JP2007034137A - Method for manufacturing color filter substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a color filter substrate by simply correcting a black matrix exposure pattern, fabricating an exposure mask and forming a black matrix in a black matrix forming process in which a series of patterning treatments such as pattern exposure with a proximity exposure method on a black photosensitive resin layer on a transparent substrate, a development treatment and so on are conducted. <P>SOLUTION: The color filter substrate 100 is fabricated by forming the black matrix 21a on the transparent substrate 11 by using the exposure mask having a corrected pattern width of the black matrix adjacent to a specified position, and further by forming coloring color filter layers 30 composed of a red color filter 31R, a green color filter 31G, and a blue color filter 31B. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a color filter, and more particularly to a method for manufacturing a color filter substrate corresponding to thinning of a black matrix of 6 μm or less.

In recent years, with the increase in large color televisions, notebook computers, and portable electronic devices, there has been a remarkable increase in demand for liquid crystal displays, particularly color liquid crystal display panels.
In general, the most widely used liquid crystal cell driving method in liquid crystal display panels is a vertical electric field driving type using a TN (twisted nematic) method and an STN (super twisted nematic) method. Development of a liquid crystal cell driving system by IPS) is also in progress.

  A color filter substrate used in a color liquid crystal display panel is a transparent substrate in which a colored filter layer and a transparent electrode layer composed of a black matrix, a red filter, a green filter, and a blue filter are formed. In a color filter substrate, a colored filter layer made of a black matrix, a red filter, a green filter, a blue filter, a transparent electrode, and the like are formed on a transparent substrate through various processes using photolithography.

A method for manufacturing the color filter substrate will be described below.
1A to 1F are partial schematic cross-sectional views illustrating an example of a method for manufacturing a color filter substrate.
First, a black photosensitive resin in which carbon black is dispersed in an acrylic resin is applied on a transparent substrate 11 with a spinner to form a black photosensitive resin layer 21 (see FIG. 1A), pattern exposure, and development. The black matrix 21a is formed by performing a patterning process such as (see FIG. 1B).

  Next, a red photosensitive resin solution in which a red pigment (for example, a dianthraquinone pigment) is dispersed in an acrylic photosensitive resin is applied onto a transparent substrate on which the black matrix 21a is formed using a spinner, and the red photosensitive resin is applied. A resin layer is formed, and a series of patterning processes such as pattern exposure and development are performed using a predetermined exposure mask to form a red filter 31R (see FIG. 1C).

  Next, a green photosensitive resin solution in which a green pigment (for example, phthalocyanine green pigment) is dispersed in an acrylic photosensitive resin is applied onto a transparent substrate on which the black matrix 21a and the red filter 31R are formed using a spinner. Then, a green photosensitive resin layer is formed, and a series of patterning processes such as pattern exposure and development are performed using a predetermined exposure mask to form a green filter 31G (see FIG. 1D).

  Next, a blue photosensitive resin solution in which a blue pigment (for example, phthalocyanine blue pigment) is dispersed in an acrylic photosensitive resin is applied to a transparent substrate on which the black matrix 21a, the red filter 31R, and the green filter 31G are formed. A transparent substrate on which a blue photosensitive resin layer is formed, a blue pattern 31B is formed by performing a series of patterning processes such as exposure and development using a predetermined exposure mask, and a black matrix 21a is formed. A color filter is formed in which a predetermined number of colored filter layers 30 composed of a red filter 31R, a green filter 31G, and a green filter 31B are arranged (see FIG. 1E).

  Next, an indium tin oxide alloy target is sputtered to form the transparent electrode 41 on the black matrix 21a, the red filter 31R, the green filter 31G, and the green filter 31B on the transparent substrate 11, thereby obtaining a color filter substrate. (See FIG. 1 (f)).

In the pattern exposure process of the color filter substrate manufacturing process, a proximity exposure method (proximity) is employed in order to prevent occurrence of common defects during pattern exposure and to improve throughput.
For this reason, if an exposure area of a certain size is added to a part of a pattern having a certain width, the pattern width having a certain width at the end of the added exposure area is set to a pattern width other than the added exposure area. The phenomenon is different.

