TWI620001B - Photomask and color filter manufacturing method - Google Patents

Abstract

The invention provides a photomask capable of suppressing an increase in equipment investment and a decrease in production efficiency, and capable of forming a line pattern having a fine portion with a line width of 2 μm to 10 μm by a photolithography method, and a manufacturing method of a substrate using the same. .

The invention provides a photomask and a method for manufacturing a substrate using the photomask. The photomask is used to form a line pattern having a fine portion with a line width of 2 μm to 10 μm, and a peripheral area surrounding the line pattern, and includes: A light-shielding portion; a semi-light-transmitting portion corresponding to the line pattern; and a light-transmitting portion surrounding the light-shielding portion and the semi-light-transmitting portion corresponding to the peripheral region; the width of the semi-light-transmitting portion is larger than that of the line pattern The above fine parts are larger.

Description

Photomask and color filter manufacturing method

The present invention relates to a photomask capable of forming a fine pattern on a substrate by a photolithography method, particularly a line pattern having a fine portion with a line width of 2 μm to 10 μm, and a method for manufacturing the substrate using the photomask.

The technique of forming a pattern on a substrate by a photolithography method is widely spread, but in recent years, it is strongly desired to form a line pattern having a fine portion with a line width of 10 μm or less.

In view of this situation, if the field of display devices is taken as an example, in recent years, various display devices including liquid crystal display devices, plasma display devices, and organic EL (electro luminescence) display devices have been put into practical use. Prevail. Among them, among the color filters used in liquid crystal display elements for color display of liquid crystal display devices, there are thin three primary color filters on a transparent substrate that have a thickness of about 1 μm corresponding to each pixel electrode. Filters (red, green, and blue filters), in order to prevent the incident light from leaking from the gaps between the filters and reduce the contrast of the liquid crystal display, a light shielding is arranged between the filters Part is the black matrix.

This black matrix will shield all the parts that do not contribute to the display, that is, the source wiring of the liquid crystal display element or the gap between the pixel electrode and the source wiring. Here, in order to make the liquid crystal display bright, it is desirable to reduce the light-shielding portion of the black matrix as much as possible, that is, to refine the line width of the black matrix.

Conventionally, as described in Patent Document 1 shown below, a black matrix of a color filter is manufactured in the following procedure.

First, a negative-type photosensitive material is disposed on a color filter substrate. Then, a photomask is arranged at a specific distance from the photosensitive material, and the photosensitive material is exposed through the photomask. Then, the exposed photosensitive material is developed, and the exposed portion is formed into a black matrix of a color filter.

At this time, in particular, in order to make the liquid crystal display bright, the black matrix of the color filter is required to be refined, and specifically, the width of the black matrix is required to be in a range of 2 μm to 10 μm. Therefore, it is considered that the line width of the exposed area in the photosensitive material on the color filter substrate is reduced by forming a fine pattern in the light-shielding film in the photomask.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2000-199967

However, in the manufacture of color filters, the mainstream method is to use a proximity exposure method in which a mask pattern is transferred to the substrate by setting the interval between the photomask and the photosensitive substrate extremely small and irradiating light. A photosensitive material disposed on one surface of a large-area substrate is exposed. Specifically, exposure is performed by irradiating light with a wavelength of 365 nm (i-ray) to 436 nm (g-ray) from a light source such as a mercury lamp, and exposing it through a mask disposed at a fixed gap from the substrate. Therefore, if a fine pattern is formed on the light-shielding film of the photomask in the manner described above, the effect of diffraction of light at the edges of the pattern becomes large, and the exposure amount to the photosensitive material is reduced. In this way, the amount of light does not reach the threshold value for sensitizing the photosensitive material, the hardening degree of the photosensitive material decreases, and there is a problem that the resolution is reduced.

In order to solve the above-mentioned problem of reduction in resolution, it is considered that instead of using proximity exposure, a lens projection step developed using a technology previously developed as a technology for manufacturing LSI (Large Scale Integration) is used. Projector and mirror projection stepper (MPA: Mirror Projection Aligner) Light. Further, it is considered to increase the numerical aperture (NA) of the exposure machine, shorten the wavelength (λ) of the light to be exposed, and apply a phase shift mask. However, the application of these technologies requires huge investment and technological development, and the production efficiency will be reduced, so it is not easy.

