JPS6041005A - Color filter manufacturing method - Google Patents

Abstract

PURPOSE:To form a hard-to-peel layer by forming a gelatine layer on the semiconductor substrate of a solid-state image pickup element which has a photodetection part and exposing and developing it through a mask pattern, and then performing a heat treatment within a specific temperature range and dyeing the layer. CONSTITUTION:A red photodetection area 2, green photodetection area 3, and blue photodetection area 4 are formed in the semiconductor substrate, and the respective photodetection areas and Si substrate 1 are convered with a protection film 7. The protection film 7 is coated with photosensitive resin which is obtained by sensitizing gelatine with ammonium dichromate, and the surface is exposed to light through a chromium mask pattern to form a pattern corresponding to the photodetection area 2 for red color by hot-water development of 40 deg.C; and then a heat treatment is performed at 150-200 deg.C and dyeing is carried out with red dye to form a red color filter 18. A color mixture preventing and protecting layer 5 is formed thereupon and then similar operation is repeated to form a green color filter 9 corresponding to the photodetection area 3 and a blue color filter 10 corresponding to the photodetection area 4. Consequently, the hard-to-peel color filter for a solid-state image pickup element is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a color filter for a color solid-state image sensor.

[Background of the invention]

Recently, with the spread of industrial and household VTRs,
Demand for small, lightweight, and easy-to-use television cameras is increasing. Therefore, semiconductor integrated circuits (generally IC or S
In a solid-state television camera using I), the face plate and electron beam generating portion of a conventional image pickup tube are replaced with an IC board, making it an independent solid-state image sensor. Because it does not use an electron beam, it is superior to an image pickup tube in terms of stability, low power consumption, and ease of handling, and is expected to become the next generation television camera.

This solid-state image sensor is formed in layers and consists of a semiconductor substrate part and a color filter part (Japanese Patent Application Laid-open No. 53
-47224). The above color filter is.

Generally, a dyeing medium such as a gelatin film containing a sensitizer is applied onto a semiconductor substrate equipped with a predetermined circuit, which is exposed to light using a mask, developed, and then dyed to obtain a predetermined color. - Form a filter pattern. Other colors/
When forming a filter, a color mixing prevention protective film made of a non-dyed polymer resin is further coated, a gelatin film for the second color 1 is applied, and the above steps are repeated. Form a filter pattern. Conventionally, filter patterns formed in this manner have had the disadvantage of being easy to peel off.

[Purpose of the invention]

The purpose of the present invention is to provide color and
An object of the present invention is to obtain a method for manufacturing a filter.

[Summary of the invention]

According to experiments conducted by the present inventors, although the dyeing ability is slightly reduced by dyeing the dyeing medium after heat treatment, there is no practical problem, and heat treatment increases the adhesion between the dyeing medium pattern and the substrate. It was found that the dyeing medium pattern no longer peeled off, and that the dyeing medium pattern in a swollen state contracted due to heat treatment and a good shape was formed.

Since the gelatin used as the dyeing medium decomposes above about 220°C and undergoes some deterioration above about 200°C, the upper limit of the temperature range for the above heat treatment must be particularly strictly observed.

In order to achieve the above object, the method for manufacturing a color filter according to the present invention involves coating a gelatin layer on a semiconductor substrate having a light-receiving part of a solid-state image sensor, exposing it to light through a mask pattern, and developing it. [Embodiments of the Invention] Color filters are obtained by heat treatment at a temperature between 150 and 200°C, more preferably between 180 and 200°C, and then dyed. 1 FIG. 1 is a cross-sectional view of the main parts of a solid-state imaging device according to the present invention. A light receiving region 2 for red, a light receiving region 3 for green, and a light receiving region 4 for blue are formed on the semiconductor substrate. Above light receiving area 2.3.4 and S] Substrate 1
is covered with a protective film 7.

A photosensitive resin weighted with gelatin and sensitized with z + ammonium acid acid is coated on the protective film 7 to a thickness of 17 μm, exposed through a chrome mask pattern, and developed for red color by hot water development with lIO'C. A pattern corresponding to region 2 was formed, and then heat treated at 180° C. for 30 minutes and dyed with red dye to form a red color filter 8. After forming the color mixing prevention preservation layer 5 thereon, the same operations as above are repeated to form a green color filter 9 corresponding to the light receiving area 3 for green and a light receiving area 4 for blue. A blue color filter 10 was formed accordingly to form a three-color laminated primary color filter. As a result, a satisfactory color filter with no pattern peeling was obtained.

Example 2 A protective film was formed using an organic substance on a solid-state image sensor substrate in the same manner as in Example 1, and a gelatin pattern with a thickness of 0.7 μm was formed thereon. Then 3 at 200'C
After heat treatment for 0 minutes, the gelatin was dyed with cyan acidic dye. As a result, a film was obtained that had good spectral characteristics as a color filter for the solid-state image sensor 7 and did not peel off.

[Effects of the Invention] As described above, the method for manufacturing a color filter according to the present invention includes coating a gelatin layer on a semiconductor substrate having a light-receiving part of a solid-state image sensor, exposing it to light through a mask, and
After development, it is heat treated at a temperature between 150 and 200°C, more preferably at a temperature between 180 and 200°C, and then dyed. - By using a filter, it is possible to obtain a color filter for a solid-state image sensor that is difficult to peel off.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a solid-state image sensing device according to the present invention. ■...81 Substrate 2... Light receiving area for red color 3... Light receiving area for green color 4...- Light receiving area for blue color 7... Protective film 8... Red color filter 9 ...Green color filter 10...Blue color filter Patent attorney Junnosuke NakatoshiContinued from page 10 Inventor Ken Tsutsui l Pi@Inventor Toshiaki Hashimoto1 Pi0 Inventor Akira Sasa Akira No [BI0 Inventor Akira Izumi I 1-28 Higashi-Koigakubo, Bunji City Hitachi, Ltd. Central Research Laboratory 1-28 Higashi-Koigakubo, Kokubunji City Hitachi, Ltd. Central Research Laboratory 1-28 Higashi-Koigakubo, Kokubunji City, Hitachi, Ltd. @ Inside Nakatomo Research Institute, Hitachi, Ltd.

Claims (1)

[Claims] After coating a gelatin layer on a semiconductor substrate having a light-receiving part of a solid-state image sensor, exposing it to light through a mask pattern, and developing it, the gelatin layer is heated to a temperature between 150 and 200°C, more preferably up to 180 or 6200°C. A method for manufacturing color filters, which is heat treated at a temperature between 1 and 2 and then dyed.