JPH08254828A - Resist composition - Google Patents

Abstract

PURPOSE: To provide a compsn. excellent in resist characteristics such as sensitivity, resolution, heat resistance, etching resistance and pattern shape and fit for lithography using far UV of short wavelength by incorporating a polymer having specified structural units and a radiation sensitive component which forms an acid when irradiated with activated radiation. CONSTITUTION: This compsn. contains a polymer having structural units represented by formulae I-III and a radiation sensitive component which forms an acid when irradiated with activated radiation. 13 In the formulae I-III, each of R<1> -R<3> is H, 1-4C substitutable alkyl, etc., R<4> is a group represented by formula IV, R<5> is straight chain, branched or cyclic substitutable alkyl, etc., (k), (m) and (n) show the ratio among the structural units, k+m+n=1, 0<k<0.95, 0<m<0.95, 0.05<=n<=0.6 and 0.1<=k/(k+m)<1. In the formula IV, each of R<6> -R<10> is H, halogen, etc., and has <=12 carbon atoms and A is a single bond or a divalent org. 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 composition, and more specifically, it is useful for ultrafine processing of semiconductor devices using radiation such as deep ultraviolet rays such as excimer laser, charged particles such as X-ray and electron beam. Radiation-sensitive composition suitable as another resist.

[0002]

2. Description of the Related Art When manufacturing a semiconductor device, a resist is applied to the surface of a silicon wafer to form a photosensitive film, which is irradiated with light to form a latent image, which is then developed to form a negative or positive image. The image is obtained by using the lithographic technology. By the way, IC, LSI, and VLSI
Due to the high integration, high density and miniaturization of semiconductors,
A technique for forming a fine pattern of 5 μm or less is required. However, it is extremely difficult to form a fine pattern of 0.5 μm or less with high precision by conventional lithography using near-ultraviolet rays and visible rays, and the yield is significantly reduced. Therefore, in order to increase the resolution of exposure, conventional photolithography that uses near-ultraviolet light having a wavelength of 350 to 450 nm is used, and in order to increase the resolution of exposure, far-ultraviolet light having a short wavelength (short-wavelength ultraviolet light), krypton fluoride laser (KrF excimer laser light). A wavelength of 248 nm) and a lithography technique using an electron beam are being studied.
A conventional novolak resin is used as a base polymer in lithography using near-ultraviolet light. Although this resin has a good transmittance for ultraviolet light having a wavelength of 350 to 450 nm, it has a long wavelength. UV rays and KrF
Since the transmissivity of excimer laser light is extremely deteriorated, when novolac resin is used as the base polymer, there are known problems such as insufficient sensitivity and poor pattern shape. . For the purpose of improving the poor transmittance, a chemically amplified resist using a polyvinylphenol derivative as a base polymer has been investigated (Japanese Patent Publication No. 27660/1990), but the pattern shape and the resolution are still considered. It has not yet met the requirements. Further, as a recent example, a method of using a hydrogenated polyvinylphenol derivative as a base polymer for the purpose of further improving the transmittance (Japanese Patent Laid-Open No. 5-249673).
No. gazette) is known. Although the resolution is considerably improved by this improvement, further improvement is required for the more advanced required properties of the resist, particularly the resolution, the pattern shape and the etching resistance.

[0003]

Under the circumstances, the inventors of the present invention have made diligent studies to solve the above-mentioned problems, and as a result, did not introduce a vinylphenol unit having a substituted allyloxy group and a substituent. It was found that a resist composition having excellent resist properties can be obtained by using a polymer having a vinylphenol unit and a methacrylate unit,
The present invention has been completed based on this finding.

[0004]

According to the present invention, the general formulas (1), (2) and (3) are thus obtained.

[Chemical 6]

[Chemical 7]

Embedded image (In the formulas (1) to (3), R ^{1 to} R ³ are each independently a hydrogen atom, a substituted alkyl group having 1 to 4 carbon atoms, a halogen atom, a cyano group or a nitro group, and R ⁴ is the following formula. (4)

[Chemical 9] (In the formula (4), R ^{6 to} R ¹⁰ may be the same or different from each other, and a hydrogen atom, a halogen atom, a nitro group, a cyano group,
It is a substitutable alkyl group, a substitutable alkenyl group, a substitutable alkadienyl group or a substitutable vinyl group, and at least two of R ^{6 to} R ¹⁰ are substituents other than hydrogen atoms. R
⁶ and R ⁹ , R ⁸ and R ¹⁰ , and R ⁹ and R ¹⁰ may independently form a ring. Further, each of R ^{6 to} R ¹⁰ independently has 12 or less carbon atoms. A is a single bond or a divalent organic group. And R ⁵ is a linear, branched or cyclic, substitutable alkyl group or the following formula (5)

[Chemical 10] (In the formula (5), R ¹¹ is a substitutable alkyl group or a substitutable alkenyl group, R ^{12 to} R ¹⁵ are hydrogen atoms, halogen atoms or substitutable alkyl groups, and at least one of R ^{12 to} R ¹⁵ is selected. Is a hydrogen atom, and B is a divalent organic group.). In the formulas (1) to (3), k, m, and n represent the proportions of the respective constituent units, and when the sum of the proportions of the respective constituent units in the polymer is 1, 0 <k <0.95,0. <M <0.9
5, 0.05 ≦ n ≦ 0.6, 0.1 ≦ k / (k + m) <
It is 1. The present invention provides a resist composition comprising a polymer having a structural unit represented by the formula (4) and a radiation-sensitive component that produces an acid when exposed to activating radiation.

The present invention will be described in detail below. The polymer used in the present invention is a polymer having the structural units represented by the formulas (1), (2) and (3) as essential constituent units. This polymer may be a block copolymer or a random copolymer. The lower limit of the weight average molecular weight of this polymer is usually 1,000, preferably 2,000, and the upper limit is usually 100,000, preferably 20,000. If it deviates from this range, the resolution may decrease.

