JP2002303982A - Resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chemical amplification type resist composition giving a resist pattern having excellent transparency to radiation, dry etching properties, sensitivity, resolution, flatness, heat resistance, etc. SOLUTION: The resist composition contains a fluorine-containing polymer (A) containing a polymerization unit which is based on a fluorine-containing diolefin (a) (e.g. CF2 =CFCF2 CH2 CH2 CH=CH2 ) and which yields a cyclic structure by polymerization and further containing a polymerization unit based on a monomer having a blocked acid group (e.g. CF2 =CFO(CF2 )3 COOC(CH3 )3 ), an acid generating compound (B) which generates an acid when irradiated with light and an organic solvent (C).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel fluorine-containing resist composition. More specifically, KrF, Ar
Far ultraviolet rays F laser, vacuum ultraviolet rays such as F _2, X-ray,
The present invention relates to a chemically amplified resist composition useful for fine processing using various radiations such as an electron beam.

[0002]

2. Description of the Related Art In recent years, in a manufacturing process of a semiconductor integrated circuit, a photo resist material having a high resolution and a high sensitivity has been demanded along with miniaturization of a circuit pattern. In order to make a circuit pattern finer, it is essential to use an exposure light source having a shorter wavelength. Polyvinylphenol resins, alicyclic acrylic resins, polynorbornene resins and the like have been proposed for lithography applications using excimer lasers of 250 nm or less, but their resolution and sensitivity are not sufficient.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide excellent transparency to radiation, excellent dry etching, sensitivity,
An object of the present invention is to provide a chemically amplified resist composition which provides a resist pattern having excellent resolution, flatness, heat resistance and the like.

[0004]

Means for Solving the Problems The present invention provides the following formula (1)
A fluorinated polymer containing a cyclized polymer unit based on a fluorinated diolefin (a1) and a polymer unit based on a monomer (a2) having an acidic group blocked by a blocking agent that is cleaved by an acid ( 0.1 to 20 parts by mass of the acid generating compound (B), which generates an acid upon irradiation with light, and 10 parts by mass of the organic solvent (C) with respect to 100 parts by mass of A).
Provided is a resist composition containing 0 to 1000 parts by mass.

[0005] _{^{CF 2 = CR 1 QCR 2 =}} CH 2 ··· (1) wherein, R ^1, R ² each independently represent a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, Q is carbon There are several to five divalent organic groups.

In the present invention, the fluoropolymer (A)
Contains a cyclized polymerization unit based on a fluorinated diolefin (a1) and a polymerization unit based on a monomer (a2) having an acidic group blocked by a blocking agent that is cleaved by an acid.

As the fluorine-containing diolefin (a1),
It is a compound represented by the formula (1). Specific examples thereof include the following compounds. Here, n represents an integer of 2 to 5. CF ₂ = CF (CH ₂ ) _n CH = CH ₂ , CF ₂ = CFO
(CH ₂ ) _n CH = CH ₂ , CF ₂ = CF (CF ₂ ) _n CH =
CH ₂ , CF ₂ = CFO (CF ₂ ) _n CH = CH ₂ , CF ₂ =
CF (CH ₂ ) _n C (CH ₃ ) = CH ₂ , CF ₂ = CFO
(CH ₂ ) _n C (CH ₃ ) = CH ₂ , CF ₂ = CF (CF ₂ )
_n C (CH ₃ ) = CH ₂ , CF ₂ ＣＦCFO (CF ₂ ) _n C (C
_{H 3) = CH 2, CF} 2 = C (CF 3) (CH 2) n CH = C
_{H 2, CF 2 = C (} CF 3) O (CH 2) n CH = CH 2, C
_{F 2 = C (CF 3)} (CF 2) n CH = CH 2, CF 2 = C
(CF ₃ ) O (CF ₂ ) _n CH = CH ₂ , CF ₂ = CF (C
H ₂ ) _n OCH = CH ₂ , CF ₂ ＣＦCF (CH ₂ ) _n OC (C
H ₃₎ = CH _2.

