Actinic ray-sensitive or radiation-sensitive resin composition, resist film, pattern formation method, and electronic device production method

Abstract

The present invention addresses the problem of providing an actinic ray-sensitive or radiation-sensitive resin composition capable of forming a pattern with small LWR even after long-term storage. An actinic ray-sensitive or radiation-sensitive resin composition according to the present invention contains: a first acid generator that generates, by the action of actinic rays or radiation, an acid represented by formula (1) and having a pKa of less than -0.75; a resin having a repeating unit represented by formula (P1); a second acid generator that generates, by the action of actinic rays or radiation, an acid having a pKa of -0.75 or more; and at least one specific compound selected from the group consisting of second compounds that generate, by the action of actinic rays or radiation, a compound that contains a nitrogen atom bonded to three atoms selected from carbon and hydrogen atoms, and a sulfonic acid group, the compound being different from the acid represented by the formula (1).

Description

Photosensitive or radiation-sensitive resin composition, resist film, pattern forming method, method for manufacturing electronic devices

[0001] The present invention relates to a photosensitive or radiation-sensitive resin composition, a resist film, a pattern forming method, and a method for manufacturing an electronic device.

[0002] Conventionally, in the manufacturing processes of semiconductor devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations), microfabrication has been performed using lithography with photosensitive or radiation-sensitive resin 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 g-line to i-line, and further to KrF excimer laser light, and 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, so-called immersion methods have been developed, 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 also being developed. Accordingly, compositions that are effectively sensitive to various types of active light or radiation are being developed.

[0004] As an example of such a composition, Patent Document 1 discloses a composition comprising a resin whose solubility in a developer changes due to the action of an acid, and a photoacid generator component having a predetermined sulfonic acid type onium salt structure.

[0005] International Publication No. 2024 / 117106

[0006] When the inventors examined the compositions specifically disclosed in the above-mentioned literature, they found that when used after long-term storage, patterns with a small LWR (Line Width Roughness) could not be formed, indicating that there is room for improvement.

[0007] Therefore, the present invention aims to provide a photosensitive or radiation-sensitive resin composition that can form patterns with low LWR even after long-term storage. Furthermore, the present invention aims to provide a resist film, a pattern formation method, and a method for manufacturing an electronic device related to the above-mentioned photosensitive or radiation-sensitive resin composition.

[0008] As a result of diligent research to solve the above problems, the inventors have found that the problems can be solved by the following configuration.

[0009] [1] A photosensitive or radiation-sensitive resin composition comprising: a first acid generator that generates an acid represented by formula (1) described later and having a pKa of less than -0.75 upon the action of active light or radiation; a resin having repeating units represented by formula (P1) described later; a second acid generator that generates an acid with a pKa of -0.75 or higher upon the action of active light or radiation; and at least one specific compound selected from the group comprising a second compound that generates a compound different from the acid represented by formula (1) upon the action of active light or radiation, comprising a nitrogen atom bonded to three atoms selected from carbon atoms and hydrogen atoms, and a sulfonic acid group. [2] The photosensitive or radiation-sensitive resin composition according to [1], wherein the specific compound comprises a compound represented by any of formulas (D1) to (D5) described later. [3] The photosensitive or radiation-sensitive resin composition according to [1] or [2], wherein in formula (1) above, X is a fluorine atom or a monovalent hydrocarbon group having a fluorine atom. [4] The photosensitive or radiation-sensitive resin composition according to any one of [1] to [3], wherein the acid represented by formula (1) above has an alicyclic structure. [5] In formulas (D1) to (D5) above, R Ｎ１ This is an avalence aliphatic group containing a nitrogen atom bonded to three atoms selected from the carbon and hydrogen atoms mentioned above, and R ｄ１ R is an avalence aliphatic group that does not contain a nitrogen atom and is bonded to three atoms selected from the carbon and hydrogen atoms mentioned above, ｄ２ , R ｄ３ , and R ｄ５ However, each is independently an a-valent aliphatic group, R ｄ４ , R ａ６and R ｄ７ are each independently a monovalent aliphatic group, the actinic ray-sensitive or radiation-sensitive resin composition according to [2]. [6] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [5], wherein T in the formula (P1) is a single bond. [7] In the formula (1), L １ is -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ - or -CR Ｌ４ R Ｌ５ -, the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [6]. [8] In the formula (1), L １ is -O-CR Ｌ１ R Ｌ２ -, -S- or -SO ２ -, the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [7]. [9] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [8], wherein the specific compound comprises a compound represented by any one of the formulae (D1) to (D3).

[10] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [9], wherein the first acid generator comprises a sulfonium cation or an iodonium cation.

[11] A resist film formed using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to

[10] .

[12] A pattern forming method comprising: a step of forming a resist film on a substrate using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to

[10] ; a step of exposing the resist film; and a step of developing the exposed resist film with a developer to form a pattern.

[13] A method for manufacturing an electronic device, comprising the pattern forming method according to

[12] .

[0010] According to the present invention, there can be provided an actinic ray-sensitive or radiation-sensitive resin composition capable of forming a pattern with a small LWR even after long-term storage. Further, according to the present invention, there can also be provided a resist film, a pattern forming method, and a method for manufacturing an electronic device, which relate to the actinic ray-sensitive or radiation-sensitive resin composition.

[0011] The present invention will be described in detail below. The following descriptions of constituent elements may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.

[0012] In this specification, a numerical range expressed using "~" means a range that includes the numbers written before and after "~" as the lower and upper limits. Also in this specification, if there are two or more types of a component, the "content" of that component means the total content of those two or more types of components. In this specification, in numerical ranges described in steps, the upper or lower limit stated in one numerical range may be replaced with the upper or lower limit of another numerical range described in steps. Also, in numerical ranges described in this specification, the upper or lower limit stated in one numerical range may be replaced with the value shown in the example. In this specification, a combination of two or more preferred embodiments is a more preferred embodiment.

[0013] 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.

[0014] In this specification, the weight-average molecular weight (Mw), number-average molecular weight (Mn), and polydispersity (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).

[0015] In this specification, pKa (acid dissociation constant) refers to the pKa in an aqueous solution at 25°C, and specifically, it is a value calculated using the following software package 1 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). If the pKa in an aqueous solution cannot be calculated, the "pKa in dimethyl sulfoxide (DMSO) solution" will be used. Furthermore, if the pKa cannot be calculated using the above method, the value obtained by molecular orbital calculation will be used. As a specific method using molecular orbital calculations, we adopt values ​​obtained using Gaussian 16 based on DFT.

[0016] In this specification, when there are multiple substituents and linking groups (hereinafter referred to as substituents, etc.) indicated by specific symbols, or when multiple substituents, etc. are specified simultaneously, it means that each substituent, etc. may be identical or different from the others. The same applies to the specification of the number of substituents, etc. In this specification, the bonding direction of a divalent group (e.g., -CO-O-) as expressed is not limited unless otherwise specified. For example, if Y in a compound represented by the formula "X-Y-Z" is -CO-O-, the compound may be "X-O-CO-Z" or "X-CO-O-Z".

[0017] In this specification, "aliphatic group" refers to an organic group that does not contain an aromatic ring. "Organic group" refers to a group that contains at least a carbon atom and a hydrogen atom. Unless otherwise specified, an aliphatic group may have a heteroatom. Preferred heteroatoms that the aliphatic group may have include oxygen, sulfur, selenium, tellurium, nitrogen, phosphorus, boron, silicon, or halogen atoms. Also, unless otherwise specified, an aliphatic group may have an unsaturated bond (for example, an unsaturated bond containing heteroatoms such as -CO- and -SO-, and a carbon-carbon unsaturated bond such as a vinylene group), as long as it does not contain an aromatic ring. In this specification, "alicyclic structure" refers to an organic ring structure that does not exhibit aromaticity. "Organic ring" refers to a ring that contains at least a carbon atom and a hydrogen atom. Unless otherwise specified, an alicyclic structure may have a heteroatom. Preferred heteroatoms that an alicyclic structure may have include the preferred heteroatoms that the aliphatic group may have. Furthermore, unless otherwise specified, the alicyclic structure may have linking groups containing heteroatoms such as -CO- and -SO- as part of the ring, as long as it does not exhibit aromaticity, and may also have unsaturated bonds (for example, carbon-carbon unsaturated bonds such as vinylene groups).

[0018] In this specification, "solids" refers to components that form a film (e.g., a resist film), and does not include solvents. Furthermore, any component that forms a film is considered a solid, even if its properties are liquid.

[0019] [Photosensitive or Radiation-Sensitive Resin Composition] The photosensitive or radiation-sensitive resin composition of the present invention (hereinafter also simply referred to as the "resist composition") will be described in detail below. The resist composition of the present invention (hereinafter also simply referred to as the "resist composition") comprises a first acid generator that generates an acid represented by formula (1) described later and having a pKa of less than -0.75 (hereinafter also referred to as the "first acid"), a resin having repeating units represented by formula (P1) described later (hereinafter also referred to as the "specific resin"), a second acid generator that generates an acid with a pKa of -0.75 or higher (hereinafter also referred to as the "second acid") by the action of active light or radiation, and at least one specific compound selected from the group consisting of a second compound that generates a compound different from the acid represented by formula (1) above, by the action of active light or radiation, comprising a nitrogen atom bonded to three atoms selected from carbon atoms and hydrogen atoms, and a sulfonic acid group.

[0020] The reason why the resist composition having the above configuration can solve the problems of the present invention is not necessarily clear, but the inventors speculate as follows. Note 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. In this resist composition, the specific resin has a predetermined repeating unit having a monocyclic structure that is prone to polarity changes due to the action of an acid. Furthermore, the first acid generator is a photoacid generator that generates a first acid, which is a predetermined aromatic sulfonic acid, and the specific compound is a compound that can control the diffusion of the first acid in the resist film. Due to the action of these components contained in this resist composition, the polarity of this resist composition changes locally efficiently and accurately upon exposure, allowing the formation of a pattern with a low LWR. Furthermore, the first acid generator has a structure that is resistant to decomposition by the action of bases, etc., and the specific compound has a structure that is resistant to decomposition of the first acid generator. Therefore, even when this resist composition is stored for a long period, decomposition of the first acid generator is unlikely to occur. As a result, it is presumed that this resist composition can form a pattern with a low LWR even after long-term storage. Hereinafter, the ability to form a pattern with a smaller LWR even after long-term storage will also be referred to simply as "the effect of the present invention is superior." Below, each component that may be included in this resist composition will be described in detail.

[0021] [First Acid Generator] This resist composition contains a first acid generator, which is a compound that generates a first acid represented by formula (1) and having a pKa of less than -0.75 upon the action of active light or radiation.

[0022] <First Acid> The first acid is the acid represented by formula (1).

[0023]

[0024] In formula (1), R １ R represents an n-valent aliphatic group. １ The n-valent aliphatic group represented by may, for example, have a nitrogen atom, and one or more methylene groups may be -O-, -CO-, -S-, -SO-, and -SO ２Examples include n-valent aliphatic hydrocarbon groups which may be substituted with a group selected from the group consisting of -. The number of carbon atoms of the above n-valent aliphatic group is preferably 3 to 30, more preferably 5 to 24, and even more preferably 6 to 18.

