Chemically amplified resist composition and pattern formation method

Abstract

This invention provides a chemically amplified resist composition that exhibits excellent solvent solubility, high sensitivity, high contrast, and excellent etching resistance in photolithography using high-energy rays, and a pattern formation method using the chemically amplified resist composition. [Solution] A chemically amplified resist composition comprising (A) a polymer containing repeating units represented by the following formula (a1) and not containing repeating units that generate acid upon exposure, (B) a photoacid generator containing an iodine atom or a fluoroalkanesulfonic acid anion having an aromatic ring structure substituted with an iodine atom and a bromine atom, and (C) a solvent. TIFF2026135632000230.tif5174

Description

[Technical Field]

[0001] The present invention relates to a chemically amplified resist composition and a patterning method. [Background technology]

[0002] With the increasing integration and speed of LSIs, the miniaturization of pattern rules is progressing rapidly. In particular, the expansion of the flash memory market and the increase in storage capacity are driving this miniaturization. As for the most advanced miniaturization technology, mass production of 65nm node devices using ArF lithography is underway, and preparations for mass production of next-generation 45nm node devices using ArF immersion lithography are underway. For next-generation 32nm node devices, immersion lithography using ultra-high NA lenses combining a liquid with a higher refractive index than water, a high refractive index lens, and a high refractive index resist film, extreme ultraviolet (EUV) lithography with a wavelength of 13.5nm, and double exposure (double patterning lithography) of ArF lithography are among the candidates and are currently being investigated.

[0003] As miniaturization progresses and approaches the diffraction limit of light, the contrast of light decreases. This decrease in light contrast leads to a reduction in the resolution of hole patterns and trench patterns, as well as a decrease in the focus margin, in positive resist films.

[0004] As patterns become finer, the line width roughness (LWR) of line patterns and the dimensional uniformity (CDU) of hole patterns are becoming problematic. The effects of uneven distribution and aggregation of base polymers and acid generators, as well as the effects of acid diffusion, have been pointed out. Furthermore, LWR tends to increase as the resist film thins, and the degradation of LWR due to thinning as finer patterns progress is becoming a serious problem.

[0005] In resist compositions for EUV lithography, it is necessary to simultaneously achieve high sensitivity, high resolution, and low LWR. Shortening the acid diffusion distance reduces LWR but also lowers sensitivity. For example, lowering the post-exposure bake (PEB) temperature reduces LWR but lowers sensitivity. Increasing the amount of quencher added also reduces LWR but lowers sensitivity. It is necessary to overcome the trade-off relationship between sensitivity and LWR.

[0006] To suppress acid diffusion, resist compounds containing repeating units derived from onium salts of polymerizable unsaturated sulfonic acids have been proposed (Patent Document 1). Such so-called polymer-bound acid generators have the characteristic of very short acid diffusion because polymer-type sulfonic acids are generated upon exposure. Furthermore, sensitivity can be improved by increasing the ratio of the acid generator. In the case of additive-type acid generators, increasing the amount added also increases sensitivity, but in this case the acid diffusion distance also increases. Since acids diffuse non-uniformly, increased acid diffusion degrades LWR and CDU. Polymer-type acid generators can be said to have high capability in balancing sensitivity, LWR, and CDU.

[0007] Because iodine atoms have very high absorption of EUV light at a wavelength of 13.5 nm, the effect of generating secondary electrons from iodine atoms during exposure has been confirmed, and they are attracting attention in EUV lithography. Patent document 2 describes a photoacid generator in which iodine atoms are introduced into an anion, and patent document 3 describes a photoacid generator containing a polymerizable group in which iodine atoms are introduced into an anion. Although some improvement in lithography performance has been confirmed as a result, iodine atoms do not have high solubility in organic solvents, and precipitation in solvents is a concern.

[0008] Patent documents 4 and 5 propose resist materials using polymers copolymerized with polymerizable salicylic acid or its protected form as the base polymer. Patent document 6 proposes a resist material using a base polymer of a monomer in which two adjacent hydroxyl groups of dihydroxystyrene are protected with a cyclic acetal. Salicylic acid has a structure in which a hydroxyl group and a carboxyl group are located on adjacent carbon atoms of the aromatic ring, and the substituents on each other form hydrogen bonds. As a result, it has relatively high solubility in organic solvents despite having two polar groups, and copolymerization with other monomers is relatively easy. However, its performance as a resist material is still unsatisfactory, and there is a need to develop resist materials that are useful for forming even finer patterns. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Patent No. 4425776 [Patent Document 2] Patent No. 6720926 [Patent Document 3] Patent No. 6973274 [Patent Document 4] Japanese Patent Publication No. 2023-131926 [Patent Document 5] International Publication No. 2023 / 162837 [Patent Document 6] Patent No. 7203133 [Overview of the project] [Problems that the invention aims to solve]

[0010] In acid-catalyzed chemically amplified resist compositions, there is a need for the development of resist compositions that offer even higher sensitivity, improve the LWR of line patterns and CDU of hole patterns, and exhibit excellent etching resistance after pattern formation.

[0011] The present invention has been made in view of the above circumstances, and aims to provide a chemically amplified resist composition that exhibits excellent solvent solubility, high sensitivity and high contrast, excellent lithography performance such as LWR, CDU, exposure margin (EL), and depth of focus (DOF) in photolithography using high-energy beams such as KrF excimer laser light, ArF excimer laser light, electron beam (EB), and EUV, and also exhibits excellent resistance to pattern deformation and etching even in the formation of fine patterns, and a method for forming patterns using the chemically amplified resist composition. [Means for solving the problem]

[0012] As a result of diligent research to achieve the above objective, the inventors have discovered that by using a polymer containing repeating units having a cyclic acetal structure fused to an aromatic ring, and a photoacid generator containing an iodine atom or a fluoroalkanesulfonic acid anion having an aromatic ring structure substituted with an iodine atom and a bromine atom, a chemically amplified resist composition can be obtained that is highly sensitive, has improved lithography performance such as LWR, CDU, EL, and DOF, has high contrast and high resolution, and has excellent etching resistance, thus completing the present invention.

[0013] In other words, the present invention provides the following chemically amplified resist composition and pattern formation method. 1. (A) A polymer containing repeating units represented by the following formula (a1), and not containing repeating units that generate acid upon exposure. (B) A photoacid generator containing an iodine atom or a fluoroalkanesulfonate anion having an aromatic ring structure substituted with an iodine atom and a bromine atom, and (C) Organic solvents A chemically amplified resist composition containing the following: [ka] (In the formula, a1 is either 0 or 1. When a1 is 0, a2 is 0, 1, 2, or 3, and when a1 is 1, a2 is 0, 1, 2, 3, 4, or 5.) R Ais a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. X 1 is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-. * represents a bond to a carbon atom in the main chain. X 2 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 combining these. X 3 and X 4 are each independently an oxygen atom or a sulfur atom. However, X 2 and X 4 are bonded to adjacent carbon atoms of an aromatic ring. R 1 and R 2 are each independently a hydrogen atom or a hydrocarbyl group having 1 to 20 carbon atoms which may contain a heteroatom. Also, R 1 and R 2 may combine with each other to form a ring together with the carbon atom to which they are bonded. R 3 is a halogen atom, a hydroxy group, a cyano group, a nitro group, a pentafluorosulfanyl group, a hydrocarbyl group having 1 to 20 carbon atoms which may contain a heteroatom, a hydrocarbyloxy group having 1 to 20 carbon atoms which may contain a heteroatom, a hydrocarbyloxycarbonyl group having 2 to 20 carbon atoms which may contain a heteroatom, a hydrocarbylthio group having 1 to 20 carbon atoms which may contain a heteroatom or -N(R 3A )(R 3B ). R 3A and R 3B are each independently a hydrogen atom or a hydrocarbyl group having 1 to 6 carbon atoms. When a2 is 2 or more, each R 3 may be the same as or different from each other, and a plurality of R 3 may combine with each other to form a ring together with the carbon atom of the aromatic ring to which they are bonded. ) 2. X 3 and X 4 are both oxygen atoms, a chemically amplified resist composition. 3. X 2However, a chemically amplified resist composition comprising 1 or 2 carbonyl groups. 4. A chemically amplified resist composition of any of 1 to 3 wherein the photoacid generator is represented by the following formula (1). [ka] (In the equation, x is 1, 2, or 3. y is 1, 2, 3, 4, or 5.) z is 0, 1, 2, or 3, where 1 ≤ y + z ≤ 5. X BI When y is 1, it is an iodine atom, and when y is 2, 3, 4, or 5, it is an iodine atom or a bromine atom, but at least one of them is an iodine atom. L 1 This is a single bond, ether bond, ester bond, sulfonic acid ester bond, sulfonamide bond, amide bond, carbonate bond, 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, ester bond, sulfonic acid ester bond, sulfonamide bond, amide bond, carbonate bond, or carbamate bond. L 2 When x is 1, it is a C1-C20 hydrocarbylene group which may contain a single bond or a heteroatom, and when x is 2 or 3, it is a C1-C20 (x+1) valent hydrocarbon group which may contain a heteroatom. L 3 These are single bonds, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, or carbamate bonds. R 101 This includes a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a pentafluorosulfanyl group, a C1-C20 hydrocarbyl group, a C1-C20 hydrocarbyloxy group, a C1-C20 hydrocarbylthio group, a C2-C20 hydrocarbylcarbonyl group, a C2-C20 hydrocarbyloxycarbonyl group, a C2-C20 hydrocarbylcarbonyloxy group, a C1-C20 hydrocarbylsulfonyloxy group, and -N(R 101A )(R 101B), -N(R 101C )-C(=O)-R 101D or -N(R 101C )-C(=O)-OR 101D The hydrocarbyl group, hydrocarbyloxy group, hydrocarbylthio group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may contain at least one selected from fluorine, chlorine, bromine, iodine, hydroxyl, amino, ester, and ether bonds. 101A and R 101B Each of these is independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. 101C R is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may also contain 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. 101D This 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 also contain 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. Rf 1 ~Rf 4 Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is either a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 (These may combine to form a carbonyl group.) Z + (This is an onium cation.) 5.Z + A chemically amplified resist composition of any of 1 to 4, wherein the sulfonium cation is represented by the following formula (Z-1) or the iodonium cation is represented by the following formula (Z-2). [ka] (In the formula, R ct1 ~R ct5 Each of these is independently a hydrocarbyl group having 1 to 30 carbon atoms, which may contain a halogen atom or a heteroatom. Also, R ct1 and R ct2 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. 6.Z + However, it is an onium salt of any of 1 to 5, which are sulfonium cations represented by the following formula (Z-3). [ka] (In the formula, m1 is 0 or 1. m2 is 0 or 1. m3 is 0 or 1. m4 is 0, 1, 2, 3 or 4. m5 is 0, 1, 2, 3 or 4. m6 is 0, 1, 2, 3, 4, 5 or 6. m7 is 0, 1, 2, 3, 4, 5 or 6. m8 is 0, 1 or 2. m9 is 0, 1 or 2. m10 is 0, 1 or 2. m11 is 0 or 1. m12 is 0, 1, 2, 3 or 4. m13 is 0, 1 or 2. m14 is 0, It is either 1 or 2. However, when m1 is 0, 0 ≤ m6 + m9 ≤ 4, and when m1 is 1, 0 ≤ m6 + m9 ≤ 6. When m2 is 0, 0 ≤ m7 + m10 ≤ 4, and when m2 is 1, 0 ≤ m7 + m10 ≤ 6. When m3 is 0, 1 ≤ m4 + m5 + m8 + m14 ≤ 4, and when m3 is 1, 1 ≤ m4 + m5 + m8 + m14 ≤ 6. When m11 is 0, 0 ≤ m12 + m13 ≤ 4, and when m11 is 1, 0 ≤ m12 + m13 ≤ 6. Also, m4 + m12 ≥ 1. R F1 ~R F3 Each of these 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. When m5 is 2, 3, or 4, each R F1 They may be the same or different from each other. When m6 is 2, 3, 4, 5 or 6, each R F2 They may be the same or different from each other. When m7 is 2, 3, 4, 5 or 6, each RF3 They may be the same as or different from each other. R ct6 ~R ct9 This is a C1-C20 hydrocarbyl group which may contain halogen atoms other than iodine and fluorine atoms, a nitro group, a cyano group, a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, or a C1-C20 hydrocarbylthio group which may contain a heteroatom. When m8 is 2, two R ct6 The two Rs may be identical or different from each other. ct6 These may bond with each other to form a ring with the carbon atom to which they are bonded. When m9 is 2, two R ct7 The two Rs may be identical or different from each other. ct7 These may bond with each other to form a ring with the carbon atom to which they are bonded. When m10 is 2, two R ct8 The two Rs may be identical or different from each other. ct8 These may bond with each other to form a ring with the carbon atoms to which they are bonded. When m13 is 2, two R ct9 The two Rs may be identical or different from each other. ct9 These atoms may bond with each other to form a ring with the carbon atoms to which they are bonded. Also, S in sulfonium cations + Aromatic rings that are directly bonded to each other are bonded to each other, forming S + They may form a ring together. L A and L B These are, independently, a single bond, an ether bond, an ester bond, an amide bond, a sulfonic acid ester bond, a sulfonamide bond, a carbonate bond, or a carbamate bond. X L This is a hydrocarbylene group having 1 to 40 carbon atoms, which may contain single bonds or heteroatoms. 7. Any of the chemical amplification resist compositions 1 to 6, wherein the polymer further comprises at least one selected from repeating units represented by the following formula (a2) and repeating units represented by the following formula (a3). [ka] (In the formula, R A These are, independently, a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. X 5 This refers to a single bond, a phenylene group, a naphthylene group, or *-C(=O)-OX 51 -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 which may contain a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms which may contain a fluorine atom, or a halogen atom. 51 This is a saturated hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. X 6 These are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-. * represents a bond with a carbon atom in the main chain. R 11 This is a halogen atom, a cyano group, a hydroxyl group, a nitro group, a pentafluorosulfanyl group, a C1-C20 hydrocarbyl group which may contain a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyl group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or a C2-C20 hydrocarbyloxycarbonyl group which may contain a heteroatom. When b1 is 2, 3, or 4, each R 11 They may be the same as or different from each other. AL 1 and AL 2 These are, independently, acid-unstable groups. b1 is 0, 1, 2, 3, or 4. 8. Any of the chemically amplified resist compositions 1 to 7 wherein the polymer further comprises repeating units represented by the following formula (b). [ka] (In the formula, R A These are a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Y 1 The bonds are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-. The asterisk (*) represents a bond with a carbon atom in the main chain. R 21 This is a halogen atom, a carboxyl group, a nitro group, a cyano group, a pentafluorosulfanil group, a C1-C20 hydrocarbyl group which may contain a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyl group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or a C2-C20 hydrocarbyloxycarbonyl group which may contain a heteroatom. When c2 is 2, 3, or 4, each R 21 They may be the same as or different from each other. c1 is 1, 2, 3, or 4. c2 is 0, 1, 2, 3, or 4, where 1 ≤ c1 + c2 ≤ 5. 9. Any of the chemically amplified resist compositions 1 to 8, wherein the polymer further comprises repeating units represented by the following formula (c). [ka] (In the formula, R A These are a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z 1 This consists of a single bond, a phenylene group, a naphthylene group, and *-C(=O)-OZ 11 -or *-C(=O)-N(H)-Z 11 -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 which may contain a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms which may contain a fluorine atom, or a halogen atom. * represents a bond with a carbon atom of the main chain. Z 11This is a saturated hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. R 31 This refers to a group having 1 to 20 carbon atoms that includes 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 sultone ring, and a carboxylic acid anhydride (-C(=O)-OC(=O)-). 10. Furthermore, any of the chemically amplified resist compositions 1 to 9, comprising (D) a quencher. 11. Furthermore, (E) any of the chemically amplified resist compositions 1 to 10 comprising other acid generators. 12. Furthermore, any of the chemically amplified resist compositions 1 to 11 comprising (F) a surfactant. A pattern forming method comprising the steps of: forming a resist film on a substrate using any of the chemically amplified resist compositions described in 13.1 to 12; exposing the resist film with high-energy rays; and developing the exposed resist film using a developer. 14. A pattern formation method comprising 13 wherein the high-energy beam is ArF excimer laser light with a wavelength of 193 nm, KrF excimer laser light with a wavelength of 248 nm, an electron beam, or extreme ultraviolet light with a wavelength of 3 to 15 nm. [Effects of the Invention]

