JP2001013688A - Radiation sensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a radiation sensitive resin composition excellent in physical properties such as transparency to radiation, dry etching resistance, sensitivity and resolution, shelf stability and adhesion by incorporating a specified alkali- insoluble or slightly alkali-soluble resin which is made alkali-soluble when an acid dissociable group is dissociated and a radiation sensitive acid generating agent. SOLUTION: The radiation sensitive resin composition contains an alkali- insoluble or slightly alkali-soluble acid dissociable group-containing resin which is made alkali-soluble when the acid dissociable group is dissociated and a radiation sensitive acid generating agent. The resin is selected from a copolymer having repeating units of formulae I, II and III-1 and a copolymer having repeating units of formulae I, II and III-2. In the formulae, A and B are each H or a <=20C acid dissociable organic group which is dissociated in the presence of an acid to form an acidic functional group, at least one of A and B is an acid dissociable organic group, X and Y are each H or a 1-4C alkyl, R1 is H, methyl or the like and R2 and R3 are each a di- or trivalent hydrocarbon group having an alicyclic group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation-sensitive resin composition, and more particularly, to charged particles such as far-ultraviolet rays such as KrF excimer laser or ArF excimer laser, X-rays such as synchrotron radiation, and electron beams. The present invention relates to a radiation-sensitive resin composition that can be suitably used as a chemically amplified resist useful for fine processing using various radiations such as lines.

[0002]

2. Description of the Related Art In the field of microfabrication represented by the manufacture of integrated circuit devices, lithography technology capable of microfabrication at a level of 0.20 μm or less has recently been required in order to obtain a higher degree of integration. Have been. However, in conventional lithography processes, i.
Near-ultraviolet rays such as lines are used, but it is said that it is extremely difficult to perform sub-quarter micron level fine processing with such near-ultraviolet rays. Therefore, in order to enable fine processing at a level of 0.20 μm or less, utilization of radiation having a shorter wavelength is being studied. As such short-wavelength radiation, for example, the emission line spectrum of a mercury lamp,
Examples include far ultraviolet rays represented by excimer lasers, X-rays, and electron beams. Of these, KrF
An excimer laser (wavelength 248 nm) or an ArF excimer laser (wavelength 193 nm) has attracted attention.
As such a radiation-sensitive resin composition suitable for irradiation with an excimer laser, a component having an acid-dissociable functional group and a component that generates an acid upon irradiation with radiation (hereinafter, referred to as “exposure”) (hereinafter, referred to as “acid”) Numerous compositions utilizing the chemical amplification effect of the compound (hereinafter referred to as “generator”) have been proposed (hereinafter referred to as “chemically amplified radiation-sensitive compositions”). As the chemically amplified radiation-sensitive composition, for example,
Japanese Patent No. 27660 proposes a composition containing a polymer having a t-butyl ester group of carboxylic acid or a t-butyl carbonate group of phenol and an acid generator. In this composition, the t-butyl ester group or t-butyl carbonate group present in the polymer is dissociated by the action of the acid generated by the exposure, and the polymer is formed of a carboxyl group or a phenolic hydroxyl group. This makes use of the phenomenon that the exposed region of the resist film becomes easily soluble in an alkali developing solution.

[0003] By the way, most of the conventional chemically amplified radiation-sensitive compositions are based on phenolic resins. In the case of such resins, when far ultraviolet rays are used as the radiation, the fragrance in the resins is reduced. Far ultraviolet rays are absorbed due to the aromatic ring, so there is a drawback that the exposed far ultraviolet rays cannot reach the lower layer portion of the resist film sufficiently.Therefore, the exposure amount is large in the upper layer portion of the resist film, and is lower in the lower layer portion. Thus, the resist pattern after development becomes trapezoidal as the upper part becomes thinner and the lower part goes to the lower part, resulting in a problem that a sufficient resolution cannot be obtained. In addition, when the resist pattern after development has a trapezoidal shape, desired dimensional accuracy cannot be achieved in the next step, ie, etching or ion implantation, which has been a problem. Moreover,
If the shape of the upper part of the resist pattern is not rectangular, there is a problem that the rate of disappearance of the resist by dry etching is increased, and it becomes difficult to control the etching conditions.
On the other hand, the shape of the resist pattern can be improved by increasing the radiation transmittance of the resist film. For example, (meth) represented by polymethyl methacrylate
Acrylate resins have high transparency to far ultraviolet rays and are very preferable from the viewpoint of radiation transmittance. For example, Japanese Patent Application Laid-Open No. Hei 4-226461 discloses a chemically amplified type resin using a methacrylate resin. Radiation resin compositions have been proposed. However, this composition
Although it is excellent in terms of fine processing performance, it does not have an aromatic ring and has the disadvantage of low dry etching resistance. In this case as well, it is difficult to perform high-precision etching processing, and it has high transparency to radiation. And dry etching resistance.

As one of measures for improving the dry etching resistance of a resist comprising a chemically amplified radiation-sensitive resin composition without impairing the transparency to radiation, aromatic resin is added to the resin component in the composition. A method of introducing an alicyclic ring in place of a ring is known.
JP-A-234511 proposes a chemically amplified radiation-sensitive resin composition using a (meth) acrylate resin having an alicyclic ring. However, in this composition, as the acid dissociable functional group of the resin component, a group that is relatively easily dissociated by a conventional acid (for example, an acetal-based functional group such as a tetrahydropyranyl group) or a compound that is relatively hard to be dissociated by an acid. Groups (for example, t-butyl-based functional groups such as a t-butyl ester group and a t-butyl carbonate group), and in the case of the former resin component having an acid dissociable functional group,
Although the basic physical properties of the resist, particularly the sensitivity and pattern shape, are good, there is a problem in the storage stability as a composition, and the former resin component having an acid dissociable functional group, on the contrary, has a good storage stability. However, there is a disadvantage in that the basic physical properties of the resist, particularly the sensitivity and the pattern shape, are impaired. Furthermore, since an alicyclic ring is introduced into the resin component in this composition, the hydrophobicity of the resin itself becomes extremely high, and there is a problem in the adhesiveness to the substrate. Therefore, it has high transparency to radiation represented by far ultraviolet rays, and is excellent not only in dry etching resistance, sensitivity, resolution, pattern shape, etc., but also in storage stability as a composition, and sufficient for a substrate. There is a demand for the development of a chemically amplified radiation-sensitive resin composition that maintains excellent adhesiveness.

[0005]

An object of the present invention is to provide an actinic radiation, for example, a KrF excimer laser or ArF.
As a chemically amplified resist that responds to far ultraviolet rays, typified by excimer lasers, it has high transparency to radiation, and has excellent basic physical properties as a resist such as dry etching resistance, sensitivity, resolution, and pattern shape. It is an object of the present invention to provide a radiation-sensitive resin composition which is excellent in the storage stability of the resin and has sufficient adhesiveness to a substrate.

[0006]

According to the present invention, the object is to provide (A) a repeating unit (I) represented by the following general formula (1):
And a copolymer having a repeating unit (II) and a repeating unit (III-1), and a repeating unit (I) represented by the following general formula (2)
And a repeating unit (II) and a repeating unit (III-2), selected from the group of copolymers having an acid-dissociable group-containing resin, wherein the acid-dissociable group is dissociated. Sometimes alkali-soluble resin, and (B)
A radiation-sensitive resin composition characterized by containing a radiation-sensitive acid generator,

[0007]

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[0008]

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[In the general formulas (1) and (2), A and B are each independently an acid-dissociable organic group having 20 or less carbon atoms which dissociates in the presence of a hydrogen atom or an acid to form an acidic functional group. X and Y are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n is 0.
R ¹ represents a hydrogen atom, a methyl group or a methylol group, and R ² has 3 to 3 carbon atoms having an alicyclic group.
15 represents a divalent hydrocarbon group, and R ³ represents a trivalent hydrocarbon group having 3 to 15 carbon atoms having an alicyclic group. ] Is achieved.

Hereinafter, the present invention will be described in detail. Component (A) In the present invention, the component (A) comprises a repeating unit (I), a repeating unit (II) and a repeating unit (II) represented by the general formula (1).
(I-1) as an essential constituent unit (hereinafter referred to as “copolymer (1)”) and the repeating unit (I) and the repeating unit (II) represented by the general formula (2). Repeating unit (II
An alkali-insoluble or sparingly alkali-soluble acid-dissociable group-containing resin selected from the group of copolymers containing I-2) as an essential constituent unit (hereinafter referred to as “copolymer (2)”). And a resin that becomes alkali-soluble when the acid-dissociable group is dissociated (hereinafter referred to as “resin (A)”). In the present invention, by containing the resin (A), a radiation-sensitive resin composition excellent in transparency to radiation and dry etching resistance, in particular, can be obtained as a resist.

