JP2017173420A - Radiation-sensitive composition and pattern formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation-sensitive composition that can exhibit excellent sensitivity when EUV light or the like having a wavelength of 250 nm or less is used as pattern exposure light.SOLUTION: The radiation-sensitive composition includes: a polymer having a structural unit including an acid-dissociable group; a sensitizer precursor which generates a sensitizer absorbing a first radiation having a wavelength of more than 250 nm by light exposure; a metal-containing compound; and a solvent. In the radiation-sensitive composition, the sensitizer precursor includes at least one of the following components (a) and (b): (a) a radiation-sensitive acid-sensitizer generating body which generates an acid and the above-mentioned sensitizer when irradiated with a second radiation having a wavelength of 250 nm or less and not irradiated with the above-mentioned first radiation; and (b) a radiation-sensitive sensitizer generating body which generates the sensitizer when irradiated with the above-mentioned second radiation and not emitting the first radiation.SELECTED DRAWING: None

Description

  The present invention relates to a radiation-sensitive composition and a pattern forming method.

  EUV (extreme ultraviolet light) lithography has attracted attention as one of elemental technologies for manufacturing next-generation semiconductor devices. EUV lithography is a pattern formation technique that uses EUV light having a wavelength of 13.5 nm as an exposure light source. According to EUV lithography, it has been demonstrated that an extremely fine pattern (for example, 20 nm or less) can be formed in the exposure step of the semiconductor device manufacturing process.

  However, since the EUV light source currently developed has a low output, it takes a long time for the exposure process. Therefore, EUV lithography has a disadvantage that it is not practical. In response to this inconvenience, a technique for improving the sensitivity of the radiation-sensitive composition (resist composition) has been developed (see JP-A-2002-174894).

  However, even the radiation-sensitive composition in the above technique has insufficient sensitivity to EUV light. This inconvenience also exists when an electron beam or the like is used as irradiation light.

JP 2002-174894 A

  The present invention has been made on the basis of the above-mentioned circumstances, and the object thereof is ionizing radiation such as EUV light, electron beam, ion beam or the like having a wavelength of 250 nm or less, or non-radiation such as KrF excimer laser and ArF excimer laser. An object of the present invention is to provide a radiation-sensitive composition capable of exhibiting excellent sensitivity when ionizing radiation is used as pattern exposure light, and a pattern forming method using the radiation-sensitive composition.

The invention made to solve the above problems is a polymer having a structural unit containing an acid-dissociable group (hereinafter also referred to as “structural unit (I)”) (hereinafter also referred to as “[A] polymer”). And a sensitizer precursor (hereinafter referred to as “[B] sensitizer precursor”) that generates a sensitizer that absorbs first radiation (hereinafter also referred to as “radiation (I)”) having a wavelength exceeding 250 nm by exposure. ), A metal-containing compound (hereinafter also referred to as “[C] metal-containing compound”), and a solvent (hereinafter also referred to as “[D] solvent”). The body precursor is a radiation-sensitive composition containing at least one of the following components (a) and (b).
(A) When the second radiation (hereinafter also referred to as “radiation (II)”) having a wavelength of 250 nm or less is irradiated and the radiation (I) is not irradiated, an acid and the sensitizer are generated, and A radiation-sensitive acid-sensitizer generator (b) that does not substantially generate the acid and sensitizer when irradiated with only the radiation (I) without irradiation with radiation (II). The sensitizer is generated when irradiated and does not emit the radiation (I), and the sensitizer is substantially generated when only the radiation (I) is irradiated without irradiating the radiation (II). Does not cause radiation-sensitive sensitizer

The invention made to solve the above problems includes a film forming step of forming a film using the radiation-sensitive composition on at least one surface of a substrate, and irradiating the film with radiation having a wavelength of 250 nm or less. A pattern exposure step, a batch exposure step of irradiating the film after the pattern exposure step with radiation having a wavelength of more than 250 nm, a baking step of heating the film after the batch exposure step, and a post-bake step And a development step of bringing the film into contact with a developer.

  Here, “when the radiation (II) is not irradiated and only the radiation (I) is irradiated, the acid and the sensitizer are not substantially generated”, “the radiation (II) is not irradiated and only the radiation (I) is not irradiated. The above-mentioned sensitizer is not substantially generated when irradiated with "I" means that acid or sensitizer is not generated by irradiation with radiation (I), or acid or sensitizer by irradiation with radiation (I). Even when this occurs, the difference in the concentration of the acid and the sensitizer between the exposed portion and the non-exposed portion in the pattern exposure that irradiates the radiation (I) can be maintained to a size that allows pattern formation. The amount of acid and sensitizer in the non-exposed area in the pattern exposure due to radiation (I) is small, and as a result, only either the exposed or non-exposed area in the pattern exposure is dissolved in the developer after development. As little acid and sensitizer as possible Means that no.

  When the radiation-sensitive composition of the present invention uses ionizing radiation such as EUV light having a wavelength of 250 nm or less, electron beam, ion beam, or non-ionizing radiation such as KrF excimer laser and ArF excimer laser as pattern exposure light. It is possible to exhibit excellent sensitivity. Moreover, the said radiation sensitive composition can be used suitably for the said pattern formation method.

It is process drawing which shows one Embodiment of the pattern formation method using the radiation sensitive composition which concerns on this invention. It is process drawing which shows an example of the pattern formation method using the conventional radiation sensitive composition. It is process drawing which shows another embodiment of the pattern formation method using the radiation sensitive composition which concerns on this invention. It is a conceptual diagram which shows the light absorbency of the pattern exposure part of a film | membrane, and the light absorbency of an unexposed part as a graph. (A) is a conceptual diagram which shows the acid concentration distribution by the pattern formation method using the conventional radiation sensitive composition as a graph. (B) is a conceptual diagram showing the sensitizer concentration distribution and the acid concentration distribution by a pattern forming method using the radiation-sensitive composition according to the present embodiment as a graph. It is sectional drawing explaining an example of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention, (a) is sectional drawing which shows a pattern formation process, (b) is sectional drawing which shows an etching process, (C) is sectional drawing which shows a pattern removal process.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, this invention is not limited to the following embodiment.

<Radiation sensitive composition>
The radiation-sensitive composition contains a [A] polymer, a [B] sensitizer precursor, a [C] metal-containing compound, and a [D] solvent, and the [B] sensitizer precursor. The body contains at least one of the following components (a) and (b).
(A) When radiation (II) having a wavelength of 250 nm or less is irradiated and the radiation (I) is not irradiated, the acid and the sensitizer are generated, and the radiation (II) is not irradiated and the radiation (II) I) A radiation-sensitive acid-sensitizer generator that does not substantially generate the acid and sensitizer when irradiated only (b) When the radiation (II) is irradiated and the radiation (I) is not emitted A radiation-sensitive sensitizer that does not substantially generate the sensitizer when irradiated with only the radiation (I) without irradiation with the radiation (II)

  The radiation-sensitive composition contains a [C] metal-containing compound in addition to the [A] polymer and [B] sensitizer precursor, so that EUV light of 250 nm or less, electron beam, ion beam, etc. It is possible to exhibit excellent sensitivity when ionizing radiation or non-ionizing radiation such as KrF excimer laser and ArF excimer laser is used as pattern exposure light. The reason why the radiation-sensitive composition exhibits the above-described effect by having the above-described configuration is not necessarily clear, but can be inferred as follows, for example. That is, the absorption (absorption wavelength and / or absorbance) of the radiation (I) of the sensitizer generated from the [B] sensitizer precursor by the action of the acid generated by the pattern exposure light by irradiation with the radiation (II) is [ C] It is considered to change due to interaction with the metal-containing compound. Thereby, the absorption of the radiation (I) by the sensitizer in the batch exposure step can be increased, and as a result, the amount of acid generated in the batch exposure step increases, and thus the sensitivity of the radiation-sensitive composition. Can be increased.

  The radiation-sensitive composition further contains a [E] radiation-sensitive acid generator in addition to the [A] polymer, the [B] sensitizer precursor, the [C] metal-containing compound and the [D] solvent. It is preferable that an acid diffusion control agent, a radical scavenger, a crosslinking agent, other polymers, other additives, and the like may be further included.

  Here, the [B] sensitizer precursor may be incorporated in a part of the [A] polymer, or may be a component different from the [A] polymer. In this case, even if a part of the [B] sensitizer precursor is a component different from the [A] polymer, the whole [B] sensitizer precursor is a component different from the [A] polymer. Also good.

[[A] polymer]
[A] The polymer is a polymer having the structural unit (I). The structural unit (I) is a structural unit containing an acid dissociable group. An “acid-dissociable group” is a group that generates a polar group by the action of an acid. [A] Since the polymer has an acid dissociable group, it becomes soluble or insoluble in the developer by the action of an acid.

  [A] The polymer is a structural unit containing a fluorine atom (hereinafter, also referred to as “structural unit (II)”), a structural unit (III) containing a phenolic hydroxyl group, and a lactone structure, a cyclic carbonate structure, a sultone structure, or these The structural unit (IV) including a combination may be further included, and other structural units other than the structural units (I) to (IV) may be further included. Hereinafter, each structural unit will be described.

(Structural unit (I))
The structural unit (I) is a structural unit containing an acid dissociable group. [A] When the polymer has the structural unit (I), the radiation-sensitive composition can form a pattern with excellent resolution. Examples of the structural unit (I) include a structural unit represented by the following formula (a-1) (hereinafter also referred to as “structural unit (I-1)”), and a structure represented by the following formula (a-2). A unit (hereinafter also referred to as “structural unit (I-2)”). In the following formulas (a-1) and (a-2), groups represented by —CR ^A2 R ^A3 R ^A4 and —CR ^A6 R ^A7 R ^A8 are acid dissociable groups.

In the above formula (a-1), R ^A1 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R ^A2 is a monovalent hydrocarbon group having 1 to 20 carbon atoms. R ^A3 and R ^A4 each independently represent a monovalent hydrocarbon group having 1 to 20 carbon atoms, or have 3 to 20 ring members formed together with carbon atoms to which these groups are combined with each other. Represents an alicyclic structure.
In the above formula (a-2), R ^A5 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R ^A6 is a hydrogen atom, a monovalent hydrocarbon group having 1 to 20 carbon atoms, or a monovalent oxyhydrocarbon group having 1 to 20 carbon atoms. R ^A7 and R ^A8 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms or a monovalent oxyhydrocarbon group having 1 to 20 carbon atoms. L ^A is a single bond, -O -, - COO- or -CONH-.

Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms represented by the above R ^A2 , R ^A3 , R ^A4 , R ^A6 , R ^A7 and R ^A8 include a chain hydrocarbon group having 1 to 30 carbon atoms, A C3-C30 alicyclic hydrocarbon group, a C6-C30 aromatic hydrocarbon group, etc. are mentioned.

Examples of the monovalent chain hydrocarbon group having 1 to 30 carbon atoms include alkyl groups such as a methyl group, an ethyl group, an n-propyl group, and an i-propyl group;
An alkenyl group such as an ethenyl group, a propenyl group, a butenyl group;
Examples thereof include alkynyl groups such as ethynyl group, propynyl group and butynyl group.

Examples of the monovalent alicyclic hydrocarbon group having 3 to 30 carbon atoms include a saturated simple group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclopentyl group, a cyclooctyl group, a cyclodecyl group, and a cyclododecyl group. A cyclic hydrocarbon group;
Unsaturated monocyclic hydrocarbon groups such as cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, cyclohexenyl group, cyclooctenyl group, cyclodecenyl group;
Saturated polycyclic hydrocarbon groups such as bicyclo [2.2.1] heptanyl group, bicyclo [2.2.2] octanyl group, tricyclo [3.3.1.1 ^3,7 ] decanyl group;
And unsaturated polycyclic hydrocarbon groups such as a bicyclo [2.2.1] heptenyl group and a bicyclo [2.2.2] octenyl group.

Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include aryl groups such as phenyl group, tolyl group, xylyl group, mesityl group, naphthyl group, methylnaphthyl group, anthryl group, and methylanthryl group;
Examples thereof include aralkyl groups such as benzyl group, phenethyl group, naphthylmethyl group and anthrylmethyl group.

R ^A2 is preferably a chain hydrocarbon group and a cycloalkyl group, more preferably an alkyl group and a cycloalkyl group, and a methyl group, an ethyl group, a propyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, and an adamantyl group. Further preferred.

Examples of the alicyclic structure having 3 to 20 ring members composed of the R ^A3 and R ^A4 groups together with the carbon atom to which they are bonded include a cyclopropane structure, a cyclobutane structure, a cyclopentane structure, a cyclopentene structure, a cyclopentane structure, and the like. Monocyclic cycloalkane structures such as pentadiene structure, cyclohexane structure, cyclooctane structure, cyclodecane structure;
Examples thereof include polycyclic cycloalkane structures such as a norbornane structure, an adamantane structure, a tricyclodecane structure, and a tetracyclododecane structure.

As R ^A3 and R ^A4 , an alkyl group, a monocyclic cycloalkane structure, a norbornane structure, and an adamantane structure constituted by combining these groups are preferable, and a methyl group, an ethyl group, a cyclopentane structure, a cyclohexane structure, and An adamantane structure is more preferred.

Examples of the monovalent oxyhydrocarbon group having 1 to 20 carbon atoms represented by R ^A6 , R ^A7 and R ^A8 include, for example, carbons of R ^A2 , R ^A3 , R ^A4 , R ^A6 , R ^A7 and R ^A8 . Examples of the monovalent hydrocarbon group having 1 to 20 include groups containing an oxygen atom at the terminal on the bond side.

R ^A6 , R ^A7 and R ^A8 are preferably a chain hydrocarbon group and an oxyalicyclic hydrocarbon group.

As the ^{L A,} a single bond and -COO- is more preferably a single bond.

R ^A1 is preferably a hydrogen atom and a methyl group, more preferably a methyl group, from the viewpoint of copolymerization of the monomer that gives the structural unit (I).

R ^A5 is preferably a hydrogen atom and a methyl group, and more preferably a hydrogen atom, from the viewpoint of copolymerization of the monomer that gives the structural unit (I).

  Examples of the structural unit (I-1) include structural units represented by the following formulas (a-1-a) to (a-1-d) (hereinafter referred to as “structural units (I-1-a) to (I -1-d) ”) and the like. Examples of the structural unit (I-2) include a structural unit represented by the following formula (a-2-a) (hereinafter also referred to as “structural unit (I-2-a)”).

In the formulas (a-1-a) to (a-1-d), R ^{A1 to} R ^A4 have the same meanings as the formula (a-1). n _a is an integer of 1 to 4. In the above formula (a-2-a), R ^{A5 to} R ^A8 have the same ^meanings as the above formula (a-2).

The n _a, preferably 1, 2 and 4, more preferably 1.

  Examples of the structural units (I-1-a) to (I-1-d) include structural units represented by the following formulas.

In the above formula, R ^A1 has the same ^meaning as the above formula (a-1).

  Examples of the structural unit (I-2) include a structural unit represented by the following formula.

In the above formula, R ^A5 has the same ^{meaning as} in the above formula (a-2).

  As the structural unit (I), structural units (I-1-a) to (I-1-d) are preferable, and a structural unit derived from 2-methyl-2-adamantyl (meth) acrylate, 2-ipropyl-2 -Structural unit derived from adamantyl (meth) acrylate, structural unit derived from 1-methyl-1-cyclopentyl (meth) acrylate, structural unit derived from 1-ethyl-1-cyclohexyl (meth) acrylate, 1-ipropyl Structural units derived from -1-cyclopentyl (meth) acrylate, structural units derived from 2-cyclohexylpropan-2-yl (meth) acrylate, and 2- (adamantan-1-yl) propan-2-yl (meth) A structural unit derived from acrylate is more preferred.

  [A] As a minimum of the content rate of structural unit (I) with respect to all the structural units which constitute a polymer, 10 mol% is preferred, 20 mol% is more preferred, 25 mol% is still more preferred, and 30 mol% is especially preferable. On the other hand, the upper limit of the content is preferably 80 mol%, more preferably 70 mol%, further preferably 65 mol%, particularly preferably 60 mol%. By setting the content ratio within the above range, it is possible to sufficiently ensure the dissolution contrast of the pattern-exposed portion and the non-exposed portion of the film formed from the radiation-sensitive composition with respect to the developer. Image properties and the like are improved.

(Structural unit (II))
The structural unit (II) is a structural unit containing a fluorine atom (except for those corresponding to the structural unit (I)). The structural unit (II) usually does not contain a salt structure. Examples of the structural unit (II) include structural units represented by the following formulas (f-1) to (f-4).

In said formula (f-1), R ^<F1> is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. L ^F1 is a single bond, an oxygen atom, a sulfur atom, —CO—O—, —SO ₂ —O—NH—, —CO—NH—, or —O—CO—NH—. R ^F2 is a monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms.
In said formula (f-2), R ^<F3> is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. L ^F2 is a single bond, an oxygen atom, a sulfur atom, —CO—O—, —SO ₂ —O—NH—, —CO—NH—, or —O—CO—NH—. R ^F4 is a single bond, a (u + 1) -valent hydrocarbon group having 1 to 20 carbon atoms, or an oxygen atom, a sulfur atom, —NR ^FF1 —, a carbonyl group, —CO at the terminal of R ^F5 side of this hydrocarbon group. A structure in which —O— or —CO—NH— is bonded. R ^FF1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. R ^F5 is a single bond or a divalent organic group having 1 to 20 carbon atoms. L ^F3 is a single bond or a divalent fluorinated chain hydrocarbon group having 1 to 20 carbon atoms. A ¹ is an oxygen atom, —NR ^FF2 —, —CO—O— *, or —SO ₂ —O— *. R ^FF2 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. * Indicates a site that binds to R ^F6 . R ^F6 is a hydrogen atom or a monovalent organic group having 1 to 30 carbon atoms. u is an integer of 1 to 3. However, when u is 1, R ^F4 may be a single bond. When u is 2 or 3, a plurality of R ^F5 may be the same or different, a plurality of L ^F3 may be the same or different, a plurality of A ¹ may be the same or different, and a plurality of R ^F6 may be the same or different.
In formula (f-3), R ^F7 represents a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, or a monovalent carbonyloxy hydrocarbon group having 2 to 20 carbon atoms. L ^F4 is a single bond, an oxygen atom, a sulfur atom, —CO—O—, —SO ₂ —O—NH—, —CO—NH—, or —O—CO—NH—. R ^F8 is a single bond or a divalent organic group having 1 to 20 carbon atoms. R ^F9 and R ^F10 are each independently an alkyl group having 1 to 10 carbon atoms or a fluorinated alkyl group having 1 to 10 carbon atoms. However, one of R ^F9 and R ^F10 is a fluorinated alkyl group. v is an integer of 1 to 3. When v is 2 or 3, a plurality of R ^F9 may be the same or different, and a plurality of R ^F10 may be the same or different.
In said formula (f-4), R ^<F11> is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R ^F12 and R ^F13 are each independently a hydrogen atom, a halogen atom, a hydroxy group, or a monovalent organic group having 1 to 20 carbon atoms. w is an integer of 1-4. When w is 2 or more, the plurality of R ^F12 may be the same or different, and the plurality of R ^F13 may be the same or different. Two or more of one or more of R ^F12 and one or more of R ^F13 form a ring structure having 3 to 20 ring members that is combined with a carbon atom or a carbon chain to which they are bonded together. Also good. R ^F14 and R ^F15 are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. However, at least one of R ^F14 and R ^F15 is a monovalent organic group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom. R ^F14 and R ^F15 may be combined with each other to form a ring structure with 3 to 20 ring members that is configured together with the carbon atom to which they are bonded.

As said R ^{<F1 >} , R ^{< F3>} and R ^<F11> , a hydrogen atom and a methyl group are preferable and a methyl group is more preferable. As R ^F7 , a hydrogen atom, a methyl group, and a monovalent carbonyloxy hydrocarbon group are preferable, a methyl group and an alkoxycarbonyl group are more preferable, and a methyl group and an ethoxycarbonyl group are further preferable.

As said L ^<F1> , L ^<F2> and L ^<F4> , a single bond, an oxygen atom, and -CO-O- are preferable, and -CO-O- is more preferable.

The monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms represented by R ^F2, replacing part or all of the hydrogen atoms included in the monovalent hydrocarbon group having 1 to 20 carbon atoms with a fluorine atom The thing which was done is mentioned. Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include groups similar to those exemplified for the above R ^A2 , R ^A6 , R ^A7 and R ^A8 .

As R ^F2 , a fluorinated chain hydrocarbon group is preferable, a fluorinated alkyl group is more preferable, and a fluorinated methyl group and a fluorinated ethyl group are further preferable.