[0014] When pattern formation is performed using the chemically amplified resist composition of the present invention, high sensitivity, excellent acid diffusion suppression ability, improved lithography performance such as LWR, CDU, MEF, EL, and DOF are achieved, and resist pattern collapse and development defects during fine pattern formation can be suppressed. Furthermore, a resist pattern with high resistance can be formed even in the etching process. [Modes for carrying out the invention]

[0015] [Chemically amplified resist composition] [(A) Base polymer] The chemically amplified resist composition of the present invention contains a base polymer as component (A). The base polymer contains a repeating unit represented by the following formula (a1) (hereinafter, also referred to as repeating unit a1). [Chemical formula]

[0016] In formula (a1), a1 is 0 or 1. When a1 is 0, it is a benzene ring, and when a1 is 1, it is a naphthalene ring. From the viewpoint of solvent solubility, it is preferably a benzene ring where a1 is 0. When a1 is 0, a2 is 0, 1, 2 or 3, and when a1 is 1, a2 is 0, 1, 2, 3, 4 or 5. From the viewpoint of raw material procurement, a2 is preferably 0, 1, 2 or 3, and more preferably 0, 1 or 2.

[0017] In formula (a1), R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. As R A , it is preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom. )]

[0018] In formula (a1), X 1 )]is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-. * represents a bond to a carbon atom of the main chain. Among these, a single bond and *-C(=O)-O- are preferable, and a single bond is more preferable. -C(=O)-), a haloalkyl group, etc. may be included.

[0019] In formula (a1), X 2 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 combining these. Among these, from the viewpoint of raw material procurement, a single bond, a carbonyl group or a sulfonyl group is preferable, and from the viewpoint of the polar group generated after the reaction, a single bond or a carbonyl group is more preferable.

[0020] In formula (a1), X 3 and X 4 are each independently an oxygen atom or a sulfur atom. However, X 2 and X 4 are bonded to adjacent carbon atoms of the aromatic ring. X 3 and X 4 may be the same as or different from each other. From the viewpoint of reactivity, it is preferable that both X 3 and X 4 are oxygen atoms.

[0021] In formula (a1), R 1 and R 2Each of these is a C1-C20 hydrocarbyl group which may independently contain a hydrogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include C1-C20 alkyl groups 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 eicosyl; cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, and 4-methylcyclo Examples include cyclic saturated hydrocarbyl groups with 3 to 20 carbon atoms, such as hexyl, cyclohexylmethyl, norbornyl, and adamantyl groups; alkenyl groups with 2 to 20 carbon atoms, such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl groups; cyclic unsaturated hydrocarbyl groups with 3 to 20 carbon atoms, such as cyclohexenyl groups; aryl groups with 6 to 20 carbon atoms, such as phenyl and naphthyl groups; aralkyl groups with 7 to 20 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl groups; and groups obtained by combining these. 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- groups of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, the material may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, lactone rings, sultone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0022] Also, R 1 and R 2These may bond with each other to form a ring with the carbon atoms to which they are bonded. Specific examples of the ring formed in this case include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a norbornane ring, an adamantane ring, and so on. Furthermore, some or all of the hydrogen atoms in the ring may be substituted with a group containing a heteroatom 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 a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. As a result, the ring may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, and so on.

[0023] In formula (a1), R 3 This may include halogen atoms, hydroxyl groups, cyano groups, nitro groups, pentafluorosulfanyl groups, C1-C20 hydrocarbyl groups which may contain heteroatoms, C1-C20 hydrocarbyloxy groups which may contain heteroatoms, C2-C20 hydrocarbyloxycarbonyl groups which may contain heteroatoms, C1-C20 hydrocarbylthio groups which may contain heteroatoms, or -N(R 3A )(R 3B ) is R 3A and R 3B Each of these 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 hydrocarbyloxy group, hydrocarbyloxycarbonyl group and hydrocarbylthio group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R 1 and R 2Examples of hydrocarbyl groups represented by the above are similar to those exemplified. 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, and halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, and nitrogen atoms, and as a result, it may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. When a2 is 2 or more, each R 3 They may be the same as or different from each other.

[0024] Also, when a2 is 2 or more, multiple R 3 However, they may bond with each other to form a ring together with the carbon atoms of the aromatic ring to which they are bonded. Specific examples of the ring formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornane rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the ring may be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and some of the -CH2- in the ring may be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc., and as a result, the ring may contain 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, sultone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0025] Specific examples of repeating unit a1 are shown below, but are not limited to these. Note that in the following formula, R A The same as described above, where Me is a methyl group. Furthermore, the bonding positions of the various substituents on the aromatic ring may be interchanged. [ka]

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[0075] In the chemically amplified resist composition of the present invention, as a structural feature of the (A) base polymer, it may include a repeating unit a1 having a cyclic acetal structure fused to an aromatic ring. The cyclic acetal structure fused to the aromatic ring has good solvent solubility and also acts as an acid-labile group, so that a deprotection reaction proceeds by the action of an acid to generate two polar groups. This improves the contrast between the exposed portion and the unexposed portion. Further, since the two generated polar groups are bonded to adjacent carbon atoms to each other, the hydroxy group or the carboxy group forms a hydrogen bond with each other. Thereby, swelling by an alkaline developer during alkali development can be suppressed, and collapse of the resist pattern in the unexposed portion can be suppressed. The cyclic acetal structure fused to the aromatic ring remaining in the unexposed portion has a bicyclo ring structure, so that high resistance is exhibited even in an etching process. Since the polymer before exposure has high solvent solubility of the cyclic acetal structure contained in the repeating unit a1, precipitation etc. in the solvent are suppressed, and when developing with an alkaline developer after exposure, the polar groups generated after deprotection of the acetal structure have high affinity for the alkaline developer, so that the exposed portion is effectively removed and the risk of development defects is reduced.

[0076] On the other hand, onium salts containing fluorosulfonic acid anions with an aromatic ring structure substituted with iodine atoms have a large excluded volume and act as bulky substituents, highly suppressing the diffusion of generated acids. Since iodine atoms are elements with a high absorption effect of EUV light, the amount of secondary electrons generated increases, promoting cation decomposition and contributing to higher sensitivity. Also, since iodine atoms are elements with a large molecular weight, they highly suppress the diffusion of generated acids. Furthermore, since iodine atoms are resistant to alkaline developers, they reduce film thinning of the pattern in unexposed areas. Although not as much as iodine atoms, fluorine atoms in fluoroalkanesulfonic acid anions are elements with a high absorption effect of EUV light, so increasing the number of fluorine atoms increases the amount of secondary electrons generated, promoting cation decomposition and contributing to higher sensitivity. Due to these synergistic effects, the chemically amplified resist composition of the present invention has excellent LWR of line patterns and CDU of hole patterns, fewer development defects, and enables pattern formation that is resistant to pattern collapse, making it particularly suitable as a material for chemically amplified positive-type resist compositions.

[0077] The polymer may further include at least one selected from the repeating units represented by the following formula (a2) (hereinafter also referred to as repeating unit a2) and the repeating unit represented by the following formula (a3) ​​(hereinafter also referred to as repeating unit a3). [ka]

[0078] In equations (a2) and (a3), R A These are, independently, a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0079] In formula (a2), X 5 This refers to a single bond, a phenylene group, a naphthylene group, or *-C(=O)-OX 51-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 which may contain a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms which may contain a fluorine atom, or a halogen atom. 51 This is a saturated hydrocarbylene group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. * represents a bond with a carbon atom of the main chain.

[0080] In formula (a3), X 6 The bond is a single bond, *-C(=O)-O-, or *-C(=O)-N(H)-. * represents a bond with a carbon atom in the main chain. 11 b1 is a halogen atom, a cyano group, a hydroxyl group, a nitro group, a pentafluorosulfanil group, a C1-C20 hydrocarbyl group which may contain a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyl group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or a C2-C20 hydrocarbyloxycarbonyl group which may contain a heteroatom. b1 is 0, 1, 2, 3, or 4, preferably 0 or 1. When b1 is 2, 3, or 4, each R 11 They may be the same as or different from each other.

[0081] In formulas (a2) and (a3), AL 1 and AL 2 Each of these is independently an acid-unstable group. Specific examples of the acid-unstable groups include those described in Japanese Patent Publication No. 2013-80033 and Japanese Patent Publication No. 2013-83821.

[0082] Typical examples of the acid-unstable group include those represented by the following formulas (AL-1) to (AL-3). [ka] (In the formula, * represents a coupling.)

[0083] In equations (AL-1) and (AL-2), R L1 and R L2 Each of these 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 linear, branched, or cyclic. The hydrocarbyl group is preferably one having 1 to 20 carbon atoms.

[0084] In formula (AL-1), b2 is an integer between 0 and 10, preferably 1, 2, 3, 4, or 5.

[0085] In formula (AL-2), R L3 and R L4 Each of these 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. Also, R L2 , R L3 and R L4 Any two of these may bond with each other to form a ring having 3 to 20 carbon atoms, together with the carbon atom to which they are bonded, or a carbon atom and an oxygen atom. The ring is preferably a ring having 4 to 16 carbon atoms, and an alicyclic ring is particularly preferred.

[0086] In formula (AL-3), R L5 , R L6 and R L7 Each of these is independently a hydrocarbyl group having 1 to 20 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 linear, branched, or cyclic. Also, R L5 , R L6 and R L7 Any two of these may bond with each other to form a ring with 3 to 20 carbon atoms. The ring is preferably a ring with 4 to 16 carbon atoms, and an alicyclic ring is particularly preferred.

[0087] Other specific examples of the acid-labile group include those described in paragraphs

[0064] to

[0068] of JP-A No. 2023-123222 and those described in paragraphs

[0013] to

[0014] of Japanese Patent No. 7492842. These use the formation of a conjugated olefin or an acrylate derivative after the acid elimination reaction as the driving force for the reaction progress.

[0088] Specific examples of the repeating unit a2 include, but are not limited to, those shown below. In the following formulas, R A and AL 1 are the same as described above.

Chemical formula

[0089]

Chemical formula

[0090]

Chemical formula

[0091]

Chemical formula

[0092] [[ID=4〕] Specific examples of the repeating unit a3 include, but are not limited to, those shown below. In the following formulas, R A and AL 2 are the same as described above. <00`00984>

Chemical formula

[0093] [[ID=S9]]

Chemical formula

[0094] [ka]

[0095] The polymer may further contain repeating units represented by the following formula (b) (hereinafter also referred to as repeating unit b). [ka]

[0096] In formula (b), R A These are, independently, a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 The bond is a single bond, *-C(=O)-O-, or *-C(=O)-N(H)-. * represents a bond with a carbon atom in the main chain. 21 This is a halogen atom, a carboxyl group, a nitro group, a cyano group, a pentafluorosulfanil group, a C1-C20 hydrocarbyl group which may contain a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyl group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or a C2-C20 hydrocarbyloxycarbonyl group which may contain a heteroatom. When c2 is 2, 3, or 4, each R 21 c1 and c2 may be the same or different from each other. c1 is 1, 2, 3, or 4. c2 is 0, 1, 2, 3, or 4, where 1 ≤ c1 + c2 ≤ 5.

