Resist composition and method for forming resist pattern

Abstract

To provide a resist composition having good sensitivity, CDU suitability, and resolution.SOLUTION: The resist composition contains: a base component (A) whose solubility in a developer changes by the action of an acid; a compound (D01) represented by general formula (d01-1); a compound (D02) represented by general formula (d02-1); and a polymer compound (F01) having a constituent unit (f01) represented by general formula (f01-1) and a constituent unit (f02) represented by general formula (f02-1). Rd01 and Rd02 are each a cyclic group, an alkyl group or an alkenyl group; Mm+ is an m-valent organic cation; R is a hydrogen atom, an alkyl group or a halogenated alkyl group; Vf01 is a divalent linking group; Rf01 is a monovalent organic group containing a fluorine atom; Vf02 is a divalent linking group; nf02 is an integer of 0-2; and Rf02 is an acid-dissociable group.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a resist composition and a method of forming a resist pattern. [Background technology]

[0002] In lithography technology, for example, a process is carried out in which a resist film made of a resist material is formed on a substrate, the resist film is selectively exposed to radiation such as light or an electron beam through a mask having a predetermined pattern formed thereon, and a development process is carried out to form a resist pattern of a predetermined shape in the resist film. A resist material whose exposed portion changes to a property that makes it soluble in a developer is called a positive type, and a resist material whose exposed portion changes to a property that makes it insoluble in a developer is called a negative type.

[0003] In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, the progress of lithography technology has led to rapid progress in miniaturization of patterns. In general, the method of miniaturization of patterns is to shorten the wavelength (high energy) of the exposure light source. Specifically, ultraviolet rays such as g-line and i-line have been used in the past, but currently, mass production of semiconductor elements using KrF excimer lasers and ArF excimer lasers has begun. In addition, electron beams, EUV (extreme ultraviolet rays), X-rays, and the like, which have shorter wavelengths (higher energies) than these excimer lasers, are also being studied. The resist material is required to have lithography properties such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with fine dimensions. As a resist material that satisfies such requirements, a chemically amplified resist composition containing a base component whose solubility in an alkaline developer changes due to the action of an acid and an acid generator component that generates an acid upon exposure is used.

[0004] As one of the methods for improving resolution, a lithography method in which exposure (immersion exposure) is performed by placing a liquid (immersion medium) with a higher refractive index than air between the objective lens of an exposure machine and a sample, known as liquid immersion lithography (hereinafter sometimes referred to as "immersion exposure"), is known. With immersion exposure, even if a light source with the same exposure wavelength is used, it is said that a high resolution similar to that of a light source with a shorter wavelength or a high NA lens is achieved, and there is no decrease in the depth of focus. In addition, immersion exposure can be performed using existing exposure equipment. Therefore, immersion exposure has been used in recent years because it can realize the formation of resist patterns that are low-cost, have high resolution, and are excellent in depth of focus. Immersion exposure is effective in forming all kinds of pattern shapes, and it is also said that it can be combined with super-resolution techniques such as phase shifting and modified illumination. Currently, immersion exposure techniques that use ArF excimer lasers as a light source are being actively researched. As the immersion medium, water is mainly considered.

[0005] In the above-mentioned immersion lithography, in addition to the usual lithography characteristics (sensitivity, resolution, etching resistance, etc.), resist materials that have characteristics corresponding to the immersion lithography technology are required. For example, in immersion lithography, when the resist film comes into contact with the immersion solvent, substances in the resist film dissolve into the immersion solvent (substance elution). Substance elution causes phenomena such as deterioration of the resist layer and changes in the refractive index of the immersion solvent, deteriorating the lithography characteristics. Since the amount of this substance elution is affected by the characteristics of the resist film surface (e.g., hydrophilicity / hydrophobicity), for example, by increasing the hydrophobicity of the resist film surface, substance elution is reduced, improving the lithography characteristics.

[0006] It has been proposed to add a compound containing a fluorine atom to a resist composition used in such immersion exposure. For example, Patent Document 1 discloses a fluorine-containing polymer compound having a structural unit having a fluorine atom and a structural unit containing an acid-dissociable group as a compound containing a fluorine atom to be added to a resist composition. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2013-181126 A Summary of the Invention [Problem to be solved by the invention]

[0008] As lithography technology continues to advance and resist patterns become finer, there is a demand for even higher sensitivity and improved lithography properties. However, in the conventional resist compositions described above, increasing the sensitivity to the exposure light source tends to increase the roughness of the resist pattern, making it difficult to satisfy both of these properties.

[0009] The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a resist composition that is capable of forming a resist pattern that has good sensitivity and reduced roughness, and a method of forming a resist pattern that uses the resist composition. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention employs the following configuration. That is, a first aspect of the present invention is a resist composition that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid, the resist composition comprising: a base component (A) whose solubility in a developer changes due to the action of an acid; a compound (D01) represented by the following general formula (d01-1); a compound (D02) represented by the following general formula (d02-1); and a polymeric compound (F01) having a structural unit (f01) represented by the following general formula (f01-1) and a structural unit (f02) represented by the following general formula (f02-1).

[0011] [ka] [In the formula, Rd 01 and Rd 02 are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. 02 In the formula (d01-2), no fluorine atom is bonded to the carbon atom adjacent to the S atom. Each m is independently an integer of 1 or more, and M m+ are each independently an organic cation having a valence of m.

[0012] [ka] [In the formula, each R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; 01 is a divalent linking group; Rf 01 is a monovalent organic group containing a fluorine atom; Vf 02 is a divalent linking group; nf 02 is an integer from 0 to 2; Rf 02 is an acid-dissociable group.

[0013] A second aspect of the present invention is a method for forming a resist pattern, comprising the steps of forming a resist film on a support using the resist composition related to the first aspect, exposing the resist film, and developing the exposed resist film to form a resist pattern. Effect of the Invention

[0014] EFFECTS OF THE PRESENT DISCLOSURE According to the present invention, it is possible to provide a resist composition that is capable of forming a resist pattern that has good sensitivity and reduced roughness, and a method of forming a resist pattern that uses the resist composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] In this specification and claims, the term "aliphatic" is a relative concept to aromaticity and is defined as meaning a group, compound, etc. that does not have aromaticity. Unless otherwise specified, the term "alkyl group" includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in an alkoxy group. Unless otherwise specified, the term "alkylene group" includes linear, branched and cyclic divalent saturated hydrocarbon groups. The "halogen atom" includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The term "structural unit" refers to a monomer unit that constitutes a polymeric compound (resin, polymer, copolymer). When describing "optionally having a substituent," it means replacing a hydrogen atom (-H) with a monovalent group or a methylene group (-CH 2 -) is replaced with a divalent group. The term "exposure" is intended to include any concept including irradiation with radiation.

[0016] The term "acid-decomposable group" refers to a group having acid decomposability in which at least a part of the bonds in the structure of the acid-decomposable group can be cleaved by the action of an acid. Examples of acid-decomposable groups whose polarity increases under the action of an acid include groups that are decomposed by the action of an acid to generate a polar group. Examples of polar groups include carboxyl groups, hydroxyl groups, amino groups, and sulfo groups (-SO 3 H) etc. More specific examples of the acid-decomposable group include groups in which the polar group is protected with an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).

[0017] The term "acid dissociable group" refers to both (i) a group having acid dissociability in which the bond between the acid dissociable group and an atom adjacent to the acid dissociable group can be cleaved by the action of an acid, and (ii) a group in which a portion of the bond is cleaved by the action of an acid and then a decarboxylation reaction occurs, thereby cleaving the bond between the acid dissociable group and an atom adjacent to the acid dissociable group. The acid dissociable group constituting the acid decomposable group must be a group with lower polarity than the polar group generated by dissociation of the acid dissociable group, and thus, when the acid dissociable group is dissociated by the action of an acid, a polar group with higher polarity than the acid dissociable group is generated, increasing the polarity. As a result, the polarity of the entire (A1) component increases. The increase in polarity relatively changes the solubility in the developer, increasing the solubility when the developer is an alkaline developer, and decreasing the solubility when the developer is an organic developer.

[0018] The "base material component" is an organic compound having a film-forming ability. Organic compounds used as base material components are broadly divided into non-polymers and polymers. As non-polymers, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, the term "low molecular weight compound" refers to a non-polymer having a molecular weight of 500 or more and less than 4000. As polymers, those having a molecular weight of 1000 or more are usually used. Hereinafter, the terms "resin", "polymer compound" and "polymer" refer to a polymer having a molecular weight of 1000 or more. The molecular weight of the polymer is the weight average molecular weight calculated in terms of polystyrene by GPC (gel permeation chromatography).

[0019] The term "derived structural unit" refers to a structural unit formed by cleavage of a multiple bond between carbon atoms, for example, an ethylenic double bond. In the "acrylic acid ester", the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. αx ) is an atom or group other than a hydrogen atom. αx Itaconic acid diesters in which the substituent (R αx It also includes α-hydroxyacrylic esters in which the α-position carbon atom of an acrylic ester is substituted with a hydroxyalkyl group or a group that modifies the hydroxyl group of the acrylic ester. Unless otherwise specified, the carbon atom at the α-position of an acrylic ester refers to the carbon atom to which the carbonyl group of acrylic acid is bonded. Hereinafter, an acrylic ester in which the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent will sometimes be referred to as an α-substituted acrylic ester.

[0020] The term "derivative" refers to a concept that includes compounds in which the hydrogen atom at the α-position of the target compound is replaced with other substituents such as an alkyl group or a halogenated alkyl group, as well as derivatives thereof. Examples of such derivatives include compounds in which the hydrogen atom of the hydroxyl group of a target compound, which may have the hydrogen atom at the α-position replaced with a substituent, is replaced with an organic group; compounds in which the hydrogen atom at the α-position of a target compound, which may have the hydrogen atom at the α-position replaced with a substituent, is bonded with a substituent other than a hydroxyl group, and the like. The α-position refers to the first carbon atom adjacent to the functional group, unless otherwise specified. The substituent that replaces the hydrogen atom at the α-position of hydroxystyrene is R αx The same can be mentioned.

[0021] In the present specification and claims, some structures represented by chemical formulas may have asymmetric carbons, and may have enantiomers or diastereomers. In such cases, a single chemical formula represents all of the isomers. These isomers may be used alone or as a mixture.

[0022] (Resist composition) The resist composition of this embodiment generates an acid upon exposure, and the solubility of the resist composition in a developer changes due to the action of the acid. The resist composition of this embodiment contains a base component (A) (hereinafter also referred to as "component (A)") whose solubility in a developer changes under the action of an acid, a compound (D01) (hereinafter also referred to as "component (D01)") represented by general formula (d01-1), a compound (D02) (hereinafter also referred to as "component (D02)") represented by general formula (d02-1), and a polymeric compound (F01) (hereinafter also referred to as "component (F01)") having a structural unit (f01) represented by general formula (f01-1) and a structural unit (f02) represented by general formula (f02-1).

[0023] When a resist film is formed using the resist composition of this embodiment and selectively exposed to light, an acid is generated in the exposed portion of the resist film, and the solubility of the component (A) in the developer changes due to the action of the acid, while the solubility of the component (A) in the developer does not change in the unexposed portion of the resist film, so that a difference in solubility in the developer occurs between the exposed portion and the unexposed portion of the resist film. Therefore, when the resist film is developed, if the resist composition is a positive type, the exposed portion of the resist film is dissolved and removed to form a positive resist pattern, and if the resist composition is a negative type, the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern. In this specification, a resist composition that dissolves and removes the exposed portion of the resist film to form a positive resist pattern is referred to as a positive resist composition, and a resist composition that dissolves and removes the unexposed portion of the resist film to form a negative resist pattern is referred to as a negative resist composition.

[0024] The resist composition of this embodiment may be a positive resist composition or a negative resist composition. Furthermore, the resist composition of this embodiment may be for use in an alkaline developing process in which an alkaline developer is used in the developing treatment during resist pattern formation, or for use in a solvent developing process in which an organic developer is used in the developing treatment.

[0025] The resist composition of this embodiment has an acid generating ability to generate acid upon exposure. The component (A) may generate acid upon exposure, or an additive component that is formulated separately from the component (A) may generate acid upon exposure. Specifically, the resist composition of the present embodiment is (1) It may contain an acid generator component (B) (hereinafter referred to as “component (B)”) that generates acid upon exposure to light, (2) The component (A) may be a component that generates an acid upon exposure to light, (3) The component (A) is a component that generates an acid upon exposure, and may further contain a component (B). That is, in the cases of the above (2) and (3), the component (A) is a "substrate component that generates an acid upon exposure and whose solubility in a developer changes due to the action of the acid". When the component (A) is a substrate component that generates an acid upon exposure and whose solubility in a developer changes due to the action of the acid, it is preferable that the component (A1) described below is a polymer compound that generates an acid upon exposure and whose solubility in a developer changes due to the action of the acid. As such a polymer compound, a resin having a structural unit that generates an acid upon exposure can be used. As the structural unit that generates an acid upon exposure, known ones can be used.

[0026] Among those described above, the resist composition of the present embodiment is preferably the one in the case of the above (1). That is, a resist composition containing the component (A), the component (D01), the component (D02), the component (F01), and the component (B) is preferable.

[0027] <(A) component> In the resist composition of the present embodiment, the component (A) preferably contains a resin component (A1) (hereinafter also referred to as the "component (A1)") whose solubility in a developer changes due to the action of an acid. By using the component (A1), since the polarity of the substrate component changes before and after exposure, good development contrast can be obtained not only in an alkali development process but also in a solvent development process. As the component (A), at least the component (A1) is used, and other polymer compounds and / or low molecular compounds may be used in combination with the component (A1).

[0028] When an alkaline development process is applied, the base material component containing the component (A1) is poorly soluble in an alkaline developer before exposure, and when an acid is generated from the component (B) by exposure, for example, the polarity increases due to the action of the acid, and the solubility in an alkaline developer increases. Therefore, in forming a resist pattern, when a resist film obtained by applying the resist composition on a support is selectively exposed, the exposed part of the resist film changes from poorly soluble in an alkaline developer to soluble, while the unexposed part of the resist film remains poorly soluble in an alkaline developer, and a positive resist pattern is formed by alkaline development.

[0029] On the other hand, when a solvent development process is applied, the base material component containing the component (A1) is highly soluble in an organic developer before exposure, and when an acid is generated from the component (B) by exposure, for example, the acid increases the polarity and reduces the solubility in an organic developer. Therefore, when a resist film obtained by applying the resist composition to a support is selectively exposed in the formation of a resist pattern, the exposed part of the resist film changes from soluble to poorly soluble in an organic developer, while the unexposed part of the resist film remains soluble, and thus a contrast can be created between the exposed part and the unexposed part by developing with an organic developer, forming a negative resist pattern.

[0030] In the resist composition of this embodiment, the component (A) may use either a single type, or a combination of two or more types.

[0031] Regarding component (A1) The component (A1) is a resin component whose solubility in a developer changes under the action of an acid. The component (A1) preferably has a structural unit (a1) that contains an acid-decomposable group whose polarity increases when acted on by an acid. The component (A1) may contain other structural units in addition to the structural unit (a1), as necessary.

[0032] <Structural unit (a1)> The structural unit (a1) is a structural unit that contains an acid-decomposable group whose polarity increases when acted upon by an acid.

[0033] Examples of the acid-dissociable group include those that have been proposed as acid-dissociable groups in base resins for chemically amplified resist compositions. Specific examples of the acid dissociable group that have been proposed for the base resin of the chemically amplified resist composition include the “acetal type acid dissociable group,” “tertiary alkyl ester type acid dissociable group,” and “tertiary alkyloxycarbonyl acid dissociable group,” which are described below.

[0034] Acetal type acid dissociable group: Among the polar groups, examples of the acid-dissociable group that protects a carboxy group or a hydroxyl group include an acid-dissociable group represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as an "acetal-type acid-dissociable group").

[0035] [ka] [In the formula, Ra' 1 , Ra' 2 is a hydrogen atom or an alkyl group. 3 is a hydrocarbon group, and Ra' 3 Is, Ra' 1 , Ra' 2 may be bonded to any one of the following to form a ring.

[0036] In formula (a1-r-1), Ra' 1 and Ra' 2 At least one of these is preferably a hydrogen atom, and both are more preferably hydrogen atoms. Ra' 1 Or Ra' 2When is an alkyl group, the alkyl group may be the same as the alkyl group exemplified as the substituent that may be bonded to the carbon atom at the α-position in the explanation of the α-substituted acrylic acid ester above, and an alkyl group having 1 to 5 carbon atoms is preferable. Specifically, a linear or branched alkyl group is preferable. More specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and the like are preferable, and a methyl group or an ethyl group is more preferable, and a methyl group is particularly preferable.

[0037] In formula (a1-r-1), Ra' 3 Examples of the hydrocarbon group include a linear or branched alkyl group, and a cyclic hydrocarbon group. The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

[0038] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably has 3 to 5 carbon atoms. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, and is preferably an isopropyl group.

[0039] Ra' 3 When is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0040] Ra' 3 When the cyclic hydrocarbon group is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is replaced with a heteroatom. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Ra' 3 Specific examples of the aromatic hydrocarbon group in the above include a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); a group in which one hydrogen atom has been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocycle has been substituted with an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The number of carbon atoms of the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0041] Ra' 3The cyclic hydrocarbon group in may have a substituent. Examples of the substituent include those described above for Ra x5 The same can be mentioned.

[0042] Ra' 3 But Ra' 1 , Ra' 2 When it is bonded to any one of the above to form a ring, the cyclic group is preferably a 4- to 7-membered ring, more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group, a tetrahydrofuranyl group, etc.