In addition, in order to increase the exposure amount in the photolithography method, it is necessary to increase the output of the light source of the exposure machine or increase the exposure time, which will lead to additional investment in equipment reconstruction or reduction in production efficiency, and is difficult to achieve.

Furthermore, in the case of increasing the exposure amount, the line width of the black matrix after curing will become wider as the exposure amount to the photosensitive material increases, and a problem that the refinement of the black matrix cannot be achieved.

In this way, it is expected that the line width of the black matrix of the color filter will be reduced without adding huge investment and without compromising production efficiency.

As described above, an object of the present invention is to provide a photomask capable of suppressing an increase in equipment investment and a decrease in production efficiency, and capable of forming a line pattern having a fine portion with a line width of 2 μm to 10 μm by a photolithography method, and using the same. Photomask manufacturing method.

One embodiment of the photomask of the present invention for solving the above-mentioned problems is a photomask for forming a line pattern having a fine portion with a line width of 2 μm to 10 μm, and a peripheral region surrounding the line pattern, which is characterized in that: Including: a light-shielding portion; a semi-light-transmitting portion corresponding to the line pattern; and a light-transmitting portion surrounding the light-shielding portion and the semi-light-transmitting portion corresponding to the peripheral region; the width of the semi-light-transmitting portion is larger than that of the line pattern The above fine parts are larger.

According to this aspect, the width of each translucent portion corresponding to the line pattern is made larger than that of each of the line patterns, so that even if light diffraction occurs, it is possible to use a light-sensitive material that is sufficiently sensitive to light. Area with a light amount (that is, contrast), and by using a translucent film, the exposure light amount irradiated to the area for forming a wired pattern can be adjusted to form a desired width having a width in a range of 2 μm to 10 μm. Fine line patterns, on the other hand, can illuminate the light-transmitting portion with a sufficient amount of exposure light to form the surrounding area reliably. The area surrounding the winding pattern.

As described above, according to this embodiment, only by changing the photomask, it is possible to continue to use the previous high-efficiency equipment without changing to an expensive exposure device used in the semiconductor field. That is, an increase in equipment investment and a decrease in production efficiency can be suppressed, and a line pattern having a fine portion with a line width of 2 μm to 10 μm and a peripheral region surrounding the line pattern can be reliably formed.

Another embodiment of the method for manufacturing a photomask of the present invention is characterized in that when the width of the fine portion of the line pattern is set to Wb and the width of the translucent portion is set to Ws, the Wb and Ws satisfies the relationship of 1.2 ≦ Ws / Wb ≦ 3.

According to this embodiment, as long as the width dimension of the semi-transmissive portion is within the range of 1.2 times to 3 times the width dimension of the fine portion of the line pattern, the above-mentioned effect can be reliably exhibited.

Another embodiment of the method for manufacturing a photomask of the present invention is characterized in that the photomask is used for proximity exposure.

According to this embodiment, exposure is performed in a region where a sufficient exposure light amount (preferable contrast) can be obtained. Therefore, even in a case where the proximity exposure gap fluctuates, unevenness in the line width of the line pattern can be suppressed.

Another embodiment of the method for manufacturing a photomask of the present invention is characterized in that the light-shielding portions are arranged in a matrix form at intervals from each other, and the translucent light is formed in a region between the adjacent light-shielding portions. unit.

By using a photomask in which the light-shielding portions are arranged in a matrix at intervals, as shown in this embodiment, and a semi-transmissive portion is formed in an area between adjacent light-shielding portions, a line pattern having a fine portion can be formed. The pattern arranged in a grid pattern can be applied to a wide range of technical fields represented by display devices.

Another embodiment of the method for manufacturing a photomask of the present invention is characterized in that the line pattern is a black matrix.

According to this aspect, a refined black matrix having a width of 2 μm to 10 μm that is urgently desired by the industry can be provided.

One embodiment of the method for manufacturing a color filter of the present invention is a method for manufacturing a color filter, which is characterized in that it is performed by exposing a photosensitive material disposed on a color filter substrate Performing a development process to form a black matrix having a fine portion with a line width of 2 μm to 10 μm and a peripheral region surrounding the black matrix, and including the following steps: irradiating the photomask with exposure light to expose the photosensitive material, and The photomask is provided with a transfer pattern by patterning a light-shielding film and a translucent film respectively provided on the photomask substrate, and the transfer pattern includes a light-shielding portion, a translucent portion corresponding to the black matrix, And a light-transmitting portion that surrounds the light-shielding portion and the translucent portion and corresponds to the peripheral region, and the width of the translucent portion is larger than the fine portion of the black matrix; and the photosensitive material after exposure It develops to form the said black matrix.