Examples of the (u + 1) -valent hydrocarbon group having 1 to 20 carbon atoms represented by R ^F4 include monovalent carbon atoms having 1 to 20 carbon atoms exemplified by R ^A2 , R ^A6 , R ^A7 and R ^A8. Examples include those obtained by further removing u hydrogen atoms from a hydrogen group.

As said ^RFF1 , a hydrogen atom and a C1-C10 alkyl group are preferable, and a hydrogen atom, a methyl group, and an ethyl group are more preferable.

As R ^F4 , a single bond, a (u + 1) -valent chain hydrocarbon group having 1 to 20 carbon atoms, and an (u + 1) -valent aromatic hydrocarbon group having 6 to 20 carbon atoms are preferable. A (u + 1) -valent chain hydrocarbon group having 1 to 10 carbon atoms and a (u + 1) -valent chain hydrocarbon group having 6 to 10 carbon atoms are more preferable.

Examples of the divalent organic group having 1 to 20 carbon atoms represented by R ^F5 and R ^F8 include a divalent hydrocarbon group, divalent at the carbon-carbon end of the hydrocarbon group or at the terminal on the bond side. Groups containing a heteroatom-containing group, a group in which part or all of the hydrogen atoms of these groups are substituted with a substituent, and the like.

Examples of the divalent hydrocarbon group having 1 to 20 carbon atoms include alkanediyl groups such as methanediyl group, ethanediyl group, propanediyl group, and butanediyl group;
Alkenediyl groups such as ethenediyl group, propenediyl group, butenediyl group;
Chain hydrocarbon groups such as alkynediyl groups such as ethynediyl, propynediyl, butynediyl;
Monocyclic cycloalkanediyl groups such as cyclopropanediyl group, cyclobutanediyl group, cyclopentanediyl group, cyclohexanediyl group;
Monocyclic cycloalkenediyl groups such as cyclopropenediyl group and cyclobutenediyl group;
A polycyclic cycloalkanediyl group such as a norbornanediyl group, an adamantanediyl group, a tricyclodecanediyl group, a tetracyclododecanediyl group;
An alicyclic hydrocarbon group such as a polycyclic cycloalkenediyl group such as a norbornenediyl group or a tricyclodecenediyl group;
Arenediyl groups such as benzenediyl group, toluenediyl group, xylenediyl group, naphthalenediyl group;
Aromatic hydrocarbon groups such as arenediyl (cyclo) alkanediyl groups such as benzenediylmethanediyl group and naphthalenediylcyclohexanediyl group.

  The hetero atom-containing group refers to a group having a divalent or higher valent hetero atom in the structure. The hetero atom-containing group may have one hetero atom or two or more hetero atoms. Here, the “hetero atom” refers to an atom other than a hydrogen atom and a carbon atom. The hetero atom-containing group may have only a hetero atom.

  The divalent or higher valent hetero atom of the hetero atom-containing group is not particularly limited as long as it is a hetero atom having a valence of 2 or higher. For example, an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom And boron atoms.

Examples of the hetero atom-containing group include —O—, —S—, —NR ^HE —, —PR ^HE —, —SO—, —SO ₂ —, —SO ₂ O—, —OPO (OR ^HE ) O—. ^{_{, -PO 2 -, - PO 2}} O -, - CO -, - COO -, - COS -, - CONR HE -, - OCOO -, - OCOS -, - OCONR HE -, - SCONR HE -, - SCSNR HE -, -SCSS- group, etc. are mentioned. Here, R ^HE is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms.

  Examples of the substituent include halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom, hydroxy group, carboxy group, nitro group and cyano group.

R ^F5 and R ^F8 are preferably a single bond, a divalent hydrocarbon group having 1 to 20 carbon atoms, and a group containing an oxygen atom between carbon-carbon atoms of the divalent hydrocarbon group. A divalent chain hydrocarbon group having 1 to 20 and a group containing an oxygen atom between carbon and carbon of the divalent chain hydrocarbon group and a divalent aromatic hydrocarbon group having 1 to 20 carbon atoms are more preferable. More preferred are a single bond, an alkanediyl group, an alkanediyloxyalkanediyl group and an arenediyl group.

Examples of the divalent fluorinated chain hydrocarbon group having 1 to 20 carbon atoms represented by L ^F3 include one of hydrogen atoms possessed by the divalent chain hydrocarbon group exemplified by the above R ^F5 and R ^F8. Examples include groups in which part or all are substituted with fluorine atoms.

As said ^LF3 , a single bond and a C1-C10 bivalent fluorinated chain hydrocarbon group are preferable, and a single bond and a C1-C10 fluorinated alkanediyl group are more preferable.

The above-mentioned ^{A 1,} oxygen atom and -CO-O- are preferable.

As said ^RFF2 , a hydrogen atom and a C1-C10 alkyl group are preferable, and a hydrogen atom, a methyl group, and an ethyl group are more preferable.

Examples of the monovalent organic group having 1 to 20 carbon atoms represented by R ^F6 , R ^F12 , R ^F13 , R ^F14, and R ^F15 include a monovalent hydrocarbon group and a carbon-carbon bond of the hydrocarbon group. Alternatively, a group containing a divalent heteroatom-containing group at the terminal on the bond side, a group in which part or all of the hydrogen atoms of these groups are substituted with a substituent, and the like can be given.

Examples of the monovalent hydrocarbon group include the same groups as those exemplified for R ^A2 , R ^A6 , R ^A7 and R ^A8 . Examples of the heteroatom-containing group and substituent include the same groups as those exemplified for R ^F5 and R ^F8 above.

As R ^F6 , a hydrogen atom and a monovalent chain hydrocarbon group having 1 to 30 carbon atoms are preferable, a hydrogen atom and an alkyl group having 1 to 30 carbon atoms are more preferable, and a hydrogen atom and an alkyl group having 1 to 10 carbon atoms are preferable. More preferred is an alkyl group. However, when L ^F3 is a single bond, R ^F6 preferably has a fluorine atom.

R ^F12 and R ^F13 are preferably a hydrogen atom and a monovalent hydrocarbon group having 1 to 12 carbon atoms, more preferably a monovalent hydrocarbon group having 1 to 12 carbon atoms, a phenyl group, a cycloalkyl group, And a fluorine atom-containing alkyl group substituted with a hydroxy group is more preferable.

R ^F14 and R ^F15 are preferably a hydrogen atom, a monovalent hydrocarbon group having 1 to 12 carbon atoms, and a monovalent hydroxy-substituted fluorinated hydrocarbon group having 3 to 12 carbon atoms. ˜12 alkyl groups and C 3-12 hydroxyfluorinated alkyl groups are more preferred, and hydrogen atom, methyl group, ethyl group and hydroxydi (trifluoromethyl) ethyl group are more preferred.

R ^F9 and R ^F10 are preferably a methyl group, an ethyl group, a propyl group, a fluorinated methyl group, a fluorinated ethyl group and a fluorinated propyl group, more preferably a fluorinated methyl group and a fluorinated ethyl group, and a fluorinated group. A methyl group is more preferable, and a trifluoromethyl group is particularly preferable.

  As said u, 1 and 2 are preferable and 1 is more preferable. As said v, 1 and 2 are preferable and 1 is more preferable. As said w, 1 and 2 are preferable and 1 is more preferable.

  As the structural unit (II), a structural unit represented by the following formula is preferred.

In the above formula, R ^F1 has the same ^meaning as the above formula (f-1). R ^F7 has the same ^{meaning as} in the above formula (f-3).

  [A] When the polymer has the structural unit (II), the lower limit of the content ratio of the structural unit (II) to all structural units constituting the [A] polymer is preferably 3 mol%, and 5 mol% More preferred is 10 mol%. On the other hand, as an upper limit of the said content rate, 40 mol% is preferable, 35 mol% is more preferable, and 30 mol% is further more preferable. By making the said content rate into the said range, the sensitivity in case EUV etc. are used as pattern exposure light can be improved more. On the other hand, when the said content rate exceeds the said upper limit, there exists a possibility that the rectangularity in the cross-sectional shape of a pattern may fall.

(Structural unit (III))
The structural unit (III) is a structural unit containing a phenolic hydroxyl group (except for those corresponding to the structural unit (I) and the structural unit (II)). [A] When the polymer has the structural unit (III), the sensitivity in the case of irradiation with KrF excimer laser light, EUV (extreme ultraviolet), an electron beam, or the like can be further improved in the pattern exposure step described later.

Part or all of the hydrogen atoms of the aromatic ring containing the phenolic hydroxyl group may be substituted with a substituent. Examples of this substituent include the same groups as those exemplified for R ^F5 and R ^F8 above.

  Examples of the structural unit (III) include structural units represented by the following formulas (h-1) to (h-6) (hereinafter also referred to as “structural units (III-1) to (III-6)”). Can be mentioned.

In the above formulas (h-1) to (h-6), R ^AF1 is a hydrogen atom or a methyl group.

As said ^RAF1 , a hydrogen atom is preferable.

  As the structural unit (III), structural units (III-1) and (III-2) are preferable, and (III-1) is more preferable.

  [A] When the polymer has the structural unit (III), the lower limit of the content ratio of the structural unit (III) with respect to all the structural units constituting the [A] polymer is preferably 1 mol%, preferably 30 mol%. More preferred is 50 mol%. On the other hand, as an upper limit of the said content rate, 90 mol% is preferable, 80 mol% is more preferable, and 75 mol% is further more preferable. By making the content rate of structural unit (III) into the said range, the sensitivity of the said radiation sensitive composition can be improved more.

  The structural unit (III) is obtained by polymerizing a monomer in which a hydrogen atom of an —OH group of an aromatic ring containing a phenolic hydroxyl group is substituted with an acetyl group, and then hydrolyzing the obtained polymer in the presence of an amine. It can be formed by a reaction method or the like.

(Structural unit (IV))
The structural unit (IV) is a structural unit containing a lactone structure, a cyclic carbonate structure, a sultone structure, or a combination thereof (except for those corresponding to the structural unit (I) to the structural unit (III)). [A] Since the polymer further has the structural unit (IV), the solubility in the developer can be adjusted to a more appropriate one, and as a result, the lithography performance of the radiation-sensitive composition can be further improved. Can be improved. Moreover, the adhesiveness of the film | membrane formed from the said radiation sensitive composition and a board | substrate can be improved. Here, the lactone structure refers to a structure having one ring (lactone ring) including a group represented by —O—C (O) —. The cyclic carbonate structure refers to a structure having one ring (cyclic carbonate ring) including a group represented by —O—C (O) —O—. The sultone structure refers to a structure having one ring (sultone ring) including a group represented by —O—S (O) ₂ —. Examples of the structural unit (III) include a structural unit represented by the following formula.

In the above formula, R ^AL is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

As said ^RAL , a hydrogen atom and a methyl group are preferable from the viewpoint of the copolymerizability of the monomer which gives structural unit (IV), and a methyl group is more preferable.

  As the structural unit (IV), among these, a structural unit containing a norbornane lactone structure, a structural unit containing an oxanorbornane lactone structure, a structural unit containing a γ-butyrolactone structure, a structural unit containing an ethylene carbonate structure, and norbornane sultone A structural unit containing a structure is preferable, a structural unit derived from norbornanelactone-yl (meth) acrylate, a structural unit derived from oxanorbornanelactone-yl (meth) acrylate, and a cyano-substituted norbornanelactone-yl (meth) acrylate Structural unit, structural unit derived from norbornanelactone-yloxycarbonylmethyl (meth) acrylate, structural unit derived from butyrolactone-3-yl (meth) acrylate, butyrolactone-4-yl (meth) acrylate A structural unit derived from 3,5-dimethylbutyrolactone-3-yl (meth) acrylate, a structural unit derived from 4,5-dimethylbutyrolactone-4-yl (meth) acrylate, 1- (butyrolactone) -3-yl) cyclohexane-1-yl (meth) acrylate-derived structural unit, ethylene carbonate-ylmethyl (meth) acrylate-derived structural unit, cyclohexene carbonate-ylmethyl (meth) acrylate-derived structural unit, norbornane sultone -A structural unit derived from yl (meth) acrylate and a structural unit derived from norbornane sultone-yloxycarbonylmethyl (meth) acrylate are more preferred.

  [A] When the polymer has a structural unit (IV), the lower limit of the content ratio of the structural unit (IV) to all structural units constituting the [A] polymer is preferably 1 mol%, and 10 mol% More preferably, 20 mol% is more preferable, and 25 mol% is particularly preferable. On the other hand, the upper limit of the content is preferably 70 mol%, more preferably 65 mol%, still more preferably 60 mol%, and particularly preferably 55 mol%. By making the said content rate into the said range, the adhesiveness of the film | membrane formed from the said radiation sensitive composition and a board | substrate can be improved more.

[Other structural units]
[A] The polymer may have other structural units in addition to the structural units (I) to (IV). Examples of other structural units include a structural unit containing a polar group and a structural unit containing a non-dissociable hydrocarbon group. Examples of the polar group include an alcoholic hydroxyl group, a carboxy group, a cyano group, a nitro group, and a sulfonamide group. Examples of the non-dissociable hydrocarbon group include a linear alkyl group. [A] As an upper limit of the content rate of the said other structural unit with respect to all the structural units which comprise a polymer, 20 mol% is preferable and 10 mol% is more preferable.

  [A] As a minimum of content of a polymer, 70 mass% is preferable in the total solid of the said radiation sensitive composition, 75 mass% is more preferable, 80 mass% is further more preferable. Here, “total solid content” refers to components other than the solvent of the radiation-sensitive composition.

  [A] The weight average molecular weight (Mw) in terms of polystyrene by gel permeation chromatography (GPC) of the polymer is not particularly limited, but the lower limit thereof is preferably 1,000, more preferably 2,000, and 3,000. Is more preferable, and 5,000 is particularly preferable. On the other hand, the upper limit of the Mw of the [A] polymer is preferably 50,000, more preferably 30,000, still more preferably 20,000, and particularly preferably 15,000. [A] By making Mw of a polymer into the said range, the applicability | paintability and development defect inhibitory property of the said radiation sensitive composition improve. [A] When Mw of the polymer is smaller than the lower limit, a film having sufficient heat resistance may not be obtained. Conversely, when the Mw of the [A] polymer exceeds the above upper limit, the developability of the film may be reduced.

  [A] The lower limit of the ratio (Mw / Mn) of Mw to the number average molecular weight (Mn) in terms of polystyrene by GPC of the polymer is usually 1. On the other hand, the upper limit of the ratio is usually 5, preferably 3 and more preferably 2.

In addition, Mw and Mn of the polymer in this specification are values measured using gel permeation chromatography (GPC) under the following conditions.
GPC column: 2 G2000HXL, 1 G3000HXL, 1 G4000HXL (above, Tosoh Corporation)
Column temperature: 40 ° C
Elution solvent: Tetrahydrofuran Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Detector: Differential refractometer Standard material: Monodisperse polystyrene

  [A] The polymer may contain a low molecular weight component having a molecular weight of 1,000 or less. [A] The upper limit of the content of the low molecular weight component in the polymer is preferably 1.0% by mass, more preferably 0.5% by mass, and still more preferably 0.3% by mass. As a minimum of the above-mentioned content, it is 0.01 mass%, for example. [A] By making content of the low molecular weight component of a polymer into the said range, the lithography performance of the said radiation sensitive composition can be improved more.

In addition, the content of the low molecular weight component of the polymer in the present specification is a value measured using high performance liquid chromatography (HPLC) under the following conditions.
Column: GL Science's “Inertsil ODA-25 μm column” (4.6 mmφ × 250 mm)
Eluent: Acrylonitrile / 0.1% by mass phosphoric acid aqueous solution Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Detector: Differential refractometer

[A] The lower limit of the fluorine atom content in the polymer is preferably 1% by mass, more preferably 2% by mass, further preferably 4% by mass, and particularly preferably 7% by mass. On the other hand, as an upper limit of the said content rate, 60 mass% is preferable, 40 mass% is more preferable, and 30 mass% is further more preferable. Here, the fluorine atom content (% by mass) of the polymer can be calculated from the structure of the polymer determined by ¹³ C-NMR spectrum measurement.

([A] Polymer Synthesis Method)
[A] The polymer can be produced, for example, by polymerizing a monomer corresponding to each predetermined structural unit in a suitable polymerization reaction solvent using a polymerization initiator such as a radical polymerization initiator. As a specific synthesis method, for example, a method of dropping a solution containing a monomer and a radical polymerization initiator into a polymerization reaction solvent or a solution containing a monomer to cause a polymerization reaction, a solution containing a monomer, , A method of dropping a solution containing a radical polymerization initiator separately into a polymerization reaction solvent or a solution containing a monomer to cause a polymerization reaction, a plurality of types of solutions containing each monomer, and initiation of radical polymerization Examples thereof include a method in which a solution containing an agent is dropped into a solution containing a polymerization reaction solvent or a monomer separately to cause a polymerization reaction.

  Examples of the radical polymerization initiator include azobisisobutyronitrile (AIBN), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2-cyclopropylpropylene). Pionitrile), azo radical initiators such as 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2′-azobisisobutyrate; benzoyl peroxide, t-butyl hydroperoxide, And peroxide radical initiators such as cumene hydroperoxide. Among these, as the radical polymerization initiator, AIBN and dimethyl 2,2'-azobisisobutyrate are preferable, and AIBN is more preferable. These radical initiators can be used alone or in combination of two or more.

  As a solvent used for the said polymerization, the thing similar to the solvent which the said radiation sensitive composition mentioned later contains can be used, for example.

  As a minimum of reaction temperature in the above-mentioned polymerization, 40 ° C is preferred and 50 ° C is more preferred. On the other hand, the upper limit of the reaction temperature is preferably 150 ° C, more preferably 120 ° C. The lower limit of the reaction time in the polymerization is preferably 1 hour. On the other hand, the upper limit of the reaction time is preferably 48 hours, more preferably 24 hours.

  [A] The polymer is preferably recovered by a reprecipitation method. That is, after completion of the reaction, the target polymer is recovered as a powder by introducing the reaction solution into a reprecipitation solvent. As the reprecipitation solvent, alcohols, alkanes and the like can be used singly or in combination of two or more. In addition to the reprecipitation method, the polymer can be recovered by removing low molecular components such as monomers and oligomers by a liquid separation operation, a column operation, an ultrafiltration operation, or the like.

[[B] Sensitizer precursor]
[B] A sensitizer precursor is a component that generates a sensitizer that absorbs radiation (I) having a wavelength of more than 250 nm by exposure (radiation irradiation). [B] The sensitizer precursor includes the following (a) (hereinafter also referred to as “(a) radiation-sensitive acid-sensitizer generator”) and component (b) (hereinafter referred to as “(b) radiation-sensitive”. At least one of "sensitizer generator".
(A) When the radiation (II) is irradiated and the radiation (I) is not irradiated, an acid and the sensitizer are generated, and the radiation (II) is not irradiated and only the radiation (I) is irradiated. A radiation-sensitive acid-sensitizer generator that does not substantially generate the acid and sensitizer (b) when the radiation (II) is irradiated and the radiation (I) is not emitted, the sensitizer is A radiation-sensitive sensitizer generator that is generated and does not substantially generate the sensitizer when irradiated with only the radiation (I) without irradiation with the radiation (II)

  [B] As the sensitizer precursor, those that increase the absorption (absorbance) of radiation (I) of the sensitizer generated by the action of the [C] metal-containing compound described later are preferable. The radiation-sensitive composition can further increase sensitivity by using such a [B] sensitizer precursor. As such [B] sensitizer precursor, for example, [B] sensitizer precursor and / or the generated sensitizer interact with the metal atom of [C] metal-containing compound, such as coordination. The thing which has a possible site | part etc. is mentioned.

  In this case, the [B] sensitizer precursor itself is preferably one that does not increase the absorption of radiation (I) due to the presence of the [C] metal-containing compound. By using such a [B] sensitizer precursor, the radiation-sensitive composition can increase the contrast between the exposed part and the non-exposed part, and as a result, forms a better pattern. Can do.

((A) Radiation sensitive acid-sensitizer generator)
(A) The radiation-sensitive acid-sensitizer generator generates an acid and the sensitizer when irradiated with radiation (II) having a wavelength of 250 nm or less and not irradiated with the radiation (I), and When the radiation (II) is not irradiated and only the first radiation is irradiated, the acid and the sensitizer are not substantially generated. Since the (a) radiation-sensitive acid-sensitizer generator has the above properties, generation of the acid and sensitizer due to radiation (I) irradiation in the batch exposure step can be suppressed. (A) The radiation-sensitive acid-sensitizer generator may be a component different from the polymer [A] (hereinafter referred to as “(a) radiation-sensitive acid-sensitizer generator” as appropriate). [A] A part of the polymer may be used.

