TW201409168A - Radiation-sensitive resin composition, resist pattern forming method, radiation-sensitive acid generator, compound and method for producing compound - Google Patents

Abstract

The present invention is a radiation-sensitive resin composition, which contains an acid-cleavable group-containing polymer, a radiation-sensitive acid generator and a solvent, and wherein the radiation-sensitive acid generator contains a compound represented by formula (1). In formula (1), L represents at least one moiety that is selected from the group consisting of -COO-*, -SO2O-, -CONRA-, -O- and -S-, or a single bond; and * represents a binding site bonded with G. In formula (1), it is preferable that: L represents at least one moiety that is selected from the group consisting of -COO-*, -SO2O-, -CONRA-, -O- and -S-; RA represents a hydrogen atom or a monovalent hydrocarbon group having 1-20 carbon atoms; R1 represents a substituted or unsubstituted alkanediyl group having 1-10 carbon atoms, wherein a fluorine atom is not bonded to the carbon atom that is adjacent to SO3 -; and G represents a group that contains an alicyclic structure having 3-30 carbon atoms.

Description

Radiation-sensitive resin composition, resist pattern forming method, radiation-sensitive acid generator, compound and compound manufacturing method

The present invention relates to a radiation sensitive resin composition, a resist pattern forming method, a radiation sensitive acid generator, a compound, and a method for producing the compound.

The radiation-sensitive resin composition used in the microfabrication by lithography is irradiated by a far-ultraviolet light such as ArF excimer laser light, KrF excimer laser light, or a charged particle beam such as an electron beam. An acid is generated in the exposed portion, and a chemical reaction between the exposed portion and the unexposed portion causes a difference in the dissolution rate of the developing solution with the acid as a catalyst to form a resist pattern on the substrate.

With regard to the radiation-sensitive resin composition, it is required to improve the resolution and the rectangular shape of the cross-sectional shape of the resist pattern as the processing technique is refined. In response to this request, the types, molecular structures, and molecular structures of the polymers, acid generators, and other components used in the composition have been reviewed, and the combinations thereof have been reviewed in detail (see Japanese Patent Laid-Open No. Hei 11-125907, Japanese Patent Application No. Hei 8-146610). Bulletin and Japan Unexamined 2000-298347 Newspaper).

Among them, the resolution of the resist pattern or the cross-sectional shape of the cross-sectional shape has not been sufficiently satisfactory. Further, it is also required to exhibit excellent line width roughness (LWR) performance of the line width deviation of the resist pattern, and further increase the depth of focus in order to improve process stability. However, the above-mentioned past radiation-sensitive resin composition cannot satisfy these requirements.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 11-125907

[Patent Document 2] Japanese Patent Laid-Open No. Hei 8-146610

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2000-298347

The present invention has been made in view of the above circumstances, and an object thereof is to provide a radiation-sensitive resin composition having excellent LWR performance, resolution, rectangular shape of a cross-sectional shape, and excellent depth of focus.

The invention for solving the above problems is a radiation-sensitive resin composition containing an acid-dissociable group-containing polymer (hereinafter also referred to as "[A] polymer") and a radiation-sensitive acid generator (hereinafter also referred to as The "[B] acid generator") and the solvent (hereinafter also referred to as "[C] solvent"), the radiation-sensitive acid generator includes a compound represented by the following formula (1), [Chem. 1] GLR ¹ -SO ₃ ^- M ⁺ (1) (In the formula (1), L is at least selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S- One or a single bond, R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, * represents a bonding site with G, and L is composed of -COO-*, -SO ₂ O-, -CONR ^A -, - When at least one selected from the group consisting of O- and -S-, R ¹ is a substituted or unsubstituted carbon number of 1 to 10 adjacent to an unbonded fluorine atom on a carbon atom of SO ₃ ^- G, a group having an alicyclic structure having a carbon number of 3 to 30, a base having an aromatic ring structure of 6 to 30 carbon atoms, a heterocyclic structure having a carbon number of 3 to 30, or a carbon number of 2 to 20 -NR ^B R ^C group, when L is a single bond, R ¹ is a single bond or a bond to a fluorine atom adjacent to a carbon atom of SO ₃ ^- Substituted or unsubstituted alkanediyl having 1 to 10 carbon atoms, G is a polycyclic alicyclic hydrocarbon group having 7 to 30 carbon atoms or a NR ^B R ^C group having 2 to 20 carbon atoms, R ^B and R ^{C is} independently an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms, or a ring number of 3 to 20 which is bonded to the nitrogen atoms bonded to the groups. In the ring structure, M ⁺ is a monovalent radiation-decomposable cation cation).

The resist pattern forming method of the present invention has the steps of: forming a resist film using the radiation sensitive resin composition, exposing the resist film, and developing the exposed resist film The steps.

Sense of the present invention radiation-sensitive acid generator based compound represented by the following formula of (1) the composition of [2] GLR ¹ -SO ₃ ^- in the M ⁺ (1) (Formula (1), L by -COO At least one or a single bond selected from the group consisting of -*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, and R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. * indicates a bonding site with G, and L is at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, and R ¹ is adjacent a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms which is not bonded to a fluorine atom at a carbon atom of SO ₃ ^- , and a carbon group having a carbon number of 3 to 30 and having a carbon number of 6 a base of an aromatic ring structure of ~30, a group of a heterocyclic structure having a carbon number of 3 to 30 or a group of -NR ^B R ^{C having a} carbon number of 2 to 20, and when L is a single bond, R ¹ is a single bond or adjacency a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms which is not bonded to a fluorine atom at a carbon atom of SO ₃ ^- , and G is an alicyclic hydrocarbon group having a carbon number of 7 to 30 or a carbon number 2 to 20 -NR ^B R ^C group, R ^B and R ^{C are} each independently a C 1-10 alkyl group or a C 3-10 cycloalkyl group, or indicate that the groups are bonded to each other Bonded The number of ring membered ring structure of 3 to 20 constitutes together with the atoms, M ⁺ is a monovalent cation of radiation decomposable).

The compound of the present invention is represented by the following formula (1) ^: G ₃ ¹ -SO ₃ ^- M ⁺ (1) (in the formula (1), L is -COO-*, -SO ₂ O-, - At least one or a single bond selected from the group consisting of CONR ^A -, -O-, and -S-, and R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and * represents a bonding site with G, L When at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, R ¹ is a bond adjacent to a carbon atom of SO ₃ ^- a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms, a carbon atom having a carbon number of 3 to 30, a base having an aromatic ring structure having a carbon number of 6 to 30, and a a group having a carbon number of 3 to 30 or a group having a carbon number of 2 to 20 -NR ^B R ^{C. When} L is a single bond, R ¹ is a single bond or a bond adjacent to a carbon atom of SO ₃ ^- a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms, a carbon atom of 7 to 30 or a NR ^B R ^{C having a} carbon number of 2 to 20 The radicals, R ^B and R ^{C are} each independently a C 1-10 alkyl group or a C 3-10 cycloalkyl group, or a ring member which is bonded to the bonded nitrogen atoms. Number 3~20 ring Made, M ⁺ is a monovalent cation of radiation decomposable).

The method for producing a compound of the present invention is a method for producing a compound represented by the following formula (1) having the following steps: reacting an organic halide represented by the following formula (ia) with a sulfite represented by E ₂ SO ₃ a step of obtaining a sulfonate represented by the following formula (ib), and a step of reacting the above sulfonate with an onium salt represented by MY, (In the formulas (ia), (ib) and (1), L is at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S- Or a single bond, R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, * represents a bonding site with G, and L is a group of -COO-*, -SO ₂ O-, -CONR ^A -, -O When at least one selected from the group consisting of - and -S-, R ¹ is a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms adjacent to an unbonded fluorine atom on a carbon atom of SO ₃ ^- , G is a base of an alicyclic structure having a carbon number of 3 to 30, a base of an aromatic ring having a carbon number of 6 to 30, a base of a heterocyclic structure having a carbon number of 3 to 30, or a carbon number of 2 to 20 - NR ^B R ^C of the group, when L is a single bond, R ¹ is a single bond or adjacent to the SO ₃ ^- unbound by the junction of the fluorine atom on the carbon atom of a substituted or unsubstituted alkanediyl group having a carbon number of 1 to 10 , G is an alicyclic hydrocarbon group having a carbon number of 7 to 30 or a NR ^B R ^C group having a carbon number of 2 to 20, and R ^B and R ^{C are} each independently an alkyl group having 1 to 10 carbon atoms or carbon. a cycloalkyl group of 3 to 10, or a ring structure of 3 to 20 ring members which are bonded to the nitrogen atoms bonded to the groups, X is a halogen atom, and E ⁺ is an alkali metal ion. M ⁺ is a monovalent radiation Decomposable cation, Y ^- is a monovalent anion).

Here, the "organic group" means a group containing at least one carbon atom.

According to the radiation sensitive resin composition and the resist pattern forming method of the present invention, a wide focus depth can be exhibited, and a resist pattern having a small LWR, a high resolution, and a rectangular shape with a cross-sectional shape can be formed. The radiation-sensitive acid generator of the present invention can be preferably used as a component of the radiation-sensitive resin composition. The compound of the present invention can be preferably used as the radiation-sensitive acid generator. According to the method for producing a compound of the present invention, the compound can be produced simply and in good yield. According to this, these can be preferably used in a manufacturing process or the like in a semiconductor device which is further miniaturized in the future.

<Inductive Radiation Resin Composition>

The radiation sensitive resin composition contains a [A] polymer, a [B] acid generator, and a [C] solvent. Further, the radiation sensitive resin composition may contain a radioactive acid generator other than the [D][B] radiation-sensitive acid generator (hereinafter also referred to as "[D] other acid generator"), [E The compound containing a nitrogen atom and/or the polymer of [F] fluorine atom may be contained as a preferable component, and may contain other arbitrary components within the range which does not impair the effect of this invention. Hereinafter, each component will be described.

<[A] Polymer>

[A] The polymer is a polymer containing an acid dissociable group. According to the radiation sensitive resin composition, the acid dissociable group of the [A] polymer in the exposed portion is dissociated by irradiation of radiation, and the solubility of the exposed portion and the unexposed portion to the developing solution is different. A resist pattern is formed. The "acid dissociable group" means a group which substitutes a hydrogen atom of a carboxyl group, a hydroxyl group or the like and which is dissociated by the action of an acid. The [A] polymer is not particularly limited as long as it contains an acid-dissociable group, and may be contained in a main chain, a side chain, a terminal or the like. [A] The polymer may have a structural unit (II) represented by the following formula (3), which will be described later, in addition to a structural unit containing an acid-dissociable group (hereinafter also referred to as "structural unit (I)"). The structural unit (III) represented by the following formula (4), the structural unit (IV) containing a guanamine group, and other structural units other than the above structural units (I) to (IV). The [A] polymer may have one or two or more structural units. Hereinafter, for each structural unit Description.

[structural unit (I)]

The structural unit (I) is a structural unit containing an acid-dissociable group. The structural unit (I) is, for example, a structural unit represented by the following formula (2-1) (hereinafter also referred to as "structural unit (I-1)"), and a structural unit represented by the following formula (2-2) (hereinafter) Also known as "structural unit (I-2)").

In the above formula (2-1), R ² is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. Y ¹ is a monovalent acid dissociable group.

In the above formula (2-2), R ³ is a hydrogen atom or a methyl group. Y ² is a monovalent acid dissociable group.

From the viewpoint of obtaining the copolymerizability of the monomer of the structural unit (I-1), R ² is preferably a hydrogen atom or a methyl group, more preferably a methyl group.

The monovalent acid dissociable group represented by the above Y ¹ is preferably a group represented by the following formula (Y-1).

In the above formula (Y-1), R ^e1 is a monovalent chain hydrocarbon group having 1 to 10 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms. R ^e2 and R ^e3 each independently represent a monovalent chain hydrocarbon group having 1 to 10 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or the groups are bonded to each other to bond with the carbon atoms bonded thereto. The ring has a carbon number of 3 to 20 alicyclic structure.

The monovalent chain hydrocarbon group having 1 to 10 carbon atoms represented by the above R ^e1 , R ^e2 and R ^e3 is exemplified by methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and An alkyl group such as dibutyl, tert-butyl or n-pentyl; an alkenyl group such as a vinyl group, a propenyl group, a butenyl group or a pentenyl group; an alkynyl group such as an ethynyl group, a propynyl group, a butynyl group or a pentynyl group; Wait.

Among these, an alkyl group is preferred, and an alkyl group having 1 to 4 carbon atoms is more preferred, and more preferably a methyl group, an ethyl group or an isopropyl group, and most preferably an ethyl group.

The monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms represented by the above R ^e1 , R ^e2 and R ^e3 is exemplified by a monocyclic ring such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group or a cyclooctyl group. a cycloalkyl group; a polycyclic cycloalkyl group such as a norbornyl group, an adamantyl group, a tricyclodecanyl group or a tetracyclododecyl group; a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, a cyclohexenyl group, etc. a monocyclic cycloalkenyl group; a polycyclic cycloalkenyl group such as a norbornene group or a tricyclodecenyl group; and the like.

Among these, a monocyclic cycloalkyl group or a polycyclic cycloalkyl group is preferred, and more preferably a cyclopentyl group, a cyclohexyl group, a norbornyl group or an adamantyl group.

The alicyclic structure in which the above-mentioned groups are bonded to each other and the carbon atoms to be bonded together constitutes a ring carbon number of 3 to 20 is exemplified by a cyclopropane structure, a cyclobutane structure, a cyclopentane structure, and a cyclohexane. a monocyclic naphthenic structure such as an alkane structure or a cyclooctane structure; a polycyclic naphthenic structure such as a norbornane structure, an adamantane structure, a tricyclodecane structure or a tetracyclododecane structure; a cyclopropene structure; a monocyclic cycloolefin structure such as an ene structure, a cyclopentene structure, a cyclohexene structure, or a cyclooctene structure; a polycyclic cycloolefin structure such as a norbornene structure, a tricyclic terpene structure, or a tetracyclododecene structure; Wait.

