JP2001109153A - Positive type resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a chemical amplification type positive type photoresist composition having high sensitivity, ensuring improved edge roughness of a pattern and giving an excellent resist pattern profile. SOLUTION: The positive type resist composition contains a compound which generates an acid when irradiated with active light or radiation and a resin containing an alkali-soluble group protected with at least one specified alicyclic hydrocarbon-containing partial structure, having <=5% monomer content based on the entire pattern area by gel permeation chromatography(GPC) and having the rate of dissolution in an alkali developing solution increased by the action of the acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive resist composition used in an ultra microlithography process such as the production of an ultra LSI or a high-capacity micro chip, or other photofabrication processes. More specifically, the present invention relates to a positive resist composition which has excellent profile and high sensitivity, in which edge roughness is eliminated.

[0002]

2. Description of the Related Art In recent years, the degree of integration of integrated circuits has been increasing more and more, and in the manufacture of semiconductor substrates such as VLSIs, processing of ultrafine patterns having a line width of less than half a micron is required. It has become In order to satisfy the need, the wavelength used in an exposure apparatus used for photolithography is becoming shorter and shorter, and now it is considered to use excimer laser light (XeCl, KrF, ArF, etc.) having a short wavelength among far ultraviolet rays. Up to now.
A chemically amplified resist is used for forming a pattern in lithography in this wavelength region.

In general, chemically amplified resists can be broadly classified into three types: so-called two-component, 2.5-component and three-component resists. The two-component system combines 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 in its molecule a group (also referred to as an acid-decomposable group) that decomposes under the action of an acid to increase the solubility of the resin in an alkaline developer. The 2.5-component system further contains a low-molecular compound having an acid-decomposable group in such a two-component system. The three-component system contains a photoacid generator, an alkali-soluble resin, and the above low molecular compound.

The above-mentioned chemically amplified resist is suitable for a photoresist for irradiating ultraviolet rays or far ultraviolet rays, but among them, it is necessary to further meet the required characteristics in use. As a photoresist composition for an ArF light source, a resin having an alicyclic hydrocarbon moiety introduced therein for the purpose of imparting dry etching resistance has been proposed. However, such a phenomenon that the development with an aqueous solution of tetramethylammonium hydroxide (hereinafter referred to as TMAH), which has been widely used as a resist developing solution in the past, becomes difficult, and the resist is peeled off from the substrate during the development. Can be seen. In response to such a resist hydrophobization, measures such as mixing an organic solvent such as isopropyl alcohol with a developing solution have been studied, and although tentative results have been obtained, the swelling of the resist film and the process become complicated. This does not necessarily mean that the problem has been solved. In the approach of improving the resist, many measures have been taken to supplement various hydrophobic alicyclic hydrocarbon sites by introducing a hydrophilic group.

JP-A-10-10739 discloses an energy-sensitive resist containing a polymer obtained by polymerizing a monomer having an alicyclic structure such as a norbornene ring in its main chain, maleic anhydride, and a monomer having a carboxyl group. Materials are disclosed. JP-A-10-111569 discloses a radiation-sensitive resin composition containing a resin having an alicyclic skeleton in the main chain and a radiation-sensitive acid generator. JP-A-11-109632 describes that a resin containing a polar group-containing alicyclic functional group and an acid-decomposable group is used for a radiation-sensitive material.

As described above, a resin containing an acid-decomposable group used for a photoresist for exposure to far ultraviolet rays generally contains an aliphatic cyclic hydrocarbon group in the molecule at the same time. For this reason, the resin becomes hydrophobic, and there is a problem caused by the hydrophobicity. Various means for improving the above have been studied, but the above techniques still have many insufficient points, and improvements are desired.

In recent years, with the demand for miniaturization of semiconductor chips, the design pattern of the fine semiconductor is 0.13 to 0.13.
It reaches a fine area of 0.35 μm. However,
These compositions have a problem that the resolution of the pattern is hindered by factors such as the edge roughness of the line pattern. Here, the edge roughness refers to the top and bottom edges of a resist line pattern that fluctuate irregularly in a direction perpendicular to the line direction due to the characteristics of the resist. Means that the edge looks uneven.

[0008]

As described above, in the known technique of the conventional photoresist composition, roughness is observed at the edge of the pattern, and a stable pattern cannot be obtained. Therefore, further improvement is desired. Was. Accordingly, it is an object of the present invention to provide a chemically amplified positive photoresist composition having high sensitivity, improved pattern edge roughness, and capable of obtaining an excellent resist pattern profile.

[0009]

Means for Solving the Problems As a result of intensive studies on the constituent materials of the positive type chemically amplified resist composition, the present inventors have achieved the object of the present invention by using a specific acid-decomposable resin. This led to the present invention. That is,
The above object is achieved by the following constitutions. (1) (A) It contains an alkali-soluble group protected by at least one of partial structures containing an alicyclic hydrocarbon represented by the following general formulas (pI) to (pVI), and contains a monomer component A resin whose amount is not more than 5% of the total pattern area of gel permeation chromatography (GPC), and whose dissolution rate in an alkali developing solution is increased by the action of an acid;

[0010]

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Wherein R ₁₁ is a methyl group, an ethyl group, n
-Represents a 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 a carbon atom. R _{12 to} R ₁₆ each independently represent a group having 1 to 4 carbon atoms;
It represents a linear or branched alkyl group or an alicyclic hydrocarbon group, provided that at least one of R _{12 to} R ₁₄ , or any of R ₁₅ and R ₁₆ represents an alicyclic hydrocarbon group. R
_{17 to} R ₂₁ each independently represent a hydrogen atom, a linear or branched alkyl group or an alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or an alicyclic hydrocarbon group having 1 to 4 carbon atoms. R _{22 to} R ₂₅ are each independently
It represents a linear or branched alkyl group or an alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{22 to} R ₂₅ represents an alicyclic hydrocarbon group. (B) A positive resist composition comprising a compound that generates an acid upon irradiation with actinic rays or radiation.

(2) The resin of the above (A) is a resin obtained by dropping a reaction solution containing a monomer and a radical initiator into a reaction solvent or a reaction solution containing a monomer to cause a polymerization reaction. The positive resist composition according to the above (1), which is characterized in that: (3) The resin of (A) is a resin obtained by dividing and charging a radical initiator into a reaction solution containing a monomer over 30 minutes to 8 hours and polymerizing the same. The positive resist composition according to (1) above. (4) The resin (A) is obtained by heating a reaction solution containing a monomer and a radical initiator to cause a polymerization reaction, and then re-adding the radical initiator thereto and heating it again to cause a polymerization reaction. (1) characterized in that the resin is a cured resin.
The positive resist composition according to any one of (1) to (3). (5) After completion of the polymerization reaction of the resin (A), the reaction solution is treated with water, at least one of alcohols, water / alcohols, water / ethers, water / ketones, water / amides, water / Esters or lactones, water / nitrile and at least one liquid selected from the group
The positive resist composition according to any one of the above (1) to (4), which is a resin recovered as a powder.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, components used in the present invention will be described in detail. [1] (A) A resin whose dissolution rate in an alkali developer is increased by the action of an acid (also referred to as “acid-decomposable resin”). Hereinafter, each component of the acid-decomposable resin of the present invention will be described. In the general formulas (pI) to (pVI), R _{12 to} R
The alkyl group in ₂₅ represents a linear or branched alkyl group having 1 to 4 carbon atoms, which may be substituted or unsubstituted. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group,
Isopropyl group, n-butyl group, isobutyl group, sec
-Butyl group, t-butyl group and the like. Further, as the further substituent of the alkyl group, an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom,
(Bromine atom, iodine atom), acyl group, acyloxy group, cyano group, hydroxyl group, carboxy group, alkoxycarbonyl group, nitro group and the like.

The alicyclic hydrocarbon group represented by R _{11 to} R _{25 or} the alicyclic hydrocarbon group formed by Z and a carbon atom may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The number of carbon atoms is preferably from 6 to 30, particularly preferably from 7 to 25. These alicyclic hydrocarbon groups may have a substituent. Below, the structural example of an alicyclic part among alicyclic hydrocarbon groups is shown.

[0015]

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[0016]

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[0017]

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In the present invention, preferred examples of the alicyclic moiety include an adamantyl group, a noradamantyl group, a decalin residue, a tricyclodecanyl group, a tetracyclododecanyl group, a norbornyl group, a cedrol group, and a cyclohexyl group. , Cycloheptyl group, cyclooctyl group,
Examples thereof include a cyclodecanyl group and a cyclododecanyl group. More preferred 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, and a cyclododecanyl group.

