Protection film formation composition
Patent Information
- Application Number
- JP2023503936
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Priority Date
- 2022-03-03
- Filing Date
- 2022-03-03
- Publication Date
- 2025-03-03
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Current protective films used in semiconductor manufacturing lack sufficient chemical resistance, particularly against ammonia hydrogen peroxide solutions, which can lead to defects during the lithography process.
A protective film forming composition comprising a compound with specific structural units, thermal acid generators or curing agents, and solvents, which forms a film with enhanced chemical resistance and optical properties, applied as a resist underlayer film to improve etching selectivity.
The composition achieves high chemical resistance, desirable dry etching selectivity, and maintains optical parameters, effectively protecting semiconductor substrates during wet etching processes.
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Abstract
Description
Protective film forming composition
[0001] The present invention relates to a composition for forming a protective film that has excellent resistance to a semiconductor wet etching solution, particularly a basic hydrogen peroxide aqueous solution, in a lithography process in semiconductor manufacturing. The present invention also relates to a protective film obtained from the composition, a method for producing a substrate with the protective film, a resist underlayer film using the composition, a method for producing a substrate with a resist pattern, and a method for producing a semiconductor device.
[0002] As the gate insulating film becomes thinner, current leaks between the gate electrode and the substrate, which increases power consumption. ２ High-dielectric-constant films (high-k materials) with higher dielectric constants are used as gate insulating films, and metal gates are used as gate electrodes combined with high-k materials. In the manufacturing process of high-k metal gates, a protective film is formed on a substrate having a TiN film, followed by application of a photoresist and patterning, followed by removal of the TiN by wet etching. However, the protective film used here must be resistant to chemical solutions, particularly to ammonia-hydrogen peroxide solutions (SC-1). Patent Document 1 discloses a protective film-forming composition for semiconductor wet etching solutions, which contains a compound or a polymer thereof containing at least one pair of adjacent hydroxyl groups in the molecule, and a solvent.
[0003] International Patent Application Publication No. 2019 / 124474
[0004] There is a need to develop a technology that provides a protective film with higher chemical resistance, particularly resistance to an ammonia-hydrogen peroxide solution (SC-1).
[0005] The present invention includes the following: [1] (A) A compound having no repeating structural units, comprising a terminal group (A1), a polyvalent group (A2), and a linking group (A3), wherein the terminal group (A1) is bonded only to the linking group (A3), the polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded to the terminal group (A1) on one side and the polyvalent group (A2) on the other side, and may optionally be bonded to another linking group (A3), wherein the terminal group (A1) has any of the structures represented by the following formula (I): [In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and n=1 when X is an ether bond or an ester bond, and n=2 when X is a nitrogen atom.] A protective film-forming composition for a semiconductor wet etching solution, comprising: a compound, wherein the polyvalent group (A2) is a divalent to tetravalent group selected from the group consisting of: -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-, and the linking group (A3) represents an aromatic hydrocarbon group; (B) a thermal acid generator (B-1) and / or a curing agent (B-2); and (C) a solvent. [2] The protective film-forming composition according to [1], wherein the compound (A) is a compound represented by the following formula (II): [In formula (II), Z １ , Z ２ are each independently [In formula (I), * represents Y １ , or Y ２ X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. １ , Y ２ each independently represents an aromatic hydrocarbon group; １ , X ２ are each independently -Y １ -Z １ or -Y ２ -Z ２wherein n1 and n2 each independently represent an integer of 0 to 4, provided that either is 1 or greater, m1 and m2 each independently represent 0 or 1, and Q represents a divalent to tetravalent group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-.] [3] The compound (A) is represented by the following formula (III): [In formula (III), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring. X represents an ether bond, an ester bond, or a nitrogen atom, and n=1 when X is an ether bond or an ester bond, and n=2 when X is a nitrogen atom.] [4] The protective film-forming composition according to any one of [1] to [3], wherein the compound (A) has a weight-average molecular weight of 300 or more and 1,500 or less. [5] The protective film-forming composition according to any one of [1] to [4], wherein the compound (A), component (B), and solvent (C) do not contain a material containing one or more aromatic groups containing two or more substituents each containing a hydroxyl, thiol, and / or amine moiety. [7] The protective film-forming composition according to any one of [1] to [6], wherein the compound (A) has two or more linking groups (A3). [8] The protective film-forming composition according to any one of [1] to [7], wherein the component (B) includes a curing agent (B-2) selected from the group consisting of phenolic curing agents, amide curing agents, amine curing agents, imidazoles, acid anhydride curing agents, and organic phosphines. [9] The protective film-forming composition according to any one of [1] to [8], further including (D) a compound having one phenolic hydroxy group or a polymer having a unit structure having one phenolic hydroxy group.
[10] A protective film, which is a baked product of a coating film made from the protective film-forming composition according to any one of [1] to [9].
[0006]
[11] (A) A compound having no repeating structural unit, comprising a terminal group (A1), a polyvalent group (A2), and a linking group (A3), wherein the terminal group (A1) is bonded only to the linking group (A3), the polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded to the terminal group (A1) on one side and the polyvalent group (A2) on the other side, and may optionally be bonded to another linking group (A3), wherein the terminal group (A1) has any of the structures of the following formula (I): [In formula (I), * represents a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and n=1 when X is an ether bond or an ester bond, and n=2 when X is a nitrogen atom.] The polyvalent group (A2) is a divalent to tetravalent group selected from the group consisting of: -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-, and the linking group (A3) represents an aromatic hydrocarbon group; (B) a thermal acid generator (B-1) and / or a curing agent (B-2); and (C) a solvent.
[12] The resist underlayer film forming composition according to
[11] , wherein the compound (A) is a compound represented by the following formula (II): [In formula (II), Z １ , Z ２ are each independently [In formula (I), * represents Y １ , or Y ２ X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. １ , Y ２ each independently represents an aromatic hydrocarbon group; １ , X ２ are each independently -Y １ -Z １ or -Y ２ -Z ２wherein n1 and n2 each independently represent an integer of 0 to 4, provided that either is 1 or greater, m1 and m2 each independently represent 0 or 1, and Q represents a divalent to tetravalent group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-.]
[13] The compound (A) is represented by the following formula (III): [In formula (III), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring. X represents an ether bond, an ester bond, or a nitrogen atom, and n=1 when X is an ether bond or an ester bond, and n=2 when X is a nitrogen atom.].
[14] The resist underlayer film forming composition according to any one of items
[11] to
[13] , wherein the compound (A) has a weight average molecular weight of 300 or more and 1,500 or less.
[15] The resist underlayer film forming composition according to any one of items
[11] to
[14] , wherein the compound (A), component (B), and solvent (C) each do not contain a material containing one or more aromatic groups having two or more substituents each containing a hydroxyl, a thiol, and / or an amine moiety.
