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

Abstract

The invention relates to a sulfonium salt, a chemically amplified positive resist composition and a resist pattern forming method. The present invention addresses the problem of providing: a chemically amplified positive resist composition having excellent solvent solubility and excellent lithography performance such as resolution, LER, and pattern shape in optical lithography using high-energy rays; and a pattern forming method using the chemically amplified positive resist composition. The sulfonium salt is represented by the following formula (A).

Description

Technical Field

[0001] This invention relates to matte salts, chemically amplified positive resist compositions, and methods for forming resist patterns. Background Technology

[0002] In recent years, the increasing integration of integrated circuits has led to a demand for finer pattern formation. Pattern processing below 0.2 μm primarily utilizes chemically amplified resist compositions using acid as a catalyst. Exposure sources can include high-energy rays such as ultraviolet light, far-ultraviolet light, and electron beams (EB). EB lithography, in particular, is used as an ultra-fine processing technique and is indispensable for the fabrication of blank photomasks in semiconductor manufacturing. Such optical lithography uses resist compositions that include positive types (dissolving the exposed area to form the pattern) and negative types (residual exposed area to form the pattern). The choice of resist composition depends on the desired resist pattern shape and is easy to implement.

[0003] Generally, EB (Edge Electrode) lithography does not use a mask. For positive patterns, a method is used where a fine-area EB is sequentially irradiated onto areas excluding the desired resist film residue. For negative patterns, the area where the resist film residue is to be retained is irradiated sequentially. This is a sweeping operation across the entire finely segmented area of ​​the processing surface, thus taking longer than a single exposure using a photomask. To avoid reducing throughput, the resist film must have high sensitivity. Furthermore, the longer lithography time makes it easier for differences to arise between the initial and later lithographic areas; the stability of the exposed areas in a vacuum over time is an important performance requirement. In addition, in the particularly important application of blank photomask processing, surface materials such as chromium compound films (e.g., chromium oxide deposited on the photomask substrate) can easily affect the pattern shape of the chemically amplified resist film. Maintaining high resolution and the etched shape, and keeping the resist film pattern outline rectangular regardless of the substrate type, is also an important performance requirement.

[0004] The sensitivity and pattern profile control of the aforementioned photoresist films have been improved through various methods, including the selection and combination of materials used in the photoresist composition and processing conditions. One such improvement addresses the issue of acid diffusion, which significantly affects the resolution of chemically amplified photoresist films. Photomask processing requires that the shape of the resulting photoresist pattern not change depending on the time up to post-exposure heating (PEB), but a major cause of time-dependent changes is acid diffusion caused by exposure. This acid diffusion problem is not limited to photomask processing; it also significantly affects sensitivity and resolution in general photoresist compositions, and therefore has been extensively explored.

[0005] Patent documents 1 and 2 describe examples of suppressing acid diffusion and reducing roughness by increasing the volume of the acid generated from the acid generator. However, the suppression of acid diffusion in such acid generators is still insufficient, so it is desirable to develop acid generators with smaller diffusion.

[0006] Furthermore, Patent Documents 3-6 describe examples of controlling acid diffusion by bonding sulfonic acid generated during exposure to the resin used in the resist composition. This method of introducing repeating units that generate acid during exposure into the base polymer to suppress acid diffusion is effective when obtaining patterns with low line edge roughness (LER). However, depending on the structure and introduction rate of these repeating units, there are cases where the base polymer containing the repeating units that generate acid during exposure may experience problems with its solubility in organic solvents.

[0007] Furthermore, polymers containing a large amount of aromatic backbones with acidic side chains, such as polyhydroxystyrene, have been used as resist compositions for KrF lithography. However, they exhibit significant absorption for light around 200 nm and are therefore not used as resist compositions for ArF lithography. Nevertheless, resist compositions for EB lithography and extreme ultraviolet (EUV) lithography, which are powerful techniques for forming patterns with smaller processing limits than ArF lithography, are important materials from the viewpoint of achieving high etch resistance.

[0008] For the base polymers of resist compositions for positive EB lithography and EUV lithography, the main materials used are those that utilize acid generated from a photoacid generator by irradiation with high-energy rays as a catalyst to deprotect the acidic functional groups (acid-decomposing protecting groups) of the phenolic side chains of the base polymer, making them soluble in alkaline developing solutions. The aforementioned acid-insecure groups mainly include tert-alkyl, tert-butoxycarbonyl, and acetal groups. While using protecting groups with low activation energy, such as acetal groups, for deprotection can yield highly sensitive resist films, insufficient suppression of acid diffusion can lead to deprotection reactions in unexposed areas of the resist film, resulting in LER degradation and reduced dimensional uniformity of pattern linewidth (CDU).

[0009] With the recent advancements in the miniaturization of resist patterns, controlling the diffusion of acids generated by photoacid generators has become crucial, leading to the development of various acid diffusion control agents (quenchers). Examples of such quenchers include known amine compounds, as well as onium salt-type quenchers such as sulfonium salts and ferrophosphate salts. Patent Document 7 describes onium salts of carboxylic acids with nitrogen-containing heterocyclic structures such as indole. Furthermore, Patent Documents 8-10 propose quenchers derived from betaine-type onium salts that have phenylene oxide anions and carboxylate anions bonded intramolecularly to the same molecules as sulfonium and ferrophosphate cations. While these quenchers have demonstrated some performance improvement, satisfactory results have not yet been achieved. To meet future miniaturization requirements, the development of resist materials with excellent photolithographic properties and pattern shapes is also anticipated.

[0010] Existing technical documents

[0011] Patent documents

[0012] [Patent Document 1] Japanese Patent Application Publication No. 2009-053518

[0013] [Patent Document 2] Japanese Patent Application Publication No. 2010-100604

[0014] [Patent Document 3] Japanese Patent No. 4425776

[0015] [Patent Document 4] Japanese Patent No. 5201363

[0016] [Patent Document 5] Japanese Patent No. 5231357

[0017] [Patent Document 6] International Publication No. 2008 / 081832

[0018] [Patent Document 7] Japanese Patent No. 6515831

[0019] [Patent Document 8] Japanese Patent No. 6848776

[0020] [Patent Document 9] Japanese Patent No. 6583136

[0021] [Patent Document 10] Japanese Patent No. 6246480 Summary of the Invention

[0022] [The problem that the invention aims to solve]

[0023] In recent years, there has been a demand for resist compositions that not only have excellent line spacing (LS), isolated lines (IL), and isolated spacing (IS), but also excellent hole pattern shape and excellent shape after pattern formation.

[0024] The present invention was made in view of the foregoing circumstances, and aims to provide a chemically amplified positive resist composition that exhibits good solvent solubility and excellent lithographic performance, such as resolution, LER, and pattern shape, especially in optical lithography using high-energy rays such as KrF excimer lasers, ArF excimer lasers, EB, and EUV, and a method for pattern formation using the chemically amplified resist composition.

[0025] [Methods for solving the problem]

[0026] After repeated and in-depth research in order to achieve the aforementioned objectives, the inventors of this application discovered that, in terms of quenching agents, by using betaine-type sulfonate salts having 6 to 18 carbon chain alkyl groups or 4 to 18 carbon chain fluorinated alkyl groups and having sulfonate cations and carboxylate anions within the same molecule as the composition of chemically amplified positive resists, the solvent solubility is excellent, especially in EB lithography and EUV lithography, and the lithographic performance such as resolution, LER, and pattern shape is excellent, thus completing the present invention.

[0027] That is, the present invention provides the following matte salt, chemically amplified positive resist composition and resist patterning method.

[0028] 1. A sulfonium salt, represented by the following formula (A).

[0029] [Chemistry 1]

[0030]

[0031] In the formula, n1 is 0 or 1. n2 is 0, 1, 2, 3 or 4. n3 is 0 or 1. n4 is 0, 1, 2, 3 or 4.

[0032] L A It can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond.

[0033] R alk It is an alkyl group having 6 to 18 carbon atoms or a fluorinated alkyl group having 4 to 18 carbon atoms. R alk When it is an alkyl group having 6 to 18 carbon atoms, the alkyl group has at least one straight-chain structure with 6 or more carbon atoms. R alk When the fluorinated alkyl group has 4 to 18 carbon atoms, it has at least two groups selected from -CF2- and -CF3. Furthermore, a portion of the -CH2- group of the aforementioned alkyl and fluorinated alkyl groups may be substituted with an ether bond or a carbonyl group, and the aforementioned alkyl and fluorinated alkyl groups may also contain a ring structure selected from cyclopentane, cyclohexane, adamantane, norbenzene, and benzene rings at their ends or between carbon-carbon bonds.

[0034] R a It is a hydrocarbon group with 1 to 30 carbon atoms, which may contain halogen atoms or heteroatoms. Also, R a and the bonded S in the formula+ Two of the two aromatic rings can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

[0035] R 1 It can be a halogen atom, nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. When n2 is 2, 3, or 4, each R 1 They can be the same or different, and there are multiple Rs. 1 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0036] R 2 It can be a halogen atom, nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. When n4 is 2, 3, or 4, each R 2 They can be the same or different, and there are multiple Rs. 2 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0037] 2. The sulfonium salt as described in 1, which is represented by the following formula (A1).

[0038] [Chemistry 2]

[0039]

[0040] In the formula, n1~n4, L A R alk R a R 1 and R 2 Same as above.

[0041] n5 is 0 or 1. n6 is 0, 1, 2, 3 or 4.

[0042] R 3 It can be a halogen atom, nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. When n6 is 2, 3, or 4, each R 3 They can be the same or different, and there are multiple Rs. 3 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0043] 3. The sulfonium salt as described in 2, which is represented by the following formula (A2).

[0044] [Chemistry 3]

[0045]

[0046] In the formula, n2, n4, n6, L A R alk R a R 1 R 2 and R 3 Same as above.

[0047] 4. A quenching agent comprising a sulfite salt as described in any one of 1. to 3.

[0048] 5. A chemically amplified positive resist composition comprising a quencher as described in 4.

[0049] 6. The chemically amplified positive resist composition as described in 5 further contains a base polymer comprising a polymer that decomposes due to the action of acid and increases its solubility in alkaline developer.

[0050] 7. The chemically amplified positive resist composition as described in 6, wherein the aforementioned polymer contains repeating units represented by the following formula (B1).

[0051] [Chemistry 4]

[0052]

[0053] In the formula, a1 is 0 or 1. a2 is 0, 1 or 2. a3 is an integer that satisfies 0 ≤ a3 ≤ 5 + 2(a2) - a4. a4 is 1, 2 or 3.

[0054] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0055] R 11 It can be a halogen atom, a nitro group, a carboxyl group, or a saturated hydrocarbon group with 1 to 6 carbon atoms that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl group with 2 to 8 carbon atoms that can be substituted by a halogen atom.

[0056] A 1 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

[0057] 8. A chemically amplified positive resist composition as described in 6 or 7, wherein the aforementioned polymer contains repeating units represented by the following formula (B2-1).

[0058] [Chemistry 5]

[0059]

[0060] In the formula, R AIt can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0061] b1 is 0 or 1. b2 is 0, 1 or 2. b3 is an integer satisfying 0 ≤ b3 ≤ 5 + 2(b2) - b4. b4 is 1, 2 or 3. b5 is 0 or 1.

[0062] R 21 It is a halogen atom, or a saturated hydrocarbon group having 1 to 6 carbon atoms that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl group having 2 to 8 carbon atoms that can be substituted by a halogen atom.

[0063] A 2 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

[0064] X is an acid-labile group when b4 is 1, and is a hydrogen atom or an acid-labile group when b4 is 2 or 3, but at least one of them is an acid-labile group.

[0065] 9. The chemically amplified positive resist composition as described in any one of 6 to 8, wherein the aforementioned polymer contains a repeating unit represented by the following formula (B2-2).

[0066] [Chemistry 6]

[0067]

[0068] In the formula, c1 is 0, 1, or 2. c2 is 0, 1, or 2. c3 is 0, 1, 2, 3, 4, or 5. c4 is 0, 1, or 2.

[0069] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0070] R 22 and R 23 Each can be independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms, and R 22 and R 23 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0071] R 24 Each is independently a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkoxy group having 1 to 5 carbon atoms.

[0072] R 25 Each can be an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms.

[0073] A 3 It is a single bond, phenylene, naphthylene, or *-C(=O)-OA 31 -. A31 It may also contain hydroxyl groups, ether bonds, ester bonds, or lactone rings, and be an aliphatic alkylene group with 1 to 20 carbon atoms, or a phenylene or naphthylene group; * represents the atomic bond between the main chain and the carbon atom.

[0074] 10. The chemically amplified positive resist composition as described in any one of 6 to 9, wherein the polymer contains at least one repeating unit selected from the repeating unit represented by formula (B3), the repeating unit represented by formula (B4), and the repeating unit represented by formula (B5).

[0075] [Chemistry 7]

[0076]

[0077] In the formula, d is 0, 1, 2, 3, 4, 5, or 6. e is 0, 1, 2, 3, or 4. f1 is 0 or 1. f2 is 0, 1, or 2. f3 is 0, 1, 2, 3, 4, or 5.

[0078] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0079] R 31 and R 32 Each can be independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 6 carbon atoms that can also be substituted by a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that can also be substituted by a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that can also be substituted by a halogen atom.

[0080] R 33 It can be a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxygen group with 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms, a saturated hydrocarbon oxy hydrocarbon group with 2 to 20 carbon atoms, a saturated hydrocarbon thio hydrocarbon group with 2 to 20 carbon atoms, a halogen atom, a nitro group, or a cyano group, and can also be a hydroxyl group when f2 is 1 or 2.

[0081] A 4 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

[0082] 11. The chemically amplified positive resist composition as described in any one of 6 to 10, wherein the polymer contains at least one repeating unit selected from the following formula (B6), the following formula (B7), the following formula (B8), the following formula (B9), and the following formula (B10).

[0083] [Chemistry 8]

[0084]

[0085] In the formula, g1 and g2 are independently 0, 1, 2 or 3. h1 is 0 or 1. h2 is 0, 1, 2, 3 or 4. h3 is 0, 1, 2, 3 or 4. However, when h1 is 0, 0 ≤ h2 + h3 ≤ 4, and when h1 is 1, 0 ≤ h2 + h3 ≤ 6.

[0086] R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0087] Z 1 It is a single bond or may have substituents.

[0088] Z 2 For single bonds, **-C(=O)-OZ 21 -、**-C(=O)-NH-Z 21 -or**-OZ 21 -. Z 21 It is an aliphatic alkylene group, phenylene group, or a divalent group obtained by combining them, having 1 to 6 carbon atoms, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups.

[0089] Z 3 It can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0090] Z 4 It is a single bond, or an aliphatic alkylene group with 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by combining them, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups.

[0091] Z 5 Each can be a single bond, or may have substituents such as phenylene, naphthylene, or *-C(=O)-OZ. 51 -. Z 51 It is an aliphatic alkylene group, phenylene group, or naphthylene group with 1 to 10 carbon atoms, and the aliphatic alkylene group may also contain halogen atoms, hydroxyl groups, ether bonds, ester bonds, or lactone rings.

[0092] Z 6 It can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0093] Z 7 Each is independently a single bond, ***-Z 71 -C(=O)-O-、***-C(=O)-NH-Z 71 -or ***-OZ 71 -. Z 71 It may also contain heteroatoms and alkylene groups with 1 to 20 carbon atoms.

[0094] Z 8Each is independently a single bond, ****-Z 81 -C(=O)-O-、****-C(=O)-NH-Z 81 -or ****-OZ 81 -. Z 81 It may also contain heteroatoms and alkylene groups with 1 to 20 carbon atoms.

[0095] Z 9 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, *-C(=O)-OZ 91 -、*-C(=O)-N(H)-Z 91 -or *-OZ 91 -. Z 91 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group.

[0096] * indicates an atomic bond with a carbon atom in the main chain. ** indicates an atomic bond with Z. 1 The atomic bonds. *** indicates the relationship between Z and 6 Atomic bonds. **** represents the bond between Z and Z. 7 Atomic bonds.

[0097] L 1 It can be a single bond, ether bond, ester bond, carbonyl group, sulfonate bond, sulfonamide bond, carbonate bond or carbamate bond.

[0098] Rf 1 and Rf 2 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms.

[0099] Rf 3 and Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms.

[0100] Rf 5 and Rf 6 Each can be independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. However, all Rf 5 and Rf 6 It cannot be both hydrogen atoms at the same time.

[0101] Rf 7 It is a fluorine atom, a fluorinated alkyl group having 1 to 6 carbon atoms, a fluorinated alkoxy group having 1 to 6 carbon atoms, or a fluorinated alkyl thio group having 1 to 6 carbon atoms.

[0102] R 41 and R 42 Each can be independently a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. Also, R 41and R 42 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[0103] R 43 It is a halogen atom other than fluorine, or may contain a hydrocarbon group with 1 to 20 carbon atoms and heteroatoms. When h3 is 2, 3, or 4, each R 43 They can be the same or different, and there are multiple Rs. 43 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0104] M - It is a non-nucleophilic relative ion.

[0105] A + It is a ium cation.

[0106] 12. The chemically amplified positive resist composition as described in any one of 6 to 11, wherein, in all repeating units of the polymer contained in the aforementioned base polymer, the content of repeating units having an aromatic ring skeleton is 60 mol% or more.

[0107] 13. The chemically amplified positive resist composition as described in any one of 5 to 12, further comprising an organic solvent.

[0108] 14. The chemically amplified positive resist composition as described in any one of 5 to 13, further comprising a photoacid generator.

[0109] 15. The chemically amplified positive resist composition as described in any one of 5 to 14, further comprising at least one repeating unit selected from the repeating units represented by formula (E1), formula (E2), formula (E3), and formula (E4), and may also further comprise a polymer containing fluorine atoms selected from the repeating units represented by formula (E5) and formula (E6).

