Underlayer membrane material for self-assembled materials

Abstract

A composition for forming an underlayer film, which is used for forming an underlayer film of a self-assembled film, and which contains a polymer having a unit structure (A) that has an alicyclic hydrocarbon group having a reactive group.

Description

Technical Field

[0001] The present invention relates to a composition for forming a lower layer film and a lower layer film used to form a self-assembled film, and a method for manufacturing a semiconductor device using the same. Background Technology

[0002] In recent years, with the further miniaturization of large-scale integrated circuits (LSI), there has been a demand for technologies that can process finer structures. To address this demand, attempts have been made to form finer patterns using phase-separated structures formed by the self-assembly of block copolymers obtained by bonding mutually incompatible polymers. For example, a pattern formation method has been proposed as follows: a lower layer film forming composition is coated on a substrate; a lower layer film formed from the composition is formed; a self-assembled film containing block copolymers of two or more polymers is formed on the surface of the lower layer film; phase separation of the block copolymers in the self-assembled film is performed; and the phase of at least one polymer constituting the block copolymer is selectively removed, thereby forming a pattern.

[0003] Patent Document 1 discloses a composition for forming the lower layer of a self-assembled membrane, which comprises a polymer having a unit structure of more than 20 mol% of substituted aromatic vinyl compounds such as styrene, vinylnaphthalene, acenaphthene, and vinylcarbazole relative to the total unit structure of the polymer, and having a unit structure of more than 1 mol% of polycyclic aromatic vinyl compounds relative to the total unit structure of the aromatic vinyl compounds.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2014 / 097993 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] As the lower layer of the self-assembled membrane, in order to form the fine patterns using the self-assembled membrane, a substrate membrane that is easier to orient in the desired vertical pattern (that can form a vertical orientation in the self-assembled membrane) is required.

[0009] This invention provides a composition for forming a lower layer film that can form a substrate layer. This substrate layer, as a lower layer film of a self-assembled film, has good film-forming properties and can form a vertical orientation in the self-assembled film. Furthermore, this invention provides a lower layer film using this composition for forming a lower layer film, and a method for manufacturing a semiconductor device using this lower layer film.

[0010] Methods for solving problems

[0011] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that the above-mentioned problems could be solved, and completed the present invention with the following main points.

[0012] That is, the present invention includes the following solutions.

[0013] [1] A composition for forming a lower layer film, which is a composition for forming a lower layer film for forming a self-assembled film. It contains polymers, The polymer described above has a unit structure (A), which has an alicyclic hydrocarbon group having a reactive group.

[0014] [2] According to the composition for forming the lower layer film described in [1], the above-mentioned unit structure (A) is the unit structure shown in the following formula (A-1).

[0015]

[0016] (In equation (A-1), R) 1 Represents a hydrogen atom or a methyl group. X 1 Indicates a single bond, ester group, or amide group. Y 1 Indicates a single bond or an alkylene group having 1 to 6 carbon atoms. Cy represents an alicyclic hydrocarbon group with a reactive group.

[0017] [3] According to the composition for forming the lower film as described in [1] or [2], the polymer also has a unit structure as shown in the following formula (B-1).

[0018]

[0019] (In equation (B-1), R) 11 This indicates a hydrogen atom or a methyl group. Ar 11 (This indicates an aromatic group that can be substituted.)

[0020] [4] According to the composition for forming the lower layer film described in [3], in the above formula (B-1), Ar 11 This indicates naphthalene, anthracene, phenanthrene, pyrene, benzo[9,10]phenanthrene, etc., which can be substituted. , tetraphenyl, biphenylene, fluorene or carbazole, or benzene having one or more substituents having 1 to 6 carbon atoms as hydrocarbon groups.

[0021] [5] The composition for forming a lower film according to any one of [1] to [4] further comprises a unit structure (C) having a monocyclic aromatic structure.

[0022] [6] According to the composition for forming the lower layer film described in [5], the above-mentioned unit structure (C) is the unit structure shown in the following formula (C-1).

[0023]

[0024] (In equation (C-1), R) 21 Represents a hydrogen atom or a methyl group. X 21 Indicates an ester group or an amide group. Y 21 Indicates a single bond or an alkylene group having 1 to 6 carbon atoms. Z 21 Indicates a single bond or an ether group. Ar 21 Indicates that benzene, naphthalene, or anthracene can be substituted. R 22 This represents a halogen atom or an organogroup with 1 to 10 carbon atoms that can be substituted. n represents an integer from 0 to 5. In R... 22 When there are two or more R's 22 They can be the same or different.

[0025] [7] The composition for forming a lower film according to any one of [1] to [6] further comprises a unit structure (D) having a hydrocarbon group having a reactive group (but excluding alicyclic hydrocarbon groups).

[0026] [8] According to the composition for forming the lower layer film described in [7], the above-mentioned unit structure (D) is the unit structure shown in the following formula (D-1).

[0027]

[0028] (In equation (D-1), R) 31 Represents a hydrogen atom or a methyl group. X 31 Indicates an ester group or an amide group. R 32 This refers to a hydrocarbon group with 1 to 12 carbon atoms that has a reactive group (excluding alicyclic hydrocarbon groups).

[0029] [9] In any one of [1] to [8], the molar ratio of the above-mentioned unit structure (A) to the total unit structure of the above-mentioned polymer is less than 60 moles.

[0030]

[10] In any one of [3] to [9], the molar ratio of the above-mentioned unit structure (B-1) to the total unit structure of the above-mentioned polymer is 45 mol% to 80 mol%.

[0031]

[11] The composition for forming a lower film according to any one of [1] to

[10] further comprises a crosslinking agent, wherein the content of the crosslinking agent is 20% to 50% by mass of the polymer.

[0032]

[12] The composition for forming a lower layer film according to any one of [1] to

[11] , wherein the self-assembled film is a film comprising a block copolymer.

[0033]

[13] The composition for forming a lower layer film according to any one of [1] to

[13] is a composition for forming a lower layer film, wherein the lower layer film is used as a lower layer film of the self-assembled film after being used as a lower layer film of the photoresist film and an electron beam photoresist film in photolithography using the self-assembled film.

[0034]

[14] A lower layer film is a sintered product of a coated film of any one of the lower layer film forming compositions described in any one of [1] to

[13] .

[0035]

[15] According to the lower membrane described in

[14] , the thickness of the lower membrane is less than 10 nm.

[0036]

[16] A method for manufacturing a semiconductor device, comprising the following steps: The process of forming a lower layer film on a semiconductor substrate using any one of the lower layer film forming compositions described in [1] to

[13] ; and The process of forming a self-assembled membrane on the aforementioned lower membrane.

[0037]

[17] According to the semiconductor device manufacturing method described in

[16] , in the process of forming the self-assembled film, the self-assembled film is formed on the patterned lower film. The method for manufacturing the semiconductor device further includes the following steps: The process of forming any one of photoresist film and electron beam resist film on the aforementioned lower layer film; The process of subjecting the above-mentioned resist film to light or electron beam irradiation, followed by developing the above-mentioned resist film to obtain a resist pattern; and The process of using the above-mentioned resist pattern as a mask to etch the above-mentioned lower film to form the above-mentioned patterned lower film.

[0038]

[18] The semiconductor device manufacturing method according to

[17] further includes a step of forming a brush layer in the gaps of the patterned lower layer between the step of forming the patterned lower layer and the step of forming the self-assembled film.

[0039]

[19] In the method for manufacturing a semiconductor element according to any one of

[16] to

[18] , the self-assembled film is a film containing a block copolymer.

[0040]

[20] The method for manufacturing a semiconductor element according to any one of

[17] to

[19] further includes, after the step of forming the patterned lower layer film, a step of removing the resist pattern.

[0041] The effects of the invention

[0042] According to the present invention, a composition for forming a lower layer film can be provided, which has good film-forming properties as a lower layer film for self-assembly and is capable of forming a self-assembly film with good vertical alignment. Furthermore, the present invention can provide a lower layer film using the composition for forming the lower layer film, and a method for manufacturing a semiconductor device using the lower layer film. Attached Figure Description

[0043] Figure 1A A cross-sectional schematic diagram (1) is provided for illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0044] Figure 1B A cross-sectional schematic diagram (2) is provided for illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0045] Figure 1C This is a cross-sectional schematic diagram (3) illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0046] Figure 1D A cross-sectional schematic diagram (4) illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0047] Figure 1E A cross-sectional schematic diagram (5) illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0048] Figure 1F A cross-sectional schematic diagram (6) illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0049] Figure 1G A cross-sectional schematic diagram (7) is provided for illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0050] Figure 1H A cross-sectional schematic diagram (8) illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0051] Figure 1I A cross-sectional schematic diagram (9) illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0052] Figure 2 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 1.

[0053] Figure 3 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 2.

[0054] Figure 4 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 3.

[0055] Figure 5 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 4.

[0056] Figure 6 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 5.

[0057] Figure 7 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 6.

[0058] Figure 8 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Example 7.

[0059] Figure 9 Electron microscopy (SEM) images of the microphase separation structure of a self-assembled membrane formed on a lower membrane formed from the lower membrane forming composition of Comparative Example 1. Detailed Implementation

[0060] (Composition for lower layer film formation)

[0061] The composition for forming a lower layer film of the present invention is a composition for forming a lower layer film for forming a self-assembled film.

[0062] The composition for forming the lower film contains a polymer.

[0063] The polymer has a unit structure (A), which has an alicyclic hydrocarbon group with a reactive group.

[0064] The composition for forming a lower membrane contains a polymer having a unit structure (A) having an alicyclic hydrocarbon group having a reactive group, thereby forming a lower membrane that can be vertically aligned as a lower membrane for self-assembling membrane formation.

[0065] <Polymer>

[0066] The polymer has a unit structure (A) having an alicyclic hydrocarbon group with a reactive group. Hereinafter, this polymer will sometimes be referred to as "a specific polymer".

[0067] <<Unit Structure (A)>>

[0068] Unit structure (A) is a unit structure with an alicyclic hydrocarbon group having a reactive group.

[0069] Examples of alicyclic hydrocarbon groups in unit structure (A) include cyclohexyl, isobornyl, dicyclopentyl, adamantyl, cyclopropyl, cyclobutyl, and cyclopentyl, with cyclohexyl, isobornyl, dicyclopentyl, and adamantyl being preferred. Furthermore, the alicyclic hydrocarbon group may have substituents other than the reactive group.

[0070] As an alicyclic hydrocarbon group, the number of carbon atoms is preferably 7 to 14, more preferably 8 to 12.

[0071] Examples of reactive groups in unit structure (A) include hydroxyl, epoxy, acyl, acetyl, formyl, benzoyl, carboxyl, carbonyl, amino, imino, cyano, azo, azido, thiol, sulfonyl, and allyl. Hydroxyl groups are preferred among these reactive groups. The presence of one or more reactive groups relative to an alicyclic hydrocarbon group is acceptable, but one relative to an alicyclic hydrocarbon group is preferred.

[0072] There are no particular limitations on the unit structure (A), but from the viewpoint of obtaining the effects of the present invention, the unit structure shown in the following formula (A-1) is preferred.

[0073]

[0074] (In equation (A-1), R) 1 Represents a hydrogen atom or a methyl group. X 1 Indicates a single bond, ester group, or amide group. Y 1 Indicates a single bond or an alkylene group having 1 to 6 carbon atoms. Cy represents an alicyclic hydrocarbon group with a reactive group.

[0075] In equation (A-1), Y 1 It indicates a single bond or a divalent alkylene group with 1 to 6 carbon atoms.

[0076] Examples of divalent alkylene groups having 1 to 6 carbon atoms include methylene, ethylene, propylene, 1,3-propylene, butylene, pentylene, and hexylene.

[0077] In equation (A-1), X 1 Preferably, it is an ester group, Y1 Single bonds are preferred.

[0078] Cy represents an alicyclic hydrocarbon group with a reactive group.

[0079] The reactive group in Cy is preferably a hydroxyl group, and the alicyclic hydrocarbon group is preferably an adamantyl group.

[0080] As an example of the unit structure shown in equation (A-1), the following unit structures can be cited.

[0081]

[0082] The unit structure (A) in the polymer can be one or more, but preferably one or two.

[0083] <<Unit Structure (B)>>

[0084] The polymers of the present invention may have unit structures other than unit structure (A). As such unit structures, from the viewpoint of obtaining the effects of the present invention, the unit structure shown in the following formula (B-1) can be cited as an example.

[0085]

[0086] (In equation (B-1), R) 11 This indicates a hydrogen atom or a methyl group. Ar 11 (This indicates an aromatic group that can be substituted.)

[0087] In equation (B-1), Ar 11 Examples of substances that can be substituted include naphthalene, anthracene, phenanthrene, pyrene, benzo[9,10]phenanthrene, and others. , tetraphenylene, biphenylene, fluorene or carbazole, etc.

[0088] As Ar 11 The substituents that can be present include, for example, halogen atoms, hydroxyl groups, alkyl groups, alkoxy groups, thiols, cyano groups, carboxyl groups, amino groups, amide groups, alkoxycarbonyl groups, alkylthio groups, etc.

[0089] Ar in equation (B-1) 11 It can also be benzene with one or more substituents, such as hydrocarbon groups having 1 to 6 carbon atoms. 11 The hydrocarbon group can be any of straight-chain, branched, or cyclic, with branched being preferred. As Ar 11 Of the hydrocarbon groups in the sample, tert-butyl is preferred.

[0090] Ar 11 The hydrocarbon group in the sample only needs to have one or two or more hydrocarbon groups.

[0091] Ar in equation (B-1) 11The number of carbon atoms is preferably 6 to 20, more preferably 6 to 14.

[0092] As shown in equation (B-1), the following unit structures can be cited as examples.

[0093]

[0094] The unit structure (B-1) in the polymer can be one or more types, but preferably one or two types.

[0095] <<Unit Structure (C)>>

[0096] The polymer can have unit structures other than those of unit structures (A) and (B). From the viewpoint of achieving the effects of the present invention, a unit structure (C) having a monocyclic aromatic structure can be cited as an example of such a unit structure.

[0097] It should be noted that the unit structure (C) is a different unit structure from the unit structures (A) and (B).

[0098] For example, unit structure (C) does not have an alicyclic hydrocarbon group with a reactive group, as has unit structure (A). Furthermore, unit structure (C) does not have benzene with one or more hydrocarbon groups having 1 to 6 carbon atoms as substituents, as has unit structure (B).

[0099] There are no particular limitations on the unit structure (C), but from the viewpoint of obtaining the effects of the present invention, the unit structure shown in the following formula (C-1) is preferred.