[16] The resist underlayer film forming composition according to any one of items
[11] to
[15] , wherein each of the compound (A), component (B), and solvent (C) does not contain a material containing one or more aromatic groups having two or more substituents each containing a hydroxyl, a thiol, and / or an amine moiety.
[17] The resist underlayer film-forming composition according to any one of items
[11] to
[16] , wherein the compound (A) has two or more linking groups (A3).
[18] The resist underlayer film-forming composition according to any one of items
[11] to
[17] , wherein the component (B) includes a curing agent (B-2) selected from the group consisting of a phenolic curing agent, an amide curing agent, an amine curing agent, an imidazole, an acid anhydride curing agent, and an organic phosphine.
[19] The resist underlayer film-forming composition according to any one of items
[11] to
[18] , further including (D) a compound having one phenolic hydroxy group, or a polymer having a unit structure having one phenolic hydroxy group.
[20] A resist underlayer film, which is a baked product of a coating film comprising the resist underlayer film-forming composition according to any one of items
[11] to
[19] .
[0007]
[21] A method for producing a substrate with a protective film, the method comprising the steps of applying the protective film-forming composition according to any one of [1] to [9] onto a semiconductor substrate having a step and baking the composition to form a protective film.
[22] A method for producing a substrate with a resist pattern, the method comprising the steps of applying the protective film-forming composition according to any one of [1] to [9] or the resist underlayer film-forming composition according to any one of
[11] to
[19] onto a semiconductor substrate and baking the composition to form a protective film as a resist underlayer film, forming a resist film on the protective film, and then exposing and developing the resist film to form a resist pattern.
[23] A method for producing a semiconductor device, the method comprising the steps of forming a protective film on a semiconductor substrate, the surface of which may have an inorganic film formed thereon, using the protective film-forming composition according to any one of [1] to [9], forming a resist pattern on the protective film, dry-etching the protective film using the resist pattern as a mask to expose the surface of the inorganic film or the semiconductor substrate, and wet-etching and cleaning the inorganic film or the semiconductor substrate using a semiconductor wet etching solution using the protective film after dry etching as a mask.
[24] A method for manufacturing a semiconductor device, comprising the steps of forming a resist underlayer film on a semiconductor substrate, optionally having an inorganic film formed on its surface, using the resist underlayer film-forming composition according to any one of
[11] to
[19] , forming a resist pattern on the resist underlayer film, dry-etching the resist underlayer film using the resist pattern as a mask to expose a surface of the inorganic film or the semiconductor substrate, and etching the inorganic film or the semiconductor substrate using the resist underlayer film after dry etching as a mask.
[0008] The protective film-forming composition according to the present invention can form a protective film that exhibits high chemical resistance, good optical parameters, and a desirable dry etching selectivity in the lithography process of semiconductor manufacturing.
[0009] <Composition> The protective film-forming composition for a semiconductor wet etching liquid according to the present invention comprises: (A) a compound having no repeating structural unit, comprising a terminal group (A1), a polyvalent group (A2), and a linking group (A3), wherein the terminal group (A1) is bonded only to the linking group (A3), the polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded to the terminal group (A1) on one side and the polyvalent group (A2) on the other side, and may optionally be bonded to another linking group (A3), and the terminal group (A1) has any of structures represented by the following formula (I): [In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2.] The polyvalent group (A2) is a divalent to tetravalent group selected from the group consisting of: -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-, and the linking group (A3) represents an aromatic hydrocarbon group, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent.
[0010] The protective film-forming composition for a semiconductor wet etching solution according to the present invention can also be used as a resist underlayer film-forming composition, as will be described later.
[0011] <Compound (A)> The phrase "having no repeating structural units" means excluding so-called polymers that have repeating structural units, such as polyolefins, polyesters, polyamides, poly(meth)acrylates, etc. Preferably, the weight average molecular weight of compound (A) is 300 or more and 1,500 or less.
[0012] The "bond" between the terminal group (A1), the polyvalent group (A2), and the linking group (A3) means a chemical bond, and usually means a covalent bond, but does not prevent it from being an ionic bond.
[0013] The polyvalent group (A2) is a divalent to tetravalent group.
[0014] Therefore, the aliphatic hydrocarbon group in the definition of the polyvalent group (A2) is a divalent to tetravalent aliphatic hydrocarbon group. Non-limiting examples of divalent aliphatic hydrocarbon groups include methylene, ethylene, n-propylene, isopropylene, cyclopropylene, n-butylene, isobutylene, s-butylene, t-butylene, cyclobutylene, 1-methylcyclopropylene, 2-methylcyclopropylene, n-pentylene, 1-methyl-n-butylene, 2-methyl-n-butylene, 3-methyl-n-butylene, 1,1-dimethyl-n-propylene, 1,2-dimethyl-n-propylene, and 1,3-dimethyl-n-propylene. Methyl-n-propylene group, 2,2-dimethyl-n-propylene, 1-ethyl-n-propylene group, cyclopentylene group, 1-methyl-cyclobutylene group, 2-methyl-cyclobutylene group, 3-methyl-cyclobutylene group, 1,2-dimethyl-cyclopropylene group, 2,3-dimethyl-cyclopropylene group, 1-ethyl-cyclopropylene group, 2-ethyl-cyclopropylene group, n-hexylene group, 1-methyl-n-pentylene group, 2-methyl-n-pentylene group, 3-methyl-n -pentylene group, 4-methyl-n-pentylene group, 1,1-dimethyl-n-butylene group, 1,2-dimethyl-n-butylene group, 1,3-dimethyl-n-butylene group, 2,2-dimethyl-n-butylene group, 2,3-dimethyl-n-butylene group, 3,3-dimethyl-n-butylene group, 1-ethyl-n-butylene group, 2-ethyl-n-butylene group, 1,1,2-trimethyl-n-propylene group, 1,2,2-trimethyl-n-propylene group, 1-ethyl-1-methyl-n-propylene group, 1-ethyl-2-methyl-n-propylene group, cyclohexylene group, 1-methyl-cyclopentylene group, 2-methyl-cyclopentylene group, 3-methyl-cyclopentylene group, 1-ethyl-cyclobutylene group, 2-ethyl-cyclobutylene group, 3-ethyl-cyclobutylene group, 1,2-dimethyl-cyclobutylene group, 1,3-dimethyl-cyclobutylene group, 2,2-dimethyl-cyclobutylene group, 2,3-dimethyl-cyclobutylene group, 2,4-dimethyl-cyclobutylene group, 3,Examples of alkylene groups include a 3-dimethyl-cyclobutylene group, a 1-n-propyl-cyclopropylene group, a 2-n-propyl-cyclopropylene group, a 1-isopropyl-cyclopropylene group, a 2-isopropyl-cyclopropylene group, a 1,2,2-trimethyl-cyclopropylene group, a 1,2,3-trimethyl-cyclopropylene group, a 2,2,3-trimethyl-cyclopropylene group, a 1-ethyl-2-methyl-cyclopropylene group, a 2-ethyl-1-methyl-cyclopropylene group, a 2-ethyl-2-methyl-cyclopropylene group, a 2-ethyl-3-methyl-cyclopropylene group, an n-heptylene group, an n-octylene group, an n-nonylene group, and an n-decanylene group.
