EUV resist underlayer film forming composition

Abstract

Provided are: a composition for forming a resist underlayer film that enables formation of an intended resist pattern; and a method for producing a resist pattern and a method for producing a semiconductor device, each of which uses said composition for forming a resist underlayer film. Provided is a composition for forming an EUV resist underlayer film, said composition comprising: a compound represented by formula (1); a polymer; and an organic solvent. (In formula (1), Y1 represents a single bond, an oxygen atom, a sulfur atom, a halogen atom, or a C1-10 alkylene group which may be substituted with a C6-40 aryl group, or a sulfonyl group, T1 and T2 each represent a C1-10 alkyl group, R1 and R2 each independently represent a C1-10 alkyl group which is substituted with at least one hydroxy group, and n1 and n2 each independently represent an integer of 0-4).

Description

Technical Field

[0001] The present invention relates to a composition used in a lithography process in semiconductor manufacturing, particularly in state-of-the-art (ArF, EUV, EB, etc.) lithography processes. It also relates to a method for manufacturing a substrate with a resist pattern to which the resist underlayer film is applied, and a method for manufacturing a semiconductor device.

Background Art

[0002] Conventionally, in the manufacture of semiconductor devices, microfabrication by lithography using a resist composition has been carried out. The microfabrication involves forming a thin film of a photoresist composition on a semiconductor substrate such as a silicon wafer, irradiating it with actinic light such as ultraviolet light through a mask pattern on which a device pattern is drawn, developing it, and etching the substrate using the obtained photoresist pattern as a protective film to form fine irregularities corresponding to the pattern on the substrate surface. In recent years, as semiconductor devices have become more highly integrated, the actinic light used has also evolved from the conventionally used i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), and ArF excimer laser (wavelength 193 nm) to the consideration of the practical application of EUV light (wavelength 13.5 nm) or EB (electron beam) for state-of-the-art microfabrication. To control the shape of the resist pattern, a method of forming a resist underlayer film layer between the resist and the semiconductor substrate is widely used.

[0003] Patent Document 1 discloses a resist underlayer film-forming composition containing a sulfur atom. Patent Document 2 discloses a resist underlayer film-forming composition containing a polymer having a structure containing an aromatic ring.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] As characteristics required for a resist underlayer film, for example, there may be mentioned that no intermixing occurs with a resist film formed on the upper layer (being insoluble in a resist solvent), that the dry etching rate is higher than that of the resist film, and that there is little sublimation product during film formation (during baking).

[0006] In the case of lithography involving EUV exposure, a resist underlayer film for EUV exposure is formed to have a thinner film thickness than before. When forming such a thin film, pinholes, aggregation, etc. are likely to occur due to the influence of the substrate surface, the polymer used, etc., and it has been difficult to form a uniform film without defects.

[0007] On the other hand, when forming a resist pattern, in the developing process, a method may be adopted in which an unexposed portion of the resist film is removed using a solvent capable of dissolving the resist film, usually an organic solvent, and the exposed portion of the resist film is left as a resist pattern.

[0008] In such a negative development process, improvement of the adhesion of the resist pattern has been a major issue. Further, suppression of deterioration of LWR (Line Width Roughness, line width roughness, fluctuation of line width (roughness)) during resist pattern formation and formation of a resist pattern having a good rectangular shape, and improvement of resist sensitivity are required. Further, the sublimation product generated during baking of the resist underlayer film has been an issue as it may cause film formation failure or film defects during film formation.

[0009] An object of the present invention is to provide a composition for forming a resist underlayer film capable of forming a desired resist pattern, which solves the above problems, and a resist pattern forming method using the resist underlayer film forming composition. MEANS FOR SOLVING THE PROBLEMS

[0010] This invention encompasses the following: [1] The following formula (1): [ka] (In formula (1), Y 1 This represents a single bond, an oxygen atom, a sulfur atom, a halogen atom, or an alkylene group or sulfonyl group having 1 to 10 carbon atoms which may be substituted with an aryl group having 6 to 40 carbon atoms. T 1 and T 2 This represents an alkyl group with 1 to 10 carbon atoms. R 1 and R 2 Each of these independently represents an alkyl group having 1 to 10 carbon atoms that is substituted with at least one hydroxyl group. n1 and n2 each independently represent integers between 0 and 4. Compounds represented by, polymers and Organic solvents and A composition for forming an EUV resist underlayer film, including the above. [2] Y above 1 The EUV resist underlayer forming composition described in [1], wherein the underlayer is a sulfonyl group. [3] The EUV resist underlayer forming composition according to [1] or [2], wherein the polymer comprises a heterocyclic structure. [4] An EUV resist underlayer forming composition according to any one of [1] to [3], wherein the ends of the polymer are sealed. [5] An EUV resist underlayer forming composition according to any one of [1] to [4], further comprising a crosslinking agent. [6] An EUV resist underlayer forming composition according to any one of [1] to [5], further comprising a crosslinking catalyst. [7] An EUV resist underlayer film characterized by being a fired product of a coated film made from any one of the EUV resist underlayer film forming compositions described in any one of [1] to [6]. [8] A step of applying the EUV resist lower layer film forming composition according to any one of [1] to [6] on a semiconductor substrate and baking to form an EUV resist lower layer film, a step of applying an EUV resist on the EUV resist lower layer film and baking to form an EUV resist film, a step of irradiating the semiconductor substrate coated with the EUV resist lower layer film and the EUV resist with light or an electron beam, and a step of developing and patterning the EUV resist film after exposure. A method for manufacturing a patterned substrate, comprising the steps. [9] A step of forming an EUV resist lower layer film composed of the EUV resist lower layer film forming composition according to any one of [1] to [6] on a semiconductor substrate; A step of forming an EUV resist film on the EUV resist lower layer film; A step of forming an EUV resist pattern by irradiating the EUV resist film with light or an electron beam and then developing; A step of forming a patterned EUV resist lower layer film by etching the EUV resist lower layer film through the formed EUV resist pattern; A step of processing a semiconductor substrate with the patterned EUV resist lower layer film; A method for manufacturing a semiconductor device, characterized by including the above steps.

