JP2008065139A - Grayscale mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grayscale mask having a plurality of translucent regions and capable of giving uniform average illuminance from each translucent region upon exposure. <P>SOLUTION: The grayscale mask comprises a transparent substrate, a light-shielding film formed on the transparent substrate, and a translucent film formed on the transparent substrate, and has a transmissive region where the transparent substrate is exposed, a light-shielding region where the light-shielding film is formed on the transparent substrate, and a translucent region where only the translucent film is formed on the transparent substrate. An adjustment region to adjust the average illuminance from each translucent region to be uniform is formed within the translucent region and/or in the periphery of the translucent region. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gradation mask suitably used for halftone exposure in the manufacturing process of a display device or the like.

  For example, as shown in FIG. 11, the gradation mask is formed on the transparent substrate 1, the semitransparent film 3 that transmits the exposure light formed on the transparent substrate 1 with a desired transmittance, and the semitransparent film 3. And a light-shielding film 2 that substantially shields the exposure light. This gradation mask adjusts the amount of light transmitted by the translucent film 3, the light-transmitting area c where the transparent substrate 1 is exposed, the light-shielding area a that does not substantially transmit light by the light-shielding film 2, and the translucent film 3. And a semi-transparent region b, and gradation can be obtained by the difference in transmittance (see Patent Document 1). Such a gradation mask is used in, for example, two-stage etching used in the TFT array process.

  However, when a plurality of semi-transparent regions are formed in such a gradation mask, although each semi-transparent region is formed using a semi-transparent film having the same average transmittance, In some cases, the average illuminance from each semi-transparent region differs depending on the shape, the type of the region where the semi-transparent region is adjacent, and the like. For example, as shown in FIG. 12A, semi-transparent regions b and b ′ having different sizes are formed on the transparent substrate 1 using a semi-transparent film having a transmittance of 50% so as to be adjacent to the transmissive region c. In this case, the illuminance from the semi-transparent region b having a large area is about 50%, whereas the average illuminance from the small translucent region b ′ is 50% or more. For example, as shown in FIG. 12B, semi-transparent regions b and b ′ having different sizes are formed on the transparent substrate 1 using a semi-transparent film having a transmittance of 50% so as to be adjacent to the light shielding region a. When formed, the illuminance from the semi-transparent region b having a large area is about 50%, whereas the average illuminance from the small translucent region b ′ is 50% or less. This is a phenomenon caused by diffraction or interference of exposure light. When the area of the semi-transparent area is small, the average illuminance is high in the area corresponding to the semi-transparent area adjacent to the transmission area, and adjacent to the light-shielding area. In the region corresponding to the semi-transparent region, the average illuminance is low. Therefore, when the photosensitive resist is exposed and developed using a gradation mask, there is a problem that the thickness of the photosensitive resist remaining in the region corresponding to each translucent region is not uniform.

JP 2002-189280 A

  Therefore, it is desired to provide a gradation mask that has a plurality of translucent regions and can make the average illuminance from each translucent region uniform during exposure.

  The present invention includes a transparent substrate, a light-shielding film formed on the transparent substrate, and a translucent film formed on the transparent substrate, wherein the transparent substrate is exposed on the transparent substrate. A gradation mask having a light-shielding region provided with the light-shielding film and a plurality of semi-transparent regions provided only with the semi-transparent film on the transparent substrate, wherein the average illuminance from each semi-transparent region is uniform There is provided a gradation mask characterized in that an adjustment region for conversion into a semi-transparent region and / or an outer periphery of the semi-transparent region is formed.

  According to this invention, since the said adjustment area | region is formed, it becomes possible to adjust and equalize the average illumination intensity from each translucent area | region. Therefore, when the photosensitive resist is exposed and developed using the gradation mask of the present invention, the film thickness of the photosensitive resist remaining in the region corresponding to the translucent region can be made uniform. .

  In the said invention, the said adjustment area | region can be made into the area | region where the said transparent substrate was exposed. This is because the average illuminance from the translucent region can be adjusted high.

  Moreover, in the said invention, the said adjustment area | region can also be made into the area | region in which the said light shielding film was formed. This is because the average illuminance from the translucent region can be adjusted to be low.

  According to the present invention, it is possible to obtain a gradation mask in which the average illuminance from each translucent region is uniform during exposure.

