JP4448782B2 - Positive resist composition for immersion exposure and pattern forming method using the same - Google Patents

Description

  The present invention relates to a resist composition used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, and a lithography process for other photo applications, and a pattern forming method using the same. . In particular, the present invention relates to a resist composition suitable for exposure with an immersion type projection exposure apparatus that uses far-ultraviolet light having a wavelength of 300 nm or less as a light source, and a pattern forming method using the resist composition.

With the miniaturization of semiconductor elements, the exposure light source has become shorter in wavelength and the projection lens has a higher numerical aperture (high NA). Currently, an exposure machine with NA 0.84 using an ArF excimer laser having a 193 nm wavelength as a light source has been developed. ing. These can be expressed by the following equations as is generally well known.
(Resolving power) = k ₁ · (λ / NA)
(Depth of focus) = ± k ₂ · λ / NA ²
Here, λ is the wavelength of the exposure light source, NA is the numerical aperture of the projection lens, and k ₁ and k ₂ are coefficients related to the process.

An exposure machine using a F ₂ excimer laser having a wavelength of 157 nm as a light source has been studied for higher resolution by further shortening the wavelength. Lens materials and resists used in the exposure apparatus for shorter wavelength have been studied. Because the materials used in the process are very limited, it is very difficult to stabilize the manufacturing cost and quality of the apparatus and materials, and the exposure apparatus and resist that have sufficient performance and stability within the required period are not in time. The possibility is coming out.

As a technique for increasing the resolving power in an optical microscope, a so-called immersion method in which a high refractive index liquid (hereinafter also referred to as “immersion liquid”) is filled between a projection lens and a sample is known.
This “immersion effect” means that when λ ₀ is the wavelength of the exposure light in the air, n is the refractive index of the immersion liquid with respect to air, θ is the convergence angle of the light beam, and NA ₀ = sin θ. The above-described resolving power and depth of focus can be expressed by the following equations.
(Resolving power) = k ₁ · (λ ₀ / n) / NA ₀
(Depth of focus) = ± k ₂ · (λ ₀ / n) / NA ₀ ²
That is, the immersion effect is equivalent to using an exposure wavelength having a wavelength of 1 / n. In other words, in the case of a projection optical system with the same NA, the depth of focus can be increased n times by immersion. This is effective for all pattern shapes, and can be combined with a super-resolution technique such as a phase shift method and a modified illumination method which are currently being studied.

Examples of apparatuses in which this effect is applied to transfer of a fine image pattern of a semiconductor element include Patent Document 1 (Japanese Patent Publication No. 57-153433) and Patent Document 2 (Japanese Patent Laid-Open No. 7-220990). There is no discussion of resists suitable for immersion exposure techniques.
In Patent Document 3 (Japanese Patent Laid-Open No. 10-303114), it is pointed out that the refractive index control of the immersion liquid is important because the refractive index change of the immersion liquid causes deterioration of the projected image due to the wavefront aberration of the exposure machine. Disclosed is a water to which the temperature coefficient of the refractive index of the immersion liquid is controlled within a certain range, and as a suitable immersion liquid, an additive that lowers the surface tension or increases the surface activity is added. Has been. However, the disclosure of the additive and the resist suitable for the immersion exposure technique are not discussed.
Recent progress of immersion exposure technology is reported in Non-Patent Document 1 (SPIE Proc 4688, 11 (2002)), Non-Patent Document 2 (J. Vac. Sci. Tecnol. B 17 (1999)), and the like. In the case of using an ArF excimer laser as a light source, pure water (refractive index of 1.44 at 193 nm) is considered to be most promising as an immersion liquid in terms of handling safety, transmittance at 193 nm, and refractive index. When an F ₂ excimer laser is used as a light source, a solution containing fluorine has been studied from the balance between transmittance and refractive index at 157 nm. However, a sufficient product has not yet been seen in terms of environmental safety and refractive index. It has not been issued. From the degree of immersion effect and the degree of completeness of the resist, the immersion exposure technique is considered to be installed in the ArF exposure machine earliest.

Since the resist for KrF excimer laser (248 nm), an image forming method called chemical amplification has been used as an image forming method for a resist in order to compensate for sensitivity reduction due to light absorption. Taking a positive chemical amplification image forming method as an example, the acid generator in the exposed area is decomposed by exposure to generate an acid during exposure, and the generated acid is used as a reaction catalyst in post-exposure baking (PEB). In this image forming method, the alkali-insoluble group is changed to an alkali-soluble group, and the exposed portion is removed by alkali development.
In immersion exposure, the resist film and the optical lens are filled with an immersion liquid (also referred to as an immersion liquid) and exposed through a photomask to transfer the photomask pattern to the resist film. By penetrating the inside of the resist film, it is expected to affect a chemical reaction (acid-catalyzed deprotection reaction, development reaction) caused in the resist during or after exposure. However, the extent and mechanism of the effect is still unknown.

  When a chemically amplified resist is applied to the immersion exposure technique, the acid on the resist surface generated during exposure moves to the immersion liquid, and the acid concentration on the exposed portion surface changes. This was a major problem at the beginning of the development of chemically amplified positive resists. Exposure to PEB (PED: PostExposuretimeDelay) resulted in a few ppb levels of basic contamination from the environment resulting in acid loss on the exposed surface. Although it seems to be very similar to life, the influence and mechanism of immersion exposure on the resist have not been clarified yet. When a chemically amplified resist that does not have a problem with lithography in normal exposure is subjected to immersion exposure, the sensitivity is deteriorated as compared with that in normal dry exposure, and improvement thereof is necessary. Further, when the generated acid is eluted from the resist surface into the immersion water at the time of immersion exposure, there is a concern that the objective lens of the exposure machine is contaminated, and it has been required to reduce the generated acid as much as possible.

Japanese Patent Publication No.57-153433 JP-A-7-220990 JP-A-10-303114 Proc. SPIE, 2002, Vol. 4688, p. 11 J.Vac.Sci.Tecnol.B 17 (1999)

  In view of the problems of the conventional immersion exposure techniques as described above, the object of the present invention is suitable for immersion exposure in which the deterioration of sensitivity is small compared with the case of dry exposure and the acid elution into the immersion liquid is extremely small. It is to provide a resist.

  The present invention is a positive resist composition for immersion exposure having the following constitution, whereby the above object of the present invention is achieved.

(1) (A) Resin having at least one repeating unit represented by the following general formula (IIa) and having increased solubility in an alkaline developer by the action of an acid (however, represented by the following general formula (3) And a resin capable of generating an acid upon irradiation with actinic rays or radiation, except for a resin having a repeating unit by a fluorine-containing cyclic compound and a resin having a repeating unit represented by the following general formula (Ia)), and (B)
A positive resist composition for immersion exposure, comprising:

In general formula (IIa),
R _{x1 to} R _x3 each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or —L ₃ —C (R _f1 ) (R _f2 ) Ra.
R _f1 and R _f2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _f1 and R _f2 is a fluorine atom or a fluoroalkyl group.
Ra represents a hydrogen atom or a hydroxyl group.
L ₃ represents a single bond, an alkylene group, —CH ₂ —O— or —CH ₂ —COO—.
R ₁ and R _m each independently represents a hydrogen atom or an alkyl group.
Z ₁ represents a single bond, an alkylene group, a cycloalkylene group or an arylene group.
L ₁ represents a single bond or a divalent linking group.
n and q each independently represents 0 or 1.
r represents an integer of 1 to 6.

In general formula (3),
R ₁ b is a cyclic alkyl group having 1 to 25 carbon atoms, a cyclic alkenyl group, a cyclic alkynyl group, an aryl group, or a heterocyclic group, and includes a fluorine atom, oxygen atom, sulfur atom, nitrogen atom, carbon- An atomic group containing a carbon double bond may be included.
R _{2 to} R ₇ are each a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group having 1 to 25 carbon atoms, and includes a fluorine atom, an oxygen atom, a sulfur atom, a nitrogen atom, and a carbon-carbon atom. An atomic group containing a double bond may be included.
R ₈ is a carbonyl group or a methylene group, or a single bond.

Where
R ¹ represents a hydrogen atom, a methyl group, or —CH ₂ CO ₂ R ¹⁴ .
R ² represents a hydrogen atom, a methyl group, or —CO ₂ R ¹⁴ .
R ³ represents a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms.
R ^{4 to} R ⁹ , R ¹² and R ¹³ each independently represent a hydrogen atom or a monovalent hydrocarbon group which may contain a C 1-15 hetero atom, and R ¹⁰ and R ¹¹ represent a hydrogen atom. . Alternatively, R ⁴ and R ^5, R ⁶ and R ^8, R ⁶ and R ^9, R ⁷ and R ^9, R ⁷ and R ^13, R ⁸ and R ^12, R ¹⁰ and R ^11, R ¹¹ and R ¹² are The divalent hydrocarbon group which may form the ring mutually and may contain the C1-C15 hetero atom in that case is shown. R ⁴ and R ¹³ , R ¹⁰ and R ¹³ , and R ⁶ and R ⁸ may be bonded to adjacent carbons without any intervention to form a double bond.
R ¹⁴ represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms. The general formula (1a) also represents a mirror image.
(2) (A) Resin having at least one repeating unit represented by the following general formula (IIb) and having increased solubility in an alkaline developer by the action of an acid (however, represented by the following general formula (Ia)) Except for resins having repeating units)
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
A positive resist composition for immersion exposure, comprising:

In general formula (IIb),
R _{x1 to} R _x3 each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or —L ₃ —C (R _f1 ) (R _f2 ) Ra.
R _f1 and R _f2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _f1 and R _f2 is a fluorine atom or a fluoroalkyl group.
Ra represents a hydrogen atom or a hydroxyl group.
L ₃ represents a single bond, an alkylene group, —CH ₂ —O— or —CH ₂ —COO—.
R ₁ and R _m each independently represents a hydrogen atom or an alkyl group.
Z _1b represents a polycyclic cycloalkylene group.
L ₁ represents a single bond or a divalent linking group.
n and q each independently represents 0 or 1.
r represents an integer of 1 to 6.

Where
R ¹ represents a hydrogen atom, a methyl group, or —CH ₂ CO ₂ R ¹⁴ .
R ² represents a hydrogen atom, a methyl group, or —CO ₂ R ¹⁴ .
R ³ represents a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms.
R ^{4 to} R ⁹ , R ¹² and R ¹³ each independently represent a hydrogen atom or a monovalent hydrocarbon group which may contain a C 1-15 hetero atom, and R ¹⁰ and R ¹¹ represent a hydrogen atom. . Alternatively, R ⁴ and R ^5, R ⁶ and R ^8, R ⁶ and R ^9, R ⁷ and R ^9, R ⁷ and R ^13, R ⁸ and R ^12, R ¹⁰ and R ^11, R ¹¹ and R ¹² are The divalent hydrocarbon group which may form the ring mutually and may contain the C1-C15 hetero atom in that case is shown. R ⁴ and R ¹³ , R ¹⁰ and R ¹³ , and R ⁶ and R ⁸ may be bonded to adjacent carbons without any intervention to form a double bond.
R ¹⁴ represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms. The general formula (1a) also represents a mirror image.

(3) (A) a resin having at least one repeating unit selected from the group of the following general formulas (IV) to (IX) and having increased solubility in an alkali developer by the action of an acid;
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
A positive resist composition for immersion exposure, comprising:

X ₁ represents an oxygen atom or a sulfur atom.
X ₂ represents a methylene group, an oxygen atom or a sulfur atom.
Rx represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or a -L ₃ -Ra. L ₃ represents an alkylene group, —CH ₂ O—, or —CH ₂ O (C═O) —, and Ra represents a hydroxyl group, a lactone group, or a fluoroalkyl group.
Rf, Rf _1, Rf ₂ represents a group having at least one fluorine atom independently. Rf ₁ and Rf ₂ may be connected to each other to form a ring having — (CF ₂ ) n ₁ —. n ₁ represents an integer of 1 or more.
n represents 0.
j represents an integer of 1 to 3.
(4) The resin of component (A) further has a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pVI) (1 ) -Positive resist composition for immersion exposure according to any one of (3).

Where
R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z forms an alicyclic hydrocarbon group together with a carbon atom. Represents the necessary atomic group.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.
(5) The immersion exposure positive according to any one of (1) to (4), wherein the resin of component (A) further has a repeating unit represented by the following general formula (AI): Type resist composition.

In general formula (AI),
R _b0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any of the following general formula (Lc) or general formulas (V-1) to (V-5).


In general formula (Lc),
Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ and Re ₁ each independently represents a hydrogen atom or an alkyl group which may have a substituent.
m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In general formulas (V-1) to (V-5),
R _{1b to} R _5b each independently represents a hydrogen atom or an optionally substituted alkyl group, cycloalkyl group, alkoxy group, alkoxycarbonyl group, alkylsulfonylimino group or alkenyl group. Two of R _{1b to} R _5b may combine to form a ring.
(6) The immersion exposure positive according to any one of (1) to (5), wherein the resin of component (A) further has a repeating unit represented by the following general formula (AII): Type resist composition.

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

(7) having a fluorine atom selected from a repeating unit represented by formula (IIa), a repeating unit represented by formula (IIb), or a repeating unit selected from the group of formulas (IV) to (IX) The positive resist composition for immersion exposure according to any one of (1) to (6) , wherein the content of the repeating unit in the resin (A) is 10 mol% to 30 mol% .

