Positive resist material and pattern forming method

Abstract

The invention relates to a positive resist material and a pattern forming method. The present invention addresses the problem of providing: a positive resist material which has higher sensitivity and resolution than known positive resist materials, small edge roughness and dimensional variation, and good pattern shape after exposure; and a pattern forming method. The solution of the present invention is a positive resist material comprising a base polymer that contains a repeating unit (a) having a substituted or unsubstituted carboxyl group and a substituted or unsubstituted phenolic hydroxyl group, however, the repeating unit (a) has at least one selected from the group consisting of an unsubstituted carboxyl group and an unsubstituted phenolic hydroxyl group, and the repeating unit (a) has at least one selected from the group consisting of a substituted or unsubstituted carboxyl group and a substituted or unsubstituted phenolic hydroxyl group. A repeating unit (b) having an acid-labile group; and a repeating unit (c) having a sulfonium salt or salt structure of sulfonic acid bonded to the polymer main chain.

Description

Technical Field

[0001] The present invention relates to a positive resist material and a pattern forming method. Background Art

[0002] With the high integration and high speed of LSI, the miniaturization of pattern rules is progressing rapidly. With the popularization of 5G high-speed communication and artificial intelligence (AI), high-performance devices for processing them have become necessary. As for the most advanced miniaturization technology, mass production of 5nm node and 3nm node devices using extreme ultraviolet (EUV) lithography with a wavelength of 13.5nm is underway. In addition, the next generation of 2nm node devices and the next generation of There is also research on EUV lithography in the node. IMEC in Belgium has shown device development.

[0003] As the miniaturization progresses, the blurring of the image due to the diffusion of acid becomes a problem. In order to ensure the resolution of fine patterns after the processing size of 45nm, in addition to the improvement of the dissolution contrast proposed in the past, it has been proposed that the control of acid diffusion is also important (Non-Patent Document 1). However, chemically amplified resist materials improve sensitivity and contrast by acid diffusion, so if the post-exposure baking (PEB) temperature is reduced and the time is shortened to suppress the acid diffusion to the limit, the sensitivity and contrast will be significantly reduced.

[0004] There is a triangular trade-off between sensitivity, resolution, and edge roughness. In order to improve resolution, it is necessary to suppress acid diffusion, but if the acid diffusion distance is shortened, the sensitivity will decrease.

[0005] Adding an acid generator that generates a bulky acid is effective for inhibiting acid diffusion. In response to this, it has been proposed that the polymer contain repeating units from an onium salt having a polymerizable unsaturated bond. In this case, the polymer also functions as an acid generator (polymer-bonded acid generator). In Patent Document 1, it has been proposed that a specific sulfonium salt or iodonium salt having a polymerizable unsaturated bond that generates sulfonic acid be used. In Patent Document 2, it has been proposed that a sulfonium salt in which sulfonic acid is directly bonded to the main chain be used.

[0006] Some people have proposed a resist material to which a polymer-bonded acid generator having an onium salt structure in which an anion having an iodine atom is bonded to the main chain is added (Patent Document 3). Due to the large absorption of EUV by iodine atoms, the efficiency of the acid generator decomposition during exposure becomes higher, resulting in high sensitivity. The amount of photon absorption increases, which can improve the physical contrast.

[0007] In order to control the charge of carbon powder particles, a polymer obtained by copolymerizing vinyl salicylic acid has been proposed (Patent Document 4). In order to improve the alkali solubility, a resist material using a polymer into which vinyl salicylic acid has been introduced has been proposed (Patent Document 5).

[0008] Prior art literature

[0009] Patent Literature

[0010] [Patent Document 1] Japanese Patent Application Publication No. 2006-045311

[0011] [Patent Document 2] Japanese Patent Application Publication No. 2006-178317

[0012] [Patent Document 3] Japanese Patent Application Publication No. 2018-197853

[0013] [Patent Document 4] Japanese Patent Application Publication No. 2011-137947

[0014] [Patent Document 5] Japanese Patent Application Publication No. 2023-131926

[0015] Non-patent literature

[0016] [Non-patent document 1] SPIE Vol.6520 65203L-1 (2007) Summary of the invention

[0017] [Problems to be solved by the invention]

[0018] There is a demand for the development of a positive resist material that has a higher sensitivity than known positive resist materials and can improve the line width roughness (LWR) of a line pattern and the dimension uniformity (CDU) of a hole pattern.

[0019] The present invention is made in view of the above situation, and its purpose is to provide a positive resist material and a pattern forming method which have higher sensitivity and higher resolution than known positive resist materials, and have a small LWR, good CDU, and good pattern shape after exposure.

[0020] [Methods to solve the problem]

[0021] The inventors of this application have repeatedly studied in order to obtain the high resolution expected in recent years, and the positive resist material with small LWR and good CDU. As a result, it is found that for this purpose, the acid diffusion distance must be shortened to the limit. By using a polymer with a sulfonium salt or iodonium salt structure of sulfonic acid bonded to the polymer main chain as a base polymer, the acid diffusion can be made very small. In addition, the introduction of iodine atoms in the acid generator to improve the physical contrast caused by the large absorption of photons and the reduction of image blur caused by the reduction of the diffusion of secondary electrons by direct excitation are effective. However, the introduction of iodine atoms into the acid generator will lead to a decrease in alkali solubility, and there is a possibility of generating residues in the interval part of the pattern. In the aforementioned polymer, a polymer having repeating units of substituted or unsubstituted carboxyl groups and substituted or unsubstituted phenolic hydroxyl groups (however, having at least one selected from unsubstituted carboxyl groups and unsubstituted phenolic hydroxyl groups) is introduced. This prevents swelling while increasing the alkali dissolution rate, so that LWR and CDU are good. In particular, it is believed that when combined with an acid generator having an iodine atom, it is effective as a base polymer of a chemically amplified positive resist material in which residue defects do not occur in the spacer portion.

[0022] Then, it is believed that in order to improve the dissolution contrast, by introducing a repeating unit in which the hydrogen atoms of a carboxyl group or a phenolic hydroxyl group are replaced by an acid-labile group, high sensitivity can be obtained and the contrast of the alkali dissolution rate before and after exposure can be greatly improved. The high sensitivity and the effect of inhibiting acid diffusion are high, and the resolution is high. The pattern shape, edge roughness and dimensional deviation after exposure are small and good. In particular, it is an ideal positive resist material as a fine pattern forming material for ultra-LSI manufacturing or photomask, and the present invention has been completed.

[0023] That is, the present invention provides the following positive resist material and pattern forming method.

[0024] 1. A positive resist material, comprising a base polymer, wherein the base polymer contains:

[0025] A repeating unit a having a substituted or unsubstituted carboxyl group and a substituted or unsubstituted phenolic hydroxyl group, wherein the repeating unit a has at least one selected from the group consisting of an unsubstituted carboxyl group and an unsubstituted phenolic hydroxyl group,

[0026] a repeating unit b having an acid-labile group, and

[0027] The repeating unit c has a sulfonium salt or iodonium salt structure of a sulfonic acid bonded to the main chain of the polymer.

[0028] 2. The positive resist material according to 1, wherein the repeating unit a is represented by the following formula (a);

[0029]

[0030] In the formula, k is 0 or 1; m is an integer from 1 to 4; n is an integer from 0 to 4;

[0031] R A is a hydrogen atom or a methyl group;

[0032] X 1 is a single bond or an ester bond;

[0033] X 2 It is a single bond, a saturated alkylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group;

[0034] X 3 is a single bond, an ester bond, an ether bond or a carbonyl group;

[0035] R 1 is an alkyl group having 1 to 4 carbon atoms or a halogen atom;

[0036] R 2 is a hydrogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 7 carbon atoms, or a saturated hydrocarbon oxycarbonyl group having 2 to 7 carbon atoms;

[0037] R 3 is a hydrogen atom, a saturated hydrocarbon group having 1 to 12 carbon atoms, or an unsaturated hydrocarbon group having 2 to 12 carbon atoms, and the saturated hydrocarbon group and the unsaturated hydrocarbon group may also have at least one selected from a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, and a halogen atom; however, when m is 1, R 2 and R 3 When one or both of them are hydrogen atoms and m is 2, 3 or 4, multiple R 2 and R 3 At least one of them is a hydrogen atom.

[0038] 3. The positive resist material according to 1 or 2, wherein the repeating unit b comprises at least one selected from the group consisting of a repeating unit b1 represented by the following formula (b1) and a repeating unit b2 represented by the following formula (b2);

[0039]

[0040] In the formula, R A are each independently a hydrogen atom or a methyl group;

[0041] Y 1 is a single bond, a phenylene group or a naphthylene group, or a linking group having 1 to 12 carbon atoms and comprising at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, the naphthylene group, and the linking group may also have at least one selected from a halogen atom, a nitro group, a hydroxyl group, a saturated hydrocarbonoxy group having 1 to 8 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 8 carbon atoms, and a saturated hydrocarbonoxycarbonyloxy group having 2 to 8 carbon atoms;

[0042] Y 2is a single bond, an ester bond or an amide bond;

[0043] Y 3 is a single bond, an ether bond or an ester bond;

[0044] R 11 and R 12 It is an acid-labile group;

[0045] R 13 is a fluorine atom, a trifluoromethyl group, a cyano group, or an alkyl group having 1 to 6 carbon atoms;

[0046] R 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of the -CH2- of the alkanediyl group may be substituted with an ether bond or an ester bond.

[0047] a is 1 or 2; b is an integer from 0 to 4; but 1≤a+b≤5.

