Chemically amplified negative resist composition and resist pattern forming method

Abstract

The invention relates to a chemically amplified negative resist composition and a resist pattern forming method. The present invention addresses the problem of providing: a chemically amplified negative resist composition which is capable of obtaining a resist pattern having improved resolution during pattern formation and excellent LER and pattern loyalty; and a method for forming a resist pattern. The chemically amplified negative resist composition comprises (A) a photoacid generator comprising an onium salt represented by the following formula (A), and (B) a base polymer containing a polymer containing a repeating unit represented by the following formula (B1). # imgabs0 #

Description

Technical Field

[0001] The invention relates to a chemically amplified negative resist composition and a resist pattern forming method. Background Art

[0002] In recent years, with the high integration and high speed of LSI, the pattern rules are also rapidly becoming finer. Among them, the processing of patterns below 0.2μm mainly uses chemically amplified resist compositions using acids as catalysts. In addition, high-energy rays such as ultraviolet rays, far ultraviolet rays, and electron beams (EB) are used as exposure sources. EB lithography, which is particularly used as an ultra-fine processing technology, is indispensable as a processing method for blank photomasks when making photomasks for semiconductor manufacturing.

[0003] Polymers containing a large amount of aromatic skeletons having acidic side chains, such as polyhydroxystyrene, are useful as materials for KrF lithography resist compositions using KrF excimer lasers, but they exhibit large absorption for light with a wavelength of around 200 nm, and therefore are not used as materials for ArF lithography resist compositions using ArF excimer lasers. However, they are important materials for EB lithography resist compositions or extreme ultraviolet (EUV) lithography resist compositions, which are powerful technologies for forming patterns smaller than the processing limit of ArF excimer lasers, from the perspective of obtaining high etching resistance.

[0004] In the processing of blank photomasks, there are those with surface materials such as chromium compound films represented by chromium oxide formed on the photomask substrate that are easy to affect the pattern shape of the chemically amplified resist film. In order to maintain high resolution and the shape after etching, it is not dependent on the type of substrate and one of the important properties is to keep the pattern outline of the resist film rectangular. In addition, in recent years, in order to achieve miniaturization, MBMW (Multi-Beam Mask Writing) drawing processing is sometimes used in the processing of blank masks. At this time, the resist composition uses a low-sensitivity resist composition (high-dose area) that is beneficial to roughness, and the optimization of the resist composition in this high-dose area has also received attention.

[0005] The resist composition used in optical lithography includes a positive type that dissolves the exposed part to form a pattern and a negative type that leaves the exposed part to form a pattern. The one that is easy to use is selected according to the form of the required resist pattern. Chemically amplified negative resist compositions usually contain a polymer that dissolves in an aqueous alkaline developer, an acid generator that decomposes and generates an acid due to exposure light, and a crosslinking agent that forms crosslinks between polymers using the acid as a catalyst to make the polymer insoluble in the developer (sometimes the polymer and the crosslinking agent are integrated). In addition, a quencher is usually added to control the diffusion of the acid generated by exposure.

[0006] As for the alkali-soluble units constituting the aforementioned polymer dissolved in the aqueous alkaline developer, the units derived from phenols can be cited. In the past, such negative resist compositions were particularly developed in large quantities for exposure by KrF excimer lasers. However, when the exposure light has a wavelength of 150 to 220 nm, since the units derived from phenols do not have light transmittance, they are not used as ArF excimer laser users. However, in recent years, as a negative resist composition for exposure methods for obtaining finer patterns, i.e., short-wavelength exposure light such as EB and EUV, it has again attracted attention, for example, as reported in Patent Documents 1, 2 and 3.

[0007] Furthermore, as one of the acid generators, there is a sulfonium salt that generates a sulfonic acid having an aromatic group containing an iodine atom, as described in Patent Document 4. The sulfonium salt is focused on the sensitivity enhancement effect in EUV lithography, and its function is mainly to operate as a quencher for fluorinated alkanesulfonic acid. No research has been conducted on the acid generator used as an acid generator, especially as an acid generator used in a negative resist composition using polyhydroxystyrene as a base polymer used in an EB drawing process in a blank mask process.

[0008] In addition, in optical lithography, various improvements have been made by changing the selection and combination of materials used in resist compositions, process conditions, etc., in order to control sensitivity and pattern profiles. One of the focuses of the improvements is the problem of acid diffusion, which has a significant impact on the resolution of chemically amplified resist compositions.

[0009] The quencher is a substance that inhibits acid diffusion, and is actually a necessary component for improving the performance of the resist composition, especially the resolution. Various studies have been conducted on the quencher so far, and generally amines and weak acid onium salts are used. For the example of weak acid onium salts, Patent Document 5 records that by adding triphenylsulfonium acetate, a good resist pattern without T-top formation, line width difference between isolated patterns and dense patterns, and standing waves can be formed. Patent Document 6 records that by adding ammonium sulfonate or ammonium carboxylate, sensitivity, resolution and exposure latitude can be improved. In addition, Patent Document 7 records a resist composition for KrF lithography and EB lithography containing a combination of a photoacid generator that generates a carboxylic acid containing a fluorine atom, which has excellent resolution and improves process latitude such as exposure latitude and depth of focus. In addition, Patent Document 8 records a resist composition for F2 lithography using an F2 laser containing a photoacid generator that generates a carboxylic acid containing a fluorine atom, which has excellent line edge roughness (LER) and improves the problem of tailing. They are used in KrF lithography, EB lithography or F2 lithography.

[0010] Patent Document 9 also describes a positive photosensitive composition for ArF lithography of carboxylic acid onium salts. These compositions are characterized by the strong acid (sulfonic acid) generated from the photoacid generator due to exposure exchanging with the weak acid onium salt to form a weak acid and a strong acid onium salt, and the strong acid (sulfonic acid) with high acidity is replaced by a weak acid (carboxylic acid), thereby inhibiting the acid decomposition reaction of the acid-labile group and shortening (controlling) the acid diffusion distance, and apparently functioning as a quencher.

[0011] However, in recent years, not only the roughness is further improved, but also the resist composition with excellent line and space (LS), isoline (IL), isospace (IS) and dot pattern shape is sought. The photoacid generator described in Patent Document 10 generates a large acid volume and the diffusion of the acid is suppressed. Although it can obtain a pattern with good resolution and roughness, it has the disadvantage that rounded corners can be observed in the dot pattern.

[0012] Prior art literature

[0013] Patent Literature

[0014] [Patent Document 1] Japanese Patent Application Publication No. 2006-201532

[0015] [Patent Document 2] Japanese Patent Application Publication No. 2006-215180

[0016] [Patent Document 3] Japanese Patent Application Publication No. 2008-249762

[0017] [Patent Document 4] Japanese Patent No. 6645464

[0018] [Patent Document 5] Japanese Patent No. 3955384

[0019] [Patent Document 6] Japanese Patent Application Laid-Open No. 11-327143

[0020] [Patent Document 7] Japanese Patent No. 4231622

[0021] [Patent Document 8] Japanese Patent No. 4116340

[0022] [Patent Document 9] Japanese Patent No. 4226803

[0023] [Patent Document 10] Japanese Patent No. 6248882 Summary of the invention

[0024] [Problems to be solved by the invention]

[0025] The present invention is made in view of the above situation, and an object of the present invention is to provide a chemically amplified negative resist composition and a resist pattern forming method that can improve the resolution during pattern formation and obtain a resist pattern with good LER and pattern fidelity.

[0026] [Methods to solve the problem]

[0027] As a result of repeated and in-depth studies to achieve the aforementioned objectives, the inventors of the present application have obtained the following insights and have completed the present invention: when an alkanesulfonic acid-type onium salt having a bulky substituent at the α-position of the sulfonic group of the anion and a bulky aromatic ring structure is introduced into the resist composition as an acid generator, the generated acid will have appropriate acidity, and at the same time, due to the bulky anion structure, the rotation of the connecting group is suppressed, thereby suppressing excessive diffusion of the acid, and thus a pattern with a small LER can be obtained. In addition, in the dot pattern, due to the appropriate dissolution barrier, a pattern with good rectangularity can be obtained.

[0028] That is, the present invention provides the following chemically amplified negative resist composition and resist pattern forming method.

[0029] 1. A chemically amplified negative resist composition comprising:

[0030] (A) a photoacid generator composed of an onium salt represented by the following formula (A), and

[0031] (B) The base polymer comprises a polymer having a repeating unit represented by the following formula (B1).

[0032] [Chemistry 1]

[0033]

[0034] In the formula, n1 is an integer of 0 to 2. n2 is an integer of 2 to 5 when n1=0, an integer of 2 to 7 when n1=1, and an integer of 2 to 9 when n1=2.

[0035] L is a single bond, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, or a urethane bond.

[0036] R 1 and R 2 Each of R is independently a hydrogen atom or a branched or cyclic hydrocarbon group having 3 to 20 carbon atoms which may contain a hetero atom, but not all of them are hydrogen atoms. 1 With R 2 They may also bond to each other and to the carbon atoms to which they are bonded to form a ring.

[0037] R 3 are each independently an iodine atom or a branched or cyclic hydrocarbon group having 3 to 20 carbon atoms which may contain a hetero atom, and at least one R3 Bonded to the carbon atom adjacent to the carbon atom to which L is bonded.

[0038] Z + It is an onium cation.

[0039] [Chemistry 2]

[0040]

[0041] In the formula, a1 is 0 or 1. a2 is an integer of 0 to 2. a3 is an integer satisfying 0≤a3≤5+2(a2)-a4. a4 is an integer of 1 to 3.

[0042] R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0043] R 11 It is a halogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom.

[0044] A 1 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of the -CH2- of the saturated alkylene group may be substituted by -O-.

[0045] 2. The chemically amplified negative resist composition according to 1., wherein the component (A) is an onium salt represented by the following formula (A1).

[0046] [Chemistry 3]

[0047]

[0048] In the formula, L, R 1 , R 2 , R 3 and Z + Same as above. n3 is an integer of 1 to 4.

