JP2003029393A - Mask, pattern forming method using the same, and lithography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mask capable of forming steps different from each other in layer thickness and excellent in intrasurface uniformity in a resist by a general exposure system. SOLUTION: The photomask 1 used for exposing a photosensitive resin layer 7 stacked on a substrate 6 to form a latent image in the layer 7 consists of a transparent support 2 and opaque light shielding parts 3 and a transmissive part 4 disposed on the support 2, and the transmissive part 4 has a first transmissive wavelength selective region 4a and a second transmissive wavelength selective region 4b different from each other in the wavelength region of transmitted light.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mask used for manufacturing a semiconductor device, for example, and a lithographic method using the mask. Further, the present invention relates to a semiconductor device manufactured by the lithography method and a liquid crystal display device including the same.

The present invention also relates to a mask used for manufacturing a reflection plate and pattern formation using the mask. Further, the present invention relates to a reflector manufactured by the pattern forming method, and a liquid crystal display device including the same.

[0003]

2. Description of the Related Art Conventionally, a so-called gradation mask (halftone mask) has been used in a photolithography process in a semiconductor manufacturing process. This gradation mask has a function of gradually changing the transmittance of light to be transmitted within one mask. To describe the specific structure of the gradation mask, first, a light-shielding metal thin film is provided as a light-shielding portion on a glass substrate. Further, there is provided a transmissive part that adjusts the layer thickness of the metal thin film for each region and makes the transmissivities of the transmitted lights different from each other. When the photoresist is exposed using the photomask having such a structure, it is possible to irradiate the photoresist while varying the exposure amount for each region within the surface of the photoresist. As a result, a stepped pattern is formed.

Further, SID'00 DIGEST, 1006-9 discloses a photomask having a mask pattern below the resolution limit of an exposure apparatus. It is described that if this photomask is used, it is possible to perform exposure while making a difference in exposure amount for each region within the surface of the photoresist. As a result, it is described that after development, the thickness is different for each region, and it is possible to form a pattern having a step.

Here, in the above gradation mask,
Extremely high light-shielding property such as Cr (that is, low transmittance)
A metal film made of a material is used as a light shielding film. Further, in order to control the amount of exposure in the transmissive part, the metal film with a partially thin layer is used. The exposure dose is controlled by adjusting the layer thickness within the range of several tens of liters to several hundred liters. However, in this range, the dependency of the light transmittance on the layer thickness is extremely high, so that the transmittance of the exposure light greatly differs even if a slight error occurs. Therefore, even if it is desired to perform patterning so as to have the same layer thickness within the photoresist surface, it is difficult to precisely control the layer thickness of the metal film, so that the exposure amount varies. As a result, the patterned photoresist is not formed to have a desired film thickness and becomes non-uniform. As described above, in the conventional gradation mask, there is a problem that it is extremely difficult to obtain a gradation property of a uniform exposure amount within the mask surface.

In the photomask having a mask pattern below the resolution limit, the size of the pattern below the resolution limit is masked in order to ensure the uniformity of the exposure amount after passing through the photomask. It is necessary to make it uniform in the plane. However, it is difficult to secure the uniformity of the pattern size in this order, and therefore it is extremely difficult to obtain the uniformity of the exposure amount within the mask surface.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide a step having different layer thicknesses and having excellent in-plane uniformity. The purpose is to provide a mask that can be formed on a resist by a collective exposure method.

Another object of the present invention is to provide a pattern forming method for patterning a resist into a desired shape using the mask, and a lithography method for patterning an arbitrary thin film into a desired shape.

Further, a method of manufacturing a semiconductor device using the lithography method, a semiconductor device obtained by the manufacturing method, a method of manufacturing a reflector using the lithography method, and a reflector manufactured by the manufacturing method. A liquid crystal panel comprising the semiconductor element or a reflector,
Another object is to provide a liquid crystal display device including the liquid crystal panel.

[0010]

Means for Solving the Problems (Mask) (1) In order to solve the above-mentioned problems, a mask according to the present invention exposes at least one photosensitive resin layer laminated on a substrate, A mask used for forming a latent image on the photosensitive resin layer, wherein the mask comprises a transparent support, and an opaque light-shielding portion and a transparent portion provided on the support. It is characterized in that the transmission part has a plurality of transmission wavelength selection regions in which wavelength regions of transmitted light are different from each other.

The mask having the above-mentioned structure has two mask patterns.
The dimensional information is not transferred as it is to the photoresist as a latent image, but the mask pattern is transferred as the three-dimensional information by providing the mask with the transmission part.

As described above, the transmission part has a plurality of transmission wavelength selection regions in which the wavelength regions of light to be transmitted are different from each other. Then, the transmission wavelength selection region is exposed by changing the wavelength region of light for each exposure region in the photosensitive resin layer. That is, the mask having the above structure is different from the conventional gradation mask that simply adjusts the thickness of the chromium film to control the exposure amount. When the photosensitive resin layer is exposed using a mask having such a structure, for example, the photosensitive resin layer cuts a part of the wavelength region in which the sensitivity is exhibited, thereby controlling the degree of progress of photolysis or photopolymerization. be able to.

Therefore, the depth position where the latent image is formed can be arbitrarily controlled, the exposure contrast can be improved, and the pattern precision in the cross section can be improved. Further, since the exposure amount is not controlled or the exposure is not performed in a dot shape with a mask pattern below the resolution limit, a pattern having a step can be formed so as to have an extremely uniform surface without variation.

In the above structure, at least one of the plurality of transmission wavelength selection regions may be made of a material different from that of the light shielding portion.

(2) In order to solve the above problems, another mask according to the present invention exposes a photosensitive resin layer provided on a substrate to form a latent image on the photosensitive resin layer. A mask used for this purpose, which comprises a transparent support, and an opaque light-shielding portion and a transparent portion provided on the support, wherein the transparent portion is the photosensitive material. It is characterized in that the resin layer substantially transmits light including a wavelength region exhibiting sensitivity, and has a plurality of transmittance control regions having mutually different light transmittances.

By using the mask having the above structure, it is possible to transmit light having a wavelength region optimum for the sensitivity characteristics of the photosensitive resin layer to be exposed and irradiate the photosensitive resin layer. As a result, the exposure efficiency can be improved. Moreover, since the plurality of transmittance control regions having different light transmittances are provided, in the photosensitive resin layer, the exposure amount is different for each region corresponding to each transmittance control region. As a result, the degree of progress of photolysis or photopolymerization of the photosensitive resin differs. As a result, during the development process, a difference in the solubility or the dissolution rate in the developing solution can be produced for each region. That is, the mask pattern can be transferred to the photosensitive resin layer as three-dimensional information.

In the above structure, at least one of the plurality of transmittance control regions is made of a material different from that of the light shielding portion, and the change rate of the transmittance with respect to the thickness is smaller than that of the light shielding portion. It can be made of a material.

In the conventional gradation mask, for example, a part of a chrome film which is usually used as a light-shielding film is provided in the light transmitting portion so that the layer thickness becomes a predetermined thickness. The light transmittance of this chrome film changes significantly even if the layer thickness is slightly different. On the other hand, in the case of the mask having the above-mentioned configuration, the transmittance control region is made of a material in which the rate of change in transmittance that changes depending on the thickness is small, as compared with the transmissive portion in the conventional gradation mask. The transmittance can be easily controlled. Therefore, with the mask having the above structure, the depth position where the latent image is formed is made easier than the conventional mask,
It can be made more convenient than conventional gradation masks.

As a result, in the above structure,
The plurality of transmittance control regions may have different thicknesses so that the light transmittance has a predetermined value, whereby the exposure contrast is improved and the shape control of the step is excellent. A mask can be provided.

Further, in each of the above-mentioned structures, when the light-shielding portion is made of a predetermined metal film, the light-transmitting portion is made of an oxide of a metal forming the metal film, and the layer thickness of the light-transmitting portion is further made. However, it can be set in the range of ½ or more and 4/5 or less of the layer thickness of the light shielding portion.

Further, in the above structure, the metal film may be made of chromium.

Here, in the mask according to the above (1) and (2), the following constituent elements can be further added.

That is, the transmission part in the above (1) and (2) may be configured to include an inorganic oxide. For example, in the conventional gradation mask, the amount of light transmission is controlled by changing the film thickness of the metal chromium film. However, when the transmission part is configured to include an inorganic oxide as in the above configuration, the transmission part can select the transmission wavelength and transmit light.

Here, examples of the inorganic oxide include indium tin oxide, indium oxide, tin oxide, silicon oxide, chromium oxide, titanium oxide, aluminum oxide, yttrium oxide and hafnium oxide. At least one oxide selected from the group consisting of By appropriately selecting or combining these oxides as necessary, the wavelength selectivity of light transmitted through the mask is facilitated, and a desired mask pattern can be transferred to the photosensitive resin layer.

Further, the inorganic oxide is preferably a lower oxide. A lower oxide has better crystallinity, so that the transparency of the transmission part can be improved. As a result, the exposure amount can be reduced and the production cost can be suppressed.

Further, the permeation part in the above (1) and (2) can be configured to contain a halide of an alkaline earth metal. When the transmissive portion is configured to include a halide of an alkaline earth metal, it is possible to control the transmission of light by selecting the transmission wavelength, as in the case of the inorganic oxide described above.

Further, it is preferable that an auxiliary light-shielding portion is provided between the plurality of transmission wavelength selection regions in (1) and (2). In this case, the auxiliary light shielding part is provided as an auxiliary pattern for the main pattern composed of the light shielding part and the transmissive part. The auxiliary light shielding portion as the auxiliary pattern imparts discreteness to the diffracted light generated when transmitting through the mask, and prevents the diffracted lights from interfering with each other. Therefore, it is possible to prevent a peak in the amount of transmitted light from occurring and to suppress the occurrence of pattern defects in the shape after patterning.

(Pattern Forming Method) (1) In order to solve the above-mentioned problems, the pattern forming method according to the present invention forms a photosensitive resin layer on a substrate and interposes the mask of any one of the above-mentioned modes. Then, after forming a latent image of a predetermined shape by exposing the photosensitive resin layer,
By developing the photosensitive resin layer after the exposure, a stepped pattern is formed on the photosensitive resin layer.

