JP2010237627A - Active light or radiation sensitive resin composition and pattern forming method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active light or radiation sensitive resin composition which allows formation of a pattern having less water residue defects, bubble defects, and development residue defects and is superior in LWR, and a pattern forming method using this resin composition. <P>SOLUTION: The active light or radiation sensitive resin composition includes a resin (HR) having a recurring unit (a) which has a polycyclic structure in its main chain and has a portion where the polycyclic structure is decomposed by the action of an acid to increase the solubility in an alkaline developer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an actinic ray-sensitive or radiation-sensitive resin composition used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, and other photofabrication lithography processes, and The present invention relates to a pattern forming method using the composition. In particular, the present invention uses an actinic ray-sensitive or radiation-sensitive resin 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 the composition. The present invention relates to a pattern forming method.

  In the present invention, “active light” or “radiation” means, for example, an emission line spectrum of a mercury lamp, far ultraviolet rays represented by excimer laser, extreme ultraviolet rays, X-rays, electron beams, and the like. In the present invention, light means actinic rays or radiation.

With the miniaturization of semiconductor elements, the wavelength of the exposure light source has been shortened and the projection lens has a high numerical aperture (high NA). Currently, there is an exposure machine with NA = 0.84 using an ArF excimer laser having a 193 nm wavelength as a light source. Has been developed. 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
Where 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.

As a technique for increasing the resolution in an optical microscope for higher resolution by further shortening the wavelength, a liquid with a high refractive index (hereinafter also referred to as “immersion liquid”) is conventionally filled between the projection lens and the sample. A so-called immersion method 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 are introduced in Patent Document 1, Patent Document 2, and the like.

  Recent progress in immersion exposure technology has been reported in Non-Patent Documents 1 to 3 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 generally used as the immersion liquid from the viewpoints of handling safety and transmittance and refractive index at 193 nm.

  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. Explaining by 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 upon exposure, and the generated acid is reacted as a reaction catalyst by post exposure baking (PEB). Is used to change an alkali-insoluble group to an alkali-soluble group, and an exposed portion is removed by alkali development.

  The ArF excimer laser (193 nm) resist using this chemical amplification mechanism is currently the mainstream. However, when the chemical amplification resist is applied to immersion exposure, the resist layer comes into contact with the immersion liquid during exposure. It has been pointed out that the layer is denatured and that a component that adversely affects the immersion liquid exudes from the resist layer. For example, Patent Document 3 describes an example in which resist performance is changed by immersing a resist for ArF exposure in water before and after exposure, and points out a problem in immersion exposure. For such problems, for example, Patent Document 4 contains a resin containing silicon or fluorine, and Patent Documents 5 to 7 contain a polymer having a cyclic structure in the main chain. The example which suppresses the exudation to immersion liquid is described by using resin which has an acid-decomposable group.

  In the immersion exposure process, when exposure is performed using a scanning immersion exposure machine, the exposure scan speed must be reduced if the immersion liquid does not move following the movement of the lens. There is concern that it may affect sex. In the case where the immersion liquid is water, it is desirable that the resist film is hydrophobic because the water followability is good.

  Furthermore, in recent years, from the viewpoint of productivity, the exposure scanning speed of the exposure machine has been improved, and further hydrophobicity has become necessary. At that time, if the followability of water is insufficient, water droplets remain during exposure scanning, remain as post-development defects (water remaining defects), and reduce the yield. On the other hand, if the hydrophobicity is too high, air enters in the scanning direction and does not form an image due to a change in the refractive index, and a defect generally called a bubble defect occurs, which may also reduce the yield. It has been known.

  On the other hand, apart from the defects unique to the liquid immersion process, this hydrophobization reduces the wettability of water in the post-development rinsing process and increases the development residue, which is also a factor that reduces the yield. It is known to be.

JP-A-57-153433 JP-A-7-220990 International Publication No. 2004-068242 Pamphlet JP 2006-309245 A Japanese Patent Laid-Open No. 2007-212990 JP 2007-293192 A JP 2007-219144 A

Bulletin of the International Society of Optical Engineering (Proc. SPIE), 2002, 4688, 11 J. et al. Vac. Sci. Tecnol. B 17 (1999) Bulletin of International Society of Optical Engineering (Proc. SPIE), 2000, 3999, 2nd page

  An object of the present invention is to form a pattern with few water residue defects, bubble defects, and development residue defects, and an actinic ray-sensitive or radiation-sensitive resin composition having an excellent LWR, and the composition. It is to provide a pattern forming method used.

As a result of intensive studies to solve the above problems, the present inventor has reached the present invention shown below.
(1) Contains a resin (HR) having a repeating unit (a) having a polycyclic structure in the main chain and having a site where the polycyclic structure is decomposed by the action of an acid to increase the solubility in an alkaline developer An actinic ray-sensitive or radiation-sensitive resin composition characterized by comprising:

  (2) The actinic ray-sensitive or radiation-sensitive resin composition according to (1), wherein the repeating unit (a) contains a fluorine atom.

  (3) The actinic ray-sensitive or radiation-sensitive resin composition according to (1) or (2), wherein the resin (HR) further contains a repeating unit containing a fluorine atom.

(4) The actinic ray-sensitive or radiation-sensitive resin according to any one of (1) to (3), wherein the repeating unit (a) is represented by the following general formula (I): Composition.

In the formula, R ₁ represents a group that is decomposed by the action of an acid.

R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a fluorine atom, an alkyl group, a cycloalkyl group, an alkoxy group, a group containing a carbonyl group, a group containing a carbonyloxy group, a group containing an oxycarbonyl group, It represents a group containing an ether group, a hydroxyl group, an amide group, or an aryl group. Alkyl group, cycloalkyl group, carbonyl group-containing group, carbonyloxy group-containing group, oxycarbonyl group-containing group, ether group-containing group, amide group, aryl group part or all of hydrogen atoms are fluorine atoms May be substituted. Any _{two of} R ₂ , R ₃ and R ₄ may be linked to form a ring.

  n is 0 or 1.

(5) Furthermore,
(A) a resin that is decomposed by the action of an acid and has increased solubility in an alkaline developer;
(B) The actinic ray-sensitive property according to any one of (1) to (4), comprising a compound that generates an acid upon irradiation with actinic rays or radiation, and (C) a solvent. Radiation sensitive resin composition.

  (6) The actinic ray-sensitive or radiation-sensitive resin composition according to (5), wherein the resin (A) contains a repeating unit containing a lactone structure.

(7) The actinic ray-sensitive or radiation-sensitive resin according to (6), wherein the repeating unit containing a lactone structure of the resin (A) is a repeating unit represented by the following general formula (II): Composition.

In the formula, A represents an ester bond (—COO—) or an amide bond (—CONH—).
R ₀ independently represents an alkylene group, a cycloalkylene group, or a combination thereof when there are a plurality of R ₀ .
Z is independently an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond when there are a plurality of Z.
R ₈ represents a monovalent organic group having a lactone structure.
n is a repeating number and represents an integer of 1 to 5.
R ₇ represents a hydrogen atom, a halogen atom or an alkyl group which may have a substituent.

  (8) The sensation according to any one of (5) to (7), wherein the resin (A) contains a repeating unit containing a monocyclic or polycyclic acid-decomposable group. An actinic ray-sensitive or radiation-sensitive resin composition.

(9) The actinic ray-sensitive or radiation-sensitive composition according to (8), wherein the repeating unit containing an acid-decomposable group in the resin (A) is a repeating unit represented by the following general formula (III): Resin composition.

In general formula (III),
R ₃ represents a hydrogen atom, a methyl group which may have a substituent, or a group represented by —CH ₂ —R ₉ . R ₉ represents a hydroxyl group or a monovalent organic group.
R ₄ and R ₅ each independently represents an alkyl group (straight or branched) or a cycloalkyl group (monocyclic or polycyclic).
L represents a divalent linking group.
n ₁ is 0 or 1.
P represents a polar group.
p shows the integer of 1-15.

  (10) From (1), wherein the content of the resin (HR) is 0.01 to 10% by mass with respect to the total solid content in the actinic ray-sensitive or radiation-sensitive resin composition. The actinic ray-sensitive or radiation-sensitive resin composition according to any one of (9).

  (11) A step of forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (10), and exposing and developing the film. A pattern forming method.

  (12) The pattern forming method according to (11), wherein exposure is performed through an immersion liquid.

  According to the present invention, it is possible to provide a resist pattern having few LWR defects, bubble defects and development residue defects and having an excellent LWR.

Hereinafter, the present invention will be described in detail.
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).

[1] Resin (HR)
The resin (HR) contained in the actinic ray-sensitive or radiation-sensitive resin composition of the present invention has a repeating unit (a) having a polycyclic structure in the main chain.
The polycyclic structure of the repeating unit (a) includes a site that is decomposed by the action of an acid and increases the solubility in an alkaline developer. In one embodiment, this site is a general formula (pI) to (pV) described later. It may be any structure selected from
The repeating unit (a) is preferably a repeating unit represented by the following general formula (I).

In the general formula (I), R1 represents a group that decomposes by the action of an acid.
R ₁ preferably has a structure selected from the following general formulas (pI) to (pV).

In the general formulas (pI) to (pV),
R ₁₁ represents an alkyl group or a cycloalkyl group.
Z represents an atomic group necessary for forming a cycloalkyl group together with a carbon atom.
R _{12 to} R ₁₄ each independently represents an alkyl group or a cycloalkyl group.
R ₁₅ and R ₁₆ each independently represents an alkyl group or a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group. However, either R ₁₉ or R ₂₁ represents an alkyl group or a cycloalkyl group.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In the general formulas (pI) to (pV), the alkyl group in R _{11 to} R ₂₅ is preferably a linear or branched alkyl group having 1 to 8 carbon atoms, such as a methyl group, an ethyl group, or a propyl group. , N-butyl group, sec-butyl group, t-butyl group and the like.

The cycloalkyl group in R _{11 to} R ₂₅ or the cycloalkyl group formed by Z and the 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 4 to 30, and particularly preferably 5 to 25. The cycloalkyl group may have an unsaturated double bond in the ring. The cycloalkyl group may have a substituent.

Further, the cycloalkyl group in R _{11 to} R ₂₅ or the cycloalkyl group formed by Z and the carbon atom is more preferably monocyclic, and the cycloalkyl group preferably has 4 to 10 carbon atoms, most preferably. Has 5 to 7 carbon atoms.

  Preferred cycloalkyl groups include adamantyl group, noradamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, A cyclodecanyl group and a cyclododecanyl group can be mentioned. More preferable examples include an adamantyl group, norbornyl group, cyclohexyl group, cyclopentyl group, tetracyclododecanyl group, and tricyclodecanyl group.

  These alkyl groups and cycloalkyl groups may further have a substituent. As further substituents for alkyl groups and cycloalkyl groups, alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, alkoxycarbonyl groups (2 to 2 carbon atoms). 6). The above alkyl group, alkoxy group, alkoxycarbonyl group and the like may further have a substituent. Examples of the substituent that the alkyl group, alkoxy group, alkoxycarbonyl group and the like may further have include a hydroxyl group, a halogen atom, and an alkoxy group.

