KR101045251B1 - Positive resist composition and pattern formation method using the resist composition - Google Patents

Abstract

The present invention provides a positive resist composition having a wide exposure latitude, low PEB temperature dependency, and a large defocus latitude.

The composition contains a repeating unit having an alicyclic group in the (A1) side chain, a resin in which the dissolution rate in an alkali developer is increased by the action of an acid, and a repeating unit having a chain tertiary alkyl group in the (A2) side chain, It is a positive resist composition containing resin which the dissolution rate with respect to alkaline developing solution increases by the action of an acid, and (B) the compound which generate | occur | produces an acid by irradiation of actinic light or radiation.

Description

Positive resist composition and pattern formation method using the resist composition {POSITIVE RESIST COMPOSITION AND PATTERN FORMATION METHOD USING THE RESIST COMPOSITION}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to positive photoresist compositions for microfabrication such as semiconductor devices sensitive to far ultraviolet rays, and more particularly to positive photoresist compositions for far ultraviolet exposure.

In recent years, integrated circuits have been increasingly increasing in density, and in the manufacture of semiconductor substrates such as ultra-LSI, processing of ultrafine patterns having line widths of less than half microns has been required. In order to satisfy the necessity, the wavelength of use of an exposure apparatus used for photolithography has become shorter and it has recently been studied to use short wavelength excimer laser light (XeCl, KrF, ArF, etc.) among far ultraviolet rays.

There is a chemical amplification resist used for the pattern formation of lithography in this wavelength region.

In general, chemically-amplified resists can be broadly classified into three types: two-component, 2.5-component, and three-component systems. The two-component system is a combination of a compound that generates an acid by photolysis (hereinafter referred to as a photoacid generator) and a binder resin. The binder resin is a resin having a group (also called an acid-decomposable group) in the molecule that is decomposed by the action of an acid and increases the solubility of the resin in the alkaline developer. The 2.5 component system further contains a low molecular compound having an acid decomposable group in such a two component system. A three component system contains a photo-acid generator, alkali-soluble resin, and the said low molecular weight compound.

The chemically amplified resist is suitable for ultraviolet or far-infrared ray photoresist, but among them, the chemical amplification resist needs to correspond more to the characteristics required for use.

As a photoresist composition for ArF light sources, a resin in which an alicyclic hydrocarbon moiety is introduced for the purpose of imparting dry etching resistance has been proposed. The development in the tetramethylammonium hydroxide (TMAH) aqueous solution which has been used becomes difficult, or the phenomenon of the resist peeling from a board | substrate during development appears.

For this reason, introduction of the hydrophilic group into resin into which the alicyclic hydrocarbon site | part was introduce | transduced was examined variously.

Japanese Patent Laid-Open No. 9-73173 and Japanese Patent Laid-Open No. 10-161313 disclose alkali-soluble groups protected by a structure containing an alicyclic group and an acid containing a structural unit in which the alkali-soluble group is released by an acid and becomes alkali-soluble. Resist materials using sensitive compounds are described.

Japanese Laid-Open Patent Publication No. 2003-107710 discloses a resist composition containing a resin containing a repeating unit having two specific acid-decomposable groups as a composition in which etching surface roughness, roughness dependency, and pattern peeling are reduced.                         

Resin containing an acid-decomposable group used for the above photoresist for far-ultraviolet exposure generally contains an aliphatic cyclic hydrocarbon group in a molecule | numerator simultaneously. In the above technique, there are still insufficient points, and various improvements are desired.

For example, when using a wafer having a large aperture, it is known that the temperature fluctuation in heating (PEB) caused by a post-exposure hot plate or the like affects a pattern obtained, and it is desired that such a PEB temperature dependency is small.

In addition, improvement of characteristics such as exposure latitude and defocus latitude is desired.

It is an object of the present invention to have a wide exposure latitude, low PEB temperature dependency, and a large defocus latitude, which can be preferably used in ultra-microlithography processes such as the manufacture of ultra-LSI or high-capacity microchips or other photofabrication processes. It is to provide a positive resist composition.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining the structural material of a positive chemical amplification resist composition, the present inventors discovered that the objective of this invention was achieved by the following structure, and came to this invention.

(1) (A1) Resin which contains the repeating unit represented by following General formula (I), and the dissolution rate with respect to alkaline developing solution increases by the action of an acid,

(A2) Resin which contains the repeating unit represented by general formula (II), and the dissolution rate with respect to alkaline developing solution increases by the action of an acid, and                     

(B) The positive resist composition containing the compound which generate | occur | produces an acid by irradiation of actinic light or a radiation.

(In general formula (I), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG represents either of the following general formulas (pI) to (pV).

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates.

R <_12> -R <_16> respectively independently shows a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ and any one of R ₁₅ and R ₁₆ represent an alicyclic hydrocarbon group.

R ₁₇ to R ₂₁ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R ₁₇ to R ₂₁ represents an alicyclic hydrocarbon group. In addition, any one of R <_19> , R <_21> represents a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group.

R ₂₂ to R ₂₅ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R ₂₂ to R ₂₅ represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring)

(In General Formula (II), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group. BLG represents a chain tertiary alkyl group.)

(2) The positive resist composition as described in (1) in which at least one of the resins (A1) and (A2) contains a repeating unit represented by the following general formula (III).                     

(In General Formula (III), R ₃₀ represents a hydrogen atom or a methyl group.

R ₃₁ to R ₃₃ each independently represent a hydrogen atom, a hydroxy group, or an alkyl group, but at least one represents a hydroxy group)

(3) The positive resist composition as described in (2), wherein in the repeating unit represented by General Formula (III), two of R ₃₁ to R ₃₃ are hydroxy groups.

(4) In any one of (1)-(3), 1 or more of resin (A1) and (A2) further contains the repeating unit which has cyclohexane lactone, norbornane lactone, or adamantane lactone. Positive resist composition.

(5) The positive resist composition according to any one of (1) to (4), wherein in General Formula (I), A is a single bond and ALG is a group represented below.

(R ₂₆ and R ₂₇ each independently represent a linear or branched alkyl group having 1 to 4 carbon atoms)

Hereinafter, the component used for this invention is demonstrated in detail.

In addition, in description of group (atom group) in this specification, the description which is not describing substitution or unsubstitution includes what has a substituent with the thing which does not have a substituent. For example, an "alkyl group" means including not only an alkyl group (unsubstituted alkyl group) having no substituent but also an alkyl group (substituted alkyl group) having a substituent.

[1] resins, which increase the dissolution rate in alkaline developer by the action of acid

The composition of the present invention is a resin (acid-decomposable resin) in which the dissolution rate in an alkali developer is increased by the action of an acid, and a repeating unit represented by the general formula (I) which is decomposed by the action of an acid to generate an alkali soluble group. The action of an acid having a repeating unit represented by the general formula (II), which is decomposed by the action of an acid (resin (A1)) and an acid, which dissolves in an alkali developer by the action of an acid having an acid, and generates an alkali soluble group. It contains resin (resin (A2)) by which the dissolution rate with respect to alkaline developing solution increases.

First, resin (A1) is demonstrated.

