WO2024101378A1

WO2024101378A1 - Active-ray-sensitive or radioactive-ray-sensitive resin composition, active-ray-sensitive or radioactive-ray-sensitive film, pattern formation method, and electronic device manufacturing method

Info

Publication number: WO2024101378A1
Application number: PCT/JP2023/040157
Authority: WO
Inventors: 修平山口
Original assignee: 富士フイルム株式会社
Priority date: 2022-11-11
Filing date: 2023-11-08
Publication date: 2024-05-16
Also published as: TW202428650A

Abstract

Provided are: an active-ray-sensitive or radioactive-ray-sensitive resin composition comprising a resin (A) and a salt (B) having a cation radical structure; an active-ray-sensitive or radioactive-ray-sensitive film in which the active-ray-sensitive or radioactive-ray-sensitive resin composition is used; a pattern formation method comprising a step for forming an active-ray-sensitive or radioactive-ray-sensitive film on a substrate using the active-ray-sensitive or radioactive-ray-sensitive resin composition, a step for exposing the active-ray-sensitive or radioactive-ray-sensitive film to light, and a step for developing the light-exposed active-ray-sensitive or radioactive-ray-sensitive film using a developing solution; and an electronic device manufacturing method.

Description

Actinic ray-sensitive or radiation-sensitive resin composition, actinic ray-sensitive or radiation-sensitive film, pattern forming method, and method for manufacturing electronic device

The present invention relates to an actinic ray- or radiation-sensitive resin composition, an actinic ray- or radiation-sensitive film, a pattern forming method, and a method for manufacturing an electronic device. More specifically, the present invention relates to an actinic ray- or radiation-sensitive resin composition, an actinic ray- or radiation-sensitive film, a pattern forming method, and a method for manufacturing an electronic device that can be suitably used in ultra-microlithography processes applicable to the manufacturing process of ultra-LSI (Large Scale Integration) and high-capacity microchips, the mold creation process for nanoimprinting, and the manufacturing process of high-density information recording media, as well as other photofabrication processes.

Traditionally, in the manufacturing process of semiconductor devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integration), fine processing is performed by lithography using a resist composition. In recent years, with the increasing integration of integrated circuits, there has been a demand for the formation of ultra-fine patterns in the submicron or quarter-micron range. Accordingly, there has been a trend toward shorter exposure wavelengths, from g-line to i-line and then to KrF excimer laser light, and currently an exposure machine using an ArF excimer laser with a wavelength of 193 nm as a light source has been developed. In addition, as a technology for further increasing resolution, the so-called immersion method, in which a high refractive index liquid (hereinafter also referred to as "immersion liquid") is filled between the projection lens and the sample, has been developed.

Currently, in addition to excimer laser light, lithography using electron beams (EB), X-rays, extreme ultraviolet rays (EUV), and other light sources is also being developed. Accordingly, resist compositions that are effectively sensitive to various types of actinic rays or radiation are being developed.

For example, Patent Document 1 describes a radiation-sensitive resin composition that contains a resin and a carboxylate anion-containing compound and a sulfonate anion-containing compound as radiation-sensitive acid generators.

WO 2008/66011

However, in forming extremely fine patterns (for example, a line width or space width of 50 nm or less), it is becoming difficult to achieve both line width roughness (LWR) performance and reduction in development defects.
The LWR performance refers to the ability to reduce the LWR of a pattern.

The present invention aims to provide an actinic ray-sensitive or radiation-sensitive resin composition that has excellent LWR performance and can reduce development defects in the formation of extremely fine patterns (e.g., line width or space width of 50 nm or less). Another objective of the present invention is to provide an actinic ray-sensitive or radiation-sensitive film, a pattern formation method, and a method for manufacturing an electronic device that use the actinic ray-sensitive or radiation-sensitive resin composition.

The inventors have discovered that the above problems can be solved by the following configuration.

[1]
An actinic ray-sensitive or radiation-sensitive resin composition comprising a resin (A) and a salt having a cation radical structure (B).

[2]
The actinic ray-sensitive or radiation-sensitive resin composition according to [1], wherein the salt (B) is a compound represented by the following general formula (B-1) or (B-2):

In general formula (B-1), Rb ₁ to Rb ₄ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a thiol group, an alkylthio group, an arylthio group, an amino group, a heteroaryl group, a carbonyl group, a cyano group, or a group consisting of a combination thereof, and may be bonded to each other to form a ring. A ₁ ^- represents a counter anion.
In the general formula (B-2), Rb ₅ to Rb ₁₂ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a thiol group, an alkylthio group, an arylthio group, an amino group, a carbonyl group, a hydroxyl group, a cyano group, or a group consisting of a combination thereof. _{Rb 13} represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group. X represents -S-, -O-, or -NRb ₁₄ -. Rb ₁₄ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group. Rb ₅ to Rb ₁₄ may be bonded to each other to form a ring. A ₂ ^- represents a counter anion.

[3]
The actinic ray-sensitive or radiation-sensitive resin composition according to [1] or [2], wherein the salt (B) has a carboxylate anion or a sulfonate anion as a counter anion.

[4]
The actinic ray-sensitive or radiation-sensitive resin composition according to [2], wherein A ₁ ^- in the above general formula (B-1) or A ₂ ^- in the above general formula (B-2) is represented by any one of the following general formulae (AN1) to (AN3):

In formula (AN1), A _Q1 ^- represents a carboxylate anion or a sulfonate anion. R ¹ and R ² each independently represent a hydrogen atom or a substituent. L _Q1 represents a divalent linking group. R ³ represents an organic group.

In the general formula (AN2), A _Q2 ^- represents a carboxylate anion or a sulfonate anion. Xf represents a hydrogen atom, a fluorine atom, an alkyl group substituted with at least one fluorine atom, or an organic group having no fluorine atom. R ⁴ and R ⁵ each independently represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom. L _Q2 represents a divalent linking group. W represents an organic group. o represents an integer of 1 to 3. p represents an integer of 0 to 10. q represents an integer of 0 to 10. A plurality of Xf may be the same as or different from each other. When p represents an integer of 2 or more, a plurality of R ⁴ and R ⁵ may be the same as or different from each other. When q represents an integer of 2 or more, a plurality of L _Q2 may be the same as or different from each other.

In general formula (AN3), A _Q3 ^- represents a carboxylate anion or a sulfonate anion. Ar represents an aromatic group. n and m represent integers of 0 or more. D represents a single bond or a divalent linking group. B represents a hydrocarbon group. E represents a substituent other than a carboxylate anion, a sulfonate anion, and a -(D-B) group. When n represents an integer of 2 or more, a plurality of Ds and Bs may be the same as or different from each other. When m represents an integer of 2 or more, a plurality of Es may be the same as or different from each other.

[5]
The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [4], wherein the resin (A) is a resin having a group that is decomposed by the action of an acid to increase polarity.

[6]
The actinic ray-sensitive or radiation-sensitive resin composition according to any one of items [1] to [5], wherein the resin (A) has at least one repeating unit selected from the group consisting of a repeating unit represented by the following general formula (A-1) and a repeating unit represented by the following general formula (A-2):

In formula (A-1), Ra ₁ to Ra ₃ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
_La1 represents a single bond or a divalent linking group.
Ra ₄ to Ra ₆ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, or an alkenyl group. Two of Ra ₄ to Ra ₆ may be bonded to each other to form a ring.
Ra ₀ represents an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, a hydroxyl group, an alkoxy group, an acyloxy group, an alkoxycarbonyl group, a halogen atom, or a cyano group. When a plurality of Ra ₀ are present, the plurality of Ra ₀ may be the same or different.
Two of Ra ₁ to Ra ₃ , La ₁ and Ra ₀ may be bonded to each other to form a ring.
na represents an integer of 0 to 4. ma represents an integer of 0 to 2.
In formula (A-2), Ra ₇ to Ra ₉ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
_La2 represents a single bond or a divalent linking group.
Ara represents an aromatic ring group.
Ra ₁₀ to Ra ₁₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, an alkoxy group, a cycloalkyloxy group, or an alkenyl group.
At least two of Ra ₁₀ to Ra ₁₂ may be bonded to each other to form a ring.
At least one of Ra ₉ to Ra ₁₂ may be bound to Ara.

[7]
The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [6], further comprising a compound that generates an acid upon irradiation with actinic rays or radiation.
[8]
An actinic ray-sensitive or radiation-sensitive film formed from the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [7].

[9]
A pattern forming method comprising the steps of: forming an actinic ray-sensitive or radiation-sensitive film on a substrate using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of items [1] to [7]; exposing the actinic ray-sensitive or radiation-sensitive film; and developing the exposed actinic ray-sensitive or radiation-sensitive film using a developer.
[10]
A method for producing an electronic device, comprising the pattern formation method according to [9].

According to the present invention, it is possible to provide an actinic ray-sensitive or radiation-sensitive resin composition which is excellent in LWR performance and capable of reducing development defects in the formation of an extremely fine pattern (for example, a line width or space width of 50 nm or less).
The present invention also provides an actinic ray-sensitive or radiation-sensitive film, a pattern forming method, and a method for producing an electronic device, which use the actinic ray-sensitive or radiation-sensitive resin composition.

The present invention will be described in detail below.
The following description of the components may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment.

In this specification, "actinic rays" or "radiation" refers to, for example, the emission line spectrum of a mercury lamp, far ultraviolet rays represented by excimer lasers, extreme ultraviolet rays (EUV: Extreme Ultraviolet), X-rays, soft X-rays, and electron beams (EB: Electron Beam).
In this specification, "light" means actinic rays or radiation.
In this specification, unless otherwise specified, "exposure" includes not only exposure to the emission line spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light, X-rays, EUV, and the like, but also drawing with particle beams such as electron beams and ion beams.
In this specification, the use of "to" means that the numerical values before and after it are included as the lower limit and upper limit.

In this specification, (meth)acrylate refers to at least one of acrylate and methacrylate. Also, (meth)acrylic acid refers to at least one of acrylic acid and methacrylic acid.

In this specification, the weight average molecular weight (Mw), number average molecular weight (Mn), and dispersity (also called molecular weight distribution) (Mw/Mn) of the resin are defined as polystyrene equivalent values measured using a Gel Permeation Chromatography (GPC) device (Tosoh Corporation HLC-8120GPC) (solvent: tetrahydrofuran, flow rate (sample injection amount): 10 μL, column: Tosoh Corporation TSK gel Multipore HXL-M, column temperature: 40°C, flow rate: 1.0 mL/min, detector: refractive index detector).

In the present specification, the notation of groups (atomic groups) that does not indicate whether they are substituted or unsubstituted includes groups that have a substituent as well as groups that have no substituent. For example, the term "alkyl group" includes not only alkyl groups that have no substituent (unsubstituted alkyl groups) but also alkyl groups that have a substituent (substituted alkyl groups). In addition, the term "organic group" in the present specification refers to a group that contains at least one carbon atom.
Unless otherwise specified, the substituent is preferably a monovalent substituent. Examples of the substituent include a monovalent nonmetallic atomic group other than a hydrogen atom, and can be selected from the following substituents T.

(Substituent T)
Examples of the substituent T include halogen atoms such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom; alkoxy groups such as a methoxy group, an ethoxy group, and a tert-butoxy group; a cycloalkyloxy group; an aryloxy group such as a phenoxy group and a p-tolyloxy group; an alkoxycarbonyl group such as a methoxycarbonyl group and a butoxycarbonyl group; a cycloalkyloxycarbonyl group; an aryloxycarbonyl group such as a phenoxycarbonyl group; an acyloxy group such as an acetoxy group, a propionyloxy group, and a benzoyloxy group; an acetyl group, a benzoyl group, an isobutyryl group, Examples of the substituent T include acyl groups such as acryloyl, methacryloyl, and methoxalyl groups; sulfanyl groups; alkylsulfanyl groups such as methylsulfanyl and tert-butylsulfanyl groups; arylsulfanyl groups such as phenylsulfanyl and p-tolylsulfanyl groups; alkyl groups; alkenyl groups; cycloalkyl groups; aryl groups; aromatic heterocyclic groups; hydroxy groups; carboxyl groups; formyl groups; sulfo groups; cyano groups; alkylaminocarbonyl groups; arylaminocarbonyl groups; sulfonamide groups; silyl groups; amino groups; carbamoyl groups; and the like. In addition, when these substituents can further have one or more substituents, examples of the substituent T also include groups having one or more substituents selected from the above-mentioned substituents as the further substituents (for example, monoalkylamino groups, dialkylamino groups, arylamino groups, trifluoromethyl groups, etc.).

In this specification, the bonding direction of the divalent groups is not limited unless otherwise specified. For example, when Y is -COO- in a compound represented by the formula "X-Y-Z", Y may be -CO-O- or -O-CO-. The above compound may be "X-CO-O-Z" or "X-O-CO-Z".

In this specification, the acid dissociation constant (pKa) refers to the pKa in an aqueous solution, and specifically, it is a value calculated based on a database of Hammett's substituent constants and known literature values using the following software package 1. 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).

In addition, pKa can also be obtained by molecular orbital calculation. A specific example of this method is a method of calculating H ⁺ dissociation free energy in an aqueous solution based on a thermodynamic cycle. The H ⁺ dissociation free energy can be calculated, for example, by DFT (density functional theory), but various other methods have been reported in literature, and the calculation method is not limited to this. There are several software programs that can perform DFT, and Gaussian16 is an example.

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

In this specification, "solids" refers to components that form an actinic ray-sensitive or radiation-sensitive film, and does not include solvents. In addition, any component that forms an actinic ray-sensitive or radiation-sensitive film is considered to be a solid even if it is in liquid form.

[Actinic ray- or radiation-sensitive resin composition]
The actinic ray-sensitive or radiation-sensitive resin composition of the present invention (also referred to as "the composition of the present invention") contains a resin (A) and a salt having a cation radical structure (B).

According to the composition of the present invention, by adopting the above-mentioned constitution, it is possible to obtain an actinic ray-sensitive or radiation-sensitive resin composition which is excellent in LWR performance and capable of reducing development defects in the formation of an extremely fine pattern (for example, a line width or space width of 50 nm or less).
The reason for this is not clear, but the present inventors speculate as follows.
The salt (B) contained in the composition of the present invention is a salt having a cation radical structure. Here, the cation radical structure means a radical structure having a positive charge, and the salt having a cation radical structure means a salt having a cation moiety and an anion moiety, and further having a radical in the cation moiety.
When the composition of the present invention is irradiated with actinic rays or radiation, radicals are generated. In addition, the photoacid generator that may be contained in the composition is decomposed by irradiation with actinic rays or radiation to finally generate an acid, and radicals are generated as intermediates. These radical intermediates often cause unexpected side reactions such as crosslinking reactions between compounds in the composition. Meanwhile, the radicals thus generated in the system are captured by the salt (B) due to the stability of the cation radical structure, and diffusion is suppressed. As a result, it is presumed that the above-mentioned effects are obtained by suppressing side reactions such as diffusion of the acid and crosslinking.

The composition of the present invention is typically a resist composition, and may be a positive resist composition or a negative resist composition. The composition of the present invention may be a resist composition for alkali development or a resist composition for organic solvent development.
The composition of the present invention may be a chemically amplified resist composition or a non-chemically amplified resist composition. The composition of the present invention is typically a chemically amplified resist composition.
The composition of the present invention can be used to form an actinic ray- or radiation-sensitive film. The actinic ray- or radiation-sensitive film formed using the composition of the present invention is typically a resist film.
First, the various components of the composition of the present invention will be described in detail below.

[Resin (A)]
The composition of the present invention contains a resin (A).
The resin (A) usually contains a group that decomposes under the action of an acid to increase its polarity (hereinafter also referred to as an "acid-decomposable group"), and preferably contains a repeating unit having an acid-decomposable group.
When the resin (A) has an acid-decomposable group, typically, in a pattern formation method using the composition of the present invention, when an alkaline developer is used as the developer, a positive pattern is preferably formed, and when an organic developer is used as the developer, a negative pattern is preferably formed.

The acid-decomposable group is typically a group that decomposes under the action of an acid to generate a polar group. The acid-decomposable group preferably has a structure in which the polar group is protected by a group (leaving group) that is eliminated under the action of an acid. Typically, the polarity of the resin (A) increases under the action of an acid, increasing its solubility in an alkaline developer and decreasing its solubility in an organic solvent.

The resin (A) preferably contains at least one repeating unit selected from the group consisting of repeating units represented by general formula (A-1) and repeating units represented by general formula (A-2). At least one repeating unit selected from the group consisting of repeating units represented by general formula (A-1) and repeating units represented by general formula (A-2) is preferably a repeating unit having an acid-decomposable group.