R ₂ , R ₃ and R ₄ each independently represents a hydrogen atom, a fluorine atom, an alkyl group, a cycloalkyl group, a group containing a carbonyl group, a group containing a carbonyloxy group, a group containing an oxycarbonyl group, or an ether group. A group containing, a hydroxyl group, an amide group or an aryl group. In addition, alkyl groups, cycloalkyl groups, groups containing carbonyl groups, groups containing carbonyloxy groups, groups containing oxycarbonyl groups, groups containing ether groups, amide groups, aryl groups, or some or all of the hydrogen atoms are fluorine atoms. An atom may be substituted, and any two of R ₂ , R ₃ and R ₄ may be linked to form a ring.

The alkyl group in R ₂ , R ₃ , and R ₄ is preferably a linear or branched alkyl group having 1 to 8 carbon atoms. For example, 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 alkyl group may have a substituent.

The cycloalkyl group in R ₂ , R ₃ and R ₄ 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 4 to 30, and particularly preferably 5 to 25. The cycloalkyl group may have an unsaturated double bond in the ring. The cycloalkyl group may have a substituent.

The group containing a carbonyl group in R ₂ , R ₃ and R ₄ is preferably a carbonyl group substituted with a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. Group, t-butylcarbonyl group, cyclopentylcarbonyl group, cyclohexylcarbonyl group and the like.

The group containing a carbonyloxy group in R ₂ , R ₃ , and R ₄ is preferably a carbonyloxy group substituted with a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, such as a methylcarbonyloxy group. , Ethylcarbonyloxy group, cyclopentylcarbonyloxy group, cyclohexylcarbonyloxy group and the like.

The group containing an oxycarbonyl group in R ₂ , R ₃ , and R ₄ is preferably a carbonyloxy group substituted with a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, such as a carbonyloxymethyl group. Carbonyloxyethyl group, carbonyloxycyclopentyl group, carbonyloxycyclohexyl group and the like.

The group containing an ether group in R ₂ , R ₃ , and R ₄ is preferably an ether group substituted with a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, such as a methoxy group, an ethoxy group, A t-butoxy group, a cyclopentyloxy group, a cyclohexyloxy group and the like can be mentioned.

Examples of the amide group in R ₂ , R ₃ and R ₄ include a dimethylamide group, a diethylamide group, a methylethylamide group, a dicyclohexylamide group, and a methylcyclohexylamide group.
Examples of the aryl group in R ₂ , R ₃ , and R ₄ include a phenyl group and a naphthyl group. The aryl group may have a substituent.
n is 0 or 1, and n = 0 is preferable.

Hereinafter, although the specific example of the repeating unit shown by general formula (I) is given, this invention is not limited to this.

  Resin (HR) contains a fluorine atom. The repeating unit (a) may contain a fluorine atom, or may further have a repeating unit containing a fluorine atom in addition to the repeating unit (a) as described in detail below.

  The partial structure having a fluorine atom is preferably a resin having an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or an aryl group having a fluorine atom.

  The alkyl group having a fluorine atom (preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms) is a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, It may have a substituent.

  The cycloalkyl group having a fluorine atom is a monocyclic or polycyclic cycloalkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and may further have another substituent.

  Examples of the aryl group having a fluorine atom include those in which at least one hydrogen atom of an aryl group such as a phenyl group or a naphthyl group is substituted with a fluorine atom, and may further have another substituent.

Preferred examples of the alkyl group having a fluorine atom, the cycloalkyl group having a fluorine atom, or the aryl group having a fluorine atom include groups represented by the following general formulas (F2) to (F4). The present invention is not limited to this.

In general formulas (F2) to (F4),
R _{57 to} R ₆₈ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. Provided that at least one of R _{57 to} R ₆₁ , at least one of R _{62 to} R ₆₄ , and at least one of R _{65 to} R ₆₈ are a fluorine atom or an alkyl having at least one hydrogen atom substituted with a fluorine atom. Represents a group (preferably having 1 to 4 carbon atoms). R _{57 to} R ₆₁ and R _{65 to} R ₆₇ are preferably all fluorine atoms. R ₆₂ , R ₆₃ and R ₆₈ are preferably an alkyl group (preferably having 1 to 4 carbon atoms) in which at least one hydrogen atom is substituted with a fluorine atom, and preferably a perfluoroalkyl group having 1 to 4 carbon atoms. Further preferred. R ₆₂ and R ₆₃ may be connected to each other to form a ring.

  Specific examples of the group represented by the general formula (F2) include a p-fluorophenyl group, a pentafluorophenyl group, and a 3,5-di (trifluoromethyl) phenyl group.

  Specific examples of the group represented by the general formula (F3) include trifluoromethyl group, pentafluoropropyl group, pentafluoroethyl group, heptafluorobutyl group, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2 -Methyl) isopropyl group, nonafluorobutyl group, octafluoroisobutyl group, nonafluorohexyl group, nonafluoro-t-butyl group, perfluoroisopentyl group, perfluorooctyl group, perfluoro (trimethyl) hexyl group, 2,2 1,3,3-tetrafluorocyclobutyl group, perfluorocyclohexyl group and the like. Hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2-methyl) isopropyl group, octafluoroisobutyl group, nonafluoro-t-butyl group and perfluoroisopentyl group are preferable, and hexafluoroisopropyl group and heptafluoroisopropyl group are preferable. Further preferred.

Specific examples of the group represented by the general formula (F4) include, for example, —C (CF ₃ ) ₂ OH, —C (C ₂ F ₅ ) ₂ OH, —C (CF ₃ ) (CH ₃ ) OH, -CH (CF ₃₎ OH and the like, -C (CF _{3) 2} OH is preferred.

Hereinafter, although the specific example of the repeating unit which has a fluorine atom is shown, this invention is not limited to this.
In specific examples, X ₁ and X ₂ represent —F or —CF ₃ .

10-90 mol% is preferable with respect to all the repeating units in resin (HR), and, as for the content rate of the repeating unit (a) which resin (HR) has, 20-80 mol% is more preferable.
Further, the content of the repeating unit containing a fluorine atom other than the repeating unit (a) in the resin (HR) is preferably 10 to 90 mol% with respect to all repeating units in the resin (HR), and 20 to 80 mol. % Is more preferable.

  Furthermore, the content of fluorine atoms in the hydrophobic resin (HR) is preferably 5 to 80% by mass and more preferably 10 to 80% by mass with respect to the molecular weight of the hydrophobic resin (HR) described later. preferable.

The hydrophobic resin (HR) may contain a silicon atom. The partial structure having a silicon atom is preferably a resin having an alkylsilyl structure (preferably a trialkylsilyl group) or a cyclic siloxane structure.
Specific examples of the alkylsilyl structure or the cyclic siloxane structure include groups represented by the following general formulas (CS-1) to (CS-3).

In general formulas (CS-1) to (CS-3),
R _{12 to} R ₂₆ each independently represents a linear or branched alkyl group (preferably having 1 to 20 carbon atoms) or a cycloalkyl group (preferably having 3 to 20 carbon atoms).

L < ₃ > -L < ₅ > represents a single bond or a bivalent coupling group. As the divalent linking group, an alkylene group, a phenylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a urethane group, or a urea group is used alone or in combination of two or more groups. A combination is mentioned.

  n represents an integer of 1 to 5.

Hereinafter, although the specific example of the repeating unit which has group represented by general formula (CS-1)-(CS-3) is given, this invention is not limited to this. In specific examples, X ₁ represents a hydrogen atom, —CH ₃ , —F or —CF ₃ .

  Furthermore, the hydrophobic resin (HR) may have at least one group selected from the following groups (x) to (z).

(X) an alkali-soluble group,
(Y) a group that decomposes by the action of an alkali developer and increases the solubility in the alkali developer;
(Z) A group that decomposes by the action of an acid.

  (X) Alkali-soluble groups include phenolic hydroxyl groups, carboxylic acid groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, (alkylsulfonyl) ( Alkylcarbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) ) And a methylene group.

  Preferred alkali-soluble groups include fluorinated alcohol groups (preferably hexafluoroisopropanol), sulfonimide groups, and bis (carbonyl) methylene groups.

  Examples of the repeating unit having an alkali-soluble group (x) include a repeating unit in which an alkali-soluble group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or a main group of the resin via a linking group. Examples include repeating units in which an alkali-soluble group is bonded to the chain. Furthermore, a polymerization initiator or a chain transfer agent having an alkali-soluble group can be used at the time of polymerization to be introduced at the end of the polymer chain. Is also preferable.

  The content of the repeating unit having an alkali-soluble group (x) is preferably from 1 to 50 mol%, more preferably from 3 to 35 mol%, still more preferably from 5 to 20 mol%, based on all repeating units in the polymer.

Specific examples of the repeating unit having an alkali-soluble group (x) are shown below, but the present invention is not limited thereto. In specific examples, Rx represents H, CH ₃ , CH ₂ OH, or CF ₃ .

  (Y) Examples of the group that decomposes by the action of an alkali developer and increases the solubility in the alkali developer include a group having a lactone structure, an acid anhydride group, an acid imide group, and the like, and preferably a lactone A group having a structure.

  As the repeating unit having a group (y) that is decomposed by the action of an alkali developer and increases the solubility in the alkali developer, an alkali is added to the main chain of the resin, such as a repeating unit of an acrylate ester or a methacrylate ester. A polymerization initiator having a repeating unit to which a group (y) that decomposes by the action of the developer and increases the solubility in an alkali developer is bonded, or a group (y) that increases the solubility in an alkali developer And a chain transfer agent used at the time of polymerization are preferably introduced at the end of the polymer chain.

  The content of the repeating unit having a group (y) whose solubility in an alkali developer is increased is preferably 1 to 40 mol%, more preferably 3 to 30 mol%, still more preferably based on all repeating units in the polymer. 5 to 15 mol%.

  Specific examples of the repeating unit having a group (y) that increases the solubility in an alkali developer include the same repeating units as those having a lactone structure exemplified for the resin of the component (B).

  In the hydrophobic resin (HR), examples of the repeating unit having a group (z) that is decomposed by the action of an acid are the same as the repeating unit having an acid-decomposable group exemplified in the resin of the component (B). . In the hydrophobic resin (HR), the content of the repeating unit having a group (z) that is decomposed by the action of an acid is preferably 1 to 80 mol%, more preferably 10 to 10%, based on all repeating units in the polymer. 80 mol%, more preferably 20 to 60 mol%.

The hydrophobic resin (HR) may further have a repeating unit represented by the following general formula (VI).

In general formula (VI):
R _c31 represents a hydrogen atom, an alkyl group, or an alkyl group optionally substituted with fluorine, a cyano group, or a —CH ₂ —O—Rac ₂ group. Wherein, Rac ₂ represents a hydrogen atom, an alkyl group or an acyl group. R _c31 is preferably a hydrogen atom, a methyl group, a hydroxymethyl group or a trifluoromethyl group, particularly preferably a hydrogen atom or a methyl group.