[0097] Specific examples of repeating unit b are shown below, but are not limited to these. Note that in the following formula, R A This is the same as described above. [ka]

[0098] [ka]

[0099] [ka]

[0100] [ka]

[0101] [ka]

[0102] Preferably, the polymer further contains a repeating unit represented by the following formula (c) (hereinafter also referred to as repeating unit c). [ka]

[0103] In formula (c), R A This is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 This consists of a single bond, a phenylene group, a naphthylene group, and *-C(=O)-OZ 11 -or *-C(=O)-N(H)-Z 11 -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 which may contain a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms which may contain a fluorine atom, or a halogen atom. * represents a bond with a carbon atom of the main chain. Z 11 This is a saturated hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. R 31This is a group having 1 to 20 carbon atoms that includes a hydrogen atom or at least one structure selected from 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 sultone ring, and a carboxylic acid anhydride (-C(=O)-OC(=O)-).

[0104] Specific examples of repeating units c are shown below, but are not limited to these. Note that in the following formula, R A This is the same as described above. [ka]

[0105] [ka]

[0106] [ka]

[0107] [ka]

[0108] [ka]

[0109] [ka]

[0110] [ka]

[0111] [ka]

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] [ka]

[0117] [ka]

[0118] [ka]

[0119] [ka]

[0120] In ArF lithography, it is preferable to use repeating units c having a lactone ring as a polar group, while in KrF lithography, EB lithography, and EUV lithography, it is preferable to use repeating units b having a phenol moiety.

[0121] The polymer may further contain repeating units (hereinafter also referred to as repeating unit d) having a structure in which a hydroxyl group is protected by an acid-unstable group. The repeating unit d is not particularly limited as long as it has one or more structures in which a hydroxyl group is protected and the protecting group decomposes upon the action of an acid to generate a hydroxyl group, but it is preferably represented by the following formula (d1). [ka]

[0122] In formula (d1), R A R is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 41 R is a (d+1) valent hydrocarbon group having 1 to 30 carbon atoms, which may contain heteroatoms. 42 is an acid-unstable group. d is 1, 2, 3, or 4.

[0123] In formula (d1), R 42 The acid-unstable group represented by can be any group that is deprotected by the action of an acid and generates a hydroxyl group. 52 The structure is not particularly limited, but acetal structures, ketal structures, hydrocarbyloxycarbonyl groups, and hydrocarbyloxymethyl groups represented by the following formula (d2) are preferred, and the hydrocarbyloxymethyl group represented by the following formula (d2) is particularly preferred. [ka] (In the formula, * represents a bond. R 43 (This refers to a hydrocarbyl group with 1 to 15 carbon atoms.)

[0124] R 42 Specific examples of the acid-unstable group represented by formula (d2), the hydrocarbyloxymethyl group represented by formula (d2), and the repeating unit d are the same as those exemplified in the description of the repeating unit d described in Japanese Patent Application Publication No. 2020-111564.

[0125] The polymer may further contain a repeating unit e derived from indene, benzofuran, benzothiophene, acenaphthylene, chromone, coumarin, norbornadiene or derivatives thereof. Specific examples of the monomer that gives the repeating unit e include, but are not limited to, those shown below. [Chemical formula]

[0126] The polymer may contain a repeating unit f derived from styrene, indane, vinyl pyridine or vinyl carbazole.

[0127] In the polymer of the present invention, the content ratios of the repeating units a1, a2, a3, b, c, d, e and f are preferably 0 < a1 ≤ 0.6, 0 ≤ a2 ≤ 0.6, 0 ≤ a3 ≤ 0.6, 0 ≤ b ≤ 0.6, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 0.3 and 0 ≤ f ≤ 0.3, and more preferably 0 < a1 ≤ 0.5, 0 ≤ a2 ≤ 0.5, 0 ≤ a3 ≤ 0.5, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.4, 0 ≤ d ≤ 0.5, 0 ≤ e ≤ 0.2 and 0 ≤ f ≤ 0.2. However, a1 + a2 + a3 + b + c + d + e + f ≤ 1.0.

[0128] The weight average molecular weight (Mw) of the polymer is preferably from 1000 to 500000, more preferably from 3000 to 100000. If Mw is within this range, sufficient etching resistance can be obtained, and there is no risk of deterioration of resolution due to the inability to ensure the difference in dissolution rate before and after exposure. 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.

[0129] ]The molecular weight distribution (Mw / Mn) of the polymer tends to have a greater influence as the pattern rule becomes finer. Therefore, in order to obtain a resist composition suitable for fine pattern dimensions, it is preferable that the Mw / Mn is narrowly dispersed between 1.0 and 2.0. Within this range, there are few low molecular weight or high molecular weight polymers, and there is no risk of foreign matter being observed on the pattern or deterioration of the pattern shape after exposure.

[0130] One example of a method for synthesizing the aforementioned polymer is to heat a monomer that provides the repeating units described above in an organic solvent with a radical polymerization initiator added, and polymerize it.

[0131] 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), and γ-butyrolactone (GBL). Specific examples of polymerization initiators include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl-2,2-azobis(2-methylpropionate), 1,1'-azobis(1-acetoxy-1-phenylethane), benzoyl peroxide, and lauroyl peroxide. The amount of these initiators added is preferably 0.01 to 25 mol% of 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 viewpoint of production efficiency.

[0132] The polymerization initiator may be added to the monomer solution and supplied to the reaction vessel, or an initiator solution may be prepared separately from the monomer solution and each supplied to the reaction vessel independently. Since the polymerization reaction may proceed and a superpolymer may be formed by radicals generated from the initiator during the waiting time, it is preferable from a quality control viewpoint to prepare the monomer solution and the initiator solution independently and add them dropwise. The acid-unstable group may be used as is, introduced into the monomer, or it may be protected or partially protected after polymerization. In addition, 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% of the total amount of monomers to be polymerized.

[0133] 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 then deprotected with a weak acid and water after polymerization. Alternatively, they may be substituted with acetyl groups, formyl groups, pivaloyl groups, etc., and then alkaline hydrolysis may be performed after polymerization.

[0134] When copolymerizing hydroxystyrene or hydroxyvinylnaphthalene, hydroxystyrene or hydroxyvinylnaphthalene may be polymerized by heating in an organic solvent with a radical polymerization initiator. Alternatively, acetoxystyrene or acetoxyvinylnaphthalene may be used, and after polymerization, the acetoxy group may be deprotected by alkaline hydrolysis to obtain polyhydroxystyrene or hydroxypolyvinylnaphthalene.

[0135] Specific examples of bases that can be used during alkaline hydrolysis include aqueous ammonia and triethylamine. 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.

[0136] The amount of each monomer in the monomer solution can be appropriately set, for example, to achieve a preferred content ratio of the repeating units described above.

[0137] The polymer obtained by the above manufacturing method may be treated as a final product if it is a reaction solution obtained by a polymerization reaction, or as a final product if it is a powder obtained by a purification process such as a reprecipitation method in which the polymerization solution is added to a poor solvent and a powder is obtained. However, from the viewpoint of work efficiency and quality stabilization, it is preferable to treat the polymer solution obtained by dissolving the powder obtained by the purification process in a solvent as the final product.

[0138] Specific examples of solvents used in this process 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; 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 ethers such as ethers; 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 alcoholic solvents such as diethylene glycol, propylene glycol, glycerin, 1,4-butanediol, and 1,3-butanediol; and mixed solvents thereof.

[0139] In the polymer solution, the concentration of the polymer is preferably 0.01 to 30% by mass, and more preferably 0.1 to 20% by mass.

[0140] It is preferable to filter the reaction solution or polymer solution. Filtering removes foreign matter and gel that may cause defects, which is effective in stabilizing quality.

[0141] Examples of filter materials used in the aforementioned filter filtration include fluorocarbon, cellulose, nylon, polyester, and hydrocarbon materials. However, in the filtration process of chemically amplified resist compositions, filters made of fluorocarbon materials such as Teflon (registered trademark), hydrocarbon materials such as polyethylene and polypropylene, or nylon are preferred. The pore size of the filter can be appropriately selected according to the desired level of cleanliness, but is preferably 100 nm or less, and more preferably 20 nm or less. These filters may be used individually or in combination. The filtration method may involve passing the solution through only once, but it is more preferable to circulate the solution and filter it multiple times. The filtration process can be carried out in any order and number of times in the polymer manufacturing process, but it is preferable to filter the reaction solution after the polymerization reaction, the polymer solution, or both.

[0142] (A) The base polymer may be used alone, or two or more types with different composition ratios, Mw and / or Mw / Mn may be used in combination. In addition, (A) the base polymer may also contain hydrogenated ring-opening metathesis polymers, for which those described in Japanese Patent Publication No. 2003-66612 may be used.

[0143] [(B) Photoacid Generator] The chemically amplified resist composition of the present invention comprises a photoacid generator containing an iodine atom or a fluoroalkanesulfonic acid anion having an aromatic ring structure substituted with an iodine atom and a bromine atom. The photoacid generator is particularly preferably represented by the following formula (1). [ka]

[0144] In equation (1), x is 1, 2, or 3. y is 1, 2, 3, 4, or 5. z is 0, 1, 2, or 3, where 1 ≤ y + z ≤ 5. y is preferably 1, 2, or 3, more preferably 2 or 3. z is preferably 0, 1, or 2.

[0145] In formula (1), X BI When y is 1, it is an iodine atom, and when y is 2, 3, 4, or 5, it is an iodine atom or a bromine atom, but at least one of them is an iodine atom.

[0146] In formula (1), L 1 This is a single bond, ether bond, ester bond, sulfonic acid ester bond, sulfonamide bond, amide bond, carbonate bond, 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, ester bond, sulfonic acid ester bond, sulfonamide bond, amide bond, carbonate bond, or carbamate bond. The saturated hydrocarbylene group may be linear, branched, or cyclic.

[0147] In formula (1), L 2 When x is 1, it is a C1-C20 hydrocarbylene group which may contain a single bond or a heteroatom, and when x is 2 or 3, it is a C1-C20 (x+1) valent hydrocarbon group which may contain a heteroatom.

[0148] L 2The C1-C20 hydrocarbylene group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include C1-C20 alkanediyl groups such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl; cyclopentanediyl, cyclohexanediyl, norbornanediyl, adamantanediyl, tricyclo[5.2.1.0 2,6 Examples include cyclic saturated hydrocarbylene groups with 3 to 20 carbon atoms, such as decanediyl groups; unsaturated aliphatic hydrocarbylene groups with 2 to 20 carbon atoms, such as vinylene groups and propene-1,3-diyl groups; arylene groups with 6 to 20 carbon atoms, such as phenylene groups, naphthylene groups, and anthracenediyl groups; aromatic ring-containing polycyclic hydrocarbylene groups with 7 to 20 carbon atoms, such as 9,10-ethano-9,10-dihydroanthracenediyl groups and 6,13-ethano-6,13-dihydropentacene groups; and groups obtained by combining these. 2 The (x+1) valent hydrocarbon group having 1 to 20 carbon atoms, represented by , may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include groups obtained by removing one or two hydrogen atoms from the aforementioned specific examples of the 1 to 20 carbon atom hydrocarbylene group.

[0149] Furthermore, some or all of the hydrogen atoms of the hydrocarbylene group and the (x+1) valent hydrocarbon group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbylene group and the (x+1) valent hydrocarbon group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, the material may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0150] In formula (1), L 3 These are single bonds, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, or carbamate bonds.

[0151] In formula (1), R 101 This includes a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a pentafluorosulfanyl group, a C1-C20 hydrocarbyl group, a C1-C20 hydrocarbyloxy group, a C1-C20 hydrocarbylthio group, a C2-C20 hydrocarbylcarbonyl group, a C2-C20 hydrocarbyloxycarbonyl group, a C2-C20 hydrocarbylcarbonyloxy group, a C1-C20 hydrocarbylsulfonyloxy group, and -N(R 101A )(R 101B ), -N(R 101C )-C(=O)-R 101D or -N(R 101C )-C(=O)-OR 101D The hydrocarbyl group, hydrocarbyloxy group, hydrocarbylthio group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may contain at least one selected from fluorine, chlorine, bromine, iodine, hydroxyl, amino, ester, and ether bonds. 101A and R 101BEach of these is independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. 101C R is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may also contain 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. 101D This 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 contain 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 linear, branched, or cyclic. The hydrocarbyl group, hydrocarbyloxy group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may be linear, branched, or cyclic. When x and / or z is 2 or more, each R 101 They may be the same as or different from each other.

[0152] Of these, R 101 Examples include hydroxyl groups, -N(R 101C )-C(=O)-R 101D , -N(R 101C )-C(=O)-OR 101D Fluorine atoms, chlorine atoms, bromine atoms, methyl groups, methoxy groups, etc. are preferred.

[0153] In formula (1), Rf 1 ~Rf 4 Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is either a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 These may combine to form a carbonyl group. In particular, Rf 3 and Rf 4 It is preferable that both are fluorine atoms.

[0154] Specific examples of the anion of the photoacid generator represented by formula (1) are listed below, but are not limited to these. Note that in the following formula, X BI This is the same as described above. [ka]

[0155] [ka]

[0156] [ka]

[0157] [ka]

[0158] [ka]

[0159] [ka]

[0160] [ka]

[0161] [ka]

[0162] [ka]

[0163] [ka]

[0164]

change

[0165]

change

[0166]

change

[0167]

change

[0168]

change

[0169]

change

[0170]

change

[0171]

change

[0172]

change

[0173]

change

[0174]

change

[0175]

change

[0176]

change

[0177]

change

[0178] Other examples of the photoacid generator anion represented by formula (1) include 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, and paragraph

[0026] of Japanese Patent Publication No. 2024-62406. ~

[0028] , paragraphs of Japanese Patent Publication No. 2024-62407

[0022] ~

[0025] , paragraphs of Japanese Patent Publication No. 2024-62408

[0026] ~

[0028] , paragraphs of Japanese Patent Publication No. 2024-68156

[0028] ~

[0030] , paragraphs of Japanese Patent Publication No. 2024-68157

[0026] ~

[0028] , paragraphs of Japanese Patent Publication No. 2024-68158

[0028] ~

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

[0028] ~

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

[0031] ~

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

[0023] ~

[0025] , paragraphs of JP 2024-77618,

[0026] ~

[0029] , paragraphs of JP 2024-77619,

[0020] ~

[0021] , paragraphs of JP 2024-80672,

[0140] ~

[0143] , paragraphs of JP 2024-83303,

[0023] ~

[0025] , paragraphs of JP 2024-83304,

[0028] ~

[0031] , paragraphs of JP 2024-99500,

[0030] ~

[0033] , paragraphs of JP 2024-99502,

[0028] ~

[0030] , JP 2024-1015 Paragraphs

[0030] to

[0032] of Patent Publication No. 57, paragraphs

[0025] to

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

[0033] to

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

[0021] to

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

[0169] to

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

[0178] to

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

[0040] to

[0143] of Japanese Unexamined Patent Publication No. 2024-160436, paragraphs

[0157] to

[0158] of Japanese Patent Publication No. 7247732,Examples include those described in 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.

