Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
  • C07C39/12—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings
  • C07C39/15—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings with all hydroxy groups on non-condensed rings, e.g. phenylphenol
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
  • C07C69/02—Esters of acyclic saturated monocarboxylic acids having the carboxyl group bound to an acyclic carbon atom or to hydrogen
  • C07C69/12—Acetic acid esters
  • C07C69/21—Acetic acid esters of hydroxy compounds with more than three hydroxy groups
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/004—Photosensitive materials
  • G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
  • G03F7/11—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers having cover layers or intermediate layers, e.g. subbing layers
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/26—Processing photosensitive materials; Apparatus therefor

Definitions

• the present invention relates to a polyphenol compound, a composition for forming a lithography film containing the polyphenol compound, an underlayer film for lithography formed using the composition, and a pattern forming method (for example, a resist pattern forming method) using the composition. or circuit pattern forming method).
• a pattern forming method for example, a resist pattern forming method
• the wavelength of the lithography light source used during resist pattern formation has been shortened from KrF excimer laser (248 nm) to ArF excimer laser (193 nm).
• KrF excimer laser 248 nm
• ArF excimer laser (193 nm).
• resist patterns become finer, problems arise such as resolution problems or resist patterns collapsing after development, and therefore it is desired to make resists thinner.
• simply thinning the resist makes it difficult to obtain a resist pattern with a thickness sufficient for substrate processing. For this reason, it has become necessary to create not only a resist pattern but also a resist underlayer film between the resist and the semiconductor substrate to be processed, and a process in which this resist underlayer film also functions as a mask during substrate processing. .
• a lower layer film-forming material for a multilayer resist process contains a resin component having at least a substituent that separates to form a sulfonic acid residue and a solvent (see Patent Document 1 below).
• a resist underlayer film material containing a polymer having a specific repeating unit has been proposed as a material for realizing a resist underlayer film for lithography having a dry etching rate selectivity smaller than that of a resist (see Patent Document 2 below). reference.).
• a resist underlayer film material containing a polymer having a specific repeating unit has been proposed as a material for realizing a resist underlayer film for lithography having a dry etching rate selectivity smaller than that of a resist.
• a method for forming a silicon nitride film for example, a method for forming a silicon nitride film (see Patent Document 6 below), a CVD method for forming a silicon nitride film (see Patent Document 6), etc. 7) is known. Further, as an intermediate layer material for a three-layer process, a material containing a silsesquioxane-based silicon compound is known (see Patent Documents 8 and 9 below).
• the present invention provides a composition for forming a lithography film useful for forming a photoresist underlayer film having excellent embedding properties into a stepped substrate and film flatness, and a composition comprising the above composition.
• An object of the present invention is to provide an underlayer film for lithography formed using the above composition, a pattern forming method using the above composition, and a novel polyphenol compound useful for the above composition.
• the present inventors have discovered that the above problems can be solved by a composition for forming a film for lithography using a compound having a specific structure, and have completed the present invention. reached. That is, the present invention is as follows.
• a composition for forming a film for lithography comprising a polyphenol compound represented by the following formula (1).
• A is a single bond or an n-valent group;
• Ar 1 and Ar 2 may each independently be the same group or different groups, and are a benzene structure, a naphthalene structure, an anthracene structure, a phenanthrene structure, a pyrene structure, a fluorene structure, a biphenyl structure, a diphenylmethane structure or a terphenyl structure;
• X is an alkylene group, an oxygen atom, a sulfur atom;
• R 1 and R 2 may each independently be the same group or different groups, and may be an alkyl group having 1 to 30 carbon atoms which may have a substituent, or an alkyl group having 6 to 30 carbon atoms which may have a substituent.
• aryl groups optionally substituted alkenyl groups with 2 to 30 carbon atoms, optionally substituted alkynyl groups with 2 to 30 carbon atoms, optionally with substituents
• P 1 and P 2 may each independently be the same group or different groups, and may be a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, or a substituent.
• composition for forming a film for lithography wherein the polyphenol compound represented by the formula (1) is a polyphenol compound represented by the following formula (2).
• A, P 1 , P 2 , R 1 , R 2 and n are synonymous with formula (1), j is an integer of 1 to 3, k is an integer of 1 to 5, m is an integer of 1 to 4, l1 is an integer of 0 to 2, and l2 is an integer of 0 to 4.
• n and m do not become 1 at the same time.
• the above P 1 and the above P 2 are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, or a carbon number 2 to 20 which may have a substituent.
• an alkoxyalkyl group having 2 to 20 carbon atoms which may have a substituent an alkylsulfonyl group having 1 to 10 carbon atoms which may have a substituent, and an alkylcarbonyl group having 1 to 10 carbon atoms which may have a substituent;
• composition for forming a film for lithography according to any one of the above.
