Resist composition and resist pattern forming method

Abstract

The present invention relates to a resist composition which generates acid by exposure and whose solubility to a developer is changed by the action of the acid, characterized by containing a base material component (A) whose solubility to a developer is changed by the action of the acid and a polyether compound having a weight average molecular weight of 400 or more, the content of the polyether compound being 0.8 to 32 parts by mass relative to 100 parts by mass of the base material component (A), and the solid content concentration being 25% by mass or more.

Description

TECHNICAL FIELD

[0001] The present application relates to a resist composition and a resist pattern forming method.

[0002] This application claims priority based on Japanese Patent Application No. 2019-155681 filed on August 28, 2019, and the contents thereof are incorporated herein. BACKGROUND

[0003] In the photolithography technique, a process is performed in which, for example, a resist film composed of a resist material is formed on a substrate, the resist film is selectively exposed, and development processing is performed, thereby forming a resist pattern of a prescribed shape in the resist film. A resist material in which the exposed portion of the resist film changes to a property of dissolving in a developer is called a positive type, and a resist material in which the exposed portion of the resist film changes to a property of not dissolving in a developer is called a negative type.

[0004] In recent years, in the production of semiconductor elements and liquid crystal display elements, due to the progress of the photolithography technique, the miniaturization of patterns has rapidly advanced. As a method of miniaturization, generally, the shortening of the wavelength (the increase of the energy) of the exposure light source is performed. Specifically, although ultraviolet rays typified by g-rays and i-rays were used in the past, now, KrF excimer laser or ArF excimer laser is used to perform mass production of semiconductor elements. In addition, research is also being conducted on EUV (extreme ultraviolet rays), EB (electron beams), X-rays, and the like, which have a shorter (higher energy) wavelength than these excimer lasers.

[0005] For a resist material, sensitivity with respect to these exposure light sources, resolution of reproducible fine-sized patterns, and the like are required as lithography characteristics.

[0006] As a resist material satisfying such requirements, a chemically amplified resist composition containing a base material component whose solubility in a developer changes due to the action of an acid, and an acid generator component which generates an acid by exposure has been used in the past.

[0007] For example, in the case where the above-mentioned developer is an alkali developer (alkali development process), as a chemically amplified resist composition of the positive type, a composition containing a resin component (base resin) whose solubility in an alkali developer increases due to the action of an acid, and an acid generator component is generally used. A resist film formed using the resist composition, if selectively exposed at the time of resist pattern formation, an acid is generated from the acid generator component at the exposed portion, the polarity of the base resin increases due to the action of the acid, and the exposed portion of the resist film becomes soluble with respect to the alkali developer. Therefore, by performing alkali development, a non-exposed portion of the resist film remains as a positive pattern.

[0008] On the other hand, when such a chemically amplified resist composition is applied to a solvent development process using a developer containing an organic solvent (organic developer), if the polarity of the matrix resin increases, its solubility in the organic developer relatively decreases. Therefore, the unexposed areas of the resist film are dissolved and removed by the organic developer, forming the exposed areas of the resist film as a negative resist pattern that remains as a pattern. Sometimes, the solvent development process that forms a negative resist pattern in this way is also called a negative development process.

[0009] To date, as the base resin for chemical amplification resist compositions, for example for KrF excimer lasers (248 nm), highly transparent polyhydroxystyrene (PHS) or resins whose hydroxyl groups are protected by acid-dissociative dissolution-inhibiting groups (PHS-type resins) have been used. Or, for example for ArF excimer lasers (193 nm), resins whose hydroxyl groups in the carboxyl groups of (meth)acrylic acid are protected by acid-dissociative dissolution-inhibiting groups ((meth)acrylic acid-type resins) have been used (see, for example, Patent Document 1).

[0010] As the dissolution-inhibiting groups for the acid dissociation, the so-called acetal groups, such as chain ether groups represented by 1-ethoxyethyl or cyclic ether groups represented by tetrahydropyran, tertiary alkyl groups represented by tert-butyl, and tertiary alkyloxycarbonyl groups represented by tert-butyloxycarbonyl are mainly used.

[0011] In addition, a wide variety of acid-generating agents have been proposed to date as acid-generating agents used in chemically amplified resist compositions, including, for example, onium salt acid-generating agents such as iodonium salts or sulfonium salts, sulfonate oxime acid-generating agents, diazomethane acid-generating agents, nitrobenzyl sulfonate acid-generating agents, iminosulfonate acid-generating agents, disulfone acid-generating agents, etc.

[0012] Among these, onium salt-based acid-generating agents are commonly used, primarily those with onium ions such as triphenylsulfonium in the cation portion. In the anionic portion of these onium salt-based acid-generating agents, alkyl sulfonate ions or fluoroalkyl sulfonate ions obtained by replacing some or all of the hydrogen atoms of the alkyl group with fluorine atoms are generally used.

[0013] However, with the increasing integration of LSIs and the high speed of communication, there is a growing demand for larger memory capacities and rapid development in pattern miniaturization. While electron beam or EUV lithography aims to form patterns as fine as tens of nanometers, it still faces numerous limitations in terms of productivity and other technical issues, hindering its application in microfabrication.

[0014] In response, in addition to miniaturization, the development of three-dimensional structure devices that achieve high-capacity memory by stacking cells has been promoted.

[0015] Existing technical documents

[0016] Patent Literature

[0017] Patent Literature 1: Japanese Patent Application Laid-Open (JP A) No. 2003-241385 SUMMARY

[0018] PROBLEMS TO BE SOLVED BY THE INVENTION

[0019] In the production of the three-dimensional structure device, there is a process of forming a thick resist film, for example, a film thickness of 5 μm or more, which is thicker than conventional films, on the surface of a workpiece, forming a resist pattern, and performing etching or the like. In the case where a chemically amplified resist composition is used here, there is a problem that the thicker the film thickness of the resist film, the more difficult it is to maintain the sensitivity at the time of exposure, the resolution at the time of development is reduced, and it is difficult to obtain a desired resist pattern shape. In addition, there is also a problem that the thicker the film thickness of the resist film, the more likely it is to generate cracks in the resist pattern.

[0020] The present application has been achieved in view of the above-described circumstances, and a technical problem thereof is to provide a resist composition capable of forming a thick resist film and less likely to generate cracks, and having a good resolution, and a resist pattern forming method using the same.

[0021] SOLUTION TO THE PROBLEM

[0022] In order to solve the above-described technical problem, the present application adopts the following configuration.

[0023] That is, the first aspect of the present application is a resist composition which generates acid by exposure and whose solubility to a developer changes due to the action of the acid, characterized by containing a base material component (A) whose solubility to a developer changes due to the action of the acid and a polyether compound having a weight average molecular weight of 400 or more, the content of the polyether compound being 0.8 to 32 parts by mass per 100 parts by mass of the base material component (A), and the solid content concentration of the resist composition being 25% by mass or more.

[0024] The second aspect of the present application is a resist pattern forming method characterized by having a process of forming a resist film using the resist composition of the first aspect on a support, a process of exposing the resist film, and a process of developing the exposed resist film to form a resist pattern.

[0025] EFFECT OF THE INVENTION

[0026] According to the present application, it is possible to provide a resist composition capable of forming a thick resist film and less likely to generate cracks, and having a good resolution, and a resist pattern forming method using the same. DETAILED DESCRIPTION

[0027] In the present specification and the present claims, "aliphatic" is a relative concept with respect to aromatic, and is defined as a group, compound, etc. that does not have aromaticity.

[0028] Unless otherwise specified, "alkyl" includes a 1-valent saturated hydrocarbon group of a straight chain, a branched chain, and a cyclic structure. The same applies to the alkyl group in an alkoxy group.

[0029] Unless otherwise specified, "alkylene" includes a 2-valent saturated hydrocarbon group of a straight chain, a branched chain, and a cyclic structure.

[0030] "Alkyl halide" is a group in which some or all of the hydrogen atoms of an alkyl group are substituted with halogen atoms, and as the halogen atoms, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom can be exemplified.

[0031] "Fluoroalkyl" or "fluoroalkylene" refers to a group in which some or all of the hydrogen atoms of an alkyl group or an alkylene group are substituted with fluorine atoms.

[0032] "Structural unit" refers to a monomeric unit (monomer unit) that constitutes a high molecular compound (resin, polymer, copolymer).

[0033] In the case of being described as "may have a substituent" or "may have a substituent", both the case of being substituted with a 1-valent group with respect to a hydrogen atom (-H) and the case of being substituted with a 2-valent group with respect to a methylene group (-CH2-) are included.

[0034] "Exposure" is a concept that includes irradiation of all types of radiation.

[0035] "Base component" refers to an organic compound having a film forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. By making the molecular weight of the organic compound 500 or more, the film forming ability is improved, and in addition, a nanoscale resist pattern is easily formed. The organic compound used as the base component is roughly classified into a non-polymer and a polymer. As the non-polymer, a non-polymer having a molecular weight of 500 or more and less than 4000 is generally used. Hereinafter, in the case of referring to a "low molecular compound", a non-polymer having a molecular weight of 500 or more and less than 4000 is meant. As the polymer, a polymer having a molecular weight of 1000 or more is generally used. Hereinafter, in the case of referring to a "resin", a "high molecular compound", or a "polymer", a polymer having a molecular weight of 1000 or more is meant. As the molecular weight of the polymer, a weight average molecular weight based on polystyrene conversion by GPC (gel permeation chromatography) is used.

[0036] "Structural unit derived from an acrylate" refers to a structural unit constituted by cleavage of the ethylenic double bond of an acrylate.

[0037] "Acrylate" is a compound in which the hydrogen atom at the carboxyl end of acrylic acid (CH2=CH-COOH) is substituted with an organic group.

[0038] The hydrogen atom bonded to the carbon atom at the α-position of the acrylate can be substituted with a substituent. The substituent (R α0 ) that substitutes the hydrogen atom bonded to the carbon atom at the α-position is an atom or group other than a hydrogen atom, and examples include an alkyl group having a carbon number of 1 to 5, a haloalkyl group having a carbon number of 1 to 5, and the like. In addition, it also includes itaconic acid diester in which the substituent (R α0 ) is substituted with a substituent containing an ester bond, α-hydroxy acrylate in which the substituent (R α0 ) is substituted with a hydroxyalkyl group or a group that modifies the hydroxy group thereof. In addition, unless otherwise specified, the carbon atom at the α-position of the acrylate refers to the carbon atom bonded to the carbonyl group of the acrylic acid.

[0039] Hereinafter, the acrylate in which the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent will be sometimes referred to as α-substituted acrylate. In addition, the acrylate and the α-substituted acrylate will be sometimes collectively referred to as "(α-substituted) acrylate".

[0040] "Structural unit derived from hydroxystyrene" refers to a structural unit formed by cleavage of the olefinic double bond of hydroxystyrene. "Structural unit derived from hydroxystyrene derivative" refers to a structural unit formed by cleavage of the olefinic double bond of hydroxystyrene derivative.

[0041] "Hydroxystyrene derivative" refers to a concept including a compound in which the hydrogen atom at the α-position of hydroxystyrene is substituted with another substituent such as an alkyl group, a haloalkyl group, and the like, and derivatives thereof. As the derivatives thereof, examples include a compound in which the hydrogen atom of the hydroxyl group of hydroxystyrene is substituted with an organic group, a compound in which a substituent other than a hydroxyl group is bonded to the benzene ring of hydroxystyrene in which the hydrogen atom at the α-position can be substituted with a substituent, and the like. In addition, unless otherwise specified, the α-position (carbon atom at the α-position) refers to the carbon atom bonded to the benzene ring.

[0042] As the substituent that substitutes the hydrogen atom at the α-position of the substituted hydroxystyrene, the same groups as those exemplified as the substituent at the α-position in the α-substituted acrylate can be exemplified.

[0043] "Structural unit derived from vinylbenzoic acid or vinylbenzoic acid derivative" refers to a structural unit formed by cleavage of the olefinic double bond of vinylbenzoic acid or vinylbenzoic acid derivative.

[0044] The "vinylbenzoic acid derivative" is a concept including a compound in which the hydrogen atom at the α-position of vinylbenzoic acid is substituted with an alkyl group, a halogenated alkyl group, or another substituent, and derivatives thereof. As the derivatives thereof, a compound in which the hydrogen atom at the α-position is substituted with a substituent, a compound in which the hydrogen atom of the carboxyl group of vinylbenzoic acid is substituted with an organic group, a compound in which a substituent other than a hydroxyl group and a carboxyl group is bonded to the benzene ring of vinylbenzoic acid in which the hydrogen atom at the α-position is substituted with a substituent, and the like can be exemplified. In addition, unless otherwise specified, the α-position (carbon atom at the α-position) refers to the carbon atom to which the benzene ring is bonded.

[0045] The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, and specifically, an alkyl group having a carbon number of 1 to 5 (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, pentyl group, isopentyl group, neopentyl group), and the like can be exemplified.

[0046] In addition, the halogenated alkyl group as the substituent at the α-position can specifically exemplify a group in which a part or all of the hydrogen atoms of the "alkyl group as the substituent at the α-position" described above are substituted with a halogen atom. As the halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like can be exemplified, and a fluorine atom is particularly preferred.

[0047] In addition, the hydroxyalkyl group as the substituent at the α-position can specifically exemplify a group in which a part or all of the hydrogen atoms of the "alkyl group as the substituent at the α-position" described above are substituted with a hydroxyl group. The number of the hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.

[0048] In the present specification and the present claims, depending on the structure represented by the chemical formula, there is a structure of an asymmetric carbon, and a structure of an enantiomer or a diastereomer can exist. In this case, one chemical formula represents these isomers typically. These isomers can be used individually, or can be used as a mixture.

[0049] (Resist composition)

[0050] The resist composition of the first aspect of the present application is a resist composition in which the solubility to a developer is changed by acid generated by exposure and the action of acid, and contains a base material component (A) in which the solubility to a developer is changed by acid (hereinafter also referred to as "(A) component"), and a polyether compound having a weight average molecular weight of 400 or more (hereinafter also referred to as "(Z) component"). In the resist composition of the present embodiment, the content of the (Z) component is 0.8 to 32 parts by mass with respect to 100 parts by mass of the (A) component. In addition, the solid content concentration of the resist composition of the present embodiment is 25% by mass or more.

[0051] If the above-described resist composition is used to form a resist film, a thick resist film (for example, a film thickness of 5 μm or more) can be formed.

[0052] If the above-described resist composition is used to form a resist film, and the resist film is subjected to selective exposure, acid is generated in the exposed portion of the resist film, the solubility of the (A) component to a developer is changed by the action of the acid, on the other hand, in the unexposed portion of the resist film, the solubility of the (A) component to a developer does not change, and thus a difference in solubility to a developer is generated between the exposed portion and the unexposed portion of the resist film. Therefore, if the resist film is developed, in the case where the resist composition is a positive type, the exposed portion of the resist film is dissolved and removed, and thus a positive resist pattern is formed, in the case where the resist composition is a negative type, the unexposed portion of the resist film is dissolved and removed, and thus a negative resist pattern is formed.

[0053] In the present specification, a resist composition in which the exposed portion of a resist film is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition in which the unexposed portion of a resist film is dissolved and removed to form a negative resist pattern is referred to as a negative resist composition. The resist composition of the present embodiment can be either a positive resist composition or a negative resist composition. In addition, the resist composition of the present embodiment can be applied to an alkali developing process in which an alkali developer is used in a developing treatment at the time of resist pattern formation, or can be applied to a solvent developing process in which a developer containing an organic solvent (organic developer) is used in the developing treatment.

[0054] The resist composition of the present embodiment has an acid-generating ability by which acid is generated by exposure, and can be either a (A) component that generates acid by exposure or an additive component that is mixed separately from the (A) component and generates acid by exposure.

[0055] Specifically, the resist composition (1) of the present embodiment can further contain an acid generator component (B) that generates an acid by exposure (hereinafter referred to as "(B) component"); (2) can be a case where the (A) component is a component that generates an acid by exposure; (3) can be a case where the (A) component is a component that generates an acid by exposure and further contains the (B) component. That is, in the cases of (2) and (3) above, the (A) component is a "base material component that generates an acid by exposure and whose solubility in a developer changes due to the action of the acid". In the case where the (A) component is a base material component that generates an acid by exposure and whose solubility in a developer changes due to the action of the acid, the (Al) component described later is preferably a high molecular compound that generates an acid by exposure and whose solubility in a developer changes due to the action of the acid. As such a high molecular compound, a resin having a structural unit that generates an acid by exposure can be used. As the structural unit that generates an acid by exposure, a publicly known structural unit can be used. Among them, the resist composition of the present embodiment is preferably the case of (1) above.

[0056] <(A) component>

[0057] In the resist composition of the present embodiment, the (A) component preferably contains a resin component (Al) whose solubility in a developer changes due to the action of an acid (hereinafter also referred to as "(Al) component"). By using the (Al) component, since the polarity of the base material component changes before and after exposure, a good developing contrast can be obtained not only in an alkaline developing process but also in a solvent developing process.

[0058] As the (A) component, at least the (Al) component is used, and other high molecular compounds and / or low molecular compounds can be used together with the (Al) component.

[0059] In the case of applying an alkaline developing process, the base material component containing the (Al) component is insoluble in an alkaline developer before exposure, and, for example, if an acid is generated from the (B) component by exposure, the polarity thereof increases due to the action of the acid, and thus the solubility in the alkaline developer increases. Therefore, in the formation of a resist pattern, if a resist film obtained by applying the resist composition on a support is selectively exposed, the solubility of the exposed part of the resist film in the alkaline developer changes from insolubility to solubility, and on the other hand, since the unexposed part of the resist film remains alkali-insoluble and does not change, a positive resist pattern can be formed by performing an alkaline development.

[0060] On the other hand, in the case of applying a solvent developing process, the base component containing the (Al) component has high solubility to an organic developing solution before exposure, and, for example, if an acid is generated from the (B) component by exposure, the polarity thereof becomes high due to the action of the acid, and the solubility to the organic developing solution decreases. Therefore, in the formation of a resist pattern, if exposure is selectively performed on a resist film obtained by applying the resist composition on a support, the solubility of the exposed part of the resist film to the organic developing solution changes from soluble to insoluble, on the other hand, since the unexposed part of the resist film remains soluble and does not change, by developing using the organic developing solution, it is possible to produce contrast between the exposed part and the unexposed part, thereby forming a negative resist pattern.

[0061] In the resist composition of the present embodiment, the (A) component can be used alone in one kind, or two or more kinds can be used in combination.

[0062] • Regarding the (Al) component

[0063] The (Al) component is a resin component whose solubility to a developing solution changes due to the action of an acid. As the (Al) component, it is preferable to have a structural unit (al) containing an acid-decomposable group whose polarity increases due to the action of an acid.

[0064] The (Al) component can have other structural units in addition to the structural unit (al) as necessary.

[0065] Structural unit (al)

[0066] The structural unit (al) is a structural unit containing an acid-decomposable group whose polarity increases due to the action of an acid.

[0067] The "acid-decomposable group" is a group having acid-decomposability, which is the ability of at least a part of the bond in the structure of the acid-decomposable group to cleave under the action of an acid.

[0068] As the acid-decomposable group whose polarity increases due to the action of an acid, for example, a group that generates a polar group by the action of an acid can be exemplified.

[0069] As the polar group, for example, a carboxyl group, a hydroxyl group, an amino group, a sulfonic acid group (-SO3H), and the like can be exemplified. Among these, it is preferable to be a polar group containing -OH in the structure (hereinafter also referred to as "polar group containing OH"), more preferable to be a carboxyl group or a hydroxyl group, and particularly preferable to be a carboxyl group.

[0070] As the acid-decomposable group, more specifically, a group in which the polar group is protected by an acid dissociation group (for example, a group in which the hydrogen atom of the polar group containing OH is protected by an acid dissociation group) can be exemplified.

[0071] Herein, the "acid dissociable group" means either (i) a group having an acid dissociability that the bond between the acid dissociable group and the atom adjacent to the acid dissociable group can be cleaved by the action of an acid; or (ii) a group that, after a part of the bond is cleaved by the action of an acid, further generates a decarboxylation reaction, whereby the bond between the acid dissociable group and the atom adjacent to the acid dissociable group can be cleaved.

[0072] The acid dissociable group constituting the acid-decomposable group must be a group having a polarity lower than that of the polar group generated by the dissociation of the acid dissociable group, whereby, upon dissociation of the acid dissociable group by the action of an acid, a polar group having a higher polarity than that of the acid dissociable group is generated, and thus the polarity increases. As a result, the polarity of the (Al) component as a whole increases. By the increase in the polarity, the solubility to the developer changes relatively, and in the case where the developer is an alkali developer, the solubility increases, and in the case where the developer is an organic developer, the solubility decreases.

[0073] As the acid dissociable group, groups proposed so far as the acid dissociable group of the base resin for the chemically amplified resist composition can be exemplified.

[0074] As the acid dissociable group of the base resin for the chemically amplified resist composition, specifically, the "acetal type acid dissociable group", "tertiary alkyl ester type acid dissociable group", and "tertiary alkoxy carbonyl acid dissociable group" described below can be exemplified.

[0075] Acetal type acid dissociable group:

[0076] As the acid dissociable group for protecting the carboxyl group or the hydroxyl group in the polar group, for example, the acid dissociable group represented by the following general formula (al-r-l) (hereinafter also referred to as "acetal type acid dissociable group") can be exemplified.

[0077] [Chemical Formula 1]

[0078]

[0079] [In the formula, Ra 1 , Ra 2 is a hydrogen atom or an alkyl group. Ra 3 is a hydrocarbon group, Ra 3 may be bonded to any one of Ra 1 , Ra 2 to form a ring.]

[0080] In the formula (al-r-l), it is preferable that at least one of Ra 1 and Ra 2 be a hydrogen atom, and more preferable that both be hydrogen atoms.

[0081] In the case where Ra' 1 or Ra' 2 is an alkyl group, as the alkyl group, the same alkyl groups as those exemplified above as the substituent which can be bonded to the carbon atom at the α-position of the α-substituted acrylic acid ester can be exemplified, and an alkyl group having 1 to 5 carbon atoms is preferred. Specifically, a linear or branched alkyl group can be preferably exemplified. More specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a t-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and the like can be exemplified, and a methyl group or an ethyl group is more preferred, and a methyl group is particularly preferred.

[0082] In the formula (al-r-l), as the hydrocarbon group of Ra' 3 , a linear or branched alkyl group, or a cyclic hydrocarbon group can be exemplified.

[0083] The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and further preferably 1 or 2 carbon atoms. Specifically, a methyl group, an ethyl group, a n-propyl group, a n-butyl group, a n-pentyl group, and the like can be exemplified. Among them, a methyl group, an ethyl group, or a n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

[0084] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, an isopropyl group, an isobutyl group, a t-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, a 2,2-dimethylbutyl group, and the like can be exemplified, and an isopropyl group is preferred.

[0085] In the case where Ra' 3 is a cyclic hydrocarbon group, the hydrocarbon group can be an aliphatic hydrocarbon group, or an aromatic hydrocarbon group, and in addition, can be a polycyclic group, or a monocyclic group.

[0086] As the aliphatic hydrocarbon group of the monocyclic group, a group obtained by removing one hydrogen atom from a monocyclic alkane is preferred. As the monocyclic alkane, a monocyclic alkane having 3 to 6 carbon atoms is preferred, and specifically, a cyclopentane, a cyclohexane, and the like can be exemplified.

[0087] As the aliphatic hydrocarbon group of the polycyclic group, a group obtained by removing one hydrogen atom from a polycyclic alkane is preferred, and as the polycyclic alkane, a polycyclic alkane having 7 to 12 carbon atoms is preferred, and specifically, an adamantane, a norbornane, an isobornane, a tricyclodecane, a tetracyclododecane, and the like can be exemplified.

[0088] In the case where the cyclic hydrocarbon group of Ra' 3 is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

[0089] The aromatic ring, if it is a cyclic conjugated system having 4n + 2 π electrons, is not particularly limited and can be monocyclic or polycyclic. The number of carbons of the aromatic ring is preferably 5 to 30, more preferably 5 to 20, further preferably 6 to 15, and particularly preferably 6 to 12.

