Resist material and pattern forming method

Abstract

To provide a resist material which has 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 resist material contains a bis-onium salt containing: a divalent anion which has a phenoxide anion structure substituted with an iodine atom and a fluorosulfonic acid anion structure bonded to an aromatic ring of the phenoxide anion structure; and an onium cation.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resist material and a patterning method.

Background Art

[0002] With the increasing integration density and speed of LSIs, the miniaturization of pattern rules has been rapidly progressing. This is because the high-speed communication of 5G and the spread of artificial intelligence (AI) are advancing, and high-performance devices for processing them are required. As the most advanced miniaturization technology, mass production of 5nm node and 3nm node devices by extreme ultraviolet (EUV) lithography with a wavelength of 13.5nm is being carried out. Furthermore, studies using EUV lithography are also underway for next-generation 2nm node devices and successive-generation 14Å nodes, and IMEC in Belgium has announced the development of 2Å devices.

[0003] With the progress of miniaturization, image blur due to acid diffusion has become a problem. In order to ensure the resolution of fine patterns with a processing dimension of 45nm or less, it has been proposed that not only the improvement of the dissolution contrast conventionally proposed but also the control of acid diffusion is important (Non-Patent Document 1). However, since the chemically amplified resist material increases the sensitivity and contrast by acid diffusion, if the post-exposure bake (PEB) temperature is lowered or the time is shortened to suppress acid diffusion to the limit, the sensitivity and contrast will be significantly reduced.

[0004] In EUV resist materials, it is necessary to simultaneously achieve high sensitivity, high resolution, and low line width roughness (LWR). Shortening the acid diffusion distance improves LWR and dimensional uniformity (CDU), but reduces the sensitivity. For example, lowering the PEB temperature improves LWR and CDU, but reduces the sensitivity. Increasing the amount of quencher added also improves LWR and CDU, but reduces the sensitivity. It is necessary to break the trade-off relationship between sensitivity and LWR.

[0005] Onium salts containing anions having iodine atoms or bromine atoms have been proposed as acid generators to be added to resist materials (Patent Documents 1 to 4). By having iodine atoms with high EUV absorption or bromine atoms with high ionization efficiency, the efficiency of decomposition of the acid generator during exposure is increased, resulting in higher sensitivity. The amount of photon absorption increases, and the physical contrast can be enhanced.

[0006] Since EUV light with a wavelength of 13.5 nm has a wavelength shorter by more than one order of magnitude compared to ArF excimer laser light with a wavelength of 193 nm, it has high energy and is greatly affected by the variation in the number of photons (Non-Patent Document 2). It has been pointed out that this causes deterioration of LWR (Non-Patent Document 3). In addition, with the progress of miniaturization, the influence of LWR deterioration due to variations (Resist, Stochastics) in resist components (polymers, PAGs, quenchers) has also been pointed out (Non-Patent Document 4).

[0007] Resist materials containing a polymer in which an acid generator (PAG) and a quencher (PDQ) are bonded have been proposed (Patent Document 5). By integrating the polymer, PAG, and quencher, the variations in their presence are suppressed, and LWR and CDU are improved. Furthermore, resist materials containing an additive in which PAG and a quencher are bonded have also been proposed (Patent Documents 6 and 7).

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

[0009] [Non-Patent Document 1] SPIE Vol. 6520 65203L-1 (2007) [Non-Patent Document 2] SPIE Vol. 3331 535 (1998) [Non-Patent Document 3] SPIE Vol. 7273 727343-1 (2009) [Non-Patent Document 4] SPIE Vol. 9776 97760V-1 (2016) [Summary of the Invention] [Problems to be Solved by the Invention]

[0010] There is a demand for the development of a resist material that is more sensitive than conventional resist materials and can improve the LWR of line patterns and the CDU of hole patterns.

[0011] In view of the above circumstances, the present invention aims to provide a resist material that is highly sensitive and has improved LWR and CDU, whether it is a positive type or a negative type, and a pattern formation method using the same. [Means for Solving the Problems]

[0012] As a result of intensive studies to achieve the above object, the present inventors have found that by using a bisonium salt containing a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonic acid anion structure bonded to the aromatic ring of the phenoxide anion structure and an onium cation as an acid generator and a quencher, the acid generator is directly excited by radiation exposure, and the influence of the diffusion of secondary electrons is eliminated. As a result, a resist material having high sensitivity, improved LWR and CDU, high contrast, excellent resolution, and a wide process margin can be obtained, and the present invention has been completed.

[0013] That is, the present invention provides the following resist materials and pattern forming methods. 1. A resist material containing a bisonium salt containing a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonic acid anion structure bonded to the aromatic ring of the phenoxide anion structure and an onium cation. 2. The resist material of 1, wherein the bisonium salt is represented by the following formula (1). [Chemical formula] (In the formula, m is an integer of 1 to 4. n is an integer of 0 to 3. However, 1 ≦ m + n ≦ 4. p is 0 or 1. X 1 and X 2 are each independently a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond or a carbamate bond. R 1 is a hydrocarbyl group having 1 to 10 carbon atoms, a halogen atom other than an iodine atom, a nitro group or a cyano group, and the hydrocarbyl group may have at least one selected from a halogen atom, an oxygen atom, a sulfur atom and a nitrogen atom. R 2 is a single bond or a hydrocarbylene group having 1 to 40 carbon atoms, and the hydrocarbylene group may contain at least one selected from an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom. Rf1 ~Rf 4 is, independently of one another, a hydrogen atom, a fluorine atom or a trifluoromethyl group, provided that when p is 0, at least one of Rf 3 and Rf 4 is a fluorine atom or a trifluoromethyl group, and when p is 1, at least one of Rf 1 ~Rf 4 is a fluorine atom or a trifluoromethyl group. Further, Rf 1 and Rf 2 may combine to form a carbonyl group. M + is a sulfonium cation or an iodonium cation.) 3. Further, a resist material comprising a base polymer according to 1 or 2. 4. The resist material according to 3, wherein the base polymer contains a repeating unit represented by the following formula (a1) or (a2).

Chemical formula

Advantages of the Invention

[0014] A resist film containing a bis-onium salt comprising a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonic acid anion structure bonded to the aromatic ring of the phenoxide anion structure, and an onium cation is directly excited during exposure due to its large absorption of EUV light and has the characteristic of suppressing acid diffusion. This can prevent a decrease in resolution due to secondary electrons and blurring of acid diffusion. The bis-onium salt is in a form in which an acid generator of an onium salt that generates sulfonic acid and a quencher of an onium salt that generates iodinated phenol are bonded, and the acid generator and the quencher are always arranged at a constant distance. Therefore, by improving the aforementioned Resist Stochastics, it becomes possible to improve LWR and CDU. By having an iodine atom on the quencher side, the absorption on the quencher side is higher than that on the acid generator side, and the decomposition efficiency on the quencher side is higher. This makes it possible to construct a resist material with high sensitivity and improved LWR and CDU.

Embodiments for Carrying Out the Invention

[0015] [Resist Material] The resist material of the present invention contains a bis-onium salt comprising a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonic acid anion structure bonded to the aromatic ring of the phenoxide anion structure, and an onium cation. The bis-onium salt is an acid generator-cum-quencher having the functions of both an acid generator and a quencher. Due to the light absorption by the iodine atom, the high reactivity of fluorosulfonic acid, and the acid diffusion controllability due to the presence of a quencher in the vicinity at all times, the acid diffusion is small and the diffusion distance is uniform. This can improve LWR and CDU.

