JP2003122012A - Positive resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive resist composition excellent in various characteristics such as resolution and dependence on the pattern density. SOLUTION: The positive resist composition is characterized in containing (A) a compound which generates a fluorine-substituted sulfonic acid having 2 or more carbon atoms by irradiation of active rays or radiation and (B) a resin which contains a specified repeating unit and which decomposes by the effect of an acid to increase the solubility with an alkali developer liquid.

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 production of an ultra-LSI or a high-capacity microchip and other photofabrication processes. More specifically, it relates to a positive resist composition capable of forming a highly fine pattern by using light having a deep ultraviolet region including excimer laser light, particularly light having a wavelength of 250 nm or less.

[0002]

2. Description of the Related Art In recent years, the degree of integration of integrated circuits has been increasing, and in the manufacture of semiconductor substrates such as VLSI, it has become necessary to process ultrafine patterns having line widths of half micron or less. Has become. In order to meet the need, the wavelength of the exposure apparatus used for photolithography has become shorter and shorter, and now, excimer laser light (XeCl, KrF, ArF, etc.) with a short wavelength in far ultraviolet rays is being used.
Is being considered. A chemically amplified resist is used as a pattern for lithography in this wavelength region.

As a resist composition for an ArF light source, a resin having an alicyclic hydrocarbon moiety introduced for the purpose of imparting dry etching resistance has been proposed. As such a resin, a monomer having a carboxylic acid moiety such as acrylic acid or methacrylic acid or a monomer having a hydroxyl group or a cyano group in the molecule is copolymerized with a monomer having an alicyclic hydrocarbon group. Resin.

On the other hand, in addition to the method of introducing an alicyclic hydrocarbon moiety into the side chain of the acrylate-based monomer, a method of imparting dry etching resistance utilizing an alicyclic hydrocarbon moiety as a polymer main chain has also been studied. ing. In addition, JP-A-9
-73173, JP-A-9-90637, JP-A-10
JP-A-161313 discloses an acid-sensitive compound containing an alkali-soluble group protected by a structure containing an alicyclic group and a structural unit capable of eliminating the alkali-soluble group with an acid to make it alkali-soluble. The resist material that was used is described. Further, a resin in which a hydrophilic 5-membered or 6-membered lactone group is introduced into a resin having these alicyclic groups for the purpose of improving affinity to an alkali developing solution and adhesion to a substrate is disclosed in JP-A 9-90637, JP-A-10-207069, and JP-A-10-274852.
And JP-A-10-239846. Further, JP 2001-81139 A describes a resist composition containing a resin having a specific cyclic alicyclic skeleton introduced therein. The acid generator used in Japanese Unexamined Patent Publication No. 2001-81139 is a compound that generates trifluoromethanesulfonic acid, and trifluoromethanesulfonic acid has a high diffusibility and thus has a problem of dense / dense dependence. Further, since trifluoromethanesulfonic acid has high volatility, there is a problem that the volatilized trifluoromethanesulfonic acid pollutes the device.

Even with the techniques described above, in the resist composition (particularly, the resist for exposure to deep ultraviolet rays), there still exist improvements due to the resin containing an acid-decomposable group.
For example, in these compositions, further improvement in resolution has been desired.

Furthermore, there is room for improvement in the problem of sparse / dense dependence. Since various patterns are included in the trend of recent devices, various performances are required for resists, and one of them is sparse / dense dependence. That is, the device has a portion where lines are densely arranged, a pattern having a wider space as compared with a line, and an isolated line. Therefore, it is important to resolve various lines with high reproducibility. However, it is not always easy to reproduce various lines due to optical factors, and it is the current situation that the solution method using resist is not clear. Particularly, in the above-mentioned resist system containing an alicyclic group, the performance difference between the isolated pattern and the dense pattern is remarkable, and improvement is desired.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a chemically amplified positive resist composition which is excellent in resolution and various characteristics of density dependence.

[0008]

Means for Solving the Problems As a result of diligent studies on the constituent materials of a positive type chemically amplified resist composition, the present inventors have found that by using a specific photo-acid generator and a specific acid-decomposable resin, The inventors have found that the object of the present invention is achieved, and have reached the present invention. That is, the above object is achieved by the following configurations.

(1) (A) a compound capable of generating a fluorine-substituted sulfonic acid having 2 or more carbon atoms upon irradiation with actinic rays or radiation; and (B) at least one selected from the following general formulas (1) and (2) A positive resist composition containing a repeating unit of, which is decomposed by the action of an acid to increase its solubility in an alkali developing solution.

[0010]

[Chemical 2]

In the general formula (1), R₁Is an alkyl group or
Represents an acid-decomposable group. m represents an integer of 0-4. n is
Represents an integer of 0-10. multiple when n is an integer of 2 or more
R ₁May be the same or different. General formula (2)
Medium, R₂And R₃Are the same or different, hydrogen
Atom, alkyl group, cycloalkyl group or acid-eliminating property
Represents a guardian.

(2) The positive resist composition as described in (1), wherein the compound of the component (A) is a sulfonium salt.

(3) The positive resist composition as described in (1) or (2), which further comprises a basic compound and a fluorine-based surfactant or a silicon-based surfactant.

(4) The basic compound is an alkylamine structure, an alkylamine structure having an ether bond, an alkylamine structure having a hydroxyl group, an aniline structure, a pyridine structure, a diazabicyclo structure, an ammonium hydroxide structure, an ammonium carboxylate structure and imidazole. The positive resist composition as described in (3), which is a compound having at least one structure selected from structures.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Each component used in the present invention will be described in detail below. <(A) Compound that generates a fluorine-substituted sulfonic acid having 2 or more carbon atoms upon irradiation with actinic rays or radiation (also referred to as photoacid generator or component (A))> In the present invention, a preferable photoacid generator is: cation portion is composed of iodonium or sulfonium, anionic part R ^F SO ₃ ^- (wherein, R ^F
Is a fluorine-substituted alkyl group having 2 or more carbon atoms) can be used.

The cation moiety has the following general formulas (IA) and (II
The photoacid generator represented by A) or (IIIA) is preferable.

[0017]

[Chemical 3]

In the above general formulas (IA) to (IIIA): R ₁ to
R ₃₇ is the same or different and is a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group, a halogen atom, or
It represents an S-R ₃₈ group. R ₃₈ represents a linear, branched or cyclic alkyl group or aryl group. In addition, R ₁ ~
Two or more of R ₁₅ , R _{16 to} R ₂₇ , and R _{28 to} R ₃₇ are bonded to form a ring containing one or more selected from a single bond, carbon, oxygen, sulfur, and nitrogen. It may be formed.