[0025] The above n-valent aliphatic group may be linear or may contain an alicyclic structure, and it is preferable that it contains an alicyclic structure in that the effects of the present invention are superior. In this specification, when a particular group contains an alicyclic structure, the group may be an alicyclic group or a group formed by combining an alicyclic group and a linear group (for example, a group having an alicyclic group at the end of a linear group, and a group having an alicyclic group in the middle of a linear group). Furthermore, an alicyclic group is intended to be a group formed by removing one or more hydrogen atoms from an alicyclic structure. The above alicyclic structure may be monocyclic or polycyclic, with polycyclic being preferred. The number of carbon atoms in the above alicyclic structure is preferably 6 or more, and more preferably 10 or more. There is no particular upper limit, but it is often 30 or less, and preferably 20 or less. The above alicyclic structure may be either an aliphatic hydrocarbon ring or an aliphatic heterocycle. The above alicyclic structure may, for example, have a nitrogen atom as a ring member atom, and one or more of the methylene groups constituting the ring skeleton may be -O-, -CO-, -S-, -SO-, and -SO ２ Examples of aliphatic hydrocarbon rings may be substituted with a group selected from the group consisting of -. Specific examples of the above alicyclic structure include monocyclic aliphatic hydrocarbon rings such as cyclohexane, cyclopentane, cyclooctane, and cyclohexene; adamantane, norbornane, norbornene, tricyclo[5.2.1.0 ２，６ Examples include polycyclic aliphatic hydrocarbon rings such as decane and tricyclododecane; cycloalkanones such as cyclohexanone and adamantanone; cycloalkenones; lactone-containing rings including lactone structures; sultone-containing rings including sultone structures; nitrogen-containing aliphatic heterocycles such as piperidine, decahydroquinoline, and decahydroisoquinoline; cyclic ethers such as tetrahydrofuran and tetrahydropyran; cyclic thioethers such as tetrahydrothiophene and thian; and alicyclic rings having a steroid skeleton. Suitable alicyclic structures include alicyclic rings represented by the following formulas (c-1) to (c-6).

[0026]

[0027] In formulas (c-1) to (c-6), W １ Each of these independently represents an alkylene group having 1 to 5 carbon atoms that may have -O-, -S-, or -O- or -S-. An example of an alkylene group having 1 to 5 carbon atoms that may have -O- or -S- is -O-CH ２ -ien-CH ２ -O-CH ２ -, -S-CH ２ -, and -CH ２ -S-CH ２ - is one example. W １ As such, -O-, -S-, or a methylene group is preferred. ２ is -O-, -S-, -SO ２ -, -CO-, -NH-, -CO-O-, or -SO ２ -O- represents nw, which represents an integer between 0 and 2.

[0028] In formula (1), L １ These are, independently, -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ -, -NR Ｌ３ -, -O-CO-O-, or -CR Ｌ４ R Ｌ５ - represents the effect of the present invention, and -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ - or -CR Ｌ４ R Ｌ５ - is preferred, -O-CR Ｌ１ R Ｌ２ -, -S-, or -SO ２ - is preferable. R Ｌ１ ~R Ｌ５ Each of these independently represents a hydrogen atom, a monovalent aliphatic group, a halogen atom, or a cyano group. Ｌ１ ~R Ｌ５The above monovalent aliphatic group represented by may, for example, have a nitrogen atom, and one or more methylene groups may be -O-, -CO-, -S-, -SO-, and -SO ２ Examples include monovalent aliphatic hydrocarbon groups which may be substituted with a group selected from the group consisting of -. The number of carbon atoms of the above monovalent aliphatic group is preferably 1 to 30, more preferably 1 to 24, and even more preferably 1 to 18. The above monovalent aliphatic group may be in the form of a chain or may contain an alicyclic structure. The definition and preferred embodiments of the alicyclic structure which the monovalent aliphatic group may contain are described above in R １ This is the same as the alicyclic structure that an n-valent aliphatic group represented by may have.

[0029] In formula (1), L １ ga-O-CR Ｌ１ R Ｌ２ - If R １ , R Ｌ１ , and R Ｌ２ Two or more selected from may be bonded to each other to form an alicyclic ring which may have substituents, L １ ga-NR Ｌ３ - If R １ and R Ｌ３ They may be bonded to each other to form an alicyclic ring which may have substituents, L １ ga-CR Ｌ４ R Ｌ５ - If R １ , R Ｌ４ , and R Ｌ５ Two or more selected from may be bonded to each other to form an alicyclic ring which may have substituents. The definition and preferred embodiments of the above alicyclic ring are as described above in R １This is the same as the alicyclic structure that an n-valent aliphatic group represented by may have. As substituents that may be present in the above alicyclic, substituents that do not contain aromatic rings are preferred. Examples of substituents that do not contain aromatic rings include alkyl groups (e.g., 1 to 15 carbon atoms, preferably 1 to 6 carbon atoms), cycloalkyl groups (e.g., 3 to 15 carbon atoms, preferably 3 to 6 carbon atoms), alkoxy groups (e.g., 1 to 15 carbon atoms, preferably 1 to 6 carbon atoms), hydroxyl groups, carboxyl groups, alkyloxycarbonyl groups (e.g., 2 to 15 carbon atoms, preferably 2 to 7 carbon atoms), alkylcarbonyloxy groups (e.g., 2 to 15 carbon atoms, preferably 2 to 7 carbon atoms), alkylsulfinyl groups, alkylsulfonyl groups, alkylthio groups, and halogen atoms, with alkyl groups being preferred. For example, the first acid is n=1 and L １ ga-O-CR Ｌ１ R Ｌ２ - If so, it may be an acid represented by formula (1-c1) or formula (1-c2), n=1, and L １ ga-NR Ｌ３ - If this is the case, the acid may be represented by formula (1-c3), n=1, and L ３ ga-CR Ｌ１ R Ｌ２ If the acid is negative, it may be an acid represented by formula (1-c4) or formula (1-c5).

[0030]

[0031] In equations (1-c1) to (1-c5), Ar, X, and s are the same as Ar, X, and s in equation (1), respectively. １ , C ３ , and C ４ Each of these independently represents an alicyclic ring which may have substituents. ２ and C ５ Each of these independently represents a polycyclic alicyclic ring which may have substituents. ２ The atom that bonds with the adjacent oxygen atom in the alicyclic ring represented by is a carbon atom. Also, C ５ The atom bonded to the adjacent Ar in the alicyclic ring represented by is a carbon atom. Details of the above alicyclic ring and the substituents that the alicyclic ring may have are as described above.ｃ１ represents R １ or R Ｌ１ and R ｃ２ represents R １ or R Ｌ４ . R １ , R Ｌ１ and R Ｌ４ are each the same as R １ , R Ｌ１ and R Ｌ４ in Formula (1).

[0032] In Formula (1), each Ar independently represents an s+2-valent aromatic ring group. The aromatic ring group may be either monocyclic or polycyclic. The aromatic ring group may be either an aromatic hydrocarbon group or an aromatic heterocyclic group, with an aromatic hydrocarbon ring group being preferred. Examples of the aromatic hydrocarbon group include aromatic hydrocarbon ring groups having 6 to 18 carbon atoms such as a benzene ring group, a naphthalene ring group, an anthracene ring group, and a naphthacene ring group. The aromatic heterocyclic group preferably contains at least one heteroatom selected from a nitrogen atom, an oxygen atom, and a sulfur atom as ring member atoms. Examples of the aromatic heterocyclic group include aromatic heterocyclic groups having 4 to 20 ring member atoms such as a thiophene ring group, a furan ring group, a pyridine ring group, a pyrrole ring group, a benzothiophene ring group, a benzofuran ring group, a benzopyrrole ring group, a triazine ring group, an imidazole ring group, a benzimidazole ring group, a triazole ring group, a thiadiazole ring group, and a thiazole ring group. Among these, a benzene ring group or a naphthalene ring group is preferred as the aromatic ring group.

[0033] In formula (1), X independently represents a halogen atom or a monovalent hydrocarbon group having a halogen atom. Examples of halogen atoms in X include fluorine, chlorine, bromine, and iodine atoms, with fluorine being preferred. The monovalent hydrocarbon group may be linear, branched, or cyclic, with linear or branched being preferred. Examples of the monovalent hydrocarbon group include alkyl groups (preferably having 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms), alkenyl groups (preferably having 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms), alkynyl groups (preferably having 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms), and aryl groups (preferably having 6 to 10 carbon atoms), with alkyl groups being preferred. As for the monovalent hydrocarbon group having a halogen atom, a monovalent hydrocarbon group having a fluorine atom is preferred, and a perfluoroalkyl group is more preferred. X is preferably a fluorine atom or a monovalent hydrocarbon group having a fluorine atom, more preferably a fluorine atom or a trifluoromethyl group, and even more preferably a fluorine atom.

[0034] In formula (1), s represents an integer of 1 or more, preferably an integer of 2 or more, and more preferably an integer of 3 or more. The upper limit of s is not particularly limited as long as it is permissible by the valence of the aromatic ring group represented by Ar, and may be an integer of 8 or less, an integer of 6 or less, or an integer of 4 or less. For example, when Ar is a benzene ring group, s is an integer from 1 to 4. In particular, it is also preferable that s is the upper limit permissible by the valence of the aromatic ring group represented by Ar.

[0035] In formula (1), n ​​represents an integer of 1 or more, preferably an integer between 1 and 3, more preferably 1 or 2, and even more preferably 1.

[0036] In terms of achieving superior effects of the present invention, the first acid preferably has an alicyclic structure. The definition and preferred embodiment of the above alicyclic structure are described in R above. １ This is the same as the alicyclic structure that an n-valent aliphatic group represented by may have. Note that if the first acid has an alicyclic structure, R １ and R Ｌ１ ~R Ｌ５ Either of them may have an alicyclic structure, RＬ１ , R Ｌ２ , and R １ Two or more selected from may be bonded to each other to form an alicyclic ring which may have substituents, R Ｌ３ and R １ They may be bonded to each other to form an alicyclic ring which may have substituents, R Ｌ４ , R Ｌ５ , and R １ Two or more of these may be bonded to each other to form an alicyclic ring, which may have substituents. If the first acid has an alicyclic structure, the number of alicyclic structures in the first acid is preferably 1 to 3, and more preferably 1 or 2. A polycyclic alicyclic structure is counted as 1. For example, if the first acid has only adamantane as an alicyclic structure, the number of polycyclic alicyclic structures in the first acid is 1.

[0037] The first acid is also preferably an acid represented by any of the following: formula (1-1), formula (1-c1) described above, and formula (1-c3) described above.

[0038]

[0039] In equation (1-1), Ar, X, and s are the same as Ar, X, and s in equation (1), respectively. ２ is -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ -, -NR Ｌ３ -, -O-CO-O-, or -CR Ｌ４ R Ｌ５ Represents -. R Ｌ１ ~R Ｌ５ Each of these independently represents a hydrogen atom, a monovalent aliphatic group, a halogen atom, or a cyano group. Ｌ１ ~R Ｌ５ The details are as described above.

[0040] In formula (1-1), L ３ These are single bonds, or alkylene groups, -O-, -S-, -SO-, -SO ２ -, -NR Ｎ -, -CO-, or a combination thereof, representing a single bond, or an alkylene group, -O-, -CO-, -SO２ - or a combination thereof is preferred, and this includes a single bond, an alkylene group, -alkylene group-O-CO-alkylene group-, -O-CO-, or -SO ２ - is preferable. R Ｎ represents a hydrogen atom or a monovalent aliphatic group. The alkylene group may be linear or branched. The number of carbon atoms in the alkylene group is preferably 1 to 12, and more preferably 1 to 6.

