KR102067961B1 - color filter substrate, manufacturing method thereof, and liquid crystal display device including the same - Google Patents

Abstract

The color filter substrate of the present invention comprises: a substrate in which a pixel region is defined; A color filter layer formed on the substrate, each color filter layer including red, green, and blue color filter patterns sequentially arranged in a first direction corresponding to the pixel area; And a black matrix formed on the color filter layer and exposing the color filter layer of the pixel area, wherein the red and green color filter patterns cover an edge of the blue color filter pattern.

Description

Color filter substrate, manufacturing method thereof, and liquid crystal display including the same {color filter substrate, manufacturing method, and liquid crystal display device including the same}

The present invention relates to a liquid crystal display device, and more particularly, to a color filter substrate capable of reducing external light reflection, a manufacturing method thereof, and a liquid crystal display device including the same.

Liquid crystal displays have high contrast ratios, are suitable for moving picture display, and have low power consumption, and are being used in various fields such as notebooks, monitors, and TVs. Liquid crystals have an optical anisotropy with a thin and long molecular structure and directionality in an array, and have polarization properties in which the direction of molecular arrangement changes depending on their size when placed in an electric field. Implement

In general, a liquid crystal display device arranges two substrates on which electrodes are formed so that two electrodes face each other, injects liquid crystal between the two electrodes, and then applies liquid crystal to the liquid crystal molecules by applying a voltage to the two electrodes. By moving, the device expresses the image by the transmittance of light that varies accordingly.

1 is a cross-sectional view of a conventional liquid crystal display device.

As shown in FIG. 1, the conventional liquid crystal display device includes a liquid crystal layer 70 formed between the first and second substrates 20 and 50 facing each other and the first and second substrates 20 and 50. ). Red, green, and blue pixel regions Pr, Pg, and Pb are defined on the first and second substrates 20 and 50.

The thin film transistor T and the pixel electrode 38 are formed in each pixel region Pr, Pb, and Pb of the first substrate 20.

In more detail, the gate electrode 22 is formed on the first substrate 20, and the gate insulating layer 24 is formed on the gate electrode 22.

The semiconductor layer 26 is formed on the gate insulating layer 24 corresponding to the gate electrode 22, and the source electrode 28 and the drain electrode 30 spaced apart from each other are formed on the semiconductor layer 26.

The gate electrode 22, the semiconductor layer 26, the source electrode 28, and the drain electrode 30 constitute a thin film transistor T.

The passivation layer 34 is formed on the source electrode 28 and the drain electrode 30, and the passivation layer 34 has a drain contact hole 36 exposing the drain electrode 30.

The pixel electrode 38 is formed on the passivation layer 34 to contact the drain electrode 30 through the drain contact hole 36.

The black matrix 52 is formed in the lower portion of the second substrate 50 to correspond to the thin film transistor T, and the color is formed in the lower portion of the second substrate 50 exposed by the lower portion of the black matrix 52 and the black matrix 52. Filter layer 54 is formed.

The color filter layer 54 includes red, green, and blue color filter patterns R, G, and B corresponding to the red, green, and blue pixel areas Pr, Pg, and Pb, respectively.

A transparent common electrode 56 is formed below the color filter layer 54.

The liquid crystal layer 70 is positioned between the pixel electrode 38 of the first substrate 20 and the common electrode 56 of the second substrate 50.

Polarizers (not shown) are attached to the outer surfaces of the first and second substrates 20 and 50, respectively, and light sources are disposed below the first substrate 20 to supply light, thereby allowing light from the light source to be transferred to the second substrate. Is output through 50.

However, the conventional liquid crystal display device has a disadvantage of high external light reflectance and low contrast contrast ratio. In other words, the clear room contrast ratio is determined by (maximum luminance + external light reflection luminance) / (minimum luminance + external light reflection luminance), and the reflectance of the black matrix 52 formed on the lower surface of the second substrate 50 is relatively high, so that the external light reflection is much This results in a lower contrast ratio, resulting in lower image quality.

In addition, in the case of a liquid crystal display having a high resolution, a washout phenomenon appears in the side viewing angle direction.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a color filter substrate, a method of manufacturing the same, and a liquid crystal display device including the same, which can reduce external light reflection to improve a clear room contrast ratio.

In addition, another object of the present invention is to provide a color filter substrate, a method for manufacturing the same, and a liquid crystal display device including the same, which can prevent turbidity.

