JP2009075429A - Positive resist composition, and pattern forming method using the positive resist composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive resist composition having good development defect performance and pattern formation in not only normal exposure but also liquid immersion exposure and having good development defect performance and pattern formation in double exposure, and to provide a pattern forming method using the positive resist composition. <P>SOLUTION: The positive resist composition contains (A) a compound generating acid by irradiation with active light or radiation, (B) a resin having 1-20 mol% of a repeating unit of a specific structure having a hydroxyl group to the whole repeating unit in the resin and increasing solubility to alkali developing solution by action of acid, and (C) a compound decomposed by action of acid, and generating acid. The pattern forming method using the positive resist composition is provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a positive resist composition whose properties change upon reaction with irradiation of actinic rays or radiation, and a pattern forming method using the positive resist composition. More specifically, a positive resist composition used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, another photofabrication process, a lithographic printing plate, an acid curable composition, and the The present invention relates to a pattern forming method using a positive resist composition.

  The chemically amplified resist composition generates an acid in the exposed area by irradiation with actinic rays or radiation such as far ultraviolet light, and a reaction solution using the acid as a catalyst to develop a developing solution for the irradiated and non-irradiated areas of the active light or radiation. It is a pattern forming material that changes the solubility in the substrate and forms a pattern on the substrate.

  When a KrF excimer laser is used as the exposure light source, the main component is a resin having a basic skeleton of poly (hydroxystyrene), which has a small absorption in the 248 nm region, and has a high sensitivity, high resolution, and good pattern. This is a better system than the conventional naphthoquinone diazide / novolak resin system.

  On the other hand, when a further short wavelength light source, for example, ArF excimer laser (193 nm) is used as the exposure light source, the compound having an aromatic group exhibits a large absorption in the 193 nm region. An ArF excimer laser resist containing a resin having a hydrocarbon structure has been developed. For example, in Patent Document 1 (Japanese Patent Laid-Open No. 2005-331918), Patent Document 2 (Japanese Patent Laid-Open No. 2004-184737), and Patent Document 3 (Japanese Patent Laid-Open No. 2003-330192), an alicyclic acid-decomposable repeating unit is used. Various properties have been improved by introducing a repeating unit having a spacer portion between the main chain and the acid-decomposable group.

As a technique for increasing the resolving power in an optical microscope, a so-called immersion method in which a high refractive index liquid (hereinafter also referred to as “immersion liquid”) is filled between a projection lens and a sample is known.
As for the "effect of immersion", the lambda ₀ is the wavelength of exposure light in air, the refractive index of the immersion liquid to air is n, the θ and convergence half of the light beam and when the NA ₀ = sin [theta, and immersion In this case, the resolution and the depth of focus can be expressed by the following equations.
(Resolving power) = k ₁ · (λ ₀ / n ₎ / NA ₀
(Depth of focus) = ± k ₂ · (λ ₀ / n ^{) /} NA ₀ ²
That is, the immersion effect is equivalent to using an exposure wavelength having a wavelength of 1 / n. In other words, in the case of a projection optical system with the same NA, the depth of focus can be increased n times by immersion. This is effective for all pattern shapes, and can be combined with a super-resolution technique such as a phase shift method and a modified illumination method which are currently being studied.

Examples of apparatuses in which this effect is applied to transfer of a fine image pattern of a semiconductor element are introduced in Patent Document 4 (Japanese Patent Laid-Open No. 57-153433), Patent Document 5 (Japanese Patent Laid-Open No. 7-220990), and the like. Yes.
Recent progress in immersion exposure technology is shown in Non-Patent Document 1 (SPIE Proc 4688, 11 (2002)) and Patent Document 6 (
International Publication No. 04-077158 Pamphlet). In the case of using an ArF excimer laser as a light source, pure water (refractive index of 1.44 at 193 nm) is considered to be most promising as an immersion liquid in terms of handling safety, transmittance at 193 nm, and refractive index. When an F ₂ excimer laser is used as a light source, a solution containing fluorine has been studied from the balance between transmittance and refractive index at 157 nm. However, a sufficient product has not yet been seen in terms of environmental safety and refractive index. It has not been issued. From the degree of immersion effect and the degree of completeness of the resist, the immersion exposure technique is considered to be installed in the ArF exposure machine earliest.

  In addition, when a chemically amplified resist is applied to immersion exposure, the resist layer comes into contact with the immersion liquid at the time of exposure, so that the resist layer is altered and components that adversely affect the immersion liquid are leached from the resist layer. Has been pointed out. Patent Document 7 (International Publication No. 04-068242 pamphlet) describes an example in which resist performance is changed by immersing a resist for ArF exposure in water before and after exposure, and points to a problem in immersion exposure. Yes.

As described above, water having a refractive index of 1.44 is adopted as a medium used for immersion exposure and filled between the projection lens and the semiconductor substrate from the viewpoint of availability and safety. Therefore, it is considered that patterning of semiconductor devices up to the generation with a design dimension of 45 nm is possible by using an exposure machine having a projection lens with NA of 1.2 to 1.35.
The next generation with a design dimension of 45 nm is 32 nm, and patterning of 32 nm generation semiconductor devices requires 1.65 NA, in which case it is filled between the projection lens and the semiconductor substrate. It is considered that the refractive index of the medium to be required is 1.8 or more.
However, a projection lens material having an NA of 1.65 is required to have a refractive index of 1.9 or higher, and LuAg is currently a promising candidate. However, there is a problem that the amount of absorbed light is large. It has not been solved yet.
Further, no media candidate having a refractive index of 1.8 or more has been found yet.

For this reason, a method using a special pattern forming method using an exposure machine having a projection lens having an NA of 1.2 to 1.35 is attracting attention for pattern formation of a 32 nm generation semiconductor device.
Several methods have been proposed for this special pattern forming method, and one of them is a double exposure process.
The double exposure process is a process in which the same photoresist film is exposed twice as described in Patent Document 8 (Japanese Patent Laid-Open No. 2002-75857). The pattern is divided into two groups, and the divided patterns are divided into two floors for exposure.
Patent Document 8 describes that it is essential for this method that the photosensitivity and solubility in a developing solution, such as a two-photon absorption resist, change in proportion to the square of the exposure intensity. A resist having such properties has not been developed yet.

JP 2005-331918 A Japanese Patent Laid-Open No. 2004-184637 JP 2003-330192 A JP-A-57-153433 JP-A-7-220990 International Publication No. 04-077158 Pamphlet International Publication No. 04-068242 Pamphlet JP 2002-75857 A Proc. SPIE, 2002, Vol. 4688, p. 11

An object of the present invention is to provide a positive resist composition having good development defect performance and pattern shape not only in normal exposure (dry exposure) but also in immersion exposure, and a pattern forming method using the positive resist composition Is to provide. Another object of the present invention is to provide a positive resist composition suitable for double exposure and having a good development defect performance and pattern shape in double exposure, and a pattern forming method using the positive resist composition.

  The present invention is as follows.

(1) (A) a compound that generates an acid upon irradiation with actinic rays or radiation,
(B) A resin having 1 to 20 mol% of a repeating unit represented by the following general formula (NGH-1) based on all repeating units in the resin, and having increased solubility in an alkali developer by the action of an acid and ( C) A positive resist composition comprising a compound that decomposes by the action of an acid to generate an acid.

In the general formula (NGH-1),
R _NGH1 represents a hydrogen atom or an alkyl group.
R _{NGH2 to} R _NGH4 each independently represents a hydrogen atom, an alkoxy group or a hydroxyl group. However, at least one of R _{NGH2 to} R _NGH4 represents a hydroxyl group.

  (2) The positive resist composition as described in (1), further comprising a surface-hydrophobized resin.

  (3) A pattern forming method comprising a step of forming a resist film with the positive resist composition according to (1) or (2), and exposing and developing the resist film.

  (4) A pattern forming method comprising a step of forming a resist film from the positive resist composition according to (1) or (2), and subjecting the resist film to immersion exposure and development.

  (5) A resist film is formed from the positive resist composition described in (1) or (2), a topcoat containing a surface hydrophobic resin is formed on the resist film, and immersion exposure and development are performed. The pattern formation method characterized by including a process.

  (6) A pattern forming method comprising a step of forming a resist film from the positive resist composition according to (1) or (2), and performing double exposure and development of the resist film.

  (7) A pattern forming method comprising a step of forming a resist film from the positive resist composition according to (1) or (2), and subjecting the resist film to immersion double exposure and development.

  (8) A resist film is formed from the positive resist composition described in (1) or (2), a topcoat containing a surface hydrophobizing resin is formed on the resist film, immersion double exposure, The pattern formation method characterized by including the process to develop.

  Furthermore, the following structures are mentioned as a preferable embodiment of this invention.

  (9) The compound (A) is a sulfonium salt of a fluorinated substituted alkane sulfonic acid, a fluorinated benzene sulfonic acid, a fluorinated imide acid or a fluorinated methide acid (1) or (2) The positive resist composition as described in 1. above.

  (10) The resin of (B) component further has an acid-decomposable repeating unit having a monocyclic or polycyclic alicyclic hydrocarbon structure. (1), (2) and (9) The positive resist composition according to any one of the above.

  (11) The positive type resin according to any one of (1), (2), (9) and (10), wherein the resin of component (B) further has a repeating unit having a lactone structure Resist composition.

  (12) The positive electrode according to any one of (1), (2) and (9) to (11), wherein the resin of component (B) further has a repeating unit having a hydroxyl group or a cyano group. Type resist composition.

  (13) The positive resist according to any one of (1), (2) and (9) to (12), wherein the resin of component (B) further has a repeating unit having a carboxyl group Composition.

  (14) The positive electrode according to any one of (1), (2) and (9) to (13), wherein the resin of component (B) further has a repeating unit having a hexafluoroisopropanol structure. Type resist composition.

  (15) (1), (2) and (9) to (9) further comprising a dissolution inhibiting compound having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer. The positive resist composition according to any one of (14).

  (16) The positive electrode according to any one of (1), (2) and (9) to (15), further comprising a basic compound and / or fluorine and / or a silicon-based surfactant. Type resist composition.

  (17) The basic compound has a compound having a structure selected from an imidazole structure, a diazabicyclo structure, an onium hydroxide structure, an onium carboxylate structure, a trialkylamine structure, an aniline structure, and a pyridine structure, a hydroxyl group and / or an ether bond. The positive resist composition as described in (16), which is an alkylamine derivative or an aniline derivative having a hydroxyl group and / or an ether bond.