Effect of the Invention

[0011] By adopting such a configuration, the EUV resist lower layer film forming composition of the present application can achieve an improvement in sensitivity during resist pattern formation and suppression of LWR deterioration. Compared with the prior art, it also has the effect of less sublimation during film formation (firing).

Embodiment for Implementing the Invention

[0012] <EUV Resist Lower Layer Film Forming Composition> The EUV resist lower layer film forming composition of the present application has the following formula (1):

Chemical Formula

[0013] In the description of the above R 1 and R 2 by "substituted with at least one hydroxy group" means that at least one hydrogen atom of the alkyl group having 1 to 10 carbon atoms is substituted with a hydroxy group. It is preferably substituted with 3 or fewer hydroxy groups. It is preferably substituted with 2 or fewer hydroxy groups. It is preferably substituted with a hydroxy group for only one hydrogen atom. For each of R 1 and R 2 it is preferable that the hydrogen atom bonded to the terminal carbon of the compound is substituted with a hydroxy group.

[0014] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

[0015] Examples of the aryl group having 6 to 40 carbon atoms 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.

[0016] The 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, 2,2-dimethyl-n-propyl group, and 1-ethyl-n-propyl group. 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-cyclobutyl 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, and decyl group. Examples of the alkylene group having 1 to 10 carbon atoms include divalent groups derived by removing one hydrogen atom from the alkyl group having 1 to 10 carbon atoms.

[0017] Specific examples of compounds represented by formula (1) include compounds having the structure shown below. [ka] Among these, the above Y 1 It is preferable that the group is a sulfonyl group.

[0018] <polymer> The polymer used in the present invention is not particularly limited as long as it can form an EUV resist underlayer film, but it is preferable that it contains a heterocyclic structure. Examples of such heterocyclic structures include furan, thiophene, pyrrole, imidazole, pyran, pyridine, pyrimidine, pyrazine, pyrrolidine, piperidine, piperazine, morpholine, indole, purine, quinoline, isoquinoline, quinuclidine, chromene, thianthene, phenothiazine, phenoxazine, xanthene, acridine, phenazine, carbazole, triazineone, triazinedione, and triazinetrione.

[0019] The heterocyclic structure is preferably a triazineone, triazinedione, or triazinetrione structure, and most preferably a triazinetrione structure.

[0020] Furthermore, it is preferable that the polymer is a reaction product of a compound containing two epoxy groups and at least one compound selected from a dicarboxylic acid-containing compound, an acidic dianhydride, a compound containing two imino groups, and a compound having two hydroxyl groups.

[0021] Compounds containing the two epoxy groups are shown in formulas (a) to (h) and (v) to (x) below, and compounds selected from dicarboxylic acid-containing compounds, acidic dianhydrides, compounds containing two imino groups, and compounds having two hydroxyl groups are shown in formulas (i) to (k) and (l) to (u) below, but are not limited to these examples. In formula (h), R 0 This represents an alkylene group with 2 to 6 carbon atoms. [ka] [ka] [ka] [ka]

[0022] The polymer used in the present invention may be one of the polymers described in WO2009 / 096340.

[0023] The polymer is given by the following formula (11): [ka] [In the above equation (11), X is the following equation (12), equation (13), or equation (14): [ka] (In equations (12), (13), and (14) above, R 1 ~R 5Each of these independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group, and the phenyl group may be substituted with at least one group selected from the group consisting of alkyl groups having 1 to 6 carbon atoms, halogen atoms, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, and alkylthio groups having 1 to 6 carbon atoms, and R 1 and R 2 , R 3 and R 4 These may be bonded to each other to form a ring with 3 to 6 carbon atoms. ) represents a group represented by A 1 ~A 6 Each of these independently represents a hydrogen atom, a methyl group, or an ethyl group. Q 1 This represents a divalent group containing a disulfide bond, n is the number of repeating unit structures, and can be an integer from 5 to 100. It has a repeating unit structure represented by . Further information relating to this polymer is incorporated herein by reference from the contents of Publication No. WO2009 / 096340.