[0090] As the aromatic ring, specifically, there can be mentioned an aromatic hydrocarbon ring such as benzene, naphthalene, anthracene, phenanthrene, and the like; an aromatic heterocycle in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom; and the like. As the hetero atom in the aromatic heterocycle, there can be mentioned an oxygen atom, a sulfur atom, a nitrogen atom, and the like. As the aromatic heterocycle, specifically, there can be mentioned a pyridine ring, a thiophene ring, and the like.

[0091] As Ra' 3 , specifically, there can be mentioned a group (an aryl group or a heteroaryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocycle; a group obtained by removing one hydrogen atom from an aromatic compound (for example, biphenyl, fluorene, and the like) containing two or more aromatic rings; a group (for example, an aralkyl 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, and the like) obtained by substituting one hydrogen atom of the aromatic hydrocarbon ring or the aromatic heterocycle with an alkylene group; and the like. The number of carbons of the alkylene group bonded to the aromatic hydrocarbon ring or the aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0092] Ra' 3 in the formula can have a substituent. As the substituent, for example, there can be mentioned -R P1 , -R P2 -O-R P1 , -R P2 -CO-R P1 , -R P2 -CO-OR P1 , -R P2 -O-CO-R P1 , -R P2 -OH, -R P2 -CN, or -R P2 -COOH (hereinafter, these substituents will be collectively referred to as "Ra 05 " and the like).

[0093] Here, R P1 is a monovalent chain saturated hydrocarbon group having a carbon number of 1 to 10, a monovalent aliphatic cyclic saturated hydrocarbon group having a carbon number of 3 to 20, or a monovalent aromatic hydrocarbon group having a carbon number of 6 to 30. Furthermore, R P2 is a single bond, a divalent chain saturated hydrocarbon group having a carbon number of 1 to 10, a divalent aliphatic cyclic saturated hydrocarbon group having a carbon number of 3 to 20, or a divalent aromatic hydrocarbon group having a carbon number of 6 to 30. Among them, RP1 and R P2 Some or all of the hydrogen atoms in the chain saturated hydrocarbon group, the aliphatic cyclic saturated hydrocarbon group, and the aromatic hydrocarbon group can be substituted with fluorine atoms. The aliphatic cyclic hydrocarbon group can have one of the above-mentioned substituents alone, or a plurality of the above-mentioned substituents each of which is one or more.

[0094] As the monovalent chain saturated hydrocarbon group having a carbon number of 1 to 10, for example, there can be mentioned methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, and the like.

[0095] As the monovalent aliphatic cyclic saturated hydrocarbon group having a carbon number of 3 to 20, for example, there can be mentioned monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, cyclododecyl group, and the like; polycyclic aliphatic saturated hydrocarbon groups such as bicyclo[2.2.2]octyl group, tricyclo[5.2.1.02,6]decyl group, tricyclo[3.3.1.13,7]decyl group, tetracyclo[6.2.1.13,6.02,7]dodecyl group, adamantyl group, and the like.

[0096] As the monovalent aromatic hydrocarbon group having a carbon number of 6 to 30, for example, there can be mentioned groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene, and the like.

[0097] In the case where any one of Ra 3 and Ra 1 , and Ra 2 is bonded to form a ring, as the ring group, a four- to seven-membered ring is preferred, and a four- to six-membered ring is more preferred. As specific examples of the ring group, there can be mentioned tetrahydropyranyl group, tetrahydrofuranyl group, and the like.

[0098] Tertiary alkyl ester type acid dissociation group:

[0099] As the acid dissociation group for protecting the carboxyl group in the above-mentioned polar group, for example, there can be mentioned acid dissociation groups represented by the following general formula (al-r-2).

[0100] Further, for the purpose of explanation, the group composed of an alkyl group in the acid dissociation group represented by the following formula (al-r-2) will also be referred to as "tertiary alkyl ester type acid dissociation group" hereinafter.

[0101] [Chemical Formula 2]

[0102]

[0103] [In the formula, Ra 4 to Ra 6 are each a hydrocarbon group, and Ra 5 , Ra 6 may be bonded to each other to form a ring.]

[0104] As the hydrocarbon group of Ra 4 , a linear or branched alkyl group, a chain or cyclic alkenyl group, or a cyclic hydrocarbon group can be exemplified.

[0105] Ra 4 in the linear or branched alkyl group, the cyclic hydrocarbon group (aliphatic hydrocarbon group as monocyclic group, aliphatic hydrocarbon group as polycyclic group, aromatic hydrocarbon group) can be exemplified the same group as the Ra 3 .

[0106] As the chain or cyclic alkenyl group of Ra 4 , an alkenyl group having 2 to 10 carbons is preferable.

[0107] As the hydrocarbon group of Ra 5 , Ra 6 , the same hydrocarbon group as the above Ra 3 can be exemplified.

[0108] In the case where Ra 5 and Ra 6 are bonded to each other to form a ring, the following group represented by the general formula (al-r2-1), the following group represented by the general formula (al-r2-2), the following group represented by the general formula (al-r2-3) can be preferably exemplified.

[0109] On the other hand, in the case where Ra 4 to Ra 6 are not bonded to each other to be independent hydrocarbon groups, the following group represented by the general formula (al-r2-4) can be preferably exemplified.

[0110] [Chemical Formula 3]

[0111]

[0112] [In the formula (al-r2-1), Ra 10 represents an alkyl group having 1 to 10 carbons or a group represented by the general formula (al-r2-r1). Ra 11 represents a group which forms an aliphatic cyclic group together with the carbon atom to which Ra 10 is bonded. In the formula (al-r2-2), Ya is a carbon atom. Xa is a group which forms a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of the cyclic hydrocarbon group can be substituted. Ra 01 to Ra 03each independently is a hydrogen atom, a monovalent chain saturated hydrocarbon group having a carbon number of 1 to 10, or a monovalent aliphatic cyclic saturated hydrocarbon group having a carbon number of 3 to 20. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group can be substituted. Ra 01 ~ Ra 03 Two or more of the above formulae (a1-r2-1) can be bonded to each other to form a ring structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group that forms an aliphatic cyclic group together with Yaa. Ra 04 is an aromatic hydrocarbon group that can have a substituent. In formula (a1-r2-4), Ra 12 and Ra 13 each independently is a monovalent chain saturated hydrocarbon group having a carbon number of 1 to 10, or a hydrogen atom. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group can be substituted. Ra 14 is a hydrocarbon group that can have a substituent. * indicates a bond.

[0113] [Chemical Formula 4]

[0114]

[0115] [In the formula, Ya 0 is a quaternary carbon atom. Ra 031 , Ra 032 , and Ra 033 each independently is a hydrocarbon group that can have a substituent. Among them, one or more of Ra 031 , Ra 032 , and Ra 033 is a hydrocarbon group having at least one polar group.

[0116] In the above formula (a1-r2-1), Ra 10 is an alkyl group having a carbon number of 1 to 10. The alkyl group having a carbon number of 1 to 10 is preferably a straight-chain or branched-chain alkyl group exemplified as Ra 3 in the above formula (a1-r-1). Ra 10 is preferably an alkyl group having a carbon number of 1 to 5.

[0117] In the above formula (a1-r2-r1), Ya 0 is a quaternary carbon atom. That is, the adjacent carbon atoms bonded to Ya 0 (carbon atom) are four.

[0118] In the above formula (a1-r2-r1), Ra 031 , Ra 032 , and Ra 033 each independently is a hydrocarbon group that can have a substituent. As Ra 031 , Ra 032 , and Ra 033The hydrocarbon groups in the text can be exemplified independently as straight-chain or branched alkyl groups, chain or cyclic alkenyl groups, or cyclic hydrocarbon groups.

[0119] Ra 031 Ra 032 and Ra 033 The linear alkyl group in the form preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and even more preferably 1 or 2. Specifically, examples include methyl, ethyl, n-propyl, n-butyl, and n-pentyl. Among these, methyl, ethyl, or n-butyl is preferred, and methyl or ethyl is more preferred.

[0120] Ra 031 Ra 032 and Ra 033 The branched alkyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5. Specifically, examples include isopropyl, isobutyl, tert-butyl, isopentyl, neopentyl, 1,1-diethylpropyl, 2,2-dimethylbutyl, etc., with isopropyl being the most preferred.

[0121] Ra 031 Ra 032 and Ra 033 The chain or cyclic alkenyl group is preferably an alkenyl group with 2 to 10 carbon atoms.

[0122] In Ra 031 Ra 032 and Ra 033 The cyclic hydrocarbon group in it can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. In addition, it can be a polycyclic group or a monocyclic group.

[0123] The aliphatic hydrocarbon group that is a monocyclic group is preferably a group obtained by removing one hydrogen atom from a monocyclic alkane. The monocyclic alkane is preferably a monocyclic alkane with 3 to 6 carbon atoms; examples include cyclopentane and cyclohexane.

[0124] The aliphatic hydrocarbon group that is the polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycyclic alkane. The polycyclic alkane is preferably a polycyclic alkane with 7 to 12 carbon atoms. Examples of such polycyclic alkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0125] Ra 031 Ra 032 and Ra 033The aromatic hydrocarbon group in the above-mentioned Ra, Rb, and Rc 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 can be monocyclic or polycyclic. The number of carbons of the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, further preferably from 6 to 15, and particularly preferably from 6 to 12. As the aromatic ring, specifically, aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom can be exemplified. As the hetero atom in the aromatic heterocyclic ring, oxygen atom, sulfur atom, nitrogen atom, and the like can be exemplified. As the aromatic heterocyclic ring, specifically, pyridine ring, thiophene ring, and the like can be exemplified. As the aromatic hydrocarbon group, specifically, groups (aryl group or heteroaryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocyclic ring; groups obtained by removing one hydrogen atom from an aromatic compound (for example, biphenyl, fluorene, and the like) having two or more aromatic rings; groups (for example, aralkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, and the like) in which one hydrogen atom of the aromatic hydrocarbon ring or the aromatic heterocyclic ring is substituted with an alkylene group; and the like can be exemplified. The number of carbons of the alkylene group bonded to the aromatic hydrocarbon ring or the aromatic heterocyclic ring is preferably from 1 to 4, more preferably from 1 to 2, and particularly preferably 1.

[0126] The above-mentioned hydrocarbon group represented by Ra 031 , Rb 032 , and Rc 033 may be substituted. As the substituent, for example, hydroxyl group, carboxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, and the like), alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, and the like), alkoxycarbonyl group, and the like can be exemplified.

[0127] Among the above-mentioned, the hydrocarbon group represented by Ra 031 , Rb 032 , and Rc 033 may have a substituent. The hydrocarbon group having a substituent is preferably a linear or branched alkyl group having a substituent, and more preferably a linear alkyl group having a substituent.

[0128] Among the above-mentioned, one or more of the hydrocarbon groups represented by Ra 031 , Rb 032 , and Rc 033 are a hydrocarbon group having a polar group.

[0129] The "hydrocarbon group having a polar group" means a hydrocarbon group in which a methylene group (-CH2-) constituting the hydrocarbon group is substituted with a polar group or a hydrocarbon group in which at least one hydrogen atom constituting the hydrocarbon group is substituted with a polar group.

[0130] As the "hydrocarbon group having a polar group", a functional group represented by the following general formula (al-pl) is preferable.

[0131] [Chemical Formula 5]

[0132]

[0133] (In the formula, Ra 07 represents a divalent hydrocarbon group having a carbon number of 2 to 12. Ra 08 represents a divalent linking group containing a hetero atom. Ra 06 represents a monovalent hydrocarbon group having a carbon number of 1 to 12. n p0 is an integer of 1 to 6.

[0134] In the formula (a1-p1), Ra 07 represents a divalent hydrocarbon group having a carbon number of 2 to 12. Ra 07 having a carbon number of 2 to 12, preferably 2 to 8, more preferably 2 to 6, further preferably 2 to 4, and particularly preferably 2.

[0135] Ra 07 The hydrocarbon group in Ra

[0136] As Ra 07 , for example, the following can be exemplified: a linear alkanediyl group such as ethene-1, 3-diyl, butane-1, 4-diyl, pentane-1, 5-diyl, hexane-1, 6-diyl, heptane-1, 7-diyl, octane-1, 8-diyl, nonane-1, 9-diyl, decane-1, 10-diyl, undecane-1, 11-diyl, dodecane-1, 12-diyl, and the like; a branched alkanediyl group such as propane-1, 2-diyl, 1-methylbutane-1, 3-diyl, 2-methylpropane-1, 3-diyl, pentane-1, 4-diyl, 2-methylbutane-1, 4-diyl, and the like; a cycloalkanediyl group such as cyclobutane-1, 3-diyl, cyclopentane-1, 3-diyl, cyclohexane-1, 4-diyl, cyclooctane-1, 5-diyl, and the like; a polycyclic divalent alicyclic hydrocarbon group such as norbornane-1, 4-diyl, norbornane-2, 5-diyl, adamantane-1, 5-diyl, adamantane-2, 6-diyl, and the like.

[0137] Among the above, an alkanediyl group is preferred, and a linear alkanediyl group is more preferred.

[0138] In the formula (a1-p1), Ra 08 represents a divalent linking group containing a hetero atom.

[0139] As Ra 08-O-, -C(=O)-O-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H can also be substituted by an alkyl group, an acyl group, or the like), -S-, -S(=O)2-, -S(=O)2-O-, or the like can be exemplified.

[0140] Of the above, from the viewpoint of solubility in a developer, -O-, -C(=O)-O-, -C(=O)-, -O-C(=O)-O- are preferred, and -O-, -C(=O)- are particularly preferred.

[0141] In the formula (a1-p1), Ra 06 represents a monovalent hydrocarbon group having a carbon number of 1 to 12. Ra 06 The carbon number of Ra

[0142] Ra 06 The hydrocarbon group in Ra

[0143] As the chain hydrocarbon group, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, a 2-ethylhexyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, or the like can be exemplified.

[0144] The cyclic hydrocarbon group can be an alicyclic hydrocarbon group or an aromatic hydrocarbon group.

[0145] As the alicyclic hydrocarbon group, either a monocyclic or a polycyclic one can be used, and as the monocyclic alicyclic hydrocarbon group, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, or the like can be exemplified. As the polycyclic alicyclic hydrocarbon group, for example, a decalinyl group, an adamantyl group, a (2-alkyladamant-2) group, a (1- (adamant-1-yl)alkane-1) group, a norbornyl group, a methyl-norbornyl group, an isobornyl group, or the like can be exemplified.

[0146] As the aromatic hydrocarbon group, for example, a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-t-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like can be exemplified.

[0147] As Ra 06 From the viewpoint of solubility in a developer, a chain hydrocarbon group is preferred, an alkyl group is more preferred, and a straight-chain alkyl group is further preferred.

[0148] In the formula (al-pl), n p0 is an integer of 1 to 6, preferably an integer of 1 to 3, more preferably 1 or 2, further preferably 1.

[0149] The following shows specific examples of the hydrocarbon group having at least a polar group.

[0150] In the following formula, * is a bond to a quaternary carbon atom (Ya 0 ).

[0151] [Chemical Formula 6]

[0152]

[0153] In the formula (al-r2-r1), Ra 031 , Ra 032 , and Ra 033 , the number of the hydrocarbon group having at least a polar group is preferably 1 or more, and is appropriately determined in consideration of solubility to a developing solution at the time of resist pattern formation, for example, preferably 1 or 2 of Ra 031 , Ra 032 , and Ra 033 have at least a polar group, particularly preferably 1 has at least a polar group.

[0154] The hydrocarbon group having at least a polar group can have a substituent other than the polar group. As the substituent, for example, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), a halogenated alkyl group having a carbon number of 1 to 5 can be exemplified.

[0155] In the formula (al-r2-1), Ra" 11 (bonding to the carbon atom of Ra' 10 ) is preferably a group exemplified as the alicyclic group or the polycyclic group of Ra' 3 in the formula (al-r-1).

[0156] In the formula (al-r2-2), as the cyclic hydrocarbon group formed together with Xaand Ya, a group obtained by further removing one or more hydrogen atoms from the cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) of Ra' 3 in the formula (al-r-1) can be exemplified.

[0157] The cyclic hydrocarbon group formed together with Xaand Ya can have a substituent. As the substituent, the same group as the substituent which the cyclic hydrocarbon group of Ra' 3 in the above can have can be exemplified.

[0158] In the formula (al-r2-2), as Ra 01~Ra 03 It is a monovalent chain saturated hydrocarbon group with 1 to 10 carbon atoms, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, etc.

[0159] As Ra 01 ~Ra 03 The carbon number in the group is 3 to 20. Examples of monocyclic aliphatic cyclic saturated hydrocarbon groups include: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, cyclododecyl, etc.; and bicyclic [2.2.2]octyl, tricyclic [5.2.1.02, 6]decyl, tricyclic [3.3.1.13, 7]decyl, tetracyclic [6.2.1.13, 6.02, 7]dodecyl, adamantyl, etc.

[0160] From the perspective of easily synthesizing monolithic compounds from which the structural unit (a1) can be derived, Ra 01 ~Ra 03 Preferably, it is a hydrogen atom or a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrogen atom, methyl, or ethyl, and particularly preferably a hydrogen atom.

[0161] As mentioned above, Ra 01 ~Ra 03 The substituents represented by the chain-like saturated hydrocarbon group or the aliphatic cyclic saturated hydrocarbon group can be exemplified by those related to the Ra group described above. 05 The same group.

[0162] As through Ra 01 ~Ra 03 A group consisting of two or more mutually bonded to form a cyclic structure and containing a carbon-carbon double bond, such as cyclopentenyl, cyclohexenyl, methylcyclopentenyl, methylcyclohexenyl, cyclopenteneylene, and cyclohexeneylene. From the viewpoint of easily synthesizing monolithic compounds from which the structural unit (a1) is derived, cyclopentenyl, cyclohexenyl, and cyclopenteneylene are preferred.

[0163] In formula (a1-r2-3), the aliphatic cyclic group formed by Xaa and Yaa together is preferably Ra' in formula (a1-r-1). 3 Examples of groups are aliphatic hydrocarbon groups, either monocyclic or polycyclic.

[0164] In equation (a1-r2-3), Ra is used as... 04 The aromatic hydrocarbon group in the text can be exemplified by groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Ra... 04Preferably, the group is one obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably one obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene, further preferably one obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene, particularly preferably one obtained by removing one or more hydrogen atoms from benzene or naphthalene, most preferably one obtained by removing one or more hydrogen atoms from benzene.

[0165] Ra in the formula (a1-r2-3) is 04 The substituent group that can be present includes, for example, a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), an alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), an alkoxycarbonyl group, etc.

[0166] Ra in the formula (a1-r2-4) is 12 Ra in the formula (a1-r2-4) is 13 Each of Ra and Ra is independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. As the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra 12 and Ra 13 , the same groups as those in Ra 01 to Ra 03 having 1 to 10 carbon atoms can be exemplified. Part or all of the hydrogen atoms possessed by the chain saturated hydrocarbon group can be substituted.

[0167] Ra in the formula (a1-r2-4) is 12 Ra in the formula (a1-r2-4) is 13 Preferably, Ra and Ra are a hydrogen atom, 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, an ethyl group, particularly preferably a methyl group.

[0168] In the case where the chain saturated hydrocarbon group represented by Ra 12 and Ra 13 is substituted, the same groups as those in the above-mentioned Ra 05 can be exemplified as the substituent group.

[0169] Ra in the formula (a1-r2-4) is 14 a hydrocarbon group that can have a substituent group. As the hydrocarbon group in Ra 14 , a linear or branched alkyl group or a cyclic hydrocarbon group can be exemplified.

[0170] The carbon number of the linear alkyl group in Ra 14 is preferably 1 to 5, more preferably 1 to 4, further preferably 1 or 2. Specifically, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, etc. can be exemplified. Among them, a methyl group, an ethyl group or an n-butyl group is preferred, a methyl group or an ethyl group is more preferred.

[0171] Ra' 14 The number of carbon atoms in the branched alkyl group in Ra 14 is preferably from 3 to 10, more preferably from 3 to 5. Specifically, examples include isopropyl, isobutyl, t-butyl, isopentyl, neopentyl, 1,1-diethylpropyl, 2,2-dimethylbutyl, and the like, with isopropyl being preferred.

[0172] In the case where Ra 14 is a cyclic hydrocarbon group, the hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and in addition, can be a polycyclic group or a monocyclic group.

[0173] As the aliphatic hydrocarbon group of the monocyclic group, a group obtained by removing one hydrogen atom from a monocyclic alkane is preferred. As the monocyclic alkane, a monocyclic alkane having a carbon number of from 3 to 6 is preferred, and specifically, examples include cyclopentane, cyclohexane, and the like.

[0174] As the aliphatic hydrocarbon group of the polycyclic group, a group obtained by removing one hydrogen atom from a polycyclic alkane is preferred, and as the polycyclic alkane, a polycyclic alkane having a carbon number of from 7 to 12 is preferred, and specifically, examples include adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like.

[0175] As the aromatic hydrocarbon group in Ra 14 , the same groups as the aromatic hydrocarbon groups in Ra 04 can be given. Of these, Ra 14 is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having a carbon number of from 6 to 15, more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or phenanthrene, further preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, or anthracene, particularly preferably a group obtained by removing one or more hydrogen atoms from naphthalene or anthracene, and most preferably a group obtained by removing one or more hydrogen atoms from naphthalene.

[0176] As the substituents that Ra 14 may have, the same groups as the substituents that Ra 04 may have can be given.

[0177] In the case where Ra 14 in the formula (a1-r2-4) is a naphthyl group, the position bonded to the tertiary carbon atom in the formula (a1-r2-4) can be any one of the 1-position or the 2-position of the naphthyl group.

[0178] In the case where Ra 14 in the formula (a1-r2-4) is an anthryl group, the position bonded to the tertiary carbon atom in the formula (a1-r2-4) can be any one of the 1-position, the 2-position, or the 9-position of the anthryl group.

[0179] Specific examples of the group represented by the formula (a1-r2-1) are given below.

[0180] [Chem. 7]

[0181]

[0182] [Chem. 8]

[0183]

[0184] [Chem. 9]

[0185]

[0186] The following illustrates specific examples of the group represented by the formula (al-r2-2).

[0187] [Chem. 10]

[0188]

[0189] [Chem. 11]

[0190]

[0191] [Chem. 12]

[0192]

[0193] The following illustrates specific examples of the group represented by the formula (al-r2-3).

[0194] [Chem. 13]

[0195]

[0196] The following illustrates specific examples of the group represented by the formula (al-r2-4).

[0197] [Chem. 14]

[0198]

[0199] Tertiary alkoxycarbonyl acid dissociation group:

[0200] As the acid dissociation group for protecting the hydroxyl group in the polar group, for example, the acid dissociation group represented by the following general formula (al-r-3) (hereinafter also referred to as "tertiary alkoxycarbonyl acid dissociation group" for convenience of explanation) can be exemplified.

[0201] [Chem. 15]

[0202]

[0203] [In the formula, Ra' 7 ~ Ra' 9 are each an alkyl group.

[0204] In formula (a1-r-3), Ra 7 ~Ra 9 Each of R and R is preferably an alkyl group having a carbon number of 1 to 5, more preferably an alkyl group having a carbon number of 1 to 3.

[0205] In addition, the total carbon number of each alkyl group is preferably 3 to 7, more preferably a carbon number of 3 to 5, and most preferably a carbon number of 3 to 4.