R in equations (1), (2) and (3)
Specific examples of ¹ , R ² and R ³ are hydrogen atom; methyl group, ethyl group, n-propyl group, isopropyl group, n-
1 carbon atom such as butyl group, s-butyl group, t-butyl group
~ 4 alkyl groups and substitution products in which one or more hydrogen atoms of these alkyl groups are substituted with halogen atoms, alkoxy groups, etc .; halogen atoms such as fluorine, chlorine, bromine, iodine; cyano groups; nitro groups. .

R ⁴ in the formula (1) is a group represented by the above formula (4), and this group may be any group as long as it functions as an acid labile group which is decomposed by an acid. Specific examples of R ^{6 to} R ¹⁰ in the formula (4) include hydrogen atom, nitro group, cyano group, halogen atom such as chlorine atom and bromine atom; methyl group, ethyl group, propyl group, butyl group, Amyl group, cyclopentyl group, cyclohexyl group,
Cycloheptyl group, 1-methylcyclopentyl group, 2-
Substitutable alkyl groups such as ethylcyclopentyl group, 1-ethylcyclohexyl group, 2-methylcyclohexyl group; vinyl group, 1-propenyl group, allyl group, 1-butenyl group, 3-butenyl group, 1-pentenyl group, 2- Pentenyl group, 4-pentenyl group, hexenyl group, 2-cyclobutenyl group, 2-cyclopentenyl group, 1-methyl-
2-cyclopentenyl group, 2-cyclohexenyl group, 3
-Substitutable alkenyl group such as methyl-2-cyclohexenyl group; 2,4-cyclopentadienyl group, 1-methyl-2,4-cyclopentadienyl group, 3-methyl-2,
4-cyclopentadienyl group, 3,4-dimethyl-2,
Substitutable cycloalkadienyl groups such as 4-cyclopentadienyl group, 2,5-cyclohexadienyl group and 3,5-dimethyl-2,5-cyclohexadienyl group; vinyl group, 1-propenyl group, 1 -Buten-1-yl group, 1-
Examples thereof include substituted vinyl groups such as butene-2-yl group and 2-buten-2-yl group. Further, R ⁶ and R ⁹ may be bonded to each other to form a ring such as cyclohexene or cyclopentene. Similarly, R ⁸ and R ¹⁰ and R ⁹ and R ¹⁰ may also form a ring. However, the cyclization is not preferable because the sensitivity may decrease. In the specific examples of the substituent, propyl represents n-propyl and isopropyl, and butyl is n-butyl, isobutyl, s-butyl, t.
-Butyl, and amyl represents pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylpropyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl. Preferred examples of the substituent other than hydrogen atom of R ^{6 to} R ¹⁰ in the formula (4) are a halogen atom and each substituent having 1 to 4 carbon atoms, particularly an alkyl group having 1 to 4 carbon atoms and a carbon number. 1 to
4 alkenyl groups are preferred.

A in the formula (4) is a single bond or a divalent organic group, and in the case of a single bond, it is the same as the formula (4).
A preferred example of the divalent organic group is the following formula (6)

[Chemical 11] (In the formula, D is a single bond or a divalent organic group having 1 to 10 carbon atoms, Y is a single bond, a divalent organic group having 1 to 4 carbon atoms,
-O -, - CO -, - CO 2 - , Z is a -CO-, r is an integer of 0 to 3. However, when r is 1 to 3, Z is bonded to an oxygen atom in the formula, and when r is 0, D is bonded to an oxygen atom in the formula. ) The group represented by is mentioned.

Specific examples of the divalent organic group represented by D in the above formula (6) include methylene, ethylene, propane-1,
3-diyl, propane-1,2-diyl, butane-1,
4-diyl, butane-2,2-diyl, pentane-1,
5-diyl, hexane-1,6-diyl, cyclopentylene, cyclohexylene, 2-methylcyclohexylene, or other straight-chain, branched or cyclic, substitutable alkylene; vinylene, propenylene, butynylene, hexynylene, 2-
Chloropentynylene, 3-ethylcyhexenylene, cyclohexenylene, 2-chlorocyclohexenylene, -C
H = CHCH = CH -, - CH 2 C = CHCH 2 CH =
Straight chain such as CH-, -CCl = CH-CH = CCl-
In addition to branched or cyclic substitutable alkenylene, etc., the formula (7) at or at one end of these residues,

[Chemical 12] (In the formula, R ^{16 to} R ¹⁸ are a halogen atom or an alkyl group having 1 to 4 carbon atoms), a divalent group represented by —O—, or —C.
_{O -, - CO 2 - -CH} 2 -O and divalent groups bond such as
_{-CH 2 -, - CH 2 -C} 6 H 4 -O-CH 2 -, - CH 2 -
_{C 6 H 4 -CH 2 -,} - CH 2 -C 6 H 4 - or may be in the form like. Specific examples of the divalent organic group of Y in the formula (6) include alkylene having 1 to 4 carbon atoms such as -O-, methylene, ethylene, vinylene, propenylene, butynylene, and alkenylene. Among these preferred examples of A, in addition to a single bond, -OCH ₂ CO-,
_{-OCH (CH 3) CO -,} - OC (CH 3) 2 CO-,
_{-OCCl 2 CO -, - OCH (} Ph) CO- ( in the formula (Ph) represents a phenyl group or less the same..), - OC
(Ph) ₂ CO− and the like, the following equation (8)

[Chemical 13] (In the formula, R ¹⁹ and R ²⁰ are a hydrogen atom, a halogen atom, a substitutable alkyl group, a substitutable alkenyl group, a substitutable phenyl group, or a substitutable aralkyl group, and each group has 10 carbon atoms.
It is the following. Further, these groups may have a substituent. Divalent group represented _{by), -OCH 2 -C 6 H 4} -O-
_{CH 2 CO -, - OCH (} C 2 H 3) -C 6 H 4 -O-CH 2
_{CO -, - OCH 2 - (} C 6 H 3 (CH 3)) - OCH
_{(CH 3) CO -, -} OCHCl-C 6 H 4 -O-CH 2 C
The following formula (9) such as O-

Embedded image (In the formula, R ^{21 to} R ²⁶ are a hydrogen atom, a halogen atom, a substitutable alkyl group and a substitutable alkenyl group, and each group has 4 or less carbon atoms. Further, these groups have a substituent. May be a) divalent group represented by. Among these, the group represented by the formula (8) is particularly preferable.

