TWI424265B - Novel compound, manufacturing method thereof, acid generator, resist composition and method of forming resist pattern - Google Patents

Description

Novel compound and its production method, acid generator, photoresist composition and method for forming photoresist pattern

The present invention relates to a novel compound suitable as an acid generator for a photoresist composition and a method for producing the same, and a compound suitable as a precursor of the compound and a method for producing the same, an acid generator, a photoresist composition and a photoresist pattern The method of formation.

This case is based on the special wish 2007-187593 proposed by the Japan Patent Office on July 18, 2007, and the priority of 2007-257492, which was proposed by the Japan Patent Office on October 1, 2007. The contents are used in the manual.

In the lithography technique, for example, a photoresist film obtained from a photoresist material is formed on a substrate, and the photoresist film is selectively exposed to radiation such as light or electron lines by forming a mask of a specific pattern. The development process is carried out to form the photoresist film into a photoresist pattern having a specific shape. The portion of the exposure which is changed to have a property of dissolving in the developer is referred to as a positive type, and the portion of the photoresist which is changed to have a property of not being dissolved in the developer is referred to as a negative type.

In recent years, in the manufacture of semiconductor elements or liquid crystal display elements, with the advancement of the lithography etching technology, the pattern has been rapidly refined.

The method of miniaturization is generally performed in such a manner as to shorten the wavelength of the exposure light source. Specifically, ultraviolet rays represented by g lines and i lines are conventionally used. However, KrF excimer lasers or ArF excimer lasers are now being used for mass production of semiconductor components. Further, F ₂ excimer lasers, electron beams, EUV (extreme ultraviolet rays), or X-rays having shorter wavelengths for the aforementioned excimer laser have also been studied.

The photoresist material is intended to have sensitivity to the aforementioned exposure light source, and has lithographic etching characteristics such as resolution which can reproduce a fine-size pattern. The photoresist material which satisfies the above requirements generally has a chemically amplified photoresist which contains a base resin which changes the alkali solubility based on the action of an acid, and an acid generator which generates an acid by exposure. For example, a positive type chemically amplified photoresist is a resin containing an acid-based action as a base resin to increase alkali solubility, and an acid generator component which is formed by exposure to an acid when formed in a photoresist pattern. The agent generates an acid, and the exposed portion forms an alkali developer to be soluble.

The base resin of the chemically amplified photoresist is a polyhydroxystyrene (PHS) highly transparent to KrF excimer laser (248 nm) or a resin protected by an acid-dissociable dissolution inhibiting group (PHS). Resin). However, since the PHS-based resin has an aromatic ring such as a benzene ring, transparency to a shorter wavelength of 248 nm, for example, light of 193 nm is still insufficient. Therefore, a chemically amplified photoresist using a PHS-based resin as a base resin component has disadvantages such as low resolution, for example, a process using 193 nm light. Therefore, at present, the base resin for the photoresist used in the ArF excimer laser lithography etching has a good transparency in the vicinity of 193 nm, so that the main chain is generally derived from (meth) acrylate. The resin of the structural unit (acrylic resin). In the case of a positive type, the above-mentioned resin is mainly a (meth) acrylate which contains a tertiary alkyl ester type acid dissociable dissolution inhibiting group containing an aliphatic polycyclic group. The structural unit to be derived, for example, a resin mainly containing a structural unit derived from 2-alkyl-2-adamantyl (meth) acrylate or the like (for example, Patent Document 1).

Further, "acrylic acid ester" means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methyl methacrylate bonded to the α-position. "(Meth)acrylate" means an acrylate having a hydrogen atom bonded to the α-position, and one or both of the methyl methacrylate bonded to the α-position. "(Meth)acrylic acid" means one or both of acrylic acid having a hydrogen atom bonded to the α-position and one or both of the methyl methacrylate bonded to the α-position.

Further, various acid-generating agents used in chemically amplified photoresists have been proposed, such as sulfonium-based acid generators such as iodonium salts or phosphonium salts.

[Patent Document 1] JP-A-2003-241385

The anion portion of the above sulfonium salt-based acid generator is generally a perfluoroalkylsulfonate ion. The perfluoroalkyl chain of the anion is preferably longer than the diffusion of an acid after exposure. However, a perfluoroalkyl chain having 6 to 10 carbon atoms is difficult to decompose, and a nonafluorobutanesulfonic acid ion or the like is used in consideration of conservability of a living body and safety in handling. Therefore, there is an urgent need for a suitable novel compound for the acid generator for the photoresist composition.

The present invention is provided in view of the above-mentioned circumstances, to provide a A novel compound suitable as an acid generator for a photoresist composition and a method for producing the same, which are suitable as a compound of the precursor of the compound, a method for producing the same, a method for forming an acid generator, a photoresist composition, and a photoresist pattern.

In order to achieve the above object, the present invention adopts the following constitution.

In other words, the first aspect of the present invention is a compound represented by the following formula (b1-1) (hereinafter, also referred to as a compound (B1)).

Wherein R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and when n1 is 1, R ¹ and R ³ may be bonded to each other, and The carbon atom of R ¹ bond and the carbon atom of R ³ bond form a ring of 3 to 7 member ring structure at the same time, and A is a ring of 3 to 7 ring structure which can form a ring with the A bond. The valence group may have a substituent, and R ² may be an aromatic group which may have a substituent, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or may have a substituent A linear or branched alkenyl group having 2 to 10 carbon atoms, n is 0 or 1, and Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine.

The second aspect of the present invention is a method for producing a compound represented by the formula (b1-1-1) (hereinafter, also referred to as a method for producing the compound (B1-1)), which comprises the following The step of reacting a compound represented by the formula (I) with a compound represented by the following formula (II) under a copper catalyst to obtain a compound represented by the following formula (b1-1-1) .

Wherein A is a divalent group which can form a ring of a 3 to 7 member ring structure simultaneously with the sulfur atom bonded to the A bond, the ring may have a substituent, and R ² is an aromatic group which may have a substituent a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or a linear or branched alkenyl group having 2 to 10 carbon atoms which may have a substituent, n is 0. Or 1, Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine, and R ¹ is an aryl group or an alkyl group which may have a substituent independently.

The third aspect of the present invention is a compound represented by the following formula (I) (hereinafter also referred to as a compound (I)).

[wherein R ² is an aromatic group which may have a substituent, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or a carbon number of 2 to 10 which may have a substituent a linear or branched alkenyl group, n is 0 or 1, Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine, and R ¹ is an independently aryl group which may have a substituent or alkyl〕.

The fourth aspect of the present invention is a method for producing a compound represented by the following formula (I) (hereinafter also referred to as a method for producing the compound (I)), which comprises the following formula (I- 1) A step of reacting a compound represented by the following formula (1-2) with a compound represented by the following formula (1-2) to obtain a compound represented by the following formula (I).

[wherein R ² is an aromatic group which may have a substituent, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or a carbon number of 2 to 10 which may have a substituent a linear or branched alkenyl group, n is 0 or 1, Y ¹ is a C 1 to 4 alkyl group which may be substituted by fluorine, M ⁺ is an alkali metal ion, and R ¹ is independently An aryl group or an alkyl group having a substituent, and R ⁷ is an alkyl group or a fluorinated alkyl group].

The fifth aspect of the present invention is the acid generator formed by the compound (B1) of the first aspect.

A sixth aspect of the present invention is a photoresist composition which is a substrate component containing a change in solubility of an alkali developer via an action of an acid. (A), and a photoresist composition of the acid generator component (B) which generates an acid by exposure, the acid generator component (B) is a compound represented by the following formula (b1-1) An acid generator (B1) is formed.

[Wherein, R ¹ is an optionally substituted aryl group or an alkyl group of, R ³ is a hydrogen atom or an alkyl group, N1 is 0 or 1, n1 is 1, R ¹ and R ³ may be bonded to each other, and the The carbon atom of R ¹ bond and the carbon atom of R ³ bond form a ring of 3 to 7 member ring structure at the same time, and A is a ring of 3 to 7 ring structure which can form a ring with the A bond. The valence group may have a substituent, and R ² may be an aromatic group which may have a substituent, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or may have a substituent A linear or branched alkenyl group having 2 to 10 carbon atoms, n is 0 or 1, and Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine.

A seventh aspect of the present invention is a method for forming a photoresist pattern, which comprises the step of forming a photoresist film on a support by using the photoresist composition of the sixth aspect, and the photoresist film is formed. a step of exposing, and a step of alkali developing the aforementioned photoresist film to form a photoresist pattern.

In the present specification and the scope of the patent application, "aliphatic" is a relative concept with respect to aromatics, and is defined as a group or a compound having no aromaticity.

The "aliphatic cyclic group" means a monocyclic group or a polycyclic group which does not have an aromatic group.

The "alkyl group" is a one which contains a linear, branched, and cyclic monovalent saturated hydrocarbon group, unless otherwise specified.

The "alkylene group" is preferably a linear, branched or cyclic divalent saturated hydrocarbon group unless otherwise specified.

"Lower alkyl" means an alkyl group having 1 to 5 carbon atoms.

"Structural unit" means the monomer unit (monomer unit) constituting the resin component (polymer).

"Exposure" is a concept that includes the full illumination of radiation.

The present invention provides a novel compound suitable as an acid generator for a photoresist composition and a method for producing the same, and a compound suitable as a precursor of the compound and a method for producing the same, an acid generator, a photoresist composition and a photoresist pattern The method of formation.

Compound (B1)

The compound (B1) of the first aspect of the present invention is represented by the above formula (b1-1).

In the formula (b1-1), n1 is 0 or 1. When n1 is 0, the compound (B1) is represented by the following formula (b1-1-1). In the case where n1 is 1, the compound (B1) is represented by the following formula (b1-1-2).

Wherein R ¹ , R ³ , A, R ² , n, and Y ¹ are the same as those of R ¹ , R ³ , A, R ² , n, and Y ¹ in the formula (b1-1), respectively.

The aryl group of R ¹ is not particularly limited, and examples thereof include an aryl group having 6 to 20 carbon atoms. The aryl group is preferably an aryl group having 6 to 10 carbon atoms from the viewpoint of inexpensive synthesis, and specifically, for example, a phenyl group or a naphthyl group.

The aryl group may have a substituent. Here, the aryl group has a substituent, and a part or all of a hydrogen atom which is an unsubstituted aryl group is partially substituted by a substituent (a group or an atom other than a hydrogen atom).

The aryl group may have a substituent such as an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group or the like.

The alkyl group as a substituent of the above aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.

The alkoxy group as a substituent of the above aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, a tert-butoxy group or the like. .

The alkoxy group as a substituent of the above aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, and an n-butoxy group. Base, tert-butoxy is preferred, and methoxy and ethoxy are preferred. .

The halogen atom as a substituent of the above aryl group, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

The halogenated alkyl group as a substituent of the above aryl group, for example, a part or all of a hydrogen atom of the above alkyl group is substituted by the above halogen atom.

The alkyl group of R ¹ is not particularly limited, and examples thereof include a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms. From the viewpoint of excellent resolution, the carbon number is 1 to 5. Specifically, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an anthracenyl group, an anthracenyl group and the like. For a substance having excellent resolution and being inexpensively synthesized, for example, a methyl group or the like.

The alkyl group may have a substituent. Wherein the alkyl group has a substituent means that a part or the whole of one of the hydrogen atoms of the unsubstituted alkyl group is substituted by a substituent (a group or an atom other than a hydrogen atom).

The alkyl group may have a substituent such as an alkoxy group, a halogen atom, a hydroxyl group or the like. The alkoxy group and the halogen atom are the same as those of the alkoxy group and the halogen atom exemplified as the substituent which the aryl group may have.

In the present invention, R ¹ is preferably an aryl group which may have a substituent, and a phenyl group or a naphthyl group which may have a substituent is more preferable, and a phenyl group which may have a substituent is preferable.

The alkyl group of R ³ is not particularly limited, and for example, it may be the same as the alkyl group of the above R ¹ .

In the present invention, R ³ is preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.

In the case where n1 is 1, R ¹ and R ³ in the formula may be bonded to each other, and a carbon atom bonded to the R ¹ and a carbon atom bonded to R ³ simultaneously form a ring of a 3 to 7 member ring structure. The ring is preferably constructed with a 5 to 7 member ring and is preferably constructed with a 5 or 6 member ring.

A is a divalent group which forms a ring of a 3 to 7 member ring structure simultaneously with the sulfur atom bonded to the A, and the ring may have a substituent.

In A, the ring is preferably a 5-7 member ring structure, and a 5 or 6 member ring structure is preferred.

The above ring may have a substituent, for example, the same as those recited in the substituent which the aryl group of the above R ¹ may have.

The cationic portion of the compound (B1) is particularly preferably a cationic moiety represented by the following formula (b1'-1) or (b1'-2).

In the formula, R ⁸ and R ⁹ are each independently a phenyl group, a naphthyl group or an alkyl group having 1 to 5 carbon atoms which may have a substituent. The alkyl group is preferably a methyl group.

a is an integer from 1 to 3, and 1 or 2 is the best.

In the formula (b1-1), the aromatic group of R ² may be a hydrocarbon group formed only of a carbon atom and a hydrogen atom, or a hetero atom-containing group containing a carbon atom, a hydrogen atom or a hetero atom other than the same. . Specifically, for example, a ring of an aromatic hydrocarbon such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthyl group or a phenanthryl group removes an aryl group of one hydrogen atom. And a heteroaryl group obtained by substituting a part of a carbon atom of the ring of the aryl group with a hetero atom such as an oxygen atom, a sulfur atom or a nitrogen atom. For example, an aralkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group or a 2-naphthylethyl group.

The carbon number of the alkyl chain in the aralkyl group is preferably 1 to 4, more preferably 1 to 2, and most preferably 1 is used.

The aromatic group of R ² may have a substituent. The substituent is, for example, the same as those exemplified for the substituent which the aryl group of the above R ¹ may have.

In R ² , a linear alkyl group having 1 to 10 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group or a fluorenyl group. Among them, methyl is preferred.

a branched alkyl group having 1 to 10 carbon atoms, for example, 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, and the like.