Among these, a monocyclic naphthenic structure and a polycyclic naphthenic structure are preferred, and a cycloalkane structure having a single ring of 5 to 8 carbon atoms and a cycloalkane having a polystyrene having a carbon number of 7 to 12 are more preferable. Further, it is preferably a cyclopentane structure, a cyclohexane structure, a cyclooctane structure, a norbornane structure, or an adamantane structure, and is preferably a cyclopentane structure or an adamantane structure.

The group represented by (Y-1) above preferably represents a ring-shaped hydrocarbon group in which R ^e1 is a monovalent chain hydrocarbon group having 1 to 10 carbon atoms, and R ^e2 and R ^e3 are bonded to each other and the carbon atoms bonded thereto. The alicyclic structure of 3 to 20 preferably indicates that R ^e1 is an alkyl group having 1 to 10 carbon atoms, and R ^e2 and R ^e3 are bonded to each other to form a ring carbon number of 3 to 20 together with the carbon atoms bonded thereto. The naphthenic structure further preferably represents that R ^e1 is an alkyl group having 1 to 4 carbon atoms, and R ^e2 and R ^e3 are bonded to each other to form a ring of 5 to 8 ring carbon atoms together with the carbon atoms bonded thereto. The cycloalkane structure or the polycyclic naphthenic structure having a ring carbon number of 7 to 12 is preferably 1-ethyl-1-cyclopentyl or 2-ethyl-2-adamantyl.

The above R ³ is preferably a hydrogen atom from the viewpoint of obtaining copolymerization properties of the monomer of the structural unit (I-2).

The monovalent acid dissociable group represented by the above Y ² is preferably a group represented by the following formula (Y-2).

In the above formula (Y-2), R ^e4 , R ^e5 and R ^{e6 are} each independently a hydrogen atom, a monovalent chain hydrocarbon group having 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, and a carbon number. An oxy chain hydrocarbon group of 1 to 20 or an oxyalicyclic hydrocarbon group having 1 to 20 carbon atoms. However, there is no case where R ^e4 , R ^e5 and R ^{e6 are} both hydrogen atoms.

The monovalent chain hydrocarbon group having 1 to 20 carbon atoms represented by the above R ^e4 , R ^e5 and R ^e6 is exemplified by a methyl group, an ethyl group, a n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and the like. An alkyl group such as dibutyl, tert-butyl or n-pentyl; an alkenyl group such as a vinyl group, a propenyl group, a butenyl group or a pentenyl group; an alkynyl group such as an ethynyl group, a propynyl group, a butynyl group or a pentynyl group; Wait.

Among these, an alkyl group is preferred, and an alkyl group having 1 to 4 carbon atoms is more preferred, and more preferably a methyl group, an ethyl group or a n-propyl group, and most preferably a methyl group.

The monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms represented by the above R ^e4 , R ^e5 and R ^e6 is, for example, the same as those exemplified as the above R ^e1 , R ^e2 and R ^e3 .

Among these, a monocyclic cycloalkyl group or a polycyclic cycloalkyl group is preferred, and more preferably a cyclopentyl group, a cyclohexyl group, a norbornyl group or an adamantyl group.

The oxy chain hydrocarbon group having 1 to 20 carbon atoms represented by the above R ^e4 , R ^e5 and R ^e6 is exemplified by a methoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group, or the like. Alkoxy group such as isobutoxy group, second butoxy group, third butoxy group or n-pentyloxy group; alkenyloxy group such as ethyleneoxy group, propyleneoxy group, butenyloxy group or pentenyloxy group; acetylene oxide An alkynyloxy group such as a propargyloxy group, a butynyloxy group or a pentynyloxy group.

Among these, an alkoxy group is preferred, an alkoxy group having 1 to 4 carbon atoms is more preferred, and a methoxy group, an ethoxy group or a n-propoxy group is more preferred.

The monovalent oxyalicyclic hydrocarbon group having 3 to 20 carbon atoms represented by the above R ^e4 , R ^e5 and R ^e6 is exemplified by a cyclopropoxy group, a cyclobutoxy group, a pentyloxy group, a cyclohexyloxy group, and the like. a monocyclic cycloalkoxy group such as a cyclooctyloxy group; a polycyclic cycloalkoxy group such as a norbornyloxy group, an adamantyloxy group, a tricyclodecyloxy group or a tetracyclododecyloxy group; a cyclopropenyloxy group; a monocyclic cycloalkenyloxy group such as a cyclobutenyloxy group, a cyclopentenyloxy group or a cyclohexenyloxy group; a polycyclic cycloalkenyloxy group such as a norborneneoxy group or a tricyclodecenyloxy group;

Among these, a monocyclic cycloalkoxy group or a polycyclic cycloalkoxy group is preferred, and more preferably a cyclopentyloxy group, a cyclohexyloxy group, a norbornyloxy group or an adamantyloxy group.

The group represented by the above formula (Y-2) is preferably R ^e4, R ^e5 and R ^e6 is a monovalent hydrocarbon group of chain, R ^e4 and R ^e5 is a monovalent hydrocarbon group of chain 1 is oxygen and R ^e6 price of the a group of a chain-like hydrocarbon group, R ^e4 is a monovalent chain hydrocarbon group, and R ^e5 and R ^e6 are a group of a monovalent oxy chain hydrocarbon group, and more preferably R ^e4 , R ^e5 and R ^e6 are an alkyl group. , R ^e4 and R ^e5 are alkyl and R ^e6 is alkoxy group, R ^e4 is alkyl and R ^e5 and R ^e6 are alkoxy groups, more preferably R ^e4 , R ^e5 and R ^e6 are alkane The base group is preferably a third butyl group, a third pentyl group, a third hexyl group or a third heptyl group.

The structural unit (I) is exemplified by, for example, the structural unit (I-1) being a structural unit represented by the following formulas (2-1-1) to (2-1-7); and the structural unit (I-2) is The structural unit represented by the following formula (2-2-1) to (2-2-3).

In the above formulae (2-1-1) to (2-1-7), R ² has the same meaning as the above formula (2-1). R ^e1 , R ^e2 and R ^{e3 are} synonymous with the above formula (Y-1). r is independently an integer from 1 to 3.

In the above formulas (2-2-1) to (2-2-3), R ³ has the same meaning as the above formula (2-2).

The structural unit (I) is preferably a structural unit (I-1), more preferably a structural unit represented by the above formula (2-1-2), and a structural unit represented by the above formula (2-1-3). More preferably a base containing cyclopentane, containing gold The base of the cycloalkane structure is preferably a structural unit derived from 1-ethyl-1-cyclopentyl (meth)acrylate and a structural unit derived from 2-ethyl-2-adamantyl (meth)acrylate. .

The content ratio of the structural unit (I) is preferably from 10 mol% to 90 mol%, more preferably from 20 mol% to 70 mol%, and more preferably all structural units constituting the [A] polymer. It is preferably 30% by mole to 60% by mole, preferably 40% by mole to 60% by mole. By setting the content ratio of the structural unit (I) to the above range, the LWR performance, the resolution, the squareness of the cross-sectional shape, and the depth of focus of the radiation-sensitive resin composition can be improved.

[structural unit (II)]

The structural unit (II) is a structural unit represented by the following formula (3-1) (hereinafter also referred to as "structural unit (II-1)") and a structural unit represented by the following formula (3-2) (hereinafter also At least one selected from the group consisting of "structural unit (II-2)"). By making the [A] polymer have the structural unit (II), the dispersibility of the [B] acid generator in the [A] polymer can be improved. As a result, the LWR performance, the resolution, the squareness of the cross-sectional shape, and the depth of focus of the radiation-sensitive resin composition can be improved. Further, the adhesion of the resist pattern formed of the radiation-sensitive resin composition to the substrate can be improved.

In the above formula (3-1), R ⁴ is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. E ¹ is a single bond, -CO-O-, -CO-NH- or -CO-O-(CH ₂ ) _i -CO-O, and i is an integer of 1 to 6. R ^{5 is a group which is} non-acid dissociable and which contains a polar group.

In the above formula (3-2), R ^4' is a hydrogen atom or a methyl group. R ^a and R ^{b are} each independently a hydrogen atom, a fluorine atom, a hydroxyl group or a monovalent organic group. s is an integer from 1 to 3. When s is 2 or more, the plurality of R ^a and R ^b may be the same or different. R ^5a and R ^{5b are} each independently a hydrogen atom, a fluorine atom, a hydroxyl group or a monovalent organic group.

In the structural unit (II-1), the above R ⁴ is preferably a hydrogen atom or a methyl group from the viewpoint of obtaining the copolymerizability of the monomer of the structural unit (II-1), and more preferably a methyl group.

As for the above E ¹ , from the viewpoint of obtaining the copolymerizability of the monomer of the structural unit (II-1), -CO-O- is preferable.

The polar group in the non-acid dissociable and polar group-containing group represented by the above R ⁵ is exemplified by a monovalent group (a) such as a hydroxyl group, a carboxyl group, a cyano group, a sulfo group, a decyl group or an amine group; a carbonyl group, -O -, -S-, -NR'-, a combination of these two-valent bases (b), and the like. R' is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms.

The non-acid dissociable and polar group-containing group represented by the above R ⁵ is, for example, a group in which one or all of the hydrogen atoms of the monovalent hydrocarbon group having 1 to 20 carbon atoms are substituted with the above-mentioned monovalent group (a). One or all of the hydrogen atoms of the monovalent hydrocarbon group having a carbon number of 1 to 20 and a part or all of the carbon-carbon containing the above-mentioned divalent group (b) and the monovalent hydrocarbon group having 1 to 20 carbon atoms The group of the monovalent (a) is substituted and the base of the above-mentioned divalent group (b) or the like is contained between some or all of the carbon-carbon.

The monovalent hydrocarbon group having 1 to 20 carbon atoms is, for example, a monovalent chain hydrocarbon group having 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and the like. .

The above-mentioned monovalent chain hydrocarbon group having 1 to 20 carbon atoms is exemplified by the same as those exemplified as R ^e4 , R ^e5 and R ^e6 in the above formula (2-2).

The above-mentioned monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms is exemplified by the same groups as those exemplified as R ^e1 , R ^e2 and R ^e3 in the above formula (2-1).

The above-mentioned monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms is exemplified by an aryl group such as a phenyl group, a tolyl group, a xylyl group, a mesityl group, a naphthyl group, a methylnaphthyl group, an anthracenyl group or a methyl fluorenyl group; An aralkyl group such as a benzyl group, a phenethyl group, a naphthylmethyl group or a fluorenylmethyl group.

R ^{5 is} exemplified by a group having a lactone structure, a group having a cyclic carbonate structure, a group having a sultone structure, a group having a hydroxyl group, and the like.

The above-mentioned group having a lactone structure is exemplified by, for example, a butyrolactone group, a norbornyl lactone group, a 5-oxo-4-oxatricyclo[4.3.1.1 ^3,8 ]undecyl group, and the like.

The group having a cyclic carbonate structure is exemplified by, for example, an ethyl carbonate methyl group.

The group having a sultone structure is exemplified by a sultone structure such as a propane sultone group or a norbornane sultone group.

The group having a hydroxyl group is exemplified by, for example, a hydroxyadamantyl group, a dihydroxyadamantyl group, a trihydroxyadamantyl group, a hydroxyethyl group or the like.

In the structural unit (II-2), the above R ^{4 '} is preferably a hydrogen atom from the viewpoint of obtaining the copolymerizability of the monomer of the structural unit (II-2).

The monovalent organic group represented by the above R ^a , R ^b , R ^5a and R ^5b is, for example, a monovalent chain hydrocarbon group having 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, and a carbon number of 6 a monovalent aromatic hydrocarbon group of ~20, a group in which one or all of the hydrogen atoms of the groups are substituted with a substituent, and the carbon-carbon of the groups contains -CO-, -CS-, -O-, - S- or -NR"-, or a combination of two or more of these.

s is preferably 1 or 2, more preferably 1.

The structural unit (II) is, for example, the structural unit (II-1) is a structural unit represented by the following formulas (3-1-1) to (3-1-13); and the structural unit (II-2) is as follows. The structural unit represented by the formulas (3-2-1) and (3-2-2).

In the above formulas (3-1-1) to (3-1-13), R ⁴ has the same meaning as the above formula (3-1).

In the above formulae (3-2-1) and (3-2-2), R ^4' is synonymous with the above formula (3-2).

Among these, it is preferred to use the above formulas (3-1-1) to (3-1-4), (3-1-8), (3-1-12), (3-1-13), The structural unit represented by (3-2-1) and (3-2-2) is more preferably a structural unit represented by the above formula (3-2).

The content ratio of the structural unit (II) is preferably from 0 mol% to 90 mol%, more preferably from 20 mol% to 70 mol%, and more preferably to all structural units constituting the [A] polymer. Good for 30%%~60% by mole. By making the content ratio of the structural unit (II) in the above range, the dispersibility of the [B] acid generator in the [A] polymer can be further improved, and as a result, the LWR property of the radiation sensitive resin composition can be further improved. Performance.

[structural unit (III)]

The structural unit (III) is a structural unit represented by the following formula (4). When KrF excimer laser light, EUV, electron beam, or the like is used as the radiation to be irradiated, the radiation sensitive linear resin composition can improve the sensitivity by making the [A] polymer have the structural unit (III).

In the above formula (4), R ⁶ is a hydrogen atom or a methyl group, R ⁷ is a monovalent organic group having 1 to 20 carbon atoms, p is an integer of 0 to 3, and when R ⁷ is plural, plural R ⁷ may be used. The same or different, q is an integer from 1 to 3, but p and q satisfy p+q≦5.

The above R ⁶ is preferably a hydrogen atom from the viewpoint of obtaining the copolymerizability of the monomer of the structural unit (III).

The monovalent organic group having 1 to 20 carbon atoms represented by the above R ⁷ is, for example, a monovalent chain hydrocarbon group having 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, and a carbon number of 6 to 20 a monovalent aromatic hydrocarbon group, a group in which one or all of the hydrogen atoms of the groups have a substituent, the carbon-carbon of the groups contains -CO-, -CS-, -O-, -S- or -NR"-, or a group in which two or more of these are combined.

Among these, a monovalent chain hydrocarbon group is preferred, and an alkyl group is more preferred, and a methyl group is more preferred.

The above p is preferably an integer of 0 to 2, more preferably 0 or 1, and more preferably 0.

The above q is preferably 1 or 2, more preferably 1.

The structural unit (III) is listed as follows (4-1)~ (4-4) indicates the structural unit and the like.