[0179] In formula (1), Z + This is an onium cation. The onium cation is preferably a sulfonium cation represented by the following formula (Z-1) or an iodonium cation represented by the following formula (Z-2). [ka]

[0180] In equations (Z-1) and (Z-2), R ct1 ~R ct5 Each of these is independently a hydrocarbyl group having 1 to 30 carbon atoms, which may contain a halogen atom or a heteroatom.

[0181] R ct1 ~R ct5 Specific examples of halogen atoms represented by this formula include fluorine, chlorine, bromine, and iodine atoms.

[0182] R ct1 ~R ct5The hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include C1-C30 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl groups; C3-C30 cyclic saturated hydrocarbyl groups such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, and adamantyl groups; C2-C30 alkenyl groups such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl groups; C3-C30 cyclic unsaturated hydrocarbyl groups such as cyclohexenyl; C6-C30 aryl groups such as phenyl, naphthyl, and thienyl groups; C7-C30 aralkyl groups such as benzyl, 1-phenylethyl, and 2-phenylethyl groups; and groups obtained by combining these, but aryl groups are preferred. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a pentafluorosulfanyl group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0183] Also, R ct1 and R ct2 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. In this case, specific examples of the structure of the ring include those represented by the following formula. [ka] (In the formula, the dashed line represents R ct3 (This is a combination of the two.)

[0184] Specific examples of sulfonium cations represented by formula (Z-1) include those described in paragraphs

[0102] to

[0125] of Japanese Patent Publication No. 2024-003744 and those described in paragraphs

[0070] to

[0085] of Japanese Patent Publication No. 2023-169812, but are not limited to these.

[0185] Specific examples of iodonium cations represented by formula (Z-2) include, but are not limited to, those described in paragraph

[0181] of Japanese Patent Application Publication No. 2024-000259.

[0186] Z + As the onium cation represented by the following formula (Z-3), a sulfonium cation represented by the following formula is also preferred. [ka]

[0187] In formula (Z-3), m1 is either 0 or 1. When m1 is 0, it is a benzene ring, and when m1 is 1, it is a naphthalene ring, but from the viewpoint of solvent solubility, it is preferable that m1 is a benzene ring with a value of 0. m2 is either 0 or 1. When m2 is 0, it is a benzene ring, and when m2 is 1, it is a naphthalene ring, but from the viewpoint of solvent solubility, it is preferable that m1 is a benzene ring with a value of 0. m3 is either 0 or 1. When m3 is 0, it is a benzene ring, and when m3 is 1, it is a naphthalene ring, but from the viewpoint of solvent solubility, it is preferable that m3 is a benzene ring with a value of 0.

[0188] In formula (Z-3), m4 is 0, 1, 2, 3, or 4. The more iodine atoms in the cation structure there are, the higher the absorption, especially for EUV. However, this also leads to poor solvent solubility and concerns about precipitation in the resist composition. Therefore, m4 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2.

[0189] In formula (Z-3), m5 is 0, 1, 2, 3, or 4. From the viewpoint of raw material procurement, m5 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2. m6 is 0, 1, 2, 3, 4, 5, or 6. From the viewpoint of raw material procurement, m6 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2. m7 is 0, 1, 2, 3, 4, 5, or 6. From the viewpoint of raw material procurement, m7 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2.

[0190] In formula (Z-3), m8 is 0, 1, or 2. From the viewpoint of raw material procurement, it is preferable that m8 is 0 or 1. m9 is 0, 1, or 2. From the viewpoint of raw material procurement, it is preferable that m9 is 0 or 1. m10 is 0, 1, or 2. From the viewpoint of raw material procurement, it is preferable that m10 is 0 or 1.

[0191] In formula (Z-3), m11 is either 0 or 1. When m11 is 0, it is a benzene ring, and when m11 is 1, it is a naphthalene ring, but from the viewpoint of solvent solubility, a benzene ring with m11 being 0 is preferred.

[0192] In formula (Z-3), m12 is 0, 1, 2, 3, or 4. The more iodine atoms in the cation structure there are, the higher the absorption, especially for EUV. However, this also leads to poor solvent solubility and concerns about precipitation in the resist composition. Therefore, m12 is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2.

[0193] In formula (Z-3), m13 is 0, 1, or 2. From the viewpoint of raw material procurement, it is preferable that m13 is 0 or 1. m14 is 0, 1, or 2. From the viewpoint of synthesis, it is preferable that m14 is 0 or 1.

[0194] However, when m1 is 0, 0 ≤ m6 + m9 ≤ 4, and when m1 is 1, 0 ≤ m6 + m9 ≤ 6. When m2 is 0, 0 ≤ m7 + m10 ≤ 4, and when m2 is 1, 0 ≤ m7 + m10 ≤ 6. When m3 is 0, 1 ≤ m4 + m5 + m8 + m14 ≤ 4, and when m3 is 1, 1 ≤ m4 + m5 + m8 + m14 ≤ 6. When m11 is 0, 0 ≤ m12 + m13 ≤ 4, and when m11 is 1, 0 ≤ m12 + m13 ≤ 6. Also, m4 + m12 ≥ 1.

[0195] In formula (Z-3), R F1 ~R F3 Each of these 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, trifluoromethyl, trifluoromethoxy, and trifluorothiomethoxy groups are preferred. When m5 is 2, 3, or 4, each R F1 They may be the same or different from each other. When m6 is 2, 3, 4, 5 or 6, each R F2 They may be the same or different from each other. When m7 is 2, 3, 4, 5 or 6, each R F3 They may be the same as or different from each other.

[0196] In formula (Z-3), R ct6 ~R ct9 This is a C1-C20 hydrocarbyl group which may contain halogen atoms other than iodine and fluorine atoms, a nitro group, a cyano group, a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, or a C1-C20 hydrocarbylthio group which may contain a heteroatom. The hydrocarbyl portion of the hydrocarbyl group, hydrocarbyloxy group, and hydrocarbylthio group may be saturated or unsaturated, and may be linear, branched, or cyclic. For example, in the explanation of formula (a1), R 1 and R 2Examples of hydrocarbyl groups represented by the above are similar to those exemplified. Furthermore, some or all of the hydrogen atoms in 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, and halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, and nitrogen atoms, and as a result, the group may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, lactone rings, sultone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0197] Also, when m8 is 2, the two R ct6 The two Rs may be identical or different from each other. ct6 These may bond with each other to form a ring with the carbon atom to which they are bonded. When m9 is 2, two R ct7 The two Rs may be identical or different from each other. ct7 These may bond with each other to form a ring with the carbon atom to which they are bonded. When m10 is 2, two R ct8 The two Rs may be identical or different from each other. ct8 These may bond with each other to form a ring with the carbon atoms to which they are bonded. When m13 is 2, two R ct9 The two Rs may be identical or different from each other. ct9These elements may bond with each other to form a ring with the carbon atoms to which they are bonded. Specific examples of the ring formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornane rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the ring may be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and some of the -CH2- in the ring may be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc. As a result, the ring may contain 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, sultone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0198] Furthermore, S in the sulfonium cation represented by formula (Z-3) + Aromatic rings that are directly bonded to each other are bonded to each other, forming S + They may form a ring together. Specific examples of the ring structure include those represented by the following formula. [ka]

[0199] In formula (Z-3), L A and L B These are, independently, a single bond, an ether bond, an ester bond, an amide bond, a sulfonic acid ester bond, a sulfonamide bond, a carbonate bond, or a carbamate bond. Of these, L A The bond is preferably a single bond, an ether bond, an ester bond, or a sulfonic acid ester bond, and more preferably an ester bond or a sulfonic acid ester bond. B The bond is preferably a single bond, an ether bond, or an ester bond, and more preferably a single bond.

[0200] In formula (Z-3), X LThis is a 1-40 carbon atom hydrocarbylene group which may contain single bonds or heteroatoms. The hydrocarbylene group may be linear, branched, or cyclic, and specific examples include an alkanediyl group, a cyclic saturated hydrocarbylene group, and an arylene group. Specific examples of the heteroatom include an oxygen atom, a nitrogen atom, and a sulfur atom.

[0201] X L Specific examples of C1-C40 hydrocarbylene groups that may contain heteroatoms represented by the formulas shown below are, but are not limited to, those listed below. In the formulas below, * represents L A and L B This represents a combination of two things. [ka]

[0202] [ka]

[0203] [ka]

[0204] [ka]

[0205] Of these, X L -0~X L -22 and X L -47~X L -61 is preferred.

[0206] The sulfonium cation represented by formula (Z-3) is preferably the one represented by formula (Z-3-1) below. [ka] (In the formula, m4~m10, m12~m14, R F1~R F3 , R ct6 ~R ct9 , L A , L B and X L (This is the same as above.)

[0207] The sulfonium cation represented by formula (Z-3-1) is preferably the one represented by formula (Z-3-2) below. [ka] (In the formula, m4~m10, R F1 ~R F3 and R ct6 ~R ct8 (This is the same as above.)

[0208] Specific examples of sulfonium cations represented by formula (Z-3) are listed below, but are not limited to these. In the formula below, Me represents a methyl group. [ka]

[0209] [ka]

[0210] [ka]

[0211] [ka]

[0212] [ka]

[0213] [ka]

[0214]

change

[0215]

change

[0216]

change

[0217]

change

[0218]

change

[0219]

change

[0220]

change

[0221]

change

[0222]

change

[0223]

change

[0224]

change

[0225]

change

[0226]

change

[0227]

change

[0228]

change

[0229]

change

[0230]

change

[0231]

change

[0232]

change

[0233]

change

[0234]

change

[0235] [ka]

[0236] Specific examples of the aforementioned photoacid generator include any combination of the anion and cation mentioned above.

[0237] Examples of methods for synthesizing the aforementioned photoacid generator include those described in Japanese Patent Publication No. 2010-155824 and Japanese Patent No. 7067271, but these manufacturing methods are merely examples, and the method for producing the photoacid generator in the chemically amplified resist composition of the present invention is not limited to these.

[0238] In the chemically amplified resist composition of the present invention, the content of (B) photoacid generator is preferably 0.1 to 40 parts by mass, and more preferably 0.5 to 20 parts by mass, per 80 parts by mass of (A) base polymer. When the amount of photoacid generator of component (B) is added within the above range, the resolution is good and there is no risk of foreign matter problems occurring after development or peeling of the resist film, so it is preferable. (B) photoacid generator may be used alone or in combination of two or more types.

[0239] [(C) Organic Solvents] The chemically amplified resist composition of the present invention may contain an organic solvent as component (C). The organic solvent (C) is not particularly limited as long as it is capable of dissolving the components described above and the components described later. 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; 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; 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 of these.

[0240] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, cyclohexanone, GBL, DAA, and mixed solvents thereof are preferred, as they exhibit particularly excellent solubility of the base polymer of component (A).

[0241] In the chemically amplified 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, per 80 parts by mass of (A) base polymer. (C) organic solvent may be used alone or as a mixture of two or more types.

[0242] [(D) Quencher] The chemical amplification resist composition of the present invention may contain a quencher as component (D). In the present invention, a quencher is a material that traps the strong acid generated from the photoacid generator in the chemical amplification resist composition, thereby preventing its diffusion to unexposed areas and forming a desired pattern. A strong acid means an acid that has sufficient acidity to cause a deprotection reaction of acid-unstable groups.

[0243] (D) Specific examples of quenchers include onium salts represented by the following formulas (2) or (3). [ka]

[0244] In formula (2), R q1 This is a hydrocarbyl group having 1 to 40 carbon atoms, which may contain a hydrogen atom or a heteroatom, but excludes those in which 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 This is a hydrocarbyl group having 1 to 40 carbon atoms, which may contain a hydrogen atom or a heteroatom.

[0245] R q1 Specifically, the C1-C40 hydrocarbyl groups represented by include C1-C40 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, and 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. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and some of the -CH2- groups of the hydrocarbyl group may be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, the group may contain 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, sultone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0246] R q2 Specifically, the hydrocarbyl group represented by R q1 In addition to the substituents exemplified as specific examples, other examples include fluorinated saturated hydrocarbyl groups such as trifluoromethyl and trifluoroethyl groups, and fluorinated aryl groups such as pentafluorophenyl and 4-trifluoromethylphenyl groups.

[0247] Specific examples of anions of onium salts represented by formula (2) are listed below, but are not limited to these. [ka]

[0248] [ka]

[0249] [ka]

[0250] [ka]

[0251] [ka]

[0252] Specific examples of anions of onium salts represented by formula (3) are listed below, but are not limited to these. [ka]

[0253] [ka]

[0254] [ka]

[0255] [ka]

[0256] [ka]

[0257] In equations (2) and (3), MQ +This is an onium cation. Examples of the onium cation include sulfonium cations, iodonium cations, ammonium cations, etc. Specific examples of the sulfonium cation include those exemplified as specific examples of sulfonium cations represented by formulas (Z-1) and (Z-3), 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 Japanese Patent No. 7491173, but are not limited to these. Specific examples of iodonium cations include those exemplified as specific examples of iodonium cations represented by formula (Z-2), but are not limited to these. A preferred specific example of the ammonium cation is the ammonium cation represented by the following formula (Z-4). [ka]

[0258] In formula (Z-4), R ct11 ~R ct14 Each of these is independently a hydrocarbyl group having 1 to 40 carbon atoms, which may contain heteroatoms. Also, R ct11 and R ct12 However, they may bond with each other to form a ring with the nitrogen atom to which they are bonded. Specific examples of the hydrocarbyl group include R in the explanation of formulas (Z-1) and (Z-2). ct1 ~R ct5 Examples of hydrocarbyl groups represented by the same formula as those exemplified above include those shown.