(8) The positive resist composition for immersion exposure as described in any one of (1) to (7) above, which is for ArF excimer laser exposure.
(9) A pattern forming method comprising a step of forming a resist film from the resist composition according to any one of (1) to (8 ) above, subjecting the resist film to immersion exposure, and developing.
(10) The pattern forming method as described in (9) above, wherein the immersion exposure is exposure with an ArF excimer laser.

  According to the present invention, it is possible to provide a resist suitable for immersion exposure, in which the deterioration of sensitivity is small as compared with the case of dry exposure and the acid elution into the immersion liquid is extremely small.

Hereinafter, the compounds used in the present invention will be described in detail.
Although this invention is invention which concerns on said (1)-(10), it described for reference also about other matters.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group). _{Further, -C (R 1 R 2 R} 3) or -CR ₁ R ₂ R ₃ means a group of a group represented by each of R ₁ to R ₃ to the carbon atom bonded by a single bond.

(A) Resin having a fluorine atom and having increased solubility in an alkali developer by the action of an acid
In the present invention, the resin having a fluorine atom and having increased solubility in an alkaline developer by the action of an acid is selected from the group of the general formula (IIa), the general formula (IIb), or the general formulas (IV) to (IX). A resin having at least one type of repeating unit is used, but other resins are also described for reference.
The resist composition of the present invention contains at least one repeating unit having a fluorine atom, and contains a resin (hereinafter also referred to as a fluorine-containing resin) whose solubility in an alkaline developer is increased by the action of an acid. Features. By using a fluorine-containing resin as the resin contained in the resist composition, the elution of acid from the resist surface to the immersion liquid during immersion can be reduced, and the sensitivity deterioration during immersion exposure can be reduced accordingly. It becomes possible to prevent.
Here, the resin having increased solubility in an alkaline developer means a group that can be decomposed by an acid (hereinafter also referred to as “acid-decomposable group”) on the main chain or side chain of the resin, or both the main chain and side chain. ). Among these, a resin having a group that can be decomposed by an acid in its side chain is more preferable. Preferred groups as the group capable of decomposing with an acid are a group in which a hydrogen atom of a —COOH group or —OH group is substituted with a group capable of leaving with an acid. In the present invention, the acid-decomposable group is an acetal or tertiary ester group.

  As the repeating unit having a fluorine atom, the number of fluorine atoms contained per repeating unit is preferably 3 or more and 21 or less, and more preferably 6 or more and 18 or less.

Further, the fluorine-containing resin preferably contains at least one repeating unit having a fluorine atom, and preferably has one alicyclic hydrocarbon structure in any of the repeating units constituting the polymer. Examples of the alicyclic hydrocarbon group include groups having a monocyclo, bicyclo, tricyclo, or tetracyclo skeleton. The carbon number is preferably 6-30, and particularly preferably 7-25.
Below, the structural example of an alicyclic part (alicyclic structure) is shown among alicyclic hydrocarbon groups.

  In the present invention, preferred examples of the alicyclic moiety include adamantyl group, noradamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclohexyl group, cycloheptyl. Group, cyclooctyl group, cyclodecanyl group and cyclododecanyl group. More preferred are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, a cyclododecanyl group, and a tricyclodecanyl group.

Examples of the substituent for these alicyclic hydrocarbon groups include an alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group.
The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group or a butyl group, more preferably a methyl group, an ethyl group, a propyl group or an isopropyl group. Preferred 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.
These may be further substituted with a hydroxyl group, a halogen atom or an alkoxy group.
The alicyclic hydrocarbon group may be directly substituted with a fluorine atom, or may be further substituted.

  The repeating unit having a fluorine atom preferably contains at least one selected from the group of the following general formulas (I) to (III).

In the general formula (I),
R _k1 , R _k2 and R _k3 each independently represent a halogen atom, an alkyl group or an alkoxy group.
la represents an integer of 0 to 2, lb represents an integer of 0 to 6, and lc represents an integer of 0 to 7.
L ₁ represents a single bond or a divalent linking group.
n represents 0 or 1.
Y represents a hydrogen atom or an organic group.

In the general formula (II), R _{x1 to} R _x3 each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or —L ₃ —C (R _f1 ) (R _f2 ) Ra. To express.
R _f1 and R _f2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _f1 and R _f2 is a fluorine atom or a fluoroalkyl group.
Ra represents a hydrogen atom or a hydroxyl group.
L ₃ represents a single bond, an alkylene group, —CH ₂ —O— or —CH ₂ —COO—.
R ₁ and R _m each independently represents a hydrogen atom or an alkyl group.
Z ₁ represents a single bond, an alkylene group, a cycloalkylene group, or an arylene group.
L ₁ represents a single bond or a divalent linking group.
n and q each independently represents 0 or 1.
r represents an integer of 1 to 6.
Y represents a hydrogen atom or an organic group.

In the general formula (III),
R _{y1 to} R _y3 each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a cyano group, an alkyl group, an aryl group, an alkoxy group or an aralkyl group.
L ₁ represents a single bond or a divalent alkylene group.
Y represents a hydrogen atom or an organic group.
m and n each independently represents 0 or 1.

In the general formula (I),
Examples of the halogen atom for R _k1 , R _k2 and R _k3 include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferred.
The alkyl group as R _k1 , R _k2 and R _k3 may have a substituent and is preferably an alkyl group having 1 to 8 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or an n-butyl group. , Sec-butyl group, t-butyl group and the like. The alkyl group of R _k1 , R _k2 and R _k3 is preferably an alkyl group substituted with a fluorine atom, and the carbon number thereof is 1 to 8, preferably 1 or 2, more preferably 1 carbon. . A perfluoroalkyl group in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is preferred.
The alkoxy group of R _k1 , R _k2 and R _k3 may have a substituent, and is preferably an alkoxy group having 1 to 8 carbon atoms, such as methoxy group, ethoxy group, propoxy group, n-butoxy group, etc. Can be mentioned.
Examples of the substituent that the alkyl group and alkoxy group as R _k1 , R _k2 and R _k3 may have include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom). ), Acyl group, acyloxy group, cyano group, hydroxyl group, carboxy group, alkoxycarbonyl group, nitro group and the like.

R _k1 , R _k2 and R _k3 are preferably a halogen atom or a fluorine-substituted alkyl group, particularly preferably a fluorine atom or a trifluoromethyl group.

  la represents an integer of 0 to 2, lb represents an integer of 0 to 6, lc represents an integer of 0 to 7, and la is preferably 0, lb is 0, and lc is an integer of 0 to 3.

Examples of the divalent linking group of L ₁ include an alkylene group, a cycloalkylene group, an alkenylene group, an arylene group, —O—, —S—, —O—R _22a —, —O—C (═O) —. R _22b —, —C (═O) —O—R _22c —, —C (═O) —N (R _22d ) —R _22e — and the like can be mentioned. R _22a , R _22b , R _22c and R _{22e each} may have a single bond or an ether group, an ester group, an amide group, a urethane group or a ureido group, a divalent alkylene group, a cycloalkylene group, an alkenylene. Represents a group or an arylene group. R _22d is a hydrogen atom or an alkyl group (preferably having 1 to 5 carbon atoms), a cycloalkyl group (preferably having 3 to 10 carbon atoms), an aralkyl group (preferably having 7 to 10 carbon atoms), or an aryl group (preferably carbon). Equations 6 to 10) are expressed.
The alkylene group is preferably a linear or branched alkylene group having 1 to 8 carbon atoms, and examples thereof include a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, and an octylene group.
The cycloalkylene group is preferably a cycloalkylene group having 5 to 12 carbon atoms, and examples thereof include monocyclic residues such as cyclopentylene group and cyclohexylene group, and polycyclic residues such as normolnan skeleton and adamantane skeleton. be able to.
The alkenylene group is preferably an alkenylene group having 2 to 6 carbon atoms, and examples thereof include an ethenylene group, a propenylene group, and a butenylene group.
The arylene group is preferably an arylene group having 6 to 15 carbon atoms, and examples thereof include a phenylene group, a tolylene group, and a naphthylene group.

Examples of the substituent that the divalent linking group of L ₁ may have include a halogen atom such as a fluorine atom and a chlorine atom, a cyano group, and the like, and a fluorine atom is preferable.
L ₁ is preferably a single bond, a methylene group or an —O— group.

Examples of the alkylene group for X include those having 1 to 8 carbon atoms such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, and an octylene group.
Examples of the alkenylene group of X include those having 2 to 6 carbon atoms such as ethenylene group, propenylene group and butenylene group.
Examples of the cycloalkylene group represented by X include those having 5 to 8 carbon atoms such as a cyclopentylene group and a cyclohexylene group.
Examples of the arylene group for X include those having 6 to 15 carbon atoms such as a phenylene group, a tolylene group, and a naphthylene group.

The organic group for Y includes both acid-decomposable and non-acid-decomposable ones, and preferably has 1 to 30 carbon atoms. Examples of the acid-decomposable organic group for Y include -C (R _11a ) (R _12a ) (R _13a ), -C (R _14a ) (R _15a ) (OR _16a ), -Xa-COO-C ( R _11a ) (R _12a ) (R _13a ) and the like.
R _{11a to} R _13a and R _16a each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group.
R _14a and R _15a each independently represents a hydrogen atom or an alkyl group.
Two of R _11a , R _12a , and R _13a and two of R _14a , R _15a , and R _16a may be bonded to form a ring.
Xa represents a single bond, an alkylene group, a cycloalkylene group, an alkenylene group or an arylene group.

As the alkyl group for R _{11a to} R _13a , R _14a , R _15a and R _16a , an alkyl group having 1 to 8 carbon atoms which may have a substituent is preferable, and examples thereof include a methyl group, an ethyl group, Propyl group, n-butyl group, sec-butyl group, hexyl group, 2-ethylhexyl group, octyl group, fluoroalkyl group (monofluoromethyl group, difluoromethyl group, trifluoromethyl group, pentafluoroethyl group, etc.) be able to. Of the fluoroalkyl groups, a trifluoromethyl group is most preferred.
The cycloalkyl group for R _{11a to} R _13a and R _16a may have a substituent, and may be monocyclic or polycyclic. The monocyclic type is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclobutyl group, and a cyclooctyl group. As the polycyclic type, a cycloalkyl group having 6 to 20 carbon atoms is preferable. For example, an adamantyl group, norbornyl group, isobornyl group, camphanyl group, dicyclopentyl group, α-pinel group, tricyclodecanyl group, tetocyclo A dodecyl group, an androstanyl group, etc. can be mentioned. A part of carbon atoms in the cycloalkyl group may be substituted with a hetero atom such as an oxygen atom.

The aryl group of R _{11a to} R _13a and R _16a may have a substituent, and is preferably an aryl group having 6 to 10 carbon atoms. For example, a phenyl group, a tolyl group, a dimethylphenyl group, 2, A 4,6-trimethylphenyl group, a naphthyl group, an anthryl group, a 9,10-dimethoxyanthryl group, etc. can be mentioned.
The aralkyl group of R _{11a to} R _13a and R _16a may have a substituent and is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group. Can do.
The alkenyl group of R _{11a to} R _13a and R _16a may have a substituent, and is preferably an alkenyl group having 2 to 8 carbon atoms, such as a vinyl group, an allyl group, a butenyl group, or a cyclohexenyl group. Etc.
The substituents that R _{11a to} R _13a , R _14a , R _15a , and R _16a may have include an alkyl group, a cycloalkyl group, an aryl group, an amino group, an amide group, a ureido group, a urethane group, and a hydroxy group. Carboxy group, halogen atom, alkoxy group, thioether group, acyl group, acyloxy group, alkoxycarbonyl group, cyano group, nitro group and the like.

  Preferred examples of the acid-decomposable group for Y include a t-butyl group, a t-amyl group, a 1-alkyl-1-cyclohexyl group, a 2-alkyl-2-adamantyl group, a 2-adamantyl-2-propyl group, Tertiary alkyl groups such as 2- (4-methylcyclohexyl) -2-propyl group, acetal groups such as 1-alkoxy-1-ethoxy group, 1-alkoxy-1-methoxy group and tetrahydropyranyl group, t-alkyl Preferred examples include a carbonyl group and a t-alkylcarbonylmethyl group.

  The non-acid-decomposable organic group of Y is an organic group that is not decomposed by the action of an acid, for example, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group that is not decomposed by the action of an acid. , Alkoxy groups, alkoxycarbonyl groups, amide groups, cyano groups, and the like. The alkyl group is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group, or a 2-ethylhexyl group. And octyl group. The cycloalkyl group preferably has 3 to 10 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclohexyl group, and an adamantyl group. The aryl group is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthracenyl group. The aralkyl group is preferably an aralkyl group having 6 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a cumyl group. The alkoxy group in the alkoxy group and the alkoxycarbonyl group is preferably an alkoxy group having 1 to 5 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, and an isobutoxy group.

  Preferred specific examples of the repeating unit represented by the general formula (I) are shown below, but the present invention is not limited thereto.