[0048] 4. The positive resist material according to any one of 1 to 3, wherein the repeating unit c comprises at least one selected from the repeating units represented by the following formulae (c1) to (c5);

[0049]

[0050] In the formula, R A are each independently a hydrogen atom or a methyl group;

[0051] R B Each independently is a hydrogen atom or 6 Bonding to form a ring is also possible;

[0052] Z 1 is a single bond, an aliphatic alkylene 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 groups, or -OZ 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -;Z 11 It is an aliphatic alkylene 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 them; and it may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group;

[0053] Z 2 is a single bond or an ester bond;

[0054] Z 3 is a single bond, -Z 31 -C(=O)-O- or -Z 31 -O-;Z 31It is a carbonyl group having 1 to 12 carbon atoms, a phenylene group, or a group having 7 to 18 carbon atoms obtained by combining them; it may also contain a carbonyl group, a nitro group, a cyano group, an ester bond, an ether bond, a carbamate bond, a fluorine atom, an iodine atom, or a bromine atom;

[0055] Z 4 is a single bond, methylene or ethylene;

[0056] Z 5 is a single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OZ 51 -、-C(=O)-OZ 51 -or-C(=O)-NH-Z 51 -;Z 51 It is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a methylphenylene group, a dimethylphenylene group, a fluorinated phenylene group or a phenylene group substituted with a trifluoromethyl group, and may also contain a carbonyl group, an ester bond, an ether bond, a hydroxyl group or a halogen atom;

[0057] Z 6 is a single bond, a phenylene ring, a naphthylene ring, an ester bond, or an amide bond;

[0058] Z 7A is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom;

[0059] Z 7B is a monovalent organic group having 1 to 10 carbon atoms, and may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom and a sulfur atom;

[0060] Z 8 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms;

[0061] Z 9 is a trivalent organic group having 1 to 12 carbon atoms, and may have at least one atom selected from an oxygen atom, a nitrogen atom and a sulfur atom;

[0062] R 1 ~Rf 4 Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group; and Rf 1 and Rf 2 They can also combine to form a carbonyl group;

[0063] R 21 and R 22 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom;

[0064] R23 is a saturated hydrocarbon 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;

[0065] R is a (d+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms;

[0066] d is an integer from 0 to 5;

[0067] X - It is a non-nucleophilic counter ion;

[0068] M + It is a sulfonium cation or an iodonium cation.

[0069] 5. The positive resist material according to 4, wherein Z 3 , Z 7A , Z 7B or M + The iodine atom is one containing at least one iodine atom.

[0070] 6. A positive resist material as described in any one of 1 to 5, wherein the base polymer further comprises a repeating unit d having an adhesion group selected from a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether bond, an ester bond, a sulfonate bond, a cyano group, an amide group, -OC(=O)-S- and -OC(=O)-NH-.

[0071] 7. The positive resist material according to any one of 1 to 6, further comprising an acid generator.

[0072] 8. The positive resist material according to any one of 1 to 7, further comprising an organic solvent.

[0073] 9. The positive resist material according to any one of 1 to 8, further comprising a quencher.

[0074] 10. The positive resist material according to any one of 1 to 9, further comprising a surfactant.

[0075] 11. A pattern forming method comprising the following steps:

[0076] forming a resist film on a substrate using the positive resist material according to any one of 1 to 10;

[0077] exposing the resist film to high energy radiation;

[0078] The exposed resist film is developed using a developer.

[0079] 12. The pattern forming method according to 11, wherein the high-energy ray is i-ray, KrF excimer laser, ArF excimer laser, electron beam (EB) or EUV with a wavelength of 3 to 15 nm.

[0080] [Effects of the Invention]

[0081] The positive resist material of the present invention has good alkali solubility in the exposed part and can improve the decomposition efficiency of the acid generator, so it has a high effect of inhibiting acid diffusion, high sensitivity, and high resolution. The pattern shape after exposure is good, the LWR is small, the CDU is excellent, there is no tailing or residue in the spacer part, and there is no microbridge between the connecting patterns. The carboxyl group and phenolic hydroxyl group of salicylic acid form a ring with hydrogen bonding properties, which has the effect of reducing the swelling of the carboxyl group in the alkaline developer. This effect is the same even if the carboxyl group or the phenolic hydroxyl group is substituted. The polymer obtained by copolymerizing the polymerizable salicylic acid has low swelling and improved alkali dissolution rate, so the above-mentioned good characteristics can be obtained. Therefore, because it has these excellent characteristics, it is extremely practical, especially as a fine pattern forming material for photomasks for ultra-LSI manufacturing or EB drawing, and a pattern forming material for EB or EUV exposure. In addition to photolithography in semiconductor circuit formation, the positive resist material of the present invention can also be used in the formation of mask circuit patterns, micromachines, and thin film head circuit formation. DETAILED DESCRIPTION

[0082] [Positive resist material]

[0083] The positive resist material of the present invention comprises a base polymer, which contains: a repeating unit a having a substituted or unsubstituted carboxyl group and a substituted or unsubstituted phenolic hydroxyl group, but the repeating unit a has at least one selected from an unsubstituted carboxyl group and an unsubstituted phenolic hydroxyl group, a repeating unit b having an acid-labile group, and a repeating unit c having a sulfonium salt or iodonium salt structure of a sulfonic acid bonded to the polymer main chain.

[0084] [Base polymer]

[0085] The repeating unit a is preferably represented by the following formula (a).

[0086]

[0087] In formula (a), k is 0 or 1. m is an integer of 1 to 4, preferably 1, 2 or 3, more preferably 1 or 2, and even more preferably 1. n is an integer of 0 to 4, preferably 0 or 1, and even more preferably 0.

[0088] In formula (a), R A A hydrogen atom or a methyl group.

[0089] In formula (a), X 1 It is a single bond or an ester bond.

[0090] In formula (a), X 2 It is a single bond, a saturated alkylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group. The saturated alkylene group may be straight chain, branched or cyclic. Specific examples thereof include alkylene groups having 1 to 10 carbon atoms, such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, and cyclic saturated alkylene groups having 3 to 10 carbon atoms, such as cyclopentanediyl, cyclohexanediyl, norbornanediyl and adamantanediyl.

[0091] In formula (a), X 3 It is a single bond, an ester bond, an ether bond or a carbonyl group.

[0092] In formula (a), R 1 It is an alkyl group having 1 to 4 carbon atoms or a halogen atom. Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl.

[0093] In formula (a), R 2 is a hydrogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 7 carbon atoms, or a saturated hydrocarbon oxycarbonyl group having 2 to 7 carbon atoms. The saturated hydrocarbon group, the saturated hydrocarbon carbonyl group, and the saturated hydrocarbon oxycarbonyl group may be straight chain, branched, or cyclic. Specific examples thereof 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, tert-pentyl, neopentyl, and n-hexyl; cyclic saturated hydrocarbon groups having 3 to 6 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopentyl, and cyclohexyl; and groups obtained by combining these. When m is 2, 3, or 4, each R 2 They can be the same or different.

[0094] In formula (a), R 3is a hydrogen atom, a saturated hydrocarbon group having 1 to 12 carbon atoms, or an unsaturated hydrocarbon group having 2 to 12 carbon atoms, and the saturated hydrocarbon group and the unsaturated hydrocarbon group may also have at least one selected from a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, and a halogen atom. The saturated hydrocarbon group may be linear, branched, or cyclic. Specific examples thereof 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, tert-pentyl, neopentyl, and n-hexyl; cyclic saturated hydrocarbon groups having 3 to 6 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopentyl, and cyclohexyl; and groups obtained by combining these. The unsaturated hydrocarbon group may be straight-chain, branched or cyclic. Specific examples thereof include alkenyl groups having 2 to 7 carbon atoms, such as vinyl, 1-propenyl, 2-propenyl, isopropenyl, etc.; alkynyl groups having 2 to 7 carbon atoms, such as ethynyl, 1-propynyl, 2-propynyl, etc.; and the like. In addition, the saturated hydrocarbon group and the unsaturated hydrocarbon group may be substituted by a hydroxyl group, an alkoxy group or a halogen atom. Specific examples of such groups include monofluoroethyl, difluoroethyl, trifluoroethyl, hexafluoroisopropyl, monoiodoethyl, monoiodopropyl, etc.

[0095] However, when m is 1, R 2 and R 3 When one or both of them are hydrogen atoms and m is 2, 3 or 4, multiple R 2 and R 3 At least one of them is a hydrogen atom.

[0096] Specific examples of monomers providing repeating unit a include those shown below. However, they are not limited to these. In the following formula, R A Same as above.

[0097]

[0098]

[0099]

[0100]

[0101] The repeating unit b is used to improve the solubility contrast. The repeating unit b preferably includes at least one selected from the repeating unit b1 represented by the following formula (b1) and the repeating unit b2 represented by the following formula (b2).

[0102]

[0103] In formula (b1) and (b2), R A Each is independently a hydrogen atom or a methyl group.

[0104] Y 1is a single bond, a phenylene group or a naphthylene group, or a linking group having 1 to 12 carbon atoms and including at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, the naphthylene group, and the linking group may also have at least one selected from a halogen atom, a nitro group, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms, and a saturated hydrocarbon oxycarbonyloxy group having 2 to 8 carbon atoms. 2 is a single bond, an ester bond or an amide bond. 3 is a single bond, an ether bond or an ester bond. 11 and R 12 R is an acid-labile group. 13 R is a fluorine atom, a trifluoromethyl group, a cyano group, or an alkyl group having 1 to 6 carbon atoms. 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of -CH2- in the alkanediyl group may be substituted with an ether bond or an ester bond. a is 1 or 2. b is an integer from 0 to 4. However, 1≤a+b≤5.

[0105] The monomers providing the repeating unit b1 include the following. However, they are not limited to these. In the following formula, R A and R 11 Same as above.

[0106]

[0107]

[0108] The monomers providing the repeating unit b2 include the following monomers. However, they are not limited to these monomers. A and R 12 Same as above.

[0109]

[0110] Just R 11 or R 12 There are various options for the acid-labile group represented by , and examples thereof include those represented by the following formulae (AL-1) to (AL-3).

[0111]

[0112] In the formula, the dotted lines are atomic bonds.

[0113] In formula (AL-1), c is an integer of 0 to 6. L1 A tertiary hydrocarbon group having 4 to 20 carbon atoms, preferably 4 to 15 carbon atoms, a trihydrocarbylsilyl group in which each hydrocarbon group is a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon group having 4 to 20 carbon atoms containing a carbonyl group, an ether bond or an ester bond, or a group represented by the formula (AL-3). In addition, the tertiary hydrocarbon group refers to a group obtained by removing a hydrogen atom from a tertiary carbon atom of a hydrocarbon.