The acidic group (X) contained in the monomer (a2) having an acidic group blocked by a blocking agent that is cleaved by an acid is a carboxyl group, a sulfo group, a fluoroalkyl group or a fluoroalkylene group. And a hydroxyl group bonded to an aryl group. As the acidic group, a hydroxyl group bonded to a carbon atom to which a carboxyl group or a trifluoromethyl group is bonded, and a hydroxyl group bonded to a phenyl group are more preferable, and a hydroxyl group and a phenyl group bonded to a carbon atom bonded to two trifluoromethyl groups are preferable. Most preferred is a hydroxyl group attached to a group. A substituent may be bonded to the aryl group or the phenyl group, and the substituent is preferably a halogen atom, and more preferably a fluorine atom.

In the present invention, the monomer (a2) having an acidic group blocked by the blocking agent can be obtained by reacting the monomer (a2 ') having an acidic group with an alcohol, a carboxylic acid or the like.

Examples of the monomer (a2 ') having an acidic group include a compound represented by the following formula (2). CY ₂ = C (R ³ )-(O) _k1 -R ⁴ -Z ¹ (2) In the formula (2), Y represents a hydrogen atom or a fluorine atom;
³ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; R ⁴ is a single bond, a linear alkylene group having 1 to 8 carbon atoms;
8 branched alkylene group, a trifluoromethyl group two bonded carbon atoms or 1-4 phenylene groups fluorine atom-substituted, Z ¹ is a carboxyl group or a hydroxyl group, represents. k ₁ represents 0 or 1. As —R ⁴ —Z ¹ , a carbon atom in which two trifluoromethyl groups are bonded to a hydroxyl group (hereinafter referred to as a 1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl group or an HTTE group) ) Or a 4-hydroxyphenyl group substituted with 1 to 4 fluorine atoms.

Specific examples of the monomer (a2 ') having an acidic group include the following compounds. In the following, Ph ^3F represents a trifluorophenylene group, Ph ^4F represents a tetrafluorophenylene group, and the hydroxyl group is substituted at the 4-position. m is an integer of 2 to 6, n is an integer of 0 to 8, p
Represents an integer of 0 to 10. _{CH 2 = CH- (CH 2)} n -C (CF 3) 2 OH, CH 2 =
_{CH-O (CH 2) m} -C (CF 3) 2 OH, CH 2 = CH
_{- (CH 2) n -C (} CH 3) (CF 3) OH, CH 2 = C
_{H-O (CH 2) m} -C (CH 3) (CF 3) OH, CH 2
ＣＨCHOC (CH ₃ ) ₂ OH, CH ₂ ＣＨCHOC (C
_{2 H 5) 2 OH, CH} 2 = CH- (CH 2) n -Ph 3F -O
_{H, CH 2 = CH- (CH} 2) n -Ph 4F -OH, CH 2 =
_{C (CH 3) - (CH} 2) n -Ph 3F -OH, CH 2 = C
_{(CH 3) - (CH 2} ) n -Ph 4F -OH, CH 2 = C (C
_{2 H 5) - (CH 2} ) n -Ph 3F -OH, CH 2 = C (C 2 H
_{5) - (CH 2) n} -Ph 4F -OH, CF 2 = CF- (CF
_{2) n -C (CF 3)} 2 OH, CF 2 = CF-O (CF 2) m
_{-C (CF 3) 2 OH,} CF 2 = CF- (CF 2) n -C
_{(CH 3) (CF 3)} OH, CF 2 = CF-O (CF 2) m
_{-C (CH 3) (CF 3} ) OH, CF 2 = CF- (CF 2)
_{^{n -Ph 3F -OH, CF 2 =}} CF- (CF 2) n -Ph 4F -
_{OH, CF 2 = C (CF} 3) - (CF 2) n -Ph 3F -O
_{H, CF 2 = C (CF} 3) - (CF 2) n -Ph 4F -OH,
_{CH 2 = CH- (CH 2)} p -COOH, CF 2 = CF-
(CF _{2) p} -COOH.

In addition to the above, cyclic monomers such as norbornene to which an HTTE group is bonded, other carboxyl group-containing monomers such as methacrylic acid, CF ₂ ＣＦCFO (CF ₂ )
_n OR (n is 2 to 6, R is an ethyl group or a tert-butyl group) and the like.