In formula (A-1), Ra ₁ to Ra ₃ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
_La1 represents a single bond or a divalent linking group.
Ra ₄ to Ra ₆ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, or an alkenyl group. Two of Ra ₄ to Ra ₆ may be bonded to each other to form a ring.
Ra ₀ represents an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, a hydroxyl group, an alkoxy group, an acyloxy group, an alkoxycarbonyl group, a halogen atom, or a cyano group. When a plurality of Ra ₀ are present, the plurality of Ra ₀ may be the same or different.
Two of Ra ₁ to Ra ₃ , La ₁ and Ra ₀ may be bonded to each other to form a ring.
na represents an integer of 0 to 4. ma represents an integer of 0 to 2.

In formula (A-2), Ra ₇ to Ra ₉ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
_La2 represents a single bond or a divalent linking group.
Ara represents an aromatic ring group.
Ra ₁₀ to Ra ₁₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, an alkoxy group, a cycloalkyloxy group, or an alkenyl group.
At least two of Ra ₁₀ to Ra ₁₂ may be bonded to each other to form a ring.
At least one of Ra ₉ to Ra ₁₂ may be bound to Ara.

(Repeating unit represented by formula (A-1))
In formula (A-1), Ra ₁ to Ra ₃ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
The alkyl groups of Ra ₁ to Ra ₃ may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The number of carbon atoms in the cycloalkyl group of Ra ₁ to Ra ₃ is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. As the cycloalkyl group of Ra ₁ to Ra ₃ , a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, and a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferable.
Examples of the halogen atom for Ra ₁ to Ra ₃ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom or an iodine atom is preferable.
The alkyl group contained in the alkoxycarbonyl group of Ra ₁ to Ra ₃ may be either linear or branched. The number of carbon atoms of the alkyl group contained in the alkoxycarbonyl group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.

La ₁ in the general formula (A-1) represents a single bond or a divalent linking group. Examples of the divalent linking group include a carbonyl group (-CO-), -O-, -S-, -SO-, -SO ₂ -, an amide group (-CONR-), a sulfonamide group (-SO ₂ NR-), an alkylene group, a cycloalkylene group, an alkenylene group, and a linking group in which a plurality of these groups are linked together. Each of the R groups represents a hydrogen atom or an organic group, and the organic group is preferably an alkyl group, a cycloalkyl group, an aryl group, or a combination thereof.
_La1 is preferably a single bond or —COO—, and more preferably a single bond.

In formula (A-1), Ra ₄ to Ra ₆ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, or an alkenyl group.

The alkyl groups of Ra ₄ to Ra ₆ may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 6. The methylene group contained in the alkyl groups of Ra ₄ to Ra ₆ may be substituted with at least one of -CO- and -O-.
The number of carbon atoms in the cycloalkyl group of Ra ₄ to Ra ₆ is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. As the cycloalkyl group of Ra ₄ to Ra ₆ , monocyclic cycloalkyl groups such as a cyclopentyl group and a cyclohexyl group, and polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferred.
The number of carbon atoms in the aryl group of Ra ₄ to Ra ₆ is not particularly limited, but is preferably from 6 to 20, and more preferably from 6 to 10. The aryl group of Ra ₄ to Ra ₆ is most preferably a phenyl group.
The aralkyl group of Ra ₄ to Ra ₆ is preferably a group in which one hydrogen atom in the alkyl group of the above-mentioned Ra ₄ to Ra ₆ is substituted with an aryl group having 6 to 10 carbon atoms (preferably a phenyl group), and examples thereof include a benzyl group.
The number of carbon atoms in the alkenyl group of Ra ₄ to Ra ₆ is not particularly limited, but is preferably from 2 to 5, and more preferably from 2 to 4. The alkenyl group of Ra ₄ to Ra ₆ is preferably a vinyl group.
The aromatic heterocyclic group of Ra ₄ to Ra ₆ preferably contains at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom. The number of heteroatoms contained in the aromatic heterocyclic group is preferably 1 to 5, more preferably 1 to 3. The number of carbon atoms in the aromatic heterocyclic group is not particularly limited, but is preferably 2 to 20, more preferably 3 to 15. The aromatic heterocyclic group may be a monocyclic or polycyclic ring. Examples of the aromatic heterocyclic group of Ra ₄ to Ra ₆ include a thienyl group, a furanyl group, a benzothienyl group, a dibenzothienyl group, a benzofuranyl group, a pyrrole group, an oxazolyl group, a thiazolyl group, a pyridyl group, an isothiazolyl group, and a thiadiazolyl group.

Two of Ra ₄ to Ra ₆ may be bonded to each other to form a ring. As the group in which two of Ra ₄ to Ra ₆ are bonded to form a ring, a cycloalkyl group is preferable. As the cycloalkyl group, a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group is preferable, and a monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferable. In the cycloalkyl group, one of the methylene groups constituting the ring may be replaced with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. In these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced with a vinylene group.

In general formula (A-1), -C(Ra ₄ )(Ra ₅ )(Ra ₆ ) is preferably a leaving group, and -COO-C(Ra ₄ )(Ra ₅ )(Ra ₆ ) is preferably such that -C(Ra ₄ )(Ra ₅ )(Ra ₆ ) is eliminated by the action of an acid to generate a carboxyl group.

In formula (A-1), Ra ₀ represents an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, a hydroxyl group, an alkoxy group, an acyloxy group, an alkoxycarbonyl group, a halogen atom, or a cyano group.
The alkyl group of Ra ₀ may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The number of carbon atoms in the cycloalkyl group of Ra ₀ is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. As the cycloalkyl groups of Ra ₁ to Ra ₃ , monocyclic cycloalkyl groups such as a cyclopentyl group and a cyclohexyl group, and polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferred.
Examples of the halogen atom for Ra ₀ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom or an iodine atom is preferable.
The alkyl group contained in the alkoxy group of Ra ₀ may be either linear or branched. The number of carbon atoms of the alkyl group contained in the alkoxy group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The alkyl group that can be contained in the acyloxy group of Ra ₀ may be either linear or branched. The number of carbon atoms in the alkyl group that can be contained in the acyloxy group of Ra ₀ is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The number of carbon atoms in the aryl group that can be contained in the acyloxy group of Ra ₀ is not particularly limited, but is preferably 6 to 20, and more preferably 6 to 10. The aryl group that can be contained in the acyloxy group of Ra ₀ is most preferably a phenyl group.
The alkyl group contained in the alkoxycarbonyl group of Ra ₀ may be either linear or branched. The number of carbon atoms of the alkyl group contained in the alkoxycarbonyl group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The number of carbon atoms in the aryl group of Ra ₀ is not particularly limited, but is preferably from 6 to 20, and more preferably from 6 to 10. The aryl group of Ra ₀ is most preferably a phenyl group.
The aromatic heterocyclic group of Ra ₀ preferably contains at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom. The number of heteroatoms contained in the aromatic heterocyclic group is preferably 1 to 5, more preferably 1 to 3. The number of carbon atoms in the aromatic heterocyclic group is not particularly limited, but is preferably 2 to 20, more preferably 3 to 15. The aromatic heterocyclic group may be monocyclic or polycyclic. Examples of the aromatic heterocyclic group of Ra ₀ include a thienyl group, a furanyl group, a benzothienyl group, a dibenzothienyl group, a benzofuranyl group, a pyrrole group, an oxazolyl group, a thiazolyl group, a pyridyl group, an isothiazolyl group, and a thiadiazolyl group.

In general formula (A-1), na represents an integer of 0 to 4, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.

In general formula (A-1), ma represents an integer of 0 to 2, preferably 0 or 1, and more preferably 0. The aromatic ring in general formula (A-1) is benzene when ma represents 0, naphthalene when ma represents 1, and anthracene when ma represents 2.

Specific examples of the repeating unit represented by general formula (A-1) are shown below, but are not limited to these.

(Repeating unit represented by formula (A-2))
In the general formula (A-2), Ra ₇ to Ra ₉ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. The explanation, specific examples, and preferred ranges for Ra ₇ to Ra ₉ are the same as the explanation, specific examples, and preferred ranges for Ra ₁ to Ra ₃ in the general formula (A-1) described above.

_La2 in the general formula (A-2) represents a single bond or a divalent linking group. The description, specific examples, and preferred ranges of _La2 are the same as the description, specific examples, and preferred ranges of _La1 in the general formula (A-1) described above.

In general formula (A-2), Ara represents an aromatic ring group. The aromatic ring group of Ara is preferably an arylene group, more preferably an arylene group having 6 to 20 carbon atoms, even more preferably an arylene group having 6 to 10 carbon atoms, particularly preferably a phenylene group or naphthylene group, and most preferably a phenylene group.

In formula (A-2), Ra ₁₀ to Ra ₁₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, an alkoxy group, a cycloalkyloxy group, or an alkenyl group.
The alkyl groups of Ra ₁₀ to Ra ₁₂ may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The number of carbon atoms in the cycloalkyl group of Ra ₁₀ to Ra ₁₂ is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. As the cycloalkyl group of Ra ₁₀ to Ra ₁₂ , monocyclic cycloalkyl groups such as a cyclopentyl group and a cyclohexyl group, and polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferred.
The alkyl group contained in the alkoxy group of Ra ₁₀ to Ra ₁₂ may be either linear or branched. The number of carbon atoms of the alkyl group contained in the alkoxy group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.
The number of carbon atoms in the cycloalkyl group contained in the cycloalkyloxy group of Ra ₁₀ to Ra ₁₂ is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. As the cycloalkyl group contained in the cycloalkyloxy group of Ra ₁₀ to Ra ₁₂ , a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, and a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferred.
The number of carbon atoms in the aryl group of Ra ₁₀ to Ra ₁₂ is not particularly limited, but is preferably from 6 to 20, and more preferably from 6 to 10. The aryl group of Ra ₁₀ to Ra ₁₂ is most preferably a phenyl group.
The aralkyl groups of Ra ₁₀ to Ra ₁₂ are preferably groups in which one hydrogen atom in the alkyl groups of Ra ₁₀ to Ra ₁₂ described above is substituted with an aryl group having 6 to 10 carbon atoms (preferably a phenyl group), and examples thereof include a benzyl group.
The number of carbon atoms in the alkenyl group of Ra ₁₀ to Ra ₁₂ is not particularly limited, but is preferably from 2 to 5, and more preferably from 2 to 4. The alkenyl group of Ra ₁₀ to Ra ₁₂ is preferably a vinyl group.
The aromatic heterocyclic groups of Ra ₁₀ to Ra ₁₂ preferably contain at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom. The number of heteroatoms contained in the aromatic heterocyclic group is preferably 1 to 5, more preferably 1 to 3. The number of carbon atoms in the aromatic heterocyclic group is not particularly limited, but is preferably 2 to 20, more preferably 3 to 15. The aromatic heterocyclic group may be a monocyclic or polycyclic ring. Examples of the aromatic heterocyclic groups of Ra ₁₀ to Ra ₁₂ include a thienyl group, a furanyl group, a benzothienyl group, a dibenzothienyl group, a benzofuranyl group, a pyrrole group, an oxazolyl group, a thiazolyl group, a pyridyl group, an isothiazolyl group, and a thiadiazolyl group.

At least two of Ra ₁₀ to Ra ₁₂ may be bonded to each other to form a ring. As the group in which Ra ₁₀ to Ra ₁₂ are bonded to form a ring, a cycloalkyl group is preferable. As the cycloalkyl group, a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group is preferable, and a monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferable. In the cycloalkyl group, one of the methylene groups constituting the ring may be replaced with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. In these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced with a vinylene group.

It is preferable that at least one of Ra ₁₀ to Ra ₁₂ is an alkoxy group, and it is more preferable that one of Ra ₁₀ to Ra ₁₂ is an alkoxy group and the other two are a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group.

In general formula (A-2), -C(Ra ₁₀ )(Ra ₁₁ )(Ra ₁₂ ) is preferably a leaving group, and -O-C(Ra ₁₀ )(Ra ₁₁ )(Ra ₁₂ ) is preferably such that -C(Ra ₁₀ )(Ra ₁₁ )(Ra ₁₂ ) is eliminated by the action of an acid to generate a hydroxy group (this hydroxy group is a phenolic hydroxyl group since it is bonded to Ara).

Specific examples of the repeating unit represented by general formula (A-2) are shown below, but are not limited to these.

The content of the repeating units selected from the group consisting of the repeating units represented by general formula (A-1) and the repeating units represented by general formula (A-2) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, based on the total repeating units in resin (A). The content of the repeating units selected from the group consisting of the repeating units represented by general formula (A-1) and the repeating units represented by general formula (A-2) is preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less, based on the total repeating units in resin (A).

The repeating units contained in resin (A) selected from the group consisting of repeating units represented by general formula (A-1) and repeating units represented by general formula (A-2) may be one type or two or more types. When two or more types are contained, it is preferable that the total content is within the above-mentioned preferred content range.

(Repeating Unit Having an Acid-Decomposable Group)
The resin (A) may contain a repeating unit having an acid-decomposable group other than those mentioned above.
The acid-decomposable group is preferably a group that is decomposed by the action of an acid to generate a polar group.
The polar group is preferably an alkali-soluble group, and examples thereof include acidic groups such as a carboxy group, a phenolic hydroxyl group, a fluorinated alcohol group, a sulfonic acid group, a phosphate group, a sulfonamide group, a sulfonylimide group, an (alkylsulfonyl)(alkylcarbonyl)methylene group, an (alkylsulfonyl)(alkylcarbonyl)imide group, a bis(alkylcarbonyl)methylene group, a bis(alkylcarbonyl)imide group, a bis(alkylsulfonyl)methylene group, a bis(alkylsulfonyl)imide group, a tris(alkylcarbonyl)methylene group, and a tris(alkylsulfonyl)methylene group, as well as an alcoholic hydroxyl group.

Examples of the leaving group which is eliminated by the action of an acid include groups represented by the formulae (Y1) to (Y4).
Formula (Y1): -C(Rx ₁ )(Rx ₂ )(Rx ₃ )
Formula (Y2): -C(=O)OC( _Rx1 )( _Rx2 )( _Rx3 )
Formula (Y3): -C(R ₃₆ )(R ₃₇ )(OR ₃₈ )
Formula (Y4): -C(Rn)(H)(Ar)

In formula (Y1) and formula (Y2), Rx ₁ to Rx ₃ each independently represent an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an aryl group (monocyclic or polycyclic), an aralkyl group (linear or branched), or an alkenyl group (linear or branched). When all of Rx ₁ to Rx ₃ are alkyl groups (linear or branched), it is preferable that at least two of Rx ₁ to Rx ₃ are methyl groups.
In particular, it is preferable that Rx ₁ to Rx ₃ each independently represent a linear or branched alkyl group, and it is more preferable that Rx ₁ to Rx ₃ each independently represent a linear alkyl group.
Two of Rx ₁ to Rx ₃ may be bonded to each other to form a ring (which may be either a monocyclic ring or a polycyclic ring).
The alkyl group of Rx ₁ to Rx ₃ 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.
The cycloalkyl groups of Rx ₁ to Rx ₃ are preferably monocyclic cycloalkyl groups such as a cyclopentyl group and a cyclohexyl group, and polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group.
The aryl group of Rx ₁ to Rx ₃ is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group.
The aralkyl group of Rx ₁ to Rx ₃ is preferably a group in which one hydrogen atom in the alkyl group of Rx ₁ to Rx ₃ described above is substituted with an aryl group having 6 to 10 carbon atoms (preferably a phenyl group), and examples thereof include a benzyl group.
The alkenyl group of Rx ₁ to Rx ₃ is preferably a vinyl group.
The ring formed by combining two of Rx ₁ to Rx ₃ is preferably a cycloalkyl group. The cycloalkyl group formed by combining two of Rx ₁ to Rx ₃ is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group, and more preferably a monocyclic cycloalkyl group having 5 to 6 carbon atoms.
In the cycloalkyl group formed by combining two of _Rx1 to _Rx3 , for example, one of the methylene groups constituting the ring may be replaced with a heteroatom such as an oxygen atom, a group having a heteroatom such as a carbonyl group, or a vinylidene group. In addition, in these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced with a vinylene group.
In the group represented by formula (Y1) or formula (Y2), for example, it is preferable that _Rx1 is a methyl group or an ethyl group, and _Rx2 and _Rx3 are bonded to form the above-mentioned cycloalkyl group.

In formula (Y3), R ₃₆ to R ₃₈ each independently represent a hydrogen atom or a monovalent organic group. R ₃₇ and R ₃₈ may be bonded to each other to form a ring. Examples of the monovalent organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group. It is also preferable that R ₃₆ is a hydrogen atom.
The alkyl group, cycloalkyl group, aryl group, and aralkyl group may contain a heteroatom such as an oxygen atom and/or a group having a heteroatom such as a carbonyl group. For example, the alkyl group, cycloalkyl group, aryl group, and aralkyl group may have one or more methylene groups replaced with a heteroatom such as an oxygen atom and/or a group having a heteroatom such as a carbonyl group.
In addition, R ₃₈ may be bonded to another substituent in the main chain of the repeating unit to form a ring. The group formed by bonding R ₃₈ to another substituent in the main chain of the repeating unit is preferably an alkylene group such as a methylene group.

