JP2005077986A - Color filter and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-quality color filter having a large area, which is easily manufactured. <P>SOLUTION: In the color filter, a first line 21 and a second line 22, which are arranged in an adjacently deviated manner, are provided and a shading section 24 is arranged at the boundary portion with a third line 23, which connects the lines 21 and 23 and has a wide line width, to vary the line width in a gradual manner. The shading section 24 is obtained by forming shading at the connecting portion of transfer patterns while maintaining a prescribed interval between a light shielding plate and a glass substrate during an exposure. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a color filter and a method for manufacturing the same, and more particularly to a color filter used in a large-screen color liquid crystal display device.

Conventionally, liquid crystal display devices with features such as thin, light weight and low power consumption have been widely used as flat panel displays, but with the application to TV and computer displays, color display has become mainstream, In recent years, an increase in screen size has been demanded.
Some color liquid crystal display devices use a color filter that converts light from a white light source into three primary colors of R, G, and B, and mixes these three primary colors to produce each color. As shown in FIG. 6, the color filter 1 has a structure in which each pixel 2 is divided into three sub-pixels 3r, 3g, and 3b composed of R, G, and B colored layers. A black matrix 4 that is a light shielding region is formed at a boundary portion of the pixel.

  For example, such a color filter is formed by forming a black matrix as a sub-pixel frame on a glass substrate through pattern transfer using a photomask, and then applying a pigment-dispersed resist to R, G, and B colored layers. It is manufactured by sequentially forming by pattern transfer and development.

In addition, with the increase in the size of the screen, a substrate having a larger area has been used as a glass substrate used for a color filter. However, since a high-precision photomask and exposure apparatus used for manufacturing color filters are required, it is extremely difficult to increase the size of the photomask and exposure apparatus in accordance with the increase in size of the substrate.
Therefore, for example, in Patent Document 1, as shown in FIG. 7A, the left half of the effective region 6 is exposed using a photomask 7 having an area that is almost half of the effective region 6 of the glass substrate 5. Thereafter, as shown in FIG. 7B, the left and right sides of the effective area 6 are exposed by moving the glass substrate 5 relative to the photomask 7 to the left and exposing the remaining right half of the effective area 6 with the same photomask 7. A method for producing a large area color filter by forming the exposed regions 8 and 9 is disclosed.

JP-A-8-45823

However, as shown in FIG. 7B, when a plurality of exposure regions 8 and 9 are connected to each other in a straight line, there is a problem that the connected portions appear clearly as unevenness and the quality as a color filter is deteriorated. .
Patent Document 1 also describes that the exposure regions 8 and 9 are exposed so that the light-shielding portions by the photomask 7 slightly overlap each other. However, a negative resist is used for simplifying the manufacturing process. In the case of forming a black matrix, the light shielding portions cannot be overlapped with each other in order to prevent the black matrix from being cut at the connection portions of the exposure regions, and it has been difficult to eliminate the connection unevenness.

The present invention has been made to solve such problems, and an object of the present invention is to provide a color filter that can be easily manufactured with high quality and a large area.
Another object of the present invention is to provide a color filter manufacturing method that can easily manufacture a high-quality, large-area color filter.

The color filter according to the present invention is a color filter in which a black matrix is formed in a predetermined pattern on a substrate and a plurality of colored layers are formed in an opening region of the black matrix. The first line, the second line having the same line width as the first line and arranged to be shifted from the first line, the first line and the second line, and the first line A third line having a wide line width, and further arranged at a boundary portion between the first line and the second line with the third line, and from the first line and the second line to the third line. It is equipped with a blur part that gently changes the line width to the line.
Preferably, each blur part has a length of 1 mm or more along the longitudinal direction of the first line and the second line.

The color filter manufacturing method according to the present invention includes a predetermined pattern on a substrate by connecting a transfer pattern by moving a photomask having an area smaller than the substrate relative to the substrate and performing exposure multiple times. In the manufacturing method of a color filter in which a black matrix is formed and a plurality of colored layers are formed in the opening area of the black matrix, a part of the opening portion of the photomask located at the joining portion of the transfer pattern is shielded by a light shielding plate Exposure is performed in a state where the photomask and the substrate are relatively moved so that the transfer patterns partially overlap each other, and a part of the opening portion of the photomask located at the joining portion is shielded by a light shielding plate The exposure of the transfer pattern is carried out by maintaining a predetermined distance between the light shielding plate and the substrate during exposure. It is a method of forming a blur calm alignment portion.
In addition, it is preferable to perform exposure with an exposure amount in a saturated region where the line width of the black matrix transferred onto the substrate hardly changes even when the exposure amount changes.

