Sulfonium salt type monomer, polymer, chemically amplified resist composition, and pattern forming method

Abstract

The invention relates to a sulfonium salt type monomer, a polymer, a chemically amplified resist composition and a pattern forming method. The present invention addresses the problem of providing a photolithographic film having excellent solvent solubility, high sensitivity, high contrast, and excellent photolithographic properties during optical lithography using high-energy rays. The present invention relates to a sulfonium salt-type monomer used in a chemically amplified resist composition having excellent photolithography properties such as EL, LWR, CDU, and DOF, a polymer containing a repeating unit derived from the sulfonium salt-type monomer, a chemically amplified resist composition containing the polymer, and a pattern forming method using the chemically amplified resist composition. [Solution] A sulfonium salt-type monomer represented by formula (A).

Description

TECHNICAL FIELD

[0001] The present application relates to a sulfonium salt type monomer, a polymer, a chemically amplified resist composition, and a pattern forming method. BACKGROUND

[0002] With the high integration and high speed of LSI, the miniaturization of pattern rules is rapidly progressing. In particular, the expansion of the flash memory market and the increase in memory capacity lead to miniaturization. In the most advanced miniaturization technology, mass production of 65 nm node devices using ArF lithography is being carried out, and mass production of 45 nm node devices using the next-generation ArF immersion lithography is being prepared. For the next-generation 32 nm node devices, immersion lithography using a super-NA lens composed of a liquid with a higher refractive index than water, a high-refractive-index lens, and a high-refractive-index resist film, extreme ultraviolet (EUV) lithography with a wavelength of 13.5 nm, double exposure (double patterning lithography) of ArF lithography, and the like are candidates, and are being discussed.

[0003] As the miniaturization proceeds, the contrast of light decreases as the diffraction limit of light is approached. Due to the decrease in the contrast of light, the resolution of hole patterns and trench patterns, and the focus margin in positive resist films decrease.

[0004] With the miniaturization of patterns, the edge roughness (LWR) of line patterns and the size uniformity (CDU) of hole patterns are considered to be problems. The influence of the uneven distribution of base polymers and acid generators, the influence of aggregation, and the influence of acid diffusion have been pointed out. Then, there is a tendency for LWR to increase due to the thinning of resist films, and the degradation of LWR due to the thinning accompanying the progress of miniaturization has become a serious problem.

[0005] In resist compositions for EUV lithography, high sensitivity, high resolution, and low LWR must be achieved at the same time. If the acid diffusion distance is shortened, LWR will be smaller but sensitivity will be lower. For example, LWR will be smaller by lowering the post-exposure bake (PEB) temperature, but sensitivity will be lower. Increasing the amount of quencher added will also make LWR smaller, but sensitivity will also be lower. The trade-off relationship between sensitivity and LWR must be broken.

[0006] To suppress acid diffusion, resist compounds containing repeating units from onium salts of sulfonic acids with polymerizable unsaturated bonds have been proposed (Patent Document 1). Such polymer-bonded acid generators are characterized by the generation of polymeric sulfonic acids upon exposure, resulting in very short acid diffusion. Furthermore, sensitivity can be improved by increasing the proportion of the acid generator. In the case of additive acid generators, increasing the amount added also increases sensitivity, but at the same time, the acid diffusion distance also increases. Because acid diffuses unevenly, increased acid diffusion degrades LWR and CDU. In terms of balancing sensitivity, LWR, and CDU, polymer-bonded acid generators can be considered to have high capability.

[0007] Iodine atoms exhibit very high absorption at a wavelength of 13.5 nm in EUV, confirming the generation of secondary electrons from iodine atoms during exposure, a phenomenon that has attracted attention in EUV lithography. Patent Document 2 describes a photoacid generator in which iodine atoms are introduced into the anion, and Patent Document 3 describes a photoacid generator containing polymerizable groups in which iodine atoms are introduced into the anion. While this confirms some improvement in lithography performance, the low solubility of iodine atoms in organic solvents poses a risk of precipitation in the solvent.

[0008] Patent documents 4 and 5 describe photoacid generators in which pentafluorosulfide (-SF5) and trifluoromethoxy (-OCF3) groups are introduced into the cation. While this has led to some progress in improving photolithography performance, there is still room for improvement, requiring the development of more effective resist materials for fine pattern formation.

[0009] Existing technical documents

[0010] Patent documents

[0011] [Patent Document 1] Japanese Patent No. 4425776

[0012] [Patent Document 2] Japanese Patent No. 6720926

[0013] [Patent Document 3] Japanese Patent No. 6973274

[0014] [Patent Document 4] International Publication No. 2023 / 223624

[0015] [Patent Document 5] Japanese Patent Application Publication No. 2022-59112 Summary of the Invention

[0016] [The problem that the invention aims to solve]

[0017] The development of chemically amplified resist compositions that use acid as a catalyst requires the development of resist compositions with higher sensitivity and the ability to improve lithographic properties such as exposure margin (EL), light retardant (LWR), chromatic duct density (CDU), and depth of focus (DOF).

[0018] In view of the foregoing, the present invention aims to provide, in particular when using optical lithography with high-energy rays such as KrF excimer lasers, ArF excimer lasers, electron beams (EB), and EUV, a sulfonium salt monomer used in a chemically amplified resist composition, a polymer containing repeating units from the sulfonium salt monomer, a chemically amplified resist composition containing the polymer, and a patterning method using the chemically amplified resist composition, for use in optical lithography, especially when using high-energy rays such as KrF excimer lasers, ArF excimer lasers, electron beams (EB), and EUV.

[0019] [Methods for solving the problem]

[0020] The inventors of this application, through repeated and in-depth research to achieve the aforementioned objectives, discovered that by using a polymer containing repeating units of a sulfonate-type monomer derived from a sulfonate cation having a cyano group and a fluorosulfonic acid anion having an aromatic vinyl structure and an iodine atom, which serves as a polymer bonding acid generator, a chemically amplified resist composition with improved photolithography properties such as EL, LWR, CDU, and DOF, high contrast, and high resolution can be obtained, thus completing this invention.

[0021] That is, the present invention provides the following composition of sulfonium salt monomer, polymer, chemically amplified resist and pattern formation method.

[0022] 1. A sulfonium salt type monomer, represented by the following formula (A),

[0023] [Chemistry 1]

[0024]

[0025] In the formula, p is 1, 2, or 3; n1 is 0 or 1; n2 is 1 or 2; and n3 is 0, 1, 2, or 3. However, when n1 is 0, then 1 ≤ n2 + n3 ≤ 5; and when n1 is 1, then 1 ≤ n2 + n3 ≤ 7.

[0026] R 1 The R group can be a halogen atom, nitro group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms, a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms, a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms, or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When n3 is 2 or 3, each R group... 1 They can be the same or different, 2 Rs 1 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0027] R 2 The two R groups are halogen atoms or may contain heteroatoms and are hydrocarbon groups with 1 to 30 carbon atoms. When p is 1, the two R groups are... 2 They can be the same, or they can be different, and also, with S + Two of the three substituents in the bond can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

[0028] Z - It is a fluoroalkane sulfonic acid anion with an aromatic vinyl structure and an iodine atom.

[0029] 2. As in 1., the sulfonium salt type monomer is represented by the following formula (A1).

[0030] [Chemistry 2]

[0031]

[0032] In the formula, p, n1~n3, R 1 and Z - As mentioned above,

[0033] n4 is 0 or 1, n5 is 0, 1, 2, 3, 4 or 5.

[0034] R 3 The radical can be a halogen atom, nitro group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When n5 is 2, 3, 4, or 5, each R... 3 They can be the same or different, 2 Rs 3 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0035] 3. Sulfonate type monomers such as 1. or 2, wherein Z - Let Z represent the anion.

[0036] [Chemistry 3]

[0037]

[0038] In the formula, m1 is 0 or 1, m2 is 0, 1, 2, 3 or 4, m3 is 0, 1, 2 or 3, m4 is 0 or 1, m5 is 0, 1, 2, 3 or 4, m6 is 0, 1, 2 or 3, m7 is 0 or 1, m8 is 1, 2, 3 or 4, m9 is 0, 1, 2 or 3, m10 is 0, 1, 2, 3 or 4, m11 is 0 or 1, and m12 is 0 or 1. However, when m1 is 0, then 0 ≤ m2 + m3 + m12 ≤ 4; when m1 is 1, then 0 ≤ m2 + m3 + m12 ≤ 6; when m4 is 0, then 0 ≤ m5 + m6 ≤ 4; when m4 is 1, then 0 ≤ m5 + m6 ≤ 6; when m7 is 0, then 0 ≤ m8 + m9 ≤ 5; when m7 is 1, then 0 ≤ m8 + m9 ≤ 7. Also, 1 ≤ m2 + m5 + m8 ≤ 4.

[0039] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0040] R 11 R 12 and R 13 Each group can be independently composed of a halogen atom other than an iodine atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When m3 is 2 or 3, each R... 11 They can be the same or different, 2 Rs 11 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m6 is 2 or 3, each R 12 They can be the same or different, 2 Rs 12 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m9 is 2 or 3, each R 13 They can be the same or different, 2 Rs 13 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0041] L A L B L C L D and L E Each bond can be independently a single bond, ether bond, ester bond, sulfonate bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond.

[0042] X L1 and X L2 Each is an independent single bond, or may contain heteroatoms, consisting of 1 to 40 carbon-containing hydrocarbon groups.

[0043] Q 1 and Q 2 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms.

[0044] Q 3 and Q 4 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms.

[0045] However, m11 and m12 cannot both be 0 at the same time, L A L B L C L D X L1 and X L2 It cannot be a single key at the same time.

[0046] 4. A monomeric photoacid generator, comprising a sulfonium salt monomer as described in any one of 1 to 3.

[0047] 5. A polymer comprising repeating units from a monomeric photoacid generator as described in 4.

[0048] 6. The polymer as described in 5. further comprises at least one selected from the repeating unit represented by formula (a1), the repeating unit represented by formula (a2), and the repeating unit represented by formula (a3).

[0049] [Chemistry 4]

[0050]

[0051] In the formula, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0052] X 1 It is a single bond, phenylene, naphthylene, or *-C(=O)-OX 11 - The phenylene or naphthylene group may also be substituted with a hydroxyl, nitro, cyano group, a saturated hydrocarbon group containing fluorine atoms with 1 to 10 carbon atoms, a saturated hydroxyl group containing fluorine atoms with 1 to 10 carbon atoms, or a halogen atom. X 11 It is a saturated hydrocarbon group, phenylene group, or naphthylene group having 1 to 10 carbon atoms. The saturated hydrocarbon group may also contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring.

[0053] X 2 It is a single bond or *-C(=O)-O-.

[0054] * indicates an atomic bond with a carbon atom in the main chain.

[0055] R 21The R group can be a halogen atom, cyano group, hydroxyl group, nitro group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxygen group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When a1 is 2, 3, or 4, each R group... 21 They can be the same, or they can be different.

[0056] AL 1 and AL 2 Each is an independent acid-labile group.

[0057] a1 is 0, 1, 2, 3, or 4.

[0058] [Chemistry 5]

[0059]

[0060] In the formula, b1 is 0 or 1, and b2 is 0, 1, 2 or 3 when b1 is 0, and 0, 1, 2, 3, 4 or 5 when b1 is 1.

[0061] R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0062] X 3 These are single bonds, *-C(=O)-O-, or *-C(=O)-NH-, where * indicates an atomic bond with a carbon atom in the main chain.

[0063] X 4 It can be a single bond, an aliphatic alkylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a combination thereof.

[0064] X 5 and X 6 Each can be independently an oxygen atom or a sulfur atom, but X 4 and X 6 Bonded to adjacent carbon atoms in the aromatic ring,

[0065] R 22 and R 23 Each is an independent hydrocarbon group consisting of 1 to 20 carbon atoms, or may contain heteroatoms; and R 22 and R 23 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0066] R 24 It may contain halogen atoms, hydroxyl groups, cyano groups, nitro groups, or hydrocarbon groups with 1 to 20 carbon atoms that may contain heteroatoms; hydrocarbon oxygen groups with 1 to 20 carbon atoms that may contain heteroatoms; hydrocarbon oxygen carbonyl groups with 2 to 20 carbon atoms that may contain heteroatoms; or hydrocarbon thio groups with 1 to 20 carbon atoms or -N(R) groups.24A (R) 24B ), R 24A and R 24B Each is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; when b2 is 2 or more, each R 24 They can be the same or different; multiple Rs 24 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0067] 7. The polymer as described in 5. or 6. further comprises at least one repeating unit selected from the repeating units represented by formula (b1) and formula (b2).

[0068] [Chemistry 6]

[0069]

[0070] In the formula, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0071] Y 1 It represents a single bond or *-C(=O)-O-, where * indicates an atomic bond with a carbon atom in the main chain.

[0072] R 31 It is a hydrogen atom, or a group containing at least one carbon atom selected from hydroxyl groups other than phenolic hydroxyl groups, cyano groups, carbonyl groups, carboxyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, and carboxylic anhydrides (-C(=O)-OC(=O)-).

[0073] R 32 The R group can be a halogen atom, carboxyl group, nitro group, cyano group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxygen group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When c2 is 2, 3, or 4, each R group... 32 They can be the same, or they can be different.

[0074] c1 can be 1, 2, 3 or 4, and c2 can be 0, 1, 2, 3 or 4, but 1≤c1+c2≤5.

[0075] 8. A chemically amplified resist composition comprising (A) a base polymer containing a polymer as described in any one of 5 to 7.

[0076] 9. As in 8., the chemically amplified resist composition also contains (B) an organic solvent.

[0077] 10. Chemically amplified resist compositions such as 8 or 9, also contain (C) quenching agents.

[0078] 11. A chemically amplified resist composition as described in any of 8 to 10, further comprising (D) a photoacid generator.

[0079] 12. A chemically amplified resist composition as described in any of 8 to 11, further comprising (E) a surfactant.

[0080] 13. A method for forming a pattern, comprising the following steps:

[0081] A resist film is formed on a substrate using a chemically amplified resist composition as described in any of 8 to 12, the resist film is exposed to high-energy radiation, and the exposed resist film is developed using a developer.

[0082] 14. The pattern forming method as in 13, wherein the high-energy ray is a KrF excimer laser, an ArF excimer laser, an electron beam, or extreme ultraviolet light with a wavelength of 3 to 15 nm.

[0083] [The effects of the invention]

[0084] When patterning is performed using a chemically amplified resist composition containing repeating units of a polymer that function as a photoacid generator and contains sulfonium salt-type monomers from the present invention, high contrast and good sensitivity are achieved, and resist patterns with excellent photolithographic properties such as EL, LWR, CDU, and DOF can be formed. Detailed Implementation

[0085] 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 carbons, and thus mirror-image isomers and non-mirror-image isomers may exist. In such cases, a single formula is used to represent these isomers. These isomers may be used individually or as a mixture of two or more.

[0086] [Sulfonate type monomer]

[0087] The sulfonium salt type monomer of the present invention is represented by the following formula (A).

[0088] [Chemistry 7]

[0089]

[0090] In equation (A), p is 1, 2 or 3.