Specific examples of the substituents of the formulas (8) and (9) are the same as R ^{6 to} R ^{10 in the} formula (4) for the halogen atom, the substitutable alkyl group and the substitutable alkenyl group. As the substitutable aralkyl group, a benzyl group, a 4-hydroxybenzyl group, a 4-methylbenzyl group, a phenethyl group, a 3-methylphenethyl group, 2,4,4.
Examples thereof include 6-trimethylphenethyl group and 4-hydroxyphenethyl group.

R ⁵ in the formula (3) is a linear, branched or cyclic substitutable alkyl group or a group represented by the above formula (5), and specific examples thereof include a methyl group, an ethyl group, a propyl group, Butyl group, amyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, adamantyl group, norbornyl group, chloromethyl group, 2-hydroxyethyl group,
Substitutable alkyl group such as 2-bromoethyl group; 1-methylcyclopentyl group, 1-ethylcyclopentyl group, 1
Such as vinylcyclopentyl group, 1-methylcyclohexyl group, 1-methyl-3-methylcyclohexyl group, 1-methyl-4-chlorocyclohexyl group, 1-methylcycloheptyl group, 1-methyl-3-cyclohexenyl group Examples include groups represented by the above formula (5).

In the formula (5), R ¹¹ is a substitutable alkyl group or a substitutable alkenyl group, and R ^{12 to} R ¹⁵ are hydrogen atoms, halogen atoms or substitutable alkyl groups. Are the same as the halogen atom, the substitutable alkyl group and the substitutable alkenyl group of the above formula (4). In addition, R ¹¹ has 1 to 12 carbon atoms.
And R ^{12 to} R ¹⁵ preferably have about 1 to 4 carbon atoms.

[0013] Equation (5) in B is a divalent organic group, specific examples _{thereof, -CH 2 -, - C 2} H 4 -, - C 3 H 6
_{-, - C 4 H 8 -} , - C 5 H 10 - -C n H 2n , such as - in the alkylene or some or all halogen atoms of hydrogen atom represented, cyano group, hydroxyl group, the number of carbon atoms 1-4 alkyl group, an alkoxy group having 1 to 4 carbon atoms, -CHCl substituted alkenyl group having 2 to 5 carbon atoms -, - CH ₂ C
(CN) H -, - CH (CH 3) H -, - CH 2 C (CH
_{3) H -, - CH 2} C (CH 3) HCH 2 -, - C (OCH
_{3) H -, - CH 2} (CH = CH) CH 2 - optionally substituted alkylene, such as; -CH = CH -, - CH 2 CH = CH-,
_{-C (CH 3) = CH-} CH 2 -, - C (CH 3) = CH
Examples thereof include substitutable alkenylene such as Cl-.
In each of the specific examples of the substituent, propyl represents n-propyl and isopropyl, and butyl represents n-butyl, isobutyl and s.
-Butyl, t-butyl, amyl is pentyl, 1-
Methylbutyl, 2-methylbutyl, 3-methylbutyl,
1-ethylpropyl, 1,1-dimethylpropyl, 1,
Represents 2-dimethylpropyl and 2,2-dimethylpropyl.

Specific examples of the group represented by the above formula (4) include a 3-methyl-2-butenyloxycarbonylmethyloxy group, a 1-methyl-2-butenyloxycarbonylmethyloxy group, 1,1-dimethyl-2-propenyloxycarbonylmethyloxy group, 1,1-dimethyl-2-pentenyloxycarbonylmethyloxy group, 2-cyclohexenyloxycarbonylmethyloxy group, 4- (3-methyl-2-bu Tenyloxycarbonylmethyloxy) benzyloxy group, 4- (1-methyl-2-butenyloxycarbonylmethyloxy) benzyloxy group, 2- (1,1-dimethyl-2-propenyloxycarbonylmethyloxy) benzyloxy group Four
Examples thereof include a-(1,1-dimethyl-2-pentenyloxycarbonylmethyloxy) benzyloxy group.

The proportions of the structural units represented by the formulas (1), (2) and (3) are respectively represented by m, n and k, and when the total proportion of the constitutional units in the polymer is 1, it is usual. 0 <k <
0.95, 0 <m <0.95, 0.05 ≦ n ≦ 0.6,
0.1 ≦ k / (k + m) <1. When the proportion k of the structural unit represented by the formula (1) is small, sensitivity and resolution are deteriorated and the pattern shape is deteriorated. On the contrary, when the proportion k is too large, contrast tends to be deteriorated. Further, if the proportion m of the structural unit represented by the formula (2) is small, the etching resistance is lowered, and conversely, if it is too large, the solubility of the resist unexposed portion in the developing solution is increased. Therefore, the ratio of the unit represented by the formula (1) to the structural units represented by the formulas (1) and (2) (k /
(K + m)) has a lower limit of usually 0.1 or more, preferably 0.2 or more, more preferably 0.3 or more, and an upper limit of usually less than 1, preferably 0.8 or less, more preferably 0.7. It is the following.

Ratio of the total of the structural units represented by the formulas (1) and (2) to the whole resin ((k + m) / (k + m +)
n)) is not particularly limited as long as the above conditions are satisfied, but is preferably 0.4 to 0.95, more preferably 0.60 to 0.85. If this ratio is too small (that is, if there are too many units of formula (3)), the etching resistance may decrease, and conversely if this ratio is too large (that is, there are too few units of formula (3)). If too much), the light transmittance may be decreased, and the sensitivity and resolution may be decreased. Therefore, the ratio k of the structural unit represented by the formula (3) has a lower limit of 0.05, preferably 0.1, and an upper limit of usually 0.6, when the total ratio of all structural units is 1. , And more preferably 0.5.

