Composition for forming a resist underlayer film

Abstract

To provide a resist underlayer film formation composition that can suppress the generation of minute granular etching residues. [Solution] A resist underlayer film forming composition containing a polymer having repeating units (1) represented by formula (1) and repeating units (2) other than repeating unit (1). The average particle size of the polymer in the polymer solution containing the polymer is 50 nm or less. TIFF2026053526000042.tif4863 (In formula (1), R 1 R represents a hydrogen atom, a methyl group, or a halogen atom. 2 This represents a trivalent hydrocarbon group with 3 to 6 carbon atoms. However, R 2 The lactone structure containing this compound is a five-membered or six-membered ring.

Description

[Technical Field]

[0001] The present invention relates to a composition for forming a resist underlayer film, a resist underlayer film, a substrate for semiconductor processing, a method for manufacturing a semiconductor device, and a method for forming a pattern. [Background technology]

[0002] Conventionally, microfabrication using lithography with photoresist compositions has been performed in the manufacturing of semiconductor devices. This microfabrication method involves forming a thin film of a photoresist composition on a silicon wafer, irradiating it with active energy rays such as ultraviolet light through a mask pattern on which the semiconductor device pattern is drawn, developing the film, and then etching the silicon wafer using the resulting resist pattern as a protective film.

[0003] However, in recent years, with the increasing integration density of semiconductor devices, the wavelengths of the active energy rays used have tended to shorten from KrF excimer lasers (248 nm) to ArF excimer lasers (193 nm). Consequently, diffuse reflection of the active energy rays from the substrate and the effects of standing waves have become major problems. Therefore, a method of placing an anti-reflective coating (Bottom Anti-Reflective Coating: BARC), which is an underlayer of the resist, between the photoresist and the substrate has become widely considered.

[0004] For example, the applicant has proposed an anti-reflective film forming composition that provides a lithography anti-reflective film with high anti-reflective effect, no intermixing with the resist layer, excellent resist pattern and wide focus depth margin, and a larger dry etching rate compared to the resist (see Patent Document 1). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2003 / 017002 Pamphlet [Overview of the project] [Problems that the invention aims to solve]

[0006] The inventors of the present invention have found that when using the composition described in International Publication No. 2003 / 017002 as a resist underlayer formation composition, minute granular etching residue may be generated when etching the resist underlayer obtained from said resist underlayer formation composition. The generation of etching residue can reduce the yield of semiconductor devices.

[0007] The present invention aims to provide a resist underlayer film formation composition, a resist underlayer film, a semiconductor processing substrate, a semiconductor device manufacturing method, and a pattern formation method that can suppress the generation of minute granular etching residues. [Means for solving the problem]

[0008] The inventors of this invention conducted diligent research to solve the above problems and, as a result, found that they could solve the above problems, and completed the present invention having the following gist. In other words, the present invention encompasses the following: [1] A polymer having a repeating unit (1) represented by the following formula (1) and repeating units (2) other than the repeating unit (1), and a solvent, The average particle size of the polymer in the polymer solution containing the polymer is 50 nm or less. A composition for forming a resist underlayer film. [ka] (In formula (1), R 1 R represents a hydrogen atom, a methyl group, or a halogen atom. 2 This represents a trivalent hydrocarbon group with 3 to 6 carbon atoms. However, R 2 The lactone structure containing this compound is a five-membered or six-membered ring. [2] The resist underlayer film forming composition according to [1], wherein the repeating unit (2) comprises a repeating unit (2A) represented by the following formula (2A). [Chemical formula] (In formula (2A), R 11 represents a hydrogen atom, a methyl group, or a halogen atom, and Q 1 represents a single bond or a divalent linking group, and R 12 represents a hydrogen atom or a monovalent organic group.) [3] The resist lower layer film forming composition according to [1] or [2], wherein the repeating unit (2) contains a repeating unit (2A-1) represented by the following formula (2A-1) and a repeating unit (2A-2) represented by the following formula (2A-2). [Chemical formula] (In formula (2A-1), X 21 represents -O- or -N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). R 21 represents a hydrogen atom, a methyl group, or a halogen atom, and R 22 represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms.) In formula (2A-2), X 31 represents -O- or -N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). R 31 represents a hydrogen atom, a methyl group, or a halogen atom, and R 32 represents a substituted or unsubstituted aralkyl group, a substituted or unsubstituted carbocyclic aromatic group, or a substituted or unsubstituted heterocyclic aromatic group.) [4] In the polymer, the weight ratio of the repeating unit (1) to all repeating units is 1 to 75% by weight, and in the polymer, the total weight ratio of the repeating unit (2A-1) and the repeating unit (2A-2) to all repeating units is 25 to 99% by weight, The resist lower layer film forming composition according to [3]. [5] The resist lower layer film forming composition according to any one of [1] to [4], wherein the weight average molecular weight of the polymer is 50,000 or less. [6] A composition for forming a resist underlayer film according to any one of [1] to [5], further comprising a crosslinking agent. [7] A resist underlayer film forming composition according to any one of [1] to [6], further comprising a curing catalyst. A resist underlayer film, which is a cured product of a resist underlayer film forming composition described in any of [1] to [7] [8]. [9] Semiconductor substrate and, [8] The resist underlayer film described above, A semiconductor processing substrate equipped with the following features.

[10] A step of forming a resist underlayer on a semiconductor substrate using a resist underlayer formation composition described in any of [1] to [7], The steps include forming a resist film on the aforementioned resist underlayer film, A method for manufacturing semiconductor devices, including

[11] A step of forming a resist underlayer on a semiconductor substrate using a resist underlayer forming composition described in any of [1] to [7], The steps include forming a resist film on the aforementioned resist underlayer film, The steps include irradiating the resist film with light or an electron beam, then developing the resist film to obtain a resist pattern, A step of etching the resist underlayer film using the resist pattern as a mask, A pattern formation method, including the following. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a resist underlayer film formation composition that can suppress the generation of minute granular etching residues, a resist underlayer film, a semiconductor processing substrate, a method for manufacturing a semiconductor device, and a pattern formation method. [Brief explanation of the drawing]

[0010] [Figure 1A] Figure 1A shows the particle size distribution of sample 1st of the polymer solution from synthesis example 1. [Figure 1B] Figure 1B shows the particle size distribution of sample 2nd of the polymer solution from synthesis example 1. [Figure 1C] Figure 1C shows the particle size distribution of sample 3rd of the polymer solution from synthesis example 1. [Figure 2A] Figure 2A shows the particle size distribution of sample 1st in the polymer solution of synthesis example 2. [Figure 2B] Figure 2B shows the particle size distribution of sample 2nd of the polymer solution from synthesis example 2. [Figure 2C] Figure 2C shows the particle size distribution of sample 3rd of the polymer solution from synthesis example 2. [Modes for carrying out the invention]

[0011] (Composition for forming a resist underlayer film) The present invention's composition for forming a resist underlayer film contains a polymer and a solvent. The resist underlayer film formation composition may contain other components. The average particle size of the polymer in a polymer solution containing the polymer is 50 nm or less.