The copolymer (1) and the copolymer (2) constituting the resin (A) are both substituted A and / or B in the repeating unit (I) in the presence of an acid. It has an acid dissociable organic group having a carbon number of 20 or less (hereinafter referred to as “acid dissociable organic group (i)”) that dissociates to form an acidic functional group. Preferred acid dissociable organic groups (i) include, for example, methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, i-
Propoxycarbonyl group, n-butoxycarbonyl group,
2-methylpropoxycarbonyl group, 1-methylpropoxycarbonyl group, t-butoxycarbonyl group, n-pentyloxycarbonyl group, n-hexyloxycarbonyl group, n-heptyloxycarbonyl group, n-octyloxycarbonyl group, n- (Cyclo) such as decyloxycarbonyl group, cyclopentyloxycarbonyl group, cyclohexyloxycarbonyl group, 4-t-butylcyclohexyloxycarbonyl group, cycloheptyloxycarbonyl group, cyclooctyloxycarbonyl group, etc.
Alkoxycarbonyl group; phenoxycarbonyl group, 4
Aryloxycarbonyl groups such as -t-butylphenoxycarbonyl group and 1-naphthyloxycarbonyl group; benzyloxycarbonyl group, 4-t-butylbenzyloxycarbonyl group, phenethyloxycarbonyl group, 4-
an aralkyloxycarbonyl group such as a t-butylphenethyloxycarbonyl group;

1-methoxyethoxycarbonyl group, 1-
Ethoxyethoxycarbonyl group, 1-n-propoxyethoxycarbonyl group, 1-i-propoxyethoxycarbonyl group, 1-n-butoxyethoxycarbonyl group, 1
-(2'-methylpropoxy) ethoxycarbonyl group,
1- (1′-methylpropoxy) ethoxycarbonyl group, 1-t-butoxyethoxycarbonyl group, 1-cyclohexyloxyethoxycarbonyl group, 1- (4′-
1- (cyclo) alkyloxyethoxycarbonyl group such as t-butylcyclohexyloxy) ethoxycarbonyl group; 1-phenoxyethoxycarbonyl group;
1-aryloxyethoxycarbonyl groups such as (4′-t-butylphenoxy) ethoxycarbonyl group and 1- (1′-naphthyloxy) ethoxycarbonyl group; 1-benzyloxyethoxycarbonyl group, 1- (4′-t −
Butylbenzyloxy) ethoxycarbonyl group, 1-phenethyloxyethoxycarbonyl group, 1- (4′-t
1-aralkyloxyethoxycarbonyl group such as -butylphenethyloxy) ethoxycarbonyl group; methoxycarbonylmethoxycarbonyl group, ethoxycarbonylmethoxycarbonyl group, n-propoxycarbonylmethoxycarbonyl group, i-propoxycarbonylmethoxycarbonyl group, n-butoxycarbonyl Methoxycarbonyl group, 2-methylpropoxycarbonylmethoxycarbonyl group, 1-methylpropoxycarbonylmethoxycarbonyl group, t-butoxycarbonylmethoxycarbonyl group, cyclohexyloxycarbonylmethoxycarbonyl group, 4-t-butylcyclohexyloxycarbonylmethoxycarbonyl group, etc. (Cyclo) alkoxycarbonylmethoxycarbonyl group;

Methoxycarbonylmethyl, ethoxycarbonylmethyl, n-propoxycarbonylmethyl, i-propoxycarbonylmethyl, n-butoxycarbonylmethyl, 2-methylpropoxycarbonylmethyl, 1-methylpropoxycarbonylmethyl,
(cyclo) alkoxycarbonylmethyl groups such as t-butoxycarbonylmethyl group, cyclohexyloxycarbonylmethyl group, 4-t-butylcyclohexyloxycarbonylmethyl group; phenoxycarbonylmethyl group,
Aryloxycarbonylmethyl groups such as -t-butylphenoxycarbonylmethyl group, 1-naphthyloxycarbonylmethyl group; benzyloxycarbonylmethyl group;
Aralkyloxycarbonylmethyl groups such as -t-butylbenzyloxycarbonylmethyl group, phenethyloxycarbonylmethyl group, 4-t-butylphenethyloxycarbonylmethyl group; 2-methoxycarbonylethyl group, 2-ethoxycarbonylethyl group, 2- n-propoxycarbonylethyl group, 2-i-propoxycarbonylethyl group, 2-n-butoxycarbonylethyl group, 2
-(2'-methylpropoxy) carbonylethyl group, 2
-(1′-methylpropoxy) carbonylethyl group, 2
A 2-tert-butoxycarbonylethyl group, a 2-cyclohexyloxycarbonylethyl group, a 2- (4'-tert-butylcyclohexyloxycarbonyl) ethyl group, or the like;
(Cyclo) alkoxycarbonylethyl group; 2-aryloxycarbonylethyl such as 2-phenoxycarbonylethyl group, 2- (4'-t-butylphenoxycarbonyl) ethyl group, 2- (1'-naphthyloxycarbonyl) ethyl group Groups; 2-benzyloxycarbonylethyl group, 2- (4'-t-butylbenzyloxycarbonyl) ethyl group, 2-phenethyloxycarbonylethyl group, 2- (4'-t-butylphenethyloxycarbonyl) ethyl group, and the like A 2-aralkyloxycarbonylethyl group, a tetrahydrofuranyloxycarbonyl group, a tetrahydropyranyloxycarbonyl group, and the like.

Among these acid dissociable organic groups (i), the group -COOR '(where R' represents a (cyclo) alkyl group having 1 to 19 carbon atoms). ] Or a group -COOCH ₂ COOR '' (however, R ''
Represents a (cyclo) alkoxycarbonylmethyl group having 1 to 17 carbon atoms. And particularly preferably a 1-methylpropoxycarbonyl group, a t-butoxycarbonyl group, and a t-butoxycarbonylmethoxycarbonyl group.

Examples of the alkyl group having 1 to 4 carbon atoms of X and Y in the repeating unit (I) include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-propyl group.
-Butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like. Further, n in the repeating unit (I) is preferably 0 or 1, and particularly preferably 1.

As the monomer giving such a repeating unit (I), for example, a norbornene derivative represented by the following general formula (3) (hereinafter referred to as “norbornene derivative (3)”)
That. ).

[0017]

Embedded image [In the general formula (3), A, B, X, Y and n represent A, B, X, and A in the general formulas (1) and (2), respectively.
It is synonymous with Y and n. ]

Specific examples of the compound in which n in the repeating unit (I) is 0 among the norbornene derivatives (3) include:
5-methoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-ethoxycarbonylbicyclo [2.
2.1] Hept-2-ene, 5-n-propoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-i
-Propoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-n-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 5- (2'-methylpropoxy) carbonylbicyclo [2 2.2.1] Hept-2-ene, 5- (1′-methylpropoxy) carbonylbicyclo [2.2.1] hept-2-ene, 5-t-
Butoxycarbonylbicyclo [2.2.1] hept-2
-Ene, 5-cyclohexyloxycarbonylbicyclo [2.2.1] hept-2-ene, 5- (4'-t-butylcyclohexyloxy) carbonylbicyclo [2.
2.1] Hept-2-ene, 5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene, 5- (1 ′
-Ethoxyethoxy) carbonylbicyclo [2.2.
1] Hept-2-ene, 5- (1′-cyclohexyloxyethoxy) carbonylbicyclo [2.2.1] hept-2-ene, 5-t-butoxycarbonylmethoxycarbonylbicyclo [2.2.1] hept -2-ene, 5
-Tetrahydrofuranyloxycarbonylbicyclo [2.2.1] hept-2-ene, 5-tetrahydropyranyloxycarbonylbicyclo [2.2.1] hept-2-ene,

5-methyl-5-methoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5
-Ethoxycarbonylbicyclo [2.2.1] hept-
2-ene, 5-methyl-5-n-propoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5-i-propoxycarbonylbicyclo [2.2.
1] hept-2-ene, 5-methyl-5-n-butoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5- (2'-methylpropoxy) carbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5- (1'-methylpropoxy) carbonylbicyclo [2.2.1] Hept-2-ene, 5-methyl-5
t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5-cyclohexyloxycarbonylbicyclo [2.2.1] hept-2-ene, 5
-Methyl-5- (4'-t-butylcyclohexyloxy) carbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5-phenoxycarbonylbicyclo [2.2.1] hept-2- Ene, 5-methyl-5
(1′-ethoxyethoxy) carbonylbicyclo [2.
2.1] Hept-2-ene, 5-methyl-5- (1′-
Cyclohexyloxyethoxy) carbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5-t
-Butoxycarbonylmethoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-methyl-5-tetrahydrofuranyloxycarbonylbicyclo [2.
2.1] Hept-2-ene, 5-methyl-5-tetrahydropyranyloxycarbonylbicyclo [2.2.1]
Hept-2-ene,

5,6-di (methoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (ethoxycarbonyl) bicyclo [2.2.1] hept-2-
Ene, 5,6-di (n-propoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (i-
Propoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (n-butoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (2 ′ -Methylpropoxycarbonyl) bicyclo [2.
2.1] Hept-2-ene, 5,6-di (1′-methylpropoxycarbonyl) bicyclo [2.2.1] Hept-2-ene, 5,6-di (t-butoxycarbonyl) bicyclo [ 2.2.1] Hept-2-ene, 5,6-di (cyclohexyloxycarbonyl) bicyclo [2.
2.1] Hept-2-ene, 5,6-di (4′-t-butylcyclohexyloxycarbonyl) bicyclo [2.
2.1] hept-2-ene, 5,6-di (phenoxycarbonyl) bicyclo [2.2.1] hept-2-ene,
5,6-di (1′-ethoxyethoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (1′-cyclohexyloxyethoxycarbonyl) bicyclo [2.2.1] hept -2-ene, 5,6-di (t-butoxycarbonylmethoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (tetrahydrofuranyloxycarbonyl) bicyclo [2.
2.1] hept-2-ene, 5,6-di (tetrahydropyranyloxycarbonyl) bicyclo [2.2.1] hept-2-ene and the like.

