JP2004221137A - Resist pattern forming method and manufacturing method of semiconductor device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resist pattern forming method, along with a manufacturing method of a semiconductor device using the same, capable of suppressing the reduction in line thickness of the resist pattern which is caused by electron ray irradiation by SEM to a value range that imposes no problem in a manufacturing process. <P>SOLUTION: A silicon dioxide film 2, a reflection preventing film 3, and a resist film 4 are formed on a semiconductor substrate 1. After the resist film 4 is irradiated with an exposure light 6 through a prescribed mask 5, a heating process and a development process are performed. By setting a side wall angle θ of the resist pattern which has been formed to 88°≤θ≤89°, the reduction amount of line thickness of the resist pattern 7 can be minimized. Thus, a fine resist pattern is formed under good control for dimension. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for forming a resist pattern and a method for manufacturing a semiconductor device using the same.
[0002]
[Prior art]
In recent years, as the degree of integration of semiconductor devices has increased, the dimensions of individual elements have been miniaturized, and the widths of wirings, gates, etc. constituting each element have also been miniaturized.
[0003]
The photolithography technology that supports this miniaturization includes a process of applying a resist composition to the surface of a substrate to be processed to form a resist film, and irradiating light to expose a predetermined resist pattern to form a resist pattern latent image. Forming, a heat treatment if necessary, a step of developing this to form a desired fine pattern, and a step of performing processing such as etching on the substrate to be processed using the fine pattern as a mask. included.
[0004]
As one of means for miniaturizing a pattern, shortening the wavelength of exposure light used for forming the resist pattern latent image has been promoted.
[0005]
Conventionally, in the manufacture of a DRAM (Dynamic Random Access Memory) having a degree of integration of, for example, up to 64 Mbits, an i-line (wavelength: 365 nm) of a high-pressure mercury lamp has been used as a light source. In recent years, a technology using a KrF (krypton fluoride) excimer laser (wavelength: 248 nm) as an exposure light source has been put to practical use in a mass production process of a 256 megabit DRAM. For the manufacture of a DRAM having a degree of integration of 1 gigabit or more, practical use of an ArF (argon fluoride) excimer laser (wavelength: 193 nm) is being studied. Furthermore, as a technique for realizing a fine pattern corresponding to a design rule of 100 nm or less, use of an F ₂ (fluorine) excimer laser (wavelength: 157 nm) having a shorter wavelength as an exposure light source has been considered.
[0006]
On the other hand, electron beam lithography technology is being developed as a higher resolution exposure technology. Since the electron beam lithography technology has an essentially excellent resolution, it is also used in the production of some ASICs (Application Specific Integrated Circuits) in addition to DRAMs.
[0007]
In a resist used for such a photolithography technique or an electron beam lithography technique, a resist material is changed according to an exposure light source. For example, an acrylic polymer is mainly used for a resist used in an exposure apparatus using an ArF excimer laser as a light source. Further, the resist used for the exposure apparatus as a light source an F ₂ excimer laser, primarily the fluorine-containing polymer is used.
[0008]
[Problems to be solved by the invention]
By the way, in order to confirm that the resist pattern formed by the above process is formed in a desired shape, observation is performed by a scanning electron microscope (hereinafter, referred to as SEM). For example, line width measurement or the like for inspecting whether or not the resist pattern is finished to the specified size is performed using the SEM.
[0009]
The SEM is for irradiating the surface of a sample with an electron beam and detecting secondary electrons jumping out of the sample while scanning the irradiation position. However, KrF excimer laser, ArF resist material used in the exposure apparatus according to an excimer laser or F ₂ excimer laser or the like source is less resistance to electron beam irradiation, may cause decomposition reaction or a crosslinking reaction by electron beam irradiation Many. Therefore, for example, while measuring the line width of the resist pattern using the SEM, there is a problem that the line width decreases.
[0010]
Since the dimension of the resist pattern is reduced in the observation process by the SEM, there has been a problem that accurate dimension measurement is difficult and the dimension controllability of the resist pattern is significantly reduced. For this reason, there has been a problem that the yield in the semiconductor manufacturing process is reduced and the reliability of the semiconductor device is reduced. In addition, such a problem of the line width phenomenon has been a problem particularly in a semiconductor device having a design rule of 150 nm or less.
[0011]
The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a method of forming a resist pattern capable of reducing the line width reduction of a resist pattern caused by electron beam irradiation by a SEM within a range having no problem in a manufacturing process, and manufacturing a semiconductor device using the same. It is to provide a method.
