Actinic-ray-sensitive or radiation-sensitive resin composition, resist film, pattern forming method, electronic device production method, and onium salt compound

Abstract

Provided are: an actinic-ray-sensitive or radiation-sensitive resin composition, comprising an onium salt compound (N) represented by general formula (N-1) described in the description, a resin the polarity of which changes by an action of an acid, and a solvent; a resist film, pattern forming method, and electronic device production method, which use the actinic-ray-sensitive or radiation-sensitive resin composition; and an onium salt compound represented by general formula (N-1) described in the description.

Description

Photosensitive or radiation-sensitive resin compositions, resist films, pattern forming methods, methods for manufacturing electronic devices, and onium salt compounds

[0001] The present invention relates to a photosensitive or radiation-sensitive resin composition, a resist film, a pattern formation method, a method for manufacturing an electronic device, and an onium salt compound. More specifically, the present invention relates to a photosensitive or radiation-sensitive resin composition, a resist film, a pattern formation method, a method for manufacturing an electronic device, and an onium salt compound that can be suitably used in the above photosensitive or radiation-sensitive resin composition, which can be suitably used in ultramicrolithography processes applicable to the manufacturing processes of ultra-LSI (Large Scale Integration) and high-capacity microchips, nanoimprint mold creation processes and high-density information recording media, and other photofabrication processes.

[0002] Traditionally, in the manufacturing processes of semiconductor devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations), microfabrication has been performed using lithography with resist compositions. In recent years, with the increasing integration of integrated circuits, there has been a growing demand for the formation of ultrafine patterns in the submicron or quarter-micron region. Accordingly, there has been a trend toward shorter exposure wavelengths, from the g-line to the i-line, and further to KrF excimer laser light. Currently, exposure machines using ArF excimer lasers with a wavelength of 193 nm as the light source have been developed. Furthermore, as a technique to further improve resolution, development of the so-called immersion method has been progressing, in which a high refractive index liquid (hereinafter also called "immersion liquid") is filled between the projection lens and the sample.

[0003] Furthermore, in addition to excimer laser light, lithography using electron beams (EB), X-rays, and extreme ultraviolet (EUV) light is currently under development. Accordingly, resist compositions that are effectively sensitive to various types of active light or radiation are being developed.

[0004] For example, Patent Document 1 discloses a radiation-sensitive resin composition containing a compound having a hydroxybenzoate anion with a specific substituent on an aromatic ring.

[0005] International Publication No. 2023 / 199907

[0006] The present inventors prepared and investigated a photosensitive or radiation-sensitive resin composition containing a compound having the above-mentioned predetermined anion, with reference to Patent Document 1, and found that there was a difference in sensitivity between a pattern formed after the composition has been stored over time and a pattern formed immediately after the composition has been manufactured.

[0007] Therefore, the object of the present invention is to provide a photosensitive or radiation-sensitive resin composition capable of forming patterns with minimal sensitivity fluctuations due to storage of the composition over time. Furthermore, the object of the present invention is to provide a resist film, a pattern formation method, a method for manufacturing an electronic device, and an onium salt compound suitably used with the above photosensitive or radiation-sensitive resin composition.

[0008] The inventors have found that the above problems can be solved by the following configuration.

[0009] [1] A photosensitive or radiation-sensitive resin composition comprising an onium salt compound (N) represented by the following general formula (N-1), a resin whose polarity changes upon the action of an acid, and a solvent.

[0010]

[0011] In the general formula (N-1), Ar represents an aromatic ring group. １ and R ２ Each of these independently represents a hydrogen atom, a halogen atom, or a monovalent organic group. X is -CO ２ － , -SO ２ NR １ R ２represents a monovalent substituent other than those defined above. m represents an integer of 0 or more. When m is an integer of 2 or more, the plurality of Xs may be the same or different, and the plurality of Xs may be linked to form a ring. n represents an integer of 1 or more. When n is an integer of 2 or more, the plurality of R １ and R ２ may each be the same or different. r represents an integer of 1 or more. Ma ｐ＋ represents a p-valent onium cation. p and q each independently represent an integer of 1 or more, provided that p×q = r is satisfied.

[0012] [2] The radiation-sensitive or radiation-sensitive resin composition according to [1], wherein at least one of R １ and R ２ in the general formula (N-1) is a hydrogen atom. [3] In the general formula (N-1), -CO ２ － is bonded to an annular atom adjacent to the annular atom in Ar to which -SO ２ NR １ R ２ at least one of which is bonded. The radiation-sensitive or radiation-sensitive resin composition according to [1] or [2]. [4] The radiation-sensitive or radiation-sensitive resin composition according to any one of [1] to [3], wherein at least one of Xs in the general formula (N-1) contains a halogen atom.

[0013] [5] The radiation-sensitive or radiation-sensitive resin composition according to any one of [1] to [4], wherein Ma ｐ＋ in the general formula (N-1) contains a fluorine atom or an iodine atom. [6] The radiation-sensitive or radiation-sensitive resin composition according to any one of [1] to [5], wherein the resin contains a repeating unit having an aromatic ring. [7] The radiation-sensitive or radiation-sensitive resin composition according to any one of [1] to [6], wherein the resin contains a repeating unit having a hydroxyl group bonded to an aromatic ring.

[0014] [8] A resist film formed using the photosensitive or radiation-sensitive resin composition described in any one of [1] to [7]. [9] A pattern forming method comprising the steps of: forming a resist film on a substrate using the photosensitive or radiation-sensitive resin composition described in any one of [1] to [7]; exposing the resist film; and developing the exposed resist film using a developer to form a pattern.

[10] A method for manufacturing an electronic device, comprising the pattern forming method described in [9].

[0015]

[11] Onium salt compounds represented by the following general formula (N-1).

[0016]

[0017] In the general formula (N-1), Ar represents an aromatic ring group. １ and R ２ Each of these independently represents a hydrogen atom, a halogen atom, or a monovalent organic group. X is -CO ２ － , -SO ２ NR １ R ２ Represents a monovalent substituent other than . m represents an integer of 0 or more. If m is an integer of 2 or more, multiple Xs may be the same or different, and multiple Xs may be linked to form a ring. n represents an integer of 1 or more. If n is an integer of 2 or more, multiple R １ and R ２ These can be the same or different. r represents an integer greater than or equal to 1. Ma ｐ＋ represents a p-valent onium cation. p and q are independent integers greater than or equal to 1, where p × q = r.

[0018]

[12] R in the above general formula (N-1) １ and R ２ The onium salt compound according to

[11] , wherein at least one of the is a hydrogen atom.

[13] In the above general formula (N-1), -CO ２ － -SO ２ NR １ R２ An onium salt compound according to

[11] or

[12] , wherein at least one of is bonded.

[14] An onium salt compound according to any one of

[11] to

[13] , wherein at least one of X in the above general formula (N-1) contains a halogen atom.

[15] Ma in the above general formula (N-1) ｐ＋ An onium salt compound according to any one of

[11] to

[14] , comprising a fluorine atom or an iodine atom.

[0019] According to the present invention, it is possible to provide a photosensitive or radiation-sensitive resin composition capable of forming a pattern with little sensitivity variation due to storage of the composition over time, a resist film formed from the photosensitive or radiation-sensitive resin composition, a pattern formation method and a method for manufacturing an electronic device using the photosensitive or radiation-sensitive resin composition, and an onium salt compound that can be suitably used in the photosensitive or radiation-sensitive resin composition.

[0020] The present invention will now be described in detail. The following descriptions of the constituent elements may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0021] In this specification, "active light" or "radiation" means, for example, the emission spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light (EUV), X-rays, soft X-rays, and electron beams (EB). In this specification, "light" means active light or radiation. In this specification, unless otherwise specified, "exposure" includes not only exposure with emission spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light, and X-rays, but also drawing with particle beams such as electron beams and ion beams.

[0022] In this specification, "~" means that the numbers before and after it are included as the lower and upper limits. In this specification, (meth)acrylate represents at least one of acrylate and methacrylate. Also, (meth)acrylic acid represents at least one of acrylic acid and methacrylic acid.

[0023] In this specification, the weight-average molecular weight (Mw), number-average molecular weight (Mn), and degree of dispersion (also called molecular weight distribution) (Mw / Mn) of a resin are defined as polystyrene equivalent values ​​obtained by GPC (Gel Permeation Chromatography) measurement using a GPC (Gel Permeation Chromatography) instrument (HLC-8120GPC manufactured by Tosoh Corporation) (solvent: tetrahydrofuran, flow rate (sample injection volume): 10 μL, column: TSK gel Multipore HXL-M manufactured by Tosoh Corporation, column temperature: 40°C, flow rate: 1.0 mL / min, detector: differential refractive index detector).

[0024] In this specification, regarding the notation of groups (atomic groups), unless contrary to the spirit of the present invention, notations that do not specify substituted or unsubstituted include both groups with and without substituents. For example, "alkyl group" includes not only alkyl groups without substituents (unsubstituted alkyl groups) but also alkyl groups with substituents (substituted alkyl groups). Furthermore, in this specification, "organic group" means a group containing at least one carbon atom. Unless otherwise specified, monovalent substituents are preferred. Examples of substituents include monovalent nonmetallic atomic groups excluding hydrogen atoms, and can be selected from, for example, the following substituent T.

[0025] (Substituent T) Substituents T include halogen atoms such as fluorine, chlorine, bromine, and iodine; alkoxy groups such as methoxy, ethoxy, and tert-butoxy; cycloalkyloxy groups; aryloxy groups such as phenoxy and p-tolyloxy; alkoxycarbonyl groups such as methoxycarbonyl and butoxycarbonyl; cycloalkyloxycarbonyl groups; aryloxycarbonyl groups such as phenoxycarbonyl; acyloxy groups such as acetoxy, propionyloxy, and benzoyloxy; acetyl, benzoyl, isobutyryl, acryloyl, and meta Examples of substituents include acyl groups such as kryloyl and methoxalyl groups; sulfanyl groups; alkylsulfanyl groups such as methylsulfanyl and tert-butylsulfanyl groups; arylsulfanyl groups such as phenylsulfanyl and p-tolylsulfanyl groups; alkylsulfonyl groups; arylsulfonyl groups; alkyl groups; alkenyl groups; cycloalkyl groups; aryl groups; heteroaryl groups; hydroxyl groups; carboxyl groups; formyl groups; sulfo groups; cyano groups; alkylaminocarbonyl groups; arylaminocarbonyl groups; sulfonamide groups; silyl groups; amino groups; carbamoyl groups; and so on. Furthermore, if these substituents can have one or more substituents, groups having one or more substituents selected from the substituents listed above as further substituents (for example, monoalkylamino groups, dialkylamino groups, arylamino groups, trifluoromethyl groups, etc.) are also included as examples of substituent T.

[0026] In this specification, the bonding direction of the divalent group as expressed is not limited unless otherwise specified. For example, in a compound represented by the formula "X-Y-Z", if Y is -COO-, Y may also be -CO-O- or -O-CO-. The above compound may also be "X-CO-O-Z" or "X-O-CO-Z".

[0027] In this specification, the acid dissociation constant (pKa) refers to the pKa in aqueous solution, and specifically, it is a value calculated using the software package 1 described below, based on a database of Hammett substituent constants and known literature values. All pKa values ​​described in this specification are values ​​calculated using this software package. Software package 1: Advanced Chemistry Development (ACD / Labs) Software V8.14 for Solaris (1994-2007 ACD / Labs).

[0028] Furthermore, pKa can also be determined by molecular orbital calculations. Specifically, this method involves calculating the H₂ in aqueous solution based on the thermodynamic cycle. ＋ One method is to calculate the dissociation free energy. ＋ The dissociation free energy can be calculated using, for example, the Density Functional Theory (DFT), but various other methods have been reported in the literature and are not limited to this. Several software programs exist that can perform DFT, such as Gaussian 16.

[0029] In this specification, pKa refers to a value calculated using software package 1 based on a database of Hammett substituent constants and known literature values, as described above. However, if pKa cannot be calculated using this method, the value obtained by Gaussian 16 based on DFT (density functional theory) shall be adopted. In this specification, pKa refers to "pKa in aqueous solution" as described above. However, if pKa in aqueous solution cannot be calculated, "pKa in dimethyl sulfoxide (DMSO) solution" shall be adopted.

[0030] In this specification, "solids" refers to components contained in a photosensitive or radiation-sensitive resin composition (hereinafter also referred to as a "resist composition") that form a resist film, and does not include solvents. Furthermore, any component contained in a resist composition that forms a resist film is considered a solid, even if its state is liquid.

[0031] [Photosensitive or Radiation-Sensitive Resin Composition] The photosensitive or radiation-sensitive resin composition of the present invention (hereinafter also simply referred to as "resist composition" or "the resist composition of the present invention") will be described in detail below. The resist composition of the present invention comprises an onium salt compound (N) represented by the general formula (N-1) described later, a resin whose polarity changes upon the action of an acid, and a solvent. The resist composition may be a positive-type resist composition or a negative-type resist composition, but it is preferably a negative-type resist composition. Furthermore, the resist composition may be a resist composition for alkaline development or a resist composition for organic solvent development, but it is preferably a resist composition for organic solvent development. The resist composition may be a chemically amplified resist composition or a non-chemically amplified resist composition, but it is preferably a chemically amplified resist composition.

[0032] The reason why a resist composition having the above configuration can solve the problems of the present invention is not entirely clear, but the inventors speculate as follows. It should be noted that the following speculation does not limit the mechanism by which the effect is obtained. In other words, even if the effect is obtained by a mechanism other than those described below, it is still within the scope of the present invention.

[0033] The resist composition of the present invention comprises an onium salt compound (N). The onium salt compound (N) is -CO ２ － A sulfonamide group is further bonded to the aromatic ring group to which the compound is attached. This sulfonamide group causes -CO ２ －Because the nucleophilicity of the resist is reduced, the storage stability of the resist composition is improved, and it is presumed that sensitivity changes due to storage over time are less likely to occur. Hereinafter, the ability to form a pattern with less sensitivity change due to storage over time of the resist composition will also be referred to as "the effect of the present invention is superior."

[0034] [Onium Salt Compound (N)] The resist composition of the present invention contains an onium salt compound (N) represented by the following general formula (N-1). The onium salt compound (N) functions as an acid diffusion control agent. The acid diffusion control agent can act as a quencher that traps excess acid generated from, for example, the photoacid generator described later by irradiation with active light or radiation (hereinafter also simply referred to as "exposure"), and suppresses the reaction of the acid-degradable resin in the unexposed areas due to the excess acid. Note that the onium salt compound (N) contains (for example, X, R in general formula (N-1)) １ , and R ２ If the compound (N) further contains a strong acid anion such as a sulfonate anion or a sulfonimide anion (in either case), the onium salt compound (N) can also function as a photoacid generator. A photoacid generator is a compound that generates acid upon exposure to light.

[0035]

[0036] In the general formula (N-1), Ar represents an aromatic ring group. １ and R ２ Each of these independently represents a hydrogen atom, a halogen atom, or a monovalent organic group. X is -CO ２ － , -SO ２ NR １ R ２ Represents a monovalent substituent other than . m represents an integer of 0 or more. If m is an integer of 2 or more, multiple Xs may be the same or different, and multiple Xs may be linked to form a ring. n represents an integer of 1 or more. If n is an integer of 2 or more, multiple R １ and R ２ These can be the same or different. r represents an integer greater than or equal to 1. Ma ｐ＋represents a p-valent onium cation. p and q are independent integers greater than or equal to 1, where p × q = r.

[0037] In the general formula (N-1), Ar represents an aromatic ring group. The aromatic ring in the aromatic ring group represented by Ar may be an aromatic hydrocarbon ring or an aromatic heterocycle.

[0038] The aromatic hydrocarbon ring may be monocyclic or polycyclic. The number of ring member atoms is preferably 6 to 15, and more preferably 6 to 10. Examples of aromatic hydrocarbon rings include benzene rings, naphthalene rings, and anthracene rings. Among these, benzene rings or naphthalene rings are preferred, and benzene rings are more preferred.

[0039] Aromatic heterocycles may be monocyclic or polycyclic. The number of ring member atoms is preferably 5 to 15. An aromatic heterocycle represents a heterocycle that possesses aromaticity. Examples of aromatic heterocycles include furan rings, thiophene rings, benzofuran rings, benzothiophene rings, dibenzofuran rings, dibenzothiophene rings, pyridine rings, indole rings, benzodiazole rings, carbazole rings, and the like.

[0040] The aromatic ring in the aromatic ring group represented by Ar is preferably an aromatic hydrocarbon ring, and more preferably a benzene ring.

[0041] In general formula (N-1), R １ and R ２ Each of these independently represents a hydrogen atom, a halogen atom, or a monovalent organic group.

[0042] R １ and R ２ Examples of halogen atoms represented by include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms or iodine atoms being preferred.

[0043] R １ and R ２ The monovalent organic group represented by is not particularly limited, and examples include the group shown in organic group W below.

[0044] (Organic group W) The organic group W is, for example, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a cycloalkynyl group, an aryl group, a heteroaryl group, an aralkyl group, a cyano group, an alkoxy group, an aryloxy group, a heterocyclic oxy group, an acyl group (alkylcarbonyl group or arylcarbonyl group), an acyloxy group (alkylcarbonyloxy group or arylcarbonyloxy group), a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, an alkyl or arylsulfinyl group, an alkyl or arylsulfonyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a cycloalkoxycarbonyl group, an aryl or heterocyclic azo group, a sulfonamide group, an imide group, an acylamino group, a carbamoyl group, and a lactone group, etc.

[0045] Each of the above groups may further have a substituent if possible. For example, an alkyl group that may have a substituent is also included as one form of the organic group W. The above substituents are not particularly limited, and for example, the above-described substituent T can be mentioned.

[0046] Each of the above groups may have an ionic group as a substituent. For example, -SO ３ － Mb ＋ (Mb ＋ represents an onium cation) may be included. Also, each of the above groups may have a sulfonimide anion (-SO ２ -N － (Mb ＋ )-SO ２ -) as an ionic group between two adjacent carbon atoms in each group. The onium cation represented by Mb ＋ is preferably a cation represented by the formula (ZaI) described later, or a cation represented by the formula (ZaII).

[0047] When each of the above groups has an ionic group as a substituent, in the onium salt compound (N) represented by the above general formula (N-1), the total valence of the anion part and the total valence of the cation part are the same.

[0048] Each substituent may, if possible, be further substituted with the above-mentioned substituents.

[0049] Further, the number of carbon atoms of the organic group W is, for example, 1 to 20. Further, the number of atoms other than hydrogen atoms of the organic group W is, for example, 1 to 30.

