# US 11,440,985 B2 · Underlayer film-forming composition for use in forming a microphase-separated pattern > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,440,985 B2 - Document ID: US11440985B2 - Status: Granted - Kind: B2 - Application number: 16/477,910 - Filed: 2018-01-16 - Published: 2019-11-28 - Granted: 2022-09-13 - Earliest claimed: 2017-01-19 - Assignees: Nissan Chemical Corporation - Applicants: Nissan Chemical Corporation - Inventors: Ryuta Mizuochi; Yasunobu Someya; Hiroyuki Wakayama; Rikimaru Sakamoto - Web page: https://patentgrep.com/patent/US11440985B2 ## CPC - C08F 212/12: Monomers containing a branched unsaturated aliphatic radical or a ring substituted by an alkyl radical - C08F 220/1807: {C7-(meth)acrylate, e.g. heptyl (meth)acrylate or benzyl (meth)acrylate} - C08F 222/402: {Alkyl substituted imides} - C09D 4/00: Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond {; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16} - C09D 5/00: Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced {(electrically insulating plastics, resins or waxes H01B3/30)}; Filling pastes - C09D 125/08: Copolymers of styrene (C09D129/08, C09D135/06, C09D155/02 take precedence) - C09D 133/10: Homopolymers or copolymers of methacrylic acid esters - C09D 153/00: Coating compositions based on block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Coating compositions based on derivatives of such polymers - H10P 76/00: Manufacture or treatment of masks on semiconductor bodies, e.g. by lithography or photolithography - C08F 220/18: with acrylic or methacrylic acids - C08L 25/16: Homopolymers or copolymers of alkyl-substituted styrenes - C08L 33/10: Homopolymers or copolymers of methacrylic acid esters - C09D 125/16: Homopolymers or copolymers of alkyl-substituted styrenes - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) ## Abstract An underlayer film-forming composition which exhibits excellent solvent resistance, and which is capable of orthogonally inducing, with respect to a substrate, a microphase separation structure in a layer formed on the substrate, said layer including a block copolymer. The underlayer film-forming composition includes a copolymer which includes: (A) unit structures derived from styrene compounds including tert-butyl groups; (B) unit structures, other than those in (A) above, which are derived from aromatic-containing vinyl compounds which do not include hydroxy groups; (C) unit structures derived from compounds which include (meth)acryloyl groups, and do not include hydroxy groups; and (D) unit structures derived from compounds including crosslink-forming groups. The copolymerization ratios with respect to the whole copolymer are: (A) 25-90 mol %; (B) 0-65 mol %; (C) 0-65 mol %; and (D) 10-20 mol %. Unit structures including aromatics account for 81-90 mol % of (A)+(B)+(C). ## Claims ### Claim 1 An underlayer film-forming composition for use in causing a layer comprising a block copolymer formed on a substrate to suffer phase separation, wherein the composition comprises a copolymer having: (A) a unit structure resulting from polymerizing a styrene compound containing a tert-butyl group, (B) a unit structure resulting from polymerizing an aromatic group-containing vinyl compound containing no hydroxy group, which differs from unit structure (A), (C) a unit structure resulting from polymerizing a compound containing (a)an (meth)acryloyl group and containing no hydroxy group, and (D) a unit structure resulting from polymerizing a crosslink-forming group-containing compound, wherein the crosslink-forming group is a hydroxy group, an epoxy group, a protected hydroxy group, or a protected carboxyl group, wherein the copolymer has a copolymerization ratio of: (A) 25 to 90% by mole, (B) more than 0 to 65% by mole, (C) 0 to 65% by mole, and (D) 10 to 20% by mole, wherein the copolymer in the composition has a proportion of an amount of unit structures containing an aromatic group based on a total amount of unit structures (A), (B), and (C) of 81 to 90% by mole, and wherein the unit structure (B) is represented by formula (4-1) or (4-2): wherein in formula (4-1), each of n quantity of Y independently represents an alkyl group, an alkoxy group, a cyano group, an amide group, an alkoxycarbonyl group, or a thioalkyl group, and n represents an integer of 1 to 5; wherein in formula (4-2), each of n quantity of Y independently represents a halogen atom, an alkyl group, an alkoxy group, a cyano group, an amide group, an alkoxycarbonyl group, or a thioalkyl group, and n represents an integer of 0 to 7. ### Claim 2 (depends on 1) The composition according to claim 1, wherein the block copolymer formed on the substrate is a block copolymer in which a silicon-containing polymer containing a structural unit from styrene substituted with a silicon-containing group, and either a silicon-non-containing polymer containing a structural unit from styrene optionally substituted with an organic group or a silicon-non-containing polymer containing a structural unit from a structure resulting from polymerizing a lactide are bound. ### Claim 3 (depends on 1) The composition according to claim 1, wherein the unit structure (A) is represented by formula (1): wherein one or two of R1 to R3 are a tert-butyl group. ### Claim 4 (depends on 1) The composition according to claim 1, wherein the unit structure (D) is represented by formula (2-1), (2-2), (3-1), or (3-2): wherein, in formulae (2-1) and (2-2), each of n quantity of X independently represents a hydroxy group, a halogen atom, an alkyl group, an alkoxy group, a cyano group, an amide group, an alkoxycarbonyl group, or a thioalkyl group, and n represents an integer of 1 to 