WO2008038448A1 - Negative-type resist composition for electron beam, and method for formation of resist pattern - Google Patents

Abstract

Disclosed is a novel negative-type resist composition for electron beam. Also disclosed is a method for formation of a resist pattern using the negative-type resist composition. The negative-type resist composition comprises: (A) at least one compound selected from the group consisting of a hydrolysate of an alkoxysilane compound represented by the general formula (I) and a condensation product of the alkoxysilane compound; and (B) a nonionic acid generator. R1n-Si(OR2)4-n (I) wherein R1 represents a hydrogen atom or an organic group having a valency of 1; R2 represents an organic group having a valency of 1; and n represents an integer of 1 to 3.

Description

 Specification

 Electron beam negative resist composition and resist pattern forming method

 The present invention relates to a negative resist composition for electron beam and a resist pattern forming method.

 In this application, on September 26, 2006, Tsujimoto (the Japanese Patent Application No. 2006-260805, which was filed in this application, claims the priority, and the contents thereof are incorporated herein by reference.

 Background art

 In the case of lithography technology, for example, a resist film made of a resist material is formed on a substrate, for example, and a light or electron beam is passed through a mask in which a predetermined pattern is formed on the resist film. A step of forming a resist pattern having a predetermined shape on the resist film is performed by performing selective exposure with radiation such as, and developing the resist.

 Resist materials that change their properties so that the exposed part dissolves in the developer are positive, resists that do not dissolve in the developer are negative, and resist materials that change their characteristics are negative.

 In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, pattern miniaturization is rapidly progressing due to advances in lithography technology.

 As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, the power used in the past, typically ultraviolet rays such as g-line and i-line, is now in the process of mass production of semiconductor devices using KrF excimer laser and ArF excimer laser.

 In addition, these excimer lasers have shorter wavelength excimer lasers, electron beams, EUV (

 2

 Extreme ultraviolet rays) and X-rays are being studied.

[0003] Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with fine dimensions.

As a resist material satisfying such requirements, a chemically amplified resist containing a base resin whose alkali solubility is changed by the action of an acid and an acid generator that generates an acid upon exposure is used. For example, a positive chemically amplified resist contains an acid dissociable, dissolution inhibiting group as a base resin, contains a resin component that increases alkali solubility by the action of an acid, and an acid generator. Occasionally, when an acid is generated from the acid generator by exposure, the exposed area becomes alkali-soluble.

 On the other hand, a negative chemically amplified resist contains, for example, a resin component having a carboxy group, a crosslinking agent having an alcoholic hydroxyl group, and an acid generator, and an acid generated from the acid generator when forming a resist pattern. As a result of the reaction, the carboxy group of the resin component and the alcoholic hydroxyl group of the cross-linking agent react to change the resin component from alkali-soluble to insoluble.

 Currently, as a base resin for resists used in ArF excimer laser lithography, etc., it has excellent transparency at around 193 nm, and therefore has a structural unit derived from a (meth) acrylate ester in the main chain. (Acrylic resin) is generally used (see, for example, Patent Document 1).

 Patent Document 1: Japanese Patent Laid-Open No. 2003-241385

 Disclosure of the invention

 Problems to be solved by the invention

In the future, it is required to provide a new resist material that can meet the demands for various lithography properties such as high resolution.

 In particular, with further miniaturization of patterns in recent years, there is a demand for a resist material that has better sensitivity to an electron beam having a shorter wavelength than the above excimer laser.

 The present invention has been made in view of the above circumstances, and an object thereof is to provide a novel negative resist composition for electron beams and a resist pattern forming method using the negative resist composition for electron beams. And

 Means for solving the problem

In order to achieve the above object, the present invention employs the following configuration.

That is, the first aspect of the present invention is a condensation of a hydrolyzate of an alkoxysilane compound represented by the following general formula (I) and an alkoxysilane compound represented by the following general formula (I): At least one compound (A) selected from the group consisting of A negative resist composition for an electron beam comprising a crude agent (B).

[0006] [Chemical 1]

[In the formula (I), R ¹ is a hydrogen atom or a monovalent organic group, R ² is a monovalent organic group, and n is an integer of 1 to 3. ]

 [0007] The second aspect of the present invention includes a step of forming a resist film on a substrate using the negative resist composition for an electron beam according to the first aspect (aspect), the resist film And a resist pattern forming method including a step of developing the resist film to form a resist pattern.

In the present specification and claims, an “organic group” is a group containing a carbon atom, and is an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (fluorine Atoms, chlorine atoms, etc.))).

 In the present specification, the “alkyl group” includes straight-chain, branched-chain and cyclic monovalent saturated hydrocarbon groups unless otherwise specified.

 “Lower alkyl group” means an alkyl group having from 5 to 5 carbon atoms.

 “Exposure” means irradiation with an electron beam unless otherwise specified.

 The invention's effect

 The present invention can provide a novel negative resist composition for electron beam and a resist pattern forming method using the negative resist composition for electron beam.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0010] << Negative resist composition for electron beam >>

 The negative resist composition for electron beam of the present invention comprises a hydrolyzate of an alkoxysilane compound represented by the general formula (I) and a condensate of an alkoxysilane compound represented by the following general formula (I). At least one compound selected from the group (A) (hereinafter referred to as component (A)) and a nonionic acid generator (B) (hereinafter referred to as component (B)).

[0011] <(A) component> In the present invention, the component (A) is a hydrolyzate and / or condensate of an alkoxysilane compound represented by the general formula (I).

 In the alkoxysilane compound represented by the general formula (I), the alkoxy group becomes a hydroxyl group by hydrolysis to form an alcohol. Thereafter, two molecules of the alcohol are condensed to form a Si-0-Si network, whereby the component (A) is obtained.

In the general formula (I), R ¹ is a hydrogen atom or a monovalent organic group, and R ² is a monovalent organic group.

