TW201835229A - Film-forming material for resist process, pattern-forming method, and polysiloxane - Google Patents

Abstract

The present invention pertains to a film-forming material for a resist process, containing: a polysiloxane having a first structural unit represented by formula (1) or (2); and a solvent. In formula (1), L1 represents a single bond or a divalent organic group having 1-20 carbon atoms; R1 represents an ethynediyl group or a substituted or unsubstituted ethenediyl group; L2 represents a single bond or an (n+1)-valent organic group having 1-20 carbon atoms; n represents an integer of 1-3; and R2 represents a monovalent group including a polar group. In formula (2), L4 represents a single bond or a divalent organic group having 1-20 carbon atoms; and R4 represents a substituted or unsubstituted ethinyl group, or a substituted or unsubstituted ethenyl group.

Description

Film forming material for resist process, pattern forming method, and polysiloxane

The present invention relates to a film-forming material for a resist process, a pattern forming method, and a polysiloxane.

In the manufacture of semiconductor elements and the like, a pattern forming method is used in which a resist film laminated on a substrate to be processed via an organic anti-reflection film is exposed and developed, and then the obtained resist is used. The etchant pattern is used as a mask to etch the substrate finely.

In recent years, in order to perform finer processing on a substrate, there has been a demand for miniaturization and thinning of a resist pattern as a mask. However, since the difference between the etching rates of the resist film and the organic anti-reflection film is not so large, as the resist pattern used as a mask becomes thinner, it becomes difficult to etch the substrate to be processed.

Therefore, a multilayer resist process is performed in which a silicon-containing film is provided between the resist film and the organic underlayer film, a pattern formed on the resist film is transferred to the silicon-containing film, and then The substrate to be processed is etched by using a silicon-containing film patterned by transfer as a mask (see International Publication No. 2006-126406). The silicon-containing film is required to have excellent solvent resistance and resistance to etching by an oxygen-based gas (hereinafter, also referred to as "oxygen-based gas etching resistance"). [Prior Art Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2006/126406

[Problems to be Solved by the Invention] However, the current miniaturization of resist patterns has developed to a level of line width of 45 nm or less, and the performance requirements have been further improved. The previous multilayer resist process The film-forming materials that can be used to form a silicon-containing film for a resist process cannot meet all of these requirements.

The present invention is based on the above circumstances, and provides a film-forming material for a resist process, a pattern forming method using the same, and a polysiloxane. The film-forming material for a resist process can be formed to maintain solvent resistance, In addition, a silicon-containing film having excellent resistance to etching by an oxygen-based gas and releasability due to alkaline hydrogen peroxide water. [Means for solving problems]

An invention formed to solve the above-mentioned problem is a film-forming material for a resist process, which includes a first structural unit (hereinafter, also referred to as a "structure") represented by the following formula (1) or formula (2): Unit (I) ") polysiloxane (hereinafter, also referred to as" [A] polysiloxane "); and a solvent (hereinafter, also referred to as" [B] solvent "). [Chemical 1] (In formula (1), L ¹ is a single bond or a divalent organic group having 1 to 20 carbon atoms. R ¹ is an acetylene diyl group or a substituted or unsubstituted ethylene diyl group. L ² is a single bond or carbon number (N + 1) -valent organic groups of 1 to 20. n is an integer of 1 to 3. When L ² is a single bond, n is 1. R ² is a monovalent group containing a polar group. In n is In the case of 2 or more, a plurality of R ^{2 are the} same or different. R ^X is a monovalent group not containing an ethylenic carbon-carbon double bond and a carbon-carbon triple bond. I is an integer of 0 to 2. In Formula (2) L ³ is an (m + 1) -valent organic group having 1 to 20 carbon atoms. M is an integer of 1 to 3. R ³ is a monovalent group containing a polar group. When m is 2 or more, a plurality of R ^{3 is the} same or different. L ⁴ is a single bond or a divalent organic group having 1 to 20 carbon atoms. R ⁴ is a substituted or unsubstituted ethynyl group or a substituted or unsubstituted vinyl group)

Another invention formed in order to solve the above-mentioned problem is a pattern forming method including: a step of forming a silicon-containing film on an upper side of a substrate by applying the film-forming material for a resist process; A step of patterning a silicon film; and a step of forming a pattern on the substrate by using the patterned silicon-containing film as a mask.

Another invention which was made in order to solve the said subject is a polysiloxane which has the structural unit represented by said Formula (1) or Formula (2). [Effect of the invention]

According to the film-forming material and pattern forming method for a resist process of the present invention, it is possible to form a silicon-containing film which maintains solvent resistance, and has excellent resistance to oxygen-based gas etching and peelability due to alkaline hydrogen peroxide water. It is possible to form a resist pattern having excellent shape and collapse resistance. The polysiloxane of the present invention can be preferably used as a polysiloxane component of the film-forming material for a resist process. Therefore, these can be preferably used in a multilayer resist process and the like, and can be preferably used in the manufacture of semiconductor devices that are expected to be further refined in the future.

Hereinafter, embodiments of the film-forming material and pattern forming method for a resist process of the present invention will be described.

<Film-forming material for resist process> This film-forming material for resist process (hereinafter, sometimes referred to simply as "film-forming material") contains [A] polysiloxane and [B] solvent. This film-forming material may contain an arbitrary component in the range which does not impair the effect of this invention.

According to this film-forming material, a silicon-containing film having excellent solvent resistance and excellent peel resistance due to oxygen-based gas etching properties and alkaline hydrogen peroxide water can be formed, and furthermore, it can form a resist having excellent shape and collapse resistance. Etching pattern. The reason why the above-mentioned effect is exhibited by the film-forming material having the above-mentioned structure is not necessarily clear, but it can be estimated as follows, for example. That is, the structural unit (I) of [A] polysiloxane has a carbon-carbon double bond or a carbon-carbon triple bond as R ¹ or R ⁴ . The carbon-carbon double bond or the carbon-carbon triple bond has high cross-linking property, and thus a high-density cross-linked structure is formed by heating. As a result, the silicon-containing film formed of the film-forming material has further improved resistance to etching by an oxygen-based gas and releasability due to alkaline hydrogen peroxide water. In addition, since the structural unit (I) of [A] polysiloxane has a monovalent group containing a polar group as R ² or R ³ , its adhesion to a negative resist pattern or the like formed on a silicon-containing film is changed. High, the shape of the negative resist pattern and the like and collapse resistance are further improved. This film-forming material exhibits the above-mentioned effects, and therefore can be preferably used in a resist process. Hereinafter, each component is demonstrated.

<[A] polysiloxane> [A] polysiloxane is a polysiloxane having a structural unit (I).

[Constitutional Unit (I)] The structural unit (I) is a structural unit represented by the following formula (1) or the following formula (2).

[Chemical 2]

In the formula (1), L ¹ is a single bond or a divalent organic group having 1 to 20 carbon atoms. R ¹ is acetylene diyl or substituted or unsubstituted ethylene diyl. L ² is a single bond or an (n + 1) -valent organic group having 1 to 20 carbon atoms. n is an integer of 1 to 3. When L ² is a single bond, n is 1. R ² is a monovalent group containing a polar group. When n is 2 or more, a plurality of R ^{2 are the} same or different. R ^X is a monovalent group containing no ethylenic carbon-carbon double bond and carbon-carbon triple bond. i is an integer from 0 to 2.