[0041] In formula (1-1), R ２ Herein stands for monovalent alicyclic group, which may have substituents that do not contain an aromatic ring, or monovalent linear aliphatic hydrocarbon group, preferably a monovalent alicyclic group, which may have substituents that do not contain an aromatic ring. The above monovalent alicyclic group may be monocyclic or polycyclic, with polycyclic being preferred. The above monovalent alicyclic group may be either an aliphatic hydrocarbon ring group or an aliphatic heterocyclic group. An example of the above monovalent alicyclic group is a group obtained by removing one hydrogen atom from the above-described alicyclic structure. Examples of substituents that do not contain the aromatic ring include alkyl groups (e.g., 1 to 15 carbon atoms, preferably 1 to 6 carbon atoms), cycloalkyl groups (e.g., 3 to 15 carbon atoms, preferably 3 to 6 carbon atoms), alkoxy groups (e.g., 1 to 15 carbon atoms, preferably 1 to 6 carbon atoms), hydroxyl groups, carboxyl groups, alkyloxycarbonyl groups (e.g., 2 to 15 carbon atoms, preferably 2 to 7 carbon atoms), alkylcarbonyloxy groups (e.g., 2 to 15 carbon atoms, preferably 2 to 7 carbon atoms), alkylsulfinyl groups, alkylsulfonyl groups, alkylthio groups, and halogen atoms, with alkyl groups being preferred. The groups exemplified above as substituents may, if possible, have further substituents exemplified above. The number of carbon atoms in the monovalent alicyclic group, which may have substituents that do not contain the aromatic ring, is preferably 3 to 30, more preferably 5 to 24, and even more preferably 6 to 18. The monovalent linear aliphatic hydrocarbon group may be linear or branched. The number of carbon atoms in the above monovalent chain-like aliphatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 24, and even more preferably 6 to 18.

[0042] The molecular weight of the first acid is preferably 250 to 1000, more preferably 275 to 900, and even more preferably 300 to 800.

[0043] The pKa of the first acid is less than -0.75, preferably -0.80 or less, more preferably -1.50 or less, and even more preferably -1.70 or less. The lower limit of the pKa of the first acid is not particularly limited, but is often -10.00 or higher, preferably -7.50 or higher, and more preferably -5.00 or higher. If the first acid has a pKa of 2 or more (for example, when n is an integer of 2 or more), it is sufficient that the lowest pKa value is within the above range, and it is more preferable that all pKa values ​​are within the above range.

[0044] The first acid generator is not particularly limited as long as it is a compound that generates the first acid by the action of active light or radiation, but the sulfonic acid group (-SO) of the first acid is important. ３ It is preferable that the onium salt contains an anion formed by removing a hydrogen atom from H) and a cation.

[0045] Furthermore, the anion obtained by removing a hydrogen atom from the sulfonic acid group of the first acid is an n-valent anion represented by formula (1A).

[0046]

[0047] In formula (1A), R １ , L １ Ar, X, s, and n are R in equation (1), respectively. １ , L １ It is synonymous with Ar, X, s, and n.

[0048] The cation that the first acid generator may contain is not particularly limited, but an organic cation is preferred. As for the organic cation, a sulfonium cation or an iodonium cation is preferred. That is, the first acid generator preferably contains a sulfonium cation or an iodonium cation. The valency of the cation may be monovalent or divalent or higher, but monovalent is preferred.

[0049] The sulfonium cation is preferably a cation represented by formula (ZaI) (hereinafter also referred to as "cation (ZaI)"). The iodonium cation is preferably a cation represented by formula (ZaII) (hereinafter also referred to as "cation (ZaII)").

[0050]

[0051] In the 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 represented by 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 one example. When this resist composition is used as an EUV resist, R ２０１ ~R ２０５ It is preferable that 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).

[0052] 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 ~R２０３ 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.

[0053] 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.

[0054] 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, arylthio 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. The 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.

[0055] Next, we will explain the cation (ZaI-2). The cation (ZaI-2) is R in formula (ZaI). ２０１ ~R ２０３ However, each of these independently represents a cation that is an organic group without an aromatic ring. 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.

[0056] R ２０１ ~R ２０３Examples 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 The alkyl and cycloalkyl groups represented by may be further substituted with halogen atoms, alkoxy groups (e.g., C1-C5), hydroxyl groups, cyano groups, or nitro groups.

[0057] Next, we will explain the cation (ZaI-3b). The cation (ZaI-3b) is a cation represented by the following formula (ZaI-3b).

[0058]

[0059] 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 ７ｃ Each 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.

[0060] 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 Rｙ 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 polyrings formed by combining two or more of these rings. Examples of rings include 3- to 10-membered rings, preferably 4- to 8-membered rings, and more preferably 5- or 6-membered rings.

[0061] 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.

[0062] 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.

[0063] Next, we will explain the cation (ZaI-4b). The cation (ZaI-4b) is a cation represented by the following formula (ZaI-4b).

[0064]

[0065] In equation (ZaI-4b), l represents an integer from 0 to 2, and r represents an integer from 0 to 8. １３R 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 R １５ 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.

[0066] In formula (ZaI-4b), R １３ , R １４ , and R １５ The alkyl group represented by may be linear or branched. The alkyl group preferably has 1 to 10 carbon atoms. The alkyl group is preferably a methyl group, an ethyl group, an n-butyl group, or a t-butyl group.

[0067] Next, we will explain equation (ZaII). In equation (ZaII), R ２０４ and R ２０５Each 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 Preferably, the alkyl and cycloalkyl groups are 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).

[0068] R ２０４ and R ２０５ The aryl group, alkyl group, and cycloalkyl group may each independently have substituents. ２０４ and R ２０５ Examples of substituents that the aryl group, alkyl group, and cycloalkyl group may have include alkyl groups (e.g., C1-C15), cycloalkyl groups (e.g., C3-C15), aryl groups (e.g., C6-C15), alkoxy groups (e.g., C1-C15), halogen atoms, hydroxyl groups, and phenylthio groups.

[0069] Specific examples of organic cations are shown below, but the present invention is not limited thereto.

[0070]

[0071]

[0072] The molecular weight of the first acid generator is preferably 400 to 2000, more preferably 450 to 1750, and even more preferably 500 to 1500.

[0073] The first acid generator may be used alone or in combination of two or more types. The content of the first acid generator is preferably 1.0 to 60.0% by mass, more preferably 5.0 to 50.0% by mass, and even more preferably 10.0 to 40.0% by mass, relative to the total solid content of the resist composition, in terms of achieving superior effects of the present invention.

[0074] [Specific Resin] This resist composition contains a specific resin having repeating units represented by formula (P1).

[0075] <Repeating unit represented by formula (P1)>

[0076]

[0077] In formula (P1), Xa １ represents a hydrogen atom, an alkyl group, a cyano group, or a halogen atom, with a hydrogen atom or an alkyl group having 1 to 5 carbon atoms being preferred, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms being more preferred, and a hydrogen atom or a methyl group being even more preferred.

[0078] In formula (P1), T represents a single bond or a divalent linking group, and a single bond is preferred in that the effects of the present invention are superior. Examples of the divalent linking group include optionally substituted alkylene groups, optionally substituted aromatic ring groups, -COO-Rt- groups, and -O-Rt- groups. In the formula, Rt represents optionally substituted alkylene groups or optionally substituted cycloalkylene groups, with alkylene groups having 1 to 5 carbon atoms being preferred, and linear alkylene groups having 1 to 3 carbon atoms being more preferred. Examples of substituents that the aromatic ring groups, alkylene groups, and cycloalkylene groups may have include alkyl groups (preferably having 1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (preferably having 1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (preferably having 2 to 6 carbon atoms). The number of carbon atoms of the substituent is preferably 8 or less.

[0079] In formula (P1), Lx １ is a single bond or -CRx ４ Rx ５ Rx represents -O-, and a single bond is preferred. ４ and Rx５ Each of these independently represents a hydrogen atom or a monovalent organic group. The number of carbon atoms in the monovalent organic group is preferably 1 to 30, and more preferably 1 to 12. Examples of the monovalent organic group include optionally substituted alkyl groups, optionally substituted cycloalkyl groups, optionally substituted alkenyl groups, and optionally substituted aromatic ring groups, with optionally substituted alkyl groups being preferred. Examples of substituents that the alkyl groups, cycloalkyl groups, alkenyl groups, and aromatic ring groups may have include alkyl groups (preferably with 1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (preferably with 1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (preferably with 2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0080] In formula (P1), Rx １ ~Rx ３ Two of these groups are bonded together to form a monoring, and the remaining one represents an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group. The monoring can consist of one or more methylene groups that make up the ring, such as heteroatoms like -O- and -S-, as well as -CO-, -SO-, and -SO-. ３ Examples include monocyclic aliphatic hydrocarbon rings which may be substituted with at least one group selected from the group consisting of divalent groups including heteroatoms such as -. The monocyclic ring may have an unsaturated bond such as a vinylene group as part of the ring. The number of carbon atoms in the monocyclic ring is preferably 3 to 10, and more preferably 5 or 6. As the monocyclic ring, monocyclic cycloalkanes such as cyclobutane, cyclopentane, cyclohexane, and cyclooctane are preferred. １ ~Rx ３ The alkyl group represented by is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group. １ ~Rx ３The cycloalkyl group represented by Rx is preferably a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, as well as a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. １ ~Rx ３ The alkenyl group represented by is preferably an alkenyl group having 2 to 5 carbon atoms, such as a vinyl group. １ ~Rx ３ The alkynyl group represented by is preferably an alkynyl group having 2 to 5 carbon atoms, and more preferably an ethynyl group or a propargyl group. １ ~Rx ３ 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.

[0081] In the specified resin, the repeating unit represented by formula (P1) may be used alone or in combination of two or more types. The content of the repeating unit represented by formula (P1) is preferably 5.0 to 90.0 mol%, more preferably 10.0 to 85.0 mol%, and even more preferably 15.0 to 80.0 mol%, relative to the total repeating units of the specified resin, in terms of achieving superior effects of the present invention.

[0082] The specific resin may have repeating units other than those represented by formula (P1).

[0083] <Other Repeating Units> Below, we will describe in detail other repeating units that are different from the repeating unit represented by formula (P1) that a specific resin may have.

[0084] (Repeating units having acid-degradable groups) The specified resin may have repeating units having acid-degradable groups that are different from the repeating unit represented by formula (P1) (hereinafter also referred to as "repeating unit P2").

[0085] The acid-degradable group may be either a group that decomposes upon the action of an acid to increase its polarity or a group that decreases its polarity, but it is preferable that it is a group that decomposes upon the action of an acid to increase its polarity, and typically it is a group that decomposes upon the action of an acid to produce a polar group. The acid-degradable group preferably has a structure in which the polar group is protected by a group that is eliminated upon the action of an acid (leaving group). 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.

[0086] Examples of groups that are eliminated by the action of an acid on the repeating unit P2 include the group represented by any of the following formulas: (Y1), (Y2), and (Y3). Formula (Y1): -C(Rx １１ ) (Rx １２ ) (Rx １３ ) Formula (Y2): -C(R ３６ ) (Caution ３７ ) ( OR ３８ ) Formula (Y3): -C(Rn)(H)(Ar)

[0087] In formula (Y1), Rx １１ ~Rx １３ 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). １１ ~Rx １３ If all of them are alkyl groups (linear or branched), then Rx １１ ~Rx １３It is preferable that at least two of them are methyl groups. １１ ~Rx １３ Each preferably independently represents a linear or branched alkyl group, and Rx １１ ~Rx １３ It is more preferable that each of these independently represents a linear alkyl group. １１ ~Rx １３ These two may combine to form a polyring. Rx １１ ~Rx １３ Examples and preferred embodiments of alkyl groups, cycloalkyl groups, alkenyl groups, alkynyl groups, and aryl groups represented by Rx are as described above. １ ~Rx ３ This is the same as the alkyl group, cycloalkyl group, alkenyl group, alkynyl group, and aryl group represented by .

[0088] Rx １１ ~Rx １３ A polycyclic cycloalkyl group is preferred as the polycyclic ring formed by the bonding of these two. １１ ~Rx １３ The polycyclic cycloalkyl group formed by the bonding of these two groups is preferably a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. １１ ~Rx １３ The polycyclic cycloalkyl group formed by the bonding of these two groups may have one of the methylene groups constituting the ring substituted with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. In these polycyclic cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be substituted with vinylene groups. The group represented by formula (Y1) is, for example, Rx １１ is a methyl group or an ethyl group, and Rx １２ and Rx １３ A preferred embodiment is one in which the two are bonded together to form the aforementioned polycyclic cycloalkyl group.