Examples of the substituent of these alicyclic hydrocarbon groups include an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group and an alkoxycarbonyl group. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group and a butyl group, and more preferably a methyl group, an ethyl group, a propyl group, and a substituent selected from the group consisting of an isopropyl group. Represent. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom and an alkoxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group.

Formulas (pI) to (pV) in the above resins
Examples of the alkali-soluble group protected by the structure represented by I) include various groups known in this technical field. Specific examples include a carboxylic acid group, a sulfonic acid group, a phenol group, and a thiol group, and a carboxylic acid group and a sulfonic acid group are preferable. The alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI) in the above resin is preferably the following general formula (pVI)
Groups represented by I) to (pXI).

[0021]

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Here, R _{11 to} R ₂₅ and Z are the same as defined above. In the above resin, as the repeating unit having an alkali-soluble group protected by the structure represented by any of formulas (pI) to (pVI), a repeating unit represented by the following formula (pA) is preferable.

[0023]

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Here, R represents a hydrogen atom, a halogen atom or a substituted or unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of Rs may be the same or different. A is singly or two or more selected from the group consisting of a single bond, an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, and a urea group. Represents a combination of groups. Ra represents any one of the above formulas (pI) to (pVI). Hereinafter, specific examples of the monomer corresponding to the repeating unit represented by the general formula (pA) are shown.

[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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In the above resin, the compounds represented by the general formula (pI) to
In addition to the repeating unit having an alkali-soluble group protected by the structure represented by (pVI), another repeating unit may be included. Such another repeating unit is preferably a repeating unit represented by the following general formula (AI).

[0032]

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R has the same meaning as described above. B is a halogen atom, a cyano group, a group decomposed by the action of an acid, -C (=
O) represents _{-YAR c9} or -COOR _c11 . Y: oxygen atom, sulfur atom, -NH-, -NHSO2-,
Divalent bonding group selected from _{-NHSO2NH-, R c9: -COOH, -COOR} c10 (. R c10 those having the same meaning as R _c11, and representing the following lactone structure), - C
N, a hydroxyl group, an alkoxy group which may have a substituent,
_{-CO-NH-R c11, -CO} -NH-SO 2 -R c11
Alternatively, it represents the following lactone structure.

R _c11 : an alkyl group which may have a substituent, a cyclic hydrocarbon group which may have a substituent, A: a single bond, an alkylene group, a substituted alkylene group, an ether group, a thioether group, Represents a single group selected from the group consisting of a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, and a urea group, or a combination of two or more groups.

[0035]

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Ra to Re each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms which may have a substituent. m and n are each independently 0 to 3
And m + n is 2 or more and 6 or less. The group decomposed by the action of the acid is preferably -C (=
O) a group represented by -X ₁ -R0. Here, R0 is a tertiary alkyl group such as a t-butyl group, a t-amyl group, an isobornyl group, a 1-ethoxyethyl group, a 1-butoxyethyl group, a 1-isobutoxyethyl group, a 1-cyclohexyloxyethyl group. A 1-alkoxyethyl group such as a group, 1
Examples thereof include an alkoxymethyl group such as a -methoxymethyl group and a 1-ethoxymethyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a trialkylsilyl group, and a 3-oxocyclohexyl group. X ₁ represents an oxygen atom, a sulfur _{atom, -NH -, - HNSO 2 -} , - NHSO 2
Represents HN-, preferably an oxygen atom.

The alkyl group has 1 to 10 carbon atoms.
Linear or branched alkyl groups are preferred, more preferably a linear or branched alkyl group having 1 to 6 carbon atoms, even more preferably methyl, ethyl, propyl, isopropyl, n -Butyl group, isobutyl group, sec-butyl group and t-butyl group.

The above-mentioned cyclic hydrocarbon group is, for example, a cyclic alkyl group, a bridged hydrocarbon, and is a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a boronyl group, an isobornyl group, a tricyclodecanyl group, Cyclopentenyl group, nobornane epoxy group,
Menthyl, isomenthyl, neomenthyl, tetracyclododecanyl and the like can be mentioned.

As the alkoxy group, a methoxy group,
C1-C1 such as ethoxy, propoxy and butoxy groups
Four things can be mentioned.

Further substituents in the above alkyl group, cyclic alkyl group and alkoxy group include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group and an acyloxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group. Examples thereof include an acetoxy group.

The alkylene group and the substituted alkylene group represented by A in the above formulas (AI) and (pA) include the following groups. -[C (Rf) (Rg)] r- wherein Rf, Rg: a hydrogen atom, an alkyl group, a substituted alkyl group,
Represents a halogen atom, a hydroxyl group, or an alkoxy group; they may be the same or different; and the alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably a methyl group. Represents a substituent selected from the group consisting of a group, an ethyl group, a propyl group, and an isopropyl group. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom and an alkoxy group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.
Individuals can be mentioned. r represents an integer of 1 to 10. In the above, a chlorine atom as the halogen atom,
Examples thereof include a bromine atom, a fluorine atom, and an iodine atom. B is preferably an acid-decomposable group or a group represented by -COOR _C9 (lactone structure).

The acid-decomposable resin according to the present invention has a structure represented by the general formulas (pI) to (pVI) added to a copolymer component such as the repeating unit represented by the general formula (AI). It preferably contains an acid-decomposable group other than the protected alkali-soluble group. As such an acid-decomposable group that can be used in combination, a group represented by -C (= O) -OR0 is preferable. Preferred examples of the structures represented by the general formulas (pI) to (pVI) are, in particular, 2-alkyl-2-adamantane and the above-mentioned specific examples (5) which are acid-decomposable alicyclic monomers. 8) is preferred. Here, the alkyl group preferably has 1 to 4 carbon atoms.

The acid-decomposable resin further has the following general formula (III-
It is preferable to contain repeating structural units represented by a) to (III-d). Thereby, the problem due to the hydrophobicity of the resist composition can be improved.

[0044]

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In the above formulas (III-a) to (III-d), R₁Is
It has the same meaning as R in the general formula (pA). R_Five~ R₁₂Is each
Each independently a hydrogen atom or an optionally substituted
Represents a kill group. R has a hydrogen atom or a substituent
Alkyl group, cyclic alkyl group, aryl
Represents an aralkyl group or an aralkyl group. m represents an integer of 1 to 10
You. X represents a single bond or an optionally substituted substituent;
Alkylene group, cyclic alkylene group, arylene group or
Represents an ether group, a thioether group, a carbonyl group,
Ter group, amide group, sulfonamide group, urethane group,
Single or selected from the group consisting of urea groups
At least two or more of these groups are combined to form an acid
Represents a divalent group that does not decompose. Z is a single bond, A
Ter group, ester group, amide group, alkylene group, or
It represents a divalent group obtained by combining these. R₁₃Is a single bond,
Alkylene group, arylene group, or a combination thereof
Represents a divalent group. R_FifteenIs an alkylene group, arylene
Represents a group or a divalent group obtained by combining these groups. R₁₄Is
Optionally substituted alkyl group, cyclic alkyl
Represents an aryl group or an aralkyl group. R ₁₆Is hydrogen
An atom or an alkyl which may have a substituent
Group, cyclic alkyl group, alkenyl group, aryl group or
Represents an aralkyl group. A is any of the following functional groups
Represents

[0046]

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In the general formulas (III-a) to (III-d), R
The alkyl group of _{3 to} R ₁₀ , R, R ₁₂ , and R ₁₄ may be linear or branched, and may have a substituent.
As a linear or branched alkyl group, one having 1 carbon atom
To 12, more preferably 1 to 1 carbon atoms.
0, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group,
Preferred examples thereof include a sec-butyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. Examples of the cyclic alkyl group represented by R, R ₁₂ and R ₁₄ include those having 3 to 30 carbon atoms, and specifically, a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornyl group, a boronyl group, Examples thereof include a tricyclodecanyl group, a dicyclopentenyl group, a nobornane epoxy group, a menthyl group, an isomenthyl group, a neomenthyl group, a tetracyclododecanyl group, and a steroid residue.