[0016] The effect of improving LWR and CDU by the bis-onium salt used in the present invention is effective in both positive pattern formation and negative pattern formation by alkali aqueous solution development, and in negative pattern formation in organic solvent development.

[0017] [Bis-oxonium salt] As the bis-oxonium salt, those represented by the following formula (1) are preferable. [Chemical formula]

[0018] In formula (1), m is an integer from 1 to 4. n is an integer from 0 to 3. However, 1 ≤ m + n ≤ 4. p is 0 or 1.

[0019] In formula (1), X 1 and X 2 are each independently a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond or a carbamate bond. Among these, as X 1 , a single bond, an ether bond, an ester bond or a sulfonic acid ester bond is preferable, and as X 2 , a single bond, an ether bond or an ester bond is preferable.

[0020] In formula (1), R 1 is a hydrocarbyl group having 1 to 10 carbon atoms, a halogen atom other than an iodine atom, a nitro group or a cyano group, and the hydrocarbyl group may have at least one selected from a halogen atom, an oxygen atom, a sulfur atom and a nitrogen atom.

[0021] R 1 Specific examples of the halogen atom represented by are a fluorine atom, a chlorine atom, a bromine atom, etc. R 1The hydrocarbyl group represented by

[0022] In formula (1), R 2 may be a single bond or a hydrocarbylene group having 1 to 40 carbon atoms, and the hydrocarbylene group may contain at least one selected from an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom.

[0023] R 2The hydrocarbylene group represented by is may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include C1-C40 alkanediyl groups such as methylenediyl group, ethane-1,1-diyl group, ethane-1,2-diyl group, 1-methylethane-1,2-diyl group, 1-ethylethane-1,2-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-1,3-diyl group, 2-methylpropane-1,1-diyl group, butane-1,3-diyl group, butane-1,4-diyl group, butane-2,3-diyl group, 1,1-dimethylpropane-1,3-diyl group, 2,2-dimethylpropane-1,3-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, octadecane-1,18-diyl group, nonadecane-1,19-diyl group, eicosane-1,20-diyl group; C3-C40 cyclic saturated hydrocarbylene groups such as cyclopentanediyl group, cyclohexanediyl group, bicyclo[2.2.2]octanediy group, norbornanediy group, adamantanediy group; C2-C40 alkenediyl groups such as ethenediyl group, propenediyl group, butenediyl group; C2-C40 alkynediyl groups such as ethynediyl group, propynediyl group, butynediyl group; C3-C40 cyclic unsaturated aliphatic hydrocarbylene groups such as cyclohexenediyl group, bicyclo[2.2.2]octenediyl group, norbornenediyl group; C6-C40 arylene groups such as phenylene group, methylphenylene group, ethylphenylene group, n-propylphenylene group, isopropylphenylene group, n-butylphenylene group, isobutylphenylene group, sec-butylphenylene group, tert-butylphenylene group, naphthylene group, methylnaphthylene group, ethylnaphthylene group, 9,10-dihydro-9,10-ethanoanthracenediyl; and groups obtained by combining these.

[0024] In formula (1), Rf 1 ~Rf 4 are each independently a hydrogen atom, a fluorine atom or a trifluoromethyl group. However, when p is 0, at least one of Rf 3 and Rf 4 is a fluorine atom or a trifluoromethyl group, and when p is 1, at least one of Rf 1 ~Rf 4 is a fluorine atom or a trifluoromethyl group. Further, Rf 1 and Rf 2 may combine to form a carbonyl group.

[0025] Specific examples of the anion of the bis-onium salt include, but are not limited to, those shown below.

Chemical formula

[0026]

Chemical formula

[0027]

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[0028]

Chemical formula

[0029]

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[0030]

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[0031]

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[0042] [Chemistry]

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[0061]

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[0062] In formula (1), M + is a sulfonium cation or an iodonium cation. Two M +One may be a sulfonium cation and the other may be an iodonium cation, or both may be sulfonium cations, or both may be iodonium cations. Two Ms + When both are sulfonium cations, they may be the same as each other or different from each other. Also, two Ms + When both are iodonium cations, they may be the same as each other or different from each other.

[0063] As the sulfonium cation, those represented by the following formula (2) are preferred, and as the iodonium cation, those represented by the following formula (3) are preferred.

Chemical formula

[0064] In formulas (2) and (3), R 3 ~R 7 are each independently a halogen atom or a hydrocarbyl group having 1 to 20 carbon atoms which may contain a heteroatom.

[0065] R 3 ~R 7 Specific examples of the halogen atom represented by R

[0066] R 3 ~R 7The hydrocarbyl group having 1 to 20 carbon atoms represented by is may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include alkyl groups having 1 to 20 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-nonyl group, n-decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group; cyclic saturated hydrocarbyl groups having 3 to 20 carbon atoms such as cyclopropyl group, cyclopentyl group, cyclohexyl group, cyclopropylmethyl group, 4-methylcyclohexyl group, cyclohexylmethyl group, norbornyl group, adamantyl group; alkenyl groups having 2 to 20 carbon atoms such as vinyl group, propenyl group, butenyl group, hexenyl group; alkynyl groups having 2 to 20 carbon atoms such as ethynyl group, propynyl group, butynyl group; cyclic unsaturated aliphatic hydrocarbyl groups having 3 to 20 carbon atoms such as cyclohexenyl group, norbornenyl group; aryl groups having 6 to 20 carbon atoms such as phenyl group, methylphenyl group, ethylphenyl group, n-propylphenyl group, isopropylphenyl group, n-butylphenyl group, isobutylphenyl group, sec-butylphenyl group, tert-butylphenyl group, naphthyl group, methylnaphthyl group, ethylnaphthyl group, n-propylnaphthyl group, isopropylnaphthyl group, n-butylnaphthyl group, isobutylnaphthyl group, sec-butylnaphthyl group, tert-butylnaphthyl group; aralkyl groups having 7 to 20 carbon atoms such as benzyl group, phenethyl group; and groups obtained by combining these.

[0067] Further, 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, a sulfur atom, a nitrogen atom, or a 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, a sulfur atom, or a nitrogen atom. As a result, it may contain a hydroxy group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a mercapto group, a pentafluorosulfanyl 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)-O-C(=O)-), a haloalkyl group, etc.

[0068] Further, R 3 and R 4 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. At this time, as the ring, those having the structures shown below are preferable.

Chemical formula

[0069] M + Specific examples of the sulfonium cation represented by include, but are not limited to, those shown below.

Chemical formula

[0070]

Chemical formula

[0071]

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[0072]

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[0101] M + Specific examples of the iodonium cation represented by M include, but are not limited to, those shown below. [Chemical]

[0102] [Chemical]

[0103] Examples of the method for synthesizing the bis-onium salt include, for example, a method of performing salt exchange between a sulfonium salt or iodonium salt containing a halide anion and a diammonium salt containing a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonic acid anion structure bonded to the aromatic ring of the phenoxide anion structure.

[0104] In the resist material of the present invention, the content of the bis-onium salt is preferably 0.01 to 1000 parts by mass, more preferably 0.05 to 500 parts by mass, from the viewpoints of sensitivity and acid diffusion suppression effect, based on 100 parts by mass of the base polymer described below.

