JP2007279135A - Composition for resist base layer film and resist base layer film using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition for a resist base layer film which can reduce resist footing pattern and improve the shape of the pattern, and the resist base layer film using the same. <P>SOLUTION: A predetermined amount of a quaternary ammonium compound is incorporated in the composition for the resist base layer film containing a siloxane-based polymer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a resist underlayer film composition used for a resist underlayer film used as an antireflection film when forming a resist pattern on a substrate, and a resist underlayer film using the same.

In the manufacture of semiconductor elements, pattern formation on a substrate is performed by a lithography process.
In recent years, high integration of semiconductor elements on a circuit board has progressed, but as high integration progresses, a problem is that standing waves generated during the exposure process cause fluctuations in the dimensions of the pattern. As a method for suppressing this standing wave, a method of adding a light absorber to the resist composition, a method of laying an antireflection film on the upper surface of the formed resist layer, or the lower layer of the resist layer, and the like have been proposed.

  In order to form a finer pattern, it is required to reduce the thickness of the antireflection film and the resist layer. However, since it is difficult to perform accurate etching as the resist layer is thinned, it is difficult to process the substrate with high accuracy. Therefore, a resist underlayer film (hard mask) and / or an organic bottom layer having a function as an antireflection film is formed between a film to be processed such as a substrate to be processed and the resist layer to form a substrate. A process of dry etching a film to be processed such as an oxide film or an interlayer insulating film is performed.

For this resist underlayer film, it has been proposed to use a silicon-based material for the composition because of the problem of etching selectivity with the resist layer (see, for example, Patent Documents 1 and 2).
JP 2004-310019 A JP-A-2005-18054

  In the resist underlayer film materials disclosed in Patent Documents 1 and 2, there is a problem that tailing occurs in the resist pattern formed on the resist underlayer film formed from the resist underlayer film material. When such tailing occurs, there arises a problem that the pattern cannot be transferred to a desired shape when the resist underlayer film is etched.

  In view of the above problems, the present invention provides a resist underlayer film composition capable of reducing the tailing of a resist pattern and improving the shape of the pattern, and a resist underlayer film using the same. Objective.

  The present inventors have found that by adding a quaternary ammonium compound to the resist underlayer film composition, it is possible to reduce the tailing of the resist pattern and to improve the shape of the pattern. The invention has been completed.

The present invention provides a resist underlayer film composition containing a siloxane polymer and a quaternary ammonium compound.
Moreover, the resist underlayer film obtained by apply | coating this composition for resist underlayer films and baking at predetermined temperature is provided.

  According to the present invention, by adding a quaternary ammonium compound to the resist underlayer film composition, it is possible to reduce the bottom of the resist pattern and improve the shape of the pattern.

  Hereinafter, embodiments of the present invention will be described in detail. The resist underlayer film composition according to the present invention comprises (A) a siloxane polymer (hereinafter also referred to as (A) component), (B) a quaternary ammonium compound (hereinafter also referred to as (B) component), Containing.

［式中、Ｒ^５は、光吸収基を示し、Ｒ^６は、水素原子、水酸基、炭素数１から６のアルキル基、アルコキシ基を示し、ｒは０又は１である。］ [(A) Siloxane polymer]
The resist underlayer film composition according to the present invention contains (A) a siloxane-based polymer.
In the resist underlayer film composition according to the present invention, the (A) siloxane polymer preferably has a structural unit represented by the general formula (a-1).

[Wherein R ⁵ represents a light absorbing group, R ⁶ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group, and r is 0 or 1. ]

［式中、Ｒ^７は、水素原子、アルキル基、又はカルボニル、エステル、ラクトン、アミド、エーテル、ニトリルから選択される少なくとも１つの官能基を有する１価の有機基を示し、Ｒ^８は、水素原子、水酸基、炭素数１から６のアルキル基、アルコキシ基を示し、ｓは０又は１である。］
これらのシロキサン系重合体は、１種単独で用いてもよいし、複数種混合して用いてもよい。 The light absorbing group is a group having absorption in the wavelength range of 150 to 300 nm. Examples of the light absorbing group include groups having a light absorbing portion such as a benzene ring, an anthracene ring, and a naphthalene ring. The light absorbing portion may be bonded to the Si atom of the main skeleton through an alkylene group having 1 to 20 carbon atoms which may be interrupted by one or more —O— or —O (CO) —. . One or more light absorbing portions such as a benzene ring, an anthracene ring, and a naphthalene ring may be substituted with a substituent such as an alkyl group having 1 to 6 carbon atoms, an alkoxy group, or a hydroxy group. Among these light absorbing groups, a benzene ring is preferable. In addition to the above absorbing group, a group having a light absorbing portion having a Si—Si bond can also be used. Furthermore, these light absorption parts may be contained in the main skeleton of the siloxane polymer. Examples of the light absorbing group include aryl groups such as phenyl group, naphthyl group, methylphenyl group, ethylphenyl group, tolyl group, chlorophenyl group, bromophenyl group, and fluorophenyl group; benzyl group, phenethyl group, naphthylmethyl group, diphenyl Examples include aralkyl groups such as a methyl group, a triphenylmethyl group, and a 1-methyl-1-phenylethyl group. Of these, a phenyl group is preferred. Particularly when a phenyl group is used, light absorption can be improved.
Furthermore, the (A) siloxane-based polymer preferably has at least one structural unit represented by the general formula (a-2).

