JPS62257104A - Color filter - Google Patents

Abstract

PURPOSE:To reduce color blur and color mixing by removing corners of filters which are closest to each other in the diagonal line direction of a color separation filter layer or four corners of respective filters slantingly upon occasion and increasing their gap when forming the color separation filter layer. CONSTITUTION:When the color separation filter layer 14 is formed, gelatin is patterned by using a mask having such a pattern that four corners of areas 17 transmitting light are removed slantingly, namely, that gaps, specially, at corners of the color separation filter layer are increased, and consequently the pattern having its four corners removed slantingly is formed and never spread to areas where the color separation filter layer 14 should not be present originally. This pattern is dyed in, for example, green G and then the entire surface is coated with an intermediate film; and a necessary pattern where four corners of respective filter layers are removed slantingly is used to form a red R filter layer and a blue B filter layer successively, thus obtaining a color filter which is free of color blur and color mixing.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a color filter formed on an optically transparent substrate or a solid-state image sensor, and particularly relates to a color filter that requires microfabrication and a large number of pixels. It is something.

<Prior art> Conventionally, as a method for forming a color filter for color separation on a transparent substrate or a solid-state image sensor, for example, a dyeable photosensitive film such as gelatin added with a photosensitive agent is formed on the substrate. After patterning, a color element-receiving layer is formed by dyeing with a dye having predetermined spectral characteristics, or by vacuum deposition of an inorganic material such as a metal oxide, and as necessary, predetermined color elements are formed before and after the patterning. There is a method of coloring so that it has spectral characteristics. The former method will be explained in more detail with reference to FIG.

As shown in Figure 2, a photoresist film 2 made of a dyeable material such as polyvinyl alcohol, casein, or gelatin that has been made photosensitized with ammonium dichromate, etc. is uniformly coated on the surface of a substrate 1, and then dried. Only the pattern portion of the first color is photocured by a post-mask exposure method ((B) in the same figure) and developed to form a desired pattern 3 ((C) in the same figure). Next, this pattern 3 is dyed with, for example, a red dye to form a first color red filter layer 4 (CD) in the same figure), and a transparent resist dyeing film 5 is applied to the entire surface to prevent color mixing (■ in the same figure).
.

Next, in the same manner, a photoresist film is coated on this resist dye film 5, and a pattern is formed through drying, pattern exposure, and development.This pattern is then dyed with, for example, green dye.
A green filter layer 6 of the second color is formed, and an anti-dyeing film 7 is applied to the entire surface.

Next, in the same manner, a photoresist film pattern is formed on the resist dyeing film 7, and this time, this pattern is dyed with, for example, blue dye to form a third color blue filter layer 8, and finally, the entire pattern is dyed. A color filter formed on the substrate 1 is obtained by depositing a surface protective film 9 on the surface ((G) of the same figure).

<Problems to be Solved by the Invention> In such color filters, a negative photoresist film is used as the material for the color separation filter layer, so when this is exposed with a desired mask and developed, the horizontal direction of the pattern is Because of its expansion, it tends to be larger than the mask design and dimensions. Therefore, as patterns become finer, this phenomenon of lateral expansion cannot be ignored.)
This causes problems such as color bleeding and color mixing in the color filter.

For example, when patterning a color separation filter layer with a pattern mask (FIG. 3(A)) in which the light transmitting area 10 is rectangular as shown in FIG. 3, if the pattern is fine, the nearest adjacent filter layer If the distance between the two layers is very short, the color separation filter layer (1) will reach the area 12 where it should not exist, as shown in Figure (B), and color bleeding and color mixing will occur. Become.

Means for Solving the Problems> The present invention has been made in view of the problems of the conventional color filters described above. For areas where the spacing between the layers is narrow, change the shape of each color separation filter layer, for example by removing the corners of each filter, or the four corners of each filter diagonally as necessary, to widen the spacing. The present invention provides a color filter that reduces the influence on other color division filter layers.

<Example> As shown in FIG. 1, a dyeable material having negative photosensitivity, such as ammonium dichromate, was added as a photosensitizer onto a substrate 13 such as a transparent glass substrate or a solid-state image sensor. When forming the color separation filter layer 14 using gelatin, the area 15 that transmits light is patterned to form the gelatin.

A mask with a pattern in which the corners of the four corners are removed diagonally, that is, the distance between the color separation filter layers is increased, especially at the corners (
By patterning in the same figure), a pattern is formed in which the four corners are removed diagonally, and it does not extend to the region 16 where the multi-color separation filter layer 14 should not exist (in the same figure). B) )o After dyeing this pattern with green (G), for example, an interlayer film is applied to the entire surface. Subsequently, similarly, by sequentially forming a red 03) filter layer and a blue 03) filter layer using a desired pattern in which the four corners of each filter layer were removed diagonally,
A color filter without color bleeding or color mixing is completed ((C) in the same figure).

The above example describes the case where gelatin is used as the color separation filter layer, but other synthetic polymer materials such as polyvinyl alcohol and acrylic resin, or natural polymer materials such as zein, which is a substitute for the above gelatin, may also be used. It can also be manufactured.

Furthermore, the present invention is not limited to organic filters, but can also be applied to inorganic filters in which color element receiving layers are formed of inorganic materials.

<Effects of the Invention> As described above, in the present invention, when forming a color separation filter layer, the corner of each filter nearest to the diagonal direction of the color separation filter layer, or the four corners of each filter as necessary, is By removing diagonally and increasing the spacing,
Color filters without color bleeding or color mixing can be formed.

[Brief explanation of drawings]

The first country and (B) are masks for patterning a color separation filter layer in a color filter according to the present invention;
A diagram showing an example of the shape of the color separation filter layer after patterning, and (C) a diagram showing an example of a color filter, and Figures 2 to (G) are for explaining a conventional method of manufacturing a color filter. FIG. 3B is a cross-sectional view showing a mask for patterning a color separation filter layer in a conventional color filter and the shape of the color separation filter layer after patterning. 1.13: Substrate, 2: Photoresist film, 4.6°s, (
1). 14: Color separation filter layer, 5, 7: Anti-dyeing film,
9: Protective film, 10, 15: Area through which light passes, 12, 16: Area where color separation filter layer (1) or 14 should not exist. Agent: Patent attorney: Itaru Sugiyama (and 1 other person) (A)
(El) Figure 3 (C)

Claims (6)

[Claims] (1) In a color filter in which at least one color separation filter layer of a desired shape is formed on a substrate, the corners of each filter closest to each other in the diagonal direction of the color separation filter layer are removed to form obtuse angles. A color filter characterized by being formed. (2) The color filter according to claim 1, characterized in that four corners of each filter of the color separation filter layer are removed. (3) In claim 1 or 2, the color separation filter layer includes a synthetic polymer material such as polyvinyl alcohol or acrylic resin, or a natural polymer material such as casein or gelatin. Characteristic color filter. (4) The color filter according to claim 1 or 2, wherein the color separation filter layer is made of an inorganic material such as a metal oxide or a metal fluoride. (5) The color filter according to claim 1 or 2, wherein the colors imparted to the color separation filter layer are three primary colors of light or complementary colors. (6) The color filter according to claim 1, wherein the substrate is an optically transparent substrate such as glass or a solid-state image sensor.