[0100]

[0101] (In equation (C-1), R) 21 Represents a hydrogen atom or a methyl group. X 21 Indicates an ester group or an amide group. Y 21 Indicates a single bond or an alkylene group having 1 to 6 carbon atoms. Z 21 Indicates a single bond or an ether group. Ar 21 Indicates that benzene, naphthalene, or anthracene can be substituted. R 22 This represents a halogen atom or an organogroup with 1 to 10 carbon atoms that can be substituted. n represents an integer from 0 to 5. In R... 22 When there are two or more R's 22 They can be the same or different.

[0102] X 21 Preferably, it is an ester group.

[0103] R22 The organic group that can be substituted with 1 to 10 carbon atoms is preferably an alkyl group that can be substituted with 1 to 6 carbon atoms, an alkoxy group that can be substituted with 1 to 6 carbon atoms, or an acyl group that can be substituted with 2 to 10 carbon atoms.

[0104] Examples of acyl groups that can be replaced by halogen atoms and have 2 to 10 carbon atoms include benzoyl group.

[0105] Typically, in Y 21 In the case of a single key, Z 21 Indicates a single key.

[0106] The unit structure shown in formula (C-1) preferably has 9 to 19 carbon atoms.

[0107] As shown in equation (C-1), the following unit structures can be cited as examples.

[0108]

[0109] The unit structure (C) in the vinyl polymer can be one or more, but preferably one or two.

[0110] <<Unit Structure (D)>>

[0111] The polymer can have unit structures other than unit structures (A), (B), and (C). From the viewpoint of achieving the effects of the present invention, a unit structure (D) having a hydrocarbon group having a reactive group (however, excluding alicyclic hydrocarbon groups) can be cited as such a unit structure.

[0112] It should be noted that the unit structure (D) is a different unit structure from the unit structures (A), (B), and (C).

[0113] For example, unit structure (D) does not have the alicyclic hydrocarbon group with reactive groups that unit structure (A) has.

[0114] There are no particular limitations on the unit structure (D), but from the viewpoint of obtaining the effects of the present invention, the unit structure shown in the following formula (D-1) is preferred.

[0115]

[0116] (In equation (D-1), R) 31 Represents a hydrogen atom or a methyl group. X 31 Indicates an ester group or an amide group. R 32 This refers to a hydrocarbon group with 1 to 12 carbon atoms that has a reactive group (excluding alicyclic hydrocarbon groups).

[0117] Examples of hydrocarbon groups having 1 to 12 carbon atoms in the unit structure (D-1) include alkyl groups having 1 to 12 carbon atoms.

[0118] Some of the hydrogen atoms in these alkyl groups can be replaced by monocyclic aromatic hydrocarbon rings such as benzene rings.

[0119] Examples of reactive groups that can be found in the unit structure (D-1) include hydroxyl, epoxy, acyl, acetyl, formyl, benzoyl, carboxyl, carbonyl, amino, imino, cyano, azo, azido, thiol, sulfonyl, and allyl groups. Hydroxyl groups are preferred among these reactive groups. It is acceptable for the reactive group to be one or more relative to a hydrocarbon group, but one relative to a hydrocarbon group is preferred.

[0120] As shown in equation (D-1), the following unit structures can be cited as examples.

[0121]

[0122] There is no particular limitation on the molar ratio of unit structure (A) to the total unit structure of the polymer, but from the viewpoint of obtaining the effects of the present invention, it is preferably less than 60 mol%, more preferably 50 mol% or less, and particularly preferably 45 mol% or less.

[0123] The molar ratio of unit structure (A) to all unit structures of the polymer is preferably 5 mol% or more, more preferably 10 mol% or more, and particularly preferably 15 mol% or more.

[0124] There is no particular limitation on the molar ratio of the unit structure (B-1) to the total unit structure of the polymer, but from the viewpoint of obtaining the effects of the present invention, it is preferably 45 mol% or more, more preferably 50 mol% or more, and particularly preferably 55 mol% or more.

[0125] The molar ratio of unit structure (B-1) to all unit structures of the vinyl polymer is preferably 80 mol% or less, more preferably 70 mol% or less, and particularly preferably 60 mol% or less.

[0126] When the polymer has a unit structure (C), there is no particular limitation on the molar ratio of the unit structure (C) to the total unit structure of the polymer, but from the viewpoint of obtaining the effect of the present invention, it is preferably 5 mol% or more, more preferably 15 mol% or more, and particularly preferably 20 mol% or more.

[0127] The molar ratio of unit structure (C) to the total unit structure of the polymer is preferably 50 mol% or less, more preferably 40 mol% or less, and particularly preferably 30 mol% or less.

[0128] When the polymer has a unit structure (D), there is no particular limitation on the molar ratio of the unit structure (D) to the total unit structure of the polymer, but from the viewpoint of obtaining the effect of the present invention, it is preferably 5 mol% or more, more preferably 10 mol% or more, and particularly preferably 15 mol% or more.

[0129] The molar ratio of unit structure (D) to the total unit structure of the polymer is preferably 50 mol% or less, more preferably 40 mol% or less, and particularly preferably 30 mol% or less.

[0130] The molar ratio of unit structure (A) to unit structure (B-1) in the polymer (unit structure (B-1) / unit structure (A)) is not particularly limited, but is preferably 1 to 9, and more preferably 1.5 to 5.

[0131] There are no particular restrictions on the distribution of unit structures in the polymer. The polymer can be a block copolymer or a random copolymer.

[0132] There are no particular limitations on the molecular weight of the polymer, but the weight-average molecular weight obtained by gel permeation chromatography (hereinafter, sometimes simply referred to as GPC) is preferably 1,500 to 100,000, more preferably 2,000 to 50,000.

[0133] The molecular weight of the polymer can be determined, for example, using a GPC apparatus (EcoSEC, HLC-8320GPC manufactured by Higashi Sou Co., Ltd.) and a GPC column (Shodex [registered trademark] and Asahipak [registered trademark] manufactured by Showa Denko Co., Ltd.), with the column temperature set to 40°C, dimethylformamide used as the eluent, the flow rate set to 0.6 mL / min, and polystyrene (manufactured by Higashi Sou Co., Ltd.) used as the standard sample.

[0134] <<Methods for Manufacturing Polymers>>

[0135] There are no particular limitations on the manufacturing method of the specific polymer. For example, the specific polymer of this embodiment can be obtained by reacting the carbon-carbon double bonds of the monomer providing unit structure (A), the carbon-carbon double bonds of the monomer providing optional unit structure (B), the carbon-carbon double bonds of the monomer providing optional unit structure (C), and the carbon-carbon double bonds of the monomer providing optional unit structure (D).

[0136] As for the polymerization method of a specific polymer, well-known polymerization methods such as free radical polymerization, anionic polymerization, and cationic polymerization can be used. Various well-known techniques such as solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization can also be used.

[0137] There are no particular limitations on the polymerization initiator used during polymerization, and examples such as 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylpentanonitrile), 4,4'-azobis(4-cyanopentanoic acid), 2,2'-azobis(2,4-dimethylpentanonitrile), and 2,2'-azobis(4-methoxy-2,4-dimethyl) Examples of acetonitrile include 2,2'-azobis(isobutyronitrile), 1,1'-azobis(cyclohexane-1-carboxylonitrile), 1-[(1-cyano-1-methylethyl)azo]formamide, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane], and 2,2'-azobis(2-methylpropanediamine) dihydrochloride.

[0138] As a solvent used in polymerization, there are no particular restrictions; for example, dimethyl ether can be used. Alkane, 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 monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxylate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, etc. These can be used alone or in combination.

[0139] There are no particular restrictions on the reaction temperature; examples include 20°C to 150°C.

[0140] There are no particular limitations on the reaction time; examples include 1 hour to 72 hours.

[0141] The resulting polymer-containing solution can also be used directly for the preparation of compositions for lower membrane formation. Alternatively, the polymer can be precipitated and separated in unsuitable solvents such as methanol, ethanol, isopropanol, water, or mixtures thereof for recycling.

[0142] The content of a specific polymer in the composition for forming the lower layer film is not particularly limited, but from the viewpoint of solubility, it is preferably 0.1% to 50% by mass, more preferably 0.1% to 10% by mass, relative to the entire composition for forming the lower layer film.

[0143] Furthermore, the content of a specific polymer in the composition for forming the lower layer film is preferably 50% to 95% by mass, more preferably 55% to 90% by mass, and particularly preferably 60% to 85% by mass, relative to the film composition.

[0144] The term "membrane composition" refers to the components in a composition other than the solvent.

[0145] <Cross-linking agent>

[0146] The composition for forming the lower film preferably contains a crosslinking agent.

[0147] The crosslinking agent has, for example, functional groups that can react with the reactive groups present in the unit structure (A).

[0148] There is no particular limitation on the number of this functional group in the crosslinking agent; it can be one or more.

[0149] There are no particular limitations on the functional group that can react with the reactive group present in the unit structure (A), and examples include, for example, hydroxyl, epoxy, acyl, acetyl, formyl, benzoyl, carboxyl, carbonyl, amino, imino, cyano, azo, azido, thiol, sulfonyl, allyl, and structures shown in the following formula (E).

[0150]

[0151] (In equation (E), R) 101 This indicates a hydrogen atom, an alkyl group with 1 to 4 carbon atoms, or an alkoxyalkyl group with 2 to 6 carbon atoms. * indicates a bonding bond.

[0152] Bonding bonds include, for example, bonds with nitrogen atoms or carbon atoms that form aromatic hydrocarbon rings.

[0153] When the reactive group in unit structure (A) is a hydroxyl or thiol group, for example, the structure shown in formula (E) can be cited as a functional group that can react with the reactive group in unit structure (A).

[0154] When the reactive group of the unit structure (A) is an epoxy group, for example, functional groups that can react with the reactive group of the unit structure (A) include, for example, carboxyl, amino, thiol groups, etc.

[0155] Examples of crosslinking agents include compounds having two or more of the structures shown in formula (E) below.

[0156] As R 101 Preferably, it contains hydrogen atoms, methyl, ethyl or groups represented by the following structures.

[0157]

[0158] (In the structure, R) 102 * Represents a hydrogen atom, methyl group, or ethyl group. * Represents a bond.

[0159] Preferred crosslinking agents include melamine compounds, guanidine compounds, glycourea compounds, urea compounds, and compounds with phenolic hydroxyl groups. They can be used alone or in combination of two or more.

[0160] As a melamine compound, there is no particular limitation as long as it has a group that can react with the reactive group (e.g., hydroxyl group) present in the unit structure (A).

[0161] Examples of melamine compounds include, for example, hexamethylolmelamine, hexamethoxymethylmelamine, compounds of hexamethylolmelamine in which 1 to 6 hydroxymethyl groups are methoxymethylated, or mixtures thereof, hexamethoxyethylmelamine, hexaacyloxymethylmelamine, compounds of hexamethylolmelamine in which 1 to 6 hydroxymethyl groups are acyloxymethylated, or mixtures thereof.

[0162] As a guanidine compound, there is no particular limitation as long as it has a group that can react with the reactive group (e.g., hydroxyl group) present in the unit structure (A).

[0163] Examples of guanidine compounds include, for example, tetrahydroxymethylguanidine, tetramethoxymethylguanidine, compounds of tetrahydroxymethylguanidine in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, tetramethoxyethylguanidine, tetraacyloxyguanidine, compounds of tetrahydroxymethylguanidine in which 1 to 4 hydroxymethyl groups are acyloxymethylated, or mixtures thereof.

[0164] As a glycourea compound, there is no particular limitation as long as it has a group that can react with the reactive group (e.g., hydroxyl group) present in the unit structure (A).

[0165] Examples of glycourea compounds include, for example, tetrahydroxymethylglycourea, tetramethoxyglycourea, tetramethoxymethylglycourea, compounds of tetrahydroxymethylglycourea in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, compounds of tetrahydroxymethylglycourea in which 1 to 4 hydroxymethyl groups are acylmethylated, or mixtures thereof.

[0166] In addition, as a glycourea compound, it can also be a glycourea derivative as shown in formula (1E) below.

[0167]

[0168] (In formula (1E), each of the four R1s independently represents a methyl or ethyl group, and each of the R2 and R3 independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group.)

[0169] Examples of compounds shown in formula (1E) to (1E-6) below are glycourea derivatives shown in formula (1E) above.

[0170]

[0171] The glycourea derivative shown in formula (1E) can be obtained, for example, by reacting the glycourea derivative shown in formula (2E) with at least one of the compounds shown in formula (3d).

[0172]

[0173] (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.)

[0174] (In formula (3d), R1 represents methyl or ethyl.)

[0175] Examples of compounds shown in formula (2E) to (2E-4) below are examples of glycourea derivatives. Further examples of compounds shown in formula (3d) below are examples of compounds shown in formula (3d-1) and (3d-2).

[0176]

[0177] As a urea compound, there is no particular limitation as long as it is a urea compound having a group that can react with the reactive group (e.g., hydroxyl group) present in the unit structure (A).

[0178] Examples of urea compounds include tetrahydroxymethylurea, tetramethoxymethylurea, compounds of tetrahydroxymethylurea in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, and tetramethoxyethylurea.

[0179] Examples of compounds having phenolic hydroxyl groups include compounds represented by formula (111) or formula (112) below.

[0180]

[0181] (In equations (111) and (112), Q) 2 It represents a single bond or an m2 valence organic group.

[0182] R 8 R 9 R 11 and R 12 Each represents a hydrogen atom or a methyl group.

[0183] R 7 and R 10 Each represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms.

[0184] n9 represents an integer where 1 ≤ n9 ≤ 3, n 10 It means 2≤n 10 Integers ≤ 5, n 11 It means 0≤n 11 Integers ≤ 3, n 12 It means 0≤n 12 Integers ≤ 3, and n = 9, n 10 n 11 n 12 This means 3 ≤ (n9 + n) 10 +n 11 +n 12 Integers ≤ 6.

[0185] n 13 It means 1≤n 13 Integers ≤ 3, n 14 It means 1≤n 14 Integers ≤ 4, n 15 It means 0≤n 15 Integers ≤ 3, n 16 It means 0≤n 16 Integers ≤ 3, and n 13 n 14 n 15 n 16 It means 2≤(n) 13 +n 14 +n 15 +n 16 Integers ≤ 5.

[0186] m2 represents an integer from 2 to 10.

[0187] As Q 2 Examples of m2-valent organic groups include those with 1 to 4 carbon atoms.

[0188] Examples of compounds represented by formula (111) or formula (112) include the following compounds.

[0189]

[0190] The above-mentioned compounds can be obtained as products manufactured by Asahi Organic Materials Co., Ltd. and Honshu Chemical Co., Ltd. For example, Asahi Organic Materials Co., Ltd.'s trade name TMOM-BP can be cited as an example of such a product.