In formula (Y4), Ar represents an aromatic ring group. Rn represents an alkyl group, a cycloalkyl group, or an aryl group. Rn and Ar may be bonded to each other to form a non-aromatic ring. Ar is more preferably an aryl group.

The content of repeating units having an acid decomposable group is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, based on all repeating units in resin (A). The content of repeating units having an acid decomposable group is preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less, based on all repeating units in resin (A).

The repeating units having an acid-decomposable group contained in resin (A) may be one type or two or more types. When two or more types are contained, it is preferable that the total content is within the above-mentioned range of the preferred content. Furthermore, when the repeating units having an acid-decomposable group include repeating units represented by the above-mentioned general formula (A-1) or (A-2), it is preferable that the total content including these is within the above-mentioned range of the preferred content.

(Repeating unit having a polar group)
The resin (A) preferably has a repeating unit having a polar group.
The repeating unit having a polar group is preferably a repeating unit selected from the group consisting of the repeating units represented by the general formula (A-1) and the repeating units represented by the general formula (A-2) described above, or a repeating unit other than a repeating unit having an acid-decomposable group.
Examples of the polar group of the repeating unit having a polar group include a hydroxyl group, a lactone group, a sultone group, a lactam group, an imide group, an amide group, a sulfonamide group, a carbonate group, a urethane group, a urea group, a nitrile group, a sulfoxide group, and a sulfonyl group. The polar group may be an acid group. The polar group is preferably a hydroxyl group or a lactone group, more preferably an aromatic hydroxyl group, and even more preferably a phenolic hydroxyl group.

The repeating unit having a polar group is preferably a repeating unit represented by the following general formula (A-3):

In formula (A-3), R ₁₀₁ , R ₁₀₂ and R ₁₀₃ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. R ₁₀₂ may bond with Ar ^A to form a ring, and in that case, R ₁₀₂ represents a single bond or an alkylene group.
L _A represents a single bond or a divalent linking group.
Ar _A represents an aromatic ring group.
k represents an integer of 1 to 5.

In the general formula (A-3), R ₁₀₁ , R ₁₀₂ and R ₁₀₃ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. The explanation, specific examples and preferred ranges of R ₁₀₁ , R ₁₀₂ and R ₁₀₃ are the same as the explanation, specific examples and preferred ranges of Ra ₁ to Ra ₃ in the general formula (A-1) described above.

Ar _A in the general formula (A-3) represents an aromatic ring group, more specifically, an aromatic ring group having a valence of (k+1). When k is 1, the divalent aromatic ring group is preferably an arylene group having 6 to 18 carbon atoms, such as a phenylene group, a tolylene group, a naphthylene group, or an anthracenylene group, or a divalent aromatic ring group containing a heterocycle, such as a thiophene ring, a furan ring, a pyrrole ring, a benzothiophene ring, a benzofuran ring, a benzopyrrole ring, a triazine ring, an imidazole ring, a benzimidazole ring, a triazole ring, a thiadiazole ring, or a thiazole ring. The aromatic ring group may have a substituent.
Specific examples of the (k+1)-valent aromatic ring group when k is an integer of 2 or more include groups obtained by removing any (k-1) hydrogen atoms from the above-mentioned specific examples of the divalent aromatic ring group.
The (k+1)-valent aromatic ring group may further have a substituent.
The substituent that the (k+1)-valent aromatic ring group may have is not particularly limited, and examples thereof include alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, hexyl, 2-ethylhexyl, octyl, and dodecyl groups; alkoxy groups such as methoxy, ethoxy, hydroxyethoxy, propoxy, hydroxypropoxy, and butoxy groups; and aryl groups such as phenyl groups.
Ar _A preferably represents an aromatic ring group having 6 to 18 carbon atoms, and more preferably represents a benzene ring group, a naphthalene ring group or a biphenylene ring group.

In formula (A-3), L 1 _A represents a single bond or a divalent linking group.
The divalent linking group represented by L _A is not particularly limited, and examples thereof include -COO-, -CONR ₆₄ -, an alkylene group, or a group formed by combining two or more of these groups, where R ₆₄ represents a hydrogen atom or an alkyl group.
The alkylene group is not particularly limited, but is preferably an alkylene group having 1 to 8 carbon atoms, such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, or an octylene group.
When R ₆₄ represents an alkyl group, examples of the alkyl group include alkyl groups having 20 or less carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a hexyl group, a 2-ethylhexyl group, an octyl group, and a dodecyl group, and an alkyl group having 8 or less carbon atoms is preferable.

The repeating unit represented by formula (A-3) preferably has a hydroxystyrene structure, that is, Ar _A preferably represents a benzene ring group.
k preferably represents an integer of 1 to 3, and more preferably represents 1 or 2.

Specific examples of the repeating unit represented by general formula (A-3) are shown below, but are not limited to these. In the formula, a represents an integer of 1 to 3.

The content of repeating units having a polar group in resin (A) is not particularly limited, but is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on the total repeating units in resin (A). In addition, the content of repeating units having a polar group is preferably 90 mol% or less, more preferably 85 mol% or less, and even more preferably 80 mol% or less, based on the total repeating units in resin (A).

The repeating units having a polar group contained in resin (A) may be of one type or of two or more types. When two or more types are contained, it is preferable that the total content is within the range of the preferred content described above.

(Repeating Unit Having a Lactone Group, a Sultone Group, or a Carbonate Group)
The resin (A) may have a repeating unit (hereinafter also referred to as "unit Y") having at least one type selected from the group consisting of a lactone group, a sultone group, and a carbonate group.
It is also preferred that the unit Y does not have a hydroxyl group or an acid group such as a hexafluoropropanol group.

The lactone group or sultone group may have a lactone structure or sultone structure. The lactone structure or sultone structure is preferably a 5- to 7-membered lactone structure or a 5- to 7-membered sultone structure. Among them, a 5- to 7-membered lactone structure having another ring structure condensed thereto in the form of a bicyclo structure or a spiro structure, or a 5- to 7-membered sultone structure having another ring structure condensed thereto in the form of a bicyclo structure or a spiro structure, is more preferred.
Regarding the resin (A), the description of [0120] to [0134] in WO 2022/024928 can be incorporated by reference.

(Repeating units having neither an acid decomposable group nor an acid group, and having a fluorine atom, a bromine atom or an iodine atom)
In addition to the repeating units described above, the resin (A) may have a repeating unit (hereinafter also referred to as unit X) that has neither an acid-decomposable group nor an acid group and has a fluorine atom, a bromine atom or an iodine atom. The <repeating unit that has neither an acid-decomposable group nor an acid group and has a fluorine atom, a bromine atom or an iodine atom> referred to here is preferably different from the above-mentioned <repeating unit having a lactone group, a sultone group or a carbonate group> and the below-mentioned <repeating unit having a photoacid generating group>.

The repeating unit X is preferably a repeating unit represented by formula (C).

_L5 represents a single bond or an ester group. _R9 represents a hydrogen atom or an alkyl group which may have a fluorine atom or an iodine atom. _R10 represents a hydrogen atom, an alkyl group which may have 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 combines these.

Examples of repeating units containing fluorine or iodine atoms are shown below.

The content of unit X is preferably 0 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on all repeating units in resin (A). The upper limit is preferably 50 mol% or less, more preferably 45 mol% or less, and even more preferably 40 mol% or less, based on all repeating units in resin (A).

The total content of repeating units containing at least one of a fluorine atom, a bromine atom, and an iodine atom in the repeating units of the resin (A) 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, based on the total repeating units of the resin (A). The upper limit is not particularly limited, but is, for example, 100 mol% or less based on the total repeating units of the resin (A).
Examples of the repeating unit containing at least one of a fluorine atom, a bromine atom, and an iodine atom include a repeating unit having a fluorine atom, a bromine atom, or an iodine atom and having an acid-decomposable group, a repeating unit having a fluorine atom, a bromine atom, or an iodine atom and having an acid group, and a repeating unit having a fluorine atom, a bromine atom, or an iodine atom.

(Repeating Unit Having a Photoacid Generating Group)
Resin (A) may have, as a repeating unit other than the above, a repeating unit having a group that generates an acid upon irradiation with actinic rays or radiation (preferably electron beams or extreme ultraviolet rays) (hereinafter also referred to as a "photoacid generating group").
An example of the repeating unit having a photoacid generating group is a repeating unit represented by formula (4).

R ⁴¹ represents a hydrogen atom or a methyl group. L ⁴¹ represents a single bond or a divalent linking group. L ⁴² represents a divalent linking group. R ⁴⁰ represents a structural moiety that is decomposed by irradiation with actinic rays or radiation to generate an acid in a side chain.
Examples of the repeating unit having a photoacid generating group are shown below, but the invention is not limited thereto.

Other examples of the repeating unit represented by formula (4) include the repeating units described in paragraphs [0094] to [0105] of JP 2014-041327 A and the repeating unit described in paragraph [0094] of WO 2018/193954 A.

When resin (A) contains a repeating unit having a photoacid generating group, the content of the repeating unit having a photoacid generating group is preferably 1 mol% or more, and more preferably 5 mol% or more, based on the total repeating units in resin (A). The upper limit is preferably 40 mol% or less, more preferably 35 mol% or less, and even more preferably 30 mol% or less, based on the total repeating units in resin (A).

(Repeating unit represented by formula (V-1) or the following formula (V-2))
The resin (A) may have a repeating unit represented by the following formula (V-1) or the following formula (V-2).
The repeating units represented by the following formulae (V-1) and (V-2) are preferably repeating units different from the repeating units described above.

In the formula,
_R6 and _R7 each independently represent 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 a fluorinated alkyl group having 1 to 6 carbon atoms), or a carboxyl group. As the alkyl group, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms is preferable.
_n3 represents an integer of 0 to 6.
_n4 represents an integer of 0 to 4.
_X4 is a methylene group, an oxygen atom, or a sulfur atom.
Examples of the repeating unit represented by formula (V-1) or (V-2) are shown below.
Examples of the repeating unit represented by formula (V-1) or (V-2) include the repeating units described in paragraph [0100] of WO 2018/193954.

(Repeating unit for reducing main chain mobility)
Resin (A) preferably has a high glass transition temperature (Tg) in order to suppress excessive diffusion of generated acid or pattern collapse during development. Tg is preferably higher than 90° C., more preferably higher than 100° C., even more preferably higher than 110° C., and particularly preferably higher than 125° C. In order to provide a superior dissolution rate in a developer, Tg is preferably 400° C. or lower, more preferably 350° C. or lower.
In this specification, the glass transition temperature (Tg) of a polymer such as resin (A) (hereinafter, "Tg of a repeating unit") is calculated by the following method. First, the Tg of a homopolymer consisting of only each repeating unit contained in the polymer is calculated by the Bicerano method. Next, the mass ratio (%) of each repeating unit to the total repeating units in the polymer is calculated. Next, the Tg at each mass ratio is calculated using the Fox formula (described in Materials Letters 62 (2008) 3152, etc.), and these are summed up to obtain the Tg (°C) of the polymer.
The Bicerano method is described in Prediction of Polymer Properties, Marcel Dekker Inc., New York (1993). The calculation of Tg by the Bicerano method can be performed using polymer property estimation software MDL Polymer (MDL Information Systems, Inc.).

In order to increase the Tg of the resin (A) (preferably to make the Tg exceed 90° C.), it is preferable to reduce the mobility of the main chain of the resin (A). Methods for reducing the mobility of the main chain of the resin (A) include the following methods (a) to (e).
(a) Introduction of a bulky substituent into the main chain; (b) Introduction of a plurality of substituents into the main chain; (c) Introduction of a substituent inducing an interaction between resins (A) in the vicinity of the main chain; (d) Formation of a main chain with a cyclic structure; (e) Linking of a cyclic structure to the main chain. Note that resin (A) preferably has a repeating unit showing a homopolymer Tg of 130° C. or higher.
The type of repeating unit exhibiting a homopolymer Tg of 130° C. or higher is not particularly limited, and may be any repeating unit exhibiting a homopolymer Tg of 130° C. or higher as calculated by the Bicerano method. Depending on the type of functional group in the repeating units represented by formulae (A) to (E) described below, the repeating unit may be one exhibiting a homopolymer Tg of 130° C. or higher.

One example of a specific means for achieving the above (a) is to introduce a repeating unit represented by formula (A) into resin (A).

In formula (A), _R represents a group containing a polycyclic structure. _Rx represents a hydrogen atom, a methyl group, or an ethyl group. The group containing a polycyclic structure is a group containing a plurality of ring structures, and the plurality of ring structures may be condensed or not condensed.
Specific examples of the repeating unit represented by formula (A) include those described in paragraphs [0107] to [0119] of WO 2018/193954.

One example of a specific means for achieving the above (b) is to introduce a repeating unit represented by formula (B) into resin (A).

In formula (B), R _b1 to R _b4 each independently represent a hydrogen atom or an organic group, and at least two of R _b1 to R _b4 represent an organic group.
When at least one of the organic groups is a group in which a ring structure is directly linked to the main chain in the repeating unit, the type of the other organic groups is not particularly limited.
Furthermore, when none of the organic groups has a ring structure directly linked to the main chain in the repeating unit, at least two of the organic groups are substituents having three or more constituent atoms excluding hydrogen atoms.
Specific examples of the repeating unit represented by formula (B) include those described in paragraphs [0113] to [0115] of WO 2018/193954.

One example of a specific means for achieving the above (c) is to introduce a repeating unit represented by formula (C) into resin (A).

In formula (C), R _c1 to R _c4 each independently represent a hydrogen atom or an organic group, and at least one of R _c1 to R _c4 is a group containing a hydrogen-bonding hydrogen atom within three atoms from a main chain carbon. In particular, in order to induce an interaction between the main chains of resin (A), it is preferable to have a hydrogen-bonding hydrogen atom within two atoms (closer to the main chain).
Specific examples of the repeating unit represented by formula (C) include those described in paragraphs [0119] to [0121] of WO 2018/193954.

One example of a specific means for achieving the above (d) is to introduce a repeating unit represented by formula (D) into resin (A).

In formula (D), "Cyclic" represents a group forming a main chain with a cyclic structure. The number of constituent atoms of the ring is not particularly limited.
Specific examples of the repeating unit represented by formula (D) include those described in paragraphs [0126] to [0127] of WO 2018/193954.

One example of a specific means for achieving the above (e) is to introduce a repeating unit represented by formula (E) into resin (A).

In formula (E), each Re independently represents a hydrogen atom or an organic group. Examples of the organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group, each of which may have a substituent.
"Cyclic" refers to a cyclic group containing carbon atoms in the main chain. The number of atoms contained in the cyclic group is not particularly limited.
Specific examples of the repeating unit represented by formula (E) include those described in paragraphs [0131] to [0133] of WO 2018/193954.

(Repeating unit having at least one group selected from a lactone group, a sultone group, a carbonate group, a hydroxyl group, a cyano group, and an alkali-soluble group)
The resin (A) may have a repeating unit having at least one type of group selected from a lactone group, a sultone group, a carbonate group, a hydroxyl group, a cyano group, and an alkali-soluble group.
Examples of the repeating unit having a lactone group, a sultone group, or a carbonate group contained in the resin (A) include the repeating units described above in <Repeat units having a lactone group, a sultone group, or a carbonate group>. The preferred content is also as described above in <Repeat units having a lactone group, a sultone group, or a carbonate group>.

The resin (A) may contain a repeating unit having a hydroxyl group or a cyano group, which improves the adhesion to the substrate and the affinity for the developer.
The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group.
The repeating unit having a hydroxyl group or a cyano group preferably does not have an acid-decomposable group. Examples of the repeating unit having a hydroxyl group or a cyano group include those described in paragraphs [0081] to [0084] of JP2014-098921A.

The resin (A) may have a repeating unit having an alkali-soluble group.
Examples of the alkali-soluble group include a carboxyl group, a sulfonamide group, a sulfonylimide group, a bissulfonylimide group, and an aliphatic alcohol group (e.g., a hexafluoroisopropanol group) substituted at the α-position with an electron-withdrawing group, with the carboxyl group being preferred. The resin (A) contains a repeating unit having an alkali-soluble group, which increases the resolution in contact hole applications. Examples of the repeating unit having an alkali-soluble group include those described in paragraphs [0085] and [0086] of JP 2014-098921 A.