[0259] Specific examples of ammonium cations represented by formula (Z-4) are listed below, but are not limited to these. [ka]

[0260] Specific examples of onium salts represented by formula (2) or (3) include any combination of the anions and cations mentioned above. These onium salts can be easily prepared by ion exchange reactions using known organic chemical methods. For ion exchange reactions, refer to, for example, Japanese Patent Publication No. 2007-145797.

[0261] The onium salt represented by formula (2) or (3) acts as a quencher in the chemically amplified resist composition of the present invention. This is because each counteranion of the onium salt is a conjugate base of a weak acid. Here, a weak acid means one that exhibits an acidity that cannot deprotect the acid-unstable groups of the acid-unstable group-containing units 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 photoacid generator having a conjugate base of a strong acid, such as a sulfonic acid with fluorinated α-position, as a counteranion. That is, when an onium salt that generates a strong acid, such as a sulfonic acid with fluorinated α-position, is mixed with an onium salt that generates a weak acid, such as an unfluorinated sulfonic acid or carboxylic acid, when the strong acid generated from the photoacid generator by high-energy ray irradiation collides with the onium salt having an unreacted weak acid anion, the weak acid is released by salt exchange, and an onium salt having a strong acid anion is produced. In this process, strong acids are replaced by weaker acids with lower catalytic activity, so the acids appear to be deactivated, allowing for control of acid diffusion.

[0262] Furthermore, as the (D) quencher, an onium salt having a sulfonium cation and a phenoxide anion moiety in the same molecule as described in Japanese Patent Publication No. 6848776, an onium salt having a sulfonium cation and a carboxylate anion moiety in the same molecule as described in Japanese Patent Publication No. 6583136 and Japanese Patent Application Publication No. 2020-200311, and an onium salt having an iodonium cation and a carboxylate anion moiety in the same molecule as described in Japanese Patent Publication No. 6274755 can also be used.

[0263] Here, if the photoacid generator that produces a strong acid is an onium salt, as mentioned above, the strong acid produced by high-energy ray irradiation can be exchanged for a weak acid. On the other hand, it is thought that the weak acid produced by high-energy ray irradiation is unlikely to collide with the unreacted onium salt that produces the strong acid and undergo salt exchange. This is due to the phenomenon that onium cations are more likely to form ion pairs with the anions of stronger acids.

[0264] When the chemically amplified resist composition of the present invention contains an onium salt represented by formula (2) or (3) as a (D) quencher, its content is preferably 0.1 to 20 parts by mass, and more preferably 0.1 to 10 parts by mass, per 80 parts by mass of the (B) base polymer. The onium salt type quencher content is preferred when it is within the above range because it provides good resolution and does not significantly reduce sensitivity. The onium salt represented by formula (2) or (3) may be used alone or in combination of two or more types.

[0265] The chemically amplified resist composition of the present invention may contain a nitrogen-containing compound as (D) 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, particularly amine compounds having a hydroxyl group, ether bond, ester bond, lactone ring, cyano group, or sulfonic acid ester bond. Also included are compounds in which primary or secondary amines are protected with a carbamate group, as described in Japanese Patent Publication No. 3790649. Furthermore, amine compounds having an acid-unstable group bonded to a lactone ring, sultone ring, lactam ring, or sultam ring, as described in Japanese Patent Publication No. 7615989.

[0266] Furthermore, a sulfonium sulfonate salt having a nitrogen-containing substituent may be used as the nitrogen-containing compound. Such a compound functions as a quencher in the unexposed area and loses its quenching ability in the exposed area through neutralization with its own generated acid, functioning as a so-called photodecayable base. By using a photodecayable base, the contrast between the exposed and unexposed areas can be further enhanced. For example, Japanese Patent Publication No. 2009-109595 and Japanese Patent Publication No. 2012-46501 can be referenced as examples of photodecayable bases.

[0267] When the chemically amplified resist composition of the present invention contains a nitrogen-containing compound as (D) quencher, the content is preferably 0.001 to 12 parts by mass, and more preferably 0.01 to 8 parts by mass, per 80 parts by mass of the (A) base polymer. The nitrogen-containing compound may be used alone or in combination of two or more.

[0268] [(E) Other photoacid generators] The chemically amplified resist composition of the present invention may contain a photoacid generator other than component (B) (hereinafter also referred to as "other photoacid generator") as component (E). The other photoacid generator is not particularly limited as long as it is a compound that generates a strong acid upon irradiation with high-energy rays. Suitable other photoacid generators include those represented by the following formulas (4) or (5). [ka]

[0269] In formula (4), R 111 ~R 115 Each of these is independently a C1-C20 hydrocarbyl group which may contain a halogen atom or a heteroatom. 111 , R 112 and R 113 Any two of these may bond with each other to form a ring with the sulfur atom to which they are bonded. Specific examples of the hydrocarbyl group include R in the explanation of formulas (Z-1) and (Z-2). ct1 ~R ct5Examples of hydrocarbyl groups represented by the same formula as those exemplified above include those shown.

[0270] Specific examples of sulfonium salt cations represented by formula (4) include, but are not limited to, 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 Japanese Patent No. 7491173, and those exemplified as specific examples of sulfonium cations represented by formula (Z-3). Specific examples of iodonium salt cations represented by formula (5) include, but are not limited to, those described in paragraph

[0181] of Japanese Patent Publication No. 2024-259.

[0271] In equations (4) and (5), Xa - This is an anion of a strong acid. Examples of the strong acid anions include those represented by any of the following formulas (Xa-1) to (Xa-4). [ka]

[0272] In equation (Xa-1), R fa R is a hydrocarbyl group having 1 to 60 carbon atoms, which may contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (Xa-1-1) described later. fa1Examples of hydrocarbyl groups represented by the above are similar to those exemplified. Furthermore, 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, it may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0273] The anion represented by formula (Xa-1) is preferably the one represented by the following formula (Xa-1-1). [ka]

[0274] In equation (Xa-1-1), Q 1 and Q 2 Each of these is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbyl group having 1 to 6 carbon atoms, but to improve solvent solubility, it is preferable that at least one of them is a trifluoromethyl group. k is 0, 1, 2, 3, or 4, but it is particularly preferable that it is 1. R fa1 This is a hydrocarbyl group having 1 to 35 carbon atoms, which may contain heteroatoms. The heteroatoms are preferably oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms, etc., with oxygen atoms being more preferred. From the viewpoint of obtaining high resolution in fine pattern formation, the hydrocarbyl group having 6 to 30 carbon atoms is particularly preferred.

[0275] In equation (Xa-1-1), R fa1The C1-C40 hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include C1-C40 alkyl groups 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 eicosyl; cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norbornyl, norbornylmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl. Examples include cyclic saturated hydrocarbyl groups with 3 to 40 carbon atoms, such as the tyl group; unsaturated aliphatic hydrocarbyl groups with 2 to 40 carbon atoms, such as the 2-propenyl group and the 3-cyclohexenyl group; aryl groups with 6 to 40 carbon atoms, such as the phenyl group, the 1-naphthyl group, the 2-naphthyl group, and the 9-fluorenyl group; aralkyl groups with 7 to 40 carbon atoms, such as the benzyl group and the diphenylmethyl group; aromatic ring-containing polycyclic hydrocarbyl groups with 7 to 40 carbon atoms, such as the 9,10-ethano-9,10-dihydroanthryl group and the 6,13-ethano-6,13-dihydropentacenyl group; hydrocarbyl groups with 17 to 40 carbon atoms having a steroid skeleton; and groups obtained by combining these.

[0276] Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. Specific examples of hydrocarbyl groups containing heteroatoms include tetrahydrofuryl group, methoxymethyl group, ethoxymethyl group, methylthiomethyl group, acetamidomethyl group, trifluoroethyl group, (2-methoxyethoxy)methyl group, acetoxymethyl group, 2-carboxy-1-cyclohexyl group, 2-oxopropyl group, 4-oxo-1-adamantyl group, and 3-oxocyclohexyl group.

[0277] In equation (Xa-1-1), L a1 The bond can be a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, or a carbamate bond, but from a synthetic viewpoint, an ether bond or an ester bond is preferred, and an ester bond is even more preferred.

[0278] Specific examples of anions represented by formula (Xa-1) are listed below, but are not limited to these. Note that in the formula below, Q 1 This is the same as above, and Ac is an acetyl group. [ka]

[0279] [ka]

[0280] [ka]

[0281] [ka]

[0282] [ka]

[0283] [ka]

[0284] [ka]

[0285] [ka]

[0286] [ka]

[0287] [ka]

[0288] [ka]

[0289] [ka]

[0290] In equation (Xa-2), R fb1 and R fb2Each of these is a hydrocarbyl group having 1 to 40 carbon atoms, which may independently contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (Xa-1-1). fa1 Examples of hydrocarbyl groups represented by R include those similar to those exemplified. fb1 and R fb2 Preferably, R is a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. fb1 and R fb2 However, they bond to each other and the group to which they bond (-CF2-SO2-N - It may form a ring with -SO2-CF2-), in which case R fb1 and R fb2 The groups obtained by the bonding of these groups are preferably fluorinated ethylene groups or fluorinated propylene groups.

[0291] In equation (Xa-3), R fc1 , R fc2 and R fc3 Each of these is a hydrocarbyl group having 1 to 40 carbon atoms, which may independently contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (Xa-1-1). fa1 Examples of hydrocarbyl groups represented by R include those similar to those exemplified. fc1 , R fc2 and R fc3 Preferably, R is a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. fc1 and R fc2 However, they bond to each other and the group to which they bond (-CF2-SO2-C - It may form a ring with -SO2-CF2-), in which case R fc1 and R fc2 The groups obtained by the bonding of these groups are preferably fluorinated ethylene groups or fluorinated propylene groups.

[0292] In equation (Xa-4), R fdR is a hydrocarbyl group having 1 to 40 carbon atoms, which may contain heteroatoms. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (Xa-1-1). fa1 Examples of hydrocarbyl groups represented by the above are similar to those exemplified. Furthermore, 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, it may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0293] Specific examples of anions represented by formula (Xa-4) are listed below, but are not limited to these. [ka]

[0294] [ka]

[0295] As the non-nucleophilic counterions, the following can also be used: a fluorobenzenesulfonic acid anion bonded to an aromatic group containing an iodine atom, as described in Japanese Patent No. 6648726; an anion having a mechanism for decomposition by acid, as described in International Publication No. 2021 / 200056 and Japanese Patent Application Publication No. 2021-70692; an anion having a cyclic ether group, as described in Japanese Patent Application Publication No. 2018-180525 and Japanese Patent Application Publication No. 2021-35935; and an anion described in Japanese Patent Application Publication No. 2018-92159.

[0296] As the non-nucleophilic counterions, anions of bulky benzenesulfonic acid derivatives that do not contain fluorine atoms, as described in Japanese Patent Publication No. 2006-276759, Japanese Patent Publication No. 2015-117200, Japanese Patent Publication No. 2016-65016, Japanese Patent Publication No. 2019-202974, and Japanese Patent Publication No. 2024-104830, as well as benzenesulfonic acid anions and alkylsulfonic acid anions that do not contain fluorine atoms bonded to an aromatic group containing an iodine atom, as described in Japanese Patent No. 6645464. Furthermore, anions described in paragraphs

[0229] to

[0231] of Japanese Patent Publication No. 2024-77330 and paragraphs

[0033] to

[0093] of Japanese Patent Publication No. 2024-140135 can also be used.

[0297] As the non-nucleophilic counterion, other options include the bissulfonic acid anion described in Japanese Patent Publication No. 2015-206932, the sulfonamide or sulfonimide anion described in International Publication No. 2020 / 158366, which has a sulfonic acid on one end and a different sulfonamide or sulfonimide on the other, and the sulfonate anion described in Japanese Patent Publication No. 2015-24989.

[0298] Furthermore, as an additional photoacid generator for component (E), one represented by the following formula (6) is also preferred. [ka]

[0299] In formula (6), R 201 and R 202 Each of these is independently a hydrocarbyl group having 1 to 30 carbon atoms, which may contain heteroatoms. 203 This is a hydrocarbylene group having 1 to 30 carbon atoms, which may contain heteroatoms. Also, R 201 , R 202 and R 203 Any two of these may bond with each other to form a ring with the sulfur atom to which they are bonded.

[0300] R 201 and R202 The C1-C30 hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include C1-C30 alkyl groups 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, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, oxanorbornyl, and tricyclo[5.2.1.0 2,6 Examples 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, anthracenyl groups, and groups obtained by combining these. 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- groups of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, the material may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, lactone rings, sultone rings, carboxylic acid anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0301] R 203The hydrocarbylene group, represented by , having 1 to 30 carbon atoms, may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include alkane diyl groups with 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, heptadecane-1,17-diyl group, etc.; cyclop Examples include cyclic saturated hydrocarbylene groups having 3 to 30 carbon atoms, such as tananediyl group, cyclohexanediyl group, norbornanediyl group, and adamantanediyl group; and arylene groups such as phenylene group, methylphenylene group, ethylphenylene group, n-propylphenylene group, isopropylphenylene group, n-butylphenylene group, isobutylphenylene group, sec-butylphenylene group, tert-butylphenylene group, naphthylene group, methylnaphthylene group, ethylnaphthylene group, n-propylnaphthylene group, isopropylnaphthylene group, n-butylnaphthylene group, isobutylnaphthylene group, sec-butylnaphthylene group, and tert-butylnaphthylene group. Furthermore, some or all of the hydrogen atoms of the hydrocarbylene group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbylene group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain 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 sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. The heteroatom is preferably an oxygen atom.

