JP5548526B2 - Actinic ray or radiation sensitive resin composition and pattern forming method using the composition - Google Patents

Description

  The present invention relates to an actinic ray-sensitive or radiation-sensitive resin composition suitably used in an ultramicrolithography process such as the manufacture of VLSI and high-capacity microchips and other photofabrication processes, and pattern formation using the composition It is about the method. More specifically, the present invention relates to an actinic ray-sensitive or radiation-sensitive resin composition that can be suitably used for microfabrication of a semiconductor device using an electron beam, an X-ray, or EUV light (wavelength: around 13 nm) and the same. The present invention relates to a pattern forming method.

  In the present invention, “active light” or “radiation” means, for example, an emission line spectrum of a mercury lamp, far ultraviolet rays represented by excimer laser, extreme ultraviolet rays, X-rays, electron beams, and the like. In the present invention, light means actinic rays or radiation.

  Conventionally, in the manufacturing process of semiconductor devices such as IC and LSI, fine processing by lithography using a photoresist composition has been performed. In recent years, with the high integration of integrated circuits, the formation of ultrafine patterns in the submicron region and the quarter micron region has been required. Along with this, there is a tendency to shorten the exposure wavelength from g-line to i-line and further to KrF excimer laser light. Furthermore, at present, in addition to excimer laser light, lithography using electron beams, X-rays, or EUV light is also being developed.

  These electron beams, X-rays, or EUV light lithography are positioned as next-generation or next-generation pattern forming technologies, and resists with high sensitivity and high resolution are desired.

  High sensitivity is a very important issue especially for shortening the wafer processing time, but when trying to increase the sensitivity, not only the resolution but also the line width roughness deteriorates. Development of a resist that satisfies the characteristics at the same time is strongly desired.

  Here, line width roughness means that when the pattern is viewed from directly above because the resist pattern and the edge of the substrate interface vary irregularly in the direction perpendicular to the line direction due to the characteristics of the resist. Say that the edges look uneven. The unevenness is transferred by an etching process using a resist as a mask, and the electrical characteristics are deteriorated, so that the yield is lowered.

  High sensitivity, high resolution, good pattern shape, and good line width roughness are in a trade-off relationship, and it is very important how to satisfy these simultaneously.

  As a resist suitable for a lithography process using such electron beam, X-ray or EUV light, a chemically amplified positive resist mainly utilizing an acid catalyst reaction has been studied from the viewpoint of high sensitivity, and an alkali as a main component. Chemical amplification type consisting of a phenolic resin (hereinafter abbreviated as phenolic acid-decomposable resin) that is insoluble or sparingly soluble in a developer and soluble in an alkali developer by the action of an acid, and an acid generator A positive resist composition is used.

  With respect to these positive resists, several resist compositions using a phenolic acid-decomposable resin copolymerized with an acid-decomposable acrylate monomer have been known so far. For example, positive resist compositions disclosed in Patent Documents 1 to 4 can be exemplified.

  However, for practical use, further improvements in performance such as sensitivity, resolution in various circuit patterns, exposure margin, and line width roughness (LWR) are required. There is also a need for these improvements in bridge margin and isolated space resolution.

  Here, the exposure margin means that the pattern size is stably maintained when the exposure amount changes. If the exposure margin is sufficient, the resolution performance is stabilized and the yield is not reduced.

US Pat. No. 5,561,194 JP-A-8-101509 JP 2000-347405 A JP 2004-210803 A

  An object of the present invention is to solve the problem of performance improvement technology in microfabrication of a semiconductor device using high energy rays, X-rays, electron beams or EUV light, and has high sensitivity, high density pattern and high resolution of isolated lines. An actinic ray-sensitive or radiation-sensitive resin composition that simultaneously satisfies image quality, sufficient exposure margin, good line width roughness, good bridge margin, and high resolution of an isolated space, and a pattern forming method using the same It is to provide.

  Here, in order to resolve a pattern in which the entire periphery is exposed like an isolated line, it is important to sufficiently suppress the diffusion of the acid generated by the exposure. When acid diffusion suppression is insufficient, isolated lines are not formed due to acid diffusion from the exposed portion.

  As a result of intensive studies, the present inventors have found that a pattern is formed using an actinic ray-sensitive or radiation-sensitive resin composition containing a polymer containing a unit having a specific structure and an acid generator that generates an acid having a specific structure. It was found that the above-mentioned purpose is achieved.

That is, the present invention is as follows.
(1) (A) a resin containing a unit represented by general formula (AI) and a unit represented by general formula (AII), which increases the solubility in an alkaline developer by the action of an acid, and (B) An actinic ray-sensitive or radiation-sensitive resin composition comprising a compound that generates an acid having a structure represented by the general formula (BI) upon irradiation with an actinic ray or radiation.

In general formula (AI),
Rx represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.

T represents a single bond or a divalent linking group.
Rx ₁ represents an alkyl group (linear or branched), or monocyclic cycloalkyl group.
Z and C form a monocyclic cycloalkyl group having 5 to 8 carbon atoms.
In general formula (AII):
Rx represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.

Rx ₂ represents a hydrogen atom or an organic group, and Rx ₃ represents a non-acid-decomposable group.
m is an integer of 1 to 4, n is an integer of 0 to 4, and 1 ≦ n + m ≦ 5. When m is 2 to 4, the plurality of Rx ₂ may be the same or different, and when n is 2 to 4, the plurality of Rx ₃ may be the same or different.
In general formula (BI):
Ar represents an aromatic ring and may further have a substituent in addition to the A group.
p represents an integer of 1 or more.
A represents a group having a hydrocarbon group having 3 or more carbon atoms.
When p is 2 or more, the plurality of A groups may be the same or different.

  (2) The actinic ray-sensitive or radiation-sensitive resin composition according to (1), wherein in general formula (BI), A is a group having a hydrocarbon group having 4 or more carbon atoms.

  (3) The actinic ray-sensitive or radiation-sensitive resin composition according to (1), wherein in general formula (BI), A is a group having a cyclic hydrocarbon group having 4 or more carbon atoms.

  (4) The actinic ray-sensitive or radiation-sensitive resin composition according to (1), wherein in general formula (BI), A is a group having a cyclohexyl group.

(5) In the general formula (BI), Ar represents a benzene ring, p represents an integer of 2 or more, and two A groups out of two or more A groups are each ortho-positioned with respect to the —SO ₃ H group. The actinic ray or sensation according to any one of (1) to (4), wherein the carbon atom adjacent to Ar in the A group is a tertiary or quaternary carbon atom. Radiation resin composition.

  (6) In the general formula (BI), the group represented by Ar has a hydrocarbon group having 1 or more carbon atoms as a substituent other than the A group, a halogen atom, a hydroxyl group, a carboxyl group, a cyano group. And the actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (5), which has at least one substituent selected from nitro groups.

(7) The actinic ray or sensation according to any one of (1) to (6), wherein the unit represented by formula (AI) is a structure represented by formula (AI-1) Radiation resin composition.

  In general formula (AI-1), Rx and T represent the same meaning as in general formula (AI).

(8) The actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (7), further comprising a surfactant having a structure represented by the general formula (II) object.

In general formula (II):
R ₁₀ represents a hydrogen atom or an alkyl group.
Rf represents a fluoroalkyl group or a fluoroalkylcarbonyl group.
m represents an integer of 1 to 50.

  (9) Forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (8), exposing the film, and developing the exposed film Pattern forming method.

  (10) The pattern forming method according to (9), wherein the exposure light source is an electron beam, an X-ray or EUV light.

  According to the present invention, high sensitivity, high density pattern and high resolution of isolated lines, sufficient exposure margin, good line width roughness, good bridge margin and high sensitivity of isolated space satisfying high resolution of isolated space at the same time Alternatively, it is possible to provide a radiation-sensitive resin composition and a pattern forming method using the same.