[0091] In formula (A), n1 is 0 or 1. When n1 is 0, it is a benzene ring; when n1 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with n1 of 0 is preferred. n2 is 1 or 2. Considering the availability of raw materials, n2 of 1 is preferred. n3 is 0, 1, 2, or 3. Considering the availability of raw materials, n3 of 0, 1, or 2 is preferred. However, when n1 is 0, then 1 ≤ n2 + n3 ≤ 5; when n1 is 1, then 1 ≤ n2 + n3 ≤ 7.

[0092] In formula (A), R 1 The halogen atom, nitro group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms, an alkyloxy group with 1 to 20 carbon atoms that may contain heteroatoms, an alkylthio group with 1 to 20 carbon atoms that may contain heteroatoms, or an alkyloxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. The hydrocarbon portion of the aforementioned hydrocarbon group, alkyloxy group, and alkylthio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, 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, norbornel, 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 these. Among these, aryl is preferred. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by heteroatom groups containing oxygen, sulfur, nitrogen, halogen atoms, etc., and a portion of the -CH2- group in the aforementioned hydrocarbon group can also be replaced by heteroatom groups containing oxygen, sulfur, nitrogen atoms, etc. As a result, it can also include hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonyl lactone ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. When n3 is 2 or 3, each R... 1 They can be the same or different. Also, when n3 is 2 or 3, multiple R... 1 They can also bond to each other and form rings together with the carbon atoms they are bonded to. The aforementioned rings are preferably 5- to 8-membered rings.

[0093] In formula (A), R 2 A hydrocarbon group consisting of 1 to 30 carbon atoms, which may also contain heteroatoms. When p is 1, there are 2 R groups. 2 They can be the same, or they can be different.

[0094] R 2 Specific examples of halogen atoms can be listed, such as fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0095] R 2 The hydrocarbon group represented can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norcamphenyl, and adamantyl; alkenyl groups with 2 to 30 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups with 3 to 30 carbon atoms such as cyclohexenyl; aryl groups with 6 to 30 carbon atoms such as phenyl, naphthyl, and thiophene; aralkyl groups with 7 to 30 carbon atoms such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining these, with aryl 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, 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.

[0096] Furthermore, the bond is to S + Two of the three substituents can also bond to each other and form a ring together with the sulfur atoms they are bonded to. In this case, specific examples of the aforementioned ring structure can be given by formulas such as the following.

[0097] [Chemistry 8]

[0098]

[0099] In the formula, the dashed lines represent atomic bonds.

[0100] The sulfonium salt type monomer represented by formula (A) should preferably be represented by the following formula (A1).

[0101] [Chemistry 9]

[0102]

[0103] In the formula, p, n1~n3 and R 1 Same as above. Z - To be discussed later.

[0104] In formula (A1), 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, 4, or 5. Considering the availability of raw materials, n5 of 0, 1, or 2 is preferred.

[0105] In equation (A1), R 3 The hydrocarbon group may contain a halogen atom, nitro group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. The hydrocarbon portion of the aforementioned hydrocarbon group, hydrocarbon oxy group, and hydrocarbon thio group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples can be listed in R. 1 The hydrocarbon groups represented are the same as those shown, but not limited to these. When n5 is 2, 3, 4 or 5, each R 3 They can be the same or different, 2 Rs 3 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0106] Specific examples of cations of sulfonium salt type monomers represented by formula (A) are shown below, but are not limited to these.

[0107] [Chemistry 10]

[0108]

[0109] [Chemistry 11]

[0110]

[0111] [Chemistry 12]

[0112]

[0113] [Chemistry 13]

[0114]

[0115] [Chemistry 14]

[0116]

[0117] [Chemistry 15]

[0118]

[0119] [Chemistry 16]

[0120]

[0121] [Chemistry 17]

[0122]

[0123] [Chemistry 18]

[0124]

[0125] [Chemistry 19]

[0126]

[0127] [Chemistry 20]

[0128]

[0129] [Chemistry 21]

[0130]

[0131] [Chemistry 22]

[0132]

[0133] [Chemistry 23]

[0134]

[0135] [Chemistry 24]

[0136]

[0137] [Chemistry 25]

[0138]

[0139] [Chemistry 26]

[0140]

[0141] [Chemistry 27]

[0142]

[0143] [Chemistry 28]

[0144]

[0145] [Chemistry 29]

[0146]

[0147] In formula (A), Z - It is a fluoroalkane sulfonic acid anion having an aromatic vinyl structure and an iodine atom. The aforementioned fluoroalkane sulfonic acid anion is preferably represented by the following formula (Z).

[0148] [Chemistry 30]

[0149]

[0150] In formula (Z), 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 of 0 is preferred. m2 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, m2 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better, and 0 or 1 being the most desirable. m3 is 0, 1, 2, or 3.

[0151] In formula (Z), m4 is 0 or 1. When m4 is 0, it is a benzene ring; when m4 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with m4 of 0 is preferred. m5 is 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 is 0, 1, 2, or 3.

[0152] In formula (Z), m7 is 0 or 1. When m7 is 0, it is a benzene ring; when m7 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with m7 of 0 is preferred. m8 is 1, 2, 3, or 4. Considering the availability of raw materials, m8 is preferably 1, 2, or 3, with 1 or 2 being even better. m9 is 0, 1, 2, or 3.

[0153] In formula (Z), m10 is 0, 1, 2, 3 or 4, with 0, 1, 2 or 3 being preferred, 1, 2 or 3 being even better, and 1 being the best. m11 is 0 or 1. m12 is 0 or 1.

[0154] When m1 is 0, then 0 ≤ m2 + m3 + m1² ≤ 4; when m1 is 1, then 0 ≤ m2 + m3 + m1² ≤ 6. Also, when m4 is 0, then 0 ≤ m5 + m6 ≤ 4; when m4 is 1, then 0 ≤ m5 + m6 ≤ 6. Also, when m7 is 0, then 0 ≤ m8 + m9 ≤ 5; when m7 is 1, then 0 ≤ m8 + m9 ≤ 7. Furthermore, regarding the number of iodine atoms in the anion, the more iodine atoms there are, the higher the absorption, especially for EUV, leading to reduced solvent solubility and a risk of precipitation in the resist composition. Therefore, 1 ≤ m2 + m5 + m8 ≤ 4 is preferable.

[0155] In equation (Z), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R A It is preferable to have a hydrogen atom or a methyl group, with a hydrogen atom being even better.

[0156] In equation (Z), R 11The halogen atom other than the iodine atom, nitro, cyano, hydroxyl, carboxyl, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxy group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms containing heteroatoms. The halogen atom other than the iodine atom is preferably a fluorine, chlorine, or bromine atom, with fluorine being more preferred. The hydrocarbon portion of the aforementioned hydrocarbon group, hydrocarbon oxy group, and hydrocarbon thio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, 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 these. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms. Similarly, a portion of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. This results in the possible inclusion of hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone, sulfonyl lactone, carboxylic anhydride (-C(=O)-OC(=O)-), and haloalkyl groups. When m3 is 2 or 3, each R... 11 They can be the same, or they can be different.

[0157] Furthermore, when m3 is 2 or 3, there are 2 R... 11 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Specific examples of the rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc. As a result, they can 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, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0158] In equation (Z), R 12The halogen atom other than the iodine atom, nitro, cyano, hydroxyl, carboxyl, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, a hydrocarbon oxygen group with 1 to 20 carbon atoms containing heteroatoms, a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms containing heteroatoms. Specific examples of the aforementioned halogen atoms other than the iodine atom include fluorine, chlorine, and bromine atoms. The hydrocarbon portion of the aforementioned hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon thio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include R... 11 The hydrocarbon groups represented are the same as those shown, but not limited to these. When m6 is 2 or 3, each R 12 They can be the same, or they can be different.

[0159] Also, when m6 is 2 or 3, there are 2 Rs. 12 They can also bond to each other and form rings together with the carbon atoms they are bonded to. The aforementioned rings are preferably 5- to 8-membered rings.

[0160] In equation (Z), R 13 The halogen atom other than the iodine atom, nitro, cyano, hydroxyl, carboxyl, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms, a hydrocarbon oxygen group with 1 to 20 carbon atoms containing heteroatoms, a hydrocarbon thio group with 1 to 20 carbon atoms containing heteroatoms, or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms containing heteroatoms. Specific examples of halogen atoms other than the iodine atom include fluorine, chlorine, and bromine atoms. The hydrocarbon portion of the aforementioned hydrocarbon group, hydrocarbon oxygen group, and hydrocarbon thio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include those related to R... 11 The hydrocarbon groups represented are the same as those shown, but not limited to these. When m9 is 2 or 3, each R 13 They can be the same, or they can be different.

[0161] Also, when m9 is 2 or 3, there are 2 Rs. 13 They can also bond to each other and form rings together with the carbon atoms they are bonded to. The aforementioned rings are preferably 5- to 8-membered rings.

[0162] In formula (Z), L A L B L C L D and L E Each bond can be independently a single bond, ether bond, ester bond, sulfonate bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. Among these, L... A Single bonds, ether bonds, ester bonds, or sulfonate bonds are preferred, with ether bonds, ester bonds, or sulfonate bonds being even more preferred. L B Single bonds, ether bonds, ester bonds, amide bonds, sulfonamide bonds, or sulfonate bonds are preferred, with ester bonds or sulfonate bonds being even more preferred. CSingle bonds, ether bonds, ester bonds, amide bonds, or sulfonate bonds are preferred, with single bonds, ether bonds, or ester bonds being even more preferred. D Single bonds, ether bonds, ester bonds, amide bonds, or sulfonate bonds are preferred, with single bonds, ether bonds, or ester bonds being even more preferred. E Single bonds, ether bonds, ester bonds, or sulfonate bonds are preferred, with single bonds, ether bonds, or ester bonds being even more preferred.

[0163] When m12 is 1, L A and L B It is preferable to bond to an adjacent carbon atom of the aromatic ring. In this case, substituents containing the aforementioned fluorosulfonic acid anion structure and substituents containing aromatic rings substituted with iodine atoms are expected to have higher sensitivity because they are located in closer spatial positions.

[0164] In formula (Z), X L1 and X L2 Each is an alkylene group consisting of 1 to 40 carbon atoms, which may be a single bond or may contain heteroatoms. These alkylene groups can be linear, branched, or cyclic; specific examples include alkane diols, cyclic saturated alkylene groups, and aryl groups. Specific examples of heteroatoms include oxygen atoms, nitrogen atoms, and sulfur atoms.

[0165] X L1 and X L2 Specific examples of hydrocarbon groups with 1 to 40 carbon atoms that may also contain heteroatoms are shown below, but are not limited to these. Furthermore, in the following formula, * denotes the groups that are related to L. A and L C 、 or L B and L D Atomic bonds.

[0166] [Chemistry 31]

[0167]

[0168] [Chemistry 32]

[0169]

[0170] [Chemistry 33]

[0171]

[0172] [Chemistry 34]

[0173]

[0174] Among these, X L -0~X L -22, X L -29~X L -34, and X L -47~XL -58 is better.

[0175] However, in equation (Z), m11 and m12 will not both be 0 at the same time, L A L B L C L D X L1 and X L2 It cannot be a single key at the same time.

[0176] In equation (Z), Q 1 and Q 2 Each group is independently composed of a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. The fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms is preferably trifluoromethyl.

[0177] In equation (Z), Q 3 and Q 4 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. The fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms is preferably trifluoromethyl. Q 3 and Q 4 It would be even better if it were a fluorine atom.

[0178] In equation (Z), -[C(Q) 1 (Q) 2 )] n6 -C(Q 3 (Q) 4 )-SO3 - Specific examples of the partial structure shown are preferably as follows, but are not limited to these. Furthermore, in the following formula, * indicates a relation to L. E Atomic bonds.

[0179] [Chemistry 35]

[0180]

[0181] Of these, Acid-1 to Acid-7 are better, and Acid-1 to Acid-3, Acid-6 and Acid-7 are even better.

[0182] Specific examples of the anions of sulfonium salt type monomers represented by formula (A) are shown below, but are not limited to these. Furthermore, in the following formula, R... A and Q 1 As mentioned above, Me is methyl. Furthermore, the bonding positions of the various substituents on the aromatic ring can be interchanged.

[0183] [Chemistry 36]

[0184]

[0185] [Chemistry 37]

[0186]

[0187] [Chemistry 38]

[0188]

[0189] [Chemistry 39]

[0190]

[0191] [Chemistry 40]

[0192]

[0193] [Chemistry 41]

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[0195] [Chemistry 42]

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[0197] [Chemistry 43]

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[0199] [Chemistry 44]

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[0204]

[0205] [Chemistry 47]

[0206]

[0207] [Chemistry 48]

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[0209] [Chemistry 49]

[0210]

[0211] [Transformation 50]

[0212]

[0213] [Chemistry 51]

[0214]

[0215] [Chemistry 52]

[0216]

[0217] [Chemistry 53]

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[0219] [Chemistry 54]

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[0223] [Chemistry 56]

[0224]

[0225] [Chemistry 57]

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[0228]

[0229] [Chemistry 59]

[0230]

[0231] [Transformation 60]

[0232]

[0233] [Chemistry 61]

[0234]

[0235] [Chemistry 62]

[0236]

[0237] [Chemistry 63]

[0238]

[0239] [Chemistry 64]

[0240]

[0241] [Chemistry 65]

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[0243] [Chemistry 66]

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[0245] [Chemistry 67]

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[0247] [Chemistry 68]

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[0249] [Chemistry 69]

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[0259] [Chemistry 74]

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[0273] [Chemistry 81]

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[0287] [Chemistry 88]

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[0289] [Chemistry 89]

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[0397] [Chemistry 143]

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[0399] [Chemistry 144]

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[0401] [Chemistry 145]

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[0407] [Chemistry 148]

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[0409] [Chemistry 149]

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[0413] [Chemistry 151]

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[0417] [Chemistry 153]

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[0421] [Chemistry 155]

[0422]

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[0425] [Chemistry 157]

[0426]

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[0433] [Chemistry 161]

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[0435] [Chemistry 162]

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[0437] [Chemistry 163]

[0438]

[0439] [Chemistry 164]

[0440]

[0441] [Chemistry 165]

[0442]

[0443] [Chemistry 166]

[0444]

[0445] The specific structure of the sulfonium salt type monomer of the present invention can be described by any combination of the aforementioned anions and cations.

[0446] The sulfonium salt type monomer of the present invention can be synthesized using known methods. For example, firstly, a sulfonium salt containing the aforementioned sulfonium cation can be synthesized using the synthesis method described in ARKIVOC (Gainesville, FL, United States) (2022), (7), 7-18. Then, the synthesized sulfonium salt can be converted into the target sulfonium salt by performing a salt exchange reaction with the corresponding anion. The salt exchange with the corresponding anion can be easily carried out using known methods, for example, Japanese Patent Application Publication No. 2007-145797.

[0447] Furthermore, the aforementioned manufacturing method is merely one example, and the manufacturing method of the matte salt of the present invention is not limited to this.