The aryl group represented by R, R ₁₂ and R ₁₄ has 6 to 20 carbon atoms, and may have a substituent. Specific examples include a phenyl group, a tolyl group, and a naphthyl group. Examples of the aralkyl group represented by R, R ₁₂ and R ₁₄ include those having 7 to 20 carbon atoms and may have a substituent. Specifically, a benzyl group, a phenethyl group,
And a cumyl group. Examples of the alkenyl group for R ₁₄ include an alkenyl group having 2 to 6 carbon atoms, specifically, a vinyl group, a propenyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, a cyclopentenyl group, a cyclohexenyl group, 3-oxocyclohexenyl group, 3-
An oxocyclopentenyl group, a 3-oxoindenyl group and the like can be mentioned. Among these, the cyclic alkenyl group may contain an oxygen atom.

As the linking group X, an alkylene group, a cyclic alkylene group, an arylene group or an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group which may have a substituent. A group selected from the group consisting of urea groups, or a combination of at least two or more of these groups;
Examples include divalent groups that do not decompose under the action of an acid.

Z is a single bond, an ether group, an ester group,
An amide group, an alkylene group, or a combination thereof
Represents a valence group. R ₁₁ represents a single bond, an alkylene group, an arylene group, or a divalent group obtained by combining these. R
₁₃ represents an alkylene group, an arylene group, or a divalent group obtained by combining them. In X, R ₁₁ and R ₁₃ , examples of the arylene group include those having 6 to 10 carbon atoms, which may have a substituent. Specific examples include a phenylene group, a tolylene group, and a naphthylene group. Examples of the cyclic alkylene group for X include those in which the above-mentioned cyclic alkyl group is divalent. As the alkylene group for X, Z, R ₁₁ and R ₁₃ , specific examples of the linking group X having the same meaning as that of A in the general formula (pA) are shown below, but the content of the present invention is not limited thereto. Not something.

[0051]

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Further substituents in the above alkyl group, cyclic alkyl group, alkenyl group, aryl group, aralkyl group, alkylene group, cyclic alkylene group and arylene group include carboxyl group, acyloxy group, cyano group,
Alkyl group, substituted alkyl group, halogen atom, hydroxyl group,
Examples include an alkoxy group, an acetylamide group, an alkoxycarbonyl group, and an acyl group. Here, examples of the alkyl group include lower alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclopentyl group. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom and an alkoxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. Examples of the acyloxy group include an acetoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

Hereinafter, as a specific example of the structure of the side chain in the general formula (III-b), the structure of the side chain except for X is shown below.
It is not limited to these.

[0054]

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Hereinafter, specific examples of the monomer corresponding to the repeating structural unit represented by formula (III-c) will be shown, but it should not be construed that the invention is limited thereto.

[0056]

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[0057]

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[0058]

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Hereinafter, specific examples of the repeating structural unit represented by formula (III-d) will be shown, but it should not be construed that the invention is limited thereto.

[0060]

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[0061]

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[0062]

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In the general formula (III-b), R _{3 to} R ₁₀ are preferably a hydrogen atom or a methyl group. R is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m is 1
To 6 are preferable. In the general formula (III-c), R ₁₁ is a single bond, a methylene group, an ethylene group, a propylene group,
An alkylene group such as a butylene group is preferable. As R ₁₂ , an alkyl group having 1 to 10 carbon atoms such as a methyl group and an ethyl group, a cycloalkyl group such as a cyclopropyl group, a cyclohexyl group, and a camphor residue, a naphthyl group, a naphthyl A methyl group is preferred. Z is a single bond, an ether bond, an ester bond,
An alkylene group having 1 to 6 carbon atoms or a combination thereof is preferable, and a single bond or an ester bond is more preferable. In the general formula (III-d), R ₁₃ is preferably an alkylene group having 1 to 4 carbon atoms. As R ₁₄ , an alkyl group having 1 to 8 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a neopentyl group, an octyl group, a cyclohexyl group, and an adamantyl which may have a substituent. Group, norbornyl group, boronyl group,
An isobornyl group, a menthyl group, a morpholino group, a 4-oxocyclohexyl group, and a phenyl group, a toluyl group, a mesityl group, a naphthyl group, and a camphor residue which may have a substituent are preferable. As these further substituents, a halogen atom such as a fluorine atom, an alkoxy group having 1 to 4 carbon atoms and the like are preferable.

Among the general formulas (III-a) to (III-d),
The repeating structural unit represented by (III-b) and the general formula (III-d) is preferable.

The acid-decomposable resin as the component (A) is, in addition to the above-mentioned repeating structural units, dry etching resistance, suitability for a standard developing solution, substrate adhesion, resist profile, and general necessary properties of a resist. Various repeating structural units can be contained for the purpose of adjusting resolution, heat resistance, sensitivity and the like.

Examples of such a repeating structural unit include, but are not limited to, repeating structural units corresponding to the following monomers. Thereby, the performance required for the acid-decomposable resin, in particular, (1) solubility in a coating solvent, (2) film-forming property (glass transition point),
Fine adjustment of (3) alkali developability, (4) film loss (hydrophobicity, selection of alkali-soluble group), (5) adhesion of unexposed portion to substrate, (6) dry etching resistance, etc. becomes possible. . As such monomers, for example, acrylates, methacrylates, acrylamides,
Examples thereof include compounds having one addition-polymerizable unsaturated bond selected from methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and the like.

Specific examples include the following monomers. Acrylic esters (preferably alkyl acrylate having an alkyl group having 1 to 10 carbon atoms): methyl acrylate, ethyl acrylate, propyl acrylate, amyl acrylate, cyclohexyl acrylate, ethylhexyl acrylate, octyl acrylate, acrylic Acid-t-octyl, chloroethyl acrylate, 2-hydroxyethyl acrylate 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate,
Trimethylolpropane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate,
Methoxybenzyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate and the like.

Methacrylic esters (preferably alkyl methacrylate having an alkyl group having 1 to 10 carbon atoms): methyl methacrylate, ethyl methacrylate,
Propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate,
Cyclohexyl methacrylate, benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, penta Erythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate and the like.

Acrylamides: acrylamide, N-
Alkyl acrylamide (the alkyl group has 1 carbon atom
And 10 such as methyl, ethyl, propyl, butyl, t-butyl, heptyl, octyl, cyclohexyl, and hydroxyethyl. ), N, N-dialkylacrylamide (alkyl group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, butyl group, isobutyl group, ethylhexyl group,
A cyclohexyl group, etc.), N-hydroxyethyl-
N-methylacrylamide, N-2-acetamidoethyl-N-acetylacrylamide and the like.

Methacrylamides: methacrylamide,
N-alkyl methacrylamide (an alkyl group having 1 to 10 carbon atoms, such as a methyl group, an ethyl group,
Butyl group, ethylhexyl group, hydroxyethyl group, cyclohexyl group, etc.), N, N-dialkylmethacrylamide (alkyl group includes ethyl group, propyl group, butyl group, etc.), N-hydroxyethyl-N-
Methyl methacrylamide and the like.

Allyl compounds: allyl esters (eg, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, etc.), allyloxyethanol etc.

Vinyl ethers: alkyl vinyl ethers (eg, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether,
-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 and the like.

Vinyl esters: vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxy acetate, vinyl butoxy acetate, vinyl Acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinylcyclohexylcarboxylate and the like.

Dialkyl itaconates: dimethyl itaconate, diethyl itaconate, dibutyl itaconate and the like. Dialkyl esters or monoalkyl esters of fumaric acid; dibutyl fumarate;

Others crotonic acid, itaconic acid, maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, maleilenitrile and the like.

In addition, as long as it is an addition-polymerizable unsaturated compound copolymerizable with a monomer corresponding to the above-mentioned various repeating structural units, it may be copolymerized.

In the acid-decomposable resin, the molar ratio of each repeating structural unit depends on the dry etching resistance of the resist, the suitability for a standard developing solution, the substrate adhesion, the resist profile, and the resolving power, heat resistance, which is a general required performance of the resist. It is set as appropriate to adjust properties, sensitivity, and the like.

In the acid-decomposable resin, the compounds represented by the general formulas (pI) to (pV)
The content of the repeating structural unit containing an alkali-soluble group protected by the structure represented by I) is preferably from 30 to 70 mol%, more preferably 35 to 70 mol%, of all the repeating structural units.
６５65 mol%, more preferably 40-60 mol%. In the acid-decomposable resin, the content of the repeating structural units represented by the general formulas (III-a) to (III-d) is preferably 0 to 20 mol%, more preferably 0 to 18 mol% of all the repeating structural units.
Mol%, more preferably 0 to 16 mol%. In the acid-decomposable resin, the content of the acid-decomposable group-containing recurring structural unit other than the recurring structural unit containing an alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI) is the total content. 0-20 mol% is preferable in a repeating structural unit,
More preferably 0 to 18 mol%, further preferably 0 to 1 mol%.
6 mol%. In the acid-decomposable resin, the content of the repeating structural unit containing a lactone structure is 2% of the total repeating structural units.
The content is preferably 0 to 70 mol%, more preferably 25 to 65 mol%.
Mol%, more preferably 30 to 60 mol%.