According to this aspect, by making the width of the semi-transmissive portion of the mask larger than the fine portion of the black matrix, a black matrix including fine portions with a line width of 2 μm to 10 μm, and a black matrix surrounding the black matrix can be reliably formed. Color filters in the surrounding area.

With the mask of the present invention, it is possible to suppress an increase in equipment investment and a decrease in production efficiency, and it is possible to reliably form a line pattern having a fine portion with a line width of 2 μm to 10 μm and a peripheral region surrounding the line pattern. The manufacturing method of the present invention using the photomask can suppress an increase in equipment investment and a decrease in production efficiency, and can reliably manufacture a black matrix including a fine portion having a line width of 2 μm to 10 μm, and a peripheral region surrounding the black matrix. Color filters.

10‧‧‧Exposure device

20‧‧‧light source unit

30‧‧‧Mask stage

40‧‧‧Workbench

50‧‧‧Gap adjustment mechanism

60‧‧‧XYZθ stage

BM‧‧‧ Black Matrix

BM1‧‧‧Line 1

BW‧‧‧Peripheral area

G‧‧‧ Clearance

GS‧‧‧Pixel Section

H‧‧‧Translucent

H1‧‧‧The first translucent part

H2‧‧‧Second translucent part

K‧‧‧ opening

L1‧‧‧First line

L2‧‧‧ 2nd line

M‧‧‧Photomask

Q‧‧‧Transmission Department

Qz‧‧‧Photomask Substrate

S‧‧‧Shading Department

T‧‧‧ transfer pattern

Wb‧‧‧Width

WK‧‧‧ color filter substrate

Ws‧‧‧Width

hm‧‧‧ translucent film

km1‧‧‧ photosensitive material film

km1'‧‧‧ pattern

km2‧‧‧ photosensitive material film

km2'‧‧‧ pattern

sm‧‧‧shading film

FIG. 1 is a view of a transfer pattern of a photomask viewed from above.

Fig. 2 (a) is a cross-sectional view of the mask of Fig. 1 cut along the line X-X ', Fig. 2 (b) is an enlarged view of a part of the cross-sectional view, and Fig. 2 (c) shows the use of the mask and borrowing Color filter from close exposure A cross-sectional view of a black matrix formed on a light sheet substrate.

3 (a) to (f) are views showing a specific example of a method for manufacturing a photomask of the present invention.

FIG. 4 is a diagram showing a schematic configuration of an exposure apparatus for proximity exposure.

FIG. 5 is a diagram showing the results of a simulation performed to verify the effect of the photomask of the present invention.

FIG. 6 is a diagram showing an example of a color filter substrate for a liquid crystal display device.

The present invention relates to a photomask for forming a fine pattern on a substrate by a photolithography method, especially a line pattern having a fine portion with a line width of 2 μm to 10 μm, and a method for manufacturing a substrate using the photomask. The substrate manufactured using the photomask of the present invention can be applied to various display devices typified by a liquid crystal display device, a plasma display device, and an organic EL display device, or various types related to MEMS (Micro Electro Mechanical Systems) Machines, etc.

Here, in the following description, the present invention will be described by taking a case where it is applied to a color filter substrate for a liquid crystal display device as an example.

One embodiment of the photomask of the present invention is a photomask, which uses a negative-type photosensitive material disposed on one surface of an exposed substrate as a color filter substrate for a liquid crystal display device, and is subjected to proximity exposure. After the development, a black matrix having a fine portion of 2 μm to 10 μm is formed.

Here, the proximity exposure has the advantage that the mask is not contaminated compared to the contact exposure in which the photomask is brought into contact with the object to be transferred, and is also different from the lens projection stepper method and mirror projection. Compared with the reduced projection exposure of the stepper method, there is no need for an expensive optical system, so there is an advantage that the cost of the device can be reduced. The mask in this embodiment is used for a close-type exposure person, and can form a black matrix of a color filter finely.