The blocking agent for blocking the acidic group of the monomer (a2 ') having an acidic group is efficiently deblocked by the acid-generating compound (B) which generates an acid upon irradiation with light, thereby forming the acidic group. The group is not particularly limited as long as it is a group that is formed and makes the fluoropolymer (A) soluble in an alkaline developer. As the blocking agent, usually, a residue obtained by removing an alcoholic hydroxyl group of an alcohol (for example, an alkyl group,
Alkoxyalkyl group), an acyl group, a cyclic ether group and the like. Particularly, an alkyl group having 1 to 6 carbon atoms, an alkoxyalkyl group having 1 to 8 carbon atoms, a pivaloyl group, a tetrahydropyranyl group and the like are preferable.

In the present invention, the cyclized polymerization unit based on the fluorinated diolefin (a1) in the fluorinated polymer (A) contains a cyclic structure represented by the following formula (3) and / or (4).

[0015]

Embedded image

The fluorinated polymer (A) is obtained by copolymerizing a fluorinated diolefin (a1) and a monomer (a2) having an acidic group blocked by a blocking agent. The fluorinated diolefin (a1) is cyclized when polymerized to give polymerized units having the cyclic structure of the above (3) or (4).

The fluorinated polymer (A) may be a polymer based on another monomer (a3) other than the cyclized polymer unit based on the monomer (a1) and the polymer unit based on the monomer (a2) as long as the properties thereof are not impaired. It is also preferred to contain units.

Other monomers (a3) include α-olefins such as ethylene, propylene and isobutylene, fluorinated olefins such as tetrafluoroethylene and hexafluoropropylene, methyl (meth) acrylate, and (meth) acrylic acid. (Meth) acrylic esters such as ethyl, vinyl esters such as vinyl acetate, vinyl benzoate and vinyl adamanylate; vinyl ethers such as ethyl ether and cyclohexyl vinyl ether; cyclic olefins such as cyclohexene, norbornene and norbornadiene; Maleic acid, vinyl chloride and the like can be mentioned. The ratio of the polymerization unit based on the other monomer (a3) is preferably 15 mol% or less.

In the fluorinated polymer (A), the ratio of copolymerization of the cyclized polymerization unit based on the monomer (a1) and the polymerization unit based on the monomer (a2) is as follows.
It is preferable that cyclized polymerization unit based on 1) / polymerization unit based on monomer (a2) = 50/25 to 75/25 (mol%). If the amount of the cyclized polymerization unit based on the monomer (a1) is too small, the light transmittance tends to decrease. If the content of the cyclized polymerization unit based on the monomer (a1) is too high, the developability of the resist composition tends to decrease. Becomes

The molecular weight of the fluoropolymer (A) is not particularly limited as long as it can be uniformly dissolved in an organic solvent as described below and can be uniformly applied to a substrate. 100,000 is preferred, 2
2,000 to 20,000 is more preferable. Number average molecular weight is 1000
If it is less than 30, the obtained resist pattern becomes defective, the residual film ratio after development is reduced, and the shape stability during pattern heat treatment is reduced. If the number average molecular weight exceeds 100,000, the coating properties of the resist composition may be poor or the developability may be reduced.

The fluoropolymer (A) can be obtained by copolymerizing the monomers under a polymerization initiation source. Further, the monomer (a1) and the monomer having an acidic group (a
2 ′) to produce a fluorinated polymer (A ′), and then block the acidic groups in the fluorinated polymer (A ′) with a blocking agent to form the fluorinated polymer (A). It is also preferable to obtain

The polymerization initiation source is preferably one that causes the polymerization reaction to proceed radically, and examples thereof include a radical generator, light, and ionizing radiation. The polymerization initiator is preferably a radical generator, such as organic peroxides such as perfluorobenzoyl peroxide, benzoyl peroxide and di (tert-butyl) peroxide, azo compounds such as azobisisobutyronitrile, and persulfates such as ammonium persulfate. Is mentioned.

The polymerization method includes bulk polymerization in which the monomer is polymerized as it is, fluorinated hydrocarbon in which the monomer is dissolved, chlorohydrocarbon, fluorinated chlorohydrocarbon, alcohol,
Solution polymerization in which polymerization is performed in an organic solvent such as a hydrocarbon, suspension polymerization in which an appropriate organic solvent is present in an aqueous medium in the presence or absence thereof, and emulsion polymerization in which an emulsifier is added in an aqueous medium to perform polymerization. Can be

In the present invention, the acid generating compound (B) is
Generates acids upon exposure to light. The generated acid cleaves the block group in the fluoropolymer (A), so that the exposed portion of the resist film becomes easily soluble in an alkaline developer, and has an effect of forming a positive resist pattern. As the acid generating compound (B), an acid generating compound used in an ordinary chemically amplified resist material can be employed. Specific examples include onium salts, halogen-containing compounds, diazoketone compounds, sulfone compounds, sulfonic acid compounds, and the like.