[0448] The structural features of the sulfonate monomer of the present invention include an aromatic vinyl structure as a polymerizable group, a fluorosulfonic acid anion structure with an iodine atom, and a cyano group bonded to the aromatic ring of the sulfonate cation. Regarding the iodine atom, especially in EUV lithography at a wavelength of 13.5 nm, due to the very high EUV absorption based on the iodine atom, secondary electrons are generated from the iodine atom during exposure. Because the anionic portion of the sulfonate monomer of the present invention has a polymerizable group, the polymer obtained using it becomes an anionic bonded acid generator with the anionic side bonded to the polymer backbone. That is, since acids bonded to the polymer backbone are generated, the diffusion of the generated acids can be suppressed. Furthermore, the polymerizable groups, especially those composed of styrene and vinylnaphthalene structures, are more rigid than polymerizable groups such as methacrylates, thus increasing the glass transition temperature (Tg) of the polymer. It is believed that the polymers, through the interaction of aromatic rings within or between polymers (π-π stacking effect), will align themselves regularly and correctly, exhibiting resistance to pattern collapse in the developer during micropattern formation. Furthermore, even in the etching step after micropattern formation, excellent etching resistance is observed due to the aromatic rings directly bonded to the main chain. On the other hand, the cyano groups substituted on the aromatic rings of the sulfonium cation are known to act as strong electron-attracting groups. It is believed that this lowers the LUMO energy level in the leading-edge orbital theory. Therefore, it becomes easier to accept secondary electrons generated by the iodine atom in the anion, promoting the decomposition of the cation and efficiently generating acid. Moreover, the nitrogen atom of the cyano group has a lone pair of electrons, and it is expected to interact with the protons of the generated acid, functioning as an acid diffusion-inhibiting group. Due to these additive effects, high sensitivity is achieved, preventing the decrease in resolution caused by acid diffusion blurring, and improving LWR and CDU. Therefore, the polymer of the present invention is particularly suitable as a material for chemically amplified positive resist compositions.

[0449] [polymer]

[0450] The polymer of the present invention contains repeating units (hereinafter also referred to as repeating unit A) derived from a sulfonium salt type monomer represented by formula (A).

[0451] The aforementioned polymer may also contain repeating units represented by formula (a1) (hereinafter also referred to as repeating unit a1.) or repeating units represented by formula (a2) (hereinafter also referred to as repeating unit a2.).

[0452] [Chemistry 167]

[0453]

[0454] In equations (a1) and (a2), R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0455] In equation (a1), X 1 It is a single bond, phenylene, naphthylene, or *-C(=O)-OX 11 - The phenylene or naphthylene group may also be substituted with a hydroxyl group, a nitro group, a cyano group, a saturated hydrocarbon group containing fluorine atoms with 1 to 10 carbon atoms, a saturated hydrocarbon oxygen group containing fluorine atoms with 1 to 10 carbon atoms, or a halogen atom. X 11 It is a saturated hydrocarbon group, phenylene group, or naphthylene group having 1 to 10 carbon atoms. The saturated hydrocarbon group may also contain hydroxyl groups, ether bonds, ester bonds, or lactone rings. * indicates an atomic bond with a carbon atom in the main chain.

[0456] In equation (a2), X 2 It represents a single bond or *-C(=O)-O-. * indicates an atomic bond with a carbon atom in the main chain. R 21 It can be a halogen atom, cyano group, hydroxyl group, nitro group, or a hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; a hydrocarbon oxygen group with 1 to 20 carbon atoms containing heteroatoms; a hydrocarbon carbonyl group with 2 to 20 carbon atoms containing heteroatoms; a hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms containing heteroatoms; or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms containing heteroatoms. a1 can be 0, 1, 2, 3, or 4, preferably 0 or 1. When a1 is 2, 3, or 4, each R... 21 They can be the same, or they can be different.

[0457] In equations (a1) and (a2), AL 1 and AL 2 Each of these groups is an acid-indestructible group. Specific examples of the aforementioned acid-indestructible groups can be found in, for example, those described in Japanese Patent Application Publication No. 2013-80033 and Japanese Patent Application Publication No. 2013-83821.

[0458] Typically, specific examples of the aforementioned unstable acid groups can be listed as those represented by formulas (AL-1) to (AL-3).

[0459] [Chemistry 168]

[0460]

[0461] In the formula, * represents an atomic bond.

[0462] In equations (AL-1) and (AL-2), R L1 and R L2 Each group consists of a hydrocarbon group with 1 to 40 carbon atoms, and may also contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. Preferably, the aforementioned hydrocarbon groups have 1 to 20 carbon atoms.

[0463] In formula (AL-1), a2 is an integer from 0 to 10, and it is better to be 1, 2, 3, 4 or 5.

[0464] In equation (AL-2), R L3 and R L4 Each group is independently composed of a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and may also contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. The aforementioned hydrocarbon groups are preferably those having 1 to 20 carbon atoms. Furthermore, R... L2 R L3 and R L4 Any two of them can also bond to each other and together with the carbon atoms they are bonded to, or carbon atoms and oxygen atoms, to form a ring with 3 to 20 carbon atoms. The aforementioned ring is preferably a ring with 4 to 16 carbon atoms, and more preferably an alicyclic ring.

[0465] In equation (AL-3), R L5 R L6 and R L7 Each group is an independent hydrocarbon group with 1 to 20 carbon atoms, and may also contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. The aforementioned hydrocarbon groups are preferably those with 1 to 20 carbon atoms. Also, R... L5 R L6 and R L7 Any two of them can also bond to each other and together with the carbon atoms they are bonded to form a ring with 3 to 20 carbon atoms. The aforementioned ring is preferably a ring with 4 to 16 carbon atoms, and more preferably an alicyclic ring.

[0466] Specific examples of repeating unit a1 can be listed below, but are not limited to these. Furthermore, in the following formula, R... A and AL 1 Same as above.

[0467] [Chemistry 169]

[0468]

[0469] [Chemistry 170]

[0470]

[0471] [Chemistry 171]

[0472]

[0473] [Chemistry 172]

[0474]

[0475] Specific examples of repeating unit a2 can be listed below, but are not limited to these. Furthermore, in the following formula, R... A and AL 2 Same as above.

[0476] [Chemistry 173]

[0477]

[0478] [Chemistry 174]

[0479]

[0480] [Chemistry 175]

[0481]

[0482] The aforementioned polymer may also contain repeating units represented by the following formula (a3) ​​(hereinafter also referred to as repeating unit a3).

[0483] [Chemistry 176]

[0484]

[0485] In formula (a3), b1 is 0 or 1. When b1 is 0, it is a benzene ring; when b1 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with b1 of 0 is preferred. b2 is 0, 1, 2, or 3 when b1 is 0, and 0, 1, 2, 3, 4, or 5 when b1 is 1. Considering the availability of raw materials, b2 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0486] In equation (a3), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Among these, hydrogen atoms and methyl groups are preferred, with hydrogen atoms being even more preferred.

[0487] In equation (a3), X 3 The bonds are single bonds, *-C(=O)-O-, or *-C(=O)-NH-. * 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 even better.

[0488] In equation (a3), X 4 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 availability of raw materials, a single bond, a carbonyl group, or a sulfonyl group is preferred; considering the polar group generated after the reaction, a single bond or a carbonyl group is even better.

[0489] In equation (a3), X 5 and X 6 Each can be independently an oxygen atom or a sulfur atom. However, X 4 and X 6 Bonded to adjacent carbon atoms in an aromatic ring. X 5 and X 6They can be the same or different; considering the perspective of reactivity, X 5 and X 6 Both are better if they contain oxygen atoms.

[0490] In equation (a3), R 22 and R 23 Each hydrocarbon group consists of 1 to 20 carbon atoms, which may be hydrogen atoms or may contain heteroatoms. The aforementioned hydrocarbon groups may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include alkyl groups with 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 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 these. 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 can 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.

[0491] Also, R 22 and R 23 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Specific examples of the rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc. As a result, they can 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, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0492] In equation (a3), R 24It may contain halogen atoms, hydroxyl groups, cyano groups, nitro groups, or hydrocarbon groups with 1 to 20 carbon atoms that may contain heteroatoms; hydrocarbon oxygen groups with 1 to 20 carbon atoms that may contain heteroatoms; hydrocarbon oxygen carbonyl groups with 2 to 20 carbon atoms that may contain heteroatoms; or hydrocarbon thio groups with 1 to 20 carbon atoms or -N(R) groups. 24A (R) 24B R 24A and R 24B Each 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 groups, as well as the hydrocarbon groups of the aforementioned hydrocarbon oxy, hydrocarbon oxycarbonyl, and hydrocarbon thio groups, can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed in relation to R. 22 and R 23 The same applies to the hydrocarbon groups exemplified above. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups can also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, these groups may also include hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonyl lactone ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. When b2 is 2 or more, each R... 24 They can be the same, or they can be different.

[0493] Furthermore, when b2 is 2 or more, multiple R 24 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. Specific examples of the rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. 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, halogen atoms, etc., and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc. As a result, they can 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, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0494] Specific examples of repeating unit a3 can be listed below, but are not limited to these. Furthermore, in the following formula, R... A As mentioned above, Me is methyl. Furthermore, the bonding positions of the various substituents on the aromatic ring can be interchanged.

[0495] [Chemistry 177]

[0496]

[0497] [Chemistry 178]

[0498]

[0499] [Chemistry 179]

[0500]

[0501] [Chemistry 180]

[0502]

[0503] [Chemistry 181]

[0504]

[0505] [Chemistry 182]

[0506]

[0507] [Chemistry 183]

[0508]

[0509] [Chemistry 184]

[0510]

[0511] [Chemistry 185]

[0512]

[0513] [Chemistry 186]

[0514]

[0515] [Chemistry 187]

[0516]

[0517] [Chemistry 188]

[0518]

[0519] [Chemistry 189]

[0520]

[0521] [Chemistry 190]

[0522]

[0523] [Chemistry 191]

[0524]

[0525] [Chemistry 192]

[0526]

[0527] [Chemistry 193]

[0528]

[0529] [Chemistry 194]

[0530]

[0531] [Chemistry 195]

[0532]

[0533] [Chemistry 196]

[0534]

[0535] [Chemistry 197]

[0536]

[0537] [Chemistry 198]

[0538]

[0539] [Chemistry 199]

[0540]

[0541] [Chem.200]

[0542]

[0543] [Chemical Engineering 201]

[0544]

[0545] [Chemical Engineering 202]

[0546]

[0547] [Chemical Engineering 203]

[0548]

[0549] [Chemical 204]

[0550]

[0551] [Chemical Engineering 205]

[0552]

[0553] [Chemical Engineering 206]

[0554]

[0555] [Chemical 207]

[0556]

[0557] [Chemical Engineering 208]

[0558]

[0559] [Chemical Engineering 209]

[0560]

[0561] [Chemical 210]

[0562]

[0563] [Chemistry 211]

[0564]

[0565] [Chemistry 212]

[0566]

[0567] [Chemistry 213]

[0568]

[0569] [Chemistry 214]

[0570]

[0571] [Chemical 215]

[0572]

[0573] [Chemistry 216]

[0574]

[0575] [Chemistry 217]

[0576]

[0577] [Chemistry 218]

[0578]

[0579] [Chemistry 219]

[0580]

[0581] [Chem.220]

[0582]

[0583] [Chemistry 221]

[0584]

[0585] [Chemistry 222]

[0586]

[0587] [Chemistry 223]

[0588]

[0589] [Chemistry 224]

[0590]

[0591] [Chemistry 225]

[0592]

[0593] [Chemistry 226]

[0594]

[0595] The aforementioned base polymer may also contain repeating units represented by formula (b1) (hereinafter also referred to as repeating unit b1.) or repeating units represented by formula (b2) (hereinafter also referred to as repeating unit b2.).

[0596] [Chemistry 227]

[0597]

[0598] In equations (b1) and (b2), R A Each can be independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. 1 It represents a single bond or *-C(=O)-O-. * indicates an atomic bond with a carbon atom in the main chain. R 31 It is a hydrogen atom, or a group containing at least one of the following structures with 1 to 20 carbon atoms: hydroxyl group (other than phenolic hydroxyl group), cyano group, carbonyl group, carboxyl group, ether bond, ester bond, sulfonate bond, carbonate bond, lactone ring, sulcinolone ring, and carboxylic anhydride (-C(=O)-OC(=O)-). R 32It can be a halogen atom, carboxyl group, nitro group, cyano group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxygen group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When c2 is 2, 3, or 4, each R 32 They can be the same or different. c1 can be 1, 2, 3 or 4. c2 can be 0, 1, 2, 3 or 4. However, 1 ≤ c1 + c2 ≤ 5.

[0599] Specific examples of repeating unit b1 may be listed below, but are not limited to these. Furthermore, in the following formula, R... A Same as above.

[0600] [Chemistry 228]

[0601]

[0602] [Chemistry 229]

[0603]

[0604] [Chemistry 230]

[0605]

[0606] [Chemistry 231]

[0607]

[0608] [Chemistry 232]

[0609]

[0610] [Chemistry 233]

[0611]

[0612] [Chemistry 234]

[0613]

[0614] [Chemistry 235]

[0615]

[0616] [Chemistry 236]

[0617]

[0618] [Chemistry 237]

[0619]

[0620] [Chemistry 238]

[0621]

[0622] [Chemistry 239]

[0623]

[0624] [Chemistry 240]

[0625]

[0626] [Chemistry 241]

[0627]

[0628] [Chemistry 242]

[0629]

[0630] [Chemistry 243]

[0631]

[0632] Specific examples of repeating unit b2 may be listed below, but are not limited to these. Furthermore, in the following formula, R... A Same as above.

[0633] [Chemistry 244]

[0634]

[0635] [Chemistry 245]

[0636]

[0637] [Chemistry 246]

[0638]

[0639] [Chemistry 247]

[0640]

[0641] [Chemistry 248]

[0642]

[0643] For repeating units b1 or b2, those with an lactone ring as a polar group are preferred for ArF lithography, while those with a phenol site are preferred for KrF lithography, EB lithography, and EUV lithography.

[0644] The aforementioned base polymer may also contain repeating units (hereinafter also referred to as repeating unit c) having a structure in which hydroxyl groups are protected by acid-indestructible groups. Repeating unit c has a structure in which one or more hydroxyl groups are protected, and there are no particular restrictions as long as the protecting groups decompose and generate hydroxyl groups due to the action of acid, and it is preferably represented by the following formula (c1).

[0645] [Chemistry 249]

[0646]

[0647] In equation (c1), R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 41 It can also contain heteroatoms and is a (d+1) valence hydrocarbon group with 1 to 30 carbon atoms. R 42 It is an acid-labile group. d can be 1, 2, 3, or 4.

[0648] In equation (c1), R 42 The acid-indestructible group can be any group that is protected by the acid and forms a hydroxyl group. R 42 The structure is not particularly limited, but it is preferable to have an acetal structure, a ketal structure, an alkoxy carbonyl group, or an alkoxy methyl group represented by the following formula (c2), especially an alkoxy methyl group represented by the following formula (c2).

[0649] [Chemistry 250]

[0650]

[0651] In the formula, * represents an atomic bond. R 43 It consists of hydrocarbon groups with 1 to 15 carbon atoms.

[0652] R 42 Specific examples of the acid-unstable group represented by formula (c2), the alkoxymethyl group represented by formula (c2), and the repeating unit c can be cited as those illustrated in the description of the repeating unit c described in Japanese Patent Application Publication No. 2020-111564.