A color filter forming substrate for a liquid crystal display device corresponds to each pixel of R (red), G (green), and B (blue), and a thickness corresponding to each pixel electrode is provided on a transparent substrate. A thin red filter, a green filter, and a blue filter with a degree of about 1 μm. Between each of the filters, a black matrix is arranged in such a manner that the incident light does not leak from the gaps between the filters and reduce the contrast of the liquid crystal display.

FIG. 6 is an example of a color filter substrate for a liquid crystal display device, which includes a pixel portion GS including a color filter (R, G, B) and a black matrix BM, and a peripheral region BW surrounding the pixel portion. These structures can be formed on a color filter substrate by using a photomask shown in FIG. 1 below.

As shown in FIG. 6, the black matrix BM is a second line extending in parallel in the longitudinal direction such that each of the first line portions L1 extending parallel to each other in the longitudinal direction is spaced apart from each other and a second line extending in parallel in the lateral direction with an interval of each other. Each of the parts L2 is arranged so as to intersect, and is formed so as to cross a plurality of lines in a lattice pattern as a whole. A peripheral region BW is formed around the black matrix BM. In this embodiment, the line width of the first line portion L1 constituting the black matrix BM is 2 μm to 10 μm, and the line width of the second line portion L2 is 8 μm to 30 μm.

Next, an embodiment of the photomask of the present invention is shown in FIG. 1. FIG. 1 is a view of a transfer pattern of a photomask when viewed from above, showing a part of the photomask. Fig. 2 (a) is a cross-sectional view of the mask of Fig. 1 cut along the line X-X ', Fig. 2 (b) is an enlarged view of a part of the cross-sectional view, and Fig. 2 (c) shows the use of the mask and borrowing A cross-sectional view of a black matrix formed on a color filter substrate by proximity exposure. Fig. 3 is a view showing a specific example of a method for manufacturing a photomask of the present invention. FIG. 4 is a diagram showing a schematic configuration of an exposure apparatus for proximity exposure. FIG. 5 is a diagram showing the results of a simulation performed to verify the effect of the photomask of the present invention.

As shown in FIG. 1, the mask in this embodiment is a three-stage mask provided with a transfer pattern including a light-shielding portion S, a semi-light-transmitting portion H, and a light-transmitting portion Q. In the photomask, a transfer pattern T is provided by patterning a light-shielding film and a translucent film provided on the photomask substrate Qz, and the transfer pattern T includes a light-shielding portion S, A linear translucent portion H that transmits a portion of the exposed light and a ring-shaped translucent portion Q that surrounds the light-shielding portion S and the translucent portion H and transmits substantially all of the exposed light. The translucent portion H corresponds to the black matrix described above BM. As the annular light-transmitting portion Q, its width is formed to be significantly larger than that of the semi-light-transmitting portion H, and corresponds to the above-mentioned peripheral region BW. The transfer pattern of the photomask will be described below.

As shown in FIG. 1, the photomask of the present invention includes: light-shielding sections S, which are respectively formed in a rectangular shape, and are arranged in a matrix at intervals; each semi-light-transmitting section H is between each of the light-shielding sections S. And arranged in a grid pattern so as to fill the gap; and a ring-shaped light-transmitting portion Q that surrounds the light-shielding portion S and the semi-light-transmitting portion H. The width of the annular light-transmitting portion Q is formed larger than each of the semi-light-transmitting portions H.

In the photomask shown in FIG. 1, the width of the semi-transmissive portion H is different in the vertical direction and the horizontal direction. That is, as shown in FIG. 1, each of the translucent portions H includes each of the first translucent portions H1 corresponding to the first line portion L1 of the black matrix BM and the second lines of the black matrix BM. Each of the second translucent portions H2 of the portion L2. Each of the first semi-light-transmitting portion H1 and the second semi-light-transmitting portion H2 is orthogonal to each other, and the width of each of the second semi-light-transmitting portion H2 is larger than that of each of the first semi-light-transmitting portion H1. Further, as shown in FIG. 2, the width of the first translucent portion H1 is larger than the first line portion L1 of the black matrix BM. Although not shown, the width of the second translucent portion H2 is larger than the second line portion L2 of the black matrix BM. Such a photomask of the present invention is effective when a black matrix having a line width different from that in the vertical direction and the horizontal direction is manufactured.