[0050] Further, the number of carbon atoms of the alkyl group exemplified in the organic group W is preferably 1 to 20, more preferably 1 to 10, and still more preferably 1 to 6. The alkyl group may be either linear or branched. Examples of the alkyl group include linear or branched alkyl groups such as methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, t-butyl group, and n-hexyl group. In the alkyl group which may have a substituent, the substituent which the alkyl group may have is not particularly limited, and examples thereof include groups exemplified by the above-mentioned substituent T.

[0051] The alkyl group portion in the alkoxy group (including the alkoxy group portion in the substituent containing an alkoxy group (for example, alkoxycarbonyloxy group)) exemplified in the organic group W, the alkyl group portion in the aralkyl group, the alkyl group portion in the alkylcarbonyl group, the alkyl group portion in the alkylcarbonyloxy group, the alkyl group portion in the alkylthio group, the alkyl group portion in the alkylsulfinyl group, and the alkyl group portion in the alkylsulfonyl group are preferably the above alkyl group. Further, in the alkoxy group which may have a substituent, the aralkyl group which may have a substituent, the alkylcarbonyloxy group which may have a substituent, the alkylthio group which may have a substituent, the alkylsulfinyl group which may have a substituent, and the alkylsulfonyl group which may have a substituent, examples of the substituent which the alkoxy group, the aralkyl group, the alkylcarbonyloxy group, the alkylthio group, the alkylsulfinyl group, and the alkylsulfonyl group may have are the same as the examples of the substituent in the alkyl group which may have a substituent.

[0052] Examples of cycloalkyl groups exemplified by the organic group W include monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl groups, and polycyclic cycloalkyl groups such as norbornyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups. The number of carbon atoms in the above cycloalkyl groups is preferably 5 to 20, and more preferably 5 to 15. In cycloalkyl groups that may have substituents, examples of substituents that may be present in cycloalkyl groups are the same as those for substituents in alkyl groups that may have substituents.

[0053] The alkenyl group exemplified in organic group W may be linear or branched. The number of carbon atoms in the alkenyl group is preferably 2 to 20. In an alkenyl group that may have substituents, examples of substituents that the alkenyl group may have are similar to those of substituents in an alkyl group that may have substituents. The number of carbon atoms in the cycloalkenyl group exemplified in organic group W is preferably 5 to 20. In an alkenyl group that may have substituents, examples of substituents that the cycloalkenyl group may have are similar to those of substituents in an alkyl group that may have substituents.

[0054] The alkynyl group exemplified in organic group W may be linear or branched. The number of carbon atoms in the alkynyl group is preferably 2 to 20. In an alkynyl group which may have substituents, examples of substituents that the alkynyl group may have are the same as those for substituents in an alkyl group which may have substituents. The number of carbon atoms in the cycloalkynyl group exemplified in organic group W is preferably 5 to 20. In an cycloalkynyl group which may have substituents, examples of substituents that the cycloalkynyl group may have are the same as those for substituents in an alkyl group which may have substituents.

[0055] Unless otherwise specified, the aryl group exemplified in organic group W may be monocyclic or polycyclic (e.g., 2 to 6 rings). The number of ring member atoms of the aryl group is preferably 6 to 15, and more preferably 6 to 10. The aryl group is preferably a phenyl group, a naphthyl group, or anthryl group, and more preferably a phenyl group. In an aryl group that may have substituents, examples of substituents that the aryl group may have are the same as those for substituents in alkyl groups that may have substituents. Furthermore, among the groups exemplified in organic group W, examples of aryl group portions in substituents containing an aryl group (e.g., an aryloxy group) are the same as those for the aryl group exemplified in organic group W.

[0056] The heteroaryl group exemplified in organic group W may be monocyclic or polycyclic (e.g., 2 to 6 rings) unless otherwise specified. The number of heteroatoms that the heteroaryl group has as ring member atoms is, for example, 1 to 10. Examples of the above heteroatoms include nitrogen, sulfur, oxygen, selenium, tellurium, phosphorus, silicon, and boron. The number of ring member atoms of the above heteroaryl group is preferably 5 to 15. In a heteroaryl group that may have substituents, examples of substituents that the heteroaryl group may have are the same as those for substituents in an alkyl group that may have substituents.

[0057] The heterocycle exemplified in organic group W refers to a ring containing heteroatoms as ring member atoms, and unless otherwise specified, it may be either an aromatic heterocycle or an aliphatic heterocycle, and may be either a monocycle or a polycycle (e.g., 2 to 6 rings). The number of heteroatoms that the heterocycle has as ring member atoms is, for example, 1 to 10. Examples of the above heteroatoms include nitrogen, sulfur, oxygen, selenium, tellurium, phosphorus, silicon, and boron atoms. The number of ring member atoms of the above heterocycle is preferably 5 to 15. In a heterocycle that may have substituents, examples of substituents that the heterocycle may have are the same as those for substituents in alkyl groups that may have substituents.

[0058] The lactone group exemplified in organic group W is preferably a 5- to 7-membered ring lactone group, and more preferably one in which another ring structure is fused to the 5- to 7-membered ring lactone ring in a bicyclo or spiro structure. In the lactone group which may have substituents, examples of substituents that may be present on the lactone group are the same as those for substituents in alkyl groups which may have substituents.

[0059] R １ and R ２ Preferably, R is a hydrogen atom, alkyl group, cycloalkyl group, alkoxy group or aryl group. １ and R ２ Preferably, at least one of them is a hydrogen atom. The presence of at least one hydrogen atom allows -CO to bond to Ar. ２ － The nucleophilicity of the resist is further reduced, and the temporal stability of the resist composition is improved, thereby further suppressing the sensitivity fluctuations of the pattern due to the storage of the composition over time.

[0060] In the general formula (N-1), X is -CO ２ － , -SO ２ NR １ R ２ It represents a monovalent substituent other than X. The monovalent substituent represented by X is not particularly limited, but may include a halogen atom, a hydroxyl group, or a monovalent organic group.

[0061] Examples of halogen atoms represented by X include fluorine, chlorine, bromine, and iodine atoms, with fluorine or iodine atoms being preferred.

[0062] The monovalent organic group represented by X is not particularly limited, and examples include the group exemplified by the organic group W above.

[0063] In particular, X represents a halogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, or a cycloalkoxycarbonyl group.

[0064] When the resist composition of the present invention is used as a resist for EUV, it is preferable that at least one of X contains a halogen atom, and it is more preferable that it contains a fluorine atom or an iodine atom.

[0065] In the general formula (N-1), m represents an integer of 0 or more, preferably an integer of 0 to 4, and more preferably an integer of 0 to 2.

[0066] In the general formula (N-1), n represents an integer of 1 or more, preferably an integer of 1 to 4, and more preferably 1 or 2.

[0067] In the general formula (N-1), r represents an integer of 1 or more, preferably an integer of 1 to 2, and more preferably 1.

[0068] In the general formula (N-1), Ma ｐ＋ represents a p-valent onium cation. p and q each independently represent an integer of 1 or more. However, p×q = r is satisfied. It is preferable that both p and q are 1. That is, Ma ｐ＋ is preferably a monovalent onium cation.

[0069] Ma ｐ＋ As the onium cation represented by Ma, the cation represented by the following formula (ZaI) or the cation represented by the formula (ZaIi) is preferable.

[0070] When the resist composition of the present invention is used as a resist for EUV, Ma ｐ＋ preferably contains a halogen atom, and more preferably contains a fluorine atom or an iodine atom.

[0071] In the general formula (N-1), -CO ２ － and -SO ２ NR １ R ２ are preferably bonded to the same ring in Ar. That is, for example, when Ar represents a polycyclic ring, -CO ２ － is bonded to the same ring as the ring to which -SO ２ NR １ R ２It is preferable that at least one of them is bonded. Also, -CO ２ － To a ring member atom adjacent to the ring member atom in Ar to which is bonded, -SO ２ NR １ R ２ It is preferable that at least one of them is bonded. When -SO ２ NR １ R ２ is bonded to an adjacent ring member atom, the nucleophilicity of -CO ２ － is further reduced, and the stability over time of the resist composition is improved. Therefore, it is possible to further suppress the sensitivity variation of the pattern due to the storage of the composition over time. The above ring member atom is preferably a carbon atom.

[0072] The onium salt compound (N) represented by the general formula (N-1) is more preferably represented by the following general formula (N-2).

[0073]

[0074] In the general formula (N-2), R １ and R ２ each independently represent a hydrogen atom, a halogen atom, or a monovalent organic group. X represents a monovalent substituent other than -CO ２ － , -SO ２ NR １ R ２ . m2 represents an integer of 0 to 2. When m is an integer of 2 or more, the plurality of Xs may be the same or different, and the plurality of Xs may be linked to form a ring. n2 represents 1 or 2. When n is 2, the plurality of R １ and R ２ may each be the same or different. Ma ＋ represents a monovalent onium cation.

[0075] R １ , R ２ and X in the general formula (N-2) are respectively synonymous with R １ , R ２ and X in the above general formula (N-1), and the preferred examples are also the same. Ma ＋As the monovalent onium cation represented by [it], a cation represented by the following formula (ZaI) or a cation represented by the formula (ZaII) is preferable.

[0076] The onium salt compound (N) represented by the general formula (N-1) is more preferably represented by the following general formula (N-3).

[0077]

[0078] In the general formula (N-3), R １ and R ２ each independently represents a hydrogen atom, a halogen atom, or a monovalent organic group. X represents a monovalent substituent other than -CO ２ － , -SO ２ NR １ R ２ . m2 represents an integer of 0 to 2. When m is an integer of 2 or more, a plurality of Xs may be the same or different, and a plurality of Xs may be linked to form a ring. Ma ＋ represents a monovalent onium cation.

[0079] R １ , R ２ , X, m2, and Ma ＋ in the general formula (N-3) are respectively synonymous with R １ , R ２ , X, m2, and Ma ＋ in the general formula (N-2), and the preferred examples are also the same.

[0080] Specific examples of the onium salt compound (N) include the onium salt compounds (I)-1 to (I)-30 described in the examples below, but the present invention is not limited thereto.

[0081] The content of the onium salt compound (N) is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and even more preferably 5.0% by mass or more, based on the total solid content of the resist composition. Furthermore, the content of the onium salt compound (N) is preferably 50.0% by mass or less, more preferably 45.0% by mass or less, and even more preferably 40.0% by mass or less, based on the total solid content of the resist composition. The onium salt compound (N) may be used alone or in combination of two or more types. When using two or more types, it is preferable that their total content is within the range of the above preferred content.

[0082] [Photoacid Generator] The resist composition may contain a photoacid generator. The photoacid generator is not particularly limited as long as it is a compound that generates acid upon irradiation with active light or radiation (hereinafter also simply referred to as "exposure"), but is a compound other than the above compound (N). The photoacid generator preferably generates an acid with a pKa of less than 0 upon exposure. The pKa of the acid generated from the photoacid generator upon exposure is preferably -0.1 or less, and more preferably -0.5 or less. Furthermore, the pKa of the acid generated from the photoacid generator upon exposure is preferably -5.0 or more, and more preferably -4.5 or more.

[0083] The photoacid generator may be in the form of a low molecular weight compound, or it may be incorporated into a part of the resin. Alternatively, both the low molecular weight compound form and the form incorporated into a part of the resin may be used in combination. The photoacid generator is preferably in the form of a low molecular weight compound. When the photoacid generator is in the form of a low molecular weight compound, its molecular weight is not particularly limited, but it is preferably 500 to 3000, more preferably 600 to 2500, and even more preferably 700 to 2000. When the photoacid generator is incorporated into a part of the resin, it may be incorporated into a part of an acid-degradable resin, or into a resin different from the acid-degradable resin.

[0084] Examples of photoacid generators include, "M ＋ X －Examples of compounds represented by '' (onium salts) include compounds that generate organic acids upon exposure. Examples of organic acids include sulfonic acids (aliphatic sulfonic acids, aromatic sulfonic acids, and camphor sulfonic acids, etc.), carboxylic acids (aliphatic carboxylic acids, aromatic carboxylic acids, and aralkyl carboxylic acids, etc.), carbonylsulfonylimide acid, bis(alkylsulfonyl)imide acid, and tris(alkylsulfonyl)methidic acid.

[0085] "M ＋ X － In the compound represented by ", M ＋ The symbol represents a cation, preferably an organic cation. The valency of the cation may be monovalent or divalent or higher. The cation is preferably a cation represented by formula (ZaI) (hereinafter also referred to as "cation (ZaI)") or a cation represented by formula (ZaII) (hereinafter also referred to as "cation (ZaII)").

[0086]

[0087] In the above formula (ZaI), R ２０１ , R ２０２ , and R ２０３ Each of these independently represents an organic group. ２０１ , R ２０２ , and R ２０３ The number of carbon atoms in the organic group is preferably 1 to 30, and more preferably 1 to 20. ２０１ ~R ２０３ Two of these may bond to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester group, an amide group, or a carbonyl group. ２０１ ~R ２０３ Examples of groups formed by the bonding of two of these include alkylene groups (e.g., butylene and pentylene groups) and -CH ２ -CH ２ -O-CH ２ -CH ２ - is an example. When the resist composition of the present invention is used as an EUV resist, R ２０１ ~R ２０５Preferably, the cation contains a fluorine atom or an iodine atom as a substituent. Preferred embodiments of the cation represented by formula (ZaI) include cation (ZaI-1), cation (ZaI-2), cation (ZaI-3b), and cation (ZaI-4b), which will be described later.

[0088] First, let's explain the cation (ZaI-1). The cation (ZaI-1) is R in the above formula (ZaI). ２０１ ~R ２０３ It is an arylsulfonium cation in which at least one of the groups is an aryl group. ２０１ ~R ２０３ All of them may be aryl groups, or R ２０１ ~R ２０３ A portion of it may be an aryl group, and the remainder may be an alkyl group or a cycloalkyl group. ２０１ ~R ２０３ One of them is an aryl group, R ２０１ ~R ２０３ The remaining two of these may bond to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester group, an amide group, or a carbonyl group. ２０１ ~R ２０３ Examples of groups formed by the bonding of two of these include alkylene groups in which one or more methylene groups may be substituted with an oxygen atom, a sulfur atom, an ester group, an amide group, and / or a carbonyl group (e.g., butylene group, pentylene group, and -CH ２ -CH ２ -O-CH ２ -CH ２ Examples of arylsulfonium cations include triarylsulfonium cation, diarylalkylsulfonium cation, diarylcycloalkylsulfonium cation, aryldialkylsulfonium cation, and aryldicycloalkylsulfonium cation.

[0089] The aryl group contained in the arylsulfonium cation is preferably a phenyl group or a naphthyl group, with the phenyl group being more preferred. When the arylsulfonium cation has two or more aryl groups, the two or more aryl groups may be the same or different. The aryl group may be an aryl group having a heterocyclic structure containing an oxygen atom, a nitrogen atom, or a sulfur atom, etc. Examples of heterocyclic structures include pyrrole residues, furan residues, thiophene residues, indole residues, benzofuran residues, and benzothiophene residues. The alkyl or cycloalkyl group that the arylsulfonium cation may have is preferably a linear alkyl group having 1 to 15 carbon atoms, a branched alkyl group having 3 to 15 carbon atoms, or a cycloalkyl group having 3 to 15 carbon atoms, with methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, t-butyl group, cyclopropyl group, cyclobutyl group, or cyclohexyl group being more preferred.

[0090] The above aryl group may have substituents, and preferred substituents are alkyl groups (e.g., C1-C15), cycloalkyl groups (e.g., C3-C15), aryl groups (e.g., C6-C14), alkoxy groups (e.g., C1-C15), cycloalkylalkoxy groups (e.g., C1-C15), halogen atoms (e.g., fluorine and iodine), hydroxyl groups, carboxyl groups, ester groups, sulfinyl groups, sulfonyl groups, alkylthio groups, phenylthio groups, or alkyloxycarbonylalkyleneoxy groups. The above substituents may have further substituents if possible, and it is also preferable that the alkyl group has a halogen atom as a substituent to form a halogenated alkyl group such as a trifluoromethyl group. It is also preferable that the above substituents form an acid-degradable group in any combination. An acid-degradable group is a group that decomposes and increases in polarity upon the action of an acid, and it is preferable that the polar group is protected by a group that is eliminated upon the action of an acid.

[0091] Next, we will explain the cation (ZaI-2). The cation (ZaI-2) is R in formula (ZaI). ２０１ ~R ２０３However, each of these independently represents a cation that does not have an aromatic ring. The term "aromatic ring" also includes aromatic rings containing heteroatoms. R ２０１ ~R ２０３ The number of carbon atoms in the organic group that does not have an aromatic ring is preferably 1 to 30, and more preferably 1 to 20. ２０１ ~R ２０３ The preferred members are, independently, alkyl groups, cycloalkyl groups, allyl groups, or vinyl groups, more preferably linear or branched 2-oxoalkyl groups, 2-oxocycloalkyl groups, or alkoxycarbonylmethyl groups, and even more preferably linear or branched 2-oxoalkyl groups.

[0092] R ２０１ ~R ２０３ Examples of alkyl and cycloalkyl groups represented by include linear alkyl groups having 1 to 10 carbon atoms or branched alkyl groups having 3 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, and pentyl group), and cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl group, cyclohexyl group, and norbornyl group). ２０１ ~R ２０３ This may be further substituted with a halogen atom, an alkoxy group (e.g., having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

[0093] Next, we will explain the cation (ZaI-3b). The cation (ZaI-3b) is a cation represented by the following formula (ZaI-3b).

[0094]

[0095] In formula (ZaI-3b), R １ｃ ~R ５ｃ Each of these independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a cycloalkylcarbonyloxy group, a halogen atom, a hydroxyl group, a nitro group, an alkylthio group, or an arylthio group. ６ｃ and R ７ｃEach of these independently represents a hydrogen atom, an alkyl group (e.g., a t-butyl group), a cycloalkyl group, a halogen atom, a cyano group, or an aryl group. ｘ and R ｙ Each of these independently represents an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, an allyl group, or a vinyl group.

[0096] R １ｃ ~R ５ｃ Two or more of the following, R ５ｃ and R ６ｃ , R ６ｃ and R ７ｃ , R ５ｃ and R ｘ , and R ｘ and R ｙ These elements may be bonded to each other to form a ring, and each of these rings may independently contain an oxygen atom, a sulfur atom, a ketone group, an ester bond, or an amide bond. Examples of the above rings include aromatic or non-aromatic hydrocarbon rings, aromatic or non-aromatic heterorings, and polycyclic fused rings formed by the combination of two or more of these rings. Examples of rings include 3 to 10-membered rings, 4 to 8-membered rings are preferred, and 5 or 6-membered rings are more preferred.