According to the above method, it is possible to form a stepped pattern on the photosensitive resin layer by a single exposure.
In addition, the surface of each step can be made uniform and patterned.

(2) In order to solve the above-mentioned problems, another pattern forming method of the present invention is a pattern forming method for performing stepwise patterning on a plurality of photosensitive resin layers laminated on a substrate. A mask having an opaque light-shielding portion and a light-transmitting portion having a plurality of transmission wavelength selection regions in which the wavelength regions of light to be transmitted are different from each other is prepared on the transparent support, and on the substrate, Forming a multilayer structure by laminating a plurality of the photosensitive resin layers having sensitivity to mutually different wavelength regions, and then exposing the plurality of photosensitive resin layers that are the multilayer structure through the mask. To form a latent image on the surface layer or from the surface layer to a predetermined layer in each region of the multilayer structure, and further develop the exposed multilayer structure to form a pattern having at least one step. Characteristic To.

According to the above method, the photosensitive resin layers laminated on the substrate show different sensitivities from each other.
Depending on the wavelength range of the exposed light, the formation position of the latent image can be controlled only on the surface layer or from the surface layer to a predetermined layer.

For example, the surface layer in the multilayer structure is sensitive only to a specific i-line, and the layers below the surface layer are g-line and h-line.
Taking the case of showing sensitivity to a line as an example, when it is desired to remove a part of the surface layer, the transmission wavelength selection region for transmitting only the i-line light is aligned with this region. Exposure. At this time, the exposure light reaches the lower layer, but the lower layer shows sensitivity only to g-line and h-line, so that only the surface layer undergoes photopolymerization or photolysis.
As a result, the three-dimensional information of the mask pattern is transferred to the multi-layer structure, which enables pattern formation with steps.

That is, according to the above method, it is possible to obtain a precise cross-sectional shape of the pattern rather than forming a pattern on a single-layer photosensitive resin layer which is sensitive to only a specific wavelength. It is possible to further improve the degree of patterning.

In the above structure, a dry film resist layer can be formed on at least one of the plurality of photosensitive resin layers.

When a plurality of photosensitive resin layers are laminated on the substrate, the organic solvent contained in the material of the photosensitive resin layers is
For example, the lower photosensitive resin layer may be dissolved. In this case, the surface of the surface layer becomes uneven, and the shape after patterning lacks the flatness of the surface. On the other hand, the material of the dry film resist does not inherently contain an organic solvent. Therefore, by forming a dry film resist layer in at least one of the plurality of photosensitive resin layers as in the above-mentioned configuration, the lower photosensitive resin layer is not dissolved, and as a result, the surface flatness is improved. Can be improved and patterning can be performed.

(3) In order to solve the above-mentioned problems, still another pattern forming method of the present invention is a pattern forming method in which a photosensitive resin layer provided on a substrate is patterned with steps. A mask having an opaque light-shielding portion and a transmission portion having a plurality of transmission wavelength selection regions in which wavelength regions of light to be transmitted are different from each other is prepared on a transparent support, and a mask is provided on the substrate. After forming a photosensitive resin layer containing at least two kinds of photosensitive resins having different sensitivities to different wavelength regions, the photosensitive resin layer is exposed to light through the mask. A latent image is formed in each region to a predetermined depth position, and the exposed photosensitive resin layer is further developed to form a stepped pattern.

According to the above method, since the photosensitive resin layer contains at least two kinds of photosensitive resins having different sensitivities from each other, the exposure depends on the wavelength range of the exposed light. It is possible to control to which depth position the latent image is formed for each region.

For example, a photosensitive resin layer composed of a positive photosensitive resin sensitive only to i-line and a positive photosensitive resin sensitive to g-line and h-line will be described as an example. Is the street. In this case, only the photosensitive resin sensitive to the i-line is photodecomposed in the exposed region where the i-line is irradiated.
Therefore, during development, only the photosensitive resin sensitive to the i-line is removed, so that the photosensitive resin layer is removed to a predetermined depth position in the exposed area. On the other hand, in the exposure area irradiated with g-line, h-line and i-line, g-line, h-line and i-line are exposed.
Since the photosensitive resin sensitive to the rays is photolyzed, all the photosensitive resin layers are removed in the exposed area. As a result, a stepped pattern can be formed.

That is, according to the above method, it is possible to obtain a precise cross-sectional shape of the pattern rather than forming a pattern on a single-layer photosensitive resin layer which is sensitive to only a specific wavelength. It is possible to further improve the degree of patterning.

(Lithography Method) (1) In order to solve the above-mentioned problems, a lithography method according to the present invention is a lithography method for patterning an arbitrary thin film provided on a substrate into a predetermined shape. After forming a resist layer on the substrate through the thin film, through the mask of any one of the above-described mode, by exposing the resist layer, to form a latent image of a predetermined shape,
By developing the resist layer after exposure, patterning with a resist step is performed on the resist layer, the thin film is etched, and the resist layer after development is peeled off.

According to the above method, a pattern having a resist step can be formed on the resist by one exposure. Moreover, the surface of each resist step can be made uniform to form a highly accurate resist step in the cross section. Therefore, according to the above method of etching the thin film using the resist thus patterned as a mask, it is possible to form a thin film having a uniform film surface and good cross-section accuracy.

(2) In order to solve the above-mentioned problems, another lithographic method of the present invention is a lithographic method of patterning an arbitrary thin film provided on a substrate into a predetermined shape and having transparency. A mask having an opaque light-shielding portion and a transmission portion having a plurality of transmission wavelength selection regions in which wavelength regions of light to be transmitted are different from each other is prepared on the support, and wavelength regions different from each other are provided on the substrate. After forming a multi-layer structure by laminating a plurality of the resist layers showing sensitivity to, for each region of the multi-layer structure by exposing the plurality of resist layers that are the multi-layer structure through the mask Forming a latent image on the surface layer or from the surface layer to a predetermined layer, and developing the exposed multilayer structure to form a pattern having at least one step, and etching the thin film. More, to form a pattern having a step in its thin film, characterized by further peeling off the resist layer.

According to the above method, it is possible to perform patterning while further improving the precision in the cross section of the resist step, as compared with the case where patterning is performed on a single-layer resist. Therefore, according to the above method of etching such a thin film using such a resist as a mask, it is possible to form a thin film having a uniform film surface and a better cross-sectional precision.

In the above structure, at least one layer of the plurality of resists may be a dry film resist layer.

Since the material of the dry film resist does not contain an organic solvent, it is possible to prevent the lower resist layer from being dissolved by providing the dry film resist on a normal resist layer. As a result, the flatness of the surface can be improved and patterning can be performed.

(3) In order to solve the above-mentioned problems, still another lithographic method of the present invention is a lithographic method of patterning an arbitrary thin film provided on a substrate into a predetermined shape, which is transparent. A mask having an opaque light-shielding portion and a transmission portion having a plurality of transmission wavelength selection regions in which the wavelength regions of light to be transmitted are different from each other is prepared on the support, and wavelengths different from each other are provided on the substrate. After forming a resist layer containing at least two kinds of photosensitive resins having sensitivity to the region, the resist layer is exposed through the mask to reach a predetermined depth position for each region of the resist layer. A latent image is formed, and the exposed resist layer is developed to form a pattern having at least one resist step, and the thin film is etched to form the thin film. Forming a pattern having a step, characterized in that it further peeling off the resist layer.

According to the above method, since the photosensitive resin layer contains at least two kinds of photosensitive resins having different sensitivities from each other, if the wavelength region of the exposure light is made different for each exposure region, the latent image is changed accordingly. The depth position at which the image is formed can also be controlled.

Therefore, it is possible to form a resist step having extremely high precision in the cross section on the resist by a single exposure. Further, since the thin film is etched using the resist patterned in this way as a mask, it is possible to form a thin film having a uniform film surface and good patterning accuracy.

(Method of manufacturing semiconductor device and semiconductor device manufactured by the same) In order to solve the above-mentioned problems,
A method of manufacturing a semiconductor device of the present invention is characterized in that a semiconductor device is formed on a substrate by using any one of the above-described lithography methods.

With this method, patterning of a predetermined thin film forming a semiconductor element can be performed with a reduced number of steps. Moreover, since the precision of the cross-sectional shape of the patterned thin film is extremely high, the thin film can be formed without causing variations in device characteristics among semiconductor devices.

In order to solve the above-mentioned problems, the semiconductor element of the present invention is a semiconductor element manufactured by the method for manufacturing a semiconductor element described above, wherein a part of the semiconductor element has a cross-sectional shape. It is characterized by having a stepped shape.

According to the above structure, the semiconductor element can be manufactured by using the method for manufacturing a semiconductor element including the above-described lithography method, so that a semiconductor element having no variation in element characteristics between elements can be provided. Here, "a part of the semiconductor element is stepwise in its cross-sectional shape" means that a part of the thin film forming the semiconductor element has a step.

Further, in the above-mentioned structure, the stepwise portion in the cross-sectional shape can be made up of two or more thin films.

Further, in each of the above structures, a thin film transistor or a thin film diode can be formed as the semiconductor element.

(Reflector Manufacturing Method and Reflector Manufactured Therewith) In order to solve the above problems, the reflector manufacturing method of the present invention uses the pattern forming method according to any one of the above-mentioned embodiments. By forming a stepped pattern on the photosensitive resin layer, a plurality of irregularities are formed on the substrate, and a light reflection film is further formed on the substrate provided with the irregularities. Characterize.

According to the above method, since the plurality of concave and convex portions formed on the substrate are formed by the above-described pattern forming method, the shape can be controlled so that the reflection characteristic becomes optimum. As a result, it is possible to manufacture a reflector having excellent reflection characteristics.

In order to solve the above-mentioned problems, the reflector of the present invention is characterized by being manufactured by the above-described method for manufacturing a reflector. As a result, it is possible to provide a reflection plate whose reflection characteristics are uniform in the plane.