  The present invention provides a positive resist composition having good development defect performance and pattern shape not only in normal exposure (dry exposure) but also in immersion exposure, and a pattern forming method using the positive resist composition. can do. Further, it is possible to provide a positive resist composition suitable for double exposure and a pattern forming method using the positive resist composition, which has good development defect performance and pattern shape in double exposure.

Hereinafter, the best mode for carrying out the present invention will be described.
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).

(A) Compound that generates acid upon irradiation with actinic ray or radiation The positive resist composition of the present invention contains a compound that generates acid upon irradiation with actinic ray or radiation (hereinafter also referred to as “acid generator”). To do.
As an acid generator, photo-initiator of photocation polymerization, photo-initiator of photo-radical polymerization, photo-decoloring agent of dyes, photo-discoloring agent, or irradiation with actinic ray or radiation used for micro-resist etc. Known compounds that generate acids and mixtures 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.

  Further, a group that generates an acid upon irradiation with these actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the polymer, for example, US Pat. No. 3,849,137, German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in JP-A 63-146029 can be used.

Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Preferred compounds among the acid generators include compounds represented by the following general formulas (ZI), (ZII), and (ZIII).

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 to 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. R _{201 to} R ₂₀₃
Examples of the group formed by combining two of these include an alkylene group (for example, a butylene group and a pentylene group).
Z ⁻ represents a non-nucleophilic anion.

Examples of the non-nucleophilic anion as Z ⁻ 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. This improves the temporal stability of the resist.

  Examples of the sulfonate anion include an aliphatic sulfonate anion, an aromatic sulfonate anion, and a camphor sulfonate anion.

  Examples of the carboxylate anion include an aliphatic carboxylate anion, an aromatic carboxylate anion, and an aralkylcarboxylate anion.

  The aliphatic moiety in the aliphatic sulfonate anion may be an alkyl group or a cycloalkyl group, preferably an alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms such as methyl. Group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, 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 and the like.

  The aromatic group in the aromatic sulfonate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

The alkyl group, cycloalkyl group and aryl group in the aliphatic sulfonate anion and aromatic sulfonate anion may have a substituent. Examples of the substituent of the alkyl group, cycloalkyl group, and aryl group in the aliphatic sulfonate anion and aromatic sulfonate anion include, for example, a nitro group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group , Hydroxyl group, amino group, cyano group, alkoxy group (preferably having 1 to 15 carbon atoms), cycloalkyl group (preferably having 3 to 15 carbon atoms), aryl group (preferably having 6 to 14 carbon atoms), alkoxycarbonyl group ( Preferably 2 to 7 carbon atoms, acyl group (preferably 2 to 12 carbon atoms), alkoxycarbonyloxy group (preferably 2 to 7 carbon atoms), alkylthio group (preferably 1 to 15 carbon atoms), alkylsulfonyl group (Preferably having 1 to 15 carbon atoms), alkyliminosulfonyl group (preferably having 2 to 15 carbon atoms), aryl Ruoxysulfonyl group (preferably having 6 to 20 carbon atoms), alkylaryloxysulfonyl group (preferably having 7 to 20 carbon atoms), cycloalkylaryloxysulfonyl group (preferably having 10 to 20 carbon atoms), alkyloxyalkyloxy group (Preferably having 5 to 20 carbon atoms), a cycloalkylalkyloxyalkyloxy group (preferably having 8 to 20 carbon atoms), and the like. About the aryl group and ring structure which each group has, an alkyl group (preferably C1-C15) can further be mentioned as a substituent.

  Examples of the aliphatic moiety in the aliphatic carboxylate anion include the same alkyl group and cycloalkyl group as in the aliphatic sulfonate anion.

  Examples of the aromatic group in the aromatic carboxylate anion include the same aryl group as in the aromatic sulfonate anion.

  The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 6 to 12 carbon atoms, such as a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylmethyl group.

  The alkyl group, cycloalkyl group, aryl group and aralkyl group in the aliphatic carboxylate anion, aromatic carboxylate anion and aralkylcarboxylate anion may have a substituent. Examples of the substituent of the alkyl group, cycloalkyl group, aryl group and aralkyl group in the aliphatic carboxylate anion, aromatic carboxylate anion and aralkylcarboxylate anion include, for example, the same halogen atom and alkyl as in the aromatic sulfonate anion Group, cycloalkyl group, alkoxy group, alkylthio group and the like.

  Examples of the sulfonylimide anion include saccharin anion.

  The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methyl anion is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, An isobutyl group, a sec-butyl group, a pentyl group, a neopentyl group, and the like can be given. Examples of substituents for these alkyl groups include halogen atoms, alkyl groups substituted with halogen atoms, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, cycloalkylaryloxysulfonyl groups, and the like. Alkyl groups substituted with fluorine atoms are preferred.

  Examples of other non-nucleophilic anions include fluorinated phosphorus, fluorinated boron, and fluorinated antimony.

Examples of the non-nucleophilic anion of Z ⁻ include an aliphatic sulfonate anion in which the α-position of the sulfonic acid is substituted with a fluorine atom, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group. A bis (alkylsulfonyl) imide anion substituted with a fluorine atom and a tris (alkylsulfonyl) methide anion wherein an alkyl group is substituted with a fluorine atom are preferred. The non-nucleophilic anion is more preferably a perfluoroaliphatic sulfonic acid anion having 4 to 8 carbon atoms, a benzenesulfonic acid anion having a fluorine atom, still more preferably a nonafluorobutanesulfonic acid anion, a perfluorooctanesulfonic acid anion, It is a pentafluorobenzenesulfonic acid anion and 3,5-bis (trifluoromethyl) benzenesulfonic acid anion.

Examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include a compound (ZI-1) described later.
), (ZI-2) and (ZI-3).

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (ZI) is, at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) It may be a compound.

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

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

In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or R ₂₀₁
Some of to R ₂₀₃ is an aryl group and the remainder may be an alkyl group or a cycloalkyl group.

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

  The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. The aryl group may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the 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 the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.

  The alkyl group or cycloalkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, such as a methyl group, Examples thereof include an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.

Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, more preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

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

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

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

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

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

  The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group).

R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

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

In 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 general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group or a cycloalkyl group.

Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group. Aryl group R ₂₀₄ to R ₂₀₇ 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 to R _207, 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).

Aryl group, alkyl group of R ₂₀₄ to R _207, cycloalkyl groups may have a substituent. Aryl group, alkyl group of R ₂₀₄ to R _207, 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 a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of Z ^{− in} formula (ZI).

  Examples of the acid generator further include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI).

In general formulas (ZIV) to (ZVI),
Ar ₃ and Ar ₄ each independently represents an aryl group.
R ₂₀₈ , R ₂₀₉ and R ₂₁₀ each independently represents an alkyl group, a cycloalkyl group or an aryl group.
A represents an alkylene group, an alkenylene group or an arylene group.

Among the acid generators, compounds represented by the general formulas (ZI) to (ZIII) are more preferable.
Further, the acid generator is preferably a compound that generates an acid having one sulfonic acid group or imide group, more preferably a compound that generates monovalent perfluoroalkanesulfonic acid, or a monovalent fluorine atom or fluorine atom. A compound that generates an aromatic sulfonic acid substituted with a group containing fluorinated acid, or a compound that generates a monovalent fluorine atom or imide acid substituted with a group containing a fluorine atom, and even more preferably, It is a sulfonium salt of a substituted alkanesulfonic acid, a fluorine-substituted benzenesulfonic acid, a fluorine-substituted imide acid or a fluorine-substituted methide acid. The acid generator that can be used is particularly preferably a fluorinated substituted alkane sulfonic acid, a fluorinated substituted benzene sulfonic acid or a fluorinated substituted imido acid whose pKa of the generated acid is pKa = -1 or less, and the sensitivity is improved. .

  Among acid generators, particularly preferred examples are given below.

An acid generator can be used individually by 1 type or in combination of 2 or more types.
The content of the acid generator in the positive resist composition is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, still more preferably, based on the total solid content of the positive resist composition. Is 1-7 mass%.

(B) Resin having 1 to 20 mol% of the repeating unit represented by the general formula (NGH-1) with respect to all repeating units in the resin, and having increased solubility in an alkaline developer by the action of an acid The positive resist composition has 1 to 20 mol% of a repeating unit represented by the following general formula (NGH-1) with respect to all repeating units in the resin, and the solubility in an alkali developer is increased by the action of an acid. Containing resin.

In the general formula (NGH-1),
R _NGH1 represents a hydrogen atom or an alkyl group.
R _{NGH2 to} R _NGH4 each independently represents a hydrogen atom, an alkoxy group or a hydroxyl group. However, at least one of R _{NGH2 to} R _NGH4 represents a hydroxyl group.

In the general formula (NGH-1), the alkyl group of _RNGH1 is preferably an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group and an ethyl group.
R _NGH1 is preferably _a hydrogen atom, a methyl group or an ethyl group, and more preferably _a methyl group.
The alkoxy group of R _NGH2 ~R _NGH4, methoxy group, an ethoxy group, a propoxy group, isopropoxy group, n- butoxy group, isobutoxy group, sec- butoxy group, t-butoxy group, octyloxy group, a dodecyloxy group Examples thereof include an alkoxy group having 1 to 20 carbon atoms and an alkoxy group having a substituent such as an ethoxyethoxy group. The alkoxy group preferably has 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms.
In the general formula (NGH-1), one or two of R _{NGH2 to} R _NGH4 are preferably a hydroxyl group and the rest are hydrogen atoms.

  Content of the repeating unit represented by general formula (NGH-1) is 1-20 mol% with respect to all the repeating units in resin, Preferably it is 5-15 mol%.

  The resin of the component (B) has a repeating unit represented by the general formula (NGH-1), whereby the substrate adhesion and the developer affinity are improved.

  Specific examples of the repeating unit represented by the general formula (NGH-1) are shown below, but the present invention is not limited thereto.

