JPS63208803A - Production of color filter - Google Patents

Abstract

PURPOSE:To obtain a color filter pattern which does not generate overlapping of adjacent filter patterns by forming an intermediate layer consisting of an optically transparent inorg. material along or the optically transparent inorg. material and optically transparent resin material on a color filter pattern of a lower layer. Then forming the color filter patterns of the respective layers at the time of forming the color filter patterns of the 2nd and ensuing colors. CONSTITUTION:After the color filter pattern 6a of the 1st color is formed, an inorg. coating film material essentially consisting of silicon oxide is in succession spin-coated thereon and is subjected to a heat treatment, by which the intermediate layer 3 is formed. A high-polymer material such as transparent polyimide resin previously mixed with a green coloring agent is spin-coated on the intermediate layer 3 and is subjected to a heat treatment, by which the colored layer 7 of the 2nd color is formed. The photoresist pattern 22 is then formed in the same manner as in the case of the 1st color. The similar stage is thereafter repeated. The color filter pattern having good dimensional accuracy is thereby obtd. without damaging the color filter pattern of the lower layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a color filter used in solid-state image sensors, liquid crystal displays, and the like.

[Conventional technology]

Conventionally, gelatin has been used as a color filter for solid-state image sensors or liquid crystal displays.

Casein, glue, PVA (polyvinyl alcohol)
In many cases, a filter pattern made of a material to be dyed, such as a filter pattern, is formed using a so-called "dying method" in which a color filter pattern is formed by dyeing a material to be dyed, such as, with an acid dye or the like. For example, FIG. 7 is a cross-sectional view of a color filter formed by a conventional color filter manufacturing method. A protective layer formed on the top layer, 6a.

7a and 8a each represent the first color (for example, red).

A color filter pattern 10 for a second color (for example, green) and a third color (for example, blue) is a color filter configured as described above.

In such a conventional color filter manufacturing method, for example, after forming the base layer 1, a pattern of a wavy color layer made of photosensitive gelatin or casein is formed by photolithography, and then this is coated with an acidic material. A first color filter pattern 6a is obtained by dyeing with a method such as dyeing, and then an intermediate layer 3 for preventing color mixture with the second color is formed, and a second color filter pattern 7a is applied thereon. The color filter was formed by the same method as in the case of the above-mentioned case, and then the same steps as above were repeated for the required number of colors.

[Problem that the invention seeks to solve]

In conventional methods for producing color filters using such dyeing methods, color filter patterns were obtained by dyeing dyed patterns formed with gelatin, casein, etc.; There was a problem in that the pattern swelled significantly compared to before dyeing, causing pattern dimensions to fluctuate and accuracy to decline. In addition, this expansion IJl causes drooping at the edges of the pattern, which causes overlap with adjacent color filter patterns, resulting in a decrease in the accuracy of color separation.

This invention was made in order to solve the above-mentioned problems, and provides a method of manufacturing a color filter that can obtain a color filter pattern with high dimensional accuracy (and where adjacent color filter patterns do not overlap). The purpose is to

[Means for solving problems]

The method for manufacturing a color filter according to the present invention includes forming a resist pattern on a colored layer laminated on a substrate, and etching the colored layer using the resist pattern as a mask to remove unnecessary portions to form a color filter pattern. Before forming the second and subsequent colored layers, an intermediate layer made of an optically transparent inorganic material or an intermediate layer made of an optically transparent inorganic material and an optically transparent resin material is formed. It was designed so that it could be formed.

[Effect]

In the method for manufacturing a color filter according to the present invention, a color filter pattern is formed by etching, notching and removing unnecessary portions of the colored layer using a resist pattern as a mask, thereby forming a color filter pattern with high dimensional accuracy. In addition, when etching the colored layers of the second and subsequent colors, an intermediate layer made of an inorganic material is formed, which acts as an etching stopper and prevents damage to the underlying color filter pattern. , color filter patterns for the second and subsequent colors can also be formed with good precision.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
6 to 6 show a method of manufacturing a color filter according to an embodiment of the present invention, and in the figures, 1.3 to 5. and 5
a, 7a, and 8a indicate parts that are the same as or correspond to those in the conventional color filter manufacturing method shown in FIG. 21 and 22 are resist patterns formed corresponding to the color filter patterns of the respective colors.

Next, the process will be explained.

In FIG. 1, a first color colored layer (red) 6 is formed by spin-coating a polymeric material such as transparent polyimide resin mixed with a red coloring agent in advance onto a substrate and applying heat treatment.

Next, a photoresist is spin-coated on the colored layer 6, a pattern corresponding to the pattern of the color filter to be formed is exposed and transferred using a chrome mask, and then developed to obtain a photoresist pattern 21. .

Next, the thickness of the colored layer 6 of the first color is 1.0 μm.

When the thickness of the photoresist 21 is 1.0 μm, for example, if dry etching is performed for 5 minutes under the conditions of RF output of 200 W, substrate temperature of 80° C., and oxygen gas partial pressure of 1.2 Torr, the photoresist 21 becomes a mask. , only the areas without photoresist are etched. After the etching is completed, the photoresist 21 is removed by further dry etching or treatment with a suitable solvent to obtain a first color filter pattern 6a having a shape as shown in FIG.