In order to solve the above-mentioned problems, another reflector of the present invention is a semi-transmissive reflector produced by the above-mentioned method for producing a reflector, wherein the substrate is transparent. The light reflecting film has a region for reflecting light and a region for transmitting light, which is not provided with the light reflecting film. With such a structure, it is possible to provide a semi-transmissive reflection plate whose reflection characteristics are uniform in the plane.

(Liquid Crystal Panel and Liquid Crystal Display Device Equipped with It) In order to solve the above-mentioned problems, the liquid crystal panel of the present invention is characterized by including the above-mentioned semiconductor element. With this configuration, since the semiconductor element having no variation in element characteristics among the elements is provided, it is possible to provide a liquid crystal panel having uniform color reproducibility in the display screen and good display characteristics.

In order to solve the above-mentioned problems, the liquid crystal panel of the present invention is characterized by including the above-mentioned reflection plate. According to this configuration, since the reflection plate having the in-plane uniform reflection characteristics is provided, it is possible to provide a liquid crystal panel capable of bright display.

In order to solve the above problems, the liquid crystal display device of the present invention is characterized by including each of the above-mentioned liquid crystal panels and a drive circuit for driving the liquid crystal panels. As a result, it is possible to provide a liquid crystal display device which has a uniform color reproducibility on the display screen and is capable of bright display and has excellent display characteristics.

[0062]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following embodiments. Further, in each of the embodiments, the same components are designated by the same reference numerals and detailed description thereof is omitted.

(First Embodiment) The photomask according to the first embodiment is a mask used for patterning a photoresist as a photosensitive resin layer with a resist step by one exposure and development process. Is. Since an ordinary photomask converts two-dimensional information of an exposed pattern into a three-dimensional shape of a resist by a developing process, patterning with steps cannot be performed by one exposure and developing process. On the other hand, in the photomask according to the present embodiment, the three-dimensional information of the mask pattern is added at the time of exposure, and the three-dimensional information is given in the developing process.
Since the pattern is converted into a three-dimensional shape based on the dimension information, patterning with a resist step can be easily performed.

In this embodiment, since the three-dimensional information of the mask pattern is given to the photosensitive resin layer at the time of exposure, the photomask has a light-shielding portion that substantially blocks light and a wavelength of light to be transmitted. And a transmission part having a plurality of transmission wavelength selection regions whose regions are different from each other. By adopting such a configuration, light having different wavelength regions is exposed for each exposure region in the photosensitive resin layer.

First, the specific structure of the photomask will be described. 1A and 1B are schematic cross-sectional views for explaining the photolithography process. FIG. 1A shows a state of exposing a photosensitive resin layer through a photomask, and FIG. 1B shows a photo after development. The state of the resist is shown.

The photomask 1 according to the present embodiment is a mask structure including a glass substrate 2 as a support, a light shielding part 3 and a transmissive part 4 (see FIG. 3A).

As the light shielding portion 3, various conventionally known light shielding films patterned on the glass substrate 2 in a predetermined shape can be used. Specific examples thereof include a single-layer chromium film made of Cr and a low-reflection two-layer film in which a chromium oxide film is further provided on the single-layer chromium film. Whether to use a single-layer chromium film or a two-layer film may be appropriately determined according to mask specifications. In addition to chromium, silicon, molybdenum silicide, or the like can be used. The layer thickness of the light shielding portion 3 may be appropriately set as needed.

The transmission part 4 has a first transmission wavelength selection region 4a for selectively transmitting light in a wavelength region including i-line (365 nm) and deep UV (light in a short wavelength region of 300 nm or less), and g-line ( (425 nm), h-line (406 nm), and i-line (365 nm).
The first transmission wavelength selection region 4a is made of, for example, indium tin oxide (ITO _x ). Second transmission wavelength selection area 4b
Is a space portion excluding the light shielding portion 3 and the first transmission wavelength selection area 4a.

Further, the light shielding portion 3 and the first transmission wavelength selection area 4
The planar shapes of a and the second transmission wavelength selection region 4b are not particularly limited as long as they form a pattern image according to the shape to be patterned.

The photomask 1 having the above structure can be manufactured as follows. FIG. 2 is an explanatory diagram for explaining the method of manufacturing the photomask.

First, as shown in FIG. 2A, a chromium film 21 to be a light shielding portion is formed on the glass substrate 2 by a conventionally known method. Next, a photoresist (not shown) is selectively formed in a predetermined shape on the chromium film 21. Using the photoresist as a mask, the chromium film 21 is irradiated with an electron beam, and the photoresist film is removed. As a result, the light-shielding portion 3 patterned into a predetermined shape can be formed (FIG. 2B).

Next, the ITO film 22 is formed on the glass substrate 2 on which the light shielding portion 3 is formed by a conventionally known method (FIG. 2).
(C)). Further, the photoresist 2 is formed on the ITO film 22.
3 is formed (FIG. 2D), and exposure is performed through a mask (FIG. 2E) to selectively form a predetermined shape. The photoresist is removed by using the photoresist as a mask to irradiate the electron beam (FIG. 2F), and then the photoresist according to the first embodiment is formed (FIG. 2).
(G)).

The photoresist pattern forming method using the photomask 1 having the above-described structure was performed as follows. First, on the substrate 6, a positive photosensitive resin (trade name: OFPR5000, manufactured by Tokyo Ohka Kogyo Co., Ltd.)
Was applied by a spin coating method to form a photoresist 7 (photosensitive resin layer, layer thickness 1.5 μm). This photosensitive resin was sensitive to light in the wavelength range of g-line, h-line and i-line.

Next, the photomask 1 and the substrate 6 are aligned with each other, and the photoresist 7 is inserted through the photomask 1.
The sample was exposed to exposure light (ultraviolet light) 8. As an exposure device for exposure, one having an ultrahigh pressure mercury lamp as a light source was used. The exposure light 8 emitted from the ultra-high pressure mercury lamp is g
Line (426 nm), h line (405 nm) and i line (3
65 nm) has a wavelength peak. The exposure dose is
150mJ / cm ² (UVT integrated light meter UIT-15
0, Ushio Denki Co., Ltd., photoreceiver UVD-S365).

Subsequently, the exposed photoresist 7 was developed. As a result, in the portion corresponding to the first transmission wavelength selection region 4a, the thin film region 11 having a thinner layer thickness than the original photoresist 7 was formed. In addition, in the portion corresponding to the second transmission wavelength selection area 4b, the photosensitive resin was completely removed, and the removal area 12 was formed. As a result, a pattern having a resist step was formed on the photoresist 7 (see FIG. 1B).

The resist step shown in FIG. 1B could be formed for the following reason. First transmitted light 9 transmitted through the first transmission wavelength selection region 4a in the photomask 1
Is light in the i-line and a short wavelength region of 300 nm or less. The second transmitted light 10 transmitted through the second transmission wavelength selection region 4b is the g line and the h line. On the other hand, the photoresist 7 is mainly made of a photosensitive resin having absorption in the g-line, h-line, and i-line regions, and when irradiated with light in these wavelength regions, it is solubilized by photodecomposition, and therefore, during development The part can be dissolved.

Here, in the portion corresponding to the second transmission wavelength selection region 4b, the second transmitted light 10 having wavelength peaks is irradiated to all of the g-line, h-line and i-line, so that all of the photosensitive resin is irradiated. Were removed, and the removed region 12 was formed. On the other hand, in the portion corresponding to the first transmission wavelength selection region 4a, since the i-line and the light in the short wavelength region of 300 nm or less are irradiated, not all of the photosensitive resin is removed, and the portion is not removed. Then, the thin film region 11 having the predetermined thickness and the photoresist 7 remaining was formed. As a result, the resist step 13 shown in FIG. 9B could be formed simultaneously with the patterning.

Further, the photoresist 7 after patterning
In comparison with the one formed by using the conventional gradation mask, the controllability of the cross-sectional shape was excellent, and the surface of the resist step 13 portion could be patterned uniformly. This is because the photomask 1 according to the present embodiment is different from the conventional mask that simply controls the transmittance, and blocks or attenuates light in a specific wavelength range, so that the photosensitive resin in the photoresist 7 is protected. This is because the progress of photolysis is controlled and the depth position is changed by the difference in the progress.

As described above, the first transmission wavelength selection region 4a and the second transmission wavelength selection region 4 in the photomask 1 are
If the wavelength ranges of the light transmitted by b are different from each other, each of them transmits only light of a specific wavelength different from each other or attenuates only light of a specific wavelength. As a result, in each exposed region, only the polymer that is sensitive to the wavelength region of the light irradiated to each photodegrades or photopolymerizes. Therefore, a difference in molecular weight occurs between the exposed regions, and the patterning is formed by dissolving the portion having a small molecular weight. As a result, the photoresist is exposed to 3 times with one exposure.
The dimensional information can be formed as a latent image, and the number of steps can be reduced and the production efficiency can be significantly improved as compared with the conventional exposure which is performed in multiple stages using a plurality of photomasks.

In this embodiment, a photomask in which an ITO _x film is used as the first transmission wavelength selection region 4a and nothing is formed as the second transmission wavelength selection region 4b is taken as an example. explained. However, the present invention is not limited to this, and the first transmission wavelength selection region 4a and the second transmission wavelength selection region 4b may be made of an inorganic oxide. Specifically, in addition to ITO _x , tin (Sn), chromium (Cr),
A metal oxide in which a metal such as titanium (Ti), aluminum (Al), yttrium (Y), and hafnium (Hf) is bound to oxygen, or a nonmetal such as a nonmetal such as silicon (Si) and oxygen is bound. Oxides can also be used. Examples of the tin oxide in the metal oxide include tin monoxide (SnO) and tin dioxide (SnO ₂ ). As chromium oxide, nichrome trioxide (Cr ₂
O ₃ ), chromium trioxide (CrO ₃ ). Examples of titanium oxide include titanium monoxide (TiO), dititanium trioxide (Ti ₂ O ₃ ), and titanium dioxide (TiO ₂ ). As the aluminum oxide, aluminum oxide (Al ₂ O _3). Examples of the yttrium oxide include yttrium oxide (Y ₂ O ₃ ). Examples of hafnium oxide include hafnium oxide (HfO ₂ ). As silicon oxide, silicon dioxide (Si
O ₂ ). The metal oxide or non-metal oxide is preferably a lower oxide having a smaller number of oxygen atoms per metal or non-metal atom. This is because a low-grade oxide has good crystallinity and thus can have excellent transparency.