[0015] A hydrogen atom at any position of these groups can be removed and converted into a bond to give a trivalent or tetravalent group.
[0016] Examples of the aromatic hydrocarbon group having less than 10 carbon atoms in the definition of the polyvalent group (A2) include benzene, toluene, xylene, mesitylene, cumene, styrene, and indene.
[0017] Examples of the aliphatic hydrocarbon group that can be combined with the aromatic hydrocarbon group having less than 10 carbon atoms include, in addition to the above alkylene groups, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a cyclopropyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, a cyclobutyl group, a 1-methylcyclopropyl group, a 2-methylcyclopropyl group, an n-pentyl group, a 1-methyln-butyl group, a 2-methyln-butyl group, a 3-methyln-butyl group, a 1,1-dimethyln-propyl group, a 1,2-dimethyln-propyl group, a 2,2-dimethyl -n-propyl group, 1-ethyl-n-propyl group, cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-di Methyl-n-butyl group, 2,2-dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclohexyl group cyclobutyl group, 3-ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2,Examples of alkyl groups include a 3-trimethyl-cyclopropyl group, a 1-ethyl-2-methyl-cyclopropyl group, a 2-ethyl-1-methyl-cyclopropyl group, a 2-ethyl-2-methyl-cyclopropyl group, a 2-ethyl-3-methyl-cyclopropyl group, and a decyl group.
[0018] In the definition of the polyvalent group (A2), either the aromatic hydrocarbon group or the aliphatic hydrocarbon group having less than 10 carbon atoms may be bonded to the linking group (A3).
[0019] Examples of the aromatic hydrocarbon group having 10 or more carbon atoms in the definition of the polyvalent group (A2) include naphthalene, azulene, anthracene, phenanthrene, naphthacene, triphenylene, pyrene, and chrysene.
[0020] The aromatic hydrocarbon group having 10 or more carbon atoms in the definition of the polyvalent group (A2) is preferably bonded to the linking group (A3) via —O—.
[0021] Examples of the aromatic hydrocarbon group in the definition of the linking group (A3) include the above-mentioned aromatic hydrocarbon groups having less than 10 carbon atoms and the above-mentioned aromatic hydrocarbon groups having 10 or more carbon atoms.
[0022] Preferably, the compound (A) has two or more linking groups (A3).
[0023] Preferably, the compound (A) is represented by the following formula (II): [In formula (II), Z １ , Z ２ are each independently [In formula (I), * represents Y １ , or Y ２ X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. １ , Y ２ each independently represents an aromatic hydrocarbon group; １ , X ２ are each independently -Y １ -Z １ or -Y ２ -Z ２n1 and n2 each independently represent an integer of 0 to 4, provided that either one is 1 or greater; m1 and m2 each independently represent 0 or 1; and Q represents a divalent to tetravalent group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-.]
[0024] In formula (II), Z １ , Z ２ represents the terminal group (A1), Q represents the polyvalent group (A2), Y １ , Y ２ correspond to the above-mentioned linking group (A3), and the explanations and examples thereof are incorporated herein by reference.
[0025] Preferably, compound (A) is represented by the following formula (III): [In formula (III), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring. X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2].
[0026] <(B) Thermal Acid Generator (B-1) and / or Curing Agent (B-2)> The protective film-forming composition of the present invention further contains (B) a thermal acid generator (B-1) and / or a curing agent (B-2).
[0027] <Thermal Acid Generator (B-1)> Examples of the thermal acid generator include pyridinium p-toluenesulfonate, pyridinium trifluoromethanesulfonate, pyridinium p-phenolsulfonate, K-PURE (registered trademark) CXC-1612, CXC-1614, TAG-2172, TAG-2179, TAG-2678, and TAG2689 (all manufactured by King Industries), and SI-45, SI-60, SI-80, SI-100, SI-110, and SI-150 (all manufactured by Sanshin Chemical Industry Co., Ltd.).
[0028] These thermal acid generators can be used alone or in combination of two or more.
[0029] When the protective film-forming composition of the present invention contains a thermal acid generator, the lower limit of its content is usually 0.0001 mass %, preferably 0.01 mass %, and more preferably 0.1 mass %, based on the total solid content of the protective film-forming composition, and the upper limit of its content is usually 20 mass %, preferably 15 mass %, and more preferably 10 mass %, based on the total solid content of the protective film-forming composition.
[0030] <Curing Agent (B-2)> The curing agent used in the protective film-forming composition of the present invention is not particularly limited, and any commonly known curing agent can be used. Preferably, the curing agent is selected from the group consisting of phenol-based curing agents, amide-based curing agents, amine-based curing agents, imidazoles, acid anhydride-based curing agents, and organic phosphines.
[0031] [Phenol-based curing agent] Examples of phenol-based curing agents include bisphenol A, bisphenol F, 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl ether, 1,4-bis(4-hydroxyphenoxy)benzene, 1,3-bis(4-hydroxyphenoxy)benzene, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, poly-p-hydroxystyrene, hydroquinone, resorcinol, catechol, t-butylcatechol, t- Butyl hydroquinone, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated products or polyallylated products of the above dihydroxynaphthalenes, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak, allylated pyrogallol, and the like.
[0032] [Amide-Based Curing Agent] Examples of the amide-based curing agent include dicyandiamide and its derivatives, polyamide resins, and the like.
[0033] [Amine-Based Curing Agent] Examples of the amine-based curing agent include aliphatic amines, polyether amines, alicyclic amines, and aromatic amines. Examples of the aliphatic amines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminopropane, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, bis(hexamethylene)triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-hydroxyethylethylenediamine, and tetra(hydroxyethyl)ethylenediamine. Examples of the polyetheramines include triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis(propylamine), polyoxypropylene diamine, and polyoxypropylene triamines. Examples of alicyclic amines include isophoronediamine, methacenediamine, N-aminoethylpiperazine, bis(4-amino-3-methyldicyclohexyl)methane, bis(aminomethyl)cyclohexane, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, and norbornenediamine. Examples of aromatic amines include tetrachloro-p-xylylenediamine, m-xylylenediamine, p-xylylenediamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisole, 2,4-toluenediamine, 2,4-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diamino-1,2-diphenylethane, 2,4-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, m-aminophenol, m-aminobenzylamine, benzyldimethylamine, 2-dimethylaminomethylphenol, triethanolamine, methylbenzylamine, α-(m-aminophenyl)ethylamine, α-(p-aminophenyl)ethylamine, diaminodiethyldimethyldiphenylmethane, and α,α'-bis(4-aminophenyl)-p-diisopropylbenzene.