In R ² , examples of the monovalent organic group include an alkyl group, a aryleno group, an aryleno group, and a glycidinole group. Of these, alkyl groups and aryl groups are preferred.

 The force, the alkyl group, and the aryl group may have a substituent. As the substituent,

In particular, there are no particular restrictions such as fluorine atoms, straight-chain, branched or cyclic alkyl groups having 1 to 6 carbon atoms.

 Here, in the present specification, “having a substituent” means, for example, that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent. Preferred examples of the alkyl group include those having! To 5 carbon atoms (lower alkyl group), such as a methyl group, an ethyl group, a propyl group, and a butyl group. The alkyl group may be linear or branched, as described above, for example, when a hydrogen atom is substituted with a fluorine atom or the like.

 As the aryl group, those having 6 to 20 carbon atoms are preferred, and examples thereof include a phenyl group and a naphthyl group.

 In the general formula (I), n is an integer of 1 to 3.

[0013] Specific examples of the alkoxysilane compound represented by the general formula (I) include the following.

(i) When n = l, trialkoxysilane compounds such as trimethoxysilane compounds, triethoxysilane compounds, tripropoxysilane compounds (when R ¹ is a hydrogen atom);

Monomethyltrimethoxysilane compound, monomethyltriethoxysilane compound, monomethyltripropoxysilane compound, monoethyltrimethoxysilane compound, monoethyltriethoxy Monoalkyltrialkoxysilane compounds such as silane compounds, monoethyl tripropoxysilane compounds, monopropyltrimethoxysilane compounds, monopropyltriethoxysilane compounds;

 Examples thereof include monophenyltrialkoxysilane compounds such as monophenyltrimethoxysilane compounds and monophenyltriethoxysilane compounds.

(ii) When n = 2, dialkoxysilane compounds such as dimethoxysilane compounds, methoxysilane compounds, dipropoxysilane compounds (when R ¹ is a hydrogen atom);

 Dimethyldimethoxysilane compound, dimethyljetoxysilane compound, dimethyldipropoxysilane compound, jetyldimethoxysilane compound, jetyljetoxysilane compound, jetyldipropoxysilane compound, dipropyldimethoxysilane compound, dipropyljetoxysilane compound And diphenyldialkoxysilane compounds such as dialkyldiphenyldimethoxysilane compounds such as dipropyldipropoxysilane compounds and diphenyljetoxysilane compounds.

(iii) When n = 3, alkoxysilane compounds such as methoxysilane compounds, ethoxysilane compounds, and propoxysilane compounds (when R ¹ is a hydrogen atom);

 Trimethylmethoxysilane compound, trimethylethoxysilane compound, trimethylpropoxysilane compound, triethylmethoxysilane compound, triethylethoxysilane compound, triethylpropoxysilane compound, tripropylmethoxysilane compound, tripropylethoxysilane A trialkylalkoxysilane compound such as a compound;

 And triphenylalkoxysilane compounds such as triphenylmethoxysilane compounds and triphenylethoxysilane compounds.

Among these, trialkoxysilane compounds such as trimethoxysilane compounds, triethoxysilane compounds, tripropoxysilane compounds (when R ¹ is a hydrogen atom); monomethylenotrimethoxysilane compounds, monomethyltriethoxysilane compounds, Particularly preferred is a trialkoxysilane compound (when R ¹ is a hydrogen atom), which is preferably a monomethyltrialkoxysilane compound such as a monomethyltripropoxysilane compound. Of these, triethoxysilane compounds are the most preferred. In the negative resist composition for electron beam of the present invention, the alkoxysilane compound represented by the general formula (I) may be used alone or in combination of two or more. .

 [0016] If the negative resist composition for electron beam of the present invention contains a condensate of an alkoxysilane compound represented by the general formula (I), the mass average molecular weight of the condensate

(Mw) (polystyrene conversion standard by gel permeation chromatography) is preferably 200 to 50,000, more preferably 500 to 10,000, more preferably 1,000 to 3,000. Is more preferable. If it is this range, the applicability | paintability to the board | substrate etc. of the negative resist composition for electron beams can be improved. Further, the presence of the condensate can improve the adhesion between the resist film (cured film) made of a negative resist composition for electron beams and the substrate.

 The condensate of the alkoxysilane compound represented by the general formula (I) is obtained by reacting an alkoxysilane compound as a polymerization monomer in an organic solvent in the presence of an acid catalyst. (Hereinafter, the solution containing the condensate of the alkoxysilane compound obtained here is referred to as “silan-based coating forming coating solution”).

 The alkoxysilane compound used as the polymerization monomer can be used alone or in combination of two or more.

 As the organic solvent, for example, an alkylene glycol dialkyl ether is preferably used because the storage stability (for example, the effect of preventing gelation) of the coating solution for forming a silane-based film is improved.

Such alkylene glycol dialkyl ethers include, for example, ethylene glycol noremethino enoate, ethylene glycol eno chineno ethenore, ethylene glycono dioleno pineolate, ethylene glycol enores butyl enoate, diethylene gluconoresin mino enoate, diethylene glycol. Nore chineno eleenore, diethylene glyconoresin propylene oleate nore, diethylene glucono lesino chineno ethenore, propylene glucono lesino methinore ethenore, propylene glucono lesino teinore, propylene glyconoresin propenole ether, propylene glycol dibutyl ether Etc. Among them, preferred are dialkyl ethers of propylene glycol, particularly preferred propylene. Glycol dimethyl ether.

 These organic solvents may be used alone or in combination of two or more thereof. The amount used is 10 to 30 times the amount of one mole of the alkoxysilane compound.

 [0018] The degree of hydrolysis of the alkoxysilane compound, which is a precondition for condensation, is a force that can be adjusted by the amount of water to be added. Generally, the total moles of the alkoxysilane compound represented by the above general formula (I) It is preferable to add at a ratio of 1 to 10-fold moles relative to the number, more preferably 1.5 to 8-fold moles. When the amount of water added is at least 1 mol, the degree of hydrolysis increases, and the condensation reactivity between alkoxysilane compounds (the above alcohols) improves. On the other hand, when the amount is 10 times or less, gelation is suppressed, and the storage stability of the coating solution for forming a silane-based film is improved.