Furthermore, if the light that can be transmitted through the transmission wavelength selection region is subdivided into multi-stages for each wavelength region by using various kinds of the exemplified inorganic oxides, the amount of information that can be transferred to the photoresist will be dramatically increased. Can be improved. As a result, it is possible to easily form the resist steps in multiple stages.

Furthermore, the present invention is not limited to metal oxides and non-metal oxides, but chlorides of alkaline earth metals such as calcium (Ca), strontium (Sr), etc. can be adopted. . In this case, if the layer thickness is appropriately controlled, it can be carried out similarly to the above-mentioned inorganic oxide.

Further, in the pattern forming method according to the first embodiment, the case where the layer thickness of the photoresist is 1.5 μm has been described as an example. However, about 0.1 μm
If the layer thickness is in the range of 5 μm, by appropriately adjusting the exposure amount and / or the developing time according to the layer thickness,
It is possible to obtain the same effect as that of the first embodiment.

Further, in the first embodiment, the photoresist made of the positive type photosensitive resin has been described, but the present invention can also use the negative type photosensitive resin. As a positive photoresist, OFPR5000 (trade name, Tokyo Ohka Kogyo Co., Ltd.)
For example, PC403 (manufactured by JSR Co., Ltd.) or the like can be used to form a resist pattern having a staircase shape in one exposure.

(Embodiment 2) Another embodiment of the present invention will be described below. The same components as those described in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The photomask according to the second embodiment is different from the photomask according to the first embodiment in that a mask having transmission wavelength selection regions in which the wavelength regions of light to be transmitted are different from each other is used. The difference is that a mask having transmittance control regions having mutually different transmittances is provided. 3A and 3B are schematic cross-sectional views for explaining the photolithography process. FIG. 3A shows a state in which the photoresist is exposed through a photomask, and FIG. 3B shows the state after development. The appearance of the photoresist is shown.

That is, as shown in FIG. 9A, the photomask 31 according to the second embodiment is formed on the glass substrate 2.
This is a light transmittance adjustment type mask structure in which the light shielding portion 3 and the transmission portion 32 are formed in a predetermined shape.

The transmissive portion 32 is made of a material having a smaller rate of change in transmissivity with respect to the film thickness as compared with a metal film such as Cr. Specifically, for example, ITO or the like is adopted. In addition, the transmissive part 32 has a first layer having a different thickness.
It is composed of a transmittance control area 32a and a second transmittance control area 32b. The reason why the layer thicknesses of the first transmittance control region 32a and the second transmittance control region 32b are different is that the light transmittances of the two are different from each other. As a result, the first transmittance control area 32a and the second transmittance control area 3
2b, g line (425 nm), h line (406
nm) and i-line (365 nm) have different transmittances.

Here, the adjustment of the layer thickness is used as a means for providing a plurality of regions having different light transmittances in the transmissive portion 32, by adjusting the film thickness of the chrome film in the conventional gradation mask, for example. It is the same. However, the mask according to the present invention is
The following points clearly differ from the conventional gradation mask using a chromium film, and have a remarkable effect. FIG. 4 is a graph showing the relationship between the film thickness D of a thin film and the light transmittance T (%). In the figure, a curve a shows the case of a thin film made of ITO used in the present embodiment. Curve b
Shows the case of a single-layer chromium film made of chromium used in a conventional gradation mask. As can be seen from the figure, in the case of a single-layer chromium film, it is necessary to change the film thickness within an extremely narrow range of d ₁ to d ₂ to control the transmittance within the range of T _{1 to} T _2. There is. Therefore, even if a slight error occurs in the film thickness, the transmittance greatly changes, and it is difficult to obtain the desired transmittance. On the other hand, in the case of a thin film made of ITO, the transmittance can be controlled by changing the film thickness within a wide range of D _{1 to} D ₂ , and the dependence of the light transmittance on the film thickness is small. . Therefore, it is easy to control the transmittance,
And it can be done precisely.

The light shielding portion 3 and the transmission portion 32 (the first transmittance control area 32a and the second transmittance control area 32b)
The planar shape of is not particularly limited as long as it forms a pattern image according to the shape to be patterned.

With the photomask 31 having the above structure, the amount of transmitted light can be made different in each region of the photoresist corresponding to the first transmittance control region 32a and the second transmittance control region 32b. The mask pattern as the two-dimensional information can be converted into the three-dimensional information and applied as a latent image to the photoresist. As a result, it is possible to easily form a pattern having a resist step on the photoresist.

The photomask 31 having the above structure is manufactured as follows. First, a chromium film is formed on the glass substrate 2 by the same method as described in the first embodiment.
Next, a photoresist is selectively formed in a predetermined shape on the chromium film. Using this photoresist as a mask, the chromium film is irradiated with an electron beam, and the photoresist film is removed. As a result, the light shielding portion 3 having a predetermined film thickness that is patterned into a predetermined shape is formed.

Next, an ITO film is formed on the glass substrate 2 on which the light shielding portion 3 is formed by a conventionally known method. further,
A photoresist is formed on the ITO film. The photoresist is exposed through a mask to selectively form the photoresist in a predetermined shape. Further, the ITO film is irradiated with an electron beam using the photoresist as a mask.
At this time, the film thickness is different for each region corresponding to the first transmittance control region 32a or the second transmittance control region 32b. Subsequently, the photoresist is removed, and the second embodiment
Forming a photomask.

As described above, the first of the photomask 1
Transmittance control area 32a and second transmittance control area 32b
If the light transmittances are different, it is possible to irradiate the photoresist with different light transmission amounts in the respective regions. As a result, three-dimensional information can be formed on the photoresist as a latent image with a single exposure, and the production efficiency can be significantly improved as compared with the conventional exposure that is performed in multiple stages using a plurality of photomasks. Can be improved.

The photomask 31 having the above structure
The method of forming a photoresist pattern using is as follows.

In the same manner as in the first embodiment, a positive type photosensitive resin (trade name: OFPR5000,
A photoresist 7 is formed by coating with Tokyo Ohka Kogyo Co., Ltd. Next, the photoresist 7 is exposed to the exposure light 8 through the photomask 31. Then, the exposed photoresist 7 is developed. As a result, in the portion corresponding to the first transmittance control region 32a, the thin film region 11 having a layer thickness smaller than that of the original photoresist 7 is formed. Also, the second
In the portion corresponding to the transmittance control region 32b, the photosensitive resin is completely removed and the removed region 12 is formed. As a result, a pattern having a resist step 13 can be formed on the photoresist 7 (see FIG. 3B).

Further, the photoresist 7 after patterning
In comparison with the one formed using the conventional gradation mask, the surface including the resist step 13 portion was smooth and the layer thickness of each portion was uniform.

In the photomask according to the second embodiment, the case where ITO _x is used as the constituent material of the transmission part 32 has been described as an example, but the present invention is not limited to this. Not a thing. In addition to ITO _x , for example, a metal such as tin (Sn), chromium (Cr), titanium (Ti), aluminum (Al), yttrium (Y), or hafnium (Hf), or a nonmetal such as silicon (Si) It is also possible to use metal oxides and non-metal oxides bonded with oxygen. Further, the oxide in this case is preferably a lower oxide having a smaller number of constituent oxygen atoms per metal or non-metal atom. This is because the lower oxide has better crystallinity and excellent transparency.

Furthermore, the present invention is not limited to metal oxides and non-metal oxides, but chlorides of alkaline earth metals such as calcium (Ca) and strontium (Sr) can also be adopted. In this case, if the layer thickness is appropriately controlled, it can be similarly carried out.

Further, in the pattern forming method according to the second embodiment, the case where the layer thickness of the photoresist is set to 1.5 μm has been described as an example, but 0.1 μm to 5 μm
If the layer thickness is about the same, it is possible to obtain the same effect as that of the second embodiment by appropriately adjusting the exposure amount and / or the developing time according to the layer thickness.

Further, in the second embodiment, the first
The case where the transmittance control region 32a and the second transmittance control region 32b are made of the same material has been described, but the present invention is not limited to this. That is, the first transmittance control region 32a and the second transmittance control region 32b may be made of different materials.

Further, the light shielding portion 3 is made of a predetermined metal film,
If either the first transmittance control region 32a or the second transmittance control region 32b is made of an oxide of the same metal as the light shielding portion 3, the layer thickness is 1/2 or more of the layer thickness of the light shielding portion 3. It is preferably 4/5 or less. For example, if the layer thickness of the light-shielding portion 3 is 14000Å, the layer thickness of the first transmittance control region 32a is 8000Å, and the layer thickness of the second transmittance control region 32b is 2000Å, it can be carried out similarly to the first embodiment. Is.

(Embodiment 3) Still another embodiment of the present invention will be described below. In addition, the first embodiment
Alternatively, the same components as those described in the second embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the photomask according to the third embodiment, the auxiliary light-shielding portion is provided between the light-transmitting portions having different light transmittances, so that patterning is performed with a uniform layer thickness even in a portion having a resist step. It is a thing. Here, FIG. 5 is an explanatory diagram for explaining a photoresist pattern shape when a photolithography process is performed using a photomask for comparison with the photomask according to the third embodiment. FIG. 3A is a cross-sectional view showing the structure of the photomask, and FIG. 2B is a graph showing the relationship between the amount of light transmitted through the photomask and the exposure position. FIG. 3C is a cross-sectional view showing the photoresist after being exposed using the photomask and further developed. FIG. 6 is an explanatory view for explaining the pattern shape of the photoresist when a photolithography process is performed using the photomask according to the third embodiment, and FIG. It is sectional drawing which shows the structure of a mask, the figure (b) is a graph which shows the relationship of the transmitted light amount of the light which permeate | transmits the said photomask, and an exposure position, and the same figure (c) uses the said photomask. It is sectional drawing which shows the photoresist after exposing and further developing. Figure 7
FIG. 7 is a plan view showing a main part of the photomask according to the third embodiment.

