JPH03181903A - Production of color filter - Google Patents

Abstract

PURPOSE:To eliminate the need for exposing on light shielding films and to obtain desired patterns by forming the patterns of a positive type photosensitive resin on the light shielding films, then forming desired color films. CONSTITUTION:After the positive type photosensitive resin having absorptivity to the wavelength of the light to be used at the time of patterning of black dyed layers 2 is applied on a semiconductor substrate 1, the parts exclusive of the light shielding films 12 are exposed away, by which the patterns 21 of the positive type photosensitive resin are formed on the light shielding films 12. A photosensitive soln. mixture is then applied on the surface and is exposed on the light shielding films 12, by which the patterns are formed on the light shielding films 12; further, the patterns are immersed into a black dye, by which the black dye layers 2 are formed. After a transparent resin layer 31 is applied on the surface, a photosensitive soln. mixture is applied and is patterned to desired positions by using a photomechanical technique; further, the substrate is immersed into a desired dye, by which the dyed layer 34 of the 1st color is formed. The desired patterns are easily formed on the light shielding films 12 in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a color filter used in a solid-state image sensor.

[Conventional technology]

FIG. 2 is a sectional view of a solid-state image pickup device with a color filter showing the structure of a conventional color filter disclosed in, for example, Japanese Patent Application Laid-open No. 57-148366 and Japanese Patent Application Laid-Open No. 57-117277. In the figure, 1 is a semiconductor substrate with a solid-state image sensor formed on its surface, 2 is a black dye layer, 3 is a color filter layer, 11 is a light receiving element (pixel), and 12 is an A
31, 32, 33 are transparent resin layers, 34 is a dyed layer of the first color, and 35 is a dyed layer of the second color.

The color filter configured as described above is formed as follows. That is, a liquid mixture of ceratin and the like to which a photosensitive agent such as ammonium dichromate is added is applied onto the semiconductor substrate 1 on which the solid-state image sensor is formed without a housing, and the light-shielding film 12 other than the pixels 11 is formed using photolithography technology. Butter the top. Further, this is immersed in a black dye to form a black dyed layer 2. Next, after applying a transparent resin layer 31, a mixed solution of ceratin and the like to which a photosensitive agent such as ammonium dichromate is added is applied, and patterned at a desired position using photolithography. Further, this is immersed in a desired dye to form a dyed layer 34 of the first color. Next, after applying the transparent resin layer 32, a dyed layer 35 for the second color is formed using the same procedure as for the first color. Finally, a transparent resin layer 33 is applied as a protective film to complete the process.

[Problem to be solved by the invention]

However, according to the conventional method of manufacturing color filters, when forming the black dyed layer 2, a mixture of ceratin and ammonium dichromate is used as a negative photosensitive resin layer. It is necessary to expose the light-shielding film 12 of the reflectance, and therefore, the ceratin etc. receive a large amount of light compared to the amount of light that was actually exposed, causing problems such as not being able to obtain the desired pattern. there were.

[Means to solve the problem]

In order to solve these problems, the present invention forms a desired color filter after forming a positive photosensitive resin pattern on a light shielding film.

[Effect]

Since the positive type photosensitive resin in this invention is positive type, when leaving a pattern on the light shielding film, there is no need to expose the light shielding film, so that the desired pattern can be obtained. Further, when forming the black dyed layer, the positive photosensitive resin layer absorbs reflected light from the light shielding film.

〔Example〕

Embodiments of this invention will be described in detail (3) below using drawings. explain.

FIG. 1 is a sectional view of a solid-state image sensing device with a color filter for explaining an embodiment of the method for manufacturing a color filter according to the present invention, and the same parts as in the previous figures are given the same reference numerals. In the figure, first, a positive type film having absorbency in the wavelength of light used when patterning a black dye layer 2 is placed on a semiconductor substrate 1 on which pixels 11 as a solid-state image sensor and a light shielding film 12 are formed. After applying the photosensitive resin, the portions other than those on the light shielding film 12 are exposed and removed, thereby forming a positive photosensitive resin pattern 21 on the light shielding film 12. Next, a photosensitive mixed solution made by adding ammonium dichromate or the like to ceratin, casein, polyvinyl alcohol, etc. to impart photosensitivity is applied, and the light shielding film 12 is exposed to light to form a pattern on the light shielding film 12, Further, this pattern is immersed in black dye to form a black dyed layer 2. Next, after applying a transparent resin layer 31, a photosensitive mixed solution in which ammonium dichromate or the like is added to ceratin, casein, polyvinyl alcohol, etc. to impart photosensitivity (4) is applied, and photolithography is used to apply the photosensitive mixed solution. A dyed layer 34 of the first color is formed by patterning at a desired position and further immersing it in a desired dye. Next, after coating the transparent resin layer 32, a dyed layer 35 for the second color is formed using the same procedure as for the first color to complete the process.

In addition, in the above-described embodiment, a case was explained in which the black dyed layer 2 was formed on the positive photosensitive resin pattern 21, but the black dyed layer 2 was not provided and the positive photosensitive resin pattern 2 was formed on the positive photosensitive resin pattern 21.
The color filter layer 3' may be formed directly on the color filter layer 1. In this case, it is possible to prevent the pattern shapes of the first color staining M34 and the second color staining J135 from being deteriorated by the reflected light from the light shielding Ji12.

Moreover, the same effect can be obtained without forming the black dyed layer 2 by adding an absorbent having absorbency at a desired wavelength to the positive photosensitive resin pattern 21.

Furthermore, in the above embodiment, three layers of dyeing M2°34.
Although the case has been described in which the color filter layer 3' is constructed by laminating the color filter layer 35 and the transparent resin IflI31, 32, and 33 of three eyebrows, the structure of the color filter layer 3/ is not strictly limited.

In addition, although the case where the black dyeing NI2 is formed directly on the positive photosensitive resin pattern 21 has been described, it is also possible to form the black dyeing layer 2 after forming the transparent resin layer on the positive photosensitive resin pattern 21. good.

〔Effect of the invention〕

As explained above, according to the present invention, a positive photosensitive resin pattern that absorbs the exposure wavelength of the next layer is formed on the light shielding film, so that when the next layer is exposed, the light reflected from the light shielding film is Since it is absorbed by the photosensitive resin pattern, it is possible to easily form a desired pattern even on a light-shielding film, which is an extremely excellent effect.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a solid-state image sensor with a color filter for explaining an embodiment of the method of manufacturing a color filter according to the present invention, and FIG. 2 is a cross-sectional view of a conventional solid-state image sensor with a color filter. 1... Semiconductor substrate, 11... Pixel, 12...
- Light-shielding film, 2... Black dyed layer, 21... Positive photosensitive resin pattern, 3'... Color filter layer,
31.32, 33... Transparent resin layer, 34... First color dyed layer, 35... Second color dyed layer.

Claims (1)

[Claims] 1. A method for manufacturing a color filter, which comprises forming a positive photosensitive resin pattern on a light-shielding film of a semiconductor substrate having pixels and a light-shielding film on its surface, and then forming a desired color filter.