• composition for forming a film for lithography according to ⁇ 5> above further comprising at least one selected from the group consisting of a solvent, a crosslinking agent, an acid generator, and an acid diffusion control agent.
• composition for forming a lithography film according to ⁇ 6> above which is used as a composition for a lithography underlayer film.
• ⁇ 9> forming a lower layer film on the substrate using the lithography film forming composition according to any one of ⁇ 1> to ⁇ 7>; a step of forming at least one photoresist layer on the lower layer film; and a step of irradiating a predetermined region of the photoresist layer with radiation and developing it.
• a pattern forming method including: ⁇ 10> forming a lower layer film on the substrate using the lithography film forming composition according to any one of ⁇ 1> to ⁇ 7>; forming an intermediate layer film on the lower layer film using a resist intermediate layer film material containing silicon atoms; forming at least one photoresist layer on the intermediate layer film; irradiating a predetermined region of the photoresist layer with radiation and developing it to form a resist pattern; etching the intermediate layer film using the resist pattern as a mask to obtain an intermediate layer film pattern; a step of etching the lower layer film using the intermediate layer film pattern as an etching mask to obtain a lower layer film pattern; a step of etching the substrate using the lower layer film pattern as an etching mask to form a pattern on the substrate;
• a pattern forming method including: ⁇ 11> A polyphenol compound including a polyphenol compound represented by the following formula (1).
• A is a single bond or an n-valent group
• Ar 1 and Ar 2 may each independently be the same group or different groups, and are a benzene structure, a naphthalene structure, an anthracene structure, a phenanthrene structure, a pyrene structure, a fluorene structure, a biphenyl structure, a diphenylmethane structure or a terphenyl structure
• X is an alkylene group, an oxygen atom, a sulfur atom
• R 1 and R 2 may each independently be the same group or different groups, and may be an alkyl group having 1 to 30 carbon atoms which may have a substituent, or an alkyl group having 6 to 30 carbon atoms which may have a substituent.
• aryl groups optionally substituted alkenyl groups with 2 to 30 carbon atoms, optionally substituted alkynyl groups with 2 to 30 carbon atoms, optionally with substituents
• P 1 and P 2 may each independently be the same group or different groups, and may be a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, or a substituent.
• an alkoxyalkyl group having 2 to 20 carbon atoms which may have a substituent an alkylsulfonyl group having 1 to 10 carbon atoms which may have a substituent, and an alkylcarbonyl group having 1 to 10 carbon atoms which may have a substituent; Any of the above ⁇ 11> to ⁇ 13>, which is a group selected from the group consisting of an arylsulfonyl group having 6 to 20 carbon atoms, or an acyl group having 2 to 13 carbon atoms, which may have a substituent.
• a composition for forming a film for lithography useful for forming a photoresist underlayer film having excellent embeddability into a stepped substrate and film flatness and a composition for forming a film for lithography using the composition. It is possible to provide an underlayer film for lithography to be formed, a pattern forming method using the composition, and a novel polyphenol compound useful for the composition.
• this embodiment a mode for carrying out the present invention (hereinafter also referred to as "this embodiment") will be described in detail.
• the present embodiment below is an illustration for explaining the present invention, and is not intended to limit the present invention to the following content.
• the present invention can be implemented with appropriate modifications within the scope of its gist.
• the polyphenol compound of the present embodiment and the film-forming composition for lithography of the present embodiment will be explained in this order.
• the polyphenol compound of this embodiment is represented by the following formula (1).
• the polyphenol compound of this embodiment can be suitably used in a film-forming composition for lithography, and a composition using the compound has high film-forming properties and solvent solubility, and is suitable for wet processes. It is possible to form a lower layer film which is excellent in embedding into the stepped substrate and flatness of the film, and also has excellent curability, heat resistance of the film, and etching resistance of the film.
• A is a single bond or an n-valent group
• Ar 1 and Ar 2 may each independently be the same group or different groups, and are a benzene structure, a naphthalene structure, an anthracene structure, a phenanthrene structure, a pyrene structure, a fluorene structure, a biphenyl structure, a diphenylmethane structure or a terphenyl structure
• X is an alkylene group, an oxygen atom, a sulfur atom
• R 1 and R 2 may each independently be the same group or different groups, and may be an alkyl group having 1 to 30 carbon atoms which may have a substituent, or an alkyl group having 6 to 30 carbon atoms which may have a substituent.
• aryl groups optionally substituted alkenyl groups with 2 to 30 carbon atoms, optionally substituted alkynyl groups with 2 to 30 carbon atoms, optionally with substituents
• An amino group, halogen atom, cyano group, nitro group, thiol group, or heterocyclic group having 0 to 30 carbon atoms, which may have P 1 and P 2 may each independently be the same group or different groups, and may be a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, or a substituent.
• substitution means that one or more hydrogen atoms in a functional group are replaced with a substituent, unless otherwise defined.