The resin of the component (B) is a resin whose solubility in an alkaline developer is increased by the action of an acid, and decomposes into the main chain or side chain of the resin or both the main chain and the side chain by the action of an acid, It is a resin having a group that generates an alkali-soluble group (hereinafter also referred to as “acid-decomposable group”).
Alkali-soluble groups include phenolic hydroxyl groups, carboxyl groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, (alkylsulfonyl) (alkylcarbonyl) imides. Group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) methylene group, etc. Is mentioned.
Preferred alkali-soluble groups include carboxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol), and sulfonic acid groups.
A preferable group as the acid-decomposable group is a group obtained by substituting the hydrogen atom of these alkali-soluble groups with a group capable of leaving with an acid.
Examples of the group leaving with an acid include -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), -C (R ₀₁ ) (R ₀₂ ). ) (OR ₃₉ ) and the like.
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 _{01 and} R ₀₂ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.
The acid-decomposable group is preferably a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like. More preferably, it is a tertiary alkyl ester group.

  The resin as the component (B) preferably has a repeating unit having an acid-decomposable group. The repeating unit having an acid-decomposable group is preferably a repeating unit represented by the following general formula (AI).

In general formula (AI),
Xa ₁ represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
T represents a single bond or a divalent linking group.
Rx _{1 to} Rx ₃ each independently represents an alkyl group (straight or branched) or a cycloalkyl group (monocyclic or polycyclic).
At least two of Rx _{1 to} Rx ₃ may combine to form a cycloalkyl group (monocyclic or polycyclic).

Examples of the divalent linking group for T include an alkylene group, —COO—Rt— group, —O—Rt— group, and the like. In the formula, Rt represents an alkylene group or a cycloalkylene group.
T is preferably a single bond or a —COO—Rt— group. Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a —CH ₂ — group or a — (CH ₂ ) ₃ — group.
The alkyl group of Rx _{1 to} Rx ₃ is preferably an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group.
Examples of the cycloalkyl group represented by Rx _{1 to} Rx ₃ include monocyclic cycloalkyl groups such as cyclopentyl group and cyclohexyl group, polycyclic cycloalkyl groups such as norbornyl group, tetracyclodecanyl group, tetracyclododecanyl group, and adamantyl group. Groups are preferred.
Examples of the cycloalkyl group formed by combining at least two of Rx _{1 to} Rx ₃ include a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, A polycyclic cycloalkyl group such as an adamantyl group is preferred.
It is preferable that Rx ₁ is a methyl group or an ethyl group, and Rx ₂ and Rx ₃ are bonded to form the above-described cycloalkyl group.

  As for content of the repeating unit which has an acid-decomposable group, 20-50 mol% is preferable with respect to all the repeating units in a polymer, More preferably, it is 25-45 mol%.

  Although the specific example of the repeating unit which has a preferable acid-decomposable group is shown below, this invention is not limited to this.

  The resin of component (B) preferably further has a repeating unit having at least one group selected from a lactone group and an alkali-soluble group.

The resin of component (B) preferably has a repeating unit having a lactone group.
Any lactone group can be used as long as it has a lactone structure, but it is preferably a 5- to 7-membered ring lactone structure, and forms a bicyclo structure or a spiro structure in the 5- to 7-membered ring lactone structure. The other ring structure is preferably condensed. It is more preferable to have a repeating unit having a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-16). The lactone structure may be directly bonded to the main chain. Preferred lactone structures are (LC1-1), (LC1-4), (LC1-5), (LC1-6), (LC1-13), (LC1-14), and a specific lactone structure is used. This improves line edge roughness and development defects.

The lactone structure moiety may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. More preferably, they are a C1-C4 alkyl group, a cyano group, and an acid-decomposable group. n2 represents an integer of 0 to 4. When n2 is 2 or more, a plurality of substituents (Rb ₂ ) may be the same or different, and a plurality of substituents (Rb ₂ ) may be bonded to form a ring.

  Examples of the repeating unit having a lactone structure represented by any one of the general formulas (LC1-1) to (LC1-16) include a repeating unit represented by the following general formula (AI).

In general formula (AI),
Rb ₀ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms. Preferred substituents that the alkyl group represented by Rb ₀ may have include a hydroxyl group and a halogen atom. Examples of the halogen atom for Rb ₀ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Rb ₀ is preferably a hydrogen atom or a methyl group.
Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent linking group obtained by combining these. Preferably a single bond, -Ab ₁ -CO ₂ - is a divalent linking group represented by. Ab ₁ is a linear, branched alkylene group, monocyclic or polycyclic cycloalkylene group, preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group or a norbornylene group.
V represents a group having a structure represented by any one of the general formulas (LC1-1) to (LC1-16).

  The repeating unit having a lactone group usually has an optical isomer, but any optical isomer may be used. One optical isomer may be used alone, or a plurality of optical isomers may be mixed and used. When one kind of optical isomer is mainly used, the optical purity (ee) thereof is preferably 90 or more, more preferably 95 or more.

  The content of the repeating unit having a lactone group is preferably from 15 to 60 mol%, more preferably from 20 to 50 mol%, still more preferably from 30 to 50 mol%, based on all repeating units in the polymer.

  Specific examples of the repeating unit having a lactone group are listed below, but the present invention is not limited thereto.

  Particularly preferred repeating units having a lactone group include the following repeating units. By selecting the optimum lactone group, the pattern profile and the density dependence become good.

The resin of component (B) preferably has a repeating unit having an alkali-soluble group. Examples of the alkali-soluble group include a carboxyl group, a sulfonamide group, a sulfonylimide group, a bisulsulfonylimide group, and an aliphatic alcohol (for example, hexafluoroisopropanol group) substituted with an electron-attracting group at the α-position. It is more preferable to have a repeating unit. By containing the repeating unit having an alkali-soluble group, the resolution in contact hole applications is increased. The repeating unit having an alkali-soluble group includes 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 an alkali in the main chain of the resin through a linking group. Either a repeating unit to which a soluble group is bonded, or a polymerization initiator or chain transfer agent having an alkali-soluble group is used at the time of polymerization and introduced at the end of the polymer chain, and the linking group is monocyclic or polycyclic. It may have a cyclic hydrocarbon structure. Particularly preferred are repeating units of acrylic acid or methacrylic acid.

  As for content of the repeating unit which has an alkali-soluble group, 1-20 mol% is preferable with respect to all the repeating units in a polymer, More preferably, it is 3-15 mol%, More preferably, it is 5-10 mol%.

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

  The resin of component (B) may further have a repeating unit that has an alicyclic hydrocarbon structure and does not exhibit acid decomposability. This can reduce the elution of low molecular components from the resist film to the immersion liquid during immersion exposure. Examples of such a repeating unit include 1-adamantyl (meth) acrylate, diamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and cyclohexyl (meth) acrylate repeating units.

  In addition to the above repeating structural unit, the resin of component (B) is dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required properties of resist, such as resolution, heat resistance, and sensitivity. Various repeating structural units can be included for the purpose of adjusting the above.

Examples of such repeating structural units include, but are not limited to, repeating structural units corresponding to the following monomers.

Thereby, the performance required for the resin of the component (B), in particular,
(1) Solubility in coating solvent,
(2) Film formability (glass transition point),
(3) Alkali developability,
(4) Membrane slip (hydrophobic, alkali-soluble group selection),
(5) Adhesion of unexposed part to substrate,
(6) Dry etching resistance,
Etc. can be finely adjusted.

  As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

  In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.

  In the component (B) resin, the molar ratio of each repeating structural unit is the resist dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general resist performance required for resolving power and heat resistance. In order to adjust the sensitivity and the like, it is set as appropriate.

  When the positive resist composition of the present invention is used for ArF exposure, the resin as the component (B) preferably has no aromatic group from the viewpoint of transparency to ArF light.

  As the resin of component (B), preferably, all the repeating units are composed of (meth) acrylate repeating units. In this case, all of the repeating units are methacrylate repeating units, all of the repeating units are acrylate repeating units, or all of the repeating units are methacrylate repeating units and acrylate repeating units. Although it can be used, the acrylate-based repeating unit is preferably 50 mol% or less of the total repeating units.

  (B) As resin of component, More preferably, it has 1-20 mol% of repeating units represented by general formula (NGH-1), and has an acid-decomposable group represented by general formula (AI) (meth) It is a copolymer containing 20 to 60 mol% of an acrylate-based repeating unit, 20 to 60 mol% of a (meth) acrylate-based repeating unit having a lactone group, and 0 to 20 mol% of another (meth) acrylate-based repeating unit.

The resin of component (B) can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method and a polymerization initiator are dissolved in a solvent and the polymerization is carried out by heating, and a solution of the monomer species and the polymerization initiator is added to the heating solvent over 1 to 10 hours. Examples include a dropping polymerization method that is added dropwise, and a 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. If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery. The concentration of the reaction is 5 to 50% by mass, preferably 10 to 30% by mass. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 60-100 ° C.

The weight average molecular weight of the component (B) resin is preferably 1,000 to 200,000, more preferably 2,000 to 20,000, and still more preferably 3,000 as a polystyrene-converted value by the GPC method. ˜15,000, particularly preferably 3,000 to 10,000. By setting the weight average molecular weight to 1,000 to 200,000, deterioration of heat resistance and dry etching resistance can be prevented, developability is deteriorated, and viscosity is increased, resulting in deterioration of film forming property. Can be prevented.
The degree of dispersion (molecular weight distribution) is usually 1 to 3, preferably 1 to 2, and more preferably 1.4 to 1.7. The smaller the molecular weight distribution, the better the resolution and the resist shape, and the smoother the side wall of the resist pattern, the better the roughness.

In the positive resist composition of the present invention, the blending amount of the component (B) resin in the entire composition is preferably 50 to 99.99% by mass, more preferably 60 to 99.0% by mass in the total solid content. It is.
In the present invention, the resin of component (B) may be used alone or in combination.

(C) Compound that decomposes by the action of an acid to generate an acid The positive resist composition of the present invention contains a compound that decomposes by the action of an acid to generate an acid (hereinafter also referred to as an “acid multiplying agent”). To do.
In the present invention, the acid proliferating agent is stable when no acid is present, but is decomposed by the action of an acid generated from the acid generator upon exposure to produce an acid. Here, the acid generated from the acid proliferating agent is preferably one having a high acid strength. Specifically, the acid dissociation constant (pKa) is preferably 3 or less, more preferably 2 or less. The acid generated from the acid proliferating agent is preferably a sulfonic acid having an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group.