First, the pattern formation in the case of using a photomask in which the transmissive portion is composed of a plurality of regions having different amounts of transmitted light will be described. As shown in FIG. 5A, the photomask 41 is composed of the glass substrate 2, and the light shielding portion 3 and the transmission portion 42 provided on the glass substrate 2. Further, the transmissive part 42 includes a first transmissive region 42a that transmits substantially all of the exposure light and a second transmissive region 42b that transmits the exposure light after attenuating the exposure light to a predetermined transmissivity.

In the photomask 41 having such a configuration, the boundary between the light-shielding portion 3 and the first transmissive region 42a, the boundary between the first transmissive region 42a and the second transmissive region 42b, and the second
Diffracted light is generated at the boundary between the transmissive region 42b and the light shielding portion 3.
As a result of these diffracted lights interfering with each other, an extreme peak of the amount of transmitted light locally occurs depending on the exposure position. Specifically, as shown in the graph of the transmitted light amount distribution in FIG. 5B, between the light blocking portion 3 and the first transmission region 42a, and the first transmission region 42a.
The peak P at which the amount of transmitted light is maximum because the diffracted lights generated between the transmitted region 42a and the second transmitted region 42b interfere with each other.
₁ occurs. Further, the diffracted lights generated between the first transmission region 42a and the second transmission region 42b, and between the second transmission region 42b and the light shielding portion 3 interfere with each other, and a peak P ₂ occurs. Therefore, as shown in FIG. 5C, when the photoresist (photosensitive resin layer) 43 applied on the substrate 6 is exposed through the photomask 41 and then developed, a region corresponding to the second transmission region 42b is formed. Then, the resist hole 44 is formed. On the other hand, in the portion where the resist step 45 is formed, the pinhole 46 is formed at the position where the peak P ₂ appears.
Occurs.

Since such a shape defect in the resist step 45 is caused by the distribution of the transmitted light amount, the transmitted light amount distribution of the main pattern is improved in the third embodiment. From the viewpoint, the above-mentioned pinhole 46
It prevents the occurrence of.

That is, in the photomask 47 according to the third embodiment, the first transmissive region 42a and the second transmissive region 4 are included.
An auxiliary light-shielding portion 48 is provided between the second light source 2b and the second light source 2b (see FIG. 6).
(A)). As a result, as shown in FIG. 6B, the first
The diffracted light generated between the transmissive region 42a and the second transmissive region 42b and between the second transmissive region 42b and the light shielding portion 3 can be made discrete so that interference between the diffracted lights can be suppressed. As a result, the distribution of the amount of transmitted light can be a flat peak P ₃ in the exposure area corresponding to the second transmission area 42b. Therefore, as shown in FIG. 6C, it is possible to form a resist step 45 having no pinhole.

In addition, in the third embodiment, the planar shape of the auxiliary light-shielding portion 48 is a rectangular shape as shown in FIG. Here, the width W of the auxiliary light shielding portion 48 is preferably 4 μm or less. However, this numerical range is due to the resolution limit of the exposure apparatus being 4 μm. Therefore, the width W of the auxiliary light-shielding portion 48 does not depend on the pattern size of the light-shielding portion 3 and the light-transmitting portion 42, and is generally preferably not more than the resolution limit of the exposure apparatus. In addition, the auxiliary light shielding unit 48
In the present embodiment, the length L of the first transparent region 4 is
2a and the second transmission region 42b are matched.

The pattern forming method described above is
It relates to the case where the exposure light of 150 mJ / cm ² is irradiated.
Further, OFPR5000 is used as the photoresist 43.
Is used and the layer thickness is 1.5 μm.

The auxiliary light-shielding portion 48 is the same as in the first embodiment.
In the method of manufacturing a photomask described in 1 above, when the photoresist is formed on the chromium film 21, if the shape corresponding to the auxiliary light shielding portion 48 is also patterned at the same time,
Can be formed.

Further, the auxiliary light shielding portion 48 according to the present embodiment.
Can be applied to the photomask described in the first embodiment or the second embodiment. For example, in the photomask according to the first embodiment, the wavelength regions of the light to be transmitted are different in each transmission wavelength selection region, but some wavelength regions overlap. In such a case, the diffracted lights in the overlapping wavelength regions interfere with each other, and an extreme peak of the amount of transmitted light locally occurs depending on the exposure position, which may cause a pinhole. However,
By providing the auxiliary light shielding part 48 between the transmission wavelength selection regions as in the present embodiment, it is possible to prevent interference between diffracted lights having overlapping wavelength regions, and as a result, the layer thickness at the step portion is reduced. It is possible to make uniform and prevent the generation of pinholes.

(Embodiment 4) In Embodiment 4, a photoresist suitable for the photomask according to Embodiment 1 is used in order to further improve the pattern precision and perform stepped patterning. The patterns were formed in combination. FIG. 8 is a schematic sectional view for explaining a photolithography process according to the fourth embodiment, and FIG. 8A shows a state of exposing a photoresist through a photomask, and FIG. ) Indicates the state of the photoresist after development.

That is, the pattern forming method according to this embodiment is different from each of the above-described embodiments in that the photoresist having the single-layer resist structure is replaced with the first photoresist (hereinafter referred to as the surface layer) on the substrate 6. 1) and a second photoresist (hereinafter, referred to as a lower layer) 52 in this order are used (see FIG. 8).

Each resist layer is made of a photosensitive material having a sensitivity corresponding to the wavelength region of the light transmitted by the first transmission wavelength selection region 4a or the second transmission wavelength selection region 4b in the photomask 1, and both resist layers are formed. Have different wavelength regions showing sensitivity. That is, although the wavelength regions in which both have sensitivity may partially overlap with each other, they have a relationship in which wavelength regions insensitive to each other are mutually present. This makes it possible to supplement the performance of the photoresist in the case of the single-layer resist structure and further improve the precision of the cross-sectional shape of the pattern.

More specifically, the surface layer 51 is a g-line,
It is made of a photosensitive resin that is sensitive to h-line and i-line.
A photochemical reaction is caused to the light transmitted through the transmission wavelength selection region 4b. The lower layer 52 is made of a photosensitive resin having sensitivity to i-line and causes a photochemical reaction with respect to the light transmitted through the first transmission wavelength selection region 4a. The surface layers 51 and the lower layer 52 each have a thickness of about 1.0 μm, but the present invention is not limited thereto.

The exposure light 53 of 200 mJ / cm ² is exposed through the photomask 1 to the multilayer resist structure having the above-mentioned structure. The exposure light 53 is light having a wavelength range including g-line, h-line and i-line.

By the exposure, the first transmission wavelength selection region 4
The first transmitted light 54 transmitted through a is i-line and 300 nm.
Since the light is in the following short wavelength region, only the surface layer 51 undergoes a photochemical reaction to be solubilized. On the other hand, the second transmitted light 55 transmitted through the second transmission wavelength selection region 4b is g-line, h-line and i-line, and therefore both the surface layer 51 and the lower layer 52 undergo a photochemical reaction to be solubilized.

Therefore, in the development by the wet method after exposure,
The etching reaction by the developing solution remains only in the surface layer 51 in the region corresponding to the first transmission wavelength selection region 4a, but also occurs in the lower layer 52 in the region corresponding to the second transmission wavelength selection region 4b. And both underlayer 52 are removed. As a result, a resist step 56 is formed in a region corresponding to the first transmission wavelength selection region 4a,
A resist hole 57 is formed in a region corresponding to the second transmission wavelength selection region 4b.

As described above, if the photomask according to the first embodiment and the multilayer resist are combined to form a pattern, the surface is made uniform and the pattern precision is further improved, and a resist step is formed. It can be patterned.

(Fifth Embodiment) In the pattern forming method according to the fifth embodiment, in the multilayer resist adopted in the fourth embodiment, patterning is performed by replacing the upper layer with a film-like dry resist. Is different.

Since the forming coating liquid for forming the dry resist does not contain an organic solvent, the lower layer made of the photosensitive resin is not dissolved during the coating of the coating liquid. Therefore, it is possible to prevent unevenness from being generated on the surface of the upper layer. As a result, it is possible to form a pattern having a resist step so that the resist surface is prevented from becoming uneven and the surface becomes more uniform.

As the dry resist, a multi-layer resist can be formed by applying a film-shaped photosensitive resin without coating the photosensitive resin.

(Sixth Embodiment) In the pattern forming method according to the sixth embodiment, the single layer resist adopted in the first embodiment is replaced by two types of wavelength regions showing sensitivity different from each other. The difference is that patterning was performed using a photoresist made of a photosensitive resin. FIG. 9 is a schematic cross-sectional view for explaining the photolithography process according to the sixth embodiment, and FIG. 9A shows a state of exposing a photoresist through a photomask, and FIG. ) Indicates the state of the photoresist after development.

First, a photosensitive resin A having sensitivity to i-line and deep UV and a photosensitive resin B having sensitivity to g-line, h-line and i-line are mixed at a predetermined mixing ratio to form a film. A coating liquid was prepared. This coating solution for forming was applied on the substrate 6 by spin coating to form a photoresist 61 (layer thickness: 1.5 μm).

Next, this photoresist 61 was exposed through the photomask 1. At this time, the same exposure apparatus as in the first embodiment was used, and the exposure amount was 150 mJ / cm ² . At the time of exposure, the second transmitted light 10 transmitted through the second transmission wavelength selection region 4b is g
The wavelength range of the line, the h line and the i line is included. Therefore,
Second transmission wavelength selection region 4b in the photoresist 61
In the region 62 corresponding to (3), the photolysis was completely carried out, and all could be solubilized. As a result, it could be completely dissolved by the developing solution and the resist hole 64 could be formed. On the other hand, the 1st transmitted light 9 which permeate | transmitted the 1st transmission wavelength selection area | region 4a is a light of i-line and a short wavelength area of 300 nm or less. Therefore, in the region 63 corresponding to the first transmission wavelength selection region 4a, only the photo-sensitive group exhibiting the light absorption property for the i-line and the deep UV in the photosensitive resin forming the photoresist 61 is photo-decomposed. . Therefore, the proportion of the photodecomposed polymer is smaller than that in the region 62, and the solubility in the developing solution is small. As a result, the photosensitive resin could be left in the region 63 without being completely dissolved. That is, the resist step 65 could be formed.