[0110] [Chemistry 9]

[0111]

[0112] In the formula, j1 is 1, 2, or 3. j2 is an integer satisfying 0 ≤ j2 ≤ 5 + 2(j3) - j1. j3 is 0 or 1. k is 1, 2, or 3.

[0113] R B Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0114] R C Each can be a hydrogen atom or a methyl group, independently.

[0115] R 201 R202 R 204 and R 205 Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms.

[0116] R 203 R 206 R 207 and R 208 Each of the following is independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-unstable group, and R 203 R 206 R 207 and R 208 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group can also be inserted between the carbon-carbon bonds.

[0117] R 209 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, which may be hydrogen atoms or may have heteroatom-containing groups inserted between carbon-carbon bonds.

[0118] R 210 It can also be a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which heteroatoms are inserted between carbon-carbon bonds.

[0119] R 211 It is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, and part of the -CH2- of the aforementioned saturated hydrocarbon group may also be replaced by an ester bond or an ether bond.

[0120] Z 1 It is a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms or a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms.

[0121] Z 2 It is a single bond, *-C(=O)-O- or *-C(=O)-NH-. * represents an atomic bond with a carbon atom in the main chain.

[0122] Z 3 For single bonds, -O-, *-C(=O)-OZ 31 -Z 32 -or *-C(=O)-NH-Z 31 -Z 32 -. Z 31 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms. Z 32 These are single bonds, ester bonds, ether bonds, or sulfonamide bonds. * indicates an atomic bond with a carbon atom in the main chain.

[0123] 16. The chemically amplified positive resist composition as described in any one of 5 to 15, further comprising a quencher other than the quencher described in 4.

[0124] 17. A method for forming a resist pattern, comprising the following steps:

[0125] A resist film is formed on a substrate using the chemically amplified positive resist composition as described in any one of 5. to 16.

[0126] The pattern was irradiated with high-energy rays onto the aforementioned resist film, and

[0127] The resist film that has been irradiated with the aforementioned pattern is developed using an alkaline developer.

[0128] 18. The method for forming a resist pattern as described in 17, wherein the aforementioned high-energy rays are EUV or EB with a wavelength of 3 to 15 nm.

[0129] 19. The resist patterning method as described in 17 or 18, wherein the outermost surface of the aforementioned substrate is made of a chromium-containing material.

[0130] 20. The method for forming a resist pattern as described in any one of 17 to 19, wherein the substrate is a blank photomask.

[0131] [The effects of the invention]

[0132] The chemically amplified positive resist composition of this invention can provide patterns with extremely high resolution and low LER in microfabrication technologies, especially in EB lithography and EUV lithography. Furthermore, the resist pattern exhibits good rectangularity after formation, making it suitable as a chemically amplified positive resist material. Detailed Implementation

[0133] The present invention will now be described in detail. Furthermore, in the following description, the structure represented by the chemical formula may contain asymmetric carbon, and mirror-image isomers and non-mirror-image isomers may exist; in such cases, each isomer is represented by a single formula. These isomers may be used individually or in mixtures of two or more.

[0134] [Sulfate]

[0135] The sulfonium salt of the present invention is represented by the following formula (A).

[0136] [Chemistry 10]

[0137]

[0138] In formula (A), n1 is 0 or 1. When n1 is 0, it is a benzene ring; when n1 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with n1 = 0. n2 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, n2 is preferably 0, 1, or 2. n3 is 0 or 1. When n3 is 0, it is a benzene ring; when n3 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with n3 = 0. n4 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, n4 is preferably 0, 1, or 2.

[0139] In formula (A), L A The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, or carbamate bonds. Among these, single bonds, ether bonds, ester bonds, and sulfonate bonds are preferred, with ether bonds and ester bonds being more ideal.

[0140] In formula (A), R alk It is an alkyl group having 6 to 18 carbon atoms or a fluorinated alkyl group having 4 to 18 carbon atoms.

[0141] R alk When it is an alkyl group having 6 to 18 carbon atoms, the alkyl group has at least one straight-chain structure with 6 or more carbon atoms. R alk Specific examples of alkyl groups with 6 to 18 carbon atoms include: 1-hexyl, 1-heptyl, 1-octyl, 1-nonyl, 1-decyl, 1-undecyl, 1-dodecyl, 1-tridecyl, 1-tetradecyl, 1-hexadecyl, 1-hexadecyl, 1-octadecyl, octane-2-yl, decane-2-yl, decane-4-yl, octadecane-8-yl, 7,7-dimethyloctyl, 7,7-diethylnonyl, 4-butyldodecyl, etc. Furthermore, a portion of the -CH2- group of the aforementioned alkyl groups may be replaced by an ether bond or a carbonyl group, and they may also have a ring structure at the end or between carbon-carbon bonds, such as a cyclopentane ring, a cyclohexane ring, an adamantane ring, a norbornene ring, or a benzene ring. alk It should preferably be a straight-chain alkyl group or a straight-chain ethylene glycol dimethyl ether chain.

[0142] R alk When it is a fluorinated alkyl group having 4 to 18 carbon atoms, the fluorinated alkyl group has at least two groups selected from -CF2- and -CF3. alkSpecific examples of fluorinated alkyl groups with 4 to 18 carbon atoms include: 1-butyl, 1-pentyl, 1-hexyl, 1-heptyl, 1-octyl, 1-nonyl, 1-decyl, 1-undecyl, 1-dodecyl, 1-tridecyl, 1-tetradecyl, 1-hexadecyl, 1-hexadecyl, 1-octadecyl, octane-2-yl, decane-2-yl, decane-4-yl, octadecane-8-yl, 7,7-dimethyloctyl, 7,7-diethylnonyl, 4-butyldodecyl, etc., where some or all of the hydrogen atoms are replaced by fluorine atoms. Furthermore, a portion of the -CH2- group of the aforementioned fluorinated alkyl groups may also be replaced by an ether bond or a carbonyl group, and the terminal or carbon-carbon bonds may also have a ring structure, such as a cyclopentane ring, a cyclohexane ring, an adamantane ring, a norcamphenic ring, or a benzene ring.

[0143] R alk It should be as shown below, but is not limited to these. Additionally, in the following formula, dashed lines represent atomic bonds.

[0144] [Chemistry 11]

[0145]

[0146] In formula (A), R a It is a hydrocarbon group with 1 to 30 carbon atoms, which may contain halogen atoms or heteroatoms.

[0147] R a Specific examples of halogen atoms that can be represented include: fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc.

[0148] R aThe hydrocarbon group represented can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornel, and adamantyl; alkenyl groups with 2 to 30 carbon atoms such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclohexenyl; aryl groups with 6 to 30 carbon atoms such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 30 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining these groups, which should preferably be aryl. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and some of the -CH2- in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0149] Also, R a and the bonded S in the formula + Two of the two aromatic rings can also bond to each other and form a ring together with the sulfur atoms they are bonded to. In this case, the structure of the aforementioned ring can be represented by the following formulas, etc.

[0150] [Chemistry 12]

[0151]

[0152] In the formula, the dashed lines represent the atomic bonds between the remaining substituent and the other substituent.

[0153] In formula (A), R 1The halogen atom can be a nitro group, a cyano group, a hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms. The aforementioned halogen atom is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, with fluorine or iodine atoms being more preferred. Furthermore, the aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecanyl, octadecyl, nonadecanyl, and eicosyl; cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornel, and adamantyl; alkenyl groups with 2 to 20 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 20 carbon atoms, such as cyclohexenyl; aryl groups with 6 to 20 carbon atoms, such as phenyl and naphthyl; aralkyl groups with 7 to 20 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining these. Among these, aryl groups are preferred. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon group can also be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. This can result in the presence of hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone, sulfonate, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. Also, when n2 is 2, 3, or 4, each R... 1 They can be the same or different.

[0154] Furthermore, when n2 is 2, 3, or 4, multiple R 1 They can also bond with each other and form rings together with the carbon atoms they are bonded to. Specific examples of rings formed in this case include: cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0155] In formula (A), R 2The halogen atom can be a nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon oxy group with 1 to 20 carbon atoms containing heteroatoms; or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. The aforementioned halogen atom is preferably a fluorine atom, chlorine atom, bromine atom, or iodine atom, with fluorine or iodine atom being more preferred. Furthermore, the aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as R. 1 Examples of hydrocarbon groups are similar, but not limited to these. Also, when n4 is 2, 3, or 4, each R... 2 They can be the same or different.

[0156] Furthermore, when n4 is 2, 3, or 4, multiple R 2 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Several specific examples of rings formed in this case can be listed (R). 1 Specific examples of rings that can be formed by mutual bonding and together with the carbon atoms they are bonded to are similar to, but not limited to, those formed by mutual bonding and together with the carbon atoms they are bonded to.

[0157] The sulfonium salt represented by formula (A) should preferably be represented by the following formula (A1).

[0158] [Chemistry 13]

[0159]

[0160] In the formula, n1~n4, L A R alk R a R 1 and R 2 Same as above.

[0161] In formula (A1), n5 is 0 or 1. When n5 is 0, it is a benzene ring; when n5 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with n5 of 0. n6 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, n6 is preferable to be 0, 1, or 2.

[0162] In equation (A1), R 3 The halogen atom can be a nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. The aforementioned halogen atom is preferably a fluorine atom, chlorine atom, bromine atom, or iodine atom, with fluorine or iodine atom being more preferred. Furthermore, the aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given and illustrated in the description of formula (A) as R. 1 Examples of hydrocarbon groups are similar, but not limited to these. Also, when n6 is 2, 3, or 4, each R... 3 They can be the same or different.

[0163] Furthermore, when n6 is 2, 3, or 4, multiple R 3 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Specific examples of the rings formed in this case can be listed and illustrated in the explanation of formula (A1) as multiple R 1 Specific examples of rings that can be formed by mutual bonding and together with the carbon atoms they are bonded to are similar to, but not limited to, those formed by mutual bonding and together with the carbon atoms they are bonded to.

[0164] The sulfonium salt represented by formula (A1) should preferably be represented by formula (A2).

[0165] [Chemistry 14]

[0166]

[0167] In the formula, n2, n4, n6, L A R alk R a R 1 R 2 and R 3 Same as above. Ideal examples of sulfonium salts represented by equation (A) can be listed below, but are not limited thereto.

[0168] [Chemistry 15]

[0169]

[0170] [Chemistry 16]

[0171]

[0172] [Chemistry 17]

[0173]

[0174] [Chemistry 18]

[0175]

[0176] [Chemistry 19]

[0177]

[0178] [Chemistry 20]

[0179]

[0180] [Chemistry 21]

[0181]

[0182] [Chemistry 22]

[0183]

[0184] [Chemistry 23]

[0185]

[0186] [Chemistry 24]

[0187]

[0188] [Chemistry 25]

[0189]

[0190] [Chemistry 26]

[0191]

[0192] [Chemistry 27]

[0193]

[0194] [Chemistry 28]

[0195]

[0196] [Chemistry 29]

[0197]

[0198] [Chemistry 30]

[0199]

[0200] [Chemistry 31]

[0201]

[0202] The sulfonium salt of the present invention can be synthesized using known methods. Specifically, the synthesis method described in paragraph

[0019] of Japanese Patent No. 6583136 can be used, but it is not limited thereto.

[0203] The sulfonium salt represented by formula (A) is characterized by a basic carboxylate anion structure and a chain of 6-18 carbon alkyl groups or a chain of 4-18 carbon fluorinated alkyl groups on the aromatic ring forming the sulfonium cation. It is believed that the aforementioned alkyl and fluorinated alkyl groups increase solvent solubility and have high lipid solubility, therefore the sulfonium salt represented by formula (A) is distributed in the upper layer of the resist film. Especially in EB lithography, when depicting an electron beam, the forward scattering caused by the electron beam cannot be avoided in the exposure area. When using conventional quenchers, there is a concern that the deprotection reaction in the upper part of the pattern may be excessive, resulting in a rounded shape at the top of the pattern. However, by using the quencher of the present invention, excessive deprotection reaction in the upper part of the pattern can be effectively suppressed, and the pattern can be corrected to a rectangle. Furthermore, the high basicity of the carboxylate anion located within the same molecule can control the acid diffusion of the generated acid and effectively quench it. It is believed that by utilizing these synergistic effects, when using the matte salt of the present invention, patterns with good resolution, high contrast, good CDU, and small LER can be obtained, as well as patterns with good rectangularity can be obtained.

[0204] The matte salt of the present invention can be ideally used as a quenching agent.

[0205] [Chemical amplification positive resist composition]

[0206] [(A) Quenching agent]

[0207] The chemically amplified positive resist composition of the present invention, in terms of component (A), contains a quencher composed of a sulfonium salt represented by formula (A) as an essential component. Furthermore, in the present invention, a quencher refers to a compound that captures acids that generate acid-producing agents. This suppresses the diffusion rate of acids that generate acid-producing agents within the resist film, and even when using a substrate whose outermost surface is made of a chromium-containing material, the influence of acids generated within the resist film on the chromium-containing material can be suppressed.

[0208] In the chemically amplified positive resist composition of the present invention, the content of (A) quencher relative to 80 parts by mass of the base polymer (B) described later is preferably 0 to 50 parts by mass, and more preferably 0.1 to 40 parts by mass. If the content of the quencher is within the aforementioned range, the generated acid can be effectively captured, and a good pattern shape can be obtained. Furthermore, good storage stability is also achieved. (A) Quencher can be used alone or in combination of two or more types.

[0209] [(B) Basic Polymer]

[0210] The resist composition of the present invention contains a base polymer comprising a polymer that decomposes due to the action of acid and increases the solubility in alkaline developing solutions as component (B).

[0211] The aforementioned polymer is preferably a polymer containing repeating units represented by the following formula (B1) (hereinafter also referred to as repeating unit B1).

[0212] [Chemistry 32]

[0213]

[0214] In formula (B1), a1 is 0 or 1. a2 is 0, 1, or 2; 0 represents the benzene skeleton, 1 represents the naphthalene skeleton, and 2 represents the anthracene skeleton. a3 is an integer satisfying 0 ≤ a3 ≤ 5 + 2(a2) - a4. a4 is 1, 2, or 3. When a2 is 0, it is preferable that a3 is 0, 1, 2, or 3, and a4 is 1, 2, or 3. When a2 is 1 or 2, it is preferable that a3 is 0, 1, 2, 3, or 4, and a4 is 1, 2, or 3.

[0215] In equation (B1), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0216] In equation (B1), R 11 The saturated hydrocarbon group can be a halogen atom, nitro group, carboxyl group, or a saturated hydrocarbon group with 1 to 6 carbon atoms that can be substituted by a halogen atom; a saturated hydrocarbon oxy group with 1 to 6 carbon atoms that can be substituted by a halogen atom; or a saturated hydrocarbon carbonyl oxy group with 2 to 8 carbon atoms that can be substituted by a halogen atom. The saturated hydrocarbon group, saturated hydrocarbon oxy group, and saturated hydrocarbon carbonyl oxy group can be any of the following: linear, branched, or cyclic. Specific examples include: alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; and groups obtained by combining them. If the number of carbon atoms is below the upper limit, the solubility in alkaline developing solutions is good. When a3 is 2 or higher, each R... 11 They can be the same or different.

[0217] In equation (B1), A 1It is a single bond or a saturated alkylene group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated alkylene group may also be replaced by -O-. The aforementioned saturated alkylene group can be any of the following: linear, branched, or cyclic. Specific examples include: methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers, etc., which are alkyl diyl groups with 1 to 10 carbon atoms; cyclopropane diyl, cyclobutane diyl, cyclopentane diyl, cyclohexane diyl, etc., which are cyclic saturated alkylene groups with 3 to 10 carbon atoms; and groups obtained by combining them. When the aforementioned saturated alkylene group contains an ether bond, when a1 in formula (B1) is 1, it can be inserted at any position other than between the carbon atom at the α-position and the carbon atom at the β-position relative to the ester oxygen atom. Furthermore, when a1 is 0, the atom bonded to the main chain becomes an ether oxygen atom, and a second ether bond can be inserted at any position other than between the carbon atom at the α-position and the carbon atom at the β-position relative to this ether oxygen atom. In addition, if the number of carbon atoms in the aforementioned saturated hydrocarbon group is 10 or less, sufficient solubility in alkaline developing solution can be obtained, which is ideal.

[0218] a1 is 0 and A 1 When it is a single bond, that is, the aromatic ring is directly bonded to the polymer backbone (i.e., it does not have a linking group (-C(=O)-OA)). 1 When repeating unit B1, ideal examples can be listed from units such as 3-hydroxystyrene, 4-hydroxystyrene, 5-hydroxy-2-vinylnaphthalene, 6-hydroxy-2-vinylnaphthalene, etc. Specifically, those shown below can be listed, but are not limited to. Additionally, in the following formula, R... A Same as above.

[0219] [Chemistry 33]

[0220]

[0221] [Chemistry 34]

[0222]

[0223] [Chemistry 35]

[0224]

[0225] a1 is 1 (that is, it has -C(=O)-OA) 1 When R is used as a linking group, ideal examples of repeating unit B1 can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0226] [Chemistry 36]

[0227]

[0228] [Chemistry 37]

[0229]

[0230] [Chemistry 38]

[0231]

[0232] [Chemistry 39]

[0233]

[0234] [Chemistry 40]

[0235]

[0236] The content of repeating unit B1 in all repeating units constituting the aforementioned polymer is preferably 15-90 mol%, and more preferably 15-80 mol%. However, if the polymer described later contains at least one of the repeating units represented by formula (B3) and formula (B4) that provide higher etch resistance, and the unit has a phenolic hydroxyl group as a substituent, its ratio should also be added and set within the aforementioned range. Repeating unit B1 may be used alone or in combination of two or more.