[0191] Among them, glycourea compounds are preferred, specifically tetrahydroxymethylglycourea, tetramethoxyglycourea, tetramethoxymethylglycourea, compounds of tetrahydroxymethylglycourea with 1 to 4 hydroxymethyl groups methoxymethylated or mixtures thereof, compounds of tetrahydroxymethylglycourea with 1 to 4 hydroxymethyl groups acylmethylated or mixtures thereof, with tetramethoxymethylglycourea being the most preferred.

[0192] There are no particular limitations on the molecular weight of the crosslinking agent, but it is preferably below 1000.

[0193] The content of the crosslinking agent in the composition for forming the lower film is not particularly limited, but it is preferably 5% to 60% by mass of a specific polymer, more preferably 10% to 55% by mass, and particularly preferably 20% to 50% by mass.

[0194] <Cure-up Catalyst>

[0195] Regarding the curing catalyst included as an optional component in the composition for forming the lower film, both thermal acid-generating agents and photo-acid-generating agents can be used, but thermal acid-generating agents are preferred.

[0196] Examples of heat-generating acid agents include p-toluenesulfonic acid, trifluoromethanesulfonic acid, and pyridine. - p-Toluenesulfonate (pyridine) -p-Toluenesulfonic acid), pyridine Phenolsulfonic acid, pyridine - p-Hydroxybenzenesulfonic acid (p-phenolsulfonic acid pyridine) salt), pyridine - Sulfonic acid compounds and carboxylic acid compounds such as trifluoromethanesulfonic acid, salicylic acid, camphor sulfonic acid, 5-sulfosalicylic acid, 4-chlorobenzenesulfonic acid, 4-hydroxybenzenesulfonic acid, benzene disulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, N-methylmorpholine-p-toluenesulfonic acid, N-methylmorpholine-p-hydroxybenzenesulfonic acid, and N-methylmorpholine-5-sulfosalicylic acid.

[0197] Examples of photoacid-generating agents include, Salt compounds, sulfonylimide compounds, and disulfonyldiazomethane compounds, etc.

[0198] As Salt compounds, for example, diphenyliodine Hexafluorophosphate, diphenyliodine Trifluoromethanesulfonate, diphenyliodine Nonafluoro-n-butane sulfonate, diphenyl iodide Perfluorooctane sulfonate, diphenyl iodide Camphor sulfonate, bis(4-tert-butylphenyl)iodine Camphor sulfonate and bis(4-tert-butylphenyl)iodine Iodine, such as trifluoromethanesulfonate Salt compounds and sulfonium salt compounds such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium nonafluoro n-butane sulfonate, triphenylsulfonium camphor sulfonate and triphenylsulfonium trifluoromethane sulfonate.

[0199] Examples of sulfonylimide compounds include N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoron-butanesulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide, and N-(trifluoromethanesulfonyloxy)naphthalenediformimide.

[0200] Examples of disulfonyldiazomethane compounds include, for example, bis(trifluoromethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methylsulfonyl-p-toluenesulfonyldiazomethane.

[0201] A single solidification catalyst may be used, or two or more may be used in combination.

[0202] When using a curing catalyst, the content of the curing catalyst relative to the crosslinking agent is, for example, 0.1% to 50% by mass, preferably 1% to 30% by mass.

[0203] <Other Ingredients>

[0204] In the composition for forming the lower film, a surfactant can be added to further improve the coating properties on uneven surfaces in order to prevent pinholes, streaks, etc.

[0205] Examples of surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oil-based ether; polyoxyethylene alkyl aryl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether; polyoxyethylene / polyoxypropylene block copolymers; sorbitol monolaurate, sorbitol monopalmitate, sorbitol monostearate, sorbitol monooleate, sorbitol trioleate, and sorbitol tristearate; and polyoxyethylene sorbitol monolaurate, polyoxyethylene sorbitol monopalmitate, polyoxyethylene sorbitol monostearate, polyoxyethylene sorbitol trioleate, and polyoxyethylene... Nonionic surfactants such as sorbitan tristearate and polyoxyethylene sorbitan fatty acid esters; Eptop EF301, EF303, EF352 (manufactured by Tokem Prodact, trade name); Megafack F171, F173, R-30 (manufactured by DIC Co., Ltd., trade name); Florad FC430, FC Fluorinated surfactants such as 431 (manufactured by Sumitomo Silem Co., Ltd., trade name), Asahigard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by AGC Co., Ltd., trade name), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

[0206] There are no particular restrictions on the amount of these surfactants mixed, but they are generally 2.0% by mass or less, preferably 1.0% by mass or less, relative to the composition for forming the underlying film.

[0207] These surfactants can be added individually or in combination of two or more.

[0208] <Solvent>

[0209] The composition for forming the lower film may contain a solvent.

[0210] As a solvent, organic solvents commonly used in semiconductor photolithography processes are preferred. Specifically, examples 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, cyclopentanone, cyclohexanone, cycloheptanone, 4-methyl-2-pentanol, and methyl 2-hydroxyisobutyrate. Ethyl 2-hydroxyisobutyrate, ethyl ethoxylate, 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 alone or in combination of two or more.

[0211] Preferred solvents include propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, and cyclohexanone. Propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are particularly preferred solvents.

[0212] The content of solvent in the composition for forming the lower film is not particularly limited, but is preferably 80% to 99.99% by mass, more preferably 90% to 99.95% by mass, and particularly preferably 95% to 99.9% by mass.

[0213] (Lower membrane)

[0214] The lower layer film of the present invention is a sintered product of the coated film of the composition for forming the lower layer film described above.

[0215] The lower layer membrane of the present invention is used as the lower layer membrane of a self-assembled membrane.

[0216] The lower layer film of the present invention can be used as a lower layer film for self-assembly after being used as a lower layer film for photolithography using any of the photoresist film and electron beam photoresist film and self-assembly film.

[0217] The lower layer film of the present invention can be manufactured, for example, by coating a lower layer film forming composition onto a semiconductor substrate and then firing it.

[0218] Examples of semiconductor substrates for coating the lower film forming composition of the present invention include silicon wafers, germanium wafers, and compound semiconductor wafers such as gallium arsenide, indium phosphide, gallium nitride, indium nitride, and aluminum nitride.

[0219] When using a semiconductor substrate on which an inorganic film has been formed on its surface, this inorganic film can be formed, for example, by ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum evaporation, or spin coating (SOG). Examples of such inorganic films include, for instance, polycrystalline silicon films, silicon oxide films, silicon nitride films, BPSG (boro-phosphorus silicon glass) films, titanium nitride films, titanium oxide nitride films, tungsten films, gallium nitride films, and gallium arsenide films.

[0220] Semiconductor substrates can also have films containing silicon and organic groups. A film containing silicon and organic groups is a film formed by the hydrolysis condensation of a hydrolyzable silane (also called an organosilicon compound) containing an organic group. A film containing silicon and organic groups comprises, for example, a hydrolysis condensation of a hydrolyzable silane containing a compound represented by formula (A) below.

[0221]

[0222] (In equation (A), R) a Represents alkyl, aryl, haloalkyl, haloaryl, alkoxyaryl, alkenyl, epoxy group, acryloyl group, methacryloyl group, mercapto group, or cyano group; R b (This represents an alkoxy, acyloxy, or halogen atom, where x represents an integer from 0 to 3.)

[0223] Films containing silicon and organic groups can be formed, for example, by a silicon-containing photoresist underlayer film forming composition. Examples of such silicon-containing photoresist underlayer film forming compositions include, for example, the silicon-containing photoresist underlayer film forming compositions described below.

[0224] Japanese Patent Application Publication No. 2020-076999, Booklet No. WO2019 / 181873, Booklet No. WO2019 / 082934, Booklet No. WO2019 / 009413, Booklet No. WO2018 / 181989, Booklet No. WO2018 / 079599, Booklet No. WO2016 / 080217, Booklet No. WO2016 / 009965, Booklet No. WO2016 / 009939, Booklet No. WO2015 / 194555, Booklet No. WO2014 / 098076, Booklet No. WO2014 / 069329, Booklet No. WO2014 / 046055, Booklet No. WO2013 / 191203 Booklet No. WO2013 / 115032, Booklet No. WO2013 / 022099, Booklet No. WO2012 / 102261, Booklet No. WO2012 / 053600, Booklet No. WO2012 / 039337, Booklet No. WO2011 / 105368, Booklet No. WO2011 / 102470, Booklet No. WO2011 / 033965, Booklet No. WO2010 / 140551, Booklet No. WO2010 / 071155, Booklet No. WO2010 / 021290, Booklet No. WO2009 / 104552, Booklet No. WO2009 / 088039, Booklet No. WO2009 / 069712

[0225] The composition for forming the lower layer film of the present invention is coated on such a semiconductor substrate using a suitable coating method such as a spin coater or a coating machine. Then, it is baked using a heating means such as a heating plate to form a photoresist lower layer film. The baking conditions are appropriately selected from a baking temperature of 100°C to 400°C and a baking time of 0.3 minutes to 60 minutes. Preferably, the baking temperature is 120°C to 350°C and the baking time is 0.5 minutes to 30 minutes; more preferably, the baking temperature is 150°C to 300°C and the baking time is 0.8 minutes to 10 minutes.

[0226] From the viewpoint of achieving the effects of the present invention, the thickness of the lower layer film is preferably less than 10 nm, more preferably 9 nm or less, even more preferably 8 nm or less, and particularly preferably 7 nm or less. Furthermore, the thickness of the lower layer film can be 1 nm or more, 2 nm or more, or 3 nm or more.

[0227] Generally, if the thickness of the underlying resist film is thin, it is difficult to obtain a film with a flat surface. In the case of an uneven surface, the thickness variation of the resist film formed on the underlying film becomes larger, and as a result, the roughness of the resist pattern can be considered to be increased.

[0228] The composition for forming the lower film of the present invention contains the aforementioned vinyl polymer, thereby tending to obtain a lower film with excellent adhesion to the substrate and film-forming properties. Therefore, it is presumed that even if the thickness of the lower film is less than 10 nm, a film with a flat surface can be formed, which can improve the roughness (LWR, CDU) of the resist pattern. The aforementioned LWR (Linewidth roughness) is mainly an evaluation of the resist pattern being lines and gaps (wiring pattern), but the lower film of this application also shows an effect on improving CDU (Critical Dimension Uniformity, CD Uniformity, CD uniformity) (less fluctuation in aperture) when the resist pattern is a contact hole (hole pattern).

[0229] The aforementioned CDU can be evaluated, for example, by the method described in Japanese Patent Application Publication No. 2020-003678 (paragraph

[0386] Evaluation of in-plane uniformity (CDU) of pattern dimensions).

[0230] Furthermore, when a brush layer is formed in the gaps between the patterns of the patterned lower film, the brush layer becomes a thin layer (e.g., about 1 nm). From the viewpoint of minimizing the difference in film thickness between the brush layer and the lower film, the film thickness of the lower film is preferably thin. In this respect, the film thickness of the lower film is preferably less than 10 nm.

[0231] Furthermore, by making the lower layer thin, it is easier to transfer the pattern of the patterned self-assembled film onto the lower layer. In this respect, the thickness of the lower layer is preferably less than 10 nm.

[0232] The method for determining the thickness of the lower layer membrane in this specification is as follows.

[0233] Name of measuring device: Elliptic film thickness measuring device RE-3100 (SCREEN Co., Ltd.) SWE (Single Wavelength Ellipsometry) Mode The arithmetic mean of 8 points (e.g., measured at 1 cm intervals along the X direction of the wafer). (Semiconductor device manufacturing methods) One embodiment of the semiconductor device of the present invention includes a first process and a second process.

[0234] Step I: The step of forming a lower layer film on a semiconductor substrate using the lower layer film forming composition of the present invention. Step II: The process of forming a self-assembled membrane on the lower membrane. Other embodiments of the semiconductor device manufacturing method of the present invention include steps 1 to 5.

[0235] Step 1: The step of forming a lower layer film on a semiconductor substrate using the lower layer film forming composition of the present invention. Step 2: The step of forming either a photoresist film or an electron beam resist film on the lower layer film. Step 3: Irradiate the resist film with light or electron beam, then develop the resist film to obtain the resist pattern. Step 4: Using the resist pattern as a mask, the underlying film is etched to form the patterned underlying film. Step 5: The process of forming a self-assembled film on the patterned lower film. Other embodiments of the method for manufacturing the semiconductor element of the present invention, which includes steps 1 to 5, may further include a 6th step.

[0236] Step 6: The process of forming a brush layer in the gaps between the patterns on the patterned lower film.

[0237] It should be noted that the sixth step is the step performed between the fourth and fifth steps.

[0238] <Process 1 and Process I>

[0239] Step 1 and Step I are steps of forming a lower layer film on a semiconductor substrate using the lower layer film forming composition of the present invention. There are no particular limitations on the method for forming the lower layer film, and the methods described above can be cited as examples. That is, the lower layer film can be manufactured, for example, by coating the lower layer film forming composition onto a semiconductor substrate and then firing it.

[0240] From the viewpoint of achieving the effects of the present invention, the thickness of the lower layer film is preferably less than 10 nm, more preferably 9 nm or less, even more preferably 8 nm or less, and particularly preferably 7 nm or less. Furthermore, the thickness of the lower layer film can be 1 nm or more, 2 nm or more, or 3 nm or more.

[0241] <Process 2, Process 3, and Process 4>

[0242] The second step is to form either a photoresist film or an electron beam resist film on the lower layer film.

[0243] The third step involves irradiating the resist film with light or an electron beam, followed by developing the resist film to obtain a resist pattern.

[0244] The fourth step involves etching the underlying film using the resist pattern as a mask to form a patterned underlying film.

[0245] The thickness of the resist film to be formed is not particularly limited, but 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 even more preferably 30 nm or more.

[0246] As a photoresist formed by coating and firing on a lower film using known methods, there are no particular limitations as long as it responds to the light or electron beam (EB) used for irradiation. Both negative and positive photoresists can be used.

[0247] It should be noted that the EB-responsive resist in this specification is sometimes referred to as a photoresist.

[0248] As photoresists, there are positive photoresists composed of phenolic varnish resin and 1,2-naphthoquinone diazonyl sulfonate; chemically amplified photoresists composed of binders and photoacid generators having groups that increase the rate of alkali dissolution through acid decomposition; chemically amplified photoresists composed of low-molecular-weight compounds that increase the rate of alkali dissolution through acid decomposition, alkali-soluble binders, and photoacid generators; chemically amplified photoresists composed of binders that increase the rate of alkali dissolution through acid decomposition, low-molecular-weight compounds that increase the rate of alkali dissolution through acid decomposition, and photoacid generators; and photoresists containing metal elements, etc. Examples of such photoresists include those manufactured by JSR Corporation under the trade name V146G, those manufactured by Shiplay Corporation under the trade name APEX-E, those manufactured by Sumitomo Chemical Co., Ltd. under the trade name PAR710, and those manufactured by Shin-Etsu Chemical Industry Co., Ltd. under the trade names AR2772 and SEPR430. Furthermore, examples of fluorinated atom polymer-based photoresists can be found in publications such as Proc. SPIE, Vol. 3999, 330-334 (2000), Proc. SPIE, Vol. 3999, 357-364 (2000), and Proc. SPIE, Vol. 3999, 365-374 (2000).