[0012] The inventors of the present invention have found that when using the composition described in International Publication No. 2003 / 017002 as a resist underlayer formation composition, minute granular etching residue may be generated when etching the resist underlayer obtained from said resist underlayer formation composition. The generation of etching residue can reduce the yield of semiconductor devices. One possible cause of etching residue is metal impurities in the composition. However, our investigation revealed that the fine granular etching residue was not caused by metal impurities. Further investigations by the inventors revealed that the polymer contained in the resist underlayer film forming composition was influencing the fine granular etching residue. It was found that there were parts of the polymer that were difficult to etch, and these were causing the etching residue. The present inventors focused on monomers that constitute polymers and have a lactone structure and polymerizable unsaturated bonds (hereinafter sometimes referred to as "lactone structure-containing monomers"). Generally, in multi-component polymers synthesized by radical polymerization using two or more monomers, the copolymerization reactivity ratios between each monomer differ. As a result, the copolymerization composition ratio of the polymer produced in the early and late stages of polymerization differs, and the final polymer has a compositional distribution. Lactone-containing monomers exhibit a faster polymerization rate in copolymerization compared to other monomers. Therefore, as described in the examples (e.g., Synthesis Examples 1 to 5) of International Publication No. 2003 / 017002, when two or more monomers are mixed together and polymerized according to the composition ratio in the final polymer, it is thought that a relatively large amount of lactone-containing monomers are consumed in the initial stages of polymerization. As a result, repeating units derived from lactone-containing monomers are unevenly distributed in the polymer chain generated in the initial stages of polymerization. When repeating units derived from lactone-containing monomers are unevenly distributed in the polymer chain, the polymer chain becomes more entangled. This is thought to reduce the solubility of the polymer and increase the average particle size of the polymer in the polymer solution. As a result of further investigation, the inventors discovered that by using a polymer with a small average particle size in the polymer solution as the polymer contained in the resist underlayer film forming composition, minute granular etching residue can be suppressed, thus completing the present invention.

[0013] In the present invention, the average particle size of the polymer in the polymer solution containing the polymer is 50 nm or less, preferably 40 nm or less, more preferably 30 nm or less, and particularly preferably 20 nm or less. There are no particular restrictions on the lower limit of the average particle size of the polymer, but it may be 1 nm or larger, 2 nm or larger, or 5 nm or larger. The average particle size of polymers in a polymer solution can be determined by dynamic light scattering measurements. Dynamic light scattering measurements are performed, for example, using a dynamic light scattering photometer DLS-8000Ar (manufactured by Otsuka Electronics Co., Ltd.). A He-Ne laser (wavelength 633 nm) is used as the incident light, and measurements are taken at a scattering angle of 90° to determine the autocorrelation function. Using the analysis program included with the above measuring instrument, the average particle size and polydispersity index can be determined from the obtained autocorrelation function by cumulant analysis. Particle size distribution analysis can be performed using the Contin method. Examples of the polyvariance index of the present invention include 0.25 or less, 0.24 or less, 0.23 or less, 0.22 or less, 0.21 or less, 0.20 or less, 0.18 or less, and 0.15 or less.

[0014] The number of minute granular etching residues (Cone defect count) shown by the composition of the present invention is, for example, 2500 or less, 2300 or less, 2000 or less, 1500 or less, 1000 or less, 800 or less, 700 or less, 600 or less, 500 or less, 400 or less, 300 or less, 200 or less, 100 or less, 80 or less, 70 or less, 50 or less, 30 or less, 20 or less, and 10 or less, as determined by the Etching defect evaluation method shown in the examples.

[0015] The solvent in the polymer solution is preferably the solvent used for polymer polymerization. Therefore, it is preferable to use the polymer solution obtained by polymerizing monomers under a solvent as the polymer solution for measuring the average particle size. Examples of solvents used for polymer polymerization include polyhydric alcohol derivatives. Examples of polyhydric alcohol derivatives include ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate.

[0016] From the viewpoint of measurement reliability, the polymer concentration in the polymer solution is preferably 10 to 30% by mass. With a polymer solution of this concentration, some degree of entanglement between polymer chains occurs in the polymer solution, making it easier to obtain results that correlate with the generation of fine granular etching residue. Typically, the amount of polymer in resist underlayer formation compositions is small, so even when attempting to measure the average particle size of the polymer using a resist underlayer formation composition, it is difficult to obtain results that correlate with the generation of fine granular etching residue. This is thought to be because, at low polymer concentrations, entanglement between polymer chains is less likely to occur. Furthermore, resist underlayer formation compositions as products may also contain components other than polymers (e.g., crosslinking agents, curing catalysts, and other components), and when dynamic light scattering measurements are performed on resist underlayer formation compositions, the resulting particle size distribution contains a mixture of polymer particle size distributions and particle size distributions of non-polymer components, making it difficult to obtain results that correlate with the generation of fine granular etching residue. From this perspective, when measuring the average particle size in the present invention, it is suitable to use a polymer solution, and it is more suitable to use a polymer solution with a polymer concentration of 10 to 30% by mass. Furthermore, it is suitable to use a polymer solution in which only the polymer is dissolved in a solvent, without containing crosslinking agents, curing catalysts, etc.

[0017] <polymer> A polymer has repeating units (1) represented by the following formula (1). A polymer also has repeating units (2) other than repeating unit (1). In this respect, a polymer can be said to be a copolymer. [ka] (In formula (1), R 1 R represents a hydrogen atom, a methyl group, or a halogen atom. 2 This represents a trivalent hydrocarbon group with 3 to 6 carbon atoms. However, R 2 The lactone structure containing this compound is a five-membered or six-membered ring.

[0018] In this specification, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0019] Examples of repeating units (1) represented by equation (1) include the repeating units represented by equations (1-1) to (1-3) below. [ka] (In formulas (1-1) to (1-3), R 1 (This represents a hydrogen atom, a methyl group, or a halogen atom.)

[0020] R in equation (1) and equations (1-1) to (1-3) 1 A methyl group is preferred as the component.

[0021] The repeating unit (2) is not particularly limited as long as it is a repeating unit other than the repeating unit (1) represented by formula (1), but it is preferable to include the repeating unit (2A) represented by the following formula (2A). [ka] (In formula (2A), R 11 Q represents a hydrogen atom, a methyl group, or a halogen atom. 1 R represents a single bond or a divalent linking group. 12 (This represents a hydrogen atom or a monovalent organic group.)

[0022] Q 1 The divalent linking group in is not particularly limited, but examples include -C(=O)O-, -O-, -C(=O)-N(-R)- (where R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), -NHC(=O)NH- (urea bond), -NHC(=O)O- (urethane bond), -C(=O)-, -S-, -SO-, -NH-, etc.

[0023] R 12 The monovalent organic group in this context is not particularly limited, but examples include monovalent organic groups having 1 to 30 carbon atoms. R12 Examples of monovalent organic groups in this context include substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms, substituted or unsubstituted aralkyl groups, substituted or unsubstituted carbocyclic aromatic groups, and substituted or unsubstituted heterocyclic aromatic groups. Examples of these substituents include halogen atoms, hydroxyl groups, carboxyl groups, alkoxy groups, cyano groups, nitro groups, and amino groups. Examples of alkoxy groups include alkoxy groups having 1 to 6 carbon atoms. Note that the "1 to 10 carbon atoms" in "substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms" does not include the number of carbon atoms of substituents.

[0024] Examples of alkyl groups in substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, cyclopropyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, cyclobutyl group, 1-methyl-cyclopropyl group, 2-methyl-cyclopropyl group, n-pentyl group, 1-methyl-n-butyl group, 2-methyl-n-butyl group, 3-methyl-n-butyl group, 1,1-dimethyl-n-propyl group, 1,2-dimethyl-n-propyl group, and 2,2-dimethyl-n-propyl group. Pyr group, 1-ethyl-n-propyl group, cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl -n-butyl group, 2,2-dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclo Butyl group, 3-ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2,Examples include 3-trimethylcyclopropyl group, 1-ethyl-2-methylcyclopropyl group, 2-ethyl-1-methylcyclopropyl group, 2-ethyl-2-methylcyclopropyl group, 2-ethyl-3-methylcyclopropyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, and icodecyl group.