[0043] Tertiary alkyl ester type acid-labile group: Among the above polar groups, examples of the acid-dissociable group that protects the carboxy group include acid-dissociable groups represented by the following general formula (a1-r-2). Among the acid-dissociable groups represented by the following formula (a1-r-2), those constituted by an alkyl group may be referred to as "tertiary alkyl ester-type acid-dissociable groups" hereinafter for the sake of convenience.

[0044] [ka] [In the formula, Ra' 4 ~Ra' 6 are each a hydrocarbon group, and Ra' 5 , Ra' 6 may be bonded to each other to form a ring.

[0045] Ra' 4 Examples of the hydrocarbon group include a linear or branched alkyl group, a linear or cyclic alkenyl group, or a cyclic hydrocarbon group. Ra' 4 The linear or branched alkyl group and the cyclic hydrocarbon group (the monocyclic aliphatic hydrocarbon group, the polycyclic aliphatic hydrocarbon group, and the aromatic hydrocarbon group) in 3 The same can be mentioned. Ra' 4 The chain or cyclic alkenyl group in is preferably an alkenyl group having 2 to 10 carbon atoms. Ra' 5 , Ra' 6 As the hydrocarbon group of Ra' 3 The same can be mentioned.

[0046] Ra' 5 and Ra' 6 and (a1-r2-3) are preferably used. On the other hand, Ra' 4 ~Ra' 6 When are not bonded to each other and are independent hydrocarbon groups, preferred examples include groups represented by the following general formula (a1-r2-4).

[0047] [ka] [In formula (a1-r2-1), Ra' 10 Ra' represents a linear or branched alkyl group having 1 to 12 carbon atoms, some of which may be substituted with a halogen atom or a heteroatom-containing group. 11 Is Ra' 10 In formula (a1-r2-2), Ya is a carbon atom. Xa is a group that forms a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms in this cyclic hydrocarbon group may be substituted. Ra 101 ~Ra 103 are each independently a hydrogen atom, a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent cyclic aliphatic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms in the linear saturated hydrocarbon group and the cyclic aliphatic saturated hydrocarbon group may be substituted. 101 ~Ra 103 Two or more of may be bonded to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group which forms an aliphatic cyclic group together with Yaa. Ra 104 In formula (a1-r2-4), Ra' is an aromatic hydrocarbon group which may have a substituent.12 and Ra' 13 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. Some or all of the hydrogen atoms in this chain saturated hydrocarbon group may be substituted. 14 is a hydrocarbon group which may have a substituent. * indicates a bond.]

[0048] In the above formula (a1-r2-1), Ra' 10 represents a linear or branched alkyl group having 1 to 12 carbon atoms which may be partially substituted with a halogen atom or a heteroatom-containing group.

[0049] Ra' 10 In the formula, the linear alkyl group has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms. Ra' 10 As the branched alkyl group in the formula (I), 3 The same can be mentioned.

[0050] Ra' 10 The alkyl group in may be partially substituted with a halogen atom or a heteroatom-containing group. For example, some of the hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a heteroatom-containing group. In addition, some of the carbon atoms (e.g., methylene groups) constituting the alkyl group may be substituted with a heteroatom-containing group. The heteroatom includes an oxygen atom, a sulfur atom, and a nitrogen atom. The heteroatom-containing group includes (-O-), -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -S-, -S(=O) 2 -, -S(=O) 2 -O- and the like.

[0051] In formula (a1-r2-1), Ra' 11 (Ra' 10 The aliphatic cyclic group formed together with the carbon atom to which is bonded) is Ra' in formula (a1-r-1).3 Among them, a monocyclic alicyclic hydrocarbon group is preferred, and specifically, a cyclopentyl group or a cyclohexyl group is more preferred, and a cyclopentyl group is even more preferred.

[0052] In the formula (a1-r2-2), the cyclic hydrocarbon group formed by Xa together with Ya includes Ra' in the formula (a1-r-1). 3 Examples of such groups include groups in which one or more hydrogen atoms have been further removed from the cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) in the above formula. The cyclic hydrocarbon group formed by Xa together with Ya may have a substituent. Examples of the substituent include the above-mentioned Ra' 3 Examples of the substituents include those similar to those that the cyclic hydrocarbon group in the above may have. In formula (a1-r2-2), Ra 101 ~Ra 103 In the above formula, examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a decyl group. Ra 101 ~Ra 103 In the above formula, examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, and a cyclododecyl group; and polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.02,6]decanyl group, a tricyclo[3.3.1.13,7]decanyl group, a tetracyclo[6.2.1.13,6.02,7]dodecanyl group, and an adamantyl group. Ra 101 ~Ra 103 Among these, from the viewpoint of ease of synthesis, a hydrogen atom or a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms is preferable, and among these, a hydrogen atom, a methyl group, or an ethyl group is more preferable, and a hydrogen atom is particularly preferable.

[0053] The above Ra 101 ~Ra 103 Examples of the substituents of the chain saturated hydrocarbon group or the cyclic saturated aliphatic hydrocarbon group represented by the formula x5 The same groups as those shown below can be mentioned.

[0054] Ra 101 ~Ra 103 Examples of groups containing a carbon-carbon double bond formed by two or more of the above being bonded to each other to form a cyclic structure include a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, a methylcyclohexenyl group, a cyclopentylidene-ethenyl group, a cyclohexylidene-ethenyl group, etc. Among these, from the viewpoint of ease of synthesis, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylidene-ethenyl group are preferred.

[0055] In formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is represented by Ra' in formula (a1-r-1). 3 The groups mentioned above as the aliphatic hydrocarbon group are preferably monocyclic or polycyclic groups. In formula (a1-r2-3), Ra 104 Examples of the aromatic hydrocarbon group in the formula include a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. 104 is preferably a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene, or phenanthrene, still more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, or anthracene, particularly preferably a group in which one or more hydrogen atoms have been removed from benzene or naphthalene, and most preferably a group in which one or more hydrogen atoms have been removed from benzene.

[0056] Ra in formula (a1-r2-3) 104Examples of the substituent that may be possessed by the group include a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom, an alkoxy group (such as a methoxy group, an ethoxy group, a propoxy group, or a butoxy group), and an alkyloxycarbonyl group.

[0057] In formula (a1-r2-4), Ra' 12 and Ra' 13 Each of Ra' independently represents a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. 12 and Ra' 13 In the above, the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms is 101 ~Ra 103 Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in the above formula (1) include those in which some or all of the hydrogen atoms in the chain saturated hydrocarbon group may be substituted. Ra' 12 and Ra' 13 Among these, a hydrogen atom or an alkyl group having 1 to 5 carbon atoms is preferable, an alkyl group having 1 to 5 carbon atoms is more preferable, a methyl group or an ethyl group is further preferable, and a methyl group is particularly preferable. The above Ra' 12 and Ra' 13 In the case where the chain saturated hydrocarbon group represented by the formula (I) is substituted, examples of the substituent include the above-mentioned Ra x5 The same groups as those shown below can be mentioned.

[0058] In formula (a1-r2-4), Ra' 14 Ra' is a hydrocarbon group which may have a substituent. 14 The hydrocarbon group in the formula (I) includes a linear or branched alkyl group, or a cyclic hydrocarbon group.

[0059] Ra' 14The linear alkyl group in the formula (I) preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

[0060] Ra' 14 The branched alkyl group in the above formula (I) preferably has 3 to 10 carbon atoms, and more preferably has 3 to 5 carbon atoms. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, and is preferably an isopropyl group.

[0061] Ra' 14 When is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0062] Ra' 14 As the aromatic hydrocarbon group in 104 Among them, the aromatic hydrocarbon group Ra' is the same as that in 14is preferably a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene, or phenanthrene, still more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, or anthracene, particularly preferably a group in which one or more hydrogen atoms have been removed from naphthalene or anthracene, and most preferably a group in which one or more hydrogen atoms have been removed from naphthalene. Ra' 14 Examples of the substituent that may be possessed by Ra include 104 The substituents may be the same as those which may be possessed by the group.

[0063] Ra' in formula (a1-r2-4) 14 When is a naphthyl group, the position at which it is bonded to the tertiary carbon atom in the above formula (a1-r2-4) may be either the 1st or 2nd position of the naphthyl group. Ra' in formula (a1-r2-4) 14 When is an anthryl group, the position at which it is bonded to the tertiary carbon atom in the above formula (a1-r2-4) may be any one of the 1-position, 2-position, or 9-position of the anthryl group.

[0064] Specific examples of the group represented by formula (a1-r2-1) are shown below.

[0065] [ka]

[0066] [ka]

[0067] [ka]

[0068] Specific examples of the group represented by formula (a1-r2-2) are shown below.

[0069] [ka]

[0070] [ka]

[0071] [ka]

[0072] Specific examples of the group represented by formula (a1-r2-3) are shown below.

[0073] [ka]

[0074] Specific examples of the group represented by formula (a1-r2-4) are shown below.

[0075] [ka]

[0076] Tertiary alkyloxycarbonyl acid dissociating group: Among the polar groups, examples of the acid dissociable group that protects the hydroxyl group include acid dissociable groups represented by the following general formula (a1-r-3) (hereinafter, for convenience, may be referred to as "tertiary alkyloxycarbonyl acid dissociable group").

[0077] [ka] [In the formula, Ra' 7 ~Ra' 9 are each an alkyl group.

[0078] In formula (a1-r-3), Ra' 7 ~Ra' 9Each of the groups is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. The total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0079] Examples of the structural unit (a1) include a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, a structural unit derived from an acrylamide, a structural unit derived from hydroxystyrene or a hydroxystyrene derivative in which at least a portion of the hydrogen atoms in the hydroxyl groups are protected with a substituent containing the above-mentioned acid-decomposable group, and a structural unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative in which at least a portion of the hydrogen atoms in -C(═O)-OH are protected with a substituent containing the above-mentioned acid-decomposable group.

[0080] Of the above, the structural unit (a1) is preferably a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. Preferred specific examples of the structural unit (a1) include structural units represented by the following general formula (a1-1) or (a1-2).

[0081] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. 1 is a divalent hydrocarbon group which may have an ether bond. a1 is an integer from 0 to 2. 1 is an acid-dissociable group represented by the above general formula (a1-r-1) or (a1-r-2). 1 is a2 +1-valent hydrocarbon group, n a2 is an integer from 1 to 3, and Ra 2is an acid-dissociable group represented by the above general formula (a1-r-1) or (a1-r-3).

[0082] In the formula (a1-1), the alkyl group of R having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is most preferable.

[0083] In the formula (a1-1), Va 1 The divalent hydrocarbon group in may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0084] Va 1 The aliphatic hydrocarbon group as the divalent hydrocarbon group in the formula (I) may be saturated or unsaturated, and is usually preferably saturated. More specifically, the aliphatic hydrocarbon group may be a straight-chain or branched-chain aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure.

[0085] The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, specifically, a methylene group [-CH 2 -], ethylene group [-(CH 2 ) 2 -], trimethylene group [-(CH 2 ) 3-], tetramethylene group [-(CH 2 ) 4 -], pentamethylene group [-(CH 2 ) 5 -] etc. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably has 3 to 6 carbon atoms, even more preferably has 3 or 4 carbon atoms, and most preferably has 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, specifically, -CH(CH 3 )-, -CH(CH 2 CH 3 )-, -C(CH 3 ) 2 -, -C(CH 3 )(CH 2 CH 3 )-, -C(CH 3 )(CH 2 CH 2 CH 3 )-, -C(CH 2 CH 3 ) 2 -, etc. alkylmethylene groups; -CH(CH 3 )CH 2 -, -CH(CH 3 )CH(CH 3 )-, -C(CH 3 ) 2 CH 2 -, -CH(CH 2 CH 3 )CH 2 -, -C(CH 2 CH 3 ) 2 -CH 2 -, etc. alkyl ethylene groups; -CH(CH 3 )CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 -, etc.; -CH(CH 3 )CH 2 CH 2 CH 2 -, -CH 2 CH(CH 3 )CH2 CH 2 The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0086] Examples of the aliphatic hydrocarbon group containing a ring in the structure include an alicyclic hydrocarbon group (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, etc. Examples of the linear or branched aliphatic hydrocarbon group include the same as the linear aliphatic hydrocarbon group or the branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, specifically cycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.

[0087] Va 1 The aromatic hydrocarbon group as the divalent hydrocarbon group in the formula (I) is a hydrocarbon group having an aromatic ring. Such an aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in the substituents. Specific examples of the aromatic ring contained in the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a heteroatom, etc. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring (arylene group); a group in which one hydrogen atom of a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring (aryl group) has been substituted with an alkylene group (for example, a group in which one hydrogen atom has been further removed from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group). The number of carbon atoms in the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0088] In the formula (a1-1), Ra 1 is an acid-dissociable group represented by the above formula (a1-r-1) or (a1-r-2).

[0089] In the formula (a1-2), Wa 1 n in a2 The +1-valent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity, and may be saturated or unsaturated, and is usually preferably saturated. The aliphatic hydrocarbon group may be a straight-chain or branched-chain aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, or a group that combines a straight-chain or branched-chain aliphatic hydrocarbon group with an aliphatic hydrocarbon group containing a ring in its structure. The above n a2 The +1 valency is preferably 2 to 4, more preferably 2 or 3.

[0090] In the formula (a1-2), Ra 2is an acid-dissociable group represented by the above general formula (a1-r-1) or (a1-r-3).

[0091] Specific examples of the structural unit represented by the formula (a1-1) are shown below. In each of the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0092] [ka]

[0093] [ka]

[0094] [ka]

[0095] [ka]

[0096] [ka]

[0097] [ka]

[0098] [ka]

[0099] [ka]

[0100] The structural unit (a1) contained in the component (A1) may be of one type, or two or more types. As the structural unit (a1), a structural unit represented by the above formula (a1-1) is more preferable, since it is easier to improve the characteristics (sensitivity, shape, etc.) in electron beam or EUV lithography. Among these, as the structural unit (a1), those containing a structural unit represented by general formula (a1-1-1) shown below are particularly preferable.

[0101] [ka] [In the formula, Ra 1 " is an acid-dissociable group represented by general formula (a1-r2-1), (a1-r2-3) or (a1-r2-4).

[0102] In the formula (a1-1-1), R and Va 1 and n a1 R and Va in the formula (a1-1) 1 and n a1 is the same as: The acid dissociable group represented by formula (a1-r2-1), (a1-r2-3) or (a1-r2-4) is as described above. Among them, it is preferable to select the acid dissociable group as a cyclic group, since it is suitable for EB or EUV use in that the reactivity can be increased.

[0103] In the formula (a1-1-1), Ra 1 " is preferably an acid dissociable group represented by general formula (a1-r2-1) or general formula (a1-r2-3) among the above, and more preferably an acid dissociable group represented by general formula (a1-r2-1).

[0104] The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mol %, more preferably 10 to 75 mol %, even more preferably 10 to 70 mol %, and particularly preferably 10 to 60 mol %, based on the total (100 mol %) of all structural units constituting the component (A1). By ensuring that the proportion of the structural unit (a1) is at least as large as the lower limit of the aforementioned preferred range, lithography properties such as sensitivity, resolution, and roughness can be improved. On the other hand, by ensuring that the proportion is at most the upper limit of the aforementioned preferred range, a balance with other structural units can be achieved, resulting in various favorable lithography properties.

[0105] Other structural units The component (A1) may contain other structural units, in addition to the structural unit (a1) described above, as necessary. Examples of other structural units include the structural unit (a10) represented by general formula (a10-1) described later; 2 Examples of such structural units include (a2) a structural unit containing a --containing cyclic group or a carbonate-containing cyclic group; (a3) ​​a structural unit containing a polar group-containing aliphatic hydrocarbon group; (a4) a structural unit containing an acid non-dissociable aliphatic cyclic group; and (st) a structural unit derived from styrene or a styrene derivative.

[0106] Regarding the structural unit (a10): The structural unit (a10) is a structural unit represented by general formula (a10-1) shown below.

[0107] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. x1 is a single bond or a divalent linking group. x1 is an aromatic hydrocarbon group which may have a substituent. ax1 is an integer greater than or equal to 1.

[0108] In the above formula (a10-1), R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. The alkyl group having 1 to 5 carbon atoms for R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms for R is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, more preferably a hydrogen atom, a methyl group, or a trifluoromethyl group, still more preferably a hydrogen atom or a methyl group, and particularly preferably a methyl group.

[0109] In the formula (a10-1), Ya x1 is a single bond or a divalent linking group. In the above chemical formula, Ya x1 The divalent linking group in is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom.

[0110] Optionally substituted divalent hydrocarbon group: Ya x1 When is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0111] Ya x1 Aliphatic hydrocarbon groups in The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, and aliphatic hydrocarbon groups containing a ring in the structure.

[0112] Linear or branched aliphatic hydrocarbon groups The linear aliphatic hydrocarbon group preferably contains 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, specifically, a methylene group [-CH 2 -], ethylene group [-(CH 2 ) 2 -], trimethylene group [-(CH 2 ) 3 -], tetramethylene group [-(CH 2 ) 4 -], pentamethylene group [-(CH 2 ) 5 -] etc. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably has 3 to 6 carbon atoms, even more preferably has 3 or 4 carbon atoms, and most preferably has 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, specifically, -CH(CH 3 )-, -CH(CH 2 CH 3 )-, -C(CH 3 ) 2 -, -C(CH 3 )(CH 2 CH 3 )-, -C(CH 3 )(CH 2 CH 2 CH 3 )-, -C(CH 2 CH 3 ) 2 -, etc. alkylmethylene groups; -CH(CH 3 )CH 2 -, -CH(CH 3 )CH(CH 3 )-, -C(CH 3 ) 2 CH 2 -, -CH(CH 2 CH 3 )CH 2 -, -C(CH 2 CH3 ) 2 -CH 2 -, etc. alkyl ethylene groups; -CH(CH 3 )CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 -, etc.; -CH(CH 3 )CH 2 CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 CH 2 The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0113] The linear or branched aliphatic hydrocarbon group may or may not have a substituent, which may include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms and substituted with a fluorine atom, and a carbonyl group.