  Hereinafter, the gradation mask of the present invention will be described. The gradation mask of the present invention has a transparent substrate, a light-shielding film formed on the transparent substrate, and a translucent film formed on the transparent substrate, wherein the transparent substrate is exposed, A gradation mask having a light-shielding region in which the light-shielding film is provided on a transparent substrate and a plurality of semi-transparent regions in which only the semi-transparent film is provided on the transparent substrate. The adjustment region for making the average illuminance uniform is formed inside the semitransparent region and / or on the outer periphery of the semitransparent region.

  The gradation mask of the present invention includes, for example, a transparent substrate 1, a light shielding film 2 formed on the transparent substrate 1, and a half formed on the transparent substrate 1, as shown in the sectional view of FIG. It is a gradation mask having a transparent film 3. Further, for example, as shown in the plan view of FIG. 1B, the light shielding region a in which the light shielding film 2 is formed, the plurality of semitransparent regions b in which the semitransparent film 3 is formed, and the transparent substrate 1 are exposed. Adjustment for adjusting the average illuminance from each semi-transparent region in the semi-transparent region c, the outer periphery of the semi-transparent region c, or the inner and outer periphery of the semi-transparent region c. Region d is formed. Note that when the photosensitive resist exposed with the gradation mask is developed, the adjustment area d is not resolved. The adjustment area is formed on the outer periphery of the translucent area, not only when the adjustment area is formed on the entire outer periphery of the translucent area, but also on the outer periphery of the translucent area. This includes cases where

  As described above, in a general gradation mask, the average illuminance from each semi-transparent region varies depending on the shape of the semi-transparent region, the type of region adjacent to the semi-transparent region, and the like. Therefore, when the photosensitive resist is exposed and developed using the gradation mask, there is a problem that the film thickness of the photosensitive resist remaining in the region corresponding to the translucent region is not uniform.

  On the other hand, in the present invention, since the adjustment area is formed inside or on the outer periphery of the translucent area, the translucent area or translucent area may be formed when the translucent area is formed in various patterns or sizes. Even in the case where a pattern in which areas are adjacent to each other and a pattern in which a light shielding area and a semitransparent area are adjacent to each other are mixed, the average illuminance from each semitransparent area can be made uniform. . Therefore, when the photosensitive resist is exposed and developed using the gradation mask of the present invention, the film thickness of the photosensitive resist remaining in the region corresponding to the translucent region can be made uniform. The photosensitive resist can be used for various patterning, used as various members, and the like.

The exposure mask of the present invention is suitably used in the production of color filters and TFT substrates used in liquid crystal display devices, and usually has a translucent region width of 10 μm or less, particularly 5 μm or less, particularly 4 μm or less. This is particularly useful for the gradation mask. This is because such a gradation mask tends to cause the above-described problems. The lower limit is generally about 0.5 μm, which is the resolution limit when forming various members of the liquid crystal display device.
Hereinafter, the gradation mask of the present invention will be described in detail for each configuration.

1. Adjustment Area First, the adjustment area formed in the gradation mask of the present invention will be described. The transmittance adjustment region formed in the gradation mask of the present invention has a function of adjusting an average illuminance from a semi-transparent region to be described later, and is formed to make the average illuminance of a plurality of semi-transparent regions uniform. It is an area. The adjustment region may be provided to increase the average illuminance of the translucent region, or may be provided to reduce the average illuminance of the translucent region. It is formed by appropriately selecting according to the average illuminance of each translucent region.

  An example of a method for determining the type, shape, line width, etc. of the adjustment area will be described. First, a gradation mask of the present invention and a similar calculation mask are designed except that the adjustment area is not provided, and the average illuminance from each translucent area of the calculation mask is simulated and calculated. Thereafter, a semi-transparent region where the average illuminance is not within the target range is selected, and the required adjustment amount of the average illuminance is calculated. From the obtained result, the type of the adjustment region to be formed is determined. That is, when the average illuminance is low, an adjustment area for increasing the average illuminance is selected, and when the average illuminance is high, an adjustment area for decreasing the average illuminance is selected. Thereafter, the shape and line width of the adjustment region to be formed are optimized by the simulation. The adjustment area may be formed in all the semi-transparent areas, or may be formed only in a part of the semi-transparent areas. Moreover, as a simulator used for the simulation which calculates the said average illumination intensity and optimization of an adjustment area | region, a commercially available optical simulator, for example, SOLID (brand name: Sigma C company make) etc. are mentioned.

