Pattern forming method and resist composition

Abstract

To provide a pattern forming method and a resist composition adapted for forming patterns at low exposure levels in lithography with extreme ultraviolet (EUV) or electron beam.SOLUTION: The provided pattern forming method includes the steps of: applying a resist composition onto a substrate; exposing the substrate to extreme ultraviolet light or an electron beam; and developing with a developer. The resist composition contains a compound A represented by the following formula (1) and a solvent. In formula (1), R1 is a hydrogen atom or a methyl group.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pattern forming method and a resist composition.

Background Art

[0002] Lithography using extreme ultraviolet (hereinafter referred to as "EUV") or an electron beam is expected as a high-resolution microfabrication method in the manufacture of semiconductor devices. Patent Document 1 discloses a resist composition capable of forming a resist pattern having good film quality and adhesion to a substrate by application to the above lithography, and a pattern forming method using the resist composition.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the studies of the present inventors, the resist composition and the pattern forming method of Patent Document 1 have room for improvement from the viewpoint of exposure sensitivity to EUV and electron beams. An object of the present invention is to provide a pattern forming method and a resist composition suitable for pattern formation with a low exposure amount in lithography using EUV or an electron beam.

Means for Solving the Problems

[0005] The present inventors have found that zinc (meth)acrylate is suitable for improving exposure sensitivity, and have completed the present invention based on this.

[0006] The present invention includes a step of applying a resist composition onto a substrate, a step of exposing with EUV or an electron beam, and a step of developing using a developer. The resist composition contains a compound A represented by the following formula (1) and a solvent, In the formula (1), R 1 is a hydrogen atom or a methyl group, and provides a patterning method.

Chemical formula

[0007] Furthermore, the present invention contains a compound A represented by the following formula (1) and a solvent, In the formula (1), R 1 is a hydrogen atom or a methyl group, and provides a resist composition.

Chemical formula

Advantages of the Invention

[0008] The technology of the present invention is suitable for pattern formation at low exposure doses in lithography using EUV or electron beams.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0010] The patterning method according to the first aspect of the present invention includes a step of applying a resist composition onto a substrate, a step of exposing with EUV or an electron beam, and a step of developing using a developer. The resist composition contains a compound A represented by the following formula (1) and a solvent. R in the formula (1) 1 is a hydrogen atom or a methyl group.

Chemical formula

[0011] In a second aspect of the present invention, for example, in the pattern formation method according to the first aspect, the exposure dose of the EUV is 20 mJ / cm 2 or less.

[0012] In a third aspect of the present invention, for example, in the pattern formation method according to the first or second aspect, the substrate contains at least one selected from the group consisting of silicon, SiC, nitride semiconductors, GaAs, and AlGaAs.

[0013] In a fourth aspect of the present invention, for example, in the pattern formation method according to any one of the first to third aspects, the substrate has an insulating film, and the resist composition is applied onto the insulating film.

[0014] In a fifth aspect of the present invention, for example, in the pattern formation method according to the fourth aspect, the substrate further has an organic film formed on the insulating film, and the resist composition is applied onto the organic film.

[0015] In a sixth aspect of the present invention, for example, in the pattern formation method according to any one of the first to fifth aspects, the content of the compound A in the resist composition is 0.1% by mass or more and 10% by mass or less.

[0016] In a seventh aspect of the present invention, for example, in the pattern formation method according to any one of the first to sixth aspects, the resist composition contains a resin at a content of less than 1% by mass.

[0017] In the eighth aspect of the present invention, for example, in the pattern forming method according to any one of the first to seventh aspects, the solvent contains glycol ethers.

[0018] In the ninth aspect of the present invention, for example, in the pattern forming method according to any one of the first to eighth aspects, the developer contains 4-methyl-2-pentanol, 1-butanol, isopropanol, ethyl lactate, tetrahydrofuran, dioxane, anisole, or tetramethylammonium hydroxide at a content rate of 10% by mass or more.