[0024] The polymer used in the present invention may have a structural unit represented by the following formula (23) as described in WO2020 / 071361. [ka] (In formula (23), A1, A2, A3, A4, A5, and A6 each independently represent a hydrogen atom, a methyl group, or an ethyl group, and Y1 is formula (24), formula (25), formula (26), or formula (27): [ka] ((In formulas (24) to (27), R4 and R5 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group, and the phenyl group may be substituted with at least one group selected from the group consisting of alkyl groups having 1 to 6 carbon atoms, a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a nitro group, a cyano group, a hydroxyl group, and an alkylthio group having 1 to 6 carbon atoms, and R4 and R5 are bonded to each other.) They may together form a ring having 3 to 6 carbon atoms, where R6 represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, a benzyl group, or a phenyl group, and the phenyl group may be substituted with at least one group selected from the group consisting of alkyl groups having 1 to 6 carbon atoms, halogen atoms, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, hydroxyl groups, and alkylthio groups having 1 to 6 carbon atoms), and Q represents formula (28) or formula (29): [ka] (In formulas (28) and (29), Q1 represents an alkylene group, phenylene group, naphthylene group, or anthrylene group having 1 to 10 carbon atoms, and the phenylene group, naphthylene group, and anthrylene group may each be substituted with at least one group selected from the group consisting of alkyl groups having 1 to 6 carbon atoms, halogen atoms, alkoxy groups having 1 to 6 carbon atoms, nitro groups, cyano groups, hydroxyl groups, and alkylthio groups having 1 to 6 carbon atoms, and n4 and n5 each independently represent the number 0 or 1, and Y2 represents formula (24), formula (25), or formula (27)). Further information relating to this polymer is incorporated herein by reference from the contents of Publication No. WO2020 / 071361.

[0025] The ends of the polymer may be sealed with a compound containing an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent.

[0026] The aliphatic ring is preferably a monocyclic or polycyclic aliphatic ring having 3 to 10 carbon atoms. The polycyclic aliphatic ring is preferably a bicyclo or tricyclo ring.

[0027] It is preferable that the aliphatic ring has at least one unsaturated bond.

[0028] Specific examples of carboxyl group-containing compounds that include an aliphatic ring in which the carbon-carbon bond may be interrupted by a heteroatom and may be substituted with a substituent include the compounds listed below. [ka] [ka] [ka]

[0029] Further details regarding compounds containing aliphatic rings in which carbon-carbon bonds may be interrupted by heteroatoms and may be substituted with substituents are as described in PCT / JP2020 / 018436.

[0030] The polymer may have a structure at the end of its polymer chain that is represented by the following formula (31) or (32) as described in Publication No. WO2020 / 071361. [ka] (In formulas (31) and (32) above, X is a divalent organic group, A is an aryl group having 6 to 40 carbon atoms, R1 is a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, R2 and R3 are each independently a hydrogen atom, a halogen atom, an optionally substituted alkyl group having 1 to 10 carbon atoms, or an optionally substituted aryl group having 6 to 40 carbon atoms, n1 and n3 are each independently an integer from 1 to 12, and n2 is an integer from 0 to 11.)

[0031] A compound having the substructure shown in formula (31) above can be represented, for example, by the following formula (1-1). [ka] (In formula (1-1) above, X is a divalent organic group, A is an aryl group having 6 to 40 carbon atoms, R1 is a halogen atom, an alkyl group having 1 to 40 carbon atoms, or an alkoxy group having 1 to 40 carbon atoms, n1 is an integer from 1 to 12, and n2 is an integer from 0 to 11.)

[0032] Specific examples of compounds represented by the above formula (1-1) are as follows: [ka] [ka] [ka] [ka] [ka] [ka]

[0033] A compound having the substructure shown in formula (32) above can be represented, for example, by the following formula (2-1). [ka] (In formula (2-1) above, X is a divalent organic group, A is an aryl group having 6 to 40 carbon atoms, R2 and R3 are each independently a hydrogen atom, an optionally substituted alkyl group having 1 to 10 carbon atoms, an optionally substituted aryl group having 6 to 40 carbon atoms, or a halogen atom, and n3 is an integer from 1 to 12.)

[0034] Specific examples of compounds represented by the above formula (2-1) are as follows: [ka]

[0035] Further information relating to this terminal structure is incorporated herein by reference from the contents of Publication No. WO2020 / 071361.

[0036] The end of the polymer is defined by the following formula (41) or formula (42): [ka] (In formulas (41) and (42), R1 represents an alkyl group having 1 to 6 carbon atoms which may have substituents, a phenyl group, a pyridyl group, a halogen group, or a hydroxyl group; R2 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have substituents, a hydroxyl group, a halogen group, or an ester group represented by -C(=O)OX; X represents an alkyl group having 1 to 6 carbon atoms which may have substituents; R3 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have substituents, a hydroxyl group, or a halogen group; R4 represents a direct bond or a divalent organic group having 1 to 8 carbon atoms; R5 represents a divalent organic group having 1 to 8 carbon atoms; A represents an aromatic ring or an aromatic heterocycle; t represents 0 or 1; and u represents 1 or 2.)

