JP5740441B2 - Actinic ray-sensitive 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 a pattern forming method using the same More particularly, the present invention relates to a positive resist composition for electron beam, X-ray or EUV light, a pattern forming method using the same, and a resin used for the positive resist composition.

  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.

  In particular, lithography using an electron beam or EUV is positioned as a next-generation or next-generation pattern formation technology, and a positive resist with high sensitivity and high resolution is desired. In particular, high sensitivity is a very important issue for shortening the wafer processing time. However, when using chemically amplified resists, especially in lithography using electron beams or EUV, the sensitivity decreases and the shape of the resist pattern deteriorates. There is a problem that problems such as a decrease in resolution occur.

  One of the causes of such problems is contamination (environmental influence) on the resist layer of a basic substance such as amine existing in the environment. That is, in the chemically amplified resist, due to the reaction mechanism of utilizing the action of acid, the acid is deactivated by the contamination of the basic substance, and its performance (sensitivity, shape, resolution, etc.) is affected. In addition, such environmental influence is also caused by the length of the process delay, for example, the time from the application of the resist to the exposure and the time from the exposure to the post-exposure heating (PEB). The degree differs, and this causes a difference in performance between lots, and changes in sensitivity, shape, resolution, and the like. In particular, in lithography using an electron beam or EUV, since exposure is usually performed in a reduced pressure environment, it is necessary to perform a reduced pressure operation, a purge operation, or the like, so that the process delay is long and the environmental influence becomes a serious problem. With respect to such a problem, a protective film forming material for a resist layer used in electron beam or EUV lithography has been disclosed (Patent Document 1). That is, after forming a resist layer on a substrate, a protective film is formed on the resist layer using a protective film forming material, and the resist layer is selectively exposed with an electron beam or EUV through the protective film. Then, after performing PEB (post-exposure heating), the protective film is removed, and the resist layer is developed to form a resist pattern. However, a method of forming a protective film using such a protective film forming material requires a longer process, and a simpler and lower cost method is required.

  One of the other causes of the above-mentioned problems is the volatilization of basic substances and acids from the resist film. In ultrafine pattern formation of several tens of nanometers or less, volatilization of a very small amount of basic substance or acid in the process before exposure, during exposure, or after exposure causes a decrease in sensitivity, shape deterioration of the resist pattern, and resolution. This has a major impact on the decline of the product, and its improvement is an issue.

  Furthermore, the volatilization of the compound from the resist film causes contamination of the exposure apparatus which is very expensive as outgas, and the reduction of outgas from the resist film is also a very important issue. A solution is needed. Since both the electron beam and EUV lithography are required to be in a vacuum state, it is essential to solve this problem.

  In order to solve such a problem, it is disclosed that an EUV transmissive protective film (topcoat) having a EUV radiation transmittance higher than 50% made of a polymer including a group including boron is provided on a resist layer. (Patent Document 2). However, the method of forming a protective film using such a protective film forming material requires a longer process as described above, and a simpler and lower cost method is required.

JP 2006-58739 A Japanese Patent No. 4036849

  The object of the present invention is to simultaneously satisfy high sensitivity, high resolution, good pattern shape, good line edge roughness, and outgas reduction in an ultrafine region, particularly in electron beam, X-ray or EUV light lithography. Another object of the present invention is to provide a positive resist composition and a pattern forming method using the same.

As a result of intensive studies to solve the above problems, the present inventors have reached the present invention shown below.
(1) Resin having a repeating unit (A) that decomposes by irradiation with actinic rays or radiation to generate an acid and a repeating unit (B) that has a structure that decomposes by the action of an acid and increases solubility in an alkaline aqueous solution An actinic ray-sensitive or radiation-sensitive resin composition comprising (P) and a compound (U) that is unevenly distributed on the film surface by film formation to form a protective film.

  (2) The repeating unit (B) is a repeating unit having at least one group in which a hydrogen atom of a phenolic hydroxyl group is substituted with a group capable of leaving by the action of an acid. The actinic ray-sensitive or radiation-sensitive resin composition described.

(3) The actinic ray-sensitive or radiation-sensitive resin composition according to (1) or (2), wherein the repeating unit (B) is a repeating unit represented by the following general formula (I): object.

Here, R ₀₁ , R ₀₂ and R ₀₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl. Represents a group. R ₀₃ represents a substituted or unsubstituted alkylene group, and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n Y's each independently represent a hydrogen atom or a group capable of leaving by the action of an acid. However, at least one of Y represents a group capable of leaving by the action of an acid.
n represents an integer of 1 to 4.

(4) The actinic ray-sensitive or radiation-sensitive resin composition according to (3), wherein Y in the general formula (I) is represented by the following general formula (II).

Here, L ₁ and L ₂ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group. Represent.
M represents a single bond or a divalent linking group.
Q is a substituted or unsubstituted alkyl group, a substituted or unsubstituted alicyclic group which may contain a hetero atom, a substituted or unsubstituted aromatic ring group which may contain a hetero atom, substituted or unsubstituted It represents a substituted amino group, a substituted or unsubstituted ammonium group, a substituted or unsubstituted mercapto group, a cyano group, or a substituted or unsubstituted aldehyde group.
At least two of Q, M, and L ₁ may be bonded to form a 5-membered or 6-membered ring.

(5) The resin (P) has at least one repeating unit represented by the following general formulas (III) to (V) as the repeating unit (A), (1) to (4) The actinic ray-sensitive or radiation-sensitive resin composition according to any one of the above.

Here, R ₀₄ , R ₀₅ and R _{07 to} R ₀₉ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted group. Represents an alkoxycarbonyl group.
R ₀₆ represents a cyano group, a substituted or unsubstituted carboxyl group, —CO—OR ₂₅ or —CO—N (R ₂₆ ) (R ₂₇ ). R ₂₆ and R ₂₇ may combine to form a ring with the nitrogen atom.
X _{1 to} X ₃ are each independently a single bond, a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, —O—, —SO ₂ —, —CO -, -N (R _<33> )-or a divalent linking group in which a plurality of these are combined.
R ₂₅ represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group.
R ₂₆ , R ₂₇ and R ₃₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group or A substituted or unsubstituted aralkyl group is represented.
A represents a structural site that decomposes upon irradiation with actinic rays or radiation to generate an acid anion.

  (6) The actinic ray-sensitive or radiation-sensitive resin composition according to (5), wherein A in the general formulas (III) to (V) is a structural moiety containing a sulfonium salt or an iodonium salt. object.

  (7) The sensation according to any one of (1) to (6), wherein the repeating unit (A) has a structure in which an acid anion is generated in a side chain of the resin by irradiation with actinic rays or radiation. Actinic ray or radiation sensitive resin composition.

(8) The resin according to any one of (1) to (7), wherein the resin (P) further has a repeating unit (C) represented by the following general formula (VI): Light or radiation sensitive resin composition.

Here, R ₀₁ , R ₀₂ and R ₀₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl. Represents a group. R ₀₃ represents a substituted or unsubstituted alkylene group, and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n represents an integer of 1 to 4.
(9) The actinic ray-sensitive or radiation-sensitive resin according to any one of (1) to (8), wherein the compound (U) is a resin having a weight average molecular weight of 1000 to 100,000. Composition.

  (10) The actinic ray-sensitive or radiation-sensitive property according to (9), wherein the compound (U) is a resin having a fluorine atom and / or a silicon atom and / or a hydrocarbon group in a side chain. Resin composition.

  (11) The actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (10), further comprising a basic compound.

  (12) The actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (11), wherein an electron beam, X-ray or EUV light is used as an exposure light source.

  (13) A pattern forming method comprising a step of forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (12), exposing and developing.

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

  According to the present invention, a positive that simultaneously satisfies high sensitivity, high resolution, good pattern shape, good line edge roughness, and outgas reduction in an ultrafine region, particularly in electron beam, X-ray or EUV light lithography. Type resist composition, a pattern forming method using the composition, and a resin suitable for the composition can be provided.

¹ HNMR chart of the resin (P-1) of the present invention synthesized in the examples.

Hereinafter, the present invention 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).

<Resin (P)>
The resin (P) contained in the positive resist composition of the present invention is a repeating unit (A) that decomposes upon irradiation with actinic rays or radiation and decomposes by the action of the acid, and is soluble in an aqueous alkali solution. It is resin characterized by having a repeating unit (B) which has a structure which increases.

(1) Repeating unit (A)
As the repeating unit (A), any repeating unit capable of decomposing upon irradiation with actinic rays or radiation to generate an acid can be used.

As said repeating unit (A), the repeating unit represented by either of the following general formula (III)-(V) is preferable, for example.

Here, R ₀₄ , R ₀₅ and R _{07 to} R ₀₉ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group or an alkoxycarbonyl group.
R ₀₆ represents a cyano group, a carboxyl group, —CO—OR ₂₅ or —CO—N (R ₂₆ ) (R ₂₇ ). R ₂₆ and R ₂₇ may combine to form a ring with the nitrogen atom.
X _{1 to} X ₃ are each independently a single bond, an arylene group, an alkylene group, a cycloalkylene group, —O—, —SO ₂ —, —CO—, —N (R ₃₃ ) —, or a combination thereof. Represents a divalent linking group.
R ₂₅ represents an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group or an aralkyl group.
R ₂₆ , R ₂₇ and R ₃₃ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group or an aralkyl group.
A represents a structural site that decomposes upon irradiation with actinic rays or radiation to generate an acid.

In the general formulas (III) to (V), the alkyl groups represented by R _{04 to} R ₀₅ and R _{07 to} R ₀₉ are preferably a methyl group, an ethyl group, a propyl group, or an isopropyl group that may have a substituent. Group, an n-butyl group, a sec-butyl group, a hexyl group, a 2-ethylhexyl group, an octyl group, a dodecyl group and the like, and an alkyl group having 20 or less carbon atoms, and more preferably an alkyl group having 8 or less carbon atoms. .

  Examples of the cycloalkyl group include cycloalkyl groups that may be monocyclic or polycyclic. Preferable examples include a monocyclic cycloalkyl group having 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group which may have a substituent.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is more preferable.

As the alkyl group contained in the alkoxycarbonyl group, the same alkyl groups as those described above for R _{04 to} R ₀₅ and R _{07 to} R ₀₉ are preferable.

As the alkyl group for R _{25 to} R ₂₇ and R ₃₃ , an optionally substituted methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, hexyl group, An alkyl group having 20 or less carbon atoms such as 2-ethylhexyl group, octyl group or dodecyl group is exemplified, and an alkyl group having 8 or less carbon atoms is more preferable.

  Examples of the cycloalkyl group include cycloalkyl groups that may be monocyclic or polycyclic. Preferable examples include a monocyclic cycloalkyl group having 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group which may have a substituent.

  Preferred examples of the alkenyl group include those having 2 to 6 carbon atoms, such as a vinyl group, propenyl group, allyl group, butenyl group, pentenyl group, hexenyl group, and cyclohexenyl group which may have a substituent. It is done.

  As the aryl group, a monocyclic or polycyclic aromatic group having 6 to 14 carbon atoms which may have a substituent is preferable. Specifically, a phenyl group, a tolyl group, a chlorophenyl group, a methoxyphenyl group, A naphthyl group etc. are mentioned. In addition, aryl groups may be bonded to form a multicycle.

  Examples of the aralkyl group include those having 7 to 15 carbon atoms which may have a substituent such as a benzyl group, a phenethyl group, or a cumyl group.

The ring formed by combining R ₂₆ and R ₂₇ together with the nitrogen atom is preferably a ring that forms a 5- to 8-membered ring. Specific examples include pyrrolidine, piperidine, and piperazine.

The arylene group of X _{1 to} X ₃ is preferably an arylene group having 6 to 14 carbon atoms which may have a substituent, and specific examples thereof include a phenylene group, a tolylene group and a naphthylene group.

  The alkylene group is preferably an alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group and an octylene group.

  Preferred examples of the cycloalkylene group include those having 5 to 8 carbon atoms such as a cyclopentylene group and a cyclohexylene group which may have a substituent.

Preferred substituents for each group in the general formulas (III) to (V) include a hydroxyl group, a halogen atom (fluorine, chlorine, bromine, iodine), a nitro group, a cyano group, an amide group, a sulfonamide group, R ₀₄ to R _09, R ₂₅ ~R _27, alkyl groups listed R _33, a methoxy group, an ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, an alkoxy group or a butoxy group, a methoxycarbonyl group, such as ethoxycarbonyl group Examples include an acyl group such as an alkoxycarbonyl group, formyl group, acetyl group and benzoyl group, an acyloxy group such as an acetoxy group and a butyryloxy group, and a carboxy group. The substituent preferably has 8 or less carbon atoms.

  A represents a structural site that decomposes upon irradiation with actinic rays or radiation to produce an acid. Specifically, photoinitiator for photocationic polymerization, photoinitiator for photoradical polymerization, photodecolorant for dyes, light Examples thereof include a structural portion possessed by a compound that generates acid by known light used in a color changing agent or a microresist.

  Examples of the structural site that generates acid upon irradiation with actinic rays or radiation include ionic structural sites possessed by the following photoacid generators.

  Diazonium salts described in S. I. Schlesinger, Photogr. Sci. Eng., 18, 387 (1974), T. S. Bal etal, Polymer, 21, 423 (1980) and the like.

  Ammonium salts described in U.S. Pat. Nos. 4,069,055, 4,069,056, 27,992, and the like.

  DCNecker etal, Macromolecules, 17, 2468 (1984), CSWen et al, Teh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct (1988), U.S. Pat.Nos. 4,069,055, 4,069,056, etc. Phosphonium salt.

  JVCrivello etal, Macromorecules, 10 (6), 1307 (1977), Chem. & Eng.News, Nov. 28, p31 (1988), European Patent No. 104,143, US Patent Nos. 339,049, 410,201, JP Iodonium salts described in, for example, 2-150,848 and JP-A-2-296,514.