  Examples of the acid proliferating agent include WO95 / 29968, WO98 / 24000, JP-A-8-305262, JP-A-9-34106, JP-A-8-248561, JP-A-8-503082, and US Pat. No. 5,445. No. 9,917, JP-A-8-503081, US Pat. No. 5,534,393, US Pat. No. 5,395,736, US Pat. No. 5,741,630, US Pat. No. 5,334,489 , U.S. Patent No. 5,582,956, U.S. Patent No. 5,578,424, U.S. Patent No. 5,453,345, U.S. Patent No. 5,445,917, European Patent No. 665,960, European Patent No. 757,628, European Patent No. 665,961, US Patent No. 5,667,943, Japanese Patent Application Laid-Open No. 10-1508, Japanese Patent Application Laid-Open No. 10-282642, Japanese Patent Application Laid-Open No. 9-512498. , Can be used in combination JP 2000-62337, one of the acid amplifier according to 2005-17730 Patent etc. JP, or two or more.

  Specifically, compounds represented by the following general formulas (1) to (6) are preferable.

In the general formulas (1) to (6),
R represents an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group.
R ₀ represents a group capable of leaving by the action of an acid.
R ₁ represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group,
Or represents an aryloxy group.
R ₂ represents an alkyl group or an aralkyl group.
R ₃ represents an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group.
R ₄ and R ₅ each independently represents an alkyl group, and R ₄ and R ₅ may be bonded to each other to form a ring.
R ₆ represents a hydrogen atom or an alkyl group.
R ₇ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group.
R ₈ represents an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group.
R ₉ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group.
R ₉ may combine with R ₇ to form a ring.
R ₁₀ represents an alkyl group, a cycloalkyl group, an alkoxy group, an aryl group, an aralkyl group, an aryloxy group or an alkenyloxy group.
R ₁₁ represents an alkyl group, a cycloalkyl group, an alkoxy group, an aryl group, an aralkyl group, an aryloxy group or an alkenyl group.
R ₁₀ and R ₁₁ may combine with each other to form a ring.
R ₁₂ represents an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, an alkynyl group or a cyclic imide group.

In the general formulas (1) to (6), examples of the alkyl group include an alkyl group having 1 to 8 carbon atoms, specifically a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, An octyl group etc. are mentioned.
Examples of the cycloalkyl group include cycloalkyl groups having 4 to 10 carbon atoms, and specifically include cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, adamantyl group, boronyl group, isobornyl group, tricyclo group. Examples include decanyl group, dicyclopentenyl group, nobornane epoxy group, menthyl group, isomenthyl group, neomenthyl group, tetracyclododecanyl group and the like.

Examples of the aryl group include aryl groups having 6 to 14 carbon atoms, and specific examples include a phenyl group, a naphthyl group, and a tolyl group.
Examples of the aralkyl group include aralkyl groups having 7 to 20 carbon atoms, and specific examples include a benzyl group, a phenethyl group, and a naphthylethyl group.
As an alkoxy group, a C1-C8 alkoxy group is mentioned, Specifically, a methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. are mentioned.
Examples of the alkenyl group include alkenyl groups having 2 to 6 carbon atoms, and specific examples include a vinyl group, a propenyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, and a cyclohexenyl group.

Examples of the aryloxy group include an aryloxy group having 6 to 14 carbon atoms, and specific examples include a phenoxy group and a naphthoxy group.
Examples of the alkenyloxy group include alkenyloxy groups having 2 to 8 carbon atoms, and specific examples include a vinyloxy group and an allyloxy group.

  Each of the above substituents may further have a substituent, and examples of the substituent include the following. That is, halogen atoms such as Cl, Br, and F, -CN group, -OH group, alkyl group having 1 to 4 carbon atoms, cycloalkyl group having 3 to 8 carbon atoms, and alkoxy group having 1 to 4 carbon atoms , Acylamino groups such as acetylamino group, aralkyl groups such as benzyl group and phenethyl group, allyloxyalkyl groups such as phenoxyethyl group, alkoxycarbonyl groups having 2 to 5 carbon atoms, acyloxy groups having 2 to 5 carbon atoms, etc. Can be mentioned. And the range of a substituent is not limited to these.

Examples of the ring formed by combining R ₄ and R ₅ with each other include a 1,3-dioxolane ring and a 1,3-dioxane ring.
Examples of the ring formed by combining R ₇ and R ₉ with each other include a cyclopentyl ring and a cyclohexyl ring.
Examples of the ring formed by combining R ₁₀ and R ₁₁ with each other include a 3-oxocyclohexenyl ring and a 3-oxoindenyl ring, which may contain an oxygen atom in the ring.
Examples of the group capable of leaving by the action of an acid of Ro include tertiary alkyl groups such as t-butyl group and t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxy group. 1-alkoxyethyl groups such as ethyl group, 1-cyclohexyloxyethyl group, alkoxymethyl groups such as 1-methoxymethyl group, 1-ethoxymethyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl group, 3- Examples thereof include an oxocyclohexyl group.

Preferred examples of each of R, R ₀ and R _{1 to} R ₁₁ include the following.
R: methyl group, ethyl group, propyl group, butyl group, octyl group, trifluoromethyl group, nonafluorobutyl group, heptadecafluorooctyl group, 2,2,2-trifluoroethyl group, phenyl group, pentafluorophenyl Group, methoxyphenyl group, toluyl group, mesityl group, fluorophenyl group, naphthyl group, cyclohexyl group, camphor group.
R ₀ : t-butyl group, methoxymethyl group, ethoxymethyl group, 1-ethoxyethyl group,
Tetrahydropyranyl group.
R ₁ : methyl group, ethyl group, propyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, phenyl group, naphthyl group, benzyl group, phenethyl group, methoxy group, ethoxy group, propoxy group, phenoxy group, naphthoxy group.
R ₂ : methyl group, ethyl group, propyl group, butyl group, benzyl group.
R ₃ : methyl group, ethyl group, propyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, phenyl group, naphthyl group, benzyl group, phenethyl group, naphthylmethyl group.
R ₄ , R ₅ : Methyl group, ethyl group, propyl group, those bonded to each other to form an ethylene group or a propylene group.
R ₆ : hydrogen atom, methyl group, ethyl group.

R ₇ , R ₉ : hydrogen atom, methyl group, ethyl group, propyl group, butyl group, pentyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, phenyl group, naphthyl group, benzyl group, phenethyl group, bonded to each other Forming a cyclopentyl ring or a cyclohexyl ring.
R ₈ : methyl group, ethyl group, isopropyl group, t-butyl group, neopentyl group, cyclohexyl group, phenyl group, benzyl group.
R ₁₀ : methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, methoxy group, ethoxy group, phenyl group, naphthyl group, benzyl group, phenoxy group, naphthoxy Group formed by forming a 3-oxocyclohexenyl ring or a 3-oxoindenyl ring, which may be bonded to each other to contain an oxygen atom.
R ₁₁ : methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, methoxy group, ethoxy group, phenyl group, naphthyl group, benzyl group, phenoxy group, naphthoxy A group formed by forming a 3-oxocyclohexenyl ring or a 3-oxoindenyl ring, which may be bonded to each other to contain an oxygen atom.

In the general formula (6), when R ₁₂ represents an alkyl group, examples of the alkyl group include linear and branched alkyl groups having 1 to 20 carbon atoms. Specific examples thereof include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, hexadecyl group, octadecyl group. , Eicosyl group, isopropyl group, isobutyl group, s-butyl group, t-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group and the like. . Among these, a linear alkyl group having 1 to 12 carbon atoms and a branched alkyl group having 3 to 12 carbon atoms are more preferable.
When R ₁₂ represents a cycloalkyl group, examples of the cycloalkyl group include cycloalkyl groups having 3 to 20 carbon atoms. Specific examples thereof include a cyclohexyl group, a cyclopentyl group, and a 2-norbornyl group. In these, a C5-C10 cycloalkyl group is more preferable.

When R ₁₂ represents a substituted alkyl group or a substituted cycloalkyl group, a monovalent nonmetallic atomic group other than hydrogen is used as the substituent. Preferred examples include halogen atoms (—F, —B
r, -Cl, -I), hydroxyl group, alkoxy group, aryloxy group, mercapto group, alkylthio group, arylthio group, alkyldithio group, aryldithio group, amino group, N-alkylamino group, N, N-dialkylamino Group, N-arylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N -Dialkylcarbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-arylcarbamoyloxy group, alkylsulfoxy group, arylsulfoxy group, acylthio group, acylamino group, N-alkylacylamino group, N -Aryl acylamino group, ureido N'-alkylureido group, N ', N'-dialkylureido group, N'-arylureido group, N', N'-diarylureido group, N'-alkyl-N'-arylureido group, N-alkyl Ureido group, N-arylureido group, N′-alkyl-N-alkylureido group, N′-alkyl-N-arylureido group, N ′, N′-dialkyl-N-alkylureido group, N ′, N ′ -Dialkyl-N-arylureido group, N'-aryl-N-alkylureido group, N'-aryl-N-arylureido group, N ', N'-diaryl-N-alkylureido group, N', N ' -Diaryl-N-arylureido group, N'-alkyl-N'-aryl-N-alkylureido group, N'-alkyl-N'-aryl-N-aryl Raid group, alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl-N-alkoxycarbonylamino group, N-alkyl-N-aryloxycarbonylamino group, N-aryl-N-alkoxycarbonylamino group, N- Aryl-N-aryloxycarbonylamino group, formyl group, acyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group N, N-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo group (—SO ₃ H) and conjugated salts thereof Group (hereinafter referred to as sulfonate group), alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group, N , N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group, N-arylsulfamoyl group, N, N-diarylsulfamoyl group, N-alkyl-N-arylsulfamoyl group, phosphono group (—PO ₃ H ₂ ) and its conjugate base group (hereinafter referred to as phosphonate group), dialkylphosphono group ( -PO ₃ (alkyl) _2), diaryl phosphono group _{(-PO 3 (aryl) 2)} , alkyl aryl phosphites A phono group (—PO ₃ (alkyl) (aryl)), a monoalkyl phosphono group (—PO ₃ H (alkyl)) and its conjugate base group (hereinafter referred to as an alkyl phosphonate group), a monoaryl phosphono group ( -PO ₃ H (aryl)) and its conjugated base group (hereinafter referred to as aryl phosphonophenyl group), phosphonooxy group (-OPO ₃ H ₂₎ and its conjugated base group (hereinafter referred to as phosphonophenyl group) , Dialkyl phosphonooxy group (—OPO ₃ (alkyl) ₂ ), diaryl phosphonooxy group (—OPO ₃ (aryl) ₂ ), alkylaryl phosphonooxy group (—OPO ₃ (alkyl) (aryl)), mono Alkylphosphonooxy group (—OPO ₃ H (alkyl)) and its conjugate base group (hereinafter referred to as alkylphosphonatooxy group), monoarylphosphonooxy group (—OPO ³ H (aryl)) and its conjugate base Base Hereinafter referred to as aryl phosphite Hona preparative group), a cyano group, a nitro group, an aryl group, an alkenyl group, an alkynyl group and the like.