Hereinafter, the actinic ray-sensitive or radiation-sensitive resin composition of the present invention and a pattern forming method using the same will be described in detail.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what does not have a substituent and what has a substituent. . For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

[Actinic ray or radiation sensitive resin composition]
[1] (A) Resin whose solubility in alkali developer is increased by the action of acid The resin of component (A) is a resin whose solubility in alkali developer is increased by the action of acid, and the main chain or side chain of the resin Alternatively, it is a resin having a group (hereinafter also referred to as “acid-decomposable group”) that decomposes by the action of an acid to generate an alkali-soluble group in both the main chain and the side chain.

  Preferred examples of the alkali-soluble group include a carboxyl group, a fluorinated alcohol group (preferably hexafluoroisopropanol), and a sulfonic acid group.

  A preferable group as the acid-decomposable group is a group obtained by substituting the hydrogen atom of these alkali-soluble groups with a group capable of leaving with an acid.

The resin of component (A) contains a repeating unit represented by the following general formula (AI) as a repeating unit having an acid-decomposable group.

In general formula (AI),
Rx represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.

T represents a single bond or a divalent linking group.
Rx ₁ represents an alkyl group (linear or branched), or monocyclic cycloalkyl group.
Z and C form a monocyclic cycloalkyl group having 5 to 8 carbon atoms.

  Examples of the divalent linking group for T include an alkylene group, —COO—Rt— group, —O—Rt— group, and the like. In the formula, Rt represents an alkylene group or a cycloalkylene group.

T is preferably a single bond or a —COO—Rt— group. Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a —CH ₂ — group or a — (CH ₂ ) ₃ — group.

The alkyl group for Rx ₁ is preferably a linear or branched group having 1 to 4 carbon atoms, and particularly preferably a methyl group or an ethyl group. The alkyl group may have a substituent. Examples of the substituent include a halogen atom, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, —OC (═O) Ra, —OC (═O). ORa, -C (= O) ORa, -C (= O) N (Rb) Ra, -N (Rb) C (= O) Ra, -N (Rb) C (= O) ORa, -N (Rb ) SO ₂ Ra, —SRa, —SO ₂ Ra, —SO ₃ Ra, —SO ₂ N (Rb) Ra, and the like. Here, Ra and Rb are each independently a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 6 carbon atoms), a monocyclic or polycyclic cycloalkyl group (preferably having 5 to 12 carbon atoms). Represents one of the following.

The cycloalkyl group represented by Rx ₁ is preferably a monocyclic cycloalkyl group having 4 to 8 carbon atoms. The cycloalkyl group may have a substituent, and examples of the substituent include a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, —OC (═O) Ra, —OC (═O ) ORa, -C (= O) ORa, -C (= O) N (Rb) Ra, -N (Rb) C (= O) Ra, -N (Rb) C (= O) ORa, -N ( _{Rb) SO2Ra, -SRa, -SO 2} Ra, -SO 3 Ra, or, -SO ₂ N (Rb) Ra, and the like. Here, Ra and Rb are each independently a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 6 carbon atoms), a monocyclic or polycyclic cycloalkyl group (preferably having 5 to 12 carbon atoms). Represents one of the following.
The monocyclic cycloalkyl group formed by C and Z is preferably a monocyclic cycloalkyl group having 5 or 6 carbon atoms.

The following general formula (AI-1) is mentioned as one preferable form of general formula (AI). In the formula, Rx and T have the same meanings as in general formula (AI).

  As for the content rate of the repeating unit represented by general formula (AI) which has an acid-decomposable group, 10-50 mol% is preferable with respect to all the repeating units in resin (A), More preferably, it is 20-45 mol%. .

Although the specific example of the repeating unit which has a preferable acid-decomposable group is shown below, this invention is not limited to this. In the formula, Rx represents any of H, CH ₃ , CF ₃ , and CH ₂ OH. Rxa represents a linear or branched alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 4 to 8 carbon atoms which may have a substituent.

  In the present invention, the acid-decomposable group contains a repeating unit represented by the above general formula (AI), but may further contain other acid-decomposable repeating units.

The resin (A) of the present invention further contains a repeating unit represented by the formula (AII).

In the general formula (AII), Rx represents the same as Rx in the above formula (AI).
Rx ₂ represents a hydrogen atom or an organic group.
Rx ₃ represents a non-acid-decomposable group.
m is an integer of 1 to 4, n is an integer of 0 to 4, and 1 ≦ n + m ≦ 5. When m is 2 to 4, the plurality of Rx ₂ may be the same or different, and when n is 2 to 4, the plurality of Rx ₃ may be the same or different.

Rx ₂ is preferably a hydrogen atom. Moreover, when m ≧ 2, it is preferable that at least one of the plurality of Rx ₂ is a hydrogen atom.
If rx ₂ is an organic group or may be a non-acid-decomposable in acid decomposable.
Examples where rx ₂ is an acid-decomposable _{group, -C (Rx 21) (Rx} 22) (Rx 23), - CO-O-Rx 24, -C (Rx 25) (Rx 26) -O -Rx _{27 and the} like.
Here, RX _{21 to} Rx ₂₃ each independently represents an alkyl group or a cycloalkyl group, and any two of them may combine to form a ring structure.
Rx ₂₄ represents an alkyl group or a cycloalkyl group.
Rx ₂₅ and Rx ₂₆ each independently represent a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group.
Rx ₂₇ represents an organic group, an alkyl group, a cycloalkyl group, an aryl group, or an alkyl group substituted with a cycloalkyl group or an aryl group.

Examples of the case where Rx ₂ is a non-acid-decomposable group include a halogen atom, an alkyl group, and a cycloalkyl group (provided that the carbon atom adjacent to the oxygen atom is a tertiary carbon as the alkyl group and cycloalkyl group) And an aryl group, an acyl group, —C (═O) Ra, and —C (═O) ORb.
Here, Ra and Rb are each independently a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 6 carbon atoms), a monocyclic or polycyclic cycloalkyl group (preferably having 5 to 12 carbon atoms). Represents one of the following.

Examples of the non-acid-decomposable group for Rx ₃ include a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, —OC (═O) Ra, —OC (═O) ORa, —C (= O) ORa, -C ( = O) N (Rb) Ra, -N (Rb) C (= O) Ra, -N (Rb) C (= O) ORa, -N (Rb) SO 2 Ra _{, -SRa, -SO 2 Ra, -SO} 3 Ra, or, may be mentioned -SO ₂ N (Rb) Ra.
Here, Ra and Rb are each independently a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 6 carbon atoms), a monocyclic or polycyclic cycloalkyl group (preferably having 5 to 12 carbon atoms). Represents one of the following.

The preferable composition ratio in the resin (A) of the repeating unit represented by (AII) is 5 to 75 mol%, more preferably 20 to 70 mol% with respect to all the repeating units in the resin (A). .
It is preferable that the repeating unit represented by the formula (AII) is contained in the above range from the viewpoint of achieving both adhesion to the substrate and resolution.
Hereinafter, although the specific structure of the repeating unit represented by a formula (AII) is illustrated, it is not this limitation. In the formula, Rx represents any of H, CH ₃ , CF ₃ , and CH ₂ OH.

The resin used in the present invention may further contain, as units other than formulas (AI) and (AII), a repeating unit that does not exhibit acid decomposability and is represented by formula (AIII) or (AIV).

In general formula (AIII):
Rx represents a hydrogen atom, an alkyl group which may have a substituent, or a —CH ₂ —O—Rx ₅ group. In the formula, Rx ₅ represents a hydrogen atom, an alkyl group or an acyl group. Rx is preferably a hydrogen atom, a methyl group, a hydroxymethyl group or a trifluoromethyl group, particularly preferably a hydrogen atom or a methyl group.
Rx ₄ represents an alkyl group, a cycloalkyl group having 3 to 12 carbon atoms, cycloalkenyl group having 3 to 12 carbon atoms, an aryl group having 1 to 8 carbon atoms.