If the proportion of the structural unit represented by the formula (1) in the resin is high (usually, the proportion represented by (k / (k + m)) is 0.3 or more), the above formula ( The substituent R ⁵ in 3) does not have to be a group useful as an acid labile group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, and an n-group.
It usually does not function as an acid labile group such as butyl, 2-hydroxyethyl, 2-chloroethyl, etc. 1
Substituted alkyl groups whose positions are unsubstituted can be used.
On the other hand, when the ratio of the structural unit represented by the formula (1) in the resin is low (usually, the ratio represented by (k / (k + m)) is less than 0.3), R ⁵ is an acid labile group. The group represented by the above formula (5) is exemplified as a preferable example. Further, in the resin, R ⁵ of the structural unit represented by the formula (3) has an unsubstituted alkyl group which is unsubstituted at the 1-position and R ⁵ has a group represented by the formula (5) in the resin. It may exist.

Further, structural units other than the structural units represented by the above formulas (1), (2) and (3) (hereinafter referred to as other structural units) within a range that does not impair the effects of the present invention.
May be present in the polymer. The range in which the effect of the present invention is not impaired here is such that, when the total of the ratios of the structural units in the polymer is 1, the ratio of the other structural units usually has an upper limit of 0.2, preferably 0.1. is there.

The polymer containing the structural units represented by the above formulas (1), (2) and (3) used as the resin component in the present invention can be synthesized by a conventional method. For example, the following equation (10)

[Chemical 15] (In the formula (10), R ²⁷ is a hydrogen atom, a substituted alkyl group having 1 to 4 carbon atoms, a halogen atom, a cyano group or a nitro group.) And a hydroxystyrene-based monomer represented by the following formula: (11)

Embedded image (In the formula (11), R ³ and R ⁵ are the same as those in the above formula (3)), and then the formula (1
A method of introducing the group represented by the above formula (4) into the oxygen atoms of a part of the hydroxyl groups derived from (0).

The method of introducing the group represented by the above formula (4) depends on A of the group represented by the above formula (4). For example, the monomer represented by the formula (10) and the formula (11)
When a polysubstituted allyl halide is reacted with a copolymer represented by the formula (1) under basic conditions, a compound in which A in the formula (4) is a single bond is obtained, and a halogenated organic acid When a polysubstituted allyl ester is reacted, A of the above formula (4) is a group represented by the above formula (8), and a polysubstituted allyl ester of a halogenated alkylphenoxy organic acid is reacted. Then, the group in which A in the formula (4) is a group represented by the formula (9) is obtained.

The monomer represented by the formula (10) is 4
-Hydroxystyrene, 3-hydroxystyrene, 2-
Examples thereof include hydroxystyrene, α-methyl-4-hydroxystyrene, α-methyl-3-hydroxystyrene, α-methyl-2-hydroxystyrene and 4-hydroxy-3-methylstyrene.

Examples of the monomer represented by the formula (11) include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, t-amyl acrylate and 2-hydroxyethyl. Acrylate, 3-
Hydroxypropyl acrylate, chloromethyl acrylate, 1-methylcyclopentyl acrylate, 1-
Methyl cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, t-amyl methacrylate, 2-hydroxyethyl methacrylate, 3
-Hydroxypropyl methacrylate, bromoethyl methacrylate, 1-methylcyclopentyl methacrylate, 1-methylcyclohexyl methacrylate and the like are exemplified. Among these, straight chain alkyl (meth)
Acrylate, hydroxyalkyl (meth) acrylate and (meth) acrylate having a group represented by the above formula (5) are preferable examples.

Further, examples of the polysubstituted allyl halide used when introducing the group represented by the above formula (4) include:
1,1-dimethylallyl bromide, 1,2-dimethylallyl bromide, 2,3-dimethylallyl bromide, 3,3-dimethylallyl bromide, 1-methyl-
3-ethylallylbromide and the like are exemplified, and examples of the polysubstituted allyl ester of halogenated organic acid include:
3-methyl-2-butenyl bromoacetate, 1-methyl-2-butenyl bromoacetate, 1,1-dimethyl-2-propenyl bromoacetate, 1,1-dimethyl-2-pentenyl bromoacetate, 2-cyclohexenyl bromoacetate , 3-methyl-2-butenyl chlorooxalate, 2-butenyl bromoacetate, 1-methyl-2-propenyl bromoacetate and the like. Specific examples of the polysubstituted allyl ester of halogenated alkylphenoxy organic acid include 1-
Methyl-2-butenyl (4-bromomethyl) phenoxyacetate, 3-methyl-2-butenyl (4-bromomethyl) phenoxyacetate, 1,1-dimethyl-
Examples include 2-propenyl (4-bromomethyl) phenoxyacetate and 1,1-dimethyl-2-pentenyl (4-bromomethyl) phenoxyacetate.

Specific examples of the polymer used in the present invention include:
4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / methyl acrylate copolymer, 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxy Styrene / methyl methacrylate copolymer, 4-
(3-Methyl-2-butenyloxycarbonylmethyloxy) styrene / 3-hydroxystyrene / methylmethacrylate copolymer, 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl acrylate copolymer, 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate, 4- (3-methyl-2)
-Butenyloxycarbonylmethyloxy) styrene /
4-hydroxystyrene / ethyl methacrylate, 4-
(3-Methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2-hydroxyethyl methacrylate, 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4 /
Hydroxystyrene / 1-methylcyclohexyl methacrylate, 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate, 4- (1-methyl-2)
-Butenyloxycarbonylmethyloxy) styrene /
4-hydroxystyrene / ethyl methacrylate, 4-
(1-Methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2-hydroxyethylmethacrylate, 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4
Hydroxystyrene / 1-methylcyclohexyl methacrylate, 4- (1,1-dimethyl-2-propenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / methylmethacrylate copolymer, 4-
(1,1-Dimethyl-2-propenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / ethyl methacrylate copolymer, 4- (1,1-dimethyl-2-propenyloxycarbonylmethyloxy) styrene / 4-hydroxy Styrene / t-butyl acrylate copolymer, 4- (1,1-dimethyl-2-propenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / t-butyl methacrylate copolymer, 4
-(1,1-Dimethyl-2-propenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene /
1-methylcyclohexyl methacrylate copolymer, 4
-(2-Cyclohexenyloxycarbonylmethyloxy) styrene / 3-hydroxystyrene / ethylmethacrylate copolymer, 4- [4- (3-methyl-2-butenyloxycarbonylmethyloxy) benzyloxy]
Styrene / 4-hydroxystyrene / methylmethacrylate copolymer, 4- [4- (3-methyl-2-butenyloxycarbonylmethyloxy) benzyloxy] styrene / 4-hydroxystyrene / 1-methylcyclopentylmethacrylate copolymer , 4- [4- (3-methyl-2-butenyloxycarbonylmethyloxy) benzyloxy] styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate copolymer, 4- [4
-(1,1-Dimethyl-2-propenyloxycarbonylmethyloxy) benzyloxy] styrene / 3-hydroxystyrene / n-propylmethacrylate copolymer, 4- (3-methyl-2-butenyloxycarbonylcarbonyloxymethyl Oxy) styrene / 2-hydroxystyrene / methyl acrylate copolymer, 4- (3
Examples include -methyl-2-butenyloxycarbonyloxymethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate copolymer.