[0206] As the structural unit (a1), from the viewpoint of suppressing the decrease in light transmittance in a thick film resist film, it is preferable to contain an acid dissociation group represented by the general formula (a1-r-2), and more preferable to contain an acid dissociation group represented by the general formula (a1-r2-4). In the general formula (a1-r2-4), Ra 12 and Ra 13 Each of R and R is preferably an alkyl group having a carbon number of 1 to 5, more preferably an alkyl group having a carbon number of 1 to 3, further preferably a methyl group or an ethyl group, and particularly preferably a methyl group. In the general formula (a1-r2-4), Ra 14 is preferably an alkyl group having a carbon number of 1 to 5, more preferably an alkyl group having a carbon number of 1 to 3, further preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

[0207] As the structural unit (a1), examples include a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at an α-position can be substituted with a substituent; a structural unit derived from an acrylamide; a structural unit in which at least a part of hydrogen atoms in a hydroxyl group of a structural unit derived from a hydroxyl styrene or a hydroxyl styrene derivative is protected with a substituent containing the acid decomposable group; a structural unit in which at least a part of hydrogen atoms in -C(=O)-OH of a structural unit derived from a vinylbenzoic acid or a vinylbenzoic acid derivative is protected with a substituent containing the acid decomposable group, and the like.

[0208] As the structural unit (a1), among the above structural units, a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at an α-position can be substituted with a substituent is preferable. As a preferable specific example of the structural unit (a1), a structural unit represented by the following general formula (a1-1) or (a1-2) can be exemplified.

[0209] [Chemical Formula 16]

[0210]

[0211] [In the formula, R is a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a halogenated alkyl group having a carbon number of 1 to 5. Va 1 is a divalent hydrocarbon group which can have an ether bond. n a1 is an integer of 0 to 2. Ra 1is an acid dissociable group represented by the above general formula (al-r-l) or (al-r-2). Wa 1 is an integer of 1 to 3, n a2 is a hydrocarbon group of valence n a2 is an integer of 1 to 3, n 2 is an acid dissociable group represented by the above general formula (al-r-l) or (al-r-3).

[0212] In the formula (al-l), R is an alkyl group having a carbon number of 1 to 5, preferably a linear or branched alkyl group having a carbon number of 1 to 5, and specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a t-butyl group, a pentyl group, an isopentyl group, a neopentyl group, or the like. A halogenated alkyl group having a carbon number of 1 to 5 is a group in which part or all of the hydrogen atoms of the above alkyl group having a carbon number of 1 to 5 are substituted with halogen atoms. As the halogen atoms, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, or the like can be mentioned, and a fluorine atom is particularly preferred.

[0213] As R, a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a fluoroalkyl group having a carbon number of 1 to 5 is preferred, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is most preferred.

[0214] In the formula (al-l), Va 1 The divalent hydrocarbon group in Va

[0215] The divalent hydrocarbon group in Va 1 The aliphatic hydrocarbon group as the divalent hydrocarbon group in Va

[0216] More specifically, as the aliphatic hydrocarbon group, for example, a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group having a ring in the structure, or the like can be mentioned.

[0217] The carbon number of the linear aliphatic hydrocarbon group is preferably 1 to 10, more preferably 1 to 6, further preferably 1 to 4, and most preferably 1 to 3. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferred, and specifically, for example, a methylene group [-CH2-], an ethylene group [- (CH2)2-], a propylene group [- (CH2)3-], a butylene group [- (CH2)4-], a pentylene group [- (CH2)5-], or the like can be mentioned.

[0218] The number of carbons of the branched aliphatic hydrocarbon group is preferably from 2 to 10, more preferably from 3 to 6 in number of carbons, further preferably 3 or 4 in number of carbons, most preferably 3 in number of carbons. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, examples include alkyl methylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-, and the like; alkyl ethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-, and the like; alkyl propylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-, and the like; alkyl butylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2-, and the like; and the like. As the alkyl group in the alkyl alkylene group, a linear alkyl group having from 1 to 5 carbons in number of carbons is preferable.

[0219] As the ring-containing aliphatic hydrocarbon group in the structure, examples include an alicyclic hydrocarbon group (a group obtained by removing 2 hydrogen atoms from an aliphatic hydrocarbon ring); a group in which an alicyclic hydrocarbon group is bonded at the terminal of a linear or branched aliphatic hydrocarbon group; a group in which an alicyclic hydrocarbon group is interposed between linear or branched aliphatic hydrocarbon groups; and the like. As the linear or branched aliphatic hydrocarbon group, the same groups as the linear aliphatic hydrocarbon group or the branched aliphatic hydrocarbon group are preferable.

[0220] The number of carbons of the alicyclic hydrocarbon group is preferably from 3 to 20, more preferably from 3 to 12.

[0221] The alicyclic hydrocarbon group can be either a polycyclic or monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing 2 hydrogen atoms from a monocyclic alkane is preferable, and as the monocyclic alkane, a monocyclic alkane having from 3 to 6 carbons in number of carbons is preferable, and specifically, examples include cyclopentane, cyclohexane, and the like. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing 2 hydrogen atoms from a polycyclic alkane is preferable, and as the polycyclic alkane, a polycyclic alkane having from 7 to 12 carbons in number of carbons is preferable, and specifically, examples include adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like.

[0222] As the divalent hydrocarbon group in Va 1 The aromatic hydrocarbon group as the divalent hydrocarbon group in Va

[0223] The number of carbons of the above aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, most preferably 6 to 12. Among the number of carbons, the number of carbons in a substituent is not included. As the aromatic ring possessed by the aromatic hydrocarbon group, specifically, there can be mentioned an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene, and the like; an aromatic heterocyclic ring obtained by substituting a part of carbon atoms constituting the aromatic hydrocarbon ring with a hetero atom; and the like. As the hetero atom in the aromatic heterocyclic ring, there can be mentioned an oxygen atom, a sulfur atom, a nitrogen atom, and the like.

[0224] As the aromatic hydrocarbon group, specifically, there can be mentioned a group obtained by removing 2 hydrogen atoms from the aromatic hydrocarbon ring (an arylene group); a group obtained by substituting 1 hydrogen atom of a group obtained by removing 1 hydrogen atom from the aromatic hydrocarbon ring (an aryl group) with an alkylene group (for example, a group obtained by removing 1 hydrogen atom from an aryl group in an aralkyl group such as benzyl, phenylethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, and the like); and the like. The number of carbons of the alkylene group (alkyl chain in the aralkyl group) is preferably 1 to 4, more preferably 1 to 2, particularly preferably 1.

[0225] In the formula (a1-1), Ra 1 is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-2).

[0226] In the formula (a1-1), n a1 is an integer of 0 to 2. n a1 is preferably 0 or 1, more preferably 0.

[0227] In the formula (a1-2), Wa 1 is an integer of 0 to 2. n a2 The valence of the hydrocarbon group is +1. The hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group represents a hydrocarbon group having no aromaticity, and can be saturated or unsaturated, and is usually preferably saturated. As the aliphatic hydrocarbon group, there can be mentioned a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in the structure, or a group obtained by combining a linear or branched aliphatic hydrocarbon group with an aliphatic hydrocarbon group having a ring in the structure. The n a2 The valence of the hydrocarbon group is preferably 2 to 4, more preferably 2 or 3.

[0228] In the formula (a1-2), Ra 2 is an acid dissociable group represented by the above general formula (a1-r-1) or (a1-r-3).

[0229] Specific examples of the structural unit represented by the formula (a1-1) are shown below. In the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0230] [Chem. 17]

[0231]

[0232] [Chem. 18]

[0233]

[0234] [Chem. 19]

[0235]

[0236] [Chem. 20]

[0237]

[0238] [Chem. 21]

[0239]

[0240] [Chem. 22]

[0241]

[0242] [Chem. 23]

[0243]

[0244] [Chem. 24]

[0245]

[0246] [Chem. 25]

[0247]

[0248] [Chem. 26]

[0249]

[0250] [Chem. 27]

[0251]

[0252] The following shows specific examples of structural units represented by the formula (a1-2).

[0253] [Chem. 28]

[0254]

[0255] The structural unit (a1) possessed by the component (A1) can be one or two or more.

[0256] As the structural unit (a1), a structural unit represented by the formula (a1-1) is more preferable from the viewpoint of further improving the characteristics (sensitivity, shape, etc.) in lithography using electron beams or EUV.

[0257] As the structural unit (a1), a structural unit represented by the formula (a1-1) is more preferable from the viewpoint of further improving the characteristics (sensitivity, shape, etc.) in lithography using electron beams or EUV.

[0258] [Formula 29]

[0259]

[0260] [In the formula, Ra 1 is an acid dissociable group represented by the formula (a1-r2-1), (a1-r2-3) or (a1-r2-4).

[0261] In the formula (a1-1-1), R, Va 1 and n a1 are the same as R, Va 1 and n a1 in the formula (a1-1).

[0262] The acid dissociable group represented by the formula (a1-r2-1), (a1-r2-3) or (a1-r2-4) is as described above. From the viewpoint of maintaining transparency in a thick resist film, Ra 1 is preferably an acid dissociable group represented by the formula (a1-r2-4). Ra 12 , Ra 13 and Ra 14 in the formula (a1-r2-4) are preferable, for example, as described above.

[0263] The proportion of the structural unit (a1) in the (A1) component is preferably 5 to 80 mol%, more preferably 10 to 75 mol%, further preferably 30 to 70 mol%, particularly preferably 30 to 60 mol% relative to the total (100 mol%) of all the structural units constituting the (A1) component.

[0264] By setting the proportion of the structural unit (a1) to be the lower limit value or more of the preferable range, the lithography characteristics such as sensitivity, resolution, roughness improvement are improved. On the other hand, if it is the upper limit value or less of the preferable range, a balance with other structural units can be achieved and various lithography characteristics are good.

[0265] <Other Structural Units>

[0266] The (A1) component can have other structural units in addition to the above-described structural unit (a1) as necessary.

[0267] As other structural units, for example, there can be mentioned structural unit (a2) containing a lactone ring-containing cyclic group, a -SO2- containing cyclic group, a carbonate ring-containing cyclic group; structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group; structural unit (a4) containing an acid non-dissociative aliphatic cyclic group; structural unit (a10) represented by the following general formula (a10-1); structural unit (st) derived from styrene or a derivative thereof; and the like.

[0268] Regarding the structural unit (a2):

[0269] The (Al) component can further have, in addition to the structural unit (al), a structural unit (a2) containing a lactone ring-containing cyclic group, a -SO2- containing cyclic group, or a carbonate ring-containing cyclic group (wherein the structural unit belonging to the structural unit (al) is excluded).

[0270] In the case where the (Al) component is used for the formation of a resist film, the lactone ring-containing cyclic group, the -SO2- containing cyclic group, or the carbonate ring-containing cyclic group of the structural unit (a2) is effective in improving the adhesion of the resist film to a substrate. Further, by having the structural unit (a2), for example, the effects of appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to a substrate, appropriately adjusting the solubility at the time of development, and the like, the lithography characteristics and the like become good.

[0271] The "lactone ring-containing cyclic group" means a cyclic group containing a -O-C(=O)- containing ring (lactone ring) in the ring skeleton. The lactone ring is noted as the first ring, and is referred to as a monocyclic group in the case where only the lactone ring is present, and is referred to as a polycyclic group regardless of the structure in the case where other ring structures are also present. The lactone ring-containing cyclic group can be a monocyclic group or a polycyclic group.

[0272] As the lactone ring-containing cyclic group in the structural unit (a2), there is no particular limitation, and any lactone ring-containing cyclic group can be used. Specifically, there can be mentioned groups represented by the following general formulae (a2-r-1) to (a2-r-7), respectively.

[0273] [Chem. 30]

[0274]

[0275] [In the formula, Ra 21 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a haloalkyl 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 ring-containing cyclic group, a carbonate ring-containing cyclic group, or a -SO2- containing cyclic group; A" is an alkylene group having a carbon number of 1 to 5 which can 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.]

[0276] In the general formulas (a2-r-1) to (a2-r-7), Ra' is used as... 21 The alkyl group in the alkyl group is preferably an alkyl group having 1 to 6 carbon atoms. This alkyl group is preferably straight-chain or branched. Specifically, examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, and hexyl. Among these, methyl or ethyl is preferred, and methyl is particularly preferred.

[0277] As Ra' 21 The alkoxy group in the formula is preferably an alkoxy group having 1 to 6 carbon atoms. This alkoxy group is preferably linear or branched. Specifically, examples can be given as Ra'. 21 The alkyl group in the example is a group formed by attaching an alkyl group to an oxygen atom (-O-).

[0278] As Ra' 21 The halogen atoms in the atom can be fluorine, chlorine, bromine, iodine, etc., with fluorine atoms being preferred.

[0279] As Ra' 21 The haloalkyl group in it can be exemplified by Ra' 21 A group obtained by replacing some or all of the hydrogen atoms of the alkyl group with the halogen atom. The alkyl group is preferably a fluoroalkyl group, and particularly preferably a perfluoroalkyl group.

[0280] Ra' 21 In -COOR” and -OC(=O)R”, R” can be a hydrogen atom, alkyl group, lactone cyclic group, carbonate cyclic group or -SO2- cyclic group.

[0281] The alkyl group in "R" can be any of the following: linear, branched, or cyclic, and the number of carbon atoms is preferably 1 to 15.

[0282] When R” is a straight-chain or branched alkyl group, it is preferred to have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably methyl or ethyl.

[0283] When R” is a cyclic alkyl group, the number of carbon atoms is preferably 3 to 15, more preferably 4 to 12, and most preferably 5 to 10. Specifically, examples include groups obtained by removing one or more hydrogen atoms from monocyclic alkanes that can be substituted with or not substituted with fluorine atoms or fluoroalkyl groups; and groups obtained by removing one or more hydrogen atoms from polycyclic alkanes such as bicyclic alkanes, tricyclic alkanes, and tetracyclic alkanes. More specifically, examples include groups obtained by removing one or more hydrogen atoms from monocyclic alkanes such as cyclopentane and cyclohexane; and groups obtained by removing one or more hydrogen atoms from polycyclic alkanes such as adamantane, norbornane, isobornane, tricyclic decane, and tetracyclic dodecane.

[0284] As the lactone ring-containing cyclic group in R", the same groups as those represented by the general formulae (a2-r-1) to (a2-r-7) can be exemplified.

[0285] As the carbonate ring-containing cyclic group in R", the same groups as those described later can be exemplified, and specifically, the groups represented by the general formulae (ax3-r-1) to (ax3-r-3) can be exemplified.

[0286] As the -SO2- containing cyclic group in R", the same groups as those described later can be exemplified, and specifically, the groups represented by the general formulae (a5-r-1) to (a5-r-4) can be exemplified.

[0287] As the hydroxyalkyl group in Ra' 21 , a hydroxyalkyl group having a carbon number of 1 to 6 is preferred, and specifically, a group in which at least one hydrogen atom of the alkyl group in Ra' 21 is substituted with a hydroxy group can be exemplified.

[0288] In the general formulae (a2-r-2), (a2-r-3), and (a2-r-5), as the alkylene group having a carbon number of 1 to 5 in A", a linear or branched alkylene group is preferred, and methylene, ethylene, n-propylene, iso-propylene, and the like can be exemplified. In the case where the alkylene group contains an oxygen atom or a sulfur atom, as specific examples thereof, a group in which the terminal or the carbon atom of the alkylene group is intervened with -O- or -S- can be exemplified, and for example, -O-CH2-, -CH2-O-CH2-, -S-CH2-, -CH2-S-CH2-, and the like can be exemplified. As A", an alkylene group having a carbon number of 1 to 5 or -O- is preferred, an alkylene group having a carbon number of 1 to 5 is more preferred, and methylene is most preferred.

[0289] Specific examples of the groups represented by the general formulae (a2-r-1) to (a2-r-7) are exemplified below.

[0290] [Chem. 31]

[0291]

[0292] [Chem. 32]

[0293]

[0294] "SO2-containing cyclic group" means a cyclic group having a ring containing -SO2- in its ring skeleton, and specifically, a cyclic group in which the sulfur atom (S) in -SO2- forms part of the ring skeleton of the cyclic group. The ring containing -SO2- is counted as the first ring in the ring skeleton, and is referred to as a monocyclic group in the case of having only this ring, and as a polycyclic group regardless of its structure in the case of having other ring structures as well. The SO2-containing cyclic group can be either a monocyclic group or a polycyclic group.

[0295] The SO2-containing cyclic group is particularly preferably a cyclic group having a ring containing -O-SO2- in its ring skeleton, i.e., a cyclic group having a sultone ring containing -O-S- in -O-SO2- as part of the ring skeleton.

[0296] As the SO2-containing cyclic group, more specifically, there can be mentioned groups represented by the following general formulae (a5-r-1) to (a5-r-4), respectively.

[0297] [Chemical Formula 33]

[0298]

[0299] [In the formula, Ra' 51 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a haloalkyl group, a hydroxy 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 a SO2-containing cyclic group; A" is an alkylene group having 1 to 5 carbon atoms which can contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom, and n' is an integer of 0 to 2.]

[0300] In the general formulae (a5-r-1) to (a5-r-2), A" is the same as A" in the general formulae (a2-r-2), (a2-r-3), and (a2-r-5).

[0301] As the alkyl group, alkoxy group, halogen atom, haloalkyl group, -COOR", -OC(=O)R", hydroxyalkyl group, and cyano group in Ra' 51 , there can be mentioned the same groups as those exemplified in the description of Ra' 21 in the general formulae (a2-r-1) to (a2-r-7).

[0302] Specific examples of the groups represented by the general formulae (a5-r-1) to (a5-r-4), respectively, are exemplified below. "Ac" in the formula means an acetyl group.

[0303] [Chemical Formula 34]

[0304]

[0305] [Chem. 35]

[0306]

[0307] [Chem. 36]

[0308]

[0309] "Carbonate ring-containing cyclic group" means a cyclic group containing a -O-C(=O)-O- containing ring (carbonate ring) in its ring skeleton. The carbonate ring is noted as the first ring, and is referred to as a monocyclic group in the case of only the carbonate ring, and as a polycyclic group in the case of also having other ring structures, regardless of the structure thereof. The carbonate ring-containing cyclic group can be either a monocyclic group or a polycyclic group.

[0310] As the carbonate ring-containing cyclic group, there is no particular limitation, and any carbonate ring-containing cyclic group can be used. Specifically, groups represented by the following general formulae (ax3-r-1) to (ax3-r-3), respectively, can be exemplified.

[0311] [Chem. 37]

[0312]

[0313] [In the formula, Ra' x31 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a haloalkyl group, a hydroxy group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone ring-containing cyclic group, a carbonate ring-containing cyclic group, or a -SO2- containing cyclic group; A" is an alkylene group having a carbon number of 1 to 5 which can 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.]

[0314] 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).

[0315] As the alkyl group, alkoxy group, halogen atom, haloalkyl group, -COOR", -OC(=O)R", hydroxyalkyl group in Ra' 31 , the same groups as those exemplified in the description of Ra' 21 in the general formulae (a2-r-1) to (a2-r-7) can be exemplified, respectively.

[0316] Specific examples of groups represented by the general formulae (ax3-r-1) to (ax3-r-3), respectively, are exemplified below.

[0317] [Chem. 38]

[0318]

[0319] As the structural unit (a2), among them, a propenoate-derived structural unit in which a hydrogen atom bonded to a carbon atom at an α-position can be substituted with a substituent is preferable.

[0320] The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

[0321] [Chem. 39]

[0322]

[0323] [In the formula, R is a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a halogenated alkyl group having a carbon number of 1 to 5. Ya 21 is a single bond or a divalent linking group. La 21 is -0-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, and R' represents a hydrogen atom or a methyl group. Among them, in the case where La 21 is -0-, Ya 21 cannot be -CO-. Ra 21 is a lactone ring-containing group, a carbonate ring-containing group, or a -SO2- ring-containing group.

[0324] In the formula (a2-1), R is the same as described above. As R, a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a fluorinated alkyl group having a carbon number of 1 to 5 is preferable, and a hydrogen atom or a methyl group is particularly preferable from the viewpoint of industrial availability.

[0325] In the formula (a2-1), as Ya 21 is not particularly limited, and a divalent hydrocarbon group which can have a substituent, a heteroatom-containing divalent linking group, and the like can be preferable.

[0326] • a divalent hydrocarbon group which can have a substituent:

[0327] In the case where Ya 21 is a divalent hydrocarbon group which can have a substituent, the hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0328] ·· Ya 21 is an aliphatic hydrocarbon group

[0329] The aliphatic hydrocarbon group indicates a hydrocarbon group which does not have aromaticity. The aliphatic hydrocarbon group can be saturated or unsaturated, and is usually preferable to be saturated. As the aliphatic hydrocarbon group, a straight-chain or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure, and the like can be exemplified.

[0330] ··· straight-chain or branched aliphatic hydrocarbon group

[0331] The number of carbon atoms of the linear aliphatic hydrocarbon group is preferably from 1 to 10, more preferably from 1 to 6, further preferably from 1 to 4, and most preferably from 1 to 3.

[0332] As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, methylene [-CH2-], ethylene [- (CH2)2-], propylene [- (CH2)3-], butylene [- (CH2)4-], pentylene [- (CH2)5-], and the like can be exemplified.

[0333] The number of carbon atoms of the branched aliphatic hydrocarbon group is preferably from 2 to 10, more preferably from 3 to 6, further preferably 3 or 4, and most preferably 3.

[0334] As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, alkylmethylene groups such as -CH (CH3) -, -CH (CH2CH3) -, -C (CH3)2-, -C (CH3) (CH2CH3) -, -C (CH3) (CH2CH2CH3) -, -C (CH2CH3)2-, and the like; alkylethylene groups such as -CH (CH3) CH2-, -CH (CH3) CH (CH3) -, -C (CH3)2CH2-, -CH (CH2CH3) CH2-, -C (CH2CH3)2CH2-, and the like; alkylpropylene groups such as -CH (CH3) CH2CH2-, -CH2CH (CH3) CH2-, and the like; alkylbutylene groups such as -CH (CH3) CH2CH2CH2-, -CH2CH (CH3) CH2CH2-, and the like; and the like can be exemplified. As the alkyl group in the alkylalkylene group, a linear alkyl group having from 1 to 5 carbon atoms is preferable.

[0335] The linear or branched aliphatic hydrocarbon group can have a substituent or can not have a substituent. As the substituent, a fluorine atom, a fluoroalkyl group having from 1 to 5 carbon atoms substituted with a fluorine atom, a carbonyl group, and the like can be exemplified.

[0336] Aliphatic hydrocarbon group having a ring in the structure

[0337] As the aliphatic hydrocarbon group having a ring in the structure, a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which can have a substituent, a group obtained by bonding the cyclic aliphatic hydrocarbon group to the end of a linear or branched aliphatic hydrocarbon group, a group in which the cyclic aliphatic hydrocarbon group is interposed between linear or branched aliphatic hydrocarbon groups, and the like can be exemplified. As the linear or branched aliphatic hydrocarbon group, the same aliphatic hydrocarbon group as described above can be exemplified.

[0338] The number of carbon atoms of the cyclic aliphatic hydrocarbon group is preferably from 3 to 20, and more preferably from 3 to 12.

[0339] The cyclic aliphatic hydrocarbon group can be a polycyclic group or a monocyclic group. As the monocyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, a monocycloalkane having 3 to 6 carbon atoms is preferable, and specifically, cyclopentane, cyclohexane and the like can be given. As the polycyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferable, and as the polycycloalkane, a polycycloalkane having 7 to 12 carbon atoms is preferable, and specifically, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like can be given.

[0340] The cyclic aliphatic hydrocarbon group can have a substituent or can not have a substituent. As the substituent, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like can be given.

[0341] As the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and more preferably, a methyl group, an ethyl group, a propyl group, an n-butyl group, a t-butyl group.

[0342] As the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and more preferably, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a t-butoxy group, and further preferably, a methoxy group, an ethoxy group.

[0343] As the substituent, a halogen atom can be given a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and preferably, a fluorine atom.

[0344] As the substituent, a halogenated alkyl group can be given a group obtained by substituting a part or all of the hydrogen atoms of the alkyl group with the halogen atom.

[0345] A part of the carbon atoms constituting the ring structure of the cyclic aliphatic hydrocarbon group can also be substituted with a heteroatom-containing substituent. As the heteroatom-containing substituent, -0-, -C(=0)-0-, -S-, -S(=0)2-, -S(=0)2-0- are preferable.