The alkyl group of R ² may have a substituent. The substituent is, for example, the same as those exemplified for the substituent which the alkyl group of the above R ¹ may have.

The linear or branched alkenyl group having 2 to 10 carbon atoms of R ² is preferably 2 to 5 carbon atoms, more preferably 2 to 4 carbon atoms, and most preferably 3 carbon atoms. Specifically, for example, a vinyl group, an allyl group (allyl), a butenyl group, a 1-methylpropenyl group, a 2-methylpropenyl group or the like is preferable, and a propylene group is particularly preferable.

The alkenyl group of R ² may have a substituent. The substituent is, for example, the same as those exemplified for the substituent which the alkyl group of the above R ¹ may have.

Here, in R ² , "may have a substituent" means an aromatic hydrocarbon group, a linear or branched alkyl group, or a linear or branched alkenyl group, and a part of a hydrogen atom. Or all may be replaced by a substituent (an atom other than a hydrogen atom or a group).

In R ² , the number of the substituents may be one or two or more.

n can be 0, or 1 can also be.

Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine.

a alkylene group of Y ¹ which may be substituted by fluorine and having a carbon number of 1 to 4, such as -CF ₂ -, -CF ₂ CF ₂ -, -CF ₂ CF ₂ CF ₂ -, -CF(CF ₃ )CF ₂ -, -CF(CF ₂ CF ₃ )-, -C(CF ₃ ) ₂ -, -CF ₂ CF ₂ CF ₂ CF ₂ -, -CF(CF ₃ )CF ₂ CF ₂ -, -CF ₂ CF(CF ₃ ) CF ₂ -, -CF(CF ₃ )CF(CF ₃ )-, -C(CF ₃ ) ₂ CF ₂ -, -CF(CF ₂ CF ₃ )CF ₂ -, -CF(CF ₂ CF ₂ CF ₃ ) -, -C(CF ₃ )(CF ₂ CF ₃ )-; -CHF-, CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ -, -CH ₂ CF ₂ CF ₂ -, -CH(CF ₃ ) CH ₂ -, -CH(CF ₂ CF ₃ )-, -C(CH ₃ )(CF ₃ )-, -CH ₂ CH ₂ CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ CF ₂ -, -CH (CF ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CF ₃ )CH ₂ -, -CH(CF ₃ )CH(CF ₃ )-, -C(CF ₃ ) ₂ CH ₂ -; -CH ₂ - , -CH ₂ CH ₂ -, -CH ₂ CH ₂ CH ₂ -, -CH(CH ₃ )CH ₂ -, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -CH ₂ CH ₂ CH ₂ CH ₂ -, -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) _{2 CH 2 -, - CH (} CH 2 CH 3) CH 2 -, _{CH (CH 2 CH 2 CH 3} ) -, - C (CH 3) (CH 2 CH 3) - and the like.

Further, Y ¹ is preferably an alkylene group (fluorinated alkyl group) having 1 to 4 carbon atoms which may be substituted by fluorine, particularly a fluorinated alkylene group which is bonded to a carbon atom adjacent to a sulfur atom. The base is good. The above-mentioned fluorinated alkyl group, for example, -CF ₂ -, -CF ₂ CF ₂ -, -CF ₂ CF ₂ CF ₂ , -CF(CF ₃ )CF ₂ -, -CF ₂ CF ₂ CF ₂ CF ₂ - , CF(CF ₃ )CF ₂ CF ₂ -, -CF ₂ CF(CF ₃ )CF ₂ -, -CF(CF ₃ )CF(CF ₃ )-, -C(CF ₃ ) ₂ CF ₂ -, -CF( CF ₂ CF ₃ )CF ₂ -; -CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ -, -CH ₂ CF ₂ CF ₂ -; -CH ₂ CH ₂ CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ CF ₂ -, -CH ₂ CF ₂ CF ₂ CF ₂ -, and the like.

Further, -CF ₂ CF ₂ -, -CF ₂ CF ₂ CF ₂ -, or CH ₂ CF ₂ CF ₂ - is preferred, and -CF ₂ CF ₂ - or -CF ₂ CF ₂ CF ₂ - is more preferred. It is most preferred to use -CF ₂ CF ₂ -.

In the present invention, the anion portion of the compound (B1) is preferably an anion portion represented by the following formula (b1"-1).

[wherein Y ¹ is the same as defined above, R ⁵³ is an alkenyl group or an aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a linear or branched alkyl group having 1 to 5 carbon atoms] .

R ^{53 is} preferably a vinyl group, a phenyl group or a naphthyl group, and more preferably a vinyl group or a naphthyl group.

R ⁵⁴ is preferably a linear alkyl group having 1 to 5 carbon atoms, and the methyl group is most preferred.

The compound (B1) of the present invention is formed by the cation portion represented by the above formula (b1'-1) or (b1'-2) and the anion portion represented by the above formula (b1"-1). The compound is preferred.

<Method for Producing Compound (B1)>

The method for producing the compound (B1) of the present invention is not particularly limited, and a known method for producing a phosphonium salt can be used.

For example, a compound (b0-1) represented by the following formula (b0-1) and a compound (b0-2) represented by the following formula (b0-2) can be reacted to obtain a compound (B1). .

[wherein, R ² , n, Y ¹ , A, R ³ , n1, and R ¹ are each independently of R ² , n, Y ¹ , A, R ³ , n1, and R ¹ in the formula (b1-1). The same content. M ⁺ is an alkali metal ion and Xh ^- is a halogen ion.

The metal ion of M ^{+ is} , for example, sodium ion, lithium ion, potassium ion or the like, and sodium ion or lithium ion is preferred.

Xh ^- a halogen ion, such as a chloride ion, a bromide ion, an iodide ion, etc., preferably a chloride ion or a bromide ion.

The compound (b0-1) and the compound (b0-2) can be reacted, for example, by contacting the above compound in a solvent such as water or dichloromethane.

The method for producing the compound (b0-1) is not particularly limited. For example, a compound represented by the following formula (b0-1-11) is dissolved in a solvent such as tetrahydrofuran or water with sodium hydroxide or hydroxide. The reaction is carried out in an aqueous solution of an alkali metal hydroxide such as lithium to form a compound represented by the following formula (b0-1-12), and the compound is then dissolved in an organic solvent such as benzene or dichloroethane. Dehydration condensation with an alcohol represented by the following formula (b0-1-13) in the presence of an acidic catalyst to obtain a compound of the above formula (b0-1) wherein n is 1 (hereinafter referred to as a compound represented by the formula (b0-1-01)).

[Wherein, R ²¹ is alkyl of 1 to ^5, Y ^1, M ^+, R ² respectively of the formula ^{(b0-1) Y 1, M +} , R 2 is the same as the contents, Xh ^- is It is the same as Xh ^- in the formula (b0-2).

Further, for example, silver fluoride, a compound represented by the following formula (b0-1-01), and a compound represented by the following formula (b0-1-02), in anhydrous diglyme, etc. The reaction is carried out in an organic solvent to obtain a compound represented by the following formula (b0-1-03), which is then dissolved in an organic solvent such as tetrahydrofuran, acetone or methyl ethyl ketone with sodium hydroxide or hydrogen. An alkali metal hydroxide such as lithium oxide is reacted to obtain a compound of the above formula (b0-1) wherein n is 0 (a compound represented by the following formula (b0-1-0)).

^[Wherein, Y ^1, M ^+, R ² respectively of the formula ^{(b0-1) Y 1, M +} , R 2 is the same as the contents, Xh ^- with the formula (b0-2) in the Xh ^- is The same content].

The method for producing the compound (b0-2) is not particularly limited. For example, a sulfur atom of a compound represented by the following formula (b0-2-1) can be introduced into -[CH(R ³ ) by a known method. ) -CO] is obtained by the method represented by _{n1 -} R ¹ .

Specifically, for example, when the case where n1 is 0 is exemplified, the compound represented by the following formula (b0-2-1) is oxidized, and the -S- moiety in the compound is taken as -S(=O). In the presence of a catalyst such as aluminum chloride, it is reacted with an aromatic hydrocarbon such as benzene or an alkane such as methane to obtain a compound of the above formula (b0-2) wherein n1 is 0. In the case where n1 is 1, for example, a commercially available bromide or the like can be used.

[In the formula, the A system is the same as the above content].

When n1 is 0, that is, the compound (B1) is a compound represented by the above formula (b-1-1) (hereinafter, also referred to as a compound (B1-1)), and the compound (B1-1) The production method is preferably a method for producing the compound (B1-1) of the present invention to be described later.

Method for producing compound (B1-1)

The method for producing the compound (B1-1) of the second aspect of the present invention (hereinafter also referred to as the production method (1)) includes the following general formula (I) The compound (hereinafter also referred to as the compound (I)) and the compound represented by the following formula (II) (hereinafter also referred to as the compound (II)) are reacted with a copper catalyst to produce The step of the compound (B1-1) represented by the following formula (b1-1-1) is obtained.

When these steps are carried out, R ¹ in the compound (I) can be introduced into the sulfur atom of the compound (II) to form a cerium ion, and the cerium ion is formed into a salt with the anion portion of the compound (I) to prepare a compound ( B1-1).

Wherein A is a divalent group which can form a ring of a 3 to 7 member ring structure simultaneously with the sulfur atom bonded to the A, the ring may have a substituent, and R ² is an aromatic hydrocarbon group which may have a substituent a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or a linear or branched alkenyl group having 2 to 10 carbon atoms which may have a substituent, n is 0. Or 1, Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine, and R ¹ is an aryl group or an alkyl group which may have a substituent independently.

In the formula, A, R ² , n, Y ¹ and R ¹ are each independently, and are the same as those of A, R ² , n, Y ¹ and R ¹ in the above formula (b-1).

The compound (I) used therein is a novel compound. The compound (I), for example, can be produced by the production method of the compound (I) described later.

As the compound (Il), a commercially available article or a synthetic product can be used.

The copper catalyst is preferably a copper catalyst which is a divalent, and, for example, a compound represented by the following formula (III) (hereinafter also referred to as a compound (III)).

[wherein R ⁶ is an aryl group which may have a substituent].

In the formula, the aryl group which may have a substituent of R ⁶ is, for example, the same as those exemplified for the aryl group which may have a substituent of the above R ¹ .

The compound (III), specifically, for example, copper (II) benzoate or the like.

As the compound (III), commercially available articles can be used.

The method of reacting the compound (I) with the compound (II) and the copper catalyst is not particularly limited. For example, the compound (I) and the compound (II) can be reacted with a copper catalyst in a reaction solvent. Reaction and other methods.

The reaction solvent may be any solvent which can dissolve the raw material, and specifically, for example, chlorobenzene or toluene.

The reaction temperature is preferably 50 to 150 ° C, more preferably 90 to 120 ° C.

The reaction time varies depending on the reactivity of the compound (I) and the compound (II), the reaction temperature, etc., and is usually preferably from 10 to 180 minutes, more preferably from 30 to 90 minutes.

The amount of the compound (II) used is relative to the compound (I). Approximately 0.5 to 3 mole equivalents are preferred, and 0.9 to 1.5 mole equivalents are preferred.

The amount of the copper catalyst to be used is preferably from about 0.01 to 0.5 mol equivalents, more preferably from 0.02 to 0.1 mol equivalents, based on the compound (I).

According to the structure of the compound (B1-1) obtained in the above step, ¹ H-nuclear magnetic resonance (NMR) spectroscopy, ¹³ C-NMR spectroscopy, ¹⁹ F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass analysis can be used. General organic analysis methods such as (MS) method, elemental analysis method, and X-ray crystal diffraction method are confirmed.

Compound (I)

The compound (I) of the third aspect of the present invention is represented by the above formula (I).

In the formula (I), R ² , n, Y ¹ and R ¹ are the same as those of R ² , n, Y ¹ and R ¹ in the above formula (b1-1).

The compound (I) can be used as a precursor of the above compound (B1-1), and is also suitable for the production method (1) of the above compound (B1-1).

Further, since the compound (I) itself can be used as an acid generator, it can be added to the photoresist composition as an acid generator.

Method for producing compound (I)

The method for producing the compound (I) of the fourth aspect of the present invention includes, for example, a compound represented by the following formula (I-1) (hereinafter also referred to as the compound (I-1)), and the following The compound represented by the formula (I-2) (hereinafter, also referred to as the compound (I-2)) is reacted to obtain a compound (I). ) The steps.

[wherein R ² is an aromatic hydrocarbon group which may have a substituent, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or a carbon number of 2 to 10 which may have a substituent a linear or branched alkenyl group, n is 0 or 1, Y ¹ is a C 1 to 4 alkyl group which may be substituted by fluorine, M ⁺ is an alkali metal ion, and R ¹ is independently An aryl group or an alkyl group having a substituent, and R ⁷ is an alkyl group or a fluorinated alkyl group].

In the formula, R ² , n, Y ¹ and R ¹ are the same as those of R ² , n, Y ¹ and R ¹ in the above formula (b1-1).

M ⁺ alkali metal ions, such as sodium ions, lithium ions, potassium ions, and the like.

The alkyl group or the fluorinated alkyl group of R ⁷ may be any of a linear chain, a branched chain or a cyclic chain.

The linear or branched alkyl group preferably has a carbon number of 1 to 10, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.

The alkyl group having a ring number of 4 to 15 is preferably a carbon number of 4 to 10, more preferably a carbon number of 6 to 10.

The fluorinated alkyl group is, for example, a group in which a part or all of a hydrogen atom of the alkyl group is substituted by a fluorine atom.

R ^{7 is} preferably an alkyl group, preferably a linear alkyl group, and most preferably a methyl group.

The compound (I-1) can be synthesized, for example, by the same method as the method for producing the above compound (b0-1).

As the compound (I-2), commercially available articles can be used.

The compound (I-1) and the compound (I-2) can be reacted by, for example, contacting them with a solvent such as water or dichloromethane.

