Chemical amplification positive resist composition and resist pattern forming method

Abstract

The present invention relates to a chemically amplified positive resist composition and a resist pattern forming method. The present invention provides a chemically amplified positive resist composition which is excellent in solvent solubility, high in sensitivity, high in contrast, excellent in lithography properties such as resolution, LER, and the like, and in which development defects are still suppressed and etching resistance is also excellent at the time of fine pattern formation, and a pattern forming method using the same in optical lithography using high-energy rays. A chemically amplified positive resist composition comprising (A) a base polymer containing a polymer which contains a repeating unit represented by the following formula (A1) and whose solubility in an aqueous alkali solution increases due to acid action, and (B) a photo-acid generator composed of an onium salt represented by the following formula (B). In the formula, Z + is an onium cation, Ar AL is an acid-labile group-containing group represented by the following formula (AL), but at least one Ar AL and the carbon atom adjacent to the carbon atom bonded to -SO3 ‑ is bonded.

Description

Technical Field

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

[0002] In recent years, with the increasing integration of integrated circuits, there is a demand for forming finer patterns. The processing of patterns smaller than 0.2 μm mainly uses chemically amplified resist compositions with acid as a catalyst. Exposure sources at this time utilize high-energy rays such as ultraviolet light, far-ultraviolet light, and electron beams (EB). However, especially EB lithography, used in ultra-fine processing technology, has become indispensable as a method for fabricating blank photomasks for semiconductor manufacturing. Such optical lithography uses resist compositions that include positive types that dissolve the exposed area to form a pattern and negative types that leave the exposed area exposed to form a pattern. These are chosen based on the desired resist pattern shape, making them easier for users to select.

[0003] Generally, EB (Edge Electrode) lithography does not use a mask. In positive cases, a method of sequentially irradiating the areas outside the desired resist film with a fine area of ​​EB is employed. In negative cases, the areas where the resist film is to be left are sequentially irradiated. Because it is a scanning operation covering the entire area of ​​the finely divided processing surface, it is more time-consuming than batch exposure using a photomask. To avoid reducing productivity, the resist film must have high sensitivity. Furthermore, due to the long lithography time, the initially lithographically ...

[0004] The sensitivity and pattern profile control of the aforementioned photoresist films have been improved through various modifications, including the selection and combination of materials used in the photoresist composition and processing conditions. One such improvement addresses the issue of acid diffusion, which significantly impacts the resolution of chemically amplified photoresist films. In photomask processing, the desired shape of the photoresist pattern should not change depending on the exposure-to-bake (PEB) time; however, a major reason for this time-dependent change is acid diffusion caused by exposure. This acid diffusion problem is not limited to photomask processing; it also significantly affects sensitivity and resolution in general photoresist compositions, and therefore has been the subject of much research.

[0005] Patent documents 1 and 2 describe examples of suppressing acid diffusion and reducing roughness by increasing the volume of acid generated from the acid-generating agent. However, the suppression of acid diffusion is still not ideal with such acid-generating agents, and there is a desire to develop acid-generating agents with smaller diffusion.

[0006] Furthermore, Patent Document 3 describes an example of controlling acid diffusion by bonding the sulfonic acid generated during exposure to the resin used in the resist composition. This method of suppressing acid diffusion by introducing such repeating units that generate acid during exposure into the base polymer is effective for obtaining patterns with low line edge roughness (LER). However, depending on the structure and introduction rate of these repeating units, there are sometimes cases where the base polymer containing the repeating units that generate acid during exposure exhibits problems with solubility in organic solvents.

[0007] Polymers with a large amount of aromatic backbones with acidic side chains, such as polyhydroxystyrene, have historically been used as resist compositions for KrF lithography. However, due to their large absorption of light near 200 nm, they cannot be used as resist compositions for ArF lithography. Nevertheless, resist compositions for EB lithography and extreme ultraviolet (EUV) lithography, which are powerful techniques for forming patterns with smaller processing limits than ArF lithography, are important materials for achieving high etch resistance.

[0008] The base polymers used in positive EB lithography and EUV lithography resist compositions primarily employ acid-insensitive groups (acid-decomposing protecting groups) that deprotect the acidic functional groups of the phenol side chains on the base polymer by using acid generated from a photoacid generator through high-energy radiation as a catalyst. These groups are soluble in alkaline developing solutions. The aforementioned acid-insensitive groups mainly include tert-alkyl, tert-butoxycarbonyl, and acetal groups. Using protecting groups with relatively low activation energy, such as acetal groups, for deprotection can yield highly sensitive resist films. However, if the diffusion of the generated acid is not sufficiently suppressed, even the unexposed areas of the resist film may undergo deprotection, leading to LER degradation and a decrease in dimensional uniformity of pattern linewidth (CDU).

[0009] Furthermore, when using a sulfonate salt containing an acid with a low pKa and high acid strength, such as the fluorinated alkyl sulfonic acid described in Patent Document 4, and a repeating unit containing an acetal group, there is a problem of forming patterns with a large LER. That is, for the deprotection of the acetal group, which has a relatively low activation energy for deprotection, the acid strength of the fluorinated alkyl sulfonic acid is too high. Therefore, even if the diffusion of the acid is suppressed, the deprotection reaction will still occur due to the trace amount of acid that has diffused into the unexposed area.

[0010] Furthermore, Patent Documents 5 and 6 propose photoacid generators that produce non-fluorinated aromatic sulfonic acids with multiple large alkyl substituents, while Patent Document 7 proposes a photoacid generator with a triarylbenzenesulfonic acid anionic structure. Patent Document 8 proposes a photoacid generator that produces non-fluorinated aromatic sulfonic acids with an iodine-containing aromatic ring. Patent Document 9 proposes a photoacid generator that produces aromatic sulfonic acids with an unstable tertiary ester-type acid group. By increasing the molecular weight of the generated acid through multiple alkyl substituents, aromatic rings, and iodine atoms, acid diffusion is reduced. However, when forming fine patterns, the suppression of acid diffusion is still insufficient, leaving room for further improvement.

[0011] With the recent trend towards miniaturization of resist patterns, the formation of fine, isolated patterns has become particularly important. To improve the dissolution contrast between the exposed and unexposed areas, structural modifications have been made to the acid-labile groups of the base polymer. Patent Document 10 describes a structure in which the hydroxyl groups of polyhydroxystyrene are protected with tertiary ethers and acetals, and fluorine atoms are further introduced into the adjacent positions. Patent Document 11 describes a structure in which the hydroxyl and carboxyl groups of vinyl salicylic acid are protected with cyclic acetals. These designs all aim to improve the dissolution rate of the polymer after the deprotection reaction of the acid-labile groups in the exposed area, and have been confirmed to offer some degree of performance improvement.

[0012] Existing technical documents

[0013] Patent documents

[0014] [Patent Document 1] Japanese Patent Application Publication No. 2009-053518

[0015] [Patent Document 2] Japanese Patent Application Publication No. 2010-100604

[0016] [Patent Document 3] Japanese Patent Application Publication No. 2011-22564

[0017] [Patent Document 4] Japanese Patent No. 5083528

[0018] [Patent Document 5] Japanese Patent No. 6248882

[0019] [Patent Document 6] Japanese Patent No. 7067271

[0020] [Patent Document 7] Japanese Patent No. 7032549

[0021] [Patent Document 8] Japanese Patent Application Publication No. 2023-177038

[0022] [Patent Document 9] Japanese Patent No. 7531671

[0023] [Patent Document 10] Japanese Patent Application Publication No. 2025-000201

[0024] [Patent Document 11] International Publication No. 2023 / 162837 Summary of the Invention

[0025] (The problem the invention aims to solve)

[0026] In recent years, there has been a demand for resist compositions that not only have excellent line-to-spacing (LS), isolated lines (IL), and isolated spacing (IS), but also excellent hole pattern shapes. Patent Document 5 describes an acid generator that produces acid in a large volume and inhibits acid diffusion, which can produce patterns with good resolution and roughness, but it has the problem of corner rounding in hole patterns.

[0027] In view of the foregoing, the present invention aims to provide a chemically amplified positive resist composition, particularly suitable for optical lithography using high-energy rays such as KrF excimer lasers, ArF excimer lasers, electron beams (EB), and EUV, which exhibits excellent solvent solubility, high sensitivity, high contrast, high resolution, excellent lithography performance such as LER, and suppresses development defects and exhibits excellent etching resistance during the formation of fine patterns. The invention also provides a pattern formation method using the chemically amplified resist composition.

[0028] (Methods for solving problems)

[0029] In order to achieve the aforementioned objectives, the inventors of this application have made efforts in research and have discovered polymers containing repeating units with cyclic acetal structures having aromatic ring condensation, and photoacid generators that produce arene sulfonic acid derivatives, and which have 2, 3, or 4 -SO3 groups. - The bonded aromatic ring contains an aryl group with an ether-type acid unstable group, and at least one aryl group with an ether-type acid unstable group and -SO3. - When an onium salt with a structure in which adjacent carbon atoms are bonded is introduced into a resist composition as a photoacid generator, the acid generated from it has a moderate acidity, and excessive diffusion of the acid is suppressed. As a result, a resist pattern with good resolution, low LER, and suppressed development defects can be obtained. Furthermore, due to its moderate solubility inhibition, a resist pattern with good rectangularity is obtained, thus achieving the present invention.

[0030] That is, the present invention provides the following chemically amplified positive resist composition and resist patterning method.

[0031] 1. A chemically amplified positive resist composition comprising (A) a base polymer, a polymer containing repeating units represented by formula (A1) and exhibiting increased solubility in alkaline aqueous solutions due to acid action, and (B) a photoacid generator consisting of an onium salt represented by formula (B).

[0032] [Chemistry 1]

[0033]

[0034] In the formula, a1 is 0 or 1, and a2 is 0, 1, 2 or 3 when a1 is 0, and 0, 1, 2, 3, 4 or 5 when a1 is 1.

[0035] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0036] X 1 It is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-, where * indicates an atomic bond with a carbon atom in the main chain.

[0037] X 2 A group obtained by means of a single bond, an aliphatic alkylene group, a carbonyl group, a sulfonyl group, or a combination thereof, having 1 to 4 carbon atoms.

[0038] X 3 and X 4 Each can be independently an oxygen atom or a sulfur atom, but X 2 and X 4 Bonded to adjacent carbon atoms of the aromatic ring,

[0039] R 1 and R 2 Each is an independent hydrocarbon group consisting of hydrogen atoms, or may contain heteroatoms, and has 1 to 20 carbon atoms. Also, R 1 and R 2 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0040] R 3 It can be a halogen atom, hydroxyl group, cyano group, nitro group, pentafluorothio group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxygen group with 2 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms or -N(R) group. 3A (R) 3B ), R 3A and R 3B Each is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; when a2 is 2 or more, each R 3 They can be the same or different, multiple Rs 3 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0041] [Chemistry 2]

[0042]

[0043] In the formula, n1 is 0 or 1, n2 is 0, 1, 2, 3 or 4, and n3 is 2, 3 or 4. However, when n1 is 0, 2 ≤ n2 + n3 ≤ 5, and when n1 is 1, 2 ≤ n2 + n3 ≤ 7.

[0044] R 101 The radical can be a halogen atom, nitro, cyano, hydroxyl, carboxyl, or a hydrocarbon group with 1-20 carbon atoms containing heteroatoms; it can also be a hydrocarbon oxy group with 1-20 carbon atoms containing heteroatoms; it can also be a hydrocarbon thio group with 1-20 carbon atoms containing heteroatoms; or it can be a hydrocarbon oxycarbonyl group with 1-20 carbon atoms containing heteroatoms. When n2 is 2, 3, or 4, each R... 101 They can be the same or different, multiple Rs 101 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0045] Z + It is a ium cation.

[0046] Ar AL The group represented by the formula (AL) contains an acid-labile group, but at least one Ar. AL and -SO3 - The bonded carbon atoms are adjacent carbon atoms.

[0047] [Chemistry 3]

[0048]

[0049] In the formula, n4 is 0 or 1, n5 is 0, 1, 2, 3 or 4, n6 is 0, 1, 2, 3 or 4, and n7 is 1 or 2. However, when n4 is 0, the formula is 1 ≤ n5 + n6 + n7 ≤ 5, and when n4 is 1, the formula is 1 ≤ n5 + n6 + n7 ≤ 7.

[0050] R 102 The radical can be a halogen atom other than fluorine, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon oxy group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms; or it can be a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms containing heteroatoms. When n5 is 2, 3, or 4, each R... 102 They can be the same or different, multiple Rs 102 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0051] R F When n6 is 2, 3, or 4, each R... F They can be the same or different.

[0052] R L1and R L2 Each is an independent hydrocarbon group having 1 to 12 carbon atoms, R L3 R is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. L1 R L2 and R L3 The -CH2- group of the hydrocarbon group may also be partially replaced by -O- or -S-. When the hydrocarbon group contains an aromatic ring or multiple bonds, part or all of the hydrogen atoms bonded to the carbon atoms constituting the aromatic ring or multiple bonds may also be replaced by halogen atoms, cyano groups, nitro groups, alkyl groups with 1 to 4 carbon atoms that may contain halogen atoms, or alkoxy groups with 1 to 4 carbon atoms that may contain halogen atoms. Furthermore, R... L1 and R L2 They can also bond to each other and form a ring together with the carbon atoms they are bonded to. A portion of the -CH2- in this ring can be replaced by -O- or -S-, but R... L3 When the alicyclic structure, aromatic ring, and multiple bonds are all absent, R L1 and R L2 They bond to each other and together with the carbon atoms they are bonded to form a ring. Part of the -CH2- in this ring can also be replaced by -O- or -S-.

[0053] * indicates an atomic bond.

[0054] 2. As in 1., a chemically amplified positive resist composition, wherein X 3 and X 4 All are oxygen atoms.

[0055] 3. Chemically amplified positive resist compositions as in 1. or 2, wherein X 2 It is a carbonyl group.

[0056] 4. A chemically amplified positive resist composition as described in any of 1.~3, wherein the photoacid generator is represented by the following formula (B1).

[0057] [Chemistry 4]

[0058]

[0059] In the formula, n1, n2, n3, n5, n6, n7, R 101 R 102 R F R L1 ~R L3 and Z + As mentioned above.

[0060] 5. A chemically amplified positive resist composition as described in 4, wherein the photoacid generator is represented by the following formula (B2).

[0061] [Chemistry 5]

[0062]

[0063] In the formula, n2, n3, n5, n6, n7, R 101 R 102 R F R L1 ~R L3 and Z + As mentioned above.

[0064] 6. A chemically amplified positive resist composition as described in any of 1.~5, wherein Z + The sulfonium cation is represented by formula (Z-1) or the monazine cation is represented by formula (Z-2).

[0065] [Chemistry 6]

[0066]

[0067] In the formula, R ct1 ~R ct5 Each is an independent halogen atom, or may contain heteroatoms, of a hydrocarbon group having 1 to 30 carbon atoms; also, R ct1 and R ct2 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[0068] 7. A chemically amplified positive resist composition as described in any of 1.~5, wherein Z + The sulfonium cation is represented by the following formula (Z-3).

[0069] [Chemistry 7]

[0070]

[0071] 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, but m1 is... When m1 is 1, it is 0 ≤ m6 + m9 ≤ 4; when m2 is 0, it is 0 ≤ m6 + m9 ≤ 6; when m2 is 0, it is 0 ≤ m7 + m10 ≤ 4; when m2 is 1, it is 0 ≤ m7 + m10 ≤ 6; when m3 is 0, it is 1 ≤ m4 + m5 + m8 + m14 ≤ 4; when m3 is 1, it is 1 ≤ m4 + m5 + m8 + m14 ≤ 6; when m11 is 0, it is 0 ≤ m12 + m13 ≤ 4; when m11 is 1, it is 0 ≤ m12 + m13 ≤ 6; and m4 + m12 ≥ 1.

[0072] RF1 ~R F3 Each of the following is independently a fluorine atom, a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon oxygen group having 1 to 6 carbon atoms, or a fluorinated saturated hydrocarbon thio group having 1 to 6 carbon atoms. When m5 is 2, 3, or 4, each R F1 They can be the same or different. When m6 is 2, 3, 4, 5 or 6, each R... F2 They can be the same or different. When m7 is 2, 3, 4, 5 or 6, each R... F3 They can be the same or different.

[0073] R ct6 ~R ct9 The radical can be a halogen atom other than iodine and fluorine, a nitro group, a cyano group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. When m8 is 2, there are 2 R radicals. ct6 They can be the same or different, 2 Rs ct6 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m9 is 2, there are 2 R atoms. ct7 They can be the same or different, 2 Rs ct7 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m10 is 2, the two R atoms... ct8 They can be the same or different, 2 Rs ct8 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m13 is 2, there are 2 R atoms. ct9 They can be the same or different, 2 Rs ct9 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0074] Furthermore, the sum of S in sulfonium cations + Directly bonded aromatic rings can also bond to each other and with S + Together they form a ring.

[0075] L A and L B Each bond can be independently a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0076] X L It can be a single bond, or it can also contain a heteroatom with 1 to 40 carbon atoms and a hydrocarbon group.

[0077] 8. A chemically amplified positive resist composition as described in any one of 1. to 7, wherein the polymer further contains a repeating unit represented by the following formula (A2).

[0078] [Chemistry 8]

[0079]

[0080] In the formula, b1 is 0, 1, or 2; b2 is 1, 2, or 3; and b3 is an integer satisfying 0 ≤ b3 ≤ 5 + 2(b1) - b2.

[0081] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0082] Y 1 It is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-, where * indicates an atomic bond with a carbon atom in the main chain.

[0083] R 11 It can be a halogen atom, a nitro group, a carboxyl group, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom.

[0084] A 1 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

[0085] 9. A chemically amplified positive resist composition as described in any one of 1. to 8, wherein the polymer contains at least one repeating unit selected from the following formula (A3), the following formula (A4), and the following formula (A5).

[0086] [Chemistry 9]

[0087]

[0088] In the formula, c is 0, 1, 2, 3, 4, 5, or 6; d is 0, 1, 2, 3, or 4; e1 is 0 or 1; e2 is 0, 1, or 2; and e3 is 0, 1, 2, 3, 4, or 5.

[0089] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0090] R 21 and R 22 Each can be independently a hydroxyl group, a halogen atom, a 1-8 carbon saturated hydrocarbon group that can be substituted with a halogen atom, a 1-8 carbon saturated hydrocarbon oxygen group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom.

[0091] R 23It 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 group with 2 to 20 carbon atoms, a saturated hydrocarbon sulfide group with 2 to 20 carbon atoms, a halogen atom, a nitro group, or a cyano group. When e3 is 1 or 2, it can also be a hydroxyl group.

[0092] A 2 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

[0093] 10. A chemically amplified positive resist composition as described in any one of 1. to 9, wherein the polymer further comprises at least one repeating unit selected from the repeating units represented by formula (A6-1) and formula (A6-2).

[0094] [Chemistry 10]

[0095]

[0096] In the formula, f1 is 0 or 1, f2 is 0, 1 or 2, f3 is an integer satisfying 0 ≤ f3 ≤ 5 + 2(f2) - f4, f4 is 1, 2 or 3, and f5 is 0 or 1.

[0097] f11 is 0, 1, or 2; f12 is 0, 1, or 2; f13 is 0, 1, or 2; f14 is 0, 1, 2, 3, 4, or 5.

[0098] R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0099] A 3 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of this saturated hydrocarbon group may also be replaced by -O-.

[0100] A 4 It is a single bond, phenylene, naphthylene, or *-C(=O)-OA 41 -, A 41 It may also contain an aliphatic alkylene group, or a phenylene or naphthylene group, with 1 to 20 carbon atoms, and may also contain a hydroxyl group, ether bond, ester bond, or lactone ring. * indicates an atomic bond with a carbon atom in the main chain.

[0101] R 31 It can be a halogen atom, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom.

[0102] R 32 and R 33 Each can be independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms.32 and R 33 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0103] R 34 Each is independently a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkoxy group having 1 to 5 carbon atoms.