  JVCrivello etal, Polymer J. 17, 73 (1985), JVCrivello et.al. J. Org. Chem., 43, 3055 (1978), WRWatt etal, J. Polymer Sci., Polymer Chem. Ed., 22,1789 (1984), JVCrivello et al, Polymer Bull., 14,279 (1985), JVCrivello et al, Macromorecules, 14 (5), 1141 (1981), JVCrivello et al, J. Polymer Sci., Polymer Chem. Ed., 17, 2877 (1979), European Patent Nos. 370,693, 3,902,114, 233,567, 297,443, 297,442, U.S. Patents 4,933,377, 161,811, 410,201, 339,049 No. 4,760,013, No. 4,734,444, No. 2,833,827, Korean Patent Nos. 2,904,626, No. 3,604,580, No. 3,604,581 and the like.

  Selenonium salts described in J.V.Crivello etal, Macromorecules, 10 (6), 1307 (1977), J.V.Crivello etal, J. PolymerSci., Polymer Chem. Ed., 17, 1047 (1979).

Onium salts such as arsonium salts described in C.S. Wen etal, Teh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct (1988).

A is more preferably an ionic structural site containing a sulfonium salt or an iodonium salt. More specifically, A is preferably a group represented by the following general formula (ZI) or (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).

Z ⁻ represents an acid anion generated by decomposition upon irradiation with actinic rays or radiation, and is preferably a non-nucleophilic anion. Examples of the non-nucleophilic anion include a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methyl anion.
A non-nucleophilic anion is an anion that has an extremely low ability to cause a nucleophilic reaction, and is an anion that can suppress degradation over time due to an intramolecular nucleophilic reaction. As a result, the temporal stability of the resin is improved, and the temporal stability of the resist is also improved.

Examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include the corresponding groups in the groups represented by (ZI-1), (ZI-2) and (ZI-3) described later. .
More preferable examples of the group represented by (ZI) include a (ZI-1) group, a (ZI-2) group, and a (ZI-3) group described below.
The (ZI-1) group is a group having arylsulfonium as a cation, in which at least one of R _{201 to} R ₂₀₃ in the general formula (ZI) is an aryl group.

All of R ₂₀₁ to R ₂₀₃ may be an aryl group or a part of R ₂₀₁ to R ₂₀₃ is an aryl group and the remainder may be an alkyl group or a cycloalkyl group.
For example, groups corresponding to triarylsulfonium, diarylalkylsulfonium, aryldialkylsulfonium, diarylcycloalkylsulfonium, aryldicycloalkylsulfonium can be exemplified.

  The aryl group in the arylsulfonium 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 aryl group having a heterocyclic structure include a pyrrole residue (a group formed by losing one hydrogen atom from pyrrole) and a furan residue (a group formed by losing one hydrogen atom from furan). Groups), thiophene residues (groups formed by the loss of one hydrogen atom from thiophene), indole residues (groups formed by the loss of one hydrogen atom from indole), benzofuran residues ( A group formed by losing one hydrogen atom from benzofuran), a benzothiophene residue (a group formed by losing one hydrogen atom from benzothiophene), and the like. When arylsulfonium 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 arylsulfonium 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 or ethyl group. Group, propyl group, n-butyl group, sec-butyl group, t-butyl group, cyclopropyl group, cyclobutyl group, cyclohexyl group and the like.

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 (ZI-2) group will be described.
The (ZI-2) group is a group in which R _{201 to} R ₂₀₃ in the general 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 (ZI-3) group is a group represented by the following general formula (ZI-3), which is a group having a phenacylsulfonium salt structure.

In general formula (ZI-3),
R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or a halogen atom.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
R _x and R _y each independently represents an alkyl group, a cycloalkyl group, 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. Examples of the group formed by combining any two or more of R _{1c to} R _5c , R _6c and R _7c , and R _x and R _y include a butylene group and a pentylene group.
Zc ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as Z ^{− in} formula (ZI).

The alkyl group as R _{1c to} R _7c may be either linear or branched, for example, an alkyl group having 1 to 20 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms ( Examples thereof include a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, and a linear or branched pentyl group. Examples of the cycloalkyl group include cyclohexane having 3 to 8 carbon atoms. An alkyl group (for example, a cyclopentyl group, a cyclohexyl group) can be mentioned.

The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).

Preferably, any of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _{1c to} R _5c. Is 2-15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group and cycloalkyl group as R _x and R _y include the same alkyl group and cycloalkyl group as in R _{1c to} R _7c , such as a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxy group. A carbonylmethyl group is more preferred.

Examples of the 2-oxoalkyl group and 2-oxocycloalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .
Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as in R _{1c to} R _5c .

R _x and R _y are preferably an alkyl group or cycloalkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more alkyl groups or cycloalkyl groups.

In the general formula (ZII), R ₂₀₄ ~R ₂₀₅ each independently represents an aryl group, an alkyl group or a cycloalkyl group.
The aryl group for R ₂₀₄ and R ₂₀₅ is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. Aryl group R ₂₀₄ to R ₂₀₅ represents an oxygen atom, a nitrogen atom, may be an aryl group having a heterocyclic structure having a sulfur atom and the like. Examples of the aryl group having a heterocyclic structure include a pyrrole residue (a group formed by losing one hydrogen atom from pyrrole) and a furan residue (a group formed by losing one hydrogen atom from furan). Groups), thiophene residues (groups formed by the loss of one hydrogen atom from thiophene), indole residues (groups formed by the loss of one hydrogen atom from indole), benzofuran residues ( A group formed by losing one hydrogen atom from benzofuran), a benzothiophene residue (a group formed by losing one hydrogen atom from benzothiophene), and the like.

The alkyl group and cycloalkyl group in R ₂₀₄ and R ₂₀₅ are preferably a linear or branched alkyl group having 1 to 10 carbon atoms (for example, 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).

The aryl group, alkyl group, and cycloalkyl group of R ₂₀₄ and R ₂₀₅ may have a substituent. Aryl groups R _204, R _205, an alkyl group, the cycloalkyl group substituent which may be possessed by, for example, 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, having 6 to 15 carbon atoms), an alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group.
Z ⁻ represents an acid anion generated by decomposition upon irradiation with actinic rays or radiation, and is preferably a non-nucleophilic anion, and examples thereof include the same as Z ⁻ in the general formula (ZI).

As A, the group represented by the following general formula (ZCI) or (ZCII) is also mentioned as a preferred example.

In the above general formula (ZCI),
R ₃₀₁ and R ₃₀₂ each independently represents an organic group.
Carbon number of the organic group as R ₃₀₁ and R ₃₀₂ is generally 1 to 30, preferably 1 to 20.

R _{301 to} R ₃₀₂ 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. Examples of the group formed by bonding include an alkylene group (for example, a butylene group and a pentylene group).
Specific examples of the organic group for R ₃₀₁ and R ₃₀₂ include an aryl group, an alkyl group, a cycloalkyl group, and the like given as examples of R _{201 to} R ₂₀₃ in the general formula (ZI).

  M represents an atomic group which a proton gives to form an acid. More specifically, it is a structure represented by general formulas AN1 to AN4 described later, and among these, the structure represented by AN1 is preferable.

R ₃₀₃ represents an organic group. The organic group as R ₃₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms. Specific examples of the organic group for R ₃₀₃ include an aryl group, an alkyl group, a cycloalkyl group, and the like given as specific examples of R ₂₀₄ and R ₂₀₅ in the general formula (ZII).

  Moreover, as a structural site | part which generate | occur | produces an acid by irradiation of actinic light or a radiation, the structural site | part used as the sulfonic acid precursor which the following photoacid generator has can be mentioned, for example.

  For example, M.TUNOOKA etal, Polymer Preprints Japan, 35 (8), G. Berner etal, J. Rad.Curing, 13 (4), WJMijs etal, Coating Technol., 55 (697), 45 (1983), Akzo, H. Adachietal, Polymer Preprints, Japan, 37 (3), European Patent Nos. 0199,672, 84515, 199,672, 044,115, 0101,122, U.S. Patents 618,564, 4,371,605 No. 4,431,774, JP-A-64-18143, JP-A-2-245756, JP-A-4-365048, and other publications such as iminosulfonates. A compound that generates sulfonic acid.

Disulfone compounds described in JP-A No. 61-166544.
Furthermore, VNRPillai, Synthesis, (1), 1 (1980), A. Abad etal, Tetrahedron Lett., (47) 4555 (1971), DHR Barton etal, J. Chem. Soc., (C), 329 (1970) US Pat. No. 3,779,778, European Patent No. 126,712, and the like.

  The repeating unit (A) is more preferably a structure that generates an acid anion in the side chain of the resin by irradiation with actinic rays or radiation. When such a structure is selected, diffusion of the generated acid anion is suppressed, which is effective from the viewpoint of improving the resolution and improving the line edge roughness.

Although the preferable specific example of A is given below, it is not specifically limited to these.

As the repeating unit represented by any one of the general formulas (III) to (V) effectively used in the present invention, more preferably, the following general formulas (III-1) to (III-6), What is represented by either (IV-1)-(IV-4) and general formula (V-1)-(V-2) can be mentioned.

In the general formula, Ar _1a represents an arylene group which may have a substituent similar to the arylene group represented by X _{1 to} X ₃ in the general formulas (III) to (V).
Ar _{2 a to} Ar _{4 a} may have a substituent similar to the aryl groups represented by R _{201 to} R ₂₀₃ and R _{204 to} R ₂₀₅ in the general formulas (ZI) and (ZII). Represents an aryl group.
R ₀₁ represents a hydrogen atom, a methyl group, a chloromethyl group, a trifluoromethyl group, or a cyano group.

R ₀₂ and R ₀₂₁ are the same as those represented by X _{1 to} X ₃ , such as a single bond, an arylene group, an alkylene group, a cycloalkylene group, —O—, —SO ₂ —, CO—, —N (R ₃₃ )-Or a divalent linking group in which a plurality of these are combined.

R ₀₃ and R ₀₁₉ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. Examples of the alkyl group and cycloalkyl group include the same alkyl groups and cycloalkyl groups as R _{01 to} R ₀₃ in the general formula (I) described later. As an aryl group and an aralkyl group, the same thing as the aryl group and aralkyl group as L < ₁ > -L < ₂ > in postscript general formula (II) can be mentioned.

Preferred examples of the repeating unit represented by any one of the general formulas (III) to (V) include those represented by the following general formulas (I-7) to (I-34).

In the formula, Ar _1, Ar ₅ is the same as X ₁ to X ₃ in the above represents an optionally substituted arylene group. Ar _{2 to} Ar ₃ and Ar _{6 to} Ar ₇ represent an aryl group which may have a substituent, similar to the aryl groups represented by R _{25 to} R ₂₇ and R ₃₃ described above. R ₀₁ represents a hydrogen atom, a methyl group, a chloromethyl group or a cyano group.

R ₀₂ represents the same arylene group, alkylene group or cycloalkylene group as X _{1 to} X ₃ . R ₀₃ , R _{05 to} R ₀₁₀ , R ₀₁₃ and R _{015 each} represents an alkyl group, a haloalkyl group, a cycloalkyl group, an aryl group or an aralkyl group. R ₀₄ represents an arylene group which may have a substituent, an alkylene group, or an alkenylene group having 2 to 6 carbon atoms which may have a substituent. As the alkenyl group, an alkenylene group having 2 to 6 carbon atoms such as an ethylene group, a propenylene group, and a butenylene group which may have a substituent is preferable.

R ₀₁₁ and R ₀₁₄ represent a hydroxyl group, a halogen atom (fluorine, chlorine, bromine, iodine), and an alkyl group, an alkoxy group, an alkoxycarbonyl group, and an acyloxy group shown as preferred further substituents as described above. R ₀₁₂ represents a nitro group, a cyano group, or a perfluoroalkyl group such as a trifluoromethyl group or a pentafluoroethyl group. X ⁻ represents an anion of aryl sulfonic acid, heteroaryl sulfonic acid, alkyl sulfonic acid, cycloalkyl sulfonic acid, or perfluoroalkyl sulfonic acid.

  The content of the repeating unit (A) in the resin (P) of the present invention is preferably in the range of 0.5 to 80 mol%, and in the range of 1 to 60 mol%, based on all repeating units. It is more preferable to contain, and it is especially preferable to contain in 3-40 mol%.

  A method for synthesizing the monomer corresponding to the repeating unit (A) is not particularly limited. For example, the acid anion having a polymerizable unsaturated bond corresponding to the repeating unit and a known onium salt halide are exchanged. A method is mentioned.

  More specifically, a metal ion salt (for example, sodium ion, potassium ion, etc.) or an ammonium salt (ammonium, triethylammonium salt, etc.) of an acid having a polymerizable unsaturated bond corresponding to the repeating unit, and a halogen ion ( An onium salt having a chloride ion, bromide ion, iodide ion, etc.) is stirred in the presence of water or methanol to carry out an anion exchange reaction, such as dichloromethane, chloroform, ethyl acetate, methyl isobutyl ketone, tetrahydroxyfuran, etc. By performing a liquid separation / washing operation with an organic solvent and water, a monomer corresponding to the desired repeating unit (A) can be synthesized.

  After anion exchange reaction by stirring in the presence of an organic solvent that can be separated from water, such as dichloromethane, chloroform, ethyl acetate, methyl isobutyl ketone, and tetrahydroxyfuran, and water separation, washing with water It can also be synthesized by operating.

Specific examples of the repeating unit represented by any one of the general formulas (III) to (V) are shown below, but the present invention is not limited thereto.

(2) Repeating unit (B)
As the repeating unit (B) contained in the resin (P), any repeating unit having a structure that is decomposed by the action of an acid and increases the solubility in an alkaline aqueous solution can be used.