In the formula (2), L ³ is a (m + 1) -valent organic group having 1 to 20 carbon atoms. m is an integer of 1 to 3. R ³ is a monovalent group containing a polar group. When m is 2 or more, a plurality of R ^{3 are the} same or different. L ⁴ is a single bond or a divalent organic group having 1 to 20 carbon atoms. R ⁴ is a substituted or unsubstituted ethynyl group or a substituted or unsubstituted vinyl group.

Examples of the divalent organic group having 1 to 20 carbon atoms represented by L ¹ and L ⁴ include a divalent hydrocarbon group having 1 to 20 carbon atoms, and a group having a divalent hetero atom between carbon and carbon of the hydrocarbon group. Group (α), the hydrocarbon group, and a group in which a part or all of hydrogen atoms in the group (α) are substituted with a monovalent heteroatom-containing group, and the like.

Examples of the divalent hydrocarbon group having 1 to 20 carbon atoms include a divalent chain hydrocarbon group having 1 to 20 carbon atoms, a divalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, and a divalent aromatic group having 6 to 20 carbon atoms. Hydrocarbyl, etc.

Examples of the divalent chain hydrocarbon group having 1 to 20 carbon atoms include alkanes such as methane, ethane, propane, and butane, olefins such as ethylene, propylene, and butene, and alkynes such as acetylene, propyne, and butyne. A group obtained by removing two hydrogen atoms.

Examples of the divalent alicyclic hydrocarbon group having 3 to 20 carbon atoms include alicyclic compounds such as cycloalkanes such as cyclopentane and cyclohexane, bridged ring saturated hydrocarbons such as norbornane, adamantane, and tricyclodecane. Cyclic olefins such as saturated hydrocarbons, cyclopentene, cyclohexene, etc., bridged cyclic unsaturated hydrocarbons such as norbornene, tricyclodecene, and other alicyclic unsaturated hydrocarbons, etc. Wait.

Examples of the divalent aromatic hydrocarbon group having 6 to 20 carbon atoms include the two to four aromatic groups of aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene, naphthalene, methylnaphthalene, anthracene, and methylanthracene. A hydrogen atom on a ring or a group obtained by removing hydrogen atoms on two aromatic rings and an alkyl group.

Examples of the hetero atom constituting a group containing a divalent and monovalent hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, and a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Examples of the divalent heteroatom-containing group include -O-, -CO-, -S-, -CS-, -NR'-, groups obtained by combining two or more of these, and the like. . R 'is a hydrogen atom or a monovalent hydrocarbon group. Among these, -O- and -S- are preferred.

Examples of the monovalent heteroatom-containing group include a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, a hydroxyl group, a carboxyl group, a cyano group, an amine group, and a mercapto group. Among these, a halogen atom is preferable, and a fluorine atom is more preferable.

As L ¹ , a single bond and a hydrocarbon group are preferred, a single bond and a chain hydrocarbon group are more preferred, a single bond and an alkanediyl group are more preferred, and a single bond, a methanediyl group, and an ethanediyl group are particularly preferred.

As L ⁴ , a single bond and a hydrocarbon group are preferred, and a single bond is more preferred.

Examples of the substituent of the ethylene diyl group of R ^{1 and} the vinyl group of R ⁴ include a monovalent organic group having 1 to 10 carbon atoms. Examples of the monovalent organic group having 1 to 10 carbon atoms include monovalent organic groups obtained by adding one hydrogen atom to the divalent organic group having 1 to 20 carbon atoms exemplified as the L ¹ and L ⁴ . Those having 1 to 10 carbon atoms and the like. As the substituent of the vinyl diyl group of R ^{1 and} the vinyl group of R ⁴ , a hydrocarbon group is preferred, a chain hydrocarbon group is more preferred, an alkyl group is further preferred, and a methyl group and an ethyl group are particularly preferred.

R ^{1 is} preferably an unsubstituted ethylenediyl group. R ^{4 is} preferably an unsubstituted vinyl group.

Examples of the divalent to tetravalent organic group having 1 to 20 carbon atoms represented by L ² and L ³ include those exemplified as the divalent organic group having 1 to 20 carbon atoms having L ¹ and L ⁴ , A group obtained by removing one or two hydrogen atoms from the divalent organic group.

As n and m, 1 and 2 are preferable, and 1 is more preferable.

When n is 1, L ^{2 is} preferably a single bond and a methanediyl group. When n is 2 or 3, L ^{2 is} preferably a trivalent or tetravalent group obtained by removing 3 or 4 hydrogen atoms from methane.

L ^{3 is} preferably a divalent to tetravalent group obtained by removing two to four hydrogen atoms from methane.

Examples of the monovalent group containing no carbon-carbon double bond and carbon-carbon triple bond represented by R ^X are exemplified as the divalent organic group having 1 to 20 carbon atoms of the above-mentioned L ¹ and L ⁴ . A monovalent organic group formed by adding one hydrogen atom to the group.

As i, 0 and 1 are preferable, and 0 is more preferable.

Examples of the monovalent group containing a polar group represented by R ² and R ³ include a monovalent group containing a hetero atom. R ² and R ^{3 are} preferably a group represented by the following formula (a) or the following formula (b).

[Chemical 3]

In the formulas (a) and (b), * represents a site bonded to L ² or R ¹ in the formula (1) or L ³ in the formula (2). In the formula (a), R ^A is a monovalent hydrocarbon group having 1 to 20 carbon atoms. In the formula (b), R ^B is a monovalent hydrocarbon group having 1 to 20 carbon atoms, or R ^B and R ^a are combined with each other to form a ring structure with 5 to 20 ring members together with these bonded atom chains. . R ^a and R ^b are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, or the number of ring members formed by combining these groups with each other and the carbon atom to which these groups are bonded is 3 to 20 ring structure. R ^c and R ^d are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, or the number of ring members formed by combining these groups with each other and the carbon atom to which these groups are bonded is 3 to 20 ring structure.

The carbon number of R ^A and R ^B and R ^a ~ R ^d is a monovalent hydrocarbon group represented by 1 to 20, for example, as in the L ¹ and L ⁴ carbon atoms exemplified divalent hydrocarbon group having 1 to 20 A monovalent hydrocarbon group formed by adding one hydrogen atom to the group.

As the hydrocarbon group of R ^A , a chain hydrocarbon group and an alicyclic hydrocarbon group are preferable, an alkyl group and a cycloalkyl group are more preferable, and a methyl group, an isopropyl group, a third butyl group, and a 1-methylcyclohexane group are more preferable The -1-yl group is preferably a methyl group. In addition, as the hydrocarbon group of R ^A , a tertiary hydrocarbon group is also preferable, and a tertiary butyl group is particularly preferable.

Examples of the ring structure in which R ^a and R ^b and R ^c and R ^d are bonded to each other to form a ring structure with 3 to 20 ring members together with the carbon atoms to which they are bonded are exemplified as the above-mentioned L ¹ and L ⁴ . The alicyclic structure and the like included in the divalent alicyclic hydrocarbon group having 3 to 20 carbon atoms.

