JP2010181687A - Photomask, method for manufacturing color filter, color filter, and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photomask with which a color filter can be manufactured, the color filter including a photospacer having a stable height and an alignment control projection having no recess on the top face formed therein even when a negative photoresist is used, and to provide a method for manufacturing the color filter and the color filter. <P>SOLUTION: The photomask includes a light-transmitting part 53 as a pattern corresponding to the formation of a photospacer Ps and a halftone part 54 as a pattern corresponding to the formation of an alignment control projection Mv. The halftone part includes a light-transmitting part 56 in the center of a semi-transmitting film 55. Upon forming the photospacer into a width of 12 μm and a height of 2.5 to 3.9 μm as well as forming the alignment control projection into a width of 10 μm and a height of 1.0 to 1.5 μm, the semi-transmitting film is made of ITO having a transmittance of 15%, the outer shape of the semi-transmitting film is in a size of 13 to 17 μm, and the light-transmitting part is in a size of 2.0 to 3.0 μm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to the manufacture of a color filter for a liquid crystal display device. In particular, a negative photoresist can be used when simultaneously forming an alignment control protrusion and a photospacer having a width of about 10 μm on a transparent conductive film. The present invention relates to a photospacer having a stable height, a photomask capable of forming an alignment control protrusion having no recess on the upper surface, a color filter manufacturing method, a color filter, and a liquid crystal display device.

  As a method of manufacturing a color filter used in a liquid crystal display device, first, a black matrix is formed on a glass substrate, and then a colored pixel is aligned with the black matrix pattern on the glass substrate on which the black matrix is formed. And a method of forming a transparent conductive film is widely used.

  The black matrix has a light-shielding property, positions the colored pixels of the color filter at the openings of the black matrix, makes the size uniform, and the black matrix is an undesirable light when used in a display device. And has a function of making the image of the display device a uniform image with no unevenness and with improved contrast. For example, the black matrix is formed by a photolithography method using a black photoresist.

The colored pixels have, for example, red, green, and blue color reproduction filter functions, and a negative photoresist in which pigments and other pigments are dispersed on a glass substrate on which the black matrix is formed. A method of forming a colored pixel by providing a film and exposing and developing the coating film is employed.
The transparent conductive film is formed on a glass substrate on which a black matrix and colored pixels are formed by, for example, forming a transparent conductive film by sputtering using ITO (Indium Tin Oxide).

  The color filter manufactured by the above method has a basic function as a color filter used in a liquid crystal display device. With the practical use of various liquid crystal display devices, the color filters used in the liquid crystal display devices have, for example, 1) a protective layer (overcoat layer) and 2) a photomask having a spacer function in addition to the above basic functions. Spacer (protrusion part), 3) alignment control protrusion for controlling the alignment of liquid crystal, 4) optical path difference adjusting layer for aligning the phase of light passing through the transmissive display area and the reflective display area, and 5) reflective display area Various functions such as a light scattering layer are added based on the use and specifications of the color filter.

  FIG. 1 shows that a black matrix (41), a colored pixel (42), and a transparent conductive film (43) are sequentially formed on a glass substrate (40). An alignment control protrusion and a photo are formed on the transparent conductive film (43). It is a top view of an example of the color filter in which the spacer was formed. FIG. 1 is an enlarged schematic view of one pixel of a color filter. FIG. 2 is a cross-sectional view further enlarging a cross section taken along line AA in FIG.

As shown in FIGS. 1 and 2, the color filter shown in this example is provided with a photo spacer (Ps) above the intersection of the black matrix (41) provided in the X-axis and Y-axis directions in FIG. It has been. Further, as the orientation control protrusion (Mv), a circular orientation control protrusion is provided in plan view. In the color filter used for the liquid crystal display device for TV, the alignment control protrusion (Mv) is provided with the stripe-shaped alignment control protrusion bent in the pixel in a plan view, but the pixel has a high-definition mobile liquid crystal display device In the color filter used in the above, circular orientation control protrusions are used in plan view in order to keep the aperture ratio high. 1 and 2 is an example in which four alignment control protrusions (Mv) are provided in a pixel.

  The height (h12) of the photo spacer (Ps) that sets the interval between the substrates constituting the liquid crystal display device is about 2 to 4 μm, and the height (h11) of the alignment control protrusion (Mv) that controls the alignment of the liquid crystal. ) Is about 0.8 to 1.5 μm. The height (h12) of the photo spacer (Ps) and the height (h11) of the orientation control protrusion (Mv) are in a relationship of h12> h11.