Examples of the structure that is decomposed by the action of an acid and increases the solubility in an aqueous alkali solution include groups represented by -COOA ⁰ and -O-B ⁰ groups. Further Examples of the group containing these, include groups represented by -R ⁰ -COOA ^0, or -Ar-O-B ^0. Here, A ⁰ is -C (R ⁰¹ ) (R ⁰² ) (R ⁰³ ), -Si (R ⁰¹ ) (R ⁰² ) (R ⁰³ ) or -C (R ⁰⁴ ) (R ⁰⁵ ) -O-R ⁰⁶ groups are shown. B ⁰ represents an A ⁰ or —CO—O—A ⁰ group. R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R ⁰⁵ are the same or different and each represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group or an aryl group, and R ⁰⁶ represents an alkyl group or an aryl group. However, at least two of R ^{01 to} R ⁰³ are groups other than hydrogen atoms, and two groups of R ^{01 to} R ⁰³ and R ^{04 to} R ⁰⁶ may be bonded to form a ring. Good. R ⁰ represents a divalent aliphatic or aromatic hydrocarbon group which may have a substituent, and —Ar— represents a divalent aromatic which may have a monocyclic or polycyclic substituent. Indicates a group.

  The repeating unit (B) is preferably a repeating unit having a group in which a hydrogen atom of a phenolic hydroxyl group is substituted with a group capable of leaving by the action of an acid.

As the repeating unit (B), for example, a repeating structural unit represented by the following general formula (I) is preferable.

Here, R ₀₁ , R ₀₂ and R ₀₃ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group or an alkoxycarbonyl group. R ₀₃ represents an alkylene group and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.

Ar ₁ represents an aromatic ring group.

  n Y's each independently represent a hydrogen atom or a group capable of leaving by the action of an acid. However, at least one of Y represents a group capable of leaving by the action of an acid.

  n represents an integer of 1 to 4.

The alkyl group represented by R _{01 to} R ₀₃ in the general formula is preferably a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, hexyl group, which may have a substituent, An alkyl group having 20 or less carbon atoms such as 2-ethylhexyl group, octyl group or dodecyl group is exemplified, and an alkyl group having 8 or less carbon atoms is more preferable.

The alkyl group contained in the alkoxycarbonyl group is preferably the same as the alkyl group in R _{01 to} R ₀₃ .

  Examples of the cycloalkyl group include cycloalkyl groups that may be monocyclic or polycyclic. Preferable examples include a monocyclic cycloalkyl group having 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group which may have a substituent.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is more preferable.

When R ₀₃ represents an alkylene group, the alkylene group is preferably an alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, and an octylene group.

The aromatic ring group of Ar ₁ preferably has 6 to 14 carbon atoms which may have a substituent, and specific examples thereof include a benzene ring, a toluene ring, a naphthalene ring and the like.

  n Y's each independently represent a hydrogen atom or a group capable of leaving by the action of an acid. However, at least one of n represents a group capable of leaving by the action of an acid.

Examples of the group Y leaving by the action of an acid include —C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), —C (═O) —O—C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ). ), -C (R ₀₁ ) (R ₀₂ ) (OR ₃₉ ), -C (R ₂₁ ) (R ₂₂ ) -C (= O) -O-C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), —CH (R ₃₆ ) (Ar) and the like can be mentioned.

In the formula, R _{36 to} R ₃₉ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be bonded to each other to form a ring.
R _{21 to} R ₂₂ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.

  Ar represents an aryl group.

The alkyl group of R _{36 to} R ₃₉ , R ₂₁ and R ₂₂ is preferably an alkyl group having 1 to 8 carbon atoms, for example, methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, hexyl. Group, octyl group and the like.

The cycloalkyl group of R _{36 to} R ₃₉ , R ₀₁ and R ₀₂ may be monocyclic or polycyclic. The monocyclic type is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. As the polycyclic type, a cycloalkyl group having 6 to 20 carbon atoms is preferable. For example, an adamantyl group, norbornyl group, isobornyl group, camphanyl group, dicyclopentyl group, α-pinel group, tricyclodecanyl group, tetracyclododecyl group. Group, androstanyl group and the like. A part of carbon atoms in the cycloalkyl group may be substituted with a hetero atom such as an oxygen atom.

The aryl group of R _{36 to} R ₃₉ , R ₂₁ , R ₂₂ and Ar is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group.
The aralkyl group of R _{36 to} R ₃₉ , R ₂₁ and R ₂₂ is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.
The alkenyl group of R _{36 to} R ₃₉ , R ₀₁ and R ₀₂ is preferably an alkenyl group having 2 to 8 carbon atoms, and examples thereof include a vinyl group, an allyl group, a butenyl group, and a cyclohexenyl group.

The ring formed by combining R ₃₆ and R ₃₇ with each other may be monocyclic or polycyclic. The monocyclic type is preferably a cycloalkane structure having 3 to 8 carbon atoms, and examples thereof include a cyclopropane structure, a cyclobutane structure, a cyclopentane structure, a cyclohexane structure, a cycloheptane structure, and a cyclooctane structure. As the polycyclic type, a cycloalkane structure having 6 to 20 carbon atoms is preferable, and examples thereof include an adamantane structure, a norbornane structure, a dicyclopentane structure, a tricyclodecane structure, and a tetracyclododecane structure. A part of carbon atoms in the cycloalkane structure may be substituted with a hetero atom such as an oxygen atom.

Each of the above groups as R _{36 to} R ₃₉ , R ₀₁ , R ₀₂ , R _03, R ₂₁ , R ₂₂ , Ar and Ar ₁ may have a substituent. Group, cycloalkyl group, aryl group, amino group, amide group, ureido group, urethane group, hydroxyl group, carboxyl group, halogen atom, alkoxy group, thioether group, acyl group, acyloxy group, alkoxycarbonyl group, cyano group, nitro Group and the like, and a substituent having 8 or less carbon atoms is preferable.

The group Y that is eliminated by the action of an acid is more preferably a structure represented by the following general formula (II).

Here, L ₁ and L ₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group.
M represents a single bond or a divalent linking group.
Q represents an alkyl group, a cycloalkyl group, an alicyclic group which may contain a hetero atom, an aromatic ring group which may contain a hetero atom, an amino group, an ammonium group, a mercapto group, a cyano group or an aldehyde group. .
At least two of Q, M, and L ₁ may combine to form a 5-membered or 6-membered ring.

The alkyl group as L ₁ and L ₂ is, for example, an alkyl group having 1 to 8 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group. An octyl group can be preferably mentioned.
The cycloalkyl group as L ₁ and L ₂ is, for example, a cycloalkyl group having 3 to 15 carbon atoms, and specifically, a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group can be preferably exemplified.
The aryl group as L ₁ and L ₂ is, for example, an aryl group having 6 to 15 carbon atoms, and specific examples thereof include a phenyl group, a tolyl group, a naphthyl group, and an anthryl group.
The aralkyl group as L ₁ and L ₂ has, for example, 6 to 20 carbon atoms, and examples thereof include a benzyl group and a phenethyl group.

The divalent linking group as M is, for example, an alkylene group (for example, methylene group, ethylene group, propylene group, butylene group, hexylene group, octylene group, etc.), cycloalkylene group (for example, cyclopentylene group, cyclohexylene group). Group), alkenylene group (for example, ethylene group, propenylene group, butenylene group, etc.), arylene group (for example, phenylene group, tolylene group, naphthylene group, etc.), -S-, -O-, -CO-, -SO _2- , -N (R ₀ )-, and a divalent linking group in which a plurality of these are combined. R ₀ represents a hydrogen atom or an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms, specifically a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group). Octyl group, etc.).

The alkyl group and cycloalkyl group as Q are the same as the above groups as L ₁ and L ₂ .
As the alicyclic group and the aromatic ring group in the alicyclic group which may contain a hetero atom as Q and the aromatic ring group which may contain a hetero atom, the cycloalkyl as L ₁ and L ₂ described above is used. Group, an aryl group, etc. are mentioned, Preferably it is C3-C15.
Examples of the alicyclic group containing a hetero atom and the aromatic ring group containing a hetero atom include, for example, thiirane, cyclothiolane, thiophene, furan, pyrrole, benzothiophene, benzofuran, benzopyrrole, triazine, imidazole, benzimidazole, triazole, thiadiazole, thiazole. And groups having a heterocyclic structure such as pyrrolidone, but are not limited to these as long as the structure is generally called a heterocyclic ring (a ring formed of carbon and a heteroatom, or a ring formed of a heteroatom). .

As a 5-membered or 6-membered ring that may be formed by combining at least two of Q, M, and L ₁ , at least two of Q, M, and L ₁ are combined to form, for example, a propylene group and a butylene group In this case, a 5-membered or 6-membered ring containing an oxygen atom is formed.
Each group represented by L ₁ , L ₂ , M, and Q in the general formula (II) may have a substituent. For example, R _{36 to} R ₃₉ , R ₀₁ , R ₀₂ , _{Examples of the} substituent that may be possessed by R _03, Ar and Ar ₁ are mentioned, and the substituent preferably has 8 or less carbon atoms.

The group represented by -MQ is preferably a group composed of 1 to 30 carbon atoms, more preferably a group composed of 5 to 20 carbon atoms.
Specific examples of the repeating unit represented by the general formula (I) are shown below, but are not limited thereto.

The content of the repeating unit (B) in the resin (P) of the present invention is preferably 3 to 90 mol%, preferably 5 to 80 mol%, based on all repeating units. It is more preferable, and it is especially preferable to contain in the range of 7-70 mol%.
The ratio of the repeating unit (A) to the repeating unit (B) in the resin (P) (number of moles of A / number of moles of B) is preferably 0.04 to 1.0, and 0.05 to 0.9. Is more preferable, and 0.06 to 0.8 is particularly preferable.

(3) Repeating unit (C)
The resin in the present invention preferably further has a repeating unit (C) represented by the following general formula (VI).

Here, R ₀₁ , R ₀₂ and R ₀₃ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group or an alkoxycarbonyl group. R ₀₃ represents an alkylene group and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n represents an integer of 1 to 4.

In the general formula _{(VI), R 01, R} 02, R 03, and specific examples of Ar ₁ are in the general formula _{(I), R 01, R} 02, R 03, and similarly to the Ar ₁ belongs to.
Specific examples of the repeating unit represented by the general formula (VI) are shown below, but are not limited thereto.

  The content of the repeating unit (C) in the resin of the present invention is preferably 3 to 90 mol%, more preferably 5 to 80 mol%, based on all repeating units. Preferably, it is contained in the range of 7 to 70 mol%.

(4) Form of Resin (P) of the Present Invention, Polymerization Method, Molecular Weight, etc. The form of the resin (P) may be any of random type, block type, comb type, and star type.
The resin (P) according to the present invention containing the above repeating units (A) and (B), or the resin (P) according to the present invention containing the repeating units (A), (B) and (C), For example, it can be synthesized by radical, cation, or anionic polymerization of unsaturated monomers corresponding to each structure. It is also possible to obtain the desired resin by conducting a polymer reaction after polymerization using an unsaturated monomer corresponding to the precursor of each structure.

  The resin (P) according to the present invention has 0.5 to 80 mol% of the repeating unit (A), 3 to 90 mol% of the repeating unit (B), and 3 to 90 mol% of the repeating unit (C). preferable.

The molecular weight of the resin (P) according to the present invention is not particularly limited, but the weight average molecular weight is preferably in the range of 1000 to 100,000, more preferably in the range of 1500 to 70000, and in the range of 2000 to 50000. It is particularly preferred. Here, the weight average molecular weight of the resin indicates a molecular weight in terms of polystyrene measured by GPC (carrier: THF or N-methyl-2-pyrrolidone (NMP)).
The dispersity (Mw / Mn) is preferably 1.00 to 5.00, more preferably 1.03 to 3.50, and still more preferably 1.05 to 2.50.

Further, for the purpose of improving the performance of the resin according to the present invention, it may further have a repeating unit derived from another polymerizable monomer as long as the dry etching resistance is not significantly impaired.
The content of repeating units derived from other polymerizable monomers in the resin is generally 50 mol% or less, preferably 30 mol% or less, based on all repeating units. Other polymerizable monomers that can be used include those shown below. For example, it is a compound having one addition polymerizable unsaturated bond selected from (meth) acrylic acid esters, (meth) acrylamides, allyl compounds, vinyl ethers, vinyl esters, styrenes, crotonic acid esters and the like. .

  Specifically, (meth) acrylic acid esters include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, t-butyl (meth) acrylate, (meth) Amyl acrylate, cyclohexyl (meth) acrylate, ethylhexyl (meth) acrylate, octyl (meth) acrylate, (meth) acrylic acid-t-octyl, (meth) acrylic acid 2-chloroethyl, (meth) acrylic acid 2 -Hydroxyethyl, glycidyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate and the like.

  (Meth) acrylamides include, for example, (meth) acrylamide, N-alkyl (meth) acrylamide, (the alkyl group has 1 to 10 carbon atoms, for example, methyl group, ethyl group, propyl group, butyl Group, t-butyl group, heptyl group, octyl group, cyclohexyl group, benzyl group, hydroxyethyl group, benzyl group, etc.), N-aryl (meth) acrylamide (as aryl groups, for example, phenyl group, tolyl group , Nitrophenyl group, naphthyl group, cyanophenyl group, hydroxyphenyl group, carboxyphenyl group, etc.), N, N-dialkyl (meth) acrylamide (the alkyl group has 1 to 10 carbon atoms, for example, , Methyl group, ethyl group, butyl group, isobutyl group, ethylhexyl group, Hexyl group, etc.), N, N-aryl (meth) acrylamide (aryl groups include, for example, phenyl group), N-methyl-N-phenylacrylamide, N-hydroxyethyl-N-methylacrylamide. N-2-acetamidoethyl-N-acetylacrylamide and the like.

  Examples of allyl compounds include allyl esters (eg, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate), allyl Examples include oxyethanol.

  Examples of vinyl ethers include alkyl vinyl ethers (for example, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethyl hexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2- Ethyl butyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether, etc., vinyl aryl ethers (eg vinyl phenyl ether, vinyl tolyl ether, vinyl chloride) Phenyl ether, vinyl 2,4-dichlorophenyl ether, vinyl naphthyl ether, vinyl anthranyl ether) and the like.