Examples of the onium salt include an iodonium salt, a sulfonium salt, a phosphonium salt, a diazonium salt, a pyridinium salt and the like. Specific examples of onium salts include diphenyliodonium triflate, diphenyliodonium pyrene sulfonate, diphenyliodonium dodecylbenzenesulfonate, and bis (4-ter
t-butylphenyl) iodonium triflate, bis (4-tert-butylphenyl) iodonium dodecylbenzenesulfonate, triphenylsulfonium triflate, triphenylsulfonium hexafluoroantimonate, 1- (naphthylacetomethyl) thiolanium triflate, cyclohexyl Methyl (2-oxocyclohexyl) sulfonium triflate, dicyclohexyl (2-oxocyclohexyl) sulfonium triflate, dimethyl (4-hydroxynaphthyl) sulfonium tosylate, dimethyl (4-hydroxynaphthyl) sulfonium dodecylbenzenesulfonate, dimethyl (4-hydroxy Naphthyl) sulfonium naphthalene sulfonate, triphenylsulfonium camphorsulfonate, 4-hydroxyphenyl) and benzyl methyl sulfonium toluene sulfonates.

Examples of the halogen-containing compound include a haloalkyl group-containing hydrocarbon compound and a haloalkyl group-containing heterocyclic compound. Specific examples include phenyl-bis (trichloromethyl) -1,3,5-triazine and methoxyphenyl-bis (trichloromethyl) -1,3,3.
5-triazine, naphthyl-bis (trichloromethyl)
-Trichloromethyl substitution such as 1,3,5-triazine-
Examples include 1,3,5-triazine derivatives, 1,1-bis (4-chlorophenyl) -2,2,2-trichloroethane, and the like. Examples of the sulfone compound include α-ketosulfone, α-sulfonylsulfone, and α-
And diazo compounds. Specific examples include 4-tris (phenacyl) sulfone, mesitylphenacylsulfone, bis (phenylsulfonyl) methane, and the like.

Examples of the sulfonic acid compound include alkylsulfonic acid esters, alkylsulfonic acid imides, haloalkylsulfonic acid esters, arylsulfonic acid esters, and iminosulfonates. Specific examples include benzoin tosylate, 1,8-naphthalenedicarboxylic acid imide triflate, and the like.

In the present invention, the acid generating compound (B) is
One type may be used alone, or two or more types may be used in combination.

The organic solvent (C) in the present invention is not particularly limited as long as it dissolves the fluoropolymer (A) and the acid generating compound (B) which generates an acid upon irradiation with light. Specific examples include alcohols such as methyl alcohol and ethyl alcohol, ketones such as acetone, methyl isobutyl ketone and cyclohexanone, acetates such as ethyl acetate and butyl acetate, aromatic hydrocarbons such as toluene and xylene, and propylene glycol. Glycol monoalkyl ethers such as monomethyl ether and propylene glycol monoethyl ether; glycol monoalkyl ether esters such as propylene glycol monomethyl ether acetate and carbitol acetate;

The mixing ratio of each component in the resist composition of the present invention is 0.1 to 20 parts by mass of the acid generating compound (B) and 100 parts by mass of the fluoropolymer (A) and the organic solvent (C). ) Is 50 to 2000 parts by mass. Preferably, it is 0.1 to 10 parts by mass of the acid generating compound (B) and 100 to 1000 parts by mass of the organic solvent (C) based on 100 parts by mass of the fluoropolymer (A).

If the amount of the acid-generating compound (B) is less than 0.1 part by weight, the sensitivity and developability of the resist coating film decrease,
On the other hand, if it exceeds 10 parts by weight, the transparency to radiation decreases, and it tends to be difficult to obtain an accurate resist pattern.

The resist composition of the present invention comprises an acid-cleavable additive for improving pattern contrast, a surfactant for improving coatability, a nitrogen-containing basic compound for adjusting an acid generation pattern, and adhesion to a substrate. It is also preferable to add an adhesion aid for improving the storage stability, a storage stabilizer for improving the storage stability of the composition, and the like.