[0019] The resist composition according to the tenth aspect of the present invention contains a compound A represented by the following formula (1) and a solvent, R in the formula (1) 1 is a hydrogen atom or a methyl group.

Chemical formula

[0020] In the eleventh aspect of the present invention, for example, in the resist composition according to the tenth aspect, the content rate of the compound A in the resist composition is 0.1% by mass or more and 10% by mass or less.

[0021] In the twelfth aspect of the present invention, for example, the resist composition according to the tenth or eleventh aspect contains a resin at a content rate of less than 1% by mass.

[0022] In the thirteenth aspect of the present invention, for example, in the resist composition according to any one of the tenth to twelfth aspects, the solvent contains glycol ethers.

[0023] In the fourteenth aspect of the present invention, for example, the resist composition according to any one of the tenth to thirteenth aspects is for pattern formation by exposure to EUV or an electron beam.

[0024] Hereinafter, the present invention will be described in detail. However, the present invention is not limited to the embodiments shown below. The present invention can be arbitrarily modified and implemented without departing from the gist of the present invention.

[0025] [Pattern Formation Method] An example of the pattern formation method of this embodiment is shown in FIG. 1. In the pattern formation method of FIG. 1, a step (i) of applying a resist composition 11 onto a substrate 12, a step (ii) of exposing the resist film 13 formed by the application with EUV 14, and a step of developing the exposed resist film (exposed film) 16 using a developer 15 to form a resist pattern 17 are carried out.

[0026] [Step (i)] The resist composition 11 contains a compound A represented by the following formula (1) and a solvent. R in formula (1) 1 is a hydrogen atom or a methyl group. The compound A is cured by irradiation with EUV or an electron beam. In other words, the resist composition 11 containing the compound A can function as a negative resist material. According to the study by the present inventors, the compound A has high sensitivity to EUV and electron beams, particularly EUV. For example, even under conditions of low exposure dose, it is suitable for reliable curing of the resist composition 11 and formation of a fine pattern minimum line / space (L / S). [Chemical Formula]

[0027] Zinc (meth)acrylate, which is Compound A, has conventionally been mainly used as a modifier for rubber and resin. Also, the wavelength of EUV is short (usually about 1 to 100 nm), and for lithography, the use of EUV with a very short wavelength of 13.5 nm has been put into practical use. EUV having the above wavelength is absorbed by almost all substances. Therefore, it is difficult to predict the curing characteristics of the compound with respect to EUV when it is made into a resist composition. That the resist composition 11 containing Compound A has the above actions, particularly high sensitivity to EUV, has been found for the first time by the studies of the present inventors. In this specification, (meth)acrylic acid means acrylic acid or methacrylic acid.

[0028] The content rate of Compound A in the resist composition 11 is, for example, 0.1 mass% or more and 10 mass% or less. The upper limit of the content rate may be 9 mass% or less, 8 mass% or less, or even 7 mass% or less. The lower limit of the content rate may be 0.5 mass% or more, 1 mass% or more, 2 mass% or more, 3 mass% or more, or even 4 mass% or more.

[0029] Examples of solvents that the resist composition 11 may contain are organic solvents. Examples of organic solvents include alcohols such as ethanol, isopropanol, and 1-butanol; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; glycol ethers such as butanediol monomethyl ether, propylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, propylene glycol monomethoxymethyl ether, propylene glycol monoacetate, and propylene glycol monomethyl ether acetate (PGMEA); ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-amyl ketone, methyl isoamyl ketone, and 2-heptanone; esters such as ethyl acetate, propyl acetate, butyl acetate, methyl lactate, ethyl lactate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl methoxypropionate, methyl ethoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethyl benzene, diethyl benzene, isopropyl benzene, amyl benzene, toluene, xylene, and trimethyl benzene; lactones such as γ-butyrolactone; cyclic ethers such as dioxane; amines such as N,N-dimethylacetamide; and halogens such as chloroform and methylene chloride. The resist composition 11 may contain one or more organic solvents as the solvent. The resist composition 11 may contain one or more organic solvents as the solvent.

