JP2001147523A - Positive resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive resist composition, in which the problems of the performance improvement technique of a microphoto application of its own using far ultraviolet ray, particularly ArF excimer laser beam are solved and concretely, the improvement of sensitivity and resolution and a problem of generating particles in a resist solution with the lapse of time are resolved. SOLUTION: The positive resist composition contains an acid generating agent by light having a specific structure which generates an acid by the irradiation with active light or radiation and a polymer having a repeating structural unit of a specific structure, a repeating structural unit of a specific structure having an alicyclic ring in the main chain and a group decomposing by the action of the acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive resist composition capable of using far ultraviolet rays as an exposure light source for an ultra microlithography process such as the production of an ultra LSI and a high capacity microchip and other photofabrication processes. From a different point of view, the present invention relates to a positive resist composition capable of forming a high-definition pattern by using light having a wavelength of 220 nm or less, particularly a deep ultraviolet region including excimer laser light.

[0002]

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

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

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

JP-A-10-10739 discloses an energy-sensitive resist containing a polymer obtained by polymerizing a monomer having an alicyclic structure such as a norbornene ring in its main chain, maleic anhydride, and a monomer having a carboxyl group. Materials are disclosed. JP-A-10-111569 and JP-A-11-202491 disclose radiation-sensitive resin compositions containing a resin having an alicyclic skeleton in the main chain and a radiation-sensitive acid generator. .

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

[0007] That is, the resist composition is prepared as a solution to be applied to a substrate. However, as the solution elapses, so-called fine particles are generated with the passage of time, and there is a problem of storage stability that the resist composition cannot be used. Was.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the problem of the performance improvement technology inherent in microphotofabrication using far ultraviolet light, particularly ArF excimer laser light. More specifically, it is an object of the present invention to provide a positive resist composition which is excellent in sensitivity and resolution and which solves the problem that particles are generated in a resist solution over time.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies on the constituent materials of a resist composition in a positive-type chemical amplification system, and have found that a specific photoacid generator and a specific acid-decomposable resin are used. It was found that the object of the present invention was achieved, and the present invention was achieved. That is, the above object is achieved by the following constitutions.

(1) (A) at least one compound selected from the compounds represented by the following general formulas (I) and (II) which generate an acid upon irradiation with actinic rays or radiation; It has at least one of the repeating structural units represented by the general formulas (Ia ′) and (Ib ′) and the repeating structural unit represented by the following general formula (II ′), and is decomposed by the action of an acid. A positive resist composition comprising a polymer having a group represented by the formula:

[0011]

Embedded image

In the above general formulas (I) to (II): R _{1 to} R ₂₇
Each independently represents a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group, a halogen atom, or an -S-R ₂₈ group. R ₂₈ represents a linear, branched or cyclic alkyl group or aryl group. However, R _{1 to} R ₁₅ , R _{16 to} R
_At least one of ₂₇ is not a hydrogen atom. Also,
Two or more of R _{1 to} R ₁₅ and R _{16 to} R ₂₇ are bonded,
It may form a ring containing one or more selected from a single bond, carbon, oxygen, sulfur and nitrogen. X ^-
Represents R ^F SO ₃ ^— . Here, R ^F is a fluorine-substituted linear, branched or cyclic alkyl group having 2 or more carbon atoms.

[0013]

Embedded image

In the formula (Ia ′), R ′ ₁ and R ′ ₂ each independently represent a hydrogen atom, a cyano group, a hydroxyl group, —COOH, —CO
_{OR '5, -CO-NH-} R' 6, -CO-NH-SO 2 -
R ′ _{6 represents} an optionally substituted alkyl group, an optionally substituted alkoxy group or an optionally substituted cyclic hydrocarbon group, or the following —Y group. Where R '
₅ represents an alkyl group which may have a substituent, a cyclic hydrocarbon group which may have a substituent, or the following -Y group. R ′ ₆ represents an alkyl group which may have a substituent or a cyclic hydrocarbon group which may have a substituent. X
It represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-. A represents a single bond or a divalent linking group. -Y group:

[0015]

Embedded image

(In the —Y group, R ′ _{21 to} R ′ ₃₀ each independently represent a hydrogen atom or an alkyl group which may have a substituent. A and b are 1 or 2.) In (Ib ′): Z ₂ represents —O— or —N (R ′ ₃ ) —. Here, R ′ ₃ is a hydrogen atom, a hydroxyl group or —OSO ₂
-R 'represents a _4. R ₄ ′ represents an alkyl group, a haloalkyl group, a cycloalkyl group or a camphor residue. In the formula (II ′), R ′ ₁₁ and R ′ ₁₂ each independently represent a hydrogen atom, a cyano group, a halogen atom, or an alkyl group which may have a substituent. Z represents an atomic group containing two bonded carbon atoms (C-C) and forming an alicyclic structure which may have a substituent. (2) The repeating structural unit represented by the general formula (II ') is a repeating structural unit represented by the following general formula (II'-A) or (II'-B). The positive resist composition according to (1) above.

[0017]

Embedded image

In the general formulas (II'-A) and (II'-B): R '
_{13 to} R ′ ₁₆ each independently represent a hydrogen atom, a halogen atom,
A cyano group, -COOH, -COOR '(the ₅ R' ₅ are as defined above), it is decomposed by the action of an acid group, -C (= O)
—XAR ′ ₁₇ , or an alkyl group or a cyclic hydrocarbon group which may have a substituent. Also, R ' _l3 ~
At least two may be combined with each other to form a ring of R _'16. Here, X and A have the same meanings as above. R ′ ₁₇ represents —COOH, —COOR ′ ₅ , —CN, a hydroxyl group, an optionally substituted alkoxy group, —CO
_{-NH-R '6, -CO-} NH-SO 2 -R' 6 (R '5, R'
₆ is the same as defined above), or represents the above -Y group. n is 0 or 1. (3) X in the general formula (I) and (II) ^- the R ^F is C
F ₃ (CF ₂₎ y (where, y is a is 1-9 integer) positive according to (1) or (2), characterized in that a fluorine-substituted linear alkyl group represented by -Type resist composition. (4) The positive resist composition according to (3), wherein y is an integer of 1 to 7. (5) The positive resist composition according to the above (4), wherein y is an integer of 1 to 4. (6) The positive resist composition as described in any of (1) to (5) above, wherein the component (A) is a compound having the following structure.