[0104] R 35 Each can independently be a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms.

[0105] When X is 1 in f4, it is an acid-labile group; when X is 2 or 3 in f4, it is a hydrogen atom or an acid-labile group, but at least one of them is an acid-labile group.

[0106] 11. A chemically amplified positive resist composition as described in any one of 1. to 10, wherein the polymer contains at least one repeating unit selected from the following formula (A7), the following formula (A8), the following formula (A9), the following formula (A10), and the following formula (A11).

[0107] [Chemistry 11]

[0108]

[0109] In the formula, g1 and g2 are each independently 0, 1, 2, or 3; h1 is 0 or 1; h2 is 0, 1, 2, 3, or 4; and 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.

[0110] R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0111] Z 1 It can be a single bond or may have substituents, phenylene

[0112] Z 2 For single bonds, **-C(=O)-OZ 21 -、**-C(=O)-N(H)-Z 21 -or**-OZ 21 -, Z 21 It is a divalent group obtained by aliphatic hydrocarbon groups, phenylene groups, or combinations thereof having 1 to 6 carbon atoms, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups.

[0113] Z 3 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, amide bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds.

[0114] Z4 It is a divalent group obtained by a single bond, or an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, or a combination thereof, and may also contain a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0115] Z 5 Each can be a single bond, or a phenylene group with substituents, or a naphthylene group with substituents, *-C(=O)-OZ 51 -or *-C(=O)-N(R)-Z 51 -, Z 51 It is an aliphatic hydrocarbon group, phenylene, or naphthylene with 1 to 10 carbon atoms. This aliphatic hydrocarbon group may also contain a halogen atom, hydroxyl group, ether bond, ester bond, or lactone ring. R is a hydrogen atom, or it may also be a hydrocarbon group with 1 to 10 carbon atoms containing heteroatoms.

[0116] Z 6 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, amide bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds.

[0117] Z 7 Each is independently a single bond, ***-Z 71 -C(=O)-O-、***-C(=O)-N(R)-Z 71 -or ***-OZ 71 -, Z 71 It can also contain a hydrocarbon group with 1 to 20 carbon atoms, R as described above.

[0118] Z 8 Each is independently a single key, ****-Z 81 -C(=O)-O-、****-C(=O)-N(R)-Z 81 -or ****-OZ 81 -, Z 81 It can also contain a hydrocarbon group with 1 to 20 carbon atoms, R as described above.

[0119] Z 9 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, trifluoromethyl-substituted phenylene, *-C(=O)-OZ 91 -、*-C(=O)-N(R)-Z 91 -or *-OZ 91 -, Z 91 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or trifluoromethyl-substituted phenylene, having 1 to 6 carbon atoms. It may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group, R as described above.

[0120] * indicates an atomic bond with a carbon atom in the main chain, ** indicates an atomic bond with a Z atom. 1 atomic bonds, *** represents the bond between Z and Z6 atomic bonds, **** represents the bond between Z and 7 atomic bonds,

[0121] L 1 The bonds can be single bonds, ether bonds, ester bonds, carbonyl groups, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds.

[0122] Rf 1 and Rf 2 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms.

[0123] Rf 3 and Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms.

[0124] Rf 5 and Rf 6 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, but all Rf 5 and Rf 6 They are not both hydrogen atoms.

[0125] Rf 7 When h2 is 2, 3, or 4, each Rf is a fluorine atom, a fluorinated alkyl group having 1 to 6 carbon atoms, a fluorinated alkoxy group having 1 to 6 carbon atoms, a fluorinated alkyl thio group having 1 to 6 carbon atoms, or a pentafluorothio group. 7 They can be the same or different.

[0126] R 41 and R 42 Each can independently be a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. Also, R 41 and R 42 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[0127] R 43 When h3 is 2, 3, or 4, each R... 43 They can be the same or different, multiple Rs 43 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0128] M - It is a non-nucleophilic relative ion.

[0129] A + It is a ium cation.

[0130] 12. A chemically amplified positive resist composition as described in any one of 1. to 11, wherein the content of repeating units having an aromatic ring skeleton in all repeating units of the base polymer is 60 mol% or more.

[0131] 13. A chemically amplified positive resist composition as described in any of 1. to 12, further comprising (C) an organic solvent.

[0132] 14. A chemically amplified positive resist composition, such as any one of 1. to 13, further comprises (D) a quencher.

[0133] 15. The chemically amplified positive resist composition of any one of 1. to 14, further comprising a polymer containing fluorine atoms, the polymer containing fluorine atoms containing at least one repeating unit selected from the repeating units represented by formula (E1), formula (E2), formula (E3), and formula (E4), and may also further contain at least one repeating unit selected from the repeating units represented by formula (E5) and formula (E6).

[0134] [Chemistry 12]

[0135]

[0136] 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; and k is 1, 2, or 3.

[0137] R B Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0138] R C Each can be independently a hydrogen atom or a methyl group.

[0139] R 301 R 302 R 304 and R 305 Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms.

[0140] R 303 R 306 R 307 and R 308 Each is independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-labile group, R 303 R 306 R 307 and R 308 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group may also be inserted between the carbon-carbon bonds.

[0141] R309 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, consisting of hydrogen atoms or groups containing heteroatoms inserted between carbon-carbon bonds; when j1 is 2 or 3, each R 309 They can be the same or different.

[0142] R 310 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which heteroatoms may be inserted between carbon-carbon bonds; when j2 is 2 or more, each R 310 They can be the same or different.

[0143] R 311 A saturated hydrocarbon group with 1 to 20 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom. A portion of the -CH2- group of this saturated hydrocarbon group may also be replaced by an ester or ether bond.

[0144] W 1 It is a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms or a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms.

[0145] W 2 These are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-, where * represents an atomic bond with a carbon atom in the main chain.

[0146] W 3 For single bonds, -O-, *-C(=O)-OW 31 -W 32 -or *-C(=O)-N(H)-W 31 -W 32 -, W 31 W is a single bond or a saturated alkylene group with 1 to 10 carbon atoms. 32 It is a single bond, ester bond, ether bond, or sulfonamide bond, and * is an atomic bond with a carbon atom in the main chain.

[0147] 16. A chemically amplified positive resist composition as described in any of 1. to 15, further comprising a photoacid generator other than an onium salt represented by formula (B).

[0148] 17. A method for forming a resist pattern, comprising the following steps:

[0149] A resist film is formed on a substrate using a chemically amplified positive resist composition as described in any of 1 to 16. A pattern is then irradiated onto the resist film using high-energy radiation.

[0150] The resist film of the irradiated pattern was developed using an alkaline developer.

[0151] 18. The method for forming a resist pattern as described in 17, wherein the high-energy ray is extreme ultraviolet light or an electron beam with a wavelength of 3 to 15 nm.

[0152] 19. A method for forming a resist pattern as described in 17 or 18, wherein the outermost surface of the substrate is composed of a chromium-containing material.

[0153] 20. A method for forming a resist pattern as described in any one of 17 to 19, wherein the substrate is a blank photomask.

[0154] (The effect of the invention)

[0155] Chemically amplified positive resist compositions that incorporate onium salts represented by formula (B) as photoacid generators exhibit extremely high resolution in microfabrication techniques, particularly EB and EUV lithography, and can provide patterns with low LER and suppressed development defects. Furthermore, the onium salts represented by formula (B) possess moderate solubility inhibition properties, thus providing patterns with good rectangularity, making them suitable materials for chemically amplified positive resist compositions. Detailed Implementation

[0156] The present invention will now be described in detail. Furthermore, in the following description, depending on the structure represented by the chemical formula, there may be asymmetric carbon and possibly mirror-image isomers and non-mirror-image isomers. In such cases, these isomers will be represented by a single formula. These isomers may be used individually or in mixtures of two or more.

[0157] [Chemical amplification positive resist composition]

[0158] [(A) Basic Polymer]

[0159] The chemically amplified positive resist composition of the present invention comprises, as component (A), a base polymer containing a polymer whose solubility in alkaline developer is increased due to acid action.

[0160] The aforementioned polymer contains repeating units represented by the following formula (A1) (hereinafter also referred to as repeating unit a1).

[0161] [Chemistry 13]

[0162]

[0163] In formula (A1), a1 is 0 or 1. When a1 is 0, it is a benzene ring; when a1 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with a1 of 0 is preferred. a2 is 0, 1, 2, or 3 when a1 is 0, and 0, 1, 2, 3, 4, or 5 when a1 is 1. Considering the availability of raw materials, a2 of 0, 1, 2, or 3 is preferred, with 0, 1, or 2 being even better.

[0164] In equation (A1), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R AHydrogen atoms or methyl groups are preferred, with hydrogen atoms being even better.

[0165] In formula (A1), X 1 The bonds are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-. * indicates an atomic bond with a carbon atom in the main chain. Among these, single bonds and *-C(=O)-O- are preferred, with single bonds being the most ideal.

[0166] In formula (A1), X 2 The group can be a single bond, an aliphatic alkylene group with 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a combination thereof. Among these, considering the raw materials, a single bond, a carbonyl group, or a sulfonyl group is preferred; considering the polar group formed after the reaction, a single bond or a carbonyl group is even better.

[0167] In formula (A1), X 3 and X 4 Each can be an oxygen atom or a sulfur atom independently. But X 2 and X 4 Bonded to adjacent carbon atoms in the aromatic ring. X 3 and X 4 They can be the same or different, taking into account the perspective of reactivity, X 3 and X 4 Both are better if they contain oxygen atoms.

[0168] In equation (A1), R 1 and R 2Each hydrocarbon group consists of 1 to 20 carbon atoms, and may also contain heteroatoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, decadecyl, heptadecyl, octadecyl, nonadecanyl, and icosyl; 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 and naphthyl; aralkyl groups with 7 to 20 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0169] Also, R 1 and R 2 They can also bond with each other and form rings together with the carbon atoms they are bonded to. Specific examples of rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, and adamantane rings. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0170] In equation (A1), R 3 It can be a halogen atom, hydroxyl group, cyano group, nitro group, pentafluorothio group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxygen group with 2 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms or -N(R) group. 3A (R) 3B R 3A and R 3BEach group is independently composed of a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. The aforementioned halogen atom is preferably a fluorine, chlorine, bromine, or iodine atom, with fluorine or iodine being more preferred. The hydrocarbon group, hydroxyl group, hydroxyl carbonyl group, and thiol group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given and discussed in relation to R. 1 and R 2 The alkyl group represented is an example of the same. Furthermore, some or all of the hydrogen atoms in the aforementioned alkyl group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, a portion of the -CH2- group in the aforementioned alkyl group can be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonate ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. When a2 is 2 or more, each R... 3 They can be the same or different.

[0171] Furthermore, when a2 is 2 or more, multiple R 3 They can also bond with each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. Specific examples of rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, and adamantane rings. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0172] Specific examples of repeated unit A1 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned earlier, Me is methyl. Furthermore, the bonding positions of various substituents on the aromatic ring can also be interchanged.

[0173] [Chemistry 14]

[0174]

[0175] [Chemistry 15]

[0176]

[0177] [Chemistry 16]

[0178]

[0179] [Chemistry 17]

[0180]

[0181] [Chemistry 18]

[0182]

[0183] [Chemistry 19]

[0184]

[0185] [Chemistry 20]

[0186]

[0187] [Chemistry 21]

[0188]

[0189] [Chemistry 22]

[0190]

[0191] [Chemistry 23]

[0192]

[0193] [Chemistry 24]

[0194]

[0195] [Chemistry 25]

[0196]

[0197] [Chemistry 26]

[0198]

[0199] [Chemistry 27]

[0200]

[0201] [Chemistry 28]

[0202]

[0203] [Chemistry 29]

[0204]

[0205] [Chemistry 30]

[0206]

[0207] [Chemistry 31]

[0208]

[0209] [Chemistry 32]

[0210]

[0211] [Chemistry 33]

[0212]

[0213] [Chemistry 34]

[0214]

[0215] [Chemistry 35]

[0216]

[0217] [Chemistry 36]

[0218]

[0219] [Chemistry 37]

[0220]

[0221] [Chemistry 38]

[0222]

[0223] [Chemistry 39]

[0224]

[0225] [Chemistry 40]

[0226]

[0227] [Chemistry 41]

[0228]

[0229] [Chemistry 42]

[0230]

[0231] [Chemistry 43]

[0232]

[0233] [Chemistry 44]

[0234]

[0235] [Chemistry 45]

[0236]

[0237] [Chemistry 46]

[0238]

[0239] [Chemistry 47]

[0240]

[0241] [Chemistry 48]

[0242]

[0243] [Chemistry 49]

[0244]

[0245] [Transformation 50]

[0246]

[0247] [Chemistry 51]

[0248]

[0249] [Chemistry 52]

[0250]

[0251] [Chemistry 53]

[0252]

[0253] [Chemistry 54]

[0254]

[0255] [Chemistry 55]

[0256]

[0257] [Chemistry 56]

[0258]

[0259] [Chemistry 57]

[0260]

[0261] [Chem.58]

[0262]

[0263] [Chemistry 59]

[0264]

[0265] [Transformation 60]

[0266]

[0267] [Chemistry 61]

[0268]

[0269] [Chemistry 62]

[0270]

[0271] [Chemistry 63]

[0272]

[0273] In the chemically amplified resist composition of the present invention, the structural feature of the base polymer (A) can be exemplified by the presence of repeating unit A1 containing a cyclic acetal structure with an aromatic ring condensation ring. The cyclic acetal structure with the aromatic ring condensation ring exhibits good solvent solubility and also acts as an acid-indestructible group, thus undergoing a deprotection reaction under acid action to generate two polar groups. This improves the contrast between the exposed and unexposed areas. Furthermore, the generated two polar groups bond with adjacent carbon atoms, allowing hydroxyl or carboxyl groups to form hydrogen bonds. This suppresses swelling caused by the alkaline developer during alkaline development, inhibiting the collapse of the resist pattern in the unexposed areas. The cyclic acetal structure with the aromatic ring condensation ring remaining in the unexposed areas, being a bicyclic structure, still exhibits high resistance during the etching process. Before exposure, the polymer contains a cyclic acetal structure with high solvent solubility, which inhibits precipitation in the solvent. After exposure, when developed with an alkaline developer, the polar groups generated after the acetal structure is deprotected have a high affinity for the alkaline developer, thus effectively removing the exposed part and reducing the risk of development defects.

[0274] Of all the repeating units in the aforementioned polymer, the content of repeating unit A1 is ideally 5-50 mol%, more preferably 10-45 mol%, and even more preferably 15-40 mol%. Repeating unit A1 can be used alone or in combination of two or more types.

[0275] The aforementioned polymer may also contain repeating units represented by the following formula (A2) (hereinafter also referred to as repeating unit a2).

[0276] [Chemistry 64]

[0277]

[0278] In formula (A2), b1 is 0, 1, or 2; 0 represents the benzene skeleton, 1 represents the naphthalene skeleton, and 2 represents the anthracene skeleton. b2 is 1, 2, or 3. b3 is an integer satisfying 0 ≤ b3 ≤ 5 + 2(b1) - b2. When b1 is 0, it is preferable that b2 is 0, 1, 2, or 3, and b3 is 1, 2, or 3. When b1 is 1 or 2, it is preferable that b2 is 0, 1, 2, 3, or 4, and b3 is 1, 2, or 3.

[0279] In equation (A2), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0280] In formula (A2), Y 1 It represents a single bond, *-C(=O)-O-, or *-C(=O)-N(H)-. * indicates an atomic bond with a carbon atom in the main chain.

[0281] In equation (A2), R 11 The carbon group can be a halogen atom, nitro group, carboxyl group, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, a 1-6 carbon saturated hydrocarbon oxygen group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl oxygen group that can be substituted with a halogen atom. The saturated hydrocarbon group, saturated hydrocarbon oxygen group, and saturated hydrocarbon carbonyl oxygen group can be linear, branched, or cyclic. Specific examples include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; and groups obtained by combining them. If the number of carbon atoms is below the upper limit, the solubility in alkaline developing solutions is good. When b3 is 2 or more, each R... 11 They can be the same or different.

[0282] In formula (A2), A 1 The saturated alkylene group is a single bond or a saturated alkylene group with 1 to 10 carbon atoms, and a portion of the -CH2- group may be replaced by -O-. The aforementioned saturated alkylene group can be linear, branched, or cyclic, and specific examples include alkyl dimethyl groups with 1 to 10 carbon atoms such as methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane-1,6-diyl, and their structural isomers; cyclic saturated alkylene groups with 3 to 10 carbon atoms such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining these groups. When the aforementioned saturated alkylene group contains an ether bond, Y in formula (A2) 1 When it is *-C(=O)-O- or *-C(=O)-N(H)-, it can be inserted anywhere except between the carbon atom at the α-position and the carbon atom at the β-position relative to -O- or -N(H)-. Also, Y 1When it is a single bond, the atom bonded to the main chain becomes an ether oxygen atom. A second ether bond can also be inserted at any position other than between the carbon atom at the α-position and the carbon atom at the β-position relative to this ether oxygen atom. Furthermore, 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.

[0283] Y 1 and A 1 When all bonds are single bonds, the aromatic ring and the polymer backbone are directly bonded (i.e., there are no connecting groups (-Y)). 1 -A 1 When repeating unit A2, ideal examples can be found 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 to these. Furthermore, in the following formula, R... A As mentioned above.

[0284] [Chemistry 65]

[0285]

[0286] [Chemistry 66]

[0287]

[0288] [Chemistry 67]

[0289]

[0290] Y 1 It is *-C(=O)-O- or *-C(=O)-N(H)- (that is, it has Y) 1 -A 1 When R is used as a linking group, ideal examples of repeating unit A2 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above.

[0291] [Chemistry 68]

[0292]

[0293] [Chemistry 69]

[0294]

[0295] [Chemistry 70]

[0296]

[0297] [Chemistry 71]

[0298]

[0299] [Chemistry 72]

[0300]

[0301] When the aforementioned polymer contains repeating unit A2, its content is ideally 30-95 mol% of all repeating units constituting the aforementioned polymer, and more ideally 35-85 mol%. However, when the polymer described later contains at least one of the repeating units represented by formula (A3), formula (A4), and formula (A5) that provide higher etch resistance, and this unit has a phenolic hydroxyl group as a substituent, this ratio is also preferred within the aforementioned range. Repeating unit A2 can be used alone or in combination of two or more.

[0302] The aforementioned polymer may also contain at least one repeating unit selected from the following formula (A3) (hereinafter also referred to as repeating unit A3), the following formula (A4) (hereinafter also referred to as repeating unit A4), and the following formula (A5) (hereinafter also referred to as repeating unit A5).

[0303] [Chemistry 73]

[0304]

[0305] In equations (A3) and (A4), c is 0, 1, 2, 3, 4, 5, or 6. d is 0, 1, 2, 3, or 4.

[0306] In equations (A3) and (A4), R 21 and R 22 Each of the following is independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group with 1 to 8 carbon atoms that may be substituted with a halogen atom, a saturated hydroxyl group with 1 to 8 carbon atoms that may be substituted with a halogen atom, or a saturated carbonyl group with 2 to 8 carbon atoms that may be substituted with a halogen atom. The aforementioned saturated hydrocarbon group, saturated hydroxyl group, and saturated carbonyl group can be linear, branched, or cyclic. When c is 2, 3, 4, 5, or 6, each R... 21 They can be the same or different. When d is 2, 3, or 4, each R... 22 They can be the same or different.

[0307] In formula (A5), e1 is 0 or 1. e2 is 0, 1 or 2. When e2 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. e3 is 0, 1, 2, 3, 4 or 5. When e2 is 0, e3 is preferably 0, 1, 2 or 3; when e2 is 1 or 2, e3 is preferably 0, 1, 2, 3 or 4.