• the "substituent” is not particularly limited, but includes, for example, a halogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, a thiol group, a heterocyclic group, an alkyl group having 1 to 30 carbon atoms, and an alkyl group having 6 to 20 carbon atoms.
• Examples include aryl group, alkoxy group having 1 to 30 carbon atoms, alkenyl group having 2 to 30 carbon atoms, alkynyl group having 2 to 30 carbon atoms, acyl group having 1 to 30 carbon atoms, and amino group having 0 to 30 carbon atoms. It will be done.
• the alkyl group may be a linear aliphatic hydrocarbon group, a branched aliphatic hydrocarbon group, or a cyclic aliphatic hydrocarbon group.
• A represents a single bond or an n-valent group.
• the n-valent group is preferably an n-valent group having 0 to 60 carbon atoms that may contain a hydrogen atom or a hetero atom (for example, oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, iodine), and more preferably is an n-valent group having 0 to 10 carbon atoms.
• the n-valent group is preferably a hydrocarbon group, such as an n-valent alkyl group, an aryl group, an aryl group having an alkyl group, etc.
• A is preferably an n-valent group selected from a single bond, a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a combination thereof.
• a group other than a group in which three or more repeating units of the same structure are connected can be used.
• the compound represented by formula (1) can be a compound other than compound A below.
• Preferred examples of A include a single bond or the following groups. Note that * in the following compounds indicates a binding site.
• Ar 1 and Ar 2 may each independently be the same group or different groups, and are a benzene structure, a naphthalene structure, an anthracene structure, a phenanthrene structure, a pyrene structure, a fluorene structure, a biphenyl structure, a diphenylmethane structure, or a terphenyl structure; From the viewpoint of availability, a benzene structure, a naphthalene structure, and a biphenyl structure are more preferable.
• X is an alkylene group, an oxygen atom, or a sulfur atom, preferably an alkylene group, and more preferably a methylene group.
• R 1 and R 2 may each independently be the same group or different groups, and may be an alkyl group having 1 to 30 carbon atoms which may have a substituent, or an alkyl group having 6 to 30 carbon atoms which may have a substituent.
• 30 aryl groups optionally substituted alkenyl groups with 2 to 30 carbon atoms, optionally substituted alkynyl groups with 2 to 30 carbon atoms, optionally with substituents
• R 1 and R 2 are preferably an alkyl group having 1 to 30 carbon atoms (preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms) which may have a substituent, and an alkyl group having a substituent.
• an aryl group having 6 to 30 carbon atoms which may be substituted an alkoxy group having 1 to 30 carbon atoms which may have a substituent, more preferably 1 to 30 carbon atoms which may have a substituent an alkyl group, an aryl group having 6 to 30 carbon atoms which may have a substituent, specifically a hydroxyl group, and at least one of an aryl group (e.g. phenyl group) and an alkyl group (e.g. methyl group).
• Examples include a phenyl group having 1 and .
• P 1 and P 2 may each independently be the same group or different groups, and may be a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, or a substituent.
• P 1 and P 2 are specifically methyl group, ethyl group, normal propyl group, isopropyl group, normal butyl group, isobutyl group, tertiary butyl group, pentyl group, hexyl group, heptyl group, octyl group, benzyl group , methoxybenzyl group, dimethoxybenzyl group, methylbenzyl group, methoxymethyl group, ethoxyethyl group, ethoxypropyl group, tetrahydropyranyl group, methylthiomethyl group, benzyloxymethyl group, methoxyethoxymethyl group, trityl group, monomethoxytrityl group group, dimethoxytrityl group, trimethylsilyl group, triethylsilyl group, triisopropylsilyl group, tert-butyldimethylsilyl group, tert-butyldipheny
• the polyphenol compound represented by the formula (1) is preferably a compound represented by the following formula (2) from the viewpoint of solubility, curability, heat resistance, and raw material availability, and more preferably a compound represented by the following formula (3). It is a compound represented by (In formula (2), A, P 1 , P 2 , R 1 , R 2 and n are synonymous with formula (1), j is an integer of 1 to 3, k is an integer of 1 to 5, m is an integer of 1 to 4, l1 is an integer of 0 to 2, and l2 is an integer of 0 to 4. However, n and m do not become 1 at the same time. ) (In formula (3), A, R 1 , R 2 , P 1 , P 2 , l1 and l2, and n have the same meanings as in formula (2).)
• reaction A a compound represented by the following structural formula (4) and a compound represented by the following structural formula (5) (a2)
• reaction A a compound represented by the following structural formula (5)
• reaction B a phenol protection reaction
• the compound (a2) represented by the structural formula (5) is, for example, phenol, cresol, resorcinol, 2,4-dimethylphenol, 2-phenylphenol, 3-phenylphenol, 4-phenylphenol, 2,6 -dimethylphenol, 2,6-diphenylphenol, 4-t-butylphenol, 2-t-butylphenol, 2-amylphenol, 4-amylphenol, 4-t-octylphenol, 4,4'-biphenol, 2,2' Examples include various phenols such as -biphenol, 2,2'-dimethyl-4,4'-biphenol, and naphthol. Among these, phenol, cresol, 2-phenylphenol, 2,6-dimethylphenol, and 4-t-octylphenol are preferred from the viewpoint of availability and handling.