[0019]

Embedded image

X ^- has the same meaning as described above. (7) The positive resist composition according to any one of (1) to (6), further comprising a nitrogen-containing basic compound. (8) The positive resist composition according to any one of (1) to (7), further comprising a fluorine-based and / or silicon-based surfactant. (9) The positive resist composition as described in any one of (1) to (8) above, which is used for irradiation with actinic rays or radiation having a wavelength of 220 nm or less.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the compounds used in the positive resist composition of the present invention and the method of using the composition will be described in detail. [1] (A) Compound that generates an acid upon irradiation with actinic rays or radiation (photoacid generator) In the present invention, as the photoacid generator, the compound represented by the above general formula (I) or (II) is used. At least one is used. In the general formulas (I) to (II), R _{1 to} R ₂₇ and R ₂₈
Examples of the linear or branched alkyl group having 1 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group and a t-butyl group which may have a substituent.
To four. As the cyclic alkyl group,
What has a C3-C8 group which may have a substituent, such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group, is mentioned. Examples of the linear or branched alkoxy group represented by R _{1 to} R ₂₇ include a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group and a t-butoxy group. Such a C1-C4 thing is mentioned. Examples of the cyclic alkoxy group include a cyclopentyloxy group, for example, a cyclopentyloxy group and a cyclohexyloxy group. Examples of the halogen atom for R _{1 to} R ₂₇ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the aryl group for R ₂₈ include a phenyl group,
Those having 6 to 14 carbon atoms which may have a substituent such as a tolyl group, a methoxyphenyl group and a naphthyl group are exemplified. These further substituents are preferably those having 1 carbon atom.
~ 4 alkoxy groups, halogen atoms (fluorine atom, chlorine atom, iodine atom), aryl groups having 6 to 10 carbon atoms,
Examples thereof include an alkenyl group having 2 to 6 carbon atoms, a cyano group, a hydroxy group, a carboxy group, an alkoxycarbonyl group, and a nitro group.

Examples of the ring formed by combining two or more of R _{1 to} R ₁₅ and containing one or more selected from a single bond, carbon, oxygen, sulfur, and nitrogen include, for example, , A furan ring, a dihydrofuran ring, a pyran ring, a trihydropyran ring, a thiophene ring, a pyrrole ring and the like. The same applies to R _{16 to} R ₂₇ .

In the general formulas (I) and (II), X
^-Is R^FSO_Three ^-Is an anion represented by Where R^F
Has 2 or more carbon atoms, preferably 2 to 10 carbon atoms,
Preferably it has 2 to 8 carbon atoms, more preferably 2 to 5 carbon atoms.
Fluorine-substituted linear, branched or cyclic alkyl
Group. Preferred R^FAs CF_Three(CF_Two) y
Wherein y is an integer of 1 to 9;
A kill group, more preferably y is an integer of 1 to 7,
Preferably, y is an integer of 1 to 4
It is a kill group. These fluorine-substituted linear alkyl groups
[CF_Three(CF_Two) y], sensitivity and resolution
Excellent balance between exposure and post-heating.
However, the performance change is small. R^FAs a specific
Is CF_ThreeCF_Two-, CF_Three(CF_Two)_Two-, CF_Three(C
F_Two)_Three-, CF_Three(CF_Two)_Four-, CF_Three(CF_Two)_Five-, C
F_Three(CF_Two)₆-, CF_Three(CF_Two)₇-, CF_Three(CF_Two)
₈-, CF_Three(CF_Two)₉-Is preferred, and more preferred.
Or CF_Three(CF_Two)_Three-, CF_Three(CF_Two)₇-
Most preferably CF _Three(CF_Two)_Three-.

Particularly preferred photoacid generators are those of the general formula (I)
And a compound in which each benzene ring of the cation moiety is substituted with a t-butyl group, and particularly preferably a compound wherein X ⁻ is CF ₃ (CF ₂ ) ₃ SO ₃ ^— .

The compounds represented by the general formulas (I) and (II) in which such an anion portion is composed of a sulfonate anion having a fluorine-substituted alkyl group are used as a photoacid generator and will be described later. When combined with the acid-decomposable resin component (A) having a specific structure, the positive resist composition of the present invention has sufficient sensitivity and resolution to exposure to far ultraviolet light, particularly ArF excimer laser light (wavelength 193 nm). Moreover, no particles are generated even if the resist solution prepared for coating is stored for a long period of time.

Specific examples of the photoacid generators represented by formulas (I) and (II) include the following compounds (I-1) to (I-2)
7) and (II-1) to (II-7).

[0027]

Embedded image

[0028]

Embedded image

[0029]

Embedded image

[0030]

Embedded image

[0031]

Embedded image

The amount of the photoacid generator (B) represented by the above general formulas (I) and (II) is usually in the range of 0.001 to 40% by weight based on the solids in the composition. It is preferably used in the range of 0.01 to 20% by weight, more preferably 0.1 to 5% by weight. When the addition amount of the photoacid generator is less than 0.001% by weight, the sensitivity is lowered. When the addition amount is more than 40% by weight, the light absorption of the resist becomes too high, and the deterioration of the profile and the process (particularly baking) ) The margin is undesirably narrow.

In the positive resist composition of the present invention, a photoacid generator other than the compounds represented by formulas (I) and (II) can be used in combination. Known photoacid generators that can be used in combination include photoinitiators for photocationic polymerization, photoinitiators for photoradical polymerization, photodecolorants for dyes, photochromic agents, and microresists. Light (4
Ultraviolet rays of from 200 to 200 nm, far ultraviolet rays, particularly preferably g-line, h-line, i-line, KrF excimer laser light),
A compound capable of generating an acid by an ArF excimer laser beam, an electron beam, an X-ray, a molecular beam or an ion beam, and a mixture thereof can be appropriately selected and used.

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

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

Among the compounds capable of decomposing upon irradiation with actinic rays or radiation to generate an acid, the compounds represented by the following general formulas (PAG3) and (PAG) are particularly effective.
4) and a compound represented by the general formula (PAG6) or the general formula (PAG7).

[0037]

Embedded image

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

[0039] Z ^- represents a counter anion, for example BF ₄ ^{-,
_{AsF 6 -, PF 6 -,}} SbF 6 -, SiF 6 2-, ClO 4 -,
Alkanesulfonic acid which may be substituted, perfluoroalkanesulfonic acid, benzenesulfonic acid which may be substituted, naphthalenesulfonic acid, anthracenesulfonic acid,
Examples include but are not limited to camphor sulfonic acid. Preferred are alkanesulfonic acid, perfluoroalkanesulfonic acid, alkyl-substituted benzenesulfonic acid, and pentafluorobenzenesulfonic acid. Two of R ²⁰³ , R ²⁰⁴ , and R ²⁰⁵ and Ar ¹ , Ar ²
May be bonded via each single bond or a substituent.

In the general formulas (PAG6) and (PAG7), R
²⁰⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, or arylene group. R represents a linear, branched or cyclic alkyl group, or an optionally substituted aryl group. Specific examples thereof include the following compounds, but are not limited thereto.

[0041]

Embedded image

[0042]

Embedded image

These photoacid generators that can be used in combination are used in an amount of 5% by weight or less, preferably 2% by weight or less, based on the solid content in the composition.

