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

Abstract

The objective of this invention is to provide a chemical amplification positive resist composition that exhibits good solvent solubility and excellent lithography properties such as resolution, LER, and pattern shape in photolithography using high-energy rays; and a method for pattern formation using the chemical amplification resist composition. The solution of this invention is a strontium salt represented by the following formula (A).

Description

Technical Field

[0001] This invention relates to strontium salts, chemically amplified positive inhibitor compositions, and methods for forming inhibitor patterns. Prior Technology

[0002] In recent years, with the increasing integration of integrated circuits, there is a demand for finer pattern formation. In the processing of patterns below 0.2μm, the focus is on using chemically amplified resist compositions that use acid as a catalyst. For the exposure source at this stage, high-energy rays such as ultraviolet light, far-ultraviolet light, and electron beams (EB) are used. EB lithography, in particular, is used as an ultra-fine processing technique and is indispensable in the processing of blank photomasks for semiconductor manufacturing. Regarding the resist compositions used in this type of photolithography, there are positive types that dissolve the exposed area to form a pattern, and negative types that leave the exposed area exposed to form a pattern. The choice depends on the desired resist pattern shape and is easy for the user to determine.

[0003] Generally, EB (Extended Electrode) irradiation does not use a mask. In positive cases, a method of sequentially irradiating the area outside the desired resist film residue area with a fine-area EB is employed. In negative cases, the area where the resist film residue is to be retained is irradiated sequentially. Because this involves scanning the entire finely divided area of ​​the processed surface, it is more time-consuming compared to a single exposure using a photomask. Therefore, to avoid reducing production volume, a high-sensitivity resist film is required. Furthermore, due to the long irradiation time, differences can easily arise between the initially irradiated areas and the later irradiated areas. The stability of the exposed areas over time in a vacuum is an important performance requirement. Furthermore, especially in the processing of blank photomasks for important applications, there are surface materials such as chromium compound films, primarily chromium oxide, that can easily affect the pattern shape of chemically amplified resist films when deposited on the photomask substrate. In order to maintain high resolution and etched shape, it is also considered important to keep the pattern outline of the resist film rectangular, regardless of the type of substrate.

[0004] The control of the sensitivity, pattern profile of the aforementioned resistor films has been variously improved according to the selection, combination, and process conditions of the materials used in the resistor compositions. With respect to one of the improvements, there is the problem of diffusion of acids that will have an important effect on the resolvability of the chemical amplifier resistor film. In photomask processing, it is required that the shape of the obtained resistor pattern does not vary depending on the time until post-exposure heating (PEB), however a large reason for the change in time dependence, is due to the diffusion of produced acid due to exposure. The problem of the diffusion of such acids, which is not limited to photomask processing, has been studied in general resistor compositions because it will have a large impact on sensibility and resolution.

[0005] Patent literatures 1 , 2 describe examples of decreasing roughness by inhibiting acid diffusion by increasing the volume of the acid produced from the acid-producing agent. However, the inhibition of acid diffusion is still inadequate in this type of acid-producing agent, so the development of acid-producing agents with smaller diffusion is desirable.

[0006] Also, patent literature 3~6 records examples of acid diffusion by resorting to bonding a sulfonic acid bond due to exposure to a resin used in a resistor composition. Such a method that will introduce a repeat unit of acid due to exposure into the base polymer to inhibit acid diffusion is effective in terms of obtaining patterns with small line edge roughness (LER). However, according to the structure, induction rate of such repeating unit, there will also be cases where problems arise in the solubility of the base polymer containing repeating units that will produce acid by exposure to organic solvents.

[0007] Also, a large number of polymers with aromatic skeletons with acidic side chains, such as polyhydroxystyrene, are used as materials for resistor compositions for KrF microshaping, but will not be used as materials for resistor compositions for ArF microshaping because they will exhibit large absorption for light near the wavelength of 200nm. However, it is important to consider the view that a high etching tolerance can be obtained in terms of resistor compositions for EB microshaping, compositions for resistors for extreme ultraviolet (EUV) microshaping, which are powerful techniques for forming patterns with smaller processing limits than those for ArF microshaping.

[0008] Regarding the base polymers of resist compositions for positive EB lithography and EUV lithography, the main approach is to use an acid generated from a photoacid generator by irradiation with high-energy rays as a catalyst to deprotect the acidic unstable groups (acid-decomposing protecting groups) that shield the acidic functional groups of the phenolic side chains of the base polymer, making the material soluble in alkaline developer. The aforementioned acid-unstable groups primarily include tertiary alkyl groups, tert-butoxycarbonyl groups, and acetal groups. Using protecting groups with lower activation energy for deprotection, such as acetal groups, can yield resist films with high sensitivity. However, if the diffusion of the generated acid is not sufficiently suppressed, deprotection reactions can occur in the unexposed areas of the resist film, leading to degradation of the LER (Light Emission Reduction) and a decrease in the dimensional uniformity of pattern linewidth (CDU).

[0009] With the recent advancements in the miniaturization of resist patterns, the control of acid diffusion generated by photoacid generators has become crucial, leading to the development of various acid diffusion control agents (quenchers). Regarding these quenchers, in addition to conventional amine compounds, onionium salt-type quenchers such as strontium salts and ferrous salts can be cited. Patent Document 7 describes onionium carboxylate salts with nitrogen-containing heterocyclic structures such as indole. Furthermore, Patent Documents 8-11 propose quenchers derived from betaine-type onionium salts in which phenylene oxide anions, carboxylate anions, or sulfadiazine anions are bonded within the same molecule as the strontium and ferrous cations. While the use of these quenchers has confirmed some degree of performance improvement, satisfactory results have not yet been achieved. To meet future miniaturization requirements, the development of resist materials with excellent photolithography properties and pattern shapes is also anticipated. [Previous Technical Documents] [Patent Literature]

[0010] [Patent Document 1] Japanese Patent Application Publication No. 2009-053518 [Patent Document 2] Japanese Patent Application Publication No. 2010-100604 [Patent Document 3] Japanese Patent No. 4425776 [Patent Document 4] Japanese Patent No. 5201363 [Patent Document 5] Japanese Patent No. 5231357 [Patent Document 6] International Publication No. 2008 / 081832 [Patent Document 7] Japanese Patent No. 6515831 [Patent Document 8] Japanese Patent No. 6848776 [Patent Document 9] Japanese Patent No. 6583136 [Patent Document 10] Japanese Patent No. 6246480 [Patent Document 11] Japanese Patent No. 7031537 Summary of the Invention

[0011] [The problem that the invention aims to solve] In recent years, in addition to straight line and spaced pattern (LS), isolated line pattern (IL), and isolated spaced pattern (IS), resist compositions with excellent hole pattern shape and excellent shape after pattern formation are also required.

[0012] The present invention is made in view of the foregoing circumstances, and aims to provide: a chemical amplifying positive resist composition with good solvent solubility and excellent lithography properties such as resolution, LER, and pattern shape, especially in photolithography using high-energy rays such as KrF excimer laser, ArF excimer laser, EB, and EUV; and a pattern forming method using the chemical amplifying resist composition. [Methods for solving problems]

[0013] The inventors of this invention, through repeated and dedicated research to achieve the aforementioned objectives, discovered that, in terms of quenching agents, using betaine-type strontium salts with alkyl chains having 6 to 18 carbon atoms or fluorinated alkyl chains having 4 to 18 carbon atoms, and containing strontium cations and sulfadiazine anions within the same molecule as components of chemically amplified positive type inhibitors, exhibits excellent solvent solubility, particularly in EB and EUV lithography, and demonstrates superior lithography properties such as resolution, LER, and pattern shape. This led to the completion of this invention.

[0014] That is, the present invention provides the following strontium salt, chemically amplified positive inhibitor composition and inhibitor pattern formation method. 1. A strontium salt, represented by the following formula (A). [Chemistry 1] 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; LA can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond, or carbamate bond; Ralk is an alkyl group having 6 to 18 carbon atoms or a fluorinated alkyl group having 4 to 18 carbon atoms; when Ralk 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; when Ralk 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; furthermore, in the aforementioned alkyl and fluorinated alkyl groups, one part of the -CH2- group may be replaced by an ether bond or a carbonyl group, and its terminal or carbon-carbon bond may contain a ring structure selected from cyclopentane ring, cyclohexane ring, adamantane ring, norcamphenic ring and benzene ring; Ra can be a halogen atom or a hydrocarbon group with 1 to 30 carbon atoms containing heteroatoms; furthermore, Ra and two of the two aromatic rings bonded to S+ in the formula can also bond to each other and form a ring together with the sulfur atoms bonded to them; Rb can also be a hydrocarbon group containing heteroatoms with 1 to 18 carbon atoms; R1 can be a halogen atom, nitro, cyano, hydroxyl, or may contain a hydrocarbon group with 1 to 20 carbon atoms, a hydrocarbon oxygen group with 1 to 20 carbon atoms, or a hydrocarbon thio group with 1 to 20 carbon atoms; when n2 is 2, 3, or 4, each R1 can be the same or different, and multiple R1s can also bond to each other and form a ring together with the carbon atoms they are bonded to; R2 can be a halogen atom, nitro, cyano, hydroxyl, 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 R2 can be the same or different from the others, and multiple R2s can also bond to each other and form a ring together with the carbon atoms they are bonded to. 2. The strontium salt of 1 is represented by the following formula (A1). [Chemistry 2] In the formula, n1~n4, LA, Ralk, Ra, Rb, R1 and R2 are the same as those mentioned above; n5 is 0 or 1; n6 is 0, 1, 2, 3 or 4; R3 can be a halogen atom, nitro, cyano, hydroxyl, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or 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; when n6 is 2, 3 or 4, each R3 can be the same or different from the others, and multiple R3s can also bond to each other and form a ring together with the carbon atoms they are bonded to. 3. The strontium salt of type 2 is represented by the following formula (A2). [Chemistry 3] In the formula, n2, n4, n6, LA, Ralk, Ra, Rb, R1, R2 and R3 are the same as those mentioned above. 4. A quenching agent comprising any one of the strontium salts described in 1 to 3. 5. A chemical amplification positive inhibitor composition comprising a quencher as described in 4. 6. The chemically amplified positive inhibitor composition of 5 further includes: a base polymer containing a polymer that decomposes due to the action of acid, thereby increasing its solubility in alkaline developing solutions. 7. A chemically amplified positive inhibitor composition as described in 6, wherein the polymer comprises a repeating unit represented by the following formula (B1). [Chemistry 4] In the formula, a1 is 0 or 1; a2 is 0, 1 or 2; a3 is an integer satisfying 0 ≤ a3 ≤ 5 + 2(a2) - a4; a4 is 1, 2 or 3; RA can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R11 can be a halogen atom, a nitro group, a carboxyl group, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom; A1 is a single bond or a saturated alkyl group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated alkyl group can also be substituted by -O-. 8. A chemically amplified positive inhibitor composition as in 6 or 7, wherein the polymer comprises a repeating unit represented by the following formula (B2-1). [Chemistry 5] In the formula, RA represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; 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; R21 is a halogen atom, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, or a 1-6 carbon saturated hydrocarbon oxygen group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom; A2 is a single bond or a saturated alkyl group with 1 to 10 carbon atoms; part of the -CH2- group of this saturated alkyl group can also be replaced by -O-. When X is 1, it is an acid-labile group; when it is 2 or 3, it is a hydrogen atom or an acid-labile group, but at least one of them is an acid-labile group. 9. A chemically amplified positive inhibitor composition as described in any one of 6 to 8, wherein the polymer comprises a repeating unit represented by the following formula (B2-2). [Chemistry 6] 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; RA can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R22 and R23 are each independently hydrocarbon groups with 1 to 10 carbon atoms, and may also contain heteroatoms. R22 and R23 can also bond with each other to form a ring together with the carbon atoms they are bonded to. R24 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; R25 can be an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms; A3 represents a single bond, an enantiomer, an enantiomer, or *-C(=O)-O-A31-; A31 may also contain a hydroxyl group, an ether bond, an ester bond, or an lactone ring, and has 1 to 20 carbon atoms, and may be an aliphatic enantiomer, or an enantiomer or an enantiomer. * indicates an atomic bond with a carbon atom in the main chain. 10. A chemical amplification positive inhibitor composition as described in any one of 6 to 9, wherein the polymer comprises 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). [Chemistry 7] 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; RA can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R31 and R32 are each independently a hydroxyl group, a halogen atom, a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, a 1-6 carbon saturated hydrocarbon oxygen group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom; R33 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; A4 is a single bond or a saturated alkyl group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated alkyl group can also be replaced by -O-. 11. A chemical amplification positive inhibitor composition as described in any one of 6 to 10, wherein the polymer comprises at least one repeating unit selected from the repeating unit represented by formula (B6), the repeating unit represented by formula (B7), the repeating unit represented by formula (B8), the repeating unit represented by formula (B9), and the repeating unit represented by formula (B10). [Chemistry 8] In the formula, g1 and g2 are each 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; Each of RA can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; Z1 is a single bond or may also have substituents; Z2 can be a single bond, **-C(=O)-O-Z21-, **-C(=O)-NH-Z21-, or **-O-Z21-; Z21 can be an aliphatic alkyl group with 1 to 6 carbon atoms, an alkylphenyl group, or a divalent group obtained by combining them, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups; Z3 can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Z4 is a single bond, or an aliphatic alkyl group with 1 to 6 carbon atoms, an alkylphenyl group, or a divalent group obtained by combining them. It may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups. Z5 is a single bond, or may contain substituents such as phenyl, naphthyl, or *-C(=O)-O-Z51-; Z51 is an aliphatic alkyl group, phenyl, or naphthyl group with 1 to 10 carbon atoms, which may also contain halogen atoms, hydroxyl groups, ether bonds, ester bonds, or lactone rings; Z6 can be a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Z7 can be a single bond, ***-Z71-C(=O)-O-, ***-C(=O)-NH-Z71-, or ***-O-Z71-; Z71 can also be an alkyl group with 1 to 20 carbon atoms containing heteroatoms; Z8 can be a single bond, ****-Z81-C(=O)-O-, ****-C(=O)-NH-Z81-, or ****-O-Z81-; Z81 can also be a alkyl group with 1 to 20 carbon atoms and may contain heteroatoms. Z9 can be a single bond, methylene, ethyl, phenyl, fluorinated phenyl, trifluoromethyl-substituted phenyl, *-C(=O)-O-Z91-, *-C(=O)-N(H)-Z91-, or *-O-Z91-; Z91 can be an aliphatic phenyl group with 1 to 6 carbon atoms, phenyl, fluorinated phenyl, or trifluoromethyl-substituted phenyl, 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 Z1; *** indicates an atomic bond with Z6; **** indicates an atomic bond with Z7; L1 can be a single bond, ether bond, ester bond, carbonyl group, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Rf1 and Rf2 are each independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; Rf3 and Rf4 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; Rf5 and Rf6 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; however, Rf5 and Rf6 cannot all be hydrogen atoms simultaneously. Rf7 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; R41 and R42 are each independently hydrocarbon groups with 1 to 20 carbon atoms, and may also contain heteroatoms; furthermore, R41 and R42 can also bond with each other to form a ring together with the sulfur atoms they are bonded to. R43 is a halogen atom other than fluorine, or it may be a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; when h3 is 2, 3 or 4, each R43 may be the same or different, and multiple R43s may also bond to each other and form a ring together with the carbon atoms they are bonded to; M- is a non-nucleophilic relative ion; A+ is an onium cation. 12. A chemical amplification positive inhibitor composition as described in any one of 6 to 11, wherein the content of repeating units having an aromatic ring skeleton in all repeating units of the base polymer is 60 mol% or more. 13. Any chemical amplification positive inhibitor composition as described in any of 5 to 12 further contains an organic solvent. 14. Any chemical amplification positive inhibitor composition as described in any of 5 to 13 further includes a photoacid generator. 15. The chemical amplification positive inhibitor composition of any one of 5 to 14 further comprises: a polymer containing at least one repeating unit selected from the repeating unit represented by formula (E1), the repeating unit represented by formula (E2), the repeating unit represented by formula (E3) and the repeating unit represented by formula (E4), and may also contain at least one repeating unit selected from the repeating unit represented by formula (E5) and the repeating unit represented by formula (E6). [Chemistry 9] 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; Each of RB is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; Each RC atom can be independently represented by a hydrogen atom or a methyl group; R201, R202, R204, and R205 are each independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms; R203, R206, R207, and R208 are each independently a hydrogen atom, a hydrocarbon group with 1 to 15 carbon atoms, a fluorinated hydrocarbon group with 1 to 15 carbon atoms, or an acid-unstable group. When R203, R206, R207, and R208 are hydrocarbon groups or fluorinated hydrocarbon groups, ether bonds or carbonyl groups may also be present between the carbon-carbon bonds. R209 is a hydrogen atom, or may be a straight-chain or branched hydrocarbon group containing heteroatoms with 1 to 5 carbon atoms separated by carbon-carbon bonds; R210 can also be a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, which may contain heteroatoms as intermediates between carbon-carbon bonds; R211 is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom. The -CH2- part of the saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. Z1 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; Z2 represents a single bond, *-C(=O)-O-, or *-C(=O)-NH-; * represents an atomic bond with a carbon atom in the main chain; Z3 is a single bond, -O-, *-C(=O)-O-Z31-Z32- or *-C(=O)-NH-Z31-Z32-; Z31 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms; Z32 is a single bond, ester bond, ether bond or sulfonamide bond; * is an atomic bond with a carbon atom in the main chain. 16. A chemical amplification positive inhibitor composition as described in any of 5 to 15, further comprising a quencher other than the quencher described in 4. 17. A method for forming a resist pattern, comprising the following steps: A resist film is formed on the substrate using a chemically amplified positive resist composition as described in any of 5 to 16; The resist film was irradiated with high-energy rays to create a pattern; and The resist film with the irradiated pattern was developed using an alkaline developer. 18. The resist pattern forming method of 17, wherein the high-energy ray is EUV or EB with a wavelength of 3~15nm. 19. The resist pattern forming method of 17, wherein the outermost surface of the substrate is made of a material containing chromium. 20. The resist pattern forming method of 17, wherein the substrate is a blank photomask. [Effects of the Invention]

[0015] 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. Implementation

[0016] The present invention will now be described in detail. Furthermore, in the following description, based on the structure represented by the chemical formula, there may be asymmetric carbons, and there may be mirror-image isomers and non-mirror-image isomers. In such cases, one of the chemical formulas will be used as a representative to represent these isomers. These isomers may be used individually or as a mixture of two or more.