[0019] In the present invention, the anion part R ^F SO ₃ ^- (wherein, R ^F is 2 or more carbon atoms, preferably carbon atoms 2-2
0, and more preferably a C 4-8 fluorine-substituted alkyl group) is used. The fluorine-substituted alkyl group represented by R ^F may be linear, branched or cyclic. Preferred R ^F is represented by CF ₃ (CF ₂ ) y, where y is 1 to
It is a fluorine-substituted linear alkyl group that is an integer of 19.
The alkyl group as R ^F may have a substituent such as a hydroxyl group and a cyano group, and is —O—, —S—, or —C.
O -, - COO -, - NHCO -, - CONHSO 2 -
It may contain a divalent linking group such as. In this case, the carbon number of R ^F includes the carbon number of the linking group. Further, the alkyl group represented by R ^F may be substituted with one or more fluorine atoms, and preferably the hydrogen atom of the carbon atom at the α-position of sulfonic acid is substituted with a fluorine atom. The most preferable anion moiety in the present invention is perfluorobutane sulfonate, perfluorooctane sulfonate and the like.

The cation portion of the photoacid generator is preferably represented by the above general formulas (IA) to (IIIA). General formula (I
In A) to (IIIA), the linear or branched alkyl group for R _{1 to} R ₃₈ may have a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include those having 1 to 4 carbon atoms such as butyl group and t-butyl group. Examples of the cyclic alkyl group include those having a carbon number of 3 to 8, such as cyclopropyl group, cyclopentyl group and cyclohexyl group, which may have a substituent. Examples of the linear or branched alkoxy group for R _{1 to} R ₃₇ include, for example, methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, t-butoxy group. Those having 1 to 4 carbon atoms can be mentioned. Examples of the cyclic alkoxy group include a cyclopentyloxy group, for example, a cyclopentyloxy group and a cyclohexyloxy group. R
Examples of the halogen atom of _{1 to} R ₃₇ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the aryl group of R ₃₈ include a phenyl group, a tolyl group,
Examples thereof include those having 6 to 14 carbon atoms which may have a substituent such as a methoxyphenyl group and a naphthyl group. As these substituents, an alkoxy group having 1 to 4 carbon atoms, a halogen atom (fluorine atom, chlorine atom, iodine atom), an aryl group having 6 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms are preferable. , Cyano group, hydroxy group, carboxy group, alkoxycarbonyl group, nitro group and the like.

Further, R _{1 to} R ₁₅ , R _{16 to} R ₂₇ , R _{28 to} R
Carbon, oxygen, which is formed by combining two or more of ₃₇
Examples of the ring containing one or more selected from sulfur and nitrogen include a furan ring, a dihydrofuran ring,
Examples thereof include a pyran ring, a trihydropyran ring, a thiophene ring and a pyrrole ring.

Further, the following general formula (IVA) or (VA)
The photoacid generator represented by is also preferable.

Examples of the compound having a phenacylsulfonium salt structure which generates an acid upon irradiation with actinic rays or radiation include compounds represented by the following general formula (IVA).

[0024]

[Chemical 4]

R _{1c to} R _5c each independently represents 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. Rx and Ry each independently represent an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, or a vinyl group. R _{1c to} R _7c
Any two or more of them, and Rx and Ry may be bonded to each other to form a ring structure, and this ring structure may contain an oxygen atom, a sulfur atom, an ester bond or an amide bond. X ⁻ represents R ^F SO ₃ ⁻ . R ^F is the same as that described above.

The alkyl group as R _{1c to} R _5c is a straight chain,
It may be branched or cyclic, and has, for example, 1 to 1 carbon atoms.
10 alkyl groups, preferably linear and branched alkyl groups having 1 to 5 carbon atoms (for example, methyl group, ethyl group, linear or branched propyl group, linear or branched butyl group, linear or branched pentyl group). And a cyclic alkyl group having 3 to 8 carbon atoms (eg, cyclopentyl group, cyclohexyl group). The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic. For example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, a methoxy group, an ethoxy group, a linear or branched propoxy group, a linear or branched butoxy group, a linear or branched pentoxy group), a cyclic alkoxy group having 3 to 8 carbon atoms (for example, a cyclopentyloxy group,
And a cyclohexyloxy group). Preferably, any of R _{1c to} R _{5c is} a linear, branched or cyclic alkyl group, or a linear, branched or cyclic alkoxy group,
More preferably, the sum of carbon numbers of R _1c to R _5c is 2 to 15. Thereby, the solvent solubility is further improved, and the generation of particles during storage is suppressed.

_Examples of the alkyl group as R _6c and R _7c include the same as the alkyl group as R _{1c to} R _5c . Examples of the aryl group may include an aryl group having 6 to 14 carbon atoms (for example, a phenyl group). Alkyl groups as Rx and Ry are R _1c
The same examples of the alkyl group as R 5 to R _5c can be mentioned. 2-oxoalkyl group include a group having> C = O at the 2-position of the alkyl group as R _1c to R _5c. As the alkoxy group in the alkoxycarbonylmethyl group, the same alkoxy groups as R _{1c to} R _5c can be mentioned. Examples of the group formed by combining Rx and Ry include a butylene group and a pentylene group.

The compound of formula (IVA) forms a ring
As a result, the three-dimensional structure is fixed and the optical resolution is improved. R_1c
~ R_7cWhen any two of them combine to form a ring structure
For the case, R_1c~ R_5cAny one of and R_6cAnd R
_7cAny one of the above forms a single bond or a linking group.
It is preferred that a ring is formed, especially R_5cAnd R_6cOr
R _7cCombine to form a single bond or linking group to form a ring
The case is preferred. The linking group has a substituent
Good alkylene group, optionally substituted alkyl group
Nylene group, -O-, -S-, -CO-, -CONR-
(R is a hydrogen atom, an alkyl group or an acyl group), and
A group formed by combining two or more of these can be mentioned.
In addition, an alkylene group which may have a substituent,
Alkylene containing oxygen atom, alkyle containing sulfur atom
Group is preferred. As the substituent, an alkyl group (preferably
Or C1-5), an aryl group (preferably C6)
-10, eg phenyl group, acyl group (eg carbon)
Examples 2 to 11) can be cited. In addition,
Group, ethylene group, propylene group, -CH₂-O-,-
CH₂A linking group that forms a 5- to 7-membered ring such as -S- is preferred.
Much better, ethylene group, -CH₂-O-, -CH₂-S-
Particularly preferred are linking groups which form a 6-membered ring. 6
By forming a member ring with the carbonyl plane and C-S + Si
The bear bond becomes more vertical and the orbital interaction causes light
The resolution is improved. Also, R_1c~ R_7cAnd Rx and Ry
Bonded at a single position via a single bond or a linking group,
Even a compound having two or more structures of formula (IVA)
Good.

The sulfonium salt having no aromatic ring is a salt having sulfonium represented by the following formula (VA) as a cation.

[0030]

[Chemical 5]

In the formula, R ^{1b to} R ^3b each independently represents an aromatic ring-free organic group. Here, the aromatic ring also includes an aromatic ring containing a hetero atom. R ^1b ~
Two of R ^3b may combine with each other to form a ring structure. X ⁻ represents R ^F SO ₃ ⁻ . R ^F is the same as that described above.

