Chemically amplified positive resist composition and resist pattern forming process

Abstract

The objective of this invention is to provide a chemically amplified positive resist composition that improves the resolution during pattern formation, and enhances resist pattern fidelity, resolution, pattern accuracy, and dose tolerance, as well as a method for forming resist patterns. The solution to this objective is a chemically amplified positive resist composition comprising: (A) a quencher composed of an onium salt represented by formula (A), (B) a base polymer containing repeating units represented by formula (B1), which decomposes under acidic conditions and increases its solubility in alkaline developing solutions, and (C) a photoacid generator. In the formula, Xq- is an anion. However, the acid (XqH) with Xq- as its conjugate base has a boiling point below 165°C and a molecular weight below 150.

Description

Technical Field

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

[0002] In recent years, with the increasing integration and speed of LSI (Light Silica Electrode), the miniaturization of pattern regularity has also progressed rapidly. In the processing of patterns smaller than 0.2 μm, chemical amplification inhibitors, primarily catalyzed by acids, are used. Furthermore, regarding exposure sources, high-energy rays such as ultraviolet light, far-ultraviolet light, and electron beams (EB) are used. In particular, EB lithography, as an ultra-micro processing technique, has become indispensable in the processing of blank photomasks for semiconductor manufacturing.

[0003] Polymers containing aromatic backbones with acidic side chains, such as polyhydroxystyrene, are useful as resist compositions for KrF lithography using KrF excimer lasers. However, due to their significant absorption of light around 200 nm, they are not used as resist compositions for ArF lithography using ArF excimer lasers. Nevertheless, resist compositions for EB lithography or extreme ultraviolet (EUV) lithography, powerful techniques for forming patterns with smaller processing limits than ArF excimer lasers, have become important materials for achieving high etch resistance.

[0004] Typically, the base polymers of resist compositions for positive EB lithography and resist compositions for EUV lithography primarily use acids generated from photoacid generators by irradiation with high-energy rays as catalysts. These acids deprotect the acid-degradable protecting groups (acid-unstable groups) of the acidic functional groups of the phenolic side chains of the base polymer, making the material soluble in alkaline developing solutions.

[0005] The aforementioned acid-degrading protective groups mainly use tertiary alkyl, tertiary butoxycarbonyl, and acetal groups. While using a protective group like an acetal, which requires relatively low activation energy for deprotection, can yield a highly sensitive resist film, insufficient suppression of acid diffusion can lead to deprotection reactions even in unexposed areas of the resist film, resulting in deterioration of the line edge roughness (LER) and reduced pattern linewidth uniformity (CDU). Furthermore, especially in critical applications such as blank photomask processing, surface materials like chromium compound films (e.g., chromium oxide films deposited on the photomask substrate) can easily influence the pattern shape of the chemically amplified resist film. Maintaining a rectangular pattern outline in the resist film, regardless of the substrate type, is crucial for achieving high resolution and etched shape. Furthermore, in recent years, in order to achieve miniaturization, MBMW (Multi-Beam Mask Writing) is used for the processing of blank masks. In this case, a low-sensitivity resist composition that is beneficial to roughness (high dose region) is used. The optimization of the resist composition in this high dose region has also attracted attention.

[0006] Various improvements have been made to control sensitivity and pattern profile by adjusting the selection and combination of materials used in the inhibitor composition and processing conditions. One such improvement addresses the issue of acid diffusion. Since acid diffusion significantly impacts the sensitivity and resolution of chemically amplified inhibitor compositions, much research has been conducted on this topic.

[0007] Patent documents 1 and 2 describe examples of suppressing acid diffusion and reducing roughness by increasing the volume of benzenesulfonic acid generated from the photoacid generator due to exposure. However, the suppression of acid diffusion by the aforementioned acid generators is still insufficient, and there is a desire to develop acid generators with smaller diffusion.

[0008] Patent document 3 describes an example of controlling acid diffusion by bonding the sulfonic acid generated by exposure to the polymer used in the inhibitor composition to suppress diffusion. This method of suppressing acid diffusion by incorporating repeating units that generate acid during exposure into the base polymer is effective when obtaining patterns with small LER (Low Emission Rate). However, depending on the structure and incorporation rate of such repeating units, there are sometimes problems with the solubility of the base polymer containing the repeating units that generate acid during exposure in organic solvents.

[0009] Furthermore, when using strontium salts of acids with high acid strength, such as fluorinated alkyl sulfonic acid, as described in Patent Document 4, and polymers containing repeating units with acetal groups, there is a problem of forming patterns with large LERs. During the deprotection of acetal groups with low activation energy, the acid strength of fluorinated alkyl sulfonic acid is too high. Therefore, even if the diffusion of the acid is suppressed, a trace amount of acid will still diffuse into the unexposed areas, causing the deprotection reaction to proceed. This situation is also the case with strontium salts of benzenesulfonic acid, as described in Patent Documents 1 and 2. Therefore, it is desirable to develop an acid generator that produces an acid with a more ideal strength for the deprotection of acetal groups.

[0010] It is believed that in order to suppress acid diffusion, in addition to the aforementioned methods of increasing the volume of generated acid, there is also the method of improving the quencher (acid diffusion control agent). The quencher, which suppresses acid diffusion, is actually an essential component in order to improve the performance of the resist composition. Various quenchers have been explored to date, and generally amines and weak acid onium salts are used. Taking weak acid onium salts as an example, Patent Document 5 describes that by adding triphenylsulphurate, a good resist pattern without T-top formation, linewidth difference between isolated and dense patterns, and standing waves can be formed. Patent Document 6 describes that by adding ammonium sulfonate or ammonium carboxylate, sensitivity, resolution, and exposure latitude can be improved. Furthermore, Patent Document 7 describes a resist composition for KrF lithography and EB lithography containing a combination of photoacid generators that produce fluorine-containing carboxylic acids, which has excellent resolution and improves process tolerances such as exposure latitude and depth of focus. They are used in KrF lithography, EB lithography, or F2 lithography.

[0011] Patent document 8 describes a positive photosensitive composition for ArF lithography containing carboxylic acid onium salts. These compositions utilize the exchange between a strong acid (sulfonic acid) and a weak acid onium salt generated from a photoacid generator upon exposure, generating both a weak acid and a strong acid onium salt. This exchange replaces the highly acidic strong acid (sulfonic acid) with a weak acid (carboxylic acid), thereby inhibiting the acid decomposition reaction of unstable acid groups and reducing (controlling) the acid diffusion distance, thus functioning as a quencher.

[0012] Patent document 9 describes the use of strontium salts containing nitrogen-containing heterocyclic carboxylic acids as quenching agents, but it does not conduct a detailed discussion of low-sensitivity inhibitor compositions (high-dose region) above 50 μC.

[0013] However, when using the aforementioned inhibitor compositions containing carboxylic acid onium salts and fluorocarboxylic acid onium salts to perform patterning, the LER and resolution are still insufficient in recent years despite further miniaturization progress. Therefore, it is hoped that quenchers with lower LER and improved resolution, pattern fidelity, and dose tolerance can be developed. [Previous Technical Documents] [Patent Literature]

[0014] [Patent Document 1] Japanese Patent Application Publication No. 2009-53518 [Patent Document 2] Japanese Patent Application Publication No. 2010-100604 [Patent Document 3] Japanese Patent Application Publication No. 2011-22564 [Patent Document 4] Japanese Patent No. 5083528 [Patent Document 5] Japanese Patent No. 3955384 [Patent Document 6] Japanese Patent Application Publication No. 11-327143 [Patent Document 7] Japanese Patent No. 4231622 [Patent Document 8] Japanese Patent No. 4226803 [Patent Document 9] Japanese Patent No. 6512049 Summary of the Invention

[0015] [The problem that the invention aims to solve] The present invention is made in view of the foregoing circumstances, and aims to provide a chemically amplified positive resist composition that can obtain improved resolution during pattern formation, and improved LER, resolution, pattern fidelity and dose tolerance, as well as a method for resist pattern formation. [Methods for solving problems]

[0016] After repeated and in-depth research in order to achieve the aforementioned objectives, the inventors of this invention have obtained the following insights and thus completed the present invention: By using a chemical amplification inhibitor composition containing (A) a quencher composed of an onium salt containing a conjugated acid (XqH) with a boiling point of less than 165°C and a molecular weight of less than 150, (B) a base polymer containing a predetermined polymer, and (C) a photoacid generator, it is possible to obtain a pattern exhibiting good resolution, pattern shape, and improved LER, pattern fidelity, and dose tolerance.

[0017] That is, the present invention provides the following chemically amplified positive inhibitor composition and inhibitor pattern formation method. 1. A chemically amplified positive inhibitor composition, comprising: (A) Quenching agent, composed of onium salts represented by the following formula (A), (B) A basic polymer comprising repeating units represented by the following formula (B1), and a polymer that decomposes under the action of acid and increases its solubility in alkaline developing solutions, and (C) Photoacid generator. [Chemistry 1] In the formula, Xq- is an anion. However, the acid (XqH) with Xq- as its conjugate base has a boiling point below 165℃ and a molecular weight below 150. Z+ represents strontium cation as shown in formula (Z-1), monium cation as shown in formula (Z-2), ammonium cation as shown in formula (Z-3), or strontium cation as shown in formula (Z-4). [Chemistry 2] In the formula, R1 to R9 are halogen atoms or hydrocarbon groups with 1 to 30 carbon atoms that may contain heteroatoms. Also, any two of R1 to R3 may bond to each other and form a ring together with the sulfur atoms they are bonded to, and any two of R6 to R9 may bond to each other and form a ring together with the nitrogen atoms they are bonded to. [Chemistry 3] In the formula, m1 is 0 or 1. m2 is 0 or 1. m3 is 0 or 1. m4 is 0, 1, 2, 3, or 4. m5 is 0, 1, 2, 3, or 4. m6 is 0, 1, 2, 3, 4, 5, or 6. m7 is 0, 1, 2, 3, 4, 5, or 6. m8 is 0, 1, or 2. m9 is 0, 1, or 2. m10 is 0, 1, or 2. m11 is 0 or 1. m12 is 0, 1, 2, 3, or 4. m13 is 0, 1, or 2. m14 is 0, 1, or 2. 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. RF1 to RF3 are independently fluorine atoms, fluorinated saturated hydrocarbon groups with 1 to 6 carbon atoms, fluorinated saturated hydrocarbon group oxygen with 1 to 6 carbon atoms, or fluorinated saturated hydrocarbon group thio group with 1 to 6 carbon atoms. When m5 is 2 or more, each RF1 can be the same or different from the others; when m6 is 2 or more, each RF2 can be the same or different from the others; when m7 is 2 or more, each RF3 can be the same or different from the others. R10~R13 can be halogen atoms other than iodine and fluorine atoms, nitro, cyano, or may contain hydrocarbon groups with 1~20 carbon atoms, hydrocarbon oxygen groups with 1~20 carbon atoms, or hydrocarbon thio groups with 1~20 carbon atoms. When m8 is 2, the two R10s can be the same or different, and the two R10s can also bond to each other and form a ring with the carbon atoms they are bonded to. When m9 is 2, the two R11s can be the same or different, and the two R11s can also bond to each other and form a ring with the carbon atoms they are bonded to. When m10 is 2, the two R12s can be the same or different, and the two R12s can also bond to each other and form a ring with the carbon atoms they are bonded to. When m13 is 2, the two R13s can be the same or different, and the two R13s can also bond to each other and form a ring with the carbon atoms they are bonded to. Furthermore, the aromatic rings of S+ directly bonded to the strontium cation can also bond to each other and form rings together with S+. LA and LB are independently single bonds, ether bonds, ester bonds, amide bonds, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds, respectively. XL is a single bond, or may contain a heteroatom of 1 to 40 carbon atoms in an alkyl group. [Chemistry 4] In the formula, a1 is 0 or 1. a2 is 0, 1 or 2. a3 is an integer that satisfies 0 ≤ a3 ≤ 5 + 2(a2) - a4. a4 is 1, 2 or 3. RA can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R21 can be a halogen atom, a nitro group, a carboxyl group, or a 1-6 carbon saturated hydrocarbon group that can be substituted by a halogen atom, or a 1-6 carbon saturated hydrocarbon oxygen group that can be substituted by a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl oxygen group that can be substituted by 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 replaced by -O-. 2. As in 1., the chemical amplification positive inhibitor composition, wherein the conjugate acid XqH of the anion Xq- is formic acid, acetic acid, propionic acid, butyric acid, trifluoroacetic acid, 3,3,3-trifluoropropionic acid, trimethylacetic acid, or nitric acid. 3. A chemically amplified positive inhibitor composition as described in 1. or 2, wherein the aforementioned polymer further contains a repeating unit represented by the following formula (B2-1). [Chemistry 5] In the formula, 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. R31 is a halogen atom, or a 1-6 carbon saturated hydrocarbon group that can be replaced by a halogen atom, or a 1-6 carbon saturated hydrocarbon oxygen group that can be replaced by a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl oxygen group that can be replaced by a halogen atom. A2 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-. When b4 is 1, X is an acid-labile group; when b4 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. 4. A chemically amplified positive inhibitor composition as described in any of 1. to 3, wherein the aforementioned polymer further contains 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. R32 and R33 are each an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. R32 and R33 can also bond to each other and form a ring together with the carbon atoms they are bonded to. R34 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. R35 can be independently a 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 be an aliphatic enantiomer with 1 to 20 carbon atoms, containing a hydroxyl group, an ether bond, an ester bond, or an lactone ring, or an enantiomer or an enantiomer. * indicates an atomic bond with a carbon atom in the main chain. 5. A chemical amplification positive inhibitor composition as described in any one of 1 to 4, wherein the aforementioned polymer contains at least one repeating unit selected from the repeating unit represented by formula (B3), the repeating unit represented by formula (B4), and the repeating unit represented by formula (B5). [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. R41 and R42 are, independently, a hydroxyl group, a halogen atom, a 1-6 carbon saturated hydrocarbon group that can be substituted by a halogen atom, a 1-6 carbon saturated hydrocarbon oxygen group that can be substituted by a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl oxygen group that can be substituted by a halogen atom. R43 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 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. 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-. 6. A chemical amplification positive inhibitor composition as described in any one of 1. to 5, wherein the aforementioned polymer contains at least one repeating unit selected from the following formula (B6), the following formula (B7), the following formula (B8), the following formula (B9), and the following formula (B10). [Chemistry 8] In the formula, g1 and g2 are independently 0, 1, 2 or 3. h1 is 0 or 1. h2 is 0, 1, 2, 3 or 4. h3 is 0, 1, 2, 3 or 4. However, when h1 is 0, 0 ≤ h2 + h3 ≤ 4, and when h1 is 1, 0 ≤ h2 + h3 ≤ 6. RA can be independently represented by a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z1 is a single bond or may have substituents such as phenyl groups. 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 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 alkyl phenyl group, or a divalent group obtained by combining them, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups. Z5 can be a single bond, or it can have 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, and the aliphatic alkyl group 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 and may contain 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 independently hydrogen atoms, fluorine atoms, or fluorinated saturated hydrocarbon groups with 1 to 6 carbon atoms, respectively. Rf5 and Rf6 are independently hydrogen atoms, fluorine atoms, or fluorinated saturated hydrocarbon groups with 1 to 6 carbon atoms, respectively. However, not all Rf5 and Rf6 are simultaneously hydrogen atoms. 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. R51 and R52 are each independently a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. Furthermore, R51 and R52 can also bond to each other and form a ring together with the sulfur atoms they are bonded to. R53 can be a halogen atom other than fluorine, or it can also be a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms. When h3 is 2, 3 or 4, multiple R53s can 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. 7. A chemical amplification positive inhibitor composition as described in any one of 1. to 6, wherein the content of repeating units having an aromatic ring skeleton in all repeating units of the aforementioned base polymer is 60 mol% or more. 8. Any of the chemical amplification positive inhibitor compositions in 1 to 7, further contains (D) an organic solvent. 9. The chemical amplification positive inhibitor composition of any one of 1. to 8. further contains (E) a polymer containing fluorine atoms, which contains 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 further 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. RB can be independently represented by a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. RC can be independently represented by a hydrogen atom or a methyl group. R101, R102, R104 and R105 are each independently a hydrogen atom or a saturated hydrocarbon group with 1 to 10 carbon atoms. R103, R106, R107, and R108 are, independently, hydrogen atoms, hydrocarbon groups with 1 to 15 carbon atoms, fluorinated hydrocarbon groups with 1 to 15 carbon atoms, or acid-unstable groups. When R103, R106, R107, and R108 are hydrocarbon groups or fluorinated hydrocarbon groups, ether bonds or carbonyl groups can also be inserted between carbon-carbon bonds. R109 is a hydrogen atom, or it may be a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms with a heteroatom inserted between carbon-carbon bonds. R110 can also be a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which a heteroatom-containing group is inserted between carbon-carbon bonds. R111 is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, and part of the -CH2- of the aforementioned saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. X1 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. X2 represents a single bond, *-C(=O)-O-, or *-C(=O)-NH-. * represents an atomic bond with a carbon atom in the main chain. X3 is a single bond, -O-, *-C(=O)-O-X31-X32-, or *-C(=O)-NH-X31-X32-. X31 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms. X32 is a single bond, ester bond, ether bond, or sulfonamide bond. * represents an atomic bond with a carbon atom in the main chain. 10. Any chemical amplification positive inhibitor composition as described in any of 1. to 9. further contains a quencher other than the quencher described in 1. 11. A method for forming a resist pattern, comprising the following steps: A resist film is formed on a substrate using a chemically amplified positive resist composition as described in any of 1. to 10. The pattern was created by irradiating the aforementioned resist film with high-energy rays, and The resist film with the previously irradiated pattern was developed using an alkaline developer. 12. The resist pattern forming method as described in 11, wherein the aforementioned high-energy rays are EUV or EB with a wavelength of 3 to 15 nm. 13. The resist pattern forming method of 11 or 12, wherein the outermost surface of the aforementioned substrate is composed of a chromium-containing material. 14. The resist pattern forming method of any one of 11. to 13, wherein the aforementioned substrate is a blank photomask. [Effects of the Invention]