[0025] Examples of substituted or unsubstituted aralkyl groups include benzyl, phenethyl, naphthylmethyl, and anthrylmethyl groups.

[0026] Examples of substituted or unsubstituted carbocyclic aromatic groups include phenyl, naphthyl, anthryl, and phenanthryl groups. Examples of the number of carbon atoms in a substituted or unsubstituted carbocyclic aromatic group include 6 to 30. Examples of substituted or unsubstituted carbocyclic aromatic groups include phenyl group, o-methylphenyl group, m-methylphenyl group, p-methylphenyl group, o-chlorophenyl group, m-chlorophenyl group, p-chlorophenyl group, o-fluorophenyl group, p-fluorophenyl group, o-methoxyphenyl group, p-methoxyphenyl group, p-nitrophenyl group, p-cyanophenyl group, α-naphthyl group, β-naphthyl group, o-biphenylyl group, m-biphenylyl group, p-biphenylyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, and 9-phenanthryl group.

[0027] Examples of heterocyclic aromatic groups in substituted or unsubstituted heterocyclic aromatic groups include pyridyl groups, quinolinyl groups, and quinoxalinyl groups.

[0028] The repeating unit (2) preferably includes a repeating unit (2A-1) represented by the following formula (2A-1) and a repeating unit (2A-2) represented by the following formula (2A-2). [ka] (In formula (2A-1), X 21 R represents -O- or -N(-R)- (where R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). 21 R represents a hydrogen atom, a methyl group, or a halogen atom. 22 This represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms. In formula (2A-2), X 31 R represents -O- or -N(-R)- (where R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). 31 R represents a hydrogen atom, a methyl group, or a halogen atom. 32 (This represents a substituted or unsubstituted aralkyl group, a substituted or unsubstituted carbocyclic aromatic group, or a substituted or unsubstituted heterocyclic aromatic group.)

[0029] R 22 Specific examples of substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms in R 12 Specific examples of substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms are given in the explanation. R 32 Specific examples of substituted or unsubstituted aralkyl groups, substituted or unsubstituted carbocyclic aromatic groups, and substituted or unsubstituted heterocyclic aromatic groups in R include, for example, 12 Specific examples of substituted or unsubstituted aralkyl groups, substituted or unsubstituted carbocyclic aromatic groups, and substituted or unsubstituted heterocyclic aromatic groups are given in the explanation.

[0030] R in equation (2A) 11 , R in equation (2A-1) 21 , and R in equation (2A-2) 31 A methyl group is preferred as the component.

[0031] The proportion of repeating units (1) in the polymer is not particularly limited. The weight ratio of repeating unit (1) to the total number of repeating units in the polymer is preferably 1 to 75% by weight, more preferably 5 to 60% by weight, and particularly preferably 10 to 45% by weight. The weight ratio of repeating unit (2) to the total repeating units in the polymer is not particularly limited, but is preferably 25 to 99% by weight, more preferably 40 to 95% by weight, and particularly preferably 55 to 90% by weight. The total weight ratio of repeating units (2A-1) and (2A-2) to the total number of repeating units in the polymer is not particularly limited, but is preferably 25 to 99% by weight, more preferably 40 to 95% by weight, and particularly preferably 55 to 90% by weight.

[0032] The molecular weight of the polymer is not particularly limited. The weight-average molecular weight of the polymer measured by gel permeation chromatography is not particularly limited, but is preferably 100,000 or less, more preferably 50,000 or less, and particularly preferably 30,000 or less. There are no particular restrictions on the lower limit of the weight-average molecular weight of the polymer, but a weight-average molecular weight of 5,000 or more is preferred.

[0033] <<Method for producing polymers>> The polymer is obtained by radical polymerization of two or more monomers. One of the two or more monomers is a monomer represented by the following formula (1'). The polymer manufacturing method is one that results in a small average particle size of the polymer in the polymer solution. Examples of such manufacturing methods include the polymer manufacturing method described in International Publication No. 2012 / 053434. Specifically, examples include the polymerization methods (Z1) and (Z2) described in sections

[0062] to

[0066] of International Publication No. 2012 / 053434. The contents of International Publication No. 2012 / 053434 are incorporated herein to the same extent as if they were fully expressed. Specific examples of polymer manufacturing methods include the polymer manufacturing methods described in Reference Example B-3 and Example B-3 of International Publication No. 2012 / 053434. Here, the monomer represented by the following formula (1') in this specification corresponds to monomer m-1 represented by formula (m-1) in Reference Example B-3 of International Publication No. 2012 / 053434. The monomer represented by the following formula (2A'-1) in this specification corresponds to monomer m-7 represented by formula (m-7) in Reference Example B-3 of International Publication No. 2012 / 053434. The monomer represented by the following formula (2A'-2) in this specification corresponds to monomer m-6 represented by formula (m-6) in Reference Example B-3 of International Publication No. 2012 / 053434. In Reference Example B-3 of International Publication No. 2012 / 053434, the following polymerization is performed to design the composition of solution Uc used in the subsequent process. In the polymerization process, a dropwise solution containing the monomer mixture, solvent, and polymerization initiator is added to the flask from a dropping funnel at a constant rate over 4 hours, while the temperature is maintained at 80°C for 3 hours. After 7 hours from the start of the dropwise addition of the solution, the mixture is cooled to room temperature to stop the reaction. In Reference Example B-3, 0.5 g of the polymerization reaction solution in the flask was sampled at 0.5, 1, 2, 3, 4, 5, 6, and 7 hours after the start of the dropwise addition of the solution, and monomers m-1, m-6, and m-7 were quantified. This allowed the mass of each monomer remaining in the flask at each sampling time to be determined. In Reference Example B-3, the monomer content ratio (polymer composition) of the polymer produced during each reaction time period is determined. In example B-3, the composition x0:y0:z0 of Uc is determined. Based on the results of Reference Example B-3, Example B-3 includes a post-step in which Uc is added dropwise after the main step in which Sa is supplied into the reactor in advance and Tb and polymerization initiator solution are added dropwise. In Example B-3, the composition ratio of monomer m-1, which has a high polymerization rate, in the first composition of Sa supplied to the reaction vessel beforehand is smaller than the composition ratio of monomer m-1 in the target composition. By doing so, in Example B-3, it is possible to avoid monomer m-1 being more ubiquitous in the polymer chain generated in the initial stages of polymerization than in the composition ratio of the target composition. As a result, entanglement of the polymer chain is reduced, and a polymer with a small average particle size in the polymer solution can be obtained.

[0034] The monomer that gives the polymer the repeating unit (1) represented by formula (1) is the monomer represented by the following formula (1'). [ka] (In formula (1'), R 1 , and R 2 These are R in equation (1), respectively. 1 , and R 2 (This is synonymous with...)

[0035] The monomer that gives the polymer the repeating unit represented by formula (1-1) is the monomer represented by the following formula (1'-1). The monomer that gives the polymer the repeating unit represented by formula (1-2) is the monomer represented by the following formula (1'-2). The monomer that gives the polymer the repeating units represented by formula (1-3) is the monomer represented by the following formula (1'-3). [ka] (In formula (1'-1), R 1 This is R in equation (1-1). 1 (This is synonymous with...) (In formula (1'-2), R 1 R in equation (1-2) is 1 (This is synonymous with...) (In formula (1'-3), R 1 R in equation (1-3) is 1 (This is synonymous with...)