In the general formula (II),
Examples of the alkyl group of R _{x1 to} R _x3 include the same alkyl groups as Rk _{1 to} Rk ₃ in the general formula (I).
In the case where R _{x1 to} R _x3 are groups represented by -L ₃ -C (R _f1 ) (R _f2 ) Ra;
Examples of the alkyl group for R _f1 and R _f2 include the same alkyl groups as Rk _{1 to} Rk ₃ in the general formula (I).
As the alkylene group for L _3, the same divalent alkylene groups as L ₁ in the above general formula (I) can be exemplified.
As the alkyl group for R ₁ and R _m , an alkyl group having 1 to 3 carbon atoms is preferable, and specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a fluoroalkyl group. Of the groups, a methyl group is most preferred. As the fluoroalkyl group, those having 1 to 4 carbon atoms are preferable. Specifically, a monofluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, etc. However, a trifluoromethyl group is most preferable.
As the alkylene group for Z _1, the same divalent alkylene groups as L ₁ in the above general formula (I) can be exemplified.
The cycloalkylene group for Z ₁ may have a substituent and may be monocyclic or polycyclic. Examples of the substituent include a hydroxyl group, an alkyl group, an alkoxy group, a halogen atom, and a cyano group. The monocyclic type preferably has 3 to 8 carbon atoms, and examples thereof include a cyclopropylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, and a cyclooctylene group. The polycyclic type has 6 to 20 carbon atoms, such as adamantyl residue, norbornyl residue, isobornyl residue, camphanyl residue, dicyclopentyl residue, α-pinel residue, tricyclodecanyl residue. Preferred examples include a group, a tetocyclododecyl residue, an androstanyl residue, and the like. Moreover, the carbon atom in said monocyclic or polycyclic cycloalkyl group may be substituted by a hetero atom such as an oxygen atom. As the substituent of the cycloalkylene group, a fluorine atom is preferable. As the cycloalkylene group substituted with a fluorine atom (a cycloalkylene group in which at least one hydrogen atom is substituted with a fluorine atom), for example, a perfluorocyclopropylene group Perfluorocyclopentylene group, perfluorocyclohexylene group, perfluorocycloheptylene group, perfluorocyclooctylene group and the like.
As the arylene group for Z _1, an arylene group having 4 to 20 carbon atoms is preferable, and examples thereof include a phenylene group, a tolylene group, and a naphthylene group.
As the divalent linking group represented by L _1, it can be the same as the divalent linking group as L ₁ in formula (I).
Examples of the organic group for Y include the same organic groups as Y in the general formula (I) described above.

  Hereinafter, although the specific example of the repeating unit represented by general formula (II) is given, it is not limited to these.

In the general formula (III),
_Examples of the alkyl group represented by R _{y1 to} R _y3 include the same alkyl groups as R _k1 in the general formula (I) described above.
The aryl group of R _{y1 to} R _y3 is preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group, a tolyl group, a dimethylphenyl group, a 2,4,6-trimethylphenyl group, a naphthyl group, an anthryl group. , 9,10-dimethoxyanthryl group and the like.
Examples of the alkoxy group represented by R _{y1 to} R _y3 include the same alkoxy groups as Rk1 in the general formula (I).
As the aralkyl group of R _{y1 to} R _y3, an aralkyl group having 7 to 12 carbon atoms is preferable, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.
The divalent alkylene group of L _1, include the same divalent alkylene group as L ₁ in formula (I).
Examples of the organic group for Y include the same organic groups as Y in the general formula (I).

  Preferable specific examples of the repeating unit represented by the formula (III) include the following.

  Moreover, it is also preferable that the fluorine-containing resin of the present invention contains fluorine-containing repeating units represented by the following general formulas (IV) to (IX).

X ₁ represents an oxygen atom or a sulfur atom.
X ₂ represents a methylene group, an oxygen atom or a sulfur atom.
Rx represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or a -L ₃ -CRa. L ₃ represents an alkylene _{group, -CH 2 O -, - CH} 2 O (C = O) - represents, Ra represents a hydroxyl group, a lactone group, a fluoroalkyl group.
Rf, Rf ₁ and Rf ₂ each independently represents a group having at least one fluorine atom. Rf ₁ and Rf ₂ may be connected to each other to form a ring having — (CF ₂ ) n ₁ —. n ₁ represents an integer of 1 or more.
j represents an integer of 1 to 3.

In the general formulas (IV) to (IX), examples of the alkyl group include the same alkyl groups as Rk _{1 to} Rk ₃ in the general formula (I), and examples of the alkylene group include the above general formula (I It includes the same ones as divalent alkylene group as L ₁ in).
The lactone group preferably has a lactone structure represented by any one of the following general formula (Lc) or the following general formulas (V-1) to (V-5).
As the fluoroalkyl group, those having 1 to 4 carbon atoms are preferable, and specifically, a monofluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, Hexafluoroisopropyl group, nonafluoro-t-butyl group, trifluoroisopropyl group and the like can be mentioned.
n1 is an integer greater than or equal to ₁ , Preferably it is 3-6.

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

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

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

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

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

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

  In the fluorine-containing resin of the present invention, the fluorine-containing repeating units represented by the above general formulas (I) to (IX) are preferably used, but the fluorine-containing repeating units represented by the following general formulas (X) to (XV) are preferably used. Units may be included.

In general formula (X), R _1a represents a hydrogen atom, a fluorine atom, a hydrogen atom, a bromine atom, a cyano group or a trifluoromethyl group.
Y represents a hydrogen atom or an organic group.
na represents an integer of 1 to 5. When na is 2 or more, two or more R _{11 to} R ₁₆ and Y may be the same or different.

In the general formula (X),
Examples of the organic group for Y include the same organic groups as Y in the general formula (I).

  Hereinafter, although the specific example of the repeating unit represented by general formula (X) is given, it is not limited to these.

In the general formulas (XI) to (XIII), R ₀ and R _{1 each} represents a hydrogen atom, a fluorine atom, or an alkyl group, cycloalkyl group, or aryl group which may have a substituent.
R _{2 to} R ₄ represent an alkyl group, a cycloalkyl group, or an aryl group, which may have a substituent. R ₀ and R ₁ , R ₀ and R ₂ , R ₃ and R ₄ may combine to form a ring.

Examples of the alkyl group represented by R _{0 to} R ₄ include the same groups as the fluoroalkyl groups represented by R _{x1 to} R _x3 in the general formula (II).
The cycloalkyl group represented by R _{0 to} R ₄ may have a substituent, and may be monocyclic or polycyclic. The monocyclic type is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclobutyl group, and a cyclooctyl group. As the polycyclic type, a cycloalkyl group having 6 to 20 carbon atoms is preferable. For example, an adamantyl group, norbornyl group, isobornyl group, camphanyl group, dicyclopentyl group, α-pinel group, tricyclodecanyl group, tetocyclo A dodecyl group, an androstanyl group, etc. can be mentioned. A part of carbon atoms in the cycloalkyl group may be substituted with a hetero atom such as an oxygen atom.
The aryl group of R _{0 to} R ₄ may have a substituent, and is preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group, a tolyl group, a dimethylphenyl group, 2,4,6- Examples thereof include a trimethylphenyl group, a naphthyl group, an anthryl group, and a 9,10-dimethoxyanthryl group.

  Hereinafter, although the specific example of the repeating unit represented by general formula (XI)-(XIII) is given, it is not limited to these.

In general formula (XIV), R ₂₃ and R ₂₄ may be the same or different and each represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group, a fluoroalkyl group, or an alkoxy group.
Y represents a hydrogen atom or an organic group.

Examples of the alkyl group for R ₂₃ and R ₂₄ include the same alkyl groups as R _k1 in the above general formula (I).
Examples of the alkoxy group of R ₂₃ and R ₂₄ include the same alkoxy groups as R _k1 in the general formula (I) described above.
Examples of the organic group for Y include the same organic groups as Y in the general formula (I).

  Hereinafter, although the specific example of the repeating unit represented by general formula (XIV) is given, it is not limited to these.

In general formula (XV):
Rx represents a single bond or a divalent alkylene group.
Ry represents a hydrogen atom, a fluorine atom, or an alkyl group.
Y represents a hydrogen atom or an organic group.

In general formula (XV):
The divalent alkylene group represented by Rx is preferably one having 1 to 6 carbon atoms, and more preferably a methylene group, an ethylene group or a propylene group.
Examples of the alkyl group of Ry include the same alkyl groups as R _{x1 to} R _x3 in the general formula (II).
Examples of the organic group for Y include the same organic groups as Y in the general formula (I).

  Hereinafter, although the specific example of the repeating unit represented by general formula (XV) is given, it is not limited to these.

As the repeating unit containing these fluorine atoms, a commercially available one can be used, and it can also be synthesized by a usual method.
For example, the following monomer (IV-a) can be synthesized by esterifying the following compound (a). Compound (a) can also be synthesized from the following compound (b) obtained by Diels-Alder reaction of furan and trifluoromethylacrylic acid.

In the fluorine-containing resin of the present invention, the content of the repeating unit containing a fluorine atom as described above is usually 5 to 100 mol%, preferably 7 to 80 mol%, more preferably 10 in the resin (A). It is -30 mol%, More preferably, it is 20-30 mol%, Most preferably, it is 25 mol%-30 mol%.
However, when the immersion exposure resist of the present invention is used for ArF excimer laser applications, the content in the case of copolymerizing the repeating unit represented by the general formula (X) from the viewpoint of resin transparency is 1 mol% to 15 mol. %, More preferably 2 mol% to 7 mol%.

  In addition to the repeating unit having a fluorine atom as described above, an arbitrary repeating unit can be copolymerized in the resin of component (A), and in particular, the following general formula (pI) to general formula ( It is preferable to contain at least one selected from the group consisting of repeating units having a partial structure containing an alicyclic hydrocarbon represented by pVI) and repeating units represented by the following general formula (II-AB).

(Wherein R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z represents an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to form.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring. )

In formula (II-AB):
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 for forming an alicyclic structure which contains two bonded carbon atoms (C—C) and may have a substituent.

  The general formula (II-AB) is more preferably the following general formula (II-A) or general formula (II-B).

In formulas (II-A) and (II-B):
R ₁₃ ′ to R ₁₆ ′ each independently represents a hydrogen atom, a halogen atom, a cyano group, —COOH, —COOR ₅ , a group that decomposes by the action of an acid, —C (═O) —XA′—R. ₁₇ ′ represents an alkyl group or a cyclic hydrocarbon group which may have a substituent.
Here, R ₅ represents an alkyl group, a cyclic hydrocarbon group, or the following —Y group, which may have a substituent.
X 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.
Further, at least two of R ₁₃ ′ to R ₁₆ ′ may be bonded to form a ring. n represents 0 or 1.
R ₁₇ ′ is —COOH, —COOR ₅ , —CN, a hydroxyl group, an optionally substituted alkoxy group, —CO—NH—R ₆ , —CO—NH—SO ₂ —R ₆ or -Y group is represented.
R ₆ represents an alkyl group or a cyclic hydrocarbon group which may have a substituent. The -Y group;

(In the —Y group, R ₂₁ ′ to R ₃₀ ′ each independently represents a hydrogen atom or an optionally substituted alkyl group. A and b represent 1 or 2.)

In the general formulas (pI) to (pVI), the alkyl group in R _{12 to} R ₂₅ may be substituted or unsubstituted, and is a linear or branched alkyl group having 1 to 4 carbon atoms. Represents. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group.
Further, the further substituent of the alkyl group includes an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, A carboxy group, an alkoxycarbonyl group, a nitro group, etc. can be mentioned.

The alicyclic hydrocarbon group in R _{11 to} R _{25 or} the alicyclic hydrocarbon group formed by Z and a carbon atom may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These alicyclic hydrocarbon groups may have a substituent.

  Preferred examples of the alicyclic hydrocarbon group include an adamantyl group, a noradamantyl group, a decalin residue, a tricyclodecanyl group, a tetracyclododecanyl group, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Group, cyclodecanyl group, and cyclododecanyl group. More preferred are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group.

Examples of the substituent for these alicyclic hydrocarbon groups include an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group.
The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably a substituent selected from the group consisting of a methyl group, an ethyl group, a propyl group, and an isopropyl group. To express. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

The structures represented by the general formulas (pI) to (pVI) in the resin can be used for protecting alkali-soluble groups. Examples of the alkali-soluble group include various groups known in this technical field.
Specific examples include a carboxylic acid group, a sulfonic acid group, a phenol group, and a thiol group, and a carboxylic acid group and a sulfonic acid group are preferable.
As the alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI) in the above resin, the hydrogen atom of the carboxyl group is preferably substituted with the structure represented by the general formula (pI) to (PVI). Structure.

In the general formula (II-AB), 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 for forming an alicyclic structure which contains two bonded carbon atoms (C—C) and 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.
As the alkyl group in R ₁₁ ′, R ₁₂ ′, and R ₂₁ ′ to R ₃₀ ′, a linear or branched alkyl group having 1 to 10 carbon atoms is preferable, and more preferably 1 to 6 carbon atoms. It is a linear or branched alkyl group, 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, or a t-butyl group.

  Examples of the further substituent in the above alkyl 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, and examples of the acyloxy group include an acetoxy group.

The atomic group for forming the alicyclic structure of Z ′ is an atomic group that forms a repeating unit of an alicyclic hydrocarbon which may have a substituent in a resin, and among them, a bridged type alicyclic group. An atomic group for forming a bridged alicyclic structure forming a cyclic hydrocarbon repeating unit is preferred.
Examples of the skeleton of the alicyclic hydrocarbon formed include the same alicyclic hydrocarbon groups as R _{11 to} R _{25 in} the general formulas (pI) to (pVI).