 [0019] The acid catalyst used in the condensation of the alkoxysilane compound represented by the general formula (I) is not particularly limited, and any of conventionally used organic acids and inorganic acids can be used. Can also be used.

 Examples of the organic acid include organic carboxylic acids such as acetic acid, propionic acid, and butyric acid. Examples of the inorganic acid include hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid and the like.

 The acid catalyst may be added directly to the mixture of the alkoxysilane compound and water, or may be added as an acidic aqueous solution together with water to be added to the alkoxysilane compound.

 [0020] The hydrolysis reaction is usually completed in about 5 to about 100 hours. In addition, at a heating temperature not exceeding 80 ° C. from room temperature, an acid catalyst aqueous solution is dropped into an organic solvent containing one or more alkoxysilane compounds represented by the above general formula (I) to cause a short reaction. It is also possible to complete the reaction in time. The hydrolyzed alkoxysilane compound subsequently undergoes a condensation reaction. As a result, a Si_O_Si network is formed and component (A) is obtained. The component (A) contains a hydrolyzate of an alkoxysilane compound together with a condensate of the alkoxysilane compound.

In the preparation of the electron beam negative resist composition of the present invention, the component (A) is suitably used, for example, in the state of the above-mentioned coating solution for forming a silane-based film. This coating solution for forming a silane-based film is obtained by concentrating a solution obtained by hydrolyzing and condensing an alkoxysilane compound represented by the above general formula (I) or by using an organic solvent (preferably And the like, for example, by diluting with the above-mentioned alkylene glycol dialkyl ether, etc.).

 Such solid content concentration can be measured, for example, by a weight drying method. In the weight drying method, for example, the mass (W1) of the collected coating solution for forming a silane-based film is measured, dried at 500 ° C for 1 hour, and the mass after drying (W2) is obtained. This is a method for calculating the partial concentration.

 Formula: Solid content concentration (% by mass) = W2 / W1 X 100

 Also, the concentration of the coating solution for forming the silane film is approximated as the SiO equivalent concentration of component (A).

 2

 Can be expressed.

 The SiO equivalent concentration is based on the solid content concentration (% by mass) calculated by the above formula.

 2

 (A) It can obtain | require from the structure of a component.

 In the present invention, the SiO equivalent concentration of the coating solution for forming a silane-based film depends on the purpose of use.

 2

 It is adjusted as appropriate, but usually 2 to 15% by mass is preferred. 5 to 12% by mass is preferable.

[0022] <(B) component>

 In the present invention, the component (B) is a nonionic acid generator. This component (B) is a compound that generates an acid in response to an electron beam.

 By containing the component (B), a resist pattern can be obtained by development. This is presumably because acid is generated by electron beam irradiation, and the formation of the Si-O-Si network between components (A) is promoted.

 Further, by containing the component (B), the film stability (PCD: post coating delay) after coating film formation is improved, and the solubility in an alkali developer is improved.

 The component (B) has a small change in solubility in a developer (particularly an alkali developer) and is stable.

[0023] The component (B) is not particularly limited, and those conventionally proposed as acid generators for chemically amplified resists can be used. Examples of such nonionic acid generators include oxime sulfonate acid generators; diazomethane acid generators such as bisalkyl or bisarylsulfonyldiazomethanes and poly (bissulfonyl) diazomethanes. Dalioxime acid generator, bissulfonate acid generator, / 3-ketosulfone acid generator, disulfone acid generator, nitrobenzenosulfonate acid generator, sulfonate ester acid generator, N-hydroxy Various types of imide compounds such as sulfonic acid ester acid generators and imino sulfonate acid generators are known.

 In the present specification and claims, the oxime sulfonate acid generator is a compound (B-1) having at least one group represented by the following general formula (II), and is an electron It has the property of generating acid upon irradiation with rays. Such an oxime sulfonate-based acid generator (B_l) is widely used for chemically amplified resist compositions, and can be arbitrarily selected and used.

[0025] [Chemical 2]

[In the formula (II), R ³¹ and R ³² each independently represents an organic group. ]

[0026] The organic group for R ³¹ is preferably a linear, branched or cyclic alkyl group or aryl group. These alkyl groups and aryl groups may have a substituent. The substituent is not particularly limited, and examples thereof include a fluorine atom, a linear, branched or cyclic alkyl group having 6 to 6 carbon atoms.

 As an alkyl group, carbon number 1 to 20 is preferable. Carbon number 10 is more preferable. Carbon number 1 to 8 is more preferable. Carbon number 1 to 6 is particularly preferable. Is most preferred. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable.

 The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all the hydrogen atoms are halogen atoms. Means an alkyl group substituted with

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. In particular, fluorine atoms are preferred. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.

 The aryl group preferably has 4 to 20 carbon atoms, preferably 4 to 10 carbon atoms, and more preferably 6 to 10 carbon atoms.

 As the aryl group, a partially or completely halogenated aryl group is particularly preferable. A partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is replaced by a halogen atom, and a fully halogenated aryl group means that all hydrogen atoms are halogen atoms. An aryl group substituted with an atom.

As R ³¹ , in particular, an alkyl group having 1 to 4 carbon atoms having no substituent, or 1 carbon atom

~ 4 fluorinated alkyl groups are preferred.

As the organic group for R ³² , a linear, branched or cyclic alkyl group, aryl group or cyan group is preferable. As the alkyl group and aryleno group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.

R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

[0028] More preferable examples of the oxime sulfonate acid generator (B-1) include compounds represented by the following general formula (B-2) or (B-3).