The organic group containing no aromatic ring as R ^{1b to} R ^3b generally has 1 to 30 carbon atoms, preferably 1 carbon atom.
~ 20. R ^{1b to} R ^3b are each independently preferably an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group or a vinyl group, more preferably a linear, branched or cyclic 2-oxoalkyl group, Alkoxycarbonylmethyl group, most preferably linear, branched 2-
It is an oxoalkyl group. The alkyl group as R ^{1b to} R ^3b may be linear, branched, or cyclic, and is preferably a linear or branched alkyl group having 1 to 10 carbon atoms (eg, methyl group, ethyl group, propyl group). Group, butyl group, pentyl group) and cyclic alkyl groups having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group). The 2-oxoalkyl group as R ^{1b to} R ^3b may be linear, branched or cyclic,
Preferred is a group having> C = O at the 2-position of the above alkyl group. The alkoxy group in the alkoxycarbonylmethyl group as R ^{1b to} R ^3b is preferably an alkyl group having 1 to 5 carbon atoms (methyl group,
And ethyl group, propyl group, butyl group, pentyl group). R ^{1b to} R ^3b may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group or a nitro group. R ^{1b to} R ^3b
Two of them may combine to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond or a carbonyl group. The group formed by combining two members out of R ^{1b to} R ^3b is an alkylene group (for example,
Butylene group and pentylene group). From the viewpoint of photoreactivity, a group in which any one of R ^{1b to} R ^3b has a carbon-carbon double bond or a carbon-oxygen double bond is preferable. R ^{1b of the} compound represented by the general formula (VA)
At least one to R ^3b is, may take at least one coupling to the structure of R ^1b to R ^3b of the general formula (VA) Other compounds of the general.

In the present invention, a photoacid generator having a sulfonium salt as a cation moiety is preferable, and as the sulfonium salt, a triarylsulfonium salt, a phenacylsulfonium salt, or an alkylsulfonium salt having a 2-oxoalkyl group is used. Is particularly preferable.

Preferred specific examples (A1-1) to (A1-91) of the photoacid generator (A) that can be used in the present invention.
Is shown below.

[0035]

[Chemical 6]

[0036]

[Chemical 7]

[0037]

[Chemical 8]

[0038]

[Chemical 9]

[0039]

[Chemical 10]

[0040]

[Chemical 11]

[0041]

[Chemical 12]

[0042]

[Chemical 13]

[0043]

[Chemical 14]

[0044]

[Chemical 15]

[0045]

[Chemical 16]

In the present invention, the addition amount of the photoacid generator as the component (A) is usually 0.001 to 40% by weight, preferably 0.01% by weight, based on the solid content in the composition. It is used in an amount of -20% by weight, more preferably 0.1-5% by weight. Addition amount of photo-acid generator is 0.0
If it is less than 01% by weight, the sensitivity is low, and if it is more than 40% by weight, the light absorption of the resist becomes too high, the profile is deteriorated and the process (particularly baking) margin is narrowed, which is not preferable.

The sulfonium salt of the photoacid generator (A) is obtained by reacting an aryl Grignard reagent such as arylmagnesium bromide with a substituted or unsubstituted phenyl sulfoxide, and the obtained triarylsulfonium halide is salted with a corresponding sulfonic acid. Exchange method, or substituted or unsubstituted phenyl sulfoxide and the corresponding aromatic compound are condensed using methanesulfonic acid / diphosphorus pentoxide or an acid catalyst such as aluminum chloride and subjected to salt exchange, diaryl iodonium salt and diaryl sulfide. Can be synthesized by a method such as condensation and salt exchange using a catalyst such as copper acetate. The iodonium salt of the photoacid generator (A) can be synthesized by reacting an aromatic compound with a periodate and subjecting the obtained iodonium salt to salt exchange with a corresponding sulfonic acid. As the sulfonic acid or sulfonate used for salt exchange, a commercially available sulfonic acid can be used as it is, or can be obtained by hydrolysis of a sulfonic acid halide.

In the positive resist composition of the present invention, a photo-acid generator other than the compounds specified above can be used in combination. As the photoacid generator that can be used in combination, a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization,
Known light used for photo-decoloring agents of dyes, photo-discoloring agents, micro resists, etc. (ultraviolet rays of 400 to 200 nm, deep ultraviolet rays, particularly preferably g-line, h-line, i-line)
Ray, KrF excimer laser light), ArF excimer laser light, an electron beam, an X-ray, a molecular beam or an ion beam to generate an acid, and a mixture thereof can be appropriately selected and used.

Other photoacid generators that can be used in combination include, for example, diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, arsonium salts, and other onium salts, organic halogen compounds, and organic metal / Examples include organic halides, photoacid generators having an o-nitrobenzyl-type protecting group, compounds that generate sulfonic acid by photolysis represented by iminosulfonates, disulfone compounds, diazoketosulfones, diazodisulfone compounds, and the like. be able to. Further, a group in which an acid is generated by such light or a compound in which a compound is introduced into the main chain or side chain of a polymer can be used together.

Further, VNR Villai, Synthesis, (1), 1 (198
0), A. Abad et al, Tetrahedron Lett., (47) 4555 (1971),
DHR Barton et al., J. Chem. Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, and European Patent 126,712 can be used in combination with the compounds capable of generating an acid by light. Among the compounds that decompose to generate an acid upon irradiation with actinic rays or radiation, those that are particularly effectively used include the following general formula (PAG3), general formula (PAG4), general formula (PAG6), or general formula (PAG6). The compound shown by PAG7) can be mentioned.

[0051]

[Chemical 17]

In the general formulas (PAG3) and (PAG4), A
r ¹ and Ar ² are the same or different and each represents a substituted or unsubstituted aryl group. Preferable substituents include an alkyl group, a haloalkyl group, a cycloalkyl group, an aryl group, an alkoxy group, a nitro group, a carboxyl group, an alkoxycarbonyl group, a hydroxy group, a mercapto group and a halogen atom. R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ are
The same or different, substituted or unsubstituted alkyl group,
Indicates an aryl group. Of these, an aryl group having 6 to 14 carbon atoms, an alkyl group having 1 to 8 carbon atoms, and a substituted derivative thereof are preferable. Preferred substituents are an alkoxy group having 1 to 8 carbon atoms, an alkyl group having 1 to 8 carbon atoms, a nitro group, a carboxyl group, a hydroxy group and a halogen atom for the aryl group, and an alkyl group for the alkyl group. Carbon number 1
To alkoxy groups, carboxyl groups, and alkoxycarbonyl groups.

Z ⁻ represents a counter anion, for example, BF ₄ ⁻ ,
_{^{AsF 6 -, PF 6 -,}} SbF 6 -, SiF 6 2-, ClO 4 -,
Alkane sulfonic acid that may be substituted, perfluoroalkane sulfonic acid, benzene sulfonic acid that may be substituted, naphthalene sulfonic acid, anthracene sulfonic acid,
Examples thereof include camphor sulfonic acid, but are not limited thereto. Preferred are alkanesulfonic acid, perfluoroalkanesulfonic acid, alkyl-substituted benzenesulfonic acid, and pentafluorobenzenesulfonic acid. Two of R ²⁰³ , R ²⁰⁴ , and R ²⁰⁵ and Ar ¹ and Ar ^{2 are also included.}
May be bonded via their respective single bonds or substituents.

R in the general formulas (PAG6) and (PAG7)
²⁰⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, or arylene group. R represents a linear, branched or cyclic alkyl group or an aryl group which may be substituted. Specific examples thereof include the compounds shown below, but the invention is not limited thereto.