Specific examples of the compound in which n in the repeating unit (I) is 1 include 8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-
Ene, 8-ethoxycarbonyltetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-n-propoxycarbonyl tetracyclo [4.4.0.1 ^{2, 5.}
1 ^7,10 ] dodec-3-ene, 8-i-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-n-butoxycarbonyl tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene,
8- (2'-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8- (1′-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-t-butoxycarbonyltetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-cyclohexyl oxycarbonyl tetracyclo [4.4.0.1
^2,5 . 1 ^7,10] dodeca-3-ene, 8- (4'-t- butyl cyclohexyloxy) carbonyl tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene, 8
-Phenoxycarbonyltetracyclo [4.4.0.1
^2,5 . 1 ^7,10] dodeca-3-ene, 8- (1'-ethoxyethoxy) carbonyl tetracyclo [4.4.0.1
^2,5 . 1 ^7,10] dodeca-3-ene, 8- (1'-cyclohexyloxy) -carbonyl tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene, 8
-T-butoxycarbonylmethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-tetrahydrofuranyloxy carbonyl tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10] dodeca-3-ene, 8-tetrahydropyranyloxy carbonyl tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene,

8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-
Ene, 8-methyl-8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-methyl-8-n-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-methyl-8-i-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-methyl-8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8
-Methyl-8- (2'-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodeca
3-ene, 8-methyl-8- (1'-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1
^7,10 ] dodec-3-ene, 8-methyl-8-t-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1
^7,10 ] dodeca-3-ene, 8-methyl-8-cyclohexyloxycarbonyltetracyclo [4.4.0.1
^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-
(4′-t-butylcyclohexyloxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodeca
3-ene, 8-methyl-8-phenoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-
Ene, 8-methyl-8- (1'-ethoxyethoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ]
Dodeca-3-ene, 8-methyl-8- (1′-cyclohexyloxyethoxy) carbonyltetracyclo [4.
4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-methyl -8-t-butoxycarbonyl-methoxycarbonyltetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] Dodeca-3
-Ene, 8-methyl-8-tetrahydrofuranyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10
] Dodeca-3-ene, 8-methyl-8-tetrahydropyranyloxycarbonyltetracyclo [4.4.0.1
^2,5 . 1 ^7,10 ] dodec-3-ene,

8,9-di (methoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,9-di (ethoxycarbonyl) tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene,
8,9-di (n-propoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8,9-di (i-propoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8,9-di (n-butoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8,9-di (2′-methylpropoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-
Ene, 8,9-di (1′-methylpropoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,9-di (t-butoxycarbonyl)
Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodeca
3-ene, 8,9-di (cyclohexyloxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,9-di (4'-t-butylcyclohexyl butyloxycarbonyl) tetracyclo [4.4.0.
^12.5 . 1 ^7,10] dodeca-3-ene, 8,9-di (phenoxycarbonyl) tetracyclo [4.4.0.1
^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (1′-
Ethoxyethoxycarbonyl) tetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,9-di (1'-cyclohexyloxy-ethoxycarbonyl) tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] Dodeca-3
-Ene, 8,9-di (t-butoxycarbonylmethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1
^7,10 ] dodec-3-ene, 8,9-di (tetrahydrofuranyloxycarbonyl) tetracyclo [4.4.0.
^12.5 . 1 ^7,10] dodeca-3-ene, 8,9-di (tetrahydropyranyloxy carbonyl) tetracyclo [4.4.0.1 ^{2, 5.} [ ^1,7,10 ] dodec-3-ene and the like.

Among these norbornene derivatives (3), 5-t-butoxycarbonylbicyclo [2.2.
1] hept-2-ene, 5,6-di (t-butoxycarbonyl) bicyclo [2.2.1] hept-2-ene,
5,6-di (t-butoxycarbonylmethoxycarbonyl) bicyclo [2.2.1] hept-2-ene, 8-t
-Butoxycarbonyltetracyclo [4.4.0.1
^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-t
-Butoxycarbonyltetracyclo [4.4.0.1
^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-t
-Butoxycarbonylmethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . [ ^17,10 ] dodec-3-ene and the like are preferred. In the copolymer (1) and the copolymer (2), the repeating unit (I) may be used alone or in combination of two or more.

The repeating unit (II) in the general formulas (1) and (2) is a unit derived from maleic anhydride. Maleic anhydride has good copolymerizability with the norbornene derivative (3). By copolymerizing with the norbornene derivative (3), the molecular weight of the obtained copolymer (1) and copolymer (2) is reduced. It can be as large as desired. Next, as a monomer giving the repeating unit (III-1) in the general formula (1), for example,
A (meth) acrylic acid derivative represented by the following general formula (4) (hereinafter, referred to as “(meth) acrylic acid derivative (4)”) can be given.

[0026]

Embedded image In [general formula (4), R ¹ and R ² are each of general formula (1) the same meaning as that of R ¹ and R ^2. ]

Specific examples of the (meth) acrylic acid derivative (4) include compounds represented by the following formulas (4-1) to (4-24).

[0028]

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[0029]

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[0030]

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[0031]

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[0032]

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[0033]

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These (meth) acrylic acid derivatives (4)
Of these, compounds represented by the formula (4-2), the formula (4-4), the formula (4-5), the formula (4-8) or the formula (4-15) are preferable. In the copolymer (1), the repeating unit (III-1) may be present alone or in combination of two or more.

The monomer giving the repeating unit (III-2) in the general formula (2) includes, for example, a (meth) acrylic acid derivative represented by the following general formula (5)
It is referred to as “(meth) acrylic acid derivative (5)”. ).

[0036]

Embedded image In [general formula (5), R ¹ and R ³ are each of general formula (2) the same meanings as those of R ¹ and R ^3. ]

Specific examples of the (meth) acrylic acid derivative (5) include compounds represented by the following formulas (5-1) to (5-21).

[0038]

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[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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These (meth) acrylic acid derivatives (5)
Of the equations (5-2), (5-4), (5-5) or (5-1
Compounds represented by 4) are preferred. In the copolymer (2), the repeating unit (III-2) may be present alone or in combination of two or more.

Further, the copolymer (1) and the copolymer (2) have at least one kind of a repeating unit derived from another polymerizable unsaturated compound (hereinafter, referred to as “another repeating unit”). Can also. As another repeating unit, for example,
Norbornene (ie, bicyclo [2.2.1] hept-
2-ene), a repeating unit obtained by cleavage of a polymerizable carbon-carbon double bond of a norbornene derivative not containing an acid-dissociable organic group (hereinafter, referred to as “other norbornene derivative (α)”), The repeating unit obtained by cleaving the carbon-carbon double bond of a compound having a polymerizable carbon-carbon double bond other than the above (hereinafter, referred to as “other monomer (β)”) may be mentioned. it can.

Other norbornene derivatives (α) include:
For example, 5-methylbicyclo [2.2.1] hept-2
-Ene, 5-ethylbicyclo [2.2.1] hept-2
-Ene, 5-hydroxybicyclo [2.2.1] hept-2-ene, 5-hydroxymethylbicyclo [2.2.
1] hept-2-ene, bicyclo [2.2.1] hept-2-ene-5,6-dicarboxylic anhydride, bicyclo [2.2.1] hept-2-ene-5,6 (3H ) -Furanone, bicyclo [2.2.1] hept-2-ene-
5,6- (3,3-dimethyl) furanone, 2-carboxybicyclo [2.2.1] hept-2-en-2-ylacetic anhydride, tetracyclo [4.4.0.1 ^2,5 . 1
^7,10 ] dodec-3-ene, 8-methyltetracyclo
[4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8
-Ethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ]
Dodeca-3-ene, 8-hydroxytetracyclo [4.
4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-hydroxymethyl-tetracyclo [4.4.0.1 ^{2, 5.} 1
^7,10 ] dodeca-3-ene, 8-fluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8
-Fluoromethyltetracyclo [4.4.0.1 ^2,5 .
1 ^7,10 ] dodec-3-ene, 8-difluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-
Ene, 8-trifluoromethyltetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-pentafluoroethyl tetracyclo [4.4.0.1 ^{2, 5.} 1
^7,10 ] dodec-3-ene, 8,8-difluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,9-difluoro-tetracyclo [4.4.0.1
^2,5 . 1 ^7,10] dodeca-3-ene, 8,8-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^{2, 5.}
1 ^7,10] dodeca-3-ene, 8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10
] Dodec-3-ene, 8-methyl-8-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,8,9- trifluoro-tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene,
8,8,9-Tris (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8,8,9,9-tetrafluorotetracyclo [4.
4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,8,
9,9-Tetrakis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,

8,8-difluoro-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .
1 ^7,10] dodeca-3-ene, 8,9-difluoro -8,
9-bis (trifluoromethyl) tetracyclo [4.
4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,8,
9-trifluoro-9-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8,8,9-Trifluoro-9-trifluoromethoxytetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodeca
3-ene, 8,8,9-trifluoro-9-pentafluoropropoxytetracyclo [4.4.0.1 ^2,5 . 1
^7,10 ] dodec-3-ene, 8-fluoro-8-pentafluoroethyl-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodeca-3
-Ene, 8,9-difluoro-8-heptafluoroisopropyl-9-trifluoromethyltetracyclo [4.
4.0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8-chloro -8,9,9- trifluoro tetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10] dodeca-3-ene, 8,9-dichloro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 ] dodec-3-ene,
8- (2 ', 2', 2'-trifluorocarboethoxy) tetracyclo [4.4.0.1 ^2,5 . [ ^17,10 ] dodec-3-ene, 8-methyl-8- (2 ', 2', 2'-
(Trifluorocarboethoxy) tetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,

Dicyclopentadiene, tricyclo [5.
2.1.0 ^2,6 ] deca-8-ene, tricyclo [5.
2.1.0 ^2,6 ] deca-3-ene, tricyclo [4.
4.0.1 ^2,5 ] undec-3-ene, tricyclo [6.2.1.0 ^1,8 ] undec-9-ene, tricyclo [6.2.1.0 ^1,8 ] undec-4 -Ene, tetracyclo [4.4.0.1 ^2,5 . ^17,10 . 0 ^1,6 ] dodec-3-ene, 8-methyltetracyclo [4.4.0.1
^2,5 . ^17,10 . 0 ^1,6 ] dodeca-3-ene, 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . [ ^1,7,12 ] dodec-3-ene, 8-ethylidenetetracyclo [4.4.
0.1 ^2,5 . ^17,10 . 0 ^1,6 ] dodeca-3-ene, pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13] pentadeca-4-ene, pentacyclo [7.4.0.1
^2,5 . ^19,12 . 0 ^8,13] pentadeca-3-ene, or the like can be mentioned.