  3 and 4 are cross-sectional views showing an example of a method for forming the alignment control protrusions (Mv) and the photo spacers (Ps) constituting the color filter shown in FIG. 1 and FIG. In this forming method, the alignment control protrusion and the photo spacer are formed on the transparent conductive film (43) by two steps of a photolithography process for forming the alignment control protrusion (Mv) and a photolithography process for forming the photo spacer (Ps). It is a method of forming.

As shown in FIG. 3A, a photoresist layer (60) is formed on a glass substrate (40) on which a black matrix (41), a colored pixel (42), and a transparent conductive film (43) are sequentially formed. Has been. As the photoresist for forming the alignment control protrusion (Mv), a positive photoresist is widely used in view of the required cross-sectional shape and electrical characteristics.
However, for example, when forming a circular alignment control protrusion having a width of about 10 μm, such as a width of 9 to 13 μm, when exposure is performed by proximity exposure, the alignment control protrusion formed due to variation in the gap amount of the proximity exposure in the exposure apparatus Therefore, when forming a circular alignment control protrusion having a width of about 10 μm, a negative photoresist that is less affected by the variation in gap amount is used. FIG. 3A shows an example in which a negative photoresist is used.

  In FIG. 3A, a proximity exposure gap (G) is provided above the photoresist layer (60), and the photomask (PM) has its film surface (31) opposed to the photoresist layer (60). Are arranged. As shown in FIG. 3A, the photomask (PM) is provided with a light transmitting portion (33) corresponding to the formation of the alignment control protrusion (Mv), and portions other than the light transmitting portion (33) are It is a light shielding part (32).

As shown in FIG. 3A, the photoresist layer (60) for forming the alignment control protrusion (Mv) is exposed (E) through a photomask (PM) and is higher than the photospacer (Ps). Low alignment control protrusions (Mv). In FIG. 3A, a state in which the development processing has already been completed and the orientation control protrusion (Mv) is formed is indicated by a dotted line.
The thickness (H1) of the photoresist layer (60) is set so that the height and width of the formed alignment control protrusion (Mv) are satisfactorily formed. Therefore, as shown in FIG. 3B, the height (h1) and the width (w1) of the orientation control protrusion (Mv) obtained after the development processing are the desired height and width.

4A and 4B illustrate a method of subsequently forming a photospacer (Ps) on the transparent conductive film (43) on which the alignment control protrusion (Mv) shown in FIG. 3B is formed. FIG. As shown in FIG. 4A, a photoresist layer is formed on a glass substrate (40) on which a black matrix (41), a colored pixel (42), a transparent conductive film (43), and an alignment control protrusion (Mv) are formed. (60-2) is formed.
FIG. 4A shows an example in which a negative photoresist is used as a photoresist for forming a photospacer. For the formation of the photo spacer, a negative photoresist is widely used.

In FIG. 4 (a), a proximity exposure gap (G2) is provided above the photoresist layer (60-2), and the photomask (PM2) has a film surface (31) on the photoresist layer (60-2). ).
As shown in FIG. 4A, the photomask (PM2) is provided with a light transmitting portion (33) corresponding to the formation of the photo spacer (Ps), and the portions other than the light transmitting portion (33) are shielded. Part (32).

A photo spacer (Ps) provided in a color filter used in a liquid crystal display device for mobile with high-definition pixels has a width of about 10 μm, for example, a width of 9 to 13 μm. When forming a photo spacer (Ps) having a width of about 10 μm, the gap amount of the proximity exposure is performed, for example, at about 100 μm.
However, since the gap amount variation in the exposure apparatus is about 40 μm in the range, if the gap amount is set to 100 μm or less, depending on the film surface (31) of the photomask (PM2), The surface of the photoresist layer (60-2) may come into contact.

On the other hand, if the gap amount is sufficiently large, for example, 150 μm or more, the light intensity on the exposure surface of the light that has passed through the light transmitting part (33) on the photomask (PM2) is weakened, and the photoresist layer A sufficient amount of light necessary for curing cannot be obtained, and it becomes difficult to form a stable photospacer (Ps).
Accordingly, the gap (G2) for the proximity exposure when forming the photo spacer (Ps) having a width of about 10 μm is 100 μm to 150 μm, and is considered to be 100 μm to 130 μm in consideration of the gap amount variation at 150 μm.