[0249] In addition, the following can be used: 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, WO2019 / 172054, W O2019 / 021975, WO2018 / 230334, WO2018 / 194123, Japanese Special Opening 2018-180525, WO2018 / 190088, Japanese Special Opening 2018-070596, Japanese Special Opening 2018-028090, Japanese Special Opening 2016-153409, Japanese Special Opening 2016-130240, Japanese Special Opening 2016-108325, Japanese Special Opening 2016-047920, Japanese Special Opening 2016-035570, Japan Special opening 2016-035567, Japanese special opening 2016-035565, Japanese special opening 2019-101417, Japanese special opening 2019-117373, Japan Special Opening 2019-052294, Japanese Special Opening 2019-008280, Japanese Special Opening 2019-008279, Japanese Special Opening 2019-003176, Japanese Special Opening 2019-003175, Japanese Special Opening 2018-197853, Japanese Special Opening 2019-191298, Japanese Special Opening 2019-06 1217. Japan Special Opening 2018-045152, Japanese Special Opening 2018-022039, Japanese Special Opening 2016-090441, Japanese Special Opening 2015-10878, Japanese Special Opening 2012-168279, Japanese Special Opening 2012-022261, Japanese Special Opening 2012-022258, Japanese Special Opening 201 The so-called resist compositions, such as resist compositions, radiation-sensitive resin compositions, and high-resolution pattern forming compositions based on organometallic solutions, as described in 1-043749, Japanese Patent Application Publication No. 2010-181857, Japanese Patent Application Publication No. 2010-128369, WO2018 / 031896, Japanese Patent Application Publication No. 2019-113855, WO2017 / 156388, WO2017 / 066319, Japanese Patent Application Publication No. 2018-41099, WO2016 / 065120, WO2015 / 026482, Japanese Patent Application Publication No. 2016-29498, and Japanese Patent Application Publication No. 2011-253185, are not limited to these.

[0250] Examples of resist compositions include the following.

[0251] An active light-sensitive or radiation-sensitive resin composition comprising resin A and a compound represented by the following general formula (21), wherein resin A has repeating units having acid-degradable groups protected by protecting groups whose polar groups are removed by the action of acid.

[0252]

[0253] In general formula (21), m represents an integer from 1 to 6.

[0254] R1 and R2 each independently represent a fluorine atom or a perfluoroalkyl group.

[0255] L1 represents -O-, -S-, -COO-, -SO2-, or -SO3-.

[0256] L2 indicates that it can have alkylene groups or single bonds that have substituents.

[0257] W1 represents a cyclic organic group that can have substituents.

[0258] M ＋ It represents a cation.

[0259] A metal-containing film-forming composition for 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.

[0260] A radiation-sensitive resin composition comprising a polymer and an acid-generating agent, wherein the polymer has a first structural unit represented by the following formula (31) and a second structural unit represented by the following formula (32) and containing an acid-dissociating group.

[0261]

[0262] (In formula (31), Ar is a group from aromatic hydrocarbons with 6 to 20 carbon atoms from which (n+1) hydrogen atoms have been removed. R 1 It is a hydroxyl group, a thiol group, or a monovalent organic group with 1 to 20 carbon atoms. n is an integer from 0 to 11. When n is 2 or more, multiple R... 1 Same or different. R 2 R can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. In formula (32), R 3 It is a monovalent group containing 1 to 20 carbon atoms, comprising the aforementioned acid-dissociating group. Z is a single bond, an oxygen atom, or a sulfur atom. R 4 (It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.)

[0263] An anti-corrosion composition comprising a resin (A1) and an acid-generating agent, wherein the resin (A1) comprises structural units having a cyclic carbonate structure, structural units shown in the following formula, and structural units having acid-instantaneous groups.

[0264]

[0265] [In the formula,] R 2 X represents an alkyl group, hydrogen atom, or halogen atom that can have 1 to 6 carbon atoms and may contain halogen atoms. 1 Indicates a single bond, -CO-O-*, or -CO-NR 4 -*, * indicates a bond with -Ar, R 4 [Ar represents an alkyl group having 1 to 4 hydrogen atoms or carbon atoms, and an aromatic hydrocarbon group having 6 to 20 carbon atoms that may have one or more groups selected from hydroxyl and carboxyl groups.] Examples of resist films include the following.

[0266] A photoresist film comprising a base resin comprising repeating units as shown in formula (a1) and / or repeating units as shown in formula (a2), and repeating units of acid bonded to the polymer backbone by exposure.

[0267]

[0268] (In equations (a1) and (a2), R) A Each can be independently a hydrogen atom or a methyl group. R 1 and R 2 Each is an independent tertiary alkyl group having 4 to 6 carbon atoms. R 3 Each atom can be independently either a fluorine atom or a methyl group. m is an integer from 0 to 4. X 1 It is a single bond, a phenylene or naphthylene group, or a linker group containing 1 to 12 carbon atoms selected from at least one of ester bonds, lactone rings, phenylene, and naphthylene. X 2 (These can be single bonds, ester bonds, or amide bonds.)

[0269] Examples of corrosion-resistant materials include the following.

[0270] A corrosion resist material comprising a polymer having repeating units as shown in formula (b1) or formula (b2).

[0271]

[0272] (In equations (b1) and (b2), R) A It can be a hydrogen atom or a methyl group. X 1 It is a single bond or an ester group. X2 It is a linear, branched, or cyclic alkylene group with 1 to 12 carbon atoms or an aryl group with 6 to 10 carbon atoms. A portion of the methylene group constituting the alkylene group may be substituted with an ether group, an ester group, or a group containing an lactone ring. Furthermore, X 2 At least one hydrogen atom is replaced by a bromine atom. X 3 It is a single bond, an ether group, an ester group, or a straight-chain, branched, or cyclic alkylene group having 1 to 12 carbon atoms, wherein a portion of the methylene group constituting the alkylene group may be substituted with an ether group or an ester group. Rf 1 ~Rf 4 Each atom is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl atom, but at least one of them is a fluorine atom or a trifluoromethyl atom. Furthermore, Rf 1 and Rf 2 They can combine to form a carbonyl group. R 1 ~R 5 Each group is independently a linear, branched, or cyclic alkyl group with 1 to 12 carbon atoms, an alkenyl group with 2 to 12 carbon atoms, an alkynyl group with 2 to 12 carbon atoms, an aryl group with 6 to 20 carbon atoms, an aralkyl group with 7 to 12 carbon atoms, or an aryloxyalkyl group with 7 to 12 carbon atoms. Some or all of the hydrogen atoms in these groups may be substituted with hydroxyl, carboxyl, halogen, oxo, cyano, amide, nitro, sulopentalide, sulfonic acid, or a group containing a sulfonate. A portion of the methylene group constituting these groups may be substituted with ether, ester, carbonyl, carbonate, or sulfonate groups. Furthermore, R... 1 With R 2 They can combine with the sulfur atoms they are bonded to to form rings.

[0273] An anti-corrosion material comprising a base resin, wherein the base resin comprises a polymer containing repeating units as shown in formula (a).

[0274]

[0275] (In equation (a), R) A It can be a hydrogen atom or a methyl group. R 1 It is a hydrogen atom or an acid-instable group. R 2 It is a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or a halogen atom other than bromine. X 1 It is a single bond or a phenylene group, or a straight-chain, branched, or cyclic alkylene group having 1 to 12 carbon atoms that may contain an ester group or an lactone ring. X 2 It can be -O-, -O-CH2-, or -NH-. m is an integer from 1 to 4. u is an integer from 0 to 3. However, m + u is an integer from 1 to 4.

[0276] A photoresist composition is a photoresist composition in which acid is generated upon exposure, and its solubility in a developing solution changes due to the action of the acid. It contains a substrate component (A) whose solubility in the developer changes due to the action of acid, and a fluorinated additive component (F) that exhibits decomposition properties in alkaline developers. The aforementioned fluorinated additive component (F) contains a fluoropolymer component (F1), which has a structural unit (f1) containing a base-dissociable group and a structural unit (f2) containing a group represented by the following general formula (f2-r-1).

[0277]

[0278] [In equation (f2-r-1), Rf] 21 Each group can be independently a hydrogen atom, alkyl group, alkoxy group, hydroxy group, hydroxyalkyl group, or cyano group. n" is an integer from 0 to 2. * represents a bonding bond.

[0279] The above structural unit (f1) includes the structural unit shown in the following general formula (f1-1) or the structural unit shown in the following general formula (f1-2).

[0280]

[0281] In formulas (f1-1) and (f1-2), R is independently a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, or a haloalkyl group with 1 to 5 carbon atoms. X is a divalent linker without an acid-dissociating site. A aryl It is a divalent aromatic cyclic group that can have substituents. X 01 It is a single bond or a divalent linker. R 2 Each is an organic group containing a fluorine atom.

[0282] Examples of coatings, coating solutions, and coating compositions include the following.

[0283] A coating comprising a network of metal oxygen-hydroxyl groups having organic ligands via metal carbon bonds and / or metal carboxylic acid ester bonds.

[0284] Compositions based on inorganic oxygen / hydroxyl groups.

[0285] A coating solution comprising: an organic solvent; and a first organometallic composition, wherein the composition is derived by formula R. z SnO (2-(z / 2)-(x / 2)) (OH) x (Here, 0 < z ≤ 2 and 0 < (z + x) ≤ 4), Equation R' n SnX 4-n(Here, n = 1 or 2) or a mixture thereof, where R and R' are independently hydrocarbon groups having 1 to 31 carbon atoms, and X is a ligand having a hydrolytic bond to Sn or a combination thereof; and a hydrolytic metal compound, which is expressed by the formula MX' v (Here, M is a metal selected from groups 2 to 16 of the periodic table, v is a number from 2 to 6, and X' is a ligand of an MX bond with hydrolytic properties or a combination thereof.)

[0286] A coating solution comprising an organic solvent and the formula RSnO (3 / 2-x / 2) (OH) x The coating solution of the first organometallic compound shown in the formula (where 0 < x < 3) contains about 0.0025 M to about 1.5 M of tin, and R is an alkyl or cycloalkyl group having 3 to 31 carbon atoms, wherein the alkyl or cycloalkyl group is bonded to tin on a secondary or tertiary carbon atom.

[0287] An inorganic pattern-forming precursor aqueous solution comprising a mixture of water and a radiation-sensitive ligand comprising a metal low oxide cation, a polyatomic inorganic anion, and a peroxide group.

[0288] Irradiation by light or electron beams is performed, for example, through a mask (photomask) used to form a prescribed pattern. There are no particular limitations on the wavelength of the light. The lower film of the present invention is suitable for use in EB (electron beam) or EUV (extreme ultraviolet: 13.5 nm) irradiation, but is more preferably used in EUV (extreme ultraviolet) exposure.

[0289] There are no particular restrictions on the irradiation energy for EB and the exposure amount for EUV.

[0290] It can be baked after exposure to light or electron beams and before development (PEB: Post Exposure Bake).

[0291] There are no particular limitations on the baking temperature, but it is preferably 60°C to 150°C, more preferably 70°C to 120°C, and particularly preferably 75°C to 110°C.

[0292] There are no particular restrictions on the baking time, but it is preferred to be 1 second to 10 minutes, more preferably 10 seconds to 5 minutes, and particularly preferably 30 seconds to 3 minutes.

[0293] In the development process, an alkaline developer is used, for example.

[0294] Examples of developing temperatures include 5°C to 50°C.

[0295] Examples of development times include 10 seconds to 300 seconds.

[0296] As an alkaline developer, aqueous solutions of inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and 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, alkanolamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, and cyclic amines such as pyrrole and piperidine can be used. Furthermore, an appropriate amount of surfactants such as isopropanol or nonionic surfactants can be added to the above-mentioned alkaline aqueous solutions. Among these, aqueous solutions of quaternary ammonium salts are preferred, and aqueous solutions of tetramethylammonium hydroxide and choline are more preferred. Furthermore, surfactants can be added to these developers. Alternatively, organic solvents such as butyl acetate can be used instead of an alkaline developer to develop the portion of the photoresist whose alkaline dissolution rate has not been improved.

[0297] There are no particular restrictions on the type of resist pattern that can be formed; it can be a line pattern or a hole pattern.

[0298] When the resist pattern is a line pattern, there is no particular limitation on the line width, and examples include 30nm to 200nm.

[0299] When the resist pattern is a hole pattern, the diameter of the hole can be, for example, 30 nm to 200 nm.

[0300] Next, the underlying film is etched using the formed resist pattern as a mask. Etching can be dry etching or wet etching, but dry etching is preferred.

[0301] After step 4, a step to remove the resist pattern may be included.

[0302] The removal of the resist pattern is performed, for example, by etching. Etching can be dry etching or wet etching.

[0303] The removal of the resist pattern is usually performed before the fifth step.

[0304] <Process 5 and Process II>

[0305] The fifth step is to form a self-assembled film on the patterned lower film.

[0306] Step II is the process of forming a self-assembled membrane on the lower membrane.

[0307] Self-assembling membranes can be formed, for example, by coating a self-assembling membrane forming composition and then drying it.

[0308] Self-assembled membranes are, for example, membranes containing block copolymers.

[0309] The thickness of the self-assembled membrane is not particularly limited, but it is preferably 10 nm to 100 nm, more preferably 30 nm to 80 nm, and particularly preferably 40 nm to 60 nm.

[0310] <<Composition for Self-Assembly Film Formation>>

[0311] The composition for self-assembling film formation contains, for example, block copolymers.

[0312] Compositions for self-assembling film formation typically contain solvents.

[0313] The solid content of the self-assembling film-forming composition can be 0.1–10% by mass, 0.1–5% by mass, or 0.1–3% by mass. The solid content is the proportion remaining after removing the solvent from the film-forming composition.

[0314] The block copolymer can be made to account for 30-100% by mass, 50-100% by mass, 50-90% by mass, or 50-80% by mass in the solid component.

[0315] The block copolymer may contain two or more types of blocks. Furthermore, the number of blocks present in the block copolymer may be two or more.

[0316] <<<Block Copolymer>>>

[0317] As block polymers, they can be composed of combinations such as AB, ABAB, ABA, and ABC.