(Repeating unit having an alicyclic hydrocarbon structure and not exhibiting acid decomposition property)
Resin (A) may have an alicyclic hydrocarbon structure and a repeating unit that does not exhibit acid decomposability. This can reduce elution of low molecular weight components from the resist film into the immersion liquid during immersion exposure. Examples of repeating units that have an alicyclic hydrocarbon structure and do not exhibit acid decomposability include repeating units derived from 1-adamantyl (meth)acrylate, diamantyl (meth)acrylate, tricyclodecanyl (meth)acrylate, or cyclohexyl (meth)acrylate.

(Repeating unit represented by formula (III) having neither a hydroxyl group nor a cyano group)
The resin (A) may have a repeating unit represented by formula (III) which has neither a hydroxyl group nor a cyano group.

In formula (III), _R5 represents a hydrocarbon group having at least one cyclic structure and having neither a hydroxyl group nor a cyano group.
Ra represents a hydrogen atom, an alkyl group or a -CH ₂ -O-Ra ₂ group, where Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
Examples of the repeating unit represented by formula (III) that does not have either a hydroxyl group or a cyano group include those described in paragraphs [0087] to [0094] of JP2014-098921A.

In addition to the repeating structural units described above, resin (A) may have various repeating structural units for the purpose of adjusting dry etching resistance, suitability for standard developing solutions, substrate adhesion, resist profile, resolution, heat resistance, sensitivity, etc.

As the resin (A), particularly when the composition of the present invention is used as an ArF actinic ray- or radiation-sensitive resin composition, it is preferable that all of the repeating units are composed of repeating units derived from a compound having an ethylenically unsaturated bond. In particular, it is also preferable that all of the repeating units are composed of (meth)acrylate-based repeating units. When all of the repeating units are composed of (meth)acrylate-based repeating units, any of the repeating units in which all of the repeating units are methacrylate-based repeating units, all of the repeating units are acrylate-based repeating units, or all of the repeating units are a mixture of methacrylate-based repeating units and acrylate-based repeating units can be used, and it is preferable that the acrylate-based repeating units account for 50 mol% or less of the total repeating units.

The resin (A) can be synthesized according to a conventional method (for example, radical polymerization).
The weight average molecular weight (Mw) of the resin (A), as calculated in terms of polystyrene by the GPC method, is preferably 30,000 or less, more preferably 1,000 to 30,000, even more preferably 3,000 to 30,000, and particularly preferably 5,000 to 15,000.
The dispersity (molecular weight distribution, Pd, Mw/Mn) of the resin (A) is preferably from 1 to 5, more preferably from 1 to 3, even more preferably from 1.2 to 3.0, and particularly preferably from 1.2 to 2.0. The smaller the dispersity, the better the resolution and resist shape, and furthermore, the smoother the sidewalls of the resist pattern are, and the better the roughness.

In the composition of the present invention, the content of the resin (A) is preferably from 40.0 to 99.9 mass %, more preferably from 60.0 to 90.0 mass %, based on the total solid content of the composition of the present invention.
Resin (A) may be used alone or in combination of two or more. When two or more resins are used, the total content is preferably within the above-mentioned suitable content range.

[Salt (B) having a cation radical structure]
The composition of the present invention contains a salt (B) having a cation radical structure (hereinafter, also simply referred to as "salt (B)").

As described above, salt (B) has a cation radical structure and thus has a radical scavenging function. Therefore, it is presumed that salt (B) can capture radicals generated in the system upon irradiation with actinic rays or radiation, and as a result, inhibit the diffusion of acid. In other words, salt (B) can function as an acid diffusion control agent in the composition of the present invention.

The structure of salt (B) is not particularly limited as long as it has a cation radical structure, but it is preferably a compound represented by the following general formula (B-1) or general formula (B-2).

In general formula (B-1), Rb ₁ to Rb ₄ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a thiol group, an alkylthio group, an arylthio group, an amino group, a heteroaryl group, a carbonyl group, a cyano group, or a group consisting of a combination thereof, and may be bonded to each other to form a ring. A ₁ ^- represents a counter anion.

Examples of the alkyl group represented by Rb ₁ to Rb ₄ include linear or branched alkyl groups having 1 to 10 carbon atoms, preferably linear or branched alkyl groups having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group.

Examples of the alkenyl group represented by Rb ₁ to Rb ₄ include linear or branched alkenyl groups having 2 to 10 carbon atoms, and linear or branched alkenyl groups having 2 to 4 carbon atoms are preferred.

Examples of the alkynyl group represented by Rb ₁ to Rb ₄ include linear or branched alkynyl groups having 2 to 10 carbon atoms, and linear or branched alkynyl groups having 2 to 4 carbon atoms are preferred.

Examples of the aryl group represented by Rb ₁ to Rb ₄ include aryl groups having 6 to 20 carbon atoms, preferably aryl groups having 6 to 10 carbon atoms, and more preferably a phenyl group.

Examples of the alkyl group contained in the alkoxy group represented by Rb ₁ to Rb ₄ include the alkyl groups as Rb ₁ to Rb ₄ described above, and preferred examples are also the same.

Examples of the alkyl group contained in the alkylthio group represented by Rb ₁ to Rb ₄ include the alkyl groups as Rb ₁ to Rb ₄ described above, and preferred examples thereof are also the same.

Examples of the aryl group contained in the arylthio group represented by Rb ₁ to Rb ₄ include the aryl groups as Rb ₁ to Rb ₄ described above, and preferred examples thereof are also the same.

The heteroaryl group represented by Rb ₁ to Rb ₄ preferably contains at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom. The number of carbon atoms in the heteroaryl group is not particularly limited, but is preferably 2 to 20, and more preferably 3 to 15. The heteroaryl group may be monocyclic or polycyclic. Examples of the heteroaryl group include a thienyl group, a furanyl group, a pyrrole group, an oxazolyl group, a thiazolyl group, an imidazolyl group, a pyridinyl group, an isothiazolyl group, and a thiadiazolyl group.

The group formed by combining two or more of these is not particularly limited, but examples thereof include a group formed by combining a carbonyl group with at least one group selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, and an alkoxy group.

The above groups represented by Rb ₁ to Rb ₄ may further have a substituent. Examples of the further substituent include the groups described above as Rb ₁ to Rb ₄ .

Rb ₁ to Rb ₄ may be bonded to each other to form a ring. In this case, it is preferable that Rb ₁ and Rb ₂ or Rb ₃ and Rb ₄ are bonded to form a ring, and either of them may be used.

The ring formed by bonding Rb ₁ to Rb ₄ together may be a monocyclic ring or a polycyclic ring, and may be an aromatic ring or a non-aromatic ring.

The ring formed by bonding Rb ₁ to Rb ₄ to each other is preferably a 5- to 7-membered ring.
The aromatic ring may be an aromatic hydrocarbon ring or an aromatic hetero ring.
The aromatic hydrocarbon ring is preferably a benzene ring.
The aromatic heterocycle is preferably an aromatic heterocycle containing at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom, and examples thereof include a thiophene ring, a furan ring, a pyrrole ring, an oxazole ring, a thiazole ring, an imidazole ring, a pyridine ring, an isothiazole ring, and a thiadiazole ring.

The non-aromatic ring may be an aliphatic hydrocarbon ring or an aliphatic hetero ring.
Examples of the aliphatic hydrocarbon ring include cycloalkane rings such as a cyclopentane ring, a cyclohexane ring, and a cycloheptane ring, and cycloalkene rings such as a cyclohexene ring.
The aliphatic heterocycle is preferably an aliphatic heterocycle containing at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom, and examples thereof include rings in which a methylene group contained in the above-mentioned aliphatic hydrocarbon ring is substituted with a group containing a heteroatom such as -O-, -S-, -S(=O) ₂ -, -C(=O)-, etc. Examples thereof include a ring formed by a -Y-(CH ₂ ) _n -Y- group (Y represents a sulfur atom or an oxygen atom, and n represents an integer of 1 to 3) together with two adjacent carbon atoms in the five-membered ring clearly shown in general formula (B-1) (specifically, the carbon atom to which Rb ₁ is bonded and the carbon atom to which Rb ₂ is bonded, or the carbon atom to which Rb ₃ is bonded and the carbon atom to which Rb ₄ is bonded).

The ring formed by bonding Rb ₁ to Rb ₄ together may further have a substituent. Examples of the further substituent include the groups described above for Rb ₁ to Rb ₄ .

Specific examples of the cation moiety having a cation radical structure of the compound represented by general formula (B-1) are shown below, but the present invention is not limited to these.

In formula (B-1), A ₁ ^- represents a counter anion.
The counter anion in the general formula (B-1) is not particularly limited, and examples thereof include organic anions such as sulfonate anion, carboxylate anion, sulfonylimide anion, bis(alkylsulfonyl)imide anion, and tris(alkylsulfonyl)methide anion. Among these, a carboxylate anion or a sulfonate anion is preferable.
The counter anion structure is more preferably a structure represented by any one of the following general formulas (AN1) to (AN3).

In formula (AN1), R ¹ and R ² each independently represent a hydrogen atom or a substituent.
The substituent is not particularly limited, but is preferably a group that is not an electron-withdrawing group. Examples of the group that is not an electron-withdrawing group include a hydrocarbon group, a hydroxyl group, an oxyhydrocarbon group, an oxycarbonylhydrocarbon group, an amino group, a hydrocarbon-substituted amino group, and a hydrocarbon-substituted amide group.
The groups which are not electron-withdrawing groups are preferably each independently -R', -OH, -OR', -OCOR', -NH ₂ , -NR' ₂ , -NHR' or -NHCOR', where R' is a monovalent hydrocarbon group.

Examples of the monovalent hydrocarbon group represented by R' include alkyl groups such as methyl, ethyl, propyl, and butyl; alkenyl groups such as ethenyl, propenyl, and butenyl; alkynyl groups such as ethynyl, propynyl, and butynyl; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornyl, and adamantyl; cycloalkenyl groups such as cyclopropenyl, cyclobutenyl, cyclopentenyl, and norbornenyl; aryl groups such as phenyl, tolyl, xylyl, mesityl, naphthyl, methylnaphthyl, anthryl, and methylanthryl; and aralkyl groups such as benzyl, phenethyl, phenylpropyl, naphthylmethyl, and anthrylmethyl.
Of these, it is preferable that R ¹ and R ² each independently represent a hydrocarbon group (preferably a cycloalkyl group) or a hydrogen atom.

_LQ1 represents a divalent linking group.
Examples of the divalent linking group include -O-CO-O-, -COO-, -CONH-, -CO-, -O-, -S-, -SO-, -SO ₂ -, alkylene groups (preferably having 1 to 6 carbon atoms), cycloalkylene groups (preferably having 3 to 15 carbon atoms), alkenylene groups (preferably having 2 to 6 carbon atoms), and divalent linking groups combining a plurality of these. Among these, the divalent linking group is preferably -O-CO-O-, -COO-, -CONH-, -CO-, -O-, -SO ₂ -, -O-CO-O-alkylene group-, -COO-alkylene group-, or -CONH-alkylene group-, and more preferably -O-CO-O-, -O-CO-O-alkylene group-, -COO-, -CONH-, -SO ₂ -, or -COO-alkylene group-.

L _Q1 is, for example, preferably a group represented by the following formula (AN1-1).
* ^a - ( ^CR2a2 ₎ _X - Q - ( ^CR2b2 ₎ _Y - * ^b (AN1-1)

In formula (AN1-1), * ^a represents the bonding position to R ³ in general formula (AN1).
* ^b represents the bonding position to --C(R ¹ )(R ² )-- in formula (AN1).
X and Y each independently represent an integer of 0 to 10, and preferably an integer of 0 to 3.
R ^2a and R ^2b each independently represent a hydrogen atom or a substituent.
When a plurality of R ^2a and a plurality of R ^2b are present, the plurality of R ^2a and R ^2b may be the same or different.
However, when Y is 1 or more, R ^2b in CR ^2b ₂ directly bonded to —C(R ¹ )(R ² )— in general formula (AN1) is other than a fluorine atom.
Q represents * ^A -O-CO-O-* ^B , * ^A -CO-* ^B , * ^A -CO-O-* ^B , * ^A -O-CO-* ^B , * ^A -O-* ^B , * ^A -S-* ^B , or * ^A - _SO2- * ^B .
However, when X+Y in formula (AN1-1) is 1 or more and both R ^2a and R ^2b in formula (AN1-1) are hydrogen atoms, Q represents * ^A -O-CO-O-* ^B , * ^A -CO-* ^B , * ^A -O-CO-* ^B , * ^A -O-* ^B , * ^A -S-* ^B or * ^A - _SO2- * ^B .
* ^A represents the bonding position on the ^R3 side in general formula (AN1), and * ^B represents the bonding position on the --SO ₃ ^-- side in general formula (AN1).

In formula (AN1), ^R3 represents an organic group.
The organic group is not particularly limited as long as it has one or more carbon atoms, and may be a linear group (e.g., a linear alkyl group), a branched group (e.g., a branched alkyl group such as a t-butyl group), or a cyclic group. The organic group may or may not have a substituent. The organic group may or may not have a heteroatom (such as an oxygen atom, a sulfur atom, and/or a nitrogen atom).

In particular, ^R3 is preferably an organic group having a cyclic structure. The cyclic structure may be a monocyclic or polycyclic ring and may have a substituent. The ring in the organic group having a cyclic structure is preferably directly bonded to _LQ1 in general formula (AN1).
The organic group having a cyclic structure may or may not have a heteroatom (such as an oxygen atom, a sulfur atom, and/or a nitrogen atom), for example. The heteroatom may substitute for one or more of the carbon atoms forming the cyclic structure.
The organic group having a cyclic structure is preferably, for example, a hydrocarbon group having a cyclic structure, a lactone ring group, or a sultone ring group, and among these, the organic group having a cyclic structure is preferably a hydrocarbon group having a cyclic structure.
The cyclic hydrocarbon group is preferably a monocyclic or polycyclic cycloalkyl group, which may have a substituent.
The cycloalkyl group may be a monocyclic group (such as a cyclohexyl group) or a polycyclic group (such as an adamantyl group), and preferably has 5 to 12 carbon atoms.

Xf represents a hydrogen atom, a fluorine atom, an alkyl group substituted with at least one fluorine atom, or an organic group having no fluorine atom. The number of carbon atoms in this alkyl group is preferably 1 to 10, and more preferably 1 to 4. The alkyl group substituted with at least one fluorine atom is preferably a perfluoroalkyl group.
Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, more preferably a fluorine atom or _CF3 , and further preferably both Xf are fluorine atoms.

^R4 and ^R5 each independently represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom. When a plurality ^{of R4s} and ^R5s are present, ^R4s and ^R5s may be the same or different.
The alkyl group represented by ^R4 and ^R5 preferably has 1 to 4 carbon atoms. The alkyl group may have a substituent. ^R4 and ^R5 are preferably a hydrogen atom.

_LQ2 represents a divalent linking group, and is defined _the same as _LQ1 in formula (AN1).

W represents an organic group containing a cyclic structure, and is preferably a cyclic organic group.
Examples of the cyclic organic group include an alicyclic group, an aryl group, and a heterocyclic group.
The alicyclic group may be a monocyclic or polycyclic. Examples of the monocyclic alicyclic group include monocyclic cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic group include polycyclic cycloalkyl groups such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. Among them, alicyclic groups having a bulky structure with 7 or more carbon atoms, such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group, are preferred.

The aryl group may be monocyclic or polycyclic, and examples of the aryl group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthryl group.
The heterocyclic group may be a single ring or a polycyclic ring. In particular, when the heterocyclic group is a polycyclic ring, the diffusion of the acid can be further suppressed. The heterocyclic group may have aromaticity or may not have aromaticity. Examples of heterocyclic rings having aromaticity include a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Examples of heterocyclic rings not having aromaticity include a tetrahydropyran ring, a lactone ring, a sultone ring, a piperidine ring, a piperazine ring, and a decahydroisoquinoline ring. The heterocyclic ring in the heterocyclic group is preferably a furan ring, a thiophene ring, a pyridine ring, or a decahydroisoquinoline ring.

The cyclic organic group may have a substituent. Examples of the substituent include an alkyl group (which may be either linear or branched, and preferably has 1 to 12 carbon atoms), a cycloalkyl group (which may be either monocyclic, polycyclic, or spirocyclic, and preferably has 3 to 20 carbon atoms), an aryl group (which preferably has 6 to 14 carbon atoms), a hydroxyl group, an alkoxy group, an ester group, an amide group, a urethane group, a ureido group, a thioether group, a sulfonamide group, and a sulfonate ester group. The carbon that constitutes the cyclic organic group (the carbon that contributes to the ring formation) may be a carbonyl carbon.