[0012]
Another object of the present invention, KrF excimer laser, even and an ArF excimer laser or F ₂ excimer laser a fine resist corresponding to an exposure apparatus whose light source, capable of forming a pattern with good dimensional controllability An object of the present invention is to provide a method for forming a resist pattern and a method for manufacturing a semiconductor device using the same.
[0013]
Other objects and advantages of the present invention will become apparent from the following description.
[0014]
[Means for Solving the Problems]
The present invention includes a step of forming a resist film on a substrate to be processed, a step of forming a resist pattern latent image by irradiating the resist film with exposure light through a predetermined mask, and a heat treatment on the resist film. Forming a resist pattern by performing a developing process on the resist film, wherein the side wall angle of the resist pattern is 88 to 89 degrees. It is.
[0015]
In the step of performing the heat treatment, the size of the side wall angle can be controlled by adjusting the heating time and / or the heating temperature.
[0016]
The substrate to be processed can have an antireflection film, and a resist film can be formed on the antireflection film. The size of the side wall angle can be controlled by adjusting the thickness of the antireflection film.
[0017]
The line width of the resist pattern can be set to 150 nm or less.
[0018]
The exposure light may be KrF excimer laser light having a wavelength of 248 nm.
[0019]
The exposure light may be ArF excimer laser light having a wavelength of 193 nm.
[0020]
Further, exposure light can be a _{F 2} excimer laser beam having a wavelength of 157 nm.
[0021]
Further, the exposure light can be an electron beam.
[0022]
The present invention also relates to a method for manufacturing a semiconductor device using the above-described method for forming a resist pattern using a substrate to be processed as a semiconductor substrate.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
A method for forming a resist pattern according to the present embodiment and a method for manufacturing a semiconductor device using the same will be described with reference to FIGS.
[0024]
First, a semiconductor substrate is prepared as a substrate to be processed. For example, as shown in FIG. 1, a silicon dioxide (SiO ₂ ) film 2 is formed on a semiconductor substrate 1.
[0025]
As the semiconductor substrate, for example, a silicon substrate can be used. An element isolation region, a diffusion layer serving as a source or a drain, or the like may be formed in the semiconductor substrate.
[0026]
The silicon dioxide film can be formed by, for example, a chemical vapor deposition method (hereinafter, referred to as CVD).
[0027]
The film formed on the semiconductor substrate is not limited to a silicon dioxide film. Other films may be formed as long as they are used in a semiconductor device manufacturing process and require patterning. For example, another insulating film such as a silicon nitride (Si ₃ N ₄ ) film may be formed, or a conductive film may be formed. Further, the film formed on the semiconductor substrate is not limited to a single-layer film, and may be a film in which two or more films are stacked. Further, these films may be formed on a semiconductor substrate on which a gate electrode and the like are formed.
[0028]
Next, as shown in FIG. 2, an antireflection film 3 is formed on the silicon dioxide film 2.
[0029]
The antireflection film 3 has a role of eliminating the reflection of the exposure light at the interface between the resist film and the antireflection film by absorbing the exposure light transmitted through the resist film when patterning the resist film formed in a later step. Fulfill. As the antireflection film, a film containing an organic substance as a main component can be used, and for example, can be formed by a spin coating method or the like. In the present invention, the anti-reflection film may not be provided.
[0030]
Next, a resist film 4 is formed on the antireflection film 3 as shown in FIG. For example, a resist film can be formed by a spin coating method or the like.
[0031]
The thickness of the resist film can be a predetermined thickness according to the manufacturing process of the semiconductor device. For example, in order to correspond to the exposure apparatus for KrF excimer laser, an ArF excimer laser or _{F 2} excimer laser as a light source may be a thickness in the range of 100 nm to 400 nm.
[0032]
As the resist, for example, a chemically amplified resist can be used. Specifically, a chemically amplified resist containing an alkali-insoluble polymer and an acid generator can be used. Examples of the alkali-insoluble polymer include those in which a protective group is introduced into a carboxyl group of a resin composed of an acrylic acid unit or the like, and those in which a protective group is introduced into a phenolic hydroxyl group of a resin composed of a compound unit having a phenol skeleton. Can be used. As the acid generator, a photoacid generator that generates an acid by light, an electron beam acid generator that generates an acid by an electron beam, and the like can be used. Examples of the photoacid generator include triphenylsulfonium triflate.
[0033]
Further, the resist used in the present invention may be a non-chemically amplified resist. Specifically, a resist containing a resin and a photosensitive agent can be used. For example, those containing a novolak resin and a quinone azide-based photosensitizer can be used.
