Sulfonium salt, chemically amplified resist composition, and pattern forming method

Abstract

In photolithography using high energy rays, an onium salt used in a chemical amplification resist composition having excellent solvent solubility, high sensitivity, high contrast, and excellent lithography performance such as LWR, CDU, MEF, EL, and DOF is provided, a chemical amplification resist composition comprising said onium salt as a photogenerative agent, and a pattern forming method using said chemical amplification resist composition are provided. Sulfonium salt represented by the following formula (1). (In the formula, Z- is a fluoroalkanesulfonate anion that does not possess a polymerizable group.)

Description

Technology Field

[0001] The present invention relates to a sulfonium salt, a chemical amplification resist composition, and a pattern forming method. Background Technology

[0002] In recent years, as the miniaturization of pattern rules is required alongside the high integration and high speed of LSIs, far ultraviolet lithography and extreme ultraviolet (EUV) lithography are considered promising as next-generation microfabrication technologies.

[0003] Photolithography using ArF excimer laser light (ArF lithography) began to be partially used in the fabrication of 130 nm node devices and became the main lithography technology from 90 nm node devices. As the next lithography technology for the 45 nm node, lithography using an F2 laser with a wavelength of 157 nm was initially considered promising, but development delays due to various problems were pointed out. Consequently, ArF immersion lithography, which enables high resolution by inserting a liquid with a high refractive index from air—such as water, ethylene glycol, or glycerin—between the projection lens and the wafer, thereby allowing the projection lens's numerical aperture (NA) to be designed to be 1.0 or higher, has been commercialized. This immersion lithography requires a resist composition that is difficult to dissolve in water.

[0004] In ArF lithography, a highly sensitive resist composition capable of achieving sufficient resolution with a small amount of exposure is required to prevent degradation of the precise and expensive optical materials. As a method to achieve this, it is most common to select a component that is highly transparent at a wavelength of 193 nm. For example, regarding the base polymer, polyacrylic acid and its derivatives, norbornene-maleic anhydride alternating polymers, polynorbornene, ring-opening metathesis polymers, and ring-opening metathesis polymer hydrogenated derivatives have been proposed, and some results have been achieved in terms of increasing the transparency of the resin itself.

[0005] In recent years, along with positive tone resists developed by alkaline aqueous solutions, negative tone resists developed by organic solvents have also been gaining attention. Since very fine hole patterns that cannot be achieved with positive tones are resolved by negative tone exposure, a negative pattern is formed by developing with an organic solvent using a positive-type resist composition with high resolution. In addition, research is being conducted to obtain double the resolution by combining two development steps of alkaline aqueous solution development and organic solvent development. As an ArF resist composition for negative tone development by organic solvents, a conventional positive-type ArF resist composition can be used, and a method for forming a pattern using this is described in Patent Documents 1 to 3.

[0006] To adapt to the rapid miniaturization of recent years, the development of resist compositions is progressing daily alongside process technologies. Various photogenerators are being considered, and sulfonium salts containing triphenylsulfonium cations and perfluoroalkanesulfonic acid anions are commonly used. However, the generated acids, perfluoroalkanesulfonic acids, particularly perfluorooctanesulfonic acid (PFOS), raise concerns regarding their recalcitrant nature, bioaccumulation, and toxicity. Consequently, their application in resist compositions is strict, and currently, photogenerators generating perfluorobutanesulfonic acid are being used. However, using this in resist compositions results in significant diffusion of the generated acid, making it difficult to achieve high resolution. Regarding this issue, various partially fluorinated alkanesulonic acids and their salts have been developed. For example, Patent Document 1 describes, as prior art, a photogenerator that generates α,α-difluoroalkanesulonic acid by exposure to light, specifically, a photogenerator that generates di(4-tert-butylphenyl)iodonium 1,1-difluoro-2-(1-naphthyl)ethanesulfonate or α,α,β,β-tetrafluoroalkanesulonic acid. However, although the fluorine substitution rate is lowered, these do not have degradable substituents such as ester structures, so they are insufficient from the perspective of environmental safety due to degradability. Additionally, there are limitations in molecular design for changing the size of alkanesulonic acid, and starting materials containing fluorine atoms are expensive.

[0007] Furthermore, with the reduction in circuit linewidth, the impact of contrast degradation caused by acid diffusion on resist compositions has become increasingly severe. This is because the pattern dimensions approach the length of the acid diffusion, leading to a decrease in mask fidelity and a deterioration in pattern rectangularity as the ratio of the dimensional deviation on the wafer (Mask Error Factor (MEF)) to the dimensional deviation of the mask increases. Therefore, to fully obtain the benefits of shorter wavelengths and higher NAs of the light source, it is necessary to increase dissolution contrast or suppress acid diffusion beyond that of conventional materials. As one solution, lowering the bake temperature reduces acid diffusion and consequently improves the MEF, but this inevitably results in reduced sensitivity.

[0008] Introducing bulky substituents or polar groups into photogenerators is effective in suppressing acid diffusion. Patent Document 4 describes a photogenerator having 2-acyloxy-1,1,3,3,3-pentafluoropropane-1-sulfonic acid, which has excellent solubility and stability in solvents and allows for a wide range of molecular designs. In particular, a photogenerator having 2-(1-adamanthyloxy)-1,1,3,3,3-pentafluoropropane-1-sulfonic acid with bulky substituents introduced exhibits low acid diffusion. Additionally, Patent Documents 5 to 7 describe photogenerators having condensed ring lactones, sulfones, or thiolactones introduced as polar groups. Although some performance improvement has been confirmed due to the acid diffusion suppression effect caused by the introduction of polar groups, it is still insufficient for high-level control of acid diffusion, and considering MEF, pattern shape, sensitivity, etc., the lithography performance is not satisfactory.

[0009] Introducing polar groups to the anions of photogenerators is effective in suppressing acid diffusion, but it is disadvantageous in terms of solvent solubility. In Patent Documents 8 and 9, attempts are made to secure solvent solubility by introducing alicyclic groups into the cations of photogenerators to improve solvent solubility, specifically introducing cyclohexane rings or adamantan rings. Although solubility is improved by introducing such alicyclic groups, a certain number of carbon atoms is required to secure solubility, and consequently, the molecular structure of the photogenerator becomes bulky, which degrades lithography performance such as line withstand roughness (LWR) and dimensional uniformity (CDU) during the formation of fine patterns.

[0010] Patent document 10 describes a photogenerator that generates a fluoroalkanesulfonic acid having an aromatic condensed ring derived from anthracene in the anion.

[0011] Since iodine atoms have a very high absorption rate of EUV with a wavelength of 13.5 nm, the effect of secondary electron generation from iodine atoms during exposure has been confirmed and is receiving attention in EUV lithography. Patent Document 11 describes a photogenerator in which iodine atoms are introduced into an anion, and Patent Document 12 describes a photogenerator containing a polymerizable group in which iodine atoms are introduced into an anion. Patent Document 13 describes a photogenerator in which iodine atoms are introduced into both a cation and an anion. Although some improvement in lithography performance has been confirmed by this, iodine atoms do not have high solubility in organic solvents, so there is concern about precipitation in the solvent.

[0012] Patent Document 14 describes a photogenerator in which multiple fluorine atoms are introduced into a cation. Although the introduction of multiple fluorine atoms improves the solvent solubility of the photogenerator, it is not sufficient from the perspective of EUV absorption, leaving room for improvement.

[0013] Patent documents 15 to 19 describe photocatalytic agents or quenchers (acid diffusion control agents) containing iodine and fluorine atoms in the cation. While these developments have confirmed improvements in performance as resist materials, they are not yet satisfactory in terms of acid diffusion control, and further development of resist materials useful for forming fine patterns is required. Prior art literature

[0014] Japanese Patent Publication No. 2008-281974 Japanese Patent Publication No. 2008-281975 Japanese Patent No. 4554665 Japanese Patent Publication No. 2007-145797 Japanese Patent No. 5061484 Japanese Patent Publication No. 2016-147879 Japanese Patent Publication No. 2015-63472 Japanese Patent No. 5573098 Japanese Patent No. 6461919 Japanese Patent No. 7109178 Japanese Patent No. 6720926 Japanese Patent No. 6973274 Japanese Patent No. 7041204 Japanese Patent No. 7389562 Japanese Patent Publication No. 2021-123579 Japanese Patent Publication No. 2021-123580, Japanese Patent Publication No. 2022-123839, Japanese Patent Publication No. 2023-88869, Japanese Patent Publication No. 2023-88870

[0015] Journal of Photopolymer Science and Technology, Vol.17, No.4, p.587-601 (2004) The problem to be solved

[0016] In response to the recent demand for high resolution in resist patterns, conventional resist compositions using onium salt-type photocatalysts cannot sufficiently suppress acid diffusion, and as a result, lithography performance such as contrast, LWR, CDU, MEF, exposure margin (EL), and depth of focus (DOF) may deteriorate.

[0017] The present invention has been made in consideration of the above circumstances, and aims to provide an onium salt used in a chemical amplification resist composition that has excellent solvent solubility, high sensitivity, high contrast, and excellent lithography performance such as LWR, CDU, MEF, EL, and DOF, particularly in photolithography using high-energy rays such as KrF excimer laser light, ArF excimer laser light, electron beam (EB), and EUV, a chemical amplification resist composition comprising said onium salt as a photocatalytic agent, and a pattern forming method using said chemical amplification resist composition. means of solving the problem

[0018] The inventors, having repeatedly examined the above objective, discovered that a sulfonium salt comprising a fluoroalkanesulfonic acid anion not having a polymerizable group and a sulfonium cation having a pentafluorosulfanyl group and a hydrocarbyloxycarbonyl group has excellent solvent solubility, and that a chemical amplification resist composition using this as a photogenerator has high sensitivity and high contrast, is very effective in inhibiting acid diffusion, has excellent lithography performance such as LWR, CDU, MEF, EL, and DOF, and is very effective in forming fine patterns, thereby leading to the present invention.

[0019] That is, the present invention provides the following sulfonium salt, chemical amplification resist composition, and pattern forming method.

[0020] 1. A sulfonium salt represented by the following formula (1).

[0021]

[0022] (In the equation, n1 is 0 or 1. n2 is 0, 1 or 2. n3 is 0, 1 or 2. n4 is 0, 1 or 2. Provided that when n1 is 0, 0 ≤ n2 + n3 + n4 ≤ 5, and when n1 is 1, 0 ≤ n2 + n3 + n4 ≤ 7. n5 is 0 or 1. n6 is 0, 1 or 2. n7 is 0, 1 or 2. n8 is 0, 1 or 2. Provided that when n5 is 0, 0 ≤ n6 + n7 + n8 ≤ 5, and when n5 is 1, 0 ≤ n6 + n7 + n8 ≤ 7. n9 is 0 or 1. n10 is 0, 1 or 2. n11 is 0, 1 or 2. n12 is 0, 1 or 2. However, when n9 is 0, 0 ≤ n10 + n11 + n12 ≤ 5, and when n9 is 1, 0 ≤ n10 + n11 + n12 ≤ 7. Also, 1 ≤ n2 + n6 + n10 ≤ 6, and 1 ≤ n3 + n7 + n11 ≤ 6.

[0023] R 1 , R 2 and R 3 It is a hydrocarbyl group having 1 to 20 carbon atoms, each of which may independently contain a heteroatom. When n3 is 2, each R 1 They may be identical or different. When n7 is 2, each R 2 They may be identical or different. When n11 is 2, each R 3 They may be identical or different.

[0024] R 4 , R 5 and R 6 Each is independently a halogen atom, a nitro group, a hydroxyl group, a carboxyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom. When n4 is 2, each R 4 They may be identical or different from each other, and 2 R 4They may bond with each other to form a ring together with the carbon atom they bond to. When n8 is 2, each R 5 They may be identical or different from each other, and 2 R 5 They may bond with each other to form a ring together with the carbon atom they bond to. When n12 is 2, each R 6 They may be identical or different from each other, and 2 Rs 6 They may combine with each other to form a ring together with the carbon atoms they bond to.

[0025] Also, S + Two of the three aromatic rings bonded to it may bond with each other to form a ring together with the sulfur atom they bond to.

[0026] Z - is a fluoroalkanesulfonate anion that does not possess a polymerizable group.

[0027] 2. A sulfonium salt of 1 represented by the following formula (1A).

[0028]

[0029] (among the food, n2 to n4, n6 to n8, n10 to n12, R 1 to R 6 and Z - is the same as above.)

[0030] 3. Z - a. A sulfonium salt of 1 or 2 which is an anion represented by any one of the following formulas (Z-1) to (Z-3).

[0031]

[0032] (during food, R 11 It is a hydrocarbyl group having 1 to 60 carbon atoms that may contain a fluorine atom or a heteroatom.

[0033] R 12 It is a hydrocarbyl group having 1 to 40 carbon atoms that may contain heteroatoms.

[0034] x is 1, 2, or 3. y is 1, 2, 3, 4, or 5. z is 0, 1, 2, or 3, provided that 1 ≤ y + z ≤ 5.

[0035] X BI is an iodine atom or a bromine atom.

[0036] L 1 The group is a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a carbamate bond, or a saturated hydrocarbylene group having 1 to 6 carbon atoms, and a portion of the -CH2- of the hydrocarbylene group may be substituted with an ether bond or an ester bond.

[0037] L 2 When x is 1, it is a hydrocarbylene group having 1 to 20 carbon atoms that may contain single bonds or heteroatoms, and when x is 2 or 3, it is a hydrocarbon group having 1 to 20 carbon atoms that may contain heteroatoms.

[0038] L 3 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, carbonate bond, or carbamate bond.

[0039] R 13 hydroxyl group, carboxyl group, fluorine atom, chlorine atom, bromine atom, pentafluorosulfanyl group, amino group, hydrocarbyl group having 1 to 20 carbon atoms, hydrocarbyloxy group having 1 to 20 carbon atoms, hydrocarbylthio group having 1 to 20 carbon atoms, hydrocarbylcarbonyl group having 2 to 20 carbon atoms, hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms, hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms, hydrocarbylsulfonyloxy group having 1 to 20 carbon atoms, -N(R 13A )(R 13B ), -N(R 13C )-C(=O)-R 13D or -N(R 13C )-C(=O)-OR 13DAnd, the corresponding hydrocarbyl group, hydrocarbyloxy group, hydrocarbylthio group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may include at least one selected from a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a hydroxyl group, an amino group, an ester bond, and an ether bond. R 13A and R 13B is, each independently, a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. R 13C is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may include a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. 13D The group is an aliphatic hydrocarbyl group having 1 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may include a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms.

[0040] Rf 1 to Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They may combine to form a carbonyl group.)

[0041] 4. A photocatalytic agent comprising a sulfonium salt of any one of 1 to 3.

[0042] 5. A chemical amplification resist composition comprising a photogenerative agent of 4.

[0043] 6. Additionally, a chemical amplification resist composition of 5 comprising a base polymer comprising at least one selected from a repeating unit represented by the following formula (a1), a repeating unit represented by the following formula (a2), and a repeating unit represented by the following formula (a3).

[0044]

[0045] (during food, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0046] X 1 It consists of single bonds, phenylene groups, naphthylene groups, or *-C(=O)-OX 11 - and, the phenylene group or naphthylene group may be substituted with a hydroxyl group, a nitro group, a cyano group, a saturated hydrocarbyl group having 1 to 10 carbon atoms that may include a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms that may include a fluorine atom, or a halogen atom. X 11 The group is a saturated hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may include a hydroxyl group, an ether bond, an ester bond, or a lactone ring.

[0047] X 2 is a single bond or *-C(=O)-O-.

[0048] * indicates the bond loss with carbon atoms in the main chain.

[0049] R 21It is a halogen atom, a cyano group, a hydroxyl group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom. When a1 is 2, 3, or 4, each R 21 They may be identical or different.

[0050] AL 1 and AL 2 Each is an independent mountain instability phase.

[0051] a1 is 0, 1, 2, 3, or 4.)

[0052]

[0053] (In the equation, b1 is 0 or 1. b2 is 0, 1, 2 or 3 when b1 is 0, and 0, 1, 2, 3, 4 or 5 when b1 is 1.

[0054] R A is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0055] X 3 is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-. * indicates a bond loss with a carbon atom in the main chain.

[0056] X 4 It is a single bond, an aliphatic hydrocarbylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a combination thereof.

[0057] X 5 and X 6 Each is independently an oxygen atom or a sulfur atom. However, X 4 and X6 The aromatic ring is bonded to an adjacent carbon atom.

[0058] R 22 and R 23 It is a hydrocarbyl group having 1 to 20 carbon atoms, which may each independently contain a hydrogen atom or a heteroatom. Also, R 22 and R 23 These may combine with each other to form a ring together with the carbon atoms they bond to.

[0059] R 24 is a halogen atom, a hydroxyl group, a cyano group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom, or -N(R 24A )(R 24B ) is. R 24A and R 24B Each is independently a hydrogen atom or a hydrocarbyl group having 1 to 6 carbon atoms. When b2 is 2 or more, each R 24 may be identical or different from each other, and multiple R 24 They may bond with each other to form a ring together with the carbon atoms of the aromatic ring to which they bond.

[0060] 7. A chemical amplification resist composition of 6 in which the polymer comprises repeating units represented by the following formula (b1) or (b2).

[0061]

[0062] (during food, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0063] Y 1It is a single bond or *-C(=O)-O-. * indicates a bond loss with a carbon atom in the main chain.