In the above formulae (4-1) to (4-4), R ⁶ has the same meaning as the above formula (4).

Among these, the structural unit represented by the above formulas (4-1) and (4-2) is preferable, and the structural unit represented by the above formula (4-1) is more preferable.

The content ratio of the structural unit (III) is preferably from 0 mol% to 90 mol%, more preferably from 30 mol% to 80 mol%, and more preferably all structural units constituting the [A] polymer. It is preferably 50% by mole to 755% by mole. By setting the content ratio of the structural unit (III) to the above range, the sensitivity of the radiation sensitive resin composition can be further improved.

Further, the structural unit (III) can be formed by polymerizing a monomer in which a hydrogen atom of the -OH group of the hydroxystyrene is substituted with a third butyl group or the like, and then subjecting the obtained polymer to a hydrolysis reaction in the presence of an amine.

[structural unit (IV)]

The structural unit (IV) is a structural unit represented by the following formula (5). [A] The polymer can adjust the solubility to the developing solution by having the structural unit (IV) while appropriately controlling the acid diffusion in the resist film. As a result, the lithographic performance of the radiation sensitive resin composition can be further improved.

In the above formula (5), R ⁸ is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R ⁹ and R ^{10 are} each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, or a ring structure of 3 to 20 ring members which are bonded to each other and a nitrogen atom bonded to the groups.

From the viewpoint of obtaining the copolymerizability of the monomer of the structural unit (IV), R ⁸ is preferably a hydrogen atom or a methyl group, more preferably a methyl group.

The hydrocarbon group having 1 to 20 carbon atoms represented by the above R ⁹ and R ¹⁰ is, for example, the same as those exemplified as the hydrocarbon group having 1 to 20 carbon atoms in R ⁵ of the above formula (3).

Among these, an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group.

The ring structure in which the above-mentioned groups are bonded to each other and the nitrogen atom to which the groups are bonded together is represented by a ring structure of 3 to 20, for example, a nitrogen heterocyclopentane structure (pyrrolidine structure), azacyclohexane Alkane structure (piperidine structure), azepanic structure, azacyclooctane structure, etc. Create and so on.

Among these, the azacyclopentane structure and the azacyclohexane structure are preferred, and more preferably the azacyclohexane structure.

The structural unit (IV) is exemplified by a structural unit represented by the following formulas (5-1) to (5-2).

In the above formulae (5-1) to (5-4), R ⁸ has the same meaning as the above formula (5).

Among these, the structural unit represented by the above formula (5-1) to (5-3) is preferable, and the structural unit represented by the above formula (5-1) is more preferable.

The content ratio of the structural unit (IV) is preferably from 0 mol% to 30 mol%, more preferably from 1 mol% to 20 mol%, and more preferably relative to all structural units constituting the [A] polymer. It is 5 mol%~15 mol%. By setting the content ratio of the structural unit (IV) to the above range, the lithographic performance of the radiation sensitive resin composition can be further improved.

[Other construction units]

The [A] polymer may have other structural units other than the above structural units (I) to (IV). Other structural units are exemplified by, for example, a structural unit derived from a (meth) acrylate containing a non-dissociable monovalent alicyclic hydrocarbon group. The content ratio of the other structural unit is preferably 20 mol% or less, more preferably 10 mol% or less, based on the entire structural unit constituting the [A] polymer.

<[A] Synthesis Method of Polymer>

[A] The polymer can be synthesized according to a usual method such as radical polymerization. For example, (1) a method in which a solution containing a monomer and a radical initiator is added dropwise to a solution containing a reaction solvent or a monomer to carry out a polymerization reaction, and (2) a solution containing a monomer and a radical-containing solution are used. The solution of the initiator is added dropwise to the solution containing the reaction solvent or the monomer to carry out the polymerization reaction, and (3) the solution containing the respective monomers and the solution containing the radical initiator are separately added to the reaction. A method of performing a polymerization reaction in a solvent or a monomer solution, and (4) synthesizing a solution containing a monomer and a radical initiator in a solventless manner or a polymerization reaction in a reaction solvent.

Further, when the monomer solution is added dropwise to carry out the reaction, the amount of the monomer in the monomer solution to be added is preferably 30 mol% or more, more preferably 50 mol%, based on the total amount of the monomers used for the polymerization. More than %, and more preferably more than 70% by mole.

The reaction temperature in the methods may be appropriately determined depending on the type of the initiator. Usually 30 ° C ~ 150 ° C, preferably 40 ° C ~ 150 ° C, More preferably 50 ° C ~ 140 ° C. The dropwise addition time varies depending on the reaction temperature, the type of the initiator, the monomer to be reacted, and the like, but is usually 30 minutes to 8 hours, preferably 45 minutes to 6 hours, more preferably 1 hour to 5 hours. Further, the total reaction time including the dropping time is also different from the dropping time depending on the conditions, but it is usually from 30 minutes to 12 hours, preferably from 45 minutes to 12 hours, more preferably from 1 to 10 hours.

The radical initiator used in the above polymerization is exemplified by, for example, azobisisobutyronitrile (AIBN), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2 , 2'-azobis(2-cyclopropylpropionitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methyl An azo radical initiator such as dimethyl diacetate or dimethyl 2,2'-azobisisobutyrate; benzhydryl peroxide, tert-butyl hydroperoxide, cumene A peroxide-based radical polymerization initiator such as hydrogen peroxide. Among these, AIBN, 2,2'-azobis(2-methylpropionic acid) dimethyl ester is preferred. Further, the radical initiators may be used singly or in combination of two or more.

The reaction solvent is a solvent other than a solvent which inhibits polymerization (nitrobenzene having a polymerization inhibitory effect, a thiol compound having a chain transfer effect, etc.), and can be used as long as it can dissolve the solvent of the monomer. Listed as, for example, alcohols, ethers, ketones, guanamines, esters. Lactones, nitriles and mixed solvents thereof. These solvents may be used singly or in combination of two or more.

The polymer obtained by the polymerization is preferably recovered by a reprecipitation method. That is, after the completion of the polymerization reaction, the target polymer is recovered as a powder by pouring the polymerization liquid into a reprecipitation solvent. The reprecipitation solvent can be used singly or in combination of two or more kinds of alcohols or alkanes. And, in addition to the reprecipitation method, The polymer can also be recovered by removing a low molecular component such as a monomer or an oligomer by a liquid separation operation, a column operation, an ultrafiltration operation, or the like.

[A] Polymer The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) is preferably from 1,000 to 50,000, more preferably from 2,000 to 40,000, still more preferably from 3,000 to 30,000. , preferably 5,000~20,000. When the Mw of the polymer is less than the above lower limit, the heat resistance of the resist pattern formed of the radiation-sensitive resin composition may be lowered. When the Mw of the polymer exceeds the above upper limit, the developability of the radiation-sensitive resin composition may be lowered.

[A] The ratio of the Mw of the polymer to the number average molecular weight (Mw) in terms of polystyrene by GPC (Mw/Mn, dispersity) is preferably from 1 to 5, more preferably from 1 to 3, and further Good for 1~2.5.

The content of the low molecular weight portion (meaning that the molecular weight is less than 1,000) in the polymer is preferably 0.5% by mass or less, more preferably 0.3% by mass or less, still more preferably 0.1% by mass or less. By setting the content of the low molecular weight portion to the above range, the LWR performance and the like of the radiation sensitive resin composition can be further improved.

The content of the [A] polymer is preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 85% by mass or more based on the total solid content of the radiation sensitive resin composition.

<[B]acid generator>

The [B] acid generator contains a compound represented by the following formula (1) (hereinafter also referred to as "compound (1)"). The radiation-sensitive linear resin composition The [B] acid generator is excellent in RWR performance, resolution, cross-sectional shape, and depth of focus.

[15] GLR ¹ -SO ₃ ^- M ⁺ (1) In the above formula (1), L is composed of -COO-*, -SO ₂ O-, -CONR ^A -, -O- and -S- At least one or a single bond selected from the group, R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, * represents a bonding site with G, and L is a group of -COO-*, -SO ₂ O-, At least one selected from the group consisting of -CONR ^A -, -O-, and -S-, and R ¹ is a substituted or unsubstituted carbon number of an unbonded fluorine atom adjacent to a carbon atom of SO ₃ ^- ~10 alkanediyl, G is an alicyclic structure having a carbon number of 3 to 30, an aromatic ring structure having a carbon number of 6 to 30, a heterocyclic structure having a carbon number of 3 to 30, or a carbon Number of 2 to 20 -NR ^B R ^C , when L is a single bond, R ¹ is a single bond or a substituted or unsubstituted carbon number of an unbonded fluorine atom adjacent to a carbon atom of SO ₃ ^- ~10 alkanediyl, G is a polycyclic alicyclic hydrocarbon group having a carbon number of 7 to 30 or a NR ^B R ^C group having a carbon number of 2 to 20, and R ^B and R ^{C are} each independently a carbon number of 1~ An alkyl group of 10 or a cycloalkyl group having 3 to 10 carbon atoms, or a ring structure of 3 to 20 ring members which are bonded to the nitrogen atoms bonded to the groups, and M ⁺ is a monovalent structure. Radiation decomposing Child.

[B] The acid generator is a sulfonic acid compound by causing a proton to bond to -SO ₃ ^- of the compound (1) by irradiation with radiation.

[B] The acid generator has a structural unit (I-1) as an acid dissociable group in the [A] polymer, and a post-exposure bake (PEB) temperature is low when the resist pattern is formed (for example, 110 ° C or less) In the case where the acid is trapped in the unexposed portion, the acid capturing function is lost in the exposed portion. Accordingly, it is considered that the controllable acid does not diffuse to the unexposed portion.

Further, the [B] acid generator has a structural unit (I-1) as an acid dissociable group in the [A] polymer, and the PEB temperature is high (for example, 120 ° C or higher), or the [A] polymer has a structural unit. (I-2) When it is an acid dissociable group, it is considered that the acid dissociable group can be dissociated by using an acid generated from the [B] acid generator by irradiation of radiation as a catalyst.

Although the reason why the above-described effects are exhibited by including the [B] acid generator in the radiation-sensitive resin composition is not necessarily clear, it is presumed as follows. [B] The acid generator is a alicyclic or aromatic ring structure having a moderate polarity containing -COO-, -NR ^B R ^C or the like, or an alicyclic hydrocarbon group having a polycyclic ring. Thus, the [B] acid generator has a moderate polarity and volume, and as a result, the diffusion of the [B] acid generator and the acid produced by the [B] acid generator can be controlled to be moderate. According to this, according to the [B] acid generator, the LWR performance, the resolution, the squareness of the cross-sectional shape, and the depth of focus of the radiation-sensitive resin composition can be improved.

The monovalent hydrocarbon group having 1 to 20 carbon atoms represented by R ^{A in the} above -CONR ^A - is, for example, the same as those exemplified as R ⁹ and R ¹⁰ in the above formula (5) in the [A] polymer.

Among these, it is preferably an alkyl group, more preferably an alkyl group having 1 to 4 carbon atoms, and still more It is preferably methyl or ethyl.

The above R ^{A is} preferably a hydrogen atom.

The unsubstituted alkanediyl group having 1 to 10 carbon atoms which is not bonded to the fluorine atom on the carbon atom of the SO ₃ ^- represented by the above R ¹ is exemplified by, for example, methane diyl and 1,2-ethane diyl. , 1,3-propanediyl, 1,4-butanediyl, 1,5-pentanediyl, 1,6-hexanediyl, 1,7-heptanediyl, 1,8-octyl a linear alkanediyl group such as an alkanediyl group, a 1,9-nonanediyl group or a 1,10-decanediyl group; a 1,1-ethanediyl group, a 1,1-propanediyl group, a 1,2- a branched alkanediyl group such as a propanediyl group, a 1,2-butanediyl group, a 1,3-butanediyl group or a 1,4-pentanediyl group.

The substituent which may be substituted for a part or the whole of one of the hydrogen atoms of the above alkanediyl group is exemplified by a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, a hydroxyl group, a carboxyl group, an amine group, a cyano group, a nitro group or an alkane group. An oxy group, an alkoxycarbonyl group, a decyl group, a decyloxy group or the like. However, the fluorine atom as a substituent is not bonded to a carbon atom adjacent to SO ₃ ^- .

The above R ^{1 is} preferably an unsubstituted alkanediyl group, more preferably an unsubstituted and linear alkanediyl group, more preferably a 1,2-ethanediyl group or a 1,3-propanediyl group. , 1,4-butanediyl.

When the L system is at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, the carbon number represented by the above G is 3 to 30. The group of the alicyclic structure is exemplified by a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group; a polycyclic cycloalkyl group such as a norbornyl group or an adamantyl group; and the like.

The group of the aromatic ring structure having 6 to 30 carbon atoms represented by the above G is exemplified by an aryl group such as a phenyl group, a tolyl group, a xylyl group or a mesityl group; an aralkyl group such as a benzyl group or a phenethyl group; .

The group having a heterocyclic ring structure having 3 to 30 carbon atoms represented by the above G is, for example, an aliphatic heterocyclic group which is azacyclopentyl group, but a heterocyclohexyl group such as a heterocyclohexyl group; a butyrolactone group; a base having a lactone structure such as a borneol lactone group, a 5-oxo-4-oxatricyclo[4.3.1.1 ^3,8 ]undecyl group or the like; a carbonate ester methyl group having a cyclic carbonate The base of the structure; a base having a sultone structure such as a propane sultone group or a norbornane sultone group.

The alkyl group having 1 to 10 carbon atoms represented by the above R ^B and R ^C is exemplified by a methyl group, an ethyl group, a n-propyl group, an isopropyl group or the like.

The cycloalkyl group having 3 to 10 carbon atoms represented by the above R ^B and R ^C is exemplified by, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a norbornyl group, an adamantyl group, a tricyclic ring.癸基等.

The ring structure in which the above-mentioned groups are bonded to each other and the nitrogen atom to be bonded together constitutes a ring number of 3 to 20, which is represented by, for example, an azacyclohexane structure, an azacyclohexane structure, or azacyclononine. Azacycloalkane structure such as alkane structure.