[0049] 3. The chemically amplified negative resist composition according to 2., wherein the component (A) is an onium salt represented by the following formula (A2).

[0050] [Chemistry 4]

[0051]

[0052] In the formula, n3, R 1 , R 2 , R 3 and Z + Same as above.

[0053] 4. The chemically amplified negative resist composition according to any one of 1. to 3., wherein Z + It is a sulfonium cation represented by the following formula (cation-1) or an iodonium cation represented by the following formula (cation-2).

[0054] [Chemistry 5]

[0055]

[0056] In the formula, R ct1 ~R ct5 are each independently a halogen atom or a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom. ct1 and R ct2 They may also bond to each other and to the sulfur atom to which they are bonded to form a ring.

[0057] 5. The chemically amplified negative resist composition according to any one of 1. to 4., wherein the polymer further comprises a repeating unit represented by the following formula (B2).

[0058] [Chemistry 6]

[0059]

[0060] In the formula, b1 is 0 or 1. b2 is an integer from 0 to 2. b3 is an integer satisfying 0≤b3≤5+2(b2)-b4. b4 is an integer from 1 to 3.

[0061] R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0062] R 12 It is a halogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom.

[0063] R 13 and R 14 Each of R is independently a hydrogen atom, a saturated hydrocarbon group having 1 to 15 carbon atoms which may be substituted with a hydroxyl group or a saturated hydrocarbon oxy group, or an aryl group which may have a substituent. 13 and R 14 cannot be a hydrogen atom at the same time. 13 and R 14 They may also bond to each other and to the carbon atoms to which they are bonded to form a ring.

[0064] A 2 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of the -CH2- of the saturated alkylene group may be substituted by -O-.

[0065] W1 It is a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aryl group which may have a substituent.

[0066] 6. A chemically amplified negative resist composition as described in any one of 1. to 5., wherein the polymer further contains at least one of a repeating unit represented by the following formula (B3), a repeating unit represented by the following formula (B4) and a repeating unit represented by the following formula (B5).

[0067] [Chemistry 7]

[0068]

[0069] In the formula, c and d are each independently an integer of 0 to 4. e1 is 0 or 1. e2 is an integer of 0 to 5. e3 is an integer of 0 to 2.

[0070] R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0071] R 21 and R 22 Each of them is independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group having 1 to 8 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom.

[0072] R 23 It is a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 20 carbon atoms, a saturated hydrocarbon oxyhydrocarbyl group having 2 to 20 carbon atoms, a saturated hydrocarbon thiohydrocarbyl group having 2 to 20 carbon atoms, a halogen atom, a nitro group, a cyano group, a saturated hydrocarbon sulfinyl group having 1 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl group having 1 to 20 carbon atoms.

[0073] A 3 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of the -CH2- of the saturated alkylene group may be substituted by -O-.

[0074] 7. The chemically amplified negative resist composition of 5. wherein the polymer further comprises at least one selected from the group consisting of a repeating unit represented by the following formula (B6), a repeating unit represented by the following formula (B7), a repeating unit represented by the following formula (B8), a repeating unit represented by the following formula (B9), a repeating unit represented by the following formula (B10), a repeating unit represented by the following formula (B11), a repeating unit represented by the following formula (B12), and a repeating unit represented by the following formula (B13).

[0075] [Chemistry 8]

[0076]

[0077] In the formula, R B are each independently a hydrogen atom or a methyl group.

[0078] Y 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 *-OY 11 -, *-C(=O)-OY 11 - or *-C(=O)-NH-Y 11 -, and Y 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 these groups, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0079] Y 2 is a single bond or **-Y 21 -C(=O)-O-, and Y 21 It is a hydrocarbylene group having 1 to 20 carbon atoms which may contain a hetero atom.

[0080] Y 3 is a single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, *-OY 31 -, *-C(=O)-OY 31 - or *-C(=O)-NH-Y 31 -.Y 31 It is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, a phenylene group substituted with a trifluoromethyl group, or a group having 7 to 20 carbon atoms obtained by combining these groups, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0081] * is an atomic bond to a carbon atom in the main chain, and ** is an atomic bond to an oxygen atom in the formula.

[0082] Y 4 It is a single bond or a alkylene group having 1 to 30 carbon atoms which may contain a hetero atom.

[0083] f1 and f2 are independently 0 or 1, but in Y 4 When it is a single bond, f1 and f2 are 0.

[0084] R 31 ~R 48 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. 31 and R 32 They may also be bonded to each other and to the sulfur atom to which they are bonded to form a ring, and R 33 and R 34 , R 36 and R 37 , or R39 and R 40 They may also bond to each other and to the sulfur atom to which they are bonded to form a ring.

[0085] R HF is a hydrogen atom or a trifluoromethyl group.

[0086] XA - It is a non-nucleophilic relative ion.

[0087] 8. A chemically amplified negative resist composition as described in 7., wherein the polymer contains a repeating unit represented by the following formula (B1-1), a repeating unit represented by the following formula (B2-1) or a repeating unit represented by the following formula (B2-2), and a repeating unit represented by the following formula (B7).

[0088] [Chemistry 9]

[0089]

[0090] In the formula, a4, b4, R A , R B , Y 2 , R 13 , R 14 , R 33 , R 34 , R 35 and R HF Same as above.

[0091] 9. The chemically amplified negative resist composition of 7., wherein the base polymer (B) further comprises a polymer containing repeating units represented by formula (B1) and repeating units represented by formula (B2) and does not contain repeating units represented by formulas (B6) to (B13).

[0092] 10. The chemically amplified negative resist composition according to any one of 1. to 9., wherein the content of repeating units having an aromatic ring skeleton in all repeating units of the polymer contained in the base polymer is 60 mol% or more.

[0093] 11. The chemically amplified negative resist composition according to any one of 1. to 10., further comprising (C) a cross-linking agent.

[0094] 12. The chemically amplified negative resist composition of 5., which does not contain a cross-linking agent.

[0095] 13. The chemically amplified negative resist composition as described in any one of 1. to 12. further contains (D) a fluorine atom-containing polymer, wherein the (D) fluorine atom-containing polymer contains at least one of a repeating unit represented by the following formula (D1), a repeating unit represented by the following formula (D2), a repeating unit represented by the following formula (D3) and a repeating unit represented by the following formula (D4), and contains or does not contain at least one of a repeating unit represented by the following formula (D5) and a repeating unit represented by the following formula (D6).

[0096] [Chemistry 10]

[0097]

[0098] In the formula, x is an integer of 1 to 3. y is an integer satisfying 0≤y≤5+2z-x. z is 0 or 1. k is an integer of 1 to 3.

[0099] R C are each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0100] R D are each independently a hydrogen atom or a methyl group.

[0101] R 101 , R 102 , R 104 and R 105 Each independently represents a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms.

[0102] R 103 , R 106 , R 107 and R 108 are independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-labile group, and R 103 , R 106 , R 107 and R 108 In the case of a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group may be inserted between carbon-carbon bonds.

[0103] R 109 It is a hydrogen atom or a linear or branched hydrocarbon group having 1 to 5 carbon atoms, which may have a heteroatom-containing group inserted between carbon-carbon bonds.

[0104] R 110 It is a linear or branched hydrocarbon group having 1 to 5 carbon atoms, which may have a heteroatom-containing group inserted between carbon-carbon bonds.

[0105] R 111 It is a saturated hydrocarbon group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted by a fluorine atom, and a part of the -CH2- group of the saturated hydrocarbon group may be substituted by an ester bond or an ether bond.

[0106] Z 1 It is a (k+1)-valent hydrocarbon group having 1 to 20 carbon atoms or a (k+1)-valent fluorinated hydrocarbon group having 1 to 20 carbon atoms.

[0107] Z 2 It is a single bond, *-C(=O)-O- or *-C(=O)-NH-. * is an atomic bond to a carbon atom of the main chain.

[0108] Z 3 is a single bond, -O-, *-C(=O)-OZ 31 -Z 32 - or *-C(=O)-NH-Z 31 -Z 32 -.Z 31 Z is a single bond or a saturated alkylene group having 1 to 10 carbon atoms. 32 is a single bond, ester bond, ether bond or sulfonamide bond. * is an atomic bond to a carbon atom of the main chain.

[0109] 14. The chemically amplified negative resist composition according to any one of 1. to 13., further comprising (E) a quencher.

[0110] 15. The chemically amplified negative resist composition according to 14., wherein the content ratio of the (A) acid generator to the (E) quencher is less than 6 in terms of mass ratio.

[0111] 16. The chemically amplified negative resist composition according to any one of 1. to 15., further comprising (F) an organic solvent.

[0112] 17. A method for forming a resist pattern, comprising the following steps: forming a resist film on a substrate using a chemically amplified negative resist composition as described in any one of 1. to 16., irradiating the resist film with a pattern using high-energy rays, and developing the resist film irradiated with the pattern using an alkaline developer.

[0113] 18. The resist pattern forming method according to 17., wherein the high-energy ray is EUV or EB.

[0114] 19. The resist pattern forming method according to 17. or 18., wherein the outermost surface of the substrate is made of a material containing at least one selected from the group consisting of chromium, silicon, tantalum, molybdenum, cobalt, nickel, tungsten and tin.

[0115] 20. The resist pattern forming method according to any one of 17. to 19., wherein the substrate is a transmission type or reflection type blank mask.

[0116] 21. A transmission or reflection type blank mask coated with the chemically amplified negative resist composition as described in any one of 1. to 16.

[0117] [Effects of the Invention]

[0118] The chemically amplified negative resist composition of the present invention can effectively control the acid diffusion caused by exposure during pattern formation by the action of the onium salt represented by formula (A), and when the resist film is formed to form a pattern, a pattern with extremely high resolution, high pattern fidelity and reduced LER can be obtained. In addition, by the action of the repeating unit represented by formula (B1), the adhesion of the resist film to the substrate during film formation can be improved, and the solubility in the alkaline developer can be controlled. DETAILED DESCRIPTION

[0119] Hereinafter, the present invention will be described in detail. In addition, in the following description, sometimes, depending on the structure represented by the chemical formula, there is an asymmetric carbon, and there may be mirror image isomers and diastereomers. In this case, these isomers are represented by one chemical formula. These isomers can be used alone or in the form of a mixture of two or more.

