion. 3. The liquid crystal display device according to claim 1, wherein the semiconductor layer connecting adjacent gate lines has a square shape in a plan view.