According to the structure of the compound obtained in the above step, ¹ H-nuclear magnetic resonance (NMR) spectroscopy, ¹³ C-NMR spectroscopy, ¹⁹ F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass spectrometry (MS), General organic analysis methods such as elemental analysis and X-ray crystal diffraction are confirmed.

Acid generator

The acid generator of the fifth aspect of the present invention is formed of the compound (B1) of the first aspect described above.

The acid generator is an acid generator for a chemically amplified photoresist composition, and can be used, for example, as the acid generator component (B) of the photoresist composition of the sixth aspect of the invention to be described later.

Photoresist composition

The photoresist composition of the sixth aspect of the present invention is a substrate component (A) containing a change in solubility of an alkali developer via an action of an acid ( Next, also referred to as (A) component), and an acid generator component (B) (hereinafter, also referred to as (B) component) which generates an acid by exposure, and the component (B) contains the above formula (b1- 1) An acid generator (B1) formed by the compound represented.

When the photoresist film formed by the photoresist composition is selectively exposed during the formation of the photoresist pattern, acid can be generated in the component (B), and the solubility of the component (A) to the alkali developer can be made via the acid. Make a difference. As a result, the solubility of the exposed portion of the resist film to the alkali developing solution can be changed, and the unexposed portion does not change the solubility of the alkali developing solution. In the case where the exposed portion is dissolved and removed, in the case of a negative type, the unexposed portion is dissolved and removed to form a photoresist pattern.

The photoresist composition of the present invention may be a negative photoresist composition or a positive photoresist composition.

<(A) ingredient>

In the component (A), the organic compound used as the substrate component for the chemically amplified photoresist can be used singly or in combination of two or more kinds.

Here, the "substrate component" means an organic compound having a film forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film formation ability can be improved, and a photoresist pattern of a nanometer degree can be easily formed.

The above organic compound having a molecular weight of 500 or more can be roughly classified into An organic compound having a molecular weight of 500 or more, a low molecular weight of less than 2,000 (hereinafter also referred to as a low molecular compound), and a high molecular weight resin (polymer material) having a molecular weight of 2,000 or more. The aforementioned low molecular compound is usually a non-polymer. In the case of a resin (polymer or copolymer), the "molecular weight" is a mass average molecular weight in terms of polystyrene using GPC (gel permeation chromatography). Hereinafter, the term "resin" alone means a resin having a molecular weight of 2,000 or more.

As the component (A), a resin which changes the solubility of the alkali by the action of an acid or a low molecular material which changes the solubility of the alkali by the action of an acid can be used.

When the photoresist composition of the present invention is a negative photoresist composition, the component (A) may be a substrate component which is soluble in an alkali developer, or a crosslinking agent may be added to the negative photoresist composition.

When the negative photoresist composition generates an acid by the (B) component by exposure, cross-linking occurs between the substrate component and the crosslinking agent by the action of the acid, and the solubility is poorly soluble in the alkali developing solution. Therefore, in the formation of the photoresist pattern, when the photoresist film coated on the substrate is selectively exposed by the negative photoresist composition, the exposed portion can be converted to be insoluble to the alkali developer. The unexposed portion is formed into a photoresist pattern by alkali development without being changed to be soluble in the alkali developing solution.

The component (A) of the negative resist composition is usually a resin which is soluble in an alkali developer (hereinafter also referred to as an alkali-soluble resin).

An alkali-soluble resin having at least one selected from the group consisting of α-(hydroxyalkyl)acrylic acid or lower alkyl ester of α-(hydroxyalkyl)acrylic acid The resin of the derived unit can form a good photoresist pattern with less swelling, and is preferred. Further, α-(hydroxyalkyl)acrylic acid is an acrylic acid obtained by bonding a hydrogen atom bonded to a carbon atom at the α position of a carboxyl group, and a hydroxyalkyl group is bonded to the carbon atom at the α position (preferably, carbon number 1~) The hydroxyalkyl group of 5 is intended to have one or both of the bonded alpha-hydroxyalkylacrylic acids.

The crosslinking agent, for example, when an amine-based crosslinking agent having a methylol group or an alkoxymethyl group such as glycoluril is usually used, a good photoresist pattern having less swelling is formed, and is preferable. The amount of the crosslinking agent added is preferably from 1 to 50 parts by mass based on 100 parts by mass of the alkali-soluble resin.

When the photoresist composition of the present invention is a positive-type photoresist composition, the component (A) can be used as a substrate component which increases the solubility in an alkali developer by the action of an acid. In other words, the component (A) is poorly soluble in the alkali developer before exposure, and when the component (B) is acidified by exposure, the solubility in the alkali developer is increased by the action of the acid. When the resist pattern is formed, when the resist film obtained by applying the positive resist composition on the substrate is selectively exposed, the exposed portion is converted from soluble to soluble in the alkali developing solution, and the unexposed portion is formed. In the state in which the alkali is poorly soluble, a photoresist pattern can be formed by alkali development.

In the photoresist composition of the present invention, the component (A) is preferably a component of the substrate which increases the solubility in the alkali developer via the action of an acid. That is, the photoresist composition of the present invention is preferably a positive photoresist composition.

The component (A) may be a resin component (A1) (hereinafter, also referred to as (A1) component) which increases solubility in an alkali developer via an action of an acid, or may be increased by an action of an acid. Low solubility in alkaline developer The molecular compound (A2) (hereinafter also referred to as (A2) component) may also be used, or such a mixture may also be used.

[(A1) ingredients]

The component (A1) is usually a resin component (base resin) which is used as a substrate component for a chemically amplified photoresist, and may be used alone or in combination of two or more.

In the present invention, the component (A1) is preferably a structural unit derived from an acrylate.

In the present specification and the scope of the patent application, "the structural unit derived from acrylate" means the structural unit formed by the cracking of the ethylenic double bond of the acrylate.

The "acrylate" refers to a concept in which a carbon atom in the alpha position is a compound in which a carbon atom bonded to a hydrogen atom is bonded to a carbon atom at the alpha position (atom or a group other than a hydrogen atom). A substituent such as a lower alkyl group, a halogenated lower alkyl group or the like.

Further, the α-position (carbon atom at the α-position) of the structural unit derived from the acrylate means a carbon atom bonded to the carbonyl group unless otherwise specified.

In the acrylate, a lower alkyl group of the substituent at the α-position, specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isoprene group A lower linear or branched alkyl group such as a benzyl group or a neopentyl group.

Further, a halogenated lower alkyl group, specifically, a part or all of a hydrogen atom in the above "lower alkyl group of the substituent of the α-position" is substituted by a halogen atom The basis of the obtained. The halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

In the present invention, the α-position of the acrylate is preferably a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and more preferably a hydrogen atom, a lower alkyl group or a fluorinated lower alkyl group. It is easy to obtain a viewpoint such as a hydrogen atom or a methyl group.

The component (A1) is preferably a structural unit (a1) derived from an acrylate having an acid-dissociable dissolution inhibiting group.

Further, the component (A1) is preferably a structural unit (a2) derived from an acrylate having a cyclic group containing a lactone, in addition to the structural unit (a1).

The component (A1) is preferably a structural unit (a3) derived from an acrylate having a polar group-containing aliphatic hydrocarbon group, in addition to the structural unit (a1) or structural units (a1) and (a2).

. Structural unit (a1)

The acid dissociable dissolution inhibiting group in the structural unit (a1) is such that, as long as the component (A1) has an alkali-insoluble alkali dissolution inhibiting property before dissociation, the (A1) component is increased after dissociation by acid. The base of the solubility of the alkali developer may be used, and an acid dissociable dissolution inhibiting group which has been proposed as a base resin for a chemically amplified resist composition can be used. In general, for example, a carboxyl group or a chain-like tertiary alkyl ester group or a acetal acid dissociable dissolution inhibiting group such as an alkoxyalkyl group can be formed with a carboxyl group in (meth)acrylic acid.

Here, the "trialkyl ester", for example, a hydrogen atom of a carboxyl group is substituted with a chain or a cyclic alkyl group to form an ester, and an oxygen atom at the terminal of the carbonyloxy group (-C(O)-O-) is bonded. A structure obtained by the tertiary carbon atom of the above-mentioned chain or cyclic alkyl group. In the above tertiary alkyl ester, the bond between the oxygen atom and the tertiary carbon atom can be interrupted by the action of an acid.

Further, the aforementioned chain or cyclic alkyl group may have a substituent.

Hereinafter, the acid dissociable group formed by a carboxyl group and a tertiary alkyl ester is conveniently referred to as a "triester alkyl ester type acid dissociable dissolution inhibiting group".

The tertiary alkyl ester type acid dissociable dissolution inhibiting group is, for example, an aliphatic branched acid dissociable dissolution inhibiting group, an acid dissociable dissolution inhibiting group containing an aliphatic cyclic group, and the like.

"Aliphatic branched" means a branched structure having no aromaticity. The structure of the "aliphatic branched acid dissociable dissolution inhibiting group" is not limited to a group (hydrocarbon group) formed of carbon and hydrogen, but a hydrocarbon group is preferred. Further, the "hydrocarbon group" may be either saturated or unsaturated, and it is generally preferred to saturate.

The aliphatic branched acid dissociable dissolution inhibiting group is preferably a tertiary alkyl group having 4 to 8 carbon atoms, and specifically, for example, tert-butyl group, tert-pentyl group, tert-heptyl group or the like.

The "aliphatic cyclic group" means a monocyclic or polycyclic group having no aromaticity.

The "aliphatic cyclic group" in the structural unit (a1) may have a substituent or may not have a substituent. Substituents such as low carbon number 1 to 5 An alkyl group, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted by a fluorine atom, an oxygen atom (=O), or the like.

The basic ring structure in which the substituent is removed in the "aliphatic cyclic group" is not limited to a group (hydrocarbon group) formed of carbon and hydrogen, but a hydrocarbon group is preferred. Further, the "hydrocarbon group" may be either saturated or unsaturated, and generally it is preferably saturated. The "aliphatic cyclic group" is preferably a polycyclic group.

Specific examples of the aliphatic cyclic group, for example, may be substituted by a lower alkyl group, a fluorine atom or a fluorinated alkyl group, or may be unsubstituted, or may be a monocyclic alkane, a bicycloalkane, a tricycloalkane or a tetra. A group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as a cycloalkane. More specifically, for example, a monocyclic alkane such as cyclopentane or cyclohexane or a polycyclic alkane such as adamantane, norbornane, isopentane, tricyclodecane or tetracyclododecane is removed. A group obtained by one or more hydrogen atoms.

An acid dissociable dissolution inhibiting group containing an aliphatic cyclic group, for example, a group having a tertiary carbon atom on a ring skeleton of a cyclic alkyl group, and the like, specifically, for example, 2-methyl-2-adamantyl group, Or 2-ethyl-2-adamantyl and the like. Or, for example, in the structural unit represented by the following general formula (a1"-1) to (a1"-6), it is bonded to a group of an oxygen atom of a carbonyloxy group (-C(O)-O-), and has a diamond An aliphatic cyclic group such as an alkyl group, a cyclohexyl group, a cyclopentyl group, a norbornyl group, a tricyclodecyl group, a tetracyclododecyl group, or the like, and a branched chain having a tertiary carbon atom bonded thereto Alkyl group and the like.

Wherein R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; and R ¹⁵ and R ¹⁶ are an alkyl group (may be linear or branched, preferably having a carbon number of 1 to 5). ].

In the formula (a1"-1)~(a1"-6), the lower alkyl group of the R or the halogenated lower alkyl group is, for example, a lower alkyl group or a halogenated lower alkyl group which may be bonded to the α-position of the acrylate. The same content.

The "acetal type acid dissociable dissolution inhibiting group" is generally an oxygen atom bonded to a hydrogen atom at the terminal of an alkali-soluble group such as a carboxyl group or a hydroxyl group. Therefore, when an acid is generated by exposure, the bond between the acetal type acid dissociable dissolution inhibiting group and the oxygen atom to which the acetal type acid dissociable dissolution inhibiting group is bonded is cut by the action of the acid.

The acetal type acid dissociable dissolution inhibiting group is, for example, a group represented by the following formula (p1).

[wherein, R ^{1 '} and R ^{2 '} are each independently a hydrogen atom or a lower alkyl group, n is an integer of 0 to 3, and Y is a lower alkyl group or an aliphatic cyclic group].

In the above formula, n is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.

The lower alkyl group of R ^{1 '} and R ^{2 '} is, for example, the same as the lower alkyl group of the above R, and preferably a methyl group or an ethyl group, and a methyl group is most preferable.

In the present invention, it is preferred that at least one of R ^{1 '} and R ^2' is a hydrogen atom. In other words, the acid dissociable dissolution inhibiting group (p1) is preferably a group represented by the following formula (p1-1).

[In the formula, R ^{1 '} , n, and Y are the same as those described above].

The lower alkyl group of Y is, for example, the same as the lower alkyl group of the above R.

The aliphatic ring group of Y may be appropriately selected from among the monocyclic or polycyclic aliphatic ring groups which have been proposed many times in the conventional ArF photoresist, for example, and the above-mentioned "aliphatic ring type". The base is the same content.

Further, an acetal type acid dissociable dissolution inhibiting group, for example, the following formula (p2) ) the base shown.

[wherein, R ¹⁷ and R ¹⁸ are each independently a linear or branched alkyl group or a hydrogen atom, and R ¹⁹ is a linear, branched or cyclic alkyl group, or each of R ¹⁷ and R ¹⁹ independently alkylene of straight or branched chain, R ¹⁷ and R-terminal end of the bond of the junction ¹⁹ may form a ring].

In R ¹⁷ and R ¹⁸ , the alkyl group preferably has 1 to 15 carbon atoms, and may be linear or branched, preferably ethyl or methyl, and methyl.

In particular, any of R ¹⁷ and R ¹⁸ is a hydrogen atom, and the other is preferably a methyl group.

When R ¹⁹ is a linear, branched or cyclic alkyl group, the number of carbon atoms is preferably from 1 to 15, and it may be any of a linear chain, a branched chain or a cyclic chain.