The content of the repeating structural unit based on the monomer of the further copolymer component in the resin can be appropriately set according to the desired performance of the resist. It is preferably at most 99 mol%, more preferably at most 90 mol%, based on the total number of moles of the repeating structural units containing an alkali-soluble group protected by the structure represented by the formulas (pI) to (pVI), More preferably, it is at most 80 mol%.

The acid-decomposable resin used in the present invention has a monomer component content of 5% or less, preferably 0.01 to 4% of the total pattern area of gel permeation chromatography (GPC). Preferably 0.1 to
3%. Here, as GPC, for example, Showa Denko
Shodex system-11 manufactured by Co., Ltd. can be used. By setting the amount of the monomer contained in the acid-decomposable resin to the above-described content, high sensitivity, excellent edge roughness and pattern profile were obtained in the photoresist composition.

The acid-decomposable resin used in the present invention can be synthesized according to a conventional method (for example, radical polymerization).
The above-mentioned specific monomer amount can be preferably achieved by performing synthesis or recovery using at least one of the following means (i) to (iv). (I) A polymerization reaction is carried out by dropping a reaction solution containing each monomer and a radical initiator into a reaction solvent or a reaction solution containing a monomer. (Ii) The polymerization reaction is carried out by dividingly introducing the radical initiator into the reaction solution containing each monomer over 30 minutes to 8 hours. (Iii) After heating the reaction solution containing each monomer and the radical initiator to cause a polymerization reaction, the radical initiator is re-added thereto and heated again to cause a polymerization reaction. (Iv) After completion of the polymerization reaction, the reaction solution is treated with water, at least one of alcohols, water / alcohols, water / ethers, water / ketones, water / amides, water / esters or lactones, It is introduced into at least one liquid selected from the group of water / nitrile and recovered as a powder. In the present invention, among the above means, in particular, i) and ii
A combination of the means of i), a combination of ii) and iii), or a combination of these with the means of iv) is preferred.

A specific synthesis method is described below. The monomer to be reacted is added to the reaction solvent together with the initiator, and this is gradually dropped into a reaction solvent heated to a desired temperature or a solution in which a part of the monomer is added to the reaction solvent under a nitrogen atmosphere. Dropping method (method (i) above) After the monomer to be reacted is added to the reaction solvent to make it uniform, the mixture is heated and stirred under a nitrogen atmosphere to reach a desired temperature.
A method of conducting a polymerization reaction (method (ii) above) while dividingly adding a radical initiator in a predetermined time, and a method of adding a monomer to be reacted to a reaction solvent to be uniform, and then heating and stirring under a nitrogen atmosphere. After the desired temperature is reached, the radical initiator is added at once, the polymerization reaction is carried out, and then the initiator is added again (method (iii)) alone or in combination.

Preferably, the dropping method (i) is used. (I)
Although the details are not completely known, various resist properties such as resolution and edge roughness, which are the effects of the present invention, are further improved by selecting the dropping method. In the present invention, the reaction temperature in each of the above reactions can be appropriately set depending on the type of the initiator, but is generally from 30 ° C to 180 ° C. Preferably it is 40 to 160 degreeC, More preferably, it is 50 to 140 degreeC. The dropping time when the dropping method (i) is employed can be variously set depending on the reaction temperature, the type of the initiator, and the monomer to be reacted.
Time. It is preferably for 45 minutes to 6 hours, and more preferably for 1 hour to 5 hours. In the method (i), when the solution is dropped into the monomer-containing solution, the content of the monomer in the solution to be dropped is preferably 30 mol% or more based on the total amount of the monomers in (the solution to be dropped + the solution to be dropped). It is preferably at least 50 mol%, more preferably at least 70 mol%.

The time of introducing the initiator when the method (ii) is employed can be variously set depending on the reaction temperature, the type of the initiator and the monomer to be reacted, but is from 30 minutes to 8 hours. It is preferably for 45 minutes to 6 hours, and more preferably for 1 hour to 5 hours. In the method (ii), the injection interval of the initiator is preferably 10 minutes to 3 hours, more preferably 20 minutes to 2 hours 30 minutes, and further preferably 3 minutes to 3 hours.
0 minutes to 2 hours. The number of times of the injection is preferably 2 to 20 times, more preferably 3 to 15 times, and further preferably 4 to 10 times.

In the case of the method (ii) or (iii), after the addition of the initiator is completed, the mixture is heated and stirred at a desired temperature in a nitrogen atmosphere for a certain period of time. Also in the case of the dropping method (i), after completion of the dropping, the mixture is heated and stirred at a desired temperature for a certain period of time in a nitrogen atmosphere. The heating time varies depending on the reaction temperature and the type of the initiator, but is generally within 10 hours.
Preferably it is within 8 hours, more preferably within 6 hours. In any case, a method in which the heating and stirring are continued for a certain period of time and then the initiator is added again is preferable. By using the additional initiator, the sensitivity, the resolving power and the edge roughness are improved as a result although the details are unknown. After the addition of the initiator, the mixture is heated and stirred for a certain period of time. After the addition of the initiator, the reaction temperature may be increased.

As the solvent used in the reaction, any solvent can be used as long as it does not dissolve the monomer species used and inhibits polymerization (inhibition of polymerization, for example, nitrobenzenes, chain transfer, for example, mercapto compounds). Examples thereof include alcohols, ethers, ketones, amides, esters and lactones, nitriles and mixtures thereof. Methanol as alcohols,
Examples thereof include ethanol, propanol, isopropanol, butanol, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and 1-methoxy-2-propanol. As ethers, propyl ether, isopropyl ether, butyl methyl ether, tetrahydrofuran, 1,4-dioxane,
Examples thereof include 1,3-dioxolan and 1,3-dioxane. Ketones include acetone, methyl ethyl ketone, diethyl ketone, methyl isopropyl ketone,
Methyl isobutyl ketone can be mentioned. Examples of the amide include N, N-dimethylformamide and N, N-dimethylacetamide. Examples of the esters and lactones include ethyl acetate, methyl acetate, isobutyl acetate, and γ-butyrolactone. Nitriles include acetonitrile, propionitrile, and butyronitrile.

A preferred solvent is 1-methoxy-2-
Propanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, 1,4-dioxane, 1,3-dioxolan, 1,3-dioxane, methyl ethyl ketone, N, N
-Dimethylformamide, N, N-dimethylacetamide, γ-butyrolactone, acetonitrile. Mixed solvent systems include alcohols and ethers, alcohols and ketones, alcohols and amides, alcohols and esters and lactones, between ethers, ethers and ketones, ethers and amides, ethers and Esters and lactones, ethers and nitriles, ketones and amides, ketones and esters and lactones, ketones and nitriles, amides and esters and lactones, amides and nitriles, esters and lactones, Nitriles can be mentioned.

Preferred mixed solvent systems include 1-methoxy-2-propanol and tetrahydrofuran, 1-methoxy-2-propanol and 1,4-dioxane, 1-methoxy-2-propanol and 1,3-dioxolan,
Methoxy-2-propanol and 1,3-dioxane, 1
-Methoxy-2-propanol and methyl ethyl ketone,
1-methoxy-2-propanol and N, N-dimethylformamide, 1-methoxy-2-propanol and N, N
-Dimethylacetamide, 1-methoxy-2-propanol and γ-butyrolactone, ethylene glycol monomethyl ether and tetrahydrofuran, ethylene glycol monomethyl ether and 1,4-dioxane, ethylene glycol monomethyl ether and 1,3-dioxolan, ethylene glycol monomethyl ether 1,3-
Dioxane, ethylene glycol monomethyl ether and methyl ethyl ketone, ethylene glycol monomethyl ether and N, N-dimethylformamide, ethylene glycol monomethyl ether and N, N-dimethylacetamide, ethylene glycol monomethyl ether and γ-butyrolactone, ethylene glycol monoethyl ether and tetrahydrofuran, Ethylene glycol monoethyl ether and 1,4-dioxane, ethylene glycol monoethyl ether and 1,3-dioxolan, ethylene glycol monoethyl ether and 1,3-dioxane, ethylene glycol monoethyl ether and methyl ethyl ketone, ethylene glycol monoethyl ether and N, N
-Dimethylformamide, ethylene glycol monoethyl ether and N, N-dimethylacetamide, ethylene glycol monoethyl ether and γ-butylactone, tetrahydrofuran and 1,4-dioxane, tetrahydrofuran and 1,3-dioxolan, tetrahydrofuran and 1,3-dioxane , Detrahydrofuran and methyl ethyl ketone, tetrahydrofuran and N, N-dimethylformamide, tetrahydrofuran and N, N-dimethylacetamide, tetrahydrofuran and γ-butyrolactone,
Tetrahydrofuran and acetonitrile, methyl ethyl ketone and N, N-dimethylformamide, methyl ethyl ketone and N, N-dimethylacetamide, methyl ethyl ketone and γ-butyrolactone, methyl ethyl ketone and acetonitrile, N, N-dimethylformamide and γ-butyrolactone, N, N-dimethylacetamide γ-butyrolactone, N, N-dimethylformamide and acetonitrile, N, N-dimethylacetamide and acetonitrile, γ-butyrolactone and acetonitrile.