[Wherein R ⁷ represents a hydrogen atom, an alkyl group, or a monovalent organic group having at least one functional group selected from carbonyl, ester, lactone, amide, ether, and nitrile, and R ⁸ represents hydrogen An atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group is shown, and s is 0 or 1. ]
These siloxane-based polymers may be used alone or as a mixture of two or more.

(A) As a siloxane-type copolymer, it is preferable to use a thing with a mass mean molecular weight of 4000 or more, and it is more preferable to use a thing with 8000 or more. By using the component (A) having a mass average molecular weight of 4000 or more, the film formability of the resist underlayer film formed from the resist underlayer film composition of the present invention can be improved. Further, the mass average molecular weight of the component (A) is preferably 50000 or less, and more preferably 30000 or less. By making the mass average molecular weight of the component (A) 50000 or less, the coating property of the composition for a resist underlayer film of the present invention can be improved.
Moreover, what mixed the siloxane polymer with a mass average molecular weight of less than 4000 with the siloxane polymer with a mass average molecular weight of 4000 or more as said (A) component is preferable. The siloxane polymer having a mass average molecular weight of less than 4000 preferably has a mass average molecular weight of 300 to 3,000. Thereby, the tailing in the resist pattern formed on the resist underlayer film formed from the resist underlayer film composition can be further reduced.
The siloxane-based polymer having a mass average molecular weight of less than 4000 is preferably 10 to 70% by mass and more preferably 30 to 60% by mass in the component (A).

<(A) Method for Producing Siloxane Copolymer>
(A) As a manufacturing method of a siloxane-type copolymer, it can obtain by hydrolyzing and copolymerizing each monomer containing a predetermined structural unit. The amount of water in the hydrolysis reaction is preferably 0.2 to 10 moles per mole of monomer. At this time, known catalysts such as metal chelate compounds, organic acids, inorganic acids, organic bases, and inorganic bases may be appropriately added.

  Specific examples of the metal chelate compound include tetraalkoxytitanium, trialkoxymono (acetylacetonato) titanium, tetraalkoxyzirconium, trialkoxymono (acetylacetonato) zirconium, and the like. Examples of the organic acid include acetic acid, propionic acid, oleic acid, stearic acid, linoleic acid, salicylic acid, benzoic acid, formic acid, malonic acid, phthalic acid, fumaric acid, citric acid, and tartaric acid. Examples of inorganic acids include hydrochloric acid, sulfuric acid, nitric acid, sulfonic acid, methyl sulfonic acid, tosylic acid, trifluoromethane sulfonic acid, and the like.

  Organic bases include pyridine, pyrrole, piperazine, pyrrolidine, piperidine, picoline, trimethylamine, triethylamine, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicyclooctane, diazabicyclononane. , Diazabicycloundecene, tetramethylammonium hydroxide and the like. Examples of the inorganic base include ammonia, sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide and the like.

  Among these, use a basic catalyst such as ammonia or organic amines so as not to open the epoxy group or oxetanyl group contained as a crosslinking group at the time of polymerization, and so as not to mix alkali or metal impurities. Is preferred. Of these, tetraalkylammonium hydroxide is preferably used. Moreover, it is preferable to make the system into an atmosphere of pH 7 or higher so as not to open the epoxy group or the oxetanyl group. These catalysts can be used alone or in combination of two or more.

  As a reaction operation, first, each monomer is dissolved in an organic solvent, and water is added to start a hydrolysis reaction. The catalyst may be added to water or may be added to an organic solvent.

  As the organic solvent used in the reaction, those which are hardly soluble or insoluble in water are preferable. Specifically, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl-2-n-amyl ketone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol Dimethyl ether and mixtures thereof are preferred.