When R ¹⁹ is linear or branched, the carbon number is preferably from 1 to 5, more preferably ethyl or methyl, and most preferably ethyl.

When R ¹⁹ is a ring, it is preferably 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, it may be substituted by a fluorine atom or a fluorinated alkyl group, or may be removed by a polycyclic alkane such as a monocyclic alkane, a bicycloalkane, a tricycloalkane or a tetracycloalkane which is not substituted. More than one hydrogen atom or the like. Specifically, for example, a monocyclic alkane such as cyclopentane or cyclohexane or one or more polycyclic alkane such as adamantane, norbornane, isopentane, tricyclodecane or tetracyclododecane is removed. The base of a hydrogen atom, etc. Among them, the base obtained by removing one or more hydrogen atoms from adamantane is preferred.

Further, in the above formula, R ¹⁷ and R ¹⁹ are each independently a linear or branched alkyl group (preferably an alkyl group having 1 to 5 carbon atoms), and the end of R ¹⁹ may be bonded to R ¹⁷ The end bond can also be used.

At this time, R ¹⁷ and R ¹⁹ , and an oxygen atom bonded to R ¹⁹ form a cyclic group with the oxygen atom bonded to the carbon atom bonded to R ¹⁷ . The ring base is preferably a 4 to 7 ring, and a 4 to 6 ring is preferred. Specific examples of the cyclic group include, for example, a tetrahydropyranyl group, a tetrahydrofuranyl group and the like.

The structural unit (a1) is one selected from the group consisting of the structural unit represented by the following general formula (a1-0-1) and the structural unit represented by the following general formula (a1-0-2). The above is better.

[In the formula, R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; and X ¹ is an acid dissociable dissolution inhibiting group].

Wherein R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; X ² is an acid dissociable dissolution inhibiting group; and Y ² is an alkylene group or an aliphatic cyclic group.

In the formula (a1-0-1), the lower alkyl group or the halogenated lower alkyl group of R is the same as the above-mentioned halogen atom which may be bonded to the α-position of the acrylate, lower alkyl group or halogenated lower alkyl group. .

X ¹ is not particularly limited as long as it is an acid dissociable dissolution inhibiting group, and may be, for example, a tertiary alkyl ester type acid dissociable dissolution inhibiting group or an acetal type acid dissociating dissolution inhibiting group, and a trisalkane. The ester-type acid dissociable dissolution inhibiting group is preferred.

In the formula (a1-0-2), R has the same meaning as described above.

X ² is the same as X ¹ in the formula (a1-0-1).

Y ^{2 is} preferably an alkylene group having 1 to 10 carbon atoms or a divalent aliphatic cyclic group. When the aliphatic cyclic group is used, it may be used, for example, in addition to a group having two or more hydrogen atoms removed. The description of "aliphatic ring-based" is the same.

When Y ² is an alkylene group having 1 to 10 carbon atoms, the carbon number is preferably 1 to 6 and the carbon number is preferably 1 to 4, and the carbon number is preferably 1 to 3.

When Y ² is a divalent aliphatic cyclic group, two or more hydrogen atoms are removed by cyclopentane, cyclohexane, norbornane, isobornane, adamantane, tricyclodecane or tetracyclododecane. The basis of the obtained is particularly good.

In the structural unit (a1), more specifically, for example, the structural unit represented by the following general formulae (a1-1) to (a1-4).

[In the above formulas, X 'is a three alkyl ester-type acid dissociable, dissolution inhibiting group; Y is a lower alkyl group having a carbon number of 1 to 5, or an aliphatic cyclic group; n is an integer of 0 to 3; Y ² Is an alkyl group or an aliphatic cyclic group; R has the same meaning as above; R ^{1 '} and R ^{2 '} are each independently a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms].

In the formula, X' is the same as the tertiary alkyl ester type acid dissociable dissolution inhibiting group exemplified in the above X ¹ .

^{R 1 ', R 2',} n, Y lines were above the "acetal-type acid dissociable, dissolution inhibiting group" exemplified in the description of general formula (p1) in the ^{R 1 ', R 2',} n, Y is the same content.

Y ^{2 is} , for example, the same as Y ² in the above formula (a1-0-2).

The following are specific examples of the structural unit represented by the above general formulae (a1-1) to (a1-4).

In the above formula, the structural unit represented by the formula (a1-1) is preferably used, specifically, the formula (a1-1-1) to (a1-1-6) and the formula (a1-1-) are used. 35) At least one selected from the group consisting of (a1-1-41) is more preferable.

Further, the structural unit (a1) is, in particular, a unit represented by the following general formula (a1-1-01) including structural units of the formulae (a1-1-1) to (a1-1-4), or an inclusion formula. The following general formula (a1-1-02) of the structural unit of (a1-1-35) to (a1-1-41) is preferred.

Wherein R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and R ¹¹ is a lower alkyl group.

Wherein R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ¹² is a lower alkyl group, and h is an integer of from 1 to 3.

In the formula (a1-1-01), R has the same contents as described above.

The lower alkyl group of R ¹¹ is the same as the lower alkyl group represented by R, and a methyl group or an ethyl group is preferred.

In the general formula (a1-1-02), R has the same contents as described above.

The lower alkyl group of R ¹² is the same as the lower alkyl group represented by the above R, and is preferably a methyl group or an ethyl group, and preferably an ethyl group. h is preferably 1 or 2, and 2 is the best.

The structural unit (a1) may be used alone or in combination of two or more.

In the component (A1), the ratio of the structural unit (a1) is preferably 10 to 80 mol%, more preferably 20 to 70 mol%, based on the entire structural unit constituting the component (A1). 25~50% of the ear is the best. When it is more than the lower limit value, it can be easily formed into a pattern when it is a positive-type photoresist composition, and when it is less than an upper limit, it can balance with another structural unit.

. Structural unit (a2)

In the present invention, the component (A1) is preferably a structural unit (a2) derived from an acrylate having a cyclic group containing a lactone, in addition to the above structural unit (a1).

Wherein the cyclic group containing a lactone is a cyclic group containing one ring (lactone ring) of the -O-C(O)- structure. The lactone ring is counted as a ring unit, and the monocyclic group is only a lactone ring. If it has other ring structures, it is called a polycyclic group regardless of its structure.

The lactone ring group of the structural unit (a2), used as the component (A1) In the case of forming a photoresist film, the adhesion of the photoresist film to the substrate can be effectively improved, and the affinity with the developer containing water can be effectively improved.

Among them, the structural unit (a2) can be used without any limitation.

Specifically, a monocyclic group containing a lactone, for example, a group obtained by removing one hydrogen atom from γ-butyrolactone or the like. Further, the polycyclic group having a lactone is, for example, a group obtained by removing one hydrogen atom from a bicycloalkane having a lactone ring, a tricycloalkane or a tetracycloalkane.

In the example of the structural unit (a2), more specifically, for example, a structural unit represented by the following general formulae (a2-1) to (a2-5).

Wherein R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R' is a hydrogen atom, a lower alkyl group, or an alkoxy group having 1 to 5 carbon atoms, m is an integer of 0 or 1, and A is carbon Number of 1 to 5 alkyl or oxygen atom].

R in the general formulae (a2-1) to (a2-5) has the same content as R in the above structural unit (a1).

The lower alkyl group of R' has the same content as the lower alkyl group of R in the above structural unit (a1).

A alkyl group having a carbon number of 1 to 5, specifically, for example, a methyl group, Ethyl, n-propyl, iso-propyl and the like.

Among the general formulae (a2-1) to (a2-5), R' is preferably a hydrogen atom from the viewpoint of industrial availability.

The following are examples of specific structural units of the above general formulae (a2-1) to (a2-5).

In the structural unit (a2), at least one selected from the group consisting of the structural units represented by the above formulas (a2-1) to (a2-5) is preferred, and the formula (a2-) It is more preferable that at least one selected from the group consisting of the structural units shown in (a2-3) is preferable. Among them, by the chemical formulas (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-2), (a2-3-1), (a2-3 It is preferred that at least one selected from the group consisting of structural units represented by -2) and (a2-3-9) and (a2-3-10).

The structural unit (a2) may be used alone or in combination of two or more.

(A1) component, the proportion of structural units (a2), in pairs ( A1) The total number of structural units of the component is preferably from 5 to 60 mol%, preferably from 10 to 50 mol%, and most preferably from 20 to 50 mol%. When it is more than the lower limit, the effect can be sufficiently obtained when the structural unit (a2) is contained, and when it is equal to or less than the upper limit, a balance with other structural units can be obtained.

. Structural unit (a3)

In the present invention, the component (A1) is derived from the acrylate having the polar group-containing aliphatic hydrocarbon group in addition to the structural unit (a1) or the structural units (a1) and (a2). The structural unit is better.

When the component (A3) contains a structural unit (a3), the hydrophilicity of the component (A1) can be improved, and the affinity with the developer can be improved, and the alkali solubility of the exposed portion can be improved, and the resolution can be expected to be improved.

A polar group such as a hydroxyl group, a cyano group, a carboxyl group, a hydroxyalkyl group in which a part of hydrogen atoms in the alkyl group is substituted by a fluorine atom, and the like, and a hydroxyl group is preferred.

The aliphatic hydrocarbon group is, for example, a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) or a polycyclic aliphatic hydrocarbon group (polycyclic group). The polycyclic group may be, for example, a resin which can be used for a resist composition for an ArF excimer laser, and is appropriately selected from many proposals. The polycyclic group preferably has a carbon number of from 7 to 30.

Further, it is derived from an aliphatic polycyclic acrylate having a hydroxyl group, a cyano group, a carboxyl group, or a hydroxyalkyl group (fluorinated alkyl alcohol) in which a part of a hydrogen atom in the alkyl group is substituted by a fluorine atom. The structural unit is better. The polycyclic group is, for example, removed from a bicycloalkane, a tricycloalkane or a tetracyclic alkane 2 The base obtained by more than one hydrogen atom, and the like. Specifically, for example, a group obtained by removing two or more hydrogen atoms from a polycyclic alkane such as adamantane, norbornane, isopentane, tricyclodecane or tetracyclododecane is used. In the polycyclic group, it is more suitable for industrially to remove two or more hydrogen atoms from adamantane, to remove two or more hydrogen atoms from norbornane, and to remove two or more hydrogen atoms from tetracyclododecane. use.

In the structural unit (a3), when the hydrocarbon group in the aliphatic hydrocarbon group containing a polar group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, the structural unit derived from hydroxyethyl acrylate is preferred. When the hydrocarbon group is a polycyclic group, for example, a structural unit represented by the following formula (a3-1), a structural unit represented by (a3-2), a structural unit represented by (a3-3), or the like is preferable.

[wherein R has the same content as described above, j is an integer from 1 to 3, k is an integer from 1 to 3, t' is an integer from 1 to 3, 1 is an integer from 1 to 5, and s is from 1 to 3. The integer].

In the formula (a3-1), j is preferably 1 or 2, and more preferably 1 is used. In the case where j is 2, the hydroxyl group is bonded to the 3 and 5 positions of the adamantyl group. Better. In the case where j is 1, it is particularly preferable that the hydroxyl group is bonded to the 3 position of the adamantyl group. Among them, it is preferable that j is 1 and it is preferable that the hydroxyl group is bonded to the adamantyl group.

In the formula (a3-2), it is preferred that k is one. It is preferred that the cyano group is bonded to the 5 or 6 position of the norbornyl group.

In the formula (a3-3), it is preferable that t' is one, that 1 is one, and s is one. Preferably, a compound of 2-norbornyl group or 3-norbornyl group is bonded to the terminal of the carboxyl group of the above acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

The structural unit (a3) may be used alone or in combination of two or more.

In the component (A1), the ratio of the structural unit (a3) is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, and more preferably 5 to 50 mol% of the total structural unit constituting the component (A1). 25% Mo is the best. When it is more than the lower limit value, the effect of containing the structural unit (a3) can be sufficiently obtained, and when it is less than the upper limit value, the balance with other structural units can be obtained.

. Structural unit (a4)

The component (A1) may further contain other structural units (a4) other than the above structural units (a1) to (a3) insofar as the effects of the present invention are not impaired.

The structural unit (a4) is not particularly limited as long as it is a structural unit that is not classified into the structural units (a1) to (a3). It can be used for ArF excimer laser, KrF excimer laser (preferably ArF quasi-fraction) A plurality of structural units known in the art for use in photoresists such as sub-lasers.

The structural unit (a4), for example, a structural unit derived from an acrylate having a non-acid dissociable aliphatic polycyclic group is preferable. The polycyclic group is, for example, the same as exemplified in the above structural unit (a1), and can be used for ArF excimer laser or KrF excimer laser (preferably for ArF excimer laser). Most of the structural units previously known for use in the resin composition of the photoresist composition.

In particular, when at least one selected from the group consisting of a tricyclodecylalkyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group is industrially easy to obtain, it is preferred. These polycyclic groups may be substituted by a linear or branched alkyl group having 1 to 5 carbon atoms.

The structural unit (a4) is specifically, for example, a structural unit represented by the following general formulae (a4-1) to (a4-5).

[wherein R has the same content as described above].

When the structural unit (a4) is contained in the component (A1), the ratio of the structural unit (a4) in the component (A1) is 1 to 30% with respect to the total of the structural units constituting the component (A1). Ear% is better, and It is preferably contained in an amount of 10 to 20 mol%.

In the present invention, the component (A1) is preferably a copolymer containing structural units (a1), (a2), and (a3). The copolymer is, for example, a copolymer obtained from structural units (a1), (a2), and (a3), a copolymer obtained by structural units (a1), (a2), (a3), and (a4).

The copolymer is preferably, for example, one having three structural units represented by the following formula (A1-11).

[In the formula, Ra, Rb, and Rc are each independently the same as the above R, and R ¹¹ is a lower alkyl group].

In the formula (A1-11), the lower alkyl group of R ¹¹ is, for example, the same as R ¹¹ in the above formula (a1-1-01), and preferably a methyl group or an ethyl group.