[0036] The monomer that gives the polymer the repeating unit (2A) represented by formula (2A) is the monomer represented by the following formula (2A'). The monomer that gives the polymer the repeating unit (2A-1) represented by formula (2A-1) is the monomer represented by the following formula (2A'-1). The monomer that gives the polymer the repeating unit (2A-2) represented by formula (2A-2) is the monomer represented by the following formula (2A'-2). [ka] (In formula (2A'), R 11 , R 12 , and Q 1 These are R in equation (2A), respectively. 11 , R 12 , and Q 1 It is synonymous with [the above]. In formula (2A'-1), R 21 , R 22 , and X 21 These are R in equation (2A-1), respectively. 21 , R 22 , and X 21 It is synonymous with [the above]. In formula (2A'-2), R 31 , R 32 , and X 31 These are R in equation (2A-2), respectively. 31 , R 32 , and X 31 (This is synonymous with...)

[0037] Examples of monomers represented by formula (2A') include acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and styrenes. Examples of acrylic acid esters include substituted or unsubstituted alkyl acrylates with alkyl groups having 1 to 10 carbon atoms, aralkyl esters of acrylic acid, and aryl esters of acrylic acid. Examples of methacrylic acid esters include substituted or unsubstituted alkyl methacrylates with alkyl groups having 1 to 10 carbon atoms, aralkyl esters of methacrylic acid, and aryl esters of methacrylic acid. Examples of acrylamides include N-alkylacrylamide, N-arylacrylamide, N,N-dialkylacrylamide, N,N-diarylacrylamide, N-methyl-N-phenylacrylamide, and N-2-acetamidoethyl-N-acetylacrylamide. Examples of methacrylamides include N-alkylmethacrylamide, N-arylmethacrylamide, N,N-dialkylmethacrylamide, N,N-diarylmethacrylamide, N-methyl-N-phenylmethacrylamide, and N-ethyl-N-phenylmethacrylamide. Examples of vinyl ethers include alkyl vinyl ethers and vinylaryl ethers. Examples of vinyl esters include vinyl butyrate, vinyl isobutyrate, and vinyl trimethyl acetate. Examples of styrenes include styrene, alkylstyrene, alkoxystyrene, halogenated styrene, and carboxystyrene.

[0038] <<<Polymerization initiator>>> Organic peroxides and diazo compounds can be used as polymerization initiators for polymerization.

[0039] Examples of organic peroxides include diacyl peroxides, peroxydicarbonates, peroxyesters, and sulfonates. Examples of diacyl peroxides include diacetyl peroxide, diisobutyl peroxide, didecanoyl peroxide, benzoyl peroxide, and succinate peroxide. Examples of peroxydicarbonates include diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and diallyl peroxydicarbonate. Examples of peroxyesters include tert-butyl peroxyisobutyrate, tert-butyl neodecanate, and cumene peroxyneodecanate. Examples of sulfonates include acetylcyclohexyl sulfonyl peroxide.

[0040] Examples of diazo compounds include 2,2'-azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(4-methoxy-2,4-dimethoxyvaleronitrile), and 2,2'-azobis(2-cyclopropylpropionitrile).

[0041] If polymerization is to be completed in a short time, it is preferable to use a polymerization initiator with a decomposition half-life of 10 hours or less at 80°C. Suitable polymerization initiators include benzoyl peroxide and 2,2'-azobisisobutyronitrile, with 2,2'-azobisisobutyronitrile being more preferred.

[0042] The amount of polymerization initiator used is, for example, 0.0001 to 0.2 equivalents, preferably 0.0005 to 0.1 equivalents, relative to the total amount of monomer used.

[0043] <<<Solvent>>> The solvent used for polymerization is not particularly limited as long as it does not participate in the polymerization reaction and is compatible with the resulting polymer. Examples include aromatic hydrocarbons, alicyclic hydrocarbons, aliphatic hydrocarbons, ketones, ethers, esters, amides, sulfoxides, alcohols, and polyhydric alcohol derivatives. Examples of aromatic hydrocarbons include benzene, toluene, and xylene. Examples of alicyclic hydrocarbons include cyclohexane. Examples of aliphatic hydrocarbons include n-hexane and n-octane. Examples of ketones include acetone, methyl ethyl ketone, and cyclohexanone. Examples of ethers include tetrahydrofuran and dioxane. Examples of esters include ethyl acetate and butyl acetate. Examples of amides include N,N-dimethylformamide and N,N-dimethylacetamide. Examples of sulfoxides include dimethyl sulfoxide. Examples of alcohols include methanol and ethanol. Examples of polyhydric alcohol derivatives include ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate. These can be used individually or in combination of two or more types.

[0044] The polymerization temperature is not particularly limited as long as it is within a temperature range where side reactions such as transfer reactions or termination reactions do not occur, and the monomer is consumed and polymerization is completed. However, it is preferable that the polymerization is carried out in a temperature range of -100°C or higher and below the boiling point of the solvent. Furthermore, the concentration of the monomer in the solvent is not particularly limited, but is usually 1 to 40% by mass, and preferably 10 to 30% by weight. The polymerization reaction time can be selected as needed, but it is usually in the range of 2 to 50 hours.

[0045] The polymer content in the resist underlayer film forming composition is not particularly limited, but is preferably 30% to 95% by mass, more preferably 50% to 90% by mass, and particularly preferably 60% to 85% by mass relative to the film constituent components. Film components are the components remaining after removing volatile components (solvents) from the resist film-forming composition.

[0046] <Crosslinking agent> The composition for forming the resist underlayer film preferably contains a crosslinking agent. A crosslinking agent included as an optional component in a resist underlayer film formation composition has, for example, a functional group that reacts on its own. Examples of crosslinking agents include hexamethoxymethylmelamine, tetramethoxymethylbenzoguanamine, 1,3,4,6-tetrakis(methoxymethyl)glycoluryl (tetramethoxymethylglycoluryl) (POWDERLINK® 1174), 1,3,4,6-tetrakis(butoxymethyl)glycoluryl, 1,3,4,6-tetrakis(hydroxymethyl)glycoluryl, 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetrakis(butoxymethyl)urea, and 1,1,3,3-tetrakis(methoxymethyl)urea.

[0047] Furthermore, the crosslinking agent may be a nitrogen-containing compound having 2 to 6 substituents represented by the following formula (1d) that bond to a nitrogen atom in one molecule, as described in International Publication No. 2017 / 187969.

[0048] [ka] (In formula (1d), R1 represents a methyl group or an ethyl group. * represents a bond that connects to a nitrogen atom.)

[0049] A nitrogen-containing compound having 2 to 6 substituents represented by formula (1d) in one molecule may be a glycoluryl derivative represented by the following formula (1E).

[0050] [ka] (In formula (1E), each of the four R1s independently represents a methyl group or an ethyl group, and R2 and R3 independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.)

[0051] Examples of glycoluryl derivatives represented by formula (1E) include the compounds represented by the following formulas (1E-1) to (1E-6).

[0052] [ka]

[0053] A nitrogen-containing compound having 2 to 6 substituents represented by formula (1d) in one molecule can be obtained by reacting a nitrogen-containing compound having 2 to 6 substituents represented by the following formula (2d) that bond to a nitrogen atom in one molecule with at least one compound represented by the following formula (3d).

[0054] [ka] (In formulas (2d) and (3d), R1 represents a methyl group or an ethyl group, and R4 represents an alkyl group having 1 to 4 carbon atoms. * represents a bond that connects to a nitrogen atom.)