[0346] ••• Ya 21 aromatic hydrocarbon group in the formula (1)

[0347] The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

[0348] The aromatic ring, if it is a cyclic conjugated system having 4n+2 π electrons, is not particularly limited, and can be monocyclic or polycyclic. The number of carbons of the aromatic ring is preferably 5 to 30, more preferably 5 to 20, further preferably 6 to 15, and particularly preferably 6 to 12. Among the number of carbons, the number of carbons in the substituent is not included.

[0349] Examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles formed by replacing a portion of the carbon atoms in the aforementioned aromatic hydrocarbon rings with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0350] Specifically, examples of aromatic hydrocarbon groups include groups (aryl or heteroaryl) obtained by removing two hydrogen atoms from an aromatic hydrocarbon ring or aromatic heterocycle; groups obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups obtained by substituting one hydrogen atom of an aryl or heteroaryl group obtained by removing one hydrogen atom from an aryl group (e.g., a group obtained by further removing one hydrogen atom from an aryl group among aryl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.). The alkylene group bonded to the aryl or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0351] In the aromatic hydrocarbon group, the hydrogen atoms present in the aromatic hydrocarbon group may also be replaced by substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon group may be replaced by substituents. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, haloalkyl groups, and hydroxyl groups.

[0352] The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably methyl, ethyl, propyl, n-butyl, or tert-butyl.

[0353] The alkoxy, halogen atom, and haloalkyl groups that are said to be substituents can be exemplified as substituents that replace the hydrogen atoms of the cyclic aliphatic hydrocarbon group.

[0354] • Divalent linking groups containing heteroatoms:

[0355] In Ya 21 In the case of a divalent linking group containing a heteroatom, examples of such linking groups include -O-, -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H can be substituted by alkyl, acyl, or other substituents), -S-, -S(=O)2-, -S(=O)2-O-, and those with the 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 -O-C(=O)-Y 22 - or -Y 21 -S(=O)2-O-Y 22 - represents a group [in the formula, Y 21 and Y 22 are each independently a divalent hydrocarbon group which can have a substituent, O is an oxygen atom, and m" is an integer of 0 to 3] as a preferred group.

[0356] In the case where the divalent linking group containing a hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=O)-, the H thereof can be substituted with an alkyl group, an acyl group, or the like. The carbon number of this substituent (alkyl group, acyl group, or the like) is preferably 1 to 10, further preferably 1 to 8, and particularly preferably 1 to 5.

[0357] General formula -Y 21 -O-Y 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-O-Y 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -O-C(=O)-Y 22 - or -Y 21 -S(=O)2-O-Y 22 - represents a group [in the formula, Y 21 and Y 22 are each independently a divalent hydrocarbon group which can have a substituent. As this divalent hydrocarbon group, the same groups as those exemplified in the explanation of the divalent linking group in the general formula -Ya 21

[0358] As Y 21 , a linear aliphatic hydrocarbon group is preferred, a linear alkylene group is more preferred, a linear alkylene group having a carbon number of 1 to 5 is further preferred, and a methylene group or an ethylene group is particularly preferred.

[0359] As Y 22 , a linear aliphatic hydrocarbon group or a branched aliphatic hydrocarbon group is preferred, a methylene group, an ethylene group, or an alkylmethylene group is more preferred. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having a carbon number of 1 to 5, more preferably a linear alkyl group having a carbon number of 1 to 3, and most preferably a methyl group.

[0360] ​a group represented by the formula: -Y 21 -C(=O)-O] m” -Y 22 In the group represented by the formula: -Y 21 -C(=O)-O] m” -Y 22 In the group represented by the formula: -Y 21 -C(=O)-O-Y 22 -C(=O)-O-Y a’ -C(=O)-O-(CH2) b’ -C(=O)-O-(CH2) 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, further preferably 1 or 2, 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, further preferably 1 or 2, most preferably 1.

[0361] Among the above, as Ya 21 , preferably a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0362] In the formula (a2-1), Ra 21 is a lactone ring-containing cyclic group, an -SO2- containing cyclic group, or a carbonate ring-containing cyclic group.

[0363] As the lactone ring-containing cyclic group, the -SO2- containing cyclic group, and the carbonate ring-containing cyclic group in Ra 21 , the above-mentioned groups represented by the general formulae (a2-r-1) to (a2-r-7), the groups represented by the general formulae (a5-r-1) to (a5-r-4), and the groups represented by the general formulae (ax3-r-1) to (ax3-r-3), respectively, can be preferably exemplified.

[0364] Among them, preferably a lactone ring-containing cyclic group or an -SO2- containing cyclic group, more preferably a group represented by the general formula (a2-r-1), (a2-r-2), (a2-r-6), or (a5-r-1), respectively. Specifically, more preferably any one of the groups represented by the chemical formulae (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), (r-sl-1-18), respectively.

[0365] The structural unit (a2) possessed by the component (A1) can be one or two or more.

[0366] In the case where the (Al) component has the structural unit (a2), the proportion of the structural unit (a2) is preferably 5 to 60 mol%, more preferably 10 to 60 mol%, further preferably 20 to 55 mol%, particularly preferably 30 to 50 mol%, relative to the total (100 mol%) of all the structural units constituting the (Al) component.

[0367] If the proportion of the structural unit (a2) is above the lower limit of the preferable range, the effect of the structural unit (a2) can be sufficiently obtained by the above-mentioned effects, and if it is below the upper limit, a balance with other structural units can be achieved, and various lithography characteristics become good.

[0368] Regarding the structural unit (a3):

[0369] The (Al) component can further have, in addition to the structural unit (al), a structural unit (a3) containing a polar-group-containing aliphatic hydrocarbon group (wherein the structural unit is not included in the structural unit (al) or the structural unit (a2)). By having the structural unit (a3) in the (Al) component, the hydrophilicity of the (A) component is increased, thereby contributing to an improvement in resolution. Furthermore, the acid diffusion length can be appropriately adjusted.

[0370] As the polar group, a hydroxyl group, a cyano group, a carboxyl group, a hydroxyalkyl group in which a part of the hydrogen atoms of an alkyl group is substituted with a fluorine atom, or the like can be exemplified, and a hydroxyl group is particularly preferable.

[0371] As the aliphatic hydrocarbon group, a linear or branched hydrocarbon group (preferably an alkylene group) having a carbon number of 1 to 10, a cyclic aliphatic hydrocarbon group (cyclic group) can be exemplified. As the cyclic group, a monocyclic group or a polycyclic group can be used, and for example, in a resin for an ArF excimer laser resist composition, a cyclic group mentioned several times above can be appropriately selected and used.

[0372] In the case where the cyclic group is a monocyclic group, a carbon number of 3 to 10 is more preferable. Among them, a structural unit derived from an acrylic ester containing an aliphatic monocyclic group having a hydroxyl group, a cyano group, a carboxyl group, or a hydroxyalkyl group in which a part of the hydrogen atoms of an alkyl group is substituted with a fluorine atom is more preferable. As the monocyclic group, a group obtained by removing two or more hydrogen atoms from a monocycloalkane can be exemplified. Specifically, a group obtained by removing two or more hydrogen atoms from a monocycloalkane such as cyclopentane, cyclohexane, cyclooctane, or the like can be exemplified. Among these monocyclic groups, a group obtained by removing two or more hydrogen atoms from cyclopentane, a group obtained by removing two or more hydrogen atoms from cyclohexane are industrially preferable.

[0373] 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, more preferably, a structural unit derived from an acrylate ester containing an aliphatic polycyclic group having a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group of a hydroxyl group, a cyano group, a carboxyl group, or an alkyl group is substituted with a fluorine atom. As the polycyclic group, a group obtained by removing two or more hydrogen atoms from a bicycloalkane, a tricycloalkane, a tetracycloalkane, or the like can be exemplified. Specifically, a group obtained by removing two or more hydrogen atoms from a polycyclic alkane such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like can be exemplified. Among these polycyclic groups, a group obtained by removing two or more hydrogen atoms from adamantane; a group obtained by removing two or more hydrogen atoms from norbornane; and a group obtained by removing two or more hydrogen atoms from tetracyclododecane are industrially preferable.

[0374] As the structural unit (a3), there is no particular limitation as long as it contains an aliphatic hydrocarbon group containing a polar group, and any structural unit can be used.

[0375] As the structural unit (a3), it is preferable that it be a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at an α position is substitutable with a substituent, and an aliphatic hydrocarbon group containing a polar group.

[0376] As the structural unit (a3), when the aliphatic hydrocarbon group containing a polar group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, it is preferable that it be a structural unit derived from a hydroxyethyl ester of acrylic acid.

[0377] Further, as the structural unit (a3), when the aliphatic hydrocarbon group containing a polar group is a polycyclic group, a structural unit represented by formula (a3-1) below, a structural unit represented by formula (a3-2) below, and a structural unit represented by formula (a3-3) below can be preferably exemplified; and when it is a monocyclic group, a structural unit represented by formula (a3-4) below can be preferably exemplified.

[0378] [Chemical Formula 40]

[0379]

[0380] [In the formula, R is the same as described above, j is an integer of 1 to 3, k is an integer of 1 to 3, t' is an integer of 1 to 3, and l is an integer of 0 to 5, and s is an integer of 1 to 3.]

[0381] In formula (a3-1), j is preferably 1 or 2, and further preferably 1. In the case where j is 2, it is preferable that the hydroxyl group be bonded to the 3- and 5-positions of the adamantyl group. In the case where j is 1, it is preferable that the hydroxyl group be bonded to the 3-position of the adamantyl group. j is preferably 1, and particularly preferably the hydroxyl group is bonded to the 3-position of the adamantyl group.

[0382] In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5- or 6-position of the norbornyl group.

[0383] In formula (a3-3), t' is preferably 1. 1 is preferably 1. s is preferably 1. Preferably, they are bonded to the terminal of the carboxyl group of acrylic acid with 2-norbornyl or 3-norbornyl. The fluoroalkyl alcohol is preferably bonded to the 5- or 6-position of the norbornyl group.

[0384] In formula (a3-4), t' is preferably 1 or 2. 1 is preferably 0 or 1. s is preferably 1. The fluoroalkyl alcohol is preferably bonded to the 3- or 5-position of the cyclohexyl group.

[0385] The structural unit (a3) possessed by the (Al) component can be one or two or more.

[0386] In the case where the (Al) component has the structural unit (a3), the proportion of the structural unit (a3) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and further preferably 5 to 20 mol%, relative to the total (100 mol%) of all the structural units constituting the (Al) component.

[0387] By making the proportion of the structural unit (a3) be the preferable lower limit value or more, the effect of containing the structural unit (a3) can be sufficiently obtained by the above-mentioned effects, and if it is the preferable upper limit value or less, a balance with other structural units can be achieved, and various lithography characteristics become good.

[0388] Regarding the structural unit (a4):

[0389] The (Al) component can further have, in addition to the structural unit (al), a structural unit (a4) containing an aliphatic cyclic group which is not dissociated by an acid.

[0390] By making the (Al) component have the structural unit (a4), the dry etching resistance of the resist pattern formed is improved. Furthermore, the hydrophobicity of the (A) component is improved. In particular, in the case of a solvent developing process, the improvement in hydrophobicity contributes to the improvement in resolution, resist pattern shape, and the like.

[0391] The "cyclic group which is not dissociated by an acid" in the structural unit (a4) is a cyclic group which, when an acid is generated in the resist composition by exposure (for example, when an acid is generated from a structural unit which generates an acid by exposure or the (B) component), is not dissociated even under the action of the acid and remains directly in the structural unit.

[0392] As the structural unit (a4), for example, a structural unit derived from an acrylic acid ester containing an aliphatic ring group which is not dissociated by an acid, and the like are preferred. The ring group can use various groups known in the past as a group for a resin component of a resist composition for an ArF excimer laser, a KrF excimer laser (preferably, an ArF excimer laser), and the like.

[0393] From the viewpoint of industrial availability and the like, the ring group is particularly preferably at least one selected from the group consisting of tricyclodecyl group, adamantyl group, tetracyclododecyl group, isobornyl group, norbornyl group. These polycyclic ring groups can have a linear or branched alkyl group having a carbon number of 1 to 5 as a substituent.

[0394] As the structural unit (a4), specifically, a structural unit represented by the following general formula (a4-1) to (a4-7), respectively, can be exemplified.

[0395] [Chemical Formula 41]

[0396]

[0397] [In the formula, R α The same as above.

[0398] The structural unit (a4) possessed by the (Al) component can be one or two or more.

[0399] In the case where the (Al) component has the structural unit (a4), the proportion of the structural unit (a4) is preferably 1 to 40 mol%, and more preferably 5 to 20 mol% with respect to the total (100 mol%) of all the structural units constituting the (Al) component.

[0400] By setting the proportion of the structural unit (a4) to be more than the lower limit of the preferred range, the effect of containing the structural unit (a4) can be sufficiently obtained, and on the other hand, by setting it to be less than the upper limit of the preferred range, a balance with other structural units can be easily obtained.

[0401] Regarding the structural unit (a10):

[0402] The structural unit (a10) is a structural unit represented by the following general formula (a10-1).

[0403] [Chemical Formula 42]

[0404]

[0405] [In the formula, R is a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a halogenated alkyl group having a carbon number of 1 to 5. Ya x1 is a single bond or a divalent linking group. Wa x1 is (n ax1+1) valent aromatic hydrocarbon group. n ax1 is an integer of 1 or more.

[0406] In the formula (a10-1), R is a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a halogenated alkyl group having a carbon number of 1 to 5.

[0407] The alkyl group having a carbon number of 1 to 5 in R is preferably a linear or branched alkyl group having a carbon number of 1 to 5, and specifically, examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a t-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and the like.

[0408] The halogenated alkyl group having a carbon number of 1 to 5 in R is a group in which a part or all of the hydrogen atoms of the alkyl group having a carbon number of 1 to 5 are substituted with halogen atoms. As the halogen atoms, examples include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like, and a fluorine atom is particularly preferred.

[0409] R is preferably a hydrogen atom, an alkyl group having a carbon number of 1 to 5, or a fluorinated alkyl group having a carbon number of 1 to 5, and from the viewpoint of industrial availability, a hydrogen atom, a methyl group, or a trifluoromethyl group is more preferred, a hydrogen atom or a methyl group is further preferred, and a methyl group is particularly preferred.

[0410] In the formula (a10-1), Ya x1 is a single bond or a divalent linking group.

[0411] In the formula, as the divalent linking group in Ya x1 there is no particular limitation, and examples of preferred linking groups include a divalent hydrocarbon group which can have a substituent, a heteroatom-containing divalent linking group, and the like.

[0412] • a divalent hydrocarbon group which can have a substituent:

[0413] In the case where Ya x1 is a divalent hydrocarbon group which can have a substituent, the hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0414] • the aliphatic hydrocarbon group in Ya x1

[0415] The aliphatic hydrocarbon group indicates a hydrocarbon group which does not have aromaticity. The aliphatic hydrocarbon group can be saturated or unsaturated, and is generally preferably saturated. As the aliphatic hydrocarbon group, examples include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure, and the like.

[0416] • a linear or branched aliphatic hydrocarbon group

[0417] ​The number of carbon atoms of the straight-chain aliphatic hydrocarbon group is preferably from 1 to 10, more preferably from 1 to 6, further preferably from 1 to 4, and most preferably from 1 to 3.

[0418] As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferable, and specifically, methylene [-CH2-], ethylene [- (CH2)2-], propylene [- (CH2)3-], butylene [- (CH2)4-], pentylene [- (CH2)5-], and the like can be exemplified.

[0419] The number of carbon atoms of the branched aliphatic hydrocarbon group is preferably from 2 to 10, more preferably from 3 to 6, further preferably 3 or 4, and most preferably 3.

[0420] As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, alkylmethylene groups such as -CH (CH3) -, -CH (CH2CH3) -, -C (CH3)2-, -C (CH3) (CH2CH3) -, -C (CH3) (CH2CH2CH3) -, -C (CH2CH3)2-, and the like; alkylethylene groups such as -CH (CH3) CH2-, -CH (CH3) CH (CH3) -, -C (CH3)2CH2-, -CH (CH2CH3) CH2-, -C (CH2CH3)2CH2-, and the like; alkylpropylene groups such as -CH (CH3) CH2CH2-, -CH2CH (CH3) CH2-, and the like; alkylbutylene groups such as -CH (CH3) CH2CH2CH2-, -CH2CH (CH3) CH2CH2-, and the like; and the like can be exemplified. As the alkyl group in the alkylalkylene group, a straight-chain alkyl group having a number of carbon atoms of from 1 to 5 is preferable.

[0421] The straight-chain or branched aliphatic hydrocarbon group can have a substituent or can not have a substituent. As the substituent, a fluorine atom, a fluoroalkyl group having a number of carbon atoms of from 1 to 5 substituted with a fluorine atom, a carbonyl group, and the like can be exemplified.

[0422] Aliphatic hydrocarbon group having a ring in the structure

[0423] As the aliphatic hydrocarbon group having a ring in the structure, a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which can have a substituent, a group obtained by bonding the cyclic aliphatic hydrocarbon group to the end of a straight-chain or branched aliphatic hydrocarbon group, a group in which the cyclic aliphatic hydrocarbon group is interposed between straight-chain or branched aliphatic hydrocarbon groups, and the like can be exemplified. As the straight-chain or branched aliphatic hydrocarbon group, the same aliphatic hydrocarbon groups as described above can be exemplified.

[0424] The number of carbon atoms of the cyclic aliphatic hydrocarbon group is preferably from 3 to 20, and more preferably from 3 to 12.

[0425] The cyclic aliphatic hydrocarbon group can be a polycyclic group or a monocyclic group. As the monocyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, a monocycloalkane having 3 to 6 carbon atoms is preferable, and specifically, cyclopentane, cyclohexane and the like can be given. As the polycyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferable, and as the polycycloalkane, a polycycloalkane having 7 to 12 carbon atoms is preferable, and specifically, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like can be given.

[0426] The cyclic aliphatic hydrocarbon group can have a substituent or can not have a substituent. As the substituent, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like can be given.

[0427] As the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and more preferably, a methyl group, an ethyl group, a propyl group, an n-butyl group, a t-butyl group.

[0428] As the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and more preferably, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a t-butoxy group, and further preferably, a methoxy group, an ethoxy group.

[0429] As the substituent, a halogen atom can be given a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and preferably, a fluorine atom.

[0430] As the substituent, a halogenated alkyl group can be given a group obtained by substituting a part or all of the hydrogen atoms of the alkyl group with the halogen atom.

[0431] A part of the carbon atoms constituting the ring structure of the cyclic aliphatic hydrocarbon group can also be substituted with a hetero atom-containing substituent. As the hetero atom-containing substituent, -0-, -C(=0)-0-, -S-, -S(=0)2-, -S(=0)2-0- are preferable.

[0432] The aromatic hydrocarbon group in the formula (1) is a hydrocarbon group having at least one aromatic ring. x1

[0433] The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

[0434] The aromatic ring, if it is a cyclic conjugated system having 4n+2 π electrons, is not particularly limited, and can be monocyclic or polycyclic. The number of carbons of the aromatic ring is preferably 5 to 30, more preferably 5 to 20, further preferably 6 to 15, and particularly preferably 6 to 12. Among the number of carbons, the number of carbons in the substituent is not included.

[0435] ​Examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles formed by replacing a portion of the carbon atoms in the aforementioned aromatic hydrocarbon rings with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0436] Specifically, examples of aromatic hydrocarbon groups include groups (aryl or heteroaryl) obtained by removing two hydrogen atoms from an aromatic hydrocarbon ring or aromatic heterocycle; groups obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups obtained by substituting one hydrogen atom of an aryl or heteroaryl group obtained by removing one hydrogen atom from an aryl group (e.g., a group obtained by further removing one hydrogen atom from an aryl group among aryl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.). The alkylene group bonded to the aryl or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0437] In the aromatic hydrocarbon group, the hydrogen atoms present in the aromatic hydrocarbon group may also be replaced by substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon group may be replaced by substituents. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, haloalkyl groups, and hydroxyl groups.

[0438] The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably methyl, ethyl, propyl, n-butyl, or tert-butyl.

[0439] The alkoxy, halogen atom, and haloalkyl groups that are said to be substituents can be exemplified as substituents that replace the hydrogen atoms of the cyclic aliphatic hydrocarbon group.

[0440] • Divalent linking groups containing heteroatoms:

[0441] In Ya x1 In the case of a divalent linking group containing a heteroatom, examples of such linking groups include -O-, -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H can be substituted by alkyl, acyl, or other substituents), -S-, -S(=O)2-, -S(=O)2-O-, and those with the 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 -O-C(=O)-Y 22 - or -Y 21 -S(=O)2-O-Y 22 - represents a group [in the formula, Y 21 and Y 22 are each independently a divalent hydrocarbon group which can have a substituent, O is an oxygen atom, and m" is an integer of 0 to 3] and the like as a preferred group.

[0442] In the case where the divalent linking group containing a hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=O)-, the H thereof can be substituted with an alkyl group, an acyl group, or the like. The carbon number of this substituent (alkyl group, acyl group, or the like) is preferably 1 to 10, further preferably 1 to 8, and particularly preferably 1 to 5.

[0443] General Formula -Y 21 -O-Y 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-O-Y 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -O-C(=O)-Y 22 - or -Y 21 -S(=O)2-O-Y 22 - represents a group [in the formula, Y 21 and Y 22 are each independently a divalent hydrocarbon group which can have a substituent. As this divalent hydrocarbon group, the same groups as those exemplified in the explanation of the divalent linking group in the General Formula Ya x1

[0444] As Y 21 , a linear aliphatic hydrocarbon group is preferred, a linear alkylene group is more preferred, a linear alkylene group having a carbon number of 1 to 5 is further preferred, and a methylene group or an ethylene group is particularly preferred.

[0445] As Y 22 , a linear aliphatic hydrocarbon group or a branched aliphatic hydrocarbon group is preferred, a methylene group, an ethylene group, or an alkylmethylene group is more preferred. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having a carbon number of 1 to 5, more preferably a linear alkyl group having a carbon number of 1 to 3, and most preferably a methyl group.

[0446] ​a group represented by the formula: -Y 21 -C(=O)-O] m” -Y 22 In the group represented by the formula: -Y 21 -C(=O)-O] m” -Y 22 In the group represented by the formula: -Y 21 -C(=O)-O-Y 22 In the group represented by the formula: -Y a’ -C(=O)-O-(CH2) b’ -C(=O)-O-(CH2) 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, further preferably 1 or 2, 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, further preferably 1 or 2, most preferably 1.

[0447] Among the above, as Ya x1 is preferably a single bond, an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof, more preferably a single bond, an ester bond [-C(=O)-O-, -O-C(=O)-], further preferably a single bond.

[0448] In the formula (a10-1), Wa x1 is an aromatic hydrocarbon group having (n ax1 +1) valences.

[0449] As the aromatic hydrocarbon group in Wa x1 , a group obtained by removing (n ax1 +1) hydrogen atoms from an aromatic ring can be exemplified. The aromatic ring herein is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and can be monocyclic or polycyclic. The carbon number of the aromatic ring is preferably 5 to 30, more preferably 5 to 20, further preferably 6 to 15, particularly preferably 6 to 12. As the aromatic ring, specifically, aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings obtained by substituting a part of carbon atoms constituting the aromatic hydrocarbon ring with a hetero atom can be exemplified. As the hetero atom in the aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, and the like can be exemplified. As the aromatic heterocyclic ring, specifically, pyridine rings, thiophene rings, and the like can be exemplified.

[0450] Further, as the aromatic hydrocarbon group in Wa x1 , a group obtained by removing (nax1 +1) hydrogen atoms.

[0451] Among the above, as Wa x1 , preferably, a group obtained by removing (n ax1 +1) hydrogen atoms from a benzene ring, more preferably, a group obtained by removing (n ax1 +1) hydrogen atoms from a benzene ring, further preferably, a group obtained by removing (n ax1 +1) hydrogen atoms from a benzene ring.