[0018] The chemically amplified positive resist composition of this invention utilizes the effect of the onium salt represented by formula (A) to effectively control acid diffusion caused by exposure during pattern formation. When using this composition to form a resist film and create a pattern, patterns with extremely high resolution, high pattern fidelity, and improved LER and dose tolerance can be obtained. Furthermore, the repeating unit represented by formula (B1) exhibits good solubility in alkaline developer and also improves the adhesion of the resist film to the substrate during formation.

[0019] The resist patterning method using the chemically amplified positive resist composition of the present invention can form patterns with high resolution, pattern fidelity, and improved LER and dose tolerance, thus making it ideal for use in microfabrication technology, especially in EUV lithography and EB lithography. Implementation

[0020] The present invention will now be described in detail. Furthermore, in the following description, asymmetric carbon may be present depending on the structure represented by the chemical formula, and sometimes mirror-image isomers and non-mirror-image isomers may exist; in these cases, a general formula is used to represent these isomers. These isomers may be used individually or in mixtures.

[0021] [Chemical Amplification Positive Inhibitor Composition] The chemical amplification positive inhibitor composition of the present invention is characterized by containing: (A) a quencher composed of an onium salt containing an anion with a boiling point of less than 165°C and a molecular weight of less than 150 containing a conjugate acid (XqH); (B) a base polymer containing a predetermined polymer that decomposes due to the action of acid and increases the solubility in alkaline developing solution; and (C) a photoacid generator.

[0022] [(A) Quenching agent] The onium salt system used as a quenching agent in component (A) is represented by the following formula (A). [Chemistry 10]

[0023] In formula (A), Xq- is an anion. However, the acid (XqH) with Xq- as its conjugate base must have a boiling point below 165℃ and a molecular weight below 150. Examples of XqH include: formic acid, acetic acid, propionic acid, butyric acid, trifluoroacetic acid, 3,3,3-trifluoropropionic acid, trimethylacetic acid, nitric acid, etc. XqH should preferably have a boiling point below 150℃ and a molecular weight below 120.

[0024] In formula (A), Z+ is an onium cation. The aforementioned onium cation is preferably a strontium cation represented by formula (Z-1), a monium cation represented by formula (Z-2), or an ammonium cation represented by formula (Z-3). [Chemistry 11]

[0025] In formulas (Z-1) to (Z-3), R1 to R9 are halogen atoms or hydrocarbon groups with 1 to 30 carbon atoms that may contain heteroatoms.

[0026] Halogen atoms represented by R1~R9 can be listed as: fluorine atom, chlorine atom, bromine atom, iodine atom, etc.

[0027] R1 to R9 represent hydrocarbon groups that 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, secondary butyl, and tertiary butyl; cyclic saturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 30 carbon atoms such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclohexenyl; aryl groups with 6 to 30 carbon atoms such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 30 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them, but preferably aryl. 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, and a portion of the -CH2- group of the hydrocarbon group can also 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, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0028] Furthermore, R1 and R2 can also bond to each other and form a ring together with the sulfur atoms they are bonded to. In this case, the strontium cation represented by formula (Z-1) can be represented by the following formulas, etc. [Chemistry 12] In the formula, the dashed lines represent the atomic bonds between R and R3.

[0029] In addition, any two of R6 to R9 can bond to each other and form a ring together with the nitrogen atoms they are bonded to.

[0030] Specific examples of strontium cations represented by formula (Z-1) 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 thereto. Specific examples of monium cations represented by formula (Z-2) include those described in paragraph

[0181] of Japanese Patent Application Publication No. 2024-000259, but are not limited thereto. Ammonium cations represented by formula (Z-3) include those described in paragraph

[0221] of Japanese Patent Application Publication No. 2024-000259, but are not limited thereto.

[0031] The aforementioned onium cation should also be a strontium cation represented by the following formula (Z-4). [Chemistry 13]

[0032] In formula (Z-4), m1 is 0 or 1. When m1 is 0, it is a benzene ring; when m1 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have m1 = 0 for the benzene ring. m2 is 0 or 1. When m2 is 0, it is a benzene ring; when m2 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have m2 = 0 for the benzene ring. m3 is 0 or 1. When m3 is 0, it is a benzene ring; when m3 is 1, it is a naphthalene ring. Considering solvent solubility, it is preferable to have m3 = 0 for the benzene ring.

[0033] In formula (Z-4), m4 is 0, 1, 2, 3, or 4. The more iodine atoms in the cation structure, the higher the absorption of EUV, but there is a concern that it will become less solvent-soluble and precipitate in the inhibitor composition. Therefore, m4 should preferably be 0, 1, 2, or 3, with 0, 1, or 2 being more preferred.

[0034] In formula (Z-4), m5 can be 0, 1, 2, 3, or 4. Considering the availability of raw materials, m5 should preferably be 0, 1, 2, or 3, with 0, 1, or 2 being more preferred. m6 can be 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, m6 should preferably be 0, 1, 2, or 3, with 0, 1, or 2 being more preferred. m7 can be 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, m7 should preferably be 0, 1, 2, or 3, with 0, 1, or 2 being more preferred.

[0035] In formula (Z-4), m8 is 0, 1, or 2. Considering the availability of raw materials, m8 should ideally be 0 or 1. m9 is 0, 1, or 2. Considering the availability of raw materials, m9 should ideally be 0 or 1. m10 is 0, 1, or 2. Considering the availability of raw materials, m10 should ideally be 0 or 1.

[0036] In formula (Z-4), 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, it is preferable to have a benzene ring with m11 of 0.

[0037] In formula (Z-4), m12 is 0, 1, 2, 3 or 4. The more iodine atoms in the cation structure, the higher the absorption of EUV, but there is a concern that it will become less solvent-soluble and precipitate in the inhibitor composition. Therefore, m12 should preferably be 0, 1, 2 or 3, with 0, 1 or 2 being better.

[0038] In equation (Z-4), m13 is 0, 1, or 2. From the perspective of raw material acquisition, m13 should preferably be 0 or 1. m14 is 0, 1, or 2. From the perspective of synthesis, m14 should preferably be 0 or 1.

[0039] 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.

[0040] In formula (Z-4), RF1 to RF3 are independently fluorine atoms, fluorinated saturated hydrocarbon groups with 1 to 6 carbon atoms, fluorinated saturated hydrocarbon oxygen groups with 1 to 6 carbon atoms, or fluorinated saturated hydrocarbon thio groups with 1 to 6 carbon atoms. Among them, trifluoromethyl, trifluoromethoxy, and trifluorothiomethoxy are preferred. 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.

[0041] In formula (Z-4), R10 to R13 are halogen atoms other than iodine and fluorine atoms, nitro, cyano, or may contain a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, a hydrocarbon oxygen group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. The hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon thio group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples can be given similarly to those illustrated in the description of formula (Z-1) where the hydrocarbon groups are represented by R1 to R9. Furthermore, some or all of the hydrogen atoms in the hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon sulfur group can be replaced by a group containing heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, and halogen atom. Also, a portion of the -CH2- group can be replaced by a group containing heteroatoms such as oxygen atom, sulfur atom, and nitrogen atom. As a result, the hydrocarbon group 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.

[0042] Furthermore, when m8 is 2, the two R10 atoms can be the same or different, and they can also bond to each other and form a ring together with the carbon atoms they are bonded to. When m9 is 2, the two R11 atoms can be the same or different, and they can also bond to each other and form a ring together with the carbon atoms they are bonded to. When m10 is 2, the two R12 atoms can be the same or different, and they can also bond to each other and form a ring together with the carbon atoms they are bonded to. When m13 is 2, the two R13 atoms can be the same or different, and they can also bond to each other and form a ring together 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, adamantane rings, etc. 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, and some of the -CH2- in the aforementioned ring can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0043] Furthermore, the aromatic rings of S+ in the strontium cation represented by formula (Z-4) 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 in the following formulas, etc. [Chemistry 14] In the formula, the dashed lines represent atomic bonds.

[0044] In formula (Z-4), LA and LB are independently single bonds, ether bonds, ester bonds, amide bonds, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Among them, LA is preferably a single bond, ether bond, ester bond, or sulfonate bond, with ester bonds or sulfonate bonds being more preferred. LB is preferably a single bond, ether bond, or ester bond, with single bonds being more preferred.

[0045] In formula (Z-4), XL is a single bond, or may contain a heteroatom with 1 to 40 carbon atoms in an extended hydrocarbon group. The aforementioned extended hydrocarbon group can be linear, branched, or cyclic; specific examples include alkyl dienes and cyclic saturated extended hydrocarbon groups. Specific examples of the aforementioned heteroatoms include oxygen atoms, nitrogen atoms, and sulfur atoms.

[0046] XL can also contain heteroatoms with carbon atoms of 1 to 40, and specific examples are shown below, but are not limited to these. Additionally, in the following formula, * indicates atomic bonds with LA and LB, respectively. [Chemistry 15]

[0047] [Chemistry 16]

[0048] [Chemistry 17]

[0049] [Chemistry 18]

[0050] Among them, XL-0~XL-22 and XL-47~XL-58 are preferred.

[0051] The strontium cation represented by formula (Z-4) should preferably be represented by the following formula (Z-4-1). [Chemistry 19] In the formula, m4~m10, m12~m14, RF1~RF3, R10~R13, LA, LB and XL are the same as those mentioned above.

[0052] The cation represented by formula (Z-4-1) should preferably be represented by formula (Z-4-2). [Chemistry 20] In the formula, m4~m10, RF1~RF3 and R10~R12 are the same as those mentioned above.

[0053] Specific examples of strontium cations represented by formula (Z-4) are shown below, but are not limited thereto. Additionally, in the following formula, Me is a methyl group. [Chemistry 21]

[0054] [Chemistry 22]

[0055] [Chemistry 23]

[0056] [Chemistry 24]

[0057] [Chemistry 25]

[0058] [Chemistry 26]

[0059] [Chemistry 27]

[0060] [Chemistry 28]

[0061] [Chemistry 29]

[0062] [Chemistry 30]

[0063] [Chemistry 31]

[0064] [Chemistry 32]

[0065] [Chemistry 33]

[0066] [Chemistry 34]

[0067] [Chemistry 35]

[0068] [Chemistry 36]

[0069] [Chemistry 37]

[0070] [Chemistry 38]

[0071] [Chemistry 39]

[0072] [Chemistry 40]

[0073] [Chemistry 41]

[0074] [Chemistry 42]

[0075] [Chemistry 43]

[0076] [Chemistry 44]

[0077] [Chemistry 45]

[0078] [Chemistry 46]

[0079] [Chemistry 47]

[0080] [Chemistry 48]

[0081] Specific examples of the aforementioned onium salts can be any combination of the aforementioned anions and cations.

[0082] The aforementioned onium salts can be synthesized, for example, using the same method as that described in Japanese Patent Application Publication No. 2020-91312, but are not limited thereto.

[0083] The aforementioned gallium salts can be ideally used as quenching agents. In addition, in the present invention, a quencher refers to a material that resorts to capturing a strong acid that produces a self-photoacid-generating agent to prevent its diffusion towards the unexposed portion and is used to form a desired pattern. Photoacid generators are compounds that produce strong acids due to irradiation with high-energy rays, and strong acids are compounds having an acidity sufficient to cause a deprotection reaction of an acid labile group. Acids such as acetic acid, nitric acid, and trifluoroacetic acid produced by the gillium salt of the present invention are not sufficiently acidic to cause a deprotection reaction when the acid labile group is a class 3 ester or a class 3 ether. In addition, photoacid generating agents that produce sulfonic acid, amido, or methylated acids fluorinated at the α site may be of the additive type or of the polymer bonding type bonded to the base polymer.

[0084] If ilium salts that will produce acids such as acetic acid, nitric acid, trifluoroacetic acid, and photoacid-generating agents that will produce sulfonic acids will produce strong acids are illuminated in a mixed state, acetic acid, nitric acid, trifluoroacetic acid and other acids and sulfonic acids will be produced. The photoacid generator does not completely decompose, so there will be undecomposed photoacid generator nearby. Here, if gallium salts and sulfonic acids that produce acids such as acetic acid, nitric acid, and trifluoroacetic acid coexist, initially the sulfonic acid will undergo ion exchange with the gillium salts that produce carboxylic acid and nitric acid. This is due to the more stable sulfonate salts of high strength as acids. On the other hand, even the presence of sulfonium salts and acids such as acetic acid, nitric acid, and trifluoroacetic acid do not cause ion exchange.