[0653] The aforementioned base polymer may also contain repeating units d derived from indene, benzofuran, benzothiophene, acenaphthene, chromone, coumarin, norcamphediene, or derivatives thereof. Specific examples of monomers providing repeating units d may be listed below, but are not limited to these.

[0654] [Chemistry 251]

[0655]

[0656] The aforementioned base polymer may also contain repeating units e derived from dihydroindene, vinylpyridine, or vinylcarbazole.

[0657] In the polymer of the present invention, the content ratios of the repeating units A, a1, a2, a3, b1, b2, c, d, and e are preferably 0 < A ≤ 0.4, 0 ≤ a1 ≤ 0.8, 0 ≤ a2 ≤ 0.8, 0 ≤ a3 ≤ 0.6, 0 < a1 + a2 + a3 ≤ 0.8, 0 ≤ b1 ≤ 0.6, 0 ≤ b2 ≤ 0.6, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.3, and 0 ≤ e ≤ 0.3, more preferably 0 < A ≤ 0.3, 0 ≤ a1 ≤ 0.7, 0 ≤ a2 ≤ 0.7, 0 ≤ a3 ≤ 0.5, 0 < a1 + a2 + a3 ≤ 0.7, 0 ≤ b1 ≤ 0.5, 0 ≤ b2 ≤ 0.5, 0 ≤ c ≤ 0.3, 0 ≤ d ≤ 0.3, and 0 ≤ e ≤ 0.3. However, A + a1 + a2 + a3 + b1 + b2 + c + d + e ≤ 1.0.

[0658] The weight-average molecular weight (Mw) of the aforementioned polymer is preferably 1,000 to 500,000, more preferably 3,000 to 100,000. If Mw is within this range, sufficient etching resistance can be obtained without fear of a decrease in resolution due to the inability to ensure the difference in dissolution rates before and after exposure. Moreover, in the present invention, Mw is a polystyrene conversion measurement value obtained by gel permeation chromatography (GPC) using THF or N,N-dimethylformamide (DMF) as a solvent.

[0659] Furthermore, as the pattern rule is miniaturized, the influence of the molecular weight distribution (Mw / Mn) of the aforementioned polymer tends to become larger. Therefore, in order to obtain a resist composition suitable for a fine pattern size, a narrow dispersion with Mw / Mn of 1.0 to 2.0 is preferred. If it is within the above range, there are few low-molecular-weight and high-molecular-weight polymers, and after exposure, there is no fear of observing foreign substances on the pattern or deterioration of the pattern shape.

[0660] To synthesize the aforementioned polymer, for example, monomers providing the aforementioned repeating units can be added with a radical polymerization initiator and heated in an organic solvent to carry out polymerization.

[0661] Specific examples of organic solvents used in polymerization include toluene, benzene, THF, diethyl ether, dioxane, cyclohexane, cyclopentane, methyl ethyl ketone (MEK), propylene glycol monomethyl ether acetate (PGMEA), and γ-butyrolactone (GBL). Specific examples of polymerization initiators include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylpentanonitrile), 2,2-azobis(methyl 2-methylpropionate), 1,1'-azobis(1-acetoxy-1-phenylethane), benzoyl peroxide, and lauroyl peroxide. The amount of these initiators added relative to the total monomers to be polymerized should preferably be 0.01–25 mol%. The reaction temperature should preferably be 50–150°C, and more preferably 60–100°C. The reaction time should preferably be 2–24 hours, and from a production efficiency perspective, 2–12 hours is more preferred.

[0662] The aforementioned polymerization initiator can be added to the monomer solution and supplied to the reactor, or the monomer solution and initiator solution can be prepared separately and supplied to the reactor independently. During the standby time, there is a possibility that polymerization will occur due to free radicals generated by the initiator, resulting in ultra-high molecular weight polymers. Therefore, from a quality management perspective, it is preferable that the monomer solution and initiator solution be prepared independently and added dropwise. Acid-unstable groups can be used directly introduced into the monomer, or they can be protected or partially protected after polymerization. Furthermore, to adjust the molecular weight, known chain transfer agents such as dodecyl mercaptan and 2-mercaptoethanol can be used concurrently. In this case, the amount of these chain transfer agents added relative to the total amount of monomers to be polymerized should preferably be 0.01–20 mol%.

[0663] When monomers contain hydroxyl groups, the hydroxyl groups can be replaced with acetal groups such as ethoxy-ethoxy, which are easily deprotected by acids, during polymerization. After polymerization, the hydroxyl groups can be deprotected by weak acids and water. Alternatively, they can be replaced with acetyl, formyl, neopentyl, etc., before polymerization and then subjected to alkaline hydrolysis.

[0664] When copolymerizing hydroxystyrene or hydroxyvinylnaphthalene, hydroxystyrene or hydroxyvinylnaphthalene can be copolymerized with other monomers in an organic solvent, with the addition of a free radical polymerization initiator and heating. Alternatively, acetoxystyrene or acetoxyvinylnaphthalene can be used, and after polymerization, the acetoxy groups can be deprotected by alkaline hydrolysis to become polyhydroxystyrene or hydroxyvinylnaphthalene.

[0665] The alkali used in alkaline hydrolysis can be ammonia, triethylamine, etc. Furthermore, the reaction temperature should preferably be -20 to 100°C, more preferably 0 to 60°C. The reaction time should preferably be 0.2 to 100 hours, more preferably 0.5 to 20 hours.

[0666] Furthermore, the amount of each monomer in the aforementioned monomer solution can be appropriately set, for example, in a manner that results in a preferred content ratio for the aforementioned repeating unit.

[0667] The polymer obtained by the aforementioned manufacturing method can be used as the final product by using the reaction solution obtained by the polymerization reaction, or it can be used as the final product by using the purification steps such as adding the polymer liquid to a poor solvent to obtain the powder and then reprecipitating it. Considering the viewpoints of work efficiency and quality stabilization, it is better to use the polymer solution in which the powder obtained by the purification step is dissolved in the solvent as the final product.

[0668] Specific examples of solvents used at this time can be cited from paragraphs

[0144] to

[0145] of Japanese Patent Application Publication No. 2008-111103, including ketones such as cyclohexanone and methyl-2-n-pentanone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; and propylene glycol monomethyl ether (PGME), ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, and propylene glycol dimethyl ether. Ethers such as diethylene glycol dimethyl ether; esters such as PGMEA, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as GBL; alcohols such as diacetone alcohol (DAA); high-boiling-point alcohol solvents such as diethylene glycol, propylene glycol, glycerol, 1,4-butanediol, and 1,3-butanediol; and mixed solvents of these.

[0669] In the aforementioned polymer solution, the polymer concentration is preferably 0.01–30% by mass, and more preferably 0.1–20% by mass.

[0670] The aforementioned reaction solutions and polymer solutions are preferably filtered. Filtering removes foreign matter and colloids that could cause defects, thus effectively stabilizing the quality.

[0671] The materials used in the aforementioned filters include fluorocarbon-based, cellulose-based, nylon-based, polyester-based, and hydrocarbon-based materials. For filtration steps involving corrosion inhibitors, filters made of fluorocarbon-based materials such as Teflon (a registered trademark), polyethylene, polypropylene, or nylon are preferred. The pore size of the filter can be appropriately selected according to the target cleanliness level, preferably below 100 nm, and more preferably below 20 nm. Furthermore, these filters can be used individually or in combination. The filtration method can preferably involve passing the solution through only once, or circulating the solution for multiple filtrations. The filtration steps can be performed in any order and number of times during the polymer manufacturing process, preferably filtering the reaction solution, polymer solution, or both after the polymerization reaction.

[0672] [Chemical amplification resist composition]

[0673] [(A) Basic Polymer]

[0674] The chemically amplified resist composition of the present invention comprises a base polymer containing the aforementioned polymer as component (A).

[0675] The aforementioned polymers may be used alone or in combination with two or more polymers having different composition ratios, Mw and / or Mw / Mn. Furthermore, (A) the base polymer may include, in addition to the aforementioned polymers, hydrides of ring-opening shift polymers; in this case, those described in Japanese Patent Application Publication No. 2003-66612 may be used.

[0676] [(B) Organic solvents]

[0677] The chemically amplified resist composition of the present invention may also include an organic solvent as component (B). Regarding the organic solvent (B), it is not particularly limited as long as it can dissolve the aforementioned components and the components described below. Specific examples of such organic solvents include ketones such as cyclopentanone, cyclohexanone, and methyl-2-n-pentanone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ketols such as DAA; ethers such as PGME, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as PGMEA, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as GBL; and mixed solvents of these.

[0678] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, cyclohexanone, GBL, ethyl lactate, DAA, and mixed solvents thereof are preferred as they have particularly good solubility for component (A), i.e., the base polymer.

[0679] In the chemically amplified resist composition of the present invention, the content of (B) organic solvent relative to 80 parts by mass of (A) base polymer is preferably 200 to 7000 parts by mass, and more preferably 400 to 5000 parts by mass. (B) organic solvent may be used alone or in combination with two or more other types.

[0680] [(C) Quenching agent]

[0681] The chemically amplified resist composition of the present invention may also include a quencher as component (C). Furthermore, the quencher in the present invention is a material used to prevent diffusion toward the unexposed area by capturing the acid generated by the photoacid generator in the chemically amplified resist composition, thereby forming the desired pattern.

[0682] (C) Specific examples of quenching agents can be listed as onion salts represented by formula (1) or (2).

[0683] [Chemistry 252]

[0684]

[0685] In equation (1), R q1 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain hydrogen atoms or heteroatoms, but excludes those in which the hydrogen atom at the α-position of the sulfonic acid group is replaced by a fluorine atom or a fluoroalkyl group. In formula (2), R q2 Hydrocarbon groups consisting of 1 to 40 carbon atoms, which may also contain heteroatoms.

[0686] R q1 Specifically, the hydrocarbon groups representing 1 to 40 carbon atoms can include alkyl groups with 1 to 40 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, and tricyclic [5.2.1.0]. 2,6 Decyl, adamantyl, and other cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms; phenyl, naphthyl, anthracene, and other aryl groups with 6 to 40 carbon atoms. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups may 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 groups may be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, these groups may also contain hydroxyl, fluorine, chlorine, bromine, iodine, cyano, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonyl lactone ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc.

[0687] R q2 Specifically, the hydrocarbon group represented, except for R q1 The specific examples of substituents shown may also include fluorinated saturated hydrocarbon groups such as trifluoromethyl and trifluoroethyl, fluorinated aryl groups such as pentafluorophenyl and 4-trifluoromethylphenyl. Specific examples of the anions of onium salts represented by formula (1) may be shown below, but are not limited to these.

[0688] [Chemistry 253]

[0689]

[0690] [Chemistry 254]

[0691]

[0692] [Chemistry 255]

[0693]

[0694] [Chemistry 256]

[0695]

[0696] [Chemistry 257]

[0697]

[0698] Specific examples of onium salt anions represented by equation (2) are shown below, but are not limited to these.

[0699] [Chemistry 258]

[0700]

[0701] [Chemistry 259]

[0702]

[0703] [Chemistry 260]

[0704]

[0705] [Chemistry 261]

[0706]

[0707] [Chemistry 262]

[0708]

[0709] In equations (1) and (2), Mq + The aforementioned onium cation may include sulfonium cation, monium cation, ammonium cation, etc. Specific examples of the aforementioned sulfonium cation may include those exemplified in Formula (A), those described in paragraphs

[0102] to

[0125] of Japanese Patent Application Publication No. 2024-3744, those described in paragraphs

[0044] to

[0049] of International Publication No. 2024 / 128017, and those described in paragraphs

[0035] to

[0046] of Japanese Patent Application Publication No. 7491173, but are not limited to these.

[0710] Furthermore, among the aforementioned sulfonium cations, the sulfonium cation represented by the formula (sulfo-1) is also preferred.

[0711] [Chemistry 263]

[0712]

[0713] In formula (sulfo-1), e1 is 0 or 1. When e1 is 0, it is a benzene ring; when e1 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with e1 of 0 is preferred. e2 is 0 or 1. When e2 is 0, it is a benzene ring; when e2 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with e2 of 0 is preferred. e3 is 0 or 1. When e3 is 0, it is a benzene ring; when e3 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with e3 of 0 is preferred.

[0714] In formula (sulfo-1), e4 is 0, 1, 2, 3, or 4. The more iodine atoms in the cationic structure, the higher the absorption of EUV, which may lead to poor solvent solubility and precipitation in the resist composition. Therefore, e4 is preferred to be 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0715] In formula (sulfo-1), e5 is 0, 1, 2, 3, or 4. Considering the availability of raw materials, e5 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better. e6 is 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, e6 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better. e7 is 0, 1, 2, 3, 4, 5, or 6. Considering the availability of raw materials, e7 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0716] In formula (sulfo-1), e8 is 0, 1, or 2. Considering the availability of raw materials, e8 is preferably 0 or 1. e9 is 0, 1, or 2. Considering the availability of raw materials, e9 is preferably 0 or 1. e10 is 0, 1, or 2. Considering the availability of raw materials, e10 is preferably 0 or 1.

[0717] In formula (sulfo-1), e11 is 0 or 1. When e11 is 0, it is a benzene ring; when e11 is 1, it is a naphthalene ring. Considering solvent solubility, a benzene ring with e11 of 0 is preferred.

[0718] In formula (sulfo-1), e12 is 0, 1, 2, 3, or 4. The more iodine atoms in the cationic structure, the higher the absorption of EUV, which can lead to poor solvent solubility and precipitation in the resist composition. Therefore, e12 is preferably 0, 1, 2, or 3, with 0, 1, or 2 being even better.

[0719] In formula (sulfo-1), e13 is 0, 1, or 2. From the perspective of raw material availability, e13 is preferably 0 or 1. e14 is 0, 1, or 2. From a synthetic perspective, e14 is preferably 0 or 1.

[0720] However, when e1 is 0, then 0 ≤ e6 + e9 ≤ 4; when e1 is 1, then 0 ≤ e6 + e9 ≤ 6. When e2 is 0, then 0 ≤ e7 + e10 ≤ 4; when e2 is 1, then 0 ≤ e7 + e10 ≤ 6. When e3 is 0, then 1 ≤ e4 + e5 + e8 + e14 ≤ 4; when e3 is 1, then 1 ≤ e4 + e5 + e8 + e14 ≤ 6. When e11 is 0, then 0 ≤ e12 + e13 ≤ 4; when e11 is 1, then 0 ≤ e12 + e13 ≤ 6. Also, e4 + e12 ≥ 1.

[0721] In formula (sulfo-1), R F1 ~R F3 Each of these groups 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 e5 is 2, 3, or 4, each R... F1 They can be the same or different. When e6 is 2, 3, 4, 5 or 6, each R F2 They can be the same or different. When e7 is 2, 3, 4, 5 or 6, each R F3 They can be the same or different.

[0722] In formula (sulfo-1), R q11 ~R q14 The hydrocarbon group can be a halogen atom other than iodine and fluorine atoms, a nitro group, a cyano group, a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms, an alkyl group with 1 to 20 carbon atoms that may contain heteroatoms, or an alkylthio group with 1 to 20 carbon atoms that may contain heteroatoms. The hydrocarbon portion of the aforementioned hydrocarbon group, alkyl group, and alkylthio group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be found in the description of formula (A) under R. 1 The same applies to the hydrocarbon groups exemplified above. Furthermore, some or all of the hydrogen atoms in the hydrocarbon portions of the aforementioned hydrocarbon groups, hydroxyl groups, and thiol groups may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. Similarly, a portion of the -CH2- group in the aforementioned hydrocarbon groups may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, the hydrocarbon groups may also include 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.