Resin (A1) contains a repeating unit represented by the general formula (I) which is decomposed by the action of an acid to generate an alkali soluble group, and the resin (acid-decomposable resin) increases in dissolution rate in an alkaline developer by the action of an acid. )to be.

In general formula (I), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG is group containing the alicyclic hydrocarbon represented by said general formula (pI)-(pV).

The linking group of A is an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amido group, a sulfonamido group, a urethane group, or a combination of two or more groups selected from the group consisting of urea groups Indicates. As an alkylene group in said A, group represented by a following formula can be mentioned.

-[C (R _b ) (R _c )] _r-

In the formula, R _b and R _c represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group, or an alkoxy group, and both may be the same or different. The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group (preferably C1-C4) can be mentioned. As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom. r represents the integer of 1-10.

In formulas (pI) to (pV), R ₁₂ to R ₂₅ As an alkyl group in this, any of substituted or unsubstituted may be sufficient, and a C1-C4 linear or branched alkyl group is shown. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group and the like.

Further, other substituents of the alkyl group include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), acyl group, acyloxy group, cyano group, hydroxy group, carboxyl group, alkoxycarbonyl group And nitro groups can be enumerated.

The alicyclic hydrocarbon group or the alicyclic hydrocarbon group formed by Z and a carbon atom in R ₁₁ to R ₂₅ may be monocyclic or polycyclic. Specifically, the group which has a C5 or more monocyclo, bicyclo, tricyclo, tetracyclo structure, etc. can be mentioned. 6-30 are preferable and, as for the carbon number, 7-25 are especially preferable. These alicyclic hydrocarbon groups may have a substituent.

The structural example of an alicyclic site | part in an alicyclic hydrocarbon group is shown below.

In the present invention, preferred examples of the alicyclic moiety include an adamantyl group, noadamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclohexyl group, cycloheptyl group, A cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group can be mentioned. More preferably, they are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, a cyclododecanyl group, and a tricyclodecanyl group.

As a substituent of these alicyclic hydrocarbon groups, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxy group, and an alkoxycarbonyl group are mentioned.

The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably a substituent selected from the group consisting of methyl group, ethyl group, propyl group and isopropyl group.

As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned.

As said alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, can be mentioned.

Moreover, since the profile stability (SEM tolerance) at the time of observing the obtained profile with a scanning electron microscope is favorable, the repeating unit which A is a single bond in general formula (I) and ALG is shown below is especially preferable. Do.                     

R ₂₆ and R ₂₇ each independently represent a linear or branched alkyl group having 1 to 4 carbon atoms.

Hereinafter, the specific example of the monomer corresponded to the repeating unit represented by general formula (I) is shown.

Next, resin (A2) is demonstrated.

Resin (A2) is a resin (acid-decomposable resin) in which the dissolution rate in an alkaline developer is increased by the action of an acid having a repeating unit represented by the general formula (II) which is decomposed by the action of an acid to generate an alkali-soluble group. .

R and A in general formula (II) are the same as R and A in general formula (I), respectively.

BLG represents a chain tertiary alkyl group. For example, it is represented by -C (Ra) (Rb) (Rc). Ra, Rb and Rc are each independently a linear or branched alkyl group (generally 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, for example, methyl, ethyl, linear or branched). Vapor phase propyl group, linear or branched butyl group, linear or branched pentyl group).                     

The alkyl group as Ra, Rb and Rc may have a substituent. As a preferable substituent, a halogen atom, a hydroxyl group, and an alkoxy group (preferably C1-C10, More preferably, C1-C5) can be mentioned.

Although the specific example of the repeating unit represented by general formula (II) is listed below, it is not limited to these.

Resin (A1) and (A2) may contain repeating units other than the said essential repeating unit. Hereinafter, the repeating unit which is preferable to contain other than the said essential repeating unit is demonstrated.

At least one of the resins (A1) and (A2) preferably contains a repeating unit represented by the general formula (III) in view of the exposure margin, the expansion of the defocus latitude (DOF) of the isolated line, and the reduction of the density dependency.

In General Formula (III), R ₃₀ represents a hydrogen atom or a methyl group.

R ₃₁ to R ₃₃ each independently represent a hydrogen atom, a hydroxy group, or an alkyl group, but at least one represents a hydroxy group.

In the repeating unit represented by General Formula (III), two of R ₃₁ to R ₃₃ are particularly preferably hydroxy groups in this respect.

Although the specific example of the repeating unit represented by general formula (III) is listed below, it is not limited to these.

In addition, it is preferable that at least one of resin (A1) and (A2) contains the repeating unit which has alicyclic lactone structure from the point which further reduces pattern collapse and roughness dependency.

As a repeating unit which has alicyclic lactone structure, the repeating unit which has cyclohexane lactone, norbornane lactone, or adamantane lactone can be mentioned, for example.

For example, as a repeating unit which has cyclohexane lactone, the repeating unit which has group represented by the following general formula (V-1) and (V-2), and the repeating unit which has norbornane lactone are the following general formula (V-3) The repeating unit which has a group represented by the following formula (V-4), and the repeating unit which has adamantane lactone can mention the repeating unit which has group represented by following General formula (VI).

In General Formulas (V-1) to (V-4), each of R _1b to R _5b independently represents a hydrogen atom or an alkyl group, cycloalkyl group, or alkenyl group which may have a substituent. Two of R _1b to R _5b may be bonded to each other to form a ring.

In general formula (V-1)-(V-4), a linear and branched alkyl group may be mentioned as an alkyl group in R <_1b> -R <_5b> , and you may have a substituent.

As a linear or branched alkyl group, a C1-C12 linear or branched alkyl group is preferable, More preferably, it is a C1-C10 linear or branched alkyl group, More preferably, a methyl group, an ethyl group, and a propyl group , Isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group and decyl group.

As a cycloalkyl group in R <_1b> -R <_5b> , C3-C8 things, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group, are preferable.

As an alkenyl group in R <_1b> -R <_5b> , C2-C6 things, such as a vinyl group, a propenyl group, butenyl group, and a hexenyl group, are preferable.

_Examples of the ring formed by bonding of two of R _1b to R _5b include a 3-8 membered ring such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring.

In addition, R _1b to R _5b in General Formulas (V-1) to (V-4) may be bonded to any one of the carbon atoms constituting the cyclic skeleton.

Moreover, as a preferable substituent which the said alkyl group, a cycloalkyl group, and an alkenyl group may have, a C1-C4 alkoxy group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), and a C2-C5 axle A practical group, a C2-C5 acyloxy group, a cyano group, a hydroxyl group, a carboxy group, a C2-C5 alkoxycarbonyl group, a nitro group, etc. can be mentioned.

As a repeating unit which has group represented by general formula (V-1)-(V-4), the repeating unit represented by the following general formula (V), etc. can be mentioned.

In general formula (V), R <_b0> represents a hydrogen atom, a halogen atom, or a C1-C4 substituted or unsubstituted alkyl group. As a preferable substituent which the alkyl group of R <_b0> may have, what was illustrated previously as a preferable substituent which the alkyl group as R < _1b in the said General Formula (V-1)-(V-4) may have is mentioned.

_Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R _b0 is preferably a hydrogen atom.

A _b represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group or a divalent group in combination thereof.

V represents a group represented by any one of General Formulas (V-1) to (V-4). Examples of divalent groups combined in A _{b include those} of the following formulae.

In the above formula, R _ab , R _bb represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group, or an alkoxy group, and both may be the same or different.

The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and a C1-C4 alkoxy group can be mentioned.

As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned.

Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom.

r1 is an integer of 1-10, Preferably the integer of 1-4 is represented. m represents an integer of 1 to 3, preferably 1 or 2.

Although the specific example of the repeating unit represented by general formula (V) is listed below, the content of this invention is not limited to these.

As a repeating unit which has adamantane lactone, the repeating unit represented by the following general formula (VI) can be enumerated.

In general formula (VI), A <_6> represents single or a combination of 2 or more groups chosen from the group which consists of a single bond, an alkylene group, a cycloalkylene group, an ether group, a thioether group, a carbonyl group, and an ester group.

R _6a represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyano group, or a halogen atom.

In general formula (VI), the group represented by a following formula can be mentioned as an alkylene group of A <_6> .

-[C (Rnf) (Rng)] r-

In the formula, Rnf and Rng represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group and an alkoxy group, and both may be the same or different. The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned. As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, can be mentioned. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom. r is an integer of 1-10.

In general formula (VI), a C3-C10 thing is mentioned as a cycloalkylene group of A <_6> , A cyclopentylene group, a cyclohexylene group, a cyclooctylene group, etc. can be mentioned.

The bridged alicyclic ring containing Z ₆ may have a substituent. Examples of the substituent include a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms), an alkoxycarbonyl group (preferably having 1 to 5 carbon atoms), an acyl group (for example, a formyl group, a benzoyl group), an acyloxy group (e. g., propyl carbonyl group, benzoyl group), the alkyl group (preferably having 1 to 4) (such as a -CONHSO ₂ CH _3), carboxy group, a hydroxy group, an alkylsulfonyl nilsul sulfamoyl group are exemplified. In addition, the alkyl group as a substituent may be further substituted with a hydroxyl group, a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms) or the like.

In general formula (VI), the oxygen atom of the ester group couple | bonded with A <_6> may be couple | bonded with any position of the carbon atom which comprises the Z ₆ containing cyclic bridge alicyclic ring structure.

Although the specific example of the repeating unit represented by general formula (VI) is listed below, it is not limited to these.

In addition, resin (A1) and (A2) may further contain the repeating unit which has a lactone structure represented by the following general formula (IV).

In General Formula (IV), R _1a represents a hydrogen atom or a methyl group.

W ₁ represents a single bond or a combination of two or more groups selected from the group consisting of a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, and an ester group.

R _a1 , R _b1 , R _c1 , R _d1 and R _e1 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m and n represent the integer of 0-3 each independently, and m + n is 2 or more and 6 or less.

Examples of the alkyl group having 1 to 4 carbon atoms of R _a1 to R _e1 include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group and tert-butyl group.

In the formula (IV), the alkylene groups of W ₁ may be exemplified groups represented by the following formula.

[C (Rf) (Rg)] r _1-

In the formula, Rf and Rg represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxy group and an alkoxy group, and both may be the same or different.

The alkyl group is preferably a lower alkyl group such as methyl group, ethyl group, propyl group, isopropyl group or butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned.

As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, can be mentioned.

Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom.

r ₁ is an integer of 1-10.

Examples of the other substituent in the alkyl group include a carboxyl group, acyloxy group, cyano group, alkyl group, substituted alkyl group, halogen atom, hydroxy group, alkoxy group, substituted alkoxy group, acetylamido group, alkoxycarbonyl group and acyl group.

Here, as an alkyl group, lower alkyl groups, such as a methyl group, an ethyl group, a propyl group, isopropyl group, a butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclopentyl group, are mentioned. As a substituent of a substituted alkyl group, a hydroxyl group, a halogen atom, and an alkoxy group can be mentioned. As a substituent of a substituted alkoxy group, an alkoxy group etc. can be mentioned. As an alkoxy group, C1-C4 things, such as a methoxy group, an ethoxy group, a propoxy group, butoxy group, are mentioned. As acyloxy group, an acetoxy group etc. are mentioned. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom and iodine atom.

Hereinafter, although the specific example of the monomer corresponded to the repeating unit represented by General formula (IV) is shown, it is not limited to these.

In addition to the repeating units, the resins (A1) and (A2) may be used in various repeating units for the purpose of adjusting dry etching resistance, standard developer aptitude, substrate adhesion, resist profile, and resolution, heat resistance and sensitivity, which are general necessary characteristics of the resist. It may contain.

Although the repeating structural unit corresponded to the following monomer can be enumerated as such a repeating unit, It is not limited to these.

Thereby, the performance required for acid-decomposable resins, in particular

(1) solubility in coating solvents,

(2) film forming property (glass transition temperature),

(3) alkali developability,

(4) membrane reduction (selection of hydrophilic, hydrophobic or alkali-soluble groups),

(5) adhesion to the substrate of the unexposed portion,

(6) dry etching resistance

Fine adjustment of the back and the like becomes possible.

Examples of such monomers include compounds having one addition polymerizable unsaturated bond selected from acrylates, methacrylates, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and the like. Can be enumerated.

Specifically, the following monomers can be enumerated.

Acrylates (preferably alkyl acrylates having 1-10 carbon atoms):

Methyl acrylate, ethyl acrylate, propyl acrylate, amyl acrylate, cyclohexyl acrylate, ethylhexyl acrylate, octyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate, 2,2-dimethylhydrate Hydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimetholpropane monoacrylate, pentaerythritol monoacrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate and the like.

Methacrylates (preferably alkyl methacrylates having 1 to 10 carbon atoms in the alkyl group):

Methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimetholpropane monomethacrylate, pentaerythritol monomethacrylate, Furfuryl methacrylate, tetrahydrofurfuryl methacrylate, and the like.

Allyl compound:

Allyl esters (for example, allyl acetate, allyl caproate, allyl caprylate, allyllaurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, and the like), allyloxyethanol and the like.

Vinyl ethers:

Alkyl vinyl ethers (e.g., hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethyl hexyl vinyl ether, methoxy ethyl vinyl ether, ethoxy ethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl) Vinyl ether, 2-ethylbutyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl Vinyl ether).

Vinyl esters:

Vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valerate, vinyl caproate, vinyl chloro acetate, vinyl dichloro acetate, vinyl methoxy acetate, vinyl butoxy acetate, vinyl aceto acetate, vinyl lactate, Vinyl-β-phenylbutyrate, vinylcyclohexylcarboxylate and the like.

Dialkylitaconates:

Dimethyl itaconate, diethyl itaconate, dibutyl itaconate and the like.

Dialkyl fumarates or monoalkyl fumarates:

Dibutyl fumarate and the like.

In addition, crotonic acid, itaconic acid, maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, maleilonitrile and the like.

In addition, as long as it is an addition polymerizable unsaturated compound which can copolymerize with the monomer corresponded to the said various repeating units, you may copolymerize.