[0302] In formula (6), L 11This is a 1-20 carbon atom hydrocarbylene group which may contain single bonds, ether bonds, or heteroatoms. The hydrocarbylene group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R 203 Examples of hydrocarbylene groups represented by the same formula as those exemplified are also available.

[0303] In formula (6), X a , X b , X c and X d Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group. However, X a , X b , X c and X d At least one of these is a fluorine atom or a trifluoromethyl group.

[0304] The photoacid generator represented by formula (6) is preferably the one represented by formula (6') below. [ka]

[0305] In formula (6'), L 11 This is the same as above. X e R is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. 301 , R 302 and R 303 Each of these is a hydrocarbyl group having 1 to 20 carbon atoms, which may each contain a hydrogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (Xa-1-1). fa1 Examples of hydrocarbyl groups represented by the formula are similar to those exemplified. p and q are independently 0, 1, 2, 3, 4, or 5, and r is 0, 1, 2, 3, or 4.

[0306] Specific examples of the photoacid generator represented by formula (6) include those similar to those exemplified as the photoacid generator represented by formula (2) in Japanese Patent Publication No. 2017-26980.

[0307] Among the other photoacid generators mentioned above, those containing anions represented by formula (Xa-1-1) or (Xa-4) are particularly preferred because they exhibit low acid diffusion and excellent solubility in solvents. Furthermore, those represented by formula (6') are particularly preferred because they exhibit extremely low acid diffusion.

[0308] If the chemically amplified resist composition of the present invention contains (E) other photoacid generators, the content thereof is preferably 0.1 to 40 parts by mass, and more preferably 0.5 to 20 parts by mass, per 80 parts by mass of the (A) base polymer. When the amount of photoacid generator added to component (E) is within the above range, the resolution is good and there is no risk of foreign matter problems occurring after development or peeling of the resist film, so it is preferable. (E) Other photoacid generators may be used alone or in combination of two or more types.

[0309] [(F) Surfactants] The chemically amplified resist composition of the present invention may further contain a surfactant as component (F). Preferably, the surfactant (F) 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 both water and an alkaline developer. Examples of such surfactants can be found in Japanese Patent Publication No. 2010-215608 and Japanese Patent Publication No. 2011-16746.

[0310] As surfactants that are insoluble or poorly soluble in water and alkaline developer, among the surfactants described in the above publication, FC-4430 (manufactured by 3M), Surflon® S-381 (manufactured by AGC Seimi Chemical Co., Ltd.), Orfin® E1004 (manufactured by Nisshin Chemical Industry 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. [ka]

[0311] Here, R, Rf, A, B, C, m, and n apply only to formula (surf-1), notwithstanding the preceding description. R is a divalent to tetravalent aliphatic group having 2 to 5 carbon atoms. Examples of such aliphatic groups include the divalent ethylene group, 1,4-butylene group, 1,2-propylene group, 2,2-dimethyl-1,3-propylene group, and 1,5-pentylene group, while examples of trivalent or tetravalent aliphatic groups are listed below. [ka] (In the formula, the dashed lines represent bonds, which are substructures derived from glycerol, trimethylolethane, trimethylolpropane, and pentaerythritol, respectively.)

[0312] Among these, the 1,4-butylene group and the 2,2-dimethyl-1,3-propylene group are preferred.

[0313] 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, and the sum of n and m is the valence of R, 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. Furthermore, the order of each constituent unit in formula (surf-1) is not specified, and they may be bonded in a block-like manner or randomly. For details on the production of partially fluorinated oxetane ring-opening polymer surfactants, please refer to U.S. Patent No. 5,650,483, etc.

[0314] Surfactants that are insoluble or sparingly soluble in water and soluble in alkaline developers have the function of reducing water penetration and leaching by orienting themselves on the surface of the resist film when a resist protective film is not used in ArF immersion lithography. Therefore, they are useful in suppressing the elution of water-soluble components from the resist film and reducing damage to the exposure equipment. Furthermore, they are useful because they become solubilized during alkaline aqueous solution development after exposure or post-exposure bake (PEB) and are less likely to become foreign substances that cause defects. Such surfactants are insoluble or sparingly soluble in water and soluble in alkaline developers, and are polymer-type surfactants, also called hydrophobic resins, with those that have particularly high water repellency and improve water lubricity being preferred.

[0315] Specific examples of such polymer-type surfactants include those containing at least one selected from the following repeating units: the repeating unit represented by formula (7A) (hereinafter also referred to as repeating unit 7A), the repeating unit represented by formula (7B) (hereinafter also referred to as repeating unit 7B), the repeating unit represented by formula (7C) (hereinafter also referred to as repeating unit 7C), the repeating unit represented by formula (7D) (hereinafter also referred to as repeating unit 7D), and the repeating unit represented by formula (7E) (hereinafter also referred to as repeating unit 7E). [ka]

[0316] In formulas (7A) to (7E), R B is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 R is -CH2-, -CH2CH2-, -O-, or two separated -H atoms. s1 Each of these is independently a hydrogen atom or a hydrocarbyl group having 1 to 10 carbon atoms. s2 This is a single bond, or a linear or branched hydrocarbylene group having 1 to 5 carbon atoms. s3 Each of these is independently a hydrogen atom, a hydrocarbyl group having 1 to 15 carbon atoms or a fluorinated hydrocarbyl group, or an acid-unstable group. s3If the group is a hydrocarbyl group or a fluorinated hydrocarbyl group, an ether bond or a carbonyl group may be interposed between the carbon-carbon bonds. s4 R is a (u+1) valent hydrocarbon group or fluorinated hydrocarbon group having 1 to 20 carbon atoms. u is 1, 2, or 3. s5 These are, independently, hydrogen atoms, or -C(=O)-OR sa It is a group represented by R. sa This is a fluorinated hydrocarbyl group having 1 to 20 carbon atoms. s6 This 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.

[0317] R s1 The C1-C10 hydrocarbyl group represented by is preferably a saturated hydrocarbyl group and may be linear, branched, or cyclic. Specific examples include C1-C10 alkyl groups 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 C3-C10 cyclic saturated hydrocarbyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, and norbornyl groups. Of these, those with C1-C6 are preferred.

[0318] R s2 The hydrocarbylene group represented by is preferably a saturated hydrocarbylene group and may be linear, branched, or cyclic. Specific examples include methylene, ethylene, propylene, butylene, and pentylene groups.

[0319] R s3 or R s6The hydrocarbyl group represented by may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include saturated hydrocarbyl groups, alkenyl groups, alkynyl groups, and other aliphatic unsaturated hydrocarbyl groups, but saturated hydrocarbyl groups are preferred. A specific example of the saturated hydrocarbyl group is R s1 In addition to the examples given as hydrocarbyl groups represented by , other examples include undecyl groups, dodecyl groups, tridecyl groups, tetradecyl groups, pentadecyl groups, etc. s3 or R s6 Specific examples of fluorinated hydrocarbyl groups represented by the formula include groups in which some or all of the hydrogen atoms bonded to the carbon atoms of the aforementioned hydrocarbyl group are replaced with fluorine atoms. As mentioned above, ether bonds or carbonyl groups may be interposed between these carbon-carbon bonds.

[0320] R s3 Specific examples of acid-unstable groups represented by the formulas (AL-3) to (AL-5) mentioned above include trialkylsilyl groups in which each alkyl group has 1 to 6 carbon atoms, and alkyl groups containing oxo groups with 4 to 20 carbon atoms.

[0321] R s4 The (u+1) valent hydrocarbon group or fluorinated hydrocarbon group represented by can be linear, branched, or cyclic. Specific examples include groups obtained by further removing u hydrogen atoms from the aforementioned hydrocarbyl group or fluorinated hydrocarbyl group.

[0322] R saThe fluorinated hydrocarbyl group represented by is preferably saturated and may be linear, branched, or cyclic. Specific examples include those in which some or all of the hydrogen atoms of the hydrocarbyl group are substituted with fluorine atoms, and specific examples of such include trifluoromethyl group, 2,2,2-trifluoroethyl group, 3,3,3-trifluoro-1-propyl group, 3,3,3-trifluoro-2-propyl group, 2,2,3,3-tetrafluoropropyl group, 1,1,1,3,3,3-hexafluoroisopropyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, 2,2,3,3,4,4,5,5-octafluoropentyl group, 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl group, 2-(perfluorobutyl)ethyl group, 2-(perfluorohexyl)ethyl group, 2-(perfluorooctyl)ethyl group, 2-(perfluorodecyl)ethyl group, etc.

[0323] Specific examples of repeating units 7A to 7E are shown below, but are not limited to these. Note that in the following formula, R B This is the same as described above. [ka]

[0324] [ka]

[0325] [ka]

[0326] [ka]

[0327] [ka]

[0328] [ka]

[0329] The polymer-type surfactant may further contain other repeating units besides repeating units 7A to 7E. Specific examples of other repeating units include repeating units obtained from methacrylic acid or α-trifluoromethylacrylic acid derivatives. The content of repeating units 7A to 7E in the polymer-type surfactant is preferably 20 mol% or more, more preferably 60 mol% or more, and even more preferably 100 mol% of the total repeating units.

[0330] The Mw of the polymer-type surfactant is preferably 1,000 to 500,000, and more preferably 3,000 to 100,000. The Mw / Mn ratio is preferably 1.0 to 2.0, and more preferably 1.0 to 1.6.

[0331] One method for synthesizing the polymer-type surfactant is to polymerize a monomer containing an unsaturated bond that provides at least one repeating unit selected from 7A to 7E, and optionally other repeating units, by heating it in an organic solvent with a radical initiator. Specific examples of organic solvents used during polymerization include toluene, benzene, THF, diethyl ether, and dioxane. Specific examples of polymerization initiators include AIBN, 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl-2,2-azobis(2-methylpropionate), benzoyl peroxide, and lauroyl peroxide. The reaction temperature is preferably 50 to 100°C. The reaction time is preferably 4 to 24 hours. The acid-unstable group may be used as is after being introduced into the monomer, or it may be protected or partially protected after polymerization.

[0332] When synthesizing the polymer-type 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% relative to the total number of moles of monomers to be polymerized.

[0333] When the chemically amplified resist composition of the present invention contains a surfactant (F), its content is preferably 0.1 to 50 parts by mass, and more preferably 0.5 to 10 parts by mass, per 80 parts by mass of the base polymer (A). If the content of surfactant (F) is 0.1 parts by mass or more, the receding contact angle between the resist film surface and water is sufficiently improved, and if it is 50 parts by mass or less, the dissolution rate of the resist film surface in the developer is small, and the height of the formed fine pattern is sufficiently maintained. Surfactants (F) may be used alone or in combination of two or more types.

[0334] [(G) Dissolution inhibitor] The chemically amplified resist composition of the present invention may further contain a dissolution inhibitor as component (G). When the chemically amplified resist composition of the present invention is of the positive type, by incorporating a dissolution inhibitor, the difference in dissolution rate between the exposed and unexposed areas can be further increased, thereby further improving the resolution.

[0335] Specific examples of the dissolution inhibitor include compounds having a molecular weight of preferably 100 to 1000, more preferably 150 to 800, and containing two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atoms of the phenolic hydroxyl groups are substituted with acid-unstable groups in a proportion of 0 to 100 mol% overall, or compounds containing a carboxyl group in the molecule, in which the hydrogen atoms of the carboxyl group are substituted with acid-unstable groups in an average proportion of 50 to 100 mol overall. Specifically, examples include compounds in which the hydrogen atoms of the hydroxyl group or carboxyl group of bisphenol A, trisphenol, phenolphthalein, cresol novolac, naphthalenecarboxylic acid, adamantanecarboxylic acid, and cholic acid are substituted with acid-unstable groups, and for example, those described in paragraphs

[0155] to

[0178] of Japanese Patent Application Publication No. 2008-122932.

[0336] If the chemically amplified resist composition of the present invention contains (G) a dissolution inhibitor, its content is preferably 0 to 50 parts by mass, and more preferably 5 to 40 parts by mass, per 80 parts by mass of (A) the base polymer. (G) The dissolution inhibitor may be used alone or in combination of two or more types.

[0337] [(H) Other components] The chemically amplified resist composition of the present invention may contain, as (H) other components, compounds that decompose with acid to generate acid (acid-generating compounds), organic acid derivatives, fluorine-substituted alcohols, water-repellency enhancers, etc. As the acid-generating compounds, compounds described in Japanese Patent Publication No. 2009-269953 or Japanese Patent Publication No. 2010-215608 can be referenced. When the acid-generating compounds are included, their content is preferably 0 to 5 parts by mass, and more preferably 0 to 3 parts by mass, per 80 parts by mass of the (A) base polymer. If the content is too high, it becomes difficult to control acid diffusion, which may lead to deterioration of resolution and pattern shape. As the organic acid derivatives and fluorine-substituted alcohols, compounds described in Japanese Patent Publication No. 2009-269953 or Japanese Patent Publication No. 2010-215608 can be referenced.

[0338] The water-repellent enhancer can be used in immersion lithography without a topcoat. Preferred water-repellent enhancers include polymers containing alkyl fluoride, polymers containing 1,1,1,3,3,3-hexafluoro-2-propanol residues of a specific structure, and those exemplified in Japanese Patent Publication No. 2007-297590 and Japanese Patent Publication No. 2008-111103 are more preferred. The water-repellent enhancer needs to be soluble in an alkaline developer or an organic solvent developer. The aforementioned water-repellent enhancer having a specific 1,1,1,3,3,3-hexafluoro-2-propanol residue exhibits good solubility in the developer. As a water-repellent enhancer, polymers containing repeating units including amino groups or amine salts are highly effective in preventing acid evaporation in the PEB and thus preventing poor hole pattern opening after development. If the chemically amplified resist composition of the present invention contains the water-repellency improving agent, its content is preferably 0 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass, per 80 parts by mass of the (A) base polymer.