[0034]
Next, as shown in FIG. 4, the resist film 4 is irradiated with exposure light 6 via a predetermined mask 5. As the exposure apparatus, for example, ultraviolet exposure device, an electron beam exposure apparatus, KrF excimer exposure apparatus, an ArF excimer exposure system or F ₂ excimer exposure apparatus can be used.
[0035]
KrF excimer laser light having a wavelength of 248 nm, in the case of using such an _{F 2} excimer laser light ArF excimer laser light or the wavelength 157nm wavelength 193nm as exposure light, the resist of chemical amplification type is preferably used.
[0036]
The exposure is performed for the purpose of forming a predetermined resist pattern latent image on the resist film 4. That is, by irradiating the resist film 4 with exposure light, a resist pattern latent image including an exposed portion 41 and an unexposed portion 42 is formed in the resist film 4 as shown in FIG. When a chemically amplified resist is used, an acid is generated from the acid generator contained in the resist film in the exposed portion 41. On the other hand, in the unexposed portion 42, the acid generator is not exposed, so that no acid is generated.
[0037]
Next, a heat treatment is performed on the exposed semiconductor substrate. When a chemically amplified resist is used, since the protective group is thermally decomposed by the catalytic action of an acid, it becomes alkali-soluble in the exposed area.
[0038]
After the heat treatment, the resist film is developed. The development can be performed, for example, by alkali development using an aqueous solution of tetramethylammonium hydroxide.
[0039]
For example, when a positive resist is used, an alkali-soluble polymer structure is formed in an exposed portion, while an alkali-insoluble polymer structure is formed in an unexposed portion. Therefore, by performing the alkali developing treatment, only the exposed portions are dissolved and removed in the developing solution, and as a result, a resist pattern 7 as shown in FIG. 5 is formed.
[0040]
Next, the developing solution attached to the semiconductor substrate and the resist dissolved in the developing solution are washed away with a rinsing solution. Specifically, the rinsing liquid can be washed away by discharging the rinsing liquid onto the semiconductor substrate in a shower state or a spray state. When an alkaline aqueous solution is used as the developing solution, pure water can be used as the rinsing solution, for example.
[0041]
After washing away the developing solution and the resist dissolved in the developing solution with the rinsing solution, the rinsing solution is removed by drying. For example, drying can be performed by rotating the semiconductor substrate at a high speed.
[0042]
The resist pattern after drying is observed using SEM. The SEM used in the present embodiment may be configured independently as an apparatus, or may be incorporated in an inspection apparatus such as a length measuring machine.
[0043]
FIG. 6 is an enlarged view of the resist pattern 8 after drying. As a result of intensive studies, the present inventor has found that when the angle θ between the side surface and the bottom surface of the resist pattern (hereinafter referred to as a side wall angle) θ satisfies 88 degrees ≦ θ ≦ 89 degrees, the electron at the time of SEM observation is obtained. It has been found that a reduction in line width due to line irradiation can be minimized. Here, the shape of the resist pattern 8 having the side wall angle θ in the range of 88 to 89 degrees shows a forward tapered shape as shown in FIG. When the side wall angle θ is larger than 90 degrees, the shape of the resist pattern 9 has an inverted tapered shape as shown in FIG.
[0044]
By setting the side wall angle of the resist pattern to 88 to 89 degrees, the incident angle of the electron beam during SEM observation can be made extremely shallow with respect to the side surface of the resist pattern. In this case, since the incident angle is not 0 (zero) degrees, the electron beam does not concentrate on a specific point such as the upper part of the resist pattern. That is, according to the present invention, it is possible to irradiate the entire resist pattern with an electron beam. This makes it possible to substantially reduce the intensity of the electron beam irradiated to the resist pattern, thereby minimizing a decomposition reaction, a crosslinking reaction, and the like of the resist caused by the electron beam irradiation. Therefore, a decrease in the line width due to electron beam irradiation at the time of SEM observation can be suppressed to a level that causes no problem in the manufacturing process.
[0045]
The magnitude of the side wall angle can be controlled by changing the conditions in the resist pattern forming step described with reference to FIGS. For example, it can be controlled by changing the time or temperature in the heat treatment after exposure.