[2] (B) At least one of the repeating structural units represented by the general formulas (Ia ') and (Ib') and the repeating structural unit represented by the general formula (II ') And a polymer having a group that is decomposed by the action of an acid (hereinafter, abbreviated as “resin according to the present invention”)

In the above formula (Ia ′), R ′ ₁ , R ′
₂ is each independently a hydrogen atom, a cyano group, a hydroxyl group, -C
_{OOH, -COOR '5, -CO-} NH-R' 6, -CO
—NH—SO ₂ —R ′ _{6 represents} an alkyl group which may be substituted, an alkoxy group which may be substituted or a cyclic hydrocarbon group which may be substituted, or the above-mentioned —Y group. Here, R _'5 is an optionally substituted alkyl group, or cyclic optionally substituted hydrocarbon group or the -Y group. R ′ ₆ represents an alkyl group which may have a substituent or a cyclic hydrocarbon group which may have a substituent. In the -Y group, R _'21 ~R' ₃₀ each independently represent a hydrogen atom or an optionally substituted alkyl group, a, b is 1 or 2. X represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or -NHSO ₂ N
Represents H-. A represents a single bond or a divalent linking group.

In the formula (Ib ′), Z ₂ represents —O— or —N (R ′ ₃ ) —. Wherein R _'3 is a hydrogen atom, a hydroxyl group or -OSO ₂ -R' represents a _4. R ′ ₄ is an alkyl group,
Represents a haloalkyl group, a cycloalkyl group or a camphor residue.

[0047] The _{R '1, R' 2,} R '4, R' 5, R '6,
As the alkyl group for R ′ _{21 to} R ′ ₃₀ ,
Preferred are 10 linear or branched alkyl groups,
More preferably, it is a linear or branched alkyl group having 1 to 6 carbon atoms, and still more preferably, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-group. -A butyl group. As the _{R '1, R' 2,} R cyclic hydrocarbon group in _'5, R' _6, a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, 2-methyl-2-adamantyl group, norbornyl group, bornyl Group, isobornyl group, tricyclodecanyl group, dicyclopentenyl group,
Nobornane epoxy group, menthyl group, isomenthyl group,
Examples include a neomenthyl group and a tetracyclododecanyl group. Examples of the alkoxy group in R ′ ₁ and R ′ ₂ include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. The haloalkyl group represented by R _'4 can be exemplified trifluoromethyl, nano-fluoro butyl group, pentadecafluorooctyl group, a trichloromethyl group and the like. The cycloalkyl groups represented by R _'4, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.

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

The divalent linking group of A in the above formulas (Ia ′) and (Ib ′) includes an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, and a sulfonamide. A single group selected from the group consisting of a group, a urethane group and a urea group, or a combination of two or more groups. Examples of the alkylene group and substituted alkylene group in A include groups represented by the following formula. -[C (R _a ) (R _b )] _r-wherein R _a and R _b represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group,
Both may be the same or different. As the alkyl group, a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group is preferable, and a methyl group, an ethyl group, a propyl group, and an isopropyl group are more preferable. As the substituent of the substituted alkyl group,
Examples include a hydroxyl group, a halogen atom and an alkoxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r represents an integer of 1 to 10.

Specific examples of the repeating structural unit represented by the general formula (Ia ') include the following [I-1] to [I-65].
However, the present invention is not limited to these specific examples.

[0051]

Embedded image

[0052]

Embedded image

[0053]

Embedded image

[0054]

Embedded image

[0055]

Embedded image

[0056]

Embedded image

Specific examples of the repeating structural unit represented by the above general formula (Ib ') include the following [I'-1] to [I'-7].
However, the present invention is not limited to these specific examples.

[0058]

Embedded image

[0059]

Embedded image

In the general formula (II ′), R ′ ₁₁ , R ′
Each ₁₂ independently represents a hydrogen atom, a cyano group, a halogen atom, or an alkyl group which may have a substituent.
Z represents an atomic group containing two bonded carbon atoms (C-C) and forming an alicyclic structure which may have a substituent.

Examples of the halogen atom in R ′ ₁₁ and R ′ ₁₂ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. The alkyl group for R ′ ₁₁ and R ′ ₁₂ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably 1 to 10 carbon atoms.
It is six linear or branched alkyl groups, more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group.

Further substituents on the alkyl groups of R ′ ₁₁ and R ′ ₁₂ include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group, an acyloxy group and the like. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom and an iodine atom, and examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group, and examples of the acyloxy group include an acetoxy group.

The atomic group for forming the alicyclic structure of Z is an atomic group for forming a repeating structural unit of an alicyclic hydrocarbon which may have a substituent on the resin. An atomic group for forming a bridged alicyclic structure forming a repeating structural unit of an alicyclic hydrocarbon of the formula is preferred. Examples of the skeleton of the formed alicyclic hydrocarbon include those represented by the following structures.

[0064]

Embedded image

[0065]

Embedded image

Preferred bridged alicyclic hydrocarbon skeletons include (5), (6), (7),
(9), (10), (13), (14), (15),
(23), (28), (36), (37), (42),
(47).

The alicyclic hydrocarbon skeleton has a substituent.
It may be. As such a substituent, the above general
R ′ in formula (II′-A) or (II′-B)₁₃~ R '₁₆To
Can be mentioned. Contains the above bridged alicyclic hydrocarbon
Among the repeating structural units represented by the general formula (II′-
A) or a repeating structural unit represented by (II'-B)
Is more preferred. Formula (II′-A) or (II ′)
In -B), R ′₁₃~ R '₁₆Are each independently a hydrogen source
, Halogen atom, cyano group, -COOH, -COO
R '_Five(R ' _FiveIs an alkyl group which may have a substituent,
A cyclic hydrocarbon group which may have a substituent or
A group decomposed by the action of an acid, -C
(= O) -XA-R '₁₇Or even if it has a substituent
It represents a good alkyl group or a cyclic hydrocarbon group. n is 0
Or represents 1. X is an oxygen atom, a sulfur atom, -NH-,
-NHSO_Two-Or-NHSO_TwoRepresents NH-. R '₁₇
Is -COOH, -COOR '_Five, -CN, hydroxyl group, position
An alkoxy group which may have a substituent, -CO-NH-
R '₆, -CO-NH-SO_Two-R '₆(R '_Five, R '₆Is
As defined above) or a -Y group of the above general formula (Ia ')
Represents A represents a single bond or a divalent linking group.