[0034] [Imidazoles] Examples of imidazoles include 2-phenylimidazole, 2-ethyl-4(5)-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins with the above imidazoles.
[0035] [Acid Anhydride Curing Agent] Examples of the acid anhydride curing agent include acid anhydrides and modified acid anhydrides.
[0036] Examples of acid anhydrides include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, dodecenylsuccinic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic anhydride, poly(ethyloctadecanedioic) anhydride, poly(phenylhexadecanedioic) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhimic anhydride, tetrahydrophthalic anhydride, and trialkyltetrahydrophthalic anhydride. Acid anhydrides, methylcyclohexene dicarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bistrimellitate dianhydride, HET acid anhydride, Nadic acid anhydride, methylnadic acid anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid dianhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid dianhydride, and the like.
[0037] Examples of modified acid anhydrides include those obtained by modifying the above-mentioned acid anhydrides with glycol. Examples of glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol, and neopentyl glycol; and polyether glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. Furthermore, copolymer polyether glycols of two or more of these glycols and / or polyether glycols can also be used. In addition, in the modified acid anhydrides, it is preferable to modify them with 0.4 moles or less of glycol per mole of acid anhydride.
[0038] [Organic Phosphines] Examples of organic phosphines include tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, and phenylphosphine. Examples of phosphonium salts include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium ethyltriphenylborate, and tetrabutylphosphonium tetrabutylborate. Examples of tetraphenylboron salts include 2-ethyl-4-methylimidazole tetraphenylborate and N-methylmorpholine tetraphenylborate.
[0039] [Other Curing Agents] Examples of other curing agents include mercaptan-based curing agents, tertiary amines, phosphonium salts, tetraphenylboron salts, organic acid dihydrazides, boron halide amine complexes, isocyanate-based curing agents, and blocked isocyanate-based curing agents.
[0040] These curing agents can be used alone or in combination of two or more.
[0041] When the protective film-forming composition of the present invention contains a curing agent, the lower limit of its content is usually 0.0001 mass %, preferably 0.01 mass %, and more preferably 0.1 mass %, based on the total solid content of the protective film-forming composition, and the upper limit of its content is usually 50 mass %, preferably 40 mass %, and more preferably 30 mass %, based on the total solid content of the protective film-forming composition.
[0042] <Solvent (C)> The protective film-forming composition of the present invention can be prepared by dissolving the above-described components in a solvent, preferably an organic solvent, and is used in the form of a homogeneous solution.
[0043] The organic solvent for the protective film-forming composition of the present invention is not particularly limited, as long as it is an organic solvent that can dissolve the components (A) and (B) and other optional solid components. In particular, since the protective film-forming composition of the present invention is used in the form of a homogeneous solution, it is recommended to use an organic solvent that is commonly used in lithography processes in combination with the composition, taking into account its coating performance.
[0044] Examples of the organic solvent 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, and cyclohexanone. Examples of the solvent include cyclopentane, cycloheptanone, 4-methyl-2-pentanol, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, ethyl ethoxyacetate, 2-hydroxyethyl acetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, methoxycyclopentane, anisole, γ-butyrolactone, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used alone or in combination of two or more.
[0045] Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, cyclohexanone, etc. are preferred, with propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate being particularly preferred.
[0046] The solids content of the protective film-forming composition according to the present invention is usually 0.1 to 70% by mass, preferably 0.1 to 60% by mass. The solids content is the content of all components excluding the solvent from the protective film-forming composition. The proportion of compound (A) in the solids content is preferably 1 to 100% by mass, 1 to 99.9% by mass, 50 to 99.9% by mass, 50 to 95% by mass, and 50 to 90% by mass, in that order.
[0047] <Component (D)> The protective film-forming composition of the present invention can further contain (D) a compound having one phenolic hydroxy group or a polymer having a unit structure having one phenolic hydroxy group. The term "compound having one phenolic hydroxy group or polymer having a unit structure having one phenolic hydroxy group" excludes compounds or polymers having a phenolic hydroxy group, such as catechol. The compound having one phenolic hydroxy group or the polymer having a unit structure having one phenolic hydroxy group is not particularly limited as long as it does not impair the effects of the present invention.
[0048] The weight average molecular weight of the compound having one phenolic hydroxy group or the polymer having a unit structure having one phenolic hydroxy group is not particularly limited, and is, for example, 300 to 50,000, or 1,000 to 50,000.
[0049] The polymer having a unit structure having one phenolic hydroxy group preferably contains a unit structure represented by the following formula (3-1):
[0050]
[0051] (In the formula, T ４ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may be substituted with a halogeno group. ４ represents a halogeno group, a carboxy group, a nitro group, a cyano group, a methylenedioxy group, an acetoxy group, a methylthio group, an alkoxy group having 1 to 9 carbon atoms, an amino group which may be substituted with an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 10 carbon atoms which may be substituted with a hydroxy group or a halogeno group. r4 represents an integer of 0 to 3. n7 represents an integer of 0 to 2. a is 1.
[0052] The halogeno group includes fluorine, chlorine, bromine and iodine.
[0053] Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a cyclopropyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, a cyclobutyl group, a 1-methyl-cyclopropyl group, a 2-methyl-cyclopropyl group, an n-pentyl group, a 1-methyl-n-butyl group, a 2-methyl-n-butyl group, a 3-methyl-n-butyl group, a 1,1-dimethyl-n-propyl group, a 1,2-dimethyl-n-propyl group, a 2,2-dimethyl-n-propyl group, and a 1-ethyl-n-propyl group. Cyclopentyl group, 1-methylcyclobutyl group, 2-methylcyclobutyl group, 3-methylcyclobutyl group, 1,2-dimethylcyclopropyl group, 2,3-dimethylcyclopropyl group, 1-ethylcyclopropyl group, 2-ethylcyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group, 2,2- Dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclobutyl group, 3 -ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2,Examples include a 3-trimethyl-cyclopropyl group, a 1-ethyl-2-methyl-cyclopropyl group, a 2-ethyl-1-methyl-cyclopropyl group, a 2-ethyl-2-methyl-cyclopropyl group, a 2-ethyl-3-methyl-cyclopropyl group, and a decyl group.
[0054] Examples of the alkoxy group having 1 to 9 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a tert-butoxy group, a sec-butoxy group, an n-pentoxy group, a neopentoxy group, an n-hexyloxy group, an isohexyloxy group, and a 3-methylpentoxy group.
[0055] The polymer having a unit structure having one phenolic hydroxy group preferably has at least three repeating unit structures.