[0064] R 31 It is a group having 1 to 20 carbon atoms comprising at least one structure selected from hydrogen atoms, or hydroxyl groups other than phenolic hydroxyl groups, cyano groups, carbonyl groups, carboxyl groups, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, lactone rings, sulfone rings, and carboxylic acid anhydrides (-C(=O)-OC(=O)-).

[0065] R 32 is a halogen atom, a carboxyl group, a nitro group, a cyano group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom. When c2 is 2, 3, or 4, each R 32 They may be identical or different.

[0066] c1 is 1, 2, 3, or 4. c2 is 0, 1, 2, 3, or 4. Provided that 1 ≤ c1 + c2 ≤ 5.

[0067] 8. A chemical amplification resist composition of 6 or 7 comprising at least one selected from the repeating unit represented by the following formula (c1), the repeating unit represented by the following formula (c2), the repeating unit represented by the following formula (c3), the repeating unit represented by the following formula (c4), and the repeating unit represented by the following formula (c5).

[0068]

[0069] (In the equation, d1 and d2 are each independently 0, 1, 2 or 3.

[0070] e1 is 0 or 1. e2 is 0, 1, 2, 3, or 4. e3 is 0, 1, 2, 3, or 4. Provided that when e1 is 0, 0 ≤ e2 + e3 ≤ 4, and when e1 is 1, 0 ≤ e2 + e3 ≤ 6.

[0071] R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0072] Z 1 It is a phenylene group that may have a single bond or a substituent.

[0073] Z 2 is a single bond, **-C(=O)-OZ 21 -, **-C(=O)-N(H)-Z 21 - or **-OZ 21 -is. Z 21 It is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by combining these, and may include a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0074] Z 3 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0075] Z 4 It is a single bond, or an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by combining these, and may include a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0076] Z 5 are, respectively, a single bond, a phenylene group that may have a substituent, a naphthylene group that may have a substituent, and *-C(=O)-OZ 51- or *-C(=O)-N(R)-Z 51 -is. Z 51 is an aliphatic hydrocarbylene group having 1 to 10 carbon atoms, a phenylene group, or a naphthylene group, and the aliphatic hydrocarbylene group may include a halogen atom, a hydroxyl group, an ether bond, an ester bond, or a lactone ring. R is a hydrocarbylene group having 1 to 10 carbon atoms that may include a hydrogen atom or a heteroatom.

[0077] Z 6 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0078] Z 7 Silver, each independently single bond, ***-Z 71 -C(=O)-O-, ***-C(=O)-N(R)-Z 71 - or ***-OZ 71 -is. Z 71 It is a hydrocarbylene group having 1 to 20 carbon atoms that may contain heteroatoms. R is the same as above.

[0079] Z 8 Silver, each independently single bond, ****-Z 81 -C(=O)-O-, ****-C(=O)-N(R)-Z 81 - or ****-OZ 81 -is. Z 81 It is a hydrocarbylene group having 1 to 20 carbon atoms that may contain heteroatoms. R is the same as above.

[0080] Z 9 is a single bond, methylene group, ethylene group, phenylene group, fluorinated phenylene group, phenylene group substituted with a trifluoromethyl group, *-C(=O)-OZ 91 -, *-C(=O)-N(R)-Z 91 - or *-OZ 91 -is. Z 91is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a phenylene group substituted with a trifluoromethyl group, and may include a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. R is the same as above.

[0081] * indicates bond loss with carbon atoms in the main chain. ** is Z 1 Indicates the bonding loss with. *** is Z 6 Indicates the bond with. **** is Z 7 It represents the bonding hand with.

[0082] L 11 It is a single bond, ether bond, ester bond, carbonyl group, sulfonic acid ester bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0083] Rf 11 and Rf 12 Each is independently a fluorine atom or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms.

[0084] Rf 13 and Rf 14 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms.

[0085] Rf 15 and Rf 16 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. provided that all Rf 15 and Rf 16 There is no simultaneous occurrence of becoming a hydrogen atom.

[0086] Rf 17 It is a fluorine atom, a C1 to C6 fluorinated alkyl group, a C1 to C6 fluorinated alkoxy group, a C1 to C6 fluorinated alkylthio group, or a pentafluorosulfanyl group. When e2 is 2, 3, or 4, each Rf 17 They may be identical or different.

[0087] R 41 and R 42 is a hydrocarbyl group having 1 to 20 carbon atoms, which may each independently contain a heteroatom. Also, R 41 and R 42 They may combine with each other to form a ring together with the sulfur atom they combine with.

[0088] R 43 It is a hydrocarbyl group having 1 to 20 carbon atoms that may contain halogen atoms other than fluorine atoms or heteroatoms. When e3 is 2, 3, or 4, each R 43 They may be identical or different from each other, and multiple R 43 They may combine with each other to form a ring together with the carbon atoms they bond to.

[0089] M - is a non-nucleophilic counterion.

[0090] A + is an onium cation.)

[0091] 9. Additionally, a chemical amplification resist composition of any one of 5 to 8 comprising an organic solvent.

[0092] 10. Additionally, a chemical amplification resist composition of any one of 5 to 9 comprising a quencher.

[0093] 11. Additionally, a chemical amplification resist composition of any one of 5 to 10 comprising a photogenerative agent other than the photogenerative agent of 4.

[0094] 12. Additionally, a chemical amplification resist composition of any one of 5 to 11 comprising a surfactant.

[0095] 13. A pattern forming method comprising: a process of forming a resist film on a substrate using a chemical amplification resist composition of any one of 5 to 12; a process of exposing the resist film to high-energy rays; and a process of developing the exposed resist film using a developer.

[0096] 14. A method for forming a pattern of 13 in which the high-energy line is KrF excimer laser light, ArF excimer laser light, EB, or EUV with a wavelength of 3 to 15 nm. Effects of the invention

[0097] When pattern formation is performed using a chemically amplified resist composition containing the sulfonium salt of the present invention as a photocatalytic agent, high sensitivity and excellent acid diffusion inhibition ability are achieved, and lithography performance such as LWR, CDU, MEF, EL, and DOF is improved, thereby suppressing the breakdown of the resist pattern during fine pattern formation. Specific details for implementing the invention

[0098] The present invention will be described in detail below. In addition, in the following description, depending on the structure represented by the chemical formula, an asymmetric carbon may be present, and enantiomers or diastereomers may be present, but in such cases, the isomers are represented by a single formula. The isomers may be used as a single type or as a mixture of two or more types.

[0099] [Sulfonium salts]

[0100] The sulfonium salt of the present invention is represented by the following formula (1).

[0101]

[0102] In Equation (1), n1 is 0 or 1. When n1 is 0, it is a benzene ring, and when n1 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable for n1 to be a benzene ring of 0. n2 is 0, 1, or 2. n3 is 0, 1, or 2. n4 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable for n4 to be 0 or 1. However, when n1 is 0, 0 ≤ n2 + n3 + n4 ≤ 5, and when n1 is 1, 0 ≤ n2 + n3 + n4 ≤ 7.

[0103] In Equation (1), n5 is 0 or 1. When n5 is 0, it is a benzene ring, and when n5 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable for n5 to be a benzene ring of 0. n6 is 0, 1, or 2. n7 is 0, 1, or 2. n8 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable for n8 to be 0 or 1. However, when n5 is 0, 0 ≤ n6 + n7 + n8 ≤ 5, and when n5 is 1, 0 ≤ n6 + n7 + n8 ≤ 7.

[0104] In Equation (1), n9 is 0 or 1. When n9 is 0, it is a benzene ring, and when n9 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable for n9 to be a benzene ring of 0. n10 is 0, 1, or 2. n11 is 0, 1, or 2. n12 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable for n12 to be 0 or 1. However, when n9 is 0, 0 ≤ n10 + n11 + n12 ≤ 5, and when n9 is 1, 0 ≤ n10 + n11 + n12 ≤ 7.

[0105] In formula (1), the number of pentafluorosulfanyl groups is 1 ≤ n3 + n7 + n11 ≤ 6, but preferably 1 ≤ n3 + n7 + n11 ≤ 3, and more preferably 1 ≤ n3 + n7 + n11 ≤ 2. When the number of pentafluorosulfanyl groups is 2 or more, each pentafluorosulfanyl group may be attached to the same aromatic ring or to a different aromatic ring.

[0106] In formula (1), the number of hydrocarbyloxycarbonyl groups is 1 ≤ n2 + n6 + n10 ≤ 6, but preferably 1 ≤ n2 + n6 + n10 ≤ 3, and more preferably 1 ≤ n2 + n6 + n10 ≤ 2. When the number of hydrocarbyloxycarbonyl groups is 2 or more, each hydrocarbyloxycarbonyl group may be bonded to the same aromatic ring or to different aromatic rings.

[0107] In Equation (1), R 1 , R 2 and R 3The hydrocarbyl group having 1 to 20 carbon atoms may each independently contain a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples include alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecyl, octadecyl, nonadecyl, and icosyl. Examples include cyclic saturated hydrocarbyl groups having 3 to 20 carbon atoms, such as cyclopropyl groups, cyclopentyl groups, cyclohexyl groups, cyclopropylmethyl groups, 4-methylcyclohexyl groups, cyclohexylmethyl groups, norbornyl groups, adamantyl groups; aryl groups having 6 to 30 carbon atoms, such as phenyl groups, naphthyl groups, and benzyl groups; aralkyl groups having 7 to 30 carbon atoms, such as benzyl groups, 1-phenylethyl groups, and 2-phenylethyl groups; and groups obtained by combining these, but are not limited thereto.

[0108] In addition, some or all of the hydrogen atoms of the above hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- of the above hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. Specific examples of a hydrocarbyl group containing heteroatoms include fluorine alkyl groups such as a trifluoromethyl group, a 1,1,1-trifluoroethyl group, a 1,1,1,3,3,3-hexafluoroisopropyl group, a nonafluorobutyl group, or an octafluoropentyl group; Examples include oxanorbornyl groups, but are not limited to these. The above fluorine alkyl group preferably has 1 to 6 carbon atoms.

[0109] When n3 is 2, each R 1 They may be identical or different. When n7 is 2, each R 2 They may be identical or different. When n11 is 2, each R 3 They may be identical or different.

[0110] In Equation (1), R 4 , R 5 and R 6Each is a hydrocarbyl group having 1 to 20 carbon atoms that may independently contain a halogen atom, a nitro group, a hydroxyl group, a carboxyl group, or a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom. Examples of the halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. The hydrocarbyl portion of the hydrocarbyl group, hydrocarbyloxy group, and hydrocarbylthio group may be saturated or unsaturated, and may be straight, branched, or cyclic. Specific examples thereof include: an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an icosyl group, etc.; a cyclic saturated hydrocarbyl group having 3 to 20 carbon atoms, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclopropylmethyl group, a 4-methylcyclohexyl group, a cyclohexylmethyl group, a norbornyl group, an adamantyl group, etc. Examples include alkenyl groups having 2 to 20 carbon atoms, such as vinyl groups, 1-propenyl groups, 2-propenyl groups, butenyl groups, and hexenyl groups; cyclic unsaturated hydrocarbyl groups having 3 to 20 carbon atoms, such as cyclohexenyl groups; aryl groups having 6 to 20 carbon atoms, such as phenyl groups and naphthyl groups; aralkyl groups having 7 to 20 carbon atoms, such as benzyl groups, 1-phenylethyl groups, and 2-phenylethyl groups; and groups obtained by combining these. Among these, preferably, it is an aryl group.In addition, some or all of the hydrogen atoms of the above hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- of the above hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. When n4 is 2, each R. 4 They may be identical or different. Also, when n4 is 2, the 2 R 4 a, they may bond with each other to form a ring together with the carbon atom to which they bond. As the ring, a 5 to 8-membered ring is preferred. When n8 is 2, each R 5 They may be identical or different. Also, when n8 is 2, the 2 R 5 These may bond with each other to form a ring together with the carbon atom to which they bond. As for the ring, a 5 to 8-membered ring is preferred. When n12 is 2, each R 6 They may be identical or different. Also, when n12 is 2, 2 R 6 These may combine with each other to form a ring together with the carbon atom to which they are bonded. As for the ring, a 5 to 8-membered ring is preferred.

[0111] Also, S + Two of the three aromatic rings bonded to may bond with each other to form a ring together with the sulfur atom to which they bond. In this case, specific examples of the structure of the ring may include those represented by the following formula.

[0112]

[0113] (In the formula, the dashed line is a connecting hand.)

[0114] As for the sulfonium salt represented by formula (1), it is preferable to represent it by the following formula (1A).

[0115]

[0116] (among the food, n2 to n4, n6 to n8, n10 to n12 and R 1 to R 6 is the same as above. Z - (This will be discussed later.)

[0117] Specific examples of the cation of the sulfonium salt represented by formula (1) are shown below, but are not limited thereto. In addition, in the following formula, Me is a methyl group.

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153]

[0154]

[0155]

[0156]

[0157]

[0158]

[0159]

[0160]

[0161]

[0162]

[0163]

[0164]

[0165] Among equations (1) and (1A), Z - is a fluoroalkanesulfonic acid anion that does not have a polymerizable group. As for the fluoroalkanesulfonic acid anion, it is preferable to represent it with any of the following formulas (Z-1) to (Z-3).

[0166]

[0167] In equation (Z-1), R 11 It is a hydrocarbyl group having 1 to 60 carbon atoms that may contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, R in formula (Z-1-1) described below. 11a Examples of hydrocarbyl groups represented by [ ] can be given as examples. In addition, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, or nitrogen atoms, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0168] As for the anion represented by formula (Z-1), it is preferable to represent it by the following formula (Z-1-1).

[0169]

[0170] In equation (Z-1-1), Q 1 and Q 2 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms, but for improved solvent solubility, it is preferable that at least one is a trifluoromethyl group. m is 0, 1, 2, 3, or 4, but is particularly preferable to be 1. R 11a The hydrocarbyl group having 1 to 40 carbon atoms may include heteroatoms. As the heteroatom, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms, etc. are preferred, and oxygen atoms are more preferred. As for the hydrocarbyl group, it is particularly preferred to have 6 to 30 carbon atoms from the perspective of obtaining high resolution in fine pattern formation.

[0171] In equation (Z-1-1), R 11aThe hydrocarbyl group having 1 to 40 carbon atoms represented by may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples include alkyl groups having 1 to 40 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, and icosyl groups; Cyclic saturated hydrocarbyl groups having 3 to 40 carbon atoms, such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantyl methyl, norbornyl, norbornyl methyl, tricyclodecyl, tetracyclododecyl, tetracyclododecyl methyl, dicyclohexyl methyl, etc.; aryl groups having 6 to 40 carbon atoms, such as phenyl, 1-naphthyl, 2-naphthyl, 9-fluorenyl, tryptisenyl, etc.; aralkyl groups having 7 to 40 carbon atoms, such as benzyl, diphenylmethyl, etc.; Examples include 9,10-ethano-9,10-dihydroanthryl group, 6,13-ethano-6,13-dihydropentaxenyl group, and other aromatic ring-containing polycyclic hydrocarbyl groups having 7 to 40 carbon atoms; hydrocarbyl groups having 17 to 40 carbon atoms having a steroid backbone; and groups obtained by combining these.

[0172] In addition, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, or nitrogen atoms, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. Specific examples of hydrocarbyl groups containing heteroatoms include tetrahydrofuryl groups, methoxymethyl groups, ethoxymethyl groups, methylthiomethyl groups, acetamide methyl groups, trifluoroethyl groups, (2-methoxyethoxy)methyl groups, acetoxymethyl groups, 2-carboxy-1-cyclohexyl groups, 2-oxopropyl groups, 4-oxo-1-adamantyl groups, 3-oxocyclohexyl groups, etc.

[0173] In equation (Z-1-1), L a1 The bonds are single bonds, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, or carbamate bonds, but from the perspective of synthesis, ether bonds or ester bonds are preferred, and ester bonds are more preferred.

[0174] In equation (Z-2), R 12 is a hydrocarbyl group having 1 to 40 carbon atoms that may contain heteroatoms. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, R in formula (Z-1-1). 11aExamples of hydrocarbyl groups represented by [ ] can be given as those exemplified. In addition, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, or nitrogen atoms, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0175] In Equation (Z-3), x is 1, 2, or 3. y is 1, 2, 3, 4, or 5. z is 0, 1, 2, or 3, provided that 1 ≤ y + z ≤ 5. y is preferably 1, 2, or 3, and more preferably 2 or 3. z is preferably 0, 1, or 2.

[0176] In equation (Z-3), X BI is an iodine atom or a bromine atom. When x and / or y are 2 or greater, each X BI They may be identical or different.

[0177] In equation (Z-3), L 1 The group is a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a carbamate bond, or a saturated hydrocarbylene group having 1 to 6 carbon atoms, and a portion of the -CH2- of the hydrocarbylene group may be substituted by an ether bond or an ester bond. The saturated hydrocarbylene group may be straight, branched, or cyclic.

[0178] In equation (Z-3), L 2When x is 1, it is a hydrocarbylene group having 1 to 20 carbon atoms that may contain single bonds or heteroatoms, and when x is 2 or 3, it is a hydrocarbon group having 1 to 20 carbon atoms that may contain heteroatoms.