[0030] The solvent may contain glycol ethers. A solvent containing glycol ethers can contribute to good pattern formation at low exposure doses in lithography using EUV or an electron beam. A preferred example of glycol ethers is PGMEA. The solvent may be a mixed solvent containing glycol ethers and halogens. An example of the mixed solvent is a solvent containing chloroform and PGMEA.

[0031] A resin can be blended into the resist composition 11. In this specification, the resin means an organic polymer having a weight average molecular weight (Mw) of 2000 or more. The content rate of the resin in the resist composition 11 is preferably less than 1% by mass, and may be 0.7% by mass or less, 0.5% by mass or less, 0.3% by mass or less, 0.1% by mass or less, and even 0.05% by mass or less. The resist composition 11 may not contain a resin. The resist composition 11 may contain a resin at a content rate of less than 1% by mass. The resin may be a known resin that a conventional resist composition can contain. The weight average molecular weight of the resin can be specified as a value in terms of polystyrene by gel permeation chromatography (GPC).

[0032] The resist composition 11 may not substantially contain an acid generator. In other words, the resist composition 11 may be a non-chemically amplified resist composition. In this specification, not substantially containing means that the content rate is, for example, 0.1% by mass or less, preferably 0.05% by mass or less, and more preferably 0.01% by mass or less.

[0033] Examples of the substrate 12 are substrates containing at least one selected from the group consisting of silicon (Si), SiC, nitride semiconductors, GaAs, and AlGaAs. However, the substrate 12 is not limited to the above examples.

[0034] The substrate 12 may have an insulating film, and the resist composition 11 may be applied onto the insulating film of the substrate 12 having the insulating film. In this case, the insulating film constitutes the coating surface of the resist composition 11 on the substrate 12. The insulating film is preferably a film that can be processed into a desired pattern by dry etching or the like. Examples of the insulating film are a polysilicon thin film, a metal thin film, a Si oxide film, a Si nitride film, and a Si oxynitride film. The insulating film may be a multilayer film, for example, a laminated film of a polysilicon thin film and a metal thin film. The substrate 12 may further have an organic film formed on the insulating film, and the resist composition 11 may be applied onto the organic film of the substrate 12 having the organic film. In this case, the organic film constitutes the coating surface of the resist composition 11 on the substrate 12. The organic film may be a known film that a substrate capable of performing pattern formation by coating, exposure, and development of the resist composition may have. An example of the organic film is a spin-on carbon (SOC) film used as a hard mask.

[0035] The shape and dimensions of the substrate 12 are not limited. The substrate 12 can have any shape and dimensions.

[0036] Examples of the method for applying the resist composition 11 onto the substrate 12 are an inkjet method, a spray method, a spin coating method, a dip coating method, and a roll coating method. However, the coating method is not limited to the above examples as long as pattern formation through steps (i) to (iii) is possible. The spin coating method is particularly suitable for forming a uniform coating film.

[0037] The coating amount of the resist composition 11 in step (i) can be adjusted, for example, so that the resist film 13 to be exposed in step (ii) has a desired thickness.

[0038] The resist film 13 can be formed, for example, by drying the coating film of the resist composition 11 formed on the substrate 12. Heating may be used in combination for drying. The heating temperature in the case of using in combination is, for example, 7 It is 0°C or higher, and may be 80°C or higher, further 90°C or higher. The upper limit of the heating temperature is, for example, 300°C or lower, may be 250°C or lower, further 200°C or lower. Heating including two or more different conditions may be carried out. The heating time is, for example, 10 seconds or longer, may be 20 seconds or longer, further 30 seconds or longer. The upper limit of the heating time is, for example, 300 seconds or lower, may be 200 seconds or lower, further 150 seconds or lower. Drying may be carried out under any of reduced pressure, normal pressure, and increased pressure conditions, and may be carried out in an inert atmosphere. Drying is preferably carried out so that the remaining amount of the solvent in the resist film 13 becomes as small as possible, for example, 1000 ppm or less (by mass).