Embodiments of the photomask of the present invention will be further described. As shown in FIG. 2 (a), by patterning a light-shielding film in close contact with the photomask substrate Qz on the photomask substrate Qz, each of the light-shielding portions S formed in a rectangular shape is alternated with each of the openings K It is arranged on the ground, and a patterned translucent film is provided corresponding to each of the openings K, thereby forming a first translucent portion H1 (translucent portion H). A light-transmitting portion Q is formed outside the light-shielding portion S and the translucent portion H by removing the light-shielding film and the translucent film to expose the surface of the mask substrate.

As for the light-shielding portion S, as shown in FIG. 2, only a light-shielding film may be formed on the mask substrate Qz. Although not shown, a light-shielding film and a translucent film may be laminated on the mask substrate Qz. Further, in the example shown in FIG. 2, the semi-transmissive film is patterned so as to correspond to each of the openings K, but it is not necessarily patterned in this manner. That is, as shown in FIG. 3 (f) Generally, the semi-transparent film is patterned in such a manner that only a region corresponding to the translucent portion of the semi-transparent film is removed.

As shown in Fig. 2 (b), which enlarges the first translucent portion H1 of the photomask, and Fig. 2 (c), which enlarges the first line portion BM1 of the black matrix formed on the corresponding color filter substrate. The width Ws of the first translucent portion H1 is wider than the width Wb of the first line portion BM1 formed on the black matrix of the color filter substrate.

As shown in the graph of FIG. 5, the exposure light passing through the opening of the mask is affected by the diffraction of light, so that the light intensity (light amount) decreases as it approaches the end of the opening. Therefore, if the width of the first translucent portion H1 (the width of the opening K) is set to the same size as the width Wb of the first line portion BM1 of the black matrix to be formed, near the end of the opening K , The influence of the diffraction of light becomes larger, so that the exposure amount to the photosensitive material is reduced. Therefore, the amount of light in the vicinity of the end of the opening K does not reach the threshold value for photosensitizing the photosensitive material, the hardening degree of the photosensitive material decreases, and the width of the formed black matrix becomes smaller than Wb.

On the other hand, if the width Ws of the first translucent portion H1 is made wider than the width Wb of the first line portion BM1 of the formed black matrix as in this embodiment, that is, the width of the opening K is made wider. Even if the amount of the area where the photosensitive material is not sufficiently photosensitive is equal to or more than that, even if diffraction of light occurs, the area that can obtain a sufficient amount of light to be photosensitive by the photosensitive material (that is, the area near the center) can be used for exposure. Furthermore, by using a semi-transmissive film and appropriately adjusting the amount of exposure light irradiated to the area where the black matrix is formed, a black matrix of the first line portion BM1 having a desired width in a range of 2 μm to 10 μm can be formed. That is, the first line portion BM1 of a desired width can be formed by appropriately selecting the light transmittance of the translucent film and adjusting the width dimension of the portion where the photosensitive material is sufficiently photosensitive.

On the other hand, if only the exposure light amount to the area corresponding to the first line portion BM1 of the black matrix is adjusted, for example, the output of the light source or a filter can be reduced to reduce the amount of light incident on the mask. However, in this case, the amount of light sensitive to the light transmitting portion Q does not reach the threshold value for light-sensitive photosensitive material, so that the peripheral region BW cannot be properly formed. Problem. Therefore, both of the first line portion BM1 and the peripheral region BW with a width of 2 μm to 10 μm can be reliably formed only by using a translucent film.

In addition, if the width Ws of the first semi-light-transmitting portion H1 is within the range described later, the intensity of the exposed light may be increased due to the effect of diffraction. In this case, in order to sufficiently obtain the intensity of the exposed light in the semi-transmissive portion, both the first line portion BM1 and the peripheral region BW can be appropriately hardened.

As in this embodiment, when exposure is performed in a region where a sufficient amount of exposure light (preferable contrast) can be obtained, it has the following effects, even when the interval between the photomask and the color filter substrate varies. In this case, unevenness in line width of the black matrix can also be suppressed. This aspect will be described later using FIG. 5.

If the width Ws of the first translucent portion H1 and the width Wb of the first line portion BM1 of the black matrix are further described in detail, it is preferable that Ws and Wb satisfy the relationship of the following formula (1).