[0056] The polymer having a unit structure having one phenolic hydroxy group may be a polymer containing one type of unit structure represented by formula (3-1), or may be a copolymer containing two or more types.
[0057] Specific examples of the polymer having a unit structure having one phenolic hydroxy group include polymers containing the unit structures shown below.
[0058]
[0059] The protective film-forming composition for a semiconductor wet etching solution according to the present invention preferably does not contain a novolak resin, and each of the compound (A), the component (B), and the solvent (C) preferably does not contain a material containing one or more aromatic groups having two or more substituents each containing a hydroxyl, a thiol, and / or an amine moiety.
[0060] <Protective Film, Resist Underlayer Film, and Methods for Producing a Substrate with a Protective Film / Substrate with a Resist Pattern, and a Semiconductor Device> Hereinafter, methods for producing a substrate with a protective film / substrate with a resist pattern, and methods for producing a semiconductor device using the protective film-forming composition / resist underlayer film-forming composition according to the present invention will be described.
[0061] The substrate with a protective film / substrate with a resist pattern according to the present invention can be produced by applying the above-mentioned protective film-forming composition / resist underlayer film-forming composition onto a semiconductor substrate and baking it.
[0062] Examples of semiconductor substrates to which the protective film-forming composition / resist underlayer film-forming composition of the present invention can be applied include silicon wafers, germanium wafers, and semiconductor wafers such as gallium arsenide, indium phosphide, titanium nitride, gallium nitride, indium nitride, aluminum nitride, and aluminum oxide.
[0063] When a semiconductor substrate having an inorganic film formed on its surface is used, the inorganic film can be formed by, for example, ALD (atomic layer deposition), CVD (chemical vapor deposition), reactive sputtering, ion plating, vacuum deposition, or spin coating (spin-on glass: SOG). Examples of the inorganic film include low-temperature oxide films, polysilicon films, silicon oxide films, silicon nitride films, silicon oxynitride films, BPSG (Boro-Phospho Silicate Glass) films, titanium nitride films, titanium oxynitride films, tungsten nitride films, gallium nitride films, aluminum oxide, hafnium oxide, tantalum, tantalum nitride, and gallium arsenide films. The semiconductor substrate may be a stepped substrate having vias (holes), trenches (grooves), or the like formed therein. For example, a via has a substantially circular shape when viewed from above, with a diameter of, for example, 2 nm to 20 nm and a depth of, for example, 50 nm to 500 nm, and a trench has, for example, a groove (recess in a substrate) with a width of, for example, 1 nm to 20 nm and a depth of, for example, 50 nm to 500 nm. Because the protective film-forming composition / resist underlayer film-forming composition of the present invention has a small weight-average molecular weight and average particle size of the compounds contained therein, the composition can be used to fill uneven substrates such as those described above without defects such as voids (gaps). The absence of defects such as voids is an important characteristic for subsequent processes in semiconductor manufacturing (wet etching / dry etching of the semiconductor substrate, resist pattern formation).
[0064] The protective film-forming composition / resist underlayer film-forming composition of the present invention is applied to such a semiconductor substrate using an appropriate application method such as a spinner or coater. The composition is then baked using a heating means such as a hot plate to form a protective film / resist underlayer film. Baking conditions are appropriately selected from a bake temperature of 100°C to 400°C and a bake time of 0.3 minutes to 60 minutes. Preferably, the bake temperature is 120°C to 350°C and the bake time is 0.5 minutes to 30 minutes, more preferably, the bake temperature is 150°C to 300°C and the bake time is 0.8 minutes to 10 minutes. The thickness of the protective film / resist underlayer film formed is, for example, 0.001 μm to 10 μm, preferably 0.002 μm to 1 μm, and more preferably 0.005 μm to 0.5 μm. Baking temperatures lower than the above ranges may result in insufficient crosslinking, making it difficult for the resulting protective film / resist underlayer film to exhibit resistance to resist solvents or basic hydrogen peroxide aqueous solutions. On the other hand, if the baking temperature is higher than the above range, the protective film / resist underlayer film may be decomposed by heat.
[0065] Exposure is performed through a mask (reticle) to form a predetermined pattern, and for example, i-line, KrF excimer laser, ArF excimer laser, EUV (extreme ultraviolet), or EB (electron beam) is used. An alkaline developer is used for development, with the development temperature appropriately selected from 5°C to 50°C and the development time appropriately selected from 10 seconds to 300 seconds. Examples of alkaline developers that can be used include aqueous solutions of inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-butylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline; and cyclic amines such as pyrrole and piperidine. Furthermore, the aqueous solutions of the alkalis can also be used by adding appropriate amounts of alcohols such as isopropyl alcohol and surfactants such as nonionic surfactants. Among these, preferred developers are quaternary ammonium salts, more preferably tetramethylammonium hydroxide and choline. Furthermore, surfactants and the like can be added to these developers. Alternatively, development can be carried out with an organic solvent such as butyl acetate instead of an alkaline developer to develop the portions of the photoresist where the alkaline dissolution rate is not improved.
[0066] Next, the protective film / resist underlayer film is dry-etched using the formed resist pattern as a mask. In this process, if the inorganic film is formed on the surface of the semiconductor substrate used, the surface of the inorganic film is exposed. In contrast, if the inorganic film is not formed on the surface of the semiconductor substrate used, the surface of the semiconductor substrate is exposed. The protective film / resist underlayer film of the present application can also be used in a lithography process in which an upper layer of resist is combined with another material (e.g., a resist layer with a silicon oxide film underneath).
[0067] Furthermore, the protective film / resist underlayer film after dry etching (if a resist pattern remains on the protective film / resist underlayer film, the resist pattern is also used) is used as a mask to perform wet etching using a semiconductor wet etching solution, thereby forming a desired pattern.
[0068] As the wet etching solution for semiconductors, a general chemical solution for etching semiconductor wafers can be used, and for example, either an acidic substance or a basic substance can be used.
[0069] Examples of substances that exhibit acidity include hydrogen peroxide, hydrofluoric acid, ammonium fluoride, acidic ammonium fluoride, ammonium hydrogen fluoride, buffered hydrofluoric acid, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, and mixtures thereof.
[0070] Examples of substances that exhibit basicity include basic hydrogen peroxide solution, which is obtained by mixing ammonia, sodium hydroxide, potassium hydroxide, sodium cyanide, potassium cyanide, or an organic amine such as triethanolamine with hydrogen peroxide solution to make the pH basic. A specific example is SC-1 (ammonia-hydrogen peroxide solution). Other substances that can make the pH basic, such as a solution obtained by mixing urea with hydrogen peroxide solution and heating to cause thermal decomposition of the urea to generate ammonia, which ultimately makes the pH basic, can also be used as a wet etching chemical.
[0071] Among these, acidic hydrogen peroxide solution or basic hydrogen peroxide solution is preferred.
[0072] These chemical solutions may contain additives such as surfactants.