R _c32 represents a group having an alkyl group, a cycloalkyl group, an alkenyl group, or a cycloalkenyl group. These groups may be substituted with a fluorine atom or a silicon atom.
L _c3 represents a single bond or a divalent linking group.

In general formula (VI), the alkyl group represented by R _c32 is preferably a linear or branched alkyl group having 3 to 20 carbon atoms.
The cycloalkyl group is preferably a cycloalkyl group having 3 to 20 carbon atoms.
The alkenyl group is preferably an alkenyl group having 3 to 20 carbon atoms.
The cycloalkenyl group is preferably a cycloalkenyl group having 3 to 20 carbon atoms.
R _c32 is preferably an unsubstituted alkyl group or an alkyl group substituted with a fluorine atom.
The divalent linking group of L _c3 is preferably an ester group, an alkylene group (preferably having 1 to 5 carbon atoms), an oxy group, or a phenylene group.

  The repeating unit represented by the general formula (VI) preferably has no acid-decomposable group.

  When the hydrophobic resin (HR) has a silicon atom, the content of the silicon atom is preferably 2 to 50% by mass and preferably 2 to 30% by mass with respect to the molecular weight of the hydrophobic resin (HR). Is more preferable. Moreover, it is preferable that it is 10-100 mass% in hydrophobic resin (HR), and, as for the repeating unit containing a silicon atom, it is more preferable that it is 20-100 mass%.

  The weight average molecular weight of the hydrophobic resin (HR) in terms of standard polystyrene is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, and even more preferably 2,000 to 15,000. is there.

  The content of the hydrophobic resin (HR) in the composition is preferably 0.01 to 10% by mass, more preferably 0.05 to 8% by mass, based on the total solid content in the composition of the present invention. More preferably, the content is 1 to 5% by mass.

  The hydrophobic resin (HR), like the resin of the component (A), naturally has few impurities such as metals, and the residual monomer and oligomer components are preferably 0 to 10% by mass, more preferably. Is more preferably 0 to 5% by mass and 0 to 1% by mass. Thereby, a resist having no change over time such as foreign matter in liquid or sensitivity can be obtained. The molecular weight distribution (Mw / Mn, also referred to as dispersity) is preferably in the range of 1 to 5, more preferably 1 to 3, and still more preferably from the viewpoints of resolution, resist shape, resist pattern sidewall, roughness, and the like. It is the range of 1-2.

  As the hydrophobic resin (HR), various commercially available products can be used, or they can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and the polymerization is performed by heating, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as the solvent used in the positive resist composition of the present invention. Thereby, generation | occurrence | production of the particle at the time of a preservation | save can be suppressed.

  The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred examples of the initiator include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. The concentration of the reaction is 5 to 50% by mass, preferably 30 to 50% by mass. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 60-100 ° C.

  After completion of the reaction, the mixture is allowed to cool to room temperature and purified. Purification can be accomplished by a liquid-liquid extraction method that removes residual monomers and oligomer components by combining water and an appropriate solvent, and a purification method in a solution state such as ultrafiltration that extracts and removes only those having a specific molecular weight or less. , Reprecipitation method that removes residual monomer by coagulating resin in poor solvent by dripping resin solution into poor solvent and purification in solid state such as washing filtered resin slurry with poor solvent A normal method such as a method can be applied. For example, the resin is precipitated as a solid by contacting a solvent (poor solvent) in which the resin is hardly soluble or insoluble in a volume amount of 10 times or less, preferably 10 to 5 times that of the reaction solution.

  The solvent (precipitation or reprecipitation solvent) used in the precipitation or reprecipitation operation from the polymer solution may be a poor solvent for the polymer, and may be a hydrocarbon, halogenated hydrocarbon, nitro, depending on the type of polymer. A compound, ether, ketone, ester, carbonate, alcohol, carboxylic acid, water, a mixed solvent containing these solvents, and the like can be appropriately selected for use. Among these, as a precipitation or reprecipitation solvent, a solvent containing at least an alcohol (particularly methanol or the like) or water is preferable.

  The amount of the precipitation or reprecipitation solvent used can be appropriately selected in consideration of efficiency, yield, and the like, but generally 100 to 10000 parts by mass, preferably 200 to 2000 parts by mass with respect to 100 parts by mass of the polymer solution, More preferably, it is 300-1000 mass parts.

  The temperature for precipitation or reprecipitation can be appropriately selected in consideration of efficiency and operability, but is usually about 0 to 50 ° C., preferably around room temperature (for example, about 20 to 35 ° C.). The precipitation or reprecipitation operation can be performed by a known method such as a batch method or a continuous method using a conventional mixing vessel such as a stirring tank.

  The precipitated or re-precipitated polymer is usually subjected to conventional solid-liquid separation such as filtration and centrifugation, and dried before use. Filtration is performed using a solvent-resistant filter medium, preferably under pressure. Drying is performed at a temperature of about 30 to 100 ° C., preferably about 30 to 50 ° C. under normal pressure or reduced pressure (preferably under reduced pressure).

  The resin may be once deposited and separated, and then dissolved again in a solvent, and the resin may be brought into contact with a hardly soluble or insoluble solvent. That is, after completion of the radical polymerization reaction, a solvent in which the polymer is hardly soluble or insoluble is brought into contact, the resin is precipitated (step a), the resin is separated from the solution (step b), and dissolved again in the solvent. (Step c), and then contact the resin solution A with a solvent in which the resin is hardly soluble or insoluble in a volume amount less than 10 times that of the resin solution A (preferably 5 times or less volume). This may be a method including precipitating a resin solid (step d) and separating the precipitated resin (step e).

  The film comprising the actinic ray-sensitive or radiation-sensitive resin composition of the present invention is filled with a liquid (immersion medium) having a higher refractive index than air between the film and the lens when irradiated with actinic rays or radiation. Exposure (immersion exposure) may be performed. Thereby, resolution can be improved. As the immersion medium to be used, any liquid can be used as long as it has a higher refractive index than air, but pure water is preferred.

  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 film. Is 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-mentioned viewpoints.

  Further, a medium having a refractive index of 1.5 or more can be used in that the refractive index can be further improved. This medium may be an aqueous solution or an organic solvent.

  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 film 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 material or impurities whose refractive index is significantly different from that of water are mixed with 193 nm light, the optical image projected on the resist film is distorted. . Further, pure water filtered through an ion exchange filter or the like may be used.

  The electrical resistance of water is desirably 18.3 MQcm or more, the TOC (organic substance concentration) is desirably 20 ppb or less, and deaeration treatment is desirably performed.

Moreover, it is possible to improve lithography performance by increasing the refractive index of the immersion liquid. From such a viewpoint, an additive for increasing the refractive index may be added to water, or heavy water (D ₂ O) may be used instead of water.

  When exposing the film | membrane which consists of a composition of this invention through an immersion medium, hydrophobic resin (HR) can be further added as needed. As a result, the hydrophobic resin (HR) is unevenly distributed on the surface layer of the film, and when the immersion medium is water, the receding contact angle of the resist film surface with respect to the water when used as a film is improved, and the immersion water followability is improved. Can do. By adding the hydrophobic resin (HR), the receding contact angle of the surface is improved. The receding contact angle of the film is preferably 60 ° to 90 °, more preferably 70 ° or more. Hydrophobic resin (HR) is unevenly distributed at the interface as described above, but unlike a surfactant, it does not necessarily have a hydrophilic group in the molecule, and polar / nonpolar substances should be mixed uniformly. It does not have to contribute to

  The receding contact angle is the contact angle measured when the contact line at the droplet-substrate interface recedes, and is useful for simulating the ease of droplet movement under dynamic conditions. It is generally known. In simple terms, it can be defined as the contact angle when the droplet interface recedes when the droplet discharged from the needle tip is deposited on the substrate and then sucked into the needle again. It can be measured by using a contact angle measuring method generally called an expansion / contraction method.

  In the immersion exposure process, the immersion head needs to move on the wafer following the movement of the exposure head to scan the wafer at high speed to form the exposure pattern. In this case, the contact angle of the immersion liquid with respect to the resist film is important, and the resist is required to follow the high-speed scanning of the exposure head without remaining droplets.

  An immersion liquid poorly soluble film (hereinafter also referred to as “topcoat”) may be provided between the film of the composition of the present invention and the immersion liquid so that the film does not directly contact the immersion liquid. Good. 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 top coat is preferably a polymer that does not contain abundant aromatics. Specifically, the polymer contains a hydrocarbon polymer, an acrylate polymer, polymethacrylic acid, polyacrylic acid, polyvinyl ether, and silicon. Examples thereof include a polymer and a fluorine-containing polymer. The aforementioned hydrophobic resin (HR) is also suitable as a top coat. From the viewpoint of contaminating the optical lens when impurities are eluted from the top coat into the immersion liquid, it is preferable that the residual monomer component of the polymer contained in the top coat is small.

  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 low penetration into the film is preferable. In terms of being able to perform the peeling process simultaneously with the film development process, it is preferable that the peeling process can be performed with an alkaline developer. The top coat is preferably acidic from the viewpoint of peeling with an alkali developer, but may be neutral or alkaline from the viewpoint of non-intermixability with the film.

  The resolution is improved when there is no difference in refractive index between the top coat and the immersion liquid. In the case of using water as the immersion liquid in an ArF excimer laser (wavelength: 193 nm), the top coat for ArF immersion exposure is preferably close to the refractive index of the immersion liquid. From the viewpoint of making the refractive index close to the immersion liquid, it is preferable to have fluorine atoms in the topcoat. A thin film is more preferable from the viewpoint of transparency and refractive index.

  The top coat is preferably not mixed with the membrane and further not mixed with the immersion liquid. From this point of view, when the immersion liquid is water, the solvent used for the top coat is preferably a water-insoluble medium that is hardly soluble in the solvent used for the composition of the present invention. Furthermore, when the immersion liquid is an organic solvent, the topcoat may be water-soluble or water-insoluble.

[2] Resin (A) which is decomposed by the action of an acid to increase the solubility in an alkaline developer
The actinic ray-sensitive or radiation-sensitive resin composition of the present invention may contain a resin (A) that is decomposed by the action of an acid and increases the solubility in an alkali developer.
A resin (acid-decomposable resin) whose solubility in an alkaline developer is increased by the action of an acid is a group (hereinafter referred to as an “acid-soluble group”) that decomposes into the main chain and / or side chain of the resin by the action of an acid to produce an alkali-soluble group. Also referred to as “degradable group”.
The resin (A) is preferably insoluble or hardly soluble in an alkali developer.

The acid-decomposable group preferably has a structure protected with a group capable of decomposing and leaving an alkali-soluble group by the action of an acid.
The alkali-soluble group is not particularly limited as long as it is a group that dissociates and becomes an ion in an alkali developer. Preferred alkali-soluble groups include a carboxyl group, a fluorinated alcohol group (preferably hexafluoroisopropanol), and a sulfonic acid. Groups.