Formula (1); 1.2 ≦ Ws / Wb ≦ 3

By satisfying the above formula (1), even if diffraction of light occurs, it is possible to perform exposure using a region that can obtain a sufficient amount of photosensitive light (preferable contrast), and the use of a semi-transmissive film can appropriately adjust the irradiation to the color filter. The amount of light on the sheet substrate forms the first line portion BM1 with a desired width in the range of 2 μm to 10 μm. Furthermore, since the amount of light irradiated to the area where the first line portion BM1 is formed is adjusted using a semi-transmissive film, the first line portion BM1 can be reliably formed, and a sufficient amount of light can be irradiated to the light transmitting portion Q, thereby reliably forming a surrounding area. A peripheral region BW of the pixel portion GS.

On the other hand, when the value of Ws / Wb is less than 1.2, the width of the first line portion BM1 of the predetermined black matrix may not be obtained due to the influence of the diffraction of light. In addition, when the amount of light passing through the opening K is lower than the amount of exposure incident on the mask, the amount of transmitted light will further reduce the amount equivalent to the transmissivity of the translucent film. Therefore, in actual manufacturing processes, there are ) Increase, which leads to the disadvantage of reduced production efficiency.

On the other hand, when the value of Ws / Wb exceeds 3, even if the opening K is set to half In the transmission state, since the original width of the aerial image becomes too wide, it is difficult to form the first line portion BM1 of the black matrix.

If other numerical examples are given, the width Ws of the first translucent portion H1 and the width Wb of the first line portion BM1 of the black matrix are as follows. That is, since the width Wb of the first line portion L1 of the black matrix BM formed on the color filter substrate is 2 μm to 10 μm, the width Ws of the first translucent portion H1 becomes 2.4 μm to 30 μm.

In addition, the transmissivity of the semi-transmissive film that transmits the exposed light is preferably in the range of 30 to 70%, and more preferably in the range of 40 to 60%. The distance between the photomask and the color filter substrate is preferably adjusted to a range of 40 μm to 300 μm, and further preferably adjusted to a range of 100 μm to 150 μm.

A mask substrate, a semi-transmissive film, and a light-shielding film constituting the mask of this embodiment will be described in detail. As the mask substrate, for example, a substrate that is transparent to light exposed to light, such as synthetic quartz, soda lime glass, or alkali-free glass, can be used. The exposure light used in the photomask of the present invention is continuous light having a broad spectrum with a wavelength spanning a range of 300 nm to 450 nm.

Semi-transparent film is made of metal silicide containing metal and silicon, such as molybdenum silicide (MoSi), tantalum silicide (TaSi), titanium silicide (TiSi), tungsten silicide (WSi), or their oxides , Nitride, oxynitride, etc. In this embodiment, the translucent film is a molybdenum silicide film laminated on the light-shielding film. The translucent film is preferably a MoSi film, a MoSi ₂ film, or a MoSi ₄ film, but may be a MoSiO film, a MoSiN film, a MoSiON film, or the like.

The light-shielding film is formed on a substrate from, for example, a chromium (Cr) -based material having an etching selectivity to a metal silicide. The light-shielding film is, for example, a CrN film, a CrC film, a CrCO film, a CrO film, a CrON film, or a laminated film thereof.

Fig. 3 shows an example of a method for manufacturing the photomask shown in Fig. 1.

As shown in FIG. 3 (a), a light-shielding film sm and a photosensitive material film km1 are sequentially formed on the mask substrate Qz. The photosensitive material is a photoresist used as an etching mask for patterning a light-shielding film. For example, a positive photoresist can be used. Here is the case of using a positive photoresist Bright.

The photosensitive material film km1 is irradiated with an electron beam or laser light to a portion where an opening is to be formed, and then the photosensitive material film is immersed in a developing solution to dissolve the photosensitive material film of the portion irradiated with the electron beam or laser light. Thus, as shown in FIG. 3 (b), a portion corresponding to the semi-transmissive portion and the translucent portion is removed, and a pattern km1 'is formed on the photosensitive material film.

Then, as shown in FIG. 3 (c), the pattern km1 'of the above-mentioned photosensitive material film is used as a mask, for example, the light-shielding film is removed by etching and the unnecessary photosensitive material film is peeled off, thereby forming a light-shielding film. Opening.

Next, as shown in FIG. 3 (d), a semi-transmissive film hm and a photosensitive material film km2 are sequentially formed on the patterned light-shielding film S.