  Here, when the average illuminance of the translucent area is increased, the adjustment area is usually an area where the transparent substrate is exposed. This is because the adjustment region can be easily formed without forming other members, and the gradation mask can be efficiently formed. When the adjustment region is a region where the transparent substrate is exposed, the adjustment region can be formed by patterning the semitransparent film formed in the semitransparent region.

  When the average illuminance of the translucent area is lowered, the adjustment area is usually an area where a light shielding film similar to the light shielding film formed in the light shielding area described later is formed. This is because the adjustment region and the light shielding region described later can be formed at a time, and the gradation mask can be formed efficiently. When the adjustment region is a region where the light shielding film is formed, the adjustment region can be formed by patterning the light shielding film formed in the light shielding region.

  Further, the adjustment region is formed inside, on the outer periphery, or on the inner and outer periphery of the translucent region, and the shape thereof can be determined by simulation as described above. In the present invention, for example, as shown in FIG. 1B, it may be formed linearly on the entire outer periphery of the translucent region b or a part of the outer periphery, and for example, as shown in FIG. It may be formed in a broken line shape or a dot shape on the entire outer periphery or a part of the outer periphery of the translucent region b. Further, for example, as shown in FIG. 3, it may be formed in a stripe shape inside the semi-transparent region b, and for example, in an island shape inside the semi-transparent region b as shown in FIG. It may be formed. A combination of these may also be used.

  Further, the width of the adjustment region may be a width that is not resolved at the time of development, and is appropriately selected depending on the shape of the translucent region, the numerical aperture of the exposure machine used for exposure, and the like, as described above. It can be determined by simulation.

  The numerical aperture of the exposure machine used for exposure of the gradation mask of the present invention can usually be about 0.06 to 0.12.

  The width of the adjustment region is a width that is not resolved, and is usually 2 μm or less, preferably 1 μm or less. In addition, when the adjustment region is formed in a stripe shape, an island shape, or the like in the translucent region, it is preferable that the adjustment region whose width is equal to or less than the above value is scattered.

  In the present invention, in the case where there is a variation in average illuminance depending on the part within each semi-transparent region, the adjustment region as described above is used in order to uniformize the illuminance within each semi-transparent region. It may be provided.

2. Next, the light shielding region formed in the gradation mask of the present invention will be described. The light shielding region in the gradation mask of the present invention may be a region where a light shielding film that does not substantially transmit exposure light is formed on the transparent substrate, and is a region where only the light shielding film is formed on the transparent substrate. Alternatively, it may be a region where a translucent film and a light shielding film are laminated. When the semi-transparent film and the light-shielding film are laminated, the light-shielding film may be formed between the transparent substrate and the semi-transparent film, or formed on the semi-transparent film formed on the transparent substrate. The stacking order is not particularly limited. The shape of the light shielding region is appropriately selected according to the application of the gradation mask.

  Here, in the present invention, the transmittance of the light-shielding film is usually preferably 0.1% or less. The transmittance can be calculated by measuring the transmittance of the light shielding region using the transmittance of the transparent substrate used for the gradation mask as a reference (100%) and averaging the obtained values. As a device for measuring the transmittance, an ultraviolet / visible spectrophotometer (for example, Hitachi U-4000) or a device having a photodiode array as a detector (for example, Otsuka Electronics MCPD) can be used.

  As the light shielding film, a light shielding film generally used for a photomask can be used. Examples of the film include chromium, chromium oxide, chromium nitride, chromium oxynitride, molybdenum silicide, tantalum, aluminum, silicon, silicon oxide, silicon oxynitride, and titanium. In addition, a nickel alloy, a cobalt alloy, a nickel-cobalt alloy, and films of these oxides, nitrides, oxynitrides, oxynitride carbides, and the like can also be used.