[0037] For further details relating to formulas (41) and (42) above, the disclosures in WO2015 / 163195 are incorporated herein by reference.

[0038] The reaction product terminal structures of compound (A) and compound (B), represented by formulas (41) and (42) above, can be produced by the reaction of the polymer with the compound represented by the following formula (41a) and / or the compound represented by the following formula (42a). [ka] (The meanings of the symbols in equations (41a) and (42a) above are as explained in equations (41) and (42) above.)

[0039] Examples of compounds represented by formula (41a) include those represented by the following formula. [ka] [ka] [ka] [ka] [ka]

[0040] Examples of compounds represented by formula (42a) include those represented by the following formula. [ka]

[0041] <Organic solvents> Examples of organic solvents included in the EUV resist underlayer film forming composition of the present invention include 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, and cyclopene. Examples include tanone, cyclohexanone, cycloheptanone, 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.

[0042] 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.

[0043] <Crosslinking agent> Examples of crosslinking agents that may be included as optional components in the EUV resist underlayer film forming composition of the present invention 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.

[0044] Furthermore, the crosslinking agent of this application may be a nitrogen-containing compound having 2 to 6 substituents represented by the following formula (51) that bond to a nitrogen atom in one molecule, as described in WO2017 / 187969. [ka] (In formula (51), R1 represents a methyl group or an ethyl group.)

[0045] A nitrogen-containing compound having 2 to 6 substituents represented by formula (51) in one molecule may be a glycoluryl derivative represented by the following formula (1A). [ka] (In formula (1A), 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.)

[0046] Examples of glycoluryl derivatives represented by formula (1A) include the compounds represented by the following formulas (1A-1) to (1A-6). [ka]

[0047] The compound represented by formula (1A) is obtained by reacting a nitrogen-containing compound having 2 to 6 substituents represented by formula (52) in one molecule that bond to a nitrogen atom with at least one compound represented by formula (53) below to produce a nitrogen-containing compound having 2 to 6 substituents represented by formula (51) in one molecule. [ka] (In formulas (52) and (53), R1 represents a methyl group or an ethyl group, and R4 represents an alkyl group having 1 to 4 carbon atoms.)

[0048] The glycoluryl derivative represented by formula (1A) is obtained by reacting the glycoluryl derivative represented by formula (2A) with at least one compound represented by formula (53).

[0049] A nitrogen-containing compound having 2 to 6 substituents represented by formula (52) in one molecule is, for example, a glycoluryl derivative represented by the following formula (2A). [ka] (In formula (2A), 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.)

[0050] Examples of glycoluryl derivatives represented by formula (2A) include the compounds represented by formulas (2A-1) to (2A-4) below. Furthermore, examples of compounds represented by formula (53) include the compounds represented by formulas (3-1) and (3-2) below. [ka] [ka]

[0051] Further details regarding nitrogen-containing compounds having 2 to 6 substituents represented by the following formula (51) bonded to nitrogen atoms in a single molecule are as described in Publication WO2017 / 187969.

[0052] When the above-mentioned crosslinking agent is used, the content of the crosslinking agent is, for example, 1% to 50% by mass relative to the polymer, preferably 5% to 30% by mass.

[0053] <Crosslinking catalyst (curing catalyst)> Examples of crosslinking catalysts (curing catalysts) that may be included as optional components in the EUV resist underlayer film forming composition of the present invention include sulfonic acid compounds and carboxylic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium-p-toluenesulfonate (pyridinium-p-toluenesulfonic 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.

[0054] When the above-mentioned crosslinking catalyst is used, the content of the crosslinking catalyst is, for example, 0.1% to 50% by mass, preferably 1% to 30% by mass, relative to the crosslinking agent.

[0055] <Other ingredients> In the resist underlayer film-forming composition of the present invention, in order to prevent the occurrence of pinholes, striations, etc., and further improve the coating property with respect to surface unevenness, a surfactant can be further added. Examples of the surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether; polyoxyethylene alkyl aryl ethers such as polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether; polyoxyethylene - polyoxypropylene block copolymers; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate; polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, etc., nonionic surfactants; Fluorine-based surfactants such as F-Top EF301, EF303, EF352 (trade names, manufactured by Tocem Products Co., Ltd.), Megafac F171, F173, R-30 (trade names, manufactured by Dainippon Ink and Chemicals, Inc.), Florard FC430, FC431 (trade names, manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (trade names, manufactured by Asahi Glass Co., Ltd.), etc.; organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc. The blending amount of these surfactants is usually 2.0% by mass or less, preferably 1.0% by mass or less, based on the total solid content of the resist underlayer film-forming composition of the present invention. These surfactants may be added alone or in combination of two or more kinds.

