Chemically amplified resist material and pattern formation method

Abstract

To provide a chemically amplified resist material which exhibits high sensitivity and improved LWR and CDU regardless of whether it is positive or negative, and a pattern forming method using the same.SOLUTION: The chemically amplified resist material contains a quencher and an acid generator. The quencher is a compound having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxy group substituted with an acid-labile group in the molecule.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a chemically amplified resist material and a pattern forming method. [Background technology]

[0002] With the increasing integration and speed of LSIs, the miniaturization of pattern rules is progressing rapidly. In particular, the expansion of the logic memory market due to the spread of smartphones is driving this miniaturization. As for cutting-edge miniaturization technologies, mass production of 7nm node devices using double patterning in ArF immersion lithography and mass production of 5nm node devices using extreme ultraviolet (EUV) lithography are currently underway.

[0003] As miniaturization progresses and approaches the diffraction limit of light, the contrast of light decreases. This decrease in light contrast leads to a reduction in the resolution of hole and trench patterns, as well as a decrease in the focus margin, in positive-type resist films. To prevent the decrease in resolution of resist patterns due to the decrease in light contrast, attempts are being made to improve the dissolution contrast of the resist film.

[0004] For chemically amplified positive-type resist materials that undergo an acid-induced deprotection reaction by adding an acid generator and irradiating them with light or electron beam (EB), and for chemically amplified negative-type resist materials that undergo an acid-induced polarity change reaction or crosslinking reaction, the addition of a quencher to control the diffusion of acid into unexposed areas and improve contrast has been very effective. As a result, many amine quenchers have been proposed (Patent Documents 1-3). Patent Document 3 describes a resist material containing an amine compound having a tertiary ester-type acid-unstable group. By deprotecting the acid-unstable group, the alkali dissolution rate of not only the base polymer but also the amine quencher is improved, resulting in improved dissolution contrast.

[0005] Resist materials for EB and EUV lithography, which require the formation of ultrafine patterns, need not only improved dissolution contrast but also unprecedented control of acid diffusion. The amine quenchers described in Patent Documents 1-3 lack sufficient acid diffusion control capabilities. There is a need to develop new materials that achieve low acid diffusion and high contrast. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2001-194776 [Patent Document 2] Japanese Patent Publication No. 2002-226470 [Patent Document 3] Japanese Patent Publication No. 2002-363148 [Overview of the project] [Problems that the invention aims to solve]

[0007] In acid-catalyzed chemically amplified resist materials, there is a need for the development of a quencher that can improve the edge roughness (LWR) of line patterns and the dimensional uniformity (CDU) of hole patterns, while also enhancing sensitivity. This requires further reducing the diffusion distance of the acid while simultaneously improving contrast, thus improving both conflicting properties.

[0008] This invention has been made in view of the above circumstances, and aims to provide a chemically amplified resist material that is highly sensitive and has improved LWR and CDU, whether it is positive or negative type, and a pattern formation method using the same. [Means for solving the problem]

[0009] As a result of diligent research to achieve the above objective, the inventors have discovered that by adding a compound having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group in its molecule as a quencher to a chemically amplified resist material containing an acid generator, a high acid diffusion control ability is obtained due to the synergistic effect of the nitro group and the heterocyclic amine structure, the dissolution contrast is improved by the deprotection of the acid-unstable group, film thinning after development is prevented, and in particular, the solubility of the exposed area is improved in positive-type resist materials, thereby obtaining a resist film with improved LWR and CDU, and thus completing the present invention.

[0010] In other words, the present invention provides the following chemically amplified resist material and pattern formation method. 1. A chemically amplified resist material comprising a quencher and an acid generator, wherein the quencher is a compound having in its molecule an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group. 2. A chemically amplified resist material of type 1, wherein the compound having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group in its molecule is represented by the following formula (1) or (2). [ka] (In the formula, m is 1 or 2, n1 is 1 or 2, and n2 is an integer between 0 and 3, where 1 ≤ n1 + n2 ≤ 4.) Circle R is a heterocycle with 3 to 12 carbon atoms containing the nitrogen atom in the formula, and may contain at least one selected from ether bonds, ester bonds, sulfide bonds, sulfonyl groups, and -N=. 1 The carbon atoms contained in the ring may bond with each other to form a bridged ring. Circle R' is a heterocycle with 3 to 12 carbon atoms containing a nitrogen atom in the formula, and includes ether bonds, ester bonds, sulfide bonds, sulfonyl groups, -N= and -N(R 1 )- may include at least one selected from the following. L is an ether bond, ester bond, amide bond, or thioester bond. X 1 and X 2 Each of these is independently a single bond or a saturated hydrocarbylene group having 1 to 20 carbon atoms, and the saturated hydrocarbylene group may contain at least one selected from ether bonds, ester bonds, and sulfide bonds. R 1 These are a hydrogen atom, a saturated hydrocarbyl group having 1 to 6 carbon atoms, an acetyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an n-propyloxycarbonyl group, an isopropyloxycarbonyl group, a tert-butoxycarbonyl group, a tert-pentyloxycarbonyl group, a methylcyclopentyloxycarbonyl group, an ethylcyclopentyloxycarbonyl group, a propylcyclopentyloxycarbonyl group, a phenyl group, a benzyl group, a naphthyl group, a naphthylmethyl group, a methylcyclohexyloxycarbonyl group, an ethylcyclohexyloxycarbonyl group, a 9-fluorenylmethyloxycarbonyl group, an allyloxycarbonyl group, a methoxymethyl group, an ethoxymethyl group, a propoxymethyl group, or a butoxymethyl group. R 2 This is a hydrogen atom, a halogen atom, a saturated hydrocarbyl group having 1 to 6 carbon atoms, or a phenyl group, and some or all of the hydrogen atoms of the saturated hydrocarbyl group or phenyl group may be substituted with halogen atoms. R 3 This is a hydrogen atom, a halogen atom, or a hydrocarbyl group having 1 to 10 carbon atoms. R 4 It is an acid-unstable group. 3. A chemically amplified resist material 1 or 2 wherein the acid generator generates sulfonic acid, imido acid, or methido acid. 4. Furthermore, one of the following chemically amplified resist materials (1-3) containing a base polymer. 5. A chemically amplified resist material of 4, wherein the base polymer contains a repeating unit represented by the following formula (a1) or a repeating unit represented by the following formula (a2). [ka] (In the formula, R A is independently a hydrogen atom or a methyl group.) R 11 and R 12 are independently acid-labile groups.) Y 1 is a linking group having 1 to 12 carbon atoms containing at least one selected from a single bond, a phenylene group, a naphthylene group, or an ester bond and a lactone ring.) Y 2 is a single bond or an ester bond.) 6. The chemically amplified resist material according to 5, which is a chemically amplified positive resist material.) 7. The chemically amplified resist material according to 4, wherein the base polymer does not contain an acid-labile group.) 8. The chemically amplified resist material according to 7, which is a chemically amplified negative resist material.) 9. The chemically amplified resist material according to any one of 4 to 8, wherein the base polymer contains a repeating unit represented by any of the following formulas (f1) to (f3). [Chemical formula] (In the formula, R A is independently a hydrogen atom or a methyl group.) Z 1 is a single bond, an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group having 7 to 18 carbon atoms obtained by combining these, or -O-Z 11 -, -C(=O)-O-Z 11 - or -C(=O)-NH-Z 11 -. Z 11 is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group having 7 to 18 carbon atoms obtained by combining these, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxy group.) Z 2 is a single bond, -Z 21 -C(=O)-O-, -Z 21 -O- or -Z 21 -O-C(=O)-. Z 21This is a saturated hydrocarbylene group having 1 to 12 carbon atoms, and may contain a carbonyl group, an ester bond, or an ether bond. Z 3 This includes single bonds, methylene groups, ethylene groups, phenylene groups, fluorinated phenylene groups, phenylene groups substituted with trifluoromethyl groups, -OZ 31 -, -C(=O)-OZ 31 -or -C(=O)-NH-Z 31 - is Z 31 This is a phenylene group substituted with an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a trifluoromethyl group, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. R 21 ~R 28 Each of these is independently a C1-C20 hydrocarbyl group which may contain a halogen atom or a heteroatom. 23 and R 24 or R 26 and R 27 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. R HF This is either a hydrogen atom or a trifluoromethyl group. M - (It is a non-nucleophilic counterion.) 10. Furthermore, one of the chemically amplified resist materials (1-9) containing an organic solvent. 11. Furthermore, one of the chemically amplified resist materials (1-10) containing a surfactant. A pattern formation method comprising the steps of: forming a resist film on a substrate using any of the chemically amplified resist materials described in 12.1 to 11; exposing the resist film with high-energy rays; and developing the exposed resist film using a developer. 13. Pattern formation method 12 wherein the high-energy ray is an i-line with a wavelength of 365 nm, an ArF excimer laser light with a wavelength of 193 nm, a KrF excimer laser light with a wavelength of 248 nm, an EB, or an EUV with a wavelength of 3 to 15 nm. [Effects of the Invention]

[0011] The quencher is a compound having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group in its molecule. Therefore, the coexistence of the nitro group and the amino group effectively suppresses acid diffusion, and the deprotection reaction of the acid-unstable group improves dissolution contrast. As a result, low acid diffusion and high contrast can be achieved, and the developed pattern is characterized by a low LWR and improved CDU. The quencher containing the compound is particularly effective in positive-type resist materials. [Modes for carrying out the invention]

[0012] [Chemically Amplified Resist Materials] The chemically amplified resist material of the present invention comprises a quencher containing a compound having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group in its molecule, and an acid generator. The compound neutralizes the acid generated from the acid generator and simultaneously generates a carboxylic acid through a deprotection reaction, thereby improving the alkali solubility of the exposed area. The nitro group has a high effect in suppressing acid diffusion, and in synergy with the heterocyclic amine structure in the molecule, it can exhibit high acid diffusion control ability. As a result, the diffusion distance of the acid is reduced while the dissolution contrast is improved, and a pattern with improved LWR and CDU can be formed after development.

[0013] The acid diffusion suppression effect, contrast enhancement effect, and LWR and CDU enhancement effect of the aforementioned compound are effective in both positive and negative pattern formation using alkaline aqueous solution development, as well as in negative pattern formation using organic solvent development.

[0014] [Quencher] The quencher contained in the chemical amplification resist material of the present invention includes a compound (hereinafter also referred to as compound A) having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group in its molecule. Compound A is particularly preferably represented by the following formula (1) or (2). [ka]

[0015] In equations (1) and (2), m is either 1 or 2. n1 is either 1 or 2. n2 is an integer between 0 and 3, where 1 ≤ n1 + n2 ≤ 4.