  Examples of vinyl esters include vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxyacetate, vinyl butoxyacetate, Examples thereof include vinyl phenyl acetate, vinyl acetoacetate, vinyl lactate, vinyl-β-phenyl butyrate, vinyl cyclohexyl carboxylate, vinyl benzoate, vinyl salicylate, vinyl chlorobenzoate, vinyl tetrachlorobenzoate, vinyl naphthoate and the like.

  Examples of styrenes include styrene and alkyl styrene (for example, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, isopropyl styrene, butyl styrene, hexyl styrene, cyclohexyl styrene, decyl styrene, benzyl styrene, chloromethyl styrene). , Trifluoromethyl styrene, ethoxymethyl styrene, acetoxymethyl styrene, etc.), alkoxy styrene (eg, methoxy styrene, 4-methoxy-3-methyl styrene, dimethoxy styrene, etc.), alkylcarbonyloxy styrene (eg, 4-acetoxy styrene, 4-cyclohexylcarbonyloxystyrene), arylcarbonyloxystyrene (for example, 4-phenylcarbonyloxystyrene) ), Halogen styrene (for example, chlorostyrene, dichlorostyrene, trichlorostyrene, tetrachlorostyrene, pentachlorostyrene, bromostyrene, dibromostyrene, iodostyrene, fluorostyrene, trifluorostyrene, 2-bromo-4-trifluoro) Rumethylstyrene, 4-fluoro-3-trifluoromethylstyrene, etc.), cyanostyrene, carboxystyrene and the like.

  Examples of the crotonic acid esters include alkyl crotonic acid (for example, butyl crotonic acid, hexyl crotonic acid, glycerin monocrotonate, etc.).

Examples of the dialkyl itaconates include dimethyl itaconate, diethyl itaconate, and dibutyl itaconate.
Examples of the dialkyl esters of maleic acid or fumaric acid include dimethyl maleate and dibutyl fumarate.
In addition, maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, maleilonitrile, and the like can be given. In general, any addition-polymerizable unsaturated compound copolymerizable with the repeating unit according to the present invention can be used without any particular limitation.

  Resin (P) of this invention can be used individually by 1 type or in combination of 2 or more types. The content of the resin (P) is preferably 30 to 99.9% by mass, more preferably 50 to 99% by mass, and 70 to 98% by mass based on the total solid content in the positive resist composition of the present invention. % Is particularly preferred.

Although the specific example of resin (P) is given below, it is not limited to these.
Specific examples of the resin (P) include, for example, one or more repeating units selected from the specific examples of the general formulas (III) to (IV) / 1 selected from the specific examples of the general formula (I). Resin having one or more kinds of repeating units, one or more kinds of repeating units selected from the specific examples of the general formulas (III) to (IV) / one or more kinds of selected from the specific examples of the general formula (I) Repeating unit / resin having one or more repeating units selected from the specific examples of the general formula (VI).
More preferable specific examples include resins having the following structure.

<Compound (U) unevenly distributed on the film surface and forming a protective layer>
In the present invention, the compound (U) that is unevenly distributed on the film surface refers to a compound that can form a protective layer unevenly on the resist film surface by being added to the resist composition. Whether or not the protective layer is formed is determined by, for example, determining the surface static contact angle (contact angle with pure water) of the resist film to which the compound (U) is not added and the surface static contact angle of the resist film to which the compound (U) is added. In comparison, when the contact angle increases, it can be considered that a protective layer has been formed.

  The compound (U) is ubiquitous at the interface as described above, but unlike the surfactant, it does not necessarily have a hydrophilic group in the molecule, and the polar / nonpolar substance is mixed uniformly. You don't have to contribute to

  The compound (U) is not particularly limited as long as the above properties are satisfied, but is preferably a resin, and particularly preferably a resin having a weight average molecular weight in the range of 1000 to 100,000 (hereinafter referred to as compound ( When U) is a resin, it is also expressed as a compound (U ′)).

  Further, from the viewpoint of uneven distribution on the film surface, the compound (U ′) has (i) a fluorine atom in the main chain or side chain of the resin, (ii) a silicon atom in the main chain or side chain of the resin, Or (iii) It preferably has at least one feature of having a hydrocarbon group in the side chain of the resin.

When the compound (U ′) has a fluorine atom in the main chain or side chain of the resin (i), as the partial structure having a fluorine atom, an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or a fluorine atom It is preferable that it is resin which has an aryl group which has.
The alkyl group having a fluorine atom (preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms) is a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, It may have a substituent.

The cycloalkyl group having a fluorine atom is a monocyclic or polycyclic cycloalkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and may further have another substituent.
Examples of the aryl group having a fluorine atom include those in which at least one hydrogen atom of an aryl group such as a phenyl group or a naphthyl group is substituted with a fluorine atom, and may further have another substituent.

Preferred examples of the alkyl group having a fluorine atom, the cycloalkyl group having a fluorine atom, or the aryl group having a fluorine atom include groups represented by the following general formulas (F2) to (F4). The present invention is not limited to this.

In general formulas (F2) to (F4),
R _{57 to} R ₆₈ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _{57 to} R ₆₁ , R _{62 to} R ₆₄ and R _{65 to} R ₆₈ is a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom (preferably having a carbon number of 1 ~ 4). R _{57 to} R ₆₁ and R _{65 to} R ₆₇ are preferably all fluorine atoms. R ₆₂ , R ₆₃ and R ₆₈ are preferably an alkyl group (preferably having 1 to 4 carbon atoms) in which at least one hydrogen atom is substituted with a fluorine atom, and preferably a perfluoroalkyl group having 1 to 4 carbon atoms. Further preferred. R ₆₂ and R ₆₃ may be connected to each other to form a ring.

Specific examples of the group represented by the general formula (F2) include a p-fluorophenyl group, a pentafluorophenyl group, and a 3,5-di (trifluoromethyl) phenyl group.
Specific examples of the group represented by the general formula (F3) include trifluoromethyl group, pentafluoropropyl group, pentafluoroethyl group, heptafluorobutyl group, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2 -Methyl) isopropyl group, nonafluorobutyl group, octafluoroisobutyl group, nonafluorohexyl group, nonafluoro-t-butyl group, perfluoroisopentyl group, perfluorooctyl group, perfluoro (trimethyl) hexyl group, 2,2 1,3,3-tetrafluorocyclobutyl group, perfluorocyclohexyl group and the like. Hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2-methyl) isopropyl group, octafluoroisobutyl group, nonafluoro-t-butyl group and perfluoroisopentyl group are preferable, and hexafluoroisopropyl group and heptafluoroisopropyl group are preferable. Further preferred.

Specific examples of the group represented by the general formula (F4) include, for example, —C (CF ₃ ) ₂ OH, —C (C ₂ F ₅ ) ₂ OH, —C (CF ₃ ) (CH ₃ ) OH, -CH (CF ₃₎ OH and the like, -C (CF _{3) 2} OH is preferred.

Preferred examples of the repeating unit having a fluorine atom include those shown below.

In the formula, R ₁₀ and R ₁₁ are each independently a hydrogen atom, a fluorine atom, or an alkyl group (preferably a linear or branched alkyl group having 1 to 4 carbon atoms, and particularly as an alkyl group having a substituent, Fluorinated alkyl group can be mentioned).
W _{3 to} W ₆ each independently represents an organic group containing at least one fluorine atom. Specific examples include the atomic groups (F2) to (F4).
Besides these, resins having units as shown below are also applicable.

In the formula, R _{4 to} R ₇ are each independently a hydrogen atom, a fluorine atom, or an alkyl group (preferably a linear or branched alkyl group having 1 to 4 carbon atoms, and the alkyl group having a substituent is In particular, a fluorinated alkyl group can be mentioned).
However, at least one of R _{4 to} R ₇ represents a fluorine atom. R ₄ and R ₅ or R ₆ and R ₇ may form a ring.
W ₂ each independently represents an organic group containing at least one fluorine atom. Specific examples include the atomic groups (F2) to (F4).

L ₂ represents a single bond or a divalent linking group. Examples of the divalent linking group include a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, —O—, —SO ₂ —, —CO—, —N (R )-Or a divalent linking group in which a plurality of these are combined.

Hereinafter, although the specific example of the repeating unit which has a fluorine atom is shown, this invention is not limited to this. In specific examples, X ₁ represents a hydrogen atom, —CH ₃ , —F or —CF ₃ . X ₂ represents —F or —CF ₃ .

When the compound (U ′) has a silicon atom in the main chain or side chain of the resin (ii), a resin having an alkylsilyl structure (preferably a trialkylsilyl group) or a cyclic siloxane structure as a partial structure having a silicon atom It is preferable that
Specific examples of the alkylsilyl structure or the cyclic siloxane structure include groups represented by the following general formulas (CS-1) to (CS-3).

In general formulas (CS-1) to (CS-3),
R _{12 to} R ₂₆ each independently represents a linear or branched alkyl group (preferably having 1 to 20 carbon atoms) or a cycloalkyl group (preferably having 3 to 20 carbon atoms).
L < ₃ > -L < ₅ > represents a single bond or a bivalent coupling group. As the divalent linking group, an alkylene group, a phenylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a urethane group, or a urea group is used alone or in combination of two or more groups. A combination is mentioned.

  n represents an integer of 1 to 5.

Examples of the repeating unit having a silicon atom include the repeating units shown in the above (C-Ia) to (C-Id) and (C-III). (However, W _{3 to} W ₆ are represented as “an atomic group containing at least one silicon atom, specifically, an atomic group represented by (CS-1) to (CS-3)”) To read)
Hereinafter, although the specific example of the repeating unit which has group represented by general formula (CS-1)-(CS-3) is given, this invention is not limited to this. In specific examples, X ₁ represents a hydrogen atom, —CH ₃ , —F or —CF ₃ .

When the compound (U ′) has a hydrocarbon group in the side chain of (iii) resin, it preferably has a hydrocarbon group having 4 or more carbon atoms in the side chain, and a hydrocarbon group having 6 or more carbon atoms in the side chain. More preferably, it has.
Further, in another aspect, preferably has a hydrocarbon group having a -CH ₃ structure at one or more side chains, and more preferably has a hydrocarbon group having a -CH ₃ structure two or more side chains. In this respect, the hydrocarbon group is preferably a branched alkyl group.
Specific examples of the repeating unit include the repeating units represented by the general formulas (C-Ia) to (C-Id). (However, W _{3 to} W ₆ are read as “represents a hydrocarbon group”)
Examples of the side chain hydrocarbon group include an alkyl group, an alkyloxy group, an alkyl-substituted cycloalkyl group, an alkenyl group, an alkyl-substituted alkenyl group, an alkyl-substituted cycloalkenyl group, an alkyl-substituted aryl group, and an alkyl-substituted aralkyl group. Group, an alkyl-substituted cycloalkyl group is preferred.

  As the alkyl group, a linear alkyl group having 1 to 20 carbon atoms or a branched alkyl group having 3 to 20 carbon atoms is preferable. Specific examples of preferable branched alkyl groups include isopropyl, isobutyl, t-butyl, 3-pentyl, 2-methyl-3-butyl, 3-hexyl, and 2-methyl-3-pentyl. 3-methyl-4-hexyl group, 3,5-dimethyl-4-pentyl group, isooctyl group, 2,4,4-trimethylpentyl group, 2-ethylhexyl group, 2,6-dimethylheptyl group, 1,5 -Dimethyl-3-heptyl group, 2,3,5,7-tetramethyl-4-heptyl group and the like. More preferably, an isobutyl group, a t-butyl group, a 2-methyl-3-butyl group, a 2-methyl-3-pentyl group, a 3-methyl-4-hexyl group, a 3,5-dimethyl-4-pentyl group, 2,4,4-trimethylpentyl group, 2-ethylhexyl group, 2,6-dimethylheptyl group, 1,5-dimethyl-3-heptyl group, 2,3,5,7-tetramethyl-4-heptyl group is there.

  Specific examples of preferable linear alkyl groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and nonyl groups.

  Examples of the alkyloxy group include a group in which an ether group is bonded to the above-described alkyl group.

  The cycloalkyl group may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. Preferred cycloalkyl groups include adamantyl group, noradamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, A cyclodecanyl group and a cyclododecanyl group can be mentioned. More preferable examples include an adamantyl group, norbornyl group, cyclohexyl group, cyclopentyl group, tetracyclododecanyl group, and tricyclodecanyl group. More preferably, they are a norbornyl group, a cyclopentyl group, and a cyclohexyl group.

  The cycloalkyl group may be substituted with an alkyl group, and examples thereof include 3,5-dimethylcyclohexyl group, 4-isopropylcyclohexyl group, 4-tbutylcyclohexyl group and the like.

  As the alkenyl group, a linear or branched alkenyl group having 1 to 20 carbon atoms is preferable, and a branched alkenyl group is more preferable.

  The aryl group is preferably an aryl group having 6 to 20 carbon atoms, and examples thereof include a phenyl group and a naphthyl group, and a phenyl group is preferable.

  The aralkyl group is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.

(iii) Preferred specific examples of the repeating unit having a hydrocarbon group in the side chain of the resin are given below. In addition, this invention is not limited to these. In specific examples, Rx represents a hydrogen atom or a methyl group, and Rxa to Rxc each represents an alkyl group having 1 to 4 carbon atoms.

  The total content of the repeating units having the characteristics of any one of (i) to (iii) is preferably 50 to 100 mol%, more preferably 80 to 100 mol%, based on all repeating units in the compound (U ′). More preferably, it is 90-100 mol%.

  The compound (U ′) may further have at least one group selected from the following groups (x) to (z).

(X) an alkali-soluble group,
(Y) a group that decomposes by the action of an alkali developer and increases the solubility in the alkali developer;
(Z) A group that decomposes by the action of an acid.

  (X) Alkali-soluble groups include phenolic hydroxyl groups, carboxylic acid groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, (alkylsulfonyl) ( Alkylcarbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) ) And a methylene group.