  Among them, chromium-based films such as chromium, chromium oxide, chromium nitride, and chromium oxynitride; Ni—Cu—Ti and Ni—Ta—Cu—Ti mainly composed of nickel, and oxides, nitrides, and oxynitrides thereof Nickel alloy films such as oxides, oxynitride carbides, etc .; Co—Cu—Ti and Co—Ta—Cu—Ti mainly composed of cobalt, and oxides, nitrides, oxynitrides, oxynitride carbides, etc. of these Cobalt alloy-based films: Ni-Co-Cu-Ti mainly composed of nickel and cobalt, and nickel-cobalt alloy-based films such as oxides, nitrides, oxynitrides, and oxynitride carbides thereof are preferably used. The chromium film may be a single layer or may be a laminate of two or more layers.

  The film thickness of the light shielding film is not particularly limited and is appropriately selected depending on the type of the light shielding film, etc. For example, in the case of a chromium film, it is preferably about 50 nm to 150 nm.

  As a method for forming the light shielding film, for example, a physical vapor deposition method (PVD) such as a sputtering method, an ion plating method, or a vacuum vapor deposition method is used.

3. Translucent Area Next, the translucent area in the gradation mask of the present invention will be described. The semi-transparent region in the gradation mask of the present invention is a region where a semi-transparent film is formed on a transparent substrate. In the present invention, a plurality of semi-transparent regions are formed in the gradation mask. The shape of the translucent region is appropriately selected according to the application of the gradation mask.

  The transmittance of the translucent film is preferably in the range of 10% to 60%, particularly in the range of 20% to 50% at a wavelength of 250 nm to 600 nm. If the transmittance is less than the above range, the difference in transmittance between the semi-transparent region and the light-shielding region may be difficult to occur, and if the transmittance exceeds the above range, the translucent region and the transparent region where the substrate is exposed This is because it may be difficult to produce a difference in transmittance. The method of measuring the transmittance can be the same as the method described above.

  The translucent film used in the present invention is appropriately selected depending on the type of gradation mask and the like, and is not particularly limited, but preferably has etching selectivity with respect to the light shielding film. This is because when manufacturing a gradation mask, only the semipermeable membrane can be selectively etched, which is preferable in terms of manufacturing efficiency and the like. Also, there is a defect in the pattern of the semi-transparent film due to misalignment, particles (such as dust) at the time of forming the semi-transparent film, or peeling, dirt adhesion, patterning unevenness, etc. at the time of patterning the semi-transparent film. Even if it occurs, if the semi-transparent film has etching selectivity with respect to the light-shielding film, only the semi-transparent film can be removed, so that only the semi-transparent film can be removed and recycled. It is.

  Examples of such a translucent film include chromium, molybdenum silicide, tantalum, aluminum, titanium, silicon, nickel, nickel alloy, cobalt, cobalt alloy, and oxide, nitride, and carbide films thereof. .

  Among them, chromium-based films such as chromium, chromium oxide, chromium nitride, chromium oxynitride, and chromium oxynitride carbide; Ni—Cu—Ti and Ni—Ta—Cu—Ti mainly composed of nickel, and oxides thereof, Nickel alloy films such as nitride, oxynitride, oxynitride carbide, etc .; Co—Cu—Ti and Co—Ta—Cu—Ti mainly composed of cobalt, and oxides, nitrides, oxynitrides thereof, Cobalt alloy film such as oxynitride carbide; Ni—Co—Cu—Ti mainly composed of nickel and cobalt, and nickel-cobalt alloy film such as oxide, nitride, oxynitride, oxynitride carbide, etc. Preferably there is.

  In the nickel alloy film, the cobalt alloy film, and the nickel-cobalt alloy film, the etching rate can be controlled by adjusting the contents of elements other than nickel and cobalt as main components. For example, when the content of elements other than nickel and cobalt increases, the etching rate decreases. In the oxynitride carbide film, the etching rate can be controlled by adjusting the carbon content. Specifically, the etching rate decreases as the carbon content increases.

  As a preferable combination of the semitransparent film and the light shielding film, for example, when a nickel alloy film is used for the semitransparent film and a chromium film is used for the light shielding film, or a chromium film is used for the semitransparent film, For example, a nickel alloy film is used. In the case of this combination, a high etching selectivity can be realized.