[0089] When this resist composition is used as an EUV resist, Rx １１ ~Rx １３Alkyl groups, cycloalkyl groups, alkenyl groups, aryl groups, and Rx are represented by １１ ~Rx １３ The polycyclic ring formed by the bonding of these two elements may further preferably have a fluorine atom or an iodine atom as a substituent.

[0090] In formula (Y2), R ３６ ~R ３８ Each of these independently represents a hydrogen atom or a monovalent organic group. Examples of monovalent organic groups include alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, alkenyl groups, and alkynyl groups. ３６ It 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 substituted with groups containing heteroatoms such as oxygen atoms and / or carbonyl groups. ３７ and R ３８ These may be bonded to each other to form a ring (preferably polycyclic). 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 this resist composition 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.

[0091] 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 an alicyclic ring. An aryl group is preferred as Ar. When this resist composition 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.

[0092] From the standpoint of excellent acid decomposition properties, in the case of a leaving group that protects a polar group, if the polar group (or its residue) is directly bonded to an alicyclic ring, it is also preferable that the ring member atoms in the alicyclic 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.

[0093] The repeating unit P2 is preferably the repeating unit represented by formula (B1).

[0094]

[0095] In formula (B1), R ｂ１ and R ｂ２ Each of these independently represents a hydrogen atom or an alkyl group which may have substituents. ｂ１ and R ｂ２ Examples of alkyl groups that may have the above 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. ｂ１ A hydrogen atom is preferred as the component. ｂ２ Preferably, the group is a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0096] In formula (B1), L ｂ１ This represents a single bond or a -COO-.

[0097] In formula (B1), Ar ｂ１ represents an s+t+1 valent aromatic ring group. The above aromatic ring group may be monocyclic or polycyclic. The above aromatic ring group may be either an aromatic hydrocarbon group or an aromatic heterocyclic group, with aromatic hydrocarbon groups being preferred. As the above aromatic hydrocarbon group, for example, groups containing aromatic hydrocarbon rings having 6 to 18 carbon atoms, such as benzene, naphthalene, anthracene, and naphthacene, are preferred. As the heteroatoms of the above aromatic heterocyclic group, nitrogen atoms, oxygen atoms, or sulfur atoms are preferred. As the aromatic heterocyclic group, for example, 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, are preferred. The number of ring member atoms of the above aromatic ring group is preferably 6 to 18, and more preferably 6 to 10.

[0098] In formula (B1), Y ｂ１ is, -OR ｂ or -COOR ｂ Represents R ｂ This represents the base expressed by the above-mentioned equations (Y1) to (Y3). If s is an integer greater than or equal to 2, there are multiple Y ｂ１ They may be the same or different from one another.

[0099] In formula (B1), R ｂ３ is, -OR ｂ and -COOR ｂ Represents a different substituent. ｂ３ It is also preferable that the group does not contain an acid-degradable group. ｂ３ Examples of groups represented by include halogen atoms, alkyl groups, cycloalkyl groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, aryl groups, heteroaryl groups, carboxyl groups, and groups formed by combining two or more of these. When t is an integer of 2 or more, there are multiple R groups. ｂ３They may be the same or different from one another.

[0100] In formula (B1), s represents an integer of 1 or more, preferably an integer between 1 and 4, and more preferably 1 or 2. t represents an integer of 0 or more, preferably an integer between 0 and 4, and more preferably an integer between 0 and 2.

[0101] In formula (B1), R ｂ１ and Ar ｂ１ They may be linked to each other via single bonds or divalent linking groups to form a ring. When t represents an integer of 1 or more, R ｂ１ and R ｂ３ They may be linked to each other via single bonds or divalent linking groups to form a ring. When s represents an integer of 2 or more, Y ｂ１ They may be linked to each other via single bonds or divalent linking groups to form a ring, and when t represents an integer of 2 or more, R ｂ３ These elements may be bonded to each other via single bonds or divalent linking groups to form a ring. Examples of the divalent 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.

[0102] As the repeating unit P2, the repeating unit represented by formula (A) is also preferred.

[0103]

[0104] In formula (A), 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 ２At 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 １ The 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.

[0105] In formula (A), 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.

[0106] In formula (A), R ２ Examples of leaving groups that may have a fluorine atom or an iodine atom, represented by formulas (Y1) to (Y3) above, include leaving groups that have a fluorine atom or an iodine atom.

[0107] As the repeating unit P2, the repeating unit represented by formula (AI) is also preferred.

[0108]

[0109] In formula (AI), Xa １１ represents a hydrogen atom or an optionally substituted alkyl group. Examples of optionally substituted alkyl groups 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 The definition and preferred embodiment of R in formula (B1) １１ It is the same as Xa １ Preferably, the group is a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0110] In formula (AI), T represents a single bond or a divalent linking group. The definition and preferred embodiment of T in formula (AI) are the same as those of T in formula (P1). Rx １１ ~Rx １３ The definition and preferred embodiment of Rx in formula (Y1) １１ ~Rx １３ It is the same as this.

[0111] The repeating unit represented by formula (AI) is an acid-degradable (meth)acrylate tertiary alkyl ester repeating unit (Xa １１ A repeating unit in which represents a hydrogen atom or a methyl group, and T represents a single bond, is preferred.

[0112] The repeating unit P2 may have an acid-degradable group containing an unsaturated bond. The repeating unit P2 having an acid-degradable group containing an unsaturated bond is preferably the repeating unit represented by formula (B).

[0113]

[0114] In formula (B), Xb represents a hydrogen atom, a halogen atom, or an optionally substituted alkyl group. Examples of optionally substituted alkyl groups include a methyl group or -CH２ -R １１ Examples of groups represented by are R in formula (B). １１ The definition and preferred embodiment of R in formula (B1) １１ It is the same as above. For Xb, a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group is preferred.

[0115] In formula (B), L represents a single bond or a divalent linking group which may have a substituent. The divalent linking group represented by L is -Rt ｂ -, -CO-, -COO-Rt ｂ -, -COO-Rt ｂ -CO-, -Rt ｂ -CO- and -O-Rt ｂ - can be cited. Rt ｂ Rt represents an alkylene group, a cycloalkylene group, or an aromatic ring group, with an aromatic ring group being preferred. ｂ It may have substituents such as halogen atoms, hydroxyl groups, or alkoxy groups. As L, -Rt ｂ - group, -CO- group, -COO-Rt ｂ -CO- group, or -Rt ｂ -CO- groups are preferred.

[0116] In formula (B), Ry １ ~Ry ３ Each of these independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, or an aryl group. However, Ry １ ~Ry ３ At least one of these represents an alkenyl group, an alkynyl group, a cycloalkenyl group, or an aryl group. １ ~Ry ３ Examples and preferred embodiments of alkyl groups, cycloalkyl groups, alkenyl groups, alkynyl groups, and aryl groups represented by Rx are as described above. １１ ~Rx １３ This is the same as the alkyl group, cycloalkyl group, alkenyl group, alkynyl group, and aryl group represented by Ry. １ ~Ry ３The cycloalkenyl group represented by is preferably a structure in which a double bond is included in part of a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group.

[0117] Ry １ ~Ry ３ These two may combine to form a polyring. １ ~Ry ３ The polycyclic cycloalkyl group formed by the bonding of these two groups is preferably a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. １ ~Ry ３ A polycyclic cycloalkyl group or polycyclic 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 - The group may be substituted with a group containing a heteroatom such as a - group, or a combination thereof. 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 configuration is one in which the two are bonded together to form the aforementioned polycyclic cycloalkyl group or polycyclic cycloalkenyl group.

[0118] 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.

[0119] The repeating units represented by formula (B) are preferably acid-degradable (meth)acrylic acid tertiary ester repeating units (where Xb represents a hydrogen atom or a methyl group, and L represents a -CO- group), acid-degradable hydroxystyrene tertiary alkyl ether repeating units (where 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 (where Xb represents a hydrogen atom or a methyl group, and L represents -Rt ｂ -CO- group (Rt ｂ (This is a repeating unit representing an aromatic ring group.)

[0120] 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.

[0121] Specific examples of repeating units P2 are shown below, but are not limited to these. Furthermore, as examples of repeating units P2, one can also refer to the descriptions in

[0029] to

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

[0122]

[0123] The repeating unit P2 may be used alone or in combination of two or more types. The content of the repeating unit P2 is preferably 5.0 to 90.0 mol%, more preferably 7.5 to 85.0 mol%, and even more preferably 10.0 to 80.0 mol%, relative to the total repeating units in the acid-degradable resin.

[0124] (Repeating units having acidic groups) The specific resin may also preferably contain repeating units having acidic groups. The repeating units having acidic groups are preferably different from the repeating units represented by the above formula (P1) and repeating unit P2. Furthermore, the repeating units having acidic groups may have fluorine atoms or iodine atoms. Preferred acidic groups are carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), sulfonic acid groups, sulfonamide groups, or isopropanol groups, with phenolic hydroxyl groups being more preferred. In other words, the specific resin may preferably contain repeating units having phenolic hydroxyl groups. In the above hexafluoroisopropanol group, one or more fluorine atoms (preferably 1 to 2) may be substituted with groups other than fluorine atoms (such as alkoxycarbonyl groups). As for the acidic groups, 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.

[0125] As for the repeating unit having an acid group, the repeating unit represented by the following formula (Pa1) is preferred.

[0126]

[0127] In formula (Pa1), R ａ１ and R ａ２ Each of these independently represents a hydrogen atom or a substituent. ａ１ and R ａ２ The substituents represented are not particularly limited, but alkyl groups, cycloalkyl groups, halogen atoms, cyano groups, or alkoxycarbonyl groups are preferred. ａ１ and R ａ２The 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 R 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 and a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. The cycloalkyl group may also have substituents. ａ１ and R ａ２ Examples of halogen atoms represented by include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms 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.

[0128] 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. ａ３Examples of alkyl groups when represents 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.

[0129] 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.

[0130] 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.

[0131] In the above formula (Pa1), R Ｘ R represents substituents other than hydroxyl groups. Ｘ Examples of substituents represented by include carboxyl groups, sulfonic acid groups, cyano groups, halogen atoms, hydrocarbon groups, amino groups, nitro groups, and groups formed by combining two or more of these. ＸExamples 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 If the hydrocarbon group represented by contains a methylene group, then at least one of the methylene groups 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.

[0132] In the above formula (Pa1), n ​​represents an integer from 1 to 9, preferably an integer from 1 to 5, and more preferably an integer from 1 to 4. m represents an integer from 0 to 8, preferably an integer from 0 to 4, and more preferably an integer from 0 to 3.

[0133] As a repeating unit having an acidic group, a repeating unit represented by the following formula (Pa2) is also preferred.

[0134]

[0135] 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 group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and t-butyl group.

[0136] In the above formula (Pa2), L ａ２represents a single bond or -COO-, with a single bond being preferred. r represents an integer from 0 to 3, preferably an integer from 0 to 2, more preferably 0 or 1, and even more preferably 0. In formula (Pa2), the aromatic ring is 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 from 1 to 5, preferably an integer from 1 to 4. m1 represents an integer from 0 to 4, preferably an integer from 0 to 3.

[0137] 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, with fluorine or iodine being more preferred. 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 When the hydrocarbon group represented by contains a methylene group, at least one of the methylene groups 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.

[0138] Specific examples of repeating units having an acid group include, for example, the repeating units described in

[0079] to

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

[0139] The repeating units having acidic groups may be used alone or in combination of two or more types. The content of the repeating units having acidic groups is preferably 5 to 90 mol%, more preferably 10 to 90 mol%, and even more preferably 20 to 80 mol%, relative to the total repeating units of the specific resin.

[0140] (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) The specified resin may 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 unit Y and repeating unit PA, which will be described later. The repeating unit X is preferably a repeating unit represented by formula (C).