[0723] Also, when e8 is 2, there are 2 Rs. q11 They can be the same or different, 2 Rs q11 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When e9 is 2, there are 2 R atoms. q12 They can be the same or different, 2 Rs q12They can also bond to each other and form rings together with the carbon atoms they are bonded to. When e10 is 2, there are 2 R atoms. q13 They can be the same or different, 2 Rs q13 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When e13 is 2, there are 2 R atoms. q14 They can be the same or different, 2 Rs q14 They can also bond to each other and form rings together with the carbon atoms they are bonded to. Specific examples of the rings formed in this case include cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, norbornene rings, adamantane rings, etc. Furthermore, some or all of the hydrogen atoms in the aforementioned rings can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and part of the -CH2- in the aforementioned rings can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc. As a result, they can 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, sulopentalide rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0724] Furthermore, the direct bond in the sulfonium cation represented by formula (sulfo-1) to S + The aromatic rings can also bond with each other and with S + Together they form a ring. Specific examples of the aforementioned ring structure can be exemplified by the following formulas, etc.

[0725] [Chemistry 264]

[0726]

[0727] In the formula, the dashed lines represent atomic bonds.

[0728] In formula (sulfo-1), L F and L G 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... F Single bonds, ether bonds, ester bonds, or sulfonate bonds are preferred, with ester bonds or sulfonate bonds being even more preferred. L G Single bonds, ether bonds, or ester bonds are preferred, with single bonds being even better.

[0729] In formula (sulfo-1), X L3 A single-bonded or heteroatom-containing hydrocarbon group with 1 to 40 carbon atoms. The aforementioned hydrocarbon group can be linear, branched, or cyclic; specific examples include alkane dimethyl groups, cyclic saturated hydrocarbon groups, and aryl groups. Specific examples of the aforementioned heteroatom include oxygen atoms, nitrogen atoms, and sulfur atoms. X L3Specific examples of hydrocarbon groups with 1 to 40 carbon atoms that may also contain heteroatoms can be exemplified in the description of formula (Z) in the X section. L1 and X L2 The example X, which may also contain a heteroatom of a hydrocarbon group having 1 to 40 carbon atoms, is illustrated in the following examples. L -0~X L -58. Among these, X L3 It is advisable to be X L -0~X L -22, X L -29~X L -34 and X L -47~X L -58.

[0730] The sulfonium cation represented by formula (sulfo-1) should preferably be represented by the following formula (sulfo-1-1).

[0731] [Chemistry 265]

[0732]

[0733] In the formula, e4~e10, e12~e14, R F1 ~R F3 R q11 ~R q14 L F L G and X L3 Same as above.

[0734] The sulfonium cation represented by formula (sulfo-1-1) is preferably represented by formula (sulfo-1-2).

[0735] [Chemistry 266]

[0736]

[0737] In the formula, e4~e10, R F1 ~R F3 and R q11 ~R q13 Same as above.

[0738] Specific examples of sulfonium cations represented by formula (sulfo-1) are shown below, but are not limited to these. Furthermore, in the following formula, Me is a methyl group.

[0739] [Chemistry 267]

[0740]

[0741] [Chemistry 268]

[0742]

[0743] [Chemistry 269]

[0744]

[0745] [Chemistry 270]

[0746]

[0747] [Chemistry 271]

[0748]

[0749] [Chemistry 272]

[0750]

[0751] [Chemistry 273]

[0752]

[0753] [Chemistry 274]

[0754]

[0755] [Chemistry 275]

[0756]

[0757] [Chemistry 276]

[0758]

[0759] [Chemistry 277]

[0760]

[0761] [Chemistry 278]

[0762]

[0763] [Chemistry 279]

[0764]

[0765] [Chemistry 280]

[0766]

[0767] [Chemistry 281]

[0768]

[0769] [Chemistry 282]

[0770]

[0771] [Chemistry 283]

[0772]

[0773] [Chemistry 284]

[0774]

[0775] [Chemistry 285]

[0776]

[0777] [Chemistry 286]

[0778]

[0779] [Chemistry 287]

[0780]

[0781] [Chemistry 288]

[0782]

[0783] [Chemistry 289]

[0784]

[0785] [Chemistry 290]

[0786]

[0787] [Chemistry 291]

[0788]

[0789] [Chemistry 292]

[0790]

[0791] [Chemistry 293]

[0792]

[0793] [Chemistry 294]

[0794]

[0795] Specific examples of the aforementioned citric acid can be cited from paragraph

[0181] of Japanese Patent Application Publication No. 2024-259, but are not limited to these.

[0796] Specific examples of the aforementioned ammonium cations can be represented by the following formula (am-1).

[0797] [Chemistry 295]

[0798]

[0799] In equation (am-1), R q21 ~R q24 Each can be an independent hydrocarbon group with 1 to 40 carbon atoms, and may also contain heteroatoms. Also, R q21 and R q22 They can also bond to each other and form rings together with the nitrogen atoms to which they are bonded. Specific examples of the aforementioned hydrocarbon groups can be found in the description of R in formula (A). 1 The hydrocarbon group represented is the same as that shown.

[0800] Specific examples of ammonium cations represented by formula (am-1) are shown below, but are not limited to these.

[0801] [Chemistry 296]

[0802]

[0803] Specific examples of onium salts represented by formula (1) or (2) can be listed as any combination of the aforementioned anions and cations. Furthermore, these onium salts can be easily prepared by ion exchange reactions using known organic chemical methods. For example, Japanese Patent Application Publication No. 2007-145797 can be consulted regarding ion exchange reactions.

[0804] The onium salts represented by formula (1) or (2) function as quenchers in the chemically amplified resist composition of the present invention. This is because the relative anions of the aforementioned onium salts are conjugate bases of weak acids. Here, "weak acid" means an acidity that cannot be protected by the acid-instable groups of the units containing acid-instable groups used in the base polymer. The onium salts represented by formula (1) or (2) function as quenchers when used in combination with onium salt-type photoacid generators that have a conjugate base of a strong acid such as sulfonic acid with fluorinated α-position as a relative anion. That is, when an onium salt that produces a strong acid such as sulfonic acid with fluorinated α-position is mixed with an onium salt that produces a weak acid such as unfluorinated sulfonic acid or carboxylic acid, the strong acid generated by the photoacid generator is irradiated by high-energy rays and collides with the onium salt having unreacted weak acid anions, resulting in the release of weak acid due to salt exchange and the generation of an onium salt with strong acid anions. During this process, the strong acid will exchange with the weak acid with lower catalytic energy, so the acid will obviously lose its activity and thus the diffusion of acid can be controlled.

[0805] Furthermore, (C) the quenching agent may also be an onium salt having a sulfonium cation and a benzene oxide anion site in the same molecule as described in Japanese Patent No. 6848776, as well as an onium salt having a sulfonium cation and a carboxylate anion site in the same molecule as described in Japanese Patent No. 6583136, Japanese Patent Application Publication No. 2020-200311, and an onium salt having a monazine cation and a carboxylate anion site in the same molecule as described in Japanese Patent No. 6274755.

[0806] Therefore, it is believed that when the photoacid generator producing strong acids is an onium salt, as mentioned above, the strong acid generated by high-energy ray irradiation can exchange with a weak acid. On the other hand, the weak acid generated by high-energy ray irradiation is difficult to collide with the onium salt that produces unreacted strong acid to undergo salt exchange. This is because onium cations readily form ion pairs with the anions of stronger acids.

[0807] When the chemically amplified resist composition of the present invention contains an onium salt represented by formula (1) or (2) as a quencher (C), its content is preferably 0.1 to 20 parts by mass relative to 80 parts by mass of the base polymer (A), and more preferably 0.1 to 10 parts by mass. If the content of the onium salt-type quencher in component (C) is within the aforementioned range, the resolution is good and the sensitivity does not decrease significantly, which is ideal. The onium salt represented by formula (1) or (2) can be used alone or in combination of two or more.

[0808] The chemically amplified resist composition of the present invention may also include a nitrogen-containing compound as a quencher (C). Specific examples of nitrogen-containing compounds as component (C) include the first-, second-, or third-order amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Application Publication No. 2008-111103, particularly amine compounds having hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, or sulfonate bonds. Furthermore, compounds in which a first- or second-order amine is protected with a carbamate group, as described in Japanese Patent Publication No. 3790649, may also be cited.

[0809] Alternatively, sulfonate sulfonates with nitrogen-containing substituents can be used as nitrogen-containing compounds. Such compounds function as quenchers in the unexposed areas, while the exposed areas lose their quenching ability due to neutralization with the acid they generate, and instead function as so-called photodegrading bases. By using photodegrading bases, the contrast between the exposed and unexposed areas can be further enhanced. For example, Japanese Patent Application Publication Nos. 2009-109595 and 2012-46501 can be found regarding photodegrading bases.

[0810] When the chemically amplified resist composition of the present invention includes a nitrogen-containing compound as a quencher (C), its content relative to 80 parts by mass of the base polymer (A) is preferably 0.001 to 12 parts by mass, and more preferably 0.01 to 8 parts by mass. The aforementioned nitrogen-containing compound may be used alone or in combination of two or more.

[0811] [(D) Photoacid generator]

[0812] The chemically amplified resist composition of the present invention may also include a photoacid generator as component (D). The aforementioned photoacid generator is not particularly limited to any compound that produces acid upon irradiation by high-energy rays. Preferred photoacid generators may be represented by formulas (3) or (4).

[0813] [Chemistry 297]

[0814]

[0815] In equation (3), R 101 ~R 105 Each group consists of a halogen atom or may contain heteroatoms and is a hydrocarbon group with 1 to 20 carbon atoms. Also, R 101 R 102 and R 103 Any two of them can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

[0816] Specific examples of sulfonium salt cations represented by formula (3) may include those exemplified by specific examples of sulfonium cations in formula (A), those described in paragraphs

[0102] to

[0125] of Japanese Patent Application Publication No. 2024-3744, those described in paragraphs

[0044] to

[0049] of International Publication No. 2024 / 128017, those described in paragraphs

[0035] to

[0046] of Japanese Patent Application Publication No. 7491173, and those exemplified by specific examples of sulfonium cations represented by formula (sulfo-1), but are not limited to these. Specific examples of ferrous salt cations represented by formula (4) may include those described in paragraph

[0181] of Japanese Patent Application Publication No. 2024-259, but are not limited to these.

[0817] In equations (3) and (4), Xa - It is the anion of a strong acid. The anions of the aforementioned strong acids can be represented by any of the formulas (Xa-1) to (Xa-4).

[0818] [Chemistry 298]

[0819]

[0820] In formula (Xa-1), R faIt 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 found with R in the formula (Xa-1-1) described later. fa1 The hydrocarbon group represented is the same as that shown.

[0821] The anion represented by formula (Xa-1) should preferably be represented by the following formula (Xa-1-1).

[0822] [Chemistry 299]

[0823]

[0824] In equation (Xa-1-1), Q 1 and Q 2 Each component is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms; for improved solvent solubility, at least one of these components is preferably trifluoromethyl. m can be 0, 1, 2, 3, or 4, with 1 being particularly preferred. R fa1 The hydrocarbon group may contain heteroatoms and has 1 to 35 carbon atoms. The aforementioned heteroatoms are preferably oxygen, nitrogen, sulfur, or halogen atoms, with oxygen atoms being more preferred. Considering the need for high resolution during the formation of fine patterns, the aforementioned hydrocarbon group has 6 to 30 carbon atoms.

[0825] In formula (Xa-1-1), R fa1 The hydrocarbon group represented has 1 to 35 carbon atoms and can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. Specific examples include alkyl groups with 1 to 35 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecanyl, and icosyl; cyclic saturated hydrocarbon groups with 3 to 35 carbon atoms, such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norcamphenyl, norcamphenylmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl; unsaturated aliphatic hydrocarbon groups with 2 to 35 carbon atoms, such as 2-propenyl and 3-cyclohexenyl; aryl groups with 6 to 35 carbon atoms, such as phenyl, 1-naphthyl, 2-naphthyl, and 9-fluorenyl; aralkyl groups with 7 to 35 carbon atoms, such as benzyl and diphenylmethyl; and groups obtained by combining these.

[0826] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms. Similarly, a portion of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. This results in the possible inclusion of hydroxyl, fluorine, chlorine, bromine, iodine, cyano, nitro, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. Specific examples of hydrocarbon groups containing heteroatoms include tetrahydrofuranyl, methoxymethyl, ethoxymethyl, methylthiomethyl, acetaminomethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetoxymethyl, 2-carboxy-1-cyclohexyl, 2-oxopropyl, 4-oxo-1-adamantyl, 3-oxocyclohexyl, etc.

[0827] In equation (Xa-1-1), L a1 The bonds can be single bonds, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, or carbamate bonds. From a synthetic point of view, ether bonds or ester bonds are preferred, with ester bonds being even better.

[0828] Specific examples of anions represented by formula (Xa-1) are shown below, but are not limited to these. Furthermore, in the following formula, Q... 1 As mentioned above, Ac is an acetyl group.

[0829] [Chemical 300]

[0830]

[0831] [Chemical Engineering 301]

[0832]

[0833] [Chemical 302]

[0834]

[0835] [Chemical 303]

[0836]

[0837] [Chemical 304]

[0838]

[0839] [Chemical 305]

[0840]

[0841] [Chemical 306]

[0842]

[0843] [Chemical 307]

[0844]

[0845] [Chemical 308]

[0846]

[0847] [Chemical 309]

[0848]

[0849] In formula (Xa-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 alkyl groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be found in R in formula (Xa-1-1). fa1 The hydrocarbon group represented is the same as that shown. R fb1 and R fb2 It should preferably be a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fb1 and R fb2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-N). - -SO2-CF2-) together form a ring, at which point R fb1 and R fb2 The groups formed by mutual bonding should preferably be fluorinated ethylidene or fluorinated propylene.

[0850] In formula (Xa-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 alkyl groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be found in R in formula (Xa-1-1). fa1 The hydrocarbon group represented is the same as that shown. R fc1 R fc2 and R fc3 It should preferably be a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fc1 and R fc2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-C). - -SO2-CF2-) together form a ring, at which point R fc1 and R fc2 The groups formed by mutual bonding should preferably be fluorinated ethylidene or fluorinated propylene.

[0851] In formula (Xa-4), R fdIt can be a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed with R in formula (Xa-1-1). fa1 The hydrocarbon group represented is the same as that shown.

[0852] Specific examples of anions represented by formula (Xa-4) are shown below, but are not limited to these.

[0853] [Chemical 310]

[0854]

[0855] [Chemistry 311]

[0856]

[0857] The examples of the aforementioned 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 exemplified by those represented by the following formula (Xa-5).

[0858] [Chemistry 312]

[0859]

[0860] In equation (Xa-5), x is 1, 2, or 3. y is 1, 2, 3, 4, or 5.