[0105] [Base Polymer] The base polymer contained in the resist material of the present invention contains a repeating unit containing an acid-labile group in the case of a positive resist material. As the repeating unit containing an acid-labile group, a repeating unit represented by the following formula (a1) (hereinafter, also referred to as repeating unit a1) or a repeating unit represented by formula (a2) (hereinafter, also referred to as repeating unit a2) is preferable. [Chemical formula]

[0106] In formulas (a1) and (a2), R A is independently a hydrogen atom or a methyl group. Y 1 is a single bond, a phenylene group or a naphthylene group, or a linking group having 1 to 12 carbon atoms containing at least one selected from an ester bond, an ether bond and a lactone ring, and the phenylene group, naphthylene group and linking group may have at least one selected from a hydroxy group, a saturated hydrocarbyloxy group having 1 to 8 carbon atoms and a saturated hydrocarbylcarbonyloxy group having 2 to 8 carbon atoms. Y 2 is a single bond or an ester bond. Y 3 is a single bond, an ether bond or an ester bond. R 11 and R 12 are each independently an acid-labile group. R 13is a saturated hydrocarbyl group having 1 to 4 carbon atoms, a halogen atom, a saturated hydrocarbylcarbonyl group having 2 to 5 carbon atoms, a cyano group or a saturated hydrocarbyloxycarbonyl group having 2 to 5 carbon atoms. R 14 is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and the alkanediyl group may contain an ether bond or an ester bond. a is an integer of 0 to 4.

[0107] Specific examples of the monomer that gives the repeating unit a1 include, but are not limited to, those shown below. In the following formulas, R A and R 11 are the same as described above.

Chemical formula

[0108]

Chemical formula

[0109]

Chemical formula

[0110] Specific examples of the monomer that gives the repeating unit a2 include, but are not limited to, those shown below. In the following formulas, R A and R 12 are the same as described above.

Chemical formula

[0111] Examples of the acid-labile group represented by R 11 and R 12 in the repeating units a1 and a2 include those described in, for example, JP-A-2013-80033 and JP-A-2013-83821.

[0112] Typically, specific examples of the acid-labile group include those represented by any of the following formulas (AL-1) to (AL-3).

Chemical formula

[0113] In formulas (AL-1) and (AL-2), R L1 and R L2 are each independently a hydrocarbyl group having 1 to 40 carbon atoms, and may contain heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, and a fluorine atom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. As the hydrocarbyl group, a saturated hydrocarbyl group having 1 to 40 carbon atoms is preferable, and a saturated hydrocarbyl group having 1 to 20 carbon atoms is more preferable.

[0114] In formula (AL-1), b is an integer from 0 to 10, and an integer from 1 to 5 is preferable.

[0115] In formula (AL-2), R L3 and R L4 are each independently a hydrogen atom or a hydrocarbyl group having 1 to 20 carbon atoms, and may contain heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, and a fluorine atom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. As the hydrocarbyl group, a saturated hydrocarbyl group having 1 to 20 carbon atoms is preferable. Further, any two of R L2 , R L3 and R L4 may be bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded or a carbon atom and an oxygen atom. As the ring, a ring having 4 to 16 carbon atoms is preferable, and an alicyclic ring is particularly preferable.

[0116] In formula (AL-3), R L5 , R L6 and R L7is, independently of each other, a hydrocarbyl group having 1 to 20 carbon atoms, and may contain heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and fluorine atoms. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. As the hydrocarbyl group, a saturated hydrocarbyl group having 1 to 20 carbon atoms is preferable. Also, R L5 、R L6 and R L7 Any two of them may be bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded. As the ring, a ring having 4 to 16 carbon atoms is preferable, and an alicyclic ring is particularly preferable.

[0117] The base polymer may contain a repeating unit b containing a phenolic hydroxy group as an adhesion group. Specific examples of the monomer that gives the repeating unit b include, but are not limited to, those shown below. In the following formula, R A is the same as described above.

Chemical formula

[0118] The base polymer may contain a repeating unit c containing a hydroxy group other than a phenolic hydroxy group, a lactone ring, a sultone ring, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonyl group, a sulfonyl group, a cyano group, or a carboxy group as another adhesion group. Specific examples of the monomer that gives the repeating unit c include, but are not limited to, those shown below. In the following formula, R A is the same as described above.

Chemical formula

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[0126] The base polymer may contain a repeating unit d derived from indene, benzofuran, benzothiophene, acenaphthylene, chromone, coumarin, norbornadiene, or a derivative thereof. Specific examples of the monomer that gives the repeating unit d include, but are not limited to, those shown below.

Chem.

[0127] The base polymer may contain a repeating unit e derived from styrene, vinylnaphthalene, vinylanthracene, vinylpyrene, methylene indane, vinylpyridine, or vinylcarbazole.

[0128] The base polymer may contain a repeating unit f derived from an onium salt containing a polymerizable unsaturated bond. Specific examples of preferred repeating unit f include a repeating unit represented by the following formula (f1) (hereinafter, also referred to as repeating unit f1), a repeating unit represented by the following formula (f2) (hereinafter, also referred to as repeating unit f2), a repeating unit represented by the following formula (f3) (hereinafter, also referred to as repeating unit f3), a repeating unit represented by the following formula (f4) (hereinafter, also referred to as repeating unit f4), and a repeating unit represented by the following formula (f5) (hereinafter, also referred to as repeating unit f5). Note that repeating units f1 to f5 may be used alone or in combination of two or more.

Chemical formula

[0129] In formulas (f1) to (f5), R A is independently a hydrogen atom or a methyl group.

[0130] In formulas (f1) to (f3), 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 or an ester bond. Z 3 is a single bond, -Z 31 -C(=O)-O-, -Z 31 -O- or -Z 31 -O-C(=O)-. Z 31represents an aliphatic hydrocarbylene group having 1 to 12 carbon atoms, a phenylene 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, an iodine atom, or a bromine atom. Z 4 is a methylene group, a 2,2,2-trifluoro-1,1-ethanediyl group, or a carbonyl group. 5 represents a single bond, a methylene group, an ethylene group, a phenylene group, a fluorinated phenylene group, a phenylene group substituted with a trifluoromethyl group, -OZ 51 -, -C(=O)-OZ 51 - or -C(=O)-NH-Z 51 -It is. Z 51 is an aliphatic hydrocarbylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a phenylene group substituted with a trifluoromethyl group, and may contain a carbonyl group, an ester bond, an ether bond, a halogen atom, or a hydroxy group. 1 , Z 11 , Z 31 and Z 51 The aliphatic hydrocarbylene group represented by the formula (I) may be saturated or unsaturated, and may be linear, branched, or cyclic.

[0131] In formulas (f4) and (f5), Z 6 is a single bond, a phenylene group, a naphthylene ring, an ester bond or an amide bond.

[0132] In formula (f4), Z 7A represents a single bond or a divalent organic group having 1 to 24 carbon atoms, which may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0133] Z 7AThe divalent organic group represented by the formula (I) may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include hydrocarbylene groups having 1 to 24 carbon atoms in which some or all of the hydrogen atoms have been substituted with iodine atoms or bromine atoms. Specific examples of the hydrocarbylene groups having 1 to 24 carbon atoms include 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, trimethylsilyl group, methyltri ... Alkanediyl groups such as decane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecane-1,17-diyl, octadecane-1,18-diyl, nonadecane-1,19-diyl, and eicosane-1,20-diyl; cyclopentanediyl, methylcyclopentanediyl, dimethylcyclopentanediyl, trimethylcyclopentanediyl, tetradecanediyl, and the like. Examples of the aryl group include cyclic saturated hydrocarbylene groups such as methylcyclopentanediyl, cyclohexanediyl, methylcyclohexanediyl, dimethylcyclohexanediyl, trimethylcyclohexanediyl, tetramethylcyclohexanediyl, norbornanediyl, and adamantanediyl; arylene groups such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, tert-butylnaphthylene, biphenyldiyl, methylbiphenyldiyl, and dimethylbiphenyldiyl; and groups obtained by combining these groups. 7A Some or all of the hydrogen atoms of Z may be substituted with a group containing at least one atom selected from an oxygen atom, a nitrogen atom and a sulfur atom;7A Part of the -CH2- may be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and as a result, it may contain a hydroxy group, an ester bond, an ether bond, an amide bond, a carbamate bond, a urea bond, etc.