The amount of the reaction solvent used varies depending on the target molecular weight, the monomer used, the kind of the initiator used, and the like. When considering a solution of the monomer and the solvent, the monomer concentration is usually 12% by weight or less.
30% by weight. Preferably 14% to 28% by weight
And more preferably from 16% by weight to 26% by weight.

The following are examples of the radical initiator that can be used in the reaction of the present invention.
As the radical initiator, those generally used such as a peroxide and an azo initiator can be used. Preferred are azo-based initiators. Examples of the azo initiator include 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2-cyclopropylpropionitrile), and 2,2′-azobis (2 , 4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (2-methyl-N-
Phenylpropionamidine) dihydrochloride, 2,
2′-azobis (2-methyl-N-2-propenylpropionamidine) dihydrochloride, 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl)
Propane] dihydrochloride, 2,2'-azobis ｛2
-Methyl-N- [1,1-bis (hydroxymethyl) 2
-Hydroxyethyl] propionamide}, dimethyl-
2,2′-azobis (2-methylpropionate),
4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis (2- (hydroxymethyl)
Propionitrile).

As the radical initiator, preferably 2,2 '
Azobis (2,4-dimethylvaleronitrile), 2,
2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile), dimethyl-
2,2′-azobis (2-methylpropionate),
4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis (2- (hydroxymethyl)
Propionitrile).

In the present invention, after the polymerization reaction as described above, the obtained polymer (resin) is preferably recovered by a reprecipitation method. That is, after completion of the polymerization, the reaction solution is introduced into the reprecipitation solution, and the target resin is recovered as a powder. Examples of the reprecipitated solution include water, alcohols, ethers, ketones, amides, esters and lactones, nitriles alone and a mixture thereof. Alcohols include methanol, ethanol, propanol,
Isopropanol, butanol, ethylene glycol,
Propylene glycol and 1-methoxy-2-propanol can be mentioned. As ethers, propyl ether, isopropyl ether, butyl methyl ether, tetrahydrofuran, 1,4-dioxane, 1,3
-Dioxolane and 1,3-dioxane. Examples of ketones include acetone, methyl ethyl ketone, diethyl ketone, methyl isopropyl ketone, and methyl isobutyl ketone. Examples of the amide include N, N-dimethylformamide and N, N-dimethylacetamide. Examples of the esters and lactones include ethyl acetate, methyl acetate, isobutyl acetate, and γ-butyrolactone. Nitriles include acetonitrile, propionitrile,
Butyronitrile can be mentioned.

As the mixed liquid system, a mixed liquid system between alcohols, water / alcohols, water / ethers, water / ketones, water / amides, water / esters and lactones,
Water / nitrile systems can be mentioned. In particular,
Methanol and ethanol, methanol and propanol,
Methanol and isopropanol, methanol and butanol, ethylene glycol and ethanol, ethylene glycol and propanol, ethylene glycol and isopropanol, ethylene glycol and butanol, 1-methoxy-2-propanol and ethanol, 1-methoxy-2
-Propanol and propanol, 1-methoxy-2-propanol and isopropanol, 1-methoxy-2-propanol and butanol, water and methanol, water and ethanol, water and propanol, water and isopropanol, water and butanol, water and ethylene glycol, Water and propylene glycol, water and 1-methoxy-2-propanol, water and tetrahydrofuran, water and acetone, water and methyl ethyl ketone, water and N, N-dimethylformamide, water and N, N-dimethylacetamide, water and γ-butyrolactone , Water and acetonitrile. The mixing ratio of the mixed liquid system is from 20/1 to 1/20.

Preferred reprecipitates are water, at least one of alcohols, water / alcohols, water / ethers, water / ketones, water / amides, water / esters or lactones, water / nitrile. At least one liquid selected from the group of More preferred reprecipitates are water, methanol, isopropanol, water and methanol, water and ethanol, water and propanol, water and isopropanol, water and butanol, water and ethylene glycol, water and propylene glycol, water and 1-methoxy-2. -Propanol, water and tetrahydrofuran, water and acetone, water and methyl ethyl ketone, water and N, N-dimethylformamide, water and N, N-dimethylacetamide, water and γ-butyrolactone, water and acetonitrile. Particularly preferably, methanol and isopropanol, water and methanol, water and ethanol, water and propanol, water and isopropanol, water and ethylene glycol, water and 1-methoxy-2-propanol, water and tetrahydrofuran, water and acetone, water and methyl ethyl ketone , Water and acetonitrile.

JP-A-9-73173 and 10-2070
Reprecipitation liquid described in Nos. 69 and 10-274852 is extremely dangerous, such as extreme recharging in a hydrocarbon solvent typified by hexane and heptane, and is not preferable because of difficulty in workability. Further, for example, Japanese Patent Laid-Open No. 10-3012
It has been found that the operation of repeating re-precipitation as described in paragraph 85 merely increases the amount of waste liquid unnecessarily, resulting in inefficient operation and deterioration of edge roughness.
In the present invention, the number of times of reprecipitation may be one to three times, and is preferably one.

The amount of the reprecipitated solution is appropriately set depending on the amount and type of the solvent used during the polymerization and the type of the reprecipitated solution, but is 3 to 100 times the volume of the polymerization solution. Preferably it is 4 to 50 times, more preferably 5 to 30 times. If the amount is small, separation from the powder to be recovered becomes difficult, and the working efficiency is deteriorated. If the amount is large, the amount of waste liquid increases, which is not preferable in terms of cost.

The molecular weight of the acid-decomposable resin as described above is weight average (Mw: value in terms of polystyrene by GPC method).
And preferably 3,000 to 100,000, more preferably 4,000 to 70,000, and still more preferably 5,
It is in the range of 000 to 50,000. The larger the value, the better the heat resistance and the like, but the lower the developability and the like.

In the positive resist composition of the present invention,
The compounding amount of the acid-decomposable resin in the entire resist composition is preferably 40 to 99.99% by weight, more preferably 50 to 99.97% by weight, based on the total solid content.

Preferred specific examples of combinations of repeating structural units of the acid-decomposable resin (A) are shown below.

[0100]

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[0101]

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[0102]

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[0103]

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[2] (B) Compound that Generates Acid by Irradiation with Actinic Ray or Radiation (Photoacid Generator) The photoacid generator used in the present invention is a compound that generates an acid by irradiation with actinic ray or radiation. It is. As the photoacid generator used in the present invention, a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or a microresist is used. Publicly known light (ultraviolet light of 400 to 200 nm, far ultraviolet light, particularly preferably g-ray, h-ray, i-ray, KrF excimer laser light), ArF excimer laser light, electron beam, X-ray,
A compound that generates an acid by a molecular beam or an ion beam and a mixture thereof can be appropriately selected and used.

Other photoacid generators used in the present invention include, for example, onium salts such as diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts and arsonium salts;
Organic halogen compound, organic metal / organic halide, o
A photoacid generator having a nitrobenzyl-type protecting group; a compound represented by photolysis such as iminosulfonate that generates sulfonic acid; a disulfone compound; a diazoketosulfone; and a diazodisulfone compound.
Further, a group in which an acid is generated by such light or a compound in which a compound is introduced into a main chain or a side chain of a polymer can be used.