R ^B and R ^C are preferably an alkyl group or an azacycloalkane structure in which R ^B and R ^C are bonded to each other, more preferably an alkyl group having 1 to 4 carbon atoms, or R ^B and R. ^C bonded to each other membered ring structure composed of aza-cycloalkyl of 3 to 8, and more preferably methyl or ethyl, or R ^B and R ^C represents a mutual binding azacyclopentane configuration or composed of azacyclohexyl Alkane structure.

The group of -NR ^B R ^C having a carbon number of 2 to 20 represented by the above G is exemplified by, for example, dimethylamino group, methylethylamino group, diethylamino group, di-n-propylamino group, and a dialkylamino group such as an isopropylamino group or a di-n-butylamino group; an N-azetidinyl group, an N-azetidinyl group, an N-azetidine group, an N-azacyclohexyl group, An N-azacycloalkyl group such as an N-azetidine group or the like.

Among these, a dimethylamino group, a diethylamino group, an N-azetidine group, and an N-azetidinyl group are preferred, and more preferably a dimethylamino group or an N-azacyclohexyl group. More preferably, it is an N-azacyclohexyl group.

When L is a single bond, the alicyclic hydrocarbon group having a polycyclic number of 7 to 30 represented by G is exemplified by a norbornyl group, an adamantyl group, a tricyclodecyl group, a tetracyclododecyl group or the like.

Among these, a norbornyl group, an adamantyl group is preferred, and an adamantyl group is more preferred.

The compound (I) is preferably a compound represented by the following formula (1-a) to (1-d).

In the above formula (1-a) to (1-d), G ¹ is a group represented by the following formula (g-1). G ² is a group represented by the following formula (g-2). X ¹ is -NR ^A -. X ² and X ^{3 are} each independently -O- or -NR ^A -. R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. R ¹ and M ^{+ are} synonymous with the above formula (1).

In the above formula (g-1), R ^b1 is an alkanediyl group having 1 to 6 carbon atoms. R ^b2 is a trivalent group or a nitrogen atom represented by R ^b4 C(-*) ₃ . * indicates the key combination. R ^b3 is a divalent group which binds to R ^b2 to form an alicyclic structure, an aromatic ring structure or a heterocyclic structure. R ^b4 is an alkyl group having 1 to 10 carbon atoms.

In the above formula (g-2), R ^c1 is a monovalent chain hydrocarbon group having 1 to 10 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms. R ^c2 and R ^{c3 are} each independently a chain hydrocarbon group having 1 to 10 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a combination of the groups and the carbon atoms bonded thereto. The alicyclic structure of the ring carbon number 3~20.

The monovalent radiation-decomposable phosphonium cation represented by the above M ⁺ is a cation which is decomposed by the action of radiation. A sulfonic acid is generated from the sulfonate anion of the compound (1) by a proton formed by decomposition of the ray-decomposable cation cation in the exposed portion. The monovalent radiation-decomposable phosphonium cation represented by the above M ⁺ is exemplified by radiation decomposability of elements such as S, I, O, N, P, Cl, Br, F, As, Se, Sn, Sb, Te, and Bi. Ruthenium cation. The cation containing S (sulfur) as an element is exemplified by a phosphonium cation, a tetrahydrothiophene cation, etc., and a cation containing I (iodine) as an element is exemplified by a phosphonium cation. Among these, a phosphonium cation represented by the following formula (M-1) and a phosphonium cation represented by the following formula (M-2) are preferred.

In the above formula (M-1), R ¹¹ , R ¹² and R ^{13 are} each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, substituted or unsubstituted. An aromatic hydrocarbon group having 6 to 12 carbon atoms, -SO ₂ -R ^D or -SO ₂ -R ^E , or a ring structure in which two or more of the groups are bonded to each other. R ^D and R ^{E are} each independently substituted or unsubstituted linear or branched alkyl having 1 to 12 carbon atoms, substituted or unsubstituted alicyclic hydrocarbon group having 5 to 25 carbon atoms or A substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. Each of k, m, and n is an integer of 0 to 5. When R ¹¹ to R ¹³ and R ^D and R ^{E are} each plural, the plural R ¹¹ to R ¹³ and R ^D and R ^E may be the same or different.

In the above formula (M-2), R ¹⁴ and R ^{15 are} each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, and a substituted or unsubstituted carbon number 6 An aromatic hydrocarbon group of ~12, -SO ₂ -R ^F or -SO ₂ -R ^G , or a ring structure in which two or more of these groups are bonded to each other. R ^F and R ^G are each independently a substituted or unsubstituted carbon atoms of the branched linear alkyl group of 1 to 12 or a substituted or unsubstituted alicyclic of 5 to 25 carbon atoms of the cyclic hydrocarbon group, or by A substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. Each of i and j is an integer of 0 to 5. When R ¹⁴ , R ¹⁵ , R ^F and R ^{G are} each plural, the plural R ¹⁴ , R ¹⁵ , R ^F and R ^G may be the same or different.

The unsubstituted linear alkyl group represented by the above R ¹¹ to R ¹⁵ is exemplified by a methyl group, an ethyl group, a n-propyl group, an n-butyl group or the like.

The unsubstituted branched alkyl group represented by the above R ¹¹ to R ¹⁵ is exemplified by isopropyl group, isobutyl group, second butyl group, tert-butyl group and the like.

The unsubstituted aromatic hydrocarbon group represented by the above R ¹¹ to R ¹⁵ is exemplified by an aryl group such as a phenyl group or a naphthyl group; an aralkyl group such as a benzyl group or a phenethyl group.

The substituent which may be substituted for the hydrogen atom of the above alkyl group and the aromatic hydrocarbon group is exemplified by a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an alkoxy group or an alkane group. An oxycarbonyl group, an alkoxycarbonyloxy group, a decyl group, a decyloxy group or the like.

Among these, a halogen atom is preferred, and a fluorine atom is more preferred.

The above R ¹¹ to R ^{15 are} preferably an unsubstituted linear or branched alkyl group, a fluorinated alkyl group, an unsubstituted monovalent aromatic hydrocarbon group, -OSO ₂ -R", -SO ₂ -R More preferably, it is a fluorinated alkyl group, an unsubstituted monovalent aromatic hydrocarbon group, and more preferably a fluorinated alkyl group. R" is an unsubstituted monovalent alicyclic hydrocarbon group or an unsubstituted monovalent aromatic hydrocarbon group.

The k, m and n in the above (M-1) are preferably an integer of 0 to 2, more preferably 0 or 1, more preferably 0.

i and j in the above (M-2) are preferably an integer of 0 to 2, more preferably 0 or 1, more preferably 0.

The compound (I) is exemplified by a compound represented by the following formula (1-1) to (1-25) (hereinafter also referred to as "compound (1-1) to (1-25)").

Among these, the compounds (1-1) to (1-17) are preferred.

The above compound (I) can be produced, for example, by the production method shown in the following reaction scheme by having the following steps (A) and (B).

(A) a step of reacting an organic compound represented by the following formula (ia) with a sulfite represented by E ₂ SO ₃ (E ⁺ ₂ SO ₃ ^2- ) to obtain a sulfonate represented by the following formula (ib) .

(B) a step of reacting the above sulfonate with an onium salt represented by MY(M ⁺ Y ^- ).

In the above formulas (ia), (ib) and (1), L is at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O- and -S- Or a single bond, R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, * represents a bonding site with G, and L is a group of -COO-*, -SO ₂ O-, -CONR ^A -, -O When at least one selected from the group consisting of - and -S-, R ¹ is a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms adjacent to an unbonded fluorine atom on a carbon atom of SO ₃ ^- , G is a base of an alicyclic structure having a carbon number of 3 to 30, a base of an aromatic ring having a carbon number of 6 to 30, a base of a heterocyclic structure having a carbon number of 3 to 30, or a carbon number of 2 to 20 - a group of NR ^B R ^C , when L is a single bond, R ¹ is a single bond or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms adjacent to a fluorine atom not bonded to a carbon atom of SO ₃ ^- , G is an alicyclic hydrocarbon group having a carbon number of 7 to 30 or a NR ^B R ^C group having a carbon number of 2 to 20, and R ^B and R ^{C are} each independently an alkyl group having 1 to 10 carbon atoms or carbon. a cycloalkyl group of 3 to 10, or a ring structure of 3 to 20 ring members which are bonded to the nitrogen atoms bonded to the groups, X is a halogen atom, and E ⁺ is an alkali metal ion. M ⁺ is 1 price The radioactive decomposed phosphonium cation, Y ^- is a monovalent anion.

In the above step (A), the organic halide represented by the above formula (ia) and the sulfite represented by E ₂ SO ₃ are reacted in, for example, a methanol/water mixed solvent to obtain the above formula (ib). Sulfonic acid salt.

Next, in the above step (B), the sulfonate is reacted with a sulfonium salt represented by MY using a solvent such as dichloromethane/water to obtain a compound represented by the above formula (1). After the reaction, the compound (I) can be obtained by an appropriate treatment such as liquid separation washing or column chromatography.

The content of the [B] acid generator is preferably from 0.1 part by mass to 30 parts by mass, more preferably from 0.2 part by mass to 20 parts by mass, even more preferably from 0.5 part by mass to 10 parts by mass per 100 parts by mass of the [A] polymer. The mass part is preferably from 1 part by mass to 5 parts by mass.

Further, when the radiation sensitive resin composition contains the other acid generator [D] described later, the content of the [B] acid generator is 100 mol%, preferably 5 mol, based on the other acid generator of [D]. %~100% by mole, more preferably 10% by mole to 60% by mole, and even more preferably 20% by mole to 50% by mole.

By setting the content of the [B] acid generator to the above range, the LWR performance and the like of the radiation sensitive resin composition can be further improved.

<[C] Solvent>

The solvent [C] is a component which dissolves or disperses the [A] polymer, the [B] acid generator, and optional components. The solvent of [C] is exemplified by an alcohol solvent, a ketone solvent, a guanamine solvent, an ether solvent, an ester solvent, and the like. The solvent may be used singly or in combination of two or more.

The alcohol solvent is exemplified by, for example, a monool solvent: methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, second butanol, third butanol, n-pentanol, isoamyl alcohol, 2-methylbutanol, second pentanol, third pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, second hexanol, 2-ethylbutanol, second g Alcohol, 3-heptanol, n-octanol, 2-ethylhexanol, second octanol, n-nonanol, 2,6-dimethyl-4-heptanol, n-nonanol, second-undecane Alcohol, trimethyl decyl alcohol, second-tetradecanol, second heptadecyl alcohol, decyl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol , benzyl alcohol, diacetone alcohol, etc.; polyol solvent is ethylene glycol, 1,2-propanediol, 1,3-butanediol, 2,4-pentanediol, 2-methyl-2,4- Pentandiol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, etc.; The polyol partial ether solvent is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol single Phenyl ether Ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, two Ethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl Ether, etc.

The ketone solvent is exemplified by, for example, a chain ketone solvent: acetone, methyl ethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, diethyl ketone, methyl isobutyl ketone, methyl N-pentyl Ketone, ethyl n-butyl ketone, methyl n-hexyl ketone, diisobutyl ketone, trimethyl fluorenone, 2,4-pentanedione, acetyl ketone, diacetone alcohol, acetophenone, etc.; The ketone solvent is cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone or the like.

The above amide-based solvent is exemplified by, for example, a chain amide-based solvent of N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropionamide, etc.; the cyclic guanamine solvent is N-methylpyrrolidone, N,N'-dimethylimidazole Ketones, etc.

The ether solvent is, for example, a chain ether solvent such as diethyl ether, dipropyl ether, dibutyl ether or diphenyl ether; and the cyclic ether solvent is tetrahydrofuran or tetrahydropyran.

The ester solvent is exemplified by, for example, an acetate solvent such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, second butyl acetate, or acetic acid. Amyl ester, second amyl acetate, 3-methoxybutyl acetate, methyl amyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, acetic acid Methylcyclohexyl ester, n-decyl acetate, glycol diacetate, methoxy triethylene glycol acetate, etc.; the acetate solvent of the partial ether of the polyol is ethylene glycol monomethyl ether, ethylene glycol Alcohol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether, acrylic acid Alcohol monomethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, etc.; carbonate solvent is carbonic acid Dimethyl ester, diethyl carbonate, etc.; other carboxylic acid ester solvents are methyl acetoxyacetate, ethyl acetoacetate, ethyl propionate, n-butyl propionate, isoamyl propionate, oxalic acid Diethyl ester, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate, and the like.

Among these, a ketone solvent and an ester solvent are preferred, and the ketone solvent is preferably a cyclic ketone solvent, more preferably cyclohexanone, and the ester solvent is an acetate partial solvent of a polyol partial ether. More preferably, it is preferably propylene glycol monomethyl ether.

<[D] Other acid generators>

[D] The other acid generator is a radioactive acid generator other than the above [B] acid generator, which is a sulfonate compound and a carbon atom adjacent to -SO ₃ ^- in the sulfonate compound. The upper bond has two or more fluorine atoms. According to [D] other acid generator, when the structural unit of the acid-dissociable group of the [A] polymer is, for example, the structural unit (I-1), the acid produced by the acid generator can be used as a catalyst to cause an acid. Dissociative group dissociation. As a result, the sensitivity of the radiation sensitive resin composition can be improved. [D] The other acid generators may be used alone or in combination of two or more.

[D] Other acid generators are exemplified by, for example, phosphonium salts, tetrahydrothiophenes. Anthracene salt compounds such as barium salts and barium salts.

The above onium salts are exemplified by, for example, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluorobutanesulfonate, triphenylsulfonium perfluorooctanesulfonate, cyclohexyl 2-oxocyclohexane. Hexylmethyl fluorene trifluoromethane sulfonate, dicyclohexyl 2-oxocyclohexyl fluorene trifluoromethane sulfonate, 2-oxocyclohexyl dimethyl fluorene trifluoromethane sulfonate, 4-hydroxy-1 -naphthyldimethylsulfonium trifluoromethanesulfonate, triphenylsulfonium 2-(adamantan-1-yl)-1,1-difluoroethane-1-sulfonate, triphenylsulfonium 4- (adamantan-1-ylcarbonyloxy)-1,1,2,2-tetrafluorobutane-1-sulfonate, and the like.