A preferable group as the acid-decomposable group is a group in which the hydrogen atom of these alkali-soluble groups is substituted with a group capable of leaving with an acid.
Examples of the group leaving with an acid include -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), -C (R ₀₁ ) (R ₀₂ ). ) (OR ₃₉ ) and the like.
In the formula, R _{36 to} R ₃₉ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be bonded to each other to form a ring.
R _{01 and} R ₀₂ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.
The acid-decomposable group is preferably a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like. More preferably, it is a tertiary alkyl ester group.

The repeating unit having an acid-decomposable group that can be contained in the resin (A) is preferably a repeating unit represented by the following general formula (AI).

In general formula (AI),
Xa ₁ represents a hydrogen atom, a methyl group which may have a substituent, or a group represented by —CH ₂ —R ₉ . R ₉ represents a hydroxyl group or a monovalent organic group. Examples of the monovalent organic group include an alkyl group having 5 or less carbon atoms and an acyl group, preferably an alkyl group having 3 or less carbon atoms, and more preferably a methyl group. Xa ₁ preferably represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.

T represents a single bond or a divalent linking group.
Rx _{1 to} Rx ₃ each independently represents an alkyl group (straight or branched) or a cycloalkyl group (monocyclic or polycyclic).
At least two of Rx _{1 to} Rx ₃ may combine to form a cycloalkyl group (monocyclic or polycyclic).

Examples of the divalent linking group for T include an alkylene group, —COO—Rt— group, —O—Rt— group, and the like. In the formula, Rt represents an alkylene group or a cycloalkylene group.
T is preferably a single bond or a —COO—Rt— group. Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a —CH ₂ — group or a — (CH ₂ ) ₃ — group.
The alkyl group of Rx _{1 to} Rx ₃ is preferably an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group.

Examples of the cycloalkyl group represented by Rx _{1 to} Rx ₃ include monocyclic cycloalkyl groups such as cyclopentyl group and cyclohexyl group, polycyclic cycloalkyl groups such as norbornyl group, tetracyclodecanyl group, tetracyclododecanyl group, and adamantyl group. Groups are preferred.
Examples of the cycloalkyl group formed by combining at least two of Rx _{1 to} Rx ₃ include a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, A polycyclic cycloalkyl group such as an adamantyl group is preferred.
It is preferable that Rx ₁ is a methyl group or an ethyl group, and Rx ₂ and Rx ₃ are bonded to form the above-described cycloalkyl group.

  Each of the above groups may have a substituent. Examples of the substituent include an alkyl group (1 to 4 carbon atoms), a halogen atom, a hydroxyl group, an alkoxy group (1 to 4 carbon atoms), a carboxyl group, An alkoxycarbonyl group (C2-C6) etc. are mentioned, C8 or less is preferable.

  The content of the repeating unit having an acid-decomposable group as a total is preferably 20 to 70 mol%, more preferably 30 to 50 mol%, based on all repeating units in the resin.

  Although the specific example of the repeating unit which has a preferable acid-decomposable group is shown below, this invention is not limited to this.

In specific examples, Rx and Xa ₁ represent a hydrogen atom, CH ₃ , CF ₃ , or CH ₂ OH. Rxa and Rxb each represents an alkyl group having 1 to 4 carbon atoms. Z represents a substituent containing a polar group, and when there are a plurality of them, each is independent. p represents 0 or a positive integer.

The resin (A) is a resin having at least one of the repeating unit represented by the general formula (1) and the repeating unit represented by the general formula (2) as the repeating unit represented by the general formula (AI). It is more preferable.

In formulas (1) and (2),
R ₁ and R ₃ each independently represents a hydrogen atom, an optionally substituted methyl group or a group represented by —CH ₂ —R ₉ . R ₉ represents a hydroxyl group or a monovalent organic group.
R ₂ , R ₄ , R ₅ and R ₆ each independently represents an alkyl group or a cycloalkyl group.
R represents an atomic group necessary for forming an alicyclic structure together with a carbon atom.

R ₁ preferably represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.

The alkyl group in R ₂ may be linear or branched, and may have a substituent.
The cycloalkyl group in R ₂ may be monocyclic or polycyclic and may have a substituent.
R ₂ is preferably an alkyl group, more preferably an alkyl group having 1 to 10 carbon atoms, still more preferably 1 to 5 carbon atoms, and examples thereof include a methyl group and an ethyl group.

  R represents an atomic group necessary for forming an alicyclic structure together with a carbon atom. The alicyclic structure formed by R is preferably a monocyclic alicyclic structure, and the carbon number thereof is preferably 3 to 7, more preferably 5 or 6.

R ₃ is preferably a hydrogen atom or a methyl group, more preferably a methyl group.
The alkyl group in R ₄ , R ₅ and R ₆ may be linear or branched and may have a substituent. As the alkyl group, those having 1 to 4 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group and t-butyl group are preferable.
The cycloalkyl group in R ₄ , R ₅ and R ₆ may be monocyclic or polycyclic and may have a substituent. The cycloalkyl group is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group or an adamantyl group.
The repeating unit represented by the general formula (2) is preferably a repeating unit represented by the following general formula (2-1).

In formula (2-1),
R < ₃ > -R < ₅ > is synonymous with the thing in General formula (2).
R ₁₀ represents a substituent containing a polar group. When a plurality of R ₁₀ are present, they may be the same as or different from each other. Examples of the substituent containing a polar group include a linear or branched alkyl group or cycloalkyl group having a hydroxyl group, a cyano group, an amino group, an alkylamide group or a sulfonamide group, and preferably a hydroxyl group. It is an alkyl group. More preferably, it is a branched alkyl group having a hydroxyl group.
p represents an integer of 0 to 15. p is preferably 0 to 2, more preferably 0 or 1.
The repeating unit represented by the general formula (2-1) is preferably a repeating unit represented by the following general formula (III).

In general formula (III), R < ₃ > -R < ₅ > is synonymous with the thing in general formula (2-1).
R ₃ represents a hydrogen atom, a methyl group which may have a substituent, or a group represented by —CH ₂ —R ₉ . R ₉ represents a hydroxyl group or a monovalent organic group.

R ₄ and R ₅ each independently represents an alkyl group (straight or branched) or a cycloalkyl group (monocyclic or polycyclic).
L represents a divalent linking group. n ₁ is 0 or 1. P represents a polar group. n ₂ represents an integer of 1 to 13, preferably from 0 to 2, more preferably 0 or 1.
Examples of the divalent linking group represented by L include a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, a carbonyl group, and an oxycarbonyl group. A branched alkyl group is preferred, and an isopropyl group is particularly preferred.
Examples of the polar group represented by P include a hydroxyl group, a cyano group, an amino group, an alkylamide group, or a sulfonamide group.

Preferred combinations when the resin (A) uses an acid-decomposable repeating unit are listed below.

The resin (A) preferably contains a repeating unit having a lactone group.
Any lactone group can be used as long as it has a lactone structure, but it is preferably a 5- to 7-membered ring lactone structure, and forms a bicyclo structure or a spiro structure in the 5- to 7-membered ring lactone structure. The other ring structure is preferably condensed. It is more preferable to have a repeating unit having a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-17). The lactone structure may be directly bonded to the main chain. Preferred lactone structures are (LC1-1), (LC1-4), (LC1-5), (LC1-6), (LC1-13), (LC1-14), and (LC1-17). By using this lactone structure, LWR and development defects are improved.

The lactone structure moiety may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. More preferably, they are a C1-C4 alkyl group, a cyano group, and an acid-decomposable group. n ₂ represents an integer of 0-4. When n ₂ is 2 or more, the plurality of substituents (Rb ₂ ) may be the same or different. A plurality of substituents (Rb ₂ ) may be bonded to form a ring.
The repeating unit having a lactone structure is preferably a repeating unit represented by the following general formula (AII).

In general formula (AII),
Rb ₀ represents a hydrogen atom, a halogen atom or an optionally substituted alkyl group having 1 to 4 carbon atoms. Preferred substituents that the alkyl group represented by Rb ₀ may have include a hydroxyl group and a halogen atom. Examples of the halogen atom for Rb ₀ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Rb ₀ is preferably a hydrogen atom, a methyl group, a hydroxymethyl group, or a trifluoromethyl group, and particularly preferably a hydrogen atom or a methyl group.

Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent linking group obtained by combining these. Preferably a single bond, -Ab ₁ -CO ₂ - is a divalent linking group represented by.

Ab ₁ is a linear, branched alkylene group, monocyclic or polycyclic cycloalkylene group, preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group or a norbornylene group.

V represents a group having a lactone structure. Specifically, for example, it represents a group having a structure represented by any of the general formulas (LC1-1) to (LC1-17).
Among the units represented by the general formula (AII), the following repeating units are particularly preferable as the repeating unit having a lactone group when Ab is a single bond. In specific examples, Rx represents H, CH ₃ , CH ₂ OH, or CF ₃ . By selecting an optimal lactone group, the pattern profile and the density dependency are improved.

The resin (A) preferably contains a repeating unit having a lactone structure represented by the following general formula (II).

In the formula, A represents an ester bond or an amide bond.
R ₀ independently represents an alkylene group, a cycloalkylene group, or a combination thereof when there are a plurality of R ₀ .
Z is independently an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond when there are a plurality of Z.
R ₈ represents a monovalent organic group having a lactone structure.
n is a repeating number and represents an integer of 1 to 5.
R ₇ represents a hydrogen atom, a halogen atom or an alkyl group which may have a substituent.

The alkylene group and cycloalkylene group of R0 may have a substituent.
Z is preferably an ether bond or an ester bond, and particularly preferably an ester bond.

The alkyl group for R ₇ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. The alkyl group in R ₇ may be substituted. Examples of the substituent include halogen atoms such as fluorine atom, chlorine atom and bromine atom, mercapto group, hydroxy group, methoxy group, ethoxy group, isopropoxy group, t -Acetoxy groups such as alkoxy groups such as butoxy group and benzyloxy group, acetyl groups and propionyl groups. R ₇ is preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

Preferable chain alkylene group in R ₀ is preferably a chain alkylene having 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and examples thereof include a methylene group, an ethylene group, and a propylene group. Preferred cycloalkylene is cycloalkylene having 6 to 20 carbon atoms, and examples thereof include cyclohexylene, cyclopentylene, norbornylene, adamantylene and the like. In order to exhibit the effect of the present invention, a chain alkylene group is more preferable, and a methylene group is particularly preferable.

The substituent having a lactone structure represented by R ₈ is not limited as long as it has a lactone structure, and specific examples include lactones represented by general formulas (LC1-1) to (LC1-17). The structure is mentioned, Of these, the structure represented by (LC1-4) is particularly preferable. Further, n ₂ in (LC1-1) to (LC1-17) is more preferably 2 or less.
R ₈ is preferably a monovalent organic group having an unsubstituted lactone structure or a monovalent organic group having a lactone structure having a methyl group, a cyano group or an alkoxycarbonyl group as a substituent. A monovalent organic group having a lactone structure (cyanolactone) as is more preferable.

Specific examples of the repeating unit having a group having a lactone structure represented by the general formula (II) are shown below, but the present invention is not limited thereto.
In the following specific examples, R represents a hydrogen atom, an alkyl group which may have a substituent, or a halogen atom, and preferably a hydrogen atom, a methyl group, a hydroxymethyl group which is an alkyl group having a substituent, acetoxy Represents a methyl group.