7, wherein, in formulae (3-1) and (3-2), R4 represents a hydrogen atom or a methyl group, and R5 represents a hydroxyphenyl group or a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms, which contains a hydroxy group and is optionally substituted with a halogen atom. ### Claim 5 (depends on 1) The composition according to claim 1, wherein the unit structure (C) is represented by formula (5-1) or (5-2): wherein, in formulae (5-1) and (5-2), R9 represents a hydrogen atom or a methyl group, and R10 independently represents a hydrogen atom, an alkoxy group having 1 to 5 carbon atoms, a benzyl group, an anthrylmethyl group, or a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms, which is optionally substituted with a halogen atom. ### Claim 6 (depends on 1) The composition according to claim 1, wherein the unit structure (B) is a unit structure including vinylnaphthalene. ### Claim 7 (depends on 1) A method for producing a phase-separated pattern of a block copolymer, comprising the steps of: (1) forming an underlayer film on a substrate using the composition according to claim 1; (2) forming a block copolymer layer on the underlayer film; and (3) causing the block copolymer layer formed on the underlayer film to suffer phase separation. ### Claim 8 (depends on 7) The method according to claim 7, further comprising the step of forming an upper layer film on the block copolymer layer between step (2) and step (3). ### Claim 9 (depends on 7) The method according to claim 7 wherein a block copolymer in the block copolymer layer is a block copolymer in which a silicon-containing polymer containing a structural unit from styrene substituted with a silicon-containing group, and either a silicon-non-containing polymer containing a structural unit from styrene optionally substituted with an organic group or a silicon-non-containing polymer containing a structural unit from a structure resulting from polymerizing a lactide are bound. ### Claim 10 (depends on 1) A method for producing a semiconductor device, comprising the steps of: (1) forming an underlayer film on a substrate using the composition according to claim 1; (2) forming a block copolymer layer on the underlayer film; (3) causing the block copolymer layer formed on the underlayer film to suffer phase separation; (4) subjecting the phase-separated block copolymer layer to etching; and (5) subjecting the substrate to etching. ### Claim 11 (depends on 10) The method according to claim 10, wherein a block copolymer in the block copolymer layer is a block copolymer in which a silicon-containing polymer containing a structural unit from styrene substituted with a silicon-containing group, and either a silicon-non-containing polymer containing a structural unit from styrene optionally substituted with an organic group or a silicon-non-containing polymer containing a structural unit from a structure resulting from polymerizing a lactide are bound. ### Claim 12 An underlayer film for use in causing a layer comprising a block copolymer formed on a substrate to suffer phase separation, wherein the underlayer film comprises a copolymer having: (A) a unit structure resulting from polymerizing a styrene compound containing a tert-butyl group, (B) a unit structure resulting from polymerizing an aromatic group-containing vinyl compound containing no hydroxy group, which differs from unit structure (A), (C) a unit structure resulting from polymerizing a compound containing (a)an (meth)acryloyl group and containing no hydroxy group, and (D) a unit structure resulting from polymerizing a crosslink-forming group-containing compound, wherein the crosslink-forming group is a hydroxy group, an epoxy group, a protected hydroxy group, or a protected carboxyl group, wherein the copolymer has a copolymerization ratio of: (A) 25 to 90% by mole, (B) more than 0 to 65% by mole, (C) 0 to 65% by mole, and (D) 10 to 20% by mole, wherein the copolymer has a proportion of an amount of unit structures containing an aromatic group based on a total amount of unit structures (A), (B), and (C) of 81 to 90% by mole, and wherein the unit structure (B) is represented by formula (4-1) or (4-2): wherein in formula (4-1), each of n quantity of Y independently represents an alkyl group, an alkoxy group, a cyano group, an amide group, an alkoxycarbonyl group, or a thioalkyl group, and n represents an integer of 1 to 5; wherein in formula (4-2), each of n quantity of Y independently represents a halogen atom, an alkyl group, an alkoxy group, a cyano group, an amide group, an alkoxycarbonyl group, or a thioalkyl group, and n represents an integer of 0 to 7. ### Claim 13 (depends on 12) The underlayer film according to claim 12, wherein the block copolymer formed on the substrate is a block copolymer in which a silicon-containing polymer containing a structural unit from styrene substituted with a silicon-containing group, and either a silicon-non-containing polymer containing a structural unit from styrene optionally substituted with an organic group or a silicon-non-containing polymer containing a structural unit from a structure resulting from polymerizing a lactide are bound. ### Claim 14 (depends on 1) The composition according to claim 1, wherein the composition further contains a crosslinkable compound. ### Claim 15 (depends on 14) The composition according to claim 14, wherein the composition contains the crosslinkable compound in a proportion to the copolymer contained in the composition of from 5 to 50% by mass. ### Claim 16 (depends on 1) The composition according to claim 1, wherein the composition further contains a nitrogen-containing compound having 2 to 4 nitrogen atoms, and substituted with a methylol group.