FIG. 5 and FIG. 6 are explanatory diagrams of the result of simulating the relationship between the gap amount and the light intensity on the exposure surface when the width of the light transmitting portion (33) is 10 μm. In FIG. 5, the thick line curve indicates the case where the gap amount is 100 μm, and in FIG. 6, the thick line curve indicates the case where the gap amount is 150 μm.
As shown in FIGS. 5 and 6, when the gap amount is 100 μm, the light intensity at the center of the light transmitting portion is about 1.20, whereas when the gap amount is 150 μm, the light intensity at the center of the light transmitting portion is It has attenuated to about 0.6. This proves that when the gap amount is 150 μm or more, a sufficient amount of light necessary for curing the photoresist layer cannot be obtained, and it is difficult to form a stable photospacer (Ps). .

Accordingly, as shown in FIG. 4A, exposure (E) is performed with the gap (G2) kept at 100 μm to 130 μm through the photomask (PM2) through the photoresist layer (60-2) for forming the photospacer. As a result, a photospacer (Ps) having a height higher than that of the alignment control protrusion (Mv) is formed. In FIG. 4 (a), a state in which the development process has already been completed and the photospacer (Ps) is formed is indicated by a dotted line.
The thickness (H2) of the photoresist layer (60-2) is set so that the height and width of the formed photospacer (Ps) are satisfactorily formed. Therefore, as shown in FIG. 4B, the height (h2) and width (w2) of the photospacer (Ps) obtained after the development processing are the desired height and width.

  As described above, the alignment control protrusion and the photospacer are formed on the transparent conductive film (43) by the two steps of the photolithography process for forming the alignment control protrusion (Mv) and the photolithography process for forming the photospacer (Ps). The forming method is a method in which the height and width of the alignment control protrusion (Mv) and the photospacer (Ps) can be satisfactorily formed to a desired height and width.

  However, there is a strong demand for an inexpensive color filter, even if it is a color filter having specifications with alignment control protrusions (Mv) and photo spacers (Ps) added, so that the number of processes can be reduced. Various techniques have been proposed (see Patent Literature).

FIG. 7A is a cross-sectional view showing an example of a method for simultaneously forming the alignment control protrusion (Mv) and the photospacer (Ps) in one process using the same photoresist.
FIG. 7A shows a case where a negative photoresist is used as the same photoresist. As shown in FIG. 7 (a), a photo using a negative photoresist on a glass substrate (40) on which a black matrix (41), a colored pixel (42), and a transparent conductive film (43) are sequentially formed. A resist layer (60-3) is provided.

  In FIG. 7A, a proximity exposure gap (G3) is provided above the photoresist layer (60-3), and the photomask (PM3) faces the photoresist layer (60-3). Are arranged. The photomask (PM3) is provided with a translucent portion (33) corresponding to the formation of the photo spacer (Ps) and a semi-transparent portion (34) corresponding to the formation of the alignment control protrusion (Mv). .

As shown in FIG. 7A, the photoresist layer (60-3) is exposed (E) through a photomask (PM3), and the alignment control protrusion (Mv) is lower than the photospacer (Ps). ) At the same time as the formation of the photospacer (Ps).
In FIG. 7A, the alignment control protrusion (Mv) and the photospacer (Ps) in a state where the development processing has already been completed and formed are indicated by dotted lines.
In order to form the alignment control protrusion (Mv) having a height lower than that of the photospacer (Ps) simultaneously with the photospacer (Ps), a semi-transparent portion (34) corresponding to the formation of the alignment control protrusion (Mv) is provided. It has been. A photomask (PM3) shown in FIG. 7A is an example in which a semi-translucent portion (34) is used.

The semi-transparent portion (34) shown in FIG. 7 (a) is a halftone portion made of a semi-transparent film, and is a thin film that attenuates ultraviolet rays, for example, a thin film made of a metal oxide film, and has a uniform thickness. It has been.
For example, when the exposure to the photoresist layer (60-3) is appropriately performed through the translucent portion (33) so that the photo spacer (Ps) having the height (h4) is formed satisfactorily. Further, the transmissivity of the semi-transparent film is set by the film thickness so that the exposure through the semi-transparent portion (34) to the height (h3) orientation control protrusion (Mv) is also appropriately performed.