In the production of the resist composition of the present invention, the above components are uniformly mixed, and then the pore diameter is reduced to 0.2 to 0.2.
It is preferable to filter with a 2 μm filter. In particular, it is preferable to filter with a polytetrafluoroethylene (PTFE) filter.

The resist composition of the present invention is applied on a substrate such as a silicon wafer and then dried to form a resist film. Examples of the coating method include spin coating, flow coating, and roll coating. The formed resist film is irradiated with light through a mask on which a pattern is drawn, and then developed to form a pattern.

As the irradiation light, a g-line having a wavelength of 436 nm is used.
Ultraviolet light such as i-ray with a wavelength of 365 nm, K with a wavelength of 248 nm
rF excimer laser, ArF excimer laser with a wavelength of 193 nm, far ultraviolet ray of F ₂ excimer laser having a wavelength of 157 nm, vacuum UV, electron beams, X-rays and the like.

As the developing solution, an aqueous alkaline solution is used. Examples of the aqueous alkaline solution include aqueous solutions of sodium hydroxide, potassium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, triethylamine and the like.

The resist composition of the present invention can be used as a chemically amplified resist material for semiconductor integrated circuits (memory, CPU,
ASIC etc.).

[0038]

The present invention will be illustrated by the following examples, but the present invention is not limited to these examples.

[Synthesis Example of Fluoropolymer (A)] [Synthesis Example 1] 1,1,2,3,3-pentafluoro-
1,6-heptadiene (CF_Two= CFCF_TwoCH_TwoCH_TwoC
H = CH_Two6.8 of monomer a11)
g, CF _Two= CFO (CF_Two)_ThreeCOOC (CH_Three)_Three(After
Below, referred to as monomer a21) and 4.2 g of R113.
11 g was charged into a 50 cc glass pressure-resistant reactor.
It is. Next, as a polymerization initiator, perfluorobenzoyl
0.18 g of the oxide was added. Freeze and degas reactor
After that, polymerization was carried out in a constant temperature shaking bath at 70 ° C. for 6 hours.
The resulting polymerization solution was dropped into hexane to form the polymerization
After precipitating and separating the body, it was vacuum dried at 80 ° C. for 16 hours.
Was. Of a white powdery polymer (hereinafter referred to as polymer A1)
7.8 g were obtained.

The polymer A1 is a non-crystalline polymer having a fluorinated cyclic structure in the main chain, and has a molecular weight (measured by GPC) having a number average molecular weight (M _n ) of 1 in terms of polystyrene.
2,200, the weight average molecular weight ( _Mw ) was 26,600, and _Mw / _Mn = 2.18. The composition of polymer 1C measured by ¹⁹ FNMR was as follows: cyclized polymer units based on monomer a11 / polymerized units based on monomer a21 = 80/20
(Mol%) and the glass transition temperature was 155 ° C.

Synthesis Example 2 3.5 g of monomer a11
6.5 g of CF ₂ = CFO (CF ₂ ) ₄ COOC ₂ H ₅ (hereinafter, referred to as monomer a22) and 10 g of R113 were charged into a 50 cc glass pressure-resistant reactor. next,
0.14 g of perfluorobenzoyl peroxide was added as a polymerization initiator. After freezing and degassing the reactor, 7
The polymerization was carried out in a constant temperature shaking bath at 0 ° C. for 6 hours. The obtained polymer solution was dropped into hexane to precipitate and separate the formed polymer, and then dried under vacuum at 150 ° C. for 12 hours. 7.0 g of a white powdery polymer (hereinafter referred to as polymer A2)
was gotten.

The obtained polymer A2 is an amorphous polymer having a fluorinated cyclic structure in the main chain, and has a molecular weight (G
_Mn is 14,20 in terms of polystyrene.
0, _Mw was 41,300, and _Mw / _Mn = 2.91. The composition of polymer 2C measured by ¹⁹ FNMR was cyclized polymerization unit based on monomer a11 / polymerization unit based on monomer a22 = 69/31 (mol%), and the glass transition temperature was 82 ° C.