[0308] In equation (A5), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0309] In equation (A5), R23 The group can be a saturated hydrocarbon group (1-20 carbon atoms), a saturated hydrocarbon oxygen group (1-20 carbon atoms), a saturated hydrocarbon carbonyl group (2-20 carbon atoms), a saturated hydrocarbon oxy group (2-20 carbon atoms), a saturated hydrocarbon thio group (2-20 carbon atoms), a halogen atom, a nitro group, or a cyano group. When e3 is 1 or 2, it can also be a hydroxyl group. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxygen group, saturated hydrocarbon carbonyl group, saturated hydrocarbon oxygen group, and saturated hydrocarbon thio group can be linear, branched, or cyclic. When e3 is 2, 3, 4, or 5, each R... 23 They can be the same or different.

[0310] In formula (A5), A 2 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group may also be replaced by -O-. The aforementioned saturated hydrocarbon group can be linear, branched, or cyclic, and specific examples can be given in A in formula (A2). 1 The examples shown in the description are the same.

[0311] When at least one of the repeating units A3 to A5 is used as a constituent unit of the aforementioned polymer, in addition to the etching resistance of the aromatic ring, the main chain has a ring structure, resulting in improved etching resistance and EB irradiation resistance during pattern inspection.

[0312] When the aforementioned polymer contains repeating units A3 to A5, it is preferable that their content be 5 mol% or more of all repeating units in the polymer to achieve the effect of improving etching resistance. Furthermore, it is preferable that the content of repeating units A3 to A5 be 25 mol% or less of all repeating units constituting the aforementioned polymer, and more preferably 20 mol% or less. Ideally, if the amount introduced when there are no functional groups or when the functional group is other than hydroxyl groups is 25 mol% or less, there is no risk of developing defects. Repeating units A3 to A5 can be used alone or in combination of two or more.

[0313] If the aforementioned polymer contains repeating unit A1, repeating unit A2, and at least one repeating unit selected from A3 to A5, it is preferable to have both high etch resistance and high resolution. In this case, it is preferable that these repeating units account for 60 mol% or more of all repeating units in the aforementioned polymer, more preferably 70 mol% or more, even more preferably 80 mol% or more, and ideally more than 90 mol% or more.

[0314] The aforementioned polymer may also contain at least one repeating unit selected from the repeating units represented by formula (A6-1) and formula (A6-2).

[0315] [Chemistry 74]

[0316]

[0317] In formula (A6-1), f1 is 0 or 1. f2 is 0, 1, or 2; 0 indicates a benzene skeleton, 1 indicates naphthalene, and 2 indicates anthracene. f3 is an integer satisfying 0 ≤ f3 ≤ 5 + 2(f2) - f4. f4 is 1, 2, or 3. f5 is 0 or 1. When f2 is 0, it is preferable that f3 is 0, 1, 2, or 3, and f4 is 1, 2, or 3. When f2 is 1 or 2, it is preferable that f3 is 0, 1, 2, 3, or 4, and f4 is 1, 2, or 3.

[0318] In equation (A6-2), f11 is 0, 1, or 2. f12 is 0, 1, or 2. f13 is 0, 1, or 2. f14 is 0, 1, 2, 3, 4, or 5.

[0319] In equations (A6-1) and (A6-2), R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0320] In formula (A6-1), A 3 The saturated alkylene group is a single bond or a saturated alkylene group with 1 to 10 carbon atoms, and a portion of the -CH2- group may be replaced by -O-. The aforementioned saturated alkylene group can be linear, branched, or cyclic, and specific examples include alkyl diyl groups with 1 to 10 carbon atoms such as methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers; cyclic saturated alkylene groups with 3 to 10 carbon atoms such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining these groups. When the aforementioned saturated alkylene group contains an ether bond, and f1 in formula (A6-1) is 1, it can be inserted anywhere except between the carbon atom at the α-position and the carbon atom at the β-position relative to the ester oxygen atom. Furthermore, when f1 is 0, the atom bonded to the main chain is an ether oxygen atom, and a second ether bond can be inserted at any position other than between the carbon atom at the α-position and the carbon atom at the β-position relative to this ether oxygen atom. Also, 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.

[0321] In formula (A6-2), A 4 It is a single bond, phenylene, naphthylene, or *-C(=O)-OA 41 -. A 41 It may also contain an aliphatic alkylene group with 1 to 20 carbon atoms, or a phenylene or naphthylene group, which may also contain a hydroxyl group, ether bond, ester bond, or lactone ring. * indicates an atomic bond with the carbon atom of the main chain.

[0322] In equation (A6-1), R 31The saturated hydrocarbon group having 1 to 6 carbon atoms, which may be substituted with halogen atoms, or the saturated hydrocarbon carbonyl group having 1 to 6 carbon atoms, which may be substituted with halogen atoms, or the saturated hydrocarbon carbonyl group having 2 to 8 carbon atoms, which may be substituted with halogen atoms. The saturated hydrocarbon group, saturated hydrocarbon carbonyl group, and saturated hydrocarbon carbonyl group can be linear, branched, or cyclic. Specific examples include alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups having 3 to 6 carbon atoms 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 f3 is 2 or higher, each R... 31 They can be the same or different.

[0323] In equation (A6-2), R 32 and R 33 Each can be independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. 32 and R 33 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0324] In equation (A6-2), R 34 Each is independently a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkoxy group having 1 to 5 carbon atoms. When f13 is 2, each R 34 They can be the same or different.

[0325] In equation (A6-2), R 35 Each can be an independent hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. When f14 is 2, 3, 4, or 5, each R 35 They can be the same or different.

[0326] In formula (A6-1), when f4 is 1, X is an acid-indestructible group. When f4 is 2 or 3, X is either a hydrogen atom or an acid-indestructible group independently, but at least one is an acid-indestructible group. That is, the repeating unit A6-1 is either a phenolic hydroxyl group bonded to an aromatic ring that is protected by an acid-indestructible group, or a carboxyl group bonded to an aromatic ring that is protected by an acid-indestructible group. The aforementioned acid-indestructible groups can be used without special limitation as long as they are acidic groups provided by acid desorption in various known chemically amplified positive resist compositions.

[0327] The aforementioned acid-labile groups, such as tertiary saturated hydrocarbon groups, are preferred for use as monomers in polymerization obtained by distillation, as they typically have 4 to 18 carbon atoms.

[0328] It is preferable that the saturated hydrocarbon groups bonded to the tertiary carbon atoms of the aforementioned tertiary saturated hydrocarbon groups have 1 to 15 carbon atoms. These saturated hydrocarbon groups with 1 to 15 carbon atoms can be linear, branched, or cyclic, and may contain oxygen-containing functional groups such as ether bonds or carbonyl groups between their carbon-carbon bonds. 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 to which they are bonded.

[0329] Specific examples of groups bonded to the aforementioned tertiary carbon atoms include methyl, ethyl, propyl, adamantyl, norbornel, tetrahydrofuran-2-yl, 7-oxanorborne-2-yl, cyclopentyl, 2-tetrahydrofuranyl, tricyclic [5.2.1.0] 2,6 ] Decyl, 8-ethyl-8-tricyclo[5.2.1.0 2,6 Decyl, 3-methyl-3-tetracyclo[4.4.0.1] 2,5 .1 7,10 [12 bases, 4 rings [4.4.0.1]] 2 ,5 .1 7,10 Dodecayl, 3-oxo-1-cyclohexyl, etc.

[0330] Examples of the aforementioned tertiary saturated hydrocarbon groups include tert-butyl, tert-pentyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1,2-trimethylpropyl, 1-adamantyl-1-methylethyl, 1-methyl-1-(2-norborneol)ethyl, 1-methyl-1-(tetrahydrofuran-2-yl)ethyl, 1-methyl-1-(7-oxanorborneol-2-yl)ethyl, 1-methylcyclopentyl, and 1-ethyl Cyclopentyl, 1-propylcyclopentyl, 1-cyclopentylcyclopentyl, 1-cyclohexylcyclopentyl, 1-(2-tetrahydrofuranyl)cyclopentyl, 1-(7-oxanorbornen-2-yl)cyclopentyl, 1-methylcyclohexyl, 1-ethylcyclohexyl, 1-cyclopentylcyclohexyl, 1-cyclohexylcyclohexyl, 2-methyl-2-norbornenyl, 2-ethyl-2-norbornenyl, 8-methyl-8-tricyclo[5.2.1.0] 2,6 ] Decyl, 8-ethyl-8-tricyclo[5.2.1.0 2,6 Decyl, 3-methyl-3-tetracyclo[4.4.0.1] 2,5 .1 7,10 Dodecayl, 3-ethyl-3-tetracyclo[4.4.0.1] 2, 5 .1 7,10 Dodecyl, 2-methyl-2-adamantyl, 2-ethyl-2-adamantyl, 1-methyl-3-oxo-1-cyclohexyl, 1-methyl-1-(tetrahydrofuran-2-yl)ethyl, 5-hydroxy-2-methyl-2-adamantyl, 5-hydroxy-2-ethyl-2-adamantyl, but not limited to these.

[0331] Furthermore, examples of the aforementioned acid-indestructible groups include those represented by formula (A6-1-1). The group represented by formula (A6-1-1) is frequently used as an acid-indestructible group and is a useful option for providing a relatively rectangular pattern at the interface between the pattern and the substrate. When X is a group represented by formula (A6-1-1), an acetal structure is formed.

[0332] [Chemistry 75]

[0333]

[0334] In the formula, chain lines represent atomic bonds.

[0335] In formula (A6-1-1), R L11 It consists of a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. The aforementioned saturated hydrocarbon group can be linear, branched, or cyclic.

[0336] R L11 The appropriate group can be selected based on the design requirements regarding the sensitivity of the group to acid decomposition. For example, if a design is to ensure relatively high stability and decompose in strong acids, it is preferable that the hydrogen atom or the carbon atom bonded to the acetal carbon be a tertiary carbon group. Utilizing the R group formed by the tertiary carbon atom and the acetal carbon bond... L11 Examples include tert-butyl, tert-pentyl, and 1-adamantyl, but these are not the only possibilities. For designs requiring high reactivity and high sensitivity to pH changes, straight-chain alkyl groups are preferred. The choice also depends on the combination of the acid generator and quencher incorporated with the resist composition, but when R... L12 When selecting a saturated hydrocarbon group with a relatively large terminal end, and designing the solution to cause a large change in solubility due to decomposition, then R... L11 In general, it is preferable that the carbon atom bonded to the acetal carbon be a secondary carbon atom. Utilizing the R-type bond between the secondary carbon atom and the acetal carbon... L11 Examples include isopropyl, sec-butyl, cyclopentyl, cyclohexyl, etc., but are not limited to these.

[0337] In formula (A6-1-1), R L12 The hydrocarbon group has 1 to 30 carbon atoms. This hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. A portion of the -CH2- group can be replaced by heteroatoms such as oxygen or sulfur atoms, resulting in ether bonds or thioether bonds. Specific examples of the aforementioned hydrocarbon group include saturated hydrocarbon groups with 1 to 30 carbon atoms and aryl groups with 6 to 30 carbon atoms. Especially in the formation of fine patterns, to obtain higher resolution, R... L12 Hydrocarbon groups with 1 to 6 carbon atoms are preferred. R L12 When the hydrocarbon group has 1 to 6 carbon atoms, the alcohol generated after the acid deprotection reaction is water-soluble. Therefore, when a positive pattern is formed with an alkaline developer, it will dissolve in the developer, which can suppress residue defects in the exposed part.

[0338] Ideal examples of groups represented by formula (A6-1-1) can be listed below, but are not limited to these. Also, in the following formula, R... L11 As mentioned earlier, chain lines represent atomic bonds.

[0339] [Chemistry 76]

[0340]

[0341] [Chemistry 77]

[0342]

[0343] [Chemistry 78]

[0344]

[0345] Ideal examples of repeating unit A6-2 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above.

[0346] [Chemistry 79]

[0347]

[0348] [Chemistry 80]

[0349]

[0350] As an unstable group in other acids, the hydrogen atom of the phenolic hydroxyl group can also be replaced by -CH2COO- (tertiary saturated hydrocarbon group). In this case, the aforementioned tertiary saturated hydrocarbon group can be the same tertiary saturated hydrocarbon group used for the protection of the aforementioned phenolic hydroxyl group.

[0351] When the aforementioned polymer contains at least one repeating unit selected from A6-1 and A6-2, its content is preferably 5-30 mol% of all repeating units in the aforementioned polymer. Ideally, the combined content of repeating units A1, A3-1, and A3-2 in all repeating units of the aforementioned polymer is 10-60 mol%, more preferably 10-50 mol%, and even more preferably 10-40 mol%. Repeating units A6-1 and A6-2 can be used alone or in combination of two or more.

[0352] The aforementioned polymer may also contain at least one repeating unit selected from the following formula (A7) (hereinafter also referred to as repeating unit A7), the following formula (A8) (hereinafter also referred to as repeating unit A8), the following formula (A9) (hereinafter also referred to as repeating unit A9), the following formula (A10) (hereinafter also referred to as repeating unit A10), and the following formula (A11) (hereinafter also referred to as repeating unit A11).

[0353] [Chemistry 81]

[0354]

[0355] In equations (A7) to (A11), R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 It is a single bond or may have substituents. Z 2 For single bonds, **-C(=O)-OZ 21 -、**-C(=O)-N(H)

[0356] -Z 21 -or**-OZ 21 -. Z 21 It is a divalent group obtained by aliphatic hydrocarbon groups, phenylene groups, or combinations thereof having 1 to 6 carbon atoms, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups. 3 It can be a single bond, ether bond, ester bond, sulfonate bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. 4 It is a single bond, or a divalent group obtained by aliphatic hydrocarbon groups, phenylene groups, or combinations thereof with 1 to 6 carbon atoms, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups. 5 Each can be a single bond, or a phenylene group with substituents, or a naphthylene group with substituents, *-C(=O)-OZ 51 -or *-C(=O)-N(R)-Z 51 -. Z 51 R is an aliphatic hydrocarbon group, phenylene, or naphthylene, having 1 to 10 carbon atoms. This aliphatic hydrocarbon group may also contain a halogen atom, hydroxyl group, ether bond, ester bond, or lactone ring. R is a hydrogen atom, or may be a hydrocarbon group with 1 to 10 carbon atoms containing heteroatoms. Z 6 It can be a single bond, ether bond, ester bond, sulfonate bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. 7 Each is independently a single bond, ***-Z 71 -C(=O)-O-、***-C(=O)-N(R)-Z 71 -or ***-OZ 71 -. Z 71 It can also contain a hydrocarbon group with 1 to 20 carbon atoms and a heteroatom. R is as described above. Z 8 Each is independently a single key, ****-Z 81 -C(=O)-O-、****-C(=O)-N(R)-Z 81 -or ****-OZ 81 -. Z 81It can also contain a hydrocarbon group with 1 to 20 carbon atoms and a heteroatom. R is as described above. Z 9 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, trifluoromethyl-substituted phenylene, *-C(=O)-OZ 91 -、*-C(=O)-N(R)-Z 91 -or *-OZ 91 -. Z 91 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or trifluoromethyl-substituted phenylene, having 1 to 6 carbon atoms. It may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group. R is as described above. * indicates an atomic bond with a carbon atom in the main chain. ** indicates a bond with Z. 1 The atomic bonds. *** indicates the relationship between Z and 6 Atomic bonds. **** represents the bond between Z and Z. 7 Atomic bonds.

[0357] Z 21 Z 51 and Z 91 The aliphatic alkyl sub-groups can be linear, branched, or cyclic. Specific examples include alkyl diyl groups such as methane-diyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, 1,1-dimethylethane-1,2-diyl, pentane-1,5-diyl, 2-methylbutane-1,2-diyl, and hexane-1,6-diyl; cycloalkyl diyl groups such as cyclopropane-diyl, cyclobutane-diyl, cyclopentane-diyl, and cyclohexane-diyl; and groups obtained by combining them.

[0358] Z 71 and Z 81 The subhydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples are listed below, but are not limited to these.

[0359] [Chemistry 82]

[0360]

[0361] In the formula, the dashed lines represent atomic bonds.

[0362] In equation (A7), R 41 and R 42Each group can be an independent hydrocarbon group with 1 to 20 carbon atoms, and may also contain heteroatoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 20 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 20 carbon atoms such as cyclohexenyl; aryl groups with 6 to 20 carbon atoms such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 20 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them, with aryl groups being preferred. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may also contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0363] Also, R 41 and R 42 They can also bond to each other and form rings together with the sulfur atoms they are bonded to. Specific examples of the aforementioned rings can be shown in the following formulas, etc.

[0364] [Chemistry 83]

[0365]

[0366] In the formula, the dashed line represents Z. 4 Atomic bonds.

[0367] Specific examples of cations in repeating unit A7 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above.

[0368] [Chemistry 84]

[0369]

[0370] [Chemistry 85]

[0371]

[0372] [Chemistry 86]

[0373]

[0374] [Chemistry 87]

[0375]

[0376] [Chemistry 88]

[0377]

[0378] [Chemistry 89]

[0379]

[0380] [Chemistry 90]

[0381]

[0382] [Chemistry 91]

[0383]

[0384] [Chemistry 92]

[0385]

[0386] [Chemistry 93]

[0387]

[0388] In equation (A7), M - These are non-nucleophilic relative ions. Preferred non-nucleophilic relative ions are halide ions, sulfonic acid anions, imide acid anions, and methylated acid anions. Specific examples of halide ions include chloride ions and bromide ions. Specific examples of 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. Specific examples of imide acid anions (imide ions) include bis(trifluoromethylsulfonyl)imide ions, bis(perfluoroethylsulfonyl)imide ions, and bis(perfluorobutylsulfonyl)imide ions. Specific examples of the aforementioned methylated acid anions (methylated ions) include tris(trifluoromethylsulfonyl) methylated ions and tris(perfluoroethylsulfonyl) methylated ions.

[0389] Other examples of the aforementioned non-nucleophilic relative ions can be exemplified by anions represented by any of the following formulas (A7-1) to (A7-4).

[0390] [Chemistry 94]

[0391]

[0392] In equation (A7-1), R fa It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain fluorine atoms or heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given by R in the following formula (A7-1-1). fa1 The alkyl group represented is an example of the same. Furthermore, some or all of the hydrogen atoms in the aforementioned alkyl group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned alkyl group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentatone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0393] The anion represented by formula (A7-1) is preferably represented by the following formula (A7-1-1).

[0394] [Chemistry 95]

[0395]

[0396] In equation (A7-1-1), Q 1 and Q 2 Each atom is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; however, to improve solvent solubility, at least one atom is preferably trifluoromethyl. m can be 0, 1, 2, 3, or 4, with 1 being particularly preferred. R fa1 Hydrocarbon groups with 1 to 40 carbon atoms that can also contain heteroatoms are preferred. Ideal heteroatoms include oxygen, nitrogen, sulfur, and halogen atoms, with oxygen atoms being even more desirable. From the viewpoint of achieving high resolution during the formation of fine patterns, hydrocarbon groups with 6 to 30 carbon atoms are particularly advantageous.

[0397] In formula (A7-1-1), R fa1The hydrocarbon groups representing 1 to 40 carbon atoms 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, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecanyl, and icosyl; and cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norbornel, norbornelmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl. Hydrocarbon groups; unsaturated aliphatic hydrocarbon groups with 2 to 40 carbons such as 2-propenyl and 3-cyclohexenyl; aryl groups with 6 to 40 carbons such as phenyl, 1-naphthyl, 2-naphthyl, and 9-fluorenyl; aralkyl groups with 7 to 40 carbons such as benzyl and diphenylmethyl; polycyclic hydrocarbon groups containing aromatic rings with 7 to 40 carbons such as 9,10-ethbridged-9,10-dihydroanthrayl and 6,13-ethbridged-6,13-dihydropentaphenyl; hydrocarbon groups with 17 to 40 carbons having a steroid skeleton; and groups obtained by combining them.

[0398] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, a portion of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain hydroxyl, fluorine, chlorine, bromine, iodine, cyano, nitro, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. Specific examples of hydrocarbon groups containing heteroatoms include tetrahydrofuranyl, methoxymethyl, ethoxymethyl, methylthiomethyl, acetamidemethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetoxymethyl, 2-carboxy-1-cyclohexyl, 2-oxopropyl, 4-oxo-1-adamantyl, 3-oxocyclohexyl, etc.

