Step substrate coating film formation composition containing plasma curable compound by unsaturated bond between carbon atoms

Abstract

To provide a plasma curable step substrate coating film formation composition which enables formation of a film having pattern filling property and flatness.SOLUTION: A plasma curable step substrate coating film formation composition contains a compound (E) containing at least one partial structure selected from a specific partial structure having a double bond or a triple bond derived from an unsaturated bond between carbon atoms, and a solvent (F). A crosslinked structure between unsaturated bonds by radical species is formed by irradiation of an unsaturated bond between carbon atoms with plasma. A substrate coating film formation composition does not contain a crosslinking agent and an acid catalyst, and a step substrate coating film (flattened film) formed by coating a step substrate coating film composition can be crosslinked by reaction of double bonds and triple bonds derived from an unsaturated bond between carbon atoms.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a coating film-forming composition for forming a planarized film on a substrate having steps by plasma exposure, and a method for producing a planarized laminated substrate using the coating film-forming composition for forming a planarized substrate. [Background technology]

[0002] In recent years, semiconductor integrated circuit devices have been fabricated to meet increasingly fine design rules, and in order to form finer resist patterns using photolithography technology, it is necessary to shorten the exposure wavelength. However, as the exposure wavelength becomes shorter, the depth of focus decreases, making it necessary to improve the planarization of the film formed on the substrate. In order to manufacture semiconductor devices with fine design rules, flattening technology on the substrate is becoming increasingly important.

[0003] As a method for forming a flattening film, for example, a method for forming a resist underlayer film by photocuring, which is formed under a resist, has been disclosed. A resist underlayer film-forming composition containing a polymer having an epoxy group or an oxetane group in a side chain and a photocationic polymerization initiator, or a resist underlayer film-forming composition containing a polymer having a radically polymerizable ethylenically unsaturated bond and a photoradical polymerization initiator has been disclosed (see Patent Document 1). Also disclosed is a resist underlayer film-forming composition that contains a silicon-based compound having a cationic polymerizable reactive group such as an epoxy group or a vinyl group, a photocationic polymerization initiator, and a photoradical polymerization initiator (see Patent Document 2). Also disclosed is a method for manufacturing a semiconductor device using a resist underlayer film containing a polymer having a crosslinkable functional group (such as a hydroxyl group) in the side chain, a crosslinking agent, and a photoacid generator (see Patent Document 3). In addition, although they are not photocrosslinkable resist underlayer films, resist underlayer films having unsaturated bonds in the main chain or side chain have been disclosed (see Patent Documents 4 and 5). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication Pamphlet 2006 / 115044 [Patent Document 2] International Publication Pamphlet 2007 / 066597 [Patent Document 3] International Publication Pamphlet 2008 / 047638 [Patent Document 4] International Publication Pamphlet 2009 / 008446 [Patent Document 5] Special table 2004-533637 Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional photocrosslinking materials, a resist underlayer film-forming composition containing a polymer having a thermal crosslinking functional group such as a hydroxyl group, a crosslinking agent, and an acid catalyst (acid generator) fills a pattern (e.g., a hole or trench structure) formed on a substrate, and when heated, a crosslinking reaction proceeds, causing an increase in viscosity, which makes filling into the pattern a problem. In addition, thermal shrinkage due to degassing occurs, which makes planarization a problem. In addition, in the case of a resist underlayer film-forming composition containing a polymer having a cationic polymerizable reactive group such as an epoxy group or a vinyl group and an acid generator, light irradiation and heating are performed, and in this case, thermal shrinkage due to degassing also occurs, which causes a problem in planarization.

[0006] An object of the present invention is to provide a plasma-curable composition for forming a coating film on an uneven substrate, which has high pattern filling properties and planarizing properties that enable the formation of a coating film on a substrate without causing degassing or thermal shrinkage. [Means for solving the problem]