As described above, in the pattern forming method using the multi-layer resist, the sensitivity does not change due to the length of the developing time, so that it is easy to handle and the developing process can be easily performed. Further, by performing pattern formation by combining the photomask according to the first embodiment and the multilayer resist, it is possible to make the surface uniform and further improve the exposure contrast to perform patterning having a resist step. It was Moreover, by improving the exposure contrast, the cross-sectional shape of the pattern can be made more rectangular.

In the present embodiment, the case has been described in which a photoresist made of two kinds of photosensitive resins having mutually different wavelength regions showing sensitivity is used. But,
The present invention is not limited to this. That is, when it is desired to provide steps in multiple stages, for example, another photosensitive resin having sensitivity in a wavelength region different from the wavelength region in which the two types of photosensitive resins have sensitivity may be mixed and used. . The mixing ratio of each photosensitive resin needs to be appropriately set according to various exposure conditions such as the wavelength range of light emitted from the light source of the exposure device and the size of the step.

(Embodiment 7) Embodiment 7 relates to a semiconductor element and a method for manufacturing the same. However,
In the following, a thin film transistor will be described as an example, but the present invention is not limited to this, and is applicable to a thin film diode.

When a semiconductor element is formed by using a conventional gradation mask or the like, there is a problem that element characteristics vary among semiconductor elements. As a result of studying this point, the inventors of the present application have newly found that the fact that the layer thickness of the portion corresponding to the channel region of the semiconductor layer is nonuniform between the semiconductor elements has a new influence.

For example, when the gradation mask is used, the surface of the portion corresponding to the channel region of the semiconductor layer becomes non-uniform due to the following reason. That is, the gradation mask controls the light transmittance by controlling the layer thickness of the chromium film to perform patterning with steps. However, the relationship between the layer thickness of the chrome film and the light transmittance changes significantly even if the layer thickness is slightly changed.Therefore, strictly control the light transmittance to obtain the desired transmittance. Is difficult to do. As a result, the amount of transmitted light varies, and the layer thickness varies between elements, such as the difference in layer thickness from the semiconductor layers in other semiconductor elements.

Further, in the case of a mask provided with a mask pattern below the resolution limit of the exposure apparatus, it is difficult to uniformly form a mask pattern below the resolution limit, so that the amount of transmitted light also varies, This causes variations in layer thickness between semiconductor elements.

With respect to such a problem, the semiconductor device manufacturing method according to the seventh embodiment described below can suppress variations in device characteristics. FIG. 10 is a schematic sectional view schematically showing a method for manufacturing a semiconductor element.

First, a gate electrode 71 patterned into a predetermined shape is formed on the substrate 6 by a conventional method, and the gate insulating film 7 made of silicon nitride SiN _x is formed.
2, a semiconductor layer 73 made of n ⁺ Si / a-Si, and a source / drain metal layer 74 mainly made of aluminum were continuously formed in this order. Subsequently, OFPR5000 (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied on the source / drain metal layer 74 to form a photoresist 75.
Was formed (see FIG. 10A).

Next, a photomask 70 for patterning the photoresist 75 was prepared. That is, after forming a single-layer chromium film on the glass substrate 2 by the same method as described in the first embodiment, the single-layer chromium film was patterned to form the light shielding portion 76.

Then, similarly to the first embodiment,
After forming the ITO film, the ITO film was patterned to form the first transmission wavelength selection region 77. The second transmission wavelength selection area 78 is composed of a space portion excluding the light shielding portion 76 and the first transmission wavelength selection area 77. As a result, a photomask 70 having a mask pattern corresponding to the element shape to be formed was produced on the glass substrate 2.

Next, as shown in FIG. 13A, exposure was performed through a photomask 70 in order to pattern the photoresist 75. As the exposure device, the same device as described in the first embodiment was used, and the exposure amount of the exposure light was 100 mJ / cm ² .

Subsequently, development processing was performed by the Pudle method. That is, the developing solution was discharged onto the substrate 6 rotating at a low speed, and then the substrate 6 was left stationary. As a developer,
An aqueous solution containing 2.38 wt% of TMAH (tetramethylammonium hydroxide) was used. In addition, the time for which the developing solution was allowed to stand still on the substrate 6 was set to 120 seconds. As a result, a part of the photoresist 75 remains in the region corresponding to the light shielding portion 76, and a resist mask 79 having a pattern shape corresponding to the element shape can be formed (FIG. 1).
0 (b)). Further, in the region corresponding to the first transmission wavelength selection region 77, only the upper layer portion of the photoresist 75 was removed and a part thereof remained, and the recess 80 was formed. further,
The photoresist 75 was completely removed in the region corresponding to the second transmission wavelength selection region 78, and the source / drain metal layer 74 was exposed.

Next, dry etching was performed using the resist mask 79 as a mask to expose the gate insulating film 72 except for the region covered with the resist mask 79 (FIG. 1).
0 (c)). At this time, the recess 80 in the resist mask 79 and the source / drain metal layer 74 were completely removed, and further a part of the semiconductor layer 73 was also removed. As a result,
Portion 81 corresponding to the channel region in the semiconductor layer 73
Could be exposed on the surface.

Then, a resist mask 7 is formed by using a stripping solution.
9 was peeled off, whereby a channel-etch type semiconductor element 82 could be obtained (FIG. 10D).

As described above, in the method of manufacturing a semiconductor device according to the seventh embodiment, compared with the case where the conventional ordinary mask is used, the channel etch type is performed by one exposure and development process. The semiconductor element can be obtained, and the productivity can be improved more than ever before. In addition, in the present embodiment, by using the ITO film, light in a specific wavelength region is blocked or attenuated to adjust the irradiation energy of light and form a stepped pattern. Therefore, it is possible to form an element without causing variations like a gradation mask. As a result, it is also possible to suppress variations in element characteristics among semiconductor elements and suppress a decrease in yield to manufacture semiconductor elements.

An active matrix substrate having a plurality of semiconductor elements formed on a glass substrate was prepared, and a liquid crystal panel equipped with this active matrix substrate was prepared. Subsequently, an external circuit for driving a semiconductor element was attached to this liquid crystal panel to manufacture a liquid crystal display device. When an image was displayed on this liquid crystal display device, it was confirmed that the color reproducibility did not become non-uniform in the plane and that good display characteristics were exhibited.

In this embodiment, the example using the photomask according to the first embodiment has been described, but the present invention is not limited to this. That is, it can be similarly implemented by combining the various photomasks according to the second and third embodiments with the photoresist according to the fourth to seventh embodiments.

(Embodiment 8) Embodiment 8 relates to a reflector and a method for manufacturing the same, a liquid crystal display device including the reflector, and a method for manufacturing the same. Figure 11
[Fig. 4] is a schematic cross-sectional view for explaining a method for manufacturing a reflector. FIG. 12 is a plan view showing a photomask used in this embodiment.

First, as shown in FIG. 11A, the substrate 9
PC403 (trade name, manufactured by JSR Co., Ltd.) was applied on the surface of No. 5 to form a photosensitive resin layer 96 (layer thickness: 1.5 μm).
In addition, on the substrate 95, for example, a TFT or the like (not shown)
Also, source / drain metal lines 97 are formed.

Next, the photosensitive resin layer 96 is exposed using the photomask 91. The photomask 91 is basically a mask structure that exhibits the same function as the photomask described in the first embodiment except that the mask pattern is different. Specifically, FIG. 1A and FIG.
As shown in FIG. 2, the light shielding portion 92 and the first
Transmission wavelength selection area 93a and second transmission wavelength selection area 9
And a transmitting portion 93 having 3b.

The light shielding portion 92 is made of a single layer chromium film. The first transmission wavelength selection area 93a is an i-line and deep UV.
It is made of ITO _x for transmitting light and has a circular shape with a diameter of 7 μm. The first transmission wavelength selection area 93a reflects light.
In order to scatter, the surface layer portion of the photosensitive resin layer is provided to have an uneven shape. In addition, the second transmission wavelength selection region 9
3b is a rectangular shape having a space for transmitting g-line, h-line and i-line and having a length (l) of 12 μm and a width (w) of 10 μm. The second transmission wavelength selection region 93b is provided to form a contact hole for electrically connecting the source / drain metal line 97 and the metal layer provided on the photosensitive resin layer 96.

Through the photomask 91 having such a structure, the photosensitive resin layer 96 was exposed by the same exposure apparatus as used in the first embodiment. The exposure amount is 150
It was set to mJ / cm ² .

Next, the developing solution was applied to the substrate 95 by the Pudddle method by allowing the developing solution to stand still for a predetermined period of time and allowing it to stand. As the developing solution, an aqueous solution containing 0.4 wt% of TMAH was used. As a result, on the source / drain metal line 97,
A contact hole 98 was formed to expose at least a part of the source / drain metal line 97 (FIG. 11B). Further, a plurality of uneven portions 99 ... Can be formed in the other regions.

Subsequently, the substrate 95 is placed on the hot plate 1
Heated at 50 ° C. for 5 minutes. As a result, the corners of the uneven portion 99 were melted by heat to form a curved surface, and as shown in FIG. 11C, it was possible to obtain the photosensitive resin layer 101 having a smooth and continuous surface layer portion. Further, by forming a metal film (not shown) made of aluminum (Al) on this photosensitive resin layer 101, the reflection plate according to the eighth embodiment was obtained. The metal film can be formed of a metal having a high reflectance such as a silver-copper-palladium alloy.

When the reflection characteristics of the thus obtained reflector are examined, it is found that the variation is reduced and the light is reflected uniformly as compared with the reflector manufactured by using a conventional gradation mask or the like. Was confirmed.