[0056] <EUV resist underlayer film> The EUV resist underlayer film according to the present invention can be manufactured by applying the above-described EUV resist underlayer film forming composition onto a semiconductor substrate and firing it.

[0057] Examples of semiconductor substrates to which the resist underlayer film forming composition of the present invention is coated include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0058] When using a semiconductor substrate with an inorganic film formed on its surface, the inorganic film is formed by, for example, 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.

[0059] 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.

[0060] The thickness of the EUV resist underlayer film formed can be, for example, 0.001 μm (1 nm) to 10 μm, 0.002 μm (2 nm) to 1 μm, 0.005 μm (5 nm) to 0.5 μm (500 nm), 0.001 μm (1 nm) to 0.05 μm (50 nm), 0.002 μm (2 nm) to 0.05 μm (50 nm), or 0.003 μm (1 nm). The acceptable thickness ranges are: m)~0.05μm (50nm), 0.004μm (4nm)~0.05μm (50nm), 0.005μm (5nm)~0.05μm (50nm), 0.003μm (3nm)~0.03μm (30nm), 0.003μm (3nm)~0.02μm (20nm), and 0.005μm (5nm)~0.02μm (20nm). If the baking temperature is lower than the above range, crosslinking will be insufficient. On the other hand, if the baking temperature is higher than the above range, the resist underlayer film may decompose due to heat.

[0061] <Manufacturing method for patterned substrates, manufacturing method for semiconductor devices> The manufacturing method for patterned substrates follows the steps outlined below. Typically, a photoresist layer is formed on top of an EUV resist underlayer. The photoresist formed by coating and firing on top of the EUV resist underlayer using a known method is not particularly limited as long as it is sensitive to the light used for exposure. Both negative and positive photoresists can be used. Examples include positive photoresists composed of novolac resin and 1,2-naphthoquinone diazide sulfonic acid ester, chemically amplified photoresists composed of a binder having a group that decomposes with acid to increase the alkali dissolution rate and a photoacid generator, chemically amplified photoresists composed 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 composed 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 V146G (manufactured by JSR Corporation), APEX-E (manufactured by Cyprey Corporation), PAR710 (manufactured by Sumitomo Chemical Co., Ltd.), and AR2772 and SEPR430 (manufactured by Shin-Etsu Chemical Co., Ltd.). Additionally, examples include fluorine-containing polymer 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).

[0062] 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.

[0063] Examples of resist compositions include the following: A photosensitive or radiation-sensitive resin composition comprising resin A having repeating units with acid-degradable groups whose polar groups are protected by protecting groups that are removed by the action of an acid, and a compound represented by general formula (61). [ka] In general formula (61), 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.

[0064] 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.

[0065] A radiation-sensitive resin composition comprising a polymer having a first structural unit represented by the following formula (71) and a second structural unit represented by the following formula (72) that includes an acid-dissociable group, and an acid generator. [ka] (In formula (71), 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 2 These are a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0066] In formula (72), R3 This is a monovalent group having 1 to 20 carbon atoms that contains the above-mentioned acid-dissociable group. Z is a single bond, an oxygen atom, or a sulfur atom. R 4 (This is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.)

[0067] A resist composition containing a resin (A1) comprising structural units having a cyclic carbonate ester structure, structural units represented by formula (II), and structural units having acid-unstable groups, and an acid generator. [ka] [In formula (II), R 2 X represents an alkyl group having 1 to 6 carbon atoms, a hydrogen atom, or a halogen atom, which may have a halogen atom. 1 These are single bonds, -CO-O-*, or -CO-NR 4 -* represents a bond with -Ar, and R 4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, which may have one or more groups selected from the group consisting of hydroxyl groups and carboxyl groups.

[0068] 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 resist composition is characterized in that 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). [ka] [In formula (f2-r-1), Rf 21Each 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.

[0069] The aforementioned constituent unit (f1) may include a constituent unit represented by the following general formula (f1-1) or a constituent unit represented by the following general formula (f1-2). [ka] [In formulas (f1-1) and (f1-2), R is independently a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. 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.

[0070] Examples of metal-containing resist compositions include coatings containing a metal oxo-hydroxo network with organic ligands via metal-carbon bonds and / or metal-carboxylate bonds, and inorganic oxo / hydroxo-based compositions.