[0039] The thickness of the resist film 13 is, for example, 1 to 200 nm, and may be 2 to 100 nm, further 5 to 50 nm.

[0040] <Step (ii)> In step (ii), the resist film 13 formed through step (i) is exposed with EUV 14. Through the exposure, an exposed film 16 in which the exposed portion of the resist film 13 is cured is usually formed.

[0041] The wavelength of EUV 14 is, for example, 1 to 100 nm, and may be 75 nm or lower, 50 nm or lower, 40 nm or lower, 30 nm or lower, 20 nm or lower, further 15 nm or lower. The wavelength of EUV may be 13.5 nm.

[0042] The exposure amount of EUV 14 to the resist film 13 is, for example, 0.1 to 100 mJ / cm 2 It is. The upper limit of the exposure amount is 75 mJ / cm 2 or lower, 50 mJ / cm 2 or lower, 40 mJ / cm 2 or lower, 30 mJ / cm 2 or lower, 20 mJ / cm 2 or lower, 15 mJ / cm 2 or lower, 10 mJ / cm 2 or lower, further 5 mJ / cm 2 or lower. The lower limit of the exposure amount is 0.2 mJ / cm2 Above, 0.3 mJ / cm 2 Above, 0.4 mJ / cm 2 Above, 0.5 mJ / cm 2 Above, 0.7 mJ / cm 2 Above, 1 mJ / cm 2 Above, 1.2 mJ / cm 2 Above, and even 1.5 mJ / cm 2 It may be above. The resist composition 11 used in the pattern formation method of this embodiment has high sensitivity to EUV14. Therefore, 20 mJ / cm 2 Below, 15 mJ / cm 2 Below, and even 10 mJ / cm 2 When exposing at a low exposure dose of below, the pattern formation method of this embodiment is particularly advantageous.

[0043] Examples of the light source of EUV14 are EUV exposure light sources (LPP) that extract EUV from plasma generated by irradiating a target such as tin, tin compounds, and xenon with laser light; EUV exposure light sources (DPP) that extract EUV from plasma obtained by generating a high-voltage discharge in the presence of tin, tin compounds, or xenon near electrodes made of tungsten, silicon carbide, etc., EUV exposure light sources that extract EUV from plasma generated by a discharge generated by irradiating a target with laser light, and EUV exposure light sources that extract EUV from a synchrotron radiation light source. However, the light source of EUV14 is not limited to the above examples. For the exposure of the resist film 13 to EUV14, a known EUV exposure apparatus can be used.

[0044] The light for exposing the resist film 13 may be an electron beam. The exposure dose of the electron beam to the resist film 13 is, for example, 10 μC / cm 2 Above, and 20 μC / cm 2 Above, and even 50 μC / cm 2 Above, and it may be above. The upper limit of the exposure dose is, for example, 10000 μC / cm 2 Below, and 5000 μC / cm 2 Below, and even 2500 μC / cm 2The following may be applicable. For the exposure of the resist film 13 to electron beams, known radiation sources and electron beam exposure apparatuses can be used.

[0045] <Step (iii)> In step (iii), the exposed film 16 formed through step (ii) is developed. A developer 15 can be used for development. Through development, the unexposed portions of the exposed film 16 are removed. Through step (iii), a resist pattern 17 is formed.

[0046] The developer 16 usually contains a solvent. The solvent that can be used for the developer 16 is not limited as long as it can remove the unexposed portions of the exposed film 16. The developer 16 may contain 4-methyl-2-pentanol, 1-butanol, isopropanol, ethyl lactate, tetrahydrofuran, dioxane, anisole, or tetramethylammonium hydroxide. The content rate of the above-exemplified solvents in the developer 16 may each be 10% by mass or more. The developer 16 may be the solvent of the resist composition 11.

