JPH03180802A - Manufacture of color filter - Google Patents

Abstract

PURPOSE: To avoid scattering of light and to improve transmittance for light by forming a color filter layer on the whole base body, forming a dyed layer, removing an intermediate layer and forming a protective layer to obtain a same height of the dyed layer. CONSTITUTION: A flattening layer 37 is formed on a silicon substrate 31 and a color filter layer 38 is formed all over the layer 37. The color filter layer 38 on a first photodiode 32 is exposed to form a first intermediate layer 39. A dyeing material to form a first dye layer 41 such as magenta color is applied on the part of the filter layer 38 exposed, and then the whole layer is irradiated and developed to remove the intermediate layer 39. Then cyan and yellow dyes to form second and third dye layers 45, 49 are applied on the second and third photodiodes 33, 34 by the same method. Then a protective film 51 is formed thereon. By this method, the dye layers are formed into same height, which prevents scattering of light. Since the intermediate layer is removed, the transmittance for light of the filter is increased.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a method for manufacturing a color filter used in solid-state image sensors and display devices, and in particular to a method for reducing scattering phenomena caused by diffraction and reflection of incident light. The present invention relates to a method of manufacturing a color filter that improves light transmittance.

[Conventional technology]

Colorization of solid-state imaging devices, which have recently been in the spotlight as imaging electron tubes and next-generation imaging devices that can replace electron tubes, is achieved by forming a color filter above a photoelectric conversion region. Furthermore, display elements such as liquid crystal display elements are colored by forming a color filter above the electro-optical conversion region.

Types of color filters include organic filters that dye organic substances such as gelatin, and inorganic filters that utilize optical interference. Among the above filters, organic filters are cheaper and are used more often than inorganic filters.

1A to 1C show conventional charge-coupled devices (Char
ge Coupled Device; Hereinafter referred to as CCD
FIG. 2 is a cross-sectional view showing the manufacturing process of a color filter for a color filter (referred to as ``color filter''), and the manufacturing process will be briefly described.

Referring to FIG. 1A, a semiconductor substrate vi has a surface having an uneven structure, photodiode arrays 2 and 34 are formed on the surface of the concave portion, and a conductive film 5 and an insulating film 6 are formed on the surface of the convex portion. , 1.

A flattening layer 7 made of a transparent material such as polyimide is coated on the surface of the semiconductor substrate l. Thereafter, a photosensitive material such as casein or gelatin is coated on the flattened N7, and a color filter pattern 8 is formed by a photographic method. Then, a dyeing material is applied to the flattening layer 7 and the color filter pattern 8. As shown in FIG.

At this time, only the color filter pattern 8 is dyed to form a dyed layer 9, and the dyed material on the flattening layer 7 is removed with deionized water.

The dyeing layer 9 has magenta, cyan (
In order to spectralize any one of colored light such as cyan and yellow, the light is dyed with one of magenta, cyan, yellow, etc., respectively.

Referring to FIG. 1B, polyimide is coated on the surface of the structure described above to form an intermediate layer 11. Referring to FIG. Subsequently, a color filter pattern 13 and a dye layer 15 are formed on the intermediate layer 11 in the same manner as described above so as to correspond to the photodiode 3. When forming the dyed layer 15, the intermediate layer 11 prevents the dyed layer 9 on which the dyed material is formed from being dyed.

Referring to FIG. 1C, an intermediate layer 17 is formed on the surface of the structure described above in the same manner as described above, and a desired color light is spectralized on a color filter layer 19 corresponding to the photodiode 4 and on the color filter layer 19. Dyeing layer 2 for
form 1.

Next, polyimide is applied to form a protective film layer 23, and an opening 25 for forming an electrode is formed to expose a portion of the conductive film, that is, the pad region.

In addition, other conventional color filters are disclosed in Korean Patent Publication No. 8.
No. 3-1454.

[Problem to be solved by the invention]

In the conventional color filter described above, the color filter layers corresponding to the photoelectric element array are formed at different heights, and the intermediate layer is stacked to increase the thickness. There were problems in that the image quality was poor due to a decrease in light transmittance due to the intermediate layer and the like, and it was difficult to form an opening for shaping the bottom of the electrode.