• the reaction ratio between the compound (a1) and the compound (a2) is 1/1 to 1/100 from the viewpoint of increasing the purity of the target product.
• the reaction A can be carried out in the presence of an acid catalyst or a basic catalyst.
• the acid catalyst can be appropriately selected from known ones and is not particularly limited. Inorganic acids and organic acids are widely known as such acid catalysts. Specific examples of the acid catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, hydrobromic acid, and hydrofluoric acid; oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, citric acid, fumaric acid, and maleic acid.
• Organic acids such as acid, formic acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, naphthalenesulfonic acid, naphthalene disulfonic acid; zinc chloride, aluminum chloride , Lewis acids such as iron chloride and boron trifluoride; solid acids such as silicotungstic acid, phosphotungstic acid, silicomolybdic acid, and phosphomolybdic acid; ion exchange resins for catalysts; strongly acidic ion exchange resins, etc. However, it is not particularly limited to these. Among these, methanesulfonic acid, p-toluenesulfonic acid, sulfuric acid, hydrochloric acid, and strongly acidic ion exchange resins are preferred.
• protective reagents that can be used when carrying out the phenol protection reaction are not particularly limited, but include, for example, methyl iodide, dimethyl carbonate, ethyl iodide, diethyl carbonate, bromo tertiary butoxide, isobutene, benzyl Examples include bromide, ditertiarybutyl dicarbonate, acetic anhydride, mesyl chloride, vinyl ethyl ether, dihydropyran, chloromethyl methyl ether, and the like.
• polyphenol compound of this embodiment the following compounds can be cited as preferred examples from the viewpoints of solubility, heat resistance, and availability of raw materials.
• the composition for forming a film for lithography of this embodiment contains the polyphenol compound of this embodiment described above.
• the film-forming composition for lithography of this embodiment has high film-forming properties and solvent solubility, and can be applied to a wet process, and has excellent embedding properties in the lower layer film step substrate and film flatness. Furthermore, it is possible to form a lower layer film having excellent curability, film heat resistance, and film etching resistance.
• the composition for forming a film for lithography of this embodiment contains the polyphenol compound of this embodiment as an essential component, and may further contain various optional components in consideration of being used as a material for forming a lower layer film for lithography. can do. Specifically, it is preferable that the film-forming composition for lithography of this embodiment further contains at least one selected from the group consisting of a solvent, an acid generator, and a crosslinking agent.
• the content of the polyphenol compound of the present embodiment is not particularly limited, but is 1 to 33 parts by mass based on 100 parts by mass of the total amount including the solvent.
• the amount is preferably from 2 to 25 parts by weight, and even more preferably from 3 to 20 parts by weight.
• the lithography film forming composition of this embodiment can be applied to wet processes and has excellent heat resistance and etching resistance. Furthermore, since the composition for forming a film for lithography of the present embodiment contains the polyphenol compound of the present embodiment, deterioration of the film during high temperature baking is suppressed, and a lower layer film having excellent etching resistance against oxygen plasma etching etc. is formed. can do. Furthermore, since the lithography film forming composition of the present embodiment has excellent adhesion to the resist layer, an excellent resist pattern can be obtained.
• the composition for forming a film for lithography of this embodiment may contain already known materials for forming a lower layer film for lithography, etc., as long as the desired effects of this embodiment are not impaired.
• solvent As the solvent used in the composition for forming a film for lithography of this embodiment, any known solvent can be used as appropriate, as long as it dissolves at least the polyphenol compound of this embodiment.
• the solvent include, but are not particularly limited to, those described in International Publication No. 2013/024779. These solvents can be used alone or in combination of two or more.
• cyclohexanone propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), a mixed solvent of PGMEA and PGME, ethyl lactate, methyl hydroxyisobutyrate, and anisole are particularly preferred from the viewpoint of safety. .
• the content of the solvent is not particularly limited, but from the viewpoint of solubility and film formation, it is preferably 100 to 10,000 parts by mass, and 200 to 5 parts by mass, based on 100 parts by mass of the polyphenol compound of the present embodiment. ,000 parts by weight is more preferable, and even more preferably 200 to 1,000 parts by weight.
• the composition for forming a film for lithography of the present embodiment may contain a crosslinking agent as necessary from the viewpoint of suppressing intermixing.