[0055]

[Chemical 18]

[0056]

[Chemical 19]

[0057]

[Chemical 20]

[0058]

[Chemical 21]

[0059]

[Chemical formula 22]

[0060]

[Chemical formula 23]

In the present invention, the photoacid generator used in combination is preferably one represented by the above formula (PAG-7). These photoacid generators that can be used in combination are used in an amount of 5% by weight or less, preferably 2% by weight or less, based on the solid content of the composition.

<Resin (B) Decomposed by Action of Acid to Increase Solubility in Alkaline Developer> Resin (B) used in the composition of the present invention that decomposes by action of acid (B) to increase solubility in an alkali developer ( Hereinafter, the "resin of (B)") contains at least one repeating unit selected from the above general formulas (1) and (2).

In the general formula (1), R₁Is an alkyl group or
Represents an acid-decomposable group. m represents an integer of 0-4. n is
Represents an integer of 0-10. multiple when n is an integer of 2 or more
R ₁May be the same or different. General formula (2)
Medium, R₂And R₃Are the same or different, hydrogen
Atom, alkyl group, cycloalkyl group or acid-eliminating property
Represents a guardian.

In the general formula (1), examples of the alkyl group represented by R ₁ include linear and branched alkyl groups, which may have a substituent. As the linear or branched alkyl group, a linear or branched alkyl group having 1 to 5 carbon atoms is preferable, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, Examples thereof include isobutyl group, sec-butyl group, t-butyl group, pentyl group and the like.

Examples of the alkyl group represented by R ₂ and R _{3 in} the general formula (2) include linear and branched alkyl groups, which may have a substituent. As the linear or branched alkyl group, a linear or branched alkyl group having 1 to 12 carbon atoms is preferable, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, and an n-butyl group. Examples thereof include isobutyl group, sec-butyl group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group and decyl group. The cycloalkyl group is preferably a cycloalkyl group having a carbon number of 3 to 20, and examples thereof include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a 2-methyladamantyl group, a norbornyl group, Examples thereof include an isobornyl group, a dicyclopentyl group and a tricyclodecanyl group.

In the resin (B) according to the present invention, the acid-decomposable group is a hydrophilic group such as a carboxyl group protected by an acid-eliminating protective group, and the protective group is protected by the action of an acid. When the resin (B) is desorbed and becomes hydrophilic, the solubility of the resin (B) in an alkaline aqueous solution is increased. In the resin (B) according to the present invention, the acid-decomposable group is preferably a carboxylic acid tertiary alkyl ester group, a carboxylic acid acetal ester group, or the like.

In the resin according to the present invention, the structure of the acid-decomposable group is represented by, for example, —C (═O) —X ₁ —R ₀ . In the formula, R ₀ is a tertiary alkyl group such as t-butyl group, t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxy group. 1-such as ethyl group
Alkoxyethyl group, alkoxymethyl group such as 1-methoxymethyl group, 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3-oxocyclohexyl ester group, 2 Examples include -methyl-2-adamantyl group and mevalonic lactone residue. X ₁ is an oxygen atom, a sulfur atom, -NH-, -NHS.
Represents O ₂ — or —NHSO ₂ NH—.

Examples of the acid-eliminating protecting group in the general formula (2) include the same groups as R ₀ , that is, tertiary alkyl groups such as t-butyl group and t-amyl group, Isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group,
1-isobutoxyethyl group, 1-alkoxyethyl group such as 1-cyclohexyloxyethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group,
3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group,
3-oxocyclohexyl ester group, 2-methyl-2
Examples thereof include an adamantyl group and a mevalonic lactone residue.

Examples of the monomer corresponding to the repeating unit represented by the general formula (1) include 2-methylene-3-propanolide, 2-methylene-5-pentanolide, 2-methylene-6-hexanolide, 2- Methylene-7-heptanolide, 2-methylene-butyrolactone, 4-methyl-
2-methylene-butyrolactone, 4-ethyl-2-methylene-butyrolactone, 4-isopropyl-2-methylene-butyrolactone, 2-methylene-4,4-dimethyl-butyrolactone and the like can be mentioned.

Examples of the monomer corresponding to the repeating unit represented by the general formula (2) include di (alkyl) -2,
Mention may be made of 2 '-[oxybis (methylene)] bis-2-propenoates. Di (alkyl) -2,
Examples of the alkyl group in 2 ′-[oxybis (methylene)] bis-2-propenoate include the same alkyl groups and cycloalkyl groups as R ₂ and R _{3 in} the general formula (2). You can

The resin (B) in the present invention preferably further has a repeating unit represented by the following general formula (pA).

[0072]

[Chemical formula 24]

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 R may be the same or different. A is 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, or a urea group, alone or in combination of two or more. Represents a combination of groups. Ra represents any group of the following formulas (pI) to (pVI).

[0074]

[Chemical 25]

In the formula, R ₁₁ is a methyl group, an ethyl group or n-
It represents a propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a 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 of 1 to 4 carbon atoms, represents a linear or branched alkyl group or alicyclic hydrocarbon group, provided that at least one of R ₁₂ to R _14, or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group. R ₁₇
To R ₂₁ are each independently a hydrogen atom, a C 1 to C 4,
It represents a linear or branched alkyl group or an alicyclic hydrocarbon group, 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 having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. R _{22 to} R ₂₅ each independently represent 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 is an aliphatic group. Represents a cyclic hydrocarbon group. Also, R ₂₃ and R
₂₄ may combine with each other to form a ring. )

Specific examples of the monomer corresponding to the repeating unit represented by the general formula (pA) are shown below.

[0077]

[Chemical formula 26]

[0078]

[Chemical 27]

[0079]

[Chemical 28]

[0080]

[Chemical 29]

[0081]

[Chemical 30]

[0082]

[Chemical 31]

The acid-decomposable resin as the component (B) of the present invention preferably contains a repeating unit having a lactone structure. For example, it preferably contains a repeating unit represented by the following general formula (IV).

[0084]

[Chemical 32]

In formula (IV), R ₁ a represents a hydrogen atom or a methyl group. W ₁ represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, or a combination of two or more groups selected from the group consisting of. Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , Re ₁
Each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m and n each independently represent an integer of 0 to 3, and m +
n is 2 or more and 6 or less.

Examples of the alkyl group having 1 to 4 carbon atoms represented by Ra _{1 to} Re ₁ include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group and the like. Can be mentioned.

In the general formula (IV), examples of the alkylene group for W ₁ include groups represented by the following formula. - [C (Rf) (Rg)] r ₁ - In the above formulas, Rf, R
g represents a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group or an alkoxy group, and they may be the same or different. As the alkyl group, a methyl group,
A lower alkyl group such as an ethyl group, a propyl group, an isopropyl group and a butyl group is preferable, and a methyl group is more preferable.
It is selected from ethyl group, propyl group and 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 those having 1 to 4 carbon atoms such as methoxy group, ethoxy group, propoxy group and butoxy group. As a halogen atom, a chlorine atom, a bromine atom,
Examples thereof include a fluorine atom and an iodine atom. r ₁ is an integer of ₁ to 10.