[0237] In order to provide the characteristic that the exposed part of the aforementioned polymer can be dissolved in alkaline developer as a positive resist composition, it is advisable to contain repeating units with acidic functional groups protected by acid-instable groups, that is, repeating units that are protected by acid-instable groups and become alkali-soluble due to the action of acid (hereinafter also referred to as repeating unit B2).

[0238] The ideal example of repeating unit B2 can be represented by the following formula (B2-1) (hereinafter also called repeating unit B2-1).

[0239] [Chemistry 41]

[0240]

[0241] In formula (B2-1), b1 is 0 or 1. b2 is 0, 1, or 2; 0 indicates a benzene skeleton, 1 indicates naphthalene, and 2 indicates anthracene. b3 is an integer satisfying 0 ≤ b3 ≤ 5 + 2(b2) - b4. b4 is 1, 2, or 3. b5 is 0 or 1. When b2 is 0, it is preferable that b3 is 0, 1, 2, or 3, and b4 is 1, 2, or 3. When b2 is 1 or 2, it is preferable that b3 is 0, 1, 2, 3, or 4, and b4 is 1, 2, or 3.

[0242] In equation (B2-1), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0243] In equation (B2-1), R 21The carbon group can be a 1-6 carbon saturated hydrocarbon group, which may be substituted with a halogen atom or a halogen atom; a 1-6 carbon saturated hydrocarbon oxy group, which may be substituted with a halogen atom or a 2-8 carbon saturated hydrocarbon carbonyl oxy group, which may be substituted with a halogen atom. The saturated hydrocarbon group, as well as the saturated hydrocarbon carbonyl oxy group and the saturated hydrocarbon oxy group, can be linear, branched, or cyclic. Specific examples include: alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; and groups obtained by combining them. If the number of carbon atoms is below the upper limit, the solubility in alkaline developing solutions is good. When b3 is 2 or more, each R... 21 They can be the same or different.

[0244] In equation (B2-1), A 2 It is a single bond or a saturated alkylene group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated alkylene group may also be replaced by -O-. The aforementioned saturated alkylene group can be any of the following: linear, branched, or cyclic. Specific examples include: methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers, etc., which are alkyl diyl groups with 1 to 10 carbon atoms; cyclopropane diyl, cyclobutane diyl, cyclopentane diyl, cyclohexane diyl, etc., which are cyclic saturated alkylene groups with 3 to 10 carbon atoms; and groups obtained by combining them. When the aforementioned saturated alkylene group contains an ether bond, when b1 in formula (B2-1) is 1, it can be inserted at any position other than between the carbon atom at the α-position and the carbon atom at the β-position relative to the ester oxygen atom. Furthermore, when b1 is 0, the atom bonded to the main chain becomes an ether oxygen atom, and a second ether bond can be inserted at any position other than between the carbon atom at the α-position and the carbon atom at the β-position relative to this ether oxygen atom. In addition, if the number of carbon atoms in the aforementioned saturated hydrocarbon group is 10 or less, sufficient solubility in alkaline developing solution can be obtained, which is ideal.

[0245] In formula (B2-1), when b4 is 1, X is an acid-labile group. When b4 is 2 or 3, X is either a hydrogen atom or an acid-labile group independently, but at least one is an acid-labile group. That is, the repeating unit B2-1 is either a phenolic hydroxyl group bonded to an aromatic ring that is protected by an acid-labile group, or a carboxyl group bonded to an aromatic ring that is protected by an acid-labile group. There are no particular restrictions on the use of the aforementioned acid-labile groups if they are found in various known chemically amplified positive resist compositions and are removed by acid to provide an acidic group.

[0246] Examples of the aforementioned acid-labile groups include tertiary saturated hydrocarbon groups. For the purpose of obtaining the monomers for polymerization by distillation, the aforementioned tertiary saturated hydrocarbon groups should preferably have 4 to 18 carbon atoms.

[0247] The saturated hydrocarbon groups bonded to the aforementioned tertiary carbon atoms preferably have 1 to 15 carbon atoms. These saturated hydrocarbon groups with 1 to 15 carbon atoms can be linear, branched, or cyclic, and their carbon-carbon bonds may contain ether bonds, carbonyl groups, or other functional groups containing oxygen atoms. Furthermore, the saturated hydrocarbon groups bonded to the tertiary carbon atoms can also bond to each other and form rings together with the tertiary carbon atoms they are bonded to.

[0248] Examples of the aforementioned alkyl substituents include: methyl, ethyl, propyl, adamantyl, norbornel, tetrahydrofuran-2-yl, 7-oxanorborne-2-yl, cyclopentyl, 2-tetrahydrofuranyl, tricyclic [5.2.1.0] 2,6 ] Decyl, 8-ethyl-8-tricyclo[5.2.1.0 2,6 Decyl, 3-methyl-3-tetracyclo[4.4.0.1] 2,5 .1 7,10 Dodecyl, tetracyclo[4.4.0.1] 2,5 .1 7,10 Dodecyl, 3-oxo-1-cyclohexyl, etc.

[0249] The aforementioned tertiary saturated hydrocarbon groups can be listed as follows: tert-butyl, tert-pentyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1,2-trimethylpropyl, 1-adamantyl-1-methylethyl, 1-methyl-1-(2-norborneol)ethyl, 1-methyl-1-(tetrahydrofuran-2-yl)ethyl, 1-methyl-1-(7-oxanorborneol-2-yl)ethyl, 1-methylcyclopentyl, 1-ethyl Cyclopentyl, 1-propylcyclopentyl, 1-cyclopentylcyclopentyl, 1-cyclohexylcyclopentyl, 1-(2-tetrahydrofuranyl)cyclopentyl, 1-(7-oxanorbornen-2-yl)cyclopentyl, 1-methylcyclohexyl, 1-ethylcyclohexyl, 1-cyclopentylcyclohexyl, 1-cyclohexylcyclohexyl, 2-methyl-2-norbornenyl, 2-ethyl-2-norbornenyl, 8-methyl-8-tricyclo[5.2.1.0] 2,6 ] Decyl, 8-ethyl-8-tricyclo[5.2.1.0 2,6 Decyl, 3-methyl-3-tetracyclo[4.4.0.1] 2,5 .1 7,10 Dodecyl, 3-ethyl-3-tetracyclo[4.4.0.1] 2 ,5 .1 7,10 Dodecyl, 2-methyl-2-adamantyl, 2-ethyl-2-adamantyl, 1-methyl-3-oxo-1-cyclohexyl, 1-methyl-1-(tetrahydrofuran-2-yl)ethyl, 5-hydroxy-2-methyl-2-adamantyl, 5-hydroxy-2-ethyl-2-adamantyl, but not limited thereto.

[0250] Furthermore, the aforementioned acid-indestructible groups can be exemplified by groups represented by formula (B2-1-1). Groups represented by formula (B2-1-1) are often used as acid-indestructible groups, and are a useful option as acid-indestructible groups that stably provide a more rectangular pattern at the interface between the pattern and the substrate. When X is a group represented by formula (B2-1-1), an acetal structure is formed.

[0251] [Chemistry 42]

[0252]

[0253] In the formula, the dashed lines represent atomic bonds.

[0254] In equation (B2-1-1), R L1 It is a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. The aforementioned saturated hydrocarbon group can be any of the following: straight-chain, branched, or cyclic.

[0255] R L1 The appropriate group should be selected based on its sensitivity to the acid's decomposition potential. For example, if the design aims to ensure high stability while allowing decomposition by a strong acid, a group with a hydrogen atom or a tertiary carbon atom bonded to the acetal carbon is preferable. This is achieved through the R group formed by the tertiary carbon atom and the acetal carbon. L1 Examples include tert-butyl, tert-pentyl, and 1-adamantyl, but these are not limited to. For designs requiring high sensitivity to pH changes and high reactivity, straight-chain alkyl groups are preferable. While the choice also depends on the combination of acid-generating and quenching agents incorporated into the resist composition, regarding R... L2 In particular, when designed with a larger terminal alkyl group and a large change in solubility due to decomposition, R L1 The carbon atom bonded to the acetal carbon should be a secondary carbon atom. Utilizing the R-type bond between the secondary carbon atom and the acetal carbon... L1 Examples include isopropyl, sec-butyl, cyclopentyl, cyclohexyl, etc., but are not limited to these.

[0256] In equation (B2-1-1), R L2 The hydrocarbon group has 1 to 30 carbon atoms. This hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. A portion of the -CH2- group can be replaced by heteroatoms such as oxygen or sulfur atoms, resulting in ether bonds or thioether bonds. Specific examples of the aforementioned hydrocarbon group include saturated hydrocarbon groups with 1 to 30 carbon atoms and aryl groups with 6 to 30 carbon atoms. Especially in the formation of fine patterns, in order to obtain higher resolution, R... L2 It should preferably be a hydrocarbon group with 1 to 6 carbon atoms. R L2When the hydrocarbon group has 1 to 6 carbon atoms, the alcohol produced after the deprotection reaction caused by the acid is water-soluble. Therefore, when a positive pattern is formed using an alkaline developer, it will dissolve in the developer, thus suppressing residue defects in the exposed area.

[0257] Ideal examples of the groups represented by formula (B2-1-1) can be listed below, but are not limited to these. Additionally, in the following formula, R... L1 As mentioned above, dashed lines represent atomic bonds.

[0258] [Chemistry 43]

[0259]

[0260] [Chemistry 44]

[0261]

[0262] Other acid-labile groups can also be formed by replacing the hydrogen atom of the phenolic hydroxyl group with -CH2COO- (tertiary saturated hydrocarbon group). In this case, the aforementioned tertiary saturated hydrocarbon group can be the same as the tertiary saturated hydrocarbon group used for the protection of the aforementioned phenolic hydroxyl group.

[0263] Furthermore, repeating unit B2 can also be represented by the repeating unit (B2-2) below (hereinafter also referred to as repeating unit B2-2). The dissolution rate of repeating unit B2-2 in the exposure section will be higher, so it is a useful option as a unit containing acid-instable groups that provides good performance for linewidth variation of the developing load.

[0264] [Chemistry 45]

[0265]

[0266] In equation (B2-2), c1 is 0, 1, or 2. c2 is 0, 1, or 2. c3 is 0, 1, 2, 3, 4, or 5. c4 is 0, 1, or 2.

[0267] In equation (B2-2), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0268] In equation (B2-2), R 22 and R 23 Each can be independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms, and R 22 and R 23 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0269] In equation (B2-2), R 24 Each is independently a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkoxy group having 1 to 5 carbon atoms.

[0270] In equation (B2-2), R 25 Each can be an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms.

[0271] In equation (B2-2), A 3 It is a single bond, phenylene, naphthylene, or *-C(=O)-OA 31 -. A 31 It may also contain hydroxyl groups, ether bonds, ester bonds, or lactone rings, and consist of aliphatic alkylene groups with 1 to 20 carbon atoms, or phenylene or naphthylene groups. * indicates an atomic bond with the carbon atoms of the main chain.

[0272] Ideal examples of repeating unit B2-2 can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0273] [Chemistry 46]

[0274]

[0275] [Chemistry 47]

[0276]

[0277] The content of repeating unit B2 in all repeating units constituting the aforementioned polymer is preferably 5-95 mol%, and more preferably 20-80 mol%. Repeating unit B2 can be used alone or in combination of two or more types.

[0278] The aforementioned polymer may also contain at least one of the repeating units represented by formula (B3) (hereinafter also referred to as repeating unit B3), the repeating unit represented by formula (B4) (hereinafter also referred to as repeating unit B4), and the repeating unit represented by formula (B5) (hereinafter also referred to as repeating unit B5).

[0279] [Chemistry 48]

[0280]

[0281] In equations (B3) and (B4), d is 0, 1, 2, 3, 4, 5, or 6. e is 0, 1, 2, 3, or 4.

[0282] In equations (B3) and (B4), R 31 and R 32 Each R can be independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 6 carbon atoms that can be substituted by a halogen atom, a saturated hydrocarbon carbonyloxy group with 1 to 6 carbon atoms that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group with 2 to 8 carbon atoms that can be substituted by a halogen atom. The aforementioned saturated hydrocarbon group, saturated hydrocarbon carbonyloxy group, and saturated hydrocarbon carbonyloxy group can be any of the following: linear, branched, or cyclic. When d is 2 or more, each R... 31They can be the same or different. When e is 2 or higher, each R... 32 They can be the same or different.

[0283] In formula (B5), f1 is 0 or 1. f2 is 0, 1, or 2; when it is 0, it is a benzene skeleton; when it is 1, it is a naphthalene skeleton; and when it is 2, it is an anthracene skeleton. f3 is 0, 1, 2, 3, 4, or 5. When f2 is 0, f3 should preferably be 0, 1, 2, or 3; when f2 is 1 or 2, f3 should preferably be 0, 1, 2, 3, or 4.

[0284] In equation (B5), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0285] In equation (B5), R 33 The group can be a saturated hydrocarbon group (1-20 carbon atoms), a saturated hydrocarbon oxy group (1-20 carbon atoms), a saturated hydrocarbon carbonyl oxy group (2-20 carbon atoms), a saturated hydrocarbon oxy hydrocarbon group (2-20 carbon atoms), a saturated hydrocarbon thioalkyl hydrocarbon group (2-20 carbon atoms), a halogen atom, a nitro group, or a cyano group, and when f2 is 1 or 2, it can also be a hydroxyl group. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyl oxy group, saturated hydrocarbon oxy hydrocarbon group, and saturated hydrocarbon thioalkyl hydrocarbon group can be any of the following: linear, branched, or cyclic. When f3 is 2 or more, each R... 33 They can be the same or different.

[0286] In equation (B5), A 4 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group may also be replaced by -O-. The aforementioned saturated hydrocarbon group can be linear, branched, or cyclic, and specific examples can be listed in A of formula (B1). 1 The same examples are illustrated in the description.

[0287] When at least one of repeating units B3 to B5 is used as a constituent unit of the aforementioned polymer, in addition to obtaining the etching resistance of the aromatic ring, the effect of improving etching resistance and EB irradiation resistance during pattern inspection can also be obtained by adding a ring structure to the main chain.

[0288] To achieve the effect of improving etching resistance, the content of repeating units B3 to B5 should preferably be 5 mol% or more among all repeating units constituting the aforementioned polymer. Furthermore, the content of repeating units B3 to B5 should preferably be 25 mol% or less, and more preferably 20 mol% or less, among all repeating units constituting the aforementioned polymer. Ideally, if the amount introduced when there are no functional groups, or when the functional group is other than hydroxyl groups, is 25 mol% or less, there will be no concern about development defects, and therefore this is preferable. Repeating units B3 to B5 can be used alone or in combination of two or more.

[0289] If the aforementioned polymer contains repeating unit B1, repeating unit B2, and at least one of repeating units selected from B3 to B5, it is ideal to achieve a good balance between high etch resistance and resolution. In this case, these repeating units preferably contain 60 mol% or more, more preferably 70 mol% or more, more preferably 80 mol% or more, and more preferably 90 mol% or more in all the repeating units of the aforementioned polymer.

[0290] The aforementioned polymer may also contain at least one of the following: repeating unit represented by formula (B6) (hereinafter also referred to as repeating unit B6), repeating unit represented by formula (B7) (hereinafter also referred to as repeating unit B7), repeating unit represented by formula (B8) (hereinafter also referred to as repeating unit B8), repeating unit represented by formula (B9) (hereinafter also referred to as repeating unit B9), and repeating unit represented by formula (B10) (hereinafter also referred to as repeating unit B10).

[0291] [Chemistry 49]

[0292]

[0293] In equations (B6) to (B10), R A Each can be independently composed of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 It is a single bond or may have substituents. Z 2 For single bonds, **-C(=O)-OZ 21 -、**-C(=O)-NH-Z 21 -or**-OZ 21 -. Z 21 It is a divalent group consisting of an aliphatic hydrocarbon group, a phenylene group, or a combination thereof, having 1 to 6 carbon atoms, and may also contain a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. 3 It can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. 4 It is a single bond, or an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by combining them, and may also contain a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. 5 Each can be a single bond, or may have substituents such as phenylene, naphthylene, or *-C(=O)-OZ. 51 -. Z 51 It is an aliphatic alkylene group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the aliphatic alkylene group may also contain a halogen atom, a hydroxyl group, an ether bond, an ester bond, or an lactone ring. 6 It can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. 7 Each is independently a single bond, ***-Z 71-C(=O)-O-、***-C(=O)-NH-Z 71 -or ***-OZ 71 -. Z 71 It can also contain alkylene groups with 1 to 20 carbon atoms, which may also contain heteroatoms. Z 8 Each is independently a single bond, ****-Z 81 -C(=O)-O-、****-C(=O)-NH-Z 81 -or ****-OZ 81 -. Z 81 It can also contain alkylene groups with 1 to 20 carbon atoms, which may also contain heteroatoms. Z 9 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, *-C(=O)-OZ 91 -、*-C(=O)-N(H)-Z 91 -or *-OZ 91 -. Z 91 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group. * indicates an atomic bond with the carbon atom of the main chain. ** indicates a bond with Z. 1 The atomic bonds. *** indicates the relationship between Z and 6 Atomic bonds. **** represents the bond between Z and Z. 7 Atomic bonds.

[0294] Z 21 Z 51 and Z 91 The aliphatic alkyl sub-group can be any of the following: linear, branched, or cyclic. Specific examples include: methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, 1,1-dimethylethane-1,2-diyl, pentane-1,5-diyl, 2-methylbutane-1,2-diyl, hexane-1,6-diyl, etc.; cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, cyclohexanediyl, etc.; and groups obtained by combining them.