The alicyclic hydrocarbon skeleton may have a substituent. Examples of such a substituent include R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or (II-B).
Among the repeating units having the bridged alicyclic hydrocarbon, the repeating unit represented by the general formula (II-A) or (II-B) is more preferable.

The acid-decomposable group in the resin according to the present invention may be contained in the aforementioned —C (═O) —XA′—R ₁₇ ′, or as a substituent for Z ′ in the general formula (II-AB). May be included.
The structure of the acid-decomposable group is represented by —C (═O) —X ₁ —R ₀ .
In the formula, R ₀ is a tertiary alkyl group such as t-butyl group or t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxy. 1-alkoxyethyl group such as ethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3- An oxocyclohexyl ester group, a 2-methyl-2-adamantyl group, a mevalonic lactone residue and the like can be mentioned. X ₁ has the same meaning as X 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 in R ₅ , R ₆ and R ₁₃ ′ to R ₁₆ ′ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear chain having 1 to 6 carbon atoms. Or a branched alkyl group, 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, or a t-butyl group.

Examples of the cyclic hydrocarbon group in R ₅ , R ₆ and R ₁₃ ′ to R ₁₆ ′ include a cyclic alkyl group and a bridged hydrocarbon group, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, 2- List methyl-2-adamantyl group, norbornyl group, boronyl group, isobornyl group, tricyclodecanyl group, dicyclopentenyl group, nobornane epoxy group, menthyl group, isomenthyl group, neomenthyl group, tetracyclododecanyl group, etc. Can do.
Examples of the ring formed by combining at least two of R ₁₃ ′ to R ₁₆ ′ include rings having 5 to 12 carbon atoms such as cyclopentene, cyclohexene, cycloheptane, and cyclooctane.

Examples of the alkoxy group for R ₁₇ ′ 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 further substituents in 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, an acyloxy group, an alkyl group, and a cyclic hydrocarbon group. Can do. 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.
Examples of the alkyl group and cyclic hydrocarbon group include those listed above.

  The divalent linking group of A ′ is selected from the group consisting of an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, and a urea group. Single or a combination of two or more groups may be mentioned.

  In the resin according to the present invention, the group decomposed by the action of an acid is a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the general formula (pI) to the general formula (pVI), a general formula (II -AB) and at least one repeating unit among the repeating units of the copolymerization component described below.

Various substituents of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or the general formula (II-B) are atomic groups for forming an alicyclic structure in the general formula (II-AB). Or it becomes a substituent of atomic group Z for forming a bridged alicyclic structure.

  Specific examples of the repeating unit represented by the general formula (II-A) or the general formula (II-B) include the following, but the present invention is not limited to these specific examples.

  The resin of the present invention preferably has a lactone group, more preferably a group having a lactone structure represented by any of the following general formula (Lc) or the following general formulas (V-1) to (V-5). A group having a lactone structure may be directly bonded to the main chain.

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ each independently represent a hydrogen atom or an alkyl group that may have a substituent. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.

In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom or an optionally substituted alkyl group, cycloalkyl group, alkoxy group, alkoxy group. A carbonyl group, an alkylsulfonylimino group or an alkenyl group is represented. Two of R _{1b to} R _5b may combine to form a ring.

R _{1 to} Re ₁ alkyl groups in general formula (Lc) and R _{1b to} R _5b alkyl groups, alkoxy groups, alkoxycarbonyl groups, alkyl groups in general formulas (V-1) to (V-5) Examples of the alkyl group in the sulfonylimino group include linear and branched alkyl groups, which may have a substituent.

As the repeating unit having a group having a lactone structure represented by general formula (Lc) or any one of general formulas (V-1) to (V-5), the above general formula (II-A) or (II- B) wherein at least one of R ₁₃ ′ to R ₁₆ ′ has a group represented by general formula (Lc) or general formula (V-1) to (V-5) (for example, R in —COOR ₅ ) ₅ represents a group represented by general formula (Lc) or general formulas (V-1) to (V-5)), or a repeating unit represented by the following general formula (AI).

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. As a preferable substituent that the alkyl group of R _b0 may have, as a preferable substituent that the alkyl group as R _1b in the general formulas (V-1) to (V-5) may have. What was illustrated previously is mentioned.
Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R _b0 is preferably a hydrogen atom.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

  Specific examples of the repeating unit having a group having a lactone structure are shown below, but the present invention is not limited thereto.

  The resin of the present invention may contain a repeating unit having a group represented by the following general formula (VII).

In general formula (VII), R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.

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

As the repeating unit having a group represented by the general formula (VII), at least one of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or (II-B) is the above general formula (VII ) (For example, R _{5 in} —COOR ₅ represents a group represented by the general formula (VII)), or a repeating unit represented by the following general formula (AII). it can.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group. _{Two of} R ₂ c to R ₄ c are preferably hydroxyl groups.

  Although the specific example of the repeating unit which has a structure represented by general formula (AII) below is given, it is not limited to these.

  The resin of the present invention may contain a repeating unit represented by the following general formula (VIII).

In the general formula (VIII), Z ₂ represents —O— or —N (R ₄₁ ) —. Here, R ₄₁ represents a hydrogen atom, a hydroxyl group, an alkyl group, or —OSO ₂ —R ₄₂ . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue.

  Specific examples of the repeating unit represented by the general formula (VIII) include the following [I′-1] to [I′-7], but the present invention is not limited to these specific examples. .

  In addition to the repeating structural units described above, the resin of the present invention adjusts dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required properties of resist, such as resolution, heat resistance, and sensitivity. For this purpose, various repeating structural units can be contained.

Examples of such a repeating structural unit include, but are not limited to, repeating structural units corresponding to the following monomers.
As a result, the performance required for the resin, especially
(1) Solubility in coating solvent,
(2) Film formability (glass transition point),
(3) Alkali developability,
(4) Membrane slip (hydrophobic, alkali-soluble group selection),
(5) Adhesion of unexposed part to substrate,
(6) Fine adjustment such as dry etching resistance can be performed.
As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

  In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.

  In the resin of the present invention, the molar ratio of each repeating structural unit is the resist dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general resist performance such as resolution, heat resistance, and sensitivity. It is set appropriately in order to adjust etc.

In the resin of the present invention, the content of the repeating unit having a partial structure containing an alicyclic hydrocarbon represented by general formulas (pI) to (pVI) is preferably 20 to 70 mol% in all repeating structural units, More preferably, it is 24-65 mol%, More preferably, it is 28-60 mol%.
In the resin of the present invention, the content of the repeating unit represented by the general formula (II-AB) is preferably 10 to 60 mol%, more preferably 15 to 55 mol%, still more preferably 20 in all repeating structural units. ˜50 mol%.

  In addition, the content of the repeating structural unit based on the monomer of the further copolymer component in the resin can also be appropriately set according to the performance of the desired resist. 99 mol% with respect to the total number of moles of the repeating structural unit having a partial structure containing the alicyclic hydrocarbon represented by (pVI) and the repeating unit represented by the above general formula (II-AB) The following is preferable, More preferably, it is 90 mol% or less, More preferably, it is 80 mol% or less.

The fluorine-containing resin used in the present invention can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, monomer species are charged into a reaction vessel in a batch or in the course of reaction, and this is added to a reaction solvent, for example, cyclic ethers such as tetrahydrofuran and 1,4-dioxane, methyl ethyl ketone, methyl isobutyl. Ketones, ketones such as cyclohexanone, and the composition of the present invention such as propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether, which will be described later, are uniformly dissolved in a solvent, and then inert gas such as nitrogen or argon. Polymerization is started using a commercially available radical initiator (azo initiator, peroxide, etc.) as necessary under an atmosphere. If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery. The concentration of the reaction is 10% by mass or more, preferably 15% by mass or more, and more preferably 20% by mass or more. The reaction temperature is 10 ° C to 150 ° C, preferably 30 ° C to 130 ° C, more preferably 50 ° C to 110 ° C.
The repeating structural units represented by the above specific examples may be used singly or in combination.
In the present invention, the resins may be used alone or in combination.

The weight average molecular weight of the resin according to the present invention is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, as a polystyrene converted value by the GPC method. It is preferable that the weight average molecular weight is in the above range in order to achieve both heat resistance and dry etching resistance and developability and film forming property.
The molecular weight distribution is usually 1 to 5, preferably 1 to 4, more preferably 1 to 3. A molecular weight distribution of 5 or less is preferable from the viewpoints of resolution, resist shape and prevention of roughness of the resist pattern side wall, and roughness.

  In the positive resist composition of the present invention, the blending amount of all the resins according to the present invention in the entire composition is preferably 40 to 99.99% by mass, more preferably 50 to 99.97, based on the total solid content of the resist. % By mass.

(B) Compound that generates acid upon irradiation with actinic ray or radiation Compound that generates acid upon irradiation with actinic ray or radiation (hereinafter referred to as “acid generator”) used in the resist composition for immersion exposure of the present invention Will be described below.
The acid generator used in the present invention can be selected from compounds generally used as an acid generator.
That is, it generates an acid upon irradiation with actinic rays or radiation used for photoinitiators of photocationic polymerization, photoinitiators of photoradical polymerization, photodecolorants of dyes, photochromic agents, or microresists. Known compounds and mixtures thereof can be appropriately selected and used.

  Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  Further, a group that generates an acid upon irradiation with these actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the polymer, for example, US Pat. No. 3,849,137, German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in JP-A 63-146029 can be used.

  Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Preferred compounds among the acid generators include compounds represented by the following general formulas (ZI), (ZII), and (ZIII).

In the above general formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a non-nucleophilic anion.
The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.

The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (Z1-1), (Z1-2) and (Z1-3) described later.

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (ZI) is, at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) It may be a compound.

  More preferable examples of the (ZI) component include compounds (Z1-1), (Z1-2), and (Z1-3) described below.

Compound (Z1-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.

In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be an aryl group, and the rest may be an alkyl group or a cycloalkyl group.

  Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, aryldicycloalkylsulfonium compounds, and the like.

  The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.

  The alkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.

  The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.

The aryl group, alkyl group, and cycloalkyl group of R _{201 to} R ₂₀₃ are an alkyl group (for example, having 1 to 15 carbon atoms), a cycloalkyl group (for example, having 3 to 15 carbon atoms), an aryl group (for example, having 6 to 6 carbon atoms). 14), an alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, a phenylthio group or the like may be used as a substituent. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and alkoxy groups having 1 to 12 carbon atoms, most preferably alkyl having 1 to 4 carbon atoms. Group, an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Examples of the non-nucleophilic anion as X ⁻ include a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methyl anion.

  A non-nucleophilic anion is an anion that has an extremely low ability to cause a nucleophilic reaction, and is an anion that can suppress degradation over time due to an intramolecular nucleophilic reaction. This improves the temporal stability of the resist.

  Examples of the sulfonate anion include an aliphatic sulfonate anion, an aromatic sulfonate anion, and a camphor sulfonate anion.

  Examples of the carboxylate anion include an aliphatic carboxylate anion, an aromatic carboxylate anion, and an aralkylcarboxylate anion.

  Examples of the aliphatic group in the aliphatic sulfonate anion include, for example, an alkyl group having 1 to 30 carbon atoms, specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, sec- Butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl And an eicosyl group and a cycloalkyl group having 3 to 30 carbon atoms, specifically, a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornyl group, a boronyl group, and the like.

  The aromatic group in the aromatic sulfonate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

  The alkyl group, cycloalkyl group, and aryl group in the aliphatic sulfonate anion and aromatic sulfonate anion may have a substituent.

  Examples of such substituents include nitro groups, halogen atoms (fluorine atoms, chlorine atoms, bromine atoms, iodine atoms), carboxyl groups, hydroxyl groups, amino groups, cyano groups, and alkoxy groups (preferably having 1 to 5 carbon atoms). ), A cycloalkyl group (preferably 3 to 15 carbon atoms), an aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably 2 to 7 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms). ), An alkoxycarbonyloxy group (preferably having 2 to 7 carbon atoms), an alkylthio group (preferably having 1 to 15 carbon atoms), and the like. About the aryl group and ring structure which each group has, an alkyl group (preferably C1-C15) can further be mentioned as a substituent.

  Examples of the aliphatic group in the aliphatic carboxylate anion include those similar to the aliphatic group in the aliphatic sulfonate anion.

  Examples of the aromatic group in the aromatic carboxylate anion include the same aromatic groups as in the aromatic sulfonate anion.

  The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 6 to 12 carbon atoms, such as a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylmethyl group.

  The aliphatic group, aromatic group and aralkyl group in the aliphatic carboxylate anion, aromatic carboxylate anion and aralkylcarboxylate anion may have a substituent. Examples of the substituent include aliphatic sulfonic acid The same halogen atom, alkyl group, cycloalkyl group, alkoxy group, alkylthio group and the like as in the anion can be exemplified.

  Examples of the sulfonylimide anion include saccharin anion.

  The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methyl anion is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, An isobutyl group, a sec-butyl group, a pentyl group, a neopentyl group, and the like can be given. These alkyl groups may have a substituent, and examples of the substituent include a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, an alkylthio group, and the like, which are substituted with a fluorine atom. Alkyl groups are preferred.

  Examples of other non-nucleophilic anions include fluorinated phosphorus, fluorinated boron, and fluorinated antimony.