[0007] As a first aspect, the present invention provides a partial structure (I) represented by the following formulae (1-1) to (1-7): [ka] (In the formula, R 1 , R 1a , R 3 , R 5a , and R 6a each independently represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms (the alkylene group and the arylene group may be optionally substituted with one or more amide groups or amino groups), an oxygen atom, a carbonyl group, a sulfur atom, -C(O)-NR a -, -NR b - or a divalent group consisting of a combination thereof; R 5 each independently represents a nitrogen atom, or a nitrogen atom and an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms (the alkylene group and the arylene group may be optionally substituted with one or more amido groups or amino groups), an oxygen atom, a carbonyl group, a sulfur atom, -C(O)-NR a - and -NR b - represents a trivalent group consisting of a combination of at least one group selected from the group consisting of 2 , R 2a , R 4 , and R 6 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a hydrogen atom and an alkylene group having 1 to 10 carbon atoms, an oxygen atom, a carbonyl group, or -C(O)-NR a - and -NR b - represents a monovalent group consisting of a combination of at least one group selected from the group consisting of a represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R b represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkylcarbonyl group having 1 to 10 carbon atoms, n represents the number of repeating units from 1 to 10, and a dotted line represents a chemical bond with an adjacent atom; As a second viewpoint, the above R 5a , and R 6a are alkylenes having 1 to 10 carbon atoms. a divalent group consisting of a group, an arylene group having 6 to 40 carbon atoms, an oxygen atom, a carbonyl group, a sulfur atom, or a combination thereof; As a third aspect, the plasma-curable composition for forming a coating film on a stepped substrate according to the first or second aspect, wherein the compound (E) is a compound (1) obtained by a reaction between a proton-generating compound (A) containing an unsaturated bond between carbon atoms and an epoxy compound (B), a compound (2) obtained by a reaction between an epoxy compound (C) containing an unsaturated bond between carbon atoms and a proton-generating compound (D), or a compound (3) obtained by a reaction between a compound having a hydroxy group produced by a reaction between the epoxy compound (B) or the epoxy compound (C) containing an unsaturated bond between carbon atoms and the proton-generating compound (A) containing an unsaturated bond between carbon atoms or the proton-generating compound (D), and a compound (G) capable of reacting with the hydroxy group containing an unsaturated bond. As a fourth aspect, the plasma-curable composition for forming a coating film for uneven substrates according to the third aspect, wherein the compound (E) is a reaction product of the proton-generating compound (A) and the epoxy compound (B) in a molar ratio of the protons of the proton-generating compound (A) to the epoxy groups of the epoxy compound (B) of 1:1 to 1:1.5; As a fifth aspect, the plasma-curable composition for forming a coating film for uneven substrates according to the third aspect, wherein the compound (E) is a reaction product of the epoxy compound (C) and the proton-generating compound (D) in a molar ratio of the epoxy group of the epoxy compound (C) to the proton of the proton-generating compound (D) of 1:1 to 1.5:1; As a sixth aspect, the plasma-curable composition for forming a coating film on a stepped substrate according to the third or fourth aspect, wherein the proton-generating compound (A) containing an unsaturated bond between carbon atoms is a carboxylic acid containing an unsaturated bond between carbon atoms, an acid anhydride containing an unsaturated bond between carbon atoms, an amine containing an unsaturated bond between carbon atoms, an amide containing an unsaturated bond between carbon atoms, an isocyanurate containing an unsaturated bond between carbon atoms, a phenol containing an unsaturated bond between carbon atoms, or a thiol containing an unsaturated bond between carbon atoms; As a seventh aspect, the plasma-curable composition for forming a coating film on a stepped substrate according to the third or fourth aspect, wherein the epoxy compound (B) is a glycidyl group-containing ether, a reaction product of a phenolic hydroxy group-containing compound and epichlorohydrin, a reaction product of a phenolic hydroxy group-containing resin and epichlorohydrin, a glycidyl group-containing isocyanurate, an epoxycyclohexyl group-containing compound, an epoxy group-substituted cyclohexyl compound, or a glycidyl ester compound; As an eighth aspect, the plasma-curable composition for forming a coating film on an uneven substrate according to the third aspect or the fifth aspect, wherein the epoxy compound (C) containing an unsaturated bond between carbon atoms is a glycidyl ester compound containing an unsaturated bond between carbon atoms, a reaction product of a compound containing a phenolic hydroxy group containing a carbon atom unsaturated bond and epichlorohydrin, or a reaction product of a resin containing a phenolic hydroxy group containing a carbon atom unsaturated bond and epichlorohydrin; As a ninth aspect, the plasma-curable composition for forming a coating film on a stepped substrate according to the third or fifth aspect, in which the proton-generating compound (D) is a phenolic hydroxy group-containing compound, a carboxylic acid-containing compound, an amine-containing compound, a thiol-containing compound, or an imide-containing compound; As a tenth aspect, the plasma-curable composition for forming a coating film on an uneven substrate according to the third aspect or the fifth aspect, in which the compound (G) is an acid halide, an acid anhydride, an isocyanate, or an alkyl halide containing an unsaturated bond between a carbon atom and a carbon atom, or the compound (A); As an eleventh aspect, the plasma-curable composition for forming a coating film for uneven substrates according to any one of the first to tenth aspects, wherein the plasma is produced by irradiation with a plasma gas used as an etching gas. As a twelfth aspect, the plasma-curable composition for forming a coating film for uneven substrates according to any one of the first to tenth aspects, in which the plasma is a halogen-containing gas plasma, an oxygen gas plasma, or a hydrogen gas plasma. As a thirteenth aspect, the step substrate covering composition according to any one of the first to twelfth aspects is a resist underlayer film forming composition used in a lithography process for manufacturing a semiconductor device. The plasma-curable coating film-forming composition for uneven substrates according to the present invention, As a fourteenth aspect, a method for producing a coated substrate, the method comprising: a step (i) of applying the plasma-curable uneven substrate coating film-forming composition according to any one of the first to thirteenth aspects to a substrate having a step; and a step (ii) of irradiating the substrate having a step with plasma. As a fifteenth aspect, a method for producing a coated substrate according to the fourteenth aspect, further comprising a step (ia) of heating the plasma-curable step-difference substrate coating film-forming composition at a temperature of 70 to 400° C. for 10 seconds to 5 minutes after applying the composition in the step (i); As a sixteenth aspect, the method for producing a coated substrate according to the fourteenth or fifteenth aspect, in which the plasma irradiation in the step (ii) is plasma irradiation with a fluorine-containing gas or a mixed gas of oxygen and an inert gas; As a seventeenth aspect, the method for producing a coated substrate according to any one of the fourteenth to fifteenth aspects, in which the plasma irradiation in the step (ii) is performed with an etching gas using an apparatus used in a dry etching step; As an eighteenth aspect, the method for producing a coated substrate according to any one of the fourteenth to seventeenth aspects, in which the substrate has an open area (non-pattern area) and a pattern area of ​​DENCE (dense) and ISO (sparse), and the aspect ratio of the pattern is 0.1 to 10. As a 19th aspect, the method for producing a coated substrate according to any one of the 18th aspects, in which a bias (a coating step) between the open area and the pattern area is 1 to 50 nm; As a twentieth aspect, a method for producing a semiconductor device, comprising the steps of forming an underlayer film on a substrate having a step from the uneven substrate coating film-forming composition according to any one of the first to thirteenth aspects, forming a resist film on the underlayer film, irradiating the resist film with light or an electron beam and developing the resist film to form a resist pattern, etching the underlayer film using the resist pattern, and processing a semiconductor substrate using the patterned underlayer film; As a twenty-first aspect, the method for producing a semiconductor device according to the twentieth aspect, wherein the substrate having the step is the substrate according to the eighteenth aspect; As a twenty-second aspect, the method for producing a semiconductor device according to the twentieth aspect, in which the step of forming an underlayer film from the step substrate coating film-forming composition is performed by the method according to any one of the fourteenth to nineteenth aspects; As a twenty-third aspect, there is provided a method for producing a semiconductor device according to the twentieth aspect, in which an underlayer film obtained from the uneven substrate coating film-forming composition has a coating step according to the nineteenth aspect; As a 24th aspect, a method for producing a semiconductor device, the method comprising the steps of: forming an underlayer film on a substrate having a step from the plasma-curable uneven substrate coating film-forming composition according to any one of the first to 13th aspects; forming a hard mask on the underlayer film; further forming a resist film on the hard mask; forming a resist pattern on the resist film by irradiating the resist film with light or an electron beam and developing the resist film; etching the hard mask with the resist pattern; etching the underlayer film with the patterned hard mask; and processing a semiconductor substrate with the patterned underlayer film; As a 25th aspect, the method for manufacturing a semiconductor device according to the 24th aspect, wherein the substrate having the step is the substrate according to the 18th aspect; As a 26th aspect, the method for producing a semiconductor device according to the 24th aspect, in which the step of forming an underlayer film from the step substrate coating film-forming composition is performed by the method according to any one of the 14th aspect to the 19th aspect; and According to a twenty-seventh aspect, there is provided a method for producing a semiconductor device according to the twenty-fourth aspect, wherein an underlayer film obtained from the composition for forming a coating film for an uneven substrate has a coating step according to the nineteenth aspect. Effect of the Invention

[0008] The coating film-forming composition for uneven substrates of the present invention is applied onto a substrate, and in some cases is filled into a pattern by further reflowing due to heating. During this process, the viscosity of the coating film-forming composition for uneven substrates does not increase because it does not have a thermal crosslinking site or an acid catalyst, and a flat film is formed regardless of whether the substrate has an open area (non-pattern area) or a DENCE (dense) or ISO (sparse) pattern area. The plasma irradiation of the unsaturated bonds between carbon atoms forms a crosslinked structure between the unsaturated bonds by radical species. The coating film forming composition for uneven substrates of the present invention does not contain a crosslinking agent or an acid catalyst, and the coating film for uneven substrates (flattening film) formed by applying the coating film forming composition for uneven substrates can be crosslinked by a reaction between double bonds and triple bonds derived from the unsaturated bonds between carbon atoms.

[0009] The coating film (flattening film) formed from the coating film-forming composition for uneven substrates of the present invention does not undergo a crosslinking reaction between the crosslinking agent and the acid catalyst during thermal reflow, and the crosslinking by subsequent plasma irradiation is a plasma reaction that does not involve degassing, so that the coating film for uneven substrates does not undergo thermal shrinkage. As a result, the present invention can provide a coating film-forming composition for uneven substrates that simultaneously satisfies the filling properties into a pattern and the flattening properties after filling, making it possible to form an excellent flattening film. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention relates to a plasma-curable composition for forming a coating film for uneven substrates, which comprises a compound (E) containing at least one partial structure selected from partial structures (I) and a solvent (F).