[0016] In formula (1), circle R is a heterocycle having 3 to 12 carbon atoms and containing the nitrogen atom in the formula, and may contain at least one selected from an ether bond, an ester bond, a sulfide bond, a sulfonyl group, and -N=. 1 The carbon atoms in the ring may bond to each other to form a bridged ring. In formula (2), circle R' is a heterocycle having 3 to 12 carbon atoms and containing the nitrogen atom in the formula, and may consist of an ether bond, an ester bond, a sulfide bond, a sulfonyl group, -N= and -N(R 1 )- may include at least one selected from the following.

[0017] The heterocycle having 3 to 12 carbon atoms and containing the nitrogen atom may be saturated or unsaturated, and may be monocyclic or polycyclic. In the case of polycyclic rings, fused rings or bridged rings are preferred. Specific examples of the heterocycle include aziridine rings, azirine rings, azetidine rings, azeto rings, pyrrolidine rings, pyrroline rings, pyrrole rings, piperidine rings, tetrahydropyridine rings, pyridine rings, azepane rings, azocane rings, azanorbornane rings, azaadamantane rings, tropane rings, quinuclidine rings, oxazolidine rings, thiazolidine rings, morpholine rings, thiomorpholine rings, pyrazolidine rings, imidazolidine rings, pyrazoline rings, imidazoline rings, pyrazole rings, imidazole rings, Triazole rings, tetrazole rings, pyrazine rings, triazine rings, indoline rings, indole rings, isoindole rings, pyrimidine rings, indoridine rings, benzimidazole rings, azaindole rings, azaindazole rings, purine rings, tetrahydroquinoline rings, tetrahydroisoquinoline rings, decahydroquinoline rings, decahydroisoquinoline rings, quinoline rings, isoquinoline rings, quinoxaline rings, phthalazine rings, quinazoline rings, sinnoline rings, carbazole rings, etc. are preferred.

[0018] In formulas (1) and (2), L is an ether bond, an ester bond, an amide bond, or a thioester bond.

[0019] In equations (1) and (2), X 1 and X 2 Each of these is independently a single bond or a saturated hydrocarbylene group having 1 to 20 carbon atoms, and the saturated hydrocarbylene group may contain at least one selected from ether bonds, ester bonds, and sulfide bonds. 1 As such, a single bond or a saturated hydrocarbylene group having 1 to 3 carbon atoms is preferred, X 2 A single bond is preferred.

[0020] In equations (1) and (2), R 1These are a hydrogen atom, a saturated hydrocarbyl group having 1 to 6 carbon atoms, an acetyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an n-propyloxycarbonyl group, an isopropyloxycarbonyl group, a tert-butoxycarbonyl group, a tert-pentyloxycarbonyl group, a methylcyclopentyloxycarbonyl group, an ethylcyclopentyloxycarbonyl group, a propylcyclopentyloxycarbonyl group, a phenyl group, a benzyl group, a naphthyl group, a naphthylmethyl group, a methylcyclohexyloxycarbonyl group, an ethylcyclohexyloxycarbonyl group, a 9-fluorenylmethyloxycarbonyl group, an allyloxycarbonyl group, a methoxymethyl group, an ethoxymethyl group, a propoxymethyl group, or a butoxymethyl group.

[0021] In equations (1) and (2), R 2 This is a hydrogen atom, a halogen atom, a saturated hydrocarbyl group having 1 to 6 carbon atoms, or a phenyl group, and some or all of the hydrogen atoms of the saturated hydrocarbyl group or phenyl group may be substituted with halogen atoms.

[0022] R 1 and R 2 The saturated hydrocarbyl group having 1 to 6 carbon atoms, represented by R, may be linear, branched, or cyclic. Specific examples include alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, 3-pentyl, tert-pentyl, neopentyl, and n-hexyl groups; and cyclic saturated hydrocarbyl groups having 3 to 6 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, cyclopropylethyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl, cyclohexylethyl, methylcyclopropyl, methylcyclobutyl, methylcyclopentyl, ethylcyclopropyl, and ethylcyclobutyl groups. 2Examples of halogen atoms represented by this formula include fluorine, chlorine, bromine, and iodine atoms.

[0023] In equations (1) and (2), R 3 R is a hydrogen atom, a halogen atom, or a hydrocarbyl group having 1 to 10 carbon atoms. 3 Examples of halogen atoms represented by R include fluorine, chlorine, bromine, and iodine atoms. 3The hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include C1-C10 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, 3-pentyl, tert-pentyl, neopentyl, n-hexyl, n-octyl, n-nonyl, and n-decyl; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, norbornyl, and cyclopropyl groups. Cyclopropylmethyl group, cyclopropylethyl group, cyclobutylmethyl group, cyclobutylethyl group, cyclopentylmethyl group, cyclopentylethyl group, cyclohexylmethyl group, cyclohexylethyl group, methylcyclopropyl group, methylcyclobutyl group, methylcyclopentyl group, methylcyclohexyl group, ethylcyclopropyl group, ethylcyclobutyl group, ethylcyclopentyl group, ethylcyclohexyl group, etc., cyclic saturated hydrocarbyl groups having 3 to 10 carbon atoms; vinyl group, 1-propene Alkenyl groups with 2 to 10 carbon atoms, such as nyl group, 2-propenyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, nonenyl group, and decenyl group; Alkynyl groups with 2 to 10 carbon atoms, such as ethynyl group, propynyl group, butynyl group, pentynyl group, hexynyl group, heptynyl group, octinyl group, noninyl group, and decinyl group; Cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group, ethylcyclopentenyl group, ethylcyclohexenyl group, norbol Examples include cyclic unsaturated aliphatic hydrocarbyl groups with 3 to 10 carbon atoms, such as the nenyle group; aryl groups with 6 to 10 carbon atoms, such as the phenyl group, methylphenyl group, ethylphenyl group, n-propylphenyl group, isopropylphenyl group, n-butylphenyl group, isobutylphenyl group, sec-butylphenyl group, tert-butylphenyl group, and naphthyl group; aralkyl groups with 7 to 10 carbon atoms, such as the benzyl group, phenethyl group, phenylpropyl group, and phenylbutyl group; and groups obtained by combining these.

[0024] In equations (1) and (2), R 4This is an acid-unstable group. Various acid-unstable groups can be selected, but examples include those represented by the following formulas (AL-1) to (AL-3). [ka] (In the equation, dashed lines represent connections.)

[0025] In equation (AL-1), a is an integer between 0 and 6. L1 This refers to a secondary or tertiary hydrocarbyl group having 4 to 20 carbon atoms, preferably 4 to 15 carbon atoms; a trihydrocarbylsilyl group in which each hydrocarbyl group is a saturated hydrocarbyl group having 1 to 6 carbon atoms; a carbonyl group; a saturated hydrocarbyl group having 4 to 20 carbon atoms including an ether bond or an ester bond; or a group represented by formula (AL-3). A secondary hydrocarbyl group refers to a group obtained by the removal of a hydrogen atom from a secondary carbon atom of a hydrocarbon, and a tertiary hydrocarbyl group refers to a group obtained by the removal of a hydrogen atom from a tertiary carbon atom of a hydrocarbon.

[0026] R L1 The secondary or tertiary hydrocarbyl group represented by may be saturated or unsaturated, and may be branched or cyclic. Specific examples include tert-butyl group, tert-pentyl group, 1,1-diethylpropyl group, 1-ethylcyclopentyl group, 1-butylcyclopentyl group, 1-ethylcyclohexyl group, 1-butylcyclohexyl group, 1-ethyl-2-cyclopentenyl group, 1-ethyl-2-cyclohexenyl group, and 2-methyl-2-adamantyl group. Examples of the trihydrocarbyl silyl group include trimethylsilyl group, triethylsilyl group, and dimethyl-tert-butylsilyl group. The saturated hydrocarbyl group containing the carbonyl group, ether bond, or ester bond may be linear, branched, or cyclic, but cyclic is preferred. Specific examples include 3-oxocyclohexyl group, 4-methyl-2-oxooxan-4-yl group, 5-methyl-2-oxooxolan-5-yl group, 2-tetrahydropyranyl group, and 2-tetrahydrofuranyl group.

[0027] Examples of acid-unstable groups represented by formula (AL-1) include tert-butoxycarbonyl group, tert-butoxycarbonylmethyl group, tert-pentyloxycarbonyl group, tert-pentyloxycarbonylmethyl group, 1,1-diethylpropyloxycarbonyl group, 1,1-diethylpropyloxycarbonylmethyl group, 1-ethylcyclopentyloxycarbonyl group, 1-ethylcyclopentyloxycarbonylmethyl group, 1-ethyl-2-cyclopentenyloxycarbonyl group, 1-ethyl-2-cyclopentenyloxycarbonylmethyl group, 1-ethoxyethoxycarbonylmethyl group, 2-tetrahydropyranyloxycarbonylmethyl group, and 2-tetrahydrofuranyloxycarbonylmethyl group.

[0028] Other acid-unstable groups represented by formula (AL-1) include those represented by the following formulas (AL-1)-1 to (AL-1)-10. [ka] (In the equation, dashed lines represent connections.)

[0029] In equations (AL-1)-1 to (AL-1)-10, a is the same as described above. L8 Each of these is independently a saturated hydrocarbyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. L9 R is a hydrogen atom or a saturated hydrocarbyl group having 1 to 10 carbon atoms. L10 This is a saturated hydrocarbyl group having 2 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. The saturated hydrocarbyl group may be linear, branched, or cyclic.

[0030] In formula (AL-2), R L2 and R L3Each of these is independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The saturated hydrocarbyl group may be linear, branched, or cyclic, and specific examples include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclopentyl group, cyclohexyl group, 2-ethylhexyl group, n-octyl group, and the like.

[0031] In formula (AL-2), R L4 This is a hydrocarbyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, which may contain heteroatoms. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. Examples of the hydrocarbyl group include saturated hydrocarbyl groups having 1 to 18 carbon atoms, and some of these hydrogen atoms may be substituted with hydroxyl groups, alkoxy groups, oxo groups, amino groups, alkylamino groups, etc. Examples of such substituted saturated hydrocarbyl groups are shown below. [ka] (In the equation, dashed lines represent connections.)

[0032] R L2 and R L3 And, R L2 and R L4 or R L3 and R L4 These atoms may bond with each other to form a ring together with the carbon atoms to which they are bonded, or together with a carbon atom and an oxygen atom, and in this case, R involved in ring formation L2 and R L3 , R L2 and R L4 , or R L3 and R L4 Each of these is an alkanediyl group having 1 to 18 carbon atoms, preferably 1 to 10. The number of carbon atoms in the ring obtained by bonding these is preferably 3 to 10, more preferably 4 to 10.

[0033] Among the acid-unstable groups represented by formula (AL-2), those that are linear or branched include, but are not limited to, those represented by formulas (AL-2)-1 to (AL-2)-69 below. In the following formulas, dashed lines represent bonds. [ka]

[0034] [ka]

[0035] [ka]

[0036] [ka]

[0037] Among the acid-unstable groups represented by formula (AL-2), cyclic groups include tetrahydrofuran-2-yl group, 2-methyltetrahydrofuran-2-yl group, tetrahydropyran-2-yl group, and 2-methyltetrahydropyran-2-yl group.