In order to achieve the above object, the present invention includes a substrate having a pixel region defined; A color filter layer formed on the substrate, each color filter layer including red, green, and blue color filter patterns sequentially arranged in a first direction corresponding to the pixel area; And a black matrix formed on the color filter layer and exposing a color filter layer of the pixel area, wherein the red and green color filter patterns cover edges of the blue color filter pattern.

Each of the red, green, and blue color filter patterns extends to an adjacent pixel area in a second direction.

The edges of the red color filter pattern and the green color filter pattern overlap each other.

The blue color filter pattern includes an extension part extending along the first direction, and the extension part is covered with the red color filter pattern and the green color filter pattern.

The color filter substrate of the present invention further includes an overcoat layer covering the color filter layer and the black matrix.

In addition, the present invention comprises the steps of forming a first color filter pattern on the substrate; Forming a second color filter pattern on the substrate including the first color filter pattern; Forming a third color filter pattern on the substrate including the second color filter pattern; Forming a black matrix on the substrate including the third color filter pattern, wherein the second and third color filter patterns cover an edge of the first color filter pattern, and the first color filter pattern Provides a method for manufacturing a color filter substrate which is a blue color filter pattern.

Edges of the second color filter pattern and the third color filter pattern overlap each other.

The first to third color filter patterns are sequentially arranged in a first direction, and each of the first to third color filter patterns extends to an adjacent pixel area along a second direction.

The forming of the first color filter pattern may include forming an extension part extending in a first direction, and the extension part is covered with the second color filter pattern and the third color filter pattern.

In addition, the present invention, the above-mentioned color filter substrate; An insulating substrate spaced apart from the color filter substrate; A thin film transistor formed on the insulating substrate; A pixel electrode positioned in the pixel area on the insulating substrate and connected to the thin film transistor; The present invention provides a liquid crystal display device including a common electrode insulated from the pixel electrode and formed on the entire surface of the insulating substrate and having a plurality of openings on the pixel electrode.

In the color filter substrate for a liquid crystal display according to the present invention, external light reflection is formed by first forming a blue color filter pattern having the lowest reflectance on the substrate, followed by forming a red or green color filter pattern in turn, and then forming a black matrix. This can improve the contrast ratio.

In addition, when the color filter substrate of the present invention is applied to a high resolution liquid crystal display device, it is possible to prevent turbidity in the side viewing angle direction.

On the other hand, by further extending the blue color filter pattern to overlap the red and green color filter pattern, it is possible to further reduce the external light reflection.

1 is a cross-sectional view of a conventional liquid crystal display device.
2 is a cross-sectional view schematically illustrating a liquid crystal display device according to an exemplary embodiment of the present invention.
3 is a plan view schematically illustrating a color filter substrate according to an exemplary embodiment of the present invention.
4A to 4D are cross-sectional views illustrating color filter substrates at each stage of a manufacturing process of a color filter substrate according to an exemplary embodiment of the present invention.
5 is a plan view schematically illustrating a color filter substrate according to another exemplary embodiment of the present invention.
6 is a schematic cross-sectional view of a color filter substrate according to another exemplary embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

2 is a cross-sectional view schematically illustrating a liquid crystal display device according to an exemplary embodiment of the present invention.

As shown in FIG. 2, the liquid crystal display according to the exemplary embodiment of the present invention is disposed between the first and second substrates 110 and 150 and the first and second substrates 110 and 150 spaced apart from each other. The liquid crystal layer 190 is formed. Red, green, and blue pixel regions Pr, Pg, and Pb are defined on the first and second substrates 110 and 150.

A gate wiring (not shown) and a gate electrode 122 connected to the gate wiring are formed on the first substrate 110, and a gate insulating layer 124 is formed on the gate wiring and the gate electrode 122. The gate electrode 122 is formed corresponding to each of the red, green, and blue pixel regions Pr, Pg, and Pb.

The semiconductor layer 126 is formed on the gate insulating layer 124 corresponding to the gate electrode 122, and the source electrode 128 and the drain electrode 130 spaced apart from each other on the semiconductor layer 126, and the source electrode. A data line (not shown) connected to the 128 is formed.

Although not illustrated, the semiconductor layer 226 may include an active layer made of pure silicon and an ohmic contact layer made of impurity-doped silicon. The ohmic contact layer may have the same shape as the source and drain electrodes 128 and 130.