In the resin, the molar ratio of each repeating unit is suitably set in order to adjust dry etching resistance, standard developer aptitude, substrate adhesion, resist profile and resist, resolution, heat resistance, sensitivity, and the like.

As for the content rate of the repeating unit represented by General formula (I) in resin (A1), 15-60 mol% is preferable in all the repeating units, More preferably, it is 18-55 mol%, More preferably, it is 20-50 mol %to be.

In resin (A1), 5-50 mol% is preferable in the total repeating unit of each resin, and, as for the content rate of the repeating unit represented by General formula (III), More preferably, it is 10-45 mol%, More preferably, 15-40 mol%.

In the resin (A1), the content of the repeating unit having an alicyclic lactone structure is preferably 5 to 60 mol%, more preferably 10 to 55 mol%, still more preferably 15 to 50 mol% in the total repeating units. .

In resin (A1), as for content of the repeating unit which has a lactone structure in the side chain represented by following General formula (IV), 5-60 mol% is preferable in all the repeating units, More preferably, it is 10-50 mol%, More preferably, it is 15-45 mol%.

As for the content rate of the repeating unit represented by General formula (II) in resin (A2), 10-80 mol% is preferable in all the repeating units, More preferably, it is 15-75 mol%, More preferably, it is 20-70 mol %to be.

In the resin (A2), the content of the repeating unit represented by the general formula (III) is preferably 2 to 40 mol%, more preferably 5 to 35 mol%, even more preferably in the total repeating units of each resin. 8-30 mol%.

In the resin (A2), the content of the repeating unit having an alicyclic lactone structure is preferably 10 to 50 mol%, more preferably 15 to 45 mol%, even more preferably 20 to 40 mol% of all the repeating units. .                     

In resin (A2), as for content of the repeating unit which has a lactone structure in the side chain represented by following General formula (IV), 10-50 mol% is preferable in all the repeating units, More preferably, it is 15-45 mol%, More preferably, it is 20-40 mol%.

When the composition of this invention is for ArF exposure, it is preferable that resin does not have an aromatic group from a transparency point with respect to ArF light.

The resin used in the present invention can be synthesized by conventional methods (such as radical polymerization). For example, as a general synthetic method, monomer species are injected into the reaction vessel in a batch or during the reaction, and as necessary, ethers such as a reaction solvent such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, Ketones, such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents, such as ethyl acetate, or various monomers, such as propylene glycol monomethyl ether acetate, mentioned later, are made to melt | dissolve and make it uniform, and nitrogen, argon, etc. It heats as needed in inert gas atmosphere of the, and superposition | polymerization is started using a commercial radical initiator (azo initiator, peroxide, etc.). An initiator is added or divided and added as desired, and after completion of the reaction, it is added to a solvent to recover a desired polymer by a method such as powder or solid recovery. The reaction concentration is 20% by mass or more, preferably 30% by mass or more, and more preferably 40% by mass or more. Reaction temperature is 10-150 degreeC, Preferably it is 30-120 degreeC, More preferably, it is 50-100 degreeC.

The weight average molecular weight of the resins (A1) and (A2) is preferably 3,000 to 100,000, more preferably 4,000 to 50,000, and even more preferably 5,000 to 30,000, in terms of polystyrene in terms of the GPC method. That is, the weight average molecular weight is preferably 3,000 or more in terms of heat resistance and dry etching resistance, and 100,000 or less is preferable in view of developability and film forming properties.

Moreover, the range of 1.3-4.0 of the dispersion degree (Mw / Mn) of resin (A1) and (A2) is preferable, More preferably, it is 1.4-3.8, More preferably, it is 1.5-3.5.

In the resist composition of the present invention, the blending amount in the whole composition of the resins (A1) and (A2) is preferably from 40 to 99.99 mass% in the total resist solid content, more preferably from 50 to 99.97 mass%.

As addition ratio of resin (A1) and resin (A2), Preferably it is 95 / 5-40 / 60, More preferably, 90 / 10-50 / 50, as resin (A1) / resin (A2) (mass ratio), More preferably, it is 80/20-60/40.

[2] (B) A compound which generates acid by irradiation of actinic light or radiation (photoacid generator)

Examples of the compound (photoacid generator) that generates an acid by irradiation of actinic light or radiation used in the present invention include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photochromic agent for pigments, a photochromic agent, a microresist, and the like. Activity of known light used (ultraviolet radiation of 400-200 nm, far ultraviolet rays, particularly preferably g-ray, h-ray, i-ray, KrF excimer laser light), ArF excimer laser light, electron beam, X-ray, molecular beam or ion beam. The compound which generate | occur | produces an acid by irradiation of light or a radiation, and a mixture thereof can be selected suitably, and can be used.

For example, a diazonium salt, a phosphonium salt, a sulfonium salt, an iodonium salt, an imido sulfonate, an oxime sulfonate, a diazo disulfone, a disulfone, o-nitrobenzyl sulfonate can be mentioned.

Especially preferably, it is a sulfonium salt, The sulfonium salt which has a triaryl sulfonium salt, a penacyl sulfonium salt, and a 2-oxoalkyl group is the most preferable.

Further, compounds in which an acid or a group which generates an acid by irradiation of these actinic rays or radiation is introduced into the main chain or the side chain of the polymer, such as US Patent No. 3,849,137, German Patent No. 3,914,407, and Japanese Patent Application Publication No. 63-26653. No. 55-164824, No. 62-69263, No. 63-146038, No. 63-163452, No. 62-153853 and No. 63-146029 Compounds can be used.

In addition, a compound which generates an acid by light described in US Pat. No. 3,779,778, EP 126,712 or the like can also be used.

Among the compounds which are decomposed by irradiation with actinic light or radiation which may be used in combination and generate an acid, compounds represented by the following general formulas (ZI), (ZII) and (ZIII) can be enumerated.

In General Formula (ZI), R ₂₀₁ , R _202, and R ₂₀₃ each independently represent an organic group.

X ⁻ represents a nonnucleophilic anion.

Examples of non-nucleophilic anions of X ⁻ include sulfonic acid anion, carboxylic acid anion, bis (alkylsulfonyl) imido anion, tris (alkylsulfonyl) methyl anion, and the like.

A non-nucleophilic anion is an anion with very low ability to generate a nucleophilic reaction, and is an anion which can suppress the degradation over time by the intramolecular nucleophilic reaction. This improves the time stability of the resist.

Examples of the sulfonic acid anion include alkyl sulfonic acid anion, aryl sulfonic acid anion, camphor sulfonic acid anion and the like.

Examples of the carboxylic acid anion include alkyl carboxylic acid anions, arylcarboxylic acid anions, aralkyl carboxylic acid anions, and the like.

The alkyl group in the alkyl sulfonic acid anion is preferably an alkyl group having 1 to 30 carbon atoms, such as a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group and neophene. Tyl 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.

As an aryl group in an aryl sulfonic acid anion, C6-C14 aryl groups, such as a phenyl group, a tolyl group, a naphthyl group, etc. are mentioned preferably.                     

The alkyl group and aryl group in the said alkyl sulfonic acid anion and aryl sulfonic acid anion may have a substituent.

