TW451488B - Method of manufacturing submicron color filter - Google Patents

Abstract

A method of manufacturing a submicron color filter consists of coating a substance layer with a blue photoresist and forming blue pixels by exposing and developing the blue photoresist once, then coating the layer with a green photoresist and forming green pixels by exposing and developing the green photoresist twice with each exposure covering 25% pattern ratio, and finally coating the layer with a red photoresist and forming red pixels by exposing and developing the red photoresist once.

Description

451488 '' '' V. Description of the invention (1) [Field of the invention] The present invention relates to a method for manufacturing a color filter, and in particular to a submicron of a four-day element configuration type. Manufacturing method of color filter. [Know-how] Color calenders are necessary materials for solid-state imaging devices (solid state imaging devices). Generally, a solid-state imaging device has a photodiode in a semiconductor silicon substrate as a sensor area, and a color filter is located above the photodiode. After the incident light passes through the color filter, it is filtered into three primary colors, red (R), green (G), and blue (B), and then absorbed and sensed by the corresponding photodiode. The manufacturing method of a conventional solid-state imaging device is shown below. FIG. 1 is a cross-sectional view showing a conventional solid-state imaging device. First, a photodiode 102 is formed in a semiconductor light emitting substrate 100, and each photodiode 102 has a corresponding transistor 104 for reading image data. After that, a transparent and planarized oxide layer 106 is covered over the transistor 104, and then a color filter 108 is formed on the planarized oxide layer 106. Continue to form another transparent and planarized oxide layer 11 0 over the color filter 108, and then form a microlens 112 on the planarized oxide layer 110. With the current trend of increasing the sensitivity and resolution of images and reducing costs, the process has moved from micrometers to the submicron era, so the pixel size must be reduced from 5 micrometers to less than 0.35 micrometers. But ’has made the technology of sub-micron color filters

451488_ V. Description of the invention (2) These problems will be explained in detail below in conjunction with Figures 2A to 2C. Figures 2A to 2C are top views showing the detailed manufacturing process of the color filter described above. The color filter j 〇8 of the solid-state imaging device is commonly used in a four-day pattern configuration, where the pattern ratio of red and blue (field rati〇) is 25¾, and the ratio of green pattern accounts for 50%. First, a layer of blue photoresist is coated on the oxide layer 06, and after exposure and development, the blue daylight B of the color filter is defined, as shown in FIG. 2A. Continue coating a layer of green photoresist on the oxide layer 106. After exposure and development, the green pixels G 'of the color filter are defined as shown in FIG. 2B. However, since the pattern ratio of the green pixel G accounts for 50%, during the exposure process, a pattern of holes 109 is exposed, and this hole 109 is used to place the red daylight R that will be formed later. However, for the definition of the pattern of holes 丨 09, the resolution is poor due to the phenomenon of dry shots. In addition to making the defined contour of the green daylight 6 poor, it is also easy to produce residues in the holes 109. — ', A red photoresist is coated on the oxide layer 106, and the red daylight R of the color filter is defined after exposure and development, as shown in FIG. 2C, because the outline of the hole 109 is smaller than the predetermined The size of the pixel, plus the residue of the green dipeptide G in the hole, will affect the performance of the red pixel R. [Objective and Summary of the Invention] In view of the problems faced when the size of the pixel is reduced, a method is provided. Method to improve the performance of sub-micron color filters. month

4 51 4B8 V. Description of the invention (3) In addition, the present invention provides a method for manufacturing a four-pixel configuration type sub-micron color light sheet, which can effectively reduce the possibility that green pixel residues remain in other non-green daylight regions. . In addition, the present invention provides a method for manufacturing a sub-micron color data sheet of the four-day-horizon configuration type, which can make the green day-horizon have a good profile. The present invention proposes improvements to the shortcomings of the above-mentioned conventional technology. The method for manufacturing a sub-micron color filter of the present invention includes: covering a layer of blue photoresist to form a blue pixel after an exposure and development process, and thereafter Cover a layer of green photoresist, and perform two exposure steps, and the pattern ratio of each exposure is 25%. 'Another development step is performed to form a green daylight, and finally a layer of red photoresist is covered. After an exposure and development process, a red daylight is formed The prime 'finishes the color filter. Among them, the process sequence of blue daylight and red daylight can also be reversed. The invention provides a method for manufacturing a sub-micron color roll and a light sheet applied to a solid-state image processing device. The method includes: forming an interconnect on a sensing area, covering a flat dielectric layer, and covering the layer with a blue layer. The color photoresist is formed into blue pixels after the exposure and development process, and then covered with a layer of green photoresist to perform two exposure processes. The pattern ratio of each exposure is 25 \ ', and then the development process is performed to form green daylight. Finally, it is covered with a layer of red color. After one exposure and development process, red pixels are formed, that is, the color phosphor film is completed. Among them, the process sequence of blue daylight and red daylight is relatively adjusted. Finally, the color filter is used. Another layer of flat dielectric is formed on the chip, and a microlens corresponding to the sensing area is formed thereon. According to a preferred embodiment of the present invention, the material of the above-mentioned red photoresist