[0179] L 2 The hydrocarbylene group having 1 to 20 carbon atoms, represented by [], may be saturated or unsaturated and may be linear, branched, or cyclic. Specific examples include an alkanedyl group having 1 to 20 carbon atoms, such as a methanediyl group, an ethane-1,1-diyl group, an ethane-1,2-diyl group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group; Cyclopentanediyl, cyclohexanediyl, norbornandiyl, adamantandiyl, tricyclo[5.2.1.0 2,6 Examples include cyclic saturated hydrocarbylene groups having 3 to 20 carbon atoms, such as decandyl groups; unsaturated aliphatic hydrocarbylene groups having 2 to 20 carbon atoms, such as vinylene groups and propene-1,3-diyl groups; arylene groups having 6 to 20 carbon atoms, such as phenylene groups, naphthylene groups and anthracendiyl groups; aromatic ring-containing polycyclic hydrocarbylene groups having 7 to 20 carbon atoms, such as 9,10-ethano-9,10-dihydroanthracendiyl groups and 6,13-ethano-6,13-dihydropentacendyl groups; and groups obtained by combining these. L 2 The (x+1) hydrocarbon group having 1 to 20 carbon atoms represented by [the group] may be saturated or unsaturated, and may be straight, branched, or cyclic. Specific examples thereof include a group obtained by removing one or two more hydrogen atoms from the aforementioned specific example of a hydrocarbylene group having 1 to 20 carbon atoms.

[0180] In addition, the above hydrocarbylene group and (x+1) may have some or all of the hydrogen atoms of the hydrocarbon group substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and the above hydrocarbylene group and (x+1) may have some of the -CH2- of the hydrocarbon group substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc., and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0181] In equation (Z-3), L 3 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, carbonate bond, or carbamate bond.

[0182] In equation (Z-3), R 13 hydroxyl group, carboxyl group, fluorine atom, chlorine atom, bromine atom, pentafluorosulfanyl group, amino group, hydrocarbyl group having 1 to 20 carbon atoms, hydrocarbyloxy group having 1 to 20 carbon atoms, hydrocarbylthio group having 1 to 20 carbon atoms, hydrocarbylcarbonyl group having 2 to 20 carbon atoms, hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms, hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms, hydrocarbylsulfonyloxy group having 1 to 20 carbon atoms, -N(R 13A )(R 13B ), -N(R 13C )-C(=O)-R 13D or -N(R 13C )-C(=O)-OR 13DAnd, the corresponding hydrocarbyl group, hydrocarbyloxy group, hydrocarbylthio group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may include at least one selected from a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a hydroxyl group, an amino group, an ester bond, and an ether bond. R 13A and R 13B is, each independently, a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. R 13C is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may include a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. 13D is an aliphatic hydrocarbyl group having 1 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may include a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. The aliphatic hydrocarbyl group may be saturated or unsaturated and may be straight-chain, branched, or cyclic. The hydrocarbyl group, hydrocarbyloxy group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may be straight-chain, branched, or cyclic. When x and / or z are 2 or more, each R 13 They may be identical or different.

[0183] Among these, R 13 As, hydroxyl group, -N(R 13C )-C(=O)-R 13D , -N(R 13C )-C(=O)-OR 13DFluorine atoms, chlorine atoms, bromine atoms, methyl groups, methoxy groups, etc. are preferred.

[0184] In equation (Z-3), Rf 1 to Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They may combine to form a carbonyl group. In particular, Rf 3 and Rf 4 It is desirable that all of them are fluorine atoms.

[0185] Specific examples of the anion represented by formula (Z-1) include those shown below, but are not limited thereto. In addition, among the following formulas, Q 1 ...is the same as above, and Ac is an acetyl group.

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201]

[0202]

[0203]

[0204]

[0205]

[0206] Specific examples of anions represented by formula (Z-2) include those shown below, but are not limited to these.

[0207]

[0208]

[0209]

[0210]

[0211]

[0212]

[0213]

[0214]

[0215]

[0216]

[0217] Specific examples of the anion represented by formula (Z-3) include those shown below, but are not limited thereto. In addition, among the following formulas, X BI It is the same as above.

[0218]

[0219]

[0220]

[0221]

[0222]

[0223]

[0224]

[0225]

[0226]

[0227]

[0228]

[0229]

[0230]

[0231]

[0232]

[0233]

[0234]

[0235]

[0236]

[0237]

[0238]

[0239]

[0240]

[0241]

[0242]

[0243] Z -Other examples of anions represented by are paragraphs

[0076] and

[0106] of International Publication No. 2023 / 157455, paragraph

[0111] of International Publication No. 2024 / 24801, paragraphs

[0253] to

[0256] of International Publication No. 2024 / 43121, paragraphs

[0044] to

[0045] of International Publication No. 2024 / 57751, paragraphs

[0205] to

[0220] of International Publication No. 2024 / 122423, paragraphs

[0170] to

[0178] of Japanese Patent Publication No. 2023-123183, paragraphs

[0026] to

[0028] of Japanese Patent Publication No. 2024-62406, and paragraph

[0024] of Japanese Patent Publication No. 2024-62407.

[0022] to

[0025] , paragraphs

[0026] to

[0028] of Japanese Patent Publication No. 2024-62408, paragraphs

[0028] to

[0030] of Japanese Patent Publication No. 2024-68156, paragraphs

[0026] to

[0028] of Japanese Patent Publication No. 2024-68157, paragraphs

[0028] to

[0030] of Japanese Patent Publication No. 2024-68158, paragraphs

[0028] to

[0030] of Japanese Patent Publication No. 2024-68159, paragraphs

[0028] to

[0030] of Japanese Patent Publication No. 2024-72280, paragraphs

[0031] to

[0033] of Japanese Patent Publication No. 2024-72281, paragraphs

[0023] to

[0025] , Paragraphs

[0026] to

[0029] of Japanese Patent Publication No. 2024-77618, Paragraphs

[0020] to

[0021] of Japanese Patent Publication No. 2024-77619, Paragraphs

[0140] to

[0143] of Japanese Patent Publication No. 2024-80672, Paragraphs

[0023] to

[0025] of Japanese Patent Publication No. 2024-83303, Paragraphs

[0028] to

[0031] of Japanese Patent Publication No. 2024-83304, Paragraphs

[0030] to

[0033] of Japanese Patent Publication No. 2024-99500, Paragraphs

[0028] to

[0030] of Japanese Patent Publication No. 2024-99502,Paragraphs

[0030] to

[0032] of Japanese Patent Publication No. 2024-101557, Paragraphs

[0025] to

[0027] of Japanese Patent Publication No. 2024-102842, Paragraphs

[0033] to

[0035] of Japanese Patent Publication No. 2024-102843, Paragraphs

[0021] to

[0022] of Japanese Patent Publication No. 2024-127832, Paragraphs

[0169] to

[0172] of Japanese Patent Publication No. 2024-144354, Paragraphs

[0178] to

[0181] of Japanese Patent Publication No. 2024-144356, Paragraphs

[0040] to

[0143] of Japanese Patent Publication No. 2024-160436, Japan Examples include paragraphs

[0157] to

[0158] of Patent Publication No. 7247732, paragraphs

[0227] to

[0238] of Japanese Patent Publication No. 7446352, paragraphs

[0253] to

[0256] of Japanese Patent Publication No. 7466597, and paragraphs

[0309] to

[0312] of Japanese Patent Publication No. 7466782.

[0244] Specific examples of the sulfonium salt of the present invention include any combination of the aforementioned anion and cation.

[0245] As a method for synthesizing the sulfonium salt of the present invention, methods described in Japanese Patent Publication No. 2010-155824, Japanese Patent No. 7067271, etc., may be cited, but the above manufacturing methods are merely examples, and the method for manufacturing the sulfonium salt of the present invention is not limited to these.

[0246] Structural features of the sulfonium salt of the present invention include a fluoroalkanesulfonic acid anion that does not possess a polymerizable group and a sulfonium cation having an aromatic ring to which a pentafluorosulfanyl group and a hydrocarbyloxycarbonyl group are bonded. It is known that secondary electrons are emitted when EUV light is irradiated onto a base polymer or a photogenerative agent, and the pentafluorosulfanyl group bonded to the aromatic ring of the sulfonium cation is known as a strong electron-withdrawing group. In this regard, it is thought that the energy level of the LUMO in frontier orbital theory is lowered. Consequently, it becomes easier to accept the generated secondary electrons, the decomposition of the cation is promoted, and acid is efficiently generated. Since the hydrocarbyloxycarbonyl group bonded to the aromatic ring of the sulfonium cation possesses a lone pair of electrons derived from an ester bond, it can also be expected to function as an acid diffusion inhibitor by interacting with the protons of the generated acid. In addition, since the hydrocarbyloxycarbonyl group has electron-withdrawing properties, though not to the same extent as the pentafluorosulfanyl group, it is expected that the energy level of the LUMO in the frontier orbital theory will be lowered. Furthermore, since the hydrocarbyloxycarbonyl group has hydrolytic properties with respect to alkaline developers, the decomposition product of the cation in the exposure area exhibits affinity for the alkaline developer, thereby suppressing the development residue.

[0247] In the sulfonium salt of the present invention, the fluoroalkanesulfonic acid anion that does not have a polymerizable group preferably has one or more cyclic structures or iodine atoms. By introducing a cyclic structure, the exclusion volume is large, and it acts as a bulky substituent, thereby highly suppressing the diffusion of generated acids. When iodine atoms are introduced, since it is an element with a high absorption effect of EUV light, the amount of secondary electrons generated increases, which promotes the decomposition of cations and contributes to high sensitivity. Furthermore, since iodine atoms are elements with a large molecular weight, they highly suppress the diffusion of generated acids, similar to the case where a cyclic structure is introduced. In addition, since the cyclic structure and iodine atoms have resistance to alkaline developers, the film reduction of the pattern in the unexposed area is reduced. Although not as high as that of iodine atoms, fluorine atoms in the fluoroalkanesulfonic acid anion have a high absorption effect of EUV light; therefore, as the number of fluorine atoms increases, the amount of secondary electrons generated increases, which promotes the decomposition of cations and contributes to high sensitivity. When a cyclic structure or iodine atoms are introduced, there is concern regarding solubility in solvents, but since sufficient solvent solubility can be ensured by multiple fluorine atoms in the anion or pentafluorosulfanyl groups in the sulfonium cation, it dissolves uniformly in the solvent, thereby reducing concerns such as precipitation during storage. Due to these synergistic effects, the resist composition containing the sulfonium salt of the present invention has high sensitivity and low acid diffusivity, so it has excellent lithography performance such as LWR and CDU, and enables pattern formation resistant to pattern collapse, making it suitable for fine pattern formation.

[0248] The above sulfonium salt can be suitably used as a photogenerative agent.

[0249] [Chemical Amplification Resist Composition]

[0250] [(A) Mining Agent]

[0251] The chemical amplification resist composition of the present invention comprises, as an essential component, a photogenerative agent comprising a sulfonium salt represented by formula (1).

[0252] In the chemical amplification resist composition of the present invention, the content of a photogenerator comprising a sulfonium salt of component (A) is preferably 0.1 to 40 parts by mass and more preferably 0.5 to 30 parts by mass with respect to 80 parts by mass of the base polymer described below. It is desirable that the content of component (A) be within the above range because the sensitivity and resolution are good, and there is no risk of foreign matter occurring after development or peeling of the resist film. The photogenerator (A) may be used as a single type or in combination of two or more types.

[0253] [(B) Base Polymer]

[0254] The chemical amplification resist composition of the present invention may include a base polymer as component (B). As for the base polymer (B), it is preferable to include a repeating unit having an acid unstable group. The repeating unit containing the acid unstable group may be used as a single type or in combination of two or more types.

[0255] Specific examples of a repeating unit including the above acid instability group include a repeating unit represented by the following formula (a1) (hereinafter also referred to as repeating unit a1) and a repeating unit represented by the following formula (a2) (hereinafter also referred to as repeating unit a2).

[0256]

[0257] Among equations (a1) and (a2), R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0258] In equation (a1), X 1 It consists of single bonds, phenylene groups, naphthylene groups, or *-C(=O)-OX 11- and, the phenylene group or naphthylene group may be substituted with a hydroxyl group, a nitro group, a cyano group, a saturated hydrocarbyl group having 1 to 10 carbon atoms that may include a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms that may include a fluorine atom, or a halogen atom. X 11 is a saturated hydrocarbylene group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may include a hydroxyl group, an ether bond, an ester bond, or a lactone ring. * indicates a bond loss with a carbon atom of the main chain.

[0259] In equation (a2), X 2 is a single bond or *-C(=O)-O-. * indicates a bond loss with a carbon atom in the main chain. R 21 It is a halogen atom, a cyano group, a hydroxyl group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may include a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may include a heteroatom, a hydrocarbylcarbonyl group having 2 to 20 carbon atoms that may include a heteroatom, a hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms that may include a heteroatom, or a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may include a heteroatom. a1 is 0, 1, 2, 3, or 4, and preferably 0 or 1. When a1 is 2, 3, or 4, each R 21 They may be identical or different.

[0260] Among equations (a1) and (a2), AL 1 and AL 2 Each is an independent acid instability group. Specific examples of the above acid instability groups include those described in Japanese Patent Publication No. 2013-80033 or Japanese Patent Publication No. 2013-83821.

[0261] Typically, specific examples of the above acid instability group include those represented by the following formulas (AL-3) to (AL-5).

[0262]

[0263] (In the food, * is a connecting hand.)

[0264] Among equations (AL-3) and (AL-4), R L11 and R L12 Each is independently a hydrocarbyl group having 1 to 40 carbon atoms and may contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine atoms. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As for the hydrocarbyl group, it is preferable that it has 1 to 20 carbon atoms.

[0265] In formula (AL-3), a2 is an integer from 0 to 10, and 1, 2, 3, 4, or 5 is preferred.

[0266] In formula (AL-4), R L13 and R L14 Each is independently a hydrogen atom or a hydrocarbyl group having 1 to 20 carbon atoms, and may contain heteroatoms such as oxygen, sulfur, nitrogen, or fluorine atoms. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. Additionally, R L12 , R L13 and R L14 Any two of them may combine with each other to form a ring having 3 to 20 carbon atoms together with the carbon atom or the carbon atom and oxygen atom to which they combine. As for the ring, a ring having 4 to 16 carbon atoms is preferred, and a ring is particularly preferred.

[0267] In formula (AL-5), R L15 , R L16 and R L17Each is independently a hydrocarbyl group having 1 to 20 carbon atoms, and may contain heteroatoms such as oxygen, sulfur, nitrogen, or fluorine atoms. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. In addition, R L15 , R L16 and R L17 Any two of them may combine with each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded. As for the ring, a ring having 4 to 16 carbon atoms is preferred, and a ring is particularly preferred.

[0268] Other specific examples of the above acid instability group include those described in paragraphs

[0064] to

[0068] of Japanese Patent Publication No. 2023-123222 and those described in paragraphs

[0013] to

[0014] of Japanese Patent Publication No. 7492842. These utilize the generation of conjugated olefins or acrylic acid ester derivatives after the acid desorption reaction as the driving force for the reaction process.

[0269] Specific examples of the repeating unit a1 are those shown below, but are not limited thereto. In addition, among the following formulas, R A and AL 1 It is the same as above.

[0270]

[0271]

[0272]

[0273]

[0274] Specific examples of the repeating unit a2 are those shown below, but are not limited thereto. In addition, among the following formulas, R A and AL 2 It is the same as above.

[0275]

[0276]

[0277]

[0278] Another specific example of a repeating unit including the above acid instability group is a repeating unit represented by the following formula (a3) ​​(hereinafter also referred to as repeating unit a3).

[0279]

[0280] In formula (a3), b1 is 0 or 1. When b1 is 0, it is a benzene ring, and when b1 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable that b1 is a benzene ring of 0. b2 is 0, 1, 2, or 3 when b1 is 0, and 0, 1, 2, 3, 4, or 5 when b1 is 1. From the perspective of raw material procurement, it is preferable that b2 is 0, 1, 2, or 3, and more preferable that it is 0, 1, or 2.

[0281] In equation (a3), R A is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R A As for, it is preferable that it be a hydrogen atom or a methyl group, and more preferable that it be a hydrogen atom.

[0282] In equation (a3), X 3 is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-. * indicates a bond with a carbon atom in the main chain. Among these, a single bond, *-C(=O)-O- is preferred, and a single bond is more preferred.

[0283] In equation (a3), X 4 The group is a single bond, an aliphatic hydrocarbylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a combination thereof. Among these, from the perspective of raw material procurement, it is preferable that it be a single bond, a carbonyl group, or a sulfonyl group, and from the perspective of the polar group generated after the reaction, it is more preferable that it be a single bond or a carbonyl group.

[0284] In equation (a3), X 5 and X 6 Each is independently an oxygen atom or a sulfur atom. However, X 4 and X 6 The aromatic ring is bonded to an adjacent carbon atom. X 5 and X 6 They may be identical or different, but in terms of reactivity, X 5 and X 6 It is desirable that all of them be oxygen atoms.