[0055] The glycoluryl derivative represented by formula (1E) is obtained by reacting a glycoluryl derivative represented by the following formula (2E) with at least one compound represented by formula (3d).

[0056] A nitrogen-containing compound having 2 to 6 substituents represented by formula (2d) in one molecule is, for example, a glycoluryl derivative represented by the following formula (2E).

[0057] [ka] (In formula (2E), R2 and R3 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, and R4 each independently represents an alkyl group having 1 to 4 carbon atoms.)

[0058] Examples of glycoluryl derivatives represented by formula (2E) include the compounds represented by formulas (2E-1) to (2E-4) below. Furthermore, examples of compounds represented by formula (3d) include the compounds represented by formulas (3d-1) and (3d-2) below.

[0059] [ka] [ka]

[0060] With regard to nitrogen-containing compounds having 2 to 6 substituents represented by formula (1d) bonded to the aforementioned nitrogen atom in one molecule, the full disclosure in WO2017 / 187969 is incorporated herein by reference.

[0061] Furthermore, the above-mentioned crosslinking agent may be a crosslinkable compound represented by the following formula (G-1) or formula (G-2) as described in International Publication No. 2014 / 208542.

[0062] [ka] (In the formula, Q 1 R indicates a single bond or an m1 valent organic group. 1 and R 4 Each represents an alkyl group having 2 to 10 carbon atoms, or an alkyl group having 2 to 10 carbon atoms having an alkoxy group having 1 to 10 carbon atoms, R 2 and R 5 Each represents either a hydrogen atom or a methyl group, and R 3 and R 6 Each of these represents an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 40 carbon atoms. n1 is an integer between 1 and 3, n2 is an integer between 2 and 5, n3 is an integer between 0 and 3, n4 is an integer between 0 and 4, and 3 is an integer between 6 and 10 (n1 + n2 + n3 + n4). n5 is an integer between 1 and 5 (1 ≤ n5 ≤ 3), n6 is an integer between 1 and 6 (1 ≤ n6 ≤ 4), n7 is an integer between 0 and 7 (0 ≤ n7 ≤ 3), n8 is an integer between 0 and 8 (0 ≤ n8 ≤ 3), and 2 is an integer between 2 and (n5 + n6 + n7 + n8) ≤ 5. m1 represents an integer between 2 and 10.

[0063] The crosslinkable compound represented by formula (G-1) or formula (G-2) above may be obtained by reacting a compound represented by formula (G-3) or formula (G-4) below with a hydroxyl group-containing ether compound or an alcohol having 2 to 10 carbon atoms.

[0064] [ka] (In the formula, Q 2 R indicates a single bond or an m2 valent organic group. 8 , R 9 , R 11 and R 12 Each represents either a hydrogen atom or a methyl group, and R 7 and R 10 Each of these represents an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 40 carbon atoms. n9 represents an integer between 1 ≤ n9 ≤ 3, n10 represents an integer between 2 ≤ n10 ≤ 5, n11 represents an integer between 0 ≤ n11 ≤ 3, n12 represents an integer between 0 ≤ n12 ≤ 3, and 3 represents an integer between 3 ≤ (n9 + n10 + n11 + n12) ≤ 6. n13 represents an integer between 1 ≤ n13 ≤ 3, n14 represents an integer between 1 ≤ n14 ≤ 4, n15 represents an integer between 0 ≤ n15 ≤ 3, n16 represents an integer between 0 ≤ n16 ≤ 3, and 2 represents an integer between 2 ≤ (n13 + n14 + n15 + n16) ≤ 5. m² represents an integer between 2 and 10.

[0065] The compounds represented by formulas (G-1) and (G-2) above can be exemplified as follows.

[0066] [ka]

[0067] [ka]

[0068] [ka]

[0069] [ka]

[0070] [ka]

[0071] The compounds represented by formulas (G-3) and (G-4) can be exemplified below.

[0072] [ka]

[0073] [ka] In the formula, Me represents a methyl group.

[0074] The full disclosure of International Publication No. 2014 / 208542 is incorporated herein by reference.

[0075] When the aforementioned crosslinking agent is used, the content of the crosslinking agent in the resist underlayer film forming composition is, for example, 1% to 50% by mass, preferably 5% to 40% by mass, relative to the polymer.

[0076] <Curing catalyst> The curing catalyst included as an optional component in the resist underlayer film formation composition can be either a thermal acid generator or a photoacid generator, but it is preferable to use a thermal acid generator.

[0077] Examples of thermal acid generators include sulfonic acid compounds and carboxylic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium-p-toluenesulfonate (pyridinium-p-toluenesulfonic acid), pyridinium phenolsulfonic acid, pyridinium-p-hydroxybenzenesulfonic acid (pyridinium salt of p-phenolsulfonic acid), pyridinium-trifluoromethanesulfonic acid, salicylic acid, camphorsulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, and hydroxybenzoic acid.

[0078] Examples of photoacid generators include onium salt compounds, sulfonimide compounds, and disulfonyldiazomethane compounds.

[0079] Examples of iodonium salt compounds include iodonium salt compounds such as diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoron-butanesulfonate, diphenyliodonium perfluoron-octanesulfonate, diphenyliodonium camphor sulfonate, bis(4-tert-butylphenyl)iodonium camphor sulfonate and bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoron-butanesulfonate, triphenylsulfonium camphor sulfonate and triphenylsulfonium trifluoromethanesulfonate.

[0080] Examples of sulfonimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalimide.

[0081] Examples of disulfonyl diazomethane compounds include bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0082] Only one type of curing catalyst may be used, or two or more types may be used in combination.

[0083] When a curing catalyst is used, the content of the curing catalyst is, for example, 0.1% to 50% by mass relative to the crosslinking agent, preferably 1% to 30% by mass.

[0084] <Solvent> As solvents, organic solvents commonly used in semiconductor lithography process chemicals are preferred. Specifically, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, cyclo Examples include heptanone, 4-methyl-2-pentanol, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, ethyl ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used individually or in combination of two or more.

[0085] Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, and cyclohexanone are preferred. Propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are particularly preferred.

[0086] <Other ingredients> The resist underlayer film formation composition does not produce pinholes or striations, and surfactants can be added to further improve the coatability against surface unevenness.

[0087] Examples of surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkyl allyl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether; polyoxyethylene-polyoxypropylene block copolymers; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; and polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan monopalmitate. Examples include nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters like polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; fluorine-based surfactants such as F-Top EF301, EF303, EF352 (manufactured by Tochem Products Co., Ltd., product name), Megafac F171, F173, R-30 (manufactured by DIC Corporation, product name), Florard FC430, FC431 (manufactured by Sumitomo 3M Co., Ltd., product name), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd., product name); and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). The amount of these surfactants is not particularly limited, but is usually 2.0% by mass or less, preferably 1.0% by mass or less, relative to the total solid content of the resist underlayer film forming composition. These surfactants may be added individually or in combination of two or more types.

[0088] The film components contained in the resist underlayer film forming composition, i.e., the components excluding the solvent, are, for example, 0.01% to 10% by mass of the resist underlayer film forming composition.

[0089] (Underlying resist film) The resist underlayer film of the present invention is a cured product of the resist underlayer film forming composition described above. The resist underlayer film can be manufactured, for example, by applying the aforementioned resist underlayer film forming composition onto a semiconductor substrate and firing it.