In the resin according to the present invention, the acid-decomposable group includes the above-mentioned —C (上 記 O) -XA-R ′ ₁ , —C (＝ O)
—X—A—R ′ ₂ or a compound represented by the general formula (II ′)
May be included as a substituent of Z. The structure of the acid-decomposable group is represented by —C (＝ O) —X ₁ —R ₀ . In the formula, R ₀ represents 3 such as t-butyl group and t-amyl group.
Primary alkyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-alkoxyethyl group such as 1-cyclohexyloxyethyl group, 1-methoxymethyl group, 1-ethoxymethyl Alkoxymethyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3-oxocyclohexyl ester group, 2-methyl-2-adamantyl group, mevalonic lactone residue, 2- (γ- Butyrolactonyloxycarbonyl)-
Examples thereof include a 2-propyl group. X ₁ has the same meaning as X described above.

Examples of the halogen atom in R ′ _{13 to} R ′ ₁₆ include a chlorine atom, a bromine atom, a fluorine atom and an iodine atom.

The alkyl group for R ′ _{13 to} R ′ ₁₆ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. Alkyl group, more preferably methyl group, ethyl group, propyl group, isopropyl group, n-
A butyl group, an isobutyl group, a sec-butyl group and a t-butyl group.

Examples of the cyclic hydrocarbon group for R ′ _{13 to} R ′ ₁₆ include a cyclic alkyl group and a bridged hydrocarbon, and include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group and a 2-methyl-2 group. -Adamantyl group, norbornyl group, boronyl group, isobornyl group,
Examples include a tricyclodecanyl group, a dicyclopentenyl group, a nobornane epoxy group, a menthyl group, an isomenthyl group, a neomenthyl group, and a tetracyclododecanyl group. The ring formed by combining at least two of the above R ′ _{13 to} R ′ ₁₆ is preferably a ring having 5 to 5 carbon atoms such as cyclopentene, cyclohexene, cycloheptane and cyclooctane.
Twelve rings.

[0072] The alkoxy group in the above R _'17, a methoxy group, an ethoxy group, a propoxy group, may be mentioned those having 1 to 4 carbon atoms or a butoxy group.

Further substituents on the alkyl group, cyclic hydrocarbon group and alkoxy group include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group and an acyloxy group. As the halogen atom, a chlorine atom, a bromine atom, a fluorine atom,
And iodine atoms. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group. Examples thereof include an acetoxy group.

Examples of the divalent linking group represented by A include a single bond, an alkylene group, a substituted alkylene group, an ether group, a thioether group, and a carbonyl group, similarly to the divalent linking group represented by A in formula (Ia '). Group, ester group, amide group,
A single one selected from the group consisting of a sulfonamide group, a urethane group, and a urea group, or a combination of two or more groups is exemplified. Examples of the alkylene group and substituted alkylene group in A include those similar to the divalent linking group of A in formula (Ia ′).

In the resin according to the present invention, the group decomposed by the action of an acid is a repeating structural unit represented by the general formula (Ia ′), a repeating structural unit represented by the general formula (Ib ′), It can be contained in at least one of the repeating structural units represented by (II ′) and the repeating structural units of the copolymer component described below.

The formula (II'-A) or the formula (I
The various substituents R _'13 ~R' ₁₆ in I'-B) is for forming an atomic group to bridged alicyclic structure to form an alicyclic structure in formula (II) It is also a substituent of the atomic group Z.

The above general formula (II'-A) or general formula (I
Specific examples of the repeating structural unit represented by I′-B) include the following [II-1] to [II-166], but the present invention is not limited to these specific examples.

[0078]

Embedded image

[0079]

Embedded image

[0080]

Embedded image

[0081]

Embedded image

[0082]

Embedded image

[0083]

Embedded image

[0084]

Embedded image

[0085]

Embedded image

[0086]

Embedded image

[0087]

Embedded image

[0088]

Embedded image

[0089]

Embedded image

[0090]

Embedded image

[0091]

Embedded image

[0092]

Embedded image

[0093]

Embedded image

[0094]

Embedded image

The resin according to the present invention includes at least one of the structural units represented by the general formulas (Ia ′) and (Ib ′) and the general formula (II ′) (the general formula (II) '-A) and a repeating structural unit represented by the general formula (II'-B)), in addition to containing one or more of each, a dry etching resistance, a suitability for a standard developer,
For the purpose of adjusting the substrate adhesion, the resist profile, and the resolution, heat resistance, sensitivity, and the like, which are general requirements of the resist, a copolymer containing repeating structural units of various monomers can be used. Preferred copolymerization components include repeating structural units represented by the following general formulas (IV ') and (V').

[0096]

Embedded image

Where Z is an oxygen atom, -NH-,-
N (-R '₅₀)-, -N (-OSO_Two R '₅₀)-
R '₅₀Is also the same as the above (substituted) alkyl group, (substituted) ring
Hydrocarbon groups have meaning. The general formula (IV ′),
Specific examples of the repeating structural unit represented by (V ′) are as follows:
[IV'-9] to [IV'-16], [V'-9] to [V'-
16], but are not limited to these specific examples.
Not.

[0098]

Embedded image

[0099]

Embedded image

In the resin according to the present invention, as long as the effects of the present invention can be effectively obtained, the following monomers may be further copolymerized to give a repeating structural unit constituting the resin. Good, but not limited to the following monomers. Thereby, the performance required for the resin, particularly (1) solubility in a coating solvent, (2) film forming property (glass transition point), (3) alkali developability, and (4) film loss (hydrophobicity, alkali (Selection of a soluble group), (5) adhesion of the unexposed portion to the substrate, and (6) fine adjustment of dry etching resistance and the like can be performed. Examples of such a comonomer include acrylates, methacrylates,
Examples thereof include compounds having one addition-polymerizable unsaturated bond selected from acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and the like.

Specifically, for example, acrylates such as alkyl (the alkyl group has 1 to 1 carbon atoms)
Acrylates (for example, methyl acrylate, ethyl acrylate, propyl acrylate, amyl acrylate, cyclohexyl acrylate, ethylhexyl acrylate, octyl acrylate, acrylate-
t-octyl, chloroethyl acrylate, 2-hydroxyethyl acrylate 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate, Tetrahydrofurfuryl acrylate, etc.);

Methacrylic acid esters, for example, alkyl (alkyl having preferably 1 to 10 carbon atoms) methacrylate (for example, methyl methacrylate,
Ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate,
Benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate,
5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, etc.);

Acrylamides, for example, acrylamide, N-alkylacrylamide, (alkyl having 1 to 10 carbon atoms, for example, methyl, ethyl, propyl, butyl, t-butyl, heptyl, octyl Group, cyclohexyl group, hydroxyethyl group, etc.), N, N-dialkylacrylamide (alkyl group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, butyl group, isobutyl group, ethylhexyl group, Cyclohexyl group, etc.), N-
Hydroxyethyl-N-methylacrylamide, N-2
-Acetamidoethyl-N-acetylacrylamide and the like;

Methacrylamides, for example, methacrylamide, N-alkyl methacrylamide (alkyl having 1 to 10 carbon atoms, for example, methyl, ethyl, t-butyl, ethylhexyl, hydroxyethyl, cyclohexyl) Groups, etc.), N, N-dialkylmethacrylamide (an alkyl group includes an ethyl group, a propyl group, a butyl group, etc.), N-hydroxyethyl-N-methylmethacrylamide and the like;

Allyl compounds such as allyl esters (eg, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, etc.), allyloxy Ethanol, etc .;

Vinyl ethers such as alkyl vinyl ethers (eg, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2-ethyl Butyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether, etc.);

Vinyl esters such as vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxy acetate, vinyl butoxy acetate, Vinyl acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinylcyclohexylcarboxylate and the like;

Dialkyl itaconates (eg, dimethyl itaconate, diethyl itaconate, dibutyl itaconate, etc.); acrylic acid, methacrylic acid, crotonic acid, itaconic acid, acrylonitrile, methacrylonitrile and the like.