Synthesis Example 3 1,1,2,3,3-pentafluoro-1,7-octadiene (CF ₂ ＣＦCFCF ₂ C
4.5 g of H ₂ CH ₂ CH ₂ CH ＝ CH ₂ (hereinafter, referred to as monomer a12), CH ₂ ＣC (CH ₃ ) CH ₂ CH ₂ Ph ^4F
OCOOC (CH ₃ ) ₃ (hereinafter referred to as monomer a23)
Was charged into a glass pressure-resistant reactor having an internal volume of 50 cc. Next, 0.36 g of perfluorobenzoyl peroxide was added as a polymerization initiator. After freezing and degassing the reactor, polymerization was carried out for 7 hours in a constant temperature shaking bath at 70 ° C. The obtained polymer solution was dropped into hexane to precipitate and separate the polymer formed.
Vacuum dried at 0 ° C. for 16 hours. 8.2 g of a white powdery polymer (hereinafter, referred to as polymer A3) was obtained.

The polymer A3 is a non-crystalline polymer having a fluorine-containing cyclic structure in the main chain, and has a molecular weight (measured by GPC) of _Mn of 10,300 and _Mw of 21,900 in terms of polystyrene. And M _w / M _n = 2.13. ¹⁹
The composition of the polymer A3 measured by FNMR was the monomer a1
Cyclic polymerization unit based on 2 / polymerization unit based on monomer a23 = 72/28 (mol%), glass transition temperature is 155 ° C.
Met.

[Synthesis Example 4] 1,1,2,4,4,5,5
- heptafluoro-3-oxa-1,6-heptadiene _{(CF 2 = CFOCF 2 CF 2} CH = CH 2, hereinafter referred to as monomer a13) 4.2 g of _{the, CH 2 = CHCH 2 C (} C
5.8 g of F ₃ ) ₂ OCOOC (CH ₃ ) ₃ (hereinafter referred to as “monomer a24”) and 10.0 g of R113 were added to an inner volume of 5 g.
It was charged into a 0 cc glass pressure-resistant reactor. Next, 0.1 g of perfluorobenzoyl peroxide was used as a polymerization initiator.
12 g were added. After freezing and degassing the reactor, polymerization was carried out in a constant temperature shaking tank (70 ° C.) for 6 hours. The obtained polymer solution was dropped into hexane to precipitate and separate a polymer formed, and then dried in vacuum at 80 ° C. for 16 hours. 7.1 g of a white powdery polymer (hereinafter referred to as polymer A4) was obtained.

The polymer A4 is a non-crystalline polymer having a fluorine-containing cyclic structure in the main chain, and has a molecular weight (measured by GPC) of _Mn of 15,200 and _Mw of 35,000 in terms of polystyrene. And M _w / M _n = 2.30. ¹⁹
The composition of the polymer A4 measured by FNMR was the monomer a13
Cyclic polymerization unit based on / polymerization unit based on monomer a24 =
75/25 (mol%), glass transition temperature was 155 ° C.

Example 1 Polymer A synthesized in Synthesis Example 1
1 and 5 g of trimethylsulfonium triflate (hereinafter, referred to as acid generating compound B1) are dissolved in 7 g of propylene glycol monomethyl ether acetate (hereinafter, referred to as organic solvent C1).
The mixture was filtered through a TFE filter to produce a resist composition. After spin-coating the above resist composition on a silicon substrate treated with hexamethyldisilazane,
Heat treatment on the silicon substrate for 0.4 min.
Was formed. When the absorption spectrum of this resist film was measured with an ultraviolet-visible light photometer, the transmittance at 193 nm was 48%.

The silicon substrate on which the above-described resist film was formed was placed in a nitrogen-exposed exposure experiment apparatus, and a mask on which a pattern was drawn with chromium on a quartz plate was adhered thereon.
Irradiate ArF excimer laser light through the mask,
Then, it baked at 100 degreeC for 2 minutes. In a 2.38% by mass aqueous solution of tetramethylammonium hydroxide, 23
After developing at ℃ for 3 minutes, it was washed with pure water for 1 minute. As a result, only the exposed portion of the resist film was dissolved and removed in the developing solution at an exposure amount of 19 mJ / cm ² , and a positive 0.25 μm line and space pattern was obtained.

Example 2 Polymer A synthesized in Synthesis Example 2
2 g and 5 g of the acid generating compound B1 are mixed with 7 g of the organic solvent C1.
g, and filtered through a PTFE filter having a pore diameter of 0.1 μm to produce a resist composition. The above resist composition was spin-coated on a silicon substrate treated with hexamethyldisilazane, and then heated at 80 ° C. for 2 minutes,
A 0.5 μm-thick resist film was formed on a silicon substrate. When the absorption spectrum of this film was measured with an ultraviolet-visible light photometer, the transmittance at 193 nm was 59%.