[0011] The plasma is generated by irradiation of a plasma gas used as an etching gas for etching the resist pattern. As the plasma, a halogen-containing gas plasma, an oxygen gas plasma, or a hydrogen gas plasma can be used alone. As the plasma, a mixed gas plasma in which a gas selected from a halogen-containing gas, oxygen, and hydrogen is mixed, or a mixed gas plasma in which the above gases are further mixed with other gases can be used.

[0012] Examples of halogens include fluorine and chlorine. For example, examples of halogen-containing gases include tetrafluoromethane (CF), perfluorocyclobutane (C4F8), perfluoropropane (C3F8), trifluoromethane (CHF3), difluoromethane (CH2F2), nitrogen trifluoride, sulfur hexafluoride, chlorine trifluoride, chlorine, trichloroborane, and dichloroborane. Other gases include inert gases, carbon monoxide, etc. Inert gases include, for example, nitrogen gas, helium gas, and argon gas. As the plasma gas, tetrafluoromethane (CF4) plasma and mixed gas plasma of oxygen and nitrogen can be preferably used.

[0013] The partial structure (I) is at least one partial structure selected from the above formulae (1-1) to (1-7). Examples of the partial structure (I) include a partial structure of the formula (1-1), a partial structure of the formula (1-2), a partial structure of the formula (1-3), a partial structure of the formula (1-4), a partial structure of the formula (1-5), a combination of the partial structure of the formula (1-6) and the partial structure of the formula (1-7), a combination of the partial structure of the formula (1-1) and the partial structure of the formula (1-3), or a combination of the partial structure of the formula (1-1) and the partial structure of the formula (1-4).

[0014] In the above formula, R 1 , R 1a , R 3 , R 5a , and R 6a each independently represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms (the alkylene group and the arylene group may be optionally substituted with one or more amide groups or amino groups), an oxygen atom, a carbonyl group, a sulfur atom, -C(O)-NR a -, -NR b - or a divalent group consisting of a combination thereof; R 5each independently represents a nitrogen atom, or a nitrogen atom and an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms (the alkylene group and the arylene group may be optionally substituted with one or more amido groups or amino groups), an oxygen atom, a carbonyl group, a sulfur atom, -C(O)-NR a - and -N R b - represents a trivalent group consisting of a combination of at least one group selected from the group consisting of 2 , R 2a , R 4 , and R 6 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a hydrogen atom and an alkylene group having 1 to 10 carbon atoms, an oxygen atom, a carbonyl group, or -C(O)-NR a - and -NR b - represents a monovalent group consisting of a combination of at least one group selected from the group consisting of a represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, R b represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkylcarbonyl group having 1 to 10 carbon atoms, n represents the number of repeating units from 1 to 10, and The dotted lines represent chemical bonds to adjacent atoms.

[0015] Above R 5a , and R 6a can each be an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms, an oxygen atom, a carbonyl group, a sulfur atom, or a divalent group consisting of a combination thereof.

[0016] The above-mentioned coating film forming composition for uneven substrates may contain additives such as a surfactant, if necessary.

[0017] The solid content of this composition is 0.1 to 70 mass%, or 0.1 to 60 mass%, or 0.2 to 30 mass%, or 0.3 to 15 mass%. The solid content is the content of all components excluding the solvent from the composition for forming a coating film for uneven substrates. The compound (E) can be contained in the solid content in a ratio of 1 to 100 mass%, or 1 to 99.9 mass%, or 50 to 99.9 mass%, or 50 to 95 mass%, or 50 to 90 mass%.

[0018] The compound (E) used in the present invention has an average molecular weight of 600 to 1,000,000, or 600 to 200,000, or 1,500 to 15,000.

[0019] Compound (E) can form a crosslinked structure by a plasma reaction of an intermolecular or intramolecular unsaturated bond between carbon atoms, and can have at least one unsaturated bond between carbon atoms, i.e., an unsaturated double bond between carbon atoms, in the molecule, and can also have a plurality of such unsaturated bonds (e.g., 1 to 1,000) in the molecule.

[0020] The alkyl group includes alkyl groups having 1 to 10 carbon atoms, such as 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, a 1-ethyl-n-propyl group, a cyclopentyl group, a 1-methyl-cyclobutyl group, a 2-methyl-cyclobutyl group, a 3-methyl-cyclobutyl group, a 1,2-dimethyl-cyclopropyl group, a 2,3-dimethyl-cyclopropyl group, a 1-ethyl-cyclopropyl group, a 2-ethyl-cyclopropyl group, an n-hexyl group, a 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, 1-ethyl-1-methyl-n-propyl, 1-ethyl-2-methyl-n-propyl, cyclohexyl, 1-methyl-cyclopentyl, 2-methyl-cyclopentyl, 3-methyl-cyclopentyl, 1-ethyl-cyclobutyl, 2-ethyl-cyclobutyl, 3-ethyl-cyclobutyl, 1,2-dimethyl-cyclobutyl, 1,3-dimethyl-cyclobutyl, 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, 2,2,3-trimethyl-cyclopropyl group, 1-ethyl-2-methyl-cyclopropyl group, 2-ethyl-1-methyl-cyclopropyl group, 2-ethyl-2-methyl-cyclopropyl group and 2-ethyl-3-methyl-cyclopropyl group.

[0021] The aryl group is an aryl group having 6 to 40 carbon atoms, and examples thereof include a phenyl group, a biphenyl group, a terphenylene group, a fluorene group, a naphthyl group, an anthryl group, a pyrene group, and a carbazole group.

[0022] The alkylene group is exemplified by a divalent organic group derived from the alkyl group. The arylene group is exemplified by a divalent organic group derived from the aryl group. The alkylcarbonyl group is exemplified by a group in which the alkyl group is bonded to a carbonyl group.

[0023] In the formula (1-4) of the partial structure (I), R 5a , and R 6a may each independently be an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms, an oxygen atom, a carbonyl group, a sulfur atom, or a divalent group consisting of a combination thereof.

[0024] In the partial structure (I), the partial structure represented by formula (1-4) is bonded to the partial structure represented by formula (II) to form a chain polymer. 5a , and R 6a When the group is composed of these groups, the ability to form a crosslinked structure by plasma reaction is enhanced, which is preferable.

[0025] The compound (E) can have a partial structure (I) and a partial structure (II). The partial structure (II) is a partial structure represented by the following formula (2-1) or formula (2-2), and is a partial structure having a hydroxy group. [ka] In formula (2-1) and formula (2-2), R 7 , R 8 , R 9 , R 10 and R 11 each represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a dotted line represents a chemical bond to an adjacent atom.

[0026] Compound (E) may be compound (1) obtained by the reaction of a proton-generating compound (A) containing an unsaturated bond between carbon atoms with an epoxy compound (B); compound (2) obtained by the reaction of an epoxy compound (C) containing an unsaturated bond between carbon atoms with a proton-generating compound (D); or compound (3) obtained by the reaction of a compound having a hydroxy group produced by the reaction of an epoxy compound (B) or an epoxy compound (C) containing an unsaturated bond between carbon atoms with a proton-generating compound (A) containing an unsaturated bond between carbon atoms or a proton-generating compound (D), with a compound (G) capable of reacting with the hydroxy group containing an unsaturated bond.