[0285] In equation (a3), R 22 and R 23The hydrocarbyl group having 1 to 20 carbon atoms may each independently contain a hydrogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples include alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecyl, octadecyl, nonadecyl, and icosyl; Examples include cyclic saturated hydrocarbyl groups having 3 to 20 carbon atoms, such as cyclopropyl groups, cyclopentyl groups, cyclohexyl groups, cyclopropylmethyl groups, 4-methylcyclohexyl groups, cyclohexylmethyl groups, norbornyl groups, adamantyl groups; alkenyl groups having 2 to 20 carbon atoms, such as vinyl groups, 1-propenyl groups, 2-propenyl groups, butenyl groups, and hexenyl groups; cyclic unsaturated hydrocarbyl groups having 3 to 20 carbon atoms, such as cyclohexenyl groups; aryl groups having 6 to 20 carbon atoms, such as phenyl groups and naphthyl groups; aralkyl groups having 7 to 20 carbon atoms, such as benzyl groups, 1-phenylethyl groups, and 2-phenylethyl groups; and groups obtained by combining these. In addition, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0286] Also, R 22 and R 23The atoms may bond with each other to form a ring together with the carbon atoms to which they bond. Specific examples of the ring formed at this time include a cyclopropane ring, a cyclobutane ring, a cyclophenane ring, a cyclohexane ring, a norbornane ring, an adamantane ring, etc. In addition, some or all of the hydrogen atoms in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and some of the -CH2- in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0287] In equation (a3), R 24 is a halogen atom, a hydroxyl group, a cyano group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom, or -N(R 24A )(R 24B ) is. R 24A and R 24BEach is independently a hydrogen atom or a hydrocarbyl group having 1 to 6 carbon atoms. The halogen atom is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, and more preferably a fluorine atom or an iodine atom. The hydrocarbyl portion of the hydrocarbyl group and the hydrocarbyl group, hydrocarbyloxycarbonyl group, and hydrocarbylthio group may be saturated or unsaturated, and may be straight, branched, or cyclic. Specific examples thereof include R 22 and R 23 Examples of hydrocarbyl groups represented by [ ] and similar to those exemplified may be given. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. When b2 is 2 or more, each R 24 They may be identical or different.

[0288] Also, when b2 is 2 or greater, multiple R 24a. They may combine with each other to form a ring together with the carbon atom of the aromatic ring to which they are combined. Specific examples of the ring formed at this time include a cyclopropane ring, a cyclobutane ring, a cyclophenane ring, a cyclohexane ring, a norbornane ring, an adamantane ring, etc. In addition, some or all of the hydrogen atoms in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and some of the -CH2- in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0289] Specific examples of the repeating unit a3 are those shown below, but are not limited thereto. In addition, among the following formulas, R A ...is the same as above, and Me is a methyl group. In addition, the bonding positions of various substituents on the aromatic ring may be interchanged.

[0290]

[0291]

[0292]

[0293]

[0294]

[0295]

[0296]

[0297]

[0298]

[0299]

[0300]

[0301]

[0302]

[0303]

[0304]

[0305]

[0306]

[0307]

[0308]

[0309]

[0310]

[0311]

[0312]

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319]

[0320]

[0321]

[0322]

[0323]

[0324]

[0325]

[0326]

[0327]

[0328]

[0329]

[0330]

[0331]

[0332]

[0333]

[0334]

[0335]

[0336]

[0337]

[0338]

[0339]

[0340] The above polymer may include a repeating unit represented by the following formula (b1) (hereinafter also referred to as repeating unit b1) or a repeating unit represented by the following formula (b2) (hereinafter also referred to as repeating unit b2).

[0341]

[0342] Among equations (b1) and (b2), R A is, respectively, a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Y 1 is a single bond or *-C(=O)-O-. * indicates a bond loss with a carbon atom in the main chain. R 31R is a group having 1 to 20 carbon atoms comprising at least one structure selected from a hydrogen atom, or a hydroxyl group other than a phenolic hydroxyl group, a cyano group, a carbonyl group, a carboxyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, and a carboxylic acid anhydride (-C(=O)-OC(=O)-). 32 is a halogen atom, a carboxyl group, a nitro group, a cyano group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom. When c2 is 2, 3, or 4, each R 32 and may be the same or different. c1 is 1, 2, 3, or 4. c2 is 0, 1, 2, 3, or 4. Provided that 1 ≤ c1 + c2 ≤ 5.

[0343] Specific examples of the repeating unit b1 are those shown below, but are not limited thereto. In addition, among the following formulas, R A It is the same as above.

[0344]

[0345]

[0346]

[0347]

[0348]

[0349]

[0350]

[0351]

[0352]

[0353]

[0354]

[0355]

[0356]

[0357]

[0358]

[0359]

[0360] Specific examples of the repeating unit b2 are those shown below, but are not limited thereto. In addition, among the following formulas, R A It is the same as above.

[0361]

[0362]

[0363]

[0364]

[0365]

[0366] As for the repeating unit b1 or b2, in ArF lithography, it is particularly desirable to have a lactone ring as a polar group, and in KrF lithography, EB lithography and EUV lithography, it is desirable to have a phenol group.

[0367] The above polymer may include at least one selected from the repeating unit represented by the following formula (c1) (hereinafter also referred to as repeating unit c1), the repeating unit represented by the following formula (c2) (hereinafter also referred to as repeating unit c2), the repeating unit represented by the following formula (c3) (hereinafter also referred to as repeating unit c3), the repeating unit represented by the following formula (c4) (hereinafter also referred to as repeating unit c4), and the repeating unit represented by the following formula (c5) (hereinafter also referred to as repeating unit c5).

[0368]

[0369] Among formulas (c1) to (c5), R A is, respectively, a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z 1 It is a phenylene group that may have a single bond or a substituent. Z 2 is a single bond, **-C(=O)-OZ 21 -, **-C(=O)-N(H)-Z 21 - or **-OZ 21 -is. Z 21 is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by a combination thereof, and may include a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. Z 3 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. Z 4 is a single bond, or a divalent group obtained by combining an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, or a combination thereof, and may include a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. Z 5 are, respectively, a single bond, a phenylene group that may have a substituent, a naphthylene group that may have a substituent, and *-C(=O)-OZ 51- or *-C(=O)-N(R)-Z 51 -is. Z 51 is an aliphatic hydrocarbylene group having 1 to 10 carbon atoms, a phenylene group, or a naphthylene group, and the aliphatic hydrocarbylene group may include a halogen atom, a hydroxyl group, an ether bond, an ester bond, or a lactone ring. R is a hydrocarbylene group having 1 to 10 carbon atoms that may include a hydrogen atom or a heteroatom.

[0370] Z 6 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. Z 7 Silver, each independently single bond, ***-Z 71 -C(=O)-O-, ***-C(=O)-N(R)-Z 71 - or ***-OZ 71 -is. Z 71 It is a hydrocarbylene group having 1 to 20 carbon atoms that may contain heteroatoms. R is the same as above. Z 8 Silver, each independently single bond, ****-Z 81 -C(=O)-O-, ****-C(=O)-N(R)-Z 81 - or ****-OZ 81 -is. Z 81 It is a hydrocarbylene group having 1 to 20 carbon atoms that may contain heteroatoms. R is the same as above. Z 9 is, single bond, methylene group, ethylene group, phenylene group, fluorinated phenylene group, phenylene group substituted with trifluoromethyl, *-C(=O)-OZ 91 -, *-C(=O)-N(R)-Z 91 - or *-OZ 91 -is. Z 91is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a phenylene group substituted with a trifluoromethyl group, and may include a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. R is the same as above. * indicates a loss of bond with a carbon atom of the main chain. ** is Z 1 Indicates the bonding loss with. *** is Z 6 Indicates the bond with. **** is Z 7 It represents the bonding hand with.

[0371] Z 21 , Z 51 and Z 91 The aliphatic hydrocarbylene group represented by may be linear, branched, or cyclic, and specific examples include a methanediyl group, an ethane-1,1-diyl group, an ethane-1,2-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-1,3-diyl group, a propane-2,2-diyl group, a butane-1,1-diyl group, a butane-1,2-diyl group, a butane-1,3-diyl group, a butane-1,4-diyl group, a 1,1-dimethylethane-1,2-diyl group, a pentane-1,5-diyl group, a 2-methylbutane-1,2-diyl group, and a hexane-1,6-diyl group; Examples include cycloalkanedyl groups such as cyclopropane diyl group, cyclobutane diyl group, cyclopentane diyl group, and cyclohexanedyl group; and groups obtained by combining these.

[0372] Z 71 and Z 81 The hydrocarbylene group, which may contain a heteroatom represented by, may be saturated or unsaturated and may be straight, branched, or cyclic. Specific examples thereof are shown below, but are not limited thereto.

[0373]

[0374] (In the formula, dashed lines indicate joint loss.)

[0375] In equation (c1), R 41 and R 42... is a hydrocarbyl group having 1 to 20 carbon atoms, each of which may independently contain a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples include: an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a tert-butyl group; a cyclic saturated hydrocarbyl group having 3 to 20 carbon atoms, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclopropylmethyl group, a 4-methylcyclohexyl group, a cyclohexylmethyl group, a norbornyl group, or adamantyl group; and an alkenyl group having 2 to 20 carbon atoms, such as a vinyl group, a 1-propenyl group, a 2-propenyl group, a butenyl group, or a hexenyl group. Examples include cyclic unsaturated hydrocarbyl groups having 3 to 20 carbon atoms, such as cyclohexenyl groups; aryl groups having 6 to 20 carbon atoms, such as phenyl groups, naphthyl groups, and thienyl groups; aralkyl groups having 7 to 20 carbon atoms, such as benzyl groups, 1-phenylethyl groups, and 2-phenylethyl groups; and groups obtained by combining these, but aryl groups are preferred. In addition, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, or nitrogen atoms, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0376] Also, R 41 and R 42 They may combine with each other to form a ring together with the sulfur atom to which they combine. In this case, specific examples of the above ring include those represented by the following formula.

[0377]

[0378] (In the formula, the dashed line is Z 4 It is a combined hand with.)

[0379] Specific examples of the cation of the repeating unit c1 are those shown below, but are not limited thereto. In addition, among the following formulas, R A It is the same as above.

[0380]

[0381]

[0382]

[0383]

[0384]

[0385]

[0386]

[0387]

[0388]

[0389]

[0390] In equation (c1), M -is a non-nucleophilic counterion. As the above non-nucleophilic counterion, halide ions, sulfonate anions, imidate anions, and methide anions are preferred. Specific examples of the above halide ions include chloride ions, bromide ions, etc. Specific examples of the above sulfonate anions (sulfonate ions) include fluoroalkylsulfonate ions such as trilate ions, 1,1,1-trifluoroethanesulfonate ions, and nonafluorobutanesulfonate ions; arylsulfonate ions such as tosylate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, and 1,2,3,4,5-pentafluorobenzenesulfonate ions; and alkylsulfonate ions such as mesylate ions and butanesulfonate ions. Specific examples of the above imidate anion (imide ion) include bis(trifluoromethylsulfonyl)imide ion, bis(perfluoroethylsulfonyl)imide ion, bis(perfluorobutylsulfonyl)imide ion, etc. Specific examples of the above methide anion (methide ion) include tris(trifluoromethylsulfonyl)methide ion, tris(perfluoroethylsulfonyl)methide ion, etc.

[0391] Other examples of the above-mentioned non-nucleophilic counter-ions include anions represented by any of formulas (Z-1) to (Z-3).

[0392] As another example of the above-mentioned non-nucleophilic counterion, an anion represented by the following formula (M-1) or (M-2) is also preferred.

[0393]

[0394] In equation (M-1), R M1 and R M2 is a hydrocarbyl group having 1 to 40 carbon atoms, which may each independently contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, R in formula (Z-1-1). 11aExamples of hydrocarbyls represented by can be cited as being similar to those exemplified. R M1 and R M2 Preferably, it is a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R M1 and R M2 They combine with each other, and the groups they combine with (-CF2-SO2-N - It may form a ring with -SO2-CF2-), and in this case, R M1 and R M2 As for the groups obtained by combining with each other, a fluorinated ethylene group or a fluorinated propylene group is preferred.

[0395] In equation (M-2), R M3 , R M4 and R M5 is a hydrocarbyl group having 1 to 40 carbon atoms, which may each independently contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, R in formula (Z-1-1). 11a Examples of hydrocarbyls represented by can be cited as being similar to those exemplified. R M3 , R M4 and R M5 Preferably, it is a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R M3 and R M4 a, combining with each other, the groups that combine (-CF2-SO2-C - It may form a ring with -SO2-CF2-), and in this case, R M3 and R M4 As for the groups obtained by combining with each other, a fluorinated ethylene group or a fluorinated propylene group is preferred.

[0396] As the above non-nucleophilic counterion, additionally, the anion of a bissulfonic acid described in Japanese Patent Publication No. 2015-206932, the anion of a sulfonamide or sulfonimide in which one side is a sulfonic acid and the other side is different from this described in International Publication No. 2020 / 158366, and the anion of a carboxylic acid in which one side is a sulfonic acid and the other side is a carboxylic acid described in Japanese Patent Publication No. 2015-24989 may be used.

[0397] Among formulas (c2) and (c3), d1 and d2 are each independently 0, 1, 2 or 3, but 1 is preferred.

[0398] In equation (c4), e1 is 0 or 1. e2 is 0, 1, 2, 3, or 4. e3 is 0, 1, 2, 3, or 4. However, when e1 is 0, 0 ≤ e2 + e3 ≤ 4, and when e1 is 1, 0 ≤ e2 + e3 ≤ 6.

[0399] Among equations (c2), (c3) and (c4), L 1 The bonds are single bonds, ether bonds, ester bonds, carbonyl groups, sulfonic acid ester bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Among these, from the perspective of synthesis, ether bonds, ester bonds, and carbonyl groups are preferred, and ester bonds and carbonyl groups are more preferred.

[0400] In equation (c2), Rf 11 and Rf 12 Each is independently a fluorine atom or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. Among these, Rf 11 and Rf 12 As such, in order to increase the acid strength of the generated acid, it is desirable that all of them be fluorine atoms. Rf 13 and Rf 14 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. Among these, to improve solvent solubility, Rf 13 and Rf 14It is preferable that at least one of them is a trifluoromethyl group.

[0401] In Equation (c3), Rf 15 and Rf 16 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. provided that all Rf 15 and Rf 16 It does not simultaneously become a hydrogen atom. Among these, to improve solvent solubility, Rf 15 and Rf 16 It is preferable that at least one of them is a trifluoromethyl group.

[0402] In Equation (c4), Rf 17 It is a fluorine atom, a C1 to C6 fluorinated alkyl group, a C1 to C6 fluorinated alkoxy group, a C1 to C6 fluorinated alkylthio group, or a pentafluorosulfanyl group. Rf 17 As such, a fluorine atom, a trifluoromethyl group, a difluoromethyl group, a trifluoromethoxy group, a difluoromethoxy group, a trifluoromethylthio group, or a difluoromethylthio group is preferred, and a fluorine atom, a trifluoromethyl group, or a trifluoromethoxy group is more preferred. When e2 is 2, 3, or 4, each Rf 17 They may be identical or different.

[0403] In equation (c4), R 43 It is a hydrocarbyl group having 1 to 20 carbon atoms that may include halogen atoms other than fluorine atoms or heteroatoms. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, in the explanation of Formula (1), R 1 to R 3 Hydrocarbyls represented by may include, but are not limited to, those exemplified. Additionally, when e3 is 2, 3, or 4, each R 43 They may be identical or different.

[0404] Also, when e3 is 2, 3, or 4, multiple R 43 These may combine with each other to form a ring together with the carbon atom to which they are bonded. Specific examples of the ring formed at this time include a cyclopropane ring, a cyclobutane ring, a cyclophenane ring, a cyclohexane ring, a norbornane ring, an adamantane ring, etc. In addition, some or all of the hydrogen atoms in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and some of the -CH2- in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0405] Specific examples of the anion of the repeating unit c2 are those shown below, but are not limited thereto. In addition, among the following formulas, R A is the same as above, and Me is a methyl group.

[0406]

[0407]

[0408]

[0409]

[0410]

[0411]

[0412]

[0413]

[0414]

[0415]

[0416]

[0417]

[0418]

[0419] Other specific examples of repetition unit c2 include those described in paragraphs

[0043] to

[0044] of International Publication No. 2024 / 176672, paragraphs

[0067] to

[0070] of International Publication No. 2024 / 176701, paragraphs

[0057] to

[0058] of International Publication No. 2024 / 190386, paragraphs

[0020] to

[0023] of Japanese Patent Publication No. 2024-103465, paragraphs

[0067] to

[0070] of Japanese Patent Publication No. 2024-120703, and paragraphs

[0075] to

[0084] of Japanese Patent No. 7520258.

[0420] Specific examples of the anion of the repeating unit c3 are those shown below, but are not limited thereto. In addition, among the following formulas, R A It is the same as above.

[0421]

[0422]

[0423]

[0424]

[0425]

[0426]

[0427]

[0428]

[0429]

[0430]

[0431]

[0432] Specific examples of the anion of the repeating unit c4 are those shown below, but are not limited thereto. In addition, among the following formulas, R A It is the same as above.

[0433]

[0434]

[0435]

[0436]

[0437]

[0438]

[0439]

[0440]

[0441]

[0442]

[0443]

[0444]

[0445]

[0446]

[0447]

[0448]

[0449]

[0450] Specific examples of the anion of the repeating unit c5 are those shown below, but are not limited thereto. In addition, among the following formulas, R A It is the same as above.

[0451]

[0452] Among formulas (c2) to (c5), A + is an onium cation. Examples of the above onium cation include sulfonium cations, iodonium cations, ammonium cations, etc., but it is preferable that it be a sulfonium cation or an iodonium cation. Specific examples of the above sulfonium cation include those exemplified as specific examples of cations of sulfonium salts represented by formula (1), those described in paragraphs

[0102] to

[0125] of Japanese Patent Publication No. 2024-3744, those described in paragraphs

[0044] to

[0049] of International Publication No. 2024 / 128017, and those described in paragraphs

[0035] to

[0046] of Patent Publication No. 7491173, but are not limited thereto.

[0453] In addition, as the above sulfonium cation, a sulfonium cation represented by the following formula (sulfo-1) is also preferred.