[0085] Structural features of the gillium salts of the present invention include anions having a boiling point of less than 165°C and a molecular weight of less than 150 with a conjugated acid (XqH). It is presumed that the boiling point of the weak acid produced from the gillium salts of the present invention is low, so that a portion of the acid produced will volatilize. The weak acid produced migrates to the developer and causes swelling of the resistor film, which results in pattern collapse. On the contrary, as in the aforementioned gallium salts, weak acids can reduce swelling if volatilized. that is, the limit resolution can be improved. Also, the molecular weight of the aforementioned anions is small, so it is easy to flow due to the developer. Therefore, trace amounts of dissolved residue are not easily left at the interface of the exposed and unexposed parts after development, which will improve the LWR as a result. The aforementioned gallium salt-type quencher has low acid diffusion as previously described since the acid produced is a weak acid that is not a sulfonic acid. The acid-generating agent can be more ideally controlled if the acid-generating agent is made into a polymer bonding type incorporating the photoacid-generating unit into the base polymer used.

[0086] In the chemically amplified positive resist composition of this invention, the content of (A) quencher relative to 80 parts by mass of the base polymer described later is preferably 0.1 to 40 parts by mass, and more preferably 0.5 to 30 parts by mass. If the content of (A) quencher is within the aforementioned range, the sensitivity and resolution are good, and there is no concern about foreign matter being generated in the resist film after development or during peeling, which is therefore more ideal. (A) Quencher can be used alone or in combination of two or more.

[0087] [(B) Basic Polymer] (B) The base polymer of the component contains a repeating unit represented by the following formula (B1) (hereinafter also referred to as repeating unit B1), and is a polymer that decomposes due to the action of acid and increases its solubility in alkaline developing solution. [Chemistry 49]

[0088] In formula (B1), a1 is 0 or 1. a2 is 0, 1, or 2; when it is 0, it represents the benzene skeleton; when it is 1, it represents the naphthalene skeleton; and when it 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, it is preferable that a3 is 0, 1, 2, or 3, and a4 is 1, 2, or 3. When a2 is 1 or 2, it is preferable that a3 is 0, 1, 2, 3, or 4, and a4 is 1, 2, or 3.

[0089] In formula (B1), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0090] In formula (B1), R21 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 by a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that can be substituted by a halogen atom. The saturated hydrocarbon group, as well as the saturated hydrocarbon oxygen group and the saturated hydrocarbon carbonyl oxygen group, can be any of the following: linear, branched, or cyclic. Specific examples include: alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; and groups obtained by combining them. If the number of carbon atoms is below the upper limit, the solubility in alkaline developing solutions is good. When a3 is 2 or more, each R21 can be the same or different.

[0091] 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 may be replaced by -O-. The aforementioned saturated alkyl group can be any of the following: linear, branched, or cyclic. Specific examples include: methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers, etc., alkyl diyl groups with 1 to 10 carbon atoms; cyclopropane diyl, cyclobutane diyl, cyclopentane diyl, cyclohexane diyl, etc., cyclic saturated alkyl groups with 3 to 10 carbon atoms; and groups obtained by combining them. When the aforementioned saturated alkyl group contains an ether bond, if a1 in formula (B1) is 1, it can also be inserted at any position other than between the α- and β-carbon atoms relative to the ester oxygen atom. Furthermore, when a1 is 0, the atom bonded to the main chain becomes an ether oxygen atom, and a second ether bond can be inserted at any position other than between the α-position carbon atom and the β-position carbon atom 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 more ideal.

[0092] When a1 is 0 and A1 is a single bond, that is, when the aromatic ring is directly bonded to the polymer backbone (i.e., it does not have a linker group (-C(=O)-O-A1-)), ideal examples of repeating unit B1 can be listed from units such as 3-hydroxystyrene, 4-hydroxystyrene, 5-hydroxy-2-vinylnaphthalene, and 6-hydroxy-2-vinylnaphthalene. Specifically, examples can be listed below, but are not limited thereto. In addition, RA in the following formula is the same as described above. [Transformation 50]

[0093] [Chemistry 51]

[0094] [Chemistry 52]

[0095] When a1 is 1 (i.e., has -C(=O)-O-A1- as a linking basis), ideal examples of repeating unit B1 can be listed as follows, but are not limited to these. In addition, RA is the same as above in the following formula. [Chemistry 53]

[0096] [Chemistry 54]

[0097] [Chemistry 55]

[0098] [Chemistry 56]

[0099] [Chemistry 57]

[0100] The content of repeating unit B1 in all repeating units constituting the aforementioned polymer is preferably 15-90 mol%, and more preferably 15-80 mol%. However, it is ideal to include at least one of the repeating units represented by formula (B3) and formula (B4) that impart higher etch resistance to the polymer described below, and that the unit has a phenolic hydroxyl group as a substituent, and the ratio falls within the aforementioned range. Repeating unit B1 may be used alone or in combination of two or more.

[0101] In order to make a positive resist composition, the aforementioned polymer should contain repeating units with acidic functional groups protected by acid-instable groups, that is, repeating units that are protected by acid-instable groups and become alkali-soluble due to the action of acid (hereinafter also referred to as repeating unit B2).

[0102] The best example of repeating unit B2 can be listed as follows: (B2-1) (hereinafter also called repeating unit B2-1). [Chem.58]

[0103] In formula (B2-1), b1 is 0 or 1. b2 is 0, 1, or 2; when b2 is 0, it represents the benzene skeleton; when b2 is 1, it represents naphthalene; and when b2 is 2, it represents 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, b3 should ideally be 0, 1, 2, or 3, and b4 should ideally be 1, 2, or 3. When b2 is 1 or 2, b3 should ideally be 0, 1, 2, 3, or 4, and b4 should ideally be 1, 2, or 3.

[0104] In formula (B2-1), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0105] In formula (B2-1), R31 is a halogen atom, a 2-8 carbonyl carbonyl group that can be substituted with a halogen atom, a 1-6 carbonyl group that can be substituted with a halogen atom, or a 1-6 carbonyl carbonyl group that can be substituted with a halogen atom. The aforementioned saturated hydrocarbon group, as well as the saturated hydrocarbon carbonyl group and the saturated hydrocarbon 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 R31 can be the same or different.

[0106] In formula (B2-1), A2 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 may also be replaced by -O-. The aforementioned saturated alkyl group can be any of the following: linear, branched, or cyclic. Specific examples include: methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers, etc., alkyl diyl groups with 1 to 10 carbon atoms; cyclopropane diyl, cyclobutane diyl, cyclopentane diyl, cyclohexane diyl, etc., cyclic saturated alkyl groups with 3 to 10 carbon atoms; and groups obtained by combining them. When the aforementioned saturated alkyl group contains an ether bond, if b1 in formula (B2-1) is 1, it can also be inserted at any position other than between the α- and β-carbon atoms relative to the ester oxygen atom. Furthermore, when b1 is 0, the atom bonded to the main chain becomes an ether oxygen atom, and a second ether bond can be inserted at any position other than between the α- and β-position carbon atoms 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.

[0107] In formula (B2-1), when b4 is 1, X is an acid-labile group. When b4 is 2 or 3, X is either a hydrogen atom or an acid-labile group independently, but at least one is an acid-labile group. That is, the repeating unit B2-1 is either a phenolic hydroxyl group bonded to an aromatic ring that is protected by an acid-labile group, or a carboxyl group bonded to an aromatic ring that is protected by an acid-labile group. The aforementioned acid-labile group is not particularly limited to those known to be used in many chemically amplified positive inhibitor compositions that are deactivated by acid to provide an acidic group; any of these can be used.

[0108] Examples of the aforementioned acid-labile groups include tertiary saturated hydrocarbon groups. To obtain the monomers for polymerization by distillation, the aforementioned tertiary saturated hydrocarbon groups should preferably have 4 to 18 carbon atoms.

[0109] The saturated hydrocarbon groups bonded to the aforementioned tertiary carbon atoms should preferably have 1 to 15 carbon atoms. These saturated hydrocarbon groups with 1 to 15 carbon atoms can be linear, branched, or cyclic, and their carbon-carbon bonds may also contain functional groups containing oxygen atoms, such as ether bonds or carbonyl groups. Furthermore, the saturated hydrocarbon groups bonded to the tertiary carbon atoms can also bond to each other and form rings together with the tertiary carbon atoms they are bonded to.

[0110] Examples of the aforementioned alkyl substituents 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.

[0111] The aforementioned tertiary saturated hydrocarbon groups can be listed as follows: tertiary butyl, tertiary pentyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1,2-trimethylpropyl, 1-adamantyl-1-methylethyl, 1-methyl-1-(2-norbornenyl)ethyl, 1-methyl-1-(tetrahydrofuran-2-yl)ethyl, 1-methyl-1-(7-oxanorbornen-2-yl)ethyl, 1-methylcyclopentyl, 1-ethylcyclopentyl, 1-propylcyclopentyl, 1-cyclopentylcyclopentyl, 1-cyclohexylcyclopentyl, 1-(2-tetrahydrofuranyl)cyclopentyl, 1-(7-oxanorbornen-2-yl)cyclopentyl, 1-methylcyclohexyl, 1-ethylcyclohexyl, 1-cyclopentylcyclohexyl, 1-cyclohexylcyclohexyl 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.

[0112] Furthermore, the aforementioned acid-indestructible groups can be exemplified by groups represented by formula (B2-1-1). Groups represented by formula (B2-1-1) are commonly used as acid-indestructible groups, and are a useful option as acid-indestructible groups that can stably provide a more rectangular pattern at the interface between the pattern and the substrate. When X is a group represented by formula (B2-1-1), an acetal structure is formed. [Chemistry 59] In the formula, the dashed lines represent atomic bonds.

[0113] 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 any of the following: straight-chain, branched, or cyclic.

[0114] RL1 is appropriately selected based on the design considerations regarding the sensitivity of the decomposable group to acids. For example, in a design where strong acid decomposition is required after ensuring high stability, a group with a hydrogen atom or a carbon atom bonded to the acetal carbon as a tertiary carbon atom is preferable. Examples of RL1 groups with tertiary carbon atoms bonded to the acetal carbon include tertiary butyl, tertiary pentyl, and 1-adamantyl, but are not limited to these. In a design that utilizes high reactivity with high sensitivity to pH changes, a straight-chain alkyl group is preferable. Although it also depends on the combination of acid generators and quenchers incorporated into the inhibitor composition, for the design of RL2, when a larger alkyl group is chosen at the end and the solubility change due to decomposition is large, RL1 should ideally have a secondary carbon atom bonded to the acetal carbon. Examples of RL1 groups with secondary carbon atoms bonded to the acetal carbon include isopropyl, secondary butyl, cyclopentyl, and cyclohexyl, but are not limited to these.

[0115] 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. A portion of the -CH2- group is replaced by heteroatoms such as oxygen or sulfur atoms, resulting in the presence of ether bonds or thioether bonds. Specific examples of the aforementioned hydrocarbon group include saturated hydrocarbon groups with 1 to 30 carbon atoms and aryl groups with 6 to 30 carbon atoms. Especially in the formation of fine patterns, to obtain higher resolution, RL2 should preferably be a hydrocarbon group with 1 to 6 carbon atoms. When RL2 is a hydrocarbon group with 1 to 6 carbon atoms, the alcohol generated after the deprotection reaction using acid is water-soluble. Therefore, when forming positive patterns using an alkaline developer, it will dissolve in the developer, thus suppressing residual defects in the exposed area.

[0116] Ideal examples of the basis represented by equation (B2-1-1) can be listed below, but are not limited to these. Furthermore, in the following equation, RL1 is the same as above, and dashed lines represent atomic bonds. [Transformation 60]

[0117] [Chemistry 61]

[0118] Other acid-labile groups can also be those where the hydrogen atom of the phenolic hydroxyl group is replaced by -CH2COO- (a tertiary saturated hydrocarbon group). In this case, the aforementioned tertiary saturated hydrocarbon group can be the same as the tertiary saturated hydrocarbon group used for the protection of the aforementioned phenolic hydroxyl group.

[0119] Furthermore, repeating unit B2 can be represented by the following formula (B2-2) (hereinafter also referred to as repeating unit B2-2). Since repeating unit B2-2 increases the dissolution rate of the exposure section, it is a useful option as a unit containing acid-inhibited groups that provides good performance for linewidth variations in the developing load. [Chemistry 62]

[0120] 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.

[0121] In formula (B2-2), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0122] In formula (B2-2), R32 and R33 are each an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. R32 and R33 may also bond to each other and form a ring together with the carbon atoms they bond to.

[0123] In formula (B2-2), R34 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.

[0124] In formula (B2-2), R35 can be a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms.

[0125] In formula (B2-2), A3 is a single bond, an enylphenyl, an enylnaphthyl, or *-C(=O)-O-A31-. A31 may also be an aliphatic enyl group with 1 to 20 carbon atoms, containing 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.

[0126] Ideal examples of repeating unit B2-2 can be listed below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 63]

[0127] [Chemistry 64]

[0128] The content of repeating unit B2 in all repeating units constituting the aforementioned polymer is preferably 5-95 mol%, and more preferably 20-80 mol%. Repeating unit B2 can be used alone or in combination of two or more types.

[0129] The aforementioned polymer may also contain at least one of the repeating units represented by the following formula (B3) (hereinafter also referred to as repeating unit B3), the repeating unit represented by the following formula (B4) (hereinafter also referred to as repeating unit B4), and the repeating unit represented by the following formula (B5) (hereinafter also referred to as repeating unit B5). [Chemistry 65]

[0130] In equations (B3) and (B4), d is 0, 1, 2, 3, 4, 5, or 6. e is 0, 1, 2, 3, or 4.

[0131] In formulas (B3) and (B4), R41 and R42 are independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 6 carbon atoms that can be substituted by a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that can be substituted by a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that can be substituted by a halogen atom. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxygen group, and saturated hydrocarbon carbonyl oxygen group can be any of the following: linear, branched, or cyclic. When d is 2 or more, each R41 can be the same or different from the others. When e is 2 or more, each R42 can be the same or different from the others.

[0132] In formula (B5), f1 is 0 or 1. f2 is 0, 1, or 2. When f2 is 0, it is a benzene skeleton; when it is 1, it is a naphthalene skeleton; and when it is 2, it is an anthracene skeleton. f3 is 0, 1, 2, 3, 4, or 5. When f2 is 0, f3 should preferably be 0, 1, 2, or 3; when f2 is 1 or 2, f3 should preferably be 0, 1, 2, 3, or 4.

[0133] In formula (B5), RA is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0134] In formula (B5), R43 can be a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxy group with 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group with 2 to 20 carbon atoms, a saturated hydrocarbon oxyalkyl 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. When f2 is 1 or 2, it can also be a hydroxyl group. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxyalkyl group, saturated hydrocarbon carbonyl oxyalkyl group, saturated hydrocarbon oxyalkyl group, and saturated hydrocarbon thioalkyl group can be any of the following: linear, branched, or cyclic. When f3 is 2 or more, each R43 can be the same or different.