[0017] [Salt] The strontium salt of this invention is represented by the following formula (A). [Chemistry 10]

[0018] 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, a benzene ring with n1 of 0 is more ideal. n2 is 0, 1, 2, 3, or 4. Considering raw material supply, n2 of 0, 1, or 2 is more ideal. 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, a benzene ring with n3 of 0 is more ideal. n4 is 0, 1, 2, 3, or 4. Considering raw material supply, n4 of 0, 1, or 2 is more ideal.

[0019] In formula (A), LA can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond, or carbamate bond. Among these, single bonds, ether bonds, ester bonds, and sulfonate bonds are more ideal, while ether bonds and ester bonds are more ideal.

[0020] In formula (A), Ralk is an alkyl group with 6 to 18 carbon atoms or a fluorinated alkyl group with 4 to 18 carbon atoms.

[0021] When Ralk is an alkyl group having 6 to 18 carbon atoms, the alkyl group has a straight-chain structure with at least one carbon atom having 6 or more carbon atoms. Specific examples of alkyl groups having 6 to 18 carbon atoms represented by Ralk include 1-hexyl, 1-heptyl, 1-octyl, 1-nonyl, 1-decyl, 1-undecyl, 1-dodecyl, 1-tridecyl, 1-tetradecyl, 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, the -CH2- group of the aforementioned alkyl groups can also be replaced by an ether bond or a carbonyl group, and the terminal or carbon-carbon bonds can also have a ring structure, such as a cyclopentane ring, a cyclohexane ring, an adamantane ring, a norcamphene ring, or a benzene ring. For Ralk, straight-chain alkyl groups or straight-chain ethylene glycol dimethyl ether chains are more ideal.

[0022] When Ralk 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. Specific examples of fluorinated alkyl groups having 4 to 18 carbon atoms represented by Ralk include groups such as 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, and 4-butyldodecyl, where some or all of the hydrogen atoms are replaced by fluorine atoms. Furthermore, the aforementioned fluorinated alkyl groups may also have their -CH2- groups substituted with ether bonds or carbonyl groups, and their ends or carbon-carbon bonds may also have cyclic structures, such as cyclopentane rings, cyclohexane rings, adamantane rings, norcamphenic rings, or benzene rings.

[0023] For Ralk, the following are ideal, but not limited to. Additionally, in the following formula, dashed lines represent atomic bonds. [Chemistry 11]

[0024] In formula (A), Ra is a halogen atom, or may contain a hydrocarbon group with 1 to 30 carbon atoms of heteroatoms.

[0025] Specific examples of halogen atoms represented by Ra include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc.

[0026] The hydrocarbon group represented by Ra can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1-30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, and tributyl; cyclic saturated hydrocarbon groups with 3-30 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2-30 carbon atoms such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3-30 carbon atoms such as cyclohexenyl; aryl groups with 6-30 carbon atoms such as phenyl, naphthyl, and thiophene; and aralkyl groups with 7-30 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl. Combinations of these groups to obtain aryl groups are preferred. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Similarly, the -CH2- part of the aforementioned hydrocarbon group can be replaced by a group 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.

[0027] Furthermore, Ra and two of the two aromatic rings bonded to S+ in the formula can also bond to each other and form a ring together with the sulfur atoms bonded to them. In this case, regarding the structure of the aforementioned ring, examples such as those shown in the following formulas can be listed. [Chemistry 12] In the formula, the dashed lines represent atomic bonds with the remaining substituent.

[0028] In formula (A), Rb is a hydrocarbon group with 1 to 18 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 include alkyl groups with 1 to 18 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, tributyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecanyl, and octadecyl; and cyclic saturated hydrocarbon groups with 3 to 18 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl. Alkenyl, allyl, propenyl, butenyl, hexenyl, and other alkenyl groups with 2 to 18 carbons; cyclohexenyl and other cyclounsaturated hydrocarbon groups with 3 to 18 carbons; aryl groups with 6 to 18 carbons, such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, dibutylphenyl, tributylphenyl, naphthyl, and other aryl groups; aralkyl groups with 7 to 18 carbons, such as benzyl, 1-phenylethyl, 2-phenylethyl, 1-naphthylethyl, 2-naphthylethyl; and groups obtained by combining these. Among these, aryl is the most ideal. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, the -CH2- group in the aforementioned hydrocarbon group can also be replaced by a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonate ring, carboxylic anhydride (-C(=O)-OC(=O)-), or haloalkyl groups. For Rb, methyl, ethyl, phenyl, tolyl, and trifluoromethyl groups are more ideal.

[0029] In formula (A), R1 can be a halogen atom, a nitro group, a cyano group, a 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. Regarding the aforementioned halogen atom, fluorine, chlorine, bromine, or iodine atoms are preferred, with fluorine or iodine atoms being even more ideal. 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, dibutyl, tributyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecanyl, octadecyl, nonadecanyl, and eicosyl; 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; cyclounsaturated cycloalkyl 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 them. Among these, aryl is the most ideal. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, the -CH2- group in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonate ring, carboxylic anhydride (-C(=O)-OC(=O)-), or haloalkyl groups. Also, when n2 is 2, 3, or 4, each R1 can be the same or different.

[0030] Furthermore, when n2 is 2, 3, or 4, the complex R1s can also bond with each other and form rings together with the carbon atoms they bond to. Specific examples of rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, and adamantane rings. Also, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms. Similarly, some of the -CH2- groups in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. As a result, the rings 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)-), and haloalkyl groups.

[0031] In formula (A), R2 can be a halogen atom, a nitro group, a cyano group, a 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. Regarding the aforementioned halogen atom, fluorine, chlorine, bromine, or iodine atoms are preferred, with fluorine or iodine atoms being more ideal. Furthermore, the aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed that are the same as those exemplified for the hydrocarbon group represented by R1, but are not limited to these. Also, when n4 is 2, 3, or 4, each R2 can be the same or different.

[0032] Furthermore, when n4 is 2, 3, or 4, the complex R2s can also bond to each other and form rings together with the carbon atoms they bond to. Specific examples of the rings formed in this case can be illustrated as those shown in the examples of rings formed by the complex R1s bonding to each other and the carbon atoms they bond to, but are not limited to these.

[0033] For strontium salts represented by formula (A), the following formula (A1) is more ideal. [Chemistry 13] In the formula, n1~n4, LA, Ralk, Ra, R1 and R2 are the same as those mentioned above.

[0034] 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, a benzene ring with n5 of 0 is more ideal. n6 is 0, 1, 2, 3, or 4. Considering raw material supply, n6 of 0, 1, or 2 is more ideal.

[0035] In formula (A1), R3 can be a halogen atom, a nitro group, a cyano group, a 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. Regarding the aforementioned halogen atom, fluorine, chlorine, bromine, or iodine atoms are preferred, with fluorine or iodine atoms being even more ideal. Furthermore, the aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed as those identical to those exemplified in the description of formula (A) for the hydrocarbon group represented by R1, but are not limited to these. Also, when n6 is 2, 3, or 4, each R3 can be the same or different.

[0036] Furthermore, when n6 is 2, 3, or 4, the complex R3s can also bond to each other and form rings together with the carbon atoms they bond to. Specific examples of the rings formed in this case can be listed as those exemplified in the explanation of formula (A) regarding the specific examples of rings that can be formed by the complex R1s bonding to each other and the carbon atoms they bond to, but are not limited to these.

[0037] For strontium salts represented by formula (A1), the following formula (A2) is more ideal. [Chemistry 14] In the formula, n2, n4, n6, LA, Ralk, Ra, Rb, R1, R2 and R3 are the same as those mentioned above.

[0038] Examples of preferred strontium salts represented by formula (A) are listed below, but are not limited to these. [Chemistry 15]

[0039] [Chemistry 16]

[0040] [Chemistry 17]

[0041] [Chemistry 18]

[0042] [Chemistry 19]

[0043] [Chemistry 20]

[0044] [Chemistry 21]

[0045] [Chemistry 22]

[0046] [Chemistry 23]

[0047] [Chemistry 24]

[0048] [Chemistry 25]

[0049] [Chemistry 26]

[0050] [Chemistry 27]

[0051] [Chemistry 28]

[0052] [Chemistry 29]

[0053] [Chemistry 30]

[0054] [Chemistry 31]

[0055] [Chemistry 32]

[0056] [Chemistry 33]

[0057] The strontium salt of this invention can be synthesized by known methods. Specifically, the synthesis methods described in paragraphs

[0026] to

[0027] of Japanese Patent No. 7031637 can be used, but are not limited to these.

[0058] The strontium salt represented by formula (A) is characterized by having a sulfadiazine anion structure exhibiting basicity on the aromatic ring forming the strontium cation, and a chain of alkyl groups with 6 to 18 carbon atoms or a chain of fluorinated alkyl groups with 4 to 18 carbon atoms. It is believed that the aforementioned alkyl and fluorinated alkyl groups increase solvent solubility and have high lipid solubility, therefore the strontium salt represented by formula (A) will be distributed in the upper layer of the resist film. In particular, in EB lithography, when drawing an electron beam, the effect of forward scattering caused by the electron beam cannot be avoided in the exposed area. When using conventional quenchers, the deprotection reaction in the upper part of the pattern may be excessive, raising concerns that the upper part of the pattern may become a rounded shape with rounded corners. However, by using the quencher of this invention, the 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 sulfadiazine anion within the same molecule is highly basic, effectively quenching the acid diffusion that produces acid. It is believed that, through these synergistic effects, when using the strontium salt of the present invention, patterns with good resolution, high contrast, good CDU, and low LER can be obtained, and patterns with good rectangularity can be obtained.

[0059] The strontium salt of this invention is ideally suited for use as a quenching agent.

[0060] [Chemical Amplification Positive Inhibitor Composition] [(A) Quenching agent] The chemically amplified positive resist composition of the present invention, in terms of component (A), includes a quencher composed of a strontium salt represented by formula (A) as an essential component. Furthermore, in the present invention, the term "quencher" refers to a compound that captures the acid generated from the acid-generating agent. This suppresses the diffusion rate of the acid generated from the acid-generating agent within the resist film, and when using a substrate made of a material whose outermost surface contains chromium as the substrate, it also suppresses the influence of the acid generated within the resist film on the chromium-containing material.

[0061] In the chemical amplification positive inhibitor composition of this invention, the content of (A) quencher is ideally 0-50 parts by mass relative to 80 parts by mass of the base polymer (B) described later, and even more ideally 0.1-40 parts by mass. If the content of the quencher falls within the aforementioned range, the generated acid will be effectively captured, resulting in a good pattern shape. Furthermore, good storage stability is also achieved. (A) Quencher can be used alone or in combination of two or more.

[0062] [(B) Basic Polymer] Regarding component (B), the inhibitor composition of the present invention comprises a base polymer containing a polymer that decomposes due to the action of acid, thereby increasing its solubility in alkaline developing solutions.

[0063] For the aforementioned polymers, polymers containing repeating units represented by the following formula (B1) (hereinafter also referred to as repeating unit B1) are more desirable. [Chemistry 34]

[0064] In formula (B1), a1 is 0 or 1. a2 is 0, 1, or 2; when a2 is 0, it represents the benzene skeleton; when a2 is 1, it represents the naphthalene skeleton; and when a2 is 2, it 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, the more ideal system is a3 = 0, 1, 2, or 3 and a4 = 1, 2, or 3. When a2 is 1 or 2, the more ideal system is a3 = 0, 1, 2, 3, or 4 and a4 = 1, 2, or 3.

[0065] In formula (B1), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0066] In formula (B1), R11 can be a halogen atom, a nitro group, a carboxyl group, a saturated hydrocarbon group with 1 to 6 carbon atoms that can be substituted with a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that can be substituted with a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that can be substituted with a halogen atom. The aforementioned saturated hydrocarbon group, as well as the saturated hydrocarbon group and the saturated hydrocarbon carbonyl oxygen 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 a3 is 2 or more, each R11 can be the same or different.

[0067] In formula (B1), A1 is a single bond or a saturated alkyl group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated alkyl group can also be replaced by -O-. The aforementioned saturated alkyl group can be linear, branched, or cyclic. Specific examples include alkyl diyl groups with 1 to 10 carbon atoms such as 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; cyclic saturated alkyl groups with 3 to 10 carbon atoms such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining them. When the aforementioned saturated alkyl group contains an ether bond, when a1 in formula (B1) is 1, it can be inserted anywhere except between the carbon atoms at the α-position and 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 anywhere except between the carbon atoms at the α and β positions 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 solutions can be obtained, which is ideal.

[0068] When a1 is 0 and A1 is a single bond, that is, when the aromatic ring system is directly bonded to the polymer backbone (i.e., without a linker group (-C(=O)-O-A1-)), preferred examples of repeating unit B1 include units derived from 3-hydroxystyrene, 4-hydroxystyrene, 5-hydroxy-2-vinylnaphthalene, 6-hydroxy-2-vinylnaphthalene, etc. Specifically, examples are shown below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 35]

[0069] [Chemistry 36]

[0070] [Chemistry 37]

[0071] When a1 is 1 (i.e., has -C(=O)-O-A1- as a linking base), for a preferred example of repeating unit B1, examples can be listed as shown below, but are not limited to these. In addition, in the following formula, RA is the same as described above. [Chemistry 38]

[0072] [Chemistry 39]

[0073] [Chemistry 40]

[0074] [Chemistry 41]

[0075] [Chemistry 42]

[0076] The content of repeating unit B1 is ideally 15-90 mol% among all repeating units constituting the aforementioned polymer, and more ideally 15-80 mol%. However, when it contains at least one of the repeating units represented by formula (B3) and formula (B4) that provide higher etch resistance to the polymer, and the unit has a phenolic hydroxyl group as a substituent, it is also ideal to add this proportion to fall within the aforementioned range. Repeating unit B1 can be used alone or in combination of two or more.

[0077] The aforementioned polymer, as a positive resist component, imparts the characteristic that the exposure unit can dissolve in alkaline developing solution. Therefore, it is more ideal to include repeating units with acidic functional groups protected by acid-insecure groups, that is, repeating units that are protected by acid-insecure groups and become alkali-soluble due to the action of acid (hereinafter, also referred to as repeating unit B2).

[0078] The best repeating unit B2 can be represented by the following formula (B2-1) (hereinafter also referred to as repeating unit B2-1). [Chemistry 43]

[0079] 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, ideally b3 is 0, 1, 2, or 3 and b4 is 1, 2, or 3. When b2 is 1 or 2, ideally b3 is 0, 1, 2, 3, or 4 and b4 is 1, 2, or 3.

[0080] In formula (B2-1), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0081] In formula (B2-1), R21 is a halogen atom, a saturated hydrocarbon group with 1 to 6 carbon atoms that may be substituted with a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that may be substituted with a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that may be substituted with a halogen atom. The aforementioned saturated hydrocarbon group, as well as the saturated hydrocarbon oxygen group and the saturated hydrocarbon carbonyl oxygen 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 R21 can be the same or different.

[0082] In formula (B2-1), A2 is a single bond or a saturated alkyl group with 1 to 10 carbon atoms. Part of the -CH2- group of this saturated alkyl group can also be replaced by -O-. The aforementioned saturated alkyl group can be linear, branched, or cyclic. Specific examples include alkyl diyl groups with 1 to 10 carbon atoms such as 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; cyclic saturated alkyl groups with 3 to 10 carbon atoms such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining these. When the aforementioned saturated alkyl group contains an ether bond, b1 in formula (B2-1) can be inserted anywhere except between the carbon atoms at the α-position and 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 anywhere except 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.

[0083] 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 of them is an acid-labile group. That is, the repeating unit B2-1 is either a phenolic hydroxyl group bonded to the aromatic ring that is protected by an acid-labile group, or a carboxyl group bonded to the aromatic ring that is protected by an acid-labile group. Regarding the aforementioned acid-labile group, it is not particularly limited to those that are used in most known chemical amplification inhibitor compositions and can provide an acidic group due to acid removal.

[0084] Regarding the aforementioned acid-instable groups, examples include tertiary saturated hydrocarbon groups. For obtaining the monomers for polymerization by distillation, tertiary saturated hydrocarbon groups with 4 to 18 carbon atoms are more ideal.

[0085] For the saturated hydrocarbon groups bonded to the tertiary carbon atoms of the aforementioned tertiary saturated hydrocarbon groups, those with 1 to 15 carbon atoms are more ideal. These saturated hydrocarbon groups with 1 to 15 carbon atoms can be linear, branched, or cyclic, and their carbon-carbon bonds can also 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 to form rings together with their bonded tertiary carbon atoms.

[0086] Examples of alkyl substituents mentioned above include methyl, ethyl, propyl, adamantyl, norbornel, tetrahydrofuran-2-yl, 7-oxanorborne-2-yl, cyclopentyl, 2-tetrahydrofuranyl, tricyclo[5.2.1.02,6]decyl, 8-ethyl-8-tricyclo[5.2.1.02,6]decyl, 3-methyl-3-tetracyclo[4.4.0.12,5.17,10]dodecyl, tetracyclo[4.4.0.12,5.17,10]dodecyl, 3-sideoxy-1-cyclohexyl, etc.