[0114] Aliphatic hydrocarbon groups containing rings in the structure Examples of the aliphatic hydrocarbon group containing a ring in the structure include a cyclic aliphatic hydrocarbon group (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring) which may contain a substituent containing a heteroatom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, specifically cycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.

[0115] The cyclic aliphatic hydrocarbon group may or may not have a substituent, such as an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, or a carbonyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and further preferably a methoxy group or an ethoxy group. The halogen atom as the substituent is preferably a fluorine atom. Examples of the halogenated alkyl group as the substituent include the alkyl groups in which some or all of the hydrogen atoms of the alkyl groups are substituted with the halogen atoms. In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. Examples of the substituent containing a hetero atom include -O-, -C(=O)-O-, -S-, -S(=O) 2 -, -S(=O) 2 -O- is preferred.

[0116] Ya x1 Aromatic hydrocarbon groups in The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is replaced with a heteroatom. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); a group in which two hydrogen atoms have been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); a group in which one hydrogen atom of a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) has been substituted with an alkylene group (e.g., a group in which one hydrogen atom has been further removed from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group). The number of carbon atoms of the alkylene group bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1 carbon atom.

[0117] The aromatic hydrocarbon group may have a hydrogen atom substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Examples of the alkoxy group, halogen atom and halogenated alkyl group as the substituent include those exemplified as the substituent substituting a hydrogen atom of the cyclic aliphatic hydrocarbon group.

[0118] Divalent linking groups containing heteroatoms: Ya x1 When is a divalent linking group containing a hetero atom, preferred examples of the linking group include -O-, -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with a substituent such as an alkyl group or an acyl group), -S-, -S(=O) 2 -, -S(=O) 2 -O-, general formula -Y 21 -OY 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-OY 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -OC(=O)-Y 22 -or-Y 21 -S(=O) 2 -OY 22 -, wherein Y 21 and Y 22 each independently represents a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m″ is an integer of 0 to 3. When the divalent linking group containing a hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, or -NH-C(=NH)-, the H may be substituted with a substituent such as an alkyl group, acyl, etc. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5 carbon atoms. General formula-Y 21 -OY 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-OY 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -OC(=O)-Y 22 -or-Y 21 -S(=O) 2 -OY 22 -Medium, Y 21 and Y 22 Each of Ya is independently a divalent hydrocarbon group which may have a substituent. x1 Examples of the divalent linking group in the above formula (divalent hydrocarbon group which may have a substituent) include those mentioned above. Y 21 As the alkyl group, a straight-chain aliphatic hydrocarbon group is preferable, a straight-chain alkylene group is more preferable, a straight-chain alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group or ethylene group is particularly preferable. Y 22 is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group. Formula − [Y 21 -C(=O)-O] m” -Y 22 In the group represented by -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 1. That is, the group represented by the formula -[Y 21 -C(=O)-O] m” -Y 22 The group represented by the formula -Y 21 -C(=O)-OY 22 Particularly preferred is a group represented by the formula -(CH 2 ) a’-C(=O)-O-(CH 2 ) b’ In the formula, a' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1. b' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1.

[0119] Among the above, Ya x1 is preferably a single bond, an ester bond [-C(=O)-O-, -OC(=O)-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof, and more preferably a single bond or an ester bond [-C(=O)-O-, -OC(=O)-].

[0120] In the formula (a10-1), Wa x1 is an aromatic hydrocarbon group which may have a substituent. Wa x1 The aromatic hydrocarbon group in the formula (n) is an aromatic ring which may have a substituent. ax1 4n+1) hydrogen atoms are removed. The aromatic ring here is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a heteroatom. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Also, Wa x1 The aromatic hydrocarbon group in the formula (n) may be an aromatic compound having an aromatic ring which may have two or more substituents (e.g., biphenyl, fluorene, etc.). ax1 +1) hydrogen atoms may also be removed. Among these, Wa x1 is preferably a group obtained by removing (n ax1 +1) hydrogen atoms from benzene, naphthalene, anthracene or biphenyl, more preferably a group obtained by removing (n ax1 +1) hydrogen atoms from benzene or naphthalene, and even more preferably a group obtained by removing (n ax1 +1) hydrogen atoms from benzene.

[0121] The aromatic hydrocarbon group in Wa x1 may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, etc. The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent are the same as those listed as the substituent of the cyclic aliphatic hydrocarbon group in Ya x1 . The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, even more preferably an ethyl group or a methyl group, and particularly preferably a methyl group. The aromatic hydrocarbon group in Wa x1 preferably has no substituent.

[0122] In the formula (a10-1), n ax1 is an integer of 1 or more, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, even more preferably 1, 2 or 3, and particularly preferably 1 or 2.

[0123] Specific examples of the structural unit (a10) represented by the formula (a10-1) are shown below. In the following formulas, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[0124]

Chemical formula

[0125]

Chemical formula

[0126] [ka]

[0127] [ka]

[0128] The structural unit (a10) contained in the component (A1) may be of one type, or two or more types. When the component (A1) contains the structural unit (a10), the proportion of the structural unit (a10) in the component (A1) is preferably 5 to 80 mol %, more preferably 10 to 75 mol %, even more preferably 30 to 70 mol %, and particularly preferably 30 to 60 mol %, based on the total (100 mol %) of all structural units constituting the component (A1). By ensuring that the proportion of the structural unit (a10) is at least as large as the lower limit of the above range, it is possible to further increase the sensitivity, whereas by ensuring that the proportion is at most the upper limit of the above range, it is easier to achieve a balance with other structural units.

[0129] Regarding the structural unit (a2): The component (A1) is a lactone-containing cyclic group, -SO 2 It may also have a structural unit (a2) containing a --containing cyclic group or a carbonate-containing cyclic group (provided that this does not include those corresponding to the aforementioned structural unit (a01) or the aforementioned structural unit (a1)). The lactone-containing cyclic group of the structural unit (a2), -SO 2 The --containing cyclic group or carbonate-containing cyclic group is effective in improving the adhesion of the resist film to the substrate when the component (A1) is used to form a resist film. Furthermore, the inclusion of the structural unit (a2) provides effects such as appropriate adjustment of the acid diffusion length, improved adhesion of the resist film to the substrate, and appropriate adjustment of the solubility during development, resulting in improved lithography properties.

[0130] A "lactone-containing cyclic group" refers to a cyclic group that contains a ring (lactone ring) containing -OC(=O)- in its ring skeleton. The lactone ring is counted as the first ring, and when there is only a lactone ring, it is called a monocyclic group, and when there is further a ring structure, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group. The lactone-containing cyclic group in the structural unit (a2) is not particularly limited and any suitable group can be used. Specific examples include the groups represented by the following general formulae (a2-r-1) to (a2-r-7).

[0131] [ka] [In the formula, Ra' 21 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO 2 -containing cyclic group; A″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom (—O—) or a sulfur atom (—S—), an oxygen atom, or a sulfur atom, n′ is an integer of 0 to 2, and m′ is 0 or 1.

[0132] In the general formulas (a2-r-1) to (a2-r-7), Ra' 21 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and a hexyl group. Among these, a methyl group or an ethyl group is preferred, and a methyl group is particularly preferred. Ra' 21 The alkoxy group in the formula (1) is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the alkoxy group in the formula (1) is preferably an alkoxy group having 1 to 6 carbon atoms.21 Examples of the alkyl group include those groups in which the alkyl groups mentioned above are linked to an oxygen atom (-O-). Ra' 21 As the halogen atom in, a fluorine atom is preferable. Ra' 21 As the halogenated alkyl group in the above, Ra' 21 and groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with the above halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferred, and a perfluoroalkyl group is particularly preferred.

[0133] Ra' 21 In -COOR" and -OC(=O)R", R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO 2 -containing cyclic group. The alkyl group in R'' may be linear, branched, or cyclic, and preferably has 1 to 15 carbon atoms. When R″ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably has 1 to 5 carbon atoms, and is particularly preferably a methyl group or an ethyl group. When R" is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specific examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as a bicycloalkane, a tricycloalkane, or a tetracycloalkane. More specific examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; and groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples of the lactone-containing cyclic group in R″ include the same groups as those represented by the general formulae (a2-r-1) to (a2-r-7) above. The carbonate-containing cyclic group in R″ is the same as the carbonate-containing cyclic group described later, and specific examples thereof include groups represented by general formulae (ax3-r-1) to (ax3-r-3). -SO in R” 2 Examples of the --containing cyclic group include the -SO 2 Similar to the -containing cyclic group, specific examples include the groups represented by general formulae (a5-r-1) to (a5-r-4). Ra' 21 The hydroxyalkyl group in Ra' is preferably one having 1 to 6 carbon atoms. 21 In the above formula, at least one hydrogen atom of the alkyl group is substituted with a hydroxyl group. Ra' 21 At least one of the groups is preferably a cyano group.

[0134] In the general formulae (a2-r-2), (a2-r-3) and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A" is preferably a linear or branched alkylene group, and examples thereof include a methylene group, an ethylene group, an n-propylene group and an isopropylene group. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include groups in which -O- or -S- is present at the terminal or between the carbon atoms of the alkylene group, and examples thereof include O-CH 2 -, -CH 2 -O-CH 2 -,-S-CH 2 -, -CH 2 -S-CH 2 A″ is preferably an alkylene group having 1 to 5 carbon atoms or —O—, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

[0135] Specific examples of the groups represented by general formulas (a2-r-1) to (a2-r-7) are listed below.

[0136] [ka]

[0137] [ka]

[0138] "-SO 2 "-containing cyclic group" means a group having a -SO 2 A cyclic group containing a ring containing -, specifically, -SO 2 The sulfur atom (S) in - forms part of the ring structure of the cyclic group. 2 The ring containing - is counted as the first ring, and if there is only this ring, it is called a monocyclic group, and if there are other ring structures, it is called a polycyclic group regardless of the structure. 2 The -containing cyclic group may be a monocyclic group or a polycyclic group. -SO 2 The -containing cyclic group in particular has an -O-SO 2 Cyclic groups containing -, i.e. -O-SO 2 It is preferred that -OS- in - is a cyclic group containing a sultone ring forming part of the ring backbone. -SO 2 More specific examples of the --containing cyclic group include groups represented by the following general formulas (a5-r-1) to (a5-r-4).

[0139] [ka] [In the formula, Ra' 51 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO 2-containing cyclic group; A″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom, and n′ is an integer of 0 to 2.

[0140] In the general formulae (a5-r-1) and (a5-r-2), A" is the same as A" in the general formulae (a2-r-2), (a2-r-3) and (a2-r-5). Ra' 51 The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in the general formulae (a2-r-1) to (a2-r-7) are each represented by Ra' 21 Examples of the above-mentioned are similar to those mentioned in the explanation of the above. Specific examples of the groups represented by general formulas (a5-r-1) to (a5-r-4) are shown below, in which "Ac" represents an acetyl group.

[0141] [ka]

[0142] [ka]

[0143] [ka]

[0144] The term "carbonate-containing cyclic group" refers to a cyclic group that contains a ring (carbonate ring) containing -OC(=O)-O- in its ring skeleton. The carbonate ring is counted as the first ring, and when there is only a carbonate ring, it is called a monocyclic group, and when there is another ring structure, it is called a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group. The carbonate ring-containing cyclic group is not particularly limited and any one can be used. Specific examples include groups represented by the following general formulae (ax3-r-1) to (ax3-r-3).

[0145] [ka] [In the formula, Ra' x31 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO 2 -containing cyclic group; A″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom; p′ is an integer of 0 to 3, and q′ is 0 or 1.

[0146] In the general formulae (ax3-r-2) to (ax3-r-3), A" is the same as A" in the general formulae (a2-r-2), (a2-r-3) and (a2-r-5). Ra' 31 The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in the general formulae (a2-r-1) to (a2-r-7) are each represented by Ra' 21 Examples of the above-mentioned are similar to those mentioned in the explanation of the above. Specific examples of the groups represented by the general formulae (ax3-r-1) to (ax3-r-3) are listed below.

[0147] [ka]

[0148] Of the various possibilities, the structural unit (a2) is preferably a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

[0149] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. 21 is a single bond or a divalent linking group. 21 is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, where R' represents a hydrogen atom or a methyl group. 21 If -O-, Ya 21 does not become -CO-. Ra 21 is a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO 2 -containing cyclic group.

[0150] In the formula (a2-1), R is the same as defined above. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is particularly preferable.

[0151] In the formula (a2-1), Ya 21 As the divalent linking group, Ya in the above general formula (a10-1) is x1 The divalent linking group may be the same as the divalent linking group in the above formula.

[0152] Among the above, Ya 21 is preferably a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0153] In the above formula (a2-1), Ra 21 is a lactone-containing cyclic group, -SO 2 -containing cyclic group or a carbonate-containing cyclic group. Ra 21 The lactone-containing cyclic group, -SO2 - The cyclic group and the carbonate-containing cyclic group preferably include the groups represented by the general formulas (a2-r-1) to (a2-r-7), the groups represented by the general formulas (a5-r-1) to (a5-r-4), and the groups represented by the general formulas (ax3-r-1) to (ax3-r-3), respectively. Among them, a lactone-containing cyclic group or a -SO 2 - containing cyclic group is preferable, and the groups represented by the general formulas (a2-r-1), (a2-r-2), (a2-r-6), or (a5-r-1) are more preferable. Specifically, any of the groups represented by the chemical formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-18), (r-lc-6-1), (r-sl-1-1), and (r-sl-1-18) is more preferable, the group represented by the chemical formula (r-lc-2-1) or (r-lc-2-12) is further preferable, and the group represented by the chemical formula (r-lc-2-12) is particularly preferable.

[0154] The structural unit (a2) contained in the component (A1) may be one kind or two or more kinds. When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 5 to 95 mol%, more preferably 10 to 90 mol%, further preferably 20 to 90 mol%, and particularly preferably 30 to 90 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). When the proportion of the structural unit (a2) is equal to or higher than the preferable lower limit value, the effect of containing the structural unit (a2) can be sufficiently obtained due to the above-described effect, and when it is equal to or lower than the upper limit value, a balance with other structural units can be achieved, and various lithography characteristics become good.

[0155] Regarding the structural unit (a3): The component (A1) may further include a structural unit (a3) ​​(excluding those corresponding to the structural unit (a01), the structural unit (a1), the structural unit (a2), or the structural unit (a8)) that contains a polar group-containing aliphatic hydrocarbon group. When the component (A1) includes the structural unit (a3), the hydrophilicity of the component (A1) is enhanced, which contributes to improving the resolution. In addition, the acid diffusion length can be appropriately adjusted.

[0156] Examples of the polar group include a hydroxyl group, a cyano group, and a carboxyl group, with a hydroxyl group being particularly preferred. Examples of the aliphatic hydrocarbon group include linear or branched hydrocarbon groups having 1 to 10 carbon atoms (preferably alkylene groups) and cyclic aliphatic hydrocarbon groups (cyclic groups). The cyclic group may be a monocyclic group or a polycyclic group, and can be appropriately selected from the many groups proposed for use in resins for resist compositions for ArF excimer lasers.

[0157] When the cyclic group is a monocyclic group, the number of carbon atoms is more preferably 3 to 10. Among them, a structural unit derived from an acrylic ester containing an aliphatic monocyclic group containing a hydroxyl group, a cyano group, or a carboxy group is more preferable. An example of the monocyclic group is a group in which two or more hydrogen atoms have been removed from a monocycloalkane. Specifically, it can be exemplified by a group in which two or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane, cyclohexane, or cyclooctane. Among these monocyclic groups, a group in which two or more hydrogen atoms have been removed from cyclopentane and a group in which two or more hydrogen atoms have been removed from cyclohexane are industrially preferable.

[0158] When the cyclic group is a polycyclic group, the number of carbon atoms of the polycyclic group is more preferably 7 to 30. Among them, a structural unit derived from an acrylic ester containing an aliphatic polycyclic group containing a hydroxyl group, a cyano group, or a carboxy group is more preferable. Examples of the polycyclic group include groups obtained by removing two or more hydrogen atoms from bicycloalkanes, tricycloalkanes, tetracycloalkanes, etc. Specific examples include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, groups obtained by removing two or more hydrogen atoms from adamantane, groups obtained by removing two or more hydrogen atoms from norbornane, and groups obtained by removing two or more hydrogen atoms from tetracyclododecane are industrially preferable.

[0159] There are no particular limitations on the structural unit (a3), and any structural unit can be used as long as it contains a polar group-containing aliphatic hydrocarbon group. The structural unit (a3) ​​is preferably a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and which contains a polar group-containing aliphatic hydrocarbon group. As the structural unit (a3), when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a straight-chain or branched-chain hydrocarbon group having 1 to 10 carbon atoms, a structural unit derived from a hydroxyethyl ester of acrylic acid is preferred. Furthermore, examples of the structural unit (a3) ​​that can be mentioned as being preferable are structural units represented by the following formula (a3-1) and structural units represented by the following formula (a3-2).

[0160] [ka] [In the formula, R is the same as defined above, j is an integer of 1 to 3, and k is an integer of 1 to 3.]

[0161] In formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3rd position of the adamantyl group. It is preferable that j is 1, and it is particularly preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.

[0162] In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5- or 6-position of the norbornyl group.

[0163] The structural unit (a3) ​​contained in the component (A1) may be of one type, or two or more types. When the component (A1) contains the structural unit (a3), the proportion of the structural unit (a3) ​​relative to the total (100 mol %) of all structural units constituting the component (A1) is preferably 1 to 30 mol %, more preferably 2 to 25 mol %, and even more preferably 5 to 20 mol %. By ensuring that the proportion of the structural unit (a3) ​​is at least as large as the preferred lower limit, the effects described above can be fully achieved by including the structural unit (a3). By ensuring that the proportion of the structural unit (a3) ​​is at most the preferred upper limit, a balance with other structural units can be achieved, and various lithography properties become favorable.