  Next, the catalyst is neutralized and the organic solvent layer is separated and dehydrated. This is because the remaining water causes the condensation reaction of the remaining silanol to proceed. A known dehydration method such as an adsorption method using a salt such as magnesium sulfate or a molecular sieve, or an azeotropic dehydration method while removing the solvent may be used.

  Next, an organic solvent hardly soluble or insoluble in the above water is added, and the organic solvent layer is separated and washed with water to remove the catalyst used for hydrolysis condensation. At this time, you may neutralize as needed. Subsequently, the separated organic solvent layer is dehydrated to obtain (A) a siloxane copolymer.

[(B) Quaternary ammonium compound]
The resist underlayer film composition according to the present invention contains (B) a quaternary ammonium compound. Conventionally, ammonia compounds and amine compounds have been excluded as one of the causes of resist pattern deterioration over time and resist pattern tailing.
However, according to the present invention, by adding a predetermined amount of the quaternary ammonium compound, it is possible to reduce the tailing of the resist pattern formed on the resist underlayer film and to improve the pattern shape.

［式中、Ｒ^１からＲ^４はそれぞれ独立して炭化水素基であり、Ｘ⁻はカウンターアニオンである。］ (B) Specifically, the quaternary ammonium compound is preferably a quaternary ammonium compound represented by the following general formula (b-1).

[Wherein, R ¹ to R ⁴ each independently represent a hydrocarbon group, and X ⁻ represents a counter anion. ]

Examples of the “hydrocarbon group” of R ¹ to R ⁴ include a linear, branched, or cyclic saturated or unsaturated hydrocarbon group. These may have a substituent.
Examples of linear and branched hydrocarbon groups include methyl, methylene, ethyl, ethylene, propyl, propylene, isopropyl, n-butyl, isobutyl, isopropylene and sec-butyl. Group, tertiary butyl group, amyl group, isoamyl group, tertiary amyl group, hexyl group, heptyl group, octyl group, isooctyl group, 2-ethylhexyl group, tertiary octyl group, nonyl group, isononyl group, decyl group, isodecyl Groups and the like.

Examples of the cyclic hydrocarbon group include a cyclic alkyl group and an aryl group.
Examples of the cyclic alkyl group include groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as cycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples thereof include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one hydrogen atom from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Examples of the aryl group include a phenyl group, a naphthyl group, a methylphenyl group, an ethylphenyl group, a tolyl group, a chlorophenyl group, a bromophenyl group, and a fluorophenyl group.

  Examples of the substituent include an OH group and an alkoxy group having 1 to 3 carbon atoms.

Among them, those in which the total carbon number of R ¹ to R ⁴ is 10 or more are preferable. By setting the total number of carbon atoms to 10 or more as described above, tailing of the resist pattern formed on the resist underlayer film can be reduced and the pattern shape can be improved.
Moreover, it is preferable that at least one of R ¹ to R ⁴ is a hydrocarbon group having 8 or more carbon atoms. Thereby, the tailing of the resist pattern formed on the resist underlayer film can be further reduced.
The total carbon number of R ¹ to R ⁴ is preferably 25 or less. Thereby, skirting can be further reduced.

X ⁻ of the counter anion is preferably OH ⁻ , Cl ⁻ , Br ⁻ , F ⁻ , an alkyl carboxylate anion, an aryl carboxylate anion, an aralkyl carboxylate anion, or the like.

Moreover, (B) The addition amount of a quaternary ammonium compound is 0.01 mass part-10 mass parts with respect to 100 mass parts of (A) component, and is 0.1 mass part-5 mass parts. Is more preferable, and the amount is most preferably 0.1 to 3 parts by mass.
By making the addition amount 0.01 parts by mass or more, the crosslinking density of the component (A) can be increased. Moreover, when the addition amount is 10 parts by mass or less, the temporal stability of the resist underlayer film composition can be improved.

  Moreover, the composition for resist underlayer films of the present invention may contain the following components (C), (D), and (E).

[(C) Organic acid]
The resist underlayer film composition according to the present invention preferably contains (C) an organic acid. By adding the organic acid (C), it is possible to prevent deterioration of the resist underlayer film composition with time due to the addition of the component (B).