Examples of the further substituent in the above alkyl group include a carboxyl group, an acyloxy group, a cyano group, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a substituted alkoxy group, an acetylamide group, an alkoxycarbonyl group, An acyl group can be mentioned. 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 substituent of the substituted alkoxy group include an alkoxy group and the like. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as methoxy group, ethoxy group, propoxy group and butoxy group. An acetoxy group etc. are mentioned as an acyloxy group. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom, iodine atom and the like.

Specific examples of the monomer corresponding to the repeating structural unit represented by the general formula (IV) are shown below, but the present invention is not limited thereto.

[0090]

[Chemical 33]

[0091]

[Chemical 34]

[0092]

[Chemical 35]

In the specific example of the above general formula (IV), since the exposure margin becomes better, (IV-1
7) to (IV-36) are preferable. Further, as the structure of the general formula (IV), a structure having an acrylate structure is preferable from the viewpoint of good edge roughness.

Further, the following general formulas (V-1) to (V-4)
It is also preferable to contain a repeating unit having a group represented by any of the above.

[0095]

[Chemical 36]

In the general formulas (V-1) to (V-4),
R _{1b to} R _5b each independently represent a hydrogen atom or an optionally substituted alkyl group, cycloalkyl group or alkenyl group. Two of R _{1b to} R _5b may combine with each other to form a ring.

In the general formulas (V-1) to (V-4),
Examples of the alkyl group for R _{1b to} R _5b include linear and branched alkyl groups, which may have a substituent. The linear or branched alkyl group has 1 to 1 carbon atoms.
12 straight chain or branched alkyl groups are preferred,
More preferably, it is a linear or branched alkyl group having 1 to 10 carbon atoms, and even more preferably, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t. -Butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group,
It is a decyl group. The cycloalkyl group for R _{1b to} R _5b is preferably a cycloalkyl group having 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a cyclooctyl group. The alkenyl group in R _{1b to} R _5b is preferably an alkenyl group having a carbon number of 2 to 6, such as a vinyl group, a propenyl group, a butenyl group and a hexenyl group. Examples of the ring formed by combining two members out of R _{1b to} R _5b include a 3- to 8-membered ring such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring. The general formula (V-1)
R _{1b to} R _5b in to (V-4) may be bonded to any of the carbon atoms constituting the cyclic skeleton.

Preferred substituents which the above alkyl group, cycloalkyl group and alkenyl group may have are an alkoxy group having 1 to 4 carbon atoms, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine). Atom), an acyl group having 2 to 5 carbon atoms, an acyloxy group having 2 to 5 carbon atoms, a cyano group, a hydroxyl group, a carboxy group, an alkoxycarbonyl group having 2 to 5 carbon atoms, a nitro group and the like.

The repeating unit having a group represented by any of the general formulas (V-1) to (V-4) is represented by the following general formula (AI).
The repeating unit represented by

[0100]

[Chemical 37]

In formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. Preferable substituents that the alkyl group represented by R _b0 may have include those represented by the general formula (V-1) to
Examples of the preferable substituent that the alkyl group as R _1b in (V-4) may have include those exemplified above. Examples of the halogen atom of R _b0 include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R
_b0 is preferably a hydrogen atom. A'represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group combining these. B ₂ represents a group represented by any one of formulas (V-1) to (V-4). In A ′, examples of the combined divalent group include those represented by the following formulas.

[0102]

[Chemical 38]

In the above formula, Rab and Rbb represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group or an alkoxy group, and they 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 and butyl group, and more preferably selected from methyl group, ethyl group, propyl group and isopropyl group. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group having 1 to 4 carbon atoms. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as methoxy group, ethoxy group, propoxy group and butoxy group. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom, iodine atom and the like. r
1 represents an integer of 1 to 10, preferably an integer of 1 to 4.
m represents an integer of 1 to 3, preferably 1 or 2.

Specific examples of the repeating unit represented by formula (AI) are shown below, but the contents of the present invention are not limited thereto.

[0105]

[Chemical Formula 39]

[0106]

[Chemical 40]

[0107]

[Chemical 41]

[0108]

[Chemical 42]

[0109]

[Chemical 43]

[0110]

[Chemical 44]

[0111]

[Chemical formula 45]

The acid-decomposable resin as the component (B) of the present invention preferably contains a repeating unit represented by the following general formula (VI).

[0113]

[Chemical formula 46]

In the general formula (VI), A ₆ is a single bond,
It represents a single group or a combination of two or more groups selected from the group consisting of 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 the general formula (VI), examples of the alkylene group represented by A ₆ include groups represented by the following formula. -[C (Rnf) (Rng)] r- In the above formula, Rnf and Rng are each a hydrogen atom, an alkyl group,
It represents a substituted alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group, and they 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 and butyl group, and more preferably selected from methyl group, ethyl group, propyl group and 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 those having 1 to 4 carbon atoms such as methoxy group, ethoxy group, propoxy group and butoxy group. Examples of the halogen atom include chlorine atom, bromine atom, fluorine atom, iodine atom and the like. r is an integer of 1-10. General formula (V
In I), the cycloalkylene group represented by A ₆ includes those having 3 to 10 carbon atoms, and examples thereof include a cyclopentylene group, a cyclohexylene group, and a cyclooctylene group.

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 (eg, formyl group, benzoyl group), an acyloxy group ( For example, propyl carbonyloxy group, benzoyloxy group), an alkyl group (preferably having from 1 to 4 carbon atoms), a carboxyl group, a hydroxyl group and an alkylsulfonylsulfamoyl group (-CONHSO ₂ CH _3, etc.). still,
The alkyl group as a substituent may be further substituted with a hydroxyl group, a halogen atom, an alkoxy group (preferably having a carbon number of 1 to 4) or the like.

In the general formula (VI), the oxygen atom of the ester group bonded to A ₆ may be bonded at any position of the carbon atoms constituting the bridged alicyclic structure containing Z _6. Good.

The specific examples of the repeating units represented by formula (VI) are shown below, but the invention is not limited thereto.

[0119]

[Chemical 47]

[0120]

[Chemical 48]

Further, a repeating unit having a group represented by the following general formula (VII) may be contained.

[0122]

[Chemical 49]

[0123] In the general formula _{(VII), R 2 c~R 4} c represents a hydrogen atom or a hydroxyl group independently. However, R ₂ c to R ₄ c
At least one of them represents a hydroxyl group.

The group represented by the general formula (VII) is preferably a dihydroxy body or a monohydroxy body, more preferably a dihydroxy body.

Examples of the repeating unit having a group represented by the general formula (VII) include a repeating unit represented by the following general formula (AII).

[0126]

[Chemical 50]

In formula (AII), R ₁ c represents a hydrogen atom or a methyl group. R ₂ c to R ₄ c represents a hydrogen atom or a hydroxyl group independently. Provided that at least one of R ₂ c to R ₄ c represents a hydroxyl group.

The specific examples of the repeating units having the structure represented by formula (AII) are shown below, but the invention is not limited thereto.