[0097] R １ｃ ~R ５ｃ Two or more of the following, R ６ｃ and R ７ｃ , and R ｘ and R ｙ Examples of groups formed by the bonding include alkylene groups such as butylene and pentylene groups. The methylene group in the alkylene group may be substituted with a heteroatom such as an oxygen atom. ５ｃ and R ６ｃ , and R ５ｃ and R ｘ The groups formed by the bonding of these elements are preferably single bonds or alkylene groups. Examples of alkylene groups include methylene groups and ethylene groups.

[0098] R １ｃ ~R ５ｃ , R ６ｃ , R ７ｃ , R ｘ , Rｙ , and R １ｃ ~R ５ｃ Two or more of the following, R ５ｃ and R ６ｃ , R ６ｃ and R ７ｃ , R ５ｃ and R ｘ , and R ｘ and R ｙ The rings formed by the bonding of these elements to each other may have substituents.

[0099] Next, we will explain the cation (ZaI-4b). The cation (ZaI-4b) is a cation represented by the following formula (ZaI-4b).

[0100]

[0101] In equation (ZaI-4b), l represents an integer from 0 to 2, and r represents an integer from 0 to 8. １３ R represents a group containing a hydrogen atom, a halogen atom (e.g., a fluorine atom and an iodine atom), a hydroxyl group, an alkyl group, an alkyl halide, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, or a cycloalkyl group (which may be a cycloalkyl group itself or a group containing a cycloalkyl group as part). These groups may have substituents. １４ R represents a hydroxyl group, a halogen atom (e.g., a fluorine atom and an iodine atom), an alkyl group, an alkyl halide, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, a cycloalkylsulfonyl group, or a group containing a cycloalkyl group (which may be a cycloalkyl group itself or a group containing a cycloalkyl group in part). These groups may have substituents. １４ The fields in which multiple instances exist may be independent or distinct from each other. １５ Each of these independently represents an alkyl group, a cycloalkyl group, or a naphthyl group. １５ They may bond to each other to form a ring. Two R １５ When these atoms bond to each other to form a ring, the ring may contain heteroatoms such as oxygen atoms or nitrogen atoms. In one embodiment, two R１５ It is preferable that the alkyl group is an alkylene group and that they bond to each other to form a ring structure. The alkyl group, cycloalkyl group and naphthyl group and the two R １５ The ring formed by the bonding of these elements may have substituents.

[0102] In formula (ZaI-4b), R １３ , R １４ and R １５ The alkyl group may be linear or branched. The alkyl group preferably has 1 to 10 carbon atoms. The alkyl group is preferably a methyl group, ethyl group, n-butyl group, or t-butyl group.

[0103] Next, we will explain equation (ZaII). In equation (ZaII), R ２０４ and R ２０５ Each of these independently represents an aryl group, an alkyl group, or a cycloalkyl group. ２０４ and R ２０５ The aryl group is preferably a phenyl group or a naphthyl group, with the phenyl group being more preferred. Alternatively, it may be an aryl group having a heterocycle containing an oxygen atom, a nitrogen atom, or a sulfur atom. Examples of heterocycle aryl group skeletons include pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene. ２０４ and R ２０５ The alkyl and cycloalkyl groups are preferably linear alkyl groups having 1 to 10 carbon atoms, branched alkyl groups having 3 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, or pentyl group), or cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl group, cyclohexyl group, or norbornyl group).

[0104] R ２０４ and R ２０５ The aryl group, alkyl group, and cycloalkyl group may each independently have substituents. ２０４ and R ２０５Examples of substituents that the aryl group, alkyl group, and cycloalkyl group may have include alkyl groups (e.g., having 1 to 15 carbon atoms), cycloalkyl groups (e.g., having 3 to 15 carbon atoms), aryl groups (e.g., having 6 to 15 carbon atoms), alkoxy groups (e.g., having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, and phenylthio groups.

[0105] Specific examples of organic cations are shown below, but the present invention is not limited thereto.

[0106]

[0107]

[0108] "M ＋ X － In the compound represented by ", X － The symbol represents an anion, preferably an organic anion. The valency of the anion may be monovalent or divalent or greater. The anion is preferably one with a remarkably low ability to undergo nucleophilic reactions, and more preferably a non-nucleophilic anion. The organic anion may be used alone or in combination of two or more.

[0109] Examples of non-nucleophilic anions include sulfonate anions (aliphatic sulfonate anions, aromatic sulfonate anions, and camphor sulfonate anions, etc.), carboxylic acid anions (aliphatic carboxylic acid anions, aromatic carboxylic acid anions, and aralkyl carboxylic acid anions, etc.), sulfonylimide anions, bis(alkylsulfonyl)imide anions, and tris(alkylsulfonyl)methide anions.

[0110] The aliphatic moiety in aliphatic sulfonic acid anions and aliphatic carboxylic acid anions may be a linear or branched alkyl group or a cycloalkyl group, with linear or branched alkyl groups having 1 to 30 carbon atoms or cycloalkyl groups having 3 to 30 carbon atoms being preferred. The alkyl group may be, for example, a fluoroalkyl group (which may have substituents other than fluorine atoms; it may also be a perfluoroalkyl group).

[0111] In aromatic sulfonic acid anions and aromatic carboxylic acid anions, aryl groups having 6 to 14 carbon atoms are preferred, such as phenyl groups, tolyl groups, and naphthyl groups.

[0112] The alkyl groups, cycloalkyl groups, and aryl groups listed above may have substituents. Examples of substituents include nitro groups, halogen atoms such as fluorine and chlorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably having 1 to 15 carbon atoms), alkyl groups (preferably having 1 to 10 carbon atoms), cycloalkyl groups (preferably having 3 to 15 carbon atoms), aryl groups (preferably having 6 to 14 carbon atoms), alkoxycarbonyl groups (preferably having 2 to 7 carbon atoms), acyl groups (preferably having 2 to 12 carbon atoms), alkoxycarbonyloxy groups (preferably having 2 to 7 carbon atoms), alkylthio groups (preferably having 1 to 15 carbon atoms), alkylsulfonyl groups (preferably having 1 to 15 carbon atoms), alkyliminosulfonyl groups (preferably having 1 to 15 carbon atoms), and aryloxysulfonyl groups (preferably having 6 to 20 carbon atoms). When the resist composition of the present invention is used as an EUV resist, it is also preferable, and more preferable, to include a fluorine atom or an iodine atom as a substituent. There is no limit to the number of fluorine or iodine atoms, but from the viewpoint of EUV light absorption efficiency, the more the better.

[0113] In aralkyl carboxylate anions, aralkyl groups having 7 to 14 carbon atoms are preferred. Examples of aralkyl groups having 7 to 14 carbon atoms include benzyl, phenethyl, naphthylmethyl, naphthylethyl, and naphthylbutyl groups.

[0114] An example of a sulfonylimid anion is the saccharin anion.

[0115] In bis(alkylsulfonyl)imido anions and tris(alkylsulfonyl)methide anions, alkyl groups having 1 to 5 carbon atoms are preferred. Substituents for these alkyl groups include halogen atoms, halogen-substituted alkyl groups, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, and cycloalkylaryloxysulfonyl groups, with fluorine atoms or fluorine-substituted alkyl groups being preferred. Furthermore, the alkyl groups in bis(alkylsulfonyl)imido anions may be bonded to each other to form a ring structure.

[0116] Other non-nucleophilic anions include, for example, fluorinated phosphorus (e.g., PF). ６ － ), fluorinated boron (for example, BF ４ － ), and fluorinated antimony (e.g., SbF ６ － ) are some examples.

[0117] Preferred non-nucleophilic anions include aliphatic sulfonic acid anions in which at least the α-position of the sulfonic acid is substituted with a fluorine atom, aromatic sulfonic acid anions substituted with a fluorine atom or a group containing a fluorine atom, bis(alkylsulfonyl)imide anions in which the alkyl group is substituted with a fluorine atom, or tris(alkylsulfonyl)methide anions in which the alkyl group is substituted with a fluorine atom. Among these, perfluoroaliphatic sulfonic acid anions (preferably having 4 to 8 carbon atoms) or benzenesulfonic acid anions containing a fluorine atom are more preferred, and nonafluorobutanesulfonic acid anions, perfluorooctanesulfonic acid anions, pentafluorobenzenesulfonic acid anions, or 3,5-bis(trifluoromethyl)benzenesulfonic acid anions are even more preferred.

[0118] As a non-nucleophilic anion, the anion represented by the following formula (AN1) is also preferred.

[0119]

[0120] In formula (AN1), R １ and R２ Each of these independently represents a hydrogen atom or a substituent. The substituent is not particularly limited, but groups that are not electron-withdrawing groups are preferred. Examples of groups that are not electron-withdrawing groups include hydrocarbon groups, hydroxyl groups, oxy hydrocarbon groups, oxycarbonyl hydrocarbon groups, amino groups, hydrocarbon-substituted amino groups, and hydrocarbon-substituted amide groups, and include -R', -OH, -OR', -OCOR', -NH ２ ,-NR' ２ , -NHR', or -NHCOR' are preferred. R' is a monovalent hydrocarbon group. Among them, R １ and R ２ Each of these is independently preferably a hydrocarbon group (cycloalkyl group is preferred) or a hydrogen atom.

[0121] Examples of monovalent hydrocarbon groups represented by R' above include alkyl groups such as methyl, ethyl, propyl, and butyl groups; alkenyl groups such as ethenyl, propenyl, and butenyl groups; monovalent linear or branched hydrocarbon groups such as alkynyl groups such as ethynyl, propynyl, and butynyl groups; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornyl, and adamantyl groups; monovalent alicyclic hydrocarbon groups such as cyclopropenyl, cyclobutenyl, cyclopentenyl, and norbornenyl groups; aryl groups such as phenyl, tolyl, xylyl, mesityl, naphthyl, methylnaphthyl, anthryl, and methylanthryl groups; and monovalent aromatic hydrocarbon groups such as benzyl, phenethyl, phenylpropyl, naphthylmethyl, and anthrylmethyl groups.

[0122] L represents a divalent linking group. Examples of divalent linking groups include -O-CO-O-, -COO-, -CONH-, -CO-, -O-, -S-, -SO-, and -SO ２Examples of divalent linking groups include alkylene groups (preferably having 1 to 6 carbon atoms), cycloalkylene groups (preferably having 3 to 15 carbon atoms), alkenylene groups (preferably having 2 to 6 carbon atoms), and divalent linking groups formed by combining multiples thereof. Among these, examples of divalent linking groups include -O-CO-O-, -COO-, -CONH-, -CO-, -O-, and -SO ２ -, -O-CO-O-alkylene group-, -COO-alkylene group-, or -CONH-alkylene group- are preferred, and -O-CO-O-, -O-CO-O-alkylene group-, -COO-, -CONH-, -SO ２ - or -COO-alkylene group- is more preferred.

[0123] For L, a group represented by the following formula (AN1-1) is preferred. * ａ - (CR ２ａ ２ ) Ｘ -Q- (CR ２ｂ ２ ) Ｙ - * ｂ (AN1-1)

[0124] In formula (AN1-1), * ａ R in equation (AN1) ３ This indicates the connection point with [the other element]. ｂ This is -C(R) in equation (AN1). １ ) (Caution ２ ) - Represents the connection position with . X and Y each independently represent integers from 0 to 10, preferably integers from 0 to 3. R ２ａ and R ２ｂ Each of these independently represents a hydrogen atom or a substituent. ２ａ and R ２ｂ If there are multiple instances of each, then there are multiple instances of R ２ａ and R ２ｂ These may be the same or different. However, if Y is 1 or greater, -C(R) in equation (AN1) １ ) (Caution ２ )- and CR that bind directly ２ｂ ２ In R ２ｂ is anything other than a fluorine atom. Q is * Ａ -O-CO-O-*Ｂ , * Ａ -CO-* Ｂ , * Ａ -CO-O-* Ｂ , * Ａ -O-CO-* Ｂ , * Ａ -O-* Ｂ , * Ａ -S-* Ｂ , or, * Ａ -SO ２ - * Ｂ This represents the condition that X+Y in equation (AN1-1) is 1 or greater, and R in equation (AN1-1) is greater than or equal to 1. ２ａ and R ２ｂ If all of them are hydrogen atoms, then Q is * Ａ -O-CO-O-* Ｂ , * Ａ -CO-* Ｂ , * Ａ -O-CO-* Ｂ , * Ａ -O-* Ｂ , * Ａ -S-* Ｂ , or, * Ａ -SO ２ - * Ｂ This represents. * Ａ R in equation (AN1) ３ This indicates the connection position on the side, * Ｂ This is -SO in equation (AN1). ３ － This indicates the connection point on the side.

[0125] In formula (AN1), R ３ R represents an organic group. The above organic group is not particularly limited and may be a linear group (e.g., a linear alkyl group), a branched group (e.g., a branched alkyl group such as a t-butyl group), or a cyclic group. The above organic group may have substituents and may have heteroatoms (oxygen atom, sulfur atom, and / or nitrogen atom, etc.). Among these, R ３It is preferable that the organic group has a cyclic structure. The cyclic structure may be monocyclic or polycyclic and may have substituents. It is preferable that the ring in the organic group containing the cyclic structure is directly bonded to L in formula (AN1). The organic group having the cyclic structure may have, for example, heteroatoms (oxygen atom, sulfur atom, and / or nitrogen atom). The heteroatoms may be substituted for one or more carbon atoms forming the cyclic structure.

[0126] The organic group having the above-mentioned cyclic structure is preferably a cyclic hydrocarbon group, a lactone ring group, or a sultone ring group, with a cyclic hydrocarbon group being more preferred. The above-mentioned cyclic hydrocarbon group is preferably a monocyclic or polycyclic cycloalkyl group. These groups may have substituents. The above-mentioned cycloalkyl group may be monocyclic (e.g., a cyclohexyl group) or polycyclic (e.g., an adamantyl group), and the number of carbon atoms is preferably 5 to 12.

[0127] R ３ It is preferable that it contains a halogen atom. ３ The halogen atoms included are preferably fluorine atoms or iodine atoms, with iodine atoms being more preferred. If iodine atoms are present, a structure in which they are directly bonded to carbon atoms on the aromatic ring is preferred. When the resist composition of the present invention is used as an EUV resist, a larger number of halogen atoms is preferable from the viewpoint of EUV light absorption efficiency.

[0128] Examples of anions represented by formula (AN1) include those described in

[0040] to

[0044] of Japanese Patent Publication No. 2018-155908,

[0184] to

[0185] and

[0197] to

[0198] of Japanese Patent Publication No. 2021-128331,

[0124] to

[0125] and

[0137] to

[0138] of International Publication No. 2022 / 064863, and

[0056] to

[0061] of Japanese Patent Publication No. 2023-177048, the above descriptions are incorporated herein by reference.

[0129] As a non-nucleophilic anion, the anion represented by the following formula (AN2) is also preferred.

[0130]

[0131] In formula (AN2), o represents an integer from 1 to 3. p represents an integer from 0 to 10. q represents an integer from 0 to 10. L represents a divalent linking group. The definition of L is the same as that of L in formula (AN1).

[0132] Xf represents a hydrogen atom, a fluorine atom, an alkyl group substituted with one or more fluorine atoms, or an organic group without a fluorine atom. The number of carbon atoms in this alkyl group is preferably 1 to 10, more preferably 1 to 4. As the alkyl group substituted with one or more fluorine atoms, a perfluoroalkyl group is preferred. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, and fluorine atom or CF ３ It is more preferable that all Xf are fluorine atoms, and even more preferable that all Xf are fluorine atoms.

[0133] R ４ and R ５ Each of these independently represents a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with one or more fluorine atoms. ４ and R ５ If multiple instances exist, R ４ and R ５ These may be the same or different. ４ and R ５ The alkyl group represented by preferably has 1 to 4 carbon atoms. The alkyl group may have substituents. ４ and R ５ A hydrogen atom is preferred as the element.

[0134] W represents an organic group containing a cyclic structure. Among these, a cyclic organic group is preferred. The carbon atoms constituting the cyclic organic group (carbon atoms contributing to ring formation) may be carbonyl carbons. Examples of cyclic organic groups include alicyclic groups, aryl groups, and heterocyclic groups. Alicyclic groups may be monocyclic or polycyclic. Examples of monocyclic alicyclic groups include monocyclic cycloalkyl groups such as cyclopentyl groups, cyclohexyl groups, and cyclooctyl groups. Examples of polycyclic alicyclic groups include polycyclic cycloalkyl groups such as norbornyl groups, tricyclodecanyl groups, tetracyclodecanyl groups, tetracyclododecanyl groups, and adamantyl groups. Among these, alicyclic groups having a bulky structure with 7 or more carbon atoms, such as norbornyl groups, tricyclodecanyl groups, tetracyclodecanyl groups, tetracyclododecanyl groups, and adamantyl groups, are preferred.

[0135] The aryl group may be monocyclic or polycyclic. Examples of the above aryl group include the phenyl group, naphthyl group, phenanthryl group, and anthryl group. The heterocyclic group may be monocyclic or polycyclic. The heterocyclic group may or may not be aromatic. Examples of aromatic heterocyclic rings include the furan ring, thiophene ring, benzofuran ring, benzothiophene ring, dibenzofuran ring, dibenzothiophene ring, and pyridine ring. Examples of heterocyclic rings that are not aromatic include the tetrahydropyran ring, lactone ring, sultone ring, and decahydroisoquinoline ring. The heterocyclic ring in the heterocyclic group is preferably a furan ring, thiophene ring, pyridine ring, or decahydroisoquinoline ring.

[0136] The above-mentioned cyclic organic group may have substituents. Examples of substituents include alkyl groups (which may be linear or branched, preferably having 1 to 12 carbon atoms), cycloalkyl groups (which may be monocyclic, polycyclic, or spirocyclic, preferably having 3 to 20 carbon atoms), aryl groups (preferably having 6 to 14 carbon atoms), hydroxyl groups, alkoxy groups, ester groups, amide groups, urethane groups, ureido groups, thioether groups, sulfonamide groups, and sulfonic acid ester groups.

[0137] It is preferable that W contains halogen atoms. Preferably, the halogen atoms in W are fluorine atoms or iodine atoms, with iodine atoms being more preferable. If iodine atoms are present, a structure in which they are directly bonded to carbon atoms on an aromatic ring is preferred. When the resist composition of the present invention is used as an EUV resist, a larger number of halogen atoms is preferable from the viewpoint of EUV light absorption efficiency.

[0138] Anions represented by formula (AN2) include SO ３ － -CF ２ -CH ２ -OCO-(L) ｑ’ -W, SO ３ － -CF ２ -CHF-CH ２ -OCO-(L) ｑ’ -W, SO ３ － -CF ２ -COO-(L) ｑ’ -W, SO ３ － -CF ２ -CF ２ -CH ２ -CH ２ - (L) ｑ -W, or SO ３ － -CF ２ -CH(CF ３ )-OCO-(L) ｑ’ -W is preferred. q' represents an integer from 0 to 10. L, q, and W are the same as in formula (AN2).