(C) As organic acid, organic carboxylic acid, organic phosphonic acid, organic sulfonic acid, etc. are mentioned. Examples of the organic carboxylic acid include aliphatic monocarboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, lauric acid, palmitic acid and stearic acid; unsaturated aliphatic monocarboxylic acids such as oleic acid and linoleic acid; oxalic acid, Aliphatic dicarboxylic acids such as malonic acid, succinic acid, adipic acid and maleic acid; oxycarboxylic acids such as lactic acid, gluconic acid, malic acid, tartaric acid and citric acid; aromatics such as benzoic acid, mandelic acid, salicylic acid and phthalic acid Carboxylic acids are mentioned.
As these organic acids, malonic acid is particularly preferable.

Moreover, the addition amount of (C) organic acid is 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of component (A). Most preferably, it is 0.1 to 3 parts by mass.
By making the addition amount 0.01 parts by mass or more, the temporal stability of the resist underlayer film composition can be further improved. Moreover, the inhibition with respect to (B) component can be suppressed by making addition amount into 10 mass parts or less.

The mass ratio of the component (C) and the component (B) is preferably in the range of 10: 100 to 75: 100, and more preferably in the range of 20: 100 to 60: 100.
By making this mass ratio range, the tailing of the resist pattern formed on the resist underlayer film is reduced, the pattern shape is improved, and the temporal stability of the resist underlayer film composition is further improved. Can do.

[(D) Solvent]
The resist underlayer film composition according to the present invention also contains (D) a solvent (hereinafter also referred to as (D) component). Specifically, monohydric alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, alcohols such as ethylene glycol, diethylene glycol, propylene glycol, glycerin, trimethylolpropane, hexanetriol, ethylene glycol monomethyl ether, ethylene Glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopro Ethers such as ether, propylene glycol monobutyl ether, esters such as methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, ketones such as acetone, methyl ethyl ketone, cycloalkyl ketone, methyl isoamyl ketone, ethylene glycol dimethyl ether, Hydroxyl groups of alcohols such as ethylene glycol diethyl ether, ethylene glycol dipropyl ether, ethylene glycol dibutyl ether, propylene glycol dimethyl ether (PGDM), propylene glycol diethyl ether, propylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether All alkyl ether They include alcohols and ethers obtained by.

  These organic solvents may be used alone or in combination of two or more. It is preferable to adjust this solvent so that components other than a solvent may be 0.5 mass% to 10 mass%, and it is more preferable to adjust so that it may become 1 mass% to 6 mass%. By making it within this range, the applicability of the resist underlayer film composition can be improved.

[(E) Crosslinking agent]
The resist underlayer film composition according to the present invention also contains (E) a cross-linking agent (hereinafter also referred to as component (E)). (E) The film formability of the resist underlayer film can be improved by adding a crosslinking agent. As the crosslinking agent, those generally used may be used.

  Specific examples include epoxy compounds such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, and cresol novolak type epoxy resin. In addition, divinylbenzene, divinylsulfone, triacryl formal, glyoxal, polyhydric alcohol acrylic ester or methacrylic ester and the like are also used.

  In addition, compounds having two or more reactive groups such as compounds in which at least two amino groups of melamine, urea, benzoguanamine, and glycoluril are substituted with a methylol group or a lower alkoxymethyl group can be used.

  Examples of the compound in which at least two amino groups of melamine are substituted with a methylol group or a lower alkoxymethyl group include hexamethylol melamine, hexamethoxymethyl melamine, a compound in which 1 to 6 of hexamethylol melamine are methoxymethylated, and a mixture thereof , Hexamethoxyethyl melamine, hexaacyloxymethyl melamine, a compound in which 1 to 5 methylol groups of hexamethylol melamine are acyloxymethylated, or a mixture thereof.

  Examples of the compound in which at least two of the amino groups of urea are substituted with a methylol group or a lower alkoxymethyl group include 1 to 4 methylol groups of tetramethylol urea, tetramethoxymethyl urea, tetramethoxyethyl urea, and tetramethylol urea. Examples thereof include a methoxymethyl group-formed compound or a mixture thereof.

  Compounds in which at least two of the amino groups of benzoguanamine are substituted with a methylol group or a lower alkoxymethyl group include compounds in which one to four methylol groups of tetramethylolguanamine, tetramethoxymethylguanamine, and tetramethylolguanamine are methoxymethylated And mixtures thereof, tetramethoxyethylguanamine, tetraacyloxyguanamine, compounds in which one to four methylol groups of acylmethylolguanamine are acyloxymethylated, and mixtures thereof.