[0452] Wa x1 The aromatic hydrocarbon group in Wa x1 may have a substituent or can not have a substituent, and is preferably not have a substituent. As the substituent, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and the like can be exemplified. As the alkyl group, the alkoxy group, the halogen atom, and the halogenated alkyl group of the substituent, the same groups as those exemplified as the substituent of the cyclic aliphatic hydrocarbon group in Ya x1 is a group obtained by removing (n ax1 +1) hydrogen atoms from an aromatic ring, the substituent is a group that substitutes a hydrogen atom in the group obtained by removing (n ax1 +1) hydrogen atoms from the aromatic ring. 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, further preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

[0453] 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, further preferably 1, 2, or 3, and particularly preferably 1 or 2. Among them, n ax1 is preferably 1.

[0454] Specific examples of the structural unit (a10) represented by the formula (a10-1) are shown below.

[0455] In each of the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0456] [Chem. 43]

[0457]

[0458] [Chem. 44]

[0459]

[0460] [Chem. 45]

[0461]

[0462] [Chemical Formula 46]

[0463]

[0464] The structural unit (a10) possessed by the (Al) component can be one or two or more.

[0465] In the case where the (Al) component has the structural unit (a10), the proportion of the structural unit (a10) in the (Al) component is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, and further preferably 10 to 30 mol%, relative to the total (100 mol%) of all the structural units constituting the (Al) component.

[0466] By setting the proportion of the structural unit (a10) to be the lower limit value or more, it is easier to improve the sensitivity. On the other hand, by making it the upper limit value or less, it is easier to achieve a balance with other structural units.

[0467] Regarding the structural unit (st):

[0468] The structural unit (st) is a structural unit derived from styrene or a styrene derivative. The "structural unit derived from styrene" means a structural unit constituted by cleavage of the olefinic double bond of styrene. The "structural unit derived from a styrene derivative" means a structural unit constituted by cleavage of the olefinic double bond of a styrene derivative.

[0469] The "styrene derivative" means a compound in which at least one hydrogen atom of styrene is substituted with a substituent. As the styrene derivative, for example, a compound in which the hydrogen atom at the α-position of styrene is substituted with a substituent, a compound in which one or more hydrogen atoms of the benzene ring of styrene is substituted with a substituent, a compound in which the hydrogen atom at the α-position of styrene and one or more hydrogen atoms of the benzene ring of styrene are substituted with a substituent, and the like can be exemplified.

[0470] As the substituent which substitutes the hydrogen atom at the α-position of styrene, an alkyl group having a carbon number of 1 to 5 or a halogenated alkyl group having a carbon number of 1 to 5 can be exemplified.

[0471] As the alkyl group having a carbon number of 1 to 5, a linear or branched alkyl group having a carbon number of 1 to 5 is preferable, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and the like can be exemplified.

[0472] The halogenated alkyl group having a carbon number of 1 to 5 is a group in which part or all of the hydrogen atoms of the alkyl group having a carbon number of 1 to 5 are substituted with a halogen atom. As the halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like can be exemplified, and a fluorine atom is particularly preferable.

[0473] As the substituent of the hydrogen atom at the α-position of the substituted styrene, an alkyl group having 1 to 5 carbon atoms or a fluoroalkyl group having 1 to 5 carbon atoms is preferred, an alkyl group having 1 to 3 carbon atoms or a fluoroalkyl group having 1 to 3 carbon atoms is more preferred, and a methyl group is further preferred from the viewpoint of industrial availability.

[0474] As the substituent of the hydrogen atom of the benzene ring of the substituted styrene, an alkyl group, an alkoxy group, a halogen atom, a haloalkyl group, or the like can be exemplified.

[0475] As the alkyl group of the substituent, an alkyl group having 1 to 5 carbon atoms is preferred, and a methyl group, an ethyl group, a propyl group, an n-butyl group, or a t-butyl group is more preferred.

[0476] As the alkoxy group of the substituent, an alkoxy group having 1 to 5 carbon atoms is preferred, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a t-butoxy group is more preferred, and a methoxy group or an ethoxy group is further preferred.

[0477] As the halogen atom of the substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, or the like can be exemplified, and a fluorine atom is preferred.

[0478] As the haloalkyl group of the substituent, a group in which a part or all of the hydrogen atoms of the alkyl group are substituted with the halogen atom can be exemplified.

[0479] As the substituent of the hydrogen atom of the benzene ring of the substituted styrene, an alkyl group having 1 to 5 carbon atoms is preferred, a methyl group or an ethyl group is more preferred, and a methyl group is further preferred.

[0480] As the structural unit (st), a structural unit derived from a styrene, or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of the styrene is substituted with an alkyl group having 1 to 5 carbon atoms or a haloalkyl group having 1 to 5 carbon atoms is preferred, a structural unit derived from a styrene or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of the styrene is substituted with a methyl group is more preferred, and a structural unit derived from a styrene is further preferred.

[0481] The structural unit (st) possessed by the (Al) component can be one or two or more.

[0482] In the case where the (Al) component has the structural unit (st), the proportion of the structural unit (st) is preferably 1 to 30 mol%, and more preferably 3 to 20 mol%, relative to the total (100 mol%) of all the structural units constituting the (Al) component.

[0483] The (Al) component contained in the resist composition can be used alone or two or more can be used in combination.

[0484] In the resist composition of the present embodiment, the (Al) component can exemplify a high molecular compound having a repeating structure of structural unit (al).

[0485] As a preferred (Al) component, a high molecular compound having a repeating structure of structural unit (al) and other structural unit can be exemplified. As the other structural unit, structural unit (a10) or structural unit (st) or the like can be exemplified.

[0486] In addition to the combination of the above 2 kinds of structural units, the above-described structural units can be further combined as a third or 3 or more kinds of structural units as appropriate to meet a desired effect. As a combination of 3 or more kinds of structural units, a combination of structural unit (al) and structural unit (a10) and structural unit (st) or the like can be exemplified.

[0487] As a preferred example of the (Al) component, a high molecular compound having a repeating structure of structural unit (al) and structural unit (a10); a high molecular compound having a repeating structure of structural unit (al) and structural unit (st); a high molecular compound having a repeating structure of structural unit (al), structural unit (a10) and structural unit (st) can be exemplified.

[0488] The (Al) component can be produced by dissolving monomers from which the respective structural units are derived in a polymerization solvent, to which a radical polymerization initiator such as azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (e.g., V-601 or the like) or the like is added, and performing polymerization.

[0489] Alternatively, the (Al) component can be produced by dissolving monomers from which structural unit (al) is derived and monomers from which structural units other than structural unit (al) are derived as necessary in a polymerization solvent, adding a radical polymerization initiator as described above, and performing polymerization, followed by a deprotection reaction.

[0490] Further, at the time of polymerization, a chain transfer agent such as HS-CH2-CH2-CH2-C(CF3)2-OH can be used in combination, whereby a -C(CF3)2-OH group can be introduced at the terminal. A copolymer of a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom is effective for reduction of development defects and reduction of LER (line edge roughness: unevenness of the line side wall).

[0491] The weight average molecular weight (Mw) of the (Al) component (polystyrene conversion basis based on gel permeation chromatography (GPC)) is not particularly limited, and is preferably 1000 to 50000, more preferably 2000 to 30000, and further preferably 3000 to 20000.

[0492] If the Mw of the (Al) component is below the preferable upper limit of the range, sufficient solubility against a resist solvent is obtained for use as a resist, and if it is above the preferable lower limit of the range, dry etching resistance and a good resist pattern cross-sectional shape are obtained.

[0493] The molecular weight distribution coefficient (Mw / Mn) of the (Al) component is not particularly limited, and is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and particularly preferably 1.0 to 2.0. In addition, Mn represents the number average molecular weight.

[0494] • Base material component other than the (Al) component

[0495] In the resist composition of the present embodiment, as the (A) component, a base material component other than the (Al) component, which changes in solubility to a developer due to the action of an acid, can be used in combination. As the base material component other than the (Al) component, there is no particular limitation, and any of a variety of compounds known as a base material component for a chemically amplified resist composition in the past can be arbitrarily selected and used, and one kind of a high molecular compound or a low molecular compound can be used alone, or two or more kinds can be used in combination.

[0496] The proportion of the (Al) component in the (A) component with respect to the total mass of the (A) component is preferably 25% by mass or more, more preferably 50% by mass or more, and further preferably 75% by mass or more, and can be 100% by mass. If the proportion is 25% by mass or more, it becomes easy to form a resist pattern excellent in various lithography properties.

[0497] In the resist composition of the present embodiment, the content of the (A) component with respect to the total mass (100% by mass) of the resist composition is preferably 20% by mass or more. By making the content of the (A) component 20% by mass or more, it becomes easy to form a resist film of a thick film (for example, 5 μm or more in film thickness). The upper limit of the content of the (A) component is not particularly limited as long as it is a concentration at which a resist film can be formed, and for example, it can be 50% by mass or less. The content of the (A) component is preferably 20 to 50% by mass, more preferably 22 to 50% by mass, and further preferably 25 to 50% by mass.

[0498] (Z) component

[0499] The (Z) component is a polyether compound having a weight average molecular weight of 400 or more.

[0500] In the present specification, the "polyether compound" refers to a high molecular compound containing a plurality of ether bonds (-O-) in the main chain. As the (Z) component, a high molecular compound having a structural unit (zl) represented by the following general formula (zl-1) can be exemplified.

[0501] [Chem. 47]

[0502]

[0503] (In the formula, Rz 1 represents a divalent hydrocarbon group which can have a substituent.]

[0504] In General Formula (z1-1), Rz 1 represents a divalent hydrocarbon group which can have a substituent. The hydrocarbon group preferably has a carbon number of 1 to 15, more preferably a carbon number of 1 to 10, and further preferably a carbon number of 1 to 6. The hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and is preferably an aliphatic hydrocarbon group. The aliphatic hydrocarbon group can be saturated or unsaturated, and is preferably saturated. As the aliphatic hydrocarbon group, there can be mentioned a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group having a ring in the structure. Rz 1 is preferably a linear or branched aliphatic hydrocarbon group.

[0505] Rz 1 The linear or branched aliphatic hydrocarbon group in Rz

[0506] The linear alkylene group preferably has a carbon number of 1 to 10, more preferably a carbon number of 1 to 6, further preferably a carbon number of 1 to 4, and particularly preferably a carbon number of 2 or 3. As a specific example of the linear alkylene group, there can be mentioned a methylene group [-CH2-], an ethylene group [- (CH2)2-], a propylene group [- (CH2)3-], a butylene group [- (CH2)4-], a pentylene group [- (CH2)5-], and the like.

[0507] The number of carbons of the branched alkylene group is preferably from 2 to 10, more preferably from 3 to 6, further preferably 3 or 4, and particularly preferably 3. As specific examples of the branched alkylene group, there can be mentioned alkyl methylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-, and the like; alkyl ethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-, and the like; alkyl propylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-, and the like; alkyl butylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2-, and the like; and the like. The number of carbons of the alkyl group in the alkyl alkylene group is preferably from 1 to 5, more preferably from 1 to 3, further preferably 1 or 2, and particularly preferably 1. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group.

[0508] Rz 1 The divalent hydrocarbon group in Rz 1 The divalent hydrocarbon group in Rz

[0509] The divalent hydrocarbon group in Rz 1 is preferably a vinyl group (-CH2CH2-) or a methyl ethylene group [-CH(CH3)CH2-].

[0510] The structural unit (z1) possessed by the (Z) component can be one or two or more. The structural unit (z1) preferably has an oxyalkylene skeleton, and more preferably consists of an oxyalkylene skeleton. As a preferable specific example of the structural unit (z1), there can be mentioned a structural unit consisting of an oxyethylene group (-CH2CH2O-); a structural unit consisting of an oxypropylene group [-CH(CH3)CH2O-]; and the like.

[0511] As a preferable example of the (Z) component, there can be mentioned a high-molecular-weight compound (Z1-2) represented by the following general formula (z1-2).

[0512] [Formula 48]

[0513]

[0514] [In the formula, Rz 11 represents a divalent hydrocarbon group which can have a substituent. nz represents an integer of two or more.11 may be the same or different. Rz 12 and Rz 13 each independently represents a hydrogen atom, an alkyl group, an alkoxy group, an amino group or a mercapto group.

[0515] In the general formula (z1-2), Rz 11 represents a divalent hydrocarbon group which can have a substituent. As the divalent hydrocarbon group in Rz 11 , the same hydrocarbon group as exemplified in Rz 1 in the general formula (z1) can be exemplified. Rz 11 More preferably, it is a linear or branched alkylene group having a carbon number of 1 to 10, more preferably a linear or branched alkylene group having a carbon number of 1 to 6, further preferably a linear or branched alkylene group having a carbon number of 2 to 4, and particularly preferably a vinyl group or a methylvinyl group.

[0516] Rz 11 may be the same or different.

[0517] In the general formula (z1-2), nz represents an integer of 2 or more. nz is preferably a number which makes the weight average molecular weight of the high molecular compound (Z1-2) 400 or more, and can vary depending on the kind of Rz 11 . For example, in the case where Rz 11 is a vinyl group (-CH2CH2-), nz is preferably an integer of 9 or more, and more preferably an integer of 20 or more. For example, in the case where Rz 11 is a methylvinyl group [-CH(CH3)CH2-], nz is preferably an integer of 7 or more, and more preferably an integer of 15 or more. The upper limit of nz is not particularly limited, and for example, an integer of 1000 or less, 700 or less, 500 or less, or 400 or less can be exemplified.

[0518] In the general formula (z1-2), Rz 12 and Rz 13 each independently represents a hydrogen atom, an alkyl group, an alkoxy group, an amino group or a mercapto group. The carbon number of the alkyl group and the alkoxy group is preferably 1 to 10, more preferably a carbon number of 1 to 6, further preferably a carbon number of 1 to 3, and particularly preferably a carbon number of 1 or 2. The alkyl group can be branched or linear, and is preferably linear. The alkyl group possessed by the alkoxy group can be branched or linear, and is preferably linear.

[0519] Rz 12 and Rz 13 are preferably hydrogen atoms.

[0520] As a preferred specific example of the (Z) component, a polyalkylene glycol such as polyethylene glycol, polypropylene glycol and the like, and a derivative thereof can be exemplified.

[0521] As the (Z) component, polyethylene glycol or polypropylene glycol is preferred.

[0522] The weight average molecular weight (Mw) of the (Z) component (polystyrene conversion basis based on gel permeation chromatography) is 400 or greater. By making the weight average molecular weight of the (Z) component 400 or greater, the generation of cracks at the time of resist pattern formation can be suppressed. The Mw of the (Z) component is preferably 500 or greater, more preferably 700 or greater, further preferably 800 or greater, and particularly preferably 1000 or greater. The upper limit of the Mw of the (Z) component is not particularly limited, and is preferably 30000 or less, more preferably 25000 or less, and further preferably 20000 or less. As the range of the Mw of the (Z) component, for example, 400 to 30000, 500 to 30000, 700 to 30000, 800 to 30000, or 1000 to 30000, etc. can be exemplified.

[0523] In the resist composition of the present embodiment, the (Z) component can be used alone or two or more kinds can be used in combination.

[0524] In the resist composition of the present embodiment, the content of the (Z) component is 0.8 to 32 parts by mass with respect to 100 parts by mass of the (A) component. By making the content of the (Z) component the lower limit value of the range or greater, the generation of cracks at the time of resist pattern formation can be suppressed. Furthermore, by making the content of the (Z) component the upper limit value of the range or less, the resolution at the time of resist pattern formation is good. The content of the (Z) component is preferably 0.8 to 30 parts by mass, more preferably 1.0 to 25 parts by mass, further preferably 1.5 to 20 parts by mass, and particularly preferably 2.0 to 15 parts by mass with respect to 100 parts by mass of the (A) component.

[0525] <Other Components>

[0526] The resist composition of the present embodiment can further contain other components in addition to the (A) component and the (Z) component. As the other components, for example, the (B) component, the (D) component, the (E) component, the (F) component, the (S) component, etc. shown below can be exemplified.

[0527] <Acid Generator Component (B)

[0528] The resist composition of the present embodiment can further contain, in addition to the (A) component and the (Z) component, an acid generator component (B) (hereinafter referred to as “(B) component”) that generates an acid by exposure.

[0529] The (B) component is not particularly limited, and an acid generator that has been proposed so far as an acid generator for a chemically amplified resist composition can be used.

[0530] As such an acid generator, onium salt-based acid generators such as iodonium salts, sulfonium salts, and the like; sulfonic acid oxime ester-based acid generators; diazomethane-based acid generators such as bisalkyl or bisaryl sulfonyl diazomethane, poly(bis sulfonyl) diazomethane, and the like; nitrobenzyl sulfonic acid salt-based acid generators; imino sulfonic acid salt-based acid generators; disulfone-based acid generators; and the like can be exemplified.

[0531] As the (B) component, a compound (B1) consisting of an onium salt (hereinafter referred to as "(B1) component") is preferably contained.

[0532] • (B1) component

[0533] As the (B1) component, for example, a compound represented by general formula (b-1) (hereinafter also referred to as "(b-1) component"), a compound represented by general formula (b-2) (hereinafter also referred to as "(b-2) component"), or a compound represented by general formula (b-3) (hereinafter also referred to as "(b-3) component") described below can be exemplified.

[0534] [Chemical Formula 49]

[0535]

[0536] [Note that, in the formulae, R 101 and R 104 ~R 108 are each independently a cyclic group which can have a substituent, a chain alkyl group which can have a substituent, or a chain alkenyl group which can have a substituent. R 104 and R 105 may be bonded to each other to form a ring structure. R 102 is a fluoroalkyl group having a carbon number of 1 to 5 or a fluorine atom. Y 101 is a divalent linking group containing an oxygen atom or a single bond. V 101 ~V 103 are each independently a single bond, an alkylene group, or a fluoroalkylene group. L 101 ~L 102 are each independently a single bond or an oxygen atom. L 103 ~L 105 are each independently a single bond, -CO-, or -SO2-. m is an integer of 1 or more, and M m+ is an onium cation having a valence of m.

[0537] {anion part}

[0538] • anion in (b-1) component

[0539] In formula (b-1), R 101 is a cyclic group which can have a substituent, a chain alkyl group which can have a substituent, or a chain alkenyl group which can have a substituent.

[0540] The cyclic group can have a substituent group:

[0541] The cyclic group is preferably a cyclic hydrocarbon group. The cyclic hydrocarbon group can be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group indicates a hydrocarbon group that does not have aromaticity. In addition, the aliphatic hydrocarbon group can be saturated or unsaturated, and is usually preferably saturated.

[0542] R 101 The aromatic hydrocarbon group in R is a hydrocarbon group having an aromatic ring. The number of carbons of 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. Among the number of carbons, the number of carbons in the substituent group is not included.

[0543] As the aromatic ring possessed by the aromatic hydrocarbon group in R 101 , specifically, a benzene ring, a fluorene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a biphenyl ring, or an aromatic heterocycle in which a part of carbon atoms constituting these aromatic rings is substituted with a hetero atom, etc. can be exemplified. As the hetero atom in the aromatic heterocycle, an oxygen atom, a sulfur atom, a nitrogen atom, etc. can be exemplified.

[0544] As the aromatic hydrocarbon group in R 101 , specifically, a group in which one hydrogen atom is removed from the aromatic ring (an aryl group such as a phenyl group, a naphthyl group, etc.), a group in which one hydrogen atom of the aromatic ring is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc., an aralkyl group, etc.) can be exemplified. The number of carbons of the alkylene group (alkyl chain in the aralkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0545] R 101 The cyclic aliphatic hydrocarbon group in R can exemplify a cyclic aliphatic hydrocarbon group having a ring in the structure.

[0546] As the cyclic aliphatic hydrocarbon group having a ring in the structure, a cycloaliphatic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring), a group in which a cycloaliphatic hydrocarbon group is bonded to the end of a straight-chain or branched-chain aliphatic hydrocarbon group, a group in which a cycloaliphatic hydrocarbon group is interposed in a straight-chain or branched-chain aliphatic hydrocarbon group, etc. can be exemplified.

[0547] The number of carbons of the cycloaliphatic hydrocarbon group is preferably 3 to 20, and more preferably 3 to 12.

[0548] The alicyclic hydrocarbon group can 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 monocyclic alkane is preferable. As the monocyclic alkane, a monocyclic alkane having 3 to 6 carbons is preferable, and specifically, cyclopentane, cyclohexane, and the like can be exemplified. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycyclic alkane is preferable, and as the polycyclic alkane, a polycyclic alkane having 7 to 30 carbons is preferable. Among them, a polycyclic alkane having a polycyclic skeleton of a cross-linked ring group such as adamantyl, norbornyl, isobornyl, tricyclodecanyl, tetracyclododecanyl, and the like; a polycyclic alkane having a polycyclic skeleton of a fused ring group such as a steroid skeleton-containing cyclic group is more preferable.

[0549] Among them, as the cyclic aliphatic hydrocarbon group in R 101 , a group obtained by removing one or more hydrogen atoms from a monocyclic alkane or a polycyclic alkane is preferable, a group obtained by removing one hydrogen atom from a polycyclic alkane is more preferable, and adamantyl, norbornyl, and most preferably adamantyl are particularly preferable.

[0550] The number of carbons of the straight-chain aliphatic hydrocarbon group which can be bonded to the alicyclic hydrocarbon group is preferably 1 to 10, more preferably 1 to 6, further preferably 1 to 4, and most preferably 1 to 3. As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferable, and specifically, methylene [-CH2-], ethylene [- (CH2)2-], propylene [- (CH2)3-], butylene [- (CH2)4-], pentylene [- (CH2)5-], and the like can be exemplified.

[0551] The number of carbons of the branched aliphatic hydrocarbon group which can be bonded to the alicyclic hydrocarbon group is preferably 2 to 10, more preferably 3 to 6, further preferably 3 or 4, and most preferably 3. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, alkylmethylene such as -CH (CH3) -, -CH (CH2CH3) -, -C (CH3) 2-, -C (CH3) (CH2CH3) -, -C (CH3) (CH2CH2CH3) -, -C (CH2CH3) 2-, and the like; alkylethylene such as -CH (CH3) CH2-, -CH (CH3) CH (CH3) -, -C (CH3) 2CH2-, -CH (CH2CH3) CH2-, -C (CH2CH3) 2CH2-, and the like; alkylpropylene such as -CH (CH3) CH2CH2-, -CH2CH (CH3) CH2-, and the like; alkylbutylene such as -CH (CH3) CH2CH2CH2-, -CH2CH (CH3) CH2CH2-, and the like; and the like can be exemplified. As the alkyl group in the alkylalkylene group, a straight-chain alkyl group having 1 to 5 carbons is preferable.

[0552] Further, R 101The cyclic hydrocarbon group in the formula can contain heteroatoms, just like heterocycles. Specifically, examples include lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), -SO2-containing cyclic groups represented by the general formulas (a5-r-1) to (a5-r-4), and other heterocyclic groups represented by the following chemical formulas (r-hr-1) to (r-hr-16).

[0553] [Transformation 50]

[0554]

[0555] As R 101 Substituents in the cyclic group can include, for example, alkyl, alkoxy, halogen atom, haloalkyl, hydroxy, carbonyl, nitro, etc. The alkyl group used as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably methyl, ethyl, propyl, n-butyl, or tert-butyl.

[0556] The alkoxy group used as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, or tert-butoxy, and most preferably methoxy or ethoxy.

[0557] Examples of halogen atoms that can be used as substituents include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being the preferred option.

[0558] Examples of alkyl halogens that can be used as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, tert-butyl, etc., in which some or all of the hydrogen atoms are replaced by the halogen atom.

[0559] The carbonyl group, as a substituent, is a group that replaces the methylene (-CH2-) group that constitutes the cyclic hydrocarbon group.

[0560] Chain alkyl groups that may have substituents:

[0561] As R 101 The chain alkyl group can be either straight-chain or branched.