  FIG. 7B is a cross-sectional view of the orientation control protrusion (Mv) at the stage after the development processing. A negative photoresist is used as the photoresist, and a light transmitting part (33) corresponding to the formation of the photo spacer (Ps) and a semi-transparent part (34) corresponding to the formation of the alignment control protrusion (Mv) are used as the photomask. The alignment control protrusion (Mv) obtained by performing exposure with the proximity exposure gap (G3) set to, for example, 100 μm through a photomask provided with a recess has a problem in that a recess is formed on the upper surface thereof. .

  FIG. 8 is an explanatory diagram of the result of simulating the relationship between the gap amount and the light intensity on the exposure surface when the width of the semi-translucent portion (34) on the photomask is 20 μm. In FIG. 8, when the gap amount is 100 μm, the light intensity at the center of the semi-translucent portion is about 0.15, but in the vicinity of the coordinate in the width direction of ± 4 μm, as indicated by reference numeral (A). The light intensity is as high as about 0.20. The attenuation of the light intensity at the center of the semi-translucent portion is a proof that a concave portion is formed on the upper surface of the formed alignment control protrusion (Mv).

In addition, as shown by a symbol (B) in FIG. 8, when the gap amount is 150 μm, the light intensity at the center of the semi-translucent portion is increased to about 0.22, so that the alignment control protrusion (Mv) The concave portion on the upper surface of is eliminated. When scrutinized, the gap on the upper surface of the alignment control protrusion is eliminated by keeping the gap amount at 140 μm or more. However, considering the variation in the gap amount of the exposure apparatus, it is necessary to keep the gap amount at 180 μm or more. come.

This is because a photospacer (Ps) having a width of about 10 μm provided in a color filter used in a liquid crystal display device for mobile use with a high-definition pixel and an alignment control protrusion (about 10 μm in width lower than the photospacer (Ps)). When Mv) is simultaneously formed using a negative photoresist, the gap amount for proximity exposure is preferably in the range of 100 μm to 130 μm for the formation of a good photospacer (Ps), while good alignment control For the formation of the protrusion (Mv), 140 μm or more is suitable, and there is no suitable gap amount range common to both, and it can be said that they are in conflict.
Japanese Patent No. 4132528 Japanese Patent No. 3255107 Japanese Patent No. 3651874 JP 2005-84366 A

  The present invention has been made in order to solve the above-mentioned problems. The transparent substrate is provided with a black matrix (41), a colored pixel (42), and a transparent conductive film (43) on a glass substrate (40). In the manufacture of a color filter in which an alignment control protrusion having a width of about 10 μm and a photospacer having a width of about 10 μm are provided on the conductive film (43), a negative photoresist is used as a photoresist for forming the alignment control protrusion and the photospacer. It is an object of the present invention to provide a photomask that makes it possible to manufacture a color spacer in which an alignment control protrusion having no recess is formed on the upper surface and a photo spacer having a stable height even when using. It is another object of the present invention to provide a color filter manufacturing method, a color filter, and a liquid crystal display device using the photomask.

  In addition, this makes it possible to obtain a color filter in which the height of the photo spacer is stable and no concave portion is formed on the upper surface of the alignment control protrusion even when the negative photoresist is used, and the photo mask is inexpensive. In addition, it is possible to provide a color filter at a low cost by shortening the construction period.

The present invention provides a photomask that uses a negative photoresist and simultaneously forms a photo spacer and an alignment control protrusion by proximity exposure.
1) A pattern corresponding to the formation of the photo spacer on the photo mask is a translucent portion,
2) A pattern corresponding to the formation of the alignment control protrusion on the photomask is a halftone portion, and the halftone portion is a translucent portion (in the central portion of a semi-transparent film having a circular or polygonal outer shape). The photomask is provided with an opening).

  Further, the present invention is the photomask according to the invention, wherein the material of the semi-translucent film has a transmittance of 10 to 15% at a wavelength of 365 nm.

In the photomask according to the present invention, the width of the photo spacer is 12 μm, the height is 2.5 to 3.9 μm, the width of the alignment control protrusion is 10 μm, and the height is 1.0 to When forming to 1.5 μm,
1) The material of the translucent film is chromium oxide having a transmittance of 10% at a wavelength of 365 nm,
2) The photomask is characterized in that the circular or polygonal translucent film has an outer shape of 12 to 17 μm and a light transmitting portion (opening) of 2.0 to 6.0 μm.