  The film thickness of the translucent film may be any film thickness that can achieve the desired transmittance, and is appropriately selected depending on the type of the translucent film. For example, in the case of a chromium film, the thickness is preferably about 5 to 50 nm, in the case of a chromium oxide film, preferably about 5 nm to 150 nm, and in the case of a nickel alloy film or a cobalt alloy film, about 20 nm to 120 nm. It is preferable that

  Since the transmissivity of the translucent film varies depending on the film thickness, the desired transmissivity can be obtained by controlling the film thickness. Further, when the translucent film contains oxygen, nitrogen, carbon or the like, the transmittance varies depending on the composition. Therefore, the desired transmittance can be realized by simultaneously controlling the film thickness and the composition. For example, the transmittance increases as the oxygen content increases, and similarly, the transmittance increases as the nitrogen content increases. Nitrogen has a small effect of increasing the transmittance as compared with oxygen. Therefore, when the transmittance is adjusted more finely, the nitrogen content may be adjusted.

  As a method for forming the translucent film, for example, a physical vapor deposition method (PVD) such as a sputtering method, an ion plating method, or a vacuum vapor deposition method is used. For example, when forming a chromium oxynitride chromium carbide film using a sputtering method, a reactive gas sputtering method using a Cr target by introducing a carrier gas such as Ar gas, oxygen (carbonic acid) gas, or nitrogen gas into the reactor. Thus, a chromium oxynitride carbide carbide film can be formed. At this time, the composition of the chromium oxynitride carbide film can be controlled by controlling the flow rates of Ar gas, oxygen (carbonic acid) gas, and nitrogen gas.

4). Next, the transmissive region in the gradation mask of the present invention will be described. The transmissive region in the gradation mask of the present invention is a region where the transparent substrate is exposed. The shape of the transmission region is appropriately selected according to the use of the gradation mask.

  As the transparent substrate used in the present invention, a substrate generally used for a photomask can be used. As the transparent substrate, there is no flexibility such as optically polished low expansion glass such as borosilicate glass and aluminoborosilicate glass, quartz glass, synthetic quartz glass, Pyrex (registered trademark) glass, soda lime glass, white sapphire, etc. A transparent rigid material, or a transparent flexible material having flexibility such as a transparent resin film or an optical resin film can be used. Among them, quartz glass is a material having a small coefficient of thermal expansion, and is excellent in dimensional stability and characteristics in high-temperature heat treatment.

5. Gradation mask The gradation mask of the present invention is not particularly limited as long as the above-described light-shielding region, translucent region, transmissive region, and adjustment region are formed. These regions may be formed.

  Further, the gradation mask of the present invention can be used for manufacturing various products manufactured through an exposure process, such as a lithography method. Among these, the effects of the present invention can be utilized to the maximum when used for manufacturing a display device such as a liquid crystal display device, an organic EL display device, or a plasma display panel, particularly for manufacturing a large display device.

  Specifically, the drain electrode and the channel in the thin film transistor (TFT) are simultaneously formed, the spacer and the alignment control protrusion are simultaneously formed in the liquid crystal display device or the color filter for the liquid crystal display device, and the liquid crystal display device or the color filter for the liquid crystal display device. Simultaneous formation of spacer and overcoat layer, simultaneous formation of spacers of different heights in a liquid crystal display device or color filter for liquid crystal display devices, coloring for transmissive part in a color filter for translucent liquid crystal display devices or translucent liquid crystal display devices And simultaneous formation of a white pattern overcoat layer and a red / green / blue pattern overcoat layer in an organic EL display device or a color filter for an organic EL display device. .

  In addition, the size of the gradation mask is appropriately adjusted according to the application. For example, when used for manufacturing a display device such as a liquid crystal display device or an organic EL display device, the size is 300 mm × 400 mm to 1,600 mm. It can be about x1,800 mm.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be specifically described using examples and comparative examples.

[Example 1]
(Light-shielding film patterning)
A regular mask blank was prepared in which a chromium film (light-shielding film) was formed to a thickness of 100 nm on an optically polished 5-inch synthetic quartz substrate (transparent substrate). On the mask blank, a commercially available photoresist (ip-3500 manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied at a thickness of 600 nm, baked on a hot plate heated to 120 ° C. for 15 minutes, and then with a laser drawing apparatus for photomask, A light shielding film intermediate pattern (a pattern excluding a semi-transparent region) was drawn. Next, development was performed with a dedicated developer (NMD3 manufactured by Tokyo Ohka Kogyo Co., Ltd.) to obtain a resist pattern for a light shielding film. Next, using the resist pattern for the light shielding film as an etching mask, the chromium film (light shielding film) was etched, and the remaining resist pattern was peeled off, thereby patterning the light shielding film in the middle pattern of the light shielding film. A commercially available cerium nitrate wet etchant (MR-ES manufactured by The Inktec Co., Ltd.) was used for etching the chromium film.