The data line crosses the gate line to define red, green, and blue pixel regions Pr, Pg, and Pb.

Here, the gate electrode 122, the semiconductor layer 126, the source electrode 128, and the drain electrode 130 constitute a thin film transistor Tr.

A first passivation layer 132 is formed on the source electrode 128, the drain electrode 130, and the upper surface of the data wire, and the first passivation layer 132 exposes the drain contact hole 132a. ) The first protective layer 132 may be formed of an organic insulating material and have a flat surface.

A pixel electrode 134 contacting the drain electrode 130 through the drain contact hole 132a is formed on each of the red, green, and blue pixel regions Pr, Pg, and Pb on the first passivation layer 132.

The second passivation layer 136 is formed on the entire upper surface of the pixel electrode 134, and the common electrode 138 is formed on the second passivation layer 136. The common electrode 138 is formed on the entire surface of the first substrate 110 and has a plurality of openings 138a corresponding to the pixel electrode 134.

Meanwhile, the color filter layer 160 is formed under the second substrate 150. The color filter layer 160 includes red, green, and blue color filter patterns 162, 164, and 166 corresponding to the red, green, and blue pixel areas Pr, Pg, and Pb, respectively. The red, green, and blue color filter patterns 162, 164, and 166 overlap each other, and the red color filter pattern 162 and the green color filter pattern 164 cover the edges of the blue color filter pattern 166.

The black matrix 172 is formed under the color filter layer 160 to correspond to the gate line, the data line, and the thin film transistor Tr. The black matrix 172 exposes the red, green, and blue color filter patterns 162, 164, and 166 of the red, green, and blue pixel areas Pr, Pg, and Pb, respectively.

An overcoat layer 180 is formed under the color filter layer 160 and the black matrix 172.

The liquid crystal layer 190 is positioned between the common electrode 138 of the first substrate 110 and the overcoat layer 180 of the second substrate 150. Although not shown, an alignment layer for determining an initial arrangement of liquid crystal molecules of the liquid crystal layer 190 is formed between the liquid crystal layer 190 and the common electrode 138 and between the liquid crystal layer 190 and the overcoat layer 180, respectively.

A first polarizing plate (not shown) and a second polarizing plate (not shown) are attached to a lower portion of the first substrate 110 and an upper portion of the second substrate 150, respectively, and a backlight unit (not shown) is disposed below the first polarizing plate. Is placed. In addition, a rear electrode made of a transparent conductive material may be further formed on the second polarizing plate.

In the liquid crystal display according to the present invention, since the color filter layer 160 is positioned below the second substrate 150 and the black matrix 172 is positioned below the color filter layer 160, reflection of external light by the black matrix 172 is prevented. This can increase the contrast ratio. The external light reflectance of the liquid crystal display according to the present invention can be improved by about 70 to 76% compared to the related art.

In this case, since the blue color filter pattern 166 having the lowest reflectance is positioned on the lower surface of the second substrate 150, the external light reflectance may be further reduced.

In addition, when the liquid crystal display device of the present invention is applied to a high resolution model, light passing through the liquid crystal layer 190 in one pixel area is adjacent to the color filter pattern by the black matrix 172 adjacent to the liquid crystal layer 190. It is easy to block the incident, and it is possible to prevent the clouding phenomenon in the side viewing angle direction.

3 is a plan view schematically illustrating a color filter substrate according to an exemplary embodiment of the present invention.

As shown in FIG. 3, the color filter substrate according to the embodiment of the present invention includes a color filter layer 160, and the color filter layer 160 is a red, green, and blue color filter sequentially arranged along a first direction. Patterns 162, 164, and 166. The red, green, and blue color filter patterns 162, 164, and 166 correspond to the red, green, and blue pixel areas Pr, Pg, and Pb, respectively, and the edges thereof overlap each other. In addition, the red, green, and blue color filter patterns 162, 164, and 166 extend in the second direction, and the red color filter patterns 162 corresponding to the adjacent red pixel regions Pr along the second direction are mutually different. The green color filter patterns 164 connected to and corresponding to the adjacent green pixel regions Pg in the second direction are connected to each other, and the blue color filter patterns corresponding to the adjacent blue pixel regions Pb in the second direction ( 166 are connected to each other. Each pixel region Pr, Pg, and Pb may have portions that are bent on the left and right sides thereof, and thus, the green and blue color filter patterns 162, 164, and 166 may also have respective pixel regions Pr, Pg, and Pb. It may have a bent portion.