[0164] Regarding the structural unit (a4): The component (A1) may further include a structural unit (a4) that contains an acid non-dissociable aliphatic cyclic group. By including the structural unit (a4) in the component (A1), the dry etching resistance of the formed resist pattern is improved. In addition, the hydrophobicity of the component (A1) is enhanced. The improved hydrophobicity contributes to improvements in the resolution, resist pattern shape, etc., particularly in the case of a solvent development process. The “acid non-dissociable cyclic group” within the structural unit (a4) is a cyclic group that, when acid is generated in the resist composition upon exposure (for example, when acid is generated from a structural unit that generates acid upon exposure or from the component (B)), does not dissociate even when acted upon by the acid, and remains as is within the structural unit.

[0165] The structural unit (a4) is preferably, for example, a structural unit derived from an acrylate ester containing an acid non-dissociable aliphatic cyclic group. The cyclic group can be any of a large number of conventionally known resin components for resist compositions for ArF excimer lasers, KrF excimer lasers (preferably ArF excimer lasers), etc. The cyclic group is preferably at least one selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group, in terms of industrial availability, etc. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent. Specific examples of the structural unit (a4) include the structural units represented by the following general formulas (a4-1) to (a4-7).

[0166] [ka] [In the formula, R α is the same as above.]

[0167] The structural unit (a4) contained in the component (A1) may be of one type, or two or more types. When the component (A1) contains the structural unit (a4), the proportion of the structural unit (a4) is preferably 1 to 40 mol %, and more preferably 1 to 20 mol %, based on the total (100 mol %) of all structural units constituting the component (A1). By ensuring that the proportion of the structural unit (a4) is at least as large as the preferred lower limit, the effects of including the structural unit (a4) can be fully obtained, while by ensuring that the proportion is no more than the preferred upper limit, it becomes easier to achieve a balance with other structural units.

[0168] Regarding the structural unit (st): The structural unit (st) is a structural unit derived from styrene or a styrene derivative. A "structural unit derived from styrene" refers to a structural unit formed by cleavage of the ethylenic double bond of styrene. A "structural unit derived from a styrene derivative" refers to a structural unit formed by cleavage of the ethylenic double bond of a styrene derivative (however, this does not include those that fall under the structural unit (a10)).

[0169] The term "styrene derivative" refers to a compound in which at least some of the hydrogen atoms of styrene are substituted with a substituent. Examples of styrene derivatives include those in which the hydrogen atom at the α-position of styrene is substituted with a substituent, those in which one or more hydrogen atoms on the benzene ring of styrene are substituted with a substituent, and those in which the hydrogen atom at the α-position of styrene and one or more hydrogen atoms on the benzene ring are substituted with a substituent.

[0170] Examples of the substituent that substitutes the hydrogen atom at the α-position of styrene include an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms. The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable. The substituent substituting the hydrogen atom at the α-position of styrene is preferably an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or a fluorinated alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group from the viewpoint of industrial availability.

[0171] Examples of the substituent that substitutes the hydrogen atom on the benzene ring of styrene include an alkyl group, an alkoxy group, a halogen atom, and a halogenated alkyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and further preferably a methoxy group or an ethoxy group. The halogen atom as the substituent is preferably a fluorine atom. Examples of the halogenated alkyl group as the substituent include the alkyl groups in which some or all of the hydrogen atoms of the alkyl groups are substituted with the halogen atoms. The substituent that substitutes the hydrogen atom on the benzene ring of styrene is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0172] The structural unit (st) is preferably a structural unit derived from styrene, or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of styrene is substituted with an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, more preferably a structural unit derived from styrene, or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of styrene is substituted with a methyl group, and even more preferably a structural unit derived from styrene.

[0173] The structural unit (st) contained in the component (A1) may be of one type, or two or more types. When the component (A1) contains the structural unit (st), the proportion of the structural unit (st) is preferably 1 to 30 mol %, and more preferably 1 to 20 mol %, based on the total (100 mol %) of all structural units constituting the component (A1).

[0174] The component (A1) contained in the resist composition of this embodiment may use either a single type, or a combination of two or more types. In the resist composition of this embodiment, the component (A1) can be a polymeric compound that has a repeating structure of the structural unit (a1). A preferred example of the component (A1) is a polymeric compound having a repeating structure of the structural unit (a1) and the structural unit (a2).

[0175] In a polymer compound having a repeating structure of the structural unit (a1) and the structural unit (a2), the proportion of the structural unit (a1) in the polymer compound is preferably 5 to 90 mol %, more preferably 5 to 80 mol %, even more preferably 10 to 70 mol %, and particularly preferably 10 to 60 mol %, relative to the total (100 mol %) of all structural units constituting the polymer compound. In a polymer compound having a repeating structure of the structural unit (a1) and the structural unit (a2), the proportion of the structural unit (a2) in the polymer compound is preferably 10 to 95 mol %, more preferably 20 to 95 mol %, even more preferably 30 to 90 mol %, and particularly preferably 40 to 90 mol %, relative to the total (100 mol %) of all structural units constituting the polymer compound.

[0176] The component (A1) can be produced by dissolving monomers from which each structural unit is derived in a polymerization solvent, and then adding a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate (e.g., V-601), and polymerizing the resulting mixture. Alternatively, the component (A1) can be produced by dissolving a monomer that derives the structural unit (a1) and, if necessary, a monomer that derives a structural unit other than the structural unit (a1) (for example, a monomer that derives the structural unit (a2)) in a polymerization solvent, adding the above-mentioned radical polymerization initiator to the resulting mixture to polymerize, and then carrying out a deprotection reaction. In addition, during polymerization, for example, HS-CH 2 -CH 2 -CH 2 -C(CF 3 ) 2By using a chain transfer agent such as -OH in combination, the chain can be terminated with -C(CF 3 ) 2 A -OH group may be introduced. In this way, a copolymer having a hydroxyalkyl group, in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms, is effective in reducing development defects and reducing LER (line edge roughness: non-uniform unevenness on the line sidewall).

[0177] The weight average molecular weight (Mw) of the component (A1) (based on polystyrene conversion by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 2,000 to 30,000, and even more preferably 3,000 to 20,000. When the Mw of the component (A1) is no more than the preferred upper limit of this range, the compound has sufficient solubility in a resist solvent for use as a resist, and when it is no less than the preferred lower limit of this range, the dry etching resistance and cross-sectional shape of the resist pattern are excellent. The dispersity (Mw / Mn) of the component (A1) is not particularly limited, but is preferably from 1.0 to 4.0, more preferably from 1.0 to 3.0, and particularly preferably from 1.0 to 2.0, where Mn represents the number average molecular weight.

[0178] Regarding component (A2) The resist composition of this embodiment may use, in combination with the component (A), a base component (hereafter referred to as “component (A2)”) that does not fall under the category of the component (A1) above and whose solubility in a developer changes under the action of an acid. There are no particular restrictions on the component (A2), and it may be selected from the many conventional base components for chemically amplified resist compositions. The component (A2) may be a polymeric compound or a low molecular weight compound, and may be used either alone or in combination of two or more.

[0179] The proportion of the (A1) component in the (A) component is preferably 25% by mass or more, more preferably 50% by mass or more, and even more preferably 75% by mass or more, and may be 100% by mass, based on the total mass of the (A) component. When the proportion is 25% by mass or more, a resist pattern that is excellent in various lithography properties such as high sensitivity, resolution, and improved roughness is easily formed.

[0180] The amount of the component (A) in the resist composition of this embodiment may be adjusted depending on factors such as the thickness of the resist film to be formed.

[0181] <Base component (D)> The resist composition of this embodiment contains a base component (hereafter referred to as "component (D)"). The component (D) acts as a quencher (acid diffusion controller) that traps acid generated in the resist composition upon exposure. The resist composition of this embodiment contains components (D01) and (D02) as the component (D).

[0182] ≪(D01) Component≫ The component (D01) is a compound represented by the following general formula (d01-1).

[0183] [ka] [In the formula, Rd 01 is an optionally substituted cyclic group, an optionally substituted chain alkyl group, or an optionally substituted chain alkenyl group; m is an integer of 1 or more, m+ are each independently an organic cation having a valence of m.

[0184] In the resist composition of this embodiment, the component (D01) acts as a quencher (acid diffusion controller) that traps acid generated by exposure. By using the component (D01) in combination with the components (D02) and (F01) described below, it is possible to achieve both high sensitivity of the resist composition and reduced roughness of the resist pattern formed using the resist composition.

[0185] Anion section In formula (d01-1), Rd 01 represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

[0186] Optionally substituted cyclic groups: Rd 01 The cyclic group in is preferably a cyclic hydrocarbon group. The cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

[0187] Rd 01 The aromatic hydrocarbon group in the formula (I) is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, further preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Rd 01 Specific examples of the aromatic ring of the aromatic hydrocarbon group in the above formula include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms, etc. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Rd 01Specific examples of the aromatic hydrocarbon group in [reference] include a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), a group in which one hydrogen atom of the aromatic ring is substituted with an alkylene group (for example, arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0188] Rd 01 The cyclic aliphatic hydrocarbon group in [reference] includes an aliphatic hydrocarbon group containing a ring in its structure. Examples of the aliphatic hydrocarbon group containing a ring in this structure include an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 20, and more preferably 3 to 12. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane, cyclohexane, etc. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, as the polycycloalkane, polycycloalkanes having a crosslinked ring system polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane; polycycloalkanes having a condensed ring system polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferred.

[0189] Among them, Rd 01The cyclic aliphatic hydrocarbon group in is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, particularly preferably an adamantyl group or a norbornyl group, and most preferably an adamantyl group.

[0190] The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, specifically, a methylene group [-CH 2 -], ethylene group [-(CH 2 ) 2 -], trimethylene group [-(CH 2 ) 3 -], tetramethylene group [-(CH 2 ) 4 -], pentamethylene group [-(CH 2 ) 5 -] etc. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, specifically, -CH(CH 3 )-, -CH(CH 2 CH 3 )-, -C(CH 3 ) 2 -, -C(CH 3 )(CH 2 CH 3 )-, -C(CH 3 )(CH 2 CH 2 CH 3 )-, -C(CH 2 CH 3 ) 2 -, etc. alkylmethylene groups; -CH(CH 3 )CH 2 -, -CH(CH 3 )CH(CH 3 )-, -C(CH 3 ) 2 CH 2 -, -CH(CH 2CH 3 )CH 2 -, -C(CH 2 CH 3 ) 2 -CH 2 -, etc. alkyl ethylene groups; -CH(CH 3 )CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 -, etc.; -CH(CH 3 )CH 2 CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 CH 2 The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0191] Also, Rd 01 The cyclic hydrocarbon group in may contain a heteroatom, such as a heterocycle. Specifically, the lactone-containing cyclic groups represented by the general formulae (a2-r-1) to (a2-r-7) and the —SO 2 -containing cyclic groups, and other heterocyclic groups represented by the following chemical formulas (r-hr-1) to (r-hr-16), respectively, in which * represents a bond bonded to a carbon atom in formula (d01-1).

[0192] [ka]

[0193] Rd 01 The cyclic hydrocarbon group in may have a substituent, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, etc. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group. The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and most preferably a methoxy group or an ethoxy group. As the halogen atom as a substituent, a fluorine atom is preferred. Examples of halogenated alkyl groups as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms. The carbonyl group as a substituent is a methylene group (-CH 2 -) is a group that substitutes

[0194] A chain alkyl group which may have a substituent: Rd 01 The chain alkyl group in may be either linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably has 1 to 15 carbon atoms, and most preferably has 1 to 10 carbon atoms. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably has 3 to 15 carbon atoms, and most preferably has 3 to 10 carbon atoms. Specific examples include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0195] An optionally substituted chain alkenyl group: Rd 01The chain alkenyl group in may be either linear or branched. The linear alkenyl group preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, further preferably 2 to 4 carbon atoms, and particularly preferably 3 carbon atoms. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. The branched alkenyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms, further preferably 3 to 4 carbon atoms, and particularly preferably 3. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group. Of the above chain alkenyl groups, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0196] Rd 01 The chain-like alkyl or alkenyl group in may have a substituent. Examples of the substituent include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, the above-mentioned Rd 01 and the like.

[0197] Rd 01 In addition to those mentioned above, the optionally substituted cyclic group, the optionally substituted chain alkyl group, or the optionally substituted chain alkenyl group also includes the same as the acid-dissociable group represented by formula (a1-r-2) above as the optionally substituted cyclic group or the optionally substituted chain alkyl group.

[0198] Among them, Rd 01is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, for example, a phenyl group, a naphthyl group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane; a lactone-containing cyclic group represented by each of the general formulae (a2-r-1) to (a2-r-7) above; -SO represented by each of the general formulae (a5-r-1) to (a5-r-4) above; 2 -containing cyclic groups and the like are preferred. Among these, Rd 01 is preferably an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain-like alkyl group which may have a substituent. The substituents which these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluorinated alkyl group, a lactone-containing cyclic group represented by each of the above general formulas (a2-r-1) to (a2-r-7), an ether bond, an ester bond, or a combination thereof. When the substituent contains an ether bond and / or an ester bond, these may be bonded to the alkylene group. For example, the substituent may contain a linking group represented by any of the following formulas (y-al-1) to (y-al-5).

[0199] [ka] [In the formula, V' 101 is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' 102 is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.

[0200] Suitable examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and other ring structures). The aromatic hydrocarbon group preferably has a hydroxyl group as a substituent. The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. The chain alkyl group preferably has 1 to 10 carbon atoms. Specific examples of the chain alkyl group include linear alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group; and branched alkyl groups such as a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0201] When the chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the number of carbon atoms in the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and further preferably 1 to 4. The fluorinated alkyl group may contain an atom other than a fluorine atom. Examples of the atom other than a fluorine atom include an oxygen atom, a sulfur atom, and a nitrogen atom.

[0202] Among them, Rd 01 As the alkyl group, an aromatic hydrocarbon group which may have a substituent or a chain-like alkyl group which may have a substituent is preferable, and an aromatic hydrocarbon group which may have a substituent or a chain-like fluorinated alkyl group which may have a substituent is more preferable.

[0203] Preferred specific examples of the anion moiety of component (D01) are shown below, but the invention is not limited to these.

[0204] [ka]

[0205] [ka]

[0206] Among the above, the anion portion of the (D01) component is preferably represented by any one of the chemical formulas (an-d01-1) to (an-d01-7), and (an-d01-19) to (an-d01-23), and more preferably represented by any one of the chemical formulas (an-d01-1) to (an-d01-4), and (an-d01-21).

[0207] ·Cation part In formula (d01-1), M m+ is an organic cation with a valence of m. m+ is preferably a sulfonium cation or an iodonium cation, and m is an integer of 1 or more.

[0208] Preferred cationic moieties ((M m+ ) 1 / m ) include organic cations represented by the following general formulas (ca-1) to (ca-5), respectively.

[0209] [ka] [In the formula, R 201 ~R 207 , and R 211 ~R 212 R each independently represents an aryl group, an alkyl group, or an alkenyl group which may have a substituent. 201 ~R 203 , R 206 ~R 207 , R 211 ~R 212 may be bonded to each other to form a ring together with the sulfur atom in the formula. 208 ~R 209 R each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 210 is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an SO 2 -containing cyclic group. 201 represents -C(=O)- or -C(=O)-O-. 201each independently represents an arylene group, an alkylene group, or an alkenylene group; x is 1 or 2. W 201 represents a (x+1)-valent linking group.

[0210] In the above general formulas (ca-1) to (ca-5), R 201 ~R 207 , and R 211 ~R 212 The aryl group in the formula (I) may be an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group or a naphthyl group is preferred. R 201 ~R 207 , and R 211 ~R 212 The alkyl group in is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms. R 201 ~R 207 , and R 211 ~R 212 The alkenyl group in the formula (I) preferably has 2 to 10 carbon atoms. R 201 ~R 207 , and R 210 ~R 212 Examples of the substituent that may be possessed by the group include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and groups represented by the following general formulas (ca-r-1) to (ca-r-7).

[0211] [ka] [In the formula, R' 201 are each independently a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

[0212] In the formulae (ca-r-1) to (ca-r-7), R' 201R' each independently represents a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. 201 The optionally substituted cyclic group, the optionally substituted chain alkyl group, or the optionally substituted chain alkenyl group in the formula (d01-1) is, respectively, Rd 01 The same can be mentioned.

[0213] Among them, R' 201 is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, for example, a phenyl group, a naphthyl group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane; a lactone-containing cyclic group represented by each of the general formulae (a2-r-1) to (a2-r-7) above; -SO represented by each of the general formulae (a5-r-1) to (a5-r-4) above; 2 -containing cyclic groups and the like are preferred.

[0214] In the above general formulas (ca-1) to (ca-5), R 201 ~R 203 , R 206 ~R 207 , R 211 ~R 212 When they are bonded to each other to form a ring together with the sulfur atom in the formula, they are not included in the heteroatoms such as sulfur atoms, oxygen atoms, and nitrogen atoms, as well as in the carbonyl groups, -SO-, -SO 2 -, -SO 3 -, -COO-, -CONH- or -N(R N )-(applicable R Nis an alkyl group having 1 to 5 carbon atoms.) may be bonded via a functional group. As for the ring formed, one ring containing a sulfur atom in its ring skeleton in the formula is preferably a 3- to 10-membered ring including the sulfur atom, and particularly preferably a 5- to 7-membered ring. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring.

[0215] R 208 ~R 209 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when they are alkyl groups they may be bonded to each other to form a ring.