Therefore, an object of the present invention is to provide a method for manufacturing a color filter that can solve the above-mentioned problems and provide good image quality.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a base material with at least two color filters having different spectral characteristics, each corresponding to a plurality of pixels arranged in an IJ hook shape. In the manufacturing method, a first step of forming a color filter layer on the entire surface of the base material, and a second step of forming at least two or more different dyed layers on the surface of the color filter layer corresponding to each of the pixels. and,
The present invention is characterized by comprising a third step of forming a protective lj film layer, which is a light-transmitting material, on the entire surface of the color filter layer and the dyed layer.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 2A to 2D are cross-sectional views showing the manufacturing process for applying the color filter according to the present invention to a CCD.

However, it should be noted that the color filter according to the present invention can be applied to other solid-state imaging devices and display devices.

Referring to FIG. 2A, the surface of the silicon substrate 31 has an uneven structure, and a photodiode array 3 is formed on the surface of the recesses.
2.33.34, a wiring conductive film 35 made of metal such as M and an insulating film 36 made of Si 02 are formed on the convex portion.

A flattening layer 3 for flattening the surface on the silicon substrate 31
form 7. The flattening layer 37 is made of polyimide, and is coated to a thickness of about 3000 Å with the convex portions as a reference, so as to transmit 95% or more of incident light.

Next, the surface of the flattening layer 37 is dipped in casein or gelatin mixed with dichromic acid to a thickness of about 7,000 to form a color filter layer 38, and a photosensitive resin is coated on the color filter layer. After coating a certain polyimide to a thickness of about 1 μm, the color filter layer 38 on the first photodiode 32 is exposed using a photographic method, and the first photodiode 32 is exposed.
An intermediate layer 39 is formed.

Next, a dyeing material is applied to the exposed portion of the color filter layer 38 and the surface of the first intermediate layer 39. At this time, the above color filter F! The exposed surface of 3B reacts with the dyeing substance and becomes the first dyed layer 41. Thereafter, the dyeing material on the first intermediate layer 39 is removed with deionized water.

The above dyeing substance is magenta 1. In order to separate any one of color light such as cyan and yellow, it is necessary to select one of magenta, cyan, yellow, etc.
Use one.

In other words, the first dyeing layer 41 uses magenta as a dyeing substance in order to separate magenta light. Referring to Figure 2B, you can either develop after irradiating the entire surface or use a diluent (T
stripper) or stripper
The first intermediate layer 39 is removed using a method.

Next, the color filter layer 38 and the first dye layer 41
After applying polyimide to a thickness of about 1 μm on the upper portion of the photodiode 33, the color filter layer 38 on the second photodiode 33 is exposed using a photographic method to form a second intermediate layer 43.

Next, when a dyeing material is applied to the exposed portion of the color filter layer 38 and the surface of the second intermediate layer 43, the exposed surface of the color filter layer 38 reacts with the dyeing material and is dyed with the second intermediate layer 43. This becomes layer 45.

In order for the second dyeing layer 45 to disperse cyan light, cyan is used as a dyeing substance. At this time, the second intermediate layer 43 prevents the dyeing material for forming the second dyeing layer 45 from being dyed onto the first dyeing layer 541 and mixing colors. Thereafter, the dye material on the second intermediate layer 43 is removed in the same manner as described above.

Referring to FIG. 2C, the second intermediate layer 43 is removed in the same manner as the first intermediate layer 39. Thereafter, a third intermediate layer 47 and a third dyed layer 49 are formed using the same method as described above.

At this time, the third dyeing layer 49 is connected to the third photodiode 34.
It will correspond to Further, in order for the third dye layer 49 to separate yellow light, yellow is used as the dye material. Next, the dyed material on the third intermediate layer 47 is removed by the method described above.

Referring to FIG. 2D, the third intermediate layer 47 is
After removing the intermediate layers 39 and 43 using the same method, a protective film layer 51 is applied by applying polyimide to a thickness of about 0.5 to 1 μm over the entire surface of the structure described above. Thereafter, an opening 53 for forming an electrode is formed to expose a portion of the pad 35.

〔Effect of the invention〕

As described above, since the dyed layer and the like corresponding to the photoelectric element array are located at the same height, scattering phenomena due to refraction and reflection of the injected light can be prevented. Furthermore, since the intermediate layer for preventing color mixing is removed when applying the dyeing material, the light transmittance is improved and the opening process for forming the electrodes is facilitated.

Therefore, the present invention has the advantage of improving the light transmittance and preventing the scattering phenomenon due to diffraction and reflection of incident light, improving the image quality on the color filter, and facilitating the manufacturing process.