[0087] Examples of the aforementioned tertiary saturated hydrocarbon groups include: 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-ethylcyclopentyl, 1-propylcyclopentyl, 1-cyclopentylcyclopentyl, 1-cyclohexylcyclopentyl, 1-(2-tetrahydrofuranyl)cyclopentyl, 1-(7-oxanorborneol-2-yl)cyclopentyl, 1-methylcyclohexyl, 1-ethylcyclohexyl, 1-cyclopentylcyclohexyl, 1-cyclohexylcyclohexyl, and 1-cyclohexyl ... Hexyl, 2-methyl-2-norborneol, 2-ethyl-2-norborneol, 8-methyl-8-tricyclo[5.2.1.02,6]decyl, 8-ethyl-8-tricyclo[5.2.1.02,6]decyl, 3-methyl-3-tetracyclo[4.4.0.12,5.17,10]dodecyl, 3-ethyl-3-tetracyclo[4.4.0.12,5.17,10]dodecyl, 2-methyl-2-adamantyl, 2-ethyl-2-adamantyl, 1-methyl-3-sideoxy-1-cyclohexyl, 1-methyl-1-(tetrahydrofuran-2-yl)ethyl, 5-hydroxy-2-methyl-2-adamantyl, 5-hydroxy-2-ethyl-2-adamantyl, but not limited to these.

[0088] Furthermore, regarding the aforementioned acid-indestructible groups, the group represented by formula (B2-1-1) can be listed below. The group represented by formula (B2-1-1) is frequently used as an acid-indestructible group, and is a useful option as an acid-indestructible group that provides a relatively stable pattern with a rectangular interface between the pattern and the substrate. When X is a group represented by formula (B2-1-1), an acetal structure is formed. [Chemistry 44] In the formula, the dashed lines represent atomic bonds.

[0089] In formula (B2-1-1), RL1 is a hydrogen atom or a saturated hydrocarbon group with 1 to 10 carbon atoms. The aforementioned saturated hydrocarbon group can be linear, branched, or cyclic.

[0090] The RL1 group is appropriately selected based on the sensitivity of the decomposable group to acids. For example, if the design aims to ensure high stability through decomposition with strong acids, a group with a hydrogen atom or a tertiary carbon atom bonded to the acetal carbon is ideal. Examples of RL1 groups with tertiary carbon atoms bonded to the acetal carbon include tributyl, tripentyl, and 1-adamantyl, but are not limited to these. If the design aims for high reactivity and high sensitivity to pH changes, a straight-chain alkyl group is ideal. While the combination of acid-generating agents and quenchers incorporated into the inhibitor composition also matters, for RL1, a larger alkyl group at the end is preferred for RL2, and for designs that result in significant changes in solubility due to decomposition, a secondary carbon atom bonded to the acetal carbon is ideal. Examples of RL1 groups with secondary carbon atoms bonded to the acetal carbon include isopropyl, tributyl, cyclopentyl, and cyclohexyl, but are not limited to these.

[0091] In formula (B2-1-1), RL2 is a hydrocarbon group with 1 to 30 carbon atoms. This hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Part of the -CH2- group is replaced by heteroatoms such as oxygen or sulfur atoms, resulting in the presence of ether bonds, thioether bonds, etc. 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. In particular, for achieving higher resolution in fine pattern formation, it is ideal for RL2 to be a hydrocarbon group with 1 to 6 carbon atoms. When RL2 is a hydrocarbon group with 1 to 6 carbon atoms, the alcohol formed after the acid-induced deprotection reaction is water-soluble and will dissolve in the developing solution during positive pattern formation in the alkaline developing solution, thus suppressing residual defects in the exposed area.

[0092] For preferred examples of the basis represented by equation (B2-1-1), examples can be listed as shown below, but are not limited to these. Furthermore, in the following equation, RL1 is the same as described above, and dashed lines represent atomic bonds. [Chemistry 45]

[0093] [Chemistry 46]

[0094] Regarding other acid-labile groups, those formed by replacing the hydrogen atom of the phenolic hydroxyl group with -CH2COO- (a tertiary saturated hydrocarbon group) can also be used. In this case, the aforementioned tertiary saturated hydrocarbon group can be the same as the tertiary saturated hydrocarbon group used in the protection of the aforementioned phenolic hydroxyl group.

[0095] Furthermore, regarding the repeating unit B2, the repeating unit represented by the following formula (B2-2) (hereinafter also referred to as repeating unit B2-2) can also be listed. Because the dissolution rate of the exposure section will increase, repeating unit B2-2 is a useful option as a unit containing acid-inhibited groups that provides good performance against linewidth variations in the developing load. [Chemistry 47]

[0096] 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.

[0097] In formula (B2-2), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0098] In formula (B2-2), R22 and R23 are each independently hydrocarbon groups with 1 to 10 carbon atoms, which may also contain heteroatoms. R22 and R23 may also bond to each other and form a ring together with the carbon atoms they bond to.

[0099] In formula (B2-2), R24 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.

[0100] In formula (B2-2), R25 is an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms.

[0101] In formula (B2-2), A3 is a single bond, an enylphenyl, an enylnaphthyl, or *-C(=O)-O-A31-. A31 is an aliphatic enyl group with 1 to 20 carbon atoms, which may also contain a hydroxyl group, an ether bond, an ester bond, or an lactone ring, or an enylphenyl or enylnaphthyl. * indicates an atomic bond with a carbon atom in the main chain.

[0102] For a preferred example of repeating unit B2-2, examples as shown below can be listed, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 48]

[0103] [Chemistry 49]

[0104] The content of repeating unit B2 is ideally 5-95 mol% among all repeating units constituting the aforementioned polymer, and even more ideally 20-80 mol%. Repeating unit B2 can be used alone or in combination of two or more types.

[0105] 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 units represented by formula (B4) (hereinafter also referred to as repeating unit B4.), and the repeating units represented by formula (B5) (hereinafter also referred to as repeating unit B5.). [Transformation 50]

[0106] In equations (B3) and (B4), d is 0, 1, 2, 3, 4, 5, or 6. e is 0, 1, 2, 3, or 4.

[0107] In formulas (B3) and (B4), R31 and R32 are each independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 6 carbon atoms that may be substituted with a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that may be substituted with a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that may be substituted with a halogen atom. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxygen group, and saturated hydrocarbon carbonyl oxygen group can be linear, branched, or cyclic. When d is 2 or more, each R31 can be the same or different. When e is 2 or more, each R32 can be the same or different.

[0108] 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 is ideally 0, 1, 2, or 3; when f2 is 1 or 2, f3 is ideally 0, 1, 2, 3, or 4.

[0109] In formula (B5), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0110] In formula (B5), R33 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 thioalkyl 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. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxygen group, saturated hydrocarbon carbonyl oxygen group, saturated hydrocarbon thioalkyl group, and saturated hydrocarbon thioalkyl group can be linear, branched, or cyclic. When f3 is 2 or more, each R33 can be the same or different.

[0111] In formula (B5), A4 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. For specific examples, those that are the same as those exemplified in the description of A1 in formula (B1) can be listed.

[0112] When at least one of repeating units B3 to B5 is used as a constituent unit of the aforementioned polymer, the etching resistance of the aromatic ring and the etching resistance and EB irradiation resistance during pattern inspection can be improved by adding a ring structure to the main chain.

[0113] To achieve improved etching resistance, the content of repeating units B3-B5 is ideally 5 mol% or more among all repeating units constituting the aforementioned polymer. Furthermore, the content of repeating units B3-B5 is ideally 25 mol% or less, and even more ideally 20 mol% or less among all repeating units constituting the aforementioned polymer. If the amount introduced is 25 mol% or less when there are no functional groups or when the functional groups are other than hydroxyl groups, there is no risk of development defects, and this is therefore ideal. Repeating units B3-B5 can be used alone or in combination of two or more.

[0114] Considering the need for a good balance between high etch resistance and resolution, it is ideal for the aforementioned polymer to include repeating unit B1, repeating unit B2, and at least one selected from repeating units B3 to B5. Ideally, these repeating units should contain at least 60 mol% of the total repeating units in the polymer, more ideally at least 70 mol%, even more ideally at least 80 mol%, and even more ideally at least 90 mol%.

[0115] The aforementioned polymer may also contain at least one of the repeating units represented by formula (B6) (hereinafter also referred to as repeating unit B6.), the repeating units represented by formula (B7) (hereinafter also referred to as repeating unit B7.), the repeating units represented by formula (B8) (hereinafter also referred to as repeating unit B8.), the repeating units represented by formula (B9) (hereinafter also referred to as repeating unit B9.), and the repeating units represented by formula (B10) (hereinafter also referred to as repeating unit B10.). [Chemistry 51]

[0116] In formulas (B6) to (B10), RA is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z1 is a single bond or may be a phenyl group with substituents. Z2 is a single bond, **-C(=O)-O-Z21-, **-C(=O)-NH-Z21-, or **-O-Z21-. Z21 is an aliphatic alkyl group with 1 to 6 carbon atoms, a phenyl 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. Z3 is a single bond, an ether bond, an ester bond, an amide bond, a sulfonate bond, a sulfonamide bond, a carbonate bond, or a carbamate bond. Z4 is a single bond, or an aliphatic alkyl group with 1 to 6 carbon atoms, a phenyl 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. Z5 is independently a single bond, and may also contain substituents such as phenyl, naphthyl, or *-C(=O)-O-Z51-. Z51 is an aliphatic alkyl group, phenyl, or naphthyl with 1 to 10 carbon atoms, which may also contain halogen atoms, hydroxyl groups, ether bonds, ester bonds, or lactone rings. Z6 is a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. Z7 is independently a single bond, ***-Z71-C(=O)-O-, ***-C(=O)-NH-Z71-, or ***-O-Z71-. Z71 may also contain heteroatoms and is an alkyl group with 1 to 20 carbon atoms. Z8 is independently a single bond, ****-Z81-C(=O)-O-, ****-C(=O)-NH-Z81-, or ****-O-Z81-. Z81 is an alkyl group with 1 to 20 carbon atoms, which may also contain heteroatoms. Z9 is a single bond, methylene, ethyl, phenyl, fluorinated phenyl, trifluoromethyl-substituted phenyl, *-C(=O)-O-Z91-, *-C(=O)-N(H)-Z91-, or *-O-Z91-. Z91 is an aliphatic alkyl group with 1 to 6 carbon atoms, phenyl, fluorinated phenyl, or trifluoromethyl-substituted phenyl, which may also contain carbonyl, ester, ether, or hydroxyl groups. * indicates an atomic bond with a carbon atom in the main chain. ** indicates an atomic bond with Z1. *** indicates an atomic bond with Z6. **** indicates an atomic bond with Z7.

[0117] Z21, Z51, and Z91 represent aliphatic alkyl groups, which can be straight-chain, branched, or cyclic. Specific examples include alkyl groups such as 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, and hexane-1,6-diyl; cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining them.

[0118] Z71 and Z81 can also contain heteroatomic extended hydrocarbon groups, which can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples are shown below, but are not limited to these. [Chemistry 52] In the formula, the dashed lines represent atomic bonds.

[0119] In formula (B6), R41 and R42 are each independently a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon groups may be saturated or unsaturated, and may 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, dibutyl, and tributyl; cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornel, and adamantyl; alkenyl groups with 2 to 20 carbon atoms, such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclohexenyl and other cyclounsaturated hydrocarbon groups with 3 to 20 carbon atoms; 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 more ideal aryl groups. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Similarly, the -CH2- part of the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may also 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, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0120] Furthermore, R41 and R42 can also bond to each other to form a ring together with the sulfur atoms they are bonded to. In this case, specific examples of the aforementioned rings can be listed as follows. [Chemistry 53] In the formula, the dashed lines represent atomic bonds with Z4.

[0121] Specific examples of the cation in repeating unit B6 can be listed as shown below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 54]

[0122] [Chemistry 55]

[0123] [Chemistry 56]

[0124] [Chemistry 57]

[0125] [Chem.58]

[0126] [Chemistry 59]

[0127] [Transformation 60]

[0128] [Chemistry 61]

[0129] [Chemistry 62]

[0130] [Chemistry 63]

[0131] In formula (B6), M- represents a non-nucleophilic relative ion. Among the aforementioned non-nucleophilic relative ions, halide ions, sulfonic acid anions, acetylinic acid anions, and methylated acid anions are ideal. Specific examples of halide ions include chloride ions and bromide ions. Specific examples of sulfonic acid anions (sulfonate ions) include fluoroalkyl sulfonate ions such as trifluoromethanesulfonate ions, 1,1,1-trifluoroethanesulfonate ions, and nonafluorobutanesulfonate ions; aryl sulfonate ions such as toluenesulfonate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, and 1,2,3,4,5-pentafluorobenzenesulfonate ions; and alkyl sulfonate ions such as methanesulfonate ions and butanesulfonate ions. Specific examples of the aforementioned aceimide anions (aceimide ions) include bis(trifluoromethylsulfonyl)aceimide ions, bis(perfluoroethylsulfonyl)aceimide ions, and bis(perfluorobutylsulfonyl)aceimide ions. Specific examples of the aforementioned methylated acid anions (methylated ions) include trifluoromethylsulfonyl methylated ions and trifluoroethylsulfonyl methylated ions.

[0132] For other examples of the aforementioned non-nucleophilic relative ions, anions represented by any of the following formulas (B6-1) to (B6-4) can be listed. [Chemistry 64]

[0133] In formula (B6-1), Rfa is a fluorine atom, or may contain a hydrocarbon group with 1 to 40 carbon atoms and heteroatoms. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. For specific examples, those identical to those exemplified by the hydrocarbon group represented by Rfa1 in formula (B6-1-1) described later can be listed.

[0134] For anions represented by formula (B6-1), the one represented by formula (B6-1-1) is more ideal. [Chemistry 65]

[0135] In formula (B6-1-1), Q1 and Q2 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group with 1 to 6 carbon atoms. However, for improved solvent solubility, at least one of them being trifluoromethyl is preferred. m can be 0, 1, 2, 3, or 4, with 1 being particularly ideal. Rfa1 can also be a hydrocarbon group with 1 to 35 carbon atoms containing heteroatoms. Regarding the aforementioned heteroatoms, oxygen, nitrogen, sulfur, and halogen atoms are preferred, with oxygen atoms being even more ideal. Regarding the aforementioned hydrocarbon groups, considering the need to obtain high resolution in the formation of fine patterns, those with 6 to 30 carbon atoms are particularly ideal.

[0136] In formula (B6-1-1), Rfa1 represents a hydrocarbon group with 1 to 35 carbon atoms that 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, dibutyl, tributyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecanyl, and eicosyl; 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-enyl; aralkyl groups with 7 to 35 carbon atoms, such as benzyl and diphenylmethyl; and groups obtained by combining them.

[0137] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, the -CH2- part of the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain 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, acetaminomethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetoxymethyl, 2-carboxy-1-cyclohexyl, 2-sideoxypropyl, 4-sideoxy-1-adamantyl, 3-sideoxycyclohexyl, etc.

[0138] In formula (B6-1-1), La1 can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond. From a synthetic point of view, ether bond or ester bond is more ideal, and ester bond is even more ideal.

[0139] Specific examples of anions represented by formula (B6-1) are shown below, but are not limited to these. Furthermore, in the following formula, Q1 is the same as described above, and Ac is acetyl. [Chemistry 66]

[0140] [Chemistry 67]

[0141] [Chemistry 68]

[0142] [Chemistry 69]

[0143] [Chemistry 70]

[0144] [Chemistry 71]

[0145] [Chemistry 72]

[0146] [Chemistry 73]

[0147] [Chemistry 74]

[0148] [Chemistry 75]

[0149] In formula (B6-2), Rfb1 and Rfb2 are each independently a fluorine atom, or may contain heteroatoms and be a hydrocarbon group with 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 as those exemplified by the hydrocarbon group represented by Rfa1 in formula (B6-1-1). Ideally, Rfb1 and Rfb2 should be fluorine atoms or linear fluorinated alkyl groups with 1 to 4 carbon atoms. Furthermore, Rfb1 and Rfb2 can also bond to each other and form a ring with the group they are bonded to (-CF2-SO2-N--SO2-CF2-). In this case, the group obtained by the mutual bonding of Rfb1 and Rfb2 is preferably fluorinated ethyl or fluorinated propyl.

[0150] In formula (B6-3), Rfc1, Rfc2, and Rfc3 are each independently a fluorine atom, or may contain heteroatoms and be a hydrocarbon group with 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 as those exemplified by the hydrocarbon group represented by Rfa1 in formula (B6-1-1). Ideally, Rfc1, Rfc2, and Rfc3 should be fluorine atoms or linear fluorinated alkyl groups with 1 to 4 carbon atoms. Furthermore, Rfc1 and Rfc2 can also bond to each other and form a ring with the group they are bonded to (-CF2-SO2-C--SO2-CF2-). In this case, the group obtained by the mutual bonding of Rfc1 and Rfc2 is preferably a fluorinated ethyl or fluorinated propyl group.

[0151] In formula (B6-4), Rfd is a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. For specific examples, those that are the same as those exemplified by the hydrocarbon group represented by Rfa1 in formula (B6-1-1) can be listed.

[0152] Specific examples of anions represented by formula (B6-4) can be listed as shown below, but are not limited to these. [Chemistry 76]

[0153] [Chemistry 77]

[0154] In addition to the aforementioned examples of non-nucleophilic relative ions, examples of anions with aromatic rings substituted by iodine or bromine atoms can also be cited. Specific examples of such anions can be represented by the following formula (B6-5). [Chemistry 78]

[0155] 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. Only 1 ≤ y + z ≤ 5. y being 1, 2, or 3 is more ideal, with 2 or 3 being even more ideal. z being 0, 1, or 2 is more ideal.

[0156] In formula (B6-5), XBI is an iodine atom or a bromine atom, and when x and / or y are 2 or more, they can be the same or different.

[0157] In formula (B6-5), L11 is a single bond, ether bond, or ester bond, or may contain a saturated alkyl group with 1 to 6 carbon atoms that is an ether bond or ester bond. The aforementioned saturated alkyl group may be linear, branched, or cyclic.

[0158] In formula (B6-5), L12 is a single bond or a divalent linker with 1 to 20 carbon atoms when x is 1, and a (x+1) valent linker with 1 to 20 carbon atoms when x is 2 or 3. The linker may also contain oxygen, sulfur or nitrogen atoms.