[0120] [Chemically amplified negative resist composition]

[0121] The chemically amplified negative resist composition of the present invention is characterized by containing: (A) a photoacid generator composed of an alkanesulfonic acid type onium salt having a bulky substituent at the α-position of the sulfonic group of the anion and having a bulky aromatic ring structure, and (B) a base polymer containing a predetermined polymer.

[0122] [(A) Acid Generator]

[0123] The onium salt of the acid generator as the component (A) is represented by the following formula (A).

[0124] [Chemistry 11]

[0125]

[0126] In formula (A), n1 is an integer of 0 to 2. When n1=0, it represents a benzene ring, when n1=1, it represents a naphthalene ring, and when n1=2, it represents an anthracene ring. From the viewpoint of solvent solubility, a benzene ring with n1=0 is preferred. When n1=0, n2 is an integer of 2 to 5, when n1=1, it is an integer of 2 to 7, and when n1=2, it is an integer of 2 to 9.

[0127] In formula (A), L is a single bond, an ether bond, an ester bond, a sulfonate bond, a carbonate bond or a urethane bond. Among them, an ester bond or a sulfonate bond is preferred, and a sulfonate bond is more preferred.

[0128] In formula (A), R 1 and R 2 Each of R is independently a hydrogen atom or a branched or cyclic hydrocarbon group having 3 to 20 carbon atoms which may contain a hetero atom, but not all of them are hydrogen atoms.1 and R 2 When all are hydrogen atoms or straight-chain hydrocarbon groups, due to -SO3 - The bulkiness near the base is insufficient, so the apparent acid diffusion cannot be suppressed, and the photolithography performance will deteriorate.

[0129] R 1 and R 2 The hydrocarbon group represented by may be saturated or unsaturated, and specific examples thereof include: branched alkyl groups having 3 to 20 carbon atoms, such as isopropyl, sec-butyl, tert-butyl, tert-pentyl, and 2-ethylhexyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, oxanorbornyl, tricyclo[5.2.1.0 2,6 ] cyclic aliphatic hydrocarbon groups having 3 to 20 carbon atoms, such as decyl and adamantyl; aryl groups having 6 to 20 carbon atoms, such as phenyl, naphthyl, anthracenyl; and groups obtained by combining them, but not limited thereto. In addition, part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and part of -CH2- of the aforementioned hydrocarbon group may be substituted by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms, and as a result, hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sultone rings, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl groups, and the like may be contained. Examples of the aforementioned halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, but among them, fluorine atoms and iodine atoms are preferred.

[0130] Again, R 1 With R 2 They may also be bonded to each other and form a ring together with the carbon atoms to which they are bonded. Examples of the ring formed in this case include: cyclopropane ring, cyclobutane ring, cyclopentane ring, cyclohexane ring, norbornane ring, adamantane ring, etc. In addition, part or all of the hydrogen atoms in the aforementioned ring may be substituted by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and part of -CH2- in the aforementioned ring may be substituted by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, etc., and as a result, it may also contain hydroxyl, cyano, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sultone rings, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl groups, etc.

[0131] In formula (A), R 3 are each independently an iodine atom or a branched or cyclic hydrocarbon group having 3 to 20 carbon atoms which may contain a hetero atom, and at least one R 3 is bonded to a carbon atom adjacent to the carbon atom bonded to L. Specific examples of the above hydrocarbon group include and are exemplified as R 1and R 2 The same examples are given for the hydrocarbon groups represented.

[0132] R in formula (A) 3 The structure formed by bonding with an aromatic ring includes the following, but is not limited thereto. In the following formula, the dotted line is an atomic bond with L.

[0133] [Chemistry 12]

[0134]

[0135] [Chemistry 13]

[0136]

[0137] [Chemistry 14]

[0138]

[0139] [Chemistry 15]

[0140]

[0141] [Chemistry 16]

[0142]

[0143] [Chemistry 17]

[0144]

[0145] The onium salt represented by the formula (A) is preferably represented by the following formula (A1).

[0146] [Chemistry 18]

[0147]

[0148] In the formula, L, R 1 , R 2 , R 3 and Z + Same as above. n3 is an integer of 1 to 4. The onium salt represented by formula (A1) is preferably represented by the following formula (A2).

[0149] [Chemistry 19]

[0150]

[0151] In the formula, n3, R 1 , R 2 , R 3 and Z + Same as above.

[0152] Particularly preferred examples of the anion of the onium salt represented by the formula (A) include those shown below, but are not limited thereto.

[0153] [Chemistry 20]

[0154]

[0155] [Chemistry 21]

[0156]

[0157] [Chemistry 22]

[0158]

[0159] [Chemistry 23]

[0160]

[0161] [Chemistry 24]

[0162]

[0163] [Chemistry 25]

[0164]

[0165] [Chemistry 26]

[0166]

[0167] [Chemistry 27]

[0168]

[0169] [Chemistry 28]

[0170]

[0171] [Chemistry 29]

[0172]

[0173] [Chemistry 30]

[0174]

[0175] [Chemistry 31]

[0176]

[0177] [Chemistry 32]

[0178]

[0179] [Chemistry 33]

[0180]

[0181] [Chemistry 34]

[0182]

[0183] [Chemistry 35]

[0184]

[0185] [Chemistry 36]

[0186]

[0187] [Chemistry 37]

[0188]

[0189] [Chemistry 38]

[0190]

[0191] [Chemistry 39]

[0192]

[0193] [Chemistry 40]

[0194]

[0195] [Chemistry 41]

[0196]

[0197] [Chemistry 42]

[0198]

[0199] [Chemistry 43]

[0200]

[0201] [Chemistry 44]

[0202]

[0203] [Chemistry 45]

[0204]

[0205] [Chemistry 46]

[0206]

[0207] [Chemistry 47]

[0208]

[0209] [Chemistry 48]

[0210]

[0211] [Chemistry 49]

[0212]

[0213] [Chemistry 50]

[0214]

[0215] [Chemistry 51]

[0216]

[0217] [Chemistry 52]

[0218]

[0219] [Chemistry 53]

[0220]

[0221] [Chemistry 54]

[0222]

[0223] [Chemistry 55]

[0224]

[0225] [Chemistry 56]

[0226]

[0227] [Chemistry 57]

[0228]

[0229] [Chemistry 58]

[0230]

[0231] [Chemistry 59]

[0232]

[0233] [Chemistry 60]

[0234]

[0235] [Chemistry 61]

[0236]

[0237] [Chemistry 62]

[0238]

[0239] [Chemistry 63]

[0240]

[0241] [Chemistry 64]

[0242]

[0243] [Chemistry 65]

[0244]

[0245] [Chemistry 66]

[0246]

[0247] [Chemistry 67]

[0248]

[0249] [Chemistry 68]

[0250]

[0251] [Chemistry 69]

[0252]

[0253] [Chemistry 70]

[0254]

[0255] [Chemistry 71]

[0256]

[0257] [Chemistry 72]

[0258]

[0259] [Chemistry 73]

[0260]

[0261] [Chemistry 74]

[0262]

[0263] [Chemistry 75]

[0264]

[0265] [Chemistry 76]

[0266]

[0267] [Chemistry 77]

[0268]

[0269] [Chemistry 78]

[0270]

[0271] [Chemistry 79]

[0272]

[0273] [Chemistry 80]

[0274]

[0275] In formula (A), Z + The onium cation is preferably a sulfonium cation represented by the following formula (cation-1) or an iodonium cation represented by the following formula (cation-2).

[0276] [Chemistry 81]

[0277]

[0278] In formula (cation-1) and (cation-2), R ct1 ~R ct5 Each is independently a halogen atom or a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom.

[0279] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0280] 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 30 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl; cyclic saturated hydrocarbon groups having 3 to 30 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, and adamantyl; alkenyl groups having 2 to 30 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated hydrocarbon groups having 3 to 30 carbon atoms, such as cyclohexenyl; aryl groups having 6 to 30 carbon atoms, such as phenyl, naphthyl, and thienyl; aralkyl groups having 7 to 30 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl; and groups obtained by combining them, preferably aryl groups. 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, and as a result, it may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sultone rings, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl groups, and the like.

[0281] Again, R ct1 and R ct2 They may be bonded to each other and form a ring together with the sulfur atom to which they are bonded. In this case, the sulfonium cation represented by the formula (cation-1) includes the following.

[0282] [Chemistry 82]

[0283]

[0284] In the formula, the dotted line is and R ct3 of atomic bonds.

[0285] Examples of the sulfonium cation represented by the formula (cation-1) include the following, but are not limited thereto.

[0286] [Chemistry 83]

[0287]

[0288] [Chemistry 84]

[0289]

[0290] [Chemistry 85]

[0291]

[0292] [Chemistry 86]

[0293]

[0294] [Chemistry 87]

[0295]

[0296] [Chemistry 88]

[0297]

[0298] [Chemistry 89]

[0299]

[0300] [Chemistry 90]

[0301]

[0302] [Chemistry 91]

[0303]

[0304] [Chemistry 92]

[0305]

[0306] [Chemistry 93]

[0307]

[0308] [Chemistry 94]

[0309]

[0310] [Chemistry 95]

[0311]

[0312] [Chemistry 96]

[0313]

[0314] [Chemistry 97]

[0315]

[0316] [Chemistry 98]

[0317]

[0318] [Chemistry 99]

[0319]

[0320] [Chemical 100]

[0321]

[0322] [Chemistry 101]

[0323]

[0324] [Chemistry 102]

[0325]

[0326] [Chemistry 103]

[0327]

[0328] [Chemistry 104]

[0329]

[0330] [Chemistry 105]

[0331]

[0332] [Chemistry 106]

[0333]

[0334] [Chemistry 107]

[0335]

[0336] [Chemistry 108]

[0337]

[0338] Examples of the iodonium cation represented by the formula (cation-2) include the following, but are not limited thereto.