Further, the reflection plate and a counter substrate facing the reflection plate were bonded to each other to prepare an empty cell, and liquid crystal was injected into the empty cell to prepare a liquid crystal panel. Subsequently, an external circuit or the like was attached to the liquid crystal panel to manufacture a liquid crystal display device. When an image was displayed on this liquid crystal display device, it was confirmed that the color reproducibility did not become non-uniform in the plane and that the display quality was good.

As described above, in the manufacturing method according to the present embodiment, the contact hole and the unevenness of the surface layer portion of the photosensitive resin layer can be collectively formed, so that the number of photolithography steps can be reduced. It That is, in the case of a normal photomask that has been conventionally used, one step was required to form a contact hole, two steps were required to form an uneven portion, and a total of three steps of photolithography steps were required. According to the manufacturing method of the above embodiment, the photolithography process only needs to be performed once. Therefore, the production cost can be suppressed by improving the takt time. Here, unlike the present embodiment, the reason why the concave portion reaching the substrate 95 is not formed is that when such a hole is formed, the concave-convex portion becomes a tapered sharp shape and the reflection characteristic deteriorates. Is.

In order to realize a high-brightness reflection characteristic,
It is sufficient to make the surface uneven and reflect / scatter incident light. However, if the unevenness of the surface is not uniform, the in-plane reflection characteristics will fluctuate, which is a major cause of yield reduction. .

Such a variation in the reflection characteristics has occurred especially when the surface layer portion of the photosensitive resin layer is made uneven by using a conventional gradation mask or the like. However, the manufacturing method according to the eighth embodiment. In this case, it is possible to form an uneven shape having a uniform size and shape. As a result, it is possible to suppress variations in the reflection characteristics within the surface and improve the yield.

Although the example using the photomask according to the first embodiment has been described in the present embodiment, the present invention is not limited to this. That is, various photomasks according to the first to third embodiments,
It can be similarly implemented by combining with the photoresist according to the fourth to seventh embodiments.

(Ninth Embodiment) The ninth embodiment relates to a semi-transmissive reflection plate and a method for manufacturing the same, a liquid crystal display device having a semi-transmission reflection plate, and a method for manufacturing the same. FIG. 13 is a schematic cross-sectional view for explaining a method of manufacturing a semi-transmissive reflection plate. FIG. 14 is a plan view showing a photomask used in this embodiment.

First, as shown in FIG. 13A, a PC 403 (trade name, JSR) is mounted on a transparent substrate 114.
Co., Ltd.) was applied to form a photosensitive resin layer 115 (layer thickness: 3.5 μm). Note that, for example, TFTs (not shown) are formed on the substrate 114.

Next, the photosensitive resin layer 115 was exposed using the photomask 111. Photo mask 11
1 has a mask configuration that basically exhibits the same function except that the photomask described in the first embodiment is different from the mask pattern. Specifically, as shown in FIG. 14A and FIG. 14, the light shielding portion 112 is formed on the glass substrate 2.
And a transmission part 113 having a first transmission wavelength selection region 113a and a second transmission wavelength selection region 113b.

The light shielding portion 112 is made of a single layer chromium film.
The first transmission wavelength selection region 113a is made of an ITO _x film that transmits i-line and deep UV, and has a circular shape with a diameter of 7 μm. The first transmission wavelength selection area 113a is provided to make the surface layer portion of the photosensitive resin layer uneven so as to reflect / scatter light. Further, the second transmission wavelength selection region 113b is composed of a space portion that transmits g-line, h-line and i-line, and is a square of 20 μm × 20 μm. The second transmission wavelength selection area 113b is provided to form a transmission hole for transmitting a part of light in the reflection plate.

The photomask 111 having such a configuration
Through the above, the photosensitive resin layer 115 was exposed with the same exposure apparatus as that used in the first embodiment. 2 exposure
It was set to 50 mJ / cm ² .

Next, the substrate 114 is formed by the Puddle method.
The developing solution was left standing and allowed to stand for a predetermined time for development processing.
As the developing solution, an aqueous solution containing 0.4 wt% of TMAH was used. As a result, a hole 117 that exposes a part of the substrate 114 could be formed in a region corresponding to the second transmission wavelength selection region 113b (FIG. 13B). Further, a plurality of recesses 118 ... Having a predetermined depth could be formed in the other regions.

Subsequently, the substrate 114 was heated on a hot plate at 150 ° C. for 5 minutes. As a result, the concave portion ... 118
A photosensitive resin layer 1 including a transparent hole 120 that allows light to pass therethrough by melting heat at the corners of the region where the
19 could be obtained (FIG. 13 (c)). The layer thickness difference between the transparent hole 120 and the bottom of the uneven portion 121 is about 1.7 μm.
Met. Further, by forming a metal film (not shown) made of aluminum (Al) on this photosensitive resin layer 119, a semi-transmissive reflection plate according to the ninth embodiment was obtained. The metal film can be formed of a metal having a high reflectance such as a silver-copper-palladium alloy.

Further, this semi-transmissive reflection plate and the counter substrate facing it were bonded to each other to prepare an empty cell, and liquid crystal was injected into this empty cell to prepare a liquid crystal panel. Subsequently, an external circuit or the like was attached to the liquid crystal panel to manufacture a liquid crystal display device. When an image was displayed on this liquid crystal display device, it was confirmed that the color reproducibility did not become non-uniform in the plane and that the display quality was good.

As described above, in the manufacturing method according to the ninth embodiment, the transmission holes and the unevenness of the surface layer portion of the photosensitive resin layer are collectively formed, so that the number of photolithography steps is reduced. be able to. That is, in the case of a conventional photomask that has been used conventionally, one step was required for forming the contact hole, two steps were required for forming the concavo-convex portion, and a total of three steps of photolithography steps were required. With the manufacturing method according to this mode, the photolithography process only needs to be performed once. Therefore, the production cost can be suppressed by improving the takt time.

In order to realize a high-brightness reflection characteristic,
It is sufficient to make the surface uneven and reflect the incident light as scattered light, but if the sizes are uneven, uneven reflection characteristics occur within the plane, which is a major cause of yield reduction. It was.

Such variations in the reflection characteristics have occurred when the surface layer portion of the photosensitive resin layer is made uneven by using a conventional gradation mask or the like, but it is the manufacturing method according to the present embodiment. By doing so, it is possible to form an uneven shape having a uniform size. As a result, it is possible to suppress variations in the reflection characteristics within the surface and improve the yield.

In the present embodiment, the example using the photomask according to the first embodiment has been described, but the present invention is not limited to this. That is, various photomasks according to the first to third embodiments,
It can be similarly implemented by combining with the photoresist according to the fourth to seventh embodiments.

(Other Matters) In each of the above embodiments, as an example of pattern formation in the transfer process,
Although the photomask and the photolithography method using the photomask have been described, the present invention is not limited thereto. That is, it is also applicable to photolithography using visible light, X-ray lithography, electron beam lithography, and ion beam lithography depending on the transmission medium that transfers the mask pattern information onto the substrate.

[0170]

The present invention is carried out in the form described above, and has the following effects. That is, according to the mask of the present invention, the pattern precision in cross-sectional view is extremely good, and the exposure contrast uniformity can be made excellent. Therefore, with the mask according to the present invention, an element having a complicated three-dimensional structure can be easily formed,
It is possible to provide a manufacturing mask that is compatible with the miniaturization of elements.

Further, according to the pattern forming method of the present invention, it is possible to form a pattern having a step on the photosensitive resin layer by one exposure, and the number of manufacturing steps can be reduced.
In addition, since the surface of each step can be made uniform and patterning with high pattern precision can be performed, the yield can be improved.

Further, according to the lithographic method of the present invention, a resist mask having an extremely high degree of precision can be formed, so that it is possible to perform patterning on an arbitrary thin film with high precision. As a result, even elements with a complicated three-dimensional structure,
It can be formed with improved yield.

[Brief description of drawings]

FIG. 1 is a schematic sectional view for explaining a photolithography process according to a first embodiment of the present invention, in which FIG.
Shows a state where the photoresist is exposed through a photomask, and FIG. 7B shows a state of the photoresist after development.

FIG. 2 is an explanatory diagram for explaining the method of manufacturing the photomask according to the first embodiment.

FIG. 3 is a schematic sectional view for explaining a photolithography process according to the second embodiment of the present invention, in which FIG.
Shows a state where the photoresist is exposed through a photomask, and FIG. 7B shows a state of the photoresist after development.

FIG. 4 is a graph showing a relationship between a film thickness D of a thin film and a light transmittance T (%) in the second embodiment.

FIG. 5 is an explanatory diagram for explaining a pattern shape of a photoresist when a photolithography process is performed using a photomask for comparison with the photomask according to the third embodiment of the present invention, 11A is a cross-sectional view showing the structure of the photomask, FIG. 11B is a graph showing the relationship between the amount of light transmitted through the photomask and the exposure position, and FIG. 8A is a cross-sectional view showing a photoresist after being exposed using the photomask and further developed. FIG.

FIG. 6 is an explanatory diagram for explaining a pattern shape of a photoresist when a photolithography process is performed using the photomask according to the third embodiment of the present invention,
11A is a cross-sectional view showing the structure of the photomask, FIG. 11B is a graph showing the relationship between the amount of light transmitted through the photomask and the exposure position, and FIG. 8A is a cross-sectional view showing a photoresist after being exposed using the photomask and further developed. FIG.

FIG. 7 is a plan view showing a main part of a photomask according to a third embodiment of the present invention.

FIG. 8 is a schematic sectional view for explaining a photolithography process according to the fourth embodiment of the present invention, in which FIG.
Shows a state where the photoresist is exposed through a photomask, and FIG. 7B shows a state of the photoresist after development.

FIG. 9 is a schematic sectional view for explaining a photolithography step according to the sixth embodiment of the present invention, in which FIG.
Shows a state where the photoresist is exposed through a photomask, and FIG. 7B shows a state of the photoresist after development.

FIG. 10 is a schematic cross sectional view schematically showing a method for manufacturing the semiconductor element according to the seventh embodiment of the present invention.