[0071] Examples of resist materials include the following: A resist material comprising a polymer having repeating units represented by the following formula (a1) or (a2). [ka] (In equations (a1) and (a2), R A X is a hydrogen atom or a methyl group. 1 X is a single bond or an ester group. 2X is a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms or an arylene group having 6 to 10 carbon atoms, and a portion of the methylene groups constituting the alkylene group may be substituted with an ether group, an ester group, or a lactone ring-containing group, and X 2 At least one hydrogen atom in X is replaced by a bromine atom. 3 Rf is a single bond, an ether group, an ester group, or a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms, and some of the methylene groups constituting the alkylene group may be substituted with an ether group or an ester group. 1 ~Rf 4 Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They may combine to form a carbonyl group. 1 ~R 5 Each of these is independently a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, a linear, branched, or cyclic alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an aryloxyalkyl group having 7 to 12 carbon atoms, and some or all of the hydrogen atoms of these groups may be substituted with a hydroxyl group, a carboxyl group, a halogen atom, an oxo group, a cyano group, an amide group, a nitro group, a sultone group, a sulfone group, or a sulfonium salt-containing group, and some of the methylene groups constituting these groups may be substituted with an ether group, an ester group, a carbonyl group, a carbonate group, or a sulfonic acid ester group. 1 and R 2 These may combine to form a ring with the sulfur atom to which they are bonded.

[0072] A resist material comprising a base resin containing a polymer containing repeating units represented by the following formula (81). [ka] (In formula (81), R Ais a hydrogen atom or a methyl group. R 1 is a hydrogen atom or an acid-labile group. R 2 is a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. X 1 is a single bond or a phenylene group, or a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms which may contain an ester group or a lactone ring. X 2 is -O-, -O-CH2- or -NH-. m is an integer of 1 to 4. n is an integer of 0 to 3.)

[0073] Examples of the resist film include the following. A resist film containing a base resin containing a repeating unit represented by the following formula (91) and / or a repeating unit represented by the following formula (92), and a repeating unit that generates an acid bonded to the polymer main chain upon exposure.

Chemical formula

[0074] Examples of the coating solution include the following. A coating solution, an organic solvent; a first organometallic composition, of the formula R z SnO (2-(z / 2)-(x / 2)) (OH) x (where 0 < z ≦ 2 and 0 < (z + x) ≦ 4), of the formula R’[[ID=$$]] n SnX4-n represented by (where n = 1 or 2), or a mixture thereof, where 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, a first organometallic composition; 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.

[0075] an organic solvent and a first organometallic compound represented by the formula RSnO (3 / 2-x / 2) (OH) x (where 0 < x < 3), a coating solution containing about 0.0025 M to about 1.5 M of tin in the solution, 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.

[0076] an inorganic pattern-forming precursor aqueous solution comprising a mixture of water, a metal oxide cation, a polyatomic inorganic anion, and a radiation-sensitive ligand containing a peroxide group. And the like.

[0077] Exposure is performed through a mask (reticle) to form a predetermined pattern, and for example, i-ray, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet), or EB (electron beam) are used, but the resist underlayer film forming composition of this application is preferably applied for EUV (extreme ultraviolet) exposure. For development, an alkaline developer is used, and the development temperature is appropriately selected from 5°C to 50°C and the development time from 10 seconds to 300 seconds. As the alkaline developer, aqueous solutions of alkalis such as 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, an appropriate amount of alcohol such as isopropyl alcohol and a nonionic surfactant can be added to the aqueous solution of the above alkalis. Among these, preferred developers are quaternary ammonium salts, and more preferably 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 whose alkali dissolution rate has not improved are developed. Through the above process, a substrate with the resist patterned can be manufactured.

[0078] Next, the resist underlayer film is dry-etched using the formed resist pattern as a mask. At this time, 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. After that, the substrate is processed by a known method (such as dry etching) to manufacture a semiconductor device. [Examples]

[0079] The present invention will now be specifically described with reference to examples, but the present invention is not limited to these examples.

[0080] The weight-average molecular weights of the polymers shown in Synthesis Example 1 and Comparative Synthesis Example 1 in this specification were obtained by measurement using gel permeation chromatography (hereinafter abbreviated as GPC). A GPC instrument manufactured by Tosoh Corporation was used for the measurement, and the measurement conditions were as follows.

[0081] GPC columns: Shodex KF803L, Shodex KF802, Shodex KF801 [registered trademark] (Showa Denko K.K.) Column temperature: 40℃ Solvent: Tetrahydrofuran (THF)

[0082] Flow rate: 1.0ml / min Standard sample: Polystyrene (manufactured by Tosoh Corporation)

[0083] <Synthesis Example 1> 3.00 g of monoallyl diglycidyl isocyanuric acid (manufactured by Shikoku Chemicals, Inc.), 1.91 g of 3,3'-dithiodipropionic acid (manufactured by Sakai Chemicals, Inc., trade name: DTDPA), 0.57 g of adamantanecarboxylic acid (manufactured by Tokyo Chemical Industries, Inc.), and 0.14 g of tetrabutylphosphonium bromide (manufactured by ACROSS) were added to 6.87 g of propylene glycol monomethyl ether and dissolved. After purging the reaction vessel with nitrogen, the reaction was carried out at 105°C for 8 hours to obtain a polymer solution. The polymer solution did not become cloudy or otherwise discolored even when cooled to room temperature, and its solubility in propylene glycol monomethyl ether was good. GPC analysis revealed that the polymer in the obtained solution had a weight-average molecular weight of 5,000 on a standard polystyrene basis. The polymer obtained in this synthesis example has structural units represented by the following formulas (1a), (2a), and (3a). [ka]