[0339] [Chemistry 109]

[0340]

[0341] [Chemistry 110]

[0342]

[0343] Specific examples of the onium salt represented by formula (A) include any combination of the above-mentioned anions and cations.

[0344] The onium salt represented by formula (A) can be synthesized by a known method. As an example, the case where L in formula (A) is a sulfonate bond is exemplified below, but the present invention is not limited thereto.

[0345] [Chemistry 111]

[0346]

[0347] In the formula, n1, n2, R1 , R 2 , R 3 and Z + Same as above. + It is lithium ion, sodium ion or potassium ion. - It is a halide ion or a methyl sulfate ion.

[0348] The first step is to obtain sulfonate (S-3) by reacting sulfonyl chloride (S-1) with hydroxysulfonate (S-2). The reaction can be carried out according to a common method, by sequentially or simultaneously adding sulfonyl chloride (S-1), hydroxysulfonate (S-2) and a base to a solvent, and preferably cooling or heating the reaction mixture as needed.

[0349] The solvents that can be used in the reaction of the first step include: ethers such as water, tetrahydrofuran (THF), diethyl ether, diisopropyl ether, di-n-butyl ether, and 1,4-dioxane; hydrocarbons such as n-hexane, n-heptane, benzene, toluene, and xylene; aprotic polar solvents such as acetonitrile, dimethyl sulfoxide (DMSO), and N,N-dimethylformamide (DMF); chlorine-based organic solvents such as dichloromethane, chloroform, and carbon tetrachloride, etc. These solvents can be appropriately selected and used depending on the reaction conditions, and can be used alone or in combination of two or more.

[0350] In addition, the base that can be used in the reaction of the first step includes, for example, amines such as ammonia, triethylamine, pyridine, collidine, collidine, N,N-dimethylaniline, etc.; hydroxides such as sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, etc.; carbonates such as potassium carbonate, sodium bicarbonate, etc. These bases may be used alone or in combination of two or more.

[0351] The second step is a step of obtaining an onium salt (A') by an ion exchange reaction between the sulfonate (S-3) and the onium salt (S-4). The sulfonate (S-3) may be isolated by a conventional aqueous work-up after the reaction in the first step, or may be used without any particular work-up after the reaction is stopped.

[0352] When using the separated sulfonate (S-3), the sulfonate (S-3) can be dissolved in water, THF, diethyl ether, diisopropyl ether, di-n-butyl ether, 1,4-dioxane and other ethers; hydrocarbons such as n-hexane, n-heptane, benzene, toluene, xylene; aprotic polar solvents such as acetonitrile, DMSO, DMF; chlorine-based organic solvents such as dichloromethane, chloroform, carbon tetrachloride, etc., and then mixed with the onium salt (S-4), and cooled or heated as needed to obtain a reaction mixture. Thereafter, the onium salt (A') can be obtained from the above reaction mixture by a conventional aqueous post-treatment. If necessary, it can also be purified by common methods such as distillation, recrystallization, chromatography, etc.

[0353] When the reaction of synthesizing sulfonate (S-3) is stopped without any post-treatment, the onium salt (S-4) can be added to the mixture obtained by stopping the synthesis reaction of sulfonate (S-3), and the mixture is cooled or heated as needed to obtain the onium salt (A'). At this time, ethers such as water, THF, diethyl ether, diisopropyl ether, di-n-butyl ether, 1,4-dioxane, etc.; hydrocarbons such as n-hexane, n-heptane, benzene, toluene, xylene, etc.; aprotic polar solvents such as acetonitrile, DMSO, DMF, etc.; chlorine-based organic solvents such as dichloromethane, chloroform, carbon tetrachloride, etc. can also be added as needed. The onium salt (A') can be obtained from the reaction mixture by a conventional aqueous post-treatment. If necessary, it can also be purified by common methods such as recrystallization and chromatography.

[0354] The onium salt represented by formula (A) has an onium salt structure of sulfonic acid not substituted by fluorine atoms, and thus can generate an acid of appropriate strength by irradiation with high-energy rays. - The α-position of the sulfonic acid produced is shielded by a bulky substituent, and the rotation of the bond axis of L connecting the bulky substituent at the α-position and the bulky substituent on another aromatic ring is suppressed due to steric hindrance, so that excessive acid diffusion of the produced acid can be suppressed. By utilizing these multiplication effects, the contrast between the exposed part and the unexposed part becomes good, and a pattern with small roughness can be formed even in fine pattern formation. By utilizing these effects, an acid with moderate acid strength and controlled acid diffusion can be generated in the resist film, so a pattern with good resolution and small LER can be obtained even in fine patterns, and a pattern with good rectangularity can be obtained by appropriate dissolution inhibition even in a negative resist composition using an alkaline developer.

[0355] In the chemically amplified negative resist composition of the present invention, the content of the onium salt represented by formula (A) is preferably 0.001 to 50 parts by mass, more preferably 0.01 to 40 parts by mass, based on 80 parts by mass of the base polymer (B) described later, from the viewpoint of sensitivity and acid diffusion inhibition effect.

[0356] The chemically amplified negative resist composition of the present invention may further contain an acid generator other than the onium salt represented by formula (A) (hereinafter also referred to as other acid generator) for the purpose of pattern shape correction, etc. The other acid generator may be an acid generator known to be used in a resist composition. The content of the other acid generator is preferably 0 to 40 parts by mass, and more preferably 0 to 30 parts by mass, relative to 80 parts by mass of the base polymer (B) described later, in view of sensitivity and acid diffusion inhibition effect. The other acid generator may be used alone or in combination of two or more.

[0357] [(B) Base polymer]

[0358] The base polymer of component (B) is a polymer (hereinafter referred to as polymer B) containing a repeating unit represented by the following formula (B1) (hereinafter referred to as repeating unit B1). Repeating unit B1 is a repeating unit that provides etching resistance, adhesion to the substrate, and solubility in an alkaline developer.

[0359] [Chemistry 112]

[0360]

[0361] In formula (B1), a1 is 0 or 1. a2 is an integer of 0 to 2, and when 0, it represents a benzene skeleton, when 1, it represents a naphthalene skeleton, and when 2, it represents an anthracene skeleton. a3 is an integer satisfying 0≤a3≤5+2(a2)-a4. a4 is an integer of 1 to 3. When a2 is 0, it is preferable that a3 is an integer of 0 to 3 and a4 is an integer of 1 to 3. When a2 is 1 or 2, it is preferable that a3 is an integer of 0 to 4 and a4 is an integer of 1 to 3.

[0362] In formula (B1), R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0363] In formula (B1), R 11 It is a halogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom. The saturated hydrocarbon group of the saturated hydrocarbon group, the saturated hydrocarbon oxy group, and the saturated hydrocarbon carbonyloxy group may be straight chain, branched, or cyclic. Specific examples thereof include: alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; and groups obtained by combining them. If the number of carbon atoms is below the upper limit, the solubility in the alkaline developer is good. When a3 is 2 or more, each R 11 They can be the same or different.

[0364] In formula (B1), A 1It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of -CH2- in the saturated alkylene group may be substituted by -O-. The saturated alkylene group may be linear, branched or cyclic, and specific examples thereof include: alkylene groups having 1 to 10 carbon atoms such as methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers; cyclic saturated alkylene groups having 3 to 10 carbon atoms such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining them. When the saturated alkylene group contains an ether bond, when a1 in formula (B1) is 1, it may be inserted at any position except between the carbon atom at the α position and the carbon atom at the β position relative to the ester oxygen atom. When a1 is 0, the atom bonded to the main chain is an etheric oxygen atom, and the second ether bond may be inserted at any position except between the carbon atom at the α position and the carbon atom at the β position relative to the etheric oxygen atom. In addition, if the carbon number of the saturated alkylene group is 10 or less, sufficient solubility in an alkaline developer can be obtained, which is more preferable.

[0365] a1 is 0 and A 1 In the case of a single bond, in other words, the aromatic ring is directly bonded to the main chain of the polymer (i.e., there is no linking group (-C(=O)-OA 1 -)), the repeating unit B1 preferably includes units derived from 3-hydroxystyrene, 4-hydroxystyrene, 5-hydroxy-2-vinylnaphthalene, 6-hydroxy-2-vinylnaphthalene, etc. The repeating unit represented by the following formula (B1-1) is particularly preferred.

[0366] [Chemistry 113]

[0367]

[0368] In the formula, R A and a4 are the same as above.

[0369] a1 is 1 (i.e., has -C(=O)-OA 1 - as a linking group), the following are preferred examples of repeating unit B1, but are not limited thereto. A Same as above.

[0370] [Chemistry 114]

[0371]

[0372] The repeating unit B1 may be used alone or in combination of two or more.

[0373] The polymer B may contain a repeating unit represented by the following formula (B2) (hereinafter, also referred to as repeating unit B2) (hereinafter, the polymer B further containing the repeating unit B2 is also referred to as polymer B').

[0374] [Chemistry 115]

[0375]

[0376] When the repeating unit B2 is irradiated with high-energy radiation, it will be reacted with the acid generated by the acid generator. 1 The repeating unit B2 causes a separation reaction and induces a crosslinking reaction between polymers and is insoluble in an alkaline developer. The negative-type reaction can be more effectively carried out by the repeating unit B2, thereby improving the resolution performance.

[0377] In formula (B2), b1 is 0 or 1. b2 is an integer of 0 to 2. b3 is an integer satisfying 0≤b3≤5+2(b2)-b4. b4 is an integer of 1 to 3.

[0378] In formula (B2), R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0379] In formula (B2), R 12 is a halogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom. The saturated hydrocarbon moiety of the saturated hydrocarbon group, saturated hydrocarbon oxy group, and saturated hydrocarbon carbonyloxy group may be straight chain, branched, or cyclic. Specific examples thereof include: alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, and their structural isomers; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; and groups obtained by combining these. When b3 is 2 or more, each R 12 They can be the same or different.