[0134] In formula (f5), Z 7B is a monovalent organic group having 1 to 10 carbon atoms and may have at least one selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0135] Z 7BThe monovalent organic group represented by the formula (I) may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include hydrocarbyl groups having 1 to 10 carbon atoms in which some or all of the hydrogen atoms have been substituted with iodine or bromine atoms. Specific examples of the hydrocarbyl group having 1 to 10 carbon atoms include alkyl groups having 1 to 10 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, n-hexyl, n-octyl, n-nonyl, and n-decyl; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl groups. saturated cyclic hydrocarbyl groups having 3 to 10 carbon atoms, such as a norbornyl group, a cyclopropylmethyl group, a cyclopropylethyl group, a cyclobutylmethyl group, a cyclobutylethyl group, a cyclopentylmethyl group, a cyclopentylethyl group, a cyclohexylmethyl group, a cyclohexylethyl group, a methylcyclopropyl group, a methylcyclobutyl group, a methylcyclopentyl group, a methylcyclohexyl group, an ethylcyclopropyl group, an ethylcyclobutyl group, an ethylcyclopentyl group, or an ethylcyclohexyl group; alkenyl groups having 2 to 10 carbon atoms, such as an ethynyl group, a 1-propenyl group, a 2-propenyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, a nonenyl group, or a decenyl group; alkynyl groups having 2 to 10 carbon atoms, such as an ethynyl group, a propynyl group, a butynyl group, a pentynyl group, a hexynyl group, a heptynyl group, an octynyl group, a nonynyl group, or a decynyl group; cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group, ethylcyclopentenyl group, ethylcyclohexenyl group, Examples of such groups include cyclic unsaturated aliphatic hydrocarbyl groups having 3 to 10 carbon atoms, such as a norbornenyl group; aryl groups having 6 to 10 carbon atoms, such as a phenyl group, a methylphenyl group, an ethylphenyl group, an n-propylphenyl group, an isopropylphenyl group, an n-butylphenyl group, an isobutylphenyl group, a sec-butylphenyl group, a tert-butylphenyl group, and a naphthyl group; aralkyl groups having 7 to 10 carbon atoms, such as a benzyl group, a phenethyl group, a phenylpropyl group, and a phenylbutyl group; and groups obtained by combining these groups.Also, Z. 7B Some or all of the hydrogen atoms of 7B may be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and Z 7B Some of the -CH2- of may be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and as a result, it may contain a hydroxy group, an ester bond, an ether bond, an amide bond, a carbamate bond, a urea bond, etc.

[0136] In formulas (f4) and (f5), Z 8 is a single bond, an ether bond, an ester bond, a thioether bond, or an alkanediyl group having 1 to 6 carbon atoms.

[0137] In formula (f5), Z 9 is a trivalent organic group having 1 to 12 carbon atoms, and may have at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom. The trivalent organic group represented by Z 9 may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include a group obtained by removing one more hydrogen atom from a hydrocarbylene group having 1 to 12 carbon atoms. Specific examples of the hydrocarbylene group having 1 to 12 carbon atoms include those having 1 to 12 carbon atoms among the hydrocarbylene groups having 1 to 24 carbon atoms described above. Also, some or all of the hydrogen atoms of Z 9 may be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and some of the -CH2- of Z 9 may be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and as a result, it may contain a hydroxy group, an ester bond, an ether bond, an amide bond, a carbamate bond, a urea bond, etc.

[0138] In formulas (f1) to (f5), R 21 ~R 25are each independently a halogen atom or a hydrocarbyl group having 1 to 20 carbon atoms which may contain a heteroatom. Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include R 3 ~R 7 Examples of the hydrocarbyl group include the same as those exemplified above. In addition, 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, a sulfur atom, a nitrogen atom, or a halogen atom, and some of the -CH2- groups of the hydrocarbyl group may be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, the hydrocarbyl group may contain a hydroxy group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate ester bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride (-C(=O)-OC(=O)-), a haloalkyl group, or the like. Furthermore, R 23 and R 24 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, specific examples of the ring include R 3 and R 4 are bonded to each other to form a ring together with the sulfur atom to which they are bonded, the same as those exemplified above.

[0139] In formulas (f4) and (f5), R 26 are each independently a saturated hydrocarbyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, an iodine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group, or a nitro group.

[0140] In formulas (f4) and (f5), the circle R represents a (j+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms. Specific examples of the (j+2)-valent aromatic hydrocarbon group include groups obtained by eliminating (j+2) hydrogen atoms from aromatic hydrocarbons such as benzene and naphthalene.

[0141] In formulae (f4) and (f5), j's each independently represent an integer of 0 to 5.

[0142] In formula (f1), M - is a non-nucleophilic counter ion. Specific examples of the non-nucleophilic counter ion include halide ions such as chloride ion and bromide ion, fluoroalkylsulfonate ions such as triflate ion, 1,1,1-trifluoroethanesulfonate ion and nonafluorobutanesulfonate ion, arylsulfonate ions such as tosylate ion, benzenesulfonate ion, 4-fluorobenzenesulfonate ion and 1,2,3,4,5-pentafluorobenzenesulfonate ion, alkylsulfonate ions such as mesylate ion and butanesulfonate ion, imide ions such as bis(trifluoromethylsulfonyl)imide ion, bis(perfluoroethylsulfonyl)imide ion and bis(perfluorobutylsulfonyl)imide ion, and methide ions such as tris(trifluoromethylsulfonyl)methide ion and tris(perfluoroethylsulfonyl)methide ion.

[0143] Further specific examples of the non-nucleophilic counter ion include a sulfonate ion represented by the following formula (f1-1) in which the α-position is substituted with a fluorine atom, and a sulfonate ion represented by the following formula (f1-2) in which the α-position is substituted with a fluorine atom and the β-position is substituted with a trifluoromethyl group. [ka]

[0144] In formula (f1-1), R 31 is a hydrogen atom or a hydrocarbyl group having 1 to 20 carbon atoms, and the hydrocarbyl group may contain at least one selected from an ether bond, an ester bond, a carbonyl group, a lactone ring, and a fluorine atom. The hydrocarbyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include R in formula (1A') described below.fa1 Examples thereof include the same as those exemplified as the hydrocarbyl group represented by

[0145] In formula (f1-2), R 32 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 the hydrocarbylcarbonyl group may contain at least one selected from an ether bond, an ester bond, a carbonyl group, and a lactone ring. The hydrocarbyl moiety of the hydrocarbyl group and the hydrocarbylcarbonyl group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same as those exemplified as the hydrocarbyl group represented by R fa1 in formula (1A') described later.

[0146] Specific examples of the cation of the monomer that gives the repeating unit f1 include, but are not limited to, those shown below. In the following formulas, R A is the same as described above.

Chemical formula

[0147] Specific examples of the cations of the repeating units f2 to f5 include the same as those exemplified as the cations of the onium salts represented by formula (1).

[0148] Specific examples of the anion of the monomer that gives the repeating unit f2 include, but are not limited to, those shown below. In the following formulas, R A is the same as described above.