Examples of the ring structure having 5 to 20 ring members formed by bonding R ^B and R ^a together with these bonded atomic chains include, for example, a 1,3-dioxolane structure, and 1,3 -1,3-dioxane structure and the like. Among these, a 1,3-dioxolane structure is preferable. As a group containing a ring structure having 5 to 20 ring members formed by bonding R ^B and R ^a together with these bonded atom chains, 1,3-dioxolyl and 2 are preferred. , 2-dimethyl-1,3-dioxolyl.

As the lower limit of the content ratio of the structural unit (I), it is preferably 0.1 mol%, more preferably 1 mol%, and even more preferably 5 mol% relative to all the structural units constituting [A] polysiloxane. , Particularly preferably 10 mol%, and further preferably 20 mol%. The upper limit of the content ratio is preferably 80 mol%, more preferably 50 mol%, still more preferably 40 mol%, and even more preferably 30 mol%.

Examples of the singular body that provides the structural unit (I) include a compound represented by the following formula.

[Chemical 4]

[Chemical 5]

[Chemical 6]

In the formula, R is a monovalent hydrocarbon group having 1 to 20 carbon atoms.

R is preferably a monovalent chain hydrocarbon group, more preferably an alkyl group, and even more preferably a methyl group and an ethyl group.

[Constitutional Unit (II)] [A] The polysiloxane may have a structural unit (II) represented by the following formula (3).

[Chemical 7]

In the formula (3), R ^Y is a monovalent hydrocarbon group having 1 to 20 carbon atoms. j is an integer of 1 to 3. When j is 2 or more, a plurality of R ^{Y are the} same or different.

Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms represented by R ^Y include a hydrogen atom added to a divalent hydrocarbon group having 1 to 20 carbon atoms exemplified as the L ¹ and L ⁴ . Monovalent hydrocarbon groups and the like. Among these, a chain hydrocarbon group is preferable, an alkyl group is more preferable, and a methyl group is more preferable.

As j, 1 and 2 are preferable, and 1 is more preferable.

Examples of the singular body that provides the structural unit (II) include methyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, and methyl Phenyldimethoxysilane, cyclohexyltrichlorodecane and the like.

In the case where the [A] polysiloxane has the structural unit (II), the lower limit of the content ratio of the structural unit (II) is preferably 0.1 mol relative to all the structural units constituting the [A] polysiloxane. Ear mole%, more preferably 1 mole%, further preferably 10 mole%, even more preferably 20 mole%, and even more preferably 30 mole%. The upper limit of the content ratio is preferably 80 mol%, more preferably 60 mol%, still more preferably 50 mol%, and even more preferably 40 mol%.

[Constitutional Unit (III)] [A] The polysiloxane may have a structural unit (III) represented by the following formula (4).

[Chemical 8]

Examples of the single body that provides the structural unit (III) include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane, tetrahalosilanes such as tetrachlorosilane and tetrabromosilane.

In the case where the [A] polysiloxane has the structural unit (III), the lower limit of the content ratio of the structural unit (III) is preferably 1 mole relative to all the structural units constituting the [A] polysiloxane. Ear mole%, more preferably 10 mole%, further preferably 30 mole%, and even more preferably 60 mole%. The upper limit of the content ratio is preferably 95 mol%, more preferably 90 mol%, still more preferably 85 mol%, and even more preferably 80 mol%. Regarding this film-forming material, when the content ratio of the structural unit (III) is within the above range, the etching resistance of the oxygen-based gas and the peelability by the alkaline hydrogen peroxide water can be further improved.

[Other structural units] [A] As long as the effect of the present invention is not impaired, the polysiloxane may have structural units other than the structural units (I) to (III) as other structural units. Examples of other structural units include structural units derived from silane monomers containing a plurality of silicon atoms, such as hexamethoxydisilanes, bis (trimethoxysilyl) methane, and polydimethoxymethylcarbosilane. . In the case where [A] polysiloxane has other structural units, the upper limit of the content ratio of other structural units is preferably 10 mol%, more preferably 5 mol%, and even more preferably 2 mol%. Especially preferred is 5 mole%.

The lower limit of the content of [A] polysiloxane in the film-forming material is preferably 0.01% by mass, more preferably 0.1% by mass, still more preferably 0.5% by mass, and even more preferably 1% by mass. The upper limit of the content is preferably 20% by mass, more preferably 10% by mass, still more preferably 5% by mass, and even more preferably 3% by mass. When the content of [A] polysiloxane is within the above range, the coatability of the film-forming material can be improved. [A] The polysiloxane may contain only one kind, or may contain two or more kinds.

The lower limit of the weight average molecular weight (Mw) of [A] polysiloxane is preferably 1,000, more preferably 1,300, still more preferably 1,500, and even more preferably 1,700. The upper limit of the Mw is preferably 100,000, more preferably 20,000, even more preferably 7,000, and even more preferably 3,000.

The Mw of [A] polysiloxane in this specification is a gel permeation chromatography (GPC) column (2 "G2000HXL", 1 "G3000HXL", and "G3000HXL") used by Tosoh Corporation. G4000HXL "1), under the analysis conditions of flow rate: 1.0 mL / min, dissolution solvent: tetrahydrofuran, column temperature: 40 ° C, and using monodisperse polystyrene as standard gel permeation chromatography (detector: Differential refractometer).

<[B] Solvent> This film-forming material contains a [B] solvent. Examples of the [B] solvent include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and nitrogen-containing solvents. [B] The solvent may be used alone or in combination of two or more.

Examples of the alcohol-based solvent include monoalcohol-based solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, and isobutanol; ethylene glycol, 1,2-propylene glycol, diethylene glycol, and diethylene glycol. Polyol-based solvents such as propylene glycol.

Examples of the ketone-based solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-isobutyl ketone, and cyclohexanone.

Examples of the ether-based solvent include diethyl ether, isopropyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, and propylene glycol. Monoethyl ether, propylene glycol monopropyl ether, tetrahydrofuran and the like.

Examples of the ester-based solvent include ethyl acetate, γ-butyrolactone, n-butyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and diethylene glycol monomethyl ether. Acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, ethyl propionate , N-butyl propionate, methyl lactate, ethyl lactate and the like.

Examples of the nitrogen-containing solvent include N, N-dimethylformamide, N, N-dimethylacetamide, and N-methylpyrrolidone.

Among these, ether-based solvents and ester-based solvents are preferred, and since they have excellent film-forming properties, ether-based solvents and ester-based solvents having a diol structure are more preferred.

Examples of the ether-based solvent and ester-based solvent having a diol structure include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monopropylene. Ether acetate and the like. Among these, propylene glycol monomethyl ether acetate is particularly preferable.

The lower limit of the content rate of the ether-based solvent and the ester-based solvent having a diol structure in the [B] solvent is preferably 20% by mass, more preferably 60% by mass, still more preferably 90% by mass, and even more preferably 100%. quality%.

The lower limit of the content of the [B] solvent in the film-forming material is preferably 80% by mass, more preferably 90% by mass, and even more preferably 95% by mass. The upper limit of the content is preferably 99% by mass, and more preferably 98% by mass.

<Optional component> This film-forming material may contain arbitrary components, such as a basic compound and an acid generator.