Subsequently, an inorganic coating material containing silicon oxide (S i 02 ) as a main component is applied by spin coating, and heat treatment is applied to form the intermediate layer 3 . Next, a polymeric material such as a transparent polyimide resin premixed with a green coloring agent is spin-coated onto the intermediate layer 3 and heat-treated to form a second colored layer [green] 7. Subsequently, a photoresist pattern 22 is formed in the same manner as in the case of the first color.

Next, using this as a mask, dry etching is performed using 02 plasma in the same manner as above. In this case, the intermediate layer 3 made of an inorganic substance acts as an etching stopper and prevents etching from proceeding to the first color filter pattern 6a. After etching is completed, photoresist 2
By removing 2, a color filter pattern 7a of the second color as shown in FIG. 4 is obtained.

Thereafter, by repeating the same process as above, a third color filter pattern (blue) 8 as shown in FIG.
a is obtained.

Thereafter, as shown in FIG. 6, in order to protect the color filter pattern from scratches, a protective layer 5 made of a transparent resin material is formed as the uppermost layer to form a color filter 10.

Although it has been described above that the intermediate layer is formed only of an optically transparent inorganic material, this intermediate layer may be formed using a transparent resin material together with an optically transparent inorganic material.

The polymer material for the colored layer used in this example is, for example, mainly polyglycidyl methacrylate, which has excellent light transmittance and has a molecular weight of several hundred thousand or more, and Lewis acids such as BF3, which is an epoxy reaction initiator. The above-mentioned copolymers are made by copolymerizing glycidyl methacrylate with methacrylic esters such as methyl methacrylate, acrylic esters, and even styrene. materials to which acids, acid anhydrides, amine salts, etc. have been added, thermosetting transparent resin materials such as chlorinated polymethylstyrene or chloromethylpolystyrene with a molecular weight of several hundred thousand or more, or optically transparent polyimide resins. Can be used. A mixture of these polymeric materials with dyes, pigments, and other additives for coloring is used as a material for forming the colored layer. For example, dyes include anthraquinone, azo, phthalocyanine, methine,
Various types such as oxazine type or metal-containing complex salt type of these can be used, and coloring agents such as inorganic pigments pulverized to a particle size of 1 μm or less can also be used.

In addition, the photoresist must be able to obtain a sufficient etching rate during dry etching of the colored layer. For example, as a positive resist, phenol-novolac-based AZ-1350 (manufactured by Shipley) and 0FP are used.
R-800 (manufactured by Tokyo Ohka Kogyo Co., Ltd.), and high-resolution negative resists such as CMS (manufactured by Toyo Soda Co., Ltd.) and MES (manufactured by Japan Synthetic Rubber Co., Ltd.) are available for far ultraviolet rays. However, it is not limited to these.

Further, as a material for forming the intermediate layer, a coating film material mainly composed of a silicon compound such as silicon oxide can be used, such as OCD (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Note that as the optically transparent resin material, the colored layer forming material that does not contain the above-mentioned coloring agent can be used.

Furthermore, as the material for the uppermost layer of the protective film, the thermosetting transparent resin, polyimide resin, or photocuring transparent resin mentioned above as the polymer material for the colored layer can be used.

In the above embodiment, a method for manufacturing a color filter consisting of three colors was shown, but it goes without saying that the method according to the present invention can also be applied to forming a color filter consisting of only one color or two colors.

Further, in the above embodiment, the color filter pattern 5a.

7a and 8a show cases in which transparent synthetic polymer materials such as polyimide resin are mixed with coloring agents such as dyes and pigments, but it is possible to Mix to impart photocurability and use a mixture of the above colorants as a material, or add a colorant such as a dye or pigment and a photosensitizer such as ammonium dichromate to a natural polymer material such as gelatin or casein. The mixed material was used as a material, and this was photocured to form a colored layer of 6.7°8.
may be formed.

〔Effect of the invention〕

As described above, according to the method of manufacturing a color filter according to the present invention, the intermediate layer made of an inorganic material is used as an etching stopper, and the colored layer is etched using the resist pattern as a mask to form a color filter pattern. Therefore, it is possible to obtain a color filter pattern with good dimensional accuracy without damaging the previously formed color filter pattern in the lower layer, and there is no overlap between adjacent color filter patterns, resulting in color separation with high accuracy. It has the effect of providing a filter.

[Brief explanation of the drawing]

1 to 6 are cross-sectional views of a color filter showing a method of manufacturing a color filter according to an embodiment of the present invention, and FIG. 7 is a cross-sectional view of a conventional color filter. 3.4... Intermediate layer, 5... Protective layer, 6, 7.8...
- Colored layers of the first color, second color, and third color, 6a, 7a
, Qa... Color filter patterns of first color, second color, third color, 21.22... Photoresist pattern. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (2)

[Claims] (1) A color filter manufacturing method in which a color filter is formed on a substrate, which includes a step of laminating a colored layer on the substrate or an intermediate layer to be described later, a step of forming a resist mask on the colored layer, and an etching process. The step includes a step of removing unnecessary portions of the colored layer that are not covered by the resist mask, and a step of forming a color filter pattern for each color. A color filter characterized in that a color filter pattern of each color is formed after forming an intermediate layer consisting of an optically transparent inorganic material alone or an optically transparent inorganic material and an optically transparent resin material. manufacturing method. (2) After forming a color filter pattern with the desired number of colors,
2. The method of manufacturing a color filter according to claim 1, wherein an optically transparent protective film is formed as the uppermost layer.