This will be specifically described below.
FIG. 6 shows an example of an exposure mask used when forming a black matrix, and FIG. 7 shows an example of a black matrix substrate.
The exposure mask 50g has a black matrix exposure pattern 52 composed of a light shielding region 51 and a transmission region, and an opening region 53d of a predetermined size formed adjacent to the black matrix exposure pattern 52 on a transparent substrate (see FIG. 6). ).
The black matrix substrate 60g forms a black photosensitive resin layer on the transparent substrate 11, pattern exposure is performed by proximity exposure (proximity) using the exposure mask 50g, and patterning processing such as development is performed. A black matrix 21a and a black region 21c are formed on a transparent substrate 11 (see FIG. 3A).
7A is a schematic plan view of the black matrix substrate 60g, and FIG. 7B is a schematic cross-sectional view of the schematic plan view of FIG. 7A taken along line AA ′. FIG. 7C is a schematic cross-sectional view of the schematic plan view of FIG. 7A cut along the line BB ′.

  FIG. 8 shows a schematic plan view in which the portion C of the schematic plan view of FIG.

When the line width of the black matrix 21a is w, the end of the black matrix 21a to which the black region 21c is added is thinner than the line width w of the black matrix 21a by δw.
This is because when an opening region 53d having a predetermined size is formed in a state adjacent to the black matrix exposure pattern 52 having a narrow line width, the exposure light gathers in the adjacent opening region 53d, and the light intensity is relatively low. It is estimated that the main factor is that the portion can be formed at the end of the adjacent black matrix exposure pattern 52.

In recent color filter substrates, the line width of the black matrix 21a is about 6 μm due to the trend toward higher density and higher definition, and the line width displacement amount δw of the black matrix 21a is about 0.5 to 2 μm.
When such a thin line width of the black matrix 21a occurs, defects such as white spots occur in the colored filter layer forming step.
FIG. 9A is a schematic plan view of the color filter substrate 100a in which the red filter 31R, the green filter 31G, and the green filter 31B are formed between the black matrixes 21a through the color filter forming process, and FIG. 9A is a schematic configuration sectional view obtained by cutting the schematic plan view of FIG. 9A along the line AA ′, and FIG. 10 is an enlarged schematic plan view of part C of the schematic plan view of FIG. 9A. .
In the color filter substrate 100a shown in FIGS. 9 and 10, the color filter is formed in a state where δw is thinned at the end of the black matrix 21a adjacent to the black region 21c, and the misalignment occurs in the green filter 31G forming process. And the amount of overlap between the right end of the green filter 31G and the black matrix 21a is small, and white spots are generated between the right end of the green filter 31G and the black matrix 21a in which the line width of δw is reduced. .

The state where the white spots have occurred is specifically described.
If the line width of the black matrix 21a is 6 μm, the overlap amount of each color filter is 3 μm in calculation, but in actuality, due to thermal expansion of glass, variation in transfer accuracy, etc., each color filter and the black matrix 21a The overlap margin amount is 3 μm or less.
Under such circumstances, the black matrix 21a adjacent to the black region 21c has a line width narrowing with a displacement amount δw of 1.5 μm, and the amount of overlap between the right end of the green filter 31G and the black matrix 21a is 0. Assuming that the green filter 31G is formed at 5 μm, in the region where the line width narrowing δw of 1.5 μm is generated in the black matrix 21a, white spots of about 1.0 μm are generated.

  As described above, when the line width narrowing δw of 1 μm or more occurs in the black matrix 21a, the overlap margin amount between each color filter and the black matrix 21a decreases, and the black matrix 21a in the region where the line width narrowing δw occurs is reduced. Is a problem because the probability of occurrence of white spots is increased and defects of the color filter substrate are generated.