As a substituent, a halogen atom, an alkyl group, an alkoxy group, an alkylthio group, etc. are mentioned, for example.

Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom, iodine atom and the like.

As the alkyl group, for example, preferably an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, a 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, etc. Can be enumerated.

As an alkoxy group, Preferably, a C1-C5 alkoxy group, for example, a methoxy group, an ethoxy group, a propoxy group, butoxy group etc. can be mentioned.

As the alkylthio group, for example, preferably an alkylthio group having 1 to 20 carbon atoms, such as methylthio group, ethylthio group, propylthio group, isopropylthio group, n-butylthio group, isobutylthio group, sec-butyl Thio group, pentylthio group, neopentylthio group, hexylthio group, heptylthio group, octylthio group, nonylthio group, decylthio group, undecylthio group, dodecylthio group, tridecylthio group, tetradecylthio group, Pentadecylthio group, hexadecylthio group, heptadecylthio group, octadecylthio group, nonadecylthio group, eicosylthio group, etc. can be mentioned. In addition, the alkyl group, the alkoxy group and the alkylthio group may be further substituted with a halogen atom (preferably a fluorine atom).

As an alkyl group in an alkylcarboxylic acid anion, the thing similar to the alkyl group in an alkyl sulfonic acid anion can be mentioned.

Examples of the aryl group in the arylcarboxylic acid anion include the same ones as the aryl group in the aryl sulfonic acid anion.

Aralkyl groups in the aralkylcarboxylic acid anion are preferably aralkyl groups having 6 to 12 carbon atoms, such as benzyl group, phenethyl group, naphthylmethyl group, naphthylethyl group and the like.

The aralkyl group, aryl group and aralkyl group in the alkyl carboxylic acid anion, the arylcarboxylic acid anion and the aralkyl carboxylic acid anion may have a substituent, and as the substituent, for example, the same halogen atom as in the arylsulfonic acid anion , An alkyl group, an alkoxy group, an alkylthio group, and the like.

The alkyl group in the bis (alkylsulfonyl) imido anion and the tris (alkylsulfonyl) methyl anion is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, Isobutyl group, sec-butyl group, pentyl group, neopentyl group and the like. These alkyl groups may have a substituent and a halogen atom, an alkoxy group, an alkylthio group etc. can be mentioned as a substituent, for example.

Other non-nucleophilic anions include, for example, phosphorus fluoride, boron fluoride, antimony fluoride and the like.                     

Examples of non-nucleophilic anions of X ⁻ include alkanesulfonic acid anion in which the α-position of the sulfonic acid is substituted with a fluorine atom, an aryl sulfonic acid anion substituted with a fluorine atom or a group having a fluorine atom, and a bis (alkylsulfonyl) imido in which an alkyl group is substituted with a fluorine atom Tris (alkylsulfonyl) methyl anion in which an anion and an alkyl group are substituted with a fluorine atom is preferable, particularly preferably a perfluoroalkanesulfonic anion having 1 to 8 carbon atoms, most preferably a nonafluorobutanesulfonic acid anion and a perfluoro Octane sulfonic acid anion.

The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1 to 30, preferably 1 to 20.

In addition, two of R ₂₀₁ to R _{203 may be} bonded to each other to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amido bond, or a carbonyl group.

Examples of the group formed by bonding of two of R ₂₀₁ to R ₂₀₃ include an alkylene group (eg, butylene group, pentylene group).

As a specific example of the organic group as R <_201> , R <_202> and R <_203> , the corresponding group in compound (Z1-1), (Z1-2), (Z1-3) mentioned later can be mentioned.

Moreover, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, at least one of the following general formula (ZI) the compound of R ₂₀₁ ~ R ₂₀₃ represented by a may be a compound having a binding structure with at least one of addition of a compound represented by formula (ZI) R ₂₀₁ ~ R ₂₀₃ good.

As more preferable (ZI) component, the compound (Z1-1), (Z1-2), and (Z1-3) demonstrated below can be mentioned.

Compound (Z1-1) is a triarylsulfonium compound in which each of R ₂₀₁ to R _{203 in the} formula (ZI) is an aryl group, that is, a compound having triarylsulfonium as a cation.

As an aryl group of a triarylsulfonium cation, a phenyl group and a naphthyl group are preferable, More preferably, it is a phenyl group. The three aryl groups of the triarylsulfonium cation may be the same or different.

Each aryl group may have an alkyl group (for example, C1-C15), an alkoxy group (for example, C1-C15), a halogen atom, a hydroxy group, and a phenylthio group as a substituent. Preferred substituents are a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, a linear, branched or cyclic alkoxy group having 1 to 12 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms and 1 to 4 carbon atoms. It is an alkoxy group. The substituent may be substituted by any of three aryl groups and may be substituted by all three. Moreover, it is preferable that the substituent is substituted by the p-position of an aryl group.

Next, the compound (Z1-2) will be described.

Compound (Z1-2) is a compound in the case where R ₂₀₁ to R ₂₀₃ in Formula (ZI) each independently represent an organic group containing no aromatic ring. Here, an aromatic ring also includes the aromatic ring containing a hetero atom.

The organic group which does not contain an aromatic ring as R ₂₀₁ to R ₂₀₃ is generally 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

R ₂₀₁ to R ₂₀₃ are each independently preferably an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, a vinyl group, and more preferably a linear, branched, cyclic 2-oxoalkyl group, or alkoxycarbonyl Methyl groups, most preferably linear, branched 2-oxoalkyl groups.

The alkyl group as R ₂₀₁ to R ₂₀₃ may be any of linear, branched or cyclic, preferably a linear or branched alkyl group having 1 to 10 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, pentyl group). ), And a C3-C10 cyclic alkyl group (for example, cyclopentyl group, cyclohexyl group, norbornyl group) can be mentioned.

The 2-oxoalkyl group as R ₂₀₁ to R ₂₀₃ may be any of linear, branched or cyclic, and preferably groups having> C═O at the 2-position of the alkyl group.

As an alkoxy group in the alkoxycarbonylmethyl group as R <_201> -R <_203> , Preferably, the C1-C5 alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, butoxy group, a pentoxy group) can be mentioned. .

R ₂₀₁ to R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, 1 to 5 carbon atoms), a hydroxy group, a cyano group, and a nitro group.

Two of R ₂₀₁ to R _{203 may be} bonded to each other to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amido bond, or a carbonyl group. Examples of the group formed by bonding of two of R ₂₀₁ to R ₂₀₃ include an alkylene group (eg, butylene group, pentylene group).

A compound (Z1-3) is a compound represented by the following general formula (Z1-3), and is a compound which has a penacylsulfonium salt structure.

R _1c to R _5c each independently represent a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom.

R _6c and R _7c each independently represent a hydrogen atom, an alkyl group or an aryl group.

R _x and R _y each independently represent an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group or a vinyl group.

Two or more of R _1c to R _7c , and R _x and R _y may be bonded to each other to form a ring structure, and the ring structure may contain an oxygen atom, a sulfur atom, an ester bond or an amido bond.