[0139] Anions represented by formula (AN2) include

[0076] in International Publication No. 2023 / 157455,

[0071] to

[0089] in Japanese Patent Publication No. 2021-081708,

[0033] to

[0045] in Japanese Patent Publication No. 2018-005224,

[0031] to

[0039] in Japanese Patent Publication No. 2018-025789, and Japanese Patent Publication No. 2021 Examples include the anions described in

[0176] to

[0183] and

[0186] to

[0196] of Publication No. 128331,

[0116] to

[0123] and

[0126] to

[0136] of International Publication No. 2022 / 064863, and

[0076] of International Publication No. 2023 / 157455, which are incorporated herein by reference.

[0140] As a non-nucleophilic anion, an aromatic sulfonic acid anion represented by the following formula (AN3) is also preferred.

[0141]

[0142] In formula (AN3), Ar represents an aryl group (such as a phenyl group) and may further have substituents other than a sulfonic acid anion and a -(D-B) group. Examples of further substituents include a fluorine atom and a hydroxyl group. n represents an integer of 0 or more. n is preferably 1 to 4, more preferably 2 to 3, and even more preferably 3.

[0143] D represents a single bond or a divalent linking group. Examples of divalent linking groups include ether groups, thioether groups, carbonyl groups, sulfoxide groups, sulfone groups, sulfonic acid ester groups, ester groups, and groups consisting of two or more combinations thereof.

[0144] B represents a hydrocarbon group. B is preferably an aliphatic hydrocarbon group, and more preferably an isopropyl group, a cyclohexyl group, or an aryl group which may have further substituents (such as a tricyclohexylphenyl group).

[0145] It is preferable that B contains halogen atoms. Preferably, the halogen atoms in B are fluorine atoms or iodine atoms, with iodine atoms being more preferable. If iodine atoms are present, a structure in which they are directly bonded to carbon atoms on an aromatic ring is preferred. When the resist composition is used as an EUV resist, a larger number of halogen atoms is preferable from the viewpoint of EUV light absorption efficiency.

[0146] Examples of anions represented by formula (AN3) include those described in

[0029] to

[0034] of Japanese Patent Publication No. 2018-159744,

[0045] of Japanese Patent Publication No. 2018-155908,

[0037] to

[0055] and

[0062] to

[0064] of Japanese Patent Publication No. 2023-177048, the above descriptions are incorporated herein by reference.

[0147] As a non-nucleophilic anion, disulfonamide anions are also preferred. Disulfonamide anions include, for example, N － (SO ２ -R ｑ ) ２ This is an anion represented by R. ｑ R represents an alkyl group which may have substituents, preferably a fluoroalkyl group, and more preferably a perfluoroalkyl group. ｑ They may be joined to each other to form a ring. Two R ｑ The group formed by the bonding of these atoms is preferably an alkylene group, which may have substituents, preferably a fluoroalkylene group, and more preferably a perfluoroalkylene group. The alkylene group preferably has 2 to 4 carbon atoms.

[0148] Furthermore, non-nucleophilic anions include those represented by the following formulas (d1-1) to (d1-4).

[0149]

[0150] In formula (d1-1), R ５１represents a hydrocarbon group (e.g., an aryl group such as a phenyl group) which may have substituents (e.g., a hydroxyl group). Examples of anions represented by formula (d1-1) include

[0041] to

[0047] in JP 2017-219836,

[0026] to

[0028] in JP 2018-155902,

[0040] to

[0041] and

[0128] in JP 2020-154212,

[0049] to

[0061] and

[0278] to

[0279] in JP 2021-091666, and International Publication No. 2022 / Examples of anions described in

[0150] to

[0154] of JP 064863,

[0013] to

[0015] of JP 2022-077505,

[0026] to

[0031] and

[0050] to

[0051] of JP 2022-141598,

[0147] of JP 2023-108593, and

[0088] of International Publication No. 2023 / 157455 are included, and the above descriptions are incorporated herein by reference.

[0151] In formula (d1-2), Z ２ｃ represents a hydrocarbon group having 1 to 30 carbon atoms, which may have substituents (however, carbon atoms adjacent to S are not substituted with fluorine atoms). ２ｃ The hydrocarbon group in the above may be linear, branched, or have a cyclic structure. Furthermore, the carbon atoms in the hydrocarbon group (preferably, the ring member carbon atoms when the hydrocarbon group has a cyclic structure) may be carbonyl carbons (-CO-). Examples of the hydrocarbon group include a group having a norbornyl group which may have substituents. The carbon atoms in the norbornyl group may also be carbonyl carbons.

[0152] The anion represented by formula (d1-2) is preferably different from the anions represented by formulas (AN1) to (AN3) described above. For example, Z ２ｃ A group other than an aryl group is preferred. Also, Z ２ｃ In, -SO ３ － For Z, the atoms at the α and β positions are preferably atoms other than carbon atoms that have a fluorine atom as a substituent. ２ｃ is, -SO ３ －In relation to this, the atom at the α position and / or the atom at the β position are preferably ring member atoms in the cyclic group.

[0153] In formula (d1-3), R ５２ represents an organic group (preferably a hydrocarbon group having a fluorine atom), Y ３ represents a linear, branched, or cyclic alkylene group, arylene group, or carbonyl group, and Rf represents a hydrocarbon group. Examples of anions represented by formula (d1-3) include those described in

[0040] to

[0046] of Japanese Patent Publication No. 2019-211751,

[0039] to

[0047] of Japanese Patent Publication No. 2021-128331,

[0043] to

[0060] of Japanese Patent Publication No. 2021-165824, and

[0062] and

[0075] of International Publication No. 2023 / 119910, the above descriptions are incorporated herein by reference.

[0154] In formula (d1-4), R ５３ and R ５４ Each of these independently represents an organic group (preferably a hydrocarbon group having a fluorine atom). ５３ and R ５４ They may be joined to each other to form a ring.

[0155] The photoacid generator is preferably at least one selected from the group consisting of compounds (I) to (II).

[0156] (Compound (I)) Compound (I) is a compound having one or more of the following structural sites X and one or more of the following structural sites Y, which generates an acid containing the following first acidic site derived from the following structural site X and the following second acidic site derived from the following structural site Y upon irradiation with active light or radiation. Structural site X: Anionic site A １ － and cation site M １ ＋ It consists of and is irradiated with active light or radiation, HA １ Structural site that forms the first acidic site represented by Structural site Y: Anionic site A ２ － and cation site M ２ ＋ It consists of and is irradiated with active light or radiation, HA２ The structural site (I) that forms the second acidic site represented by satisfies the following condition I.

[0157] Condition I: In the above compound (I), the above cation site M in the above structural site X. １ ＋ and the cation portion M in the structural portion Y. ２ ＋ to H ＋ The compound PI obtained by replacing the above structural site X is the cation site M １ ＋ to H ＋ HA is obtained by replacing it with １ The acid dissociation constant a1 originates from the acidic site represented by the above structure site Y, and the cation site M in the above structural site Y. ２ ＋ to H ＋ HA is obtained by replacing it with ２ It has an acid dissociation constant a2 derived from the acidic site represented by the above, and the acid dissociation constant a2 is greater than the acid dissociation constant a1.

[0158] Condition I will be explained in more detail below. If compound (I) is a compound that generates an acid having, for example, one first acidic site derived from structural site X and one second acidic site derived from structural site Y, then compound PI is "HA １ and HA ２ This falls under the category of "compounds having the above characteristics". More specifically, when the acid dissociation constants a1 and a2 of compound PI are determined, compound PI is "A １ － and HA ２ The pKa at which the compound becomes "a compound having " is the acid dissociation constant a1, and the above "A １ － and HA ２ Compounds having "A" １ － and A ２ － The pKa value at which the compound becomes "a compound having the above characteristics" is the acid dissociation constant a2.

[0159] If compound (I) is a compound that generates an acid having, for example, two first acidic sites derived from structural site X and one second acidic site derived from structural site Y, then compound PI is "two HA １ and one HA ２ This falls under the category of "compounds having one A". When the acid dissociation constant of compound PI is determined, compound PI is "a compound having one A １ － and one HA １ and one HA ２ The acid dissociation constant when a compound having " and " is formed, and " １ － and one HA １ and one HA ２ Compounds having "two A １ － and one HA ２ The acid dissociation constant when a compound having the two A's is obtained corresponds to the aforementioned acid dissociation constant a1. １ － and one HA ２ Compounds having "two A １ － and A ２ － The acid dissociation constant when a compound has the above-mentioned structure corresponds to the acid dissociation constant a2. In other words, in the case of compound PI, the above-mentioned cation site M in the above-mentioned structural site X. １ ＋ to H ＋ HA is obtained by replacing it with １ When a compound has multiple acid dissociation constants originating from the acidic site represented by , the value of acid dissociation constant a2 is greater than the largest of the multiple acid dissociation constants a1. １ － and one HA １ and one HA ２ Let aa be the acid dissociation constant when a compound having " １ － and one HA １ and one HA ２ Compounds having "two A １ － and one HA ２When the acid dissociation constant for a compound having the above is denoted as ab, the relationship between aa and ab satisfies aa < ab.

[0160] The acid dissociation constants a1 and a2 are determined by the acid dissociation constant measurement method described above. The compound PI mentioned above corresponds to the acid generated when compound (I) is irradiated with active light or radiation. If compound (I) has two or more structural sites X, the structural sites X may be the same or different. Also, two or more of the above A １ － , and two or more of the above M １ ＋ These may be the same or different. In compound (I), the above A １ － and A above ２ － , and the above M １ ＋ and the above M ２ ＋ These may be the same or different, but A above １ － and A above ２ － It is preferable that they are all different.

[0161] In the above compound PI, the difference (absolute value) between the acid dissociation constant a1 (the maximum value if there are multiple acid dissociation constants a1) and the acid dissociation constant a2 is preferably 0.1 or more, more preferably 0.5 or more, and even more preferably 1.0 or more. There is no particular upper limit to the difference (absolute value) between the acid dissociation constant a1 (the maximum value if there are multiple acid dissociation constants a1) and the acid dissociation constant a2, but for example, it is 16 or less.

[0162] In the above compound PI, the acid dissociation constant a2 is preferably 20 or less, and more preferably 15 or less. The lower limit of the acid dissociation constant a2 is preferably -4.0 or higher.

[0163] In the above compound PI, the acid dissociation constant a1 is preferably 2.0 or less, and more preferably 0 or less. The lower limit of the acid dissociation constant a1 is preferably -20.0 or higher.

[0164] Anion part A１ － and anion part A ２ － This is a structural site containing a negatively charged atom or group of atoms, and examples include structural sites selected from the group consisting of formulas (AA-1) to (AA-3) and formulas (BB-1) to (BB-6) shown below. Anion site A １ － As such, those that can form an acidic moiety with a small acid dissociation constant are preferred, and among these, those of formula (AA-1) to (AA-3) are more preferred, and those of formula (AA-1) and (AA-3) are even more preferred. Also, anion moiety A ２ － For example, Anion part A １ － It is preferable that the acidic site can form an acidic site with a larger acid dissociation constant than the above, more preferably one of formulas (BB-1) to (BB-6), and even more preferably one of formulas (BB-1) and (BB-4). In formulas (AA-1) to (AA-3) and (BB-1) to (BB-6) below, * represents the bond position. In formula (AA-2), R Ａ R represents a monovalent organic group. Ａ The monovalent organic group represented by is not particularly limited, but examples include a cyano group, a trifluoromethyl group, and a methanesulfonyl group.

[0165]

[0166]

[0167] Cation site M １ ＋ and cation site M ２ ＋ This refers to a structural site containing a positively charged atom or group of atoms, for example, a monovalent organic cation. Examples of organic cations include the aforementioned M. ＋ Examples of organic cations represented by the following are given.

[0168] (Compound (II)) Compound (II) is a compound having two or more of the above-mentioned structural sites X and one or more of the following structural sites Z, which generates an acid containing two or more of the above-mentioned first acidic sites derived from the above-mentioned structural sites X and the above-mentioned structural sites Z upon irradiation with active light or radiation. Structural site Z: A nonionic site capable of neutralizing acid

[0169] Definition of structural site X in compound (II), and A １ － and M １ ＋ The definition of is the definition of structural site X in compound (I) as described above, and A １ － and M １ ＋ This is synonymous with the definition of [the specified term], and the preferred embodiment is also the same.

[0170] In the above compound (II), the above cation moiety M in the above structural moiety X. １ ＋ to H ＋ In compound PII, which is obtained by replacing the above structural site X, the above cation site M １ ＋ to H ＋ HA is obtained by replacing it with １ The preferred range for the acid dissociation constant a1 derived from the acidic site represented by is the same as the acid dissociation constant a1 in compound PI. Note that if compound (II) is, for example, a compound that generates an acid having two of the first acidic sites derived from the structural site X and the structural site Z, then compound PII is "two HA １ This falls under the category of "a compound having one A". When the acid dissociation constant of this compound PII is determined, compound PII is "a compound having one A １ － and one HA １ The acid dissociation constant when a compound having " and " is formed, and " １ － and one HA １ Compounds having "two A １ － The acid dissociation constant when the compound becomes "a compound having " corresponds to the acid dissociation constant a1.

[0171] The acid dissociation constant a1 is determined by the acid dissociation constant measurement method described above. Compound PII refers to the acid generated when compound (II) is irradiated with active light or radiation. The two or more structural sites X may be the same or different. Two or more of the above A １ － , and two or more of the above M １ ＋ These may be the same or different.

[0172] The nonionic site in structural site Z that can neutralize the acid is not particularly limited, and is preferably a site containing a group that can electrostatically interact with a proton, or a functional group having electrons. Examples of groups that can electrostatically interact with a proton, or functional groups having electrons, include functional groups having a macrocyclic structure such as a cyclic polyether, or functional groups having a nitrogen atom with a lone pair of electrons that does not contribute to π-conjugation. A nitrogen atom having a lone pair of electrons that does not contribute to π-conjugation is, for example, a nitrogen atom having the substructure shown in the following formula.

[0173]

[0174] Examples of substructures of functional groups having a group or electron that can electrostatically interact with a proton include crown ether structures, azacrown ether structures, primary to tertiary amine structures, pyridine structures, imidazole structures, and pyrazine structures, among which primary to tertiary amine structures are preferred.

[0175] Examples of non-cationic moieties that compound (I) and compound (II) may have include the anions described in International Publication No. 2022 / 024928, paragraphs

[0277] to

[0280] , which are incorporated herein by reference.

[0176] The content of the photoacid generator in the resist composition is not particularly limited, but is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and even more preferably 5.0% by mass or more, relative to the total solid content of the resist composition. Furthermore, the content of the photoacid generator is preferably 50.0% by mass or less, more preferably 45.0% by mass or less, and even more preferably 40.0% by mass or less, relative to the total solid content of the resist composition. Only one type of photoacid generator may be used, or two or more types may be used. When two or more types of photoacid generators are used, it is preferable that their total content is within the range of the above preferred content.

[0177] [Acid Diffusion Control Agent] The resist composition of the present invention preferably further contains an acid diffusion control agent. The acid diffusion control agent is a compound different from the above compound (N) and the above photoacid generator. The acid diffusion control agent can act as a quencher to trap excess acid generated from, for example, at least one of the compound (N) and the photoacid generator by irradiation (exposure) with active light or radiation, and to suppress the reaction of the acid-degradable resin in the unexposed area due to the excess acid.

[0178] The type of acid diffusion control agent is not particularly limited, but examples include compounds selected from basic compounds (CA), low molecular weight compounds (CB) having a nitrogen atom and a group that is eliminated by the action of an acid, and compounds (CC) whose acid diffusion control ability is reduced or lost by irradiation with active light or radiation. It is also preferable that the acid diffusion control agent is a compound that generates an acid with a pKa of 0 or more upon irradiation with active light or radiation.

[0179] (Basic compound (CA)) As the basic compound (CA), a compound having a structure represented by any of the following formulas (A) to (E) is preferred. In formulas (B), (C), (D), and (E), * represents the bond position.

[0180]

[0181] In formula (A), R ２００ ~R ２０２ Each of these independently represents a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), a cycloalkyl group (preferably having 3 to 20 carbon atoms), or an aryl group (6 to 20 carbon atoms).２００ ~R ２０２ At least two of them may be joined to form a ring. In formula (E), R ２０３ ~R ２０６ Each of these independently represents an alkyl group having 1 to 20 carbon atoms.

[0182] R in equations (A) and (E) ２００ , R ２０１ , R ２０２ , R ２０３ , R ２０４ , R ２０５ and R ２０６ The alkyl group or cycloalkyl group represented by may have substituents. Preferred substituent alkyl groups include C1-C20 aminoalkyl groups, C1-C20 hydroxyalkyl groups, or C1-C20 cyanoalkyl groups. In formulas (A) and (E), R ２００ , R ２０１ , R ２０２ , R ２０３ , R ２０４ , R ２０５ and R ２０６ The alkyl group or cycloalkyl group represented by is preferably unsubstituted.

[0183] Examples of basic compounds (CA) include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, and piperidine. The basic compound (CA) may also be a compound having at least one selected from the group consisting of an imidazole structure, a diazabicyclo structure, an onium hydroxide structure, an onium carboxylate structure, a trialkylamine structure, an aniline structure, and a pyridine structure. The basic compound (CA) may also be an alkylamine derivative having at least one selected from the group consisting of a hydroxyl group and an ether bond, or an aniline derivative having at least one selected from the group consisting of a hydroxyl group and an ether bond.

[0184] The difference between the pKa of the conjugate acid of the basic compound (CA) and the pKa of the acid generated from the compound (N) or the photoacid generator (the value obtained by subtracting the pKa of the acid generated from the compound (N) or the photoacid generator from the pKa of the conjugate acid of the basic compound (CA)) is preferably 1.00 or higher, more preferably 1.00 to 14.00, and even more preferably 2.00 to 13.00. Furthermore, the pKa of the conjugate acid of the basic compound (CA) is preferably, for example, 1.00 to 14.00, more preferably 3.00 to 13.00, and even more preferably 3.50 to 12.50.

[0185] Specific examples of basic compounds (CA) include, for example, the compounds described in paragraphs

[0132] to

[0136] of International Publication No. 2020 / 066824, which are incorporated herein by reference. Specific examples of low molecular weight compounds (CB) having a nitrogen atom and a group that is eliminated by the action of an acid include the compounds described in paragraphs

[0156] to

[0163] of International Publication No. 2020 / 066824, which are incorporated herein by reference.