Further, the present invention provides a color filter manufacturing method in which at least a black matrix, a colored pixel, and a transparent conductive film are formed on a glass substrate, and a photo spacer and an alignment control protrusion are formed on the transparent conductive film.
1) a step of sequentially forming at least a black matrix and colored pixels on the glass substrate;
2) a step of forming a transparent conductive film on the entire surface of the glass substrate on which the black matrix and colored pixels are formed;
3) A step of providing a negative photoresist coating film on the glass substrate on which the transparent conductive film is formed, and forming a photospacer and an alignment control protrusion by a proximity exposure through a photomask and a development process. Equipped,
A method for producing a color filter, wherein the photomask according to claim 1, claim 2, or claim 3 is used as the photomask, and a photospacer and an alignment control protrusion are formed simultaneously.

  Moreover, the present invention is a color filter manufactured using the method for manufacturing a color filter according to claim 4.

  The present invention also provides a liquid crystal display device using the color filter according to claim 5.

  The present invention uses a negative photoresist, and in the photomask in which the photospacer and the alignment control protrusion are simultaneously formed by proximity exposure, the pattern corresponding to the formation of the photospacer on the photomask is a translucent portion, A pattern corresponding to the formation of the alignment control protrusion on the photomask is a halftone portion, and the halftone portion is formed at a central portion of a semi-transparent film having a circular or polygonal outer shape. In the manufacture of a color filter in which an alignment control protrusion having a width of about 10 μm and a photospacer having a width of about 10 μm are provided at the same time, a negative photoresist is used as a photoresist for forming the alignment control protrusion and the photospacer. Even when using, a photo spacer with a stable height and an alignment control protrusion that does not form a recess on the top surface are formed. This is a photomask that makes it possible to produce a color filter.

  In the photomask according to the present invention, the material of the semi-transparent film is chromium oxide having a transmittance of 10% at a wavelength of 365 nm, and the outer shape of the circular or polygonal semi-transparent film is 12 to 12. Since 17 μm and the light transmitting part (opening) are 2.0 to 6.0 μm, the width of the photo spacer is 12 μm, the height is 2.5 to 3.9 μm, and the height is stabilized. The photomask can be formed so that the width of the alignment control protrusion is 10 μm, the height is 1.0 to 1.5 μm, and no recess is formed on the upper surface thereof.

In the present invention, since the color filter is manufactured using the photomask, a photo spacer having a stable height and an alignment control protrusion that does not have a concave portion are formed even when a negative photoresist is used. A color filter can be manufactured.
As a result, the photomask is inexpensive, and it is possible to provide a color filter at a low cost and with a shortened construction period.

  Further, since the present invention is a liquid crystal display device using the color filter, it is possible to provide a liquid crystal display device at a low cost and with a shortened construction period.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 9 is a cross-sectional view showing an example of a photomask according to the present invention. This photomask (PM4) is a photomask in which a photospacer and an alignment control protrusion constituting a color filter are simultaneously formed using a negative photoresist. The photomask (PM4) shown in FIG. 9 is an enlarged cross-sectional view of a portion on the photomask corresponding to the formation of the same portion as the portion indicated by the AA line of the color filter shown in FIG.

  As shown in FIG. 9, the photomask (PM4) has a pattern (translucent part (53)) corresponding to the formation of the photospacer (Ps) and an alignment control protrusion (Mv) having a height lower than that of the photospacer. A pattern (halftone part (54)) corresponding to the formation is provided. The light shielding part (52) is a uniform light shielding film, for example, a low reflection film using Cr and CrO. The pattern corresponding to the formation of the photospacer (Ps) (the translucent portion (53)) is an opening.

FIG. 10A is an enlarged plan view showing a pattern (halftone portion) (54) corresponding to the formation of the alignment control protrusion (Mv) shown in FIG. FIG. 10B is a cross-sectional view taken along line BB in FIG.
As shown in FIGS. 10A and 10B, the pattern (halftone portion) (54) corresponding to the formation of the alignment control protrusion (Mv) is the center of the semi-translucent film (55) whose outer shape is a regular octagon. It is the structure by which the transparent part (opening part) (56) was provided in the part.

The halftone part (54) is composed of a fine semi-transparent film (55) part that shields light halfway and a fine translucent part (opening part) (56) part that transmits light.
The semi-transparent portion (34) shown in FIG. 7 (a) is a halftone portion made of a semi-transparent film. The semi-transparent film is made of, for example, a thin film made of a metal oxide having a uniform thickness. It is provided uniformly.
On the other hand, the halftone part (54) in the present invention is one in which a translucent part (opening part) (56) is provided in the central part of the semitranslucent film (55). Therefore, the light intensity at the center of the semi-translucent portion when the gap amount is 100 μm (symbol A) shown in FIG. 8 is enhanced. Thereby, even if the gap amount is not 150 μm (reference B), that is, even when the gap amount is 100 μm, no concave portion is formed on the upper surface of the formed alignment control protrusion.