[0027] The partial structure (II) contains a hydroxyl group generated by the reaction of an epoxy group with a proton-generating compound, and the compound (E) can contain an epoxy group and a hydroxyl group in a molar ratio of 0≦(epoxy group) / (hydroxyl group)≦0.5. The epoxy compound (B) or (C) is reacted with the proton-generating compound (A) or (D) to cause an addition reaction with the epoxy group to generate a hydroxyl group. The ratio of the addition reaction is a molar ratio of 0≦(epoxy group) / (hydroxyl group)≦0.5, but it is preferable that the amount of residual epoxy groups is small, and it is desirable that the ratio of residual epoxy groups in the compound (E) is zero or close to zero in terms of photoreactivity.

[0028] The compound (E) can be obtained by reacting the proton-generating compound (A), protons, and the epoxy compound (B) in a molar ratio of the protons of the proton-generating compound (A) to the epoxy groups of the epoxy compound (B) of 1:1 to 1:1.5. The compound (E) can be obtained by reacting the epoxy compound (C) with the proton-generating compound (D) in a molar ratio of the epoxy group of the epoxy compound (C) to the proton of the proton-generating compound (D) of 1:1 to 1.5:1.

[0029] The proton generating group of the proton generating compound (A) reacts with the epoxy group of the epoxy compound (B) to form the partial structure (I) and the partial structure (II). R 1 , R 3 , R 5 , R 5a , R 6a , R 1a and the oxygen atom of the ester group is R 7 and R 10 or R 9 and R 11 or a carbon atom in the ring of the hydroxycyclohexyl ring.

[0030] Examples of the proton-generating compound (A) containing an unsaturated bond between carbon atoms include a carboxylic acid containing an unsaturated bond between carbon atoms, an acid anhydride containing an unsaturated bond between carbon atoms, an amine containing an unsaturated bond between carbon atoms, an amide containing an unsaturated bond between carbon atoms, an isocyanurate containing an unsaturated bond between carbon atoms, a phenol containing an unsaturated bond between carbon atoms, and a thiol containing an unsaturated bond between carbon atoms.

[0031] Examples of the epoxy compound (B) include a glycidyl group-containing ether, a reaction product of a phenolic hydroxy group-containing compound with epichlorohydrin, a reaction product of a phenolic hydroxy group-containing resin with epichlorohydrin, a glycidyl group-containing isocyanurate, an epoxycyclohexyl group-containing compound, an epoxy group-substituted cyclohexyl compound, or a glycidyl ester compound. The epoxy compound (B) is a compound that does not have an unsaturated bond and forms a crosslinked structure, for example, by plasma irradiation.

[0032] In addition, the epoxy group of compound (C) reacts with the proton generating group of compound (D) to form partial structure (I) and partial structure (II). R 1 , R 3 , R 5 , R 5a , R 6a , R 1a and the oxygen atom of the ester group is R 7 and R 10 , or R 9 and R 11 or a carbon atom in the ring of the hydroxycyclohexyl ring.

[0033] Examples of the epoxy compound (C) containing an unsaturated bond between carbon atoms include a glycidyl ester compound containing an unsaturated bond between carbon atoms, a reaction product of a phenolic hydroxy group-containing compound containing an unsaturated bond between carbon atoms and epichlorohydrin, and a reaction product of a phenolic hydroxy group-containing resin containing an unsaturated bond between carbon atoms and epichlorohydrin.

[0034] Examples of the proton generating compound (D) include a phenolic hydroxy group-containing compound, a carboxylic acid-containing compound, an amine-containing compound, a thiol-containing compound, or an imide-containing compound. Some examples include: The proton-generating compound (D) is, for example, a compound that does not have an unsaturated bond that forms a crosslinked structure upon plasma irradiation.

[0035] The molar ratio of the unsaturated bond group between carbon atoms based on partial structure (I) and the hydroxyl group based on partial structure (II) can be 0.01≦(partial structure (II)) / (partial structure (I)+partial structure (II))≦0.8. If the reaction between compound (A) and compound (B), or compound (C) and compound (D) occurs in a molar ratio of 1:1, the molar ratio of the unsaturated bond group between carbon atoms based on partial structure (I) and the hydroxyl group based on partial structure (II) is generated in a molar ratio of 1:1. However, when an arbitrary compound that does not have an unsaturated bond between carbon atoms is used as the compound having a proton generating group, the ratio of the generated hydroxyl group increases, but in the present invention, the molar ratio can be up to 1:4.

[0036] The compound (E) can contain the partial structure (I) and the partial structure (II) in a ratio of 1 to 1000. This includes everything from single molecular compounds to polymers, and each of them has a ratio within the above range.

[0037] Examples of the proton-generating compound (A) containing an unsaturated bond between carbon atoms used in the present invention include the following. [ka] [ka] [ka] The above compounds are available as reagents.

[0038] Examples of the epoxy compound (B) used in the present invention include the following. [ka] [ka] [ka] [ka] [ka] [ka] Formula (B-1) is available from DIC Corporation under the trade name EPICLON HP-5000. The compound represented by formula (B-2) is available from Nippon Kayaku Co., Ltd. under the trade name EPPN-501H. The compound represented by formula (B-3) is available from Asahi Kasei Epoxy Corporation under the trade name ECN-1229. The compound represented by formula (B-4) is available from Nippon Kayaku Co., Ltd. under the trade name EPPN-501H. The compound represented by formula (B-5) is available from Nippon Kayaku Co., Ltd. under the trade name NC-2000L. The compound represented by formula (B-6) is available from Nippon Kayaku Co., Ltd. under the trade name NC-3000L. The compound represented by formula (B-7) is available from Nippon Kayaku Co., Ltd. under the trade name NC-7000L. The compound represented by formula (B-8) is available from Nippon Kayaku Co., Ltd. under the trade name NC-7300L. The compound represented by formula (B-9) is available from Nippon Kayaku Co., Ltd. under the trade name NC-3500. The compound represented by formula (B-10) is available from DIC Corporation under the trade name HP-7200L. The compound represented by formula (B-11) is available from Daicel Corporation under the trade name EHPE-3150. The compound represented by formula (B-12) is available from DIC Corporation under the trade name EPICLON HP-4700. The compound represented by formula (B-13) is available from Asahi Yukizai Kogyo Co., Ltd. under the trade name TEP-G. Formula (B-14) is a product of Daicel Corporation, trade name Epolead GT401, and a, b, c and d are each 0 or 1, and a+b+c+d=1. The compound represented by formula (B-15) is available from Nissan Chemical Industries, Ltd. under the trade name TEPIC-SS. Compound (B-16) is available from Nagase Chemtec Corporation under the trade name EX-411. Compound (B-17) is available from Nagase Chemtec Corporation under the trade name EX-521. The compound represented by formula (B-18) is available from Nippon Steel & Sumikin Chemical Co., Ltd. under the trade name YH-434L. The compound represented by formula (B-19) is available from Nagase Chemtec Corporation under the trade name EX-711. The compound represented by formula (B-20) is available from DIC Corporation under the trade name YD-4032D. Compound (B-21) is available from DIC Corporation under the trade name HP-4770. The compound represented by formula (B-22) is available from Nippon Steel & Sumikin Chemical Co., Ltd. under the trade name YH-434L. Formula (B-23) is available as a reagent. Compound (B-24) is available from Nippon Kayaku Co., Ltd. under the trade name RE-810NM. Compound (B-25) is available from Nippon Kayaku Co., Ltd. under the trade name FAE-2500. Compound (B-26) is available from Nippon Kayaku Co., Ltd. under the trade name NC-6000. Furthermore, EPICLON HP-6000 (epoxy value 244 g / eq.), a product of DIC Corporation, can also be used.