Examples of the non-nucleophilic anion of X ⁻ include an aliphatic sulfonate anion in which the α-position of the sulfonic acid is substituted with a fluorine atom, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group. A bis (alkylsulfonyl) imide anion substituted with a fluorine atom and a tris (alkylsulfonyl) methide anion wherein an alkyl group is substituted with a fluorine atom are preferred. The non-nucleophilic anion is particularly preferably a perfluoroaliphatic sulfonic acid anion having 4 to 8 carbon atoms, an aromatic sulfonic acid anion having a fluorine atom, most preferably a nonafluorobutanesulfonic acid anion, a perfluorooctanesulfonic acid anion, It is a pentafluorobenzenesulfonic acid anion and 3,5-bis (trifluoromethyl) benzenesulfonic acid anion.

Next, the compound (Z1-2) will be described.
The compound (Z1-2) is a compound when R _{201 to} R ₂₀₃ in the general formula (ZI) each independently represents an organic group not containing an aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear, branched, cyclic 2-oxoalkyl group, or an alkoxycarbonylmethyl group, most preferably Is a linear, branched 2-oxoalkyl group.

The alkyl group as R _{201 to} R ₂₀₃ may be either linear or branched, and is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, such as a methyl group, an ethyl group, or a propyl group. Butyl group, pentyl group and the like. More preferable examples of the alkyl group include a 2-linear or branched oxoalkyl group and an alkoxycarbonylmethyl group.

The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably a cycloalkyl group having 3 to 10 carbon atoms, e.g., cyclopentyl, cyclohexyl group and a norbornyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

  The 2-oxoalkyl group may be linear, branched or cyclic, and preferably includes a group having> C = O at the 2-position of the above alkyl group or cycloalkyl group.

  The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, butyl group, pentyl group).

R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

Two members out of R _{201 to} R ₂₀₃ may combine to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

  The compound (Z1-3) is a compound represented by the following general formula (Z1-3), and is a compound having a phenacylsulfonium salt structure.

R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or a halogen atom.
R _6c and R _7c represent a hydrogen atom, an alkyl group, or a cycloalkyl group.
Rx and Ry each independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.

Any two or more of R _{1c to} R _5c , and R _x and R _y may be bonded to each other to form a ring structure, and this ring structure includes an oxygen atom, a sulfur atom, an ester bond, and an amide bond. May be included.

Zc ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of X ^{− in} formula (ZI).

The alkyl group as R _{1c to} R _7c is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, A linear or branched pentyl group can be exemplified.

The cycloalkyl group as R _{1c to} R _7c is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopentyl group and a cyclohexyl group.

The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).

Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _{1c to} R _5c is 2 ~ 15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group and cycloalkyl group as R _x and R _y include the same alkyl groups and cycloalkyl groups as R _{1c to} R _{7c, such} as a 2-oxoalkyl group and a 2-oxocycloalkyl group. An alkoxycarbonylmethyl group is more preferable.

Examples of the 2-oxoalkyl group and 2-oxocycloalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .

Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _{1c to} R _5c .

Examples of the group formed by combining R _x and R _y include a butylene group and a pentylene group.

R _x and R _y are preferably an alkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more.

In formula (ZII), (ZIII), R 204 ~R 207 each independently represents an aryl group, an alkyl group or a cycloalkyl group.

Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group.

The alkyl group as R ₂₀₄ to R ₂₀₇ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group).

The cycloalkyl group as R ₂₀₄ to R ₂₀₇ is preferably a cycloalkyl group having 3 to 10 carbon atoms, e.g., cyclopentyl, cyclohexyl group and a norbornyl group.

The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (e.g., 6 carbon atoms 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.

X ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ^{− in} formula (ZI).

  Preferred examples of the acid generator include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI).

In general formulas (ZIV) to (ZVI), Ar ₃ and Ar ₄ each independently represents an aryl group.

R ₂₀₆ , R ₂₀₇ and R ₂₀₈ are an alkyl group, a cycloalkyl group or an aryl group, and these are the same as the alkyl group, cycloalkyl group or aryl group as R _{204 to} R ₂₀₇ .
A represents an alkylene group, an alkenylene group or an arylene group.

  Among the acid generators, compounds represented by the general formulas (ZI) to (ZIII) are more preferable.

Particularly preferred as the acid generator in the present invention is one represented by the following general formula (I).

In general formula (I),
R ₁ represents an alkyl group, an alicyclic hydrocarbon group, a hydroxyl group, a carboxyl group, an alkoxy group or a halogen atom.
y represents 0 or an integer of 1 to 5 independently of each other. When y is an integer of 2 or more, two or more R1s may be the same or different.
Q ₁ represents an alkyl group substituted with a fluorine atom, a cycloalkyl group substituted with a fluorine atom, an aryl group substituted with a fluorine atom or an aryl group substituted with a fluorinated alkyl group.

As the alkyl group for R1, a linear or branched alkyl group having 1 to 15 carbon atoms is preferable, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, and the like. Can be mentioned.
Examples of the alicyclic hydrocarbon group for R1 include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, an adamantyl group, and the like.
Examples of the alkyl group substituted with the fluorine atom of Q ₁ include, for example, —CF ₃ , —C ₂ F ₅ , —n—C ₃ F ₇ , —CF (CF ₃ ) ₂ , —CH (CF ₃ ) ₂ , _{-CF 2 (CH 2) 3 CH} 3, - (CF 2) 2 OCF 2 CF 3, - (CF 2) 2 O (CH 2) 3 CH 3, - (CF 2) 2 O (CH 2) 13 CH ₃ , -n-C ₄ F ₉ , -t-C ₄ F ₉ , -CF [(CF ₂ ) ₃ CF ₃ ] ₂ , -C [(CF ₂ ) ₃ CF ₃ ] ₃ ,-(CF ₂ ) _{4 O (CH 2) 17 CH 3} , -n-C 8 F 17, -n-C 11 F 23, - (CF 2) such as _{2 O (CF 2) 2 (} CH 2) 3 CH 3 and the like.
Examples of the aryl group substituted with the fluorine atom of Q ₁ include 2,3,4,5,6-pentafluorophenyl group, 2,3,4-trifluorophenyl group, 2,4-difluorophenyl group, 4-fluorophenyl group, 4-undecanyloxy-2,3,5,6-tetrafluorophenyl group and the like can be mentioned.
Examples of the aryl group substituted with the fluorinated alkyl group of Q ₁ include, for example, 3-trifluoromethylphenyl group, 3,5-bis (trifluoromethyl) phenyl group, 4-trifluoromethylphenyl group, 4-n -Nonafluorobutylphenyl group etc. are mention | raise | lifted.

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation, examples of particularly preferable compounds are listed below.

An acid generator can be used individually by 1 type or in combination of 2 or more types.
The content of the acid generator in the resist composition for immersion exposure is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and still more preferably, based on the total solid content of the resist composition. Is 1-7 mass%.

(C) A dissolution inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as a “dissolution inhibiting compound”) that is decomposed by the action of an acid to increase the solubility in an alkaline developer.
The resist composition for immersion exposure of the present invention contains a dissolution inhibiting compound (hereinafter also referred to as “dissolution inhibitor”) having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer. It is preferable to do.
The dissolution inhibitor contains an acid-decomposable group such as a cholic acid derivative containing an acid-decomposable group described in Proceedingof SPIE, 2724,355 (1996) so as not to lower the permeability of 220 nm or less. Alicyclic or aliphatic compounds are preferred. Examples of the acid-decomposable group and alicyclic structure are the same as those described for the resin as the component (A).
The molecular weight of the dissolution inhibitor in the present invention is 3000 or less, preferably 300 to 3000, and more preferably 500 to 2500.

  The addition amount of the dissolution inhibitor is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, based on the total solid content of the resist composition for immersion exposure.

  Although the specific example of a dissolution inhibitor is shown below, it is not limited to these.

(D) Basic compound The resist composition for immersion exposure according to the present invention preferably further contains a basic compound. As the basic compound, for example, a nitrogen-containing basic compound, a basic ammonium salt, a basic sulfonium salt, a basic iodonium salt, or the like may be used as long as it does not deteriorate sublimation or resist performance.

  The basic compound is a component having an action of controlling a diffusion phenomenon in a resist film of an acid generated from an acid generator by exposure and suppressing an undesirable chemical reaction in a non-exposed region. By compounding such a basic compound, the storage stability of the resist composition for immersion exposure that can control the diffusion phenomenon of the acid generated from the acid generator upon exposure in the resist film is improved, and as a resist. In addition, the resolution of the resist pattern can be further improved, and a change in the line width of the resist pattern due to fluctuations in the holding time (PED) from exposure to development processing can be suppressed, and a composition having excellent process stability can be obtained.

  Examples of the nitrogen-containing basic compound include primary, secondary and tertiary aliphatic amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxy group, and compounds having a sulfonyl group. Examples thereof include nitrogen compounds, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amide derivatives, imide derivatives, and nitrogen-containing compounds having a cyano group.

  As aliphatic amines, methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, pentylamine, tert-amylamine, cyclopentylamine, hexylamine, cyclohexylamine, Heptylamine, octylamine, nonylamine, decylamine, dodecylamine, cetylamine, methylenediamine, ethylenediamine, tetraethylenepentamine, dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, diisobutylamine, di -Sec-butylamine, dipentylamine, dicyclopentylamine, dihexylamine, dicyclohexylamine, diheptylamine , Dioctylamine, dinonylamine, didecylamine, didodecylamine, dicetylamine, N, N-dimethylmethylenediamine, N, N-dimethylethylenediamine, N, N-dimethyltetraethylenepentamine, trimethylamine, triethylamine, tri-n-propylamine , Triisopropylamine, tri-n-butylamine, triisobutylamine, tri-sec-butylamine, tripentylamine, tricyclopentylamine, trihexylamine, tricyclohexylamine, triheptylamine, trioctylamine, trinonylamine, tri Decylamine, tridodecylamine, tricetylamine, N, N, N ′, N′-tetramethylmethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, N, N N ', N'-tetramethyl-tetraethylenepentamine, dimethylethylamine, methylethylpropylamine, benzylamine, phenethylamine, benzyldimethylamine, and the like.

  Aromatic amines and heterocyclic amines include aniline derivatives such as aniline, N-methylaniline, N-ethylaniline, N-propylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, ethylaniline, propylaniline, trimethylaniline, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline, 2,6-dinitroaniline, 3,5-dinitroaniline, N, N-dimethyltoluidine, etc.), diphenyl (p-tolyl) amine, methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, pyrrole derivatives (eg pyrrole, 2H-pyrrole, 1-methylpyrrole, 2,4 -Dimethylpyro , 2,5-dimethylpyrrole, N-methylpyrrole, etc.), oxazole derivatives (eg oxazole, isoxazole etc.), thiazole derivatives (eg thiazole, isothiazole etc.), imidazole derivatives (eg imidazole, 4-methylimidazole, 4 -Methyl-2-phenylimidazole, etc.), pyrazole derivatives, furazane derivatives, pyrroline derivatives (eg pyrroline, 2-methyl-1-pyrroline etc.), pyrrolidine derivatives (eg pyrrolidine, N-methylpyrrolidine, pyrrolidinone, N-methylpyrrolidone etc.) ), Imidazoline derivatives, imidazolidine derivatives, pyridine derivatives (eg pyridine, methylpyridine, ethylpyridine, propylpyridine, butylpyridine, 4- (1-butylpentyl) pyridine, dimethylpyridine) Trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, 4-tert-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 1-methyl-2-pyridone, 4- Pyrrolidinopyridine, 1-methyl-4-phenylpyridine, 2- (1-ethylpropyl) pyridine, aminopyridine, dimethylaminopyridine, etc.), pyridazine derivatives, pyrimidine derivatives, pyrazine derivatives, pyrazoline derivatives, pyrazolidine derivatives, piperidine derivatives, Piperazine derivatives, morpholine derivatives, indole derivatives, isoindole derivatives, 1H-indazole derivatives, indoline derivatives, quinoline derivatives (eg quinoline, 3-quinolinecarbonitrile) Etc.), isoquinoline derivatives, cinnoline derivatives, quinazoline derivatives, quinoxaline derivatives, phthalazine derivatives, purine derivatives, pteridine derivatives, carbazole derivatives, phenanthridine derivatives, acridine derivatives, phenazine derivatives, 1,10-phenanthroline derivatives, adenine derivatives, adenosine derivatives Guanine derivatives, guanosine derivatives, uracil derivatives, uridine derivatives and the like.

  Examples of the nitrogen-containing compound having a carboxy group include aminobenzoic acid, indolecarboxylic acid, amino acid derivatives (for example, nicotinic acid, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, glycylleucine, leucine, methionine, phenylalanine. , Threonine, lysine, 3-aminopyrazine-2-carboxylic acid, methoxyalanine) and the like.

  Examples of the nitrogen-containing compound having a sulfonyl group include 3-pyridinesulfonic acid and pyridinium p-toluenesulfonate.