  (A) Examples of the radiation-sensitive acid-sensitizer generator include onium salt compounds, diazomethane compounds, and sulfonimide compounds. Examples of the onium salt compound include a sulfonium salt compound, a tetrahydrothiophenium salt compound, and an iodonium salt compound. The sulfonium salt compound is composed of a sulfonium cation and an acid anion. The tetrahydrothiophenium salt compound is composed of a tetrahydrothiophenium cation and an acid anion. The iodonium salt compound is composed of an iodonium cation and an acid anion.

  As the sulfonium salt compound, compounds represented by the following formulas (I) to (III) are preferable.

In the above formulas (I) to (III), R ¹ , R ² , R ¹ ′, R ² ′, R ¹ ″, R ² ″, R ³ and R ⁴ are each independently a hydrogen atom; Phenyl group; naphthyl group; anthracenyl group; phenoxy group; naphthoxy group; anthracenoxy group; amino group; amide group; halogen atom; straight chain, branched chain having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms), or A cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group); a phenoxy group substituted by an alkoxy group having 1 to 5 carbon atoms, a hydroxy group, an amino group, an amide group, or an alkyl group having 1 to 5 carbon atoms; C1-C30 (preferably C1-C5) linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably alkyl group), C1-C5 alkoxy group, amino group Amide group, Or a phenyl group substituted with a hydroxy group; an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an amino group, an amide group, or a naphthoxy group substituted with a hydroxy group; An anthracenoxy group substituted with an alkoxy group, an alkyl group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxy group; an alkoxy group having 1 to 5 carbon atoms, a phenoxy group, a naphthoxy group, an anthracenoxy group, an amino group, A linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) substituted with an amide group or a hydroxy group; Or the carbonyl group which the C1-C12 alkyl group couple | bonded is shown. In the above formulas (I) to (III), the hydrogen atom of the hydroxy group is a phenyl group; a halogen atom; a linear, branched or cyclic saturated group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Or an unsaturated hydrocarbon group (preferably an alkyl group); or a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Group), an alkoxy group having 1 to 5 carbon atoms, or a phenyl group substituted with a hydroxy group. When the hydrogen atom of the hydroxy group is substituted, the sulfonium salt compound will contain a ketal compound group or an acetal compound group. In formulas (I) to (III), any two or more groups of R ¹ , R ² , R ¹ ′, R ² ′, R ¹ ″, R ² ″, R ³ , and R ⁴ are A single bond or a double bond, or —CH ₂ —, —O—, —S—, —SO ₂ —, —SO ₂ NH—, —C (═O) —, —C (═O) O— , —NHCO—, —NHC (═O) NH—, —CHR ^e —, —CR ^e ₂ —, —NH— or —NR ^e — to form a ring structure. May be. R ^e is a phenyl group; a phenoxy group; a halogen atom; a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). ); A phenoxy group substituted with an alkoxy group having 1 to 5 carbon atoms, a hydroxy group, or an alkyl group having 1 to 5 carbon atoms; or a straight chain having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms), A phenyl group substituted with a branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group), an alkoxy group having 1 to 5 carbon atoms, or a hydroxy group is shown. R ¹ , R ² , R ¹ ′, R ² ′, R ¹ ″, R ² ″, R ³ and R ⁴ are preferably each independently a phenyl group; a phenoxy group; A phenoxy group substituted with an alkyl group; or a phenyl group substituted with an alkoxy group having 1 to 5 carbon atoms or a hydroxy group. In the formulas (I) to (III), X ⁻ represents an anion of an acid, preferably a strong acid, more preferably a super strong acid.

In the above formulas (I) to (III), —C (—OH) R ¹ R ² , —C (—OH) R ¹ ′ R ² ′, and —C (—OH) R ¹ ″ R ² ″ Examples of the group represented by the above include groups represented by the following formulas. In addition, * in a formula shows the coupling | bond part with the sulfur ion in said formula (I)-(III). In the groups represented by —C (—OH) R ¹ R ² , —C (—OH) R ¹ ′ R ² ′, and —C (—OH) R ¹ ″ R ² ″, The carbon atom to which the hydroxy group is bonded becomes a carbonyl group by pattern exposure. Thus, in the compounds represented by the above formulas (I) to (III), —C (—OH) R ¹ R ² , —C (—OH) R ¹ 'R ² ', and —C (— OH) The group represented by R ¹ ″ R ² ″ is separated after pattern exposure to generate a sensitizer.

  As the iodonium salt compound, compounds represented by the following formulas (IV) to (V) are preferable.

In the above formulas (IV) to (V), R ⁵ , R ⁶ , R ⁵ ′, R ⁶ ′ and R ⁷ are each independently a hydrogen atom; a phenyl group; a naphthyl group; an anthracenyl group; a phenoxy group; Naphthoxy group; anthracenoxy group; amino group; amide group; halogen atom; linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) (preferably Alkyl group); a phenoxy group substituted with an alkoxy group having 1 to 5 carbon atoms, a hydroxy group, an amino group, an amide group, or an alkyl group having 1 to 5 carbon atoms; 1 to 30 carbon atoms (preferably 1 to 1 carbon atoms) 5) a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group), an alkoxy group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxy group. A phenyl group substituted with an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxy group; an alkoxy group having 1 to 5 carbon atoms and a carbon number An anthracenoxy group substituted with an alkyl group of 1 to 5, an amino group, an amide group, or a hydroxy group; an alkoxy group having 1 to 5 carbon atoms, a phenoxy group, a naphthoxy group, an anthracenoxy group, an amino group, an amide group, or a hydroxy group; A linear, branched, or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) substituted with 1 or 12; A carbonyl group to which an alkyl group is bonded is shown. In the above formulas (IV) to (V), the hydrogen atom of the hydroxy group is a phenyl group; a halogen atom; a linear, branched or cyclic saturated group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Or an unsaturated hydrocarbon group (preferably an alkyl group); or a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Group), an alkoxy group having 1 to 5 carbon atoms, or a phenyl group substituted with a hydroxy group. When the hydrogen atom of the hydroxy group is substituted, the iodonium salt compound will contain a ketal compound group or an acetal compound group. In formulas (IV) to (V), any two or more groups of R ⁵ , R ⁶ , R ⁵ ′, R ⁶ ′, and R ⁷ are each a single bond or a double bond, or —CH _{2 -, - O -, - S} -, - SO 2 NH -, - C (= O) -, - C (= O) O -, - NHCO -, - NHC (= O) NH -, - CHR f - , —CR ^f ₂ —, —NH—, or —NR ^f — may be used to form a ring structure. R ^f represents a phenyl group; a phenoxy group; a halogen atom; a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) (preferably an alkyl group). ); A phenoxy group substituted with an alkoxy group having 1 to 5 carbon atoms, a hydroxy group, or an alkyl group having 1 to 5 carbon atoms; or a straight chain having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms), A phenyl group substituted with a branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group), an alkoxy group having 1 to 5 carbon atoms, or a hydroxy group is shown. R ⁵ , R ⁶ , R ⁵ ′, R ⁶ ′ and R ⁷ are preferably each independently a phenyl group; a phenoxy group; an alkoxy group having 1 to 5 carbon atoms, a hydroxy group, or 1 to 5 carbon atoms. A phenoxy group substituted with an alkyl group, or a phenyl group substituted with an alkoxy group having 1 to 5 carbon atoms or a hydroxy group. In formulas (IV) to (V), Y ⁻ represents an anion of an acid, preferably a strong acid, more preferably a super strong acid.

In the above formulas (IV) to (V), examples of the groups represented by —C (—OH) R ⁵ R ⁶ and —C (—OH) R ⁵ 'R ⁶ ' include, for example, the above formulas (I) to ( A group represented by —C (—OH) R ¹ R ² , —C (—OH) R ¹ ′ R ² ′, —C (—OH) R ¹ ″ R ² ″ and the like exemplified in III) Similar groups are mentioned.

Y ^- The anion represented by the following general formula (XX), the anion of the acid is preferably represented by (XXI) and (XXII), more preferably anions of the acid represented by the following general formula (XX) .

In the general formulas (XX), (XXI), and (XXII), R ^{18 to} R ²¹ each independently represents an organic group. Examples of the organic group include an alkyl group, an aryl group, and a group in which a plurality of these groups are linked. The organic group is preferably an alkyl group substituted at the 1-position with a fluorine atom or a fluoroalkyl group, and a phenyl group substituted with a fluorine atom or a fluoroalkyl group. When the organic group has a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by exposure increases, and the sensitivity tends to be improved. However, the organic group preferably does not contain a fluorine atom as a substituent at the terminal.

The acid anion preferably has at least one anion group selected from the group consisting of a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methide anion. . Examples of the acid anion include, for example, the general formula “R ²² —SO ₃ ^— ” (R ²² is a linear, branched or cyclic alkyl group, halogenated alkyl group, aryl which may have a substituent. An anion represented by a group or an alkenyl group). The carbon number of the linear or branched alkyl group as R ²² is preferably 1 or more and 10 or less. For example, when R ²² is an alkyl group, examples of the acid anion include methane sulfonate, n-propane sulfonate, n-butane sulfonate, n-octane sulfonate, 1-adamantane sulfonate, 2-norbornane sulfonate, d-camphor-10- Examples thereof include alkyl sulfonates such as sulfonate. The halogenated alkyl group as R ²² is one in which part or all of the hydrogen atoms in the alkyl group are substituted with halogen atoms, and the alkyl group preferably has 1 to 10 carbon atoms. However, a linear or branched alkyl group is more preferable, and a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, tert-butyl group, tert-pentyl group, and isopentyl group are more preferable. And as a halogen atom by which a hydrogen atom is substituted, a fluorine atom, a chlorine atom, an iodine atom, a bromine atom etc. are mentioned, for example. In the halogenated alkyl group, it is preferable that 50% to 100% of the total number of hydrogen atoms in the alkyl group (alkyl group before halogenation) are substituted with halogen atoms, and all the hydrogen atoms are substituted with halogen atoms. More preferably. Here, the halogenated alkyl group is preferably a fluorinated alkyl group. The number of carbon atoms in the fluorinated alkyl group is preferably 1 or more and 10 or less, more preferably 1 or more and 8 or less, and most preferably 1 or more and 4 or less. Further, the fluorination rate of the fluorinated alkyl group is preferably 10% or more and 100% or less, more preferably 50% or more and 100% or less, and in particular, those in which all hydrogen atoms are substituted with fluorine atoms have an acid strength. Since it becomes strong, it is preferable. Examples of such a preferable fluorinated alkyl group include a trifluoromethyl group, a heptafluoro-n-propyl group, and a nonafluoro-n-butyl group.

R ²² may have a substituent. The said substituent contains the bivalent coupling group containing an oxygen atom. Examples of the linking group include an oxygen atom (ether bond: —O—), an ester bond (—C (═O) —O—), an amide bond (—C (═O) —NH—), and a carbonyl group (— Non-hydrocarbon oxygen-containing linking groups such as C (═O) —), sulfonyl groups (—SO ₂ —), carbonate bonds (—O—C (═O) —O—), and the like can be mentioned.

(A) As a radiation sensitive acid-sensitizer generator, what is represented by following formula (1) is preferable. That is, the anion of the acid represented by Y ⁻ preferably has a structure represented by the following formula (1).

In the above formula (1), R ^p1 is a monovalent group containing a ring structure having 6 or more ring members. R ^p2 is a divalent linking group. R ^p3 and R ^p4 are each independently a hydrogen atom, a fluorine atom, a monovalent hydrocarbon group having 1 to 20 carbon atoms or a monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms. R ^p5 and R ^p6 are each independently a fluorine atom or a monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms. n ^p1 is an integer of 0 to 10. n ^p2 is an integer of 0 to 10. n ^p3 is an integer of 1 to 10. When n ^p1 is 2 or more, the plurality of R ^p2 may be the same or different. When n ^p2 is 2 or more, the plurality of R ^p3 may be the same or different, and the plurality of R ^p4 may be the same or different. When n ^p3 is 2 or more, the plurality of R ^p5 may be the same or different, and the plurality of R ^p6 may be the same or different. X ⁺ is a monovalent radiation-sensitive onium cation.

  Here, the “number of ring members” refers to the number of atoms constituting a ring of an aromatic ring structure, aromatic heterocyclic structure, alicyclic structure and aliphatic heterocyclic structure, and in the case of a polycyclic ring structure, The number of atoms that make up the ring. The “hydrocarbon group” includes a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. The “hydrocarbon group” may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. The “chain hydrocarbon group” refers to a hydrocarbon group that does not include a cyclic structure but includes only a chain structure, and includes both a linear hydrocarbon group and a branched hydrocarbon group. The term “alicyclic hydrocarbon group” refers to a hydrocarbon group that includes only an alicyclic structure as a ring structure and does not include an aromatic ring structure, and includes a monocyclic alicyclic hydrocarbon group and a polycyclic alicyclic group. Includes both hydrocarbon groups. However, it is not necessary to be composed only of the alicyclic structure, and a part thereof may include a chain structure. “Aromatic hydrocarbon group” refers to a hydrocarbon group containing an aromatic ring structure as a ring structure. However, it is not necessary to be composed only of an aromatic ring structure, and a part thereof may include a chain structure or an alicyclic structure.

Examples of the monovalent group including a ring structure having 6 or more ring members represented by R ^p1 include a monovalent group including an alicyclic structure having 6 or more ring members and an aliphatic heterocyclic structure having 6 or more ring members. A monovalent group, a monovalent group containing an aromatic ring structure having 6 or more ring members, a monovalent group containing an aromatic heterocyclic structure having 6 or more ring members, and the like.

Examples of the alicyclic structure having 6 or more ring members include monocyclic cycloalkane structures such as a cyclohexane structure, a cycloheptane structure, a cyclooctane structure, a cyclononane structure, a cyclodecane structure, and a cyclododecane structure;
Monocyclic cycloalkene structures such as cyclohexene structure, cycloheptene structure, cyclooctene structure, cyclodecene structure;
Polycyclic cycloalkane structures such as norbornane structure, adamantane structure, tricyclodecane structure and tetracyclododecane structure;
Examples thereof include polycyclic cycloalkene structures such as a norbornene structure and a tricyclodecene structure.

Examples of the aliphatic heterocyclic structure having 6 or more ring members include lactone structures such as a hexanolactone structure and a norbornane lactone structure;
Sultone structures such as hexanosultone structure and norbornane sultone structure;
An oxygen atom-containing heterocyclic structure such as an oxacycloheptane structure or an oxanorbornane structure;
Nitrogen atom-containing heterocyclic structures such as azacyclohexane structure and diazabicyclooctane structure;
Examples thereof include a sulfur atom-containing heterocyclic structure having a thiacyclohexane structure and a thianorbornane structure.

Examples of the aromatic ring structure having 6 or more ring members include a benzene structure, a naphthalene structure, a phenanthrene structure, and an anthracene structure.

  Examples of the aromatic heterocyclic structure having 6 or more ring members include oxygen atom-containing heterocyclic structures such as furan structure, pyran structure and benzopyran structure, nitrogen atom-containing heterocyclic structures such as pyridine structure, pyrimidine structure and indole structure. Can be mentioned.

The lower limit of the number of ring members of the ring structure of R ^p1 is preferably 7, more preferably 8, more preferably 9, and particularly preferably 10. On the other hand, the upper limit of the number of ring members is preferably 15, more preferably 14, still more preferably 13, and particularly preferably 12. By setting the number of ring members in the above range, the acid diffusion length can be further appropriately shortened, and as a result, the LWR performance and the like in the radiation-sensitive composition of the present embodiment can be further improved. .

A part or all of the hydrogen atoms ^{contained in} the ring structure of R ^p1 may be substituted with a substituent. Examples of the substituent include halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom, hydroxy group, carboxy group, cyano group, nitro group, alkoxy group, alkoxycarbonyl group, alkoxycarbonyloxy group, acyl group, Examples include an acyloxy group. Of these, a hydroxy group is preferred.

Among these, R ^p1 is preferably a monovalent group containing an alicyclic structure having 6 or more ring members and a monovalent group containing an aliphatic heterocyclic structure having 6 or more ring members, and an alicyclic group having 9 or more ring members. A monovalent group containing a ring structure and a monovalent group containing an aliphatic heterocyclic structure having 9 or more ring members are more preferred. An oxo-4-oxatricyclo [4.3.1.1 ^3,8 ] undecan-yl group is more preferred, and an adamantyl group is particularly preferred.

Examples of the divalent linking group represented by R ^p2 include a carbonyl group, an ether group, a carbonyloxy group, a sulfide group, a thiocarbonyl group, a sulfonyl group, and a divalent hydrocarbon group. The divalent linking group represented by R ^p2 is preferably a carbonyloxy group, a sulfonyl group, an alkanediyl group and a cycloalkanediyl group, more preferably a carbonyloxy group and a cycloalkanediyl group, a carbonyloxy group and a norbornanediyl group. A group is more preferred, and a carbonyloxy group is particularly preferred.

Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms represented by R ^p3 and R ^p4 include an alkyl group having 1 to 20 carbon atoms. Examples of the monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms represented by R ^p3 and R ^p4 include a fluorinated alkyl group having 1 to 20 carbon atoms. R ^p3 and R ^p4 are preferably a hydrogen atom, a fluorine atom and a fluorinated alkyl group, more preferably a fluorine atom and a perfluoroalkyl group, and still more preferably a fluorine atom and a trifluoromethyl group.

Examples of the monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms represented by R ^p5 and R ^p6 include a fluorinated alkyl group having 1 to 20 carbon atoms. R ^p5 and R ^p6 are preferably a fluorine atom and a fluorinated alkyl group, more preferably a fluorine atom and a perfluoroalkyl group, still more preferably a fluorine atom and a trifluoromethyl group, and particularly preferably a fluorine atom.

The lower limit of n ^p1 is preferably 0. On the other hand, the upper limit of n ^p1 is preferably 5, more preferably 3, more preferably 2, and particularly preferably 1.

The lower limit of n ^p2 is preferably 0. On the other hand, the upper limit of n ^p2 is preferably 5, more preferably 2, and even more preferably 1.

The lower limit of n ^p3 is preferably 1. On the other hand, the upper limit of n ^p3 is preferably 5, more preferably 4, more preferably 3, and particularly preferably 2.

Y ^- as the anion of the acid represented by, for example, include anions represented by the following formula, but is not limited thereto.

  Moreover, as an anion as described in said formula (1), the following are mentioned, for example.

  When (a) the radiation-sensitive acid-sensitizer generator is a part of the [A] polymer, (a) the radiation-sensitive acid-sensitizer generator removes one hydrogen atom from the above compound. Groups are present in the form attached to the polymer.

  (A) When the radiation-sensitive acid-sensitizer generator is a component different from the [A] polymer, the (a) radiation-sensitive acid-sensitizer generator with respect to 100 parts by mass of the polymer [A] As a minimum of content, 0.005 mass part is preferred and 0.1 mass part is more preferred. On the other hand, as an upper limit of the said content, 50 mass parts is preferable and 30 mass parts is more preferable.

  (A) When the radiation-sensitive acid-sensitizer generator is a part of the [A] polymer, (a) the radiation-sensitive acid-sensitization with respect to 1 mol of all structural units constituting the [A] polymer. As a minimum of the content rate of the structural unit derived from a body generator, 0.001 mol is preferable, 0.002 mol is more preferable, and 0.01 mol is further more preferable. On the other hand, the upper limit of the content ratio is preferably 0.5 mol, more preferably 0.3 mol.

  If the content or content ratio is smaller than the lower limit, the sensitivity may decrease. On the other hand, when the content or content ratio exceeds the upper limit, it may be difficult to form a film or the rectangularity in the cross-sectional shape of the pattern may be reduced.

((B) Radiation-sensitive sensitizer generator)
(B) The radiation-sensitive sensitizer generator generates the sensitizer when irradiated with radiation (II) and does not emit radiation (I), and does not emit radiation (II). The above sensitizer is not substantially generated when only the light is irradiated. (B) The radiation sensitive sensitizer generator is different from the above (a) radiation sensitive acid-sensitizer generator. Even if the (b) radiation-sensitive sensitizer generator is a component different from the [A] polymer (hereinafter referred to as “(b) a radiation-sensitive sensitizer generator” as appropriate), the [A] It may be part of a polymer.