• the crosslinking agent that can be used in this embodiment is not particularly limited, and includes, for example, a phenol compound, an epoxy compound, a cyanate compound, an amino compound, a benzoxazine compound, an acrylate compound, a melamine compound, a guanamine compound, a glycoluril compound, and a urea compound. , isocyanate compounds, azide compounds, and the like. Specific examples of these crosslinking agents include those described in International Publication No. 2018/016614 and International Publication No. 2013/024779.
• crosslinking agents can be used alone or in combination of two or more.
• phenol compounds containing condensed aromatic rings are more preferred from the viewpoint of improving etching resistance.
• methylol group-containing phenol compounds are more preferred.
• the content of the crosslinking agent is not particularly limited, but is preferably 5 to 50 parts by mass, more preferably 5 to 50 parts by mass, based on 100 parts by mass of the polyphenol compound of the present embodiment. Preferably it is 10 to 40 parts by mass.
• Crosslinking accelerator A crosslinking accelerator for accelerating crosslinking and curing reactions can be used in the lithography film forming composition of the present embodiment, if necessary.
• the crosslinking accelerator is not particularly limited as long as it promotes crosslinking and curing reactions, and examples thereof include amines, imidazoles, organic phosphines, Lewis acids, and the like. These crosslinking accelerators can be used alone or in combination of two or more. Among these, imidazoles or organic phosphines are preferred, and imidazoles are more preferred from the viewpoint of lowering the crosslinking temperature.
• crosslinking accelerator known ones can be used, and examples thereof include, but are not limited to, those described in International Publication No. 2018/016614. From the viewpoint of heat resistance and curing acceleration, 2-methylimidazole, 2-phenylimidazole, and 2-ethyl-4-methylimidazole are particularly preferred.
• the content of the crosslinking accelerator is usually preferably 0.1 to 10 parts by weight based on 100 parts by weight of the total weight of the composition, and more preferably 0.1 to 10 parts by weight, and more preferably 100 parts by weight of the total weight of the composition. From the viewpoint of ease and economy, the amount is 0.1 to 5 parts by weight, more preferably 0.1 to 3 parts by weight.
• a radical polymerization initiator can be added to the composition for forming a film for lithography according to the present embodiment, if necessary.
• the radical polymerization initiator may be a photopolymerization initiator that starts radical polymerization with light, or a thermal polymerization initiator that starts radical polymerization with heat.
• the radical polymerization initiator may be, for example, at least one selected from the group consisting of ketone photopolymerization initiators, organic peroxide polymerization initiators, and azo polymerization initiators.
• Such a radical polymerization initiator is not particularly limited, and conventionally used ones can be appropriately employed. Examples include those described in International Publication No. 2018/016614. Among these, particularly preferred are dicumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, and t-butylcumyl peroxide from the viewpoint of raw material availability and storage stability. .
• radical polymerization initiator used in this embodiment one type of these may be used alone or two or more types may be used in combination, and other known polymerization initiators may be further used in combination. .
• the composition for forming a film for lithography of the present embodiment may contain an acid generator as necessary from the viewpoint of further promoting the crosslinking reaction due to heat.
• acid generators there are known ones that generate acid through thermal decomposition and those that generate acid when exposed to light, and any of these can be used.
• the acid generator is not particularly limited, but for example, those described in International Publication No. 2013/024779 can be used.
• an acid generator can be used individually or in combination of 2 or more types.
• the content of the acid generator is not particularly limited, but may be 0.1 to 50 parts by mass based on 100 parts by mass of the polyphenol compound of the present embodiment. It is preferably 0.5 to 40 parts by mass, and more preferably 0.5 to 40 parts by mass.
• composition for forming a film for lithography of the present embodiment may contain a basic compound from the viewpoint of improving storage stability.
• the basic compound serves as a quencher for the acid to prevent the acid generated in a trace amount from the acid generator from proceeding with the crosslinking reaction.
• Examples of such basic compounds include primary, secondary, or tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxy group, Examples include nitrogen-containing compounds having a sulfonyl group, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amide derivatives, imide derivatives, etc., but are not particularly limited thereto.
• the basic compound used in this embodiment is not particularly limited, but for example, those described in International Publication No. 2013/024779 can be used.
• a basic compound can be used individually or in combination of 2 or more types.
• the content of the basic compound is not particularly limited, but is preferably 0.001 to 2 parts by mass based on 100 parts by mass of the polyphenol compound of the present embodiment. It is preferably 0.01 to 1 part by mass, more preferably 0.01 to 1 part by mass. By setting it within the above-mentioned preferred range, storage stability tends to be improved without excessively impairing the crosslinking reaction.
• the composition for forming a film for lithography of the present embodiment may contain other resins and/or compounds for the purpose of imparting thermosetting properties and controlling absorbance.
• other resins and/or compounds include naphthol resin, xylene resin naphthol-modified resin, phenol-modified naphthalene resin, polyhydroxystyrene, dicyclopentadiene resin, (meth)acrylate, dimethacrylate, and trimethacrylate.