The cycloalkyl group and cycloalkenyl group represented by Rx ₄ are preferably a monocyclic cycloalkyl group and a cycloalkenyl group. Preferred monocyclic cycloalkyl groups and cycloalkenyl groups are monocyclic hydrocarbon groups having 3 to 7 carbon atoms.

The aryl group represented by Rx ₄ can further have a substituent. Examples of the substituent that may be included include a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, —OC (═O) Ra, —OC (═O) ORa, —C ( = O) ORa, -C (= O) N (Rb) Ra, -N (Rb) C (= O) Ra, -N (Rb) C (= O) ORa, -N (Rb) SO 2 Ra, _{-SRa, -SO 2 Ra, -SO 3} Ra, or, may be mentioned -SO ₂ N (Rb) Ra.
Here, Ra and Rb are each independently a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 6 carbon atoms), a monocyclic or polycyclic cycloalkyl group (preferably having 5 to 12 carbon atoms). Represents one of the following.

The alkyl group, cycloalkyl group and cycloalkenyl group represented by Rx ₄ may further have a substituent. Preferred substituents include a halogen atom, a phenyl group, a hydroxyl group protected with a protective group, and a protective group. And an amino group protected with a group. As for the cycloalkyl group and the cycloalkenyl group, examples of the substituent further include an alkyl group. As for the alkyl group, examples of the substituent further include a cycloalkyl group. Preferred halogen atoms include bromine, chlorine and fluorine atoms, and preferred alkyl groups include methyl, ethyl, butyl and t-butyl groups. The above alkyl group may further have a substituent, and the substituent that may further have a halogen atom, an alkyl group, a hydroxyl group protected with a protecting group, an amino protected with a protecting group The group can be mentioned.

Examples of the protecting group include an alkyl group, a cycloalkyl group, an aralkyl group, a substituted methyl group, a substituted ethyl group, an alkoxycarbonyl group, and an aralkyloxycarbonyl group. Preferred alkyl groups include alkyl groups having 1 to 4 carbon atoms, preferred substituted methyl groups include methoxymethyl, methoxythiomethyl, benzyloxymethyl, t-butoxymethyl, 2-methoxyethoxymethyl groups, and preferred substituted ethyl groups. 1-ethoxyethyl, 1-methyl-1-methoxyethyl, preferred acyl groups include formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, pivaloyl groups, etc., aliphatic acyl groups having 1 to 6 carbon atoms, alkoxycarbonyl Examples of the group include an alkoxycarbonyl group having 1 to 4 carbon atoms.
Specific examples of the repeating unit represented by the formula (AIII) are shown below, but are not limited thereto. In the following specific examples, Rx represents the same substituent as described above.

In general formula (AIV):
Rx represents the same as in general formula (AIII).
Rx ₆ represents a halogen atom, a cyano group, an acyl group, an alkyl group, an alkoxy group, an acyloxy group or an alkoxycarbonyl group, an aryl group.
p represents an integer of 0 to 5. When p is 2 or more, the plurality of Rx ₆ may be the same or different.

Rx ₆ is preferably an acyloxy group or an alkoxycarbonyl group, and more preferably an acyloxy group. Among the acyloxy groups (general formula -O-CO-Rx ₇ .Rx ₇ represented by an alkyl group), is preferably has 1 to 6 carbon atoms of Rx _7, carbon atoms Rx ₇ 1 to 3 Are more preferable, and those in which Rx ₇ has 1 carbon atom (that is, an acetoxy group) are particularly preferable.
p is preferably 0 to 2, more preferably 1 to 2, and still more preferably 1.

The Rx ₆ group may have a substituent, and preferred substituents include a hydroxyl group, a carboxyl group, a cyano group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), an alkoxy group (methoxy group). Ethoxy group, propoxy group, butoxy group, etc.). As for the cyclic structure, examples of the substituent further include an alkyl group (preferably having 1 to 8 carbon atoms).
Specific examples of the repeating unit represented by formula (AIV) are shown below, but are not limited thereto. In the following specific examples, Rx represents the same substituent as described above.

The content of the repeating unit represented by the formula (AIII) or (AIV) is preferably 0 to 40 mol%, more preferably 0 to 20 mol%, based on all repeating units in the resin (A).
Although the specific example of resin of the (A) component used by this invention below is shown, this invention is not limited to these.

  As for the content rate in the composition of this invention of resin (A), 50-99 mass% is preferable with respect to the total solid, More preferably, it is 70-95 mass%.

[2] (B) Acid generator The actinic ray-sensitive or radiation-sensitive resin composition of the present invention is a compound that generates an acid represented by the general formula (BI) upon irradiation with an actinic ray or radiation (hereinafter referred to as “acid”). Also referred to as a “generating agent”).

In formula (BI),
Ar represents an aromatic ring and may further have a substituent in addition to the A group.
p represents an integer of 1 or more.
A represents a group having a hydrocarbon group having 3 or more carbon atoms.
When p is 2 or more, the plurality of A groups may be the same or different.
General formula (BI) will be described in more detail.
As the aromatic ring represented by Ar, an aromatic ring having 6 to 30 carbon atoms is preferable.
Specifically, benzene ring, naphthalene ring, pentalene ring, indene ring, azulene ring, heptalene ring, indecene ring, perylene ring, pentacene ring, acetaphthalene ring, phenanthrene ring, anthracene ring, naphthacene ring, chrysene ring, triphenylene ring, Fluorene ring, biphenyl ring, pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, indolizine ring, indole ring, benzofuran ring, benzothiophene ring, Isobenzofuran ring, quinolidine ring, quinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinoxazoline ring, isoquinoline ring, carbazole ring, phenanthridine ring, acridine ring, phenanthroline ring, thianthrene ring, Road ring, xanthene ring, phenoxathiin ring, phenothiazine ring, phenazine ring, and the like, a benzene ring, a naphthalene ring, an anthracene ring are preferred, a benzene ring is more preferable.

  Examples of the substituent that the aromatic ring may have other than the A group include a group having a hydrocarbon group having 1 or more carbon atoms, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), hydroxyl group, A cyano group, a nitro group, a carboxyl group, etc. can be mentioned. Examples of the group having a hydrocarbon group having 1 or more carbon atoms include an alkoxy group such as a methoxy group, an ethoxy group, and a tert-butoxy group, an aryloxy group such as a phenoxy group and a p-tolyloxy group, a methylthioxy group, Alkylthiooxy groups such as ethylthioxy group and tert-butylthioxy group, arylthiooxy groups such as phenylthioxy group and p-tolylthioxy group, alkoxycarbonyl groups such as methoxycarbonyl group and butoxycarbonyl group, and aryloxycarbonyls such as phenoxycarbonyl group Groups, acetoxy groups, methyl groups, ethyl groups, propyl groups, butyl groups, heptyl groups, hexyl groups, dodecyl groups, 2-ethylhexyl groups and other linear alkyl groups and branched alkyl groups, vinyl groups, propenyl groups, hexenyl groups, etc. Alkenyl group, acetylene group Propynyl group, an alkynyl group such as hexynyl group, aryl groups such as phenyl and tolyl groups, a benzoyl group, an acetyl group, and the like acyl groups such as tolyl group. Moreover, when it has two or more substituents, at least two substituents may be bonded to each other to form a ring.