[0090] Examples of semiconductor substrates to which the resist underlayer film formation composition is applied include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0091] When using a semiconductor substrate with an inorganic film formed on its surface, the inorganic film is formed, for example, by ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum deposition, or spin coating (spin-on-glass: SOG). Examples of the inorganic film include polysilicon films, silicon oxide films, silicon nitride films, BPSG (Boro-Phospho-Silicate Glass) films, titanium nitride films, titanium oxide nitride films, tungsten films, gallium nitride films, and gallium arsenide films. The inorganic film may be a single layer or a multilayer of two or more layers. In the case of multilayers or more, each layer may be the same type of inorganic film or a different type of inorganic film. There are no particular limitations on the thickness of the inorganic film.

[0092] The resist underlayer film forming composition of the present invention is applied to such a semiconductor substrate by an appropriate coating method such as a spinner or coater. Subsequently, the resist underlayer film is formed by baking using a heating means such as a hot plate. The baking conditions are appropriately selected from a bake temperature of 100°C to 400°C and a bake time of 0.3 minutes to 60 minutes. Preferably, the bake temperature is 120°C to 350°C and the bake time is 0.5 minutes to 30 minutes, and more preferably, the bake temperature is 150°C to 300°C and the bake time is 0.8 minutes to 10 minutes.

[0093] The thickness of the resist underlayer film can be limited to, for example, 1 nm, 2 nm, 3 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 70 nm, 80 nm, 90 nm, and 100 nm at the lower limit, and 10 μm, 8 μm, 5 μm, 3 μm, 2 μm, 1 μm, 900 nm, 800 nm, 700 nm, 600 nm, 500 nm, 400 nm, 300 nm, and 200 nm at the upper limit.

[0094] The method for measuring the thickness of the resist underlayer film in this specification is as follows: • Measurement device name: Ellipso-type film thickness gauge RE-3100 (SCREEN Co., Ltd.) • SWE (Single-Wavelength Ellipsometer) Mode • Arithmetic mean of 8 points (for example, 8 measurements taken at 1cm intervals in the X direction of the wafer)

[0095] (Substrates for semiconductor processing) The semiconductor processing substrate of the present invention comprises a semiconductor substrate and a resist underlayer film of the present invention. Examples of semiconductor substrates include the aforementioned semiconductor substrates. The resist underlayer film is, for example, placed on a semiconductor substrate.

[0096] (Method for manufacturing semiconductor devices, method for forming patterns) The method for manufacturing a semiconductor device of the present invention includes at least the following steps. The process of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film formation composition of the present invention, and • A process of forming a resist film on top of the resist underlayer film.

[0097] The pattern forming method of the present invention includes at least the following steps. • A step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film formation composition of the present invention. • A process of forming a resist film on top of the resist underlayer film. The process of irradiating the resist film with light or an electron beam, then developing the resist film to obtain a resist pattern, and • A process of etching the underlying resist layer using a resist pattern as a mask.

[0098] Typically, a resist film is formed on top of the underlying resist film. The thickness of the resist film is preferably 200 nm or less, more preferably 150 nm or less, even more preferably 100 nm or less, and particularly preferably 80 nm or less. Furthermore, the thickness of the resist film is preferably 10 nm or more, more preferably 20 nm or more, and particularly preferably 30 nm or more.

[0099] The resist formed on the resist underlayer film by, for example, coating and firing using a known method is not particularly limited as long as it responds to the light or electron beam (EB) used for irradiation. Both negative-type and positive-type photoresists can be used. The light or electron beam is not particularly limited, but examples include i-line (365 nm), KrF excimer laser (248 nm), ArF excimer laser (193 nm), EUV (extreme ultraviolet; 13.5 nm), and EB (electron beam). In this specification, resists that respond to EB are also referred to as photoresists. Examples of photoresists include positive-type photoresists consisting of novolac resin and 1,2-naphthoquinone diazide sulfonic acid ester, chemically amplified photoresists consisting of a binder having a group that decomposes with acid to increase the alkali dissolution rate and a photoacid generator, chemically amplified photoresists consisting of a low-molecular-weight compound that decomposes with acid to increase the alkali dissolution rate of the photoresist, an alkali-soluble binder and a photoacid generator, and chemically amplified photoresists consisting of a binder having a group that decomposes with acid to increase the alkali dissolution rate and a low-molecular-weight compound that decomposes with acid to increase the alkali dissolution rate of the photoresist and a photoacid generator, as well as resists containing metal elements. Examples include JSR Corporation's product name V146G, Cypree Corporation's product name APEX-E, Sumitomo Chemical Co., Ltd.'s product name PAR710, and Shin-Etsu Chemical Co., Ltd.'s product names AR2772 and SEPR430. Furthermore, examples include fluorine-containing polymer-based photoresists, such as those described in Proc.SPIE, Vol.3999, 330-334 (2000), Proc.SPIE, Vol.3999, 357-364 (2000), and Proc.SPIE, Vol.3999, 365-374 (2000).

[0100] Also, WO2019 / 188595, WO2019 / 187881, WO2019 / 187803, WO2019 / 167737, WO2019 / 167725, WO2019 / 187445, WO2019 / 167419, WO2019 / 123842, WO2019 / 054282, WO2019 / 058945, WO2019 / 058890, WO2019 / 039290, WO2019 / 044259, WO2019 / 044231, WO2019 / 026549, WO2018 / 193954, WO201 9 / 172054, WO2019 / 021975, WO2018 / 230334, WO2018 / 194123, JP 2018-180525, WO2018 / 190088, JP 2018-070596, JP 2018-028090, JP 2016-153409, JP 2016-130240, JP 2016-108325, JP 2016-047920, JP 2016-035570, JP 2016-035567, JP 2016-035565, JP 2019-101417, JP 2019-117373, JP 2019-052294, JP 2019-008280, JP 2019-008279, JP 2019-003176, JP 2019-003175, JP 2018-197853, JP 2019-191298, JP 2019-061217, JP 2018-045152, JP 2018-022039, JP 2016-090441, JP 2015-10878, JP 2012-168279, JP 2012-022261, JP 2012-022258, JP 2011-043749, JP 2010-18 While so-called resist compositions and metal-containing resist compositions such as those described in JP 1857, JP 2010-128369, WO2018 / 031896, JP 2019-113855, WO2017 / 156388, WO2017 / 066319, JP 2018-41099, WO2016 / 065120, WO2015 / 026482, JP 2016-29498, JP 2011-253185, etc., can be used, they are not limited to these.

[0101] Examples of resist compositions include the following compositions.

[0102] A photosensitive or radiation-sensitive resin composition comprising resin A having repeating units with acid-degradable groups whose polar groups are protected by protective groups that are removed by the action of an acid, and a compound represented by the following general formula (21).

[0103] [ka] In general formula (21), m represents an integer from 1 to 6. R1 and R2 each independently represent a fluorine atom or a perfluoroalkyl group. L1 represents -O-, -S-, -COO-, -SO2-, or -SO3-. L2 represents an alkylene group or single bond which may have substituents. W1 represents a cyclic organic group which may have substituents. M + This represents a cation.

[0104] A metal-containing film-forming composition for extreme ultraviolet or electron beam lithography, comprising a compound having a metal-oxygen covalent bond and a solvent, wherein the metal element constituting the compound belongs to the 3rd to 7th periods of groups 3 to 15 of the periodic table.

[0105] A radiation-sensitive resin composition comprising a polymer having a first structural unit represented by the following formula (31) and a second structural unit represented by the following formula (32) that includes an acid-dissociable group, and an acid generator.