  Examples of the compound in which at least two of the amino groups of glycoluril are substituted with a methylol group or a lower alkoxymethyl group include tetramethylol glycoluril, tetramethoxyglycoluril, tetramethoxymethylglycoluril, and tetramethylolglycoluril methylol groups. From 4 to methoxymethyl group, a mixture thereof, a tetramethylol glycoluril methylol group from 1 to 4 acyloxymethylated compounds, or a mixture thereof.

  These cross-linking agents may be used alone or in combination of two or more. The addition amount of this crosslinking agent is 0.1 to 50 parts by mass, and more preferably 0.5 to 40 parts by mass with respect to 100 parts by mass of component (A).

[(F) Acid generator]
The composition for resist underlayer film according to the present invention may contain (F) an acid generator (hereinafter also referred to as (F) component). (F) By adding an acid generator, crosslinking efficiency can be further improved. Examples of such an acid generator include those that generate an acid by light or heat.

  Examples of the photosensitive acid generator include onium salts, diazomethane derivatives, glyoxime derivatives, bissulfone derivatives, β-ketosulfone derivatives, disulfone derivatives, nitrobenzyl sulfonate derivatives, sulfonate ester derivatives, sulfonate ester derivatives of N-hydroxyimide compounds, and the like. A known acid generator can be used.

  Examples of onium salts include tetramethylammonium trifluoromethanesulfonate, tetramethylammonium nonafluorobutanesulfonate, tetra-n-butylammonium nonafluorobutanesulfonate, tetraphenylammonium nonafluorobutanesulfonate, and tetramethyl p-toluenesulfonate. Ammonium, trifluoromethanesulfonic acid diphenyliodonium, trifluoromethanesulfonic acid (p-tert-butoxyphenyl) phenyliodonium, p-toluenesulfonic acid diphenyliodonium, p-toluenesulfonic acid (p-tert-butoxyphenyl) phenyliodonium, trifluoromethane Triphenylsulfonium sulfonate, trifluoromethanesulfonic acid (p-tert-butoxyphenyl) Phenylsulfonium, trifluoromethanesulfonic acid bis (p-tert-butoxyphenyl) phenylsulfonium, trifluoromethanesulfonic acid tris (p-tert-butoxyphenyl) sulfonium, p-toluenesulfonic acid triphenylsulfonium, p-toluenesulfonic acid (p -Tert-butoxyphenyl) diphenylsulfonium, bis (p-tert-butoxyphenyl) phenylsulfonium p-toluenesulfonate, tris (p-tert-butoxyphenyl) sulfonium p-toluenesulfonate, triphenylsulfonium nonafluorobutanesulfonate , Triphenylsulfonium butanesulfonate, trimethylsulfonium trifluoromethanesulfonate, trimethylsulfone p-toluenesulfonate , Cyclohexylmethyl trifluoromethanesulfonate (2-oxocyclohexyl) sulfonium, p-toluenesulfonate cyclohexylmethyl (2-oxocyclohexyl) sulfonium, trifluoromethanesulfonate dimethylphenylsulfonium, p-toluenesulfonate dimethylphenylsulfonium, trifluoromethane Dicyclohexylphenylsulfonium sulfonate, dicyclohexylphenylsulfonium p-toluenesulfonate, trinaphthylsulfonium trifluoromethanesulfonate, cyclohexylmethyl (2-oxocyclohexyl) sulfonium trifluoromethanesulfonate, (2-norbornyl) methyl trifluoromethanesulfonate (2- Oxocyclohexyl) sulfonium, ethylenebis [Methyl (2-oxocyclopentyl) sulfonium trifluoromethanesulfonate], 1,2'-naphthylcarbonylmethyltetrahydrothiophenium triflate and the like.

  Diazomethane derivatives include bis (benzenesulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (xylenesulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (cyclopentylsulfonyl) diazomethane, bis (n-butylsulfonyl) diazomethane Bis (isobutylsulfonyl) diazomethane, bis (sec-butylsulfonyl) diazomethane, bis (n-propylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, bis (tert-butylsulfonyl) diazomethane, bis (n-amylsulfonyl) diazomethane Bis (isoamylsulfonyl) diazomethane, bis (sec-amylsulfonyl) diazomethane, bis (tert-amylsulfur) Nyl) diazomethane, 1-cyclohexylsulfonyl-1- (tert-butylsulfonyl) diazomethane, 1-cyclohexylsulfonyl-1- (tert-amylsulfonyl) diazomethane, 1-tert-amylsulfonyl-1- (tert-butylsulfonyl) diazomethane Etc.