The anion represented by the general formula (AN2) is, for example, A _Q2A ^- -CF ₂ -CH ₂ -OCO-(L _Q2 ) _q' -W, A _Q2A ^- -CF ₂ -CHF-CH ₂ -OCO-(L _Q2 ) _q' -W, A _Q3 ^- -CF ₂ -COO-(L _Q2 ) _q' -W, A _Q3 ^- -CF ₂ -CF ₂ -CH ₂ -CH ₂ -(L _Q2 ) _q -W, A _Q2A ^- -CF ₂ -(L _Q2 ) _q -W, A _Q2A ^- -CF ₂ -CF ₂ -CF ₂ -(L _Q2 ) _q -W, or A _Q2A ^- -CF ₂ -CH(CF ₃ )-OCO-(L _Q2 ) _q' -W is preferred, where A _Q2A ^- , L _Q2 , q and W are the same as those in formula (AN2). A _Q2A ^- represents a carboxylate anion or a sulfonate anion. q' represents an integer of 0 to 10.

In general formula (AN3), Ar represents an aromatic group. The aromatic group is preferably an aryl group (e.g., a phenyl group).

n and m represent integers of 0 or more. n is preferably 0 to 4, and more preferably 0 to 3. m is preferably 0 to 3, and more preferably 0 to 2.

D represents a single bond or a divalent linking group. Examples of divalent linking groups include ether groups, thioether groups, carbonyl groups, sulfoxide groups, sulfone groups, sulfonate ester groups, ester groups, and groups consisting of combinations of two or more of these.

B represents a hydrocarbon group.
B is preferably an aliphatic hydrocarbon group, and more preferably a branched alkyl group such as an isopropyl group, a cycloalkyl group such as a cyclohexyl group, or an aryl group which may further have a substituent (eg, a tricyclohexylphenyl group).

E represents a substituent other than a carboxylate anion, a sulfonate anion, and a -(D-B) group. Examples of the substituent include a fluorine atom and a hydroxyl group.

The anion represented by the general formula (AN3) may be a benzenesulfonate anion, and is preferably a benzenesulfonate anion substituted with a branched alkyl group or cycloalkyl group.
The anion represented by formula (AN3) may be a benzoate anion. The benzoate anion may further have a substituent.

Examples of the counter anion A ₁ ⁻ also include anions represented by the following formulas (d1-1) to (d1-4).

In formula (d1-1), R ⁵¹ represents a hydrocarbon group which may have a substituent (for example, a hydroxyl group). The hydrocarbon group may be linear or branched, or may have a cyclic structure.

In formula (d1-2), Z ^2c represents a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (with the proviso that the carbon atom adjacent to S is not substituted with a fluorine atom).
The hydrocarbon group in Z ^2c may be linear or branched, or may have a cyclic structure. In addition, a carbon atom in the hydrocarbon group (preferably, when the hydrocarbon group has a cyclic structure, a carbon atom that is a ring atom) may be a carbonyl carbon (-CO-). Examples of the hydrocarbon group include a group having a norbornyl group which may have a substituent. The carbon atom forming the norbornyl group may be a carbonyl carbon.
It is preferable that "R ⁵¹ -COO ^- " in formula (d1-1) and "Z ^2c -SO ₃ ^- " in formula (d1-2) are different from the anions represented by the above formulae (AN1) to (AN3). For example, it is preferable that R ⁵¹ and Z ^2c are other than an aryl group. For example, in Z ^2c , the atoms at the α-position and the β-position relative to -SO ₃ ^- are preferably atoms other than a carbon atom having a fluorine atom as a substituent. For example, it is preferable that the atom at the α-position and/or the atom at the β-position relative to -SO ₃ ^- in Z ^2c is a ring member atom in a cyclic group.

In formula (d1-3), R ⁵² represents an organic group (preferably a hydrocarbon group having a fluorine atom), Y ³ represents a linear, branched, or cyclic alkylene group, an arylene group, or a carbonyl group, and Rf represents a hydrocarbon group.

In formula (d1-4), R ⁵³ and R ⁵⁴ each independently represent an organic group (preferably a hydrocarbon group having a fluorine atom), and R ⁵³ and R ⁵⁴ may be bonded to each other to form a ring.

The counter anion A ₁ ⁻ may have a group which is decomposed by the action of an acid, and may be an anion represented by the following general formula (cN1).

In general formula (cN1),
L _c1 represents a single bond or a divalent linking group. When a plurality of L _c1's are present, the plurality of L _c1's may be the same or different.
A _c1 represents a group which is decomposed by the action of an acid. When a plurality of A _c1's are present, the plurality of A _c1's may be the same or different.
n c represents an integer of 1 to 5.
Xc represents an (n+1)-valent linking group.

In formula (cN1), _Lc1 represents a single bond or a divalent linking group.
Examples of the divalent linking group represented by L _c1 include -CO-, -O-, -S-, -SO-, -SO ₂ -, hydrocarbon groups (e.g., alkylene groups, cycloalkylene groups, alkenylene groups, and arylene groups), and linking groups in which a plurality of these are linked together. Of these, L _c1 is preferably an alkylene group, an arylene group, -arylene group-alkylene group having a fluorine atom or an iodine atom-, a -COO-Rt- group, or a -O-Rt- group. In the formula, Rt represents an alkylene group or a cycloalkylene group.

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 atoms and iodine atoms contained in the alkylene group having a fluorine atom or an iodine atom is not particularly limited, but is preferably 2 or more, more preferably 2 to 10, and even more preferably 3 to 6.
Rt is preferably an alkylene group having 1 to 5 carbon atoms, and more preferably a -CH ₂ - group, a -(CH ₂ ) ₂ - group, or a -(CH ₂ ) ₃ - group.

_Lc1 is particularly preferably an arylene group, an alkylene group, or a single bond, and most preferably a phenylene group or a single bond.

In general formula (cN1), A _c1 represents a group which is decomposed by the action of an acid.
The group that is decomposed by the action of an acid preferably has a structure in which a polar group is protected with a group that is eliminated by the action of an acid (a leaving group).

Examples of the polar group include the polar groups described in the repeating unit having an acid-decomposable group of the above-mentioned resin (A). Among them, a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), or a sulfonic acid group is preferred, and a carboxyl group or a phenolic hydroxyl group is more preferred.
Examples of the group that is eliminated by the action of an acid include the groups represented by the formulae (Y1) to (Y4) described in the above resin (A).

In general formula (cN1), nc represents an integer from 1 to 5. nc is preferably an integer from 1 to 3.

In general formula (cN1), Xc represents an (n+1)-valent linking group.
Xc is preferably an aromatic ring group, more preferably an aromatic ring group having 6 to 20 carbon atoms, and further preferably a benzene ring group.

The anion represented by the above general formula (cN1) is more preferably an anion represented by the following general formula (cN2).

In general formula (cN2), L _c1 , A _c1 and nc have the same meanings as L _c1 , A _c1 and nc in general formula (cN1) described above, and preferred examples are also the same.

Specific examples of the counter anion A ₁ ^- of the compound represented by formula (B-1) are shown below, but the present invention is not limited thereto.

The compound represented by general formula (B-1) can be synthesized by referring to known methods, for example, the methods described in Chem. Lett. 1994, 23, 1827-1828 and J. Am. Chem. Soc. 2001, 123, 3852-3853. Specific synthesis examples are shown in the examples described later.

In the general formula (B-2), Rb ₅ to Rb ₁₂ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a thiol group, an alkylthio group, an arylthio group, an amino group, a carbonyl group, a hydroxyl group, a cyano group, or a group consisting of a combination thereof. _{Rb 13} represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group. X represents -S-, -O-, or -NRb ₁₄ -. Rb ₁₄ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group. Rb ₅ to Rb ₁₄ may be bonded to each other to form a ring. A ₂ ^- represents a counter anion.

Examples of the alkyl group, alkenyl group, alkynyl group, aryl group, alkoxy group, alkylthio group, arylthio group, and groups consisting of combinations thereof represented by _Rb5 to _Rb12 include the alkyl group, alkenyl group, alkynyl group, aryl group, alkoxy group, alkylthio group, arylthio group, and groups consisting of combinations thereof represented by _Rb1 to _Rb4 described above, and preferred examples are also the same.

The above groups represented by Rb ₅ to Rb ₁₂ may further have a substituent. Examples of the further substituent include the groups described above as Rb ₁ to Rb ₄ .

Examples of the alkyl group, alkenyl group, alkynyl group, and aryl group represented by _Rb13 include the alkyl group, alkenyl group, alkynyl group, and aryl group represented by _Rb1 to _Rb4 described above, and preferred examples are also the same.

The above group represented by Rb ₁₃ may further have a substituent. Examples of the further substituent include each of the groups as Rb ₁ to Rb ₄ described above.

X represents -S-, -O-, or -NRb ₁₄ -, where Rb ₁₄ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group.
Examples of the alkyl group, alkenyl group, alkynyl group, and aryl group represented by Rb ₁₄ include the alkyl group, alkenyl group, alkynyl group, and aryl group represented by Rb ₁ to Rb ₄ described above, and preferred examples are also the same.

Rb ₅ to Rb ₁₄ may be bonded to each other to form a ring.
The ring formed by bonding Rb ₅ to Rb ₁₄ to each other may be a monocyclic ring or a polycyclic ring, and may be an aromatic ring or a non-aromatic ring.

The aromatic ring may be an aromatic hydrocarbon ring or an aromatic hetero ring.
The aromatic hydrocarbon ring is preferably a benzene ring.
The aromatic heterocycle is preferably an aromatic heterocycle containing at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom, and examples thereof include a thiophene ring, a furan ring, a pyrrole ring, an oxazole ring, a thiazole ring, an imidazole ring, a pyridine ring, an isothiazole ring, and a thiadiazole ring.

The non-aromatic ring may be an aliphatic hydrocarbon ring or an aliphatic hetero ring.
Examples of the aliphatic hydrocarbon ring include cycloalkane rings such as a cyclohexane ring, and cycloalkene rings such as a cyclohexene ring.
The aliphatic heterocycle is preferably an aliphatic heterocycle containing at least one heteroatom selected from the group consisting of a sulfur atom, a nitrogen atom, and an oxygen atom, and examples thereof include rings in which a methylene group contained in the above-mentioned aliphatic hydrocarbon ring is substituted with a group containing a heteroatom such as -O-, -S-, -S(=O) _2- , or -C(=O)-.

The ring formed by bonding Rb ₅ to Rb ₁₄ together may further have a substituent. Examples of the further substituent include the groups described above for Rb ₁ to Rb ₄ .

Specific examples of the cation moiety having a cation radical structure of the compound represented by general formula (B-2) are shown below, but the present invention is not limited to these. In the formula, Me represents a methyl group.

A ₂ ^- represents a counter anion. Examples of the counter anion represented by A ₂ ^- include the counter anions represented by A ₁ ^- described above, and preferred examples are also the same.

The compound represented by general formula (B-2) can be synthesized by referring to known methods. Specific synthesis examples are shown in the examples described below.

The salt (B) is typically a compound having a cation radical structure and a counter anion. Examples of the counter anion include the counter anions represented by A ₁ ^- described above, and preferred examples thereof are also the same.
The salt (B) preferably has a carboxylate anion or a sulfonate anion as a counter anion.
It is preferable that A ₁ ⁻ in the above general formula (B-1) or A ₂ ⁻ in the above general formula (B-2) is represented by any one of the above general formulas (AN1) to (AN3).

In the composition of the present invention, the content of the salt (B) is preferably from 0.1 to 40.0 mass%, more preferably from 1.0 to 25.0 mass%, and particularly preferably from 1.0 to 15.0 mass%, based on the total solid content of the composition of the present invention.
In the composition of the present invention, the salt (B) may be used alone or in combination of two or more. When two or more types are used, it is preferable that the total content is within the above-mentioned suitable content range.

[Compound (C) that generates an acid upon exposure to actinic rays or radiation]
The composition of the present invention preferably contains a compound (photoacid generator) that generates an acid upon exposure to actinic rays or radiation.
The photoacid generator may be in the form of a low molecular weight compound, or may be incorporated into a part of a polymer. In addition, the photoacid generator may be in the form of a low molecular weight compound and in the form of a polymer in combination.
When the photoacid generator is in the form of a low molecular weight compound, the molecular weight of the photoacid generator is preferably 3000 or less, more preferably 2000 or less, and even more preferably 1000 or less. There is no particular lower limit, but a molecular weight of 100 or more is preferable.
When the photoacid generator is in a form in which it is incorporated into a part of a polymer, it may be incorporated into a part of the resin (A) or into a resin different from the resin (A).
The photoacid generator is preferably in the form of a low molecular weight compound.
The photoacid generator is preferably a compound that generates an acid having a pKa of −2.0 or more upon irradiation with actinic rays or radiation, and more preferably a compound that generates an acid having a pKa of −2.0 or more and 1.0 or less.

Examples of photoacid generators include compounds (onium salts) represented by "M ⁺ X ^- ", and are preferably compounds that generate an organic acid upon exposure to light.
Examples of the organic acid include sulfonic acids (aliphatic sulfonic acids, aromatic sulfonic acids, camphorsulfonic acids, etc.), carboxylic acids (aliphatic carboxylic acids, aromatic carboxylic acids, aralkyl carboxylic acids, etc.), carbonylsulfonylimide acids, bis(alkylsulfonyl)imide acids, and tris(alkylsulfonyl)methide acids.

In the compound represented by "M ⁺ X ^- ", M ⁺ represents an organic cation.
The organic cation is not particularly limited, and the valence of the organic cation may be monovalent or divalent or higher.
Among them, the organic cation is preferably a cation represented by formula (ZaI) (hereinafter also referred to as "cation (ZaI)") or a cation represented by formula (ZaII) (hereinafter also referred to as "cation (ZaII)").

In the above formula (ZaI), R ²⁰¹ , R ²⁰² and R ²⁰³ each independently represent an organic group.
The number of carbon atoms in the organic group represented by R ²⁰¹ , R ²⁰² , and R ²⁰³ is preferably 1 to 30, and more preferably 1 to 20. Any two of R ²⁰¹ to R ²⁰³ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester group, an amide group, or a carbonyl group. Examples of the group formed by bonding any two of R ²⁰¹ to R ²⁰³ include an alkylene group (e.g., a butylene group and a pentylene group) and -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -.

Suitable embodiments of the organic cation in formula (ZaI) include cation (ZaI-1), cation (ZaI-2), cation (ZaI-3b), and cation (ZaI-4b), which will be described later.

First, the cation (ZaI-1) will be described.
The cation (ZaI-1) is an arylsulfonium cation in which at least one of R ²⁰¹ to R ²⁰³ in the above formula (ZaI) is an aryl group.
In the arylsulfonium cation, all of R ²⁰¹ to R ²⁰³ may be aryl groups, or some of R ²⁰¹ to R ²⁰³ may be aryl groups, with the remainder being alkyl groups or cycloalkyl groups.
One of R ²⁰¹ to R ²⁰³ may be an aryl group, and the remaining two of R ²⁰¹ to R ²⁰³ may be bonded to form a ring structure, which may contain an oxygen atom, a sulfur atom, an ester group, an amide group, or a carbonyl group in the ring. Examples of the group formed by bonding two of R ²⁰¹ to R ²⁰³ include alkylene groups in which one or more methylene groups may be substituted with oxygen atoms, sulfur atoms, ester groups, amide groups, and/or carbonyl groups (e.g., butylene group, pentylene group, and -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -).
Arylsulfonium cations include triarylsulfonium cations, diarylalkylsulfonium cations, aryldialkylsulfonium cations, diarylcycloalkylsulfonium cations, and aryldicycloalkylsulfonium cations.

The aryl group contained in the arylsulfonium cation is preferably a phenyl group or a naphthyl group, more preferably a phenyl group.The aryl group may be an aryl group having a heterocyclic structure with an oxygen atom, a nitrogen atom, or a sulfur atom.The heterocyclic structure may include a pyrrole residue, a furan residue, a thiophene residue, an indole residue, a benzofuran residue, and a benzothiophene residue.When the arylsulfonium cation has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group or cycloalkyl group which the arylsulfonium cation optionally has 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, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, or a cyclohexyl group.

Preferred substituents that the aryl group, alkyl group, and cycloalkyl group of R ²⁰¹ to R ²⁰³ may have are alkyl groups (e.g., 1 to 15 carbon atoms), cycloalkyl groups (e.g., 3 to 15 carbon atoms), aryl groups (e.g., 6 to 14 carbon atoms), alkoxy groups (e.g., 1 to 15 carbon atoms), cycloalkylalkoxy groups (e.g., 1 to 15 carbon atoms), halogen atoms (e.g., fluorine and iodine), hydroxyl groups, carboxyl groups, ester groups, sulfinyl groups, sulfonyl groups, alkylthio groups, or phenylthio groups.
The above-mentioned substituent may further have a substituent if possible, and it is also preferable that the above-mentioned alkyl group has a halogen atom as a substituent to form a halogenated alkyl group such as a trifluoromethyl group.
It is also preferred that the above-mentioned substituents are combined in any desired manner to form an acid-decomposable group.
The acid-decomposable group is intended to be a group that is decomposed by the action of an acid to generate a polar group, and is preferably a structure in which the polar group is protected by a group that is eliminated by the action of an acid. The polar group and the elimination group are as described above.