[0295] Z 71 and Z 81 The sub-hydrocarbon group represented may contain heteroatoms and can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples are listed below, but are not limited to these.

[0296] [Transformation 50]

[0297]

[0298] In the formula, the dashed lines represent atomic bonds.

[0299] In equation (B6), R 41 and R 42 Each of the above-mentioned hydrocarbon groups can be independently a hydrocarbon group with 1 to 20 carbon atoms, and may also contain heteroatoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 20 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 20 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 20 carbon atoms such as cyclohexenyl; aryl groups with 6 to 20 carbon atoms such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 20 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them, which are preferably aryl groups. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and some of the -CH2- in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0300] Also, R 41 and R 42 They can also bond to each other and form rings together with the sulfur atoms they are bonded to. Specific examples of the aforementioned rings can be shown in the following formulas, etc.

[0301] [Chemistry 51]

[0302]

[0303] In the formula, the dashed line represents Z. 4 Atomic bonds.

[0304] Specific examples of the cation in repeating unit B6 can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0305] [Chemistry 52]

[0306]

[0307] [Chemistry 53]

[0308]

[0309] [Chemistry 54]

[0310]

[0311] [Chemistry 55]

[0312]

[0313] [Chemistry 56]

[0314]

[0315] [Chemistry 57]

[0316]

[0317] [Chem.58]

[0318]

[0319] [Chemistry 59]

[0320]

[0321] [Transformation 60]

[0322]

[0323] [Chemistry 61]

[0324]

[0325] In equation (B6), M - These are non-nucleophilic relative ions. The aforementioned non-nucleophilic relative ions are preferably halide ions, sulfonate anions, imide anions, and methylated acid anions. Specific examples of the aforementioned halide ions include chloride ions and bromide ions. Specific examples of the aforementioned sulfonate anions include: trifluoromethanesulfonate ions, 1,1,1-trifluoroethanesulfonate ions, nonafluorobutanesulfonate ions, and other fluoroalkyl sulfonate ions; toluenesulfonate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, 1,2,3,4,5-pentafluorobenzenesulfonate ions, and other aryl sulfonate ions; methanesulfonate ions, butanesulfonate ions, and other alkyl sulfonate ions, etc. Specific examples of the aforementioned imide anions (imide ions) include: bis(trifluoromethylsulfonyl)imide ion, bis(perfluoroethylsulfonyl)imide ion, bis(perfluorobutylsulfonyl)imide ion, etc. Specific examples of the aforementioned methylated anions (methylated ions) include: tris(trifluoromethylsulfonyl)methylated ion, tris(perfluoroethylsulfonyl)methylated ion, etc.

[0326] Other examples of the aforementioned non-nucleophilic relative ions can be listed as anions represented by any of the formulas (B6-1) to (B6-4).

[0327] [Chemistry 62]

[0328]

[0329] In equation (B6-1), R fa The hydrocarbon group consists of fluorine atoms, or may contain heteroatoms, and has 1 to 40 carbon atoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as R in the following formula (B6-1-1). fa1 The same example represents hydrocarbon groups.

[0330] The anion represented by formula (B6-1) should preferably be represented by the following formula (B6-1-1).

[0331] [Chemistry 63]

[0332]

[0333] In equation (B6-1-1), Q 1 and Q 2 Each of the following is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; to improve solvent solubility, at least one of these is preferably trifluoromethyl. m is 0, 1, 2, 3, or 4, with 1 being particularly preferred. R fa1 It can also contain hydrocarbon groups with 1 to 35 carbon atoms that are heteroatoms. The aforementioned heteroatoms are preferably oxygen, nitrogen, sulfur, halogen, etc., with oxygen atoms being more preferred. Considering that the aforementioned hydrocarbon groups can obtain high resolution in the formation of fine patterns, those with 6 to 30 carbon atoms are particularly preferred.

[0334] In equation (B6-1-1), R fa1The hydrocarbon group represented by carbon number 1 to 35 can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 35 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecanyl, and eicosyl; cyclic saturated hydrocarbon groups with 3 to 35 carbon atoms, such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norcamphenyl, norcamphenylmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl; unsaturated aliphatic hydrocarbon groups with 2 to 35 carbon atoms, such as 2-propenyl and 3-cyclohexenyl; aryl groups with 6 to 35 carbon atoms, such as phenyl, 1-naphthyl, 2-naphthyl, and 9-fluorenyl; aralkyl groups with 7 to 35 carbon atoms, such as benzyl and diphenylmethyl; and groups obtained by combining them.

[0335] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms. Similarly, a portion of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. This can result in the presence of hydroxyl, fluorine, chlorine, bromine, iodine, cyano, nitro, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. Specific examples of hydrocarbon groups containing heteroatoms include: tetrahydrofuranyl, methoxymethyl, ethoxymethyl, methylthiomethyl, acetamidemethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetoxymethyl, 2-carboxy-1-cyclohexyl, 2-oxopropyl, 4-oxo-1-adamantyl, 3-oxocyclohexyl, etc.

[0336] In formula (B6-1-1), L a1 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, or carbamate bonds. From a synthetic point of view, ether bonds or ester bonds are preferred, with ester bonds being even better.

[0337] Specific examples of anions represented by formula (B6-1) are shown below, but are not limited to these. Additionally, in the following formula, Q... 1 As mentioned above, Ac is an acetyl group.

[0338] [Chemistry 64]

[0339]

[0340] [Chemistry 65]

[0341]

[0342] [Chemistry 66]

[0343]

[0344] [Chemistry 67]

[0345]

[0346] [Chemistry 68]

[0347]

[0348] [Chemistry 69]

[0349]

[0350] [Chemistry 70]

[0351]

[0352] [Chemistry 71]

[0353]

[0354] [Chemistry 72]

[0355]

[0356] [Chemistry 73]

[0357]

[0358] In equation (B6-2), R fb1 and R fb2 Each hydrocarbon group consists independently of a fluorine atom or may contain heteroatoms and has 1 to 40 carbon atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as R in formula (B6-1-1). fa1 The same example represents a hydrocarbon group. R fb1 and R fb2 It should preferably be a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fb1 and R fb2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-N). - -SO2-CF2-) together form a ring, at which point R fb1 and R fb2 The groups formed by mutual bonding should preferably be fluorinated ethylidene or fluorinated propyleneide.

[0359] In equation (B6-3), R fc1 R fc2 and R fc3Each hydrocarbon group consists independently of a fluorine atom or may contain heteroatoms and has 1 to 40 carbon atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as R in formula (B6-1-1). fa1 The same example represents a hydrocarbon group. R fc1 R fc2 and R fc3 It should preferably be a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fc1 and R fc2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-C). - -SO2-CF2-) together form a ring, at which point R fc1 and R fc2 The groups formed by mutual bonding should preferably be fluorinated ethylidene or fluorinated propyleneide.

[0360] In equation (B6-4), R fd It can be a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as R in formula (B6-1-1). fa1 The same example represents hydrocarbon groups.

[0361] Specific examples of anions represented by formula (B6-4) are listed below, but are not limited thereto.

[0362] [Chemistry 74]

[0363]

[0364] [Chemistry 75]

[0365]

[0366] Examples of the aforementioned non-nucleophilic relative ions can also be cited as anions having aromatic rings substituted with iodine or bromine atoms. Specific examples of such anions can be exemplified by those represented by the following formula (B6-5).

[0367] [Chemistry 76]

[0368]

[0369] In equation (B6-5), x is 1, 2, or 3. y is 1, 2, 3, 4, or 5. z is 0, 1, 2, or 3. However, 1 ≤ y + z ≤ 5. y should preferably be 1, 2, or 3, with 2 or 3 being even better. z should preferably be 0, 1, or 2.

[0370] In equation (B6-5), X BIWhen x and / or y are 2 or more, they can be the same or different.

[0371] In formula (B6-5), L 11 It is a saturated hydrocarbon group with 1 to 6 carbon atoms, consisting of a single bond, ether bond, or ester bond, or may also contain ether or ester bonds. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic.

[0372] In formula (B6-5), L 12 When x is 1, it is a single bond or a divalent linker with 1 to 20 carbon atoms; when x is 2 or 3, it is a (x+1) valent linker with 1 to 20 carbon atoms, and the linker may also contain oxygen, sulfur or nitrogen atoms.

[0373] In equation (B6-5), R fe The carbon group may be a hydroxyl, carboxyl, fluorine, chlorine, bromine, or amino group, or may contain a fluorine, chlorine, bromine, hydroxyl, amino, or ether bond, and may be a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon oxy group having 1 to 20 carbon atoms, a hydrocarbon carbonyl group having 2 to 20 carbon atoms, a hydrocarbon oxycarbonyl group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyl oxy group having 1 to 20 carbon atoms, or -N(R) feA (R) feB ), -N(R feC )-C(=O)-R feD or -N(R) feC )-C(=O)-OR feD R feA and R feB Each can be independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R feC It is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms. R feD It is an aliphatic hydrocarbon group with 1 to 16 carbon atoms, an aryl group with 6 to 12 carbon atoms, or an aralkyl group with 7 to 15 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group with 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl oxy group with 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. The aforementioned hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyl group, hydrocarbon oxycarbonyl group, hydrocarbon carbonyl oxy group, and hydrocarbon sulfonyl oxy group can be straight-chain, branched, or cyclic. When x and / or z are 2 or more, each R fe They can be the same or different.

[0374] Among them, R fe It is advisable to use hydroxyl groups, -N(R) feC )-C(=O)-R feD-N(R) feC )-C(=O)-OR feD Fluorine atoms, chlorine atoms, bromine atoms, methyl groups, methoxy groups, etc.

[0375] In equation (B6-5), Rf 11 ~Rf 14 Each of these can be independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of them can be a fluorine atom or a trifluoromethyl group. Also, Rf 11 With Rf 12 They can also combine to form carbonyl groups. Rf 13 and Rf 14 All of them are fluorine atoms, which is of excellent quality.

[0376] Specific examples of anions represented by equation (B6-5) are shown below, but are not limited to these. Additionally, in the following equation, X... BI Same as above.

[0377] [Chemistry 77]

[0378]

[0379] [Chemistry 78]

[0380]

[0381] [Chemistry 79]

[0382]

[0383] [Chemistry 80]

[0384]

[0385] [Chemistry 81]

[0386]

[0387] [Chemistry 82]

[0388]

[0389] [Chemistry 83]

[0390]

[0391] [Chemistry 84]

[0392]

[0393] [Chemistry 85]

[0394]

[0395] [Chemistry 86]

[0396]

[0397] [Chemistry 87]

[0398]

[0399] [Chemistry 88]

[0400]

[0401] [Chemistry 89]

[0402]

[0403] [Chemistry 90]

[0404]

[0405] [Chemistry 91]

[0406]

[0407] [Chemistry 92]

[0408]

[0409] [Chemistry 93]

[0410]

[0411] [Chemistry 94]

[0412]

[0413] [Chemistry 95]

[0414]

[0415] [Chemistry 96]

[0416]

[0417] [Chemistry 97]

[0418]

[0419] [Chem. 98]

[0420]

[0421] [Chemistry 99]

[0422]

[0423] The aforementioned non-nucleophilic relative ions may also include the fluorobenzenesulfonate anion bonded to an aromatic group containing an iodine atom as described in Japanese Patent No. 6648726, the anion with a mechanism of decomposition due to acid as described in International Publication No. 2021 / 200056 and Japanese Patent Application Publication No. 2021-70692, the anion with a cyclic ether group as described in Japanese Patent Application Publication No. 2018-180525 and Japanese Patent Application Publication No. 2021-35935, and the anion as described in Japanese Patent Application Publication No. 2018-92159.

[0424] The aforementioned non-nucleophilic relative ions can also be further described in Japanese Patent Application Publication Nos. 2006-276759, 2015-117200, 2016-65016 and 2019-202974 as bulky benzenesulfonic acid derivatives without fluorine atoms, benzenesulfonate anions bonded to aromatic groups containing iodine atoms without fluorine atoms, and alkylsulfonate anions as described in Japanese Patent No. 6645464.

[0425] The aforementioned non-nucleophilic relative ions may further include the anions of disulfonic acid as described in Japanese Patent Application Publication No. 2015-206932, the anions of sulfonic acid on one side and sulfonamide or sulfonamide on the other side as described in International Publication No. 2020 / 158366, and the anions of sulfonic acid on one side and carboxylic acid on the other side as described in Japanese Patent Application Publication No. 2015-24989.

[0426] In equations (B7) and (B8), g1 and g2 are independently 0, 1, 2 or 3, and it is preferable to be 1.

[0427] In equation (B9), h1 is 0 or 1. h2 is 0, 1, 2, 3 or 4. h3 is 0, 1, 2, 3 or 4. However, when h1 is 0, 0 ≤ h2 + h3 ≤ 4, and when h1 is 1, 0 ≤ h2 + h3 ≤ 6.

[0428] In equations (B7), (B8) and (B9), L 1 The bonds can be single bonds, ether bonds, ester bonds, carbonyl bonds, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. From a synthetic point of view, ether bonds, ester bonds, and carbonyl bonds are preferred, with ester bonds and carbonyl bonds being even more desirable.

[0429] In equation (B7), Rf 1 and Rf 2 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among them, Rf 1 and Rf 2 To increase the acid strength of the produced acid, it is preferable that all atoms be fluorine atoms. Rf 3 and Rf 4Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among them, Rf is used to improve solvent solubility. 3 and Rf 4 At least one of them should be trifluoromethyl.

[0430] In equation (B8), Rf 5 and Rf 6 Each can be independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. However, all Rf 5 and Rf 6 They cannot all be hydrogen atoms simultaneously. Among them, Rf is used to improve solvent solubility. 5 and Rf 6 At least one of them should be trifluoromethyl.

[0431] In equation (B9), Rf 7 It is a fluorine atom, a fluorinated alkyl group having 1 to 6 carbon atoms, a fluorinated alkoxy group having 1 to 6 carbon atoms, or a fluorinated alkyl thio group having 1 to 6 carbon atoms. Rf 7 It is preferable to have a fluorine atom, trifluoromethyl, difluoromethyl, trifluoromethoxy, difluoromethoxy, trifluoromethylthio, or difluoromethylthio, with fluorine, trifluoromethyl, or trifluoromethoxy being more preferred. When h2 is 2, 3, or 4, each Rf 7 They can be the same or different.

[0432] In equation (B9), R 43 It is a hydrocarbon group with 1 to 20 carbon atoms other than fluorine atoms, or it may contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated in the description of formula (A) as R. 1 Examples of hydrocarbon groups are similar, but not limited to these. Also, when h3 is 2, 3, or 4, each R... 43 They can be the same or different.

[0433] Furthermore, when h3 is 2, 3, or 4, multiple R 43 They can also bond with each other and form rings together with the carbon atoms they are bonded to. Specific examples of rings formed in this case include: cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0434] Specific examples of the anion of repeating unit B7 can be listed below, but are not limited to these. Additionally, in the following formula, R... A As mentioned above, Me is a methyl group.

[0435] [Chemistry 100]

[0436]

[0437] [Chemistry 101]

[0438]

[0439] [Chemistry 102]

[0440]

[0441] [Chemistry 103]

[0442]

[0443] [Chemistry 104]

[0444]

[0445] [Chemistry 105]

[0446]

[0447] [Chemistry 106]

[0448]

[0449] [Chemistry 107]

[0450]

[0451] [Chemistry 108]

[0452]

[0453] [Chemistry 109]

[0454]

[0455] [Chemical 110]

[0456]

[0457] [Chemistry 111]

[0458]

[0459] [Chemistry 112]

[0460]

[0461] Specific examples of the anion of repeating unit B8 can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0462] [Chemistry 113]

[0463]

[0464] [Chemistry 114]

[0465]

[0466] [Chemistry 115]

[0467]

[0468] [Chemistry 116]

[0469]

[0470] [Chemistry 117]

[0471]

[0472] [Chemistry 118]

[0473]

[0474] [Chemistry 119]

[0475]

[0476] [Chemistry 120]

[0477]

[0478] [Chemistry 121]

[0479]

[0480] [Chemistry 122]

[0481]

[0482] [Chemistry 123]

[0483]

[0484] Specific examples of the anion of repeating unit B9 can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0485] [Chemistry 124]

[0486]

[0487] [Chemistry 125]

[0488]

[0489] [Chemistry 126]

[0490]

[0491] [Chemistry 127]

[0492]

[0493] [Chemistry 128]

[0494]

[0495] [Chemistry 129]

[0496]

[0497] [Chemistry 130]

[0498]

[0499] [Chemistry 131]

[0500]

[0501] [Chemistry 132]

[0502]

[0503] [Chemistry 133]

[0504]

[0505] [Chemistry 134]

[0506]

[0507] [Chemistry 135]

[0508]

[0509] [Chemistry 136]

[0510]

[0511] [Chemistry 137]

[0512]

[0513] [Chemistry 138]

[0514]

[0515] [Chemistry 139]

[0516]

[0517] [Chemistry 140]

[0518]

[0519] Specific examples of the anion of repeating unit B10 can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0520] [Chemistry 141]

[0521]

[0522] In equations (B7) to (B10), A + The aforementioned onium cation is preferably a sulfonium cation represented by formula (Z-1) or a sulfonium cation represented by formula (Z-2).

[0523] [Chemistry 142]

[0524]

[0525] In equations (Z-1) and (Z-2), R ct1 ~R ct5 Each is a hydrocarbon group with 1 to 30 carbon atoms, which may be independently composed of halogen atoms or may contain heteroatoms.

[0526] R ct1 ~R ct5 Specific examples of halogen atoms that can be represented include: fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc.

