JP2002107749A - Liquid crystal display device and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a picture excellent in display quality by controlling occurrence of reverse light leakage in the case of V-column reverse driving of a liquid crystal display device of which the organic resinous color layer is formed under pixel electrodes. SOLUTION: In the liquid crystal display device wherein pixel electrodes are arranged at crossing parts of signal lines and scanning lines in a matrix form via TFTs to form a pixel area, one side end pat of each pixel electrode is bent and structured into a bent-up form. When a pixel electrode of such a structure is V-column reverse driven, an electric field between adjacent pixel electrodes is decreased in the lateral component, and liquid crystal molecules are less disturbed in alignment by a lateral tension. Thus, the reverse light leakage is controlled, and it is possible to display a picture improved in contrast and excellent in display quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thin film transistor (TFT) type liquid crystal display device and a method of manufacturing the same.
In particular, the present invention relates to a structure of a pixel electrode in a pixel region for displaying an image.

[0002]

2. Description of the Related Art Conventionally, in a liquid crystal display device, particularly a liquid crystal display device using a thin film transistor (TFT), a pixel electrode is arranged at an intersection of a signal line and a scanning line via a TFT to form a pixel region. I have. In order to increase the aperture ratio of the pixels and obtain a bright liquid crystal panel, the openings on the glass substrate and the source electrode are covered with an organic resin-based coloring layer (interlayer insulating film) and flattened. The structure to arrange is adopted.

FIG. 4 is a schematic plan view showing a conventional arrangement of pixel regions. In the pixel region 31, the pixel electrodes 32 are arranged in a matrix. These pixel electrodes 32 have V
When the column inversion driving is performed, the pixel electrode 32 adjacent in the vertical direction is used.
Are alternately inverted for each frame.

[0004]

In the above-described V column inversion driving method, since the polarity of the adjacent pixel electrodes is inverted, a horizontal electric field is applied between the adjacent pixel electrodes 32 as shown in FIG. Occurs, and the alignment of the liquid crystal molecules at the edge of the pixel electrode is disturbed.
FIG. 6 is an explanatory diagram showing a horizontal electric field generated between pixel electrodes and a state of light leakage (hereinafter, referred to as “reverse”) in a misalignment region generated by the electric field. As shown in the lower part of the figure, since a horizontal electric field is generated between the pixel electrodes 32,
As shown in the upper part of the figure, it is shown that reverse light leakage a has occurred. In the figure, reference numeral 33 denotes a signal line.

Therefore, when the V-column inversion drive is performed in the liquid crystal display device having the conventional structure, there is a problem that the light leaks to lower the contrast and deteriorate the display quality.

An object of the present invention is to provide a liquid crystal display device capable of suppressing reverse light leakage and obtaining an image with excellent display quality, and a method of manufacturing the same.

[0007]

According to a first aspect of the present invention, there is provided a liquid crystal display device in which a plurality of pixel electrodes arranged in a matrix form a pixel region. Is characterized in that the end of one side has a bent structure.

A second aspect of the present invention is characterized in that, in the first aspect, the pixel region is driven by V column inversion.

According to another aspect of the present invention, a pixel electrode connected via a thin film transistor to an intersection of a signal line and a scanning line arranged in a grid is arranged in a matrix. In the method of manufacturing a liquid crystal display device in which a pixel region is formed, when the colored organic resin is patterned in a stripe shape, one end of the colored layer is first patterned in a stripe shape. Patterning a part of the coloring layer so as to overlap from above, and forming a pixel on the plurality of coloring layers patterned as described above such that one side on the reverse side reaches the upper part of the overlapping part of the coloring layer. Forming an electrode.

A fourth aspect of the present invention is characterized in that, in the third aspect, the coloring layer is a transparent organic film.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a liquid crystal display according to the present invention will be described below with reference to the drawings. FIG.
FIG. 1 is a schematic cross-sectional view illustrating a structure of a pixel region of a liquid crystal display device according to the present embodiment, and particularly illustrates a structure of a pixel electrode. The end b of one side of the pixel electrode 12 has a structure in which it is bent upward and jumps up with respect to an array substrate (located below the pixel electrode 12) (not shown). The side that jumps up the end of the pixel electrode 12 is the side on the reverse side where light leakage occurs.

FIG. 2 is an explanatory view showing an electric field generated between the pixel electrodes when the V-column inversion driving is performed using the pixel electrode 12 having the above-described structure, and a state of reverse light leakage.
In the figure, the electric field generated between the pixel electrodes shown in the lower part is slightly higher than the conventional one, and the horizontal component is reduced. This weakens the degree to which the liquid crystal molecules at the edge of the pixel electrode are laterally pulled and the alignment is disturbed. Therefore, in the figure, a
As shown in the figure, it can be seen that the adoption of the pixel electrode structure of this example suppresses light leakage more than before.
In the figure, reference numeral 6 denotes a signal line.

According to the present embodiment, by forming a structure in which the edge of one side of the pixel electrode 12 arranged in the pixel region is bent and jumped up, reverse light leakage is suppressed.
The display quality can be improved by increasing the contrast.

FIG. 3 is a schematic cross-sectional view for explaining a manufacturing process of the liquid crystal display device according to the present embodiment configured as described above. Here, in particular, a cross section of an array substrate on which pixel electrodes and the like are formed is shown.