[0114] R L1 The tertiary hydrocarbon group represented by may be saturated or unsaturated, branched or cyclic. Specific examples thereof include tert-butyl, tert-amyl, 1,1-diethylpropyl, 1-ethylcyclopentyl, 1-butylcyclopentyl, 1-ethylcyclohexyl, 1-butylcyclohexyl, 1-ethyl-2-cyclopentenyl, 1-ethyl-2-cyclohexenyl, 2-methyl-2-adamantyl, etc. As for the aforementioned trihydrocarbylsilyl, examples include trimethylsilyl, triethylsilyl, dimethyl-tert-butylsilyl, etc. The saturated hydrocarbon group containing a carbonyl group, an ether bond or an ester bond may be straight chain, branched or cyclic, but a cyclic one is more preferable. Specific examples thereof include 3-oxocyclohexyl, 4-methyl-2-oxooxan-4-yl, 5-methyl-2-oxotetrahydrofuran-5-yl, 2-tetrahydropyranyl and 2-tetrahydrofuranyl.

[0115] Examples of the acid-labile group represented by the formula (AL-1) include tert-butoxycarbonyl, tert-butoxycarbonylmethyl, tert-amyloxycarbonyl, tert-amyloxycarbonylmethyl, 1,1-diethylpropyloxycarbonyl, 1,1-diethylpropyloxycarbonylmethyl, 1-ethylcyclopentyloxycarbonyl, 1-ethylcyclopentyloxycarbonylmethyl, 1-ethyl-2-cyclopentenyloxycarbonyl, 1-ethyl-2-cyclopentenyloxycarbonylmethyl, 1-ethoxyethoxycarbonylmethyl, 2-tetrahydropyranyloxycarbonylmethyl, and 2-tetrahydrofuranyloxycarbonylmethyl.

[0116] Next, examples of the acid-labile group represented by the formula (AL-1) include groups represented by the following formulae (AL-1)-1 to (AL-1)-10.

[0117]

[0118] In the formula, the dotted lines are atomic bonds.

[0119] In the formulas (AL-1)-1 to (AL-1)-10, c is the same as described above. L8 Each R is independently a saturated hydrocarbon 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 hydrocarbon group having 1 to 10 carbon atoms. L10 It is a saturated hydrocarbon group having 2 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. The saturated hydrocarbon group may be linear, branched or cyclic.

[0120] In formula (AL-2), R L2 and R L3Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The saturated hydrocarbon group may be linear, branched or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclopentyl, cyclohexyl, 2-ethylhexyl and n-octyl.

[0121] In formula (AL-2), R L4 The hydrocarbon group may contain heteroatoms and has 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Examples of the hydrocarbon group include saturated hydrocarbon groups having 1 to 18 carbon atoms, and some of the hydrogen atoms may be substituted by hydroxyl, alkoxy, oxo, amino, alkylamino, etc. Examples of such substituted saturated hydrocarbon groups include those shown below.

[0122]

[0123] In the formula, the dotted lines are atomic bonds.

[0124] R L2 With R L3 , R L2 With R L4 , or R L3 With R L4 They may also be bonded to each other to form a ring with the carbon atom or the carbon atom and oxygen atom to which they are bonded. In this case, R L2 and R L3 , R L2 and R L4 , or R L3 and R L4 Each independently represents an alkanediyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The carbon number of the ring formed by bonding these groups is preferably 3 to 10, more preferably 4 to 10 carbon atoms.

[0125] Among the acid-labile groups represented by formula (AL-2), examples of linear or branched ones include those represented by the following formulae (AL-2)-1 to (AL-2)-69, but are not limited thereto. In the following formulae, the dotted lines represent atomic bonds.

[0126]

[0127]

[0128]

[0129]

[0130]

[0131] Among the acid-labile groups represented by the formula (AL-2), examples of cyclic groups include tetrahydrofuran-2-yl, 2-methyltetrahydrofuran-2-yl, tetrahydropyran-2-yl, and 2-methyltetrahydropyran-2-yl.

[0132] Examples of the acid-labile group include groups represented by the following formula (AL-2a) or (AL-2b): The base polymer may be crosslinked intermolecularly or intramolecularly by the acid-labile group.

[0133]

[0134] In the formula, the dotted lines are atomic bonds.

[0135] In formula (AL-2a) or (AL-2b), R L11 and R L12 Each independently represents a hydrogen atom or a saturated hydrocarbon group having 1 to 8 carbon atoms. The saturated hydrocarbon group may be linear, branched or cyclic. L11 With R L12 They can also bond to each other and form a ring together with the carbon atoms to which they are bonded. In this case, R L11 and R L12 Each R is independently an alkanediyl group having 1 to 8 carbon atoms. L13 Each is independently a saturated alkylene group having 1 to 10 carbon atoms. The saturated alkylene group may be linear, branched or cyclic. d and e are each independently an integer of 0 to 10, preferably an integer of 0 to 5, and f is an integer of 1 to 7, preferably an integer of 1 to 3.

[0136] In formula (AL-2a) or (AL-2b), L A is an aliphatic saturated hydrocarbon group having 1 to 50 carbon atoms and having a valence of (f+1) , an alicyclic saturated hydrocarbon group having 3 to 50 carbon atoms and having a valence of (f+1) , an aromatic hydrocarbon group having 6 to 50 carbon atoms and having a valence of (f+1) , or a heterocyclic group having 3 to 50 carbon atoms and having a valence of (f+1) . In addition, part of the -CH2- in these groups may be substituted by a group containing a heteroatom, and part of the hydrogen atoms in these groups may be substituted by a hydroxyl group, a carboxyl group, an acyl group or a fluorine atom. A Preferably, it is a saturated hydrocarbon group such as a saturated hydrocarbon group having 1 to 20 carbon atoms, a trivalent saturated hydrocarbon group, a tetravalent saturated hydrocarbon group, or an arylene group having 6 to 30 carbon atoms. The saturated hydrocarbon group may be linear, branched, or cyclic. B It is -C(=O)-O-, -NH-C(=O)-O- or -NH-C(=O)-NH-.

[0137] Examples of the cross-linked acetal group represented by the formula (AL-2a) or (AL-2b) include groups represented by the following formulae (AL-2)-70 to (AL-2)-77.

[0138]

[0139]

[0140] In the formula, the dotted lines are atomic bonds.

[0141] In formula (AL-3), R L5 , R L6 and R L7 Each is independently a hydrocarbon group having 1 to 20 carbon atoms, and may also contain heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and fluorine atoms. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 20 carbon atoms, cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, cyclic unsaturated hydrocarbon groups having 3 to 20 carbon atoms, and aryl groups having 6 to 10 carbon atoms. In addition, R L5 With R L6 , R L5 With R L7 , or R L6 With R L7 They may be bonded to each other to form an alicyclic ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded.

[0142] Examples of the group represented by the formula (AL-3) include tert-butyl, 1,1-diethylpropyl, 1-ethylnorbornyl, 1-methylcyclopentyl, 1-ethylcyclopentyl, 1-isopropylcyclopentyl, 1-methylcyclohexyl, 2-(2-methyl)adamantyl, 2-(2-ethyl)adamantyl, and tert-pentyl.

[0143] Examples of the group represented by the formula (AL-3) include groups represented by the following formulae (AL-3)-1 to (AL-3)-19.

[0144]

[0145] In the formula, the dotted lines are atomic bonds.

[0146] In formula (AL-3)-1~(AL-3)-19, R L14 Each R is independently a hydrogen atom, a saturated hydrocarbon group having 1 to 8 carbon atoms, or an aryl group having 6 to 20 carbon atoms. L15 and R L17 Each R is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 20 carbon atoms. L16 is an aryl group having 6 to 20 carbon atoms. The saturated hydrocarbon group may be linear, branched or cyclic. The aryl group is preferably a phenyl group. F is a fluorine atom or a trifluoromethyl group. g is an integer of 1-5.

[0147] Next, examples of the acid-labile group include groups represented by the following formula (AL-3)-20 or (AL-3)-21. The acid-labile group can also crosslink the polymer intramolecularly or intermolecularly.

[0148]

[0149] In the formula, the dotted lines are atomic bonds.

[0150] In formula (AL-3)-20 and (AL-3)-21, R L14 Same as above. L18 It is a saturated alkylene group with a valence of (h+1) and a carbon number of 1 to 20 or an arylene group with a valence of (h+1) and a carbon number of 6 to 20, and may contain heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. The saturated alkylene group may be linear, branched, or cyclic. h is an integer of 1 to 3.

[0151] Examples of the monomer providing a repeating unit containing an acid-labile group represented by the formula (AL-3) include (meth)acrylates containing an exo-stereoisomer structure represented by the following formula (AL-3)-22.

[0152]

[0153] In formula (AL-3)-22, R A Same as above. Lc1 is a saturated hydrocarbon group having 1 to 8 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms. The saturated hydrocarbon group may be linear, branched or cyclic. Lc2 ~R Lc11 Each is independently a hydrogen atom or a hydrocarbon group having 1 to 15 carbon atoms which may contain a hetero atom. Examples of the hetero atom include an oxygen atom. Examples of the hydrocarbon group include an alkyl group having 1 to 15 carbon atoms and an aryl group having 6 to 15 carbon atoms. Lc2 With R Lc3 , R Lc4 With R Lc6 , R Lc4 With R Lc7 , R Lc5 With R Lc7 , R Lc5 With R Lc11 , R Lc6 With R Lc 10 , R Lc8 With R Lc9 , or R Lc9 With R Lc10 , may also be bonded to each other and form a ring together with the carbon atoms to which they are bonded. In this case, the group involved in the bond is an alkylene group having 1 to 15 carbon atoms and may also contain heteroatoms.Lc2 With R Lc11 , R Lc8 With R Lc11 , or R Lc4 With R Lc6 , and can also form double bonds without spacing between adjacent carbon atoms. In addition, this formula also represents mirror images.

[0154] Here, as for the monomer represented by formula (AL-3)-22, examples thereof include those described in Japanese Patent Publication No. 2000-327633. Specifically, examples thereof include those shown below. However, the present invention is not limited to these. In the following formula, R A Same as above.

[0155]

[0156] Examples of the monomer providing a repeating unit containing an acid-labile group represented by formula (AL-3) include (meth)acrylates containing a furandiyl group, a tetrahydrofurandiyl group or an oxanorbornanediyl group represented by the following formula (AL-3)-23.