[0047] The developer 16 may further contain additives such as a viscosity modifier, solubilization aid, and surfactant.

[0048] The development time may be, for example, 10 seconds or more, 20 seconds or more, and even 30 seconds or more. The upper limit of the development time may be, for example, 300 seconds or less, 200 seconds or less, and even 100 seconds or less.

[0049] Development can be carried out, for example, by the dipping method, paddle method, or spray method. However, the method of development is not limited to the above examples. Known methods can be applied to development.

[0050] The line width L of the resist pattern 17 is, for example, 500 nm or less, and may be 400 nm or less, 300 nm or less, 250 nm or less, 200 nm or less, 150 nm or less, 100 nm or less, 75 nm or less, or even 50 nm or less. The lower limit of the line width L is, for example, 5 nm or more, or even 10 nm or more. The space width S of the resist pattern 17 is, for example, 500 nm or less, and may be 400 nm or less, 300 nm or less, 250 nm or less, 200 nm or less, 150 nm or less, 100 nm or less, 75 nm or less, or even 50 nm or less. The lower limit of the space width S is, for example, 5 nm or more, or even 10 nm or more. The minimum pattern width (L / S) of the resist pattern 17 can also be within the above range.

[0051] The thickness of the resist pattern 17 is, for example, 10 nm or more, and may be 20 nm or more, 30 nm or more, or even 40 nm or more. The upper limit of the thickness is, for example, 100 nm or less, and may be 80 nm or less, 70 nm or less, 60 nm or less, or even 50 nm or less. The thickness of the resist pattern 17 may be determined in consideration of the minimum processing dimension of the pattern to be formed. The resist composition 11 is highly sensitive and is also suitable for forming a resist pattern 17 having a thickness within the above range. Further, being highly sensitive can contribute to forming a resist pattern 17 having a thickness within the above range under conditions of low exposure dose.

[0052] The pattern formation method of the present invention may further include any arbitrary step other than those described above. Examples of steps that can be further included are a step of baking the exposure film 16 formed through step (ii) (step (iv)), and a step of hard baking the developed resist film 13 formed through step (iii) (step (v)). Step (iv) may be carried out between step (ii) and step (iii). Step (v) is usually carried out after step (iii).

[0053] The heating temperature in step (iv) and step (v) is, for example, 70 °C or higher, and may be 90 °C or higher, or even 110 °C or higher. The upper limit of the heating temperature is, for example, 300 °C or lower, and may be 250 °C or lower, or even 200 °C or lower. Heating including two or more different conditions may be performed. The heating time is, for example, 10 seconds or longer, and may be 30 seconds or longer, or even 60 seconds or longer. The upper limit of the heating time is, for example, 300 seconds or shorter, and may be 150 seconds or shorter, or even 120 seconds or shorter.

[0054] [Resist composition] The resist composition 11 of this embodiment contains a compound A represented by the following formula (1) and a solvent. R in formula (1) 1 is a hydrogen atom or a methyl group. [Chemical formula]

[0055] The resist composition 11 may have the same configuration as the resist composition 11 described above in the description of the pattern formation method of this embodiment, including preferred embodiments. For example, the content of compound A in the resist composition 11 may be 0.1% by mass or more and 10% by mass or less. The resist composition 11 may contain a resin at a content of less than 1% by mass.

[0056] Examples of the solvent that the resist composition 11 may contain are the same as the examples of the solvent that the resist composition 11 described above in the description of the pattern formation method of this embodiment may contain. For example, the solvent may contain glycol ethers.

[0057] The resist composition 11 can be used for pattern formation by exposure to EUV or electron beam. In other words, the resist composition 11 may be for pattern formation by exposure to EUV or electron beam. However, the resist composition 11 may also be used for pattern formation by exposure to other energy rays other than EUV and electron beam. Also, it can be used for applications other than pattern formation.