[0073] The temperature at which the semiconductor wet etching solution is used is preferably 25° C. to 90° C., and more preferably 40° C. to 80° C. The wet etching time is preferably 0.5 to 30 minutes, and more preferably 1 to 20 minutes.
[0074] The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples.
[0075] The weight-average molecular weights of the compounds shown in Examples 1 to 4 and Synthesis Example 1 below in this specification are the results of measurements by gel permeation chromatography (hereinafter abbreviated as GPC). For the measurements, a GPC device manufactured by Tosoh Corporation was used, and the measurement conditions etc. are as follows.
[0076] GPC columns: TSKgel guard column SuperMP(HZ)-N, TSKgel SuperMultiporeHZ-N(P009), TSKgel SuperMultiporeHZ-N(P0010) (manufactured by Tosoh Corporation) Column temperature: 40°C Solvent: tetrahydrofuran (THF) Flow rate: 0.35 ml / min Standard sample: polystyrene (manufactured by Tosoh Corporation)
[0077] Example 1 To 3.56 g of tetraphenylolethane tetraglycidyl ether (manufactured by Nippon Kayaku Co., Ltd., product name 1031S) (weight average molecular weight: 1,033), 0.036 g of K-PURE (registered trademark) TAG-2689 (product of King Industries) as a thermal acid generator, 77.12 g of propylene glycol monomethyl ether acetate, and 19.28 g of propylene glycol monomethyl ether were added to form a solution. The solution was filtered using a polyethylene microfilter with a pore size of 0.02 μm to prepare a protective film-forming composition.
[0078]
[0079] Example 2 0.018 g of K-PURE (registered trademark) TAG-2689 (a product of King Industries) as a thermal acid generator, 33.56 g of propylene glycol monomethyl ether acetate, and 9.64 g of propylene glycol monomethyl ether were added to 1.78 g of 2-[4-(2,3-epoxypropoxy)phenyl]-2-(4-[1,1-bis[4-([2,3-epoxypropoxy]phenyl)ethyl]phenyl]propane (manufactured by Mitsubishi Chemical Corporation, product name NC-6000) (weight average molecular weight: 548) to form a solution. The solution was filtered using a polyethylene microfilter having a pore size of 0.02 μm, thereby preparing a protective film-forming composition.
[0080]
[0081] Example 3 0.029 g of K-PURE (registered trademark) TAG-2689 (a product of King Industries) as a thermal acid generator, 61.70 g of propylene glycol monomethyl ether acetate, and 15.42 g of propylene glycol monomethyl ether were added to 2.85 g of a commercially available epoxy resin (manufactured by DIC Corporation, product name EPICLON HP-6000) (weight average molecular weight: 361, containing a compound of the following structural formula) to form a solution. The solution was filtered using a polyethylene microfilter with a pore size of 0.02 μm to prepare a protective film-forming composition.
[0082]
[0083] Example 4 0.83 g of 2-[4-(2,3-epoxypropoxy)phenyl]-2-(4-[1,1-bis[4-([2,3-epoxypropoxy]phenyl)ethyl]phenyl]propane (manufactured by Mitsubishi Chemical Corporation, product name NC-6000) (weight average molecular weight: 548), 0.28 g of VP-2500 (manufactured by Nippon Soda Co., Ltd., corresponding to formula (A), weight average molecular weight: 3,687) (30 mass % PGMEA solution) were added to a solution of K-PURE (registered trademark) TAG-2689 (King To a solution, 0.083 g of propylene glycol monomethyl ether acetate (manufactured by DIC Corporation) (a product of DIC Industries), 0.083 g of R-40-LM (a 1% by mass PGMEA solution), 15.18 g of propylene glycol monomethyl ether acetate, and 6.62 g of propylene glycol monomethyl ether were added. The solution was filtered using a polyethylene microfilter with a pore size of 0.02 μm to prepare a protective film-forming composition.
[0084]
[0085] Synthesis Example 1 A solution of 5.50 g of glycerin monomethacrylate (product name: Blenmer GLM, manufactured by NOF Corporation), 5.09 g of 5-vinylbenzo[d][1,3]dioxole (manufactured by Cool Pharm LTD.), 0.66 g of 2,2'-azobis(isobutyronitrile) (manufactured by Tokyo Chemical Industry Co., Ltd.), and 35.99 g of propylene glycol monomethyl ether was added to a dropping funnel and added dropwise to a reaction flask containing 9.00 g of propylene glycol monomethyl ether at 100°C under a nitrogen atmosphere, followed by heating and stirring for 17 hours. To the resulting solution, 11 g of a cation exchange resin (product name: Dowex (registered trademark) 550A, manufactured by Muromachi Technos Co., Ltd.) and 11 g of an anion exchange resin (product name: Amberlite (registered trademark) 15JWET, manufactured by Organo Corporation) were added, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. The ion exchange resin was separated to obtain a resin solution corresponding to formula (B), which had a weight average molecular weight (Mw) of 10,800 as measured by GPC in terms of polystyrene.
[0086]
[0087] Comparative Example 1 To 6.6 g of the resin solution (solid content: 17.4 wt %) obtained in Synthesis Example 1, 0.06 g of pyridinium trifluoromethanesulfonate (manufactured by ADEKA Corporation) as a crosslinking acid catalyst, 0.001 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, fluorine-based surfactant), 11.5 g of propylene glycol monomethyl ether, and 1.9 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a protective film-forming composition.
[0088] (Formation of coating film) The protective film-forming compositions prepared in Examples 1 to 4 and the film-forming composition prepared in Comparative Example 1 were applied by spin coating to a silicon substrate having a titanium nitride film formed on its surface, and baked at 250°C for 60 seconds to form a coating film with a thickness of 100 nm.
[0089] (Test for resistance to basic hydrogen peroxide aqueous solution) Coating films formed on silicon substrates having titanium nitride films formed on their surfaces using the protective film-forming compositions prepared in Examples 1 to 4 and the film-forming composition prepared in Comparative Example 1 were immersed in a basic hydrogen peroxide aqueous solution having the composition shown in Table 1 below for 4 minutes at the temperature shown in the same table, and then washed with water and dried, after which the state of the coating film was visually observed. The results are shown in Table 2 below. In Table 2, "◯" indicates a state in which no peeling was observed in the coating film even after 4 minutes of treatment, and "X" indicates a state in which peeling was observed in part or all of the coating film after 4 minutes of treatment.
[0090]
[0091]
[0092] The results in the above table demonstrate that the coating films prepared using the protective film-forming compositions prepared in Examples 1 to 3 have sufficient resistance to a basic hydrogen peroxide aqueous solution. That is, it was found that these coating films can serve as protective films against a basic hydrogen peroxide aqueous solution. On the other hand, it was found that the coating film prepared using the film-forming composition prepared in Comparative Example 1 was insufficient as a protective film against a basic hydrogen peroxide aqueous solution.