[0157]

[0158]

[0159] In formula (AL-3)-23, R A Same as above. Lc12 and R Lc13 Each R is independently a hydrocarbon group having 1 to 10 carbon atoms. Lc12 With R Lc13 They may also bond to each other and form an aliphatic ring together with the carbon atoms to which they are bonded. Lc14 R is furandiyl, tetrahydrofurandiyl or oxanorbornanediyl. Lc15 It is a hydrocarbon group having 1 to 10 carbon atoms which may contain a hydrogen atom or a hetero atom. The hydrocarbon group may be linear, branched or cyclic. Specific examples thereof include saturated hydrocarbon groups having 1 to 10 carbon atoms.

[0160] The monomers represented by formula (AL-3)-23 include the following. However, they are not limited to these. In the following formula, R A As mentioned above, Ac is acetyl and Me is methyl.

[0161] [Chemistry 30]

[0162]

[0163] The repeating unit c is a repeating unit that functions as an acid generator. The repeating unit c is preferably a repeating unit c containing at least one acid generator selected from the repeating units represented by the following formulae (c1) to (c5).

[0164]

[0165] In formulas (c1) to (c3), R A Each is independently a hydrogen atom or a methyl group.

[0166] In formula (c1), Z 1 is a single bond, an aliphatic alkylene 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 groups, or -OZ 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -.Z 11 It is an aliphatic alkylene 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 them, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0167] In formula (c1), R 21 and R 22 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include those in the description of formulas (M1) and (M2) described below. 41 ~R 45 The hydrocarbon groups having 1 to 20 carbon atoms shown in the examples are the same as those shown in the examples.

[0168] The cation of the monomer providing the repeating unit c1 may be exemplified by the following. However, it is not limited to these. In the following formula, R A Same as above.

[0169]

[0170] In formula (c1), X -It is a non-nucleophilic counter ion. Examples of the non-nucleophilic counter ions include halide ions such as chloride ion and bromide ion; fluoroalkylsulfonate ions such as trifluoromethanesulfonate ion, 1,1,1-trifluoroethanesulfonate ion and nonafluorobutanesulfonate ion; arylsulfonate ions such as toluenesulfonate ion, benzenesulfonate ion, 4-fluorobenzenesulfonate ion and 1,2,3,4,5-pentafluorobenzenesulfonate ion; alkylsulfonate ions such as methanesulfonate ion and butanesulfonate ion; imide ions such as bis(trifluoromethylsulfonyl)imide ion, bis(perfluoroethylsulfonyl)imide ion and bis(perfluorobutylsulfonyl)imide ion; methide ions such as tris(trifluoromethylsulfonyl)methide ion and tris(perfluoroethylsulfonyl)methide ion.

[0171] As for the aforementioned non-nucleophilic relative ions, there can also be listed sulfonate ions represented by the following formula (c1-1) in which the α-position is substituted with a fluorine atom, sulfonate ions represented by the following formula (c1-2) in which the α-position is substituted with a fluorine atom and the β-position is substituted with a trifluoromethyl group, etc.

[0172]

[0173] In formula (c1-1), R 31 It is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may contain an ether bond, an ester bond, a carbonyl group, a lactone ring or a fluorine atom. The hydrocarbon group may be saturated or unsaturated, and may be straight-chain, branched or cyclic.

[0174] In formula (c1-2), R 32 It is a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or a hydrocarbon carbonyl group having 2 to 30 carbon atoms. The hydrocarbon group and hydrocarbon carbonyl group may contain an ether bond, an ester bond, a carbonyl group, or a lactone ring. The hydrocarbon group and hydrocarbon carbonyl group may be saturated or unsaturated, and may be straight-chain, branched, or cyclic.

[0175] As the non-nucleophilic counter ion, an anion including an aromatic ring substituted with a bromine atom or an iodine atom represented by the following formula (c1-3) can also be used.

[0176]

[0177] In formula (c1-3), 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, more preferably 2 or 3. r is preferably an integer satisfying 0≤r≤2.

[0178] In formula (c1-3), X BI is an iodine atom or a bromine atom, and when p and / or q is 2 or more, they may be the same as or different from each other.

[0179] In formula (c1-3), L 1 It is a single bond, an ether bond or an ester bond, or a saturated alkylene group having 1 to 6 carbon atoms which may contain an ether bond or an ester bond. The saturated alkylene group may be linear, branched or cyclic.

[0180] In formula (c1-3), L 2 When p is 1, it is a single bond or a divalent linking group having 1 to 20 carbon atoms. When p is 2 or 3, it is a (p+1)-valent linking group having 1 to 20 carbon atoms. The linking group may contain an oxygen atom, a sulfur atom or a nitrogen atom.

[0181] In formula (c1-3), R 33 is a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a bromine atom or an amino group, or a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbonoxy group having 1 to 20 carbon atoms, a hydrocarboncarbonyl group having 2 to 20 carbon atoms, a hydrocarbonoxycarbonyl group having 2 to 20 carbon atoms, a hydrocarboncarbonyloxy group having 2 to 20 carbon atoms or a hydrocarbonsulfonyloxy group having 1 to 20 carbon atoms which may contain a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, an amino group or an ether bond, or -N(R 33A )(R 33B )、-N(R 33C )-C(=O)-R 33D or -N(R 33C )-C(=O)-OR 33D . R 33A and R 33B Each R is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. 33C R is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, and may contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyloxy group having 2 to 6 carbon atoms. 33D It is an aliphatic hydrocarbon 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 also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyloxy group having 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. The aforementioned hydrocarbon group, hydrocarbonoxy group, hydrocarbonoxycarbonyl group, hydrocarboncarbonyl group, hydrocarboncarbonyloxy group, and hydrocarbonsulfonyloxy group may be straight-chain, branched, or cyclic. When p and / or r are 2 or more, each R 33 They can be the same or different.

[0182] Among these, R 33 For hydroxyl, -N(R 33C )-C(=O)-R 33D 、-N(R 33C )-C(=O)-OR 33D , fluorine atom, chlorine atom, bromine atom, methyl group, methoxy group and the like are preferred.

[0183] In formula (c1-3), Rf 11 ~Rf 14 Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group. 11 With Rf 12 They may also be combined to form a carbonyl group. In particular, Rf 13 and Rf 14 Preferably, they are all fluorine atoms.

[0184] Examples of the anion represented by the formula (c1-3) include those shown below, but are not limited to these.

[0185] In addition, in the following formula, X BI Same as above.

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201]

[0202]

[0203]

[0204]

[0205]

[0206]

[0207]

[0208] In formula (c2), Z 2 is a single bond or an ester bond. 3 is a single bond, -Z 31 -C(=O)-O- or -Z 31 -O-.Z 31 Z is a C1-12 alkylene group, a phenylene group, or a group having C7-18 obtained by combining these groups, and may contain a carbonyl group, a nitro group, a cyano group, an ester bond, an ether bond, a carbamate bond, a fluorine atom, an iodine atom, or a bromine atom. 4 It is a single bond, methylene or ethylene.

[0209] In formula (c2), Rf 1 ~Rf 4 Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group, and at least one of them is a fluorine atom or a trifluoromethyl group. 1 and Rf 2 They may also combine to form a carbonyl group.

[0210] The anion of the monomer providing the repeating unit c2 may be exemplified by the following. However, it is not limited to these. In the following formula, R A Same as above.

[0212]

[0213]

[0214]

[0215]

[0216]

[0217]

[0218]

[0219] In formula (c3), Z 5 is a single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OZ 51 -、-C(=O)-OZ51 -or-C(=O)-NH-Z 51 -.Z 51 It is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a methylphenylene group, a dimethylphenylene 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 hydroxyl group or a halogen atom.

[0220] The anion of the monomer providing the repeating unit c3 may be exemplified by the following. However, it is not limited to these. In the following formula, R A Same as above.

[0221]

[0222]

[0223] In formula (c4) and (c5), R A Each is independently a hydrogen atom or a methyl group. B are independently a hydrogen atom, or may be 6 bond to form a ring.

[0224] In formula (c4) and (c5), Z 6 It is a single bond, a phenylene group, a naphthylene ring, an ester bond or an amide bond.

[0225] In formula (c4), Z 7A It is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0226] Z 7AThe divalent organic group represented by may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include a hydrocarbon group having 1 to 24 carbon atoms in which a part or all of the hydrogen atoms are replaced by iodine atoms or bromine atoms. Examples of the alkylene group having 1 to 24 carbon atoms include alkylene groups such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecane-1,17-diyl, octadecane-1,18-diyl, nonadecane-1,19-diyl and eicosane-1,20-diyl; and cyclopentane Z is a cyclic saturated alkylene group such as cyclopentanediyl, methylcyclopentanediyl, dimethylcyclopentanediyl, trimethylcyclopentanediyl, tetramethylcyclopentanediyl, cyclohexanediyl, methylcyclohexanediyl, dimethylcyclohexanediyl, trimethylcyclohexanediyl, tetramethylcyclohexanediyl, norbornanediyl, and adamantanediyl; an arylene group 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 a group obtained by combining these. 7A Some or all of the hydrogen atoms in Z may be substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom. 7A A portion of -CH2- may be substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, and as a result, may contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a carbamate bond, a urea bond, or the like.

[0227] In formula (c5), Z 7B It is a monovalent organic group having 1 to 10 carbon atoms, and may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0228] Z 7BThe monovalent organic group represented by may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include hydrocarbon groups having 1 to 10 carbon atoms in which a part or all of the hydrogen atoms are replaced by iodine atoms or bromine atoms. Examples of the hydrocarbon 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; cyclic saturated hydrocarbon groups having 3 to 10 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, norbornyl, cyclopropylmethyl, cyclopropylethyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl, cyclohexylethyl, methylcyclopropyl, methylcyclobutyl, methylcyclopentyl, methylcyclohexyl, ethylcyclopropyl, ethylcyclobutyl, ethylcyclopentyl, and ethylcyclohexyl; and vinyl, 1-propenyl, 2- Alkenyl groups having 2 to 10 carbon atoms, such as propenyl, butenyl, pentenyl, hexenyl, heptenyl, nonenyl, and decenyl; alkynyl groups having 2 to 10 carbon atoms, such as ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, and decenyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 10 carbon atoms, such as cyclopentenyl, cyclohexenyl, methylcyclopentenyl, methylcyclohexenyl, ethylcyclopentenyl, ethylcyclohexenyl, and norbornyl; aryl groups having 6 to 10 carbon atoms, such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, and naphthyl; aralkyl groups having 7 to 10 carbon atoms, such as benzyl, phenethyl, phenylpropyl, and phenylbutyl; and groups obtained by combining these. In addition, Z 7B Some or all of the hydrogen atoms in Z may be substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom. 7B A portion of -CH2- may be substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, and as a result, may contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a carbamate bond, a urea bond, or the like.