[0527] R ct1 ~R ct5The hydrocarbon group represented can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 30 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclohexenyl; aryl groups with 6 to 30 carbon atoms such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 30 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining these groups, which should preferably be aryl. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and some of the -CH2- in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0528] Also, R ct1 and R ct2 They can also bond to each other and form rings together with the sulfur atoms they are bonded to. Specific examples of the aforementioned ring structures can be shown in the following formulas, etc.

[0529] [Chemistry 143]

[0530]

[0531] In the formula, the dashed line represents R. ct3 Atomic bonds.

[0532] Specific examples of sulfonium cations represented by formula (Z-1) include those described in paragraphs

[0102] to

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

[0070] to

[0085] of Japanese Patent Application Publication No. 2023-169812, etc., but are not limited thereto.

[0533] Specific examples of citric acid represented by formula (Z-2) can be found in paragraph

[0181] of Japanese Patent Application Publication No. 2024-000259, but are not limited thereto.

[0534] Z + The onium cation represented should also be the sulfonium cation represented by the following formula (Z-3).

[0535] [Chemistry 144]

[0536]

[0537] In formula (Z-3), m1 is 0 or 1. When m1 is 0, it is a benzene ring; when m1 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with m1 = 0. m2 is 0 or 1. When m2 is 0, it is a benzene ring; when m2 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with m2 = 0. m3 is 0 or 1. When m3 is 0, it is a benzene ring; when m3 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with m3 = 0.

[0538] In formula (Z-3), m4 is 0, 1, 2, 3, or 4. The more iodine atoms in the cationic structure, the higher the absorption of EUV, but the solvent solubility will become poor and there is a concern about precipitation in the resist composition. Therefore, m4 should preferably be 0, 1, 2, or 3, with 0, 1, or 2 being better.

[0539] In formula (Z-3), m5 can be 0, 1, 2, 3, or 4. Considering the availability of raw materials, m5 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being more preferred. m6 can be 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, m6 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being more preferred. m7 can be 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, m7 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being more preferred.

[0540] In formula (Z-3), m8 is 0, 1, or 2. Considering the availability of raw materials, m8 should preferably be 0 or 1. m9 is 0, 1, or 2. Considering the availability of raw materials, m9 should preferably be 0 or 1. m10 is 0, 1, or 2. Considering the availability of raw materials, m10 should preferably be 0 or 1.

[0541] In formula (Z-3), m11 is 0 or 1. When m11 is 0, it is a benzene ring; when m11 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have a benzene ring with m11 of 0.

[0542] In formula (Z-3), m12 is 0, 1, 2, 3, or 4. The more iodine atoms in the cationic structure, the higher the absorption of EUV, but the solvent solubility will become poor and there is a concern about precipitation in the resist composition. Therefore, m12 should preferably be 0, 1, 2, or 3, with 0, 1, or 2 being better.

[0543] In equation (Z-3), m13 is 0, 1, or 2. From the perspective of raw material availability, m13 should preferably be 0 or 1. m14 is 0, 1, or 2. From a synthetic perspective, m14 should preferably be 0 or 1.

[0544] However, when m1 is 0, 0 ≤ m6 + m9 ≤ 4; when m1 is 1, 0 ≤ m6 + m9 ≤ 6. When m2 is 0, 0 ≤ m7 + m10 ≤ 4; when m2 is 1, 0 ≤ m7 + m10 ≤ 6. When m3 is 0, 1 ≤ m4 + m5 + m8 + m14 ≤ 4; when m3 is 1, 1 ≤ m4 + m5 + m8 + m14 ≤ 6. When m11 is 0, 0 ≤ m12 + m13 ≤ 4; when m11 is 1, 0 ≤ m12 + m13 ≤ 6. Also, m4 + m12 ≥ 1.

[0545] In equation (Z-3), R F1 ~R F3 Each R is independently a fluorine atom, a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among these, trifluoromethyl, trifluoromethoxy, and trifluorothiomethoxy are preferred. When m5 is 2 or more, each R... F1 They can be the same or different. When m6 is 2 or more, each R... F2 They can be the same or different. When m7 is 2 or more, each R... F3 They can be the same or different.

[0546] In equation (Z-3), R ct6 ~R ct9 The group can be a halogen atom other than iodine or fluorine, a nitro group, a cyano group, a hydrocarbon group with 1 to 20 carbon atoms (which may also contain heteroatoms), a hydrocarbon oxygen group with 1 to 20 carbon atoms (which may also contain heteroatoms), or a hydrocarbon thio group with 1 to 20 carbon atoms (which may also contain heteroatoms). The hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon thio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given and illustrated in the description of formula (A) as R. 1 The same example applies to the hydrocarbon group. Furthermore, some or all of the hydrogen atoms in the hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon sulfide group can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Also, a portion of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0547] Also, when m8 is 2, there are 2 Rs. ct6 They can be the same or different, and there are 2 Rs. ct6 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m9 is 2, there are 2 R atoms. ct7 They can be the same or different, and there are 2 Rs. ct7They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m10 is 2, the two R atoms... ct8 They can be the same or different, and there are 2 Rs. ct8 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m13 is 2, there are 2 R atoms. ct9 They can be the same or different, and there are 2 Rs. ct9 They can also bond with each other and form rings together with the carbon atoms they are bonded to. Specific examples of rings formed in this case include: cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0548] Furthermore, formula (Z-3) represents the S directly bonded to the sulfonium cation. + The aromatic rings can also bond with each other and with S + Together they form a ring. Specific examples of the aforementioned ring structure can be exemplified by the following formulas, etc.

[0549] [Chemistry 145]

[0550]

[0551] In the formula, the dashed lines represent atomic bonds.

[0552] In equation (Z-3), L B and L C These can be independently identified as single bonds, ether bonds, ester bonds, amide bonds, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Among them, L... B The bonds should ideally be single bonds, ether bonds, ester bonds, or sulfonate bonds, with ester bonds or sulfonate bonds being preferred. C It is preferable to have a single bond, ether bond, or ester bond, with a single bond being better.

[0553] In equation (Z-3), X L It is a single bond, or may contain heteroatoms, of carbon atoms ranging from 1 to 40. The aforementioned alkylene group can be linear, branched, or cyclic; specific examples include alkyldiyl, cyclic saturated alkylene groups, and arylene groups. Specific examples of the aforementioned heteroatoms include oxygen atoms, nitrogen atoms, and sulfur atoms.

[0554] X LExamples of hydrocarbon groups containing 1 to 40 carbon atoms that may also contain heteroatoms are shown below, but are not limited to these. Additionally, in the following formula, * indicates that they are related to L... B and L C Atomic bonds.

[0555] [Chemistry 146]

[0556]

[0557] [Chemistry 147]

[0558]

[0559] [Chemistry 148]

[0560]

[0561] [Chemistry 149]

[0562]

[0563] Among them, X is the most suitable. L -0~X L -22, X L -29~X L -34, and X L -47~X L -58.

[0564] The sulfonium cation represented by formula (Z-3) should preferably be represented by the following formula (Z-3-1).

[0565] [Chemistry 150]

[0566]

[0567] In the formula, m4~m10, m12~m14, R F1 ~R F3 R ct6 ~R ct9 L B L C and X L Same as above. The sulfonium cation represented by formula (Z-3-1) should preferably be represented by formula (Z-3-2).

[0568] [Chemistry 151]

[0569]

[0570] In the formula, m4~m10, R F1 ~R F3 and R ct6 ~R ct8 Same as above.

[0571] Specific examples of sulfonium cations represented by formula (Z-3) are shown below, but are not limited thereto. Additionally, in the following formula, Me is a methyl group.

[0572] [Chemistry 152]

[0573]

[0574] [Chemistry 153]

[0575]

[0576] [Chemistry 154]

[0577]

[0578] [Chemistry 155]

[0579]

[0580] [Chemistry 156]

[0581]

[0582] [Chemistry 157]

[0583]

[0584] [Chemistry 158]

[0585]

[0586] [Chemistry 159]

[0587]

[0588] [Chemistry 160]

[0589]

[0590] [Chemistry 161]

[0591]

[0592] [Chemistry 162]

[0593]

[0594] [Chemistry 163]

[0595]

[0596] [Chemistry 164]

[0597]

[0598] [Chemistry 165]

[0599]

[0600] [Chemistry 166]

[0601]

[0602] [Chemistry 167]

[0603]

[0604] [Chemistry 168]

[0605]

[0606] [Chemistry 169]

[0607]

[0608] [Chemistry 170]

[0609]

[0610] [Chemistry 171]

[0611]

[0612] [Chemistry 172]

[0613]

[0614] [Chemistry 173]

[0615]

[0616] [Chemistry 174]

[0617]

[0618] [Chemistry 175]

[0619]

[0620] [Chemistry 176]

[0621]

[0622] [Chemistry 177]

[0623]

[0624] [Chemistry 178]

[0625]

[0626] [Chemistry 179]

[0627]

[0628] The specific structures of repeating units B6 to B10 can be listed as any combination of the aforementioned anions and cations.

[0629] Repeating units B6 to B10 are units that generate acid due to irradiation with high-energy rays. It is believed that by incorporating these units into the polymer, acid diffusion can be appropriately suppressed, and a pattern with reduced LER can be obtained. Furthermore, it is believed that by incorporating these units into the polymer, the phenomenon of acid evaporating from the exposed areas and re-adhering to the unexposed areas during vacuum baking can be suppressed, and it is effective in reducing LER and reducing shape degradation caused by undesirable film loss in the unexposed areas.

[0630] Among the repeating units B6 to B10, considering the ideal units for processing blank photomasks, repeating units B7 to B10 are most suitable in terms of acid strength in suppressing acid diffusion and designing acid-unstable groups in polymers, with repeating units B8, B9, and B10 being even better.

[0631] The repeating units B6 to B10 are preferably introduced in the range of 0.1 to 30 mol%, and more preferably in the range of 0.5 to 20 mol%, in all the repeating units of the aforementioned polymer. Repeating units B6 to B10 may be used alone or in combination of two or more.

[0632] In all repeating units of the aforementioned polymer, the content of repeating units having an aromatic ring skeleton is preferably 65 mol% or more, more preferably 75 mol% or more, and even more preferably 85 mol% or more. When repeating units B6 to B10 are not present, it is preferable that all units have an aromatic ring skeleton.

[0633] The aforementioned polymers may also contain commonly used (meth)acrylate units protected by acid-labile groups, or (meth)acrylate units with close-knit groups such as lactone structures and hydroxyl groups other than phenolic hydroxyl groups. These repeating units can be used to fine-tune the properties of the resist film, but they may also be omitted.

[0634] Examples of (meth)acrylate units with binding groups mentioned above include: repeating units represented by formula (B11) (hereinafter also referred to as repeating unit B11), repeating units represented by formula (B12) (hereinafter also referred to as repeating unit B12), and repeating units represented by formula (B13) (hereinafter also referred to as repeating unit B13). These units do not exhibit acidity and can be used auxiliaryly as units to provide adhesion to the substrate and to adjust solubility.

[0635] [Chemistry 180]

[0636]

[0637] In equations (B11) to (B13), R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 51 It is -O- or methylene. R 52 It can be a hydrogen atom or a hydroxyl group. R 53 It is a saturated hydrocarbon group with 1 to 4 carbon atoms. i is 0, 1, 2 or 3.

[0638] When the polymer contains repeating units B11 to B13, their content should preferably be 0 to 20 mol% or more preferably 0 to 10 mol% of all repeating units in the aforementioned polymer. Repeating units B11 to B13 can be used alone or in combination of two or more.

[0639] The aforementioned polymers can be synthesized by copolymerizing monomers that require protection groups using known methods, followed by a deprotection reaction as needed. There are no particular limitations on the copolymerization reaction; free radical polymerization and anionic polymerization are preferred. These methods can be referenced in Japanese Patent Application Publication No. 2004-115630.

[0640] The weight-average molecular weight (Mw) of the aforementioned polymer is preferably between 1,000 and 50,000, and more preferably between 2,000 and 20,000. If Mw is above 1,000, there is no concern about the formation of rounded pattern heads leading to reduced resolution, or LER degradation, as is known. On the other hand, if Mw is below 50,000, there is no concern about LER degradation, especially when forming patterns with linewidths below 100 nm. Furthermore, in this invention, Mw is a polystyrene conversion value determined using gel permeation chromatography (GPC) with THF or DMF as solvent.

[0641] The molecular weight distribution (Mw / Mn) of the aforementioned polymer is 1.0–2.0, preferably 1.0–1.9, and a narrow dispersion of 1.0–1.8 is even better. With such a narrow dispersion, foreign matter will not be generated on the pattern after development, or the pattern shape will not deteriorate.

[0642] Furthermore, regarding the aforementioned basic polymer design, the dissolution rate of the alkaline developer should preferably be below 10 nm / min, more preferably below 7 nm / min, and even more preferably below 5 nm / min. In advanced generations, when the coating film applied to the substrate is in the thin film field (below 100 nm), the impact on pattern film loss during alkaline development becomes greater. When the alkaline dissolution rate of the polymer exceeds 10 nm / min, the pattern will break down, making it impossible to form fine patterns. This is particularly noticeable in the fabrication of photomasks requiring defect-free results, where there is a tendency for stronger development processes. In addition, in this invention, the dissolution rate of the basic polymer in the alkaline developer is calculated from the film loss obtained after spin-coating a polymer solution (polymer concentration: 16.7% by mass, solvent: propylene glycol monomethyl ether acetate (PGMEA)) onto an 8-inch silicon wafer, baking at 100°C for 90 seconds to form a 1000 nm thick film, and then developing it with a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution at 23°C for 100 seconds.

[0643] (B) The base polymer of the component may also contain other polymers besides those mentioned above. Other polymers may be base polymers known as components of resists. The content of other polymers is not particularly limited as long as it does not impair the effects of the invention.

[0644] [(C) Organic solvent]

[0645] The resist composition of the present invention may also contain an organic solvent as component (C). There are no particular limitations as long as the aforementioned organic solvent is capable of dissolving each component. Examples of such organic solvents include, for instance, ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone as described in paragraphs

[0144] to

[0145] of Japanese Patent Application Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; and propylene glycol monomethyl ether (PGME). Ethers such as 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 (EL), 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 γ-butyrolactone; and mixed solvents thereof. When using the acid-unstable groups of acetals, high-boiling-point alcohol solvents can be added to accelerate the deprotection reaction of the acetal. Specifically, diethylene glycol, propylene glycol, glycerol, 1,4-butanediol, and 1,3-butanediol can also be added.

[0646] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, PGME, cyclohexanone, EL, γ-butyrolactone, and their mixed solvents are preferred.

[0647] When the chemically amplified positive resist composition of the present invention contains (C) organic solvent, its content relative to 80 parts by mass of (B) base polymer is preferably 200 to 10,000 parts by mass, and more preferably 400 to 5,000 parts by mass. (C) organic solvent may be used alone or in combination with two or more types.

[0648] [(D) Photoacid generator]

[0649] The chemically amplified positive resist composition of the present invention may also contain a photoacid generator as component (D). There are no particular limitations on the aforementioned photoacid generator if it is a compound that generates acid upon irradiation by high-energy rays. Ideal photoacid generators include: sulfonium salts, sulfonium salts, sulfonyl diazomethanes, N-sulfonyloxyimides, oxime-O-sulfonate type acid generators, etc.

[0650] Specific examples of the aforementioned photoacid generators include: nonafluorobutane sulfonate, partially fluorinated sulfonates described in paragraphs

[0247] to

[0251] of Japanese Patent Application Publication No. 2012-189977, partially fluorinated sulfonates described in paragraphs

[0261] to

[0265] of Japanese Patent Application Publication No. 2013-101271, partially fluorinated sulfonates described in paragraphs

[0122] to

[0142] of Japanese Patent Application Publication No. 2008-111103, and those described in paragraphs

[0080] to

[0081] of Japanese Patent Application Publication No. 2010-215608. Among the aforementioned specific examples, the aromatic sulfonate type or alkane sulfonate type photoacid generators are more desirable because they generate an acid of appropriate strength when the acid-unstable group of the repeating unit B2 is deprotected.

[0651] Such photoacid generators are preferably salt compounds containing anions as shown below.