[Basic Compound] The basic compound promotes the curing reaction of the film-forming material, and as a result, the strength and the like of the silicon-containing film formed are improved. In addition, the basic compound enhances releasability by the acidic liquid containing the silicon film. Examples of the basic compound include a compound having a basic amine group, and a base generator that generates a compound having a basic amine group by the action of acid or heat. Examples of the compound having a basic amine group include an amine compound. Examples of the base generator include a sulfonylamine-containing compound, a urea compound, and a nitrogen-containing heterocyclic compound. Specific examples of the amine compound, the amidine-containing compound, the urea compound, and the nitrogen-containing heterocyclic compound include, for example, those described in paragraphs [0079] to [0082] of Japanese Patent Laid-Open No. 2016-27370 Compounds etc.

When the film-forming material contains the basic compound, the content of the basic compound with respect to 100 parts by mass of the [A] polysiloxane is, for example, 1 part by mass or more and 50 parts by mass or less.

[Acid generator] The acid generator is a component that generates an acid by exposure or heating. Since the film-forming material contains an acid generator, the condensation reaction of the [A] polysiloxane compound can also be promoted at a lower temperature (including normal temperature).

Examples of the acid generator that generates an acid by exposure (hereinafter, also referred to as a "photoacid generator") include those described in paragraphs [0077] to [0081] in Japanese Patent Laid-Open No. 2004-168748. Acid generator and so on.

Examples of the acid generator that generates an acid by heating (hereinafter, also referred to as a "thermal acid generator") include the onium salt-based acid generators and 2 as exemplified as photoacid generators in the aforementioned patent documents. , 4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, alkyl sulfonate and the like.

In the case where the film forming material contains an acid generator, the lower limit of the content of the acid generator relative to 100 parts by mass of [A] polysiloxane is preferably 0.01 parts by mass, and more preferably 0.1 parts by mass Further, it is preferably 0.5 parts by mass, and particularly preferably 1 part by mass. The upper limit of the content is preferably 20 parts by mass, more preferably 10 parts by mass, and even more preferably 5 parts by mass.

This film-forming material may contain other arbitrary components in addition to the basic compound and the acid generator. Examples of the other optional components include a surfactant, a radical generator, colloidal silica, colloidal alumina, and an organic polymer. When the film-forming material contains other optional components, the upper limit of the content is preferably 2 parts by mass, and more preferably 1 part by mass, relative to 100 parts by mass of [A] polysiloxane.

<Method for preparing film-forming material for resist manufacturing process> The method for preparing the film-forming material is not particularly limited. For example, it can be prepared by: [A] polysiloxane, [B] solvent, and if necessary Arbitrary components are mixed in a predetermined ratio, and the obtained mixed solution is preferably filtered with a filter having a pore size of 0.2 μm.

The lower limit of the solid content concentration of the film forming material is preferably 0.01% by mass, more preferably 0.1% by mass, still more preferably 0.5% by mass, and even more preferably 1% by mass. The upper limit of the solid content concentration is preferably 20% by mass, more preferably 10% by mass, still more preferably 5% by mass, and even more preferably 3% by mass. The solid content concentration of the film forming material is a value (% by mass) calculated by: calcining the film forming material at 250 ° C. for 30 minutes, thereby measuring the mass of the solid content in the film forming material, The mass of the solid content is divided by the mass of the film-forming material.

<Silicon-containing film> The silicon-containing film obtained from the film-forming material can be formed to maintain solvent resistance, and has excellent resistance to oxygen-based gas etching and peelability due to alkaline hydrogen peroxide water, and further suppresses shape and collapse. Excellent resist pattern. Therefore, the film-forming material can be preferably used as a material for forming a silicon-containing film as an intermediate film in a resist process, particularly in a multilayer resist process. In addition, in the multilayer resist process, it can be particularly preferably used in areas smaller than 90 nm (ArF, ArF in liquid immersion exposure, F ₂ , Extreme Ultraviolet (EUV), nano-imprinting Etc.) Pattern formation using a multilayer resist process.

The silicon-containing film may be formed by applying the film-forming material on a surface of a substrate, an organic lower-layer film, or other lower-layer film to form a coating film, and heat-treating the coating film. And harden it.

Examples of a method for applying the film-forming material include a spin coating method, a roll coating method, and a dipping method. The lower limit of the temperature of the heat treatment is preferably 50 ° C, and more preferably 70 ° C. The upper limit of the temperature is preferably 450 ° C, and more preferably 300 ° C. The lower limit of the average thickness of the formed silicon-containing film is preferably 10 nm, and more preferably 20 nm. The upper limit of the average thickness is preferably 200 nm, and more preferably 150 nm.

<Pattern forming method> The pattern forming method includes a step of forming a silicon-containing film on the upper side of the substrate by applying the film-forming material (hereinafter, also referred to as a "silicon-containing film forming step"); A step of patterning a silicon film (hereinafter, also referred to as a "silicon-containing film patterning step"); and a step of forming a pattern on the substrate using the patterned silicon-containing film as a mask (hereinafter, Also called "substrate pattern forming step").

According to this pattern forming method, since the film-forming material is used, it is possible to form a silicon-containing film that maintains solvent resistance and is excellent in resistance to oxygen-based gas etching and peelability due to alkaline hydrogen peroxide water, thereby forming a shape And a resist pattern having excellent collapse resistance.

The silicon-containing film patterning step may also include: a step of forming a resist pattern on the upper side of the silicon-containing film (hereinafter, also referred to as a "resist pattern forming step"); and the resist A step of etching the silicon-containing film by using a pattern as a mask (hereinafter, also referred to as a "silicon-containing film etching step").

This pattern forming method may also include a step of forming an organic underlayer film on the upper side of the substrate (hereinafter, also referred to as an "organic underlayer film forming step") as required before the step of forming the silicon-containing film. In addition, the pattern forming method may further include a step of removing the silicon-containing film after the silicon-containing film forming step (hereinafter, also referred to as a "silicon-containing film removing step"). Each step will be described below.

<Organic Underlayer Film Formation Step> In this step, an organic underlayer film is formed on the upper side of the substrate. In this pattern forming method, an organic underlayer film forming step may be performed as necessary.

In the pattern forming method, when the organic underlayer film formation step is performed, a silicon-containing film formation step is performed after the organic underlayer film formation step. In the silicon-containing film formation step, the film-forming material is used to form an organic underlayer film. A silicon-containing film is formed thereon.

Examples of the substrate include insulating films such as silicon oxide, silicon nitride, silicon oxynitride, and polysiloxane, and resin substrates. For example, "Black Diamond" by Applied Materials (AMAT), "Silk" by Dow Chemical, and "LKD5109" by JSR An interlayer insulating film such as a wafer covered with a low dielectric insulating film and the like. As this substrate, a patterned substrate such as a wiring groove (shallow groove) or a plug groove (channel) can also be used.

The organic underlayer film is different from a silicon-containing film formed from the film-forming material. The organic underlayer film is used to further supplement the functions of the silicon-containing film and / or the resist film in the formation of the resist pattern, or to provide the necessary predetermined functions (such as anti-reflection) in order to obtain the functions that the films do not have. Properties, coating film flatness, and high etching resistance to fluorine-based gases).