The repeating unit having a lactone structure is more preferably a repeating unit represented by the following general formula (II-1).

In general formula (II-1),
R ₇ , A, R ₀ , Z, and n are as defined in the general formula (II).
R ₉ independently represents an alkyl group, a cycloalkyl group, an alkoxycarbonyl group, a cyano group, a hydroxyl group or an alkoxy group, when there are a plurality of R _{9 s} , May be formed.

X represents an alkylene group, an oxygen atom or a sulfur atom.
m is the number of substituents and represents an integer of 0 to 5. m is preferably 0 or 1.

The alkyl group for R ₉ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and most preferably a methyl group. Examples of the cycloalkyl group include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups. Examples of the ester group include a methoxycarbonyl group, an ethoxycarbonyl group, an n-butoxycarbonyl group, and a t-butoxycarbonyl group. Examples of the substituent include an alkoxy group such as a hydroxy group, a methoxy group, and an ethoxy group, and a halogen atom such as a cyano group and a fluorine atom.

R ₉ is more preferably a methyl group, a cyano group, or an alkoxycarbonyl group, and even more preferably a cyano group.

  Examples of the alkylene group for X include a methylene group and an ethylene group. X is preferably an oxygen atom or a methylene group, more preferably a methylene group.

When m = 1, R ₉ is preferably substituted at the α-position or β-position of the carbonyl group of the lactone, and particularly preferably substituted at the α-position.

Specific examples of the repeating unit having a group having a lactone structure represented by formula (II-1) are shown below, but the present invention is not limited thereto. In the formula, R represents a hydrogen atom, an alkyl group which may have a substituent, or a halogen atom, and preferably represents a hydrogen atom, a methyl group, a hydroxymethyl group or an acetoxymethyl group.

  The repeating unit having a lactone group usually has an optical isomer, but any optical isomer may be used.

  As for the content rate of the repeating unit which has a lactone group, 15-60 mol% is preferable with respect to all the repeating units in resin, More preferably, it is 20-50 mol%, More preferably, it is 30-50 mol%.

  In order to enhance the effect of the present invention, two or more lactone repeating units selected from general formula (II) can be used in combination. When using together, it is preferable to select and use 2 or more types from the lactone repeating unit whose n is 1 among general formula (II). Moreover, it is also preferable to use together the lactone repeating unit whose Ab is a single bond in General formula (AII), and the lactone repeating unit whose n is 1 among General formula (II).

  It is preferable that resin (A) has a repeating unit other than general formula (II-1) and (III) which has a hydroxyl group or a cyano group. This improves the substrate adhesion and developer compatibility. The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group, and preferably has no acid-decomposable group. The alicyclic hydrocarbon structure in the alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group is preferably an adamantyl group, a diamantyl group, or a norbornyl group. Preferred examples of the alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group include a monohydroxyadamantyl group, a dihydroxyadamantyl group, a monohydroxydiamantyl group, a dihydroxyadamantyl group, and a norbornyl group substituted with a cyano group.

Examples of the repeating unit having the atomic group include repeating units represented by the following general formulas (AIIa) to (AIId).

In the general formulas (AIIa) to (AIId),
R ₁ c represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom, a hydroxyl group or a cyano group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group or a cyano group. Preferably, one or two of R ₂ c to R ₄ c are a hydroxyl group and the remaining is a hydrogen atom. In general formula (VIIa), more preferably, _two of R ₂ c to R ₄ c are hydroxyl groups and the remaining are hydrogen atoms.

The content of the repeating unit having a hydroxyl group or a cyano group is preferably from 5 to 40 mol%, more preferably from 5 to 30 mol%, still more preferably from 10 to 25 mol%, based on all repeating units in the resin (A).
Specific examples of the repeating unit having a hydroxyl group or a cyano group are given below, but the present invention is not limited thereto.

  The resin used in the composition of the present invention may have a repeating unit having an alkali-soluble group. Examples of the alkali-soluble group include a carboxyl group, a sulfonamide group, a sulfonylimide group, a bisulsulfonylimide group, and an aliphatic alcohol (for example, hexafluoroisopropanol group) substituted with an electron withdrawing group at the α-position. It is more preferable to have a repeating unit. By containing the repeating unit having an alkali-soluble group, the resolution in contact hole applications is increased. The repeating unit having an alkali-soluble group includes a repeating unit in which an alkali-soluble group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or an alkali in the main chain of the resin through a linking group. Either a repeating unit to which a soluble group is bonded, or a polymerization initiator or chain transfer agent having an alkali-soluble group is used at the time of polymerization and introduced at the end of the polymer chain, and the linking group is monocyclic or polycyclic. It may have a cyclic hydrocarbon structure. Particularly preferred are repeating units of acrylic acid or methacrylic acid.

As for the content rate of the repeating unit which has an alkali-soluble group, 0-20 mol% is preferable with respect to all the repeating units in resin (A), More preferably, it is 3-15 mol%, More preferably, it is 5-10 mol%.
Specific examples of the repeating unit having an alkali-soluble group are shown below, but the present invention is not limited thereto. In specific examples, Rx represents H, CH ₃ , CH ₂ OH, or CF ₃ .

The resin (A) of the present invention preferably further has a repeating unit that has an alicyclic hydrocarbon structure having no polar group and does not exhibit acid decomposability. This can reduce the elution of low molecular components from the resist film to the immersion liquid during immersion exposure. An example of such a repeating unit is a repeating unit represented by the general formula (4).

In general formula (4), R ₅ represents a hydrocarbon group having at least one cyclic structure and having neither a hydroxyl group nor a cyano group.
Ra represents a hydrogen atom, an alkyl group which may have a substituent, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group. Ra is preferably a hydrogen atom, a methyl group, a hydroxymethyl group or a trifluoromethyl group, particularly preferably a hydrogen atom or a methyl group.

The cyclic structure possessed by R ₅ includes a monocyclic hydrocarbon group and a polycyclic hydrocarbon group. Examples of the monocyclic hydrocarbon group include a cycloalkyl group having 3 to 12 carbon atoms and a cycloalkenyl group having 3 to 12 carbon atoms. A preferable monocyclic hydrocarbon group is a monocyclic hydrocarbon group having 3 to 7 carbon atoms.

  The polycyclic hydrocarbon group includes a ring assembly hydrocarbon group and a bridged cyclic hydrocarbon group. Examples of the bridged cyclic hydrocarbon ring include a bicyclic hydrocarbon ring, a tricyclic hydrocarbon ring, and a tetracyclic hydrocarbon ring. The bridged cyclic hydrocarbon ring also includes a condensed cyclic hydrocarbon ring (for example, a condensed ring in which a plurality of 5- to 8-membered cycloalkane rings are condensed). Preferred examples of the bridged cyclic hydrocarbon ring include a norbornyl group and an adamantyl group.

  These alicyclic hydrocarbon groups may have a substituent, and preferred substituents include a halogen atom, an alkyl group, a hydroxyl group protected with a protecting group, an amino group protected with a protecting group, and the like. It is done. Preferred halogen atoms include bromine, chlorine and fluorine atoms, and preferred alkyl groups include methyl, ethyl, butyl and t-butyl groups. The above alkyl group may further have a substituent, and the substituent that may further have a halogen atom, an alkyl group, a hydroxyl group protected with a protecting group, an amino protected with a protecting group The group can be mentioned.

  Examples of the protecting group include an alkyl group, a cycloalkyl group, an aralkyl group, a substituted methyl group, a substituted ethyl group, an alkoxycarbonyl group, and an aralkyloxycarbonyl group. Preferred alkyl groups include alkyl groups having 1 to 4 carbon atoms, preferred substituted methyl groups include methoxymethyl, methoxythiomethyl, benzyloxymethyl, t-butoxymethyl, 2-methoxyethoxymethyl groups, and preferred substituted ethyl groups. 1-ethoxyethyl, 1-methyl-1-methoxyethyl, preferred acyl groups include formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, pivaloyl groups, etc., aliphatic acyl groups having 1 to 6 carbon atoms, alkoxycarbonyl Examples of the group include an alkoxycarbonyl group having 1 to 4 carbon atoms.

The content of the repeating unit having an alicyclic hydrocarbon structure having no polar group and not exhibiting acid decomposability is preferably 0 to 40 mol%, more preferably, based on all repeating units in the resin (A). 0 to 20 mol%.
Specific examples of the repeating unit having an alicyclic hydrocarbon structure having no polar group and not exhibiting acid decomposability are shown below, but the present invention is not limited thereto. In the formula, Ra represents H, CH ₃ , CH ₂ OH, or CF ₃ .

  The resin (A) used in the composition of the present invention has, in addition to the above repeating structural units, dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and resolving power that is a general necessary characteristic of resist. It can have various repeating structural units for the purpose of adjusting heat resistance, sensitivity and the like.

  Examples of such a repeating structural unit include, but are not limited to, repeating structural units corresponding to the following monomers.

  Thereby, performance required for the resin used in the composition of the present invention, in particular, (1) solubility in coating solvent, (2) film-forming property (glass transition point), (3) alkali developability, (4 Fine adjustments such as () film slippage (selection of hydrophilicity / hydrophobicity, alkali-soluble group), (5) adhesion of unexposed part to substrate, (6) dry etching resistance, etc. are possible.

  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 (A) used in the composition 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 required performance of the resist. It is appropriately set to adjust the resolving power, heat resistance, sensitivity and the like.

When the composition of the present invention is for ArF exposure, the resin (A) used in the composition of the present invention preferably has no aromatic group from the viewpoint of transparency to ArF light.
Moreover, it is preferable that resin (A) does not contain a fluorine atom and a silicon atom from a compatible viewpoint with hydrophobic resin (HR) mentioned above.

  The resin (A) used in the actinic ray-sensitive or radiation-sensitive resin composition of the present invention is preferably one in which all repeating units are composed of (meth) acrylate repeating units. In this case, all of the repeating units are methacrylate repeating units, all of the repeating units are acrylate repeating units, or all of the repeating units are methacrylate repeating units and acrylate repeating units. Although it can be used, the acrylate-based repeating unit is preferably 50 mol% or less of the total repeating units. More preferably, the (meth) acrylate repeating unit having an acid-decomposable group is 20 to 50 mol%, the (meth) acrylate repeating unit having a lactone group is 20 to 50 mol%, and the alicyclic ring is substituted with a hydroxyl group or a cyano group. It is a copolymer containing 5 to 30 mol% of a (meth) acrylate-based repeating unit having a hydrocarbon structure and further 0 to 20 mol% of another (meth) acrylate-based repeating unit.

  The resin (A) of the present invention can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and the polymerization is performed by heating, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as the solvent used in the composition of the present invention. Thereby, generation | occurrence | production of the particle at the time of a preservation | save can be suppressed.

  The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred initiators include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. 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 5 to 50% by mass, preferably 10 to 30% by mass. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 60-100 ° C.