[0039] Examples of the epoxy compound (C) containing an unsaturated bond between carbon atoms used in the present invention include the following. [ka] Formula (C-1) is available from Shikoku Chemical Industries Co., Ltd. under the trade name MA-DGIC. Formula (C-3) is available from Shikoku Chemical Industry Co., Ltd. under the trade name DA-MGIC. Other compounds are available as reagents.

[0040] Examples of the proton-generating compound (D) used in the present invention include the following. [ka] [ka] [ka] [ka] [ka] [ka] The above compounds are available as reagents. Formula (D-23) is available from Asahi Yukizai Co., Ltd. under the trade name TEP-DF. The compound represented by formula (D-24) is available from Asahi Yukizai Co., Ltd. under the trade name TEP-TPA. Formula (D-25) is available from Asahi Yukizai Co., Ltd. under the trade name TEPC-BIP-A. Formula (D-26) is available from Asahi Yukizai Co., Ltd. under the trade name TEP-BOCP. Formulae (D-27) to (D-37) are novolak resins made from raw materials that can be procured from reagents. The weight average molecular weight of the resulting polymer can be adjusted to the range of 1,000 to 100,000, 1,000 to 50,000, or 1,000 to 10,000.

[0041] In the present invention, the compound (E) has a hydroxyl group of partial structure (II), and some of the hydroxyl groups can be reacted with compound (G) that is capable of reacting with the hydroxyl group containing an unsaturated bond between carbon atoms. The reaction of compound (G) improves plasma reactivity. Even with this reaction, the molar ratio in compound (E) is in the range of 0.01≦(partial structure (II)) / (partial structure (I)+partial structure (II))≦0.8.

[0042] Examples of the compound (G) include an acid halide, an acid anhydride, an isocyanate, or an alkyl halide containing an unsaturated bond between carbon atoms, or the proton-generating compound (A) containing an unsaturated bond between carbon atoms.

[0043] Examples of the compound (G) include the following. [ka]

[0044] In the above formula, X represents a halogen atom such as fluorine, chlorine, bromine, or iodine. For example, X in formula (G-1) is preferably a chlorine atom, X in formula (G-2) is preferably a chlorine atom, X in formula (G-7) is preferably a bromine atom, and X in formula (G-8) is preferably a chlorine atom. The above compound is available as a reagent.

[0045] Examples of the compound (E) used in the present invention include the following. [ka] [ka] [ka] [ka] [ka] [ka] In the formula (E-17), the molar ratio of the unit structure (E-17-1) to the unit structure (E-17-2) is 60:40. [ka] [ka]

[0046] The step substrate coating film forming composition of the present invention may contain a surfactant. Examples of the surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether, polyoxyethylene alkylaryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether, polyoxyethylene-polyoxypropylene block copolymers, sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate ... nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters, such as polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; F-TOP (registered trademark) EF301, EF303, and EF352 (manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.); Megafac (registered trademark) F171, F173, R30, R-30N, and R-40L; Examples of the surfactant include fluorine-based surfactants such as Fluorad FC430 and FC431 (manufactured by Sumitomo 3M Co., Ltd.), Asahiguard (registered trademark) AG710, Surflon (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by Asahi Glass Co., Ltd.), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). One of these surfactants may be added, or two or more of them may be added in combination. The content of the surfactant is, for example, 0.01% to 5% by mass based on the solid content of the step substrate coating film forming composition of the present invention excluding the solvent described below.

[0047] In the present invention, the solvent for dissolving the compound (E) is ethylene glycol monomethyl ether. ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisopropyl ether, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monoethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol propyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol dimethyl ether, toluene, xylene, styrene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 1-octanol, ethylene glycol, hexylene glycol, trimethylene glycol, 1-methoxy-2-butanol, cyclohexanol, diacetone alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, propylene glycol, benzyl alcohol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, γ-butyrolactone, acetone, methyl isopropyl ketone, diethyl ketone, methyl isobutyl ketone, methyl normal butyl ketone, isopropyl acetate ketone, normal propyl acetate, isobutyl acetate, methanol, ethanol, isopropanol, tert-butanol, allyl alcohol, normal propanol, 2-methyl-2-butanol, isobutanol, normal butanol, 2-methyl-1-butanol, 1-pentanol, 2-methyl-1-pentanol, 2-ethylhexanol, 1- Octanol, ethylene glycol, hexylene glycol, trimethylene glycol, 1-methoxy-2-butanol, diacetone alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, propylene glycol, benzyl alcohol, isopropyl ether, 1,4-dioxane, N,N-dimethyltetramamide, N,N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, N-cyclohexyl-2-pyrrolidinone, etc. can be used. These organic solvents can be used alone or in combination of two or more.

[0048] Next, a method for forming a coating film (flattening film) on a stepped substrate using the coating film-forming composition of the present invention will be described. The coating film-forming composition for a stepped substrate is applied to a substrate (e.g., transparent substrate such as silicon / silicon dioxide coating, glass substrate, ITO substrate, etc.) used in the manufacture of precision integrated circuit elements by a suitable application method such as a spinner or coater, and then baked (heated) and irradiated with plasma to form a coating film. That is, the coated substrate is manufactured by including a step (i) of applying the coating film-forming composition for a stepped substrate to a substrate having steps, and a step (ii) of irradiating with plasma.

[0049] When applying using a spinner, the application can be performed, for example, at a rotation speed of 100 to 5000 for 10 to 180 seconds.

[0050] The above substrate has an open area (non-pattern area) and DENCE (dense) and ISO (sparse) pattern areas, and the aspect ratio of the pattern is 0.1 to 10. Non-patterned area refers to the area on the substrate where there are no patterns (e.g. holes or trench structures), DENCE (dense) refers to the area on the substrate where patterns are densely packed, and ISO (coarse) refers to the area on the substrate where patterns are densely packed. indicates an area on the substrate where the patterns are widely spaced and scattered. The aspect ratio of a pattern is the ratio of the pattern depth to the pattern width. The pattern depth is usually several hundred nm (e.g., about 100 to 300 nm), and DENCE (dense) is an area where patterns of several tens of nm (e.g., 30 to 80 nm) are densely packed at intervals of about 100 nm. ISO (coarse) is an area where patterns of several hundred nm (e.g., about 200 to 1000 nm) are scattered.

[0051] Here, the thickness of the uneven substrate coating film (flattening film) is preferably 0.01 to 3.0 μm. In step (ia), the coating may be heated at 70 to 400° C. or 100 to 250° C. for 10 seconds to 5 minutes or 30 seconds to 2 minutes. This heating causes the uneven substrate coating film forming composition to reflow, forming a flat uneven substrate coating film (flattening film).