In order to correct the exposure mask pattern of the black matrix 21a, a plurality of evaluation points are arranged along the outer periphery of the design pattern, and the transfer obtained using the exposure mask of the design pattern to which the evaluation points are attached. There has been proposed a method of correcting an exposure mask pattern by simulating an image, comparing the difference between the simulated transfer image and a previously designed pattern for each evaluation point (see, for example, Patent Document 1). .
However, with this method, the number of data is considerable, and it is not necessarily the best method for pattern correction of the exposure mask.
JP-A-9-034095

  The present invention has been devised in view of the above problems. A black photosensitive resin layer on a transparent substrate is subjected to pattern exposure by a proximity exposure method (proximity), and a series of patterning processes such as a development process are performed to obtain black. It is an object of the present invention to provide a method of manufacturing a color filter substrate in which a black matrix exposure pattern is formed by performing pattern correction of a black matrix exposure pattern in a simple manner to form an exposure mask.

  In order to achieve the above object in the present invention, first, in claim 1, at least a black photosensitive resin layer is subjected to patterning treatment such as pattern exposure and development on a transparent substrate to form a black matrix. In a method for producing a color filter substrate, including a step, a colored filter layer forming step of performing a patterning process such as pattern exposure and development on the colored photosensitive resin layer to form a plurality of colored filter layers, and a transparent electrode forming step, The color filter substrate manufacturing method is characterized in that a pattern width of a black matrix exposure pattern adjacent to a specific portion of an exposure mask used for pattern exposure in the black matrix forming step is corrected.

Further, in claim 2, the specific part is a part in which a transmission region of a predetermined size is formed adjacent to a predetermined position of the black matrix exposure pattern, and δhμm is added above and below the specific part, 2. The color filter substrate manufacturing method according to claim 1, wherein a pattern width of a black matrix exposure pattern adjacent to the specific portion is corrected.

  Furthermore, in claim 3, correction of the pattern width of the black matrix exposure pattern is correction for increasing the pattern width so as to eliminate the thinning of the line width of the black matrix. This is a method for manufacturing a color filter substrate.

  According to the method for manufacturing a color filter substrate of the present invention, a black matrix is formed by forming a black matrix using an exposure mask in which the pattern width of a black matrix adjacent to a specific portion is corrected, and forming a colored filter layer. A matrix can be formed, and as a result, a color filter substrate free from defects such as white spots can be manufactured.

Hereinafter, embodiments of the present invention will be described.
As shown in FIGS. 1 (a) to 1 (f), the method for producing a color filter substrate according to the first to third aspects of the present invention starts with black photosensitive in which carbon black is dispersed in an acrylic resin on a transparent substrate 11. The photosensitive resin solution is applied with a spinner or the like and dried to form the black photosensitive resin layer 21 (see FIG. 1A).
Here, as the transparent substrate 11, a glass substrate such as low expansion glass, non-alkali glass, or quartz glass, a plastic film, or the like can be used.

Next, pattern exposure is performed by proximity exposure (proximity) using a pattern-corrected exposure mask, and a series of patterning processes such as development are performed to form a black matrix 21a at a predetermined position on the transparent substrate 11. (See FIG. 1 (b)).
Here, a black matrix shape reproduction in the case where a black matrix is formed on the transparent substrate 11 by performing pattern exposure by proximity exposure (proximity) and performing a series of patterning processes such as development will be described.

  2A to 2C show an example of an exposure mask using a black matrix exposure pattern without pattern correction, and FIGS. 3A to 3C show pattern exposure using an exposure mask without pattern correction. Then, a series of patterning processes such as development are performed, and an example of the obtained black matrix substrate is shown in FIGS. 4A to 4C. FIGS. (A) to (c) show an example of a black matrix substrate produced by performing pattern exposure using a pattern-corrected exposure mask and performing a series of patterning processes such as development.

The exposure mask 50a shown in FIG. 2A is formed in a state where a black matrix exposure pattern 52 composed of a light shielding layer 51 and a transmission region, and a specific portion 53a composed of a transmission region are adjacent to predetermined positions of the black matrix exposure pattern 52. Is.
The exposure mask 50b shown in FIG. 2B is formed with a black matrix exposure pattern 52 composed of a light shielding layer 51 and a transmission region, and a specific portion 53b composed of a transmission region adjacent to a predetermined position of the black matrix exposure pattern 52. Is.
An exposure mask 50c shown in FIG. 2C is formed in a state where a black matrix exposure pattern 52 including a light shielding layer 51 and a transmission region, and a specific portion 53c including a transmission region are adjacent to predetermined positions of the black matrix exposure pattern 52. Is.