[0380] In formula (B2), R 13 and R 14 Each of R is independently a hydrogen atom, a saturated hydrocarbon group having 1 to 15 carbon atoms which may be substituted with a hydroxyl group or a saturated hydrocarbon oxy group, or an aryl group which may have a substituent. 13 and R 14 cannot be a hydrogen atom at the same time. 13 and R 14 They may also be bonded to each other and to the carbon atoms to which they are bonded to form a ring. 13 and R 14 Preferred examples include alkyl groups such as methyl, ethyl, propyl, butyl, and structural isomers thereof, and groups in which a part of hydrogen atoms thereof is substituted with a hydroxyl group or a saturated hydrocarbon oxy group.

[0381] In formula (B2), A 2 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of -CH2- of the saturated alkylene group may be substituted by -O-. The saturated alkylene group may be linear, branched or cyclic, and specific examples thereof include: methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers; cyclic saturated alkylene groups such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining them. When the saturated alkylene group contains an ether bond, when b1 in formula (B2) is 1, it may be inserted at any position except between the carbon atom at the α position and the carbon atom at the β position relative to the ester oxygen atom. When b1 is 0, the atom bonded to the main chain is an etheric oxygen atom, and the second ether bond may be inserted at any position except between the carbon atom at the α-position and the carbon atom at the β-position with respect to the etheric oxygen atom.

[0382] In formula (B2), W 1 It is a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aryl group which may have a substituent. The aforementioned aliphatic hydrocarbon group may be any of linear, branched, and cyclic, and specific examples thereof include: alkyl groups such as methyl, ethyl, propyl, and isopropyl; cyclic aliphatic hydrocarbon groups such as cyclopentyl, cyclohexyl, and adamantyl. Examples of the aforementioned aryl group include: phenyl, etc. In addition, a part of -CH2- of the aforementioned aliphatic hydrocarbon group may be substituted by -O-, -C(=O)-, -OC(=O)-, or -C(=O)-O-. In addition, the -CH2- of the aforementioned hydrocarbon group may be bonded to the oxygen atom in formula (B2). Examples of such substituted groups include: methylcarbonyl, etc.

[0383] The repeating unit B2 is preferably represented by the following formula (B2-1) or (B2-2).

[0384] [Chemistry 116]

[0385]

[0386] In the formula, b4, R A , R 13 and R 14 Same as above.

[0387] Preferred examples of repeating unit B2 include those shown below, but are not limited thereto. A As mentioned above, Me is methyl and Ac is acetyl.

[0388] [Chemistry 117]

[0389]

[0390] [Chemistry 118]

[0391]

[0392] [Chemistry 119]

[0393]

[0394] [Chemistry 120]

[0395]

[0396] [Chemistry 121]

[0397]

[0398] [Chemistry 122]

[0399]

[0400] [Chemistry 123]

[0401]

[0402] [Chemistry 124]

[0403]

[0404] [Chemistry 125]

[0405]

[0406] [Chemistry 126]

[0407]

[0408] [Chemistry 127]

[0409]

[0410] The repeating unit B2 may be used alone or in combination of two or more.

[0411] In order to improve etching resistance, polymers B and B' may also contain at least one selected from the repeating unit represented by the following formula (B3) (hereinafter also referred to as repeating unit B3), the repeating unit represented by the following formula (B4) (hereinafter also referred to as repeating unit B4) and the repeating unit represented by the following formula (B5) (hereinafter also referred to as repeating unit B5).

[0412] [Chemistry 128]

[0413]

[0414] In formulae (B3) and (B4), c and d are each independently an integer of 0 to 4.

[0415] In formula (B3) and (B4), R 21 and R 22 Each of R is independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group having 1 to 8 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom. The saturated hydrocarbon group, saturated hydrocarbon oxy group, and saturated hydrocarbon carbonyloxy group may be straight-chain, branched, or cyclic. When c is 2 or more, each R 21 They may be the same or different from each other. When d is 2 or more, each R 22 They can be the same or different.

[0416] In formula (B5), e1 is 0 or 1. e2 is an integer of 0 to 2, and when 0, it represents a benzene skeleton, when 1, it represents a naphthalene skeleton, and when 2, it represents an anthracene skeleton. e3 is an integer of 0 to 5. When e2 is 0, e3 is preferably an integer of 0 to 3, and when e2 is 1 or 2, e3 is preferably an integer of 0 to 4.

[0417] In formula (B5), R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

[0418] In formula (B5), R 23 is a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 20 carbon atoms, a saturated hydrocarbon oxy hydrocarbon group having 2 to 20 carbon atoms, a saturated hydrocarbon thio hydrocarbon group having 2 to 20 carbon atoms, a halogen atom, a nitro group, a cyano group, a saturated hydrocarbon sulfinyl group having 1 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl group having 1 to 20 carbon atoms. The saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyl oxy group, saturated hydrocarbon oxy hydrocarbon group, saturated hydrocarbon thio hydrocarbon group, saturated hydrocarbon sulfinyl group, and saturated hydrocarbon sulfonyl group may be straight-chain, branched, or cyclic. When e3 is 2 or more, each R 23 They can be the same or different.

[0419] R 23 Preferred are halogen atoms such as chlorine atoms, bromine atoms, and iodine atoms; saturated hydrocarbon groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclopentyl, cyclohexyl, and structural isomers thereof; and saturated hydrocarbon oxy groups such as methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, cyclopentyloxy, cyclohexyloxy, and structural isomers of their hydrocarbon moieties. Among them, methoxy and ethoxy are particularly useful.

[0420] Furthermore, the saturated hydrocarbon carbonyloxy group can be easily introduced by chemical modification even after the polymerization of the polymer, and can be used for fine adjustment of the solubility of the base polymer in the alkaline developer. Examples of the saturated hydrocarbon carbonyloxy group include methylcarbonyloxy, ethylcarbonyloxy, propylcarbonyloxy, butylcarbonyloxy, pentylcarbonyloxy, hexylcarbonyloxy, cyclopentylcarbonyloxy, cyclohexylcarbonyloxy, benzoyloxy, and structural isomers of their hydrocarbon parts. If the carbon number is 20 or less, the effect of controlling and adjusting the solubility of the base polymer in the alkaline developer (mainly the decreasing effect) can be adjusted to an appropriate range, and the generation of scum (development defects) can be suppressed.

[0421] Among the above-mentioned desirable substituents, particularly those which are easily prepared as monomers and can be used effectively include a chlorine atom, a bromine atom, an iodine atom, a methyl group, an ethyl group, a methoxy group and the like.

[0422] In formula (B5), A 3 is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of -CH2- in the saturated alkylene group may be substituted by -O-. The saturated alkylene group may be linear, branched or cyclic, and specific examples thereof include: alkylene groups having 1 to 10 carbon atoms, such as methylene, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, and their structural isomers; cyclic saturated alkylene groups having 3 to 10 carbon atoms, such as cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, and cyclohexanediyl; and groups obtained by combining them. When the saturated alkylene group contains an ether bond, when e1 in formula (B5) is 1, it may be inserted at any position except between the carbon atom at the α position and the carbon atom at the β position relative to the ester oxygen atom. When e1 is 0, the atom bonded to the main chain is an etheric oxygen atom, and the second ether bond may be inserted at any position except between the carbon atom at the α position and the carbon atom at the β position relative to the etheric oxygen atom. In addition, if the carbon number of the saturated alkylene group is 10 or less, sufficient solubility in an alkaline developer can be obtained, which is more preferable.

[0423] e1 is 0 and A 3 In the case of a single bond, in other words, the aromatic ring is directly bonded to the main chain of the polymer (i.e., there is no linking group (-C(=O)-OA 3 -)), preferable examples of the repeating unit B5 include units derived from styrene, 4-chlorostyrene, 4-methylstyrene, 4-methoxystyrene, 4-bromostyrene, 4-acetoxystyrene, 2-hydroxypropylstyrene, 2-vinylnaphthalene, 3-vinylnaphthalene and the like.

[0424] When e1 is 1 (i.e., having -C(=O)-OA 3- as a linking group), the following are preferred examples of repeating unit B5, but are not limited thereto. A Same as above.

[0425] [Chemistry 129]

[0426]

[0427] [Chemistry 130]

[0428]

[0429] When at least one of the repeating units B3 to B5 is used as a constituent unit of the polymer, the etching resistance of the aromatic ring is improved, and the etching resistance due to the addition of a ring structure to the main chain and the EB irradiation resistance during pattern inspection are improved.

[0430] The repeating units B3 to B5 may be used alone or in combination of two or more.

[0431] The polymer B' may further contain at least one selected from the repeating unit represented by the following formula (B6) (hereinafter also referred to as repeating unit B6), the repeating unit represented by the following formula (B7) (hereinafter also referred to as repeating unit B7), the repeating unit represented by the following formula (B8) (hereinafter also referred to as repeating unit B8), the repeating unit represented by the following formula (B9) (hereinafter also referred to as repeating unit B9), the repeating unit represented by the following formula (B10) (hereinafter also referred to as repeating unit B10), the repeating unit represented by the following formula (B11) (hereinafter also referred to as repeating unit B11), the repeating unit represented by the following formula (B12) (hereinafter also referred to as repeating unit B12) and the repeating unit represented by the following formula (B13) (hereinafter also referred to as repeating unit B13). In this case, acid diffusion can be effectively suppressed and resolution can be improved, and a pattern with reduced LER can be obtained.

[0432] [Chemistry 131]

[0433]

[0434] In formulas (B6) to (B13), R B are independently a hydrogen atom or a methyl group. 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 *-OY 11 -, *-C(=O)-OY 11 - or *-C(=O)-NH-Y 11 -, and Y 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.2 is a single bond or **-Y 21 -C(=O)-O-, and Y 21 Y is a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. 3 is a single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, *-OY 31 -, *-C(=O)-OY 31 - or *-C(=O)-NH-Y 31 -.Y 31 It is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, a phenylene group substituted with a trifluoromethyl group, or a group having 7 to 20 carbon atoms obtained by combining them, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. * is an atomic bond to a carbon atom of the main chain, and ** is an atomic bond to an oxygen atom in the formula. Y 4 is a single bond or a alkylene group having 1 to 30 carbon atoms which may contain a hetero atom. f1 and f2 are each independently 0 or 1, but in Y 4 When it is a single bond, f1 and f2 are 0.