Further, VNRPillai, Synthesis, (1), 1 (198
0), A. Abad etal, Tetrahedron Lett., (47) 4555 (1971),
Compounds that generate an acid by light described in DHR Barton et al., J. Chem. Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, and EP 126,712 can also be used.

Among the compounds capable of decomposing upon irradiation with an electron beam to generate an acid, those particularly effectively used will be described below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PAG)
An S-triazine derivative represented by 2).

[0108]

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In the formula, R ²⁰¹ represents a substituted or unsubstituted aryl group or alkenyl group, and R ²⁰² represents a substituted or unsubstituted aryl group, alkenyl group, alkyl group, —C (Y) ₃
Show Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0110]

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(2) An iodonium salt represented by the following formula (PAG3) or a sulfonium salt represented by the following formula (PAG4).

[0112]

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Here, the formulas Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group. R ²⁰³ , R ²⁰⁴ ,
R ²⁰⁵ each independently represents a substituted or unsubstituted alkyl group or aryl group.

Z ^- represents a counter anion, for example, B
F ₄ ⁻ , AsF ₆ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , SiF ₆ ²⁻ , Cl
Condensed polynuclear aromatic sulfonic acid anions such as perfluoroalkanesulfonic acid anions such as O ₄ ⁻ and CF ₃ SO ₃ ⁻ , pentafluorobenzenesulfonic acid anion, naphthalene-1-sulfonic acid anion, anthraquinonesulfonic acid anion and sulfonic acid group Dyes and the like may be included, but are not limited thereto.

Further, two of R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ and Ar ¹ and Ar ² may be bonded through a single bond or a substituent.

Specific examples include the following compounds, but are not limited thereto.

[0117]

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[0118]

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[0119]

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[0120]

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[0121]

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[0122]

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[0123]

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The onium salts represented by the general formulas (PAG3) and (PAG4) are known and described, for example, in US Pat.
It can be synthesized by the methods described in 2,807,648 and 4,247,473, JP-A-53-101,331 and the like.

(3) Disulfone derivatives represented by the following formula (PAG5) or iminosulfonate derivatives represented by the following formula (PAG6).

[0126]

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In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group. R ²⁰⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, or arylene group. Specific examples include the following compounds, but are not limited thereto.

[0128]

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[0129]

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[0130]

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(4) A diazodisulfone derivative represented by the following general formula (PAG7).

[0132]

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Here, R represents a linear, branched or cyclic alkyl group or an optionally substituted aryl group. Specific examples include the following compounds, but are not limited thereto.

[0134]

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The amount of the photoacid generator to be added is usually in the range of 0.001 to 40% by weight, preferably 0.01 to 20% by weight, more preferably 0.01 to 20% by weight, based on the solid content in the composition. Is used in the range of 0.1 to 5% by weight. When the addition amount of the photoacid generator is less than 0.001% by weight, the sensitivity is lowered. When the addition amount is more than 40% by weight, the light absorption of the resist becomes too high, and the profile deteriorates,
The process (especially baking) margin is unfavorably reduced.

The positive resist composition of the present invention may further contain an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer,
A surfactant, a photosensitizer, an organic basic compound, and a compound that promotes solubility in a developer can be contained.

The positive resist composition of the present invention preferably contains a fluorine-based and / or silicon-based surfactant. In the positive resist composition of the present invention, any of a fluorine-containing surfactant, a silicon-containing surfactant and a surfactant containing both a fluorine atom and a silicon atom, or
It is preferable to contain two or more types. When the positive resist composition of the present invention contains the above-mentioned acid-decomposable resin and the above-mentioned surfactant, it is particularly effective when the line width of the pattern is thinner, the development defects are further improved, and the resolution of the contact hole is improved. The image quality becomes better. As these surfactants, for example, JP-A-62-36663, JP-A-61-22674
No. 6, JP-A-61-226745, JP-A-62-170950, JP-A-6
3-34540, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, and the surfactants described in JP-A-9-5988 can be mentioned, the following commercially available surfactants It can be used as it is. As commercially available surfactants that can be used, for example, F-top EF301, EF303, (manufactured by Shin-Akita Kasei Co., Ltd.), Florad FC430, 431 (manufactured by Sumitomo 3M Limited), Megafac F171, F173, F176, F189, R08 (Dai Nippon Ink Co., Ltd.), Surflon S-382, SC101, 102, 103, 10
4, 105, and 106 (manufactured by Asahi Glass Co., Ltd.) and the like. Also, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used as a silicon-based surfactant.

The amount of the surfactant is usually 0.001% by weight to 2% by weight, preferably 0.01% by weight to 1% by weight, based on the solid content in the composition of the present invention. These surfactants may be added alone or in some combination. Examples of the surfactant that can be used in addition to the above include, specifically, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether. , Polyoxyethylene alkyl allyl ethers such as polyoxyethylene octyl phenol ether, polyoxyethylene nonyl phenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan Sorbitan fatty acid esters such as monooleate, sorbitan trioleate, sorbitan tristearate, polyoxyethylene sorbitan Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as laurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate And the like. The amount of these other surfactants is usually 2 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the solids in the composition of the present invention.

Preferred organic basic compounds that can be used in the present invention are compounds that are more basic than phenol. Among them, a nitrogen-containing basic compound is preferable.

[0140]

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Here, R²⁵⁰, R²⁵¹And R²⁵²Are each
Independently, a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,
1-6 aminoalkyl groups, hydroxy having 1-6 carbon atoms
Alkyl group or substituted or unsubstituted 6 to 20 carbon atoms
An aryl group, where R ²⁵¹And R²⁵²Are connected to each other
To form a ring.

[0142]

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(Wherein R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R
²⁵⁶ independently represent an alkyl group having 1 to 6 carbon atoms.) Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms having different chemical environments in one molecule,
Particularly preferred are compounds containing both a substituted or unsubstituted amino group and a ring structure containing a nitrogen atom, or compounds having an alkylamino group. Preferred specific examples include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazol, substituted or unsubstituted Pyrazole, substituted or unsubstituted pyrazine,
Substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted aminomorpholine, substituted or unsubstituted amino And alkyl morpholine. Preferred substituents are an amino group, an aminoalkyl group, an alkylamino group, an aminoaryl group, an arylamino group, an alkyl group, an alkoxy group, an acyl group, an acyloxy group, an aryl group, an aryloxy group, a nitro group,
A hydroxyl group and a cyano group.

Preferred specific examples of the nitrogen-containing basic compound include guanidine, 1,1-dimethylguanidine,
1,3,3, -tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine,
-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-amino Ethyl) piperazine, N- (2-aminoethyl) piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) Pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-
3-methyl-1-p-tolylpyrazole, pyrazine, 2
-(Aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-
Aminomorpholine, N- (2-aminoethyl) morpholine, 1,5-diazabicyclo [4.3.0] nona-
5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,4-diazabicyclo [2.2.2]
Octane, 2,4,5-triphenylimidazole, N
-Methylmorpholine, N-ethylmorpholine, N-hydroxyethylmorpholine, N-benzylmorpholine, cyclohexylmorpholinoethylthiourea (CHMET
U) and other tertiary morpholine derivatives, JP-A-11-5257
No. 5 hindered amines (for example, those described in the gazette [0005]) and the like, but are not limited thereto.

Particularly preferred specific examples are 1,5-diazabicyclo [4.3.0] non-5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,4-diazabicyclo [2.2.2] Tertiary morpholines such as octane, 4-dimethylaminopyridine, hexamethylenetetramine, 4,4-dimethylimidazoline, pyrroles, pyrazoles, imidazoles, pyridazines, pyrimidines, CHMETU, etc., and bis Hindered amines such as (1,2,2,6,6-pentamethyl-4-piperidyl) sebagate and the like can be mentioned. Among them, 1,5-diazabicyclo [4.3.0] non-5-ene, 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) sebagate is preferred.

These nitrogen-containing basic compounds are used alone or in combination of two or more. The amount of the nitrogen-containing basic compound to be used is generally 0.001 to 10% by weight, preferably 0.01 to 5% by weight, based on the solid content of the entire photosensitive resin composition. If the amount is less than 0.001% by weight, the effect of the addition of the nitrogen-containing basic compound cannot be obtained. On the other hand, if it exceeds 10% by weight, the sensitivity tends to decrease and the developability of the unexposed portion tends to deteriorate.

The positive resist composition of the present invention is dissolved in a solvent capable of dissolving each of the above components and applied on a support. As the solvent used here, 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, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, lactic acid Ethyl, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-
Dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable, and these solvents are used alone or in combination.