Then, by removing only the photosensitive material film corresponding to the light-transmitting portion Q, exposure and development are performed using an electron beam or laser light, as shown in FIG. 3 (e), to form a pattern km2 'on the photosensitive material film. Here, the patterning is performed by removing only the area corresponding to the light-transmitting portion Q of the translucent film, but as shown in FIG. 2, the translucent film can also be formed in a manner corresponding to each of the openings. Patterned.

Thereafter, as shown in FIG. 3 (f), the pattern km2 'of the photosensitive material film is used as a mask, the translucent film is etched, and the unnecessary photosensitive material film is peeled off.

In this way, a transfer pattern formed by patterning a light-shielding film in close contact with the substrate is formed. The transfer pattern includes each of the light-shielding portions S that shield the exposed light, and is provided with a pattern formed by covering the light-shielding film. The translucent portion H of the translucent film of each of the openings, and the translucent portion Q that exposes the surface of the mask substrate.

Furthermore, regarding the patterned translucent film after the step shown in FIG. 3 (f), the translucent film of the portion overlapping the light-shielding film can be left as it is (the state of FIG. 3 (f)), It is also possible to remove the translucent film by leaving a margin equivalent to the margin of the alignment error (the form shown in FIG. 2).

For the photomask of the present invention, by using the exposure apparatus for proximity exposure shown in FIG. 4 Then, the negative-type photosensitive material coated on the color filter substrate of the liquid crystal display element is subjected to proximity exposure, so that the exposed negative-type photosensitive material is hardened, as shown in FIG. 2 (c) and FIG. 6. Black matrix.

The exposure device 10 shown in FIG. 4 includes a light source unit 20 including a discharge lamp, a condenser, a mirror, and various lenses, such as an ultra-high pressure mercury lamp that emits light containing ultraviolet rays having a wavelength of 300 nm to 450 nm. Further, the light including ultraviolet light emitted from the discharge lamp is emitted from the light source unit 20 through the optical member. The exposure device 10 further includes a mask stage 30 for mounting. A fixed mask M; a work stage 40 for fixing a workpiece (transferred body) WK such as a color filter substrate; a gap adjustment mechanism 50 for adjusting a gap between the mask and the workpiece; and an XYZθ stage 60, It adjusts the position of the workpiece.

A method for manufacturing a color filter in which a black matrix is formed on a color filter substrate through a photomask of the present invention will be described. The manufacturing method of the color filter of the present invention is to expose the negative-type photosensitive material coated on the color filter substrate, make the photosensitive material harden, and then develop it to form the one shown in FIG. 6. Black matrix.

First, the photomask M of the present invention is mounted on the exposure device 10 shown in FIG. 4, and the gap G between the photomask M and the color filter substrate WK as the object to be transferred is adjusted to a range of 40 μm to 300 μm. It is preferable to adjust to the range of 100 micrometers-150 micrometers. Then, a photosensitive material is coated on the color filter substrate by a method such as slit coating.

Here, the photosensitive material is a negative photosensitive material, and the following can be used.

As the negative-type photosensitive material in the present invention, a photosensitive resin in which a pigment, carbon, metal particles, or the like is dispersed can be considered. This system is already known as a patterning method using a pigment dispersion method, and detailed description is omitted. To briefly explain, as the above-mentioned photosensitive material, those containing a coloring agent and a monomer having a reactive functional group, or those containing a polymer, a photopolymerization initiator that polymerizes them by exposure, and a solvent are preferred. . In addition, additives such as a dispersant and a surfactant may be contained. As the colorant, pigment, carbon particles, metal particles, and the like are used.

Using the exposure apparatus shown in FIG. 4, the photosensitive material coated on the color filter substrate is irradiated with light from the photomask substrate side of the photomask through the photomask of the present invention shown in FIG. 1. Proximity exposure. The exposed light is irradiated to the photosensitive material coated on the color filter substrate through the semi-transmissive portion in the mask, so that the exposed area of the photosensitive material exposed to light is hardened. Then, the photosensitive material is developed, and a black matrix is formed on the color filter substrate as shown in FIGS. 2 (c) and 6.

(Result of simulation of the photomask of the present invention)

Next, in order to verify other effects of the present invention, simulations as described below were performed. The simulation results are shown in FIG. 5. The simulation conditions are as follows.