Specific examples of the alkyl group in these substituents include the aforementioned alkyl groups, and specific examples of the aryl group include a phenyl group, a biphenyl group, a naphthyl group, a tolyl group, a xylyl group, a mesityl group, a cumenyl group, Chlorophenyl group, bromophenyl group, chloromethylphenyl group, hydroxyphenyl group, methoxyphenyl group, ethoxyphenyl group, phenoxyphenyl group, acetoxyphenyl group, benzoyloxyphenyl group, methylthiophenyl group, phenylthiophenyl group, methylaminophenyl Group, dimethylaminophenyl group, acetylaminophenyl group, carboxyphenyl group, methoxycarbonylphenyl group, ethoxyphenylcarbonyl group, phenoxycarbonylphenyl group, N-phenylcarbamoylphenyl group, phenyl group, Anofeniru group, sulfophenyl group, sulfonatophenyl group, phosphonophenyl phenyl group, and a phosphonophenyl phenyl group. Examples of the alkenyl group include vinyl group, 1-propenyl group, 1-butenyl group, cinnamyl group, 2-chloro-1-ethenyl group and the like. Examples of alkynyl group include ethynyl group, 1- A propynyl group, a 1-butynyl group, a trimethylsilylethynyl group, etc. are mentioned. Examples of R ₁₃ in the acyl group (R ₁₃ CO—) include hydrogen and the above alkyl group, cycloalkyl group, and aryl group.

  Among these substituents, more preferred are a halogen atom (—F, —Br, —Cl, —I), alkoxy group, aryloxy group, alkylthio group, arylthio group, N-alkylamino group, N, N -Dialkylamino group, acyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, acylamino group, formyl group, acyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group Group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, sulfo group, sulfonate group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfa group Moyl group, N-aryl sulf Moyl group, N-alkyl-N-arylsulfamoyl group, phosphono group, phosphonate group, dialkyl phosphono group, diaryl phosphono group, monoalkyl phosphono group, alkyl phosphonate group, monoaryl phosphono group, aryl phosphine group Examples include an onato group, a phosphonooxy group, a phosphonateoxy group, an aryl group, and an alkenyl group.

On the other hand, examples of the alkylene group in the substituted alkyl group include a divalent organic residue except for any one of the hydrogen atoms on the alkyl group having 1 to 20 carbon atoms, preferably A linear alkylene group having 1 to 12 carbon atoms, a branched chain having 3 to 12 carbon atoms, and a cyclic alkylene group having 5 to 10 carbon atoms can be exemplified. Preferable specific examples of the substituted alkyl group obtained by combining the substituent and the alkylene group include chloromethyl group, bromomethyl group, 2-chloroethyl group, trifluoromethyl group, methoxymethyl group, methoxyethoxyethyl group, allyl group. Oxymethyl group, phenoxymethyl group, methylthiomethyl group, tolylthiomethyl group, ethylaminoethyl group, diethylaminopropyl group, morpholinopropyl group, acetyloxymethyl group, benzoyloxymethyl group, N-cyclohexylcarbamoyloxyethyl group, N- Phenylcarbamoyloxyethyl group, acetylaminoethyl group, N-methylbenzoylaminopropyl group, 2-oxoethyl group, 2-oxopropyl group, carboxypropyl group, methoxycarbonylethyl group, allyloxy Rubonylbutyl group, chlorophenoxycarbonylmethyl group, carbamoylmethyl group, N-methylcarbamoylethyl group, N, N-dipropylcarbamoylmethyl group, N- (methoxyphenyl) carbamoylethyl group, N-methyl-N- (sulfophenyl) ) Carbamoylmethyl group, sulfobutyl group, sulfonatobutyl group, sulfamoylbutyl group, N-ethylsulfamoylmethyl group, N, N-dipropylsulfamoylpropyl group, N-tolylsulfamoylpropyl group, N-methyl- N- (phosphonophenyl) sulfamoyloctyl group, phosphonobutyl group, phosphonatohexyl group, diethylphosphonobutyl group, diphenylphosphonopropyl group, methylphosphonobutyl group, methylphosphonatobutyl group, tolylphosphono F Sil group, tolylphosphonatohexyl group, phosphonooxypropyl group, phosphonatooxybutyl group, benzyl group, phenethyl group, α-methylbenzyl group, 1-methyl-1-phenylethyl group, p-methylbenzyl group, cinnamyl Group, allyl group, 1-propenylmethyl group, 2-butenyl group, 2-methylallyl group, 2-methylpropenylmethyl group, 2-propynyl group, 2-butynyl group, 3-butynyl group and the like.

When R ₁₂ represents an aryl group, examples of the aryl group include those in which 1 to 3 benzene rings form a condensed ring, and those in which a benzene ring and a 5-membered unsaturated ring form a condensed ring. Specific examples include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, an indenyl group, an acenaphthenyl group, a fluorenyl group, and the like. Among these, a phenyl group and a naphthyl group are more preferable. The aryl group includes a heterocyclic (hetero) aryl group in addition to the carbocyclic aryl group. Examples of the heterocyclic aryl group include those having 3 to 20 carbon atoms and 1 to 5 hetero atoms such as a pyridyl group, a furyl group, and other quinolyl groups condensed with a benzene ring, a benzofuryl group, a thioxanthone group, and a carbazole group. Used.

When R ₁₂ represents a substituted aryl group, as the substituted aryl group, those having a monovalent nonmetallic atomic group excluding hydrogen as a substituent on the ring-forming carbon atom of the aforementioned aryl group are used. Examples of preferable substituents include those shown as the substituents in the aforementioned alkyl group and cycloalkyl group.

  Preferred examples of such a substituted aryl group include biphenyl group, tolyl group, xylyl group, mesityl group, cumenyl group, chlorophenyl group, bromophenyl group, fluorophenyl group, chloromethylphenyl group, trifluoromethylphenyl group. Hydroxyphenyl group, methoxyphenyl group, methoxyethoxyphenyl group, allyloxyphenyl group, phenoxyphenyl group, methylthiophenyl group, tolylthiophenyl group, ethylaminophenyl group, diethylaminophenyl group, morpholinophenyl group, acetyloxyphenyl group, Benzoyloxyphenyl group, N-cyclohexylcarbamoyloxyphenyl group, N-phenylcarbamoyloxyphenyl group, acetylaminophenyl group, N-methylbenzoylaminophenyl group, carbo Cyphenyl group, methoxycarbonylphenyl group, allyloxycarbonylphenyl group, chlorophenoxycarbonylphenyl group, carbamoylphenyl group, N-methylcarbamoylphenyl group, N, N-dipropylcarbamoylphenyl group, N- (methoxyphenyl) carbamoylphenyl group N-methyl-N- (sulfophenyl) carbamoylphenyl group, sulfophenyl group, sulfonatophenyl group, sulfamoylphenyl group, N-ethylsulfamoylphenyl group, N, N-dipropylsulfamoylphenyl group, N-tolylsulfamoylphenyl group, N-methyl-N- (phosphonophenyl) sulfamoylphenyl group, phosphonophenyl group, phosphonatophenyl group, diethylphosphonophenyl group, diphenylphosphono Enyl group, methylphosphonophenyl group, methylphosphonatophenyl group, tolylphosphonophenyl group, tolylphosphonatophenyl group, allyl group, 1-propenylmethyl group, 2-butenyl group, 2-methylallylphenyl group, 2- Examples thereof include a methylpropenylphenyl group, a 2-propynylphenyl group, a 2-butynylphenyl group, and a 3-butynylphenyl group.

When R ₁₂ represents an alkenyl group, a substituted alkenyl group [—C (R ₁₄ ) ═C (R ₁₅ ) (R ₁₆ )], an alkynyl group, or a substituted alkynyl group [—C≡C (R ₁₇ )], As R _{14 to} R ₁₇ , a monovalent nonmetallic atomic group can be used. Preferred examples of R _{14 to} R ₁₇ include a hydrogen atom, a halogen atom, an alkyl group, a substituted alkyl group, an aryl group, and a substituted aryl group. Specific examples thereof include those shown as the above-mentioned examples. More preferred substituents for R _{14 to} R ₁₇ include a hydrogen atom, a halogen atom, and a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms. Specific examples of the alkenyl group, substituted alkenyl group, alkynyl group and substituted alkynyl group include vinyl group, 1-butenyl group, 1-pentenyl group, 1-hexenyl group, 1-octenyl group, 1-methyl-1-propenyl group. 2-methyl-1-propenyl group, 2-methyl-1-butenyl group, 2-phenyl-1-ethenyl group, 2-chloro-1-ethenyl group, ethynyl group, propynyl group, phenylethyl group, etc. Can do.

When R ₁₂ represents a cyclic imide group, those having 4 to 20 carbon atoms such as succinic imide, phthalic imide, cyclohexane dicarboxylic imide, norbornene dicarboxylic imide can be used as the cyclic imide.

  Hereinafter, although the specific example of a compound represented by General formula (1)-(6) is illustrated, the content of this invention is not limited to these.

  In the present invention, the compound represented by the general formula (4) is particularly preferred as the acid proliferating agent.

  In the present invention, the addition amount of the acid proliferating agent in the composition is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, based on the total solid content of the composition. is there.

Solvents Solvents that can be used when preparing the positive resist composition by dissolving the above components include, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, lactate alkyl ester, alkoxypropionic acid. Examples thereof include organic solvents such as alkyl, a cyclic lactone having 4 to 10 carbon atoms, a monoketone compound having 4 to 10 carbon atoms, which may contain a ring, alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.

Examples of the alkylene glycol monoalkyl ether carboxylate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl Preferred examples include ether propionate, ethylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate.
Preferred examples of the alkylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether.

Preferred examples of the alkyl lactate include methyl lactate, ethyl lactate, propyl lactate and butyl lactate.
Preferable examples of the alkyl alkoxypropionate include ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, and ethyl 3-methoxypropionate.