The component (A1) can be obtained by polymerization of a monomer derived from each structural unit, for example, a radical polymerization initiator such as azobisisobutyronitrile (AIBN) by a known radical polymerization.

And, (A1) component, on the occasion of the above-described polymerization, for example, and, at the end introduced and -C (CF ₃ by _{HS-CH 2 -CH 2 -CH 2} -C (CF 3) 2 -OH chain transfer agent, etc. ) ₂ -OH group. Thus, a copolymer having a hydroxyalkyl group in which a part of a hydrogen atom in the alkyl group is substituted with a fluorine atom can be obtained, thereby effectively reducing defects or reducing the effect of LER (Line Edge Roughness).

The mass average molecular weight (Mw) of the component (A1) (the polystyrene equivalent amount of the gel permeation chromatography method) is not particularly limited, and is generally preferably 2,000 to 50,000, more preferably 3,000 to 30,000, and 5,000 to 30,000. ~20,000 is the best. When it is less than the upper limit of the range, sufficient solubility is obtained for the photoresist as a photoresist, and when it is larger than the lower limit of the range, a good dry etching resistance or a resist pattern cross-sectional shape can be obtained.

Further, the degree of dispersion (Mw/Mn) is preferably in the range of 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5. Further, Mn is a number average molecular weight.

[(A2) ingredients]

The component (A2) is preferably an acid dissociable dissolution inhibiting group exemplified in the description of the component (A1) having a molecular weight of 500 or more and less than 2,000, and a low molecular compound having a hydrophilic group. Specifically, a compound in which a part of a hydrogen atom of a hydroxyl group of a compound having a plurality of phenol skeletons is substituted with the above-mentioned acid dissociable dissolution inhibiting group or the like.

Further, in the component (A2), "low molecular compound" means a compound which is not a resin component.

(A2) component, for example, a sensitizer in a g-line or i-line resist which is known to be a non-chemically amplified type, or a part of a hydrogen atom of a hydroxyl group of a low molecular weight phenol compound of a heat-resistant enhancer is dissociated by the above acid Substituted for dissolution inhibition The composition is preferred, and the aforementioned ingredients can be used arbitrarily.

The low molecular weight phenol compound, for example, bis(4-hydroxyphenyl)methane, bis(2,3,4-trihydroxyphenyl)methane, 2-(4-hydroxyphenyl)-2-(4'-hydroxyl Phenyl)propane, 2-(2,3,4-trihydroxyphenyl)-2-(2',3',4'-trihydroxyphenyl)propane, tris(4-hydroxyphenyl)methane, double (4-hydroxy-3,5-dimethylphenyl)-2-hydroxyphenylmethane, bis(4-hydroxy-2,5-dimethylphenyl)-2-hydroxyphenylmethane, bis (4 -hydroxy-3,5-dimethylphenyl)-3,4-dihydroxyphenylmethane, bis(4-hydroxy-2,5-dimethylphenyl)-3,4-dihydroxyphenylmethane , bis(4-hydroxy-3-methylphenyl)-3,4-dihydroxyphenylmethane, bis(3-cyclohexyl-4-hydroxy-6-methylphenyl)-4-hydroxyphenylmethane , bis(3-cyclohexyl-4-hydroxy-6-methylphenyl)-3,4-dihydroxyphenylmethane, 1-[1-(4-hydroxyphenyl)isopropyl]-4-[ 1,2-bis(4-hydroxyphenyl)ethyl]benzene, phenol, m-cresol, p-cresol or xylenol, etc., 2, 3, 4 nucleus of a formalin condensate of phenols. Of course, it is not limited to this.

The acid dissociable dissolution inhibiting group is not particularly limited, and for example, it can be as described above.

(A) Ingredients may be used alone or in combination of two or more.

In the photoresist composition of the present invention, the content of the component (A) may be adjusted in accordance with the thickness of the photoresist film to be formed.

<(B) ingredients>

The component (B) is an acid generator (B1) (hereinafter, also referred to as a component (B1)) which is formed by containing the compound represented by the above formula (b1-1). The The component (B1) is the same as the above-mentioned compound (B1) of the present invention.

(B1) The components may be used alone or in combination of two or more.

Further, in the photoresist composition of the present invention, the content of the component (B1) in the component (B) is preferably 40% by mass or more, more preferably 70% by mass or more, and may be 100% by mass. The best is 100% by mass. When the photoresist pattern of the present invention is used to form a photoresist pattern, the lithographic etching characteristics such as resolution and line width unevenness (LWR) can be improved.

In the component (B), the acid generator (B2) other than the component (B1) (hereinafter also referred to as the component (B2)) may be used in combination with the component (B1).

The component (B2) is not particularly limited as long as it is a component other than the component (B1), and a component which has been proposed as an acid generator for chemically amplified photoresist has been used.

The acid generator is, for example, a sulfonium acid generator such as an iodonium salt or a sulfonium salt, an oxime sulfonate acid generator, a dialkyl or bisarylsulfonyldiazomethane, or a polysulfonate. Hydrazine-based diazomethane-based acid generator, nitrobenzyl sulfonate-based acid generator, iminosulfonate-based acid generator, diterpenoid acid generator, etc. Compound.

As the onium salt acid generator, for example, a compound represented by the following formula (b-1) or (b-2) can be used.

Wherein R ^1" to R ^3" and R ^5" to R ^6" each independently represent an aryl group or an alkyl group; and any of R ^1" to R ^3" in the formula (b-1) may be Bonding to each other and forming a ring together with a sulfur atom in the formula; R ^4" is a linear, branched or cyclic alkyl group or a fluorinated alkyl group; at least one of R ^1" to R ^3" is an aryl group, R ^{5 "to} R ^6" in at least one aryl group].

In the formula (b-1), R ^1" to R ^3" are each independently an aryl group or an alkyl group; and in the formula (b-1), any one of R ^1" to R ^3" may be bonded to each other and The sulfur atoms in the formula may form a ring together.

And, R ^{1 "to} R ^3", at least one aryl group. It is preferable that two or more of R ^1′′ to R ^3′′ are aryl groups, and those in which R ^1′′ to R ^{3′′ are} all aryl groups are preferred.

The aryl group of R ^1" to R ^3" is not particularly limited, and is, for example, an aryl group having 6 to 20 carbon atoms, and a part or all of a hydrogen atom of the aryl group may be an alkyl group or an alkoxy group. A halogen atom, a hydroxyl group or the like may be substituted or unsubstituted. From the viewpoint of inexpensive synthesis of an aryl group, it is preferred to use an aryl group having 6 to 10 carbon atoms. Specifically, for example, a phenyl group, a naphthyl group or the like.

The alkyl group which may be substituted for the hydrogen atom of the above aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.

The alkoxy group which may replace the hydrogen atom of the aforementioned aryl group, having a carbon number of 1 The alkoxy group of ~5 is preferred, and the methoxy group and the ethoxy group are preferred.

The halogen atom which can replace the hydrogen atom of the above aryl group is preferably a fluorine atom.

The alkyl group of R ^1" to R ^3" is not particularly limited, and may be, for example, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms. In terms of excellent resolution, it is preferable to use a carbon number of 1 to 5. Specifically, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an anthracenyl group, an anthracenyl group and the like. From the viewpoint of having excellent resolution and being inexpensively synthesized, it is more preferable to use a methyl group.

Among them, those in which R ^{1 "} to R ^{3 "} are each a phenyl group or a naphthyl group are preferred.

In the case of R ^1" to R ^3" in the formula (b-1), any two of them may be bonded to each other and form a ring together with the sulfur atom in the formula to form a 3 to 10 member ring containing a sulfur atom. Good, it is better to form a ring containing 5 to 7 members.

In the case where any two of R ^1" to R ^3" in the formula (b-1) may be bonded to each other and form a ring together with the sulfur atom in the formula, the remaining one is preferably an aryl group. The aforementioned aryl group is, for example, the same as the above-mentioned aryl group of R ^1" to R ^3" .

R ^4" is a linear, branched or cyclic alkyl group, or a linear, branched or cyclic fluorinated alkyl group.

The linear or branched alkyl group is preferably a carbon number of 1 to 10, more preferably a carbon number of 1 to 8, and most preferably a carbon number of 1 to 4.

The cyclic alkyl group is a cyclic group represented by the above R ^{1 "} , and preferably has a carbon number of 4 to 15, preferably a carbon number of 4 to 10, and a carbon number of 6 to 10. good.

The fluorinated alkyl group is preferably one having a carbon number of 1 to 10, more preferably having a carbon number of 1 to 8, and preferably having a carbon number of 1 to 4. Further, the fluorination ratio of the fluorinated alkyl group (the ratio of the fluorine atom in the alkyl group) is preferably from 10 to 100%, more preferably from 50 to 100%, particularly the fluorinated alkyl group in which all hydrogen atoms are replaced by fluorine atoms. (Perfluoroalkyl group) is more preferred because its acid strength is stronger.

R ^{4" is} preferably a linear or cyclic alkyl group, or a linear, branched or cyclic fluorinated alkyl group.

In the formula (b-2), R ^5" to R ^6" are each independently an aryl group or an alkyl group; at least one of R ^5" to R ^6" is an aryl group, and all of R ^5" to R ^6" are The aryl group is the best.

The aryl group of R ^5" to R ^6" is, for example, the same as the aryl group of R ^1" to R ^3" .

The alkyl group of R ^5" to R ^6" is, for example, the same as the alkyl group of R ^1" to R ^3" .

Among them, those in which R ^5" to R ^{6" are} all phenyl groups are preferred.

(B-2) in the above formula R ^{4 "and} (b-1) in the R ^4" is the same as the contents.

Specific examples of the sulfonium acid generators represented by the formulae (b-1) and (b-2), for example, diphenyl iodonium trifluoromethanesulfonate or nonafluorobutane sulfonate, bis (4-tert) -butylphenyl)iodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, triphenylsulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or its nonafluorobutanesulfonate , tris(4-methylphenyl)phosphonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, dimethyl(4-hydroxynaphthyl)phosphonium trifluoromethanesulfonate Acid ester, its heptafluoropropane sulfonate or its nine Fluorobutanesulfonate, triphenylmethanesulfonate of monophenyldimethylhydrazine, heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonic acid of diphenylmonomethylhydrazine Ester, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, (4-methylphenyl)diphenylphosphonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonic acid Ethyl ester, (4-methoxyphenyl)diphenylphosphonium trifluoromethanesulfonate, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, tris(4-tert-butyl)phenyl hydrazine Trifluoromethanesulfonate, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, diphenyl(1-(4-methoxy)naphthyl)phosphonium trifluoromethanesulfonate, heptafluoropropane a sulfonate or a nonafluorobutane sulfonate thereof, a trifluoromethanesulfonate of bis(1-naphthyl)phenylhydrazine, a heptafluoropropane sulfonate thereof or a nonafluorobutane sulfonate thereof, a 1-phenyl group Trifluoromethanesulfonate of tetrahydrothiophene, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, trifluoromethanesulfonate of 1-(4-methylphenyl)tetrahydrothiophene, Heptafluoropropane sulfonate or its nonafluorobutane Acid ester, trifluoromethanesulfonate of 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophene, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, 1-( 4-methoxynaphthalen-1-yl)tetrahydrothiophene trifluoromethanesulfonate, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, 1-(4-ethoxynaphthalene-1- Trifluorothiophene trifluoromethanesulfonate, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiophene Trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, triphenylmethanesulfonate of 1-phenyltetrahydrothiopyranium, its heptafluoropropane sulfonate or its nonafluorobutane Sulfonic acid ester, trifluoromethanesulfonate of 1-(4-hydroxyphenyl)tetrahydrothiopyrene, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, 1-(3,5-dimethyl 4-hydroxyphenyl) Trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, 1-(4-methylphenyl)tetrahydrothiopyranium trifluoromethanesulfonate And heptafluoropropane sulfonate or its nonafluorobutane sulfonate.

Further, an anthracene salt in which the anion portion of the above-mentioned phosphonium salt is substituted with methanesulfonate, n-propanesulfonate, n-butanesulfonate or n-octanesulfonate can be used.

Further, in the above formula (b-1) or (b-2), the anthracene salt-based acid generator obtained by substituting an anion moiety with an anion moiety represented by the following formula (b-3) or (b-4) may be used. Alternatively, the cationic moiety may be the same as the above formula (b-1) or (b-2).

[wherein, X" is an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom; Y" and Z" are each independently a carbon number of 1 to 10 in which at least one hydrogen atom is replaced by a fluorine atom. Alkyl].

X" is a linear or branched alkyl group in which at least one hydrogen atom is replaced by a fluorine atom, and the carbon number of the alkyl group is preferably from 2 to 6, more preferably from 3 to 5, most preferably Carbon number 3.

Y′′, Z′′ each independently is a linear or branched alkyl group in which at least one hydrogen atom is replaced by a fluorine atom, and the carbon number of the alkyl group is preferably from 1 to 10, more preferably from 1 to 7, carbon atoms. The best carbon number is 1~3.

When the carbon number of the alkyl group of X" or the carbon number of the alkyl group of Y" or Z" is in the above carbon number range, based on the reason that the solubility of the solvent is excellent, The smaller the better.

Further, in the alkyl group of X" or the alkyl group of Y" or Z", the more the number of hydrogen atoms substituted by fluorine atoms, the stronger the strength of the acid, and the higher energy light or electron line with respect to 200 nm or less. Preferably, the transparency is improved by the ratio of the fluorine atom in the alkyl group or the alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably A perfluoroalkylene or perfluoroalkyl group in which all hydrogen atoms are replaced by fluorine atoms.

Further, an onium salt having a cationic portion represented by the following formula (b-5) or (b-6) can be used as the onium salt acid generator.

Wherein R ⁴¹ to R ⁴⁶ are each independently an alkyl group, an ethyl group, an alkoxy group, a carboxyl group, a hydroxyl group or a hydroxyalkyl group; n ₁ to n ₅ are each independently an integer of 0 to 3, and n ₆ is An integer from 0 to 2].