[0135] 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 any of the following: linear, branched, or cyclic. Specific examples can be given as those illustrated in the description of A1 in formula (B1).

[0136] 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.

[0137] To improve etching resistance, the content of repeating units B3 to B5 should preferably be 5 mol% or more in all repeating units constituting the aforementioned polymer. Furthermore, the content of repeating units B3 to B5 in all repeating units constituting the aforementioned polymer should preferably be 25 mol% or less, preferably 20 mol% or less. Ideally, if the amount of units without functional groups, or with functional groups other than hydroxyl groups, is 25 mol% or less, there is no concern about developing defects. Repeating units B3 to B5 can be used alone or in combination of two or more.

[0138] If the aforementioned polymer contains repeating unit B1, repeating unit B2, and at least one of repeating units selected from B3 to B5, it is ideal to have both high etch resistance and excellent resolution. In this case, these repeating units should preferably contain 60 mol% or more, more preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more in all repeating units of the aforementioned polymer.

[0139] The aforementioned polymer may also contain at least one of the following: repeating unit represented by formula (B6) (hereinafter also referred to as repeating unit B6), repeating unit represented by formula (B7) (hereinafter also referred to as repeating unit B7), repeating unit represented by formula (B8) (hereinafter also referred to as repeating unit B8), repeating unit represented by formula (B9) (hereinafter also referred to as repeating unit B9), and repeating unit represented by formula (B10) (hereinafter also referred to as repeating unit B10). [Chemistry 66]

[0140] 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, 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, and this aliphatic alkyl group may also contain a halogen atom, hydroxyl group, ether bond, ester bond, or lactone ring. 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 is an alkyl group with 1 to 20 carbon atoms, and may also contain heteroatoms. 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 alkyl, phenyl alkyl, fluorinated phenyl alkyl, phenyl alkyl substituted with trifluoromethyl, *-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 alkyl, fluorinated phenyl, or phenyl substituted with trifluoromethyl, and 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.

[0141] Z21, Z51, and Z91 represent aliphatic alkyl groups that 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, 1,1-dimethylethane-1,2-diyl, pentane-1,5-diyl, 2-methylbutane-1,2-diyl, hexane-1,6-diyl, etc.; cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, cyclohexanediyl, etc.; and groups obtained by combining them.

[0142] Z71 and Z81 can also contain heteroatoms, and the extended hydrocarbon group can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. Specific examples are listed below, but are not limited to these. [Chemistry 67] In the formula, the dashed lines represent atomic bonds.

[0143] In formula (B6), R51 and R52 are each independently a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon group 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, secondary butyl, and tertiary butyl; cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 20 carbon atoms, such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 20 carbon atoms, such as cyclohexenyl; aryl groups with 6 to 20 carbon atoms, such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 20 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them, but preferably aryl. 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, and a portion of the -CH2- group of the hydrocarbon group can also 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, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0144] Furthermore, R51 and R52 can also bond to each other and form a ring together with the sulfur atoms they are bonded to. Specific examples of the aforementioned rings can be shown in the following formulas, etc. [Chemistry 68] In the formula, the dashed lines represent the atomic bonds between Z and Z4.

[0145] Specific examples of the cations in repeating unit B6 can be listed below, but are not limited thereto. Furthermore, in the following formula, RA is the same as described above. [Chemistry 69]

[0146] [Chemistry 70]

[0147] [Chemistry 71]

[0148] [Chemistry 72]

[0149] [Chemistry 73]

[0150] [Chemistry 74]

[0151] [Chemistry 75]

[0152] [Chemistry 76]

[0153] [Chemistry 77]

[0154] [Chemistry 78]

[0155] In formula (B6), M- represents a non-nucleophilic relative ion. The aforementioned non-nucleophilic relative ions are preferably halide ions, sulfonic acid anions, aceimine anions, and methylated acid anions. Specific examples of the aforementioned halide ions include chloride ions, bromide ions, etc. Specific examples of the aforementioned sulfonic acid anions (sulfonate ions) include: trifluoromethanesulfonate ions, 1,1,1-trifluoroethanesulfonate ions, nonafluorobutanesulfonate ions, and other fluoroalkyl sulfonate ions; toluenesulfonate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, 1,2,3,4,5-pentafluorobenzenesulfonate ions, and other aryl sulfonate ions; methanesulfonate ions, butanesulfonate ions, and other alkyl sulfonate ions, etc. Specific examples of the aforementioned amide acid anions (amide ions) include: bis(trifluoromethylsulfonyl)amide ions, bis(perfluoroethylsulfonyl)amide ions, bis(perfluorobutylsulfonyl)amide ions, etc. Specific examples of the aforementioned methylated acid anions (methylated ions) include: trifluoromethylsulfonyl methylated ions, trifluoroethylsulfonyl methylated ions, etc.

[0156] Other examples of the aforementioned non-nucleophilic relative ions can be listed as anions represented by any of the formulas (B6-1) to (B6-4). [Chemistry 79]

[0157] In formula (B6-1), Rfa is a fluorine atom, or a hydrocarbon group with 1 to 40 carbon atoms that may contain heteroatoms. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples can be listed and illustrated as examples of hydrocarbon groups represented by Rfa1 in the following formula (B6-1-1).

[0158] The anion represented by formula (B6-1) should preferably be represented by the following formula (B6-1-1). [Chemistry 80]

[0159] In formula (B6-1-1), Q1 and Q2 are independently hydrogen atoms, fluorine atoms, or fluorinated saturated hydrocarbon groups with 1 to 6 carbon atoms, respectively. To improve solvent solubility, at least one of them is preferably trifluoromethyl. m can be 0, 1, 2, 3, or 4, with 1 being particularly preferred. Rfa1 can also be a hydrocarbon group with 1 to 35 carbon atoms containing heteroatoms. The aforementioned heteroatoms are preferably oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms, etc., with oxygen atoms being more preferred. Considering the high resolution that can be obtained when forming fine patterns, the aforementioned hydrocarbon groups with 6 to 30 carbon atoms are particularly preferred.

[0160] 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, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecanyl, and eicosyl; cyclic saturated hydrocarbon groups with 3 to 35 carbon atoms, such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norcamphenyl, norcamphenylmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl; unsaturated aliphatic hydrocarbon groups with 2 to 35 carbon atoms, such as 2-propenyl and 3-cyclohexenyl; aryl groups with 6 to 35 carbon atoms, such as phenyl, 1-naphthyl, 2-naphthyl, and 9-enyl; aralkyl groups with 7 to 35 carbon atoms, such as benzyl and diphenylmethyl; and groups obtained by combining them.

[0161] 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, a portion of the -CH2- group in the hydrocarbon group can be replaced by a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. This can result in the presence of hydroxyl, fluorine, chlorine, bromine, iodine, cyano, nitro, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonate 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.

[0162] 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, it is preferable to be an ether bond or an ester bond, with an ester bond being even better.

[0163] Specific examples of anions represented by formula (B6-1) are shown below, but are not limited to these. Additionally, in the following formula, Q1 is the same as described above, and Ac is acetyl. [Chemistry 81]

[0164] [Chemistry 82]

[0165] [Chemistry 83]

[0166] [Chemistry 84]

[0167] [Chemistry 85]

[0168] [Chemistry 86]

[0169] [Chemistry 87]

[0170] [Chemistry 88]

[0171] [Chemistry 89]

[0172] [Chemistry 90]

[0173] In formula (B6-2), Rfb1 and Rfb2 are each independently a fluorine atom, or may contain heteroatoms of 1 to 40 carbon atoms, and are hydrocarbons. The aforementioned hydrocarbons may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples can be given and illustrated by the same example of the hydrocarbon represented by Rfa1 in formula (B6-1-1). Rfb1 and Rfb2 are preferably fluorine atoms or linear fluorinated alkyl groups having 1 to 4 carbon atoms. Furthermore, Rfb1 and Rfb2 can also bond to each other and form a ring together with the group they bond to (-CF2-SO2-N--SO2-CF2-). In this case, the group obtained by the mutual bonding of Rfb1 and Rfb2 should preferably be fluorinated ethyl or fluorinated propyl.

[0174] 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 group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given and illustrated by the same example as the hydrocarbon group represented by Rfa1 in formula (B6-1-1). Rfc1, Rfc2, and Rfc3 are preferably fluorine atoms or linear fluorinated alkyl groups with 1 to 4 carbon atoms. Furthermore, Rfc1 and Rfc2 can also be bonded to each other and form a ring together with the group they are bonded to (-CF2-SO2-C--SO2-CF2-). In this case, the group formed by the mutual bonding of Rfc1 and Rfc2 is preferably fluorinated ethyl or fluorinated propyl.

[0175] In formula (B6-4), Rfd is a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed and illustrated as hydrocarbon groups represented by Rfa1 in formula (B6-1-1).

[0176] Specific examples of anions represented by formula (B6-4) can be listed below, but are not limited to these. [Chemistry 91]

[0177] [Chemistry 92]

[0178] The aforementioned examples of non-nucleophilic relative ions can be further illustrated by anions having aromatic rings substituted with iodine or bromine atoms. Specific examples of such anions can be represented by the following formula (B6-5). [Chemistry 93]

[0179] In equation (B6-5), x is 1, 2, or 3. y is 1, 2, 3, 4, or 5. z is 0, 1, 2, or 3. However, 1 ≤ y + z ≤ 5. y should ideally be 1, 2, or 3, with 2 or 3 being better. z should ideally be 0, 1, or 2.

[0180] 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.

[0181] 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.

[0182] 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, and the linker may also contain oxygen, sulfur or nitrogen atoms.

[0183] 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-oxy group, a 2-20 carbon-1 hydrocarbon-carbonyl group, a 2-20 carbon-1 hydrocarbon-oxycarbonyl group, a 2-20 carbon-1 hydrocarbon-carbonyloxy group, or a 1-20 carbon-1 hydrocarbon-sulfonyloxy 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 having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl oxy group having 2 to 6 carbon atoms. RfeD is an aliphatic hydrocarbon group having 1 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl oxy group having 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. The aforementioned hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyl group, hydrocarbon oxycarbonyl group, hydrocarbon carbonyl oxy group, and hydrocarbon sulfonyl oxy group may be linear, branched, or cyclic. When x and / or z are 2 or more, each Rfe may be the same or different.

[0184] Among them, Rfe should preferably be a hydroxyl group, -N(RfeC)-C(=O)-RfeD, -N(RfeC)-C(=O)-O-RfeD, a fluorine atom, a chlorine atom, a bromine atom, a methyl group, a methoxy group, etc.

[0185] In formula (B6-5), Rf11 to Rf14 are independently hydrogen atoms, fluorine atoms, or trifluoromethyl groups, with at least one of them being a fluorine atom or a trifluoromethyl group. Furthermore, Rf11 and Rf12 can also combine to form a carbonyl group. It is particularly desirable for Rf13 and Rf14 to both be fluorine atoms.

[0186] Specific examples of anions represented by formula (B6-5) are shown below, but are not limited to these. Furthermore, in the following formula, XBI is the same as described above. [Chemistry 94]

[0187] [Chemistry 95]

[0188] [Chemistry 96]

[0189] [Chemistry 97]

[0190] [Chem. 98]

[0191] [Chemistry 99]

[0192] [Chemistry 100]

[0193] [Chemistry 101]

[0194] [Chemistry 102]

[0195] [Chemistry 103]

[0196] [Chemistry 104]

[0197] [Chemistry 105]

[0198] [Chemistry 106]

[0199] [Chemistry 107]

[0200] [Chemistry 108]

[0201] [Chemistry 109]

[0202] [Chemical 110]

[0203] [Chemistry 111]

[0204] [Chemistry 112]

[0205] [Chemistry 113]

[0206] [Chemistry 114]

[0207] [Chemistry 115]

[0208] [Chemistry 116]

[0209] The aforementioned non-nucleophilic relative ions may also be used: the fluorobenzenesulfonate anion bonded to an aromatic group containing an iodine atom as described in Japanese Patent No. 6648726, the anion having a mechanism of decomposition by acid as described in Japanese Patent No. 2021 / 200056 and Japanese Patent Application Publication No. 2021-70692, the anion having a cyclic ether group as described in Japanese Patent Application Publication No. 2018-180525 and Japanese Patent Application Publication No. 2021-35935, and the anion described in Japanese Patent Application Publication No. 2018-92159.

[0210] The aforementioned non-nucleophilic relative ions may also be used as follows: the bulky benzenesulfonic acid derivative anions without fluorine atoms 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 without fluorine atoms bonded to an aromatic group containing iodine atoms and described in Japanese Patent No. 6645464.

[0211] The aforementioned non-nucleophilic relative ions may also be used as follows: the anion of disulfonic acid as described in Japanese Patent Application Publication No. 2015-206932; the anion of sulfonamide or sulfenimide, which is different from sulfonic acid on one side as described in International Patent Application Publication No. 2020 / 158366; and the anion of carboxylic acid on one side as described in Japanese Patent Application Publication No. 2015-24989.

[0212] In equations (B7) and (B8), g1 and g2 are independently 0, 1, 2 or 3, and it is preferable to be 1.

[0213] 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.

[0214] 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. Among these, from a synthetic point of view, ether bond, ester bond, and carbonyl group are preferable, with ester bond and carbonyl group being even more preferred.

[0215] 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 them, Rf1 and Rf2 are preferably both fluorine atoms to improve the acid strength of the generated 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 them, to improve solvent solubility, at least one of Rf3 and Rf4 is preferably a trifluoromethyl group.

[0216] In formula (B8), Rf5 and Rf6 are independently hydrogen atoms, fluorine atoms, or fluorinated saturated hydrocarbon groups having 1 to 6 carbon atoms, respectively. However, not all of Rf5 and Rf6 are hydrogen atoms simultaneously. Among them, to improve solvent solubility, at least one of Rf5 and Rf6 should preferably be a trifluoromethyl group.

[0217] 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. Rf7 is preferably a fluorine atom, trifluoromethyl, difluoromethyl, trifluoromethoxy, difluoromethoxy, trifluoromethylthio, or difluoromethylthio, with fluorine atom, trifluoromethyl, or trifluoromethoxy being more preferred. When h2 is 2, 3, or 4, each Rf7 can be the same or different.

[0218] In formula (B9), R53 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 can be given similarly to those illustrated in the explanation of formula (Z-1) where the hydrocarbon group represents R1 to R9, but are not limited thereto. Furthermore, when h3 is 2, 3, or 4, each R53 can be the same or different.