  Examples of the nitrogen-containing compound having a hydroxyl group include 2-hydroxypyridine, aminocresol, 2,4-quinolinediol, 3-indolemethanol hydrate, monoethanolamine, diethanolamine, triethanolamine, N-ethyldiethanolamine, N, N- Diethylethanolamine, triisopropanolamine, 2,2′-iminodiethanol, 2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol, 4- (2-hydroxyethyl) morpholine, 2- ( 2-hydroxyethyl) pyridine, 1- (2-hydroxyethyl) piperazine, 1- [2- (2-hydroxyethoxy) ethyl] piperazine, piperidineethanol, 1- (2-hydroxyethyl) pyrrolidine, 1- (2- Hydroxyethyl ) -2-pyrrolidinone, 3-piperidino-1,2-propanediol, 3-pyrrolidino-1,2-propanediol, 8-hydroxyeurolidine, 3-quinuclidinol, 3-tropanol, 1-methyl-2 -Pyrrolidine ethanol, 1-aziridine ethanol, N- (2-hydroxyethyl) phthalimide, N- (2-hydroxyethyl) isonicotinamide and the like are exemplified.

  Examples of amide derivatives include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide and the like.

  Examples of imide derivatives include phthalimide, succinimide, maleimide and the like.

  Specific examples of the nitrogen-containing compound having a cyano group include 3- (diethylamino) propiononitrile, N, N-bis (2-hydroxyethyl) -3-aminopropiononitrile, N, N-bis (2- Acetoxyethyl) -3-aminopropiononitrile, N, N-bis (2-formyloxyethyl) -3-aminopropiononitrile, N, N-bis (2-methoxyethyl) -3-aminopropiononitrile, N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropiononitrile, methyl N- (2-cyanoethyl) -N- (2-methoxyethyl) -3-aminopropionate, N- (2 -Cyanoethyl) -N- (2-hydroxyethyl) -3-aminopropionic acid methyl, N- (2-acetoxyethyl) -N- (2-cyanoethyl) Methyl 3-aminopropionate, N- (2-cyanoethyl) -N-ethyl-3-aminopropiononitrile, N- (2-cyanoethyl) -N- (2-hydroxyethyl) -3-aminopropiononitrile, N- (2-acetoxyethyl) -N- (2-cyanoethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (2-formyloxyethyl) -3-aminopropiononitrile, N -(2-cyanoethyl) -N- (2-methoxyethyl) -3-aminopropiononitrile, N (2-cyanoethyl) -N- [2- (methoxymethoxy) ethyl] -3-aminopropiononitrile, N -(2-cyanoethyl) -N- (3-hydroxy-1-propyl) -3-aminopropiononitrile, N- (3-acetoxy-1-propionitrile ) -N- (2-cyanoethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (3-formyloxy-1-propyl) -3-aminopropiononitrile, N- (2- Cyanoethyl) -N-tetrahydrofurfuryl-3-aminopropiononitrile, N, N-bis (2-cyanoethyl) -3-aminopropiononitrile, diethylaminoacetonitrile, N, N-bis (2-hydroxyethyl) aminoacetonitrile N, N-bis (2-acetoxyethyl) aminoacetonitrile, N, N-bis (2-formyloxyethyl) aminoacetonitrile, N, N-bis (2-methoxyethyl) aminoacetonitrile, N, N-bis [ 2- (methoxymethoxy) ethyl] aminoacetonitrile, N-cyanomethyl-N- (2- Methoxyethyl) -3-aminopropionate methyl, N-cyanomethyl-N- (2-hydroxyethyl) -3-aminopropionate methyl, N- (2-acetoxyethyl) -N-cyanomethyl-3-aminopropionate methyl N-cyanomethyl-N- (2-hydroxyethyl) aminoacetonitrile, N- (2-acetoxyethyl) -N- (cyanomethyl) aminoacetonitrile, N-cyanomethyl-N- (2-formyloxyethyl) aminoacetonitrile, N -Cyanomethyl-N- (2-methoxyethyl) aminoacetonitrile, N-cyanomethyl-N- [2- (methoxymethoxy) ethyl] aminoacetonitrile, N- (cyanomethyl) -N- (3-hydroxy-1-propyl) amino Acetonitrile, N- (3-acetoxy-1- (Lopyl) -N- (cyanomethyl) aminoacetonitrile, N-cyanomethyl-N- (3-formyloxy-1-propyl) aminoacetonitrile, N, N-bis (cyanomethyl) aminoacetonitrile, 1-pyrrolidinepropiononitrile, 1- Piperidine propiononitrile, 4-morpholine propiononitrile, 1-pyrrolidine acetonitrile, 1-piperidine acetonitrile, 4-morpholine acetonitrile, cyanomethyl 3-diethylaminopropionate, N, N-bis (2-hydroxyethyl) -3-aminopropion Cyanomethyl acid, cyanomethyl N, N-bis (2-acetoxyethyl) -3-aminopropionate, cyanomethyl N, N-bis (2-formyloxyethyl) -3-aminopropionate, N, N-bis (2- Me Xylethyl) -3-aminopropionate cyanomethyl, N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropionate cyanomethyl, 3-diethylaminopropionic acid (2-cyanoethyl), N, N-bis (2 -Hydroxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis (2-acetoxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis (2-formyloxyethyl) ) -3-Aminopropionic acid (2-cyanoethyl), N, N-bis (2-methoxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropionic acid (2-cyanoethyl), cyanomethyl 1-pyrrolidinepropionate, 1-piperidine pro Examples include cyanomethyl pionate, cyanomethyl 4-morpholine propionate, 1-pyrrolidinepropionic acid (2-cyanoethyl), 1-piperidinepropionic acid (2-cyanoethyl), 4-morpholine propionic acid (2-cyanoethyl).

  As the nitrogen-containing basic compound, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,4-diazabicyclo [ 2.2.2] Octane, 4-dimethylaminopyridine, 1-naphthylamine, piperidines, hexamethylenetetramine, imidazoles, hydroxypyridines, pyridines, anilines, hydroxyalkylanilines, 4,4′-diaminodiphenyl ether , Pyridinium p-toluenesulfonate, 2,4,6-trimethylpyridinium p-toluenesulfonate, tetramethylammonium p-toluenesulfonate, tetrabutylammonium lactate, triethylamine, tributylamine, tripentylamine, tri-n-octylami , Tri-i-octylamine, tris (ethylhexyl) amine, tridecylamine, tridodecylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, Tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, cyclohexyldimethylamine, methyldicyclohexylamine, ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, Tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) ) Propane, 2- (3- Aminophenyl) -2- (4-aminophenyl) propane, 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) Propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, bis (2- Tri (cyclo) alkylamines such as dimethylaminoethyl) ether, bis (2-diethylaminoethyl) ether, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, tricyclohexylamine, aniline, N -Methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-ni Roaniline, diphenylamine, triphenylamine, naphthylamine, aromatic amines such as 2,6-diisopropylaniline, polyethyleneimine, polyallylamine, 2-dimethylaminoethylacrylamide polymer, Nt-butoxycarbonyldi-n-octyl Amine, Nt-butoxycarbonyldi-n-nonylamine, Nt-butoxycarbonyldi-n-decylamine, Nt-butoxycarbonyldicyclohexylamine, Nt-butoxycarbonyl-1-adamantylamine, Nt -Butoxycarbonyl-N-methyl-1-adamantylamine, N, N-di-t-butoxycarbonyl-1-adamantylamine, N, N-di-t-butoxycarbonyl-N-methyl-1-adamantylamine, N -T-Butoxyca Bonyl-4,4′-diaminodiphenylmethane, N, N′-di-t-butoxycarbonylhexamethylenediamine, N, N, N′N′-tetra-t-butoxycarbonylhexamethylenediamine, N, N′-di -T-butoxycarbonyl-1,7-diaminoheptane, N, N'-di-t-butoxycarbonyl-1,8-diaminooctane, N, N'-di-t-butoxycarbonyl-1,9-diaminononane, N, N′-di-t-butoxycarbonyl-1,10-diaminodecane, N, N′-di-t-butoxycarbonyl-1,12-diaminododecane, N, N′-di-t-butoxycarbonyl- 4,4′-diaminodiphenylmethane, Nt-butoxycarbonylbenzimidazole, Nt-butoxycarbonyl-2-methylbenzimidazole, Nt Butoxycarbonyl-2-phenylbenzimidazole, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone, urea Methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n-butylthiourea, imidazole, 4-methylimidazole, Imidazoles such as 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole, pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine , 4-phenylpyridine, 2-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 4-hydroxyquinoline, 8-oxyquinoline, acridine and other pyridines, piperazine, 1- (2- Piperazines such as hydroxyethyl) piperazine, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, 3-piperidino-1,2-propanediol, morpholine, 4-methylmorpholine, 1,4-dimethylpiperazine, etc. be able to.

  Among these, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,4-diazabicyclo [2.2.2] Octane, 4-dimethylaminopyridine, 1-naphthylamine, piperidine, 4-hydroxypiperidine, 2,2,6,6-tetramethyl-4-hydroxypiperidine, hexamethylenetetramine, imidazoles, hydroxypyridines, pyridines, 4 , 4'-diaminodiphenyl ether, triethylamine, tributylamine, tripentylamine, tri-n-octylamine, tris (ethylhexyl) amine, tridodecylamine, N, N-di-hydroxyethylaniline, N-hydroxyethyl-N- Nitrogen-containing basic compounds such as ethylaniline are particularly preferred. Yes.

In the resist composition for immersion exposure according to the present invention, a basic ammonium salt can be further used as the basic compound. Specific examples of the basic ammonium salt include the following compounds, but are not limited thereto.
Specifically, ammonium hydroxide, ammonium triflate, ammonium pentaflate, ammonium heptaflate, ammonium nonaflate, ammonium undecaflate, ammonium tridecaflate, ammonium pentadecaflate, ammonium methylcarboxylate, ammonium ethylcarboxylate, Ammonium propyl carboxylate, ammonium butyl carboxylate, ammonium heptyl carboxylate, ammonium hexyl carboxylate, ammonium octyl carboxylate, ammonium nonyl carboxylate, ammonium decyl carboxylate, ammonium undecyl carboxylate, ammonium dodecadecyl carboxylate, ammonium salt Decyl carboxylate, ammonium tetradecyl carboxylate, ammonium pentadecyl carboxylate, ammonium hexadecyl carboxylate, ammonium heptadecyl carboxylate, ammonium octadecyl carboxylate and the like.

  Specific examples of ammonium hydroxide include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, and tetraheptyl. Ammonium hydroxide, methyl trioctyl ammonium hydroxide, tetraoctyl ammonium hydroxide, didecyl dimethyl ammonium hydroxide, tetrakisdecyl ammonium hydroxide, dodecyl trimethyl ammonium hydroxide, dodecyl ethyl dimethyl ammonium hydroxide, didodecyl dimethyl ammonium hydroxide, Tridodecylmethylammonium hydro Side, myristylmethylammonium hydroxide, dimethylditetradecylammonium hydroxide, hexadecyltrimethylammonium hydroxide, octadecyltrimethylammonium hydroxide, dimethyldioctadecylammonium hydroxide, tetraoctadecylammonium hydroxide, diallyldimethylammonium hydroxide, (2 -Chloroethyl) -trimethylammonium hydroxide, (2-bromoethyl) trimethylammonium hydroxide, (3-bromopropyl) -trimethylammonium hydroxide, (3-bromopropyl) triethylammonium hydroxide, glycidyltrimethylammonium hydroxide, choline hydroxy (R)-(+)-(3-chloro-2-hydro Cypropyl) trimethylammonium hydroxide, (S)-(−)-(3-chloro-2-hydroxypropyl) -trimethylammonium hydroxide, (3-chloro-2-hydroxypropyl) -trimethylammonium hydroxide, (2- Aminoethyl) -trimethylammonium hydroxide, hexamethonium hydroxide, decamethonium hydroxide, 1-azoniapropellan hydroxide, petronium hydroxide, 2-chloro-1,3-dimethyl-2-imidazolinium hydroxy And 3-ethyl-2-methyl-2-thiazolinium hydroxide.

The basic compound can be used alone or in combination of two or more, and it is more preferable to use two or more.
The amount of the basic compound used is generally 0.001 to 10% by mass, preferably 0.01 to 5% by mass, based on the solid content of the resist composition for immersion exposure, as a total amount.

(E) Surfactant The resist composition for immersion exposure of the present invention preferably further comprises (E) a surfactant, and is a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant, silicon It is more preferable to contain any one of a system surfactant, a surfactant having both a fluorine atom and a silicon atom, or two or more thereof.

When the resist composition for immersion exposure of the present invention contains the surfactant (E), adhesion and development defects can be obtained with good sensitivity and resolution when using an exposure light source of 250 nm or less, particularly 220 nm or less. A small resist pattern can be provided.
Examples of the fluorine-based and / or silicon-based surfactant include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.
Examples of commercially available surfactants that can be used include F-top EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189, R08 (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical Co., Ltd.), etc. Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, the surfactant is derived from a fluoroaliphatic compound produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy) (Ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate) copolymer, acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate having C ₈ F ₁₇ groups (or Copolymer of acrylate (or methacrylate), (poly (oxyethylene)) acrylate (or methacrylate), and (poly (oxypropylene)) acrylate (or methacrylate) having a C ₈ F ₁₇ group List union It can be.

  In the present invention, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, etc. Sorbitans such as polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopal Te - DOO, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, may be mentioned polyoxyethylene sorbitan tristearate nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as such.

  In the present invention, a surfactant represented by the following general formula (W) can also be used.

In general formula (W),
R _w represents a hydrogen atom or an alkyl group.
m represents an integer of 1 to 30.
n represents an integer of 0 to 3.
p represents an integer of 0 to 5.