  In the radiation-sensitive composition, the chemical structure of (b) the radiation-sensitive sensitizer generator is converted by direct or indirect reaction upon irradiation with radiation (II), and acid generation occurs upon irradiation with radiation (I). Produce a sensitizer to assist. Since this sensitizer absorbs radiation (I) more easily than the (b) radiation-sensitive sensitizer generator, the exposed portion where the sensitizer is generated when pattern exposure is performed with the radiation (II). And the non-exposed portion of the pattern where the sensitizer is not generated differ greatly in the amount of absorption of radiation (I), and the contrast of the amount of absorption is easily obtained.

  (B) The radiation-sensitive sensitizer generating agent is preferably a carbonyl compound having a carbonyl group that absorbs radiation (I) when irradiated with radiation (II). Examples of the carbonyl compound include aldehyde, ketone, carboxylic acid, carboxylic acid ester and the like. The above reaction causes a shift in the peak of the absorption wavelength of radiation only in the (b) radiation-sensitive sensitizer generating agent in the pattern exposure portion. Therefore, if pattern exposure is performed with radiation having a wavelength that can be absorbed only by the pattern exposure portion after pattern exposure, only the pattern exposure portion can be selectively sensitized. (B) As the radiation-sensitive sensitizer generator, an alcohol compound represented by the following formula (VI) is more preferable, and a secondary alcohol compound may be used. In the present specification, the alcohol compound does not mean only a compound having an alcoholic hydroxyl group, but includes a ketal compound, an acetal compound, an orthoester compound, etc., in which a hydrogen atom of the alcoholic hydroxyl group is substituted. May be. (B) When the radiation-sensitive sensitizer generator is a ketal compound or an acetal compound, heating is performed after pattern exposure and before batch exposure in order to accelerate the hydrolysis reaction to the carbonyl compound by the acid catalyst generated by pattern exposure. May be.

式（ＶＩ）中、Ｒ^８、Ｒ^９及びＲ^１０は、それぞれ独立して、水素原子；フェニル基；ナフチル基；アントラセニル基；ピリジル基；炭素数１〜５のアルコキシ基；炭素数１〜５のアルキルチオ基；フェノキシ基；ナフトキシ基；アントラセノキシ基；アミノ基；アミド基；ハロゲン原子；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、アミノ基、アミド基、若しくはヒドロキシル基で置換された、炭素数１〜５のアルコキシ基；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、アミノ基、アミド基、若しくはヒドロキシル基で置換された、炭素数１〜５のアルキルチオ基；炭素数１〜５のアルコキシ基、ヒドロキシル基、アミノ基、アミド基、若しくは炭素数１〜５のアルキル基で置換されたフェノキシ基；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、アミノ基、アミド基、若しくはヒドロキシル基で置換されたフェニル基；炭素数１〜５のアルコキシ基、炭素数１〜５のアルキル基、アミノ基、アミド基、若しくはヒドロキシル基で置換されたナフトキシ基；炭素数１〜５のアルコキシ基、炭素数１〜５のアルキル基、アミノ基、アミド基、若しくはヒドロキシル基で置換されたアントラセノキシ基；炭素数１〜５のアルコキシ基、フェノキシ基、ナフトキシ基、アントラセノキシ基、アミノ基、アミド基、若しくはヒドロキシル基で置換された、炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；又は炭素数１〜１２のアルキル基が結合したカルボニル基を示す。アルコール化合物は、式（ＶＩ）中のアルコール性水酸基（ヒドロキシル基）がチオール基となったチオール化合物であってもよい。上記式（ＶＩ）中、ヒドロキシル基又はチオール基の水素原子は、フェニル基；ハロゲン原子；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；又は炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、若しくはヒドロキシル基で置換されたフェニル基で置換されていてもよい。式中、Ｒ^８、Ｒ^９及びＲ^１０のうち任意の２つ以上の基は、単結合若しくは二重結合により、又は−ＣＨ_２−、−Ｏ−、−Ｓ−、−ＳＯ_２−、−ＳＯ_２ＮＨ−、−Ｃ（＝Ｏ）−、−Ｃ（＝Ｏ）Ｏ−、−ＮＨＣＯ−、−ＮＨＣ（＝Ｏ）ＮＨ−、−ＣＨＲ^ｇ−、−ＣＲ^ｇ _２−、−ＮＨ−若しくは−ＮＲ^ｇ−を含む結合を介して環構造を形成してもよい。Ｒ^ｇは、フェニル基；フェノキシ基；ハロゲン原子；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；炭素数１〜５のアルコキシ基、ヒドロキシル基、若しくは炭素数１〜５のアルキル基で置換されたフェノキシ基；又は炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、若しくはヒドロキシル基で置換されたフェニル基を示す。Ｒ^８、Ｒ^９及びＲ^１０は、それぞれ独立して、好ましくは水素原子；フェニル基；フェノキシ基；炭素数１〜５のアルコキシ基、ヒドロキシル基、若しくは炭素数１〜５のアルキル基で置換されたフェノキシ基；又は炭素数１〜５のアルコキシ基、若しくはヒドロキシル基で置換されたフェニル基を示す。

In formula (VI), R ⁸ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom; a phenyl group; a naphthyl group; an anthracenyl group; a pyridyl group; an alkoxy group having 1 to 5 carbon atoms; An alkylthio group; a phenoxy group; a naphthoxy group; an anthracenoxy group; an amino group; an amide group; a halogen atom; a linear, branched, or cyclic saturated or unsaturated group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) A saturated hydrocarbon group (preferably an alkyl group); a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms), An alkoxy group having 1 to 5 carbon atoms substituted with an alkoxy group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxyl group; 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) A linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group), an alkoxy group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxyl group, An alkylthio group having 1 to 5 carbon atoms; a phenoxy group substituted with an alkoxy group having 1 to 5 carbon atoms, a hydroxyl group, an amino group, an amide group, or an alkyl group having 1 to 5 carbon atoms; 1 to 30 carbon atoms (preferably carbon Substituted with a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) of 1 to 5), an alkoxy group of 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxyl group A phenyl group substituted by an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxyl group; An anthracenoxy group substituted by an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxyl group; an alkoxy group having 1 to 5 carbon atoms, a phenoxy group, a naphthoxy group, and an anthracenoxy group A linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably 1 to 30 carbon atoms, preferably 1 to 5 carbon atoms) substituted with an amino group, an amide group or a hydroxyl group Alkyl group); or a carbonyl group to which an alkyl group having 1 to 12 carbon atoms is bonded. The alcohol compound may be a thiol compound in which the alcoholic hydroxyl group (hydroxyl group) in formula (VI) is a thiol group. In the formula (VI), the hydrogen atom of the hydroxyl group or thiol group is a phenyl group; a halogen atom; a linear, branched or cyclic saturated group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) or An unsaturated hydrocarbon group (preferably an alkyl group); or a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). ), An alkoxy group having 1 to 5 carbon atoms, or a phenyl group substituted with a hydroxyl group. In the formula, any two or more groups of R ⁸ , R ⁹ and R ¹⁰ are each a single bond or a double bond, or —CH ₂ —, —O—, —S—, —SO ₂ —, — SO ₂ NH—, —C (═O) —, —C (═O) O—, —NHCO—, —NHC (═O) NH—, —CHR ^g —, —CR ^g ₂ —, —NH— or A ring structure may be formed through a bond containing —NR ^g —. R ^g is a phenyl group; a phenoxy group; a halogen atom; a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). ); A phenoxy group substituted with an alkoxy group having 1 to 5 carbon atoms, a hydroxyl group, or an alkyl group having 1 to 5 carbon atoms; or a straight chain having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms), A phenyl group substituted with a branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group), an alkoxy group having 1 to 5 carbon atoms, or a hydroxyl group is shown. R ⁸ , R ⁹ and R ¹⁰ are preferably each independently substituted with a hydrogen atom; a phenyl group; a phenoxy group; an alkoxy group having 1 to 5 carbon atoms, a hydroxyl group, or an alkyl group having 1 to 5 carbon atoms. Or a phenyl group substituted with an alkoxy group having 1 to 5 carbon atoms or a hydroxyl group.

In addition, as a ketal compound or acetal compound in which the hydrogen atom of the hydroxyl group in formula (VI) is substituted, a compound represented by the following formula (XXXVI) is preferable. That is, (b) the radiation-sensitive sensitizer generating agent may be a compound represented by the following formula (XXXVI). When either one of R ^{9 and} R ¹⁰ is a hydrogen atom, it can be said that the compound represented by the following formula (XXXVI) is an acetal compound.

式（ＸＸＸＶＩ）中、Ｒ^９及びＲ^１０は上記式（ＶＩ）中のＲ^９及びＲ^１０とそれぞれ同義である。Ｒ^９及びＲ^１０は、上記式（ＶＩ）中のＲ^９及びＲ^１０と同様に環構造を形成していてもよい。式（ＸＸＸＶＩ）中、Ｒ^２３及びＲ^２４は、それぞれ独立して、フェニル基；ハロゲン原子；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；又は炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、若しくはヒドロキシル基で置換されたフェニル基を示す。Ｒ^２３及びＲ^２４は、単結合、二重結合、−ＣＨ_２−、−Ｏ−、−Ｓ−、−ＳＯ_２−、−ＳＯ_２ＮＨ−、−Ｃ（＝Ｏ）−、−Ｃ（＝Ｏ）Ｏ−、−ＮＨＣＯ−、ＮＨＣ（＝Ｏ）ＮＨ−、−ＣＨＲ^ｇ−、−ＣＲ^ｇ _２、−ＮＨ−又は−ＮＲ^ｇ−を含む結合を介して環構造を形成していてもよい。Ｒ^ｇは上記式（ＶＩ）中のＲ^ｇと同義である。ケタール化合物又はアセタール化合物は、式（ＸＸＸＶＩ）中のＲ^２３及び／又はＲ^２４と結合する酸素原子が硫黄に置き換えられたチオケタール化合物又はチオアセタール化合物であってもよい。

Wherein (XXXVI), ^{R 9} and ^{R 10} are the same meanings as ^{R 9} and ^{R 10} in formula (VI). R ⁹ and ^{R 10,} may form a similarly ring structure with ^{R 9} and ^{R 10} in formula (VI). In formula (XXXVI), R ²³ and R ²⁴ each independently represent a phenyl group; a halogen atom; a linear, branched or cyclic saturated group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Or an unsaturated hydrocarbon group (preferably an alkyl group); or a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Group), an alkoxy group having 1 to 5 carbon atoms, or a phenyl group substituted with a hydroxyl group. R ²³ and R ²⁴ are a single bond, a double bond, —CH ₂ —, —O—, —S—, —SO ₂ —, —SO ₂ NH—, —C (═O) —, —C (= A ring structure may be formed through a bond containing O) O—, —NHCO—, NHC (═O) NH—, —CHR ^g —, —CR ^g ₂ , —NH— or —NR ^g —. . R ^g has the same meaning as ^{R g} in the formula (VI). The ketal compound or acetal compound may be a thioketal compound or a thioacetal compound in which the oxygen atom bonded to R ²³ and / or R ²⁴ in formula (XXXVI) is replaced with sulfur.

A ketal compound and an acetal compound can be obtained by reacting a carbonyl compound with an alcohol. The above reaction can be referred to as a reaction for protecting a carbonyl group that contributes to radiosensitization, and R ²³ and R ²⁴ in the above formula (XXXVI) can be referred to as a protecting group for a carbonyl group. In this case, the reaction in which the radiation-sensitive sensitizer generating agent becomes a sensitizer by radiation or the like can be referred to as a deprotection reaction. Examples of the reactivity of the protecting group (ease of deprotection reaction) are shown below. The reactivity of the protecting group increases as it goes to the right and decreases as it goes to the left. For example, when a methoxy group is used as a protecting group for a carbonyl group, the reactivity of the deprotection reaction is high, and the deprotection reaction tends to proceed under an acid catalyst even at room temperature. As described above, the deprotection reaction proceeds at room temperature, so that there is an advantage that blurring of the image can be prevented. On the other hand, when a deprotection reaction occurs in a pattern unexposed portion at the time of pattern exposure and a sensitizer is generated, the contrast in the film may be deteriorated. In order to prevent the formation of a sensitizer in the pattern unexposed area, a protecting group can be selected so as to increase the activation energy of the deprotection reaction (decrease the reactivity of the protecting group). From the viewpoint of lowering the reactivity of the protecting group, a cyclic protecting group in which R ²³ and R ^{24 in} formula (XXXVI) are bonded to each other to form a ring structure is more preferable. Examples of the ring structure include a 6-membered ring and a 5-membered ring, and a 5-membered ring is preferable. When a protective group having low reactivity is used, the radiation-sensitive composition preferably contains a first scavenger described later, and it is desirable to bake the film after pattern exposure and before batch exposure. By performing baking, unnecessary acid in the unexposed portion of the pattern is neutralized by the capturing agent, and the contrast of the latent image can be improved. In addition, the baking can compensate for the decrease in the reactivity of the protecting group, and the roughness of the latent image of the acid in the film can be reduced by the diffusion of the substance by baking.

  The ketal type (b) radiation-sensitive sensitizer generating agent may be compounds represented by the following formulas (XXVII) to (XXX).

Wherein ^{(XXVII) ~ (XXXI),} R 23 and ^{R 24} are the same meanings as ^{R 23} and ^{R 24} in the formula (XXXVI). In formulas (XXVII) to (XXXI), the hydrogen atom of the aromatic ring may be substituted with an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms, and the aromatic ring is bonded to another aromatic ring Thus, a naphthalene ring or an anthracene ring may be formed. R ²⁵ represents an alkyl group having 1 to 5 carbon atoms. (B) When the compounds represented by the above formulas (XXVII) to (XXXI) are used as the radiation-sensitive sensitizer generating agent, (b) when the sensitizer is changed from the radiation-sensitive sensitizer generating agent. The shift of the absorption wavelength of radiation is larger, and a more selective sensitization reaction can be caused in the pattern exposure part. Moreover, the compound which has atoms, such as a nitrogen atom and a sulfur atom which can interact, such as coordination, to the metal atom of a [C] metal containing compound like the compound represented by (XXIX)-(XXXI) was used. In this case, (b) it is possible to further increase the shift in the absorption wavelength of the radiation and / or increase in the absorbance of the radiation when the sensitizer is changed from the radiation-sensitive sensitizer generating agent, and the radiation-sensitive composition. The sensitivity can be further increased.

  In addition, as an orthoester compound by which the hydrogen atom of the hydroxyl group in Formula (VI) was substituted, the compound represented by a following formula (XLVI) is preferable. That is, (b) the radiation-sensitive sensitizer generating agent may be a compound represented by the following formula (XLVI).

式（ＸＬＶＩ）中、Ｒ^９は上記式（ＶＩ）中のＲ^９と同義である。式（ＸＬＶＩ）中、Ｒ^３８〜Ｒ^４０は、それぞれ独立して、フェニル基；ハロゲン原子；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素（好ましくはアルキル基基）；又は炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、若しくはヒドロキシル基で置換されたフェニル基を示す。Ｒ^３８〜Ｒ^４０は、単結合若しくは二重結合により、又は−ＣＨ_２−、−Ｏ−、−Ｓ−、−ＳＯ_２−、−ＳＯ_２ＮＨ−、−Ｃ（＝Ｏ）−、−Ｃ（＝Ｏ）Ｏ−、−ＮＨＣＯ−、−ＮＨＣ（＝Ｏ）ＮＨ−、−ＣＨＲ^ｇ−、−ＣＲ^ｇ _２、−ＮＨ−若しくは−ＮＲ^ｇ−を含む結合を介して環構造を形成していてもよい。Ｒ^ｇは上記式（ＶＩ）中のＲ^ｇと同義である。

Wherein (XLVI), ^{R 9} has the same meaning as ^{R 9} in the formula (VI). In formula (XLVI), R ^{38 to} R ⁴⁰ each independently represent a phenyl group; a halogen atom; a linear, branched or cyclic saturated group having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Or an unsaturated hydrocarbon (preferably an alkyl group); or a linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms). Group), an alkoxy group having 1 to 5 carbon atoms, or a phenyl group substituted with a hydroxyl group. R ^{38 to} R ⁴⁰ are each a single bond or a double bond, or —CH ₂ —, —O—, —S—, —SO ₂ —, —SO ₂ NH—, —C (═O) —, —C A ring structure is formed through a bond containing (═O) O—, —NHCO—, —NHC (═O) NH—, —CHR ^g —, —CR ^g ₂ , —NH— or —NR ^g —. May be. R ^g has the same meaning as ^{R g} in the formula (VI).

  The ortho ester compound is decomposed by a deprotection reaction in pattern exposure to become, for example, a carboxylic acid ester or carboxylic acid containing a carbonyl group. As the ortho ester compound, the carboxyl group portion of the sensitizer having a carboxyl group is replaced with OBO (for example, 4-methyl 2,6,7-trioxabicyclo [2.2.2] octane-1-yl) ( An OBO ester compound represented by the following formula (XLVII) is preferred. The (b) radiation-sensitive sensitizer generator in which the carboxyl group is protected with OBO generates carboxylic acid by the acid catalyst generated during pattern exposure, shifts the radiation absorption wavelength, and acts as a sensitizer during batch exposure. . (B) By generating carboxylic acid from the radiation-sensitive sensitizer generating agent, the polarity of the film changes, for example, from nonpolar to polar in the pattern exposure part. For this reason, the ortho ester compound also functions as a dissolution accelerator in the development process, and contributes to an improvement in the contrast of the film. (B) When the radiation-sensitive sensitizer generating agent contains an OBO ester compound, it is possible to simultaneously generate a sensitizer and a polarity change reaction.

式（ＸＬＶＩＩ）中、Ｒ^４１及びＲ^４２は、それぞれ独立して、水素原子；フェニル基；ナフチル基；アントラセニル基；フェノキシ基；ナフトキシ基；アントラセノキシ基；アミノ基；アミド基；ハロゲン原子；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；炭素数１〜５のアルコキシ基、ヒドロキシル基、アミノ基、アミド基、若しくは炭素数１〜５のアルキル基で置換されたフェノキシ基；炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）、炭素数１〜５のアルコキシ基、アミノ基、アミド基、若しくはヒドロキシル基で置換されたフェニル基；炭素数１〜５のアルコキシ基、炭素数１〜５のアルキル基、若しくはヒドロキシル基で置換されたナフトキシ基；炭素数１〜５のアルコキシ基、炭素数１〜５のアルキル基、アミノ基、アミド基、若しくはヒドロキシル基で置換されたアントラセノキシ基；炭素数１〜５のアルコキシ基、フェノキシ基、ナフトキシ基、アントラセノキシ基、アミノ基、アミド基、若しくはヒドロキシル基で置換された、炭素数１〜３０（好ましくは炭素数１〜５）の直鎖状、分岐鎖状若しくは環状の飽和若しくは不飽和炭化水素基（好ましくはアルキル基）；又は炭素数１〜１２のアルキル基が結合したカルボニル基を示す。Ｒ^４１及びＲ^４２は、それぞれ独立して、好ましくは水素原子；フェニル基；フェノキシ基；炭素数１〜５のアルコキシ基、ヒドロキシル基、若しくは炭素数１〜５のアルキル基で置換されたフェノキシ基；又は炭素数１〜５のアルコキシ基、若しくはヒドロキシル基で置換されたフェニル基を示す。

In formula (XLVII), R ⁴¹ and R ⁴² each independently represent a hydrogen atom; a phenyl group; a naphthyl group; an anthracenyl group; a phenoxy group; a naphthoxy group; an anthracenoxy group; an amino group; 1 to 30 (preferably 1 to 5 carbon atoms) linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group); an alkoxy group having 1 to 5 carbon atoms, a hydroxyl group, amino Group, amide group, or phenoxy group substituted with an alkyl group having 1 to 5 carbon atoms; linear, branched or cyclic saturated or unsaturated having 1 to 30 carbon atoms (preferably 1 to 5 carbon atoms) A phenyl group substituted by a hydrocarbon group (preferably an alkyl group), an alkoxy group having 1 to 5 carbon atoms, an amino group, an amide group, or a hydroxyl group; carbon A naphthoxy group substituted by an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, or a hydroxyl group; an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an amino group, an amide group, Or an anthracenoxy group substituted with a hydroxyl group; an alkoxy group having 1 to 5 carbon atoms, a phenoxy group, a naphthoxy group, an anthracenoxy group, an amino group, an amide group, or a hydroxyl group, substituted with 1 to 30 carbon atoms (preferably A linear, branched or cyclic saturated or unsaturated hydrocarbon group (preferably an alkyl group) having 1 to 5 carbon atoms; or a carbonyl group to which an alkyl group having 1 to 12 carbon atoms is bonded. R ⁴¹ and R ⁴² are each independently preferably a hydrogen atom; a phenyl group; a phenoxy group; a phenoxy group substituted with an alkoxy group having 1 to 5 carbon atoms, a hydroxyl group, or an alkyl group having 1 to 5 carbon atoms. Or a phenyl group substituted with an alkoxy group having 1 to 5 carbon atoms or a hydroxyl group;

  (B) As a radiation sensitive sensitizer generating agent, the compound etc. which are represented by a following formula are mentioned, for example. These compounds are alcohol compounds in which the hydrogen atom of the alcoholic hydroxyl group is not substituted, and change into a ketone compound by a reaction during pattern exposure.