Here, as a result of performing a series of patterning processes such as development on the transparent substrate 11 on which the black photosensitive resin layer 21 is formed using the exposure mask 50a by the proximity exposure method (proximity) and performing a specific patterning process. A black matrix substrate 60a is obtained in which the end of the black matrix 21a adjacent to the specific black region 21b formed by exposing the portion 53a is narrowed by δB (see FIG. 3A).
Similarly, when the exposure mask 50b is used, a black matrix substrate 60b in which the end of the black matrix 21a adjacent to the specific black region 21b formed by exposing the specific portion 53b is narrowed by δB is obtained (FIG. 3 ( b)).
Similarly, when the exposure mask 50c is used, a black matrix substrate 60c is obtained in which the end of the black matrix 21a adjacent to the specific black region 21b formed by exposing the specific portion 53c is narrowed by δB (FIG. 3 ( c)).
The thinning amount δB at the end of the black matrix 21a adjacent to the specific black region 21b varies depending on the size of the specific portion when an exposure mask having a black matrix exposure pattern with a line width of 6 μm is used, but is 100 to 180 μm. When the pattern exposure is performed by the proximity exposure method (proximity) of the exposure gap and the patterning process such as development is performed, the thickness becomes 0.5 to 2 μm.

As described above, when pattern exposure is performed using the exposure masks 50a, 50b, and 50c in which the specific portions 53a, 53b, and 53c including the transmission region are formed on the black matrix exposure pattern 52 including the transmission region, the black matrix exposure pattern 52 is adjacent to the specific black region 21b. It has been found that the black matrix 21a has a shape whose end is narrowed by δB, and the present inventors have determined that the line width narrowing amount δB of the black matrix 21a adjacent to the specific black region 21b and the black matrix exposure pattern of the exposure mask. It has been found that the pattern correction of the black matrix exposure pattern adjacent to a specific part of the exposure mask can be easily performed by obtaining the relationship with the width.
Since the specific portion formed in the black matrix of the color filter substrate is constant within one base slope, the thinning amount δB at the end of the black matrix can be easily reflected in the pattern correction amount by pattern simulation.

4A to 4C show an example of pattern correction of a black matrix exposure pattern of an exposure mask. The exposure mask 50d shown in FIG. 4A is a black comprising a light shielding layer 51 and a transmission region. The matrix exposure pattern 52 and the black matrix exposure pattern 52 are configured by specific portions 53a made of a transmissive region at predetermined positions, and the black matrix exposure pattern 52 adjacent to the specific portion 53a made of the transmissive region is higher than the specific portion 53a. When the height is h, pattern correction is performed by protruding the displacement amount δw within a range obtained by adding the displacement amount δh above and below the specific portion 53a.
Here, the displacement amount δh is about 2 μm, and the displacement amount δw is 1 to 2 μm.

Similarly, in the exposure mask 50e shown in FIG. 4B, the black matrix exposure pattern 52 adjacent to the specific portion 53b made of the transmissive region has the upper and lower portions of the specific portion 53b when the height of the specific portion 53b is h. The pattern correction is performed by protruding the displacement amount δw within the range obtained by adding the displacement amount δh to the above.
Here, the displacement amount δh is about 2 μm, and the displacement amount δw is 1 to 2 μm.

Similarly, in the exposure mask 50f shown in FIG. 4B, the black matrix exposure pattern 52 adjacent to the specific portion 53c formed of the transmissive region has the upper and lower portions of the specific portion 53c when the height of the specific portion 53c is h. The pattern correction is performed by protruding the displacement amount δw within the range obtained by adding the displacement amount δh to the above.
Here, the displacement amount δh is about 2 μm, and the displacement amount δw is 1 to 2 μm.