[0159] In formula (B6-5), Rfe is a hydroxyl, carboxyl, fluorine, chlorine, bromine, or amino group, or may contain a 1-20 carbon-1 hydrocarbon group, a 1-20 carbon-1 hydrocarbon oxygen group, a 2-20 carbon-2 hydrocarbon carbonyl group, a 2-20 carbon-2 hydrocarbon oxycarbonyl group, a 2-20 carbon-2 hydrocarbon carbonyl oxygen group, or a 1-20 carbon-1 hydrocarbon sulfonyl oxygen group, or -N(RfeA)(RfeB), -N(RfeC)-C(=O)-RfeD, or -N(RfeC)-C(=O)-O-RfeD. RfeA and RfeB are each independently a hydrogen atom or a 1-6 carbon-1 saturated hydrocarbon group. RfeC is a hydrogen atom or a saturated hydrocarbon group with 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group with 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl group with 2 to 6 carbon atoms. RfeD 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 oxygen group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group with 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl group with 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon groups may be saturated or unsaturated, and may be linear, branched, or cyclic. The aforementioned hydrocarbon groups, hydrocarbon oxygen groups, hydrocarbon carbonyl groups, hydrocarbon oxycarbonyl groups, hydrocarbon carbonyl groups, and hydrocarbon sulfonyl groups may be linear, branched, or cyclic. When x and / or z are 2 or more, each Rfe may be the same or different.

[0160] Among these, for Rfe, hydroxyl, -N(RfeC)-C(=O)-RfeD, -N(RfeC)-C(=O)-O-RfeD, fluorine atom, chlorine atom, bromine atom, methyl, methoxy, etc. are more ideal.

[0161] In formula (B6-5), Rf11 to Rf14 are each independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group. Furthermore, Rf11 and Rf12 can also combine to form a carbonyl group. Ideally, both Rf13 and Rf14 should be fluorine atoms.

[0162] Specific examples of anions represented by formula (B6-5) can be listed as shown below, but are not limited to these. Furthermore, in the following formula, XBI is the same as described above. [Chemistry 79]

[0163] [Chemistry 80]

[0164] [Chemistry 81]

[0165] [Chemistry 82]

[0166] [Chemistry 83]

[0167] [Chemistry 84]

[0168] [Chemistry 85]

[0169] [Chemistry 86]

[0170] [Chemistry 87]

[0171] [Chemistry 88]

[0172] [Chemistry 89]

[0173] [Chemistry 90]

[0174] [Chemistry 91]

[0175] [Chemistry 92]

[0176] [Chemistry 93]

[0177] [Chemistry 94]

[0178] [Chem. 95]

[0179] [Chemistry 96]

[0180] [Chemistry 97]

[0181] [Chem. 98]

[0182] [Chemistry 99]

[0183] [Chemistry 100]

[0184] [Chemistry 101]

[0185] Regarding the aforementioned non-nucleophilic relative ions, the following can also be used: the fluorobenzenesulfonic acid anion bonded to an aromatic group containing an iodine atom as described in Japanese Patent No. 6648726; the anion with a mechanism of decomposition by 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.

[0186] Regarding the aforementioned non-nucleophilic relative ions, the following can also be used: the anions of benzenesulfonic acid derivatives without fluorine atoms that are highly bulky and do not have fluorine atoms as described in Japanese Patent Application Publication No. 2006-276759, Japanese Patent Application Publication No. 2015-117200, Japanese Patent Application Publication No. 2016-65016 and Japanese Patent Application Publication No. 2019-202974; the benzenesulfonic acid anions and alkylsulfonic acid anions that are bonded to an aromatic group containing an iodine atom and do not contain fluorine atoms as described in Japanese Patent No. 6645464.

[0187] Regarding the aforementioned non-nucleophilic relative ions, the anions of disulfonic acid described in Japanese Patent Application Publication No. 2015-206932, the anions of sulfonamide and sulfenimide with one side being sulfonic acid and the other side being different, as described in International Patent Application Publication No. 2020 / 158366, and the anions of carboxylic acid with one side being sulfonic acid and the other side being different, as described in Japanese Patent Application Publication No. 2015-24989, can also be used.

[0188] In equations (B7) and (B8), g1 and g2 are each independently 0, 1, 2 or 3, with 1 being the most ideal.

[0189] 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.

[0190] In formulas (B7), (B8), and (B9), L1 can be a single bond, ether bond, ester bond, carbonyl group, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. From a synthetic point of view, ether bonds, ester bonds, and carbonyl groups are more ideal, with ester bonds and carbonyl groups being even more ideal.

[0191] In formula (B7), Rf1 and Rf2 are each independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among these, for Rf1 and Rf2, it is more desirable for both to be fluorine atoms to improve the acid strength of the produced acid. Rf3 and Rf4 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among these, it is more desirable for at least one of Rf3 and Rf4 to be trifluoromethyl to improve solvent solubility.

[0192] In formula (B8), Rf5 and Rf6 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. However, not all Rf5 and Rf6 are simultaneously hydrogen atoms. Among these, it is ideal for at least one of Rf5 and Rf6 to be trifluoromethyl for improved solvent solubility.

[0193] In formula (B9), Rf7 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. For Rf7, a fluorine atom, trifluoromethyl, difluoromethyl, trifluoromethoxy, difluoromethoxy, trifluoromethylthio, or difluoromethylthio is more ideal, while a fluorine atom, trifluoromethyl, or trifluoromethoxy is even more ideal. When h2 is 2, 3, or 4, each Rf7 can be the same or different.

[0194] In formula (B9), R43 is a halogen atom other than fluorine, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples may be listed as those exemplified in the description of formula (A) for hydrocarbon groups represented by R1, but are not limited to these. Furthermore, when h3 is 2, 3, or 4, each R43 can be the same or different.

[0195] Furthermore, when h3 is 2, 3, or 4, the complex R43 can also bond with each other and form a ring together with the carbon atoms they bond to. Specific examples of the rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, and adamantane rings. Also, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms. Similarly, some of the -CH2- groups in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. As a result, the rings 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)-), and haloalkyl groups.

[0196] Specific examples of the anion of repeating unit B7 can be listed as shown below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above, and Me is a methyl group. [Chemistry 102]

[0197] [Chemistry 103]

[0198] [Chemistry 104]

[0199] [Chemistry 105]

[0200] [Chemistry 106]

[0201] [Chemistry 107]

[0202] [Chemistry 108]

[0203] [Chemistry 109]

[0204] [Chemical 110]

[0205] [Chemistry 111]

[0206] [Chemistry 112]

[0207] [Chemistry 113]

[0208] [Chemistry 114]

[0209] Specific examples of the anion in repeating unit B8 can be listed as shown below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 115]

[0210] [Chemistry 116]

[0211] [Chemistry 117]

[0212] [Chemistry 118]

[0213] [Chemistry 119]

[0214] [Chemistry 120]

[0215] [Chemistry 121]

[0216] [Chemistry 122]

[0217] [Chemistry 123]

[0218] [Chemistry 124]

[0219] [Chemistry 125]

[0220] Specific examples of the anion in repeating unit B9 can be listed as shown below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 126]

[0221] [Chemistry 127]

[0222] [Chemistry 128]

[0223] [Chemistry 129]

[0224] [Chemistry 130]

[0225] [Chemistry 131]

[0226] [Chemistry 132]

[0227] [Chemistry 133]

[0228] [Chemistry 134]

[0229] [Chemistry 135]

[0230] [Chemistry 136]

[0231] [Chemistry 137]

[0232] [Chemistry 138]

[0233] [Chemistry 139]

[0234] [Chemistry 140]

[0235] [Chemistry 141]

[0236] [Chemistry 142]

[0237] Specific examples of anions in the repeating unit B10 can be listed as shown below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 143]

[0238] In equations (B7) to (B10), A+ represents onium cations. Regarding the aforementioned onium cations, it is more ideal to use strontium cations represented by equation (Z-1) or monium cations represented by equation (Z-2). [Chemistry 144]

[0239] In formulas (Z-1) and (Z-2), Rct1 to Rct5 are each independently a halogen atom, or may contain a hydrocarbon group with 1 to 30 carbon atoms of heteroatoms.

[0240] Specific examples of halogen atoms represented by Rct1 to Rct5 include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0241] Rct1 to Rct5 represent hydrocarbon groups, which 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, dibutyl, and tributyl; 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; and aralkyl groups with 7 to 30 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl. Combinations of these groups to obtain aryl groups are preferred. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Similarly, the -CH2- part of the aforementioned hydrocarbon group can be replaced by a group 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.

[0242] Furthermore, Rct1 and Rct2 can also bond to each other and form a ring together with the sulfur atoms they are bonded to. In this case, specific examples of the aforementioned ring structures can be listed as follows. [Chemistry 145] In the formula, the dashed lines represent atomic bonds with Rct3.

[0243] Regarding specific examples of strontium cations represented by formula (Z-1), examples include those described in paragraphs

[0102] to

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

[0070] to

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

[0244] Regarding specific examples of citric acid represented by formula (Z-2), those described in paragraph

[0181] of Japanese Patent Application Publication No. 2024-000259 can be cited, but are not limited to these.

[0245] For the onium cation represented by Z+, the strontium cation represented by the following formula (Z-3) is also more ideal. [Chemistry 146]

[0246] 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, a benzene ring with m1 = 0 is more ideal. 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, a benzene ring with m2 = 0 is more ideal. 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, a benzene ring with m3 = 0 is more ideal.

[0247] In formula (Z-3), m4 is 0, 1, 2, 3, or 4. The more iodine atoms in the cation structure, the higher the absorption, especially for EUV. However, there is a concern that the solvent solubility will be reduced and the inhibitor will precipitate in the composition. Therefore, m4 is more ideal if it is 0, 1, 2, or 3, and even more ideal if it is 0, 1, or 2.

[0248] In formula (Z-3), m5 can be 0, 1, 2, 3, or 4. Considering the supply of raw materials, m5 being 0, 1, 2, or 3 is more ideal, with 0, 1, or 2 being even more ideal. m6 can be 0, 1, 2, 3, 4, 5, or 6. Considering the supply of raw materials, m6 being 0, 1, 2, or 3 is more ideal, with 0, 1, or 2 being even more ideal. m7 can be 0, 1, 2, 3, 4, 5, or 6. Considering the supply of raw materials, m7 being 0, 1, 2, or 3 is more ideal, with 0, 1, or 2 being even more ideal.

[0249] In equation (Z-3), m8 can be 0, 1, or 2. Considering raw material supply, m8 being 0 or 1 is more ideal. m9 can be 0, 1, or 2. Considering raw material supply, m9 being 0 or 1 is more ideal. m10 can be 0, 1, or 2. Considering raw material supply, m10 being 0 or 1 is more ideal.

[0250] 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 the solubility of the solvent, a benzene ring with m11 of 0 is more ideal.

[0251] In formula (Z-3), m12 is 0, 1, 2, 3, or 4. The more iodine atoms in the cation structure, the higher the absorption, especially for EUV. However, there is a concern that the solvent solubility will be reduced and the iodine will precipitate in the inhibitor composition. Therefore, m12 is more ideal if it is 0, 1, 2, or 3, and even more ideal if it is 0, 1, or 2.

[0252] In equation (Z-3), m13 is 0, 1, or 2. From the perspective of raw material supply, m13 being 0 or 1 is more ideal. m14 is 0, 1, or 2. From the perspective of synthesis, m14 being 0 or 1 is more ideal.

[0253] 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.

[0254] In formula (Z-3), RF1 to RF3 are each independently a fluorine atom, a fluorinated saturated hydrocarbon group with 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon oxygen group with 1 to 6 carbon atoms, or a fluorinated saturated hydrocarbon thio group with 1 to 6 carbon atoms. Among these, trifluoromethyl, trifluoromethoxy, and trifluorothiomethoxy are more ideal. When m5 is 2 or more, each RF1 can be the same or different from each other; when m6 is 2 or more, each RF2 can be the same or different from each other; when m7 is 2 or more, each RF3 can be the same or different from each other.

[0255] In formula (Z-3), Rct6 to Rct9 are halogen atoms other than iodine and fluorine atoms, nitro groups, cyano groups, and may also contain hydrocarbon groups with 1 to 20 carbon atoms containing heteroatoms, hydroxyl groups with 1 to 20 carbon atoms containing heteroatoms, or hydrocarbon thiol groups with 1 to 20 carbon atoms containing heteroatoms. The hydrocarbon groups, hydroxyl groups, and hydrocarbon thiol groups mentioned above can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed as those identical to those exemplified in the description of formula (A) for the hydrocarbon group represented by R1. Furthermore, some or all of the hydrogen atoms in the hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon sulfur group mentioned above can be replaced by a group containing heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, and halogen atom. The -CH2- part of the aforementioned hydrocarbon group can also be replaced by a group containing heteroatoms such as oxygen atom, sulfur atom, and nitrogen atom. As a result, it may contain hydroxyl group, cyano group, fluorine atom, chlorine atom, bromine atom, iodine atom, carbonyl group, ether bond, ester bond, sulfonate bond, carbonate bond, lactone ring, sulfonolactone ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl group, etc.

[0256] Furthermore, when m8 is 2, the two Rct6 atoms can be identical or different, and they can also bond together to form a ring with the carbon atoms they are bonded to. When m9 is 2, the two Rct7 atoms can be identical or different, and they can also bond together to form a ring with the carbon atoms they are bonded to. When m10 is 2, the two Rct8 atoms can be identical or different, and they can also bond together to form a ring with the carbon atoms they are bonded to. When m13 is 2, the two Rct9 atoms can be identical or different, and they can also bond together to form a ring with the carbon atoms they are bonded to. Specific examples of the rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norcamphene rings, and adamantane rings. Furthermore, some or all of the hydrogen atoms in the aforementioned ring can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Similarly, the -CH2- group in the aforementioned ring can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may also 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, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0257] Furthermore, the aromatic rings of S+ in the strontium cation represented by formula (Z-3) can also bond to each other and form a ring together with S+. In this case, specific examples of the aforementioned ring structures can be listed as follows. [Chemistry 147] In the formula, the dashed lines represent atomic bonds.

[0258] In formula (Z-3), LB and LC are each independently a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. Among these, for LB, a single bond, ether bond, ester bond, or sulfonate bond is more ideal, and an ester bond or sulfonate bond is even more ideal. For LC, a single bond, ether bond, or ester bond is more ideal, and a single bond is even more ideal.

[0259] In formula (Z-3), XL is a single bond, or may contain a heteroatom and be a carbon group with 1 to 40 carbon atoms. The aforementioned carbon group can be linear, branched, or cyclic; specific examples include alkyldiyl, cyclic saturated carbon groups, and aryl groups. Specific examples of the aforementioned heteroatom include oxygen atoms, nitrogen atoms, and sulfur atoms.

[0260] Specific examples of XL-denoted hydrocarbon groups containing 1 to 40 carbon atoms can be listed below, but are not limited to these. Additionally, in the following formulas, * represent atomic bonds with LB and LC, respectively. [Chemistry 148]

[0261] [Chemistry 149]

[0262] [Chemistry 150]

[0263] [Chemistry 151]

[0264] Among these, XL-0~XL-22, XL-29~XL-34, and XL-47~XL-58 are more ideal.

[0265] For strontium cations represented by formula (Z-3), those represented by formula (Z-3-1) are more ideal. [Chemistry 152] In the formula, m4~m10, m12~m14, RF1~RF3, Rct6~Rct9, LB, LC and XL series are the same as those mentioned above.

[0266] For strontium cations represented by formula (Z-3-1), those represented by formula (Z-3-2) are more ideal. [Chemistry 153] In the formula, m4~m10, RF1~RF3 and Rct6~Rct8 are the same as those mentioned above.

[0267] Specific examples of strontium cations represented by formula (Z-3) are shown below, but are not limited to these. Additionally, in the following formula, Me is a methyl group. [Chemistry 154]

[0268] [Chemistry 155]

[0269] [Chemistry 156]

[0270] [Chemistry 157]

[0271] [Chemistry 158]

[0272] [Chemistry 159]

[0273] [Chemistry 160]

[0274] [Chemistry 161]

[0275] [Chemistry 162]

[0276] [Chemistry 163]

[0277] [Chemistry 164]

[0278] [Chemistry 165]

[0279] [Chemistry 166]

[0280] [Chemistry 167]

[0281] [Chemistry 168]

[0282] [Chemistry 169]

[0283] [Chemistry 170]

[0284] [Chemistry 171]

[0285] [Chemistry 172]

[0286] [Chemistry 173]

[0287] [Chemistry 174]

[0288] [Chemistry 175]

[0289] [Chemistry 176]

[0290] [Chemistry 177]

[0291] [Chemistry 178]

[0292] [Chemistry 179]

[0293] [Chemistry 180]

[0294] [Chemistry 181]

[0295] Regarding the specific structure of repeating units B6 to B10, any combination of anions and cations as described above can be listed.

[0296] Repeating units B6-B10 are units that generate acid when exposed to high-energy rays. It is believed that by including these units in the polymer, acid diffusion is moderately suppressed, resulting in a pattern with reduced LER (Leakage Rate). Furthermore, it is believed that by including these units in the polymer, the phenomenon of acid evaporation from the exposed areas and re-adhesion to the unexposed areas during vacuum baking is suppressed, thus effectively reducing LER and minimizing shape degradation caused by undesirable film loss in the unexposed areas.

[0297] Among repeating units B6 to B10, which are more ideal for processing blank photomasks, repeating units B7 to B10 are more ideal in terms of suppressing acid diffusion and the most appropriate acid strength on the acid-instable groups of the polymer, while repeating units B8, B9 and B10 are even more ideal.

[0298] Among all the repeating units B6 to B10 in the aforementioned polymer, it is ideal to introduce them in the range of 0.1 to 30 mol%, and even more ideally in the range of 0.5 to 20 mol%. Repeating units B6 to B10 can be used alone or in combination of two or more.

[0299] Among all repeating units of the aforementioned polymer, it is ideal for the content of repeating units with an aromatic ring skeleton to be 65 mol% or more, more ideal for 75 mol% or more, and even more ideal for 85 mol% or more. When repeating units B6 to B10 are not present, it is ideal for all units to have an aromatic ring skeleton.

[0300] 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.

[0301] Regarding the aforementioned example of (meth)acrylate units with adhesion groups, examples 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. [Chemistry 182]

[0302] In formulas (B11) to (B13), RA is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R51 is -O- or a methylene group. R52 is a hydrogen atom or a hydroxyl group. R53 is a saturated hydrocarbon group with 1 to 4 carbon atoms. i is 0, 1, 2, or 3.