Examples of the organic underlayer film include an antireflection film. Examples of the anti-reflection film-forming material include "NFC HM8006" by JSR.

The organic underlayer film can be formed by applying a composition for forming an organic underlayer film by a spin coating method or the like to form a coating film, and then heating it.

<Si-containing film formation step> In this step, a silicon-containing film is formed on the upper side of the substrate by applying the film-forming material. Through this step, a silicon-containing film is formed on the substrate directly or through other layers such as an organic lower layer film.

The method for forming the silicon-containing film is not particularly limited, and examples thereof include a method in which a film is formed by applying the film-forming material on a substrate or the like by a known method such as a spin coating method, and the coating film is exposed and / or It is formed by heating to harden.

Examples of the radiation used for the exposure include electromagnetic waves such as visible light rays, ultraviolet rays, extreme ultraviolet rays, X-rays, and gamma rays, particle beams such as electron beams, molecular beams, and ion beams.

The lower limit of the temperature when the coating film is heated is preferably 90 ° C, more preferably 150 ° C, and even more preferably 200 ° C. The upper limit of the temperature is preferably 550 ° C, more preferably 450 ° C, and even more preferably 300 ° C. The lower limit of the average thickness of the formed silicon-containing film is preferably 1 nm, more preferably 10 nm, and even more preferably 20 nm. The upper limit of the average thickness is preferably 20,000 nm, more preferably 1,000 nm, and even more preferably 100 nm.

<Silicon-containing film patterning step> In this step, the silicon-containing film is patterned. With this step, the silicon-containing film formed in the silicon-containing film forming step is patterned. Examples of the method for patterning the silicon-containing film include a method including a resist pattern forming step and a silicon-containing film etching step.

[Resist Pattern Forming Step] In this step, a resist pattern is formed on the upper side of the silicon-containing film. With this step, a resist pattern is formed on the upper side of the silicon-containing film formed in the silicon-containing film forming step. Examples of a method for forming a resist pattern include a conventionally known method such as a method using a resist composition and a method using a nanoimprint lithography method. The resist pattern is usually formed of an organic material.

As a method of using the resist composition, for example, a method including a step of forming a resist film on the silicon-containing film by the resist composition (hereinafter, also referred to as " A resist film forming step "); a step of exposing the resist film (hereinafter, also referred to as" exposure step "); and a step of developing the exposed resist film (hereinafter, (Also known as the "development step").

(Resist film formation step) In this step, a resist film is formed on the upper side of the silicon-containing film by a resist composition. A resist film is formed on the upper side of the silicon-containing film by this step.

Examples of the resist composition include a radiation-sensitive resin composition (chemically amplified resist composition) containing a polymer having an acid dissociable group and a radiation-sensitive acid generator, and an alkali-soluble resin and A positive resist composition of a quinone diazide-based photosensitizer, a negative resist composition containing an alkali-soluble resin and a crosslinking agent, and the like. Among these, a radiation-sensitive resin composition is preferred. In the case of using the radiation-sensitive resin composition, a positive pattern can be formed by developing with an alkaline developer, and a negative pattern can be formed by developing with an organic solvent developer. When forming a resist pattern, a double patterning method, a double exposure method, or the like, which is a method for forming a fine pattern, may be appropriately used.

The polymer contained in the radiation-sensitive resin composition may have a structural unit containing a lactone structure, a cyclic carbonate structure, and / or a sultone structure in addition to a structural unit containing an acid-dissociable group, and an alcoholic property A structural unit of a hydroxyl group, a structural unit of a phenolic hydroxyl group, a structural unit of a fluorine atom, and the like. When the polymer has a structural unit containing a phenolic hydroxyl group and / or a structural unit containing a fluorine atom, the sensitivity can be improved when extreme ultraviolet (EUV), an electron beam, or the like is used as radiation during exposure.

The lower limit of the solid content concentration of the resist composition is preferably 0.1% by mass, and more preferably 1% by mass. The upper limit of the solid content concentration is preferably 50% by mass, and more preferably 30% by mass. As the resist composition, a resist composition filtered with a filter having a pore size of about 0.2 μm can be preferably used. In this pattern forming method, a commercially available resist composition may be directly used as the resist composition.

As a method of forming a resist film, the method of apply | coating a resist composition on a silicon containing film, etc. are mentioned, for example. Examples of the method for applying the resist composition include conventional methods such as a spin coating method. When the resist composition is applied, the amount of the applied resist composition is adjusted so that the obtained resist film has a predetermined film thickness.

Regarding the resist film, the coating film of the resist composition can be pre-baked, whereby the solvent in the coating film can be volatilized to form a resist film. The pre-baking temperature is appropriately adjusted according to the type of the resist composition used, and the like, and the lower limit of the pre-baking temperature is preferably 30 ° C, more preferably 50 ° C. The upper limit of the temperature is preferably 200 ° C, and more preferably 150 ° C.

(Exposure Step) In this step, the resist film is exposed. The exposure is performed, for example, by selectively irradiating radiation through a photomask.

The radiation used for the exposure is electromagnetic beams such as visible rays, ultraviolet rays, far ultraviolet rays, X-rays, and gamma rays, particle beams such as electron beams, molecular beams, and ion beams depending on the type of acid generator used in the resist composition. Appropriate choices are made among these. Far ultraviolet and electron beams are preferred, and KrF excimer laser light (248 nm), ArF excimer laser light (193 nm), and F ₂ excimer laser light (wavelength 157 nm) are more preferred. ), Kr ₂ excimer laser light (wavelength 147 nm), ArKr excimer laser light (wavelength 134 nm), EUV (wavelength 13 nm, etc.) and electron beam, and further preferably ArF excimer laser light, EUV and electron beam. Moreover, the method of exposure is not specifically limited, either, It can carry out according to the method performed in the conventionally well-known pattern formation.

(Developing Step) In this step, the exposed resist film is developed. Thereby, a resist pattern is formed.

The development may be an alkali development or an organic solvent development.

Examples of the alkaline developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, and di-n-propyl. Methylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diamine An alkaline aqueous solution in which at least one of basic compounds such as azabicyclo [5.4.0] -7-undecene and 1,5-diazabicyclo [4.3.0] -5-nonene is dissolved. In addition, these alkaline aqueous solutions may be an alkaline aqueous solution to which an appropriate amount of a water-soluble organic solvent such as alcohols such as methanol and ethanol, a surfactant, and the like are added.

Examples of the organic solvent developing solution include solutions containing organic solvents such as a ketone solvent, an alcohol solvent, an ammonium solvent, an ether solvent, and an ester solvent as a main component. Examples of such solvents include the same solvents as the solvents exemplified as the [B] organic solvent. These solvents may be used alone or in combination.

After developing with a developing solution, it is preferable to perform washing and drying, thereby forming a predetermined resist pattern corresponding to the photomask.

[Si-containing film etching step] In this step, the silicon-containing film is etched using the resist pattern as a mask. More specifically, the patterned silicon-containing film is obtained by one or more etchings using the resist pattern formed in the resist pattern forming step as a mask.

The etching may be dry etching or wet etching, but dry etching is preferred.