  As described above, according to the present invention, the black matrix has the first line having the predetermined line width and the second line having the same line width as the first line and being shifted from the first line. And a third line connecting the first line and the second line and having a wider line width than the first line, and a third line of the first line and the second line And a blur part that gently changes the line width from the first line and the second line to the third line, so that it is easy to manufacture with high quality and large area. A color filter that can be realized is realized.

  In addition, according to the color filter manufacturing method of the present invention, blurring is formed at the joining portion of the transfer pattern by maintaining a predetermined distance between the light shielding plate and the substrate during exposure, so that high quality and high quality can be achieved. An area color filter can be easily obtained.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 shows the arrangement of an exposure apparatus for carrying out the color filter manufacturing method according to the embodiment of the present invention. A mask suction stage 12 is disposed above the exposure stage 11, and a pair of light shielding plates 13 are disposed above the mask suction stage 12. The exposure stage 11 and the pair of light shielding plates 13 are each configured to be moved in the horizontal direction by a driving device (not shown). Further, a curved mirror 14 is disposed above the light shielding plate 13, and a UV lamp 15 serving as a light source is disposed facing the curved mirror 14.

  A glass substrate 16 used for a color filter is placed on the upper surface of the exposure stage 11. An opening 17 for passing UV light used for exposure is formed in the mask suction stage 12, and a photomask 18 is disposed under the opening 17. The photomask 18 is sucked and held on the lower surface of the mask suction stage 12 at the periphery of the opening 17. The photomask 18 has an area smaller than the glass substrate 16, for example, an area slightly larger than half of the effective area of the glass substrate 16, and corresponds to a peripheral frame portion and a repetitive pattern of a black matrix used for a color filter. It has an opening 19 having a predetermined pattern.

  Next, a method for manufacturing a color filter in this embodiment will be described. It is assumed that a photosensitive negative resist having a light blocking property for black matrix is applied in advance to the surface of the glass substrate 16 placed on the exposure stage 11. The exposure stage 11 is moved in the horizontal direction by the driving device so that the photomask 18 and the glass substrate 16 are aligned by an alignment device (not shown). Further, the light shielding plate 13 is moved in the horizontal direction by the driving device so that a part of the opening 19 of the photomask 18 located at the joining portion C of the transfer pattern is shielded.

  In this state, the UV light from the UV lamp 15 is reflected by the curved mirror 14, and the first exposure of the glass substrate 16 is performed through the photomask 18, thereby forming the transfer pattern 20 on the negative resist of the glass substrate 16. To do. At this time, as shown in FIG. 2, the UV light from the UV lamp 15 wraps around the shadow of the light shielding plate 13 due to the diffraction phenomenon, so that the blur A is formed in the joining portion C of the transfer pattern. Here, FIG. 3 shows the result of measuring the length of the blur A when the distance S between the light shielding plate 13 and the glass substrate 16 is changed. It can be seen that the length of the blur A increases as the interval S increases.

After performing the first exposure in this way, the exposure stage 11 is moved in the direction of the arrow in FIG. 1 by the driving device to perform the second exposure. The first exposure exposes the glass substrate 16. The glass substrate 16 is moved relative to the photomask 18 together with the exposure stage 11 so that the transferred pattern and the pattern transferred to the glass substrate 16 by the second exposure partially overlap each other by an overlap amount D. Let Then, the second exposure is performed in a state where a part of the opening 19 of the photomask 18 located at the joining portion C is shielded by the light shielding plate 13.
In the second exposure, as in the first exposure, the UV light from the UV lamp 15 wraps around the shadow of the light shielding plate 13, and a blur A is formed in the joining portion C of the transfer pattern. The

  By the way, due to the relative movement accuracy of the glass substrate 16 with respect to the photomask 18 and the aberration of the optical system of the exposure apparatus, the pattern transferred by the first exposure and the pattern transferred by the second exposure are different. In the meantime, there is a possibility that a positional shift as shown in FIG. That is, the transfer pattern of the black matrix has the first line 21 having the line width W1 by the first exposure and the same line width W1 as the first line 21 and is shifted from the first line 21. The second line 22 by the second exposure is connected to the first line 21 and the second line 22 over the exposure overlap amount D, and the line width W2 is wider than the first and second lines 21 and 22. The third line 23 is provided.

  However, as described above, since the blur A is formed in the joining portion C of the transfer pattern, actually, as shown in FIG. 4B, the second portion located at the boundary portion with the third line 23 is used. A blurring portion 24 that gently changes the line width is formed in the first line 21 and the second line 22. As shown in FIG. 4C, the blur portion 24 becomes longer as the distance S between the light shielding plate 13 and the glass substrate 16 at the time of exposure increases.