First, a 500 nm SiOx film 1 is formed on a glass substrate (array substrate) 50 by a CVD method.
This layer is used as a blocking layer for impurities from the glass substrate 50 and a semiconductor layer of the thin film transistor is formed thereon.
-Si (amorphous silicon) 500 ° plasma C
Film formation by VD method, excimer laser annealing (EL
A) is performed to form a p-Si (polycrystalline silicon) layer 2. A resist is applied on the p-Si layer 2, and the resist is patterned by using a mask, and then processed by dry etching.

Thereafter, a SiOx film 3 is used as a gate insulating film.
Is formed to a thickness of 1000 ° by the CVD method. Next, P (phosphorus) ion implantation is performed by a normal source and drain formation method,
Form source and drain. After that, a molybdenum tungsten alloy (MoW) is formed into a film, which is processed by dry etching to form the gate electrode 4. Next, SiOx is deposited as the interlayer insulating film 5 by the CVD method.
Å Form. After that, the source and drain are activated using ELA. Subsequently, a mask is patterned into a shape of a contact hole by using a photoresist, and a hole is formed by dry etching.

After that, a signal line 6 and a source electrode 7 whose ends also serve as a drain electrode are formed by sputtering and patterned.

Further, a SiNx film 8 is formed thereon as a protective film.
Is formed by plasma CVD, and the opening of the pad portion is formed. After that, the unevenness is further flattened, and a colored layer 9 made of an organic resin colored red having the function of a color filter is applied at 2 μm. A hole is formed in the same place as the SiNx layer and patterned in a stripe shape.

Thereafter, similarly, a blue colored organic resin 10 is applied in a thickness of 2 μm and then patterned in a stripe shape. At this time, the adjustment is performed so that the end of the blue layer overlaps the end of the red layer patterned in a stripe shape by about 3 μm. Subsequently, a green layer 11 is applied to a thickness of 2 μm, and the stripe edge is applied to both the red layer and the blue layer by 3 μm.
Patterning is performed so that m overlaps.

Finally, when the pixel electrode 12 is formed such that its reverse side end is on the above-mentioned colored layer overlapping portion (bank-like portion), one end of the side as shown in FIG. 1 is bent and jumps up. The pixel electrode 12 can be easily formed, and the array substrate side is completed.

When a liquid crystal display device was prepared using this array substrate by an ordinary method, reverse light leakage was suppressed, and an image having high contrast and excellent display quality could be obtained.

In the above embodiment, the bank is formed by overlapping the colored layers. However, even if the same stripe patterning is performed using a transparent organic film, the bank is formed by the transparent organic film. By patterning the pixel electrode in the same manner as above, a pixel electrode having the structure shown in FIG. 1 can be obtained. Even when a liquid crystal display device is formed using the array substrate formed by this method, a high-quality image with little light leakage, which is the same as the above embodiment, can be obtained.

[0023]

As described above in detail, according to the liquid crystal display device of the present invention, the horizontal component of the electric field generated between the vertically adjacent pixel electrodes can be reduced.
An image with excellent display quality can be obtained by suppressing the occurrence of reverse light leakage.

According to the method of manufacturing a liquid crystal display device,
A structure in which the end of the pixel electrode is bent and jumped up can be easily provided.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating a structure of a pixel region of a liquid crystal display device according to an embodiment.

FIG. 2 is an explanatory diagram showing an electric field generated between pixel electrodes and light leakage when V column inversion driving is performed using the pixel electrode having the structure shown in FIG. 1;

FIG. 3 is a schematic cross-sectional view for explaining a manufacturing process of the liquid crystal display device according to the embodiment.

FIG. 4 is a schematic plan view showing a pixel region of a conventional liquid crystal display device.

FIG. 5 is a schematic side view showing a side surface of the pixel electrode shown in FIG. 4;

FIG. 6 is an explanatory diagram showing a state of a horizontal electric field and light leakage generated between the pixel electrodes shown in FIG. 5;

[Explanation of symbols]

1,3: SiOx film, 2: p-Si (polycrystalline silicon)
Layer, 4 gate electrode, 5 interlayer insulating film, 6 signal line, 7
... Source electrode, 8 ... SiNx film, 9 ... Colored layer, 10 ... Organic resin, 11 ... Green layer, 12 ... Pixel electrode 50 Glass substrate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H091 FA02Y FB02 FC12 FD04 GA03 GA07 GA13 GA16 LA03 LA15 LA17 2H092 GA13 GA21 HA03 HA28 JA24 JA35 JB57 JB58 KA04 KA05 KA10 KA12 KA19 KB24 KB25 MA07 MA27 MA30 NA01 PA08 2H09 NA16 5C094 AA02 AA06 AA43 BA03 BA43 CA19 EA04 EA05 EB02 HA08

Claims (4)

[Claims] 1. A liquid crystal display device in which a pixel region is formed by a plurality of pixel electrodes arranged in a matrix, wherein an edge of one side of each of the pixel electrodes has a bent structure. . 2. The liquid crystal display device according to claim 1, wherein the pixel region is driven by V column inversion. 3. A method for manufacturing a liquid crystal display device, wherein pixel electrodes connected via a thin film transistor at intersections of signal lines and scanning lines arranged in a lattice are arranged in a matrix to form a pixel region. When patterning the colored organic resin in a stripe pattern, a step of patterning such that one end of the colored layer overlaps a part of another colored layer previously patterned in a stripe form from above. And, on the plurality of colored layers patterned as described above,
Forming a pixel electrode such that one side reaches an upper part of the overlapping portion of the colored layer. A method for manufacturing a liquid crystal display device, comprising: 4. The method according to claim 3, wherein the colored layer is a transparent organic film.