[0219] Furthermore, when h3 is 2, 3, or 4, multiple R53 atoms can bond to each other and form a ring together 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, norbornene rings, adamantane rings, etc. Also, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- groups in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. The result can also include hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0220] Specific examples of the anion of repeating unit B7 can be listed below, but are not limited thereto. Additionally, in the following formula, RA is the same as described above, and Me is a methyl group. [Chemistry 117]

[0221] [Chemistry 118]

[0222] [Chemistry 119]

[0223] [Chemistry 120]

[0224] [Chemistry 121]

[0225] [Chemistry 122]

[0226] [Chemistry 123]

[0227] [Chemistry 124]

[0228] [Chemistry 125]

[0229] [Chemistry 126]

[0230] [Chemistry 127]

[0231] [Chemistry 128]

[0232] [Chemistry 129]

[0233] Specific examples of anions in the repeating unit B8 can be listed below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 130]

[0234] [Chemistry 131]

[0235] [Chemistry 132]

[0236] [Chemistry 133]

[0237] [Chemistry 134]

[0238] [Chemistry 135]

[0239] [Chemistry 136]

[0240] [Chemistry 137]

[0241] [Chemistry 138]

[0242] [Chemistry 139]

[0243] [Chemistry 140]

[0244] Specific examples of the anion of repeating unit B9 can be listed below, but are not limited thereto. Furthermore, in the following formula, RA is the same as described above. [Chemistry 141]

[0245] [Chemistry 142]

[0246] [Chemistry 143]

[0247] [Chemistry 144]

[0248] [Chemistry 145]

[0249] [Chemistry 146]

[0250] [Chemistry 147]

[0251] [Chemistry 148]

[0252] [Chemistry 149]

[0253] [Chemistry 150]

[0254] [Chemistry 151]

[0255] [Chemistry 152]

[0256] [Chemistry 153]

[0257] [Chemistry 154]

[0258] [Chemistry 155]

[0259] [Chemistry 156]

[0260] [Chemistry 157]

[0261] Specific examples of anions in the repeating unit B10 can be listed below, but are not limited to these. Furthermore, in the following formula, RA is the same as described above. [Chemistry 158]

[0262] In formulas (B7) to (B10), A+ is a ium cation. The aforementioned ium cation is preferably a strontium cation or a zirconia cation. Specific examples of the aforementioned strontium cation may be listed and illustrated as examples of the strontium cation represented by formula (Z-1), or as examples of the strontium cation represented by formula (Z-4), but are not limited thereto. Specific examples of the aforementioned zirconia cation may be listed and illustrated as examples of the zirconia cation represented by formula (Z-2), but are not limited thereto.

[0263] The specific structures of repeating units B6 to B10 can be listed as any combination of the aforementioned anions and cations.

[0264] Repeating units B6-B10 are units that generate acid using high-energy radiation. It is believed that by incorporating these units into the polymer, a pattern with moderately suppressed acid diffusion and reduced LER (Leakage Rate) can be obtained. Furthermore, it is believed that by incorporating these units into the polymer, during vacuum baking, the phenomenon of acid evaporation from the exposed areas and re-adhesion to the unexposed areas is suppressed, and this is effective in reducing LER and minimizing shape degradation caused by undesirable film loss in the unexposed areas.

[0265] Among the repeating units B6 to B10, the units that are more ideal for processing blank photomasks, considering the design to suppress acid diffusion and the optimal acid strength in terms of the acid unstable groups of the polymer, are repeating units B7 to B10, and repeating units B8, B9 and B10 are even better.

[0266] Among all the repeating units of the aforementioned polymer, repeating units B6 to B10 are preferably introduced in the range of 0.1 to 30 mol%, and more preferably in the range of 0.5 to 20 mol%. Repeating units B6 to B10 can be used alone or in combination of two or more.

[0267] Of all the repeating units in the aforementioned polymer, the content of repeating units having an aromatic ring skeleton should preferably be 65 mol% or more, preferably 75 mol% or more, and even more preferably 85 mol% or more. When repeating units B6 to B10 are not included, all units should preferably have an aromatic ring skeleton.

[0268] The aforementioned polymers may also contain commonly used (meth)acrylate units protected by acid-labile groups, (meth)acrylate units with lactone structures, hydroxyl groups other than phenolic hydroxyl groups, or other close-knit groups. These repeating units can be used to fine-tune the properties of the resist film, but they may also be omitted.

[0269] Examples of (meth)acrylate units having the aforementioned binding groups 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 as auxiliary units to provide adhesion to the substrate and to adjust solubility. [Chemistry 159]

[0270] In formulas (B11) to (B13), RA is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R61 is -O- or a methylene group. R62 is a hydrogen atom or a hydroxyl group. R63 is a saturated hydrocarbon group with 1 to 4 carbon atoms. i is 0, 1, 2, or 3.

[0271] When the polymer contains repeating units B11 to B13, their content should preferably be 0 to 20 mol%, or more preferably 0 to 10 mol%, among all repeating units in the aforementioned polymer. Repeating units B11 to B13 can be used alone or in combination of two or more.

[0272] The aforementioned polymers can be synthesized by copolymerizing monomers with protecting groups as needed using known methods, followed by deprotection reactions as required. There are no particular limitations on the copolymerization reaction; free radical polymerization and anionic polymerization are preferred. These methods can be referenced in Japanese Patent Application Publication No. 2004-115630.

[0273] The weight-average molecular weight (Mw) of the aforementioned polymer is preferably between 1,000 and 50,000, and more preferably between 2,000 and 20,000. If Mw is above 1,000, there is no concern about the phenomenon of rounding at the top of the pattern, resulting in reduced resolution and LER degradation, as is common in conventional methods. On the other hand, if Mw is below 50,000, there is no concern about LER degradation when forming patterns with a linewidth of 100 nm or less. In addition, in this invention, Mw is a polystyrene conversion value determined by gel permeation chromatography (GPC) using THF or DMF as solvents.

[0274] The molecular weight distribution (Mw / Mn) of the aforementioned polymer is 1.0~2.0, preferably 1.0~1.9, and even better is a narrow dispersion of 1.0~1.8. With such a narrow dispersion, there will be no foreign matter generated on the pattern after development, or the pattern shape will deteriorate.

[0275] Furthermore, regarding the aforementioned basic polymer design, the dissolution rate of the alkaline developer should ideally be below 10 nm / min, preferably below 7 nm / min, and even more preferably below 5 nm / min. In advanced generations, when the coating film applied to the substrate is in the thin film field (below 100 nm), the impact on pattern film loss during alkaline development becomes greater. When the polymer's alkaline dissolution rate exceeds 10 nm / min, the pattern will break down, and it will become impossible to form fine patterns. This is particularly noticeable in the fabrication of photomasks requiring defect-free results, where there is a tendency for stronger development processes. In addition, in this invention, the dissolution rate of the basic polymer to the alkaline developer is determined by the amount of 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 using a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.

[0276] (B) The base polymer of the component may also contain other polymers besides those mentioned above. Other polymers may be base polymers commonly used as inhibitor components. There are no particular limitations on the content of other polymers as long as they do not impair the effects of the present invention.

[0277] [(C) Photoacid Generator] The chemical amplification positive inhibitor composition of this invention may also contain a photoacid generator as component (C). There are no particular limitations on the aforementioned photoacid generator, which is a compound that produces acid upon irradiation by high-energy rays. Ideal photoacid generators include strontium salts, ferrous salts, sulfonyldiazomethane, N-sulfonoxyimide, and oxime-O-sulfonate type acid generators.

[0278] Specific examples of the aforementioned photoacid generators include: nonafluorobutane sulfonate, partially fluorinated sulfonates described in paragraphs

[0247] to

[0251] of Japanese Patent No. 5706778, partially fluorinated sulfonates described in paragraphs

[0261] to

[0265] of Japanese Patent No. 5852851, and those described in paragraphs

[0122] to

[0142] of Japanese Patent No. 4858714 and paragraphs

[0080] to

[0081] of Japanese Patent No. 5368270. Furthermore, the anion of the photoacid generator can also be exemplified as the anion represented by M- in formula (B6). Among these, aryl sulfonate or alkyl sulfonate type photoacid generators are more desirable because they can generate an acid of appropriate strength that deprotects the unstable acid group of repeating unit B2.

[0279] Furthermore, in order to improve the effects of LER and CDU by combining the aforementioned photoacid generator with the quencher of component (A), the pKa of the acid generated from the photoacid generator should be -3.0 or higher, preferably in the range of -3.0 to 2.0, and more preferably in the range of -2.0 to 1.5.

[0280] The aforementioned photoacid generator is preferably a salt compound having anions as shown below. [Chemistry 160]

[0281] The anion of the aforementioned photoacid generator should also be as described in Japanese Patent No. 7032549

[0220] ~

[0225] , Japanese Patent No. 6248882

[0027] ~

[0029] , Japanese Patent No. 7067271

[0028] ~

[0029] , Japanese Patent Application Publication No. 2023-177038

[0039] ~

[0066] , and Japanese Patent Application Publication No. 2024-077330

[0229] ~

[0231] .

[0282] The anion of the aforementioned photoacid generator should also preferably be a salt compound having the anion shown below. [Chemistry 161]

[0283] [Chemistry 162]

[0284] [Chemistry 163]

[0285] [Chemistry 164]

[0286] [Chemistry 165]

[0287] [Chemistry 166]

[0288] [Chemistry 167]

[0289] [Chemistry 168]

[0290] [Chemistry 169]

[0291] [Chemistry 170]

[0292] [Chemistry 171]

[0293] [Chemistry 172]

[0294] [Chemistry 173]

[0295] [Chemistry 174]

[0296] [Chemistry 175]

[0297] [Chemistry 176]

[0298] [Chemistry 177]

[0299] [Chemistry 178]

[0300] [Chemistry 179]

[0301] [Chemistry 180]

[0302] [Chemistry 181]

[0303] [Chemistry 182]

[0304] [Chemistry 183]

[0305] [Chemistry 184]

[0306] [Chemistry 185]

[0307] [Chemistry 186]

[0308] The cations that pair with the aforementioned anions can be exemplified as strontium cations represented by formula (Z-1) and strontium cations represented by formula (Z-4), or as monium cations represented by formula (Z-2).

[0309] When the chemically amplified positive inhibitor composition of the present invention contains (C) a photoacid generator, its content relative to 80 parts by mass of (B) the base polymer is preferably 1 to 30 parts by mass, and more preferably 2 to 20 parts by mass. Furthermore, when the base polymer contains repeating units B6 to B13 (i.e., polymer-bonded acid generators), the addition of (C) the acid generator can be omitted. (C) The acid generator can be used alone or in combination of two or more types.

[0310] In the chemical amplification positive inhibitor composition of the present invention, regarding the quencher in component (A) and the photoacid generator in component (C), the content ratio of the photoacid generator to the quencher ((C) / (A)) by mass is preferably less than 6, more preferably less than 5, and even more preferably less than 4. If the content ratio of the photoacid generator to the quencher in the aforementioned chemical amplification positive inhibitor composition is within the aforementioned range, acid diffusion can be sufficiently suppressed, and excellent resolution and dimensional uniformity can be obtained.

[0311] [(D) Organic solvent] The chemical amplification positive inhibitor composition of the present invention may also contain an organic solvent as component (D). There are no particular limitations as long as the aforementioned organic solvent is capable of dissolving each component. Examples of such organic solvents include, for instance, ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone as described in paragraphs

[0144] to

[0145] of Japanese Patent Application Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; and propylene glycol monomethyl ether (PGME) and ethylene glycol monomethyl ether. Ethers such as propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate (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 monotert-butyl 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 can be added to accelerate the deprotection reaction of the acetal. Specifically, diethylene glycol, propylene glycol, glycerol, 1,4-butanediol, and 1,3-butanediol can also be added.

[0312] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, PGME, cyclohexanone, EL, γ-butyrolactone, and their mixed solvents are preferred.

[0313] When the chemical amplification positive inhibitor composition of the present invention contains (D) organic solvent, its content relative to 80 parts by mass of (B) base polymer is preferably 200-10000 parts by mass, and more preferably 400-5000 parts by mass. (D) organic solvent can be used alone or in combination of two or more.

[0314] [(E) Polymers containing fluorine atoms] In the chemical amplification positive resist composition of the present invention, in order to achieve high contrast, suppress chemical flare of acid during high-energy ray irradiation, shield the mixing of acid from the antistatic film during the process of coating the antistatic film material onto the resist film, and suppress unintended and unnecessary pattern degradation, it may also contain at least one of the repeating units represented by the following formula (E1) (hereinafter also referred to as repeating unit E1), repeating units represented by the following formula (E2) (hereinafter also referred to as repeating unit E2), repeating units represented by the following formula (E3) (hereinafter also referred to as repeating unit E3), and repeating units represented by the following formula (E4) (hereinafter also referred to as repeating unit E4), and may further contain a polymer containing fluorine atoms as component (E) selected from at least one of the repeating units represented by the following formula (E5) (hereinafter also referred to as repeating unit E5) and repeating units represented by the following formula (E6) (hereinafter also referred to as repeating unit E6). The aforementioned polymers containing fluorine atoms also function as surfactants, preventing insoluble substances that may be generated during the development process from re-attaching to the substrate, thus also having an effect on development defects. [Chemistry 187]

[0315] In formulas (E1) to (E6), 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. RB are independently hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups. RC are independently hydrogen atoms or methyl groups. R101, R102, R104, and R105 are independently hydrogen atoms or saturated hydrocarbon groups with 1 to 10 carbon atoms. R103, R106, R107, and R108 are independently hydrogen atoms, hydrocarbon groups with 1 to 15 carbon atoms, fluorinated hydrocarbon groups with 1 to 15 carbon atoms, or acid-unstable groups. When R103, R106, R107, and R108 are hydrocarbon groups or fluorinated hydrocarbon groups, ether bonds or carbonyl groups may be inserted between carbon-carbon bonds. R109 is a hydrogen atom, or a linear or branched hydrocarbon group with 1 to 5 carbon atoms, which may also have a heteroatom-containing group inserted between carbon-carbon bonds. R110 is a linear or branched hydrocarbon group with 1 to 5 carbon atoms, which may also have a heteroatom-containing group inserted between carbon-carbon bonds. R111 is a saturated hydrocarbon group with 1 to 20 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom, and part of the -CH2- of the aforementioned saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. X1 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. X2 is a single bond, *-C(=O)-O- or *-C(=O)-NH-. * represents an atomic bond with a carbon atom of the main chain. X3 is a single bond, -O-, *-C(=O)-O-X31-X32-, or *-C(=O)-NH-X31-X32-. X31 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms. X32 is a single bond, ester bond, ether bond, or sulfonamide bond. * represents an atomic bond with a carbon atom in the main chain.

[0316] In formulas (E1) and (E2), R101, R102, R104, and R105 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, secondary butyl, tertiary butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; and cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, and norbornel. Among these, saturated hydrocarbon groups with 1 to 6 carbon atoms are preferred.

[0317] In formulas (E1) to (E4), the hydrocarbon groups represented by R103, R106, R107, and R108, having 1 to 15 carbon atoms, can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 15 carbon atoms, alkenyl groups with 2 to 15 carbon atoms, and alkynyl groups with 2 to 15 carbon atoms, preferably alkyl groups with 1 to 15 carbon atoms. The aforementioned alkyl groups can include those listed above, as well as: 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, n-pentadecanyl, etc. Furthermore, fluorinated hydrocarbon groups can be groups in which some or all of the hydrogen atoms of the carbon atoms bonded to the aforementioned hydrocarbon groups are replaced by fluorine atoms.

[0318] In formula (E4), X1 represents a (k+1) valence hydrocarbon group having 1 to 20 carbon atoms, which can be a group obtained by further removing k hydrogen atoms from an alkyl group having 1 to 20 carbon atoms or a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Furthermore, X1 represents a (k+1) valence fluorinated hydrocarbon group having 1 to 20 carbon atoms, which can be a group formed by replacing at least one hydrogen atom of the aforementioned (k+1) valence hydrocarbon group with a fluorine atom.

