JPH0566306A - Production of color filter - Google Patents

Abstract

PURPOSE:To improve the flatness of color filters and the electrodes thereon by forming the color filters on a substrate, applying a light shielding film thereon and polishing the film. CONSTITUTION:The color filters 16 of prescribed patterns are formed on the transparent substrate 10 and the light shielding film 17 is applied on the color filters 16. The surface of the light shielding film 17 is so polished as to expose the surfaces of the color filters 16. The light shielding film 17 is applied after the color filters 16 are formed in such a case. The light shielding film 17 fills the microspacings between the respective picture element regions of the color filters 16 and covers the surfaces of the color filters 16. The surfaces of the color filters 16 are, thereupon, flattened if the surface of the light shielding film 17 is so polished as to expose the surface of the color filters 16. Since the microspacings between the respective picture element regions of the color filters 16 are filled with the light shielding film 17, the relatively wide surfaces are uniformly polished and gases, etc., do not intrude into the spacings. In addition, patterns for inspecting the film thickness of the color filters are provided on the outer side of the color filter regions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color filter used in a liquid crystal display device or the like. Liquid crystal display devices have characteristics such as thinness, light weight, and low power consumption. Demand is increasing for OA equipment, personal computers, televisions, and the like, and color display is becoming popular. As the demand increases in this way, there is a demand for improving the display quality of liquid crystal display devices.

[0002]

2. Description of the Related Art A liquid crystal display device is one in which liquid crystal is enclosed between a pair of transparent substrates, and a liquid crystal display device for color display has a color filter on one of the pair of transparent substrates. Is formed. Further, a light-shielding film (black matrix) is provided so as to partition each pixel region of the color filter of this substrate. Further, electrodes are formed on the pair of transparent substrates so that a voltage can be applied to each pixel region of the liquid crystal.

FIG. 7 is a diagram showing a conventional manufacturing procedure of one substrate having a color filter. Conventionally, as shown in (A), the light shielding film 2 is first provided on the surface of the substrate 1. This light shielding film 2 is called a black matrix,
It is formed in a grid pattern in which each pixel region is opened, and is usually formed by photolithography. next,
As shown in (B), a colored resist 3 made of a photo-curable resin in which color pigments are dispersed is applied onto the light-shielding film 2, and after exposure through a mask, as shown in (C). Then, the color filter 4 for one color (for example, R) was formed by etching. Then, the same processing is repeated for the other two colors, and after forming the color filters 5 and 6 for the other two colors (for example, G and B), as shown in (D), the insulation overcoating is further performed. The coat 7 was applied, and the electrode 8 was formed thereon.

[0004]

In the conventional method of manufacturing a color filter described above, as shown in FIG. 7B, when the colored resist 3 is applied onto the light shielding film 2 (and after that). The portion 3 of the colored resist 3 located on the light-shielding film 2 when the colored resist of another color is applied.
a tends to protrude upward, and as shown in (C), the protruding portion 4a may remain in a part of the color filter 4 even after etching. for that reason,
As shown in (D), overcoat 7 and electrode 8
There was a case where the surface of the was uneven and the flatness was lowered.

If the flatness of the surfaces of the color filters 4, 5, 6 and the electrode 8 is low, the transmission of light becomes uneven, and problems such as color unevenness occur and display quality deteriorates. It was An object of the present invention is to provide a method of manufacturing a color filter, which can improve the flatness of the color filter and the electrodes thereon.

[0006]

A method of manufacturing a color filter according to the present invention will be described with reference to FIG.
A color filter 16 having a predetermined pattern is formed on (A), a light-shielding film 17 is applied on the color filter 16 (B), and the surface of the light-shielding film 17 is exposed so that the surface of the color filter 16 is exposed. It is characterized by comprising the step (C) of polishing.

[0007]

According to the above construction, the light-shielding film 17 is applied after the color filter 16 is formed, and the light-shielding film 17 fills the minute gaps between the respective pixel regions of the color filter 16 to form the color filter 16. Cover the surface. Therefore, when the surface of the light shielding film 17 is polished so that the surface of the color filter 16 is exposed, the surface of the color filter 16 becomes flat. Since the minute gaps between the pixel regions of the color filter 16 are filled with the light-shielding film 17, a relatively wide surface can be uniformly polished, and dust or the like does not enter the gaps.

[0008]

EXAMPLE FIG. 6 shows an example of a liquid crystal panel of a liquid crystal display device. The liquid crystal panel comprises a pair of transparent substrates 10 and 12 in which a liquid crystal 14 is sealed. A color filter 16 and a light shielding film (black matrix) 17 are formed on one substrate 10, and an overcoat 18 and an electrode 19 are further formed thereon. An electrode 20 is formed on the other substrate 12. The electrode 20 is formed for each pixel as an active matrix driving electrode, and the first electrode 19 is formed on the entire surface. The present invention relates to the formation of the color filter 16 and the light shielding film 17 on the one substrate 10.