The above tetrahydrothiophene sulfonium salt is exemplified by, for example, 4-hydroxy-1-naphthyltetrahydrothiophene trifluoromethanesulfonate, 4-hydroxy-1-naphthyltetrahydrothiophene nonafluoro-n-butane sulfonate, 4 -hydroxy-1-naphthyltetrahydrothiophene perfluoro-n-octane sulfonate, 1-(1-naphthylethylidenemethyl)tetrahydrothiophene trifluoromethanesulfonate, 1-(1-naphthyl) Ethylmethyl)tetrahydrothiophene nonafluoro-n-butanesulfonate, 1-(1-naphthylethylidenemethyl)tetrahydrothiophene perfluorooctanesulfonate, 1-(3,5- Dimethyl-4-hydroxyphenyl)tetrahydrothiophene trifluoromethanesulfonate, 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophene nonafluoro-n-butane sulfonate And 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophene fluorinated perfluorooctane sulfonate.

The above onium salts are exemplified by, for example, diphenylsulfonium trifluoromethanesulfonate, diphenylsulfonium nonafluorobutanesulfonate, diphenylphosphonium perfluorooctanesulfonate, and bis (4-third) Phenyl) fluorinated trifluoromethanesulfonate, bis(4-t-butylphenyl)phosphonium nonafluorobutane sulfonate, bis(4-t-butylphenyl)phosphonium perfluoro-n-octane Sulfonate and the like.

Among these, a phosphonium salt compound is preferred, more preferably a phosphonium salt, and more preferably triphenylsulfonium 2-(adamantan-1-ylcarbonyloxy)-1,1,2,2-tetrafluorobutene. Alkane-1-sulfonate.

[D] The content of the other acid generator is preferably from 0.1 part by mass to 30 parts by mass based on 100 parts by mass of the [A] polymer, from the viewpoint of sensitivity and developability of the radiation-sensitive linear resin composition. It is preferably from 0.3 part by mass to 20 parts by mass, more preferably from 1 part by mass to 15 parts by mass. When the content of the other acid generator is less than the above lower limit, the sensitivity and developability of the radiation-sensitive resin composition tend to decrease. When the content of the other acid generator exceeds the above upper limit, the transparency of the radiation-sensitive resin composition is less likely to be transparent to the radiation, and it is difficult to obtain a rectangular resist pattern.

<[E] Compound containing a nitrogen atom>

[E] The compound containing a nitrogen atom is a compound containing a nitrogen atom. [E] The compound containing a nitrogen atom can inhibit the diffusion of an acid generated by the [B] acid generator or [D] other acid generator. In addition to the above-mentioned [B] acid generator, the radiation-sensitive resin composition can further improve LWR performance and the like by further containing the above-mentioned [E] nitrogen atom-containing compound. [E] The compound containing a nitrogen atom may be used alone or in combination of two or more.

[E] The compound containing a nitrogen atom is exemplified by, for example, an amine compound, a guanamine group-containing compound, a urea compound, a nitrogen-containing heterocyclic compound, and the like.

The above amine compounds are exemplified by, for example, mono(cyclo)alkylamines; di(cyclo)alkylamines; tri(cyclo)alkylamines; substituted alkylanilines or derivatives thereof; ethylenediamine, N, N,N',N'-tetramethylethylenediamine, Tetramethyldiamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl Methyl ketone, 4,4'-diaminodiphenylamine, 2,2-bis(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminobenzene Propane, 2-(4-aminophenyl)-2-(3-hydroxyphenyl)propane, 2-(4-aminophenyl)-2-(4-hydroxyphenyl)propane, 1, 4-bis(1-(4-aminophenyl)-1-methylethyl)benzene, 1,3-bis(1-(4-aminophenyl)-1-methylethyl)benzene, Bis(2-dimethylaminoethyl)ether, bis(2-diethylaminoethyl)ether, 1-(2-hydroxyethyl)-2-imidazolidinone, 2-quinoxalinol, N , N, N', N'-肆 (2-hydroxypropyl) ethylenediamine, N, N, N', N", N"-pentamethyldiethylenetriamine and the like.

The above-mentioned amide group-containing compound is exemplified by an N-tert-butoxycarbonyl group-containing amine compound such as N-tert-butoxycarbonyl-4-hydroxypiperidine; N-third pentyloxycarbonyl-4- N-tert-methoxycarbonyl-containing amine compound such as hydroxypiperidine; formamide, N-methylformamide, N,N-dimethylformamide, acetamide, N-methyl Indoleamine, N,N-dimethylacetamide, acetamide, benzamide, pyrrolidone, N-methylpyrrolidone, N-ethinyl-1-adamantanamine, guanidinium isocyanurate (2- Hydroxyethyl) ester and the like.

The above urea compounds are exemplified by, for example, urea, methyl urea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenyl. Urea, tri-n-butyl thiourea, and the like.

The nitrogen-containing heterocyclic compound is exemplified by, for example, an imidazole such as 2-phenylimidazole; a pyridine; a piperazine; a pyrazine, a pyrazole, a pyridazine, a quinoxaline, an anthracene, a pyrrolidine, a piperidine, or a piperidine. 3-piperidinyl-1,2-propanediol, morpholine, 4-methylmorpholine, 1-(4-morpholinyl)ethanol, 4-ethylidene Morpholine, 3-(N-morpholinyl)-1,2-propanediol, 1,4-dimethylpiperazine, 1,4-diazabicyclo[2.2.2]octane, and the like.

Among these, a compound containing a guanamine group is preferred, more preferably an N-tert-butoxycarbonyl-containing amine compound, more preferably N-tert-butoxycarbonyl-4-m-piperidine. .

The content of the [E] nitrogen atom-containing compound is preferably 30 parts by mass or less, more preferably 0.1 part by mass to 20 parts by mass, even more preferably 0.5 part by mass to 10 parts by mass per 100 parts by mass of the [A] polymer. Share. By setting the content of the [E] nitrogen atom-containing compound to the above range, the LWR performance and the like of the radiation sensitive resin composition can be further improved.

<[F] Polymer of fluorine atom>

[F] The polymer of a fluorine atom is a fluorine atom-containing polymer. According to the radiation sensitive resin composition, the polymer of the [F] fluorine atom is biased to the formed resist film by a polymer further containing [F] fluorine atom in addition to the [A] polymer. The surface layer can improve the hydrophobicity of the surface of the resist film. Thereby, when the liquid immersion exposure is performed, etc., the substance elution suppressing property from the resist film is excellent, and the retreat contact angle of the resist film and the liquid immersion liquid can be sufficiently increased, and higher-speed scanning can be performed.

[F] The polymer of the fluorine atom is not particularly limited, and is exemplified by (1) itself which is insoluble in the developing solution, which becomes an alkali-soluble polymer by the action of an acid, and (2) which is soluble in the image itself. In the liquid, the alkali-soluble polymer is increased by the action of an acid, (3) it is insoluble in the developing solution itself, becomes an alkali-soluble polymer by the action of the alkali, and (4) itself It is soluble in a developing solution, and an alkali-soluble polymer or the like is increased by the action of a base.

[F] A form of a fluorine atom-containing polymer is exemplified by a structure in which a fluorinated alkyl group is bonded to a main chain, a structure in which a fluorinated alkyl group is bonded to a side chain, and a main chain and a side chain. The structure of the fluorinated alkyl group is bonded to the bond.

The monomer obtained by the structure in which a fluorinated alkyl group is bonded to the main chain is exemplified by, for example, an α-trifluoromethacrylate compound, a β-trifluoromethacrylate compound, and α,β-trifluoromethacrylate. A compound or a compound in which one or more hydrogen atoms of a vinyl moiety are substituted by a fluorinated alkyl group such as a trifluoromethyl group.

The monomer having a structure in which a fluorinated alkyl group is bonded to a side chain is exemplified by a fluorinated alkyl group or a derivative thereof, such as norbornene or the like, a fluorinated alkyl group or a derivative thereof, acrylic acid or methacrylic acid. The side chain is an ester compound of a fluorinated alkyl group or a derivative thereof, and a side chain (a site containing no double bond) of one or more kinds of olefins is a fluorinated alkyl group or a derivative thereof.

The monomer having a structure in which a fluorinated alkyl group is bonded to the main chain and the side chain is exemplified by, for example, α-trifluoromethacrylic acid, β-trifluoromethylacrylic acid, α,β-trifluoromethacrylic acid, or the like. The side chain is an ester compound of a fluorinated alkyl group or a derivative thereof, and a side chain of a compound in which one or more hydrogen atoms of a vinyl moiety are substituted with a fluorinated alkyl group such as a trifluoromethyl group is subjected to a fluorinated alkyl group or a derivative thereof. The substituent, one or more hydrogen atoms bonded to the double bond of the alicyclic olefin compound are substituted by a fluorinated alkyl group such as a trifluoromethyl group, and the side chain is a fluorinated alkyl group or a derivative thereof. . Further, the alicyclic olefin compound is one of the rings Part of the compound is a double bond.

The polymer of the fluorine atom-containing atom preferably has a structural unit (f1) represented by the following formula (6) and/or a structural unit (f2) represented by the following formula (7). Further, the [F] fluorine atom-containing polymer may have "other structural units" other than the structural unit (f1) and the structural unit (f2). Further, the polymer of the [F] fluorine-containing atom may contain one or two or more structural units. The following is a detailed description of each structural unit.

[structural unit (f1)]

The structural unit (f1) is a structural unit represented by the following formula (6).

In the above formula (6), R ^f1 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R ^f2 is a linear or branched alkyl group having 1 to 6 carbon atoms of a fluorine atom or a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms and having a fluorine atom. However, some or all of the hydrogen atoms of the above alkyl group and the alicyclic hydrocarbon group may be substituted.

The linear or branched alkyl group having 1 to 6 carbon atoms is exemplified by a methyl group, an ethyl group, a propyl group, a butyl group or the like.

The above-mentioned monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms is exemplified by, for example, a cyclopentyl group, a cyclopentylpropyl group, a cyclohexyl group, a cyclohexylmethyl group, a cycloheptyl group, and a ring. Octyl, cyclooctylmethyl and the like.

The monomer which obtains the structural unit (f1) is exemplified by, for example, trifluoromethyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, perfluoroethyl (meth)acrylate, (a) Perfluoropropyl n-propyl acrylate, perfluoroisopropyl (meth) acrylate, perfluoro-n-butyl (meth) acrylate, perfluoroisobutyl (meth) acrylate, perfluoro(meth) acrylate Tributyl ester, perfluorocyclohexyl (meth)acrylate, 2-(1,1,1,3,3,3-hexafluoro)propyl (meth)acrylate, 1-(2) (meth)acrylate , 2,3,3,4,4,5,5-octafluoro)pentyl ester, 1-(2,2,3,3,4,4,5,5-octafluoro)hexyl (meth)acrylate , (Perfluorocyclohexyl methyl (meth) acrylate, 1-(2, 2, 3, 3, 3-pentafluoro) propyl (meth) acrylate, 1-(2, 2, 3) (meth) acrylate ,3,4,4,4-heptafluoro)pentyl ester, (meth)acrylic acid 1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9 ,10,10,10-heptadecafluoro)decyl ester, 1-(5-trifluoromethyl-3,3,4,4,5,6,6,6-octafluoro)hexyl (meth)acrylate Wait.

The structural unit (f1) is preferably a structural unit represented by the following formulas (6-1) and (6-2).

In the above formulae (6-1) and (6-2), R ^f1 is synonymous with the above formula (6).

Among these, it is more preferably a structural unit represented by the formula (6-1).

The content ratio of the structural unit (f1) is preferably from 10 mol% to 70 mol%, more preferably from 20 mol% to 50 mol%, based on the entire structural unit of the polymer constituting the [F] fluorine atom. .

[structural unit (f2)]

The structural unit (f2) is a structural unit represented by the following formula (7).

In the above formula (7), R ^f3 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R ^f4 is a linking group of (k+1) valence. X ¹ is a divalent linking group having a fluorine atom. R ^f5 is a hydrogen atom or a monovalent organic group. K is an integer from 1 to 3. However, when k is 2 or 3, the plurality of X ¹ and R ^f5 may be the same or different.

In the above formula (7), the (k+1)-valent linking group represented by R ^f4 is, for example, a linear or branched hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, or carbon. a number of 6 to 30 aromatic hydrocarbon groups, or a combination of one or more groups selected from the group consisting of an oxygen atom, a sulfur atom, an ether group, an ester group, a carbonyl group, an imine group, and a guanamine group. The foundation of the foundation. Further, the above (k+1)-valent linking group may have a substituent.

The above-mentioned linear or branched hydrocarbon group having 1 to 30 carbon atoms is exemplified by a hydrocarbon group such as methane, ethane, propane, butane, pentane, hexane, heptane, decane, eicosane or triacontan. The basis of (k+1) hydrogen atoms is removed.

The above-mentioned alicyclic hydrocarbon group having 3 to 30 carbon atoms is exemplified by, for example, a group in which (k+1) hydrogen atoms are removed from the following: cyclopropane, cyclobutane, cyclopentane, cyclohexane of a monocyclic saturated hydrocarbon Alkane, cycloheptane, cyclooctane, cyclodecane, methylcyclohexane, ethylcyclohexane, etc.; cyclobutene, cyclopentene, cyclohexene, cycloheptene, monocyclic unsaturated hydrocarbons, Cyclooctene, cyclodecene, cyclopentadiene, cyclohexadiene, cyclooctadiene, cyclodecadiene, etc.; polycyclic saturated hydrocarbon bicyclo [2.2.1] heptane, bicyclo [2.2.2] Octane, tricyclo[5.2.1.0 ^2,6 ]decane, tricyclo[3.3.1.1 ^3,7 ]decane, tetracyclo[6.2.1.1 ^3,6 .0 ^2,7 ]dodecane, adamantane Etc; polycyclic unsaturated hydrocarbon bicyclo [2.2.1] heptene, bicyclo [2.2.2] octene, tricyclo [5.2.1.0 ^2,6 ] decene, tricyclo[3.3.1.1 ^3,7 ] Terpene, tetracyclo[6.2.1.1 ^3,6 .0 ^2,7 ] dodecene and the like.

The above aromatic hydrocarbon group having 6 to 30 carbon atoms is exemplified by, for example, benzene, naphthalene, phenanthrene, anthracene, tetracene, pentacene, fluorene, picene, toluene, xylene, ethylbenzene, mesitylene, An aromatic hydrocarbon such as cumene removes a base of (k+1) hydrogen atoms.