[0046]
Specifically, the longer the heat treatment time, the larger the side wall angle, and the shorter the heat treatment time, the smaller the side wall angle. Also, the higher the heat treatment temperature, the larger the side wall angle, and the lower the heat treatment temperature, the smaller the side wall angle. For example, the heat treatment time is increased by about 30 seconds (60 seconds to 90 seconds, 90 seconds to 120 seconds, or the like), or the heat treatment temperature is increased by about 5 ° C. (115 ° C. to 120 ° C. or 130 ° C.). ° C to 135 ° C), and the side wall angle can be increased by about 5 to 10 degrees. Conversely, by shortening the heat treatment time by about 30 seconds (60 seconds to 30 seconds, 90 seconds to 60 seconds, etc.) or by lowering the heat treatment temperature by about 5 ° C. (115 ° C. to 110 ° C., 130 ° C. to 125 ° C.), and the side wall angle can be reduced by about 5 ° to 10 °.
[0047]
The size of the side wall angle can also be controlled by changing the thickness of the antireflection film formed below the resist film.
[0048]
Specifically, as the thickness of the antireflection film increases, the side wall angle decreases, and as the thickness of the antireflection film decreases, the side wall angle increases. For example, by setting the thickness of the antireflection film from 85 nm to 30 nm, the size of the side wall angle can be increased by about 5 degrees to 10 degrees.
[0049]
The specific fluctuation value of the side wall angle when the heat treatment time, the heating temperature, and the thickness of the antireflection film are changed also changes depending on the type of the resist used. Therefore, it is preferable to set appropriate conditions according to the resist.
[0050]
If the dimensions of the resist pattern in addition to the side wall angle are changed by changing the conditions in the resist pattern forming step, it is preferable to control the dimensions by adjusting the exposure amount. For example, in the case of a positive resist, the line width of the resist pattern decreases as the exposure amount increases, and the line width of the resist pattern increases as the exposure amount decreases.
[0051]
FIG. 7 shows an example of the relationship between the sidewall angle θ of the resist pattern and the reduction amount of the line width.
[0052]
The example of FIG. 7 shows a result of measuring a line width reduction amount caused by electron beam irradiation by SEM for a resist pattern having a different side wall angle θ formed using an ArF resist PAR-700 manufactured by Sumitomo Chemical Co., Ltd. . Here, the term "line width reduction amount" refers to a difference between a line width measured by irradiating an electron beam with a SEM in a short time of 0.5 seconds or less and a line width measured by irradiating an electron beam for 20 seconds. The line width when the electron beam irradiation time is 0.5 seconds or less can be approximated to the line width of the resist pattern before the electron beam irradiation.
[0053]
In the measurement in the example of FIG. 7, the energy of the electron beam is set to 500 V, the current value is set to 4 pA, and the threshold value is set to 50% by using a CD (Critical Dimension) -SEMS-9200 manufactured by Hitachi, Ltd.
[0054]
In FIG. 7, the horizontal axis indicates the sidewall angle θ of the resist pattern, and the vertical axis indicates the difference in line width due to the difference in the irradiation time of the electron beam, that is, the line width reduction amount. Therefore, as the value on the vertical axis increases, the amount of reduction in the line width due to electron beam irradiation increases.
[0055]
As shown in FIG. 7, the reduction amount of the line width changes depending on the magnitude of the side wall angle θ, and the reduction amount of the line width becomes substantially minimum when θ = 89 degrees. On the other hand, if the reduction in the line width is in the range of 2 nm or less, there is no problem in the manufacturing process. Therefore, it can be seen from FIG. 7 that when 88 degrees ≦ θ ≦ 89 degrees, the reduction amount of the line width is 2 nm or less.
[0056]
FIG. 8 shows another example of the relationship between the sidewall angle θ of the resist pattern and the reduction amount of the line width.
[0057]
In the example of FIG. 8, for different resist pattern sidewall angle θ made using the resist FX-1000P for F ₂ Clariant Corp., shows the results of measurement of the line narrowing amount generated by the electron beam irradiation by SEM . Here, the term "line width reduction amount" refers to a difference between a line width measured by irradiating an electron beam with a SEM in a short time of 0.5 seconds or less and a line width measured by irradiating an electron beam for 20 seconds. The line width when the electron beam irradiation time is 0.5 seconds or less can be approximated to the line width of the resist pattern before the electron beam irradiation.
[0058]
In the measurement in the example of FIG. 8, the energy of the electron beam is set to 500 V, the current value is set to 4 pA, and the threshold value is set to 50% using CD-SEM S-9200 manufactured by Hitachi, Ltd.