  FIGS. 11A and 11B show a pattern corresponding to the formation of the photospacer (translucent portion (53)) and a pattern corresponding to the formation of the alignment control protrusion (Mv) having a height lower than the photospacer (half). Using the photomask (PM4) shown in FIG. 9 provided with a tone portion (54)), the photospacer (Ps) and the alignment control protrusion (Mv) are simultaneously formed in one step using the same photoresist. It is explanatory drawing of the manufacturing method of the color filter by this invention.

  FIG. 11A shows a case where a negative photoresist is used as the same photoresist. As shown in FIG. 11A, a photo using a negative photoresist on a glass substrate (40) on which a black matrix (41), a colored pixel (42), and a transparent conductive film (43) are sequentially formed. A resist layer (60-4) is provided.

In FIG. 11A, a proximity exposure gap (G4) is located above the photoresist layer (60-4).
) And a photomask (PM4) is disposed with its film surface facing the photoresist layer (60-4). The photoresist layer (60-4) is exposed (E) through a photomask (PM4), and the alignment control protrusion (Mv) having a height lower than that of the photospacer (Ps) is formed to form the photospacer (Ps). Form at the same time. In FIG. 11A, the alignment control protrusion (Mv) and the photospacer (Ps) in a state where the development processing has already been completed and formed are indicated by dotted lines.

  The exposure to the photoresist layer (60-4) is appropriate via the light transmitting portion (53) so that the photo spacer (Ps) having the height (h6) shown in FIG. In this case, the transmittance of the halftone part is set so that the exposure through the halftone part (54) to the orientation control protrusion (Mv) having the height (h5) is appropriately performed. .

  FIG. 11B is a cross-sectional view of the orientation control protrusion (Mv) at the stage after the development processing. A negative photoresist is used as the photoresist, and a light transmitting portion (53) corresponding to the formation of the photo spacer (Ps) and a halftone portion (54) corresponding to the formation of the alignment control protrusion (Mv) are used as the photomask. The alignment control protrusion (Mv) obtained by performing exposure with the proximity exposure gap (G4) through the provided photomask has a so-called bowl-like shape without forming a recess on its upper surface.

As described above, this is because the gray tone portion according to the present invention corresponds to the formation of the alignment control protrusion on the photomask when the alignment control protrusion (Mv) having a height lower than that of the photospacer (Ps) is simultaneously formed. This is because light from the translucent part (opening part) (56) in the central part of the semi-transparent film (55) enhances the light intensity in the central part of the gray tone part.
In addition, the material of the semi-transparent film in the present invention is characterized in that the transmittance is 10 to 15% at a wavelength of 365 nm.

Examples will be described in detail below.
<Example 1>

A) Using a non-alkali glass having a thickness of 0.5 mm as a substrate for forming a black matrix, applying a black photoresist on the substrate with a spin coater, pre-baking and then exposing, developing, and post-baking through a predetermined photomask, A black matrix having a thickness of 1.4 μm was formed.
B) Formation of colored pixels On the substrate on which the black matrix was formed, a red photoresist was applied by a spin coater, and after pre-baking, exposure, development, and post-baking were performed through a predetermined photomask to form red colored pixels. . Similarly, a green colored pixel and a blue colored pixel were formed, and each film thickness was 1.5 μm.
C) Formation of transparent conductive film On the substrate on which the colored pixels were formed, an indium tin oxide film was formed to a thickness of 0.14 μm by sputtering and a transparent conductive film was formed.

D) Formation of photo spacer and alignment control protrusion a) As a photoresist, Adeka Co., Ltd .: negative photoresist (TA2000 (product number)) was used. On the transparent conductive film, a negative photoresist was applied with a spin coater, pre-baked, and then exposed, developed, and post-baked through the following photomask to form photo spacers and alignment control protrusions. The exposure was performed by proximity exposure with a gap amount of 100 μm to give an i-line exposure amount of 150 mJ / cm ² .
b) Photomask The photomask uses quartz glass with a size of 410 × 515 mm and a thickness of 5 mm, and the material of the semi-transparent film corresponding to the formation of the alignment control protrusion is ITO having a transmittance of 15% at a wavelength of 365 nm. It was. Since the height of the practical photo spacer is about 2 to 4 μm and the height of the alignment control protrusion is about 0.8 to 1.5 μm, the numerical values of Case 1 to Case 4 shown in Table 1 below are set as target values. Determined. Table 2 below shows the width (b) of the translucent film (55) on the photomask shown in FIG. 10 and the translucent portion, which were set to form the photo spacers and the alignment control protrusions of the cases 1 to 4. The numerical value of the width (a) of (opening) (56) is shown.