  The following compounds are examples of ketal compounds or acetal compounds in which the carbonyl group of the sensitizer is protected. These compounds become a sensitizer containing a ketone in a pattern exposure part by a catalytic action by an acid generated by pattern exposure.

  The following compounds are examples of orthoester compounds having carbon atoms substituted with three alkoxy groups.

  The ortho ester compound is deprotected by an acid catalyst generated during pattern exposure to produce an ester having a carbonyl group (methyl carboxylate in the following example).

  The following chemical formula is a derivative in which the carboxyl group part of a sensitizer having a carboxyl group is protected with OBO (for example, 4-methyl-2,6,7-trioxabicyclo [2.2.2] octane-1-yl). This is an example of an OBO ester compound.

  The OBO ester compound generates the following carboxylic acid by an acid catalyst generated during pattern exposure.

  Examples of sensitizers generated from the above-mentioned (a) radiation-sensitive acid-sensitizer generator and (b) radiation-sensitive sensitizer generator upon exposure include chalcone and its derivatives, 1,2-diketones and their Derivatives, benzoin and its derivatives, benzophenone and its derivatives, fluorene and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, xanthene and its derivatives, thioxanthene and its derivatives, xanthone and its derivatives, thioxanthone and its derivatives, cyanine and Its derivatives, merocyanine and its derivatives, naphthalocyanine and its derivatives, subphthalocyanine and its derivatives, pyrylium and its derivatives, thiopyrylium and its derivatives, tetraphylline and its derivatives, annulene and its derivatives, spiropyran and its derivatives Derivatives, spirooxazine and its derivatives, thiospiropyran and its derivatives, oxol and its derivatives, azine and its derivatives, thiazine and its derivatives, oxazine and its derivatives, indoline and its derivatives, azulene and its derivatives, azulene and its derivatives And derivatives thereof, porphyrin and derivatives thereof, porphyrazine and derivatives thereof, triarylmethane and derivatives thereof, phthalocyanine and derivatives thereof, acridone and derivatives thereof, coumarin and derivatives thereof, ketocoumarin and derivatives thereof, quinolinone and derivatives thereof, benzoxazole and Derivatives thereof, acridine and derivatives thereof, thiazine and derivatives thereof, benzothiazole and derivatives thereof, phenothiazine and derivatives thereof, benzotriazo Le and its derivatives, perylene and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, phenanthrene and derivatives thereof, pyrene and derivatives thereof, naphthacene and derivatives thereof, pentacene and its derivatives, and coronene and derivatives thereof. Moreover, it is preferable that the said sensitizer generate | occur | produced from said (b) radiation sensitizer generator by exposure contains a carbonyl compound. The carbonyl compound preferably contains ketone, aldehyde, carboxylic acid, ester, amide, enone, carboxylic acid chloride, carboxylic acid anhydride and the like as a carbonyl group. As the carbonyl compound, a compound that absorbs radiation on a long wavelength side exceeding 250 nm from the viewpoint of increasing the contrast of the radiation-sensitive composition by sufficiently separating the wavelength of radiation at the time of batch exposure from the wavelength of radiation at the time of pattern exposure. Is preferred. Examples of the carbonyl compound include benzophenone derivatives, xanthone derivatives, thioxanthone derivatives, coumarin derivatives, and acridone derivatives. The carbonyl compound may be a naphthalene derivative or an anthracene derivative, or an acridone derivative. In the sensitizer, the hydrogen of the aromatic ring is preferably substituted with an electron donating group. When the hydrogen in the aromatic ring of the sensitizer is replaced with an electron donating group, the electron transfer efficiency due to the sensitization reaction during batch exposure is improved, and the sensitivity of the radiation-sensitive composition tends to be improved. Further, (b) the difference between the radiation absorption wavelength of the radiation-sensitive sensitizer generating agent and the radiation absorption wavelength of the sensitizer can be increased, and the sensitizer can be selectively excited during batch exposure. Therefore, the contrast of the acid latent image in the radiation-sensitive composition tends to be improved. Examples of the electron donating group include a hydroxyl group, a methoxy group, an alkoxy group, an amino group, an alkylamino group, and an alkyl group.

  Examples of benzophenone and derivatives thereof include the following compounds.

  Examples of thioxanthone and derivatives thereof include the following compounds.

  Examples of xanthone and derivatives thereof include the following compounds.

  Examples of acridone and derivatives thereof include the following compounds.

  Examples of coumarin and its derivatives include the following compounds.

  The sensitizer may contain the following compound.

  Examples of the sensitizer include acetophenone, 2,2-dimethoxy-2-phenylacetophenone, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 1,2-hydroxy-2-methyl-1-phenylpropane-1 -One, α-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropanone, 2-hydroxy-2-methyl-1- (4-isopropylphenyl) propanone, 2-hydroxy-2- Methyl-1- (4-dodecylphenyl) propanone, 2-hydroxy-2-methyl-1-[(2-hydroxyethoxy) phenyl] propanone, benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 4-methoxybenzophenone, -Chlorobenzophenone, 4-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, 2-ethoxycarbonylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, benzophenone tetracarboxylic acid or its tetramethyl ester, 4,4 ' -Bis (dimethylamino) benzophenone, 4,4'-bis (dicyclohexylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, 4,4'-bis (dihydroxyethylamino) benzophenone, 4-methoxy-4 '-Dimethylaminobenzophenone, 4,4'-dimethoxybenzophenone, 4-dimethylaminobenzophenone, 4-dimethylaminoacetophenone, benzyl, anthraquinone, 2-t-butylanthra Quinone, 2-methylanthraquinone, phenanthraquinone, fluorenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone, 2- (dimethylamino) -2-[(4- Methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-hydroxy- 2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin phenyl ether, benzyldimethyl ketal, acridone, Chloroact Don, N-methylacridone, N-butylacridone, N-butyl-chloroacridone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyl Diphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, bis- (2, 6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl)- -Propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6-trimethylbenzoyl) phenylphosphine oxide (2,5,6-trimethylbenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1- Chloro-4-propoxythioxanthone, benzoyldi- (2,6-dimethylphenyl) phosphonate, 1- [4- (phenylthio) phenyl] -1,2-octanedione-2- (O-benzoyloxime), 1- [9 -Ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] ethanone-1- (O-acetyloxime), 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole -3-yl] -3-cyclopentylpropanone-1- (O-acetyloxime), 1- [4- (phenylthio) phenyl] -3-cyclopentylpropane-1,2-dione-2- (O-benzoyloxime) ), 2,2-dimethoxy-1,2-diphenylethane-1-one, 1- [4- (2-hydroxyethoxy) -phenyl]- -Hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propane- 1-one, phenylglyoxylic acid methyl ester, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpho Linophenyl) -butanone-1,1.2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone, 1- [9-ethyl-6- (2-methyl) Benzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) and the like.

  Examples of other sulfonium salt compounds include 4-cyclohexylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexylphenyldiphenylsulfonium perfluoro-n- Octanesulfonate, 4-cyclohexylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium trifluoromethanesulfonate 4-methanesulfonylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium perf Oro -n- octane sulfonate, 4-methanesulfonyl-phenyl diphenyl sulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethane ethanesulfonate.

  (B) When the radiation-sensitive sensitizer generator is a part of the [A] polymer, (b) the group obtained by removing one hydrogen atom from the above compound is a polymer. It exists in a form that binds to.

  When the (b) radiation-sensitive sensitizer generator is a component different from the [A] polymer, the lower limit of the content of the (b) radiation-sensitive sensitizer generator with respect to 100 parts by mass of the [A] polymer. Is preferably 0.005 parts by mass, more preferably 0.1 parts by mass. As an upper limit of the said content, 50 mass parts is preferable and 30 mass parts is more preferable.

  (B) When the radiation-sensitive sensitizer generator is a part of the [A] polymer, the (b) radiation-sensitive sensitizer generator with respect to 1 mol of all structural units constituting the [A] polymer As a minimum of the content rate of the derived structural unit, 0.001 mol is preferred, 0.002 mol is more preferred, and 0.01 mol is still more preferred. As an upper limit of the said content rate, 0.95 mol is preferable and 0.3 mol is more preferable.

  If the content or content ratio is smaller than the lower limit, the sensitivity may decrease. On the other hand, when the content or content ratio exceeds the upper limit, it may be difficult to form a film or the rectangularity in the cross-sectional shape of the pattern may be reduced.

  When the [B] sensitizer precursor is a component different from the [A] polymer, the lower limit of the content of the [B] sensitizer precursor relative to the total solid content of the radiation-sensitive composition is 0. 1 mass% is preferable, and 1 mass% is more preferable. On the other hand, the upper limit of the content is preferably 30% by mass, and more preferably 10% by mass. [B] By making content of a sensitizer precursor into the said range, the sensitivity of the said radiation sensitive composition can be improved more. Here, the “content of [B] sensitizer precursor” refers to the total content of components different from the [A] polymer in the [B] sensitizer precursor.

<[C] Metal-containing compound>
[C] The metal-containing compound is a compound containing a metal atom. [C] The metal-containing compound changes the absorption (absorption wavelength and absorbance) of the radiation (I) and the like by the sensitizer generated from the [B] sensitizer precursor, and preferably the radiation (I) irradiated by batch exposure Increase the absorbance by the sensitizer. As a result, the sensitivity of the radiation sensitive composition is further increased.

  [C] The metal atom of the metal-containing compound is preferably a metal atom having a large interaction with the sensitizer generated from the [B] sensitizer precursor, and more preferably a metal atom to which the sensitizer can coordinate.

  [C] Examples of the metal-containing compound include transition metal-containing compounds and typical metal-containing compounds.

Examples of the transition metal atom in the transition metal-containing compound include Group 3 metal atoms such as scandium, yttrium, lanthanum, and cerium;
Group 4 metal atoms such as titanium, zirconium and hafnium;
Group 5 metal atoms such as vanadium, niobium and tantalum;
Group 6 metal atoms such as chromium, molybdenum, tungsten;
Group 7 metal atoms such as manganese and rhenium;
Group 8 metal atoms such as iron, ruthenium, osmium;
Group 9 metal atoms such as cobalt, rhodium, iridium;
Group 10 metal atoms such as nickel, palladium, platinum;
Examples include Group 11 metal atoms such as copper, silver, and gold.

Examples of typical metal atoms in typical metal-containing compounds include Group 1 metal atoms such as lithium, sodium, potassium, rubidium, and cesium;
Group 2 metal atoms such as beryllium, magnesium, calcium, strontium, barium;
Group 12 metal atoms such as zinc, cadmium, mercury;
Group 13 metal atoms such as boron, aluminum, gallium, indium, thallium;
Group 14 metal atoms such as germanium, tin, lead;
Examples thereof include Group 15 metal atoms such as antimony and bismuth.

  Among these, it is considered that the interaction between the sensitizer generated from the [B] sensitizer precursor and the metal atom is large, and from the viewpoint of further improving the sensitivity of the radiation-sensitive composition, the transition metal-containing compound Group 8, Group 9, Group 10 and Group 11 metal atoms are more preferable, and copper, cobalt, ruthenium, palladium and platinum are particularly preferable.

  [C] Examples of the form of the metal-containing compound include a complex composed of a metal atom and a ligand, a salt composed of a metal cation and an anion, and an intermetallic compound.

  Examples of the ligand of the complex include a monodentate ligand and a polydentate ligand.

  Examples of the monodentate ligand include a hydroxo ligand (OH), a carboxy ligand (COOH), an amide ligand, an acyloxy ligand, and an amine ligand.

Examples of the amide ligand include an unsubstituted amide ligand (NH ₂ ), a methylamide ligand (NHMe), a dimethylamide ligand (NMe ₂ ), a diethylamide ligand (NEt ₂ ), and a dipropylamide ligand. Examples include a ligand (NPr ₂ ).

  Examples of the acyloxy ligand include formyloxy ligand, acetyloxy ligand, propionyloxy ligand, stearoyloxy ligand, acryloxy ligand and the like.

  Examples of the amine ligand include a pyridine ligand, a trimethylamine ligand, and a piperidine ligand.

  Examples of the polydentate ligand include hydroxy acid ester, β-diketone, β-keto ester, β-dicarboxylic acid ester, o-acylphenol, hydrocarbon having π bond, diphosphine, ammonia and the like.

  Examples of the hydroxy acid ester include glycolic acid ester, lactic acid ester, 2-hydroxycyclohexane-1-carboxylic acid ester, and salicylic acid ester.

  Examples of β-diketone include acetylacetone, 3-methyl-2,4-pentanedione, 3-ethyl-2,4-pentanedione, 2,2-dimethyl-3,5-hexanedione, and the like.

  Examples of the β-keto ester include acetoacetate ester, α-alkyl-substituted acetoacetate ester, β-ketopentanoic acid ester, benzoyl acetate ester, 1,3-acetone dicarboxylic acid ester, and the like.

  Examples of the β-dicarboxylic acid ester include malonic acid diester, α-alkyl substituted malonic acid diester, α-cycloalkyl substituted malonic acid diester, α-aryl substituted malonic acid diester, and the like.

  Examples of o-acylphenol include o-hydroxyacetophenone and o-hydroxybenzophenone.

Examples of hydrocarbons having a π bond include chain olefins such as ethylene and propylene;
Cyclic olefins such as cyclopentene, cyclohexene, norbornene;
Chain dienes such as butadiene and isoprene;
Cyclic dienes such as cyclopentadiene, methylcyclopentadiene, pentamethylcyclopentadiene, cyclohexadiene, norbornadiene;
Examples thereof include aromatic hydrocarbons such as benzene, toluene, xylene, hexamethylbenzene, naphthalene, and indene.

  Examples of the diphosphine include 1,1-bis (diphenylphosphino) methane, 1,2-bis (diphenylphosphino) ethane, 1,3-bis (diphenylphosphino) propane, and 2,2′-bis (diphenylphosphine). Fino) -1,1′-binaphthyl, 1,1′-bis (diphenylphosphino) ferrocene and the like.

  Examples of the complex include a compound represented by the following formula (C-1).

  In said formula (C-1), M is a metal atom. L is a ligand. x is an integer of 1-10. y is an integer of 1-20. When x is 2 or more, the plurality of M may be the same or different. When y is 2 or more, the plurality of L may be the same or different.

As x, 1-4 are preferable, 1 or 2 is more preferable, and 1 is further more preferable.
As y, 1-10 are preferable, 1-6 are more preferable, 1-4 are more preferable, and 1 or 2 is especially preferable.

  Examples of the metal cation of the salt include 1 to 6 valent cations of the metal atom. Among these,

Examples of the anion of the salt include sulfonate anions such as trifluoromethanesulfonate anion and p-toluenesulfonate anion;
Sulfate anion;
Phosphonate anions such as methanephosphonate anion and ethanephosphonate anion;
Carboxylate anions such as formate anion and acetate anion;
Nitrate anion;
Halide anions such as chloride anions, bromide anions, iodide anions;
And sulfonimide anions such as bis (methylsulfonyl) imide anion. Among these, a sulfonate anion is preferable, and a trifluoromethanesulfonate anion is more preferable.

  Examples of the salt include a compound represented by the following formula (C-2).

In the above formula (C-2), M ^{m +} is an m-valent metal cation. Z ⁿ⁻ is an n-valent anion. m is an integer of 1-6. n is an integer of 1 to 4. z is an integer of 1-10. w is an integer of 1-10. When z is 2 or more, the plurality of M ^{m +} may be the same or different. When w is 2 or more, the plurality of ^Zn- may be the same or different. However, it satisfies m × z = n × w.

As m, 1-4 are preferable, 1-3 are more preferable, and 1 or 2 is further more preferable.
n is preferably 1 or 2, and more preferably 1.

z is preferably 1 to 4, more preferably 1 or 2, and still more preferably 1.
As w, 1-4 are preferable, 1 or 2 is more preferable, and 1 is further more preferable.

  [C] As the metal-containing compound, [B] It is considered that the interaction between the sensitizer generated from the sensitizer precursor and the metal atom is large, and from the viewpoint of further improving the sensitivity of the radiation-sensitive composition, Complexes or salts are preferred, salts are more preferred, copper (II) salts are more preferred, and copper (II) trifluoromethanesulfonate is particularly preferred.

  [C] The lower limit of the content of the metal-containing compound is preferably 0.1 parts by weight, more preferably 1 part by weight, further preferably 3 parts by weight, with respect to 100 parts by weight of the polymer [A]. Part is particularly preferred. As an upper limit of the said content, 1,000 mass parts is preferable, 100 mass parts is more preferable, 50 mass parts is further more preferable, 20 mass parts is especially preferable.

  [C] The lower limit of the number of moles of metal atoms in the metal-containing compound is preferably 0.01 moles, more preferably 0.1 moles, and more preferably 0.3 moles per mole of [B] sensitizer precursor. Mole is more preferable, and 0.5 mol is particularly preferable. The upper limit of the number of moles is preferably 100 moles, more preferably 10 moles, further preferably 5 moles, and particularly preferably 2 moles.

  [C] The lower limit of the content of the metal-containing compound is preferably 1 part by weight, more preferably 10 parts by weight, still more preferably 30 parts by weight, with respect to 100 parts by weight of the [B] sensitizer precursor. Part by mass is particularly preferred. The upper limit of the content is preferably 10,000 parts by mass, more preferably 1,000 parts by mass, further preferably 500 parts by mass, and particularly preferably 200 parts by mass.

  [C] By making content of a metal containing compound into the said range, the sensitivity of the said radiation sensitive composition can further be improved.

[[D] solvent]
[D] The solvent is for dissolving each component of the radiation-sensitive composition and facilitating the formation of a film by a coating machine using a spin coating method or the like. In addition, the compound included in said (b) radiation sensitive sensitizer generator etc. shall be remove | excluded from [D] solvent. [D] Examples of the solvent include ketones such as cyclohexanone and methyl-2-amylketone; 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2- Alcohols such as propanol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether; and propylene glycol monomethyl ether acetate, propylene glycol monoethyl Ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, 3-ethoxypropiate Ethyl phosphate, acetate tert- butyl, tert- butyl propionate, propylene glycol monomethyl ether acetate, and esters such as propylene glycol monobutyl tert- butyl ether acetate.

[[E] Radiation sensitive acid generator]
[E] The radiation-sensitive acid generator is a component that generates an acid upon irradiation. The radiation-sensitive composition is not particularly necessary when an acid is generated by irradiation with radiation (II) in pattern exposure from the [B] sensitizer precursor and / or [C] metal-containing compound, but [A] When the [E] radiation sensitive acid generator is further contained in addition to the [D] component, the amount of acid generated in pattern exposure can be increased, and as a result, the sensitivity of the radiation sensitive composition is further increased. be able to. [E] The radiation-sensitive acid generator emits radiation (II) and does not emit radiation (I), generates acid, and does not emit radiation (II) but only radiation (I). In this case, it is preferable that the acid is not substantially generated. In this case, the [E] radiation-sensitive acid generator can generate an acid only at the pattern exposed portion of the film by a radiation sensitization reaction during batch exposure.

  [E] When acid is generated by irradiating the radiation-sensitive acid generator with radiation (I), the difference in acid concentration between the exposed and unexposed areas in pattern exposure can be patterned. The lower limit of the wavelength of radiation (I) that can reduce the amount of acid generated by irradiation with radiation (I) to such an extent that it can be maintained at a size of 300 nm is preferably 300 nm, more preferably 320 nm, and even more preferably 350 nm. [E] A pattern exposure unit irradiated with radiation (II) by setting the wavelength of radiation (I) to be not less than the above lower limit when the radiation-sensitive acid generator generates an acid upon irradiation with radiation (I). Then, due to the sensitizing action of the generated sensitizer, acid is generated when irradiated with radiation (I), and conversely, generation of acid during irradiation with radiation (I) is suppressed in a pattern unexposed portion where radiation (II) is not irradiated. The As a result, the sensitivity and contrast between the pattern exposed portion and the pattern unexposed portion can be improved.