  Preferred alkali-soluble groups include fluorinated alcohol groups (preferably hexafluoroisopropanol), sulfonimide groups, and bis (carbonyl) methylene groups.

  Examples of the repeating unit having an alkali-soluble group (x) include a repeating unit in which an alkali-soluble group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or a main group of the resin via a linking group. Examples include repeating units in which an alkali-soluble group is bonded to the chain. Furthermore, a polymerization initiator or a chain transfer agent having an alkali-soluble group can be used at the time of polymerization to be introduced at the end of the polymer chain. Is also preferable.

  The content of the repeating unit having an alkali-soluble group (x) is preferably from 1 to 50 mol%, more preferably from 3 to 35 mol%, still more preferably from 5 to 20 mol%, based on all repeating units in the polymer.

Specific examples of the repeating unit having an alkali-soluble group (x) are shown below, but the present invention is not limited thereto.

  (Y) Examples of the group that decomposes by the action of an alkali developer and increases the solubility in the alkali developer include a group having a lactone structure, an acid anhydride group, an acid imide group, and the like, and preferably a lactone A group having a structure.

  As the repeating unit having a group (y) that is decomposed by the action of an alkali developer and increases the solubility in the alkali developer, an alkali is added to the main chain of the resin, such as a repeating unit of an acrylate ester or a methacrylate ester. A polymerization initiator having a repeating unit to which a group (y) that decomposes by the action of the developer and increases the solubility in an alkali developer is bonded, or a group (y) that increases the solubility in an alkali developer And a chain transfer agent used at the time of polymerization are preferably introduced at the end of the polymer chain.

  The content of the repeating unit having a group (y) whose solubility in an alkali developer is increased is preferably 1 to 40 mol%, more preferably 3 to 30 mol%, still more preferably based on all repeating units in the polymer. 5 to 15 mol%.

Specific examples of the group (y) that increases the solubility in an alkali developer are shown below, but are not limited thereto.

  Examples of the repeating unit having a group (z) that can be decomposed by the action of an acid include the same repeating units having an acid-decomposable group as mentioned for the resin (P). In the compound (U), the content of the repeating unit having a group (z) that is decomposed by the action of an acid is preferably 1 to 80 mol%, more preferably 10 to 80 mol%, based on all repeating units in the polymer. Preferably it is 20-60 mol%.

  The weight average molecular weight in terms of standard polystyrene of the compound (U ′) is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, and still more preferably 2,000 to 15,000. .

  The compound (U ′), like the resin of the component (B), naturally has few impurities such as metals, and the residual monomer or oligomer component is preferably 0 to 10% by mass, more preferably 0-5 mass% and 0-1 mass% are still more preferable. Thereby, a resist having no change over time such as foreign matter in liquid or sensitivity can be obtained. The molecular weight distribution (Mw / Mn, also referred to as dispersity) is preferably in the range of 1 to 5, more preferably 1 to 3, and still more preferably from the viewpoints of resolution, resist shape, resist pattern sidewall, roughness, and the like. It is the range of 1-2.

  As the compound (U ′), various commercially available products can be used, or the compound (U ′) can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and the polymerization is performed by heating, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as the solvent used in the positive resist composition of the present invention. Thereby, the generation of particles during storage can be suppressed.

  The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred examples of the initiator include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. The concentration of the reaction is 5 to 50% by mass, preferably 30 to 50% by mass. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 60-100 ° C.

  After completion of the reaction, the mixture is allowed to cool to room temperature and purified. Purification can be accomplished by a liquid-liquid extraction method that removes residual monomers and oligomer components by combining water and an appropriate solvent, and a purification method in a solution state such as ultrafiltration that extracts and removes only those having a specific molecular weight or less. , Reprecipitation method that removes residual monomer by coagulating resin in poor solvent by dripping resin solution into poor solvent and purification in solid state such as washing filtered resin slurry with poor solvent A normal method such as a method can be applied. For example, the resin is precipitated as a solid by contacting a solvent (poor solvent) in which the resin is hardly soluble or insoluble in a volume amount of 10 times or less, preferably 10 to 5 times that of the reaction solution.

  The solvent (precipitation or reprecipitation solvent) used in the precipitation or reprecipitation operation from the polymer solution may be a poor solvent for the polymer, and may be a hydrocarbon, halogenated hydrocarbon, nitro, depending on the type of polymer. A compound, ether, ketone, ester, carbonate, alcohol, carboxylic acid, water, a mixed solvent containing these solvents, and the like can be appropriately selected for use. Among these, as a precipitation or reprecipitation solvent, a solvent containing at least an alcohol (particularly methanol or the like) or water is preferable.

  The amount of the precipitation or reprecipitation solvent used can be appropriately selected in consideration of efficiency, yield, and the like, but generally 100 to 10000 parts by mass, preferably 200 to 2000 parts by mass with respect to 100 parts by mass of the polymer solution, More preferably, it is 300-1000 mass parts.

  The temperature for precipitation or reprecipitation can be appropriately selected in consideration of efficiency and operability, but is usually about 0 to 50 ° C., preferably around room temperature (for example, about 20 to 35 ° C.). The precipitation or reprecipitation operation can be performed by a known method such as a batch method or a continuous method using a conventional mixing vessel such as a stirring tank.

  The precipitated or re-precipitated polymer is usually subjected to conventional solid-liquid separation such as filtration and centrifugation, and dried before use. Filtration is performed using a solvent-resistant filter medium, preferably under pressure. Drying is performed at a temperature of about 30 to 100 ° C., preferably about 30 to 50 ° C. under normal pressure or reduced pressure (preferably under reduced pressure).

  The resin may be once deposited and separated, and then dissolved again in a solvent, and the resin may be brought into contact with a hardly soluble or insoluble solvent. That is, after completion of the radical polymerization reaction, a solvent in which the polymer is hardly soluble or insoluble is brought into contact, the resin is precipitated (step a), the resin is separated from the solution (step b), and dissolved again in the solvent. (Step c), and then contact the resin solution A with a solvent in which the resin is hardly soluble or insoluble in a volume amount less than 10 times that of the resin solution A (preferably 5 times or less volume). This may be a method including precipitating a resin solid (step d) and separating the precipitated resin (step e).

  Hereinafter, examples of preferred resins as the compound (U ′) will be shown, but the invention is not limited thereto.

(F, Si type)

(Hydrocarbon)

Further, the compound (U) may be a low molecular compound having a triphenylene skeleton as shown below, for example. These compounds can be synthesized according to the method described in the liquid crystal manual.

A compound (U) may be used by 1 type and may be used in mixture of multiple types.
The content of the compound (U) is preferably 0.01 to 30% by mass, more preferably 0.1 to 20% by mass, based on the total solid content in the positive resist composition of the present invention. 15% by mass is particularly preferred.

<Other ingredients>
In the positive resist composition of the present invention, if necessary, a basic compound, a resin that decomposes by the action of an acid and increases the dissolution rate with respect to alkaline water solubility, a conventional photoacid generator, an organic solvent, A surfactant, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer, a photosensitizer, a dissolution promoting compound for a developer, a compound having a proton acceptor functional group, and the like can be contained.

<Basic compound>
The positive resist composition of the present invention may contain a basic compound in order to reduce the change in performance over time from exposure to heating, or to control the diffusibility of the acid generated by exposure in the film.

Preferable basic compounds include basic compounds having structures represented by the following general formulas (A) to (E).

Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² are each independently a hydrogen atom, an alkyl group (preferably 1 to 20 carbon atoms), a cycloalkyl group (preferably 3 to 20 carbon atoms) or an aryl group (preferably 6 to 20), and R ²⁵⁰ and R ²⁵¹ may be bonded to each other to form a ring.

These may have a substituent. Examples of the alkyl group and cycloalkyl group having a substituent include an aminoalkyl group having 1 to 20 carbon atoms, an aminocycloalkyl group having 3 to 20 carbon atoms, and 1 to 1 carbon atoms. A 20 hydroxyalkyl group or a C 3-20 hydroxycycloalkyl group is preferred.
These may contain an oxygen atom, a sulfur atom, or a nitrogen atom in the alkyl chain.

In the formula, R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ each independently represents an alkyl group (preferably having 1 to 6 carbon atoms) or a cycloalkyl group (preferably having 3 to 6 carbon atoms).

  Preferable compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, and piperidine, and may have a substituent. More preferable compounds include compounds having an imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, trialkylamine structure, aniline structure or pyridine structure, alkylamine derivatives having a hydroxyl group and / or an ether bond, hydroxyl groups and / or Or the aniline derivative which has an ether bond etc. can be mentioned.

  Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole, and the like. Examples of the compound having a diazabicyclo structure include 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] non-5-ene, and 1,8-diazabicyclo [5,4,0. ] Undec-7-ene. Examples of the compound having an onium hydroxide structure include triarylsulfonium hydroxide, phenacylsulfonium hydroxide, sulfonium hydroxide having a 2-oxoalkyl group, specifically triphenylsulfonium hydroxide, tris (t-butylphenyl) sulfonium. Examples thereof include hydroxide, bis (t-butylphenyl) iodonium hydroxide, phenacylthiophenium hydroxide, and 2-oxopropylthiophenium hydroxide. The compound having an onium carboxylate structure is a compound having an onium hydroxide structure in which the anion moiety is converted to a carboxylate, and examples thereof include acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine and tri (n-octyl) amine. Examples of aniline compounds include 2,6-diisopropylaniline and N, N-dimethylaniline. Examples of the alkylamine derivative having a hydroxyl group and / or an ether bond include ethanolamine, diethanolamine, triethanolamine, and tris (methoxyethoxyethyl) amine. Examples of aniline derivatives having a hydroxyl group and / or an ether bond include N, N-bis (hydroxyethyl) aniline.

  Further, at least one nitrogen-containing compound selected from an amine compound having a phenoxy group, an ammonium salt compound having a phenoxy group, an amine compound having a sulfonic acid ester group, and an ammonium salt compound having a sulfonic acid ester group can be exemplified. .

These compounds are preferably amine compounds in which at least one alkyl group is bonded to a nitrogen atom. Furthermore, it is preferable that the alkyl chain has an oxygen atom and an oxyalkylene group is formed. Preferable examples of these compounds include, but are not limited to, compounds (C1-1) to (C3-3) exemplified in [0066] of US2007 / 0224539A.

  Moreover, you may use a photosensitive basic compound as a basic compound. Although it does not specifically limit as a photosensitive basic compound, For example, Japanese translations of PCT publication No. 2003-524799 gazette, J.I. Photopolym. Sci & Tech. Vol. 8, P.I. 543-553 (1995) etc. can be used.

  The molecular weight of the basic compound is preferably 250 to 2000, and more preferably 400 to 1000.

These basic compounds are used alone or in combination of two or more.
The content of the basic compound is preferably 0 to 8.0% by mass, more preferably 0 to 5.0% by mass, particularly preferably 0 to 0% by mass with respect to the total solid content of the positive resist composition. It is 4.0 mass%.

<Resin that is decomposed by the action of an acid to increase the dissolution rate with respect to alkaline water solubility>
In addition to the resin (P), the positive resist composition of the present invention may contain a resin that decomposes by the action of an acid and increases the dissolution rate with respect to alkali water solubility.

  Resins that decompose due to the action of an acid and increase the dissolution rate in an alkaline aqueous solution (hereinafter also referred to as “acid-decomposable resins”) are not included in the main chain or side chain of the resin, or both of the main chain and side chain. It is a resin having a group (acid-decomposable group) that decomposes by the action of and produces an alkali-soluble group. Among these, a resin having an acid-decomposable group in the side chain is more preferable.

  The acid-decomposable resin is an acid soluble in an alkali-soluble resin as disclosed in European Patent No. 254853, JP-A-2-25850, JP-A-3-223860, JP-A-4-251259, and the like. It can be obtained by reacting a precursor of a group capable of decomposing, or copolymerizing an alkali-soluble resin monomer having an acid-decomposable group bonded thereto with various monomers.

  As the acid-decomposable group, for example, in a resin having an alkali-soluble group such as —COOH group and —OH group, a group in which the hydrogen atom of the alkali-soluble group shown on the left is substituted with a group capable of leaving by the action of an acid is preferable.

  Specifically, the acid-decomposable group is preferably the same group as the acid-decomposable group described in the above-described resin of the present invention (for example, the acid-decomposable group described as the repeating unit (B) in the resin (P)). As an example.

The resin having an alkali-soluble group is not particularly limited. For example, poly (o-hydroxystyrene), poly (m-hydroxystyrene), poly (p-hydroxystyrene) and copolymers thereof, hydrogenated poly (Hydroxystyrene), poly (hydroxystyrene) s having a substituent represented by the following structure, and resins having a phenolic hydroxyl group, styrene-hydroxystyrene copolymer, α-methylstyrene-hydroxystyrene copolymer, hydrogen An alkali-soluble resin having a hydroxystyrene structural unit such as a modified novolak resin, and an alkali-soluble resin containing a repeating unit having a carboxyl group such as (meth) acrylic acid or norbornenecarboxylic acid.

  The alkali dissolution rate of these alkali-soluble resins is preferably 17 nm / second or more as measured with 2.38 mass% tetramethylammonium hydroxide (TMAH) (23 ° C.). Particularly preferably, it is 33 nm / second or more.

  The alkali-soluble resin monomer is not particularly limited. For example, alkylcarbonyloxystyrene (for example, t-butoxycarbonyloxystyrene), alkoxystyrene (for example, 1-alkoxyethoxystyrene, t-butoxystyrene), (meta ) Acrylic acid tertiary alkyl ester (for example, t-butyl (meth) acrylate, 2-alkyl-2-adamantyl (meth) acrylate, dialkyl (1-adamantyl) methyl (meth) acrylate, etc.)) and the like.