[0318] One method for synthesizing block copolymers includes living radical polymerization and living cationic polymerization, where the polymerization process consists only of initiation and growth reactions, without side reactions that deactivate the growth ends. The growth ends can maintain their growth activity throughout the polymerization reaction. Polymers (PA) with uniform length are obtained without chain transfer. By adding different monomers (mb), the growth ends of the polymer (PA) can be utilized to polymerize the monomers (mb) and form block copolymers (AB).

[0319] For example, when the block types are PA and PB, the molar ratio of polymer chain (PA) to polymer chain (PB) can be 1:9 to 9:1, preferably 3:7 to 7:3.

[0320] The volume ratio of the block copolymer is, for example, 30:70 to 70:30.

[0321] Homopolymers PA or PB are polymers of polymeric compounds having at least one reactive group (vinyl or an organic group containing vinyl) capable of free radical polymerization.

[0322] The weight-average molecular weight (Mw) of the block copolymer is preferably 1,000 to 100,000 or 5,000 to 100,000. If it is 1,000 or more, the coating properties to the substrate are excellent, and if it is 100,000 or less, the solubility in the solvent is excellent.

[0323] The polydispersity (Mw / Mn) of the block copolymer is preferably 1.00 to 1.50, more preferably 1.00 to 1.20.

[0324] The block copolymers used in this invention can be made from known materials.

[0325] As a specific example of a block copolymer, for instance, when silicon-containing polymer chains are combined with non-silicon-containing polymer chains, it is preferable to have a large difference in dry etching rates.

[0326] Examples of silicon-containing polymer chains include, for example, silylated polystyrene derivatives. Examples of silylated polystyrene derivatives include, for example, polysilanes (e.g., polydihexylsilane), polysiloxanes (e.g., polydimethylsiloxane), poly(trimethylsilylstyrene), poly(pentamethyldimethylsilylstyrene), etc.

[0327] In particular, the above-mentioned silylated polystyrene derivatives are preferably poly(4-trimethylsilylstyrene) or poly(4-pentamethyldimethylsilylstyrene) with a substituent at the 4 position.

[0328] Preferred examples of block copolymers are block copolymers obtained by combining a silicon-free polymer with styrene as a structural unit that can be replaced by an organic group or a silicon-free polymer with a structure derived from lactide as a structural unit with a silicon-containing polymer with styrene as a structural unit that is replaced by a silicon-containing group.

[0329] Among them, combinations of silylated polystyrene derivatives and polystyrene derivatives, or combinations of silylated polystyrene derivatives and polylactide, are preferred.

[0330] Among them, a combination of a silylated polystyrene derivative having a substituent at the 4-position and a polystyrene derivative having a substituent at the 4-position, or a combination of a silylated polystyrene derivative having a substituent at the 4-position and polylactide is preferred.

[0331] More preferred examples of block copolymers include combinations of poly(trimethylsilylstyrene) and polyoxymethylene styrene, combinations of polystyrene and poly(trimethylsilylstyrene), and combinations of poly(trimethylsilylstyrene) and poly(D,L-lactide).

[0332] More preferred specific examples of block copolymers include combinations of poly(4-trimethylsilylstyrene) and poly(4-methoxystyrene), combinations of polystyrene and poly(4-trimethylsilylstyrene), and combinations of poly(4-trimethylsilylstyrene) and poly(D,L-lactide).

[0333] Specific examples of block copolymers that are the most preferred choices include poly(4-methoxystyrene) / poly(4-trimethylsilylstyrene) block copolymers and polystyrene / poly(4-trimethylsilylstyrene) block copolymers.

[0334] All disclosures contained in WO2018 / 135456 are incorporated herein by reference.

[0335] Furthermore, the block copolymers mentioned above are block copolymers obtained by combining a silicon-free polymer with a silicon-containing polymer whose structural units are styrene replaced by silicon-containing groups. The silicon-free polymers may be block copolymers containing the unit structures shown in formula (1-1c) or formula (1-2c).

[0336]

[0337] (In equation (1-1c) or equation (1-2c), R) 1 and R 2 Each independently represents a hydrogen atom, a halogen atom, and an alkyl group with 1 to 10 carbon atoms; R 3 ~R 5 Each group independently represents a hydrogen atom, hydroxyl group, halogen atom, alkyl group with 1 to 10 carbon atoms, alkoxy group with 1 to 10 carbon atoms, cyano group, amino group, amide group, or carbonyl group.

[0338] The aforementioned silicon-containing groups may contain one silicon atom.

[0339] The aforementioned silicon-containing polymers may contain the unit structure shown in formula (2c).

[0340]

[0341] (In equation (2c), R) 6 ~R 8 Each can independently represent an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 40 carbon atoms.

[0342] Furthermore, as the aforementioned block copolymer, a block copolymer comprising [BCP11] to [BCP14] as described in Japanese Patent Application Publication No. 2019-507815 may be used. All disclosures described in Japanese Patent Application Publication No. 2019-507815 are incorporated herein by reference.

[0343] [BCP11] A block copolymer comprising 5-vinylbenzo[d][1,3]m-dioxane.

[0344] [BCP12] According to the block copolymer of [BCP11], the block copolymer further comprises silicon-containing blocks.

[0345] [BCP13] According to the block copolymer described in [BCP12], the block copolymer further comprises pentamethyldimethylsilylstyrene.

[0346] [BCP14] According to the block copolymer described in [BCP13], the block copolymer is poly(5-vinylbenzo[d][1,3]m-dioxane)-b-poly(pentamethyldimethylsilylstyrene).

[0347] The synthesis of poly(5-vinylbenzo[d][1,3]m-dioxane-block-4-pentamethyldimethylsilylstyrene) described above is shown in the following figure 1.

[0348]

[0349] Diagram 1

[0350] Me represents methyl.

[0351] Preferably, the aforementioned silicon-containing polymer or silicon-containing block is poly(4-trimethylsilylstyrene) derived from 4-trimethylsilylstyrene. Preferably, the aforementioned silicon-containing polymer or silicon-containing block is poly(pentamethyldimethylsilylstyrene) derived from pentamethyldimethylstyrene. An aryl group having 6 to 40 carbon atoms refers to a monocyclic or polycyclic aromatic hydrocarbon with 6 to 40 carbon atoms, and specific examples include phenyl, naphthyl, or anthracene.

[0352] All disclosures contained in brochure WO2020 / 017494 are incorporated herein by reference.

[0353] In addition, block copolymers formed from combinations of the monomers described below can be used: styrene, methyl methacrylate, dimethylsiloxane, propylene oxide, ethylene oxide, vinylpyridine, vinylnaphthalene, D,L-lactide, methoxystyrene, methylenedioxystyrene, trimethylsilylstyrene, and pentamethyldisilylstyrene.

[0354] Useful block copolymers contain at least two blocks, which can be diblock, triblock, tetrablock, etc. copolymers with different blocks, and each block can be a homopolymer, or a random or alternating copolymer.

[0355] Typical block copolymers include polystyrene-b-polyvinylpyridine, polystyrene-b-polybutadiene, polystyrene-b-polyisoprene, polystyrene-b-polymethyl methacrylate, polystyrene-b-polyalkenyl aromatic, polyisoprene-b-polyethylene oxide, polystyrene-b-poly(ethylene-propylene), polyethylene oxide-b-polycaprolactone, polybutadiene-b-polyethylene oxide, polystyrene-b-poly(tert-butyl methacrylate), polymethyl methacrylate-b-poly(tert-butyl methacrylate), polyethylene oxide-b-polypropylene oxide, and polystyrene-b-polytetrahydrofuran. The block copolymers include styrene-b-polyisoprene-b-polyethylene oxide, poly(styrene-b-dimethylsiloxane), poly(methyl methacrylate-b-dimethylsiloxane), poly((methyl methacrylate-r-styrene)-b-polymethyl methacrylate, poly((methyl methacrylate-r-styrene)-b-polystyrene, poly(p-hydroxystyrene-r-styrene)-b-polymethyl methacrylate, poly(p-hydroxystyrene-r-styrene)-b-polyethylene oxide, polyisoprene-b-polystyrene-b-polyferrocene, or combinations comprising at least one of the above block copolymers.

[0356] In addition, block copolymers formed from combinations of the organic polymers described below and / or metal-containing polymers are also exemplified.

[0357] As typical organic polymers, they include poly(9,9-bis(6'-N,N,N-trimethylammonium)-hexyl)-fluorenephenylene (PEP), poly(4-vinylpyridine) (4PVP), hydroxypropyl methylcellulose (HPMC), polyethylene glycol (PEG), poly(ethylene oxide)-poly(propylene oxide) diblock or multiblock copolymers, polyvinyl alcohol (PVA), poly(ethylene-vinyl alcohol) (PEVA), polyacrylic acid (PAA), polylactic acid (PLA), and poly(ethyl... (e.g., azoline), poly(alkyl acrylate), polyacrylamide, poly(N-alkylacrylamide), poly(N,N-dialkylacrylamide), polypropylene glycol (PPG), polypropylene oxide (PPO), partially or fully hydrogenated poly(vinyl alcohol), dextran, polystyrene (PS), polyethylene (PE), polypropylene (PP), polyisoprene (PI), polychloroprene (CR), polyvinyl ether (PVE), polyvinyl acetate (PVA), polyvinyl chloride (PVC), polyurethane (PU), polyacrylate, polymethacrylate, oligosaccharides or polysaccharides, but not limited to these.)

[0358] As a metal-containing polymer, it includes, but is not limited to, polymers containing silicon [e.g., polydimethylsiloxane (PDMS), silsesquioxane cage (POSS), or poly(trimethylsilylstyrene) (PTMSS)] or polymers containing silicon and iron [e.g., poly(ferrocene dimethylsilane) (PFS)].

[0359] Typical block copolymers (copolymers) include, but are not limited to, diblock copolymers [e.g., polystyrene-b-polydimethylsiloxane (PS-PDMS), poly(2-vinylpropylene)-b-polydimethylsiloxane (P2VP-PDMS), polystyrene-b-poly(ferrocene dimethylsilane) (PS-PFS) or polystyrene-b-polyDL lactic acid (PS-PLA)] or triblock copolymers [e.g., polystyrene-b-poly(ferrocene dimethylsilane)-b-poly(2-vinylpyridine) (PS-PFS-P2VP), polyisoprene-b-polystyrene-b-poly(ferrocene dimethylsilane) (PI-PS-PFS) or polystyrene-b-poly(ferrocene dimethylsilane)-b-polystyrene (PS-PTMSS-PS)]. In one embodiment, the PS-PTMSS-PS block copolymer comprises a poly(trimethylsilylstyrene) polymer block consisting of two chains of PTMSS linked by linkers comprising four styrene units. Furthermore, modified versions of block copolymers, such as those disclosed in U.S. Patent Application Publication No. 2012 / 0046415, are also contemplated.

[0360] Other examples of block copolymers include, for instance, block copolymers obtained by combining a polymer with styrene or a derivative thereof as structural units with a polymer with (meth)acrylate as structural units; block copolymers obtained by combining a polymer with styrene or a derivative thereof as structural units with a polymer with siloxane or a derivative thereof as structural units; and block copolymers obtained by combining a polymer with olefin oxide as structural units with a polymer with (meth)acrylate as structural units. It should be noted that "(meth)acrylate" refers to one or both of acrylates with a hydrogen atom bonded at the α-position and methacrylates with a methyl group bonded at the α-position.

[0361] Examples of (meth)acrylates include substances in which alkyl, hydroxyalkyl, or other substituents are bonded to the carbon atoms of (meth)acrylic acid. Examples of alkyl groups used as substituents include straight-chain, branched, or cyclic alkyl groups having 1 to 10 carbon atoms. Specifically, examples of (meth)acrylates include methyl methacrylate, ethyl methacrylate, propyl methacrylate, cyclohexyl methacrylate, octyl methacrylate, nonyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, benzyl methacrylate, anthracene methacrylate, glycidyl methacrylate, 3,4-epoxycyclohexylmethane, and propyltrimethoxysilane methacrylate.

[0362] Examples of styrene derivatives include, for example, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-tert-butylstyrene, 4-n-octylstyrene, 2,4,6-trimethylstyrene, 4-methoxystyrene, 4-tert-butoxystyrene, 4-hydroxystyrene, 4-nitrostyrene, 3-nitrostyrene, 4-chlorostyrene, 4-fluorostyrene, 4-acetoxyvinylstyrene, vinylcyclohexane, 4-vinylbenzyl chloride, 1-vinylnaphthalene, 4-vinylbiphenyl, 1-vinyl-2-pyrrolidone, 9-vinylanthracene, vinylpyridine, etc.

[0363] Examples of siloxane derivatives include dimethylsiloxane, diethylsiloxane, diphenylsiloxane, and methylphenylsiloxane.

[0364] Examples of olefin oxides include ethylene oxide, propylene oxide, isopropylene oxide, and butene oxide.

[0365] Examples of such block copolymers include polystyrene / poly(methyl methacrylate) block copolymers, styrene-polyethyl methacrylate block copolymers, styrene-(poly-tert-butyl methacrylate) block copolymers, styrene-polymethyl methacrylate block copolymers, styrene-polyethyl methacrylate block copolymers, styrene-(poly-tert-butyl methacrylate) block copolymers, and styrene-polyacrylate block copolymers.

[0366] All disclosures in brochure WO2022 / 039187 are cited in this specification.

[0367] <<<Solvent>>>

[0368] Examples of solvents used as solvents in compositions for self-assembling film formation include the following organic solvents.

[0369] aliphatic hydrocarbon solvents such as n-pentane, isopentane, n-hexane, isohexane, n-heptane, isoheptane, 2,2,4-trimethylpentane, n-octane, isooctane, cyclohexane, and methylcyclohexane. Aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propylbenzene, isopropylbenzene, diethylbenzene, isobutylbenzene, triethylbenzene, di-isopropylbenzene, n-pentylnaphthalene, and trimethylbenzene. Methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, 2-methylbutanol, sec-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, heptanol-3, n-octanol, 2-ethylhexanol, sec-octanol, n-nonanol, 2,6-dimethylheptanol-4, n-decanol, sec-undecyl alcohol, trimethylnonanol, sec-tetradecaneol, sec-heptadecanol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, phenylmethylmethanol, diacetone alcohol, cresol, and other monohydric alcohol solvents. Polyol solvents such as ethylene glycol, propylene glycol, 1,3-butanediol, pentanediol-2,4, 2-methylpentanediol-2,4, hexanediol-2,5, heptaethylenediol-2,4, 2-ethylhexanediol-1,3, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, and glycerol. Ketone solvents such as acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-isobutyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-isobutyl ketone, trimethylnonanone, cyclohexanone, methylcyclohexanone, 2,4-pentanedione, acetone-based acetone, diacetone alcohol, acetophenone, and ketone. Ethyl ether, isopropyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, di... Alkane, dimethyl di Alkane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-n-hexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol di-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytriethylene glycol, tetraethylene glycol di-n-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, and other ether-based solvents. Diethyl carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, acetic acid Diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, ethylene glycol diacetate, methoxytriethylene glycol acetate, ethyl propionate, n-butyl propionate, isoamyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-pentyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate, etc., ester solvents. Nitrogen-containing solvents such as N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropionic acid, and N-methylpyrrolidone Sulfur-containing solvents such as dimethyl sulfide, ethyl sulfide, thiophene, tetrahydrothiophene, dimethyl sulfoxide, sulfolane, and 1,3-propane sulpholactone In particular, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monopropyl ether acetate are preferred in terms of the stability of the composition in solution storage.