[0029] [Chemical 3]

[In the formula (B_ 2), R ³³ is a cyano group, an alkyl group having no substituent or a halogenated alkyl group, R ³⁴ is an aryl group, and R ³⁵ is an alkyl having no substituent. Group or a halogenated alkyl group. ]

[0030] [Chemical 4]

P ",, · ίβ-3) [In the formula (B-3), R ³⁶ is a cyano group, an alkyl group having no substituent or a halogenated alkyl group, R ³⁷ is a divalent or trivalent aromatic hydrocarbon group, R ³⁸ Is an alkyl group having no substituent or a halogenated alkyl group, and p ′ ′ is 2 or 3. ]

[0031] In the general formula (B_ 2), alkyl or halogenated alkyl group which includes no substituent R ³³ is 1 to carbon atoms: preferably from 10 tool 1 to 8 carbon atoms More preferred C 1-6 is most preferred.

R ³³ is more preferably a fluorinated alkyl group, preferably a halogenated alkyl group.

The fluorinated alkyl group for R ³³ preferably has 50% or more of the hydrogen atom of the alkyl group, more preferably 70% or more, and even more preferably 90% or more. .

[0032] The aryl group of R ³⁴ includes a hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthracyl group, or a phenanthryl group. And a heteroaryl group in which a part of the carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom or a nitrogen atom. Among these, a fluorenyl group is preferable.

The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 4 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.

[0033] The alkyl group or halogenialkyl group having no substituent of R ³⁵ has a carbon number of:!

 A carbon number of 1 to 6 which is preferably 10 is most preferable, and a carbon number of 1 to 6 is more preferable.

R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group, and most preferably a partially or fully fluorinated alkyl group.

The fluorinated alkyl group in R ³⁵ preferably has a hydrogen atom of the alkyl group of 50% or more fluorinated, more preferably 70% or more, and still more preferably 90% or more. This is preferable because the strength of the generated acid is increased. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted. In the general formula (B-3), the alkyl group or halogenated alkyl group having no R ^db substituent does not have the R ³³ substituent in the general formula (B-2). Examples thereof are the same as those for the alkyl group or the halogenated alkyl group.

Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups in which 1 or 2 hydrogen atoms have been further removed from the ⁴ aryl group in the general formula (B — 2).

The alkyl group or halogenated alkyl group having a substituent of R ³⁸ is the same as the alkyl group or halogenated alkyl group having no substituent of R ³⁵ in the general formula (B — 2). Things.

 P ′ ′ is preferably 2.

[0035] Specific examples of the oxime sulfonate acid generator (B_l) include bis (p_toluenesulfonyloxymino) monobenzyl cyanide, bis- (p-chlorobenzenebenzenesulfonyloxy). Simino) monobenzylcyanide, bis- (4-nitrobenzenesulfonyloxyimino) -benzylcyanide, α- (4-12-tallow 2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, bis- ( Benzenesulfonyloxyimino) -4-chlorobenzoylcyanide, α (benzenesulfonyloxyimino) -1,2,4-dichlorobenzilcyanide, α- (benzenesulfonyloxyimino) 2,6 Cyanide, α (Benzenesulfonyloxyimino) 4-methoxybenzylcyanide, a- (2-chlorobenzenesulfonyloxymino) -4 Butoxy cyanide, alpha (benzenesulfonic Honoré Honi Ruo key Consequences mino) Chen 2 I Rua Seto nitrile, a one (4-dodecylbenzene sulfonyl O key Consequences amino) benzyl cyanide, _alpha [([rho toluenesulfonyl O key Consequences Mino) -4-methoxyphenyl] acetonitrile, _α [(dodecylbenzenesulfonoxyximino) _ 4-methoxyphenyl] acetonitrile, a-(tosyloximino) _ 4 _cenyllucyanide, ichiichi (methylsulfonyloxy) Cymino)-1-cyclopentenylacetononitrile, bis- (methylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α- (methylsulfonyloxyximino) -1-cycloheptulacetonitrile , A- (methylsulfonyloxyximino) -1-cyclooctaturacetonitrile, a- (tri Ruorome chill sulfonyl O key Consequences mino) _ 1- cyclopent two Ruasetonitoriru, a - (Torifuruoro methylsulfonyl O key Consequences amino) hexyl § Seto nitrile into single cycloalkyl, a - (Echirusuruhoni Ruoxyimino) -ethylacetonitrile, a (propylsulfonyloxyximino) -open pyracetonitrile, a (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α (cyclohexylsulfonyloxy) Mino) -Cyclohexylacetonitrinole, H- (Cyclohexylsulfonyloxymino) _ 1-Cyclopentulaceto Nitrinole, H- (Ethylsulfonyloxymino) _1-Cyclopentenylacetonitrile -(Isopropylsulfonyloxymino) _ 1-cyclopentenylacetonitrile, a-(n-butylsulfonyloxyimino)-1 -cyclopentenylacetonitrile, _a- (ethylsulfonyloxyimino) mono 1-cyclo to hexenyl Rua Seto nitrile, _a - (isopropyl sulfonyl O carboxymethyl Mino) _ l- cycloheteroalkyl hexenyl Rua Seto nitrile, _a - (n_ butylsulfonyl O key Consequences mino) hexenyl Rua Seto nitrile _ 1 cyclohexane, shed - (Mechirusuruhoni Ruokishiimino) - phenylene Ruasetonitoriru, alpha - (methylsulfonyl Oxymino) _ρ _ methoxyphenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) monophenylacetonitrile, a (trifluoromethylsulfonyloxyimino) -p methoxyphenylacetonitrile, _a (Ethylsulfonyloxyimino) -p methoxyphenylacetonitrile, α (propylsulfonyloxyimino) ρ methylphenylacetonitrile, (methylsulfonyloxyimino) p bromophenylnitrile and the like.

 Further, an oxime sulfonate-based acid generator disclosed in JP-A-9 208554 (paragraphs [0012] to [0014] [Chemical Formula 18] to [Chemical Formula 19]), International Publication No. 04/074242 An oxime sulfonate acid generator disclosed in (Examples 40 to 65 on pages 65 to 85) can also be suitably used.