[0186] (Compounds (CC) whose acid diffusion control ability is reduced or lost by irradiation with active light or radiation) Specifically, examples of compounds (CC) include onium salt compounds (CD) of acids that are relatively weak acids with respect to the above compound (N) and the above photoacid generator, and basic compounds (CE) whose basicity is reduced or lost by irradiation with active light or radiation.

[0187] Compound (CD) may be a compound that generates acid upon exposure. Preferably, compound (CD) is a compound that generates an acid with a pKa of 1.00 or more greater than the acid generated from compound (N) or the photoacid generator. The difference between the pKa of the acid generated from compound (CD) and the pKa of the acid generated from compound (N) or the photoacid generator (the value obtained by subtracting the pKa of the acid generated from compound (N) or the photoacid generator from the pKa of the acid generated from compound (CD)) is preferably 1.00 or more, more preferably 1.00 to 10.00, even more preferably 1.00 to 5.00, and particularly preferably 1.00 to 3.00. Furthermore, the pKa of the acid generated from compound (CD) is preferably, for example, 0.50 to 10.00, more preferably 0.80 to 5.00, and even more preferably 1.00 to 5.00.

[0188] The compound (CD) is preferably an onium salt compound consisting of an anion and a cation. Examples of the compound (CD) include "M ＋ X － Examples include compounds represented by " (onium salts). ＋ represents a cation, preferably an organic cation. ＋ As for M, which was described in the above explanation of the photoacid generator ＋ The same thing can be cited as X － X represents an anion, preferably an organic anion. － Examples include the anions represented by formulas (d1-1) to (d1-4) described in the above explanation of the photoacid generator.

[0189] In particular, when the above compound (CC) is an onium salt compound (CD) that is relatively weak acid with respect to the above compound (N) or the above photoacid generator, it is preferable that the onium salt (CD) is a compound containing an anion part represented by any of the following formulas (BB-1) to (BB-7).

[0190]

[0191] Specific examples of onium salt compounds (CDs) include, for example, the compounds described in paragraphs

[0305] to

[0314] of International Publication No. 2020 / 158337, which are incorporated herein by reference. Specific examples of basic compounds (CEs) include those described in paragraphs

[0137] to

[0155] and paragraph

[0164] of International Publication No. 2020 / 066824, which are incorporated herein by reference.

[0192] In addition to the compounds described above, other known compounds disclosed in paragraphs

[0627] to

[0664] of U.S. Patent Application Publication 2016 / 0070167A1, paragraphs

[0095] to

[0187] of U.S. Patent Application Publication 2015 / 0004544A1, paragraphs

[0403] to

[0423] of U.S. Patent Application Publication 2016 / 0237190A1, and paragraphs

[0259] to

[0328] of U.S. Patent Application Publication 2016 / 0274458A1 can also be suitably used as acid diffusion control agents, and such descriptions are incorporated herein by reference.

[0193] The molecular weight of the acid diffusion control agent is not particularly limited, but is preferably 100 to 3000, more preferably 150 to 2500, and even more preferably 200 to 2000.

[0194] When the resist composition of the present invention contains an acid diffusion control agent, the content of the acid diffusion control agent is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more, based on the total solid content of the resist composition. Furthermore, the content of the acid diffusion control agent is preferably 30.0% by mass or less, more preferably 20.0% by mass or less, and even more preferably 10.0% by mass or less, based on the total solid content of the resist composition. Only one type of acid diffusion control agent may be used, or two or more types may be used. When two or more types are used, it is preferable that their total content is within the range of the above preferred content.

[0195] [Resin whose polarity changes due to the action of acid] The resist composition of the present invention contains a resin whose polarity changes due to the action of acid. Examples of resins whose polarity changes due to the action of acid include resins whose polarity increases due to the action of acid (hereinafter also simply referred to as "acid-degradable resins"). It is preferable that the resist composition contains an acid-degradable resin. Acid-degradable resins will be described in detail below.

[0196] <Acid-degradable resin> (Repeating unit having an acid-degradable group) The acid-degradable resin contains a repeating unit having an acid-degradable group (hereinafter also simply referred to as "repeating unit A1"). The acid-degradable group is a group that decomposes and increases in polarity upon the action of an acid, and is typically a group that decomposes upon the action of an acid to produce a polar group. It is preferable that the acid-degradable group has a structure in which the polar group is protected by a group that is left behind upon the action of an acid (leaving group). It is preferable that the acid-degradable resin increases in polarity upon the action of an acid and decreases in solubility in organic solvents. Examples of the above polar groups include acidic groups such as carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups, sulfonic acid groups, phosphoric acid groups, sulfonamide groups, sulfonylimide groups, (alkylsulfonyl)(alkylcarbonyl)methylene groups, (alkylsulfonyl)(alkylcarbonyl)imide groups, bis(alkylcarbonyl)methylene groups, bis(alkylcarbonyl)imide groups, bis(alkylsulfonyl)methylene groups, bis(alkylsulfonyl)imide groups, tris(alkylcarbonyl)methylene groups, and tris(alkylsulfonyl)methylene groups, as well as alcoholic hydroxyl groups. Among these, carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), or sulfonic acid groups are preferred as polar groups.

[0197] Examples of groups that are eliminated by the action of an acid include the group represented by any of the following formulas: (Y1), (Y2), and (Y3). Formula (Y1): -C(Rx １ ) (Rx ２ ) (Rx ３ ) Formula (Y2): -C(R ３６ ) (Caution ３７ ) ( OR ３８) Formula (Y3): -C(Rn)(H)(Ar)

[0198] In formula (Y1), Rx １ ~Rx ３ Each of these independently represents an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an alkenyl group (linear or branched), an alkynyl group, or an aryl group (monocyclic or polycyclic). １ ~Rx ３ If all of them are alkyl groups (linear or branched), then Rx １ ~Rx ３ Preferably, at least two of them are methyl groups. Among them, Rx １ ~Rx ３ Each preferably independently represents a linear or branched alkyl group, and Rx １ ~Rx ３ It is more preferable that each of these independently represents a linear alkyl group. １ ~Rx ３ These two may combine to form a monocycle or polycycle. Rx １ ~Rx ３ Preferred alkyl groups include C1-C5 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups. １ ~Rx ３ Preferred cycloalkyl groups include monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl groups, and polycyclic cycloalkyl groups such as norbornyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups. １ ~Rx ３ A vinyl group is preferred as the alkenyl group. Rx １ ~Rx ３ The alkynyl group is preferably an ethynyl group or a propargyl group. Rx １ ~Rx ３ The preferred aryl group is one having 6 to 10 carbon atoms, such as a phenyl group, a naphthyl group, and an anthyl group.

[0199] Rx１ ~Rx ３ A cycloalkyl group is preferred as the ring formed by the bonding of these two. Rx １ ~Rx ３ The cycloalkyl group formed by the bonding of these two groups is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group, with a monocyclic cycloalkyl group having 5 to 6 carbon atoms being more preferred. １ ~Rx ３ The cycloalkyl group formed by the bonding of these two groups may have one of the methylene groups constituting the ring replaced by a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. In these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced by vinylene groups. The group represented by formula (Y1) is, for example, Rx １ is a methyl group or an ethyl group, and Rx ２ and Rx ３ A preferred embodiment is one in which the two are bonded together to form the aforementioned cycloalkyl group.

[0200] When the resist composition of the present invention is used as an EUV resist, Rx １ ~Rx ３ Alkyl groups, cycloalkyl groups, alkenyl groups, aryl groups, and Rx are represented by １ ~Rx ３ The ring formed by the bonding of these two elements may further preferably have a fluorine atom or an iodine atom as a substituent.

[0201] In formula (Y2), R ３６ ~R ３８ Each of these independently represents a hydrogen atom or a monovalent organic group. ３７ and R ３８ These may bond to each other to form a ring. Examples of monovalent organic groups include alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, alkenyl groups, and alkynyl groups. ３６It is also preferable that it be a hydrogen atom. Furthermore, the alkyl group, cycloalkyl group, aryl group, alkenyl group, and alkynyl group may include groups containing heteroatoms such as oxygen atoms and / or carbonyl groups. For example, in the alkyl group, cycloalkyl group, aryl group, and aralkyl group, one or more methylene groups may be replaced with groups containing heteroatoms such as oxygen atoms and / or carbonyl groups. ３８ R may bond with other substituents on the repeating main chain to form a ring. ３８ The group formed by the bonding of the repeating unit main chain with another substituent is preferably an alkylene group such as a methylene group. When the resist composition of the present invention is used as an EUV resist, R ３６ ~R ３８ A monovalent organic group represented by, and R ３７ and R ３８ The ring formed by the bonding of these elements may further preferably have a fluorine atom or an iodine atom as a substituent.

[0202] In formula (Y3), Ar represents an aromatic ring group. Rn represents an alkyl group, a cycloalkyl group, or an aryl group. Rn and Ar may bond to each other to form a non-aromatic ring. An aryl group is preferred as Ar. When the resist composition of the present invention is used as an EUV resist, it is also preferable that the aromatic ring group represented by Ar, and the alkyl group, cycloalkyl group, and aryl group represented by Rn, have a fluorine atom or an iodine atom as a substituent.

[0203] From the standpoint of excellent acid decomposition properties of repeating units, in a leaving group that protects a polar group, if a non-aromatic ring is directly bonded to the polar group (or its residue), it is preferable that the ring member atoms in the non-aromatic ring adjacent to the ring member atom directly bonded to the polar group (or its residue) do not have halogen atoms such as fluorine atoms as substituents.

[0204] Other groups that may be removed by the action of an acid include a 2-cyclopentenyl group having a substituent (such as an alkyl group), such as a 3-methyl-2-cyclopentenyl group, and a cyclohexyl group having a substituent (such as an alkyl group), such as a 1,1,4,4-tetramethylcyclohexyl group.

[0205] As the repeating unit A1, the repeating unit represented by formula (A) is also preferred.

[0206]

[0207] L １ R represents a divalent linking group which may have a fluorine atom or an iodine atom. １ R represents a hydrogen atom, a fluorine atom, an iodine atom, an alkyl group which may have a fluorine atom or an iodine atom, or an aryl group which may have a fluorine atom or an iodine atom. ２ This represents a leaving group that is removed by the action of an acid and may have a fluorine atom or an iodine atom. However, L １ , R １ and R ２ At least one of them has a fluorine atom or an iodine atom. １ Divalent linking groups that may have a fluorine atom or an iodine atom, represented by -CO-, -O-, -S-, -SO-, -SO ２ - Hydrocarbon groups which may have a fluorine atom or an iodine atom (for example, alkylene groups, cycloalkylene groups, alkenylene groups, and arylene groups, etc.), and linked groups formed by linking multiple thereof. Among these, L １The alkylene group is preferably -CO-, an arylene group, or an -arylene group-an alkylene group having a fluorine or iodine atom, and more preferably -CO-, or an -arylene group-an alkylene group having a fluorine or iodine atom. The arylene group is preferably a phenylene group. The alkylene group may be linear or branched. The number of carbon atoms in the alkylene group is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 3. The total number of fluorine and iodine atoms in the alkylene group having a fluorine or iodine atom is not particularly limited, but is preferably 2 or more, more preferably 2 to 10, and even more preferably 3 to 6.

[0208] R １ The alkyl group represented by may be linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but 1 to 10 is preferred, and 1 to 3 is more preferred. １ The total number of fluorine atoms and iodine atoms contained in the alkyl group having a fluorine atom or an iodine atom, represented by R, is not particularly limited, but is preferably 1 or more, more preferably 1 to 5, and even more preferably 1 to 3. １ The alkyl group represented by may contain heteroatoms other than halogen atoms, such as oxygen atoms.

[0209] R ２ Examples of leaving groups that may have a fluorine atom or an iodine atom, represented by the formulas (Y1), (Y2), and (Y3) described above, include leaving groups that have a fluorine atom or an iodine atom.

[0210] As the repeating unit A1, the repeating unit represented by formula (AI) is also preferred.

[0211]

[0212] In equation (AI), Xa １ Rx represents a hydrogen atom or an optionally substituted alkyl group. T represents a single bond or a divalent linking group. １ ~Rx ３Each of these independently represents an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an alkenyl group (linear or branched), an alkynyl group, or an aryl group (monocyclic or polycyclic). However, Rx １ ~Rx ３ If all of them are alkyl groups (linear or branched), then Rx １ ~Rx ３ It is preferable that at least two of them are methyl groups. １ ~Rx ３ These two may combine to form a monocyclic or polycyclic (such as a monocyclic or polycyclic cycloalkyl group).

[0213] Xa １ Examples of alkyl groups that may have substituents, represented by , include a methyl group or -CH ２ -R １１ The group represented by R is an example. １１ R represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group. １１ Examples of monovalent organic groups represented by include alkyl groups having 5 or fewer carbon atoms that may be substituted with halogen atoms, acyl groups having 5 or fewer carbon atoms that may be substituted with halogen atoms, and alkoxy groups having 5 or fewer carbon atoms that may be substituted with halogen atoms, with alkyl groups having 3 or fewer carbon atoms being preferred and methyl groups being more preferred. １ Preferably, the group is a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0214] Examples of divalent linking groups for T include alkylene groups, aromatic ring groups, -COO-Rt- groups, and -O-Rt- groups. In the formula, Rt represents an alkylene group or a cycloalkylene group. T is preferably a single bond or a -COO-Rt- group. When T represents a -COO-Rt- group, Rt is preferably an alkylene group having 1 to 5 carbon atoms, and -CH ２ -, - (CH ２ ) ２ - or - (CH ２ ) ３ - is preferable.

[0215] Rx １ ~Rx３ Preferred alkyl groups include C1-C4 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups. １ ~Rx ３ The preferred cycloalkyl group is a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. １ ~Rx ３ A vinyl group is preferred as the alkenyl group. Rx １ ~Rx ３ The alkynyl group is preferably an ethynyl group or a propargyl group. Rx １ ~Rx ３ The preferred aryl group is one having 6 to 10 carbon atoms, such as a phenyl group, a naphthyl group, and an anthyl group.

[0216] Rx １ ~Rx ３ The cycloalkyl group formed by the bonding of these two groups is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group. Polycyclic cycloalkyl groups such as a norbornyl group, tetracyclodecanyl group, tetracyclododecanyl group, and adamantyl group are also preferred. Among these, monocyclic cycloalkyl groups having 5 to 6 carbon atoms are preferred. Rx １ ~Rx ３ The cycloalkyl group formed by the bonding of these two may have, for example, one of the methylene groups constituting the ring replaced by a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. Furthermore, one or more of the ethylene groups constituting the cycloalkane ring of these cycloalkyl groups may be replaced by vinylene groups. In formula (AI), for example, Rx １ is a methyl group or an ethyl group, and Rx ２ and Rx ３ A preferred embodiment is one in which the two are bonded together to form the aforementioned cycloalkyl group.

[0217] When each of the above groups has substituents, examples of substituents include alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (2 to 6 carbon atoms). The number of carbon atoms of the substituent is preferably 8 or less.

[0218] The repeating unit represented by formula (AI) is an acid-degradable (meth)acrylic acid tertiary alkyl ester repeating unit (Xa １ A repeating unit in which represents a hydrogen atom or a methyl group, and T represents a single bond, is preferred.

[0219] The repeating unit A1 may have an acid-degradable group containing an unsaturated bond. The repeating unit represented by formula (B) is preferred as the repeating unit having an acid-degradable group containing an unsaturated bond.

[0220]

[0221] In formula (B), Xb represents a hydrogen atom, a halogen atom, or an optionally substituted alkyl group. L represents a single bond or an optionally substituted divalent linking group. １ ~Ry ３ Each of these independently represents a linear or branched alkyl group, a monocyclic or polycyclic cycloalkyl group, an alkenyl group, an alkynyl group, or a monocyclic or polycyclic aryl group. However, Ry １ ~Ry ３ At least one of these represents an alkenyl group, an alkynyl group, a monocyclic or polycyclic cycloalkenyl group, or a monocyclic or polycyclic aryl group. １ ~Ry ３ These two may combine to form a monocyclic or polycyclic (monocyclic or polycyclic cycloalkyl group, cycloalkenyl group, etc.) structure.

[0222] Examples of alkyl groups that may have substituents, represented by Xb, include a methyl group or -CH ２ -R １１ The group represented by R is an example. １１Xb represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group. Examples include alkyl groups having 5 or fewer carbon atoms that may be substituted with a halogen atom, acyl groups having 5 or fewer carbon atoms that may be substituted with a halogen atom, and alkoxy groups having 5 or fewer carbon atoms that may be substituted with a halogen atom. Alkyl groups having 3 or fewer carbon atoms are preferred, and methyl groups are more preferred. Xb is preferably a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0223] Examples of divalent linking groups represented by L include -Rt-, -CO-, -COO-Rt-, -COO-Rt-CO-, -Rt-CO-, and -O-Rt-. Rt represents an alkylene group, a cycloalkylene group, or an aromatic ring group, with an aromatic ring group being preferred. Rt may have substituents such as a halogen atom, a hydroxyl group, or an alkoxy group. As for L, -Rt-, -CO-, -COO-Rt-CO-, or -Rt-CO- are preferred.

[0224] Ry １ ~Ry ３ The alkyl group represented is preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, or t-butyl group. １ ~Ry ３ The cycloalkyl group represented by is preferably a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. １ ~Ry ３ A vinyl group is preferred as the alkenyl group represented by Ry. １ ~Ry ３ As the alkynyl group represented by , an ethynyl group is preferred. １ ~Ry ３ The cycloalkenyl group represented by is preferably a cyclopentyl group and a monocyclic cycloalkyl group such as a cyclohexyl group that contains a double bond in part. １ ~Ry３ The aryl group represented by is preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group, a naphthyl group, and an anthyl group.

[0225] Ry １ ~Ry ３ The cycloalkyl group formed by the bonding of these two groups is preferably a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. Among these, a monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferred. １ ~Ry ３ A cycloalkyl group or cycloalkenyl group formed by the bonding of these two elements may, for example, have one of the methylene groups constituting the ring be a heteroatom such as an oxygen atom, a carbonyl group, or -SO ２ -Base and -SO ３ - These groups may be replaced by groups containing heteroatoms such as - groups, vinylidene groups, or combinations thereof. Furthermore, in these cycloalkyl or cycloalkenyl groups, one or more ethylene groups constituting the cycloalkane or cycloalkene ring may be replaced by vinylene groups. The repeating unit represented by formula (B) is, for example, Ry １ is a methyl group, ethyl group, vinyl group, allyl group, or aryl group, R ２ and Ry ３ A preferred embodiment is one in which the two are bonded together to form the aforementioned cycloalkyl group or cycloalkenyl group.