Further, other monomers (β) include, for example, norbornyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, tetracyclodecane (meth) acrylate Nyl, dicyclopentenyl (meth) acrylate, adamantyl (meth) acrylate, adamantyl methyl (meth) acrylate, 1-methyladamantyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate,
N-propyl (meth) acrylate, n-butyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) ) Cyclopropyl acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclohexenyl (meth) acrylate, 4-methoxycyclohexyl (meth) acrylate, 2-cyclopropyloxycarbonylethyl (meth) acrylate , 2-cyclopentyloxycarbonylethyl (meth) acrylate, (meth)
(Meth) acrylates such as 2-cyclohexyloxycarbonylethyl acrylate, 2-cyclohexenyloxycarbonylethyl (meth) acrylate, 2- (4'-methoxycyclohexyl) oxycarbonylethyl (meth) acrylate;

Methyl α-hydroxymethyl acrylate,
α-hydroxymethyl acrylates such as ethyl α-hydroxymethyl acrylate, n-propyl α-hydroxymethyl acrylate, and n-butyl α-hydroxymethyl acrylate; vinyl acetate, vinyl propionate,
Vinyl esters such as vinyl butyrate; unsaturated nitrile compounds such as (meth) acrylonitrile, α-chloroacrylonitrile, crotonitrile, maleinitrile, fumaronitrile, mesaconnitrile, citraconitrile, itaconitrile; and (meth) acrylamide, N, N −
Unsaturated amide compounds such as dimethyl (meth) acrylamide, crotonamide, maleamide, fumaramide, mesaconamide, citraconamide and itaconamide;
Other nitrogen-containing vinyl compounds such as N-vinyl-ε-caprolactam, N-vinylpyrrolidone, vinylpyridine, vinylimidazole; (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citracone Acids, unsaturated carboxylic acids (anhydrides) such as mesaconic acid; 2-carboxyethyl (meth) acrylate,
2-carboxypropyl (meth) acrylate, (meth)
3-carboxypropyl acrylate, 4-carboxybutyl (meth) acrylate, 4-carboxycyclohexyl (meth) acrylate, carboxytricyclodecanyl (meth) acrylate, carboxytetracyclodecanyl (meth) acrylate A carboxyl group-containing ester of an unsaturated carboxylic acid; a hydrogen atom in the carboxyl group of the unsaturated carboxylic acid or the carboxyl group-containing ester of the unsaturated carboxylic acid is converted to an acid dissociable organic group described below (hereinafter referred to as “acid dissociation”). Monofunctional monomer such as a compound substituted with a functional organic group (ii)

Methylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2,5-dimethyl-2,5-hexane Diol di (meth) acrylate, 1,8-octanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate,
1,4-bis (2-hydroxypropyl) benzenedi (meth) acrylate, 1,3-bis (2-hydroxypropyl) benzenedi (meth) acrylate, 1,2-
Adamantanediol di (meth) acrylate, 1,3
-Adamantanediol di (meth) acrylate, 1,
Examples thereof include polyfunctional monomers such as 4-adamantanediol di (meth) acrylate and tricyclodecanyl dimethylol di (meth) acrylate.

The acid dissociable organic group (ii) includes, for example,
Substituted methyl group, 1-substituted ethyl group, 1-branched alkyl group, silyl group, germyl group, alkoxycarbonyl group,
An acyl group or a cyclic acid dissociable group (provided that a compound in which a hydrogen atom of a carboxyl group in (meth) acrylic acid is substituted with the cyclic acid dissociable group is a (meth) acrylic acid derivative (4) or (meth) Excluding the case corresponding to the acrylic acid derivative (5)). Examples of the substituted methyl group include methoxymethyl group, methylthiomethyl group, ethoxymethyl group, ethylthiomethyl group, methoxyethoxymethyl group, benzyloxymethyl group, benzylthiomethyl group, phenacyl group, bromophenacyl group, methoxyphenacyl Group, methylthiophenacyl group, α-methylphenacyl group, cyclopropylmethyl group, benzyl group, diphenylmethyl group, triphenylmethyl group, bromobenzyl group, nitrobenzyl group, methoxybenzyl group, methylthiobenzyl group, ethoxybenzyl group , Ethylthiobenzyl group, piperonyl group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, n-propoxycarbonylmethyl group, isopropoxycarbonylmethyl group, n-butoxycarbonylmethyl group, t-butoxy Rubonirumechiru group, and the like can be mentioned. Examples of the 1-substituted ethyl group include a 1-methoxyethyl group, a 1-methylthioethyl group, a 1,1-dimethoxyethyl group, a 1-ethoxyethyl group, a 1-ethylthioethyl group, and a 1,1- Diethoxyethyl group, 1-phenoxyethyl group, 1-phenylthioethyl group, 1,1-diphenoxyethyl group, 1-benzyloxyethyl group, 1-benzylthioethyl group, 1-cyclopropylethyl group, 1-
Phenylethyl group, 1,1-diphenylethyl group, 1-
Methoxycarbonylethyl group, 1-ethoxycarbonylethyl group, 1-n-propoxycarbonylethyl group, 1
-Isopropoxycarbonylethyl group, 1-n-butoxycarbonylethyl group, 1-t-butoxycarbonylethyl group and the like.

Further, as the 1-branched alkyl group,
For example, isopropyl group, sec-butyl group, t-butyl group, 1,1-dimethylpropyl group, 1-methylbutyl group, 1,1-dimethylbutyl group and the like can be mentioned. Examples of the silyl group include a trimethylsilyl group, an ethyldimethylsilyl group, a methyldiethylsilyl group, a triethylsilyl group, an isopropyldimethylsilyl group, a methyldiisopropylsilyl group, a triisopropylsilyl group, a t-butyldimethylsilyl group, -T-butylsilyl group, tri-t-butylsilyl group, phenyldimethylsilyl group, methyldiphenylsilyl group,
And a triphenylsilyl group. Also,
Examples of the germyl group include trimethylgermyl group, ethyldimethylgermyl group, methyldiethylgermyl group, triethylgermyl group, isopropyldimethylgermyl group, methyldiisopropylgermyl group, triisopropylgermyl group, t- Butyldimethylgermyl group,
Examples thereof include a methyldi-t-butylgermyl group, a tri-t-butylgermyl group, a phenyldimethylgermyl group, a methyldiphenylgermyl group, and a triphenylgermyl group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, an isopropoxycarbonyl group, and a t-butoxycarbonyl group.

Examples of the acyl group include, for example, acetyl, propionyl, butyryl, heptanoyl, hexanoyl, valeryl, pivaloyl, isovaleryl, lauryloyl, myristoyl, palmitoyl, stearoyl, oxalyl. Group, malonyl group, succinyl group, glutaryl group, adipoyl group, piperoyl group, suberoyl group, azelaoil group, sebacoil group, acryloyl group, propioloyl group, methacryloyl group, crotonoyl group, oleoyl group, maleoyl group,
Fumaroyl group, mesaconoyl group, camphoroyl group, benzoyl group, phthaloyl group, isophthaloyl group, terephthaloyl group, naphthoyl group, toluoyl group, hydroatropoyl group, atropoyl group, cinnamoyl group, furoyl group, tenoyl group, nicotinoyl group, isonicotinoyl group , P-toluenesulfonyl group, mesyl group and the like. Further, examples of the cyclic acid dissociable group include a 3-oxocyclohexyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a tetrahydrothiopyranyl group, a tetrahydrothiofuranyl group, a 3-bromotetrahydropyranyl group, -Methoxytetrahydropyranyl group, 2-oxo-4-methyl-4-tetrahydropyranyl group, 4-methoxytetrahydrothiopyranyl group,
Examples thereof include a 3-tetrahydrothiophene-1,1-dioxide group.

In the copolymer (1) and the copolymer (2), the total content of the repeating units (I) and the repeating units derived from norbornene and other norbornene derivatives (α) is defined as the total content of all repeating units. On the other hand, it is usually 20 to 95 mol%, preferably 30 to 80 mol%, and more preferably 35 to 80 mol%, and the content of the repeating unit (II) is usually 5 to 5 ~ 85 mol%, preferably 10-50 mol%, more preferably 10-4 mol%
5 mol%, and the content of the repeating unit (III-1) or the repeating unit (III-2) is usually 5 relative to all the repeating units.
７５75 mol%, preferably 10-50 mol%, more preferably 10-45 mol%, and the content of the repeating unit derived from the other monomer (β) is usually 10 mol% or less, preferably 8 mol% or less,
More preferably, it is at most 5 mol%. In this case, the total content of the repeating unit (I) and the repeating unit derived from norbornene and another norbornene derivative (α) is 2%.
If it is less than 0 mol%, the dry etching resistance of the resist tends to decrease.
There is a tendency that the developability as a resist and the adhesiveness to a substrate are reduced. When the content of the repeating unit (II) is less than 5 mol%, the adhesiveness to the substrate as a resist tends to decrease, while when it exceeds 85 mol%, the dry etching resistance as the resist tends to decrease. There is.
When the content of the repeating unit (III-1) or the repeating unit (III-2) is less than 5 mol%, the developability of the resist tends to decrease. Resolution and heat resistance tend to decrease. Furthermore, the content of the repeating unit (I) relative to the total of the repeating unit (I) and the repeating units derived from norbornene and other norbornene derivatives (α) is usually 20%.
-100 mol%, preferably 40-100 mol%, more preferably 50-100 mol%. In this case, when the content of the repeating unit (I) is less than 20 mol%, the resolution as a resist tends to decrease.