[0052] In the step (ii), plasma irradiation using a fluorine-containing gas or a mixed gas of oxygen and an inert gas can be used. For the plasma irradiation in the step (ii), a method using an etching gas in an apparatus used in a dry etching step of a resist pattern can be used. This plasma exposure causes a plasma reaction, resulting in cross-linking and imparting solvent resistance to the coating film on the stepped substrate.

[0053] The stepped substrate coating film (flattening film) thus formed desirably has zero bias (coating step) between the open area and the pattern area, but can be flattened to within the range of 1 to 50 nm, or 1 to 25 nm. The bias between the open area and the DENCE area is about 15 to 20 nm, and the bias between the open area and the ISO area is about 1 to 10 nm.

[0054] The uneven substrate coating film (flattening film) obtained by the present invention can be coated with a resist film, and the resist film can be exposed and developed by lithography to form a resist pattern, and a substrate can be processed according to the resist pattern. In this case, the uneven substrate coating film (flattening film) is a resist underlayer film, and the uneven substrate coating film forming composition is also a resist underlayer film forming composition.

[0055] A good resist pattern can be obtained by applying a resist onto the stepped substrate coating film of the present invention, irradiating the resist with light or electron beams through a specified mask, developing, rinsing, and drying. If necessary, post-exposure baking (PEB) after irradiation with light or electron beams can also be performed. Then, the stepped substrate coating film in the portion where the resist has been developed and removed in the above process is removed by dry etching, and a desired pattern can be formed on the substrate.

[0056] The exposure light for the photoresist is actinic radiation such as near ultraviolet light, far ultraviolet light, or extreme ultraviolet light (e.g., EUV, wavelength 13.5 nm), and light with wavelengths of, for example, 248 nm (KrF laser light), 193 nm (ArF laser light), or 157 nm (F2 laser light) is used. For the light irradiation, any method can be used without particular limitation as long as it can generate acid from the photoacid generator in the resist, and the exposure dose is 1 to 3000 mJ / cm. 2 , or 10 to 3000 mJ / cm 2 , or 10 to 1000 mJ / cm 2 by. The electron beam resist can be irradiated with an electron beam using, for example, an electron beam irradiation device.

[0057] The developer for the resist having the uneven substrate coating film formed by using the uneven substrate coating film forming composition of the present invention is preferably sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, or the like. The aqueous solutions of alkalis such as inorganic alkalis such as sodium, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline, and cyclic amines such as pyrrole and piperidine can be used. Furthermore, the aqueous solutions of the above alkalis can be used by adding an appropriate amount of alcohols such as isopropyl alcohol and surfactants such as nonionic surfactants. Among these, the preferred developer is a quaternary ammonium salt, and more preferably tetramethylammonium hydroxide and choline.

[0058] The developer may be an organic solvent.For example, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether butyl acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, lactate Examples of the isopropyl ester include propyl acetate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, and propyl 3-methoxypropionate.Furthermore, a surfactant may be added to these developers. The development conditions are appropriately selected from a temperature of 5 to 50° C. and a time of 10 to 600 seconds.

[0059] In the present invention, a semiconductor device can be manufactured through a process of forming an uneven substrate coating film on a semiconductor substrate from a stepped substrate coating film forming composition, a process of forming a resist film thereon, a process of forming a resist pattern by irradiating with light or an electron beam and developing, a process of etching the uneven substrate coating film with the resist pattern, and a process of processing a semiconductor substrate with the patterned uneven substrate coating film.

[0060] In the future, as resist patterns become finer, problems such as resolution problems and the resist pattern collapsing after development will arise, so there is a demand for thinner resists. As a result, it is difficult to obtain a resist pattern film that is thick enough for substrate processing, and a process is required in which not only the resist pattern but also the stepped substrate coating film formed between the resist and the semiconductor substrate to be processed functions as a mask during substrate processing. Unlike conventional high etch rate resist underlayer films, there is an increasing demand for stepped substrate coating films having a dry etching rate selectivity close to that of resists, a stepped substrate coating film having a dry etching rate selectivity smaller than that of resists, and a stepped substrate coating film having a dry etching rate selectivity smaller than that of semiconductor substrates. In addition, such stepped substrate coating films can be provided with anti-reflection properties, and can also have the functions of conventional anti-reflection films.

[0061] On the other hand, in order to obtain a fine resist pattern, a process has begun to be used in which the resist pattern and the stepped substrate coating film are made narrower during dry etching of the stepped substrate coating film than the pattern width during resist development. As a stepped substrate coating film for such a process, unlike conventional high etch rate anti-reflective films, a stepped substrate coating film having a selectivity ratio of a dry etching rate close to that of the resist is required. In addition, such a stepped substrate coating film can be given anti-reflective properties, and can also have the functions of conventional anti-reflective films.

[0062] In the present invention, after the stepped substrate coating film of the present invention is formed on the substrate, a resist can be applied directly onto the stepped substrate coating film, or after one or several layers of a coating material are formed on the stepped substrate coating film as required. This narrows the resist pattern width, and even if the resist is thinly coated to prevent pattern collapse, the substrate can be processed by selecting an appropriate etching gas.

[0063] That is, a semiconductor device can be manufactured through the steps of forming a stepped substrate coating film on a semiconductor substrate using a stepped substrate coating film forming composition, forming thereon a hard mask using a coating material containing a silicon component or the like or a hard mask by vapor deposition (e.g., silicon oxynitride), forming a resist film on top of the hard mask, forming a resist pattern by exposure to light or an electron beam and developing, etching the hard mask using the resist pattern with a halogen-based gas, etching the stepped substrate coating film using the patterned hard mask with an oxygen-based gas or hydrogen-based gas, and processing the semiconductor substrate with a halogen-based gas using the patterned stepped substrate coating film.

[0064] Examples of halogens include fluorine and chlorine. For example, examples of halogen-containing gases include tetrafluoromethane (CF), perfluorocyclobutane (C4F8), perfluoropropane (C3F8), trifluoromethane (CHF3), difluoromethane (CH2F2), nitrogen trifluoride, sulfur hexafluoride, chlorine trifluoride, chlorine, trichloroborane, and dichloroborane. Other gases that can be mixed include inert gases, carbon monoxide, etc. Examples of inert gases include nitrogen gas, helium gas, and argon gas.

[0065] Compound (E) may have a light absorbing moiety in its skeleton. The light absorbing moiety is not particularly limited, but may be, for example, a benzyl group, a phenyl group, a naphthyl group, an anthracenyl group, a triazinyl group, a cyanuric group, a thiadiazolyl group, or a thiazolyl group. When considering the effect as an anti-reflection film, the composition for forming a coating film for uneven substrates of the present invention has light-absorbing moieties incorporated into the skeleton, so that no diffusion occurs into the photoresist during heating and drying, and the light-absorbing moieties have sufficiently large light-absorbing performance, so that the composition has a high anti-reflection effect.

[0066] The composition for forming a coating film for uneven substrates of the present invention has high thermal stability, can prevent contamination of the upper layer film by decomposition products during firing, and allows for a generous temperature margin in the firing step.