  Examples of glyoxime derivatives include bis-O- (p-toluenesulfonyl) -α-dimethylglyoxime, bis-O- (p-toluenesulfonyl) -α-diphenylglyoxime, bis-O- (p-toluenesulfonyl)- α-dicyclohexylglyoxime, bis-O- (p-toluenesulfonyl) -2,3-pentanedione glyoxime, bis-O- (p-toluenesulfonyl) -2-methyl-3,4-pentanedione glyoxime, Bis-O- (n-butanesulfonyl) -α-dimethylglyoxime, bis-O- (n-butanesulfonyl) -α-diphenylglyoxime, bis-O- (n-butanesulfonyl) -α-dicyclohexylglyoxime Bis-O- (n-butanesulfonyl) -2,3-pentanedione glyoxime, bis-O- ( -Butanesulfonyl) -2-methyl-3,4-pentanedione glyoxime, bis-O- (methanesulfonyl) -α-dimethylglyoxime, bis-O- (trifluoromethanesulfonyl) -α-dimethylglyoxime, bis -O- (1,1,1-trifluoroethanesulfonyl) -α-dimethylglyoxime, bis-O- (tert-butanesulfonyl) -α-dimethylglyoxime, bis-O- (perfluorooctanesulfonyl)- α-dimethylglyoxime, bis-O- (cyclohexanesulfonyl) -α-dimethylglyoxime, bis-O- (benzenesulfonyl) -α-dimethylglyoxime, bis-O- (p-fluorobenzenesulfonyl) -α- Dimethylglyoxime, bis-O- (p-tert-butylbenzenesulfonyl) α- dimethylglyoxime, bis -O- (xylene sulfonyl)-.alpha.-dimethylglyoxime, bis -O- (camphorsulfonyl)-.alpha.-dimethylglyoxime, and the like.

  Examples of bissulfone derivatives include bisnaphthylsulfonylmethane, bistrifluoromethylsulfonylmethane, bismethylsulfonylmethane, bisethylsulfonylmethane, bispropylsulfonylmethane, bisisopropylsulfonylmethane, bis-p-toluenesulfonylmethane, and bisbenzenesulfonylmethane. Can be mentioned.

Examples of the β-ketosulfone derivative include 2-cyclohexylcarbonyl-2- (p-toluenesulfonyl) propane and 2-isopropylcarbonyl-2- (p-toluenesulfonyl) propane.
Examples of disulfone derivatives include disulfone derivatives such as diphenyl disulfone derivatives and dicyclohexyl disulfone derivatives.
Examples of the nitrobenzyl sulfonate derivative include nitrobenzyl sulfonate derivatives such as p-toluenesulfonic acid 2,6-dinitrobenzyl and p-toluenesulfonic acid 2,4-dinitrobenzyl.
Examples of sulfonic acid ester derivatives include 1,2,3-tris (methanesulfonyloxy) benzene, 1,2,3-tris (trifluoromethanesulfonyloxy) benzene, 1,2,3-tris (p-toluenesulfonyloxy). And sulfonic acid ester derivatives such as benzene.

  Examples of sulfonic acid ester derivatives of N-hydroxyimide compounds include N-hydroxysuccinimide methanesulfonic acid ester, N-hydroxysuccinimide trifluoromethanesulfonic acid ester, N-hydroxysuccinimide ethanesulfonic acid ester, N-hydroxysuccinimide 1-propanesulfonic acid. Ester, N-hydroxysuccinimide 2-propanesulfonic acid ester, N-hydroxysuccinimide 1-pentanesulfonic acid ester, N-hydroxysuccinimide 1-octanesulfonic acid ester, N-hydroxysuccinimide p-toluenesulfonic acid ester, N-hydroxysuccinimide p-methoxybenzenesulfonic acid ester, N-hydroxysuccinimide 2-chloroethanesulfonic acid ester N-hydroxysuccinimide benzenesulfonic acid ester, N-hydroxysuccinimide 2,4,6-trimethylbenzenesulfonic acid ester, N-hydroxysuccinimide 1-naphthalenesulfonic acid ester, N-hydroxysuccinimide 2-naphthalenesulfonic acid ester, N-hydroxy 2-Phenylsuccinimide methanesulfonate, N-hydroxymaleimide methanesulfonate, N-hydroxymaleimide ethanesulfonate, N-hydroxy-2-phenylmaleimide methanesulfonate, N-hydroxyglutarimide methanesulfonate N-hydroxyglutarimide benzene sulfonate, N-hydroxyphthalimide methane sulfonate, N-hydroxy Phthalimidobenzenesulfonic acid ester, N-hydroxyphthalimide trifluoromethanesulfonic acid ester, N-hydroxyphthalimide p-toluenesulfonic acid ester, N-hydroxynaphthalimide methanesulfonic acid ester, N-hydroxynaphthalimide benzenesulfonic acid ester, N-hydroxy -5-norbornene-2,3-dicarboximide methanesulfonate, N-hydroxy-5-norbornene-2,3-dicarboximide trifluoromethanesulfonate, N-hydroxy-5-norbornene-2,3- Dicarboximide p-toluenesulfonic acid ester etc. are mentioned.