Examples of the hydrocarbon group in the group having a hydrocarbon group having 3 or more carbon atoms represented by A include an acyclic hydrocarbon group and a cyclic aliphatic group.
In one embodiment, the A group is a group having a hydrocarbon group having 4 or more carbon atoms, and in another embodiment, the group A is a group having a cyclic hydrocarbon group having 4 or more carbon atoms.
As the A group, the carbon atom adjacent to Ar is preferably a tertiary or quaternary carbon atom.
Examples of the acyclic hydrocarbon group as the A group include isopropyl group, t-butyl group, t-pentyl group, neopentyl group, s-butyl group, isobutyl group, isohexyl group, 3,3-dimethylpentyl group, 2- An ethylhexyl group etc. are mentioned. The upper limit of the number of carbon atoms of the acyclic hydrocarbon group is preferably 12 or less, more preferably 10 or less.

  Examples of the cycloaliphatic group as the A group include a cycloalkyl group such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group, an adamantyl group, a norbornyl group, a bornyl group, a camphenyl group, and a decahydronaphthyl group. , A tricyclodecanyl group, a tetracyclodecanyl group, a camphoroyl group, a dicyclohexyl group, a pinenyl group, and the like, and a cyclohexyl group is preferable. These groups may have a substituent. The upper limit of the carbon number of the cycloaliphatic group is preferably 15 or less, more preferably 12 or less.

When the acyclic hydrocarbon group or the cyclic aliphatic group has a substituent, examples of the substituent include halogen atoms such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, a methoxy group, and an ethoxy group. Group, alkoxy group such as tert-butoxy group, aryloxy group such as phenoxy group, p-tolyloxy group, alkylthioxy group such as methylthioxy group, ethylthioxy group, tert-butylthioxy group, phenylthioxy group, p-tolyloxy group Arylthiooxy group such as methoxycarbonyl group, butoxycarbonyl group such as butoxycarbonyl group, aryloxycarbonyl group such as phenoxycarbonyl group, acetoxy group, methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group , Dodecyl group, 2-ethylhexyl group, etc. And aryl groups such as branched alkyl groups, cyclic alkyl groups such as cyclohexyl groups, alkenyl groups such as vinyl groups, propenyl groups, and hexenyl groups, alkynyl groups such as acetylene groups, propynyl groups, and hexynyl groups, phenyl groups, and tolyl groups. Group, hydroxy group, carboxy group, sulfonic acid group, carbonyl group, cyano group and the like.
Specific examples of the cyclic aliphatic group or acyclic hydrocarbon group as A include the following.

Among the above, the following structures are more preferable from the viewpoint of suppressing acid diffusion.

  p represents an integer of 1 or more, and the upper limit is not particularly limited as long as it is a chemically possible number, but is preferably 1 to 3, and more preferably 2 to 3, from the viewpoint of suppressing acid diffusion.

From the viewpoint of suppressing acid diffusion, the A group preferably substitutes at least one o-position of the sulfonic acid group, and more preferably has a structure in which two o-positions are substituted.
In one embodiment, the acid generator (B) of the present invention is a compound that generates an acid represented by the following general formula (BII).

In the formula, A is the same as A in the general formula (BI), and two A may be the same or different. R _{1 to} R ₃ each independently represents a hydrogen atom, a group having a hydrocarbon group having 1 or more carbon atoms, a halogen atom, a hydroxyl group, a cyano group, or a nitro group. Specific examples of the hydrocarbon group having 1 or more carbon atoms include the same groups as those exemplified above.

Among the compounds that generate an acid represented by the general formula (BI) upon irradiation with actinic rays or radiation, preferred compounds include compounds having an ionic structure such as sulfonium salts and iodonium salts, oxime esters, imide esters, and the like. Those having an ionic compound structure are preferred. Examples of the compound having an ionic structure include compounds represented by the following general formulas (ZI) and (ZII).

In the general formula (ZI),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (ZI-1), (ZI-2), (ZI-3) and (ZI-4) described later. Can do.
Z ⁻ represents an anion structure of an acid represented by the general formula (BI).

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, at least one of R _{201 to} R ₂₀₃ of the compound represented by the general formula (ZI) is a single bond or at least one of R _{201 to} R ₂₀₃ of another compound represented by the general formula (ZI) It may be a compound having a structure bonded through a linking group.

  More preferred (ZI) components include compounds (ZI-1), (ZI-2), (ZI-3) and (ZI-4) described below.

The compound (ZI-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compounds, namely, compounds containing an arylsulfonium as a cation.

In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be an aryl group with the remaining being an alkyl group or a cycloalkyl group.

  Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.

  The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. The aryl group may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the heterocyclic structure include a pyrrole residue, a furan residue, a thiophene residue, an indole residue, a benzofuran residue, and a benzothiophene residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.

The alkyl group or cycloalkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, such as a methyl group, Examples thereof include an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.
Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, more preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (ZI-2) will be described.
Compound (ZI-2) is a compound in which R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, 2-oxocycloalkyl group, alkoxy group. A carbonylmethyl group, particularly preferably a linear or branched 2-oxoalkyl group.

The alkyl group and cycloalkyl group of R ₂₀₁ to R _203, preferably a linear or branched alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups of several 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group). More preferred examples of the alkyl group include a 2-oxoalkyl group and an alkoxycarbonylmethyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

The 2-oxoalkyl group may be either linear or branched, and a group having> C = O at the 2-position of the above alkyl group is preferable.
The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the cycloalkyl group.

The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

The compound (ZI-3) is a compound represented by the following general formula (ZI-3), and is a compound having a phenacylsulfonium salt structure.

In the general formula (ZI-3), R _{1c to} R _5c each independently represent a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 12 carbon atoms), a cycloalkyl group (having 3 to 3 carbon atoms). 8 is preferred), a straight-chain or branched alkoxy group (in the case of straight-chain, preferably having 1 to 12 carbon atoms, and in the case of branching having 3 to 8 carbon atoms), or a halogen atom.

R _6c and R _7c each independently represent a hydrogen atom, a linear or branched alkyl group (preferably having 1 to 12 carbon atoms) or a cycloalkyl group (preferably having 3 to 8 carbon atoms).
R _x and R _y each independently represents a linear or branched alkyl group (preferably having 1 to 12 carbon atoms), a cycloalkyl group (preferably having 3 to 8 carbon atoms), an allyl group or a vinyl group.

Any two or more of R _{1c to} R _5c , R _6c and R _7c , and R _x and R _y may be bonded to each other to form a ring structure, and this ring structure includes an oxygen atom and a sulfur atom. , An ester bond and an amide bond may be included.
Zc ⁻ represents an anion structure of an acid represented by the same general formula (BI) as Z ⁻ .

Preferable specific examples of the compound (ZI-3) include those described in JP-A-2004-233661, paragraphs 0047 and 0048, JP-A-2003-35948, paragraphs 0040 to 0046 and US2003 / 0224288A1. -1) to (I-70), exemplified as formulas (IA-1) to (IA-54) and formulas (IB-1) to (IB-24) in US2003 / 0077540A1 And the like.
Zc ⁻ represents an anion structure of an acid represented by the same general formula (BI) as Z ⁻ .
The compound (ZI-4) is a compound represented by the following general formula (ZI-4).

In general formula (ZI-4),
R ₁₃ represents a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, or an alkoxycarbonyl group.
When a plurality of R ₁₄ are present, each independently represents an alkyl group, a cycloalkyl group, an alkoxy group, an alkylsulfonyl group, or a cycloalkylsulfonyl group.
R ₁₅ each independently represents an alkyl group or cycloalkyl. Two R ₁₅ may be bonded to each other to form a ring.
l represents an integer of 0-2.
r represents an integer of 0 to 8.
Z ⁻ represents an anion structure of an acid represented by the general formula (BI).

In the general formula (ZI-4), the alkyl group of R ¹³ , R ¹⁴ and R ¹⁵ is linear or branched and preferably has 1 to 10 carbon atoms, and is preferably a methyl group, an ethyl group, n -Propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, n-heptyl group, n -An octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group etc. can be mentioned. Of these alkyl groups, a methyl group, an ethyl group, an n-butyl group, a t-butyl group, and the like are preferable.