FIG. 11 is a schematic cross sectional view for explaining the manufacturing method for the reflector according to the eighth embodiment of the present invention.

FIG. 12 is a plan view showing a photomask used in the method of manufacturing a reflector according to the eighth embodiment.

FIG. 13 is a schematic cross sectional view for illustrating the method for manufacturing the semi-transmissive reflector according to the ninth embodiment of the present invention.

FIG. 14 is a plan view showing a photomask used in the method of manufacturing a semi-transmissive reflector according to the ninth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Photomask (mask) 2 Glass substrate (support) 3 Light-shielding part 4 Transmission part 4a First transmission wavelength selection region 4a Second transmission wavelength selection region 6, 95, 114 Substrate 7, 23, 43, 61, 75 Photoresist 8 exposure light 9 first transmitted light 10 second transmitted light 11, 13 thin film regions 12, 14 removal region 21 chrome film 22 ITO film 31 photomask (mask) 32 transmissive portion 32a first transmissivity control region 32b second transmissivity Control region 41 Photomask (mask) 42 Transmissive part 42a First transmissive region 42b Second transmissive region 44, 57, 64 Resist hole 45, 56, 65 Resist step 46 Pinhole 47 Photomask (mask) 48 Auxiliary light shielding part 51 Surface layer 52 Lower Layer 53 Exposure Light 54 First Transmitted Light 55 Second Transmitted Light 70 Photomask (Mask) 71 Gate Electrode 72 No Gate Film 73 Semiconductor layers 74, 97 Source / drain metal layer 76 Light-shielding portion 77 First transmission wavelength selection region 78 Second transmission wavelength selection region 79 Resist mask 80 Recess 82 Semiconductor element 91 Photomask (mask) 92 Light-shielding portion 93 Transmission portion 93a First transmission wavelength selection region 93b Second transmission wavelength selection region 96, 101, 115, 119 Photosensitive resin layer 98 Contact hole 99 Recess 111 Photomask (mask) 112 Light-shielding portion 113 Transmission portion 113a First transmission wavelength selection region 113b 2 Transmission wavelength selection area 117 Hole 118 Recessed portion 120 Transmission hole 121 Concavo-convex portion P _{1 to} P ₃ peak

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/30 573 F term (reference) 2H025 AA00 AB14 AB16 AC01 AD01 DA13 EA08 2H095 BA01 BB35 BC05 5F046 AA25 CB17 LA18 LA19 NA19

Claims (31)

[Claims] 1. A mask used for exposing at least one photosensitive resin layer laminated on a substrate to form a latent image on the photosensitive resin layer, wherein the mask is transparent. And a opaque light-shielding portion and a transmissive portion provided on the support, the transmissive portion having a plurality of transmission wavelength selection regions in which wavelength regions of light to be transmitted are different from each other. A mask characterized by that. 2. The mask according to claim 1, wherein at least one of the plurality of transmission wavelength selection regions is made of a material different from that of the light shielding portion. 3. A mask used for exposing a photosensitive resin layer provided on a substrate to form a latent image on the photosensitive resin layer, wherein the mask is a transparent support. And an opaque light-shielding portion and a light-transmitting portion provided on the support, wherein the light-transmitting portion substantially transmits light including a wavelength region in which the photosensitive resin layer has sensitivity. A mask having a plurality of transmittance control regions that are present and have different light transmittances. 4. The mask according to claim 3, wherein at least one of the plurality of transmittance control regions is made of a material different from that of the light shielding portion, and a rate of change in transmittance with respect to thickness is A mask characterized by being made of a material smaller than the light-shielding portion. 5. The mask according to claim 4, wherein the plurality of transmittance control regions have different thicknesses so that the transmittance of light has a predetermined value. . 6. The mask according to any one of claims 3 to 5, wherein the transmissive portion forms the metal film when the light shielding portion is made of a predetermined metal film. A mask comprising a metal oxide, wherein the layer thickness of the transmissive portion is in the range of ½ or more and 4/5 or less of the layer thickness of the light shielding portion. 7. The mask according to claim 6, wherein the metal film is made of chromium. 8. The mask according to claim 1, wherein the transmission part includes an inorganic oxide. 9. The mask according to claim 8, wherein the inorganic oxide is indium tin oxide, indium oxide,
At least one selected from the group consisting of tin oxide, silicon oxide, chromium oxide, titanium oxide, aluminum oxide, yttrium oxide, and hafnium oxide.
A mask characterized by being a seed oxide. 10. The mask according to claim 8, wherein the inorganic oxide is a lower oxide. 11. The mask according to claim 1, wherein the transmission part includes a halide of an alkaline earth metal. 12. The mask according to claim 1, wherein an auxiliary light shielding portion is provided between the plurality of transmission wavelength selection regions. mask. 13. A photosensitive resin layer is formed on a substrate, and the photosensitive resin layer is exposed to light through the mask according to any one of claims 1 to 12. A pattern forming method comprising forming a latent image of a shape and then developing the exposed photosensitive resin layer to form a stepped pattern on the photosensitive resin layer. 14. A pattern forming method for performing stepped patterning on a plurality of photosensitive resin layers laminated on a substrate, comprising: an opaque light-shielding portion and a light-transmitting portion for transmitting light on a transparent support. A mask provided with a transmission part having a plurality of transmission wavelength selection regions having different wavelength regions from each other is prepared, and a plurality of the photosensitive resin layers having sensitivity to different wavelength regions are laminated on the substrate. After forming a multi-layered structure by exposing the plurality of photosensitive resin layers that are the multi-layered structure through the mask, a latent image from the surface layer or from the surface layer to a predetermined layer for each region of the multi-layered structure. And by developing the multilayer structure after exposure,
A pattern forming method, which comprises forming a pattern having at least one step. 15. The pattern forming method according to claim 14, wherein at least one of the plurality of photosensitive resin layers is formed.
A pattern forming method, which comprises forming a dry film resist layer on the layer. 16. A pattern forming method for performing stepwise patterning on a photosensitive resin layer provided on a substrate, comprising: an opaque light-shielding portion and a wavelength region of light to be transmitted on a transparent support. A mask provided with a transmission part having a plurality of transmission wavelength selection regions different from each other is prepared, and the photosensitivity including at least two types of photosensitive resins having sensitivity to wavelength regions different from each other on the substrate. After forming the resin layer, the photosensitive resin layer is exposed through the mask to form a latent image at a predetermined depth position in each region of the photosensitive resin layer, and the exposed photosensitive layer is further exposed. A pattern forming method, which comprises forming a stepped pattern by developing a functional resin layer. 17. A lithographic method for patterning an arbitrary thin film provided on a substrate into a predetermined shape, wherein a resist layer is formed on the substrate via the thin film, and the resist layer is formed. By exposing the resist layer through the mask described in 1, a latent image having a predetermined shape is formed, and then developing the exposed resist layer to form a pattern having a resist step in the resist layer. And a step of etching the thin film to peel off the resist layer after development. 18. A lithographic method for patterning an arbitrary thin film formed on a substrate into a predetermined shape, wherein an opaque light-shielding portion and a wavelength range of light to be transmitted are mutually provided on a transparent support. A mask provided with a transmission part having a plurality of different transmission wavelength selection regions is prepared, and a plurality of resist layers having sensitivity to different wavelength regions are laminated on the substrate to form a multilayer structure. After that, by exposing the plurality of resist layers that are the multilayer structure through the mask, a latent image is formed on the surface layer or from the surface layer to a predetermined layer for each region of the multilayer structure, and after the exposure, The multilayer structure is developed to form at least one stepped pattern, and the thin film is etched to form a stepped pattern on the thin film. A lithographic method, characterized in that a distant layer is peeled off. 19. The lithography method according to claim 18, wherein a dry film resist layer is formed on at least one of the plurality of resist layers. 20. A lithographic method for patterning an arbitrary thin film provided on a substrate into a predetermined shape, wherein an opaque light-shielding portion and a wavelength region of light to be transmitted are mutually provided on a transparent support. A mask provided with a transmission part having a plurality of different transmission wavelength selection regions, and a resist layer containing at least two types of photosensitive resins showing sensitivity to mutually different wavelength regions is formed on the substrate. After that, by exposing the resist layer through the mask, a latent image is formed to a predetermined depth position for each region of the resist layer, and the exposed resist layer is developed to obtain at least 1 Forming a pattern with two resist steps, etching the thin film to form a step pattern on the thin film, and further peeling the resist layer A lithographic method characterized by: 21. The lithographic method according to claim 20, wherein the resist layer is a mixture of two or more kinds of photosensitive resins having sensitivity to mutually different wavelength regions at a predetermined mixing ratio. A lithographic method comprising: 22. A method of manufacturing a semiconductor device, which comprises forming a semiconductor device on the substrate using the lithography method according to claim 17. 23. A semiconductor device manufactured by the method for manufacturing a semiconductor device according to claim 22, wherein a part of the semiconductor device has a stepwise cross-sectional shape. Semiconductor device that does. 24. The semiconductor element according to claim 23, wherein the stepwise portion in the cross-sectional shape is
A semiconductor device comprising a thin film having two or more layers. 25. The semiconductor element according to claim 23 or 24, which is a thin film transistor or a thin film diode. 26. A liquid crystal panel comprising the semiconductor element according to claim 23. 27. A plurality of irregularities are formed on the substrate by forming a stepped pattern on the photosensitive resin layer by using the pattern forming method according to any one of claims 13 to 17. And a light reflection film is formed on the substrate on which the uneven portion is provided. 28. A reflection plate manufactured by the method of manufacturing a reflection plate according to claim 27. 29. A semi-transmissive reflection plate manufactured by the method for manufacturing a reflection plate according to claim 27, wherein the substrate has transparency, and the light is reflected by the light reflection film. A reflection plate, which is provided with a region and a region where the light reflection film is not provided and which transmits light. 30. A liquid crystal panel comprising the reflection plate according to claim 28 or 29. 31. A liquid crystal display device, comprising: the liquid crystal panel according to claim 26 or 30; and a drive circuit for driving the liquid crystal panel.