In R ⁴¹ to R ⁴⁶ , the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group, and a methyl group, an ethyl group, a propyl group or an isopropyl group. The base, n-butyl, or tert-butyl are particularly preferred.

The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, wherein the alkoxy group is linear Further, a branched alkoxy group is more preferable, and a methoxy group or an ethoxy group is particularly preferred.

The hydroxyalkyl group is preferably a group in which one or a plurality of hydrogen atoms of the above alkyl group are substituted by a hydroxyl group, such as a methylol group, a hydroxyethyl group, a hydroxypropyl group or the like.

When the symbols n ₁ to n ₆ attached to R ⁴¹ to R ⁴⁶ are integers of 2 or more, the plural R ⁴¹ to R ⁴⁶ may be the same or different.

n _{1 is} preferably 0 to 2, more preferably 0 or 1, and most preferably 0.

n ₂ and n _{3 are} preferably each independently 0 or 1, more preferably 0.

n _{4 is} preferably 0 to 2, more preferably 0 or 1.

n _{5 is} preferably 0 or 1, more preferably 0.

n _{6 is} preferably 0 or 1, more preferably 1.

The anion portion having a sulfonium salt of the cation portion represented by the formula (b-5) or (b-6) is not particularly limited, and it can be used in the same manner as the anion portion currently proposed as the sulfonium acid generator. Anion part. The anion portion is, for example, a fluorinated alkylsulfonic acid ion such as an anion portion (R ^{4 "} SO ₃ ^- ) of the sulfonium salt generator represented by the above formula (b-1) or (b-2); An anion moiety represented by the formula (b-3) or (b-4), wherein a fluorinated alkylsulfonic acid ion is preferred, and a fluorinated alkylsulfonic acid ion having a carbon number of 1 to 4 is more preferred. It is preferred to use a linear perfluoroalkylsulfonic acid ion having a carbon number of 1 to 4. Specifically, for example, a trifluoromethanesulfonate ion, a heptafluoro-n-propylsulfonate ion, and a nonafluoro-n-butyl group. Sulfonic acid ion and the like.

In the present specification, the oxime sulfonate-based acid generator has, for example, a compound having at least one group represented by the following formula (B-1), which has a property of generating an acid by radiation irradiation. The above-mentioned sulfonate-based acid generator is generally used for a chemically amplified positive-type photoresist composition, and the invention can be arbitrarily selected. use.

[In the formula (B-1), R ³¹ and R ³² are each independently an organic group].

The organic group of R ³¹ and R ³² is a group containing a carbon atom, but it may also contain an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (a fluorine atom, a chlorine atom, etc.), etc.) ).

The organic group of R ³¹ is preferably a linear, branched or cyclic alkyl group or an aryl group. The aforementioned alkyl group or aryl group may have a substituent. The substituent is not particularly limited, and examples thereof include a fluorine atom, a linear one having a carbon number of 1 to 6, a branched or a cyclic alkyl group, and the like. Here, the "having a substituent" means that a part or the whole of a hydrogen atom of an alkyl group or an aryl group is substituted by a substituent.

The alkyl group has a carbon number of 1 to 20, preferably a carbon number of 1 to 10, preferably a carbon number of 1 to 8, preferably a carbon number of 1 to 6, and a carbon number of 1 to 4. . Among them, an alkyl group is particularly preferably an alkyl group (hereinafter, also referred to as a halogenated alkyl group) obtained by partial or complete halogenation. Further, a partially halogenated alkyl group means an alkyl group in which a part of a hydrogen atom is substituted by a halogen atom, and a completely halogenated alkyl group means an alkyl group in which a hydrogen atom is entirely substituted by a halogen atom. The halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.

The aryl group is preferably a carbon number of 4 to 20, preferably a carbon number of 4 to 10, and a carbon number of 6 to 10. The aryl group is particularly preferably an aryl group obtained by partially or completely halogenating. Further, a partially halogenated aryl group means one of hydrogen atoms The aryl group partially substituted by a halogen atom and the completely halogenated aryl group mean the aryl group in which all hydrogen atoms are replaced by a halogen atom.

R ^{31 is} particularly preferably an alkyl group having 1 to 4 carbon atoms or a fluorinated alkyl group having 1 to 4 carbon atoms which has no substituent.

The organic group of R ³² is preferably a linear, branched or cyclic alkyl group, an aryl group or a cyano group. The alkyl group or the aryl group of R ³² is, for example, the same as the alkyl group or the aryl group exemplified in the above R ³¹ .

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

The oxime sulfonate-based acid generator is more preferably a compound represented by the following formula (B-2) or (B-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 group having no substituent or an alkyl group having a halogenated group]

[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 2 or 3 valent aromatic hydrocarbon group; and R ³⁸ is an alkyl group having no substituent or Halogenated alkyl group, p" is 2 or 3].

In the above formula (B-2), the alkyl group or the halogenated alkyl group having no substituent of R ³³ is preferably a carbon number of 1 to 10, more preferably a carbon number of 1 to 8, and a carbon number of 1 to 6. optimal.

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

The fluorinated alkyl group in R ³³ is preferably one in which the hydrogen atom in the alkyl group is fluorinated by 50% or more, more preferably 70% or more, and more preferably 90% or more.

The aryl group of R ³⁴ , for example, a ring of an aromatic hydrocarbon such as a phenyl group or a biphenyl group, a fluorenyl group, a naphthyl group, an anthyl group or a phenanthryl group, which removes a hydrogen atom group, And a heteroaryl group obtained by substituting a part of a carbon atom of the ring of the above-mentioned group with a hetero atom such as an oxygen atom, a sulfur atom or a nitrogen atom. Among them, the base is better.

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 the halogenated alkyl group in the substituent is preferably a carbon number of 1 to 8, and more preferably a carbon number of 1 to 4. Further, the halogenated alkyl group is more preferably a fluorinated alkyl group.

The alkyl group or the halogenated alkyl group having no substituent of R ³⁵ is preferably a carbon number of 1 to 10, more preferably a carbon number of 1 to 8, and most preferably a carbon number of 1 to 6.

R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.

The fluorinated alkyl group in R ³⁵ preferably has a hydrogen atom of an alkyl group of 50% or more, more preferably 70% or more, and when it is fluorinated by 90% or more, the acid produced can be increased. For better. The most preferred is a perfluorinated alkyl group in which the hydrogen atom is 100% replaced by fluorine.

In the above formula (B-3), the alkyl group or the halogenated alkyl group having no substituent of R ³⁶ is, for example, the same as the alkyl group or the halogenated alkyl group having no substituent represented by the above R ³³ .

The 2 or 3 valent aromatic hydrocarbon group of R ³⁷ is, for example, a group obtained by further removing 1 or 2 hydrogen atoms from the aryl group of the above R ³⁴ .

R ³⁸ the alkyl group having no substituent or a halogenated alkyl group of, for example, as shown in the above-described R ³⁵ alkyl group or a halogenated alkyl group having no substituent group of the same content.

p" is preferably 2.

Specific examples of the sulfonate-based acid generator, such as α-(p-toluenesulfonyloxyimido)-benzyl cyanide (cyanide), α-(p-chlorophenylsulfonyloxyimino) -benzyl cyanide, α-(4-nitrophenylsulfonyloxyimido)-benzyl cyanide, α-(4-nitro-2-trifluoromethylbenzenesulfonyloxyimido)- Benzyl cyanide, α-(phenylsulfonyloxyimido)-4-chlorobenzyl cyanide, α-(phenylsulfonyloxyimido)-2,4-dichlorobenzyl cyanide, --(phenylsulfonyloxyimino)-2,6-dichlorobenzyl cyanide, α-(phenylsulfonyloxyimino)-4-methoxybenzyl cyanide, α-(2 -Chlorobenzenesulfonyloxyimido)-4-methoxybenzyl cyanide, α-(phenylsulfonyloxyimino)-thien-2-ylacetonitrile, α-(4-dodecane Benzosulfonyloxyimido)-benzyl cyanide, α-[(p-toluenesulfonyloxyimido)-4-methoxyphenyl]acetonitrile, α-[(dodecylbenzenesulfonate)醯 oxyimino)-4-methoxyphenyl]acetonitrile, α-(p-toluenesulfonyloxyimino)-4-thyl cyanide, α-(methylsulfonyloxyimino) -1- ring Pentenyl acetonitrile, α-(methylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(methylsulfonyloxyimido)-1-cycloheptenylacetonitrile, α-( Methylsulfonyloxyimino)-1-cyclooctenyl Acetonitrile, α-(trifluoromethylsulfonyloxyimido)-1-cyclopentenylacetonitrile, α-(trifluoromethylsulfonyloxyimido)-cyclohexylacetonitrile, α-(ethylsulfonate醯 oxyimino)-ethyl acetonitrile, α-(propylsulfonyloxyimino)-propyl acetonitrile, α-(cyclohexylsulfonyloxyimido)-cyclopentylacetonitrile, α-(ring Hexyl sulfoximine oxyimino)-cyclohexylacetonitrile, α-(cyclohexylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(ethylsulfonyloxyimino)-1-ring Pentenyl acetonitrile, α-(isopropylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(n-butylsulfonyloxyimino)-1-cyclopentenylacetonitrile, --(ethylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(isopropylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(n-butyl Sulfonoxyimino)-1-cyclohexenylacetonitrile, α-(methylsulfonyloxyimino)-phenylacetonitrile, α-(methylsulfonyloxyimino)-p-methoxy Phenyl acetonitrile, α-(trifluoromethylsulfonyloxyimido)-phenylacetonitrile, α-(trifluoromethylsulfonyloxyimino)-p-methoxyphenyl B , α-(ethylsulfonyloxyimido)-p-methoxyphenylacetonitrile, α-(propylsulfonyloxyimino)-p-methylphenylacetonitrile, α-(methylsulfonate醯 oxyimino)-p-bromophenylacetonitrile and the like.

Further, the oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [Chem. 18] to [Chem. 19]), WO2004/074242A2 (pp. 65-85) The sulfonate-based acid generator disclosed in Examples 1 to 40) may also be used in combination.

Further, for example, a compound shown below or the like is suitable.

Specific examples of the dialkyl or bisarylsulfonyldiazomethane in the diazomethane acid generator, such as bis(isopropylsulfonyl)diazomethane or bis(p-toluenesulfonyl) Diazomethane, bis(1,1-dimethylethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(2,4-dimethylphenylsulfonyl) Diazomethane, etc.

Further, the diazomethane-based acid generator disclosed in JP-A-H11-035551, JP-A-H11-035552, and JP-A-11-035573 is also suitable.

Further, poly(disulfonyl)diazomethane, for example, 1,3-bis(phenylsulfonyldiazomethylsulfonyl)propane disclosed in JP-A-11-322707, 1,4- Bis(phenylsulfonyldiazomethylsulfonyl)butane, 1,6-bis(phenylsulfonyldiazomethylsulfonyl)hexane, 1,10-bis(phenylsulfonate) Base heavy nitrogen methylsulfonyl) decane, 1,2-bis(cyclohexylsulfonyldiazomethylsulfonyl)ethane, 1,3-bis(cyclohexylsulfonyldiazomethylsulfonate) Mercapto)propane, 1,6-bis(cyclohexylsulfonyldiazomethylsulfonyl)hexane, 1,10-bis(cyclohexylsulfonyldiazomethylsulfonyl)decane, and the like.

(B2) The component may be used alone or in combination with one of the foregoing acid generators. The above combination can also be used.

In the photoresist composition of the present invention, the content of the component (B) is 0.5 to 30 parts by mass, preferably 1 to 20 parts by mass, per 100 parts by mass of the component (A). In the above range, the pattern can be sufficiently formed. And a uniform solution can be obtained with good preservation stability.

<arbitrary ingredients>

In the photoresist composition of the present invention, when the post exposure stability of the latent image formed by the pattern-wise exposure of the resist layer, the nitrogen content of any component may be further added. Organic compound (D) (hereinafter also referred to as (D) component).

As the component (D), proposals have been made for various compounds, and any of the known components may be used, and among them, an aliphatic amine, particularly a secondary aliphatic amine or a tertiary aliphatic amine is preferred. The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group is preferably one having a carbon number of from 1 to 12.

An aliphatic amine such as an amine (alkylamine or alkanolamine) or a cyclic amine obtained by substituting at least one hydrogen atom of ammonia NH ₃ with an alkyl group or a hydroxyalkyl group having 12 or less carbon atoms.

Specific alkylamines and alkanolamines such as n-hexylamine, n-heptylamine, n-octylamine, n-decylamine, n-decylamine, etc.; monoethylamine; a dialkylamine such as -n-propylamine, di-n-heptylamine, di-n-octylamine or dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine , tri-n-butylamine, tri-n-hexylamine, tri-n-pentylamine, tri-n-heptylamine, tri-n-octyl a trialkylamine such as an amine, tri-n-decylamine, tri-n-decylamine or tri-n-dodecylamine; diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine An alkanolamine such as di-n-octanolamine or tri-n-octanolamine. Among them, a trialkylamine in which three alkyl groups having 5 to 10 carbon atoms are bonded to a nitrogen atom is preferred, and tri-n-pentylamine is preferred.

The cyclic amine is, for example, a heterocyclic compound containing a nitrogen atom as a hetero atom. The heterocyclic compound may be a monocyclic compound (aliphatic monocyclic amine) or a polycyclic compound (aliphatic polycyclic amine).

The aliphatic monocyclic amine is specifically, for example, piperidine, piperazine or the like.

The aliphatic polycyclic amine is preferably a carbon number of 6 to 10, specifically, for example, 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diaza Ring [5.4.0]-7-undecene, hexamethylenetetramine, 1,4-diazabicyclo[2.2.2]octane, and the like.

They may be used alone or in combination of two or more.

(D) The component (A) component is 100 parts by mass, and is generally used in the range of 0.01 to 5.0 parts by mass.