<Example: Photomask of the present invention>

． Width of translucent part; 11.0μm

． Transmittance of translucent film; 60%

Here, the width of the translucent portion refers to the width of the opening provided with the translucent film as shown in Ws of FIG. 2.

<Comparative Example: Previous Binary Mask>

． Width of light transmitting part; 6.0μm

． No translucent film

Here, the binary mask refers to a second-order mask in which a light-shielding film on a mask substrate is patterned, and a light-shielding portion and a light-transmitting portion are formed on the mask substrate.

<The same matters as in Examples and Comparative Examples>

． The wavelength of the exposed light; a mixture of 313nm and 365nm

． Proximity exposure gap; 75 μm, 100 μm, 125 μm, 150 μm, 175 μm, 200 μm, 225 μm

Here, the proximity exposure gap refers to a distance between a transfer pattern of a photomask and a workpiece.

FIG. 5 shows changes in the proximity exposure gap for each of the examples and comparative examples. Light intensity distribution of transmitted light when the above 7 types are 75 μm to 225 μm. Based on the simulation results of FIG. 5, within the range of the proximity exposure gap of 85 μm to 115 μm (with the proximity exposure gap of 100 μm as the center ± 15%), the change rate of light intensity (curves for each of the examples and comparative examples) is calculated. Slope in the figure). As a result, the change rate of the light intensity in the mask of the example was 8.3%, and the change rate of the light intensity in the mask of the comparative example was 28.2%. That is, it can be seen that, compared with the mask of the comparative example, in the case where the gap of the proximity exposure is changed, the light intensity change rate is smaller.

In this way, the color filter of the photomask of the present invention is used which has a wider width than the first line portion of the black matrix formed on the color filter substrate and transmits a part of the exposed light. The manufacturing method is extremely effective in the case of performing proximity exposure. That is, as described above, even when the method for manufacturing a color filter of the present invention changes in a variety of manners in the proximity exposure gap, the change rate of the light intensity irradiated to the photosensitive material is small. Therefore, even in the case where the proximity exposure gap changes in various ways, the light intensity changes less with respect to the photosensitive material, so the line width of the first line portion of the black matrix formed on the color filter substrate can be suppressed. Uneven.

Claims (8)

A photomask is characterized in that it is used to form a line pattern having a fine portion with a line width of 2 μm to 10 μm, and a peripheral area surrounding the line pattern, and includes: a light-shielding portion; a semi-transmissive portion, which corresponds to The line pattern; and a light-transmitting portion that surrounds the light-shielding portion and the semi-light-transmitting portion and corresponds to the peripheral area; the semi-light-transmitting portion is configured to fill the space between the light-shielding portions and has a transmission A film having a characteristic in a range of 30 to 70% and having a width larger than that of the above-mentioned fine portion of the line pattern. For example, in the photomask of claim 1, when the width of the fine portion of the line pattern is set to Wb and the width of the translucent portion is set to Ws, the above Wb and Ws satisfy the following relationship: 1.2 ≦ Ws / Wb ≦ 3. The photomask of claim 1 is used for proximity exposure. The mask of claim 2 is used for proximity exposure. The photomask according to any one of claims 1 to 4, wherein the light-shielding portions are arranged in a matrix form at intervals from each other, and the semi-light-transmitting portion is formed in a region between the adjacent light-shielding portions. The photomask of any one of claims 1 to 4, wherein the line pattern is a black matrix. The mask of claim 5, wherein the line pattern is a black matrix. A method for manufacturing a color filter, which is characterized by forming a fine portion having a line width of 2 μm to 10 μm by exposing a photosensitive material disposed on the color filter substrate and then performing a development process. The black matrix and the surrounding area of the black matrix include the following steps: The photosensitive material is exposed by irradiating the mask with exposure light. The mask is provided with a transfer pattern by patterning a light-shielding film and a translucent film provided on the mask substrate, respectively. The light-shielding portion includes a light-transmitting portion corresponding to the black matrix and a light-transmitting portion surrounding the light-shielding portion and the semi-light-transmitting portion and corresponding to the peripheral area. The light-transmitting portion is used to fill the light-shielding portion. A film structure having a characteristic of a transmission range of 30 to 70% and having a width larger than that of the fine portion of the black matrix; and developing the photosensitive material after exposure to form the black matrix.