[0141]

[0142] In formula (C), L ５ R represents a single bond or a -COO- bond. ９ R represents an alkyl group which may have a hydrogen atom, or a fluorine atom or an iodine atom. １０ This 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.

[0143] The content of repeating unit X is preferably 0 to 40 mol%, more preferably 5 to 35 mol%, and even more preferably 10 to 35 mol%, relative to the total repeating units in the specific resin.

[0144] Furthermore, the specific 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 acidic group, and repeating units having a fluorine atom, a bromine atom, or an iodine atom. Specific examples of repeating units having a fluorine atom or an iodine atom include, for example, the repeating units described in

[0116] to

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

[0145] The total content of repeating units in the specified resin that contain at least one of fluorine atoms, bromine atoms, and iodine atoms 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 specified resin. There is no particular upper limit, but for example, it is 100 mol% or less relative to the total repeating units of the specified resin.

[0146] (Repeating units having lactone groups, sultone groups, or carbonate groups) The specific resin 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.

[0147] 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. Among these, a 5-7 membered ring lactone structure in which another ring structure is fused to form a bicyclo or spiro structure, or a 5-7 membered ring sultone structure in which another ring structure is fused to form a bicyclo or spiro structure, is more preferred. For units containing a lactone group or sultone group, refer, for example, to the descriptions in

[0119] to

[0126] and

[0132] to

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

[0148] 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.

[0149] When the specific resin contains repeating units Y, the content of repeating units Y is preferably 1 to 80 mol%, and more preferably 10 to 60 mol% or more, relative to the total number of repeating units in the specific resin.

[0150] (Repeating units having photoacid generating groups) The specific resin may contain repeating units (hereinafter also referred to as "repeating unit PA") that have a group that generates acid upon irradiation with active light or radiation (also called a "photoacid generating group"), but it is also preferable that it does not contain repeating unit PA. An example of a repeating unit PA is the repeating unit represented by formula (4).

[0151]

[0152] In formula (4), R ４１ L represents a hydrogen atom or a methyl group. ４１ represents a single bond or a divalent linking group, and a single bond or -COO- is preferred. ４２ The symbols represent divalent linking groups, including alkylene groups, cycloalkylene groups, arylene groups, -O-, -CO-, -S-, -SO-, and -SO ２ A linking group consisting of at least one selected from the group consisting of - and -NR- is preferred. 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 monocyclic or polycyclic. 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.

[0153] In formula (4), R ４０ The group represents a structural site that decomposes upon irradiation with active light or radiation, generating acid in the side chain, and a group represented by the following formula (S4-1) is preferred.

[0154]

[0155] In equation (S4-1), Q － represents an acid residue, M ＋ * represents a cation. * represents L ４１This 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. ＋ Examples of cations represented by this expression include cations that may be contained in the first acid generator described above.

[0156] Specific examples of repeating units PA 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.

[0157] When the specific resin contains repeating units PA, the content of repeating units PA is preferably 1 to 40 mol%, more preferably 3 to 30 mol%, and even more preferably 5 to 30 mol%, relative to the total repeating units in the specific resin.

[0158] (Repeating units represented by formula (V-1) or formula (V-2)) The specified resin 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.

[0159]

[0160] 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 or fluorinated alkyl group having 1 to 6 carbon atoms), or a carboxyl group. As the alkyl group, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms are 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.

[0161] (Repeating units to reduce the mobility of the main chain) A specific resin is preferable to have a high glass transition temperature (Tg) in order to suppress excessive diffusion of generated acid or pattern collapse during development. The specific resin may have repeating units to reduce the mobility of the main chain in order to adjust the glass transition temperature. 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.

[0162] (Repeating units having at least one group selected from lactone groups, sultone groups, carbonate groups, hydroxyl groups, cyano groups, and alkali-soluble groups) The specific resin 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 include the repeating units described in the description of repeating unit Y above. The preferred content is also as described in the description of repeating unit Y.

[0163] The specific 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 saturated hydrocarbon groups (substituted with a hydroxyl group or a cyano group) that have 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 acid-degradable groups. 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.

[0164] The specific resin may have repeating units having alkali-soluble groups. The inclusion of repeating units having alkali-soluble groups in the specific resin increases 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.

[0165] (Repeating units having an alicyclic hydrocarbon structure and not exhibiting acid decomposition) The specific resin 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.

[0166] (Repeating Unit Represented by Formula (III) Having Neither a Hydroxy Group nor a Cyano Group) The specific resin may have a repeating unit represented by Formula (III) that has neither a hydroxy group nor a cyano group.

[0167]

[0168] In Formula (III), R ５ represents a hydrocarbon group that has at least one ring structure and has neither a hydroxy group nor a cyano group. Ra represents a hydrogen atom, an alkyl group, or -CH ２ -O-Ra ２ group. In the formula, Ra ２ represents a hydrogen atom, an alkyl group, or an acyl group. Examples of the repeating unit represented by Formula (III) that has neither a hydroxy group nor a cyano group include the repeating units described in paragraphs

[0087] to

[0094] of Japanese Patent Application Laid-Open No. 2014-098921, the description of which is incorporated herein by reference.

[0169] The specific resin may have other repeating units besides the repeating units described above. For the other repeating units, reference can be made to, for example, the descriptions of

[0141] to

[0143] and

[0169] to

[0170] of International Publication No. WO 2022 / 024928, the description of which is incorporated herein by reference. The specific resin may contain various repeating units other than the above repeating units for the purpose of adjusting dry etching resistance, suitability for standard developers, substrate adhesion, resist profile, resolution, heat resistance, sensitivity, and the like.

[0170] A preferred embodiment of the present invention is that the specific resin has at least one selected from the group consisting of a lactone group, a carbonate group, a sultone group, and a saturated hydrocarbon group having a hydroxy group. When the specific resin has at least one selected from the group consisting of a lactone group, a carbonate group, a sultone group, and a saturated hydrocarbon group having a hydroxy group, etching resistance and LWR performance are further improved.

[0171] A preferred embodiment of the present invention is that the specific resin contains a repeating unit having an iodine atom. When the specific resin contains a repeating unit having an iodine atom, the absorptivity for EUV light or the like increases, the influence of shot noise can be reduced, and LWR performance is further improved.

[0172] The specific resin can be synthesized according to a conventional method (for example, radical polymerization). The weight average molecular weight (Mw) of the specific resin is preferably from 1,000 to 200,000, more preferably from 3,000 to 50,000, and still more preferably from 5,000 to 20,000. The polydispersity (molecular weight distribution, Mw / Mn) of the specific resin is preferably from 1 to 5, more preferably from 1 to 4, and still more preferably from 1 to 3. The smaller the polydispersity is, the more excellent the resolution and the resist shape are; further, the side wall of the resist pattern is smoother, and the roughness property is also more excellent.

[0173] The specific resin may be used singly or in combination of two or more kinds thereof. The content of the specific resin is preferably 40.0 to 99.9% by mass, more preferably 42.5 to 95.0% by mass, and still more preferably 45.0 to 90.0% by mass, based on the total solid content of the resist composition.

[0174] [Specific Compound] The resist composition contains at least one specific compound selected from the group consisting of: a second acid generator that generates a second acid having a pKa of -0.75 or more by the action of an actinic ray or radiation; and a second compound that generates a compound different from the above-mentioned first acid by the action of an actinic ray or radiation, wherein the generated compound contains a nitrogen atom bonded to three atoms selected from a carbon atom and a hydrogen atom (hereinafter also referred to as "specific nitrogen atom") and a sulfonic acid group.

[0175] The pKa of the second acid is -0.75 or higher, preferably -0.70 or higher, and more preferably -0.65 or higher. There is no particular upper limit to the pKa of the second acid, but it is preferably 10.00 or lower, more preferably 8.00 or lower, and even more preferably 6.00 or lower. The difference between the pKa of the second acid and the pKa of the first acid (value of pKa of second acid - pKa of first acid) is preferably 0.50 or higher, more preferably 0.75 or higher, and even more preferably 1.00 or higher. There is no particular upper limit to the difference between the pKa of the second acid and the first acid, but it is often 10.00 or lower, and preferably 8.00 or lower. If the second acid has multiple pKa values, the above pKa of the second acid refers to the highest pKa. That is, if the second acid has multiple pKa values, it is sufficient that the highest pKa is within the above range, and it is preferable that all pKa values ​​are within the above range. If multiple first acids exist, the pKa of the first acid in the difference between the pKa of the second acid and the pKa of the first acid refers to the lowest pKa among the multiple first acids. Furthermore, if the first acid has multiple pKas, the pKa of the first acid in the difference between the pKa of the second acid and the pKa of the first acid refers to the lowest pKa.

[0176] As the second acid, an organic acid is preferred. 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 acids, bis(alkylsulfonyl)imide acids, and tris(alkylsulfonyl)methidic acids, with sulfonic acids or carboxylic acids being preferred. The above organic acids are also preferably free of aromatic rings. The above organic acids are also preferably aliphatic acids.

[0177] The second acid generator is not particularly limited as long as it is a compound that generates a second acid by the action of active light or radiation, but it is preferably an onium salt. Examples of the onium salt include an onium salt containing an anion, which is formed by removing the hydrogen atom from the acid group of the second acid, and a cation. The cation is not particularly limited and includes cations that the first acid generator described above may have, with sulfonium cations or iodonium cations being preferred. That is, the second acid generator preferably contains a sulfonium cation or an iodonium cation. Among the second acid generators, compounds represented by formulas (D2) to (D5) described later are preferred, and compounds represented by formulas (D2) or (D3) described later are more preferred.

[0178] The compound from which the second compound is generated has a specific nitrogen atom and a sulfonic acid group, and is a different compound from the first acid described above. In other words, the second compound is a different compound from the first acid generator described above. The pKa of the compound from which the second compound is generated is not particularly limited, but is preferably -5.00 to 2.00, more preferably -4.50 to 1.50, and even more preferably -4.00 to 1.00. The pKa of the sulfonic acid group of the compound from which the second compound is generated may be lower than the pKa of the first acid.

[0179] The compound from which the second compound is generated is preferably an aliphatic sulfonic acid. The compound from which the second compound is generated is also preferably free of aromatic rings.

[0180] The compound from which the second compound is generated has a specific nitrogen atom bonded to three atoms selected from carbon atoms and hydrogen atoms. More specifically, the specific nitrogen atom is bonded to one carbon atom and two atoms selected from carbon atoms and hydrogen atoms. For example, nitrogen atoms constituting cyano groups, nitro groups, and sulfonamide groups are not included in the specific nitrogen atom. The carbon atom bonded to the specific nitrogen atom may be a carbonyl carbon, etc. It is also preferable that the specific nitrogen atom is a nitrogen atom having 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.

[0181]

[0182] The second compound is not particularly limited as long as it contains a specific nitrogen atom and a sulfonic acid group and generates a compound different from the first acid, but it is preferably an onium salt containing a sulfonic acid anion containing a specific nitrogen atom and a cation. The above cation is not particularly limited and includes cations that the first acid generator described above may have, with sulfonium cations or iodonium cations being preferred, and sulfonium cations being more preferred. In other words, the second compound preferably contains a sulfonium cation or an iodonium cation. Among the second compounds, the compound represented by formula (D1) described later is preferred.

[0183] The specific compound preferably includes a compound represented by any of formulas (D1) to (D5), and more preferably includes a compound represented by any of formulas (D1) to (D3), in that the effects of the present invention are superior.

[0184]

[0185] In formulas (D1) to (D5), M ｆ＋ represents an f-valent cation. Examples of f-valent cations include cations that may be present in the first acid generator described above, with sulfonium cations or iodonium cations being preferred. f represents an integer of 1 or more, preferably an integer between 1 and 3, more preferably 1 or 2, and even more preferably 1. a represents an integer of 1 or more, preferably an integer between 1 and 3, more preferably 1 or 2, and even more preferably 1. b represents an integer of 1 or more, preferably an integer between 1 and 3, more preferably 1 or 2, and even more preferably 1. c represents an integer of 1 or more, preferably an integer between 1 and 3, more preferably 1 or 2, and even more preferably 1. However, a, b, c, and f satisfy the relationship a × b = c × f.