As a cycloalkyl group of R <_13> , R <_14> and R < ₁₅ >, a C3-C8 monocyclic thing is preferable. Particularly preferred are cyclopropyl, cyclopentyl, cyclohexyl and cyclooctyl.

The alkoxy group for R ₁₃ and R ₁₄ is linear or branched and preferably has 1 to 10 carbon atoms. In particular, methoxy group, ethoxy group, n-propoxy group, n-butoxy group and the like are preferable.

The alkoxycarbonyl group for R ₁₃ is linear or branched and preferably has 2 to 11 carbon atoms. In particular, a methoxycarbonyl group, an ethoxycarbonyl group, an n-butoxycarbonyl group, and the like are preferable.

The alkylsulfonyl group and cycloalkylsulfonyl group for R ₁₄ are linear, branched, or cyclic, and preferably have 1 to 10 carbon atoms. Of these alkylsulfonyl groups, a methanesulfonyl group, an ethanesulfonyl group, an n-propanesulfonyl group, an n-butanesulfonyl group, a cyclopentanesulfonyl group, a cyclohexanesulfonyl group, and the like are preferable.
As r, 0-2 are preferable.

As the ring structure that two R ₁₅ may be bonded to each other, a 5- or 6-membered ring, particularly preferably a 5-membered ring (that is, a 5-membered ring together with the sulfur atom in the general formula (ZI-4) (that is, A divalent group in which the two R ₁₅ are bonded to each other to form these ring structures.

As R ₁₅ in the general formula (ZI-4), a methyl group, an ethyl group, a phenyl group, a 4-methoxyphenyl group, a 1-naphthyl group, and two R ₁₅ are bonded to each other to form a tetrahydrothiophene ring structure together with a sulfur atom. A divalent group or the like that forms is preferable. Examples of the substituent for the divalent group include a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an alkoxy group, an alkalkyl group, an alkoxycarbonyl group, and an alkoxycarbonyloxy group.
Next, general formula (ZII) will be described.
In formula _{(ZII), R 204, R} 205 each independently represents an aryl group, an alkyl group or a cycloalkyl group.
The aryl group, alkyl group, and cycloalkyl group of R ₂₀₄ and R ₂₀₅ are the same as the groups described as the aryl group, alkyl group, and cycloalkyl group of R _{201 to} R ₂₀₃ in the aforementioned compound (ZI-1). is there.

Aryl group, alkyl group of R ₂₀₄ to R _205, cycloalkyl groups may have a substituent. Even the substituent, an aryl group of R ₂₀₁ to R ₂₀₃ in the compound of the aforementioned (ZI-1), an alkyl group, a cycloalkyl group are the same as those of the substituent which may have.
Z ⁻ represents an anion structure of an acid represented by the general formula (BI).
Specific examples of the compound capable of generating an acid represented by formula (BI) are shown below.

In addition, in this application, you may use multiple types of compounds which generate | occur | produce the acid represented by general formula (BI).
The content of the compound capable of generating an acid represented by the general formula (BI) is preferably 0.1 to 20% by mass, more preferably 1 to 18% by mass, based on the total solid content in the composition of the present invention. More preferably, it is 5-15 mass%.

Moreover, in this application, acid generators other than the acid generator which generate | occur | produces the acid represented by general formula (BI) can also be used together. Examples of this include, for example, in the formulas (ZI) and (ZII), Z ⁻ does not apply to the anion structure of the general formula (BI), alkyl sulfonate anion, aryl sulfonate anion, bis (alkylsulfonyl) imide anion, tris And those that are (alkylsulfonyl) methide anions. The alkyl group or aryl group in these anions may be substituted with a fluorine atom or the like. Specific examples include acid generators described in [0150] of US Patent Application Publication No. 2008/0248425.

[3] (C) Organic basic compound The composition of the present invention preferably contains a basic compound.
The basic compound is preferably a nitrogen-containing organic basic compound.
Although the compound which can be used is not specifically limited, For example, the compound classified into the following (1)-(4) is used preferably.
(1) Compound represented by the following general formula (BS-1)

In general formula (BS-1),
Each R independently represents a hydrogen atom, an alkyl group (straight or branched), a cycloalkyl group (monocyclic or polycyclic), an aryl group, or an aralkyl group. However, not all three Rs are hydrogen atoms.
Although carbon number of the alkyl group as R is not specifically limited, Usually, 1-20, Preferably it is 1-12.
Although carbon number of the cycloalkyl group as R is not specifically limited, Usually, 3-20, Preferably it is 5-15.
Although carbon number of the aryl group as R is not specifically limited, Usually, 6-20, Preferably it is 6-10. Specific examples include a phenyl group and a naphthyl group.
Although carbon number of the aralkyl group as R is not specifically limited, Usually, 7-20, Preferably it is 7-11. Specific examples include a benzyl group.

In the alkyl group, cycloalkyl group, aryl group or aralkyl group as R, a hydrogen atom may be substituted with a substituent. Examples of the substituent include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, a hydroxyl group, a carboxyl group, an alkoxy group, an aryloxy group, an alkylcarbonyloxy group, and an alkyloxycarbonyl group.
In the compound represented by the general formula (BS-1), it is preferable that only one of three Rs is a hydrogen atom, or all Rs are not hydrogen atoms.

Specific examples of the compound of the general formula (BS-1) include tri-n-butylamine, tri-n-pentylamine, tri-n-octylamine, tri-n-decylamine, triisodecylamine, dicyclohexylmethylamine, Tetradecylamine, pentadecylamine, hexadecylamine, octadecylamine, didecylamine, methyloctadecylamine, dimethylundecylamine, N, N-dimethyldodecylamine, methyldioctadecylamine, N, N-dibutylaniline, N, N- Examples include dihexylaniline.
In addition, a compound in which at least one R in the general formula (BS-1) is an alkyl group substituted with a hydroxyl group can be mentioned as one of preferable embodiments. Specific examples of the compound include triethanolamine and N, N-dihydroxyethylaniline.

The alkyl group as R may have an oxygen atom in the alkyl chain, and an oxyalkylene chain may be formed. The oxyalkylene chain is preferably —CH ₂ CH ₂ O—. Specific examples include tris (methoxyethoxyethyl) amine and compounds exemplified in column 3, line 60 of US Pat. No. 6,040,112.

(2) Compound having a nitrogen-containing heterocyclic structure The heterocyclic structure may or may not have aromaticity. Moreover, you may have two or more nitrogen atoms, Furthermore, you may contain hetero atoms other than nitrogen. Specifically, compounds having an imidazole structure (2-phenylbenzimidazole, 2,4,5-triphenylimidazole, etc.), compounds having a piperidine structure (N-hydroxyethylpiperidine, bis (1,2,2,6) , 6-pentamethyl-4-piperidyl) sebacate), compounds having a pyridine structure (such as 4-dimethylaminopyridine), and compounds having an antipyrine structure (such as antipyrine and hydroxyantipyrine).
A compound having two or more ring structures is also preferably used. Specific examples include 1,5-diazabicyclo [4.3.0] non-5-ene and 1,8-diazabicyclo [5.4.0] -undec-7-ene.

(3) Amine compound having a phenoxy group An amine compound having a phenoxy group has a phenoxy group at the terminal opposite to the nitrogen atom of the alkyl group of the amine compound. Examples of the phenoxy group include an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a carboxyl group, a carboxylic acid ester group, a sulfonic acid ester group, an aryl group, an aralkyl group, an acyloxy group, and an aryloxy group. It may have a substituent.
More preferably, it is a compound having at least one oxyalkylene chain between the phenoxy group and the nitrogen atom. The number of oxyalkylene chains in one molecule is preferably 3-9, more preferably 4-6. Among the oxyalkylene chains, —CH ₂ CH ₂ O— is preferable.