[0652] [Chemistry 181]

[0653]

[0654] [Chemistry 182]

[0655]

[0656] [Chemistry 183]

[0657]

[0658] [Chemistry 184]

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[0660] [Chemistry 185]

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[0691]

[0692] [Chemical Engineering 201]

[0693]

[0694] [Chemical Engineering 202]

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[0700] [Chemical Engineering 205]

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[0920] [Chemical 315]

[0921]

[0922] [Chemistry 316]

[0923]

[0924] [Chemistry 317]

[0925]

[0926] [Chemistry 318]

[0927]

[0928] [Chemistry 319]

[0929]

[0930] [Chem.320]

[0931]

[0932] [Chemistry 321]

[0933]

[0934] [Chemistry 322]

[0935]

[0936] [Chemistry 323]

[0937]

[0938] [Chemistry 324]

[0939]

[0940] [Chemistry 325]

[0941]

[0942] [Chemistry 326]

[0943]

[0944] [Chemistry 327]

[0945]

[0946] [Chemistry 328]

[0947]

[0948] [Chemistry 329]

[0949]

[0950] [Chemistry 330]

[0951]

[0952] [Chemistry 331]

[0953]

[0954] [Chemistry 332]

[0955]

[0956] [Chemistry 333]

[0957]

[0958] [Chemistry 334]

[0959]

[0960] [Chemistry 335]

[0961]

[0962] [Chemistry 336]

[0963]

[0964] [Chemistry 337]

[0965]

[0966] [Chemistry 338]

[0967]

[0968] [Chemistry 339]

[0969]

[0970] [Transformation 340]

[0971]

[0972] [Chemistry 341]

[0973]

[0974] [Chemistry 342]

[0975]

[0976] [Chemistry 343]

[0977]

[0978] [Chemistry 344]

[0979]

[0980] [Chemistry 345]

[0981]

[0982] [Chemistry 346]

[0983]

[0984] [Chemistry 347]

[0985]

[0986] [Chemistry 348]

[0987]

[0988] [Chemistry 349]

[0989]

[0990] [Chemical 350]

[0991]

[0992] [Chemistry 351]

[0993]

[0994] [Chemistry 352]

[0995]

[0996] [Chemistry 353]

[0997]

[0998] [Chemical formula 354]

[0999]

[1000] [Chemical formula 355]

[1001]

[1002] [Chemical formula 356]

[1003]

[1004] [Chemical formula 357]

[1005]

[1006] [Chemical formula 358]

[1007]

[1008] [Chemical formula 359]

[1009]

[1010] [Chemical formula 360]

[1011]

[1012] [Chemical formula 361]

[1013]

[1014] [Chemical formula 362]

[1015]

[1016] [Chemical formula 363]

[1017]

[1018] [Chemical formula 364]

[1019]

[1020] [Chemical formula 365]

[1021]

[1022] [Chemical formula 366]

[1023]

[1024] [Chemical formula 367]

[1025]

[1026] [Chem.368]

[1027]

[1028] [Chemistry 369]

[1029]

[1030] [Transformation 370]

[1031]

[1032] [Chemistry 371]

[1033]

[1034] [Chemistry 372]

[1035]

[1036] [Chemistry 373]

[1037]

[1038] [Chemistry 374]

[1039]

[1040] [Chemistry 375]

[1041]

[1042] [Chemistry 376]

[1043]

[1044] [Chemistry 377]

[1045]

[1046] [Chemistry 378]

[1047]

[1048] [Chemistry 379]

[1049]

[1050] [Chemistry 380]

[1051]

[1052] [Chemistry 381]

[1053]

[1054] [Chemistry 382]

[1055]

[1056] [Chemistry 383]

[1057]

[1058] [Chem. 384]

[1059]

[1060] [Chem.385]

[1061]

[1062] [Chemistry 386]

[1063]

[1064] [Chemistry 387]

[1065]

[1066] [Chem.388]

[1067]

[1068] [Chemistry 389]

[1069]

[1070] [Chemistry 390]

[1071]

[1072] [Chemistry 391]

[1073]

[1074] [Chemistry 392]

[1075]

[1076] [Chemistry 393]

[1077]

[1078] [Chem. 394]

[1079]

[1080] [Chemistry 395]

[1081]

[1082] [Chemistry 396]

[1083]

[1084] [Chemistry 397]

[1085]

[1086] [Chem.398]

[1087]

[1088] [Chemistry 399]

[1089]

[1090] [Chemical 400]

[1091]

[1092] [Chemical Engineering 401]

[1093]

[1094] [Chemical 402]

[1095]

[1096] [Chemical 403]

[1097]

[1098] [Chemical 404]

[1099]

[1100] [Chemical 405]

[1101]

[1102] [Chemical 406]

[1103]

[1104] [Chemical 407]

[1105]

[1106] [Chemical 408]

[1107]

[1108] [Chemical 409]

[1109]

[1110] [Chemical 410]

[1111]

[1112] [Chemistry 411]

[1113]

[1114] [Chemistry 412]

[1115]

[1116] [Chemistry 413]

[1117]

[1118] [Chemistry 414]

[1119]

[1120] [Chemical 415]

[1121]

[1122] [Chemistry 416]

[1123]

[1124] [Chemistry 417]

[1125]

[1126] [Chemistry 418]

[1127]

[1128] [Chemistry 419]

[1129]

[1130] [Chemistry 420]

[1131]

[1132] [Chemistry 421]

[1133]

[1134] [Chemistry 422]

[1135]

[1136] Furthermore, the aforementioned photoacid generator should also be a salt compound containing an anion represented by the following formula (D1).

[1137] [Chemistry 423]

[1138]

[1139] In equation (D1), p1 is 1, 2, or 3. p2 is 1, 2, 3, 4, or 5. p3 is 0, 1, 2, or 3. However, 1 ≤ p2 + p3 ≤ 5. q1 is 0 or 1.

[1140] In equation (D1), L 21 It can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond.

[1141] In equation (D1), L 22 It can be an ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond.

[1142] In equation (D1), L D When p1 is 1, it is a single bond or a hydrocarbon group with 1 to 20 carbon atoms; when p1 is 2 or 3, it is a (p1+1) valence hydrocarbon group with 1 to 20 carbon atoms. The hydrocarbon group and the (p1+1) valence hydrocarbon group may also contain at least one of the following: ether bond, carbonyl group, ester bond, amide bond, sulcinolone ring, lactam ring, carbonate bond, halogen atom, hydroxyl group and carboxyl group.

[1143] L D The alkylene groups representing carbons 1 to 20 can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl diyl groups with 1 to 20 carbon atoms, such as methane-diyl, 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, and dodecane-1,12-diyl; cyclic saturated alkylene groups with 3 to 20 carbon atoms, such as cyclopentane-diyl, cyclohexane-diyl, norcamphene-diyl, and adamantane-diyl; unsaturated aliphatic alkylene groups with 2 to 20 carbon atoms, such as vinylene and propylene-1,3-diyl; aryl groups with 6 to 20 carbon atoms, such as phenylene and naphthylene; and groups obtained by combining these. Also, L D The (p1+1) valence hydrocarbon group representing 1 to 20 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given by further removing one or two hydrogen atoms from the aforementioned examples of hydrocarbon groups representing 1 to 20 carbon atoms.

[1144] In equation (D1), Rf 21 and Rf 22Each is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl atom, but at least one of them is a fluorine atom or a trifluoromethyl atom.

[1145] In equation (D1), R 101 It can be a hydroxyl group, a carboxyl group, a saturated hydrocarbon group with 1 to 6 carbon atoms, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl oxygen group with 2 to 6 carbon atoms, a fluorine atom, a chlorine atom, a bromine atom, or a -N(R) group. 101A (R) 101B ), -N(R 101C )-C(=O)-R 101D or -N(R) 101C )-C(=O)-OR 101D R 101A and R 101B Each can be independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 101C It consists of a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 101D It is a saturated hydrocarbon group with 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group with 2 to 8 carbon atoms.

[1146] R 101 R 101A R 101B and R 101C The saturated hydrocarbon groups representing 1 to 6 carbon atoms can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, and n-hexyl; and cyclic saturated hydrocarbon groups with 3 to 6 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Also, R... 101 The saturated hydrocarbon base of the saturated hydrocarbon group representing carbon 1 to 6 can be given as examples as the specific examples of the aforementioned saturated hydrocarbon groups, R 101 The saturated hydrocarbon base of the carbonyl group representing 2 to 6 carbon atoms can be exemplified by the 1 to 5 carbon atoms in the specific examples of the aforementioned saturated hydrocarbon groups with 1 to 6 carbon atoms.

[1147] R 101D The unsaturated aliphatic hydrocarbon groups with 2 to 8 carbon atoms can be linear, branched, or cyclic. Specific examples include: alkenyl groups with 2 to 8 carbon atoms such as vinyl, propenyl, butenyl, and hexenyl; alkynyl groups with 2 to 8 carbon atoms such as ethynyl, propynyl, and butynyl; and cyclic unsaturated aliphatic hydrocarbon groups with 3 to 8 carbon atoms such as cyclohexenyl and norcamphenyl.

[1148] In equation (D1), R 102It is a saturated hydrocarbon group with 1 to 20 carbon atoms or an aryl group with 6 to 20 carbon atoms, and some or all of the hydrogen atoms of the saturated hydrocarbon group may be replaced by halogen atoms other than fluorine atoms, and some or all of the hydrogen atoms of the aryl group may be replaced by substituents selected from saturated hydrocarbon groups with 1 to 20 carbon atoms, saturated hydrocarbon oxygen groups with 1 to 20 carbon atoms, aryl groups with 6 to 20 carbon atoms, halogen atoms and hydroxyl groups.

[1149] R 102 The alkylene group representing 1 to 20 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as L. B The same example applies to alkylene groups representing carbon numbers from 1 to 20.

[1150] R 102 Specific examples of arylene groups with 6 to 20 carbon atoms include: phenylene, naphthylene, phenanthrenediyl, anthracenediyl, etc. The substituents of the aforementioned arylene groups, namely saturated hydrocarbon groups with 1 to 20 carbon atoms and hydrocarbon groups with 1 to 20 carbon atoms, can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 20 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, etc.; and cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, adamantyl, etc. Specific examples of the substituents of the aforementioned arylene groups, i.e., arylene groups with 6 to 14 carbon atoms, include: phenylene, naphthylene, phenanthrenediyl, anthracenediyl, etc.

[1151] The anion represented by formula (D1) should preferably be the anion represented by formula (D2).

[1152] [Chemistry 424]

[1153]

[1154] In equation (D2), p1, p2, p3, and L 21 L D and R 101 Same as above. q2 is 1, 2, 3, or 4. R 102A It can be a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxygen group with 1 to 20 carbon atoms, an aryl group with 6 to 14 carbon atoms, a halogen atom, or a hydroxyl group. Additionally, when q2 is 2, 3, or 4, each R... 102A They can be the same or different.

[1155] Specific examples of anions represented by formula (D1) are listed below, but are not limited to these.

[1156] [Chemical 425]

[1157]

[1158] [Chemistry 426]

[1159]

[1160] [Chemistry 427]

[1161]

[1162] [Chemistry 428]

[1163]

[1164] [Chemistry 429]

[1165]

[1166] [Chemistry 430]

[1167]

[1168] [Chemistry 431]

[1169]

[1170] [Chemistry 432]

[1171]

[1172] [Chemistry 433]

[1173]

[1174] [Chemistry 434]

[1175]

[1176] [Chemistry 435]

[1177]

[1178] [Chemistry 436]

[1179]

[1180] [Chemistry 437]

[1181]

[1182] [Chemistry 438]

[1183]

[1184] [Chemistry 439]

[1185]

[1186] [Chemistry 440]

[1187]

[1188] [Chemistry 441]

[1189]

[1190] [Chemistry 442]

[1191]

[1192] [Chemistry 443]

[1193]

[1194] [Chemistry 444]

[1195]

[1196] [Chemistry 445]

[1197]

[1198] [Chemistry 446]

[1199]

[1200] [Chemistry 447]

[1201]

[1202] [Chemistry 448]

[1203]

[1204] [Chemistry 449]

[1205]

[1206] [Chemistry 450]

[1207]

[1208] [Chemistry 451]

[1209]

[1210] [Chemistry 452]

[1211]

[1212] [Chemistry 453]

[1213]

[1214] [Chemistry 454]

[1215]

[1216] [Chemistry 455]

[1217]

[1218] [Chemistry 456]

[1219]

[1220] [Chemistry 457]

[1221]

[1222] [Chemistry 458]

[1223]

[1224] [Chemistry 459]

[1225]

[1226] [Chemistry 460]

[1227]

[1228] [Chemistry 461]

[1229]

[1230] (D) In ​​the photoacid generating agent, the cation paired with the aforementioned anion is preferably a sulfonium cation or a monazine cation. Specific examples of the aforementioned sulfonium cations can be listed and illustrated as examples of sulfonium cations represented by formulas (Z-1) and (Z-3), but are not limited thereto. Specific examples of the aforementioned monazine cations can be listed and illustrated as examples of monazine cations represented by formula (Z-2), but are not limited thereto.

[1231] The acid produced by the aforementioned photoacid generator should preferably have a pKa of -2.0 or higher, and preferably -1.0 or higher. Furthermore, the upper limit of the pKa should preferably be 2.0. Additionally, the pKa value is obtained using the pKa DB function in ACD / Chemsketch ver: 9.04, software manufactured by Advanced Chemistry Development, Inc.

[1232] When the chemically amplified positive resist composition of the present invention contains a (D) photoacid generator, its content is preferably 1 to 10 parts by mass, and more preferably 1 to 5 parts by mass, relative to 80 parts by mass of the aforementioned base polymer. By containing the (D) photoacid generator, the amount of acid generated in the exposed portion and the solubility inhibition of the unexposed portion can be appropriately adjusted. One type of (D) photoacid generator can be used alone, or two or more types can be used in combination.

[1233] When the chemically amplified positive resist composition of the present invention contains both (D) a photoacid generator and (A) a quencher, the content ratio of the photoacid generator to the quencher (photoacid generator / quencher), by mass ratio, is preferably less than 3, more preferably less than 2.5, and even more preferably less than 2. If the content ratio of the photoacid generator to the quencher in the aforementioned chemically amplified positive resist composition is within the aforementioned range, acid diffusion can be sufficiently suppressed, and excellent resolution and dimensional uniformity can be obtained.

[1234] [(E) Polymers containing fluorine atoms]

[1235] In order to achieve high contrast, suppress chemical flare of acids during high-energy ray irradiation, shield against acid mixing from the antistatic film during the coating of the antistatic film material onto the resist film, and suppress unintended pattern degradation, the chemically amplified positive resist composition of the present invention may also contain a fluorine-containing polymer as component (E). This fluorine-containing polymer contains at least one repeating unit selected from the following formulas: (E1), (E2), (E3), and (E4). The aforementioned fluorine-containing polymer also functions as a surfactant, thus preventing insoluble substances that may be generated during the development process from re-adhering to the substrate, thereby also effectively addressing development defects.

[1236] [Chemistry 462]

[1237]

[1238] In equations (E1) to (E4), k is 1, 2, or 3. B Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 201 R 202 R 204 and R 205 Each can be independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. R 203 R 206 R 207 and R208 Each of the following is independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-unstable group, and R 203 R 206 R 207 and R 208 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group can also be inserted between the carbon-carbon bonds. 1 It is a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms or a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms.

[1239] R 201 R 202 R 204 and R 205 The saturated hydrocarbon groups representing 1 to 10 carbon atoms can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 10 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; and cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, and norbornel. Among these, saturated hydrocarbon groups with 1 to 6 carbon atoms are preferred.

[1240] R 203 R 206 R 207 and R 208 The hydrocarbon group representing 1 to 15 carbon atoms can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 15 carbon atoms, alkenyl groups with 2 to 15 carbon atoms, and alkynyl groups with 2 to 15 carbon atoms, with alkyl groups having 1 to 15 carbon atoms being preferable. The aforementioned alkyl groups can include those listed above, as well as: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, etc. Furthermore, fluorinated hydrocarbon groups can be groups formed by replacing some or all of the hydrogen atoms of the carbon atoms bonded to the aforementioned hydrocarbon groups with fluorine atoms.

[1241] Z 1 The (k+1) valence hydrocarbon groups representing 1 to 20 carbon atoms can be exemplified by groups formed by further removing k hydrogen atoms from alkyl groups having 1 to 20 carbon atoms or cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms. Also, Z 1 The (k+1) valent fluorinated hydrocarbon groups representing carbon numbers from 1 to 20 can be groups formed by replacing at least one hydrogen atom of the aforementioned (k+1) valent hydrocarbon groups with a fluorine atom.

[1242] Specific examples of repeating units E1 to E4 can be listed below, but are not limited to these. Additionally, in the following formula, R... B Same as above.

[1243] [Chemistry 463]

[1244]

[1245] [Chemistry 464]

[1246]

[1247] [Chemistry 465]

[1248]

[1249] Furthermore, the aforementioned fluorine-containing polymer preferably contains at least one of the repeating units represented by the following formula (E5) (hereinafter also referred to as repeating unit E5) and the repeating units represented by the following formula (E6) (hereinafter also referred to as repeating unit E6).

[1250] [Chemistry 466]

[1251]

[1252] In equations (E5) and (E6), j1 is 1, 2, or 3. j2 is an integer satisfying 0 ≤ j2 ≤ 5 + 2(j3) - j1. j3 is 0 or 1. R C Each can be independently a hydrogen atom or a methyl group. R 209 A linear or branched hydrocarbon group with 1 to 5 carbon atoms, consisting of hydrogen atoms or groups containing heteroatoms inserted between carbon-carbon bonds. R 210 It can also be a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which heteroatoms are inserted between carbon-carbon bonds. R 211 It is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, and a portion of the -CH2- of the aforementioned saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. 2 It is a single bond, *-C(=O)-O- or *-C(=O)-NH-. Z 3 For single bonds, -O-, *-C(=O)-OZ 31 -Z 32 -or *-C(=O)-NH-Z 31 -Z 32 -. Z 31 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms. Z 32 These are single bonds, ester bonds, ether bonds, or sulfonamide bonds. * indicates an atomic bond with a carbon atom in the main chain.

[1253] R 209 and R 210Examples of hydrocarbon groups representing 1 to 5 carbon atoms include alkyl, alkenyl, and ynyl groups, with alkyl being preferred. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and n-pentyl. Furthermore, heteroatoms such as oxygen, sulfur, and nitrogen atoms can be inserted between the carbon-carbon bonds of the aforementioned hydrocarbon groups.

[1254] -OR in equation (E5) 209 It is preferable to have a hydrophilic group. In this case, R 209 It is advisable to use hydrogen atoms, or alkyl groups with 1 to 5 carbon atoms that have oxygen atoms inserted between carbon-carbon bonds.

[1255] R 211 The saturated hydrocarbon group with 1 to 20 carbon atoms, which is formed by replacing at least one hydrogen atom with a fluorine atom, can be any of the following: linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms or cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom.

[1256] Z 2 It should be *-C(=O)-O- or *-C(=O)-NH-. Additionally, R C It should be methyl. Through Z 2 The presence of a carbonyl group improves the ability of the antistatic membrane to capture acids. Also, R... C If the methyl group is used, it will become a rigid polymer with a higher glass transition temperature (Tg), thus inhibiting acid diffusion. This results in a resist film with good stability over time, and the resolution and pattern shape will not deteriorate.