Chemical formula

[0149]

Chemical formula

[0150] [Chemistry]

[0151] [Chemistry]

[0152] [Chemistry]

[0153] [Chemistry]

[0154] [Chemistry]

[0155] [Chemistry]

[0156] [Chemistry]

[0157] [Chemistry]

[0158] [Chemistry]

[0159] [Chemistry]

[0160] [Chemistry]

[0161] [ka]

[0162] [ka]

[0163] Specific examples of the anion of the monomer that gives the repeating unit f3 include, but are not limited to, those shown below. A is the same as above. [ka]

[0164] Specific examples of the anion of the monomer that gives the repeating unit f4 or f5 include, but are not limited to, those shown below. A and X BI is the same as above. [ka]

[0165] [ka]

[0166] [ka]

[0167] [ka]

[0168] [ka]

[0169]

change

[0170]

change

[0171]

change

[0172]

change

[0173]

change

[0174]

change

[0175]

change

[0176]

change

[0177]

change

[0178]

change

[0179]

change

[0180]

Chem.

[0181]

Chem.

[0182]

Chem.

[0183]

Chem.

[0184]

Chem.

[0185]

Chem.

[0186]

Chem.

[0187]

Chem.

[0188]

Chem.

[0189] The repeating units f1 to f5 function as an acid generator. By bonding the 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, the LWR and CDU are improved by the uniform dispersion of the acid generator.

[0190] The base polymer for the positive resist material essentially requires the 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 repeating unit f is at least one selected from the repeating units f1 to f5, f = f1 + f2 + f3 + f4 + f5. Also, a1 + a2 + b + c + d + e + f = 1.0.

[0191] On the other hand, the base polymer for the negative resist material does not necessarily require an acid-labile group. Examples of such a base polymer include those containing the repeating unit b and, if necessary, further containing the 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 still 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 repeating unit f is at least one selected from the repeating units f1 to f5, f = f1 + f2 + f3 + f4 + f5. Also, b + c + d + e + f = 1.0.

[0192] Examples of the method for synthesizing the base polymer include, for example, a method in which a monomer that provides the repeating unit described above is heated in an organic solvent with the addition of a radical polymerization initiator to perform polymerization.

[0193] Specific examples of the organic solvent used during polymerization include toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, and the like. Specific 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, and the like. 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.

[0194] When copolymerizing a monomer containing a hydroxy group, the hydroxy group may be substituted with an acetal group that is easily deprotected by an acid such as an ethoxyethoxy group before polymerization and then deprotected with a weak acid and water after polymerization, or it may be substituted with an acetyl group, a formyl group, a pivaloyl group, etc. and then subjected to alkaline hydrolysis after polymerization.

[0195] When copolymerizing hydroxystyrene or hydroxyvinylnaphthalene, acetoxystyrene or acetoxyvinylnaphthalene may be used instead of hydroxystyrene or hydroxyvinylnaphthalene, and the acetoxy group may be deprotected by the above-mentioned alkaline hydrolysis after polymerization to obtain hydroxystyrene or hydroxyvinylnaphthalene.

[0196] As the base during alkaline hydrolysis, aqueous ammonia, triethylamine, etc. can be used. Also, 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.

[0197] The base polymer preferably has a polystyrene-equivalent weight average molecular weight (Mw) of 1,000 to 500,000, more preferably 2,000 to 30,000, as measured by gel permeation chromatography (GPC) using THF as a solvent. When Mw is within the above range, the heat resistance and solubility in an alkaline developer of the resist film are good.

[0198] Furthermore, when the molecular weight distribution (Mw / Mn) of the base polymer is broad, there are low molecular weight and high molecular weight polymers, so there is a risk that foreign matter may be seen on the pattern or the pattern shape may deteriorate 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 suitably used for fine pattern dimensions, the Mw / Mn of the base polymer is preferably narrowly dispersed at 1.0 to 2.0, particularly 1.0 to 1.5.

[0199] The base polymer may contain two or more polymers having different composition ratios, Mw, and Mw / Mn.

[0200] [Organic solvent] The resist material of the present invention may contain an organic solvent. The organic solvent is not particularly limited as long as each of the above-described components and each of the components described below can be dissolved therein. Specific examples of the organic solvent include ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone described in paragraphs

[0144] to

[0145] of JP-A-2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as γ-butyrolactone, and the like.

[0201] In the resist material of the present invention, the content of the organic solvent is preferably 100 to 10,000 parts by mass, more preferably 200 to 8,000 parts by mass, based on 100 parts by mass of the base polymer. The organic solvent may be used alone or in combination of two or more.

[0202] [Quencher] The resist material of the present invention may contain a quencher. The quencher means a compound that can prevent the diffusion to the unexposed portion by trapping the acid generated from the acid generator in the resist material.

[0203] Examples of the quencher include conventional basic compounds. Specific examples of conventional basic compounds include primary, secondary, and tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxy group, nitrogen-containing compounds having a sulfonyl group, nitrogen-containing compounds having a hydroxy group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amides, imides, and carbamates. Particularly preferred are the primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of JP 2008-111103 A, particularly amine compounds having a hydroxy group, an ether bond, an ester bond, a lactone ring, a cyano group, or a sulfonate ester bond, and compounds having a carbamate bond described in Japanese Patent No. 3790649 A. Addition of such basic compounds can, for example, further suppress the diffusion rate of acid in the resist film or correct the shape.

[0204] Further, examples of the quencher include onium salts such as sulfonium salts, iodonium salts, and ammonium salts of sulfonic acids, carboxylic acids, or fluorinated alkoxides that are not fluorinated at the α-position, as described in JP 2008-158339 A. Sulfonic acids, imide acids, or methide acids that are fluorinated at the α-position are necessary for deprotecting the acid labile group of a carboxylic acid ester, and salt exchange with the onium salt releases sulfonic acids, carboxylic acids, or fluorinated alcohols that are not fluorinated at the α-position. Sulfonic acids, carboxylic acids, and fluorinated alcohols that are not fluorinated at the α-position do not undergo a deprotection reaction, and therefore function as quenchers.

[0205] Specific examples of such quenchers include a compound represented by the following formula (4) (onium salt of sulfonic acid not fluorinated at the α-position), a compound represented by the following formula (5) (onium salt of carboxylic acid), and a compound represented by the following formula (6) (onium salt of alkoxide). [ka]

[0206] In formula (4), R 101 represents 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 carbon atom at the α-position of the sulfo group is substituted with a fluorine atom or a fluoroalkyl group.

[0207] R 101 The hydrocarbyl group having 1 to 40 carbon atoms represented by the formula (I) may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 40 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, an n-hexyl group, an n-octyl group, a 2-ethylhexyl group, an n-nonyl group, and an n-decyl group; a cyclopentyl group, a cyclohexyl group, a cyclopentylmethyl group, a cyclopentylethyl group, a cyclopentylbutyl group, a cyclohexylmethyl group, a cyclohexylethyl group, a cyclohexylbutyl group, a norbornyl group, and a tricyclo[5.2.1.0] 2,6 ]Cyclic saturated hydrocarbyl groups having 3 to 40 carbon atoms such as a decyl group, an adamantyl group, and an adamantylmethyl group; alkenyl groups having 2 to 40 carbon atoms such as a vinyl group, an allyl group, a propenyl group, a butenyl group, and a hexenyl group; cyclic unsaturated aliphatic hydrocarbyl groups having 3 to 40 carbon atoms such as a cyclohexenyl group; phenyl group, naphthyl group, alkylphenyl groups (2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-tert-butylphenyl group, Examples of aryl groups include aryl groups having 6 to 40 carbon atoms such as arylphenyl groups (e.g., 2,4-n-butylphenyl group, 4-n-butylphenyl group), di- or trialkylphenyl groups (e.g., 2,4-dimethylphenyl group, 2,4,6-triisopropylphenyl group), alkylnaphthyl groups (e.g., methylnaphthyl group, ethylnaphthyl group), and dialkylnaphthyl groups (e.g., dimethylnaphthyl group, diethylnaphthyl group); and aralkyl groups having 7 to 40 carbon atoms such as benzyl group, 1-phenylethyl group, and 2-phenylethyl group.