[0226] When each of the above groups has substituents, examples of substituents include alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (2 to 6 carbon atoms). The number of carbon atoms of the substituent is preferably 8 or less.

[0227] The repeating units represented by formula (B) are preferably acid-degradable (meth)acrylic acid tertiary ester repeating units (a repeating unit in which Xb represents a hydrogen atom or a methyl group and L represents a -CO- group), acid-degradable hydroxystyrene tertiary alkyl ether repeating units (a repeating unit in which Xb represents a hydrogen atom or a methyl group and L represents a phenyl group), or acid-degradable styrene carboxylic acid tertiary ester repeating units (a repeating unit in which Xb represents a hydrogen atom or a methyl group and L represents a -Rt-CO- group (Rt is an aromatic group)).

[0228] Specific examples of repeating units having an acid-degradable group containing an unsaturated bond include, for example, the repeating units described in

[0067] to

[0071] of International Publication No. 2022 / 024928, which are incorporated herein by reference.

[0229] Specific examples of repeating unit A1 (a repeating unit having an acid-degradable group) are shown below, but are not limited to these. Repeating units having an acid-degradable group described in the examples later are also preferred. Furthermore, for specific examples of repeating unit A1, one can refer to, for example, the descriptions in

[0029] to

[0071] of International Publication No. 2022 / 024928, which are incorporated herein by reference.

[0230]

[0231] The content of repeating unit A1 is preferably 15 mol% or more, more preferably 40 mol% or more, and even more preferably 60 mol% or more, relative to the total repeating units in the acid-degradable resin. Furthermore, the content of repeating unit A1 is preferably less than 100 mol%, more preferably 95 mol% or less, and even more preferably 90 mol% or less, relative to the total repeating units in the acid-degradable resin. The acid-degradable resin may contain one type of repeating unit A1 or two or more types. If the acid-degradable resin contains two or more types of repeating unit A1, it is preferable that their total content is within the range of the above preferred content.

[0232] (Repeating units having acidic groups) Acid-degradable resins preferably contain repeating units having acidic groups (hereinafter also simply referred to as "repeating unit A2"). Repeating unit A2 is preferably a different repeating unit from the above repeating unit A1 (repeating unit having an acid-degradable group). Repeating unit A2 may also have a fluorine atom or an iodine atom. Preferred acidic groups are carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), sulfonic acid groups, sulfonamide groups, or isopropanol groups. Among these, repeating unit A2 is preferably a repeating unit having a phenolic hydroxyl group. The above hexafluoroisopropanol group may have one or more fluorine atoms (preferably 1 to 2) substituted with a group other than a fluorine atom (such as an alkoxycarbonyl group). As for the acidic group, the -C(CF) formed in this way ３ ) (OH)-CF ２ - is also preferable. In addition, one or more fluorine atoms are substituted with a group other than a fluorine atom, -C(CF ３ ) (OH)-CF ２ A ring containing - may be formed.

[0233] The repeating unit A2 is preferably a repeating unit represented by the following formula (Pa1), and the acid-degradable resin preferably contains the repeating unit represented by the following formula (Pa1).

[0234]

[0235] In formula (Pa1), R ａ１ and R ａ２ Each of these independently represents a hydrogen atom or a substituent. ａ１ Ar represents a single bond or a divalent linking group. ａ１ Ar represents an aromatic ring group with (m+n+1) valency. ａ１ And, R ａ２ or L ａ１ This may be a single bond or a bond via a linking group. Ｘ represents a substituent other than a hydroxyl group. n represents an integer between 1 and 9 (inclusive). m represents an integer between 0 and 8 (inclusive).

[0236] In the above formula (Pa1), R ａ１ and R ａ２ Each of these independently represents a hydrogen atom or a substituent. ａ１ and R ａ２ The substituent represented is not particularly limited, but is preferably an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. ａ１ and R ａ２ The alkyl group represented by may be linear or branched, and may have substituents. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 3. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups. ａ１ and R ａ２ The number of carbon atoms in the cycloalkyl group represented by is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. The cycloalkyl group may be a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. The cycloalkyl group may have substituents. ａ１ and R ａ２ Examples of halogen atoms represented by include fluorine, chlorine, bromine, and iodine atoms, with fluorine or iodine atoms being preferred. ａ１ and R ａ２ The alkyl group contained in the alkoxycarbonyl group represented by may be linear or branched. The number of carbon atoms in the alkyl group contained in the alkoxycarbonyl group is not particularly limited, but 1 to 5 is preferred, and 1 to 3 is more preferred. The alkoxycarbonyl group may have substituents.

[0237] In the above formula (Pa1), L ａ１ L represents a single bond or a divalent linking group. ａ１ Examples of divalent linking groups represented by include -COO- and -CONR ａ３ -, alkylene groups, or groups formed by combining two or more of these groups.ａ３ R represents a hydrogen atom or an alkyl group. Preferred alkylene groups include C1-C8 alkylene groups such as methylene, ethylene, propylene, butylene, hexylene, and octylene. The alkylene group may have substituents. ａ３ Examples of alkyl groups that represent an alkyl group include alkyl groups having 20 or fewer carbon atoms, such as methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, hexyl group, 2-ethylhexyl group, octyl group, and dodecyl group, with alkyl groups having 8 or fewer carbon atoms being preferred.

[0238] In the above formula (Pa1), Ar ａ１ Ar represents an aromatic ring group with (m+n+1) valency. ａ１ The aromatic ring group represented by may be either an aromatic hydrocarbon group or an aromatic heterocyclic group. Preferred aromatic hydrocarbon groups include groups containing aromatic hydrocarbons having 6 to 18 carbon atoms, such as benzene, naphthalene, anthracene, and naphthacene. Preferred aromatic heterocyclic groups include groups containing aromatic heterocyclic rings with 4 to 20 ring member atoms, such as thiophene, furan, pyridine, pyrrole, benzothiophene, benzofuran, benzopyrrole, triazine, imidazole, benzimidazole, triazole, thiadiazole, and thiazole.

[0239] Ar ａ１ And, R ａ２ or L ａ１ These may be bonded via single bonds or linking groups. Examples of linking groups include -O-, -S-, -CO-, and -CO ２ -, -SO-, -SO ２ - Examples include alkylene groups (preferably having 1 to 5 carbon atoms), alkenylene groups (preferably having 2 to 5 carbon atoms), and groups formed by combining two or more of these. The alkylene groups and alkenylene groups may have substituents.

[0240] In the above formula (Pa1), R Ｘ R represents substituents other than hydroxyl groups. ＸExamples of substituents represented by include carboxyl groups, sulfo groups, cyano groups, halogen atoms, hydrocarbon groups, amino groups, nitro groups, and groups formed by combining two or more of these. Ｘ Examples of hydrocarbon groups represented by include alkyl groups (preferably having 1 to 10 carbon atoms), cycloalkyl groups (preferably having 5 to 15 carbon atoms), and alkenyl groups (preferably having 2 to 10 carbon atoms). Ｘ The hydrocarbon group represented by may have substituents. Also, R Ｘ The hydrocarbon group represented is -CH ２ If it contains -, -CH ２ At least one of the following is -O-, -CO-, -S-, and -SO ２ - May be replaced by at least one selected from the group consisting of -. Ｘ The substituent represented by preferably has a halogen atom. The halogen atom is preferably a fluorine atom or an iodine atom.

[0241] In the above formula (Pa1), n ​​represents an integer between 1 and 9, preferably between 1 and 5, and more preferably between 1 and 4. m represents an integer between 0 and 8, preferably between 0 and 4, and more preferably between 0 and 3.

[0242] The repeating unit A2 is preferably a repeating unit represented by the following formula (Pa2), and the acid-degradable resin preferably contains the repeating unit represented by the following formula (Pa2).

[0243]

[0244] In formula (Pa2), R ａ４ L represents a hydrogen atom or an alkyl group. ａ２ represents a single join or -COO-. r represents an integer between 0 and 3 (inclusive). Ｘ１ represents a halogen atom or hydrocarbon group. n1 represents an integer between 1 and 5. m1 represents an integer between 0 and 4.

[0245] In the above formula (Pa2), R ａ４ R represents a hydrogen atom or an alkyl group.ａ４ The alkyl group represented by may be linear or branched and may have substituents. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 5, and particularly preferably 1 to 3. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups.

[0246] In the above formula (Pa2), L ａ２ represents a single bond or -COO-, with a single bond being preferred. r represents an integer between 0 and 3, preferably between 0 and 2, more preferably 0 or 1, and even more preferably 0. In formula (Pa2), the aromatic ring becomes benzene when r is 0, naphthalene when r is 1, anthracene when r is 2, and naphthacene when r is 3. n1 represents an integer between 1 and 5, preferably between 1 and 4. m1 represents an integer between 0 and 4, preferably between 0 and 3.

[0247] In the above formula (Pa2), R Ｘ１ R represents a halogen atom or hydrocarbon group. Ｘ１ The halogen atom represented is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, and more preferably a fluorine atom or an iodine atom. Ｘ１ Examples of hydrocarbon groups represented by include alkyl groups (preferably having 1 to 10 carbon atoms), cycloalkyl groups (preferably having 5 to 15 carbon atoms), and alkenyl groups (preferably having 2 to 10 carbon atoms). Ｘ１ The hydrocarbon group represented by may have substituents. Also, R Ｘ１ The hydrocarbon group represented by -CH ２ If it contains -, -CH ２ At least one of the following is -O-, -CO-, -S-, and -SO ２ - May be replaced by at least one selected from the group consisting of -. Ｘ１ The hydrocarbon group represented by preferably has a halogen atom. The halogen atom is preferably a fluorine atom or an iodine atom.

[0248] Specific examples of repeating unit A2 (a repeating unit having an acid group) are shown below, but are not limited to these. In the following structural formula, G １ and G ２ Each of these independently represents a hydrogen atom, a methyl group, a fluorine atom, a chlorine atom, a trifluoromethyl group, a cyano group, a hydroxyl group, or a hydroxymethyl group. f1 represents an integer from 1 to 3. Repeating unit A2 described in the examples below is also preferred. Specific examples of repeating unit A2 include, for example, the repeating unit described in

[0079] to

[0110] of International Publication No. 2022 / 024928, which is incorporated herein by reference.

[0249] When the acid-degradable resin contains repeating units A2, the content of repeating units A2 is preferably 10 mol% or more, and more preferably 15 mol% or more, relative to the total repeating units in the acid-degradable resin. Furthermore, the content of repeating units A2 is preferably less than 60 mol%, and more preferably 50 mol% or less, relative to the total repeating units in the acid-degradable resin.

[0250] (Repeating units that do not have either an acid-degradable group or an acid group, but have a fluorine atom, a bromine atom, or an iodine atom) In addition to the repeating units A1 and A2 described above, the acid-degradable resin may also have repeating units that do not have either an acid-degradable group or an acid group, but have a fluorine atom, a bromine atom, or an iodine atom (hereinafter also simply referred to as "repeating unit X"). It is preferable that repeating unit X is different from repeating units Y and P described later. The repeating unit X is preferably the repeating unit represented by formula (C).

[0251]

[0252] In formula (C), L ５ R represents a single bond or an ester group. ９ R represents an alkyl group which may have a hydrogen atom, or a fluorine atom or an iodine atom. １０This represents an alkyl group which may have a hydrogen atom, a fluorine atom, or an iodine atom, a cycloalkyl group which may have a fluorine atom or an iodine atom, an aryl group which may have a fluorine atom or an iodine atom, or a group which is a combination thereof.

[0253] The content of repeating units X is preferably 0 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, relative to the total repeating units in the acid-degradable resin. Furthermore, the upper limit is preferably less than 40 mol%, and more preferably 35 mol% or less, relative to the total repeating units in the acid-degradable resin.

[0254] Furthermore, the acid-degradable resin may have repeating units having at least one of a fluorine atom, a bromine atom, and an iodine atom. Examples of repeating units having at least one of a fluorine atom, a bromine atom, and an iodine atom include repeating units having a fluorine atom, a bromine atom, or an iodine atom and having an acid-degradable group, repeating units having a fluorine atom, a bromine atom, or an iodine atom and having an acid group, and repeating units having a fluorine atom, a bromine atom, or an iodine atom. The total content of repeating units having at least one of a fluorine atom, a bromine atom, and an iodine atom among the repeating units of the acid-degradable resin is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, and particularly preferably 40 mol% or more, relative to the total repeating units of the acid-degradable resin. There is no particular upper limit, but for example, it is 100 mol% or less relative to the total repeating units of the acid-degradable resin.

[0255] Specific examples of repeating units having fluorine atoms or iodine atoms include, for example, the repeating units described in

[0116] to

[0117] of International Publication No. 2022 / 024928, which are incorporated herein by reference.

[0256] (Repeating units having lactone groups, sultone groups, or carbonate groups) Acid-degradable resins may have repeating units (hereinafter also simply referred to as "repeating unit Y") having at least one selected from the group consisting of lactone groups, sultone groups, and carbonate groups. It is also preferable that repeating unit Y does not have acidic groups such as hydroxyl groups and hexafluoropropanol groups.

[0257] The lactone group or sultone group may have a lactone structure or a sultone structure. The lactone structure or sultone structure is preferably a 5-7 membered ring lactone structure or a 5-7 membered ring sultone structure. More preferably, the 5-7 membered ring lactone structure is fused with another ring structure in the form of a bicyclo or spiro structure, or the 5-7 membered ring sultone structure is fused with another ring structure in the form of a bicyclo or spiro structure. For units containing a lactone group or sultone group, refer to, for example, the descriptions in International Publication No. 2022 / 024928

[0119] to

[0126] and

[0132] to

[0133] , which are incorporated herein by reference.

[0258] A cyclic carbonate ester group is preferred as the carbonate group. For repeating units having a cyclic carbonate ester group, see, for example, the descriptions in

[0127] to

[0133] of International Publication No. 2022 / 024928, which are incorporated herein by reference.

[0259] When the acid-degradable resin contains repeating units Y, the content of repeating units Y is preferably 1 mol% or more, and more preferably 10 mol% or more, relative to the total repeating units in the acid-degradable resin. Furthermore, the upper limit is preferably less than 40 mol%, and more preferably 35 mol% or less, relative to the total repeating units in the acid-degradable resin.

[0260] (Repeating units having photoacid generating groups) Acid-degradable resins may contain repeating units having groups that generate acid upon irradiation with active light or radiation (also called "photoacid generating groups"), but it is also preferable that acid-degradable resins do not contain repeating units having photoacid generating groups (hereinafter also simply called "repeating unit P"). An example of repeating unit P is the repeating unit represented by formula (4).

[0261]

[0262] R ４１ L represents a hydrogen atom or a methyl group. ４１ L represents a single bond or a divalent linking group. ４２ R represents a divalent linking group. ４０ This represents a structural site that decomposes upon irradiation with active light or radiation, generating acid in the side chain.

[0263] L ４１ L represents a single bond or a divalent linking group, preferably a single bond or an ester bond (-COO-). ４２ These are alkylene groups, cycloalkylene groups, arylene groups, -O-, -CO-, -S-, -SO-, -SO ２ It is preferable that the linking group consists of at least one selected from the group consisting of - and -NR-. R represents a hydrogen atom or an organic group (preferably an organic group having 1 to 10 carbon atoms, such as an alkyl group, cycloalkyl group, or aryl group). The alkylene group may be linear or branched. The number of carbon atoms in the alkylene group is not particularly limited, but 1 to 10 is preferred. The cycloalkylene group may be a monocyclic or polycyclic cycloalkylene group. The number of carbon atoms in the cycloalkylene group is not particularly limited, but 3 to 20 is preferred, and 5 to 15 is more preferred. The number of carbon atoms in the arylene group is not particularly limited, but 6 to 20 is preferred, and 6 to 10 is more preferred. The alkylene group, cycloalkylene group and arylene group may have substituents, and the substituent T mentioned above is an example of a substituent.

[0264] R ４０ Preferably, the group is represented by the following formula (S4-1).

[0265]

[0266] In equation (S4-1), Q － represents an acid residue, M ＋ * represents a cation. * represents L ４１ This indicates the bonding position. An acid residue is a group formed when a proton dissociates from an acid. Q － is a carboxylate anion group (COO － ), sulfonate anion group (SO ３ － ), or sulfonamide group (N － -SO ２ R Ｎ１ It is represented by R Ｎ１ represents an organic group, and examples include organic groups having 1 to 10 carbon atoms, with alkyl groups, fluoroalkyl groups, or aryl groups being preferred. A sulfonate anion group is more preferred. ＋ For further explanation, specific examples, and preferred ranges, please refer to the M section in the above description of the photoacid generator. ＋ It is the same as this.

[0267] Specific examples of repeating units P include, for example, the repeating units described in paragraphs

[0094] to

[0105] of Japanese Patent Publication No. 2014-041327, the repeating units described in paragraph

[0094] of International Publication No. 2018 / 193954, and the repeating units described in paragraph

[0138] of International Publication No. 2022 / 024928, and these descriptions are incorporated herein by reference. Furthermore, examples of repeating units represented by formula (4) include, for example, the repeating units described in paragraphs

[0094] to

[0105] of Japanese Patent Publication No. 2014-041327, and the repeating units described in paragraph

[0094] of International Publication No. 2018 / 193954, and these descriptions are incorporated herein by reference.

[0268] When the acid-degradable resin contains repeating units P, the content of repeating units P is preferably 1 mol% or more, more preferably 3 mol% or more, and even more preferably 5 mol% or more, relative to the total repeating units in the acid-degradable resin. Furthermore, the content of repeating units P is preferably less than 40 mol%, more preferably 30 mol% or less, and even more preferably 20 mol% or less, relative to the total repeating units in the acid-degradable resin.

[0269] (Repeating units represented by formula (V-1) or formula (V-2)) Acid-degradable resins may have repeating units represented by the following formula (V-1) or formula (V-2). It is preferable that the repeating units represented by formula (V-1) and the following formula (V-2) are different from the repeating units described above.

[0270]

[0271] In equation (V-1) and equation (V-2) below, R ６ and R ７ Each of these independently represents a hydrogen atom, a hydroxyl group, an alkyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR or -COOR: R is an alkyl group having 1 to 6 carbon atoms or a fluorinated alkyl group), or a carboxyl group. As the alkyl group, a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms is preferred. ３ n represents an integer between 0 and 6. ４ X represents an integer between 0 and 4. ４ represents a methylene group, an oxygen atom, or a sulfur atom. Examples of repeating units represented by formula (V-1) or (V-2) include the repeating units described in paragraph

[0100] of International Publication No. 2018 / 193954, which are incorporated herein by reference.