  Specific examples include 2- [2- {2- (2,2-dimethoxy-phenoxyethoxy) ethyl} -bis- (2-methoxyethyl)]-amine, and paragraph [0066] of US2007 / 0224539A1. And compounds (C1-1) to (C3-3) exemplified in the above.

(4) Ammonium salt ammonium salt derived from any of the compounds (1) to (3) is also used as appropriate. Preferred is hydroxide or carboxylate. More specifically, tetraalkylammonium hydroxide represented by tetrabutylammonium hydroxide is preferable.
In addition, compounds synthesized in Examples of JP-A No. 2002-363146, compounds described in paragraph 0108 of JP-A No. 2007-298869, and the like can also be used.

A basic compound is used individually or in combination of 2 or more types.
The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of solid content of a composition, Preferably it is 0.01-5 mass%.
The molar ratio of acid generator / basic compound is preferably 2.5 to 300. That is, the molar ratio is preferably 2.5 or more from the viewpoints of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing the reduction in resolution due to pattern thickening over time until post-exposure heat treatment. This molar ratio is more preferably 5.0 to 200, and still more preferably 7.0 to 150.

[4] Solvent The solvent that can be used in preparing the composition is not particularly limited as long as it dissolves each component. For example, alkylene glycol monoalkyl ether carboxylate (such as propylene glycol monomethyl ether acetate), alkylene Glycol monoalkyl ether (such as propylene glycol monomethyl ether), alkyl lactate ester (such as ethyl lactate and methyl lactate), cyclic lactone (such as γ-butyrolactone, preferably 4 to 10 carbon atoms), chain or cyclic ketone (2- Heptanone, cyclohexanone, etc., preferably 4 to 10 carbon atoms, alkylene carbonate (ethylene carbonate, propylene carbonate, etc.), alkyl carboxylate (preferably alkyl acetate such as butyl acetate), alkoxy And alkyl acetate (ethyl ethoxypropionate) and the like. Examples of other usable solvents include those described in US 2008/0248425 A1 [0244] and thereafter.

  Among the above, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, and lactic acid alkyl ester are preferable.

  These solvents may be used alone or in combination of two or more. When mixing 2 or more types, it is preferable to mix the solvent which has a hydroxyl group, and the solvent which does not have a hydroxyl group. The mass ratio of the solvent having a hydroxyl group and the solvent having no hydroxyl group is from 1/99 to 99/1, preferably from 10/90 to 90/10, and more preferably from 20/80 to 60/40.

  As the solvent having a hydroxyl group, alkylene glycol monoalkyl ether and alkyl lactate are preferred, and as the solvent having no hydroxyl group, alkylene glycol monoalkyl ether carboxylate is preferred.

  The amount of the solvent used can be appropriately adjusted according to the film thickness at the time of use, but generally, the total solid concentration in the composition is 0.5 to 30% by mass, preferably 1.0 to It is preferably used in an amount of 25% by mass, more preferably 1.5 to 20% by mass.

[5] Surfactant The composition of the present invention preferably further contains a surfactant. As the surfactant, fluorine-based and / or silicon-based surfactants are preferable.
Surfactants corresponding to these include Megafac F176, Megafac R08 manufactured by Dainippon Ink and Chemicals, PF656, PF6320 manufactured by OMNOVA, Troisol S-366 manufactured by Troy Chemical, Sumitomo 3M Examples include Fluorad FC430 manufactured by Co., Ltd., polysiloxane polymer KP-341 manufactured by Shin-Etsu Chemical Co., Ltd., and the like.

  Further, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. More specific examples include polyoxyethylene alkyl ethers and polyoxyethylene alkyl aryl ethers.

In addition, known surfactants can be used as appropriate. Examples of the surfactant that can be used include surfactants described in US 2008/0248425 A1 after [0273].
As the surfactant used in the present invention, a surfactant having a structure represented by the formula (II) is particularly preferable.

In general formula (II):
R ₁₀ represents a hydrogen atom or an alkyl group.
Rf represents a fluoroalkyl group or a fluoroalkylcarbonyl group.
m represents an integer of 1 to 50.

In the general formula (II), the fluoroalkyl group represented by Rf may have an oxygen atom or a double bond in the alkyl chain. For _{example, -CF 3, - C 2 F} 5, -C 4 F 9, -CH 2 CF 3, -CH 2 C 2 F 5, -CH 2 C 3 F 7, -CH 2 C 4 F 9, -CH _{2 C 6 F 13, -C 2} H 4 CF 3, -C 2 H 4 C 2 F 5, -C 2 H 4 C 4 F 9, -C 2 H 4 C 6 F 13, -C 2 H 4 C ₈ F ₁₇ , —CH ₂ CH (CH ₃ ) CF ₃ , —CH ₂ CH (CF ₃ ) ₂ , —CH ₂ CF (CF ₃ ) ₂ , —CH ₂ C
_{H (CF 3) 2, -CF} 2 CF (CF 3) OCF 3, -CF 2 CF (CF 3) OC 3 F 7, - C 2 H 4 OCF 2 CF (CF 3) OCF 3, -C 2 H _{4 OCF 2 CF (CF 3)} OC 3 F 7, -C (CF 3) = C (CF (CF 3) 2) 2 and the like.

Examples of the fluoroalkylcarbonyl group of Rf include —COCF ₃ , —COC ₂ F ₅ , —COC ₃ F ₇ , —COC ₄ F ₉ , —COC ₆ F ₁₃ , —COC ₈ F _{17 and the} like. .

The alkyl group as R ₁₀ preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms.
Hereinafter, although the specific example of surfactant represented by the said general formula (II) is given, it is not limited to these.

Surfactants may be used alone or in combination of two or more.
The amount of the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total solid content of the composition.
The use ratio of the surfactant represented by the formula (II) and the other surfactant is a mass ratio (surfactant represented by the general formula (II) / other surfactant). 40-99 / 1 is preferable and 70 / 30-99 / 1 is more preferable.

[6] Others In addition to the components described above, the composition of the present invention includes a carboxylic acid onium salt, a dissolution inhibiting compound having a molecular weight of 3000 or less, a dye, a plastic, and the like described in Proceeding of SPIE, 2724, 355 (1996). An agent, a photosensitizer, a light absorber, an antioxidant and the like can be appropriately contained.

[Pattern formation method]
The usage form of the actinic ray-sensitive or radiation-sensitive resin composition of the present invention will be described.
The pattern forming method of the present invention includes a step (1) of forming a film using an actinic ray-sensitive or radiation-sensitive resin composition, a step (2) of exposing the film, and a step of developing using an alkali developer after exposure. (4) and a baking (heating) step (3) may be included between the exposure step (2) and the development step (4).

(1) Film formation In order to obtain the actinic ray-sensitive or radiation-sensitive resin composition film of the present invention, each component is dissolved in a solvent, filtered as necessary, and then applied to a support (substrate). . The filter is preferably made of polytetrafluoroethylene, polyethylene, or nylon having a pore size of 0.1 μm or less, more preferably 0.05 μm or less, and still more preferably 0.03 μm or less.
The composition is applied by a suitable application method such as a spinner onto a substrate (eg, silicon, silicon dioxide coating) used in the manufacture of integrated circuit devices. Thereafter, it is dried to form a photosensitive film.
If necessary, a commercially available inorganic or organic antireflection film can be used. Furthermore, an antireflection film can be applied to the resist lower layer and used.

(2) Exposure The film obtained in the film forming process is irradiated with an electron beam or EUV light through a predetermined mask.

Note that in electron beam irradiation, drawing (direct drawing) without using a mask is common.