The copolymer (1) and the copolymer (2)
For example, hydroperoxides of a norbornene derivative (3), maleic anhydride and a (meth) acrylic acid derivative (4) or a (meth) acrylic acid derivative (5), optionally together with another polymerizable unsaturated compound, It can be produced by using a radical polymerization initiator such as dialkyl peroxides, diacyl peroxides, and azo compounds and copolymerizing in a suitable solvent. Examples of the solvent used for the copolymerization include alkanes such as n-pentane, n-hexane, n-heptane, n-octane, n-nonane and n-decane; cyclohexane, cycloheptane, cyclooctane and decalin. , Alkanes such as benzene, toluene, xylene, ethylbenzene, cumene; halogenated hydrocarbons such as chlorobutane, bromohexanes, dichloroethanes, hexamethylene dibromide, chlorobenzene; acetic acid Ethyl, n-butyl acetate, i-butyl acetate,
Saturated carboxylic esters such as methyl propionate; ethers such as tetrahydrofuran, dimethoxyethane, and diethoxyethane; These solvents can be used alone or in combination of two or more. The reaction temperature in the copolymerization is usually 40 to 120 ° C, preferably 50 to 90 ° C,
The reaction time is generally 1 to 48 hours, preferably 1 to 24 hours.
Time.

The weight average molecular weight (hereinafter, referred to as “Mw”) of the copolymer (1) and the copolymer (2) in terms of polystyrene by gel permeation chromatography (GPC) is usually from 3,000 to 300, 000, preferably 4,000 to 200,000, more preferably 5,000 to 100,000. In this case, when the Mw of the copolymer (1) and the copolymer (2) is less than 3,000, the heat resistance as a resist tends to decrease,
On the other hand, if it exceeds 300,000, the developability as a resist tends to decrease. It is preferable that the copolymer (1) and the copolymer (2) have less impurities such as halogens and metals, thereby further improving the sensitivity, resolution, process stability, pattern shape, and the like as a resist. Can be. Copolymer (1) and copolymer (2)
Examples of the purification method include chemical purification methods such as water washing and liquid-liquid extraction, and combinations of these chemical purification methods with physical purification methods such as ultrafiltration and centrifugation. In the present invention, the copolymer (1) and the copolymer (2) can be used alone or in admixture of two or more, and the copolymer (1) and the copolymer (2) can be used.
And can be used in combination.

Component (B) Next, the component (B) in the present invention is a radiation-sensitive acid generator that generates an acid upon exposure (hereinafter referred to as “acid generator (B)”).
That. ). The acid generator (B) dissociates the acid-dissociable organic groups present in the resin (A) by the action of the acid generated by the exposure, and as a result, the exposed portion of the resist film becomes easily soluble in an alkali developer, It has the function of forming a positive resist pattern. Examples of such an acid generator (B) include onium salts, halogen-containing compounds, diazoketone compounds, sulfone compounds,
Sulfonic acid compounds and the like can be mentioned. Examples of these acid generators (B) include the following.

Onium salt: Examples of the onium salt include an iodonium salt, a sulfonium salt (including a tetrahydrothiophenium salt), a phosphonium salt, a diazonium salt, a pyridinium salt and the like. Specific examples of preferred onium salts include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium pyrene sulfonate, diphenyliodonium n-dodecylbenzenesulfonate, diphenyliodonium hexafluoroantimonate, bis (4-t -Butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium n
-Dodecylbenzenesulfonate, bis (4-t-butylphenyl) iodonium hexafluoroantimonate, bis (4-t-butylphenyl) iodonium naphthalene sulfonate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate , Triphenylsulfonium hexafluoroantimonate, triphenylsulfonium naphthalene sulfonate, triphenylsulfonium 10-camphorsulfonate, 4-hydroxyphenyl phenyl methylsulfonium p
-Toluenesulfonate, cyclohexyl-2-oxocyclohexylmethylsulfonium trifluoromethanesulfonate, dicyclohexyl-2-oxocyclohexylsulfoniumtrifluoromethanesulfonate, 2-oxocyclohexyldimethylsulfoniumtrifluoromethanesulfonate, 4-hydroxyphenylbenzylmethylsulfonium p-toluene Sulfonate, 1-naphthyldimethylsulfonium trifluoromethanesulfonate, 1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4-cyano-
1-naphthyldimethylsulfonium trifluoromethanesulfonate, 4-nitro-1-naphthyldimethylsulfonium trifluoromethanesulfonate, 4-methyl-1-naphthyldimethylsulfonium trifluoromethanesulfonate, 4-cyano-1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4- Nitro-1-naphthyl diethylsulfonium trifluoromethanesulfonate, 4-methyl-1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4-hydroxy-1-naphthyldimethylsulfonium trifluoromethanesulfonate,

4-hydroxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,
-Methoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-ethoxy-1-
Naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-n-butoxy-1-naphthyltetrahydrothiophenium nonafluoro-n-butanesulfonate, 4-methoxymethoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-ethoxymethoxy -1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-
(1′-methoxyethoxy) -1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4
-(2'-methoxyethoxy) -1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,
4-methoxycarbonyloxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,
4-ethoxycarbonyloxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,
4-n-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-i-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-n-butoxycarbonyloxy-1-
Naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-t-butoxycarbonyloxy-
1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4- (2'-tetrahydrofuranyloxy) -1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4- (2'-tetrahydropyranyloxy) -1-naphthyltetrahydrothio Phenium trifluoromethanesulfonate, 4-benzyloxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 1- (1′-naphthyl acetomethyl) tetrahydrothiophenium trifluoromethanesulfonate and the like can be mentioned.

Halogen-containing compound: Examples of the halogen-containing compound include a haloalkyl group-containing hydrocarbon compound and a haloalkyl group-containing heterocyclic compound. Specific examples of preferred halogen-containing compounds include phenylbis (trichloromethyl) -s-triazine and 4-methoxyphenylbis (trichloromethyl)-
(Trichloromethyl) -s- such as s-triazine and 1-naphthylbis (trichloromethyl) -s-triazine
Examples thereof include a triazine derivative and 1,1-bis (4′-chlorophenyl) -2,2,2-trichloroethane. Diazoketone compound: Examples of the diazoketone compound include a 1,3-diketo-2-diazo compound, a diazobenzoquinone compound, and a diazonaphthoquinone compound. Specific examples of preferred diazoketones include 1,2-naphthoquinonediazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-5-sulfonyl chloride, and 1,2-naphtho of 2,3,4,4'-tetrahydroxybenzophenone. Quinonediazide-4-sulfonic acid ester or 1,2-naphthoquinonediazide-
5-sulfonic acid ester, 1,1,1-tris (4′-
Examples thereof include 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester of (hydroxyphenyl) ethane.

Sulfone compound: Examples of the sulfone compound include β-ketosulfone, β-sulfonylsulfone, and α-diazo compounds of these compounds. Specific examples of preferred sulfone compounds include 4-trisphenacylsulfone, mesitylphenacylsulfone, bis (phenylsulfonyl) methane, and the like. Sulfonic acid compound: Examples of the sulfonic acid compound include alkylsulfonic acid esters, alkylsulfonic acid imides, haloalkylsulfonic acid esters, arylsulfonic acid esters, and iminosulfonates. Specific examples of preferred sulfonic acid compounds include benzoin tosylate, pyrogallol tris (trifluoromethanesulfonate), nitrobenzyl-
9,10-diethoxyanthracene-2-sulfonate, trifluoromethanesulfonylbicyclo [2.2.
1] hept-5-ene-2,3-dicarbodiimide, N
-Hydroxysuccinimide trifluoromethanesulfonate and 1,8-naphthalenedicarboxylic acid imide trifluoromethanesulfonate.

Among these acid generators (B), diphenyliodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n -Butanesulfonate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, cyclohexyl-2-oxocyclohexylmethylsulfonium trifluoromethanesulfonate, dicyclohexyl-2-oxocyclohexylsulfonium trifluoromethanesulfonate, 2-oxocyclohexyl Dimethylsulfonium trifluoromethanesulfonate, 4-hydroxy-1-
Naphthyldimethylsulfonium trifluoromethanesulfonate, 4-hydroxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 1-
(1′-naphthyl acetomethyl) tetrahydrothiophenium trifluoromethanesulfonate, trifluoromethanesulfonylbicyclo [2.2.1] hept-5-
En-2,3-dicarbodiimide, N-hydroxysuccinimide trifluoromethanesulfonate, 1,8-naphthalenedicarboxylic acid imide trifluoromethanesulfonate and the like are preferable.

In the present invention, the acid generator (B) can be used alone or in combination of two or more. The amount of the acid generator (B) used is usually 0.1 to 10 parts by weight, preferably 0.5 part by weight, based on 100 parts by weight of the resin (A) from the viewpoint of securing the sensitivity and developability as a resist.
７7 parts by weight. In this case, if the amount of the acid generator (B) used is less than 0.1 part by weight, sensitivity and developability tend to decrease, while if it exceeds 10 parts by weight, transparency to radiation decreases, and Tends to be difficult to obtain.