[0129]

[Chemical 51]

In addition to the above, the resin (B) controls dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and resolution, heat resistance, sensitivity, etc., which are general requirements for resists. It can be used as a copolymer with various monomer repeating units for the purpose.

Examples of such repeating units include, but are not limited to, repeating units corresponding to the following monomers. Thereby, the performance required for the resin, particularly (1) solubility in a coating solvent, (2) film-forming property (glass transition point), (3)
Alkali developability, (4) Membrane slippage (hydrophobicity, selection of alkali-soluble groups), (5) Adhesion of unexposed area to substrate,
(6) It is possible to finely adjust the dry etching resistance.
Examples of such copolymerizable monomers include addition polymerizable unsaturated bonds selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and the like. The compound etc. which have one can be mentioned.

Specifically, for example, acrylic acid esters such as alkyl (wherein the alkyl group has 1 to 1 carbon atoms).
0) is preferred) Acrylate (eg, 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 etc.);

Methacrylic acid esters such as alkyl (alkyl groups having 1 to 10 carbon atoms are preferred) methacrylate (eg methyl methacrylate,
Ethylmethacrylate, propylmethacrylate, isopropylmethacrylate, amylmethacrylate, hexylmethacrylate, cyclohexylmethacrylate,
Benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate,
5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, etc.); acrylamides such as acrylamide, N-alkylacrylamide , (Alkyl group has 1 to 1 carbon atoms
0, for example, methyl group, ethyl group, propyl group, butyl group, t-butyl group, heptyl group, octyl group, cyclohexyl group, hydroxyethyl group and the like. ), N,
N-dialkyl acrylamide (alkyl group having 1 to 10 carbon atoms, such as methyl group, ethyl group,
There are butyl group, isobutyl group, ethylhexyl group, cyclohexyl group and the like. ), N-hydroxyethyl-N-methylacrylamide, N-2-acetamidoethyl-N
-Acetylacrylamide etc .;

Methacrylamides, such as methacrylamide, N-alkylmethacrylamides (alkyl groups having 1 to 10 carbon atoms, such as methyl, ethyl, t-butyl, ethylhexyl, hydroxyethyl, cyclohexyl). Groups, etc.), N, N-dialkylmethacrylamides (such as ethyl groups, propyl groups, and butyl groups as alkyl groups), N-hydroxyethyl-N-methylmethacrylamide, etc .; allyl compounds such as allyl esters ( For example, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, etc.), allyloxyethanol, etc .; vinyl ethers such as alkyl vinyl ethers (eg, Hex Vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl 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, etc.);

Vinyl esters such as vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl barrate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxyacetate, vinyl butoxyacetate, Vinyl acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinylcyclohexylcarboxylate, etc .; dialkyl itaconates (eg dimethyl itaconic acid, diethyl itaconic acid, dibutyl itaconic acid etc.); dialkyl esters of fumaric acid (eg dibutyl Fumarate etc.) or monoalkyl esters; other acrylic acid, methacrylic acid,
Examples thereof include crotonic acid, itaconic acid, maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, and maleironitrile. In addition, addition polymerizable unsaturated compounds copolymerizable with the above various repeating units may be used.

In the resin (B), the content molar ratio of each repeating unit structure is such that the acid value, the dry etching resistance of the resist, the suitability for a standard developing solution, the substrate adhesion, the density dependence of the resist profile, and the general resist composition. It is appropriately set in order to adjust the resolving power, heat resistance, sensitivity, etc. that are specifically required.

In the resin (B), the compounds represented by the general formulas (1) and (2)
The content of at least one repeating unit selected from the above is usually 0.1 to 50 mol%, preferably 1.0 to 40 mol%, and more preferably 2.0 to 30 in all repeating units. Mol%.

In the resin (B), the content of the repeating unit represented by the general formula (pA) is 30 to 30% based on all repeating units.
70 mol% is preferable, 35-65 mol% is more preferable, and 40-60 mol% is still more preferable.

The weight average molecular weight Mw of the resin (B) is a polystyrene standard by gel permeation chromatography, preferably 1,000 to 1,000,
000, more preferably 1,500 to 500,000,
It is more preferably in the range of 2,000 to 200,000, and particularly preferably in the range of 2,500 to 100,000. The higher the weight average molecular weight, the higher the heat resistance and the like, but the lower the developability and the like. The balance is adjusted to a preferable range.

The resin (B) used in the present invention can be synthesized by a conventional method, for example, a radical polymerization method.

In the positive resist composition for deep-UV exposure of the present invention, the addition amount of the resin (B) in the entire composition is preferably 40 to 99.99% by weight, more preferably total resist solid content. It is 50 to 99.97% by weight.

In the positive resist composition of the present invention, if necessary, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer,
A surfactant, a photosensitizer, an organic basic compound, a compound that promotes solubility in a developing solution, and the like can be contained.

The positive photoresist composition of the present invention comprises
It is preferable to contain a surfactant, and it is particularly preferable to contain a fluorine-based surfactant or a silicon-based surfactant.

That is, it is particularly preferable to contain one of the fluorine-based surfactant and the silicon-based surfactant, or the fluorine-based surfactant and the silicon-based surfactant.
Here, the fluorine-based surfactant may be a surfactant that simultaneously contains silicon atoms in addition to fluorine atoms. Further, the silicon-based surfactant may contain a fluorine atom together with a silicon atom. Examples of these surfactants include JP-A-62-36663, JP-A-61-226746, and JP-A-61-226745.
No. 62-170950, 63-345.
40, JP-A-7-230165, and JP-A-8-628.
34, JP-A-9-54432, and JP-A-9-5988.
The surfactants described in No. 1 can be mentioned, and the following commercially available surfactants can be used as they are. Examples of commercially available surfactants that can be used include Ftop EF301,
EF303, (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC
430, 431 (manufactured by Sumitomo 3M Limited), Megafac F171, F173, F176, F189, R08.
(Manufactured by Dainippon Ink and Chemicals, Inc.), Surflon S-382, S
C101, 102, 103, 104, 105, 106
(Asahi Glass Co., Ltd.) fluorine-based surfactants or silicon-based surfactants. Polysiloxane polymer KP-341 (produced by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

The content 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 combinations.

Specific examples of the surfactant that can be used in addition to the above include polyoxyethylene such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether and polyoxyethylene oleyl ether. Alkyl ethers, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether and other polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate , Sorbitan monooleate, sorbitan trioleate, sorbitan tristearate and other sorbitan fatty acid esters, polyoxyethylene Nonionics such as polyoxyethylene sorbitan fatty acid esters such as bitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate A surfactant and the like can be mentioned. The amount of these other surfactants to be added is usually 2 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the solid content in the composition of the present invention.

The acid diffusion inhibitor (C) which can be used in the present invention is preferably added from the viewpoint of suppressing fluctuations in sensitivity and resolution with the lapse of time after heating after exposure and development, and a basic compound, Organic basic compounds are preferred. Examples of the organic basic compound include nitrogen-containing basic compounds having the following structures.

[0148]

[Chemical 52]

Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² are the same or different and each is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, or a hydroxyalkyl having 1 to 6 carbon atoms. Or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, wherein R ²⁵¹ and R
²⁵² may combine with each other to form a ring.