  These acid generators may be used alone or in combination of two or more. The addition amount of this acid generator is 0.1 to 50 parts by mass, and more preferably 0.5 to 40 parts by mass with respect to 100 parts by mass of component (A).

  As a manufacturing method of the composition for resist underlayer films which concerns on this invention, it obtains by mixing a required component with (F) component from said (A) component. In addition, it is preferable to filter the obtained resist underlayer film composition with a filter.

[Method for forming resist underlayer film]
In order to form a resist underlayer film using the composition for a resist underlayer film according to the present invention, a spin coater, a slit nozzle coater, etc. on a film to be processed (in some cases, a bottom layer formed on the film to be processed) What is necessary is just to apply | coat using, and to heat after drying. For the heating, a one-step heating or a multi-stage heating method can be used. When the multistage heating method is used, for example, it is preferable to first heat at 100 ° C. to 120 ° C. for 60 seconds to 120 seconds, and then at 200 ° C. to 250 ° C. for 60 seconds to 120 seconds.

  The resist underlayer film thus formed preferably has a thickness of 15 nm to 200 nm. Thereafter, a resist film composition is provided on the resist underlayer film in a thickness of, for example, 100 nm to 300 nm to manufacture a resist film.

[Pattern formation method]
The resist underlayer film formed from the resist underlayer film composition according to the present invention is preferably used as an intermediate layer in a multilayer resist process such as a three-layer resist process.
Examples of the pattern forming method using the resist underlayer film according to the present invention include the following methods.

  As shown in FIG. 1A, the lower layer film composition is applied onto the substrate 20 using a spin coat method or the like, and baked at a predetermined temperature to form the lower layer film 26 (bottom layer). Next, a resist underlayer film composition is applied onto the underlayer film 26 using a spin coating method or the like, and baked at a predetermined temperature to form the resist underlayer film 22. Next, the resist film composition is applied using a spin coating method or the like in the same manner as described above. Next, pre-baking is performed at a predetermined temperature to form a resist film 24. The prebaking conditions are 150 ° C. to 300 ° C., and preferably 30 seconds to 300 seconds.

  Next, the resist underlayer film 22 is etched using the resist film 24 on which the pattern is formed as a mask, and the resist pattern is transferred to the resist underlayer film 22 (see FIG. 1B). The lower layer film 26 is etched using the resist film 24 and the resist lower layer film 22 as a mask, and the resist pattern is transferred to the lower layer film 26 (see FIG. 1C). At this time, the resist film 24 may also be removed by etching at the same time. Next, etching is performed in the same manner as described above to form a pattern on the substrate 20 (see FIG. 1D).

  Since this lower layer film 26 acts as a mask when etching the substrate 20, it is desirable that the lower layer film 26 has high etching resistance and is not required to be mixed with the upper resist lower layer film 22. Alternatively, it is desirable to crosslink with an acid. Specifically, it is preferable to use a resin such as cresol novolak, naphthol novolak, catol dicyclopentadiene novolak, amorphous carbon, polyhydroxystyrene, (meth) acrylate, polyimide, polysulfone.

  Moreover, as a resist composition used for formation of the resist film 24, a well-known thing can be used like a mixture of base resin, an organic solvent, and an acid generator, for example.

  Base resins include polyhydroxystyrene and derivatives thereof, polyacrylic acid and derivatives thereof, polymethacrylic acid and derivatives thereof, copolymers selected from hydroxystyrene, acrylic acid, methacrylic acid and derivatives thereof, cycloolefin and derivatives thereof. Examples thereof include at least one polymer selected from the group consisting of a derivative, maleimide, acrylic acid, and three or more copolymers selected from acrylic acid and derivatives thereof, polynorbornene, and a metathesis ring-opening polymer. In addition, the main skeleton remains after the induction, such as acrylic acid derivatives such as acrylic acid esters, methacrylic acid derivatives such as methacrylic acid derivatives, and alkoxystyrenes such as hydroxystyrene derivatives. Means what

  As a resist for a KrF excimer laser, a copolymer of any one of polyhydroxystyrene, hydroxystyrene, and styrene and any one of acrylic acid ester, methacrylic acid ester, and maleimide N carboxylic acid ester may be mentioned. . Further, as resists for ArF excimer laser, acrylic acid ester-based, methacrylic acid ester-based, alternating copolymerization of norbornene and maleic anhydride, alternating copolymerization of tetracyclododecene and maleic anhydride, polynorbornene-based And metathesis polymerization systems based on ring-opening polymerization, but are not limited to these polymerization polymers.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.