Z _c ^- represents a non-nucleophilic anion and may be the same as the non-nucleophilic anion of X ⁻ in General Formula (ZI) or (ZII).

The alkyl group as R _1c to R _5c may be any of linear, pulverized and cyclic alkyl groups, for example, an alkyl group having 1 to 10 carbon atoms, preferably a linear and crushed alkyl group having 1 to 5 carbon atoms (eg, a methyl group, Ethyl groups, linear or branched propyl groups, linear or branched butyl groups, or linear or branched pentyl groups, and C3-C8 cyclic alkyl groups (e.g., cyclopentyl groups, cyclohexyl groups) have.

The alkoxy group as R _1c to R _5c may be any linear, branched or cyclic alkoxy group, for example, a C 1-10 alkoxy group, preferably a C 1-5 straight and branched alkoxy group (e.g., Methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group, cyclic alkoxy group having 3 to 8 carbon atoms (e.g. cyclopentyloxy group, cyclohex) Siloxy group) can be enumerated.

Preferably, any one of R _1c to R _5c is a linear, branched, cyclic alkyl group or a linear, branched or cyclic alkoxy group, and more preferably, the sum of the carbon numbers of R _1c to R _5c is 2 to 15. . Thereby, solvent solubility improves more and generation | occurrence | production of particle | grains is suppressed at the time of storage.

_Examples of the alkyl group as R _6c and R _{7c include the} same alkyl groups as R _1c to R _5c . As an aryl group, a C6-C14 aryl group (for example, a phenyl group) can be mentioned, for example.

Alkyl groups as R _x and R _y may be the same as the alkyl groups as R _1c to R _5c .

2-oxoalkyl groups may enumerate groups having> C═O at the 2-position of the alkyl group as R _1c to R _5c .

Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _1c to R _5c .

Examples of the group formed by bonding of R _x and R _y include a butylene group and a pentylene group.

In General Formulas (ZII) and (ZIII), R ₂₀₄ to R ₂₀₇ each independently represent an aryl group which may have a substituent or an alkyl group which may have a substituent.

The aryl group of R ₂₀₄ ~ R ₂₀₇ may be a phenyl group, a naphthyl group, more preferably is a phenyl group.

The alkyl group as R ₂₀₄ to R ₂₀₇ may be any linear, branched or cyclic alkyl group, and preferably a linear or branched alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pen). And a cyclic alkyl group having 3 to 10 carbon atoms (eg, cyclopentyl group, cyclohexyl group, norbornyl group).

Examples of the substituent which R ₂₀₄ to R ₂₀₇ may have include an alkyl group (e.g., 1 to 15 carbon atoms), an aryl group (e.g., 6 to 15 carbon atoms), an alkoxy group (e.g., 1 to 15 carbon atoms), and a halogen. Atom, a hydroxyl group, a phenylthio group, etc. can be mentioned.

X <^-> represents a non-nucleophilic anion, and can mention the same thing as the non-nucleophilic anion of X <^-> in general formula (ZI) or (ZII).

Examples of particularly preferable compounds among compounds which decompose upon irradiation with actinic light or radiation which may be used in combination and generate an acid are listed below.

The addition amount of a photo-acid generator is used in 0.001-30 mass% normally on the basis of solid content in a composition, Preferably it is 0.3-20 mass%, More preferably, it is used in 0.5-10 mass%. That is, the addition amount of the photoacid generator is preferably 0.001% by mass or more in terms of sensitivity, and 30% by mass or less is preferable in terms of good light absorption of the resist, good profile, and process (especially baking) margin.

[3] additives, other

The positive resist composition of the present invention may further contain a surfactant, an organic basic compound, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer, a photosensitizer and a compound for promoting solubility in a developer, as necessary.

(C) surfactant

The positive resist composition of the present invention contains a surfactant, preferably a fluorine-based and / or silicon-based surfactant.

The positive resist composition of the present invention preferably contains any one or two or more of a fluorine-based surfactant, a silicon-based surfactant, and a surfactant containing both a fluorine atom and a silicon atom.

When the positive resist composition of the present invention contains the acid-decomposable resin and the surfactant, it is effective when the line width of the pattern is even thinner, and the development defect is further improved.

As these surfactants, for example, JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, JP-A-62-170950, JP-A-63-34540, and Japanese Patent Publications No. 7-230165, No. 8-62834, No. 9-54432, No. 9-5988, No. 5,405,720, No. 5,360,692, No. 5,529,881, No. The surfactants of 5,296,330, 5,436,098, 5,576,143, 5,294,511 and 5,824,451 can be enumerated, and the following commercially available surfactant can also be used as it is.

As commercially available surfactants that can be used, for example, EFtop EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florad FC430, FC431 (manufactured by Sumitomo 3M Ltd.), Megafac F171, F173, F176, F189, R08 ( Dainippon Ink and Chemicals, Inc.), Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), Troysol S-366 (manufactured by Troy Chemical Corp.) Fluorine-based surfactants or silicone-based surfactants. In addition, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) may also be used as the silicone-based surfactant.

The compounding quantity of surfactant is 0.001-2 mass% normally based on solid content in the composition of this invention, Preferably it is 0.01-1 mass%. These surfactants may be added alone or in combination of several.

As surfactants which can be used other than the above, specifically, polyoxyethylene alkyl ethers, such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, and polyoxy Polyoxyethylene alkylallyl ethers such as ethylene octyl phenol ether and polyoxyethylene nonyl phenol ether, polyoxyethylene polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostea Sorbitan fatty acid esters such as latex, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan Monostearate, polyoxyethylene sorbitan triole Agent, polyoxyethylene can be exemplified such as sorbitan tristearate, etc., polyoxyethylene sorbitan fatty acid non-ionic surfactants such as esters.

The compounding quantity of these other surfactant is 2 mass parts or less normally per 100 mass parts of solid content in the composition of this invention, Preferably it is 1 mass part or less.

(D) an organic basic compound

Preferred organic basic compounds which can be used in the present invention are compounds which are more basic than phenol. Especially, a nitrogen-containing organic basic compound is preferable, and the structure represented, for example by following (A)-(E) is mentioned.

Where R ²⁵⁰ , R ²⁵¹ and R ²⁵² each independently represent a hydrogen atom, an alkyl group of 1 to 6 carbon atoms, an aminoalkyl group of 1 to 6 carbon atoms, a hydroxyalkyl group of 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group of 6 to 20 carbon atoms, Here, R ²⁵¹ and R ²⁵² may combine with each other to form a ring.

In formula, R <^253> , R <^254> , R <^255> and R <^256> represent a C1-C6 alkyl group each independently.

More preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms in different chemical environments in one molecule, particularly preferably compounds containing both substituted or unsubstituted amino groups and ring structures containing nitrogen atoms or alkylamino groups It is a compound which has. Preferred embodiments include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazole, substituted or unsubstituted Substituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted pipepe Razine, substituted or unsubstituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine, and the like. Preferred substituents are amino group, aminoalkyl group, alkylamino group, aminoaryl group, arylamino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxy group, cyano group.