 Moreover, the following can be illustrated as a suitable thing.

[Chemical 5] [UK 637S

CH— 0 ₂ S— O ~ C = — — S0 ₂ —CH3

 CN CN

 c 『¾s— 0 ~

[0038] Of the above exemplified compounds, the following four compounds are preferred,

[0039] [Chemical 7]

[0040] Examples of the diazomethane acid generator include bis (benzenesulfonyl) diazomethane, bis (p-toluenesulfoninole) diazomethane, bis (xylenesulfoninore) diazomethane,

Diazomethane, bis (n-butylsulfonino) diazomethane, bis (isobutylsulfonyl) diazomethane, bis (sec-butylsulfoninole) diazomethane, bis (n-propylsulfonino) diazomethane, bis (isopropylsulfoninole) diazomethane, bis (Tert-Butylsulfonyl) diazomethane, bis ( _n- amylsulfonyl) diazomethane, bis (isoamylsulfonyl) diazomethane, bis (sec-amylsulfonyl) diazomethane, bis (tert-amylsnorhoninole) diazomethane, 1-cyclohexylsulfonyl _ 1 _ (tert-butylsulfonino) diazomethane, 1-cyclohexylsulfonyl-1-one (tert-aminosulfoninoyl) diazomethane, 1- tert-aminosulfonyl-dione 1- (tert-butylsulfonino) diazomethane And the like.

[0041] Examples of the darioxime acid generator include, for example, bis-O- (p-toluenesulfonyl) _-a -dimethyldaridioxime, bis-l-O- (p-toluenesulfonyl) _α- diphenordridoxime, bis-l-(ρ Toluenesulfonyl) _α -dicyclohexylglyoxime, bis-one Ο— (ρ Toluenesulfonyl) 2, 3 Pentanedione glyoxime, bis 〇 (ρ Toluenesulfonyl) one 2 Methyl 3, 4-pentanedione glyoxime, bis-one Ο— (η-butanesulfonyl) α-dimethyl darilioxime, bis 一 — (η—butanesulfonyl) monodiphenyl daroxime, bis _ (η-butanesulfonyl) -didicyclohexyl glyoxime Bis (1) _ (η-butanesulfonyl) _ 2,3-pentanedione glyoxime, bis (1) _ (η-butanesulfonyl) ) _ 2 _ methyl one 3, 4 —Pentanedione glyoxime, bis ○ (Methanesulfonyl) α-dimethyldario oxime, bis- 一 (trifluoromethanesulfonyl) α-dimethyldarioxime, bis- 0-(1, 1, 1-trifluoroethane Sulfonyl) _α -Dimethyldarioxime, Bis 1-(tert-Butanesulfonyl) 1-Dimethyldarioxime, Bis 10_ (Perfluorooctanesulfonyl) 1-Dimethyldarioxime, Bis 10_ (Cyclohexanesul Phonyl) _-a — dimethyl daroxime, bis _ (benzenesulfonyl) mono-dimethyl oledari oxime, bis _ (p-fluorobenzenesulfonyl) dimethyl diolio oxime, bis _ 0 _ (p _ tert-Butylbenzenesulfonyl) dimethyl dimethyl oxime, bis-O- (xylene sulfonyl) mono dimethyl Examples include rudaroxime, bis-l-O- (force sulfonylsulfonyl) dimethyl daridioxime and the like.

 [0042] Examples of the bissulfone-based acid generator include bisnaphthylsulfonylmethane, bistrinoleolomethinolesnorenoninomethane, bismethinoresnorenoninomethane, bisethinoresnolenomethane, bispropylsulfonyl. Examples include methane, bisisopropylsulfonylmethane, bis-p-toluenesulfonylmethane, and bisbenzenesulfonylmethane.

 [0043] Examples of the β-ketosulfone-based acid generator include 2-cyclohexylcarbonyl-2- (ρtoluenesulfoninole) propane, 2-isopropylcarbonyl 2- (ρtoluenesulfonyl) propane, and the like.

 [0044] Examples of the disulfone-based acid generator include diphenyldisulfone derivatives, dihexyldisulfone derivatives, and the like.

 [0045] Examples of the nitrobenzyl sulfonate acid generator include ρ toluenesulfonic acid 2,6 dinitrobenzyl, ρ toluenesulfonic acid 2,4 dinitrobenzyl, and the like.

 [0046] Examples of the sulfonic acid ester-based acid generator include 1, 2, 3-tris (methanesulfonyloxy) benzene, 1, 2, 3-tris (trifluoromethanesulfonyloxy) benzene, 1, 2, And 3-tris (ρ-toluenesulfonyloxy) benzene.

Examples of the sulfonic acid ester-based acid generator for the の -hydroxyimide compound include Ν-hydroxysuccinimide methanesulfonate, Ν-hydroxysuccinimide trifluoromethanesulfonate, and Ν-hydroxysuccinimide ethanesulfonic acid. Esters, 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 Toluene Sulfonic acid ester, N hydroxysuccinimide p Methoxybenzene sulphonic acid ester, N-hydroxysuccinimide 2 _Ethane sulfonic acid ester, N-hydroxysuccinimide benzene sulphonic acid ester, N-hydroxysuccinimide 2, 4, 6 _Trimethyl Benzenesulfonic acid ester, N —hydroxysuccinimide 1-naphthalenesulfonic acid ester, N hydroxysuccinimide 2 _Naphthalenesulfonic acid Steal, N-hydroxy-1-phenyl succinimide methane sulfonate, N-hydroxy maleimide methane sulfonate, N-hydroxymaleimide ethane sulfonate, N-hydroxy -2-phenyl maleimide methane sulfonate N-hydroxyglutarimide methanesulfonate, N-hydroxyglutarimide benzenesulfonate, N-hydroxyphthalimide methanesulfonate, N-hydroxyphthalimide benzenesulfonate, N-hydroxyphthalimide trifluoromethanesulfonate, N Hydroxyphthalimide p-toluenesulfonic acid ester, N-hydroxynaphthalimide methanesulfonic acid ester, N-hydroxynaphthalimide benzenesulfonic acid Steal, N-hydroxy-5-norbornene 2,3 dicarboximide methanesulfonate, N-hydroxy-5-norbornene 2,3 dicarboximide trifluoromethanesulfonate, N-hydroxy-5 norbornene 2,3 dicarboximide p-toluenesulfonate Etc.