[0038] Furthermore, examples of acid-unstable groups include groups represented by the following formulas (AL-2a) or (AL-2b). The compound may be intermolecularly crosslinked by the acid-unstable group, or the base polymer described later may be intermolecularly or intramolecularly crosslinked. [ka] (In the equation, dashed lines represent connections.)

[0039] In formula (AL-2a) or (AL-2b), R L11 and R L12 Each of these is independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 8 carbon atoms. The saturated hydrocarbyl group may be linear, branched, or cyclic. Also, RL11 and R L12 These may bond with each other to form a ring with the carbon atoms to which they are bonded, in which case R L11 and R L12 These are, independently, alkanediyl groups having 1 to 8 carbon atoms. L13 Each of these is independently a saturated hydrocarbylene group having 1 to 10 carbon atoms. The saturated hydrocarbylene group may be linear, branched, or cyclic. Each of d and e is independently an integer from 0 to 10, preferably from 0 to 5, and f is an integer from 1 to 7, preferably from 1 to 3.

[0040] In formula (AL-2a) or (AL-2b), L A This is an aliphatic saturated hydrocarbon group having 1 to 50 carbon atoms with (f+1) valency, an alicyclic saturated hydrocarbon group having 3 to 50 carbon atoms with (f+1) valency, an aromatic hydrocarbon group having 6 to 50 carbon atoms with (f+1) valency, or a heterocyclic group having 3 to 50 carbon atoms with (f+1) valency. Furthermore, some of the -CH2- groups of these groups may be substituted with a group containing a heteroatom, and some of the hydrogen atoms bonded to the carbon atoms of these groups may be substituted with a hydroxyl group, a carboxyl group, an acyl group, or a fluorine atom. A Preferred examples include saturated hydrocarbon groups such as saturated hydrocarbylene groups, trivalent saturated hydrocarbon groups, and tetravalent saturated hydrocarbon groups having 1 to 20 carbon atoms, and arylene groups having 6 to 30 carbon atoms. The saturated hydrocarbon groups may be linear, branched, or cyclic. B These are -C(=O)-O-, -NH-C(=O)-O-, or -NH-C(=O)-NH-.

[0041] Examples of crosslinked acetal groups represented by formula (AL-2a) or (AL-2b) include groups represented by the following formulas (AL-2)-70 to (AL-2)-77. [ka] (In the equation, dashed lines represent connections.)

[0042] In formula (AL-3), R L5 , R L6 and RL7 is independently a hydrocarbyl group having 1 to 20 carbon atoms, and may contain heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, fluorine atom, etc. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include an alkyl group having 1 to 20 carbon atoms, a cyclic saturated hydrocarbyl group having 3 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, a cyclic unsaturated aliphatic hydrocarbyl group having 3 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, etc. Also, R L5 and R L6 and, R L5 and R L7 and, or R L6 and R L7 and may combine with each other to form an alicyclic ring having 3 to 20 carbon atoms together with the carbon atoms to which they are attached.

[0043] Examples of the group represented by formula (AL-3) include tert-butyl group, 1,1-diethylpropyl group, 1-ethylnorbornyl group, 1-methylcyclopentyl group, 1-ethylcyclopentyl group, 1-isopropylcyclopentyl group, 1-methylcyclohexyl group, 2-(2-methyl)adamantyl group, 2-(2-ethyl)adamantyl group, tert-pentyl group, etc.

[0044] Also, examples of the group represented by formula (AL-3) include groups represented by the following formulas (AL-3)-1 to (AL-3)-19.

Chemical formula

[0045] In formulas (AL-3)-1 to (AL-3)-19, R L14 is independently a saturated hydrocarbyl group having 1 to 8 carbon atoms or an aryl group having 6 to 20 carbon atoms. R L15 and R L17 are independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 20 carbon atoms. R L16is an aryl group having 6 to 20 carbon atoms. The saturated hydrocarbyl group may be linear, branched or cyclic. Further, as the aryl group, a phenyl group or the like is preferable. R F is a fluorine atom or a trifluoromethyl group. g is an integer of 1 to 5.

[0046] Furthermore, as the acid-labile group, a group represented by the following formula (AL-3)-20 or (AL-3)-21 can be mentioned. By the acid-labile group, the compound may be intermolecularly crosslinked, and the base polymer described later may be intermolecularly or intramolecularly crosslinked. [Chemical formula] (In the formula, the dashed line is a bond.)

[0047] In formula (AL-3)-20 and (AL-3)-21, R L14 is the same as described above. R L18 is a (h + 1)-valent saturated hydrocarbylene group having 1 to 20 carbon atoms, a (h + 1)-valent unsaturated aliphatic hydrocarbylene group having 2 to 20 carbon atoms or a (h + 1)-valent arylene group having 6 to 20 carbon atoms, and may contain heteroatoms such as an oxygen atom, a sulfur atom and a nitrogen atom. The saturated hydrocarbylene group may be linear, branched or cyclic. h is an integer of 1 to 3.

[0048] R 4Examples of acid-unstable groups represented by this include those described in Japanese Patent Publication No. 3832564, No. 5407892, No. 5407941, No. 5434983, No. 5463963, No. 5564293, No. 5565293, No. 5573595, No. 5655754, No. 5655755, and No. 5655756. In addition, acid-unstable groups containing aromatic groups or multiple bonds as described in Japanese Patent Publication No. 5772760, Japanese Unexamined Patent Publication No. 2007-279699, Japanese Unexamined Patent Publication No. 2018-172640, Japanese Unexamined Patent Publication No. 2019-214554, Japanese Unexamined Patent Publication No. 2021-50307 and Japanese Unexamined Patent Publication No. 2021-110922, as well as acid-unstable groups having a steroid structure as described in Japanese Patent Publication No. 6411967, can also be used.

[0049] Examples of compound A include, but are not limited to, those listed below. Note that in the following formula, R 1 and R 4 This is the same as described above. [ka]

[0050] [ka]

[0051] [ka]

[0052] [ka]

[0053] [ka]

[0054] [ka]

[0055]

change

[0056]

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[0057]

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[0058]

change

[0059]

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[0060]

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[0061]

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[0062]

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[0063]

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[0064]

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[0065] Compound A contains an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group within its molecule. Therefore, it can achieve low acid diffusion and high contrast through the acid-trapping ability of the heterocyclic amine structure via acid neutralization reactions, the acid diffusion control ability of the nitro group, and the acid-deprotection reaction of the acid-unstable group. This makes it possible to improve LWR or CDU.

[0066] A method for synthesizing compound A may include, for example, reacting phthalic anhydride having a nitro group with a cyclic amine compound having a hydroxyl group with a tertiary or secondary alcohol for forming an acid-unstable ester.

[0067] In the chemically amplified resist material of the present invention, the content of the quencher consisting of compound A is preferably 0.001 to 50 parts by mass, and more preferably 0.01 to 20 parts by mass, relative to 100 parts by mass of the base polymer described later, from the viewpoint of sensitivity and acid diffusion suppression effect. Compound A may be used alone or in combination of two or more types.

[0068] The quencher may include quenchers other than compound A (hereinafter referred to as "other quenchers"). Examples of other quenchers include conventional basic compounds. Examples of conventional basic compounds include primary, secondary, or tertiary aliphatic amines, hybrid amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxyl group, nitrogen-containing compounds having a sulfonyl group, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amides, imides, carbamates, etc. Particularly preferred are primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Publication No. 2008-111103, especially amine compounds having a hydroxyl group, ether bond, ester bond, lactone ring, cyano group, or sulfonic acid ester bond, or compounds having a carbamate group described in Japanese Patent Publication No. 3790649. By adding such basic compounds, it is possible to further suppress the diffusion rate of acids in the resist film or correct its shape, for example.

[0069] Other quenchers include the polymer-type quencher described in Japanese Patent Publication No. 2008-239918. This enhances the rectangularity of the resist pattern by oriented on the surface of the resist film. Polymer-type quenchers also have the effect of preventing film thinning of the pattern and rounding of the pattern top when a protective film for immersion lithography is applied.

[0070] In addition, sulfonium salts, iodonium salts, or ammonium salts may be added as other quenchers. In this case, suitable sulfonium salts, iodonium salts, or ammonium salts added as quenchers are salts of carboxylic acids, sulfonic acids, alkoxides, sulfonimides, or saccharins. The carboxylic acid in this case may or may not have fluorinated at the α-position.

[0071] Examples of such quenchers include compounds represented by the following formula (q1) (onium salts of sulfonic acids with the α-position not fluorinated), compounds represented by the following formula (q2) (onium salts of carboxylic acids), and compounds represented by the following formula (q3) (onium salts of alkoxides). [ka]

[0072] In formula (q1), R q1 This refers to a hydrocarbyl group having 1 to 40 carbon atoms, which may contain a hydrogen atom or a heteroatom, but excludes those in which the hydrogen atom bonded to the α-carbon atom of the sulfo group is substituted with a fluorine atom or a fluoroalkyl group.

[0073] R q1 The C1-C40 hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include C1-C40 alkyl groups 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, norbornyl, and tricyclo[5.2.1.0 2,6] Cyclic saturated hydrocarbyl groups with 3 to 40 carbon atoms, such as decanyl group, adamantyl group, and adamantylmethyl group; alkenyl groups with 2 to 40 carbon atoms, such as vinyl group, allyl group, propenyl group, butenyl group, and hexenyl group; cyclic unsaturated aliphatic hydrocarbyl groups with 3 to 40 carbon atoms, such as cyclohexenyl group; phenyl group, naphthyl group, alkylphenyl group (2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-methylmethylphenyl group, 4-methylphenyl group, methylphenyl group, methylphenyl group, 4-methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, methylphenyl group, Examples include aryl groups with 6 to 40 carbon atoms, such as t-butylphenyl group, 4-n-butylphenyl group, dialkylphenyl group (2,4-dimethylphenyl group, 2,4,6-triisopropylphenyl group, etc.), alkylnaphthyl group (methylnaphthyl group, ethylnaphthyl group, etc.), and dialkylnaphthyl group (dimethylnaphthyl group, diethylnaphthyl group, etc.); and aralkyl groups with 7 to 40 carbon atoms, such as benzyl group, 1-phenylethyl group, and 2-phenylethyl group.

[0074] Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. Examples of hydrocarbyl groups containing heteroatoms include heteroaryl groups such as thienyl groups; alkoxyphenyl groups such as 4-hydroxyphenyl, 4-methoxyphenyl, 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 4-tert-butoxyphenyl, and 3-tert-butoxyphenyl groups; alkoxynaphthyl groups such as methoxynaphthyl, ethoxynaphthyl, n-propoxynaphthyl, and n-butoxynaphthyl groups; dialkoxynaphthyl groups such as dimethoxynaphthyl and diethoxynaphthyl groups; and aryloxoalkyl groups such as 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl groups.