なお、上記表１における略号は以下のとおりである。
上記「部」は「質量部」を示す。

を表す。
（ｃ−１）：マロン酸 [Examples 1 to 5, Comparative Example 1]
<Preparation of composition for resist underlayer film>
The composition for resist underlayer film was adjusted with a mixed solvent of propylene glycol monomethyl ether acetate: ethyl lactate = 6: 4 so that the total of components (A) to (C) shown in Table 1 below was 2.5% by mass. I got a thing.

The abbreviations in Table 1 are as follows.
The above “part” means “part by mass”.

Represents.
(C-1): Malonic acid

<Formation of resist pattern>
A bottom layer (underlayer film) having a thickness of 220 nm is formed on a silicon wafer by applying a composition for forming an underlayer film containing a novolak resin using a conventional resist coater and performing a heat treatment at 250 ° C. for 90 seconds. ) Was formed.
Next, on the bottom layer, the resist underlayer film compositions of Examples 1 to 5 and Comparative Example 1 were applied and subjected to heat treatment at 250 ° C. for 90 seconds to obtain a thickness of 600 mm ( In Examples 4 and 5, a resist underlayer film of 450 mm) was formed. Further, a resist composition was coated on the resist underlayer film (antireflection film) to form a resist layer, and exposed and developed with an ArF excimer laser to form a line pattern.
The resist compositions used in Examples 1 to 5 and Comparative Example 1 were prepared by mixing the following components.

酸発生剤：１）下記式の化合物・・・１．６質量％

酸失活剤：トリエタノールアミン・・・０．３質量％
溶剤：プロピレングリコールモノメチルエーテルアセテート：乳酸エチル＝８：２ Resin: Resin having units (C1: C2: C3 = 3: 5: 2, molecular weight 10,000) represented by the following formula: 100% by mass

Acid generator: 1) Compound of the following formula: 1.6% by mass

Acid quencher: Triethanolamine 0.3% by mass
Solvent: Propylene glycol monomethyl ether acetate: Ethyl lactate = 8: 2

<Evaluation of resist pattern>
The shape of the resist pattern formed above was evaluated. This evaluation was performed by observing the pattern and bottoming state of the resist pattern with an SEM. As a result, each of Examples 1 to 5 showed a good pattern shape with reduced tailing in the resist pattern as compared to Comparative Example 1. Among them, Examples 4 and 5 showed particularly good pattern shapes.

It is the figure which showed the process of forming a resist pattern using the composition for resist underlayer films concerning this invention.

Explanation of symbols

20 Substrate 22 Resist underlayer film 24 Resist film 26 Underlayer film

Claims (8)

  A resist underlayer film composition comprising a siloxane polymer and a quaternary ammonium compound. The composition for a resist underlayer film according to claim 1, wherein the quaternary ammonium compound is represented by the following general formula.

[Wherein, R ¹ to R ⁴ each independently represent a hydrocarbon group, and X ⁻ represents a counter anion. ] The composition for a resist underlayer film according to claim 2, wherein the total carbon number in R ¹ to R ⁴ is 10 or more. The composition for a resist underlayer film according to claim 2 or 3, wherein at least one group of R ¹ to R ⁴ is a hydrocarbon group having 8 or more carbon atoms.   5. The composition for a resist underlayer film according to claim 1, wherein the content of the quaternary ammonium compound is 0.01 part by mass to 10 parts by mass with respect to 100 parts by mass of the siloxane polymer.   The resist underlayer film composition according to any one of claims 1 to 5, comprising an organic acid. The composition for a resist underlayer film according to any one of claims 1 to 6, wherein the siloxane-based polymer has a structural unit represented by the following general formula (a-1).

[Wherein R ⁵ represents a light absorbing group, R ⁶ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group, and r is 0 or 1. ] A resist underlayer film obtained by applying the composition for a resist underlayer film according to claim 1 and baking at a predetermined temperature.

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