[0861] z can be 0, 1, 2, or 3. However, 1 ≤ y + z ≤ 5. It is better for y to be 1, 2, or 3, with 2 or 3 being even better. z should ideally be 0, 1, or 2.

[0862] In equation (Xa-5), X BI When x and / or y are 2 or more, they can be the same or different from each other.

[0863] In equation (Xa-5), L 1 It is a saturated hydrocarbon group with 1 to 6 carbon atoms, consisting of a single bond, ether bond, or ester bond, or may also include an ether bond or ester bond. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic.

[0864] In equation (Xa-5), L 2 When x is 1, it is a single bond or a divalent linker with 1 to 20 carbon atoms; when x is 2 or 3, it is a (x+1) valent linker with 1 to 20 carbon atoms. The linker may also contain oxygen, sulfur or nitrogen atoms.

[0865] In formula (Xa-5), R feThe carbon group may be a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon oxygen group having 1 to 20 carbon atoms, a hydrocarbon carbonyl group having 2 to 20 carbon atoms, a hydrocarbon oxygen carbonyl group having 2 to 20 carbon atoms, a hydrocarbon carbonyl group having 2 to 20 carbon atoms, a hydrocarbon carbonyl oxygen group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyl oxygen group having 1 to 20 carbon atoms, or a -N(R) group, which may contain a hydroxyl, carboxyl, fluorine, chlorine, bromine, or amino group, or may also contain a fluorine, chlorine, bromine, hydroxyl, amino, or ether bond. feA (R) feB ), -N(R feC )-C(=O)-R feD or -N(R) feC )-C(=O)-OR feD R feA and R feB Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R feC It is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxygen group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl oxygen group having 2 to 6 carbon atoms. R feD It can be an aliphatic hydrocarbon group with 1 to 16 carbon atoms, an aryl group with 6 to 12 carbon atoms, or an aralkyl group with 7 to 15 carbon atoms. It may also contain halogen atoms, hydroxyl groups, saturated alkyloxy groups with 1 to 6 carbon atoms, saturated alkylcarbonyl groups with 2 to 6 carbon atoms, or saturated alkylcarbonyloxy groups with 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. The aforementioned hydrocarbon group, alkyloxy group, alkylcarbonyl group, alkyloxycarbonyl group, alkylcarbonyloxy group, and alkylsulfonyloxy group can be straight-chain, branched, or cyclic. When x and / or z are 2 or more, each R... fe They can be the same or different.

[0866] Among these, R fe It is advisable to use hydroxyl groups, -N(R) feC )-C(=O)-R feD -N(R) feC )-C(=O)-OR feD Fluorine atoms, chlorine atoms, bromine atoms, methyl groups, methoxy groups, etc.

[0867] In equation (Xa-5), Rf 11 ~Rf 14 Each is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, at least one of which is a fluorine atom or a trifluoromethyl group. Also, Rf 11 With Rf 12 They can also form carbonyl groups together. In particular, Rf 13 and Rf 14 Both are preferred if they contain fluorine atoms.

[0868] Specific examples of anions represented by equation (Xa-5) are shown below, but are not limited to these. Furthermore, in the following equation, X... BISame as above.

[0869] [Chemistry 313]

[0870]

[0871] [Chemical 314]

[0872]

[0873] [Chemical 315]

[0874]

[0875] [Chemistry 316]

[0876]

[0877] [Chemistry 317]

[0878]

[0879] [Chemistry 318]

[0880]

[0881] [Chemistry 319]

[0882]

[0883] [Chemistry 320]

[0884]

[0885] [Chemistry 321]

[0886]

[0887] [Chemistry 322]

[0888]

[0889] [Chemistry 323]

[0890]

[0891] [Chemistry 324]

[0892]

[0893] [Chemistry 325]

[0894]

[0895] [Chemistry 326]

[0896]

[0897] [Chemistry 327]

[0898]

[0899] [Chemistry 328]

[0900]

[0901] [Chemistry 329]

[0902]

[0903] [Chemistry 330]

[0904]

[0905] [Chemistry 331]

[0906]

[0907] [Chemistry 332]

[0908]

[0909] [Chemistry 333]

[0910]

[0911] [Chemistry 334]

[0912]

[0913] [Chemistry 335]

[0914]

[0915] 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 a mechanism that decomposes due to acid as described in International Publication No. 2021 / 200056 and Japanese Patent Application Publication No. 2021-70692, the anion with a cyclic ether group as described in Japanese Patent Application Publication No. 2018-180525 and Japanese Patent Application Publication No. 2021-35935, and the anion described in Japanese Patent Application Publication No. 2018-92159.

[0916] The aforementioned non-nucleophilic relative ions may also include the bulky benzenesulfonic acid derivative anions without fluorine atoms described in Japanese Patent Application Publication Nos. 2006-276759, 2015-117200, 2016-65016, and 2019-202974; the benzenesulfonic acid anions without fluorine atoms bonded to an aromatic group containing iodine atoms and the alkylsulfonic acid anions described in Japanese Patent No. 6645464.

[0917] The aforementioned non-nucleophilic relative ions may also include the anions of disulfonic acid described in Japanese Patent Application Publication No. 2015-206932, the anions of sulfonamides and sulfonamides with one side being sulfonic acid and the other side being different from it described in International Patent Application Publication No. 2020 / 158366, and the anions of sulfonic acid with one side being sulfonic acid and the other side being carboxylic acid described in Japanese Patent Application Publication No. 2015-24989.

[0918] Furthermore, component (D), i.e., photoacid generator, should preferably be represented by the following formula (5).

[0919] [Chemistry 336]

[0920]

[0921] In equation (5), R 201 and R 202 Each can be an independent hydrocarbon group with 1 to 30 carbon atoms, and may also contain heteroatoms. R 203 It can also contain a hydrocarbon group with 1 to 30 carbon atoms, which may also contain heteroatoms. Also, R 201 R 202 and R 203 Any two of them can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

[0922] R 201 and R 202 The hydrocarbon group represented has 1 to 30 carbon atoms and can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. Specific examples include alkyl groups with 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, tert-pentyl, n-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornel, oxanorbornel, and tricyclic [5.2.1.0] 2,6] Decyl, adamantyl, and other cyclic saturated hydrocarbon groups with 3 to 30 carbon atoms; phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, tert-butylnaphthyl, anthracene, and other aryl groups with 6 to 30 carbon atoms; groups obtained by combining these, etc. 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 can 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.

[0923] R 203 The derivatized hydrocarbon group representing 1 to 30 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, and hexadecane-1,16-diyl. Alkyl groups with 1 to 30 carbon atoms, such as heptadecanyl-1,17-diyl; cyclic saturated hydrocarbon groups with 3 to 30 carbon atoms, such as cyclopentanediyl, cyclohexanediyl, norcamphenediyl, and adamantanediyl; and aryl groups such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, and tert-butylnaphthylene. Furthermore, some or all of the hydrogen atoms in the aforementioned alkylene 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 alkylene group can be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. This results in the possible inclusion of hydroxyl, cyano, fluorine, chlorine, bromine, iodine, carbonyl, ether, ester, sulfonate, carbonate, lactone, sulfonate, carboxylic anhydride (-C(=O)-OC(=O)-), or haloalkyl groups. The aforementioned heteroatoms should preferably be oxygen atoms.

[0924] In equation (5), L 11It is a hydrocarbon group with 1 to 20 carbon atoms, which can be a single bond, an ether bond, or may contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed with R... 203 The same applies to the alkylene groups represented.

[0925] In equation (5), X a X b X c and X d Each can be independently a hydrogen atom, a fluorine atom, or a trifluoromethyl atom. However, X a X b X c and X d At least one of them is a fluorine atom or a trifluoromethyl atom.

[0926] The photoacid generator represented by formula (5) should preferably be represented by the following formula (5').

[0927] [Chemistry 337]

[0928]

[0929] In equation (5'), L 11 Same as above. X e It can be a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R 301 R 302 and R 303 Each hydrocarbon group consists independently of a hydrogen atom, or may contain heteroatoms, and has 1 to 20 carbon atoms. These hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be found in R in formula (Xa-1-1). fa1 The hydrocarbon groups represented are the same. s and t are each independently 0, 1, 2, 3, 4 or 5, and u is 0, 1, 2, 3 or 4.

[0930] The photoacid generator represented by formula (5) can be the same as that exemplified by the photoacid generator represented by formula (2) in Japanese Patent Application Publication No. 2017-26980.

[0931] Among the aforementioned photoacid generators, those containing anions represented by formula (Xa-1-1) or (Xa-4) exhibit low acid diffusion and excellent solubility in solvents, which is particularly desirable. Furthermore, those represented by formula (5') exhibit extremely low acid diffusion, which is also particularly desirable.

[0932] When the chemically amplified resist composition of the present invention includes (D) a photoacid generating agent, its content relative to 80 parts by weight of (A) the base polymer is preferably 0.1 to 40 parts by weight, and more preferably 0.5 to 20 parts by weight. If the amount of component (D), i.e., the photoacid generating agent, added is within the aforementioned range, the resolution is good, and there is no risk of foreign matter being generated after the resist film is developed or during peeling, which is ideal. (D) The photoacid generating agent can be used alone or in combination of two or more.

[0933] [(E) Surfactant]

[0934] The chemically amplified resist composition of the present invention may further include a surfactant as component (E). The surfactant (E) is preferably a surfactant that is insoluble or sparingly soluble in water but soluble in alkaline developing solution, or a surfactant that is insoluble or sparingly soluble in both water and alkaline developing solution. Such surfactants can be referred to in Japanese Patent Application Publication Nos. 2010-215608 and 2011-16746.

[0935] Regarding surfactants that are insoluble or poorly soluble in water and alkaline developing solutions, the surfactants described in the aforementioned announcement are preferably FC-4430 (manufactured by 3M), Surflon (registered trademark) S-381 (manufactured by AGC Seimichemical), Olfine (registered trademark) E1004 (manufactured by Nissin Chemical Industry), KH-20, KH-30 (manufactured by AGC Seimichemical), and oxobutane ring-opening polymers represented by the following formula (surf-1).

[0936] [Chemistry 338]

[0937]

[0938] Here, R, Rf, A, B, C, m, and n are not limited to the foregoing description, but only apply to formula (surf-1). R is an aliphatic group with 2 to 5 carbon atoms, ranging from 2 to 4 valences. Examples of the aforementioned aliphatic groups that are 2-valent include ethylene, 1,4-butylene, 1,2-propylene, 2,2-dimethyl-1,3-propylene, and 1,5-pentane, while examples of 3- or 4-valent groups include the following.

[0939] [Chemistry 339]

[0940]

[0941] In the formula, the dashed lines represent atomic bonds, which are partial structures derived from glycerol, trimethylolethane, trimethylolpropane, and neopentyl tertrol, respectively.

[0942] Among these, 1,4-butylene and 2,2-dimethyl-1,3-propylene are preferred.

[0943] Rf is trifluoromethyl or pentafluoroethyl, preferably trifluoromethyl. m is an integer from 0 to 3, n is an integer from 1 to 4, and the sum of n and m is the valence of R, which is an integer from 2 to 4. A is 1. B is an integer from 2 to 25, preferably an integer from 4 to 20. C is an integer from 0 to 10, preferably 0 or 1. Furthermore, the arrangement of the constituent units in formula (surf-1) is not limited; they can be block-bonded or randomly bonded. For details on the manufacture of surfactants based on partially fluorinated oxyheterocyclic butane ring-opening polymer systems, please refer to the specification of US Patent No. 5,650,483, etc.

[0944] Surfactants that are insoluble or sparingly soluble in water but soluble in alkaline developing solutions can reduce water penetration and leaching caused by their alignment with the surface of the resist film during ArF immersion photolithography without the use of a resist protective film. Therefore, they are useful for reducing damage to the exposure equipment by inhibiting the leaching of water-soluble components from the resist film. Furthermore, they are useful for developing alkaline solutions after exposure or post-exposure baking (PEB) to prevent the formation of foreign matter that could cause defects. Such surfactants, which are insoluble or sparingly soluble in water but soluble in alkaline developing solutions, are polymeric surfactants, also known as hydrophobic resins, and those with high water repellency that enhances hydrophobic properties are particularly desirable.

[0945] Specific examples of such polymeric surfactants include those containing at least one repeating unit selected from any of the following formulas (6A) to (6E).

[0946] [Transformation 340]

[0947]

[0948] In equations (6A) to (6E), R B It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. W 1 It can be -CH2-, -CH2CH2-, -O-, or two separate -H groups. R s1 Each is independently a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. R s2 It is a single bond, or a straight-chain or branched hydrocarbon group having 1 to 5 carbon atoms. R s3 Each is independently a hydrogen atom, a hydrocarbon group with 1 to 15 carbon atoms, a fluorinated hydrocarbon group, or an acid-labile group. R s3 When the group is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group can also be inserted between the carbon-carbon bonds. s4 It is a (w+1) valence hydrocarbon group or a fluorinated hydrocarbon group with 1 to 20 carbon atoms. w can be 1, 2, or 3. R s5Each is independently a hydrogen atom, or -C(=O)-OR sa The group indicated by R. sa It is a fluorinated hydrocarbon group with 1 to 20 carbon atoms. R s6 It is a hydrocarbon group or a fluorinated hydrocarbon group with 1 to 15 carbon atoms, and an ether bond or a carbonyl group may also be inserted between the carbon-carbon bonds.

[0949] R s1 The hydrocarbon group representing 1 to 10 carbon atoms should preferably be a saturated hydrocarbon group, and can be straight-chain, 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, those with 1 to 6 carbon atoms are preferred.

[0950] R s2 The alkylene group represented should preferably be a saturated alkylene group, and can be linear, branched, or cyclic. Specific examples include methylene, ethylene, propylene, butylene, and pentylene.

[0951] R s3 or R s6 The hydrocarbon group represented can be saturated or unsaturated, and can be straight-chain, branched, or cyclic. Specific examples include saturated hydrocarbon groups, alkenyl groups, alkynyl groups, and other aliphatic unsaturated hydrocarbon groups, with saturated hydrocarbon groups being preferable. The aforementioned saturated hydrocarbon groups, except for R... s1 Examples of hydrocarbon groups represented by R include undecyl, dodecyl, thiol, tetradecyl, and decadecyl groups. s3 or R s6 The fluorinated hydrocarbon group can be exemplified by groups in which some or all of the hydrogen atoms of the carbon atom bonded to the aforementioned hydrocarbon group are replaced by fluorine atoms. As mentioned earlier, ether bonds or carbonyl groups can also be inserted between these carbon-carbon bonds.

[0952] R s3 Specific examples of acid-instable groups include groups represented by the aforementioned formulas (AL-3) to (AL-5), trialkylsilyl groups with alkyl groups having 1 to 6 carbon atoms, and alkyl groups containing oxygen groups having 4 to 20 carbon atoms.

[0953] R s4 The (w+1) valence hydrocarbon group or fluorinated hydrocarbon group can be straight-chain, branched, or cyclic. Specific examples can be listed as groups obtained by removing w hydrogen atoms from the aforementioned hydrocarbon group or fluorinated hydrocarbon group.