[0075] In formula (q2), R q2 R is a hydrocarbyl group having 1 to 40 carbon atoms, which may contain heteroatoms. q2 The hydrocarbyl group represented by R is q1 Examples of hydrocarbyl groups represented by the same formulas as those exemplified above include the following. Other specific examples include fluorine-containing alkyl groups such as trifluoromethyl group, trifluoroethyl group, 2,2,2-trifluoro-1-methyl-1-hydroxyethyl group, and 2,2,2-trifluoro-1-(trifluoromethyl)-1-hydroxyethyl group; and fluorine-containing aryl groups such as pentafluorophenyl group and 4-trifluoromethylphenyl group.

[0076] In equation (q3), R q3The group is a linear, branched, or cyclic alkyl or aryl group having 1 to 8 carbon atoms, and may have at least three fluorine atoms and a nitro group.

[0077] In equations (q1), (q2), and (q3), MQ + This is an onium cation. The onium cation is preferably a sulfonium cation, iodonium cation, or ammonium cation, and more preferably a sulfonium cation. An example of a sulfonium cation is the sulfonium cation described in Japanese Patent Publication No. 2017-219836.

[0078] As a quencher, a sulfonium salt of an iodized benzene ring-containing carboxylic acid represented by the following formula (q4) can also be suitably used. [ka]

[0079] In formula (q4), R q11 This may be a saturated hydrocarbyl group having 1 to 6 carbon atoms, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms, or a saturated hydrocarbylsulfonyloxy group having 1 to 4 carbon atoms, or -N(R q11A )-C(=O)-R q11B Or -N(R q11A )-C(=O)-OR q11B That is. R q11A R is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. q11B This is a saturated hydrocarbyl group having 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbyl group having 2 to 8 carbon atoms.

[0080] In equation (q4), x' is an integer between 1 and 5. y' is an integer between 0 and 3. z' is an integer between 1 and 3. L 11This is a single bond or a (z'+1) valence linking group having 1 to 20 carbon atoms, and may contain at least one selected from an ether bond, carbonyl group, ester bond, amide bond, sultone ring, lactam ring, carbonate bond, halogen atom, hydroxyl group, and carboxyl group. The saturated hydrocarbyl group, saturated hydrocarbyloxy group, saturated hydrocarbylcarbonyloxy group, and saturated hydrocarbylsulfonyloxy group may be linear, branched, or cyclic. When y' and / or z' is 2 or more, each R q11 They may be the same or different from one another.

[0081] In formula (q4), R q12 , R q13 and R q14 Each of these is a hydrocarbyl group having 1 to 20 carbon atoms, which may independently contain a halogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3) described later. 101 ~R 103 Examples of hydrocarbyl groups represented by are similar to those exemplified. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a hydroxyl group, carboxyl group, halogen atom, oxo group, cyano group, nitro group, sultone ring, sulfo group, or sulfonium salt-containing group, and some of the -CH2- of the hydrocarbyl group may be substituted with an ether bond, ester bond, carbonyl group, amide bond, carbonate bond, or sulfonic acid ester bond. Also, R q12 and R q13 These may bond with each other to form a ring with the sulfur atom to which they are bonded.

[0082] Specific examples of compounds represented by formula (q4) include those described in Japanese Patent Publication No. 2017-219836 and Japanese Patent Publication No. 2021-91666.

[0083] If the chemically amplified resist material of the present invention contains other quenchers, their content is preferably 0 to 5 parts by mass, and more preferably 0 to 4 parts by mass, per 100 parts by mass of the base polymer described later. The other quenchers may be used individually or in combination of two or more.

[0084] [Acid Generator] The chemically amplified resist material of the present invention includes an acid generator. The acid generator may be an additive-type acid generator different from the quencher and the components described later, and may also function as a base polymer as described later, in other words, a polymer-bound type acid generator that also functions as a base polymer.

[0085] As an additive-type acid generator, a compound that generates acid in response to active light or radiation (photoacid generator) is preferred. Any compound that generates acid upon irradiation with high-energy rays can be used as the photoacid generator, but those that generate sulfonic acid, imido acid, or methidic acid are preferred. Suitable photoacid generators include sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate type acid generators, etc. Specific examples of photoacid generators are those described in paragraphs

[0122] to

[0142] of Japanese Patent Publication No. 2008-111103.

[0086] Furthermore, a photoacid generator represented by the following formula (3) can also be suitably used. [ka]

[0087] In formula (3), R 101 ~R 103 Each of these is independently a C1-C20 hydrocarbyl group which may contain a halogen atom or a heteroatom.

[0088] Examples of the halogen atoms mentioned above include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0089] R 101 ~R 103 The hydrocarbyl group, represented by , having 1 to 20 carbon atoms, may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include C1-C20 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecyl, octadecyl, nonadecyl, and eicosyl; C3-C20 cyclic saturated hydrocarbyl groups such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, and adamantyl; C2-C20 alkenyl groups such as vinyl, propenyl, butenyl, and hexenyl; and ethynyl groups. Examples include alkynyl groups with 2 to 20 carbon atoms, such as propynyl and butynyl groups; cyclic unsaturated aliphatic hydrocarbyl groups with 3 to 20 carbon atoms, such as cyclohexenyl and norbornenyl groups; aryl groups with 6 to 20 carbon atoms, such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, and tert-butylnaphthyl groups; aralkyl groups with 7 to 20 carbon atoms, such as benzyl and phenethyl groups; and groups obtained by combining these.

[0090] Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a mercapto group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0091] Also, R 101 and R 102 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. In this case, the ring is preferably structured as shown below. [ka] (In the formula, the dashed line represents R 103 (This is a combination of the two.)

[0092] Examples of cations of the sulfonium salt represented by formula (3) include, but are not limited to, those listed below. [ka]

[0093] [ka]

[0094] [ka]

[0095] [ka]

[0096]

change

[0097]

change

[0098]

change

[0099]

change

[0100]

change

[0101]

change

[0102]

change

[0103]

change

[0104]

change

[0105]

change

[0106]

change

[0107]

Chem.

[0108]

Chem.

[0109]

Chem.

[0110]

Chem.

[0111]

Chem.

[0112]

Chem.

[0113]

Chem.

[0114]

Chem.

[0115]

Chem.

[0116] In formula (3), Xa - is an anion selected from the following formulas (3A) to (3D).

Chem.

[0117] In formula (3A), R fa R is a hydrocarbyl group having 1 to 40 carbon atoms, which may contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3A') described later. 111 Examples of hydrocarbyl groups represented by the symbol shown are similar to those exemplified.

[0118] The anion represented by formula (3A) is preferably the one represented by formula (3A') below. [ka]

[0119] In formula (3A'), R HF R is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. 111 This is a hydrocarbyl group having 1 to 38 carbon atoms, which may contain heteroatoms. The heteroatoms are preferably oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms, etc., with oxygen atoms being more preferred. The hydrocarbyl group is particularly preferred to have 6 to 30 carbon atoms in order to obtain high resolution in fine pattern formation.

[0120] R 111The hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups having 1 to 38 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, heptadecyl, and eicosanyl; cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, and norbornyl. Examples include cyclic saturated hydrocarbyl groups with 3 to 38 carbon atoms, such as norbornylmethyl group, tricyclodecanyl group, tetracyclododecanyl group, tetracyclododecanylmethyl group, and dicyclohexylmethyl group; unsaturated aliphatic hydrocarbyl groups with 2 to 38 carbon atoms, such as allyl group and 3-cyclohexenyl group; aryl groups with 6 to 38 carbon atoms, such as phenyl group, 1-naphthyl group, and 2-naphthyl group; aralkyl groups with 7 to 38 carbon atoms, such as benzyl group and diphenylmethyl group; and groups obtained by combining these.

[0121] Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. Examples of hydrocarbyl groups containing heteroatoms include tetrahydrofuryl group, methoxymethyl group, ethoxymethyl group, methylthiomethyl group, acetamidomethyl group, trifluoroethyl group, (2-methoxyethoxy)methyl group, acetoxymethyl group, 2-carboxy-1-cyclohexyl group, 2-oxopropyl group, 4-oxo-1-adamantyl group, and 3-oxocyclohexyl group.

[0122] Regarding the synthesis of sulfonium salts containing anions represented by formula (3A'), it is detailed in JP-A-2007-145797, JP-A-2008-106045, JP-A-2009-7327, JP-A-2009-258695, etc. In addition, sulfonium salts described in JP-A-2010-215608, JP-A-2012-41320, JP-A-2012-106986, JP-A-2012-153644, etc. are also preferably used.

[0123] Examples of the anion represented by formula (3A) include, but are not limited to, those shown below. In the following formulas, Ac is an acetyl group.

Chemical formula

[0124]

Chemical formula

[0125]

Chemical formula

[0126]

Chemical formula

[0127] In formula (3B), R fb1 and R fb2 are each independently a hydrocarbyl group having 1 to 40 carbon atoms which may contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include the same ones as those exemplified as the hydrocarbyl group represented by R 111 in formula (3A'). Preferably, R fb1 and R fb2 are a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fb1 and R fb2This refers to the groups that bond to each other (-CF2-SO2-N - It may form a ring with -SO2-CF2-), in which case R fb1 and R fb2 The group obtained by the bonding of these two elements is preferably a fluorinated ethylene group or a fluorinated propylene group.

[0128] In formula (3C), R fc1 , R fc2 and R fc3 Each of these is a hydrocarbyl group having 1 to 40 carbon atoms, which may independently contain a fluorine atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3A'). 111 Examples of hydrocarbyl groups represented by R include those similar to those exemplified. fc1 , R fc2 and R fc3 Preferably, R is a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. fc1 and R fc2 This refers to the groups that bond to each other (-CF2-SO2-C - It may form a ring with -SO2-CF2-), in which case R fc1 and R fc2 The group obtained by the bonding of these two elements is preferably a fluorinated ethylene group or a fluorinated propylene group.

[0129] In formula (3D), R fd R is a hydrocarbyl group having 1 to 40 carbon atoms, which may contain heteroatoms. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3A'). 111 Examples of hydrocarbyl groups represented by the same formula as those exemplified above include those shown.

[0130] The synthesis of sulfonium salts containing the anion represented by formula (3D) is detailed in Japanese Patent Publication No. 2010-215608 and Japanese Patent Publication No. 2014-133723.

[0131] The anions represented by formula (3D) include, but are not limited to, those listed below. [ka]

[0132] [ka]

[0133] Furthermore, the photoacid generator containing the anion represented by formula (3D) does not have a fluorine atom at the α-position of the sulfo group, but has two trifluoromethyl groups at the β-position, which gives it sufficient acidity to cleave acid-unstable groups in the base polymer. Therefore, it can be used as a photoacid generator.