In the resin according to the present invention, the compound represented by the general formula (I)
a ′) and / or a repeating structural unit represented by the general formula (Ib ′) and a general formula (II ′) (including the general formulas (II′-A) and (II′-B)) Content of the repeating structural unit to be performed, the dry etching resistance of the desired resist,
It can be appropriately set in consideration of sensitivity, prevention of pattern cracking, substrate adhesion, resist profile, and resolution, heat resistance and the like, which are necessary requirements of general resists. Generally, the content of the repeating structural unit represented by the general formula (Ia ') and / or the general formula (Ib') and the repeating structural unit represented by the general formula (II ') in the resin according to the present invention. Is suitably at least 25 mol% in all monomer repeating structural units of the resin, and preferably 3 mol% or more.
It is at least 0 mol%, more preferably at least 35 mol%.

Further, in the resin according to the present invention, the content of the repeating structural unit (general formula (IV ′) or general formula (V ′)) derived from the above-mentioned preferable comonomer is not limited. Can be appropriately set in accordance with the performance of the dist. In general, the repeating unit represented by the general formula (Ia ′) and / or the general formula (Ib ′) and the general formula (II ′) It is preferably at most 99 mol%, more preferably at most 90 mol%, further preferably at most 80 mol%, based on the total number of moles of the repeating structural units to be obtained. Further, the content of the repeating structural unit based on the monomer of the further copolymerization component in the resin can be appropriately set according to the desired dist performance, but generally, the general formula (Ia ′) ) And / or 99 mol% or less, and more preferably, the total number of moles of the repeating structural unit represented by the general formula (Ib ′) and the repeating structural unit represented by the general formula (II ′). It is 90 mol% or less, more preferably 80 mol% or less. If the amount of the repeating structural unit based on the monomer of the further copolymer component exceeds 99 mol%, the effect of the present invention is not sufficiently exhibited, which is not preferable.

In the resin according to the present invention, the group decomposed by the action of an acid may be a repeating structural unit represented by the general formula (Ia ′) and / or the general formula (Ib ′) or a compound represented by the general formula (II ′) The repeating structural unit represented by) or the repeating structural unit based on the monomer of the copolymerization component may be contained, but the repeating structural unit containing a group decomposed by the action of an acid may be contained. The amount is suitably from 8 to 60 mol%, preferably from 10 to 55 mol%, more preferably from 12 to 50 mol%, based on all repeating structural units of the resin.
It is.

The resin according to the present invention comprises a monomer corresponding to the repeating structural unit represented by the general formula (II ') and maleic anhydride, and when a copolymerization component is used, a monomer of the copolymerization component. Are copolymerized in the presence of a polymerization catalyst, and the repeating structural units derived from maleic anhydride of the obtained copolymer are subjected to ring-opening esterification with alcohols under basic or acidic conditions, or It can also be synthesized by a method of decomposing and then converting the carboxylic acid moiety generated to a desired substituent.

The weight average molecular weight of the resin according to the present invention is G
It is preferably from 1,000 to 200,000 in terms of polystyrene according to the PC method. When the weight average molecular weight is less than 1,000, heat resistance and dry etching resistance are deteriorated, so that it is not preferable. When the weight average molecular weight exceeds 200,000, the developability is deteriorated and the viscosity becomes extremely high, so that the film forming property is deteriorated. And so on, which produces very unfavorable results.

In the positive photoresist composition for exposure to far ultraviolet rays according to the present invention, the amount of the resin according to the present invention in the entire composition is preferably 40 to 99.99% by weight, and more preferably the total solid content of the resist. Is 50 to 99.97% by weight.

[3] Fluorine and / or Silicon Surfactant The positive resist composition of the present invention preferably contains a fluorine and / or silicon surfactant. Examples of the fluorine-based and / or silicon-based surfactant include a fluorine-based surfactant, a silicon-based surfactant, and at least one type of surfactant containing both a fluorine atom and a silicon atom. When the positive resist composition of the present invention contains the above surfactant, the sensitivity, when using an exposure light source of 250 nm or less, particularly 220 nm or less,
A resist pattern with excellent resolution, substrate adhesion, and dry etching resistance, less generation of particles after storage over time, and less development defects and scum can be obtained. As these surfactants, for example, JP-A-62-36663, JP-A-61-36663
-226746, JP-A-61-226745, JP-A-62-170950,
JP-A-63-34540, JP-A-7-230165, JP-A-8-62834
, JP-A-9-54432 and JP-A-9-5988, and the following commercially available surfactants can be used as they are. As commercially available surfactants that can be used, for example, F-top EF301, EF303, (Shin-Akita Kasei
Co., Ltd.), Florado FC430, 431 (Sumitomo 3M Limited)
), Megafac F171, F173, F176, F189, R08 (Dai Nippon Ink Co., Ltd.), Surflon S-382, SC101, 102,
Fluorinated surfactants such as 103, 104, 105, and 106 (manufactured by Asahi Glass Co., Ltd.) and silicon-based surfactants can be exemplified. Also, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used as a silicon-based surfactant.

The amount of the surfactant is usually 0.001% by weight to 2% by weight based on the solid content in the composition of the present invention.
% By weight, preferably 0.01% to 1% by weight.
These surfactants can be used alone or in combination of two or more.

Examples of the other surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; Polyoxyethylene alkyl allyl ethers such as oxyethylene octyl phenol ether, polyoxyethylene nonyl phenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate Fatty acid esters such as sorbitan trioleate, sorbitan tristearate, polyoxyethylene sorbitan monolaurate Nonionic surfactants such as polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan tristearate, etc. Can be mentioned. The amount of these surfactants is usually 2 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the solids in the composition of the present invention. These surfactants may be added alone or in some combination.

[4] Organic Basic Compound A preferable organic basic compound that can be used in the present invention is a compound that is more basic than phenol. Among them, a nitrogen-containing basic compound having a structure represented by the following (A) to (E) is preferable. By using the nitrogen-containing basic compound, the performance change is small even with the lapse of time from exposure to post-heating.