  Examples of the cyclic lactone having 4 to 10 carbon atoms include β-propiolactone, β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone, β-methyl-γ-butyrolactone, γ-valerolactone, γ- Caprolactone, γ-octanoic lactone, and α-hydroxy-γ-butyrolactone are preferred.

  Examples of the monoketone compound having 4 to 10 carbon atoms which may contain a ring include 2-butanone, 3-methylbutanone, pinacolone, 2-pentanone, 3-pentanone, 3-methyl-2-pentanone, 4- Methyl-2-pentanone, 2-methyl-3-pentanone, 4,4-dimethyl-2-pentanone, 2,4-dimethyl-3-pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2 -Hexanone, 3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4 -Heptanone, 2-octanone, 3-octanone, 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5- Xen-2-one, 3-penten-2-one, cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone, 2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopenta Non, cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2,2-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone, 2-methylcyclo Preferred are heptanone and 3-methylcycloheptanone.

Preferred examples of the alkylene carbonate include propylene carbonate, vinylene carbonate, ethylene carbonate, and butylene carbonate.
Examples of the alkyl alkoxyacetate include 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2- (2-ethoxyethoxy) ethyl acetate, 3-methoxy-3-methylbutyl acetate, and 1-methoxy-acetate. 2-propyl is preferred.
Preferred examples of the alkyl pyruvate include methyl pyruvate, ethyl pyruvate, and propyl pyruvate.
As a solvent which can be preferably used, a solvent having a boiling point of 130 ° C. or higher under normal temperature and normal pressure can be mentioned. Specifically, cyclopentanone, γ-butyrolactone, cyclohexanone, ethyl lactate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate, ethyl pyruvate, 2-ethoxyethyl acetate, acetic acid -2- (2-ethoxyethoxy) ethyl and propylene carbonate are mentioned.
In the present invention, the above solvents may be used alone or in combination of two or more.

In this invention, you may use the mixed solvent which mixed the solvent which contains a hydroxyl group in a structure, and the solvent which does not contain a hydroxyl group as an organic solvent.
Examples of the solvent containing a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Particularly preferred are propylene glycol monomethyl ether and ethyl lactate.
Examples of the solvent not containing a hydroxyl group include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, and butyl acetate are particularly preferred, and propylene glycol monomethyl ether acetate, ethyl ethoxypropionate. 2-heptanone is most preferred.
The mixing ratio (mass) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60/40. . A mixed solvent containing 50% by mass or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.

  The solvent is preferably a mixed solvent of two or more containing propylene glycol monomethyl ether acetate.

Basic Compound The positive resist composition of the present invention preferably contains a basic compound in order to reduce the change in performance over time from exposure to heating.
Preferred examples of the basic compound include compounds having structures represented by the following formulas (A) to (E).

In general formulas (A) to (E),
R ²⁰⁰ , R ²⁰¹ and R ²⁰² may be the same or different, and are a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (having a carbon number). 6-20), wherein R ²⁰¹ and R ²⁰² may combine with each other to form a ring.
About the said alkyl group, as an alkyl group which has a substituent, a C1-C20 aminoalkyl group, a C1-C20 hydroxyalkyl group, or a C1-C20 cyanoalkyl group is preferable.
R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represents an alkyl group having 1 to 20 carbon atoms.
The alkyl groups in these general formulas (A) to (E) are more preferably unsubstituted.

Preferred compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, piperidine and the like, and more preferred compounds include imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate Examples thereof include a compound having a structure, a trialkylamine structure, an aniline structure or a pyridine structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, and an aniline derivative having a hydroxyl group and / or an ether bond.

Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, and benzimidazole. 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. ] Undecar 7-ene etc. are mentioned. 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. As the compound having an onium carboxylate structure, an anion portion of the compound having an onium hydroxide structure 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 the aniline compound include 2,6-diisopropylaniline, N, N-dimethylaniline, N, N-dibutylaniline, N, N-dihexylaniline and the like. 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.
These basic compounds are used alone or in combination of two or more.

  The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of solid content of a positive resist composition, Preferably it is 0.01-5 mass%.

  The use ratio of the acid generator and the basic compound in the composition is preferably acid generator / basic compound (molar ratio) = 2.5 to 300. In other words, the molar ratio is preferably 2.5 or more from the viewpoint of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing the reduction in resolution due to the thickening of the resist pattern over time until post-exposure heat treatment. The acid generator / basic compound (molar ratio) is more preferably 5.0 to 200, still more preferably 7.0 to 150.

Surfactant The positive resist composition of the present invention preferably further contains a surfactant, and a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant, silicon-based surfactant, fluorine atom and It is more preferable to contain any one or two or more of surfactants having both silicon atoms.

When the positive resist composition of the present invention contains the above surfactant, it provides a resist pattern with good sensitivity and resolution and less adhesion and development defects when using an exposure light source of 250 nm or less, particularly 220 nm or less. It becomes possible.
Examples of the fluorine-based and / or silicon-based surfactant include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.
Examples of commercially available surfactants that can be used include F-top EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431, 4430 (manufactured by Sumitomo 3M Co., Ltd.),
Megafuck F171, F173, F176, F189, F113, F110, F177, F120, R08 (manufactured by Dainippon Ink and Chemicals), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass ( Co., Ltd.), Troisol S-366 (manufactured by Troy Chemical Co., Ltd.), GF-300, GF-150 (manufactured by Toagosei Co., Ltd.), Surflon S-393 (manufactured by Seimi Chemical Co., Ltd.), Ftop EF121, EF122A, EF122B, RF122C, EF125M, EF135M, EF351, 352, EF801, EF802, EF601 (manufactured by Gemco), PF636, PF656, PF6320, PF6520 (manufactured by OMNOVA), FTX-204G, 208, 230G, 204 , Mention may be made of 208D, 212D, 218D, the fluorine-based surfactant or silicone-based surfactants such as 222D ((KK) Neos). Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, the surfactant is derived from a fluoroaliphatic compound produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₃ F ₇ group and (poly (oxy) And a copolymer of (ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate).

In the present invention, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, etc. Sorbitans such as polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopal Te - DOO, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, may be mentioned polyoxyethylene sorbitan tristearate nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as such.

  These surfactants may be used alone or in several combinations.

  The amount of the surfactant used is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass, based on the total amount of the positive resist composition (excluding the solvent).

Carboxylic acid onium salt The positive resist composition in the present invention may contain a carboxylic acid onium salt. Examples of the carboxylic acid onium salt include a carboxylic acid sulfonium salt, a carboxylic acid iodonium salt, and a carboxylic acid ammonium salt. In particular, as the carboxylic acid onium salt, an iodonium salt and a sulfonium salt are preferable. Furthermore, it is preferable that the carboxylate residue of the carboxylic acid onium salt of the present invention does not contain an aromatic group or a carbon-carbon double bond. As a particularly preferable anion moiety, a linear, branched, monocyclic or polycyclic alkylcarboxylic acid anion having 1 to 30 carbon atoms is preferable. More preferably, an anion of a carboxylic acid in which some or all of these alkyl groups are fluorine-substituted is preferable. The alkyl chain may contain an oxygen atom. This ensures transparency with respect to light of 220 nm or less, improves sensitivity and resolution, and improves density dependency and exposure margin.

  Fluoro-substituted carboxylic acid anions include fluoroacetic acid, difluoroacetic acid, trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid, nonafluoropentanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorocyclohexanecarboxylic acid, 2 , 2-bistrifluoromethylpropionic acid anion and the like.

  These carboxylic acid onium salts can be synthesized by reacting sulfonium hydroxide, iodonium hydroxide, ammonium hydroxide and carboxylic acid with silver oxide in a suitable solvent.

  The content of the carboxylic acid onium salt in the composition is generally 0.1 to 20% by mass, preferably 0.5 to 10% by mass, more preferably 1 to 7% by mass, based on the total solid content of the composition. %.

Dissolution-inhibiting compound having a molecular weight of 3000 or less that decomposes by the action of an acid to increase the solubility in an alkali developer. Dissolution-inhibiting compound having a molecular weight of 3000 or less that decomposes by the action of an acid to increase the solubility in an alkali developer. (Hereinafter, also referred to as “dissolution inhibitor compound”), such as a cholic acid derivative containing an acid-decomposable group described in ProceedingofSPIE, 2724,355 (1996), in order not to lower the permeability of 220 nm or less. An alicyclic or aliphatic compound containing an acid-decomposable group is preferred. Examples of the acid-decomposable group and alicyclic structure are the same as those described for the component (B) resin.

  When the positive resist composition of the present invention is exposed with a KrF excimer laser or 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 3 to 50% by mass, more preferably 5 to 40% by mass, based on the 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.

Other Additives In the positive resist composition of the present invention, if necessary, a dye, a plasticizer, a photosensitizer, a light absorber, and a compound that promotes solubility in a developer (for example, a molecular weight of 1000 or less) A phenol compound, an alicyclic compound having a carboxyl group, or an aliphatic compound).

Such phenol compounds having a molecular weight of 1000 or less are disclosed in, for example, JP-A-4-122929, JP-A-2-28531, U.S. Pat. No. 4,916,210, and European Patent No. 21929.
It can be easily synthesized by those skilled in the art with reference to the method described in 4 etc.
Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples thereof include, but are not limited to, dicarboxylic acids.

Pattern Forming Method The positive resist composition of the present invention is preferably used at a film thickness of 30 to 250 nm, more preferably at a film thickness of 30 to 200 nm, from the viewpoint of improving resolution. Such a film thickness can be obtained by setting the solid content concentration in the positive resist composition to an appropriate range to give an appropriate viscosity and improving the coating property and film forming property.
The total solid content concentration in the positive resist composition is generally 1 to 10% by mass, more preferably 1 to 8.0% by mass, and still more preferably 1.0 to 6.0% by mass.

  The positive resist composition of the present invention is used by dissolving the above components in a predetermined organic solvent, preferably the mixed solvent, filtering the solution, and then applying the solution on a predetermined support as follows. The filter used for filter filtration is preferably made of polytetrafluoroethylene, polyethylene, or nylon of 0.1 microns or less, more preferably 0.05 microns or less, and still more preferably 0.03 microns or less.

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.
The resist film is irradiated with actinic rays or radiation through a predetermined mask, preferably baked (heated), developed and rinsed. Thereby, a good pattern can be obtained.