The acid generator (hereinafter referred to as PAG) used in the present invention is not particularly limited as long as it is a substance capable of generating a Bronsted acid or a Lewis acid when exposed to activating radiation, and may be an onium salt or a halogenated compound. Organic compounds,
Quinonediazide compound, α, α'-bis (sulfonyl)
Known compounds such as diazomethane compounds, α-carbonyl-α′-sulfonyldiazomethane compounds, sulfone compounds, organic acid ester compounds, organic acid amide compounds, and organic acid imide compounds can be used. Examples of onium salts include diazonium salts, ammonium salts, iodonium salts such as diphenyliodonium triflate, sulfonium salts such as triphenylsulfonium triflate, phosphonium salts, arsonium salts, and oxonium salts.

The halogenated organic compounds include halogen-containing oxadiazole compounds, halogen-containing triazine compounds, halogen-containing acetophenone compounds, halogen-containing benzophenone compounds, halogen-containing sulfoxide compounds, halogen-containing sulfone compounds,
Halogen-containing thiazole compounds, halogen-containing oxazole compounds, halogen-containing triazole compounds, halogen-containing 2-pyrone compounds, other halogen-containing heterocyclic compounds, halogen-containing aliphatic hydrocarbon compounds,
Examples thereof include halogen-containing aromatic hydrocarbon compounds and sulfenyl halide compounds.

Specific examples of the quinonediazide compound include:
1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester, 2,1-naphthoquinonediazide-4-sulfonic acid ester Ester, 2,1-benzoquinonediazide-5
Sulfonic acid ester of quinonediazide derivative such as sulfonic acid ester, 1,2-benzoquinone-2-diazide-4-sulfonic acid chloride, 1,2-naphthoquinone-2-diazide-4-sulfonic acid chloride, 1,2-
Sulfonic acid of quinonediazide derivative such as naphthoquinone-2-diazide-5-sulfonic acid chloride, 1,2-naphthoquinone-1-diazide-6-sulfonic acid chloride and 1,2-benzoquinone-1-diazide-5-sulfonic acid chloride Examples include chloride.

The α, α-bis (sulfonyl) diazomethane compounds include unsubstituted, symmetrically or asymmetrically substituted alkyl group, alkenyl group, aralkyl group,
Examples include α, α′-bis (sulfonyl) diazomethane having an aromatic group or a heterocyclic group. Specific examples of the α-carbonyl-α-sulfonyldiazomethane compound include an α- having an unsubstituted, symmetrically or asymmetrically substituted alkyl group, alkenyl group, aralkyl group, aromatic group, or heterocyclic group. Carbonyl-α '
-Sulfonyldiazomethane and the like.

Specific examples of sulfone compounds include unsubstituted, symmetrically or asymmetrically substituted alkyl groups,
A sulfone compound, a disulfone compound, or the like having an alkenyl group, an aralkyl group, an aromatic group, or a heterocyclic group can be used.

Examples of the organic acid ester include carboxylic acid ester, sulfonic acid ester and phosphoric acid ester, and examples of the organic acid amide include carboxylic acid amide, sulfonic acid amide and phosphoric acid amide, and organic acid imide. As, carboxylic acid imide, sulfonic acid imide,
Examples thereof include phosphorimide. Of the organic acid esters, sulfonic acid esters are particularly effective. Specific preferred examples of the sulfonic acid ester include the following formulas (12) to
(16)

[Chemical 17]

Embedded image

[Chemical 19]

Embedded image

[Chemical 21] Partial sulfonic acid ester compounds of polyhydric phenols such as can be used. Such a sulfonic acid ester can be synthesized from a commercially available compound according to a conventional method.

These PAGs may be used alone or in combination of two or more. The blending amount of these PAGs is usually 0.01 part by weight, preferably 0.2 part by weight, with respect to 100 parts by weight of the resin used in the present invention.
The upper limit is usually 50 parts by weight, preferably 30 parts by weight.
If it is less than 0.01 parts by weight, it becomes impossible to form a pattern. If the amount exceeds 50 parts by weight, problems such as easy occurrence of undeveloped residue and deterioration of pattern shape occur, and in any case, it is not preferable in terms of resist performance.

In the present invention, the resist composition comprising the resin and PAG is used by dissolving it in a solvent. As the solvent, those generally used as a solvent for a resist composition can be used, and specific examples thereof include ketones such as acetone, methyl ethyl ketone, cyclohexanone and cyclopentanone; n-propanol, i-propanol, n. -Alcohols such as butanol, i-butanol, t-butanol, cyclohexanol; ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dioxane; ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol Alcohol ethers such as monoethyl ether; propyl formate, butyl formate, propyl acetate, butyl acetate, methyl propionate,
Esters such as ethyl propionate, methyl butyrate and ethyl butyrate; Oxycarboxylic acid esters such as methyl α-oxypropionate, ethyl α-oxypropionate, methyl 2-methoxypropionate and ethyl 2-methoxypropionate; cellosolve Cellosolve esters such as acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propyl cellosolve acetate, butyl cellosolve acetate; propylene glycols such as propylene glycol, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether; diethylene glycol Recall monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol Diethylene glycols such as dimethyl ether and diethylene glycol diethyl ether; halogenated hydrocarbons such as trichloroethylene; aromatic hydrocarbons such as toluene and xylene; N,
Examples thereof include polar solvents such as N-dimethylformamide, N, N-dimethylacetamide, N-methylacetamide, N-methylpyrrolidone, etc., which may be used alone or in combination with 2
You may use it in mixture of 2 or more types.