c) Photospacer and orientation control protrusion obtained As a result of forming the photospacer and the orientation control protrusion as shown in FIG. 11, good results were obtained as shown in Table 3 below. That is, as is clear when the target values in Table 1 are compared with the numerical values in Table 3, the targets are achieved in any of Case 1 to Case 4. In cases 1 and 2, when the height of the photo spacer is 3.92 μm, the height of the alignment control protrusion is 1.11 and 1.55 μm, and the shape is well formed in a bowl shape. . In cases 3 and 4, when the height of the photo spacer is 2.56 μm, the heights of the alignment control protrusions are 0.99 and 1.65 μm, and the shape is well formed in a bowl shape. ing.
By using the photomask according to the present invention, it is possible to set the gap amount for proximity exposure to 100 μm, which is a suitable gap amount common to both the photo spacer (Ps) and the alignment control protrusion (Mv). The height of the spacer is stable, and no recess is formed on the upper surface of the orientation control protrusion.

  <Example 2>

a) As the materials of the semi-translucent film corresponding to the formation of the photomask alignment control protrusion, the following two kinds of materials were used, Case 5 and Case 6, and target values shown in Table 4 below were determined.
A) CrO film (A film) having a transmittance of 10% and a phase shift of 29 ° at a wavelength of 365 nm
B) CrO film (B film) with a transmittance of 10% and a phase shift of 147 ° at a wavelength of 365 nm
The same procedure as in Example 1 was performed except that the semi-transparent film was different.
Table 5 below shows the width (b) and translucent part (opening part) of the semi-translucent film (55) on the photomask, which were set to form the photo spacers and the alignment control protrusions of the above case 5 to case 6. The numerical value of the width (a) of (56) is shown.

b) The obtained photospacer and alignment control protrusion As shown in Table 6 below, good results were obtained. That is, as is clear when the target values in Table 4 are compared with the numerical values in Table 6, the targets are achieved in both cases 5 and 6.
In cases 5 and 6, when the height of the photospacer is 3.85 and 3.88 μm, the height of the alignment control protrusion is 1.16 and 1.18 μm, and the shape is good like a bowl. Is formed.
By using the photomask according to the present invention, it is possible to set the gap amount for proximity exposure to 100 μm, which is a suitable gap amount common to both the photo spacer (Ps) and the alignment control protrusion (Mv). The height of the spacer is stable, and no recess is formed on the upper surface of the orientation control protrusion.

＜比較例１＞

<Comparative Example 1>

a) Photomask A photomask (PM3) shown in FIG. 7A was used as a photomask. FIG. 12A is an enlarged plan view of the translucent portion (33) of the photomask (PM3), and a sectional view taken along the line CC of the plan view. FIG. 12B is an enlarged plan view of the semi-transparent portion (34) of the photomask (PM3) and a cross-sectional view taken along the line DD of the plan view. The material of the semi-translucent film corresponding to the formation of the alignment control protrusion was ITO having a transmittance of 15% at a wavelength of 365 nm. The width (c) of the translucent part (33) was 10 μm, and the width (d) of the semi-translucent part (34) was 20 μm.
The gap amount was set to 100 μm and 150 μm, the gap amount of 100 μm was set to Case 7, and the gap amount of 150 μm was set to Case 8.
The same procedure as in Example 1 was performed except for the above-described photomask and gap amount setting. The numerical values shown in Table 7 below were determined as target values for cases 7 and 8.

b) Resulting Photospacer and Orientation Control Protrusion As a result of forming the photospacer and orientation control protrusion as shown in FIG. 7, the gap amount is 100 μm in Case 7 as shown in Table 8 below. The height of the photospacer was stable, but a recess was formed on the upper surface of the orientation control protrusion. In case 8, since the gap amount was 150 μm, the top surface of the alignment control protrusion was bowl-shaped, but the height of the photospacer was highly variable and unstable.