[0454]

[0455] In formula (sulfo-1), f1 is 0 or 1. When f1 is 0, it is a benzene ring, and when f1 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable that f1 is a benzene ring with a value of 0. f2 is 0 or 1. When f2 is 0, it is a benzene ring, and when f2 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable that f2 is a benzene ring with a value of 0. f3 is 0 or 1. When f3 is 0, it is a benzene ring, and when f3 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable that f3 is a benzene ring with a value of 0.

[0456] In formula (sulfo-1), f4 is 0, 1, 2, 3, or 4. As the number of iodine atoms in the cation structure increases, absorption for EUV, in particular, increases, but solvent solubility becomes insufficient, and there is a risk of precipitation in the resist composition; therefore, it is preferable that f4 is 0, 1, 2, or 3, and more preferable that it is 0, 1, or 2.

[0457] In formula (sulfo-1), f5 is 0, 1, 2, 3, or 4. From the perspective of raw material procurement, f5 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2. f6 is 0, 1, 2, 3, 4, 5, or 6. From the perspective of raw material procurement, f6 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2. f7 is 0, 1, 2, 3, 4, 5, or 6. From the perspective of raw material procurement, f7 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2.

[0458] In formula (sulfo-1), f8 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable that f8 is 0 or 1. f9 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable that f9 is 0 or 1. f10 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable that f10 is 0 or 1.

[0459] In formula (sulfo-1), f11 is 0 or 1. When f11 is 0, it is a benzene ring, and when f11 is 1, it is a naphthalene ring, but from the perspective of solvent solubility, it is preferable for f11 to be a benzene ring of 0.

[0460] In formula (sulfo-1), f12 is 0, 1, 2, 3, or 4. As the number of iodine atoms in the cation structure increases, absorption of EUV, in particular, increases, but solvent solubility becomes insufficient, and there is a risk of precipitation in the resist composition; therefore, it is preferable that f12 is 0, 1, 2, or 3, and more preferable that it is 0, 1, or 2.

[0461] In formula (sulfo-1), f13 is 0, 1, or 2. From the perspective of raw material procurement, it is preferable that f13 is 0 or 1. f14 is 0, 1, or 2. From the perspective of synthesis, it is preferable that f14 is 0 or 1.

[0462] However, when f1 is 0, 0 ≤ f6 + f9 ≤ 4, and when f1 is 1, 0 ≤ f6 + f9 ≤ 6. When f2 is 0, 0 ≤ f7 + f10 ≤ 4, and when f2 is 1, 0 ≤ f7 + f10 ≤ 6. When f3 is 0, 1 ≤ f4 + f5 + f8 + f14 ≤ 4, and when f3 is 1, 1 ≤ f4 + f5 + f8 + f14 ≤ 6. When f11 is 0, 0 ≤ f12 + f13 ≤ 4, and when f11 is 1, 0 ≤ f12 + f13 ≤ 6. Also, f4 + f12 ≥ 1.

[0463] Among formulas (sulfo-1), R F1 to R F3 Each is independently a fluorine atom, a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms, a fluorinated saturated hydrocarbyloxy group having 1 to 6 carbon atoms, or a fluorinated saturated hydrocarbylthio group having 1 to 6 carbon atoms. Among these, it is preferred to be a trifluoromethyl group, a trifluoromethoxy group, or a trifluorothiomethoxy group. When f5 is 2, 3, or 4, each R F1 may be the same or different. When f6 is 2, 3, 4, 5, or 6, each R F2 may be the same or different. When f7 is 2, 3, 4, 5, or 6, each R F3 They may be identical or different.

[0464] Among formulas (sulfo-1), R ct1 to R ct4 is a hydrocarbyl group having 1 to 20 carbon atoms that may contain a halogen atom other than an iodine atom and a fluorine atom, a nitro group, a cyano group, or a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom. The hydrocarbyl portion of the hydrocarbyl group, the hydrocarbyloxy group, and the hydrocarbylthio group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, in the explanation of Formula (1), R1 to R 3 Examples of hydrocarbyl groups represented as such can be given as those exemplified. In addition, some or all of the hydrogen atoms of the hydrocarbyl portion of the hydrocarbyl group, hydrocarbyloxy group, and hydrocarbylthio group may be substituted with a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0465] Also, when f8 is 2, 2 R ct1 They may be identical or different from each other, and 2 Rs ct1 These may bond with each other to form a ring together with the carbon atom they bond to. When f9 is 2, 2 R ct2 They may be identical or different from each other, and 2 R ct2 They may bond with each other to form a ring together with the carbon atom they bond to. When f10 is 2, 2 R ct3 They may be identical or different from each other, and 2 Rs ct3 These may bond with each other to form a ring together with the carbon atom they bond to. When f13 is 2, 2 R ct4 They may be identical or different from each other, and 2 R ct4They may bond with each other to form a ring together with the carbon atom to which they bond. Specific examples of the ring formed at this time include a cyclopropane ring, a cyclobutane ring, a cyclophenane ring, a cyclohexane ring, a norbornane ring, an adamantane ring, etc. In addition, some or all of the hydrogen atoms in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and some of the -CH2- in the ring may be substituted with a group containing heteroatoms such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, may include a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0466] In addition, S in the sulfonium cation represented by the formula (sulfo-1) + Direction rings that directly bind to each other combine to form S + A ring may be formed together with. In this case, specific examples of the structure of the ring include those represented by the following formula.

[0467]

[0468] (In the formula, the dashed line is a connecting hand.)

[0469] Among the formula (sulfo-1), L B and L C Each is independently a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonate amide bond, carbonate bond, or carbamate bond. Among these, L B As such, it is preferable that it be a single bond, an ether bond, an ester bond, or a sulfonic acid ester bond, and more preferable that it be an ester bond or a sulfonic acid ester bond. L CAs such, it is preferable that it be a single bond, an ether bond, or an ester bond, and more preferable that it be a single bond.

[0470] Among formulas (sulfo-1), X L The hydrocarbylene group having 1 to 40 carbon atoms may include a single bond or a heteroatom. The hydrocarbylene group may be straight, branched, or cyclic, and specific examples include an alkanedyl group, a cyclic saturated hydrocarbylene group, an arylene group, etc. Specific examples of the heteroatom include an oxygen atom, a nitrogen atom, a sulfur atom, etc.

[0471] X L Specific examples of hydrocarbylene groups having 1 to 40 carbon atoms that may include a heteroatom represented by are shown below, but are not limited thereto. In addition, in the following formulas, * represents L B and L C It is a combined hand.

[0472]

[0473]

[0474]

[0475]

[0476] Among these, X L -0 to X L -22, X L -29 to X L -34 and X L -47 to X L -61 is desirable.

[0477] As for the sulfonium cation represented by the formula (sulfo-1), it is preferable to represent it by the following formula (sulfo-1-1).

[0478]

[0479] (among the formulas, f4 to f10, f12 to f14, R F1 to RF3 , R ct1 to R ct4 , L B , L C and X L ...is the same as above.)

[0480] As for the sulfonium cation represented by the formula (sulfo-1-1), it is preferable to represent it by the following formula (sulfo-1-2).

[0481]

[0482] (among the formulas, f4 to f10, R F1 to R F3 and R ct1 to R ct3 ...is the same as above.)

[0483] Specific examples of the sulfonium cation represented by the formula (sulfo-1) include those shown below, but are not limited thereto. In addition, in the following formulas, Me is a methyl group.

[0484]

[0485]

[0486]

[0487]

[0488]

[0489]

[0490]

[0491]

[0492]

[0493]

[0494]

[0495]

[0496]

[0497]

[0498]

[0499]

[0500]

[0501]

[0502]

[0503]

[0504]

[0505]

[0506]

[0507]

[0508]

[0509]

[0510]

[0511]

[0512] Specific examples of the above iodine cations include those described in paragraph

[0181] of Japanese Patent Publication No. 2024-259, but are not limited thereto.

[0513] Specific examples of the above ammonium cation include those represented by the following formula (am-1).

[0514]

[0515] In the equation (am-1), R ct5 to R ct8 It is a hydrocarbyl group having 1 to 40 carbon atoms, each of which may independently contain a heteroatom. Also, R ct5 and R ct6These may combine with each other to form a ring together with the nitrogen atom to which they combine. As a specific example of the above hydrocarbyl group, R in the explanation of Formula (1) 1 to R 3 Examples of hydrocarbilic groups indicated as such can be cited as those exemplified.

[0516] Specific examples of the ammonium cation represented by formula (am-1) include those shown below, but are not limited thereto.

[0517]

[0518] As specific structures of repeating units c1 to c5, any combination of the aforementioned anions and cations may be cited.

[0519] Among repeating units c1 to c5, repeating units c2 to c5 are preferred in terms of controlling acid diffusion, repeating units c2, c4, and c5 are more preferred in terms of acid strength of generated acid, and repeating unit c2 is even more preferred in terms of solvent solubility.

[0520] The above polymer may include a repeating unit (hereinafter also referred to as repeating unit d) having a structure in which a hydroxyl group is protected by an acid unstable group. As for the repeating unit d, it is not particularly limited as long as it has one or more structures in which a hydroxyl group is protected and the protecting group is decomposed by the action of an acid to generate a hydroxyl group, but it is preferred to be represented by the following formula (d1).

[0521]

[0522] In equation (d1), R A is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 51 It is a (g+1) valence hydrocarbon group having 1 to 30 carbon atoms that may contain heteroatoms. 52 is an acid instability group. g is 1, 2, 3, or 4.

[0523] In equation (d1), R 52 The acid instability group denoted by must be one that deprotects upon the action of the acid and generates a hydroxyl group. R 52 The structure is not particularly limited, but an acetal structure, a ketal structure, a hydrocarbyloxycarbonyl group, a hydrocarbyloxymethyl group represented by the following formula (d2), etc. are preferred, and in particular, a hydrocarbyloxymethyl group represented by the following formula (d2) is preferred.

[0524]

[0525] (In the formula, * indicates a bond. R 53 is a hydrocarbyl group having 1 to 15 carbon atoms.

[0526] R 52 Specific examples of the acid instability group represented by , the hydrocarbyloxymethyl group represented by formula (d2), and the repeating unit d include those exemplified in the description of the repeating unit d in Japanese Patent Publication No. 2020-111564.

[0527] The above polymer may include a repeating unit e derived from indene, benzofuran, benzothiophene, acenaphtylene, chromone, coumarin, norbornadiene, or derivatives thereof. Specific examples of monomers imparting the repeating unit e include those shown below, but are not limited thereto.

[0528]

[0529] The above polymer may include repeating units f derived from indan, vinylpyridine, or vinylcarbazole.

[0530] Among the above polymers, the content ratio of repeating units a1, a2, a3, b1, b2, c1 to c5, d, e, and f is preferably 0 <a1≤0.8, 0≤a2≤0.8, 0≤a3≤0.6, 0≤b1≤0.6, 0≤b2≤0.6, 0≤c1≤0.4, 0≤c2≤0.4, 0≤c3≤0.4, 0≤c4≤0.4, 0≤c5≤0.4, 0≤d≤0.5, 0≤e≤0.3 및 0≤f≤0.3이고, 보다 바람직하게는 0<a1≤0.7, 0≤a2≤0.7, 0≤a3≤0.5, 0≤b1≤0.5, 0≤b2≤0.5, 0≤c1≤0.3, 0≤c2≤0.3, 0≤c3≤0.3, 0≤c4≤0.3, 0≤c5≤0.3, 0≤d≤0.3, 0≤e≤0.3 및 0≤f≤0.3이다. 단, a1+a2+a3+b1+b2+c1+c2+c3+c4+d+e+f≤1.0이다.

[0531] The weight average molecular weight (Mw) of the above polymer is preferably 1,000 to 500,000, and more preferably 3,000 to 100,000. When Mw is in this range, sufficient etching resistance is obtained, and there is no concern about a decrease in resolution due to the inability to secure a difference in dissolution rate before and after exposure. In addition, in the present invention, Mw is a polystyrene equivalent measurement value by gel permeation chromatography (GPC) using tetrahydrofuran (THF) or N,N-dimethylformamide (DMF) as a solvent.

[0532] Regarding the molecular weight distribution (Mw / Mn) of the above polymer, since the influence of Mw / Mn tends to increase as the pattern rule becomes finer, it is preferable that Mw / Mn be narrowly dispersed to 1.0 to 2.0 in order to obtain a resist composition suitable for use with fine pattern dimensions. Within the above range, there is a small amount of low molecular weight or high molecular weight polymer, and there is no risk of foreign matter being visible on the pattern or the shape of the pattern deteriorating after exposure.

[0533] As a method for synthesizing the above polymer, for example, a method may be used in which a monomer imparting the aforementioned repeating unit is heated in an organic solvent with a radical polymerization initiator and polymerized.

[0534] Specific examples of organic solvents used during polymerization include toluene, benzene, THF, diethyl ether, dioxane, cyclohexane, cyclopentane, methyl ethyl ketone (MEK), propylene glycol monomethyl ether acetate (PGMEA), γ-butyrolactone (GBL), etc. Specific examples of the polymerization initiator include 2,2'-azobis(isobutyronitrile) (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl-2,2-azobis(2-methylpropionate), 1,1'-azobis(1-acetoxy-1-phenylethane), benzoyl peroxide, lauroyl peroxide, etc. The amount of these initiators added is preferably 0.01 to 25 mol% with respect to the total amount of monomers to be polymerized. The reaction temperature is preferably 50 to 150°C, and more preferably 60 to 100°C. The reaction time is preferably 2 to 24 hours, and more preferably 2 to 12 hours from the perspective of production efficiency.

[0535] The polymerization initiator may be added to the monomer solution and supplied to the reaction vessel, or the initiator solution may be prepared separately from the monomer solution and supplied to the reaction vessel independently. From the perspective of quality control, it is preferable to prepare the monomer solution and the initiator solution independently and add them dropwise, as there is a possibility that the polymerization reaction may proceed due to radicals generated from the initiator during the waiting time, thereby forming the superpolymer itself. The acid unstable group may be used as is upon introduction into the monomer, or it may be protected or partially protected after polymerization. Additionally, known chain transfer agents such as dodecyl mercaptan or 2-mercaptoethanol may be used in combination to adjust the molecular weight. In this case, the amount of these chain transfer agents added is preferably 0.01 to 20 mol% relative to the total amount of monomers to be polymerized.

[0536] In the case of monomers containing hydroxyl groups, the hydroxyl groups may be substituted with acetal groups that are easily deprotected by acids such as ethoxyethoxy groups during polymerization and deprotected with a weak acid and water after polymerization, or they may be substituted with acetyl groups, formyl groups, pivaloyyl groups, etc. and alkaline hydrolysis may be performed after polymerization.

[0537] When copolymerizing hydroxystyrene or hydroxyvinylnaphthalene, hydroxystyrene or hydroxyvinylnaphthalene and other monomers may be heated polymerized by adding a radical polymerization initiator in an organic solvent, but acetoxystyrene or acetoxyvinylnaphthalene may be used to deprotect the acetoxy groups by alkali hydrolysis after polymerization to obtain polyhydroxystyrene or hydroxypolyvinylnaphthalene.

[0538] Specific examples of the base during alkaline hydrolysis include water ammonia, triethylamine, etc. In addition, the reaction temperature is preferably -20 to 100°C, more preferably 0 to 60°C. The reaction time is preferably 0.2 to 100 hours, more preferably 0.5 to 20 hours.

[0539] In addition, the amount of each monomer in the above monomer solution can be appropriately set, for example, to a desirable content ratio of the repeating unit described above.

[0540] The polymer obtained by the above manufacturing method may be treated as a final product by the reaction solution obtained by the polymerization reaction, or as a final product by the powder obtained through a purification process such as a reprecipitation method in which the polymer solution is added to a solvent and a powder is obtained. However, from the perspective of work efficiency and quality stabilization, it is preferable to treat the polymer solution obtained by the purification process, dissolved in a solvent, as the final product.

[0541] Specific examples of solvents used at that time include ketones such as cyclohexanone and methyl-2-n-pentyl ketone, as described in paragraphs

[0144] to

[0145] of Japanese Patent Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; and ethers such as propylene glycol monomethyl ether (PGME), ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether. Examples include esters such as PGMEA, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as GBL; alcohols such as diacetone alcohol (DAA); high-boiling point alcohol-based solvents such as diethylene glycol, propylene glycol, glycerin, 1,4-butanediol, and 1,3-butanediol; and mixed solvents thereof.

[0542] Among the polymer solutions, the concentration of the polymer is preferably 0.01 to 30 mass%, and more preferably 0.1 to 20 mass%.

[0543] It is desirable to filter the above reaction solution or polymer solution. By filtering, foreign substances or gels that may cause defects can be removed, and it is effective in terms of quality stabilization.

[0544] The material of the filter used for the above filter filtration may be a fluorocarbon-based, cellulose-based, nylon-based, polyester-based, or hydrocarbon-based material; however, for the filtration process of the resist composition, a filter formed from a fluorocarbon-based material called so-called Teflon (registered trademark), a hydrocarbon-based material such as polyethylene or polypropylene, or nylon is preferred. The pore diameter of the filter can be appropriately selected to match the target cleanliness, but is preferably 100 nm or less, and more preferably 20 nm or less. In addition, one type of filter may be used alone, or multiple filters may be used in combination. Regarding the filtration method, passing the solution through only once is acceptable, but it is more preferable to circulate the solution and perform filtration multiple times. The filtration process may be performed in any sequence or number of times during the polymer manufacturing process, but it is preferable to filter the reaction solution after the polymerization reaction, the polymer solution, or both.