[0562] As a straight-chain alkyl group, it is preferably composed of 1 to 20 carbon atoms, more preferably 1 to 15, and most preferably 1 to 10. Specifically, examples include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, isotriadecyl, tetradecyl, pentadecyl, hexadecyl, isohexadecanyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, dodecyl, and dodecyl.

[0563] As the branched alkyl group, the number of carbon atoms is preferably from 3 to 20, more preferably from 3 to 15, and most preferably from 3 to 10. Specifically, for example, 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, and the like can be mentioned.

[0564] The chain alkenyl group which can have a substituent:

[0565] As the chain alkenyl group of R 101 , either of a straight chain or a branched chain can be mentioned, and the number of carbon atoms is preferably from 2 to 10, more preferably from 2 to 5, further preferably from 2 to 4, and particularly preferably 3. As the straight chain alkenyl group, for example, vinyl, propenyl (allyl), butynyl, and the like can be mentioned. As the branched chain alkenyl group, for example, 1-methylethenyl, 2-methylethenyl, 1-methylpropenyl, 2-methylpropenyl, and the like can be mentioned.

[0566] As the chain alkenyl group, among the above, a straight chain alkenyl group is preferred, and more preferably vinyl, propenyl, and particularly preferably vinyl.

[0567] As the substituent in the chain alkyl group or the chain alkenyl group of R 101 , for example, alkoxy, a halogen atom, a halogenated alkyl group, hydroxy, carbonyl, nitro, amino, a cyclic group of R 101 , and the like can be mentioned.

[0568] Among the above, R 101 is preferably a cyclic group which can have a substituent, and more preferably a cyclic hydrocarbon group which can have a substituent. More specifically, a group obtained by removing one or more hydrogen atoms from a phenyl group, a naphthyl group, a polycyclic alkane; a lactone-containing cyclic group represented by the general formulae (a2-r-1) to (a2-r-7); a -SO2- containing cyclic group represented by the general formulae (a5-r-1) to (a5-r-4); and the like are preferred.

[0569] In the formula (b-1), Y 101 is a single bond or a divalent linking group containing an oxygen atom.

[0570] In the case where Y 101 is a divalent linking group containing an oxygen atom, this Y 101 may contain atoms other than an oxygen atom. As the atoms other than an oxygen atom, for example, a carbon atom, a hydrogen atom, a sulfur atom, a nitrogen atom, and the like can be mentioned.

[0571] As the divalent linking group containing an oxygen atom, for example, there can be mentioned an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), an oxy carbonyl group (-O-C(=O)-), an amide bond (-C(=O)-NH-), a carbonyl group (-C(=O)-), a carbonate bond (-O-C(=O)-O-), and the like non-hydrocarbon-containing oxygen atom-containing linking group; a combination of the non-hydrocarbon-containing oxygen atom-containing linking group with an alkylene group, and the like. In the combination, a sulfonyl group (-SO2-) can be further linked. As the above-mentioned divalent linking group containing an oxygen atom, for example, there can be mentioned a linking group represented by the following general formulae (y-al-1) to (y-al-7), respectively.

[0572] [Formula 51]

[0573]

[0574] [In the formula, V' 101 is a single bond or an alkylene group having a carbon number of 1 to 5, V' 102 is a divalent saturated hydrocarbon group having a carbon number of 1 to 30.]

[0575] V' 102 The divalent saturated hydrocarbon group in V' is preferably an alkylene group having a carbon number of 1 to 30, more preferably an alkylene group having a carbon number of 1 to 10, and further preferably an alkylene group having a carbon number of 1 to 5.

[0576] As the alkylene group in V' 101 and V' 102 , there can be mentioned a linear alkylene group and a branched alkylene group, and a linear alkylene group is preferred.

[0577] As the alkylene group in V' 101 and V' 102 , specifically, there can be mentioned a methylene group [-CH2-]; alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-, and the like; an ethylene group [-CH2CH2-]; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and the like; a propylene group (n-propylene group) [-CH2CH2CH2-]; alkylpropylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-, and the like; a butylene group [-CH2CH2CH2CH2-]; alkylbutylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2-, and the like; and a pentylene group [-CH2CH2CH2CH2CH2-] and the like.

[0578] Further, V 101 or V 102 In the alkylene group in V 3 , one methylene group can be replaced with a bivalent aliphatic cyclic group having 5 to 10 carbons. The aliphatic cyclic group is preferably a bivalent group obtained by further removing one hydrogen atom from a cyclic aliphatic hydrocarbon group (monocyclic aliphatic hydrocarbon group, polycyclic aliphatic hydrocarbon group) of Ra 3 in the formula (al-r-l) above, and more preferably cyclohexylene, 1,5-adamantylene or 2,6-adamantylene.

[0579] As Y 101 , a bivalent linking group containing an ester bond, or a bivalent linking group containing an ether bond is preferable, and a linking group represented by the formula (y-al-l) to (y-al-5) above, respectively, is more preferable.

[0580] In the formula (b-l), V 101 is a single bond, an alkylene group or a fluoroalkylene group. The alkylene group, fluoroalkylene group in V 101 preferably has 1 to 4 carbons. As the fluoroalkylene group in V 101 , a group in which part or all of the hydrogen atoms of the alkylene group in V 101 are replaced with fluorine atoms can be exemplified. Among them, V 101 is preferably a single bond or a fluoroalkylene group having 1 to 4 carbons.

[0581] In the formula (b-l), R 102 is a fluorine atom or a fluoroalkyl group having 1 to 5 carbons. R 102 is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbons, and more preferably a fluorine atom.

[0582] As a specific example of the anion portion represented by the formula (b-l), for example, in the case where Y 101 is a single bond, a fluoroalkylsulfonate anion such as trifluoromethane sulfonate anion or perfluorobutane sulfonate anion can be exemplified; in the case where Y 101 is a bivalent linking group containing an oxygen atom, an anion represented by any one of the following formulas (an-l) to (an-3) can be exemplified.

[0583] [Chemical Formula 52]

[0584]

[0585] [In the formula, R 101 is an aliphatic cyclic group which can have a substituent, a monovalent heterocyclic group represented by the above chemical formula (r-hr-l) to (r-hr-6), respectively, or a chain alkyl group which can have a substituent. R 102It can be an aliphatic cyclic group that may have substituents, a lactone-containing cyclic group represented by the general formulas (a2-r-1), (a2-r-3) to (a2-r-7), or a -SO2-containing cyclic group represented by the general formulas (a5-r-1) to (a5-r-4). R” 103 It can be an aromatic cyclic group that may have substituents, an aliphatic cyclic group that may have substituents, or a chain-like alkenyl group that may have substituents. V” 101 It is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluoroalkylene group having 1 to 4 carbon atoms. R 102 It is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms. v” is an independent integer from 0 to 3, q” is an independent integer from 0 to 20, and n” is 0 or 1.

[0586] R” 101 、R” 102 And R” 103 The aliphatic cyclic group that may have substituents is preferably R in formula (b-1). 101 The group exemplified is a cyclic aliphatic hydrocarbon group. Examples of substituents include those related to R in formula (b-1). 101 The substituents in the substituted cyclic aliphatic hydrocarbon group are the same groups.

[0587] R” 103 The aromatic cyclic group that may have substituents is preferably R in formula (b-1). 101 The group exemplified is the aromatic hydrocarbon group in the cyclic hydrocarbon group. Examples of substituents include those corresponding to R in formula (b-1). 101 The same substituents that can replace the aromatic hydrocarbon group in the group.

[0588] R” 101 The substituted chain alkyl group is preferably R in formula (b-1). 101 The chain alkyl group is exemplified by the group.

[0589] R” 103 The chain alkenyl group that may have substituents is preferably R in formula (b-1). 101 The chain-like alkenyl group is exemplified by the group.

[0590] Anions in component (b-2)

[0591] In equation (b-2), R 104 R 105 Each can be independently a cyclic group that may have substituents, a chain-like alkyl group that may have substituents, or a chain-like alkenyl group that may have substituents, and examples can be given for R in formula (b-1). 101 Same group. Wherein, R104 R 105 They can bond together to form a ring.

[0592] R 104 R 105 Preferably, it is a chain alkyl group that may have substituents, more preferably a straight-chain or branched alkyl group, or a straight-chain or branched fluoroalkyl group.

[0593] The chain-like 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. For reasons such as good solubility in solvents used as corrosion inhibitors, R... 104 R 105 The number of carbon atoms in the chain alkyl group is preferably as small as possible within the aforementioned range. Furthermore, R... 104 R 105 In the chain alkyl group, the more hydrogen atoms replaced by fluorine atoms, the stronger the acid and the better the transparency to high-energy light and electron beams below 250 nm, which is therefore preferred. The proportion of fluorine atoms in the chain alkyl group, i.e., the fluorination rate, is preferably 70-100%, more preferably 90-100%, and most preferably a perfluoroalkyl group in which all hydrogen atoms are replaced by fluorine atoms.

[0594] In equation (b-2), V 102 V 103 Each can be independently a single bond, an alkylene group, or a fluoroalkylene group, and examples can be given for V in formula (b-1). 101 Same group.

[0595] In equation (b-2), L 101 L 102 Each can be a single bond or an oxygen atom, independently.

[0596] Anions in component (b-3)

[0597] In equation (b-3), R 106 ~R 108 Each can be independently a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents, and examples can be given for R in formula (b-1). 101 Same group.

[0598] In equation (b-3), L 103 ~L 105 Each can be a single bond, -CO-, or -SO2-, respectively.

[0599] Among the above, the anion in the component (B) is preferably the anion in the component (b-1). Among them, more preferably, it is a fluoroalkylsulfonate anion or an anion represented by any one of the above general formulae (an-1) to (an-3), and further preferably, it is a fluoroalkylsulfonate anion or an anion represented by any one of the general formulae (an-1) and (an-2).

[0600] {Cationic portion}

[0601] In the formula (b-1), the formula (b-2), and the formula (b-3), M m+ represents an m-valent onium cation. Among them, preferably, it is a sulfonium cation or an iodonium cation.

[0602] m is an integer of 1 or more.

[0603] As the preferred cationic portion ((M m+ ) 1 / m ), an organic cation represented by any one of the following general formulae (ca-1) to (ca-4) can be exemplified.

[0604] [Chemical Formula 53]

[0605]

[0606] [In the formula, R 201 to R 207 , and R 211 to R 212 independently represent an aryl group, an alkyl group, or an alkenyl group which can have a substituent. R 201 to R 203 , R 206 to R 207 , R 211 to R 212 may be bonded to each other to form a ring together with the sulfur atom in the formula. R 208 to R 209 independently represent a hydrogen atom or an alkyl group having a carbon number of 1 to 5. R 210 is an aryl group which can have a substituent, an alkyl group which can have a substituent, an alkenyl group which can have a substituent, or a cyclic group containing -SO2- which can have a substituent. L 201 represents -C(=O)- or -C(=O)-O-. Y 201 independently represent an arylene group, an alkylene group, or an alkenylene group. x is 1 or 2. W 201 represents a (x+1)-valent linking group.

[0607] In the above general formulae (ca-1) to (ca-4), R 201 to R 207 , and R 211 to R 212The aryl group in the aryl group can be exemplified by unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred.

[0608] As R 201 ~R 207 and R 211 ~R 212 The alkyl group in the alkyl group is preferably a chain-like or cyclic alkyl group with 1 to 30 carbon atoms.

[0609] As R 201 ~R 207 and R 211 ~R 212 The alkenyl group in the alkenyl group preferably has 2 to 10 carbon atoms.

[0610] As R 201 ~R 207 and R 210 ~R 212 The substituents that may be present include, for example, alkyl, halogen atom, haloalkyl, carbonyl, cyano, amino, aryl, and groups represented by the following general formulas (ca-r-1) to (ca-r-7).

[0611] [Chemistry 54]

[0612]

[0613] [In the formula, R'] 201 Each group can be an independent hydrogen atom, a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents.

[0614] Cyclic groups that may have substituents:

[0615] The cyclic group is preferably a cyclic hydrocarbon group, which can be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group indicates a hydrocarbon group that is not aromatic. Furthermore, the aliphatic hydrocarbon group can be saturated or unsaturated, but is generally preferred to be saturated.

[0616] R' 201 The aromatic hydrocarbon group in the form is a hydrocarbon group having an aromatic ring. The number of carbon atoms in this aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. This number of carbon atoms does not include the carbon atoms in the substituents.

[0617] As R' 201The aromatic hydrocarbon group in the above-mentioned aromatic hydrocarbon group-containing group preferably has an aromatic ring. Specifically, examples of the aromatic ring include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and an aromatic heterocycle in which a part of the carbon atoms constituting the aromatic 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.

[0618] R' in the above-mentioned R' is preferably a hydrogen atom, a linear or branched aliphatic hydrocarbon group, a cyclic aliphatic hydrocarbon group, or an aromatic hydrocarbon group. 201 The aromatic hydrocarbon group in the above-mentioned aromatic hydrocarbon group-containing group preferably has an aromatic ring. Specifically, examples of the aromatic ring include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and an aromatic heterocycle in which a part of the carbon atoms constituting the aromatic 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.

[0619] R' in the above-mentioned R' is preferably a hydrogen atom, a linear or branched aliphatic hydrocarbon group, a cyclic aliphatic hydrocarbon group, or an aromatic hydrocarbon group. 201 The cyclic aliphatic hydrocarbon group in the above-mentioned cyclic aliphatic hydrocarbon group-containing group is preferably an aliphatic hydrocarbon group having a ring in the structure.

[0620] The aliphatic hydrocarbon group having a ring in the structure is preferably an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an alicyclic hydrocarbon ring); a group obtained by bonding the terminal of a linear or branched aliphatic hydrocarbon group to an alicyclic hydrocarbon group; a group in which an alicyclic hydrocarbon group is interposed in a linear or branched aliphatic hydrocarbon group; or the like.

[0621] The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms.

[0622] The alicyclic hydrocarbon group can 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 monocyclic alkane is preferable. As the monocyclic alkane, a monocyclic alkane having 3 to 6 carbon atoms is preferable, and specifically, examples include cyclopentane, cyclohexane, and the like. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycyclic alkane is preferable, and as the polycyclic alkane, a polycyclic alkane having 7 to 30 carbon atoms is preferable. Among them, a polycyclic alkane having a cross-linked ring type polycyclic skeleton such as adamantyl, norbornyl, isobornyl, tricyclodecanyl, tetracyclododecanyl, and the like; a polycyclic alkane having a steroid skeleton type polycyclic skeleton such as a cyclic group having a fused ring type polycyclic skeleton are more preferable.

[0623] R' in the above-mentioned R' is preferably a hydrogen atom, a linear or branched aliphatic hydrocarbon group, a cyclic aliphatic hydrocarbon group, or an aromatic hydrocarbon group. 201 The cyclic aliphatic hydrocarbon group in the above-mentioned cyclic aliphatic hydrocarbon group-containing group is preferably a group obtained by removing one or more hydrogen atoms from a monocyclic alkane or a polycyclic alkane, and more preferably a group obtained by removing one hydrogen atom from a polycyclic alkane. Specifically, adamantyl, norbornyl, and the like are preferable, and adamantyl is most preferable.

[0624] The number of carbon atoms of the straight-chain or branched aliphatic hydrocarbon group which can be bonded to the alicyclic hydrocarbon group is preferably from 1 to 10, more preferably from 1 to 6, further preferably from 1 to 4, and particularly preferably from 1 to 3.

[0625] As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred, and specifically, methylene [-CH2-], ethylene [- (CH2)2-], propylene [- (CH2)3-], butylene [- (CH2)4-], pentylene [- (CH2)5-], and the like can be exemplified.

[0626] As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, alkylmethylene groups such as -CH (CH3)-, -CH (CH2CH3)-, -C (CH3)2-, -C (CH3) (CH2CH3)-, -C (CH3) (CH2CH2CH3)-, -C (CH2CH3)2-, and the like; alkylethylene groups such as -CH (CH3) CH2-, -CH (CH3) CH (CH3)-, -C (CH3)2CH2-, -CH (CH2CH3) CH2-, -C (CH2CH3)2CH2-, and the like; alkylpropylene groups such as -CH (CH3) CH2CH2-, -CH2CH (CH3) CH2-, and the like; alkylbutylene groups such as -CH (CH3) CH2CH2CH2-, -CH2CH (CH3) CH2CH2-, and the like; and the like can be exemplified. As the alkyl group in the alkylalkylene group, a straight-chain alkyl group having from 1 to 5 carbon atoms is preferred.

[0627] Further, R' 201 The cyclic hydrocarbon group in R'

[0628] As the substituent in the cyclic group of R' 201 , for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, and the like can be exemplified.

[0629] The alkyl group as the substituent is preferably an alkyl group having from 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, a t-butyl group.

[0630] The alkoxy group as the substituent is preferably an alkoxy group having from 1 to 5 carbon atoms, and more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a t-butoxy group, and most preferably a methoxy group, an ethoxy group.

[0631] Examples of halogen atoms that can be used as substituents include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being the preferred option.

[0632] Examples of alkyl halogens that can be used as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, tert-butyl, etc., in which some or all of the hydrogen atoms are replaced by the halogen atom.

[0633] The carbonyl group, as a substituent, is a group that replaces the methylene (-CH2-) group that constitutes the cyclic hydrocarbon group.

[0634] Chain alkyl groups that may have substituents:

[0635] As R' 201 The chain alkyl group can be either straight-chain or branched.

[0636] As a straight-chain alkyl group, it is preferred to have 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, examples include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, isotriadecyl, tetradecyl, pentadecyl, hexadecyl, isohexadecanyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, dodecyl, dodecyl, etc.

[0637] As a branched alkyl group, the number of carbon atoms is preferably 3 to 20, more preferably 3 to 15, and most preferably 3 to 10. Specifically, examples include 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl.

[0638] Chain alkenyl groups that may have substituents:

[0639] As R' 201 The chain-like alkenyl group can be either straight-chain or branched, preferably with 2 to 10 carbon atoms, more preferably with 2 to 5 carbon atoms, even more preferably with 2 to 4 carbon atoms, and particularly preferably with 3 carbon atoms. Examples of straight-chain alkenyl groups include vinyl, allyl, and butynyl. Examples of branched alkenyl groups include 1-methylvinyl, 2-methylvinyl, 1-methylpropenyl, and 2-methylpropenyl.

[0640] As a chain-like alkenyl group, the linear alkenyl group is preferred, more preferably vinyl or propenyl, and particularly preferably vinyl.

[0641] As R' 201The substituents in the chain alkyl group or chain alkenyl group, for example, can include an alkoxy group, a halogen atom, a haloalkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, the above-mentioned R 201 , and the like.

[0642] The R 201 , the chain alkyl group, or the chain alkenyl group can include, in addition to the above-mentioned groups, the same groups as the acid dissociable group represented by the above-mentioned formula (a1-r-2) as the ring group or the chain alkyl group.

[0643] wherein R 201 is preferably a ring group having a substituent, and more preferably a cyclic hydrocarbon group having a substituent. More specifically, for example, a group obtained by removing one or more hydrogen atoms from a phenyl group, a naphthyl group, or a polycyclic alkane; a lactone-containing ring group represented by the above-mentioned general formulas (a2-r-1) to (a2-r-7); a -SO2- containing ring group represented by the above-mentioned general formulas (a5-r-1) to (a5-r-4); and the like.

[0644] In the above-mentioned general formulas (ca-1) to (ca-4), in the case where R 201 to R 203 , R 206 to R 207 , R 211 to R 212 are bonded to each other to form a ring together with the sulfur atom in the formula, they can be bonded via a heteroatom such as a sulfur atom, an oxygen atom, a nitrogen atom, a carbonyl group, -SO-, -SO2-, -SO3-, -COO-, -CONH-, or -N(R N )-(the R N is an alkyl group having a carbon number of 1 to 5) and the like. As the formed ring, it is preferable that one ring including the sulfur atom in the ring skeleton of the ring is a three- to ten-membered ring including the sulfur atom, and particularly preferably a five- to seven-membered ring. As a specific example of the formed ring, for example, a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthrene ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring, and the like can be mentioned.

[0645] R 208 to R 209 each independently represent a hydrogen atom or an alkyl group having a carbon number of 1 to 5, and preferably a hydrogen atom or an alkyl group having a carbon number of 1 to 3. In the case where R 208 to R 209 are alkyl groups, they can be bonded to each other to form a ring.

[0646] R 210an optionally substituted aryl group, an optionally substituted alkyl group, an optionally substituted alkenyl group, or an optionally substituted SO2-containing cyclic group.

[0647] as the aryl group in R 210 The aryl group in R

[0648] as the aryl group in R 210 The alkyl group in R

[0649] as the alkenyl group in R 210 The alkenyl group in R 210 The SO2-containing cyclic group in R

[0650] Y 201 independently represents an arylene group, an alkylene group, or an alkenylene group.

[0651] Y 201 The arylene group in Y 101 The arylene group in Y

[0652] Y 201 The alkylene group in Y 101 The alkylene group in Y

[0653] In the formula (ca-4), x is 1 or 2.

[0654] W 201 is a linking group having a valence of (x+1), i.e., 2 or 3.

[0655] As the linking group having a valence of 2 in W 201 , an optionally substituted divalent hydrocarbon group can be exemplified, which is the same as Ya 21 in the above-mentioned general formula (a2-1). The divalent hydrocarbon group in W 201 may be any one of a linear, branched, or cyclic structure, and is preferably a cyclic structure. Among them, a group obtained by combining two carbonyl groups at both ends of an arylene group is preferred. As the arylene group, a phenylene group, a naphthylene group, or the like can be exemplified, and a phenylene group is particularly preferred.

[0656] As the linking group having a valence of 3 in W 201 , a group obtained by removing one hydrogen atom from the divalent hydrocarbon group in W 201a group obtained by removing one hydrogen atom from a divalent linking group in the formula (a-1), a group obtained by re-bonding the divalent linking group to the divalent linking group, and the like. As W 201 a trivalent linking group in the formula (a-1), preferably a group obtained by bonding two carbonyl groups to an arylene group.

[0657] As the preferred cation represented by the formula (ca-1), specifically, there can be mentioned cations represented by the following formulas (ca-1-1) to (ca-1-70), respectively.

[0658] [Chemical Formula 55]

[0659]

[0660] [Chemical Formula 56]

[0661]

[0662] [Chemical Formula 57]

[0663]

[0664] [In the formula, g1, g2, g3 represent the number of repetitions, 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.]

[0665] [Chemical Formula 58]

[0666]

[0667] [Chemical Formula 59]

[0668]

[0669] [Chemical Formula 60]

[0670]

[0671] [In the formula, R" 201 is a hydrogen atom or a substituent, and as the substituent, the same group as that exemplified as the substituent of R 201 to R 207 and R 210 to R 212 may have the same substituent as that exemplified as the substituent of R

[0672] As the preferred cation represented by the formula (ca-2), specifically, there can be mentioned diphenyliodonium cation, bis (4-tert-butylphenyl) iodonium cation, and the like.

[0673] As the preferred cation represented by the formula (ca-3), specifically, there can be mentioned cations represented by the following formulas (ca-3-1) to (ca-3-6), respectively.

[0674] [Chemical Formula 61]

[0675]

[0676] As the preferred cation represented by the formula (ca-4), specifically, there can be mentioned cations represented by the following formulas (ca-4-1) to (ca-4-2), respectively.

[0677] [Chemical Formula 62]

[0678]

[0679] Among the above, the cation portion ((M m+ ) 1 / m ) is preferably a cation represented by the general formula (ca-1). From the viewpoint of maintaining transparency in a thick resist film, in the general formula (ca-1), it is preferred that at least one of R 202 to R 203 be an alkyl group or an alkenyl group, more preferably that two or more of R 202 to R 203 be alkyl groups or alkenyl groups, and further preferably that two or more of R 202 to R 203 be alkyl groups. In the case where two or more of R 202 to R 203 are alkyl groups or alkenyl groups, these two groups can also be bonded to each other to form a ring together with the sulfur atom in the formula. As the cation represented by the general formula (ca-1), it is preferred that the cation be represented by any one of the above formulas (ca-1-55) to (ca-1-68), and more preferred that the cation be represented by any one of the above formulas (ca-1-63) to (ca-1-68).