The black matrix 172 is formed on the color filter layer 160, and the black matrix 172 is formed of the red, green, and blue color filter patterns 162, 164, of the red, green, and blue pixel regions Pr, Pg, and Pb. 166), respectively.

Meanwhile, the color filter layer 160 and the black matrix 172 are covered with an overcoat layer (not shown).

A method of manufacturing a color filter substrate according to an exemplary embodiment of the present invention will be described with reference to FIGS. 4A to 4D.

4A to 4D are cross-sectional views illustrating color filter substrates at each stage of a manufacturing process of a color filter substrate according to an exemplary embodiment of the present invention.

As shown in FIG. 4A, the blue pigment is coated on the insulating substrate 150 to form a blue color layer (not shown), and then the blue color layer is patterned through a photolithography process using an exposure mask. The color filter pattern 166 is formed.

Next, as shown in FIG. 4B, a red pigment is coated on the substrate 150 including the blue color filter pattern 166 to form a red color layer (not shown), followed by photolithography using an exposure mask. The red color layer is patterned through a process to form the red color filter pattern 162. In this case, the red color filter pattern 162 covers the edge of the blue color filter pattern 166.

Subsequently, as shown in FIG. 4C, a green pigment is coated on the substrate 150 including the blue color filter pattern 166 and the red color filter pattern 162 to form a green color layer (not shown). Thereafter, the green color layer is patterned through a photolithography process using an exposure mask to form a green color filter pattern 164 to complete the color filter layer 160. In this case, the green color filter pattern 164 covers the edges of the blue color filter pattern 166 and the red color filter pattern 162.

Here, although the red color filter pattern 162 is formed first and the green color filter pattern 164 is formed, the green color filter pattern 164 may be formed first and the red color filter pattern 162 may be formed. In this case, the red color filter pattern 162 covers the edges of the blue color filter pattern 166 and the green color filter pattern 164.

Next, as shown in FIG. 4D, a black resin is coated and patterned on the color filter layer 160 to form a black matrix 172. The black matrix 172 is positioned on the overlapped portions of the red, green, and blue color filter patterns 162, 164, and 166 and exposes the red, green, and blue color filter patterns 162, 164, and 166. In this case, the widths of the overlapped portions of the red, green, and blue color filter patterns 162, 164, and 166 are smaller than the width of the black matrix 172.

Next, an overcoat layer 180 is formed on the black matrix 172 and the red, green, and blue color filter patterns 162, 164, and 166. The overcoat layer 180 may be formed of an organic insulating material such as an acrylic resin.

5 is a plan view schematically showing a color filter substrate according to another embodiment of the present invention, and FIG. 6 is a cross-sectional view schematically showing a color filter substrate according to another embodiment of the present invention.

As shown in FIGS. 5 and 6, the color filter layer 260 is formed on the insulating substrate 250. The color filter layer 260 includes red, green, and blue color filter patterns 262, 264, and 266 respectively corresponding to the red, green, and blue pixel areas Pr, Pg, and Pb.

The red, green, and blue color filter patterns 262, 264, and 266 are sequentially arranged along the first direction, and edges thereof overlap each other. Here, the blue color filter pattern 266 including the extension part 266a is formed first, so that the red and green color filter patterns 262 and 264 have edges of the extension part 266a and the blue color filter pattern 266. To cover.

Meanwhile, although the green color filter pattern 264 covers the edge of the red color filter pattern 262 in the drawing, the red color filter pattern 262 may cover the green color filter pattern 264.

The red, green, and blue color filter patterns 262, 264, and 266 extend along the second direction, and the red color filter patterns 262 corresponding to the adjacent red pixel areas Pr along the second direction are connected to each other. In addition, the green color filter patterns 264 corresponding to the adjacent green pixel areas Pg in the second direction are connected to each other, and the blue color filter patterns 266 corresponding to the adjacent blue pixel areas Pb in the second direction. Are connected to each other. Each pixel region Pr, Pg, and Pb may have bent portions on the left and right sides thereof. As a result, the green and blue color filter patterns 262, 264, and 266 may also be formed with respect to the pixel regions Pr, Pg, and Pb. It may have a bent portion.