[0545] (B) The base polymer may be used as a single type, or two or more types with different composition ratios, Mw and / or Mw / Mn may be used in combination. In addition, (B) the base polymer may include, in addition to the above polymer, a hydrogenated ring-opening metathesis polymer, and regarding this, the one described in Japanese Patent Publication No. 2003-66612 may be used.

[0546] [(C) Organic solvent]

[0547] The chemical amplification resist composition of the present invention may include an organic solvent as component (C). As for the organic solvent (C), it is not particularly limited as long as it is capable of dissolving each of the aforementioned components and each of the components described below. Specific examples of such organic solvents include ketones such as cyclopentanone, cyclohexanone, and methyl-2-n-pentyl ketone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; keto alcohols such as DAA; and ethers such as PGME, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether. Examples include esters such as PGMEA, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as GBL; and mixed solvents thereof.

[0548] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, cyclohexanone, GBL, ethyl lactate, DAA, and mixtures thereof are preferred, as they have particularly excellent solubility of the base polymer of component (B).

[0549] In the chemical amplification resist composition of the present invention, the content of (C) organic solvent is preferably 200 to 5000 parts by mass and more preferably 400 to 3500 parts by mass with respect to 80 parts by mass of (B) base polymer. (C) organic solvent may be used alone or two or more types may be mixed.

[0550] [(D) Quencher]

[0551] The chemical amplification resist composition of the present invention may include a quencher as component (D). Furthermore, in the present invention, a quencher is a material for forming a desired pattern by capturing a strong acid generated from a photogenerative agent in the chemical amplification resist composition to prevent diffusion to an unexposed area. Furthermore, a strong acid refers to an acid having sufficient acidity to cause a deprotection reaction of an acid unstable group.

[0552] (D) Specific examples of quenchers include onium salts represented by the following formulas (2) or (3).

[0553]

[0554] In Equation (2), R q1 It is a hydrocarbyl group having 1 to 40 carbon atoms that may contain a hydrogen atom or a heteroatom, except that the hydrogen atom bonded to the carbon atom at the α-position of the sulfo group is substituted with a fluorine atom or a fluoroalkyl group. In Formula (3), R q2 It is a hydrocarbyl group having 1 to 40 carbon atoms that may include hydrogen atoms or heteroatoms.

[0555] R q1 A hydrocarbyl group having 1 to 40 carbon atoms represented by, specifically, an alkyl group having 1 to 40 carbon atoms such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, tert-pentyl group, n-hexyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group; a cyclopentyl group, cyclohexyl group, cyclopentylmethyl group, cyclopentylethyl group, cyclopentylbutyl group, cyclohexylmethyl group, cyclohexylethyl group, cyclohexylbutyl group, norbornyl group, tricyclo[5.2.1.0 2,6Examples include cyclic saturated hydrocarbyl groups having 3 to 40 carbon atoms, such as decyl groups and adamantyl groups; and aryl groups having 6 to 40 carbon atoms, such as phenyl groups, naphthyl groups, and anthracenyl groups. Additionally, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms, and as a result, may include hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, lactone rings, sulfone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0556] R q2 As a hydrocarbyl group represented by, specifically, R q1 In addition to the substituents exemplified as specific examples, fluorinated saturated hydrocarbyl groups such as trifluoromethyl groups and trifluoroethyl groups, or fluorinated aryl groups such as pentafluorophenyl groups and 4-trifluoromethylphenyl groups may also be cited.

[0557] Specific examples of the anion of the onium salt represented by formula (2) include those shown below, but are not limited to these.

[0558]

[0559]

[0560]

[0561]

[0562]

[0563] Specific examples of the anion of the onium salt represented by formula (3) include those shown below, but are not limited to these.

[0564]

[0565]

[0566]

[0567]

[0568]

[0569] Among equations (2) and (3), Mq + is an onium cation. Examples of the above onium cation include sulfonium cations, iodonium cations, ammonium cations, etc. Specific examples of the above sulfonium cation include those exemplified as specific examples of cations of sulfonium salts represented by formula (1), those described in paragraphs

[0102] to

[0125] of Japanese Patent Publication No. 2024-3744, those described in paragraphs

[0044] to

[0049] of International Publication No. 2024 / 128017, those described in paragraphs

[0035] to

[0046] of Patent Publication No. 7491173, and those exemplified as specific examples of sulfonium cations represented by formula (sulfo-1), but are not limited thereto. Specific examples of iodium cations include those described in paragraph

[0181] of Japanese Patent Publication No. 2024-259, but are not limited thereto. Specific examples of the ammonium cations include those exemplified as specific examples of ammonium cations represented by the formula (am-1).

[0570] Specific examples of the onium salts represented by formula (2) or (3) include any combination of the aforementioned anions and cations. Furthermore, these onium salts are easily prepared by an ion exchange reaction using known organic chemical methods. For ion exchange reactions, for example, Japanese Patent Publication No. 2007-145797 may be referenced.

[0571] The onium salt represented by formula (2) or (3) acts as a quencher in the chemical amplification resist composition of the present invention. This is because each counter anion of the onium salt is a conjugate base of a weak acid. The term "weak acid" here means an acidity that cannot deprotect the acid unstable group of the acid unstable group-containing unit used in the base polymer. The onium salt represented by formula (2) or (3) functions as a quencher when used in combination with an onium salt-type photogenerator having a conjugate base of a strong acid, such as a sulfonic acid with the α position fluorinated, as a counter anion. That is, when a mixture of an onium salt that generates a strong acid, such as a sulfonic acid with an α-position fluorinated, and an onium salt that generates a weak acid, such as a sulfonic acid or a carboxylic acid that is not fluorinated, is used, when the strong acid generated from the photogenerative agent by high-energy ray irradiation collides with the onium salt containing unreacted weak acid anions, the weak acid is released through salt exchange and an onium salt containing strong acid anions is generated. In this process, since the strong acid is exchanged for a weak acid with lower catalytic activity, the acid is seemingly deactivated, and acid diffusion can be controlled.

[0572] In addition, (D) as a quencher, an onium salt having a sulfonium cation and a phenoxide anion site within the same molecule as described in Japanese Patent Publication No. 6848776, an onium salt having a sulfonium cation and a carboxylate anion site within the same molecule as described in Japanese Patent Publication No. 6583136 and Japanese Patent Publication No. 2020-200311, and an onium salt having an iodonium cation and a carboxylate anion site within the same molecule as described in Japanese Patent Publication No. 6274755 may be used.

[0573] Here, when the photogenerative agent that generates a strong acid is an onium salt, as mentioned above, the strong acid generated by high-energy irradiation can be exchanged for a weak acid, but on the other hand, it is thought that the weak acid generated by high-energy irradiation cannot collide with the onium salt that generates an unreacted strong acid to perform salt exchange. This is due to the phenomenon that onium cations are more likely to form ion pairs with the anions of strong acids.

[0574] When the chemical amplification resist composition of the present invention includes an onium salt represented by formula (2) or (3) as (D) quencher, the content thereof is preferably 0.1 to 20 parts by mass and more preferably 0.1 to 10 parts by mass with respect to 80 parts by mass of the base polymer (B). It is desirable that the content of the onium salt type quencher be within the above range because the resolution is good and the sensitivity is not significantly reduced. The onium salt represented by formula (2) or (3) may be used as a single type or in combination of two or more types.

[0575] The chemical amplification resist composition of the present invention may include (D) a nitrogen-containing compound as a quencher. Specific examples of the nitrogen-containing compound include primary, secondary, or tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Publication No. 2008-111103, in particular amine compounds having a hydroxyl group, an ether bond, an ester bond, a lactone ring, a cyano group, or a sulfonic acid ester bond. Additionally, compounds in which a primary or secondary amine is protected by a carbamate group as described in Japanese Patent Publication No. 3790649 may also be included.

[0576] In addition, a sulfonium sulfonate salt having a nitrogen-containing substituent may be used as a nitrogen-containing compound. Such a compound functions as a so-called photodisintegrating base, which functions as a quencher in the unexposed area and loses its quenching ability in the exposed area through neutralization with its own generated acid. By using a photodisintegrating base, the contrast between the exposed area and the unexposed area can be further enhanced. As for photodisintegrating bases, reference may be made to, for example, Japanese Patent Publication No. 2009-109595 and Japanese Patent Publication No. 2012-46501.

[0577] When the chemical amplification resist composition of the present invention includes a nitrogen-containing compound as (D) a quencher, the content thereof is preferably 0.001 to 12 parts by mass and more preferably 0.01 to 8 parts by mass with respect to 80 parts by mass of (B) base polymer. The nitrogen-containing compound may be used alone or in combination of two or more types.

[0578] [(E) Other Mining Agents]

[0579] The chemical amplification resist composition of the present invention may include a photogenerative agent other than component (A) (hereinafter also referred to as an other photogenerative agent) as component (E). The other photogenerative agent is not particularly limited as long as it is a compound that generates a strong acid upon high-energy irradiation. Suitable other photogenerative agents may be those represented by the following formulas (4) or (5).

[0580]

[0581] Among equations (4) and (5), R 101 to R 105 is a hydrocarbyl group having 1 to 20 carbon atoms, which may each independently contain a halogen atom or a heteroatom. In addition, R 101 , R 102 and R 103Any two of them may combine with each other to form a ring together with the sulfur atom to which they combine. As a specific example of the above hydrocarbyl group, R in the explanation of Formula (1) 1 to R 3 Examples of hydrocarbilic groups indicated as such can be cited as those exemplified.

[0582] Specific examples of the sulfonium salt cation represented by Formula (4) include those exemplified as specific examples of the sulfonium salt cation represented by Formula (1), those described in paragraphs

[0102] to

[0125] of Japanese Patent Publication No. 2024-3744, those described in paragraphs

[0044] to

[0049] of International Publication No. 2024 / 128017, those described in paragraphs

[0035] to

[0046] of Patent No. 7491173, and those exemplified as specific examples of the sulfonium cation represented by Formula (Sulpho-1), but are not limited thereto. Specific examples of the iodonium salt cation represented by Formula (5) include those described in paragraph

[0181] of Japanese Patent Publication No. 2024-259, but are not limited thereto.

[0583] Among equations (4) and (5), Xa - is an anion of a strong acid. As the anion of the strong acid, the anion represented by formula (Z-1), the anion represented by formula (Z-2), the anion represented by formula (Z-3), the anion represented by formula (M-1), and the anion represented by formula (M-2) are preferred.

[0584] In addition, as an other light-generating agent of component (E), it is also desirable to have it represented by the following formula (6).

[0585]

[0586] In Equation (6), R 201 and R 202 R is a hydrocarbyl group having 1 to 30 carbon atoms, which may each independently contain a heteroatom. 203It is a hydrocarbylene group having 1 to 30 carbon atoms that may contain heteroatoms. Also, R 201 , R 202 and R 203 Any two of them may combine with each other to form a ring together with the sulfur atom to which they combine.

[0587] R 201 and R 202 The hydrocarbyl group having 1 to 30 carbon atoms represented by may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, tert-pentyl, n-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentyl methyl, cyclopentyl ethyl, cyclopentyl butyl, cyclohexyl methyl, cyclohexyl ethyl, cyclohexyl butyl, norbornyl, oxanorbornyl, tricyclo[5.2.1.0 2,6Examples include cyclic saturated hydrocarbyl groups having 3 to 30 carbon atoms, such as decyl groups and adamantyl groups; aryl groups having 6 to 30 carbon atoms, such as phenyl groups, methylphenyl groups, ethylphenyl groups, n-propylphenyl groups, isopropylphenyl groups, n-butylphenyl groups, isobutylphenyl groups, sec-butylphenyl groups, tert-butylphenyl groups, naphthyl groups, methylnaphthyl groups, ethylnaphthyl groups, n-propylnaphthyl groups, isopropylnaphthyl groups, n-butylnaphthyl groups, isobutylnaphthyl groups, sec-butylnaphthyl groups, tert-butylnaphthyl groups, and anthracenyl groups; and groups obtained by combining these. In addition, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen atoms, sulfur atoms, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0588] R 203The hydrocarbylene group having 1 to 30 carbon atoms, represented by, may be saturated or unsaturated, and may be straight, branched, or cyclic. Specific examples thereof include alkanedyl groups having 1 to 30 carbon atoms, such as methanediyl group, ethane-1,1-diyl group, ethane-1,2-diyl group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group; Examples include cyclic saturated hydrocarbylene groups having 3 to 30 carbon atoms, such as cyclopentanediyl, cyclohexanediyl, norbornandiyl, and adamantandiyl; and arylene groups, such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, and tert-butylnaphthylene. In addition, some or all of the hydrogen atoms of the hydrocarbylene group may be substituted with a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- of the hydrocarbylene group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, may include a hydroxyl group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sulfone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. As the heteroatom, an oxygen atom is preferred.

[0589] In formula (6), L21 It is a hydrocarbylene group having 1 to 20 carbon atoms that may include single bonds, ether bonds, or heteroatoms. The hydrocarbylene group may be saturated or unsaturated, and may be straight, branched, or cyclic. Specific examples thereof include R 203 Examples of hydrocarbylene groups represented as such can be given as those similar to the example.

[0590] In equation (6), X a , X b , X c and X d is, each independently, a hydrogen atom, a fluorine atom, or a trifluoromethyl group. provided that X a , X b , X c and X d At least one of them is a fluorine atom or a trifluoromethyl group.

[0591] As for the mine generator represented by formula (6), it is preferable to have it represented by the following formula (6').

[0592]

[0593] In equation (6'), L 21 Eun is identical to the above. X e It is silver, a hydrogen atom, or a trifluoromethyl group, preferably a trifluoromethyl group. R 301 , R 302 and R 303 It is a hydrocarbyl group having 1 to 20 carbon atoms, which may each independently contain a hydrogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be straight, branched, or cyclic. As a specific example, R in formula (Z-1-1). 11a Examples of hydrocarbyl groups represented by can be given as those exemplified. p and q are each independently 0, 1, 2, 3, 4 or 5, and r is 0, 1, 2, 3 or 4.

[0594] Specific examples of the light-generating agent represented by formula (6) include those similar to the light-generating agent represented by formula (2) in Japanese Patent Publication No. 2017-26980.

[0595] Among the above other photocatalytic agents, those containing anion represented by formula (Z-1-1) or (Z-4) have low acid diffusion and excellent solubility in solvents, which is particularly desirable. Additionally, those represented by formula (6') have very low acid diffusion, which is particularly desirable.

[0596] When the chemical amplification resist composition of the present invention includes (E) other photogenerators, the content thereof is preferably 0.1 to 40 parts by mass and more preferably 0.5 to 20 parts by mass with respect to 80 parts by mass of (B) base polymer. It is desirable that the amount of photogenerator added in component (E) be within the above range, as this results in good resolution and eliminates the risk of foreign matter issues occurring after development or peeling of the resist film. (E) other photogenerators may be used as a single type or in combination of two or more types.

[0597] [(F) Surfactant]

[0598] The chemical amplification resist composition of the present invention may additionally include a surfactant as component (F). Preferably, (F) the surfactant is a surfactant that is insoluble or sparingly soluble in water and soluble in an alkaline developer, or a surfactant that is insoluble or sparingly soluble in water and an alkaline developer. As such a surfactant, reference may be made to those described in Japanese Patent Publication No. 2010-215608 or Japanese Patent Publication No. 2011-16746.

[0599] Among the surfactants described in the above publication, FC-4430 (manufactured by 3M), Surflon (registered trademark) S-381 (manufactured by AGC Seimi Chemical Co., Ltd.), Olfin (registered trademark) E1004 (manufactured by Nissin Kagaku Kogyo Co., Ltd.), KH-20, KH-30 (manufactured by AGC Seimi Chemical Co., Ltd.), and oxetane ring-opening polymers represented by the following formula (surf-1) are preferred.

[0600]

[0601] Here, R, Rf, A, B, C, m, and n apply only to formula (surf-1), regardless of the description above. R is a 2 to 4-valent aliphatic group having 2 to 5 carbon atoms. Examples of the aliphatic groups include, for divalent groups, ethylene groups, 1,4-butylene groups, 1,2-propylene groups, 2,2-dimethyl-1,3-propylene groups, 1,5-pentylene groups, etc., and for trivalent or 4-valent groups, the following may be examples.

[0602]

[0603] (In the formulas, dashed lines are bonding hands and are substructures derived from glycerol, trimethylolethane, trimethylolpropane, and pentaerythritol, respectively.)

[0604] Among these, 1,4-butylene groups, 2,2-dimethyl-1,3-propylene groups, etc. are preferred.

[0605] Rf is a trifluoromethyl group or a pentafluoroethyl group, preferably a trifluoromethyl group. m is an integer from 0 to 3, n is an integer from 1 to 4, the sum of n and m is the valence of R, and is an integer from 2 to 4. A is 1. B is an integer from 2 to 25, preferably an integer from 4 to 20. C is an integer from 0 to 10, preferably 0 or 1. In addition, the arrangement of each constituent unit in formula (surf-1) is not specified, and they may be joined blockwise or randomly. Details regarding the preparation of a partially fluorinated oxetane ring-opening polymer-based surfactant are provided in U.S. Patent No. 5650483, etc.

[0606] Surfactants that are insoluble or sparingly soluble in water and soluble in alkaline developers have the function of reducing water penetration or leaching by orienting them on the surface of the resist film when a resist protective film is not used in ArF immersion lithography. Therefore, they are useful for suppressing the leaching of water-soluble components from the resist film to reduce damage to the exposure device, and are also useful because they become soluble during alkaline aqueous development after exposure or post-exposure baking (PEB) and are unlikely to become foreign substances that cause defects. Such surfactants are polymeric surfactants with the property of being insoluble or sparingly soluble in water and soluble in alkaline developers, and are also called hydrophobic resins; it is particularly desirable to improve water activity by having high water repellency.