  [E] The radiation-sensitive acid generator may be a component different from the [A] polymer (hereinafter referred to as “[E] radiation-sensitive acid generator” as appropriate). It may be a part. In this case, the [E] radiation sensitive acid generator is present in a form in which a group obtained by removing one hydrogen atom from the compound of the [E] radiation sensitive acid generator is bonded to the [A] polymer.

  [E] The radiation-sensitive acid generator is preferably a salt of a cation and an anion. Examples of the anion include the same anions as those exemplified as the acid anion in the above-mentioned (a) radiation-sensitive acid-sensitizer generating agent. Moreover, it is preferable that [E] a radiation sensitive acid generator is what is represented by the said Formula (1) similarly to the said (a) radiation sensitive acid-sensitizer generator. That is, as the anion in the [E] radiation sensitive acid generator, those described in the above formula (1) are preferable.

Examples of the monovalent onium cation represented by X ⁺ include a cation represented by the following formula (X-1) (hereinafter also referred to as “cation (X-1)”), and the following formula (X-2). And a cation represented by the following formula (X-3) (hereinafter also referred to as “cation (X-3)”), and the like. .

In the above formula (X-1), R ^a1 , R ^a2 and R ^a3 are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, substituted or unsubstituted. aromatic hydrocarbon group having 6 to 12 carbon atoms, a or a -OSO ₂ -R ^P or _-SO 2 -R ^Q, or two or more are combined with each other configured ring of these groups . R ^P and R ^Q are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, or a 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. k1, k2 and k3 are each independently an integer of 0 to 5. R ^a1 to R ^a3 and when ^{R P} and ^{R Q} are a plurality each of the plurality of ^R a1 ^{to R a3} and ^{R P} and ^{R Q} may be the same as or different from each other.

In the above formula (X-2), R ^b1 represents a substituted or unsubstituted linear or branched alkyl group having 1 to 8 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon having 6 to 8 carbon atoms. It is a group. k4 is an integer of 0-7. If R ^b1 is plural, the plurality of R ^b1 may be the same or different, and plural R ^b1 may represent a constructed ring aligned with each other.
R ^b2 is a substituted or unsubstituted linear or branched alkyl group having 1 to 7 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 or 7 carbon atoms. k5 is an integer of 0-6. If R ^b2 is plural, the plurality of R ^b2 may be the same or different, and plural R ^b2 may represent a keyed configured ring structure. r is an integer of 0-3. R ^b3 is a single bond or a divalent organic group having 1 to 20 carbon atoms. t is an integer of 0-2.

In the above formula (X-3), R ^c1 and R ^c2 each independently represent a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted carbon number of 6 12 aromatic hydrocarbon group, or an -OSO ₂ -R ^R or _-SO 2 -R ^S, or two or more are combined with each other configured ring of these groups. R ^R and R ^S are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, or a 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. k6 and k7 are each independently an integer of 0 to 5. R ^{c1, R} c2, ^R when ^R and ^{R S} is plural respective plurality of ^{R c1,} R c2, ^{R R} and ^{R S} may have respectively the same or different.

Examples of the unsubstituted linear alkyl group represented by R ^{a1 to} R ^a3 , R ^b1 , R ^b2 , R ^c1 and R ^c2 include a methyl group, an ethyl group, an n-propyl group, and an n-butyl group. Is mentioned.

Examples of the unsubstituted branched alkyl group represented by R ^{a1 to} R ^a3 , R ^b1 , R ^b2 , R ^c1 and R ^c2 include i-propyl group, i-butyl group, sec-butyl group, t- A butyl group etc. are mentioned.

Examples of the unsubstituted aromatic hydrocarbon group represented by R ^{a1 to} R ^a3 , R ^c1 and R ^c2 include aryl groups such as phenyl group, tolyl group, xylyl group, mesityl group and naphthyl group; benzyl group and phenethyl group And an aralkyl group such as a group.

Examples of the unsubstituted aromatic hydrocarbon group represented by R ^b1 and R ^b2 include a phenyl group, a tolyl group, and a benzyl group.

Examples of the divalent organic group represented by R ^b3 include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, and a divalent aromatic hydrocarbon group.

Examples of the divalent chain hydrocarbon group include alkanediyl groups such as methanediyl group, ethanediyl group, propanediyl group, butanediyl group;
Alkenediyl groups such as ethenediyl group, propenediyl group, butenediyl group;
Examples include alkynediyl groups such as ethynediyl group, propynediyl group, and butynediyl group.

Examples of the divalent alicyclic hydrocarbon group include monocyclic cycloalkanediyl groups such as a cyclopropanediyl group, a cyclobutanediyl group, a cyclopentanediyl group, and a cyclohexanediyl group;
Monocyclic cycloalkenediyl groups such as cyclopropenediyl group and cyclobutenediyl group;
A polycyclic cycloalkanediyl group such as a norbornanediyl group, an adamantanediyl group, a tricyclodecanediyl group, a tetracyclododecanediyl group;
Examples thereof include polycyclic cycloalkenediyl groups such as norbornenediyl group and tricyclodecenediyl group.

Examples of the divalent aromatic hydrocarbon group include arenediyl groups such as benzenediyl group, toluenediyl group, xylenediyl group, naphthalenediyl group;
Examples thereof include arenediyl (cyclo) alkanediyl groups such as benzenediylmethanediyl group and naphthalenediylcyclohexanediyl group.

  The hetero atom-containing group refers to a group having a divalent or higher valent hetero atom in the structure. The hetero atom-containing group may have one hetero atom or two or more hetero atoms.

  The divalent or higher valent hetero atom of the hetero atom-containing group is not particularly limited as long as it is a hetero atom having a valence of 2 or higher. For example, an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom And boron atoms.

As the hetero atom-containing group, for example _{-SO -, - SO 2 -,} - SO 2 O -, - SO 3 - groups consist of a hetero atom such as;
-CO-, -COO-, -COS-, -CONH-, -OCOO-, -OCOS-, -OCONH-, -SCONH-, -SCSNH-, -SCSS-, etc. Group and the like.

  Examples of the substituent that may be substituted for the hydrogen atom of the alkyl group and aromatic hydrocarbon group and the substituent that the organic group may have include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples include a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, an alkoxy group, an alkoxycarbonyl group, an alkoxycarbonyloxy group, an acyl group, and an acyloxy group. Among these, a halogen atom is preferable and a fluorine atom is more preferable.

R ^{a1 to} R ^a3 , R ^b1 , R ^b2 , R ^c1 and R ^c2 include an unsubstituted linear or branched alkyl group, a fluorinated alkyl group, an unsubstituted monovalent aromatic hydrocarbon group, —OSO ₂ —R ″ and —SO ₂ —R ″ are preferred, —SO ₂ —R ″, fluorinated alkyl groups, unsubstituted linear or branched alkyl groups, and unsubstituted monovalent aromatics. A hydrocarbon group is more preferable, and —SO ₂ —R ″ and an unsubstituted linear or branched alkyl group are further preferable. R ″ is an unsubstituted monovalent chain hydrocarbon group, an unsubstituted monovalent alicyclic hydrocarbon group or an unsubstituted monovalent aromatic hydrocarbon group.

  As k1, k2, and k3 in Formula (X-1), integers of 0 to 2 are preferable, 0 and 1 are more preferable, and 0 is more preferable. As k4 in Formula (X-2), an integer of 0 to 2 is preferable, 0 and 1 are more preferable, and 1 is more preferable. k5 is preferably an integer of 0 to 2, more preferably 0 and 1, and still more preferably 0. As r, 2 and 3 are preferable, and 2 is more preferable. As t, 0 and 1 are preferable, and 0 is more preferable. As k6 and k7 in Formula (X-3), an integer of 0 to 2 is preferable, 0 and 1 are more preferable, and 0 is more preferable.

Among these, as C ⁺ , cation (X-1) and cation (X-3) are preferable, and triphenylsulfonium cation, 4-methanesulfonylphenyldiphenylsulfonium cation, and bis (4-tert-butylphenyl). An iodonium cation is more preferred.

  Examples of such [E] radiation-sensitive acid generators include onium salt compounds, diazomethane compounds, N-sulfonyloxyimide compounds, and the like. Examples of the onium salt compound include a sulfonium salt compound, a tetrahydrothiophenium salt compound, and an iodonium salt compound. [E] As the radiation-sensitive acid generator, sulfonium salt compounds, iodonium salt compounds, sulfonyldiazomethane, N-sulfonyloxyimide compounds and oxime-O-sulfonate type radiation-sensitive acid generators are preferable, and sulfonium salt compounds and iodonium. A salt compound is more preferable.

  Examples of the sulfonium salt compounds include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, triphenylsulfonium 2-bicyclo [2.2.1] hept. 2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexane Xylphenyldiphenylsulfonium perfluoro-n-octanesulfonate, 4-cyclohexylphenyldiphenylsulfonium 2-bicyclo [2.2.1] To-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-methanesulfonylphenyl Examples include diphenylsulfonium perfluoro-n-octane sulfonate, 4-methanesulfonylphenyl diphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethane sulfonate, and the like. .

  Examples of the tetrahydrothiophenium salt compound include 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium. Nonafluoro-n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothio Phenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium Trifluoromethanesulfonate, 1- (6-n-butoxynaphthalene) 2-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (6-n- Butoxynaphthalen-2-yl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (3,5-dimethyl- 4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (3,5-dimethyl-4- Hydroxyphenyl) tetrahydrothiophenium perfluoro-n-oct Sulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate Etc.

  Examples of the iodonium salt compound include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium 2-bicyclo [2.2.1] hept-2- Yl-1,1,2,2-tetrafluoroethanesulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4 -T-butylphenyl) iodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2- Tiger fluoro ethanesulfonate.

  Examples of the N-sulfonyloxyimide compound include N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (nonafluoro-n-butanesulfonyl). Oxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept-5 En-2,3-dicarboximide, N- (2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) bicyclo [2.2. 1] hept-5-ene-2,3-dicarboximide and the like.

  Examples of the diazomethane compound include bis (n-propylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, bis (n-butylsulfonyl) diazomethane, bis (tert-butylsulfonium) diazomethane, bis (cyclopentylsulfonyl) diazomethane, and bis (cyclo Hexylsulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (4-chlorophenylsulfonyl) diazomethane, bis (p-tolylsulfonyl) diazomethane, bis (2,4-xylylsulfonyl) diazomethane, bis (4-isopropylphenylsulfonyl) ) Diazomethane, bis (4-tert-butylphenylsulfonyl) diazomethane, bis (naphthylsulfonyl) diazomethane, bis (anthracenylsulfur) ) Diazomethane.

  When the [E] radiation sensitive acid generator is a component different from the [A] polymer, the lower limit of the content of the [E] radiation sensitive acid generator relative to 100 parts by mass of the [A] polymer is 0. 1 part by mass is preferable, and 1 part by mass is more preferable. As an upper limit of the said content, 50 mass parts is preferable and 30 mass parts is more preferable.

  [E] When the radiation-sensitive acid generator is a part of the polymer constituting the [A] polymer, (1) the content ratio of (c) the radiation-sensitive acid generator to 1 mol of the polymer component As a minimum, 0.01 mol is preferred, 0.02 mol is more preferred, and 0.1 mol is still more preferred. On the other hand, the upper limit of the content ratio is preferably 0.5 mol, more preferably 0.3 mol.

  If the content or content ratio is smaller than the lower limit, the sensitivity may decrease. On the other hand, when the content or content ratio exceeds the upper limit, it may be difficult to form a film or the rectangularity in the cross-sectional shape of the pattern may be reduced.

[Acid diffusion control agent]
The radiation sensitive composition may contain an acid diffusion control agent. The acid diffusion control agent captures an acid and a cation and functions as a quencher. The radiation-sensitive composition contains an acid diffusion control agent to neutralize excess acid generated in the film, thereby increasing the chemical contrast of the latent image of the acid between the pattern exposed portion and the pattern non-exposed portion. Can be raised.

  The acid diffusion controller is classified into a compound having radiation sensitivity and a compound having no radiation sensitivity.

  As the compound having no radiation sensitivity, a basic compound is preferable. Examples of the basic compound include a hydroxide compound, a carboxylate compound, an amine compound, an imine compound, an amide compound, and more specifically, primary to tertiary aliphatic amines, aromatic amines, Heterocyclic amine, nitrogen-containing compound having carboxyl group, nitrogen-containing compound having sulfonyl group, nitrogen-containing compound having hydroxyl group, nitrogen-containing compound having hydroxyphenyl group, alcoholic nitrogen-containing compound, nitrogen-containing compound having carbamate group , Amide compounds, imide compounds, and the like. Among these, nitrogen-containing compounds having a carbamate group are preferred.

  The basic compounds include: Troger's base; hindered amines such as diazabicycloundecene (DBU) and diazabicyclononene (DBM); tetrabutylammonium hydroxide (TBAH) and tetrabutylammonium lactate It may be an ionic quencher.

  Examples of the primary aliphatic amine include ammonia, methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, pentylamine, tert-amylamine, and cyclopentylamine. Hexylamine, cyclohexylamine, heptylamine, octylamine, nonylamine, decylamine, dodecylamine, cetylamine, methylenediamine, ethylenediamine, tetraethylenepentamine and the like.

  Examples of the secondary aliphatic amine include dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, diisobutylamine, di-sec-butylamine, dipentylamine, dicyclopentylamine, and diheptyl. Xylamine, dicyclohexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, didodecylamine, dicetylamine, N, N-dimethylmethylenediamine, N, N-dimethylethylenediamine, N, N-dimethyltetraethylenepentamine, etc. It is done.

  Examples of the tertiary aliphatic amine include trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, triisobutylamine, tri-sec-butylamine, tripentylamine, tricyclopentylamine, Trihexylamine, tricyclohexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, tridodecylamine, tricetylamine, N, N, N ′, N′-tetramethylmethylenediamine, N, N , N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethyltetraethylenepentamine and the like.

  Examples of the aromatic amine and heterocyclic amine include aniline, N-methylaniline, N-ethylaniline, N-propylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, and 4-methylaniline. , Ethylaniline, propylaniline, trimethylaniline, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline, 2,6-dinitroaniline, 3,5-dinitroaniline, N, N- Aniline derivatives such as dimethyltoluidine; diphenyl (p-tolyl) amine; methyldiphenylamine; triphenylamine; phenylenediamine; naphthylamine; diaminonaphthalene; pyrrole, 2H-pyrrole, 1-methylpyrrole, 2,4-dimethylpyrrole, 2, 5-dimethylpi And pyrrole derivatives such as N-methylpyrrole; oxazole derivatives such as oxazole and isoxazole; thiazole derivatives such as thiazole and isothiazole; imidazole derivatives such as imidazole, 4-methylimidazole and 4-methyl-2-phenylimidazole; Pyrazole derivatives; furazane derivatives; pyrroline derivatives such as pyrroline and 2-methyl-1-pyrroline; pyrrolidine derivatives such as pyrrolidine, N-methylpyrrolidine, pyrrolidinone and N-methylpyrrolidone; imidazoline derivatives; imidazolidine derivatives; pyridine, methylpyridine, Ethylpyridine, propylpyridine, butylpyridine, 4- (1-butylpentyl) pyridine, dimethylpyridine, trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl- -Phenylpyridine, 4-tert-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 4-pyrrolidinopyridine, 2- (1-ethylpropyl) pyridine, aminopyridine, dimethylaminopyridine, etc. Pyridine derivatives; pyrimidine derivatives; pyrazoline derivatives; pyrazolidine derivatives; piperidine derivatives; piperazine derivatives; morpholine derivatives; indole derivatives; isoindole derivatives; 1H-indazole derivatives; indoline derivatives; quinoline, 3-quinolinecarbonitrile, etc. Quinoline derivatives; isoquinoline derivatives; cinnoline derivatives; quinazoline derivatives; quinoxaline derivatives; phthalazine derivatives; purine derivatives; Conductors; carbazole derivatives; phenanthridine derivatives; acridine derivatives; phenazine derivatives; 1,10-phenanthroline derivatives; adenine derivatives; adenosine derivatives; guanine derivatives;

  Examples of the nitrogen-containing compound having a carboxy group include aminobenzoic acid; indolecarboxylic acid; nicotinic acid, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, glycylleucine, leucine, methionine, phenylalanine, threonine, Examples include amino acid derivatives such as lysine, 3-aminopyrazine-2-carboxylic acid, and methoxyalanine.

  Examples of the nitrogen-containing compound having a sulfonyl group include 3-pyridinesulfonic acid and pyridinium p-toluenesulfonate.

  Examples of the nitrogen-containing compound having a hydroxyl group, the nitrogen-containing compound having a hydroxyphenyl group, and the alcoholic nitrogen-containing compound include 2-hydroxypyridine, aminocresol, 2,4-quinolinediol, 3-indolemethanol hydrate, Monoethanolamine, diethanolamine, triethanolamine, N-ethyldiethanolamine, N, N-diethylethanolamine, triisopropanolamine, 2,2′-iminodiethanol, 2-aminoethanol, 3-amino-1-propanol, 4- Amino-1-butanol, 4- (2-hydroxyethyl) morpholine, 2- (2-hydroxyethyl) pyridine, 1- (2-hydroxyethyl) piperazine, 1- [2- (2-hydroxyethoxy) ethyl] piperazi Piperidine ethanol, 1- (2-hydroxyethyl) pyrrolidine, 1- (2-hydroxyethyl) -2-pyrrolidinone, 3-piperidino-1,2-propanediol, 3-pyrrolidino-1,2-propanediol, 8 -Hydroxyurolidine, 3-cuincridinol, 3-tropanol, 1-methyl-2-pyrrolidineethanol, 1-aziridineethanol, N- (2-hydroxyethyl) phthalimide, N- (2-hydroxyethyl) isonicotine Examples include amides.

  Examples of the nitrogen-containing compound having a carbamate group include N- (tert-butoxycarbonyl) -L-alanine, N- (tert-butoxycarbonyl) -L-alanine methyl ester, (S)-(−)-2- ( tert-butoxycarbonylamino) -3-cyclohexyl-1-propanol, (R)-(+)-2- (tert-butoxycarbonylamino) -3-methyl-1-butanol, (R)-(+) -2- (tert-butoxycarbonylamino) -3-phenylpropanol, (S)-(−)-2- (tert-butoxycarbonylamino) -3-phenylpropanol, (R)-(+)-2- ( tert-butoxycarbonylamino) -3-phenyl-1-propanol, (S)-(−)-2- (tert-butoxycarbonyl) Amino) -3-phenyl-1-propanol, (R)-(+)-2- (tert-butoxycarbonylamino) -1-propanol, (S)-(−)-2- (tert-butoxycarbonylamino) -1-propanol, N- (tert-butoxycarbonyl) -L-aspartic acid 4-benzyl ester, N- (tert-butoxycarbonyl) -O-benzyl-L-threonine, (R)-(+)-1 -(Tert-Butoxycarbonyl) -2-tert-butyl-3-methyl-4-imidazolidinone, (S)-(-)-1- (tert-butoxycarbonyl) -2-tert-butyl-3-methyl -4-imidazolidinone, N- (tert-butoxycarbonyl) -3-cyclohexyl-L-alanine methyl ester, N- (ter -Butoxycarbonyl) -L-cysteine methyl ester, N- (tert-butoxycarbonyl) ethanolamine, N- (tert-butoxycarbonylethylenediamine), N- (tert-butoxycarbonyl) -D-glucosamine, Nα- (tert- Butoxycarbonyl) -L-glutamine, 1- (tert-butoxycarbonyl) imidazole, N- (tert-butoxycarbonyl) -L-isoleucine, N- (tert-butoxycarbonyl) -L-isoleucine methyl ester, N- (tert -Butoxycarbonyl) -L-leucinol, Nα- (tert-butoxycarbonyl) -L-lysine, N- (tert-butoxycarbonyl) -L-methionine, N- (tert-butoxycarbonyl) -3- (2-naphtho) ) -L-alanine, N- (tert-butoxycarbonyl) -L-phenylalanine, N- (tert-butoxycarbonyl) -L-phenylalanine methyl ester, N- (tert-butoxycarbonyl) -D-prolinal, N- (Tert-butoxycarbonyl) -L-proline, N- (tert-butoxycarbonyl) -L-proline-N′-methoxy-N′-methylamide, N- (tert-butoxycarbonyl) -1H-pyrazole-1-carboxyl Amidin, (S)-(−)-1- (tert-butoxycarbonyl) -2-pyrrolidinemethanol, (R)-(+)-1- (tert-butoxycarbonyl) -2-pyrrolidinemethanol, 1- ( tert-butoxycarbonyl) 3- [4- (1-pyrrolyl) phenyl] -L- Alanine, N- (tert-butoxycarbonyl) -L-serine, N- (tert-butoxycarbonyl) -L-serine methyl ester, N- (tert-butoxycarbonyl) -L-threonine, N- (tert-butoxycarbonyl) ) -P-toluenesulfonamide, N- (tert-butoxycarbonyl) -S-trityl-L-cysteine, Nα- (tert-butoxycarbonyl) -L-tryptophan, N- (tert-butoxycarbonyl) -L-tyrosine N- (tert-butoxycarbonyl) -L-tyrosine methyl ester, N- (tert-butoxycarbonyl) -L-valine, N- (tert-butoxycarbonyl) -L-valine methyl ester, N- (tert-butoxy Carbonyl) -L-valinol, tert Butyl N- (3-hydroxypropyl) carbamate, tert-butyl N- (6-aminohexyl) carbamate, tert-butylcarbamate, tert-butylcarbazate, tert-butyl-N- (benzyloxy) carbamate, tert- Butyl-4-benzyl-1-piperazinecarboxylate, tert-butyl (1S, 4S)-(−)-2,5-diazabicyclo [2.2.1] heptane-2-carboxylate, tert-butyl-N -(2,3-dihydroxypropyl) carbamate, tert-butyl (S)-(-)-4-formyl-2,2-dimethyl-3-oxazolidinecarboxylate, tert-butyl [R- (R *, S * ]]-N- [2-Hydroxy-2- (3-hydroxyphenyl) -1-methylethyl L] carbamate, tert-butyl-4-oxo-1-piperidinecarboxylate, tert-butyl-1-pyrrolecarboxylate, tert-butyl-1-pyrrolidinecarboxylate, tert-butyl (tetrahydro-2-oxo-3- Furanyl) carbamate and the like.