[0954] R saThe fluorinated hydrocarbon group represented should preferably be saturated and can be linear, branched, or cyclic. Specific examples include those in which some or all of the hydrogen atoms of the aforementioned hydrocarbon group are replaced by fluorine atoms. Specific examples include trifluoromethyl, 2,2,2-trifluoroethyl, 3,3,3-trifluoro-1-propyl, 3,3,3-trifluoro-2-propyl, 2,2,3,3-tetrafluoropropyl, 1,1,1,3,3,3-hexafluoroisopropyl, 2,2,3,3,4,4,4-heptafluorobutyl, 2,2,3,3,4,4,5,5-octafluoropentyl, 2,2,3,3,4,4,5,5,6,6,7,7-decafluoroheptyl, 2-(perfluorobutyl)ethyl, 2-(perfluorohexyl)ethyl, 2-(perfluorooctyl)ethyl, 2-(perfluorodecyl)ethyl, etc.

[0955] Specific examples of repeating units represented by any of equations (6A) to (6E) can be listed below, but are not limited to these. Furthermore, in the following equations, R... B Same as above.

[0956] [Chemistry 341]

[0957]

[0958] [Chemistry 342]

[0959]

[0960] [Chemistry 343]

[0961]

[0962] [Chemistry 344]

[0963]

[0964] [Chemistry 345]

[0965]

[0966] [Chemistry 346]

[0967]

[0968] The aforementioned polymeric surfactant may also include repeating units other than those represented by formulas (6A) to (6E). Examples of other repeating units include repeating units derived from methacrylic acid, α-trifluoromethacrylic acid derivatives, etc. In polymeric surfactants, the content of repeating units represented by formulas (6A) to (6E) is preferably 20 mol% or more, more preferably 60 mol% or more, and even more preferably 100 mol% in total repeating units.

[0969] The Mw of the aforementioned polymeric surfactant is preferably 1,000 to 500,000, and more preferably 3,000 to 100,000. The Mw / Mn ratio is preferably 1.0 to 2.0, and more preferably 1.0 to 1.6.

[0970] Methods for synthesizing the aforementioned polymeric surfactants include polymerizing monomers containing unsaturated bonds, representing repeating units of formulas (6A) to (6E) and providing other repeating units as needed, in an organic solvent by adding a free radical initiator and heating. Examples of organic solvents used in polymerization include toluene, benzene, THF, diethyl ether, and dioxane. Examples of polymerization initiators include AIBN, 2,2'-azobis(2,4-dimethylpentanonitrile), dimethyl 2,2-azobis(2-methylpropionic acid), benzoyl peroxide, and lauroyl peroxide. The reaction temperature is preferably 50–100°C. The reaction time is preferably 4–24 hours. Acid-unstable groups can be directly introduced into the monomer, or they can be protected or partially protected after polymerization.

[0971] When synthesizing the aforementioned polymeric surfactants, known chain transfer agents such as dodecyl mercaptan and 2-mercaptoethanol can also be used to adjust the molecular weight. In this case, the amount of these chain transfer agents added relative to the total molar number of monomers to be polymerized is preferably 0.01 to 10 mol%.

[0972] When the chemically amplified resist composition of the present invention includes (E) a surfactant, its content relative to 80 parts by mass of (A) the base polymer is preferably 0.1 to 50 parts by mass, and more preferably 0.5 to 10 parts by mass. If the content of (E) surfactant is 0.1 parts by mass or more, the receding contact angle between the resist film surface and water will be sufficiently increased; if it is 50 parts by mass or less, the dissolution rate of the resist film surface to the developer will be low, and the height of the formed fine pattern will be sufficiently maintained. (E) surfactant can be used alone or in combination of two or more.

[0973] [(F) Other ingredients]

[0974] The chemically amplified resist composition of the present invention may also include, as other components in (F), compounds that decompose due to acid to produce acid (acid-increasing compounds), organic acid derivatives, fluorinated alcohols, and compounds with a solubility of Mw3000 or less that change due to the action of acid (solution inhibitors). The aforementioned acid-increasing compounds can be referred to in Japanese Patent Application Publication No. 2009-269953 or Japanese Patent Application Publication No. 2010-215608. When the aforementioned acid-increasing compounds are included, their content relative to 80 parts by mass of the base polymer in (A) is preferably 0 to 5 parts by mass, and more preferably 0 to 3 parts by mass. If the content is too high, it is difficult to control acid diffusion, and deterioration of resolvability and pattern shape will occur. The aforementioned organic acid derivatives, fluorinated alcohols, and solvent inhibitors can be referred to in Japanese Patent Application Publication No. 2009-269953 or Japanese Patent Application Publication No. 2010-215608.

[0975] [Pattern Formation Method]

[0976] The pattern forming method of the present invention includes the following steps: forming a resist film on a substrate using the aforementioned chemically amplified resist composition, exposing the aforementioned resist film to high-energy radiation, and developing the aforementioned exposed resist film using a developing solution.

[0977] The aforementioned substrate may be, for example, a substrate for integrated circuit manufacturing (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflective film, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, MoSi2, SiO2, etc.).

[0978] The resist film can be formed by, for example, coating the aforementioned chemically amplified resist composition onto a substrate with a preferred film thickness of 0.05 to 2 μm using a spin coating method, placing the substrate on a heating plate, preferably at 60 to 150°C for 1 to 10 minutes, more preferably at 80 to 140°C for 1 to 5 minutes.

[0979] High-energy rays used in the exposure of resist films include KrF excimer lasers, ArF excimer lasers, EB, and EUV with wavelengths of 3–15 nm. When using KrF excimer lasers, ArF excimer lasers, or EUV, a mask used to form the target pattern can be used, with an optimal exposure dose of 1–200 mJ / cm². 2 It is even better to achieve 10-100 mJ / cm 2 Irradiation is performed in this manner. When using EB, a mask used to form the target pattern can be used or directly, with an optimal exposure of 1–300 μC / cm. 2 It is better to achieve a temperature of 10–200 μC / cm 2Irradiation is performed in this manner.

[0980] Furthermore, in addition to the usual exposure method, an immersion method can be used, in which a liquid with a refractive index of 1.0 or higher is placed between the resist film and the projection lens. In this case, a water-insoluble protective film can also be used.

[0981] The aforementioned water-insoluble protective film, used to prevent leaching from the resist film and improve the hydrophobicity of the film surface, is broadly classified into two types. One type is an organic solvent-stripping type, which requires peeling with an organic solvent that does not dissolve the resist film before alkaline aqueous solution development. The other type is an alkaline aqueous solution-soluble type, which is soluble in alkaline developing solution and removes the soluble portion of the resist film while simultaneously removing the protective film. The latter is preferably a material based on a polymer containing 1,1,1,3,3,3-hexafluoro-2-propanol residues that are insoluble in water but soluble in alkaline developing solution, dissolved in alcohol solvents with 4 or more carbon atoms, ether solvents with 8 to 12 carbon atoms, or mixtures thereof. Alternatively, a material can be made by dissolving the aforementioned water-insoluble but alkaline developing solution-soluble surfactant in alcohol solvents with 4 or more carbon atoms, ether solvents with 8 to 12 carbon atoms, or mixtures thereof.

[0982] After exposure, PEB can also be performed. PEB can be performed, for example, by heating on a hot plate at a temperature of 60–150°C for 1–5 minutes, or more preferably at a temperature of 80–140°C for 1–3 minutes.

[0983] For example, a developing solution containing an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH) of preferably 0.1 to 5% by mass, more preferably 2 to 3% by mass, can be used. The developing process is carried out using conventional methods such as dip, immersion, or spraying, preferably for 0.1 to 3 minutes, more preferably 0.5 to 2 minutes. In this way, the exposed part dissolves, and the target pattern can be formed on the substrate.

[0984] Furthermore, after the resist film is formed, acid-generating agents and other particles from the film surface can be separated by rinsing with pure water, or washed off. It can also be used to remove water remaining on the film after exposure.

[0985] Furthermore, a double patterning method can also be used to form patterns. Examples of double patterning methods include the trench method, which uses a first exposure and etching to process a 1:3 trench pattern on a substrate, moves the substrate, and uses a second exposure to form a 1:3 trench pattern to form a 1:1 pattern; and the line method, which uses a first exposure and etching to process a 1:3 isolated residual pattern on a first substrate, moves the substrate, and uses a second exposure to process a second substrate on which a 1:3 isolated residual pattern has been formed under the first substrate to form a 1:1 pattern with a pitch of half.

[0986] In the pattern forming method of the present invention, a negative development method that uses an organic solvent to dissolve the unexposed portion can also be used instead of the aforementioned alkaline aqueous solution as the developer.

[0987] For the aforementioned organic solvent development, the following can be used as developing solutions: 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methyl acetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, methyl valerate, methyl valerate, methyl crotonate, croton... Ethyl propionate, methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenyl acetate, ethyl phenyl acetate, benzyl formate, phenyl ethyl formate, methyl 3-phenylpropionate, benzyl propionate, 2-phenylethyl acetate, etc. These organic solvents can be used alone or in mixtures of two or more.

[0988] Example

[0989] The present invention is illustrated below with examples of synthesis, embodiments, and comparative examples. However, the present invention is not limited to the embodiments described below. Furthermore, the apparatus used is as follows.

[0990] MALDI TOF-MS: S3000 manufactured by Nippon Electronics Co., Ltd.

[0991] [1] Synthesis of sulfonium salt monomers

[0992] [Example 1-1] Synthesis of monomer PAG-1

[0993] (1) Synthesis of intermediate In-1

[0994] [Chemistry 347]

[0995]

[0996] Under nitrogen atmosphere, SM-1 (27.9 g), SM-2 (89.5 g), and copper acetate (8.24 g) were dissolved in dichloroethane (300 g). The reaction mixture was then heated to 100 °C and matured for 15 hours. After maturation, the reaction mixture was cooled, and water (150 g) was added to stop the reaction. The organic layer was then separated and washed with water, followed by distillation under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography to obtain 53.8 g (82% yield) of a yellow, viscous, oily intermediate, In-1.

[0997] (2) Synthesis of monomer PAG-1

[0998] [Chemistry 348]

[0999]

[1000] Under nitrogen atmosphere, intermediates In-1 (36.1 g), In-2 (70.4 g), dichloromethane (300 g), and water (150 g) were added and stirred at room temperature for 30 minutes. The organic layer was separated and washed with water, followed by concentration under reduced pressure. The residue was washed with diisopropyl ether and concentrated to obtain 78.4 g (97% yield) of monomer PAG-1 in oily form.

[1001] The TOF-MS results for PAG-1 are shown below.

[1002] MALDI TOF-MS:POSITIVE M + 288 (equivalent to C) 19 H 14 NS + )

[1003] NEGATIVE M - 789 (equivalent to C) 18 H 10 F2I3O7S - )

[1004] [Examples 1-2 to 1-9] Synthesis of monomers PAG-2 to PAG-9

[1005] Using the corresponding raw materials and various organic synthesis reactions, the sulfonate monomers PAG-2 to PAG-9 shown below were synthesized.

[1006] [Chemistry 349]

[1007]

[1008] [Chemical 350]

[1009]

[1010] [Comparative Examples 1-1 to 1-6] Comparative Synthesis of Monomers PAG-A to PAG-F

[1011] Using the corresponding raw materials and various organic synthesis reactions, the comparative sulfonate monomers PAG-A to PAG-F shown below were synthesized.

[1012] [Chemistry 351]

[1013]

[1014] [2] Synthesis of basic polymers

[1015] The monomers used in the synthesis of the basic polymer, other than PAG-1 to PAG-9 and PAG-A to PAG-F, are as follows.

[1016] [Chemistry 352]

[1017]

[1018] [Chemistry 353]

[1019]

[1020] [Chemistry 354]

[1021]

[1022] [Example 2-1] Synthesis of Polymer P-1

[1023] Under nitrogen atmosphere, monomer-polymerization initiator solution was prepared by taking monomer a1-1 (19.2 g), monomer b1-1 (5.6 g), monomer PAG-1 (25.3 g), V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) 1.80 g, and MEK 70 g in a flask. In another flask under nitrogen atmosphere, MEK 23 g was taken, 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 polymerization solution was maintained at 80°C and stirred for another 2 hours, then cooled to room temperature. The obtained polymerization solution was added dropwise to 1000 g of hexane after vigorous stirring, and the precipitated polymer was filtered. The obtained polymer was then washed twice with 300 g of hexane and vacuum dried at 50°C for 20 hours to obtain a white powder polymer P-1 (yield 49.1 g, 98% yield). The Mw of polymer P-1 is 9700, and the Mw / Mn ratio is 1.61. Furthermore, Mw is a polystyrene equivalent value obtained by GPC using DMF as a solvent.

[1024] [Chemistry 355]

[1025]

[1026] [Examples 2-2 to 2-26, Comparative Examples 2-1 to 2-18] Synthesis of polymers P-2 to P-26 and CP-1 to CP-18

[1027] Except for changing the type and blending ratio of each monomer, the polymers shown in Tables 1 and 2 were manufactured using the same method as in Example 2-1.

[1028] [Table 1]

[1029]

[1030] [Table 2]

[1031]

[1032] [3] Preparation of chemically amplified resist composition

[1033] [Examples 3-1 to 3-26, Comparative Examples 3-1 to 3-18]

[1034] A solution was prepared by dissolving the base polymer (P-1 to P-26) containing the sulfonium salt monomers (PAG-1 to PAG-9) of the present invention, the base polymer (CP-1 to CP-18) containing the comparative sulfonium salt monomers (PAG-A to PAG-F), the photoacid generator (PAG-X, PAG-Y), and the quencher (Q-1 to Q-4) as shown in Tables 3 and 4 below in a solvent containing 0.01% by mass of surfactant A (OMNOVA). The solution was then filtered using a 0.2 μm Teflon (registered trademark) type filter to prepare the chemically amplified resist composition (R-1 to R-26, CR-1 to CR-18).

[1035] [Table 3]

[1036]

[1037] [Table 4]

[1038]

[1039] In Tables 3 and 4, the solvent, photoacid generators PAG-X and PAG-Y, quenchers Q-1 to Q-4, and surfactant A are as follows.

[1040] Solvent: PGMEA (Propylene Glycol Monomethyl Ether Acetate)

[1041] EL (ethyl lactate)

[1042] DAA (diacetone alcohol)

[1043] • Photoacid generators: PAG-X, PAG-Y

[1044] [Chemistry 356]

[1045]

[1046] Quenching agents: Q-1 to Q-4

[1047] [Chemistry 357]

[1048]

[1049] Surfactant A: 3-methyl-3-(2,2,2-trifluoroethoxymethyl)oxetane / tetrahydrofuran / 2,2-dimethyl-1,3-propanediol copolymer (manufactured by OMNOVA).