[0093] (Optical Parameter Test) The protective film-forming compositions prepared in Examples 1 to 4 and Comparative Example 1 were each applied to a silicon wafer using a spinner. The protective film-forming compositions were baked on a hot plate at 250°C for 1 minute to form resist underlayer films (film thickness: 50 nm). The n value (refractive index) and k value (extinction coefficient or absorption coefficient) at wavelengths of 193 nm and 193 nm were measured using a spectroscopic ellipsometer (J.A. Woollam, VUV-VASE VU-302). The results are shown in Table 3.
[0094] (Measurement of Dry Etching Rate) Each of the protective film-forming compositions prepared in Examples 1 to 4 and Comparative Example 1 was applied to a silicon wafer using a spin coater. The coating was baked on a hot plate at 250°C for 1 minute to form a resist underlayer film. Then, a dry etching apparatus (RIE-10NR) manufactured by Samco Corporation was used, and N 2 was used as the dry etching gas. ２(200sccm), O ２ The dry etching rate (amount of film thickness reduction per unit time) was measured under the conditions of using a SiO 2 film (10 sccm) and RF (60 W).
[0095] The dry etching rates of the protective film-forming compositions prepared in Examples 1 to 4 were compared with the dry etching rate of the protective film-forming composition prepared in Comparative Example 1. Table 3 shows the dry etching rate of the protective film-forming composition of each Example as a "selectivity" when the dry etching rate of Comparative Example 1 was set to 1.00.
[0096]
[0097] From the above results, it can be said that the dry etching rates of the protective film-forming compositions prepared in Examples 1 to 4 according to the present invention are smaller than the dry etching rate of the protective film-forming composition prepared in Comparative Example 1, and that under the above dry etching conditions, the protective film of the present application has etching resistance.
[0098] The protective film-forming composition according to the present invention can form a protective film that exhibits high chemical resistance, good optical parameters, and a desirable dry etching selectivity in the lithography process of semiconductor manufacturing.
Claims
1. (A) A compound having no repeating structural units, Contains a terminal group (A1), a polyvalent group (A2), and a linking group (A3), The terminal group (A1) is bonded only to the linking group (A3), The polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded on one side to the terminal group (A1) and on the other side to the polyvalent group (A2) and optionally to another linking group (A3); The terminal group (A1) is any one of the structures represented by the following formula (I): 【Chemistry 1】 In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. The polyvalent group (A2) is -O-, aliphatic hydrocarbon groups, A combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group having less than 10 carbon atoms, and A combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O- is a divalent to tetravalent group selected from the group consisting of The linking group (A3) represents an aromatic hydrocarbon group. compound, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent, Including, When the curing agent (B-2) is a phenol-based curing agent, bisphenol A, bisphenol F, 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl ether, 1,4-bis(4-hydroxyphenoxy)benzene, 1,3-bis(4-hydroxyphenoxy)benzene, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, poly-p-hydroxystyrene, hydroquinone, resorcinol, catechol, t-butylcatechol , t-butylhydroquinone, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1, selected from the group consisting of 8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated products or polyallylated products of the above dihydroxynaphthalenes, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak and allylated pyrogallol, A composition for forming a protective film against a wet etching solution for semiconductors.
2. The protective film-forming composition according to claim 1 , wherein the compound (A) is a compound represented by the following formula (II): 【Chemistry 2】 [In formula (II), Z １ , Z ２ are each independently 【Chemistry 3】 [In formula (I), * represents Y １ , or Y ２ The binding site is shown. X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. represents one of the following: Y １ , Y ２ each independently represents an aromatic hydrocarbon group, X １ , X ２ Each independently represents -Y １ -Z １ Or -Y ２ -Z ２ represents n1 and n2 each independently represent an integer of 0 to 4, provided that either one is 1 or more; m1 and m2 each independently represent 0 or 1; Q represents a divalent to tetravalent group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-.]
3. The compound (A) is represented by the following formula (III): 【Chemistry 4】 [In formula (III), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring; X represents an ether bond, an ester bond, or a nitrogen atom; n=1 when X is an ether bond or an ester bond, and n=2 when X is a nitrogen atom.] The protective film-forming composition according to claim 1 , comprising a partial structure represented by the following formula:
4. The protective film-forming composition according to claim 1 , wherein the compound (A) has a weight average molecular weight of 300 or more and 1,500 or less.
5. The protective film-forming composition according to claim 1 , which does not contain a novolak resin.
6. The protective film-forming composition according to any one of claims 1 to 5, wherein each of the compound (A), component (B), and solvent (C) does not contain a material containing one or more aromatic groups containing two or more substituents including hydroxy, thiol, and / or amine moieties.
7. The protective film-forming composition according to claim 1 , wherein the compound (A) has two or more of the linking groups (A3).
8. The protective film-forming composition according to any one of claims 1 to 7, wherein the component (B) includes a curing agent (B-2) selected from the group consisting of phenol-based curing agents, amide-based curing agents, amine-based curing agents, imidazoles, acid anhydride-based curing agents, and organic phosphines.
9. The protective film-forming composition according to claim 1 , further comprising (D) a compound having one phenolic hydroxy group, or a polymer having a unit structure having one phenolic hydroxy group.
10. A protective film, which is a fired product of a coating film comprising the protective film-forming composition according to any one of claims 1 to 9.
11. (A) A compound having no repeating structural units, Contains a terminal group (A1), a polyvalent group (A2), and a linking group (A3), The terminal group (A1) is bonded only to the linking group (A3), The polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded on one side to the terminal group (A1) and on the other side to the polyvalent group (A2) and optionally to another linking group (A3); The terminal group (A1) is any one of the structures represented by the following formula (I): 【Chemistry 5】 In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. The polyvalent group (A2) is -O-, aliphatic hydrocarbon groups, A combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group having less than 10 carbon atoms, and A combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O- is a divalent to tetravalent group selected from the group consisting of The linking group (A3) represents an aromatic hydrocarbon group. compound, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent, Including, When the curing agent (B-2) is a phenol-based curing agent, the curing agent may be selected from the group consisting of bisphenol F, 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl ether, 1,4-bis(4-hydroxyphenoxy)benzene, 1,3-bis(4-hydroxyphenoxy)benzene, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, hydroquinone, resorcinol, catechol, t-butylcatechol, t-butylhydroquinone, and the like. aryl, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated products or polyallylated products of the above dihydroxynaphthalenes, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak and allylated pyrogallol; The resist underlayer film forming composition, wherein the compound (A) is a compound represented by the following formula (II): 【Chemistry 6】 [In formula (II), Z 1 and Z 2 are each independently 【Chemistry 7】 In formula (I), * indicates a bonding site with Y 1 or Y 2 . X represents an ether bond or an ester bond, and n=1. represents one of the following: Y 1 and Y 2 each independently represent an aromatic hydrocarbon group; X 1 and X 2 each independently represent -Y 1 -Z 1 or -Y 2 -Z 2 ; n1 and n2 each independently represent an integer of 0 to 4, provided that either one is 1 or more; m1 and m2 each independently represent 0 or 1; Q represents a divalent to tetravalent group selected from the group consisting of -O-, an aliphatic hydrocarbon group, a combination of an aromatic hydrocarbon group having less than 10 carbon atoms and an aliphatic hydrocarbon group, and a combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O-.]