[0059]
In the example of FIG. 8 as well, the reduction amount of the line width changes depending on the magnitude of the side wall angle θ, and the reduction amount of the line width becomes substantially minimum when θ = 89 degrees. If the angle θ is 88 degrees to 89 degrees, the reduction amount of the line width can be set to 2 nm or less, and the value can be suppressed to a value that does not cause a problem in the manufacturing process.
[0060]
After a resist pattern is formed according to the method described in this embodiment, the silicon dioxide film can be processed into a desired pattern by etching the underlying silicon dioxide film using the resist pattern as a mask. In addition, by applying the etching process using the resist pattern as a mask to a method for manufacturing a semiconductor device, a semiconductor device having good element characteristics can be manufactured.
[0061]
In the present embodiment, a resist pattern formed on a semiconductor substrate has been described, but the present invention is not limited to this. The present invention can be applied to other uses as long as the purpose requires patterning of a base material using a resist pattern as a mask. For example, the base material may be a thin film formed on a glass substrate, or may be a thin film formed on a plastic substrate.
[0062]
According to the present embodiment, by setting the side wall angle θ of the resist pattern to 88 degrees to 89 degrees, damage to the resist received during electron beam irradiation is minimized, and the reduction of the line width is a problem in the manufacturing process. It is possible to suppress it to an extent that is not. Therefore, the manufacturing yield of the semiconductor device can be improved, and a highly reliable semiconductor device can be manufactured.
[0063]
Further, according to the present embodiment, even when the line width of the resist pattern is 150 nm or less, the amount of reduction in the line width due to electron beam irradiation can be made 2 nm or less. Therefore, KrF excimer laser, even and an ArF excimer laser or F ₂ excimer laser a fine resist corresponding to an exposure apparatus whose light source, it is possible to form a resist pattern with good dimensional controllability. In addition, it becomes possible to satisfactorily manufacture an advanced device having a small design rule.
[0064]
【Example】
Embodiment 1 FIG.
First, a silicon dioxide film was formed with a thickness of about 500 nm on a silicon substrate by a CVD method.
[0065]
Next, AR19 manufactured by Shipley was formed as an anti-reflection film on the silicon dioxide film. Specifically, the solution of AR19 was spin-coated on the silicon dioxide film by a spin coater, and then heat-treated at 215 ° C. for 90 seconds. The thickness of the obtained AR19 was about 85 nm.
[0066]
Subsequently, an ArF resist PAR-700 manufactured by Sumitomo Chemical Co., Ltd. was formed as a resist film on the antireflection film. Specifically, after the PAR-700 solution was spin-coated on the antireflection film by a spin coater, a heat treatment was performed at 110 ° C. for 60 seconds. The thickness of the obtained PAR-700 was about 250 nm.
[0067]
Next, using a Nikon exposure machine ArF excimer scanner S302A, an exposure light of 6.5 mJ / cm ² was applied to the resist film through a mask having a line and space pattern (line width 130 nm, space width 130 nm). Was irradiated. The numerical aperture (NA) of the exposure machine was 0.60, and σ (NA of light source / NA of lens) was 0.70.
[0068]
Next, the exposed silicon substrate was placed in a proximity-type closed oven and heat-treated at 115 ° C. for 60 seconds.
[0069]
Next, the semiconductor substrate after the heat treatment was immersed in a 2.38% aqueous solution of tetramethylammonium hydroxide for 60 seconds, and then rinsed with pure water for 60 seconds.
[0070]
The side wall angle of the obtained resist pattern was 88 degrees. This was observed using CD-SEM S-9200 manufactured by Hitachi, Ltd., and the line width of the resist pattern was measured. At this time, the energy of the electron beam was 500 V, the current value was 4 pA, and the threshold value was 50%. The amount of reduction in the line width after the irradiation with the electron beam for 20 seconds was 2 nm or less, which was a value within a range in which there was no problem in the manufacturing process.
[0071]
Embodiment 2. FIG.
First, a silicon dioxide film was formed with a thickness of about 500 nm on a silicon substrate by a CVD method.
[0072]
Next, DUV30J manufactured by Brewer Science was formed as an antireflection film on the silicon dioxide film. Specifically, after a solution of DUV30J was spin-coated on the silicon dioxide film by a spin coater, a heat treatment was performed at 205 ° C. for 90 seconds. The thickness of the obtained DUV30J was about 85 nm.
[0073]
Subsequently, on the anti-reflection film was formed from Clariant _{F 2} resist FX-1000P as a resist film. Specifically, the FX-1000P solution was spin-coated on the antireflection film by a spin coater, and then heat-treated at 150 ° C. for 60 seconds. The film thickness of the obtained FX-1000P was about 100 nm.