[0272] (Repeating units to reduce the mobility of the main chain) Acid-degradable resins are preferable to have a high glass transition temperature (Tg) in order to suppress excessive diffusion of generated acid or pattern breakdown during development. For repeating units to reduce the mobility of the main chain, refer to the contents of

[0144] to

[0160] of International Publication No. 2022 / 024928.

[0273] (Repeating units having at least one group selected from lactone groups, sultone groups, carbonate groups, hydroxyl groups, cyano groups, and alkali-soluble groups) Acid-degradable resins may have repeating units having at least one group selected from lactone groups, sultone groups, carbonate groups, hydroxyl groups, cyano groups, and alkali-soluble groups. Examples of repeating units having lactone groups, sultone groups, or carbonate groups in acid-degradable resins include the repeating units described above for repeating unit Y. Preferred content is also as described for repeating unit Y.

[0274] The acid-degradable resin may have repeating units having a hydroxyl group or a cyano group. This improves substrate adhesion. The repeating units having a hydroxyl group or a cyano group are preferably repeating units having a saturated hydrocarbon group having a hydroxyl group or a cyano group (substituted with a hydroxyl group or a cyano group). Alternatively, they may be repeating units having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group. The repeating units having a hydroxyl group or a cyano group are preferably not having an acid-degradable group. Examples of repeating units having a hydroxyl group or a cyano group include the repeating units described in paragraphs

[0081] to

[0084] of Japanese Patent Application Publication No. 2014-098921, and the above description is incorporated herein by reference.

[0275] The acid-degradable resin may have repeating units having alkali-soluble groups. The inclusion of repeating units having alkali-soluble groups in the acid-degradable resin increases the resolution in contact hole applications. Examples of alkali-soluble groups include carboxyl groups, sulfonamide groups, sulfonylimide groups, bissulfonylimide groups, and aliphatic alcohol groups (e.g., hexafluoroisopropanol group) whose α-position is substituted with an electron-withdrawing group, with carboxyl groups being preferred. Examples of repeating units having alkali-soluble groups include the repeating units described in paragraphs

[0085] and

[0086] of Japanese Patent Application Publication No. 2014-098921, the above description is incorporated herein by reference.

[0276] (Repeating units having an alicyclic hydrocarbon structure and not exhibiting acid decomposition) Acid-degradable resins may have repeating units having an alicyclic hydrocarbon structure and not exhibiting acid decomposition. This reduces the elution of low-molecular-weight components from the resist film into the immersion liquid during immersion exposure. Examples of repeating units having an alicyclic hydrocarbon structure and not exhibiting acid decomposition include repeating units derived from 1-adamantyl (meth)acrylate, diamantyl (meth)acrylate, tricyclodecanyl (meth)acrylate, or cyclohexyl (meth)acrylate.

[0277] (Repeating units represented by formula (III) that do not have either a hydroxyl group or a cyano group) Acid-degradable resins may have repeating units represented by formula (III) that do not have either a hydroxyl group or a cyano group.

[0278]

[0279] In formula (III), R ５ represents a hydrocarbon group having at least one cyclic structure and lacking both a hydroxyl group and a cyano group. Ra represents a hydrogen atom, an alkyl group, or -CH ２ -O-Ra ２ It represents the base. In the formula, Ra ２represents a hydrogen atom, an alkyl group, or an acyl group. Examples of repeating units represented by formula (III) that do not have either a hydroxyl group or a cyano group include the repeating units described in paragraphs

[0087] to

[0094] of Japanese Patent Application Publication No. 2014-098921, which are incorporated herein by reference.

[0280] (Other Repeating Units) Furthermore, the acid-degradable resin may have other repeating units besides those described above. For example, refer to the descriptions in

[0141] to

[0143] and

[0169] to

[0170] of International Publication No. 2022 / 024928, which are incorporated herein by reference.

[0281] In addition to the repeating structural units described above, acid-degradable resins may have various repeating structural units for the purpose of adjusting dry etching resistance, suitability for standard developers, substrate adhesion, resist profile, resolution, heat resistance, and sensitivity.

[0282] A preferred embodiment of the present invention is that the acid-degradable resin has at least one selected from the group consisting of lactone groups, carbonate groups, sultone groups, and saturated hydrocarbon groups having hydroxyl groups. Having at least one selected from the group consisting of lactone groups, carbonate groups, sultone groups, and saturated hydrocarbon groups having hydroxyl groups further improves etching resistance and LWR performance.

[0283] In a preferred embodiment of the present invention, the acid-degradable resin contains repeating units having iodine atoms. By including repeating units having iodine atoms in the acid-degradable resin, the absorption rate of EUV light and the like is increased, the effects of shot noise can be reduced, and the LWR performance is further improved.

[0284] In one preferred embodiment of the present invention, the acid-degradable resin contains repeating units having an aromatic ring. The repeating units containing the aromatic ring may be any of the repeating units described above. Furthermore, it is preferable that the acid-degradable resin contains repeating units having a hydroxyl group bonded to the aromatic ring. In particular, it is preferable that the repeating unit A2 contains a repeating unit having a hydroxyl group bonded to the aromatic ring.

[0285] Acid-degradable resins can be synthesized according to conventional methods (e.g., radical polymerization). According to the GPC method, the weight-average molecular weight (Mw) of the acid-degradable resin, expressed as polystyrene equivalent, is preferably 30,000 or less, more preferably 1,000 to 30,000, even more preferably 3,000 to 30,000, and particularly preferably 5,000 to 15,000. The degree of dispersion (molecular weight distribution, Mw / Mn) of the acid-degradable resin is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, even more preferably 1.1 to 2.0, and particularly preferably 1.1 to 1.5. Lower dispersion results in better resolution and resist shape, smoother sidewalls of the resist pattern, and superior roughness.

[0286] The content of the acid-degradable resin in the resist composition is preferably 30.0 to 99.9% by mass, more preferably 40.0 to 99.9% by mass, and even more preferably 60.0 to 90.0% by mass, based on the total solid content of the resist composition. The acid-degradable resin may be used alone or in combination of two or more types. When two or more types are used, it is preferable that their total content is within the above preferred content range.

[0287] [Hydrophobic Resin] The resist composition of the present invention may contain a hydrophobic resin different from the acid-degradable resin. The hydrophobic resin is preferably designed to be unevenly distributed on the surface of the resist film, but unlike surfactants, it does not necessarily need to have hydrophilic groups in its molecule and does not need to contribute to the uniform mixing of polar and nonpolar substances.

[0288] Hydrophobic resins, in terms of their uneven distribution on the film surface, contain fluorine atoms, silicon atoms, and CH4 atoms in the side chain portion of the resin. ３ It is preferable that the substructure has one or more of these substructures, and more preferably two or more. Furthermore, the hydrophobic resin preferably has a hydrocarbon group having 5 or more carbon atoms. These groups may be present in the main chain of the resin or substituted in the side chain. Examples of hydrophobic resins include the compounds described in paragraphs

[0275] to

[0279] of International Publication No. 2020 / 004306, which are incorporated herein by reference.

[0289] When the resist composition contains a hydrophobic resin, the content of the hydrophobic resin is preferably 0.01 to 20.0% by mass, more preferably 0.1 to 10.0% by mass, and even more preferably 0.1 to 5.0% by mass, based on the total solid content of the resist composition. Only one type of hydrophobic resin may be used, or two or more types may be used. When two or more types are used, it is preferable that their total content is within the above preferred content range.

[0290] [Surfactants] The resist composition of the present invention may contain surfactants. The inclusion of surfactants allows for better adhesion and the formation of patterns with fewer development defects. Fluorine-based and / or silicone-based surfactants are preferred. Examples of fluorine-based and / or silicone-based surfactants include those disclosed in paragraphs

[0218] and

[0219] of International Publication No. 2018 / 193954.

[0291] If the resist composition contains a surfactant, the surfactant content is preferably 0.0001 to 2.0% by mass, more preferably 0.0005 to 1.0% by mass, and even more preferably 0.1 to 1.0% by mass, relative to the total solid content of the resist composition. One type of surfactant may be used, or two or more types may be used. If two or more types are used, it is preferable that their total content is within the range of the above preferred content.

[0292] [Solvent] The resist composition of the present invention contains a solvent. Preferably, the solvent contains (M1) propylene glycol monoalkyl ether carboxylate and (M2) at least one selected from the group consisting of propylene glycol monoalkyl ether, lactic acid ester, acetate ester, alkoxypropionic acid ester, linear ketone, cyclic ketone, lactone, and alkylene carbonate. The solvent may further contain components other than components (M1) and (M2). Details of components (M1) and (M2) are described in paragraphs

[0218] to

[0226] of International Publication No. 2020 / 004306, and these contents are incorporated herein by reference. The solvent content in the resist composition is preferably set so that the solid content concentration is 0.5 to 30% by mass, and more preferably 1 to 20% by mass. If the solvent further contains components other than components (M1) and (M2), the content of the components other than components (M1) and (M2) is preferably 5 to 30% by mass relative to the total amount of the solvent.

[0293] [Other Additives] The resist composition of the present invention may further contain, as other additives, at least one selected from the group consisting of dissolution-inhibiting compounds, dyes, plasticizers, photosensitizers, light absorbers, and compounds that promote solubility in developer solutions (for example, phenol compounds with a molecular weight of 1000 or less, or alicyclic or aliphatic compounds containing a carboxyl group). The above-mentioned "dissolution-inhibiting compounds" are compounds with a molecular weight of 3000 or less that decompose due to the action of acid, thereby reducing their solubility in organic developer solutions.

[0294] The content of other additives is not particularly limited, but may be 20.0% by mass or less, 10.0% by mass or less, or 5.0% by mass or less, relative to the total solid content of the resist composition. Only one type of other additive may be used, or two or more types may be used. When two or more types are used, it is preferable that their total content is within the range of the above preferred content.

[0295] Furthermore, the resist composition of the present invention may contain water as an impurity. When water is present as an impurity, a smaller amount of water is preferable, but it may be present in an amount of 1 to 30,000 ppm by mass relative to the total resist composition. Furthermore, the resist composition may contain residual monomers as impurities (for example, monomers derived from raw material monomers used in the synthesis of the resin). When residual monomers are present as impurities, a smaller amount of residual monomers is preferable, but it may be present in an amount of 1 to 30,000 ppm by mass relative to the total solid content of the resist composition.

[0296] [Resist Film, Pattern Forming Method] The present invention also relates to a resist film formed using the photosensitive or radiation-sensitive resin composition (resist composition) of the present invention. The pattern forming method of the present invention is a pattern forming method comprising the steps of: (1) forming a resist film on a substrate using the photosensitive or radiation-sensitive resin composition (resist composition) of the present invention; (2) exposing the resist film; and (3) developing the exposed resist film using a developer. Each of the above steps will be described in detail below.

[0297] [Step (1)] Step (1) is a step of forming a resist film on a substrate using the resist composition of the present invention. Details of the resist composition of the present invention used in step (1) are as described above.

[0298] One method for forming a resist film on a substrate using a resist composition is to coat the resist composition onto the substrate. If necessary, it is preferable to filter the resist composition before coating. The pore size of the filter is preferably 0.1 μm or less, more preferably 0.03 μm or less, even more preferably 0.01 μm or less, and particularly preferably 0.005 μm or less. The lower limit of the filter pore size is not particularly limited, but may be 0.001 μm or more. The material of the filter is not particularly limited, but if it is a polymer, it is preferably made of polyolefins such as polyethylene (PE) and polypropylene (PP) (including high density and ultra-high molecular weight); polyamides such as nylon 6 and nylon 66; polyimide (PI); polyamideimide; polyesters such as polyethylene terephthalate; polyethersulfone; cellulose; polyfluorocarbons such as polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkanes; derivatives of the above polymers; and more preferably at least one selected from the group consisting of polyolefins, polyamides, polyimides, polyamideimide, polyesters, polysulfones, cellulose, polyfluorocarbons and their derivatives. In addition to resins, diatomaceous earth, glass, etc. may also be used.

[0299] The resist composition may be filtered using one filter or a combination of two or more filters. If two or more filters are used, they may be the same filter or different filters. The resist composition may also be circulated and filtered repeatedly using the same filter.

[0300] The resist composition can be applied to a substrate (e.g., silicon, silicon coated with silicon dioxide, etc.) used in the manufacture of integrated circuit elements by a suitable coating method such as a spinner or coater. Spin coating using a spinner is preferred. The preferred rotation speed when spin coating using a spinner is 1000 to 3000 rpm (rotations per minute). After applying the resist composition, the substrate may be dried to form a resist film. If necessary, various undercoats (inorganic films, organic films, anti-reflective films, etc.) may be formed in the layer below the resist film.

[0301] As for drying methods, one example is drying by heating. Heating can be carried out using means provided in at least one of a normal exposure machine and a developer machine, and may also be carried out using a hot plate or the like. The heating temperature is not particularly limited, but is preferably 80 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 130°C. The heating time is not particularly limited, but is preferably 30 to 1000 seconds, more preferably 60 to 800 seconds, and even more preferably 60 to 600 seconds.

[0302] The present invention also includes a resist film obtained in step (1). The thickness of the resist film is not particularly limited, but 10 to 120 nm is preferred in that it is possible to form finer patterns with higher precision. In particular, when EUV exposure is used, the thickness of the resist film is more preferably 10 to 65 nm, and even more preferably 15 to 50 nm. When ArF immersion exposure is used, the thickness of the resist film is more preferably 10 to 120 nm, and even more preferably 15 to 90 nm.

[0303] A topcoat may be formed on the upper layer of the resist film using a topcoat composition. For example, it is preferable to form a topcoat containing a basic compound, such as that described in Japanese Patent Application Publication No. 2013-61648, on the resist film. Specific examples of basic compounds that the topcoat may contain include basic compounds that may be contained in the resist composition.

[0304] [Step (2)] Step (2) is a step of exposing the resist film formed in step (1). Methods of exposure include irradiating the formed resist film with active light or radiation through a predetermined mask. Examples of active light or radiation include infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-rays, and electron beams, preferably with a wavelength of 250 nm or less, more preferably 220 nm or less, and particularly preferably far ultraviolet light with a wavelength of 1 to 200 nm, specifically KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ２ Examples include excimer lasers (157 nm), EUV (13.5 nm), X-rays, and electron beams.

[0305] It is preferable to bake (heat) the image after exposure but before developing. This step is also called post-exposure baking. Baking promotes the reaction of the exposed area, resulting in better sensitivity and pattern shape. The baking temperature is not particularly limited, but is preferably 80 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 130°C. The baking time is not particularly limited, but is preferably 10 to 1000 seconds, more preferably 10 to 180 seconds, and even more preferably 30 to 120 seconds. Heating can be carried out using means provided in at least one of a normal exposure machine and a developer, and may also be done using a hot plate or the like.

[0306] [Step (3)] Step (3) is a step in which the resist film exposed in step (2) is developed using a developer. By performing step (3), a resist pattern (also simply called a "pattern") is formed. The developer used in step (3) may be an alkaline developer or a developer containing an organic solvent (hereinafter also called an organic developer). Examples of development methods include immersing the substrate in a tank filled with developer for a certain period of time (dip method), puddling the developer on the substrate surface using surface tension and letting it stand for a certain period of time to develop (paddle method), spraying the developer onto the substrate surface (spray method), and continuously dispensing the developer while scanning a developer dispensing nozzle at a constant speed onto a substrate rotating at a constant speed (dynamic dispensing method). The development time is preferably 10 to 300 seconds, and more preferably 20 to 120 seconds. The temperature of the developer is preferably 0 to 50°C, and more preferably 15 to 35°C. In step (3), a step of stopping development while substituting with another solvent may be performed.

[0307] It is preferable to use an alkaline aqueous solution containing alkali as the alkaline developer. The type of alkaline aqueous solution is not particularly limited, but examples include alkaline aqueous solutions containing quaternary ammonium salts represented by tetramethylammonium hydroxide, inorganic alkalis, primary amines, secondary amines, tertiary amines, alcohol amines, or cyclic amines. Among these, it is preferable that the alkaline developer be an aqueous solution of a quaternary ammonium salt represented by tetramethylammonium hydroxide (TMAH). Appropriate amounts of alcohols, surfactants, etc., may be added to the alkaline developer. The alkali concentration of the alkaline developer is usually preferably 0.1 to 20% by mass. The pH of the alkaline developer is usually preferably 10.0 to 15.0.

[0308] The organic developer is preferably a developer containing at least one organic solvent selected from the group consisting of ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents.

[0309] The above organic solvents may be mixed in multiple quantities, or mixed with solvents other than the above organic solvents or with water. The water content of the organic developer as a whole is preferably less than 50% by mass, more preferably less than 20% by mass, even more preferably less than 10% by mass, and particularly preferably substantially water-free. The content of the organic solvent in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, even more preferably 90% by mass or more and 100% by mass or less, and particularly preferably 95% by mass or more and 100% by mass or less, based on the total amount of the organic developer.

[0310] The organic developer preferably contains butyl acetate (n-butyl acetate), and more preferably contains butyl acetate and a hydrocarbon having 9 to 12 carbon atoms. The hydrocarbon having 9 to 12 carbon atoms contained in the organic treatment solution may be just one type or two or more types. The hydrocarbon having 9 to 12 carbon atoms is preferably at least one selected from the group consisting of alkanes, alkenes, alkynes and cycloalkanes, more preferably an alkane, even more preferably at least one selected from the group consisting of nonanes, decanes, undecanes and dodecanes, particularly preferably at least one selected from the group consisting of undecanes and dodecanes, and most preferably undecanes. The hydrocarbon having 9 to 12 carbon atoms may also contain structural isomers.

[0311] The butyl acetate content in the organic developer is preferably 65% ​​to 99% by mass, more preferably 70% to 95% by mass, and even more preferably 75% to 90% by mass, based on 100% by mass of the entire organic developer. The hydrocarbon content (total amount if multiple hydrocarbons with 9 to 12 carbon atoms are included) in the organic developer is preferably 1% to 35% by mass, more preferably 5% to 30% by mass, and even more preferably 10% to 25% by mass, based on 100% by mass of the entire organic developer.

[0312] The mass ratio of butyl acetate to hydrocarbons having 9 to 12 carbon atoms in the organic developer (butyl acetate content / hydrocarbon content having 9 to 12 carbon atoms) is preferably 60 / 40 to 95 / 5, more preferably 70 / 30 to 95 / 5, even more preferably 80 / 20 to 90 / 10, and particularly preferably 90 / 10.

[0313] Organic developers may contain other components in addition to butyl acetate and hydrocarbons having 9 to 12 carbon atoms. Examples of other components include water, organic solvents other than butyl acetate and hydrocarbons having 9 to 12 carbon atoms, surfactants, antioxidants, and basic compounds.