[0208] Also, 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, a sulfur atom, a nitrogen atom, or a 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, a sulfur atom, or a nitrogen atom. As a result, it may contain a hydroxy 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)-O-C(=O)-), a haloalkyl group, etc. Specific examples of the hydrocarbyl group containing a heteroatom include heteroaryl groups such as thienyl group; alkoxyphenyl groups such as 4-hydroxyphenyl group, 4-methoxyphenyl group, 3-methoxyphenyl group, 2-methoxyphenyl group, 4-ethoxyphenyl group, 4-tert-butoxyphenyl group, 3-tert-butoxyphenyl group, etc.; alkoxynaphthyl groups such as methoxynaphthyl group, ethoxynaphthyl group, n-propoxynaphthyl group, n-butoxynaphthyl group, etc.; dialkoxynaphthyl groups such as dimethoxynaphthyl group, diethoxynaphthyl group, etc.; aryloxoalkyl groups such as 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl group, 2-(1-naphthyl)-2-oxoethyl group, 2-(2-naphthyl)-2-oxoethyl group, etc.

[0209] In formula (5), R 102 is a hydrocarbyl group having 1 to 40 carbon atoms which may contain a heteroatom. Specific examples of the hydrocarbyl group represented by R 102 are the same as those exemplified as the hydrocarbyl group represented by R 101 In addition, as other specific examples, fluorinated alkyl groups such as trifluoromethyl group, trifluoroethyl group, 2,2,2-trifluoro-1-methyl-1-hydroxyethyl group, 2,2,2-trifluoro-1-(trifluoromethyl)-1-hydroxyethyl group, etc.; fluorinated aryl groups such as pentafluorophenyl group, 4-trifluoromethylphenyl group, etc. may also be mentioned.

[0210] In formula (6), R 103is a saturated hydrocarbyl group having 1 to 8 carbon atoms and at least three fluorine atoms, or an aryl group having 6 to 10 carbon atoms and at least three fluorine atoms, which may contain a nitro group.

[0211] In equations (4), (5) and (6), Mq + is an onium cation. The onium cation is preferably a sulfonium cation, an iodonium cation, or an ammonium cation, and more preferably a sulfonium cation. Specific examples of the sulfonium cation include those represented by M in the description of formula (1). + Examples of the sulfonium cation represented by the formula: include the same as those exemplified above.

[0212] As the quencher, a sulfonium salt of an iodinated benzene ring-containing carboxylic acid represented by the following formula (7) can also be suitably used. [ka]

[0213] In formula (7), x is an integer of 1 to 5. y is an integer of 0 to 3. z is an integer of 1 to 3.

[0214] In formula (7), R 111 represents a hydroxy group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, a nitro group, a cyano group, or 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, in which some or all of the hydrogen atoms may be substituted with halogen atoms, or -N(R 111A )-C(=O)-R 111B or -N(R 111A )-C(=O)-OR 111B R 111A is a hydrogen atom or a saturated hydrocarbyl group having 1 to 6 carbon atoms. 111Bis a saturated hydrocarbyl group having 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbyl group having 2 to 8 carbon atoms. When y and / or z is 2 or more, each R 111 may be the same as or different from each other.

[0215] In formula (7), L 1 is a single bond or a (z + 1)-valent linking group having 1 to 20 carbon atoms, and may contain at least one selected from an ether bond, a carbonyl group, an ester bond, an amide bond, a sultone ring, a lactam ring, a carbonate bond, a halogen atom, a hydroxy group, and a carboxy group. The saturated hydrocarbyl group, saturated hydrocarbyloxy group, saturated hydrocarbylcarbonyloxy group, and saturated hydrocarbylsulfonyloxy group may be linear, branched, or cyclic.

[0216] In formula (7), R 112 , R 113 and R 114 are each independently a halogen atom or a hydrocarbyl group having 1 to 20 carbon atoms which may contain a hetero atom. 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 groups represented by R 3 to R 7 in the descriptions of formulas (2) and (3).

[0217] Specific examples of the compound represented by formula (7) include those described in JP-A-2017-219836 and JP-A-2021-91666.

[0218] As another example of the quencher, a polymer-type quencher described in JP-A-2008-239918 can be mentioned. This enhances the rectangularity of the resist pattern by orienting on the resist film surface. The polymer-type quencher also has an effect of preventing film loss of the pattern and rounding of the pattern top when a protective film for liquid immersion exposure is applied.

[0219] Furthermore, betaine-type sulfonium salts described in Japanese Patent No. 6848776 and Japanese Patent Application Laid-Open No. 2020-37544, fluorine-free methide acids described in Japanese Patent Application Laid-Open No. 2020-55797, sulfonium salts of sulfonamides described in Japanese Patent Application Laid-Open No. 5807552, sulfonium salts of sulfonamides containing iodine atoms described in Japanese Patent Application Laid-Open No. 2019-211751, and acid generators that generate phenols, halogens, and carbonic acid can also be used as quenchers.

[0220] When the resist composition of the present invention contains the quencher, the content thereof is preferably 0 to 5 parts by mass, more preferably 0 to 4 parts by mass, relative to 100 parts by mass of the base polymer. The quencher may be used alone or in combination of two or more types.

[0221] [Other ingredients] In addition to the above-mentioned components, the composition may contain acid generators other than the salt represented by formula (1) (hereinafter referred to as other acid generators), surfactants, dissolution inhibitors, crosslinking agents, water repellency improvers, acetylene alcohols, etc.

[0222] Examples of the other acid generator include compounds (photoacid generators) that generate acid in response to actinic rays or radiation. The photoacid generator component may be any compound that generates an acid upon exposure to high-energy rays, but acid generators that generate sulfonic acid, imide acid, or methide acid are preferred. Specific examples of suitable photoacid generators include sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, and oxime-O-sulfonate-type acid generators. Specific examples of the acid generators include those described in paragraphs

[0122] to

[0142] of JP 2008-111103 A, JP 2018-5224 A, and JP 2018-25789 A. When the resist material of the present invention contains another acid generator, the content thereof is preferably 0 to 200 parts by weight, and more preferably 0.1 to 100 parts by weight, per 100 parts by weight of the base polymer.

[0223] Specific examples of the surfactant include those described in paragraphs

[0165] to

[0166] of JP-A-2008-111103. By adding the surfactant, the coatability of the resist material can be further improved or controlled. When the resist material of the present invention contains a surfactant, its content is preferably 0.0001 to 10 parts by mass with respect to 100 parts by mass of the base polymer. The surfactant may be used alone or in combination of two or more.

[0224] When the resist material of the present invention is a positive type, by blending a dissolution inhibitor, the difference in dissolution rate between the exposed portion and the unexposed portion can be further increased, and the resolution can be further improved. Specific examples of the dissolution inhibitor include a compound having a molecular weight preferably of 100 to 1000, more preferably 150 to 800, and containing two or more phenolic hydroxy groups in the molecule, and in which the hydrogen atoms of the phenolic hydroxy groups are substituted as a whole by acid-labile groups at a ratio of 0 to 100 mol%, or a compound having a carboxy group in the molecule, and in which the hydrogen atoms of the carboxy group are substituted as a whole by acid-labile groups at an average ratio of 50 to 100 mol%. Specifically, there can be mentioned compounds in which the hydrogen atoms of the hydroxy groups and carboxy groups of bisphenol A, trisphenol, phenolphthalein, cresol novolak, naphthalene carboxylic acid, adamantane carboxylic acid, and cholic acid are substituted by acid-labile groups, etc., for example, those described in paragraphs

[0155] to

[0178] of JP-A-2008-122932.