[0680] • Regarding the (B2) component

[0681] The (B) component can also contain an acid generator component that does not belong to the above (B1) component (hereinafter referred to as "(B2) component"). The (B2) component is not particularly limited as long as it is a component that generates an acid by exposure and does not belong to the above (B1) component, and can be arbitrarily selected from publicly known components. As the (B2) component, there can be mentioned, for example, sulfonic acid oxime ester-based acid generators; diaalkyl or diaaryl sulfonyl diazomethane-based, poly(bis-sulfonyl) diazomethane-based, and the like, diazomethane-based acid generators; nitrobenzyl sulfonic acid salt-based acid generators, imino sulfonic acid salt-based acid generators, disulfone-based acid generators, and the like, various acid generators.

[0682] In the resist composition of the present embodiment, the (B) component can be used alone in one kind, or two or more kinds can be used in combination.

[0683] In the case where the resist composition contains the (B) component, the content of the (B) component in the resist composition is preferably less than 50 parts by mass, more preferably 1 to 40 parts by mass, and further preferably 5 to 25 parts by mass, relative to 100 parts by mass of the (A) component.

[0684] By setting the content of the (B) component within the above-mentioned preferable range, the pattern formation can be sufficiently performed. In addition, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is easily obtained, and the storage stability of the resist composition becomes good, and thus it is preferable.

[0685]

[0686] The resist composition of the present embodiment can further contain, in addition to the (A) component and the (Z) component, a base component (the (D) component) that traps the acid generated by exposure (i.e., controls the diffusion of the acid). The (D) component is a component that functions as a quencher (acid diffusion controller) that traps the acid generated in the resist composition by exposure.

[0687] As the (D) component, for example, a photodegradable base (D1) that loses the acid diffusion control property by exposure decomposition (hereinafter referred to as "(D1) component"), a nitrogen-containing organic compound (D2) that does not belong to the (D1) component (hereinafter referred to as "(D2) component"), and the like can be exemplified. Among them, from the viewpoint of maintaining the sensitivity in a thick resist film, the nitrogen-containing organic compound (D2) ((D2) component) is preferable. In the (D2) component, from the viewpoint of maintaining the transparency in a thick resist film, a chain alkyl amine is preferable.

[0688] • (D1) component

[0689] By providing the resist composition containing the (D1) component, the contrast between the exposed portion and the unexposed portion of the resist film can be further improved when the resist pattern is formed. As the (D1) component, there is no particular limitation as long as it is a component that loses the acid diffusion control property by exposure decomposition, and it is preferably one or more compounds selected from the group consisting of a compound represented by the following general formula (d1-1) (hereinafter referred to as "(d1-1) component"); a compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component"); and a compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1-3) component").

[0690] The (d1-1) to (d1-3) components lose the acid diffusion control property (basicity) by decomposition in the exposed portion of the resist film and thus cannot function as a quencher, but function as a quencher in the unexposed portion of the resist film.

[0691] [Chemical 63]​

[0692]

[0693] [In the formula, Rd 1 ~Rd 4 is a cyclic group which can have a substituent, a chain alkyl group which can have a substituent, or a chain alkenyl group which can have a substituent. Among them, Rd 2 in the formula (d1-2) is a carbon atom adjacent to the S atom, and is not bonded to a fluorine atom. Yd 1 is a single bond or a divalent linking group. m is an integer of 1 or more, and M m+ are each independently an organic cation of m valence.

[0694] {(d1-1) component}

[0695] anionic portion

[0696] In the formula (d1-1), Rd 1 is a cyclic group which can have a substituent, a chain alkyl group which can have a substituent, or a chain alkenyl group which can have a substituent, and the same groups as R 201 may be exemplified.

[0697] Among them, Rd 1 is preferably an aromatic hydrocarbon group which can have a substituent, an aliphatic cyclic group which can have a substituent, or a chain alkyl group which can have a substituent. As the substituent which these groups can have, a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluoroalkyl group, an intralactone-containing cyclic group represented by each of the above general formulae (a2-r-1) to (a2-r-7), an ether bond, an ester bond, or a combination thereof can be exemplified. In the case where an ether bond or an ester bond is included as the substituent, a linking group represented by each of the above formulae (y-al-1) to (y-al-5) is preferred as the substituent in this case.

[0698] As the aromatic hydrocarbon group, a polycyclic structure (a polycyclic structure composed of a bicyclooctane skeleton and a ring structure other than this) including a phenyl group, a naphthyl group, or a bicyclooctane skeleton can be preferably exemplified.

[0699] As the aliphatic cyclic group, a group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like is more preferred.

[0700] As the chain-like alkyl group, straight-chain alkyl groups having a carbon number of 1 to 10, specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, and the like; branched-chain alkyl groups having a carbon number of 1 to 10, specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, and the like.

[0701] In the case where the chain-like alkyl group is a fluoroalkyl group having a fluorine atom or a fluoroalkyl group as a substituent, the carbon number of the fluoroalkyl group is preferably 1 to 11, more preferably 1 to 8, and further preferably 1 to 4. The fluoroalkyl group can contain atoms other than fluorine atoms. As the atoms other than fluorine atoms, for example, oxygen atoms, sulfur atoms, nitrogen atoms, and the like can be exemplified.

[0702] As Rd 1 , a fluoroalkyl group in which hydrogen atoms constituting a straight-chain alkyl group are substituted with fluorine atoms is preferable, and a fluoroalkyl group in which all hydrogen atoms constituting a straight-chain alkyl group are substituted with fluorine atoms (straight-chain perfluoroalkyl group) is particularly preferable.

[0703] The following shows a preferable specific example of the anionic portion of the (d1-1) component.

[0704] [Chemical Formula 64]

[0705]

[0706] Anionic portion

[0707] In formula (d1-1), M m+ is an organic cation having valence m.

[0708] As the organic cation of M m+ , the same organic cations as those represented by the general formulas (ca-1) to (ca-4) can be preferably exemplified, and the cations represented by the general formula (ca-1) are more preferable, and the cations represented by the formulas (ca-1-1) to (ca-1-70) are further preferable.

[0709] The (d1-1) component can be used alone or in combination with two or more.

[0710] {(d1-2) component}

[0711] Anionic portion

[0712] In formula (d1-2), Rd 2 is a cyclic group which can have a substituent, a chain-like alkyl group which can have a substituent, or a chain-like alkenyl group which can have a substituent, and the same groups as those of R'201 Same group.

[0713] Among them, Rd 2 The carbon atom adjacent to the S atom in the (d1-2) component has no bonded fluorine atom (no fluorine substitution). As a result, the anion of the (d1-2) component becomes a moderately weak acid anion, which enhances its quenching ability as a (D) component.

[0714] As Rd 2 Preferably, it is a chain alkyl group that may have substituents or an aliphatic cyclic group that may have substituents. As a chain alkyl group, it is preferably 1 to 10 carbon atoms, more preferably 3 to 10. As an aliphatic cyclic group, it is more preferably a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (which may have substituents); or a group obtained by removing one or more hydrogen atoms from camphor, etc.

[0715] Rd 2 The hydrocarbon group may have substituents, and examples of such substituents include Rd of formula (d1-1). 1 The hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) can have the same substituents.

[0716] The following shows a preferred example of the anionic portion of component (d1-2).

[0717] [Chemistry 65]

[0718]

[0719] • Cation section

[0720] In equation (d1-2), M m+ An organic cation with a valence of m, and M in formula (d1-1) m+ same.

[0721] (d1-2) Components can be used alone or in combination of two or more.

[0722] {(d1-3)Component}

[0723] Anion section

[0724] In equation (d1-3), Rd 3 It can be a cyclic group that may have substituents, a chain-like alkyl group that may have substituents, or a chain-like alkenyl group that may have substituents; examples can be made with R'. 201 The same group is preferably a cyclic group containing a fluorine atom, a chain-like alkyl group, or a chain-like alkenyl group. Among them, fluoroalkyl groups are preferred, and more preferably those similar to the Rd group. 1 The same fluoroalkyl group as the fluoroalkyl group.

[0725] In formula (dl-3), Rd 4 is a cyclic group which can have a substituent, a chain alkyl group which can have a substituent, or a chain alkenyl group which can have a substituent, and the same groups as R 201 in the formula (dl-3) can be exemplified.

[0726] is preferably an alkyl group which can have a substituent, an alkoxy group which can have a substituent, an alkenyl group which can have a substituent, or a cyclic group.

[0727] Rd 4 in the formula (dl-3) is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, amyl, isoamyl, neopentyl, and the like can be exemplified. The alkyl group of Rd 4 in the formula (dl-3) can have a part of hydrogen atoms thereof substituted with a hydroxyl group, a cyano group, or the like.

[0728] Rd 4 in the formula (dl-3) is preferably an alkoxy group having 1 to 5 carbon atoms, and as the alkoxy group having 1 to 5 carbon atoms, specifically, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, t-butoxy can be exemplified. Among them, methoxy and ethoxy are preferred.

[0729] Rd 4 in the formula (dl-3) can exemplify the same groups as the alkenyl group of R 201 in the formula (dl-3), and is preferably vinyl, propenyl (allyl), 1-methylpropenyl, 2-methylpropenyl. These groups can 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.

[0730] Rd 4 in the formula (dl-3) can exemplify the same groups as the cyclic group of R 201 in the formula (dl-3), and is preferably an alicyclic group obtained by removing one or more hydrogen atoms from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or an aromatic group such as phenyl, naphthyl. In the case where Rd 4 is an alicyclic group, the resist composition is favorably dissolved in an organic solvent, and thus the lithography characteristics become favorable. Further, in the case where Rd 4 is an aromatic group, the light absorption efficiency of the resist composition is excellent in lithography using EUV or the like as an exposure light source, and the sensitivity and the lithography characteristics become favorable.

[0731] In formula (dl-3), Yd 1 is a single bond or a divalent linking group.

[0732] As Yd 1The divalent linking group in the formula (d1-3) is not particularly limited, and examples include divalent hydrocarbon groups (aliphatic hydrocarbon groups, aromatic hydrocarbon groups) that can have a substituent, heteroatom-containing divalent linking groups, and the like. Examples of these include the same groups as those exemplified in the description of the divalent linking group in the formula (a2-1) above. 21 The divalent linking group in the formula (d1-3) is not particularly limited, and examples include divalent hydrocarbon groups (aliphatic hydrocarbon groups, aromatic hydrocarbon groups) that can have a substituent, heteroatom-containing divalent linking groups, and the like. Examples of these include the same groups as those exemplified in the description of the divalent linking group in the formula (a2-1) above.

[0733] Yd 1 is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. As the alkylene group, more preferably a linear or branched alkylene group, and further preferably a methylene group or an ethylene group.

[0734] Preferred specific examples of the anion portion of the (d1-3) component are shown below.

[0735] [Chemical Formula 66]

[0736]

[0737] [Chemical Formula 67]

[0738]

[0739] ·· anion portion

[0740] In the formula (d1-3), M m+ is an m-valent organic cation, and is the same as M m+ in the formula (d1-1).

[0741] The (d1-3) component can be used alone or in combination with two or more kinds.

[0742] The (D1) component can be used alone or in combination with two or more kinds of the (d1-1) to (d1-3) components.

[0743] In the case where the resist composition contains the (D1) component, the content of the (D1) component in the resist composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, and further preferably 5 to 10 parts by mass, relative to 100 parts by mass of the (A) component.

[0744] If the content of the (D1) component is equal to or greater than the lower limit of the preferable range, particularly good lithography properties and resist pattern shapes are easily obtained. On the other hand, if it is equal to or less than the upper limit, the sensitivity is favorably maintained, and the throughput is also excellent.

[0745] Method for producing the (D1) component:

[0746] The production method of the (d1-1) component and the (d1-2) component is not particularly limited, and can be produced by a publicly known method.

[0747] Further, the production method of the (d1-3) component is not particularly limited, and can be produced, for example, in the same manner as the method described in US 2012-0149916.

[0748] • Regarding the (D2) component

[0749] As the (D) component, it is preferable to contain a nitrogen-containing organic compound component other than the (D1) component (hereinafter referred to as "(D2) component").

[0750] As the (D2) component, there is no particular limitation as long as it functions as an acid diffusion controller and is not the (D1) component, and any of publicly known components can be used. Among them, an aliphatic amine is preferable, and an aliphatic secondary amine or an aliphatic tertiary amine is particularly more preferable.

[0751] The aliphatic amine refers to an amine having one or more aliphatic groups, and the aliphatic group preferably has a carbon number of 1 to 12.

[0752] As the aliphatic amine, an amine (alkyl amine or alkyl alcohol amine) in which at least one hydrogen atom of ammonia NH3 is substituted with an alkyl group or a hydroxyalkyl group having a carbon number of 12 or less, or a cyclic amine can be exemplified.

[0753] As specific examples of the alkyl amine and the alkyl alcohol amine, a monoalkyl amine such as n-hexyl amine, n-heptyl amine, n-octyl amine, n-nonyl amine, n-decyl amine; a dialkyl amine such as diethyl amine, di-n-propyl amine, di-n-heptyl amine, di-n-octyl amine, dicyclohexyl amine; a trialkyl amine such as trimethyl amine, triethyl amine, tri-n-propyl amine, tri-n-butyl amine, tri-n-pentyl amine, tri-n-hexyl amine, tri-n-heptyl amine, tri-n-octyl amine, tri-n-nonyl amine, tri-n-decyl amine, tri-n-dodecyl amine; an alkyl alcohol amine such as diethanol amine, triethanol amine, diisopropanol amine, triisopropanol amine, di-n-octanol amine, tri-n-octanol amine can be exemplified. Among these, a trialkyl amine having a carbon number of 5 to 10 is further preferable, and tri-n-pentyl amine or tri-n-octyl amine is particularly preferable.

[0754] As the cyclic amine, for example, a heterocyclic compound containing a nitrogen atom as a hetero atom can be exemplified. As the heterocyclic compound, it can be a monocyclic compound (aliphatic monocyclic amine), or a polycyclic compound (aliphatic polycyclic amine).

[0755] As the aliphatic monocyclic amine, specifically, piperidine, piperazine, and the like can be exemplified. As the aliphatic polycyclic amine, it is preferable to have a carbon number of 6 to 10, and specifically, 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5.4.0]-7-undecene, hexamethylenetetramine, 1,4-diazabicyclo[2.2.2]octane, and the like can be exemplified.

[0756] As other aliphatic amines, there can be mentioned tri(2-methoxy- methoxyethyl)amine, tri{2-(2-methoxyethoxy)ethyl}amine, tri{2-(2- methoxyethoxymethoxy)ethyl}amine, tri{2-(l-methoxyethoxy)ethyl}amine, tri{2-(l-ethoxyethoxy)ethyl}amine, tri{2-(l-ethoxypropoxy)ethyl}amine, tri[2-{2-(2- hydroxyethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, and the like, with triethanolamine triacetate being preferred.

[0757] Further, as the (D2) component, an aromatic amine can be used.

[0758] As the aromatic amine, there can be mentioned 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, n-tert-butoxycarbonylpyrrolidine, and the like.

[0759] As the (D2) component, from the viewpoint of maintaining transparency in the thick film resist, an aliphatic amine is preferred, a chain aliphatic amine is more preferred, and a chain alkyl amine is further preferred. The chain alkyl group possessed by the chain alkyl amine preferably has a carbon number of 5 to 10. Among them, a dialkyl amine or a trialkyl amine having a straight chain alkyl group having a carbon number of 5 to 10 is preferred, and a trialkyl amine is more preferred.

[0760] The (D2) component can be used alone or in combination of two or more.

[0761] In the case where the resist composition contains the (D2) component, it is generally used in a range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the (A) component in the resist composition. By being set to the above range, the resist pattern shape, the standing time stability, and the like are improved.

[0762] "Compound (E) selected from at least one of the group consisting of organic carboxylic acids and phosphorus-containing oxo acids and derivatives thereof"

[0763] For the purpose of preventing sensitivity deterioration or improving the resist pattern shape, the standing time stability, and the like, a compound (E) (hereinafter referred to as "(E) component") selected from at least one of the group consisting of organic carboxylic acids and phosphorus-containing oxo acids and derivatives thereof can be contained in the resist composition of the present embodiment as an arbitrary component.

[0764] As the organic carboxylic acid, there are preferably, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid, and the like.

[0765] As the phosphorus-containing oxo acid, there can be mentioned phosphoric acid, phosphonic acid, phosphinic acid, and the like, among which phosphonic acid is particularly preferred.

[0766] As derivatives of phosphorus-containing oxo acids, for example, esters and the like obtained by substituting the hydrogen atom of the above-described phosphorus-containing oxo acids with a hydrocarbon group can be exemplified, and as the hydrocarbon group, an alkyl group having a carbon number of 1 to 5, an aryl group having a carbon number of 6 to 15, and the like can be exemplified.

[0767] As derivatives of phosphoric acid, phosphoric acid di-n-butyl ester, diphenyl phosphate, and the like phosphoric acid esters can be exemplified.

[0768] As derivatives of phosphonic acid, dimethyl phosphonate, di-n-butyl phosphonate, phenyl phosphonic acid, diphenyl phosphonate, dibenzyl phosphonate, and the like phosphonic acid esters can be exemplified.

[0769] As derivatives of phosphinic acid, phosphinic acid ester or phenyl phosphinic acid and the like can be exemplified.

[0770] In the resist composition of the present embodiment, the (E) component can be used alone in one kind, or two or more kinds can be used in combination.

[0771] In the case where the resist composition contains the (E) component, it is generally used in a range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the (A) component.

[0772] Fluorine additive component (F)

[0773] In order to impart water repellency to the resist film or in order to improve lithography characteristics, the resist composition of the present embodiment can contain a fluorine additive component (hereinafter referred to as "(F) component").

[0774] As the (F) component, for example, fluorine-containing high molecular compounds described in Japanese Patent Application Publication No. 2010-002870, Japanese Patent Application Publication No. 2010-032994, Japanese Patent Application Publication No. 2010-277043, Japanese Patent Application Publication No. 2011-13569, and Japanese Patent Application Publication No. 2011-128226 can be used.

[0775] As the (F) component, more specifically, a polymer having a structural unit (f1) represented by the following general formula (f1-1) can be exemplified. As the polymer, a polymer (homopolymer) composed 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); a copolymer of the structural unit (f1), a structural unit derived from acrylic acid or methacrylic acid, and the structural unit (a1) are preferred. Here, as the structural unit (a1) to be copolymerized with the structural unit (f1), a structural unit derived from 1-ethyl-1-cyclooctyl (meth) acrylate, a structural unit derived from 1-methyl-1-adamantyl (meth) acrylate are preferred.

[0776] [Chemical Formula 68]

[0777]

[0778] [In the formula, R is the same as described above, Rf 102 and Rf 103 each independently represents a hydrogen atom, a halogen atom, an alkyl group having a carbon number of 1 to 5, or a haloalkyl group having a carbon number of 1 to 5, Rf 102 and Rf 103 may be the same or different. nf 1 is an integer of 1 to 5, Rf 101 is an organic group containing a fluorine atom.

[0779] In formula (f1-1), R bonded to the carbon atom at the α-position is the same as described above. As R, a hydrogen atom or a methyl group is preferable.

[0780] In formula (f1-1), as Rf 102 and Rf 103 , a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like can be mentioned, and a fluorine atom is particularly preferable. As Rf 102 and Rf 103 , an alkyl group having a carbon number of 1 to 5, the same groups as the alkyl group having a carbon number of 1 to 5 of R described above can be mentioned, and a methyl group or an ethyl group is preferable. As Rf 102 and Rf 103 , a haloalkyl group having a carbon number of 1 to 5, specifically, a group in which a part or all of the hydrogen atoms of an alkyl group having a carbon number of 1 to 5 are substituted with halogen atoms can be mentioned. As the halogen atoms, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like can be mentioned, and a fluorine atom is particularly preferable. Among them, as Rf 102 and Rf 103 , a hydrogen atom, a fluorine atom, or an alkyl group having a carbon number of 1 to 5, preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group is preferable.

[0781] In formula (f1-1), nf 1 is an integer of 1 to 5, preferably an integer of 1 to 3, and more preferably 1 or 2.

[0782] In formula (f1-1), Rf 101 is an organic group containing a fluorine atom, and preferably a hydrocarbon group containing a fluorine atom.

[0783] As the hydrocarbon group containing a fluorine atom, any one of a straight chain, a branched chain, or a ring can be mentioned, and an alkyl group having a carbon number of 1 to 20 is preferable, an alkyl group having a carbon number of 1 to 15 is more preferable, and an alkyl group having a carbon number of 1 to 10 is particularly preferable.

[0784] Further, the hydrocarbon group containing a fluorine atom is preferably 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more are fluorinated, and particularly preferably 60% or more are fluorinated, from the viewpoint of improving the hydrophobicity of the resist film at the time of immersion exposure.

[0785] wherein Rf 101 More preferably, the fluorinated hydrocarbon group is one having a carbon number of 1 to 6, and particularly preferably, a trifluoromethyl group, -CH2-CF3, -CH2-CF2-CF3, -CH(CF3)2, -CH2-CH2-CF3, -CH2-CH2-CF2-CF2-CF2-CF3.

[0786] The weight average molecular weight (Mw) of the (F) component (polystyrene conversion basis based on gel permeation chromatography) is preferably 1000 to 50000, more preferably 5000 to 40000, and most preferably 10000 to 30000. If it is below the upper limit of this range, it has sufficient solubility in a solvent for use as a resist, and if it is above the lower limit of this range, the water repellency of the resist film is good.

[0787] The molecular weight distribution coefficient (Mw / Mn) of the (F) component is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

[0788] In the resist composition of the present embodiment, the (F) component can be used alone or two or more can be used in combination.

[0789] In the case where the resist composition contains the (F) component, it is generally used in a proportion of 0.5 to 10 parts by mass relative to 100 parts by mass of the (A) component.

[0790] "Organic Solvent Component (S)"

[0791] The resist composition of the present embodiment can be produced by dissolving a resist material in an organic solvent component (hereinafter referred to as "(S) component").

[0792] As the (S) component, any component can be appropriately selected from among substances conventionally known as solvents for chemically amplified resist compositions, provided that it can dissolve each of the components used to form a uniform solution.

[0793] For example, as the (S) component, mention can be made of lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl n- amyl ketone, methyl isopentyl ketone, 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate; monoalkyl ethers or monophenyl ethers of the polyhydric alcohols or the compounds having an ester bond such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, or mono- phenyl ether of the polyhydric alcohols or the compounds having an ester bond [among these, propylene glycol monomethyl ether acetate (PGMEA), 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, ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, methyl tolyl ether, diphenyl ether, dibenzyl ether, phenyl ethyl ether, butyl phenyl ether, ethyl benzene, diethyl benzene, amyl benzene, cumene, toluene, xylene, isopropyl toluene, mesitylene; dimethyl sulfoxide (DMSO) and the like.

[0794] In the resist composition of the present embodiment, the (S) component can be used singly as one kind, or can be used as a mixed solvent of two or more kinds. Among these, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

[0795] Further, as the (S) component, a mixed solvent obtained by mixing PGMEA with a polar solvent is also preferred. The blending ratio (mass ratio) of PGMEA to the polar solvent is appropriately determined taking into account the compatibility and the like of PGMEA with the polar solvent, and is preferably set to a range of 1 : 9 to 9 : 1, more preferably to a range of 2 : 8 to 8 : 2.

[0796] More specifically, in the case of blending EL or cyclohexanone as the polar solvent, the mass ratio of PGMEA to EL or cyclohexanone is preferably 1 : 9 to 9 : 1, more preferably 2 : 8 to 8 : 2. Further, in the case of blending PGME as the polar solvent, the mass ratio of PGMEA to PGME is preferably 1 : 9 to 9 : 1, more preferably 2 : 8 to 8 : 2, and further preferably 3 : 7 to 7 : 3. Furthermore, a mixed solvent of PGMEA and PGME and cyclohexanone is also preferred.