[0229] In formula (c4) and (c5), Z 8 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms.

[0230] In formula (c5), Z 9 It is a trivalent organic group having 1 to 12 carbon atoms, and may have at least one atom selected from an oxygen atom, a nitrogen atom, and a sulfur atom. 9The trivalent organic group represented by may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples thereof include groups obtained by removing one hydrogen atom from an alkylene group having 1 to 12 carbon atoms. Examples of the aforementioned alkylene group having 1 to 12 carbon atoms include those having 1 to 12 carbon atoms among the aforementioned alkylene groups having 1 to 24 carbon atoms. 9 Some or all of the hydrogen atoms in Z may be substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom. 9 A portion of -CH2- may be substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, and as a result, may contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a carbamate bond, a urea bond, or the like.

[0231] In formula (c4) and (c5), R 23 It is a saturated hydrocarbon 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.

[0232] In formulae (c4) and (c5), R is a (d+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms. Specific examples of the (d+2)-valent aromatic hydrocarbon group include groups obtained by removing (d+2) hydrogen atoms from aromatic hydrocarbons such as benzene and naphthalene.

[0233] In formula (c4) and (c5), d is an integer of 0-5.

[0234] Specific examples of anions of repeating units c4 and c5 include those shown below. However, they are not limited to these. In the following formula, R A Same as above, X BI is an iodine atom or a bromine atom.

[0236]

[0237]

[0238]

[0239]

[0240]

[0241]

[0242]

[0243]

[0244]

[0245]

[0246]

[0247]

[0248]

[0249]

[0250]

[0251]

[0252]

[0253]

[0254]

[0255]

[0256]

[0257]

[0258]

[0259]

[0260]

[0261]

[0262]

[0263]

[0264]

[0265]

[0266]

[0267] In formulas (c2) to (c5), M + It is a sulfonium cation or an iodonium cation. The sulfonium cation is preferably represented by the following formula (M1), and the iodonium cation is preferably represented by the following formula (M2).

[0268]

[0269] In formula (M1) and (M2), R 41 ~R 45 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom.

[0270] Just R 41 ~R 45 Specific examples of the halogen atom represented by include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like.

[0271] R 41 ~R 45 The hydrocarbon group having 1 to 20 carbon atoms represented by may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecyl, octadecyl, nonadecyl, and eicosyl; cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, and adamantyl; and saturated hydrocarbon groups having 2 to 20 carbon atoms, such as vinyl, propenyl, butenyl, and hexenyl. 0; alkynyl having 2 to 20 carbon atoms, such as ethynyl, propynyl and butynyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 20 carbon atoms, such as cyclohexenyl and norbornyl; aryl groups having 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; aralkyl groups having 7 to 20 carbon atoms, such as benzyl and phenethyl; groups obtained by combining them, etc.

[0272] Furthermore, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of the -CH2- of the aforementioned hydrocarbon group may be substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom. As a result, the hydrocarbon group may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a thiol group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, and the like.

[0273] Again, R 41 and R 42 They may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, the ring is preferably in the structure shown below.

[0274]

[0275] In the formula, the dotted lines represent atomic bonds.

[0276] Just M + Specific examples of the sulfonium cation represented by include those shown below, but are not limited to these.

[0277]

[0278]

[0279]

[0280]

[0281]

[0282]

[0283]

[0284]

[0285]

[0286]

[0287]

[0288]

[0289]

[0290]

[0291]

[0292]

[0293]

[0294]

[0295]

[0296]

[0297]

[0298]

[0299]

[0300]

[0301]

[0302]

[0303] Just M + Specific examples of the iodonium cation represented by include those shown below, but are not limited to these.

[0305]

[0306] In the case of repeating unit c, it is repeating unit c2, c4 or c5, Z 3 , Z 7A , Z 7B or M + It is preferred that at least one iodine atom is contained.

[0307] The aforementioned base polymer may also further contain a repeating unit d having an adhesion group selected from a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether bond, an ester bond, a sulfonate bond, a cyano group, an amide group, -OC(=O)-S- and -OC(=O)-NH-.

[0308] Examples of the monomer that provides the repeating unit d include the following, but are not limited to these.

[0309] In addition, in the following formula, R A Same as above.

[0310]

[0311]

[0312]

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319] The aforementioned base polymer may also contain no amino group and contain a repeating unit e containing an iodine atom. Examples of the monomer that provides the repeating unit e are as shown below. However, it is not limited to these. In addition, in the following formula, R A Is the same as the aforementioned one.

[0321]

[0322]

[0323] The aforementioned base polymer may also contain a repeating unit f other than the aforementioned repeating units. Examples of the repeating unit e include those derived from styrene, vinylnaphthalene, indene, acenaphthene, coumarin, coumarone, etc.

[0324] In the aforementioned base polymer, the content ratios of the repeating units a, b1, b2, c1, c2, c3, c4, c5, d, e, and f are 0 < a ≤ 0.5, 0 ≤ b1 ≤ 0.8, 0 ≤ b2 ≤ 0.8, 0 < b1 + b2 ≤ 0.8, 0 ≤ c1 ≤ 0.5, 0 ≤ c2 ≤ 0.5, 0 ≤ c3 ≤ 0.5, 0 ≤ c4 ≤ 0.5, 0 ≤ c5 ≤ 0.5, 0 < c1 + c2 + c3 + c4 + c5 ≤ 0.5, 0 ≤ d ≤ 0.9, 0 ≤ e ≤ 0.5, and 0 ≤ f ≤ 0.5 are more ideal, 0.001 ≤ a ≤ 0.4, 0 ≤ b1 ≤ 0.75, 0 ≤ b2 ≤ 0.75, 0.1 ≤ b1 + b2 ≤ 0.8, 0 ≤ c1 ≤ 0.4, 0 ≤ c2 ≤ 0.4, 0 ≤ c3 ≤ 0.4, 0 ≤ c4 ≤ 0.4, 0 ≤ c5 ≤ 0.4, 0.01 ≤ c1 + c2 + c3 + c4 + c5 ≤ 0.4, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.4, and 0 ≤ f ≤ 0.4 are more ideal, 0.002 ≤ a ≤ 0.3, 0 ≤ b1 ≤ 0.7, 0 ≤ b2 ≤ 0.7, 0.2 ≤ b1 + b2 ≤ 0.7, 0 ≤ c1 ≤ 0.3, 0 ≤ c2 ≤ 0.3, 0 ≤ c3 ≤ 0.3, 0 ≤ c4 ≤ 0.3, 0 ≤ c5 ≤ 0.3, 0.02 ≤ c1 + c2 + c3 + c4 + c5 ≤ 0.3, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.3, and 0 ≤ f ≤ 0.3 are even more ideal. However, a + b1 + b2 + c1 + c2 + c3 + c4 + c5 + d + e + f = 1.0.

[0325] When synthesizing the aforementioned base polymer, for example, the monomers that provide the aforementioned repeating units can be added with a radical polymerization initiator in an organic solvent and heated to carry out polymerization.

[0326] As for the organic solvent used in the polymerization, toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, propylene glycol monomethyl ether, γ-butyrolactone and mixed solvents thereof can be cited. As for the polymerization initiator, 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2-azobis(2-methylpropionate), benzoyl peroxide, lauroyl peroxide and the like can be cited. The temperature during the polymerization is preferably 50 to 80°C. The reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours.

[0327] When a monomer containing a hydroxyl group is copolymerized, the hydroxyl group may be replaced with an acetal group such as ethoxyethoxy which is easily deprotected by an acid during the polymerization and then deprotected by a weak acid and water after the polymerization. Alternatively, the hydroxyl group may be replaced with an acetyl group, a formyl group, a pivaloyl group, etc. and then hydrolyzed with an alkali after the polymerization.

[0328] When copolymerizing hydroxystyrene and hydroxyvinylnaphthalene, acetoxystyrene and acetoxyvinylnaphthalene may be used instead of hydroxystyrene and hydroxyvinylnaphthalene, and after the polymerization, the acetoxy group may be deprotected by the aforementioned alkaline hydrolysis to form hydroxystyrene and hydroxyvinylnaphthalene.

[0329] As the base for alkaline hydrolysis, aqueous ammonia, triethylamine, etc. can be used. 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.

[0330] The base polymer preferably has a polystyrene-equivalent weight average molecular weight (Mw) of 1000 to 500000, more preferably 2000 to 30000, as measured by gel permeation chromatography (GPC) using THF as a solvent. When Mw falls within the above range, the heat resistance and solubility of the resist film in an alkaline developer are good.

[0331] Then, when the molecular weight distribution (Mw / Mn) of the base polymer is wide, there are low molecular weight and high molecular weight polymers, so there is a risk of foreign matter being found on the pattern after exposure and the shape of the pattern being deteriorated. As the pattern rules become finer, the influence of Mw and Mw / Mn tends to become greater, so in order to make the positive resist material that can be used ideally in the fine pattern size, the base polymer Mw / Mn is preferably 1.0 to 2.0, especially 1.0 to 1.5.

[0332] In order to obtain a narrowly dispersed polymer, in addition to general radical polymerization, living radical polymerization can also be used. Examples of living radical polymerization include living radical polymerization using nitroxide radicals (Nitroxide-Mediated Radical Polymerization: NMP), atom transfer radical polymerization (Atom Transfer Radical Polymerization: ATRP), and reversible addition-fragmentation chain transfer (Reversible Addition-Fragmentation Chain Transfer: RAFT) polymerization.

[0333] The base polymer may include two or more polymers having different composition ratios, Mw, and Mw / Mn. In addition, a polymer containing repeating unit a and a polymer not containing repeating unit a may be mixed.

[0334] [Organic solvents]

[0335] The positive resist material of the present invention may also contain an organic solvent. The aforementioned organic solvent is not particularly limited as long as it can dissolve the aforementioned components and the components described below. Specific examples of the aforementioned organic solvent include ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone described in paragraphs

[0144] to

[0145] of Japanese Patent Gazette No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; and propylene glycol. Ethers such as 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 mono-tert-butyl ether acetate; lactones such as γ-butyrolactone, etc.