The photoresist composition of the present invention is used to prevent the deterioration of the sensitivity, or the post exposure stability of the latent image formed by the pattern-wise exposure of the resist layer. The objective is to further contain at least one compound (E) (hereinafter also referred to as (E) component) selected from the group consisting of an organic carboxylic acid of any composition or an oxoacid of phosphorus or a derivative thereof.

An organic carboxylic acid such as acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid or the like is preferred.

Phosphorus oxyacids such as phosphoric acid, Phosphonic acid, Phosphinic acid, etc., wherein phosphonic acid is preferred.

The phosphorus oxyacid derivative is, for example, an ester group obtained by substituting a hydrogen atom of the oxo acid with a hydrocarbon group, and the hydrocarbon group is, for example, an alkyl group having 1 to 5 carbon atoms or an aryl group having 6 to 15 carbon atoms.

The phosphoric acid derivative is, for example, a phosphate such as di-n-butyl phosphate or diphenyl phosphate.

Phosphonic acid derivatives such as chromic acid esters such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, dibenzyl phosphonate, and the like.

Phosphinic acid derivatives such as phosphinates such as phenylphosphinic acid.

(E) The components may be used singly or in combination of two or more.

The component (E) is preferably an organic carboxylic acid, particularly salicylic acid.

The component (E) is usually used in an amount of 0.01 to 5.0 parts by mass based on 100 parts by mass of the component (A).

The photoresist composition of the present invention may be further blended with an additive which is suitable for mixing, for example, an additive resin which can improve the properties of the photoresist film, a surfactant for improving coating properties, a dissolution inhibitor, a plasticizer, and a stabilizer. , colorants, halo inhibitors, dyes, and the like.

[Organic Solvent (S)]

The photoresist composition of the present invention can be produced by dissolving a material in an organic solvent (S) (hereinafter also referred to as (S) component).

The (S) component may be used as long as it is a solvent which can be used to form a uniform solution. For example, one or two or more kinds of the above-mentioned known solvents can be used as a chemically amplified resist solvent.

For example, lactones such as γ-butyrolactone, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentanone, methyl isoamyl ketone, and 2-heptanone; ethylene glycol, Polyols such as ethylene glycol, propylene glycol, dipropylene glycol and derivatives thereof; esters of ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate a compound to be bonded; an ether having a monoalkyl ether or a monophenyl ether such as a monomethyl ether, a monoethyl ether, a monopropyl ether or a monobutyl ether as described above or a compound having an ester bond; a derivative of a polyol such as a bonded compound (in which propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME) is preferred); a cyclic ether such as dioxane; Or methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxy propionate, etc. Ester; anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenyl ether, butyl phenyl ether, ethyl benzene, diethyl benzene, pentyl , Isopropylbenzene, toluene, xylene, cymene, trimethylbenzene aromatic organic solvent.

The above organic solvent may be used singly or in combination of two or more kinds. Forms can also be used.

Further, among them, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and ethyl lactate (EL) are preferably used.

Further, a mixed solvent obtained by mixing PGMEA with a polar solvent is preferred, and the addition ratio (mass ratio) may be appropriately determined depending on the compatibility of PGMEA with a polar solvent, etc., preferably from 1:9 to 9:1. More preferably, it is in the range of 2:8 to 8:2.

More specifically, when the polar solvent is ethyl lactate (EL), the mass of PGMEA:EL is preferably from 1:9 to 9:1, more preferably from 2:8 to 8:2. When the polar solvent is PGME, the mass of PGMEA:PGME is preferably from 1:9 to 9:1, more preferably from 2:8 to 8:2, most preferably from 3:7 to 7:3.

Further, among the components (S), for example, a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is preferably used. At this time, in the mixing ratio, the quality of the former and the latter is preferably 70:30 to 95:5.

The amount of the component (S) is not particularly limited. Generally, it can be appropriately selected in accordance with the concentration applied to the substrate, the thickness of the coating film, etc., and generally the solid concentration in the photoresist composition is 2-20. The mass% is preferably used in the range of 5 to 15% by mass.

Method for forming photoresist pattern

The method for forming a photoresist pattern of the present invention comprises the steps of forming a photoresist film on a support by using the photoresist composition of the present invention described above, and forming the light The step of exposing the resist film, the step of developing the photoresist film to form a photoresist pattern.

The method of forming the photoresist pattern of the present invention can be carried out, for example, in the following manner.

That is, first, the photoresist composition of the present invention is applied onto a support by a spin coater or the like, and then subjected to a temperature of 80 to 150 ° C for 40 to 120 seconds, preferably 60 to 60. After 90 seconds of post-apply bake (PAB), for example, by ArF excimer laser light, and then using ArF excimer laser light, after selective exposure by the desired mask pattern And then exposed to a temperature of 80 to 150 ° C for 40 to 120 seconds, preferably 60 to 90 seconds of exposure (Post exposure bake, PEB). Next, it is subjected to development treatment using an alkali developing solution, for example, 0.1 to 10% by mass of a tetramethylammonium hydroxide (TMAH) aqueous solution, preferably washed with pure water and then dried. Further, if necessary, baking treatment (post-baking) may be performed after the above development treatment. In this way, a photoresist pattern of a faithful response mask pattern can be obtained.

The support is not particularly limited, and conventionally known articles such as a substrate for an electronic component or an article on which a specific wiring pattern is formed may be used. More specifically, for example, a substrate made of a metal such as a germanium wafer, copper, chromium, iron, or aluminum, or a glass substrate. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold, or the like can be used.

Further, for the support, for example, an inorganic or/or organic film may be provided on the substrate. An inorganic film such as an inorganic antireflection film (inorganic BARC). Organic film, such as organic anti-reflective film (organic BARC )Wait.

The wavelength used for the exposure is not particularly limited, and an ArF excimer laser, a KrF excimer laser, an F ₂ excimer laser, an EUV (very ultraviolet ray), a VUV (vacuum ultraviolet ray), or an EB (electron line) can be used. ), X-ray, soft X-ray and other radiation. The above photoresist composition is effective for KrF excimer laser, ArF excimer laser, EB or EUV, especially for ArF excimer laser.

The exposure of the photoresist film can be performed by usual exposure (dry exposure) in an inert gas such as air or nitrogen, or by immersion exposure.

The immersion exposure, as described above, is the portion between the lens filled with an inert gas such as air or nitrogen and the photoresist film on the wafer, which is filled with a refractive index higher than that of air. The exposure was carried out in the state of the solvent (immersion medium).

More specifically, the immersion exposure is such that a solvent having a refractive index higher than that of air (infiltrated medium) is filled between the photoresist film obtained as described above and the lens at the lowest position of the exposure device. In the state, exposure is performed by the desired reticle pattern (immersion exposure).

The immersion medium is preferably a solvent having a refractive index smaller than that of air and having a refractive index smaller than that of the resist film exposed by the immersion exposure. The refractive index of the solvent is not particularly limited as long as it is within the above range.

A solvent having a refractive index larger than that of air and having a refractive index smaller than that of the photoresist film, for example, water, a fluorine-based inert liquid, an oxime-based solvent, a hydrocarbon-based solvent, or the like.

Specific examples of the fluorine-based inert liquid, such as a liquid such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , C ₅ H ₃ F ₇ or the like, and a boiling point It is preferably from 70 to 180 ° C, and more preferably from 80 to 160 ° C. In the fluorine-based inert liquid, when the boiling point is in the above range, the medium used for the wetting type can be removed by a simple method after the completion of the exposure, and is preferable.

The fluorine-based inert liquid is particularly preferably a perfluoroalkyl compound obtained by substituting all hydrogen atoms in the alkyl group with fluorine atoms. The perfluoroalkyl compound is specifically, for example, a perfluoroalkyl ether compound or a perfluoroalkylamine compound.

Further, more specifically, the perfluoroalkyl ether compound is, for example, perfluoro(2-butyl-tetrahydrofuran) (boiling point: 102 ° C), and the above perfluoroalkylamine compound, for example, perfluorotributylamine (boiling point 174) °C) and so on.

The above-described photoresist composition of the present invention has a novelty that has not been known in the past.

Further, in the photoresist composition of the present invention, the lithographic etching characteristics such as sensitivity and resolution are also good, and for example, a fine photoresist pattern having a line width of a line and a space pattern of 120 nm or less can be formed. Moreover, in the case of forming a photoresist pattern using a conventional photoresist composition, it is often caused that the substrate interface is reduced in rigidity due to the bottom enlargement (bottom pull) of the photoresist pattern, and the resist pattern shape is likely to occur. A problem with the defect, but when the photoresist composition of the present invention is used, a photoresist pattern having a low bottom pull can be formed.

Further, the component (B1) used in the photoresist composition of the present invention is lower than 200 nm in comparison with an acid generator used in a conventional chemically amplified photoresist composition, for example, a triphenylsulfonium salt. It is a light with a wavelength of about 193 nm which has a higher transparency. Therefore, the photoresist composition of the present invention In the comparison with the conventional photoresist composition, the addition amount of the component (B) can be increased.

Further, the component (B1) is excellent in acid generation efficiency upon exposure, and when the component (B1) is contained as the component (B), the photoresist composition of the present invention can have a good sensitivity.

These effects are presumably mainly affected by the structure of the cation portion of the (B1) component.

Further, the component (B1) is presumed to be affected by the anion portion having a structure in which a functional group of "R ¹ -O-[CO] _n -" is introduced into the Y ¹ -SO ₃ ^- skeleton. That is, in the anion portion having such a structure, the carbon number of the alkyl group which may be substituted by fluorine in Y ¹ is divided into a small value of 1 to 4, and an anion of a conventional acid generator such as nonafluorobutanesulfonate When the parts are compared, excessive diffusion of the acid after exposure can also be suppressed. Therefore, a photoresist pattern having good lithography etching characteristics can be formed.

Further, in the component (B1), Y ¹ is a alkylene chain having 1 to 4 carbon atoms which may be substituted by fluorine, and when compared with a property in which a perfluoroalkyl chain having 6 to 10 carbon atoms is difficult to decompose, From the viewpoint of considering bioreduction, it is safer to handle.

[Examples]

In the following, the invention will be described in more detail by way of examples, but the invention is not limited by the examples.

[Example 1]

5 ml of tetrahydrofuran was added to 1.0 g of allyloxytetrafluoroethane sulfonium fluoride, and an aqueous solution obtained by dissolving 2.8 ml of pure water containing 0.20 g of lithium hydroxide in the water bath was dropped into the solution, and then in a water bath. Stir. The absorption of the ¹⁹ F-NMR of -217.8 ppm obtained by -SO ₂ F disappeared, and it was confirmed that all of the fluorinated sulfonyl group was converted into lithium sulfonate. Thereafter, the reaction liquid was concentrated and dried to obtain a white viscous solid. The crude product was dissolved in 3.35 ml of acetone, and the by-product LiF was removed by filtration, and the filtrate was concentrated to obtain 0.58 g of the compound (1-1) represented by the following formula (1-1).

[52] H ₂ C==CHCH ₂ OCF ₂ CF ₂ SO ₃ ^- Li ⁺ (1-1)

Next, 10.00 g of diphenyliodonium methanesulfonate was dissolved in 50.00 g of water, and 6.81 g of the compound (1-1) was added thereto, and the mixture was stirred at room temperature for 1 hour. After completion of the reaction, 68.9 g of ethyl phthalate was added to carry out an extraction operation. After liquid separation, the organic layer was washed 5 times with 34.5 g of pure water. After washing, the obtained organic layer was concentrated to give 6.70 g of desired compound.

The obtained compound (hereinafter also referred to as compound (I-11)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.

¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 7.94 (d, 4H (H ^a )), 7.44 (d, 2H (H ^c )), 7.30 (t, 4H (H ^b )) 5.71-5.80 (m, 1H(H ^e )), 5.06-5.29 (m, 2H(H ^d )), 4.34 (d, 2H(H ^f )).

¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = -83.6, -115.7.

From the above results, it was confirmed that the compound (I-11) had the structure shown below.

3.93 g of the compound (I-11), 0.7745 g of pentamethyl sulfide, and 0.060 g of copper (II) benzoate were dissolved in 5.90 g of chlorobenzene, and the mixture was reacted at 100 ° C for 1 hour. After completion of the reaction, the reaction solution was concentrated to dryness and then dissolved in dichloromethane (26.2 g). The dichloromethane solution was washed with water and concentrated to give 0.84 g of the objective compound.

The obtained compound (hereinafter also referred to as compound (b1-11)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.

¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 8.10 (d, 2H (H ^c )), 7.59-7.69 (m, 3H (H ^a + H ^b )), 5.86-5.96 (m, 1H(H ^h )), 5.19-5.42 (m, 2H(H ^g )), 4.50 (d, 2H(H ⁱ )), 3.68-3.98 (m, 4H(H ^d )), 1.85-2.30 (m, 6H(H ^e +H ^f )).

¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = -79.9, -112.2.

From the above results, it was confirmed that the compound (b1-11) had the structure shown below.

[Example 2]

To 5.0 g of 2-naphthylmethyloxytetrafluoroethane sulfonium fluoride, 6.7 ml of 1 tetrahydrofuran was added, and an aqueous solution obtained by dissolving 13.6 ml of pure water of 0.98 g of lithium hydroxide was added dropwise in an ice bath. After the solution, it was stirred in an ice bath. When the absorption of -197.6 ppm of ¹⁹ F-NMR obtained by -SO ₂ F disappeared, it was confirmed that all of the fluorinated sulfonyl group was converted into lithium sulfonate. Thereafter, the reaction liquid was concentrated and dried to obtain a white viscous solid. The crude product was dissolved in 14.2 ml of acetone, and the by-product LiF was removed by filtration, and the filtrate was concentrated to give 5.50 g of the compound (1-2) represented by the following chemical formula (1-2).

Next, 7.64 g of diphenyliodonium methanesulfonate was dissolved in 38.02 g of water, and 7.30 g of the compound (1-2) was added thereto, and the mixture was stirred at room temperature for 1 hour. After completion of the reaction, 38.02 g of ethyl acetate was added to carry out an extraction operation. After liquid separation, the organic layer was washed 5 times with pure water 38.02 g. After washing, the obtained organic layer was crystallized from hexane, and the obtained powder was dried under reduced pressure to yield 10.