[0370] Furthermore, the solvent contained in the composition for forming a self-assembled film can be a combination of a low-boiling-point solvent (A) with a boiling point of less than 160°C and a high-boiling-point solvent (B) with a boiling point of more than 170°C as described in WO2018 / 135456.

[0371] As a low-boiling-point solvent (A) with a boiling point below 160°C, propylene glycol monomethyl ether acetate (boiling point: 146°C), n-butyl acetate (boiling point: 126°C), and methyl isobutyl ketone (boiling point: 116°C) are preferred, for example.

[0372] As a high-boiling-point solvent (B) with a boiling point of 170°C or higher, preferred examples include, for instance, N-methylpyrrolidone (boiling point: 204°C), diethylene glycol monomethyl ether (boiling point: 193°C), N,N-dimethylisobutylamide (boiling point: 175°C), 3-methoxy-N,N-dimethylpropaneamide (boiling point: 215°C), and γ-butyrolactone (boiling point: 204°C).

[0373] Low-boiling-point solvent (A) and high-boiling-point solvent (B) can also be selected and mixed together for use.

[0374] As a preferred embodiment, the high-boiling-point solvent (B) comprises 0.3 to 2.0% by weight relative to the total solvent contained in the above composition. Most preferably, it comprises 0.5 to 1.5% by weight of the high-boiling-point solvent (B).

[0375] All disclosures in WO2018 / 135456 are cited in this instruction manual.

[0376] <<Phase Separation of Self-Assembled Membranes>>

[0377] Phase separation of self-assembled membranes (e.g., block copolymer membranes) can be achieved through treatments that induce rearrangement of the self-assembled membranes, such as ultrasonic treatment, solvent treatment, or thermal annealing. In many applications, it is desirable to achieve phase separation of self-assembled membranes simply by heating or so-called thermal annealing.

[0378] Hot annealing can be carried out in the atmosphere or in an inert gas, under normal pressure, reduced pressure or increased pressure.

[0379] There are no particular restrictions on the conditions for hot annealing, but it is preferably 180°C to 300°C under atmospheric conditions, more preferably 210°C to 280°C, and particularly preferably 230°C to 270°C.

[0380] There is no particular limitation on the processing time, but it is usually 1 to 30 minutes, preferably 3 to 10 minutes.

[0381] Phase separation of the self-assembled film forms structural domains that are substantially perpendicular to the substrate or the surface of the underlying film. The morphology of these structural domains can be, for example, layered, spherical, or cylindrical. The spacing between these structural domains is, for example, 50 nm or less.

[0382] <<Patterning of Self-Assembled Films>>

[0383] By selectively removing a portion of the phase-separated self-assembled membrane, a pattern corresponding to the morphology of the structural domain is obtained.

[0384] Examples of methods for selectively removing a portion of a phase-separated self-assembled membrane include, for instance, oxygen plasma treatment of the phase-separated self-assembled membrane and hydrogen plasma treatment.

[0385] <Step 6>

[0386] The sixth step is to form a brush layer in the gaps between the patterns on the patterned lower film.

[0387] It should be noted that the sixth step is the step performed between the fourth and fifth steps.

[0388] There are no particular limitations on the method for forming the brush layer; for example, a method of coating a composition for forming the brush layer and then drying it.

[0389] <<Composition for Brush Layer Forming>>

[0390] The composition for forming a brush layer contains, for example, a brush polymer and a solvent.

[0391] Compositions for forming brush layers are, for example, compositions comprising polymer chains capable of directly bonding to the surface of a substrate. A film or layer formed by brushing polymer chains on a substrate is sometimes referred to as a brush layer.

[0392] The composition for forming a brush layer is, for example, a composition for forming a lower layer film for forming a lower layer film containing a block copolymer layer.

[0393] Furthermore, the film formed by the brush layer forming composition can, for example, function as a guide to control the generation location of the polymer phase formed through self-assembly. For instance, the film formed by the brush layer forming composition can be the sidewall of a recess in a grapho-epitaxy having an uneven structure for forming microphase separation patterns in the recesses. Additionally, for example, the film formed by the brush layer forming composition can be a chemical-epitaxy formed on the underlayer of a self-assembly material and whose formation location of the microphase separation pattern is controlled based on the difference in surface energy.

[0394] <<<Brush-type polymer>>>

[0395] As a brush polymer, there are no particular restrictions as long as it is used to form the underlying film.

[0396] As an example of a brush-type polymer, one could cite the polymer contained in a neutral, wettable substrate as described in Japanese Patent Application Publication No. 2011-515537. Examples of such polymers include, for instance, the random copolymer described in claim 15 of Japanese Patent Application Publication No. 2011-515537, and the blend of multiple grafted homopolymers described in claim 16. The contents of Japanese Patent Application Publication No. 2011-515537 are incorporated herein by reference to the full extent that they are explicitly stated.

[0397] Another example of a brush-type polymer is the random copolymer described in Japanese Patent Application Publication No. 2011-518652. One example of the random copolymer described in Japanese Patent Application Publication No. 2011-518652 is the photocrosslinkable random PS-r-PMMA described in paragraph

[0028] . The contents of Japanese Patent Application Publication No. 2011-518652 are incorporated herein by reference to the full extent that they are explicitly stated.

[0398] As another example of a brush-type polymer, one could cite, for instance, a resin in which 20 mol% to 80 mol% of the overall structural unit is derived from a monomer containing an aromatic ring. Such a resin is, for example, the resin component contained in the base agent described in International Publication No. 2012 / 036121. The contents of International Publication No. 2012 / 036121 are incorporated herein by reference to the entirety of this specification.

[0399] As another example of a brush-type polymer, one can cite, for example, the random copolymer described in claim 1 of Japanese Patent Application Publication No. 2013-166934. The contents of Japanese Patent Application Publication No. 2013-166934 are incorporated herein by reference to the full extent that they are explicitly stated.

[0400] Another example of a brush-type polymer is a polymer having a unit structure containing 0.2 mol% or more of a polycyclic aromatic vinyl compound relative to the total unit structure. Examples of such polymers include, for instance, the polymer contained in the lower film-forming composition described in International Publication No. 2014 / 097993. The contents of International Publication No. 2014 / 097993 are incorporated herein by reference to the entirety of the description.

[0401] As another example of a brush-type polymer, one can cite, for example, the polymer contained in the brush backfill composition disclosed in Japanese Patent Application Publication No. 2015-130496 (e.g., a poly(alkyl acrylate)) having functional groups capable of reacting with a semiconductor substrate). The contents of Japanese Patent Application Publication No. 2015-130496 are incorporated herein by reference to the full extent that they are explicitly stated.

[0402] As another example of a brush-type polymer, the addition polymer described in claim 1 of Japanese Patent Application Publication No. 2016-148024 can be cited. The contents of Japanese Patent Application Publication No. 2016-148024 are incorporated herein by reference to the full extent that they are explicitly stated.

[0403] As another example of a brush-type polymer, one could cite, for example, the polymer contained in the staple material described in claim 1 of Japanese Patent Application Publication No. 2016-528713. As another example of such a polymer, one could cite, for example, the polymer described in claim 3 of Japanese Patent Application Publication No. 2016-528713. The contents of Japanese Patent Application Publication No. 2016-528713 are incorporated herein by reference to the full extent that they are explicitly stated.

[0404] As another example of a brush-type polymer, one can cite, for example, the acid-sensitive copolymer comprising acid-degradable groups, adhesion groups, and functional groups as described in claim 1 of Japanese Patent Application Publication No. 2018-139007. The contents of Japanese Patent Application Publication No. 2018-139007 are incorporated herein by reference to the full extent that they are explicitly stated.

[0405] As another example of a brush-type polymer, the hydrophobic polymer brush precursor described in claim 1 of Japanese Patent Application Publication No. 2018-503241 is cited. The contents of Japanese Patent Application Publication No. 2018-503241 are incorporated herein by reference to the full extent that they are explicitly stated.

[0406] The brush-type polymer preferably has functional groups that can bond with the substrate.

[0407] Examples of functional groups that can bind to a substrate include hydroxyl, amino, and sulfonic acid groups.

[0408] Brush-type polymers may have functional groups at the ends of the polymer chains that can bind to the substrate, or they may have functional groups at positions other than the ends of the polymer chains.

[0409] There are no particular limitations on the method of introducing functional groups that can bind to the substrate into the end of the polymer chain. For example, in the case of addition polymers, methods using polymerization initiators and chain transfer agents that have compounds with functional groups that can bind to the substrate can be cited.

[0410] The brush-type polymer is preferably an addition polymer.

[0411] Addition polymers are obtained, for example, by polymerizing one or more free radical polymerizable monomers.

[0412] There are no particular limitations on monomers that can be polymerized on a free radical basis; examples include (meth)acrylic acid compounds and vinyl compounds containing aromatic groups.

[0413] Examples of (meth)acrylic acid compounds include, for example, (meth)acrylic acid and (meth)acrylates. Examples of (meth)acrylates include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, etc.

[0414] Examples of vinyl compounds containing aromatic groups include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-tert-butylstyrene, 4-n-octylstyrene, 2,4,6-trimethylstyrene, 4-methoxystyrene, 4-tert-butoxystyrene, 4-hydroxystyrene, 4-nitrostyrene, 3-nitrostyrene, 4-chlorostyrene, 4-fluorostyrene, 4-acetoxyvinylstyrene, vinylcyclohexane, 4-vinylbenzyl chloride, 1-vinylnaphthalene, 4-vinylbiphenyl, 1-vinyl-2-pyrrolidone, 9-vinylanthracene, vinylpyridine, etc.

[0415] <<<<Polymer (P)>>>>

[0416] The brush-type polymer is a polymer (P) containing the following structural units (A) and (B), which is preferred in terms of inducing microphase separation of block copolymers in the direction of perpendicularity to the substrate.

[0417] Structural unit (A): A structural unit derived from a (meth)acryloyl group and a functional group capable of binding to a substrate in a (meth)acrylic acid compound.

[0418] Structural unit (B): Structural unit derived from vinyl compounds containing aromatic groups.

[0419] The molar proportion of structural unit (A) relative to all structural units in polymer (P) is greater than 0% and less than 5%.

[0420] By ensuring that the molar proportion of structural unit (A) relative to all structural units in polymer (P) is greater than 0% and less than 5%, a film inducing microphase separation of the block copolymer with a perpendicular orientation to the substrate can be formed. If the molar proportion of structural unit (A) relative to all structural units in polymer (P) exceeds 5%, the arrangement of the microphase separation structure of the block copolymer is disordered, and the microphase separation structure of the block copolymer cannot be induced to be perpendicular to the substrate.

[0421] As for the polymer (P), there are no particular limitations as long as it contains structural units (A) and (B), but it is preferred to be an addition polymer obtained by polymerization of a compound having a polymerizable unsaturated group. Examples of polymerizable unsaturated groups include, for example, olefinic unsaturated groups. Examples of olefinic unsaturated groups include, for example, vinyl, allyl, propargyl, butenyl, ethynyl, phenylethynyl, maleimide, nadimide, (meth)acryloyl, etc.

[0422] The polymer (P) is, for example, a random copolymer.

[0423] The polymer (P) may contain structural units other than structural units (A) and (B).

[0424] Structural unit (A) is derived from (meth)acrylic acid compounds.

[0425] (Meth)acrylic acid compounds have (meth)acryloyl groups.

[0426] (Meth)acrylic acid compounds have functional groups that can bind to a substrate.

[0427] The term (meth)acryloyl is used to represent acryloyl and methacryloyl groups. Acryloyl refers to the group represented by CH2=CH-CO-, and methacryloyl refers to the group represented by CH2=C(CH3)-CO-.

[0428] There are no particular limitations on the functional groups that can bind to the substrate, and examples include hydroxyl, amino, and sulfonic acid groups.

[0429] The number of functional groups in structural unit (A) that can bond with the substrate can be one or more, but one is preferred.

[0430] The (meth)acryloyl group in (meth)acrylic acid compounds can be one or more, but one is preferred.

[0431] Structural unit (A) is a different structural unit from structural unit (B). Therefore, structural unit (B) does not have an aromatic ring.

[0432] The structural unit (A) in the polymer (P) can be one type or two or more types.

[0433] As a structural unit (A), it is preferable to include the structural unit (A-1) shown in the following formula (1).

[0434]

[0435] (In formula (1), X represents -O- or -NH-. Y represents a hydroxyl, amino, or sulfonic acid group. R) 1 R represents an alkylene group with 1 to 10 carbon atoms that can be replaced by a halogen atom. 2 (This indicates a hydrogen atom or a methyl group.)

[0436] As for the amino group, primary amino or secondary amino groups are preferred.

[0437] The term "primary amino group" refers to a monovalent functional group (-NH2) that has had a hydrogen atom removed from ammonia.

[0438] The term secondary amine refers to a monovalent functional group (-NHR, where R represents an organogroup) that has had a hydrogen atom removed from a primary amine. R represents, for example, an alkyl group having 1 to 6 carbon atoms.

[0439] Alkyl groups with 1 to 10 carbon atoms that can be replaced by halogen atoms can be straight-chain, branched, or cyclic.

[0440] Examples of halogen atoms include fluorine, chlorine, bromine, and iodine.

[0441] The number of halogen atoms in an alkylene group with 1 to 10 carbon atoms substituted by halogen atoms can be one or more.

[0442] As alkylene groups having 1 to 10 carbon atoms, they can be straight-chain or branched, and examples include methylene, ethylene, 1,3-propylene (trimethylene group), 1-methylethylene (1,2-propylene), 1,4-butylene, 1-ethylethylene, 1-methylpropylene, 2-methylpropylene, 1,5-pentylene, 1-methylbutylene, 2-methylbutylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene, 1-ethylpropylene, 2-ethylpropylene, 1,6-hexylene, 1,4-cyclohexylene, 1,8-octylene, 2-ethyloctylene, 1,9-nonylene, 1,10-decylene, etc.