[0336] In the positive 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.

[0337] [Quencher]

[0338] The positive resist material of the present invention may also contain a quencher. The quencher is a compound that can prevent the acid generated from the acid generator in the resist material from diffusing to the unexposed area by capturing the acid generated from the acid generator in the resist material.

[0339] As for the aforementioned quencher, known basic compounds can be cited. Specific examples of known basic compounds include primary, secondary, and tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having carboxyl groups, nitrogen-containing compounds having sulfonyl groups, nitrogen-containing compounds having hydroxyl groups, nitrogen-containing compounds having hydroxyphenyl groups, alcoholic nitrogen-containing compounds, amides, imides, and carbamates. In particular, primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Publication No. 2008-111103, especially amine compounds having hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, and sulfonate bonds, or compounds having carbamate bonds described in Japanese Patent Publication No. 3790649, are more desirable. By adding such basic compounds, for example, the diffusion rate of the acid in the resist film can be further suppressed and the shape can be corrected.

[0340] In addition, as for the above-mentioned quencher, there can be mentioned onium salts such as sulfonium salts, iodonium salts, and ammonium salts of sulfonic acids, carboxylic acids, or fluorinated alkoxides not fluorinated at the α-position as described in Japanese Patent Application Laid-Open No. 2008-158339. Sulfonic acids, imidic acids, or methylated acids fluorinated at the α-position are necessary to deprotect the acid-labile group of the carboxylate, and they release sulfonic acids, carboxylic acids, or fluorinated alcohols not fluorinated at the α-position due to salt exchange with the above-mentioned onium salts. Sulfonic acids, carboxylic acids, and fluorinated alcohols not fluorinated at the α-position do not cause deprotection reaction, and therefore also function as quenchers.

[0341] Specific examples of such quenchers include compounds represented by the following formula (1) (onium salt of sulfonic acid whose α-position is not fluorinated), compounds represented by the following formula (2) (onium salt of carboxylic acid), and compounds represented by the following formula (3) (onium salt of alkoxide).

[0342]

[0343] In formula (1), R 101 It is a hydrocarbon group having 1 to 40 carbon atoms which may contain a hydrogen atom or a hetero atom, but excludes a group in which the hydrogen atom bonded to the carbon atom at the α-position of the sulfonic acid group is substituted with a fluorine atom or a fluoroalkyl group.

[0344] R 101 The hydrocarbon group having 1 to 40 carbon atoms represented by may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 40 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, tricyclo[5.2.1.0 2,6] Cyclic saturated hydrocarbon groups having 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; alkenyl groups having 2 to 40 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 40 carbon atoms, such as cyclohexenyl; aryl groups having 6 to 40 carbon atoms, such as phenyl, naphthyl, alkylphenyl (2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butylphenyl, etc.), di- or trialkylphenyl (2,4-dimethylphenyl, 2,4,6-triisopropylphenyl, etc.), alkylnaphthyl (methylnaphthyl, ethylnaphthyl, etc.), dialkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); aralkyl groups having 7 to 40 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl, etc.

[0345] Furthermore, part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and part of the -CH2- of the aforementioned hydrocarbon group may be substituted by a group containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, and the like. Specific examples of the hydrocarbon group containing a heteroatom include heteroaryl groups such as thienyl; alkoxyphenyl groups such as 4-hydroxyphenyl, 4-methoxyphenyl, 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 4-tert-butoxyphenyl, and 3-tert-butoxyphenyl; alkoxynaphthyl groups such as methoxynaphthyl, ethoxynaphthyl, n-propoxynaphthyl, and n-butoxynaphthyl; dialkoxynaphthyl groups such as dimethoxynaphthyl and diethoxynaphthyl; aryloxyalkyl 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; and the like.

[0346] In formula (2), R 102 is a hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. 102 As specific examples of the hydrocarbon group represented by, for example, 101 The hydrocarbon groups represented by are the same as those exemplified. Other specific examples include fluorinated alkyl groups such as trifluoromethyl, trifluoroethyl, 2,2,2-trifluoro-1-methyl-1-hydroxyethyl, 2,2,2-trifluoro-1-(trifluoromethyl)-1-hydroxyethyl, and fluorinated aryl groups such as pentafluorophenyl and 4-trifluoromethylphenyl.

[0347] In formula (3), R 103 It is a saturated hydrocarbon group having 1 to 8 carbon atoms and having at least 3 fluorine atoms or an aryl group having 6 to 10 carbon atoms and having at least 3 fluorine atoms, and may contain a nitro group.

[0348] In formulas (1), (2) and (3), Mq + is an onium cation. As for the onium cation, it is preferably a sulfonium cation, an iodonium cation or an ammonium cation, and it is more preferably a sulfonium cation. As for the specific examples of the sulfonium cation, there can be cited the same as in the description of formula (a) with respect to M + The sulfonium cations exemplified are the same as those exemplified above.

[0349] As the quencher, a sulfonium salt of a carboxylic acid containing an iodinated benzene ring represented by the following formula (4) can also be preferably used.

[0350]

[0351] In formula (4), x is an integer of 1 to 5, y is an integer of 0 to 3, and z is an integer of 1 to 3.

[0352] In formula (4), R 111 is a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, a nitro group, a cyano group, or a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 6 carbon atoms, or a saturated hydrocarbon sulfonyloxy group having 1 to 4 carbon atoms, wherein a part 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 hydrocarbon group having 1 to 6 carbon atoms. 111B is a saturated hydrocarbon group having 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group having 2 to 8 carbon atoms. When y and / or z is 2 or more, each R 111 They can be the same or different from each other.

[0353] In formula (4), L 1 It 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 hydroxyl group, and a carboxyl group. The saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyloxy group, and saturated hydrocarbon sulfonyloxy group may be straight-chain, branched, or cyclic.

[0354] In formula (4), R 112 , R 113 and R 114 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: 41 ~R 45 The hydrocarbon groups exemplified are the same as those exemplified above.

[0355] Specific examples of the compound represented by formula (4) include those described in JP-A-2017-219836 and JP-A-2021-91666.

[0356] As other examples of the quencher, there can be mentioned a polymer quencher as described in Japanese Patent Application Laid-Open No. 2008-239918. The polymer quencher improves the rectangularity of the resist pattern by being aligned on the resist film surface. The polymer quencher also has the effect of preventing film loss of the pattern and rounding of the top of the pattern when applying a protective film for wet exposure.

[0357] Then, betaine-type sulfonium salts described in Japanese Patent No. 6848776 and Japanese Patent Application Laid-Open No. 2020-37544, methylated acids not containing fluorine atoms described in Japanese Patent Application Laid-Open No. 2020-55797, sulfonium salts of sulfonamides described in Japanese Patent 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.

[0358] When the positive resist material 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, based on 100 parts by mass of the base polymer. The quencher may be used alone or in combination of two or more.

[0359] [Other ingredients]

[0360] In addition to the above-mentioned components, an acid generator, a surfactant, a dissolution inhibitor, a water repellency improver, acetylene alcohols, etc. may be contained.

[0361] As for the aforementioned acid generator, there can be mentioned compounds (photoacid generators) that can generate acid by induction of active light or radiation. As for the composition of the photoacid generator, any compound that can generate acid due to high-energy ray irradiation can be used, but it is more desirable to be an acid generator that can generate sulfonic acid, imidic acid or methylated acid. As for specific examples of ideal photoacid generators, there can be mentioned sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate type acid generators, etc. Specific examples of the acid generator include those described in paragraphs

[0122] to

[0142] of Japanese Patent Application Laid-Open No. 2008-111103, Japanese Patent Application Laid-Open No. 2018-5224, Japanese Patent Application Laid-Open No. 2018-25789, Japanese Patent Application Laid-Open No. 2018-159744, Japanese Patent Application Laid-Open No. 2018-155908, etc. When the positive resist material of the present invention contains an acid generator, the content thereof is preferably 0 to 200 parts by mass, and preferably 0.1 to 100 parts by mass, relative to 100 parts by mass of the base polymer.

[0362] As specific examples of the above-mentioned surfactant, those described in paragraphs

[0165] to

[0166] of Japanese Patent Publication No. 2008-111103 can be cited. By adding a surfactant, the coating property of the resist material can be further improved or controlled. When the positive resist material of the present invention contains a surfactant, its content is preferably 0.0001 to 10 parts by mass relative to 100 parts by mass of the base polymer. The above-mentioned surfactant can be used alone or in combination of two or more.

[0363] The positive resist material of the present invention can make the difference in dissolution rate between the exposed part and the unexposed part larger by mixing a dissolution inhibitor, and can further improve the resolution. Specific examples of the above-mentioned dissolution inhibitor include compounds having a molecular weight of preferably 100 to 1000, more preferably 150 to 800, and in which the hydrogen atoms of the phenolic hydroxyl groups of a compound containing two or more phenolic hydroxyl groups in the molecule are replaced by acid-labile groups at a ratio of 0 to 100 mol% in total; or compounds in which the hydrogen atoms of the carboxyl groups of a compound containing a carboxyl group in the molecule are replaced by acid-labile groups at a ratio of 50 to 100 mol% in total. Specifically, compounds in which the hydrogen atoms of the hydroxyl groups and the carboxyl groups of bisphenol A, trisphenol, phenolphthalein, cresol novolac, naphthalenecarboxylic acid, adamantanecarboxylic acid, and bile acid are replaced by acid-labile groups, etc., for example, as described in paragraphs

[0155] to

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

[0364] When the positive resist material of the present invention contains the dissolution inhibitor, its content is preferably 0 to 50 parts by mass, more preferably 5 to 40 parts by mass, based on 100 parts by mass of the base polymer. The dissolution inhibitor may be used alone or in combination of two or more.