[0314] [Rinsing Step] After step (3), rinsing may be performed. The rinsing solution is not particularly limited as long as it does not dissolve the pattern, and a solution containing a general solvent can be used. The rinsing solution preferably contains at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents.

[0315] The rinsing method is not particularly limited and includes, for example, a method in which rinsing liquid is continuously discharged onto a substrate rotating at a constant speed (rotary coating method), a method in which the substrate is immersed in a tank filled with rinsing liquid for a certain period of time (dip method), and a method in which rinsing liquid is sprayed onto the surface of the substrate (spray method).

[0316] Furthermore, the pattern formation method of the present invention may include a heating step (Post Bake) after step (3). This step removes any developer and rinse solution remaining between and inside the patterns. This step also has the effect of mellowing the resist pattern and improving the surface roughness of the pattern. The heating step after step (3) may be performed, for example, at 40 to 250°C (preferably 90 to 200°C) for, for example, 10 seconds to 3 minutes (preferably 30 seconds to 120 seconds).

[0317] Alternatively, the formed pattern may be used as a mask to perform an etching process on the substrate. In other words, the pattern formed in step (3) may be used as a mask to process the substrate (or the underlying film and substrate) to form a pattern on the substrate. The method of processing the substrate (or the underlying film and substrate) is not particularly limited, but a preferred method is to form a pattern on the substrate by performing dry etching on the substrate (or the underlying film and substrate) using the pattern formed in step (3) as a mask. Dry etching is not particularly limited, but oxygen plasma etching is preferred.

[0318] In the pattern forming method of the present invention, the developer, resist composition, and other various materials (e.g., solvent, rinse solution, anti-reflective film forming composition, top coat forming composition, etc.) used are preferably free of impurities such as metals. The impurity content in these materials is preferably 1 ppm (parts per million) or less, more preferably 10 ppb (parts per billion) or less, even more preferably 100 ppt (parts per trillion) or less, particularly preferably 10 ppt or less, and most preferably 1 ppt or less. The lower limit of the impurity content is not particularly limited and may be 0 ppt or more. Examples of metal impurities include Na, K, Ca, Fe, Cu, Mg, Al, Li, Cr, Ni, Sn, Ag, As, Au, Ba, Cd, Co, Pb, Ti, V, W, and Zn.

[0319] Methods for reducing impurities such as metals contained in various materials include, for example, selecting raw materials with a low metal content as constituent materials for various materials, performing filter filtration on the constituent materials of various materials, and performing distillation under conditions that suppress contamination as much as possible, such as by lining the inside of the apparatus with Teflon®. Details of filtration using filters are described in paragraph

[0321] of International Publication No. 2020 / 004306.

[0320] In addition to filter filtration, impurities may be removed using adsorbents, or a combination of filter filtration and adsorbents may be used. Known adsorbents can be used, such as inorganic adsorbents like silica gel and zeolite, and organic adsorbents like activated carbon. To reduce impurities such as metals contained in the above materials, it is necessary to prevent the introduction of metal impurities during the manufacturing process. Whether metal impurities have been sufficiently removed from the manufacturing equipment can be confirmed by measuring the content of metal components in the cleaning solution used to clean the equipment. The content of metal components in the cleaning solution after use is preferably 100 ppt by mass or less, more preferably 10 ppt by mass or less, and even more preferably 1 ppt by mass or less. There is no particular lower limit, but 0 ppt by mass or more is preferred.

[0321] [Method for Manufacturing Electronic Devices] This specification relates to a method for manufacturing electronic devices, including the pattern forming method of the present invention described above, and to electronic devices manufactured by this manufacturing method. Preferred embodiments of the electronic devices of this specification include those mounted on electrical and electronic equipment (home appliances, OA (Office Automation), media-related equipment, optical equipment, and communication equipment, etc.).

[0322] [Onium Salt Compounds] The present invention also relates to onium salt compounds represented by the following general formula (N-1).

[0323]

[0324] In the general formula (N-1), Ar represents an aromatic ring group. １ and R ２ Each of these independently represents a hydrogen atom, a halogen atom, or a monovalent organic group. X is -CO ２ － , -SO ２ NR １ R ２ Represents a monovalent substituent other than . m represents an integer of 0 or more. If m is an integer of 2 or more, multiple Xs may be the same or different, and multiple Xs may be linked to form a ring. n represents an integer of 1 or more. If n is an integer of 2 or more, multiple R １ and R ２These can be the same or different. r represents an integer greater than or equal to 1. Ma ｐ＋ represents a p-valent onium cation. p and q are independent integers greater than or equal to 1, where p × q = r.

[0325] In the general formula (N-1), Ar, R １ , R ２ ,X,m,n,r,Ma ｐ＋ , p, and q are Ar, R in the general formula (N-1) in the description of the onium salt compound (N) above. １ , R ２ ,X,m,n,r,Ma ｐ＋ It is synonymous with p and q, and the preferred examples are similar.

[0326] R in the general formula (N-1) １ and R ２ Preferably, at least one of them is a hydrogen atom.

[0327] In the general formula (N-1), -CO ２ － -SO ２ NR １ R ２ It is preferable that at least one of them is bonded.

[0328] It is preferable that at least one of the X in the general formula (N-1) contains a halogen atom.

[0329] Ma in general formula (N-1) ｐ＋ It is preferable that it contains a fluorine atom or an iodine atom.

[0330] The onium salt compound represented by general formula (N-1) is more preferably represented by general formula (N-2) and even more preferably by general formula (N-3).

[0331] The present invention will be described in more detail below based on examples. The materials, amounts used, proportions, processing content, and processing procedures shown in the following examples can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the examples shown below.

[0332] <Components of the Resist Composition> The components used in the preparation of the resist compositions used in the examples and comparative examples are shown below.

[0333] [Resin (P)] The resins (resins P-1 to P-32) shown in Table 2 below are described below. The resins used are synthesized according to known methods. Table 1 shows the composition of resins P-1 to P-32 (type of repeating unit, composition ratio of repeating units (mol% ratio), weight-average molecular weight (Mw), and degree of dispersion (Mw / Mn)). The weight-average molecular weight (Mw), number-average molecular weight (Mn), and polydispersity (Mw / Mn) of resins P-1 to P-32 were measured using GPC (Gel Permeation Chromatography) equipment (Tosoh Corporation, HLC-8120GPC) as polystyrene equivalent values ​​(solvent: tetrahydrofuran, flow rate (sample injection volume): 10 μL, column: Tosoh Corporation TSK gel Multipore HXL-M, column temperature: 40°C, flow rate: 1.0 mL / min, detector: differential refractive index detector). The composition ratio (mol% ratio) of the resins was also determined as follows: １３ It is determined by C-NMR (Nuclear Magnetic Resonance).

[0334]

[0335] The structures of monomers M-a-1 to M-a-13, M-b-1 to M-b-13, M-c-1 to M-c-20, and M-d-1 to M-d-4, which correspond to each repeating unit constituting the resin shown in Table 1, are shown below.

[0336]

[0337]

[0338]

[0339]

[0340] [Onium Salt Compounds (N)] The structures of the onium salt compounds ((I)-1 to (I)-30, and (Z)-1 to (Z)-2) shown in Table 2 below are shown below. Onium salt compound (I)-1 is used, synthesized by the synthesis method described later (Synthesis Example 1). Onium salt compounds (I)-2 to (I)-30, and (Z)-1 to (Z)-2 are used, synthesized in accordance with Synthesis Example 1 or by known methods. Note that onium salt compounds (Z)-1 to (Z)-2 are comparative compounds.

[0341]

[0342]

[0343]

[0344]

[0345]

[0346] <Synthesis Example 1: Synthesis of Onium Salt Compound (I)-1> (Synthesis of Compound (I)-1-A)

[0347]

[0348] 10.0 g of methyl 2-(aminosulfonyl)benzoate and 40 mL of water were added to 100 mL of tetrahydrofuran to obtain a mixture. 2.2 g of lithium hydroxide was added to the mixture, ensuring the temperature of the mixture did not exceed 25°C, and the mixture was stirred at room temperature (25°C) for 3 hours. After confirming the disappearance of methyl 2-(aminosulfonyl)benzoate, 1N hydrochloric acid was added until the pH of the reaction solution was 3 or less, and the product was extracted with ethyl acetate (80 mL). The obtained organic phase was washed with saturated sodium chloride aqueous solution (100 mL) and water (100 mL), and the solvent was removed by distillation to obtain compound (I)-1-A (8.4 g) (yield 90%). １ H-NMR (400MHz, DMSO-d6) 5.67 (brs, 2H), 7.92-8.04 (m, 3H), 8.16-8.20 (m, 1H).

[0349] (Synthesis of onium salt compound (I)-1)

[0350]

[0351] A mixture was obtained by mixing methylene chloride (150 mL) and water (150 mL). Sodium bicarbonate (2.5 g), compound (I)-1-A (5.0 g), and triphenylsulfonium bromide (8.53 g) were added to the mixture. After stirring the mixture for 1 hour, the aqueous phase was removed from the mixture. The organic layer was washed three times with water (150 mL), and the solvent was removed by distillation to obtain onium salt compound (I)-1 (9.2 g) (yield 80%). １ H-NMR (400MHz, DMSO-d6) δ7.55-7.59 (m, 3H), 7.62-7.66 (m, 1H), 7.77-7.92 (m, 15H).

[0352] Other onium salt compounds can be synthesized in a similar manner.

[0353] [Photoacid Generator (A)] The structures of the photoacid generators (A-1 to A-17) shown in Table 2 below are shown below. The photoacid generators (A-1 to A-17) are compounds that do not correspond to the onium salt compound (N).

[0354]

[0355]

[0356]

[0357] [Acid Diffusion Control Agent (B)] The structures of the acid diffusion control agents (B-1 to B-5) shown in Table 2 below are shown below. The acid diffusion control agents (B-1 to B-5) are compounds that do not correspond to the onium salt compound (N).

[0358]

[0359] [Surfactants (C)] The surfactants (C-1 to C-3) shown in Table 2 below are listed below. C-1: Megafac F176 (manufactured by DIC Corporation, fluorine-based surfactant) C-2: Megafac R08 (manufactured by DIC Corporation, fluorine and silicone-based surfactant) C-3: PF656 (manufactured by OMNOVA, fluorine-based surfactant)

[0360] [Solvent (D)] The solvents (solvents D-1 to D-9) shown in Table 2 below are listed below. D-1: Propylene glycol monomethyl ether acetate (PGMEA) D-2: Propylene glycol monomethyl ether (PGME) D-3: Propylene glycol monoethyl ether (PGEE) D-4: Cyclohexanone D-5: Cyclopentanone D-6: 2-heptanone D-7: Ethyl lactate D-8: γ-butyrolactone D-9: Propylene carbonate

[0361] [Preparation of Resist Composition] Mix each component shown in Table 2 so that the solid content concentration is 1.3% by mass. Then, filter the resulting mixture through a polyethylene filter with a pore size of 0.03 μm to prepare the resist compositions (Re-1 to Re-32, Re-C1 to Re-C2). Note that "solid content" refers to all components other than the solvent. The obtained resist compositions are used in the examples and comparative examples. In the table, the "Content" column indicates the content (by mass) of each component relative to the total solid content in the resist composition. The solvent mixing ratio refers to the proportion (by mass) of each solvent when the total solvent is set to 100.

[0362]

[0363] [Pattern Formation and Evaluation (1)] [EUV Exposure, Alkaline Development, Examples 1a-32a, Comparative Examples 1a-2a]

[0364] A base layer formation composition AL412 (manufactured by Brewer Science) is applied to a silicon wafer and baked at 205°C for 60 seconds to form a base layer with a thickness of 20 nm. A resist composition immediately after preparation, as shown in Table 3, is applied on top of the base layer and baked at 100°C for 60 seconds to form a resist film with a thickness of 30 nm. Pattern irradiation is performed on the silicon wafer having the obtained resist film using an EUV exposure apparatus (Exitech Micro Exposure Tool, NA 0.3, Quadrupol, outer sigma 0.68, inner sigma 0.36). A mask with a line size of 25 nm and a line-to-space ratio of 1:1 is used as the reticle. After exposure, the resist film is baked at 90°C for 60 seconds, then developed with an aqueous solution of tetramethylammonium hydroxide (2.38% by mass) for 30 seconds, followed by rinsing with pure water for 30 seconds. This is then spin-dried to obtain a positive-type pattern.

[0365] [Evaluation] <Temporal Stability> The irradiation energy required to resolve a 1:1 line-and-space pattern with a line width of 25 nm is defined as sensitivity (Eop1). Next, the resist composition is stored at room temperature (25°C) for one month. Then, a pattern is formed using the stored resist composition in the same manner as above, and the irradiation energy required to resolve a 1:1 line-and-space pattern with a line width of 25 nm is defined as sensitivity (Eop2). The difference between Eop1 and Eop2 is defined as the sensitivity variation and is evaluated according to the following criteria.

[0366] (Evaluation criteria) A: Sensitivity variation is 0.5 mJ / cm ２ Less than B: Sensitivity variation of 0.5 mJ / cm ２ 1.0 mJ / cm or more ２ Less than C: Sensitivity variation of 1.0 mJ / cm ２ 1.5mJ / cm or more ２ Less than D: Sensitivity variation of 1.5 mJ / cm ２ 2.0 mJ / cm or more ２ Less than X: Sensitivity variation of 2.0 mJ / cm ２ That's all.

[0367]

[0368] [Pattern Formation and Evaluation (2)] [EUV Exposure, Organic Solvent Development, Examples 1b-32b, Comparative Examples 1b-2b] An underlayer film formation composition AL412 (manufactured by Brewer Science) is applied to a silicon wafer and baked at 205°C for 60 seconds to form an underlayer film with a thickness of 20 nm. A resist composition shown in Table 4 is applied on top of the underlayer film and baked at 100°C for 60 seconds to form a resist film with a thickness of 30 nm. Pattern irradiation is performed on the silicon wafer having the obtained resist film using an EUV exposure apparatus (Exitech, Micro Exposure Tool, NA 0.3, Quadrupol, outer sigma 0.68, inner sigma 0.36). A mask with a line size of 25 nm and a line:space ratio of 1:1 is used as the reticle. After exposure, the resist film is baked at 90°C for 60 seconds, then developed with developer R shown in Table 4 for 30 seconds, and then spin-dried to obtain a negative-type pattern.

[0369] [Evaluation] The time-dependent stability will be evaluated using the same method as described above.

[0370]

[0371] The developer R in Table 4 is shown in Table 5 below.

[0372]

[0373] As shown in Tables 3 and 4 above, the resist composition of the present invention can form a pattern with minimal sensitivity fluctuations due to storage over time. On the other hand, the resist composition of the comparative example exhibits insufficient performance in this regard.

[0374] According to the present invention, it is possible to provide a photosensitive or radiation-sensitive resin composition capable of forming a pattern with little sensitivity variation due to storage of the composition over time, a resist film formed from the photosensitive or radiation-sensitive resin composition, a pattern formation method and a method for manufacturing an electronic device using the photosensitive or radiation-sensitive resin composition, and an onium salt compound that can be suitably used in the photosensitive or radiation-sensitive resin composition.

[0375] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on Japanese Patent Application No. 2024-169311, filed on 27 September 2024, the contents of which are incorporated herein by reference.

Claims

1. A photosensitive or radiation-sensitive resin composition comprising an onium salt compound (N) represented by the following general formula (N-1), a resin whose polarity changes by the action of an acid, and a solvent. In the general formula (N-1), Ar represents an aromatic ring group. R １ and R ２ each independently represent a hydrogen atom, a halogen atom, or a monovalent organic group. X is -CO ２ － ,-SO ２ NR １ R ２ represents a monovalent substituent other than. m represents an integer of 0 or more. When m is an integer of 2 or more, a plurality of Xs may be the same or different, and a plurality of Xs may be linked to form a ring. n represents an integer of 1 or more. When n is an integer of 2 or more, a plurality of R １ and R ２ may be the same or different from each other. r represents an integer of 1 or more. Ma ｐ＋ represents a p-valent onium cation. p and q each independently represent an integer of 1 or more. However, p×q = r is satisfied.

2. R in the general formula (N-1) １ and R ２ The photosensitive or radiation-sensitive resin composition according to claim 1, wherein at least one of the atoms is a hydrogen atom.

3. In the above general formula (N-1), -CO ２ － -SO ２ NR １ R ２ The photosensitive or radiation-sensitive resin composition according to claim 1, wherein at least one of the following is bonded.

4. The photosensitive or radiation-sensitive resin composition according to claim 1, wherein at least one of X in the general formula (N-1) contains a halogen atom.

5. Ma in the general formula (N-1) ｐ＋ The photosensitive or radiation-sensitive resin composition according to claim 1, wherein the composition contains a fluorine atom or an iodine atom.

6. The photosensitive or radiation-sensitive resin composition according to claim 1, wherein the resin comprises repeating units having aromatic rings.

7. The photosensitive or radiation-sensitive resin composition according to claim 1, wherein the resin comprises repeating units having hydroxyl groups bonded to an aromatic ring.

8. A resist film formed using the photosensitive or radiation-sensitive resin composition according to any one of claims 1 to 7.

9. A pattern forming method comprising the steps of: forming a resist film on a substrate using the photosensitive or radiation-sensitive resin composition described in any one of claims 1 to 7; exposing the resist film; and developing the exposed resist film using a developer to form a pattern.

10. A method for manufacturing an electronic device, comprising the pattern forming method described in claim 9.

11. Onium salt compounds represented by the following general formula (N-1). In the general formula (N-1), Ar represents an aromatic ring group. １ and R ２ Each of these independently represents a hydrogen atom, a halogen atom, or a monovalent organic group. X is -CO ２ － , -SO ２ NR １ R ２ Represents a monovalent substituent other than . m represents an integer of 0 or more. If m is an integer of 2 or more, multiple Xs may be the same or different, and multiple Xs may be linked to form a ring. n represents an integer of 1 or more. If n is an integer of 2 or more, multiple R １ and R ２ These can be the same or different. r represents an integer greater than or equal to 1. Ma ｐ＋ represents a p-valent onium cation. p and q are independent integers greater than or equal to 1, where p × q = r.

12. R in the above general formula (N-1) １ and R ２ The onium salt compound according to claim 11, wherein at least one of the atoms is a hydrogen atom.

13. In the above general formula (N-1), -CO ２ － -SO ２ NR １ R ２ The onium salt compound according to claim 11 or 12, wherein at least one of the following is bonded.

14. The onium salt compound according to claim 11 or 12, wherein at least one of X in the general formula (N-1) contains a halogen atom.

15. Ma in the general formula (N-1) ｐ＋ The onium salt compound according to claim 11 or 12, wherein the compound contains a fluorine atom or an iodine atom.

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