[0058] The resist composition 11 can be used, for example, in the manufacture of semiconductor devices and as a mask pattern forming material. However, the applications of the resist composition 11 are not limited to the above examples.

[0059] The resist composition 11 can be produced, for example, by mixing Compound A and a solvent. By mixing, a resist composition 11 in which Compound A is dispersed and / or dissolved in the solvent can be formed. However, as long as the resist composition 11 is obtained, the production method is not limited to the above example.

Examples

[0060] Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to the examples shown below.

[0061] (Example 1) Zinc methacrylate (R 1 corresponding to Compound A where R is a methyl group) was dissolved in a mixed solvent of chloroform / PGMEA (volume ratio 9:1) so that the concentration of Compound A was 15 mg / mL to prepare a solution-like resist composition. Next, the prepared resist composition was spin-coated on a Si substrate and dried to form a resist film with a thickness of about 50 nm. Next, the formed resist film was exposed and cured with EUV having a wavelength of 13.5 nm taken out from the beamline of the synchrotron installed at the Paul Scherrer Institute (PSI). The exposure dose was varied in the range of 1.5 to 100 mJ / cm 2 . After exposure, the resist film (exposed film) was developed by immersing it in 1-butanol for 30 seconds. The thickness of the resist film after development was measured by an atomic force microscope (AFM), and the relationship between the thickness of the resist film remaining on the substrate and the exposure dose was evaluated. The contrast curve obtained by the evaluation is shown in Figure 2. As shown in Figure 2, even at the minimum exposure dose of 1.5 mJ / cm 2 , the resist composition was sufficiently cured, and it was confirmed that the film thickness almost the same as that of the resist film before exposure could be maintained even after development.

[0062] (Comparative Example 1) The compound shown in the following formula (2) was dissolved in benzotrifluoride so that the concentration of the compound became 15 mg / mL to prepare a resist composition in solution form. Next, the prepared resist composition was applied onto a Si substrate by spin coating to form a resist film with a thickness of about 30 nm. Note that the coating surface of the resist composition on the substrate was hydrophobized (HMDS treatment) in advance to enhance the adhesion between the substrate and the resist film. Next, in the same manner as in Example 1, the formed resist film was exposed to EUV and cured. After exposure, the resist film (exposed film) was developed by immersing it in light petroleum ether for 30 seconds. The thickness of the resist film after development was measured by AFM, and the relationship between the thickness of the resist film remaining on the substrate and the exposure dose was evaluated. The contrast curve obtained by the evaluation is shown in FIG. 2. As shown in FIG. 2, at an exposure dose of 20 mJ / cm 2 Hereinafter, particularly at 10 mJ / cm 2 It was confirmed that the curing of the resist composition was not sufficient hereinafter, and the thickness after development decreased compared to that before exposure. [Chemical formula]

[0063] (Comparative Example 2) The compound shown in the following formula (3) and the compound shown in the following formula (4) were mixed in a molar ratio of 1:2 in dichloromethane and stirred for 1 hour. Next, the obtained solution was depressurized to distill off the solvent, and a colorless solid was obtained. Next, the obtained solid was dissolved in methyl ethyl ketone to prepare a resist composition in solution form with a concentration of 15 mg / mL. Next, the prepared resist composition was applied onto a Si substrate by spin coating to form a resist film with a thickness of about 30 nm. Next, in the same manner as in Example 1, the formed resist film was exposed to EUV. After exposure, it was immersed in light petroleum ether for 30 seconds, and after immersion, ethylbenzene was flowed onto the side of the resist film (exposed film) for 5 seconds for development. The thickness of the resist film after development was measured by AFM, and the relationship between the thickness of the resist film remaining on the substrate and the exposure dose was evaluated. The contrast curve obtained by the evaluation is shown in FIG. 2. As shown in FIG. 2, at an exposure dose of 20 mJ / cm 2 Hereinafter, particularly at 10 mJ / cm2 It was confirmed that the curing of the resist composition was insufficient below, and the thickness after development had decreased compared to before exposure.