  Examples of the amide compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, 1-cyclohexylpyrrolidone and the like.

  Examples of the imide compound include phthalimide, succinimide, maleimide and the like.

  The compound having radiation sensitivity is classified into a compound that is decomposed by radiation and loses acid diffusion control ability (radiolysis type compound) and a compound that is generated by radiation and obtains acid diffusion control ability (radiation generation compound).

  The radiation-decomposable compound is decomposed only in the pattern exposure part in the pattern exposure step, so that the action of capturing the acid and cation is reduced in the pattern exposure part, and the action of capturing the acid and cation is maintained in the pattern non-exposed part. The For this reason, the chemical contrast of the latent image of the acid between the exposed part and the non-exposed part can be improved.

  As the radiolytic compound, sulfonate and carboxylate are preferable. The sulfonic acid in the sulfonate is preferably a weak acid, more preferably a hydrocarbon group having 1 to 10 carbon atoms, and the hydrocarbon group not containing fluorine. Examples of such sulfonic acid include sulfonic acids such as alkyl sulfonic acid, benzene sulfonic acid, and 10-camphor sulfonic acid. The carboxylic acid in the carboxylate is preferably a weak acid, more preferably a carboxylic acid having 1 to 20 carbon atoms. Examples of such carboxylic acids include carboxylic acids such as formic acid, acetic acid, propionic acid, tartaric acid, succinic acid, cyclohexyl carboxylic acid, benzoic acid, and salicylic acid. The radiolytic cation in the carboxylate of the radiolytic cation is preferably an onium cation, and examples of the onium cation include an iodonium cation.

  Since the radiation generating compound is generated only in the pattern exposure part in the pattern exposure step, an action of capturing an acid and a cation occurs in the pattern exposure part and does not occur in the pattern non-exposure part.

  The radiation generating compound may be generated in the batch exposure process without being generated in the pattern exposure process. In this case, the sensitizer can be efficiently generated in the exposed portion of the pattern exposure step, and unnecessary acids and cations in the non-exposed portion of the batch exposure step can be captured.

  As the radiation-generating compound, a compound that generates a base upon exposure (a radiation-sensitive base generator) is preferable, and a nitrogen-containing organic compound that generates an amino group is more preferable.

  Examples of the radiation sensitive base generator include, for example, JP-A-4-151156, JP-A-4-162040, JP-A-5-197148, JP-A-5-5995, JP-A-6-194634, JP-A-8-146608, and JP-A-10. -83079, and the compound as described in European Patent 622682.

  Examples of the radiation sensitive base generator include a compound containing a carbamate group (urethane bond), a compound containing an acyloxyimino group, an ionic compound (anion-cation complex), a compound containing a carbamoyloxyimino group, and the like. And a compound containing a carbamate group (urethane bond), a compound containing an acyloxyimino group, and an ionic compound (anion-cation complex) are preferable.

  Furthermore, as the radiation sensitive base generator, a compound having a ring structure in the molecule is preferable. Examples of this ring structure include benzene, naphthalene, anthracene, xanthone, thioxanthone, anthraquinone, fluorene, and the like.

  Examples of the radiation sensitive base generator include 2-nitrobenzyl carbamate, 2,5-dinitrobenzyl cyclohexyl carbamate, N-cyclohexyl-4-methylphenylsulfonamide, 1,1-dimethyl-2-phenylethyl. -N-isopropyl carbamate and the like.

  The acid diffusion control agent may be a compound (heat generation compound) that is generated by a thermal reaction and obtains acid diffusion control ability. In this case, it is desirable to generate in the baking process after the batch exposure process. Thus, it is preferable that the heating temperature in the baking process mentioned later is higher than the heating temperature in another process from a viewpoint that an acid diffusion control agent acquires acid diffusion control ability in a baking process.

  When the said radiation sensitive composition contains the said acid diffusion control agent, as a minimum of content of the acid diffusion control agent with respect to 100 mass parts of [A] polymers, 0.001 mass part is preferable, 0.01 mass Part is more preferred. On the other hand, as an upper limit of the said content, 20 mass parts is preferable and 10 mass parts is more preferable. When the said content is smaller than the said minimum, there exists a possibility that the said acid diffusion control agent cannot fully capture | acquire an acid and a cation. On the contrary, when the content exceeds the upper limit, the sensitivity may be excessively lowered.

[Radical scavenger]
The radical scavenger traps free radicals. When the radiation-sensitive composition contains the radical scavenger, generation of a sensitizer via a reaction due to radicals in the pattern non-exposed portion is reduced, and a pattern exposed portion and a non-exposed portion after a collective exposure step described later are performed. The contrast of the acid concentration with can be further improved. Examples of the radical scavenger include compounds such as phenolic compounds, quinone compounds, and amine compounds, and natural antioxidants such as rubber.

[Crosslinking agent]
The cross-linking agent is used to cause a cross-linking reaction between polymer components by an acid catalyst reaction in a baking step after collective exposure, to increase the molecular weight of the polymer component, and to insolubilize in the developer. 1) It is different from the polymer component. When the radiation-sensitive composition contains a crosslinking agent, the polar part becomes nonpolar at the same time as crosslinking and becomes insoluble in the developer, so that a negative resist material can be provided.

  The crosslinking agent is a compound having two or more functional groups. The functional group is preferably at least one selected from the group consisting of a (meth) acryloyl group, a hydroxymethyl group, an alkoxymethyl group, an epoxy group, and a vinyl ether group.

[Other polymers]
The radiation-sensitive composition may contain a polymer other than the [A] polymer. The other polymer is not particularly limited as long as it does not have the structural unit (I) in the [A] polymer, but may have the structural unit (II) in the [A] polymer, the structural unit (III), You may have structural unit (IV) and another structural unit.

  When the radiation-sensitive composition contains another polymer and the other polymer has the structural unit (II), the lower limit of the structural unit (II) with respect to all the structural units constituting the other polymer is 3 Mol% is preferable, 5 mol% is more preferable, and 10 mol% is further more preferable. As an upper limit of the said content rate, 40 mol% is preferable, 35 mol% is more preferable, and 30 mol% is further more preferable. By making the said content rate into the said range, the sensitivity in case EUV etc. are used as pattern exposure light can be improved more. On the other hand, when the said content rate exceeds the said upper limit, there exists a possibility that the rectangularity in the cross-sectional shape of a pattern may fall.

  When the radiation-sensitive composition contains another polymer and the other polymer has the structural unit (III), the lower limit of the content ratio of the structural unit (III) with respect to all the structural units constituting the other polymer Is preferably 1 mol%, more preferably 30 mol%, still more preferably 50 mol%. As an upper limit of the said content rate, 90 mol% is preferable, 80 mol% is more preferable, and 75 mol% is further more preferable. By making the content rate of structural unit (III) into the said range, the sensitivity of the said radiation sensitive composition can be improved more.

  When the said radiation sensitive composition contains another polymer and another polymer has structural unit (IV), as a minimum of the content rate of structural unit (IV) with respect to all the structural units which comprise other polymer. Is preferably 1 mol%, more preferably 10 mol%, further preferably 20 mol%, particularly preferably 25 mol%. As an upper limit of the said content rate, 70 mol% is preferable, 65 mol% is more preferable, 60 mol% is further more preferable, 55 mol% is especially preferable. By making the said content rate into the said range, the adhesiveness of the film | membrane formed from the said radiation sensitive composition and a board | substrate can be improved more.

  The radiation-sensitive composition contains another polymer, and the upper limit of the content ratio of the other structural units with respect to all the structural units constituting the other polymer is preferably 20 mol%, more preferably 10 mol%. .

  As an upper limit of content of the low molecular weight component in another polymer, 1.0 mass% is preferable, 0.5 mass% is more preferable, and 0.3 mass% is further more preferable. As a minimum of the above-mentioned content, it is 0.01 mass%, for example. By making content of the low molecular weight component of another polymer into the said range, the lithography performance of the said radiation sensitive composition can be improved more.

  Although the polystyrene conversion weight average molecular weight (Mw) by gel permeation chromatography (GPC) of other polymers is not particularly limited, the lower limit thereof is preferably 1,000, more preferably 2,000, and 2,500. More preferably, 3,000 is particularly preferable. The upper limit of Mw of other polymers is preferably 50,000, more preferably 30,000, still more preferably 20,000, and particularly preferably 15,000. By making Mw of another polymer into the said range, the applicability | paintability and development defect inhibitory property of the said radiation sensitive composition improve. When Mw of other polymers is smaller than the above lower limit, a film having sufficient heat resistance may not be obtained. Conversely, if the Mw of the other polymer exceeds the above upper limit, the developability of the film may be reduced.

  As a minimum of ratio (Mw / Mn) of Mw with respect to polystyrene conversion number average molecular weight (Mn) by GPC of other polymers, 1 is preferred. As an upper limit of the ratio, 5 is preferable, 3 is more preferable, and 2 is more preferable.

  The radiation-sensitive composition may have two or more polymers having different fluorine atom contents. Examples of such two or more polymers include [A] polymers and other polymers, and those having a higher fluorine atom content in other polymers than [A] polymers, [A] polymers And [A] a polymer having a higher fluorine atom content than other polymers, a polymer containing two or more [A] polymers having different fluorine atom contents, and fluorine atom content And those containing two or more other polymers having different from each other. As described above, the radiation-sensitive composition has two or more polymers having different fluorine atom contents, so that a polymer having a high fluorine atom content is unevenly distributed in the surface layer of the film, and the water-repellent polymer additive Can function as. As a result, elution of [B] sensitizer precursor, [E] radiation-sensitive acid generator, etc. from the film can be suppressed, and the dynamic contact angle on the film surface is improved and excellent water drainage characteristics are exhibited. Can be made. This enables high-speed scan exposure when performing immersion exposure described later.

[Other additives]
Examples of other additives include surfactants, antioxidants, dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, and dyes. Known materials can be selected for the surfactant, antioxidant, dissolution inhibitor, plasticizer, stabilizer, colorant, antihalation agent, and dye. As the surfactant, for example, an ionic or nonionic fluorine-based surfactant, a silicon-based surfactant, or the like can be used. Examples of the antioxidant include a phenolic antioxidant, an antioxidant made of an organic acid derivative, a sulfur-containing antioxidant, a phosphorus antioxidant, an amine antioxidant, and an antioxidant made of an amine-aldehyde condensate. And an antioxidant comprising an amine-ketone condensate.

[Method for preparing radiation-sensitive composition]
In the radiation-sensitive composition, for example, a [A] polymer, a [B] sensitizer precursor, a [C] metal-containing component, a [D] solvent, and an optional component as necessary are mixed at a predetermined ratio. Can be prepared. The radiation-sensitive composition is preferably filtered through a filter having a pore size of about 0.2 μm after mixing. The lower limit of the total solid content concentration of the radiation-sensitive composition is usually 0.1% by mass, preferably 0.5% by mass, and more preferably 1% by mass. On the other hand, the upper limit of the total solid content is usually 50% by mass, preferably 30% by mass, and more preferably 20% by mass.

<Pattern formation method>
The radiation sensitive composition is suitably used in a two-step exposure lithography process. That is, the lithography process (pattern formation method) according to this embodiment forms a film (hereinafter also referred to as “film (I)”) using the radiation-sensitive composition on one surface of the substrate. A step, a pattern exposure step of irradiating the film (I) with radiation having a wavelength of 250 nm or less, and a radiation having a wavelength of more than 250 nm on the film (I) after the pattern exposure step. A batch exposure step; a baking step for heating the film (I) after the batch exposure step; and a development step for bringing the film (I) after the baking step into contact with a developer.

  FIG. 1 is a process diagram showing a lithography process according to this embodiment. FIG. 2 is a process diagram showing an example of a pattern forming method using a conventional chemically amplified resist material.

As shown in FIG. 1, the lithography process according to this embodiment includes the following steps.
Step S1: Step of preparing a substrate to be processed Step S2: Step of forming a lower layer film and a film (I) (film forming step)
Step S3: A step of generating an acid in the exposed portion by pattern exposure (pattern exposure step)
Step S4: a step of multiplying acid only in the pattern exposure portion by batch exposure (collective exposure step)
Step S5: A step of causing a polarity change reaction by an acid catalyst in the pattern exposed portion by baking after exposure (baking step).
Step S6: a step of forming a pattern by development processing (development step)
Step S7: Step of transferring pattern by etching (etching step)

(Process S1)
The substrate to be processed (substrate to be processed) in the following steps may be composed of a semiconductor wafer such as a silicon substrate, a silicon dioxide substrate, a glass substrate, and an ITO substrate, and is insulated on the semiconductor wafer. A film layer may be formed.

(Process S2: Film formation process)
The film (I) is formed using the radiation-sensitive composition of this embodiment. Examples of the method for forming the film (I) include a method of applying a liquid radiation-sensitive composition by spin coating or the like, and a method of attaching a film-like (solid) radiation-sensitive composition. When applying a liquid radiation sensitive composition, you may volatilize the solvent in a radiation sensitive composition by heating (prebaking) after application | coating. The conditions for forming the film (I) are appropriately selected according to the properties of the radiation-sensitive composition, the thickness of the film (I) to be obtained, and the like. The average thickness of the film (I) is preferably from 1 nm to 5,000 nm, more preferably from 10 nm to 1,000 nm, and even more preferably from 30 nm to 200 nm.

  Prior to forming the film (I) on the substrate, a lower layer film (an antireflection film, a film for improving adhesion, a film for improving pattern shape, etc.) may be formed on the substrate. By forming the antireflection film, it is possible to suppress the occurrence of standing waves due to radiation reflected by the substrate or the like in the pattern exposure step. By forming a film for improving the adhesion of the film (I), the adhesion between the substrate and the film (I) can be improved. By forming a film for improving the pattern shape, the shape of the film (I) after development can be further improved. That is, it is possible to reduce the soaking shape or the constriction shape of the film (I). On the other hand, in order to prevent deterioration of the pattern shape due to the generation of standing waves of batch exposure radiation, it is desirable to design the thickness of the lower layer film so that reflection of radiation of batch exposure is also suppressed. The lower layer film is desirably a film that does not absorb the radiation for batch exposure. If the lower layer film absorbs the radiation of the batch exposure, a radiation sensitization reaction occurs in the film due to energy transfer or electron transfer from the lower layer film, and there is a possibility that acid is generated in the pattern unexposed part. For this reason, a buffer layer that does not propagate the radiation sensitization reaction may be disposed between the film (I) and the lower layer film to prevent sensitization from the lower layer film that has absorbed the radiation.

  A protective film may be further formed on the film (I). By forming the protective film, it is possible to suppress the deactivation of the sensitizer, acid, and these reaction intermediates generated in the pattern exposure step S3 and improve the process stability. In order to prevent the acid generation reaction in the unexposed area in the batch exposure process, the protective film is a non-absorbable material directly absorbed by the (a) radiation-sensitive acid-sensitizer generator or [E] radiation-sensitive acid generator. It may be an absorption film that absorbs at least a part of the wavelength of ionizing radiation. Use of the absorbing film suppresses the entry of out-of-band light (OOB light), which is ultraviolet radiation generated during EUV exposure, into the film (I), and the radiation-sensitive acid generator in the pattern unexposed area Alternatively, decomposition of the radiation-sensitive acid generating group can be prevented. Furthermore, when the absorption film is directly formed on the film (I), the radiation (I) in the batch exposure process is performed in order to suppress acid generation in the film (I) due to the radiation sensitization reaction in the pattern unexposed portion. It is preferable that it does not induce a radiosensitization reaction from the protective film. In addition, a buffer layer is disposed between the film (I) and the protective film so that the sensitizer in the film (I) is not sensitized by energy transfer or electron transfer from the protective film, and absorption by absorbing radiation. Sensitization from the film may be prevented. By forming the absorption film on the film (I) after the pattern exposure step S3 and before the batch exposure step S4, the film (I) after the pattern exposure step S3 is irradiated by radiation (I) in the batch exposure step S4. Direct generation of acid from the above-mentioned radiation-sensitive acid generator or radiation-sensitive acid-generating group remaining in the water can be further suppressed.

(Process S3: Pattern exposure process)
In the pattern exposure step S3, a light shielding mask having a predetermined pattern is arranged on the film (I) formed in the film formation step S2. Thereafter, the film (I) is irradiated (pattern exposure) with radiation (II) through the mask from an exposure apparatus (radiation irradiation module) having a projection lens, an electron optical system mirror, or a reflection mirror.

  The radiation (II) used for pattern exposure is radiation having a wavelength of 250 nm or less. The upper limit of the wavelength of the radiation is 250 nm, preferably 200 nm. On the other hand, the lower limit of the wavelength of the radiation is preferably 150 nm, and more preferably 190 nm.

  The radiation (II) may be ionizing radiation or non-ionizing radiation. Ionizing radiation is radiation that has sufficient energy to ionize atoms or molecules. In contrast, non-ionizing radiation is radiation that does not have sufficient energy to ionize atoms or molecules. Examples of the ionizing radiation include gamma rays, X-rays, alpha rays, heavy particle rays, proton rays, beta rays, ion beams, electron beams, EUV, and the like. The ionizing radiation used for pattern exposure is preferably an electron beam, EUV or ion beam, more preferably an electron beam or EUV. Examples of non-ionizing radiation include KrF excimer laser light and ArF excimer laser light.

  As a light source for pattern exposure, for example, an electron beam of 1 keV to 200 keV, EUV having a wavelength of 13.5 nm, excimer laser light of 193 nm (ArF excimer laser light), excimer laser light of 248 nm (KrF excimer laser light) is used. There are many cases. The exposure amount in pattern exposure may be smaller than that in the case of batch exposure using the radiation-sensitive composition of the present embodiment. The pattern exposure exposes the [B] sensitizer precursor in the film (I) to generate a sensitizer that absorbs radiation (I) having a wavelength of more than 250 nm.

  For exposure, a step-and-scan type exposure apparatus called a “scanner” is widely used. In this method, a pattern for each shot is formed by performing scanning exposure while synchronizing the mask and the substrate. By this exposure, a selective reaction occurs at the exposed portion in the film (I).

  Prior to performing the following batch exposure step S4, the (a) radiation-sensitive acid-sensitizer generator or [E] radiation-sensitive property is formed on the film (I) in the post-pattern exposure step S3. You may form the absorption film which absorbs at least one part of the wavelength of the radiation which an acid generator absorbs directly. (A) The radiation-sensitive acid-sensitizer generator remaining on the film (I) after the pattern exposure step S3 by irradiation with radiation (II) in the following batch exposure step S4 by forming an absorption film. Alternatively, [E] direct acid generation from the radiation-sensitive acid generator can be further suppressed.