[0365] The aforementioned water repellency improver is a person who improves the water repellency of the surface of the resist film and can be used in immersion photolithography without using a topcoat. As for the aforementioned water repellency improver, it is more ideal to be a polymer containing a fluorinated alkyl group, a polymer containing a 1,1,1,3,3,3-hexafluoro-2-propanol residue of a specific structure, and the like, and it is more ideal to be exemplified in Japanese Patent Publication No. 2007-297590, Japanese Patent Publication No. 2008-111103, etc. The aforementioned water repellency improver must be dissolved in an alkaline developer or an organic solvent developer. The aforementioned specific water repellency improver having a 1,1,1,3,3,3-hexafluoro-2-propanol residue has good solubility in a developer. As for the water repellency improver, a polymer containing a repeating unit containing an amino group or an ammonium salt has a high effect of preventing the evaporation of the acid in the PEB and preventing the poor opening of the hole pattern after development. When the positive resist material of the present invention contains the water repellency improver, its content is preferably 0 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, based on 100 parts by mass of the base polymer. The water repellency improver may be used alone or in combination of two or more.

[0366] Specific examples of the acetylene alcohols include those described in paragraphs

[0179] to

[0182] of Japanese Patent Application Laid-Open No. 2008-122932. When the positive resist material of the present invention contains the acetylene alcohols, the content thereof is preferably 0 to 5 parts by mass relative to 100 parts by mass of the base polymer. The acetylene alcohols may be used alone or in combination of two or more.

[0367] [Pattern Formation Method]

[0368] When the positive resist material of the present invention is used in the manufacture of various integrated circuits, known photolithography techniques can be applied. For example, the pattern forming method includes the steps of forming a resist film on a substrate using the positive resist material, exposing the resist film to high-energy rays, and developing the exposed resist film using a developer.

[0369] First, the positive resist material of the present invention is applied to a substrate (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflective film, etc.) for integrated circuit manufacturing or a substrate (Cr, CrO, CrON, MoSi2, SiO2, etc.) for mask circuit manufacturing by a suitable coating method such as spin coating, roller coating, flow coating, dip coating, spray coating, blade coating, etc., with a coating film thickness of 0.01 to 2 μm. It is pre-baked on a hot plate at a more ideal temperature of 60 to 150° C. for 10 seconds to 30 minutes, and more preferably at a temperature of 80 to 120° C. for 30 seconds to 20 minutes to form a resist film.

[0370] Then, the resist film is exposed using high-energy radiation. Specific examples of the high-energy radiation include ultraviolet rays, far ultraviolet rays, EB, EUV with a wavelength of 3 to 15 nm, X-rays, soft X-rays, excimer lasers, gamma rays, synchrotron radiation, etc. When ultraviolet rays, far ultraviolet rays, EUV, X-rays, soft X-rays, excimer lasers, gamma rays, synchrotron radiation, etc. are used as the high-energy radiation, the exposure is preferably 1 to 200 mJ / cm directly or using a mask for forming a target pattern. 2 About 10 to 100 mJ / cm2 is more ideal 2 When EB is used as high energy radiation, the exposure dose is preferably 0.1 to 300 μC / cm 2 About 0.5 to 200 μC / cm2, more preferably 0.5 to 200 μC / cm2 2 In addition, the positive resist material of the present invention is particularly suitable for fine patterning by KrF excimer laser, ArF excimer laser, EB, EUV, X-ray, soft X-ray, gamma ray, synchrotron radiation, and is particularly suitable for fine patterning by EB or EUV among high-energy rays.

[0371] After the exposure, PEB may or may not be performed on a hot plate or in an oven at preferably 30 to 150° C. for 10 seconds to 30 minutes, more preferably 50 to 120° C. for 30 seconds to 20 minutes.

[0372] After exposure or PEB, the exposed resist film is developed using a developer of an alkaline aqueous solution of 0.1 to 10 mass %, preferably 2 to 5 mass %, such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, etc., for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, by a general method such as a dip method, a puddle method, or a spray method, whereby the portion irradiated with light is dissolved in the developer, while the unexposed portion is not dissolved, thereby forming a target pattern on the substrate.

[0373] A positive resist material containing a base polymer containing an acid-labile group may be used to obtain a negative pattern by developing with an organic solvent. Specific examples of the developer used at this time 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, amyl acetate, butyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonate, Ethyl crotonate, methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenylacetate, 2-phenylethyl acetate, etc. These organic solvents may be used alone or in combination of two or more.

[0374] When the development is terminated, rinsing is performed. As for the rinsing liquid, it is preferable to use a solvent that is miscible with the developer and does not dissolve the resist film. As for such a solvent, 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 can be preferably used.

[0375] Specific examples of the alcohol having 3 to 10 carbon atoms include n-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, tert-amyl alcohol, neopentyl alcohol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methyl-3-pentanol, cyclopentanol, 1-hexanol, 2-hexanol, 3-hexanol, 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, 1-octanol, etc.

[0376] 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.

[0377] Specific examples of the aforementioned 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 aforementioned alkenes having 6 to 12 carbon atoms include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, cyclooctene, etc. Specific examples of the aforementioned alkynes having 6 to 12 carbon atoms include hexyne, heptyne, octyne, etc.

[0378] Specific examples of the aromatic solvent include toluene, xylene, ethylbenzene, cumene, tert-butylbenzene, mesitylene, and the like.

[0379] By performing rinsing, the occurrence of collapse and defects of the resist pattern can be reduced. In addition, rinsing is not necessary, and the amount of solvent used can be reduced by not performing rinsing.

[0380] The developed hole pattern and trench pattern can also be shrunk by heat flow, RELACS technology or DSA technology. A shrinking agent is coated on the hole pattern, and the cross-linking of the shrinking agent is initiated on the surface of the resist film by diffusion of the acid catalyst from the resist film being baked, and the shrinking agent will adhere to the side wall of the hole pattern. The baking temperature is preferably 70-180°C, more preferably 80-170°C, and the baking time is preferably 10-300 seconds. The excess shrinking agent is removed to shrink the hole pattern.

[0381] Example

[0382] Hereinafter, the present invention will be specifically described with reference to synthesis examples, examples and comparative examples, but the present invention is not limited to the following examples.

[0383] The vinyl salicylic acid monomers a-1 to a-11, the acid-labile group-containing monomer ALG-1, and the acid-generating group-containing monomers PM-1 to PM-12 used in the synthesis of the polymer are as follows. The Mw of the polymer is a polystyrene-converted measurement value obtained by GPC using THF as a solvent.

[0384]

[0385]

[0386]

[0387] [Synthesis Example 1] Synthesis of Polymer P-1

[0388] In a 2L flask, add 0.8g of monomer a-1, 8.4g of 1-methyl-1-cyclopentyl methacrylate, 4.2g of 3-hydroxystyrene, 8.6g of monomer PM-1, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-1. The composition of polymer P-1 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0389]

[0390] [Synthesis Example 2] Synthesis of Polymer P-2

[0391] In a 2L flask, add 0.9g of monomer a-2, 8.4g of 1-methyl-1-cyclopentyl methacrylate, 4.2g of 3-hydroxystyrene, 9.8g of monomer PM-2, and 40g of THF as a solvent. Cool the reaction container to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and allow to react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-2. The composition of polymer P-2 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0392]

[0393] [Synthesis Example 3] Synthesis of Polymer P-3

[0394] In a 2L flask, add 1.0g of monomer a-3, 8.9g of 1-methyl-1-cyclopentyl methacrylate, 3.6g of 3-hydroxystyrene, 9.7g of monomer PM-3, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and allow to react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-3. The composition of polymer P-3 is obtained by 13 C-NMR and1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0395]

[0396] [Synthesis Example 4] Synthesis of Polymer P-4

[0397] In a 2L flask, add 1.2g of monomer a-4, 8.6g of 1-methyl-1-cyclopentyl methacrylate, 4.2g of 4-hydroxystyrene, 11.0g of monomer PM-4, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-4. The composition of polymer P-4 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0398]

[0399] [Synthesis Example 5] Synthesis of Polymer P-5

[0400] Add 1.4 g of monomer a-5, 11.1 g of monomer ALG-1, 4.2 g of 4-hydroxystyrene, 9.9 g of monomer PM-5, and 40 g of THF as a solvent to a 2 L flask. Cool the reaction vessel to -70 ° C in a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2 g of AIBN as a polymerization initiator, raise the temperature to 60 ° C, and react for 15 hours. Add the reaction solution to 1 L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60 ° C to obtain polymer P-5. The composition of polymer P-5 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0401]

[0402] [Synthesis Example 6] Synthesis of Polymer P-6

[0403] In a 2L flask, add 0.8g of monomer a-1, 8.4g of 1-methyl-1-cyclopentyl methacrylate, 4.2g of 4-hydroxystyrene, 12.2g of monomer PM-6, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and allow to react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-6. The composition of polymer P-6 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0404]

[0405] [Synthesis Example 7] Synthesis of Polymer P-7

[0406] In a 2L flask, add 0.8g of monomer a-1, 11.1g of monomer ALG-1, 5.4g of 4-hydroxystyrene, 11.0g of monomer PM-7, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat degassing under reduced pressure and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. Dry the obtained white solid under reduced pressure at 60°C to obtain polymer P-7. The composition of polymer P-7 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0407]

[0408] [Synthesis Example 8] Synthesis of Polymer P-8

[0409] In a 2L flask, add 0.8g of monomer a-1, 9.0g of 1-vinyl-1-cyclopentyl methacrylate, 4.2g of 3-hydroxystyrene, 11.9g of monomer PM-8, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-8. The composition of polymer P-8 is obtained by 13 C-NMR and1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0410]

[0411]

[0412] [Synthesis Example 9] Synthesis of Polymer P-9

[0413] In a 2L flask, add 0.8g of monomer a-6, 8.9g of 1-ethynyl-1-cyclopentyl methacrylate, 4.2g of 3-hydroxystyrene, 10.2g of monomer PM-9, and 40g of THF as a solvent. Cool the reaction container to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-9. The composition of polymer P-9 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0414]

[0415] [Synthesis Example 10] Synthesis of Polymer P-10

[0416] In a 2L flask, add 1.3g of monomer a-7, 11.1g of monomer ALG-1, 4.2g of 3-hydroxystyrene, 11.0g of monomer PM-10, and 40g of THF as a solvent. Cool the reaction container to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-10. The composition of polymer P-10 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0417]

[0418] [Synthesis Example 11] Synthesis of Polymer P-11

[0419] In a 2L flask, add 0.8g of monomer a-1, 11.1g of monomer ALG-1, 5.4g of 3-hydroxystyrene, 12.5g of monomer PM-11, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat degassing under reduced pressure and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. Dry the obtained white solid under reduced pressure at 60°C to obtain polymer P-11. The composition of polymer P-11 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0420]