[0435] In formula (B6) and (B10), Xa - It is a non-nucleophilic counter ion. - Examples of the non-nucleophilic counter ion represented by include those described in JP-A-2010-113209 and JP-A-2007-145797.

[0436] In formula (B7) and (B11), Y 2 Y 21 -C(=O)-O-, Y 21 The hydrocarbylene group which may contain a hetero atom may be exemplified by the following, but is not limited thereto.

[0437] [Chemistry 132]

[0438]

[0439] In the formula, the dotted lines are atomic bonds.

[0440] In formula (B7) and (B11), R HF is a hydrogen atom or a trifluoromethyl group. In repeating units B7 and B11, R HF Specific examples of a hydrogen atom include those described in Japanese Patent Application Laid-Open No. 2010-116550, HF Specific examples of the trifluoromethyl group include those described in Japanese Patent Application Laid-Open No. 2010-77404. Examples of the repeating units B8 and B12 include those described in Japanese Patent Application Laid-Open No. 2012-246265 and Japanese Patent Application Laid-Open No. 2012-246426.

[0441] Preferred examples of the anion of the monomer providing the repeating unit B9 or B13 include those shown below, but are not limited thereto.

[0442] [Chemistry 133]

[0443]

[0444] [Chemistry 134]

[0445]

[0446] In formulas (B6) to (B13), R 31 ~R 48 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 of the halogen atom and hydrocarbon group include those exemplified as R in the description of formula (cation-1) and (cation-2). ct1 ~R ct5 The same examples are given for the halogen atoms and hydrocarbon groups represented by the above. In addition, part or all of the hydrogen atoms of the above hydrocarbon groups may be substituted by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and part of the -CH2- of the above hydrocarbon groups may be substituted by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms, and as a result, hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sultone rings, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl groups, etc. may be contained.

[0447] Again, R 31 and R 32 They may also be bonded to each other and to the sulfur atom to which they are bonded to form a ring, and R 33 and R 34 , R 36 and R 37 , or R 39 and R 40 They may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded. The ring formed in this case can be exemplified as R in the description of formula (cation-1): ct1 and R ct2 The same example is true of the rings that can be formed by bonding to each other and to the sulfur atoms to which they are bonded.

[0448] Specific examples of the sulfonium cations of repeating units B7 to B9 include the same examples as those exemplified as the sulfonium cations represented by formula (cation-1). Specific examples of the iodonium cations of repeating units B11 to B13 include the same examples as those exemplified as the iodonium cations represented by formula (cation-2).

[0449] Repeating units B6 to B13 are units that generate acid due to irradiation with high-energy rays. It is believed that by including these units in the polymer, acid diffusion can be appropriately suppressed, and a pattern with reduced LER can be obtained. In addition, it is believed that by including these units in the polymer, the phenomenon that the acid evaporates from the exposed part and reattaches to the unexposed part during baking in a vacuum can be suppressed, and it is effective in reducing LER and reducing defects caused by suppressing undesirable negative-type reactions in the unexposed part.

[0450] The repeating units B6 to B13 may be used alone or in combination of two or more.

[0451] The polymers B and B' may contain a (meth)acrylate unit having a lactone structure or an adhesive group such as a hydroxyl group other than a phenolic hydroxyl group, or other repeating units in order to finely adjust the properties of the resist film.

[0452] Examples of the (meth)acrylate unit having an adhesion group include a repeating unit represented by the following formula (B14) (hereinafter also referred to as repeating unit B14), a repeating unit represented by the following formula (B15) (hereinafter also referred to as repeating unit B15), and a repeating unit represented by the following formula (B16) (hereinafter also referred to as repeating unit B16). These units do not exhibit acidity and can be used auxiliaryly as units for providing adhesion to a substrate or units for adjusting solubility.

[0453] [Chemistry 135]

[0454]

[0455] In formulas (B14) to (B16), R A R is independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. 51 is -O- or methylene. 52 is a hydrogen atom or a hydroxyl group. 53 is a saturated hydrocarbon group having 1 to 4 carbon atoms. g is an integer of 0 to 3.

[0456] In polymer B, the content of repeating unit B1 is preferably 30 to 95 mol%, and more preferably 50 to 85 mol%, in order to obtain a high contrast between the negative-type part and the non-irradiated part (the part not negative-typed) by high-energy ray irradiation for the purpose of obtaining high resolution. In addition, the content of repeating unit B2 is preferably 5 to 70 mol%, and more preferably 10 to 60 mol%, in order to obtain the effect of promoting the negative-type reaction. The content of repeating units B3 to B5 is preferably 0 to 30 mol%, and more preferably 3 to 20 mol%, in order to obtain the effect of improving etching resistance. In addition, other repeating units may also be contained at 0 to 30 mol%, and it is preferable to contain 0 to 20 mol%.

[0457] When polymer B' does not contain repeating units B6 to B13, the content of repeating unit B1 in polymer B' is preferably 25 to 95 mol%, preferably 40 to 85 mol%. The content of repeating units B3 to B5 is preferably 0 to 30 mol%, preferably 3 to 20 mol%. The content of repeating unit B2 is preferably 5 to 70 mol%, preferably 10 to 60 mol%. In addition, it may also contain other repeating units 0 to 30 mol%, preferably 0 to 20 mol%.

[0458] When polymer B' contains repeating units B6 to B13, the content of repeating unit B1 in polymer B' is preferably 25 to 94.5 mol%, preferably 36 to 85 mol%. The content of repeating units B3 to B5 is preferably 0 to 30 mol%, preferably 3 to 20 mol%. The content of repeating unit B2 is preferably 5 to 70 mol%, preferably 10 to 60 mol%. In addition, the total content of repeating units B1 to B5 is preferably 60 to 99.5 mol%. The content of repeating units B6 to B13 is preferably 0.5 to 20 mol%, preferably 1 to 10 mol%. In addition, it may also contain other repeating units 0 to 30 mol%, preferably 0 to 20 mol%.

[0459] In addition, of all the repeating units constituting the above-mentioned polymer, repeating units B1 to B5 preferably account for 60 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more, thereby reliably obtaining the necessary characteristics of the chemically amplified negative resist composition of the present invention.

[0460] In this case, the polymer B' preferably contains a repeating unit represented by the following formula (B1-1), a repeating unit represented by the following formula (B2-1) or (B2-2), and a repeating unit represented by the following formula (B7).

[0461] [Chemistry 136]

[0462]

[0463] In the formula, a4, b4, R A , R B , Y2 , R 13 , R 14 , R 33 , R 34 , R 35 and R HF Same as above.

[0464] When polymer B' is used as the base polymer (B), a polymer not containing repeating units B6 to B13 and a polymer containing repeating units B6 to B13 may be used in combination. In this case, the content of the polymer not containing repeating units B6 to B13 in the chemically amplified negative resist composition of the present invention is preferably 2 to 5000 parts by mass, more preferably 10 to 1000 parts by mass, relative to 100 parts by mass of the polymer containing repeating units B6 to B13.

[0465] When the chemically amplified negative resist composition is used for mask production, the most advanced generation of coating film thickness is 150 nm or less, preferably 100 nm or less. The dissolution rate of the base polymer constituting the aforementioned chemically amplified negative resist composition in an alkaline developer (e.g., a 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution) is generally preferably 80 nm / sec or less, and more preferably 50 nm / sec or less in the case of strong development treatment in order to further reduce defects caused by resist residues and to form fine patterns. In addition, for example, in the case of making LSI chips from wafers, when the chemically amplified negative resist composition of the present invention is used in EUV exposure treatment, it is often necessary to pattern fine lines such as 50 nm or less, so the coating film thickness is often adjusted to 100 nm or less, and because it is a thin film, the pattern may be degraded due to development, so the dissolution rate of the polymer used is preferably 80 nm / sec or less, and more preferably 50 nm / sec or less.

[0466] The above-mentioned polymer can be synthesized by copolymerizing each monomer protected by a protecting group as required by a known method, and then performing a deprotection reaction as required. The copolymerization reaction is not particularly limited, and is preferably free radical polymerization or anionic polymerization. For these methods, reference can be made to International Publication No. 2006 / 121096, Japanese Patent Publication No. 2008-102383, Japanese Patent Publication No. 2008-304590, and Japanese Patent Publication No. 2004-115630.

[0467] The weight average molecular weight (Mw) of the above-mentioned polymer is preferably 1000 to 50000, and more preferably 2000 to 20000. If Mw is 1000 or more, there is no concern that the top of the pattern becomes rounded, the resolution is reduced, and the LER deteriorates as is known in the past. On the other hand, if Mw is 50000 or less, there is no concern that the LER increases, especially when forming a pattern with a line width of 100 nm or less. In addition, Mw in the present invention is a polystyrene-converted measurement value obtained by gel permeation chromatography (GPC) using tetrahydrofuran (THF) or dimethylformamide (DMF) as a solvent.

[0468] The molecular weight distribution (Mw / Mn) of the polymer is preferably 1.0 to 2.0, preferably 1.0 to 1.8. When the distribution is narrow, foreign matter will not be generated on the pattern after development, and the pattern shape will not be deteriorated.

[0469] [(C) Cross-linking agent]

[0470] When the base polymer (B) does not contain the polymer B', the chemically amplified negative resist composition of the present invention preferably contains a crosslinking agent as the component (C). On the other hand, when the base polymer (B) contains the polymer B', it may not contain a crosslinking agent.