[0319] Specific examples of repeating units E1 to E4 can be listed below, but are not limited to these. Furthermore, in the following formula, RB is the same as described above. [Chem.188]

[0320] [Chemistry 189]

[0321] [Chemistry 190]

[0322] In formula (E5), R109 and R110 represent hydrocarbon groups with 1 to 5 carbon atoms, which can be alkyl, alkenyl, alkynyl, etc., and preferably alkyl. Examples of the aforementioned alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, n-pentyl, etc. Furthermore, heteroatoms containing oxygen, sulfur, nitrogen, etc., can also be inserted between the carbon-carbon bonds of the aforementioned hydrocarbon groups.

[0323] In formula (E5), -OR109 should preferably be a hydrophilic group. In this case, R109 should preferably be a hydrogen atom, an alkyl group with 1 to 5 carbon atoms interposed between carbon-carbon bonds, etc.

[0324] In formula (E5), X2 is preferably *-C(=O)-O- or *-C(=O)-NH-. Furthermore, RC is preferably methyl. The presence of a carbonyl group in X2 improves the acid capture ability from 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 stability over time, without degradation of resolution or pattern shape.

[0325] Repeating unit E5 can be listed as shown below, but is not limited to these. Additionally, in the following formula, RC is the same as described above. [Chemistry 191]

[0326] [Chemistry 192]

[0327] In formula (E6), X3 represents a saturated hydrocarbon group with 1 to 10 carbon atoms, which can be linear, branched, or cyclic. Specific examples include: methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, 1,1-dimethylethane-1,2-diyl, etc.

[0328] In formula (E6), R111 represents a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom. It can be any of the following: linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms or cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom.

[0329] Repeating unit E6 can be listed as shown below, but is not limited to these. Additionally, in the following formula, RC is the same as described above. [Chemistry 193]

[0330] [Chemistry 194]

[0331] [Chemistry 195]

[0332] [Chemistry 196]

[0333] The content of repeating units E1 to E4 in the aforementioned polymer containing fluorine atoms is preferably 15 to 95 mol%, and more preferably 20 to 85 mol%. The content of repeating units E5 and / or E6 in the aforementioned polymer containing fluorine atoms is preferably 5 to 85 mol%, and more preferably 15 to 80 mol%. Repeating units E1 to E6 can be used alone or in combination of two or more.

[0334] (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, their content should preferably be 50 mol% or less among all repeating units of the aforementioned polymers containing fluorine atoms.

[0335] (E) Polymers containing fluorine atoms can be synthesized by copolymerizing monomers with protecting groups as needed using known methods, followed by deprotection reactions as required. There are no particular limitations on the copolymerization reaction; free radical polymerization and anionic polymerization are preferred. For these methods, please refer to Japanese Patent Application Publication No. 2004-115630.

[0336] (E) The Mw of fluorine-containing polymers should preferably be 2000~50000, with 3000~20000 being more preferred. 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, the Mw / Mn ratio of (E) fluorine-containing polymers should preferably be 1.0~2.2, with 1.0~1.7 being more preferred.

[0337] When the chemical amplification positive inhibitor composition of the present invention contains a (E) fluorine-containing polymer, its content relative to 80 parts by mass of the (B) base polymer is preferably 0.01 to 30 parts by mass, and more preferably 0.1 to 20 parts by mass. The (E) fluorine-containing polymer can be used alone or in combination of two or more.

[0338] [(F) Other quenching agents] The chemically amplified positive resist composition of the present invention may also contain other quenching agents besides component (A) as component (F) as needed. This suppresses the diffusion rate of acid generated from the acid-generating agent into the resist film, and when a substrate with its outermost surface made of a chromium-containing material is used as the substrate, the effect of acid generated within the resist film on the chromium-containing material can still be suppressed.

[0339] Other quenching agents mentioned above include conventional basic compounds. Conventional basic compounds include: primary, secondary, and tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds with carboxyl groups, nitrogen-containing compounds with sulfonyl groups, nitrogen-containing compounds with hydroxyl groups, nitrogen-containing compounds with hydroxyphenyl groups, alcoholic nitrogen-containing compounds, amides, amides, and carbamates. In particular, the primary, secondary, and tertiary 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 No. 3790649, are particularly preferred. Ideal examples include: tris(2-(methoxymethoxy)ethyl)amine, tris(2-(methoxymethoxy)ethyl)amine-N-oxide, dibutylaminobenzoic acid, α-line derivatives, imidazole derivatives, etc. By adding such basic compounds, the diffusion rate of acid in the resist film can be further suppressed, or the shape can be modified, for example.

[0340] Furthermore, other quenching agents mentioned above include onium salts such as strontium salts, ferric salts, and ammonium salts of α-unfluorinated carboxylic acids, as described in Japanese Patent Application Publication No. 2008-158339. α-fluorinated sulfonic acids, amide acids, or methylated acids are necessary to deprotect unstable acid groups, releasing α-unfluorinated carboxylic acids through salt exchange with α-unfluorinated onium salts. Since α-unfluorinated carboxylic acids hardly undergo deprotection reactions, they function as quenching agents.

[0341] Onium salts of unfluorinated carboxylic acids at the α-position can be represented by, for example, those indicated by the following formula (F1). [Chemistry 197]

[0342] In formula (F1), R201 is a hydrogen atom or a hydrocarbon group with 1 to 40 carbon atoms that may contain heteroatoms, except that the hydrogen atom of the carbon atom bonded to the α position of the carboxyl group is replaced by a fluorine atom or a fluoroalkyl group.

[0343] R201 indicates that the hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 40 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, secondary butyl, tertiary butyl, n-pentyl, tertiary pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms, such as 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 groups with 2 to 4 carbon atoms. Alkenyl groups with 0 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-tributylphenyl, 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.

[0344] 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, and a portion of the -CH2- group of the hydrocarbon group can also 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.

[0345] In formula (F1), MqA+ represents an onium cation. The aforementioned onium cation is preferably a strontium cation, a ferrophosphate cation, or an ammonium cation, with strontium or ferrophosphate being more preferred. Specific examples of the aforementioned strontium cation can be listed and illustrated as examples of the strontium cation represented by formula (Z-1) and formula (Z-4). Specific examples of the aforementioned ferrophosphate cation can be listed and illustrated as examples of the ferrophosphate cation represented by formula (Z-2). Specific examples of the aforementioned ammonium cation can be listed and illustrated as examples of the ammonium cation represented by formula (Z-3).

[0346] The anions of onium salts represented by formula (F1) can be listed below, but are not limited to these. [Chemistry 198]

[0347] [Chemistry 199]

[0348] [Chemistry 200]

[0349] The aforementioned quenching agent can also ideally be a strontium salt of a carboxylic acid containing an iodinated benzene ring, represented by the formula (F2). [Chemical Engineering 201]

[0350] In equation (F2), s is 1, 2, 3, 4, or 5. t is 0, 1, 2, or 3. However, 1 ≤ s + t ≤ 5. u is 1, 2, or 3.

[0351] In formula (F2), R211 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 2-6 carbon saturated hydrocarbon carbonyl oxygen group, or a 1-4 carbon saturated hydrocarbon sulfonyl oxygen group, or -N(R211A)-C(=O)-R211B or -N(R211A)-C(=O)-O-R211B. R211A is a hydrogen atom or a 1-6 carbon saturated hydrocarbon group. R211B 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 R211 can be the same or different.

[0352] In formula (F2), L21 is a single bond or a (u+1) valent linkage with 1 to 20 carbon atoms, and may also contain at least one of the following: ether bond, carbonyl group, ester bond, amide bond, sulfonyl lactone ring, amide ring, carbonate bond, halogen atom, hydroxyl group, and carboxyl group. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyl oxy group, and saturated hydrocarbon sulfonyl oxy group may be linear, branched, or cyclic.

[0353] In formula (F2), R212, R213, and R214 are each independently a halogen atom or a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, 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 may be substituted with hydroxyl, carboxyl, halogen, oxy, cyano, nitro, sulfonyl lactone ring, sulfonyl, or strontium-containing groups, and a portion of the -CH2- group in the aforementioned hydrocarbon groups may be substituted with ether, ester, carbonyl, amide, carbonate, or sulfonate bonds. Additionally, R212 and R213 may be bonded to each other and form a ring together with the sulfur atoms they are bonded to.

[0354] Specific examples of compounds represented by formula (F2) can be found in Japanese Patent Application Publication No. 2017-219836. Compounds represented by formula (F2) have high sensitization effects due to their high absorption and also have high acid diffusion control effects.

[0355] The aforementioned quenching agent can also be represented by a nitrogen-containing carboxylate compound with the following formula (F3). [Chemical Engineering 202]

[0356] In formula (F3), R221 to R224 are independently hydrogen atoms, -L22-CO2-, or may contain heteroatoms and are hydrocarbon groups with 1 to 20 carbon atoms. R221 and R222, R222 and R223, or R223 and R224 may also bond to each other and form a ring together with the carbon atoms they are bonded to. L22 is a single bond or may contain heteroatoms and are hydrocarbon groups with 1 to 20 carbon atoms. R225 is a hydrogen atom or may contain heteroatoms and are hydrocarbon groups with 1 to 20 carbon atoms.

[0357] In formula (F3), ring Rr is a ring containing carbon atoms and nitrogen atoms of 2 to 6 carbons. Part or all of the hydrogen atoms bonded to the carbon atoms in this ring may be replaced by hydrocarbon groups of 1 to 20 carbons, or -L22-CO2-. Part of the -CH2- group in this ring may also be replaced by sulfur, oxygen, or nitrogen atoms. The aforementioned ring can be an alicyclic or aromatic ring, and preferably a 5- or 6-membered ring. Specific examples include: pyridine ring, pyrrole ring, pyrrolidinium ring, piperidine ring, pyrazole ring, imidazoline ring, pyrazine ring, pyrimidine ring, pyrazine ring, imidazoline ring, pyrazolium ring, thiazole ring, pyrazine ring, thiazoline ring, triazole ring, etc.

[0358] The carboxylic acid salt represented by formula (F3) has at least one -L22-CO2- group. That is, at least one of R221 to R224 is -L22-CO2-, and / or at least one of the hydrogen atoms of the carbon atom bonded to the ring Rr is replaced by -L22-CO2-.

[0359] In formula (F3), MqB+ is a strontium cation, a monium cation, or an ammonium cation, preferably a strontium cation. Specific examples of the aforementioned strontium cations can be listed and illustrated as specific examples of strontium cations represented by formula (Z-1) and formula (Z-4).

[0360] The anions of compounds represented by formula (F3) can be listed below, but are not limited to these. [Chemical Engineering 203]

[0361] [Chemical 204]

[0362] [Chemical Engineering 205]

[0363] [Chemical Engineering 206]

[0364] [Chemical 207]

[0365] [Chemical Engineering 208]

[0366] Furthermore, the aforementioned quenching agents can also be betaine-type compounds made of weak acids. Specific examples are listed below, but are not limited to these. [Chemical Engineering 209]

[0367] The aforementioned quenchers can be further exemplified by polymer-type quenchers disclosed in Japanese Patent Application Publication No. 2008-239918. These quenchers enhance the rectangularity of the resist pattern by aligning to the surface of the resist film. Polymer-type quenchers also reduce film loss and dome-shaped patterns when using protective films for immersion exposure.

[0368] When the chemical amplification positive inhibitor composition of the present invention contains other quenchers (F), their content relative to 80 parts by mass of the aforementioned (B) base polymer is preferably 0 to 50 parts by mass, and more preferably 0.1 to 40 parts by mass. (F) Other quenchers may be used alone or in combination of two or more.

[0369] (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. Many examples of the aforementioned surfactants are known, such as those described in Japanese Patent Application Publication No. 2004-115630, and can be referred to and selected from them. When the chemically amplified positive resist composition of the present invention contains surfactant (G), its content is preferably 0 to 5 parts by mass relative to 80 parts by mass of the base polymer (B). Surfactant (G) can be used alone or in combination of two or more.

[0370] [Resistant Pattern Formation Method] The resist pattern forming method of the present invention includes the following steps: A resist film is formed on a substrate using the aforementioned chemically amplified positive resist composition. The resist film was irradiated with high-energy rays to form a pattern (i.e., the resist film was exposed to high-energy rays), and The resist film with the previously irradiated pattern was developed using an alkaline developer.

[0371] The aforementioned substrate can be, for example, substrates used in integrated circuit manufacturing (Si, SiO, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective films, etc.) or substrates used in transmissive or reflective shielding circuit manufacturing (Cr, CrO, CrON, MoSi2, Si, SiO, SiO2, SiON, SiONC, CoTa, NiTa, TaBN, SnO2, etc.). On the aforementioned substrate, the aforementioned chemically amplified positive resist composition is coated with a film thickness of 0.03~2μm using methods such as spin coating, and then pre-baked on a hot plate, preferably at 60~150°C for 1~20 minutes, and more preferably at 80~140°C for 1~10 minutes, to form a resist film.

[0372] 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.), EUV, X-rays, gamma rays, synchrotron radiation, and EB. In this invention, EUV or EB is preferred for exposure.

[0373] When using ultraviolet light, far-ultraviolet light, excimer laser light, EUV, X-rays, gamma rays, or synchrotron radiation, the aforementioned high-energy rays are applied using a shield to form the desired pattern, with irradiation at an exposure dose preferably of 1~500 mJ / cm², and more preferably 10~400 mJ / cm². When using EB, to form the desired pattern, irradiation is performed directly with an exposure dose preferably of 1~500 μC / cm², and more preferably 10~400 μC / cm².

[0374] In addition to the usual exposure methods, wetting can also be used between a mask and a resist film, depending on the situation. In this case, a water-insoluble protective film can also be used.

[0375] Then, expose and bake on a heating plate at a temperature of 60-150°C for 1-20 minutes, preferably 80-140°C for 1-10 minutes (PEB).

[0376] Subsequently, a developer solution of 0.1-5% by mass, preferably 2-3% by mass, such as TMAH, is used. Common methods such as dip, immersion, and spray are employed for development, preferably for 0.1-3 minutes, and more preferably 0.5-2 minutes, thereby forming the desired pattern on the substrate.

[0377] Furthermore, the chemically amplified positive resist composition of the present invention is particularly useful for forming patterns with good resolution and low LER (Leadership Effect). Also, the chemically amplified positive resist composition of the present invention is particularly useful for pattern formation on substrates made of materials whose surfaces are prone to pattern peeling and damage due to difficulty in achieving good adhesion of the resist pattern. Examples of such substrates include: substrates with a chromium film sputtered on the outermost surface, substrates containing a chromium compound selected from one or more light elements selected from oxygen, nitrogen, and carbon, and substrates containing SiO, SiOx, tantalum compounds, molybdenum compounds, cobalt compounds, nickel compounds, tungsten compounds, and tin compounds in the outermost layer. The chemically amplified positive resist composition of the present invention is particularly useful for pattern formation using a blank photomask as the substrate. In this case, the blank photomask can be either transmissive or reflective.