  The content ratio of the group capable of decomposing with an acid is the number of repeating units (B) having a group decomposable with an acid in the resin and the number of repeating units having an alkali-soluble group not protected with a group capable of leaving with an acid. With (S), it is represented by B / (B + S). The content is preferably 0.01 to 0.7, more preferably 0.05 to 0.50, and still more preferably 0.05 to 0.40.

  The acid-decomposable resin is not particularly limited, but preferably has a repeating unit having an aromatic group, and is an acid-decomposable resin having hydroxystyrene as a repeating unit (for example, poly (hydroxystyrene / acid-decomposable group). (Hydroxystyrene) and poly (hydroxystyrene / (meth) acrylic acid protected with an acid-decomposable group)) are more preferred.

As the acid-decomposable resin, a resin having a repeating unit represented by the following general formula (VI) and a repeating unit represented by the general formula (I) is particularly preferable.

  The general formula (VI) is the same as the general formula (VI), and the general formula (I) is the same as the general formula (I).

  The acid-decomposable resin may have a repeating unit derived from another polymerizable monomer.

  The content of repeating units derived from other polymerizable monomers in the resin is generally 50 mol% or less, preferably 30 mol% or less, based on all repeating units. Examples of the repeating unit derived from another copolymerizable monomer that can be used include the same repeating unit as the repeating unit derived from the other polymerizable monomer.

  The content of the repeating unit having an alkali-soluble group such as a hydroxyl group, a carboxy group, or a sulfonic acid group is preferably 1 to 99 mol%, more preferably 3 to 95 mol% in all repeating units constituting the acid-decomposable resin. Especially preferably, it is 5-90 mol%.

  The content of the repeating unit having an acid-decomposable group is preferably from 3 to 95 mol%, more preferably from 5 to 90 mol%, particularly preferably from 10 to 85 mol% in all repeating units constituting the acid-decomposable resin. It is.

The weight average molecular weight of the acid-decomposable resin is preferably 50,000 or less, more preferably 1,000 to 20,000, and particularly preferably 1,000 to 10,000 as a polystyrene conversion value by the GPC method.
The dispersity (Mw / Mn) of the acid-decomposable resin is preferably 1.0 to 3.0, more preferably 1.05 to 2.0, and still more preferably 1.1 to 1.7.
Two or more acid-decomposable resins may be used in combination.
Although the preferable specific example of an acid-decomposable resin is shown below, it is not limited to these.

  In the positive resist composition of the present invention, the compounding amount of the acid-decomposable resin excluding the resin (P) is preferably 0 to 70% by mass, more preferably 0 to 50% in the total solid content of the composition. % By mass, still more preferably 0-30% by mass.

<Acid generator>
The positive resist composition of the present invention contains a resin (P) having a photoacid generating structure, but in addition to the resin (P), a low molecular compound that generates an acid upon irradiation with actinic rays or radiation. (Hereinafter also referred to as “acid generator”).

  Examples of such an acid generator include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or an actinic ray or radiation used for a microresist. A known compound that generates an acid by irradiation and a mixture thereof can be appropriately selected and used.

  Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

Among the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, compounds represented by the following general formulas (ZI ′), (ZII ′), and (ZIII ′) can be exemplified.

In general formulas (ZI ′) and (ZII ′),
R ₂₀₁ to R ₂₀₅ have the same meanings as R ₂₀₁ to R ₂₀₅ in formula (ZI) and (ZII).

X ⁻ represents a non-nucleophilic anion, preferably sulfonate anion, carboxylate anion, bis (alkylsulfonyl) amide anion, tris (alkylsulfonyl) methide anion, BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ^{− and the} like. Preferably, it is an organic anion containing a carbon atom.

More preferable organic anions include organic anions represented by the following general formulas (AN1) to (AN4).

In the general formulas (AN1) and (AN2), Rc ₁ represents an organic group.
Examples of the organic group in Rc ₁ include those having 1 to 30 carbon atoms, and preferably an alkyl group, an aryl group, or a plurality thereof, which may be substituted, is a single bond, —O—, —CO ₂ —, — _{S -, - SO 3 -,} - SO 2 N (Rd 1) - can be exemplified linked group a linking group such as.
Rd ₁ represents a hydrogen atom or an alkyl group, and may form a ring structure with the bonded alkyl group or aryl group.

The organic group of Rc ₁ is more preferably an alkyl group substituted at the 1-position with a fluorine atom or a fluoroalkyl group, or a phenyl group substituted with a fluorine atom or a fluoroalkyl group. By having a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by light irradiation is increased and the sensitivity is improved. When Rc ₁ has 5 or more carbon atoms, it is preferable that at least one carbon atom does not have all the hydrogen atoms replaced by fluorine atoms, but a part of the hydrogen atoms remains. It is more preferable that the number of is greater than that of fluorine atoms. By not having a perfluoroalkyl group having 5 or more carbon atoms, ecotoxicity is reduced.
The most preferred embodiment of Rc ₁ is a group represented by the following general formula.

In the above general formula,
Rc ₆ is substituted with a perfluoroalkylene group having 4 or less carbon atoms, more preferably 2 to 4 carbon atoms, still more preferably 2 to 3 carbon atoms, or 1 to 4 fluorine atoms and / or 1 to 3 fluoroalkyl groups. Represents a phenylene group.
Ax represents a linking group (preferably a single bond, —O—, —CO ₂ —, —S—, —SO ₃ —, —SO ₂ N (Rd ₁ ) —). Rd ₁ represents a hydrogen atom or an alkyl group, and may combine with Rc ₇ to form a ring structure.
Rc ₇ represents a hydrogen atom, a fluorine atom, an optionally substituted linear or branched alkyl group, a monocyclic or polycyclic cycloalkyl group or an aryl group. The optionally substituted alkyl group, cycloalkyl group and aryl group preferably do not contain a fluorine atom as a substituent.

In the general formulas (AN3) and (AN4),
Rc ₃ , Rc ₄ and Rc ₅ represent an organic group.
In the general formulas (AN3) and (AN4), the organic groups represented by Rc ₃ , Rc ₄ , and Rc ₅ are preferably the same as the preferred organic groups in Rc ₁ .

Rc ₃ and Rc ₄ may be bonded to form a ring.
Examples of the group formed by combining Rc ₃ and Rc ₄ include an alkylene group and an arylene group. Preferably, it is a C2-C4 perfluoroalkylene group. Rc ₃ and Rc ₄ are preferably bonded to form a ring, so that the acidity of the acid generated by light irradiation is increased and the sensitivity is improved, which is preferable.

In addition, the compound which has two or more structures represented by general formula (Z1 ') may be sufficient. For example, at least one of R _{201 to} R ₂₀₃ of the compound represented by the general formula (ZI ′) is bonded to 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.

In the general formula (ZIII ′),
R _{206 to} R ₂₀₇ each independently represents an aryl group, an alkyl group, or a cycloalkyl group.
The aryl group of R _{206 to} R ₂₀₇ is preferably a phenyl group or a naphthyl group, more preferably a phenyl group.
The alkyl group as R _{206 to} R ₂₀₇ may be either linear or branched, and is preferably a linear or branched alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group). Butyl group, pentyl group).

The cycloalkyl group as R _{206 to} R ₂₀₇ preferably includes a cycloalkyl group having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group).
Examples of the substituent that R _{206 to} R ₂₀₇ may have include an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), and an aryl group (for example, 6 to 6 carbon atoms). 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.

Among the compounds that generate an acid upon irradiation with actinic rays or radiation, compounds represented by the following general formulas (ZIV ′), (ZV ′), and (ZVI ′) can be further exemplified.

In general formulas (ZIV ′) to (ZVI ′),
Ar ₃ and Ar ₄ each independently represents an aryl group.

R _<208> represents an alkyl group, a cycloalkyl group, or an aryl group each independently.

R ₂₀₉ and R ₂₁₀ represent an alkyl group, a cycloalkyl group, an aryl group, or an electron-withdrawing group. R ₂₀₉ is preferably an aryl group. R ₂₁₀ is preferably an electron-withdrawing group, more preferably a cyano group or a fluoroalkyl group.
A represents an alkylene group, an alkenylene group or an arylene group.
These groups may have a substituent, and examples of the substituent include the same substituents that R _{204 to} R ₂₀₇ may have.

Among the compounds that generate an acid upon irradiation with actinic rays or radiation, more preferred are compounds represented by the general formulas (ZI ′), (ZIII ′), (ZVI ′), and even more preferred are the general formulas It is a compound represented by (ZI-1 ′), (ZIII ′), (ZVI ′).
Among the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, examples of particularly preferable compounds are listed below.

Moreover, the compound represented by the following general formula (A1) can also be mentioned as a preferable example of an acid generator.

In general formula (A1),
R ^{1a to} R ^13a each independently represents a hydrogen atom or a substituent, and at least one of R ^{1a to} R ^13a is a substituent containing an alcoholic hydroxyl group.
Za is a single bond or a divalent linking group.
X ⁻ represents a counter anion.
The alcoholic hydroxyl group in the present invention represents a hydroxyl group bonded to a carbon atom of an alkyl group.

When R < ^1a > -R <^13a> is a substituent containing an alcoholic hydroxyl group, R < ^1a > -R <^13a> is represented by -WY. However, Y is an alkyl group substituted with a hydroxyl group, and W is a single bond or a divalent linking group.

The alkyl group of Y is methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl Group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, boronyl group Preferably ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group and sec-butyl group, more preferably ethyl group, propyl group and isopropyl group. Y particularly preferably contains a —CH ₂ CH ₂ OH structure.

  The divalent linking group represented by W is not particularly limited, and examples thereof include an alkoxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an acylamino group, an aminocarbonylamino group, Alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, alkylthio group, arylthio group, sulfamoyl group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxy Examples thereof include a divalent group in which an arbitrary hydrogen atom in a monovalent group such as a carbonyl group, an alkoxycarbonyl group, or a carbamoyl group is replaced with a single bond.

  W is preferably a single bond, an alkoxy group, an acyloxy group, an acylamino group, an alkyl and arylsulfonylamino group, an alkylthio group, an alkylsulfonyl group, an acyl group, an alkoxycarbonyl group, and any hydrogen atom in the carbamoyl group replaced with a single bond. It is a divalent group, more preferably a divalent group in which any hydrogen atom in a single bond, acyloxy group, alkylsulfonyl group, acyl group or alkoxycarbonyl group is replaced with a single bond.

When R ^{1a to} R ^13a are a substituent containing an alcoholic hydroxyl group, the number of carbon atoms contained is preferably 2 to 10, more preferably 2 to 6, and particularly preferably 2 to 4. .

The substituent containing an alcoholic hydroxyl group as R ^{1a to} R ^13a may have two or more alcoholic hydroxyl groups. The number of alcoholic hydroxyl groups having a substituent containing an alcoholic hydroxyl group as R ^{1a to} R ^13a is 1 to 6, preferably 1 to 3, and more preferably 1. preferable.

The number of alcoholic hydroxyl groups contained in the compound represented by the general formula (A1) is 1 to 10 in total, preferably 1 to 6, more preferably 1 in total for R ^{1a to} R ^13a. It is three from.

When R ^{1a to} R ^13a do not contain an alcoholic hydroxyl group, R ^{1a to} R ^13a are each independently a hydrogen atom or a substituent, and any substituent may be used without any particular limitation. Halogen atoms, alkyl groups (including cycloalkyl groups, bicycloalkyl groups, and tricycloalkyl groups), alkenyl groups (including cycloalkenyl groups and bicycloalkenyl groups), alkynyl groups, aryl groups, heterocyclic groups (with heterocyclic groups and Cyano group, nitro group, carboxyl group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (Including anilino group), ammonio group, acylamino group, aminocarboni Ruamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and aryl Sulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, aryl and heterocyclic azo group, imide group, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino Group, phosphono group, silyl group, hydrazino group, ureido group, boronic acid group (—B (OH) ₂ ), phosphato group (—OPO (OH) ₂ ), sulfato group (—OSO ₃ H), and other known ones Substituents, for example .

Further, two adjacent ones of R ^{1a to} R ^13a are combined to form a ring (aromatic or non-aromatic hydrocarbon ring or heterocyclic ring. These are further combined to form a polycyclic fused ring. For example, benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, triphenylene ring, naphthacene 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, 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, Enantororin ring, thianthrene ring, chromene ring, xanthene ring, phenoxathiin ring, a phenothiazine ring and a phenazine ring.) May also be formed.

When R ^{1a to} R ^13a do not contain an alcoholic hydroxyl group, R ^{1a to} R ^13a are preferably a hydrogen atom or a halogen atom, an alkyl group (including a cycloalkyl group, a bicycloalkyl group, or a tricycloalkyl group), an alkenyl group. (Including cycloalkenyl groups and bicycloalkenyl groups), alkynyl groups, aryl groups, cyano groups, carboxyl groups, alkoxy groups, aryloxy groups, acyloxy groups, carbamoyloxy groups, acylamino groups, aminocarbonylamino groups, alkoxycarbonylamino groups , Aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, alkylthio group, arylthio group, sulfamoyl group, alkyl and arylsulfonyl group, aryloxycarbonyl group, alkoxycarbonyl Group, carbamoyl group, imide group, silyl group and ureido group.

When R ^{1a to} R ^13a do not contain an alcoholic hydroxyl group, R ^{1a to} R ^13a are more preferably a hydrogen atom or a halogen atom, an alkyl group (including a cycloalkyl group, a bicycloalkyl group, and a tricycloalkyl group), cyano Group, alkoxy group, acyloxy group, acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, alkyl and arylsulfonylamino group, alkylthio group, sulfamoyl group, alkyl and arylsulfonyl group, alkoxycarbonyl group and carbamoyl group.

Further, when R ^{1a to} R ^13a do not contain an alcoholic hydroxyl group, R ^{1a to} R ^13a are particularly preferably a hydrogen atom or an alkyl group (including a cycloalkyl group, a bicycloalkyl group, and a tricycloalkyl group), a halogen atom. And an alkoxy group.