In the present invention, additives which are generally added to the resist composition as additives, for example, surfactants, storage stabilizers, sensitizers, antistriation agents, low molecular weight phenolic compounds and the like are compatible additives. Agents can be included.

In the composition of the present invention, the above formulas (1) to
The polymer having the structural unit represented by (3) undergoes the action of the acid generated from the acid generator upon irradiation with radiation, and the solubility of the irradiated portion changes. The composition of the present invention acts as a positive resist by using an alkaline developer. By allowing the structural unit represented by the formula (1) to exist in the polymer, dry etching resistance, resolution,
The resist characteristics such as the dissolution inhibiting effect are improved.

In the resist composition of the present invention, an alkaline aqueous solution is usually used as an alkaline developing solution. Specific examples thereof include aqueous solutions of inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium silicate, and ammonia; ethylamine, propyl. Aqueous solutions of primary amines such as amines;
Aqueous solutions of secondary amines such as diethylamine and dipropylamine; aqueous solutions of tertiary amines such as trimethylamine and triethylamine; aqueous solutions of alcohol amines such as diethylethanolamine and triethanolamine; tetramethylammonium hydroxide, tetraethylammonium hydroxide, Examples thereof include aqueous solutions of quaternary ammonium hydroxide such as trimethylhydroxymethylammonium hydroxide, triethylhydroxymethylammonium hydroxide and trimethylhydroxyethylammonium hydroxide. Further, if necessary, a water-soluble organic solvent such as methanol, ethanol, propanol, or ethylene glycol, a surfactant, a resin dissolution inhibitor, or the like can be added to the alkaline aqueous solution.

A resist film can be formed by applying a resist solution prepared by dissolving the resist composition of the present invention in a solvent onto the surface of a substrate such as a silicon wafer by a conventional method, and then removing the solvent by drying. As a coating method at this time, spin coating is particularly preferred. The exposure source used in the exposure for forming the pattern on the resist film thus obtained is deep ultraviolet ray, KrF
Excimer laser light, X-ray, electron beam and the like can be mentioned.
Furthermore, by performing a heat treatment (post-exposure bake) after exposure,
Terminate the deprotection reaction.

The preferred embodiments of the present invention are shown below. It is characterized by containing a polymer containing structural units represented by the general formulas (1), (2) and (3) and a radiation-sensitive component which produces an acid when irradiated with activating radiation. A resist composition, wherein A of R ⁴ in formula (1) is the above formula (6). It is characterized by containing a polymer containing structural units represented by the general formulas (1), (2) and (3) and a radiation-sensitive component which produces an acid when irradiated with activating radiation. In the resist composition, k, m, and n in the formulas (1) to (3) represent the proportions of the respective constituent units, and when the sum of the proportions of the respective constituent units in the polymer is 1, 0 <k < 0.9
5, 0 <m <0.95, 0.05 ≦ n ≦ 0.6, 0.1
≦ k / (k + m) <1, 0.4 ≦ (k + m) / (k + m
+ N) ≦ 0.95, a resist composition. It is characterized by containing a polymer containing structural units represented by the general formulas (1), (2) and (3) and a radiation-sensitive component which produces an acid when irradiated with activating radiation. In the resist composition, A of R ⁴ in the formula (1) is the formula (6), and k in the formulas (1) to (3),
m and n represent the proportions of the respective constituent units, and when the sum of the proportions of the respective constituent units in the polymer is 1, 0 <k <0.95,0
<M <0.95, 0.05 ≦ n ≦ 0.6, 0.1 ≦ k /
(K + m) <1, 0.4 ≦ (k + m) / (k + m + n)
A resist composition, wherein ≦ 0.95. It is characterized by containing a polymer containing structural units represented by the general formulas (1), (2) and (3) and a radiation-sensitive component which produces an acid when irradiated with activating radiation. In the resist composition, R ⁵ of the formula (3) is an unsubstituted substituted alkyl group at the 1-position or a group represented by the above formula (5). It is characterized by containing a polymer containing structural units represented by the general formulas (1), (2) and (3) and a radiation-sensitive component which produces an acid when irradiated with activating radiation. In the resist composition, k, m, and n in the formulas (1) to (3) represent the proportions of the respective constituent units, and when the sum of the proportions of the respective constituent units in the polymer is 1, 0 <k < 0.9
5, 0 <m <0.95, 0.05 ≦ n ≦ 0.6, 0.3
≦ k / (k + m) <1, and R ^{5 in the} formula (3) is 1
A resist composition, wherein the position is an unsubstituted alkyl group which can be substituted. It is characterized by containing a polymer containing structural units represented by the general formulas (1), (2) and (3) and a radiation-sensitive component which produces an acid when irradiated with activating radiation. In the resist composition, k, m, and n in the formulas (1) to (3) represent the proportions of the respective constituent units, and when the sum of the proportions of the respective constituent units in the polymer is 1, 0 <k < 0.9
5, 0 <m <0.95, 0.05 ≦ n ≦ 0.6, k /
(K + m) <0.3, and R ⁵ in formula (3) is a group represented by formula (5) above.

[0038]

EXAMPLES The present invention will be described in more detail below with reference to Reference Examples, Synthesis Examples and Examples. In addition, part and% in each example
Is weight basis unless otherwise specified.