[0399] In formula (A7-1-1), L a1 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, or carbamate bonds. From a synthetic point of view, ether bonds or ester bonds are preferred, with ester bonds being more ideal.

[0400] Specific examples of anions represented by equation (A7-1) are listed below, but are not limited to these. Furthermore, in the following equation, Q... 1 As mentioned above, Ac represents the acetyl group.

[0401] [Chemistry 96]

[0402]

[0403] [Chemistry 97]

[0404]

[0405] [Chem. 98]

[0406]

[0407] [Chemistry 99]

[0408]

[0409] [Chemistry 100]

[0410]

[0411] [Chemistry 101]

[0412]

[0413] [Chemistry 102]

[0414]

[0415] [Chemistry 103]

[0416]

[0417] [Chemistry 104]

[0418]

[0419] [Chemistry 105]

[0420]

[0421] [Chemistry 106]

[0422]

[0423] [Chemistry 107]

[0424]

[0425] In equation (A7-2), R fb1 and R fb2 Each group consists of a fluorine atom or may contain heteroatoms and has 1 to 40 carbon atoms. These hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given by R in formula (A7-1-1). fa1 The hydrocarbon group represented is an example of the same. R fb1 and R fb2 Preferably, it is a straight-chain fluorinated alkyl group having fluorine atoms or 1 to 4 carbon atoms. Also, R fb1 and R fb2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-N).- -SO2-CF2-) together form a ring, in which case R fb1 and R fb2 The groups obtained by mutual bonding are preferably fluorinated ethylidene or fluorinated propylene.

[0426] In equation (A7-3), R fc1 R fc2 and R fc3 Each group consists of a fluorine atom or may contain heteroatoms and has 1 to 40 carbon atoms. These hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given by R in formula (A7-1-1). fa1 The hydrocarbon group represented is an example of the same. R fc1 R fc2 and R fc3 Preferably, it is a straight-chain fluorinated alkyl group having fluorine atoms or 1 to 4 carbon atoms. Also, R fc1 and R fc2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-C). - -SO2-CF2-) together form a ring, in which case R fc1 and R fc2 The groups obtained by mutual bonding are preferably fluorinated ethylidene or fluorinated propylene.

[0427] In equation (A7-4), R fd It can also be a hydrocarbon group with 1 to 40 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 by R in formula (A7-1-1). fa1 The alkyl group represented is an example of the same. Furthermore, some or all of the hydrogen atoms in the aforementioned alkyl group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned alkyl group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentatone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0428] Specific examples of anions represented by formula (A7-4) are listed below, but are not limited to these.

[0429] [Chemistry 108]

[0430]

[0431] [Chemistry 109]

[0432]

[0433] 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 (A7-5).

[0434] [Chemical 110]

[0435]

[0436] In equation (A7-5), 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 being 1, 2, or 3 is ideal, with 2 or 3 being even more ideal. z being 0, 1, or 2 is preferable.

[0437] In formula (A7-5), X BI It is an iodine atom or a bromine atom. When x and / or y are 2 or more, each X BI They can be the same or different.

[0438] In formula (A7-5), L 11 It can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond, carbamate bond, or a saturated hydrocarbon group with 1 to 6 carbon atoms. Part of the -CH2- of the hydrocarbon group may also be replaced by an ether bond or ester bond. The aforementioned saturated hydrocarbon group can be linear, branched, or cyclic.

[0439] In formula (A7-5), L 12 When x is 1, it is a single bond or may contain a heteroatom of 1 to 20 carbon atoms, and when x is 2 or 3, it may contain a heteroatom of 1 to 20 carbon atoms, or a (x+1) valence hydrocarbon group.

[0440] L 12 The alkylene groups representing 1 to 20 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl diyl groups with 1 to 20 carbon atoms, such as methane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl; cyclopentane diyl, cyclohexane diyl, norcamphene diyl, adamantane diyl, and tricyclic [5.2.1.0] 2,6[Cyclic saturated hydrocarbon groups with 3-20 carbon atoms, such as decanediyl; unsaturated aliphatic hydrocarbon groups with 2-20 carbon atoms, such as vinylene and propene-1,3-diyl; aryl groups with 6-20 carbon atoms, such as phenylene, naphthylene, and anthracenediyl; polycyclic hydrocarbon groups containing aromatic rings with 7-20 carbon atoms, such as 9,10-ethbridged-9,10-dihydroanthracenediyl and 6,13-ethbridged-6,13-dihydropentaphenyl; and groups obtained by combining them, etc.] 12 The (x+1) valence hydrocarbon group representing 1 to 20 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be obtained by removing one or two hydrogen atoms from the aforementioned examples of hydrocarbon groups representing 1 to 20 carbon atoms.

[0441] Furthermore, some or all of the hydrogen atoms of the aforementioned alkylene group and (x+1) valence hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group of the aforementioned alkylene group and (x+1) valence hydrocarbon group can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may also 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, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0442] In formula (A7-5), L 13 It can be a single bond, ether bond, ester bond, sulfonate bond, carbonate bond or carbamate bond.

[0443] In formula (A7-5), R fe It can be a hydroxyl group, carboxyl group, fluorine atom, chlorine atom, bromine atom, amino group, hydrocarbon group with 1 to 20 carbon atoms, hydrocarbon oxygen group with 1 to 20 carbon atoms, hydrocarbon thioyl group with 1 to 20 carbon atoms, hydrocarbon carbonyl group with 2 to 20 carbon atoms, hydrocarbon carbonyl group with 2 to 20 carbon atoms, or hydrocarbon sulfonyl group with 1 to 20 carbon atoms, -N(R feA (R) feB ), -N(R feC )-C(=O)-R feD or -N(R) feC )-C(=O)-OR feD The hydrocarbon group, hydrocarbon oxy group, hydrocarbon thio group, hydrocarbon carbonyl group, hydrocarbon oxycarbonyl group, hydrocarbon carbonyloxy group, and hydrocarbon sulfonyloxy group may also contain at least one selected from fluorine atom, chlorine atom, bromine atom, iodine atom, hydroxyl group, amino group, ester bond, and ether bond. feA and R feB Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R feCIt 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 oxygen group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms. R feD It can be an aliphatic hydrocarbon group with 1-16 carbon atoms, an aryl group with 6-12 carbon atoms, or an aralkyl group with 7-15 carbon atoms. It may also contain a halogen atom, a hydroxyl group, a saturated alkyloxy group with 1-6 carbon atoms, a saturated alkylcarbonyl group with 2-6 carbon atoms, or a saturated alkylcarbonyloxy group with 2-6 carbon atoms. The aforementioned aliphatic hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. The aforementioned hydrocarbon group, alkyloxy group, alkylcarbonyl group, alkyloxycarbonyl group, alkylcarbonyloxy group, and alkylsulfonyloxy group can be any of linear, branched, or cyclic. When x and / or z are 2 or more, each R... fe They can be the same or different.

[0444] Among these, R fe Hydroxyl group, -N(R) feC )-C(=O)-R feD -N(R) feC )-C(=O)-OR feD Fluorine atoms, chlorine atoms, bromine atoms, methyl groups, and methoxy groups are preferred.

[0445] In equation (A7-5), Rf 11 ~Rf 14 Each can be independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these must be a fluorine atom or a trifluoromethyl group. Also, Rf 11 With Rf 12 They can also combine to form carbonyl groups. Especially Rf 13 and Rf 14 Both are preferred if they contain fluorine atoms.

[0446] Specific examples of anions represented by equation (A7-5) are listed below, but are not limited to these. Furthermore, in the following equation, X... BI As mentioned above.

[0447] [Chemistry 111]

[0448]

[0449] [Chemistry 112]

[0450]

[0451] [Chemistry 113]

[0452]

[0453] [Chemistry 114]

[0454]

[0455] [Chemistry 115]

[0456]

[0457] [Chemistry 116]

[0458]

[0459] [Chemistry 117]

[0460]

[0461] [Chemistry 118]

[0462]

[0463] [Chemistry 119]

[0464]

[0465] [Chemistry 120]

[0466]

[0467] [Chemistry 121]

[0468]

[0469] [Chemistry 122]

[0470]

[0471] [Chemistry 123]

[0472]

[0473] [Chemistry 124]

[0474]

[0475] [Chemistry 125]

[0476]

[0477] [Chemistry 126]

[0478]

[0479] [Chemistry 127]

[0480]

[0481] [Chemistry 128]

[0482]

[0483] [Chemistry 129]

[0484]

[0485] [Chemistry 130]

[0486]

[0487] [Chemistry 131]

[0488]

[0489] [Chemistry 132]

[0490]

[0491] [Chemistry 133]

[0492]

[0493] [Chemistry 134]

[0494]

[0495] M -Other examples of anions represented include paragraphs

[0076] and

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

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

[0253] to

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

[0044] to

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

[0205] to

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

[0170] to

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

[0026] to

[0028] of Japanese Patent Application Publication No. 2024-62406, and Japanese Patent Application Publication No. 2 Paragraphs

[0022] to

[0025] of Japanese Patent Application Publication No. 024-62407,

[0026] to

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

[0028] to

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

[0026] to

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

[0028] to

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

[0028] to

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

[0031] to

[0033] of Japanese Patent Application Publication No. 2024-72280, and

[0034] of Japanese Patent Application Publication No. 2024-72281. Paragraphs

[0023] ~

[0025] , paragraphs

[0026] ~

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

[0020] ~

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

[0140] ~

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

[0023] ~

[0025] of Japanese Patent Application Publication No. 2024-83304, paragraphs

[0028] ~

[0031] of Japanese Patent Application Publication No. 2024-99500, paragraphs

[0030] ~

[0033] of Japanese Patent Application Publication No. 2024-99502, paragraphs

[0028] ~

[0029] of Japanese Patent Application Publication No. 2024-99502.

[030] , Paragraphs from Japanese Patent Application Publication No. 2024-101557

[0030] ~

[0032] , Paragraphs from Japanese Patent Application Publication No. 2024-102842

[0025] ~

[0027] , Paragraphs from Japanese Patent Application Publication No. 2024-102843

[0033] ~

[0035] , Paragraphs from Japanese Patent Application Publication No. 2024-127832

[0021] ~

[0022] , Paragraphs from Japanese Patent Application Publication No. 2024-144354

[0169] ~

[0172] , Paragraphs from Japanese Patent Application Publication No. 2024-144356

[0178] ~

[0181] , Paragraphs from Japanese Patent Application Publication No. 2024-160436

[0040] ~

[0143] ,The authors of paragraphs

[0157] to

[0158] of Japanese Patent No. 7247732, paragraphs

[0227] to

[0238] of Japanese Patent No. 7446352, paragraphs

[0253] to

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

[0309] to

[0312] of Japanese Patent No. 7466782, etc.

[0496] The aforementioned non-nucleophilic relative ions may also include the fluorobenzenesulfonic acid anion bonded to an aromatic group containing an iodine atom as described in Japanese Patent No. 6648726, the anion with an acid decomposition mechanism as described in International Publication No. 2021 / 200056 and Japanese Patent Application Publication No. 2021-70692, the anion with a cyclic ether group as described in Japanese Patent Application Publication No. 2018-180525 and Japanese Patent Application Publication No. 2021-35935, and the anion as described in Japanese Patent Application Publication No. 2018-92159.

[0497] The aforementioned non-nucleophilic relative ions may further include the anions of high-volume benzenesulfonic acid derivatives without fluorine atoms as described in Japanese Patent Application Publication Nos. 2006-276759, 2015-117200, 2016-65016, 2019-202974, and 2024-104830; the benzenesulfonic acid anions without fluorine atoms bonded to aromatic groups containing iodine atoms as described in Japanese Patent No. 6645464; and the alkylsulfonic acid anions. Furthermore, the anions described in paragraphs

[0229] to

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

[0033] to

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

[0498] The aforementioned non-nucleophilic relative ions may further include the anions of disulfonic acid as described in Japanese Patent Application Publication No. 2015-206932, the anions of sulfonamides and sulfonamides as described in International Publication No. 2020 / 158366, which are sulfonic acid on one side and different from sulfonamides or sulfonamides on the other side, and the anions of sulfonic acid and carboxylic acid as described in Japanese Patent Application Publication No. 2015-24989.

[0499] In equations (A8) and (A9), g1 and g2 are each independently 0, 1, 2 or 3, with 1 being preferred.

[0500] In equation (A10), 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.

[0501] In equations (A8), (A9) and (A10), L1 The bonds can be single bonds, ether bonds, ester bonds, carbonyl groups, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Among these, from a synthetic perspective, ether bonds, ester bonds, and carbonyl groups are more ideal, with ester bonds and carbonyl groups being even more desirable.

[0502] In equation (A8), Rf 1 and Rf 2 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among these, as Rf 1 and Rf 2 To increase the acid strength, fluorine atoms are preferred. Rf 3 and Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Among these, Rf is used to improve solvent solubility. 3 and Rf 4 At least one of them is preferably trifluoromethyl.

[0503] In equation (A9), Rf 5 and Rf 6 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. However, all Rf... 5 and Rf 6 They are not all hydrogen atoms at the same time. Among these, in order to improve solvent solubility, Rf... 5 and Rf 6 At least one of them is preferably trifluoromethyl.

[0504] In formula (A10), Rf 7 It is a fluorine atom, a fluorinated alkyl group having 1 to 6 carbon atoms, a fluorinated alkoxy group having 1 to 6 carbon atoms, a fluorinated alkyl thio group having 1 to 6 carbon atoms, or a pentafluorothio group. Rf 7 The most desirable components are fluorine atom, trifluoromethyl, difluoromethyl, trifluoromethoxy, difluoromethoxy, trifluoromethylthio, or difluoromethylthio, with fluorine atom, trifluoromethyl, or trifluoromethoxy being even more desirable. When h2 is 2, 3, or 4, the values ​​of each Rf... 7 They can be the same or different.

[0505] In formula (A10), R 43 It can be a halogen atom other than fluorine, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given and described in the explanation of formula (A1) regarding R. 1 and R 2 The examples representing hydrocarbon groups are the same, but not limited to these. Also, when h3 is 2, 3, or 4, each R... 43 They can be the same or different.

[0506] Furthermore, when h3 is 2, 3, or 4, multiple R 43 They can also bond with each other and form rings together with the carbon atoms they are bonded to. Specific examples of rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, and adamantane rings. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0507] Specific examples of the anions of repeating unit A8 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above, Me is a methyl group.

[0508] [Chemistry 135]

[0509]

[0510] [Chemistry 136]

[0511]

[0512] [Chemistry 137]

[0513]

[0514] [Chemistry 138]

[0515]

[0516] [Chemistry 139]

[0517]

[0518] [Chemistry 140]

[0519]

[0520] [Chemistry 141]

[0521]

[0522] [Chemistry 142]

[0523]

[0524] [Chemistry 143]

[0525]

[0526] [Chemistry 144]

[0527]

[0528] [Chemistry 145]

[0529]

[0530] [Chemistry 146]

[0531]

[0532] [Chemistry 147]

[0533]

[0534] Other specific examples of repeating unit A8 include paragraphs

[0043] to

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

[0067] to

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

[0057] to

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

[0020] to

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

[0067] to

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

[0075] to

[0084] of Japanese Patent Application Publication No. 7520258.

[0535] Specific examples of the anions of repeating unit A9 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above.

[0536] [Chemistry 148]

[0537]

[0538] [Chemistry 149]

[0539]

[0540] [Chemistry 150]

[0541]

[0542] [Chemistry 151]

[0543]

[0544] [Chemistry 152]

[0545]

[0546] [Chemistry 153]

[0547]

[0548] [Chemistry 154]

[0549]

[0550] [Chemistry 155]

[0551]

[0552] [Chemistry 156]

[0553]

[0554] [Chemistry 157]

[0555]

[0556] [Chemistry 158]

[0557]

[0558] Specific examples of the anions of repeating unit A10 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above.

[0559] [Chemistry 159]

[0560]

[0561] [Chemistry 160]

[0562]

[0563] [Chemistry 161]

[0564]

[0565] [Chemistry 162]

[0566]

[0567] [Chemistry 163]

[0568]

[0569] [Chemistry 164]

[0570]

[0571] [Chemistry 165]

[0572]

[0573] [Chemistry 166]

[0574]

[0575] [Chemistry 167]

[0576]

[0577] [Chemistry 168]

[0578]

[0579] [Chemistry 169]

[0580]

[0581] [Chemistry 170]

[0582]

[0583] [Chemistry 171]

[0584]

[0585] [Chemistry 172]

[0586]

[0587] [Chemistry 173]

[0588]

[0589] [Chemistry 174]

[0590]

[0591] [Chemistry 175]

[0592]

[0593] Specific examples of the anions of repeating unit A11 can be listed below, but are not limited to these. Also, in the following formula, R... A As mentioned above.

[0594] [Chemistry 176]

[0595]

[0596] In equations (A8) to (A11), A +The cation is a monium cation. Preferably, the monium cation is a sulfonium cation or a monium cation. Specific examples of the sulfonium cation may be the same as those shown in formula (Z-1) and formula (Z-3) described later, but are not limited to these. Specific examples of the monium cation may be the same as those shown in formula (Z-2), but are not limited to these.

[0597] The specific structures of repeating units A7~A11 can be exemplified by any combination of the aforementioned anions and cations.

[0598] Repeating units A7 to A11 are units that generate acid by irradiation with high-energy rays. It is believed that by containing these units in the polymer, acid diffusion is moderately suppressed, resulting in a pattern with reduced LER (Left-to-Rate) density. Furthermore, by containing these units in the polymer, the phenomenon of acid evaporating from the exposed areas and re-adhering to the unexposed areas during vacuum baking is suppressed, which is believed to be effective in reducing LER and minimizing shape degradation caused by undesirable film loss in the unexposed areas.

[0599] Among the repeating units A7 to A11, repeating units A8 to A11 are ideal for processing blank photomasks. Considering the suppression of acid diffusion and the optimal acid strength for designing acid-instable groups in polymers, repeating units A9, A10, and A11 are more ideal.

[0600] When the aforementioned polymer contains repeating units A7 to A11, it is ideal for the content of these repeating units to be 0.1 to 30 mol%, and even more ideal to be 0.5 to 20 mol%. Repeating units A7 to A11 can be used alone or in combination of two or more.

[0601] In the aforementioned polymer, it is ideal for the content of repeating units with an aromatic ring skeleton to be 65 mol% or more, more preferably 75 mol% or more, and more preferably 85 mol% or more. When repeating units A7 to A11 are excluded, it is preferable that all units have an aromatic ring skeleton.

[0602] The aforementioned polymers may also contain commonly used (meth)acrylate units protected by acid-insecure groups, (meth)acrylate units with lactone structures, hydroxyl groups other than phenolic hydroxyl groups, or other tightly bound groups. These repeating units can be used to fine-tune the properties of the resist film, but they may also be omitted.

[0603] Examples of (meth)acrylate units with the aforementioned binding groups include repeating units represented by formula (A12) (hereinafter also referred to as repeating unit A12), repeating units represented by formula (A13) (hereinafter also referred to as repeating unit A13), and repeating units represented by formula (A14) (hereinafter also referred to as repeating unit A14). These units are not acidic and can be used as auxiliary units to provide adhesion to the substrate or to adjust solubility.

[0604] [Chemistry 177]

[0605]

[0606] In equations (A12) to (A14), R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 51 It is -O- or methylene. R 52 It can be a hydrogen atom or a hydroxyl group. R 53 It is a saturated hydrocarbon group with 1 to 4 carbon atoms. i is 0, 1, 2 or 3.

[0607] When the polymer contains repeating units A12 to A14, it is ideal for the content to be 0 to 20 mol% of all repeating units in the aforementioned polymer, and even more ideal to be 0 to 10 mol%. Repeating units A12 to A14 can be used alone or in combination of two or more.