Next, the cation (ZaI-2) will be described.
The cation (ZaI-2) is a cation in which R ²⁰¹ to R ²⁰³ in formula (ZaI) each independently represent an organic group not having an aromatic ring. The aromatic ring also includes an aromatic ring containing a heteroatom.
The organic group not having an aromatic ring represented by R ²⁰¹ to R ²⁰³ preferably has 1 to 30 carbon atoms, and more preferably 1 to 20 carbon atoms.
R ²⁰¹ to R ²⁰³ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, a 2-oxocycloalkyl group, or an alkoxycarbonylmethyl group, and still more preferably a linear or branched 2-oxoalkyl group.

Examples of the alkyl group and cycloalkyl group of R ²⁰¹ to R ²⁰³ include linear alkyl groups having 1 to 10 carbon atoms or branched alkyl groups having 3 to 10 carbon atoms (e.g., methyl, ethyl, propyl, butyl, and pentyl groups), and cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, and norbornyl groups).
R ²⁰¹ to R ²⁰³ may be further substituted with a halogen atom, an alkoxy group (eg, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.
It is also preferred that the substituents of R ²⁰¹ to R ²⁰³ each independently form an acid-decomposable group through any combination of the substituents.

Next, the cation (ZaI-3b) will be described.
The cation (ZaI-3b) is a cation represented by the following formula (ZaI-3b).

In formula (ZaI-3b), R _1c to R _5c each independently represent 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.
R _6c and R _7c each independently represent a hydrogen atom, an alkyl group (eg, a t-butyl group), a cycloalkyl group, a halogen atom, a cyano group, or an aryl group.
R _x and R _y each independently represent an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, an allyl group, or a vinyl group.
It is also preferred that the substituents of R _1c to R _7c and R _x and R _y each independently form an acid-decomposable group through any combination of the substituents.

Any two or more of R _1c to R _5c , R _5c and R _6c , R _6c and R _7c , R _5c and R _x , and R _x and R _y 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 ring include an aromatic or non-aromatic hydrocarbon ring, an aromatic or non-aromatic heterocycle, and a polycyclic condensed ring formed by combining two or more of these rings. Examples of the ring include a 3- to 10-membered ring, preferably a 4- to 8-membered ring, and more preferably a 5- or 6-membered ring.

The group formed by combining any two or more of R _1c to R _5c , R _6c and R _7c , and R _x and R _y includes alkylene groups such as butylene and pentylene, in which the methylene group may be substituted with a heteroatom such as an oxygen atom.
The groups formed by combining _R5c and _R6c , and _R5c and _Rx are preferably a single bond or an alkylene group. Examples of the alkylene group include a methylene group and an ethylene group.

R _1c to R _5c , R _6c , R _7c , R _x , R _y , and any two or more of R _1c to R _5c , R _5c and R _6c , R _6c and R _7c , R _5c and R _x , and R _x and R _y may each have a substituent.

Next, the cation (ZaI-4b) will be described.
The cation (ZaI-4b) is a cation represented by the following formula (ZaI-4b).

In formula (ZaI-4b), l represents an integer of 0 to 2; r represents an integer of 0 to 8.
R ₁₃ represents a hydrogen atom, a halogen atom (e.g., a fluorine atom, an iodine atom, etc.), a hydroxyl group, an alkyl group, a halogenated alkyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, or a group containing a cycloalkyl group (which may be a cycloalkyl group itself or a group containing a cycloalkyl group as a part). These groups may have a substituent.
R ₁₄ represents a hydroxyl group, a halogen atom (e.g., a fluorine atom and an iodine atom, etc.), an alkyl group, a halogenated alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, a cycloalkylsulfonyl group, or a group containing a cycloalkyl group (may be a cycloalkyl group itself or a group containing a cycloalkyl group as a part). These groups may have a substituent. When there are a plurality of R ₁₄ , each independently represents the above group such as a hydroxyl group.
Each R ₁₅ independently represents an alkyl group, a cycloalkyl group, or a naphthyl group. Two R ₁₅ may be bonded to each other to form a ring. When two R ₁₅ are bonded to each other to form a ring, the ring skeleton may contain a heteroatom such as an oxygen atom or a nitrogen atom.
In one embodiment, it is preferable that two R ₁₅ are alkylene groups and are bonded to each other to form a ring structure. The alkyl group, the cycloalkyl group, the naphthyl group, and the ring formed by bonding two R ₁₅ to each other may have a substituent.

In formula (ZaI-4b), the alkyl groups of R ₁₃ , R ₁₄ and R ₁₅ may be linear or branched. The number of carbon atoms in the alkyl group is preferably 1 to 10. The alkyl group is preferably a methyl group, an ethyl group, an n-butyl group, a t-butyl group or the like.
It is also preferred that each of the substituents R ₁₃ to R ₁₅ and R _x and R _y independently form an acid-decomposable group through any combination of the substituents.

Next, formula (ZaII) will be described.
In formula (ZaII), R ²⁰⁴ and R ²⁰⁵ each independently represent an aryl group, an alkyl group or a cycloalkyl group.
The aryl group of R ²⁰⁴ and R ²⁰⁵ is preferably a phenyl group or a naphthyl group, more preferably a phenyl group. The aryl group of R ²⁰⁴ and R ²⁰⁵ may be an aryl group having a heterocycle with an oxygen atom, a nitrogen atom, or a sulfur atom. Examples of the skeleton of the aryl group having a heterocycle include pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene.
The alkyl group and cycloalkyl group of R ²⁰⁴ and R ²⁰⁵ are preferably a linear alkyl group having 1 to 10 carbon atoms or a branched alkyl group having 3 to 10 carbon atoms (e.g., a methyl group, an ethyl group, a propyl group, a butyl group, or a pentyl group), or a cycloalkyl group having 3 to 10 carbon atoms (e.g., a cyclopentyl group, a cyclohexyl group, or a norbornyl group).

The aryl group, alkyl group, and cycloalkyl group of R ²⁰⁴ and R ²⁰⁵ may each independently have a substituent. Examples of the substituent that the aryl group, alkyl group, and cycloalkyl group of R ²⁰⁴ and R ²⁰⁵ may have include an alkyl group (e.g., having 1 to 15 carbon atoms), a cycloalkyl group (e.g., having 3 to 15 carbon atoms), an aryl group (e.g., having 6 to 15 carbon atoms), an alkoxy group (e.g., having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group. It is also preferable that the substituents of R ²⁰⁴ and R ²⁰⁵ each independently form an acid-decomposable group by any combination of the substituents.

Specific examples of organic cations are shown below, but the present invention is not limited to these.

In the compound represented by "M ⁺ X ^- ", X ^- represents an organic anion.
The organic anion is not particularly limited, and examples thereof include monovalent or divalent or higher organic anions.
As the organic anion, anions having a significantly low ability to cause a nucleophilic reaction are preferred, and non-nucleophilic anions are more preferred.

Examples of non-nucleophilic anions include sulfonate anions (aliphatic sulfonate anions, aromatic sulfonate anions, camphorsulfonate anions, etc.), carboxylate anions (aliphatic carboxylate anions, aromatic carboxylate anions, aralkyl carboxylate anions, etc.), sulfonylimide anions, bis(alkylsulfonyl)imide anions, and tris(alkylsulfonyl)methide anions.

The aliphatic moiety in the aliphatic sulfonate anion and the aliphatic carboxylate anion may be a linear or branched alkyl group or a cycloalkyl group, and is preferably a linear or branched alkyl group having 1 to 30 carbon atoms or a cycloalkyl group having 3 to 30 carbon atoms.
The alkyl group may be, for example, a fluoroalkyl group (which may have a substituent other than a fluorine atom, or may be a perfluoroalkyl group).

The aryl group in the aromatic sulfonate anion and aromatic carboxylate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

The alkyl group, cycloalkyl group, and aryl group listed above may have a substituent. The substituent is not particularly limited, but examples include a nitro group, a halogen atom such as a fluorine atom or a chlorine atom, a carboxyl group, a hydroxyl group, an amino group, a cyano group, an alkoxy group (preferably having 1 to 15 carbon atoms), an alkyl group (preferably having 1 to 10 carbon atoms), a cycloalkyl group (preferably having 3 to 15 carbon atoms), an aryl group (preferably having 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably having 2 to 7 carbon atoms), an acyl group (preferably having 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably having 2 to 7 carbon atoms), an alkylthio group (preferably having 1 to 15 carbon atoms), an alkylsulfonyl group (preferably having 1 to 15 carbon atoms), an alkyliminosulfonyl group (preferably having 1 to 15 carbon atoms), and an aryloxysulfonyl group (preferably having 6 to 20 carbon atoms).

The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 7 to 14 carbon atoms.
Examples of the aralkyl group having 7 to 14 carbon atoms include a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylbutyl group.

An example of a sulfonylimide anion is the saccharin anion.

The alkyl group in the bis(alkylsulfonyl)imide anion and the tris(alkylsulfonyl)methide anion is preferably an alkyl group having 1 to 5 carbon atoms. Examples of the substituent on these alkyl groups include a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, an alkylthio group, an alkyloxysulfonyl group, an aryloxysulfonyl group, and a cycloalkylaryloxysulfonyl group, and a fluorine atom or an alkyl group substituted with a fluorine atom is preferred.
In addition, the alkyl groups in the bis(alkylsulfonyl)imide anion may be bonded to each other to form a ring structure, which increases the acid strength.

Other non-nucleophilic anions include, for example, phosphorus fluorides (eg, PF ₆ ⁻ ), boron fluorides (eg, BF ₄ ⁻ ), and antimony fluorides (eg, SbF ₆ ⁻ ).

Preferred non-nucleophilic anions are aliphatic sulfonate anions in which at least the α-position of the sulfonic acid is substituted with a fluorine atom, aromatic sulfonate anions substituted with a fluorine atom or a group having a fluorine atom, bis(alkylsulfonyl)imide anions in which an alkyl group is substituted with a fluorine atom, or tris(alkylsulfonyl)methide anions in which an alkyl group is substituted with a fluorine atom. Among these, perfluoroaliphatic sulfonate anions (preferably having 4 to 8 carbon atoms) or benzenesulfonate anions having a fluorine atom are more preferable, and nonafluorobutanesulfonate anions, perfluorooctanesulfonate anions, pentafluorobenzenesulfonate anions, or 3,5-bis(trifluoromethyl)benzenesulfonate anions are even more preferable.

As the non-nucleophilic anion, among the anions represented by the above general formulae (AN1) to (AN3), anions corresponding to a sulfonate anion, i.e., an anion in which A _Q1 ^- in general formula (AN1) is a sulfonate anion, an anion in which A _Q2 ^- in general formula (AN2) is a sulfonate anion, and an anion in which A _Q3 ^- in general formula (AN3) is a sulfonate anion are also preferred.

The non-nucleophilic anion is also preferably a disulfonamide anion.
An example of a disulfonamide anion is an anion represented by N ⁻ (SO ₂ —R ^q ) ₂ .
Here, R ^q represents an alkyl group which may have a substituent, preferably a fluoroalkyl group, more preferably a perfluoroalkyl group. Two R ^q may be bonded to each other to form a ring. The group formed by bonding two R ^q to each other is preferably an alkylene group which may have a substituent, preferably a fluoroalkylene group, more preferably a perfluoroalkylene group. The number of carbon atoms of the alkylene group is preferably 2 to 4.

Furthermore, examples of non-nucleophilic anions include the anions represented by the above formulas (d1-1) to (d1-4).

The organic anion may be used alone or in combination of two or more. Preferred examples include the organic anions given as specific examples of the counter ion A ₁ ^- in the compound represented by general formula (B-1) as the salt (B) and the counter ion A ₂ ^- in the compound represented by general formula (B-2).

From the viewpoint of suppressing development defects, the composition of the present invention preferably contains a salt (C) having a group that decomposes under the action of an acid, and more preferably contains a compound represented by the following general formula (c1) as a photoacid generator.

In general formula (c1),
L represents a single bond or a divalent linking group. When a plurality of L's are present, the plurality of L's may be the same or different.
A represents a group which is decomposed by the action of an acid. When a plurality of As are present, the plurality of As may be the same or different.
n c represents an integer of 1 to 5.
Xc represents an (n+1)-valent linking group.
Mc ⁺ represents a sulfonium ion or an iodonium ion.

L, A, nc, and Xc in formula (c1) have the same meanings as L _c1 , A _c1 , nc, and Xc in formula (cN1) above, and preferred examples are also the same.

In the general formula (c1), Mc ⁺ represents a sulfonium ion or an iodonium ion. Examples of the sulfonium ion and the iodonium ion include the cations represented by the above formula (ZaI) and formula (ZaII), and among these, the above cations (ZaI-1), (ZaI-2), (ZaI-3b), and (ZaI-4b) are preferred.

The compound represented by the above general formula (c1) is more preferably a compound represented by the following general formula (c2):

In the general formula (c2), L, A, nc, and Mc ⁺ have the same meanings as L, A, nc, and Mc ⁺ in the general formula (c1), and preferred examples thereof are also the same.

Specific examples of compounds represented by general formula (c1) are shown below, but are not limited to these.

It is also preferable that the photoacid generator is at least one selected from the group consisting of compounds (I) to (II).

(Compound (I))
Compound (I) is a compound having one or more structural moieties X and one or more structural moieties Y, which generates an acid containing a first acidic moiety derived from the structural moiety X and a second acidic moiety derived from the structural moiety Y when irradiated with actinic rays or radiation:
Structural moiety X: a structural moiety consisting of an anionic moiety A ₁ ^- and a cationic moiety M ₁ ⁺ , which forms a first acidic moiety represented by HA ₁ when irradiated with actinic rays or radiation. Structural moiety Y: a structural moiety consisting of an anionic moiety A ₂ ^- and a cationic moiety M ₂ ⁺ , which forms a second acidic moiety represented by HA ₂ when irradiated with actinic rays or radiation. The compound (I) satisfies the following condition I.

Condition I: Compound PI, which is obtained by replacing the cationic moiety M ₁ ⁺ in the structural moiety X and the cationic moiety M ₂ ⁺ in the structural moiety Y in compound (I) with H ⁺ , has an acid dissociation constant a1 derived from the acidic moiety represented by HA ₁ , which is obtained by replacing the cationic moiety M ₁ ⁺ in the structural moiety X with H ⁺ , and an acid dissociation constant a2 derived from the acidic moiety represented by HA ₂ , which is obtained by replacing the cationic moiety M ₂ ⁺ in the structural moiety Y with H ⁺ , and the acid dissociation constant a2 is greater than the acid dissociation constant a1.

Examples of the compound (I) include the compound (I) described in paragraphs [0176] to [0280] of WO 2022/024928.

(Compound (II))
Compound (II) is a compound having two or more of the above structural moieties X and one or more of the following structural moieties Z, and is a compound that generates an acid containing two or more of the first acidic moieties derived from the structural moiety X and the structural moiety Z when irradiated with actinic rays or radiation.
Structural moiety Z: a non-ionic moiety capable of neutralizing an acid

Examples of the compound (II) include the compound (II) described in paragraphs [0176] to [0280] of WO 2022/024928.

The content of the photoacid generator is not particularly limited, but is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, based on the total solid content of the composition of the present invention, in order to make the cross-sectional shape of the pattern to be formed more rectangular. The content is preferably 50.0% by mass or less, more preferably 30.0% by mass or less, and even more preferably 25.0% by mass or less, based on the total solid content of the composition of the present invention.
The photoacid generator may be used alone or in combination of two or more kinds.

[Acid Diffusion Controller (D)]
The composition of the present invention may further comprise an acid diffusion controller (D) different from the above-mentioned salt (B).
The acid diffusion controller (D) functions as a quencher that traps the acid generated from the photoacid generator or the like upon exposure and suppresses the reaction of the acid-decomposable resin in the unexposed areas caused by excess acid generated.
The type of the acid diffusion controller (D) is not particularly limited, and examples thereof include a basic compound (DA), a low molecular weight compound (DB) having a nitrogen atom and a group that is eliminated by the action of an acid, and a compound (DC) whose acid diffusion control ability is reduced or lost by irradiation with actinic rays or radiation.
Examples of the compound (DC) include an onium salt compound (DD) of an acid that is weaker than the acid generated from a photoacid generator (e.g., the salt (C)), and a basic compound (DE) whose basicity is reduced or lost by irradiation with actinic rays or radiation.
Specific examples of the basic compound (DA) include those described in paragraphs [0132] to [0136] of WO 2020/066824, and specific examples of the low molecular weight compound (DB) having a nitrogen atom and a group that is eliminated by the action of an acid include those described in paragraphs [0156] to [0163] of WO 2020/066824.
Specific examples of onium salt compounds (DD) that are relatively weakly acidic relative to the photoacid generator include those described in paragraphs [0305] to [0314] of WO 2020/158337, and specific examples of basic compounds (DE) whose basicity is reduced or eliminated by irradiation with actinic rays or radiation include those described in paragraphs [0137] to [0155] of WO 2020/066824, and those described in paragraph [0164] of WO 2020/066824.