[0471] Specific examples of crosslinking agents that can be used in the present invention include epoxy compounds substituted with at least one group selected from hydroxymethyl, alkoxymethyl, and acyloxymethyl, melamine compounds, guanamine compounds, glycoluril compounds or urea compounds, isocyanate compounds, azide compounds, compounds containing double bonds such as alkenyloxy groups, etc. These can be used as additives or introduced as pendant groups in the side chains of polymers. In addition, compounds containing hydroxyl groups can also be used as crosslinking agents.

[0472] Examples of the epoxy compound include tris(2,3-epoxypropyl)isocyanurate, trimethylolmethane triglycidyl ether, trimethylolpropane triglycidyl ether, and triethylolethane triglycidyl ether.

[0473] Examples of the melamine compound include hexamethylolmelamine, hexamethoxymethylmelamine, compounds in which 1 to 6 methylol groups of hexamethylolmelamine are methoxymethylated, or mixtures thereof, and hexamethoxyethylmelamine, hexaacyloxymethylmelamine, compounds in which 1 to 6 methylol groups of hexamethylolmelamine are acyloxymethylated, or mixtures thereof.

[0474] Examples of the guanamine compound include tetramethylolguanamine, tetramethoxymethylguanamine, compounds in which 1 to 4 hydroxymethyl groups are methoxymethylated, such as tetramethylolguanamine, or mixtures thereof, and tetramethoxyethylguanamine, tetraacyloxyguanamine, compounds in which 1 to 4 hydroxymethyl groups are acyloxymethylated, such as tetramethylolguanamine, or mixtures thereof.

[0475] Examples of the glycoluril compound include tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, compounds in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, and compounds in which 1 to 4 hydroxymethyl groups of tetramethylol glycoluril are acyloxymethylated, or mixtures thereof.

[0476] Examples of the urea compound include tetramethylol urea, tetramethoxymethyl urea, compounds in which 1 to 4 methylol groups such as tetramethylol urea are methoxymethylated, or mixtures thereof, and tetramethoxyethyl urea.

[0477] Examples of the isocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and cyclohexane diisocyanate.

[0478] Examples of the azide compound include 1,1′-biphenyl-4,4′-bisazide, 4,4′-methylenebisazide, and 4,4′-oxybisazide.

[0479] Examples of the alkenyloxy group-containing compound include ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, 1,4-butanediol divinyl ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylolpropane trivinyl ether, hexanediol divinyl ether, 1,4-cyclohexanediol divinyl ether, pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, and trimethylolpropane trivinyl ether.

[0480] In the chemically amplified negative resist composition of the present invention, the content of the crosslinking agent (C) is preferably 0.1 to 50 parts by mass, and more preferably 1 to 30 parts by mass, relative to 80 parts by mass of the base polymer (B). If it is within the above range, the patterns will be connected and there is no concern about reduced resolution. The crosslinking agent (C) can be used alone or in combination of two or more.

[0481] [(D) Fluorine-containing polymer]

[0482] The chemically amplified negative resist composition of the present invention may contain a fluorine atom-containing polymer as component (D) in order to achieve high contrast, suppress chemical flare of acid during high-energy ray irradiation, shield acid from mixing from the antistatic film when the antistatic film material is applied to the resist film, and suppress unexpected and unwanted pattern degradation. The fluorine atom-containing polymer contains at least one selected from the group consisting of a repeating unit represented by the following formula (D1) (hereinafter also referred to as repeating unit D1), a repeating unit represented by the following formula (D2) (hereinafter also referred to as repeating unit D2), a repeating unit represented by the following formula (D3) (hereinafter also referred to as repeating unit D3), and a repeating unit represented by the following formula (D4) (hereinafter also referred to as repeating unit D4), and may further contain at least one selected from the group consisting of a repeating unit represented by the following formula (D5) (hereinafter also referred to as repeating unit D5) and a repeating unit represented by the following formula (D6) (hereinafter also referred to as repeating unit D6). The aforementioned fluorine-atom-containing polymer also has a surfactant function, so it can prevent insoluble matter that may be generated during the development process from re-attaching to the substrate, and thus also has an effect on development defects.

[0483] [Chemistry 137]

[0484]

[0485] In formulas (D1) to (D6), x is an integer of 1 to 3. y is an integer satisfying 0≤y≤5+2z-x. z is 0 or 1. k is an integer of 1 to 3. R C R is independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. D are each independently a hydrogen atom or a methyl group. 101 , R 102 , R 104 and R 105 R is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. 103 , R 106 , R 107 and R 108 are independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-labile group, and R 103 , R 106 , R 107 and R 108 When it is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group may be inserted between carbon-carbon bonds. 109 R is a hydrogen atom or a linear or branched hydrocarbon group having 1 to 5 carbon atoms, which may have a heteroatom-containing group inserted between carbon-carbon bonds. 110 It is a linear or branched hydrocarbon group having 1 to 5 carbon atoms, which may have a heteroatom-containing group inserted between carbon-carbon bonds. 111Z is a saturated hydrocarbon group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted by a fluorine atom, and a portion of the -CH2- in the saturated hydrocarbon group may be substituted by an ester bond or an ether bond. 1 Z is a (k+1)-valent hydrocarbon group having 1 to 20 carbon atoms or a (k+1)-valent fluorinated hydrocarbon group having 1 to 20 carbon atoms. 2 is a single bond, *-C(=O)-O- or *-C(=O)-NH-. * is an atomic bond to a carbon atom of the main chain. Z 3 is a single bond, -O-, *-C(=O)-OZ 31 -Z 32 - or *-C(=O)-NH-Z 31 -Z 32 -.Z 31 Z is a single bond or a saturated alkylene group having 1 to 10 carbon atoms. 32 is a single bond, ester bond, ether bond or sulfonamide bond. * is an atomic bond to a carbon atom of the main chain.

[0486] In formula (D1) and (D2), R 101 , R 102 , R 104 and R 105 The saturated hydrocarbon group having 1 to 10 carbon atoms represented by may be any of straight chain, branched, or cyclic, and specific examples thereof 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, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; and cyclic saturated hydrocarbon groups having 3 to 10 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, and norbornyl. Among them, saturated hydrocarbon groups having 1 to 6 carbon atoms are preferred.

[0487] In formulas (D1) to (D4), R 103 , R 106 , R 107 and R 108 The hydrocarbon group having 1 to 15 carbon atoms represented by the above may be any of straight chain, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 15 carbon atoms, alkenyl groups having 2 to 15 carbon atoms, alkynyl groups having 2 to 15 carbon atoms, and preferably alkyl groups having 1 to 15 carbon atoms. The above-mentioned alkyl groups include, in addition to the above-mentioned ones, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, and the like. In addition, the fluorinated hydrocarbon group includes groups in which a part or all of the hydrogen atoms bonded to the carbon atoms of the above-mentioned hydrocarbon groups are substituted with fluorine atoms.

[0488] In formula (D4), Z 1The (k+1)-valent hydrocarbon group having 1 to 20 carbon atoms represented by may be a group obtained by removing k hydrogen atoms from an alkyl group having 1 to 20 carbon atoms or a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. 1 Examples of the (k+1)-valent fluorinated hydrocarbon group having 1 to 20 carbon atoms represented by include groups in which at least one hydrogen atom in the aforementioned (k+1)-valent hydrocarbon group is substituted with a fluorine atom.

[0489] Specific examples of repeating units D1 to D4 include those shown below, but are not limited thereto. C Same as above.

[0490] [Chemistry 138]

[0491]

[0492] [Chemistry 139]

[0493]

[0494] [Chemistry 140]

[0495]

[0496] In formula (D5), R 109 and R 110 Examples of the hydrocarbon group having 1 to 5 carbon atoms represented by alkyl, alkenyl, alkynyl, etc. are listed, and alkyl is preferred. Examples of the aforementioned alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, etc. In addition, a group containing a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom may be inserted between the carbon-carbon bonds of the aforementioned hydrocarbon group.

[0497] In formula (D5), -OR 109 Preferably, it is a hydrophilic group. 109 Preferred are hydrogen atoms, alkyl groups having 1 to 5 carbon atoms in which an oxygen atom is inserted between carbon-carbon bonds, and the like.

[0498] In formula (D5), Z 2 It is preferably *-C(=O)-O- or *-C(=O)-NH-. D Preferably, it is methyl. 2 The presence of a carbonyl group in the antistatic film improves the capture ability of the acid from the antistatic film. D If it is a methyl group, it will become a hard polymer with a higher glass transition temperature (Tg), so the diffusion of acid will be suppressed. As a result, the stability of the resist film over time will be good, and the resolution and pattern shape will not deteriorate.

[0499] The repeating unit D5 may be exemplified by the following, but is not limited thereto. D Same as above.

[0500] [Chemistry 141]

[0501]

[0502] [Chemistry 142]

[0503]

[0504] In formula (D6), Z 3 The saturated alkylene group having 1 to 10 carbon atoms represented by the alkylene group may be straight-chain, branched or cyclic, and specific examples thereof include methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, 1,1-dimethylethane-1,2-diyl and the like.

[0505] In formula (D6), R 111 The saturated hydrocarbon group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted by a fluorine atom may be straight-chain, branched or cyclic. Specific examples thereof include an alkyl group having 1 to 20 carbon atoms or a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in which at least one hydrogen atom is substituted by a fluorine atom.

[0506] The repeating unit D6 may be exemplified by the following, but is not limited thereto. D Same as above.

[0507] [Chemistry 143]

[0508]

[0509] [Chemistry 144]

[0510]

[0511] [Chemistry 145]

[0512]

[0513] [Chemistry 146]

[0514]

[0515] The content of repeating units D1 to D4 is preferably 15 to 95 mol %, more preferably 20 to 85 mol %, of all repeating units of the aforementioned fluorine-containing polymer. The content of repeating units D5 and / or D6 is preferably 5 to 85 mol %, more preferably 15 to 80 mol % of all repeating units of the aforementioned fluorine-containing polymer. Repeating units D1 to D6 may be used alone or in combination of two or more.