[0303] When repeating units B11 to B13 are included, their content is ideally 0 to 20 mol% among all repeating units in the aforementioned polymer, and even more ideally 0 to 10 mol%. Repeating units B11 to B13 can be used alone or in combination of two or more.

[0304] The aforementioned polymer can be synthesized by copolymerizing the monomers protected by protecting groups as needed using known methods, followed by a deprotection reaction as required. The copolymerization reaction is not particularly limited, but free radical polymerization and anionic polymerization are preferred. Japanese Patent Application Publication No. 2004-115630 can be referenced regarding these methods.

[0305] Ideally, the weight-average molecular weight (Mw) of the aforementioned polymer should be between 1,000 and 50,000, with 2,000 to 20,000 being even more ideal. If Mw is above 1,000, the previously known phenomenon of pattern head rounding leading to reduced resolution and LER degradation will not occur. On the other hand, if Mw is below 50,000, LER degradation will not occur, especially when forming patterns with a linewidth of 100 nm or less. Furthermore, in this invention, Mw is a polystyrene conversion value determined using a gel permeation chromatography (GPC) instrument with THF or DMF as solvent.

[0306] The aforementioned polymer has a molecular weight distribution (Mw / Mn) of 1.0~2.0, which is more ideally 1.0~1.9, and even more ideally a narrow dispersion of 1.0~1.8. In such a narrow dispersion case, no foreign matter will be generated on the pattern after development, and the shape of the pattern will not deteriorate.

[0307] Furthermore, regarding the aforementioned basic polymer design, a dissolution rate of 10 nm / min or less for alkaline developer is ideal, 7 nm / min or less is even more ideal, and 5 nm / min or less is the best. In advanced generations, when the coating film on the substrate is in the thin film domain (below 100 nm), the impact on pattern 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 significant in the fabrication of photomasks requiring defect-free results, due to the tendency for strong development processes. Furthermore, the dissolution rate of the basic polymer in the alkaline developer in this invention is calculated from the film loss when a polymer solution (polymer concentration: 16.7% by mass, solvent: propylene glycol monomethyl ether acetate (PGMEA)) is spin-coated onto an 8-inch silicon wafer, baked at 100°C for 90 seconds to form a film with a thickness of 1000 nm, and then developed at 23°C for 100 seconds with a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.

[0308] (B) The base polymer of the component may also contain other polymers besides those mentioned above. Regarding other polymers, previously known base polymers used as inhibitor components may be used. The content of other polymers is not particularly limited, as long as it does not impair the effects of the present invention.

[0309] [(C) Organic solvent] The inhibitor composition of the present invention may also contain an organic solvent as component (C). Regarding the aforementioned organic solvent, there is no particular limitation as long as it is capable of dissolving each component. Examples of such organic solvents include 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), ethyl acetate, acetone ... Ethers such as 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, tributyl acetate, tributyl propionate, and propylene glycol monobutyl ether acetate; lactones such as γ-butyrolactone; and mixed solvents thereof. When using the unstable acid group of an acetal system, a high-boiling-point alcohol solvent, specifically diethylene glycol, propylene glycol, glycerol, 1,4-butanediol, and 1,3-butanediol, can be added to accelerate the deprotection reaction of the acetal.

[0310] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, PGME, cyclohexanone, EL, γ-butyrolactone, and their mixtures are more ideal.

[0311] When the chemical amplification positive inhibitor composition of the present invention contains (C) an organic solvent, its content is ideally 200-10000 parts by mass relative to 80 parts by mass of the (B) base polymer, and even more ideally 400-5000 parts by mass. (C) The organic solvent can be used alone or in combination of two or more.

[0312] [(D) Photoacid generator] The chemical amplification positive inhibitor composition of the present invention may also contain a photoacid generator as component (D). Regarding the aforementioned photoacid generator, there is no particular limitation as long as it is a compound that produces acid upon irradiation by high-energy rays. Ideal photoacid generators include strontium salts, ferrous salts, sulfonyldiazomethane, N-sulfonyloxyimide, and oxime-O-sulfonate type acid generators.

[0313] Specific examples of the aforementioned photoacid generators include nonafluorobutane sulfonate ions, partially fluorinated sulfonate ions described in paragraphs

[0247] to

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

[0261] to

[0265] of Japanese Patent Application Publication No. 2008-111103, and those described in paragraphs

[0122] to

[0142] and

[0080] to

[0081] of Japanese Patent Application Publication No. 2010-215608. Among the aforementioned specific examples, photoacid generators of the aromatic sulfonate ion type or alkane sulfonate ion type are particularly ideal because they generate acids of appropriate strength for deprotecting the unstable acid group of the repeating unit B2.

[0314] For this type of photoacid generator, the following salt compounds containing anions are more ideal. [Chemistry 183]

[0315] [Chemistry 184]

[0316] [Chemistry 185]

[0317] [Chemistry 186]

[0318] [Chemistry 187]

[0319] [Chem.188]

[0320] [Chemistry 189]

[0321] [Chemistry 190]

[0322] [Chemistry 191]

[0323] [Chemistry 192]

[0324] [Chemistry 193]

[0325] [Chemistry 194]

[0326] [Chemistry 195]

[0327] [Chemistry 196]

[0328] [Chemistry 197]

[0329] [Chemistry 198]

[0330] [Chemistry 199]

[0331] [Chemistry 200]

[0332] [Chemical Engineering 201]

[0333] [Chemical Engineering 202]

[0334] [Chemical Engineering 203]

[0335] [Chemical 204]

[0336] [Chemical Engineering 205]

[0337] [Chemical Engineering 206]

[0338] [Chemical 207]

[0339] [Chemical Engineering 208]

[0340] [Chemical Engineering 209]

[0341] [Chemical 210]

[0342] [Chemistry 211]

[0343] [Chemistry 212]

[0344] [Chemistry 213]

[0345] [Chemistry 214]

[0346] [Chemical 215]

[0347] [Chemistry 216]

[0348] [Chemistry 217]

[0349] [Chemistry 218]

[0350] [Chemistry 219]

[0351] [Chem.220]

[0352] [Chemistry 221]

[0353] [Chemistry 222]

[0354] [Chemistry 223]

[0355] [Chemistry 224]

[0356] [Chemistry 225]

[0357] [Chemistry 226]

[0358] [Chemistry 227]

[0359] [Chemistry 228]

[0360] [Chemistry 229]

[0361] [Chemistry 230]

[0362] [Chemistry 231]

[0363] [Chemistry 232]

[0364] [Chemistry 233]

[0365] [Chemistry 234]

[0366] [Chemistry 235]

[0367] [Chemistry 236]

[0368] [Chemistry 237]

[0369] [Chemistry 238]

[0370] [Chemistry 239]

[0371] [Chemistry 240]

[0372] [Chemistry 241]

[0373] [Chemistry 242]

[0374] [Chemistry 243]

[0375] [Chemistry 244]

[0376] [Chemistry 245]

[0377] [Chemistry 246]

[0378] [Chemistry 247]

[0379] [Chemistry 248]

[0380] [Chemistry 249]

[0381] [Chemistry 250]

[0382] [Chemistry 251]

[0383] [Chemistry 252]

[0384] [Chemistry 253]

[0385] [Chemistry 254]

[0386] [Chemistry 255]

[0387] [Chemistry 256]

[0388] [Chemistry 257]

[0389] [Chemistry 258]

[0390] [Chemistry 259]

[0391] [Chemistry 260]

[0392] [Chemistry 261]

[0393] [Chemistry 262]

[0394] [Chemistry 263]

[0395] [Chemistry 264]

[0396] [Chemistry 265]

[0397] [Chemistry 266]

[0398] [Chemistry 267]

[0399] [Chemistry 268]

[0400] [Chemistry 269]

[0401] [Chemistry 270]

[0402] [Chemistry 271]

[0403] [Chemistry 272]

[0404] [Chemistry 273]

[0405] [Chemistry 274]

[0406] [Chemistry 275]

[0407] [Chemistry 276]

[0408] [Chemistry 277]

[0409] [Chemistry 278]

[0410] [Chemistry 279]

[0411] [Chemistry 280]

[0412] [Chemistry 281]

[0413] [Chemistry 282]

[0414] [Chemistry 283]

[0415] [Chemistry 284]

[0416] [Chemistry 285]

[0417] [Chemistry 286]

[0418] [Chemistry 287]

[0419] [Chemistry 288]

[0420] [Chemistry 289]

[0421] [Chemistry 290]

[0422] [Chemistry 291]

[0423] [Chemistry 292]

[0424] [Chemistry 293]

[0425] [Chemistry 294]

[0426] [Chemistry 295]

[0427] [Chemistry 296]

[0428] [Chemistry 297]

[0429] [Chemistry 298]

[0430] [Chemistry 299]

[0431] [Chemical 300]

[0432] [Chemical Engineering 301]

[0433] [Chemical 302]

[0434] [Chemical 303]

[0435] [Chemical 304]

[0436] [Chemical 305]

[0437] [Chemical 306]

[0438] [Chemical 307]

[0439] [Chemical 308]

[0440] [Chemical 309]

[0441] [Chemical 310]

[0442] [Chemistry 311]

[0443] [Chemistry 312]

[0444] [Chemistry 313]

[0445] [Chemical 314]

[0446] [Chemical 315]

[0447] [Chemistry 316]

[0448] [Chemistry 317]

[0449] [Chemistry 318]

[0450] [Chemistry 319]

[0451] [Chemistry 320]

[0452] [Chemistry 321]

[0453] [Chemistry 322]

[0454] [Chemistry 323]

[0455] [Chemistry 324]

[0456] [Chemistry 325]

[0457] [Chemistry 326]

[0458] [Chemistry 327]

[0459] [Chemistry 328]

[0460] [Chemistry 329]

[0461] [Chemistry 330]

[0462] [Chemistry 331]

[0463] [Chemistry 332]

[0464] [Chemistry 333]

[0465] [Chemistry 334]

[0466] [Chemistry 335]

[0467] [Chemistry 336]

[0468] [Chemistry 337]

[0469] [Chemistry 338]

[0470] [Chemistry 339]

[0471] [Transformation 340]

[0472] [Chemistry 341]

[0473] [Chemistry 342]

[0474] [Chemistry 343]

[0475] [Chemistry 344]

[0476] [Chemistry 345]

[0477] [Chemistry 346]

[0478] [Chemistry 347]

[0479] [Chemistry 348]

[0480] [Chemistry 349]

[0481] [Chemical 350]

[0482] [Chemistry 351]

[0483] [Chemistry 352]

[0484] [Chemistry 353]

[0485] [Chemical Formula 354]

[0486] [Chemical Formula 355]

[0487] [Chemical Formula 356]

[0488] [Chemical Formula 357]

[0489] [Chemical Formula 358]

[0490] [Chemical Formula 359]

[0491] [Chemical Formula 360]

[0492] [Chemical Formula 361]

[0493] [Chemical Formula 362]

[0494] [Chemical Formula 363]

[0495] [Chemical Formula 364]

[0496] [Chemical Formula 365]

[0497] [Chemical Formula 366]

[0498] [Chemical Formula 367]

[0499] [Chem.368]

[0500] [Chemistry 369]

[0501] [Transformation 370]

[0502] [Chemistry 371]

[0503] [Chemistry 372]

[0504] [Chemistry 373]

[0505] [Chemistry 374]

[0506] [Chemistry 375]

[0507] [Chemistry 376]

[0508] [Chemistry 377]

[0509] [Chemistry 378]

[0510] [Chemistry 379]

[0511] [Chemistry 380]

[0512] [Chemistry 381]

[0513] [Chemistry 382]

[0514] [Chemistry 383]

[0515] [Chem. 384]

[0516] [Chem. 385]

[0517] [Chemistry 386]

[0518] [Chemistry 387]

[0519] [Chem.388]

[0520] [Chemistry 389]

[0521] [Chemistry 390]

[0522] [Chemistry 391]

[0523] [Chemistry 392]

[0524] [Chemistry 393]

[0525] [Chem. 394]

[0526] [Chemistry 395]

[0527] [Chemistry 396]

[0528] [Chemistry 397]

[0529] [Chemistry 398]

[0530] [Chemistry 399]

[0531] [Chemical 400]

[0532] [Chemical Engineering 401]

[0533] [Chemical 402]

[0534] [Chemical 403]

[0535] [Chemical 404]

[0536] [Chemical 405]

[0537] [Chemical 406]

[0538] [Chemical 407]

[0539] [Chemical 408]

[0540] [Chemical 409]

[0541] [Chemical 410]

[0542] [Chemistry 411]

[0543] [Chemistry 412]

[0544] [Chemistry 413]

[0545] [Chemistry 414]

[0546] [Chemical 415]

[0547] [Chemistry 416]

[0548] [Chemistry 417]

[0549] [Chemistry 418]

[0550] [Chemistry 419]

[0551] [Chem.420]

[0552] [Chemistry 421]

[0553] [Chemistry 422]

[0554] [Chemistry 423]

[0555] [Chemistry 424]

[0556] Furthermore, regarding the aforementioned photoacid generator, a salt compound containing an anion represented by the following formula (D1) is also more ideal. [Chemical 425]

[0557] In equation (D1), p1 is 1, 2, or 3. p2 is 1, 2, 3, 4, or 5. p3 is 0, 1, 2, or 3. Only 1 ≤ p2 + p3 ≤ 5. q1 is 0 or 1.

[0558] In formula (D1), L21 is a single bond, ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond.

[0559] In formula (D1), L22 is an ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond.

[0560] In formula (D1), LD is a single bond or an extended hydrocarbon group with 1 to 20 carbon atoms when p1 is 1, and a (p1+1) valence hydrocarbon group with 1 to 20 carbon atoms when p1 is 2 or 3. The extended hydrocarbon group and the (p1+1) valence hydrocarbon group may also contain at least one selected from ether bond, carbonyl group, ester bond, amide bond, sulfonyl lactone ring, amide ring, carbonate bond, halogen atom, hydroxyl group and carboxyl group.

[0561] LD represents a hydrocarbon group with 1 to 20 carbon atoms, which 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 methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl; cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms, such as cyclopentanediyl, cyclohexanediyl, norcamphenediyl, and adamantanediyl; unsaturated aliphatic hydrocarbon 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 naphthyl; and groups obtained by combining them. Furthermore, LD represents a (p1+1) valence hydrocarbon group with 1 to 20 carbon atoms, which can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include groups obtained by removing one or two hydrogen atoms from the aforementioned examples of hydrocarbon groups with 1 to 20 carbon atoms.

[0562] In formula (D1), Rf21 and Rf22 are each 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.

[0563] In formula (D1), R101 is 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, -N(R101A)(R101B), -N(R101C)-C(=O)-R101D, or -N(R101C)-C(=O)-O-R101D. R101A and R101B are each independently a hydrogen atom or a saturated hydrocarbon group with 1 to 6 carbon atoms. R101C is a hydrogen atom or a saturated hydrocarbon group with 1 to 6 carbon atoms. R101D is a saturated hydrocarbon group with 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group with 2 to 8 carbon atoms.

[0564] R101, R101A, R101B, and R101C represent saturated hydrocarbon groups with 1 to 6 carbon atoms, which 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, dibutyl, tributyl, n-pentyl, and n-hexyl; and cyclic saturated hydrocarbon groups with 3 to 6 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Furthermore, regarding the saturated hydrocarbon base of the saturated hydrocarbon oxygen group with 1 to 6 carbon atoms represented by R101, examples similar to the aforementioned specific examples of saturated hydrocarbon groups can be listed. Regarding the saturated hydrocarbon base of the saturated hydrocarbon carbonyl oxygen group with 2 to 6 carbon atoms represented by R101, examples with 1 to 5 carbon atoms can be listed, as in the aforementioned specific examples of saturated hydrocarbon groups with 1 to 6 carbon atoms.

[0565] R101D represents unsaturated aliphatic hydrocarbon groups with 2 to 8 carbon atoms, which 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.

[0566] In formula (D1), R102 is a saturated hydrocarbon group with 1 to 20 carbon atoms or an aryl group with 6 to 20 carbon atoms. Some or all of the hydrogen atoms of the saturated hydrocarbon group may be replaced by halogen atoms other than fluorine atoms. 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.

[0567] R102 represents an extended hydrocarbon group with 1 to 20 carbon atoms, which can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed as those exemplified in relation to the extended hydrocarbon group with 1 to 20 carbon atoms represented by LB.

[0568] In terms of specific examples of elongated aryl groups with carbon numbers 6~20 represented by R10 2 , such as elongenyl, ephrenyl, phenanthrene, and anthracene diyls may be enumerated. The saturated hydrocarbon groups with carbon numbers 1~20 of the substituents of the aforementioned elongated groups and the hydrocarbon bases with carbon numbers 1~20 may be straight chain, branched, or cyclic cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, rhododendyl, amantadyl and other alkyl groups with carbon numbers 1~20. In terms of specific examples of elongated aryl groups with carbon numbers 6~14 of the substituents of the aforementioned elongated aryl groups, they may be enumerated such as elongenyl, elongate, phenanthrene, and anthracene.

[0569] In terms of the anions represented by formula (D1), the anions represented by the following formula (D2) are more ideal. 426

[0570] In formula (D2), p1, p2, p3, L21, LD and R101 are the same as previously described. q2 is 1, 2, 3, or 4. R102A is a saturated hydrocarbon group with carbon numbers 1~20, a saturated hydrocarbon oxygen group with carbon numbers 1~20, an aryl group with carbon numbers 6~14, a halogen atom, or a hydroxyl group. In addition, when q2 is 2, 3, or 4, each R102A can be identical or different from each other.