[0067] Furthermore, the step substrate coating of the present invention has a function of preventing light reflection depending on the process conditions. and further, it can be used as a film having the function of preventing interaction between the substrate and the photoresist or preventing the adverse effects on the substrate of materials used in the photoresist or substances generated during exposure to light of the photoresist. EXAMPLES

[0068] <Synthesis Example 1> 10.00 g of an epoxy group-containing benzene condensed ring compound (product name: EPICLON HP-4700, epoxy value: 165 g / eq., manufactured by DIC Corporation, formula (B-12)), 4.37 g of acrylic acid, 0.56 g of ethyltriphenylphosphonium bromide, and 0.03 g of hydroquinone were added to 34.91 g of propylene glycol monomethyl ether, and the mixture was heated and stirred at 100° C. for 21 hours under a nitrogen atmosphere. 15 g of a cation exchange resin (product name: Dowex (registered trademark) 550A, manufactured by Muromachi Technos Co., Ltd.) and 15 g of an anion exchange resin (product name: Amberlite (registered trademark) 15JWET, manufactured by Organo Corporation) were added to the resulting solution, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, a solution of compound (E) was obtained. The resulting compound (E) corresponds to the formula (E-1), and had a weight average molecular weight Mw of 1,400 as measured by GPC in terms of polystyrene.

[0069] <Synthesis Example 2> 45.22g of propylene glycol monomethyl ether was added to 9.00g of an epoxy group-containing benzene condensed ring compound (product name: EPICLON HP-4700, epoxy value: 162g / eq., manufactured by DIC Corporation, formula (B-12)), 9.84g of N-(4-hydroxyphenyl)methacrylamide, 1.04g of ethyltriphenylphosphonium bromide, and 0.02g of hydroquinone, and the mixture was heated and stirred at 100°C for 25 hours under a nitrogen atmosphere. 20g of a cation exchange resin (product name: Dowex (registered trademark) 550A, manufactured by Muromachi Technos Co., Ltd.) and 20g of an anion exchange resin (product name: Amberlite (registered trademark) 15JWET, manufactured by Organo Corporation) were added to the resulting solution, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, a solution of compound (E) was obtained. The resulting compound (E) corresponds to the formula (E-11), and had a weight average molecular weight Mw of 1,900 as measured by GPC in terms of polystyrene.

[0070] <Synthesis Example 3> 14.00 g of an epoxy group-containing benzene condensed ring compound (product name: EPICLON HP-6000, epoxy value: 239 g / eq., manufactured by DIC Corporation), 4.24 g of acrylic acid, 0.54 g of ethyltriphenylphosphonium bromide, and 0.03 g of hydroquinone were added to 43.89 g of propylene glycol monomethyl ether, and the mixture was heated and stirred at 100° C. for 22 hours under a nitrogen atmosphere. 19 g of a cation exchange resin (product name: Dowex [registered trademark] 550A, manufactured by Muromachi Technos Co., Ltd.) and 19 g of an anion exchange resin (product name: Amberlite [registered trademark] 15JWET, manufactured by Organo Corporation) were added to the resulting solution, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, a solution of compound (E) was obtained. The weight average molecular weight Mw of the resulting compound measured in terms of polystyrene by GPC was 800.

[0071] <Synthesis Example 4> 14.00 g of an epoxy group-containing benzene condensed ring compound (product name: RE-810NM, epoxy value: 221 g / eq., Nippon Kayaku Co., Ltd., formula (B-24)), 4.56 g of acrylic acid, 0.59 g of ethyltriphenylphosphonium bromide, and 0.03 g of hydroquinone were added to 44.77 g of propylene glycol monomethyl ether, and the mixture was heated and stirred at 100°C for 22 hours under a nitrogen atmosphere. 19 g of a cation exchange resin (product name: Dowex [registered trademark] 550A, Muromachi Technos Co., Ltd.) and 19 g of an anion exchange resin (product name: Amberlite [registered trademark] 15JWET, Organo Co., Ltd.) were added to the resulting solution, and the mixture was stirred at room temperature for 4 hours. The mixture was subjected to ion exchange treatment for 1 hour. After separating the ion exchange resin, a solution of compound (E-23) was obtained. The obtained compound (E) corresponds to formula (E-23), and the weight average molecular weight Mw measured by GPC in terms of polystyrene was 900.

[0072] <Comparative Synthesis Example 1> 7.57g of propylene glycol monomethyl ether and 17.67g of propylene glycol monomethyl ether acetate were added to 5.00g of epoxy group-containing aliphatic polyether (trade name: EHPE-3150, epoxy value: 179g / eq., Daicel Corporation, formula (B-11)), 3.11g of 9-anthracene carboxylic acid, 2.09g of benzoic acid, and 0.62g of ethyl triphenylphosphonium bromide, and the mixture was heated under reflux for 13 hours under a nitrogen atmosphere. 16g of cation exchange resin (product name: Dowex [registered trademark] 550A, Muromachi Technos Co., Ltd.) and 16g of anion exchange resin (product name: Amberlite [registered trademark] 15JWET, Organo Corporation) were added to the obtained solution, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, a compound (F) solution was obtained. The obtained compound (F) corresponds to the formula (F-1), and had a weight average molecular weight Mw of 4700 as measured by GPC in terms of polystyrene. [ka]

[0073] <Comparative Synthesis Example 2> 10.00g of diphenylamine, 3.11g of 3-hydroxydiphenylamine, 17.52g of benzoic acid, 24.63g of 2-ethylhexylaldehyde, and 0.45g of methanesulfonic acid were added with 47.40g of propylene glycol monomethyl ether acetate, and the mixture was heated under reflux for 2 hours under a nitrogen atmosphere. The obtained solution was dropped into a mixed solution of concentrated ammonia water / methanol / water = 3 / 10 / 10, and the obtained precipitate was dried under reduced pressure at 60 ° C. 63.12g of propylene glycol monomethyl ether acetate was added to this and dissolved, and then 42g of cation exchange resin (product name: Dowex [registered trademark] 550A, Muromachi Technos Co., Ltd.) and 42g of anion exchange resin (product name: Amberlite [registered trademark] 15JWET, Organo Co., Ltd.) were added, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, a compound (F) solution was obtained. The resulting compound (F) corresponds to the formula (F-2), and had a weight average molecular weight Mw of 10,700 as measured by GPC in terms of polystyrene. [ka]

[0074] <Production Example 1> To 4.19 g of the resin solution (solid content: 25.02 mass%) obtained in Synthesis Example 1, 0.001 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, a fluorosurfactant), 6.62 g of propylene glycol monomethyl ether, and 4.19 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates.

[0075] <Production Example 2> To 6.80 g of the resin solution (solid content: 25.71% by mass) obtained in Synthesis Example 2, 0.002 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, a fluorine-based surfactant), 11.20 g of propylene glycol monomethyl ether, and 6.98 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates.

[0076] <Production Example 3> To 8.13 g of the resin solution (solid content: 25.80 mass%) obtained in Synthesis Example 3, 0.002 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, a fluorine-based surfactant), 13.50 g of propylene glycol monomethyl ether, and 8.37 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates.

[0077] <Production Example 4> To 2.72 g of the resin solution obtained in Synthesis Example 2 (solid content: 25.71% by mass) and 3.07 g of the resin solution obtained in Synthesis Example 4 (solid content: 22.76% by mass), 0.001 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, fluorine-based surfactant), 8.62 g of propylene glycol monomethyl ether, and 5.58 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates.