Examples of the actinic ray or radiation include infrared light, visible light, ultraviolet light, far ultraviolet light, X-ray, electron beam, etc., preferably 250 nm or less, more preferably 220 nm or less, particularly preferably 1 to 1. Far ultraviolet light having a wavelength of 200 nm, specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-ray, electron beam, etc. ArF excimer laser, F ₂ Excimer laser, EUV (13 nm), and electron beam are preferable.

Before forming the resist film, an antireflection film may be coated on the substrate in advance.
As the antireflection film, any of an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, and amorphous silicon, and an organic film type made of a light absorber and a polymer material can be used. In addition, as the organic antireflection film, commercially available organic antireflection films such as DUV30 series, DUV-40 series manufactured by Brewer Science, AR-2, AR-3, AR-5 manufactured by Shipley, etc. may be used. it can.

In the development step, an alkaline developer is used as follows. Examples of the alkali developer for the positive resist composition include inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, and 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 Alkaline aqueous solutions of cyclic amines such as quaternary ammonium salts 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.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline aqueous solution.
As the rinsing liquid, pure water can be used, and an appropriate amount of a surfactant can be added.
Further, after the development process or the rinsing process, a process of removing the developer or the rinsing liquid adhering to the pattern with a supercritical fluid can be performed.

  Exposure (immersion exposure) may be performed by filling a liquid (immersion medium) having a higher refractive index than air between the resist film and the lens during irradiation with actinic rays or radiation. Thereby, resolution can be improved. As the immersion medium to be used, any liquid can be used as long as it has a higher refractive index than air, but pure water is preferred.

The immersion liquid used for the immersion exposure will be described below.
The immersion liquid is preferably a liquid that is transparent to the exposure wavelength and has a refractive index temperature coefficient as small as possible so as to minimize distortion of the optical image projected onto the resist film. Is an ArF excimer laser (wavelength; 193 nm), it is preferable to use water from the viewpoints of availability and ease of handling in addition to the above-mentioned viewpoints.
Further, a medium having a refractive index of 1.5 or more can be used in that the refractive index can be further improved. This medium may be an aqueous solution or an organic solvent.

  When water is used as the immersion liquid, the surface tension of the water is decreased and the surface activity is increased, so that the resist film on the wafer is not dissolved and the influence on the optical coating on the lower surface of the lens element can be ignored. An additive (liquid) may be added in a small proportion. The additive is preferably an aliphatic alcohol having a refractive index substantially equal to that of water, and specifically includes methyl alcohol, ethyl alcohol, isopropyl alcohol and the like. By adding an alcohol having a refractive index substantially equal to that of water, even if the alcohol component in water evaporates and the content concentration changes, an advantage that the change in the refractive index of the entire liquid can be made extremely small can be obtained. On the other hand, when an opaque material or impurities whose refractive index is significantly different from that of water are mixed with 193 nm light, the optical image projected on the resist film is distorted. . Further, pure water filtered through an ion exchange filter or the like may be used.

The electrical resistance of water is desirably 18.3 MQcm or more, the TOC (organic substance concentration) is desirably 20 ppb or less, and deaeration treatment is desirably performed.
Moreover, it is possible to improve lithography performance by increasing the refractive index of the immersion liquid. From such a viewpoint, an additive for increasing the refractive index may be added to water, or heavy water (D ₂ O) may be used instead of water.

  When the resist film made of the positive resist composition of the present invention is exposed through an immersion medium, a surface hydrophobizing resin (HR) can be further added as necessary. As a result, surface hydrophobic resin (HR) is unevenly distributed on the surface of the resist film, and when the immersion medium is water, the receding contact angle of the resist film surface with respect to water when the resist film is formed is improved, and the immersion water followability is improved. Can be improved. As the surface hydrophobizing resin (HR), any resin can be used as long as the receding contact angle of the surface can be improved by addition, but a resin having at least one of fluorine atom and silicon atom is preferable. The receding contact angle of the resist film is preferably 60 ° to 90 °, more preferably 70 ° or more. The addition amount can be adjusted and used as appropriate so that the receding contact angle of the resist film falls within the above range, but is preferably 0.1 to 10% by mass based on the total solid content of the positive resist composition, More preferably, it is 0.1-5 mass%. Surface hydrophobic resin (HR) is ubiquitous at the interface as described above, but unlike surfactants, it does not necessarily have a hydrophilic group in the molecule, and polar / nonpolar substances are mixed uniformly. It does not have to contribute to

  The fluorine atom or silicon atom in the surface hydrophobized resin (HR) may be present in the main chain of the resin or may be substituted on the side chain.

The surface hydrophobizing resin (HR) is preferably a resin having an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or an aryl group having a fluorine atom as a partial structure having a fluorine atom.
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.

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 .

The surface hydrophobizing resin (HR) is preferably a resin having an alkylsilyl structure (preferably a trialkylsilyl group) or a cyclic siloxane structure as a partial structure having a silicon atom.
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 phenyl 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.

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

Furthermore, the surface hydrophobized resin (HR) may 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 group having 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. It is preferable to use a repeating unit in which an alkali-soluble group is bonded to the chain, and further introduce a polymerization initiator or chain transfer agent having an alkali-soluble group at the end of the polymer chain at the time of polymerization.
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, an acid imide group, and the like, and preferably a lactone group It is.
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 repeating unit having a group (y) that increases the solubility in an alkali developer include the same repeating units as those having a lactone structure exemplified for the resin of the component (B).

  In the surface hydrophobized resin (HR), examples of the repeating unit having a group (z) that is decomposed by the action of an acid are the same as the repeating unit having an acid-decomposable group exemplified in the resin of the component (B). It is done. In the surface hydrophobized resin (HR), 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%, based on all repeating units in the polymer. It is -80 mol%, More preferably, it is 20-60 mol%.

  The surface hydrophobizing resin (HR) may further have a repeating unit represented by the following general formula (III).

In general formula (III):
R ₄ represents a group having an alkyl group, a cycloalkyl group, an alkenyl group, or a cycloalkenyl group.
L ₆ represents a single bond or a divalent linking group.

In general formula (III), the alkyl group represented by R ₄ is preferably a linear or branched alkyl group having 3 to 20 carbon atoms.
The cycloalkyl group is preferably a cycloalkyl group having 3 to 20 carbon atoms.
The alkenyl group is preferably an alkenyl group having 3 to 20 carbon atoms.
The cycloalkenyl group is preferably a cycloalkenyl group having 3 to 20 carbon atoms.
The divalent linking group of L ₆ is preferably an alkylene group (preferably having 1 to 5 carbon atoms) or an oxy group.

When the surface hydrophobized resin (HR) has a fluorine atom, the fluorine atom content is preferably 5 to 80% by mass with respect to the molecular weight of the surface hydrophobized resin (HR), and is 10 to 80% by mass. More preferably. Moreover, it is preferable that the repeating unit containing a fluorine atom is 10-100 mass% in surface hydrophobization resin (HR), and it is more preferable that it is 30-100 mass%.
When surface hydrophobic resin (HR) has a silicon atom, it is preferable that content of a silicon atom is 2-50 mass% with respect to the molecular weight of surface hydrophobic resin (HR), and is 2-30 mass%. More preferably. Moreover, it is preferable that it is 10-100 mass% in a surface hydrophobic resin (HR), and, as for the repeating unit containing a silicon atom, it is more preferable that it is 20-100 mass%.

  The weight average molecular weight in terms of standard polystyrene of the surface hydrophobized resin (HR) is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, still more preferably 2,000 to 15,000. It is.

  The surface hydrophobized resin (HR), 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 it is 0-5 mass%, and 0-1 mass% is 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 surface hydrophobizing resin (HR), various commercially available products can be used, and they 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).

  Specific examples of the surface hydrophobized resin (HR) are shown below. Table 1 below shows the molar ratio of the repeating units in each resin (corresponding to each repeating unit in order from the left), the weight average molecular weight, and the degree of dispersion.

Since the resist film is not directly brought into contact with the immersion liquid between the resist film of the positive resist composition of the present invention and the immersion liquid, it is also referred to as an “immersion liquid hardly soluble film” (hereinafter referred to as “top coat”). ) May be provided. The necessary functions for the top coat are suitability for application to the upper layer of the resist, radiation, especially transparency to 193 nm, and poor immersion liquid solubility. It is preferable that the top coat is not mixed with the resist and can be uniformly applied to the resist upper layer.
From the viewpoint of 193 nm transparency, the top coat is preferably a polymer that does not contain abundant aromatics. Specifically, the polymer contains a hydrocarbon polymer, an acrylate polymer, polymethacrylic acid, polyacrylic acid, polyvinyl ether, and silicon. Examples thereof include a polymer and a fluorine-containing polymer. The aforementioned surface hydrophobized resin (HR) is also suitable as a top coat. From the viewpoint of contaminating the optical lens when impurities are eluted from the top coat into the immersion liquid, it is preferable that the residual monomer component of the polymer contained in the top coat is small.

When peeling the top coat, a developer may be used, or a separate release agent may be used. As the release agent, a solvent having a small penetration into the resist film is preferable. It is preferable that the peeling process can be performed with an alkali developer in that the peeling process can be performed simultaneously with the resist film development process. From the viewpoint of peeling with an alkaline developer, the topcoat is preferably acidic, but may be neutral or alkaline from the viewpoint of non-intermixability with the resist film.
The resolution is improved when there is no difference in refractive index between the top coat and the immersion liquid. In the case of using water as the immersion liquid in an ArF excimer laser (wavelength: 193 nm), the top coat for ArF immersion exposure is preferably close to the refractive index of the immersion liquid. From the viewpoint of making the refractive index close to the immersion liquid, it is preferable to have fluorine atoms in the topcoat. A thin film is more preferable from the viewpoint of transparency and refractive index.

  The top coat is preferably not mixed with the resist film and further not mixed with the immersion liquid. From this point of view, when the immersion liquid is water, the solvent used for the top coat is preferably a water-insoluble medium that is hardly soluble in the solvent used for the positive resist composition. Furthermore, when the immersion liquid is an organic solvent, the topcoat may be water-soluble or water-insoluble.