[0119]

Embedded image

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

[0121]

Embedded image

Wherein R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶
Is the same or different and represents an alkyl group having 1 to 6 carbon atoms). Preferred specific examples include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazol, substituted or unsubstituted Pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted amino Examples include morpholine, substituted or unsubstituted aminoalkyl morpholine, and the like, and include mono, di, trialkylamine, substituted or unsubstituted aniline, substituted or unsubstituted piperidine, mono and diethanolamine, and the like. Preferred substituents are an amino group, aminoalkyl group, alkylamino group, aminoaryl group, arylamino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxyl group, cyano group It is.

Preferred compounds are guanidine, 1,
1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6
-Methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-
Aminoethyl) piperidine, 4-amino-2,2,6,
6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl)
Pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine ,
4,6-dihydroxypyrimidine, 2-pyrazoline, 3
-Pyrazolin, N-aminomorpholine, N- (2-aminoethyl) morpholine, 1,5-diazabicyclo [4,3,0] non-5-ene, 1,8-diazabicyclo [5,4,0] Undec-7-ene, 2,4,5-triphenylimidazole, tri (n-butyl) amine,
Tri (n-octyl) amine, N-phenyldiethanolamine, N-hydroxyethylpiperidine, 2,6-
Diisopropylaniline, N-cyclohexyl-N'-
Examples include, but are not limited to, morpholinoethylthiourea, N-hydroxyethylmorpholine, and the like.

Of these, particularly preferred compounds include 1,5-diazabicyclo [4,3,0] non-5-
Ene, 1,8-diazabicyclo [5,4,0] undec-7-ene, 2,4,5-triphenylimidazole,
Tri (n-butyl) amine, tri (n-octyl) amine, N-phenyldiethanolamine, N-hydroxyethylpiperidine, 2,6-diisopropylaniline,
N-cyclohexyl-N'-morpholinoethylthiourea and N-hydroxyethylmorpholine. These nitrogen-containing basic compounds are used alone or in combination of two or more. The amount of the nitrogen-containing basic compound used is usually 0.001 to 10% by weight, based on the solid content of the composition,
Preferably it is 0.01 to 5% by weight. If the amount is less than 0.001% by weight, the effect of the addition of the nitrogen-containing basic compound cannot be obtained. On the other hand, if it exceeds 10% by weight, the sensitivity tends to decrease and the developability of the unexposed portion tends to deteriorate.

[5] Other Additives, Positive Resist Composition Preparation Method, Usage Method, etc. An acid-decomposable dissolution inhibiting compound can be added to the positive resist composition of the present invention. Thereby, the contrast and the resolution are improved, and the pattern profile is made rectangular. Examples of the acid-decomposable dissolution-inhibiting compound include compounds that contain an acid-decomposable group, are decomposed by the action of an acid, and have increased solubility in an alkali developing solution. Compounds containing no group are preferred, and compounds having a monocyclic or polycyclic hydrocarbon structure are more preferred. Thereby, dry etching resistance is improved. Specific examples of the monocyclic or polycyclic hydrocarbon structure include a monocyclic cycloalkane structure, an adamantane structure, a norbornane structure, and a steroid structure, and more preferably an adamantane structure and a steroid structure. As the acid-decomposable group contained in the acid-decomposable dissolution-inhibiting compound, a group obtained by protecting a carboxylic acid with a group capable of leaving with an acid is preferable. Examples of such an acid-decomposable group include t-butyl ester and t-amyl. Examples thereof include tertiary alkyl ester groups such as esters, and linear or cyclic acetal ester groups such as 1-alkoxyethyl ester and 2-tetrahydropyranyl ester. Preferably it is a tertiary alkyl ester group. The amount of the acid-decomposable dissolution-inhibiting compound in the positive resist composition of the present invention is usually 1 to 30% by weight, preferably 5 to 20% by weight, based on the solid content of the composition.
It is.

The positive resist composition of the present invention may further contain a dye, a plasticizer, a sensitizer, a compound which promotes solubility in a developing solution, and the like, if necessary.

The photosensitive composition of the present invention is dissolved in a solvent capable of dissolving each of the above components and coated on a support. Examples of the solvent used herein include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, and ethylene glycol monoethyl ether acetate. , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate,
Ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable, and these solvents are used alone or in combination.

Among the above, preferred solvents are 2-
Heptanone, γ-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate , N-methylpyrrolidone and tetrahydrofuran.

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

As the antireflection film, an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, α-silicon, and an organic film type formed of a light absorbing agent and a polymer material can be used. The former requires equipment such as a vacuum deposition apparatus, a CVD apparatus, and a sputtering apparatus for film formation. As the organic antireflection film, for example, Japanese Patent Publication No. 7-69
611, a condensate of a formaldehyde-modified melamine resin with a diphenylamine derivative, an alkali-soluble resin,
A light absorbing agent or a reaction product of a maleic anhydride copolymer and a diamine type light absorbing agent described in US Pat. No. 5,294,680;
JP-A-6-118631, containing a resin binder and a methylolmelamine-based thermal crosslinking agent;
Acrylic resin type antireflection coating having a carboxylic acid group, an epoxy group and a light absorbing group in the same molecule as described in 18656, one comprising a methylolmelamine and a benzophenone-based light absorbing agent described in JP-A-8-87115, and described in JP-A-8-179509. Examples thereof include those obtained by adding a low-molecular-weight light absorbing agent to a polyvinyl alcohol resin. Also, as an organic anti-reflection film,
DUV30 series manufactured by Brewer Science,
DUV-40 series, Shipley's AC-2, AC
-3 can also be used.

The resist solution is applied onto a substrate (eg, a silicon / silicon dioxide coating) used for manufacturing precision integrated circuit devices (on a substrate provided with the antireflection film as required), a spinner, a coater, and the like. After coating by an appropriate coating method such as that described above, exposure through a predetermined mask, baking and development can provide a good resist pattern. Here, the exposure light is preferably 150
It is light having a wavelength of from nm to 250 nm, more preferably 220 nm or less. Specifically, a KrF excimer laser (248 nm) and an ArF excimer laser (193n)
m), F ₂ excimer laser (157 nm), X-ray, electron beam and the like.

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

[0133]

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

[Synthesis of Photoacid Generator as Component (A)] The compounds of the above general formulas (I) and (II) can be obtained by reacting an aryl Grignard reagent such as aryl magnesium bromide with a substituted or unsubstituted phenyl sulfoxide. Let
A method of salt-exchanging the obtained triarylsulfonium halide with a corresponding sulfonic acid, or using a substituted or unsubstituted phenylsulfoxide and a corresponding aromatic compound with an acid catalyst such as methanesulfonic acid / diphosphorus pentoxide or aluminum chloride. And a diaryl iodonium salt and a diaryl sulfide are condensed and exchanged with a catalyst such as copper acetate. The sulfonic acid or sulfonic acid salt used for the above-mentioned salt exchange can be obtained by hydrolysis of a commercially available sulfonic acid halide. Hereinafter, three examples of the synthesis of the photoacid generator as the component (A) will be described. Other photoacid generators used in Table 2 below are synthesized by the same method or the above-described general method. It was done.