[0186] In formula (D1), R Ｎ１This represents an α-valent organic group containing a specific nitrogen atom. The number of carbon atoms in the above α-valent organic group is preferably 3 to 30, more preferably 5 to 28, and even more preferably 5 to 25. The above α-valent organic group containing a specific nitrogen atom contains a specific nitrogen atom, and one or more methylene groups are -O-, -CO-, -S-, -SO-, and -SO ２ Examples of α-valent hydrocarbon groups include those which may be replaced by a group selected from the group consisting of , and which may have substituents. Examples of substituents include halogen atoms (preferably fluorine atoms), hydroxyl groups, and cyano groups. The α-valent hydrocarbon group may contain an aromatic ring, but it is preferable that it does not contain an aromatic ring in order to obtain better effects of the present invention. That is, R Ｎ１ It is preferable that this is an α-valent aliphatic group containing a specific nitrogen atom.

[0187] R Ｎ１ The number of nitrogen atoms contained is 1 or more, preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. Ｎ１ It is also preferable that the specific nitrogen atom possessed is bonded to a leaving group that is removed by the action of an acid or light. Examples of the above leaving group include known protecting groups of amines (for example, a group that is removed by the action of an acid, such as the Boc(t-butoxycarbonyl) group (hereinafter also referred to as an "acid leaving group"); a group that is removed by the action of light, such as the 4-nitrobenzyloxycarbonyl group (hereinafter also referred to as a "photoleaving group"). An example of the above acid leaving group is a group represented by formula (N).

[0188]

[0189] In formula (N), R １ , R ２ , and R ３ Each of these independently represents an organic group. １ ~R ３The organic group represented is preferably an alkyl group, a cycloalkyl group, an alkenyl group, or an aryl group. The number of carbon atoms in the alkyl group is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 3. The number of carbon atoms in the alkenyl group is preferably 2 to 10, more preferably 2 to 5, and even more preferably 2 or 3. The number of carbon atoms in the cycloalkyl group is preferably 6 to 15, and more preferably 6 to 10. The aryl group is preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group, a naphthyl group, and anthryl group. １ ~R ３ The organic group represented is preferably an alkyl group, and more preferably a linear alkyl group. １ , R ２ , and R ３ Two of these may bond to each other to form a ring. The ring may be monocyclic or polycyclic. Cycloalkanes are preferred as the ring, and monocyclic cycloalkanes with 5 to 6 members are more preferred. The dashed lines indicate the bond position with the nitrogen atom.

[0190] R Ｎ１ The ring may contain a specific nitrogen atom as a ring member atom. The ring may also have heteroatoms other than nitrogen atoms, such as oxygen atoms and sulfur atoms, as ring member atoms. The number of heteroatoms contained in the ring is 1 or more, preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. However, the ring member atom adjacent to the specific nitrogen atom is a carbon atom. The ring may be either an alicyclic or an aromatic ring, with alicyclic being preferred. The ring may be either a monocyclic or polycyclic ring. The number of ring member atoms in the ring is preferably 5 to 20, more preferably 5 to 15, even more preferably 6 to 10, and especially preferably 6.

[0191] The compound represented by formula (D1) is preferably a compound represented by the group represented by formula (D1-1) or the group represented by formula (D1-2).

[0192]

[0193] In equations (D1-1) and (D1-2), R Ｎ２ and R Ｎ３Each of these independently represents a monovalent organic group. Examples of the above monovalent organic groups include alkyl groups (preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms), cycloalkyl groups (preferably having 3 to 15 carbon atoms, more preferably 6 to 10 carbon atoms), alkenyl groups (preferably having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms), monovalent heterocyclic groups (preferably 5 to 10-membered rings, more preferably 5 to 7-membered rings, even more preferably 5 to 6-membered rings), monovalent aromatic ring groups (preferably 6 to 10-membered rings, more preferably 6-membered rings; for example, a benzene ring group), and leaving groups that are eliminated by the action of the above-mentioned acid or light, with alkyl groups, cycloalkyl groups, or leaving groups that are eliminated by the action of acid or light being preferred. Each of the groups exemplified above as monovalent organic groups may have substituents. Examples of substituents include alkyl groups (preferably having 1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (preferably having 1 to 4 carbon atoms), carboxyl groups, alkoxycarbonyl groups, and alkylsulfonyl groups. Ｎ２ These elements may be bonded to each other to form a ring which may have substituents. The details and preferred embodiments of the above ring are the same as those described above for the ring containing a nitrogen atom as a ring member atom. Examples of substituents that the above ring may have include alkyl groups (preferably having 1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (preferably having 1 to 4 carbon atoms), carboxyl groups, alkoxycarbonyl groups, and alkylsulfonyl groups.

[0194] In formula (D1-2), C Ｎ This represents a ring containing a nitrogen atom as a ring member atom. Details and preferred embodiments of the ring containing a nitrogen atom as a ring member atom are as described above.

[0195] In equations (D1-1) and (D1-2), L ｄ１ and L ｄ２ These each independently represent a divalent linking group. Examples of divalent linking groups are -CO- and -NR Ｎ -, -O-, -S-, -SO-, -SO ２- Examples include optionally substituted alkylene groups, optionally substituted cycloalkylene groups, optionally substituted alkenylene groups, optionally substituted divalent aliphatic heterocyclic groups, and groups formed by combinations thereof. Ｎ represents a hydrogen atom or a monovalent organic group, preferably a hydrogen atom or an alkyl group (preferably having 1 to 6 carbon atoms). Examples of substituents that the alkylene group, cycloalkylene group, alkenylene group, and divalent aliphatic heterocyclic group may have include halogen atoms (preferably fluorine atoms), alkylsulfonyl groups, and cyano groups. ｄ１ and L ｄ２ Preferably, the linking group is a divalent linking group having at least one selected from the group consisting of a fluorine atom, an alkylsulfonyl group, a cyano group, -CO-, and -COO-, and more preferably an alkylene group having a fluorine atom or an alkylsulfonyl group.

[0196] In equations (D1-1) and (D1-2), X ｄ１ and X ｄ２ Each of these independently represents a linked group with a+1 valency. However, X ｄ１ and X ｄ２ In formulas (D1-1) and (D1-2), the nitrogen atom and the atom adjacent to it are carbon atoms. The above a+1 valent linking group consists of one or more methylene groups that are -O-, -CO-, -S-, -SO-, and -SO ２ Examples include a+1 valent hydrocarbon groups, which may be replaced by a group selected from the group consisting of - and may have substituents. Examples of the above hydrocarbon groups include aliphatic hydrocarbon groups and aromatic hydrocarbons, with aliphatic hydrocarbon groups being preferred. The number of carbon atoms in the above a+1 valent hydrocarbon group is preferably 1 to 12, and more preferably 1 to 6. ｄ１ and X ｄ２ Preferably, the a+1 valent aliphatic hydrocarbon group is one in which one or more methylene groups may be substituted with either -O- or -CO-.

[0197] In formula (D2), R ｄ１This represents an α-valent organic group that does not contain a specific nitrogen atom. The number of carbon atoms in an α-valent organic group that does not contain a specific nitrogen atom is preferably 1 to 30, more preferably 3 to 28, and even more preferably 5 to 25. Examples of an α-valent organic group that does not contain a specific nitrogen atom include one or more methylene groups that are -O-, -CO-, -S-, -SO-, and -SO ２ Examples of α-valent hydrocarbon groups include those which may be replaced by a group selected from the group consisting of - and which may have substituents that do not contain a specific nitrogen atom. Examples of substituents that do not contain a specific nitrogen atom include halogen atoms (preferably fluorine atoms or iodine atoms), cyano groups, and hydroxyl groups. The above α-valent hydrocarbon group may contain an aromatic ring, but it is preferable that it does not contain an aromatic ring in terms of superior effects of the present invention. That is, R ｄ１ It is preferable that the aliphatic group is α-valent and does not contain a specific nitrogen atom.

[0198] In formulas (D3) to (D5), R ｄ２ , R ｄ３ , and R ｄ５ Each of these independently represents an α-valent organic group. The number of carbon atoms in the α-valent organic group is preferably 1 to 30, more preferably 3 to 28, and even more preferably 5 to 25. The α-valent organic group may, for example, contain a nitrogen atom, and one or more methylene groups may be -O-, -CO-, -S-, -SO-, and -SO ２ Examples of α-valent hydrocarbon groups include those which may be replaced by a group selected from the group consisting of , and which may have substituents. Examples of substituents include halogen atoms (preferably fluorine atoms or iodine atoms), cyano groups, and hydroxyl groups. The α-valent hydrocarbon group may contain an aromatic ring, but it is preferable that it does not contain an aromatic ring in order to obtain better effects of the present invention. That is, R ｄ２ , R ｄ３ , and R ｄ５ It is preferable that it is an aliphatic group with a valency.

[0199] In formulas (D3) to (D5), R ｄ４ , R ｄ６ , and R ｄ７each independently represent a monovalent organic group. The number of carbon atoms in the monovalent organic group is preferably 1 to 30, more preferably 1 to 25, and still more preferably 1 to 20. The monovalent organic group may, for example, contain a nitrogen atom, and one or more methylene groups may be replaced by -O-, -CO-, -S-, -SO-, and -SO ２ -, and examples thereof include a monovalent hydrocarbon group which may be substituted with a group selected from the group consisting of the above and may have a substituent. Examples of the substituent include a halogen atom (preferably a fluorine atom or an iodine atom), a cyano group, and a hydroxy group. The monovalent hydrocarbon group may contain an aromatic ring, but it is preferable that it does not contain an aromatic ring from the viewpoint that the effect of the present invention is more excellent. That is, R ｄ４ , R ｄ６ , and R ｄ７ are preferably monovalent aliphatic groups.

[0200] R ｄ３ and a pieces of R ｄ４ two or more selected from these may be bonded to each other to form an optionally substituted ring, and R ｄ５ , a pieces of R ｄ６ , and a pieces of R ｄ７ two or more selected from these may be bonded to each other to form an optionally substituted ring. The ring may be either monocyclic or polycyclic. The ring may be either an aromatic ring or an alicyclic ring, and an alicyclic ring is preferable. The number of ring atoms of the ring is preferably 5 to 20, more preferably 5 to 12. Examples of the substituent that the ring may have include an alkyl group (preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms), a cycloalkyl group (preferably having 3 to 15 carbon atoms, more preferably 6 to 10 carbon atoms), an alkylene group (preferably having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms), a monovalent heterocyclic group (preferably a 5- to 10-membered ring, more preferably a 5- to 7-membered ring, still more preferably a 5- to 6-membered ring), a monovalent aromatic ring group (preferably a 6- to 10-membered ring, more preferably a 6-membered ring), a halogen atom (preferably a fluorine atom or an iodine atom), a cyano group, and a hydroxy group. Each of the above groups may further have the substituents described above.

[0201] In equation (D4), Y ｄ１ and Y ｄ２ These are, independently, a single bond, -CO-, -SO-, or -SO ２ It represents -. However, Y ｄ１ and Y ｄ２ At least one of them is -CO-, -SO-, or -SO ２ It represents -.

[0202] The molecular weight of the specific compound is preferably 100 to 2000, more preferably 200 to 1750, and even more preferably 250 to 1500.

[0203] The specific compound may be used alone or in combination of two or more. The content of the specific compound is preferably 0.1 to 10% by mass, more preferably 0.2 to 8.0% by mass, and even more preferably 0.3 to 6.0% by mass, relative to the total solid content of the resist composition.