FIG. 2 is a diagram showing a first embodiment of the present invention. As shown in (A), the color filter 16 having a predetermined pattern is formed on the transparent substrate 10. The color filter 16 can be formed by the pigment dispersion method using photolithography according to the procedure shown in FIG.
In FIG. 3, as shown in FIG.
The colored resist 25 made of a photo-curable resin in which the coloring matter pigment is dispersed is applied by spin coating or the like, and as shown in (B), after exposure through the mask 26, (C)
As shown in FIG. 3, the color filter 16R for one color (for example, R) is formed by etching. Then repeat the same process for the other two colors,
As shown in (D), color filters 16G and 16B for the other two colors (for example, G and B) are formed. These color filters 16R, 16G, 16B are provided for each pixel area. 1, FIG. 2, and FIG. 4, all of these color filters 16R, 16G, and 16B are indicated by the color filter 16.

The colored resist 25 of each color and the like are commercially available in a state where a pigment is dispersed in a photocurable resin. In the present invention, a pigment having a specific particle size is further mixed into the commercially available colored resist 25 or the like so that the color filters 16R, 16G and 16B of the respective colors have the same height. By adjusting the particle size of the mixed pigment, the light transmittance is adjusted and the chromaticity is stabilized.

Further, as shown in FIG.
When the color filter 16 is formed, the color filter 16
An additional pattern 28 having the same thickness as the color filter 16 and having an area larger than the individual area of the color filter 16 (16R, 16G, 16B) is formed outside the formation area of the color filter 16. This additional pattern 28 can be formed simultaneously when forming at least one color of the color filter 16. For example, the opening of the mask 26 shown in FIG. 3 may be additionally provided. This additional pattern 28
Is used to inspect the film thickness of the color filter 16 during or after polishing. For example, the film thickness of the color filter 16 is determined by measuring the light transmittance of the additional pattern 28.

In FIG. 2, when the formation of the color filter 16 is completed, a light shielding film 17 is applied on the color filter 16 as shown in FIG. In the embodiment of FIG. 2, the light shielding film 17 is applied by a printing method.
Next, as shown in (C), the surface of the light shielding film 17 is polished so that the surface of the color filter 16 is exposed. This polishing can be carried out by the polishing apparatus shown in FIG.

The polishing apparatus shown in FIG. 5 is a kind of lapping machine and includes an upper surface plate 30 and a lower surface plate 32 which are opposed to each other, and the substrate 10 having the color filter 16 and the light shielding film 17 is attached to the upper surface plate 30. It is like this. For this reason, the upper surface plate 30 has a vacuum suction port (not shown) for holding the substrate 10 in the central portion, and a work holder 33 for fixing the peripheral portion of the substrate 10. Lower surface plate 3
2 is attached with an abrasive holding member 35 made of cloth or the like soaked with fine abrasive 34. Therefore,
When the lower surface plate 32 is rotated, the substrate 1 is removed by the abrasive material 34.
The 0 color filter 16 and the light shielding film 17 are polished.
The upper surface plate 30 is not particularly driven, but is rotated by the rotation of the lower surface plate 32.

The light-shielding film 17 covers the surface of the color filter 16 by filling the minute gaps between the pixel regions of the color filter 16, and the surface of the light-shielding film 17 is exposed so that the surface of the color filter 16 is exposed. By polishing, the surface of the color filter 16 becomes flat. Color filter 16
Since the minute gaps between the respective pixel regions are filled with the light-shielding film 17, a relatively wide surface can be uniformly polished, and dusts and the like do not enter the gaps.

In FIG. 2, an overcoat 18 made of an insulating material is applied in (D), and a full-surface electrode 19 is formed in (E).

FIG. 4 is a diagram showing a second embodiment of the present invention. In the second embodiment, the color filter 16 and the additional pattern 28 in (A) are the same as in the first embodiment.
After forming, the light shielding film 17 is applied by spin coating as shown in FIG. The light-shielding film 17 is made of an insulating resist, and as shown in (C), the peripheral portion is removed by etching after exposure with a mask. Thereafter, as shown in (D), the light shielding film 17 is polished to flatten the surface of the color filter 16. Next, as shown in (E), the electrode 19 is formed. In this embodiment, the overcoat 18 on the color filter 16 is omitted. Overcoat 1
Since 8 is formed flat and the light-shielding film 17 is made of an insulating material, the overcoat 18 can be omitted. The overcoat 18 can be provided also in the second embodiment, or
In the first embodiment, the overcoat 18 can be omitted.

[0017]

As described above, according to the present invention,
The surface of the color filter can be made flat, which can improve the display quality when applied to a display device such as a liquid crystal display device.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a diagram showing a first embodiment of the present invention.

FIG. 3 is a diagram showing formation of color filters.

FIG. 4 is a diagram showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a polishing apparatus.

FIG. 6 is a diagram showing a liquid crystal panel.

FIG. 7 is a diagram showing a conventional technique.

[Explanation of reference numerals] 10 ... Substrate 16 ... Color filter 17 ... Light-shielding film

Claims (3)

[Claims] 1. A color filter (16) having a predetermined pattern is formed on a transparent substrate (10), and a light-shielding film (17) is applied on the color filter (16) to form a color filter (16). The light shielding film (17) so that the surface is exposed
A method of manufacturing a color filter, which comprises a step of polishing the surface of the. 2. When the color filter (16) is formed, an additional pattern (28) having the same thickness as the color filter and having an area larger than the individual area of the color filter is formed outside the area where the color filter is formed. ) Is formed so that the film thickness of the color filter can be inspected during or after polishing, and the method for producing a color filter according to claim 1. 3. The method for producing a color filter according to claim 1, wherein the color filter (16) is composed of a photocurable colored resist in which a pigment is dispersed.