[0078] <Comparative Manufacturing Example 1> To 6.04 g of the resin solution (solid content: 23.17% by mass) obtained in Comparative Synthesis Example 1, 0.001 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, a fluorine-based surfactant), 11.63 g of propylene glycol monomethyl ether, and 2.33 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates.

[0079] <Comparative Manufacturing Example 2> To 4.63 g of the resin solution (solid content 30.20% by mass) obtained in Comparative Synthesis Example 2, 0.001 g of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, fluorosurfactant), 2.35 g of propylene glycol monomethyl ether, and 13.02 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates. did.

[0080] <Comparative Manufacturing Example 3> To 5.15 g of the resin solution (solid content 23.17% by mass) obtained in Comparative Synthesis Example 1, 0.30 g of tetramethoxymethylglycoluril (product name: POWDERLINK (registered trademark) 1174, manufactured by Nippon Cytec Industries Co., Ltd.) as a thermal crosslinking agent, 0.01 g of pyridinium p-toluenesulfonate as a thermal crosslinking reaction catalyst, 0.001 g of a surfactant (manufactured by DIC Corporation, product name: Megafac (product name) R-40, fluorine-based surfactant), 11.76 g of propylene glycol monomethyl ether, and 2.78 g of propylene glycol monomethyl ether acetate were added to prepare a solution of a composition for forming a coating film for uneven substrates.

[0081] [Curability test] As Examples 1 to 4, the stepped substrate coating film forming compositions prepared in Production Examples 1 to 4 were applied (spin-coated) onto a silicon wafer using a spinner. The compositions were heated on a hot plate at 170°C for 1 minute to form a coating (stepped substrate coating film) with a thickness of 200 nm. The stepped substrate coating film was dry-etched (irradiated with etching gas) using a fluorine-based gas (component: CF4) or an oxygen-based gas (component: O2 / N2) using a plasma dry etching device RIE-10NR manufactured by Samco Co., Ltd., and etched back to a thickness of 100 nm. In order to confirm the solvent peelability of the stepped substrate coating film after dry etching, the stepped substrate coating film was immersed in a mixed solvent of propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate in a ratio of 7:3 for 1 minute, spin-dried, and baked at 100°C for 1 minute. The thickness of the stepped substrate coating film before and after immersion in the mixed solvent was measured using an optical interference thickness meter.

[0082] As Comparative Examples 1 and 2, the compositions for forming coating films for stepped substrates obtained in Comparative Production Examples 1 and 2 were spin-coated onto silicon wafers in the same manner as described above, heated, and then dry-etched back using a plasma dry etching apparatus, and the above-mentioned solvent strippability test was carried out.

[0083] In Comparative Example 3, the composition for forming a coating film for uneven substrates obtained in Comparative Production Example 3 was spin-coated on a silicon wafer and heated at 215°C for 1 minute to form a coating film with a thickness of 200 nm, and the above-mentioned solvent stripping test was carried out without dry etch-back using a plasma dry etching device. The results of the solvent resistance test are shown in Table 1. In Table 1, the initial film thickness refers to the film thickness before the solvent stripping test.

[0084] [Table 1]

[0085] From the above results, in Examples 1 to 4, the stepped substrate coating film did not exhibit solvent peelability (i.e., exhibited solvent resistance) by dry etching (irradiation of etching gas) with a fluorine-based gas or oxygen-based gas. On the other hand, in Comparative Examples 1 and 2, the stepped substrate coating film did not exhibit solvent resistance by dry etching (irradiation of etching gas) with a fluorine-based gas or oxygen-based gas. In other words, the stepped substrate coating film of Examples 1 to 4 can form a hardened film by dry etching (irradiation of etching gas). Since the dry etching device involves irradiation of etching gas, it is believed that the hardening of the stepped substrate coating film occurs due to the plasma components, which are components of the etching gas. In Comparative Example 3, a cured film having solvent resistance was formed without dry etching by adding a thermal crosslinking agent.

[0086] (Planarization test on uneven substrate) To evaluate the step coverage, a 200 nm thick Si substrate was used, which had a dense pattern area (D-1) with a trench width of 50 nm and a pitch of 100 nm, an open area with no pattern, a trench area with a trench width of 230 nm (T-1), and a trench area with a trench width of 800 nm (T-2), on which a 5 nm thick SiN film was deposited. As Examples 1 to 4, the step substrate coating film forming compositions prepared in Production Examples 1 to 4 were applied to the above substrates in a thickness of 400 nm, baked at 170°C for 60 seconds, and dry etched with a fluorine-based gas (component CF4) or an oxygen-based gas (component O2 / N2) in a plasma dry etching device, and etched back to a thickness of 200 nm. The step coverage of the obtained uneven substrate was evaluated by observing the cross-sectional shape using a scanning electron microscope (S-4800) manufactured by Hitachi High-Technologies Corporation, and the planarization property was evaluated by measuring the film thickness difference between D-1, T-1, and T-2 in the open area.

[0087] As Comparative Example 3, the uneven substrate coating film forming composition obtained in Comparative Manufacturing Example 3 was applied to the uneven substrate in a thickness of 200 nm in the same manner as above, and baked at 215°C for 60 seconds. The film thickness difference is shown in Table 2.

[0088] [Table 2]

[0089] From the above results, in Examples 1 to 4 in which a cured film is formed by etching back using plasma etching, the difference in film thickness between D-1, T-1, and T-2 in the open area is smaller than in Comparative Example 3 in which a cured film is formed by baking without etching back using plasma etching. That is, Examples 1 to 4 in which a cured film is formed by plasma etching (irradiation of etching gas) can exhibit better planarization properties than Comparative Example 3 in which a cured film is formed by baking. [Industrial Applicability]

[0090] The composition can be used as a plasma-curable coating film-forming composition for forming an uneven substrate, which has high pattern filling properties, and has planarizing properties that allow for the formation of a coating film on a substrate without causing degassing or thermal shrinkage.

Claims

[Claim 1] Partial structure (I) represented by the following formulas (1-1) to (1-7): 【Chemistry 1】 (In the formula, R １ , R １ａ , R ３ , R ５ａ , and R ６ａ each independently represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms (the alkylene group and the arylene group may be optionally substituted with one or more amide groups or amino groups), an oxygen atom, a carbonyl group, a sulfur atom, -C(O)-NR ａ --, --NR ｂ - or a divalent group consisting of a combination thereof, R ５ each independently represents a nitrogen atom, or a nitrogen atom and an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 40 carbon atoms (the alkylene group and the arylene group may be optionally substituted with one or more amide groups or amino groups), an oxygen atom, a carbonyl group, a sulfur atom, -C(O)-NR ａ - and -NR ｂ - represents a trivalent group consisting of a combination with at least one group selected from the group consisting of R ２ , R ２ａ , R ４ , and R ６ each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a hydrogen atom and an alkylene group having 1 to 10 carbon atoms, an oxygen atom, a carbonyl group, or -C(O)-NR ａ - and -NR ｂ - represents a monovalent group consisting of a combination of at least one group selected from the group consisting of R ａ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, R ｂ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkylcarbonyl group having 1 to 10 carbon atoms, n represents the number of repeat units from 1 to 10; and The dotted lines represent chemical bonds to adjacent atoms.) and a solvent (F).

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