[0608] The aforementioned polymer can be synthesized by copolymerizing monomers, which require protection groups, using known methods, followed by a deprotection reaction as needed. The copolymerization reaction is not particularly limited, but free radical polymerization or anionic polymerization is preferred. For these methods, please refer to Japanese Patent Application Publication No. 2004-115630.

[0609] For the aforementioned polymer, a weight-average molecular weight (Mw) of 1000-50000 is preferred, and 2000-20000 is more ideal. If Mw is 1000 or higher, there is no risk of the previously known phenomenon of pattern head rounding leading to reduced resolution and LER degradation. On the other hand, if Mw is 50000 or lower, there is no risk of LER degradation, especially when forming patterns with a linewidth of 100 nm or lower. Furthermore, in this invention, Mw is a polystyrene conversion value obtained using gel permeation chromatography (GPC) with THF or DMF as a solvent.

[0610] The aforementioned polymer preferably exhibits a narrow dispersion with a molecular weight distribution (Mw / Mn) of 1.0 to 2.0, more preferably 1.0 to 1.9, and even more preferably 1.0 to 1.8. Such a narrow dispersion prevents the appearance of foreign matter on the pattern or deterioration of the pattern shape after development.

[0611] Furthermore, regarding the aforementioned basic polymer design, a dissolution rate of 10 nm / min or less for alkaline developer is ideal, 7 nm / min or less is better, and 5 nm / min or less is even more ideal. In more advanced generations, when the substrate coating is in the thin-film range (below 100 nm), the impact on pattern loss during alkaline development increases. When the polymer's alkaline dissolution rate exceeds 10 nm / min, the pattern collapses, making it impossible to form fine patterns. This is particularly pronounced in the fabrication of defect-free photomasks, where the development process exhibits a strong tendency to fail. In this invention, the dissolution rate of the basic polymer to the alkaline developer is calculated from the film loss after spin-coating a polymer solution (polymer concentration: 16.7% by mass, solvent: propylene glycol monomethyl ether acetate (PGMEA)) onto an 8-inch silicon wafer, baking at 100°C for 90 seconds to form a 1000 nm thick film, and then developing it with a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution at 23°C for 100 seconds.

[0612] (A) The base polymer of the component may also contain other polymers besides those mentioned above. Other polymers may also be those known in the past as base polymers used in resist compositions. There are no particular limitations on the content of other polymers as long as they do not impair the effects of the present invention.

[0613] [(B) Photoacid generator]

[0614] The chemically amplified positive resist composition of the present invention comprises a photoacid generator consisting of an onium salt represented by the following formula (B) as component (B).

[0615] [Chemistry 178]

[0616]

[0617] In formula (B), n1 is 0 or 1. When n1 is 0, it is a benzene ring; when n1 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with n1 of 0 is preferred. n2 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, n2 of 0 or 1 is preferred. n3 is 2, 3, or 4. However, when n1 is 0, 2 ≤ n2 + n3 ≤ 5; when n1 is 1, 2 ≤ n2 + n3 ≤ 7.

[0618] In equation (B), R 101The halogen atom can be a nitro group, cyano group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon oxy group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms; or it can be a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms containing heteroatoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine, but fluorine or iodine atoms are preferred. The hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, and tert-butyl; cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornel, and adamantyl; alkenyl groups with 2 to 20 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclohexenyl groups with 3 to 20 carbon atoms; aryl groups with 6 to 20 carbon atoms, such as phenyl and naphthyl; aralkyl groups with 7 to 20 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms. Similarly, a portion of the -CH2- group constituting the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. This can result in the presence of hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone, sulfonate, carboxylic anhydride, or haloalkyl groups. When n2 is 2, 3, or 4, each R... 101 They can be the same or different.

[0619] Furthermore, when n2 is 2, 3, or 4, multiple R 101 They can also bond to each other and form rings together with the carbon atoms they are bonded to. In this case, 5- to 8-membered rings are preferred.

[0620] In equation (B), Ar AL This refers to a group containing an acid-labile group, represented by the formula (AL). However, at least one Ar... AL and -SO3 - The bonded carbon atoms are adjacent to each other.

[0621] [Chemistry 179]

[0622]

[0623] In the formula, * represents an atomic bond.

[0624] In formula (AL), n4 is 0 or 1. When n4 is 0, it is a benzene ring; when n4 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with n4 of 0 is preferred. n5 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, n5 of 0 or 1 is preferred. n6 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, n6 of 0, 1, or 2 is preferred. n7 is 1 or 2. However, when n4 is 0, 1 ≤ n5 + n6 + n7 ≤ 5; when n4 is 1, 1 ≤ n5 + n6 + n7 ≤ 7.

[0625] In formula (AL), R 102 The halogen atom can be any halogen group other than fluorine, such as nitro, cyano, hydroxyl, or carboxyl. It can also be a hydrocarbon group with 1-20 carbon atoms containing heteroatoms, a hydrocarbon oxy group with 1-20 carbon atoms containing heteroatoms, a hydrocarbon thio group with 1-20 carbon atoms containing heteroatoms, or a hydrocarbon oxycarbonyl group with 2-20 carbon atoms containing heteroatoms. Examples of halogen atoms other than fluorine include chlorine, bromine, and iodine atoms, with iodine being preferred. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include [examples of halogen atoms and their relationships to R]. 101 The examples representing hydrocarbon groups are similar, but not limited to these. When n5 is 2, 3, or 4, each R 102 They can be the same or different.

[0626] Furthermore, when n5 is 2, 3, or 4, multiple R 102 They can also bond to each other and form rings together with the carbon atoms they are bonded to. In this case, 5- to 8-membered rings are preferred.

[0627] In formula (AL), R F It can be a fluorine atom, a fluorinated saturated hydrocarbon group with 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon oxygen group with 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon thio group with 1 to 6 carbon atoms, or a pentafluorothio group. Among these, a fluorine atom, trifluoromethyl, trifluoromethoxy, trifluoromethylthio, or pentafluorothio are preferred, with a fluorine atom, trifluoromethoxy, or pentafluorothio being more ideal. When n6 is 2, 3, or 4, each R... F They can be the same or different.

[0628] In equation (AL), when n6 is 2, 3, or 4, at least one R F and -OC(R) L1 (R) L2 (R) L3 The carbon atoms adjacent to each other on the aromatic ring bonded by -OC(R) are better bonded. L1 (R) L2 (R) L3 ) and R F Adjacent to each other, the acidity of the phenols generated after the deprotection of the tertiary ether increases, which improves their affinity for alkaline developing solutions and thus enhances the dissolution contrast.

[0629] In formula (AL), R L1 and R L2 Each is an independent hydrocarbon group having 1 to 12 carbon atoms. R L3 It consists of a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. R L1 R L2 and R L3 The -CH2- group of the represented hydrocarbon group may also be partially replaced by -O- or -S-. When the hydrocarbon group contains an aromatic ring or multiple bonds, part or all of the hydrogen atoms bonded to the carbon atoms constituting the aromatic ring or multiple bonds may also be replaced by halogen atoms, cyano groups, nitro groups, alkyl groups with 1 to 4 carbon atoms that may also contain halogen atoms, or alkoxy groups with 1 to 4 carbon atoms that may also contain halogen atoms. Furthermore, R... L1 and R L2 They can also bond to each other and form a ring with the carbon atoms they are bonded to, and a portion of the -CH2- in this ring can be replaced by -O- or -S-. But R L3 When the alicyclic structure, aromatic ring, and multiple bonds are all absent, R L1 and R L2 They bond to each other and together with the carbon atoms they are bonded to form a ring, and part of the -CH2- in this ring can also be replaced by -O- or -S-. That is, -C(R L1 (R) L2 (R) L3 The unstable acid group represented by ) must contain at least one cyclic structure or multiple bonds. Also, R L3 When R is a hydrogen atom L1 and R L2 It is preferable for them to bond to each other and form alicyclic rings with multiple bonds together with the carbon atoms they are bonded to.

[0630] In equation (AL), -C(R) L1 (R) L2 (R) L3 Examples of acid-instable groups represented by ) are listed below, but are not limited to these. * indicates an atomic bond between the group and the adjacent -O-.

[0631] [Chemistry 180]

[0632]

[0633] [Chemistry 181]

[0634]

[0635] [Chemistry 182]

[0636]

[0637] [Chemistry 183]

[0638]

[0639] [Chemistry 184]

[0640]

[0641] [Chemistry 185]

[0642]

[0643] [Chemistry 186]

[0644]

[0645] [Chemistry 187]

[0646]

[0647] [Chem.188]

[0648]

[0649] [Chemistry 189]

[0650]

[0651] [Chemistry 190]

[0652]

[0653] The onium salt represented by formula (B) is preferably represented by formula (B1).

[0654] [Chemistry 191]

[0655]

[0656] In the formula, n1, n2, n3, n5, n6, n7, R 101 R 102 R F and R L1 ~R L3 As mentioned above. Z + As will be described later.

[0657] The onium salt represented by formula (B1) is preferably represented by formula (B2).

[0658] [Chemistry 192]

[0659]

[0660] In the formula, n2, n3, n5, n6, n7, R 101 R 102 R F and RL1 ~R L3 As mentioned before. Z + As will be described later.

[0661] The anions of onium salts represented by formula (B) can be listed below, but are not limited to these. Furthermore, the bonding positions of various substituents on the aromatic ring can also be interchanged.

[0662] [Chemistry 193]

[0663]

[0664] [Chemistry 194]

[0665]

[0666] [Chemistry 195]

[0667]

[0668] [Chemistry 196]

[0669]

[0670] [Chemistry 197]

[0671]

[0672] [Chemistry 198]

[0673]

[0674] [Chemistry 199]

[0675]

[0676] [Chem.200]

[0677]

[0678] [Chemical Engineering 201]

[0679]

[0680] [Chemical Engineering 202]

[0681]

[0682] [Chemical Engineering 203]

[0683]

[0684] [Chemical 204]

[0685]

[0686] [Chemical Engineering 205]

[0687]

[0688] [Chemical Engineering 206]

[0689]

[0690] [Chemical 207]

[0691]

[0692] [Chemical Engineering 208]

[0693]

[0694] [Chemical Engineering 209]

[0695]

[0696] [Chemical 210]

[0697]

[0698] [Chemistry 211]

[0699]

[0700] [Chemistry 212]

[0701]

[0702] [Chemistry 213]

[0703]

[0704] [Chemistry 214]

[0705]

[0706] [Chemical 215]

[0707]

[0708] [Chemistry 216]

[0709]

[0710] [Chemistry 217]

[0711]

[0712] [Chemistry 218]

[0713]

[0714] [Chemistry 219]

[0715]

[0716] [Chem.220]

[0717]

[0718] [Chemistry 221]

[0719]

[0720] [Chemistry 222]

[0721]

[0722] [Chemistry 223]

[0723]

[0724] [Chemistry 224]

[0725]

[0726] [Chemistry 225]

[0727]

[0728] [Chemistry 226]

[0729]

[0730] [Chemistry 227]

[0731]

[0732] [Chemistry 228]

[0733]

[0734] [Chemistry 229]

[0735]

[0736] [Chemistry 230]

[0737]

[0738] [Chemistry 231]

[0739]

[0740] [Chemistry 232]

[0741]

[0742] [Chemistry 233]

[0743]

[0744] [Chemistry 234]

[0745]

[0746] [Chemistry 235]

[0747]

[0748] [Chemistry 236]

[0749]

[0750] [Chemistry 237]

[0751]

[0752] [Chemistry 238]

[0753]

[0754] [Chemistry 239]

[0755]

[0756] [Chemistry 240]

[0757]

[0758] [Chemistry 241]

[0759]

[0760] [Chemistry 242]

[0761]

[0762] [Chemistry 243]

[0763]

[0764] [Chemistry 244]

[0765]

[0766] [Chemistry 245]

[0767]

[0768] [Chemistry 246]

[0769]

[0770] [Chemistry 247]

[0771]

[0772] [Chemistry 248]

[0773]

[0774] [Chemistry 249]

[0775]

[0776] [Chemistry 250]

[0777]

[0778] [Chemistry 251]

[0779]

[0780] [Chemistry 252]

[0781]

[0782] [Chemistry 253]

[0783]

[0784] [Chemistry 254]

[0785]

[0786] [Chemistry 255]

[0787]

[0788] [Chemistry 256]

[0789]

[0790] [Chemistry 257]

[0791]

[0792] [Chemistry 258]

[0793]

[0794] [Chemistry 259]

[0795]

[0796] [Chemistry 260]

[0797]

[0798] [Chemistry 261]

[0799]

[0800] [Chemistry 262]

[0801]

[0802] [Chemistry 263]

[0803]

[0804] [Chemistry 264]

[0805]

[0806] [Chemistry 265]

[0807]

[0808] [Chemistry 266]

[0809]

[0810] [Chemistry 267]

[0811]

[0812] [Chemistry 268]

[0813]

[0814] [Chemistry 269]

[0815]

[0816] [Chemistry 270]

[0817]

[0818] [Chemistry 271]

[0819]

[0820] [Chemistry 272]

[0821]

[0822] [Chemistry 273]

[0823]

[0824] [Chemistry 274]

[0825]

[0826] [Chemistry 275]

[0827]

[0828] [Chemistry 276]

[0829]

[0830] [Chemistry 277]

[0831]

[0832] [Chemistry 278]

[0833]

[0834] [Chemistry 279]

[0835]

[0836] [Chemistry 280]

[0837]

[0838] [Chemistry 281]

[0839]

[0840] [Chemistry 282]

[0841]

[0842] [Chemistry 283]

[0843]

[0844] [Chemistry 284]

[0845]

[0846] [Chemistry 285]

[0847]

[0848] [Chemistry 286]

[0849]

[0850] [Chemistry 287]

[0851]

[0852] [Chemistry 288]

[0853]

[0854] [Chemistry 289]

[0855]

[0856] [Chemistry 290]

[0857]

[0858] [Chemistry 291]

[0859]

[0860] [Chemistry 292]

[0861]

[0862] [Chemistry 293]

[0863]

[0864] [Chemistry 294]

[0865]

[0866] [Chemistry 295]

[0867]

[0868] [Chemistry 296]

[0869]

[0870] [Chemistry 297]

[0871]

[0872] [Chemistry 298]

[0873]

[0874] [Chemistry 299]

[0875]

[0876] [Chemical 300]

[0877]

[0878] [Chemical Engineering 301]

[0879]

[0880] [Chemical 302]

[0881]

[0882] [Chemical 303]

[0883]

[0884] [Chemical 304]

[0885]

[0886] [Chemical 305]

[0887]

[0888] [Chemical 306]

[0889]

[0890] [Chemical 307]

[0891]

[0892] [Chemical 308]

[0893]

[0894] [Chemical 309]

[0895]

[0896] [Chemical 310]

[0897]

[0898] [Chemistry 311]

[0899]

[0900] [Chemistry 312]

[0901]

[0902] [Chemistry 313]

[0903]

[0904] [Chemical 314]

[0905]

[0906] [Chemical 315]

[0907]

[0908] [Chemistry 316]

[0909]

[0910] [Chemistry 317]

[0911]

[0912] [Chemistry 318]

[0913]

[0914] [Chemistry 319]

[0915]

[0916] [Chem.320]

[0917]

[0918] In equation (B), Z + The cation is a sulfonium cation. Preferably, the sulfonium cation represented by formula (Z-1) or the sulfonium cation represented by formula (Z-2) is a sulfonium cation.

[0919] [Chemistry 321]

[0920]

[0921] In equations (Z-1) and (Z-2), R ct1 ~R ct5 Each is an independent halogen atom, or may contain a hydrocarbon group with 1 to 30 carbon atoms and heteroatoms.

[0922] R ct1 ~R ct5 Specific examples of halogen atoms that can be represented include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc.

[0923] R ct1 ~R ct5The hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 30 carbons such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups with 3 to 30 carbons such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 30 carbons such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 30 carbons such as cyclohexenyl; aryl groups with 6 to 30 carbons such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 30 carbons such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining these, with aryl being preferred. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group 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, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0924] Also, R ct1 and R ct2 They can also bond to each other and form rings together with the sulfur atoms they are bonded to. Specific examples of the aforementioned ring structures can be shown in the following formulas, etc.

[0925] [Chemistry 322]

[0926]

[0927] In the formula, the dashed line represents R. ct3 Atomic bonds.

[0928] Specific examples of sulfonium cations represented by formula (Z-1) may be found in paragraphs

[0102] to

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

[0070] to

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

[0929] Specific examples of citric acid represented by formula (Z-2) can be found in paragraph

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

[0930] Z + The onium cation represented by the following formula (Z-3) is also ideal.

[0931] [Chemistry 323]

[0932]

[0933] In formula (Z-3), m1 is 0 or 1. When m1 is 0, it is a benzene ring; when m1 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with m1 = 0 is preferred. m2 is 0 or 1. When m2 is 0, it is a benzene ring; when m2 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with m2 = 0 is preferred. m3 is 0 or 1. When m3 is 0, it is a benzene ring; when m3 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with m3 = 0 is preferred.

[0934] In formula (Z-3), m4 is 0, 1, 2, 3, or 4. The more iodine atoms in the cationic structure, the better the absorption, especially for EUV, but the less solvent-soluble it becomes, raising concerns about precipitation in the resist composition. Therefore, m4 is preferred to be 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0935] In formula (Z-3), m5 can be 0, 1, 2, 3, or 4. Considering the availability of raw materials, m5 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better. m6 can be 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, m6 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better. m7 can be 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, m7 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0936] In formula (Z-3), m8 is 0, 1, or 2. Considering the availability of raw materials, m8 being 0 or 1 is preferred. m9 is 0, 1, or 2. Considering the availability of raw materials, m9 being 0 or 1 is preferred. m10 is 0, 1, or 2. Considering the availability of raw materials, m10 being 0 or 1 is preferred.

[0937] In formula (Z-3), m11 is 0 or 1. When m11 is 0, it is a benzene ring; when m11 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with m11 of 0 is preferred.

[0938] In formula (Z-3), m12 is 0, 1, 2, 3, or 4. The more iodine atoms in the cation structure, the better the absorption, especially for EUV, but the less solvent-soluble it becomes, raising concerns about precipitation in the resist composition. Therefore, m12 is preferred to be 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0939] In formula (Z-3), m13 is 0, 1, or 2. Considering the availability of raw materials, m13 being 0 or 1 is preferred. m14 is 0, 1, or 2. Considering the synthesis aspect, m14 being 0 or 1 is preferred.

[0940] However, when m1 is 0, the condition is 0 ≤ m6 + m9 ≤ 4; when m1 is 1, the condition is 0 ≤ m6 + m9 ≤ 6. When m2 is 0, the condition is 0 ≤ m7 + m10 ≤ 4; when m2 is 1, the condition is 0 ≤ m7 + m10 ≤ 6. When m3 is 0, the condition is 1 ≤ m4 + m5 + m8 + m14 ≤ 4; when m3 is 1, the condition is 1 ≤ m4 + m5 + m8 + m14 ≤ 6. When m11 is 0, the condition is 0 ≤ m12 + m13 ≤ 4; when m11 is 1, the condition is 0 ≤ m12 + m13 ≤ 6. Also, m4 + m12 ≥ 1.

[0941] In equation (Z-3), R F1 ~R F3 Each of these is independently a fluorine atom, a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon oxygen group having 1 to 6 carbon atoms, or a fluorinated saturated hydrocarbon thio group having 1 to 6 carbon atoms. Among these, trifluoromethyl, trifluoromethoxy, and trifluorothiomethoxy are preferred. When m5 is 2, 3, or 4, each R... F1 They can be the same or different. When m6 is 2, 3, 4, 5 or 6, each R F2 They can be the same or different. When m7 is 2, 3, 4, 5 or 6, each R F3 They can be the same or different.

[0942] In equation (Z-3), R ct6 ~R ct9 The group can be a halogen atom other than iodine and fluorine atoms, a nitro group, a cyano group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. The hydrocarbon group, hydrocarbon oxy group, and hydrocarbon thio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be given and described in the explanation of formula (A) regarding R. 1 The examples of the hydrocarbon groups are the same. Furthermore, some or all of the hydrogen atoms in the hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon sulfide group can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group 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, 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.