[Brief explanation of drawings]

1A to 1C are cross-sectional views showing the manufacturing process of a conventional color filter, and FIGS. 2A to 2D are cross-sectional views showing the manufacturing process of a color filter according to the present invention. 31: Semiconductor substrate 32: First photodiode 33: Second photodiode 34: Third photodiode 35: Conductive film or pad 36: Insulating film 37: Flattening layer 38: Color filter layer 39: First intermediate layer 41; First dyeing layer 43: second intermediate N4
5; Second dyed layer 47: Third intermediate layer 49 Third dyed layer 1 Protective film layer 3 Two openings

Claims (1)

[Claims] 1. A method for producing a color filter having at least two different spectral characteristics, each corresponding to a plurality of pixels arranged in a matrix shape on a base material, wherein: a first step of forming a color filter layer; a second step of forming at least two or more different dyed layers on the surface of the color filter layer corresponding to each pixel; and a step of forming a color filter layer and a dyed layer. A method for manufacturing a color filter, comprising a third step of forming a protective film layer that is a transparent material over the entire surface. 2. The method of manufacturing a color filter according to claim 1, further comprising the step of forming a flattening layer, which is a light-transmitting material, on the entire surface of the base material for flattening the entire surface of the base material. 3. The second step includes a first step of forming an intermediate layer on the entire surface of the color filter layer, and a second step of forming a group of openings corresponding to one group of pixels among the plurality of pixels in the intermediate layer. The third step of dyeing the color filter layer exposed by the one group of apertures with a predetermined substance and the fourth step of removing the intermediate layer are sequentially repeated at least twice, and the next aperture group is 2. The method of manufacturing a color filter according to claim 1, wherein the aperture group is dyed with a substance different from the previous aperture group so as not to overlap with the previous aperture group. 4. The method of manufacturing a color filter according to claim 3, wherein the color filter layer is formed of one of casein and gelatin mixed with dichromic acid. 5. The method of manufacturing a color filter according to claim 4, wherein the intermediate layer is formed of a photosensitive resin. 6. The method for manufacturing a color filter according to claim 5, wherein the intermediate layer is developed and removed after the entire surface is irradiated. 7. The method for producing a color filter according to claim 5, characterized in that the intermediate layer is removed using one of a diluent and a release agent. 8. The method of manufacturing a color filter according to claim 1, wherein the dyed layer is formed by dyeing magenta, cyan, and yellow. 9. The method of manufacturing a color filter according to claim 8, wherein the dyed layer is formed by dyeing magenta, cyan, and yellow as dyes. 10. In a method for manufacturing a color filter for a solid-state image sensor in which a plurality of pixels made of photoelectric conversion elements are integrated in a matrix shape on a semiconductor substrate, a light-transmitting material for flattening the entire surface of the semiconductor substrate is used. a first step of forming a certain flattening layer; a second step of forming a color filter layer on the entire surface of the flattening layer; and a second step of forming a color filter layer on the surface of the color filter layer corresponding to each of the pixels. A method for manufacturing a color filter, comprising: a third step of forming different dyed layers; and a fourth step of forming a protective film layer, which is a transparent material, on the entire surface of the color filter layer and the dyed layer. . 11. The third step includes a first step of forming an intermediate layer on the entire surface of the color filter layer, and a second step of forming a group of openings corresponding to one group of pixels among the plurality of pixels in the intermediate layer. A third step of dyeing the color filter layer exposed by the group of openings with a predetermined substance and a fourth step of removing the intermediate layer are sequentially repeated at least twice or more. Item 10. The method for producing a color filter according to item 10. 12. The method of manufacturing a color filter according to claim 11, wherein the color filter layer is formed of one of casein and gelatin mixed with dichromic acid. 13. The method for manufacturing a color filter according to claim 11, wherein the intermediate layer is formed of a photosensitive resin. 14. The method for producing a color filter according to claim 10, wherein the intermediate layer is removed by development after irradiating the entire surface. 15. The method for producing a color filter according to claim 3, wherein the intermediate layer is removed using one of a diluent and a release agent. 16. The method for manufacturing a color filter according to claim 10, wherein the dyed layer is formed by dyeing magenta, cyan, and yellow. 17. The method of manufacturing a color filter according to claim 16, wherein the dyed layer is formed by dyeing magenta, cyan, and yellow as dyes.