The alkyl group for R _w is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, or a t-butyl group. And a methyl group, an ethyl group, and a propyl group are more preferable.

  In general formula (W), it is more preferable that m is an integer of 1 to 25, n is an integer of 0 to 2, and p is an integer of 0 to 3.

Preferable specific examples of the surfactant represented by the general formula (W) include, for example, PF636 which is a commercially available product (n = 0, m = 6, p = 1, R ₁ = methyl group in the general formula (W)). PF6320 (n = 0, m = 20, p = 1, R ₁ = methyl group), PF656 (n = 1, m = 6, p = 1, R ₁ = methyl group in the general formula (W)), PF6520 (In general formula (W), n = 1, m = 20, p = 1, R ₁ = methyl group) (above, manufactured by OMNOVA) and the like can be mentioned.

  These surfactants may be used alone or in several combinations.

  (E) The amount of the surfactant used is preferably 0.01 to 5% by mass, more preferably 0.1 to 3% by mass, based on the total amount of the resist composition for immersion exposure (excluding the solvent). .

(F) Organic solvent Solvents that can be used when preparing the resist composition by dissolving the above components include, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate ester, alkoxy Examples thereof include alkyl propionate, cyclic lactone having 4 to 10 carbon atoms, monoketone compound having 4 to 10 carbon atoms which may contain a ring, alkylene carbonate, alkyl alkoxyacetate, alkyl pyruvate and the like.

Examples of the alkylene glycol monoalkyl ether carboxylate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl Preferred examples include ether propionate, ethylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate.
Preferred examples of the alkylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether.

Preferred examples of the alkyl lactate include methyl lactate, ethyl lactate, propyl lactate and butyl lactate.
Preferable examples of the alkyl alkoxypropionate include ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, and ethyl 3-methoxypropionate.

  Examples of the cyclic lactone having 4 to 10 carbon atoms include β-propiolactone, β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone, β-methyl-γ-butyrolactone, γ-valerolactone, γ- Caprolactone, γ-octanoic lactone, and α-hydroxy-γ-butyrolactone are preferred.

  Examples of the monoketone compound having 4 to 10 carbon atoms which may contain a ring include 2-butanone, 3-methylbutanone, pinacolone, 2-pentanone, 3-pentanone, 3-methyl-2-pentanone, 4- Methyl-2-pentanone, 2-methyl-3-pentanone, 4,4-dimethyl-2-pentanone, 2,4-dimethyl-3-pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2 -Hexanone, 3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4 -Heptanone, 2-octanone, 3-octanone, 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5- Xen-2-one, 3-penten-2-one, cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone, 2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopenta Non, cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2,2-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone, 2-methylcyclo Preferred are heptanone and 3-methylcycloheptanone.

Preferred examples of the alkylene carbonate include propylene carbonate, vinylene carbonate, ethylene carbonate, and butylene carbonate.
Examples of the alkyl alkoxyacetate include 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2- (2-ethoxyethoxy) ethyl acetate, 3-methoxy-3-methylbutyl acetate, and 1-methoxy-acetate. 2-propyl is preferred.
Preferred examples of the alkyl pyruvate include methyl pyruvate, ethyl pyruvate, and propyl pyruvate.
As a solvent which can be preferably used, a solvent having a boiling point of 130 ° C. or higher under normal temperature and normal pressure can be mentioned. Specifically, cyclopentanone, γ-butyrolactone, cyclohexanone, ethyl lactate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate, ethyl pyruvate, 2-ethoxyethyl acetate, acetic acid -2- (2-ethoxyethoxy) ethyl and propylene carbonate are mentioned.
In the present invention, the above solvents may be used alone or in combination of two or more.

In this invention, you may use the mixed solvent which mixed the solvent which contains a hydroxyl group in a structure, and the solvent which does not contain a hydroxyl group as an organic solvent.
Examples of the solvent containing a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Particularly preferred are propylene glycol monomethyl ether and ethyl lactate.
Examples of the solvent not containing a hydroxyl group include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, and butyl acetate are particularly preferable, and propylene glycol monomethyl ether acetate, ethyl ethoxypropionate. 2-heptanone is most preferred.
The mixing ratio (weight) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60/40. . A mixed solvent containing 50% by weight or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.

(G) Alkali-soluble resin The positive resist composition of the present invention may further contain an acid-decomposable group, (G) a resin that is insoluble in water and soluble in an alkaline developer, This improves the sensitivity.
In the present invention, a novolak resin having a molecular weight of about 1000 to 20000 and a polyhydroxystyrene derivative having a molecular weight of about 3000 to 50000 can be used as such a resin, since these have a large absorption with respect to light of 250 nm or less. It is preferable to use a partly hydrogenated amount or 30% by weight or less of the total resin amount.
A resin containing a carboxyl group as an alkali-soluble group can also be used. The resin containing a carboxyl group preferably has a monocyclic or polycyclic alicyclic hydrocarbon group for improving dry etching resistance. Specifically, a methacrylic acid ester and (meth) acrylic acid copolymer having an alicyclic hydrocarbon structure that does not exhibit acid decomposability, or a (meth) acrylic acid ester having an alicyclic hydrocarbon group having a carboxyl group at the terminal And the like.

(H) Carboxylic acid onium salt Examples of the (H) carboxylic acid onium salt in the present invention include a carboxylic acid sulfonium salt, a carboxylic acid iodonium salt, and a carboxylic acid ammonium salt. In particular, the (H) carboxylic acid onium salt is preferably an iodonium salt or a sulfonium salt. Furthermore, it is preferable that the carboxylate residue of the (H) carboxylic acid onium salt of the present invention does not contain an aromatic group or a carbon-carbon double bond. As a particularly preferable anion moiety, a linear, branched, monocyclic or polycyclic alkylcarboxylic acid anion having 1 to 30 carbon atoms is preferable. More preferably, an anion of a carboxylic acid in which some or all of these alkyl groups are fluorine-substituted is preferable. The alkyl chain may contain an oxygen atom. This ensures transparency with respect to light of 220 nm or less, improves sensitivity and resolution, and improves density dependency and exposure margin.

  Fluoro-substituted carboxylic acid anions include fluoroacetic acid, difluoroacetic acid, trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid, nonafluoropentanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorocyclohexanecarboxylic acid, 2 , 2-bistrifluoromethylpropionic acid anion and the like.

  These (H) carboxylic acid onium salts can be synthesized by reacting sulfonium hydroxide, iodonium hydroxide, ammonium hydroxide and carboxylic acid with silver oxide in a suitable solvent.

  The content of the (H) carboxylic acid onium salt in the composition is suitably 0.1 to 20% by weight, preferably 0.5 to 10% by weight, more preferably 1 to the total solid content of the composition. -7% by weight.

Other Additives In the resist composition for immersion exposure according to the present invention, if necessary, a dye, a plasticizer, a photosensitizer, and a compound that promotes solubility in a developer (for example, phenol having a molecular weight of 1000 or less). A compound, an alicyclic compound having a carboxyl group, or an aliphatic compound).

Such phenolic compounds having a molecular weight of 1000 or less can be obtained by referring to, for example, the methods described in JP-A-4-1222938, JP-A-2-28531, US Pat. No. 4,916,210, European Patent 219294, etc. It can be easily synthesized by those skilled in the art.
Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples thereof include, but are not limited to, dicarboxylic acids.

(how to use)
The resist composition for immersion exposure according to the present invention is used by dissolving the above components in a predetermined organic solvent, preferably the mixed solvent, and applying the solution on a predetermined support as follows.
That is, the resist composition for immersion exposure is applied to a substrate (eg, silicon / silicon dioxide coating) used for the manufacture of precision integrated circuit elements by an appropriate coating method such as a spinner or a coater. 50 to 500 nm). After application, the resist film is washed with immersion water as necessary. The washing time is usually 5 seconds to 5 minutes.
Subsequently, the resist applied by spin or bake is dried to form a resist film, and then exposed through a mask or the like for pattern formation and exposed (immersion exposure) through immersion water. For example, the exposure is performed in a state where the space between the resist film and the optical lens is filled with the immersion liquid. Although an exposure amount can be set suitably, it is 1-100 mJ / cm < ² > normally. After exposure, the resist film is washed with immersion water as necessary. The time is usually 5 seconds to 5 minutes. Subsequently, spin or / and baking is preferably performed, and development and rinsing are performed to obtain a good pattern. The baking temperature is usually 30 to 300 ° C. From the above-mentioned PED point, it is better that the time from the exposure to the baking process is short.
Here, the exposure light is preferably far ultraviolet rays having a wavelength of 250 nm or less, more preferably 220 nm or less. Specific examples include KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-rays, and the like.
Incidentally, it is considered that the change in performance observed when the resist is applied to immersion exposure is derived from the contact of the resist surface with the immersion liquid.

The immersion liquid used for the immersion exposure will be described below.
The immersion liquid is preferably a liquid that is transparent to the exposure wavelength and has a refractive index temperature coefficient as small as possible so as to minimize distortion of the optical image projected onto the resist. In the case of an ArF excimer laser (wavelength: 193 nm), it is preferable to use water from the viewpoints of availability and ease of handling in addition to the above-described viewpoints.
When water is used as the immersion liquid, the surface tension of the water is decreased and the surface activity is increased, so that the resist layer on the wafer is not dissolved and the influence on the optical coating on the lower surface of the lens element can be ignored. An additive (liquid) may be added in a small proportion. The additive is preferably an aliphatic alcohol having a refractive index substantially equal to that of water, and specifically includes methyl alcohol, ethyl alcohol, isopropyl alcohol and the like. By adding an alcohol having a refractive index substantially equal to that of water, even if the alcohol component in water evaporates and the content concentration changes, an advantage that the change in the refractive index of the entire liquid can be made extremely small can be obtained. On the other hand, when an opaque substance or impurities whose refractive index is significantly different from that of water are mixed with respect to 193 nm light, the optical image projected on the resist is distorted. Therefore, distilled water is preferable as the water to be used. Further, pure water filtered through an ion exchange filter or the like may be used.

In order to prevent the resist film from coming into direct contact with the immersion liquid between the resist film formed by the immersion exposure resist of the present invention and the immersion liquid, it is also called an immersion liquid hardly soluble film (hereinafter also referred to as “top coat”). ) May be provided. The necessary functions for the top coat are suitability for application to the upper layer of the resist, radiation, especially transparency to 193 nm, and poor immersion liquid solubility. It is preferable that the top coat is not mixed with the resist and can be uniformly applied to the resist upper layer.
From the viewpoint of 193 nm transparency, the topcoat is preferably a polymer that does not contain an aromatic, and specifically, a hydrocarbon polymer, an acrylate polymer, a polymethacrylic acid, a polyacrylic acid, a polyvinyl ether, a silicon-containing polymer, And fluorine-containing polymers.
When peeling the top coat, a developer may be used, or a separate release agent may be used. As the release agent, a solvent having a small penetration into the resist is preferable. It is preferable that the peeling process can be performed with an alkali developer in that the peeling process can be performed simultaneously with the resist development process. From the viewpoint of peeling with an alkaline developer, the topcoat is preferably acidic, but may be neutral or alkaline from the viewpoint of non-intermixability with the resist.
The resolution is improved when there is no difference in refractive index between the topcoat and the immersion liquid. When the exposure light source is an ArF excimer laser (wavelength: 193 nm), it is preferable to use water as the immersion liquid, so that the top coat for ArF immersion exposure is close to the refractive index of water (1.44). Is preferred. A thin film is more preferable from the viewpoint of transparency and refractive index.

In the development process, a developer is used as follows. Examples of the developer for the resist composition for immersion exposure include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, ethylamine, and n-propylamine. Secondary amines such as amines, diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxy Alkaline aqueous solutions such as quaternary ammonium salts such as pyrrole and cyclic amines such as pyrrole and pihelidine can be used.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline aqueous solution.
As the rinsing liquid, pure water can be used, and an appropriate amount of a surfactant can be added.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.

  Further, after the development process or the rinsing process, a process of removing the developer or the rinsing liquid adhering to the pattern with a supercritical fluid can be performed.

EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, the content of this invention is not limited by this.
Examples 7, 10, 14, 15, 22-27, 44, and 45 shall be read as “reference examples”.

1. Synthesis of fluorine-containing resin (1) Mevalonic lactone acrylate, {6- (3,3,3-trifluoro-2-hydroxy-2-trifluoromethyl-propyl) -bicyclo [2.2.1] hept-2- Yl} methacrylate and 2-ethyl-2-adamantyl methacrylate were charged at a ratio of 40/20/40 and dissolved in tetrahydrofuran to prepare 100 mL of a 20% solid content solution. To this solution was added 2 mol% of Wako Pure Chemicals V-65 and 4 mol% of mercaptoethanol as a polymerization initiator, and this was added dropwise to 10 mL of tetrahydrofuran heated to 60 ° C. over 2 hours in a nitrogen atmosphere. After completion of dropping, the reaction solution was heated and stirred for 6 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and crystallized and precipitated white powder was recovered in 3 L of methanol. ^The polymer composition ratio determined from ¹³ C-NMR was 46/54. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 9800, and dispersion degree was 2.53. Thereafter, fluorine-containing resins (2) to (20) and a comparative resin (C1) were synthesized in the same manner.
The structures and weight average molecular weights of the fluorine-containing resins (1) to (20) and the comparative resin (C1) are collectively shown below.