[0150]

[Chemical 53]

(Wherein R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶
Are the same or different and each represents an alkyl group having 1 to 6 carbon atoms.) A more preferable compound is a nitrogen-containing basic compound having two or more nitrogen atoms of different chemical environments in one molecule,
Particularly preferred is a compound containing both a substituted or unsubstituted amino group and a ring structure containing a nitrogen atom, or a compound 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 indazole, 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 An alkyl morpholine etc. are mentioned. Preferred substituents are amino groups, aminoalkyl groups, alkylamino groups, aminoaryl groups, arylamino groups, alkyl groups, alkoxy groups, acyl groups, acyloxy groups, aryl groups, aryloxy groups, nitro groups,
A hydroxyl group and a cyano group.

Preferred specific compounds include 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-amino Pyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-imino Piperidine, 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] non-5-ene, 1,8
-Diazabicyclo [5,4,0] undec-7-ene,
3,4,5-triphenylimidazole, N-methylmorpholine, N-ethylmorpholine, N-hydroxyethylmorpholine, N-benzylmorpholine, cyclohexylmorpholinoethylthiourea (CHMETU) and the like 3
Grade morpholine derivatives, hindered amines described in JP-A No. 11-52575 (for example, the publication [0005]
And the like) but are not limited thereto.

Particularly preferred specific examples are 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] -7-undecene and 1,4-diazabicyclo [2]. 2.2.2] Octane, 4-dimethylaminopyridine, hexamethylenetetramine, 4,4-dimethylimidazoline, pyrroles, pyrazoles, imidazoles, pyridazines, pyrimidines, CHMETU
And tertiary hindered amines such as bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate. 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) sebacate is preferred.

In the positive resist composition of the present invention, the most preferable basic compound is an alkylamine structure, an alkylamine structure having an ether bond, an alkylamine structure having a hydroxyl group, an aniline structure, a pyridine structure, a diazabicyclo structure. And a compound having at least one structure selected from the group consisting of ammonium hydroxide structure, ammonium carboxylate structure and imidazole structure. Here, the alkylamine structure having an ether structure may be a structure which simultaneously contains a hydroxyl group in addition to an ether bond. Further, the alkylamine structure having a hydroxyl group may be a structure containing an ether structure together with a hydroxyl group.

These nitrogen-containing basic compounds may be used alone or in combination of two or more. The nitrogen-containing basic compound is used in an amount of usually 0.001 to 10% by weight, preferably 0.01 to 5% by weight, based on the total solid content of the photosensitive resin composition. If it is less than 0.001% by weight, the effect of adding 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 area tends to deteriorate.

The positive resist composition of the present invention is dissolved in a solvent which dissolves each of the above components and coated 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, the preferred solvent is 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, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, methoxypropionic acid Mention may be made of methyl, ethyl ethoxypropionate, N-methylpyrrolidone and tetrahydrofuran. It is also preferable to mix two or more solvents, and particularly preferably a mixed solvent of a solvent not containing a hydroxyl group and a solvent containing a hydroxyl group.

The positive resist composition of the present invention is coated on a substrate to form a thin film. The thickness of this coating film is preferably 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 antireflection film, an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon and α-silicon, and an organic film type composed of a light absorber and a polymer material can be used. The former requires equipment such as a vacuum vapor deposition apparatus, a CVD apparatus, and a sputtering apparatus for forming a film. Examples of the organic antireflection film include Japanese Patent Publication No. 7-
What is composed of a condensate of a diphenylamine derivative and a formaldehyde-modified melamine resin described in 69611, an alkali-soluble resin and a light absorber, a reaction product of a maleic anhydride copolymer and a diamine type light absorber described in US Pat. No. 5,294,680. A resin containing the resin binder described in 118631 and a methylol melamine-based thermal cross-linking agent.
-118656, an acrylic resin type antireflection film having a carboxylic acid group, an epoxy group and a light-absorbing group in the same molecule, comprising a methylol melamine and a benzophenone-based light-absorbing agent described in JP-A-8-87115, and JP-A-8-17950.
Examples of the polyvinyl alcohol resin described in 9 include a low molecular weight light absorber. In addition, as the organic antireflection film, DUV30 series and DUV-40 series manufactured by Brewer Science Co., AC-2 manufactured by Shipley Co.,
AC-3 etc. can also be used.

The resist solution is applied to a substrate (eg, a silicon / silicon dioxide coating) used for manufacturing precision integrated circuit devices (eg, a substrate optionally provided with the antireflection film), a spinner, and a coater. A good resist pattern can be obtained by applying a suitable coating method such as the above, exposing through a predetermined mask, baking and developing. 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), F2 excimer laser (157
nm), X-rays, electron beams and the like.

As the developing solution, 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, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like. It is possible to use an alkaline aqueous solution of a quaternary ammonium salt, a cyclic amine such as pyrrole, or a pyrhelidine. Furthermore, alcohols and surfactants may be added in appropriate amounts to the alkaline aqueous solution before use.

[0161]

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[Synthesis of Photoacid Generator as Component (A)] Two examples of synthesis of the photoacid generator as Component (A) are shown below. Other photoacid generators used below Was synthesized by a similar method, the above-mentioned general method, or a commercially available one was used. The following photo-acid generator was manufactured by Midori Kagaku Co., Ltd. Triphenylsulfonium perfluoro-n-butane sulfonate: (A1-1) bis (t-butylphenyliodonium) perfluoro-
n-Butane sulfonate: (A1-49)

(Triphenylsulfonium perfluoro-
Synthesis of n-octane sulfonate (A1-3)) Diphenyl sulfoxide (50 g) was dissolved in benzene (800 ml), and aluminum chloride (200 g) was added thereto.
Refluxed for 4 hours. The reaction solution was slowly poured into 2 L of water, 400 ml of concentrated hydrochloric acid was added, and the mixture was heated at 70 ° C for 10 minutes. The aqueous solution was washed with 500 ml of ethyl acetate, filtered, and then 200 g of ammonium iodide dissolved in 400 ml of water was added. The precipitated powder was collected by filtration, washed with water, washed with ethyl acetate, and dried to obtain 70 g of triphenylsulfonium iodide. Triphenylsulfonium iodide (17.6 g) was dissolved in methanol (1000 ml), and silver oxide (12.5 g) was added to this solution.
Stir for hours. The solution was filtered, and 25 g of perfluoro-n-octanesulfonic acid in methanol was added thereto.
The reaction solution was concentrated, the precipitated oily substance was dissolved in ethyl acetate, washed with water, dried and concentrated to obtain 20.5 g of the desired product.

((Tri (t-butylphenyl) sulfonium perfluoro-n-butanesulfonate (A1-5)
Synthesis of di (t-butylphenyl) sulfide (80 mmo
1), a mixture of di (t-butylphenyl) iodonium perfluoro-n-butanesulfonate (20 mmo1) and copper benzoate (4 mmo1) at 130 ° C. under a nitrogen stream at 4 ° C.
Stir for hours. The reaction solution was allowed to cool and ethanol 10 was added to it.
0 ml was added and the precipitate was removed. The filtrate was concentrated, and 200 ml of ether was added to this to precipitate a powder, which was collected by filtration, washed with ether and dried to obtain the desired product.