  The weight average molecular weight of the resin (A) of the present invention is preferably 1,000 to 200,000, more preferably 2,000 to 20,000, still more preferably 3, as a polystyrene conversion value by GPC method. 000 to 15,000, particularly preferably 3,000 to 10,000. By setting the weight average molecular weight within the above range, it is possible to prevent heat resistance improvement, dry etching resistance deterioration prevention, developability deterioration, film formation deterioration due to increased viscosity, and the like.

  The dispersity (molecular weight distribution) is usually 1 to 3, preferably 1 to 2.6, more preferably 1 to 2, and particularly preferably 1.4 to 2.0. The smaller the molecular weight distribution, the better the resolution and the resist shape, and the smoother the side wall of the resist pattern, the better the roughness.

In the composition of the present invention, the resin (A) may be used alone or in combination.
As for the compounding ratio in the whole composition of resin (A), 50-99.5 mass% is preferable in a total solid, More preferably, it is 60-99.0 mass%.

[3] Compound (B) that generates acid upon irradiation with actinic rays or radiation
The composition of the present invention may contain a compound that generates an acid upon irradiation with actinic rays or radiation (hereinafter also referred to as “acid generator”).

Although it will not specifically limit as an acid generator if it is a well-known thing, Preferably the compound represented by the following general formula (ZI), (ZII), (ZIII) can be mentioned.

In the general formula (ZI),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
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 members to groups of R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

Z ⁻ represents a non-nucleophilic anion (an anion having an extremely low ability to cause a nucleophilic reaction).
Examples of Z ⁻ include a sulfonate anion (an aliphatic sulfonate anion, an aromatic sulfonate anion, a camphor sulfonate anion, etc.), a carboxylate anion (an aliphatic carboxylate anion, an aromatic carboxylate anion, an aralkyl carboxylate anion). Etc.), sulfonylimide anion, bis (alkylsulfonyl) imide anion, tris (alkylsulfonyl) methide anion and the like.

  The aliphatic moiety in the aliphatic sulfonate anion and the aliphatic carboxylate anion may be an alkyl group or a cycloalkyl group, preferably a linear or branched alkyl group having 1 to 30 carbon atoms and a carbon number. 3-30 cycloalkyl groups are mentioned.

  The aromatic group in the aromatic sulfonate anion and aromatic carboxylate 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 mentioned above may have a substituent. Specific examples thereof include nitro groups, halogen atoms such as fluorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably having 1 to 15 carbon atoms), cycloalkyl groups (preferably having 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 2 to 2 carbon atoms). 7), an alkylthio group (preferably 1 to 15 carbon atoms), an alkylsulfonyl group (preferably 1 to 15 carbon atoms), an alkyliminosulfonyl group (preferably 2 to 15 carbon atoms), an aryloxysulfonyl group (preferably carbon) Number 6-20), alkylaryloxysulfonyl group (preferably C7-20), cycloalkylary Examples thereof include an oxysulfonyl group (preferably having 10 to 20 carbon atoms), an alkyloxyalkyloxy group (preferably having 5 to 20 carbon atoms), a cycloalkylalkyloxyalkyloxy group (preferably having 8 to 20 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.

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 naphthylbutyl group.
Examples of the sulfonylimide anion include saccharin anion.

The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methide anion is preferably an alkyl group having 1 to 5 carbon atoms. Examples of substituents for these alkyl groups include halogen atoms, alkyl groups substituted with halogen atoms, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, cycloalkylaryloxysulfonyl groups, and the like. A fluorine atom or an alkyl group substituted with a fluorine atom is preferred.
Examples of other Z ⁻ include fluorinated phosphorus, fluorinated boron, and fluorinated antimony.

Z ⁻ includes an aliphatic sulfonate anion substituted with at least α-position of sulfonic acid with a fluorine atom, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group substituted with a fluorine atom. Bis (alkylsulfonyl) imide anions and tris (alkylsulfonyl) methide anions in which the alkyl group is substituted with a fluorine atom are preferred. The non-nucleophilic anion is more preferably a perfluoroaliphatic sulfonate anion (more preferably 4 to 8 carbon atoms), a benzenesulfonate anion having a fluorine atom, still more preferably a nonafluorobutanesulfonate anion, or perfluorooctane. A sulfonate anion, a pentafluorobenzenesulfonate anion, and a 3,5-bis (trifluoromethyl) benzenesulfonate anion.
From the viewpoint of acid strength, the pKa of the generated acid is preferably −1 or less in order to improve sensitivity.

Examples of the organic group for R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include an aryl group (preferably having 6 to 15 carbon atoms), a linear or branched alkyl group (preferably having 1 to 15 carbon atoms), and a cycloalkyl group (3 carbon atoms). ~ 15 are preferred).

The alkyl group or cycloalkyl group as R _201, R ₂₀₂ and R _203, e.g., a methyl group, an ethyl group, a propyl group, n- butyl group, sec- butyl group, t- butyl group, cyclopropyl group, cyclobutyl Group, cyclohexyl group and the like. The alkyl group and the cycloalkyl group may have a substituent, and examples of the substituent include the same groups as the substituents that the aryl group shown below may have.

Of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ , at least one is preferably an aryl group, more preferably all three are aryl groups. As the aryl group, in addition to a phenyl group, a naphthyl group, and the like, a heteroaryl group such as an indole residue and a pyrrole residue can be used. These aryl groups may further have a substituent. Examples of the substituent include halogen atoms such as nitro groups and fluorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably having 1 to 15 carbon atoms), cycloalkyl groups (preferably having 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 2 to 2 carbon atoms). 7) and the like, but are not limited thereto.

Two selected from R ₂₀₁ , R ₂₀₂ and R ₂₀₃ may be bonded via a single bond or a linking group. Examples of the linking group include an alkylene group (preferably having 1 to 3 carbon atoms), —O—, —S—, —CO—, —SO ₂ — and the like, but are not limited thereto.

Preferred structures when at least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is not an aryl group include paragraphs 0047 and 0048 of JP-A-2004-233661, paragraphs 0040 to 0046 of JP-A-2003-35948, Compounds exemplified as formulas (I-1) to (I-70) in US2003 / 0224288A1, and formulas (IA-1) to (IA-54), formula (IB-) in US2003 / 0077540A1 Examples thereof include cationic structures such as compounds exemplified as 1) to (IB-24).

In particular, when at least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is not an aryl group, the following embodiment (1) or (2) is particularly preferable.

(1) At least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ has a structure represented by Ar—CO—X—, and the remaining group is a linear or branched alkyl group or a cycloalkyl group. If. At this time, when there are two remaining groups, two linear or branched alkyl groups or cycloalkyl groups may be bonded to each other to form a ring structure.

Here, Ar represents an aryl group which may have a substituent, and specifically, is the same as the aryl group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ . A phenyl group which may have a substituent is preferable.

  X represents an alkylene group which may have a substituent. Specifically, it is an alkylene group having 1 to 6 carbon atoms. Preferably it is a C1-C3 linear or branched alkylene group.

  The remaining linear or branched alkyl group or cycloalkyl group preferably has 1 to 6 carbon atoms. These atomic groups may further have a substituent. Moreover, when the remaining groups are two, it is preferable that they are bonded to each other to form a ring structure (preferably a 5- to 7-membered ring).

(2) one or two of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ are an aryl group which may have a substituent, and the remaining group is a linear or branched alkyl group or a cycloalkyl group; If there is.

At this time, as the aryl group, specifically, the same as the aryl group of R _201, R ₂₀₂ and R _203, a phenyl group or a naphthyl group is preferable. The aryl group preferably has any one of a hydroxyl group, an alkoxy group, and an alkyl group as a substituent. More preferably, it is a C1-C12 alkoxy group as a substituent, More preferably, it is a C1-C6 alkoxy group.

  The remaining linear or branched alkyl group or cycloalkyl group preferably has 1 to 6 carbon atoms. These atomic groups may further have a substituent. When the remaining groups are two, the two may be bonded to each other to form a ring structure.

In general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group or a cycloalkyl group.
Aryl group, alkyl group of R ₂₀₄ to R _207, the cycloalkyl group, aryl group R ₂₀₁ to R ₂₀₃ in the above compound (ZI), an alkyl group, an aryl group described as a cycloalkyl group, an alkyl group, a cycloalkyl It is the same as the alkyl group.

Aryl group, alkyl group of R ₂₀₄ to R _207, cycloalkyl groups may have a substituent. Examples of the substituent include those that the aryl group, alkyl group, and cycloalkyl group of R _{201 to} R ₂₀₃ in the above-described compound (ZI) may have.

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

The acid generator (B) that can be used in the composition of the present invention is represented by the general formula (IV) as one form.

In the formula (IV), X ⁺ represents an organic counter ion, and R represents a hydrogen atom or an organic group.
R is preferably an organic group having 1 to 40 carbon atoms, more preferably an organic group having 3 to 20 carbon atoms, and most preferably an organic group represented by the following formula (V).

The organic group for R may have one or more carbon atoms, and preferably, the atom bonded to the oxygen atom in the ester bond represented by the general formula (IV) is a carbon atom, such as an alkyl group, Examples include a cycloalkyl group, an aryl group, an aralkyl group, and a group having a lactone structure, and the chain may have a hetero atom such as an oxygen atom or a sulfur atom. These may have each other as a substituent, and may have a substituent such as a hydroxyl group, an acyl group, an acyloxy group, an oxy group (═O), or a halogen atom.

  In the formula (V), Rc represents a monocyclic or polycyclic organic group having 3 to 30 carbon atoms which may contain a cyclic ether, a cyclic thioether, a cyclic ketone, a cyclic carbonate, a lactone, or a lactam structure. Y is a hydroxyl group, a halogen atom, a cyano group, a carboxyl group, a hydrocarbon group having 1 to 10 carbon atoms, a hydroxyalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an acyl having 1 to 10 carbon atoms. Group, an alkoxycarbonyl group having 2 to 10 carbon atoms, an acyloxy group having 2 to 10 carbon atoms, an alkoxyalkyl group having 2 to 10 carbon atoms, and a halogenated alkyl group having 1 to 8 carbon atoms. When m = 0 to 6 and there are a plurality of Y, they may be the same as or different from each other. n = 0-10.

The total number of carbon atoms constituting the R group represented by formula (IV) is preferably 40 or less.
n = 0 to 3 is preferable, and Rc is preferably a monocyclic or polycyclic organic group having 7 to 16.

  The molecular weight of the compound represented by the general formula (IV) is generally 300 to 1000, preferably 400 to 800, and more preferably 500 to 700.

Examples of the organic counter ion of X ⁺ include a sulfonium cation and an iodonium cation.
In the compound of the general formula (IV), as a preferable form, a compound represented by the general formula (Z _SC1 ) or the general formula (Z _IC1 ) can be mentioned.

In the general formula (Z _SC1 ), the definition and preferred range of R are the same as those in the general formula (IV).

R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.

Specific examples of the organic group of R _201, R ₂₀₂ and R _203, such as a preferred embodiment is the same as R _201, R ₂₀₂ and R ₂₀₃ in formula (ZI).