In general formula (A1), at least one of R ^{1a to} R ^13a contains an alcoholic hydroxyl group, and preferably at least one of R ^{9 to} R ¹³ contains an alcoholic hydroxyl group.

Za represents a single bond or a divalent linking group, and examples of the divalent linking group include an alkylene group, an arylene group, a carbonyl group, a sulfonyl group, a carbonyloxy group, a carbonylamino group, a sulfonylamide group, an ether group, A thioether group, an amino group, a disulfide group, an acyl group, an alkylsulfonyl group, —CH═CH—, —C≡C—, an aminocarbonylamino group, an aminosulfonylamino group, and the like, and may have a substituent. . These substituents are the same as the substituents shown for R ^{1a to} R ^13a above. Za preferably has a single bond, an alkylene group, an arylene group, an ether group, a thioether group, an amino group, —CH═CH—, —C≡C—, an aminocarbonylamino group, an aminosulfonylamino group, or the like. A substituent, more preferably a single bond, an ether group or a thioether group, particularly preferably a single bond.

The counter anion as X ⁻ in the general formula (A1) is the same as the non-nucleophilic anion as X ⁻ in the acid generator and the acid generator represented by the general formula (ZI ′) or (ZI ″). Can be mentioned.
The molecular weight of the compound represented by the general formula (A1) is preferably 200 to 2000, and particularly preferably 400 to 1000.
Specific examples of the compound represented by the general formula (A1) include (A1) to (A36) exemplified in [0095] of US2007 / 0184384A as preferable examples. It is not limited to.

  The acid generator represented by the general formula (A1) can be synthesized, for example, according to the method described in [0090] of US2007 / 0184384A.

In the positive resist composition of the present invention, in addition to the resin (P) having a photoacid generating structure, when an acid generator is used, the acid generator is used alone or in combination of two or more. be able to. When two or more types are used in combination, it is preferable to combine two types of compounds that generate two types of organic acids that differ in the total number of atoms excluding hydrogen atoms by two or more.
The content of the acid generator in the composition is preferably 0 to 20% by mass, more preferably 0 to 10% by mass, and still more preferably 0 to 7% by mass based on the total solid content of the resist composition.

<Organic solvent>
The solvent that can be used in preparing the positive resist composition by dissolving each component is not particularly limited as long as it dissolves each component. For example, an alkylene glycol monoalkyl ether carboxylate ( Propylene glycol monomethyl ether acetate, etc.), alkylene glycol monoalkyl ether (propylene glycol monomethyl ether, etc.), lactic acid alkyl esters (ethyl lactate, methyl lactate, etc.), cyclic lactones (γ-butyrolactone, preferably 4-10 carbon atoms), Chain or cyclic ketones (2-heptanone, cyclohexanone, etc., preferably 4 to 10 carbon atoms), alkylene carbonates (ethylene carbonate, propylene carbonate, etc.), alkyl carboxylates (butyl acetate, etc.) Alkyl acetate is preferred), and the like alkoxy alkyl acetates (ethoxypropionate ethyl). Examples of other usable solvents include those described in US 2008/0248425 A1 [0244] and thereafter.

  Of the above, alkylene glycol monoalkyl ether carboxylates and alkylene glycol monoalkyl ethers are preferred.

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.
The solvent having a hydroxyl group is preferably an alkylene glycol monoalkyl ether, and the solvent having no hydroxyl group is preferably an alkylene glycol monoalkyl ether carboxylate.

<Surfactant>
The positive resist composition of the present invention further contains a 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].

  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 amount of the positive resist composition (excluding the solvent).

<Acid-decomposable dissolution inhibiting compound>
The positive resist composition of the present invention contains a dissolution-inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as “dissolution-inhibiting compound”) that decomposes by the action of an acid and increases the solubility in an alkaline developer. Can do.

  The dissolution inhibiting compound is preferably an alicyclic or aliphatic compound containing an acid-decomposable group, such as a cholic acid derivative containing an acid-decomposable group described in Proceeding of SPIE, 2724, 355 (1996). . Examples of the acid-decomposable group and alicyclic structure are the same as those described for the acid-decomposable resin.

  When the positive resist composition of the present invention is irradiated with an electron beam, it preferably contains a structure in which the phenolic hydroxyl group of the phenol compound is substituted with an acid-decomposable group. As a phenol compound, what contains 1-9 phenol frame | skeleton is preferable, More preferably, it contains 2-6 pieces.

The molecular weight of the dissolution inhibiting compound in the present invention is 3000 or less, preferably 300 to 3000, and more preferably 500 to 2500.
The addition amount of the dissolution inhibiting compound is preferably 0 to 50% by mass and more preferably 0 to 40% by mass with respect to the total solid content of the positive resist composition.
Specific examples of the dissolution inhibiting compound are shown below, but the present invention is not limited thereto.

<Dye>
In addition to these components, dyes such as oily dyes and basic dyes, photosensitizers, dissolution promoting compounds, and the like may be added.

  The dissolution accelerating compound for the developer that can be used in the present invention is a low molecular weight compound having a molecular weight of 1,000 or less and having two or more phenolic OH groups or one or more carboxy groups. When it has a carboxy group, an alicyclic or aliphatic compound is preferable. For examples, see JP-A-4-122938, JP-A-2-28531, US Pat. No. 4,916,210, European Patent 219294, and the like.

The preferable addition amount of these dissolution promoting compounds is 0 to 50% by mass, more preferably 0 to 30% by mass with respect to the acid-decomposable resin.
In addition, compounds having a proton acceptor functional group described in JP-A No. 2006-208781 and JP-A No. 2007-286574 can be suitably used for the composition of the present application.

<Pattern formation method>
The positive resist composition of the present invention is applied on a support such as a substrate to form a resist film. The thickness of the resist film is preferably 0.02 to 0.1 μm.
As a method of coating on the substrate, spin coating is preferable, and the rotation speed is preferably 1000 to 3000 rpm.

  For example, a positive resist composition is coated on a substrate (eg, silicon / silicon dioxide coating) used for manufacturing a precision integrated circuit element by an appropriate coating method such as a spinner or a coater, and dried to form a resist film. Form. In addition, a known antireflection film can be applied in advance.

  The resist film is usually irradiated with an electron beam (EB), X-rays or EUV light through a mask, preferably baked (heated) and developed. Thereby, a good pattern can be obtained. Note that with an electron beam (EB), drawing (direct drawing) without using a mask is common.

  In the development step, an alkaline developer is used as follows. As an alkaline developer of the resist composition, inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, Secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like Alkaline aqueous solutions such as quaternary ammonium salts, cyclic amines such as pyrrole and pihelidine can be used.

Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, the content of this invention is not limited by this.

Synthesis Example 1 (Synthesis of Monomer (M-1))
In 80 parts by mass of ethyl acetate, 10 parts by mass of p-hydroxystyrene and 0.01 parts by mass of p-toluenesulfonic acid / pyridine salt were dissolved at room temperature. While stirring this solution, a mixed solution of 6.1 parts by mass of ethyl vinyl ether and 20 parts by mass of ethyl acetate was added dropwise at room temperature. After dropping, the reaction was further allowed to proceed at room temperature for 24 hours.

  Triethylamine was added to the reaction solution to make it basic, and after washing with ion exchange water, the organic layer was concentrated and purified by column chromatography with hexane / ethyl acetate to obtain 10.5 mass of the following monomer (M-1). I got a part.

Synthesis Example 2 (Synthesis of monomer (M-2))
In Synthesis Example 1, the reaction was conducted in the same manner as in Synthesis Example 1 except that 10.7 parts by mass of cyclohexyl vinyl ether was used instead of ethyl vinyl ether, to obtain 12.3 parts by mass of the following monomer (M-2).

Synthesis Example 3 (Synthesis of monomer (M-3))
In Synthesis Example 1, the reaction was conducted in the same manner as in Synthesis Example 1 except that 13.1 parts by mass of 2-cyclohexylethyl vinyl ether was used instead of ethyl vinyl ether to obtain 14.7 parts by mass of the following monomer (M-3). It was.

Synthesis Example 4 (Synthesis of monomer (M-4))
In Synthesis Example 1, the reaction was carried out in the same manner as in Synthesis Example 1 except that 20.9 parts by mass of 2- (4-cyclohexylphenoxy) ethyl vinyl ether was used instead of ethyl vinyl ether, and the following monomer (M-4) was added to 19 .3 parts by mass were obtained.

Synthesis Example 5 (Synthesis of monomer (M-5))
50 parts by mass of triphenylsulfonium Br salt was dissolved in 50 parts by mass of methanol. To this liquid, a mixed liquid of 30 parts by mass of 4-styrenesulfonic acid Na salt, 50 parts by mass of methanol and 130 parts by mass of ion-exchanged water was added dropwise at room temperature with stirring.

  Extraction and washing were performed by adding ion-exchanged water and chloroform. After concentrating the organic layer, the precipitated solid was reslurried and filtered in hexane / ethyl acetate to obtain 48 parts by mass of the following monomer (M-5).

Synthesis Example 6 (Synthesis of monomer (M-6))
In Synthesis Example 5, the following monomer (M-6) was prepared in the same manner as in Synthesis Example 5 except that 50 parts by mass of triphenylsulfonium Br salt was changed to 61.3 parts by mass of 4,4-bis (methoxyphenyl) iodonium Br salt. ) Was obtained 65 parts by mass.

Synthesis Example 7 (Synthesis of monomer (M-7))
34 parts by mass of triphenylsulfonium Br salt was dissolved in a mixed solvent of 15 parts by mass of methanol and 15 parts by mass of ion-exchanged water. To this liquid, a mixed solution of 24 parts by mass of 3-sulfopropyl potassium methacrylate, 15 parts by mass of methanol and 15 parts by mass of ion-exchanged water was added dropwise at room temperature with stirring.

  After reacting for 2 hours, extraction and washing were performed by adding ion-exchanged water and chloroform. By concentrating the organic layer, 28 parts by mass of the following monomer (M-7) was obtained.

Synthesis Example 8 (Synthesis of monomer (M-8))
19.5 parts by mass of sulfanilic acid sodium salt was dissolved in 75 parts by mass of pyridine, 9.8 parts by mass of maleic anhydride was added to this solution, and the mixture was stirred at room temperature for 1 hour. Thereafter, 10.2 parts by mass of acetic anhydride was further added, and the mixture was heated and stirred at 80 ° C. for 4 hours. The reaction solution was poured into ion-exchanged water, and a large amount of sodium chloride was added to precipitate a solid. The obtained solid was collected by filtration and washed to obtain 4-phenylmaleimidesulfonic acid sodium salt.

  In the same manner as in Synthesis Example 7, 4-phenylmaleimidesulfonic acid sodium salt was subjected to an anion exchange reaction with triphenylsulfonium Br salt to obtain the following monomer (M-8).

Synthesis Example 9 (Synthesis of monomer (M-9))
9.8 parts by mass of maleic anhydride is dissolved in 200 parts by mass of tetrahydrofuran, 23.8 parts by mass of pyridine is added, 19.6 parts by mass of sodium 4-hydroxybenzenesulfonate is added, and the mixture is heated to reflux for 5 hours. It was. After allowing to cool, the reaction solution was poured into ion exchange water, and a large amount of sodium chloride was added to precipitate a solid. The obtained solid was collected by filtration and washed, and subjected to an anion exchange reaction with triphenylsulfonium Br salt in the same manner as in Synthesis Example 7 to obtain the following monomer (M-9).

Synthesis Example 10 (Synthesis of Resin (P-1))
4.66 parts by mass of 1-methoxy-2-propanol was heated to 80 ° C. under a nitrogen stream. While stirring this liquid, 2.98 parts by mass of 4-hydroxystyrene (hereinafter also referred to as “HOST”), 6.23 parts by mass of the monomer (M-1) obtained in Synthesis Example 1, and the above synthesis example Monomer (M-5) 0.79 parts by mass, 1-methoxy-2-propanol 18.6 parts by mass, dimethyl 2,2′-azobisisobutyrate [V-601, Wako Pure Chemical Industries, Ltd. )] 1.36 parts by mass of the mixed solution was added dropwise over 2 hours. After completion of dropping, the mixture was further stirred at 80 ° C. for 4 hours. After allowing the reaction solution to cool, 5.9 parts by mass of the resin (P-1) of the present invention was obtained by reprecipitation and vacuum drying with a large amount of hexane / ethyl acetate.

As a result of measuring ¹ H NMR of the obtained resin, as shown in FIG. 1, a peak considered to be derived from the OH group of 4-hydroxystyrene in the vicinity of 9.0 ppm, and the monomer (M-1) in the vicinity of 5.3 ppm. A peak considered to be derived from CH of the —O—CH (CH ₃ ) —O— group, a peak considered to be derived from the aryl group of the triarylsulfonium cation of the monomer (M-5) in the vicinity of 7.8 ppm, It was confirmed that the resin (P-1) was a resin composed of the following structural units. The composition ratio (molar ratio) of the resin was calculated from these peak area ratios. The weight average molecular weight (Mw: converted to polystyrene) determined from GPC (carrier: N-methyl-2-pyrrolidone (NMP)) is Mw = 15100, Mw / Mn (hereinafter also referred to as “MWD”) = 1. 72.

Synthesis Examples 11 to 22 (Synthesis of Resins (P-2) to (P-13))
Hereinafter, in the same manner as in Synthesis Example 10, resins (P-2) to (P-13) used in the present invention were synthesized.
Structural unit used, its preparation (parts by mass), polymerization concentration (reaction solution concentration: mass%), polymerization initiator preparation (parts by mass), composition ratio (molar ratio) of produced resin, weight average molecular weight (Mw) Table 1 below shows the number average molecular weight (Mn) and the dispersity (MWD).

Hereinafter, the structures, composition ratios, weight average molecular weights, and dispersities of the resins (P-1) to (P-13) of the present invention are shown.