[0797] Further, as the (S) component, in addition to the above, a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferred. In this case, the mass ratio of the former to the latter is preferably set to 70 : 30 to 95 : 5.

[0798] The amount of use of the (S) component is set in such a manner that the solid content concentration of the resist composition is 25% by mass or more. In the present specification, the solid content in the resist composition refers to components other than the (S) component. The solid content concentration of the resist composition is calculated by the following formula.

[0799] Solid content concentration (% by mass) = (total mass of components other than the (S) component) / (total mass of the resist composition) x 100

[0800] For example, in the case where the resist composition is composed of the (A) component, the (Z) component, the (B) component, the (D) component, and the (S) component, the solid content concentration (% by mass) = [((A) component + (Z) component + (B) component + (D) component) / ((A) component + (Z) component + (B) component + (D) component) + (S) component] x 100.

[0801] By setting the solid content concentration of the resist composition to 25% by mass or more, in the case where the resist composition is applied to a substrate to form a resist film, a thick resist film (for example, a film thickness of 5 μm or more, preferably 7 μm or more) can be formed. The solid content concentration of the resist composition is not particularly limited as long as it is 25% by mass or more, and can be appropriately determined depending on the desired film thickness of the resist film. Generally, the higher the solid content concentration, the thicker the film thickness of the resist film.

[0802] The upper limit of the solid content concentration of the resist composition is not particularly limited as long as it is a concentration at which the solid content can be dissolved. The solid content concentration of the resist composition is, for example, 60% by mass or less, preferably 55% by mass or less, and more preferably 50% by mass or less.

[0803] As the range of the solid content concentration of the resist composition, for example, 25 to 60% by mass, 25 to 55% by mass, or 25 to 50% by mass, or the like can be exemplified.

[0804] In the resist composition of the present embodiment, an additive having miscibility, such as an additional resin for improving the properties of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an anti-halo agent, a dye, or the like can be further appropriately added as desired.

[0805] The resist composition of the present embodiment can also be used for removal of impurities and the like after dissolving the above-described resist material in the (S) component. For example, filtration of the resist composition can be performed using a filter composed of a polyimide porous membrane, a filter composed of a polyamide-imide porous membrane, a filter composed of a polyimide porous membrane and a polyamide-imide porous membrane, and the like. As the polyimide porous membrane and the polyamide-imide porous membrane, for example, those described in Japanese Patent Application Publication No. 2016-155121 and the like can be exemplified.

[0806] The solid component concentration of the resist composition of the present embodiment described above is 25% by mass or more, and contains a polyether compound having a weight average molecular weight of 400 or more at a prescribed ratio.

[0807] Since the solid component concentration of the resist composition of the present embodiment is 25% by mass or more, if applied to a substrate to form a resist film, a thick film resist film (for example, a film thickness of 5 μm or more) can be formed. With such a thick film resist film, cracks are easily generated on a resist pattern in conventional resist compositions. Furthermore, in conventional resist compositions, since light is difficult to reach the bottom, it is difficult to maintain the sensitivity at the time of exposure, and thus it is difficult to form a resist pattern of a good shape.

[0808] In the resist composition of the present embodiment, by containing a polyether compound having a weight average molecular weight of 400 or more at a prescribed ratio, both crack resistance and high resolution can be balanced. It is presumed that this is because, by having the polyether compound present in a resist film formed using the resist composition, the stress of the resist film is relaxed. Furthermore, by having the blending amount of the polyether compound within a prescribed range, a decrease in resolution can be suppressed.

[0809] (Resist pattern forming method)

[0810] The resist pattern forming method of the second aspect of the present application is a method having the following steps: a step of forming a resist film on a support using the resist composition of the above-described embodiment; a step of exposing the resist film; and a step of developing the exposed resist film to form a resist pattern.

[0811] As an embodiment of the above-described resist pattern forming method, for example, a resist pattern forming method performed as described below can be exemplified.

[0812] First, the resist composition of the above-described embodiment is applied to a support using a spin coater or the like, and baking (pre-baking (PAB)) treatment is performed at a temperature condition of, for example, 80 to 150°C for 40 to 120 seconds, preferably 60 to 90 seconds to form a resist film.

[0813] Next, for the resist film, for example, using an exposure device such as an electron beam drawing device, an EUV exposure device, and the like, after selective exposure by exposure through a mask (mask pattern) that forms a prescribed pattern, or drawing based on direct irradiation of electron rays without the mask pattern, and the like, a baking (post exposure bake (PEB)) treatment is performed for 40 to 120 seconds, preferably for 60 to 90 seconds, under temperature conditions of 80 to 150°C, for example.

[0814] Next, the resist film is subjected to a development treatment. In the case of an alkali development process, the development treatment is performed using an alkali developer, and in the case of a solvent development process, the development treatment is performed using a developer containing an organic solvent (organic developer).

[0815] After the development treatment, a rinsing treatment is preferably performed. In the case of an alkali development process, water rinsing using pure water is preferably performed, and in the case of a solvent development process, a rinsing liquid containing an organic solvent is preferably used.

[0816] In the case of a solvent development process, after the development treatment or the rinsing treatment, a treatment for removing the developer or the rinsing liquid adhering to the pattern by a supercritical fluid can be performed.

[0817] Drying is performed after the development treatment or the rinsing treatment. Furthermore, a baking treatment (post-baking) can be performed after the development treatment, as the case can be.

[0818] As described above, a resist pattern can be formed.

[0819] The support body is not particularly limited, and a conventionally known support body can be used, and a substrate for electronic parts, a support body on which a prescribed wiring pattern is formed, and the like can be exemplified. More specifically, a silicon wafer, a metal substrate such as a copper, a chromium, an iron, an aluminum, or the like, or a glass substrate, and the like can be exemplified. As a material for the wiring pattern, for example, copper, aluminum, nickel, gold, and the like can be used.

[0820] Furthermore, as the support body, a support body in which an inorganic and / or organic film is provided on the above-described substrate can be used. As the inorganic film, an inorganic anti-reflective film (inorganic BARC) can be exemplified. As the organic film, an organic anti-reflective film (organic BARC), a lower organic film in a multi-layer resist method, and the like can be exemplified.

[0821] Here, the multilayer resist method refers to 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 a resist pattern formed in the upper resist film is used as a mask to pattern the lower organic film, and is considered to be capable of forming a pattern with a high aspect ratio. That is, according to the multilayer resist method, the desired thickness can be ensured by the lower organic film, and thus the resist film can be thinned, and a fine pattern with a high aspect ratio can be formed.

[0822] In the multilayer resist method, basically, there are a method using a two-layer structure of an upper resist film and a lower organic film (2-layer resist method), and a method using a three-layer or more multilayer structure in which one or more intermediate layers (metal thin film, etc.) are provided between the upper resist film and the lower organic film (3-layer resist method).

[0823] In the resist pattern forming method of the present embodiment, since the resist composition of the above embodiment is used, a thick resist film can be formed in the process (i). The film thickness of the resist film is preferably 5 μm or more, more preferably 7 μm or more, and further preferably 8 μm or more. The upper limit of the film thickness of the resist film is, for example, 30 μm or less. As the range of the film thickness of the resist film formed in the process (i), for example, 5 to 30 μm can be exemplified, preferably 7 to 20 μm, more preferably 7 to 15 μm, and further preferably 8 to 12 μm. The film thickness of the resist film can be adjusted according to the solid content concentration of the resist composition used in the process (i). That is, the higher the solid content concentration of the resist composition, the higher film thickness of the resist film can be formed.

[0824] The wavelength used in the exposure is not particularly limited, and radiation such as ArF excimer laser, KrF excimer laser, F2 excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. can be used. The resist composition is highly useful for KrF excimer laser, ArF excimer laser, EB, or EUV, and is more highly useful for KrF excimer laser or ArF excimer laser, and is particularly highly useful for KrF excimer laser. That is, the resist pattern forming method of the present embodiment is particularly useful in a case where the process of exposing the resist film includes an operation of exposing the resist film to KrF excimer laser.

[0825] The exposure method of the resist film can be a general exposure (dry exposure) performed in air, inert gas such as nitrogen, etc., or can be liquid immersion exposure (Liquid Immersion Lithography).

[0826] Immersion exposure refers to an exposure method in which a solvent (immersion medium) having a refractive index larger than that of air is filled between an antirecording agent film and a lens at the lowermost position of an exposure apparatus, and exposure is performed in this state (immersion exposure).

[0827] As the immersion medium, a solvent having a refractive index larger than that of air and smaller than that of the exposed antirecording agent film is preferred. The refractive index of the solvent is not particularly limited as long as it is within the range.

[0828] As the solvent having a refractive index larger than that of air and smaller than that of the antirecording agent film, for example, water, fluorine-based inert liquid, silicon-based solvent, hydrocarbon-based solvent, etc. can be exemplified.

[0829] As a specific example of the fluorine-based inert liquid, a liquid in which a fluorine compound such as C3HCl2F5, C4F9OCH3, C4F9OC2H5, C5H3F7, etc. is a main component, etc. is exemplified, and a liquid having a boiling point of 70 to 180°C is preferred, and a liquid having a boiling point of 80 to 160°C is more preferred. If the fluorine-based inert liquid has a boiling point within the above range, removal of the medium for immersion after the exposure ends can be performed by a simple method and thus is preferred.

[0830] As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of an alkyl group are substituted with fluorine atoms is particularly preferred. As the perfluoroalkyl compound, specifically, a perfluoroalkyl ether compound or a perfluoroalkyl amine compound can be exemplified.

[0831] Further, specifically, as the perfluoroalkyl ether compound, perfluoro(2-butyl-tetrahydrofuran) (boiling point 102°C) can be exemplified, and as the perfluoroalkyl amine compound, perfluorotributyl amine (boiling point 174°C) can be exemplified.

[0832] As the immersion medium, from the viewpoints of cost, safety, environmental problems, versatility, etc., use of water is preferred.

[0833] As the alkaline developer solution used for development treatment in the alkaline development process, for example, a 0.1 to 10 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) can be exemplified.

[0834] As the organic solvent contained in the organic developer solution used for development treatment in the solvent development process, an organic solvent capable of dissolving the (A) component (the (A) component before exposure) can be appropriately selected from publicly known organic solvents. Specifically, polar solvents such as ketone-based solvents, ester-based solvents, alcohol-based solvents, nitrile-based solvents, amide-based solvents, ether-based solvents, etc., and hydrocarbon-based solvents, etc. can be exemplified.

[0835] A ketone solvent is an organic solvent including C-C(=0)-C in the structure. An ester solvent is an organic solvent including C-C(=0)-0-C in the structure. An alcohol solvent is an organic solvent including an alcoholic hydroxyl group in the structure. The "alcoholic hydroxyl group" means a hydroxyl group bonded to a carbon atom of an aliphatic hydrocarbon group. A nitrile solvent is an organic solvent including a nitrile group in the structure. An amide solvent is an organic solvent including an amide group in the structure. An ether solvent is an organic solvent including C-O-C in the structure.

[0836] Among the organic solvents, there are also organic solvents including a plurality of functional groups having the characteristics of each of the above-described solvents in the structure, in which case the organic solvent is classified into all the solvent categories having the functional groups possessed. For example, diethylene glycol monomethyl ether is classified into either of the above-described alcohol solvent or ether solvent.

[0837] A hydrocarbon solvent is a hydrocarbon solvent composed of a halogenatable hydrocarbon, having no substituent other than a halogen atom. As the halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like can be exemplified, and a fluorine atom is preferred.

[0838] As the organic solvent contained in the organic developer, among the above, a polar solvent is preferred, and a ketone solvent, an ester solvent, a nitrile solvent, and the like are preferred.

[0839] As the ketone solvent, for example, 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylpropyl ketone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, diaceton, ionone, diaceton alcohol, acetyl carbinol, phenylethyl ketone, methylnaphthyl ketone, isophorone, propylene carbonate, γ-butyrolactone, methyl amyl ketone (2-heptanone), and the like can be exemplified. Among these, as the ketone solvent, methyl amyl ketone (2-heptanone) is preferred.

[0840] As the ester-based solvent, for example, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, 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, 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, propyl lactate, 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, and the like can be exemplified. Among these, as the ester-based solvent, butyl acetate is preferred.

[0841] As the nitrile-based solvent, for example, acetonitrile, propionitrile, valeronitrile, butyronitrile, and the like can be exemplified.

[0842] In the organic developer, a known additive can be blended as necessary. As the additive, for example, a surfactant can be exemplified. As the surfactant, there is no particular limitation, and for example, an ionic, non-ionic, fluorine-based and / or silicon-based surfactant, and the like can be used. As the surfactant, a non-ionic surfactant is preferred, and a non-ionic fluorine-based surfactant or a non-ionic silicon-based surfactant is more preferred.

[0843] In the case where the surfactant is blended, the blending amount thereof is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass, relative to the total amount of the organic developer.

[0844] The developing treatment can be performed by a publicly known developing method, for example, a method in which the support is immersed in a developing solution for a certain period of time (immersion method), a method in which a developing solution is carried on the surface of the support by surface tension and left still for a certain period of time (puddle method), a method in which a developing solution is sprayed to the surface of the support (spray method), a method in which a developing solution is continuously applied to a support rotating at a certain speed while a nozzle from which the developing solution is applied is scanned at a certain speed (dynamic dispensing method), and the like.

[0845] As the organic solvent contained in the rinsing solution used for the rinsing treatment after the developing treatment in the solvent developing process, for example, an organic solvent which is difficult to dissolve the resist pattern among the organic solvents exemplified as the organic solvent for the organic developing solution can be appropriately selected. At least one solvent selected from a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, an amide-based solvent, and an ether-based solvent is generally used. Among these, at least one selected from a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, and an amide-based solvent is preferred, at least one selected from an alcohol-based solvent and an ester-based solvent is more preferred, and an alcohol-based solvent is particularly preferred.

[0846] The alcohol-based solvent used in the rinsing solution is preferably a monohydric alcohol having a carbon number of 6 to 8, and the monohydric alcohol can be any one of a straight chain, a branched chain, or a cyclic. Specifically, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, benzyl alcohol, and the like can be exemplified. Among these, 1-hexanol, 2-heptanol, 2-hexanol are preferred, and 1-hexanol, 2-hexanol are more preferred.

[0847] These organic solvents can be used alone as any one of them or in combination of two or more. In addition, they can be used in combination with an organic solvent other than the above or water. Among these, if the developing properties are taken into consideration, the amount of water to be mixed in the rinsing solution is preferably 30% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, and particularly preferably 3% by mass or less, relative to the total amount of the rinsing solution.

[0848] In the rinsing solution, a publicly known additive can be mixed as needed. As the additive, for example, a surfactant can be exemplified. The surfactant can be exemplified as the same surfactants as described above, and a nonionic surfactant is preferred, and a nonionic fluorine-based surfactant or a nonionic silicon-based surfactant is more preferred.

[0849] In the case where a surfactant is mixed, the amount of the surfactant to be mixed is generally 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass, relative to the total amount of the rinsing solution.

[0850] The rinsing treatment (cleaning treatment) using the rinsing liquid can be performed by a publicly known rinsing method. As the method of the rinsing treatment, for example, a method in which the rinsing liquid is continuously applied to a support body rotating at a certain speed (spin coating method), a method in which the support body is immersed in the rinsing liquid for a certain time (immersion method), a method in which the support body surface is sprayed with the rinsing liquid (spray coating method), and the like can be exemplified.

[0851] According to the resist pattern forming method of the present embodiment described above, since the resist composition of the above-described first aspect is used, a resist pattern having less cracks and high resolution can be formed.

[0852] The above-described resist pattern forming method is useful as a method for manufacturing a three-dimensional structure device.

[0853] Examples

[0854] Hereinafter, the present application will be further explained by examples, but the present application is not limited by these examples.

[0855] Preparation of resist composition

[0856] (Examples 1 to 18, Comparative Examples 1 to 7)

[0857] Each of the resist compositions of the examples was prepared by mixing and dissolving each of the components shown in Tables 1 to 3.

[0858] [Table 1]

[0859]

[0860] [Table 2]

[0861]

[0862] [Table 3]

[0863]

[0864] In Tables 1 to 3, each of the abbreviations has the following meaning. The values in the brackets are the blending amounts (mass parts). The solid content concentration was calculated by the following formula: solid content concentration (mass %) = [((A) component + (B) component + (D) component + (Z) component) / ((A) component + (B) component + (D) component + (Z) component + (S) component)] x 100.

[0865] (A)-1: A high molecular compound represented by the following Chemical Formula (A-1). The weight average molecular weight (Mw) converted into a polystyrene standard, which was measured by GPC, was 10,000, and the molecular weight distribution coefficient (Mw / Mn) was 1.4. The acid value was 0.1 mgKOH / g, and the hydroxyl value was 0.1 mgKOH / g. 13The copolymer composition ratio (the ratio of each structural unit (molar ratio) in the structural formula) determined by C-NMR was 1 / m / n = 60 / 15 / 25.

[0866] [Chemical Formula 69]

[0867]

[0868] (B)-1: An acid generator composed of a compound represented by the following Chemical Formula (B-1).

[0869] (B)-2: An acid generator composed of a compound represented by the following Chemical Formula (B-2).

[0870] (B)-3: An acid generator composed of a compound represented by the following Chemical Formula (B-3).

[0871] (B)-4: An acid generator composed of a compound represented by the following Chemical Formula (B-4).

[0872] (B)-5: An acid generator composed of a compound represented by the following Chemical Formula (B-5).

[0873] (B)-6: An acid generator composed of a compound represented by the following Chemical Formula (B-6).

[0874] [Chemical Formula 70]

[0875]

[0876] (D)-1: A photodegradable base composed of a compound represented by the following Chemical Formula (D-1).

[0877] [Chemical Formula 71]

[0878]

[0879] (Z1)-1: Polypropylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, determined by GPC measurement, was 400.

[0880] (Z1)-2: Polypropylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, determined by GPC measurement, was 1000.

[0881] (Z1)-3: Polypropylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, determined by GPC measurement, was 3000.

[0882] (Z1)-4: Polypropylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, determined by GPC measurement, was 4000.

[0883] (Z1)-5: Polyethylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, which was measured by GPC, was 1000.

[0884] (Z1)-6: Polyethylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, which was measured by GPC, was 4000.

[0885] (Z1)-7: Polyethylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, which was measured by GPC, was 8000.

[0886] (Z1)-8: Polyethylene glycol. The weight average molecular weight (Mw) converted into a polystyrene standard, which was measured by GPC, was 20000.

[0887] (Z2)-1 : A compound represented by the following formula (Z2-1). Molecular weight 193.

[0888] (Z2)-2: A compound represented by the following formula (Z2-2). Molecular weight 164.

[0889] (Z2)-3: A compound represented by the following formula (Z2-3). Molecular weight 238.

[0890] (Z2)-4: A compound represented by the following formula (Z2-4). Molecular weight 282.

[0891] [Chemical 72]

[0892]

[0893] (S)-1 : A mixed solvent of propylene glycol monomethyl ether / propylene glycol monomethyl ether acetate = 4 / 1 (mass ratio).

[0894] [Formation of resist pattern]

[0895] Step (i):

[0896] On an 8-inch silicon wafer on which hexamethyldisilazane (HMDS) treatment at 110°C for 60 seconds was carried out, each of the resist compositions of Examples was applied using a spin coater. Drying was carried out by prebaking (PAB) treatment at 160°C for 120 seconds on a hot plate, thereby forming a resist film having a film thickness of 12 μm.

[0897] Step (ii):

[0898] Next, the resist film was selectively irradiated with KrF excimer laser light (248 nm) via a mask pattern (binary mask) using a KrF exposure device NSR-S203B (manufactured by Nikon Corporation; NA (numerical aperture) = 0.60, σ = 0.68).

[0899] Then, it undergoes a post-exposure heating (PEB) treatment at 110°C for 90 seconds.

[0900] Process (iii):

[0901] Next, alkaline development was performed using a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution “NMD-3” (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) as the developer at 23°C for 60 seconds.

[0902] Then, bake at 100°C for 60 seconds.

[0903] The result is the formation of isolated spaced patterns with a spacing width of 1 to 3 μm.

[0904] [Crack Resistance Evaluation]

[0905] A silicon wafer with an isolated spacer pattern formed through the above-described "Resist Pattern Formation" was placed in the chamber of a scanning electron microscope S-9380 (manufactured by Hitachi High Technology Co., Ltd.) and subjected to vacuum treatment for 60 seconds at a pressure of 0.0001 Pa. The silicon wafer after vacuum treatment was observed using an optical microscope, and the number of cracks was counted. The number of cracks was evaluated based on the following evaluation criteria. The results are shown as "cracks" in Tables 4 and 5.

[0906] Evaluation Criteria

[0907] ◎: There are 0 cracks.

[0908] ○: 1 to 5 cracks

[0909] ×: There are 6 or more cracks

[0910] [Resolution Evaluation]

[0911] Determine the optimal exposure value Eop (μC / cm) for forming a 3μm isolated spacing pattern in the above <Resist Pattern Formation>. 2 Furthermore, using the optimal exposure value Eop as the exposure value, a 1 μm isolated spacer pattern was formed through the above-described <Resist Pattern Formation>. The pattern shape of the 1 μm isolated spacer pattern was observed using a scanning electron microscope S-9380 (manufactured by Hitachi High Technology Co., Ltd.), and evaluated based on the following evaluation criteria. These are shown as "resolution" in Tables 4 and 5.

[0912] Evaluation Criteria

[0913] ◎: The pattern is reliably formed onto the substrate.

[0914] ○: A slight curled edge shape was observed.

[0915] X: pattern was not peeled off.

[0916] Table 4

[0917] cracks resolution example 1 ◎ ◎ example 2 ◎ ◎ example 3 ◎ ◎ example 4 ○ ◎ example 5 ◎ ◎ example 6 ◎ ○ example 7 ◎ ◎ example 8 ◎ ◎ example 9 ◎ ◎ example 10 ◎ ◎ example 11 ◎ ◎ example 12 ○ ◎ example 13 ◎ ◎ example 14 ◎ ◎ example 15 ◎ ◎ example 16 ◎ ◎ example 17 ◎ ◎ example 18 ◎ ◎

[0918] Table 5

[0919] cracks resolution comparative example 1 × ◎ comparative example 2 × ◎ comparative example 3 ◎ × comparative example 4 × ◎ comparative example 5 × ◎ comparative example 6 × ◎ comparative example 7 × ◎

[0920] According to the results shown in Table 4 and Table 5, the crack resistance and the resolution of the resist compositions of Examples 1 to 17 are both good. On the other hand, either the crack resistance or the resolution of the resist compositions of Comparative Examples 1 to 7 is poor.

Claims

1. A photoresist composition that generates acid upon exposure and whose solubility in a developer changes with the action of the acid, characterized in that, contain: Substrate composition whose solubility in developer changes due to the action of acid (A); Polyethylene glycol with a weight-average molecular weight of 1000 or higher; and Acid-producing component (B) that generates acid through exposure. The content of polyethylene glycol is 0.8 to 32 parts by weight relative to 100 parts by weight of the substrate component (A). The acid-producing agent component (B) has a cationic portion represented by the following chemical formula (ca-1-16) or the following general formula (ca-1-66). wherein R 201 is a hydrogen atom or a substituent, and the substituent is an alkyl group, a halogen atom, a halogenated alkyl group, a cyano group, an amino group, an aryl group, or a group represented by any one of general formulae (ca-r-1) to (ca-r-7), R 201 are each independently a hydrogen atom, a cyclic group which can have a substituent, a chain alkyl group which can have a substituent, or a chain alkenyl group which can have a substituent, The solid component concentration of the resist composition is 25% by mass or more.

2. A resist pattern forming method characterized by, The device comprises: a step of forming a resist film on a support using the resist composition of claim 1; a step of exposing the resist film; and a step of developing the exposed resist film to form a resist pattern.

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