Various Additives The radiation-sensitive resin composition of the present invention controls the diffusion phenomenon of the acid generated from the acid generator (B) in the resist film upon exposure, and suppresses undesired chemical reactions in the unexposed area. It is preferable to add an acid diffusion controlling agent having an action of acting. By blending such an acid diffusion controller, the storage stability of the obtained radiation-sensitive resin composition is further improved, and the resolution as a resist is further improved, and the withdrawal time from exposure to development processing is increased. (P
Variations in the line width of the resist pattern due to variations in ED) can be suppressed, and a composition having extremely excellent process stability can be obtained. As the acid diffusion controller, a nitrogen-containing organic compound whose basicity is not changed by exposure or heat treatment during a resist pattern forming step is preferable. As such a nitrogen-containing organic compound, for example, the following general formula (6)

[0066]

Embedded image [In the general formula (6), R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group,
It represents a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group. ]

(Hereinafter, referred to as "nitrogen-containing compound (i)"), a compound having two nitrogen atoms in the same molecule (hereinafter, referred to as "nitrogen-containing compound (ii)"),
Examples thereof include polymers having three or more nitrogen atoms (hereinafter, referred to as “nitrogen-containing compound (iii)”), amide group-containing compounds, urea compounds, and nitrogen-containing heterocyclic compounds.

Examples of the nitrogen-containing compound (i) include, for example, n
Mono (cyclo) alkylamines such as -hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, cyclohexylamine;
Di-n-butylamine, di-n-pentylamine, di-
n-hexylamine, di-n-heptylamine, di-n
Di (cyclo) alkylamines such as -octylamine, di-n-nonylamine, di-n-decylamine, cyclohexylmethylamine and dicyclohexylamine; triethylamine, tri-n-propylamine, tri-n-
Butylamine, tri-n-pentylamine, tri-n-
Hexylamine, tri-n-heptylamine, tri-n
-Octylamine, tri-n-nonylamine, tri-n
-Tri (cyclo) alkylamines such as decylamine, cyclohexyldimethylamine, dicyclohexylmethylamine and tricyclohexylamine; aniline, N-
Examples thereof include aromatic amines such as methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, and naphthylamine.

Examples of the nitrogen-containing compound (ii) include ethylenediamine, N, N, N ', N'-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane,
4,4'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4'-aminophenyl) propane, 2- (3'-aminophenyl) -2- (4′-aminophenyl) propane, 2- (4′-aminophenyl)
-2- (3'-hydroxyphenyl) propane, 2-
(4′-aminophenyl) -2- (4′-hydroxyphenyl) propane, 1,4-bis [1 ′-(4 ″ -aminophenyl) -1′-methylethyl] benzene, 1,3
-Bis [1 '-(4 "-aminophenyl) -1'-methylethyl] benzene and the like.

Examples of the nitrogen-containing compound (iii) include polymers of polyethyleneimine, polyallylamine, 2-dimethylaminoethylacrylamide and the like. Examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, and N-methylpyrrolidone. Can be mentioned. As the urea compound,
For example, urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n-
Butylthiourea and the like can be mentioned. Examples of the nitrogen-containing heterocyclic compound include, for example, imidazole, benzimidazole, 4-methylimidazole, 4-methyl-
Imidazoles such as 2-phenylimidazole; pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine, Pyridines such as nicotine, nicotinic acid, nicotinamide, quinoline, 4-hydroxyquinoline, 8-oxyquinoline, acridine; piperazine, 1-
In addition to piperazines such as (2′-hydroxyethyl) piperazine, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, morpholine,
4-methylmorpholine, 1,4-dimethylpiperazine,
1,4-diazabicyclo [2.2.2] octane and the like can be mentioned.

Of these nitrogen-containing organic compounds, a nitrogen-containing compound (i) and a nitrogen-containing heterocyclic compound are preferable.
Among the nitrogen-containing compounds (i), tri (cyclo) alkylamines are particularly preferable, and among the nitrogen-containing heterocyclic compounds, pyridines and piperazines are particularly preferable. The acid diffusion controllers can be used alone or in combination of two or more. The compounding amount of the acid diffusion controller is as follows:
The amount is usually 15 parts by weight or less, preferably 10 parts by weight or less, more preferably 5 parts by weight or less based on 100 parts by weight. In this case, if the amount of the acid diffusion controller exceeds 15 parts by weight, the sensitivity as a resist and the developability of an exposed portion tend to decrease. In addition, the compounding amount of the acid diffusion control agent is 0.1.
If it is less than 001 parts by weight, depending on the process conditions,
There is a possibility that the pattern shape and dimensional fidelity as a resist may be reduced.

The radiation-sensitive resin composition of the present invention further comprises an alicyclic additive having an acid-dissociable organic group, which has an effect of further improving dry etching resistance, pattern shape, adhesion to a substrate, and the like. Can be blended. Such alicyclic additives include, for example, t-butyl 1-adamantanecarboxylate and t-butyl 3-adamantanecarboxylate.
Butyl, 1,3-adamantane dicarboxylic acid di-t-butyl, 1-adamantane acetate t-butyl, 3-adamantane acetate t-butyl, 1,3-adamantane diacetate di-
Adamantane derivatives such as t-butyl; t-butyl deoxycholate, t-butoxycarbonylmethyl deoxycholate, 2-ethoxyethyl deoxycholate, 2-cyclohexyloxyethyl deoxycholate, 3-oxocyclohexyl deoxycholate, Deoxycholates such as tetrahydropyranyl deoxycholate and mevalonolactone deoxycholate; t-butyl lithocholic acid, t-butoxycarbonylmethyl lithocholic acid, 2-ethoxyethyl lithocholic acid, 2-cyclohexyloxyethyl lithocholic acid And lithocholic acid esters such as 3-oxocyclohexyl lithocholic acid, tetrahydropyranyl lithocholic acid, and mevalonolactone lithocholic acid. These alicyclic additives can be used alone or in combination of two or more. The amount of the alicyclic additive is usually 50 parts by weight or less based on 100 parts by weight of the resin (A).
Preferably it is 30 parts by weight or less. In this case, if the amount of the alicyclic additive exceeds 50 parts by weight, the heat resistance of the resist tends to decrease.

The radiation-sensitive resin composition of the present invention may contain a surfactant having an effect of improving coating properties, developability and the like. Examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octyl phenyl ether, polyoxyethylene n-nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene In addition to nonionic surfactants such as glycol distearate, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.) and Polyflow No. No. 75, the same No. 95
(Manufactured by Kyoeisha Chemical Co., Ltd.), F-top EF301, E-top
F303, EF352 (Tochem Products Co., Ltd.)
), Megafax F171, F173 (manufactured by Dainippon Ink and Chemicals, Inc.), Florado FC430, F
C431 (manufactured by Sumitomo 3M Limited), Asahi Guard A
G710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, S
C-105, SC-106 (manufactured by Asahi Glass Co., Ltd.) and the like. These surfactants can be used alone or in combination of two or more. The compounding amount of the surfactant is a total of 1 for the resin (A) and the acid generator (B).
It is usually 2 parts by weight or less based on 00 parts by weight. Further, as additives other than the above, an antihalation agent,
Adhesion aids, storage stabilizers, defoamers and the like can be mentioned.

Preparation of Composition Solution The radiation-sensitive resin composition of the present invention is usually used such that the total solid content is usually 5 to 50% by weight, preferably 10 to 25% by weight. After dissolving in a solvent, the composition is prepared as a composition solution by filtering through, for example, a filter having a pore size of about 0.2 μm. Examples of the solvent used for preparing the composition solution include 2-
Butanone, 2-pentanone, 3-methyl-2-butanone, 2-hexanone, 4-methyl-2-pentanone,
Linear ketones such as -methyl-2-pentanone, 3,3-dimethyl-2-butanone, 2-heptanone and 2-octanone; cyclopentanone, 3-methylcyclopentanone, cyclohexanone, 2-methylcyclohexanone,
Cyclic ketones such as 2,6-dimethylcyclohexanone and isophorone; propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-i-
Propyl ether acetate, propylene glycol mono-n-butyl ether acetate, propylene glycol mono-i-butyl ether acetate, propylene glycol mono-sec-butyl ether acetate,
Propylene glycol monoalkyl ether acetates such as propylene glycol mono-t-butyl ether acetate; methyl 2-hydroxypropionate;
Ethyl hydroxypropionate, n-propyl 2-hydroxypropionate, i- 2-hydroxypropionate
Propyl, n-butyl 2-hydroxypropionate, 2
Alkyl 2-hydroxypropionates such as i-butyl hydroxypropionate, sec-butyl 2-hydroxypropionate and t-butyl 2-hydroxypropionate; methyl 3-methoxypropionate, ethyl 3-methoxypropionate; -In addition to alkyl 3-alkoxypropionates such as methyl ethoxypropionate and ethyl 3-ethoxypropionate,

N-propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclohexanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether,
Ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether Acetate, ethylene glycol mono-n-propyl ether acetate, propylene glycol monomethyl ether,
Propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, toluene, xylene, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-
Methyl hydroxy-3-methylbutyrate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, ethyl acetate, N-propyl acetate, n-butyl acetate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate, N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, benzyl ethyl ether, -N-hexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, caproic acid, caprylic acid,
Examples thereof include 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, and propylene carbonate.

These solvents can be used alone or in combination of two or more. Among them, linear ketones, cyclic ketones, propylene glycol monoalkyl ether acetates, 2-hydroxypropione Alkyl acids and alkyl 3-alkoxypropionates are preferred.