[0225] When the resist material of the present invention is a positive type and contains the dissolution inhibitor, its content is preferably 0 to 50 parts by mass, more preferably 5 to 40 parts by mass with respect to 100 parts by mass of the base polymer. The dissolution inhibitor may be used alone or in combination of two or more.

[0226] On the one hand, when the resist material of the present invention is negative, a negative pattern can be obtained by adding a crosslinking agent to reduce the dissolution rate of the exposed area. Specific examples of the crosslinking agent include epoxy compounds, melamine compounds, guanamine compounds, glycoluril compounds or urea compounds substituted with at least one group selected from a methylol group, an alkoxymethyl group and an acyloxymethyl group, isocyanate compounds, azide compounds, compounds containing a double bond such as an alkenyloxy group, and the like. These may be used as additives, or may be introduced as pendant groups into the polymer side chain. Further, a compound containing a hydroxy group can also be used as a crosslinking agent.

[0227] Specific examples of the epoxy compound include tris(2,3-epoxypropyl) isocyanurate, trimethylolmethane triglycidyl ether, trimethylolpropane triglycidyl ether, triethylolethane triglycidyl ether and the like.

[0228] Specific examples of the melamine compound include hexamethylol melamine, hexamethoxymethyl melamine, a compound or a mixture thereof in which 1 to 6 methylol groups of hexamethylol melamine are methoxymethylated, hexamethoxyethyl melamine, hexaacyloxymethyl melamine, a compound or a mixture thereof in which 1 to 6 methylol groups of hexamethylol melamine are acyloxymethylated, and the like.

[0229] Specific examples of the guanamine compound include tetramethylol guanamine, tetramethoxymethyl guanamine, a compound or a mixture thereof in which 1 to 4 methylol groups of tetramethylol guanamine are methoxymethylated, tetramethoxyethyl guanamine, tetraacyloxy guanamine, a compound or a mixture thereof in which 1 to 4 methylol groups of tetramethylol guanamine are acyloxymethylated, and the like.

[0230] Specific examples of the glycoluril compound include tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, a compound or mixture thereof in which 1 to 4 of the methylol groups of tetramethylol glycoluril are methoxymethylated, a compound or mixture thereof in which 1 to 4 of the methylol groups of tetramethylol glycoluril are acyloxymethylated, and the like. Specific examples of the urea compound include tetramethylol urea, tetramethoxymethyl urea, a compound or mixture thereof in which 1 to 4 of the methylol groups of tetramethylol urea are methoxymethylated, tetramethoxyethyl urea, and the like.

[0231] Specific examples of the isocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, and the like.

[0232] Specific examples of the azide compound include 1,1'-biphenyl-4,4'-bisazide, 4,4'-methylidenebisazide, 4,4'-oxybisazide, and the like.

[0233] Specific examples of the compound containing an 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, trimethylolpropane trivinyl ether, and the like.

[0234] When the resist composition of the present invention is a negative resist composition and contains the crosslinking agent, the content thereof is preferably 0.1 to 50 parts by mass, more preferably 1 to 40 parts by mass, per 100 parts by mass of the base polymer. The crosslinking agents may be used alone or in combination of two or more.

[0235] The water repellency improver improves the water repellency of the resist film surface and can be used in immersion lithography without a top coat. Preferred examples of the water repellency improver include polymers containing fluorinated alkyl groups and polymers containing a 1,1,1,3,3,3-hexafluoro-2-propanol residue with a specific structure, and examples thereof are described in JP-A Nos. 2007-297590 and 2008-111103. The water repellency improver must be soluble in an alkaline developer or an organic solvent developer. The water repellency improver having the specific 1,1,1,3,3,3-hexafluoro-2-propanol residue described above has good solubility in the developer. As a water repellency improver, a polymer containing a repeating unit containing an amino group or an amine salt is highly effective in preventing the evaporation of acid during PEB and preventing poor opening of the hole pattern after development. When the resist composition of the present invention contains the water repellency improver, the content thereof is preferably 0 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, relative to 100 parts by mass of the base polymer. The water repellency improver may be used alone or in combination of two or more. It may also be used.

[0236] Specific examples of the acetylene alcohols include those described in paragraphs

[0179] to

[0182] of JP 2008-122932 A. When the resist material of the present invention contains the acetylene alcohols, the content thereof is preferably 0 to 5 parts by mass per 100 parts by mass of the base polymer. The acetylene alcohols may be used alone or in combination of two or more.

[0237] [Pattern formation method] When the 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 can include a method comprising the steps of forming a resist film on a substrate using the resist material, exposing the resist film to high-energy radiation, and developing the exposed resist film using a developer.

[0238] First, the resist material of the present invention is applied to a substrate for integrated circuit manufacturing (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective coating, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, MoSi2, SiO2, etc.) by an appropriate coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc., to a coating thickness of 0.01 to 2 μm. This is then prebaked 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.

[0239] Next, the resist film is exposed to high-energy radiation. Specific examples of the high-energy radiation include ultraviolet radiation, far ultraviolet radiation, EB, EUV radiation with a wavelength of 3 to 15 nm, X-rays, soft X-rays, excimer laser light, gamma rays, and synchrotron radiation. When ultraviolet radiation, far ultraviolet radiation, EUV radiation, X-rays, soft X-rays, excimer laser light, gamma rays, and synchrotron radiation are used as the high-energy radiation, the exposure dose is preferably 1 to 200 mJ / cm, either directly or using a mask for forming a desired pattern. 2 approximately, more preferably 10 to 100 mJ / cm 2 When EB is used as the high energy beam, the exposure dose is preferably 0.1 to 300 μC / cm 2 approximately, more preferably 0.5 to 200 μC / cm 2The resist material of the present invention is particularly suitable for fine patterning using high-energy rays such as KrF excimer laser light, ArF excimer laser light, EB, EUV, X-rays, soft X-rays, γ-rays, and synchrotron radiation, and is particularly suitable for fine patterning using EB or EUV.

[0240] After exposure, PEB may or may not be performed on a hot plate or in an oven, preferably at 30 to 150° C. for 10 seconds to 30 minutes, more preferably at 50 to 120° C. for 30 seconds to 20 minutes.

[0241] After exposure or PEB, the exposed resist film is developed using a developer of an alkaline aqueous solution of 0.1 to 10% by weight, preferably 2 to 5% by weight, 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 a conventional method such as dipping, puddling, or spraying, to form the desired pattern. In the case of a positive resist material, the irradiated portion dissolves in the developer, while the unexposed portion remains insoluble, forming the desired positive pattern on the substrate. In the case of a negative resist material, the opposite is true: the irradiated portion becomes insoluble in the developer, while the unexposed portion dissolves.

[0242] A negative pattern can also be obtained by organic solvent development using a positive resist material containing a base polymer containing an acid labile group. Specific examples of the developer used in this case 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 crotonate, and ethyl crotonate. Examples of organic solvents 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 phenylacetate, and 2-phenylethyl acetate. These organic solvents may be used alone or in combination of two or more.

[0243] After the development is completed, the resist film is rinsed. A solvent that is miscible with the developer but does not dissolve the resist film is preferred as the rinse solution. Preferred examples of such solvents include alcohols having 3 to 10 carbon atoms, ether compounds having 8 to 12 carbon atoms, alkanes, alkenes, alkynes, and aromatic solvents having 6 to 12 carbon atoms.