[0216] R 210 is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an SO 2 -containing cyclic group. R 210 The aryl group in the formula (I) may be an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group or a naphthyl group is preferred. R 210 The alkyl group in is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms. R 210 The alkenyl group in the formula (I) preferably has 2 to 10 carbon atoms. R 210 In the formula (I), optionally substituted SO 2 Examples of the --containing cyclic group include "-SO 2 -containing polycyclic group" is preferred, and a group represented by the above general formula (a5-r-1) is more preferred.

[0217] Y 201 each independently represents an arylene group, an alkylene group, or an alkenylene group. Y 201 The arylene group in the above formula (b-1) is 101 Examples of the aromatic hydrocarbon group in the above formula include groups in which one hydrogen atom has been removed from the aryl groups exemplified above. Y 201 The alkylene group and alkenylene group in the above formula (b-1) are 101 Examples of the chain alkyl group and the chain alkenyl group in the above formula (1) include groups in which one hydrogen atom has been removed from the groups exemplified as the chain alkyl group and the chain alkenyl group in the above formula (1).

[0218] In the above formula (ca-4), x is 1 or 2. W 201 is a (x+1)-valent linking group, that is, a divalent or trivalent linking group. W 201 The divalent linking group in the above formula (a2-1) is preferably a divalent hydrocarbon group which may have a substituent. 21 Examples of the divalent hydrocarbon groups which may have a substituent include those shown in the above. 201 The divalent linking group in may be linear, branched, or cyclic, and is preferably cyclic. Among them, a group in which two carbonyl groups are combined at both ends of an arylene group is preferred. Examples of the arylene group include a phenylene group and a naphthylene group, and the phenylene group is particularly preferred. W 201 The trivalent linking group in 201 and a group in which one hydrogen atom has been removed from the divalent linking group represented by the formula: W 201 As the trivalent linking group in the formula (I), a group in which two carbonyl groups are bonded to an arylene group is preferable.

[0219] Specific examples of suitable cations represented by the above formula (ca-1) include cations represented by the following chemical formulas (ca-1-1) to (ca-1-70).

[0220] [ka]

[0221] [ka]

[0222] [ka] [In the formula, g1, g2, and g3 each represent a repeating number, where g1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20.]

[0223] [ka]

[0224] [ka]

[0225] [ka] [In the formula, R” 201 is a hydrogen atom or a substituent, and the substituent is the above-mentioned R 201 ~R 207 , and R 210 ~R 212 The substituents are the same as those exemplified as the substituents that may be possessed by the

[0226] Specific examples of suitable cations represented by the formula (ca-2) include diphenyliodonium cation, bis(4-tert-butylphenyl)iodonium cation, and the like.

[0227] Specific examples of suitable cations represented by the formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

[0228] [ka]

[0229] Specific examples of suitable cations represented by the formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

[0230] [ka]

[0231] Specific examples of suitable cations represented by the formula (ca-5) include cations represented by the following general formulas (ca-5-1) to (ca-5-3).

[0232] [ka]

[0233] Among the above, the cationic part ((M m+ ) 1 / m ) is preferably a cation represented by general formula (ca-1), more preferably a cation represented by each of the above formulas (ca-1-1) to (ca-1-70), and even more preferably a cation represented by each of the above formulas (ca-1-1) to (ca-1-47).

[0234] The component (D01) is preferably a compound represented by the following formula (d01-1-1).

[0235] [ka]

[0236] [In the formula, Rd 01 is Rd in the formula (d01-1). 01 Same as R 201 ~R 203 is R in the above formula (ca-1). 201 ~R 203 is the same as:

[0237] In the above formula (d01-1-1), Rd 01is preferably an aromatic hydrocarbon group which may have a substituent, or a linear alkyl group which may have a substituent, and more preferably an aromatic hydrocarbon group which may have a substituent, or a fluorinated alkyl group which may have a substituent. In the above formula (d01-1-1), R 201 ~R 203 is each independently preferably an aryl group which may have a substituent.

[0238] Specific examples of the component (D01) are shown below, but are not limited thereto.

[0239]

Chemical formula

[0240] In the resist composition of the present embodiment, the component (D01) may be used alone or in combination of two or more. In the resist composition of the present embodiment, the content of the component (D01) is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, and still more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the component (A1). When the content of the component (D01) is equal to or higher than the lower limit value of the above preferred range, the roughness of the resist pattern is more likely to be reduced. On the other hand, when it is equal to or lower than the upper limit value of the above preferred range, the sensitivity of the resist composition is likely to be maintained well.

[0241] Production method of the component (D01): The production method of the above-mentioned component (D01) is not particularly limited, and it can be produced by a known method.

[0242] ≪Component (D02)≫ The component (D02) is a compound represented by the following general formula (d02-1).

[0243]

Chemical formula

[0244] In the resist composition of this embodiment, the component (D02) acts as a quencher (acid diffusion controller) that traps acid generated by exposure. By using the component (D02) in combination with the above-mentioned component (D02) and the component (F01) described below, it is possible to achieve both high sensitivity of the resist composition and reduced roughness of the resist pattern formed using the resist composition.

[0245] Anion section In the above formula (d02-1), Rd 02 represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

[0246] As the cyclic group which may have a substituent, Rd in the above formula (d01-1) 01 The cyclic group may be the same as the cyclic group optionally having a substituent in the above formula (1). However, Rd 02 In the above, the carbon atom adjacent to the S atom does not have a fluorine atom bonded thereto (is not substituted with fluorine). This makes the anion of the (D02) component an appropriate weak acid anion, improving the quenching ability. Rd 02is preferably a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent. The chain alkyl group preferably has 1 to 10 carbon atoms, and more preferably has 3 to 10 carbon atoms. The aliphatic cyclic group preferably has 3 to 20 carbon atoms, and more preferably has 6 to 15 carbon atoms. The aliphatic cyclic group is preferably a group (which may have a substituent) in which one or more hydrogen atoms have been removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like; more preferably a group in which one or more hydrogen atoms have been removed from camphor, or the like. Rd 02 The hydrocarbon group may have a substituent. Examples of the substituent include Rd 01 Examples of the substituent include the same as the substituents that may be possessed by the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in the above.

[0247] Among them, Rd 02 As the alkyl group, an aliphatic cyclic group which may have a substituent is preferable, and an aliphatic polycyclic group which may have a substituent is more preferable.

[0248] Preferred specific examples of the anion moiety of component (D02) are shown below, but the invention is not limited to these.

[0249] [ka]

[0250] Among the above, the anion portion of the (D02) component is preferably represented by any one of chemical formulas (an-d02-1) to (an-d02-19), more preferably by chemical formulas (an-d02-1) to (an-d02-8), and even more preferably by chemical formulas (an-d02-1), (an-d02-6), or (an-d02-8).

[0251] ·Cation part In formula (d02-1), M m+is an organic cation with a valence of m. m+ As the formula, M in the formula (d1-1) m+ The same can be mentioned.

[0252] The cationic portion of the (D02) component ((M m+ ) 1 / m As the cationic moiety ((M)), the organic cations represented by the above formulas (ca-1) to (ca-5) are preferred, and the cation represented by the above formula (ca-1) is more preferred. m+ ) 1 / m ) are preferably cations represented by the above formulas (ca-1-1) to (ca-1-70), respectively, and more preferably cations represented by the above formulas (ca-1-1) to (ca-1-47), respectively.

[0253] The compound (D02) is preferably a compound represented by the following formula (d02-1-1).

[0254] [ka]

[0255] [In the formula, Rd 02 is Rd in the formula (d02-1). 02 Same as R 201 ~R 203 is R in the above formula (ca-1). 201 ~R 203 is the same as:

[0256] In the above formula (d02-1-1), Rd 02 is preferably a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent, and more preferably an aliphatic cyclic group which may have a substituent. In the above formula (d02-1-1), R 201 ~R 203 are preferably each independently an aryl group which may have a substituent.

[0257] Specific examples of component (D02) are shown below, but are not limited to these.

[0258] [ka]

[0259] In the resist composition of this embodiment, the component (D02) may use either a single type, or a combination of two or more types. The content of the component (D02) in the resist composition of this embodiment is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the component (A1). When the amount of the component (D02) is at least as large as the lower limit of the above-mentioned preferred range, the roughness of the resist pattern is likely to be reduced further, while when the amount is no more than the upper limit of the above-mentioned preferred range, the sensitivity of the resist composition is likely to be maintained at an excellent level. The mass ratio of the component (D01) to the component (D02) in the resist composition of this embodiment is not particularly limited, but can be, for example, a mass ratio of the component (D01):the component (D02) of 1:1 to 5:1. The mass ratio of the component (D01):the component (D02) is preferably 1.5:1 to 4:1, and more preferably 2:1 to 3:1. When the mass ratio of the component (D01) to the component (D02) falls within the above preferred range, the sensitivity of the resist composition is likely to be improved and the roughness of the resist pattern is likely to be reduced.

[0260] Manufacturing method of component (D02): There are no particular limitations on the method for producing the component (D02), and it can be produced by any known method.

[0261] <Other (D) Ingredients> The resist composition of this embodiment may contain a component (D) other than the components (D01) and (D02) as long as the effect of the present invention is not impaired. Examples of the component (D) other than the components (D01) and (D02) include a photodecomposable base (D1) (hereinafter referred to as "component (D1)") that decomposes upon exposure and loses its acid diffusion controllability (excluding those corresponding to the components (D01) and (D01)), a nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") that does not fall under the category of the component (D1), and the like.

[0262] Component (D1) Examples of the component (D1) include compounds represented by the following general formula (d1-3) (hereinafter referred to as "component (d1-3)").

[0263] [ka] [In the formula, Rd 4 represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. 1 is a single bond or a divalent linking group; m is an integer of 1 or more; M m+ are each independently an organic cation having a valence of m.

[0264] Anion section In formula (d1-3), Rd 3 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and R' 201 The Rd is preferably a fluorine atom-containing cyclic group, a chain alkyl group, or a chain alkenyl group. Among these, a fluorinated alkyl group is preferred, and the Rd 1 More preferred are the same fluorinated alkyl groups as those mentioned above.

[0265] In formula (d1-3), Rd 4 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the R' 201The same can be mentioned. Among these, an alkyl group, an alkoxy group, an alkenyl group, or a cyclic group, which may have a substituent, is preferable. Rd 4 The alkyl group in Rd is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. 4 A part of the hydrogen atoms of the alkyl group may be substituted with a hydroxyl group, a cyano group, or the like. Rd 4 The alkoxy group in is preferably an alkoxy group having 1 to 5 carbon atoms, and specific examples of the alkoxy group having 1 to 5 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group. Of these, a methoxy group and an ethoxy group are preferred.

[0266] Rd 4 The alkenyl group in R' 201 Examples of the alkenyl group include the same as the alkenyl group in the above, and a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group, and a 2-methylpropenyl group are preferred. These groups may further have an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms as a substituent.

[0267] Rd 4 The cyclic group in R' 201 Examples of the cyclic groups include those similar to those in the above formula, and preferred are alicyclic groups obtained by removing one or more hydrogen atoms from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane, or aromatic groups such as a phenyl group or a naphthyl group. 4 When Rd is an alicyclic group, the resist composition dissolves well in an organic solvent, and the lithography properties become good. 4When is an aromatic group, in lithography using EUV or the like as an exposure light source, the resist composition exhibits excellent light absorption efficiency and exhibits favorable sensitivity and lithography properties.

[0268] In formula (d1-3), Yd 1 is a single bond or a divalent linking group. Yd 1 The divalent linking group in is not particularly limited, but examples thereof include a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, and a divalent linking group containing a hetero atom. 21 Examples of the divalent linking group include the same divalent hydrocarbon group which may have a substituent and the divalent linking group containing a hetero atom as mentioned in the description of the divalent linking group in the above. Yd 1 is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, and further preferably a methylene group or an ethylene group.

[0269] Preferred specific examples of the anion moiety of the component (d1-3) are shown below.

[0270] [ka]

[0271] [ka]

[0272] ··Cation part In formula (d1-3), M m+ is an m-valent organic cation, and M in the formula (d01-1) m+ is the same as:

[0273] The component (d1-3) may be used alone or in combination of two or more.

[0274] Manufacturing method of component (d1-3): The method for producing the component (d1-3) is not particularly limited, and it can be produced, for example, in a manner similar to that described in US2012-0149916.

[0275] In the resist composition of this embodiment, the component (D1) may use either a single type, or a combination of two or more types. When the resist composition of this embodiment contains the component (D1), the content of the component (D1) in the resist composition is preferably 10 mass% or less, more preferably 5 mass% or less, and even more preferably 3 mass% or less, based on the total mass of the component (D). It is particularly preferable that the resist composition of this embodiment does not contain the component (D1). By keeping the content of the component (D1) at or below the preferred upper limit, the effects of the present invention are more easily achieved.

[0276] ·(D2) component The component (D2) is a nitrogen-containing organic compound component that does not fall under the category of a photodegradable base. The component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not fall under the category of a photodegradable base, and any known base may be used. Among these, aliphatic amines are preferred, and among these, secondary aliphatic amines and tertiary aliphatic amines are more preferred. An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms. The aliphatic amine is ammonia NH 3 Examples of the amine include amines in which at least one hydrogen atom is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms (alkylamines or alkyl alcohol amines), and cyclic amines. Specific examples of alkylamines and alkyl alcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkyl alcohol amines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 5 to 10 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine is particularly preferred.

[0277] Examples of cyclic amines include heterocyclic compounds containing a nitrogen atom as a heteroatom. The heterocyclic compounds may be monocyclic (aliphatic monocyclic amines) or polycyclic (aliphatic polycyclic amines). Specific examples of the aliphatic monocyclic amine include piperidine and piperazine. The aliphatic polycyclic amine is preferably one having 6 to 10 carbon atoms, and specific examples thereof include 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5.4.0]-7-undecene, hexamethylenetetramine, and 1,4-diazabicyclo[2.2.2]octane.

[0278] Other aliphatic amines include tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxyethoxymethoxy)ethyl}amine, tris{2-(1-methoxyethoxy)ethyl}amine, tris{2-(1-ethoxyethoxy)ethyl}amine, tris{2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-(2-hydroxyethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, and the like, with triethanolamine triacetate being preferred.

[0279] Furthermore, an aromatic amine may be used as the component (D2). Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, and N-tert-butoxycarbonylpyrrolidine.

[0280] The component (D2) may be used alone or in combination of two or more types. When the resist composition of this embodiment contains the component (D2), the content of the component (D1) in the resist composition is preferably 10 mass% or less, more preferably 5 mass% or less, and even more preferably 3 mass% or less, based on the total mass of the component (D). It is particularly preferable that the resist composition of this embodiment does not contain the component (D2). By keeping the content of the component (D2) at or below the preferred upper limit, the effects of the present invention are more easily achieved.

[0281] <Fluorine additive component (F)> The resist composition of the present embodiment contains a fluorine additive component (hereafter referred to as "component (F)"). The component (F) imparts water repellency to the resist film and / or improves lithography properties. The resist composition of the present embodiment contains component (F01) as the component (F).

[0282] (F01) component The component (F01) is a polymeric compound having a structural unit (f01) represented by general formula (f01-1) below and a structural unit (f02) represented by general formula (f02-1) below.

[0283] [ka] [In the formula, each R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; 01 is a divalent linking group; Rf 01 is a monovalent organic group containing a fluorine atom; Vf 02 is a divalent linking group; nf 02 is an integer from 0 to 2; Rf 02 is an acid-dissociable group.

[0284] In the resist composition of this embodiment, the component (F01) acts as a fluorine additive component. By using the component (F01) in combination with the components (D01) and (D02), it is possible to achieve both high sensitivity of the resist composition and reduced roughness of the resist pattern formed using the resist composition.

[0285] <Constituent unit (f01)> The structural unit (f01) is a structural unit represented by general formula (f01-1) shown below.

[0286] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; 01 is a divalent linking group; Rf 01 is a monovalent organic group containing a fluorine atom.

[0287] In the formula (f01-1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R is the same as R in the formula (a1-1). R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is particularly preferable.

[0288] In the above formula (f01-1), Vf 01 is a divalent linking group. The divalent linking group is not particularly limited, but examples thereof include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom. 01 The divalent hydrocarbon group which may have a substituent and the divalent linking group which contains a hetero atom in the above formula (a10-1) are each preferably selected from the group consisting of Ya x1 Examples of the above-mentioned examples are as follows.

[0289] Among them, Vf 01 is preferably a divalent hydrocarbon group which may have a substituent. The divalent hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably has 1 to 6 carbon atoms, and further preferably has 1 to 3 carbon atoms. The divalent hydrocarbon group is preferably an aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be saturated or unsaturated, but is preferably saturated. The aliphatic hydrocarbon group is preferably linear or branched, and more preferably linear.

[0290] Vf 01 The divalent hydrocarbon group in may have a substituent. Examples of the substituent include a halogen atom, and a fluorine atom is preferable.

[0291] Vf 01 As the alkyl group, an alkylene group having 1 to 3 carbon atoms is preferable, and a methylene group or an ethylene group is more preferable.

[0292] In the formula (f01-1), Rf 01is a monovalent organic group containing a fluorine atom. The monovalent organic group containing a fluorine atom can be a monovalent hydrocarbon group containing a fluorine atom. The monovalent hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0293] Rf 01 Aliphatic hydrocarbon groups in The aliphatic hydrocarbon group may be saturated or unsaturated, but is preferably saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, and aliphatic hydrocarbon groups containing a ring in the structure.

[0294] Linear or branched aliphatic hydrocarbon groups The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkyl group is preferable, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. The branched aliphatic hydrocarbon group preferably has 3 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and particularly preferably 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkyl group is preferable, and specific examples thereof include an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.