[0943] Also, when m8 is 2, there are 2 Rs. ct6 They can be the same or different, 2 Rs ct6 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m9 is 2, there are 2 R atoms. ct7 They can be the same or different, 2 Rs ct7They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m10 is 2, the two R atoms... ct8 They can be the same or different, 2 Rs ct8 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m13 is 2, there are 2 R atoms. ct9 They can be the same or different, 2 Rs ct9 They can also bond with each other and form rings together with the carbon atoms they are bonded to. Specific examples of rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, and adamantane rings. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, they may contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0944] Furthermore, the sum of S in the sulfonium cation represented by formula (Z-3) + Directly bonded aromatic rings can also bond to each other and S + Together they form a ring. Specific examples of the aforementioned ring structure can be represented by the following formulas, etc.

[0945] [Chemistry 324]

[0946]

[0947] In equation (Z-3), L A and L B Each bond can be independently a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. Among these, L... A Single bonds, ether bonds, ester bonds, or sulfonate bonds are preferred, with ester bonds or sulfonate bonds being even more preferred. L B Single bonds, ether bonds, or ester bonds are preferred, with single bonds being even better.

[0948] In equation (Z-3), X L It is a single bond, or may contain heteroatoms, of 1 to 40 carbon atoms. The aforementioned hydrocarbon group can be linear, branched, or cyclic; specific examples include alkyldiyl groups and cyclic saturated hydrocarbon groups. Specific examples of the aforementioned heteroatoms include oxygen atoms, nitrogen atoms, and sulfur atoms.

[0949] X L Examples of hydrocarbon groups containing 1 to 40 carbon atoms and also representing heteroatoms are listed below, but are not limited to these. Furthermore, in the following formula, * represents and L respectively. A and LB Atomic bonds.

[0950] [Chemistry 325]

[0951]

[0952] [Chemistry 326]

[0953]

[0954] [Chemistry 327]

[0955]

[0956] [Chemistry 328]

[0957]

[0958] Among these, X L -0~X L -22 and X L -47~X L -61 is better.

[0959] The sulfonium cation represented by formula (Z-3) is preferably represented by formula (Z-3-1).

[0960] [Chemistry 329]

[0961]

[0962] In the formula, m4~m10, m12~m14, R F1 ~R F3 R ct6 ~R ct9 L A L B and X L As mentioned above.

[0963] The cation represented by formula (Z-3-1) is preferably represented by formula (Z-3-2).

[0964] [Chemistry 330]

[0965]

[0966] In the formula, m4~m10, R F1 ~R F3 and R ct6 ~R ct8 As mentioned above.

[0967] Specific examples of sulfonium cations represented by formula (Z-3) are listed below, but are not limited to these. Also, in the following formula, Me is a methyl group.

[0968] [Chemistry 331]

[0969]

[0970] [Chemistry 332]

[0971]

[0972] [Chemistry 333]

[0973]

[0974] [Chemistry 334]

[0975]

[0976] [Chemistry 335]

[0977]

[0978] [Chemistry 336]

[0979]

[0980] [Chemistry 337]

[0981]

[0982] [Chemistry 338]

[0983]

[0984] [Chemistry 339]

[0985]

[0986] [Transformation 340]

[0987]

[0988] [Chemistry 341]

[0989]

[0990] [Chemistry 342]

[0991]

[0992] [Chemistry 343]

[0993]

[0994] [Chemistry 344]

[0995]

[0996] [Chemistry 345]

[0997]

[0998] [Chemistry 346]

[0999]

[1000] [Chemistry 347]

[1001]

[1002] [Chemistry 348]

[1003]

[1004] [Chemistry 349]

[1005]

[1006] [Chemical 350]

[1007]

[1008] [Chemistry 351]

[1009]

[1010] [Chemistry 352]

[1011]

[1012] [Chemistry 353]

[1013]

[1014] [Chemistry 354]

[1015]

[1016] [Chemistry 355]

[1017]

[1018] [Chemistry 356]

[1019]

[1020] [Chemistry 357]

[1021]

[1022] [Chemistry 358]

[1023]

[1024] Specific examples of the aforementioned onium salts can be any combination of the aforementioned anions and cations.

[1025] The aforementioned onium salt can be synthesized using known methods. Specifically, it can be synthesized using the synthesis examples described in Japanese Patent No. 7032549

[0363] to

[0368] , but is not limited to this synthesis method.

[1026] In the chemically amplified resist composition of the present invention, the onium salt represented by formula (B) is an onium salt of an aromatic sulfonic acid, and therefore can be irradiated with high-energy rays to produce an acid of moderate strength. Furthermore, the aforementioned onium salt is characterized by having 2, 3, or 4 atoms in the -SO3 group. - The bonded aromatic ring contains an aryl group with an unstable ether-type acid group. And -SO3 - The bonded aromatic ring consists of at least one aryl group and -SO3. - The bonded carbon atoms have good affinity between adjacent carbon atoms, with two atoms bonded to -SO3. - The bonding between adjacent carbon atoms is better. This is achieved through the presence of carbon atoms in -SO3. -The presence of large aromatic ring bonds between the two adjacent carbon atoms of the bonded carbon atom can shield the area near the generated sulfonic acid, thereby inhibiting excessive deprotection reactions of the acid-labile groups in the base polymer. It is preferable that the aforementioned ether-type acid-labile group is a cyclic tertiary ether, as the cyclic structure lowers the activation energy for acid deprotection, facilitating the deprotection reaction. On the other hand, when the aforementioned ether-type acid-labile group lacks a cyclic ether structure, the carbon atom bonded to the ether oxygen has at least one double bond, aromatic ring, or triple bond. The generation of allyl cations, benzyl cations, or propargyl cations serves as the driving force, thereby facilitating deprotection reactions due to acid. Japanese Patent No. 7032549 discloses a structure obtained by introducing tert-butyl ether, acetal, acetal, tert-butoxycarbonyl, and tert-butyl ester as acid-insensitive functional groups. However, acetal and tert-butoxycarbonyl are acid-sensitive functional groups, so there are concerns about their stability. Tert-butyl ether and tert-butyl ester are considered difficult to undergo sufficient deprotection reactions due to their high activation energies in acid-induced deprotection reactions. In the onmium salt represented by formula (B), it is preferable that the carbon atom adjacent to the carbon atom bonded to the ether-type acid-insensitive group has a fluorine atom or a fluorine-containing functional group. A fluorine atom or a fluorine-containing functional group can improve the solubility in the solvent, enabling it to dissolve uniformly. Furthermore, the ether-type acid-insensitive group will generate phenols after the acid-induced deprotection reaction; the presence of a fluorine atom or a fluorine-containing functional group at the adjacent position can increase the acidity of the phenols. Phenolic compounds are characterized by their low swelling in alkaline developers, which increases their affinity for alkaline developers during development, thereby suppressing development residue in the exposed areas and improving dissolution contrast. Japanese Patent No. 7531671 describes a similar structure using aromatic sulfonic acid anions with tertiary ester-type acid-insecure groups. Tertiary esters generate carboxyl groups after acid deprotection, which are known to swell in alkaline developers, thus degrading the LER (Left-Ratio) of the resist pattern. The multiple aromatic rings in the anion exhibit improved compatibility with the aromatic rings of the base polymer (π-π stacking interaction), and are expected to suppress excessive acid diffusion. Due to these effects, an acid of appropriate strength and controlled acid diffusion can be uniformly generated in the resist film, resulting in patterns with good resolution and low LER even in fine patterns. Positive resist compositions using alkaline developers can achieve patterns with good rectangularity due to their moderate dissolution inhibition.

[1027] In the chemically amplified positive resist composition of the present invention, the content of (B) photoacid generator is ideally 0.1 to 40 parts by mass relative to 80 parts by mass of (A) base polymer, and more ideally 1 to 20 parts by mass. If the content of (B) photoacid generator is within the aforementioned range, it will generate an amount of acid necessary for deprotection of acid-labile groups, and also exhibit good storage stability. (B) Photoacid generator can be used alone or in combination of two or more.

[1028] [(C) Organic solvent]

[1029] The chemically amplified positive resist composition of the present invention may also include an organic solvent as component (C). There are no particular limitations on the aforementioned organic solvent as long as it can dissolve each component. Examples of such organic solvents include: ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone as described in paragraphs

[0144] to

[0145] of Japanese Patent Application Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; propylene glycol monomethyl ether (PGME), ethylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene ... Ethers such as glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as PGMEA, propylene glycol monoethyl ether acetate, ethyl lactate (EL), ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as γ-butyrolactone; and mixed solvents of these. When using acetals with unstable acid groups, high-boiling-point alcohol solvents can be added to accelerate the deprotection reaction of the acetal. Specifically, diethylene glycol, propylene glycol, glycerol, 1,4-butanediol, and 1,3-butanediol can be added.

[1030] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, PGME, cyclohexanone, EL, γ-butyrolactone, and their mixed solvents are preferred.

[1031] When the chemically amplified positive resist composition of the present invention contains (C) organic solvent, its content is preferably 200 to 10,000 parts by mass relative to 80 parts by mass of (A) base polymer, and more preferably 400 to 5,000 parts by mass. (C) Organic solvent can be used alone or in combination of two or more.

[1032] [(D) Quenching agent]

[1033] The chemically amplified positive resist composition of the present invention may, as needed, include a quencher as component (D). Furthermore, in the present invention, a quencher refers to a compound that captures acid generated from an acid-generating agent. This suppresses the diffusion rate of acid generated from the acid-generating agent within the resist film, and when the substrate is made of a chromium-containing material on its outermost surface, the influence of acid generated within the resist film on the chromium-containing material can also be suppressed.

[1034] The aforementioned quenching agents can be exemplified by known basic compounds. Examples of known basic compounds include first-, second-, and third-order aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds with carboxyl groups, nitrogen-containing compounds with sulfonyl groups, nitrogen-containing compounds with hydroxyl groups, nitrogen-containing compounds with hydroxyphenyl groups, alcoholic nitrogen-containing compounds, amides, imides, 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 having hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, or sulfonate bonds, or compounds with carbamate groups described in Japanese Patent No. 3790649, are preferred. Ideal examples include tris[2-(methoxymethoxy)ethyl]amine, tris[2-(methoxymethoxy)ethyl]amine-N-oxide, dibutylaminobenzoic acid, morpholine derivatives, imidazole derivatives, etc. By adding such basic compounds, for example, the diffusion rate of the acid in the resist film can be further controlled, or the shape can be corrected.

[1035] Furthermore, examples of quenchers mentioned above include onium salts such as sulfonium salts, uranium salts, and ammonium salts of α-unfluorinated carboxylic acids, as described in Japanese Patent Application Publication No. 2008-158339. While α-fluorinated sulfonic acids, imine acids, or methylated acids are necessary for deprotecting unstable acid groups, salt exchange with α-unfluorinated onium salts releases α-unfluorinated carboxylic acids. Since α-unfluorinated carboxylic acids hardly cause deprotection reactions, they function as quenchers.

[1036] Onium salts of carboxylic acids that are not fluorinated at the α-position, for example, those represented by the formula (D1).

[1037] [Chemistry 359]

[1038]

[1039] In equation (D1), R 201 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain hydrogen atoms or heteroatoms, but excludes hydrogen atoms bonded to the carbon atom at the α position of the carboxyl group that are replaced by fluorine atoms or fluoroalkyl groups.

[1040] R 201 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, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, and tricyclic [5.2.1.0]. 2,6[Cyclic saturated hydrocarbon groups with 3-40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; alkenyl groups with 2-40 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated aliphatic hydrocarbon groups with 3-40 carbon atoms, such as cyclohexenyl; aryl groups with 6-40 carbon atoms, such as phenyl, naphthyl, alkylphenyl (2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butylphenyl, etc.), di- or trialkylphenyl (2,4-dimethylphenyl, 2,4,6-triisopropylphenyl, etc.), alkylnaphthyl (methylnaphthyl, ethylnaphthyl, etc.), and dialkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); and aralkyl groups with 7-40 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl.]

[1041] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, cyano groups, carbonyl groups, ether bonds, thioether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc. Examples of hydrocarbon groups containing heteroatoms include 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 aryloxoalkyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl.

[1042] In equation (D1), Mq A + The aforementioned onion cations are preferably sulfonium, monium, or ammonium cations, with sulfonium or monium cations being more ideal. Specific examples of the aforementioned sulfonium cations are the same as those shown in formula (Z-1) and formula (Z-3). Specific examples of the aforementioned monium cations are the same as those shown in formula (Z-2).

[1043] The anions of onium salts represented by formula (D1) can be listed below, but are not limited to these.

[1044] [Hua360]

[1045]

[1046] [Chemistry 361]

[1047]

[1048] [Chemistry 362]

[1049]

[1050] [Chem.363]

[1051]

[1052] The aforementioned quenching agent should also be a sulfonium salt of a carboxylic acid containing an iodinated benzene ring, represented by the formula (D2).

[1053] [Chem.364]

[1054]

[1055] In equation (D2), 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.

[1056] In equation (D2), R 211 It can be a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, a nitro group, a cyano group, a saturated hydrocarbon group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group with 1 to 6 carbon atoms, a saturated hydrocarbon sulfonyl group with 2 to 6 carbon atoms, or a -N(R) group. 211A )-C(=O)-R 211B or -N(R) 211A )-C(=O)-OR 211B The hydrogen atoms of the saturated hydrocarbon group, saturated hydrocarbon oxygen group, saturated hydrocarbon carbonyl oxygen group, or saturated hydrocarbon sulfonyl oxygen group may also be substituted with halogen atoms. 211A It consists of a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 211B It is a saturated hydrocarbon group with 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group with 2 to 8 carbon atoms. When t and / or u is 2 or more, each R 211 They can be the same or different.

[1057] In equation (D2), L 21 It is a single bond or a (u+1) valence linking group with 1 to 20 carbon atoms, and may also contain at least one selected from ether bonds, carbonyl groups, ester bonds, amide bonds, sulfonyl lactone rings, lactam rings, carbonate bonds, halogen atoms, hydroxyl groups, and carboxyl groups. The aforementioned saturated hydrocarbon groups, saturated hydrocarbon oxy groups, saturated hydrocarbon carbonyl oxy groups, and saturated hydrocarbon sulfonyl oxy groups may be straight-chain, branched, or cyclic.

[1058] In equation (D2), R 212 R 213 and R 214Each group is an independent halogen atom, or may contain heteroatoms, and consists of a hydrocarbon group with 1 to 20 carbon atoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, alkenyl groups with 2 to 20 carbon atoms, aryl groups with 6 to 20 carbon atoms, and aralkyl groups with 7 to 20 carbon atoms. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by hydroxyl, carboxyl, halogen, oxo, cyano, nitro, sulfonyl lactone ring, sulfonyl, or sulfonium salt-containing groups, and part of the -CH2- group in the aforementioned hydrocarbon group can be replaced by ether, ester, carbonyl, amide, carbonate, or sulfonate bonds. Also, R... 212 and R 213 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[1059] Specific examples of compounds represented by formula (D2) can be found in Japanese Patent Application Publication No. 2017-219836. Compounds represented by formula (D2) exhibit high absorption, high sensitization effect, and high acid diffusion control effect.

[1060] The aforementioned quenching agent may also be a nitrogen-containing carboxylate compound represented by the following formula (D3).

[1061] [Chem365]

[1062]

[1063] In formula (D3), R 221 ~R 224 Each is independently a hydrogen atom, -L 22 -CO2 - Or it may contain a hydrocarbon group with 1 to 20 carbon atoms and heteroatoms. R 221 With R 222 R 222 With R 223 、or R 223 With R 224 They can also bond to each other and form rings together with the carbon atoms they are bonded to. 22 It is a single bond or may contain a heteroatom and consist of a hydrocarbon group with 1 to 20 carbon atoms. R 225 It consists of a hydrogen atom or a hydrocarbon group with 1 to 20 carbon atoms that may also contain heteroatoms.

[1064] In equation (D3), ring R r The formula refers to a 2-6 carbon ring containing carbon and nitrogen atoms, wherein some or all of the hydrogen atoms bonded to the carbon atoms of the ring may be replaced by a hydrocarbon group with 1-20 carbon atoms, or -L 22 -CO2 -A part of -CH2- of the ring may also be substituted by a sulfur atom, an oxygen atom or a nitrogen atom. Said ring may be an alicyclic ring or an aromatic ring; a 5-membered ring or 6-membered ring is preferred, and specific examples thereof include a pyridine ring, a pyrrole ring, a pyrrolidine ring, a piperidine ring, a pyrazole ring, an imidazoline ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, an imidazoline ring, an oxazole ring, a thiazole ring, a morpholine ring, a thiazine ring, a triazole ring and the like.

[1065] The carboxylate onium salt represented by formula (D3) has at least one -L 22 -CO2 - group. That is, at least one of R 221 to R 224 is -L 22 -CO2 - and / or at least one hydrogen atom bonded to a carbon atom of ring R r is substituted by -L 22 -CO2 - substituent.

[1066] In formula (D3), Mq B + is a sulfonium cation, an iodonium cation or an ammonium cation, with a sulfonium cation being preferred. Specific examples of said sulfonium cation include the same examples as those exemplified for the sulfonium cation represented by formula (Z-1) and the sulfonium cation represented by formula (Z-3).

[1067] Anions of the compound represented by formula (D3) are listed below, but are not limited thereto.

[1068] [Chem 366]

[1069]

[1070] [Chem 367]

[1071]

[1072] [Chem 368]

[1073]

[1074] [Chem 369]

[1075]

[1076] [Chem 370]

[1077]

[1078] [Chem 371]

[1079]

[1080] 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.

[1081] [Chemistry 372]

[1082]

[1083] The aforementioned quenching agents include, for example, the polymer-type quenching agent disclosed in Japanese Patent Application Publication No. 2008-239918. This quenching agent improves the rectangularity of the resist pattern by aligning with the surface of the resist film. The polymer-type quenching agent also prevents film loss and rounding of the pattern top when using a protective film for immersion exposure.

[1084] When the chemically amplified positive resist composition of the present invention includes (D) a quencher, its content is preferably 0 to 50 parts by mass relative to 80 parts by mass of the aforementioned (A) base polymer, and more preferably 0.1 to 40 parts by mass. The aforementioned quencher can be used alone or in combination of two or more.

[1085] [(E) Polymers containing fluorine atoms]

[1086] The chemically amplified 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 treatment of the antistatic film material coated on the resist film, and suppress unintended pattern degradation, may also contain a fluorine-containing polymer as component (E). This fluorine-containing polymer contains at least one repeating unit selected from the following formulas: (E1) (hereinafter also referred to as repeating unit E1.), (E2) (hereinafter also referred to as repeating unit E2.), (E3) (hereinafter also referred to as repeating unit E3.), and (E4) (hereinafter also referred to as repeating unit E4.), and may also further contain at least one repeating unit selected from the following formulas: (E5) (hereinafter also referred to as repeating unit E5.) and (E6) (hereinafter also referred to as repeating unit E6.). The aforementioned polymers containing fluorine atoms also act as surfactants, thus preventing insoluble substances that may be generated during the development process from re-adhering to the substrate, and therefore also effective against development defects.

[1087] [Chemistry 373]

[1088]

[1089] In equations (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. R BEach can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R C Each can be independently a hydrogen atom or a methyl group. R 301 R 302 R 304 and R 305 Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. R 303 R 306 R 307 and R 308 Each is independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-labile group, R 303 R 306 R 307 and R 308 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group may also be inserted between the carbon-carbon bonds. R 309 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, consisting of hydrogen atoms or carbon-carbon bonds, with heteroatom-containing groups inserted between them. When j1 is 2 or 3, each R 309 They can be the same or different. R 310 It is a straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which heteroatoms may be inserted between carbon-carbon bonds. When j2 is 2 or more, each R 310 They can be the same or different. R 311 A saturated hydrocarbon group with 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, wherein a portion of the -CH2- group of the aforementioned saturated hydrocarbon group may also be replaced by an ester bond or an ether bond. 1 It is a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms or a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms. W 2 It is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-. * represents an atomic bond with a carbon atom in the main chain. W 3 For single bonds, -O-, *-C(=O)-OW 31 -W 32 -or *-C(=O)-N(H)-W 31 -W 32 -. W 31 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms. W 32 These are single bonds, ester bonds, ether bonds, or sulfonamide bonds. * indicates an atomic bond with a carbon atom in the main chain.