FIGS. 5A to 5C show a proximity exposure method with an exposure gap of 100 to 180 μm using an exposure mask in which the black matrix exposure pattern 52 adjacent to the specific portions 53a, 53b and 53c is corrected. The black matrix 2 adjacent to the specific black region 21b subjected to pattern exposure by proximity) and subjected to a series of patterning processes such as development.
The shape reproduction state of 1a is shown.
The black matrix substrates 60a, 60b, and 60c exhibiting the shape reproducibility of the black matrix 21a adjacent to the specific black region 21b having a predetermined width (6 μm) are obtained.

  Next, a red photosensitive resin solution in which a color pigment (for example, dianthraquinone pigment) is dispersed in an acrylic photosensitive resin is applied onto the black matrix substrate 60 using a spinner to form a red photosensitive resin layer. Then, a series of patterning processes such as exposure and development are performed using a predetermined exposure mask to form a red color filter 31R (see FIG. 3C).

  Next, a green photosensitive resin solution in which a color pigment (for example, phthalocyanine green pigment) is dispersed in an acrylic photosensitive resin is applied onto the black matrix substrate 60 on which the red color filter 31R is formed using a spinner. A green photosensitive resin layer is formed, and a series of patterning processes such as pattern exposure and development are performed using a predetermined exposure mask to form a green color filter 31G (see FIG. 3D).

  Next, a black matrix substrate 60 in which a red color filter 31R and a green color filter 31G are formed by using a blue photosensitive resin solution in which a color pigment (for example, phthalocyanine blue pigment) is dispersed in an acrylic photosensitive resin, using a spinner. A blue photosensitive resin layer is formed by coating on the surface, and a series of patterning processes such as pattern exposure and development are performed using a predetermined exposure mask to form a blue color filter 31B, and a black matrix 21a is formed. A colored color filter layer 30 composed of a red color filter 31R, a green color filter 31G, and a green color filter 31B is formed on the transparent substrate 11 (see FIG. 3E).

  Next, an indium tin oxide alloy target is sputtered to form a transparent conductive film 41 having a predetermined thickness made of an indium tin oxide film on the red color filter 31R, the green color filter 31G, the green color filter 31B, and the transparent substrate 11. Then, the color filter substrate 100 is manufactured (see FIG. 3F).

  As described above, by performing pattern correction of the black matrix exposure pattern adjacent to the specific portion to produce a black matrix substrate and a color filter substrate, it is possible to eliminate the thinning of the black matrix adjacent to the specific black region, A color filter substrate without white spots can be obtained.

  Using a black matrix pattern in which the black matrix pattern 52 has a line width of 6 μm, a pitch of 150 μm, and a specific portion 53b of 20 × 30 μm, first, δw is set in a range obtained by adding δh = 2 μm above and below the specific portion 53b having a height of 30 μm. An exposure mask 50e having a black matrix pattern protruding by 1 μm was produced (see FIG. 4B).

  Next, a black photosensitive resin solution in which carbon black is dispersed in an acrylic resin is applied on a transparent substrate 11 made of AN100 glass using a spinner or the like, and dried to form a black photosensitive resin layer 21 having a thickness of 1.5 μm. (See FIG. 1 (a)).

Next, the exposure mask 50e is used to perform pattern exposure with a proximity exposure method (proximity) with an exposure gap of 100 μm, and a series of patterning processes such as development are performed, so that the black matrix 21a and the specific black region are formed on the transparent substrate 11. 21b was formed, and the black matrix substrate 60 was produced (refer FIG.1 (b) and FIG.5 (b)).
Here, the line width of the black matrix 21a adjacent to the specific black region 21b was 6 μm.

  Next, a red photosensitive resin solution in which a dianthraquinone pigment is dispersed in an acrylic photosensitive resin is applied onto the black matrix substrate 60 using a spinner to form a red photosensitive resin layer, and a predetermined exposure mask is formed. A series of patterning processes such as pattern exposure and development were performed to form a red color filter 31R (see FIG. 3C).