[0339] [Pattern formation method] When the chemically amplified resist composition of the present invention is used in the manufacture of various integrated circuits, known lithography techniques can be applied. For example, a pattern formation method may include a step of forming a resist film on a substrate using the chemically amplified resist composition described above, a step of exposing the resist film with high-energy rays, and a step of developing the exposed resist film using a developer.

[0340] First, the chemically amplified resist composition of the present invention is applied to a substrate for integrated circuit manufacturing (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflective film, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, MoSi2, SiO2, etc.) by a suitable coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, or doctor coating, so that the coating film thickness is 0.01 to 2.0 μm. This is then pre-baked on a hot plate, preferably at 60 to 150°C for 10 seconds to 30 minutes, more preferably at 80 to 120°C for 30 seconds to 20 minutes, to form a resist film.

[0341] Next, the resist film is exposed using high-energy rays. Examples of high-energy rays include ultraviolet rays, far-ultraviolet rays, EB rays, EUV rays with wavelengths of 3 to 15 nm, X-rays, soft X-rays, excimer laser light, gamma rays, and synchrotron radiation. When using ultraviolet rays, far-ultraviolet rays, EUV rays, X-rays, soft X-rays, excimer laser light, gamma rays, or synchrotron radiation as the high-energy rays, the exposure amount is preferably 1 to 200 mJ / cm², either directly or using a mask to form the desired pattern. 2 To the extent, more preferably 10 to 100 mJ / cm² 2 Irradiate to a degree that results in the following: When using EB as the high-energy beam, the exposure dose is preferably 0.1 to 100 μC / cm². 2 To a degree, more preferably 0.5 to 50 μC / cm² 2 The pattern is drawn either directly or using a mask to form the desired pattern. The chemically amplified resist composition of the present invention is particularly suitable for fine patterning using high-energy rays, including ArF excimer laser light with a wavelength of 193 nm, KrF excimer laser light with a wavelength of 248 nm, EB, or EUV, X-rays, soft X-rays, gamma rays, or synchrotron radiation with wavelengths of 3 to 15 nm.

[0342] After exposure, PEB may be performed on a hot plate at a temperature of preferably 60-150°C for 10 seconds to 30 minutes, more preferably at 80-120°C for 30 seconds to 20 minutes.

[0343] After exposure or PEB, development is performed using a developer solution containing 0.1 to 10% by mass, preferably 2 to 5% by mass, of an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, or tetrabutylammonium hydroxide, for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, by conventional methods such as the dip method, puddle method, or spray method. The areas irradiated with light dissolve in the developer solution, while the areas not exposed do not dissolve, forming the desired positive-type pattern on the substrate.

[0344] Negative patterns can also be obtained using an organic solvent developer instead of the aforementioned alkaline aqueous solution. Specific examples of developers used in this case include 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, 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 pentenoate, methyl crotate, and ethyl crotate. Examples include methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, pentyl lactate, isopentyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenyl acetate, and 2-phenylethyl acetate. These organic solvents may be used individually or in mixtures of two or more.

[0345] Rinsing may be performed at the end of development. A solvent that mixes with the developer but does not dissolve the resist film is preferred as the rinsing solution. Preferred solvents include C3-C10 alcohols, C8-C12 ether compounds, C6-C12 alkanes, alkenes, alkynes, and aromatic solvents.

[0346] Specific examples of the C3-C10 alcohols include n-propyl alcohol, isopropyl alcohol, 1-butyl alcohol, 2-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, tert-pentyl alcohol, neopentyl alcohol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methyl-3-pentanol, cyclopentanol, 1-hexanol, 2-hexanol, and 3-hexanol. Examples include 2,3-dimethyl-2-butanol, 3,3-dimethyl-1-butanol, 3,3-dimethyl-2-butanol, 2-ethyl-1-butanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, 4-methyl-3-pentanol, cyclohexanol, 1-octanol, and others.

[0347] Specific examples of the ether compounds having 8 to 12 carbon atoms include di-n-butyl ether, diisobutyl ether, di-sec-butyl ether, di-n-pentyl ether, diisopentyl ether, di-sec-pentyl ether, di-tert-pentyl ether, and di-n-hexyl ether.

[0348] Specific examples of the C6-C12 alkanes include hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, and cyclononane. Specific examples of the C6-C12 alkenes include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, and cyclooctene. Specific examples of the C6-C12 alkynes include hexine, heptine, and octine.

[0349] Specific examples of the aforementioned aromatic solvents include toluene, xylene, ethylbenzene, isopropylbenzene, tert-butylbenzene, and mesitylene.

[0350] Rinsing can reduce the occurrence of deformation and defects in the resist pattern. However, rinsing is not always necessary, and omitting it can reduce the amount of solvent used.

[0351] The developed hole patterns and trench patterns can also be shrunk using thermal flow, RELACS, or DSA techniques. A shrinking agent is applied to the hole pattern, and crosslinking of the shrinking agent occurs on the surface of the resist film due to the diffusion of an acid catalyst from the resist film during baking, causing the shrinking agent to adhere to the side walls of the hole pattern. The baking temperature is preferably 70 to 180°C, more preferably 80 to 170°C, and the baking time is preferably 10 to 300 seconds, during which excess shrinking agent is removed and the hole pattern is reduced in size. [Examples]

[0352] The present invention will be specifically described below with reference to synthesis examples, examples, and comparative examples, but the present invention is not limited to the following examples.

[0353] [1] Synthesis of base polymers The monomers used in the synthesis of the base polymer are as follows: [ka]

[0354] [ka]

[0355] [ka]

[0356] [ka]

[0357] [ka]

[0358] [Synthesis Example 1-1] Synthesis of Polymer P-1 Under a nitrogen atmosphere, 53.1 g of monomer a1-1, 35.8 g of monomer b-1, 11.1 g of monomer c-1, 5.72 g of V-601 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 139 g of MEK were placed in a flask to prepare a monomer-polymerization initiator solution. 46 g of MEK was placed in another flask under a nitrogen atmosphere and heated to 80°C with stirring. The monomer-polymerization initiator solution was then added dropwise over 4 hours. After the addition was complete, the polymerization solution was kept at 80°C and stirred for 2 hours, then cooled to room temperature. The resulting polymerization solution was added dropwise to 3000 g of hexane with vigorous stirring, and the precipitated polymer was filtered off. The obtained polymer was washed twice with 600 g of hexane and then vacuum-dried at 50°C for 20 hours to obtain a white powdery polymer P-1 (yield 96.4 g, yield 96%). The Mw of polymer P-1 was 5800, and the Mw / Mn ratio was 1.51. Note that Mw is a polystyrene-converted value measured using GPC with THF as the solvent. [ka]

[0359] [Synthesis Examples 1-2 to 1-35, Comparative Synthesis Examples 1-1 to 1-22] Synthesis of polymers P-2 to P-35 and comparative polymers CP-1 to CP-22 The polymers shown in Tables 1 and 2 were prepared using the same method as in Synthesis Example 1-1, except that the types and mixing ratios of each monomer were changed. In Tables 1 and 2, the numbers in parentheses represent the introduction ratio (mol%) of each repeating unit.

[0360] [Table 1]

[0361] [Table 2]

[0362] [2] Synthesis of photoacid generators [Synthesis Example 2-1] Synthesis of photoacid generator PAG-1 [ka]

[0363] Under a nitrogen atmosphere, compound SM-1 (10.4 g), compound SM-2 (4.5 g), methylene chloride (50 g), and water (30 g) were added and stirred for 15 minutes. The organic layer was then separated, washed with water, and concentrated under reduced pressure. Methyl isobutyl ketone (50 g) was added to the concentrate and azeotropic dehydration was performed. The residue was further purified by silica gel column chromatography to obtain 11.5 g of the target product, PAG-1, as an oily substance (yield 94%).

[0364] MALDI TOF-MS: POSITIVE M + 335(C 18 H 11 F4S + equivalent) NEGATIVE M - 891(C 26 H 16 F2I3O7S - equivalent)

[0365] [Synthesis Examples 2-2 to 2-9] Synthesis of PAG-2 to PAG-9 Using corresponding raw materials and known organic synthesis reactions, photoacid generators PAG-2 to PAG-9, represented by the following formulas, were synthesized. [ka]

[0366] [ka]

[0367] [ka]

[0368] [Comparative Synthesis Examples 2-1~2-6] Synthesis of cPAG-2~cPAG-6 Using corresponding raw materials and known organic synthesis reactions, comparative photoacid generators cPAG-1 to cPAG-6, represented by the following formulas, were synthesized. [ka]

[0369] [3] Preparation of resist composition [Examples 1-1 to 1-43, Comparative Examples 1-1 to 1-39] Chemical amplification resist compositions (R-1 to R-43, CR-1 to CR-39) were prepared by dissolving predetermined components selected from the base polymers (P-1 to P-35) of the present invention, comparative base polymers (CP-1 to CP-22), photoacid generators (PAG-1 to PAG-9), comparative photoacid generators (cPAG-1 to cPAG-5), other photoacid generators (PAG-Z), and quenchers (Q-1 to Q-4) in a solvent containing 0.01% by mass of FC-4430 manufactured by 3M as a surfactant, in the compositions shown in Tables 3 to 6 below, and filtering the solution through a 0.2 μm Teflon® type filter.

[0370] [Table 3]

[0371] [Table 4]

[0372] [Table 5]

[0373] [Table 6]

[0374] In Tables 3-6, the solvents, quenchers (Q-1-Q-4), and other photoacid generators (PAG-Z) are as follows: • Solvent: PGMEA (Propylene glycol monomethyl ether acetate) EL (Ethyl Lactate) DAA (Diacetone Alcohol)

[0375] • Quencher: Q-1~Q-4 [ka]

[0376] Other photoacid generators: PAG-Z [ka]

[0377] [4] EUV lithography evaluation (1) [Examples 3-1 to 3-43, Comparative Examples 3-1 to 3-39] Each of the chemically amplified resist compositions (R-1 to R-43, CR-1 to CR-39) shown in Tables 3 to 6 was spin-coated onto a Si substrate on which a silicon-containing spin-on hard mask SHB-A940 (silicon content 43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. had been formed to a thickness of 20 nm. A resist film with a thickness of 50 nm was then fabricated by pre-baking at 100°C for 60 seconds using a hot plate. The resist film was then exposed to an LS pattern with a wafer dimension of 18 nm and a pitch of 36 nm using an ASML EUV scanner NXE3300 (NA 0.33, σ 0.9 / 0.6, dipole illumination), with exposure dose and focus varied (exposure dose pitch: 1 mJ / cm²). 2 The process was carried out while adjusting the focus pitch (0.020 μm), and after exposure, PEB was performed for 60 seconds at the temperatures shown in Tables 7 and 8. Then, paddle development was performed for 30 seconds with a 2.38 mass% TMAH aqueous solution, rinsed with a surfactant-containing rinse material, and spin-dried to obtain a positive type pattern. The obtained LS patterns were observed using a Hitachi High-Technologies Corporation measuring SEM (CG6300), and the sensitivity, EL, LWR, DOF, and tilt limit were evaluated according to the method described below. The results are shown in Tables 7 and 8.

[0378] [Sensitivity evaluation] The optimal exposure dose Eop(mJ / cm²) for obtaining an LS pattern with a line width of 18nm and a pitch of 36nm is obtained. 2 The value of ) was calculated and defined as the sensitivity. The smaller this value, the higher the sensitivity.

[0379] [EL rating] The exposure amount formed within ±10% (16.2 to 19.8 nm) of the 18 nm space width in the aforementioned LS pattern was used to calculate the EL (unit: %) using the following formula. A larger value indicates better performance. EL(%) = (|E1-E2| / Eop) × 100 E1: Optimal exposure amount to give an LS pattern with a line width of 16.2 nm and a pitch of 36 nm. E2: Optimal exposure amount to give an LS pattern with a line width of 19.8 nm and a pitch of 36 nm. Eop: Optimal exposure amount to give an LS pattern with a line width of 18nm and a pitch of 36nm.

[0380] [LWR rating] The LS pattern obtained by irradiating with Eop was measured at 10 points along the longitudinal direction of the line, and the LWR was calculated as three times the standard deviation (σ) (3σ) from these results. The smaller this value, the less roughness and the more uniform the line width pattern obtained.

[0381] [DOF rating] To evaluate the depth of focus, the focus range formed within ±10% of the 18nm dimension (16.2 to 19.8nm) in the aforementioned LS pattern was determined. A larger value indicates a wider depth of focus.

[0382] [Evaluation of the limit of line pattern collapse] The line dimensions for each exposure amount at the optimal focus of the aforementioned LS pattern were measured at 10 points along the longitudinal direction. The thinnest line dimension obtained without collapse was defined as the collapse limit dimension. The smaller this value, the better the collapse limit.

[0383] [Development defect evaluation] The LS pattern with a line width of 18 nm and a pitch of 36 nm, formed with the aforementioned optimal exposure, is then inspected using a KLA2360 (product name) defect inspection device manufactured by KLA-Tencor. The pixel size of the defect inspection device is set to 0.16 μm and the threshold to 20. Defects (number of defects / cm²) are extracted from the differences resulting from the superposition of the comparison image and the pattern at the pixel level. 2 ) detects the number of defects per unit area (defects / cm²). 2 The number of development defects per unit area (units / cm²) was calculated. Subsequently, a defect review was conducted to classify and extract development defects from all defects, and the number of development defects per unit area (units / cm²) was calculated. 2 The performance index (%) was calculated. Values ​​less than 0.5 were classified as A, values ​​between 0.5 and 1.0 as B, values ​​between 1.0 and 5.0 as C, and values ​​of 5.0 or higher as D. A smaller value indicates better performance.

[0384] [Table 7]

[0385] [Table 8]

[0386] The results shown in Tables 7 and 8 indicate that the chemically amplified resist composition using the polymer of the present invention exhibits good sensitivity and excellent EL, LWR, and DOF. Furthermore, it was confirmed that the tilt limit value is small, and that the pattern is resistant to tilting even in fine pattern formation. Development defects were also suppressed. Therefore, the chemically amplified resist composition of the present invention is suitable as a material for EUV lithography.