The dry etching can be performed using, for example, a known dry etching apparatus. The etching gas used in the dry etching can be appropriately selected depending on the elemental composition of the silicon-containing film to be etched, for example, fluorine-based compounds such as CHF ₃ , CF ₄ , C ₂ F ₆ , C ₃ F ₈ , and SF ₆ can be used. Gases; chlorine-based gases such as Cl ₂ and BCl ₃ ; oxygen-based gases such as O ₂ , O ₃ , and H ₂ O; H ₂ , NH ₃ , CO, CO ₂ , CH ₄ , C ₂ H ₂ , C ₂ H ₄ , C ₂ H ₆ , C ₃ H ₄ , C ₃ H ₆ , C ₃ H ₈ , HF, HI, HBr, HCl, NO, NH ₃ , BCl ₃ and other reducing gases; inert gases such as He, N ₂ and Ar, etc. . These gases can also be used in combination. In dry etching of a silicon-containing film, a fluorine-based gas is generally used, and a gas in which an oxygen-based gas and an inert gas are mixed can be preferably used.

<Substrate Pattern Formation Step> In this step, the patterned silicon-containing film is used as a mask, and a pattern is formed on the substrate. This step is usually performed by using the patterned silicon-containing film as a mask and etching the substrate. More specifically, one or more etchings are performed to obtain a patterned substrate, wherein the etching uses a pattern formed on the silicon-containing film obtained in the silicon-containing film etching step as a mask.

When an organic underlayer film is formed on a substrate, a silicon-containing film pattern is used as a mask and the organic underlayer film is etched to form a pattern of the organic underlayer film, and then the organic underlayer film pattern is used as a mask and The substrate is etched to form a pattern on the substrate.

The etching may be dry etching or wet etching, but dry etching is preferred.

The dry etching when forming a pattern on the organic underlayer film can be performed using a known dry etching apparatus. The etching gas used in the dry etching can be appropriately selected depending on the elemental composition of the silicon-containing film and the organic lower film to be etched. For example, CHF ₃ , CF ₄ , C ₂ F ₆ , C ₃ F ₈ , SF can be used. ₆ and other fluorine-based gases; Cl ₂ and BCl ₃ and other chlorine-based gases; O ₂ , O ₃ and H ₂ O and other oxygen-based gases; H ₂ , NH ₃ , CO, CO ₂ , CH ₄ , C ₂ H ₂ , C ₂ H ₄ , C ₂ H ₆ , C ₃ H ₄ , C ₃ H ₆ , C ₃ H ₈ , HF, HI, HBr, HCl, NO, NH ₃ , BCl ₃ and other reducing gases; He, N ₂ , Ar Inert gas and the like may be used in combination. An oxygen-based gas is usually used for dry etching of an organic underlayer film using a pattern containing a silicon film as a mask.

The dry etching when a pattern is formed on a substrate using the organic underlayer film pattern as a mask can be performed using a known dry etching apparatus. The etching gas used in the dry etching can be appropriately selected depending on the elemental composition of the organic underlayer film and the substrate to be etched. For example, the same can be exemplified as the etching gas used in the dry etching of the organic underlayer film. Etching gas and so on. Etching can also be performed by using different etching gases multiple times. Furthermore, in the case where the silicon-containing film remains on the substrate, the organic underlayer film pattern, or the like after the substrate pattern forming step, the silicon-containing film can be removed by performing a silicon-containing film removal step described later.

<Silicon-containing film removal step> In this step, the silicon-containing film is removed after the silicon-containing film formation step. When this step is performed after the substrate etching step, the silicon-containing film remaining on the upper side of the substrate is removed. In addition, this step may also be performed on the silicon-containing film that is patterned or not patterned before the substrate etching step.

Examples of the method of removing the silicon-containing film include a method of dry-etching the silicon-containing film, a method of bringing a liquid such as an alkaline liquid or an acidic liquid into contact with the silicon-containing film, and the like. The liquid is preferably an alkaline liquid.

The dry etching can be performed using a known dry etching apparatus. In addition, as the source gas at the time of dry etching, for example, fluorine-based gases such as CHF ₃ , CF ₄ , C ₂ F ₆ , C ₃ F ₈ , and SF ₆ ; chlorine-based gases such as Cl ₂ and BCl _3, etc. Gases can also be mixed and used.

Examples of the alkaline solution include alkaline hydrogen peroxide water. More specifically, a mixed aqueous solution of ammonia and hydrogen peroxide (25% aqueous ammonia solution / 30% hydrogen peroxide aqueous solution / water = 1/2/40 mixed aqueous solution (SC1)) is particularly preferred. In the case of using alkaline hydrogen peroxide water, the method of wet peeling is not particularly limited as long as it is a method in which a silicon-containing film and alkaline hydrogen peroxide water can be contacted for a certain period of time under heating conditions. Examples include a method of immersing a substrate having a silicon-containing film in heated alkaline hydrogen peroxide water, a method of blowing alkaline hydrogen peroxide water in a heated environment, and heating the basic hydrogen peroxide. A method of applying water. After these methods, the substrate may be washed with water and dried.

The lower limit of the temperature when the silicon-containing film removal step is performed using alkaline hydrogen peroxide water is preferably 40 ° C, and more preferably 50 ° C. The upper limit of the temperature is preferably 90 ° C, and more preferably 80 ° C.

The lower limit of the immersion time in the method for performing the immersion is preferably 0.2 minutes, and more preferably 0.5 minutes. The upper limit of the immersion time is preferably 30 minutes, more preferably 20 minutes, still more preferably 10 minutes, and even more preferably 5 minutes from the viewpoint of suppressing the influence on the substrate. [Example]

Examples will be described below. In addition, the embodiment shown below is an example of a representative embodiment of the present invention, and the scope of the present invention is not narrowly interpreted by this.

The measurement of the solid content concentration of the solution of [A] polysiloxane in this example and the measurement of the weight average molecular weight (Mw) of [A] polysiloxane are performed by the following methods.

[Solid content concentration of solution of [A] polysiloxane] 0.5 g of a solution of [A] polysiloxane was calcined at 250 ° C for 30 minutes, thereby measuring the mass of solid content in 0.5 g of the solution, The solid content concentration (% by mass) of the solution of [A] polysiloxane was calculated.

[Measurement of weight average molecular weight (Mw)] A GPC column (2 "G2000HXL" from Tosoh Corporation, 1 "G3000HXL", and 1 "G4000HXL") was used at a flow rate of 1.0 mL / min, dissolution Solvent: tetrahydrofuran, column temperature: 40 ° C. The measurement was performed by gel permeation chromatography (detector: differential refractometer) using monodisperse polystyrene as a standard.

[Average Thickness of Film] The average thickness of the film was measured using a spectroscopic ellipsometer ("M2000D" by J. A. WOOLLAM).