  When the (b) radiation-sensitive sensitizer generator having an alcoholic hydroxyl group in which hydrogen atoms are not substituted is used, the film (I) is subjected to the following batch exposure step S4 after the pattern exposure step S3. Is preferably placed in a reduced-pressure atmosphere or an inert atmosphere containing nitrogen or argon. By placing the film (I) under the above-mentioned atmosphere, exposure of the film (I) during exposure to oxygen and the termination of radical reaction by this oxygen can be suppressed, and an acid by a trace amount of basic compound can be suppressed. Therefore, the process can be more stabilized. The upper limit of the time (storage time) until the collective exposure step S4 is performed after the pattern exposure step S3 is preferably 30 minutes, and more preferably 10 minutes. There exists a tendency which can suppress the fall of a sensitivity because storage time is 30 minutes or less. On the other hand, when (b) a radiation-sensitive sensitizer generating agent (that is, a ketal compound, an acetal compound or an orthoester compound) having an alcoholic hydroxyl group substituted with a hydrogen atom is used, after the pattern exposure step S3, the following Until the collective exposure step S4 is performed, it is preferable that the atmosphere in which the film (I) exists is in the atmosphere cleaned with an amine removal filter. When the above-mentioned (b) radiation-sensitive sensitizer generating agent is used, it may be treated in the atmosphere cleaned with an amine removing filter because it is not easily affected by oxygen as described above. By placing the membrane (I) in the above atmosphere, it is possible to suppress acid quenching by a small amount of a basic compound, so that the process tends to be further stabilized. The upper limit of the time (storage time) until the collective exposure step S4 is performed after the pattern exposure step S3 is preferably 30 minutes, and more preferably 10 minutes. There exists a tendency which can suppress the fall of a sensitivity because storage time is 30 minutes or less.

  In the pattern forming method of the present embodiment, after the pattern exposure step S3 and before the following batch exposure step S4, the step of transporting the substrate from the exposure apparatus that performs the pattern exposure step S3 to the exposure device that performs the batch exposure step S4 May be further provided. Further, the batch exposure may be performed in a coating and developing apparatus connected inline or in a module corresponding to an interface with the exposure machine. When the [B] sensitizer precursor contains a ketal compound, an acetal compound or an orthoester compound, the pattern forming method of the present embodiment is a baking step after the pattern exposure step S3 and before the following batch exposure step S4. S3a (also referred to as post pattern exposure bake (PPEB or PEB)) may be provided (see FIG. 3). The heating temperature in the baking step is preferably 30 ° C. or higher and 150 ° C. or lower, more preferably 50 ° C. or higher and 120 ° C. or lower, and further preferably 60 ° C. or higher and 100 ° C. or lower. The heating time is preferably 5 seconds to 3 minutes, more preferably 10 seconds to 60 seconds. Moreover, it is preferable to perform the said baking in the environment which controlled humidity. This is because when the hydrolysis reaction is used as a deprotection reaction for generating a sensitizer, the humidity affects the reaction rate. When the pattern forming method includes the baking step S3a, it is possible to accelerate the generation of a sensitizer by a hydrolysis reaction from an acetal compound, an ortho ester compound, a ketal compound, or the like to a carbonyl compound.

(Process S4: Batch exposure process)
In the collective exposure step S4, a high-sensitivity module (exposure device) having a projection lens (or light source) on the entire surface of the film (I) after the pattern exposure step S3 (the entire surface including the pattern exposed portion and the pattern unexposed portion). Or radiation (I) may be irradiated (collective exposure) from a radiation irradiation module. As this collective exposure, the entire wafer surface may be exposed at one time, a combination of local exposures, or overlapping exposure. As a light source for batch exposure, a general light source can be used. In addition to ultraviolet rays from mercury lamps and xenon lamps controlled to a desired wavelength by passing through a pan-pass filter or a cut-off filter, LEDs are used. Narrow-band ultraviolet light from a light source, laser diode, laser light source, or the like may be used. In the batch exposure, only the sensitizer generated at the pattern exposure portion in the film (I) absorbs radiation. For this reason, in the batch exposure, radiation is selectively absorbed in the pattern exposure portion. Therefore, during the batch exposure, the acid can be continuously generated only in the pattern exposure part, and the sensitivity can be greatly improved. On the other hand, since no acid is generated in the unexposed pattern portion, the sensitivity can be improved while maintaining the chemical contrast in the film (I).

  Moreover, since the radiation sensitive composition of this embodiment is used, the absorption of the radiation (I) in the sensitizer which generate | occur | produced in the pattern exposure part increases. Therefore, during the batch exposure, a larger amount of acid can be generated in the pattern exposure part, and the sensitivity can be further improved greatly.

  The radiation (I) used for batch exposure has a wavelength longer than the wavelength of the radiation (II), has a wavelength exceeding 250 nm, and is preferably near-ultraviolet (wavelength 250 to 450 nm).

  In the batch exposure step S4, in order to suppress the acid generation reaction in the pattern unexposed area, the exposure is performed with radiation having a wavelength longer than the wavelength of radiation that can be absorbed by the [A] polymer and the [B] sensitizer precursor. There is a need to. Considering these, the lower limit of the wavelength of the radiation (I) in the batch exposure is preferably 280 nm, and more preferably 320 nm. When generating a sensitizer capable of absorbing longer wavelengths of radiation, the wavelength of the non-ionizing radiation may be 350 nm or more. However, if the wavelength of the non-ionizing radiation is too long, the efficiency of the radiation sensitization reaction is reduced, so the wavelength of radiation that can be absorbed by the polymer component, the radiation sensitive acid generator, and the radiation sensitive sensitizer generator. It is desirable to use non-ionizing radiation having a wavelength as short as possible that can be absorbed by the sensitizer. From such a viewpoint, the upper limit of the wavelength of the radiation (I) is preferably 450 nm, and more preferably 400 nm.

  The pattern exposure step S3 and / or the collective exposure step S4 may be performed by immersion lithography (immersion exposure) or may be performed by dry lithography (dry exposure). Immersion lithography refers to exposure performed with a liquid interposed between a film (I) and a projection lens. In contrast, dry lithography refers to exposure performed in a state where a gas is interposed between the film (I) and the projection lens, under reduced pressure, or in a vacuum.

  The immersion lithography in the pattern exposure step S3 and / or the batch exposure step S4 is a liquid having a refractive index of 1.0 or more between the film (I) or protective film formed in the film formation step S2 and the projection lens. You may carry out in the state which intervened. The protective film is preferably for preventing reflection or improving reaction stability. The protective film preferably prevents liquid penetration, enhances water repellency on the film surface, and prevents defects due to liquid in immersion exposure.

  In the immersion lithography in the collective exposure step S4, the liquid has at least a wavelength of radiation (I) that is directly absorbed by the (a) radiation-sensitive acid-sensitizer generator or [E] radiation-sensitive acid generator. Some of them may be absorbed. By using the liquid in the immersion lithography, the radiation-sensitive acid generator or radiation-sensitive property remaining on the film (I) after the pattern exposure step S4 due to irradiation of the radiation (I) in the batch exposure step S4. Direct acid generation from the acid generating group can be further suppressed.

  When the pattern exposure step S3 and / or the batch exposure step S4 is performed by dry lithography, the pattern exposure step S3 and / or the batch exposure step S4 can be performed in the air, in a reduced pressure atmosphere, or in an inert atmosphere, but include a reduced pressure atmosphere or nitrogen or argon. It is preferable to carry out in an inert atmosphere. Furthermore, the upper limit of the concentration of the basic compound in the atmosphere during the implementation is preferably 20 ppb, more preferably 5 ppb, and even more preferably 1 ppb.

(Process S5: Baking process)
In the baking step S5, the film (I) after the batch exposure step S4 is heated (hereinafter also referred to as “post-flood exposure baking (PFEB)” or “post-exposure baking (PEB)”). In addition, when the pattern formation method of this embodiment is equipped with the baking process S3a after the said pattern exposure process S3 and before the said batch exposure process S4, the said baking process S3a may be called 1stPEB process, and the said baking process S5 may be called 2ndPEB process. (See FIG. 3). The heating condition can be, for example, 50 ° C. or higher and 200 ° C. or lower and 10 seconds or longer and 300 seconds or shorter in an atmosphere of an inert gas such as nitrogen or argon. By setting the heating condition within the above range, acid diffusion can be controlled, and the processing speed of the semiconductor wafer tends to be ensured. In the baking step S5, the acid generated in the pattern exposure step S3 and the batch exposure step S4 causes a polarity change reaction such as a deprotection reaction of the polymer [A] and a crosslinking reaction. Further, the side wall of the film (I) may be undulated due to the influence of the standing wave of radiation in the film (I), but in the baking step S5, the waving can be reduced by the diffusion of the reactant.

(Step S6: Development step)
In the developing step S6, the film (I) after the baking step S5 is brought into contact with the developer. The pattern is formed by utilizing the fact that the solubility in the developer is selectively changed in the pattern exposure portion by the reaction in the film (I) in the baking step S5. The developer can be divided into a positive developer and a negative developer.

  As the positive developer, an alkali developer is preferable. The alkaline developer selectively dissolves the highly polar part of the exposed film (I). Examples of the alkaline developer include potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines (ethanolamine, etc.), and tetraalkylammonium hydroxide (TAAH). . TAAH is preferred as the alkaline developer. As TAAH, for example, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, methyltriethylammonium hydroxide, trimethylethylammonium hydroxide, dimethyldiethylammonium hydroxide, water Trimethyl (2-hydroxyethyl) ammonium oxide (ie, choline), triethyl (2-hydroxyethyl) ammonium hydroxide, dimethyldi (2-hydroxyethyl) ammonium hydroxide, diethyldi (2-hydroxyethyl) ammonium hydroxide, hydroxylated Methyl tri (2-hydroxyethyl) ammonium, ethyl tri (2-hydroxyethyl) ammonium hydroxide, tetra (2-hydroxyethyl) ammonium hydroxide, etc. It is below.

  A 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) is widely used as a positive developer.

  In alkali development, a pattern is formed by utilizing a phenomenon in which carboxylic acids and hydroxyl groups generated in the film (I) after exposure are ionized and dissolved in an alkali developer. After the development, in order to remove the developer remaining on the substrate, a water washing process called rinsing is performed.

  An organic developer is preferred as the negative developer. The organic developer selectively dissolves the low-polarity portion of the exposed film (I). The organic developer is used to improve the resolution performance and the process window by removing patterns such as holes and trenches. In this case, the dissolution contrast between the pattern exposed portion and the pattern unexposed portion is obtained by the difference in affinity between the solvent in the film (I) and the organic developer. A portion having a high polarity has low solubility in an organic developer and remains as a pattern. Examples of the organic developer include 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methyl Acetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonic acid, ethyl crotonic acid , Methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate , Examples include methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenylacetate, and 2-phenylethyl acetate. .

  The pattern after the development step S6 (including rinse treatment) may be heated (sometimes referred to as post-baking). By post-baking, the rinse liquid remaining after the rinse treatment can be vaporized and removed, and the pattern can be cured.

(Step S7)
In step S7, a substrate pattern is formed by etching or ion implantation of the underlying substrate using the pattern after the developing step S6 as a mask. The etching may be dry etching under an atmosphere such as plasma excitation, or may be wet etching immersed in a chemical solution. After the substrate pattern is formed by etching, the pattern is removed.

  The pattern forming method according to the present embodiment includes the pattern exposure step S3 and the batch exposure step S4, so that the acid generated after the exposure can be greatly increased only in the pattern-exposed portion.

  FIG. 4 is a graph showing the absorbance of the pattern exposure portion of the film (I) and the absorbance of the unexposed portion during batch exposure. The portion of the film (I) where the pattern is not exposed (pattern unexposed portion) absorbs ultraviolet rays having a relatively short wavelength, but does not absorb ultraviolet rays having a long wavelength. On the other hand, as described above, acid and sensitizer are generated in the pattern-exposed portion (pattern exposed portion) of the film (I). The generated sensitizer absorbs radiation having a wavelength exceeding 250 nm and absorbs ultraviolet rays having a relatively long wavelength. In the batch exposure, radiation is irradiated to the entire surface of the film (I) without using a mask as in pattern exposure, but the radiation (I) is not absorbed in the batch exposure step S4 in the pattern unexposed portion. Therefore, in the collective exposure step S4, acid generation occurs in the pattern exposure portion. For this reason, an acid can be continuously generated only in the pattern exposure part during the batch exposure, and the sensitivity can be improved while maintaining the lithography characteristics. Moreover, since the radiation sensitive composition containing the [C] metal containing compound of this embodiment is used, the light absorption peak of the pattern exposure part in FIG. 4 by interaction with a sensitizer and a [C] metal containing compound is used. Shifts to the longer wavelength side, and the absorbance of the sensitizer increases at the wavelength at which batch exposure is performed. As a result, the sensitivity can be further improved.

  FIG. 5A is a conceptual diagram showing, as a graph, an acid concentration distribution obtained by a pattern formation method using a conventional chemically amplified resist material. When only pattern exposure is performed by EUV or the like as shown in FIG. 2, sufficient acid cannot be generated and sensitivity is lowered. When the exposure amount is increased in order to improve the sensitivity, the latent image of the pattern deteriorates (lithography characteristics are lowered), and it is difficult to achieve both sensitivity and lithography characteristics. FIG.5 (b) is a conceptual diagram which shows the sensitizer density distribution and acid concentration distribution by the pattern formation method using the radiation sensitive composition which concerns on this embodiment as a graph. In the pattern exposure, although the pattern latent image is excellent, sufficient acid is not generated. However, in the collective exposure, the absorbance of the wavelength (I) of the sensitizer is increased by the [C] metal-containing compound, so that a larger amount of acid is generated than in the conventional case. Therefore, after the collective exposure, the amount of acid can be greatly increased only at the pattern exposure portion, and the sensitivity can be improved with a small exposure while maintaining a latent image having an excellent pattern. Since the acid generation mechanism by the sensitizer during batch exposure occurs at room temperature, there is little blurring of the latent image at the time of acid generation, and a significant increase in sensitivity can be achieved while maintaining the resolution.

<Semiconductor devices>
The semiconductor device according to the present embodiment is manufactured using the pattern formed by the above method. FIG. 6 is a cross-sectional view showing an example of the manufacturing process of the semiconductor device of this embodiment.

  FIG. 6A is a cross-sectional view showing a pattern forming process, which is formed on the film to be etched 3 by the semiconductor wafer 1, the film to be etched 3 formed on the semiconductor wafer 1, and the pattern forming method. FIG. 6 is a cross-sectional view of the pattern 2 (corresponding to the end of the development step S6). Examples of the film to be etched include an active layer, a lower insulating film, a gate electrode film, and an upper insulating film. Between the film 3 to be etched and the pattern 2, an antireflection film, a lower layer film for improving the adhesion of the film (I), and a lower layer film for improving the shape of the film (I) may be provided. . A multilayer mask structure may be adopted. FIG. 6B is a cross-sectional view showing the etching process, and is a cross-sectional view of the semiconductor wafer 1, the pattern 2, and the etched film 3 etched using the pattern 2 as a mask. The etched film 3 is etched along the shape of the opening of the pattern 2. FIG. 6C is a cross-sectional view of the pattern substrate 10 including the semiconductor wafer 1 and the pattern of the etched film 3 after the pattern 2 is removed.

  A semiconductor device can be formed using a substrate having the pattern of the film 3 to be etched. As this formation method, for example, a method of embedding wiring between the patterns of the etching target film 3 from which the pattern 2 is removed, and further stacking device elements on the substrate can be cited.

<Lithography mask>
The lithography mask according to the present embodiment is manufactured by processing a substrate using the pattern formed by the above method. As this manufacturing method, the method of etching the hard mask formed in the glass substrate surface or the glass substrate surface using a pattern, for example is mentioned. Here, the lithography mask includes a transmissive mask using ultraviolet rays or an electron beam, a reflective mask using EUV light, and the like. When the lithography mask is a transmissive mask, it can be manufactured by masking the light shielding portion or the phase shift portion with a pattern and processing it by etching. Further, when the lithography mask is a reflective mask, it can be manufactured by processing the light absorber by etching using the pattern as a mask.

<Template for nanoimprint>
The nanoimprint template according to the present embodiment can also be manufactured using the pattern formed by the above method. Examples of the manufacturing method include a method of forming a pattern on a glass substrate surface or a hard mask surface formed on the glass substrate surface, and processing by etching.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples.

[Synthesis Example 1]
In 40 mL of 2-chloroethanol, 1.06 g of di-2-pyridyl ketone (S-1) and 12 g of lithium carbonate (Li ₂ CO ₃ ) were mixed and refluxed for 5 hours, and then the solvent was removed under reduced pressure. By performing column chromatography purification using alumina gel, a compound represented by the following formula (P-1) was obtained in a yield of 30%.

[Preparation Example 1]
Compound (S-1) was dissolved in acetonitrile to prepare a 0.0001 mass% solution.

[Preparation Example 2]
The compound (S-1) and copper (II) trifluoromethanesulfonate were mixed so as to be equimolar, and then dissolved in acetonitrile so as to be 0.0001% by mass based on the compound (S-1).

[Preparation Example 3]
Compound (P-1) was dissolved in acetonitrile to prepare a 0.0001 mass% solution.

[Preparation Example 4]
The compound (P-1) and copper (II) trifluoromethanesulfonate were mixed so as to be equimolar, and then dissolved in acetonitrile so as to be 0.0001% by mass based on the compound (P-1).

[Absorbance measurement]
About the solution prepared in the said preparation examples 1-4, the light absorbency was measured using the spectrophotometer ("V-670" of JASCO Corporation) by using acetonitrile as a reference solvent. The absorbance was determined by subtracting the absorbance of the reference solvent from the absorbance of the measurement solution at each wavelength of 250 nm to 600 nm. When the measured value of the absorbance in the entire wavelength region of the wavelength of 320 nm or more and 400 nm or less is less than 0.001, it is evaluated as “transparent”, and the wavelength at which the absorbance is 0.001 or more in the entire wavelength region is a little Was rated as “absorbed”. The evaluation results are shown in Table 1 below. In addition, it was confirmed that the transmittance of acetonitrile, which is a solvent used for the measurement of absorption spectrometry, was 95% or more in the entire wavelength region of wavelengths from 250 nm to 600 nm.

  As is clear from the results in Table 1, the ketone body used alone as a sensitizer does not have absorption at the batch exposure wavelength, but has absorption by mixing with a metal-containing component, while sensitization. The body precursor has no absorption at the batch exposure wavelength regardless of the presence or absence of the metal-containing component. Therefore, in the radiation-sensitive composition of the present invention containing both the sensitizer precursor and the metal-containing component, it is expected that the effect of increasing the sensitivity by combining the pattern exposure and the collective exposure is exhibited.

  When the radiation-sensitive composition of the present invention uses ionizing radiation such as EUV light having a wavelength of 250 nm or less, electron beam, ion beam, or non-ionizing radiation such as KrF excimer laser and ArF excimer laser as pattern exposure light. It is possible to exhibit excellent sensitivity. Moreover, the said radiation sensitive composition can be used suitably for the said pattern formation method.

1 Semiconductor wafer 2 Pattern 3 Etched film

Claims (5)

A polymer having a structural unit containing an acid dissociable group;
A sensitizer precursor that generates a sensitizer that absorbs first radiation having a wavelength greater than 250 nm upon exposure;
A metal-containing compound;
Containing a solvent and
The radiation-sensitive composition in which the sensitizer precursor contains at least one of the following components (a) and (b).
(A) When the second radiation having a wavelength of 250 nm or less is irradiated and the first radiation is not irradiated, an acid and the sensitizer are generated, and only the first radiation is not irradiated with the second radiation. Radiation-sensitive acid-sensitizer generator that does not substantially generate the acid and sensitizer when irradiated (b) When the second radiation is irradiated and the first radiation is not emitted, the sensitizer is A radiation-sensitive sensitizer generator that is generated and does not substantially generate the sensitizer when irradiated with only the first radiation without irradiating the second radiation.   The radiation-sensitive composition according to claim 1, further comprising a radiation-sensitive acid generator.   The radiation-sensitive composition according to claim 1 or 2, wherein the metal-containing compound is a transition metal-containing compound.   The radiation-sensitive composition according to claim 1, wherein the metal-containing compound is a complex or a salt. A film forming step of forming a film on at least one surface of the substrate using the radiation-sensitive composition according to any one of claims 1 to 4;
A pattern exposure step of irradiating the film with radiation having a wavelength of 250 nm or less;
A batch exposure step of irradiating the film after the pattern exposure step with radiation having a wavelength of more than 250 nm;
A baking step for heating the film after the batch exposure step;
A pattern forming method comprising: a developing step of bringing the film after the baking step into contact with a developer.

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