Page 7 45M88 V. Description of the invention (4) It is a negative photoresist containing a red dye. The material of the green photoresist is a negative photoresist containing a green dye. The material of a blue photoresist is a negative photoresist containing a blue dye. By the above-mentioned method for improving the exposure quality, the pixel size can be reduced to 3 micrometers or more. In order to make the above-mentioned objects, features, and advantages of the present invention more comprehensible ', a preferred embodiment is given below, and in conjunction with the accompanying drawings, the detailed description is as follows: [Simplified description of the drawings] FIG. 1 is a drawing A cross-sectional view of a conventional solid-state imaging device. Figures 2A to 2C are top views showing the manufacturing process of a conventional color filter. FIG. 3 is a cross-sectional view of a solid-state imaging device according to a preferred embodiment of the present invention. Figures 4A to 4D are top views of the manufacturing process of the color filter of Figure 3. [Symbol description] 100 ~ semiconductor silicon substrate; 300 ~ substrate red daylight; B ~ blue daylight; G ~ green pixel; G2 ~ green daylight pattern 112, 340 ~ micro lens; 108,308 ~ color filter Light sheet; 102, 302 ~ photodiode; 104, 304 ~ transistor, 106,110 ~ oxide layer; 109 ~ hole; 306,316,326,336 ~ dielectric layer embodiment

4 5 1 48 g 5. Description of the invention (5) In the exposure process, the resolution of the holes is very different from the resolution of the blocks. Because the holes are prone to interference by the radiant phenomenon, the resolution of the holes is relatively high. difference. Therefore, the present invention avoids defining the pattern of holes in the manufacturing method of the sub-micron color light-reflective sheet of the four-day configuration type to improve the efficiency of the red, blue, and green pixels of the color filter. First, please refer to FIG. 3, which is a sectional view showing a solid-state imaging device according to the present invention. A photodiode 302 is formed in the substrate 300, and the photodiode 302 is a sensing area. Each photodiode 302 has its corresponding transistor 3004 'to read the charge data generated in the sensing area, and then convert it into an image through a series of circuit designs. After that, a transparent and flattened dielectric layer 306 is covered on top of the transistor 304, and the material is, for example, oxide. Then perform the interconnection process 'to form an interconnection structure above the dielectric layer 306. This interconnection structure can be a multiple interconnection structure or a single-layer interconnection structure' to make each component Electrical connection. In Figure 3A, the two-layer interconnect structure is taken as an example. The reference numerals 307a and 307b in the figure indicate the wires of the first and second layers, respectively, and the wires 30 7a and 307b A transparent dielectric layer 316 is used for electrical isolation. The material of the dielectric layer 316 is, for example, silicon oxide. Then, a transparent and planarized dielectric layer 326 is covered on the third layer of the conductive wire 307b, and the material is, for example, silicon oxide. Then, a blue-green-red color doped sheet 308 ′ is formed on the planarized dielectric layer 326. The detailed manufacturing process is as shown in the following figure. The layer color is:

451488, > 5. Description of the invention (6) (pigment) negative photoresist, and then performing an exposure process and a development process to 'harden the exposed blocks, so that this blue photoresist is turned into many block blue Color dipeptide B 'The pattern ratio of this blue dipeptide B is 25%. P then coats a layer of green photoresist on the dielectric layer 326. This green photoresist is a negative photoresist containing a green dye 'and will cover other areas of the blue daylight. Then, the first stage of the exposure process is performed to define a part of the green daylight pattern G1 ′ whose pattern ratio is 25% * as shown in FIG. 4B. Continue the second stage of the exposure process to define another part of the green daylight pattern G2, whose pattern ratio is also 25%, as shown in Figure 4C. After that, the development process is performed one time to harden the green daylight patterns G1 and G2, and then turn to green daylight G, as shown in FIG. 4D. Since the green daylight G is exposed to a block pattern twice during the exposure process, the formed green pixel G can have a good outline, so that the green daylight can be improved by using the existing color photoresist material. The correctness of the pattern of prime G. In addition, residues in non-green diurnal G regions were effectively reduced. A layer of color photoresist is then coated on the dielectric layer 326, such as a red photoresist, which is a negative photoresist containing a red dye, and undergoes an exposure seeding and a development process to turn the red photoresist into red. Days R, as shown in Figure 4D. It is worth noting that it is also possible to form the red lutein R first, and then sequentially form the green lutein G and the blue lutein B. Please continue to refer to FIG. 3, another transparent and planarized dielectric layer 336 is formed on the color filter 308, and the material is, for example, silicon oxide. Of course