[0064]

Chemical formula

[0065]

Chemical formula

[0066] [Pattern evaluation] Zinc methacrylate (R 1 corresponding to compound A where R is a methyl group) was dissolved in a mixed solvent of chloroform / PGMEA (volume ratio 9:1) so that the concentration of compound A became 10 mg / mL to prepare a solution-like resist composition. Next, the prepared resist composition was spin-coated on a Si substrate to form a resist film with a thickness of about 20 nm. Next, the formed resist film was exposed with EUV having a wavelength of 13.5 nm taken out from the beamline of the synchrotron installed in PSI. The exposure dose was varied in the range of 5 - 15 mJ / cm 2 . Also, the exposure was carried out in a line-and-space pattern with a width of 50 nm by the interference exposure method. After exposure, the resist film (exposed film) was developed by immersing it in 1-butanol for 30 seconds, and further hard-baked at 120 °C to form a negative-type resist pattern. An observation image by AFM of the formed pattern shape is shown in Figure 3. As shown in Figure 3, it was confirmed that a resist pattern with a minimum pattern width L / S = 50 nm / 50 nm could be formed even at an exposure dose of 5 mJ / cm 2 .

Industrial applicability

[0067] The pattern formation method and resist composition of the present invention are suitable for application to lithography using EUV and electron beams, particularly EUV.

Explanation of symbols

[0068] 11 Resist composition 12 Substrate 13 Resist film 14 Extreme ultraviolet (EUV) 15 Developer 16 Resist film after exposure (exposed film) 17 Resist pattern

Claims

1. A method of forming a pattern, comprising: applying a resist composition onto a substrate; exposing the resist composition to extreme ultraviolet light or an electron beam; and developing the resist composition using a developer. The resist composition contains a compound A represented by the following formula (1) and a solvent. R in the formula (1) 1 is a hydrogen atom or a methyl group, A method of forming a pattern. 【Chemical 1】

2. The exposure dose of the extreme ultraviolet light is 20 mJ / cm 2 The pattern forming method according to claim 1, wherein the exposure dose is 20 mJ / cm or less.

3. The method of forming a pattern according to claim 1, wherein the substrate contains at least one selected from the group consisting of silicon, SiC, a nitride semiconductor, GaAs, and AlGaAs.

4. The substrate has an insulating film, and the resist composition is applied onto the insulating film. The method of forming a pattern according to claim 1.

5. The substrate further has an organic film formed on the insulating film, and the resist composition is applied onto the organic film. The method of forming a pattern according to claim 4.

6. The method of forming a pattern according to claim 1, wherein the content of the compound A in the resist composition is 0.1% by mass or more and 10% by mass or less.

7. The method of forming a pattern according to claim 1, wherein the resist composition contains a resin at a content of less than 1% by mass.

8. The method of forming a pattern according to claim 1, wherein the solvent contains glycol ethers.

9. The method of forming a pattern according to claim 1, wherein the developer contains 4-methyl-2-pentanol, 1-butanol, isopropanol, ethyl lactate, tetrahydrofuran, dioxane, anisole, or tetramethylammonium hydroxide at a content of 10% by mass or more.

10. A resist composition containing a compound A represented by the following formula (1) and a solvent. R in the formula (1) above 1 is a hydrogen atom or a methyl group, A resist composition. 【Chemical 2】

11. The resist composition according to claim 10, wherein the content of the compound A in the resist composition is 0.1% by mass or more and 10% by mass or less.

12. The resist composition according to claim 10, containing a resin at a content of less than 1% by mass.

13. The resist composition according to claim 10, wherein the solvent contains glycol ethers.

14. The resist composition according to claim 10, which is for pattern formation by exposure to extreme ultraviolet light or an electron beam.

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