In the above formula (7), the divalent linking group having a fluorine atom represented by X ¹ is, for example, a divalent linear hydrocarbon group having 1 to 20 carbon atoms and having a fluorine atom. X ¹ is, for example, a group represented by the following formulas (X1-1) to (X1-6).

X ^{1 is} preferably a group represented by the above formulas (X1-1) and (X1-2), more preferably a group represented by the formula (X1-2).

In the above formula (7), the monovalent organic group represented by R ^f5 is, for example, a linear or branched hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, and a carbon number of 6 to 30. The aromatic hydrocarbon group or a group in which the group is combined with one or more groups selected from the group consisting of an oxygen atom, a sulfur atom, an ether group, an ester group, a carbonyl group, an imine group, and a guanamine group.

The structural unit (f2) is exemplified by a structural unit represented by the following formula (7-1) and formula (7-2).

In the above formula (7-1), R ^f4 is a saturated or unsaturated hydrocarbon group having a chain-like, branched or cyclic chain of 1 to 20 carbon atoms. R ^f3 , X ¹ and R ^{f5 are} synonymous with the above formula (7).

In the above formula (7-2), R ^f3 , X ¹ , R ^f5 and k have the same meanings as in the above formula (7). However, when k is 2 or 3, the plurality of X ¹ and R ^f5 may be the same or different.

The structural unit represented by the above formula (7-1) and formula (7-2) is, for example, represented by the following formulas (7-1-1) to (7-1-3) and formula (7-2-1). Construction unit, etc.

In the above formulae (7-1-1) to (7-1-3) and (7-2-1), R ^f3 is synonymous with the above formula (7).

The structural unit (f2) is preferably a structural unit represented by the above formula (7-1), and more preferably a structural unit represented by the above formula (7-1-3).

The monomer which obtains the structural unit (f2) is exemplified by, for example, [2-(1-ethyloxycarbonyl-1,1-difluoro-n-butyl)](meth)acrylate, (meth)acrylic acid (1, 1,1-trifluoro-2-trifluoromethyl-2-hydroxy-3-propyl)ester, (meth)acrylic acid (1,1,1-trifluoro-2-trifluoromethyl-2-hydroxyl) -4-butyl)ester, (1,1,1-trifluoro-2-trifluoromethyl-2-hydroxy-5-pentyl) (meth)acrylate, 2-{[()(meth)acrylate 5-(1',1',1'-trifluoro-2'-trifluoromethyl-2'-hydroxy)propyl]bicyclo[2.2.1]heptyl}ester. Among these, [2-(1-ethyloxycarbonyl-1,1-difluoro-n-butyl)] (meth)acrylate is preferred.

The content ratio of the structural unit (f2) is relative to the composition [F] The total structural unit of the polymer of the fluorine atom is preferably from 30 mol% to 90 mol%, more preferably from 50 mol% to 80 mol%.

[Other construction units]

[F] The fluorine atom-containing polymer may also contain "other structural units" other than the structural unit (f1) and the structural unit (f2). Other structural units are listed, for example, as structural units (I) of [A] polymer and the like.

The content ratio of the other structural unit is preferably from 5 mol% to 90 mol%, more preferably from 10 mol% to 80 mol%, and more preferably from 10 mol% to 80 mol%, and more preferably the total structural unit of the polymer constituting the [F] fluorine atom. Good for 20% to 70%.

The content of the polymer of the fluorine atom-containing atom is preferably 20 parts by mass or less, more preferably 0.1 part by mass to 15 parts by mass, even more preferably 1 part by mass to 10 parts by mass per 100 parts by mass of the [A] polymer. The portion is preferably from 1 part by mass to 6 parts by mass. When the content of the polymer of the fluorine-containing atom exceeds the above upper limit, the water repellency of the surface of the resist film may be too high to cause development failure.

The fluorine atom content of the [F] fluorine atom-containing polymer is preferably larger than the fluorine atom content of the [A] polymer. When the fluorine atom content in the polymer of the fluorine atom-containing polymer is larger than that of the [A] polymer, the composition of the radiation-sensitive resin containing the polymer containing the [A] polymer and the [F] fluorine atom can be further improved. The water repellency of the surface of the resist film formed by the object. The difference between the fluorine atom content of the [F] fluorine-containing polymer and the fluorine atom content of the [A] polymer is preferably 1% by mass or more, more preferably 3% by mass or more.

Further, the fluorine atom content of the [F] fluorine atom-containing polymer is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and most preferably 10% by mass or more.

In addition, the fluorine atom content (% by mass) was determined by ¹³ C-NMR to determine the structure of the polymer, and its structure was calculated.

<[F] Synthesis method of polymer containing fluorine atom>

The [F] fluorine atom-containing polymer can be produced, for example, by polymerizing a monomer corresponding to each specific structural unit in a suitable solvent using a radical polymerization initiator.

The radical polymerization initiator is exemplified by, for example, the same as the radical polymerization initiator used in the synthesis method of the [A] polymer. The above-mentioned polymerization solvent is exemplified by, for example, the same as the polymerization solvent used in the synthesis method of the [A] polymer.

The reaction temperature in the above polymerization is usually from 40 ° C to 150 ° C, preferably from 50 ° C to 120 ° C. The reaction time is usually from 1 hour to 48 hours, preferably from 1 hour to 24 hours.

The Mw of the [F] fluorine atom-containing polymer is preferably from 1,000 to 50,000, more preferably from 2,000 to 30,000, still more preferably from 3,000 to 10,000. When the Mw of the [F] fluorine-containing polymer is less than 1,000, a sufficient receding contact angle cannot be obtained. On the other hand, when Mw exceeds 50,000, the development property as a resist tends to decrease.

The ratio of Mw to Mn (Mw/Mn) of the [F] fluorine atom-containing polymer is preferably from 1 to 5, more preferably from 1 to 3.

<[G] partialization accelerator>

The [G] biasing accelerator is a component which causes the [F] fluorine atom-containing polymer to more effectively segregate on the surface of the resist film. By including the [G] biasing accelerator in the radiation sensitive resin composition, the polymer of the [F] fluorine atom can be more effectively segregated on the surface of the resist film, and as a result, [F] fluorine atom polymerization can be reduced. The amount of use of the object. The [G] partialization accelerator is exemplified by a lactone compound, a carbonate compound, a nitrile compound, a polyhydric alcohol, and the like. The [G] partialization accelerator may be used singly or in combination of two or more.

The above lactone compound is exemplified by, for example, γ-butyrolactone, valerolactone, mevalononitrile, norbornane lactone and the like.

The above carbonate compound is exemplified by, for example, propyl carbonate, ethyl carbonate, butyl carbonate, and vinyl carbonate.

The above nitrile compound is exemplified by, for example, succinonitrile.

The above polyol is exemplified by glycerin or the like.

Among these, a lactone compound is preferred, and more preferably γ-butyrolactone.

The content of the [G] partialization accelerator is preferably from 5 parts by mass to 300 parts by mass, more preferably from 10 parts by mass to 100 parts by mass, even more preferably from 20 parts by mass to 100 parts by mass per 100 parts by mass of the [A] polymer. Parts by mass.

<Other optional ingredients>

The radiation sensitive resin composition may contain, in addition to the above components [A] to [G], a compound which forms a carboxylic acid by irradiation of radiation, and an interface. Other optional components such as an active agent, a compound containing an alicyclic skeleton, and a sensitizer. Each of the components of the other optional components may be used alone or in combination of two or more. In addition, the content of other optional components may be appropriately determined depending on the purpose thereof.

The compound which generates a carboxylic acid by irradiation with the above-mentioned radiation is usually a carboxylate compound composed of a radiation-decomposable phosphonium cation and a carboxylate anion. The carboxylate anion can capture an acid produced by the [D] other acid generator, but the radiation-decomposable cation is decomposed by radiation irradiation in the exposed portion to form a proton, and the carboxylic acid is generated from the proton and the carboxylate anion. Therefore, the above-mentioned acid capture function is degraded. According to this, since the compound which generates a carboxylic acid by irradiation of radiation has a function of suppressing acid diffusion in the unexposed portion, the contrast between the exposed portion and the unexposed portion is further improved, and as a result, the lithography of the radiation-sensitive resin composition is improved. performance.

The above carboxylate compounds are exemplified by, for example, triphenylsulfonium salicylate, tert-butylphenyldiphenylsulfonium salicylate, triphenylsulfonium acetate, naphthyldiphenylphosphonium acetate, triphenylbenzene. Base butyrate, triphenylsulfonium 2,2-dimethylpropionate, triphenylsulfonium pentafluorobenzoate, diphenylsulfonium benzoate and the like.

The content of the compound which generates a carboxylic acid by irradiation with radiation is preferably from 0 part by mass to 20 parts by mass, more preferably from 0.1 part by mass to 15 parts by mass, per 100 parts by mass of the [A] polymer. The lithographic performance of the radiation sensitive resin composition is further improved by setting the content to the above range.

<Modulation method of radiation sensitive resin composition>

The radiation sensitive resin composition can be prepared by mixing each component such as [A] polymer, [B] acid generator, [C] solvent, and optionally [D] other acid generator in a specific ratio.

The solid content concentration of the radiation sensitive resin composition is preferably from 0.1% by mass to 50% by mass, more preferably from 0.5% by mass to 30% by mass, even more preferably from 1% by mass to 10% by mass.

<Formation method of resist pattern>

The method for forming a resist pattern has the steps of: forming a resist film using the radiation-sensitive resin composition (hereinafter also referred to as "resist film forming step"), and exposing the resist film ( Hereinafter, it is also referred to as "exposure step"), and a step of developing the exposed resist film (hereinafter also referred to as "development step").

Hereinafter, each step will be described.

[Resist film forming step]

In this step, a resist film is formed using the above-described radiation sensitive resin composition of the present invention. The coating method is not particularly limited, and suitable coating means such as spin coating, casting coating, roll coating, or the like can be employed. The substrate is exemplified by, for example, a germanium wafer, a wafer coated with aluminum, or the like. Specifically, after the composition is applied such that the obtained resist film has a predetermined thickness, it is pre-baked (PB) as needed to volatilize the solvent in the coating film. The film thickness of the coating film is preferably 10nm~500nm. The temperature of PB is usually from 60 ° C to 140 ° C, preferably from 80 ° C to 120 ° C. The time of PB is usually 5 seconds to 600 seconds, preferably 10 seconds to 300 seconds.

[Exposure step]

This step exposes the resist film formed in the above-described resist film forming step. This exposure is performed by interposing radiation through a mask having a specific pattern depending on the liquid immersion medium such as water. The radiation is based on the line width of the target pattern, and is appropriately selected from, for example, visible light, ultraviolet light, far ultraviolet light, EUV (wavelength 13.5 nm), electromagnetic waves such as X-rays and gamma rays, and charged particle beams such as electron beams and alpha rays. . In the above, the [A] polymer of the radiation-sensitive resin composition has a structural unit (I-1), etc., and is preferably far ultraviolet rays, more preferably ArF excimer laser light (wavelength 193 nm), KrF excimer. Laser light (wavelength 248 nm), and better ArF excimer laser light. Further, the [A] polymer of the radiation sensitive resin composition has a structural unit (I-2), and the like, and is preferably an electron beam or EUV.

Further, after exposure, post-exposure baking (PEB) is preferably performed. By performing PEB, the dissociation reaction of the acid dissociable group in the exposed portion of the resist film can be smoothly performed. The temperature of the PEB is usually from 50 ° C to 180 ° C, preferably from 80 ° C to 130 ° C. The PEB time is usually 5 seconds to 600 seconds, preferably 10 seconds to 300 seconds.

In the present invention, in order to maximize the potential of the radiation-sensitive resin composition, it is also possible to pre-form, for example, on a substrate to be used. An organic or inorganic antireflective film. Further, in order to prevent the influence of alkaline impurities and the like contained in the environment, for example, a protective film may be provided on the coating film. Further, in the case of performing immersion exposure, in order to prevent the liquid immersion medium from coming into direct contact with the resist film, for example, a protective film for liquid immersion may be provided on the resist film.

[development step]

This step develops the resist film exposed in the above exposure step. The developing solution used for the development is exemplified by an alkali developing solution, an organic solvent developing solution, and the like. Thereby, a specific resist pattern is formed.

The above alkali developing solution is exemplified by, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium citrate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine. , triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide (TMAH), pyrrole, piperidine, choline, 1,8-diazabicyclo-[ 5.4.0] An alkaline aqueous solution obtained by dissolving at least one of a basic compound such as 7-undecene or 1,5-diazabicyclo-[4.3.0]-5-decene.

The organic solvent developing solution is exemplified by, for example, an alcohol solvent such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol or second butanol; and the ether solvent is diethyl ether and Propyl ether, dibutyl ether, tetrahydrofuran, dioxane, diphenyl ether, anisole, etc.; the ketone oxime solvent is acetone, methyl ethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone Ethamamine solvent N, N'-dimethylimidazolidinone, N-methylformamidine An amine, N,N-dimethylformamide or the like; the ester solvent is diethyl carbonate, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate or n-butyl acetate.

These developing solutions may be used singly or in combination of two or more. Further, after development, it is generally washed with water or the like and dried.

<Sense Radiation Acid Generator>

The radiation-sensitive acid generator of the present invention is a compound represented by the above formula (1). Since the radiation sensitive resin composition has the above characteristics, the LWR performance and the like of the radiation sensitive resin composition can be improved.

Compound

The compound of the present invention is a compound represented by the above formula (1). Since the compound has the above structure, it can be preferably used as a compound constituting the radiation-sensitive acid generator.

<Method of Manufacturing Compounds>

The method for producing the compound of the present invention is a method for producing a compound represented by the following formula (1): (A) an organic halide represented by the following formula (ia) and a sulfurous acid represented by E ₂ SO ₃ The salt is reacted to obtain a sulfonate represented by the following formula (ib), and (B) a step of reacting the above sulfonate with an onium salt represented by MY.

According to the method for producing the compound, the compound can be produced easily and in good yield.

The radiation-sensitive acid generator, the compound, and the method for producing the compound are described in the [B] acid generator of the above-described radiation-sensitive resin composition.