<Synthesis of [A] polysiloxane> The single bodies used to synthesize [A] polysiloxane are shown below. In addition, in the following synthesis examples, unless otherwise specified in advance, the mass part means a value when the total mass of the single body used is 100 parts by mass. Compound (M-1) to Compound (M-15): Compounds represented by the following formulas (M-1) to (M-15)

[Chemical 9]

[Synthesis Example 1] (Synthesis of polysiloxane (A-1)) In a reaction vessel, a compound represented by the formula (M-1), a compound represented by the formula (M-2), and The compound represented by the formula (M-3) was dissolved in 142 parts by mass of methanol so that the molar ratio became 50/25/25 (mol%) to prepare a single body solution. The inside of the reaction container was set to 60 ° C, and while stirring, 47.9 parts by mass of a 6.25% by mass oxalic acid aqueous solution was added dropwise over 20 minutes. The start of the dropwise addition was set as the start time of the reaction, and the reaction was carried out for 4 hours. After completion of the reaction, the inside of the reaction vessel was cooled to 30 ° C or lower. After 379 parts by mass of propylene glycol monomethyl ether acetate was added to the cooled reaction solution, the alcohol generated by the reaction and the remaining propylene glycol monomethyl ether acetate were removed using an evaporator to obtain polysiloxane. Propylene glycol monomethyl ether acetate solution of alkane (A-1). The Mw of polysiloxane (A-1) was 1,820. The solid content concentration of the propylene glycol monomethyl ether acetate solution of the polysiloxane (A-1) was 11.1% by mass.

[Synthesis Example 2 to Synthesis Example 14] (Polysiloxane (A-2) to Polysiloxane (A-11) and Polysiloxane (a-1) to Polysiloxane (a-3) Synthesis) Polysiloxane (A-2) to polysiloxane (A-11) and polysiloxane (A-11) and polysiloxane (A-11) and A solution of propylene glycol monomethyl ether acetate of polysiloxane (a-1) to polysiloxane (a-3). "-" In Table 1 indicates that the corresponding singular body is not used. Table 1 shows the Mw and the solid content concentration (% by mass) of [A] polysiloxane in the obtained solution of [A] polysiloxane.

[Table 1]

[Preparation of a film-forming material for a resist process] Components other than [A] polysiloxane used to prepare a film-forming material for a resist process are shown below.

[[B] Solvent] B-1: Propylene glycol monomethyl ether acetate

[Example 1] 1.8 parts by mass of (A-1) as [A] polysiloxane (solid content) and 98.2 parts by mass of (B-1) as [B] solvent (including [A] The solvent (B-1) contained in the polysiloxane solution was mixed, and the obtained solution was filtered through a filter having a pore size of 0.2 μm to prepare a film-forming material (J-1) for a resist process.

[Example 2 to Example 11 and Comparative Example 1 to Comparative Example 3] A film for a resist process was prepared in the same manner as in Example 1 except that the components of the types and blending amounts shown in Table 2 below were used. Material (J-2) to film-forming material for resist process (J-11) and film-forming material for resist process (j-1) to film-forming material for resist process (j-3).

<Formation of Silicon-Containing Film> Using a spin coater ("CLEAN TRACK ACT12" of Tokyo Electron Co., Ltd.), each of the prepared resists was prepared by a spin coating method using a spin coating method. The film-forming material is coated on a silicon wafer (substrate). The obtained coating film was heated by a heating plate at 220 ° C. for 1 minute, and then cooled at 23 ° C. for 60 seconds to obtain Examples 1 to 11 and Comparative Examples 1 to 3 in Table 2. A substrate containing a silicon-containing film having an average thickness of 30 nm.

<Evaluation> About the following items, the prepared film-forming material was evaluated by the following method. The evaluation results are shown in Table 2 below. "-" In Table 2 means that it was not evaluated.

[Solvent Resistance] The obtained substrate containing the silicon-containing film was immersed in cyclohexane (20 ° C to 25 ° C) for 10 seconds, and dried. The average thickness of the film before and after immersion was measured. The film thickness change rate (%) when the average thickness of the film before immersion was T ₀ and the average thickness of the film after immersion was T ₁ was determined by the following formula. Film thickness change rate (%) = │T ₁ -T ₀ │ × 100 / T ₀ Regarding solvent resistance, the case where the film thickness change rate is less than 1% is evaluated as "A" (good), and 1% or more Was evaluated as "B" (bad).

[Peelability by Alkaline Hydrogen Peroxide Water] The substrate on which the silicon-containing film was formed was placed in alkaline hydrogen peroxide water (25% by mass ammonia solution / 30% by mass hydrogen peroxide solution / water = 1/2). / 40 (mass ratio) mixed solution (SC1), 60 ° C to 65 ° C) for 5 minutes, and washed with water. The average thickness of the film before and after immersion was measured. When the average thickness before immersion is S ₀ and the average thickness after immersion is S ₁ , the film thickness change rate (%) due to SC1 immersion is determined by the following formula. Film thickness change rate (%) = (S ₀ -S ₁ ) × 100 / S ₀ Regarding the peelability caused by alkaline hydrogen peroxide water, the case where the film thickness change rate was 99% or more was evaluated as "A" ( (Good), and less than 99% of the cases were evaluated as "B" (bad).

[The shape of the resist pattern and the collapse resistance of the resist pattern] The shape of the resist pattern and the collapse resistance of the resist pattern were evaluated by performing the lithographic evaluation shown below.

(Evaluation of lithography, development of organic solvent) The composition for forming an organic lower layer film ("NFC HM8006" by JSR) was applied to a 12-inch silicon wafer by the spin coater, and then Heating was performed at 250 ° C for 60 seconds to form an organic underlayer film having an average thickness of 100 nm. The obtained film-forming material was coated on the organic underlayer film by the spin coater, heated at 220 ° C for 60 seconds, and cooled at 23 ° C for 60 seconds, thereby forming an average thickness of 30 nm. Contains silicon film. Then, a radiation-sensitive resin composition ("ARF AR2772JN" of JSR) was applied to the silicon-containing film by the spin coater, and heated at 90 ° C for 60 seconds and at 23 ° C. After cooling at 30 ° C for 30 seconds, a resist film having an average thickness of 100 nm was formed.

Next, using an ArF liquid immersion exposure device ("S610C" by Nikon Corporation), under the optical conditions of NA: 1.30 and Dipole, a mask size of 40 nm lines / 80 nm pitch pattern formation was masked. Hood for exposure. Heating was performed at 100 ° C for 60 seconds, and cooling was performed at 23 ° C for 30 seconds. Then, butyl acetate was used as a developing solution for 30 seconds to cover the liquid development, and then washed with methyl isobutyl methanol (MIBC), and dried. As a result, a substrate for evaluation on which a resist pattern was formed was obtained.

(Evaluation of the shape of the resist pattern and the collapse suppression property) The shape of the resist pattern and the collapse suppression property were measured as follows. For the measurement and observation of the resist pattern of the substrate for evaluation, a scanning electron microscope ("CG-4000" by Hitachi High-technologies) was used.

In the formation of the resist pattern, the exposure amount is gradually reduced and sequentially exposed. The line width corresponding to the minimum exposure amount for which no collapse of the resist pattern is not confirmed is defined as the minimum pre-collapse size ( nm) as an index of the collapse resistance of the resist pattern. Regarding the collapse resistance of the resist pattern, a case where the size before the minimum collapse was 32 nm or less was evaluated as "A" (good), and a case exceeding 32 nm was evaluated as "B" (bad).

Regarding the shape of the resist pattern, the case where the resist pattern did not have a hem was evaluated as "A" (good), and the case where the pattern was collapsed or the hem was evaluated as "B" (bad).