 As the component (B), one type of these acid generators may be used alone, or two or more types may be used in combination.

 In the present invention, since the resist pattern formation is particularly good, an oxime sulfonate acid generator (B-1) having a group represented by the general formula (II) is included as the component (B). Is most preferred.

The content of the component (B) in the electron beam negative resist composition of the present invention is, for example, 3 to 15 mass with respect to the SiO equivalent concentration of the component (A) in the silane-based coating forming coating solution. %, Preferably 5 to 10% by mass. By setting the above range,

Formation of Si-O-Si bonds between components (A) is further promoted, and a resist pattern can be easily obtained by development.

[0049] <Optional component>

 The negative resist composition for electron beam of the present invention further contains a miscible component if desired.

For example, a contrast enhancer, an organic solvent, and the like can be appropriately added and contained.

[0050] The negative resist composition for electron beam of the present invention may contain a contrast enhancer. A contrast enhancer controls the solubility of a resist film (cured film) formed in response to light (electron beam), Z, or heat in the developer, thereby improving the contrast due to the unevenness of the resist film after development. The component to enhance is shown.

 The contrast enhancer is not particularly limited as long as it has the above-described functions, and is not limited to any known compound depending on the composition of the negative resist composition for electron beams, the type of developer, and the like. It is possible to appropriately select from the force.

 Specific examples of the strong contrast enhancer include photoacid generators other than the component (B), thermal acid generators, photobase generators, thermal base generators and the like.

 [0051] The photoacid generator is not particularly limited as long as it is other than the component (B). For example, an onium salt can be used.

[0052] Specific examples of the onium salt include tetramethyl ammonium trifluoromethanesulfonate, tetramethylammonium nonafluorobutanesulfonate, tetra-n-butylammonium nonafluorobutanesulfonate, and nonafluoro Tetraphenylammonium lobutanesulfonate, tetramethylammonium p-toluenesulfonate, diphenylsulfonyl trifluoromethanesulfonate, trifluoromethanesulfonic acid (p-tert-butoxyphenyl), p-toluene Diphenyl fluoride toluene, p-toluenesulfonic acid (p_tert_butoxyphenole), phenylsulfonyl trifluorenylsulfonic acid triphenylsulfonium, trifluoromethanesulfonic acid (p _tert_butoxyphenyl) ) Diphenylsulfonium, Bis (p-tert-butoxyphenyl) trifluoromethanesulfonate, Tris (p-ter t-butoxyphenyl) sulfonium trifluorosulfonate, p-Toluenesulfone Acid triphenylsulfonium, p-toluenesulfonic acid (p-tert-butoxyphenyl) diphenyl sulfone, p-tonoleenesulfonic acid bis (p-tert-butoxyphenyl) phenylsulfonium, p-toluenesulfonic acid tris (p— tert-butoxyphenyl) sulfonium, nonafluorobutans triphenylsulfone sulfone, triphenylsulfonylbutanesulfonate, trimethylsulfonium triphenylmethanesulfonate, trimethyl p-toluenesulfonate Sulfonium, cyclohexylmethyl trifluoromethanesulfonate (2-oxocyclohexyl) sulfone, p-toluenesulfonate cyclohexylmethyl (2-oxocyclohexyl) sulfone, trifluoromethanesulfonic acid Dimethyl phenyl sulfone, p_ Toluene sulfo Dimethyl phenyl sulfone, trifluoromethane sulfonate dicyclohexyl phenyl sulfone, p-toluenesulfonate dicyclohexyl phenyl sulfone, trifluoromethane sulfonate trinaphthyl sulfone, Cyclohexylmethyl trifluoromethylsulfonate (2-oxocyclohexyl) sulfone, Trifluoromethane sulfonate (2-norboninole) methyl (2-oxocyclohexyl) sulfone, Ethylenebis [methyl (2-oxocyclopentyl) Sulphonium trifluoromethanesulfonate], 1,2'-naphthylcarbonylmethyltetrahydrothiophene triflate and the like.

 [0053] The thermal acid generator is a compound that generates an acid in response to heat.

 The thermal acid generator is not particularly limited, and examples thereof include 2, 4, 4, 6-tetrabromocyclohexagenone, benzoin tosylate, 2-nitrobenzene ditosylate, and other alkyl esters of organic sulfonic acid. Alternatively, a conventional thermal acid generator such as a composition containing at least one of these thermal acid generators can be used.

 [0054] The photobase generator is a compound that generates a base in response to light (electron beam).

Examples of photobase generators include, but are not limited to, photoactive power rubamates such as triphenyl methanol, benzyl carbamate and benzoin carbamate; 〇_Strong rubamoyloxime, aromatics, honamide, alpha-latatatam, amides such as N- (2-allyl) amide, and other amides; oxime esters, monoaminoacetophenones, cobalt complexes Can raise 'S' ability. Among these, 2-nitrobenzyl cyclohexyl carbamate, triphenylmethanol, O monostreptyl rubamoyl hydroxylamide, O-strept rubamoyloxime, [[(2, 6-dinitrobenzyl) oxy] carbonyl] cyclo Xylamine, bis [[(2-nitrobenzyl) oxy] carboninole] hexane 1,6-diamine, 4- (methylthiobenzoyl) _ 1 _methyl _ 1 —morpholinoethane, (4-morpholinobenzoyl) ) _ 1 _Benzyl _ 1-dimethylamino propane, N— (2-nitrobenzyloxycarbonyl) pyrrolidine, hexammine cobalt (III) tris (triphenylmethyl borate), 2 _benzyl _ 2-dimethylamino _ 1— ( 4_morpholinophenyl) monobutanone and the like are preferable.