[0084] <Example 1> To 2.60 g of the polymer solution containing 0.45 g of the polymer obtained in Synthesis Example 1 above, 0.50 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries, Ltd.), 0.10 g of pyridinium p-phenolsulfonate salt (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.20 g of bis[4-(2-hydroxyethoxy)phenyl]sulfone (1b) (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed. Then, 26.30 g of propylene glycol monomethyl ether and 2.99 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition. [ka]

[0085] <Example 2> To 0.26 g of the polymer solution containing 0.045 g of the polymer obtained in Synthesis Example 1 above, 0.05 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.01 g of pyridinium p-phenolsulfonate salt (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.02 g of bis[4-(2-hydroxyethoxy)phenyl]sulfone (1b) (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed, and 26.30 g of propylene glycol monomethyl ether and 2.99 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0086] <Comparative Example 1> To 2.60 g of the polymer solution containing 0.45 g of the polymer obtained in Synthesis Example 1 above, 0.50 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.) and 0.10 g of pyridinium p-phenolsulfonate salt (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed, and 26.30 g of propylene glycol monomethyl ether and 2.99 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0087] <Comparative Example 2> To 0.26 g of the polymer solution containing 0.045 g of the polymer obtained in Synthesis Example 1 above, 0.05 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries, Ltd.) and 0.01 g of pyridinium p-phenolsulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed, and 26.30 g of propylene glycol monomethyl ether and 2.99 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0088] <Comparative Example 3> To 2.60 g of the polymer solution containing 0.45 g of the polymer obtained in Synthesis Example 1 above, 0.50 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.10 g of pyridinium p-phenolsulfonate salt (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.20 g of bisphenol S(2b) (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed. Then, 26.30 g of propylene glycol monomethyl ether and 2.99 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition. [ka]

[0089] <Comparative Example 4> To 0.26 g of the polymer solution containing 0.045 g of the polymer obtained in Synthesis Example 1 above, 0.05 g of tetramethoxymethyl glycoluryl (manufactured by Nippon Scitec Industries Co., Ltd.), 0.01 g of pyridinium p-phenolsulfonate salt (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.02 g of bisphenol S(2b) (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed. Then, 26.30 g of propylene glycol monomethyl ether and 2.99 g of propylene glycol monomethyl ether acetate were added and dissolved. The mixture was then filtered using a polyethylene microfilter with a pore size of 0.05 μm to obtain a lithography resist underlayer film forming composition.

[0090] [Elution test into photoresist solvent] The resist underlayer film forming compositions of Example 1, Example 2, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4 were each coated onto a silicon wafer, which is a semiconductor substrate, using a spinner. The silicon wafer was then placed on a hot plate and baked at 205°C for 1 minute to form a resist underlayer film (thickness 5 nm). These resist underlayer films were immersed in ethyl lactate and propylene glycol monomethyl ether, which are solvents used in photoresists, and it was confirmed that they were insoluble in these solvents.

[0091] [Measurement of sublimation volume] The amount of sublimation was measured using the sublimation quantity measuring device described in International Publication No. 2007 / 111147. First, the resist underlayer film forming compositions prepared in Example 1, Comparative Example 1, and Comparative Example 3 were applied to a 4-inch diameter silicon wafer substrate using a spin coater to a film thickness of 50 nm. The wafer coated with the resist underlayer film was placed in the sublimation quantity measuring device, which has an integrated hot plate, and baked for 120 seconds. The sublimated material was collected by a QCM (Quartz Crystal Microbalance) sensor, i.e., a quartz crystal oscillator with electrodes formed on it. The QCM sensor can measure minute mass changes by utilizing the property that when sublimated material adheres to the surface (electrode) of the quartz crystal oscillator, the frequency of the quartz crystal oscillator changes (decreases) according to the mass of the sublimated material. The detailed measurement procedure is as follows: The hot plate of the sublimation quantity measuring device was heated to the measurement temperature shown in Table 1, and the pump flow rate was set to 1 m³. 3The timer was set to / s, and the device was left undisturbed for the first 60 seconds to stabilize. Immediately thereafter, a wafer coated with a resist underlayer was quickly placed onto the hot plate through the slide opening, and sublimation was collected from 60 seconds to 180 seconds (120 seconds). The flow attachment (detection part) connecting the QCM sensor and the collection funnel of the sublimation volume measuring device was used without a nozzle. Therefore, the airflow flowed in without restriction from the flow path (hole diameter: 32 mm) of the chamber unit, which was 30 mm away from the sensor (quartz crystal oscillator). The QCM sensor used a material mainly composed of silicon and aluminum (AlSi) as electrodes, with a quartz crystal oscillator diameter (sensor diameter) of 14 mm, an electrode diameter on the surface of the quartz crystal oscillator of 5 mm, and a resonant frequency of 9 MHz. The obtained frequency changes were converted to grams from the intrinsic values ​​of the quartz crystal oscillator used for measurement, and the relationship between the amount of sublimation and the firing temperature of one wafer coated with a resist underlayer was clarified. Note that the first 60 seconds were left unattended (without the wafer set) to stabilize the apparatus, and the measurements taken from 60 seconds after the wafer was placed on the hot plate to 180 seconds represent the measured amount of sublimation on the wafer. The amount of sublimation of the resist underlayer quantified from the apparatus is shown in Table 1 below as the sublimation amount ratio. The sublimation amount ratio is expressed as a value normalized by setting the amount of sublimation generated from the resist underlayer in Comparative Example 3 to 1.00. From these results, it was shown that Example 1 (containing the compound represented by formula (1b)) can significantly suppress sublimation during firing compared to Comparative Example 3 (containing the compound represented by formula (2b)). [Table 1]