In addition to the above, for example, known compounds disclosed in U.S. Patent Application Publication No. 2016/0070167A1, paragraphs [0627] to [0664], U.S. Patent Application Publication No. 2015/0004544A1, paragraphs [0095] to [0187], U.S. Patent Application Publication No. 2016/0237190A1, paragraphs [0403] to [0423], and U.S. Patent Application Publication No. 2016/0274458A1, paragraphs [0259] to [0328] can be suitably used as acid diffusion control agents.

In the case where the composition of the present invention contains an acid diffusion controller (D), the content of the acid diffusion controller (D) is preferably 0.1 to 15.0 mass %, more preferably 0.5 to 15.0 mass %, based on the total solid content of the composition of the present invention.
The acid diffusion controller (D) may be used alone or in combination of two or more. When two or more types are used, the total content is preferably within the above-mentioned preferred content range.

[Hydrophobic resin]
The composition of the present invention may further contain a hydrophobic resin different from the resin (A).
The hydrophobic resin is preferably designed to be unevenly distributed on the surface of the resist film, but unlike a surfactant, it does not necessarily have to have a hydrophilic group in the molecule, and does not necessarily have to contribute to uniform mixing of polar and non-polar substances.
The effects of adding a hydrophobic resin include control of the static and dynamic contact angle of water on the resist film surface, and suppression of outgassing.

From the viewpoint of uneven distribution on the surface layer of the film, the hydrophobic resin preferably has at least one of fluorine atoms, silicon atoms, and _CH3 partial structures contained in the side chain portion of the resin, more preferably has at least two of them. 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 may be substituted on the side chain.
Examples of hydrophobic resins include the compounds described in paragraphs [0275] to [0279] of WO 2020/004306.

When the composition of the present invention contains a hydrophobic resin, the content of the hydrophobic resin is preferably from 0.01 to 20.0 mass %, more preferably from 0.1 to 15.0 mass %, based on the total solid content of the composition of the present invention.
The hydrophobic resin may be used alone or in combination of two or more. When two or more types are used, the total content is preferably within the above-mentioned preferred content range.

[Surfactant]
The composition of the present invention may contain a surfactant. When the composition contains a surfactant, a pattern having better adhesion and fewer development defects can be formed.
The surfactant is preferably a fluorine-based and/or silicon-based surfactant.
Examples of fluorine-based and/or silicone-based surfactants include the surfactants disclosed in paragraphs [0218] and [0219] of WO 2018/193954.

When the composition of the present invention contains a surfactant, the content of the surfactant is preferably from 0.0001 to 2.0 mass%, more preferably from 0.0005 to 1.0 mass%, and still more preferably from 0.1 to 1.0 mass%, based on the total solid content of the composition of the present invention.
The surfactant may be used alone or in combination of two or more. When two or more surfactants are used, the total content is preferably within the above-mentioned preferred content range.

〔solvent〕
The composition of the present invention preferably contains a solvent.
The solvent preferably contains (M1) propylene glycol monoalkyl ether carboxylate and (M2) at least one selected from the group consisting of propylene glycol monoalkyl ether, lactate ester, acetate ester, alkoxypropionate ester, linear ketone, cyclic ketone, lactone, and alkylene carbonate. The solvent may further contain components other than the components (M1) and (M2).

The combination of the above-mentioned solvent and the above-mentioned resin is preferable from the viewpoint of improving the coatability of the composition of the present invention and reducing the number of development defects of the pattern. The above-mentioned solvent has a good balance of the solubility, boiling point, and viscosity of the above-mentioned resin, so that it is possible to suppress unevenness in the thickness of the resist film and the occurrence of precipitates during spin coating.
Details of the components (M1) and (M2) are described in paragraphs [0218] to [0226] of WO 2020/004306, the contents of which are incorporated herein by reference.

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 mass % based on the total amount of the solvent.

The content of the solvent in the composition of the present invention is preferably determined so that the solids concentration is 0.5 to 30 mass %, and more preferably 1 to 20 mass %. This further improves the applicability of the composition of the present invention.

[Other additives]
The composition of the present invention may further contain a dissolution inhibiting compound, a dye, a plasticizer, a photosensitizer, a light absorber, and/or a compound that promotes solubility in a developer (for example, a phenol compound having a molecular weight of 1000 or less, or an alicyclic or aliphatic compound containing a carboxyl group).

The above-mentioned "dissolution-blocking compound" is a compound with a molecular weight of 3000 or less that decomposes under the action of acid and reduces its solubility in an organic developer.

The composition of the present invention is suitably used as a photosensitive composition for EB or EUV exposure.
EUV light has a wavelength of 13.5 nm, which is shorter than ArF light (wavelength 193 nm) and the like, and therefore the number of incident photons is smaller when exposed at the same sensitivity. Therefore, the effect of "photon shot noise," in which the number of photons varies stochastically, is large, leading to deterioration of line edge roughness (LER) and bridge defects. One method of reducing photon shot noise is to increase the exposure dose to increase the number of incident photons, but this is a trade-off with the demand for higher sensitivity.

When the value A calculated by the following formula (1) is high, the resist film formed from the resist composition has high absorption efficiency of EUV light and electron beams, which is effective in reducing photon shot noise. The value A represents the absorption efficiency of EUV light and electron beams by mass proportion of the resist film.
Formula (1): A = ([H] x 0.04 + [C] x 1.0 + [N] x 2.1 + [O] x 3.6 + [F] x 5.6 + [S] x 1.5 + [I] x 39.5) / ([H] x 1 + [C] x 12 + [N] x 14 + [O] x 16 + [F] x 19 + [S] x 32 + [I] x 127)
The value A is preferably 0.120 or more. Although there is no particular upper limit, if the value A is too large, the EUV light and electron beam transmittance of the resist film decreases, and the optical image profile in the resist film deteriorates, making it difficult to obtain a good pattern shape, so the value A is preferably 0.240 or less, and more preferably 0.220 or less.

In formula (1), [H] represents the molar ratio of hydrogen atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition, [C] represents the molar ratio of carbon atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition, [N] represents the molar ratio of nitrogen atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition, and [O] represents the molar ratio of nitrogen atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition. [F] represents the molar ratio of fluorine atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition, [S] represents the molar ratio of sulfur atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition, and [I] represents the molar ratio of iodine atoms derived from all solids to all atoms in all solids in the actinic ray-sensitive or radiation-sensitive resin composition.
For example, when a resist composition contains an acid-decomposable resin, a photoacid generator, an acid diffusion controller, and a solvent, the acid-decomposable resin, the photoacid generator, and the acid diffusion controller correspond to the solid content. In other words, the total atoms of the total solid content corresponds to the sum of all atoms derived from the resin, all atoms derived from the photoacid generator, and all atoms derived from the acid diffusion controller.
For example, [H] represents the molar ratio of hydrogen atoms derived from all solids to all atoms in the total solids. Based on the above example, [H] represents the molar ratio of the sum of hydrogen atoms derived from the acid-decomposable resin, the hydrogen atoms derived from the photoacid generator, and the hydrogen atoms derived from the acid diffusion controller to the sum of all atoms derived from the acid-decomposable resin, the photoacid generator, and the acid diffusion controller.

The A value can be calculated by calculating the ratio of the numbers of atoms contained when the structure and content of all solid components in the resist composition are known. Even if the components are unknown, the ratio of the numbers of atoms contained can be calculated by analytical methods such as elemental analysis of the resist film obtained by evaporating the solvent components of the resist composition.

[Actinic ray- or radiation-sensitive film, pattern formation method]
The present invention also relates to an actinic ray- or radiation-sensitive film formed from the composition of the present invention. The actinic ray- or radiation-sensitive film of the present invention is preferably a resist film.
The procedure for the pattern formation method using the composition of the present invention is not particularly limited, but it is preferable that the method comprises the following steps.
Step 1: forming an actinic ray-sensitive or radiation-sensitive film on a substrate using the composition of the present invention; Step 2: exposing the actinic ray-sensitive or radiation-sensitive film; Step 3: developing the exposed actinic ray-sensitive or radiation-sensitive film using a developer. The procedure of each of the above steps will be described in detail below.

(Step 1: Actinic Ray- or Radiation-Sensitive Film Forming Step)
Step 1 is a step of forming an actinic ray- or radiation-sensitive film on a substrate using the composition of the present invention.

An example of a method for forming an actinic ray- or radiation-sensitive film on a substrate using the composition of the present invention is a method in which the composition of the present invention is coated on a substrate.
The composition of the present invention is preferably filtered as necessary before application. The pore size of the filter is preferably 0.1 μm or less, more preferably 0.05 μm or less, and even more preferably 0.03 μm or less. The filter is preferably made of polytetrafluoroethylene, polyethylene, or nylon.

The composition of the present invention can be applied by a suitable application method such as a spinner or coater onto a substrate (e.g., silicon, silicon dioxide-coated) such as those used in the manufacture of integrated circuit elements. The application method is preferably spin coating using a spinner. The rotation speed when spin coating using a spinner is preferably 1000 to 3000 rpm (rotations per minute).
After coating the composition of the present invention, the substrate may be dried to form an actinic ray-sensitive or radiation-sensitive film. If necessary, various undercoats (inorganic films, organic films, anti-reflection films) may be formed under the actinic ray-sensitive or radiation-sensitive film.

The drying method may be, for example, a method of drying by heating. Heating can be performed by a means provided in a normal exposure machine and/or a developing machine, and may also be performed using a hot plate or the like. The heating temperature is preferably 80 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 130°C. The heating time is preferably 30 to 1000 seconds, more preferably 60 to 800 seconds, and even more preferably 60 to 600 seconds.

The thickness of the actinic ray-sensitive or radiation-sensitive film is not particularly limited, but is preferably 10 to 120 nm, since it allows for the formation of fine patterns with higher precision. In particular, when EUV exposure is used, the thickness of the actinic ray-sensitive or radiation-sensitive 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 actinic ray-sensitive or radiation-sensitive film is more preferably 10 to 120 nm, and even more preferably 15 to 90 nm.

A top coat may be formed on the actinic ray-sensitive or radiation-sensitive film by using a top coat composition.
It is preferable that the top coat composition does not mix with the actinic ray-sensitive or radiation-sensitive film and can be uniformly applied to the upper layer of the resist film. The top coat is not particularly limited, and a conventionally known top coat can be formed by a conventionally known method, for example, a top coat can be formed based on the description in paragraphs [0072] to [0082] of JP2014-059543A.
For example, it is preferable to form a top coat containing a basic compound such as that described in JP 2013-61648 A on an actinic ray-sensitive or radiation-sensitive film. Specific examples of the basic compound that the top coat may contain include the basic compounds that may be contained in the composition of the present invention.
It is also preferred that the top coat contains a compound containing at least one group or bond selected from the group consisting of an ether bond, a thioether bond, a hydroxyl group, a thiol group, a carbonyl bond, and an ester bond.

(Step 2: Exposure step)
Step 2 is a step of exposing the actinic ray- or radiation-sensitive film to light.
The exposure method may be a method in which the formed actinic ray-sensitive or radiation-sensitive film is irradiated with actinic rays or radiation through a predetermined mask.
Examples of the actinic ray or radiation include infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-rays, and electron beams, preferably 250 nm or less, more preferably 220 nm or less, and particularly preferably far ultraviolet light having a wavelength of 1 to 200 nm, specifically KrF excimer laser (248 nm), ArF excimer laser (193 nm), _F2 excimer laser (157 nm), EUV (13.5 nm), X-rays, and electron beams.

After exposure, it is preferable to perform baking (heating) before development, which promotes the reaction of the exposed area and improves the sensitivity and pattern shape.
The heating temperature is preferably from 80 to 150°C, more preferably from 80 to 140°C, and even more preferably from 80 to 130°C.
The heating time is preferably from 10 to 1,000 seconds, more preferably from 10 to 180 seconds, and even more preferably from 30 to 120 seconds.
Heating can be carried out by a means provided in a normal exposure machine and/or developing machine, and may be carried out using a hot plate or the like.
This step is also called post-exposure bake.

(Step 3: Development Step)
Step 3 is a step of developing the exposed actinic ray- or radiation-sensitive film with a developer to form a pattern.
The developer may be an alkaline developer or a developer containing an organic solvent (hereinafter, also referred to as an organic developer).

Examples of the developing method include a method of immersing a substrate in a tank filled with a developing solution for a certain period of time (dip method), a method of piling up the developing solution on the substrate surface by surface tension and leaving it to stand for a certain period of time to develop (paddle method), a method of spraying the developing solution on the substrate surface (spray method), and a method of continuously discharging the developing solution while scanning a developing solution discharge nozzle at a constant speed onto a substrate rotating at a constant speed (dynamic dispense method).
After the development step, a step of stopping the development while replacing the solvent with another solvent may be carried out.
The development time is not particularly limited as long as the resin in the unexposed area is sufficiently dissolved, and is preferably from 10 to 300 seconds, more preferably from 20 to 120 seconds.
The temperature of the developer is preferably from 0 to 50°C, and more preferably from 15 to 35°C.

The alkaline developer is preferably an aqueous alkaline solution containing an alkali. There are no particular limitations on the type of the aqueous alkaline solution, but examples include an aqueous alkaline solution containing a quaternary ammonium salt such as tetramethylammonium hydroxide, an inorganic alkali, a primary amine, a secondary amine, a tertiary amine, an alcohol amine, or a cyclic amine. Of these, the alkaline developer is preferably an aqueous solution of a quaternary ammonium salt such as tetramethylammonium hydroxide (TMAH). Appropriate amounts of alcohols, surfactants, etc. may be added to the alkaline developer. The alkaline 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.

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.

The above-mentioned solvents may be mixed in combination, or may be mixed with a solvent other than the above or with water. The water content of the 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 free of water.
The content of the organic solvent in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, still more preferably 90% by mass or more and 100% by mass or less, and particularly preferably 95% by mass or more and 100% by mass or less, based on the total amount of the developer.

(Other processes)
The above pattern formation method preferably includes, after step 3, a step of cleaning with a rinsing liquid.

The rinse liquid used in the rinse step following the step of developing with an alkaline developer is, for example, pure water, to which an appropriate amount of a surfactant may be added.
A suitable amount of a surfactant may be added to the rinse solution.

The rinse liquid used in the rinse step following the development step using an organic developer is not particularly limited as long as it does not dissolve the pattern, and a solution containing a general organic solvent can be used. It is preferable to use a rinse liquid containing at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents.

The method of the rinsing step is not particularly limited, and examples thereof include a method of continuously discharging a rinsing liquid onto a substrate rotating at a constant speed (spin coating method), a method of immersing a substrate in a tank filled with the rinsing liquid for a certain period of time (dip method), and a method of spraying the rinsing liquid onto the substrate surface (spray method).
The pattern forming method may also include a heating step (Post Bake) after the rinsing step. This step removes the developer and rinsing solution remaining between the patterns and inside the pattern due to baking. This step also has the effect of annealing the resist pattern and improving the surface roughness of the pattern. The heating step after the rinsing step is usually performed at 40 to 250°C (preferably 90 to 200°C) for usually 10 seconds to 3 minutes (preferably 30 seconds to 120 seconds).

Furthermore, the formed pattern may be used as a mask to perform an etching process on the substrate. That is, the pattern formed in step 3 may be used as a mask to process the substrate (or the underlayer film and the substrate) to form a pattern on the substrate.
Although the method for processing the substrate (or the underlayer film and the substrate) is not particularly limited, a method is preferred in which the substrate (or the underlayer film and the substrate) is dry-etched using the pattern formed in step 3 as a mask to form a pattern on the substrate. The dry etching is preferably oxygen plasma etching.

The composition of the present invention and various materials used in the pattern formation method (e.g., solvent, developer, rinse, anti-reflective film forming composition, top coat forming composition, etc.) preferably do not contain impurities such as metals. The content of impurities contained in these materials is preferably 1 mass ppm (parts per million) or less, more preferably 10 mass ppb (parts per billion) or less, even more preferably 100 mass ppt (parts per trillion) or less, particularly preferably 10 mass ppt or less, and most preferably 1 mass ppt or less. There is no particular lower limit, and 0 mass ppt or more is preferable. Here, examples of metal impurities include Na, K, Ca, Fe, Cu, Mg, Al, Li, Cr, Ni, Sn, Ag, As, Au, Ba, Cd, Co, Pb, Ti, V, W, and Zn.