[0571] In the case of specific examples of anions represented by Equation (D1), those may be enumerated as shown below, but are not limited to these. 427

[0572] 428

[0573] 429

[0574] 430

[0575] [Chemistry 431]

[0576] [Chemistry 432]

[0577] [Chemistry 433]

[0578] [Chemistry 434]

[0579] [Chemistry 435]

[0580] [Chemistry 436]

[0581] [Chemistry 437]

[0582] [Chemistry 438]

[0583] [Chemistry 439]

[0584] [Chemistry 440]

[0585] [Chemistry 441]

[0586] [Chemistry 442]

[0587] [Chemistry 443]

[0588] [Chemistry 444]

[0589] [Chemistry 445]

[0590] [Chemistry 446]

[0591] [Chemistry 447]

[0592] [Chemistry 448]

[0593] [Chemistry 449]

[0594] [Chemistry 450]

[0595] [Chemistry 451]

[0596] [Chemistry 452]

[0597] [Chemistry 453]

[0598] [Chemistry 454]

[0599] [Chemistry 455]

[0600] [Chemistry 456]

[0601] [Chemistry 457]

[0602] [Chemistry 458]

[0603] [Chemistry 459]

[0604] [Chemistry 460]

[0605] [Chemistry 461]

[0606] [Chemistry 462]

[0607] [Chemistry 463]

[0608] (D) In ​​the photoacid generating agent, strontium cations or ferrophosphate cations are preferred as the cations paired with the aforementioned anions. Specific examples of strontium cations may include those identical to those exemplified by strontium cations represented by formulas (Z-1) and (Z-3), but are not limited to these. Specific examples of ferrophosphate cations may include those identical to those exemplified by ferrophosphate cations represented by formula (Z-2), but are not limited to these.

[0609] For the acids produced by the aforementioned photoacid generators, a pKa of -2.0 or higher is ideal, and -1.0 or higher is even more desirable. Furthermore, an upper limit of 2.0 for the pKa is preferred. The pKa values ​​were calculated using the pKa DB function in ACD / Chemsketch ver: 9.04, software developed by Advanced Chemistry Development, Inc.

[0610] When the chemical amplification positive resist composition of the present invention includes a (D) photoacid generator, its content is ideally 1 to 10 parts by mass relative to 80 parts by mass of the aforementioned base polymer, and more ideally 1 to 5 parts by mass. By including the (D) photoacid generator, the amount of acid generated in the exposed portion and the dissolution inhibition performance of the unexposed portion can be appropriately adjusted. One type of (D) photoacid generator can be used alone, or two or more can be used in combination.

[0611] When the chemically amplified positive resist composition of the present invention simultaneously contains (D) a photoacid generator and (A) a quencher, the content ratio of the photoacid generator to the quencher (photoacid generator / quencher) is preferably less than 3 by mass, more preferably less than 2.5, and even more preferably less than 2. If the aforementioned content ratio of the photoacid generator to the quencher contained in the chemically amplified positive resist composition falls within the aforementioned range, acid diffusion can be sufficiently suppressed, and excellent resolution and dimensional uniformity can be obtained.

[0612] [(E) Polymers containing fluorine atoms] The chemically amplified positive resist composition of this invention aims to: enhance contrast, suppress chemical flare of acids during high-energy ray irradiation, shield the mixing of acids from the antistatic film during the coating process of the antistatic film material onto the resist film, and suppress unintended pattern degradation. As component (E), it may also contain a polymer containing at least one of the repeating units represented by formula (E1) (hereinafter also referred to as repeating unit E1.), repeating units represented by formula (E2) (hereinafter also referred to as repeating unit E2.), repeating units represented by formula (E3) (hereinafter also referred to as repeating unit E3.), and repeating units represented by formula (E4) (hereinafter also referred to as repeating unit E4.). Because the aforementioned polymer containing fluorine atoms also functions as a surfactant, it can prevent the re-adhesion of insoluble substances generated during the development process onto the substrate, thus also effectively addressing development defects. [Chemistry 464]

[0613] In formulas (E1) to (E4), k is 1, 2, or 3. RB are each independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R201, R202, R204, and R205 are each independently a hydrogen atom or a saturated hydrocarbon group with 1 to 10 carbon atoms. R203, R206, R207, and R208 are each independently a hydrogen atom, a hydrocarbon group with 1 to 15 carbon atoms, a fluorinated hydrocarbon group with 1 to 15 carbon atoms, or an acid-unstable group. When R203, R206, R207, and R208 are hydrocarbon groups or fluorinated hydrocarbon groups, an ether bond or a carbonyl group may also be present between the carbon-carbon bonds. Z1 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.

[0614] R201, R202, R204, and R205 represent saturated hydrocarbon groups with 1 to 10 carbon atoms, which 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, dibutyl, tributyl, 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.

[0615] R203, R206, R207, and R208 represent hydrocarbon groups with 1 to 15 carbon atoms, which 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 with 1 to 15 carbon atoms being preferred. Regarding the aforementioned alkyl groups, in addition to those mentioned above, examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, and n-pentadecanyl. Furthermore, regarding fluorinated hydrocarbon groups, examples include groups formed by replacing some or all of the hydrogen atoms of the carbon atoms bonded to the aforementioned hydrocarbon groups with fluorine atoms.

[0616] Regarding Z1 as a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms, examples include groups formed by removing k hydrogen atoms from an alkyl group with 1 to 20 carbon atoms or a cyclic saturated hydrocarbon group with 3 to 20 carbon atoms. Furthermore, regarding Z1 as a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms, examples include groups formed by replacing at least one hydrogen atom of the aforementioned (k+1) valence hydrocarbon group with a fluorine atom.

[0617] Specific examples of repeating units E1 to E4 can be listed as shown below, but are not limited to these. Furthermore, in the following formula, RB is the same as described above. [Chemistry 465]

[0618] [Chemistry 466]

[0619] [Chemistry 467]

[0620] Furthermore, it is preferable that the aforementioned fluorine-containing polymers include 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.). [Chemistry 468]

[0621] In formulas (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. RC are each independently a hydrogen atom or a methyl group. R209 is a hydrogen atom, or a linear or branched hydrocarbon group with 1 to 5 carbon atoms, which may have a heteroatom-containing group between carbon-carbon bonds. R210 is a linear or branched hydrocarbon group with 1 to 5 carbon atoms, which may have a heteroatom-containing group between carbon-carbon bonds. R211 is a saturated hydrocarbon group with 1 to 20 carbon atoms, formed by replacing at least one hydrogen atom with a fluorine atom. The -CH2- part of the aforementioned saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. Z2 is a single bond, *-C(=O)-O-, or *-C(=O)-NH-. Z3 is a single bond, -O-, *-C(=O)-O-Z31-Z32-, or *-C(=O)-NH-Z31-Z32-. Z31 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms. Z32 is a single bond, ester bond, ether bond, or sulfonamide bond. * indicates an atomic bond with a carbon atom in the main chain.

[0622] For hydrocarbon groups with 1 to 5 carbon atoms represented by R209 and R210, examples include alkyl, alkenyl, and ynyl groups, with alkyl being the most desirable. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, and n-pentyl. Furthermore, the carbon-carbon bonds of the aforementioned hydrocarbon groups can also be separated by heteroatoms such as oxygen, sulfur, and nitrogen atoms.

[0623] In formula (E5), it is ideal for -OR209 to be a hydrophilic group. In this case, for R209, it is ideal for it to be a hydrogen atom or an alkyl group with 1 to 5 carbon atoms separated by oxygen atoms.

[0624] R211 represents a saturated hydrocarbon group with 1 to 20 carbon atoms formed by replacing at least one hydrogen atom with a fluorine atom. It can be linear, branched, or cyclic. For specific examples, it can be formed by replacing at least one hydrogen atom with a fluorine atom in an alkyl group with 1 to 20 carbon atoms or a cyclic saturated hydrocarbon group with 3 to 20 carbon atoms.

[0625] Z2 is preferably *-C(=O)-O- or *-C(=O)-NH-. Furthermore, RC is preferably methyl. The presence of a carbonyl group in Z2 enhances the acid capture ability of the antistatic film. Also, if RC is methyl, it becomes a rigid polymer with a higher glass transition temperature (Tg), thus inhibiting acid diffusion. This results in a resistive film with good long-term stability, and the resolution and pattern shape will not deteriorate.

[0626] Z3 represents a saturated extended hydrocarbon group with 1 to 10 carbon atoms, which can be straight-chain, 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, and 1,1-dimethylethane-1,2-diyl.

[0627] Regarding the repeating unit E5, examples as shown below can be listed, but it is not limited to these. Furthermore, in the following formula, the RC system is the same as described above. [Chemistry 469]

[0628] [Chemistry 470]

[0629] Regarding the repeating unit E6, examples as shown below can be listed, but it is not limited to these. Furthermore, in the following formula, the RC system is the same as described above. [Chemistry 471]

[0630] [Chemistry 472]

[0631] [Chemistry 473]

[0632] [Chemistry 474]

[0633] The content of repeating units E1 to E4 is ideally 15 to 95 mol%, and more ideally 20 to 85 mol%, among all repeating units in the aforementioned polymers containing fluorine atoms. The content of repeating units E5 and / or E6 is ideally 5 to 85 mol%, and more ideally 15 to 80 mol%, among all repeating units in the aforementioned polymers containing fluorine atoms. Repeating units E1 to E6 can be used individually or in combination of two or more.

[0634] (E) Polymers 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 polymers containing fluorine atoms contain other repeating units, it is preferable that their content be 50 mol% or less among all repeating units in the aforementioned polymers containing fluorine atoms.

[0635] (E) Polymers containing fluorine atoms can be synthesized by copolymerizing monomers protected by protecting groups as needed using known methods, followed by deprotection reactions as required. The copolymerization reaction is not particularly limited, but free radical polymerization and anionic polymerization are preferred. Japanese Patent Application Publication No. 2004-115630 can be referenced for these methods.

[0636] (E) For polymers containing fluorine atoms, a Mw of 2000~50000 is ideal, and 3000~20000 is even more ideal. If Mw is above 2000, acid will not diffuse, resolution will not deteriorate, and stability over time will not be compromised. If Mw is below 50000, solubility in solvents is sufficient, and coating defects will not occur. Furthermore, for polymers containing fluorine atoms, an Mw / Mn ratio of 1.0~2.2 is ideal, and 1.0~1.7 is even more ideal.

[0637] When the chemical amplification positive inhibitor composition of the present invention contains (E) a 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.

[0638] [(F) Other quenching agents] The chemical amplification positive inhibitor composition of the present invention may, as needed, contain a quencher other than component (A) (hereinafter also referred to as other quenchers) as component (F).

[0639] Regarding the aforementioned other quenching agents, conventional basic compounds can be cited as examples. Conventional basic compounds can include first-, second-, and third-order 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 hydroxyphenyl groups, alcoholic nitrogen-containing compounds, amides, amide imines, carbamates, etc. In particular, first-, second-, and third-order amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Application Publication No. 2008-111103, especially amine compounds with hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, sulfonate bonds, or compounds with carbamate groups described in Japanese Patent Publication No. 3790649, are more ideal. Preferred alternatives include tris(2-(methoxymethoxy)ethyl)amine, tris(2-(methoxymethoxy)ethyl)amine-N-oxide, dibutylaminobenzoic acid, α-line derivatives, and imidazole derivatives. By adding such basic compounds, the diffusion rate of acid in the resist film can be further suppressed, and the shape can be corrected.

[0640] Furthermore, regarding other quenchers mentioned above, examples include onium salts such as strontium salts, ferrophosphate salts, and ammonium salts of α-unfluorinated carboxylic acids, as described in Japanese Patent Application Publication No. 2008-158339. For α-fluorinated sulfonic acids, amide acids, or methylated acids, deprotection of the unstable acid group is necessary, but they release α-unfluorinated carboxylic acids through salt exchange with α-unfluorinated onium salts. Because α-unfluorinated carboxylic acids hardly initiate deprotection reactions, they function as quenchers.

[0641] For onium salts of carboxylic acids that are not fluorinated at the α-position, examples can be listed as represented by the following formula (F1). [Chemistry 475]

[0642] In formula (F1), R301 is a hydrogen atom or a hydrocarbon group with 1 to 40 carbon atoms containing heteroatoms, except that the hydrogen atom bonded to the α-position of the carboxyl group is replaced by a fluorine atom or a fluoroalkyl group.

[0643] R301 represents a hydrocarbon group that can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1-40 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, dibutyl, tributyl, n-pentyl, tripentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclo[5.2.1.02,6]decyl, adamantyl, and adamantylmethyl; and vinyl, allyl, propenyl, butenyl, and hexenyl. Alkenyl groups with 3 to 40 carbon atoms; cyclohexenyl and other cyclic unsaturated aliphatic hydrocarbon groups with 3 to 40 carbon atoms; 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.), dialkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); and aralkyl groups with 7 to 40 carbon atoms, such as benzyl, 1-phenylethyl, 2-phenylethyl, etc.

[0644] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Similarly, the -CH2- part of the aforementioned hydrocarbon group can be replaced by a group 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 heteroaryl groups such as thiophene; 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; and aryloxyalkyl groups such as 2-phenyl-2-sideoxyethyl, 2-(1-naphthyl)-2-sideoxyethyl, and 2-(2-naphthyl)-2-sideoxyethyl.

[0645] In formula (F1), MqA+ represents an onium cation. For the aforementioned onium cation, strontium, ferrophosphate, or ammonium cations are preferred, with strontium or ferrophosphate being more ideal. Specific examples of the aforementioned strontium cation can be those identical to those exemplified in the specific examples of the strontium cation represented by formula (Z-1) and formula (Z-3). Specific examples of the aforementioned ferrophosphate cation can be those identical to those exemplified in the specific examples of the ferrophosphate cation represented by formula (Z-2).

[0646] Regarding the anions of onium salts represented by formula (F1), examples as shown below can be listed, but are not limited to these. [Chemistry 476]

[0647] [Chemistry 477]

[0648] [Chemistry 478]

[0649] Regarding the aforementioned quenching agent, strontium salts of carboxylic acids containing iodinated benzene rings, represented by the formula (F2), can also be ideally used. [Chemistry 479]

[0650] In equation (F2), s is 1, 2, 3, 4, or 5. t is 0, 1, 2, or 3. Only 1 ≤ s + t ≤ 5. u is 1, 2, or 3.

[0651] In formula (F2), R311 is a 1-6 carbon saturated hydrocarbon group, a 1-6 carbon saturated hydrocarbon oxygen group, a 2-6 carbon saturated hydrocarbon carbonyl oxygen group, or a 1-4 carbon saturated hydrocarbon sulfonyl oxygen group, or a hydroxyl group, fluorine atom, chlorine atom, bromine atom, amino group, nitro group, cyano group, or a hydrogen atom, which may be partially or completely replaced by a halogen atom; or -N(R311A)-C(=O)-R311B or -N(R311A)-C(=O)-O-R311B. R311A is a hydrogen atom or a 1-6 carbon saturated hydrocarbon group. R311B is a 1-6 carbon saturated hydrocarbon group or a 2-8 carbon unsaturated aliphatic hydrocarbon group. When t and / or u are 2 or more, each R311 can be the same or different.

[0652] In formula (F2), L21 is a single bond or a (u+1) valent linker with 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, endamide 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.

[0653] In formula (F2), R312, R313, and R314 are each independently a halogen atom, or may contain heteroatoms and be a hydrocarbon group with 1 to 20 carbon atoms. 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, 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 groups can be replaced by hydroxyl, carboxyl, halogen, oxy, cyano, nitro, sulfonyl lactone ring, sulfonic acid group, or strontium salt-containing group. The -CH2- portion of the aforementioned hydrocarbon groups can also be replaced by ether, ester, carbonyl, amide, carbonate, or sulfonate bonds. Additionally, R312 and R313 can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

[0654] Specific examples of compounds represented by formula (F2) include those described in Japanese Patent Application Publication No. 2017-219836. Compounds represented by formula (F2) exhibit high absorption, high sensitization effect, and high acid diffusion control effect.

[0655] Regarding the aforementioned quenching agents, nitrogen-containing carboxylate compounds represented by the following formula (F3) can also be used. [Chemistry 480]

[0656] In formula (F3), R321 to R324 are each independently a hydrogen atom, -L31-CO2-, or may contain a heteroatom and a hydrocarbon group with 1 to 20 carbon atoms. R321 and R322, R322 and R323, or R323 and R324 may also bond to each other to form a ring with the carbon atoms they are bonded to. L31 is a single bond or may contain a heteroatom and a hydrocarbon group with 1 to 20 carbon atoms. R325 is a hydrogen atom or may contain a heteroatom and a hydrocarbon group with 1 to 20 carbon atoms.

[0657] In formula (F3), ring Rr is a ring with 2 to 6 carbon atoms, including carbon and nitrogen atoms in the formula. Some or all of the hydrogen atoms bonded to the carbon atoms of this ring may be replaced by hydrocarbon groups with 1 to 20 carbon atoms, or by -L31-CO2-. Some of the carbon atoms in this ring may also be replaced by sulfur, oxygen, or nitrogen atoms. The aforementioned ring can be an alicyclic or aromatic ring; ideally, it should be a 5- or 6-membered ring. Specific examples include pyridine rings, pyrrole rings, pyrrolidinium rings, piperidine rings, pyrazole rings, imidazoline rings, pyrazine rings, pyrimidine rings, pyrazine rings, imidazoline rings, pyrazolium rings, thiazole rings, thiozoline rings, thiazoline rings, triazole rings, etc.

[0658] The carboxylic acid salt represented by formula (F3) has at least one -L31-CO2- group. That is, at least one of R321 to R324 is -L31-CO2-, and / or at least one of the hydrogen atoms of the carbon atom bonded to the ring Rr is replaced by -L31-CO2-.

[0659] In formula (F3), MqB+ is a strontium cation, a monium cation, or an ammonium cation, with a strontium cation being more desirable. Regarding specific examples of the aforementioned strontium cation, examples identical to those exemplified in the specific examples of the strontium cations represented by formula (Z-1) and formula (Z-3) can be listed.