Reference Example 1 3-Methyl-2-butenyl
Synthesis of Bromoacetate 3-Methyl-2-buten-1-ol (0.51mo
l), 51.6 g of triethylamine (0.51 mo
1) and 300 ml of dichloromethane were charged into a 1 liter flask and cooled to 0 ° C. While stirring this at 0 ° C., 100.9 g (0.50) of bromoacetyl bromide
(mol) was added dropwise over 1 hour, and stirring was continued at room temperature for 3 hours. The solid content was filtered from the obtained reaction solution, washed with water three times and then distilled to obtain 66.5 g of 3-methyl-2-butenyl bromoacetate.

Reference Example 2 1-Methyl-2-butenyl
Synthesis of bromoacetate 1-Methyl-butanol was prepared in the same manner as in Reference Example 1 except that 4-penten-2-ol (43.9 g, 0.51 mol) was used instead of 3-methyl-2-buten-1-ol. Two
-Butenyl bromoacetate was obtained.

(Synthesis Example 1) 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate polymer polymerization step 4-hydroxystyrene 72.1 g (0.60 mo)
1), 17.0 g of n-butyl methacrylate (0.1
2 mol), azobisisobutyronitrile 1.5 g
(0.009 mol), dioxane 150 ml 500
The mixture was placed in a ml flask and stirred under a nitrogen stream at 80 ° C. for 20 hours. The obtained reaction solution was poured into 5 liters of xylene, and the generated precipitate was filtered. The obtained solid content was dissolved in 200 ml of diethyl ether, poured into 3 liters of n-hexane, and the generated precipitate was filtered (reprecipitation operation). This reprecipitation operation was repeated 3 times and then dried,
3.6 g of 4-hydroxystyrene / n-butyl methacrylate polymer was obtained. As a result of GPC analysis, the obtained polymer was Mw = 5,600. Also, ¹ H-N
As a result of MR spectrum analysis, 4-hydroxystyrene /
Polymerization ratio of n-butyl methacrylate polymer is 68 /
It was 32.

Modification Step 4-hydroxystyrene / n-butyl obtained above
Methacrylate polymer 23.6g, acetone 150ml
Was charged into a 500 ml flask and dissolved. 7.7 g (0.037 mol) of 3-methyl-2-butenyl bromoacetate obtained in Reference Example 1, 6.9 g (0.05 mol) of anhydrous potassium carbonate, and 8.3 g of potassium iodide.
(0.05 mol) was added, and the mixture was stirred at 50 ° C. for 8 hours. After removing salts from the obtained reaction solution, the reaction solution was poured into 5 liters of n-hexane and the resulting precipitate was filtered. The obtained solid content was dissolved in 100 ml of diethyl ether, poured into 5 liters of hexane, and the generated precipitate was filtered (reprecipitation operation). After repeating this reprecipitation operation twice,
It was dried to obtain 28.3 g of 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate copolymer. The obtained polymer was analyzed by GPC and Mw =
It was 5,660. Moreover, as a result of ¹ H-NMR spectrum analysis, the ratio of 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate was 23/49.
It was / 28.

(Synthesis Example 2) 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / ethyl methacrylate polymer Polymerization step Ethyl methacrylate 13.7 g (0.12 mol)
21.9 g by the same operation as in Synthesis Example 1 except that
4-hydroxystyrene / ethyl methacrylate polymer was obtained. As a result of GPC analysis, the obtained polymer was M
It was w = 6,150. As a result of ¹ H-NMR spectrum analysis, the polymerization ratio of the 4-hydroxystyrene / ethyl methacrylate polymer was 71/29. Modification Step Synthesis Example 1 except that 21.9 g of the 4-hydroxystyrene / ethyl methacrylate polymer obtained above was used.
By the same operation as described above, 26.4 g of 4- (3-
Methyl-2-butenyloxycarbonylmethyloxy)
A styrene / 4-hydroxystyrene / ethyl methacrylate copolymer was obtained. As a result of GPC analysis, the obtained polymer was Mw = 6,150. Also, ¹ H-NM
As a result of R spectrum analysis, the ratio of 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / ethyl methacrylate was
It was 20/51/29.

(Synthesis Example 3) 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2-hydroxyethyl methacrylate polymer polymerization step 2-hydroxyethyl methacrylate 15.6 g
By the same procedure as in Synthesis Example 1 except that (0.12 mol) was used, 22.2 g of 2-hydroxyethyl methacrylate / 4-hydroxystyrene polymer was obtained. As a result of GPC analysis, the obtained polymer was Mw = 6,300. Moreover, as a result of ¹ H-NMR spectrum analysis, 4-
The polymerization ratio of the hydroxystyrene / 2-hydroxyethyl methacrylate polymer was 74/26. Modification step: 26.5 g of the 4-hydroxystyrene / 2-hydroxyethyl methacrylate polymer obtained above was used, and the same procedure as in Synthesis Example 1 was repeated to dry the product to 26.5 g.
g of 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2
-Hydroxyethyl methacrylate copolymer was obtained.
The obtained polymer was Mw = 6,35 as a result of GPC analysis.
It was 0. Moreover, as a result of ¹ H-NMR spectrum analysis, 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2
The ratio of hydroxyethyl methacrylate is 23 /
It was 52/25.

(Synthesis Example 4) 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate polymer Polymerization step 1-methylcyclohexyl methacrylate g21.8
25.9 g of 4-hydroxystyrene / 1-methylcyclohexyl methacrylate polymer was obtained by the same operation as in Synthesis Example 1 except that (0.12 mol) was used. As a result of GPC analysis, the obtained polymer had Mw of 6,450.
Met. In addition, as a result of ¹ H-NMR spectrum analysis,
4-hydroxystyrene / 1-methylcyclohexyl
The polymerization ratio of the methacrylate polymer was 77/23. Modification Step By the same procedure as in Synthesis Example 1 except that 25.9 g of the 4-hydroxystyrene / 1-methylcyclohexyl methacrylate polymer obtained above was used, the drying step was performed.
0.1 g of 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate copolymer was obtained. The obtained polymer has a Mw of GPC analysis.
= 6,450. As a result of ¹ H-NMR spectrum analysis, the ratio of 4- (3-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate was 23/52/25. It was