  Next, a green photosensitive resin layer in which a phthalocyanine green pigment is dispersed in an acrylic photosensitive resin is applied onto the black matrix substrate 60 on which the red color filter 31R is formed by using a spinner to form a green photosensitive resin layer. The green color filter 31G was formed by performing a series of patterning processes such as pattern exposure and development using a predetermined exposure mask (see FIG. 3D).

  Next, a blue photosensitive resin solution in which a phthalocyanine blue pigment is dispersed in an acrylic photosensitive resin is applied onto the black matrix substrate 60 on which the red color filter 31R and the green color filter 31G are formed using a spinner. A photosensitive resin layer is formed, and a series of patterning processes such as pattern exposure and development are performed using a predetermined exposure mask to form a blue color filter 31B, and a red color is formed on the transparent substrate 11 on which the black matrix 21a is formed. A colored color filter layer 30 composed of the color filter 31R, the green color filter 31G, and the green color filter 31B was formed (see FIG. 3E).

  Next, an indium tin oxide alloy target is sputtered to form a transparent conductive film 41 having a predetermined thickness made of an indium tin oxide film on the red color filter 31R, the green color filter 31G, the green color filter 31B, and the transparent substrate 11. Thus, a color filter substrate 100 was produced (see FIG. 3F).

(A)-(f) is typical structure sectional drawing which shows the process of the manufacturing method of the color filter substrate of this invention. (A)-(c) is a schematic plan view which shows an example of an exposure mask. (A)-(c) is a schematic plan view which shows an example of a black matrix substrate. (A)-(c) is a schematic plan view which shows an example of the exposure mask which carried out the pattern correction | amendment. (A)-(c) is a schematic plan view which shows an example of a black matrix substrate. It is a schematic plan view which shows an example of an exposure mask. (A) is a schematic plan view which shows an example of a black matrix substrate. (B) is a schematic cross-sectional view of a black matrix substrate obtained by cutting the schematic plan view of (a) along the line A-A ′. (C) is a schematic cross-sectional view of a black matrix substrate obtained by cutting the schematic plan view of (a) along the line B-B ′. It is the schematic top view to which the C section of the schematic top view of Fig.7 (a) was expanded. (A) is a schematic plan view which shows an example of a color filter substrate. (B) is a schematic cross-sectional view of a color filter substrate obtained by cutting the schematic plan view of (a) along the line A-A ′. It is the schematic top view to which the C section of the schematic top view of Fig.9 (a) was expanded.

Explanation of symbols

11 ... Transparent substrate 21 ... Black photosensitive resin layer 21a ... Black matrix 21b ... Specific black region 21c ... Black region 30 ... Colored color filter layer 31R ... Red filter 31G ... Green filter 31B ... Blue Filter 41... Transparent conductive film 50 a, 50 b, 50 c, 50 d, 50 e, 50 f, 50 g... Exposure mask 51. 60, 60a, 60b, 60c, 60d, 60e, 60f, 60g ... Black matrix substrate B ... Pattern width δB of black matrix exposure pattern ... Displacement amount h ... Height of specific portion δh ... Displacement amount w ... ... Line width of black matrix δw ... Displacement

Claims (3)

  At least a black photosensitive resin layer is subjected to patterning processing such as pattern exposure and development on a transparent substrate to form a black matrix, and a colored photosensitive resin layer is subjected to patterning processing such as pattern exposure and development. In a method for manufacturing a color filter substrate having a colored filter layer forming step for forming a plurality of colored filter layers and a transparent electrode forming step, black adjacent to a specific portion of an exposure mask used for pattern exposure in the black matrix forming step A method of manufacturing a color filter substrate, wherein a pattern width of a matrix exposure pattern is corrected.   The specific portion is a portion in which a transmission region of a predetermined size is formed adjacent to a predetermined position of a black matrix exposure pattern, and a black matrix adjacent to the specific portion within a range obtained by adding δhμm above and below the specific portion. 2. The method of manufacturing a color filter substrate according to claim 1, wherein the pattern width of the exposure pattern is corrected.   3. The method of manufacturing a color filter substrate according to claim 2, wherein the correction of the pattern width of the black matrix exposure pattern is correction for increasing a pattern width so as to eliminate a thin line width of the black matrix.

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