[0106] [ka] (In formula (31), Ar is a group obtained by removing (n+1) hydrogen atoms from an arene with 6 to 20 carbon atoms. 1 R is a hydroxyl group, a sulfanyl group, or a monovalent organic group having 1 to 20 carbon atoms. n is an integer from 0 to 11. If n is 2 or greater, multiple R groups are used. 1 They are the same or different. R 2is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. In formula (32), R 3 is a monovalent group having 1 to 20 carbon atoms and containing the acid dissociable group. Z is a single bond, an oxygen atom or a sulfur atom. R 4 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.)

[0107] A resist composition containing a resin (A1) containing a structural unit having a cyclic carbonate structure, a structural unit represented by the following formula, and a structural unit having an acid labile group, and an acid generator.

[0108]

Chemical formula

[0109] Examples of the resist film include the following.

[0110] A resist film containing a base resin containing a repeating unit represented by the following formula (a1) and / or a repeating unit represented by the following formula (a2), and a repeating unit that generates an acid bonded to the polymer main chain upon exposure.

[0111]

Chemical formula

[0112] Examples of the resist material include the following.

[0113] A resist material containing a polymer having a repeating unit represented by the following formula (b1) or formula (b2).

[0114]

Chemical formula

[0115] A resist material comprising a base resin containing a polymer containing repeating units represented by the following formula (a).

[0116] [ka] (In formula (a), R A R is a hydrogen atom or a methyl group. 1 R is a hydrogen atom or an acid-unstable group. 2 X is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. 1 This is a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms, which may contain a single bond or a phenylene group, or an ester group or a lactone ring. 2 is -O-, -O-CH2-, or -NH-. m is an integer between 1 and 4. u is an integer between 0 and 3. However, m+u is an integer between 1 and 4.

[0117] A resist composition that generates acid upon exposure, and whose solubility in a developer changes due to the action of the acid, It contains a base component (A) whose solubility in the developer changes due to the action of acid, and a fluorine additive component (F) that is degradable in alkaline developer. The fluorine additive component (F) contains a fluororesin component (F1) having a constituent unit (f1) containing a base-dissociable group and a constituent unit (f2) containing a group represented by the following general formula (f2-r-1), wherein the fluorine additive component (F) contains a fluororesin component (F1).

[0118] [ka] [In formula (f2-r-1), Rf 21 Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a hydroxyalkyl group, or a cyano group. n'' is an integer from 0 to 2. * represents a bond.

[0119] The aforementioned constituent unit (f1) includes a constituent unit represented by the following general formula (f1-1) or a constituent unit represented by the following general formula (f1-2).

[0120] [ka] [In formulas (f1-1) and (f1-2), R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. X is a divalent linking group that does not have an acid-dissociable site. A aryl X is a divalent aromatic cyclic group which may have substituents. 01 R is a single bond or a divalent linking group. 2 These are, independently, organic groups that contain a fluorine atom.

[0121] Examples of coatings, coating solutions, and coating compositions include the following:

[0122] A coating comprising a metal oxo-hydroxo network having organic ligands via metal-carbon bonds and / or metal-carboxylate bonds.

[0123] Inorganic oxo / hydroxyl-based composition.

[0124] A coating solution comprising an organic solvent; a first organometallic composition represented by the formula R z SnO (2-(z / 2)-(x / 2)) (OH) x (where 0 < z ≦ 2 and 0 < (z + x) ≦ 4), the formula R’ n SnX 4-n (where n = 1 or 2), or a mixture thereof, wherein R and R’ are independently hydrocarbyl groups having 1 to 31 carbon atoms, and X is a ligand having a hydrolyzable bond to Sn or a combination thereof; and a hydrolyzable metal compound represented by the formula MX’ v (where M is a metal selected from Groups 2 to 16 of the Periodic Table of the Elements, v is a number from 2 to 6, and X’ is a ligand having a hydrolyzable M-X bond or a combination thereof), a coating solution containing a hydrolyzable metal compound.

[0125] A coating solution comprising an organic solvent and a first organometallic compound represented by the formula RSnO (3 / 2-x / 2) (OH) x (where 0 < x < 3), wherein the solution contains about 0.0025 M to about 1.5 M of tin, and R is an alkyl group or cycloalkyl group having 3 to 31 carbon atoms, and the alkyl group or cycloalkyl group is bonded to tin at a secondary or tertiary carbon atom.

[0126] An inorganic pattern-forming precursor aqueous solution comprising a mixture of water, metal oxide cations, polyatomic inorganic anions, and a radiation-sensitive ligand containing peroxide groups.

[0127] Irradiation with light or an electron beam is performed, for example, through a mask (reticle) for forming a predetermined pattern. The exposure amount and the irradiation energy of the electron beam are not particularly limited.

[0128] Post-exposure baking (PEB) may be performed after irradiation with light or electron beam and before development. The baking temperature is not particularly limited, but is preferably 60°C to 150°C, more preferably 70°C to 120°C, and particularly preferably 75°C to 110°C. The baking time is not particularly limited, but is preferably 1 second to 10 minutes, more preferably 10 seconds to 5 minutes, and especially preferably 30 seconds to 3 minutes.

[0129] For developing, for example, an alkaline developer is used. For example, a development temperature of 5°C to 50°C is recommended. Development times can range from, for example, 10 to 300 seconds. As alkaline developers, for example, aqueous solutions of inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-butylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline; and cyclic amines such as pyrrole and piperidine can be used. Furthermore, appropriate amounts of alcohols such as isopropyl alcohol and nonionic surfactants can be added to the aqueous solutions of the above alkalis. Among these, preferred developers are aqueous solutions of quaternary ammonium salts, and more preferably aqueous solutions of tetramethylammonium hydroxide and choline. Furthermore, surfactants can also be added to these developers. Instead of an alkaline developer, a method can be used in which development is performed with an organic solvent such as butyl acetate, and the parts of the photoresist where the alkali dissolution rate has not improved are developed.

[0130] Next, the resist underlayer is etched using the formed resist pattern as a mask. The etching may be dry etching or wet etching, but dry etching is preferred. Examples of etching gases used in dry etching include fluorine-based gases such as CHF3, CF4, C2F6, C3F8, and SF6; chlorine-based gases such as Cl2 and BCl3; oxygen-based gases such as O2, O3, and H2O; reducing gases such as H2, NH3, CO, CO2, CH4, C2H2, C2H4, C2H6, C3H4, C3H6, C3H8, HF, HI, HBr, HCl, NO, NH3, and BCl3; and inert gases such as He, N2, and Ar. These gases may be used individually or in mixtures of two or more. For example, Japanese Patent Publication No. 11-135476 proposes a technique for etching an organic anti-reflective coating using a mixed gas of O2 (oxygen) gas and a halogen-based gas. If the inorganic film is formed on the surface of the semiconductor substrate used, the surface of the inorganic film is exposed. If the inorganic film is not formed on the surface of the semiconductor substrate used, the surface of the semiconductor substrate is exposed. Subsequently, the semiconductor device can be manufactured by processing the semiconductor substrate using a known method (such as dry etching). [Examples]

[0131] The present invention will be described in detail below with reference to examples, but the present invention is not limited in any way to these examples.