It is a top view of an example of the color filter in which the alignment control protrusion and the photo spacer were formed on the transparent conductive film on the glass substrate. It is sectional drawing which expanded further and showed the cross section in the AA in FIG. It is sectional drawing which shows an example of the method of forming the orientation control protrusion and photo spacer which comprise the color filter shown in FIG.1 and FIG.2. It is sectional drawing which shows an example of the method of forming the orientation control protrusion and photo spacer which comprise the color filter shown in FIG.1 and FIG.2. It is explanatory drawing of the result of having simulated the relationship between the gap amount and the light intensity in an exposure surface in case the width | variety of a translucent part is 10 micrometers. It is explanatory drawing of the result of having simulated the relationship between the gap amount and the light intensity in an exposure surface in case the width | variety of a translucent part is 10 micrometers. (A) is sectional drawing which shows an example of the trial of the method of forming simultaneously an orientation control protrusion and a photo spacer in 1 process using the same photoresist. (B) is sectional drawing of the orientation control protrusion in the stage after development processing. It is explanatory drawing of the result of having simulated the relationship between the gap amount and the light intensity in an exposure surface in case the width | variety of the semi-transparent part on a photomask is 20 micrometers. It is sectional drawing which shows an example of the photomask by this invention. FIG. 10A is an enlarged plan view showing a pattern (halftone portion) corresponding to the formation of the alignment control protrusion shown in FIG. 9. (B) is sectional drawing in the BB line of Fig.10 (a). (A), (b) is explanatory drawing of the manufacturing method of the color filter by this invention which forms a photo spacer and alignment control protrusion simultaneously by 1 process using the same photoresist. (A) is the top view and sectional drawing which expanded the translucent part of the photomask. (B) is the top view and sectional drawing which expanded the semi-transparent part of the photomask.

31 ... Film surface 32 ... Shading part 33, 53 ... Translucent part 34 ... Semi-translucent part 40 ... Glass substrate 41 ... Black matrix 42 ... Colored pixel 43 ... -Transparent conductive film 52-light-shielding part 54-gray tone part 55 in the present invention-semi-transparent film 56 having a circular or regular octagonal outer shape-translucent part (opening)
60, 60-2, 60-3, 60-4 ... photoresist layer E ... exposure light G, G2, G3, G4 ... gap H1, H2 of proximity exposure ... thickness of photoresist layer Mv ... alignment control protrusion Ps ... photo spacer PM, PM2, PM3 ... photomask PM4 ... photomask h11 in the present invention ... height h12 of the alignment control protrusion ... Height w1 Width of orientation control protrusion

Claims (6)

In a photomask that uses a negative photoresist and simultaneously forms a photospacer and alignment control protrusion by proximity exposure,
1) A pattern corresponding to the formation of the photo spacer on the photo mask is a translucent portion,
2) A pattern corresponding to the formation of the alignment control protrusion on the photomask is a halftone portion, and the halftone portion is a translucent portion (in the central portion of a semi-transparent film having a circular or polygonal outer shape). An opening portion is provided.   2. The photomask according to claim 1, wherein the material of the semi-transparent film has a transmittance of 10 to 15% at a wavelength of 365 nm. When the width of the photo spacer is 12 μm and the height is 2.5 to 3.9 μm, and the width of the alignment control protrusion is 10 μm and the height is 1.0 to 1.5 μm,
1) The material of the translucent film is chromium oxide having a transmittance of 10% at a wavelength of 365 nm,
2) The outer shape of the circular or polygonal translucent film is 12 to 17 μm, and the translucent portion (opening) is 2.0 to 6.0 μm. Photo mask. In a color filter manufacturing method in which at least a black matrix, a colored pixel, and a transparent conductive film are formed on a glass substrate, and a photo spacer and an alignment control protrusion are formed on the transparent conductive film.
1) a step of sequentially forming at least a black matrix and colored pixels on the glass substrate;
2) a step of forming a transparent conductive film on the entire surface of the glass substrate on which the black matrix and colored pixels are formed;
3) A step of providing a negative photoresist coating film on the glass substrate on which the transparent conductive film is formed, and forming a photospacer and an alignment control protrusion by a proximity exposure through a photomask and a development process. Equipped,
A method for manufacturing a color filter, wherein the photomask according to claim 1, claim 2, or claim 3 is used as the photomask, and a photospacer and an alignment control protrusion are formed simultaneously.   A color filter manufactured using the method for manufacturing a color filter according to claim 4.   A liquid crystal display device using the color filter according to claim 5.

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