[0378] Regarding transmissive blank masks, blank masks with a chromium-based material as the light-shielding film can be used as blank masks for binary masks or blank masks for phase-shifting masks. When used as a blank mask for binary masks, it can have an anti-reflective layer and a light-shielding layer made of chromium-based materials as the light-shielding film; it can also have the entire surface anti-reflective film made of chromium-based materials, or only the outermost layer of the surface anti-reflective film made of chromium-based materials, with the remaining portion being, for example, a silicon-based compound material that may also contain transition metals. Furthermore, when used as a blank mask for phase-shifting masks, a blank mask for phase-shifting masks with a chromium-based light-shielding film on the phase-shifting film can be considered.

[0379] The aforementioned blank photomask with a chromium-based material as the outermost layer is well known as conventional technology, as exemplified in Japanese Patent Application Publication No. 2008-26500, Japanese Patent Application Publication No. 2007-302873, or the like. Detailed descriptions are omitted. For example, when constructing a light-shielding film with an anti-reflective layer and a light-shielding layer using a chromium-based material, a film structure as described below can be used.

[0380] When forming a light-shielding film with an anti-reflective layer and a light-shielding layer using chromium-based materials, the layer structure can be constructed by sequentially stacking the anti-reflective layer and the light-shielding layer from the surface side, or by sequentially stacking the anti-reflective layer, the light-shielding layer, and the anti-reflective layer. Furthermore, the anti-reflective layer and the light-shielding layer can each be multi-layered, and the composition of the layers with different compositions can vary discontinuously or continuously. The chromium-based materials used can be metallic chromium or materials containing light elements such as oxygen, nitrogen, and carbon. Specifically, materials that can be used include: metallic chromium, chromium oxide, chromium nitride, chromium carbide, chromium nitride oxide, chromium carbide oxide, chromium carbide nitride, and chromium carbide nitride oxide.

[0381] Furthermore, a reflective blank mask comprises: a substrate, and a multilayer reflective film formed on one of the main surfaces (outer surface side) of the substrate, specifically a multilayer reflective film that reflects exposure light such as EUV light, and an absorber film formed on the multilayer reflective film, specifically an absorber film that absorbs exposure light such as EUV light and reduces reflectivity. From the reflective blank mask (EUV reflective blank mask), a reflective mask (EUV reflective mask) with an absorber pattern (pattern of absorber film) formed by patterning the absorber film can be manufactured. The wavelength of EUV light used in EUV lithography is 13~14nm, typically light with a wavelength of about 13.5nm.

[0382] The multilayer reflective film is typically disposed in contact with one of the main surfaces of the substrate. However, without compromising the effectiveness of the invention, a base film may also be disposed between the substrate and the multilayer reflective film. The absorber film may be formed in contact with the multilayer reflective film, or a protective film (protective film of the multilayer reflective film) may be disposed between the multilayer reflective film and the absorber film, preferably in contact with the multilayer reflective film. The protective film can be used to protect the multilayer reflective film during cleaning, correction, and other processing. Furthermore, the protective film is preferably designed to protect the multilayer reflective film and prevent oxidation of the multilayer reflective film when the absorber film is patterned by etching. Alternatively, a conductive film for electrostatically holding the reflective mask in the exposure apparatus may be disposed on the side opposite to one of the main surfaces of the substrate, i.e., the other main surface (the inner surface side), preferably in contact with the other main surface. Furthermore, here, one main surface of the substrate is defined as the outer surface side and the upper side, and the other main surface is defined as the inner surface side and the lower side. However, the outer and inner surfaces, as well as the upper and lower sides, are defined for ease of explanation. One main surface and the other main surface can be either of the two main surfaces (film forming surfaces) in the substrate, and the outer and inner surfaces, as well as the upper and lower sides, can be interchanged. More specifically, it can be formed using Japanese Patent Application Publication No. 2021-139970 or by a method exemplified therein as a conventional technique.

[0383] According to the resist patterning method of the present invention, even when using a substrate (e.g., a blank photomask) whose outermost surface is made of a material that easily affects the shape of the resist pattern, such as a chromium- or silicon-containing material, the chemically amplified positive resist composition of the present invention can still efficiently control acid diffusion at the substrate interface, thereby forming a pattern with high resolution, pattern fidelity, and improved LER and dose tolerance. [Example]

[0384] The present invention will be specifically described below with examples of synthesis, embodiments, and comparative examples, but the present invention is not limited to the following embodiments. Furthermore, the apparatus used is described below. MALDI TOF-MS: S3000 manufactured by Nippon Electronics Co., Ltd.

[0385] [1] Synthesis of onion salts [Synthetic Example 1-1] Synthesis of Onium Salt SQ-1 [Chemical 210]

[0386] Under nitrogen atmosphere, compound SM-1 (8.2 g), sodium nitrate (1.7 g), dichloromethane (40 g), and water (10 g) were added. After stirring for 15 minutes, the organic layer was separated and washed with water, followed by vacuum concentration. Methyl isobutyl ketone (50 g) was added to the concentrate and azeotropic dehydration was performed. Diisopropyl ether was further added to wash the residue, thereby obtaining 5.7 g of onium salt SQ-1 (72% yield) as the target substance in the form of an oil.

[0387] MALDI TOF-MS: POSITIVE M+335 (equivalent to C18H11F4S+) Negative M-62 (equivalent to NO3 -)

[0388] [Synthetic Examples 1-2~1-10] Synthesis of Onium Salts SQ-2~SQ-10 Using the corresponding raw materials and known organic synthesis reactions, onium salts SQ-2 to SQ-10 represented by the following formulas were synthesized. [Chemistry 211]

[0389] [2] Synthesis of basic polymers [Synthetic Examples 2-1~2-6] Synthesis of Basic Polymers (P-1~P-6) The monomers were combined using a known formulation and copolymerized in a solvent. The reaction solution was then added to hexane, and the precipitated solid was washed with hexane, separated, and dried to obtain the basic polymers (P-1 to P-6) with the compositions shown below. The composition of the obtained basic polymers was confirmed using 1H-NMR and 13C-NMR, and Mw and Mw / Mn were confirmed using GPC (solvent: THF, standard: polystyrene). [Chemistry 212]

[0390] [3] Preparation of chemically amplified positive inhibitor composition [Examples 1-1 to 1-50, Comparative Examples 1-1 to 1-35] The components were dissolved in an organic solvent according to the compositions shown in Tables 1-3 below. The resulting solutions were filtered through a 5 nm nylon filter and a 1 nm UPE filter to prepare a chemically amplified positive inhibitor composition. The aforementioned organic solvent was a mixture of 940 parts by mass of PGMEA, 1870 parts by mass of EL, and 1870 parts by mass of PGME.

[0391] [Table 1] inhibitor Composition Basic polymers (parts by weight) Quenching agent (parts by weight) Photoacid generator (parts by weight) Polymers containing fluorine atoms Compound (parts by mass) Example 1-1 R-1 P-1(80) SQ-1(7.0) - FP-1(1.5) Examples 1-2 R-2 P-1(80) SQ-1(7.0) - - Examples 1-3 R-3 P-1(80) SQ-2(7.0) - FP-1(1.5) Examples 1-4 R-4 P-1(80) SQ-3(7.0) - FP-1(1.5) Examples 1-5 R-5 P-1(80) SQ-4(7.0) - FP-1(1.5) Examples 1-6 R-6 P-1(80) SQ-5(7.0) - FP-1(1.5) Examples 1-7 R-7 P-1(80) SQ-6(7.0) - FP-1(1.5) Examples 1-8 R-8 P-1(80) SQ-7(7.0) - FP-1(1.5) Examples 1-9 R-9 P-1(80) SQ-8(7.0) - FP-1(1.5) Examples 1-10 R-10 P-1(80) SQ-9(7.0) - FP-1(1.5) Examples 1-11 R-11 P-1(80) SQ-10(7.0) - FP-1(1.5) Examples 1-12 R-12 P-1(80) SQ-1(7.0) - FP-2(1.5) Examples 1-13 R-13 P-1(80) SQ-1(7.0) - FP-3(1.5) Examples 1-14 R-14 P-1(80) SQ-1(7.0) - FP-4(1.5) Examples 1-15 R-15 P-1(80) SQ-1(7.0) - FP-5(1.5) Examples 1-16 R-16 P-1(80) SQ-1(7.0) PAG-1(3) FP-1(1.5) Examples 1-17 R-17 P-1(80) SQ-2(7.0) PAG-2(3) FP-1(1.5) Examples 1-18 R-18 P-1(80) SQ-3(7.0) PAG-3(3) FP-1(1.5) Examples 1-19 R-19 P-1(80) SQ-5(7.0) PAG-4(3) FP-1(1.5) Examples 1-20 R-20 P-1(80) SQ-8(7.0) PAG-5(3) FP-1(1.5) Examples 1-21 R-21 P-1(80) SQ-10(7.0) PAG-6(3) FP-1(1.5) Examples 1-22 R-22 P-2(80) SQ-1(7.0) - FP-1(1.5) Examples 1-23 R-23 P-2(80) SQ-2(7.0) - FP-1(1.5) Examples 1-24 R-24 P-2(80) SQ-3(7.0) - FP-1(1.5) Examples 1-25 R-25 P-2(80) SQ-4(7.0) PAG-1(3) FP-1(1.5) Examples 1-26 R-26 P-2(80) SQ-5(7.0) PAG-2(3) FP-1(1.5) Examples 1-27 R-27 P-2(80) SQ-6(7.0) PAG-3(3) FP-1(1.5) Examples 1-28 R-28 P-2(80) SQ-9(7.0) PAG-5(3) FP-1(1.5) Examples 1-29 R-29 P-2(80) SQ-1(7.0) PAG-6(3) FP-1(1.5)

[0392] [Table 2] inhibitor Composition Basic polymers (parts by weight) Quenching agent (parts by weight) Photoacid generator (parts by weight) Polymers containing fluorine atoms Compound (parts by mass) Examples 1-30 R-30 P-3(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Examples 1-31 R-31 P-3(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Examples 1-32 R-32 P-3(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Examples 1-33 R-33 P-3(80) SQ-4(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Examples 1-34 R-34 P-3(80) SQ-5(7.0) PAG-5(8) PAG-6(4) FP-1(1.5) Examples 1-35 R-35 P-3(80) SQ-9(7.0) PAG-1(12) FP-1(1.5) Examples 1-36 R-36 P-4(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Examples 1-37 R-37 P-4(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Examples 1-38 R-38 P-4(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Examples 1-39 R-39 P-4(80) SQ-7(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Examples 1-40 R-40 P-4(80) SQ-9(7.0) PAG-5(8) PAG-6(4) FP-1(1.5) Examples 1-41 R-41 P-5(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Examples 1-42 R-42 P-5(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Examples 1-43 R-43 P-5(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Examples 1-44 R-44 P-5(80) SQ-5(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Examples 1-45 R-45 P-5(80) SQ-7(7.0) PAG-5(8) PAG-6(4) FP-1(1.5) Examples 1-46 R-46 P-6(80) SQ-1(7.0) PAG-1(8) PAG-6(4) FP-1(1.5) Examples 1-47 R-47 P-6(80) SQ-2(7.0) PAG-2(8) PAG-6(4) FP-1(1.5) Examples 1-48 R-48 P-6(80) SQ-3(7.0) PAG-3(8) PAG-6(4) FP-1(1.5) Examples 1-49 R-49 P-6(80) SQ-4(7.0) PAG-4(8) PAG-6(4) FP-1(1.5) Examples 1-50 R-50 P-6(80) SQ-9(7.0) PAG-5(8) PAG-6(4) FP-1(1.5)

[0393] [Table 3] inhibitor Composition Basic polymers (parts by weight) Quenching agent (parts by weight) Photoacid generator (parts by weight) Polymers containing fluorine atoms Compound (parts by mass) 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)

[0394] 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 213]

[0395] [Chemistry 214]

[0396] [Chemical 215]

[0397] [4] EB Microfilm Review [Examples 2-1 to 2-50, Comparative Examples 2-1 to 2-35] Various chemically amplified positive resist compositions (R-1~R-50, CR-1~CR-35) were spin-coated onto a 152 mm square EUV exposure mask with a chromium compound outermost surface using ACT-M (Tokyo Power Technology Co., Ltd.). The mask was then pre-baked at 110°C for 600 seconds on a heated plate to obtain a resist film with a thickness of 80 nm. The film thickness was measured using an optical measuring instrument, NANOSPEC (Nanometrics Co., Ltd.). Measurements were taken at 81 locations within the plane of the blank substrate, excluding the outer edge portion extending 10 mm inwards, and the average film thickness and thickness range were calculated.

[0398] Then, exposure was performed using an electron beam exposure apparatus (EBM-5000plus manufactured by NuFlare Technology Co., Ltd., with an accelerating voltage of 50kV), PEB was applied at 110°C for 600 seconds, and development was carried out with a 2.38% by mass TMAH aqueous solution to obtain a positive pattern.

[0399] The obtained resist patterns were evaluated as follows. The prepared blank mask with the pattern was observed using an overhead SEM (scanning electron microscope). The optimal exposure (μC / cm²) was set at a 1:1 resolution for the 200nm line-to-spacing (LS) spacing at 1:1, and the smallest size among the 1:1 resolution exposures for the 200nm LS spacing was taken as the resolution (limiting resolution). The LER of the 200nm LS was measured using SEM. The limiting resolution for the isolation spacing (IS) was set at the smallest size among the 9:1 resolution exposures for the 200nm line-to-spacing (LS) spacing at 9:1. Whether the pattern shape was rectangular was determined visually. The results are shown in Tables 4-6.