[0204] [Other Photoacid Generators] This resist composition may also contain a photoacid generator (hereinafter referred to as "third acid generator") that generates acid by the action of active light or radiation, which is different from the first acid generator and the specific compound. The pKa of the acid generated from the third acid generator is less than -0.75, preferably -0.80 or less, more preferably -1.50 or less, and even more preferably -1.70 or less. The lower limit of the pKa of the acid generated from the third acid generator is not particularly limited, but is preferably -5.00 or more, more preferably -4.50 or more, and even more preferably -4.00 or more.

[0205] The third acid generator may be in the form of a low molecular weight compound, or it may be incorporated into a polymer (for example, the specific resin described above). Alternatively, both the low molecular weight compound form and the form incorporated into a polymer (for example, the specific resin described above) may be used in combination. When the third acid generator is in the form of a low molecular weight compound, its molecular weight is preferably 3000 or less, more preferably 2000 or less, and even more preferably 1000 or less. There is no particular lower limit, but 100 or more is preferred. When the third acid generator is incorporated into a polymer, it may be incorporated into a specific resin, or into a resin different from the specific resin. In this specification, the third acid generator is preferably in the form of a low molecular weight compound.

[0206] Examples of third acid generators include onium salts containing anions and cations, and are preferably 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 acids, bis(alkylsulfonyl)imide acids, and tris(alkylsulfonyl)methidic acids. It is also preferable that the organic acids generated by the third acid generator do not contain specific nitrogen atoms.

[0207] Organic cations are preferred as the cations contained in the third acid generator. The valency of the cation may be monovalent or divalent or higher. Examples of the above cations include cations that may be present in the first acid generator described above, and sulfonium cations or iodonium cations are preferred. The cations may be used individually or in combination of two or more.

[0208] The anion contained in the third acid generator is preferably an organic anion. The valency of the anion may be monovalent or divalent or higher. The anion is preferably one with a remarkably low ability to undergo nucleophilic reactions, and more preferably a non-nucleophilic anion. The anion may be used alone or in combination of two or more types.

[0209] 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.

[0210] Examples of third acid generators that can be used include the photoacid generators disclosed in paragraphs

[0135] to

[0171] of International Publication No. 2018 / 193954, paragraphs

[0077] to

[0116] of International Publication No. 2020 / 066824, paragraphs

[0018] to

[0075] and

[0334] to

[0335] of International Publication No. 2017 / 154345, and the compounds exemplified in paragraphs

[0023] to

[0078] of International Publication No. 2020 / 158313. These contents are incorporated herein by reference.

[0211] The third acid generator may be used alone or in combination of two or more types. The content of the third acid generator is preferably 0.1 to 20.0% by mass, more preferably 0.2 to 17.5% by mass, and even more preferably 0.3 to 15.0% by mass, based on the total solid content of the resist composition.

[0212] [Hydrophobic Resin] This resist composition may contain a hydrophobic resin different from the specific resin described above. The hydrophobic resin is preferably designed to be unevenly distributed on the surface of the resist film formed by this resist composition, 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. Effects of adding a hydrophobic resin include control of the static and dynamic contact angles of the resist film surface with respect to water, and suppression of outgassing.

[0213] 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. ３It is preferable that the hydrophobic resin has one or more of the substructures, and more preferably two or more. 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 chains. Examples of hydrophobic resins include the compounds described in paragraphs

[0275] to

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

[0214] The hydrophobic resin may be used alone or in combination of two or more types. 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 15.0% by mass, and even more preferably 0.1 to 10.0% by mass, relative to the total solid content of the resist composition.

[0215] [Other Components] This resist composition may contain other components besides those described above.

[0216] <Surfactants> This resist composition 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.

[0217] The surfactant may be used alone or in combination of two or more types. When 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 0.01 to 1.0% by mass, relative to the total solid content of the resist composition.

[0218] <Solvent> This resist composition may contain 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. A bio-derived solvent may be used as the solvent. As bio-derived solvents, for example, those described in Japanese Patent Application Publication No. 2002-363135, U.S. Patent Application Publication No. 2015 / 0004664A1, and International Publication No. 2025 / 106697, as well as commercially available products such as the PURASOLV® ELECT series, can be used. The above bio-derived solvents may be purified by distillation and filtration to achieve the purity required in the technical field of the present invention. The solvent content in the resist composition is preferably set so that the solid content concentration is 0.5 to 30.0% by mass, and more preferably so that it is 1.0 to 20.0% 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.

[0219] <Other Additives> This resist composition may contain other additives not listed above, as long as they do not hinder the effects of the present invention. Examples of other additives include resins different from the specific resin and hydrophobic resin, sensitizers, dissolution inhibitors, dyes, plasticizers, and compounds that promote solubility in the developer (for example, phenol compounds with a molecular weight of 1000 or less, and alicyclic or aliphatic compounds containing a carboxylic acid group). The above-mentioned "dissolution inhibitor" refers to a compound with a molecular weight of 3000 or less that decomposes due to the action of acid, reducing its solubility in organic developers.

[0220] 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.

[0221] Furthermore, this resist composition may contain water as an impurity. When water is present as an impurity, a lower water content 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, this 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 lower residual monomer content 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 this resist composition.

[0222] [Pattern Forming Method and Resist Film] The pattern forming method of the present invention is not particularly limited as long as it is a method of forming a pattern using the resist composition, but a preferred pattern forming method is one that comprises the steps of: (1) forming a resist film on a substrate using the resist composition; (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.

[0223] [Step (1)] Step (1) is a step in which a resist film is formed on a substrate using the resist composition. Details of the resist composition used in Step (1) are as described above.

[0224] One method for forming a resist film on a substrate using this resist composition is to coat the substrate with the resist composition. 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 pore size of the filter 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 up 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 derivatives thereof. In addition to resins, diatomaceous earth and glass may also be used.

[0225] 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.

[0226] This 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, it 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.

[0227] 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.

[0228] The present invention also includes a resist film formed by the resist composition. The resist film may be a resist film formed by step (1). The thickness of the resist film is not particularly limited, but 10 to 120 nm is preferred in terms of being able 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.

[0229] 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. 2013-061648, on the resist film. Specific examples of basic compounds that the topcoat may contain include the basic compounds that may be contained in this resist composition.

[0230] [Step (2)] Step (2) is a step of exposing the resist film formed in step (1). The exposure method includes irradiating the formed resist film with active light or radiation through a predetermined mask. Pattern exposure is preferred. 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. This resist composition is particularly suitable for pattern formation by ArF immersion lithography or EUV lithography. In other words, step (2) above is preferably a step of exposing the resist film using ArF or EUV.

[0231] It is preferable to bake (heat) the image after exposure but before developing. This process is also called post-exposure baking (PEB). 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.

[0232] [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.

[0233] 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.

[0234] 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. Bio-derived solvents can also be used as the organic solvent in the organic developer. Examples of bio-derived solvents suitably applicable to organic developers include those described in U.S. Patent Application Publication 2025 / 0068079A1, Proceedings of SPIE, 12957, 1295719 (2024), etc. The bio-derived solvent may be purified by distillation and filtration to achieve the purity required in the technical field of the present invention.

[0235] 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 relative to the organic developer is preferably 50 to 100% by mass, more preferably 80 to 100% by mass, even more preferably 90 to 100% by mass, and particularly preferably 95 to 100% by mass, based on the total amount of the organic developer.

[0236] 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 developer 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.

[0237] 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 of 9 to 12 carbon atoms in the organic developer (total amount if multiple types of hydrocarbons with 9 to 12 carbon atoms are included) 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.

[0238] 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.

[0239] Organic developers may contain other components in addition to organic solvents. Examples of other components include water, surfactants, antioxidants, and basic compounds.

[0240] [Other steps] The pattern forming method of the present invention may include other steps other than those described above.

[0241] <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. Preferably, the rinsing solution 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. Bio-derived solvents can also be used as the rinsing solution. Examples of bio-derived solvents include the bio-derived solvents exemplified as organic solvents in the organic developer solution described above.

[0242] 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).

[0243] Furthermore, the pattern formation method of the present invention may include a heating step (PB; 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).

[0244] 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.

[0245] In the pattern forming method of the present invention, the developer, the resist composition, and other various materials (e.g., solvent, rinse solution, anti-reflective film forming composition, top coat 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 metallic 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.

[0246] 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.

[0247] 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.

[0248] [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.).

[0249] 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.

[0250] [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.

[0251] [First Acid Generator and Comparative Acid Generator] The following compounds are used as the first acid generator and comparative acid generator. Compounds A-1 to A-19 are the first acid generators, and compound Z-1 is the comparative acid generator.

[0252]

[0253]

[0254] [Third Acid Generator] The following compounds are used as third acid generators.

[0255]

[0256]

[0257] [Specific Resins and Comparative Resins] The following resins are used as the first acid generator and comparative acid generator. Resins C-1 to C-28 are specific resins, and resin Y-1 is a comparative resin. In the resins below, the numbers in parentheses represent the content of each repeating unit relative to the total repeating units of the resin (unit: mol%). The weight-average molecular weight (Mw) and dispersion (Mw / Mn) of each resin can be measured by GPC (carrier: tetrahydrofuran (THF)) (polystyrene equivalent). The content of repeating units is as follows: １３ It can be measured using C-NMR (nuclear magnetic resonance).

[0258]

[0259]

[0260]

[0261]

[0262] [Specific Compounds and Comparative Compounds] The following compounds are used as specific compounds and comparative compounds. Compounds D-1 to D-16 are specific compounds, and compound X-1 is a comparative compound.

[0263]

[0264]

[0265] [Hydrophobic Resins] The following resins E-1 to E-11 are used as hydrophobic resins. In the resins listed below, the numbers in parentheses represent the content of each repeating unit (unit: mol%). The weight-average molecular weight (Mw) and dispersion (Mw / Mn) of the resin can be measured by GPC (carrier: THF) (polystyrene equivalent). The content of the repeating units is as follows: １３ It can be measured by C-NMR.

[0266]

[0267]

[0268] [Surfactant] F-1: PolyFox PF-6320 (manufactured by OMNOVA Solutions Inc., fluorine-based surfactant)

[0269] [Solvents] G-1: Propylene glycol monomethyl ether acetate (PGMEA) G-2: Propylene glycol monomethyl ether (PGME) G-3: γ-butyrolactone G-4: Ethyl lactate G-5: Cyclohexanone G-6: 2-heptanone

[0270] The table below shows the pKa values ​​of acids derived from each acid generator, and compounds generated from specific compounds by the action of active light or radiation.

[0271]

[0272] [Evaluation] [Examples 1-24 and Comparative Examples 1-3 (Positive Pattern Formation by ArF Exposure)] <Preparation and Storage of Resist Composition> Mix the components shown in the table below so that the solid content concentration is 3.0% by mass. Filter the resulting mixture through a polyethylene filter having a pore size of 0.03 μm to prepare the resist composition. Store the resulting resist composition at 4°C for 3 months.

[0273] <Pattern Formation> An organic anti-reflective film ARC29SR (manufactured by Brewer) is applied to a silicon wafer and baked at 205°C for 60 seconds to form an anti-reflective film with a thickness of 95 nm. On top of the anti-reflective film, each of the resist compositions shown in the table below is applied and baked at 100°C for 60 seconds to form a resist film with a thickness of 85 nm. An ArF excimer laser immersion scanner (manufactured by ASML; XT1700i, NA1.20) is used to expose the wafer through a 6% halftone mask of a 1:1 line-and-space pattern with a line width of 60 nm. Ultrapure water is used as the immersion solution. After exposure, the resist film is baked at 95°C for 60 seconds, then developed with an aqueous solution of tetramethylammonium hydroxide (2.38 mass%) for 30 seconds, and then rinsed with pure water for 30 seconds. After that, it is spin-dried to obtain a positive-type pattern.