An exposure test was carried out in the same manner as in Example 1. As a result, only the exposed portion of the resist film was dissolved and removed in a developing solution at an exposure amount of 20 mJ / cm ² , and a positive 0.25 μm line and space pattern was obtained. Was done.

Example 3 Polymer A synthesized in Synthesis Example 3
3 g and 5 g of the acid generating compound B1 are mixed with 7 g of the organic solvent C1.
g, and filtered through a PTFE filter having a pore diameter of 0.1 μm to produce a resist composition. The above resist composition was spin-coated on a silicon substrate treated with hexamethyldisilazane, and then heated at 80 ° C. for 2 minutes,
A resist film having a thickness of 0.55 μm was formed on a silicon substrate. When the absorption spectrum of this film was measured with an ultraviolet-visible light photometer, the transmittance at 193 nm was 50%.

An exposure test was carried out in the same manner as in Example 1. As a result, only the exposed portion of the resist film was dissolved and removed in a developing solution at an exposure amount of 18 mJ / cm ² , and a positive 0.25 μm line and space pattern was obtained. Was done.

Example 4 Polymer A synthesized in Synthesis Example 4
4g and 5 g of the acid generating compound B1 are mixed with 7 g of the organic solvent C1.
g, and filtered through a PTFE filter having a pore diameter of 0.1 μm to produce a resist composition. The above resist composition was spin-coated on a silicon substrate treated with hexamethyldisilazane, and then heated at 80 ° C. for 2 minutes,
A 0.58 μm-thick resist film was formed on a silicon substrate. When the absorption spectrum of this film was measured with an ultraviolet-visible light photometer, the transmittance at 193 nm was 52%.

An exposure test was carried out in the same manner as in Example 1. As a result, only the exposed portion of the resist film was dissolved and removed in a developing solution at an exposure amount of 20 mJ / cm ² , and a positive 0.25 μm line and space pattern was obtained. Was done.

[Examples 5 to 8] Table 1 shows the results of measuring the etching resistance of the resist films of Examples 1 to 4. The etching resistance test and evaluation are as follows. The etching rate was measured with an argon / octafluorocyclobutane / oxygen mixed gas plasma, and when the novolak resin was 1.0, ◎: less than 1.2, Δ: 1.2 to less than 1.4, Those having a value of 1.4 or more were evaluated as x.

[0056]

[Table 1]

[0057]

The resist composition of the present invention, as a chemically amplified resist, can easily form a resist pattern which is particularly excellent in radiation transparency, dry etching property, sensitivity, resolution, flatness, heat resistance and the like. .

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Shinji Okada 1150 Hazawa-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Inside Asahi Glass Co., Ltd. (72) Inventor Shunichi Kodama 1150 Hazawa-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture F inside Asahi Glass Co., Ltd. Term (reference) 2H025 AA01 AA02 AA09 AA10 AA18 AB16 AC04 AC05 AC06 AC08 AD03 BE00 BE10 BG00 CB08 CB14 CB41 CC03 FA17 4J100 AB07Q AD13Q AE09Q AE78P AJ01Q AJ03Q AS13P BA03 BB07 BB12 BB18 CA04

Claims (2)

[Claims] 1. A polymerization based on a cyclized polymerization unit based on a fluorinated diolefin (a1) represented by the following formula (1) and a monomer (a2) having an acidic group blocked by a blocking agent that is cleaved by an acid. And 0.1 to 20 parts by mass of an acid generating compound (B) which generates an acid upon irradiation with light, and 100 parts by mass of an organic solvent (C) based on 100 parts by mass of the fluoropolymer (A) containing A resist composition, comprising -1000 parts by mass. _{^{CF 2 = CR 1 QCR 2 =}} CH 2 ··· (1) wherein, R ^1, R ² each independently represent a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, Q is 2 carbon atoms Five divalent organic groups. 2. The method according to claim 1, wherein the fluorinated diolefin (a1) is
F ₂ = CFCF ₂ CH ₂ CH ₂ CH = CH ₂ or CF ₂ = CF
The resist composition according to claim 1 is _{OCF 2 CF 2 CH = CH 2} .