The extension part 266a of the blue color filter pattern 266 extends along the second direction and is connected to the adjacent blue color filter pattern 266. The extension part 266a is positioned between the red pixel area Pr and the green pixel area Pg adjacent in the second direction and overlaps the red color filter pattern 262 and the green color filter pattern 264. In this case, three layers of the extension part 266a, the red color filter pattern 262, and the green color filter pattern 264 may overlap in an area where the red color filter pattern 262 and the green color filter pattern 264 overlap. Can be.

A black matrix 272 is formed on the color filter layer 260, and the black matrix 272 has red, green, and blue color filter patterns 262, 264, and red in the red, green, and blue pixel regions Pr, Pg, and Pb. 266), respectively.

An overcoat layer 280 is formed on the color filter layer 260 and the black matrix 272 to cover them.

The color filter substrate according to another embodiment of the present invention may be manufactured by the same method as the color filter substrate according to the previous embodiment.

In the color filter substrate according to another exemplary embodiment of the present invention, an extension portion 266a of the blue color filter pattern 266 having the lowest reflectance is further formed to form a red color filter pattern 262 and a green color filter pattern 264. By overlapping, the external light reflection can be further reduced, and the external light reflectance can be improved by about 15.2% or more as compared with the previous embodiment.

The present invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit of the present invention.

110: first substrate 122: gate electrode
124: gate insulating layer 126: semiconductor layer
128: source electrode 130: drain electrode
132: first protective layer 132a: drain contact hole
134: pixel electrode 136: second protective layer
138: common electrode 138a: opening
150: second substrate 160: color filter layer
162: red color filter pattern 164: green color filter pattern
166: blue color filter pattern 172: black matrix
180: overcoat layer 190: liquid crystal layer
Pr: red pixel region Pg: green pixel region
Pb: blue pixel region

Claims (12)

A substrate in which pixel regions are defined;
A color filter layer formed on the substrate, each color filter layer including red, green, and blue color filter patterns sequentially arranged in a first direction corresponding to the pixel area;
A black matrix formed on and in contact with and overlapping the color filter layer and exposing the color filter layer of the pixel region;
Including,
The red and green color filter patterns cover edges of the blue color filter pattern.
And a overcoat layer covering the color filter layer and the black matrix, wherein the black matrix is positioned between the color filter layer and the overcoat layer.
The method of claim 1,
And each of the red, green, and blue color filter patterns extends to adjacent pixel areas in a second direction.
The method of claim 1,
And the edges of the red color filter pattern and the green color filter pattern overlap each other.
The method of claim 1,
The blue color filter pattern includes an extension part extending in the first direction, and the extension part is covered with the red color filter pattern and the green color filter pattern.
delete Forming a first color filter pattern on the substrate;
Forming a second color filter pattern on the substrate including the first color filter pattern;
Forming a third color filter pattern on the substrate including the second color filter pattern;
Forming a black matrix on the substrate including the third color filter pattern and in contact with and overlapping the first to third color filter patterns; And
Forming an overcoat layer covering the first to third color filter patterns and the black matrix
Including,
The second and third color filter patterns cover edges of the first color filter pattern, and the first color filter pattern is a blue color filter pattern.
And the black matrix is disposed between the first to third color filter patterns and the overcoat layer.
The method of claim 6,
And the edges of the second color filter pattern and the third color filter pattern overlap each other.
The method of claim 6,
The first to third color filter patterns may be sequentially arranged in a first direction, and each of the first to third color filter patterns may extend to adjacent pixel areas in a second direction. Way.
The method of claim 6,
The forming of the first color filter pattern may include forming an extension part extending in a first direction, wherein the extension part is covered with the second color filter pattern and the third color filter pattern. Method for manufacturing filter substrate.
A color filter substrate according to any one of claims 1 to 4;
An insulating substrate spaced apart from the color filter substrate;
A thin film transistor formed on the insulating substrate;
A pixel electrode positioned in the pixel area on the insulating substrate and connected to the thin film transistor;
A common electrode insulated from the pixel electrode and formed on the entire surface of the insulating substrate and having a plurality of openings on the pixel electrode;
Liquid crystal display comprising a. The method of claim 1,
And the black matrix is positioned on the overlapped portions of the red, green and blue color filter patterns, and the width of the overlapped portions of the red, green and blue color filter patterns is narrower than the width of the black matrix.
The method of claim 6,
The black matrix is positioned on the overlapped portions of the first, second and third color filter patterns, and the width of the overlapped portions of the first, second and third color filter patterns is greater than the width of the black matrix. Method for manufacturing narrow color filter substrate.

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