Among the above, preferred solvents are 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, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate , N-methylpyrrolidone and tetrahydrofuran.

Such a positive resist composition of the present invention is applied on a substrate to form a thin film. The thickness of this coating film is preferably from 0.2 to 1.2 μm. In the present invention,
If necessary, a commercially available inorganic or organic antireflection film can be used.

As the anti-reflection film, an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, α-silicon, and an organic film type comprising a light absorbing agent and a polymer material can be used. The former requires equipment such as a vacuum deposition apparatus, a CVD apparatus, and a sputtering apparatus for film formation. As the organic antireflection film, for example, Japanese Patent Publication No. 7-69
No. 611, consisting of a condensate of a diphenylamine derivative and a formaldehyde-modified melamine resin, an alkali-soluble resin, and a light absorbing agent; a reaction product of a maleic anhydride copolymer and a diamine type light absorbing agent described in US Pat. No. 5,294,680; No. 6,118,631 containing a resin binder and a methylolmelamine-based thermal crosslinking agent; Japanese Patent Application Laid-Open No. 6-118656, an acrylic resin type antireflection film having a carboxylic acid group, an epoxy group and a light absorbing group in the same molecule; JP-A-8-87115, comprising a methylolmelamine and a benzophenone-based light-absorbing agent;
No. 79509 in which a low molecular weight light absorbing agent is added to a polyvinyl alcohol resin. As an organic anti-reflection film, DUV3 manufactured by Brewer Science Co., Ltd.
0 series, DUV-40 series, AC-2 and AC-3 manufactured by Shipley Co. can also be used.

The resist solution is applied onto a substrate (eg, a silicon / silicon dioxide coating) used for manufacturing precision integrated circuit devices (on a substrate provided with the antireflection film if necessary), a spinner, a coater, and the like. After coating by an appropriate coating method such as that described above, exposure through a predetermined mask, baking and development can provide a good resist pattern. Here, the exposure light is preferably 150
It is light having a wavelength of nm to 250 nm. Specifically, Kr
F excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157
nm), X-rays, electron beams and the like.

Examples of the developer include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia;
Primary amines such as ethylamine and n-propylamine;
Secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like An alkaline aqueous solution such as a quaternary ammonium salt, a cyclic amine such as pyrrole, or pyrhelidine can be used. Further, an appropriate amount of an alcohol or a surfactant may be added to the above alkaline aqueous solution.

[0153]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples.

(1) Synthesis of Resin (1) -1 (Drip Method A) 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 100 mL of a solution having a solid content of 20%. To this solution was added Wako Pure Chemical V-65 (2,2'-
Azobis (2,4-dimethylvaleronitrile) 1mol
% And 1 mol% of mercaptoethanol were added dropwise to 10 mL of N, N-dimethylacetamide heated to 60 ° C. over 2 hours under a nitrogen atmosphere. After the addition was completed, the reaction solution was heated and stirred for 3 hours. Here, V-65 is again set to 1
mol% was added, and the reaction solution was heated and stirred for 3 hours. After the completion of the reaction, the reaction solution was cooled to room temperature, and crystallized and precipitated in 1.5 L of a mixed solvent of methanol / distilled water = 3/1 to collect white powder. The polymer composition ratio determined from C ¹³ NMR was 44/56. GPC (Showa Denko KK)
Shodex system-11) The weight average molecular weight in terms of standard polystyrene determined by measurement was 11,900, and the area ratio of the monomer was 1.1%. The area ratio of the monomer was measured using an RI detector (the same applies hereinafter).

(2) Synthesis of resin (1) -2 (dropping method B) 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 100 mL of a solution having a solid content of 20%. To this solution was added Wako Pure Chemical V-65 (2,2'-
Azobis (2,4-dimethylvaleronitrile) 2mol
% Was added dropwise to 10 mL of N, N-dimethylacetamide heated to 60 ° C. over 2 hours under a nitrogen atmosphere. After the addition was completed, the reaction solution was heated and stirred for 3 hours. Here, 1 mol% of V-65 was added again, and the reaction solution was heated and stirred for 3 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and 1.5 L of a mixed solvent of methanol / distilled water = 3/1.
The white powder crystallized and precipitated was recovered. The polymer composition ratio determined from C ¹³ NMR was 44/56. G
The weight average molecular weight in terms of standard polystyrene determined by PC measurement was 10,200, and the area ratio of monomer was 1.0%.

(3) Synthesis of Resin (1) -3 (Drip Method C) 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran =
The solution was dissolved in 3/7 to prepare 100 mL of a solution having a solid content of 20%. To this solution was added Wako Pure Chemical V-65 (2,2'-
1 mol of azobis (2,4-dimethylvaleronitrile)
1% of mercaptoethanol and 1 mol% of mercaptoethanol were added dropwise to 10 mL of N, N-dimethylacetamide heated to 60 ° C. over 2 hours under a nitrogen atmosphere. After the addition was completed, the reaction solution was heated and stirred for 3 hours. After the completion of the reaction, the reaction solution was cooled to room temperature, and crystallized and precipitated in 1.5 L of a mixed solvent of methanol / distilled water = 3/1 to collect white powder. C ¹³ N
The polymer composition ratio determined from MR was 44/56.
The weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 12,500, and the area ratio of the monomer was 2.
4%.

(4) Synthesis of Resin (1) -4 (Drip Method D) 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 120 mL of a solution having a solid content of 18%. 20% of this solution was taken out and charged into a reaction vessel. Next, Wako Pure Chemical V-65 was added to the remaining solution 80%.
2 mol% of (2,2′-azobis (2,4-dimethylvaleronitrile)) was added, and this was added dropwise to the previous solution (“20% solution”) heated to 60 ° C. over 2 hours in a nitrogen atmosphere. did. After the addition was completed, the reaction solution was heated and stirred for 3 hours. Here, 1 mol% of V-65 was added again, and the reaction solution was heated and stirred for 3 hours. After the reaction was completed, the reaction solution was cooled to room temperature, and white powder precipitated and crystallized in 1.5 L of a mixed solvent of isopropanol / distilled water = 3/1 was recovered.
The polymer composition ratio determined from C ¹³ NMR was 44/56. The weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 11100, and the area ratio of the monomer was 0.8%.

(5) Synthesis of Resin (1) -5 (Batch Method A) 2-ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 120 mL of a solution having a solid content of 18%. This solution was heated and stirred at 60 ° C. under a nitrogen atmosphere. When the temperature became constant, V-65 manufactured by Wako Pure Chemical Industries, Ltd. was used.
2 mol% of (2,2′-azobis (2,4-dimethylvaleronitrile)) was added. After the addition, the reaction solution was heated and stirred for 3 hours. Here, 1 mol% of V-65 is added again,
The reaction was heated and stirred for 3 hours. After the completion of the reaction, the reaction solution was cooled to room temperature, and 1.5 L of a mixed solvent of methanol / distilled water = 3/1 was crystallized, and a white powder precipitated was recovered.
The polymer composition determined from C ¹³ NMR was 44/56. The weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 12,400, and the area ratio of the monomer was 4.5%.

(6) Synthesis of Resin (1) -R (Batch Method B): Comparative Example 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 120 mL of a solution having a solid content of 18%. This solution was heated and stirred at 60 ° C. under a nitrogen atmosphere. When the temperature became constant, V-65 manufactured by Wako Pure Chemical Industries, Ltd. was used.
2 mol% of (2,2′-azobis (2,4-dimethylvaleronitrile)) was added. After the addition, the reaction solution was heated and stirred for 3 hours. After the reaction was completed, the reaction solution was cooled to room temperature, and crystallized and precipitated in 1.5 L of a mixed solvent of methanol / distilled water = 3/1 to collect white powder. The polymer composition ratio determined from C ¹³ NMR was 44/56. Also, GPC
The weight average molecular weight in terms of standard polystyrene determined by measurement was 13,100, and the area ratio of the monomer was 5.8%.

(7) Synthesis of resin (1) -6 (divisional addition method A) 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 120 mL of a solution having a solid content of 18%. This solution was heated and stirred at 60 ° C. under a nitrogen atmosphere. When the temperature became constant, V-65 manufactured by Wako Pure Chemical Industries, Ltd. was used.
2 mol% of (2,2′-azobis (2,4-dimethylvaleronitrile)) was added in four portions every 30 minutes.
After the addition, the reaction solution was heated and stirred for 3 hours. Here, 1 mol% of V-65 was added again, and the reaction solution was heated and stirred for 3 hours. After the completion of the reaction, the reaction solution was cooled to room temperature and crystallized in 1.5 L of a mixed solvent of methanol / distilled water = 3/1.
The precipitated white powder was recovered. The polymer composition ratio determined from C ¹³ NMR was 44/56. Further, the weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 12,100, and the area ratio of the monomer was 3.1%.