[0092] [Formation of resist patterns using electron beam lithography equipment] The resist underlayer-forming compositions of Example 2, Comparative Example 2, and Comparative Example 4 were applied to silicon wafers using a spinner. The silicon wafers were baked on a hot plate at 205°C for 60 seconds to obtain a resist underlayer with a thickness of 5 nm. An EUV positive-type resist solution (containing methacrylic polymer) was spin-coated onto the resist underlayer and heated at 130°C for 60 seconds to form an EUV resist film. The resist film was exposed to electron beam lithography (ELS-G130) under predetermined conditions. After exposure, it was baked at 100°C for 60 seconds (PEB), cooled to room temperature on a cooling plate, developed with alkaline developer (2.38% TMAH), and then a resist pattern with 25 nm lines / 50 nm pitch was formed. A scanning electron microscope (Hitachi High-Technologies Corporation, CG4100) was used to measure the length of the resist pattern. In forming the above resist pattern, the exposure amount used to form a 25nm line / 50nm pitch (line and space (L / S=1 / 1)) was considered the optimal exposure amount.

[0093] The photoresist patterns obtained in this manner were observed and evaluated from above. Table 2 shows the exposure amount and LWR required for the resist pattern to form a 25 nm line. In the results of Example 2, a decrease in the exposure amount required for 25 nm pattern formation (improved sensitivity) and an improvement in LWR were confirmed compared to Comparative Examples 2 and 4. From these results, it was shown that a resist underlayer film containing the compound represented by formula (1b) exhibits the above effect compared to a resist underlayer film containing the compound represented by formula (2b). This is thought to be because the compound represented by formula (1b) remains in the film at a higher rate than the compound represented by formula (2b) by bonding with the polymer contained in the resist underlayer film. [Table 2] [Industrial applicability]

[0094] The resist underlayer film forming composition according to the present invention provides a composition for forming a resist underlayer film capable of forming a desired resist pattern, a method for manufacturing a substrate with a resist pattern using the resist underlayer film forming composition, and a method for manufacturing a semiconductor device.

Claims

1. The following formula (1): 【Chemistry 52】 (In formula (1), Y １ It is a sulfonyl group, T １ and T ２ This represents an alkyl group having 1 to 10 carbon atoms. R １ and R ２ Each of these independently represents an alkyl group having 1 to 10 carbon atoms that is substituted with at least one hydroxyl group. (n1 and n2 each independently represent integers between 0 and 4.) Compounds represented by, polymers and Organic solvents and A composition for forming an EUV resist underlayer, comprising [the specified element].

2. The EUV resist underlayer film forming composition according to claim 1, wherein the polymer comprises a heterocyclic structure.

3. The EUV resist underlayer film forming composition according to claim 1 or 2, wherein the ends of the polymer are sealed.

4. The EUV resist underlayer film forming composition according to any one of claims 1 to 3, further comprising a crosslinking agent.

5. The EUV resist underlayer film forming composition according to any one of claims 1 to 4, further comprising a crosslinking catalyst.

6. An EUV resist underlayer film characterized by being a fired product of a coated film made from the EUV resist underlayer film forming composition according to any one of Claims 1 to 5.

7. A method for manufacturing a patterned substrate, comprising the steps of: applying an EUV resist underlayer forming composition according to any one of claims 1 to 5 onto a semiconductor substrate and baking to form an EUV resist underlayer; applying an EUV resist onto the EUV resist underlayer and baking to form an EUV resist film; irradiating the semiconductor substrate coated with the EUV resist underlayer and the EUV resist with light or an electron beam; and developing and patterning the EUV resist film after exposure.

8. A step of forming an EUV resist underlayer film on a semiconductor substrate, comprising the EUV resist underlayer film forming composition according to any one of Claims 1 to 5, A step of forming an EUV resist film on the aforementioned EUV resist underlayer film, A process of forming an EUV resist pattern by irradiating an EUV resist film with light or an electron beam and then developing it, A step of forming a patterned EUV resist underlayer film by etching the EUV resist underlayer film through the formed EUV resist pattern, A process of processing a semiconductor substrate with the patterned EUV resist underlayer film, A method for manufacturing a semiconductor device, characterized by including the following:

Images