A compound having a plurality of structures represented by the general formula (Z _SC1 ) may also be used. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (Z _SC1), bound to at least one of R ₂₀₁ to R ₂₀₃ of another compound represented by the general formula (Z _SC1) It may be a compound having a structure.

In the general formula (Z _IC1 )
The definition and preferred range of R are the same as those defined in general formula (IV).
_R204 and _R205 each independently represents an aryl group, an alkyl group or a cycloalkyl group.
Aryl groups R ₂₀₄ and R _205, Examples and preferred embodiments of the alkyl or cycloalkyl group has been described as the aryl group, alkyl group or cycloalkyl group of R ₂₀₄ to R ₂₀₅ in the general formula (ZII) It is the same as that.

Examples of the acid generator further 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. Examples of the aryl group include a benzene ring, a naphthalene ring, a phenanthrene ring, and an anthracene ring.

R ₂₀₈ , R ₂₀₉ and R ₂₁₀ each independently represents an alkyl group, a cycloalkyl group or an aryl group. As an alkyl group and a cycloalkyl group, a C1-C15 linear or branched alkyl group and a C3-C15 cycloalkyl group are preferable, for example, a methyl group, an ethyl group, a propyl group, n-butyl group, Examples thereof include a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group. The aryl group is the same as the aryl group that Ar3 and Ar4 may have.

A represents an alkylene group, an alkenylene group or an arylene group. As an alkylene group, a C1-C6 alkylene group is preferable, More preferably, it is a C1-C3 linear or branched alkylene group. Arylene groups include benzene-1,4-diyl, naphthalene-1,8-diyl, anthracene-1,4-diyl and the like.
Among acid generators, particularly preferred examples are given below.

Specific examples of the compound represented by the general formula (IV) are given 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 composition is preferably 0.1 to 25% by mass, more preferably 0.5 to 20% by mass, and still more preferably 1 to 15% by mass, based on the total solid content of the composition. %.

[4] Solvent (C)
Solvents that can be used in preparing the composition of the present invention by dissolving the above-described components include, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate, alkyl alkoxypropionate. And organic solvents such as cyclic lactones (preferably having 4 to 10 carbon atoms), monoketone compounds which may contain rings (preferably having 4 to 10 carbon atoms), alkylene carbonates, alkyl alkoxyacetates and alkyl pyruvates. it can.

  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 include β-propiolactone, β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone, β-methyl-γ-butyrolactone, γ-valerolactone, γ-caprolactone, and γ-octano. Preferred are iclactone and α-hydroxy-γ-butyrolactone.

  Examples of the monoketone compound 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-hexen-2-one 3-penten-2-one, cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone, 2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopentanone, cyclohexanone, 3- Methylcyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2,2-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone, 2-methylcycloheptanone, 3-methyl Preferred is cycloheptanone.

  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.

  As the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group, the above-described exemplary compounds can be selected as appropriate, but as the solvent containing a hydroxyl group, alkylene glycol monoalkyl ether, alkyl lactate, etc. are preferable, propylene glycol monomethyl ether, More preferred is ethyl lactate. As the solvent not containing a hydroxyl group, alkylene glycol monoalkyl ether acetate, alkyl alkoxypropionate, a monoketone compound which may contain a ring, cyclic lactone, alkyl acetate, etc. are preferable, and among these, propylene glycol monomethyl ether Acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone and butyl acetate are particularly preferred, and propylene glycol monomethyl ether acetate, ethyl ethoxypropionate and 2-heptanone are most preferred.

  The mixing ratio (mass) 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 mass or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.

  The solvent is preferably a mixed solvent of two or more containing propylene glycol monomethyl ether acetate.

[5] Basic Compound The composition of the present invention preferably contains a basic compound in order to reduce the change in performance over time from exposure to heating.
Preferred examples of the basic compound include compounds having structures represented by the following formulas (A) to (E).

In general formulas (A) and (E),
R ²⁰⁰ , R ²⁰¹ and R ²⁰² may be the same or different, and are a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (having a carbon number). 6-20), wherein R ²⁰¹ and R ²⁰² may combine with each other to form a ring. R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represents an alkyl group having 1 to 20 carbon atoms.

About the said alkyl group, as an alkyl group which has a substituent, a C1-C20 aminoalkyl group, a C1-C20 hydroxyalkyl group, or a C1-C20 cyanoalkyl group is preferable.
The alkyl groups in the general formulas (A) and (E) are more preferably unsubstituted.

  Preferred compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, piperidine and the like, and more preferred compounds include imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate Examples thereof include a compound having a structure, a trialkylamine structure, an aniline structure or a pyridine structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, and an aniline derivative having a hydroxyl group and / or an ether bond.

  Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole, and 2-phenylbenzimidazole. Examples of the compound having a diazabicyclo structure include 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] non-5-ene, and 1,8-diazabicyclo [5,4,0. ] Undecar 7-ene etc. are mentioned. Examples of the compound having an onium hydroxide structure include tetrabutylammonium hydroxide, triarylsulfonium hydroxide, phenacylsulfonium hydroxide, sulfonium hydroxide having a 2-oxoalkyl group, specifically, triphenylsulfonium hydroxide, tris ( and t-butylphenyl) sulfonium hydroxide, bis (t-butylphenyl) iodonium hydroxide, phenacylthiophenium hydroxide, 2-oxopropylthiophenium hydroxide, and the like. As the compound having an onium carboxylate structure, an anion portion of the compound having an onium hydroxide structure is converted to a carboxylate, and examples thereof include acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine and tri (n-octyl) amine. Examples of the aniline compound include 2,6-diisopropylaniline, N, N-dimethylaniline, N, N-dibutylaniline, N, N-dihexylaniline and the like. Examples of the alkylamine derivative having a hydroxyl group and / or an ether bond include ethanolamine, diethanolamine, triethanolamine, N-phenyldiethanolamine, and tris (methoxyethoxyethyl) amine. Examples of aniline derivatives having a hydroxyl group and / or an ether bond include N, N-bis (hydroxyethyl) aniline.

  Preferred examples of the basic compound further include an amine compound having a phenoxy group, an ammonium salt compound having a phenoxy group, an amine compound having a sulfonic acid ester group, and an ammonium salt compound having a sulfonic acid ester group.

The amine compound having a phenoxy group, the ammonium salt compound having a phenoxy group, the amine compound having a sulfonate group, and the ammonium salt compound having a sulfonate group have at least one alkyl group bonded to a nitrogen atom. Is preferred. The alkyl chain preferably has an oxygen atom and an oxyalkylene group is formed. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. -CH ₂ CH ₂ O Among the oxyalkylene group _{-, - CH (CH 3)} CH 2 O- or -CH ₂ CH ₂ CH ₂ O- structure is preferred.

Specific examples of the amine compound having a phenoxy group, the ammonium salt compound having a phenoxy group, the amine compound having a sulfonic acid ester group, and the ammonium salt compound having a sulfonic acid ester group are exemplified in [0066] of US2007 / 0224539A. Examples thereof include, but are not limited to, compounds (C1-1) to (C3-3).
These basic compounds are used alone or in combination of two or more.

  The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of the total solid of the composition of this invention, Preferably it is 0.01-5 mass%.

  The use ratio of the acid generator and the basic compound in the composition is preferably acid generator / basic compound (molar ratio) = 2.5 to 300. In other words, the molar ratio is preferably 2.5 or more from the viewpoint of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing the reduction in resolution due to the thickening of the resist pattern over time until post-exposure heat treatment. The acid generator / basic compound (molar ratio) is more preferably 5.0 to 200, still more preferably 7.0 to 150.

[6] Surfactant The composition of the present invention preferably further contains a surfactant, and a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant, silicon-based surfactant, fluorine atom and It is more preferable to contain any one or two or more of surfactants having both silicon atoms.

  When the composition of the present invention contains the above surfactant, it is possible to provide a resist pattern with good sensitivity and resolution and less adhesion and development defects.

  Examples of commercially available surfactants that can be used include F-top EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431, 4430 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189 , F113, F110, F177, F120, R08 (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Manufactured by Troy Chemical Co., Ltd.), GF-300, GF-150 (manufactured by Toagosei Chemical Co., Ltd.), Surflon S-393 (manufactured by Seimi Chemical Co., Ltd.), F-top EF121, EF122A, EF122B, RF122C, EF125M , EF135M, EF351, EF352, EF801, EF802, F601 (manufactured by Gemco), PF636, PF656, PF6320, PF6520 (manufactured by OMNOVA), FTX-204G, 208G, 218G, 230G, 204D, 208D, 212D, 218D, 222D (manufactured by Neos) 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 a method described in the vicinity of [0015] to [0018] of JP-A-2002-90991. The polymer having a fluoroaliphatic group may be a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate.

As commercially available surfactants corresponding to the above, Megafac F178, F-470, F-473, F-475, F-476, F-472 (manufactured by Dainippon Ink & Chemicals, Inc.) can be exemplified. . 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 ₃ F ₇ group and (poly (oxy) And a copolymer of (ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate).

  In the present invention, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. Specifically, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether and polyoxyethylene stearyl ether, polyoxyethylene alkyl aryl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether, polyoxyethylene Polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan fatty acid esters such as sorbitan monostearate, sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate , Polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene It can be mentioned nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as sorbitan tristearate.

These surfactants may be used alone or in several combinations.
The amount of the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total amount of the composition of the present invention (excluding the solvent).

[7] Carboxylic acid onium salt The composition of the present invention may contain a carboxylic acid onium salt. As the carboxylic acid onium salt, an iodonium salt and a sulfonium salt are preferable. As the 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.

  The content of the carboxylic acid onium salt in the composition is generally 0.1 to 20% by mass, preferably 0.5 to 10% by mass, more preferably 1%, based on the total solid content of the composition of the present invention. -7% by mass.

[8] Dissolution-inhibiting compound The composition of the present invention comprises a dissolution-inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as “dissolution-inhibiting compound”), which decomposes by the action of an acid to increase the solubility in an alkaline developer. You may contain. The dissolution inhibiting compound contains an acid-decomposable group, such as a cholic acid derivative containing an acid-decomposable group described in Proceeding of SPIE, 2724,355 (1996), in order not to lower the permeability of 220 nm or less. Preferred are alicyclic or aliphatic compounds. Examples of the acid-decomposable group and alicyclic structure are the same as those described for the component (A) resin.

  When the composition of the present invention is exposed with a KrF excimer laser or irradiated with an electron beam, the dissolution inhibiting compound contains a structure in which the phenolic hydroxyl group of the phenol compound is substituted with an acid-decomposable group. preferable. As a phenol compound, what contains 1-9 phenol frame | skeleton is preferable, More preferably, it contains 2-6 pieces.

The addition amount of the dissolution inhibiting compound is preferably 3 to 50% by mass, more preferably 5 to 40% by mass, based on the total solid content of the composition of the present invention.
Specific examples of the dissolution inhibiting compound are shown below, but the present invention is not limited thereto.