[0607] Specific examples of such polymeric surfactants include at least one selected from the repeating unit represented by the following formula (7A) (hereinafter also referred to as repeating unit 7A), the repeating unit represented by the following formula (7B) (hereinafter also referred to as repeating unit 7B), the repeating unit represented by the following formula (7C) (hereinafter also referred to as repeating unit 7C), the repeating unit represented by the following formula (7D) (hereinafter also referred to as repeating unit 7D), and the repeating unit represented by (7E) (hereinafter also referred to as repeating unit 7E).

[0608]

[0609] Among formulas (7A) to (7E), R B is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. W 1 It is -CH2-, -CH2CH2-, -O-, or two separate -Hs. R s1 Each is independently a hydrogen atom or a hydrocarbyl group having 1 to 10 carbon atoms. R s2 is a single bond, or a straight-chain or branched hydrocarbylene group having 1 to 5 carbon atoms. R s3 Each is independently a hydrogen atom, a hydrocarbyl group having 1 to 15 carbon atoms or a fluorinated hydrocarbyl group, or an acid instability group. R s3 In the case of this hydrocarbyl group or fluorinated hydrocarbyl group, an ether bond or a carbonyl group may be interposed between the carbon-carbon bonds. R s4 is a (u+1) valence hydrocarbon group or a fluorinated hydrocarbon group having 1 to 20 carbon atoms. u is 1, 2, or 3. R s5 are, respectively, hydrogen atoms, or -C(=O)-OR sa It is a unit represented by . R sa is a fluorinated hydrocarbyl group having 1 to 20 carbon atoms. R s6The carbon atom is a hydrocarbyl group having 1 to 15 carbon atoms or a fluorinated hydrocarbyl group, and an ether bond or a carbonyl group may be interposed between the carbon-carbon bonds.

[0610] R s1 The hydrocarbyl group having 1 to 10 carbon atoms represented by is preferably a saturated hydrocarbyl group and may be straight, branched, or cyclic. Specific examples include alkyl groups having 1 to 10 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; and cyclic saturated hydrocarbyl groups having 3 to 10 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, and norbornyl groups. Among these, those having 1 to 6 carbon atoms are preferred.

[0611] R s2 The hydrocarbylene group represented by is preferably a saturated hydrocarbylene group and may be straight, branched, or cyclic. Specific examples include methylene groups, ethylene groups, propylene groups, butylene groups, pentylene groups, etc.

[0612] R s3 or R s6 The hydrocarbyl group represented by may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include saturated hydrocarbyl groups, aliphatic unsaturated hydrocarbyl groups such as alkenyl groups and alkynyl groups, but saturated hydrocarbyl groups are preferred. Specific examples of the above-mentioned saturated hydrocarbyl group include R s1 In addition to the hydrocarbyl group represented by , examples include undecyl, dodecyl, tridecyl, tetradecyl, and pentadecyl groups. R s3 or R s6As a fluorinated hydrocarbyl group represented by, examples include a group in which some or all of the hydrogen atoms bonded to the carbon atoms of the aforementioned hydrocarbyl group are substituted with fluorine atoms. As previously mentioned, an ether bond or a carbonyl group may be interposed between these carbon-carbon bonds.

[0613] R s3 Specific examples of acid instability groups represented by the above-described formulas (AL-3) to (AL-5) include trialkylsilyl groups in which each alkyl group has 1 to 6 carbon atoms, and oxo-containing alkyl groups having 4 to 20 carbon atoms.

[0614] R s4 The (u+1) valence hydrocarbon group or fluorinated hydrocarbon group represented by can be straight-chain, branched, or cyclic, and specific examples thereof include a group obtained by removing u more hydrogen atoms from the aforementioned hydrocarbyl group or fluorinated hydrocarbyl group.

[0615] R sa The fluorinated hydrocarbyl group represented by is preferably saturated and may be straight, branched, or cyclic. Specific examples thereof include cases where some or all of the hydrogen atoms of the hydrocarbyl group are substituted with fluorine atoms, and specific examples thereof include a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoro-1-propyl group, a 3,3,3-trifluoro-2-propyl group, a 2,2,3,3-tetrafluoropropyl group, a 1,1,1,3,3,3-hexafluoroisopropyl group, a 2,2,3,3,4,4,4-heptafluorobutyl group, a 2,2,3,3,4,4,5,5-octafluoropentyl group, a 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl group, a 2-(perfluorobutyl)ethyl group, a 2-(perfluorohexyl)ethyl group, a 2-(perfluorooctyl)ethyl group, Examples include 2-(perfluorodecyl)ethyl groups.

[0616] Specific examples of repeating units 7A to 7E may be those shown below, but are not limited thereto. In addition, among the following formulas, R B is the same as above.

[0617]

[0618]

[0619]

[0620]

[0621]

[0622]

[0623] The above polymeric surfactant may additionally include other repeating units other than repeating units 7A to 7E. Specific examples of other repeating units include repeating units obtained from methacrylic acid or α-trifluoromethylacrylic acid derivatives. Among the polymeric surfactant, the content of repeating units 7A to 7E is preferably 20 mol% or more of the total repeating units, more preferably 60 mol% or more, and even more preferably 100 mol%.

[0624] The Mw of the above polymeric surfactant is preferably 1,000 to 500,000, and more preferably 3,000 to 100,000. The Mw / Mn is preferably 1.0 to 2.0, and more preferably 1.0 to 1.6.

[0625] As a method for synthesizing the above polymeric surfactant, a monomer comprising an unsaturated bond that provides at least one repeating unit selected from 7A to 7E and, if necessary, other repeating units is heated in an organic solvent with the addition of a radical initiator and polymerized. Specific examples of organic solvents used during polymerization include toluene, benzene, THF, diethyl ether, dioxane, etc. Specific examples of polymerization initiators include AIBN, 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2-azobis(2-methylpropionate), benzoyl peroxide, lauroyl peroxide, etc. The reaction temperature is preferably 50 to 100°C. The reaction time is preferably 4 to 24 hours. The acid instability group may be used as is introduced into the monomer, or may be protected or partially protected after polymerization.

[0626] When synthesizing the above polymeric surfactant, known chain transfer agents such as dodecyl mercaptan or 2-mercaptoethanol may be used to adjust the molecular weight. In that case, the amount of these chain transfer agents added is preferably 0.01 to 10 mol% with respect to the total moles of the monomers to be polymerized.

[0627] When the chemical amplification resist composition of the present invention includes (F) a surfactant, the content thereof is preferably 0.1 to 50 parts by mass and more preferably 0.5 to 10 parts by mass with respect to 80 parts by mass of (B) base polymer. If the content of (F) surfactant is 0.1 parts by mass or more, the receding contact angle between the surface of the resist film and water is sufficiently improved, and if it is 50 parts by mass or less, the dissolution rate of the surface of the resist film with respect to the developer is low, so the height of the formed fine pattern is sufficiently maintained. (F) surfactant may be used as a single type or as a combination of two or more types.

[0628] [(G) Other ingredients]

[0629] The chemical amplification resist composition of the present invention may include (G) other components, a compound that decomposes by acid and generates acid (acid-producing compound), an organic acid derivative, a fluorine-substituted alcohol, a compound having an Mw of 3000 or less that changes solubility in a developer solution by the action of acid (dissolution inhibitor), etc. As for the acid-producing compound, reference may be made to the compounds described in Japanese Patent Publication No. 2009-269953 or Japanese Patent Publication No. 2010-215608. When the acid-producing compound is included, the content thereof is preferably 0 to 5 parts by mass and more preferably 0 to 3 parts by mass with respect to (B) 80 parts by mass of the base polymer. If the content is too high, it becomes difficult to control acid diffusion, and deterioration of resolution and pattern shape may occur. As for the above organic acid derivative, fluorine-substituted alcohol, and solubility inhibitor, reference may be made to the compounds described in Japanese Patent Publication No. 2009-269953 or Japanese Patent Publication No. 2010-215608.

[0630] [Pattern Formation Method]

[0631] The pattern forming method of the present invention comprises a process of forming a resist film on a substrate using the aforementioned chemical amplification resist composition, a process of exposing the resist film to high-energy rays, and a process of developing the exposed resist film using a developer.

[0632] As the above substrate, for example, a substrate for manufacturing integrated circuits (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflective film, etc.) or a substrate for manufacturing mask circuits (Cr, CrO, CrON, MoSi2, SiO2, etc.) may be used.

[0633] A resist film can be formed by applying the chemical amplification resist composition onto a substrate such that the film thickness is preferably 0.05 to 2 μm by a method such as spin coating, for example, and pre-baking it on a hot plate, preferably at 60 to 150°C for 1 to 10 minutes, more preferably at 80 to 140°C for 1 to 5 minutes.

[0634] Examples of high-energy rays used for exposing the resist film include KrF excimer laser light, ArF excimer laser light, EB, and EUV with a wavelength of 3 to 15 nm. When using KrF excimer laser light, ArF excimer laser light, or EUV, exposure can be performed by using a mask to form a target pattern and irradiating with an exposure amount preferably 1 to 200 mJ / cm², more preferably 10 to 100 mJ / cm². When using EB, exposure can be performed by using a mask to form a target pattern or directly, with an exposure amount preferably 1 to 300 μC / cm², more preferably 10 to 200 μC / cm².

[0635] In addition, in addition to the conventional exposure method, it is also possible to use an immersion method in which a liquid with a refractive index of 1.0 or higher is interposed between the resist film and the projection lens. In that case, it is also possible to use a protective film that is insoluble in water.

[0636] The above-mentioned water-insoluble protective film is used to prevent leaching from the resist film and to increase the water-repellent properties of the film surface, and is broadly classified into two types. One is an organic solvent stripping type that requires stripping before alkaline aqueous solution development by an organic solvent that does not dissolve the resist film, and the other is an alkaline aqueous solution soluble type that is soluble in the alkaline developer and removes the protective film along with the removal of the resist film-soluble portion. The latter is particularly preferred as a material based on a polymer having 1,1,1,3,3,3-hexafluoro-2-propanol residues that are insoluble in water and soluble in the alkaline developer, dissolved in an alcohol-based solvent having 4 or more carbon atoms, an ether-based solvent having 8 to 12 carbon atoms, or a mixture of these solvents. The aforementioned water-insoluble and alkaline developer-soluble surfactant may also be a material dissolved in an alcohol-based solvent having 4 or more carbon atoms, an ether-based solvent having 8 to 12 carbon atoms, or a mixture of these solvents.

[0637] After exposure, PEB may be performed. PEB can be performed, for example, by heating on a hot plate at 60 to 150°C for 1 to 5 minutes, more preferably at 80 to 140°C for 1 to 3 minutes.

[0638] The development is performed by using a developer solution of an alkaline aqueous solution, such as tetramethylammonium hydroxide (TMAH), preferably 0.1 to 5 mass%, more preferably 2 to 3 mass%, preferably for 0.1 to 3 minutes, more preferably for 0.5 to 2 minutes, by conventional methods such as the dip method, puddle method, and spray method, so that the exposed portion is dissolved and a desired pattern is formed on the substrate.

[0639] In addition, after forming the resist film, extraction of acid-generating agents from the film surface or washing away of particles may be performed by rinsing with water, or a rinse may be performed to remove water remaining on the film after exposure.

[0640] In addition, a pattern may be formed by a double patterning method. Examples of double patterning methods include a trench method in which a 1:3 trench pattern substrate is processed by a first exposure and etching, and a 1:3 trench pattern is formed by a second exposure with offset to form a 1:1 pattern, and a line method in which a first substrate of a 1:3 isolated residual pattern is processed by a first exposure and etching, and a second substrate formed by a second exposure with offset to form a 1:3 isolated residual pattern under the first substrate to form a 1:1 pattern with half the pitch.

[0641] In the pattern forming method of the present invention, instead of the alkaline aqueous solution as the developer, an organic solvent may be used to dissolve the unexposed area, and a negative tone development method may be used.

[0642] In the above organic solvent development, as a developer, 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutylketone, methylcyclohexanone, acetophenone, methylacetophenone, propyl acetate, butyl acetate, isobutyl acetate, pentyl acetate, butenyl acetate, isopentyl acetate, propyl formate, butyl formate, isobutyl formate, pentyl formate, isopentyl formate, methyl valerate, methyl penthenate, methyl crotonicate, ethyl crotonicate, methyl propionate, ethyl propionate, 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, Pentyl lactate, isopentyl lactate, 2-methyl isobutyrate, 2-ethyl hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, ethyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, 2-phenylethyl acetate, etc., may be used. These organic solvents may be used individually or in a mixture of two or more types.

[0643] Examples

[0644] The present invention will be specifically described below by presenting synthesis examples, examples, and comparative examples, but the present invention is not limited to the following examples. In addition, the apparatus used is as follows.

[0645] ·MALDI TOF-MS: Nihon Denshi Co., Ltd. S3000

[0646] [1] Synthesis of sulfonium salts

[0647] [Example 1-1] Synthesis of Sulfonium Salt PAG-1

[0648]

[0649] (1) Synthesis of PAG-1

[0650] Under a nitrogen atmosphere, raw material In-1 (8.6g), raw material SM-2 (4.9g), methylene chloride (50g), and water (30g) were added and stirred for 15 minutes, after which the organic layer was taken off and washed with water, and then concentrated under reduced pressure. Methyl isobutyl ketone (50g) was added to the concentrate to perform azeotropic dehydration, and the residue was purified by silica gel column chromatography to obtain 10.9g of the target product PAG-1 as an oil phase (yield 94%).

[0651] MALDI TOF-MS: POSITIVE M + 447(C 20 H 16 F5O2S2 + (Significant)

[0652] NEGATIVE M - 711(C 10 H3F5I3O5S - (Significant)

[0653] [Examples 1-2 to 1-9] Synthesis of Sulfonium Salts PAG-2 to PAG-9

[0654] Sulfonium salts PAG-2 to PAG-9 represented by the following formulas were synthesized using corresponding raw materials and known organic synthesis reactions.

[0655]

[0656]

[0657]

[0658] [2] Synthesis of base polymer

[0659] [Synthesizing Example] Synthesis of base polymers (P-1 to P-5)

[0660] Each monomer was combined and copolymerized in MEK, a solvent; the reaction solution was added to hexane; the precipitated solid was washed with hexane, isolated, and dried to obtain base polymers (P-1 to P-5) having the compositions shown below. The composition of the obtained base polymers is 1 Mw and Mw / Mn were confirmed by H-NMR and GPC (solvent: THF, standard: polystyrene).

[0661]

[0662] [3] Preparation of a chemical amplification resist composition

[0663] [Examples 2-1 to 2-30, Comparative Examples 1-1 to 1-20]

[0664] Chemical amplification resist compositions (R-1 to R-30 and CR-1 to CR-20) were prepared by dissolving the photogenerators (PAG-1 to PAG-9) containing the sulfonium salt of the present invention, comparative photogenerators (PAG-A to PAG-E), other photogenerators (PAG-X), base polymers (P-1 to P-5), and quenchers (Q-1 to Q-4) in a solvent containing 0.01 mass% of surfactant A (Omnovasa) in the compositions shown in Tables 1 and 2 below, and by filtering the said solution with a 0.2 μm Teflon (registered trademark) type filter.

[0665]

[0666]

[0667] Among Tables 1 and 2, the solvent, other photocatalytic agents PAG-X, PAG-Y, comparative photocatalytic agents PAG-A to PAG-E, quenchers Q-1 to Q-4, and surfactant A are as follows.

[0668] · Solvent: PGMEA (propylene glycol monomethyl ether acetate)

[0669] DAA (diacetone alcohol)

[0670] · Other mine generators: PAG-X

[0671]

[0672] · Comparative photogeneratives: PAG-A to PAG-E

[0673]

[0674] ·Quencher: Q-1 to Q-4

[0675]

[0676] · Surfactant A: 3-methyl-3-(2,2,2-trifluoroethoxymethyl)oxetane·tetrahydrofuran·2,2-dimethyl-1,3-propanediol copolymer (Omnovasage)

[0677]

[0678] a: (b+b'):(c+c')=1:4 to 7:0.01 to 1 (molar ratio)

[0679] Mw=1500

[0680] [4] EUV lithography evaluation (1)

[0681] [Examples 3-1 to 3-30, Comparative Examples 2-1 to 2-20]

[0682] Each chemical amplification resist composition (R-1 to R-30, CR-1 to CR-20) shown in Tables 1 to 3 was spin-coated onto a Si substrate formed with a silicon-containing spin-on hard mask SHB-A940 (silicon content of 43 mass%) manufactured by Shin-Etsu Chemical Co., Ltd. to a film thickness of 20 nm, and pre-baked at 100°C for 60 seconds using a hot plate to produce a resist film with a film thickness of 50 nm. With respect to the above resist film, an LS pattern with wafer dimensions of 18 nm and a pitch of 36 nm was exposed using an ASML EUV scanner NXE3400 (NA 0.33, σ 0.9 / 0.6, dipole illumination) while varying the exposure amount and focus (exposure amount pitch: 1 mJ / cm², focus pitch: 0.020 μm), and after exposure, PEB was performed for 60 seconds at the temperatures shown in Tables 4 and 5. Subsequently, puddle development was performed for 30 seconds with a 2.38 mass% aqueous TMAH solution, rinsed with a surfactant-containing rinse material, and spin-dried to obtain a positive pattern.