[0443] The molar ratio of structural unit (A) to all structural units in polymer (P) is greater than 0% and less than 5%, preferably more than 0.1% and less than 5%, more preferably more than 0.3% and less than 4.5%, and particularly preferably more than 0.5% and less than 4.0%.

[0444] Examples of (meth)acrylic acid compounds include, for instance, compounds represented by the following formula (1-1).

[0445]

[0446] (In formula (1-1), X represents -O- or -NH-. Y represents a hydroxyl, amino, or sulfonic acid group. R) 1 R represents an alkylene group with 1 to 10 carbon atoms that can be replaced by a halogen atom. 2 (This indicates a hydrogen atom or a methyl group.)

[0447] Examples of (meth)acrylic acid compounds include, for example, (meth)acrylates containing hydroxyl groups, (meth)acrylates containing amino groups, (meth)acrylates containing sulfonic acid groups, (meth)acrylamides containing hydroxyl groups, and (meth)acrylamides containing sulfonic acid groups.

[0448] Examples of hydroxyl-containing (meth)acrylates include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, and 1,4-cyclohexanediethanol mono(meth)acrylate.

[0449] Examples of (meth)acrylates containing amino groups include, for example, (meth)acrylates containing primary amino groups and (meth)acrylates containing secondary amino groups.

[0450] Examples of (meth)acrylates containing a primary amino group include, for example, aminomethyl (meth)acrylate and aminoethyl (meth)acrylate.

[0451] Examples of (meth)acrylates containing a secondary amino group include, for example, tert-butylaminoethyl (meth)acrylate and tert-butylaminopropyl (meth)acrylate.

[0452] As (meth)acrylates containing sulfonic acid groups, for example, 2-sulfoethyl (meth)acrylate and 3-sulfopropyl (meth)acrylate.

[0453] Examples of (meth)acrylamides containing hydroxyl groups include N-(hydroxymethyl)acrylamide, N(2-hydroxyethyl)acrylamide, and N-(4-hydroxybutyl)acrylamide.

[0454] Structural unit (B) is derived from a vinyl compound containing an aromatic group.

[0455] The aromatic ring in a vinyl compound containing an aromatic group can be an aromatic hydrocarbon ring or an aromatic heterocycle, but an aromatic hydrocarbon ring is preferred.

[0456] Examples of aromatic hydrocarbon rings include benzene rings, naphthalene rings, and anthracene rings.

[0457] Vinyl compounds containing aromatic groups do not have functional groups that can bind to a substrate, for example.

[0458] Vinyl compounds containing aromatic groups do not have, for example, hydroxyl, amino, and sulfonic acid groups.

[0459] Structural unit (B) does not have, for example, functional groups that can bond with the substrate.

[0460] Structural unit (B) does not have, for example, hydroxyl, amino, and sulfonic acid groups.

[0461] The structural unit (B) in the polymer (P) can be one type or two or more types.

[0462] As a structural unit (B), it is preferable to include the structural unit (B-1) shown in the following formula (2).

[0463] As a structural unit (B), it is preferable to include the structural unit (B-2) shown in the following formula (3).

[0464]

[0465] (In equation (2), each of the n Y atoms independently represents a halogen atom, alkyl group, alkoxy group, alkoxycarbonyl group, or alkylthio group, and n represents an integer from 0 to 7.)

[0466] (In equation (3), R)3 ~R 5 Each can independently represent a hydrogen atom or a tert-butyl group. Wherein, R... 3 ~R 5 One or two of them represent tert-butyl.

[0467] Examples of halogen atoms in Y in formula (2) include fluorine, chlorine, bromine, and iodine atoms.

[0468] As for the alkyl group in formula (2), it is preferably an alkyl group with 1 to 15 carbon atoms, more preferably an alkyl group with 1 to 10 carbon atoms, even more preferably an alkyl group with 1 to 6 carbon atoms, and particularly preferably an alkyl group with 1 to 3 carbon atoms. The alkyl group can be straight-chain, branched, or cyclic.

[0469] As for the alkoxy group in formula (2), it is preferred to be an alkoxy group with 1 to 15 carbon atoms, more preferably an alkoxy group with 1 to 10 carbon atoms, even more preferably an alkoxy group with 1 to 6 carbon atoms, and particularly preferably an alkoxy group with 1 to 3 carbon atoms. The alkyl group in the alkoxy group can be straight-chain, branched, or cyclic.

[0470] As for the alkoxycarbonyl group in formula (2), it is preferred to be an alkoxycarbonyl group with 2 to 15 carbon atoms, more preferably an alkoxycarbonyl group with 2 to 10 carbon atoms, even more preferably an alkoxycarbonyl group with 2 to 6 carbon atoms, and particularly preferably an alkoxycarbonyl group with 2 to 3 carbon atoms. The alkyl group in the alkoxycarbonyl group can be straight-chain, branched, or cyclic.

[0471] As an alkylthio group in Y in formula (2), examples can be groups in which the -O- of the above alkoxy group is replaced with -S-.

[0472] There are no particular limitations on the molar ratio of structural unit (B) to all structural units in polymer (P), but it is preferably 80% or more and less than 100%, more preferably 90% or more and less than 100%, and particularly preferably more than 95% and less than 100%.

[0473] The molar ratio (structural unit (A): structural unit (B)) of structural unit (A): structural unit (B) in polymer (P) is not particularly limited, but is preferably 1:200 to 1:10, more preferably 1:150 to 1:20.

[0474] When the polymer (P) contains the structural unit (B-1) shown in formula (2), there is no particular limitation on the molar ratio (structural unit (A): structural unit (B-1)) of structural unit (A): structural unit (B-1) in the polymer (P), but it is preferably 1:100 to 1:5, and more preferably 1:75 to 1:10.

[0475] When the polymer (P) contains the structural unit (B-2) shown in formula (3), there is no particular limitation on the molar ratio (structural unit (A): structural unit (B-2)) of structural unit (A): structural unit (B-2) in the polymer (P), but it is preferably 1:100 to 1:5, and more preferably 1:75 to 1:10.

[0476] When the polymer (P) contains the structural unit (B-1) shown in formula (2) and the structural unit (B-2) shown in formula (3), there is no particular limitation on the molar ratio (structural unit (B-1): structural unit (B-2)) of structural unit (B-1): structural unit (B-2) in the polymer (P), but it is preferably 1.0:0.1 to 0.1:1.0, more preferably 1.0:0.5 to 0.5:1.0, and particularly preferably 1.0:0.7 to 0.7:1.0.

[0477] Examples of vinyl compounds containing aromatic groups include, for example, compounds represented by formula (2-1) and compounds represented by formula (3-1).

[0478]

[0479] (In equation (2-1), each of the n Y atoms independently represents a halogen atom, alkyl group, alkoxy group, alkoxycarbonyl group, or alkylthio group, and n represents an integer from 0 to 7.)

[0480] (In equation (3-1), R) 3 ~R 5 Each can independently represent a hydrogen atom or a tert-butyl group. Wherein, R... 3 ~R 5 One or two of them represent tert-butyl.

[0481] The weight-average molecular weight of the brush polymer, as determined by gel permeation chromatography (GPC), is not particularly limited, but when converted to polystyrene, it is, for example, 1,000 to 50,000, preferably 2,000 to 20,000.

[0482] <<<<Method for Manufacturing Brush-Type Polymers>>>>

[0483] There are no particular restrictions on the manufacturing method of brush-type polymers.

[0484] For example, in the case where the brush polymer is an addition polymer, it can be manufactured by polymerizing the monomer using conventional methods such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization. Solution polymerization is particularly preferred, in which, for example, polymerization can be carried out by adding the desired monomer to a solvent containing a polymerization initiator.

[0485] For example, in the case where the brush polymer is an addition-polymerized random copolymer, it can be manufactured by copolymerizing various monomers in a manner that is appropriate in molar ratio using conventional methods such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization.

[0486] Examples of such polymerization include free radical polymerization.

[0487] The manufacturing method of brush-type polymers can be any polymerization method other than free radical polymerization. For example, it can be a manufacturing method using ionic (anionic, cationic) addition polymerization, or a manufacturing method using condensation polymerization or addition polymerization.

[0488] The polymer (P) can be manufactured, for example, by solution polymerization of a mixture of monomers containing a (meth)acryloyl compound having a (meth)acrylyl group and a functional group capable of binding to a substrate, and a vinyl compound containing an aromatic group.

[0489] [Polymerization initiator]

[0490] Organic peroxides and diazo compounds can be used as polymerization initiators.

[0491] Examples of organic peroxides include peroxydiacyl peroxides, peroxydicarbonate peroxides, peroxyester peroxides, and peroxysulfonate peroxides.

[0492] Examples of diacetyl peroxides include, for example, diacetyl peroxide, diisobutyl peroxide, didecyl peroxide, benzoyl peroxide, and succinic acid peroxide.

[0493] Examples of peroxide dicarbonates include, for example, diisopropyl peroxide dicarbonate, di-2-ethylhexyl peroxide dicarbonate, diallyl peroxide dicarbonate, etc.

[0494] Examples of peroxide esters include tert-butyl peroxide isobutyrate, tert-butyl neodecanoate, and isopropylphenyl peroxide neodecanoate.

[0495] Examples of peroxide sulfonates include, for example, acetylcyclohexylsulfonyl peroxide.

[0496] Examples of diazo compounds include 2,2'-azobisisobutyronitrile, 4,4'-azobis(4-cyanopentaic acid), 2,2'-azobis(4-methoxy-2,4-dimethoxypentanone), and 2,2'-azobis(2-cyclopropylpropionitrile).

[0497] When it is desired to end the polymerization in a short time, a polymerization initiator with a decomposition half-life of less than 10 hours at 80°C is preferred. Benzoyl peroxide and 2,2'-azobisisobutyronitrile are preferred as such polymerization initiators, and 2,2'-azobisisobutyronitrile is more preferred.

[0498] The amount of polymerization initiator used relative to the total amount of monomer used is, for example, 0.0001 to 0.2 equivalents, preferably 0.0005 to 0.1 equivalents.

[0499] [Solvent]

[0500] As for the solvent used in the polymerization, there are no particular restrictions as long as the solvent does not participate in the polymerization reaction and is compatible with the resulting brush polymer. Examples include aromatic hydrocarbons, alicyclic hydrocarbons, aliphatic hydrocarbons, ketones, ethers, esters, amides, sulfoxides, alcohols, and polyol derivatives.

[0501] Examples of aromatic hydrocarbons include benzene, toluene, and xylene.

[0502] Examples of alicyclic hydrocarbons include cyclohexane.

[0503] Examples of aliphatic hydrocarbons include n-hexane and n-octane.

[0504] Examples of ketones include acetone, methyl ethyl ketone, and cyclohexanone.

[0505] Examples of ethers include tetrahydrofuran and dihydrofuran. Alkane, etc.

[0506] Examples of esters include ethyl acetate and butyl acetate.

[0507] Examples of amides include N,N-dimethylformamide and N,N-dimethylacetamide.

[0508] Examples of sulfoxides include, for example, dimethyl sulfoxide.

[0509] Examples of alcohols include methanol and ethanol.

[0510] Examples of polyol derivatives include ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether acetate.

[0511] They can be used individually or in combination of two or more.

[0512] There is no particular limitation on the polymerization temperature range as long as side reactions such as transfer reactions and termination reactions do not occur, and the monomer is consumed and the polymerization ends. However, it is preferred to carry out the polymerization in a temperature range above -100℃ and below the boiling point of the solvent.

[0513] Furthermore, there are no particular limitations on the concentration of the monomer relative to the solvent, which is typically 1 to 40% by mass, preferably 10 to 30% by weight.

[0514] The time for the polymerization reaction can be selected appropriately, but it is usually in the range of 2 to 50 hours.

[0515] <<<Solvent>>>

[0516] There are no particular restrictions on the solvent contained in the composition for forming the brush layer, as long as it is a solvent that dissolves the brush-type polymer.

[0517] Examples of solvents include propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monopropyl ether, methyl ethyl ketone, ethyl lactate, cyclohexanone, N,N-2-trimethylpropionamide, γ-butyrolactone, N-methyl-2-pyrrolidone, methyl 2-hydroxyisobutyrate, and ethyl 3-ethoxypropionate.

[0518] They can be used individually or in combination of two or more.

[0519] The content of the solvent in the composition for forming the brush layer is not particularly limited, for example, it is 90% by mass or more and 99.9% by mass or less.

[0520] <<<Other Ingredients>>>

[0521] The brush layer forming composition preferably does not contain a crosslinking agent. For example, by reacting a brush-type polymer with a substrate, the film obtained from the brush layer forming composition becomes a film that is insoluble in the solvent contained in a self-assembled film forming composition containing a block copolymer. Therefore, the brush layer forming composition does not need to contain a crosslinking agent.

[0522] In this invention, the term "not containing a crosslinking agent" may also include a slight presence of a crosslinking agent to the extent that its role as a crosslinking agent is not fully realized. As an option for a brush layer forming composition not containing a crosslinking agent, it is preferable that the content of the crosslinking agent in the brush layer forming composition is less than 0.1% by mass relative to the brush-type polymer, more preferably 0.01% by mass or less, and particularly preferably 0.001% by mass or less.

[0523] Examples of crosslinking agents include nitrogen-containing compounds having two to four nitrogen atoms substituted with hydroxymethyl or alkoxymethyl groups.

[0524] Examples of crosslinking agents include hexamethoxymethyl melamine, tetramethoxymethyl glycourea, tetramethoxymethyl guanidine, 1,3,4,6-tetra(methoxymethyl)glycourea, 1,3,4,6-tetra(butoxymethyl)glycourea, 1,3,4,6-tetra(hydroxymethyl)glycourea, 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetra(butoxymethyl)urea, and 1,1,3,3-tetra(methoxymethyl)urea.

[0525] The composition for forming the brush layer may contain a surfactant. The surfactant is an additive used to improve the coatability to the substrate.

[0526] As a surfactant, well-known surfactants such as nonionic surfactants and fluorinated surfactants can be used.

[0527] Examples of surfactant content in the composition for forming the brush layer include 0.1% to 5% by mass relative to the brush-type polymer.

[0528] In a composition for forming a brush layer, if the component from which the solvent has been removed is defined as a solid component, then the solid component contains a brush-type polymer and additives added as needed.

[0529] The concentration of the solid component in the composition for forming the brush layer is not particularly limited, for example, it is 0.1% to 15% by mass, preferably 0.1% to 10% by mass.

[0530] An example of a method for manufacturing a semiconductor element according to the present invention will be illustrated using figures.

[0531] Figures 1A to 1I This is a cross-sectional schematic diagram illustrating an example of a method for manufacturing a semiconductor element according to the present invention.

[0532] A lower film 2 is formed on a semiconductor substrate 1 using the lower film formation composition of the present invention. Figure 1A ).