[0134] As a photoacid generator, one represented by the following formula (4) can also be suitably used. [ka]

[0135] In formula (4), R 201 and R 202 Each of these is independently a hydrocarbyl group having 1 to 30 carbon atoms, which may contain a halogen atom or a heteroatom. 203 This is a hydrocarbylene group having 1 to 30 carbon atoms, which may contain heteroatoms. Also, R 201 , R 202 and R 203 Any two of these may bond with each other to form a ring with the sulfur atom to which they are bonded. In this case, the ring is defined as R in the explanation of formula (3). 101 and R 102 Examples of rings that can be formed when these elements combine with the sulfur atom to which they are bonded are similar to those exemplified.

[0136] R 201 and R 202The hydrocarbyl group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include alkyl groups having 1 to 30 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, norbornyl, oxanorbornyl, and tricyclo[5.2.1.0 2,6 Examples include cyclic saturated hydrocarbyl groups having 3 to 30 carbon atoms, such as decanyl and adamantyl groups; aryl groups having 6 to 30 carbon atoms, such as 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, and anthracenyl groups; and groups obtained by combining these. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0137] R 203The hydrocarbylene group represented by may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include alkane diyl groups with 1 to 30 carbon atoms, such as methanediyl group, ethane-1,1-diyl group, ethane-1,2-diyl group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1,17-diyl group, etc.; cyclopentanediyl group, cyclohex Examples include cyclic saturated hydrocarbylene groups having 3 to 30 carbon atoms, such as xanediyl, norbornanediyl, and adamantanediyl groups; arylene groups having 6 to 30 carbon atoms, 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; and groups obtained by combining these. Furthermore, some or all of the hydrogen atoms of the hydrocarbylene group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, nitrogen atom, or halogen atom, and some of the -CH2- of the hydrocarbylene group may be substituted with a group containing a heteroatom such as an oxygen atom, sulfur atom, or nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. The heteroatom is preferably an oxygen atom.

[0138] In formula (4), L AThis is a 1-20 carbon atom hydrocarbylene group which may contain single bonds, ether bonds, or heteroatoms. The hydrocarbylene group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R 203 Examples of hydrocarbylene groups represented by the same formula as those exemplified above include the same groups as those shown.

[0139] In formula (4), X A , X B , X C and X D Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group. However, X A , X B , X C and X D At least one of these is a fluorine atom or a trifluoromethyl group.

[0140] In equation (4), k is an integer between 0 and 3.

[0141] As the photoacid generator represented by formula (4), the one represented by the following formula (4') is preferred. [ka]

[0142] In formula (4'), L A The same as above. R HF R is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. 301 , R 302 and R 303 Each of these is independently a hydrocarbyl group having 1 to 20 carbon atoms, which may contain a hydrogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3A'). 111 Examples of hydrocarbyl groups represented by the formula shown are similar to those exemplified. x and y are each independent integers from 0 to 5, and z is an integer from 0 to 4.

[0143] Examples of photoacid generators represented by formula (4) include those similar to those exemplified as photoacid generators represented by formula (2) in Japanese Patent Publication No. 2017-026980.

[0144] Among the photoacid generators, those containing an anion represented by formula (3A') or (3D) are particularly preferred because they exhibit low acid diffusion and excellent solubility in solvents. Furthermore, those represented by formula (4') are particularly preferred because they exhibit extremely low acid diffusion.

[0145] As the photoacid generator, a sulfonium salt or iodonium salt containing an anion having an aromatic ring substituted with an iodine or bromine atom can also be used. Examples of such salts are those represented by the following formulas (5-1) or (5-2). [ka]

[0146] In equations (5-1) and (5-2), p is an integer satisfying 1 ≤ p ≤ 3. q and r are integers satisfying 1 ≤ q ≤ 5, 0 ≤ r ≤ 3, and 1 ≤ q + r ≤ 5. q is preferably an integer satisfying 1 ≤ q ≤ 3, and more preferably 2 or 3. r is preferably an integer satisfying 0 ≤ r ≤ 2.

[0147] In equations (5-1) and (5-2), X BI These atoms are iodine atoms or bromine atoms, and when p and / or q are 2 or greater, they may be the same or different from each other.

[0148] In equations (5-1) and (5-2), L 1 This is a saturated hydrocarbylene group having 1 to 6 carbon atoms, which may contain a single bond, an ether bond, or an ester bond, or an ether bond or an ester bond. The saturated hydrocarbylene group may be linear, branched, or cyclic.

[0149] In equations (5-1) and (5-2), L 2When p is 1, it is a single bond or a divalent linking group having 1 to 20 carbon atoms, and when p is 2 or 3, it is a (p+1) valent linking group having 1 to 20 carbon atoms, and the linking group may contain an oxygen atom, a sulfur atom, or a nitrogen atom.

[0150] In equations (5-1) and (5-2), R 401 This may include a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a bromine atom, or an amino group, or a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, an amino group, or an ether bond, and may contain a C1-C20 hydrocarbyl group, a C1-C20 hydrocarbyloxy group, a C2-C20 hydrocarbylcarbonyl group, a C2-C20 hydrocarbyloxycarbonyl group, a C2-C20 hydrocarbylcarbonyloxy group, or a C1-C20 hydrocarbylsulfonyloxy group, or -N(R 401A )(R 401B ), -N(R 401C )-C(=O)-R 401D Or -N(R 401C )-C(=O)-OR 401D That is. R 401A and R 401B Each of these is independently a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. 401C R is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. 401DThis is an aliphatic hydrocarbyl group having 1 to 16 carbon atoms, an aryl group having 6 to 14 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may contain a halogen atom, a hydroxyl group, a saturated hydrocarbyloxy group having 1 to 6 carbon atoms, a saturated hydrocarbylcarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbylcarbonyloxy group having 2 to 6 carbon atoms. The aliphatic hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. The hydrocarbyl group, hydrocarbyloxy group, hydrocarbylcarbonyl group, hydrocarbyloxycarbonyl group, hydrocarbylcarbonyloxy group, and hydrocarbylsulfonyloxy group may be linear, branched, or cyclic. When p and / or r is 2 or more, each R 401 They may be the same or different from one another.

[0151] Of these, R 401 Examples include hydroxyl groups, -N(R 401C )-C(=O)-R 401D , -N(R 401C )-C(=O)-OR 401D Fluorine atoms, chlorine atoms, bromine atoms, methyl groups, methoxy groups, etc. are preferred.

[0152] In equations (5-1) and (5-2), Rf 1 ~Rf 4 Each of these is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is either a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 These may combine to form a carbonyl group. In particular, Rf 3 and Rf 4 It is preferable that both are fluorine atoms.

[0153] In equations (5-1) and (5-2), R 402 ~R 406Each of these is a hydrocarbyl group having 1 to 20 carbon atoms, which may independently contain a halogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. For example, in the explanation of formula (3), R 101 ~R 103 Examples of hydrocarbyl groups represented by the above are similar to those exemplified. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a hydroxyl group, carboxyl group, halogen atom, cyano group, nitro group, mercapto group, sultone ring, sulfo group, or sulfonium salt-containing group, and some of the -CH2- of the hydrocarbyl group may be substituted with an ether bond, ester bond, carbonyl group, amide bond, carbonate bond, or sulfonic acid ester bond. In addition, R 402 and R 403 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. In this case, the ring is R as described in the explanation of formula (3). 101 and R 102 Examples of rings that can be formed when these elements bond with each other, together with the sulfur atom to which they bond, are similar to those exemplified above.

[0154] Examples of cations for sulfonium salts represented by formula (5-1) are the same as those exemplified for sulfonium salts represented by formula (3). Examples of cations for iodonium salts represented by formula (5-2) are listed below, but are not limited to these. [ka]

[0155] [ka]

[0156] The anions of the onium salt represented by formula (5-1) or (5-2) include, but are not limited to, those listed below. Note that in the following formulas, X BI This is the same as above.

change

[0157]

change

[0158]

change

[0159]

change

[0160]

change

[0161]

change

[0162]

change

[0163]

change

[0164]

change

[0165]

change

[0166]

change

[0167]

change

[0168]

change

[0169]

change

[0170]

change

[0171]

change

[0172]

change

[0173]

change

[0174]

change

[0175]

change

[0176]

change

[0177] [ka]

[0178] [ka]

[0179] The content of the additive-type acid generator is preferably 0.1 to 50 parts by mass, and more preferably 1 to 40 parts by mass, per 100 parts by mass of the base polymer described later.

[0180] When the acid generator also serves as the base polymer described later, the acid generator is preferably a polymer containing repeating units derived from a compound that generates acid in response to active light or radiation. In this case, the acid generator is preferably a base polymer described later that contains repeating units f as essential units.

[0181] [Base polymer] The chemically amplified resist material of the present invention preferably includes a base polymer. In the case of a positive-type resist material, the base polymer includes repeating units containing acid-unstable groups. The repeating units containing acid-unstable groups are preferably the repeating units represented by the following formula (a1) (hereinafter also referred to as repeating unit a1) or the repeating units represented by the following formula (a2) (hereinafter also referred to as repeating unit a2). [ka]

[0182] In equations (a1) and (a2), R A Each of these is independently either a hydrogen atom or a methyl group. 11 and R 12 These are, independently, acid-unstable groups. Furthermore, if the base polymer contains both repeating unit a1 and repeating unit a2, R 11 and R 12 They may be the same or different from each other. 1This is a linking group having 1 to 12 carbon atoms, containing at least one selected from a single bond, a phenylene group or a naphthylene group, or an ester bond and a lactone ring. 2 These are single bonds or ester bonds.

[0183] Examples of monomers that give repeating unit a1 are listed below, but are not limited to these. Note that in the following formula, R A and R 11 This is the same as described above. [ka]

[0184] Examples of monomers that give repeating units a2 are listed below, but are not limited to these. Note that in the following formula, R A and R 12 This is the same as described above. [ka]

[0185] In equations (a1) and (a2), R 11 and R 12 As an acid-unstable group represented by formula (1), R 4 Examples of acid-unstable groups represented by the formula shown are similar to those exemplified above.

[0186] The base polymer may contain repeating unit b having a phenolic hydroxyl group as an adhesion group. Examples of monomers that give repeating unit b are, but are not limited to, those listed below. In the following formula, R A This is the same as described above. [ka]

[0187] The base polymer may also contain repeating units c as other adhesive groups, including hydroxyl groups other than phenolic hydroxyl groups, lactone rings, sultone rings, ether bonds, ester bonds, sulfonic acid ester bonds, carbonyl groups, sulfonyl groups, cyano groups, or carboxyl groups. Examples of monomers that give repeating units c are, but are not limited to, those listed below. In the following formula, R A This is the same as described above. [ka]

[0188] [ka]

[0189] [ka]

[0190] [ka]

[0191] [ka]

[0192] [ka]

[0193] [ka]

[0194] [ka]

[0195] The base polymer may contain repeating units d derived from indene, benzofuran, benzothiophene, acenaphthylene, chromone, coumarin, norbornadiene, or derivatives thereof. Examples of monomers that give repeating units d are, but are not limited to, those listed below. [ka]

[0196] The base polymer may contain repeating units e derived from styrene, vinylnaphthalene, vinylanthracene, vinylpyrene, methyleneindan, vinylpyridine, or vinylcarbazole.