[0132] <Measuring molecular weight> The weight-average molecular weights of the polymers shown in the synthesis examples below in this specification are the results of measurements by gel permeation chromatography (hereinafter abbreviated as GPC). A GPC instrument manufactured by Tosoh Corporation was used for the measurements, and the measurement conditions were as follows. • GPC columns: Shodex KF803L, Shodex KF802, Shodex KF801 [registered trademark] (Showa Denko K.K.) Column temperature: 40°C • Solvent: Dimethylformamide (DMF) ·Flow rate: 1.0ml / min • Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0133] <Explanation of Abbreviations> The following are the meanings of the abbreviations for the compounds. • BzMA: Benzyl methacrylate (structure shown below) [ka]

[0134] • HPMA: 2-hydroxypropyl methacrylate (structure shown below) [ka]

[0135] GBLMA: γ-butyrolactone methacrylate (structure shown below) [ka]

[0136] • PGME: Propylene glycol monomethyl ether

[0137] <Synthesis example 1: BzMA / HPMA / GBLMA=25 / 47 / 28(wt%)> In a reaction vessel, 0.68 kg of benzyl methacrylate, 0.66 kg of 2-hydroxypropyl methacrylate, and 0.66 kg of γ-butyrolactone methacrylate were dissolved in 7.0 kg of PGME, and the temperature was raised to 80°C while heating and stirring. 0.02 kg of azobisisobutyronitrile dissolved in 1.0 kg of PGME was added dropwise to the reaction vessel over 1 hour under nitrogen pressure, and the reaction was then allowed to proceed for 24 hours. After the reaction, the mixture was cooled to obtain a polymer solution with a solid content of 20% by mass. The composition ratio of the obtained polymer is BzMA / HPMA / GBLMA = 25 / 47 / 28 (wt%). The obtained polymer had a weight-average molecular weight of 89,000 and a number-average molecular weight of 30,000.

[0138] <Synthesis Example 2: BzMA / HPMA / GBLMA = 25 / 47 / 28 (wt%)> Using BzMA, HPMA, and GBLMA as monomers, polymerization was carried out referring to Reference Example B-3 and Example B-3 of WO 2012 / 053434 pamphlet to obtain a polymer solution with a solid content of 20% by mass. The composition ratio of the obtained polymer is BzMA / HPMA / GBLMA = 25 / 47 / 28 (wt%). The weight average molecular weight of the obtained polymer solution was 10,500, and the number average molecular weight was 5,300.

[0139] <Comparative Example 1> To 38.0 kg of a solution containing 7.7 kg of the polymer obtained in Synthesis Example 1, 1.885 kg of tetramethoxymethyl glycoluril (Nippon Cytec Industries Co., Ltd., trade name: POWDERLINK® 1174) and 0.118 kg of pyridinium-p-toluenesulfonate were mixed. The obtained mixture was dissolved in 440.67 kg of propylene glycol monomethyl ether and 52.83 kg of propylene glycol monomethyl ether acetate to form a solution, and a composition for forming a resist lower layer film was prepared.

[0140] <Example 1> To 15.2 kg of a solution containing 3.0 kg of the polymer obtained in Synthesis Example 2, 0.729 kg of tetramethoxymethyl glycoluril (Nippon Cytec Industries Co., Ltd., trade name: POWDERLINK® 1174) and 0.0455 kg of pyridinium-p-toluenesulfonate were mixed. The obtained mixture was dissolved in 188.25 kg of propylene glycol monomethyl ether and 22.05 kg of propylene glycol monomethyl ether acetate to form a solution, and a composition for forming a resist lower layer film was prepared.

[0141] <DLS Evaluation> Dynamic light scattering measurement was performed on each polymer solution obtained in Synthesis Example 1 and Synthesis Example 2. Dynamic light scattering measurement was performed using a dynamic light scattering photometer DLS-8000Ar (manufactured by Otsuka Electronics Co., Ltd.). Using a He-Ne laser (light wavelength 633 nm) as the incident light, measurement was carried out at a scattering angle of 90°, and the autocorrelation function was obtained. For the obtained autocorrelation function, the average particle size and the polydispersity index were determined by cumulant method analysis using the analysis program attached to the above measurement device. The particle size distribution analysis was performed by the Contin method. The results are shown in Table 1.

[0142] As shown in Table 1, when the polymer solution obtained in Synthesis Example 2 was used, it was confirmed that the average particle size and the polydispersity index were smaller compared to the case of Synthesis Example 1. In FIGS. 1A to 1C, the particle size distributions of Samples 1st, 2nd, and 3rd of Synthesis Example 1 are shown respectively. In FIGS. 2A to 2C, the particle size distributions of Samples 1st, 2nd, and 3rd of Synthesis Example 2 are shown respectively. Note that "f(ls)%" in FIGS. 1A to 1C and FIGS. 2A to 2C represents the scattering intensity distribution. The vertical axis on the right side (the second axis) represents the integrated value of the scattering intensity distribution. As shown in FIGS. 1A to 1C and FIGS. 2A to 2C, it was confirmed that even when comparing the particle size distributions, the distribution of larger particle sizes in Synthesis Example 2 was significantly less.

[0143]

Table 1

[0144] <Etching defect evaluation> The Etching defect evaluation was carried out as follows. Each resist underlayer film forming composition obtained in Comparative Example 1 and Example 1 was applied onto an Etching defect evaluation substrate (Poly Si: 150 nm / SiO2: 80 nm / Si) by a spinner respectively. It was heated at 205 °C for 1 minute on a hot plate to form a resist underlayer film (film thickness 55 nm). This membrane was etched using a Lam Etching apparatus with a chlorine-based mixed gas. Subsequently, a defect inspection device (KLA-Tencor: product name SP1-DLS) was used to determine the number of defects after etching (110 nm up: 81 cm²). 2 The correct answer was confirmed. The results are shown in Table 2.

[0145] As shown in Table 2, it was confirmed that the number of cone defects (number of minute granular etching residues) was lower in the sample of Example 1 compared to the sample of Comparative Example 1.

[0146] [Table 2]

Claims

1. A polymer having a repeating unit (1) represented by the following formula (1) and repeating units (2) other than the repeating unit (1), and a solvent, The average particle size of the polymer in the polymer solution containing the polymer is 20 nm or less. The repeating unit (2) includes a repeating unit (2A-1) represented by the following formula (2A-1) and a repeating unit (2A-2) represented by the following formula (2A-2). A composition for forming a resist underlayer film. 【Chemistry 1】 (In formula (1), R １ R represents a hydrogen atom, a methyl group, or a halogen atom. ２ R represents a trivalent hydrocarbon group with 3 to 6 carbon atoms. ２ The lactone structure containing this compound is a five-membered or six-membered ring. 【Chemistry 2】 (In formula (2A-1), X ２１ R represents -O- or -N(-R)- (where R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). ２１ R represents a hydrogen atom, a methyl group, or a halogen atom. ２２ This represents an alkyl group having 1 to 10 carbon atoms substituted with a hydroxyl group. In formula (2A-2), X ３１ represents -O- or -N(-R)-(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). R ３１ represents a hydrogen atom, a methyl group, or a halogen atom, and R ３２ represents a substituted or unsubstituted aralkyl group, a substituted or unsubstituted carbocyclic aromatic group, or a substituted or unsubstituted heterocyclic aromatic group.)

2. A resist underlayer film, which is a cured product of the resist underlayer film forming composition according to claim 1.

3. Semiconductor substrate and The resist underlayer film according to claim 2, A semiconductor processing substrate equipped with the following features.

4. A step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film formation composition described in claim 1, The steps include forming a resist film on the aforementioned resist underlayer film, A method for manufacturing semiconductor devices, including

5. A step of forming a resist underlayer film on a semiconductor substrate using the resist underlayer film formation composition described in claim 1, The steps include forming a resist film on the aforementioned resist underlayer film, The steps include irradiating the resist film with light or an electron beam, then developing the resist film to obtain a resist pattern, A step of etching the resist underlayer film using the resist pattern as a mask, A pattern formation method, including the following.

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