451488 5. Description of the invention (7) A microlens 340 is formed on the planarized dielectric layer 336, and the microlens 340 corresponds to the photodiode 302. [Features and Effects of the Invention] In summary, the present invention has at least the following advantages: 1. The present invention forms green daylight by exposing the green photoresist twice and exposing it in a block pattern. 2. The manufacturing method of the sub-micron color filter of the four-pixel configuration type of the present invention can effectively reduce the residual of green pixels in other non-green daylight regions. 3. The method for manufacturing a sub-micron color filter of the four-day pigment configuration type according to the present invention can make the green color pigment have a good profile. 4. Each of the blue, green and red color elements of the sub-micron color filter of the four-day element configuration type of the present invention has a good separation. 5. The present invention can improve the accuracy of the green daylight pattern of the sub-micron color filter of the four day element configuration type using the existing green photoresist material, thereby saving the cost of developing new materials. 6. The process of the present invention is quite simple and is easily compatible with the current process. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention to "any person skilled in the art can be modified and retouched without departing from the spirit and scope of the present invention. The scope of protection shall be defined by the scope of the patent application attached after the event.

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Claims (1)

4514B8 " " _ 11 · VI. Patent Application ^ ^ '1. A method for manufacturing a sub-micron color filter, the manufacturing method includes the following steps: coating a first color photoresist on a material layer; ^ Performing a first exposure process and a first development process to convert the first color photoresist into a plurality of first color pixels; coating a green photoresist on the material layer; performing a second exposure process To define a part of the green daylight pattern; to perform a third exposure process to define another-part of the green daylight map tea, and to perform a second development process to form a plurality of green daylight elements; A second color photoresist is coated on the layer; and, a fourth exposure process and a third development process are performed to turn the second color photoresist into a plurality of second color photon e 2. if applying for a patent The manufacturing method according to item 1 of the scope, wherein the first color photoresist is a blue photoresist, the first color photon is a blue photon, the second color photoresist is a red photoresist, The two-color daylight is a red daylight. — 3. The manufacturing method as described in item 1 of the scope of patent application, wherein the first color photoresist is-a red photoresist 'the first color photon is a red photon' and the second color photoresist is a blue The color is bright and 'the second color daylight is a blue daylight. 4. The manufacturing method described in item 2 of the scope of patent application, wherein the red photoresistor is a negative photoresistor, the blue photoresistor is a negative photoresistor, and the green photoresistor is a negative photoresistor. Page 12 6. Scope of Patent Application Photoresist. 5. The manufacturing method according to item 3 of the scope of patent application, wherein the red photoresist is a negative photoresist, the blue photoresist is a negative photoresist, and the green photoresist is a negative photoresist. The method includes: manufacturing a sub-micron color filter on the substrate, providing a substrate, the substrate having a sensing region and a transistor for controlling the sensing region; covering the transistor with a A first dielectric layer for controlling the formation of an interconnect crystal on the first dielectric layer; forming a second interlayer coating on the interconnect structure to form a coating on the second dielectric layer A first exposure process and a first> color photoresist are performed, and the color photoresist is converted into a plurality of first color book processes, so that the first layer is coated with n on the second dielectric layer, and a first The second exposure process is to determine the plan; the definition-part of the green daytime picture part of the green daytime picture pattern to perform a third exposure process to define another second development process to make these green pixels; — 'The color pixel pattern is converted into a plurality of first coatings on the second dielectric layer for a fourth exposure process and a third resistance; and the color photoresist is converted into a plurality of second color daylight elements; To make the second I1H No. 13 X 451488 'Six, apply for a patent Forming a third dielectric layer on the first color, green, and second color daylight; and forming a microlens on the third dielectric layer. 7. The method according to item 6 of the scope of patent application, wherein the materials of the first dielectric layer, the second dielectric layer, and the third dielectric layer include silicon oxide. 8. The manufacturing method as described in item 6 of the scope of patent application, wherein the first color photoresist is a blue photoresist, the first color photon is a blue photon, and the second color photoresist is a red Photoresistance, the second colored daylight is a red daylight. 9. The manufacturing method as described in item 6 of the scope of patent application, wherein the first shadow color photoresist is a red photoresist, the first color daylight is a red daylight, and the second color photoresist is a blue light. The second color lutein is a blue lutein. 10. The manufacturing method as described in item 8 of the scope of the patent application, wherein the red photoresist is a negative photoresist, the blue photoresist is a negative photoresist, and the green photoresist is a negative photoresist. 11. The manufacturing method according to item 9 of the scope of patent application, wherein the red photoresist is a negative photoresist, the blue photoresist is a negative photoresist, and the green photoresist is a negative photoresist. Page 14