Method for Forming Resist Pattern The radiation-sensitive resin composition of the present invention is particularly useful as a chemically amplified positive resist. In the chemically amplified positive resist, an acid dissociable organic group in the resin (A) is dissociated by the action of an acid generated from the acid generator (B) upon exposure, thereby producing, for example, a carboxyl group. ,
The solubility of the exposed portion of the resist in an alkali developing solution is increased, and the exposed portion is dissolved and removed by the alkali developing solution to obtain a positive resist pattern. When forming a resist pattern from the radiation-sensitive resin composition of the present invention, the composition solution, by a suitable application means such as spin coating, casting coating, roll coating, for example, silicon wafer, coated with aluminum A resist film is formed by applying the resist film on a substrate such as a wafer that has been subjected to a heat treatment (hereinafter, referred to as “PB”) in some cases, and then the resist film is formed so as to form a predetermined resist pattern. Expose. The radiation used at this time is preferably an ArF excimer laser (wavelength 193 nm) or a KrF excimer laser (wavelength 248 nm). In the present invention, a heat treatment after exposure (hereinafter referred to as “P
EB ". ) Is preferred. By this PEB, the dissociation reaction of the acid dissociable organic group in the resin (A) proceeds smoothly. The heating conditions for PEB vary depending on the composition of the radiation-sensitive resin composition, but are usually 30 to 200.
° C, preferably 50 to 170 ° C.

In the present invention, in order to maximize the potential of the radiation-sensitive resin composition, for example,
As disclosed in Japanese Patent No. 12452 or the like, an organic or inorganic antireflection film can be formed on a substrate to be used, and the influence of basic impurities and the like contained in an environmental atmosphere can be reduced. To prevent this, see, for example, JP-A-5-18
As disclosed in Japanese Patent No. 8598 and the like, a protective film can be provided on a resist film, or these techniques can be used in combination. Next, a predetermined resist pattern is formed by developing the exposed resist film. Examples of the developer used for development include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, and di-n-propylamine. , Triethylamine,
Methyl diethylamine, ethyl dimethylamine, triethanolamine, tetramethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4. An alkaline aqueous solution in which at least one alkaline compound such as 3.0] -5-nonene is dissolved. The concentration of the alkaline aqueous solution is usually
10% by weight or less. In this case, if the concentration of the alkaline aqueous solution exceeds 10% by weight, unexposed portions may be dissolved in the developer, which is not preferable.

Further, for example, an organic solvent can be added to the developer comprising the alkaline aqueous solution. Examples of the organic solvent include acetone, methyl ethyl ketone, methyl i-butyl ketone, cyclopentanone, cyclohexanone, 3-methylcyclopentanone, 2,6
Ketones such as dimethylcyclohexanone; methyl alcohol, ethyl alcohol, n-propyl alcohol,
i-propyl alcohol, n-butyl alcohol, t-
Alcohols such as butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, and 1,4-hexanedimethylol; tetrahydrofuran;
Ethers such as dioxane; esters such as ethyl acetate, n-butyl acetate and i-amyl acetate; aromatic hydrocarbons such as toluene and xylene; phenol, acetonylacetone, and dimethylformamide. These organic solvents can be used alone or in combination of two or more. The amount of the organic solvent used is preferably 100% by volume or less based on the alkaline aqueous solution.
In this case, if the amount of the organic solvent used exceeds 100% by volume, the developability may be reduced and the undeveloped portion of the exposed portion may be increased. In addition, an appropriate amount of a surfactant or the like can be added to a developer composed of an alkaline aqueous solution. In addition,
After development with a developer composed of an alkaline aqueous solution, it is generally washed with water and dried.

[0080]

Embodiments of the present invention will be described below more specifically with reference to examples. However, the present invention is not limited to these embodiments. Here, parts and% are based on weight unless otherwise specified.
Each measurement and evaluation in Examples and Comparative Examples was performed in the following manner. Mw: Tosoh Corporation GPC column (G2000HXL 2
Gel permeation chromatography (GPC) using monodisperse polystyrene as a standard under the analytical conditions of flow rate 1.0 ml / min, elution solvent tetrahydrofuran, column temperature 40 ° C. It was measured. Storage stability: A 1 μm-thick resist film formed by applying the composition solution on a silicone wafer by spin coating and performing PB on a hot plate maintained at 140 ° C. for 90 seconds to form 2.38% tetramethyl After developing with an aqueous solution of ammonium hydroxide at 25 ° C. for 1 minute, washing with water and drying, the film thickness was measured. This film thickness is defined as an initial film thickness. In addition, the composition solution was held in a constant temperature bath at 50 ° C., and a resist film was formed, developed, washed with water, and dried using the composition solution every day, and the film thickness was measured. . This film thickness is defined as the film thickness after holding. At this time, the film thickness after holding is 50% of the initial film thickness.
The longest retention days exceeding 超 え る was determined as a measure of storage stability. The larger the number of retention days, the better the storage stability.

Radiation transmittance: A 1 μm-thick film formed by applying the composition solution onto quartz glass by spin coating and performing PB on a hot plate maintained at 90 ° C. for 60 seconds.
With respect to the resist coating of (1), the radiation transmittance was calculated from the absorbance at a wavelength of 193 nm and used as a measure of the transparency in the far ultraviolet region. Relative etching rate: A 0.5 μm-thick resist film formed by applying the composition solution on a silicon wafer by spin coating and drying is applied with an etching gas using a PMT dry etching apparatus (Pinnacle8000). and CF _4, the gas flow rate 75 sccm, pressure 2.5m
Dry etching was performed under the conditions of Torr and an output of 2500 W, the etching rate was measured, and the relative etching rate was evaluated based on the relative value to the etching rate of the film made of cresol novolak resin. The lower the etching rate, the better the dry etching resistance.

Sensitivity: As a substrate, a film having a thickness of 520 ° was formed on the surface.
A silicone wafer (ARC) having DeepUV30 (manufactured by Brewer Science) film formed thereon (Examples 1-3, Examples 5-9 and Comparative Example 1) or prepared so as to exhibit an antireflection effect at a wavelength of 193 nm on the surface. Silicon wafer with silicon oxynitride film (SiON)
Using (Example 4), the composition solution was applied on each substrate by spin coating, and PB was performed on a hot plate under the conditions shown in Table 2 to form a film having a thickness of 0.4 μm (Example 1). To 5, Examples 8 to 9 and Comparative Example 1) or a film thickness of 0.1.
The resist film having a thickness of 2 μm (Examples 6 and 7) was exposed through a mask pattern using an ArF excimer laser exposure device (Nikon Corporation, lens numerical aperture 0.55, exposure wavelength 193 nm). After that, PEB under the conditions shown in Table 2
, And a 2.38% aqueous solution of tetramethylammonium hydroxide (Examples 1 to 9) or 2.38 ×
The film was developed with a 1/50% aqueous solution of tetramethylammonium hydroxide (Comparative Example 1) at 25 ° C. for 1 minute, washed with water, and dried to form a positive resist pattern.
At this time, an exposure amount for forming a line-and-space pattern (1L1S) having a line width of 0.18 μm with a line width of 1: 1 was defined as an optimum exposure amount, and this optimum exposure amount was defined as a sensitivity. Resolution: The minimum dimension of the resist pattern resolved at the optimal exposure amount was defined as the resolution. Developability: The scum after development and the degree of development residue were evaluated using a scanning electron microscope. Pattern shape: lower side dimension L of a rectangular cross section of a line and space pattern (1L1S) having a line width of 0.20 μm
₁ and the upper and lower side dimensions L ₂ were measured by a scanning electron microscope. When the pattern satisfies 0.85 ≦ L ₂ / L ₁ ≦ 1 and the pattern shape did not have a tail, the pattern shape was “good”. The case where at least one of these conditions is not satisfied is regarded as the pattern shape being “defective”.

Synthesis Example 1 8-t-butoxycarbonyltetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10 ] dodeca-3-ene 104.1 g,
39.2 g of maleic anhydride, 39.6 g of the compound represented by the formula (4-4), 15 g of azobisisobutyronitrile,
A flask was charged with 274 g of n-butyl acetate and polymerized at 70 ° C. for 6 hours under a nitrogen atmosphere. After completion of the polymerization, the reaction solution was cooled to room temperature, poured into a large amount of i-propyl alcohol, and the precipitated resin was filtered, washed with a small amount of i-propyl alcohol, and then dried under vacuum to obtain an Mw of 1
7,000 white resins were obtained. This resin has a content of each repeating unit of (7-1), (7-2) and (7-3) shown in the following formula (7) of 40 mol%, 40 mol% and 2 mol%, respectively.
It was a copolymer consisting of 0 mol%. This resin is referred to as resin (A-1).

[0084]

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Synthesis Example 2 As starting materials for reaction, 77.7 g of 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 39.2 g of maleic anhydride, represented by the above formula (4-2) Compound 5
2.8 g, azobisisobutyronitrile 15 g, acetic acid n
A white resin having an Mw of 25,000 was obtained in the same manner as in Synthesis Example 1 except that 255 g of -butyl was used. In this resin, the content of each repeating unit of (8-1), (8-2) and (8-3) shown in the following formula (8) is 40 mol%, 40 mol% and 20 mol%, respectively. It was a copolymer. This resin is referred to as resin (A-2).