[0244] Specific examples of the alcohol having 3 to 10 carbon atoms 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, and 3-hexanol. Examples of the alcohol 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.

[0245] Specific examples of the ether compound 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.

[0246] Specific examples of the alkanes having 6 to 12 carbon atoms include hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, cyclononane, etc. Specific examples of the alkenes having 6 to 12 carbon atoms include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, cyclooctene, etc. Specific examples of the alkynes having 6 to 12 carbon atoms include hexyne, heptine, octyne, etc.

[0247] Specific examples of the aromatic solvent include toluene, xylene, ethylbenzene, isopropylbenzene, tert-butylbenzene, and mesitylene.

[0248] Rinsing can reduce the occurrence of resist pattern collapse and defects. Rinsing is not always necessary, and not performing rinsing can reduce the amount of solvent used.

[0249] The developed hole or trench pattern can also be shrunk using thermal flow, RELACS, or DSA. A shrink agent is applied to the hole pattern, and the diffusion of an acid catalyst from the resist film during baking causes crosslinking of the shrink agent on the surface of the resist film, resulting in adhesion of the shrink agent to the sidewalls 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. Excess shrink agent is removed, and the hole pattern is shrunk. [Example]

[0250] The present invention will be specifically explained below by showing synthesis examples, examples and comparative examples, but the present invention is not limited to the following examples.

[0251] The structures of the bis-onium salts PAG-PDQ-1 to PAG-PDQ-10, which are acid generators and quenchers used in the resist materials, are shown below. [ka]

[0252] [ka]

[0253] [ka]

[0254] [ka]

[0255] [ka]

[0256] [Synthesis Example] Synthesis of base polymers (polymers P-1 to P-5) Each monomer was combined and copolymerized in THF solvent, then added to methanol. The precipitated solid was washed with hexane, isolated, and dried to obtain the base polymers (polymers P-1 to P-5) with the following compositions. The resulting base polymers had the following compositions: 1 Mw and Mw / Mn were confirmed by H-NMR and GPC (solvent: THF, standard: polystyrene). [ka]

[0257] [Examples 1 to 17, Comparative Examples 1 to 3] Preparation and Evaluation of Resist Materials (1) Preparation of resist material A resist material was prepared by dissolving each component according to the composition shown in Table 1 and filtering the solution through a 0.2 μm filter.

[0258] In Table 1, the components are as follows: Organic solvent: PGMEA (propylene glycol monomethyl ether acetate) EL (Ethyl lactate) DAA (diacetone alcohol)

[0259] Comparative acid generator and quencher: cPAG-PDQ-1 [ka]

[0260] Comparative acid generator: cPAG-1 [ka]

[0261] Blend acid generator: bPAG-1, bPAG-2

Chem.

[0262] Blend quencher: bPDQ-1

Chem.

[0263] Comparative quencher: cPDQ-1

Chem.

[0264] (2) EUV Lithography Evaluation Each resist material shown in Table 1 was spin-coated on a Si substrate on which a silicon-containing spin-on hard mask SHB-A940 (silicon content: 43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. was formed with a film thickness of 20 nm, and pre-baked at 105 °C for 60 seconds using a hot plate to produce a resist film with a film thickness of 40 nm. The resist film was exposed using an EUV scanner NXE3400 (NA 0.33, σ 0.9 / 0.7, dipole illumination) manufactured by ASML, PEB was performed at the temperature described in Table 1 for 60 seconds on a hot plate, and development was performed for 30 seconds with a 2.38% by mass TMAH aqueous solution to form a line and space with a pitch of 32 nm and a line width of 16 nm. Examples 1 to 16 and Comparative Examples 1 and 2 are positive resist materials, and Example 17 and Comparative Example 3 are negative resist materials. Using a length measurement SEM (CG6300) manufactured by Hitachi High-Tech Corporation, the exposure dose at which a line pattern was formed with a dimension of 16 nm ± 1.6 nm was determined, and the LWR of the line pattern at this exposure dose was measured. The results are shown in Table 1.

[0265]

Table 1

[0266] From the results shown in Table 1, it was found that the resist material of the present invention containing a bis-onium salt including a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonate anion structure bonded to the aromatic ring of the phenoxide anion structure and an onium cation has high sensitivity and good LWR.

Claims

1. A resist material comprising a divalent anion having a phenoxide anion structure substituted with an iodine atom and a fluorosulfonate anion structure bonded to the aromatic ring of the phenoxide anion structure, and an onium cation.

2. The resist material according to claim 1, wherein the bis-onium salt is represented by the following formula (1). 【化1】 (In the formula, m is an integer of 1 to 4. n is an integer of 0 to 3. However, 1 ≤ m + n ≤ 4. p is 0 or 1.) X 1 and X 2 is each independently a single bond, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond or a carbamate bond. R 1 represents a hydrocarbyl group having 1 to 10 carbon atoms, a halogen atom other than an iodine atom, a nitro group, or a cyano group, and the hydrocarbyl group may have at least one atom selected from a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom. R 2 is a single bond or a hydrocarbylene group having 1 to 40 carbon atoms, and the hydrocarbylene group may contain at least one selected from an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. Rf 1 ~Rf 4 are each independently a hydrogen atom, a fluorine atom or a trifluoromethyl group. However, when p is 0, at least one of Rf 3 and Rf 4 is a fluorine atom or a trifluoromethyl group, and when p is 1, at least one of Rf 1 ~Rf 4 is a fluorine atom or a trifluoromethyl group. Further, Rf 1 and Rf 2 may combine to form a carbonyl group. M + is a sulfonium cation or an iodonium cation.)

3. The resist material according to claim 1, further comprising a base polymer.

4. The resist material according to claim 3, wherein the base polymer contains a repeating unit represented by the following formula (a1) or (a2). 【Chemistry 2】 (In the formula, R A are each independently a hydrogen atom or a methyl group. Y 1 represents a single bond, a phenylene group, a naphthylene group, or a linking group having 1 to 12 carbon atoms which contains at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, naphthylene group, and linking group may contain at least one selected from a hydroxy group, a saturated hydrocarbyloxy group having 1 to 8 carbon atoms, and a saturated hydrocarbylcarbonyloxy group having 2 to 8 carbon atoms. Y 2 is a single bond or an ester bond. Y 3 is a single bond, an ether bond or an ester bond. R 11 and R 12 are each independently an acid-labile group. R 13 is a saturated hydrocarbyl group having 1 to 4 carbon atoms, a halogen atom, a saturated hydrocarbylcarbonyl group having 2 to 5 carbon atoms, a cyano group or a saturated hydrocarbyloxycarbonyl group having 2 to 5 carbon atoms. R 14 is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and the alkanediyl group may contain an ether bond or an ester bond. a is an integer of 0 to 4.)

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

6. The resist material according to claim 3, wherein the base polymer does not contain an acid-labile group.

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

8. The resist material according to claim 1, further comprising an organic solvent.

9. The resist material according to claim 1, further comprising a quencher.

10. The resist material according to claim 1, further comprising an acid generator.

11. The resist material according to claim 1, further comprising a surfactant.

12. A pattern forming method comprising the steps of forming a resist film on a substrate using the resist material according to any one of claims 1 to 11, exposing the resist film with high-energy rays, and developing the exposed resist film using a developer.

13. The pattern forming method according to claim 12, wherein the high-energy rays are ArF excimer laser light having a wavelength of 193 nm, KrF excimer laser light having a wavelength of 248 nm, an electron beam, or extreme ultraviolet light having a wavelength of 3 to 15 nm.

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