(8) Synthesis of Resin (1) -7 (Division Addition Method B) 2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 40/60, and N, N-dimethylacetamide / tetrahydrofuran was used.
The solution was dissolved in 3/7 to prepare 120 mL of a solution having a solid content of 18%. This solution was heated and stirred at 60 ° C. under a nitrogen atmosphere. When the temperature became constant, V-65 manufactured by Wako Pure Chemical Industries, Ltd. was used.
2 mol% of (2,2′-azobis (2,4-dimethylvaleronitrile)) was added in four portions every 30 minutes.
After the addition, the reaction solution was heated and stirred for 4 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and methanol / distilled water = 3.
A white powder crystallized and precipitated in 1.5 L of a mixed solvent of / 1 was recovered. The polymer composition ratio determined from C ¹³ NMR was 44 /
56. The weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 12,700, and the area ratio of the monomer was 4.3%. Resin (2) -1 to (15) of the composition ratio, molecular weight, and residual monomer shown in the following table were synthesized by the same operation as in the above synthesis example (the number of the repeating unit was as described in (2) to (15) above). The repeating units 1 and 2 in the structure of the resin represent the order from the left of the structural formula).

[0162]

[Table 1]

Solvent a; distilled water solvent b; methanol solvent c; isopropyl alcohol solvent d; 1-methoxy-2-propanol solvent e; tetrahydrofuran solvent f; methyl ethyl ketone solvent g; N, N-dimethylacetamide solvent h; γ-butyrolactone Solvent i; acetonitrile In addition, regarding the used initiator, as follows, 2,2'-azobisisobutyronitrile; resins 2, 6,
7 Dimethyl 2,2'-azobis (2-methylpropionate); Resins 4, 14 Others are 2,2'-azobis (2,4-dimethylvaleronitrile)

Examples 1 to 31 and Comparative Example 1 (Preparation and Evaluation of Positive Resist Composition) 1.4 g of each of the resins shown in Tables 2 and 3 synthesized in the above Synthesis Examples was prepared.
0.2 g of the photoacid generator shown in Tables 2 and 3, 10 mg of the organic basic compound (amine), and if necessary, a surfactant (0.15
g), and dissolved in propylene glycol monoethyl ether acetate at a solid content of 14% by weight, respectively, and then filtered through a 0.1 μm microfilter to obtain positive resist compositions of Examples 1 to 31 and Comparative Examples. Was prepared.

[0165]

[Table 2]

[0166]

[Table 3]

In Tables 2 and 3 below, 1 represents triphenylsulfonium triflate and 2 represents the above (PAG4-36) as a photoacid generator. As the amine, 1 is 1,5-diazabicyclo [4.3.0] -5-
Represents nonene (DBN) and 2 is bis (1,2,2,6)
6-pentamethyl-4-piperidyl) sebagate. As the surfactant, W1: Megafac F176 (manufactured by Dainippon Ink and Chemicals, Inc.)
(Fluorine) W2: Megafac R08 (Dai Nippon Ink Co., Ltd.)
(Fluorine and silicone type) W3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) W4: represents polyoxyethylene nonylphenyl ether.

(Evaluation Test) The obtained positive resist solution was applied on a silicon wafer using a spin coater.
After drying at 135 ° C. for 90 seconds, a positive photoresist film having a thickness of about 0.4 μm was formed and exposed to an ArF excimer laser (exposed by an ISI ArF stepper having a wavelength of 193 nm and NA = 0.6). A heat treatment after the exposure was performed at 120 ° C. for 90 seconds, developed with a 2.38% aqueous solution of tetramethylammonium hydroxide, and rinsed with distilled water to obtain a resist pattern profile. For these, sensitivity, profile, and edge roughness were evaluated as follows. Tables 2 and 3 show the evaluation results.

[Sensitivity]: The relative light exposure was defined assuming that the light exposure for reproducing a line width of 0.18 μm was 1 in Example 1. [Profile]: Observe the profile of a 0.18 μm 1/1 line and space line with a scanning electron microscope. The rectangular profile is ○, the slightly tapered or slightly skirted profile is △, the complete taper The shape and the profile of the slightly hemmed shape were evaluated as x. [Edge Roughness]: The edge roughness is measured using a length-measuring scanning electron microscope (SEM) with the edge roughness of an isolated pattern, and a line pattern edge is detected at a plurality of positions in a measurement monitor, and the detection is performed. The variance (3σ) of the variation in position is used as an index of the edge roughness, and the smaller the value, the better.

As is clear from the results shown in Tables 2 and 3, the positive resist composition of the present invention has a sufficient sensitivity, a good profile, and an excellent edge roughness.

[0171]

The positive resist composition of the present invention is suitable for far ultraviolet light, particularly ArF excimer laser light having a wavelength of 193 nm, has high sensitivity, and has excellent performance in edge roughness. The profile is excellent. Therefore, it is suitably used for lithography using far ultraviolet rays such as ArF excimer laser exposure.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/36 C08K 5/36 C08L 33/04 C08L 33/04 H01L 21/027 H01L 21/30 502R (72 ) Inventor Toshiaki Ao 4,000 Kawajiri, Yoshida-cho, Haibara-gun, Shizuoka Pref.F-term in Fujisha Shin Film Co., Ltd. FD206 GP03 4J011 AA05 HA03 HB05 HB06 HB13 HB22 4J100 AJ02R AL08P AL08Q AL08R AM21R BA02R BA03R BA11R BA15Q BA55R BA58R BC23R BC26P BC52Q CA04 CA05 DA28 FA03 GC07

Claims (5)

[Claims] (A) The following general formula (pI) to general formula (p
VI) The alkali-soluble group protected by at least one of the alicyclic hydrocarbon-containing partial structures represented by the formula (VI), and the content of the monomer component is 5% of the total pattern area of gel permeation chromatography (GPC). % Or less, a resin whose dissolution rate in an alkali developing solution is increased by the action of an acid, (Wherein, R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z represents an alicyclic hydrocarbon group together with a carbon atom. Represents an atomic group necessary for forming R ₁₂
To R ₁₆ each independently represent a linear or branched alkyl group or an alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ or R ₁₅ ,
Any of R ₁₆ represents an alicyclic hydrocarbon group. R _{17 to} R ₂₁
Each independently represents a hydrogen atom, a C1 to C4 linear or branched alkyl group or an alicyclic hydrocarbon group,
However, at least one of R _{17 to} R ₂₁ represents an alicyclic hydrocarbon group. Further, any of R ₁₉ and R ₂₁ has 1 to 1 carbon atoms.
Represents four linear or branched alkyl groups or alicyclic hydrocarbon groups. R _{22 to} R ₂₅ each independently have 1 to 1 carbon atoms.
It represents four linear or branched alkyl groups or alicyclic hydrocarbon groups, provided that at least one of R _{22 to} R ₂₅ represents an alicyclic hydrocarbon group. (B) A positive resist composition comprising a compound that generates an acid upon irradiation with actinic rays or radiation. 2. The resin of (A), which is a resin obtained by dropping a reaction solution containing a monomer and a radical initiator into a reaction solvent or a reaction solution containing a monomer and causing a polymerization reaction. The positive resist composition according to claim 1, wherein: 3. The resin according to claim 1, wherein the resin (A) is a resin obtained by dividing and injecting a radical initiator into a reaction solution containing a monomer over 30 minutes to 8 hours to carry out a polymerization reaction. The positive resist composition according to claim 1, wherein: 4. The resin of (A) undergoes a polymerization reaction by heating a reaction solution containing a monomer and a radical initiator, and then re-adds the radical initiator thereto and heats again to cause a polymerization reaction. The positive resist composition according to any one of claims 1 to 3, which is a resin obtained by the above method. 5. After the polymerization reaction of the resin (A) is completed, the reaction solution is mixed with at least one of water and alcohols.
Water / alcohols, water / ethers, water / ketones, water / amides, water / esters or lactones, water /
The positive resist composition according to any one of claims 1 to 4, wherein the resin is a resin which is charged into at least one liquid selected from the group of nitriles and recovered as a powder.