[Examples]

The present invention is specifically described below based on examples, but the present invention is not limited by the examples. The measurement methods of various physical property values are shown below.

[Weight average molecular weight (Mw), number average molecular weight (Mn), and degree of dispersion (Mw/Mn)]

The Mw and Mn of the polymer were measured by a gel permeation chromatography (GPC) using a GPC column (two G2000HXL, one G3000HXL, and one G4000HXL) manufactured by TOSOH under the following conditions. Further, the degree of dispersion (Mw/Mn) was calculated from the measurement results of Mw and Mn.

Dissolution solvent: tetrahydrofuran

Flow rate: 1.0mL/min

Sample concentration: 1.0% by mass

Sample injection amount: 100 μL

Column temperature: 40 ° C

Detector: differential refractometer

Reference material: monodisperse polystyrene

[Content of low molecular weight fraction]

[A] The content (% by mass) of the low molecular weight component (component having a molecular weight of less than 1,000) in the polymer is a high-speed liquid chromatograph (HPLC) using an HPLC column (Intersil ODS-25 μm, 4.6) manufactured by JL Science. Mm ×250 mm), measured under the following conditions.

Dissolution solvent: acrylonitrile / 0.1% by mass phosphoric acid aqueous solution

Flow rate: 1.0mL/min

Sample concentration: 1.0% by mass

Sample injection amount: 100 μL

Detector: differential refractometer

[ ¹³ C-NMR analysis]

The ¹³ C-NMR analysis for determining the ratio of each constituent unit of the polymer was measured using a nuclear magnetic resonance apparatus (JNM-ECX400, manufactured by JEOL Ltd.).

<Synthesis of Compound (I)>

The compound (I) was synthesized by the method shown in the following reaction scheme.

In the above reaction scheme, G is adamantane-1-yl, adamantyl-1-ylmethyl, adamantane-2-yl, N-azetidinyl, 3,5-dimethyladamantane-1- , 5-oxo-4-oxatricyclo[4.3.1.1 ^3,8 ]undecyl, 4-oxoadamantan-1-yl, 3-hydroxyadamantan-1-yl or 3-( 2,2-Dimethyl-1,3-dioxycyclopentane-5-yl)-7,7-dimethyl-4,6,8-trioxybicyclo[3.3.0]octane- 2-based. L is a single bond, -COO-*, -O-, -S-, -CONH- or -SO ₂ O-. * indicates the bonding site with G. R ¹ is a single bond, a 1,4-butanediyl group, a 1,3-propanediyl group or a 1,2-ethanediyl group.

[Example 1]

After feeding 2.0 g (6.3 mmol) of adamantyl 5-bromopentanoate, 50 mL of methanol and 30 mL of water in a 100 mL pear-shaped flask, 2.0 g (15.9 mmol) of sodium sulfite was added as a solid, and it was dispersed into a white turbidity. . After heating and stirring at 85 ° C for 10 hours, 100 mL of ethanol was added, and then the insoluble matter was removed by filtration. After distilling off the solvent, 1.52 g (5.1 mmol) of triphenylphosphonium chloride, 40 mL of dichloromethane and 30 mL of water were added, and the mixture was stirred at room temperature for 6 hours. The organic matter was extracted with dichloromethane and washed with water 5 times. Dry with anhydrous sodium sulfate Then, the solvent was distilled off and purified by column chromatography to obtain 2.30 g (yield: 78%) of the compound of the formula (S-1).

[Examples 2 to 17]

In the same manner as in Example 1, except that other derivatives were used instead of adamantyl-1-bromopentanoate as a starting material, the following formulas (S-2) to (S-17) were synthesized. Expressed as a compound.

<Synthesis of Polymers>

Each monomer used in the synthesis of the polymer of [A] polymer and [F] fluorine atom (hereinafter also referred to as "compound (M1-) to (M-6)") is shown below.

[[A] Synthesis of Polymers] [Synthesis Example 1]

9.01 g (50 mol%) of the above compound (M-1) and 10.99 g (50 mol%) of the compound (M-2) were dissolved in 40 g of 2-butanone, followed by use as a radical polymerization initiator The AIBN 0.81 g (5 mol% based on the total number of the above compounds) was dissolved to prepare a monomer solution. After injecting 20 g of 2-butanone into a 100 mL three-necked flask under nitrogen for 30 minutes, the mixture was heated to 80 ° C with stirring, and the above-prepared monomer solution was added dropwise over 3 hours with a dropping funnel. The polymerization reaction was carried out for 6 hours starting from the start of the dropwise addition as the start time of the polymerization reaction. After completion of the polymerization reaction, the polymerization reaction liquid was cooled to 30 ° C or lower by water cooling. The cooled polymerization reaction liquid was poured into 400 g of methanol, and the precipitated white powder was filtered. The filtered white powder was washed twice with 80 g of methanol, and then filtered and dried at 50 ° C for 17 hours to obtain a white powdery polymer (A-1) (15.6 g, yield 78%). The polymer (A-1) had a Mw of 7,200 and an Mw/Mn of 1.52. As a result of ¹³ C-NMR analysis, the content ratios of the structural units derived from the compound (M-1) and the compound (M-2) were 50.2 mol% and 49.8 mol%, respectively. The content of the low molecular weight portion in the polymer (A-1) was 0.04% by mass.

[Synthesis Example 2]

Compound (M-1) 9.53 g (50 mol%), compound (M-2) 9.29 g (40 mol%) and compound (M-3) 1.18 g (10 mol%) were dissolved in 2-butyl In 40 g of the ketone, 0.86 g (5 mol%) of AIBN as a radical polymerization initiator was dissolved to prepare a monomer solution. After injecting 20 g of 2-butanone into a 100 mL three-necked flask under nitrogen for 30 minutes, the mixture was heated to 80 ° C with stirring, and the above-prepared monomer solution was added dropwise over 3 hours with a dropping funnel. The polymerization reaction was carried out for 6 hours starting from the start of the dropwise addition as the start time of the polymerization reaction. After completion of the polymerization reaction, the polymerization reaction liquid was cooled to 30 ° C or lower by water cooling. The cooled polymerization reaction liquid was poured into 400 g of methanol, and the precipitated white powder was filtered. After the filtered white powder was washed twice with 80 g of methanol, it was filtered and dried at 50 ° C for 17 hours to synthesize a white powdery polymer (A-2) (14.1 g, yield 71%). The polymer (A-2) had a Mw of 7,100 and an Mw/Mn of 1.53. Further, as a result of ¹³ C-NMR analysis, the content ratios of the structural units derived from the compounds (M-1), (M-2), and (M-3) were 50.1 mol%, 40.6 mol%, and 9.3 mol, respectively. ear%. The content of the low molecular weight portion in the polymer (A-2) was 0.06% by mass.

[Synthesis Example 3]

55.0 g of the compound (M-4) and 45.0 g of the compound (M-5), 4 g of AIBN as a radical polymerization initiator, and 1 g of a third-dodecylmercaptan as a chain transfer agent were dissolved in propylene glycol monomethyl After 100 g of the ether, the reaction temperature was maintained at 70 ° C under a nitrogen atmosphere, and polymerization was carried out for 16 hours. After the polymerization, the polymerization reaction liquid was added to 1,000 g of n-hexane to solidify and purify the polymer. Then, 150 g of propylene glycol monomethyl ether was further added to the obtained polymer, and then 150 g of methanol, 34 g of triethylamine, and 6 g of water were further added, and hydrolysis reaction was carried out for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained polymer was dissolved in 150 g of acetone, and then added dropwise to 2,000 g of water to be solidified, and the resulting white powder was filtered and dried at 50 ° C for 17 hours to obtain a white powder. Polymer (A-3) (65.7 g, yield 76.6%). The polymer (A-3) had Mw of 10,000 and Mw/Mn of 2.1. Further, as a result of ¹³ C-NMR analysis, the content ratios of the structural unit derived from p-hydroxystyrene and the structural unit derived from the compound (M-5) were 65.4 mol% and 34.6 mol%, respectively. The content of the low molecular weight portion of the polymer (A-3) was 0.05% by mass.

[F] Synthesis of a fluorine atom-containing polymer] [Synthesis Example 4]

79.9 g (70 mol%) of the compound (M-1) and 20.91 g (30 mol%) of the compound (M-6) were dissolved in 100 g of 2-butanone, followed by use as a radical polymerization initiator. 2.77 g of 2,2'-azobisisobutyric acid dimethyl ester was dissolved to prepare a monomer solution. The 1,000-mL three-necked flask in which 100 g of 2-butanone was injected was blown with nitrogen for 30 minutes, and then heated to 80 ° C with stirring, and the above-prepared monomer solution was added dropwise over 3 hours with a dropping funnel. The polymerization reaction was carried out for 6 hours starting from the start of the dropwise addition as the start time of the polymerization reaction. After completion of the polymerization reaction, the polymerization reaction liquid was cooled to 30 ° C or lower by water cooling. After the reaction solution was pipetted into a 2 L separatory funnel, the polymerization reaction solution was uniformly diluted with 150 g of n-hexane, and 600 g of methanol was added thereto and mixed. Next, 30 g of distilled water was charged, and the mixture was further stirred and allowed to stand for 30 minutes. Subsequently, the lower layer was recovered, and by solvent displacement, a propylene glycol monomethyl ether acetate solution of the polymer (F-1) was obtained (yield 60%). The obtained polymer (F-1) had Mw of 7,200 and Mw/Mn of 2.00. Further, as a result of ¹³ C-NMR analysis, the content ratios of the structural units derived from the compounds (M-1) and (M-6) in the polymer (F-1) were 71.1 mol% and 28.9 mol%, respectively. . The content of the low molecular weight portion of the polymer (F-1) was 0.07% by mass.

<Modulation of Radiation-Linear Resin Composition>

The components used for the preparation of the radiation sensitive resin composition are shown below.

[[B] ingredients]

The compounds (S-1) to (S-17) synthesized above were used in the examples.

The following compounds (CS-1) to (CS-4) were used in the comparative examples.

CS-1: triphenylsulfonium 10-camphorsulfonate (compound represented by the following formula (CS-1))

CS-2: triphenylsulfonium cyclohexanesulfonate (compound represented by the following formula (CS-2))

CS-3: triphenylbutane-1-sulfonate (compound represented by the following formula (CS-3))

CS-4: triphenylsulfonium 4-(n-propylcarbonyloxy)-1-fluorobutane-1-sulfonate (compound represented by the following formula (CS-4)).

[[C]solvent]

C-1: propylene glycol monomethyl ether acetate

C-2: cyclohexanone

[[D]Other acid generators]

D-1: triphenylsulfonium 2-(adamantan-1-ylcarbonyloxy)-1,1,2,2-tetrafluorobutane-1-sulfonate (represented by the following formula (D-1)) Compound)

[[E] compounds containing nitrogen atoms]

E-1: N-t-butoxycarbonyl-4-hydroxypiperidine (compound represented by the following formula (E-1))

[[G] partialization accelerator]

G-1: γ-butyrolactone

[Modulation of Radiation-Resistant Resin Composition for ArF Exposure] [Embodiment 18]

100 parts by mass of (A-1) as the [A] polymer and (S-1) 30 mol% as the [B] acid generator (100 mol% relative to [D] other acid generators Ear ratio), (C-1) 2, 240 parts by mass of [C] solvent and (C-2) 960 parts by mass, (D-1) 8.5 parts by mass of [D] other acid generator, (F-1) 3 parts by mass of [F] fluorine atom-containing polymer, and as [G] 30 parts by mass of (G-1) of the partialization accelerator, and the radiation sensitive resin composition (J-1) was prepared.

[Examples 19 to 34 and Comparative Examples 1 to 5]

The radiation sensitive linear resin compositions (J-2) to (J-17) were prepared in the same manner as in Example 18 except that the components of the types and contents shown in the following Table 1 were used.

<Formation of resist pattern> (in the case of alkali imaging)

The composition for forming an underlying antireflective film (ARC66, manufactured by Brewer Science) was applied onto the surface of a 12-inch wafer using a spin coater (CLEAN TRACK ACT12, manufactured by Tokyo Electronics Co., Ltd.), and then heated at 205 ° C for 60 seconds to form a film. An anti-reflection film with a film thickness of 105 nm. The radiation sensitive resin composition of each of the examples and the comparative examples was applied onto the lower antireflection film using the above spin coater, and PB was carried out at 90 ° C for 60 seconds. Subsequently, it was cooled at 23 ° C for 30 seconds to form a resist film having a film thickness of 90 nm. Next, using an ArF excimer laser immersion exposure apparatus (NSR-S610C, manufactured by NIKON), with a line condition of NA=1.3, dipole (σ 0.977/0.782), a line and a spacer (1L1S) masked at 40 nm. The pattern exposes the resist film. After exposure, PEB was carried out at 90 ° C for 60 seconds. Subsequently, it was developed with a 2.38 mass% aqueous TMAH solution, washed with water, and dried to form a positive resist pattern.

<Evaluation>

The evaluation of each of the radiation sensitive resin compositions was carried out by measurement of each of the formed resist patterns. The results are shown in Table 2. Further, the measurement of the resist pattern formed by this method was carried out using a scanning electron microscope (S-9380, manufactured by Hitachi High-Technologies). For the LWR performance and the resolution, as a comparative example to be compared, Examples 27 to 34 are Comparative Example 1, Examples 23 and 24 are Comparative Example 2, and Example 22 is Comparative Example 3, and Examples 18 to 21 and 25 and 26 are Comparative Example 4. Further, "-" in Table 2 indicates a comparison object.

[LWR performance]

Using the scanning electron microscope, the resist pattern was observed from the upper portion of the pattern, and the line width of 50 points was measured at any point, and the value of the measured value was obtained to obtain a value of 3σ. Use this as LWR performance. The smaller the value, the better the LWR performance (nm). At this time, when compared with the comparative example, the LWR performance improvement of 10% or more (meaning that the value of the LWR performance is 0.9 times or less) can be evaluated as "good", and the LWR performance improvement of less than 10% is evaluated as " bad".

[resolution]

The size of the minimum resist pattern that is resolved in the above optimum exposure amount is taken as the resolution. The smaller the value, the better the resolution (nm). In this case, when the resolution of the comparative example is compared, when the resolution improvement of 10% or more is seen (meaning that the value of the resolution is 0.9 times or less), it can be evaluated as "good", and the solution is less than 10%. A person who is like an ascending person can be evaluated as "bad."