(Synthesis Example 5) 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate polymer 4-hydroxy obtained by the same operation as Synthesis Example 1 Other than using a styrene / n-butyl methacrylate polymer,
By the same operation as in Synthesis Example 1, drying was performed to obtain 28.0 g of 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate copolymer. As a result of GPC analysis, the obtained polymer was Mw = 5,800. As a result of ¹ H-NMR spectrum analysis, the polymerization ratio of 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / n-butyl methacrylate was 25/47/28. It was

(Synthesis Example 6) 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / ethyl methacrylate polymer 4-hydroxystyrene / obtained by the same procedure as in Synthesis Example 2 By the same operation as in Synthesis Example 2 except that the ethyl methacrylate polymer was used, 26.2 g of 4-
A (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / ethyl methacrylate copolymer was obtained. The obtained polymer is GP
As a result of C analysis, Mw was 6,160. Also, ¹ H
-As a result of NMR spectrum analysis, 4- (1-methyl-2)
-Butenyloxycarbonylmethyloxy) styrene /
The ratio of 4-hydroxystyrene / ethyl methacrylate was 29/44/27.

(Synthesis Example 7) 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2-hydroxyethyl methacrylate polymer 4-obtained by the same procedure as in Synthesis Example 3 Drying was performed in the same manner as in Synthesis Example 3 except that the hydroxystyrene / 2-hydroxyethyl methacrylate polymer was used.
5.8 g of 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2-hydroxyethyl methacrylate copolymer was obtained. The obtained polymer was analyzed by GPC and Mw =
It was 6,250. Moreover, as a result of ¹ H-NMR spectrum analysis, the ratio of 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 2-hydroxyethyl methacrylate was
It was 25/46/29.

(Synthesis Example 8) 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate polymer 4-obtained by the same procedure as in Synthesis Example 4 29.8 g of 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4 was dried by the same operation as in Synthesis Example 4, except that hydroxystyrene / 1-methylcyclohexyl methacrylate polymer was used. -Hydroxystyrene / 1-methylcyclohexyl methacrylate copolymer was obtained. As a result of GPC analysis, the obtained polymer was Mw = 6,350. As a result of ¹ H-NMR spectrum analysis, the polymerization ratio of 4- (1-methyl-2-butenyloxycarbonylmethyloxy) styrene / 4-hydroxystyrene / 1-methylcyclohexyl methacrylate was 24/50/26. there were.

(Examples 1 to 8 and Comparative Example 1) The above Synthesis Example 1
.About.8 and as a comparative example, t-butylacetate modified poly (4-vinylphenol) prepared according to the method of Example 1 described in JP-A-5-249673 (weight average molecular weight (Mw) = 6 by GPC analysis). 000) each, 100 parts each, triphenylsulfonium triflate 5 parts as an acid generator, and 0.01 parts of a fluorine-based surfactant are dissolved in 440 parts of ethyl lactate to obtain a 0.1 μm polytetrafluoroethylene filter (Japan Millipore (Made by the company)
To obtain a resist solution. This resist solution was spin-coated on a silicon wafer and then baked at 90 ° C. for 90 seconds to form a resist film having a thickness of 1.0 μm. This wafer was exposed using a KrF excimer stepper (NA = 0.45) and a test reticle. Then, after baking at 90 ° C. for 60 seconds, an immersion phenomenon with an aqueous solution of tetramethylammonium hydroxide was carried out for 1 minute to obtain a positive pattern.
The results are shown in Table 1.

[0051]

[Table 1]

From these results, it was found that the resin of the present invention can provide ideal sensitivity, high resolution and good pattern shape. Further, since the resin of the present invention has C = C derived from the substituted allyloxy group of the above formula (1), UV curing which is impossible with the conventional resin having an acid labile group having no unsaturated bond. It has been found that as a result, pattern sagging due to heat generated during etching is less likely to occur (etching resistance, heat resistance).

[0053]

As described above, according to the present invention, resist characteristics such as sensitivity, resolution, heat resistance, etching resistance, and pattern shape are excellent, and it is suitable for lithography using deep ultraviolet rays having a short wavelength or KrF excimer laser light. A resist material is obtained. The resist composition of the present invention is particularly suitable as a positive resist for fine processing of semiconductor devices.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasumasa Wada 1-2-1, Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa Japan Zeon Corporation

Claims (1)

[Claims] 1. General formulas (1), (2) and (3): Embedded image Embedded image (In the formulas (1) to (3), R ^{1 to} R ³ are each independently a hydrogen atom, a substituted alkyl group having 1 to 4 carbon atoms, a halogen atom, a cyano group or a nitro group, and R ⁴ is the following formula. (4) [Chemical 4] (In the formula (4), R ^{6 to} R ¹⁰ may be the same or different from each other, and a hydrogen atom, a halogen atom, a nitro group, a cyano group,
It is a substitutable alkyl group, a substitutable alkenyl group, a substitutable alkadienyl group or a substitutable vinyl group, and at least two of R ^{6 to} R ¹⁰ are substituents other than hydrogen atoms. R
⁶ and R ⁹ , R ⁸ and R ¹⁰ , and R ⁹ and R ¹⁰ may independently form a ring. Further, each of R ^{6 to} R ¹⁰ independently has 12 or less carbon atoms. A is a single bond or a divalent organic group. And R ⁵ is a linear, branched or cyclic, substitutable alkyl group or the following formula (5) (In the formula (5), R ¹¹ is a substitutable alkyl group or a substitutable alkenyl group, R ^{12 to} R ¹⁵ are hydrogen atoms, halogen atoms or substitutable alkyl groups, and at least one of R ^{12 to} R ¹⁵ is selected. Is a hydrogen atom, and B is a divalent organic group.). In the formulas (1) to (3), k, m, and n represent the proportions of the respective constituent units, and when the sum of the proportions of the respective constituent units in the polymer is 1, 0 <k <0.95,0. <M <0.9
5, 0.05 ≦ n ≦ 0.6, 0.1 ≦ k / (k + m) <
It is 1. ) A resist composition comprising a polymer having a structural unit represented by the formula (1) and a radiation-sensitive component which produces an acid when exposed to activating radiation.