[0421]

[0422] [Synthesis Example 12] Synthesis of Polymer P-12

[0423] In a 2L flask, add 0.8g of monomer a-1, 11.1g of monomer ALG-1, 5.4g of 3-hydroxystyrene, 10.5g of monomer PM-12, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat degassing under reduced pressure and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. Dry the obtained white solid under reduced pressure at 60°C to obtain polymer P-12. The composition of polymer P-12 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0424]

[0425] [Synthesis Example 13] Synthesis of Polymer P-13

[0426] In a 2L flask, add 1.8g of monomer a-8, 11.1g of monomer ALG-1, 4.6g of 3-hydroxystyrene, 10.5g of monomer PM-12, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat degassing under reduced pressure and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-13. The composition of polymer P-13 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0427]

[0428] [Synthesis Example 14] Synthesis of Polymer P-14

[0429] In a 2L flask, add 3.0g of monomer a-9, 11.1g of monomer ALG-1, 4.6g of 3-hydroxystyrene, 10.5g of monomer PM-12, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-14. The composition of polymer P-14 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0430]

[0431] [Synthesis Example 15] Synthesis of Polymer P-15

[0432] In a 2L flask, add 1.9g of monomer a-10, 11.1g of monomer ALG-1, 4.6g of 3-hydroxystyrene, 10.5g of monomer PM-12, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat degassing under reduced pressure and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-15. The composition of polymer P-15 is obtained by 13 C-NMR and1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0433]

[0434] [Synthesis Example 16] Synthesis of Polymer P-16

[0435] In a 2L flask, add 2.5g of monomer a-11, 11.1g of monomer ALG-1, 4.6g of 3-hydroxystyrene, 10.5g of monomer PM-12, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen environment, and repeat degassing under reduced pressure and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, raise the temperature to 60°C, and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-16. The composition of polymer P-16 is obtained by 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0436]

[0437]

[0438] [Comparative Synthesis Example 1] Synthesis of Comparative Polymer cP-1

[0439] A comparative polymer cP-1 was obtained in the same manner as in Synthesis Example 1 except that the monomer a-1 was not used. The composition of the comparative polymer cP-1 is 13 C-NMR and 1 The Mw and Mw / Mn were confirmed by H-NMR, and those by GPC.

[0440]

[0441] [Examples 1 to 18, Comparative Example 1] Preparation and Evaluation of Resist Materials

[0442] A solution prepared by dissolving the components shown in Table 1 in a solvent in which 50 ppm of a surfactant, Polyfox 636 manufactured by Omnova, was dissolved as a surfactant was filtered through a filter having a size of 0.2 μm to prepare a positive resist material.

[0443] In Table 1, the components are as follows.

[0444] Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

[0445] DAA (Diacetone Alcohol)

[0446] EL(ethyl lactate)

[0447] Acid generator: PAG-1, PAG-2

[0448]

[0449]

[0450] Quencher: Q-1

[0451]

[0452] (2) EUV lithography evaluation

[0453] Each positive resist material shown in Table 1 was spin-coated on a Si substrate on which a silicon-containing spin-coated hard mask SHB-A940 (silicon content 43 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 prepare a positive resist film with a film thickness of 40 nm. The resist film was exposed using an EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.7, dipole illumination) manufactured by ASML, and PEB was performed for 60 seconds on a hot plate at the temperature described in Table 1, and developed for 30 seconds with a 2.38 mass % TMAH aqueous solution to form a straight line and space pattern with a pitch of 32 nm and a line width of 16 nm.

[0454] The exposure amount when the line pattern is formed with a size of 16nm±1.6nm was determined using CD-SEM (CG6300) manufactured by Hitachi Advanced Technology Co., Ltd., and the LWR at this exposure amount was measured. The wafer was cut, and the cross section of the 16nm straight line and space pattern was observed using SEM (S-4800) manufactured by Hitachi Advanced Technology Co., Ltd. to observe whether there was tailing in the space part. The results are shown in Table 1.

[0455] [Table 1]

[0456]

[0457]

[0458] Based on the results shown in Table 1, it can be understood that the positive resist material of the present invention comprising a base polymer, wherein the base polymer contains: a repeating unit a having a substituted or unsubstituted carboxyl group and a substituted or unsubstituted phenolic hydroxyl group (however, having at least one selected from an unsubstituted carboxyl group and an unsubstituted phenolic hydroxyl group), a repeating unit b having an acid-labile group, and a repeating unit c consisting of a sulfonium anion and a sulfonium cation or an iodonium cation bonded to the polymer main chain, has sufficient sensitivity and satisfies the effect of reducing the tailing of the LWR and the spacer portion.

Claims

1. A positive resist material, comprising a base polymer, wherein the base polymer contains: A repeating unit a having a substituted or unsubstituted carboxyl group and a substituted or unsubstituted phenolic hydroxyl group, wherein the repeating unit a has at least one selected from the group consisting of an unsubstituted carboxyl group and an unsubstituted phenolic hydroxyl group, a repeating unit b having an acid-labile group, and The repeating unit c has a sulfonium salt or iodonium salt structure of a sulfonic acid bonded to the main chain of the polymer.

2. The positive resist material according to claim 1, wherein The repeating unit a is represented by the following formula (a); In the formula, k is 0 or 1; m is an integer from 1 to 4; n is an integer from 0 to 4; R A is a hydrogen atom or a methyl group; X 1 is a single bond or an ester bond; X 2 It is a single bond, a saturated alkylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group; X 3 is a single bond, an ester bond, an ether bond or a carbonyl group; R 1 is an alkyl group having 1 to 4 carbon atoms or a halogen atom; R 2 is a hydrogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 7 carbon atoms, or a saturated hydrocarbon oxycarbonyl group having 2 to 7 carbon atoms; R 3 is a hydrogen atom, a saturated hydrocarbon group having 1 to 12 carbon atoms, or an unsaturated hydrocarbon group having 2 to 12 carbon atoms, and the saturated hydrocarbon group and the unsaturated hydrocarbon group may also have at least one selected from a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, and a halogen atom; however, when m is 1, R 2 and R 3 When one or both of them are hydrogen atoms and m is 2, 3 or 4, multiple R 2 and R 3 At least one of them is a hydrogen atom.

3. The positive resist material according to claim 1, wherein The repeating unit b is composed of at least one selected from the repeating unit b1 represented by the following formula (b1) and the repeating unit b2 represented by the following formula (b2); In the formula, R A are each 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 and comprising at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, the naphthylene group, and the linking group may also have at least one selected from a halogen atom, a nitro group, a hydroxyl group, a saturated hydrocarbonoxy group having 1 to 8 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 8 carbon atoms, and a saturated hydrocarbonoxycarbonyloxy group having 2 to 8 carbon atoms; Y 2 is a single bond, an ester bond or an amide bond; Y 3 is a single bond, an ether bond or an ester bond; R 11 and R 12 It is an acid-labile group; R 13 is a fluorine atom, a trifluoromethyl group, a cyano group, or an alkyl group having 1 to 6 carbon atoms; R 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a portion of the -CH2- of the alkanediyl group may be substituted by an ether bond or an ester bond; a is 1 or 2; b is an integer from 0 to 4; but 1≤a+b≤5.

4. The positive resist material according to claim 1, wherein The repeating unit c is composed of at least one selected from the repeating units represented by the following formulae (c1) to (c5); In the formula, R A are each independently a hydrogen atom or a methyl group; R B Each independently is a hydrogen atom or 6 Bonding to form a ring is also possible; Z 1 is a single bond, an aliphatic alkylene 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 groups, or -OZ 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -;Z 11 It is an aliphatic alkylene 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 them; and it may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group; Z 2 is a single bond or an ester bond; Z 3 is a single bond, -Z 31 -C(=O)-O- or -Z 31 -O-;Z 31 It is a carbonyl group having 1 to 12 carbon atoms, a phenylene group, or a group having 7 to 18 carbon atoms obtained by combining them; it may also contain a carbonyl group, a nitro group, a cyano group, an ester bond, an ether bond, a carbamate bond, a fluorine atom, an iodine atom, or a bromine atom; Z 4 is a single bond, methylene or ethylene; Z 5 is a single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OZ 51 -、-C(=O)-OZ 51 -or-C(=O)-NH-Z 51 -;Z 51 It is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a methylphenylene group, a dimethylphenylene group, a fluorinated phenylene group or a phenylene group substituted with a trifluoromethyl group, and may also contain a carbonyl group, an ester bond, an ether bond, a hydroxyl group or a halogen atom; Z 6 is a single bond, a phenylene ring, a naphthylene ring, an ester bond, or an amide bond; Z 7A is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom; Z 7B is a monovalent organic group having 1 to 10 carbon atoms, and may have at least one atom selected from a halogen atom, an oxygen atom, a nitrogen atom and a sulfur atom; Z 8 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms; Z 9 is a trivalent organic group having 1 to 12 carbon atoms, and may have at least one atom selected from an oxygen atom, a nitrogen atom and a sulfur atom; R 1 ~Rf 4 Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group; and Rf 1 and Rf 2 They can also combine to form a carbonyl group; R 21 and R 22 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom; R 23 is a saturated hydrocarbon 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; R is a (d+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms; d is an integer from 0 to 5; X - It is a non-nucleophilic counter ion; M + It is a sulfonium cation or an iodonium cation.

5. The positive resist material according to claim 4, wherein Z 3 , Z 7A , Z 7B or M + The iodine atom is one containing at least one iodine atom.

6. The positive resist material according to claim 1, wherein The base polymer further comprises a repeating unit d having an adhesion group selected from a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether bond, an ester bond, a sulfonate bond, a cyano group, an amide group, -OC(=O)-S- and -OC(=O)-NH-. The positive resist material according to claim 1 , further comprising an acid generator. The positive resist material according to claim 1 , further comprising an organic solvent. 9 . The positive resist material according to claim 1 , further comprising a quencher. 10 . The positive resist material according to claim 1 , further comprising a surfactant.

11. A pattern forming method comprising the following steps: forming a resist film on a substrate using the positive resist material according to any one of claims 1 to 10; exposing the resist film to high energy radiation; The exposed resist film is developed using a developer.

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

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