(3) Baking It is preferable to perform baking (heating) after exposure and before development.
The heating temperature is preferably 80 to 150 ° C, more preferably 90 to 150 ° C, and still more preferably 100 to 140 ° C.
The heating time is preferably 30 to 300 seconds, more preferably 30 to 180 seconds, and still more preferably 30 to 90 seconds.
Heating can be performed by means provided in a normal exposure / developing machine, and may be performed using a hot plate or the like.
The reaction of the exposed part is promoted by baking, and the sensitivity and pattern profile are improved.

(4) Alkali development The alkali developer used is an inorganic alkali such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, or ammonia water, or first such as ethylamine or n-propylamine. Secondary amines such as amines, diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium An aqueous solution (usually 0.1 to 20% by mass) of an alkali such as a quaternary ammonium salt such as hydroxide or choline, a cyclic amine such as pyrrole or piperidine, or the like can be used. Furthermore, an appropriate amount of an alcohol such as isopropyl alcohol or a nonionic surfactant may be added to the alkaline aqueous solution.

Among these developers, quaternary ammonium salts are preferable, and tetramethylammonium hydroxide and choline are more preferable.
The pH of the alkali developer is usually 10-15.
As a developing method, for example, a method in which a substrate is immersed in a tank filled with a developer for a certain period of time (dip method), a method in which the developer is raised on the surface of the substrate by surface tension and is left stationary for a certain time (paddle) Method), a method of spraying the developer on the substrate surface (spray method), a method of continuously applying the developer while scanning the developer application nozzle at a constant speed on a substrate rotating at a constant speed (dynamic dispensing method) ) Etc. can be applied.
In addition, after the step of performing development, a step of stopping development may be performed while substituting with pure water.
The development time is preferably a time during which an unexposed resin, a crosslinking agent and the like are sufficiently dissolved, and usually 10 seconds to 300 seconds. More preferably, it is 20 seconds to 120 seconds.
The temperature of the developer is preferably 0 ° C to 50 ° C, more preferably 15 ° C to 35 ° C.

(1) Synthesis of Synthesis Example 1 (P-1) 600 g of ethylene glycol monoethyl ether acetate was placed in a 2 L flask, and the atmosphere was purged with nitrogen at a flow rate of 100 mL / min for 1 hour. In addition, 105.4 g (0.65 mol) of 4-acetoxystyrene, 63.8 g (0.35 mol) of 1-ethylcyclopentyl methacrylate, 4.60 g of a polymerization initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) 0.02 mol) was dissolved in 200 g of ethylene glycol monoethyl ether acetate, and the resulting solution was purged with nitrogen as described above.

  A 2 L flask containing ethylene glycol monoethyl ether acetate was heated up to an internal temperature of 80 ° C., and then 2.30 g (0.01 mol) of a polymerization initiator V-601 was added and stirred for 5 minutes. . Thereafter, the monomer mixed solution was added dropwise over 6 hours with stirring. After the dropping, the mixture was further heated and stirred for 2 hours, and then the reaction solution was cooled to room temperature and dropped into 3 L of hexane to precipitate a polymer. The filtered solid was dissolved in 500 ml of acetone, dropped again into 3 L of hexane, and the filtered solid was dried under reduced pressure to obtain 145 g of 4-acetoxystyrene / 1-ethylcyclopentyl methacrylate copolymer.

  In the reaction vessel, 40.00 g of the polymer obtained above, 40 ml of methanol, 200 ml of 1-methoxy-2-propanol and 1.5 ml of concentrated hydrochloric acid were added, heated to 80 ° C. and stirred for 5 hours. The reaction solution was allowed to cool to room temperature and dropped into 3 L of distilled water. The filtered solid was dissolved in 200 ml of acetone, dropped again in 3 L of distilled water, and the filtered solid was dried under reduced pressure to obtain 35.5 g of polymer (A-6). The weight average molecular weight by GPC was 10800, and the molecular weight dispersity (Mw / Mn) was 1.65.

Resins (P-2) to (P-8) having the structures shown below were synthesized in the same manner as in Synthesis Example 1 except that the monomers used were changed. Table 1 shows the composition ratio, weight average molecular weight (Mw), and molecular weight dispersity (Mw / Mn) of the resin. The composition ratio (molar ratio) is the order of repeating units from the left in the resin structure shown below.

(2) EB exposure evaluation (2-1) Resist coating solution preparation and coating A resist solution was obtained by precisely filtering a coating solution composition having the composition shown in Table 2 with a membrane filter having a pore size of 0.1 μm. .
This resist solution was applied onto a 6-inch Si wafer subjected to HMDS treatment using a spin coater Mark8 manufactured by Tokyo Electron, and heated and dried on a hot plate having a temperature shown in Table 3 to form a resist film having a thickness of 0.12 μm. Obtained.

(2-2) EB exposure The resist film obtained in (2-1) above was subjected to pattern irradiation using an electron beam drawing apparatus (HL750 manufactured by Hitachi, Ltd., acceleration voltage 50 KeV). After irradiation, it was heated on a hot plate having the temperature shown in Table 3.
Subsequently, alkali development was performed using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide.
The obtained pattern was evaluated for sensitivity, resolution, exposure margin, and line width roughness by the following methods. The evaluation results are shown in Table 3 below.

(2-3-1) Sensitivity (E ₀ )
The obtained pattern was observed using a scanning electron microscope (S-9220 manufactured by Hitachi, Ltd.). The electron beam irradiation dose when resolving 0.10 μm (line: space = 1: 1) was defined as sensitivity (E ₀ ).

(2-3-2) Resolution (dense)
The limiting resolution (minimum line width at which lines and spaces are separated and resolved) at the exposure amount showing the above sensitivity was defined as the resolution (dense).

(2-3-3) Resolution (isolation)
Observed using a scanning electron microscope (S-9220 manufactured by Hitachi, Ltd.), an isolated line is formed at an electron beam irradiation amount when a 0.1 μm pattern of the isolated line (1:10 line space) is resolved. The minimum line width was defined as the resolution (isolation).

(2-3-4) Exposure margin When the sensitivity at which the pattern size is 0.09 μm is E ₁ and the sensitivity at which the pattern size is 0.11 μm is E ₂ , the numerical value obtained from the following formula is The exposure margin was taken.

Exposure margin = (E ₁ −E ₂ ) / E ₀ × 100 (%)
(2-3-5) Line width roughness (LWR)
The line width was measured at arbitrary 30 points in the length direction of 50 μm of the 0.10 μm line pattern at the irradiation dose showing the above sensitivity, and the variation was evaluated by 3σ.

(2-3-6) Bridge margin The exposure amount E ₀ (optimum exposure amount) for resolving the obtained 0.10 μm line-and-space resist pattern was measured using a scanning electron microscope (S-9220 manufactured by Hitachi, Ltd.). calculated to obtain the exposure amount E ₁ a bridge when a reduced amount of exposure from the exposure amount E ₀ is generated, and calculates a value obtained by the following formula 1, and it an indicator of the bridge margin.

Bridge margin (%) = [(E ₀ −E ₁ ) / E ₀ ] × 100 (1)
The larger the value calculated above, the better the performance.

(2-3-7) Isolated space resolution The 75 nm isolated space pattern was observed using a scanning microscope (S-9220 manufactured by Hitachi, Ltd.), and the minimum space width that could be resolved was defined as isolated space resolution.

  Hereinafter, the abbreviations in the table represent the above specific examples or the following.