An example of a method for removing impurities such as metals from various materials is filtration using a filter. Details of filtration using a filter are described in paragraph [0321] of WO 2020/004306.

Methods for reducing metal and other impurities contained in various materials include, for example, selecting raw materials with low metal content as the raw materials that make up the various materials, filtering the raw materials that make up the various materials, and performing distillation under conditions that minimize contamination as much as possible, such as lining the inside of the equipment with Teflon (registered trademark).

In addition to filtration, impurities may be removed using an adsorbent, or a combination of filtration and an adsorbent may be used. As the adsorbent, known adsorbents can be used, for example, inorganic adsorbents such as silica gel and zeolite, and organic adsorbents such as activated carbon. In order to reduce impurities such as metals contained in the various materials described above, it is necessary to prevent the incorporation 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 contained in the cleaning solution used to clean the manufacturing equipment. The content of metal components contained 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, and 0 ppt by mass or more is preferable.

An organic processing liquid such as a rinse liquid may contain a conductive compound to prevent breakdown of chemical liquid piping and various parts (filters, O-rings, tubes, etc.) due to static charging and subsequent static discharge. The conductive compound is not particularly limited, but an example thereof is methanol. The amount added is not particularly limited, but from the viewpoint of maintaining favorable development characteristics or rinsing characteristics, it is preferably 10% by mass or less, and more preferably 5% by mass or less. There is no particular lower limit, and 0.01% by mass or more is preferable.
The chemical liquid piping may be made of, for example, stainless steel (SUS), or various piping coated with antistatic polyethylene, polypropylene, or fluororesin (polytetrafluoroethylene, perfluoroalkoxy resin, etc.). Similarly, the filter and O-ring may be made of antistatic polyethylene, polypropylene, or fluororesin (polytetrafluoroethylene, perfluoroalkoxy resin, etc.).

[Electronic device manufacturing method]
The present specification also relates to a method for manufacturing an electronic device, including the above-mentioned pattern formation method, and an electronic device manufactured by this manufacturing method.
Preferred embodiments of the electronic device of the present specification include those mounted in electric and electronic equipment (home appliances, OA (Office Automation), media-related equipment, optical equipment, communication equipment, and the like).

The present invention will be described in more detail below based on examples. The materials, amounts used, ratios, processing contents, and processing procedures shown in the following examples can be changed 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.

The various components used in the resist compositions of the examples and comparative examples are shown below.

<Resin (A)>
As the resin (A), A-1 to A-12 were used.
Resin (A) used was synthesized according to the synthesis method for resin A-1 (Synthesis Example 1) described below.
The structures of A-1 to A-12 are shown below. The content ratio of the following repeating units (content relative to the total repeating units in the resin) is a molar ratio.
The weight average molecular weight (Mw) and dispersity (Pd=Mw/Mn) of the resin were measured by GPC (carrier: tetrahydrofuran (THF)) (polystyrene equivalent amount). The repeating unit content was measured by ¹³ C-NMR (nuclear magnetic resonance).
A-1 to A-12 are acid-decomposable resins.

A synthesis example of Resin A-1 is shown below. Other resins (A) were synthesized in the same manner.
(Synthesis Example 1: Synthesis of Resin A-1)

Cyclohexanone (45.5 g) was heated to 85°C under a nitrogen stream. A mixed solution of AS-1 (13.6 g), 4-vinylstyrene (29.7 g), cyclohexanone (84.4 g), and 2,2'-azobisisobutyric acid dimethylate [V-601, Fujifilm Wako Pure Chemical Industries, Ltd.] (3.1 g) was added dropwise to this liquid while stirring over a period of 3 hours to obtain a reaction liquid. After the addition was completed, the reaction liquid was stirred at 85°C for an additional 3 hours. The resulting reaction liquid was allowed to cool, and then reprecipitated with 2300 g of ethyl acetate/heptane (mass ratio 1:9), filtered, and the resulting solid was vacuum dried to obtain Resin A-1 (35.1 g).

<Salt (B)>
As the salt (B), b-1 to b-10 were used.
The salt (B) used was synthesized according to the synthesis method of b-1 (Synthesis Example 2) or the synthesis method of b-2 (Synthesis Example 3) described below.
The structures of b-1 to b-10 are shown below.

The synthesis example of b-1 is shown below. b-3 to b-8 were also synthesized in the same way.

(Synthesis example 2: Synthesis of b-1)

Compound 1 (1.0 g) was dissolved in acetonitrile (6 ml) and cooled to 0° C. Compound 2 (1.1 g) dissolved in acetonitrile (5 ml) was added dropwise thereto, and after stirring for 10 minutes, the temperature was raised to room temperature (about 25° C.) while stirring. The reaction solution was then concentrated to obtain a crude product, to which cyclopentyl methyl ether (20 ml) was added and stirred, and the solid was filtered and dried to obtain compound 3 (1.1 g).
The obtained compound 3 was added to methylene chloride (10 ml), and then compound 4 (1.5 g) and water (10 ml) were added and the mixture was separated. Cyclopentyl methyl ether (20 ml) was added to the obtained organic phase, and the methylene chloride was removed by concentration. The crystals of (b-1) (2.1 g) formed in the solution were collected by filtration.

The synthesis example of b-2 is shown below. b-9 to b-10 were also synthesized in the same way.

(Synthesis example 3: Synthesis of b-2)

Compound 5 (1.0 g) was dissolved in methylene chloride (20 ml) and cooled to 0° C. Compound 6 (2.6 g) was added thereto, and after stirring for 10 minutes, the temperature was raised to room temperature and further stirred for 1 hour. The reaction solution obtained was then concentrated, and cyclopentyl methyl ether (20 ml) was added to the obtained crude product and stirred, and the solid was filtered and dried to obtain compound 7 (1.7 g).
The obtained compound 7 was added to methylene chloride (15 ml), and then compound 8 (1.5 g) and water (15 ml) were added and separated, and water (15 ml) was added again to the obtained organic phase and separated. Cyclopentyl methyl ether (20 ml) was added to the obtained organic phase, and the methylene chloride was removed by concentration, and the crystals (b-2) (1.9 g) generated in the solution were collected by filtration.

<Photoacid generator (C)>
The structure of the photoacid generator (C) used is shown below.

<Acid Diffusion Controller (D)>
The structure of the acid diffusion controller (D) used is shown below.

<Hydrophobic resin>
The structure of the hydrophobic resin used is shown below: The content ratio of the following repeating units (content relative to all repeating units in the resin) is a molar ratio.

<Surfactant>
The surfactants used are shown below.
W-1: Megafac F176 (manufactured by Dainippon Ink and Chemicals, Inc.; fluorine-based)
W-2: Megafac R08 (manufactured by Dainippon Ink and Chemicals, Inc.; fluorine and silicone type)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.; silicone-based) W-4: Troisol S-366 (manufactured by Trois Chemical Co., Ltd.)
W-5: KH-20 (manufactured by Asahi Glass Co., Ltd.)
W-6: PolyFox PF-6320 (manufactured by OMNOVA Solutions Inc.; fluorine-based)

<Solvent>
The solvents used are shown below.
SL-1: Propylene glycol monomethyl ether acetate (PGMEA)
SL-2: Propylene glycol monomethyl ether propionate SL-3: 2-heptanone SL-4: Ethyl lactate SL-5: Propylene glycol monomethyl ether (PGME)
SL-6: Cyclohexanone SL-7: γ-butyrolactone SL-8: Propylene carbonate

[Preparation of Coating Solution of Resist Composition and Coating]
The components shown in Table 1 below were dissolved in the solvents shown in Table 1 below to prepare solutions with a solids concentration of 2.7% by mass. This was then filtered through a polyethylene filter having a pore size of 0.02 μm to obtain resist compositions R-1 to R-15 and Rx-1.
These resist compositions were applied onto a 6-inch Si (silicon) wafer that had been previously treated with hexamethyldisilazane (HMDS) using a spin coater Mark 8 manufactured by Tokyo Electron, and dried on a hot plate at 130° C. for 300 seconds to obtain a resist film with a thickness of 100 nm.
Here, 1 inch is 0.0254 m.
It should be noted that the same results can be obtained even if the Si wafer is replaced with a chromium substrate.

[Pattern formation method (1): EB exposure, alkaline development (positive)]
The wafer coated with the resist film obtained above was subjected to pattern irradiation using an electron beam lithography device (Advantest Corporation; F7000S, acceleration voltage 50 KeV). At this time, lithography was performed so that a 1:1 line and space was formed. After electron beam lithography, the wafer was heated on a hot plate at 100° C. for 60 seconds, immersed in a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds, rinsed with water for 30 seconds, and dried. Thereafter, the wafer was rotated at a rotation speed of 4000 rpm for 30 seconds, baked at 95° C. for 60 seconds, and dried.

[evaluation]
The cross-sectional shape of the obtained pattern was observed using a scanning electron microscope (S-9380II manufactured by Hitachi, Ltd.) The exposure dose required to resolve a 1:1 line and space resist pattern with a line width of 50 nm was defined as sensitivity (Eop).

<Roughness performance (LWR)>
When a 50 nm (1:1) line and space pattern resolved at an exposure dose showing the above sensitivity (Eop) was observed from above using a critical dimension scanning electron microscope (SEM (Hitachi, Ltd. S-9380II)), the line width of the pattern was observed at 250 points and the standard deviation (σ) was calculated. The measurement variation in line width was evaluated at 3σ, and the value of 3σ was defined as LWR (nm). The smaller the LWR value, the better the LWR performance.

<Development Defects>
The 1:1 line and space pattern with a line width of 50 nm formed at the above sensitivity (Eop) was measured in random mode using a defect inspection device KLA2360 manufactured by KLA Tencor Corporation, with the pixel size of the defect inspection device set to 0.16 μm and the threshold value set to 20, and development defects extracted from the differences arising from pixel-by-pixel overlay with the comparison image were detected, and the number of development defects per unit area (1 ^cm2 ) was calculated.
A value of less than 0.5 was rated as A, a value of 0.5 or more but less than 0.7 was rated as B, and a value of 0.7 or more was rated as C. The smaller the value, the better the performance.

Table 2 below shows the resist compositions used in each example and comparative example, and the results of each example and comparative example.

[Pattern formation method (2): EUV exposure, alkaline development (positive)]
The wafer coated with the resist film obtained above was subjected to pattern exposure using an EUV exposure device (Micro Exposure Tool, NA (numerical aperture) 0.3, Quadrupole, outer sigma 0.68, inner sigma 0.36, manufactured by Exitech) and an exposure mask (line/space = 1/1). After exposure, the wafer was heated at 100 ° C. for 90 seconds on a hot plate, immersed in a 2.38 mass% aqueous tetramethylammonium hydroxide (TMAH) solution for 60 seconds, and then rinsed with water for 30 seconds. The wafer was then rotated at a rotation speed of 4000 rpm for 30 seconds, baked at 95 ° C. for 60 seconds, and dried.

[evaluation]
The resists thus obtained were evaluated in the same manner as described above, and the evaluation results are shown in Table 3.

[Pattern formation method (3): EUV exposure, organic solvent development (negative)]
[Extreme ultraviolet (EUV) exposure, organic solvent development (negative)]
The wafer coated with the resist film obtained above was subjected to pattern exposure using an EUV exposure device (Micro Exposure Tool manufactured by Exitech, NA (numerical aperture) 0.3, quadrupole, outer sigma 0.68, inner sigma 0.36) and an exposure mask (line/space = 1/1). After exposure, the wafer was heated on a hot plate at 100°C for 90 seconds, developed with n-butyl acetate for 30 seconds, and spin-dried to obtain a negative pattern.

[evaluation]
The resists thus obtained were evaluated in the same manner as described above, and the evaluation results are shown in Table 4.

The results in Tables 2 to 4 show that the resist compositions used in the examples have excellent LWR performance and development defect suppression performance when forming ultrafine patterns.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application (Patent Application No. 2022-181320) filed on November 11, 2022, the contents of which are incorporated herein by reference.

Claims

An actinic ray- or radiation-sensitive resin composition containing a resin (A) and a salt (B) having a cation radical structure.
The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, wherein the salt (B) is a compound represented by the following general formula (B-1) or (B-2):

In general formula (B-1), Rb 1 to Rb 4 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a thiol group, an alkylthio group, an arylthio group, an amino group, a heteroaryl group, a carbonyl group, a cyano group, or a group consisting of a combination thereof, and may be bonded to each other to form a ring. A 1 - represents a counter anion.
In the general formula (B-2), Rb 5 to Rb 12 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a thiol group, an alkylthio group, an arylthio group, an amino group, a carbonyl group, a hydroxyl group, a cyano group, or a group consisting of a combination thereof. Rb 13 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group. X represents -S-, -O-, or -NRb 14 -. Rb 14 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group. Rb 5 to Rb 14 may be bonded to each other to form a ring. A 2 - represents a counter anion.
The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the salt (B) has a carboxylate anion or a sulfonate anion as a counter anion.
The actinic ray-sensitive or radiation-sensitive resin composition according to claim 2, wherein A 1 - in the general formula (B-1) or A 2 - in the general formula (B-2) is represented by any one of the following general formulae (AN1) to (AN3):

In formula (AN1), A Q1 - represents a carboxylate anion or a sulfonate anion. R 1 and R 2 each independently represent a hydrogen atom or a substituent. L Q1 represents a divalent linking group. R 3 represents an organic group.

In the general formula (AN2), A Q2 - represents a carboxylate anion or a sulfonate anion. Xf represents a hydrogen atom, a fluorine atom, an alkyl group substituted with at least one fluorine atom, or an organic group having no fluorine atom. R 4 and R 5 each independently represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom. L Q2 represents a divalent linking group. W represents an organic group. o represents an integer of 1 to 3. p represents an integer of 0 to 10. q represents an integer of 0 to 10. A plurality of Xf may be the same as or different from each other. When p represents an integer of 2 or more, a plurality of R 4 and R 5 may be the same as or different from each other. When q represents an integer of 2 or more, a plurality of L Q2 may be the same as or different from each other.

In general formula (AN3), A Q3 - represents a carboxylate anion or a sulfonate anion. Ar represents an aromatic group. n and m represent integers of 0 or more. D represents a single bond or a divalent linking group. B represents a hydrocarbon group. E represents a substituent other than a carboxylate anion, a sulfonate anion, and a -(D-B) group. When n represents an integer of 2 or more, a plurality of Ds and Bs may be the same as or different from each other. When m represents an integer of 2 or more, a plurality of Es may be the same as or different from each other.
The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the resin (A) is a resin having a group that decomposes under the action of an acid and increases its polarity.
The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the resin (A) has at least one repeating unit selected from the group consisting of a repeating unit represented by the following general formula (A-1) and a repeating unit represented by the following general formula (A-2):

In formula (A-1), Ra 1 to Ra 3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
La1 represents a single bond or a divalent linking group.
Ra 4 to Ra 6 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, or an alkenyl group. Two of Ra 4 to Ra 6 may be bonded to each other to form a ring.
Ra 0 represents an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, a hydroxyl group, an alkoxy group, an acyloxy group, an alkoxycarbonyl group, a halogen atom, or a cyano group. When a plurality of Ra 0 are present, the plurality of Ra 0 may be the same or different.
Two of Ra 1 to Ra 3 , La 1 and Ra 0 may be bonded to each other to form a ring.
na represents an integer of 0 to 4. ma represents an integer of 0 to 2.
In formula (A-2), Ra 7 to Ra 9 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.
La2 represents a single bond or a divalent linking group.
Ara represents an aromatic ring group.
Ra 10 to Ra 12 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aromatic heterocyclic group, an aralkyl group, an alkoxy group, a cycloalkyloxy group, or an alkenyl group.
At least two of Ra 10 to Ra 12 may be bonded to each other to form a ring.
At least one of Ra 9 to Ra 12 may be bound to Ara.
The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2, further comprising a compound that generates an acid upon exposure to actinic rays or radiation.
An actinic ray-sensitive or radiation-sensitive film formed from the actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2.
A pattern forming method comprising the steps of forming an actinic ray-sensitive or radiation-sensitive film on a substrate using the actinic ray-sensitive or radiation-sensitive resin composition according to claim 1 or 2, exposing the actinic ray-sensitive or radiation-sensitive film, and developing the exposed actinic ray-sensitive or radiation-sensitive film using a developer.
A method for manufacturing an electronic device comprising the pattern formation method according to claim 9.