[Synthesis of Resin as Component (B)] (Synthesis of Resin (2)) 2-Adamantyl-2-propylmethacrylate, 2-
Charge methylene butyrolactone and dihydroxy adamantane methacrylate in a weight ratio of 40/40/20, and add P
Dissolved in GMEA (propylene glycol monomethyl ether acetate) / PGME (propylene glycol monomethyl ether) = 7/3, solid concentration 22% by weight
450 g of the above solution was prepared. Wako Pure Chemical Industries V-
601 was added in an amount of 1 mol%, and this was heated to 100 ° C. for 6 hours in a nitrogen atmosphere. PGMEA (propylene glycol monomethyl ether acetate) / PGME (propylene glycol monomethyl ether) = 7/3, 40
g. After completion of dropping, the reaction solution was stirred for 4 hours.
After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 liters of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration. The resin (2), which was a target substance, was recovered by reslurrying. Polymer composition ratio determined by NMR is 43/21 /
It was 36. Moreover, the weight average molecular weight in terms of standard polystyrene determined by GPC measurement was 10300.
Resins (1) to (21) having the repeating unit shown below and having the repeating unit (molar ratio) and the molecular weight shown in Table 1 were synthesized by the same operation as in this synthesis example. The repeating unit of each resin and the repeating unit (molar ratio) in Table 1 correspond in the order from the left.

The repeating units of resins (1) to (21) are shown below.

[0167]

[Chemical 54]

[0168]

[Chemical 55]

[0169]

[Chemical 56]

[0170]

[Chemical 57]

[0171]

[Table 1]

Examples 1 to 21 and Comparative Examples 1 to 3 [Preparation and Evaluation of Photosensitive Composition] The resin synthesized in the above Synthesis Example and each component shown in Table 2 are shown in Table 2 at a solid content of 12% by weight. After being dissolved in the solvent described in 1., the positive resist compositions of Examples 1 to 21 and Comparative Examples 1 to 3 were prepared by filtering with a 0.1 μm microfilter. Table 2 shows each component of the positive resist composition used in the present invention.

[0173]

[Table 2]

Each symbol in Table 2 shows the following. [Resin] Resin Z: 2-methyl-2-adamantyl methacrylate mevalonic lactone methacrylate (50/5
0), weight average molecular weight 6900 [acid diffusion inhibitor] B1: DBN; 1,5-diazabicyclo [4.3.0]
Nona-5-ene B2: TPI; 2,4,5-triphenylimidazole B3: DCMA; Dicyclohexylmethylamine B4: 2,6-diisopropylaniline B5: TPSA; Triphenylsulfonium acetate B6: Tri-n-octylamine B7 : Tri-n-butylamine B8: hydroxyantipyrine B9: tetrabutylammonium hydroxide B10: tris (methoxyethoxyethyl) amine

[Surfactant] W1: Megafac F176 (manufactured by Dainippon Ink and Chemicals, Inc.)
(Fluorine type) W2: Megafac R08 (manufactured by Dainippon Ink and Chemicals, Inc.)
(Fluorine and silicon type) W3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (Silicone type) W4: Troisol S-366 (Troy Chemical Co., Ltd.)
Made)

[Solvent] PGMEA: Propylene glycol monomethyl ether acetate PGME: Propylene glycol monomethyl ether CH: Cyclohexanone BL: γ-butyrolactone EL: Ethyl lactate EEP: Ethylethoxypropionate

<Image Evaluation Method> Evaluation of Resolving Power and Dependence of Density / Denseness On a silicon substrate treated with hexamethyldisilazane by a spin coater, an antireflection film DUV-42 manufactured by Brewer Science Co., Ltd. is uniformly applied at 600 angstrom, and 100 After drying on a hot plate at 90 ° C. for 90 seconds, heat drying was performed at 190 ° C. for 240 seconds. afterwards,
Each photosensitive resin composition is applied with a spin coater and the temperature is 120 ° C.
And dried for 90 seconds to form a 0.3 μm resist film. An ArF excimer laser stepper (NA = 0.6 manufactured by ISI) is passed through the resist film through a mask.
And then immediately heated on a hot plate at 120 ° C. for 90 seconds. Further, it was developed with a 2.38% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds and then dried to obtain a resist line pattern.

[Resolving power]: The resolving power shows a limiting resolving power at an exposure dose for reproducing a mask pattern of 0.13 μm. [Dense / dense dependence] Line and space pattern with line width 0.13 μm (Dense pattern: line and space 1 /
1) and an isolated line pattern (sparse pattern: line and space 1/5), each 0.13 μm ± 1
The overlapping range of the depth of focus that allowed 0% was obtained. The larger this range is, the better the density dependence is. The results are shown in Table 3.

[0179]

[Table 3]

As is clear from the results shown in Table 3, the positive resist composition of the present invention is at a satisfactory level for all of them. That is, it is suitable for lithography using deep ultraviolet rays such as ArF excimer laser exposure.

[0181]

INDUSTRIAL APPLICABILITY The present invention can provide a positive resist composition which is suitable for far ultraviolet light, particularly ArF excimer laser light, and is excellent in resolution and dependency of density.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 37/00 C08L 37/00 G03F 7/004 501 G03F 7/004 501 503 503A H01L 21/027 H01L 21 / 30 502R F Term (reference) 2H025 AA02 AB16 AC04 AC08 AD03 BE00 BE07 BG00 CC20 FA03 FA12 FA17 4J002 BG001 BG041 BQ001 EV236 FD206 GP00 4J100 AJ03P AL69P AL71P AU29P BA02P BC02P CA01 CA03 CA04 CA05 CA06 JA38

Claims (4)

[Claims] 1. (A) By irradiation with actinic rays or radiation
To generate fluorine-substituted sulfonic acid having 2 or more carbon atoms
Compound and (B) selected from the following general formulas (1) and (2)
Action of acid containing at least one repeating unit
Decomposes by increasing the solubility in alkaline developers
Positive resist composition containing a resin
Stuff. [Chemical 1] R in the general formula (1)₁Is an alkyl group or an acid-decomposable group
Represent m represents an integer of 0-4. n is an integer from 0 to 10
Represents a number. When n is an integer of 2 or more, a plurality of R ₁Is the same
It may be the same or different. R in the general formula (2)₂as well as
R₃May be the same or different and may be a hydrogen atom,
Represents a kill group, cycloalkyl group or acid-eliminating protecting group.
You 2. The positive resist composition according to claim 1, wherein the compound of the component (A) is a sulfonium salt. 3. The positive resist composition according to claim 1, further comprising a basic compound and a fluorine-based surfactant or a silicon-based surfactant. 4. The basic compound is an alkylamine structure,
A compound having at least one structure selected from an alkylamine structure having an ether bond, an alkylamine structure having a hydroxyl group, an aniline structure, a pyridine structure, a diazabicyclo structure, an ammonium hydroxide structure, an ammonium carboxylate structure and an imidazole structure. The positive resist composition according to claim 3, wherein