• the composition for forming a film for lithography of this embodiment may contain known additives.
• the known additives include, but are not limited to, ultraviolet absorbers, surfactants, colorants, nonionic surfactants, and the like.
• the composition for forming a film for lithography can be suitably used as a composition for forming an underlayer film for lithography.
• the method for forming a lower layer film for lithography of this embodiment includes a step of forming a lower layer film on a substrate using the composition for forming a film for lithography of this embodiment.
• a resist pattern forming method using the lithography film forming composition of the present embodiment includes a step (A-1) of forming a lower layer film on a substrate using the lithography film forming composition of the present embodiment. , a step (A-2) of forming at least one photoresist layer on the lower layer film, and a step (A-2) of irradiating a predetermined region of the photoresist layer with radiation and developing it to form a resist pattern (A-2). -3).
• a circuit pattern forming method using the lithography film forming composition of the present embodiment includes a step (B-1) of forming a lower layer film on a substrate using the lithography film forming composition of the present embodiment. , forming an intermediate layer film on the lower layer film using a resist intermediate layer film material containing silicon atoms (B-2), and forming at least one photoresist layer on the intermediate layer film.
• step (B-4) a step (B-5) of etching the intermediate layer film using the resist pattern as a mask to form an intermediate layer film pattern, and using the obtained intermediate layer film pattern as an etching mask.
• the formation method of the lithography underlayer film of this embodiment is not particularly limited as long as it is formed from the lithography film forming composition of this embodiment, and any known method can be applied.
• any known method can be applied.
• the lithography film forming composition of the present embodiment onto a substrate by a known coating method or printing method such as spin coating or screen printing, and then removing it by volatilizing the organic solvent, A lower layer film can be formed.
• the baking temperature is not particularly limited, but is preferably in the range of 80 to 450°C, more preferably 200 to 400°C.
• the baking time is also not particularly limited, but is preferably within a range of 10 to 300 seconds.
• the thickness of the lower layer film can be appropriately selected depending on the required performance, and is not particularly limited, but it is usually preferably about 30 to 20,000 nm, more preferably 50 to 15,000 nm. It is preferable.
• a silicon-containing resist layer or a single-layer resist made of ordinary hydrocarbon is applied on top of it, and in the case of a three-layer process, a silicon-containing intermediate layer is placed on top of it, and then a silicon-containing intermediate layer is placed on top of it in the case of a three-layer process.
• a single resist layer containing no silicon is produced.
• known photoresist materials can be used to form this resist layer.
• a silicon-containing resist layer or a single layer resist made of ordinary hydrocarbon can be formed on the lower layer film.
• a silicon-containing intermediate layer can be formed on the lower layer film, and a silicon-free single-layer resist layer can be further formed on the silicon-containing intermediate layer.
• the photoresist material for forming the resist layer can be appropriately selected from known materials and is not particularly limited.
• a silicon-containing resist material for a two-layer process from the viewpoint of oxygen gas etching resistance, a silicon atom-containing polymer such as a polysilsesquioxane derivative or a vinylsilane derivative is used as a base polymer, and an organic solvent, an acid generator, A positive photoresist material containing a basic compound or the like if necessary is preferably used.
• the silicon atom-containing polymer known polymers used in this type of resist material can be used.
• a polysilsesquioxane-based interlayer is preferably used as the silicon-containing interlayer for the three-layer process. Reflection tends to be effectively suppressed by providing the intermediate layer with an effect as an antireflection film. For example, in a 193 nm exposure process, if a material containing many aromatic groups and high substrate etching resistance is used as the lower layer film, the k value will increase and the substrate reflection will tend to increase, but it is necessary to suppress the reflection with an intermediate layer. Accordingly, substrate reflection can be reduced to 0.5% or less.
• Intermediate layers having such an antireflection effect include, but are not limited to, polysilsesquioxides cross-linked with acid or heat that have a phenyl group or a light-absorbing group having a silicon-silicon bond for 193 nm exposure. Sun is preferably used.
• an intermediate layer formed by a chemical vapor deposition (CVD) method can also be used.
• a chemical vapor deposition (CVD) method for example, a SiON film is known, although it is not limited to the following.
• a wet process such as a spin coating method or screen printing than by a CVD method.
• the upper layer resist in the three-layer process may be either positive type or negative type, and the same resist as the commonly used single layer resist can be used.
• the lower layer film in this embodiment can also be used as an antireflection film for a normal single-layer resist or a base material for suppressing pattern collapse. Since the lower layer film of this embodiment has excellent etching resistance for base processing, it can also be expected to function as a hard mask for base processing.
• a wet process such as spin coating or screen printing is preferably used, as in the case of forming the lower layer film.
• prebaking is usually performed, and this prebaking is preferably performed at 80 to 180° C. for 10 to 300 seconds.
• a resist pattern can be obtained by performing exposure, post-exposure bake (PEB), and development according to a conventional method.