As a preferred embodiment of the nitrogen-containing basic compound, guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine , 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2 -Amino-6-methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) pi Ferridine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, pyra Sol, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-dia Minopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazole , N-aminomorpholine, N- (2-aminoethyl) morpholine, 1,5-diazabicyclo [4.3.0] nona-5-ene, 1,8-diazabicyclo [5.4.0] undeca -7-ene, 1,4-diazabicyclo [2.2.2] octane, 2,4,5-triphenylimidazole, N-methylmorpholine, N-ethylmorpholine, N-hydroxyethylmorpholine , Tertiary morpholine derivatives such as N-benzyl morpholine, cyclohexyl morpholinoethylthiourea (CHMETU), and hindered amines described in Japanese Patent Application Laid-Open No. 11-52575 (for example, those described in the above publication). ), But are not limited to these.

Particularly preferred embodiments are 1,5-diazabicyclo [4.3.0] nona-5-ene, 1,8-diazabicyclo [5.4.0] undeca-7-ene, 1,4-diazabicyclo [ 2.2.2] tertiary such as octane, 4-dimethylaminopyridine, hexamethylenetetramine, 4,4-dimethylimidazoline, pyrroles, pyrazoles, imidazoles, pyridazines, pyrimidines and CHMETU Hindered amines, such as morpholines and bis (1,2,2,6,6-pentamethyl-4- piperidyl) sebacate, etc. can be mentioned.

Among them, 1,5-diazabicyclo [4.3.0] nona-5-ene and 1,8-diazabicyclo [5. 4.0] undec-7-ene, 1,4-diazabicyclo [2.2.2] octane, 4-dimethylaminopyridine, hexamethylenetetramine, CHMETU, bis (1,2,2,6,6-pentamethyl 4-piperidyl) sebacate is preferred.

These organic basic compounds are used individually or in combination of 2 or more types. The usage-amount of an organic basic compound is 0.001-10 mass% normally with respect to solid content of the whole composition of the resist composition of this invention, Preferably it is 0.01-5 mass%. That is, 0.001 mass% or more is preferable at the point which acquires sufficient addition effect, and 10 mass% or less is preferable at the point of a sensitivity or developability of a non-exposed part.

The positive resist composition of this invention is melt | dissolved in the solvent which melt | dissolves each said component, and is apply | coated on a support body. The solvent used here is ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl Acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), ethylene carbonate, toluene, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, methyl methoxy Propionate, ethylethoxypropionate, methylpyruvate, ethylpyruvate, propylpyruvate, N, N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferred. These solvents are used alone or in combination.

Among the above, preferred solvents include propylene glycol monomethyl ether acetate, 2-heptanone, γ-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, Propylene glycol monoethyl ether, ethylene carbonate, butyl acetate, methyl lactate, ethyl lactate, methyl methoxy propionate, ethyl ethoxy propionate, N-methylpyrrolidone and tetrahydrofuran.

Such a positive resist composition of the present invention is applied onto a substrate to form a thin film. As for the film thickness of this coating film, 0.2-1.2 micrometers is preferable.

Examples of the substrate that can be used include a BareSi substrate, an SOG substrate, or a substrate having an inorganic antireflection film described below.

In addition, a commercially available inorganic or organic anti-reflective coating can be used as necessary.

As the anti-reflection film, an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, α-silicon, etc., and an organic film type made of a light absorber and a polymer material may be used. The former requires equipment such as a vacuum deposition apparatus, a CVD apparatus, a sputtering apparatus, etc. to form the film. As the organic antireflection film, for example, a condensation product of a diphenylamine derivative described in Japanese Patent Publication No. Hei 7-69611 and a formaldehyde-modified melamine resin, an alkali-soluble resin and a light absorber, and maleic anhydride described in U.S. Patent No. 5,294,680 A reactant of a copolymer with a diamine light absorber, a resin binder as described in Japanese Patent Application Laid-Open No. 6-118631, a methirolmelamine-based thermal crosslinking agent, a carboxylic acid group as described in Japanese Patent Application Laid-Open No. 6-118656, an epoxy group, and An acrylic resin antireflection film having a light absorber in the same molecule, consisting of methirolmelamine described in JP-A-8-87115 and a benzophenone-based light absorber, and low molecular weight in the polyvinyl alcohol resin of JP-A-8-179509 The thing which added the light absorber etc. are mentioned.

As the organic antireflection film, DUV-30 series, DUV-40 series, ARC 25, AC-2, AC-3, AR 19, AR 20, etc., manufactured by Brewer Science, can be used.

The resist liquid is applied onto a substrate (e.g., silicon / silicon dioxide coating) used in the manufacture of a precision integrated circuit device (if necessary, on a substrate on which the antireflection film is formed) by a suitable coating method such as a spinner, a coater, or the like. Subsequently, a good resist pattern can be obtained by exposing through a predetermined mask, baking and developing. As exposure light here, Preferably it is wavelength light of 150-250 nm. Specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), an X-ray, an electron beam, etc. are mentioned.

As an alkaline developer, inorganic alkalis, such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia water, 1st amines, such as ethylamine and n-propylamine, diethylamine, di-n-butylamine, etc. Tertiary ammonium salts such as tertiary amines, triethylamine, methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, and tetraethylammonium hydroxide Alkaline aqueous solutions (usually 0.1-20 mass%), such as cyclic amines, such as a pyrrole and a piperidine, can be used.

Moreover, alcohol and surfactant can be added to the alkaline aqueous solution in an appropriate amount.

Example

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example.

Synthesis Example (1) Synthesis of Resin (1)

2-adamantyl-2-propyl methacrylate, 3,5-dihydroxy-1-adamantyl acrylate, norbornanelactone acrylate are injected at a ratio of 40/20/40 (molar ratio), Propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 (mass ratio) was dissolved, and 450 g of a solution having a solid content concentration of 22% was prepared. Wako Pure Chemical Industries, Ltd. 1.2 mol of V-601 of the product was added, and this was dripped at 50 g of mixed solutions of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 (mass ratio) heated at 100 degreeC over 6 hours in nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized with 5 L of a mixed solvent of hexane / ethyl acetate = 9/1 (mass ratio), and the precipitated white powder was collected by filtration to recover resin (1) as a target product.                     

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 39/21/40. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 9,200, and dispersion degree was 2.1.

Hereinafter, resins (2) to (10) were synthesized in the same manner as in Synthesis Example (1) (repeating units a to d are sequentially from the left side of the structural formula).

The structure of the said resin (1)-(10) is shown below.

Synthesis Example (2) Synthesis of Resin (2-1)

t-butyl methacrylate, 3,5-dihydroxy-1-adamantyl acrylate and norbornanelactone acrylate were injected at a ratio of 40/20/40 (molar ratio), and propylene glycol monomethyl ether acetate It dissolved in / propylene glycol monomethyl ether = 60/40, and 450g of solution of 22% of solid content concentration was prepared. Wako Pure Chemical Industries, Ltd. 6 mol of V-601 of the product was added, and this was dripped at 50 g of mixed solutions of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 (mass ratio) heated at 80 degreeC over 6 hours in nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was stirred for 2 hours. After the completion of the reaction, the reaction solution was cooled to room temperature, crystallized with 5 L of a mixed solvent of hexane / ethyl acetate = 9/1 (mass ratio), and the precipitated white powder was collected by filtration to recover the desired resin (2-1). .