12. The compound (A) has the following formula (III): 【Chemistry 8】 [In formula (III), Ar represents a benzene ring, a naphthalene ring, or an anthracene ring; X represents an ether bond, an ester bond, or a nitrogen atom; n=1 when X is an ether bond or an ester bond, and n=2 when X is a nitrogen atom.] The resist underlayer film forming composition according to claim 11 , comprising a partial structure represented by the following formula:
13. The resist underlayer film forming composition according to claim 11 or 12, wherein the compound (A) has a weight average molecular weight of 300 or more and 1,500 or less.
14. A resist underlayer film forming composition according to any one of claims 11 to 13, which does not contain a novolak resin.
15. A resist underlayer film forming composition described in any one of claims 11 to 14, wherein each of the compound (A), component (B), and solvent (C) does not contain a material containing one or more aromatic groups containing two or more substituents including hydroxyl, thiol and / or amine moieties.
16. The resist underlayer film forming composition according to claim 11, wherein the compound (A) has two or more linking groups (A3).
17. The resist underlayer film forming composition according to any one of claims 11 to 16, wherein the component (B) includes a curing agent (B-2) selected from the group consisting of a phenol-based curing agent, an amide-based curing agent, an amine-based curing agent, an imidazole, an acid anhydride-based curing agent, and an organic phosphine.
18. A resist underlayer film forming composition described in any one of claims 11 to 17, further comprising (D) a compound having one phenolic hydroxy group, or a polymer having a unit structure having one phenolic hydroxy group.
19. A resist underlayer film, which is a fired product of a coating film comprising the resist underlayer film forming composition according to any one of claims 11 to 18.
20. (A) A compound having no repeating structural units, Contains a terminal group (A1), a polyvalent group (A2), and a linking group (A3), The terminal group (A1) is bonded only to the linking group (A3), The polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded on one side to the terminal group (A1) and on the other side to the polyvalent group (A2) and optionally to another linking group (A3); The terminal group (A1) is any one of the structures represented by the following formula (I): 【Chemistry 9】 In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. The polyvalent group (A2) is -O-, aliphatic hydrocarbon groups, A combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group having less than 10 carbon atoms, and A combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O- is a divalent to tetravalent group selected from the group consisting of The linking group (A3) represents an aromatic hydrocarbon group. compound, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent, Including, A method for producing a substrate with a protective film, which is used in the production of semiconductors, includes a step of applying a protective film-forming composition for a semiconductor wet etching solution onto a semiconductor substrate having a step and baking the composition to form a protective film.
21. (A) A compound having no repeating structural units, Contains a terminal group (A1), a polyvalent group (A2), and a linking group (A3), The terminal group (A1) is bonded only to the linking group (A3), The polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded on one side to the terminal group (A1) and on the other side to the polyvalent group (A2) and optionally to another linking group (A3); The terminal group (A1) is any one of the structures represented by the following formula (I): 【Chemistry 10】 In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. The polyvalent group (A2) is -O-, aliphatic hydrocarbon groups, A combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group having less than 10 carbon atoms, and A combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O- is a divalent to tetravalent group selected from the group consisting of The linking group (A3) represents an aromatic hydrocarbon group. compound, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent, Including, A method for producing a substrate with a resist pattern, which is used in the production of semiconductors, includes the steps of applying a protective film-forming composition for a semiconductor wet etching solution or a resist underlayer film-forming composition onto a semiconductor substrate and baking the composition to form a protective film as a resist underlayer film, forming a resist film on the protective film, and then exposing and developing the resist film to form a resist pattern.
22. On a semiconductor substrate on whose surface an inorganic film may be formed, (A) A compound having no repeating structural units, Contains a terminal group (A1), a polyvalent group (A2), and a linking group (A3), The terminal group (A1) is bonded only to the linking group (A3), The polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded on one side to the terminal group (A1) and on the other side to the polyvalent group (A2) and optionally to another linking group (A3); The terminal group (A1) is any one of the structures represented by the following formula (I): 【Chemistry 11】 In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. The polyvalent group (A2) is -O-, aliphatic hydrocarbon groups, A combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group having less than 10 carbon atoms, and A combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O- is a divalent to tetravalent group selected from the group consisting of The linking group (A3) represents an aromatic hydrocarbon group. compound, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent, Including, A method for manufacturing a semiconductor device, comprising the steps of forming a protective film using a protective film-forming composition for a semiconductor wet etching solution, forming a resist pattern on the protective film, dry etching the protective film using the resist pattern as a mask to expose a surface of the inorganic film or the semiconductor substrate, and wet etching and cleaning the inorganic film or the semiconductor substrate using the protective film after dry etching as a mask.
23. On a semiconductor substrate on whose surface an inorganic film may be formed, (A) A compound having no repeating structural units, Contains a terminal group (A1), a polyvalent group (A2), and a linking group (A3), The terminal group (A1) is bonded only to the linking group (A3), The polyvalent group (A2) is bonded only to the linking group (A3), the linking group (A3) is bonded on one side to the terminal group (A1) and on the other side to the polyvalent group (A2) and optionally to another linking group (A3); The terminal group (A1) is any one of the structures represented by the following formula (I): 【Chemistry 12】 In formula (I), * indicates a bonding site with the linking group (A3). X represents an ether bond, an ester bond, or a nitrogen atom, and when X is an ether bond or an ester bond, n=1, and when X is a nitrogen atom, n=2. The polyvalent group (A2) is -O-, aliphatic hydrocarbon groups, A combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group having less than 10 carbon atoms, and A combination of an aromatic hydrocarbon group having 10 or more carbon atoms and -O- is a divalent to tetravalent group selected from the group consisting of The linking group (A3) represents an aromatic hydrocarbon group. compound, (B) a thermal acid generator (B-1) and / or a curing agent (B-2), and (C) a solvent, forming a resist underlayer film using a resist underlayer film forming composition comprising the compound, forming a resist pattern on the resist underlayer film, dry etching the resist underlayer film using the resist pattern as a mask to expose a surface of the inorganic film or the semiconductor substrate, and etching the inorganic film or the semiconductor substrate using the resist underlayer film after dry etching as a mask.