• the thickness of the resist film is not particularly limited, but is generally preferably 30 to 500 nm, more preferably 50 to 400 nm.
• the exposure light may be appropriately selected and used depending on the photoresist material used.
• high-energy rays with a wavelength of 300 nm or less specifically excimer lasers with a wavelength of 248 nm, 193 nm, or 157 nm, soft X-rays with a wavelength of 3 to 20 nm, electron beams, X-rays, etc. can be used.
• gas etching is preferably used for etching the lower layer film in the two-layer process.
• gas etching etching using oxygen gas is suitable.
• oxygen gas it is also possible to add an inert gas such as He or Ar, or a gas such as CO, CO 2 , NH 3 , SO 2 , N 2 , NO 2 or H 2 .
• gas etching can also be performed using only CO, CO 2 , NH 3 , N 2 , NO 2 , or H 2 gas without using oxygen gas.
• the latter gas is preferably used for sidewall protection to prevent undercutting of pattern sidewalls.
• gas etching is also preferably used for etching the intermediate layer in the three-layer process.
• the gas etching the same gas etching as described in the two-layer process can be applied.
• the lower layer film can be processed by performing, for example, oxygen gas etching using the intermediate layer pattern as a mask as described above.
• a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiON film) is formed by a CVD method, an atomic layer deposition (ALD) method, etc. Ru.
• ALD atomic layer deposition
• Ru atomic layer deposition
• the method for forming the nitride film is not limited to the following, for example, the methods described in Japanese Patent Application Publication No. 2002-334869 and International Publication No. 2004/066377 can be used.
• it is possible to form a photoresist film directly on such an intermediate layer film it is also possible to form an organic anti-reflection coating (BARC) on the intermediate layer film by spin coating, and then form a photoresist film on it. You may.
• BARC organic anti-reflection coating
• a polysilsesquioxane-based intermediate layer is also preferably used.
• the intermediate layer There is a tendency that reflection can be effectively suppressed by providing the resist intermediate layer film with an effect as an antireflection film.
• Specific materials for the polysilsesquioxane-based intermediate layer include, but are not limited to, those described in JP-A No. 2007-226170 and JP-A No. 2007-226204, for example. Can be used.
• the next etching of the substrate can also be carried out by a conventional method.
• the substrate is SiO 2 or SiN
• etching using chlorine or bromine gas Etching can be performed mainly using gas.
• the silicon-containing resist in the two-layer resist process and the silicon-containing intermediate layer in the three-layer process are peeled off at the same time as the substrate is processed.
• the substrate is etched with chlorine-based or bromine-based gas, the silicon-containing resist layer or silicon-containing intermediate layer is removed separately, and generally dry etching removal using fluorocarbon gas is performed after substrate processing. .
• the lower layer film in this embodiment is characterized by excellent etching resistance of these substrates.
• the substrate can be appropriately selected and used from known substrates, and examples thereof include, but are not limited to, Si, ⁇ -Si, p-Si, SiO 2 , SiN, SiON, W, TiN, Al, etc. .
• the substrate may be a laminate having a film to be processed (substrate to be processed) on a base material (support).
• Such films to be processed include various low-k films such as Si, SiO 2 , SiON, SiN, p-Si, ⁇ -Si, W, W-Si, Al, Cu, and Al-Si, and their stopper films.
• the thickness of the substrate to be processed or the film to be processed is not particularly limited, but it is usually preferably about 50 to 1,000,000 nm, more preferably 75 to 500,000 nm.
• a resist permanent film can also be produced using the film-forming composition of this embodiment.
• a permanent resist film formed by applying the film-forming composition of the present embodiment to a substrate or the like is suitable as a permanent film that remains in the final product after forming a resist pattern as necessary.
• Specific examples of permanent films include, but are not limited to, in the semiconductor device field, such as solder resists, packaging materials, underfill materials, package adhesive layers for circuit elements, adhesive layers between integrated circuit elements and circuit boards, and thin displays.
• Related products include thin film transistor protective films, liquid crystal color filter protective films, black matrices, spacers, etc.
• the permanent film made of the film-forming composition of this embodiment has excellent heat resistance and moisture resistance, and also has the very excellent advantage of being less likely to be contaminated by sublimation components.
• the material has high sensitivity, high heat resistance, and moisture absorption reliability with little deterioration of image quality due to important contamination.
• the film-forming composition of this embodiment is used for resist permanent film applications, in addition to the curing agent, other resins, surfactants, dyes, fillers, crosslinking agents, dissolution promoters, etc. may be added as necessary.
• other resins, surfactants, dyes, fillers, crosslinking agents, dissolution promoters, etc. may be added as necessary.
• compositions for forming an underlayer film for lithography were prepared with the compositions shown in the table below.
• the following acid generators, crosslinking agents, and organic solvents were used.