[0074]
Next, using the Ekishitekku manufactured aligner _{F 2} micro stepper, line-and-space pattern (line width 100 nm, the space width 100 nm) through a mask having the resist film with exposure light of 17 mJ / cm ² irradiation did. The numerical aperture (NA) of the exposure machine was 0.85, and σ (NA of light source / NA of lens) was 0.70.
[0075]
Next, the exposed silicon substrate was placed in a proximity-type closed oven and heat-treated at 130 ° C. for 90 seconds.
[0076]
Next, the semiconductor substrate after the heat treatment was immersed in a 2.38% aqueous solution of tetramethylammonium hydroxide for 30 seconds, and then rinsed with pure water for 60 seconds.
[0077]
The side wall angle of the obtained resist pattern was 89 degrees. This was observed using CD-SEM S-9200 manufactured by Hitachi, Ltd., and the line width of the resist pattern was measured. At this time, the energy of the electron beam was 500 V, the current value was 4 pA, and the threshold value was 50%. The amount of reduction in the line width after the irradiation with the electron beam for 20 seconds was 2 nm or less, which was a value within a range in which there was no problem in the manufacturing process.
[0078]
【The invention's effect】
According to the present invention, by setting the side wall angle of the resist pattern to 88 degrees to 89 degrees, the amount of line width reduction of the resist pattern generated when irradiating the electron beam by the SEM is within a range in which there is no problem in the manufacturing process. Can be. Therefore, a fine resist pattern can be formed with good dimensional controllability.
[0079]
Further, according to the present invention, KrF excimer laser, even a fine resist corresponding to an ArF excimer laser or F ₂ excimer laser exposure apparatus whose light source, it is possible to form a pattern with good dimensional controllability.
[0080]
Further, according to the present invention, since a good fine resist pattern can be formed, the yield in the semiconductor device manufacturing process can be increased.
[Brief description of the drawings]
FIG. 1 is a view showing an example of a method for forming a resist pattern according to the present invention.
FIG. 2 is a diagram showing an example of a method for forming a resist pattern according to the present invention.
FIG. 3 is a diagram showing an example of a method for forming a resist pattern according to the present invention.
FIG. 4 is a diagram showing an example of a method for forming a resist pattern according to the present invention.
FIG. 5 is a diagram showing an example of a method for forming a resist pattern according to the present invention.
6A and 6B are diagrams illustrating an example of a resist pattern, wherein FIG. 6A is a forward tapered resist pattern, and FIG. 6B is a reverse tapered resist pattern.
FIG. 7 is a diagram illustrating an example of a sidewall angle and a line width reduction amount of a resist pattern.
FIG. 8 is a diagram showing an example of a side wall angle and a line width reduction amount of a resist pattern.
[Explanation of symbols]
1 semiconductor substrate, 2 silicon dioxide film, 3 anti-reflection film, 4 resist film, 5 mask, 6 exposure light, 7, 8, 9 resist pattern.

Claims (9)

Forming a resist film on the substrate to be processed;
Forming a resist pattern latent image by irradiating the resist film with exposure light through a predetermined mask,
Performing a heat treatment on the resist film;
Forming a resist pattern by performing a development process on the resist film, a method for forming a resist pattern,
A method of forming a resist pattern, wherein a side wall angle of the resist pattern is 88 degrees to 89 degrees. The resist pattern forming method according to claim 1, wherein in the step of performing the heat treatment, the size of the side wall angle is controlled by adjusting a heating time and / or a heating temperature. The substrate to be processed has an anti-reflection film, the resist film is formed on the anti-reflection film, and the size of the side wall angle is controlled by adjusting the thickness of the anti-reflection film. 2. The method for forming a resist pattern according to item 1. The method of forming a resist pattern according to claim 1, wherein a line width of the resist pattern is 150 nm or less. The method according to any one of claims 1 to 4, wherein the exposure light is a KrF excimer laser light having a wavelength of 248 nm. 5. The method according to claim 1, wherein the exposure light is ArF excimer laser light having a wavelength of 193 nm. A resist pattern forming method according to any one of claims 1 to 4 wherein the exposure light is F ₂ excimer laser beam having a wavelength of 157 nm. 5. The method according to claim 1, wherein the exposure light is an electron beam. 9. The method for manufacturing a semiconductor device using the method for forming a resist pattern according to claim 1, wherein the substrate to be processed is a semiconductor substrate.

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