[0197] The base polymer may contain repeating units f derived from an onium salt containing polymerizable unsaturated bonds. Preferred repeating units f include the repeating unit represented by the following formula (f1) (hereinafter also referred to as repeating unit f1), the repeating unit represented by the following formula (f2) (hereinafter also referred to as repeating unit f2), and the repeating unit represented by the following formula (f3) (hereinafter also referred to as repeating unit f3). Repeating units f1 to f3 may be used individually or in combination of two or more types. [ka]

[0198] In formulas (f1) to (f3), R A Each of these is independently either a hydrogen atom or a methyl group. 1 This refers to a single bond, an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group having 7 to 18 carbon atoms obtained by combining these, or -OZ 11 -, -C(=O)-OZ 11 -or -C(=O)-NH-Z 11 - is Z 11This is an aliphatic hydrocarbylene group, phenylene group, naphthylene group having 1 to 6 carbon atoms, or a group having 7 to 18 carbon atoms obtained by combining these, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. 2 This is a single bond, -Z 21 -C(=O)-O-, -Z 21 -O- or -Z 21 -OC(=O)- Z 21 This is a saturated hydrocarbylene group having 1 to 12 carbon atoms, and may contain a carbonyl group, an ester bond, or an ether bond. 3 This includes single bonds, methylene groups, ethylene groups, phenylene groups, fluorinated phenylene groups, phenylene groups substituted with trifluoromethyl groups, -OZ 31 -, -C(=O)-OZ 31 -or -C(=O)-NH-Z 31 - is Z 31 This is a phenylene group substituted with an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a trifluoromethyl group, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. 11 and Z 31 The aliphatic hydrocarbylene group represented by can be saturated or unsaturated, and can be linear, branched, or cyclic. 21 The saturated hydrocarbylene group represented by can be linear, branched, or cyclic.

[0199] In formulas (f1) to (f3), R 21 ~R 28 Each of these is a hydrocarbyl group having 1 to 20 carbon atoms, which may independently contain a halogen atom or a heteroatom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3). 101 ~R 103Examples similar to those exemplified in the description can be given. Furthermore, some or all of the hydrogen atoms of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and some of the -CH2- of the hydrocarbyl group may be substituted with a group containing heteroatoms such as oxygen, sulfur, or nitrogen atoms, and as a result, it may contain a hydroxyl group, fluorine atom, chlorine atom, bromine atom, iodine atom, cyano group, nitro group, mercapto group, carbonyl group, ether bond, ester bond, sulfonic acid ester bond, carbonate bond, lactone ring, sultone ring, carboxylic acid anhydride (-C(=O)-OC(=O)-), haloalkyl group, etc.

[0200] Also, R 23 and R 24 or R 26 and R 27 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. In this case, the ring is defined as R in the explanation of formula (3). 101 and R 102 Examples of rings that can be formed when these elements combine with the sulfur atom to which they are bonded are similar to those exemplified.

[0201] In formula (f2), R HF This is either a hydrogen atom or a trifluoromethyl group.

[0202] In formula (f1), M -This is a non-nucleophilic counterion. Examples of the aforementioned non-nucleophilic counterions include halide ions such as chloride ions and bromide ions; fluoroalkyl sulfonate ions such as triflate ions, 1,1,1-trifluoroethanesulfonate ions, and nonafluorobutanesulfonate ions; aryl sulfonate ions such as tosylate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, and 1,2,3,4,5-pentafluorobenzenesulfonate ions; alkyl sulfonate ions such as mesylate ions and butanesulfonate ions; imide ions such as bis(trifluoromethylsulfonyl)imide ions, bis(perfluoroethylsulfonyl)imide ions, and bis(perfluorobutylsulfonyl)imide ions; and methide ions such as tris(trifluoromethylsulfonyl)methide ions and tris(perfluoroethylsulfonyl)methide ions.

[0203] Other examples of the aforementioned non-nucleophilic counterions include a sulfonate ion in which the α-position is substituted with a fluorine atom, represented by the following formula (f1-1); a sulfonate ion in which the α-position is substituted with a fluorine atom and the β-position is substituted with a trifluoromethyl group, represented by the following formula (f1-2); and a sulfonate ion containing an iodine atom, represented by the aforementioned formula (5-1). [ka]

[0204] In formula (f1-1), R 31 R is a hydrogen atom or a hydrocarbyl group having 1 to 20 carbon atoms, and the hydrocarbyl group may contain an ether bond, an ester bond, a carbonyl group, a lactone ring, or a fluorine atom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3A'). 111 Examples of hydrocarbyl groups represented by the same formula as those exemplified above include those shown.

[0205] In formula (f1-2), R 32R is a hydrogen atom, a hydrocarbyl group having 1 to 30 carbon atoms, or a hydrocarbylcarbonyl group having 2 to 30 carbon atoms, and the hydrocarbyl group and hydrocarbylcarbonyl group may contain an ether bond, an ester bond, a carbonyl group, or a lactone ring. The hydrocarbyl portion of the hydrocarbyl group and hydrocarbylcarbonyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. A specific example is R in formula (3A'). 111 Examples of hydrocarbyl groups represented by the same formula as those exemplified above include those shown.

[0206] Examples of monomer cations that give the repeating unit f1 are listed below, but are not limited to these. Note that in the following formula, R A This is the same as described above. [ka]

[0207] Examples of monomer cations that give repeating units f2 or f3 include those similar to those exemplified as cations of sulfonium salts represented by formula (3).

[0208] Examples of monomer anions that give the repeating unit f2 are listed below, but are not limited to these. Note that in the following formula, R A This is the same as described above. [ka]

[0209] [ka]

[0210] Examples of monomer anions that give the repeating unit f3 are listed below, but are not limited to these. Note that in the following formula, R A This is the same as described above. [ka]

[0211] [Chemical formula]

[0212] By bonding an acid generator to the polymer main chain, acid diffusion can be reduced, and a decrease in resolution due to blurring of acid diffusion can be prevented. In addition, by uniformly dispersing the acid generator, LWR and CDU are improved.

[0213] When including the repeating unit f, the base polymer also functions as the above-described acid generator. In this case, since the base polymer is integrated with the acid generator (that is, it is a polymer-bound type acid generator), the chemically amplified resist material of the present invention may or may not contain an additive acid generator.

[0214] The base polymer for a chemically amplified positive resist material essentially requires a repeating unit a1 or a2 containing an acid-labile group. In this case, the content ratios of the repeating units a1, a2, b, c, d, e, and f are preferably 0 ≦ a1 < 1.0, 0 ≦ a2 < 1.0, 0 < a1 + a2 < 1.0, 0 ≦ b ≦ 0.9, 0 ≦ c ≦ 0.9, 0 ≦ d ≦ 0.8, 0 ≦ e ≦ 0.8, and 0 ≦ f ≦ 0.5, more preferably 0 ≦ a1 ≦ 0.9, 0 ≦ a2 ≦ 0.9, 0.1 ≦ a1 + a2 ≦ 0.9, 0 ≦ b ≦ 0.8, 0 ≦ c ≦ 0.8, 0 ≦ d ≦ 0.7, 0 ≦ e ≦ 0.7, and 0 ≦ f ≦ 0.4, and still more preferably 0 ≦ a1 ≦ 0.8, 0 ≦ a2 ≦ 0.8, 0.1 ≦ a1 + a2 ≦ 0.8, 0 ≦ b ≦ 0.75, 0 ≦ c ≦ 0.75, 0 ≦ d ≦ 0.6, 0 ≦ e ≦ 0.6, and 0 ≦ f ≦ 0.3. When the base polymer is a polymer-bound type acid generator, the content ratio of the repeating unit f is preferably 0 < f ≦ 0.5, more preferably 0.01 ≦ f ≦ 0.4, and still more preferably 0.02 ≦ f ≦ 0.3. When the repeating unit f is at least one selected from the repeating units f1 to f3, f = f1 + f2 + f3. Also, a1 + a2 + b + c + d + e + f = 1.0.

[0215] On the one hand, for the base polymer used in the chemically amplified negative resist material, an acid-labile group is not necessarily required. Examples of such base polymers include those containing repeating unit b and optionally further containing repeating units c, d, e, and / or f. The content ratios of these repeating units are preferably 0 < b ≤ 1.0, 0 ≤ c ≤ 0.9, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, and 0 ≤ f ≤ 0.5, more preferably 0.2 ≤ b ≤ 1.0, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.7, and 0 ≤ f ≤ 0.4, and even more preferably 0.3 ≤ b ≤ 1.0, 0 ≤ c ≤ 0.75, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 0.6, and 0 ≤ f ≤ 0.3. When the base polymer is a polymer-bound acid generator, the content ratio of repeating unit f is preferably 0 < f ≤ 0.5, more preferably 0.01 ≤ f ≤ 0.4, and even more preferably 0.02 ≤ f ≤ 0.3. When repeating unit f is at least one selected from repeating units f1 to f3, f = f1 + f2 + f3. Also, b + c + d + e + f = 1.0.

[0216] To synthesize the base polymer, for example, monomers that give the aforementioned repeating units may be heated in an organic solvent with a radical polymerization initiator added to perform polymerization.

[0217] Examples of the organic solvent used during polymerization include toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, etc. Examples of the polymerization initiator include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2-azobis(2-methylpropionate), benzoyl peroxide, lauroyl peroxide, etc. The temperature during polymerization is preferably 50 to 80°C. The reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours.

[0218] When copolymerizing monomers containing hydroxyl groups, the hydroxyl groups may be substituted with acetal groups that are easily deprotected by acids such as ethoxyethoxy groups during polymerization, and then deprotected with a weak acid and water after polymerization. Alternatively, they may be substituted with acetyl groups, formyl groups, pivaloyl groups, etc., and then subjected to alkaline hydrolysis after polymerization.

[0219] When copolymerizing hydroxystyrene or hydroxyvinylnaphthalene, acetoxystyrene or acetoxyvinylnaphthalene may be used instead of hydroxystyrene or hydroxyvinylnaphthalene, and the acetoxy group may be deprotected by alkaline hydrolysis after polymerization to obtain hydroxystyrene or hydroxyvinylnaphthalene.

[0220] Ammonia water, triethylamine, etc., can be used as the base during alkaline hydrolysis. The reaction temperature is preferably -20 to 100°C, more preferably 0 to 60°C. The reaction time is preferably 0.2 to 100 hours, more preferably 0.5 to 20 hours.

[0221] The base polymer has a polystyrene-based weight-average molecular weight (Mw) of 1,000 to 500,000, more preferably 2,000 to 30,000, determined by gel permeation chromatography (GPC) using THF as a solvent. When Mw is within this range, the heat resistance and solubility in alkaline developers of the resist film are good.