The composition ratio (molar ratio) of the polymer determined from ¹³ C-NMR was a / b / c = 41/20/39. In addition, the weight average molecular weight of the standard polystyrene conversion calculated | required by GPC measurement was 9,900, and dispersion degree was 1.8.

Hereinafter, resins (2-2) to (2-10) were synthesized in the same manner as in Synthesis Example (2).                     

In addition, the structures of the resins (2-1) to (2-10) are shown below.

Examples 1-14 and Comparative Examples 1-3

Preparation and Evaluation of Positive Resist Composition

As shown in Table 3, the resin (the amount shown in Table 3), the photoacid generator (the amount shown in Table 3), the organic basic compound (4 mg) and the surfactant (10 mg) synthesized in the above synthesis example were blended, and the solid content 11 After melt | dissolving with the solvent shown in Table 3 so that it may become mass%, it filtered through the 0.1 micrometer microfilter, and produced the positive resist composition of Examples 1-14 and Comparative Examples 1-3. In addition, the ratio at the time of using plural about each component in Table 3 is mass ratio.

In addition, resin R1 used for the comparative example 1 is resin (1) synthesize | combined according to the synthesis example (1) of Unexamined-Japanese-Patent No. 2003-107710. The molar ratio of the following repeating units is 30/12/19/39 in order from the left of the repeating units, and the weight average molecular weight is 11,600.

The symbol about each component shown in Table 3 is as follows.

[Surfactants]

1: Megafac F176 (Dainippon Ink and Chemicals, Inc.) (fluorine-based)                     

2: Megafac R08 (Dainippon Ink and Chemicals, Inc.) (fluorine and silicon-based)

3: polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.)

4: polyoxyethylene nonyl phenyl ether

5: Troysol S-366 (manufactured by Troy Chemical)

.

[Basic compound]

1: N, N-dihydroxyethylaniline

2: N, N-dibutylaniline

3: trioctylamine

4: triphenylimidazole

5: antipyrine

6: 2,6-diisopropylaniline

7: 1,5-diazabicyclo [4.3.0] -5-nonene (DBN)

.

[solvent]

S1: Propylene Glycol Monomethyl Ether Acetate

S2: Propylene Glycol Monomethyl Ether

S3: cyclohexanone

(Assessment Methods)

First of all, Brewer Science Inc. ARC-29 of the product was coated on a silicon wafer using a spin coater at 85 nm, dried, and then the positive photoresist composition obtained thereon was applied, dried at a temperature (SB) shown in Table 3 for 90 seconds, and then 300 nm positive. A resist film was formed, and it was exposed with ArF excimer laser (wavelength: 193 nm, NA: 0.6 ArF stepper manufactured by ISI Co., Ltd.) in a contact hole pattern of 1/2 pitch while varying the exposure amount and focus. The post-exposure heat treatment was performed at the temperature (PEB) shown in Table 3 for 90 seconds, developed with a 2.38% by mass tetramethylammonium hydroxide aqueous solution, rinsed with distilled water to obtain a resist pattern profile.

The resist pattern of the silicon wafer thus obtained was observed with a scanning microscope, and the resist was evaluated as follows.

[Exposure margin]

The exposure dose at which the contact hole pattern of the mask size 180 nm (360 nm pitch) is reproduced at 150 nm is the optimum exposure dose (E ₀ ), the maximum exposure dose that reproduces the line width of 150 nm ± 10% is set to E ₁ , and the minimum exposure dose is set to E ₂ . The exposure margin (%) is expressed by the following formula.

(E ₁ -E ₂ ) / E ₀ │ × 100

[Defocus Latitude (DOF)]

The defocus latitude indicated the dimensions of the contact hole mask pattern of 150 nm in an allowable width (μm) in the range of ± 10%.

[PEB temperature dependence]

The exposed contact pattern of mask size 150 nm is exposed at the exposure amount which reproduces the isolated contact hole of mask size 150 nm at 130 nm, and post-exposure heating (PEB) is +2 degreeC and -2 degreeC with respect to the temperature shown in Table 3. two temperatures (e.g., when the PEB temperature shown in Table 3 in 100 ℃, 98 ℃ and 102 ℃) is performed at, and length-measuring a contact hole pattern obtained, respectively, were determined for their diameter L ₁ and L _2. PEB temperature dependence was defined as a change in diameter per 1 ° C of PEB temperature change, and was calculated by the following equation.

PEB temperature dependence (nm / ℃) = | L ₁ -L ₂ | / 4

As can be seen from the results in Table 3, the positive resist composition of the present invention has a wide exposure latitude, a small PEB temperature dependency, and a wide defocus latitude, indicating that various performances are excellent.

 The present invention can provide a positive resist composition having a wide exposure latitude, low PEB temperature dependency, and a large defocus latitude. The positive resist composition of the present invention can be preferably used for microfabrication using far ultraviolet light, especially ArF excimer laser light.

Claims (6)

(A1) Resin containing the repeating unit represented by following General formula (I), and the dissolution rate with respect to alkaline developing solution increases by the action of an acid, (A2) Resin which contains the repeating unit represented by general formula (II), and the dissolution rate with respect to alkaline developing solution increases by the action of an acid, and (B) contains a compound which generates an acid by irradiation of actinic light or radiation, At least one of the resins (A1) and (A2) further comprises a repeating unit having a cyclohexane lactone, norbornane lactone or adamantane lactone.

(In general formula (I), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG represents either of the following general formulas (pI) to (pV).

Wherein R ₁₁ represents a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group or sec-butyl group, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with carbon atoms Indicates. R <_12> -R <_16> respectively independently shows a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group. Provided that at least one of R ₁₂ to R ₁₄ and any one of R ₁₅ and R ₁₆ represent an alicyclic hydrocarbon group. R ₁₇ to R ₂₁ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R ₁₇ to R ₂₁ represents an alicyclic hydrocarbon group. In addition, any one of R <_19> , R <_21> represents a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group. R ₂₂ to R ₂₅ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R ₂₂ to R ₂₅ represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring)

(In General Formula (II), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group. BLG represents a chain tertiary alkyl group.) The positive resist composition according to claim 1, wherein at least one of the resins (A1) and (A2) contains a repeating unit represented by the following general formula (III).

(In General Formula (III), R ₃₀ represents a hydrogen atom or a methyl group. R ₃₁ to R ₃₃ each independently represent a hydrogen atom, a hydroxy group, or an alkyl group, but at least one represents a hydroxy group) The positive resist composition according to claim 2, wherein in the repeating unit represented by the general formula (III), two of R ₃₁ to R ₃₃ are hydroxy groups. delete The positive resist composition according to any one of claims 1 to 3, wherein in formula (I), A is a single bond and ALG is a group represented below.

(R ₂₆ and R ₂₇ each independently represent a linear or branched alkyl group having 1 to 4 carbon atoms) A pattern forming method comprising the step of forming a resist film with the positive resist composition according to claim 1 and the fixing for exposing and developing the resist film.