[0533] Next, a resist film 3 is formed on the lower layer film 2. Figure 1B ).

[0534] Next, the resist film 3 is subjected to light or electron beam irradiation, followed by development to obtain a resist pattern (patterned resist film 3). Figure 1C ).

[0535] Next, the resist pattern (patterned resist film 3) is used as a mask to etch the lower film 2, forming the patterned lower film 2. Figure 1D )

[0536] Next, the resist pattern (patterned resist film 3) will be removed. Figure 1E ).

[0537] Next, a brush layer forming composition is coated on the semiconductor substrate 1 and the patterned lower layer film 2 to form a brush layer 4. Figure 1F ).

[0538] Next, a portion of the brush layer 4 is removed, forming the brush layer 4 in the gaps between the patterns of the patterned lower film 2. Figure 1G ).

[0539] Next, a self-assembled film 5 is formed on the patterned lower film 2 and brush layer 4. The self-assembled film 5 is, for example, a block copolymer film having A-blocks and B-blocks. By subjecting the self-assembled film 5 to phase separation, a microphase-separated structure having A-block domains 5a and B-block domains 5b is obtained. Figure 1H ).

[0540] By selectively removing a portion (e.g., the B-block structural domain 5b) of the microphase-separated self-assembled membrane 5, a pattern corresponding to the morphology of the microphase-separated structural domains is obtained. Figure 1I ).

[0541] Although not illustrated, as a further step, examples include processing a semiconductor substrate using a pattern corresponding to the morphology of the microphase-separated structural domains as a mask, or using a lower film 2 and a brush layer 4 with the transferred pattern as a mask.

[0542] Example

[0543] The following examples illustrate the content of the present invention in detail, but the present invention is not limited to them.

[0544] The weight-average molecular weights of the polymers shown in Synthetic Example 1 and Comparative Synthetic Example 1 in this specification are determined by gel permeation chromatography (hereinafter referred to as GPC). A GPC apparatus manufactured by Toso Corporation was used in the determination, and the determination conditions are as follows.

[0545] GPC pillars: Shodex KF803L, Shodex (registered trademark) KF802, Shodex (registered trademark) KF801 (Showa Denko Co., Ltd.)

[0546] Column temperature: 40℃

[0547] Solvent: N,N-dimethylformamide (DMF)

[0548] Flow rate: 0.6 ml / min

[0549] Standard sample: Polystyrene (manufactured by Tosoo Corporation)

[0550] <Synthesis example 1>

[0551] A solution was obtained by dissolving 2.12 g of 2-vinylnaphthalene (60% molar ratio relative to the total polymer 1), 1.09 g of 3-hydroxy-1-methacryloyloxyadamantane (20% molar ratio relative to the total polymer 1), 0.60 g of 2-hydroxyethyl methacrylate (20% molar ratio relative to the total polymer 1), and 0.19 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 1. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 8,100. The structure present in polymer 1 is shown in the following formula.

[0552]

[0553] <Synthesis example 2>

[0554] A solution was obtained by dissolving 2.13 g of 2-vinylnaphthalene (60% molar ratio relative to polymer 2), 1.09 g of 3-hydroxy-1-methacryloyloxyadamantane (20% molar ratio relative to polymer 2), 0.66 g of 2-hydroxypropyl methacrylate (20% molar ratio relative to polymer 2), and 0.12 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 2. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 7,100. The structure present in polymer 2 is shown in the following formula.

[0555]

[0556] <Synthesis Example 3>

[0557] A solution was obtained by dissolving 1.92 g of 2-vinylnaphthalene (60% molar ratio relative to polymer 3), 1.96 g of 3-hydroxy-1-methacryloyloxyadamantane (40% molar ratio relative to polymer 3), and 0.12 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 3. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 8,900. The structure present in polymer 3 is shown in the following formula.

[0558]

[0559] <Synthesis example 4>

[0560] A solution was obtained by dissolving 1.96 g of 4-tert-butylstyrene (60% molar ratio relative to polymer 4), 1.93 g of 3-hydroxy-1-methacryloyloxyadamantane (40% molar ratio relative to polymer 4), and 0.12 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to heptane, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 4. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 6,600. The structure present in polymer 4 is shown in the following formula.

[0561]

[0562] <Synthesis example 5>

[0563] A solution was obtained by dissolving 1.88 g of 2-vinylnaphthalene (55% molar ratio relative to polymer 5), 1.01 g of benzyl methacrylate (26% molar ratio relative to polymer 5), 0.99 g of 3-hydroxy-1-methacryloyloxyadamantane (19% molar ratio relative to polymer 5), and 0.12 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 5. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 7,700. The structure present in polymer 5 is shown in the following formula.

[0564]

[0565] <Synthesis Example 6>

[0566] A solution was obtained by dissolving 1.84 g of 2-vinylnaphthalene (55% molar ratio relative to polymer 6), 1.07 g of 2-phenylethyl methacrylate (26% molar ratio relative to polymer 6), 0.97 g of 3-hydroxy-1-methacryloyloxyadamantane (19% molar ratio relative to polymer 6), and 0.12 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 6. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 7,600. The structure present in polymer 6 is shown in the following formula.

[0567]

[0568] <Synthesis Example 7>

[0569] A solution was obtained by dissolving 1.92 g of 2-vinylnaphthalene (55% molar ratio relative to polymer 7), 0.95 g of phenyl methacrylate (26% molar ratio relative to polymer 7), 1.01 g of 3-hydroxy-1-methacryloyloxyadamantane (19% molar ratio relative to polymer 7), and 0.12 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 7. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 6,800. The structure present in polymer 7 is shown in the following formula.

[0570]

[0571] <Comparative Synthesis Example 1>

[0572] A solution was obtained by dissolving 2.17 g of 2-vinylnaphthalene (60% molar ratio relative to polymer 8), 1.03 g of 1-adamantyl methacrylate (20% molar ratio relative to polymer 8), 0.61 g of 2-hydroxyethyl methacrylate (20% molar ratio relative to polymer 8), and 0.19 g of 2,2'-azobisisobutyronitrile in 16.00 g of propylene glycol monomethyl ether acetate. The solution was heated and stirred at 145 °C for approximately 3 hours. The resulting reaction mixture was added dropwise to 2-propanol, and the precipitate was recovered by vacuum filtration and then dried under reduced pressure at 60 °C to recover polymer 8. The weight-average molecular weight (Mw) determined by GPC to be equivalent to polystyrene was 7,100. The structure present in polymer 8 is shown in the following formula.

[0573]

[0574] (Preparation of the composition for lower layer film formation)

[0575] (Example)

[0576] The polymers, crosslinking agents, curing catalysts, and solvents obtained in the above synthesis examples 1 to 7 and comparative synthesis example 1 were mixed in the proportions shown in Table 1 and filtered through a 0.02 μm fluororesin filter to prepare compositions for forming the lower layer of a self-assembled membrane.

[0577] The abbreviations in Tables 1 and 2 are as follows. All amounts added are expressed in parts by mass.

[0578] PL-LI: tetramethoxymethyl glycoluril (manufactured by Nippon Sectronics Co., Ltd.)

[0579] PyPTS: Pyridine p-Toluenesulfonic acid

[0580] PGMEA: Propylene glycol monomethyl ether acetate

[0581] PGME: Propylene Glycol Monomethyl Ether

[0582] [Table 1]

[0583] [Table 2]

[0584] (Dissolution test in photoresist solvent)

[0585] The lower film formation compositions for self-assembled films of Examples 1-7 and Comparative Example 1 were coated onto a silicon wafer using a spin coater. The silicon wafer was baked on a hot plate at 240°C for 60 seconds to obtain a film with a thickness of 8 nm. These lower films were immersed in a mixed solution of propylene glycol monomethyl ether (PGME) / propylene glycol monomethyl ether acetate (PGMEA) = 70 / 30 as the solvent used as the photoresist. Film thickness variations of less than 2 Å were classified as "good," and those exceeding 2 Å were classified as "poor." The results are shown in Table 3.

[0586] (Film-forming property test)

[0587] The lower film formation compositions of Examples 1-7 and Comparative Example 1 for self-assembled films were coated onto a silicon wafer using a spin coater. The silicon wafer was baked on a hot plate at 240°C for 60 seconds to obtain a film with a thickness of 8 nm. The surface roughness (Sa) of these lower films was measured using atomic force microscopy (AFM), with values ​​below 3 Å defined as "good" and values ​​above 3 Å defined as "poor". The results are shown in Table 3.

[0588] [Table 3]

[0589] (Evaluation of self-assembly on the composition for forming the lower layer of a self-assembly membrane)

[0590] The composition for forming the lower layer of the self-assembled film was spin-coated onto a silicon wafer. The silicon wafer was baked on a hot plate at 240°C for 60 seconds to obtain a lower layer film with a thickness of 8 nm. A self-assembled film (block copolymer) solution was spin-coated onto the lower layer film, and heated at 90°C for 60 seconds to form a self-assembled film. The laminated film was baked on a hot plate under N2 atmosphere at 260°C for 900 seconds to achieve self-assembly (microphase separation). The microphase separation structure was then observed using a scanning electron microscope (manufactured by Hitachi Hightech Noroges Co., Ltd., CG4100), and the vertical alignment was evaluated. Vertical alignment was defined as "good" when the pattern obtained by self-assembly was a hole shape (cylinder), and "poor" when the pattern was an alignment shape on a fingerprint (fingerprint). The results are shown in Table 4.

[0591] [Table 4]

[0592] (Observation of microphase separation structure)

[0593] Regarding the arrangement of the block copolymers, SEM images of the microphase separation structures of Examples 1-7 and Comparative Example 1 are shown below. Figures 2-8(Good vertical alignment) and Figure 9 (Poor vertical alignment)

[0594] Explanation of symbols

[0595] 1. Semiconductor substrate

[0596] 2. Lower membrane

[0597] 3. Resist film

[0598] 4. Brush layer

[0599] 5 Self-assembling membrane

[0600] 5a A block structure domain

[0601] The structural domain of the 5b B block.

Claims

1. A composition for forming a lower layer film, which is a composition for forming a lower layer film of a self-assembled membrane. It contains polymers, The polymer has a unit structure (A) having an alicyclic hydrocarbon group with a reactive group.

2. The composition for forming a lower film according to claim 1, wherein the unit structure (A) is a unit structure represented by the following formula (A-1), In equation (A-1), R 1 Indicates a hydrogen atom or a methyl group; X 1 Indicates a single bond, ester group, or amide group; Y 1 It represents a single bond or an alkylene group with 1 to 6 carbon atoms; Cy represents an alicyclic hydrocarbon group with a reactive group.

3. The composition for forming a lower film according to claim 1, wherein the polymer further has a unit structure represented by the following formula (B-1), In equation (B-1), R 11 Indicates a hydrogen atom or a methyl group; Ar 11 This indicates an aromatic group that can be replaced.

4. The composition for forming a lower film according to claim 3, wherein in formula (B-1), Ar 11 This indicates naphthalene, anthracene, phenanthrene, pyrene, benzo[9,10]phenanthrene, etc., which can be substituted. , tetraphenyl, biphenylene, fluorene or carbazole, or benzene having one or more substituents having 1 to 6 carbon atoms as hydrocarbon groups.

5. The composition for forming a lower film according to claim 1, wherein the polymer further has a unit structure (C) having a monocyclic aromatic structure.

6. The composition for forming a lower film according to claim 5, wherein the unit structure (C) is a unit structure represented by the following formula (C-1), In equation (C-1), R 21 Indicates a hydrogen atom or a methyl group; X 21 Indicates an ester or amide group; Y 21 Indicates a single bond or an alkylene group having 1 to 6 carbon atoms; Z 21 Indicates a single bond or ether group; Ar 21 Indicates that benzene, naphthalene, or anthracene can be substituted; R 22 Represents a halogen atom or an organogroup with 1 to 10 carbon atoms that can be substituted; n represents an integer from 0 to 5; in R 22 When there are two or more R's 22 They can be the same or different.

7. The composition for forming a lower film according to claim 1, wherein the polymer further has a unit structure (D) having a hydrocarbon group having a reactive group, but excluding alicyclic hydrocarbon groups.

8. The composition for forming a lower film according to claim 7, wherein the unit structure (D) is a unit structure represented by the following formula (D-1), In equation (D-1), R 31 Indicates a hydrogen atom or a methyl group; X 31 Indicates an ester or amide group; R 32 It refers to a hydrocarbon group with 1 to 12 carbon atoms that has a reactive group, except for alicyclic hydrocarbon groups.

9. The composition for forming a lower film according to claim 1, wherein the molar ratio of the unit structure (A) to all unit structures of the polymer is less than 60 moles.

10. The composition for forming a lower layer film according to claim 3, wherein the molar ratio of the unit structure (B-1) to all unit structures of the polymer is 45 mol% to 80 mol%.

11. The composition for forming a lower film according to claim 1, further comprising a crosslinking agent, wherein the content of the crosslinking agent is 20% to 50% by mass of the polymer.

12. The composition for forming a lower layer film according to claim 1, wherein the self-assembled film is a film comprising a block copolymer.

13. The composition for forming a lower layer film according to claim 1 is a composition for forming a lower layer film, wherein the lower layer film is used as a lower layer film of the self-assembled film after being used as a lower layer film of the photoresist film and in photolithography using either a photoresist film or an electron beam photoresist film and the self-assembled film.

14. A lower layer film, which is a sintered product of a coated film of the lower layer film forming composition according to any one of claims 1 to 13.

15. The lower layer film according to claim 14, wherein the thickness of the lower layer film is less than 10 nm.

16. A method for manufacturing a semiconductor device, comprising the following steps: The process of forming a lower layer film on a semiconductor substrate using the composition for forming a lower layer film according to any one of claims 1 to 13; and The process of forming a self-assembling membrane on the lower membrane.

17. The method for manufacturing a semiconductor device according to claim 16, wherein in the step of forming the self-assembled film, the self-assembled film is formed on the patterned underlying film. The method for manufacturing the semiconductor device further includes the following steps: The process of forming either a photoresist film or an electron beam resist film on the lower layer film; The process of irradiating the resist film with light or an electron beam, followed by developing the resist film to obtain a resist pattern; and The process of etching the underlying film using the resist pattern as a mask to form the patterned underlying film.

18. The method of manufacturing a semiconductor element according to claim 17, further comprising, between the step of forming the patterned lower film and the step of forming the self-assembled film, a step of forming a brush layer in the gaps of the patterned lower film.

19. The method for manufacturing a semiconductor element according to claim 16, wherein the self-assembled film is a film comprising a block copolymer.

20. The method of manufacturing a semiconductor device according to claim 17, further comprising, after the step of forming the patterned lower film, a step of removing the resist pattern.

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