[0222] Furthermore, if the molecular weight distribution (Mw / Mn) of the base polymer is broad, low molecular weight and high molecular weight polymers may be present, which may result in the appearance of foreign matter on the pattern or deterioration of the pattern shape after exposure. As the pattern rules become finer, the influence of Mw and Mw / Mn tends to increase. Therefore, in order to obtain a resist material suitable for fine pattern dimensions, it is preferable that the Mw / Mn of the base polymer be narrowly dispersed, between 1.0 and 2.0, and particularly between 1.0 and 1.5.

[0223] The base polymer may contain two or more polymers with different composition ratios, Mw, and Mw / Mn.

[0224] [Organic solvents] The chemically amplified resist material of the present invention may contain an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the components described above and the components described later. Examples of the organic solvent include ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone, as described in paragraphs

[0144] to

[0145] of Japanese Patent Application Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, and ethylene glycol Examples include ethers such as monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, 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; and lactones such as γ-butyrolactone.

[0225] In the chemically amplified resist material of the present invention, the content of the organic solvent is preferably 100 to 10,000 parts by mass, and more preferably 200 to 8,000 parts by mass, per 100 parts by mass of the base polymer. The organic solvent may be used alone or as a mixture of two or more types.

[0226] [Other ingredients] In addition to the components described above, the chemically amplified resist material of the present invention may also contain surfactants, dissolution inhibitors, crosslinking agents, water-repellency enhancers, acetylene alcohols, and the like.

[0227] Examples of the surfactants mentioned above include those described in paragraphs

[0165] to

[0166] of Japanese Patent Publication No. 2008-111103. By adding a surfactant, the coatability of the resist material can be further improved or controlled. When the chemically amplified resist material of the present invention contains the surfactant, its content is preferably 0.0001 to 10 parts by mass per 100 parts by mass of the base polymer. The surfactant may be used alone or in combination of two or more types.

[0228] When the chemical amplification resist material of the present invention is of the positive type, the difference in dissolution rate between the exposed and unexposed areas can be further increased by incorporating a dissolution inhibitor, thereby further improving the resolution. Examples of the dissolution inhibitor include compounds in which the hydrogen atoms of the phenolic hydroxyl groups of a compound having a molecular weight of preferably 100 to 1,000, more preferably 150 to 800, and containing two or more phenolic hydroxyl groups in the molecule are substituted with acid-unstable groups in a total proportion of 0 to 100 mol%, or compounds in which the hydrogen atoms of the carboxyl groups of a compound containing a carboxyl group in the molecule are substituted with acid-unstable groups in an average total proportion of 50 to 100 mol%. Specifically, examples include compounds in which the hydrogen atoms of the hydroxyl group or carboxyl group of bisphenol A, trisphenol, phenolphthalein, cresol novolac, naphthalenecarboxylic acid, adamantanecarboxylic acid, and cholic acid are substituted with acid-unstable groups, as described in paragraphs

[0155] to

[0178] of Japanese Patent Application Publication No. 2008-122932.

[0229] When the chemically amplified resist material of the present invention is of the positive type and contains the dissolution inhibitor, the content thereof is preferably 0 to 50 parts by mass, and more preferably 5 to 40 parts by mass, per 100 parts by mass of the base polymer. The dissolution inhibitor may be used alone or in combination of two or more types.

[0230] On the other hand, if the chemically amplified resist material of the present invention is negative type, a negative type pattern can be obtained by adding a crosslinking agent to reduce the dissolution rate of the exposed area. Examples of the crosslinking agent include epoxy compounds, melamine compounds, guanamine compounds, glycoluryl compounds or urea compounds, isocyanate compounds, azide compounds, and compounds containing double bonds such as alkenyloxy groups, which are substituted with at least one group selected from methylol groups, alkoxymethyl groups, and acyloxymethyl groups. These may be used as additives or introduced as pendant groups in the polymer side chains. Compounds containing hydroxyl groups can also be used as crosslinking agents.

[0231] Examples of the epoxy compound include tris(2,3-epoxypropyl) isocyanurate, trimethylolmethane triglycidyl ether, trimethylolpropane triglycidyl ether, and triethylolethane triglycidyl ether.

[0232] Examples of the melamine compounds include hexamethylmelamine, hexamethoxymethylmelamine, compounds in which 1 to 6 methylol groups of hexamethylmelamine are methoxymethylated or mixtures thereof, hexamethoxyethylmelamine, hexaacyloxymethylmelamine, compounds in which 1 to 6 methylol groups of hexamethylmelamine are acyloxymethylated or mixtures thereof.

[0233] Examples of the guanamine compounds include tetramethylolguanamine, tetramethoxymethylguanamine, compounds in which 1 to 4 methylol groups of tetramethylolguanamine are methoxymethylated or mixtures thereof, tetramethoxyethylguanamine, tetraacyloxyguanamine, compounds in which 1 to 4 methylol groups of tetramethylolguanamine are acyloxymethylated or mixtures thereof.

[0234] Examples of glycoluryl compounds include tetramethylol glycoluryl, tetramethoxy glycoluryl, tetramethoxymethyl glycoluryl, compounds in which 1 to 4 methylol groups of tetramethylol glycoluryl are methoxymethylated or mixtures thereof, compounds in which 1 to 4 methylol groups of tetramethylol glycoluryl are acyloxymethylated or mixtures thereof. Examples of urea compounds include tetramethylolurea, tetramethoxymethylurea, compounds in which 1 to 4 methylol groups of tetramethylolurea are methoxymethylated or mixtures thereof, tetramethoxyethylurea, and the like.

[0235] Examples of the isocyanate compounds include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and cyclohexane diisocyanate.

[0236] Examples of the aforementioned azide compounds include 1,1'-biphenyl-4,4'-bisazide, 4,4'-methylidenebisazide, and 4,4'-oxybisazide.

[0237] Examples of compounds containing the aforementioned alkenyloxy group include ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, 1,4-butanediol divinyl ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylolpropane trivinyl ether, hexanediol divinyl ether, 1,4-cyclohexanediol divinyl ether, pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, and trimethylolpropane trivinyl ether.

[0238] When the chemically amplified resist material of the present invention is of the negative type and contains the crosslinking agent, the content of the crosslinking agent is preferably 0.1 to 50 parts by mass, and more preferably 1 to 40 parts by mass, per 100 parts by mass of the base polymer. The crosslinking agent may be used alone or in combination of two or more types.

[0239] The water-repellent enhancer improves the water repellency of the resist film surface and can be used in immersion lithography without a topcoat. Preferred water-repellent enhancers include polymers containing alkyl fluoride, polymers containing 1,1,1,3,3,3-hexafluoro-2-propanol residues of a specific structure, and those exemplified in Japanese Patent Publication No. 2007-297590 and Japanese Patent Publication No. 2008-111103 are more preferred. The water-repellent enhancer needs to be soluble in an alkaline developer or an organic solvent developer. The aforementioned water-repellent enhancer having a specific 1,1,1,3,3,3-hexafluoro-2-propanol residue exhibits good solubility in the developer. As a water-repellent enhancer, polymers containing repeating units including amino groups or amine salts are highly effective in preventing acid evaporation during post-exposure baking (PEB) and thus preventing poor hole pattern opening after development. When the chemically amplified resist material of the present invention contains the water-repellency improving agent, its content is preferably 0 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the base polymer. The water-repellency improving agent may be used alone or in combination of two or more types.

[0240] Examples of the acetylene alcohols include those described in paragraphs

[0179] to

[0182] of Japanese Patent Publication No. 2008-122932. When the chemical amplification resist material of the present invention contains the acetylene alcohols, the content is preferably 0 to 5 parts by mass per 100 parts by mass of the base polymer. The acetylene alcohols may be used individually or in combination of two or more types.

[0241] [Pattern formation method] When the chemically amplified resist material of the present invention is used in the manufacture of various integrated circuits, known lithography techniques can be applied. For example, a pattern formation method may include a step of forming a resist film on a substrate using the chemically amplified resist material described above, a step of exposing the resist film with high-energy rays, and a step of developing the exposed resist film using a developer.

[0242] First, the chemically amplified resist material of the present invention is applied to 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.) by a suitable coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, or doctor coating, so that the coating film thickness is 0.1 to 2 μm. This is then pre-baked on a hot plate, preferably at 60 to 150°C for 10 seconds to 30 minutes, more preferably at 80 to 120°C for 30 seconds to 20 minutes, to form a resist film.

[0243] Next, the resist film is exposed using high-energy rays. Examples of high-energy rays include ultraviolet rays, far-ultraviolet rays, EB rays, EUV rays with wavelengths of 3 to 15 nm, X-rays, soft X-rays, excimer laser light, gamma rays, and synchrotron radiation. When using ultraviolet rays, far-ultraviolet rays, EUV rays, X-rays, soft X-rays, excimer laser light, gamma rays, or synchrotron radiation as the high-energy rays, the exposure amount is preferably 1 to 200 mJ / cm², either directly or using a mask to form the desired pattern. 2 To the extent, more preferably 10 to 100 mJ / cm² 2 Irradiate to the extent of [a certain degree]. When using EB as the high-energy beam, the exposure dose is preferably 0.1 to 100 μC / cm². 2 To a degree, more preferably 0.5 to 50 μC / cm² 2The pattern is drawn either directly or using a mask to form the desired pattern. The chemically amplified resist material of the present invention is particularly suitable for fine patterning using high-energy rays, including i-rays with a wavelength of 365 nm, KrF excimer laser light, ArF excimer laser light, EB, EUV, X-rays, soft X-rays, gamma rays, and synchrotron radiation.

[0244] In addition to conventional exposure methods, immersion methods can also be used, in which a liquid with a refractive index of 1.0 or higher, such as water, is interposed between the resist film and the projection lens. In this case, a protective film insoluble in water can also be used.

[0245] After exposure, PEB may be performed on a hot plate or in an oven, preferably at 60-150°C for 10 seconds to 30 minutes, more preferably at 80-120°C for 30 seconds to 20 minutes.

[0246] After exposure or PEB, the exposed resist film is developed using a developer solution containing 0.1 to 10% by mass, preferably 2 to 5% by mass, of an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, or tetrabutylammonium hydroxide, for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, by conventional methods such as the dip method, puddle method, or spray method, thereby forming the desired pattern. In the case of positive-type resist materials, the areas irradiated with light dissolve in the developer solution, while the unexposed areas do not dissolve, forming the desired positive-type pattern on the substrate. In the case of negative-type resist materials, the opposite is true: the areas irradiated with light become insoluble in the developer solution, while the unexposed areas dissolve.