[0660] Regarding the anions of compounds represented by formula (F3), examples as shown below can be listed, but are not limited to these. [Chemistry 481]

[0661] [Chemistry 482]

[0662] [Chemistry 483]

[0663] [Chemistry 484]

[0664] [Chemistry 485]

[0665] [Chemistry 486]

[0666] Furthermore, regarding the aforementioned quenching agents, weak acid betaine-type compounds may also be used. Specific examples are listed below, but are not limited to these. [Chemistry 487]

[0667] Regarding the aforementioned quenchers, polymer-type quenchers, such as those described in Japanese Patent Application Publication No. 2008-239918, can also be cited. These quenchers enhance the rectangularity of the resist pattern by aligning to the surface of the resist film. Polymer-type quenchers also prevent film loss and rounding of the pattern top when applied to protective films for immersion exposure.

[0668] When the chemical amplification positive inhibitor composition of the present invention includes other quenchers (F), their content is preferably 0-50 parts by mass relative to 80 parts by mass of the aforementioned base polymer (B), and more preferably 0.1-40 parts by mass. The aforementioned quenchers can be used alone or in combination of two or more.

[0669] (G) Surfactants In order to improve the coatability of the substrate, the chemically amplified positive resist composition of the present invention may also contain conventional surfactants as component (G). Many of the aforementioned surfactants are well known, such as those described in International Patent Application 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 may be selected for reference.

[0670] When the chemical amplification positive inhibitor composition of the present invention includes (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.

[0671] [Resistant Pattern Formation Method] The resist patterning method of the present invention includes the following steps: forming a resist film on a substrate using the aforementioned chemically amplified positive resist composition; exposing the aforementioned resist film using high-energy rays; and developing the aforementioned patterned resist film using an alkaline developer to obtain a resist pattern.

[0672] Regarding the aforementioned substrate, substrates used for integrated circuit manufacturing (Si, SiO, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective films, etc.) or substrates used for mask circuit manufacturing (Cr, CrO, CrON, MoSi2, Si, SiO, SiO2, etc.) can be used. The aforementioned chemically amplified positive resist composition is coated onto the substrate using methods such as spin coating to achieve a film thickness of 0.03~2μm. The substrate is then pre-baked on a hot plate at a temperature of 60~150°C for 1~20 minutes, and more preferably 80~140°C for 1~10 minutes, to form a resist film.

[0673] Then, the resist film is exposed to high-energy rays to irradiate the pattern. Examples of such high-energy rays include ultraviolet light, far-ultraviolet light, excimer laser light (KrF, ArF, etc.), EB, EUV, X-rays, gamma rays, and synchrotron radiation.

[0674] When using ultraviolet light, far-ultraviolet light, excimer laser light, EUV, X-rays, gamma rays, or synchrotron radiation as the aforementioned high-energy rays, irradiation is performed using a mask to form the desired pattern, with an exposure dose ideally between 1 and 300 mJ / cm², and more ideally between 10 and 200 mJ / cm². When using EB as the high-energy ray, direct drawing is performed with an exposure dose ideally between 1 and 300 μC / cm², and more ideally between 10 and 200 μC / cm². Furthermore, the chemically amplified positive resist composition of this invention is particularly useful for EUV or EB lithography.

[0675] In addition to the usual exposure method, depending on the situation, an immersion method can also be used, in which a liquid is inserted between the mask and the resist film. In this case, a protective film that is insoluble in water can also be used.

[0676] Then, expose and bake (PEB) on a hot plate at ideal temperatures of 60-150°C for 1-20 minutes, or even more ideally at 80-140°C for 1-10 minutes.

[0677] Then, using a developer solution containing an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH) at a concentration of 0.1-5% by mass, or more ideally 2-3% by mass, development is performed for 0.1-3 minutes, or more ideally 0.5-2 minutes, by conventional methods such as dip, immersion, or spray, thereby forming the target pattern on the substrate.

[0678] The chemically amplified positive resist composition of this invention is particularly useful when used under the following conditions: high etch resistance is required, and the change in pattern linewidth and LER remain small even after prolonged exposure time up to PEB. Furthermore, because the resist composition of this invention does not easily achieve close adhesion of the resist pattern, it is particularly useful for substrates with surfaces made of materials prone to pattern peeling and pattern breakage. Examples of such substrates include those 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 this invention is particularly useful for pattern formation using a blank photomask as a substrate. [Example]

[0679] The present invention will now be specifically described with reference to synthetic examples, embodiments, and comparative examples, but the present invention is not limited to the following embodiments. Furthermore, the apparatus used is as follows. MALDI TOF-MS: S3000 manufactured by Nippon Electronics Co., Ltd.

[0680] [1] Synthesis of strontium salts [Example 1-1] Synthesis of strontium salt SQ-1 [Chemistry 488]

[0681] (1) Synthesis of intermediate In-1 Under nitrogen atmosphere, 4-iodophenol (110.0 g), potassium carbonate (82.9 g), and sodium iodide (7.5 g) were dissolved in DMF (400 g) in a reaction vessel. The temperature inside the reaction vessel was raised to 70 °C, and n-octyl bromide (106.2 g) was added dropwise. After addition, the reaction vessel was heated at 80 °C for 12 hours to mature. After maturation, the reaction solution was cooled, and water (500 g) was added to stop the reaction. The target compound was extracted with hexane (500 g). Subsequently, a conventional aqueous work-up was performed, the solvent was distilled off, and the solution was purified using a silicone column to obtain intermediate In-1 162.8 g (98% yield) as an oil.

[0682] (2) Synthesis of intermediate In-2 Under nitrogen atmosphere, intermediate In-1 (132.9 g), 2-aminobenzylthiol (55.1 g), and copper iodide (3.8 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 (48.6 g) was added dropwise. After addition, the reaction vessel was heated at 80°C for 12 hours to mature. After maturation, the reaction solution was cooled, and water (300 g) was added to stop the reaction. The target compound was extracted with toluene (500 g). After extraction, a standard aqueous work-up was performed, the solvent was distilled off, and the solution was purified using a silicone column to obtain intermediate In-2 110.7 g (84% yield) as an oil.

[0683] (3) Synthesis of intermediate In-3 Under nitrogen atmosphere, intermediate In-2 (98.9 g), triethylamine (36.4 g), and 4-dimethylaminopyridine (3.7 g) were dissolved in THF (300 g) in a reaction vessel. The temperature inside the reaction vessel was cooled to below 10°C, and methanesulfonyl chloride (37.8 g) was added dropwise. After addition, the reaction mixture was matured at 40°C for 12 hours. After maturity, the reaction solution was cooled, and water (500 g) was added to stop the reaction. The target compound was extracted with hexane (500 g). Subsequently, a conventional aqueous work-up was performed, the solvent was distilled off, and the mixture was purified using a silicone column to obtain intermediate In-3 117.4 g (96% yield) as an oil.

[0684] (4) Synthesis of intermediate In-4 Under nitrogen atmosphere, intermediate In-3 (40.8 g) and diphenylmonazine-methanesulfonate ions (41.4 g) were dissolved in anisole (150 g) in a reaction vessel. Then, copper acetate (0.9 g) was added, and the temperature in the reaction vessel was raised to 100°C and heated for 12 hours. After maturation, the reaction solution was cooled, and water (200 g) was added to stop the reaction. The target compound was extracted with dichloromethane (300 g). Following a standard aqueous work-up, the solvent was distilled off, and the mixture was purified using a silicone column to obtain intermediate In-4 50.4 g (87% yield) as an oil.

[0685] (5) Synthesis of strontium salt SQ-1 Under nitrogen atmosphere, intermediate In-4 (14.5 g) was dissolved in methanol (40 g) in a reaction vessel. A 25% (w / w) aqueous solution of sodium hydroxide (4.8 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 compound. A standard aqueous work-up was then performed to remove the solvent by distillation. The residue was then washed with diisopropyl ether to obtain 10.2 g (84% yield) of the target compound SQ-1 as an oil.

[0686] The TOF-MS results of SQ-1 are shown below. MALDI TOF-MS: POSITIVE M+484 (equivalent to C27H34NO3S2+)

[0687] [Examples 1-2~1-10] Synthesis of strontium salts SQ-2~SQ-10 Using the corresponding raw materials and known organic synthesis reactions, strontium salts SQ-2 to SQ-10 represented by the following formulas were synthesized. [Chemistry 489]

[0688] [2] Synthesis of basic polymers [Synthetic Example] Synthesis of basic polymers (P-1~P-6) The monomers were combined according to a known formulation and copolymerized in a solvent. The reaction solution was then added to hexane, and the precipitated solid was washed with hexane, isolated, and dried to obtain the basic polymers (P-1 to P-6) with the compositions shown below. The composition of the obtained basic polymers was confirmed by 1H-NMR and 13C-NMR, and Mw and Mw / Mn were confirmed by GPC (solvent: THF, standard: polystyrene). [Chemistry 490]

[0689] [3] Preparation of chemically amplified positive inhibitor composition [Examples 2-1 to 2-50, Comparative Examples 1-1 to 1-35] The components shown in Tables 1-3 below were dissolved in an organic solvent. The resulting solution was filtered through nylon filter media with a size of 5 nm and UPE filter media with a size of 1 nm, thereby preparing a chemically amplified positive type inhibitor composition. In addition, the aforementioned organic solvent is a mixture of 940 parts by mass of PGMEA, 1870 parts by mass of EL, and 1870 parts by mass of PGME.

[0690] [Table 1] inhibitor composition Basic polymers (parts by weight) Quenching agent (parts by weight) Photoacid generator (parts by weight) Polymers containing fluorine atoms (parts by weight) Example 2-1 R-1 P-1(80) SQ-1(7.0) - FP-1(1.5) Example 2-2 R-2 P-1(80) SQ-1(7.0) - - Example 2-3 R-3 P-1(80) SQ-2(7.0) - FP-1(1.5) Examples 2-4 R-4 P-1(80) SQ-3(7.0) - FP-1(1.5) Examples 2-5 R-5 P-1(80) SQ-4(7.0) - FP-1(1.5) Examples 2-6 R-6 P-1(80) SQ-5(7.0) - FP-1(1.5) Examples 2-7 R-7 P-1(80) SQ-6(7.0) - FP-1(1.5) Examples 2-8 R-8 P-1(80) SQ-7(7.0) - FP-1(1.5) Examples 2-9 R-9 P-1(80) SQ-8(7.0) - FP-1(1.5) Example 2-10 R-10 P-1(80) SQ-9(7.0) - FP-1(1.5) Example 2-11 R-11 P-1(80) SQ-10(7.0) - FP-1(1.5) Example 2-12 R-12 P-1(80) SQ-1(7.0) - FP-2(1.5) Example 2-13 R-13 P-1(80) SQ-1(7.0) - FP-3(1.5) Example 2-14 R-14 P-1(80) SQ-1(7.0) - FP-4(1.5) Example 2-15 R-15 P-1(80) SQ-1(7.0) - FP-5(1.5) Example 2-16 R-16 P-1(80) SQ-1(7.0) PAG-1(3) FP-1(1.5) Example 2-17 R-17 P-1(80) SQ-2(7.0) PAG-2(3) FP-1(1.5) Example 2-18 R-18 P-1(80) SQ-3(7.0) PAG-3(3) FP-1(1.5) Example 2-19 R-19 P-1(80) SQ-5(7.0) PAG-4(3) FP-1(1.5) Example 2-20 R-20 P-1(80) SQ-8(7.0) PAG-5(3) FP-1(1.5) Example 2-21 R-21 P-1(80) SQ-10(7.0) PAG-6(3) FP-1(1.5) Example 2-22 R-22 P-2(80) SQ-1(7.0) - FP-1(1.5) Example 2-23 R-23 P-2(80) SQ-2(7.0) - FP-1(1.5) Example 2-24 R-24 P-2(80) SQ-3(7.0) - FP-1(1.5) Example 2-25 R-25 P-2(80) SQ-4(7.0) PAG-1(3) FP-1(1.5) Example 2-26 R-26 P-2(80) SQ-5(7.0) PAG-2(3) FP-1(1.5) Example 2-27 R-27 P-2(80) SQ-6(7.0) PAG-3(3) FP-1(1.5) Example 2-28 R-28 P-2(80) SQ-9(7.0) PAG-5(3) FP-1(1.5) Example 2-29 R-29 P-2(80) SQ-1(7.0) PAG-6(3) FP-1(1.5)

[0691] [Table 2] inhibitor composition Basic polymers (parts by weight) Quenching agent (parts by weight) Photoacid generator (parts by weight) Polymers containing fluorine atoms (parts by weight) Examples 2-30 R-30 P-3(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Example 2-31 R-31 P-3(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Example 2-32 R-32 P-3(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Example 2-33 R-33 P-3(80) SQ-4(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Examples 2-34 R-34 P-3(80) SQ-5(7.0) PAG-5(8) PAG-6(4) FP-1(1.5) Example 2-35 R-35 P-3(80) SQ-9(7.0) PAG-1(12) FP-1(1.5) Examples 2-36 R-36 P-4(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Example 2-37 R-37 P-4(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Example 2-38 R-38 P-4(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Example 2-39 R-39 P-4(80) SQ-7(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Example 2-40 R-40 P-4(80) SQ-9(7.0) PAG-5(8) PAG-6(4) FP-1(1.5) Example 2-41 R-41 P-5(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Example 2-42 R-42 P-5(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Examples 2-43 R-43 P-5(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Example 2-44 R-44 P-5(80) SQ-5(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Example 2-45 R-45 P-5(80) SQ-7(7.0) PAG-5(8) PAG-6(4) FP-1(1.5) Example 2-46 R-46 P-6(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Example 2-47 R-47 P-6(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Example 2-48 R-48 P-6(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Example 2-49 R-49 P-6(80) SQ-4(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Example 2-50 R-50 P-6(80) SQ-9(7.0) PAG-5(8) PAG-6(4) FP-1(1.5)

[0692] [Table 3] inhibitor composition Basic polymers (parts by weight) Quenching agent (parts by weight) Photoacid generator (parts by weight) Polymers containing fluorine atoms (parts by weight) Comparative Example 1-1 CR-1 P-1(80) SQ-A(7.0) - FP-1(1.5) Comparative Examples 1-2 CR-2 P-1(80) SQ-A(7.0) - - Comparative Examples 1-3 CR-3 P-1(80) SQ-B(7.0) - FP-1(1.5) Comparative Examples 1-4 CR-4 P-1(80) SQ-C(7.0) - FP-1(1.5) Comparative Examples 1-5 CR-5 P-1(80) SQ-D(7.0) - FP-1(1.5) Comparative Examples 1-6 CR-6 P-1(80) SQ-A(7.0) - FP-2(1.5) Comparative Examples 1-7 CR-7 P-1(80) SQ-A(7.0) - FP-3(1.5) Comparative Examples 1-8 CR-8 P-1(80) SQ-A(7.0) - FP-4(1.5) Comparative Examples 1-9 CR-9 P-1(80) SQ-A(7.0) - FP-5(1.5) Comparative Examples 1-10 CR-10 P-1(80) SQ-A(7.0) PAG-1(3) FP-1(1.5) Comparative Examples 1-11 CR-11 P-1(80) SQ-B(7.0) PAG-2(3) FP-1(1.5) Comparative Examples 1-12 CR-12 P-1(80) SQ-C(7.0) PAG-3(3) FP-1(1.5) Comparative Examples 1-13 CR-13 P-1(80) SQ-D(7.0) PAG-4(3) FP-1(1.5) Comparative Examples 1-14 CR-14 P-1(80) SQ-A(7.0) PAG-5(3) FP-1(1.5) Comparative Examples 1-15 CR-15 P-1(80) SQ-A(7.0) PAG-6(3) FP-1(1.5) Comparative Examples 1-16 CR-16 P-2(80) SQ-A(7.0) - FP-1(1.5) Comparative Examples 1-17 CR-17 P-2(80) SQ-B(7.0) - FP-1(1.5) Comparative Examples 1-18 CR-18 P-2(80) SQ-C(7.0) - FP-1(1.5) Comparative Examples 1-19 CR-19 P-2(80) SQ-A(7.0) PAG-1(3) FP-1(1.5) Comparative Examples 1-20 CR-20 P-2(80) SQ-B(7.0) PAG-2(3) FP-1(1.5) Comparative Example 1-21 CR-21 P-2(80) SQ-D(7.0) PAG-5(3) FP-1(1.5) Comparative Examples 1-22 CR-22 P-3(80) SQ-A(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-23 CR-23 P-3(80) SQ-B(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-24 CR-24 P-3(80) SQ-C(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-25 CR-25 P-3(80) SQ-D(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-26 CR-26 P-3(80) SQ-A(7.0) PAG-1(12) FP-1(1.5) Comparative Examples 1-27 CR-27 P-4(80) SQ-A(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-28 CR-28 P-4(80) SQ-C(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-29 CR-29 P-4(80) SQ-D(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-30 CR-30 P-5(80) SQ-A(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-31 CR-31 P-5(80) SQ-B(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-32 CR-32 P-5(80) SQ-C(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-33 CR-33 P-6(80) SQ-A(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-34 CR-34 P-6(80) SQ-B(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Comparative Examples 1-35 CR-35 P-6(80) SQ-D(7.0) PAG-5(8) PAG-6(4) FP-1(1.5)

[0693] In addition, 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 in Tables 1 to 3 are as follows. [Chemistry 491]

[0694] [Chemistry 492]

[0695] [Chemistry 493]

[0696] [4] EB Microfilm Review [Examples 3-1 to 3-50, Comparative Examples 2-1 to 2-35] Each chemically amplified positive resist composition (R-1~R-50, CR-1~CR-35) was 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 create 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 points within the plane of the blank substrate, excluding the outer edge portion extending 10 mm inwards from the outer perimeter. The average film thickness and the film thickness range were calculated.

[0697] Then, exposure was performed using an electron beam exposure apparatus (EBM-5000plus manufactured by NuFlare Technology, with an accelerating voltage of 50kV), and PEB was applied at 110°C for 600 seconds. Development was then performed using a 2.38% by mass TMAH aqueous solution to obtain a positive pattern.

[0698] The obtained resist patterns were evaluated as follows. The patterned blank mask was observed using an overhead SEM (scanning electron microscope). The optimal exposure (μC / cm²) was defined as the exposure that allowed the 1:1 straight line and spacer pattern (LS) at 200 nm to be resolved at a 1:1 ratio. The smallest size among the exposures that allowed the 200 nm LS to be resolved at a 1:1 ratio was defined as the resolution (limiting resolution). The LER (Lead Resolver Ratio) of the 200 nm LS was measured using SEM. Regarding the limiting resolution of isolated spaces (IS), the smallest size among the exposures that allowed the 9:1 straight line and spacer pattern (LS) at 200 nm to be resolved at a 9:1 ratio was defined as the limiting resolution. The pattern shape was determined visually to be rectangular. The results are shown in Tables 4-6.