[0400] [Table 4] inhibitor Composition Optimal Exposure Amount (µC / cm2) L / S resolution (nm) Limit IS solution Resolution (nm) LER (nm) Pattern Shape Example 2-1 R-1 205 28 16 2.7 rectangle Example 2-2 R-2 205 28 16 2.7 rectangle Example 2-3 R-3 200 28 18 2.9 rectangle Examples 2-4 R-4 210 30 16 2.8 rectangle Examples 2-5 R-5 200 28 18 2.7 rectangle Examples 2-6 R-6 200 30 18 2.7 rectangle Examples 2-7 R-7 205 32 18 2.8 rectangle Examples 2-8 R-8 200 28 20 2.8 rectangle Examples 2-9 R-9 205 28 16 2.9 rectangle Example 2-10 R-10 200 30 16 2.6 rectangle Example 2-11 R-11 210 28 18 2.9 rectangle Example 2-12 R-12 200 30 16 2.8 rectangle Example 2-13 R-13 205 32 18 2.7 rectangle Example 2-14 R-14 200 28 16 2.7 rectangle Example 2-15 R-15 205 28 18 2.9 rectangle Example 2-16 R-16 200 30 16 2.8 rectangle Example 2-17 R-17 200 30 16 2.9 rectangle Example 2-18 R-18 205 30 20 2.8 rectangle Example 2-19 R-19 200 28 16 2.8 rectangle Example 2-20 R-20 205 30 18 2.7 rectangle Example 2-21 R-21 200 28 16 2.7 rectangle Example 2-22 R-22 205 30 16 2.8 rectangle Example 2-23 R-23 205 30 18 2.7 rectangle Example 2-24 R-24 205 28 20 2.9 rectangle Example 2-25 R-25 210 28 18 2.9 rectangle Example 2-26 R-26 205 32 18 2.7 rectangle Example 2-27 R-27 205 30 16 2.7 rectangle Example 2-28 R-28 200 28 18 3 rectangle Example 2-29 R-29 205 28 20 2.7 rectangle

[0401] [Table 5] inhibitor Composition Optimal Exposure Amount (µC / cm2) L / S resolution (nm) Limit IS solution Resolution (nm) LER (nm) Pattern Shape Examples 2-30 R-30 205 28 16 2.8 rectangle Example 2-31 R-31 200 30 18 2.9 rectangle Example 2-32 R-32 200 30 16 3 rectangle Example 2-33 R-33 205 38 18 2.7 rectangle Examples 2-34 R-34 200 30 16 2.7 rectangle Example 2-35 R-35 210 30 20 2.8 rectangle Examples 2-36 R-36 205 28 18 2.7 rectangle Example 2-37 R-37 200 28 20 2.8 rectangle Example 2-38 R-38 205 30 18 2.9 rectangle Example 2-39 R-39 205 28 18 3 rectangle Example 2-40 R-40 200 28 16 2.8 rectangle Example 2-41 R-41 205 30 16 2.7 rectangle Example 2-42 R-42 200 30 20 2.7 rectangle Examples 2-43 R-43 205 28 16 2.6 rectangle Example 2-44 R-44 200 30 18 2.7 rectangle Example 2-45 R-45 210 28 18 2.7 rectangle Example 2-46 R-46 205 28 16 2.9 rectangle Example 2-47 R-47 200 30 18 2.7 rectangle Example 2-48 R-48 205 28 20 2.8 rectangle Example 2-49 R-49 210 30 16 2.7 rectangle Example 2-50 R-50 200 28 18 2.8 rectangle

[0402] [Table 6] inhibitor Composition Optimal Exposure Amount (µC / cm2) L / S resolution (nm) Limit IS solution Resolution (nm) LER (nm) Pattern Shape Comparative Example 2-1 CR-1 200 36 twenty two 3.5 rectangle Comparative Example 2-2 CR-2 210 33 twenty one 3.6 Trail Comparative Examples 2-3 CR-3 200 34 twenty two 3.4 round head Comparative Examples 2-4 CR-4 205 33 twenty two 3.8 Trail Comparative Examples 2-5 CR-5 200 33 twenty one 3.6 round head Comparative Examples 2-6 CR-6 210 36 twenty two 3.4 round head Comparative Examples 2-7 CR-7 205 36 twenty three 3.4 rectangle Comparative Examples 2-8 CR-8 200 34 twenty two 3.6 round head Comparative Examples 2-9 CR-9 210 36 twenty two 3.6 round head Comparative Example 2-10 CR-10 205 36 twenty one 3.6 Trail Comparative Example 2-11 CR-11 200 36 twenty two 3.5 rectangle Comparative Example 2-12 CR-12 205 34 twenty three 3.6 Trail Comparative Example 2-13 CR-13 210 36 twenty two 3.6 round head Comparative Example 2-14 CR-14 200 35 twenty two 3.4 round head Comparative Example 2-15 CR-15 210 34 twenty one 3.6 round head Comparative Example 2-16 CR-16 200 38 twenty two 3.5 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 3.6 round head Comparative Example 2-19 CR-19 210 36 twenty three 3.5 Trail Comparative Example 2-20 CR-20 205 33 twenty two 3.4 rectangle Comparative Example 2-21 CR-21 200 36 twenty one 3.6 Trail Comparative Example 2-22 CR-22 210 34 twenty two 3.5 rectangle Comparative Example 2-23 CR-23 200 36 twenty four 3.6 Trail Comparative Example 2-24 CR-24 200 33 twenty two 3.6 rectangle Comparative Example 2-25 CR-25 210 38 twenty one 3.4 round head Comparative Example 2-26 CR-26 210 36 twenty two 3.6 round head Comparative Example 2-27 CR-27 200 36 twenty two 3.6 Trail Comparative Example 2-28 CR-28 205 34 twenty two 3.6 round head Comparative Example 2-29 CR-29 200 38 twenty one 3.5 rectangle Comparative Example 2-30 CR-30 210 33 twenty two 3.6 round head Comparative Example 2-31 CR-31 205 36 twenty two 3.6 Trail Comparative Example 2-32 CR-32 200 34 twenty two 3.5 round head Comparative Example 2-33 CR-33 210 36 twenty three 3.6 rectangle Comparative Example 2-34 CR-34 205 33 twenty two 3.4 round head Comparative Example 2-35 CR-35 200 36 twenty three 3.5 Trail

[0403] The chemically amplified positive resist composition (R-1 to R-50) of the present invention all exhibit good resolution, LER, and pattern rectangularity. On the other hand, the resist composition of the comparative examples (CR-1 to CR-35) did not have sufficient optimization for acid diffusion, and deterioration in resolution, LER, and pattern rectangularity was observed.

[0404] The resist patterning method using the chemically amplified positive resist composition of the present invention is useful in the manufacture of semiconductor devices, especially in the processing of transmissive and reflective blank photomasks.

Claims

1. A chemically amplified positive inhibitor composition comprising: (A) a quencher composed of an onium salt represented by formula (A), (B) a base polymer comprising repeating units represented by formula (B1) and repeating units represented by formula (B9), and a polymer that decomposes and increases the solubility in alkaline developing solutions due to the action of acid, and (C) a photoacid generator; wherein, Xq- is an anion; however, the acid (XqH) with Xq- as the conjugate base has a boiling point of less than 165°C and a molecular weight of less than 150; Z+ is a strontium cation represented by formula (Z-1), a monazine cation represented by formula (Z-2), an ammonium cation represented by formula (Z-3), or a strontium cation represented by formula (Z-4); In the formula, R1 to R9 are halogen atoms or hydrocarbon groups with 1 to 30 carbon atoms that may contain heteroatoms; any two of R1 to R3 may bond to each other and form a ring together with the sulfur atoms they are bonded to; any two of R6 to R9 may bond to each other and form a ring together with the nitrogen atoms they are bonded to. In the formula, m1 is 0 or 1; m2 is 0 or 1; m3 is 0 or 1; m4 is 0, 1, 2, 3 or 4; m5 is 0, 1, 2, 3 or 4; m6 is 0, 1, 2, 3, 4, 5 or 6; m7 is 0, 1, 2, 3, 4, 5 or 6; m8 is 0, 1 or 2; m9 is 0, 1 or 2; m10 is 0, 1 or 2; m11 is 0 or 1; m12 is 0, 1, 2, 3 or 4; m13 is 0, 1 or 2; m14 is 0, 1 or 2; however, m1 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; and m4 + m12 ≧ 1. RF1~RF3 are independently fluorine atoms, fluorinated saturated hydrocarbon groups with 1~6 carbon atoms, fluorinated saturated hydrocarbon oxygen groups with 1~6 carbon atoms, or fluorinated saturated hydrocarbon thio groups with 1~6 carbon atoms, respectively; when m5 is 2 or more, each RF1 can be the same or different from the others; when m6 is 2 or more, each RF2 can be the same or different from the others; when m7 is 2 or more, each RF3 can be the same or different from the others; R10~R13 are halogen atoms other than iodine atoms and fluorine atoms, nitro, cyano, or may contain heteroatoms with 1~20 carbon atoms ...When m8 is 2, the two R10 atoms can be the same or different, and the two R10 atoms can also bond to each other and form a ring together with the carbon atoms they are bonded to. When m9 is 2, the two R11 atoms can be the same or different, and the two R11 atoms can also bond to each other and form a ring together with the carbon atoms they are bonded to. When m10 is 2, the two R12 atoms can be the same or different, and the two R12 atoms can also bond to each other and form a ring together with the carbon atoms they are bonded to. When m13 is 2, the two R13 atoms can be the same or different, and the two R13 atoms can also bond to each other and form a ring together with the carbon atoms they are bonded to. Furthermore, the aromatic rings of S+ directly bonded to the strontium cation can also bond to each other and form a ring together with the S+. LA and LB are independently single bonds, ether bonds, ester bonds, amide bonds, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds, respectively. XL is a single bond, or a hydrocarbon group with 1 to 40 carbon atoms that may contain heteroatoms; 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; R21 is a halogen atom, a nitro group, a carboxyl group, or a saturated hydrocarbon group with 1 to 6 carbon atoms that may be substituted by a halogen atom, or a saturated hydrocarbon carbonyl group with 2 to 8 carbon atoms that may be substituted by a halogen atom; A1 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and a portion of the -CH2- of this saturated hydrocarbon group may also be substituted by -O-. 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 is independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; Z5 is independently a single bond, or may have 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, and the aliphatic alkyl group may also contain a halogen atom, a hydroxyl group, an ether bond, an ester bond or a lactone ring; Z6 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; 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 an alkyl group with 1 to 20 carbon atoms containing heteroatoms; * indicates an atomic bond with a carbon atom in the main chain; *** indicates an atomic bond with Z6; **** indicates an atomic bond with Z7; L1 is a sulfonate bond;Rf7 is a fluorine atom, a fluorinated alkyl group having 1-6 carbon atoms, a fluorinated alkoxy group having 1-6 carbon atoms, or a fluorinated alkyl thio group having 1-6 carbon atoms; R53 is a halogen atom other than fluorine, or may contain a hydrocarbon group having 1-20 carbon atoms and heteroatoms; when h3 is 2, 3, or 4, multiple R53s may also bond to each other and form a ring together with the carbon atoms they are bonded to; A+ is an onium cation.

2. The chemical amplification positive inhibitor composition as claimed in claim 1, wherein, The conjugate acid XqH of the anion Xq- is formic acid, acetic acid, propionic acid, butyric acid, trifluoroacetic acid, 3,3,3-trifluoropropionic acid, trimethylacetic acid, or nitric acid.

3. As in claim 1, the chemical amplification positive inhibitor composition, wherein, The polymer further 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; R31 is a halogen atom, a 1-6 carbon saturated hydrocarbon group that may be substituted by a halogen atom, a 1-6 carbon saturated hydrocarbon oxygen group that may be substituted by a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl oxygen group that may be substituted by 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 by -O-; X is an acid-unstable group when b4 is 1, and a hydrogen atom or an acid-unstable group when b4 is 2 or 3, but at least one is an acid-unstable group.

4. The chemical amplification positive inhibitor composition as described in claim 1, wherein, The polymer further contains 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; R32 and R33 are each independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms, and R32 and R33 may also be bonded to each other and form a ring together with the carbon atoms they are bonded to; R34 are each independently a fluorine atom, a fluorinated alkyl group with 1 to 5 carbon atoms, or a fluorinated alkoxy group with 1 to 5 carbon atoms; R35 are each independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. A3 represents a single bond, an phenyl group, an naphthyl group, 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 alkyl group, or an phenyl or naphthyl group; * indicates an atomic bond with a carbon atom in the main chain.

5. The chemical amplification positive inhibitor composition as claimed in claim 1, wherein, The polymer contains at least one repeating unit selected from the following formula (B3), the following formula (B4), and the following 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; R41 and R42 are independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 6 carbon atoms that may be substituted by a halogen atom, a saturated hydrocarbon oxygen group with 1 to 6 carbon atoms that may be substituted by a halogen atom, or a saturated hydrocarbon carbonyl oxygen group with 2 to 8 carbon atoms that may be substituted by a halogen atom; R43 is a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxy group with 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group with 2 to 20 carbon atoms, a saturated hydrocarbon oxy hydrocarbon 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 f2 can also be a hydroxyl group when it 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 can also be replaced by -O-.

6. The chemical amplification positive inhibitor composition as claimed in claim 1, wherein, The polymer further contains at least one repeating unit selected from the following formula (B6), formula (B7), formula (B8), and formula (B10); wherein g1 and g2 are independently 0, 1, 2, or 3, respectively; RA are independently hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups; Z1 is a single bond or may have a substituent 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, a phenyl 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 is 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, 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 a substituent such as an alkylphenyl group, an alkylnaphthyl group, or *-C(=O)-O-Z51-; Z51 is an aliphatic alkyl group with 1 to 10 carbon atoms, an alkylphenyl group, or an alkylnaphthyl group, and the aliphatic alkyl group may also contain a halogen atom, a hydroxyl group, an ether bond, an ester bond, or a lactone ring; Z6 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; Z7 is independently a single bond, ***-Z71-C(=O)-O-, ***-C(=O)-NH-Z71-, or ***-O-Z71-; Z71 may also contain a heteroatom 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, phenyl substituted with trifluoromethyl, *-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 phenyl substituted with trifluoromethyl, and 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 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, not all of Rf5 and Rf6 can be hydrogen atoms simultaneously.R51 and R52 are each independently a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms; furthermore, R51 and R52 can also bond to each other and form a ring together with the sulfur atoms they are bonded to; M- is a non-nucleophilic relative ion; A+ is an onium cation.

7. The chemical amplification positive inhibitor composition as claimed in claim 1, wherein, Of all the repeating units in the base polymer, the percentage of repeating units with an aromatic ring skeleton is more than 60 mol%.

8. The chemical amplification positive inhibitor composition of claim 1 further contains (D) an organic solvent.

9. The chemical amplification positive inhibitor composition of claim 1 further contains (E) a polymer containing fluorine atoms, which contains at least one repeating unit selected from the following formula (E1), the following formula (E2), the following formula (E3), and the following formula (E4), and may further contain at least one repeating unit selected from the following formula (E5) and the following 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; RB are independently hydrogen atoms, fluorine atoms, methyl groups, or trifluoromethyl groups; RC are independently hydrogen atoms or methyl groups; R101, R102, R104, and R105 are independently hydrogen atoms or saturated hydrocarbon groups having 1 to 10 carbon atoms; R103, R106, R107, and R108 are, independently, hydrogen atoms, hydrocarbon groups with 1 to 15 carbon atoms, fluorinated hydrocarbon groups with 1 to 15 carbon atoms, or acid-unstable groups. When R103, R106, R107, and R108 are hydrocarbon groups or fluorinated hydrocarbon groups, ether bonds or carbonyl groups may be inserted between carbon-carbon bonds. R109 is a hydrogen atom, or a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms containing a heteroatom may be inserted between carbon-carbon bonds. R110 is a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms containing a heteroatom may be inserted between carbon-carbon bonds. R111 is a saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, and part of the -CH2- of the saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. X1 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; X2 is a single bond, *-C(=O)-O- or *-C(=O)-NH-; * is an atomic bond with a carbon atom in the main chain; X3 is a single bond, -O-, *-C(=O)-O-X31-X32- or *-C(=O)-NH-X31-X32-; X31 is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms; X32 is a single bond, ester bond, ether bond or sulfonamide bond; * is an atomic bond with a carbon atom in the main chain.

10. The chemical amplification positive inhibitor composition of claim 1 further contains (A) other quenchers besides the quencher.

11. 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 1 to 10, irradiating the resist film with a pattern using high-energy rays, and developing the irradiated resist film with an alkaline developer.

12. The method for forming a resist pattern as described in claim 11, wherein, The high-energy rays are extreme ultraviolet rays or electron beams with wavelengths of 3 to 15 nm.

13. The method for forming a resist pattern as described in claim 11, wherein, The outermost surface of the substrate is made of a chromium-containing material.

14. The method for forming a resist pattern as described in claim 11, wherein, The substrate is a blank photomask.

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