<Acid generator>

<Organic basic compound>
D-1: Tetra- (n-butyl) ammonium hydroxide D-2: 1,8-diazabicyclo [5.4.0] -7-undecene D-3: 2,4,5-triphenylimidazole D-4 : Tridodecylamine <Surfactant>
W-1: PF636 (manufactured by OMNOVA)
W-2: PF6320 (made by OMNOVA)
W-3: PF656 (manufactured by OMNOVA)
W-4: PF6520 (made by OMNOVA)
W-5: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.)
W-6: Fluorard FC430 (manufactured by Sumitomo 3M)
<Coating solvent>
S-1: Propylene glycol monomethyl ether acetate (PGMEA)
S-2: Propylene glycol monomethyl ether (PGME)
S-3: Cyclohexanone S-4: Ethyl lactate

(3) KrF exposure evaluation (3-1) Resist coating solution preparation and coating A resist solution was obtained by precisely filtering a coating solution composition having the composition shown in Table 4 with a 0.1 μm pore size membrane filter. .
This resist solution was applied onto an 8-inch Si wafer on which a DUV42 (60 nm) base was applied using a spin coater Mark8 manufactured by Tokyo Electron, and heated and dried on a hot plate having a temperature shown in Table 5 to obtain a film thickness of 0. A resist film of 25 μm was obtained.

(3-2) KrF exposure The resist film obtained in (3-1) above was subjected to NA = 0.80, annular illumination, σ = 0.89 / using a KrF scanner (PAS5500 / 850 manufactured by ASML). Pattern irradiation was performed under an exposure condition of 0.59.
After irradiation, it was heated on a hot plate having the temperature shown in Table 5.
Then, after immersing for 60 seconds using 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution, it rinsed with water for 30 seconds and dried.

  The obtained pattern was evaluated by the following method. The evaluation results are shown in Table 5 below.

(3-3-1) Sensitivity (E ₀ )
The obtained pattern was observed using a scanning electron microscope (S-9220 manufactured by Hitachi, Ltd.). The irradiation dose when resolving 0.12 μm (line: space = 1: 1) was defined as sensitivity (E ₀ ).

(3-3-2) Exposure margin When the sensitivity at which the pattern size is 0.108 μm is E ₁ and the sensitivity at which the pattern size is 0.132 μm is E ₂ , the numerical values obtained from the following equations are The exposure margin was taken.

Exposure margin = (E ₁ −E ₂ ) / E ₀ × 100 (%)
(3-3-3) Line width roughness (LWR)
The line width was measured at arbitrary 30 points in the length direction of 50 μm of the 0.12 μm line pattern at the irradiation dose showing the above sensitivity, and the variation was evaluated by 3σ.

(3-3-4)
Bridge margin An exposure amount E ₀ (optimum exposure amount) for resolving the obtained 0.12 μm line-and-space resist pattern was calculated using a scanning electron microscope (S-9260, manufactured by Hitachi, Ltd.). An exposure amount E ₁ that generates a bridge when the exposure amount is reduced from ₀ is obtained, and a value obtained by the following equation 1 is calculated and used as an index of the bridge margin.

Bridge margin (%) = [(E ₀ −E ₁ ) / E ₀ ] × 100 (1)
The larger the value calculated above, the better the performance. The results are shown in Table 5.

(3-3-5) Isolated space resolution The 150 nm isolated space pattern was observed using a scanning microscope (S-9260 manufactured by Hitachi, Ltd.), and the minimum space width that could be resolved was defined as isolated space resolution.

The abbreviations in Table 4 represent the above specific examples.

(4) EUV exposure evaluation (4-1) Resist coating solution preparation and coating The coating solution composition shown in Table 6 was microfiltered with a membrane filter having a pore size of 0.1 μm to obtain a resist solution.

  This resist solution was applied onto a 6-inch Si wafer subjected to HMDS treatment using a spin coater Mark8 manufactured by Tokyo Electron and dried by heating on a hot plate having a temperature shown in Table 7 to form a resist film having a thickness of 0.05 μm. Got.

(4-2) EUV exposure The resist film was subjected to surface exposure using EUV light (wavelength 13 nm) while changing the exposure amount by 0.5 mJ in the range of 0 to 10.0 mJ.
After irradiation, it was heated on a hot plate having the temperature shown in Table 7.
Then, after immersing for 60 seconds using 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution, it rinsed with water for 30 seconds and dried.

  The obtained pattern was evaluated by the following method. The evaluation results are shown in Table 7 below.

(4-3-1) Sensitivity (Eth)
The exposure amount at which the resist film thickness after development was 50% of the film thickness before exposure was defined as sensitivity (Eth).

(4-3-2) Remaining film ratio A numerical value obtained from the following formula was defined as a remaining film ratio (%).
(Film thickness after unexposed area development / film thickness before exposure) × 100 (%)
(4-3-3) Surface roughness (Ra)
The surface roughness Ra (defined in JIS B0601) of the post-development resist film at the Eth sensitivity was observed using an atomic force microscope AFM (Dimension 3100 manufactured by Beiko Japan).

Abbreviations in Table 6 represent the above specific examples.

  From the results of Table 3, Table 5, and Table 7, it can be seen that the pattern obtained by the pattern forming method using the composition of the present invention has good performance.

Claims (13)

(A) a resin containing a unit represented by general formula (AI) and a unit represented by general formula (AII), which increases the solubility in an alkali developer by the action of an acid, and (B) actinic rays or An actinic ray-sensitive or radiation-sensitive resin composition comprising a compound having an ionic structure that generates an acid having a structure represented by General Formula (BI) upon irradiation with radiation.

In general formula (AI),
Rx represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
T represents a single bond or a divalent linking group.
Rx ₁ represents an alkyl group (linear or branched), or monocyclic cycloalkyl group.
Z and C form a monocyclic cycloalkyl group having 5 to 8 carbon atoms.
In general formula (AII):
Rx represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
Rx ₂ represents a hydrogen atom or an organic group, and Rx ₃ represents a non-acid-decomposable group.
m is an integer of 1 to 4, n is an integer of 0 to 4, and 1 ≦ n + m ≦ 5. When m is 2 to 4, the plurality of Rx ₂ may be the same or different, and when n is 2 to 4, the plurality of Rx ₃ may be the same or different.
In general formula (BI):
Ar represents an aromatic ring and may further have a substituent in addition to the A group.
p represents an integer of 1 or more.
A was tables a group having 4 or more cyclic hydrocarbon group of carbon, the carbon atom adjacent to Ar is a group a tertiary or quaternary carbon atoms. When p is 2 or more, the plurality of A groups may be the same or different.   The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, wherein the content of the unit represented by the general formula (AI) is 20 to 45 mol% with respect to all repeating units in the resin (A). The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2 , wherein the resin (A) further contains an acid-decomposable repeating unit in addition to the unit represented by the general formula (AI). The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 3 , wherein the compound (B) is represented by the general formula (ZI).

In general formula (ZI):
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group. Two members out of R _{201 to} R ₂₀₃ may combine to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.
Z ⁻ represents an anion structure of an acid represented by the general formula (BI). The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 4, wherein A is a group having a cyclic aliphatic group having 4 or more carbon atoms in the general formula (BI). 6. The actinic ray-sensitive or radiation-sensitive resin composition according to claim 5, wherein A is a cyclic aliphatic group having 4 or more carbon atoms in the general formula (BI). The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 4 , wherein A is a group having a cyclohexyl group in the general formula (BI). The actinic ray-sensitive or radiation-sensitive resin composition according to claim 7, wherein A is a cyclohexyl group in the general formula (BI). In the general formula (BI), Ar represents a benzene ring, p represents an integer of 2 or more, and of the two or more A groups, two A groups are each substituted at the ortho position based on the —SO ₃ H group. characterized that you have, actinic-ray- or radiation-sensitive resin composition according to any one of claims 1-8. In the general formula (BI), a group represented by Ar is a group having a hydrocarbon group having 1 or more carbon atoms as a substituent other than the A group, a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, and a nitro group. The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 9 , which has at least one substituent selected from: The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 10 , wherein the unit represented by the general formula (AI) is a structure represented by the formula (AI-1).

In general formula (AI-1), Rx and T represent the same meaning as in general formula (AI). A pattern forming method comprising forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 11 , exposing the film, and developing the exposed film. The pattern formation method according to claim 12 , wherein the exposure light source is an electron beam, an X-ray, or EUV light.