[Rectangularity of section shape]

Observing the cross-sectional shape of the resist pattern in which the above-mentioned optimum exposure amount is resolved, measuring the intermediate line width Lb of the resist pattern, the line width La of the upper portion of the film, and calculating the value of (La-Lb)/Lb. As an indicator of the squareness of the cross-sectional shape. The rectangular shape of the cross-sectional shape is closer to 1 at the value of (La-Lb)/Lb The better the expression. When the squareness of the cross-sectional shape is 0.9 ≦ (La-Lb) / Lb ≦ 1.1, it can be evaluated as "good", and when it is outside the range, it can be evaluated as "poor".

[Focus of depth]

Observing the size of the resist pattern in the above-mentioned optimum exposure amount image when the focus is changed in the depth direction, and entering the margin of the depth of 90% to 110% of the reference as the focus in the state of the state without the bridge or the residue. depth. The larger the value, the better the depth of focus (nm). When the depth of focus is compared with the comparative example, the increase in the depth of focus of 10% or more (meaning that the value of the depth of focus is 1.1 times or more) is evaluated as "good", and the improvement of the LWR performance of less than 10% is evaluated as "bad". .

(In the case of organic solvent imaging)

As shown in Table 1, each of the radiation sensitive resin compositions was prepared in the same composition as in Examples 18 to 34 and Comparative Examples 1 to 5. The developing solution was formed in the same manner as in Examples 18 to 34 and Comparative Examples 1 to 5 except that n-butyl acetate was used instead of 2.38 mass% of TMAH aqueous solution, and the formation and evaluation of the resist pattern were carried out. The results are shown together in Table 2.

As is apparent from the results of Table 2, the radiation sensitive resin composition of the present invention has excellent LWR properties, resolution, and cross-sectional shape rectangularity when exposed to AlF and organic solvent. And the depth of focus.

[Modulation of radiation-sensitive resin composition for electron beam exposure] [Example 35]

100 parts by mass of (A-3) as the [A] polymer, as [B] acid (S-1) 20 parts by mass of the generating agent, (C-1) 4,280 parts by mass as the [C] solvent, and 1,830 parts by mass of (C-2) and as the polymer of the [E] nitrogen atom (E- 1) 3.6 parts by mass of a modulating radiation-sensitive resin composition (J-18).

[Examples 36 to 51 and Comparative Example 6]

The radiation sensitive resin compositions (J-19) to (J-34) and (CJ-6) were prepared in the same manner as in Example 39 except that the components of the types and contents shown in Table 3 below were used. The "-" in Table 3 indicates that the component is not used.

<Formation of resist pattern>

The radiation sensitive resin composition was applied onto the surface of an 8-inch wafer using a spin coater (CLEAN TRACK ACT8, manufactured by Tokyo Electronics Co., Ltd.), and PB was applied at 90 ° C for 60 seconds. Subsequently, it was cooled at 23 ° C for 30 seconds to form a resist film having a film thickness of 50 nm. Next, the resist film was irradiated with an electron beam using a simple electron beam scanning device (HL800D, manufactured by Hitachi, Ltd., output: 50 KeV, current density: 5.0 amp/cm ² ). After the irradiation, PEB was performed at 130 ° C for 60 seconds. Subsequently, it was developed using a 2.38 mass% TMAH aqueous solution at 23 ° C for 30 seconds, washed with water, and dried to form a positive resist pattern. Each of the formed resist patterns was evaluated in the same manner as described above. The evaluation results are shown in Table 4. The LWR performance and the resolution were compared with Comparative Examples in Examples 35 to 51 as comparative examples to be compared. Further, "-" in Table 4 indicates a comparison object. The PEB of Comparative Example 6 was carried out at 90 ° C for 60 seconds.

As is clear from the results of Table 4, the radiation sensitive resin composition of the present invention is excellent in LWR performance, resolution, squareness of cross-sectional shape, and depth of focus when exposed to an electron beam and used for alkali development.

[Industrial availability]

According to the radiation-sensitive resin composition and the resist pattern forming method of the present invention, it is possible to form a resist pattern having a small LWR, a high resolution, and a high cross-sectional shape, while exhibiting a wide depth of focus. The radiation sensitive acid generator of the invention can be preferably used as It is a component of the radiation-sensitive resin composition. The compound of the present invention can be preferably used as the radiation-sensitive acid generator. According to the method for producing a compound of the present invention, the compound can be produced simply and in good yield. Accordingly, this can be preferably used in a manufacturing process or the like in a semiconductor device which is further miniaturized in the future.

Claims (12)

A radiation-sensitive resin composition comprising: an acid-dissociable group-containing polymer, a radiation-sensitive acid generator, and a solvent, wherein the radiation-sensitive acid generator comprises a compound represented by the following formula (1); 1] GLR ¹ -SO ₃ ^- M ⁺ (1) (In the formula (1), L is a group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S- or of at least one selected from a single bond, R ^A 1 ~ 20 of the monovalent hydrocarbon group is a hydrogen atom or a carbon atoms, and * represents a bonding site of G, L by _{-COO - *, - SO 2 O} -, - CONR When at least one selected from the group consisting of ^A -, -O-, and -S-, R ¹ is a substituted or unsubstituted carbon number of an unbonded fluorine atom adjacent to a carbon atom of SO ₃ ^- 10 alkanediyl, G is a cyclone structure having a carbon number of 3 to 30, a carboxyl group having a carbon number of 6 to 30, a heterocyclic structure having a carbon number of 3 to 30, or a carbon number 2 to 20 - NR ^B R ^C group, when L is a single bond, R ¹ is a single bond or a substituted or unsubstituted carbon number adjacent to the unbonded fluorine atom of the carbon atom of SO ₃ ^- the 10 alkanediyl group, G is as much as 7 to 30 carbon atoms, alicyclic hydrocarbon rings or -NR 2 ~ 20 carbon atoms is of the group ^B R ^C, R ^B, and R ^C Independently, it is an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms, or a ring structure having a ring number of 3 to 20 which is bonded to the nitrogen atoms bonded to the groups. M ⁺ is a monovalent radiation-decomposable cation cation). The radiation-sensitive resin composition of claim 1, wherein L in the above formula (1) is a group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S- At least one selected from the group consisting of R ^A being a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and R ¹ being a substituted or unsubstituted carbon number 1 of an unbonded fluorine atom adjacent to a carbon atom of SO ₃ ^- ~10 alkanediyl, G is a group having an alicyclic structure having a carbon number of 3 to 30. The radiation sensitive linear resin composition of claim 1, wherein L in the above formula (1) is a single bond, and R ¹ is a substituted or unsubstituted one of the unbonded fluorine atoms adjacent to the carbon atom of the SO ₃ ^- An alkanediyl group having 1 to 10 carbon atoms, and G is an alicyclic hydrocarbon group having a polycyclic number of 7 to 30 carbon atoms. A radiation-sensitive resin composition according to claim 1, which further comprises a radiation-sensitive acid generator other than the above-mentioned radiation-sensitive acid generator, and the radiation-sensitive acid generator is composed of a sulfonate compound, the sulfonate Two or more fluorine atoms are bonded to a carbon atom adjacent to -SO ₃ ^- in the acid ester compound. The radiation-sensitive resin composition of claim 4, wherein the acid-dissociable group-containing polymer has a structural unit represented by the following formula (2-1); (In the formula (2-1), R ³ is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, and Y ¹ is a monovalent acid dissociable group represented by the following formula (Y-1)), (In the formula (Y-1), R ^e1 is a monovalent chain hydrocarbon group having 1 to 10 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and R ^e2 and R ^{e3 are} each independently 1 to 10 carbon atoms. A valence chain hydrocarbon group or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or an alicyclic structure having 3 to 20 ring carbon atoms which are bonded to the bonded carbon atoms. The radiation-sensitive resin composition of claim 1, wherein the acid-dissociable group-containing polymer has a structural unit represented by the following formula (4). (In the formula (4), R ⁶ is a hydrogen atom or a methyl group, R ⁷ is a monovalent organic group, p is an integer of 0 to 3, and when R ⁷ is plural, plural R ⁷ may be the same or different. , q is an integer from 1 to 3, but p and q satisfy p+q≦5). The radiation sensitive resin composition of claim 6, which further comprises at least one selected from the group consisting of a nitrogen-containing compound and a compound which generates a carboxylic acid by irradiation with radiation. The radiation-sensitive resin composition of claim 1, wherein M ⁺ in the above formula (1) is a group consisting of a cation represented by the following formula (M-1) and a cation represented by the following formula (M-2) At least one selected from the group, (In the formula (M-1), R ¹¹ , R ¹² and R ^{13 are} each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, substituted or unsubstituted. An aromatic hydrocarbon group having 6 to 12 carbon atoms, -OSO ₂ -R ^D or -SO ₂ -R ^E , or a ring structure composed of two or more of these groups bonded together, and R ^D and R ^{E are} each independently A substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted alicyclic hydrocarbon group having 5 to 25 carbon atoms or a substituted or unsubstituted carbon number 6 to 12 aromatic hydrocarbon groups, k, m and n are each independently an integer of 0 to 5, and when R ¹¹ to R ¹³ and R ^D and R ^E are plural, respectively, a plurality of R ¹¹ to R ¹³ and R ^D are R ^E may be the same or different, and in the formula (M-2), R ¹⁴ and R ^{15 are} each independently substituted or unsubstituted, linear or branched alkyl having 1 to 12 carbon atoms, substituted. Or an unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, -OSO ₂ -R ^F or -SO ₂ -R ^G , or a ring structure in which two or more of the groups are bonded to each other, R ^F and R ^{G is} independently substituted or unsubstituted, linear or branched alkyl having 1 to 12 carbon atoms, substituted Or an unsubstituted alicyclic hydrocarbon group having 5 to 25 carbon atoms or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, and i and j are each independently an integer of 0 to 5, R ¹⁴ and R ¹⁵ When R ^F and R ^G are plural, respectively, a plurality of R ¹⁴ , R ¹⁵ , R ^F and R ^G may be the same or different. A resist pattern forming method having the steps of: forming a resist film by using a radiation-sensitive resin composition as claimed in claim 1, a step of exposing the resist film, and making the exposed film resistant The steps of etch imaging. A radiation sensitive acid generator consisting of a compound represented by the following formula (1), GLR ¹ -SO ₃ ^- M ⁺ (1) (in the formula (1), L is -COO At least one or a single bond selected from the group consisting of -*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, and R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. * indicates a bonding site with G, and L is at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, and R ¹ is adjacent a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms which is not bonded to a fluorine atom at a carbon atom of SO ₃ ^- , and a carbon group having a carbon number of 3 to 30 and having a carbon number of 6 a base of an aromatic ring structure of ~30, a group of a heterocyclic structure having a carbon number of 3 to 30 or a group of -NR ^B R ^{C having a} carbon number of 2 to 20, and when L is a single bond, R ¹ is a single bond or adjacency a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms which is not bonded to a fluorine atom at a carbon atom of SO ₃ ^- , and G is an alicyclic hydrocarbon group having a carbon number of 7 to 30 or a carbon number 2 to 20 -NR ^B R ^C group, R ^B and R ^{C are} each independently a C 1-10 alkyl group or a C 3-10 cycloalkyl group, or indicate that the groups are bonded to each other Bonded The number of ring membered ring structure of 3 to 20 constitutes together with the atoms, M ⁺ is a monovalent cation of radiation decomposable). A compound represented by the following formula (1), G7 ¹ -SO ₃ ^- M ⁺ (1) (in the formula (1), L is -COO-*, -SO ₂ O-, -CONR ^A At least one or a single bond selected from the group consisting of -, -O-, and -S-, and R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, * represents a bonding site with G, and L is When at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S-, R ¹ is an unbonded fluorine on a carbon atom adjacent to SO ₃ ^- A substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms, G is a group having an alicyclic structure having 3 to 30 carbon atoms, a group having an aromatic ring structure having a carbon number of 6 to 30, and a carbon number a group of 3 to 30 heterocyclic structures or a group having a carbon number of 2 to 20 -NR ^B R ^{C. When} L is a single bond, R ¹ is a single bond or is not bonded to a carbon atom adjacent to SO ₃ ^- A substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms, and G is a polycyclic alicyclic hydrocarbon group having 7 to 30 carbon atoms or a NR ^B R ^C group having 2 to 20 carbon atoms. R ^B and R ^{C are} each independently an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms, or a ring member number 3 in which the groups are bonded to each other and bonded to the nitrogen atom. Ring structure of ~20 The M ⁺ is a monovalent cation). A process for producing a compound represented by the following formula (1), which has a step of reacting an organic halide represented by the following formula (ia) with a sulfite represented by E ₂ SO _{3 to} obtain the following formula ( Ib) a step of indicating a sulfonate, and a step of reacting the above sulfonate with an onium salt represented by MY, (In the formulas (ia), (ib) and (1), L is at least one selected from the group consisting of -COO-*, -SO ₂ O-, -CONR ^A -, -O-, and -S- Or a single bond, R ^A is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, * represents a bonding site with G, and L is a group of -COO-*, -SO ₂ O-, -CONR ^A -, -O When at least one selected from the group consisting of - and -S-, R ¹ is a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms adjacent to an unbonded fluorine atom on a carbon atom of SO ₃ ^- , G is a base of an alicyclic structure having a carbon number of 3 to 30, a base of an aromatic ring having a carbon number of 6 to 30, a base of a heterocyclic structure having a carbon number of 3 to 30, or a carbon number of 2 to 20 - a group of NR ^B R ^C , when L is a single bond, R ¹ is a single bond or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms adjacent to a fluorine atom not bonded to a carbon atom of SO ₃ ^- , G is an alicyclic hydrocarbon group having a carbon number of 7 to 30 or a NR ^B R ^C group having a carbon number of 2 to 20, and R ^B and R ^{C are} each independently an alkyl group having 1 to 10 carbon atoms or carbon. a cycloalkyl group of 3 to 10, or a ring structure of 3 to 20 ring members which are bonded to the nitrogen atoms bonded to the groups, X is a halogen atom, and E ⁺ is an alkali metal ion. M ⁺ is a monovalent radiation Decomposable cation, Y ^- is a monovalent anion).