[0295] The linear or branched aliphatic hydrocarbon group contains at least one fluorine atom as a substituent. The linear or branched aliphatic hydrocarbon group is preferably such that 25% or more of the hydrogen atoms in the aliphatic hydrocarbon group are fluorinated, more preferably 50% or more, and even more preferably 60% or more. By fluorinating at least the preferred upper limit, the hydrophobicity of the resist film during immersion exposure is improved. The linear or branched aliphatic hydrocarbon group may contain a substituent other than a fluorine atom, such as a hydroxyl group or a halogen atom other than fluorine (e.g., a chlorine atom, a bromine atom, an iodine atom, etc.).

[0296] Aliphatic hydrocarbon groups containing rings in the structure Examples of the aliphatic hydrocarbon group containing a ring in its structure include a cyclic aliphatic hydrocarbon group (a group in which one hydrogen atom has been removed from an aliphatic hydrocarbon ring) which may contain a substituent containing a heteroatom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.

[0297] The cyclic aliphatic hydrocarbon group contains at least one fluorine atom as a substituent. In the cyclic aliphatic hydrocarbon group, preferably 25% or more of the hydrogen atoms in the cyclic hydrocarbon group are fluorinated, more preferably 50% or more, and even more preferably 60% or more. The cyclic aliphatic hydrocarbon group may contain a substituent other than a fluorine atom, such as a hydroxyl group, a halogen atom other than fluorine (e.g., a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group, an alkoxy group, a carbonyl group, etc. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and further preferably a methoxy group or an ethoxy group. Examples of the halogenated alkyl group as the substituent include the alkyl groups in which some or all of the hydrogen atoms of the alkyl groups are substituted with the halogen atoms. In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. Examples of the substituent containing a hetero atom include -O-, -C(=O)-O-, -S-, -S(=O) 2 -, -S(=O) 2 -O- is preferred.

[0298] Rf 01 Aromatic hydrocarbon groups in The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is replaced with a heteroatom. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Specific examples of the aromatic hydrocarbon group include a group in which one hydrogen atom is removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); a group in which one hydrogen atom is removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The number of carbon atoms of the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0299] The aromatic hydrocarbon group contains at least one fluorine atom as a substituent, and preferably has 25% or more, more preferably 50% or more, and even more preferably 60% or more of the hydrogen atoms in the aromatic hydrocarbon group fluorinated. The aromatic hydrocarbon group may contain a substituent other than a fluorine atom, such as an alkyl group, an alkoxy group, a halogen atom other than a fluorine atom (e.g., a chlorine atom, a bromine atom, an iodine atom, etc.), and a hydroxyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Examples of the alkoxy group as the substituent include those exemplified as the substituent substituting a hydrogen atom in the cyclic aliphatic hydrocarbon group.

[0300] Rf 01 As the alkyl group, an aliphatic hydrocarbon group containing a fluorine atom is preferable, and an alkyl group containing a fluorine atom is more preferable. The alkyl group preferably has 1 to 6 carbon atoms, more preferably has 1 to 3 carbon atoms, and further preferably has 1 or 2 carbon atoms. Among them, Rf 01 is preferably a fluorinated alkyl group having 1 to 6 carbon atoms, and more preferably a trifluoromethyl group, -CH 2 -CF 3 , -CH 2 -CF 2 -CF 3 , -CH(CF 3 ) 2 , -CH 2 -CH 2 -CF 3 , or -CH 2 -CH 2 -CF 2 -CF 2 -CF 2 -CF 3 is more preferred.

[0301] The structural unit (f01) is preferably a structural unit represented by general formula (f01-1-1) shown below.

[0302] [ka] [In the formula, R is as defined above; Rf 012 and Rf 013 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; Rf 011 represents an organic group containing a fluorine atom.

[0303] In the above formula (f01-1-1), R is the same as R in the above formula (f01-1-).

[0304] In the above formula (f01-1-1), Rf 012 and Rf 013Rf each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. The halogen atom is preferably a fluorine atom. The alkyl group having 1 to 5 carbon atoms is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group. 102 and Rf 103 Examples of the halogenated alkyl group having 1 to 5 carbon atoms include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is preferred. Among these, Rf 012 and Rf 013 is preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group.

[0305] In formula (f01-1-1), Rf 011 is an organic group containing a fluorine atom. 011 is Rf in the formula (f0-1). 01 is the same as:

[0306] Specific examples of the structural unit (f01) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0307] [ka]

[0308] The structural unit (f01) contained in the component (F01) may be of one type, or two or more types. The proportion of the structural unit (f01) in the component (F01) relative to the total (100 mol%) of all structural units constituting the component (F01), is preferably 10 to 95 mol%, more preferably 20 to 90 mol%, even more preferably 30 to 85 mol%, and particularly preferably 40 to 80 mol%. When the proportion of the structural unit (f01) is at least as large as the lower limit of the aforementioned preferred range, the sensitivity of the resist composition is improved, and lithography properties such as roughness are further improved. When the proportion of the structural unit (f01) is at most the upper limit of the aforementioned preferred range, a balance with the other structural units can be achieved, and various lithography properties become favorable.

[0309] <Constituent units (f02)> The structural unit (f02) is a structural unit represented by general formula (f02-1) shown below.

[0310] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; 02 is a divalent linking group; nf 02 is an integer from 0 to 2; Rf 02 is an acid-dissociable group.

[0311] In the formula (f02-1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R is the same as R in the formula (a1-1). R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is particularly preferable.

[0312] In the above formula (f02-1), Vf 02 is a divalent linking group. The divalent linking group is not particularly limited, but examples thereof include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom. 01 The divalent hydrocarbon group which may have a substituent and the divalent linking group which contains a hetero atom in the above formula (a10-1) are each preferably selected from the group consisting of Ya x1 Examples of the above-mentioned examples are as follows.

[0313] Among them, Vf 02A divalent hydrocarbon group which may have an ether bond is preferred. As the divalent hydrocarbon group which may have an ether bond, 1 to 10 carbon atoms are preferred, 1 to 6 carbon atoms are more preferred, and 1 to 3 carbon atoms are even more preferred. As the divalent hydrocarbon group, an aliphatic hydrocarbon group is preferred. The aliphatic hydrocarbon group may be saturated or unsaturated, but is preferably saturated. The aliphatic hydrocarbon group is preferably linear or branched, and more preferably linear.

[0314] Vf 02 As, an alkylene group having 1 to 3 carbon atoms is preferred, and a methylene group or an ethylene group is more preferred.

[0315] In the formula (f02-1), nf 02 is an integer of 0 to 2. nf 02 is preferably 0 or 1, and more preferably 0.

[0316] In the formula (f02-1), Rf 02 is an acid dissociable group. As the acid dissociable group, the groups exemplified as the acid dissociable group in the constitutional unit (a1) are exemplified, a tertiary alkyl ester type acid dissociable group is preferred, and the acid dissociable group represented by the formula (a1-r-2) is more preferred.

[0317] Among them, as the acid dissociable group in Rf 02 the acid dissociable group represented by the following general formula (Rf02-1) is preferred.

[0318]

Chemical formula

[0319] In the formula (Rf02-1), Rf021 ~Rf 023 are each independently a saturated aliphatic hydrocarbon group. Rf 021 ~Rf 023 The saturated aliphatic hydrocarbon group in the formula (I) includes a linear or branched alkyl group, or a cyclic saturated aliphatic hydrocarbon group. The linear alkyl group preferably has 1 to 10 carbon atoms, more preferably has 1 to 5 carbon atoms, further preferably has 1 to 4 carbon atoms, and particularly preferably has 1 or 2 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

[0320] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably has 3 to 5 carbon atoms. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, and is preferably an isopropyl group.

[0321] Rf 021 The cyclic saturated aliphatic hydrocarbon group in may be a polycyclic group or a monocyclic group. The saturated aliphatic hydrocarbon group that is a monocyclic group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The saturated aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0322] Rf 022 and Rf 023 may be bonded to each other to form a ring. 022 and Rf023 When forms a ring, examples of the acid-dissociable group represented by the formula (Rf02-1) include the group represented by the formula (Rf02-1-1) above. Rf 022 and Rf 023 are not bonded to each other and are independent saturated aliphatic hydrocarbon groups, examples of the acid-dissociable group represented by the formula (Rf02-1) include the group represented by the formula (Rf02-1-2) above.

[0323] [ka] [In the formula, Rf 024 R represents a linear or branched alkyl group having 1 to 12 carbon atoms. f025 is Rf 024 represents a group which, together with the carbon atom to which it is bonded, forms a saturated aliphatic cyclic group. In the formula, Rf 026 and Rf 027 Rf each independently represents a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. 028 is a saturated aliphatic hydrocarbon group. * represents a bond bonded to the oxygen atom in formula (f02-1).

[0324] In the above formula (Rf02-1-1), Rf 024 is a linear or branched alkyl group having 1 to 12 carbon atoms.

[0325] Rf 024 As the linear or branched alkyl group in Rf 021 ~Rf 023 Examples of the linear or branched alkyl group in the above formula (1) include the same as those exemplified as the linear or branched alkyl group in the above formula (1).

[0326] In the above formula (Rf02-1-1), Rf 025 (Rf 024 The saturated aliphatic cyclic group formed together with the carbon atom to which it is attached) may be polycyclic or monocyclic. The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Of these, monocyclic saturated alicyclic hydrocarbon groups are preferred, and specifically, a cyclopentyl group and a cyclohexyl group are more preferred, with a cyclopentyl group being even more preferred.

[0327] In the above formula (Rf02-1-2), Rf 026 and Rf 027 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. The monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms may be linear or branched, but is preferably linear. The monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms preferably has 1 to 6 carbon atoms, more preferably has 1 to 3 carbon atoms, and even more preferably has 1 or 2 carbon atoms. Specific examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a decyl group. Among them, Rf 026 and Rf 027 is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, further preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

[0328] In the above formula (Rf02-1-2), Rf 028 is a saturated aliphatic hydrocarbon group. Examples of the saturated aliphatic hydrocarbon group include a linear or branched alkyl group, and a saturated alicyclic hydrocarbon group.

[0329] Rf028 The linear alkyl group in the formula (I) preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

[0330] Rf 028 The branched alkyl group in the above formula (I) preferably has 3 to 10 carbon atoms, and more preferably has 3 to 5 carbon atoms. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, and is preferably an isopropyl group.

[0331] Rf 028 The saturated alicyclic hydrocarbon group in this case may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0332] Specific examples of the acid dissociable group represented by the formula (Rf02-1-1) include the groups represented by the formulas (r-pr-m1) to (r-pr-m17) and (r-pr-s1) to (r-pr-s20).

[0333] Specific examples of the acid dissociable group represented by the formula (Rf02-1-2) include the groups represented by the formulas (r-pr-cm1) to (r-pr-cm5), (r-pr-cs1) to (r-pr-cs3), and (r-pr-c1) to (r-pr-c3).

[0334] Specific examples of the structural unit (f02) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0335] [ka]

[0336] [ka]

[0337] [ka]

[0338] The structural unit (f02) contained in the component (F01) may be of one type, or two or more types. The proportion of the structural unit (f02) in the component (F01) is preferably 5 to 60 mol %, more preferably 10 to 50 mol %, even more preferably 10 to 40 mol %, and particularly preferably 20 to 30 mol %, based on the total (100 mol %) of all structural units constituting the component (F01). When the proportion of the structural unit (f02) is at least as large as the lower limit of the aforementioned preferred range, the sensitivity of the resist composition is improved, and lithography properties such as roughness are further improved. When the proportion of the structural unit (f02) is at most the upper limit of the aforementioned preferred range, a balance with the other structural units can be achieved, and various lithography properties become favorable.

[0339] The component (F01) may be used alone or in combination of two or more types. The component (F01) may be a polymeric compound having a repeating structure of the structural unit (f01) and the structural unit (f02). In this case, the molar ratio of the structural unit (f01) to the structural unit (f02) in the polymeric compound (structural unit (f01):structural unit (f02)) is preferably from 90:10 to 40:60, more preferably from 85:15 to 50:50, and even more preferably from 80:20 to 60:40.

[0340] The (F01) component may contain other structural units in addition to the structural units (f01) and (f02). Examples of the other structural units include structural units derived from acrylic acid or methacrylic acid. The component (F01) is preferably a polymeric compound having a repeating structure of the structural unit (f01) and the structural unit (f02).

[0341] The weight average molecular weight (Mw) of the component (F01) (based on polystyrene conversion by gel permeation chromatography) is preferably 1000 to 50000, more preferably 5000 to 40000, and even more preferably 10000 to 30000. When the Mw of the component (F01) is equal to or less than the upper limit of the above range, the solubility in a resist solvent is good. When the Mw of the component (F01) is equal to or more than the lower limit of the above range, the water repellency of the resist film is good. The dispersity (Mw / Mn) of the (F01) component is preferably from 1.0 to 5.0, more preferably from 1.0 to 3.0, and even more preferably from 1.0 to 2.5.

[0342] The content of the component (F01) in the resist composition is preferably 0.5 to 10 parts by mass, and more preferably 1 to 5 parts by mass, per 100 parts by mass of the component (A).

[0343] Specific examples of the component (F01) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0344] [ka]

[0345] Other (F) ingredients The resist composition of this embodiment may contain a component (F) other than the component (F01) (hereafter referred to as "component (F1)") as long as the effects of the present invention are not impaired. As the component (F1), for example, fluorine-containing polymeric compounds described in JP-A-2010-002870, JP-A-2010-032994, JP-A-2010-277043, JP-A-2011-13569, and JP-A-2011-128226 can be used. More specifically, the component (F1) may be a polymer having a structural unit (f1) represented by the following general formula (f1-1) (excluding those corresponding to the component (F01)). This polymer is preferably a polymer (homopolymer) consisting only of the structural unit (f1) represented by the following formula (f1-1), a copolymer of the structural unit (f1) and the structural unit (a1), or a copolymer of the structural unit (f1), a structural unit derived from acrylic acid or methacrylic acid, and the structural unit (a1).

[0346] [ka] [In the formula, R is the same as above, and Rf 102 and Rf 103 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; Rf 102 and Rf 103 may be the same or different. 1 is an integer from 0 to 5, and Rf 101 is an organic group containing a fluorine atom.

[0347] In formula (f1-1), R bonded to the carbon atom at the α-position is the same as defined above. R is preferably a hydrogen atom or a methyl group. In formula (f1-1), Rf 102 and Rf 103The halogen atom in Rf is preferably a fluorine atom. 102 and Rf 103 Examples of the alkyl group having 1 to 5 carbon atoms in R include the same alkyl groups having 1 to 5 carbon atoms as those in R, and a methyl group or an ethyl group is preferred. 102 and Rf 103 Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms include groups in which part or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is preferred. Among these, Rf 102 and Rf 103 is preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group. In formula (f1-1), nf 1 represents an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2.

[0348] In formula (f1-1), Rf 101 is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom. The fluorine atom-containing hydrocarbon group may be linear, branched or cyclic and preferably has 1 to 20 carbon atoms, more preferably has 1 to 15 carbon atoms, and particularly preferably has 1 to 10 carbon atoms. Furthermore, in the hydrocarbon group containing fluorine atoms, preferably 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more, and particularly preferably 60% or more are fluorinated, as this enhances the hydrophobicity of the resist film during immersion exposure. Among them, Rf 101 is preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, more preferably a trifluoromethyl group, -CH 2 -CF 3 , -CH 2 -CF 2 -CF 3 , -CH(CF 3 ) 2 , -CH2 -CH 2 -CF 3 , -CH 2 -CH 2 -CF 2 -CF 2 -CF 2 -CF 3 is particularly preferred.

[0349] The weight average molecular weight (Mw) of component (F1) (based on polystyrene conversion by gel permeation chromatography) is preferably 1000 to 50000, more preferably 5000 to 40000, and most preferably 10000 to 30000. When it is below the upper limit of this range, the compound has sufficient solubility in a resist solvent for use as a resist, and when it is above the lower limit of this range, the resist film has good water repellency. The dispersity (Mw / Mn) of the component (F1) is preferably from 1.0 to 5.0, more preferably from 1.0 to 3.0, and most preferably from 1.0 to 2.5.

[0350] In the resist composition of this embodiment, the component (F1) may use either a single type, or a combination of two or more types. When the resist composition contains the component (F1), the content of the component (F1) is preferably 10 mass% or less, more preferably 5 mass% or less, and even more preferably 3 mass% or less, based on the total mass of the component (F). It is particularly preferable that the resist composition of this embodiment does not contain the component (F1). By keeping the content of the component (F1) at or below the preferred upper limit, the effects of the present invention can be more easily obtained.

[0351] <Other ingredients> The resist composition of this embodiment may further contain other components in addition to the above-mentioned components (A), (D), and (F). Examples of other components include the following components (B), (E), and (S).

[0352] <Acid generator component (B)> The resist composition of this embodiment may contain an acid generator component (B) (hereafter referred to as “component (B)”) that generates acid upon exposure. There are no particular limitations on the component (B), and any of the compounds that have been proposed as acid generators for chemically amplified resist compositions can be used. Examples of such acid generators include onium salt-based acid generators such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generators, diazomethane-based acid generators such as bisalkyl or bisarylsulfonyl diazomethanes and poly(bissulfonyl) diazomethanes, nitrobenzylsulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

[0353] Examples of the onium salt-based acid generator include a compound represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), a compound represented by general formula (b-2) (hereinafter also referred to as "component (b-2)"), or a compound represented by general formula (b-3) (hereinafter also referred to as "component (b-3)").

[0354] [ka] [In the formula, R 101 and R 104 ~R 108 R each independently represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. 104 and R 105 R may be bonded to each other to form a ring structure. 102 Y is a fluorine atom or a fluorine-containing alkyl group having 1 to 5 carbon atoms. 101 is a divalent linking group containing an oxygen atom or a single bond. 101 ~V 103 Each of L is independently a single bond, an alkylene group, or a fluorinated alkylene group. 101 ~L 102 Each of L is independently a single bond or an oxygen atom. 103 ~L 105each independently represents a single bond, -CO- or -SO 2 m is an integer of 1 or more, M m+ is an onium cation with a valence of m.