Synthesis Example 1 <Synthesis of tri (t-butylphenyl) sulfonium perfluoro-n-butanesulfonate (I-2)>
Butylphenyl) sulfide (80 mmol), di (t
-Butylphenyl) iodonium perfluoro-n-butanesulfonate (20 mmol), copper benzoate (4 mm
ol) was stirred at 130 ° C. for 4 hours under a nitrogen stream. The reaction solution was allowed to cool, and 100 ml of ethanol was added thereto to remove a precipitate. Concentrate the filtrate and add ether 2
Upon addition of 00 ml, a powder precipitated, which was collected by filtration, washed with ether, and dried to obtain 5.1 g of the desired product.

Synthesis Example 2 <Synthesis of tri (t-butylphenyl) sulfonium perfluoro-n-octanesulfonate (I-4)> Using the same method as in Synthesis Example 1, di (t-butylphenyl) iodonium perfluoro Di (t-butylphenyl) iodonium perfluoro-in place of n-butanesulfonate
Using n-octanesulfonate, the target substance was 6.2 g.
Obtained.

Synthesis Example 3 <Synthesis of bis (p-chlorophenyl) phenylsulfonium perfluoro-n-butanesulfonate (I-6)>
100 g of bis (p-chlorophenyl) sulfoxide was dissolved in 800 ml of benzene, 295 g of aluminum chloride was added thereto, and the mixture was refluxed for 24 hours. The reaction solution was slowly poured into 2 L of water, and 400 ml of concentrated hydrochloric acid was added thereto.
Heated at ° C for 10 minutes. This aqueous solution is mixed with ethyl acetate 500
After washing with m1, an aqueous solution of bis (p-chlorophenyl) phenylsulfonium was obtained. An aqueous solution of 3.8 g of sodium trifluoromethanesulfonate was added to 150 ml of this aqueous solution. This was extracted with ethyl acetate, and the organic phase was washed with distilled water, dried and concentrated to obtain 4.3 g of the desired product.

[Synthesis of Resins (1) to (8) as Component (B)] Synthesis Example 4 <Synthesis of Resin (1)> Methacrylic acid ester of 3-oxo-1,1-dimethylbutanol and cyclopentadiene An equimolar mixture of a tetracyclododecene derivative (1-1) having the following structure and maleic anhydride obtained by a reaction with a diene is dissolved in tetrahydrofuran, and the solid content is 50%.
Was prepared. This was charged into a three-necked flask and heated at 60 ° C. under a nitrogen stream. When the reaction temperature was stabilized, 5 mol% of a radical initiator V-60 manufactured by Wako Pure Chemical Industries, Ltd. was added to start the reaction. After heating for 6 hours, the reaction mixture was diluted twice with tetrahydrofuran, and then poured into a large amount of hexane to precipitate a white powder. The precipitated powder was taken out by filtration and dried to obtain the intended resin (1).

[0139]

Embedded image

The molecular weight analysis of the obtained resin (1) by GPC was 6800 (weight average) in terms of polystyrene. From the NMR spectrum, it was found that the molar ratio of the repeating unit of tetracyclododecene and the repeating unit of maleic anhydride in the resin (1) was 50/50.

Resins (2) to (1) were prepared in the same manner as in Synthesis Example 4.
0) was synthesized. The structures of the synthesized resins (1) to (10) are described below.

[0142]

Embedded image

[0143]

Embedded image

[0144]

Embedded image

Table 1 shows the molar ratio and weight average molecular weight of each repeating structural unit of the resins (1) to (8).

[0146]

[Table 1]

Synthesis of Dissolution Inhibitor T-butyl cholate (2.07 g, 4.457 mmol) (previously dried under vacuum at 60 ° C. overnight) was placed in a Schlenk tube dried in an oven and purged with argon. ,
(Distilled from CaH ₂₎ N-methylmorpholine (1.
(1 mL, 10 mmol) and methylene chloride (8 mL).

The mixture is cooled to 0 ° C. and
Distilled glutaryl dichloride (0.552 g, 4.32 g)
(4 mmol, 97 mol%) was added slowly using an airtight syringe. As the addition was over, salt precipitation began. Stir the resulting slurry and add
Warm to room temperature over a period of
Warmed for minutes.

Thereafter, the mixture was treated with methylene chloride (40
mL) and water (40 mL). The organic layer was washed four times with dilute aqueous ammonium acetate and concentrated to give a solid. This solid was freeze-dried from dioxane to obtain a powder.

The powder was dispersed in water (100 mL) and stirred for one hour. The powder was recovered by filtration and dried in vacuo. The yield was 1.5 g (64% yield). When this method was repeated using tetrahydrofuran (THF), the yield was 1.7 g (74% yield). The structure of the resulting oligomer is shown below. This oligomer is referred to as a dissolution inhibitor A.

[0151]

Embedded image

Oligo (t-butylcholate-co-glutarate) end-capped with t-butylcholate (wherein
tBu represents a t-butyl substituent, and Y represents either hydrogen or another unit in the structure defined by parentheses having the subscript M or l. )

The number of units M per molecule is from about 5 to about 20. As mentioned above, the condensation reaction can take place at any OH group on the polycyclic compound. Therefore, the above structure is shown as an aid in explaining the reaction product, and not the actual structure of the obtained product.

[Examples 1 to 15 and Comparative Examples 1 to 6] (Preparation of positive resist composition solution) Various components shown in Table 2 were used in the following amounts. Resin shown in Table 2 synthesized in the above synthesis example: 2.0 g Photoacid generator: 0.02 g Organic basic compound (amine): 0.001 g Surfactant: 0.004 g Solid content concentration of composition of each example Was dissolved in propylene glycol monoethyl ether acetate so as to be 14% by weight, and filtered through a 0.1 μm microfilter to prepare positive resist composition solutions of Examples 1 to 12 and Comparative Examples 1 to 6. . When a dissolution inhibitor (dissolution inhibitor A or t-butyl cholate) is added, the amount of addition is 0.5.
g.