[1257] Z 3 The saturated alkylene groups representing carbons 1 to 10 can be linear, branched, or cyclic. Specific examples include: methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, 1,1-dimethylethane-1,2-diyl, etc.

[1258] Repeating unit E5 can be listed as shown below, but is not limited to these. Additionally, in the following formula, R... C Same as above.

[1259] [Chemistry 467]

[1260]

[1261] [Chemistry 468]

[1262]

[1263] Repeating unit E6 can be listed as shown below, but is not limited to these. Additionally, in the following formula, R... C Same as above.

[1264] [Chemistry 469]

[1265]

[1266] [Chemistry 470]

[1267]

[1268] [Chemistry 471]

[1269]

[1270] [Chemistry 472]

[1271]

[1272] The content of repeating units E1 to E4 in the aforementioned polymer containing fluorine atoms is preferably 15 to 95 mol%, and more preferably 20 to 85 mol%. The content of repeating units E5 and / or E6 in the aforementioned polymer containing fluorine atoms is preferably 5 to 85 mol%, and more preferably 15 to 80 mol%. Repeating units E1 to E6 can be used alone or in combination of two or more.

[1273] (E) The polymer containing fluorine atoms may also contain other repeating units besides the aforementioned repeating units. Examples of such repeating units include those described in paragraphs

[0046] to

[0078] of Japanese Patent Application Publication No. 2014-177407. (E) When the polymer containing fluorine atoms contains other repeating units, their content in all the repeating units of the aforementioned polymer containing fluorine atoms should preferably be 50 mol% or less.

[1274] (E) Fluorine-containing polymers can be synthesized by copolymerizing monomers with protecting groups as needed using known methods, followed by deprotection reactions as required. There are no particular limitations on the copolymerization reaction; free radical polymerization and anionic polymerization are preferred. These methods can be found in Japanese Patent Application Publication No. 2004-115630.

[1275] (E) The Mw of the fluorine-containing polymer is preferably 2000–50000, and more preferably 3000–20000. If the Mw is above 2000, the acid will not diffuse, the resolution will not deteriorate, and the stability over time will not be compromised. If the Mw is below 50000, the solubility in the solvent is sufficient, and coating defects will not occur. Furthermore, the Mw / Mn ratio of the fluorine-containing polymer is preferably 1.0–2.2, and more preferably 1.0–1.7.

[1276] When the chemically amplified positive resist composition of the present invention contains a (E) fluorine-containing polymer, its content relative to 80 parts by mass of the (B) base polymer is preferably 0.01 to 30 parts by mass, and more preferably 0.1 to 20 parts by mass. The (E) fluorine-containing polymer can be used alone or in combination of two or more.

[1277] [(F) Other quenching agents]

[1278] The chemically amplified positive resist composition of the present invention may also contain a quencher other than component (A) (hereinafter also referred to as other quenchers) as component (F) as needed.

[1279] Other quenching agents mentioned above include known basic compounds. Known basic compounds include: primary, secondary, and tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds with carboxyl groups, nitrogen-containing compounds with sulfonyl groups, nitrogen-containing compounds with hydroxyl groups, nitrogen-containing compounds with hydroxyl phenyl groups, alcoholic nitrogen-containing compounds, amides, imides, carbamates, etc. In particular, primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Application Publication No. 2008-111103, amine compounds having hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, sulfonate bonds, or compounds having carbamate groups as described in Japanese Patent No. 3790649, are especially preferred. Ideal examples include: tris[2-(methoxymethoxy)ethyl]amine, tris[2-(methoxymethoxy)ethyl]amine-N-oxide, dibutylaminobenzoic acid, morpholine derivatives, imidazole derivatives, etc. By adding such basic compounds, the diffusion rate of acid in the resist film can be further suppressed, or the shape can be modified, for example.

[1280] Furthermore, other quenchers mentioned above include onium salts such as sulfonium salts, uranium salts, and ammonium salts of α-unfluorinated carboxylic acids, as described in Japanese Patent Application Publication No. 2008-158339. α-fluorinated sulfonic acids, imine acids, or methylated acids require deprotection of unstable acid groups, and through salt exchange with α-unfluorinated onium salts, α-unfluorinated carboxylic acids are released. Since α-unfluorinated carboxylic acids hardly undergo deprotection reactions, they function as quenchers.

[1281] Onium salts of carboxylic acids that are not fluorinated at the α-position can be listed as, for example, those represented by the following formula (F1).

[1282] [Chemistry 473]

[1283]

[1284] In equation (F1), R 301 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain hydrogen atoms or heteroatoms, but excludes those in which the hydrogen atom at the α-position of the carboxyl group is replaced by a fluorine atom or a fluoroalkyl group.

[1285] R 301 The hydrocarbon group represented can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, and other alkyl groups with 1 to 40 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6 Cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; alkenyl groups with 2 to 40 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated aliphatic hydrocarbon groups with 3 to 40 carbon atoms, such as cyclohexenyl; aryl groups with 6 to 40 carbon atoms, such as phenyl, naphthyl, alkylphenyl (2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butylphenyl, etc.), di- or trialkylphenyl (2,4-dimethylphenyl, 2,4,6-triisopropylphenyl, etc.), alkylnaphthyl (methylnaphthyl, ethylnaphthyl, etc.), and dialkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); and aralkyl groups with 7 to 40 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl.

[1286] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and some of the -CH2- in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, cyano groups, carbonyl groups, ether bonds, thioether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc. Examples of hydrocarbon groups containing heteroatoms include: thiophene group and other heteroaryl groups; alkoxyphenyl groups such as 4-hydroxyphenyl, 4-methoxyphenyl, 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 4-tert-butoxyphenyl, and 3-tert-butoxyphenyl; alkoxynaphthyl groups such as methoxynaphthyl, ethoxynaphthyl, n-propoxynaphthyl, and n-butoxynaphthyl; dialkoxynaphthyl groups such as dimethoxynaphthyl and diethoxynaphthyl; aryl-side alkyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl.

[1287] In equation (F1), Mq A + The cation is an onium cation. The aforementioned onium cation is preferably a sulfonium cation, a monazine cation, or an ammonium cation, with sulfonium or monazine cations being more preferred. Specific examples of the aforementioned sulfonium cation can be listed and illustrated as examples of the sulfonium cation represented by formula (Z-1) and formula (Z-3), and similar examples can be listed and illustrated as examples of the monazine cation represented by formula (Z-2).

[1288] The anions of onium salts represented by formula (F1) can be listed below, but are not limited to these.

[1289] [Chemistry 474]

[1290]

[1291] [Chemistry 475]

[1292]

[1293] [Chemistry 476]

[1294]

[1295] The aforementioned quenching agent can also ideally be a sulfonium salt of a carboxylic acid containing an iodinated benzene ring, represented by the formula (F2).

[1296] [Chemistry 477]

[1297]

[1298] In equation (F2), s is 1, 2, 3, 4, or 5. t is 0, 1, 2, or 3. However, 1 ≤ s + t ≤ 5. u is 1, 2, or 3.

[1299] In equation (F2), R 311 The hydroxyl, fluorine, chlorine, bromine, amino, nitro, cyano, or hydrogen atom may be partially or wholly substituted by a halogen atom, and may be a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 6 carbon atoms, or a saturated hydrocarbon sulfonyl oxy group having 1 to 4 carbon atoms, or -N(R 311A )-C(=O)-R 311B or -N(R) 311A )-C(=O)-OR 311B R 311A It consists of a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 311B It is a saturated hydrocarbon group with 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group with 2 to 8 carbon atoms. When t and / or u is 2 or more, each R 311 They can be the same or different.

[1300] In formula (F2), L 21 It is a single bond or a (u+1) valence linking group having 1 to 20 carbon atoms, and may also contain at least one selected from ether bonds, carbonyl groups, ester bonds, amide bonds, sulfonyl lactone rings, lactam rings, carbonate bonds, halogen atoms, hydroxyl groups, and carboxyl groups. The aforementioned saturated hydrocarbon groups, saturated hydrocarbon oxy groups, saturated hydrocarbon carbonyl oxy groups, and saturated hydrocarbon sulfonyl oxy groups may be linear, branched, or cyclic.

[1301] In equation (F2), R 312 R 313 and R 314 Each hydrocarbon group consists independently of a halogen atom or may contain heteroatoms and has 1 to 20 carbon atoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, alkenyl groups with 2 to 20 carbon atoms, aryl groups with 6 to 20 carbon atoms, and aralkyl groups with 7 to 20 carbon atoms. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by hydroxyl, carboxyl, halogen, oxo, cyano, nitro, sulfonyl lactone ring, sulfonyl, or sulfonium salt-containing groups, and part of the -CH2- group in the aforementioned hydrocarbon group may be replaced by ether, ester, carbonyl, amide, carbonate, or sulfonate bonds. Also, R... 312 and R 313 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[1302] Specific examples of compounds represented by formula (F2) can be found in Japanese Patent Application Publication No. 2017-219836. Compounds represented by formula (F2) have high sensitization effects due to their high absorption and also have high acid diffusion control effects.

[1303] The aforementioned quenching agent may also be a nitrogen-containing carboxylate compound represented by the following formula (F3).

[1304] [Chemistry 478]

[1305]

[1306] In equation (F3), R 321 ~R 324 Each is independently a hydrogen atom, -L 31 -CO2 - It may also contain hydrocarbon groups with 1 to 20 carbon atoms, or heteroatoms. R 321 With R 322 R 322 With R 323 、or R 323 With R 324 They can also bond to each other and form rings together with the carbon atoms they are bonded to. 31 It is a single bond or may contain heteroatoms and is a hydrocarbon group with 1 to 20 carbon atoms. R 325 It consists of a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms.

[1307] In equation (F3), ring R r It is a ring containing carbon atoms and nitrogen atoms of 2 to 6 carbons, and some or all of the hydrogen atoms of the carbon atoms bonded to the ring may be replaced by hydrocarbon groups of 1 to 20 carbons, or -L 31 -CO2 - The ring may be substituted, and a portion of the carbon atom in the ring may be replaced by a sulfur atom, an oxygen atom, or a nitrogen atom. The aforementioned ring may be an alicyclic or aromatic ring, and preferably a 5-membered or 6-membered ring. Specific examples include: pyridine ring, pyrrole ring, pyrrolidine ring, piperidine ring, pyrazole ring, imidazoline ring, pyridazine ring, pyrimidine ring, pyrazine ring, imidazoline ring, oxazole ring, thiazole ring, morpholine ring, thiazine ring, triazole ring, etc.

[1308] The carboxylic acid salt represented by formula (F3) has at least one -L 31 -CO2- group. That is, R 321 ~R 324 At least one of them is -L 31 -CO2- and / or bonded to ring R r At least one of the hydrogen atoms in the carbon atom is -L 31 -CO2- substitution.

[1309] In equation (F3), Mq B +Examples of sulfonium cations, monazine cations, or ammonium cations may be listed, with sulfonium cations being preferred. Specific examples of the aforementioned sulfonium cations may be listed and illustrated as examples of sulfonium cations represented by formula (Z-1) and sulfonium cations represented by formula (Z-3), or similar examples.

[1310] The anions of compounds represented by formula (F3) can be listed below, but are not limited to these.

[1311] [Chemistry 479]

[1312]

[1313] [Chemistry 480]

[1314]

[1315] [Chemistry 481]

[1316]

[1317] [Chemistry 482]

[1318]

[1319] [Chemistry 483]

[1320]

[1321] [Chemistry 484]

[1322]

[1323] Furthermore, the aforementioned quenching agents can also be betaine-type compounds of weak acids. Specific examples are listed below, but are not limited to these.

[1324] [Chemistry 485]

[1325]

[1326] The aforementioned quenchers can be further exemplified by polymer-type quenchers described in Japanese Patent Application Publication No. 2008-239918. These quenchers improve the rectangularity of the resist pattern by aligning to the surface of the resist film. Polymer-type quenchers also prevent film loss and dome-shaped formation of the pattern when using protective films for immersion exposure.

[1327] When the chemically amplified positive resist composition of the present invention contains other quenchers (F), their content relative to 80 parts by weight of the aforementioned base polymer (B) is preferably 0 to 50 parts by weight, and more preferably 0.1 to 40 parts by weight. The aforementioned quenchers can be used alone or in combination of two or more.

[1328] [(G) surfactant]

[1329] In the chemically amplified positive resist composition of the present invention, a conventional surfactant as component (G) may be included to improve the coating properties to the substrate. Many such surfactants are known, as described in International Publication No. 2006 / 121096, Japanese Patent Application Publication No. 2008-102383, Japanese Patent Application Publication No. 2008-304590, Japanese Patent Application Publication No. 2004-115630, and Japanese Patent Application Publication No. 2005-8766, and can be selected by referring to them.

[1330] When the chemically amplified positive resist composition of the present invention contains (G) surfactant, its content relative to 80 parts by mass of (B) base polymer is preferably 2 parts by mass or less, more preferably 1 part by mass or less, and the lower limit is preferably 0.01 parts by mass or more. (G) surfactant can be used alone or in combination of two or more.

[1331] [Resist Pattern Formation Method]

[1332] The resist pattern forming method of the present invention includes the following steps:

[1333] A resist film is formed on a substrate using the aforementioned chemically amplified positive resist composition.

[1334] The aforementioned resist film was exposed using high-energy rays, and

[1335] The resist pattern is obtained by developing the resist film that has been irradiated with the aforementioned pattern using an alkaline developer.

[1336] The aforementioned substrate can be, for example, substrates used in integrated circuit manufacturing (Si, SiO, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective films, etc.) or substrates used in mask circuit manufacturing (Cr, CrO, CrON, MoSi2, Si, SiO, SiO2, etc.). The aforementioned chemically amplified positive resist composition is coated onto the aforementioned substrate using methods such as spin coating to achieve a film thickness of 0.03–2 μm. The substrate is then pre-baked on a hot plate, preferably at 60–150°C for 1–20 minutes, and more preferably at 80–140°C for 1–10 minutes, to form a resist film.

[1337] Then, the aforementioned resist film is exposed to high-energy rays to irradiate the pattern. Examples of such high-energy rays include: ultraviolet rays, far-ultraviolet rays, excimer lasers (KrF, ArF, etc.), EB, EUV, X-rays, gamma rays, synchrotron radiation, etc.

[1338] When using ultraviolet light, far ultraviolet light, excimer lasers, EUV, X-rays, gamma rays, or synchrotron radiation to generate high-energy rays, a mask is used to form the desired pattern, and the exposure dose should preferably be 1–300 mJ / cm². 2 And preferably, it should be 10–200 mJ / cm 2 Irradiation should be carried out in a manner that allows for exposure. When using EB (exposed radiation) for high-energy rays, the exposure dose should ideally be 1–300 μC / cm. 2 And preferably, it should be 10–200 μC / cm 2 The process involves direct depiction. Furthermore, the chemically amplified positive resist composition of this invention is particularly useful in EUV or EB lithography.

[1339] In addition to the usual exposure methods, the immersion method, in which a liquid is inserted between the mask and the resist film, can also be used, depending on the situation. In this case, a water-insoluble protective film can also be used.

[1340] Then, perform post-exposure baking (PEB) on a heating plate, preferably at 60–150°C for 1–20 minutes and more preferably at 80–140°C for 1–10 minutes.

[1341] Subsequently, a developer solution containing an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH) of 0.1 to 5% by mass, and more preferably 2 to 3% by mass, is used to develop the substrate for 0.1 to 3 minutes, preferably 0.5 to 2 minutes, using common methods such as dip, immersion, or spray, thereby forming the desired pattern on the substrate.

[1342] The chemically amplified positive resist composition of the present invention is useful when particularly high etch resistance is required, and when the pattern linewidth variation and LER remain small even when the time from exposure to PEB is prolonged. Furthermore, the resist composition of the present invention is particularly useful when the surface of the substrate is made of a material that is prone to pattern peeling or pattern breakage due to difficulty in achieving good adhesion of the resist pattern. Examples of such substrates include substrates formed by sputtering metallic chromium or chromium compounds containing one or more light elements selected from oxygen, nitrogen, and carbon. The chemically amplified positive resist composition of the present invention is particularly useful for pattern formation using a blank photomask as the substrate.

[1343] Example

[1344] The present invention will be specifically described below with examples of synthesis, embodiments, and comparative examples, but the present invention is not limited to the following embodiments. Furthermore, the apparatus used is described below.

[1345] • MALDITOF-MS: S3000 manufactured by Nippon Electronics Co., Ltd.

[1346] [1] Synthesis of sulfonium salts

[1347] [Example 1-1] Synthesis of Sulfonium Salt SQ-1

[1348] [Chemistry 486]

[1349]

[1350] (1) Synthesis of intermediate In-1

[1351] Under nitrogen atmosphere, 4-iodophenol (110.0 g), methyl thiosalicylate (92.5 g), and copper iodide (9.5 g) were dissolved in N-methylpyrrolidone (400 g) in a reaction vessel. The temperature inside the reaction vessel was raised to 70 °C, and triethylamine (65.8 g) was added dropwise. After the addition, the reaction vessel was heated to 80 °C and matured for 12 hours. After maturation, the reaction solution was cooled, and water (300 g) was added to stop the reaction. The target was extracted with toluene (500 g). After extraction, a conventional aqueous work-up was performed, and the solvent was distilled off. The solution was then purified by distillation to obtain 113.2 g of intermediate In-2 (87% yield) as an oil.

[1352] (2) Synthesis of intermediate In-2

[1353] Under nitrogen atmosphere, intermediate In-1 (113.2 g), potassium carbonate (72.1 g), and sodium iodide (6.5 g) were dissolved in DMF (400 g) in a reaction vessel. The temperature inside the reaction vessel was raised to 70 °C, and 1-bromooctane (100.8 g) was added dropwise. After addition, the reaction vessel was heated to 80 °C and matured for 12 hours. After maturation, the reaction solution was cooled, and water (500 g) was added to stop the reaction. The target was extracted with hexane (500 g). Subsequently, aqueous work-up was performed, and the solvent was distilled off. The solution was then purified by silica gel column chromatography to obtain 153.9 g of intermediate In-2 (95% yield) as an oil.