(Formation of translucent film)
Next, the substrate on which the light-shielding film is patterned is subjected to pattern dimension inspection, pattern defect inspection, pattern correction as necessary, and after being washed well, a chromium oxynitride carbide film (translucent film) is sputtered under the following conditions Was formed. The film thickness of the chromium oxynitride carbide film (translucent film) was 35 nm.
<Film formation conditions>
・ Gas flow ratio Ar: CO ₂ : N ₂ = 1: 0.5: 0.5
・ Power: 1.5kW
・ Gas pressure: 3mTorr

(Patterning of light shielding film and translucent film)
Next, a commercially available photoresist (ip-3500, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on the translucent film at a thickness of 600 nm on the chromium oxynitride carbide film, and baked on a hot plate heated to 120 ° C. for 15 minutes. Subsequently, the pattern of the semitransparent film region was drawn with a laser drawing apparatus and developed with a dedicated developer (NMD3 manufactured by Tokyo Ohka Kogyo Co., Ltd.) to obtain a resist pattern. Next, using the resist pattern as a mask, the semitransparent film and the light shielding film were etched with a commercially available cerium nitrate wet etchant (MR-ES manufactured by The Inktec Co., Ltd.) to form the semitransparent film region and the light shielding region. Etching was performed on the translucent film and the light shielding film. Finally, the remaining resist was peeled off, and after undergoing inspection processes such as pattern dimension inspection and pattern defect inspection, pattern correction was performed as necessary to obtain a gradation mask.
The translucent film had a transmittance of 40%. Further, each pattern of the above regions is a pattern as shown in FIG. 5A, and is a 10 μm × 10 μm rectangular translucent region b, 4 μm × 4 μm rectangular translucent region b ′, and transmitted light. It has the area | region c and the light-shielding area | region a.
FIG. 6 shows the result of simulating the average illuminance from the translucent regions b and b ′ with SOLID (trade name: manufactured by Sigma C). As is apparent from FIG. 6, the illuminance of the translucent region b ′ of 4 μm × 4 μm is higher than that of the translucent region b of 10 μm × 10 μm.
Therefore, when the shape and width of the adjustment region were simulated by SOLID (trade name: manufactured by Sigma C), for example, as shown in FIG. 5B, 1 μm was formed at the four corners of the 4 μm × 4 μm translucent region b ′. By forming the adjustment region d composed of the corner light-shielding film 2, the illuminance of each translucent region (b and b ′) can be made uniform. FIG. 7 shows the result of simulating the illuminance when the adjustment region is formed in the 4 μm × 4 μm translucent region with SOLID (trade name: manufactured by Sigma C).
In accordance with this, a gradation mask was formed by the same method as described above so that the 4 μm × 4 μm semi-transparent areas had adjustment regions made of 1 μm square light-shielding films at the four corners.

[Evaluation]
A glass substrate having a size of 100 mm × 100 mm and a thickness of 0.7 mm was prepared, and a commercially available photoresist (AZP1350 manufactured by AZ Electronic Materials) was applied on the glass substrate at a thickness of 1500 nm and heated to 110 ° C. Bake on plate for 90 seconds. Then, it exposed on the following conditions through the gradation mask which does not have the said adjustment area | region, and the gradation mask which has the said adjustment area | region.
<Exposure conditions>
・ Exposure amount: 160 mJ / cm ²
Subsequently, it developed with the exclusive developer (AZ Developer made from AZ Electronic Materials), and the resist pattern was obtained. The cross-sectional shape of the formed pattern was observed with a scanning electron microscope, and the dimensions were measured. The results are shown in Table 1.