[0699] [Table 4] inhibitor composition Optimal exposure (µC / cm2) L / S resolution (nm) Limiting IS resolution (nm) LER (nm) Pattern Shape Example 3-1 R-1 205 28 18 2.6 rectangle Example 3-2 R-2 205 28 16 2.7 rectangle Example 3-3 R-3 200 28 18 2.8 rectangle Examples 3-4 R-4 210 30 16 2.9 rectangle Examples 3-5 R-5 200 28 18 2.7 rectangle Examples 3-6 R-6 200 30 20 2.8 rectangle Examples 3-7 R-7 205 32 16 2.9 rectangle Examples 3-8 R-8 200 28 18 2.8 rectangle Examples 3-9 R-9 205 28 16 2.9 rectangle Examples 3-10 R-10 200 30 18 2.7 rectangle Example 3-11 R-11 210 30 18 3 rectangle Example 3-12 R-12 200 30 16 2.9 rectangle Example 3-13 R-13 205 32 18 2.7 rectangle Example 3-14 R-14 200 28 18 2.8 rectangle Example 3-15 R-15 205 28 18 2.9 rectangle Example 3-16 R-16 200 30 16 2.8 rectangle Example 3-17 R-17 200 30 16 3 rectangle Example 3-18 R-18 205 30 20 2.9 rectangle Example 3-19 R-19 200 28 18 2.8 rectangle Example 3-20 R-20 205 28 18 2.7 rectangle Example 3-21 R-21 200 28 16 2.9 rectangle Example 3-22 R-22 205 30 18 2.9 rectangle Example 3-23 R-23 205 30 18 2.7 rectangle Example 3-24 R-24 205 28 16 2.9 rectangle Example 3-25 R-25 210 28 18 2.8 rectangle Example 3-26 R-26 205 32 18 2.9 rectangle Example 3-27 R-27 205 30 16 2.7 rectangle Example 3-28 R-28 200 28 16 2.9 rectangle Example 3-29 R-29 205 28 20 2.9 rectangle

[0700] [Table 5] inhibitor composition Optimal exposure (µC / cm2) L / S resolution (nm) Limiting IS resolution (nm) LER (nm) Pattern Shape Examples 3-30 R-30 205 28 18 2.9 rectangle Example 3-31 R-31 200 30 18 2.9 rectangle Example 3-32 R-32 200 30 16 3 rectangle Example 3-33 R-33 205 38 18 2.7 rectangle Examples 3-34 R-34 200 30 16 2.7 rectangle Examples 3-35 R-35 210 30 20 2.8 rectangle Examples 3-36 R-36 205 28 18 2.9 rectangle Examples 3-37 R-37 200 28 20 2.9 rectangle Examples 3-38 R-38 205 28 18 2.8 rectangle Examples 3-39 R-39 205 28 20 3 rectangle Examples 3-40 R-40 200 28 16 2.8 rectangle Examples 3-41 R-41 205 30 16 2.9 rectangle Examples 3-42 R-42 200 30 20 2.7 rectangle Examples 3-43 R-43 205 28 16 2.6 rectangle Examples 3-44 R-44 200 28 18 2.8 rectangle Examples 3-45 R-45 210 28 16 2.7 rectangle Examples 3-46 R-46 205 28 16 2.9 rectangle Examples 3-47 R-47 200 30 18 2.7 rectangle Examples 3-48 R-48 205 28 20 2.9 rectangle Examples 3-49 R-49 210 32 16 2.7 rectangle Examples 3-50 R-50 200 28 18 2.7 rectangle

[0701] [Table 6] inhibitor composition Optimal exposure (µC / cm2) L / S resolution (nm) Limiting IS resolution (nm) LER (nm) Pattern Shape Comparative Example 2-1 CR-1 200 34 twenty two 3.3 round head Comparative Example 2-2 CR-2 210 34 twenty four 3.4 Trail Comparative Examples 2-3 CR-3 200 34 twenty two 3.2 round head Comparative Examples 2-4 CR-4 205 34 twenty two 3.5 Trail Comparative Examples 2-5 CR-5 200 34 twenty two 3.4 round head Comparative Examples 2-6 CR-6 210 32 twenty four 3.3 round head Comparative Examples 2-7 CR-7 205 34 twenty two 3.3 round head Comparative Examples 2-8 CR-8 200 34 twenty four 3.4 round head Comparative Examples 2-9 CR-9 210 34 twenty two 3.6 round head Comparative Example 2-10 CR-10 205 36 twenty two 3.2 Trail Comparative Example 2-11 CR-11 200 36 twenty two 3.4 round head Comparative Example 2-12 CR-12 205 34 twenty two 3.3 Trail Comparative Example 2-13 CR-13 210 36 twenty two 3.6 round head Comparative Example 2-14 CR-14 200 32 twenty two 3.3 round head Comparative Example 2-15 CR-15 210 34 twenty four 3.6 round head Comparative Example 2-16 CR-16 200 34 twenty two 3.2 Trail Comparative Example 2-17 CR-17 205 34 twenty four 3.4 round head Comparative Example 2-18 CR-18 200 36 twenty two 3.5 round head Comparative Example 2-19 CR-19 210 34 twenty two 3.4 Trail Comparative Example 2-20 CR-20 205 34 twenty two 3.3 round head Comparative Example 2-21 CR-21 200 34 twenty four 3.6 Trail Comparative Example 2-22 CR-22 210 34 twenty two 3.4 round head Comparative Example 2-23 CR-23 200 34 twenty two 3.3 Trail Comparative Example 2-24 CR-24 200 36 twenty two 3.4 round head Comparative Example 2-25 CR-25 210 34 twenty two 3.5 round head Comparative Example 2-26 CR-26 210 32 twenty two 3.2 round head Comparative Example 2-27 CR-27 200 32 twenty two 3.3 Trail Comparative Example 2-28 CR-28 205 32 twenty two 3.2 round head Comparative Example 2-29 CR-29 200 34 twenty four 3.4 rectangle Comparative Example 2-30 CR-30 210 32 twenty two 3.3 round head Comparative Example 2-31 CR-31 205 32 twenty two 3.5 Trail Comparative Example 2-32 CR-32 200 34 twenty four 3.2 round head Comparative Example 2-33 CR-33 210 32 twenty four 3.4 round head Comparative Example 2-34 CR-34 205 34 twenty two 3.4 round head Comparative Example 2-35 CR-35 200 36 twenty four 3.3 Trail

[0702] 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 acid diffusion optimization system of the resist compositions (CR-1 to CR-35) of the comparative examples is insufficient, and deterioration in resolution, LER, and pattern rectangularity is observed.

[0703] The resist patterning method using the chemically amplified positive resist composition of the present invention is useful in semiconductor device manufacturing, especially in photolithography during the processing of transmissive and reflective blank photomasks.

Claims

1. A strontium salt, represented by the following formula (A); wherein 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; LA is a single bond, ether bond, ester bond, or sulfonate bond; Ralk is an alkyl group having 6 to 18 carbon atoms or a fluorinated alkyl group having 4 to 18 carbon atoms; when Ralk is an alkyl group having 6 to 18 carbon atoms, the alkyl group has at least one straight-chain structure having 6 or more carbon atoms; when Ralk 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; furthermore, one part of the -CH2- group of the aforementioned alkyl group and fluorinated alkyl group may also be replaced by an ether bond or a carbonyl group; Ra is an aryl group with 6 to 30 carbon atoms or an aralkyl group with 7 to 30 carbon atoms. Some or all of the hydrogen atoms of the aryl group or aralkyl group may be substituted by a group containing heteroatoms. Also, Ra and two of the two aromatic rings bonded to S+ in the formula may bond to each other and form a ring together with the sulfur atoms they bond to. Rb is a hydrocarbon group with 1 to 18 carbon atoms that may also contain heteroatoms. R1 is a halogen atom, nitro, cyano, hydroxyl, a hydrocarbon group with 1 to 20 carbon atoms that may also contain heteroatoms, an alkyloxy group with 1 to 20 carbon atoms that may also contain heteroatoms, or an alkylthio group with 1 to 20 carbon atoms that may also contain heteroatoms. When n2 is 2, 3 or 4, each R1 may be the same or different from each other. A plurality of R1 may also bond to each other and form a ring together with the carbon atoms they bond to. R2 can be a halogen atom, nitro, cyano, hydroxyl, 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 R2 can be the same or different from the others, and multiple R2s can also bond to each other and form a ring together with the carbon atoms they bond to.

2. The strontium salt of claim 1 is represented by the following formula (A1); where n1~n4, LA, Ralk, Ra, Rb, R1 and R2 are the same as those in claim 1; n5 is 0 or 1; n6 is 0, 1, 2, 3 or 4; R3 is a halogen atom, nitro, cyano, hydroxyl, or may contain a hydrocarbon group with 1 to 20 carbon atoms of heteroatoms, or a hydrocarbon oxy group with 1 to 20 carbon atoms of heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms of heteroatoms; when n6 is 2, 3 or 4, each R3 may be the same or different from each other, and multiple R3s may also bond to each other and form a ring together with the carbon atoms they bond to.

3. The strontium salt of Request 2 is represented by the following formula (A2); where n2, n4, n6, LA, Ralk, Ra, Rb, R1, R2 and R3 are the same as in Request 2.

4. A quenching agent comprising a strontium salt as claimed in claim 1.

5. A chemically amplified positive inhibitor composition comprising the quencher as claimed in claim 4.

6. The chemical amplification positive inhibitor composition as claimed in claim 5 further includes: a base polymer containing a polymer that decomposes due to the action of acid, thereby increasing its solubility in alkaline developing solutions.

7. The chemical amplification positive inhibitor composition as claimed in claim 6, wherein, The polymer contains repeating units represented by the following formula (B1); where a1 is 0 or 1; a2 is 0, 1 or 2; a3 is an integer satisfying 0 ≤ a3 ≤ 5 + 2(a2) - a4; a4 is 1, 2 or 3; RA is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; R11 is a halogen atom, a nitro group, a carboxyl group, or a 1-6 carbon saturated hydrocarbon group that may be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that may be substituted with a halogen atom; A1 is a single bond or a 1-10 carbon saturated hydrocarbon group, wherein part of the -CH2- group may also be substituted with -O-.

8. The chemical amplification positive inhibitor composition as claimed in claim 6, wherein, The polymer contains repeating units represented by the following formula (B2-1); where RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; 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; R21 is a halogen atom, or a 1-6 carbon saturated hydrocarbon group that may be substituted with a halogen atom, or a 1-6 carbon saturated hydrocarbon oxygen group that may be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl oxygen group that may be substituted with a halogen atom; A2 is a single bond or a 1-10 carbon saturated hydrocarbon group, and part of the -CH2- of the saturated hydrocarbon group may also be substituted with -O-; X is an acid-labile group when b4 is 1, and 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 chemical amplification positive inhibitor composition as claimed in claim 6, wherein, The polymer comprises repeating units represented by the following formula (B2-2); where 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; RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R22 and R23 are each independently a hydrocarbon group having 1 to 10 carbon atoms, and may also contain heteroatoms; R22 and R23 may also be bonded to each other to form a ring with the carbon atoms they are bonded to; R24 are each 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; R25 are each independently a hydrocarbon group having 1 to 10 carbon atoms, and may also contain heteroatoms. A3 represents a single bond, an enantiomer, an enantiomer, or *-C(=O)-O-A31-; A31 may also contain a hydroxyl group, an ether bond, an ester bond, or an lactone ring with 1 to 20 carbon atoms, an aliphatic enantiomer, or an enantiomer or an enantiomer; * indicates an atomic bond with a carbon atom in the main chain.

10. The chemical amplification positive inhibitor composition as claimed in claim 6, wherein, The polymer comprises at least one repeating unit selected from the repeating units represented by formula (B3), formula (B4), and formula (B5); wherein 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; RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R31 and R32 are each independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group having 1 to 6 carbons that may be substituted with a halogen atom, a saturated hydrocarbon oxygen group having 1 to 6 carbons that may be substituted with a halogen atom, or a saturated hydrocarbon carbonyl group having 2 to 8 carbons that may be substituted with a halogen atom; R33 is 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 may also be a hydroxyl group when f2 is 1 or 2; A4 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-.

11. The chemical amplification positive inhibitor composition as claimed in claim 6, wherein, The polymer comprises 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); wherein g1 and g2 are each 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; RA are each independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; Z1 is a single bond or may also have a substituent, such as an phenyl group; Z2 is a single bond, **-C(=O)-O-Z21-, **-C(=O)-NH-Z21-, or **-O-Z21-; Z21 is an aliphatic alkyl group with 1 to 6 carbon atoms, an alkyl phenyl 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; Z3 is a single bond, an ether bond, an ester bond, an amide bond, a sulfonate bond, a sulfonamide bond, a carbonate bond, or a carbamate bond; Z4 is a single bond, or an aliphatic alkyl group with 1 to 6 carbon atoms, an alkyl phenyl 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; Z5 is independently a single bond, or may contain substituents such as phenyl, naphthyl, or *-C(=O)-O-Z51-; Z51 is an aliphatic alkyl group, phenyl, or naphthyl with 1 to 10 carbon atoms, which may also contain halogen atoms, hydroxyl groups, ether bonds, ester bonds, or lactone rings; Z6 is a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Z7 is independently a single bond, ***-Z71-C(=O)-O-, ***-C(=O)-NH-Z71-, or ***-O-Z71-; Z71 may also contain heteroatoms and is an alkyl group with 1 to 20 carbon atoms; Z8 can be a single bond, ****-Z81-C(=O)-O-, ****-C(=O)-NH-Z81-, or ****-O-Z81-; Z81 can be a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms; Z9 can be a single bond, methylene, ethyl, phenyl, fluorinated phenyl, trifluoromethyl-substituted phenyl, *-C(=O)-O-Z91-, *-C(=O)-N(H)-Z91-, or *-O-Z91-; Z91 can be an aliphatic hydrocarbon group with 1 to 6 carbon atoms, phenyl, fluorinated phenyl, or trifluoromethyl-substituted phenyl, which may also contain carbonyl, ester, ether, or hydroxyl groups; * indicates an atomic bond with a carbon atom in the main chain; ** indicates an atomic bond with Z1; *** indicates an atomic bond with Z6; **** indicates an atomic bond with Z7; L1 can be a single bond, ether bond, ester bond, carbonyl group, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond; Rf1 and Rf2 can each be independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms;Rf3 and Rf4 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; Rf5 and Rf6 are each independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; however, Rf5 and Rf6 may not all be hydrogen atoms simultaneously; Rf7 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; R41 and R42 are each independently a hydrocarbon group having 1 to 20 carbon atoms, which may also contain heteroatoms; furthermore, R41 and R42 may also bond to each other and form a ring together with the sulfur atoms they are bonded to; R43 is a halogen atom other than a fluorine atom, or may also contain a hydrocarbon group having 1 to 20 carbon atoms, which may contain heteroatoms; when h3 is 2, 3, or 4, each R43 may be the same or different from each other, and multiple R43 may also bond to each other and form a ring together with the carbon atoms they are bonded to; M- is a non-nucleophilic relative ion; A+ is an onium cation.

12. The chemical amplification positive inhibitor composition as claimed in claim 6, wherein, Of all the repeating units in the base polymer, the content of repeating units with an aromatic ring skeleton is more than 60 mol%.

13. The chemical amplification positive inhibitor composition as described in claim 5 further includes an organic solvent.

14. The chemical amplification positive inhibitor composition of claim 5 further includes a photoacid generator.

15. The chemical amplification positive inhibitor composition of claim 5 further comprises: a polymer containing at least one repeating unit selected from the repeating units represented by formula (E1), formula (E2), formula (E3), and formula (E4), and may also contain at least one repeating unit selected from the repeating units represented by formula (E5) and formula (E6); wherein, 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; each of RB is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; each of RC is independently a hydrogen atom or a methyl group; R201, R202, R204, and R205 are each independently hydrogen atoms or saturated hydrocarbon groups having 1 to 10 carbon atoms; R203, R206, R207, and R208 are each independently a hydrogen atom, a hydrocarbon group with 1 to 15 carbon atoms, a fluorinated hydrocarbon group with 1 to 15 carbon atoms, or an acid-unstable group. When R203, R206, R207, and R208 are hydrocarbon groups or fluorinated hydrocarbon groups, ether bonds or carbonyl groups may also be present between carbon-carbon bonds. R209 is a hydrogen atom, or a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms containing a heteroatom may be present between carbon-carbon bonds. R210 is a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms containing a heteroatom may also be present between carbon-carbon bonds. R211 is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom. Part of the -CH2- of the saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. Z1 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; Z2 is a single bond, *-C(=O)-O- or *-C(=O)-NH-; * is an atomic bond with a carbon atom in the main chain; Z3 is a single bond, -O-, *-C(=O)-O-Z31-Z32- or *-C(=O)-NH-Z31-Z32-; Z31 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms; Z32 is a single bond, ester bond, ether bond or sulfonamide bond; * is an atomic bond with a carbon atom in the main chain.

16. The chemical amplification positive inhibitor composition of claim 5 further includes a quencher other than the quencher of claim 4.

17. A method for forming a resist pattern, comprising the following steps: forming a resist film on a substrate using a chemically amplified positive resist composition as claimed in any one of claims 5 to 16; irradiating the resist film with a high-energy ray to form a pattern; and developing the irradiated resist film with an alkaline developer.

18. The method for forming a resist pattern as described in claim 17, wherein, This high-energy ray is extreme ultraviolet light or an electron beam with a wavelength of 3-15 nm.

19. The method for forming a resist pattern as described in claim 17, wherein, The outermost surface of the substrate is made of a material containing chromium.

20. The method for forming a resist pattern as described in claim 17, wherein, The substrate is a blank photomask.