[1354] (3) Synthesis of intermediate In-3

[1355] Under nitrogen atmosphere, intermediate In-2 (37.3 g) and diphenylmonazine methanesulfonate (41.4 g) were dissolved in anisole (150 g) in a reaction vessel. Copper acetate (0.9 g) was then added, and the temperature in the reaction vessel was raised to 100 °C for heating and maturation for 12 hours. After maturation, the reaction solution was cooled, and water (200 g) was added to stop the reaction. The target was extracted with dichloromethane (300 g). Subsequently, a standard aqueous work-up was performed, and the solvent was distilled off. The solution was then purified using a silica gel column to obtain 47.4 g of intermediate In-3 as an oil (87% yield).

[1356] (4) Synthesis of sulfonium salt SQ-1

[1357] Under nitrogen atmosphere, intermediate In-3 (16.3 g) was dissolved in methanol (40 g) in a reaction vessel. A 25% (w / w) aqueous solution of sodium hydroxide (5.8 g) was added, and the mixture was allowed to mature for 4 hours. After maturation, water (30 g) was added to stop the reaction, and dichloromethane (80 g) was added to extract the target. Subsequently, a standard aqueous work-up was performed, and the solvent was distilled off. The residue was then washed with diisopropyl ether to obtain 11.3 g of SQ-1 (87% yield) as the target in an oily form.

[1358] The TOF-MS results of SQ-1 are shown below.

[1359] MALDI TOF-MS:POSITIVE M + 435 (equivalent to C) 27 H 31 O3S + )

[1360] [Examples 1-2 to 1-10] Synthesis of Sulfonium Salts SQ-2 to SQ-10

[1361] Using the corresponding raw materials and known organic synthesis reactions, sulfonium salts SQ-2 to SQ-10 represented by the following formulas were synthesized.

[1362] [Chemistry 487]

[1363]

[1364] [2] Synthesis of basic polymers

[1365] [Synthetic Example] Synthesis of basic polymers (P-1 to P-6)

[1366] The monomers were combined using a known formulation and copolymerized in a solvent. The reaction solution was then added to hexane, and the precipitated solid was washed with hexane, separated, and dried to obtain a basic polymer (P-1 to P-6) with the composition shown below. The composition of the obtained basic polymer was utilized... 1 H-NMR, 13 The results were confirmed by C-NMR, and Mw and Mw / Mn were confirmed using GPC (solvent: DMF, standard: polystyrene).

[1367] [Chemistry 488]

[1368]

[1369] [3] Preparation of chemically amplified positive resist composition

[1370] [Examples 2-1 to 2-50, Comparative Examples 1-1 to 1-35]

[1371] The components were dissolved in an organic solvent according to the compositions shown in Tables 1-3 below, and the resulting solutions were filtered through a 5 nm nylon filter and a 1 nm UPE filter to obtain a chemically amplified positive resist composition. The aforementioned organic solvent was a mixture of 940 parts by mass of PGMEA, 1870 parts by mass of EL, and 1870 parts by mass of PGME.

[1372] [Table 1]

[1373]

[1374] [Table 2]

[1375]

[1376] [Table 3]

[1377]

[1378] In Tables 1 to 3, the photoacid generators PAG-1 to PAG-6, the comparative quenchers SQ-A to SQ-D, and the fluorine-containing polymers FP-1 to FP-5 are described below.

[1379] [Chemistry 489]

[1380]

[1381] [Chemistry 490]

[1382]

[1383] [Chemistry 491]

[1384]

[1385] [4] Evaluation of EB lithography

[1386] [Examples 3-1 to 3-50, Comparative Examples 2-1 to 2-35]

[1387] Various chemically amplified positive resist compositions (R-1 to R-50, CR-1 to CR-35) were spin-coated onto a 152 mm square EUV exposure mask with a chromium compound outermost surface using an ACT-M spin coater. The mask was then pre-baked at 110°C for 600 seconds on a heated plate to obtain a resist film with a thickness of 80 nm. The thickness of the obtained resist film was measured using an optical measuring instrument, NANOSPEC (Nanometrics). Measurements were taken at 81 positions within the plane of the blank substrate, excluding the outer 10 mm from the periphery, to determine the average thickness and thickness range.

[1388] Then, exposure was performed using an electron beam exposure apparatus (EBM-5000plus manufactured by NuFlare Technology Co., Ltd., with an accelerating voltage of 50kV), with PEB applied at 110°C for 600 seconds, and development was carried out with a 2.38% by mass TMAH aqueous solution to obtain a positive pattern.

[1389] The obtained resist pattern was evaluated as follows. The patterned blank mask was observed using overhead SEM (scanning electron microscope). The optimal exposure (μC / cm²) was defined as the exposure at a 1:1 line-to-space (LS) resolution of 200 nm. 2 The minimum size at which the line-to-line spacing (LS) at a 200 nm resolution is determined by exposure at a 1:1 ratio is defined as the resolution (limit resolution). The LER (Leadership Reduction) of the 200 nm LS is then measured using SEM. For the limit resolution of the isolation spacing (IS), the minimum size at which the line-to-line spacing (LS) at a 9:1 ratio is determined by exposure at a 9:1 ratio is defined as the limit resolution. The pattern shape is visually assessed to determine if it is rectangular. The results are shown in Tables 4-6.

[1390] [Table 4]

[1391]

[1392] [Table 5]

[1393]

[1394] [Table 6]

[1395]

[1396] As shown in Tables 4-6, the chemically amplified positive resist compositions (R-1 to R-50) of the present invention all exhibit good resolution, LER, and pattern rectangularity. On the other hand, the resist compositions of the comparative examples (CR-1 to CR-35) have insufficient optimization for acid diffusion, and deterioration in resolution, LER, and pattern rectangularity was observed.

[1397] The resist patterning method using the chemically amplified positive resist composition of the present invention is useful in the manufacture of semiconductor devices, especially in the optical lithography of transmissive and reflective blank photomasks.

Claims

1. A matte salt, represented by the following formula (A); In the formula, n1 is 0 or 1; n2 is 0, 1, 2, 3 or 4; n3 is 0 or 1; n4 is 0, 1, 2, 3 or 4; L A It can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond, or carbamate bond; R alk It is an alkyl group having 6 to 18 carbon atoms or a fluorinated alkyl group having 4 to 18 carbon atoms; R alk When it is an alkyl group having 6 to 18 carbon atoms, the alkyl group has at least one straight-chain structure with 6 or more carbon atoms; R alk When the fluorinated alkyl group has 4 to 18 carbon atoms, the fluorinated alkyl group has at least two groups selected from -CF2- and -CF3; furthermore, a portion of the -CH2- of the alkyl group and the fluorinated alkyl group may also be replaced by an ether bond or a carbonyl group, and the alkyl group and the fluorinated alkyl group may also contain a ring structure selected from cyclopentane ring, cyclohexane ring, adamantane ring, norcamphenic ring and benzene ring at the end or between carbon-carbon bonds; R a It is a hydrocarbon group with 1 to 30 carbon atoms, which may contain halogen atoms or heteroatoms; also, R a and the bonded S in the formula + Two of the two aromatic rings can also bond to each other and form a ring together with the sulfur atoms they are bonded to; R 1 It can be a halogen atom, nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms; when n2 is 2, 3 or 4, each R 1 They can be the same or different, and there are multiple Rs. 1 They can also bond to each other and form rings together with the carbon atoms they are bonded to; R 2 It can be a halogen atom, nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms; when n4 is 2, 3 or 4, each R 2 They can be the same or different, and there are multiple Rs. 2 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

2. The matte salt according to claim 1, wherein it is represented by the following formula (A1); In the formula, n1~n4, L A R alk R a R 1 and R 2 Same as above; n5 is 0 or 1; n6 is 0, 1, 2, 3 or 4; R 3 It can be a halogen atom, nitro group, cyano group, hydroxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms; when n6 is 2, 3 or 4, each R 3 They can be the same or different, and there are multiple Rs. 3 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

3. The matte salt according to claim 2, wherein it is represented by the following formula (A2); In the formula, n2, n4, n6, L A R alk R a R 1 R 2 and R 3 Same as above.

4. A quenching agent comprising the sulfite salt according to claim 1.

5. A chemically amplified positive resist composition comprising the quencher according to claim 4.

6. The chemically amplified positive resist composition according to claim 5 further comprises a base polymer containing a polymer that decomposes due to the action of acid and increases its solubility in alkaline developer.

7. The chemically amplified positive resist composition according to claim 6, wherein, The polymer contains repeating units represented by the following formula (B1); In the formula, a1 is 0 or 1; a2 is 0, 1 or 2; a3 is an integer that satisfies 0≤a3≤5+2(a2)-a4; a4 is 1, 2 or 3; R A It consists of hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups; R 11 It can be a halogen atom, a nitro group, a carboxyl group, a saturated hydrocarbon group with 1 to 6 carbons that can also be replaced by a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbons that can also be replaced by a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbons that can also be replaced by a halogen atom. A 1 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

8. The chemically amplified positive resist composition according to claim 6, wherein, The polymer contains repeating units represented by the following formula (B2-1); In the formula, R A It consists of hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups; b1 is 0 or 1; b2 is 0, 1 or 2; b3 is an integer satisfying 0 ≤ b3 ≤ 5 + 2(b2) - b4; b4 is 1, 2 or 3; b5 is 0 or 1; R 21 It is a halogen atom, or a saturated hydrocarbon group having 1 to 6 carbons that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl group having 1 to 6 carbons that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl group having 2 to 8 carbons that can be substituted by a halogen atom. A 2 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-; X is an acid-labile group when b4 is 1, and is a hydrogen atom or an acid-labile group when b4 is 2 or 3, but at least one of them is an acid-labile group.

9. The chemically amplified positive resist composition according to claim 6, wherein, The polymer contains repeating units represented by the following formula (B2-2); In the formula, c1 is 0, 1, or 2; c2 is 0, 1, or 2; c3 is 0, 1, 2, 3, 4, or 5; c4 is 0, 1, or 2. R A It consists of hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups; R 22 and R 23 Each can be independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms, and R 22 and R 23 They can also bond to each other and form rings together with the carbon atoms they are bonded to; R 24 Each is independently a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkoxy group having 1 to 5 carbon atoms; R 25 Each can be an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms; A 3 It is a single bond, phenylene, naphthylene, or *-C(=O)-OA 31 -;A 31 It may also contain hydroxyl groups, ether bonds, ester bonds, or lactone rings, and be an aliphatic alkylene group with 1 to 20 carbon atoms, or a phenylene or naphthylene group; * represents the atomic bond between the main chain and the carbon atom.

10. The chemically amplified positive resist composition according to claim 6, wherein, The polymer contains at least one repeating unit selected from the repeating unit represented by formula (B3), the repeating unit represented by formula (B4), and the repeating unit represented by formula (B5); In the formula, d is 0, 1, 2, 3, 4, 5 or 6; e is 0, 1, 2, 3 or 4; f1 is 0 or 1; f2 is 0, 1 or 2; f3 is 0, 1, 2, 3, 4 or 5; R A It consists of hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups; R 31 and R 32 They are, independently, a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 6 carbons that can be substituted by a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbons that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbons that can be substituted by a halogen atom. R 33 It can be a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxygen group with 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms, a saturated hydrocarbon oxy hydrocarbon group with 2 to 20 carbon atoms, a saturated hydrocarbon thio hydrocarbon group with 2 to 20 carbon atoms, a halogen atom, a nitro group, or a cyano group, and can also be a hydroxyl group when f2 is 1 or 2. A 4 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

11. The chemically amplified positive resist composition according to claim 6, wherein, The polymer contains at least one of the repeating units represented by formula (B6), formula (B7), formula (B8), formula (B9), and formula (B10). In the formula, g1 and g2 are independently 0, 1, 2 or 3 respectively; h1 is 0 or 1; h2 is 0, 1, 2, 3 or 4; h3 is 0, 1, 2, 3 or 4; however, when h1 is 0, 0≤h2+h3≤4, and when h1 is 1, 0≤h2+h3≤6; R A Each can be independently composed of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; Z 1 It is a single bond or may have substituents; Z 2 For single bonds, **-C(=O)-OZ 21 -、**-C(=O)-NH-Z 21 -or**-OZ 21 -;Z 21 It is an aliphatic alkylene group, phenylene group, or a divalent group obtained by combining them with 1 to 6 carbon atoms, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds or hydroxyl groups; Z 3 It can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Z 4 It is a single bond, or an aliphatic alkylene group with 1 to 6 carbon atoms, a phenylene group, or a divalent group obtained by combining them, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups; Z 5 Each can be a single bond, or may have substituents such as phenylene, naphthylene, or *-C(=O)-OZ. 51 -;Z 51 It is an aliphatic alkylene group, phenylene group, or naphthylene group with 1 to 10 carbon atoms, and the aliphatic alkylene group may also contain a halogen atom, hydroxyl group, ether bond, ester bond, or lactone ring; Z 6 It can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Z 7 Each is independently a single bond, ***-Z 71 -C(=O)-O-、***-C(=O)-NH-Z 71 -or ***-OZ 71 -;Z 71 It may also contain a hydrocarbon group with 1 to 20 carbon atoms; Z 8 Each is independently a single bond, ****-Z 81 -C(=O)-O-、****-C(=O)-NH-Z 81 -or ****-OZ 81 -;Z 81 It may also contain a hydrocarbon group with 1 to 20 carbon atoms; Z 9 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, *-C(=O)-OZ 91 -、*-C(=O)-N(H)-Z 91 -or *-OZ 91 -;Z 91 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group; * indicates an atomic bond with a carbon atom in the main chain; ** indicates an atomic bond with a Z atom. 1 atomic bonds; *** indicates and Z 6 atomic bonds; **** represents the bond between Z and Z. 7 atomic bonds; L 1 It can be a single bond, ether bond, ester bond, carbonyl group, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Rf 1 and Rf 2 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; Rf 3 and Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; Rf 5 and Rf 6 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; however, all Rf 5 and Rf 6 It cannot be both hydrogen atoms at the same time; Rf 7 It is a fluorine atom, a fluorinated alkyl group having 1 to 6 carbon atoms, a fluorinated alkoxy group having 1 to 6 carbon atoms, or a fluorinated alkyl thio group having 1 to 6 carbon atoms; R 41 and R 42 Each can be independently a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms; also, R 41 and R 42 They can also bond to each other and form rings together with the sulfur atoms they are bonded to; R 43 It can be a halogen atom other than fluorine, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; when h3 is 2, 3 or 4, each R 43 They can be the same or different, and there are multiple Rs. 43 They can also bond to each other and form rings together with the carbon atoms they are bonded to; M - It is a non-nucleophilic relative ion; A + It is a ium cation.

12. The chemically amplified positive resist composition according to claim 6, wherein, Of all the repeating units in the base polymer, the content of repeating units with an aromatic ring skeleton is 60 mol% or more.

13. The chemically amplified positive resist composition according to claim 5 further contains an organic solvent.

14. The chemically amplified positive resist composition according to claim 5 further comprises a photoacid generator.

15. The chemically amplified positive resist composition according to claim 5 further comprises at least one repeating unit selected from the following formula (E1), the following formula (E2), the following formula (E3), and the following formula (E4), and may also further comprise a polymer containing fluorine atoms selected from the following formula (E5) and the following formula (E6); In the formula, j1 is 1, 2 or 3; j2 is an integer that satisfies 0≤j2≤5+2(j3)-j1; j3 is 0 or 1; k is 1, 2 or 3; R B Each can be independently composed of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R C Each can be independently a hydrogen atom or a methyl group; R 201 R 202 R 204 and R 205 Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms; R 203 R 206 R 207 and R 208 Each of the following is independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-unstable group, and R 203 R 206 R 207 and R 208 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group can also be inserted between the carbon-carbon bonds; R 209 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, which may be hydrogen atoms or may also have heteroatom-containing groups inserted between carbon-carbon bonds; R 210 It can also be a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which heteroatoms are inserted between carbon-carbon bonds; R 211 It is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, and part of the -CH2- of the saturated hydrocarbon group may also be replaced by an ester bond or an ether bond; Z 1 It is a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms or a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms; Z 2 * represents a single bond, *-C(=O)-O-, or *-C(=O)-NH-; * represents an atomic bond with a carbon atom in the main chain; Z 3 For single bonds, -O-, *-C(=O)-OZ 31 -Z 32 -or *-C(=O)-NH-Z 31 -Z 32 -;Z 31 It is a single bond or a saturated alkylene group with 1 to 10 carbon atoms; Z 32 * represents a single bond, ester bond, ether bond, or sulfonamide bond; * represents an atomic bond with a carbon atom in the main chain.

16. The chemically amplified positive resist composition according to claim 5, further comprising a quencher other than the quencher according to claim 4.

17. A method for forming a resist pattern, comprising the following steps: A resist film is formed on a substrate using the chemically amplified positive resist composition according to any one of claims 5 to 16. The resist film was irradiated with high-energy rays to form a pattern, and The resist film that has been irradiated with the pattern is developed using an alkaline developer.

18. The method for forming a resist pattern according to claim 17, wherein, The high-energy rays are extreme ultraviolet rays or electron beams with wavelengths of 3–15 nm.

19. The method for forming a resist pattern according to claim 17, wherein, The outermost surface of the substrate is made of a chromium-containing material.

20. The method for forming a resist pattern according to claim 17, wherein, The substrate is a blank photomask.

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