上記調整領域を有する４μｍ×４μｍのパターンのレジスト残膜量と、１０μｍ×１０μｍのパターンのレジスト残膜量をほぼ一致させることができた。

The resist residual film amount of the pattern of 4 μm × 4 μm having the adjustment region and the residual resist film amount of the pattern of 10 μm × 10 μm could be substantially matched.

[Example 2]
For example, as shown in FIG. 8A, a translucent region b in which a translucent film 3 is formed in a rectangular shape of 5 μm × 5 μm in a transmissive region c, and 5 μm in a rectangular light-shielding region a of 8 μm × 8 μm. A gradation mask having a semitransparent region b ′ in which the semitransparent film 3 was formed in a rectangular shape of × 5 μm was formed. The forming material and the forming method of the translucent film formed in the translucent region and the light shielding film formed in the light shielding region are the same as those in the first embodiment.
FIG. 9 shows the result of simulating the average illuminance from the translucent regions b and b ′ with SOLID (trade name: manufactured by Sigma C). As is apparent from FIG. 9, the illuminance from the translucent area b ′ surrounded by the light shielding area a (illuminance indicated by HT in Cr in the figure) and the translucent area b surrounded by the transmission area c (FIG. 9). Among them, the illuminance from the illuminance indicated by HT in Qz is greatly different.
Therefore, when the shape and width of the adjustment area are simulated by SOLID (trade name: manufactured by Sigma C), for example, as shown in FIG. 7B, the adjustment area is in a translucent area b ′ surrounded by the light shielding area a. As a result, the illuminance of each semi-transparent region (b and b ′) can be made uniform by forming eight 1 μm square adjustment regions d where the transparent substrate 1 is exposed. The result of having simulated the illumination intensity from the semi-transparent area | region which formed the said adjustment area | region by SOLID (brand name: Sigma C company make) is shown in FIG. Accordingly, the gradation mask of the present invention having the adjustment region was formed. The adjustment region was formed by patterning the translucent film.

[Evaluation]
A photosensitive resist was exposed and developed in the same manner as in Example 1 except that the development time was set to 50 s to obtain a resist pattern. The cross-sectional shape of the formed pattern was observed with a scanning electron microscope, and the dimensions were measured. The results are shown in Table 2.

上記調整領域を有する８μｍ×８μｍの遮光領域に囲まれた半透明領域５μｍ×５μｍのパターンのレジスト残膜量と、遮光領域に囲まれていない半透明領域５μｍ×５μｍのパターンのレジスト残膜量をほぼ一致させることができた。

Residual film amount of semi-transparent area 5 μm × 5 μm pattern surrounded by 8 μm × 8 μm light-shielding area having the adjustment area and resist residual film amount of semi-transparent area 5 μm × 5 μm pattern not surrounded by light-shielding area Could be matched.

It is a figure for demonstrating the gradation mask of this invention. It is a figure for demonstrating the gradation mask of this invention. It is a figure for demonstrating the gradation mask of this invention. It is a figure for demonstrating the gradation mask of this invention. It is a figure for demonstrating the Example of the gradation mask of this invention. It is a graph for demonstrating the Example of the gradation mask of this invention. It is a graph for demonstrating the Example of the gradation mask of this invention. It is a figure for demonstrating the Example of the gradation mask of this invention. It is a graph for demonstrating the Example of the gradation mask of this invention. It is a graph for demonstrating the Example of the gradation mask of this invention. It is a figure for demonstrating the conventional gradation mask. It is a figure for demonstrating the conventional gradation mask.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Light-shielding film 3 ... Semi-transparent film a ... Light-shielding area b ... Semi-transparent area c ... Transmission area d ... Adjustment area

Claims (3)

A transparent substrate; a light-shielding film formed on the transparent substrate; and a translucent film formed on the transparent substrate, wherein the transparent substrate is exposed; the light-shielding film on the transparent substrate; A gradation mask having a light-shielding region provided, and a plurality of semi-transparent regions in which only the semi-transparent film is provided on the transparent substrate,
A gradation mask characterized in that an adjustment region for making the average illuminance from each of the semi-transparent regions uniform is formed in the semi-transparent region and / or the outer periphery of the semi-transparent region.   The gradation mask according to claim 1, wherein the adjustment region is a region where the transparent substrate is exposed.   The gradation mask according to claim 1, wherein the adjustment region is a region where the light shielding film is formed.

Images