2. Preparation of resist compositions 1 to 33 and a resist composition as a comparative example <Resist adjustment>
The components shown in Table 1 below were dissolved in a solvent to prepare a solution having a solid content concentration of 6% by mass, and this was filtered through a 0.1 μm polyethylene filter to prepare a positive resist solution.

3. Evaluation [Evaluation of acid elution amount]
The prepared resist composition was applied to an 8-inch silicon wafer and baked at 115 ° C. for 60 seconds to form a 150 nm resist film. After exposing this resist film with an exposure machine having a wavelength of 193 nm at an entire surface of 50 mJ / cm ² , 5 ml of pure water deionized using an ultrapure water production apparatus (Milli-QJr., Manufactured by Nihon Millipore) It was dripped in. Water was placed on the resist film for 50 seconds, the water was collected, and the acid elution concentration was quantified by LC-MS.
LC device: Waters 2695
MS equipment: esquire 3000plus from Bruker Daltonics
The MS detection intensity of ionic species having a mass of 299 (corresponding to nonaflate anion) was measured with the LC-MS apparatus, and the elution amount of nonafluorobutanesulfonic acid was calculated. Similarly, the MS detection intensity of an ionic species having a mass of 413 (corresponding to 4-dodecyloxy-2,3,5,6-tetrafluorobenzenesulfonate anion) was measured, and 4-dodecyloxy-2,3,5,6 was measured. -The elution amount of tetrafluorobenzenesulfonic acid was calculated.

[Sensitivity fluctuation rate evaluation]
An antireflection film (ARC25, manufactured by Brewer Science Co., Ltd.) was uniformly applied on the silicon substrate by a spin coater at 600 angstroms and dried at 190 ° C. for 240 seconds.
Next, each positive resist solution was applied by a spin coater, and the wafer was heated and dried at 115 ° C. for 60 seconds to form a 0.25 μm resist film. For this resist film, a sensitivity of 193 nm exposure was evaluated (dry sensitivity) using a 193 nm laser exposure / dissolution behavior analyzer VUVES-4500 (manufactured by RISOTEC Japan). Next, after a resist film was formed on a silicon substrate by the same method, sensitivity by 193 nm exposure was evaluated using a liquid immersion exposure / dissolution behavior analyzer MODEL IMES-5500 (manufactured by RISOTEC JAPAN) (wet sensitivity).
Sensitivity here refers to a wafer after exposure to heat and drying at 120 ° C. for 60 seconds, followed by development at 23 ° C. for 30 seconds using an aqueous 2.38 mass% tetramethylammonium hydroxide solution, and then with pure water for 30 seconds. When the film thickness is measured after rinsing and drying, it indicates the minimum exposure amount at which the film thickness becomes zero.
The sensitivity change rate was measured by the following formula, and used as an index of compatibility (compatibility) of dry exposure / wet exposure.
Sensitivity change rate (%) = (wet sensitivity-dry sensitivity) / dry sensitivity x 100
Table 1 summarizes the resist compositions used in the evaluation and the evaluation results.

  Hereinafter, the abbreviations in each table are as follows.

N-1: N, N-dibutylaniline N-2: N, N-dipropylaniline N-3: N, N-dihydroxyethylaniline N-4: 2,4,5-triphenylimidazole N-5: 2 , 6-Diisopropylaniline N-6: Hydroxyantipyrine

W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Mega W-2; Fuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon-based)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)
W-4: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)
W-5: PF-6520 (made by OMNOVA)

SL-1: cyclopentanone SL-2: cyclohexanone SL-3: 2-methylcyclohexanone SL-4: propylene glycol monomethyl ether acetate SL-5: ethyl lactate SL-6: propylene glycol monomethyl ether SL-7: 2-heptanone SL-8: γ-butyrolactone SL-9: Propylene carbonate

I-1: t-butyl lithocholic acid I-2: t-butyl adamantanecarboxylate In each table, the ratio when a plurality of resins or solvents are used is a mass ratio.

  From Examples 1 to 49 in Table 2 above, it can be seen that the resist composition of the present invention has little acid elution into the immersion liquid and a small rate of change in sensitivity with dry exposure. That is, in the comparative example, the amount of nonafluorobutanesulfonic acid eluted into the immersion water is large, and the sensitivity fluctuation rate at the time of dry exposure is large. Compared with this, as shown in Example 1, the resist of the present invention By using the composition, it can be seen that there is little elution of the acid into the immersion liquid at the time of immersion exposure and the sensitivity fluctuation rate is also small.

Claims (10)

(A) Resin having at least one repeating unit represented by the following general formula (IIa) and having increased solubility in an alkali developer by the action of an acid (provided that the resin is represented by the following general formula (3)) (Excluding resins having a repeating unit of a fluorine cyclic compound and resins having a repeating unit represented by the following general formula (Ia)) and (B) a compound that generates an acid upon irradiation with actinic rays or radiation,
A positive resist composition for immersion exposure, comprising:

In general formula (IIa),
R _{x1 to} R _x3 each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or —L ₃ —C (R _f1 ) (R _f2 ) Ra.
R _f1 and R _f2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _f1 and R _f2 is a fluorine atom or a fluoroalkyl group.
Ra represents a hydrogen atom or a hydroxyl group.
L ₃ represents a single bond, an alkylene group, —CH ₂ —O— or —CH ₂ —COO—.
R ₁ and R _m each independently represents a hydrogen atom or an alkyl group.
Z ₁ represents a single bond, an alkylene group, a cycloalkylene group or an arylene group.
L ₁ represents a single bond or a divalent linking group.
n and q each independently represents 0 or 1.
r represents an integer of 1 to 6.

In general formula (3),
R ₁ b is a cyclic alkyl group having 1 to 25 carbon atoms, a cyclic alkenyl group, a cyclic alkynyl group, an aryl group, or a heterocyclic group, and includes a fluorine atom, oxygen atom, sulfur atom, nitrogen atom, carbon- An atomic group containing a carbon double bond may be included.
R _{2 to} R ₇ are each a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group having 1 to 25 carbon atoms, and includes a fluorine atom, an oxygen atom, a sulfur atom, a nitrogen atom, and a carbon-carbon atom. An atomic group containing a double bond may be included.
R ₈ is a carbonyl group or a methylene group, or a single bond.

Where
R ¹ represents a hydrogen atom, a methyl group, or —CH ₂ CO ₂ R ¹⁴ .
R ² represents a hydrogen atom, a methyl group, or —CO ₂ R ¹⁴ .
R ³ represents a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms.
R ^{4 to} R ⁹ , R ¹² and R ¹³ each independently represent a hydrogen atom or a monovalent hydrocarbon group which may contain a C 1-15 hetero atom, and R ¹⁰ and R ¹¹ represent a hydrogen atom. . Alternatively, R ⁴ and R ^5, R ⁶ and R ^8, R ⁶ and R ^9, R ⁷ and R ^9, R ⁷ and R ^13, R ⁸ and R ^12, R ¹⁰ and R ^11, R ¹¹ and R ¹² are The divalent hydrocarbon group which may form the ring mutually and may contain the C1-C15 hetero atom in that case is shown. R ⁴ and R ¹³ , R ¹⁰ and R ¹³ , and R ⁶ and R ⁸ may be bonded to adjacent carbons without any intervention to form a double bond.
R ¹⁴ represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms. The general formula (1a) also represents a mirror image. (A) Resin having at least one repeating unit represented by the following general formula (IIb) and having increased solubility in an alkali developer by the action of an acid (however, the repeating represented by the following general formula (Ia)) Excluding resins with units) and
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
A positive resist composition for immersion exposure, comprising:

In general formula (IIb),
R _x1 ~ R _x3 Each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group or -L. _Three -C (R _f1 ) (R _f2 ) Represents Ra.
  R _f1 , R _f2 Each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, R _f1 , R _f2 At least one of these is a fluorine atom or a fluoroalkyl group.
  Ra represents a hydrogen atom or a hydroxyl group.
  L _Three Is a single bond, an alkylene group, -CH ₂ -O- or -CH ₂ -COO- is represented.
  R _l , R _m Each independently represents a hydrogen atom or an alkyl group.
  Z _1b Represents a polycyclic cycloalkylene group.
  L ₁ Represents a single bond or a divalent linking group.
  n and q each independently represents 0 or 1.
  r represents an integer of 1 to 6.

Where
R ¹ Is a hydrogen atom, a methyl group, -CH ₂ CO ₂ R ¹⁴ Indicates.
R ² Is a hydrogen atom, a methyl group, -CO ₂ R ¹⁴ Indicates.
R ^Three Represents a linear, branched, or cyclic alkyl group having 1 to 8 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms.
R ^Four ~ R ⁹ , R ¹² , R ¹³ Each independently represents a hydrogen atom or a monovalent hydrocarbon group which may contain a hetero atom having 1 to 15 carbon atoms; ^Ten , R ¹¹ Represents a hydrogen atom. Or R ^Four And R ^Five , R ⁶ And R ⁸ , R ⁶ And R ⁹ , R ⁷ And R ⁹ , R ⁷ And R ¹³ , R ⁸ And R ¹² , R ^Ten And R ¹¹ , R ¹¹ And R ¹² May form a ring with each other, and in this case, represents a divalent hydrocarbon group that may contain a hetero atom having 1 to 15 carbon atoms. Also R ^Four And R ¹³ , R ^Ten And R ¹³ , R ⁶ And R ⁸ May be bonded to each other adjacent to carbons without intervening to form a double bond.
R ¹⁴ Represents a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms. The general formula (1a) also represents a mirror image. (A) a resin having at least one repeating unit selected from the group of the following general formulas (IV) to (IX) and having increased solubility in an alkali developer by the action of an acid;
(B) a compound that generates an acid upon irradiation with actinic rays or radiation,
A positive resist composition for immersion exposure, comprising:

X ₁ Represents an oxygen atom or a sulfur atom.
  X ₂ Represents a methylene group, an oxygen atom or a sulfur atom.
  Rx represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, an alkyl group, or -L _Three -Ra is represented. L _Three Is an alkylene group, -CH ₂ O- or -CH ₂ O (C═O) — represents Ra, and represents a hydroxyl group, a lactone group, or a fluoroalkyl group.
  Rf, Rf ₁ , Rf ₂ Each independently represents a group having at least one fluorine atom. Rf ₁ And Rf ₂ Are connected to each other-(CF ₂ ) N ₁ A ring having-may be formed. n ₁ Represents an integer of 1 or more.
j represents an integer of 1 to 3. The resin of component (A) further has a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pVI). The positive resist composition for immersion exposure according to any one of the above.

Where
R ₁₁ Represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z is necessary to form an alicyclic hydrocarbon group together with a carbon atom. Represents an atomic group.
  R ₁₂ ~ R ₁₆ Each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that R represents ₁₂ ~ R ₁₄ At least one of R or R ₁₅ , R ₁₆ Any of represents an alicyclic hydrocarbon group.
  R ₁₇ ~ R _{twenty one} Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that R represents ₁₇ ~ R _{twenty one} At least one of these represents an alicyclic hydrocarbon group. R ₁₉ , R _{twenty one} Any of represents a C1-C4 linear or branched alkyl group or alicyclic hydrocarbon group.
  R _{twenty two} ~ R _{twenty five} Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that R represents _{twenty two} ~ R _{twenty five} At least one of these represents an alicyclic hydrocarbon group. R _{twenty three} And R _{twenty four} May be bonded to each other to form a ring. The positive resist composition for immersion exposure according to any one of claims 1 to 4, wherein the resin of component (A) further comprises a repeating unit represented by the following general formula (AI).

In general formula (AI),
R _b0 Represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms.
  A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
  B ₂ Represents a group represented by any one of the following general formula (Lc) or general formulas (V-1) to (V-5).


In general formula (Lc),
Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , Re ₁ Each independently represents a hydrogen atom or an optionally substituted alkyl group.
m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In general formulas (V-1) to (V-5),
R _1b ~ R _5b Each independently represents a hydrogen atom or an optionally substituted alkyl group, cycloalkyl group, alkoxy group, alkoxycarbonyl group, alkylsulfonylimino group or alkenyl group. R _1b ~ R _5b Two of these may combine to form a ring. The positive resist composition for immersion exposure according to any one of claims 1 to 5, wherein the resin of component (A) further has a repeating unit represented by the following general formula (AII).

In general formula (AII),
R ₁ c represents a hydrogen atom or a methyl group.
  R ₂ c ~ R _Four c represents a hydrogen atom or a hydroxyl group each independently. However, R ₂ c ~ R _Four At least one of c represents a hydroxyl group. A repeating unit represented by the general formula (IIa), a repeating unit represented by the general formula (IIb), or a repeating unit having a fluorine atom selected from the repeating units selected from the group of the general formulas (IV) to (IX). The positive resist composition for immersion exposure according to any one of claims 1 to 6, wherein the content ratio in the resin (A) is 10 mol% to 30 mol%.   The positive resist composition for immersion exposure according to any one of claims 1 to 7, wherein the positive resist composition is for ArF excimer laser exposure. A pattern forming method comprising: forming a resist film from the resist composition according to claim 1, subjecting the resist film to immersion exposure, and developing.   The pattern forming method according to claim 9, wherein the immersion exposure is exposure with an ArF excimer laser.