The photoacid generator, organic basic compound (amine) and surfactant used are as follows. Photoacid generator PAG-A; triphenylsulfonium perfluoro-n
-Butanesulfonate PAG-B; di (4-t-butylphenyl) iodonium trifluoromethanesulfonate PAG-C; di (4-t-butylphenyl) iodonium nonafluoro n-butanesulfonate PAG-D; 4-methoxy-1 -Naphthyltetrahydrothiophenium nonafluoro n-butanesulfonate PAG-E; N-trifluoromethanesulfonylsuccinimideamine (1); 1,5-diazabicyclo [4.3.0] -5-
Nonene (2); 2,4,5-triphenylimidazole (3); tri-n-butylamine (4); N-hydroxyethylpiperidine Surfactant W-1: Megafac F176 (Dainippon Ink Co., Ltd.)
(Fluorine) W-2: Megafac R08 (Dai Nippon Ink Co., Ltd.)
(Fluorine and silicone type) W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) W-4; Troysol S-366 (Troy Chemical Co., Ltd.)
(Silicon)

(Evaluation Test) The obtained positive resist composition solution was applied on a silicon wafer by using a spin coater, dried at 140 ° C. for 90 seconds to form a positive photoresist film of about 0.5 μm. It was exposed to ArF excimer laser (193 nm). A heat treatment after the exposure was performed at 140 ° C. for 90 seconds, developed with a 2.38% aqueous solution of tetramethylammonium hydroxide, and rinsed with distilled water to obtain a resist pattern profile.

[Sensitivity]: Defined as an exposure amount that reproduces a 0.18 μm line / space = 1/1 mask pattern. [Resolution]; 0.18 μm line / space = 1/1
Is defined by the critical resolution at the exposure dose that reproduces the mask pattern of [Particles]: prepared resist composition solution at 4 ° C.
After one week, the number of particles in the solution was counted using a particle counter manufactured by Rion. Table 2 shows the evaluation results.

[0158]

[Table 2]

As is evident from the results in Table 2, the positive resist compositions of Examples have excellent sensitivity and resolution.
The generation of particles is slight. On the other hand, in the case of the comparative example using the photoacid generator not included in the general formulas (I) and (II), particles were generated.

[0160]

Industrial Applicability The positive resist composition of the present invention is suitably applied particularly to light in the far ultraviolet wavelength range of 170 nm to 220 nm, has excellent sensitivity and resolving power, and generates little particles during storage. And has excellent storage stability.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshiaki Aoi 4000F, Kawajiri, Yoshida-cho, Haibara-gun, Shizuoka Prefecture F-term in Fujisha Shin Film Co., Ltd. CB45 CC04 CC20

Claims (9)

[Claims] (1) at least one compound selected from the compounds represented by the following general formulas (I) and (II), which generates an acid upon irradiation with actinic rays or radiation; Having at least one of the repeating structural units represented by the formula (Ia ′) and the general formula (Ib ′) and a repeating structural unit represented by the following general formula (II ′),
A positive resist composition comprising a polymer having a group that is decomposed by the action of an acid. Embedded image In the above general formulas (I) to (II), R _{1 to} R ₂₇ each independently represent a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group represents a halogen atom, or an -S-R ₂₈ group. R
₂₈ represents a linear, branched or cyclic alkyl or aryl group. However, among R _{1 to} R ₁₅ and R _{16 to} R ₂₇ ,
At least one is not a hydrogen atom. Also, R _1-
Two or more members out of R ₁₅ , R _{16 to} R ₂₇ may combine to form a ring containing one or more members selected from a single bond, carbon, oxygen, sulfur, and nitrogen. . X ^- is,
Represents R ^F SO ₃ ^— . Here, R ^F is a fluorine-substituted linear, branched or cyclic alkyl group having 2 or more carbon atoms. Embedded image In the formula (Ia ′): R ′ ₁ and R ′ ₂ each independently represent a hydrogen atom, a cyano group, a hydroxyl group, —COOH, —COOR ′ ₅ ,
_{CO-NH-R '6,} -CO-NH-SO 2 -R' 6, optionally substituted alkyl group, an optionally substituted alkoxy group or an optionally substituted cyclic hydrocarbon group, or The following -Y group is represented. Here, R ′ ₅ represents an alkyl group which may have a substituent, a cyclic hydrocarbon group which may have a substituent, or the following —Y group. R ′ ₆ represents an alkyl group which may have a substituent or a cyclic hydrocarbon group which may have a substituent. X represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or -NHSO ₂ NH-
Represents A represents a single bond or a divalent linking group. -Y group: (In the —Y group, R ′ _{21 to} R ′ ₃₀ each independently represent a hydrogen atom or an alkyl group which may have a substituent. A, b
Is 1 or 2.) In the formula (Ib ′): Z ₂ represents —O— or —N (R ′ ₃ ) —. Here, R ′ ₃ is a hydrogen atom, a hydroxyl group or —OSO ₂
-R 'represents a _4. R ₄ ′ represents an alkyl group, a haloalkyl group, a cycloalkyl group or a camphor residue. In the formula (II ′), R ′ ₁₁ and R ′ ₁₂ each independently represent a hydrogen atom, a cyano group, a halogen atom, or an alkyl group which may have a substituent. Z represents an atomic group containing two bonded carbon atoms (C-C) and forming an alicyclic structure which may have a substituent. 2. The repeating structural unit represented by the general formula (II ′) is represented by the following general formula (II′-A) or (II′-A):
The positive resist composition according to claim 1, which is a repeating structural unit represented by B). Embedded image In the general formulas (II′-A) and (II′-B), R ′ _{13 to} R ′ ₁₆ are
Each independently represents a hydrogen atom, a halogen atom, a cyano group, -C
OOH, -COOR '(the ₅ R' ₅ are as defined above), group decomposable by the action of an acid, -C (= O) -X- A-R '
₁₇ or an alkyl group or a cyclic hydrocarbon group which may have a substituent. Also, they may form a ring of at least two members to one of the R _'l3 ~R' _16. Here, X and A have the same meanings as above. R '17 _is-
COOH, -COOR _'5, -CN, hydroxyl, optionally substituted alkoxy _{group, -CO-NH-R' 6} , -
_{CO-NH-SO 2 -R '} 6 (R' 5, R '6 are each as defined above) represents a or above -Y groups. n is 0 or 1. Wherein X in the general formula (I) and (II) ^- the R ^F is CF ₃ (CF ₂₎ y (where, y is a is 1-9 integer) fluorine-substituted linear represented by The positive resist composition according to claim 1, wherein the positive resist composition is an alkyl group. 4. The positive resist composition according to claim 3, wherein y is an integer of 1 to 7. 5. The positive resist composition according to claim 4, wherein y is an integer of 1 to 4. 6. The positive resist composition according to claim 1, wherein the component (A) is a compound having the following structure. Embedded image X ^- has the same meaning as described above. 7. The positive resist composition according to claim 1, further comprising a nitrogen-containing basic compound. 8. The positive resist composition according to claim 1, further comprising a fluorine-based and / or silicon-based surfactant. 9. The positive resist composition according to claim 1, which is used for irradiation with actinic rays or radiation having a wavelength of 220 nm or less.