In the present invention, the double exposure process is a process in which exposure is performed twice on the same photoresist film as described in JP-A-2002-75857. In this method, the pattern is divided into groups, and the divided patterns are exposed twice. As shown in FIG. 1, a specific dividing method is, for example, by exposing twice a pattern of 60 nm lines and 180 nm spaces using two masks shifted by 120 nm to obtain 60 nm lines.
A 1: 1 line and space pattern is formed. In general, the optical resolution decreases with decreasing pattern pitch (120 nm for a 1: 1 line and space pattern of 60 nm), but in double exposure, each divided pattern is 2 The pitch is doubled and the resolution is improved.

The positive resist composition of the present invention may be applied to a multilayer resist process (particularly a three-layer resist process). The multilayer resist method includes the following processes.
(a) A lower resist layer made of an organic material is formed on a substrate to be processed.
(b) On the lower resist layer, an intermediate layer and an upper resist layer made of an organic material that crosslinks or decomposes upon irradiation are sequentially laminated.
(c) After forming a predetermined pattern in the upper resist layer, the intermediate layer, the lower layer and the substrate are sequentially etched.
As the intermediate layer, organopolysiloxane (silicone resin) or SiO ₂ is generally used.
A coating solution (SOG) is used. As the lower layer resist, an appropriate organic polymer film is used, but various known photoresists may be used. For example, each series of the Fuji Film Arch FH series, FHi series, or Sumitomo Chemical PFI series can be illustrated.
The film thickness of the lower resist layer is preferably 0.1 to 4.0 μm, more preferably 0.2 to 2.0 μm, and particularly preferably 0.25 to 1.5 μm. A thickness of 0.1 μm or more is preferable from the viewpoint of antireflection and dry etching resistance, and a thickness of 4.0 μm or less is preferable from the viewpoint of aspect ratio and pattern collapse of the formed fine pattern.

  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 Resin (1))
Under a nitrogen stream, 8.6 g of cyclohexanone was placed in a three-necked flask and heated to 80 ° C. To this, 7.8 g of norbornane lactone methacrylate, 3.5 g of 3-hydroxyadamantyl methacrylate, 8.2 g of 2-methyl-2-adamantyl methacrylate, 2.5 g of cyclohexyl methacrylate, a polymerization initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) A solution prepared by dissolving 5 mol% in 79 g of cyclohexanone was added dropwise over 6 hours. After completion of dropping, the reaction was further carried out at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then added dropwise to a mixed solution of 700 ml of hexane / 300 ml of ethyl acetate over 20 minutes, and the precipitated powder was collected by filtration and dried to obtain 19 g of Resin (1). The weight average molecular weight of the obtained resin (1) was 10,000 in terms of standard polystyrene, and the dispersity (Mw / Mn) was 1.9.

  Other resins were synthesized using the same method. The weight average molecular weight was adjusted by changing the amount of the polymerization initiator.

  Tables 2 to 4 below show the monomers used in the synthesis of the resins (1) to (23) of the present invention and the resins (R1) to (R3) of the comparative examples, the molar ratio of repeating units corresponding to the monomers, and the weight Average molecular weight (Mw) and dispersity (Mw / Mn) are shown.

Examples 1 to 23 and Comparative Examples 1 to 7
<Resist preparation>
The components shown in Tables 5 to 6 below were dissolved in a solvent, and a solution with a solid content of 5% by mass was prepared for each, and this was filtered through a 0.1 μm polyethylene filter to prepare a positive resist composition. The prepared positive resist composition was evaluated by the following method, and the results are shown in Tables 5-6. About each component in a table | surface, ratio when using multiple is mass ratio.
In Tables 5 to 6, when the positive resist composition contains a surface hydrophobizing resin (HR), the addition form is marked as “addition”. When the positive resist composition does not contain a surface hydrophobic resin (HR) and a resist film is formed and then a top coat containing the surface hydrophobic resin (HR) is formed on the upper layer, the addition form is changed to “TC” ".

Image performance test (Exposure conditions (1) Normal dry exposure)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The positive resist composition prepared thereon was applied and baked at 130 ° C. for 60 seconds to form a 120 nm resist film. Using the obtained wafer ArF excimer laser scanner (manufactured by ASML, PAS5500 / 1100, NA0.75), the film was exposed through a 6% halftone mask with a 65 nm 1: 1 line and space pattern. Thereafter, heating was performed at 130 ° C. for 60 seconds, followed by development with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 30 seconds, rinsing with pure water, and spin drying to obtain a resist pattern.

(Exposure conditions (2) Normal immersion exposure)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The positive resist composition prepared thereon was applied and baked at 130 ° C. for 60 seconds to form a 120 nm resist film. The obtained wafer was exposed through a 6% halftone mask having a 65 nm 1: 1 line and space pattern using an ArF excimer laser immersion scanner (PAS5500 / 1250i, NA0.85, manufactured by ASML). Ultra pure water was used as the immersion liquid. Thereafter, heating was performed at 130 ° C. for 60 seconds, followed by development with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 30 seconds, rinsing with pure water, and spin drying to obtain a resist pattern.

(Exposure conditions (3) Dry double exposure)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The positive resist composition prepared thereon was applied and baked at 130 ° C. for 60 seconds to form a 120 nm resist film. Using the ArF excimer laser scanner (PAS5500 / 1100, manufactured by ASML, NA0.75), the obtained wafer is first exposed through a 6% halftone mask of a 60 nm space 180 nm line pattern, and the same as the first mask. In the pattern, the second exposure was performed by shifting the position of the mask by 120 nm so that the space was arranged between the space of the first exposure and the space. Thereafter, heating was performed at 130 ° C. for 60 seconds, followed by development with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 30 seconds, rinsing with pure water, and spin drying to obtain a resist pattern.

(Exposure condition (4) immersion double exposure)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The positive resist composition prepared thereon was applied and baked at 130 ° C. for 60 seconds to form a 120 nm resist film. Using the ArF excimer laser immersion scanner (ASML, PAS5500 / 1250i, NA0.85), the obtained wafer is first exposed through a 6% halftone mask with a 50 nm space, 150 nm line pattern, and then the first mask. In the same pattern, the second exposure was performed by shifting the position of the mask by 100 nm so that the space was arranged between the first exposure space and the space. Ultra pure water was used as the immersion liquid. Thereafter, heating was performed at 130 ° C. for 60 seconds, followed by development with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 30 seconds, rinsing with pure water, and spin drying to obtain a resist pattern.

When the addition form of the surface hydrophobizing resin (HR) was “TC”, the following operation was performed after forming the resist film.
<Formation method of top coat>
The surface hydrophobic resin (HR) shown in Tables 5 to 6 is dissolved in a solvent on the resist film, applied with a spin coater, and the wafer is heated and dried at 115 ° C. for 60 seconds to form a 0.05 μm top coat layer. It was. At this time, the top coat application unevenness was observed, and it was confirmed that it was uniformly applied without application unevenness.
Abbreviations for solvents are as follows.
SL-1; 2-ethylbutanol SL-2; perfluorobutyltetrahydrofuran

<Development defect evaluation>
Using a defect inspection device KLA2360 (trade name) manufactured by KLA-Tencor Corporation, the pixel size of the defect inspection device is set to 0.16 μm, and the threshold value is set to 20, and a random image is used for comparison. And the number of development defects per unit area was calculated by detecting the development defects extracted from the differences caused by the pixel unit overlap. A value of less than 0.5 was evaluated as ◯, a value of 0.5 to 0.8 was evaluated as Δ, and a value of 0.8 or more was evaluated as ×. A smaller value indicates better performance.

<Pattern shape>
The pattern shape was observed with a scanning microscope (Hitachi, Ltd. S-4800).

  The symbols in the table are as follows.

[Basic compounds]
TPI: 2,4,5-triphenylimidazole TPSA: triphenylsulfonium acetate DIA: 2,6-diisopropylaniline DCMA: dicyclohexylmethylamine TPA: tripentylamine TBAH: tetrabutylammonium hydroxide TMEA: tris (methoxyethoxyethyl) Amine PEA: N-phenyldiethanolamine TOA: Trioctylamine DBN: 1,5-diazabicyclo [4.3.0] non-5-ene PBI: 2-phenylbenzimidazole
DHA: N, N-dihexylaniline

[Surfactant]
W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)
W-4: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)
W-5: PF656 (manufactured by OMNOVA, fluorine-based)
W-6: PF6320 (manufactured by OMNOVA, fluorine-based)

〔solvent〕
A1: Propylene glycol monomethyl ether acetate A3: Cyclohexanone A4: γ-butyrolactone B1: Propylene glycol monomethyl ether B2: Ethyl lactate B3: Propylene carbonate

[Dissolution inhibitor compound]
LCB: t-butyl lithocholic acid

  From the results in Tables 5 to 6, it can be seen that the positive resist composition of the present invention has good development defect performance and pattern shape in normal exposure (dry exposure), liquid immersion exposure, and double exposure.

It is a schematic diagram which shows the state of the double exposure process in this invention.

Claims (8)

(A) a compound that generates an acid upon irradiation with an actinic ray or radiation,
(B) A resin having 1 to 20 mol% of a repeating unit represented by the following general formula (NGH-1) based on all repeating units in the resin, and having increased solubility in an alkali developer by the action of an acid and ( C) A positive resist composition comprising a compound that decomposes by the action of an acid to generate an acid.

In the general formula (NGH-1),
R _NGH1 represents a hydrogen atom or an alkyl group.
R _{NGH2 to} R _NGH4 each independently represents a hydrogen atom, an alkoxy group or a hydroxyl group. However, at least one of R _{NGH2 to} R _NGH4 represents a hydroxyl group.   The positive resist composition according to claim 1, further comprising a surface hydrophobizing resin.   A pattern forming method comprising: forming a resist film from the positive resist composition according to claim 1; and exposing and developing the resist film.   A pattern forming method comprising the steps of: forming a resist film with the positive resist composition according to claim 1; and subjecting the resist film to immersion exposure and development.   The method includes forming a resist film with the positive resist composition according to claim 1, forming a topcoat containing a surface hydrophobizing resin on the resist film, immersion exposure, and developing. A characteristic pattern forming method.   A pattern forming method comprising the steps of: forming a resist film from the positive resist composition according to claim 1; and double exposing and developing the resist film.   A pattern forming method comprising the steps of: forming a resist film from the positive resist composition according to claim 1; and subjecting the resist film to immersion double exposure and development.   A process comprising: forming a resist film with the positive resist composition according to claim 1; forming a topcoat containing a surface hydrophobic resin on the resist film; and performing immersion double exposure and development. The pattern formation method characterized by the above-mentioned.

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