[0387] [5] EUV Lithography Evaluation (2) [Examples 3-1 to 3-43, Comparative Examples 3-1 to 3-39] Each chemically amplified resist composition (R-1 to R-43, CR-1 to CR-39) shown in Tables 3 and 4 was spin-coated onto a Si substrate on which a silicon-containing spin-on hard mask SHB-A940 (silicon content 43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. had been formed to a thickness of 20 nm. The resist film was then pre-baked at 105°C for 60 seconds using a hot plate to produce a resist film with a thickness of 50 nm. This was then exposed using an ASML EUV scanner NXE3400 (NA 0.33, σ 0.9 / 0.6, quadruple pole illumination, wafer-mounted dimensions of 46 nm pitch, +20% bias hole pattern mask), and PEB was performed for 60 seconds at the temperatures listed in Tables 9 and 10 using a hot plate. Development was then performed with a 2.38% by mass TMAH aqueous solution for 30 seconds to form a hole pattern with dimensions of 23 nm. Using a Hitachi High-Technologies Corporation length-measuring SEM (CG6300), the exposure amount when a hole dimension of 23 nm was formed was measured and defined as the sensitivity. The dimensions of 50 holes at this point were also measured, and the CDU was defined as three times the standard deviation (σ) calculated from these results (3σ). The results are shown in Tables 9 and 10.

[0388] [Table 9]

[0389] [Table 10]

[0390] The results shown in Tables 9 and 10 confirm that the chemically amplified resist composition of the present invention exhibits good sensitivity and excellent CDU.

[0391] [6] Dry etching resistance evaluation [Examples 4-1 to 4-35, Comparative Examples 4-1 to 4-22] Two g each of the polymers shown in Tables 1 and 2 (polymers P-1 to P-35, comparative polymers CP-1 to CP-22) was dissolved in 10 g of cyclohexanone, filtered through a 0.2 μm size filter, and the resulting polymer solution was spin-coated onto a Si substrate to a thickness of 300 nm. The films were then evaluated under the following conditions. Etching test with CHF3 / CF4 gas: The difference in polymer film thickness before and after etching was determined using the TE-8500P dry etching system manufactured by Tokyo Electron Ltd. The etching conditions are as follows: Chamber pressure 40 Pa RF Power 1000W Gap 9mm CHF3 gas flow rate: 30 mL / min CF4 gas flow rate: 30 mL / min Ar gas flow rate: 100 mL / min Time 60sec This evaluation indicates that materials with less film thickness variation, i.e., those with less reduction in film thickness, have higher etching resistance. The results of the dry etching resistance are shown in Tables 11 and 12.

[0392] [Table 11]

[0393] [Table 12]

[0394] The results shown in Tables 11 and 12 confirm that the polymer of the present invention has excellent dry etching resistance to CHF3 / CF4 gases.

Claims

1. (A) A polymer containing repeating units represented by the following formula (a1), and not containing repeating units that generate acid upon exposure. (B) A photoacid generator containing an iodine atom or a fluoroalkanesulfonic acid anion having an aromatic ring structure substituted with an iodine atom and a bromine atom, and (C) Organic solvents A chemically amplified resist composition containing the following: 【Chemistry 1】 (In the formula, a1 is 0 or 1. When a1 is 0, a2 is 0, 1, 2 or 3, and when a1 is 1, a2 is 0, 1, 2, 3, 4 or 5.) R A These are a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. X 1 The bonds are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-. The asterisk (*) represents a bond with a carbon atom in the main chain. X 2 This refers to a single bond, an aliphatic hydrocarbylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a group obtained by combining these. X 3 and X 4 Each of these is independently either an oxygen atom or a sulfur atom. However, X 2 and X 4 It is bonded to the carbon atom adjacent to the aromatic ring. R 1 and R 2 are each independently a hydrocarbyl group having 1 to 20 carbon atoms which may contain a hydrogen atom or a heteroatom. Also, R 1 and R 2 may be bonded to each other to form a ring together with the carbon atom to which they are bonded. R 3 This may include halogen atoms, hydroxyl groups, cyano groups, nitro groups, pentafluorosulfanyl groups, C1-C20 hydrocarbyl groups which may contain heteroatoms, C1-C20 hydrocarbyloxy groups which may contain heteroatoms, C2-C20 hydrocarbyloxycarbonyl groups which may contain heteroatoms, C1-C20 hydrocarbylthio groups which may contain heteroatoms, or -N(R) 3A )(R 3B ) is R 3A and R 3B Each of these is independently a hydrogen atom or a hydrocarbyl group having 1 to 6 carbon atoms. When a2 is 2 or more, each R 3 They may be the same or different from each other, and there may be multiple R 3 These atoms may bond with each other to form a ring together with the carbon atoms of the aromatic ring to which they are bonded.

2. X 3 and X 4 The chemically amplified resist composition according to claim 1, wherein both are oxygen atoms.

3. X 2 The chemically amplified resist composition according to claim 1, wherein the carbonyl group is a carbonyl group.

4. The chemically amplified resist composition according to claim 1, wherein the photoacid generator is represented by the following formula (1). 【Chemistry 2】 (In the equation, x is 1, 2, or 3. Y is 1, 2, 3, 4, or 5.) z is 0, 1, 2, or 3, where 1 ≤ y + z ≤ 5. X BI When y is 1, it is an iodine atom, and when y is 2, 3, 4, or 5, it is an iodine atom or a bromine atom, but at least one is an iodine atom. L 1 This is a single bond, ether bond, ester bond, sulfonic acid ester bond, sulfonamide bond, amide bond, carbonate bond, carbamate bond, or a saturated hydrocarbylene group having 1 to 6 carbon atoms, wherein the hydrocarbylene group is -CH 2 - may be partially substituted with an ether bond, ester bond, sulfonic acid ester bond, sulfonamide bond, amide bond, carbonate bond, or carbamate bond. L 2 When x is 1, it is a C1-C20 hydrocarbylene group which may contain a single bond or a heteroatom, and when x is 2 or 3, it is a C1-C20 (x+1) valent hydrocarbon group which may contain a heteroatom. L 3 These are single bonds, ether bonds, ester bonds, sulfonic acid ester bonds, carbonate bonds, or carbamate bonds. R 101 This includes a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a pentafluorosulfanyl group, a C1-C20 hydrocarbyl group, a C1-C20 hydrocarbyloxy group, a C1-C20 hydrocarbylthio group, a C2-C20 hydrocarbylcarbonyl group, a C2-C20 hydrocarbyloxycarbonyl group, a C2-C20 hydrocarbylcarbonyloxy group, a C1-C20 hydrocarbylsulfonyloxy group, and -N(R 101A )(R 101B ), -N(R 101C )-C(=O)-R 101D or -N(R 101C )-C(=O)-O-R 101D The hydrocarbyl group, hydrocarbyloxy group, hydrocarbylthio group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may contain at least one selected from fluorine, chlorine, bromine, iodine, hydroxyl, amino, ester, and ether bonds. 101A and R 101B Each of these is independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. 101C R is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may also contain 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. 101D This 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 also contain 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. Rf 1 ~Rf 4 Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is either a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 (These may combine to form a carbonyl group.) Z + This is an onium cation.

5. Z + The chemically amplified resist composition according to claim 1, wherein the sulfonium cation represented by the following formula (Z-1) or the iodonium cation represented by the following formula (Z-2). 【Transformation 3】 (In the formula, R ct1 ~R ct5 Each of these is independently a hydrocarbyl group having 1 to 30 carbon atoms, which may contain a halogen atom or a heteroatom. Also, R ct1 and R ct2 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded.

6. Z + The onium salt according to claim 1, wherein the sulfonium cation is represented by the following formula (Z-3). 【Chemistry 4】 (In the formula, m1 is 0 or 1. m2 is 0 or 1. m3 is 0 or 1. m4 is 0, 1, 2, 3 or 4. m5 is 0, 1, 2, 3 or 4. m6 is 0, 1, 2, 3, 4, 5 or 6. m7 is 0, 1, 2, 3, 4, 5 or 6. m8 is 0, 1 or 2. m9 is 0, 1 or 2. m10 is 0, 1 or 2. m11 is 0 or 1. m12 is 0, 1, 2, 3 or 4. m13 is 0, 1 or 2. m14 is 0, It is either 1 or 2. However, when m1 is 0, 0 ≤ m6 + m9 ≤ 4, and when m1 is 1, 0 ≤ m6 + m9 ≤ 6. When m2 is 0, 0 ≤ m7 + m10 ≤ 4, and when m2 is 1, 0 ≤ m7 + m10 ≤ 6. When m3 is 0, 1 ≤ m4 + m5 + m8 + m14 ≤ 4, and when m3 is 1, 1 ≤ m4 + m5 + m8 + m14 ≤ 6. When m11 is 0, 0 ≤ m12 + m13 ≤ 4, and when m11 is 1, 0 ≤ m12 + m13 ≤ 6. Also, m4 + m12 ≥ 1. R F1 ~R F3 Each of these 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. When m5 is 2, 3, or 4, each R F1 They may be the same as or different from each other. When m6 is 2, 3, 4, 5 or 6, each R F2 They may be the same as or different from each other. When m7 is 2, 3, 4, 5 or 6, each R F3 They may be the same as or different from each other. R ct6 ~R ct9 This is a C1-C20 hydrocarbyl group which may contain halogen atoms other than iodine and fluorine atoms, a nitro group, a cyano group, a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, or a C1-C20 hydrocarbylthio group which may contain a heteroatom. When m8 is 2, two R ct6 The two Rs may be the same or different from each other. ct6 These may bond with each other to form a ring with the carbon atoms to which they are bonded. When m9 is 2, two R ct7 The two Rs may be the same or different from each other. ct7 These may bond with each other to form a ring with the carbon atoms to which they are bonded. When m10 is 2, two R ct8 The two Rs may be the same or different from each other. ct8 These may bond with each other to form a ring with the carbon atoms to which they are bonded. When m13 is 2, two R ct9 The two Rs may be the same or different from each other. ct9 These atoms may bond with each other to form a ring with the carbon atoms to which they are bonded. Furthermore, S in sulfonium cations + Aromatic rings that are directly bonded to each other are bonded to each other and form S + They may form a ring together. L A and L B These are, independently, a single bond, an ether bond, an ester bond, an amide bond, a sulfonic acid ester bond, a sulfonamide bond, a carbonate bond, or a carbamate bond. X L This is a hydrocarbylene group having 1 to 40 carbon atoms, which may contain single bonds or heteroatoms.

7. The chemically amplified resist composition according to claim 1, wherein the polymer further comprises at least one selected from repeating units represented by the following formula (a2) and repeating units represented by the following formula (a3). 【Transformation 5】 (In the formula, R A These are, independently, a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. X 5 This refers to a single bond, a phenylene group, a naphthylene group, or *-C(=O)-O-X 51 - 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 which may contain a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms which may contain a fluorine atom, or a halogen atom. 51 This is a saturated hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. X 6 These are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-. * represents a bond with a carbon atom in the main chain. R 11 This is a halogen atom, a cyano group, a hydroxyl group, a nitro group, a pentafluorosulfanyl group, a C1-C20 hydrocarbyl group which may contain a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyl group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or a C2-C20 hydrocarbyloxycarbonyl group which may contain a heteroatom. When b1 is 2, 3, or 4, each R 11 They may be the same as or different from each other. AL 1 and AL 2 These are, independently, acid-unstable groups. b1 is 0, 1, 2, 3, or 4.

8. The chemically amplified resist composition according to claim 1, wherein the polymer further comprises repeating units represented by the following formula (b). 【Transformation 6】 (In the formula, R A These are a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Y 1 The bonds are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-. The asterisk (*) represents a bond with a carbon atom in the main chain. R 21 This is a halogen atom, a carboxyl group, a nitro group, a cyano group, a pentafluorosulfanil group, a C1-C20 hydrocarbyl group which may contain a heteroatom, a C1-C20 hydrocarbyloxy group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyl group which may contain a heteroatom, a C2-C20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or a C2-C20 hydrocarbyloxycarbonyl group which may contain a heteroatom. When c2 is 2, 3, or 4, each R 21 They may be the same as or different from each other. c1 is 1, 2, 3, or 4. c2 is 0, 1, 2, 3, or 4, where 1 ≤ c1 + c2 ≤ 5.

9. The chemically amplified resist composition according to claim 1, wherein the polymer further comprises repeating units represented by the following formula (c). 【Transformation 7】 (In the formula, R A These are a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z 1 This consists of a single bond, a phenylene group, a naphthylene group, and *-C(=O)-O-Z. 11 - or * - C(=O) - N(H) - Z 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 which may contain a fluorine atom, a saturated hydrocarbyloxy group having 1 to 10 carbon atoms which may contain a fluorine atom, or a halogen atom. * represents a bond with a carbon atom of the main chain. Z 11 This is a saturated hydrocarbylene group, a phenylene group, or a naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbylene group may contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. R 31 This is a group having 1 to 20 carbon atoms that includes 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 sultone ring, and a carboxylic acid anhydride (-C(=O)-O-C(=O)-).

10. Furthermore, the chemically amplified resist composition according to claim 1, further comprising (D) a quencher.

11. Furthermore, the chemically amplified resist composition according to claim 1, further comprising (E) other acid generators.

12. Furthermore, the chemically amplified resist composition according to claim 1, further comprising (F) a surfactant.

13. A pattern forming method comprising the steps of: forming a resist film on a substrate using a chemically amplified resist composition according to any one of claims 1 to 12; exposing the resist film with a high-energy beam; and developing the exposed resist film using a developer.

14. The pattern forming method according to claim 13, wherein the high-energy beam is ArF excimer laser light with a wavelength of 193 nm or KrF excimer laser light with a wavelength of 248 nm, an electron beam or extreme ultraviolet light with a wavelength of 3 to 15 nm.

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