[0086]

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Synthesis Example 3 As reaction raw materials, 99.1 g of 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 36.8 g of maleic anhydride, represented by the above formula (4-5) Compound 53
g, 2,5-dimethyl-2,5-hexanediol diacrylate 12.7 g, azobisisobutyronitrile 1
A white resin having an Mw of 47,000 was obtained in the same manner as in Synthesis Example 1 except that 5 g and 300 g of n-butyl acetate were used. This resin is represented by the following formula (9) (9-1), (9-2),
It was a copolymer having a content of each repeating unit of (9-3) and (9-4) of 44 mol%, 37 mol%, 15 mol% and 4 mol%, respectively. This resin is referred to as resin (A-3).

[0088]

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Synthesis Example 4 As reaction raw materials, 77.7 g of 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 39.2 g of maleic anhydride, represented by the above formula (4-14) Compound 4
7.2 g, tricyclodecanyl dimethylol diacrylate 15.2 g, azobisisobutyronitrile 15 g,
A white resin having an Mw of 35,000 was obtained in the same manner as in Synthesis Example 1 except that 270 g of n-butyl acetate was used. This resin is represented by the following formula (10): (10-1), (10-2), (10-3)
And a copolymer in which the content of each repeating unit of (10-4) was 38 mol%, 38 mol%, 20 mol%, and 4 mol%, respectively. This resin is referred to as resin (A-4).

[0090]

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Synthesis Example 5 As reaction raw materials, 66 g of 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 41.7 g of maleic anhydride, a compound represented by the above formula (5-14) 35.
1 g, 8-hydroxymethyltetracyclo [4.4.
0.1 ^2,5 . 1 ^{7, 10]} dodeca-3-ene 16.2 g, dimethyl-2,2'-azobis isobutyrate 15 g, except for using acetic acid n- butyl 240 g, in the same manner as in Synthesis Example 1, Mw 18 2,000 white resins were obtained. This resin has a content of each repeating unit of (11-1), (11-2), (11-3) and (11-4) represented by the following formula (11) of 33 mol% and 42 mol%, respectively. , 15 mol% and 10 mol%. This resin is referred to as resin (A-5).

[0092]

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Synthesis Example 6 Bicyclo [2.2.1] hept-2-
5.2 g of ene-5,6-dicarboxylic anhydride, 5-t-
Butoxycarbonylbicyclo [2.2.1] hept-2
-Synthesis as in Synthesis Example 1 except that -ene 43 g, maleic anhydride 25 g, compound 28 g of the formula (4-7), dimethyl-2,2'-azobisisobutyrate 5 g, and tetrahydrofuran 100 g were used. And Mw is 12,000
0 white resin was obtained. This resin has a content of each repeating unit of (12-1), (12-2), (12-3) and (12-4) shown in the following formula (12) of 5 mol% and 36 mol%, respectively. , 41 mol%
And 18 mol%. This resin is referred to as resin (A-6).

[0094]

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Synthesis Example 7 Bicyclo [2.2.1] hept-2-
Ene-5,6 (3H) -furanone 7.0 g, 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-
The same procedures as in Synthesis Example 1 were carried out except that 44 g of ene, 27 g of maleic anhydride, 23 g of the compound represented by the above formula (4-7), 5 g of dimethyl-2,2'-azobisisobutyrate, and 100 g of tetrahydrofuran were used. And Mw is 10,000
Was obtained as a white resin. This resin has the following formula (13)
The content of each of the repeating units (13-1), (13-2), (13-3) and (13-4) is 7 mol%, 35 mol%, 42 mol% and 16 mol%, respectively. It was a polymer. This resin is referred to as resin (A-7).

[0096]

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Synthesis Example 8 Bicyclo [2.2.1] hept-2-
En-5,6- (3,3-dimethyl) furanone 8.0
g, 5-t-butoxycarbonylbicyclo [2.2.
1] 43 g of hept-2-ene, 26 g of maleic anhydride,
23 g of the compound represented by the formula (4-7), dimethyl-2,
M ′ was prepared in the same manner as in Synthesis Example 1 except that 5 g of 2′-azobisisobutyrate and 100 g of tetrahydrofuran were used.
A white resin having a w of 9,000 was obtained. This resin has a content of each repeating unit of (14-1), (14-2), (14-3) and (14-4) shown in the following formula (14) of 7 mol% and 35 mol%, respectively. , 42 mol% and 16 mol%. This resin is referred to as resin (A-8).

[0098]

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Synthesis Example 9 As reaction raw materials, 48 g of 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 24 g of maleic anhydride, 28 g of the compound represented by the above formula (4-8), A white resin having an Mw of 8,800 was obtained in the same manner as in Synthesis Example 1 except that 5 g of dimethyl-2,2′-azobisisobutyrate and 100 g of tetrahydrofuran were used. This resin is represented by the following formula (15), (15-1), (15-2) and (15-3)
Was a copolymer having a content of each repeating unit of 40 mol%, 40 mol% and 20 mol%, respectively. This resin is referred to as resin (A-9).

[0100]

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Synthesis Example 10 As reaction raw materials, 47 g of 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 19 g of maleic anhydride, 44 g of the compound represented by the above formula (4-7), A white resin having an Mw of 9,000 was obtained in the same manner as in Synthesis Example 1 except that 5 g of dimethyl-2,2′-azobisisobutyrate and 100 g of tetrahydrofuran were used. This resin is represented by the following formula (16), (16-1), (16-2) and (16-3)
Was a copolymer comprising 35 mol%, 35 mol%, and 30 mol% of each repeating unit. This resin is referred to as resin (A-10).

[0102]

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Synthesis Example 11 2-Carboxy-bicyclo [2.2.
1] 5.0 g of hept-2-en-2-ylacetic anhydride,
5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene 43 g, maleic anhydride 26 g, compound 23 g represented by the above formula (4-7), dimethyl-2,2′-
Azobisisobutyrate 5 g, tetrahydrofuran 10
A white resin having an Mw of 9,000 was obtained in the same manner as in Synthesis Example 1 except that 0 g was used. This resin has the following formula (1)
The content of each of the repeating units (17-1), (17-2), (17-3) and (17-4) shown in 7) is 7 mol%, 35 mol% and 4 mol%, respectively.
It was a copolymer consisting of 2 mol% and 16 mol%.
This resin is referred to as a resin (A-11).

[0104]

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[0105]

EXAMPLES Examples 1 to 15 and Comparative Example 1 Various composition solutions composed of the components shown in Table 1 were evaluated.
Value. Table 3 shows the evaluation results. Tree in Table 1
The components other than the fats (A-1) to (A-11) are as follows:
is there. Other resin a-1: t-butyl methacrylate / methyl methacrylate
/ Methacrylic acid copolymer (copolymer molar ratio = 40/40 /
20, Mw = 20,000)Acid generator (B) B-1: triphenylsulfonium trifluoromethane
Sulfonate B-2: triphenylsulfonium nonafluoro-n-
Butanesulfonate B-3: 4-n-butoxy-1-naphthyltetrahydro
Thiophenium nonafluoro-n-butanesulfonate B-4: bis (4-t-butylphenyl) iodonium
Nonafluoro-n-butanesulfonate, B-5: trifluoromethanesulfonylbicyclo [2.
2.1] Hept-5-ene-2,3-dicarbodiimideAcid diffusion controller C-1: tri-n-octylamine C-2: dicyclohexylmethylamine C-3: 1- (2'-hydroxyethyl) piperazine C-4: 4-hydroxyquinolineOther additives D-1: t-butyl deoxycholate (the following formula (18)
reference)

[0106]

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D-2: di-tert-butyl 1,3-adamantanedicarboxylate Solvent E-1: 2-heptanone E-2: ethyl 2-hydroxypropionate E-3: propylene glycol monoethyl ether acetate E-4 : Ethyl 3-ethoxypropionate

[0108]

[Table 1]

[0109]

[Table 2]

[0110]

[Table 3]

[0111]

The radiation-sensitive resin composition of the present invention is excellent in storage stability and, as a chemically amplified resist, has high transparency to radiation and excellent resolution, as well as dry etching resistance, sensitivity, and the like. It is also excellent in pattern shape and the like, and can be used very suitably in the manufacture of semiconductor devices that are expected to be further miniaturized in the future.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 45/00 C08L 45/00 H01L 21/027 H01L 21/30 502R (72) Inventor Shinichiro Iwanaga Central Tokyo 2-24-11 Tsukiji-ku, Japan JS R Co., Ltd. (72) Inventor Hiroyuki Ishii 2-1-2, Tsukiji, Chuo-ku, Tokyo Inside JS R Co., Ltd. No. 11-24 Inside JSR Corporation

Claims (1)

[Claims] (A) A copolymer having a repeating unit (I), a repeating unit (II) and a repeating unit (III-1) represented by the following general formula (1) and a copolymer represented by the following general formula (2) An alkali-insoluble or sparingly-soluble acid-dissociable group-containing resin selected from the group of copolymers having a repeating unit (I), a repeating unit (II) and a repeating unit (III-2), A radiation-sensitive resin composition comprising: a resin which becomes alkali-soluble when a labile group is dissociated; and (B) a radiation-sensitive acid generator. Embedded image Embedded image [In the general formulas (1) and (2), A and B each independently represent an acid-dissociable organic group having 20 or less carbon atoms which dissociates in the presence of a hydrogen atom or an acid to form an acidic functional group. And at least one of A and B is the acid dissociable organic group, X and Y each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbons, n is an integer of 0 to 3, R ¹ represents a hydrogen atom, a methyl group or a methylol group, R ² represents a divalent hydrocarbon group having ³ to 15 carbon atoms having an alicyclic group, and R ³ represents 3 carbon atoms having an alicyclic group. ~
It represents 15 trivalent hydrocarbon groups. ]