Synthesis Examples 23 to 26 (Synthesis of resins (P-21), (P-22), (P-31), and (P-32))

P-21 was synthesized according to the method described in JP-A-2005-084365.
P-22 was synthesized according to the method described in J. Mater. Chem., Vol. 17, pages 1699-1706, 2007, and US2007 / 0117043A.
P-31 was synthesized according to the method described in JP-A-2002-072483.
P-32 was synthesized according to the method described in JP-A-10-111563.

[Reference Examples 1-22 and Comparative Examples 1-3]
<Resist preparation>
The components shown in Table 2 below were dissolved in the mixed solvent shown in Table 2, and this was filtered through a polytetrafluoroethylene filter having a pore size of 0.1 μm, and the total solid content concentration (% by mass) shown in Table 2 was obtained. The positive resist solution was prepared and evaluated as follows. The concentration (% by mass) of each component described in Table 2 is based on the total solid content. The addition amount of the surfactant is 0.05% by mass with respect to the total solid content of the positive resist solution.

<Resist evaluation (EB)>
The prepared positive resist solution is uniformly coated on a silicon substrate that has been subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 90 seconds to form a resist having a film thickness of 100 nm. A film was formed.

  This resist film was irradiated with an electron beam using an electron beam irradiation apparatus (HL750 manufactured by Hitachi, Ltd., acceleration voltage: 50 keV). Immediately after irradiation, it was heated on a hot plate at 110 ° C. for 90 seconds. Furthermore, development was performed at 23 ° C. for 60 seconds using an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass, rinsed with pure water for 30 seconds, and then dried to form a line and space pattern. Was evaluated by the following method.

〔sensitivity〕
The cross-sectional shape of the obtained pattern was observed using a scanning electron microscope (S-9220, manufactured by Hitachi, Ltd.). Sensitivity was defined as the minimum irradiation energy when resolving a 100 nm line (line: space = 1: 1).

[Resolution]
The resolving power was defined as the limiting resolving power (line and space were separated and resolving) at the irradiation dose showing the above sensitivity.

[Line edge roughness (LER)]
The distance from the reference line where there should be an edge, using a scanning electron microscope (S-9220, manufactured by Hitachi, Ltd.) for any 30 points in the length direction 50 μm of the 100 nm line pattern at the irradiation amount showing the sensitivity described above. Was measured, the standard deviation was obtained, and 3σ was calculated.

[Pattern shape]
The cross-sectional shape of the 100 nm line pattern at the irradiation dose showing the above sensitivity is observed using a scanning electron microscope (S-4300, manufactured by Hitachi, Ltd.), and evaluated in four stages: T-top, rectangular, slightly tapered, and tapered. Went.

[Outgas]
After exposure after giving an irradiation energy 1.5 times that of Eth, where Et is the minimum irradiation energy required to completely dissolve the coating film during development using the above equipment and process conditions. The outgas amount was simply evaluated from the film thickness reduction width (shrink film thickness). Since the shrink film thickness is correlated with the amount of components volatilized from the resist film by exposure, it can be seen that the smaller the shrink film thickness, the better the outgas characteristics.

[Static contact angle measurement of resist film]
Each resist composition shown in Table 4 was applied onto a silicon wafer and baked at 110 degrees for 60 seconds to form a 150 nm resist film. After dropping one drop of pure water on the obtained resist film, the static contact angle when 5 seconds passed was measured using an automatic contact angle meter (CA-V type manufactured by Kyowa Interface Chemical Co., Ltd.), θ / 2. The static contact angle of the resist film was obtained by automatic measurement by the method. Next, except that the ubiquitous compound (U) is not included, the contact angle of the resist composition is measured in the same manner for other compositions to obtain the static contact angle of the resist film when the ubiquitous compound (U) is not added. It was. These differences were determined by subtracting the static contact angle of the resist film when no ubiquitous compound (U) was added from the static contact angle value of the obtained resist film.

The structure of the raw material (unevenly distributed compound (U), other resin, conventional acid generator, basic compound) used in each composition is shown below.

  The surfactant and solvent used in each composition are shown below.

W-1: Megafac F176 (Dainippon Ink Chemical Co., Ltd., fluorine-based)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd., fluorine and silicon)
W-3: Polysiloxane polymer (Shin-Etsu Chemical Co., Ltd., silicon-based)
S1: Propylene glycol monomethyl ether acetate (PGMEA)
S2: Propylene glycol monomethyl ether (PGME)
From Table 3, it is apparent that the positive resist composition of the present invention simultaneously satisfies high sensitivity, high resolution, good pattern shape, good line edge roughness, and outgas reduction.

[Examples 1-2]
<Resist evaluation (EUV light)>
The components shown in Table 6 below were dissolved in the mixed solvent shown in Table 6, and this was filtered through a polytetrafluoroethylene filter having a pore size of 0.1 μm, and the total solid content concentration (% by mass) shown in Table 6 was obtained. The positive resist solution was prepared and evaluated as follows. The concentration (% by mass) of each component described in Table 6 is based on the total solid content. The addition amount of the surfactant is 0.05% by mass with respect to the total solid content of the positive resist solution.

  The prepared positive resist solution is uniformly coated on a silicon substrate that has been subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 90 seconds to form a resist having a film thickness of 100 nm. A film was formed.

  The resist film was irradiated with an EUV exposure apparatus (manufactured by RISOTEC Japan, wavelength 13 nm), and immediately after irradiation, heated on a hot plate at 110 ° C. for 90 seconds. Further, development was performed at 23 ° C. for 60 seconds using an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass, rinsed with pure water for 30 seconds, dried, and a line and space pattern (line: space = 1: 1) ) And the obtained pattern was evaluated by the following method.

〔sensitivity〕
The cross-sectional shape of the obtained pattern was observed using a scanning electron microscope (S-9220, manufactured by Hitachi, Ltd.). Sensitivity was defined as the minimum irradiation energy when resolving a 100 nm line (line: space = 1: 1).

[Pattern shape]
The cross-sectional shape of the 100 nm line pattern at the irradiation dose showing the above sensitivity is observed using a scanning electron microscope (S-4300, manufactured by Hitachi, Ltd.), and evaluated in four stages: T-top, rectangular, slightly tapered, and tapered. Went.

Claims (16)

Forming a film using an actinic ray or radiation sensitive resin composition for EUV or electron beam exposure;
Exposing the film using EUV light or an electron beam as an exposure light source; and
A pattern forming method comprising developing the exposed film,
As the actinic ray or radiation sensitive resin composition for EUV or electron beam exposure, the repeating unit (A) that decomposes upon irradiation with actinic rays or radiation to generate an acid, decomposes by the action of an acid, a repeating unit having a structure in which solubility increases (B) (P), and to a composition containing a compound which forms a ubiquitously protective film on the film surface by a film of (U), the repeating unit (A) has the structure which decomposes | disassembles by irradiation of the said actinic ray or radiation, and produces an acid anion in the side chain of resin (P), and the content rate of a compound (U) is total solid content in this composition. A pattern forming method using EUV or an actinic ray-sensitive or radiation-sensitive resin composition for electron beam exposure that is 0.01 to 30% by mass as a reference.   The pattern formation method according to claim 1, wherein the content of the compound (U) is 0.1 to 20% by mass based on the total solid content in the composition.   The pattern formation method of Claim 1 whose content rate of a compound (U) is 1-15 mass% on the basis of the total solid in the said composition. The pattern forming method according to claim 1, wherein the repeating unit (A) is a repeating unit represented by the following general formula (III).
Where
R ₀₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl group.
X ₁ ^′ represents a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, —O—, —SO ₂ —, —CO—, —N (R ₃₃ ) —. Or a divalent linking group in which a plurality of these are combined, and R ₃₃ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, substituted or unsubstituted A substituted aryl group or a substituted or unsubstituted aralkyl group is represented. However, X ₁ ^′ contains at least one arylene group.
A represents a structural site that is decomposed by irradiation with actinic rays or radiation to generate an acid anion in the side chain of the resin (P) . The pattern forming method according to claim 1, wherein the repeating unit (B) contains a group represented by —Ar—O—B ⁰ . Here, -Ar- represents a divalent aromatic group which may have a monocyclic or polycyclic substituent, B ⁰ represents A ⁰ or a -CO-O-A ⁰ group, and A ⁰ represents a —C (R ⁰¹ ) (R ⁰² ) (R ⁰³ ), —Si (R ⁰¹ ) (R ⁰² ) (R ⁰³ ) or —C (R ⁰⁴ ) (R ⁰⁵ ) —O—R ⁰⁶ group. R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R ⁰⁵ are the same or different and each represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group or an aryl group, and R ⁰⁶ represents an alkyl group or an aryl group. . However, at least two of R ^{01 to} R ⁰³ are groups other than hydrogen atoms, and two groups of R ^{01 to} R ⁰³ and R ^{04 to} R ⁰⁶ may be bonded to form a ring. Good. The pattern forming method according to claim 1, wherein the repeating unit (B) is a repeating unit represented by the following general formula (I).
In the formula, R ₀₁ , R ₀₂ and R ₀₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl. Represents a group. R ₀₃ represents a substituted or unsubstituted alkylene group, and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n Y's each independently represent a hydrogen atom or a group capable of leaving by the action of an acid. However, at least one of Y represents a group capable of leaving by the action of an acid.
n represents an integer of 1 to 4. The pattern forming method according to claim 1, wherein the resin (P) further has a repeating unit (C) represented by the following general formula (VI).
In the formula, R ₀₁ , R ₀₂ and R ₀₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl. Represents a group. R ₀₃ represents a substituted or unsubstituted alkylene group, and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n represents an integer of 1 to 4. The pattern forming method according to claim 1, wherein the compound (U) is a resin and has at least one group selected from the following groups (x) to (z).
(X) an alkali-soluble group,
(Y) a group that decomposes by the action of an alkali developer and increases the solubility in the alkali developer;
(Z) A group that decomposes by the action of an acid. The pattern forming method according to claim 1, wherein EUV light is used as the exposure light source. Resin (P) having a repeating unit (A) that decomposes upon irradiation with actinic rays or radiation to generate an acid, and a repeating unit (B) that has a structure that decomposes by the action of an acid and increases solubility in an alkaline aqueous solution And an actinic ray or radiation sensitive resin composition for EUV or electron beam exposure containing a compound (U) that is unevenly distributed on the film surface by film formation to form a protective film, wherein the repeating unit (A) is: The resin (P) has a structure that is decomposed by irradiation with the actinic ray or radiation to generate an acid anion in the side chain, and the content of the compound (U) is 0.01 based on the total solid content in the composition. a 30 wt%, and the repeating unit (B) is, ^-Ar-O-B feeling for EUV or electron beam exposure comprising a group represented by ⁰ actinic ray or radiation-sensitive resin composition. Here, -Ar- represents a divalent aromatic group which may have a monocyclic or polycyclic substituent, B ⁰ represents A ⁰ or a -CO-O-A ⁰ group, and A ⁰ represents a —C (R ⁰¹ ) (R ⁰² ) (R ⁰³ ), —Si (R ⁰¹ ) (R ⁰² ) (R ⁰³ ) or —C (R ⁰⁴ ) (R ⁰⁵ ) —O—R ⁰⁶ group. R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R ⁰⁵ are the same or different and each represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group or an aryl group, and R ⁰⁶ represents an alkyl group or an aryl group. . However, at least two of R ^{01 to} R ⁰³ are groups other than hydrogen atoms, and two groups of R ^{01 to} R ⁰³ and R ^{04 to} R ⁰⁶ may be bonded to form a ring. Good. The actinic ray-sensitive or radiation-sensitive resin composition for EUV or electron beam exposure according to claim 10 , wherein the content of the compound (U) is 0.1 to 20% by mass based on the total solid content in the composition. . The actinic ray or radiation sensitive resin composition for EUV or electron beam exposure according to claim 10 , wherein the content of the compound (U) is 1 to 15% by mass based on the total solid content in the composition. The actinic ray or radiation-sensitive resin composition for EUV or electron beam exposure according to any one of claims 10 to 12 , wherein the repeating unit (A) is a repeating unit represented by the following general formula (III). .
Where
R ₀₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl group.
X ₁ ^′ represents a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, —O—, —SO ₂ —, —CO—, —N (R ₃₃ ) —. Or a divalent linking group in which a plurality of these are combined, and R ₃₃ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, substituted or unsubstituted A substituted aryl group or a substituted or unsubstituted aralkyl group is represented. However, X ₁ ^′ contains at least one arylene group.
A represents a structural site that is decomposed by irradiation with actinic rays or radiation to generate an acid anion in the side chain of the resin (P) . The actinic ray or radiation sensitive resin composition for EUV or electron beam exposure according to any one of claims 10 to 13 , wherein the repeating unit (B) is a repeating unit represented by the following general formula (I). .
In the formula, R ₀₁ , R ₀₂ and R ₀₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl. Represents a group. R ₀₃ represents a substituted or unsubstituted alkylene group, and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n Y's each independently represent a hydrogen atom or a group capable of leaving by the action of an acid. However, at least one of Y represents a group capable of leaving by the action of an acid.
n represents an integer of 1 to 4. Resin (P) further comprises recurring units according to claim 10 ~ 14 EUV or electron beam exposure actinic rays or radiation-sensitive according to any one of having a (C) represented by the following general formula (VI) Resin composition.
In the formula, R ₀₁ , R ₀₂ and R ₀₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a halogen atom, a cyano group, or a substituted or unsubstituted alkoxycarbonyl. Represents a group. R ₀₃ represents a substituted or unsubstituted alkylene group, and may be bonded to Ar ₁ to form a 5-membered or 6-membered ring.
Ar ₁ represents an aromatic ring group.
n represents an integer of 1 to 4. The actinic ray for EUV or electron beam exposure according to any one of claims 10 to 15 , wherein the compound (U) is a resin and has at least one group selected from the following groups (x) to (z): Or a radiation sensitive resin composition.
(X) an alkali-soluble group,
(Y) a group that decomposes by the action of an alkali developer and increases the solubility in the alkali developer;
(Z) A group that decomposes by the action of an acid.