When the negative resist on the glass substrate 16 is developed after the first and second exposures are completed, only the portion irradiated with the UV light remains, and the other portions are removed to form a patterned black matrix. It is formed.
Then, a color filter is manufactured by sequentially forming colored layers of R, G, and B in the opening area of the black matrix.

  Here, color filters were produced by changing the exposure overlap amount D, and the appearance of unevenness in the joined portion C was observed using a viewer. When the overlap amount D was 4 mm and 8 mm, unevenness was found in the screen. It was easy to see and when it became 10 mm or more, it turned out that a nonuniformity is hardly visible. The larger the overlap amount D, the better the result. However, since the overlap amount D is limited by the design of the photomask 18 and the design of the exposure apparatus, it is preferable to set the overlap amount D of about 10 to 50 mm. is there.

  Further, various color filters are manufactured by changing the length of the blurring portion 24 by changing the distance S between the light shielding plate 13 and the glass substrate 16 at the time of exposure, and using the viewer, Observing the appearance of unevenness. As a result, it has been found that when the blurring portion 24 has a length of 1 mm or more along the longitudinal direction of the first line 21 and the second line 22, a good screen without unevenness can be obtained.

When the change in the line width of the transfer pattern of the black matrix with respect to the exposure amount was measured, as shown in FIG. 5, the increase amount of the line width increases as the exposure amount increases up to the predetermined exposure amount. It was found that when the exposure amount was exceeded, the line width hardly increased even when the exposure amount was increased, and it became a saturated region. At the joint portion C of the transfer pattern, the first exposure and the second exposure are overlapped and receive an exposure amount twice that of the other portions. Therefore, the line width of the transfer pattern increases as the exposure amount increases. In order to prevent the change, it is preferable to perform each exposure with an exposure amount in a saturated region, for example, an exposure amount of 100 mJ / cm ² or more.

  In the above-described embodiment, the pattern transfer of the entire screen is performed by two exposures using the photomask 18 having an area that is slightly larger than half of the effective area of the glass substrate 16. It is also possible to perform pattern transfer through three or more exposures using a photomask.

It is sectional drawing which shows the structure of the exposure apparatus for enforcing the manufacturing method of the color filter which concerns on embodiment of this invention. It is a figure which shows a mode that a blurring is formed in the joining part of a transfer pattern. It is a graph which shows the relationship of the length of the blurring with respect to the space | interval between a light-shielding plate and a glass substrate. It is a figure which shows the joined part of the transfer pattern obtained by twice exposure. It is a graph which shows the relationship of the increase amount of the line width of the transfer pattern of a black matrix with respect to exposure amount. It is the elements on larger scale which show the structure of a color filter. It is a figure which shows the conventional exposure method at the time of manufacturing a color filter.

Explanation of symbols

  11 exposure stage, 12 mask suction stage, 13 light shielding plate, 14 curved mirror, 15 UV lamp, 16 glass substrate, 17 aperture, 18 photomask, 19 aperture, 20 transfer pattern, 21 first line, 22 second Line, 23 3rd line, 24 Blur part, A Blur, C stitched part, D overlap amount, S Spacing between light shielding plate and glass substrate, W1, W2 Line width.

Claims (4)

In a color filter in which a black matrix is formed in a predetermined pattern on a substrate and a plurality of colored layers are formed in an opening area of the black matrix,
Black matrix
A first line having a predetermined line width;
A second line having the same line width as the first line and being offset from the first line;
A third line connecting the first line and the second line and having a wider line width than the first line;
A blurring portion that is disposed at a boundary portion between the first line and the second line with the third line and that gradually changes the line width from the first line and the second line to the third line. A color filter characterized by that.   2. The color filter according to claim 1, wherein each blur part has a length of 1 mm or more along a longitudinal direction of the first line and the second line. A photomask having a smaller area than the substrate is moved relative to the substrate, and exposure is performed multiple times to connect the transfer patterns to form a black matrix with a predetermined pattern on the substrate and to open the black matrix. In the method for producing a color filter for forming a plurality of colored layers,
Perform exposure in a state where a part of the opening of the photomask located at the joining part of the transfer pattern is shielded by a light shielding plate,
The photomask and the substrate are relatively moved so that the transfer patterns partially overlap each other, and exposure is performed in a state where a part of the opening portion of the photomask located at the joining portion is shielded by a light shielding plate,
A method for producing a color filter, characterized in that blurring is formed at a joining portion of transfer patterns by maintaining a predetermined distance between a light shielding plate and a substrate during exposure.   4. The method for producing a color filter according to claim 3, wherein the exposure is performed with an exposure amount in a saturated region such that the line width of the black matrix transferred onto the substrate hardly changes even if the exposure amount changes.

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