[9] Antioxidant The composition of the present invention may contain an antioxidant.
As the antioxidant, it is preferable to use a phenolic antioxidant or an antioxidant composed of an organic acid derivative.
As these specific compounds, for example, compounds disclosed in paragraphs 0130 to 0133 of JP-A-2006-276688 can be used as appropriate.
[10] Other additives In the composition of the present invention, a dye, a plasticizer, a photosensitizer, a light absorber, and a compound that promotes solubility in a developing solution (for example, a molecular weight of 1000 or less) as necessary. A phenol compound, an alicyclic group 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.

<Pattern formation method>
The composition of the present invention is preferably used in a film thickness of 30 to 250 nm, more preferably in a film thickness of 30 to 200 nm, from the viewpoint of improving resolution. Such a film thickness can be obtained by setting the solid content concentration in the composition of the present invention to an appropriate range to give an appropriate viscosity and improving the coating property and film forming property.
1-10 mass%, More preferably, it is 1-8.0 mass%, More preferably, it is 1.0-6.0 mass%.

  The composition of the present invention is used by dissolving the above-described components in a predetermined organic solvent, preferably the mixed solvent, filtering the solution, and applying the solution on a predetermined support as follows. The pore size of the filter used for filter filtration is preferably 0.1 μm or less, more preferably 0.05 μm or less, and still more preferably 0.03 μm or less, and those made of polytetrafluoroethylene, polyethylene, or nylon are preferable.

For example, an actinic ray-sensitive or radiation-sensitive resin composition is applied to a substrate (eg, silicon / silicon dioxide coating) used for manufacturing a precision integrated circuit element by an appropriate application method such as a spinner or a coater. Dry to form a film.
The film is irradiated with actinic rays or radiation through a predetermined mask, preferably baked (heated), developed and rinsed. Thereby, a good pattern can be obtained.

Examples of the actinic ray or radiation include infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-ray, electron beam, etc., preferably 250 nm or less, more preferably 220 nm or less, particularly Preferably, far ultraviolet light having a wavelength of 1 to 200 nm, specifically KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-ray, electron beam, etc., ArF excimer Laser, F ₂ excimer laser, EUV (13 nm), and electron beam are preferable.

Before forming the film, an antireflection film may be previously coated on the substrate.
As the antireflection film, any of an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, and amorphous silicon, and an organic film type made of a light absorber and a polymer material can be used. In addition, as the organic antireflection film, commercially available organic antireflection films such as DUV30 series, DUV-40 series manufactured by Brewer Science, AR-2, AR-3, AR-5 manufactured by Shipley, etc. may be used. it can.

As the alkaline developer in the development step, a quaternary ammonium salt typified by tetramethylammonium hydroxide is usually used. In addition, inorganic alkali, primary amine, secondary amine, tertiary amine, alcohol amine are also used. An aqueous alkali solution such as a cyclic amine can also be used.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.

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.
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.

  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 further more concretely, this invention is not limited to a following example.
<Resin (A)>
Below, the monomer corresponding to the repeating unit used for the synthesis | combination of resin (A) used for the present Example is shown.

Synthesis Example 1: (Synthesis of Resin (A-1))
Under a nitrogen stream, 8.8 g of cyclohexanone was placed in a three-necked flask and heated to 80 ° C. To this, (LM-1) 8.5 g, (IM-1) 8.8 g, (PM-4) 4.7 g, and polymerization initiator V-60 (manufactured by Wako Pure Chemical Industries, Ltd.) at 13 mol% with respect to the monomer were cyclohexanone. The solution dissolved in 79 g was added dropwise over 6 hours. After completion of dropping, the reaction was further carried out at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then added dropwise to a mixed solution of 900 m of methanol / 100 ml of water over 20 minutes. The precipitated powder was collected by filtration and dried to obtain 18 g of Resin (A-1). The composition ratio of the obtained resin was 49/11/40, the weight average molecular weight was 8200 in terms of standard polystyrene, and the dispersity (Mw / Mn) was 1.53.
Resins (A-2) to (A-20) were synthesized in the same manner as in Synthesis Example 1. The structure is shown below.

The following (Table 1) shows the monomers used for the synthesis, the monomer ratio, the weight average molecular weight, and the degree of dispersion for the resins (A-1) to (A-20). The monomer ratio corresponds in order from the left of each monomer.

<Resin (HR)>
The structures of resins (HR-1) to (HR-20) used in this example and (HR-21) to (HR-22) used in comparative examples are shown below. The monomer ratio, weight average molecular weight, and dispersity of each resin are shown in Table 2.

(Examples 1-20 and Comparative Examples 1-2)
The components shown in Table 3 below were dissolved in a solvent to prepare a solution having a solid content concentration of 4.5%, and this was filtered through a polyethylene filter having a pore size of 0.03 μm to prepare a positive resist solution. The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 4 below.

  The compounds corresponding to the abbreviations in Table 3 are the compounds shown below.

<Acid generator>

<Basic compound>
N-1: N, N-dibutylaniline N-2: trioctylamine N-3: N, N-dihydroxyethylaniline N-4: 2,4,5-triphenylimidazole N-5: 2,6-diisopropyl Aniline N-6: Hydroxyantipyrine N-7: Trismethoxymethoxyethylamine N-8: Triethanolamine <Additive>

<Surfactant>
W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
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: KH-20 (Asahi Kasei Corporation)
W-6: PF6320 (made by OMNOVA)
W-7: PF6520 (made by OMNOVA)
<Solvent>
Group a SL-1: Propylene glycol monomethyl ether acetate SL-2: Propylene glycol monomethyl ether propionate SL-3: 2-heptanone group b SL-4: Ethyl lactate SL-5: Propylene glycol monomethyl ether SL-6: Cyclohexanone Group c SL-7: γ-butyrolactone SL-8: Propylene carbonate <Resist evaluation>
(Exposure conditions: ArF immersion exposure)
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The positive resist composition prepared thereon was applied and baked at 100 ° C. for 60 seconds to form a resist film having a thickness of 100 nm. The resist film was subjected to pattern exposure using XT1700i (NA 1.2, scan speed 500 mm / s) manufactured by ASML through a 65 nm 1: 1 line and space mask. Ultra pure water was used as the immersion liquid. Immediately after exposure, the film was heated on a hot plate at 100 ° C. for 60 seconds, and then cooled to room temperature. Furthermore, after developing for 30 seconds at 23 ° C. using an aqueous 2.38 mass% tetramethylammonium hydroxide solution, rinsing with pure water for 30 seconds, Postbake was performed at 90 ° C. for 90 seconds to obtain a line pattern.

[LWR]
In the standard resist evaluation, the line pattern finished at 65 nm was observed with a scanning microscope (S9380 manufactured by Hitachi, Ltd.), and the line width was measured at 50 points in the range of the edge of 2 μm in the longitudinal direction of the line pattern. The standard deviation was calculated for 3 and 3σ was calculated.

A smaller value indicates better performance.

[Development defects]
Using a defect inspection device KLA2360 (trade name) manufactured by KLA-Tencor, Inc., setting the pixel size of the defect inspection device to 0.16m and the threshold value to 20, and measuring in random mode, a comparison image The number of development defects extracted per unit area was calculated by detecting the development defects extracted from the differences caused by the pixel unit overlap, and the types of defects were classified from the obtained images. A value of less than 0.5 was evaluated as ◯, a value of less than 0.5 to 0.8 was evaluated as Δ, and a value of 0.8 or more was evaluated as ×. A smaller value indicates better performance.

The results of the above evaluation are shown in Table 4.

  From the results shown in Table 4, it is clear that the positive photosensitive composition of the present invention has a reduced number of remaining water defects, bubble defects, and development residue defects and a good LWR as compared with the conventional one.

Claims (12)

  Containing a resin (HR) containing a repeating unit (a) having a polycyclic structure in the main chain, and the polycyclic structure being decomposed by the action of an acid and having increased solubility in an alkaline developer. An actinic ray-sensitive or radiation-sensitive resin composition.   The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, wherein the repeating unit (a) contains a fluorine atom.   The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, wherein the resin (HR) further contains a repeating unit containing a fluorine atom. The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 3, wherein the repeating unit (a) is represented by the following general formula (I).

Where
R ₁ represents a group that is decomposed by the action of an acid.
R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a fluorine atom, an alkyl group, a cycloalkyl group, an alkoxy group, a group containing a carbonyl group, a group containing a carbonyloxy group, a group containing an oxycarbonyl group, It represents a group containing an ether group, a hydroxyl group, an amide group, or an aryl group. Alkyl group, cycloalkyl group, carbonyl group-containing group, carbonyloxy group-containing group, oxycarbonyl group-containing group, ether group-containing group, amide group, aryl group part or all of hydrogen atoms are fluorine atoms May be substituted. Any _{two of} R ₂ , R ₃ and R ₄ may be linked to form a ring.
n is 0 or 1. further,
(A) a resin that is decomposed by the action of an acid and has increased solubility in an alkaline developer;
5. The actinic ray-sensitive or radiation-sensitive composition according to claim 1, comprising (B) a compound that generates an acid upon irradiation with actinic rays or radiation, and (C) a solvent. Resin composition.   The actinic ray-sensitive or radiation-sensitive resin composition according to claim 5, wherein the resin (A) contains a repeating unit containing a lactone structure. The actinic ray-sensitive or radiation-sensitive resin composition according to claim 6, wherein the repeating unit containing a lactone structure of the resin (A) is a repeating unit represented by the following general formula (II).

In the formula, A represents an ester bond or an amide bond.
R ₀ independently represents an alkylene group, a cycloalkylene group, or a combination thereof when there are a plurality of R ₀ .
Z is independently an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond when there are a plurality of Z.
R ₈ represents a monovalent organic group having a lactone structure.
n is a repeating number and represents an integer of 1 to 5.
R ₇ represents a hydrogen atom, a halogen atom or an alkyl group which may have a substituent.   The actinic ray-sensitive or sensitizing material according to any one of claims 5 to 7, wherein the resin (A) contains a repeating unit containing a monocyclic or polycyclic acid-decomposable group. Radiation resin composition. The actinic ray-sensitive or radiation-sensitive resin composition according to claim 8, wherein the repeating unit containing an acid-decomposable group in the resin (A) is a repeating unit represented by the following general formula (III): object.

In general formula (III),
R ₃ represents a hydrogen atom, a methyl group which may have a substituent, or a group represented by —CH ₂ —R ₉ . R ₉ represents a hydroxyl group or a monovalent organic group.
R ₄ and R ₅ each independently represents an alkyl group (straight or branched) or a cycloalkyl group (monocyclic or polycyclic).
L represents a divalent linking group.
n ₁ is 0 or 1.
P represents a polar group.
p shows the integer of 1-15.   The content rate of resin (HR) is 0.01-10 mass% with respect to the total solid in an actinic-ray-sensitive or radiation-sensitive resin composition, Any one of Claim 1 to 9 characterized by the above-mentioned. 2. The actinic ray-sensitive or radiation-sensitive resin composition according to item 1.   A pattern forming method comprising: forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 10, and exposing and developing the film. .   The pattern forming method according to claim 11, wherein exposure is performed through an immersion liquid.