[Oxygen-resistant gas etching resistance] Using an etching device ("Tactras-Vigus" of Tokyo Electronics Co., Ltd.) at O ₂ = 400 sccm, PRESS. = 25 mT, HF RF = 200 W Under the conditions of LF RF = 0 W, DCS = 0 V, RDC = 50%, and 60 sec, the substrate on which the obtained silicon-containing film was formed was subjected to an etching treatment, and the etching rate was calculated based on the average film thickness before and after the treatment nm / minute) to evaluate the resistance to oxygen-based gas etching. The case where the etching rate is less than 5 nm / minute is "A" (good), and the case where the etching rate is 5 nm / minute or more is "B" (bad).

[Table 2]

From the results in Table 2, it can be seen that the film-forming material of the example can form a resist pattern excellent in shape and collapse resistance, and can form an oxygen-based gas etching resistance and alkaline hydrogen peroxide while maintaining solvent resistance. Silicon-containing film with excellent peelability by water. [Industrial availability]

According to the film-forming material and pattern forming method for a resist process of the present invention, it is possible to form a silicon-containing film which maintains solvent resistance, and has excellent resistance to oxygen-based gas etching and peelability due to alkaline hydrogen peroxide water. It is possible to form a resist pattern having excellent shape and collapse resistance. The polysiloxane of the present invention can be preferably used as a polysiloxane component of the film-forming material for a resist process. Therefore, these can be preferably used in a multilayer resist process and the like, and can be preferably used in the manufacture of semiconductor devices that are expected to be further refined in the future.

Claims (15)

A film-forming material for a resist process, comprising: a polysiloxane having a first structural unit represented by the following formula (1) or formula (2); and a solvent; (In formula (1), L ¹ is a single bond or a divalent organic group having 1 to 20 carbon atoms; R ¹ is an acetylene diyl group or a substituted or unsubstituted ethylene diyl group; L ² is a single bond or carbon number (N + 1) -valent organic groups of 1 to 20; n is an integer of 1 to 3; when L ² is a single bond, n is 1; R ² is a monovalent group containing a polar group; and n is In the case of 2 or more, a plurality of R ^{2 are the} same or different; R ^X is a monovalent group containing no ethylenic carbon-carbon double bond and carbon-carbon triple bond; i is an integer of 0 to 2; in formula (2) , L ³ is a (m + 1) -valent organic group having 1 to 20 carbon atoms; m is an integer of 1 to 3; R ³ is a monovalent group containing a polar group; and when m is 2 or more, a plurality of R ^{3 is the} same or different; L ⁴ is a single bond or a divalent organic group having 1 to 20 carbon atoms; R ⁴ is a substituted or unsubstituted ethynyl group or a substituted or unsubstituted vinyl group). The film-forming material for a resist process according to item 1 of the scope of patent application, wherein R ^{2 in} the formula (1) and R ³ in the formula (2) are represented by the following formula (a) or Formula (b): (In formulas (a) and (b), * represents a site bonded to L ² or R ¹ in formula (1) or L ³ in formula (2); formula (a), R ^a carbon number of a valence of 1 to 20 hydrocarbon group; in the formula (B), R ^B is a C monovalent hydrocarbon group having 1 to 20, or R ^B and R ^a bonded to each other and with the plurality of the bonded chain of atoms form a ring structure member having 5 to 20; R ^a and R ^b are each independently a hydrogen atom or a C monovalent hydrocarbon group having 1 to 20, or indicates that such groups bonded to each other and the junction of the plurality of groups are bonded, Ring structure of 3 to 20 ring members formed by carbon atoms together; R ^c and R ^d are each independently a hydrogen atom or a monovalent hydrocarbon group of 1 to 20 carbon atoms, or these groups are bonded to each other and A ring structure with 3 to 20 ring members formed by the carbon atoms to which the group is bonded). The film-forming material for a resist process according to item 2 of the scope of the patent application, wherein the hydrocarbon group of R ^A in the formula (a) is a chain hydrocarbon group or an alicyclic hydrocarbon group. The film-forming material for a resist process according to item 2 or item 3 of the scope of patent application, wherein R ^B and R ^a in the formula (b) are combined with each other and together with the bonded atomic chains A ring structure with 5 to 20 ring members is formed. The film-forming material for a resist process according to any one of claims 1 to 4, wherein L ² in the formula (1) is a single bond or a methane diyl group. The film-forming material for a resist process according to any one of claims 1 to 5, wherein the polysiloxane has a second structural unit represented by the following formula (3); (In the formula (3), R ^Y is a monovalent hydrocarbon group having 1 to 20 carbon atoms; j is an integer of 1 to 3; and when j is 2 or more, a plurality of R ^{Y are the} same or different). The film-forming material for a resist process according to any one of claims 1 to 6, in which the polysiloxane has a third structural unit represented by the following formula (4); . The film-forming material for a resist process according to any one of claims 1 to 7, wherein the content ratio of the first structural unit to all the structural units constituting the polysiloxane It is 0.1 mol% or more and 50 mol% or less. The film-forming material for a resist process according to any one of claims 1 to 8 of the scope of patent application, which is used in a multilayer resist process. A pattern forming method, comprising: forming a silicon-containing film on an upper side of a substrate by applying a film-forming material for a resist process according to any one of claims 1 to 9 of a patent application scope. A step of patterning the silicon-containing film; and a step of forming the pattern on the substrate by using the patterned silicon-containing film as a mask. The pattern forming method according to item 10 of the scope of the patent application, further comprising a step of removing the silicon-containing film after the silicon-containing film forming step. The pattern forming method according to item 11 of the application, wherein the step of removing the silicon-containing film is to contact an alkaline liquid with the silicon-containing film to remove the silicon-containing film. The pattern forming method according to claim 10, claim 11, or claim 12, wherein the silicon-containing film patterning step includes: a step of forming a resist pattern on an upper side of the silicon-containing film; and And a step of etching the silicon-containing film by using the resist pattern as a mask. The pattern forming method according to any one of the tenth to thirteenth claims, before the step of forming the silicon-containing film, further comprising the step of forming an organic lower layer film on the upper side of the substrate. A polysiloxane having a structural unit represented by the following formula (1) or formula (2), (In formula (1), L ¹ is a single bond or a divalent organic group having 1 to 20 carbon atoms; R ¹ is an acetylene diyl group or a substituted or unsubstituted ethylene diyl group; L ² is a single bond or carbon number (N + 1) -valent organic groups of 1 to 20; n is an integer of 1 to 3; when L ² is a single bond, n is 1; R ² is a monovalent group containing a polar group; and n is In the case of 2 or more, a plurality of R ^{2 are the} same or different; R ^X is a monovalent group containing no ethylenic carbon-carbon double bond and carbon-carbon triple bond; i is an integer of 0 to 2; in formula (2) , L ³ is a (m + 1) -valent organic group having 1 to 20 carbon atoms; m is an integer of 1 to 3; R ³ is a monovalent group containing a polar group; and when m is 2 or more, a plurality of R ^{3 is the} same or different; L ⁴ is a single bond or a divalent organic group having 1 to 20 carbon atoms; R ⁴ is a substituted or unsubstituted ethynyl group or a substituted or unsubstituted vinyl group).