[0055] The thermal base generator is a compound that generates a base in response to heat.

 The thermal base generator is not particularly limited, but examples thereof include 1_methyl_1_ (4-biphenylyl) ethylcarbamate, 1,1-dimethyl_2-cyanethylcarbamate, and the like. Rubamate derivatives of urea; urea derivatives such as urea and N, N-dimethyl_Ν '-methylurea; dihydropyridine derivatives such as 1,4-dihydronicotinamide; quaternized ammonium salts of organic silanes and organic boranes; dicyandiamide Can be used. In addition, guanidinium triacetate acetate, methyldanidine triacetate acetate, potassium trichloroacetate acetate, guanidine phenylsulfonylacetate, guanidine ρ-chlorophenylsulfonylacetate, guanidine ρ-methanesulfonylphenylsulfonylacetate, potassium phenylpropiolate , Guanidine phenylpropiolate, cesium phenylpropiolate, ρ-chloroguanyl guanidine propiolate, ρ-guanidine phenylene-bis-phenylpropiolate, tetramethylammonium phenylsulfonylacetate, Examples include phenylmethyl tetramethylammonium propiolate.

[0056] The compounding amount of the contrast enhancer in the electron beam negative resist composition of the present invention is 0.:! With respect to the SiO equivalent concentration of the component (i) in the silane-based coating forming coating solution.

 2 to 30% by mass is preferable 1 to 15% by mass is more preferable 5 to 10% by mass is more preferable.

By setting the blending amount of the contrast enhancer to 0.1% by mass or more, the effect of the contrast enhancer can be sufficiently obtained, and the resist pattern formed after processing with the developer has sufficient contrast. be able to. On the other hand, the retention stability of the negative resist composition for electron beams can be improved by setting the blending amount of the contrast enhancer to 30% by mass or less. In addition to the improvement, it is possible to prevent a decrease in the amount of film reduction in the exposed area during development and to prevent a decrease in contrast.

[0057] The negative resist composition for an electron beam of the present invention contains an organic solvent (hereinafter sometimes referred to as (S) component) for the purpose of improving coating properties and film thickness uniformity. Is preferred

As the component (S), those conventionally used in general can be used. Specifically, for example, monohydric alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, 3-methoxy_3_methyl_1-butanol, 3-methoxy-1-butanol; methyl_3-methoxy Alkylcarboxylic acid esters such as propionate and ethyl _3_ethoxypropionate; polyhydric alcohols such as ethylene glycol, diethylene glycol and propylene glycol; ethylene glycol monomethyl ethereol, ethylene glycol monoethanolo ethere , Ethylene glycol monopropylene etherate, ethylene glycol / lemonobutinoate ethere, propylene glycol monomonomethylene ether, propylene glycol monoethyl ether, propylene glycol monopropylene Polyhydric alcohol derivatives such as ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate; fatty acids such as acetic acid and propionic acid And ketones such as acetonitrile, methyl ethyl ketone, 2-heptanone, and the like.

 The component (S) may be used alone or in combination of two or more. The amount of the component (S) is not particularly limited, but it is preferable that the concentration of the component (solid content) other than the component (S) is 5 to: 100% by mass 20 to 50% by mass Is more preferable. By making it in the above range, the coating property to the substrate or the like can be improved.

[0058] Further, in the present invention, various additives such as other resins, surface active agents, adhesion assistants and the like can be blended within a range not impairing the effects of the present invention. The additive can be appropriately selected depending on the function desired to be imparted.

[0059] When a surfactant is added, the coating property of the negative resist composition for electron beams is improved, and the flatness of the resulting resist film is also improved. Examples of such surfactants include BM-1000 (trade name; manufactured by BM Chemie); Megafax F142D, F172, F173, and F183 (above, trade names; Dainippon Ink Chemical Co., Ltd.) ); Fluorad FC-135, FC-170C, FC-430, and FC_431 (Product name: Sumitomo 3EM); Surflon S_112, S_113, S_ 131, S_141, and S_145 (trade name; manufactured by Asahi Glass Co., Ltd.); S H-28PA, SH—190, SH—193, SZ—6032, SF—8428, DC—57, and Fluorosurfactants such as D C — 190 (trade name; manufactured by Toray Silicone Co., Ltd.) can be used.

 The ratio in the case of using the surfactant in the negative resist composition for electron beam is usually preferably 5 parts by mass or less with respect to 100 parts by mass of components (solid content) other than the surfactant. More preferably, it is 0.01 to 2 parts by mass.

[0060] When an adhesion assistant is added, the adhesion of the negative resist composition for electron beam to the substrate or the like is improved.

 As such an adhesion assistant, preferably, a silane compound (functional silane coupling agent) having a reactive substituent such as a carboxyl group, a methacryloyl group, an isocyanate group, or an epoxy group is used.

 Specific examples of the functional silane coupling agent include, for example, trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane. Γ-glycidoxypropyl trimethoxysilane, mono (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like.

 In the case of using an adhesion assistant in the negative resist composition for electron beams, it is usually preferred that the ratio is 100 parts by mass or less of components other than the adhesion assistant (solid content), usually 20 parts by mass or less. More preferably 0.05 to 10 parts by mass, particularly preferably 1 to 10 parts by mass.

[0061] <Method for forming resist pattern>

The resist pattern forming method of the present invention includes a step of forming a resist film on a substrate using the negative resist composition for electron beams of the present invention, a step of exposing the resist film, and developing the resist film. And a step of forming a resist pattern. A powerful resist pattern forming method can be performed, for example, as follows. That is, first, a negative resist composition for electron beam is applied onto a substrate such as silicon wafer by a spinner (spin coating method) or the like, and pre-beta (post-applied) is performed at a temperature of 100 to 250 ° C. Beta (PAB)) is applied for 20 to 200 seconds, preferably 60 to 150 seconds, and an electron beam is selectively exposed through a desired mask pattern by, for example, an electron beam drawing machine.