• Acid generator “Ditertiary butyl diphenyliodonium nonafluorobutane sulfonate” manufactured by Midori Kagaku Co., Ltd. (written as “DTDPI” in the table) Pyridinium para-toluenesulfonic acid (written as "PPTS” in the table)
• Crosslinking agent “Nikalac MX270” manufactured by Sanwa Chemical Co., Ltd.
• Etching resistance was evaluated using the following procedure. The above-mentioned etching test was conducted on the lower layer film containing Comparative Example 1-1 (phenol novolac resin), and the etching rate was measured. Next, the etching test was conducted on the lower layer film of each Example and Comparative Example, and the etching rate at that time was measured. Thereafter, the etching resistance of each Example and Comparative Example was evaluated according to the following evaluation criteria using the etching rate of the lower layer film of Comparative Example 1-1 as a standard. ⁇ Evaluation criteria> A: The etching rate was less than -10% compared to the novolak lower layer film. B: The etching rate was ⁇ 10% or more and +5% or less compared to the novolak lower layer film. C: The etching rate was more than +5% compared to the novolak lower layer film.
• Example 20 to 57 Each solution of the lower layer film forming material for lithography prepared in the same manner as in Examples 1-1 to 19-2 above was applied onto a SiO 2 substrate with a film thickness of 300 nm, and heated at 150°C for 60 seconds and further at 400°C. By baking for 120 seconds, a lower layer film with a thickness of 70 nm was formed. An ArF resist solution was applied onto this lower layer film and baked at 130° C. for 60 seconds to form a photoresist layer with a thickness of 140 nm.
• the ArF resist solution contained 5 parts by mass of the compound represented by the following formula (8), 1 part by mass of triphenylsulfonium nonafluorobutanesulfonate, 2 parts by mass of tributylamine, and 92 parts by mass of PGMEA.
• the one prepared by blending was used.
• the compound represented by the following formula (8) includes 4.15 g of 2-methyl-2-methacryloyloxyadamantane, 3.00 g of methacrylloyloxy- ⁇ -butyrolactone, 2.08 g of 3-hydroxy-1-adamantyl methacrylate, and azobis.
• the photoresist layer was exposed to light using an electron beam lithography device (manufactured by Elionix Co., Ltd.; ELS-7500, 50 keV), and baked (PEB) at 115° C. for 90 seconds, and 2.38% by mass of tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds to obtain a positive resist pattern.
• ELS-7500 electron beam lithography device
• PEB baked
• TMAH tetramethylammonium hydroxide
• the results of observing defects in the obtained resist patterns of 55 nm L/S (1:1) and 80 nm L/S (1:1) are shown in the table below.
• “good” means that no major defects were observed in the resist pattern formed with line widths of 55 nm L/S (1:1) and 80 nm L/S (1:1) regarding the resist pattern shape after development.
• "Defective” indicates that a large defect was observed in the resist pattern formed at any line width.
• “resolution” is the minimum line width without pattern collapse and with good rectangularity
• sensitivity is the minimum amount of electron beam energy that can draw a good pattern shape.
• Examples 58-95 A solution of the lower layer film forming material for lithography prepared in the same manner as in Examples 1-1 to 19-2 was applied onto a SiO 2 substrate with a film thickness of 300 nm, and baked at 240°C for 60 seconds and then at 400°C for 120 seconds. By doing so, a lower layer film with a film thickness of 80 nm was formed. A silicon-containing intermediate layer material was applied onto this lower layer film and baked at 200° C. for 60 seconds to form an intermediate layer film with a thickness of 35 nm. Further, the above-mentioned ArF resist solution was applied onto this intermediate layer film and baked at 130° C. for 60 seconds to form a photoresist layer with a thickness of 150 nm.
• the silicon-containing intermediate layer material As the silicon-containing intermediate layer material, a silicon-containing polymer described in ⁇ Synthesis Example 1> of JP-A No. 2007-226170 was used. Next, the photoresist layer was exposed to light using a mask using an electron beam lithography system (manufactured by Elionix Co., Ltd.; ELS-7500, 50 keV), baked at 115°C for 90 seconds (PEB), and 2.38% by mass tetramethylammonium hydroxide was added to the photoresist layer. By developing with a (TMAH) aqueous solution for 60 seconds, a positive resist pattern of 55 nm L/S (1:1) was obtained.
• TMAH TMAH

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Structural Engineering (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Materials For Photolithography (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=89382543

Family Applications (1)

Country Status (3)

Citations (13)

• 2023
  • 2023-06-30 JP JP2024530997A patent/JPWO2024005194A1/ja active Pending
  • 2023-06-30 WO PCT/JP2023/024419 patent/WO2024005194A1/ja not_active Ceased
  • 2023-06-30 TW TW112124633A patent/TW202411187A/zh unknown

Patent Citations (13)

Also Published As

Similar Documents

Legal Events