[1090] In equations (E1) and (E2), R 301 R 302 R 304 and R 305The saturated hydrocarbon groups representing 1 to 10 carbon atoms can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 10 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; and cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, and norbornel. Among these, saturated hydrocarbon groups with 1 to 6 carbon atoms are preferred.

[1091] In equations (E1) to (E4), R 303 R 306 R 307 and R 308 The hydrocarbon group representing 1 to 15 carbon atoms can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 15 carbon atoms, alkenyl groups with 2 to 15 carbon atoms, and alkynyl groups with 2 to 15 carbon atoms, but alkyl groups with 1 to 15 carbon atoms are preferred. In addition to the aforementioned alkyl groups, examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, and n-pentadecayl. Furthermore, fluorinated hydrocarbon groups can be groups in which some or all of the hydrogen atoms bonded to the carbon atoms of the aforementioned hydrocarbon groups are replaced by fluorine atoms.

[1092] In formula (E4), W 1 The (k+1) valence hydrocarbon group representing 1 to 20 carbon atoms can be exemplified by alkyl groups with 1 to 20 carbon atoms or cyclic saturated hydrocarbon groups with 3 to 20 carbon atoms that have removed k hydrogen atoms. Also, W 1 Examples of (k+1) valent fluorinated hydrocarbon groups with carbon numbers of 1 to 20 include groups obtained by replacing at least one hydrogen atom of the aforementioned (k+1) valent hydrocarbon group with a fluorine atom.

[1093] Specific examples of repeating units E1~E4 can be listed below, but are not limited to these. Also, in the following formula, R... B As mentioned above.

[1094] [Chemistry 374]

[1095]

[1096] [Chemistry 375]

[1097]

[1098] [Chemistry 376]

[1099]

[1100] In equation (E5), R 309 and R 310Examples of hydrocarbon groups with 1 to 5 carbon atoms include alkyl, alkenyl, and ynyl groups, with alkyl being preferred. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and n-pentyl. Furthermore, groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms may be inserted between the carbon-carbon bonds of the aforementioned hydrocarbon groups.

[1101] In equation (E5), -OR 309 A hydrophilic group is preferred. In this case, R 309 Alkyl groups with 1 to 5 carbon atoms that have an oxygen atom inserted between carbon-carbon bonds are preferred.

[1102] In equation (E5), W 2 *-C(=O)-O- or *-C(=O)-N(H)- are preferred. Furthermore, R C Methyl is preferred. 2 The presence of a carbonyl group enhances the ability of the antistatic membrane to capture acids. Furthermore, R... C If the methyl group is used, it becomes a rigid polymer with a higher glass transition temperature (Tg), thus inhibiting acid diffusion. As a result, the resist film exhibits good stability over time, and its resolution and pattern shape do not deteriorate.

[1103] Repeating unit E5 can be listed below, but is not limited to these. Also, in the following formula, R... C As mentioned above.

[1104] [Chemistry 377]

[1105]

[1106] [Chemistry 378]

[1107]

[1108] In equation (E6), W 3 The saturated alkylene groups representing carbons 1 to 10 can be linear, branched, or cyclic. Specific examples include methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, and 1,1-dimethylethane-1,2-diyl.

[1109] In equation (E6), R 311 The saturated hydrocarbon group with 1 to 20 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom, can be 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.

[1110] Repeating unit E6 can be listed below, but is not limited to these. Also, in the following formula, R... C As mentioned above.

[1111] [Chemistry 379]

[1112]

[1113] [Chemistry 380]

[1114]

[1115] [Chemistry 381]

[1116]

[1117] [Chemistry 382]

[1118]

[1119] The content of repeating units E1 to E4 is preferably 15 to 95 mol% of all repeating units in the aforementioned polymer containing fluorine atoms, and more preferably 20 to 85 mol%. The content of repeating units E5 and / or E6 is preferably 5 to 85 mol% of all repeating units in the aforementioned polymer containing fluorine atoms, and more preferably 15 to 80 mol%. Repeating units E1 to E6 can be used alone or in combination of two or more.

[1120] (E) Polymers containing fluorine atoms may also contain other repeating units besides the aforementioned repeating units. Examples of such repeating units can be found in paragraphs

[0046] to

[0078] of Japanese Patent Application Publication No. 2014-177407. (E) When polymers containing fluorine atoms contain other repeating units, it is preferable that their content is 50 mol% or less of all repeating units in the aforementioned polymers containing fluorine atoms.

[1121] (E) Polymers containing fluorine atoms can be synthesized by copolymerizing monomers, which require protection groups, using known methods, followed by a deprotection reaction as needed. The copolymerization reaction is not particularly limited, but free radical polymerization and anionic polymerization are preferred. These methods are described in Japanese Patent Application Publication No. 2004-115630.

[1122] (E) For polymers containing fluorine atoms, a Mw of 2000~50000 is preferred, and 3000~20000 is even better. If Mw is above 2000, acid does not diffuse, resolution does not deteriorate, and stability over time is not compromised. If Mw is below 50000, solubility in solvents is sufficient, and coating defects do not occur. Furthermore, for polymers containing fluorine atoms, an Mw / Mn ratio of 1.0~2.2 is preferred, and 1.0~1.7 is even better.

[1123] When the chemically amplified positive resist composition of the present invention includes (E) a polymer containing fluorine atoms, its content is preferably 0.01 to 30 parts by mass relative to 80 parts by mass of the base polymer (A), and more preferably 0.1 to 20 parts by mass. The polymer containing fluorine atoms (E) can be used alone or in combination of two or more.

[1124] [(F) Other photoacid generating agents]

[1125] The chemically amplified positive resist composition of the present invention may also include photoacid generators other than those composed of onium salts represented by formula (B) as component (F). There are no particular limitations on the aforementioned other photoacid generators if they are compounds that generate acid upon irradiation by high-energy rays. Ideal photoacid generators include sulfonium salts, sulfonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate type photoacid generators, etc.

[1126] Specific examples of other photoacid generators mentioned above include nonafluorobutane sulfonate, the partially fluorinated sulfonate described in paragraphs

[0247] to

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

[0261] to

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

[0261] to

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

[0122] to

[0142] of Japanese Patent Application Publication No. 5368270, the author described in paragraphs

[0080] to

[0081] of Japanese Patent Application Publication No. 6248882, the author described in paragraphs

[0027] to

[0029] of Japanese Patent Application Publication No. 6648726, the author described in paragraphs

[0029] to

[0034] of Japanese Patent Application Publication No. 7067271, and the author described in paragraphs [002... [8]~

[0029] Paragraphs from Japanese Patent Application Publication No. 2024-104830

[0037] ~

[0060] Paragraphs from Japanese Patent Application Publication No. 2025-000201

[0040] ~

[0071] Paragraphs from Japanese Patent Application Publication No. 2023-177038

[0039] ~

[0066] Paragraphs from Japanese Patent Application Publication No. 2024-1 The authors of paragraphs

[0033] to

[0093] of Japanese Patent No. 40135, paragraphs

[0220] to

[0225] of Japanese Patent No. 7032549, paragraphs

[0229] to

[0231] of Japanese Unexamined Patent Application No. 2024-077330, and paragraphs

[0056] to

[0059] of International Publication No. 2024 / 241820, etc. In the aforementioned specific examples, the photoacid generator of the arene sulfonate type or alkane sulfonate type is ideal because it produces an acid of moderate strength that can deprotect the acid-unstable group of the repeating unit B2.

[1127] The aforementioned photoacid generators may also include salt compounds containing anions with the structures shown below, but are not limited to these.

[1128] [Chemistry 383]

[1129]

[1130] [Chem. 384]

[1131]

[1132] [Chem.385]

[1133]

[1134] [Chemistry 386]

[1135]

[1136] [Chemistry 387]

[1137]

[1138] [Chem.388]

[1139]

[1140] (F) Among other photoacid generating agents, the cation paired with the aforementioned anion is preferably a sulfonium cation or a monazine cation. Specific examples of the aforementioned sulfonium cations may be the same as those shown in formula (Z-1) and formula (Z-3), but are not limited to these. Specific examples of the aforementioned monazine cations may be the same as those shown in formula (Z-2), but are not limited to these.

[1141] For the acids produced by the aforementioned photoacid generators, a pKa of -2.0 or higher is ideal, and -1.0 or higher is even more desirable. Furthermore, an upper limit of 2.0 for the pKa is preferred. The pKa values ​​were calculated using the pKa database in ACD / Chemsketch ver: 9.04, software developed by Advanced Chemistry Development, Inc.

[1142] When the chemically amplified positive resist composition of the present invention includes (F) other photoacid generating agents, their content is preferably 1 to 10 parts by mass relative to 80 parts by mass of the aforementioned (A) base polymer, and more preferably 1 to 5 parts by mass. By including other photoacid generating agents, the amount of acid generated in the exposed area and the solubility inhibition of the unexposed area can be appropriately adjusted. (F) Other photoacid generating agents can be used alone or in combination of two or more.

[1143] [(G) surfactant]

[1144] In order to improve the coating properties of the chemically amplified positive resist composition of the present invention, it may also contain a conventional surfactant as component (G). Several such surfactants are known, as described in International Publication No. 2006 / 121096, Japanese Patent Application Publication No. 2008-102383, Japanese Patent Application Publication No. 2008-304590, Japanese Patent Application Publication No. 2004-115630, and Japanese Patent Application Publication No. 2005-8766, and may be selected by referring to them.

[1145] When the chemically amplified positive resist composition of the present invention contains a surfactant (G), its content is preferably 2 parts by mass or less, more preferably 1 part by mass or less, relative to 80 parts by mass of the base polymer (A), and preferably 0.01 parts by mass or more. The surfactant (G) can be used alone or in combination of two or more.

[1146] [Resist Pattern Formation Method]

[1147] The resist pattern forming method of the present invention includes the following steps: forming a resist film on a substrate using the aforementioned chemically amplified positive resist composition, irradiating the aforementioned resist film with high-energy rays to form a pattern (i.e., exposing the aforementioned resist film with high-energy rays), and developing the aforementioned irradiated resist film with an alkaline developer to obtain a resist pattern.

[1148] The aforementioned substrate can be, for example, a substrate used for integrated circuit manufacturing (Si, SiO, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective film, etc.) or a substrate used for mask circuit manufacturing (Cr, CrO, CrON, MoSi2, Si, SiO, SiO2, etc.). The aforementioned chemically amplified positive resist composition is coated onto the substrate using methods such as spin coating to achieve a film thickness of 0.03~2 μm. The substrate is then pre-baked on a hot plate, preferably at 60~150°C for 1~20 minutes, more preferably at 80~140°C for 1~10 minutes, to form a resist film.

[1149] Next, high-energy rays are used to expose the aforementioned resist film and irradiate the pattern. Examples of such high-energy rays include ultraviolet light, far-ultraviolet light, excimer lasers (KrF, ArF, etc.), EB, EUV, X-rays, gamma rays, and synchrotron radiation.

[1150] When using ultraviolet light, far ultraviolet light, excimer lasers, EUV, X-rays, gamma rays, or synchrotron radiation to generate high-energy rays, a mask is used to form the desired pattern, with the optimal exposure dose being 1–300 mJ / cm². 2 The optimal value is 10~200mJ / cm. 2 Irradiation is performed in a manner that allows for optimal exposure of 1~300 μC / cm². When using EB (exposed beams) for high-energy radiation, the optimal exposure level is 1~300 μC / cm². 2 The optimal value is 10~200μC / cm. 2 The method of direct depiction. Furthermore, the chemically amplified positive resist composition of the present invention is particularly useful in EUV or EB lithography.

[1151] In addition to the usual exposure method, depending on the situation, an immersion method can also be used, in which a liquid is inserted between the mask and the resist film. In this case, a water-insoluble protective film can also be used.

[1152] Secondly, the product is exposed to heat and baked (PEB) on a hot plate, preferably at 60-150°C for 1-20 minutes, and more preferably at 80-140°C for 1-10 minutes.

[1153] Subsequently, a developer solution of alkaline aqueous solution such as 0.1-5% by mass, more preferably 2-3% by mass TMAH aqueous solution, is used to develop the substrate using conventional methods such as dip method, puddle method, and spray method for 0.1-3 minutes, preferably 0.5-2 minutes, thereby forming the desired pattern on the substrate.

[1154] The chemically amplified positive resist composition of the present invention exhibits particularly high etch resistance and minimal change in pattern linewidth even after exposure and prolonged PEB time, making it useful when low LER (Low Etching Rate) is required. Furthermore, the chemically amplified positive resist composition of the present invention is particularly useful when used on substrates made of materials where it is difficult to achieve good adhesion of the resist pattern on the surface, thus making pattern peeling and pattern collapse prone to occur. Examples of such substrates include substrates sputtered from metallic chromium or chromium compounds containing one or more light elements selected from oxygen, nitrogen, and carbon. The chemically amplified positive resist composition of the present invention is particularly useful when pattern formation is performed using a blank photomask as the substrate.

[1155] [Example]

[1156] The following examples, embodiments, and comparative examples are provided to specifically illustrate the present invention, but the present invention is not limited to the following embodiments. Furthermore, the apparatus used is shown below.

[1157] •IR: NICOLET 6700, Thermofisher Scientific

[1158] · 1 H-NMR: ECA-500 manufactured by Nippon Electronics Co., Ltd.

[1159] MALDI TOF-MS: S3000 manufactured by Nippon Electronics Co., Ltd.

[1160] [1] Synthesis of onium salts

[1161] [Synthetic Example 1-1] Synthesis of onium salt PAG-1

[1162] [Chemistry 389]

[1163]

[1164] (1) Synthesis of onium salt PAG-1

[1165] Under nitrogen atmosphere, 8.7 g of starting material SM-1, 30.5 g of an aqueous solution of starting material SM-2 (equivalent to 25.1 mol), and 50 g of dichloromethane were added to a reaction vessel. After stirring for 15 minutes, the organic layer was separated and washed with water, followed by concentration under reduced pressure. 50 g of methyl isobutyl ketone was added to the concentrate for azeotropic dehydration, followed by the addition of diisopropyl ether and crystallization, yielding 16.7 g of the target compound PAG-1 as white crystals (95% yield).

[1166] The IR spectral data and TOF-MS results of PAG-1 are shown below.

[1167] IR(D-ATR): ν= 3067, 2965, 2870, 1606, 1585, 1505, 1468, 1439, 1376,1327, 1273, 1229, 1206, 1124, 1061, 1017, 1003, 927, 889, 856, 833, 758, 706,667, 608, 557, 534, 494, 481, 437 cm -1 .

[1168] MALDI TOF-MS: POSITIVE M + 277 (equivalent to C) 18 H 13 OS + )

[1169] NEGATIVE M - 679 (equivalent to C) 42 H 47 O6S - )

[1170] [Synthetic Examples 1-2 to 1-10] Synthesis of Onium Salts PAG-2 to PAG-10

[1171] Using the corresponding raw materials and known organic synthesis reactions, onium salts PAG-2 to PAG-10 represented by the following formulas were synthesized.

[1172] [Chemistry 390]

[1173]

[1174] [Chemistry 391]

[1175]

[1176] [Comparative Synthesis Examples 1-1 to 1-5] Comparison of the synthesis using ononium salts PAG-A to PAG-E

[1177] Using the corresponding raw materials and known organic synthesis reactions, the comparative onium salts PAG-A to PAG-E represented by the following formulas were synthesized.

[1178] [Chemistry 392]

[1179]

[1180] [2] Polymer synthesis

[1181] The monomers used in the synthesis of the polymer are shown below.

[1182] [Chemistry 393]

[1183]

[1184] [Chemistry 394]

[1185]

[1186] [Chemistry 395]

[1187]

[1188] [Chemistry 396]

[1189]

[1190] [Chemistry 397]

[1191]

[1192] [Chem.398]

[1193]

[1194] [Chemistry 399]

[1195]

[1196] [Synthetic Example 2-1] Synthesis of Polymer P-1

[1197] Under nitrogen atmosphere, monomer A-1 (45.1 g), monomer B-1 (54.9 g), V-601 (manufactured by Fujifilm and Koei Tecmo Chemicals Co., Ltd.) 7.52 g, and PGMEA (propylene glycol monomethyl ether acetate) 139 g were charged into a flask to prepare a monomer-polymerization initiator solution. In another flask under nitrogen atmosphere, 46 g of PGMEA was charged, and the mixture was heated to 80°C with stirring. The aforementioned monomer-polymerization initiator solution was then added dropwise over 4 hours. After the addition was complete, the temperature of the polymerization solution was maintained at 80°C, and stirring continued for 2 hours, followed by cooling to room temperature. The obtained polymerization solution was added dropwise to 3000 g of vigorously stirred hexane, and the precipitated polymer was separated by filtration. The obtained polymer was washed twice with 600 g of hexane and then vacuum dried at 50°C for 20 hours to obtain a white powdered polymer P-1 (yield 81.1 g, 81% yield). The Mw of polymer P-1 is 5700, and the Mw / Mn ratio is 1.41. Furthermore, Mw is a polystyrene conversion value obtained using GPC with THF as the solvent.

[1198] [Chemical 400]

[1199]

[1200] [Synthetic Examples 2-2~2-54, Comparative Synthetic Examples 2-1~2-25] Synthesis of polymers P-2~P-54 and comparative polymers CP-1~CP-25

[1201] By changing the types and blending ratios of the monomers, polymers P-2 to P-54 shown in Tables 1 and 2, and comparative polymers CP-1 to CP-25 shown in Table 3, were synthesized using the same method as in Synthesis Example 2-1. Furthermore, in Tables 1-3, the incorporation rate is in mol%.

[1202] [Table 1]

[1203]

[1204] [Table 2]

[1205]

[1206] [Table 3]

[1207]

[1208] The dissolution rate of the aforementioned polymers to alkaline developer was calculated by spin-coating a polymer solution (polymer concentration: 16.7% by mass, solvent: PGME) onto an 8-inch silicon wafer, baking it at 100°C for 90 seconds to form a 1000 nm thick film, and then developing it with a 2.38% by mass TMAH aqueous solution at 23°C for 100 seconds, measuring the film loss. The results showed that the dissolution rate of polymers P-1 to P-54 was less than 10 nm / min. Furthermore, the dissolution rate of polymers CP-1 to CP-25 was also less than 10 nm / min.

[1209] [3] Preparation of chemically amplified positive resist composition

[1210] [Examples 1-1 to 1-90, Comparative Examples 1-1 to 1-60]

[1211] The components are dissolved in an organic solvent according to the compositions shown in Lists 4-7. The resulting solution is filtered through a nylon filter with a size of 5 nm and a UPE filter with a size of 1 nm, thereby preparing a chemically amplified positive resist composition. The aforementioned organic solvent is a mixture of 940 parts by weight of PGMEA, 1870 parts by weight of EL, and 1870 parts by weight of PGME.

[1212] [Table 4]

[1213]

[1214] [Table 5]

[1215]

[1216] [Table 6]

[1217]

[1218] [Table 7]

[1219]

[1220] Furthermore, Tables 4-7 show the following photoacid generators PAG-Y and PAG-Z, quenchers SQ-1 to SQ-4, and polymers FP-1 to FP-5 containing fluorine atoms.