[0683] The obtained LS pattern was observed using a Hitachi High-Tech Corporation measuring SEM (CG6300), and sensitivity, EL, LWR, depth of focus (DOF), and collapse limit were evaluated according to the following methods. In addition, the developed defects of the obtained LS pattern were evaluated. The results are shown in Tables 3 and 4.

[0684] [Sensitivity Evaluation]

[0685] The optimal exposure dose Eop (mJ / cm²) for obtaining an LS pattern with a line width of 18 nm and a pitch of 36 nm was determined and used as the sensitivity. The smaller this value, the higher the sensitivity.

[0686] [EL Evaluation]

[0687] EL (unit: %) was calculated from the exposure amount formed within the range of ±10% (16.2 to 19.8 nm) of the 18 nm space width in the above LS pattern using the following formula. The larger this value, the better the performance.

[0688] EL(%)=(|E1-E2| / Eop)×100

[0689] E1: Optimal exposure amount for imparting an LS pattern with a line width of 16.2 nm and a pitch of 36 nm

[0690] E2: Optimal exposure amount for imparting an LS pattern with a line width of 19.8 nm and a pitch of 36 nm

[0691] Eop: Optimal exposure amount for imparting an LS pattern with a line width of 18 nm and a pitch of 36 nm

[0692] [LWR Evaluation]

[0693] The LS pattern obtained by investigating with Eop was measured at 10 points along the length of the line, and the value of three times the standard deviation (σ) (3σ) from the result was calculated as LWR. The smaller this value, the smaller the roughness and the more uniform the line width pattern is obtained.

[0694] [DOF Evaluation]

[0695] As an evaluation of the depth of focus, a focus range formed within ±10% (16.2 to 19.8 nm) of the 18 nm dimension in the above LS pattern was determined. The larger this value, the wider the depth of focus.

[0696] [Assessment of Line Pattern Breakdown Limit]

[0697] The line dimensions of each exposure amount at the optimal focus of the above LS pattern were measured at 10 points along the length. The thinnest line dimension obtained without collapse was set as the collapse limit dimension. The smaller this value, the better the collapse limit.

[0698] [Survey of Phenomenon Defects]

[0699] An LS pattern with a line width of 18 nm and a pitch of 36 nm formed with the above optimal exposure amount was used with a defect inspection device KLA2360 (product name) manufactured by K.L.A. Tenkors. The pixel size of the defect inspection device was set to 0.16 μm and the threshold to 20. Defects (number / cm²) extracted from the difference caused by pixel-level overlap with a comparison image were detected, and the number of defects per unit area (number / cm²) was calculated. Subsequently, developed defects were classified and extracted from the total defects by performing a defect review, and the number of developed defects per unit area (number / cm²) was calculated. Values ​​less than 0.5 were designated as A, values ​​0.5 or more but less than 1.0 as B, values ​​1.0 or more but less than 5.0 as C, and values ​​5.0 or more as D. A smaller value indicates better performance.

[0700]

[0701]

[0702] From the results shown in Tables 3 and 4, it can be seen that the chemical amplification resist composition containing a photogenerative agent containing a sulfonium salt of the present invention exhibits good sensitivity and excellent EL, LWR, and DOF. Furthermore, it was confirmed that the breakdown limit value is small, indicating resistance to pattern breakdown even during fine pattern formation. Additionally, it was confirmed that development defects are suppressed. Therefore, the chemical amplification resist composition of the present invention is suitable as a material for EUV lithography.

[0703] [5] EUV lithography evaluation (2)

[0704] [Examples 4-1 to 4-30, Comparative Examples 3-1 to 3-20]

[0705] Each chemical amplification resist composition (R-1 to R-30, CR-1 to CR-20) shown in Tables 1 to 3 was spin-coated onto a Si substrate formed with a silicon-containing spin-on hard mask SHB-A940 (silicon content of 43 mass%) manufactured by Shin-Etsu Chemical Co., Ltd. to a film thickness of 20 nm, and pre-baked at 105°C for 60 seconds using a hot plate to produce a resist film with a film thickness of 50 nm. The above resist film was exposed using an ASML EUV scanner NXE3400 (NA0.33, σ 0.9 / 0.6, quadruple illumination, wafer dimensions, pitch 46 nm, mask of a hole pattern with +20% bias), and PEB was performed for 60 seconds at the temperature specified in Tables 5 and 6 using a hot plate, and development was performed for 30 seconds with a 2.38 mass% TMAH aqueous solution to form a hole pattern with dimensions of 23 nm.

[0706] Using a measuring SEM (CG6300) manufactured by Hitachi High-Tech Corp., the exposure amount at which the hole dimensions are formed to 23 nm was measured and this was set as the sensitivity. Additionally, the dimensions of 50 holes at this time were measured, and the value of three times the standard deviation (σ) calculated from the result (3σ) was set as the CDU. The results are shown in Tables 5 and 6.

[0707]

[0708]

[0709] From the results shown in Tables 5 and 6, it was confirmed that the chemical amplification resist composition containing the photogenerative agent containing the sulfonium salt of the present invention has good sensitivity and excellent CDU.

Claims

Claim 1 Sulfonium salt represented by the following formula (1). (In the equation, n1 is 0 or 1. n2 is 0, 1 or 2. n3 is 0, 1 or 2. n4 is 0, 1 or 2. Provided that when n1 is 0, 0 ≤ n2 + n3 + n4 ≤ 5, and when n1 is 1, 0 ≤ n2 + n3 + n4 ≤ 7. n5 is 0 or 1. n6 is 0, 1 or 2. n7 is 0, 1 or 2. n8 is 0, 1 or 2. Provided that when n5 is 0, 0 ≤ n6 + n7 + n8 ≤ 5, and when n5 is 1, 0 ≤ n6 + n7 + n8 ≤ 7. n9 is 0 or 1. n10 is 0, 1 or 2. n11 is 0, 1 or 2. n12 is 0, 1 or 2. However, when n9 is 0, 0 ≤ n10 + n11 + n12 ≤ 5, and when n9 is 1, 0 ≤ n10 + n11 + n12 ≤ 7. Also, 1 ≤ n2 + n6 + n10 ≤ 6, and 1 ≤ n3 + n7 + n11 ≤ 6.R 1 , R 2 and R 3 It is a hydrocarbyl group having 1 to 20 carbon atoms, each of which may independently contain a heteroatom. When n3 is 2, each R 1 They may be identical or different. When n7 is 2, each R 2 They may be identical or different. When n11 is 2, each R 3 They may be identical or different. 4 , R 5 and R 6 Each is independently a halogen atom, a nitro group, a hydroxyl group, a carboxyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom. When n4 is 2, each R 4 They may be identical or different from each other, and 2 R 4 They may bond with each other to form a ring together with the carbon atom they bond to. When n8 is 2, each R 5 They may be identical or different from each other, and 2 R 5 They may bond with each other to form a ring together with the carbon atom they bond to. When n12 is 2, each R 6 They may be identical or different from each other, and 2 Rs 6 These may bond with each other to form a ring together with the carbon atoms they bond to. Also, S + Two of the three aromatic rings bonded to may bond with each other to form a ring together with the sulfur atom to which they bond. - is a fluoroalkanesulfonate anion that does not possess a polymerizable group. Claim 2 In paragraph 1, a sulfonium salt represented by the following formula (1A). (among the food, n2 to n4, n6 to n8, n10 to n12, R 1 to R 6 and Z - is the same as above.) Claim 3 In paragraph 1, Z - a. A sulfonium salt, which is an anion represented by any one of the following formulas (Z-1) to (Z-3). (during food, R 11 It is a hydrocarbyl group having 1 to 60 carbon atoms that may contain fluorine atoms or heteroatoms. 12 is a hydrocarbyl group having 1 to 40 carbon atoms that may contain heteroatoms. x is 1, 2, or 3. y is 1, 2, 3, 4, or 5. z is 0, 1, 2, or 3, provided that 1 ≤ y + z ≤ 5. X BI is an iodine atom or a bromine atom. 1 is a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a carbamate bond, or a saturated hydrocarbylene group having 1 to 6 carbon atoms, and a portion of the -CH2- of the said hydrocarbylene group may be substituted by an ether bond or an ester bond. 2 When x is 1, it is a hydrocarbylene group having 1 to 20 carbon atoms that may contain single bonds or heteroatoms, and when x is 2 or 3, it is a (x+1) hydrocarbon group having 1 to 20 carbon atoms that may contain heteroatoms. 3 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, carbonate bond, or carbamate bond. 13 hydroxyl group, carboxyl group, fluorine atom, chlorine atom, bromine atom, pentafluorosulfanyl group, amino group, hydrocarbyl group having 1 to 20 carbon atoms, hydrocarbyloxy group having 1 to 20 carbon atoms, hydrocarbylthio group having 1 to 20 carbon atoms, hydrocarbylcarbonyl group having 2 to 20 carbon atoms, hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms, hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms, hydrocarbylsulfonyloxy group having 1 to 20 carbon atoms, -N(R 13A )(R 13B ), -N(R 13C )-C(=O)-R 13D or -N(R 13C )-C(=O)-OR 13D And, the corresponding hydrocarbyl group, hydrocarbyloxy group, hydrocarbylthio group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may include at least one selected from a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a hydroxyl group, an amino group, an ester bond, and an ether bond. R 13A and R 13B is, each independently, a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. R 13C is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may include a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. 13D is an aliphatic hydrocarbyl group having 1 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may include a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. 1 to Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They may combine to form a carbonyl group.) Claim 4 A photocatalyst comprising a sulfonium salt as described in any one of paragraphs 1 to 3. Claim 5 A chemical amplification resist composition comprising a photogenerative agent as described in paragraph 4. Claim 6 A chemical amplification resist composition according to claim 5, further comprising a base polymer comprising at least one selected from a repeating unit represented by the following formula (a1), a repeating unit represented by the following formula (a2), and a repeating unit represented by the following formula (a3). (during food, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 It consists of single bonds, phenylene groups, naphthylene groups, or *-C(=O)-OX 11 - and, the corresponding phenylene group or naphthylene group may be substituted with a hydroxyl group, a nitro group, a cyano group, a saturated hydrocarbyl group having 1 to 10 carbon atoms that may include a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms that may include a fluorine atom, or a halogen atom. X 11 is a saturated hydrocarbylene group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may include a hydroxyl group, an ether bond, an ester bond, or a lactone ring. 2 is a single bond or *-C(=O)-O-*. * indicates a bond loss with a carbon atom in the main chain.R 21 It is a halogen atom, a cyano group, a hydroxyl group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom. When a1 is 2, 3, or 4, each R 21 They may be identical or different.AL 1 and AL 2 are each independently mountain instability groups. a1 is 0, 1, 2, 3, or 4.) (In the expression, b1 is 0 or 1. b2 is 0, 1, 2 or 3 when b1 is 0, and 0, 1, 2, 3, 4 or 5 when b1 is 1.R A is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 3 is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-. * indicates a bond loss with a carbon atom in the main chain. 4 is a single bond, an aliphatic hydrocarbylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a group obtained by a combination thereof. 5 and X 6 Each is independently an oxygen atom or a sulfur atom. However, X 4 and X 6 The aromatic ring is bonded to an adjacent carbon atom. 22 and R 23 It is a hydrocarbyl group having 1 to 20 carbon atoms, which may each independently contain a hydrogen atom or a heteroatom. Also, R 22 and R 23 These may combine with each other to form a ring together with the carbon atoms they bond to. 24 is a halogen atom, a hydroxyl group, a cyano group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylthio group having 1 to 20 carbon atoms that may contain a heteroatom, or -N(R 24A )(R 24B ) is. R 24A and R 24B Each is independently a hydrogen atom or a hydrocarbyl group having 1 to 6 carbon atoms. When b2 is 2 or more, each R 24 may be identical or different from each other, and multiple R 24 They may bond with each other to form a ring together with the carbon atoms of the aromatic ring to which they bond. Claim 7 A chemical amplification resist composition according to claim 6, wherein the polymer comprises repeating units represented by the following formula (b1) or (b2). (during food, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 is a single bond or *-C(=O)-O-. * indicates a bond loss with a carbon atom in the main chain.R 31 It is a group having 1 to 20 carbon atoms comprising at least one structure selected from hydrogen atoms, or hydroxyl groups other than phenolic hydroxyl groups, cyano groups, carbonyl groups, carboxyl groups, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, lactone rings, sulfone rings, and carboxylic acid anhydrides (-C(=O)-OC(=O)-). 32 is a halogen atom, a carboxyl group, a nitro group, a cyano group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom, a hydrocarbylcarbonyloxy group having 2 to 20 carbon atoms that may contain a heteroatom, or a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms that may contain a heteroatom. When c2 is 2, 3, or 4, each R 32 c1 and c2 may be identical or different. c1 is 1, 2, 3, or 4. c2 is 0, 1, 2, 3, or 4. Provided that 1 ≤ c1 + c2 ≤ 5. Claim 8 A chemical amplification resist composition according to claim 6, wherein the polymer comprises at least one selected from a repeating unit represented by the following formula (c1), a repeating unit represented by the following formula (c2), a repeating unit represented by the following formula (c3), a repeating unit represented by the following formula (c4), and a repeating unit represented by the following formula (c5). (In the equation, d1 and d2 are each independently 0, 1, 2, or 3. e1 is 0 or 1. e2 is 0, 1, 2, 3, or 4. e3 is 0, 1, 2, 3, or 4. Provided that when e1 is 0, 0 ≤ e2 + e3 ≤ 4, and when e1 is 1, 0 ≤ e2 + e3 ≤ 6.R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 It is a phenylene group that may have a single bond or a substituent. 2 is a single bond, **-C(=O)-OZ 21 -, **-C(=O)-N(H)-Z 21 - or **-OZ 21 -is. Z 21 It is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by a combination thereof, and may include a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. 3 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. 4 is a single bond, or a divalent group obtained by combining an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, or a combination thereof, and may include a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. 5 are, respectively, a single bond, a phenylene group that may have a substituent, a naphthylene group that may have a substituent, and *-C(=O)-OZ 51 - or *-C(=O)-N(R)-Z 51 -is. Z 51 is an aliphatic hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the aliphatic hydrocarbylene group may include a halogen atom, a hydroxyl group, an ether bond, an ester bond, or a lactone ring. R is a hydrocarbylene group having 1 to 10 carbon atoms that may include a hydrogen atom or a heteroatom. Z 6 It is a single bond, ether bond, ester bond, sulfonic acid ester bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. 7 Silver, each independently single bond, ***-Z 71 -C(=O)-O-, ***-C(=O)-N(R)-Z 71 - or ***-OZ 71 -is. Z 71 It is a hydrocarbylene group having 1 to 20 carbon atoms that may contain heteroatoms. R is the same as above. Z 8 Silver, each independently single bond, ****-Z 81 -C(=O)-O-, ****-C(=O)-N(R)-Z 81 - or ****-OZ 81 -is. Z 81 It is a hydrocarbylene group having 1 to 20 carbon atoms that may contain heteroatoms. R is the same as above. Z 9 is a single bond, methylene group, ethylene group, phenylene group, fluorinated phenylene group, phenylene group substituted with a trifluoromethyl group, *-C(=O)-OZ 91 -, *-C(=O)-N(R)-Z 91 - or *-OZ 91 -is. Z 91 is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a phenylene group substituted with a trifluoromethyl group, and may include a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. R is the same as above. * indicates a bond loss with a carbon atom of the main chain. ** is Z 1 Indicates the bonding loss with. *** is Z 6 Indicates the bond with. **** is Z 7 Represents the bonding loss with.L 11 It is a single bond, ether bond, ester bond, carbonyl group, sulfonic acid ester bond, sulfonamide bond, carbonate bond, or carbamate bond. Rf 11 and Rf 12 Each is independently a fluorine atom or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. Rf 13 and Rf 14 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. Rf 15 and Rf 16 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms. provided that all Rf 15 and Rf 16 It does not become a hydrogen atom at the same time. 17 It is a fluorine atom, a C1 to C6 fluorinated alkyl group, a C1 to C6 fluorinated alkoxy group, a C1 to C6 fluorinated alkylthio group, or a pentafluorosulfanyl group. When e2 is 2, 3, or 4, each Rf 17 They may be identical or different. 41 and R 42 is a hydrocarbyl group having 1 to 20 carbon atoms, which may each independently contain a heteroatom. Also, R 41 and R 42 They may combine with each other to form a ring together with the sulfur atom to which they combine. 43 It is a hydrocarbyl group having 1 to 20 carbon atoms that may contain halogen atoms other than fluorine atoms or heteroatoms. When e3 is 2, 3, or 4, each R 43 They may be identical or different from each other, and multiple R 43 These may bond with each other to form a ring together with the carbon atoms they bond to. - is a non-nucleophilic counterion. + is an onium cation.) Claim 9 In paragraph 5, a chemical amplification resist composition further comprising an organic solvent. Claim 10 In claim 5, additionally, a chemical amplification resist composition comprising a quencher. Claim 11 In paragraph 5, a chemical amplification resist composition comprising, additionally, a photogenerative agent other than the photogenerative agent described in paragraph 4. Claim 12 In paragraph 5, a chemical amplification resist composition further comprising a surfactant. Claim 13 A pattern forming method comprising: a process of forming a resist film on a substrate using a chemically amplified resist composition described in claim 5; a process of exposing the resist film to high-energy rays; and a process of developing the exposed resist film using a developer. Claim 14 A pattern forming method according to claim 13, wherein the high-energy line is KrF excimer laser light, ArF excimer laser light, electron beam, or extreme ultraviolet light with a wavelength of 3 to 15 nm.

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