[1050] [Chemistry 358]

[1051]

[1052] a : (b + b') : (c + c') = 1 : 4 ~ 7 : 0.01 ~ 1 (molar ratio)

[1053] Mw = 1500

[1054] [4] Evaluation of EUV lithography (1)

[1055] [Examples 4-1 to 4-26, Comparative Examples 4-1 to 4-18]

[1056] The chemically amplified resist compositions (R-1 to R-26, CR-1 to CR-18) shown in Tables 3 and 4 were spin-coated onto a Si substrate with a 20 nm thick silicon-containing spin-coated hard mask SHB-A940 (43% by mass silicon) manufactured by Shin-Etsu Chemical Industry Co., Ltd. A 50 nm thick resist film was fabricated by pre-baking at 100°C for 60 seconds using a heated plate. The aforementioned resist film was then exposed using an ASML EUV scanning lithography machine NXE3400 (NA 0.33, σ 0.9 / 0.6, dipole illumination) to create an LS pattern with a wafer size of 18 nm and a pitch of 36 nm, while simultaneously varying the exposure dose and focal length (exposure dose pitch: 1 mJ / cm). 2 (Focal pitch: 0.020 μm) After exposure, PEB was performed for 60 seconds at the temperatures shown in Tables 5 and 6. Subsequently, immersion development was performed for 30 seconds with a 2.38% by mass TMAH aqueous solution, followed by rinsing with a surfactant-containing rinsing material and rotary drying to obtain a positive pattern.

[1057] The obtained LS patterns were observed using a Hitachi Advanced Semiconductor Critical Dimension SEM (CG6300), and the sensitivity, EL, LWR, depth of focus (DOF), and collapse limit were evaluated according to the methods described below. Furthermore, the development defects of the obtained LS patterns were evaluated. The results are shown in Tables 5 and 6.

[1058] [Sensitivity Evaluation]

[1059] The optimal exposure Eop (mJ / cm) for obtaining an LS pattern with a linewidth of 18nm and a pitch of 36nm was determined. 2 This value is defined as sensitivity. The smaller the value, the higher the sensitivity.

[1060] [EL Review]

[1061] The exposure amount formed within ±10% (16.2–19.8 nm) of the 18 nm spacing width in the aforementioned LS pattern is used to calculate the EL (in %) using the following formula. The larger this value, the better the performance.

[1062] EL(%)=(|E1-E2| / Eop)×100

[1063] E1: Provides optimal exposure for LS patterns with a linewidth of 16.2nm and a pitch of 36nm.

[1064] E2: Provides optimal exposure for LS patterns with a linewidth of 19.8nm and a pitch of 36nm.

[1065] Eop: Provides optimal exposure for LS patterns with a linewidth of 18nm and a pitch of 36nm.

[1066] [LWR Evaluation]

[1067] For the LS pattern obtained by Eop irradiation, the dimensions at 10 points along the length of the line are measured, and the standard deviation (σ) of the results is calculated as 3σ, which is taken as the LWR. The smaller this value, the more pattern with low roughness and uniform linewidth will be obtained.

[1068] [DOF Rating]

[1069] In terms of depth of focus evaluation, the focal length range is determined by the range of ±10% (16.2 to 19.8 nm) of the 18 nm dimension in the aforementioned LS pattern. The larger this value, the wider the depth of focus.

[1070] [Collapse Limit Assessment of Line Patterns]

[1071] The line dimensions of each exposure at the optimal focal length of the aforementioned LS pattern were measured along the length direction at 10 points. The finest line dimension obtained in the undamaged state was defined as the collapse limit dimension. The smaller this value, the better the collapse limit.

[1072] [Evaluation of Development Defects]

[1073] For an LS pattern with a linewidth of 18nm and a pitch of 36nm formed using the aforementioned optimal exposure, a defect detection device KLA2360 (trade name) manufactured by KLA Tencor was used. The pixel size of the defect detection device was set to 0.16μm, and the threshold was set to 20. Defects (number / cm) identified by comparing the difference between the image and the pixel unit overlap were detected. 2 The inspection is performed to calculate the number of defects per unit area (defects / cm²). 2 Subsequently, through defect assessment, development defects are categorized and isolated from all defects, and the number of development defects per unit area (defects / cm²) is calculated.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.

[1074] [Table 5]

[1075]

[1076] [Table 6]

[1077]

[1078] The results shown in Tables 5 and 6 demonstrate that the chemically amplified resist composition containing polymers derived from the sulfonate monomers of this invention exhibits good sensitivity, excellent EL, LWR, and DOF. Furthermore, a low collapse limit value was confirmed, indicating resistance to pattern collapse even during the formation of fine patterns. Moreover, it was confirmed that it also suppresses development defects. Therefore, the chemically amplified resist composition of this invention is suitable as a material for EUV lithography.

[1079] [5] Evaluation of EUV lithography (2)

[1080] [Examples 5-1 to 5-26, Comparative Examples 5-1 to 5-18]

[1081] The chemically amplified resist compositions (R-1 to R-26, CR-1 to CR-18) shown in Tables 3 and 4 were spin-coated onto a Si substrate with a silicon-containing spin-coated hard mask SHB-A940 (43% by mass) manufactured by Shin-Etsu Chemical Industry Co., Ltd., which had a film thickness of 20 nm. A resist film with a thickness of 50 nm was formed by pre-baking at 105°C for 60 seconds using a hot plate. The aforementioned resist film was exposed using an ASML EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.6, quadrupole illumination, mask with a pitch of 46 nm on the wafer, and a hole pattern with a deviation of +20%) and exposed to PEB at the temperatures described in Tables 7 and 8 for 60 seconds, followed by development with a 2.38% by mass TMAH aqueous solution for 30 seconds to form a hole pattern with a size of 23 nm.

[1082] Using a Hitachi Advanced Semiconductor Critical Dimension SEM (CG6300), the exposure required to form a hole size of 23 nm was measured and defined as the sensitivity. Furthermore, the size of 50 holes at this point was measured, and three times the standard deviation (σ) calculated from these results (3σ) was defined as the CDU. The results are shown in Tables 7 and 8.

[1083] [Table 7]

[1084]

[1085] [Table 8]

[1086]

[1087] The results shown in Tables 7 and 8 confirm that chemically amplified resist compositions containing polymers composed of sulfonium salt monomers of the present invention exhibit good sensitivity and excellent CDU.

[1088] [6] Evaluation of dry etching resistance

[1089] [Examples 6-1 to 6-26, Comparative Examples 6-1 to 6-18]

[1090] A polymer solution containing 2g of each of the polymers shown in Tables 1 and 2 (polymers P-1 to P-26 and comparative polymers CP-1 to CP-18) dissolved in 10g of cyclohexanone and filtered through a 0.2μm filter was spin-coated onto a Si substrate to form a film with a thickness of 300nm. The film was evaluated under the following conditions.

[1091] Etching experiments using CHF3 / CF4-based gases:

[1092] The thickness difference of the polymer film before and after etching was determined using the TE-8500P dry etching apparatus manufactured by Tokyo Power Technology Co., Ltd.

[1093] The etching conditions are as follows.

[1094]

[1095] In this evaluation, those with smaller film thickness differences, i.e., smaller reductions, exhibit higher etching resistance.

[1096] The results of dry etching resistance are shown in Tables 9 and 10.

[1097] [Table 9]

[1098]

[1099] [Table 10]

[1100]

[1101] The results shown in Tables 9 and 10 confirm that the polymer of the present invention has excellent dry etching resistance to CHF3 / CF4 gases.

Claims

1. A sulfonium salt type monomer, represented by the following formula (A), In the formula, p is 1, 2, or 3; n1 is 0 or 1; n2 is 1 or 2; and n3 is 0, 1, 2, or 3. However, when n1 is 0, then 1 ≤ n2 + n3 ≤ 5; and when n1 is 1, then 1 ≤ n2 + n3 ≤ 7. R 1 The R group can be a halogen atom, nitro group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms, a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms, a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms, or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When n3 is 2 or 3, each R group... 1 They can be the same or different, 2 Rs 1 They can also bond to each other and form rings together with the carbon atoms they are bonded to. R 2 The two R groups are halogen atoms or may contain heteroatoms and are hydrocarbon groups with 1 to 30 carbon atoms. When p is 1, the two R groups are... 2 They can be the same, or they can be different, and also, with S + Two of the three substituents in the bond can also bond to each other and form a ring together with the sulfur atoms they are bonded to. Z - It is a fluoroalkane sulfonic acid anion with an aromatic vinyl structure and an iodine atom.

2. The sulfonium salt type monomer according to claim 1, wherein it is represented by the following formula (A1), In the formula, p, n1~n3, R 1 and Z - As mentioned above, n4 is 0 or 1, n5 is 0, 1, 2, 3, 4 or 5. R 3 The radical can be a halogen atom, nitro group, hydroxyl group, carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When n5 is 2, 3, 4, or 5, each R... 3 They can be the same or different, 2 Rs 3 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

3. The sulfonium salt type monomer according to claim 1, wherein, Z - Let Z represent the anion. In the formula, m1 is 0 or 1, m2 is 0, 1, 2, 3 or 4, m3 is 0, 1, 2 or 3, m4 is 0 or 1, m5 is 0, 1, 2, 3 or 4, m6 is 0, 1, 2 or 3, m7 is 0 or 1, m8 is 1, 2, 3 or 4, m9 is 0, 1, 2 or 3, m10 is 0, 1, 2, 3 or 4, m11 is 0 or 1, and m12 is 0 or 1. However, when m1 is 0, then 0 ≤ m2 + m3 + m12 ≤ 4; when m1 is 1, then 0 ≤ m2 + m3 + m12 ≤ 6; when m4 is 0, then 0 ≤ m5 + m6 ≤ 4; when m4 is 1, then 0 ≤ m5 + m6 ≤ 6; when m7 is 0, then 0 ≤ m8 + m9 ≤ 5; when m7 is 1, then 0 ≤ m8 + m9 ≤ 7. Also, 1 ≤ m2 + m5 + m8 ≤ 4. R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 11 R 12 and R 13 Each group can be independently composed of a halogen atom other than an iodine atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxy group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon thio group with 1 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxycarbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When m3 is 2 or 3, each R... 11 They can be the same or different, 2 Rs 11 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m6 is 2 or 3, each R 12 They can be the same or different, 2 Rs 12 They can also bond to each other and form rings together with the carbon atoms they are bonded to. When m9 is 2 or 3, each R 13 They can be the same or different, 2 Rs 13 They can also bond to each other and form rings together with the carbon atoms they are bonded to. L A L B L C L D and L E Each bond can be independently a single bond, ether bond, ester bond, sulfonate bond, amide bond, sulfonamide bond, carbonate bond, or carbamate bond. X L1 and X L2 Each is an independent single bond, or may contain heteroatoms, consisting of 1 to 40 carbon-containing hydrocarbon groups. Q 1 and Q 2 Each is independently a hydrogen atom, a fluorine atom, or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. Q 3 and Q 4 Each is independently a fluorine atom or a fluorinated saturated hydrocarbon group having 1 to 6 carbon atoms. However, m11 and m12 cannot both be 0 at the same time, L A L B L C L D X L1 and X L2 It cannot be a single key at the same time.

4. A monomeric photoacid generator, comprising a sulfonium salt monomer according to any one of claims 1 to 3.

5. A polymer comprising repeating units from the monomeric photoacid generator according to claim 4.

6. The polymer according to claim 5, further comprising at least one selected from the repeating unit represented by formula (a1), the repeating unit represented by formula (a2), and the repeating unit represented by formula (a3). In the formula, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. X 1 It is a single bond, phenylene, naphthylene, or *-C(=O)-OX 11 - The phenylene or naphthylene group may also be substituted with a hydroxyl, nitro, cyano group, a saturated hydrocarbon group containing fluorine atoms with 1 to 10 carbon atoms, a saturated hydroxyl group containing fluorine atoms with 1 to 10 carbon atoms, or a halogen atom. X 11 It is a saturated hydrocarbon group, phenylene group, or naphthylene group having 1 to 10 carbon atoms. The saturated hydrocarbon group may also contain a hydroxyl group, an ether bond, an ester bond, or a lactone ring. X 2 It is a single bond or *-C(=O)-O-. * indicates an atomic bond with a carbon atom in the main chain. R 21 The R group can be a halogen atom, cyano group, hydroxyl group, nitro group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxygen group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When a1 is 2, 3, or 4, each R group... 21 They can be the same, or they can be different. AL 1 and AL 2 Each is an independent acid-labile group. a1 is 0, 1, 2, 3, or 4. In the formula, b1 is 0 or 1, and b2 is 0, 1, 2 or 3 when b1 is 0, and 0, 1, 2, 3, 4 or 5 when b1 is 1. R A It can be a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. X 3 These are single bonds, *-C(=O)-O-, or *-C(=O)-NH-, where * indicates an atomic bond with a carbon atom in the main chain. X 4 It can be a single bond, an aliphatic alkylene group having 1 to 4 carbon atoms, a carbonyl group, a sulfonyl group, or a combination thereof. X 5 and X 6 Each can be independently an oxygen atom or a sulfur atom, but X 4 and X 6 Bonded to adjacent carbon atoms in the aromatic ring, R 22 and R 23 Each is an independent hydrocarbon group consisting of 1 to 20 carbon atoms, or may contain heteroatoms; and R 22 and R 23 They can also bond to each other and form rings together with the carbon atoms they are bonded to. R 24 It may contain halogen atoms, hydroxyl groups, cyano groups, nitro groups, or hydrocarbon groups with 1 to 20 carbon atoms that may contain heteroatoms; hydrocarbon oxygen groups with 1 to 20 carbon atoms that may contain heteroatoms; hydrocarbon oxygen carbonyl groups with 2 to 20 carbon atoms that may contain heteroatoms; or hydrocarbon thio groups with 1 to 20 carbon atoms or -N(R) groups. 24A (R) 24B ), R 24A and R 24B Each is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms; when b2 is 2 or more, each R 24 They can be the same or different; multiple Rs 24 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

7. The polymer according to claim 5, further comprising at least one of the repeating units represented by formula (b1) and formula (b2). In the formula, R A Each is independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Y 1 It is a single bond or *-C(=O)-O-, where * indicates an atomic bond with a carbon atom in the main chain. R 31 It is a hydrogen atom, or a group containing at least one carbon atom selected from hydroxyl groups other than phenolic hydroxyl groups, cyano groups, carbonyl groups, carboxyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulcinolone rings, and carboxylic anhydrides (-C(=O)-OC(=O)-). R 32 The R group can be a halogen atom, carboxyl group, nitro group, cyano group, or a hydrocarbon group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon oxygen group with 1 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms; a hydrocarbon carbonyl oxygen group with 2 to 20 carbon atoms that may contain heteroatoms; or a hydrocarbon oxygen carbonyl group with 2 to 20 carbon atoms that may contain heteroatoms. When c2 is 2, 3, or 4, each R group... 32 They can be the same, or they can be different. c1 can be 1, 2, 3 or 4, and c2 can be 0, 1, 2, 3 or 4, but 1≤c1+c2≤5.

8. A chemically amplified resist composition comprising (A) a base polymer containing the polymer according to claim 5.

9. The chemically amplified resist composition according to claim 8 further comprises (B) an organic solvent.

10. The chemically amplified resist composition according to claim 8, further comprising (C) a quencher.

11. The chemically amplified resist composition according to claim 8, further comprising (D) a photoacid generator.

12. The chemically amplified resist composition according to claim 8, further comprising (E) a surfactant.

13. A method for forming a pattern, comprising the following steps: A resist film is formed on a substrate using the chemically amplified resist composition according to claim 8, the resist film is exposed to high-energy rays, and the exposed resist film is developed using a developer.

14. The pattern forming method according to claim 13, wherein, The high-energy rays are KrF excimer lasers, ArF excimer lasers, electron beams, or extreme ultraviolet rays with wavelengths of 3–15 nm.

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