 Thereafter, PEB (post-exposure heating) can be applied for 20 to 200 seconds, preferably 60 to 150 seconds under a temperature condition of 100 to 250 ° C. However, in the present invention, PEB (post-exposure heating) may or may not be applied.

 Subsequently, this is developed using an alkali developer, for example, an aqueous solution of 5 to 20% by mass of tetramethylammonium hydroxide.

 In this way, a resist pattern faithful to the mask pattern can be obtained.

 An organic or inorganic antireflection film may be provided between the substrate and the coating layer of the resist composition.

[0062] As described above, according to the present invention, a novel negative resist composition for electron beam and a resist pattern forming method using the negative resist composition for electron beam can be provided.

 Further, according to the negative resist composition for electron beam of the present invention, for example, a resist film (cured film) formed by applying a negative resist composition for electron beam on a substrate and pre-beta (PAB), Excellent film stability (PCD) after coating and good solubility in alkaline developer.

 The resist pattern obtained using the negative resist composition for electron beams of the present invention can be suitably used as a mold (original) for imprint lithography. Example

 Next, the power to explain the present invention in more detail by way of examples The present invention is not limited to these examples.

<Preparation of negative resist composition for electron beam>

(Example 1) 73.9g (0.45mol) of triethoxysilane with SiO2 concentration of 2% by mass is propyleneglycol

2

 -Noresimechinoreetenore 672 · 9g (6.8 monole) melted quickly and wrinkled.

 Next, a mixture of 24.2 g (l.34 mol) of pure water and 5 ppm of concentrated nitric acid was added dropwise while stirring slowly, and then mixed for about 3 hours, and then allowed to stand at room temperature for 8 days. Got. This solution was distilled under reduced pressure at 120-140mmHg, 40 ° C for 2 hours, converted to SiO

 2 A coating solution for forming a silane-based film having a concentration of 10% by mass and an ethanol concentration of 1% by mass was produced.

[0065] To 100 parts by mass of the coating liquid obtained in the above, the oxime sulfonate acid generator represented by the following chemical formula is used in an amount of 0.7 parts by mass (in the coating liquid). 7 mass%) of the triethoxysilane condensate in terms of SiO concentration)

 2

 A negative resist composition was prepared.

[0066] [Chemical 8]

[0067] <Resist pattern formation>

 The negative resist composition for electron beam obtained in Example 1 obtained above was applied on an 8-inch silicon wafer by spin coating, and then baked (PAB) at 180 ° C. for 120 seconds to form a film. A 300 nm thick resist film (cured film) was formed.

 Next, the resist film (cured film) obtained above was drawn with an electron beam drawing machine (Hitachi HL-1800D, 70 kV high-speed voltage), and drawn with an electron beam, and then the temperature was changed to 23 ° C This was developed with a 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds, washed with water, and then shaken and dried.

 [0068] As a result of the above resist pattern formation, it was confirmed that the negative resist composition for electron beam of Example 1 according to the present invention was able to form a 500 nm L & S pattern.

 [0069] Evaluation of film stability (PCD) after coating

Using the negative resist composition for electron beam of Example 1 and the coating solution for forming a silane-based film alone (hereinafter referred to as “Comparative Example 1”), a resist film ( A cured film) was formed. Next, each resist film was subjected to the conditions shown in Tables:! To 3; that is, following the formation of the resist film (Table 1), and after 15 days (Table 2), the resist film was immersed in water for 10 seconds. After that (Table 3), the film was developed with a 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution at 23 ° C. for 60 seconds, washed with water, and dried by shaking. The PCD was evaluated by measuring the film thickness at this time. The results are shown in Tables!

 [0070] [Table 1]

[0071] [Table 2]

[0072] [Table 3]

[0073] Table: From the results of! To 3, the negative resist composition for electron beam of Example 1 according to the present invention has an onm thickness after development in any case, and development of the unexposed area It was confirmed that the solubility in the liquid was good and the PCD was excellent.

[0074] On the other hand, in Comparative Example 1, which is different from the present invention, a residue was recognized by development processing after 15 days (Table 2), and a residual film was observed by development processing after immersion for 10 seconds in water. (Table 3)

, Confirmed to be inferior to PCD.

 Industrial applicability

[0075] According to the negative resist composition for electron beam of the present invention, for example, a resist film (cured film) formed by applying a negative resist composition for electron beam on a substrate and pre-beta (PAB). Is Excellent film stability (PCD) after coating, and good solubility in alkaline developer.

 The resist pattern obtained using the negative resist composition for electron beam of the present invention can be suitably used as a mold (original) for imprint lithography. Therefore, the present invention is extremely useful industrially.

Claims

Claims [1] At least selected from the group consisting of a hydrolyzate of an alkoxysilane compound represented by the following general formula (I) and a condensate of an alkoxysilane compound represented by the following general formula (I) A negative resist composition for electron beams comprising one kind of compound (A) and a nonionic acid generator (B).

 [Chemical 1]

R ¹ _n —Si (OR ² ) ₄ i _{,,, ξ η}

[In the formula (I), R ¹ is a hydrogen atom or a monovalent organic group, R ² is a monovalent organic group, and n is an integer of:! ]

[2] The negative for an electron beam according to claim 1, wherein the nonionic acid generator (B) includes an oxime sulfonate acid generator (B-1) having a group represented by the following general formula (II). Mold resist composition.

[Chemical 2]

[In the formula (II), R ³¹ and R ³² each independently represents an organic group. ]

[3] A step of forming a resist film on a substrate using the negative resist composition for an electron beam according to claim 1 or 2, a step of exposing the resist film, and developing the resist film to form a resist A resist pattern forming method including a step of forming a pattern.