[0247] Negative patterns can also be obtained by developing with organic solvents using positive-type resist materials containing a base polymer with acid-unstable groups. The developers used in this process include 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methylacetophenone, propyl acetate, butyl acetate, isobutyl acetate, pentyl acetate, butenyl acetate, isopentyl acetate, propyl formate, butyl formate, isobutyl formate, pentyl formate, isopentyl formate, methyl valerate, methyl pentenoate, methyl crotate, ethyl crotate, Examples include methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, pentyl lactate, isopentyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenyl acetate, and 2-phenylethyl acetate. These organic solvents may be used individually or in mixtures of two or more.

[0248] At the end of development, rinsing is performed. The rinsing solution should preferably be a solvent that mixes with the developer but does not dissolve the resist film. Suitable solvents include C3-C10 alcohols, C8-C12 ether compounds, C6-C12 alkanes, alkenes, alkynes, and aromatic solvents.

[0249] The C3-C10 alcohols include n-propyl alcohol, isopropyl alcohol, 1-butyl alcohol, 2-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, tert-pentyl alcohol, neopentyl alcohol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methyl-3-pentanol, cyclopentanol, 1-hexanol, 2-hexanol, 3-hexanol, Examples include 2,3-dimethyl-2-butanol, 3,3-dimethyl-1-butanol, 3,3-dimethyl-2-butanol, 2-ethyl-1-butanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, 4-methyl-3-pentanol, cyclohexanol, and 1-octanol.

[0250] Examples of the ether compounds having 8 to 12 carbon atoms include di-n-butyl ether, diisobutyl ether, di-sec-butyl ether, di-n-pentyl ether, diisopentyl ether, di-sec-pentyl ether, di-tert-pentyl ether, and di-n-hexyl ether.

[0251] Examples of C6-C12 alkanes include hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, and cyclononane. Examples of C6-C12 alkenes include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, and cyclooctene. Examples of C6-C12 alkynes include hexine, heptine, and octine.

[0252] Examples of the aforementioned aromatic solvents include toluene, xylene, ethylbenzene, isopropylbenzene, tert-butylbenzene, and mesitylene.

[0253] Rinsing can reduce the occurrence of resist pattern deformation and defects. However, rinsing is not always necessary, and omitting it can reduce the amount of solvent used.

[0254] The developed hole patterns and trench patterns can also be shrunk using thermal flow, RELACS, or DSA techniques. A shrinking agent is applied to the hole pattern, and crosslinking of the shrinking agent occurs on the surface of the resist film due to the diffusion of an acid catalyst from the resist film during baking, causing the shrinking agent to adhere to the side walls of the hole pattern. The baking temperature is preferably 70 to 180°C, more preferably 80 to 170°C, and the baking time is preferably 10 to 300 seconds, during which excess shrinking agent is removed and the hole pattern is reduced in size. [Examples]

[0255] The present invention will be specifically described below with reference to synthesis examples, examples, and comparative examples, but the present invention is not limited to the following examples.

[0256] The structures of the quenchers Q-1 to Q-28 used in the chemically amplified resist material are shown below. [ka]

[0257] [ka]

[0258] [ka]

[0259] [ka]

[0260] [ka]

[0261] [Synthesis Example] Synthesis of base polymers (P-1 to P-3) Each monomer was combined and copolymerized in THF, a solvent. The reaction solution was added to methanol, and the precipitated solid was washed with hexane, then isolated and dried to obtain base polymers (P-1 to P-3) with the following compositions. The compositions of the obtained base polymers are: 1 Mw and Mw / Mn were confirmed by H-NMR using GPC (solvent: THF, standard: polystyrene). [ka]

[0262] [Examples 1-30, Comparative Examples 1-3] Preparation and Evaluation of Chemically Amplified Resist Materials (1) Preparation of chemically amplified resist materials Chemically amplified resist materials were prepared by dissolving each component in the compositions shown in Tables 1-3 and filtering the solutions through a 0.2 μm filter.

[0263] In Tables 1-3, the components are as follows: • Organic solvent: PGMEA (propylene glycol monomethyl ether acetate) DAA (Diacetone Alcohol) EL (DL-ethyl lactate)

[0264] • Acid generators: PAG-1~PAG-3 [ka]

[0265] • Comparative Quenchers: cQ-1~cQ-3 [ka]

[0266] • Blend Quencher: bQ-1~bQ-4 [ka]

[0267] (2) EUV lithography evaluation Each resist material shown in Tables 1-3 was spin-coated onto a Si substrate on which a silicon-containing spin-on hard mask SHB-A940 (silicon content 43 mass%) manufactured by Shin-Etsu Chemical Co., Ltd. had been formed to a thickness of 20 nm. A resist film with a thickness of 50 nm was fabricated by pre-baking at 100°C for 60 seconds using a hot plate. The resist film was exposed using an ASML EUV scanner NXE3400 (NA 0.33, σ 0.9 / 0.6, quadruple pole illumination, wafer-mounted dimensions of 44 nm pitch, +20% bias hole pattern mask), and PEB was performed on a hot plate at the temperatures listed in Tables 1-3 for 60 seconds. Development was then performed with a 2.38 mass% TMAH aqueous solution for 30 seconds to form a hole pattern with dimensions of 22 nm. Using a Hitachi High-Technologies Corporation length-measuring SEM (CG6300), the exposure amount at which a hole dimension of 22 nm was formed was measured and defined as the sensitivity. The dimensions of 50 holes at this point were also measured, and the CDU was defined as three times the standard deviation (σ) calculated from these results (3σ). The results are shown in Tables 1-3.

[0268] [Table 1]

[0269] [Table 2]

[0270] [Table 3]

[0271] The results shown in Tables 1-3 indicate that the chemically amplified resist material of the present invention, which contains a compound having an aromatic group substituted with a nitro group, a heterocyclic amine structure, and a carboxyl group substituted with an acid-unstable group in its molecule, exhibits superior CDU.

Claims

1. A chemically amplified resist material comprising a quencher and an acid generator, wherein the quencher is a compound represented by the following formula (2). 【Chemistry 1】 (In the formula, m is 1 or 2, n1 is 1 or 2, and n2 is an integer between 0 and 3, where 1 ≤ n1 + n2 ≤ 4.) Circle R' is a heterocycle with 3 to 12 carbon atoms containing a nitrogen atom in the formula, and includes ether bonds, ester bonds, sulfide bonds, sulfonyl groups, -N= and -N(R 1 ) - may include at least one selected from the above. L is an ether bond, ester bond, amide bond, or thioester bond. X 1 This is a single bond or a linear saturated hydrocarbylene group having 1 to 3 carbon atoms. X 2 It is a single bond. R 1 These are a hydrogen atom, a saturated hydrocarbyl group having 1 to 6 carbon atoms, an acetyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an n-propyloxycarbonyl group, an isopropyloxycarbonyl group, a tert-butoxycarbonyl group, a tert-pentyloxycarbonyl group, a methylcyclopentyloxycarbonyl group, an ethylcyclopentyloxycarbonyl group, a propylcyclopentyloxycarbonyl group, a phenyl group, a benzyl group, a naphthyl group, a naphthylmethyl group, a methylcyclohexyloxycarbonyl group, an ethylcyclohexyloxycarbonyl group, a 9-fluorenylmethyloxycarbonyl group, an allyloxycarbonyl group, a methoxymethyl group, an ethoxymethyl group, a propoxymethyl group, or a butoxymethyl group. R 2 This is a hydrogen atom, a halogen atom, a saturated hydrocarbyl group having 1 to 6 carbon atoms, or a phenyl group, and some or all of the hydrogen atoms of the saturated hydrocarbyl group or phenyl group may be substituted with halogen atoms. R 3 This is a hydrogen atom, a halogen atom, or a hydrocarbyl group having 1 to 10 carbon atoms. R 4 It is an acid-unstable group.

2. The chemically amplified resist material according to claim 1, wherein the acid generating agent generates sulfonic acid, imido acid, or methido acid.

3. Furthermore, the chemically amplified resist material according to claim 1, further comprising a base polymer.

4. The chemically amplified resist material according to claim 3, wherein the base polymer comprises a repeating unit represented by the following formula (a1) or a repeating unit represented by the following formula (a2). 【Chemistry 2】 (In the formula, R A Each of these is independently either a hydrogen atom or a methyl group. R 11 and R 12 are each independently an acid-labile group. Y 1 This is a linking group having 1 to 12 carbon atoms, containing at least one selected from a single bond, a phenylene group or a naphthylene group, or an ester bond and a lactone ring. Y 2 (These are single bonds or ester bonds.)

5. The chemically amplified resist material according to claim 4, which is a chemically amplified positive resist material.

6. The chemically amplified resist material according to claim 3, wherein the base polymer does not contain acid-unstable groups.

7. The chemically amplified resist material according to claim 6, which is a chemically amplified negative resist material.

8. The chemically amplified resist material according to claim 4, wherein the base polymer contains repeating units represented by any of the following formulas (f1) to (f3). 【Transformation 3】 (In the formula, R A Each of these is independently either a hydrogen atom or a methyl group. Z 1 This includes single bonds, aliphatic hydrocarbylene groups having 1 to 6 carbon atoms, phenylene groups, naphthylene groups, or groups having 7 to 18 carbon atoms obtained by combining these, or -O-Z. 11 -, -C(=O)-O-Z 11 - or -C(=O)-NH-Z 11 - is Z 11 This is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group having 7 to 18 carbon atoms obtained by combining these, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. Z 2 This is a single bond, -Z 21 -C(=O)-O-, -Z 21 -O- or -Z 21 -O-C(=O)-. Z 21 This is a saturated hydrocarbylene group having 1 to 12 carbon atoms, and may contain a carbonyl group, an ester bond, or an ether bond. Z 3 This includes single bonds, methylene groups, ethylene groups, phenylene groups, fluorinated phenylene groups, trifluoromethyl groups, and -O-Z. 31 -, -C(=O)-O-Z 31 - or -C(=O)-NH-Z 31 - is Z 31 This is a phenylene group substituted with an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a trifluoromethyl group, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. R 21 ~R 28 Each of these is independently a C1-C20 hydrocarbyl group which may contain a halogen atom or a heteroatom. 23 and R 24 or R 26 and R 27 However, they may bond with each other to form a ring with the sulfur atom to which they are bonded. R HF This is either a hydrogen atom or a trifluoromethyl group. M - (It is a non-nucleophilic counterion.)

9. Furthermore, the chemically amplified resist material according to claim 1, further comprising an organic solvent.

10. Furthermore, the chemically amplified resist material according to claim 1, further comprising a surfactant.

11. A pattern forming method comprising the steps of: forming a resist film on a substrate using a chemically amplified resist material according to any one of claims 1 to 10; exposing the resist film with a high-energy beam; and developing the exposed resist film using a developer.

12. The pattern forming method according to claim 11, wherein the high-energy ray is an i-ray with a wavelength of 365 nm, ArF excimer laser light with a wavelength of 193 nm, KrF excimer laser light with a wavelength of 248 nm, an electron beam, or extreme ultraviolet light with a wavelength of 3 to 15 nm.

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