[0355] {anion part} Anion in component (b-1) In formula (b-1), R 101 represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

[0356] Optionally substituted cyclic groups: The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

[0357] R 101 The aromatic hydrocarbon group in the formula (I) is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. R 101 Specific examples of the aromatic ring of the aromatic hydrocarbon group in the above formula include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms, etc. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. R 101Specific examples of the aromatic hydrocarbon group in [description] include a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), and a group in which one of the hydrogen atoms of the aromatic ring is substituted with an alkylene group (for example, arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0358] R 101 The cyclic aliphatic hydrocarbon group in [description] includes an aliphatic hydrocarbon group containing a ring in its structure. Examples of the aliphatic hydrocarbon group containing a ring in this structure include an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, and more preferably 3 to 12. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane, cyclohexane, etc. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, as the polycycloalkane, polycycloalkanes having a crosslinked ring system polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane; polycycloalkanes having a condensed ring system polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferred.

[0359] Among them, R 101The cyclic aliphatic hydrocarbon group in is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, particularly preferably an adamantyl group or a norbornyl group, and most preferably an adamantyl group.

[0360] The linear aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1 to 3. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferred, and specifically, a methylene group [-CH 2 -], ethylene group [-(CH 2 ) 2 -], trimethylene group [-(CH 2 ) 3 -], tetramethylene group [-(CH 2 ) 4 -], pentamethylene group [-(CH 2 ) 5 -] etc. The branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and most preferably 3. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, specifically, -CH(CH 3 )-, -CH(CH 2 CH 3 )-, -C(CH 3 ) 2 -, -C(CH 3 )(CH 2 CH 3 )-, -C(CH 3 )(CH 2 CH 2 CH 3 )-, -C(CH 2 CH 3 ) 2 -, etc. alkylmethylene groups; -CH(CH 3 )CH 2 -, -CH(CH 3 )CH(CH 3 )-, -C(CH3 ) 2 CH 2 -, -CH(CH 2 CH 3 )CH 2 -, -C(CH 2 CH 3 ) 2 -CH 2 -, etc. alkyl ethylene groups; -CH(CH 3 )CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 -, etc.; -CH(CH 3 )CH 2 CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 CH 2 The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0361] Also, R 101 The cyclic hydrocarbon group in may contain a heteroatom, such as a heterocycle. Specifically, the lactone-containing cyclic groups represented by the general formulae (a2-r-1) to (a2-r-7) and the —SO 2 -containing cyclic groups, and heterocyclic groups represented by the above chemical formulas (r-hr-1) to (r-hr-16), respectively. In the above chemical formulas (r-hr-1) to (r-hr-16), * represents Y in formula (b-1). 101 Represents a bond that bonds to .

[0362] R 101 Examples of the substituent in the cyclic group include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group. The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and most preferably a methoxy group or an ethoxy group. Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, with a fluorine atom being preferred. Examples of the halogenated alkyl group as a substituent include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms. The carbonyl group as a substituent is a methylene group (-CH 2 -) is a group that substitutes

[0363] R 101 The cyclic hydrocarbon group in may be a fused ring group containing a fused ring in which an aliphatic hydrocarbon ring and an aromatic ring are fused. Examples of the fused ring include a polycycloalkane having a polycyclic skeleton of a bridged ring system to which one or more aromatic rings are fused. Specific examples of the bridged ring system polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused ring group is preferably a group containing a fused ring in which two or three aromatic rings are fused to a bicycloalkane, and more preferably a group containing a fused ring in which two or three aromatic rings are fused to a bicyclo[2.2.2]octane. 101 Specific examples of the fused cyclic group in the formula (b-1) include those represented by the following formulas (r-br-1) to (r-br-2). 101 Represents a bond that bonds to .

[0364] [ka]

[0365] R 101 Examples of the substituent that the fused cyclic group in the formula (I) may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an aromatic hydrocarbon group, and an alicyclic hydrocarbon group. The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent of the fused ring group are defined as R 101 Examples of the substituents of the cyclic group in the above formula (I) include the same as those exemplified as the substituents of the cyclic group in the above formula (I). Examples of the aromatic hydrocarbon group as the substituent of the fused ring group include a group in which one hydrogen atom has been removed from an aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), a group in which one hydrogen atom of the aromatic ring has been substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.), and the heterocyclic groups represented by the above formulas (r-hr-1) to (r-hr-6). Examples of the alicyclic hydrocarbon group as a substituent of the fused cyclic group include groups obtained by removing one hydrogen atom from a monocycloalkane such as cyclopentane or cyclohexane; groups obtained by removing one hydrogen atom from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane; lactone-containing cyclic groups represented by the general formulae (a2-r-1) to (a2-r-7) above; —SO 2 --containing cyclic group: examples thereof include the heterocyclic groups represented by the above formulae (r-hr-7) to (r-hr-16).

[0366] A chain alkyl group which may have a substituent: R 101 The chain alkyl group may be either linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10. Specific examples include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0367] An optionally substituted chain alkenyl group: R 101 The chain alkenyl group may be either linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, further preferably 2 to 4, and particularly preferably 3. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group. Of the above chain alkenyl groups, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0368] R 101 Examples of the substituent in the chain alkyl or alkenyl group include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and the above-mentioned R 101 Examples of the cyclic groups include the cyclic groups shown in the formula:

[0369] Among the above, R 101 is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, it is preferably a phenyl group, a naphthyl group, or a group in which one or more hydrogen atoms have been removed from a polycycloalkane; a lactone-containing cyclic group represented by each of the general formulae (a2-r-1) to (a2-r-7) above; 2-containing cyclic groups and the like are preferred.

[0370] In formula (b-1), Y 101 is a single bond or a divalent linking group containing an oxygen atom. Y 101 When Y is a divalent linking group containing an oxygen atom, 101 may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms. Examples of divalent linking groups containing an oxygen atom include non-hydrocarbon oxygen atom-containing linking groups such as an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), an oxycarbonyl group (-OC(=O)-), an amide bond (-C(=O)-NH-), a carbonyl group (-C(=O)-), and a carbonate bond (-OC(=O)-O-); combinations of such non-hydrocarbon oxygen atom-containing linking groups with alkylene groups, and the like. These combinations may further include sulfonyl groups (-SO 2 Examples of such a divalent linking group containing an oxygen atom include the linking groups represented by the general formulae (y-al-1) to (y-al-7). In the general formulae (y-al-1) to (y-al-7), R 101 The bond to V' in the general formulae (y-al-1) to (y-al-7) is 101 It is.

[0371] V' 102 The divalent saturated hydrocarbon group in is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

[0372] V' 101 and V' 102 The alkylene group in may be a straight-chain alkylene group or a branched-chain alkylene group, and is preferably a straight-chain alkylene group. V' 101 and V' 102Specific examples of the alkylene group in the formula include a methylene group [-CH 2 -];-CH(CH 3 )-, -CH(CH 2 CH 3 )-, -C(CH 3 ) 2 -, -C(CH 3 )(CH 2 CH 3 )-, -C(CH 3 )(CH 2 CH 2 CH 3 )-, -C(CH 2 CH 3 ) 2 - and other alkylmethylene groups; ethylene groups [-CH 2 CH 2 -];-CH(CH 3 )CH 2 -, -CH(CH 3 )CH(CH 3 )-, -C(CH 3 ) 2 CH 2 -, -CH(CH 2 CH 3 )CH 2 -, etc.; trimethylene group (n-propylene group) [-CH 2 CH 2 CH 2 -];-CH(CH 3 )CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 - and other alkyl trimethylene groups; tetramethylene groups [-CH 2 CH 2 CH 2 CH 2 -];-CH(CH 3 )CH 2 CH 2 CH 2 -, -CH 2 CH(CH 3 )CH 2 CH 2 - and other alkyl tetramethylene groups; pentamethylene groups [-CH 2 CH 2 CH2 CH 2 CH 2 -] etc. Also, V' 101 or V' 102 In the above formula (a1-r-1), some of the methylene groups in the alkylene group may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is represented by Ra' in the above formula (a1-r-1). 3 A divalent group in which one hydrogen atom has been further removed from a cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group, a polycyclic aliphatic hydrocarbon group) such as those mentioned above is preferred, and a cyclohexylene group, a 1,5-adamantylene group or a 2,6-adamantylene group is more preferred.

[0373] Y 101 is preferably a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, and more preferably the linking groups represented by the above formulas (y-al-1) to (y-al-5).

[0374] In formula (b-1), V 101 is a single bond, an alkylene group or a fluorinated alkylene group. 101 The alkylene group and fluorinated alkylene group in the formula (I) preferably have 1 to 4 carbon atoms. 101 The fluorinated alkylene group in 101 In particular, the alkylene group represented by the formula (I) is preferably a group in which some or all of the hydrogen atoms of the alkylene group are substituted with fluorine atoms. 101 is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

[0375] In formula (b-1), R 102 R is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. 102 is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

[0376] Specific examples of the anion moiety represented by the formula (b-1) include, for example, Y 101When Y is a single bond, examples of the anion include a fluorinated alkylsulfonate anion such as a trifluoromethanesulfonate anion or a perfluorobutanesulfonate anion; 101 When is a divalent linking group containing an oxygen atom, examples of the anions include those represented by any of the following formulas (an-1) to (an-3).

[0377] [ka] [In the formula, R” 101 R" is an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group represented by each of the above chemical formulas (r-hr-1) to (r-hr-6), a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), or a chain alkyl group which may have a substituent. 102 represents an aliphatic cyclic group which may have a substituent, a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), a lactone-containing cyclic group represented by each of the above general formulas (a2-r-1), (a2-r-3) to (a2-r-7), or —SO 2 -containing cyclic group. 103 V" is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl group which may have a substituent. 101 R is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Each v" is independently an integer of 0 to 3, each q" is independently an integer of 0 to 20, and n" is 0 or 1.

[0378] R” 101 , R.” 102 and R.” 103 The aliphatic cyclic group which may have a substituent is represented by R 101 As the substituent, R in the formula (b-1) is preferably a group exemplified as the cyclic aliphatic hydrocarbon group. 101Examples of the substituents which may substitute the cyclic aliphatic hydrocarbon group in the above formula (1) include the same as those in the above formula (1).

[0379] R” 103 The aromatic cyclic group which may have a substituent in the formula (b-1) is 101 The substituent is preferably a group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in the formula (b-1). 101 The substituents which may substitute the aromatic hydrocarbon group in the above formula (I) are the same as those in the above formula (I).

[0380] R” 101 The chain alkyl group which may have a substituent in the formula (b-1) is R 101 The alkyl group is preferably one of the groups exemplified as the chain alkyl group in the above formula (I). R” 103 The chain alkenyl group which may have a substituent is represented by R 101 Preferably, it is a group exemplified as the chain alkenyl group in the above formula.

[0381] Anion in component (b-2) In formula (b-2), R 104 , R 105 each independently represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and each represents R 101 However, R 104 , R 105 may be bonded to each other to form a ring. R 104 , R 105 is preferably a chain alkyl group which may have a substituent, and more preferably a linear or branched alkyl group, or a linear or branched fluorinated alkyl group. The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and even more preferably 1 to 3 carbon atoms. 104 , R 105The number of carbon atoms in the chain-like alkyl group of R is preferably as small as possible within the above range of carbon atoms, for reasons such as good solubility in a resist solvent. 104 , R 105 In the chain alkyl group, the more hydrogen atoms substituted with fluorine atoms, the stronger the acid strength becomes, and the more the transparency to high-energy light of 250 nm or less and electron beams improves, which is preferable. The ratio of fluorine atoms in the chain alkyl group, i.e., the fluorination rate, is preferably 70 to 100%, more preferably 90 to 100%, and most preferably a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms. In formula (b-2), V 102 , V 103 each independently represents a single bond, an alkylene group, or a fluorinated alkylene group, and each represents V in formula (b-1). 101 The same can be mentioned. In formula (b-2), L 101 , L 102 are each independently a single bond or an oxygen atom.

[0382] Anion in component (b-3) In formula (b-3), R 106 ~R 108 each independently represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and each represents R 101 The same can be mentioned. In formula (b-3), L 103 ~L 105 each independently represents a single bond, -CO- or -SO 2 -It is.

[0383] Among the above, the anion moiety of the (B) component is preferably the anion in the (b-1) component, more preferably the anion represented by any one of the above general formulae (an-1) to (an-3), further preferably the anion represented by any one of the general formulae (an-1) or (an-2), and particularly preferably the anion represented by the general formula (an-2).

[0384] {cationic part} In the formula (b-1), formula (b-2), and formula (b-3), M m+ represents an onium cation having a valence of m. Among these, a sulfonium cation and an iodonium cation are preferred. m is an integer of 1 or greater.

[0385] Preferred cationic moieties ((M m+ ) 1 / m Examples of the organic cations represented by the formulas (ca-1) to (ca-5) above are given as examples. Among these, the cationic portion ((M m+ ) 1 / m ) is preferably a cation represented by general formula (ca-1).

[0386] In the resist composition of this embodiment, the component (B) may use either a single type, or a combination of two or more types. When the resist composition contains the component (B), the amount of the component (B) in the resist composition is preferably less than 50 parts by mass, more preferably 1 to 40 parts by mass, and even more preferably 3 to 25 parts by mass, per 100 parts by mass of the component (A). By setting the content of the component (B) within the above-mentioned preferred range, sufficient pattern formation can be achieved. Furthermore, when each component of the resist composition is dissolved in an organic solvent, a homogeneous solution is easily obtained, and the storage stability of the resist composition is also favorable.

[0387] <At least one compound (E) selected from the group consisting of organic carboxylic acids, phosphorus oxoacids and derivatives thereof> The resist composition of this embodiment may contain, as an optional component, at least one compound (E) selected from the group consisting of organic carboxylic acids, and phosphorus oxoacids and derivatives thereof (hereafter referred to as "component (E)") for the purposes of preventing deterioration of sensitivity and improving the resist pattern shape and stability over time after exposure. Suitable organic carboxylic acids include, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid. Examples of phosphorus oxoacids include phosphoric acid, phosphonic acid, and phosphinic acid, with phosphonic acid being particularly preferred. Examples of derivatives of phosphorus oxoacids include esters in which the hydrogen atoms of the above oxoacids are substituted with hydrocarbon groups. Examples of the hydrocarbon groups include alkyl groups having 1 to 5 carbon atoms and aryl groups having 6 to 15 carbon atoms. Examples of the derivatives of phosphoric acid include phosphoric acid esters such as di-n-butyl phosphoric acid ester and diphenyl phosphoric acid ester. Examples of the derivatives of phosphonic acid include phosphonic acid esters such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, and dibenzyl phosphonate. Derivatives of phosphinic acid include phosphinic acid esters and phenylphosphinic acid. In the resist composition of this embodiment, the component (E) may use either a single type, or a combination of two or more types. When the resist composition contains the component (E), the amount of the component (E) is typically within a range from 0.01 to 5 parts by mass per 100 parts by mass of the component (A1).

[0388] <Organic solvent component (S)> The resist composition of this embodiment can be produced by dissolving the resist materials in an organic solvent component (hereafter referred to as “component (S)”). The component (S) can be any solvent that is capable of dissolving the individual components used to form a homogeneous solution, and any solvent can be appropriately selected from those known in the art as a solvent for chemically amplified resist compositions. Examples of the (S) component include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, and dipropylene glycol monoacetate; and compounds having an ether bond such as monoalkyl ethers, monoethyl ethers, monopropyl ethers, and monobutyl ethers of the above-mentioned polyhydric alcohols or compounds having an ester bond, or monophenyl ethers. derivatives of polyhydric alcohols (among these, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred); cyclic ethers such as dioxane, esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, and mesitylene, and dimethyl sulfoxide (DMSO). In the resist composition of this embodiment, the component (S) may be used alone or as a mixed solvent of two or more kinds. Of these, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

[0389] As the component (S), a mixed solvent of PGMEA and a polar solvent is also preferred. The blending ratio (mass ratio) may be appropriately determined taking into consideration the compatibility between PGMEA and the polar solvent, and is preferably within the range of 1:9 to 9:1, and more preferably 2:8 to 8:2. More specifically, when EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA:EL or cyclohexanone is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. When PGME is blended as the polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, and even more preferably 3:7 to 7:3. Furthermore, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferable. In addition, as the (S) component, a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mixing ratio is preferably such that the mass ratio of the former to the latter is 70:30 to 95:5. The usage amount of the (S) component is not particularly limited and is appropriately set according to the coating film thickness at a concentration that can be applied to a substrate or the like. Generally, the (S) component is used so that the solid content concentration of the resist composition is in the range of 0.1 to 20% by mass, preferably 0.2 to 15% by mass.

[0390] In the resist composition of this embodiment, additives having miscibility as desired, such as additional resins for improving the performance of the resist film, dissolution inhibitors, plasticizers, stabilizers, colorants, anti-halation agents, dyes, etc., can be appropriately added and contained.

[0391] After dissolving the above resist material in the (S) component, the resist composition of this embodiment may be subjected to removal of impurities or the like using a polyimide porous membrane, a polyamideimide porous membrane, or the like. For example, filtration of the resist composition may be performed using a filter made of a polyimide porous membrane, a filter made of a polyamideimide porous membrane, a filter made of a polyimide porous membrane and a polyamideimide porous membrane, or the like. Examples of the polyimide porous membrane and the polyamideimide porous membrane include those described in JP-A-2016-155121.