[1221] [Chemical Engineering 401]

[1222]

[1223] [Chemical 402]

[1224]

[1225] [Chemical 403]

[1226]

[1227] [4] Evaluation of EB lithography

[1228] [Examples 2-1 to 2-90, Comparative Examples 2-1 to 2-60]

[1229] Various chemically amplified positive resist compositions (R-1~R-90, CR-1~CR-60) were spin-coated onto a 152 mm² EUV exposure mask with a chromium compound outermost surface using an ACT-M spin-coating machine. The mask was then pre-baked at 110°C for 600 seconds on a heated plate to produce a resist film with a thickness of 80 nm. The thickness of the obtained resist film was measured using an optical measuring instrument, Nanospec (Nanometrics). Measurements were taken at 81 points within the plane of the blank substrate, excluding the outer perimeter to the inner 10 mm area, and the average and range of the film thickness were calculated.

[1230] Then, exposure was performed using an electron beam lithography apparatus (EBM-5000plus manufactured by Nuflare Technology Co., Ltd., accelerating voltage 50kV), with PEB applied at 110°C for 600 seconds, followed by development with a 2.38% by mass TMAH aqueous solution to obtain a positive pattern. The obtained resist pattern was evaluated as follows.

[1231] The patterned blank mask was observed using an overhead SEM (scanning electron microscope). The optimal exposure (μC / cm) was defined as the 1:1 line-to-space ratio (LS) at 200 nm with a 1:1 resolution. 2 The limit resolution (LER) of a 200nm line spacing (LS) with a 1:1 exposure ratio is defined as the minimum size of the LS at a 1:1 resolution. The LER of the 200nm LS is measured by SEM. For the limit resolution of isolation spacing (IS), the minimum size of the 200nm 9:1 line spacing (LS) with a 9:1 exposure ratio is defined as the limit IS resolution.

[1232] Furthermore, for an LS pattern with a linewidth of 18nm and a pitch of 36nm formed using the aforementioned optimal exposure, a defect inspection device KLA2360 (trade name) manufactured by KLA TENCOR was used. The pixel size of the defect inspection device was set to 0.16μm and the threshold to 20. Defects (number / cm) extracted from the differences caused by the overlap of the comparison image and pixel units were detected. 2 ), calculate the number of defects per unit area (defects / cm²) 2Next, a defect review is conducted, and developing defects are classified and extracted from all defects to calculate the number of developing defects per unit area (defects / cm²). 2 Values ​​below 0.5 are rated A, values ​​above 0.5 but below 1.0 are rated B, values ​​above 1.0 but below 5.0 are rated C, and values ​​above 5.0 are rated D. Lower values ​​indicate better performance. Results are shown in Tables 8-11.

[1233] [Table 8]

[1234]

[1235] [Table 9]

[1236]

[1237] [Table 10]

[1238]

[1239] [Table 11]

[1240]

[1241] The chemically amplified positive resist compositions (R-1 to R-90) of the present invention all exhibit good resolution and LER, and few development defects have been confirmed. On the other hand, the resist compositions of the comparative examples (CR-1 to CR-60) have unsatisfactory acid diffusion optimization and contrast, and deterioration was observed in resolution, LER, and development defects.

[1242] The resist patterning method using the chemically amplified positive resist composition of the present invention is useful in optical lithography in the manufacture of semiconductor devices, especially in the processing of transmissive and reflective blank photomasks.

Claims

1. A chemically amplified positive resist composition comprising (A) a base polymer, a polymer containing repeating units represented by formula (A1) and exhibiting increased solubility in alkaline aqueous solutions due to acid action, and (B) a photoacid generator consisting of an onium salt represented by formula (B). In the formula, a1 is 0 or 1, and a2 is 0, 1, 2 or 3 when a1 is 0, and 0, 1, 2, 3, 4 or 5 when a1 is 1. R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. X 1 It is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-, where * indicates an atomic bond with a carbon atom in the main chain. X 2 A single bond, an aliphatic alkylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a combination thereof. X 3 and X 4 Each can be independently an oxygen atom or a sulfur atom, but X 2 and X 4 Bonded to adjacent carbon atoms of the aromatic ring, R 1 and R 2 Each is an independent hydrocarbon group consisting of hydrogen atoms, or may contain heteroatoms, and has 1 to 20 carbon atoms. Also, R 1 and R 2 They can also bond to each other and form rings together with the carbon atoms they are bonded to. R 3 It can be a halogen atom, hydroxyl group, cyano group, nitro group, pentafluorothio group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxygen group with 2 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms or -N(R) group. 3A (R) 3B ), R 3A and R 3B Each is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; when a2 is 2 or more, each R 3 They can be the same or different, multiple Rs 3 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. In the formula, n1 is 0 or 1, n2 is 0, 1, 2, 3 or 4, and n3 is 2, 3 or 4. However, when n1 is 0, 2 ≤ n2 + n3 ≤ 5, and when n1 is 1, 2 ≤ n2 + n3 ≤ 7. R 101 The radical can be a halogen atom, nitro, cyano, hydroxyl, carboxyl, or a hydrocarbon group with 1-20 carbon atoms containing heteroatoms; it can also be a hydrocarbon oxy group with 1-20 carbon atoms containing heteroatoms; it can also be a hydrocarbon thio group with 1-20 carbon atoms containing heteroatoms; or it can be a hydrocarbon oxycarbonyl group with 1-20 carbon atoms containing heteroatoms. When n2 is 2, 3, or 4, each R... 101 They can be the same or different, multiple Rs 101 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Z + It is a ium cation. Ar AL The group represented by the formula (AL) contains an acid-labile group, but with at least one Ar group. AL and -SO3 - The bonded carbon atoms are adjacent carbon atoms. In the formula, n4 is 0 or 1, n5 is 0, 1, 2, 3 or 4, n6 is 0, 1, 2, 3 or 4, and n7 is 1 or 2. However, when n4 is 0, the formula is 1 ≤ n5 + n6 + n7 ≤ 5, and when n4 is 1, the formula is 1 ≤ n5 + n6 + n7 ≤ 7. R 102 The radical can be a halogen atom other than fluorine, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon oxy group with 1 to 20 carbon atoms containing heteroatoms; it can also be a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms; or it can be a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms containing heteroatoms. When n5 is 2, 3, or 4, each R... 102 They can be the same or different, multiple Rs 102 They can also bond to each other and form rings together with the carbon atoms they are bonded to. R F When n6 is 2, 3, or 4, each R... F They can be the same or different. R L1 and R L2 Each is an independent hydrocarbon group having 1 to 12 carbon atoms, R L3 R is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. L1 R L2 and R L3 The -CH2- group of the hydrocarbon group may also be partially replaced by -O- or -S-. When the hydrocarbon group contains an aromatic ring or multiple bonds, part or all of the hydrogen atoms bonded to the carbon atoms constituting the aromatic ring or multiple bonds may also be replaced by halogen atoms, cyano groups, nitro groups, alkyl groups with 1 to 4 carbon atoms that may contain halogen atoms, or alkoxy groups with 1 to 4 carbon atoms that may contain halogen atoms. Furthermore, R... L1 and R L2 They can also bond to each other and form a ring together with the carbon atoms they are bonded to. A portion of the -CH2- in this ring can be replaced by -O- or -S-, but R... L3 When the alicyclic structure, aromatic ring, and multiple bonds are all absent, R L1 and R L2 They bond to each other and together with the carbon atoms they are bonded to form a ring. Part of the -CH2- in this ring can also be replaced by -O- or -S-. * indicates an atomic bond.

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

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

4. The chemically amplified positive resist composition according to claim 1, wherein, The photoacid generator is represented by the following formula (B1). In the formula, n1, n2, n3, n5, n6, n7, R 101 R 102 R F R L1 ~R L3 and Z + As mentioned above.

5. The chemically amplified positive resist composition according to claim 4, wherein, The photoacid generator is represented by the following formula (B2). In the formula, n2, n3, n5, n6, n7, R 101 R 102 R F R L1 ~R L3 and Z + As mentioned above.

6. The chemically amplified positive resist composition according to claim 1, wherein, Z + The sulfonium cation is represented by formula (Z-1) or the monazine cation is represented by formula (Z-2). In the formula, R ct1 ~R ct5 Each is an independent halogen atom, or may contain heteroatoms, of a hydrocarbon group having 1 to 30 carbon atoms; also, R ct1 and R ct2 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

7. The chemically amplified positive resist composition according to claim 1, wherein, Z + The sulfonium cation is represented by the following formula (Z-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, but m1 is... When m1 is 1, it is 0 ≤ m6 + m9 ≤ 4; when m2 is 0, it is 0 ≤ m6 + m9 ≤ 6; when m2 is 0, it is 0 ≤ m7 + m10 ≤ 4; when m2 is 1, it is 0 ≤ m7 + m10 ≤ 6; when m3 is 0, it is 1 ≤ m4 + m5 + m8 + m14 ≤ 4; when m3 is 1, it is 1 ≤ m4 + m5 + m8 + m14 ≤ 6; when m11 is 0, it is 0 ≤ m12 + m13 ≤ 4; when m11 is 1, it is 0 ≤ m12 + m13 ≤ 6; and m4 + m12 ≥ 1. R F1 ~R F3 Each of the following is independently a fluorine atom, a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, a fluorinated saturated hydrocarbon oxygen group having 1 to 6 carbon atoms, or a fluorinated saturated hydrocarbon thio group having 1 to 6 carbon atoms. When m5 is 2, 3, or 4, each R F1 They can be the same or different. When m6 is 2, 3, 4, 5 or 6, each R... F2 They can be the same or different. When m7 is 2, 3, 4, 5 or 6, each R... F3 They can be the same or different. R ct6 ~R ct9 The radical can be a halogen atom other than iodine and fluorine, a nitro group, a cyano group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms. When m8 is 2, there are 2 R radicals. ct6 They can be the same or different, 2 Rs ct6 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m9 is 2, there are 2 R atoms. ct7 They can be the same or different, 2 Rs ct7 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m10 is 2, there are 2 R atoms. ct8 They can be the same or different, 2 Rs ct8 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m13 is 2, there are 2 R atoms. ct9 They can be the same or different, 2 Rs ct9 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Furthermore, the sum of S in sulfonium cations + Directly bonded aromatic rings can also bond to each other and with S + Together they form a ring. L A and L B Each bond can be independently a single bond, ether bond, ester bond, amide bond, sulfonate bond, sulfonamide bond, carbonate bond, or carbamate bond. X L It can be a single bond, or it can also contain a heteroatom with 1 to 40 carbon atoms and a hydrocarbon group.

8. The chemically amplified positive resist composition according to claim 1, wherein, The polymer also contains repeating units represented by the following formula (A2), In the formula, b1 is 0, 1, or 2; b2 is 1, 2, or 3; and b3 is an integer satisfying 0 ≤ b3 ≤ 5 + 2(b1) - b2. R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Y 1 It is a single bond, *-C(=O)-O- or *-C(=O)-N(H)-, where * indicates an atomic bond with a carbon atom in the main chain. R 11 It can be a halogen atom, a nitro group, a carboxyl group, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, a 1-6 carbon saturated hydrocarbon oxygen group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom. A 1 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

9. The chemically amplified positive resist composition according to claim 1, wherein, The polymer contains at least one repeating unit selected from the repeating units represented by formula (A3), formula (A4), and formula (A5). In the formula, c is 0, 1, 2, 3, 4, 5, or 6; d is 0, 1, 2, 3, or 4; e1 is 0 or 1; e2 is 0, 1, or 2; and e3 is 0, 1, 2, 3, 4, or 5. R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 21 and R 22 Each can be independently a hydroxyl group, a halogen atom, a 1-8 carbon saturated hydrocarbon group that can be substituted with a halogen atom, a 1-8 carbon saturated hydrocarbon oxygen group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom. R 23 It can be a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxygen group with 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl group with 2 to 20 carbon atoms, a saturated hydrocarbon sulfide group with 2 to 20 carbon atoms, a halogen atom, a nitro group, or a cyano group. When e3 is 1 or 2, it can also be a hydroxyl group. A 2 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of the saturated hydrocarbon group can also be replaced by -O-.

10. The chemically amplified positive resist composition according to claim 1, wherein, The polymer also contains at least one repeating unit selected from the repeating units represented by formula (A6-1) and formula (A6-2). In the formula, f1 is 0 or 1, f2 is 0, 1 or 2, f3 is an integer satisfying 0 ≤ f3 ≤ 5 + 2(f2) - f4, f4 is 1, 2 or 3, and f5 is 0 or 1. f11 is 0, 1, or 2; f12 is 0, 1, or 2; f13 is 0, 1, or 2; f14 is 0, 1, 2, 3, 4, or 5. R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. A 3 It is a single bond or a saturated hydrocarbon group with 1 to 10 carbon atoms, and part of the -CH2- of this saturated hydrocarbon group may also be replaced by -O-. A 4 It is a single bond, phenylene, naphthylene, or *-C(=O)-OA 41 -, A 41 It may also contain an aliphatic alkylene group, or a phenylene or naphthylene group, with 1 to 20 carbon atoms, and may also contain a hydroxyl group, ether bond, ester bond, or lactone ring. * indicates an atomic bond with a carbon atom in the main chain. R 31 It can be a halogen atom, or a 1-6 carbon saturated hydrocarbon group that can be substituted with a halogen atom, or a 2-8 carbon saturated hydrocarbon carbonyl group that can be substituted with a halogen atom. R 32 and R 33 Each can be independently a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. 32 and R 33 They can also bond to each other and form rings together with the carbon atoms they are bonded to. R 34 Each is independently a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkoxy group having 1 to 5 carbon atoms. R 35 Each can independently be a hydrocarbon group with 1 to 10 carbon atoms, which may also contain heteroatoms. When X is 1 in f4, it is an acid-labile group; when X is 2 or 3 in f4, it is a hydrogen atom or an acid-labile group, but at least one of them is an acid-labile group.

11. The chemically amplified positive resist composition according to claim 1, wherein, The polymer contains at least one repeating unit selected from the following formula (A7), the following formula (A8), the following formula (A9), the following formula (A10), and the following formula (A11). In the formula, g1 and g2 are each independently 0, 1, 2, or 3; h1 is 0 or 1; h2 is 0, 1, 2, 3, or 4; and h3 is 0, 1, 2, 3, or 4. However, when h1 is 0, 0 ≤ h2 + h3 ≤ 4; and when h1 is 1, 0 ≤ h2 + h3 ≤ 6. R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z 1 It can be a single bond or may have substituents, phenylene Z 2 For single bonds, **-C(=O)-OZ 21 -、**-C(=O)-N(H)-Z 21 -or**-OZ 21 -, Z 21 It is a divalent group obtained by aliphatic hydrocarbon groups, phenylene groups, or combinations thereof having 1 to 6 carbon atoms, and may also contain halogen atoms, carbonyl groups, ester bonds, ether bonds, or hydroxyl groups. Z 3 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, amide bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Z 4 It is a divalent group obtained by a single bond, or an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, or a combination thereof, and may also contain a halogen atom, a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. Z 5 Each can be a single bond, or a phenylene group with substituents, or a naphthylene group with substituents, *-C(=O)-OZ 51 -or *-C(=O)-N(R)-Z 51 -, Z 51 It is an aliphatic hydrocarbon group, phenylene, or naphthylene with 1 to 10 carbon atoms. This aliphatic hydrocarbon group may also contain a halogen atom, hydroxyl group, ether bond, ester bond, or lactone ring. R is a hydrogen atom, or it may also be a hydrocarbon group with 1 to 10 carbon atoms containing heteroatoms. Z 6 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, amide bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Z 7 Each is independently a single bond, ***-Z 71 -C(=O)-O-、***-C(=O)-N(R)-Z 71 -or ***-OZ 71 -, Z 71 It can also contain a hydrocarbon group with 1 to 20 carbon atoms, R as described above. Z 8 Each is independently a single key, ****-Z 81 -C(=O)-O-、****-C(=O)-N(R)-Z 81 -or ****-OZ 81 -, Z 81 It can also contain a hydrocarbon group with 1 to 20 carbon atoms, R as described above. Z 9 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, trifluoromethyl-substituted phenylene, *-C(=O)-OZ 91 -、*-C(=O)-N(R)-Z 91 -or *-OZ 91 -, Z 91 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or trifluoromethyl-substituted phenylene, having 1 to 6 carbon atoms. It may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group, R as described above. * indicates an atomic bond with a carbon atom in the main chain, ** indicates an atomic bond with a Z atom. 1 atomic bonds, *** represents the bond between Z and Z 6 atomic bonds, **** represents the bond between Z and 7 atomic bonds, L 1 The bonds can be single bonds, ether bonds, ester bonds, carbonyl groups, sulfonate bonds, sulfonamide bonds, carbonate bonds, or carbamate bonds. Rf 1 and Rf 2 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Rf 3 and Rf 4 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Rf 5 and Rf 6 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms, but all Rf 5 and Rf 6 They are not both hydrogen atoms. Rf 7 When h2 is 2, 3, or 4, each Rf is a fluorine atom, a fluorinated alkyl group having 1 to 6 carbon atoms, a fluorinated alkoxy group having 1 to 6 carbon atoms, a fluorinated alkyl thio group having 1 to 6 carbon atoms, or a pentafluorothio group. 7 They can be the same or different. R 41 and R 42 Each can independently be a hydrocarbon group with 1 to 20 carbon atoms, which may also contain heteroatoms. Also, R 41 and R 42 They can also bond to each other and form rings together with the sulfur atoms they are bonded to. R 43 When h3 is 2, 3, or 4, each R... 43 They can be the same or different, multiple Rs 43 They can also bond to each other and form rings together with the carbon atoms they are bonded to. M - It is a non-nucleophilic relative ion. A + It is a ium cation.

12. The chemically amplified positive resist composition according to claim 1, wherein, Of all the repeating units in the base polymer, the content of repeating units with an aromatic ring skeleton is more than 60 mol%.

13. The chemically amplified positive resist composition according to claim 1, further comprising (C) an organic solvent.

14. The chemically amplified positive resist composition according to claim 1, further comprising (D) a quencher.

15. The chemically amplified positive resist composition according to claim 1, further comprising a polymer containing fluorine atoms, the polymer containing fluorine atoms containing at least one repeating unit selected from the following formula (E1), the following formula (E2), the following formula (E3), and the following formula (E4), and may also further contain at least one repeating unit selected from the following formula (E5) and the following formula (E6). 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; and k is 1, 2, or 3. R B Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R C Each can be independently a hydrogen atom or a methyl group. R 301 R 302 R 304 and R 305 Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. R 303 R 306 R 307 and R 308 Each is independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-labile group, R 303 R 306 R 307 and R 308 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group may also be inserted between the carbon-carbon bonds. R 309 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, consisting of hydrogen atoms or groups containing heteroatoms inserted between carbon-carbon bonds; when j1 is 2 or 3, each R 309 They can be the same or different. R 310 A straight-chain or branched hydrocarbon group with 1 to 5 carbon atoms, in which heteroatoms may be inserted between carbon-carbon bonds; when j2 is 2 or more, each R 310 They can be the same or different. R 311 A saturated hydrocarbon group with 1 to 20 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom. A portion of the -CH2- group of this saturated hydrocarbon group may also be replaced by an ester or ether bond. W 1 It is a (k+1) valence hydrocarbon group with 1 to 20 carbon atoms or a (k+1) valence fluorinated hydrocarbon group with 1 to 20 carbon atoms. W 2 These are single bonds, *-C(=O)-O-, or *-C(=O)-N(H)-, where * represents an atomic bond with a carbon atom in the main chain. W 3 For single bonds, -O-, *-C(=O)-OW 31 -W 32 -or *-C(=O)-N(H)-W 31 -W 32 -, W 31 W is a single bond or a saturated alkylene group with 1 to 10 carbon atoms. 32 It is a single bond, ester bond, ether bond, or sulfonamide bond, and * is an atomic bond with a carbon atom in the main chain.

16. The chemically amplified positive resist composition according to claim 1, further comprising a photoacid generator other than an onium salt represented by formula (B).

17. A method for forming a resist pattern, comprising the following steps: A resist film is formed on a substrate using the chemically amplified positive resist composition according to any one of claims 1 to 16, and a pattern is irradiated onto the resist film using high-energy rays. The resist film of the irradiated pattern was developed using an alkaline developer.

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

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

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

Images