The obtained compound (hereinafter also referred to as compound (I-12)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.

¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 7.99-8.01 (d, 4H (H ^a )), 7.59 (s, 1H (H ^d )), 7.80-7.83 (m, 3H ( Phenyl + Naphtyl)), 7.39-7.58 (m, 9H (Phenyl + Naphtyl)), 5.20 (s, 2H (H ^e )).

¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = -79.0, -111.6.

From the above results, it was confirmed that the compound (I-12) had the structure shown below.

8.00 g of the compound (I-12), 1.32 g of pentamethyl sulfide, and 0.10 g of copper (II) benzoate were dissolved in 12.00 g of chlorobenzene, and reacted at 100 ° C for 1 hour. After completion of the reaction, the reaction mixture was concentrated to dryness and then dissolved in m. The dichloromethane solution was washed with water and concentrated to give 0.53 g of the objective compound.

The obtained compound (hereinafter also referred to as compound (b1-12)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.

¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 7.93 - 7.95 (d, 2H (H ^c )), 7.85 (s, 1H (H ^g )), 7.77-7.81 (m, 3H ( Phenyl+Naphtyl)), 7.46-7.56 (m, 6H (Phenyl+Naphtyl)), 5.21 (s, 2H(H ^h )), 3.48-3.79 (m, 4H(H ^d )), 1.68-2.13 (m, 6H (H ^e +H ^f )).

¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = -84.0, -116.5.

From the above results, it was confirmed that the compound (b1-12) had the following Show the structure.

[Comparative Example 1]

0.28 g of triphenylsulfonium bromide was dissolved in 5.0 ml of pure water, and 0.17 g of the compound (1-1) obtained in the same manner as in Example 1 was added to the solution, and the mixture was stirred at room temperature for 14 hours. After adding 10 ml of dichloromethane, the mixture was stirred, and the organic phase was separated and taken out. The organic phase was washed again with 5.0 ml of water in pure water, and the organic phase was taken out by liquid separation. The organic phase which was taken out was concentrated, and dried to give 0.16 g of the objective compound.

The obtained compound (hereinafter also referred to as compound (b2-11)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.

¹ H-NMR (acetone-d ₆ , 400 MHz): δ (ppm) = 8.30 to 7.60 (m, 15H (H ^a )), 5.91 (m, 1H (H ^b )), 5.47 (d, 1H (H ^c )), 5.16 (d, 1H(H ^d )), 4.48 (d, 2H(H ^e )).

¹⁹ F-NMR (acetone-d ₆ , 376 MHz): δ (ppm) = 79.8, 1121.

From the above results, it was confirmed that the compound had the structure shown below.

[Comparative Example 2]

6.90 g of triphenylsulfonium bromide was dissolved in 125 ml of pure water, and 5.50 g of the compound (1-2) obtained in the same manner as in Example 2 was added to the solution, and the mixture was stirred at room temperature for 19 hours, and then added. After stirring 125 ml of dichloromethane, the organic phase was separated and taken out.

The organic phase was washed again with 40 ml of pure water, and the organic phase was taken out by liquid separation. The organic phase which was taken out was concentrated, and dried to give the title compound 7.09 g. (Yield: 75.2%).

The obtained compound (hereinafter also referred to as compound (b2-12)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.

¹ H-NMR (acetone-d ₆ , 400 MHz): δ (ppm) = 8.01 to 7.47 (m, 22H (H ^a )), 5.23 (s, 2H (H ^b )).

¹⁹ F-NMR (acetone-d ₆ , 376 MHz): δ (ppm) = 79.2, 111.8.

From the above results, it was confirmed that the compound had the structure shown below.

[Example 3]

5.00 g of 1-(2-keto-2-phenylethyl)tetrahydrothiophene bromide was dissolved in 25 g of pure water, and 6.6 g of the compound (1-2) obtained in the same manner as in Example 2 was added. Therein, it was stirred at room temperature for 2 hours. Then, 25.0 g of dichloromethane was added, and the methylene chloride layer was separated, washed with dilute hydrochloric acid, washed with water, and then added to the methylene chloride layer, 250.0 g of n-hexane, white The objective compound was 8.5 g as a color solid.

The obtained compound (hereinafter also referred to as compound (b1-13)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below. From the results, it was confirmed that the compound (b1-13) had a structure represented by the above chemical formula.

¹ H-NMR (DMSO-d ₆ , 400 MHz): δ (ppm) = 7.88 - 8.01 (m, 6H (Ar)), 7.75 (t, 1H (Ar)), 7.61 (t, 2H (Ar)), 7.52-7.54 (m, 3H(Ar)), 5.34 (s, 2H(CH ₂ )), 5.20 (s, 2H(CH ₂ )), 3.48-3.59 (m, 4H(CH ₂ -CH ₂ )), 217-2.26 (m, 4H(CH ₂ -CH ₂ )).

¹⁹ F-NMR (acetone-d ₆ , 376 MHz): δ (ppm) = -79.6, -111.9.

[Solvent solubility evaluation]

The compounds (b1-11), (b1-12), (b1-13), (b2-11), (b2-12), and the following were obtained in the above Examples 1 to 3 and Comparative Examples 1 and 2, respectively. The compound (b2-13) represented by the formula (b2-13), The solvent solubility was evaluated in the following order.

In a general photoresist solvent, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethyl lactate (EL), each compound is added and changed at a dosage of 25 ° C. Stir for 30 minutes. After the completion of the stirring, the concentration (% by mass) in which each compound was completely dissolved was measured. The results are shown in Table 1.

As shown in Table 1, the compounds (b1-11) and (b1-12) and the compound (b2-13) of the present invention have extremely high solubility for PGMEA, PGME, and EL.

Further, the compound (b2-11) has a good solubility to PGME and EL, but is poor in solubility to PGMEA. Further, the compound (b2-12) is inferior in solubility in any solvent. Further, in the compound (b2-12), only the compound (b1-13) of the cationic moiety is changed, and the solubility to PGMEA can be improved.

[Examples 4 to 6, Comparative Example 3]

The components shown in Table 2 were mixed and dissolved to prepare a positive resist composition.

In Table 2, the numerical value in [] is the addition amount (parts by mass). Further, the symbols in Table 2 are as follows. Further, the amount of the component (B) added is equal to the molar amount.

(A)-1: a copolymer of Mw=7000, Mw/Mn=1.8 represented by the following chemical formula (A)-1 (wherein 1/m/n=45/35/20 (mole ratio)) .

(B)-1: Compound (b1-11) obtained in Example 1.

(B)-2: Compound (b1-12) obtained in Example 2.

(B)-3: Compound (b1-13) obtained in Example 3.

(B)-4: Compound (b2-13) represented by the above formula (b2-13).

(D)-1: Tri-n-pentylamine.

(E)-1: Salicylic acid.

(S)-1: γ-butyrolactone.

(S)-2: a mixed solvent of PGMEA/PGME=6/4 (mass ratio).

Using the resulting photoresist composition, a photoresist pattern was formed in the following order, and its lithographic etching characteristics were evaluated.

[analytical, sensitivity]

The organic anti-reflection film composition "ARC29A" (trade name, manufactured by Privah Technologies Co., Ltd.) was applied to a hot plate at 205 ° C for 60 seconds on a ruthenium wafer of 8 inches. After baking and drying under the conditions, an organic anti-reflection film having a film thickness of 82 nm was formed. Subsequently, the positive-type photoresist composition solution obtained above was separately applied to the anti-reflection film using a spin coater, and pre-baked (PAB) was performed on a hot plate at 110 ° C for 60 seconds. After the treatment, after drying, a photoresist film having a film thickness of 150 nm was formed.

Next, an ArF exposure apparatus NSR-S302 (manufactured by Ricoh Co., Ltd.; NA (number of openings) = 0.60, 2/3 wheel illumination) was used, and an ArF excimer laser (193 nm) was masked (6%). Tone) for selective illumination. Subsequently, post-exposure heating (PEB) treatment was carried out at 110 ° C for 60 seconds, and development was carried out at 23 ° C using a 2.38 mass % aqueous solution of tetramethylammonium hydroxide (TMAH) for 30 seconds. And then The mixture was washed with pure water for 30 seconds, and subjected to vibration drying.

As a result, in any of the examples, a photoresist pattern (L/S pattern) having a line width of 120 nm and a pitch of 240 nm and a space (1:1) was formed.

Further, an optimum exposure amount Eop (mJ/cm ² ) of the L/S pattern having a line width of 120 nm and a pitch of 240 nm was formed at this time, that is, sensitivity. The results are shown in Table 3.

"Line width unevenness (LWR)"

In each of the L/S patterns formed by the above Eop, a length measuring SEM (scanning electron microscope, trade name: S-9220, manufactured by Hitachi, Ltd.) was used, and the line width was measured in five places according to the length direction of the line. From the results, a three-fold value (3 s) of the standard deviation (s) was calculated as a scale of expression of LWR. The results are shown in Table 3. The smaller the 3s value is, the smaller the unevenness of the line width is, and the L/S pattern having a more uniform width is obtained.

As shown in Table 3, the photoresist compositions of Examples 4 to 6 all showed good LWR. Further, the photoresist composition of Comparative Example 3 showed a poor LWR.

Claims (13)

A photoresist composition comprising a substrate component (A) containing a change in solubility of an alkali developer via an action of an acid, and a photoresist composition of an acid generator component (B) which generates an acid by exposure The acid generator component (B) is an acid generator (B1) containing a compound represented by the following formula (b1-1). Wherein R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and when n1 is 1, R ¹ and R ³ may be bonded to each other, and The carbon atom of R ¹ bond and the carbon atom of R ³ bond form a ring of 3 to 7 member ring structure at the same time, and A is a ring of 3 to 7 ring structure which can form a ring with the A bond. The valence group, the ring may have a substituent, and R ² is a group represented by R ⁵³ -R ⁵⁴ - (wherein R ⁵³ is an alkenyl group or an aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a carbon number of 1~ a linear or branched alkyl group of 5, wherein n is 0, and Y ¹ is an alkyl group having 1 to 4 carbon atoms which may be substituted by fluorine. The photoresist composition according to claim 1, wherein the substrate component (A) is a substrate component which increases solubility in an alkali developer via an action of an acid. The photoresist composition of claim 2, wherein the substrate component (A) is added to the alkali developer by the action of an acid A soluble resin component (A1) which is a structural unit (a1) derived from an acrylate having an acid dissociable dissolution inhibiting group. The photoresist composition of claim 3, wherein the resin component (A1) further has a structural unit (a2) derived from an acrylate containing a lactone-containing cyclic group. The photoresist composition according to claim 3, wherein the resin component (A1) further has a structural unit (a3) derived from an acrylate containing a polar group-containing aliphatic hydrocarbon group. The photoresist composition of claim 4, wherein the resin component (A1) further has a structural unit (a3) derived from an acrylate containing a polar group-containing aliphatic hydrocarbon group. The photoresist composition of claim 1, wherein the nitrogen-containing organic compound (D) is contained. A method for forming a photoresist pattern, comprising the step of forming a photoresist film on a support by using the photoresist composition according to any one of claims 1 to 7 to expose the photoresist film And a step of alkali developing the aforementioned photoresist film to form a photoresist pattern. a compound represented by the following formula (b1-1), Wherein R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and when n1 is 1, R ¹ and R ³ may be bonded to each other, and The carbon atom of R ¹ bond and the carbon atom of R ³ bond form a ring of 3 to 7 member ring structure at the same time, and A is a ring of 3 to 7 ring structure which can form a ring with the A bond. The valence group, the ring may have a substituent, and R ² is a group represented by R ⁵³ -R ⁵⁴ - (wherein R ⁵³ is an alkenyl group or an aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a carbon number of 1~ a linear or branched alkyl group of 5, wherein n is 0, and Y ¹ is an alkyl group having 1 to 4 carbon atoms which may be substituted by fluorine. A method for producing a compound represented by the formula (B1-1-1), which comprises a compound represented by the following formula (I) and a compound represented by the following formula (II); a step of reacting a copper catalyst to obtain a compound represented by the following formula (b1-1-1), Wherein A is a divalent group which can form a ring of a 3 to 7 member ring structure simultaneously with the sulfur atom bonded to the A bond, the ring may have a substituent, and R ² is an aromatic group which may have a substituent a linear or branched alkyl group having 1 to 10 carbon atoms which may have an alkoxy group, a chlorine atom, a bromine atom, an iodine atom or a hydroxyl group as a substituent, or a carbon number which may have a substituent 2~ a linear or branched alkenyl group of 10, n is 0, Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine, and R ¹ is an independently substituted aryl group or an alkane. base〕. a compound represented by the formula (I), [wherein R ² is an aromatic group which may have a substituent, and may have a linear or branched carbon number of 1 to 10 which may have an alkoxy group as a substituent, a chlorine atom, a bromine atom, an iodine atom or a hydroxyl group; An alkyl group, or a linear or branched alkenyl group having 2 to 10 carbon atoms which may have a substituent, n is 0, and Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine. R ¹ is an aryl group or an alkyl group which may independently have a substituent. A method for producing a compound represented by the formula (I), which comprises reacting a compound represented by the following formula (I-1) with a compound represented by the following formula (I-2) a step of producing a compound represented by the following formula (I), [wherein R ² is an aromatic group which may have a substituent, and may have a linear or branched carbon number of 1 to 10 which may have an alkoxy group as a substituent, a chlorine atom, a bromine atom, an iodine atom or a hydroxyl group; An alkyl group, or a linear or branched alkenyl group having 2 to 10 carbon atoms which may have a substituent, n is 0, and Y ¹ is an alkylene group having 1 to 4 carbon atoms which may be substituted by fluorine. M ⁺ is an alkali metal ion, R ¹ is an independently aryl or alkyl group which may have a substituent, and R ⁷ is an alkyl group or a fluorinated alkyl group. An acid generator characterized by being formed by a compound of claim 9 of the patent application.