[0392] The resist composition of this embodiment described above contains a (D01) component, a (D02) component, and a (F01) component in addition to the (A) component. By including the component (D01), the diffusion of acid in the unexposed area is appropriately controlled. On the other hand, by including the component (D02), deprotection in the exposed area is promoted. Furthermore, by including the component (F01) having the structural unit (f01) and the structural unit (f02), the solubility of the component (F01) in the developer in the exposed area is improved. Due to these actions, the resist composition of this embodiment can improve both the sensitivity and the LWR.

[0393] (Method of forming resist pattern) A method for forming a resist pattern according to a second aspect of the present invention is a method comprising the steps of forming a resist film on a support using the resist composition according to the first aspect of the present invention, exposing the resist film to light, and developing the exposed resist film to form a resist pattern. One embodiment of the resist pattern forming method is, for example, a resist pattern forming method carried out as follows.

[0394] First, the resist composition of the above-described embodiment is applied onto a support using a spinner or the like, and then baked (post-applied bake (PAB)) at a temperature of, for example, 80 to 150° C. for 40 to 120 seconds, preferably 60 to 90 seconds, to form a resist film. Next, the resist film is selectively exposed using an exposure device such as a KrF exposure device, an ArF exposure device, an electron beam lithography device, or an EUV exposure device, either through a mask having a predetermined pattern formed thereon (mask pattern) or by lithography using direct irradiation with an electron beam without using a mask pattern, and then baked (post-exposure bake (PEB)) for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature condition of, for example, 80 to 150°C. Next, the resist film is developed using an alkaline developer in the case of an alkaline development process, or a developer containing an organic solvent (organic developer) in the case of a solvent development process.

[0395] After the development process, a rinse process is preferably carried out. In the case of an alkaline development process, the rinse process is preferably a water rinse using pure water, and in the case of a solvent development process, a rinse liquid containing an organic solvent is preferably used. In the case of a solvent development process, after the development treatment or rinsing treatment, a treatment may be carried out in which the developer or rinsing liquid adhering to the pattern is removed by using a supercritical fluid. After the development treatment or rinsing treatment, drying is performed. In some cases, a baking treatment (post-baking) may be performed after the development treatment. In this manner, a resist pattern can be formed.

[0396] The support is not particularly limited, and may be a conventionally known support, such as a substrate for electronic components or a substrate on which a predetermined wiring pattern is formed. More specifically, it may be a silicon wafer, a substrate made of metal such as copper, chromium, iron, or aluminum, or a glass substrate. As the material for the wiring pattern, for example, copper, aluminum, nickel, or gold may be used. The support may be a substrate as described above on which an inorganic and / or organic film is provided. Examples of inorganic films include inorganic anti-reflective coatings (inorganic BARC). Examples of organic films include organic anti-reflective coatings (organic BARC) and organic films such as lower organic films in a multi-layer resist method. Here, the multilayer resist method is a method in which at least one organic film (lower organic film) and at least one resist film (upper resist film) are provided on a substrate, and the lower organic film is patterned using the resist pattern formed on the upper resist film as a mask, and it is said that a pattern with a high aspect ratio can be formed. That is, according to the multilayer resist method, the required thickness can be secured by the lower organic film, so that the resist film can be made thin, and a fine pattern with a high aspect ratio can be formed. Multilayer resist methods are basically divided into a two-layer structure consisting of an upper resist film and a lower organic film (two-layer resist method), and a three-layer structure consisting of three or more layers with one or more intermediate layers (such as a thin metal film) provided between the upper resist film and the lower organic film (three-layer resist method).

[0397] The wavelength used for exposure is not particularly limited, and may be an ArF excimer laser, a KrF excimer laser, or a F 2 The exposure can be carried out using radiation such as excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. The resist composition is highly useful for KrF excimer laser, ArF excimer laser, EB or EUV, and is more useful for ArF excimer laser. That is, the method of forming a resist pattern of the present embodiment is a particularly useful method when the step of exposing the resist film includes an operation of exposing the resist film to an ArF excimer laser.

[0398] The exposure method for the resist film may be a normal exposure method (dry exposure) performed in air or an inert gas such as nitrogen, or may be liquid immersion lithography. Immersion exposure is an exposure method in which the space between the resist film and the lowest lens of the exposure tool is filled with a solvent (immersion medium) that has a refractive index greater than that of air, and then exposure (immersion exposure) is performed in that state. The immersion medium is preferably a solvent having a refractive index larger than that of air and smaller than that of the resist film to be exposed. The refractive index of the solvent is not particularly limited as long as it is within the above range. Examples of the solvent having a refractive index larger than that of air and smaller than that of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent. Specific examples of fluorine-based inert liquids include C 3 HCl 2 F 5 , C 4 F 9 OCH 3 , C4 F 9 OC 2 H 5 、C 5 H 3 F 7 Examples of the liquid mainly composed of a fluorine compound such as the above include liquids, and those having a boiling point of 70 to 180 ° C are preferred, and those having a boiling point of 80 to 160 ° C are more preferred. When the fluorine-based inert liquid has a boiling point within the above range, after the exposure is completed, the medium used for liquid immersion can be removed by a simple method, which is preferable. As the fluorine-based inert liquid, in particular, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is preferred. Specific examples of the perfluoroalkyl compound include perfluoroalkyl ether compounds and perfluoroalkylamine compounds. Furthermore, specifically, examples of the perfluoroalkyl ether compound include perfluoro(2-butyl-tetrahydrofuran) (boiling point 102 ° C), and examples of the perfluoroalkylamine compound include perfluorotributylamine (boiling point 174 ° C). As the liquid immersion medium, water is preferably used from the viewpoints of cost, safety, environmental issues, versatility, etc.

[0399] Examples of the alkaline developer used for development in the alkaline development process include an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH). The organic solvent contained in the organic developer used for development in the solvent development process may be any one that can dissolve the component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, ether solvents, and hydrocarbon solvents can be mentioned. Ketone-based solvents are organic solvents that contain CC(=O)-C in their structure. Ester-based solvents are organic solvents that contain CC(=O)-OC in their structure. Alcohol-based solvents are organic solvents that contain an alcoholic hydroxyl group in their structure. "Alcoholic hydroxyl group" means a hydroxyl group bonded to a carbon atom of an aliphatic hydrocarbon group. Nitrile-based solvents are organic solvents that contain a nitrile group in their structure. Amide-based solvents are organic solvents that contain an amide group in their structure. Ether-based solvents are organic solvents that contain COC in their structure. Some organic solvents contain multiple types of functional groups that characterize the above-mentioned solvents in their structures, and in such cases, the organic solvent is considered to fall under any of the solvent types that contain the functional groups possessed by the organic solvent. For example, diethylene glycol monomethyl ether is considered to fall under both the alcohol-based solvents and the ether-based solvents in the above classification. The hydrocarbon solvent is a hydrocarbon solvent that is composed of a hydrocarbon that may be halogenated and has no substituents other than halogen atoms. The halogen atom is preferably a fluorine atom. Of the above, the organic solvent contained in the organic developer is preferably a polar solvent, and more preferably a ketone solvent, an ester solvent, a nitrile solvent, or the like.

[0400] Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate, γ-butyrolactone, methyl amyl ketone (2-heptanone), etc. Among these, methyl amyl ketone (2-heptanone) is preferred as the ketone solvent.

[0401] Examples of ester-based solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, methoxyethyl acetate, ethoxyethyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monoethyl ether acetate, 2-ethoxybutyl ... dibutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, proline lactate Examples of the ester-based solvent include pyru, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, etc. Among these, butyl acetate is preferred as the ester-based solvent.

[0402] Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0403] The organic developer may contain known additives as necessary. Examples of such additives include surfactants. The surfactant is not particularly limited, but may be, for example, an ionic or nonionic fluorine-based and / or silicon-based surfactant. The surfactant is preferably a nonionic surfactant, more preferably a nonionic fluorine-based surfactant or a nonionic silicon-based surfactant. When a surfactant is added, the amount added is usually from 0.001 to 5 mass %, preferably from 0.005 to 2 mass %, and more preferably from 0.01 to 0.5 mass %, based on the total amount of the organic developer.

[0404] The development process can be carried out by a known development method, such as a method of immersing the support in a developer for a certain period of time (dip method), a method of piling up the developer on the surface of the support by surface tension and leaving it there for a certain period of time (paddle method), a method of spraying the developer on the surface of the support (spray method), and a method of continuously applying the developer while scanning a developer application nozzle at a constant speed onto a support rotating at a constant speed (dynamic dispense method).

[0405] The organic solvent contained in the rinse solution used in the rinse treatment after the development treatment in the solvent development process can be selected appropriately from the organic solvents listed as the organic solvents used in the organic developer, and can be used if it is difficult to dissolve the resist pattern.Usually, at least one solvent selected from a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent, and an ether solvent is used.Among these, at least one solvent selected from a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, and an amide solvent is preferred, at least one solvent selected from an alcohol solvent and an ester solvent is more preferred, and an alcohol solvent is particularly preferred. The alcohol-based solvent used in the rinse liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be any of linear, branched, and cyclic. Specific examples include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and benzyl alcohol. Among these, 1-hexanol, 2-heptanol, and 2-hexanol are preferred, and 1-hexanol and 2-hexanol are more preferred. These organic solvents may be used alone or in combination of two or more. They may also be used in combination with other organic solvents or water. However, in consideration of development characteristics, the amount of water in the rinse solution is preferably 30% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less, based on the total amount of the rinse solution. The rinse solution may contain known additives as necessary. Examples of such additives include surfactants. The surfactants include those similar to those described above, and nonionic surfactants are preferred, and nonionic fluorine-based surfactants or nonionic silicon-based surfactants are more preferred. When a surfactant is added, the amount of the surfactant added is usually 0.001 to 5 mass %, preferably 0.005 to 2 mass %, and more preferably 0.01 to 0.5 mass %, based on the total amount of the rinse liquid.

[0406] The rinse treatment (cleaning treatment) using a rinse liquid can be carried out by a known rinse method, such as a method of continuously applying the rinse liquid onto a support rotating at a constant speed (spin coating method), a method of immersing the support in the rinse liquid for a certain period of time (dip method), or a method of spraying the rinse liquid onto the surface of the support (spray method).

[0407] According to the method of forming a resist pattern of the present embodiment as described above, the resist composition of the above-mentioned embodiment is used, so that a resist pattern with high sensitivity and reduced roughness can be formed. EXAMPLES

[0408] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0409] <Preparation of Resist Composition> (Examples 1 to 6, Comparative Examples 1 to 8) The components shown in Table 1 were mixed and dissolved to prepare resist compositions of each example.

[0410] [Table 1]

[0411] In Table 1, the abbreviations have the following meanings. The numbers in brackets [ ] indicate the blend amount (parts by mass). (A)-1: Polymer compound represented by the following chemical formula (A-1). The weight average molecular weight (Mw) calculated using standard polystyrene standards by GPC measurement is 7100, and the molecular weight dispersity (Mw / Mn) is 1.63. 13 The copolymer composition ratio (proportion (molar ratio) of each structural unit in the structural formula) determined by C-NMR was l / m / n = 40 / 50 / 10. (A)-2: Polymer compound represented by the following chemical formula (A-2). The weight average molecular weight (Mw) calculated using standard polystyrene standards by GPC measurement is 6,400, and the molecular weight dispersity (Mw / Mn) is 1.59. 13 The copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) determined by C-NMR was l / m = 50 / 50.

[0412] [ka]

[0413] (D01)-1 to (D01)-2: Compounds represented by the following chemical formulas (D01-1) to (D01-2). (D02)-1 to (D02)-3: Compounds represented by the following chemical formulas (D02-1) to (D02-3). (D2)-1: A compound represented by the following chemical formula (D2-1).

[0414] [ka]

[0415] (F01)-1: Polymer compound represented by the following chemical formula (F01-1). The weight average molecular weight (Mw) calculated using standard polystyrene standards by GPC measurement is 26,000, and the molecular weight dispersity (Mw / Mn) is 1.50. 13 The copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) determined by C-NMR was l / m = 80 / 20. (F01)-2: Polymer compound represented by the following chemical formula (F01-2). The weight average molecular weight (Mw) calculated using standard polystyrene standards by GPC measurement is 25,000, and the molecular weight dispersity (Mw / Mn) is 1.50. 13 The copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) determined by C-NMR was l / m = 80 / 20. (F1)-1: Polymer compound represented by the following chemical formula (F1-1). The weight average molecular weight (Mw) calculated using standard polystyrene standards by GPC measurement is 25,000, and the molecular weight dispersity (Mw / Mn) is 1.49. 13 The copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) determined by C-NMR was l / m = 80 / 20. (F1)-2: Polymer compound represented by the following chemical formula (F1-2). The weight average molecular weight (Mw) calculated using standard polystyrene standards by GPC measurement is 27,000, and the molecular weight dispersity (Mw / Mn) is 1.51. 13 The copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) determined by C-NMR was l / m = 80 / 20.

[0416] [ka]

[0417] (B)-1: An acid generator comprising a compound represented by the following chemical formula (B-1).

[0418] [ka]

[0419] (S)-1: a mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether / cyclohexanone = 1200 / 780 / 980 (mass ratio).

[0420] <Formation of Resist Pattern> An organic anti-reflective coating composition "ARC29A" (manufactured by Brewer Science) was applied onto a 12-inch silicon wafer using a spinner, and then baked on a hot plate at 205°C for 60 seconds to dry, forming an organic anti-reflective coating with a thickness of 98 nm. Next, the resist composition of each example was applied onto the organic anti-reflective coating using a spinner, pre-baked (PAB) on a hot plate at 90°C for 60 seconds, and dried to form a resist film with a thickness of 80 nm. After that, a top coat was applied onto the resist film using a spinner, and baked on a hot plate at 90°C for 60 seconds. The resist film was selectively irradiated with an ArF excimer laser (193 nm) through a photomask (6% halftone) using an ArF immersion exposure tool XT1900Gi [ASML; NA (numerical aperture) = 1.35, Dipole, Sigma 0.97-0.78, immersion medium: ultrapure water]. After that, PEB treatment was performed at 95°C for 60 seconds. Next, alkaline development was performed for 10 seconds with a 2.38% by mass TMAH aqueous solution (product name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23° C., followed by rinsing with pure water for 15 seconds and shaking off and drying. As a result, in each example, a line and space pattern (hereinafter referred to as "LS pattern") with a line width of 40 nm and a pitch of 80 nm (mask size 40 nm) was formed.

[0421] [Evaluation of optimal exposure (Eop)] The optimum exposure dose Eop (μC / cm) at which the LS pattern of the target size is formed by the above <Formation of resist pattern> 2 This is called "Eop(μC / cm 2 )" in Table 2.

[0422] [Evaluation of LWR (Line Width Roughness)] The LS pattern formed in the above <Formation of Resist Pattern> was measured for 3σ, which is a measure of LWR. This is shown in Table 2 as "LWR (nm)". "3σ" indicates three times the standard deviation (σ) (unit: nm) obtained from the measurement results of 400 line positions measured in the longitudinal direction of the line using a scanning electron microscope (accelerating voltage 300V, product name: S-9380, manufactured by Hitachi High-Technologies Corporation). The smaller the 3σ value, the smaller the roughness of the line sidewall, meaning that a LS pattern with a more uniform width was obtained.

[0423] [Table 2]

[0424] As shown in Table 2, it was confirmed that the resist compositions of the examples had better sensitivity than the resist compositions of the comparative examples, and were capable of forming resist patterns with better LWR.

Claims

1. A resist composition which generates an acid upon exposure and changes its solubility in a developer by the action of the acid, a base component (A) whose solubility in a developer changes under the action of an acid; an acid generator component (B); An acid diffusion controller component (D) including a compound (D01) represented by the following general formula (d01-1-1) and a compound (D02) represented by the following general formula (d02-1-1), A polymeric compound (F01) having a structural unit (f01) represented by the following general formula (f01-1-1) and a structural unit (f02) represented by the following general formula (f02-1), A resist composition comprising: 【Chemistry 1】 [In the formula, Rd ０１ R is a cyclic group which may have a substituent. ２０１ ~R ２０３ R each independently represents an aryl group, an alkyl group, or an alkenyl group which may have a substituent. ２０１ ~R ２０３ may be bonded to each other to form a ring together with the sulfur atom in the formula. 【Chemistry 2】 [In the formula, Rd ０２ represents a chain alkyl group which may have a substituent. The substituent that the chain alkyl group may have is an aliphatic cyclic group that may have a substituent. The substituent that the aliphatic cyclic group may have is an alkyl group, an alkoxy group, a hydroxyl group, a carbonyl group, a nitro group, an ether bond, an ester bond, or a bond thereof. R ２０１ ~R ２０３ R each independently represents an aryl group, an alkyl group, or an alkenyl group which may have a substituent. ２０１ ~R ２０３ may be bonded to each other to form a ring together with the sulfur atom in the formula. 【Chemistry 3】 [In the formula, each R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; Rf ０１２ and Rf ０１３ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; Rf ０１１ is a fluorinated alkyl group having 1 to 6 carbon atoms; Vf ０２ is a divalent linking group; ０２ is an integer from 0 to 2; Rf ０２ is an acid-dissociable group.

2. 2. The resist composition according to claim 1, wherein a mass ratio of the compound (D01) to the compound (D02) is compound (D01):compound (D02)=1:1 to 5:

1.

3. Rf in general formula (f02-1) ０２ The resist composition according to claim 1 or 2, wherein Rf02-1 is a group represented by the following general formula (Rf02-1): 【Chemistry 4】 [wherein, Rf ０２１ ~Rf ０２３ are each independently a saturated aliphatic hydrocarbon group; R ０２２ and R ０２３ may be bonded to each other to form a ring. * represents a bond bonded to the oxygen atom in formula (f02-1).

4. A method for forming a resist pattern, comprising the steps of: forming a resist film on a support using the resist composition according to any one of claims 1 to 3; exposing the resist film; and developing the exposed resist film to form a resist pattern.

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