[0274] <LWR Evaluation> A pattern formed with the exposure amount (optimal exposure amount) required to resolve a 1:1 line-and-space pattern with a line width of 60 nm is observed at 50 arbitrary locations from the top of the pattern using a length-measuring scanning electron microscope (SEM (Hitachi CG-4100)), and the standard deviation of the line width (σ, nm) is determined. The value of 3σ is taken as the LWR (nm), and the LWR after long-term storage is evaluated according to the following evaluation criteria. A smaller LWR value is preferable, and for practical purposes, an LWR evaluation of E or higher is preferable.

[0275] (Evaluation criteria) A: LWR≦3.3nm B: 3.3nm<LWR≦3.5nm C: 3.5nm<LWR≦3.8nm D: 3.8nm<LWR≦4.1nm E: 4.1nm<LWR≦4.4nm F: 4.4nm<LWR

[0276] [Examples 25-48 and Comparative Examples 4-6 (Negative Pattern Formation by ArF Exposure)] The resist compositions were prepared and stored in the same manner as in Examples 1-24 and Comparative Examples 1-3, except that they were prepared to have the compositions shown in Table 1 below. An organic anti-reflective film ARC29SR (manufactured by Brewer) was applied to a silicon wafer and baked at 205°C for 60 seconds to form an anti-reflective film with a thickness of 95 nm. Each resist composition shown in the table below was applied on top of the anti-reflective film and baked at 100°C for 60 seconds to form a resist film with a thickness of 85 nm. An ArF excimer laser immersion scanner (manufactured by ASML; XT1700i, NA1.20) was used to expose the film through a 6% halftone mask of a 1:1 line-and-space pattern with a line width of 60 nm. Ultrapure water was used as the immersion solution. After exposure, the resist film was heated at 95°C for 60 seconds and then developed with n-butyl acetate for 30 seconds. Subsequently, a negative pattern is obtained by spin-drying this material.

[0277] The LWR after long-term storage was evaluated using the same procedure and evaluation criteria as in Examples 1-24 and Comparative Examples 1-3.

[0278] [Examples 49-67 and Comparative Example 7 (Positive Pattern Formation by EUV Exposure)] <Preparation and Storage of Resist Composition> Mix the components shown in the table below so that the solid content concentration is 2.0% by mass. Prepare the resist composition by filtering the resulting mixture in the following order: first through a polyethylene filter with a pore size of 50 nm, then through a nylon filter with a pore size of 10 nm, and finally through a polyethylene filter with a pore size of 5 nm. Store the resulting resist composition at 4°C for 3 months.

[0279] <Pattern Formation> 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 1 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 an aqueous solution of tetramethylammonium hydroxide (2.38% by mass) for 30 seconds, followed by rinsing with pure water for 30 seconds. Finally, it is spin-dried to obtain a positive-type pattern.

[0280] <LWR Evaluation> Using the exposure amount (optimal exposure amount) required to resolve a 1:1 line-and-space pattern with a line width of 25 nm, the line width is observed at 50 arbitrary points from the top of the pattern using a length-measuring scanning electron microscope (SEM (Hitachi, Ltd. CG-4100)), and the standard deviation of the line width (σ, nm) is determined. The value of 3σ is taken as the LWR (nm), and the LWR after long-term storage is evaluated according to the following evaluation criteria. A smaller LWR value is preferable, and for practical purposes, an LWR evaluation of E or higher is preferable.

[0281] (Evaluation criteria) A: LWR≦3.3nm B: 3.3nm<LWR≦3.5nm C: 3.5nm<LWR≦3.8nm D: 3.8nm<LWR≦4.1nm E: 4.1nm<LWR≦4.4nm F: 4.4nm<LWR

[0282] [Examples 68-86 and Comparative Example 8 (Negative Pattern Formation by EUV Exposure)] The resist compositions were prepared and stored in the same manner as in Examples 49-67 and Comparative Example 8, except that they were prepared to have the compositions shown in Table 1 below. The underlayer film formation composition AL412 (manufactured by Brewer Science) was applied to a silicon wafer and baked at 205°C for 60 seconds to form an underlayer film with a thickness of 20 nm. The resist compositions shown in Table 1 below were 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. A silicon wafer having the obtained resist film was pattern-irradiated 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, and then developed with n-butyl acetate for 30 seconds. A negative-type pattern is obtained by spin-drying this.

[0283] The LWR after long-term storage was evaluated using the same procedure and evaluation criteria as in Examples 49-67 and Comparative Example 7.

[0284] [Results] The table below shows the composition of each resist composition and the evaluation results obtained. In the table, the "mass%" column shows the content (mass%) of each component relative to the total solids in the resist composition. When two or more types of components are used, the types and their contents are shown separated by " / ". The order in which the types and contents separated by " / " are listed corresponds. For example, the resist composition Re-19 of Example 19 contains compound A-10 at 12.6 mass% relative to the total solids of Re-19 as the first acid generator, and compound A-17 at 1.0 mass% relative to the total solids of Re-19. In the table, the solvent column shows the type of solvent and the mixing ratio (mass ratio). The order in which the types and mass ratios of solvents are listed corresponds. For example, the resist composition Re-2 of Example 2 uses a mixed solvent of G-1 / G-4 = 80 / 20 (mass ratio) as the solvent. Table 3 is a continuation of Table 2, and Table 5 is a continuation of Table 4. For example, the resist composition Re-1 of Example 1 contains compound A-1, resin C-4, compound D-3, resin E-3, and surfactant F-1, with solvent G-1, and an LWR rating of C.

[0285]

[0286]

[0287]

[0288]

[0289] From the results shown in the table above, it can be confirmed that this resist composition can form patterns with a low LWR even after long-term storage. From the results shown in the table above, it can be confirmed that the effect of the present invention is even better when the first acid has an alicyclic structure. From the results shown in the table above, in formula (1), L １ However, -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ - or -CR Ｌ４ R Ｌ５ - If this is the case, the effect of the present invention is better, -O-CR Ｌ１ R Ｌ２ -, -S-, or -SO ２- If this is the case, it can be confirmed that the effects of the present invention are even better. From the results shown in the table above, it can be confirmed that the effects of the present invention are even better when the specific compound includes compounds represented by formulas (D1) to (D5), in which the α-valent organic group is an α-valent aliphatic group and the mono-valent organic group is a mono-valent aliphatic group. From the results shown in the table above, it can be confirmed that the effects of the present invention are even better when the specific compound includes compounds represented by formulas (D1) to (D3). From the results shown in the table above, it can be confirmed that the effects of the present invention are even better when T in formula (P1) is a single bond.

Claims

A first acid generator that generates an acid represented by formula (1) and having a pKa of less than -0.75 upon the action of active light or radiation, A resin having repeating units represented by formula (P1), A photosensitive or radiation-sensitive resin composition comprising: a second acid generator that generates an acid with a pKa of -0.75 or higher upon the action of active light or radiation; and at least one specific compound selected from the group consisting of a second compound that generates a compound different from the acid represented by formula (1) upon the action of active light or radiation, comprising a nitrogen atom bonded to three atoms selected from carbon and hydrogen atoms, and a sulfonic acid group. In formula (1), R １ This represents an n-valent aliphatic group. L １ each independently represent -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ -, -NR Ｌ３ -, -O-CO-O-, or -CR Ｌ４ R Ｌ５ -. R Ｌ１ to R Ｌ５ each independently represent a hydrogen atom, a monovalent aliphatic group, a halogen atom, or a cyano group. L １ ga-O-CR Ｌ１ R Ｌ２ - If R １ , R Ｌ１ , and R Ｌ２ Two or more selected from may be bonded to each other to form an alicyclic ring which may have substituents, L １ ga-NR Ｌ３ - If R １ and R Ｌ３ They may be bonded to each other to form an alicyclic ring which may have substituents, L １ ga-CR Ｌ４ R Ｌ５ - If R １ , R Ｌ４ , and R Ｌ５ Two or more selected from these may be bonded to each other to form an alicyclic ring which may have substituents. Each Ar independently represents an s+2 valent aromatic ring group. Each X independently represents a halogen atom or a monovalent hydrocarbon group containing a halogen atom. s represents an integer greater than or equal to 1. 　 n represents an integer greater than or equal to 1. In formula (P1), Xa １ represents a hydrogen atom, alkyl group, cyano group, or halogen atom. T represents a single bond or a divalent linking group. Lx １ is a single bond or -CRx ４ Rx ５ Represents -O-. Rx ４ and Rx ５ Each of these independently represents either a hydrogen atom or a monovalent organic group. Rx １ ~Rx ３ Two of these groups are bonded together to form a monocycle, while the remaining one represents an alkyl group, cycloalkyl group, alkenyl group, alkynyl group, or aryl group. 　 The photosensitive or radiation-sensitive resin composition according to claim 1, wherein the specified compound includes a compound represented by any one of formulas (D1) to (D5). In formulas (D1) to (D5), R Ｎ１ This represents an α-valent organic group containing a nitrogen atom bonded to three atoms selected from the carbon and hydrogen atoms. R ｄ１ This represents an α-valent organic group that does not contain a nitrogen atom and is bonded to three atoms selected from the carbon and hydrogen atoms. R ｄ２ , R ｄ３ , and R ｄ５ Each of these independently represents an α-valent organic group. R ｄ４ , R ｄ６ , and R ｄ７ Each of these independently represents a monovalent organic group. R ｄ３ and a number of R ｄ４ Two or more selected from may be bonded to each other to form a ring which may have substituents, R ｄ５ a number of R ｄ６ , and a number of R ｄ７ Two or more elements selected from these may be bonded to each other to form a ring which may have substituents. Y ｄ１ and Y ｄ２ These are, independently, a single bond, -CO-, -SO-, or -SO ２ It represents -. However, Y ｄ１ and Y ｄ２ At least one of them is -CO-, -SO-, or -SO ２ It represents -. M ｆ＋ This represents a cation with an f-valence. f represents an integer greater than or equal to 1. 　 'a' represents an integer greater than or equal to 1. b represents an integer greater than or equal to 1. c represents an integer greater than or equal to 1. However, a, b, c, and f satisfy the relationship a × b = c × f. 　 The photosensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein in formula (1), X is a fluorine atom or a monovalent hydrocarbon group having a fluorine atom. 　 The photosensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the acid represented by formula (1) has an alicyclic structure. 　 In the above formulas (D1) to (D5), R Ｎ１ This is an α-valent aliphatic group containing a nitrogen atom bonded to three atoms selected from carbon and hydrogen atoms, R ｄ１ This is an α-valent aliphatic group that does not contain a nitrogen atom and is bonded to three atoms selected from the carbon and hydrogen atoms. R ｄ２ , R ｄ３ , and R ｄ５ However, each is independently an aliphatic group with valency α, R ｄ４ , R ａ６ , and R ｄ７ The photosensitive or radiation-sensitive resin composition according to claim 2, wherein each is independently a monovalent aliphatic group. 　 The photosensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein in formula (P1), T is a single bond. 　 In the above formula (1), L １ However, -O-CR Ｌ１ R Ｌ２ -, -S-, -SO-, -SO ２ - or -CR Ｌ４ R Ｌ５ - The photosensitive or radiation-sensitive resin composition according to claim 1 or 2. 　 In the above formula (1), L １ However, -O-CR Ｌ１ R Ｌ２ -, -S-, or -SO ２ - The photosensitive or radiation-sensitive resin composition according to claim 1 or 2. 　 The photosensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the specified compound includes a compound represented by any one of the formulas (D1) to (D3). 　 The photosensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the first acid generator comprises a sulfonium cation or an iodonium cation. A resist film formed using the photosensitive or radiation-sensitive resin composition according to claim 1 or 2. 　 A step of forming a resist film on a substrate using the photosensitive or radiation-sensitive resin composition according to claim 1 or 2, The steps include: exposing the resist film, A method for forming a pattern, comprising the step of developing the exposed resist film using a developer to form a pattern. 　 A method for manufacturing an electronic device, comprising the pattern forming method described in claim 12.

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