[0516] The aforementioned fluorine-containing polymer may also contain other repeating units other than the aforementioned repeating units. Such repeating units may include those described in paragraphs

[0046] to

[0078] of Japanese Patent Publication No. 2014-177407. When the aforementioned fluorine-containing polymer contains other repeating units, the content thereof is preferably 50 mol% or less in all the repeating units of the aforementioned fluorine-containing polymer.

[0517] The fluorine-containing polymer can be synthesized by copolymerizing monomers protected by protective groups as required by known methods, and then performing a deprotection reaction as required. The copolymerization reaction is not particularly limited, and is preferably free radical polymerization or anionic polymerization. For these methods, reference can be made to Japanese Patent Publication No. 2004-115630.

[0518] The Mw of the fluorine-containing polymer is preferably 2000 to 50000, and more preferably 3000 to 20000. If the Mw is less than 2000, the diffusion of the acid may be promoted, the resolution may be degraded, and the stability over time may be impaired. If the Mw is too large, the solubility in the solvent may be reduced, and coating defects may occur. In addition, the Mw / Mn of the fluorine-containing polymer is preferably 1.0 to 2.2, and more preferably 1.0 to 1.7.

[0519] When the chemically amplified negative resist composition of the present invention contains a fluorine-containing polymer (D), its content is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and even more preferably 0.5 to 10 parts by mass relative to 80 parts by mass of the base polymer (B). The fluorine-containing polymer (D) may be used alone or in combination of two or more.

[0520] [(E) Quencher]

[0521] The chemically amplified negative resist composition of the present invention preferably contains a quencher as component (E). In addition, the quencher in the present invention refers to a material that traps the acid generated by the photoacid generator in the chemically amplified resist composition to prevent it from diffusing to the unexposed part and is used to form a desired pattern.

[0522] The quencher may be a known basic compound. The known basic compound may be a primary, secondary, or tertiary aliphatic amine, a mixed amine, an aromatic amine, a heterocyclic amine, a nitrogen-containing compound having a carboxyl group, a nitrogen-containing compound having a sulfonyl group, a nitrogen-containing compound having a hydroxyl group, a nitrogen-containing compound having a hydroxyphenyl group, an alcoholic nitrogen-containing compound, an amide, an imide, a carbamate, etc. In particular, the primary, secondary, or tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Application Laid-Open No. 2008-111103 are preferred, and the amine compounds having a hydroxyl group, an ether bond, an ester bond, a lactone ring, a cyano group, a sulfonate bond, or the compounds having a carbamate group described in Japanese Patent No. 3790649 are particularly preferred. Preferred examples include tris[2-(methoxymethoxy)ethyl]amine, tris[2-(methoxymethoxy)ethyl]amine-N-oxide, dibutylaminobenzoic acid, morpholine derivatives, imidazole derivatives, etc. By adding such a basic compound, for example, the diffusion rate of the acid in the resist film can be further suppressed or the shape can be corrected.

[0523] In addition, the quencher may be an onium salt such as a sulfonium salt, an iodonium salt, or an ammonium salt of a carboxylic acid whose α-position is not fluorinated as described in Japanese Patent Application Laid-Open No. 2008-158339. A sulfonic acid, an imidic acid, or a methylated acid whose α-position is fluorinated is necessary to deprotect an acid-labile group, and a carboxylic acid whose α-position is not fluorinated is released by salt exchange with an onium salt whose α-position is not fluorinated. A carboxylic acid whose α-position is not fluorinated hardly causes a deprotection reaction, and thus functions as a quencher.

[0524] Examples of the onium salt of carboxylic acid in which the α-position is not fluorinated include those represented by the following formula (E1).

[0525] [Chemistry 147]

[0526] R 201 -CO2 - Mq A + (E1)

[0527] In formula (E1), R 201 It is a hydrocarbon group having 1 to 40 carbon atoms which may contain a hydrogen atom or a hetero atom, but excludes those in which the hydrogen atom bonded to the carbon atom at the α-position of the carboxyl group is substituted by a fluorine atom or a fluoroalkyl group.

[0528] R 201The hydrocarbon group 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, 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.

[0529] 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, and as a result, it may contain hydroxyl groups, cyano groups, carbonyl groups, ether bonds, thioether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sultone rings, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl groups, and the like. Examples of the heteroatom-containing hydrocarbon group 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; aryl pendant oxyalkyl 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.

[0530] In formula (E1), Mq A +It is an onium cation. The onium cation is preferably a sulfonium cation, an iodonium cation or an ammonium cation, and is more preferably a sulfonium cation or an iodonium cation. Specific examples of the sulfonium cation include the same examples as those exemplified as the sulfonium cation represented by formula (cation-1). Specific examples of the iodonium cation include the same examples as those exemplified as the iodonium cation represented by formula (cation-2).

[0531] Examples of the anion of the onium salt represented by the formula (E1) include the following, but are not limited thereto.

[0532] [Chemistry 148]

[0533]

[0534] [Chemistry 149]

[0535]

[0536] [Chemistry 150]

[0537]

[0538] As the quencher, a sulfonium salt of a carboxylic acid containing an iodinated benzene ring represented by the following formula (E2) can also be preferably used.

[0539] [Chemistry 151]

[0540]

[0541] In formula (E2), s is an integer of 1 to 5. t is an integer of 0 to 3. However, 1≤s+t≤5. u is an integer of 1 to 3.

[0542] In formula (E2), R 211 is a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, a nitro group, a cyano group, a saturated hydrocarbon group 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, a saturated hydrocarbon sulfonyloxy group having 1 to 4 carbon atoms, -N(R 211A )-C(=O)-R 211B or -N(R 211A )-C(=O)-OR 211B , and part or all of the hydrogen atoms of the saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyl oxy group or saturated hydrocarbon sulfonyl oxy group may be substituted by halogen atoms. 211A is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. 211B is a saturated hydrocarbon group having 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group having 2 to 8 carbon atoms. When t and / or u is 2 or more, each R 211 They can be the same or different.

[0543] In formula (E2), L11 It is a single bond or a (u+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 carbonyl oxy group, and saturated hydrocarbon sulfonyl oxy group may be straight-chain, branched, or cyclic.

[0544] In formula (E2), R 212 , R 213 and R 214 Each independently represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be any of linear, branched, and cyclic. Specific examples thereof include: alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, aralkyl groups having 7 to 20 carbon atoms, and the like. Furthermore, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted by a hydroxyl group, a carboxyl group, a halogen atom, an oxo group, a cyano group, a nitro group, a sultone ring, a sulfonium group, or a group containing a sulfonium salt, and a part of the -CH2- of the aforementioned hydrocarbon group may be substituted by an ether bond, an ester bond, a carbonyl group, an amide bond, a carbonate bond, or a sulfonate bond. Furthermore, R 212 and R 213 They may also bond to each other and to the sulfur atom to which they are bonded to form a ring.

[0545] Specific examples of the compound represented by formula (E2) include those described in Japanese Patent Application Laid-Open No. 2017-219836. The compound represented by formula (E2) has a high sensitization effect due to high absorption and also has a high acid diffusion control effect.

[0546] As the quencher, a nitrogen atom-containing carboxylate type compound represented by the following formula (E3) can also be used.

[0547] [Chemistry 152]

[0548]

[0549] In formula (E3), R 221 ~R 224 are independently a hydrogen atom, -L 12 -CO2 - , or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. 221 With R 222 , R 222 With R 223 , or R 223 With R 224 They may also bond to each other and to the carbon atoms to which they are bonded to form a ring. 12 R is a single bond or a alkylene group having 1 to 20 carbon atoms which may contain a hetero atom. 225It is a hydrocarbon group having 1 to 20 carbon atoms which may contain a hydrogen atom or a hetero atom.

[0550] In formula (E3), ring R r is a ring having 2 to 6 carbon atoms including the carbon atoms and nitrogen atoms in the formula, and part or all of the hydrogen atoms bonded to the carbon atoms in the ring may be replaced by a hydrocarbon group having 1 to 20 carbon atoms, or -L 12 -CO2 - The ring may be substituted with a -CH2- radical, and a part of the -CH2- radical of the ring may be substituted with a sulfur atom, an oxygen atom or a nitrogen atom. The aforementioned ring may be an alicyclic ring or an aromatic ring, and preferably a 5-membered ring or a 6-membered ring. Specific examples thereof include: a pyridine ring, a pyrrole ring, a pyrrolidine ring, a piperidine ring, a pyrazole ring, an imidazoline ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, an imidazoline ring, an oxazole ring, a thiazole ring, a morpholine ring, a thiazine ring, a triazole ring, and the like.

[0551] The carboxylic acid onium salt represented by formula (E3) has at least one -L 12 -CO2 - That is, R 221 ~R 224 At least one of them is -L 12 -CO2 - , and / or is bonded to ring R r At least one of the hydrogen atoms of a carbon atom is replaced by -L 12 -CO2 - Replacer.

[0552] In formula (E3), Mq B + It is a sulfonium cation, an iodonium cation or an ammonium cation, preferably a sulfonium cation. Specific examples of the sulfonium cation include the same examples as those exemplified as the sulfonium cation represented by the formula (cation-1).

[0553] Examples of the anion of the compound represented by formula (E3) include the following, but are not limited thereto.

[0554] [Chemistry 153]

[0555]

[0556] [Chemistry 154]

[0557]

[0558] [Chemistry 155]

[0559]

[0560] [Chemistry 156]

[0561]

[0562] [Chemistry 157]

[0563]

[0564] [Chemistry 158]

[0565]

[0566] Furthermore, a weakly acidic betaine-type compound may be used as the quencher. Specific examples thereof include those shown below, but are not limited thereto.

[0567] [Chemistry 159]

[0568]

[0569] The aforementioned quencher may further include a polymer quencher described in Japanese Patent Application Publication No. 2008-239918. The polymer quencher improves the rectangularity of the resist pattern by being aligned on the surface of the resist film. The polymer quencher also has the effect of preventing film loss and doming of the pattern when a protective film for immersion exposure is used.

[0570] When the chemically amplified negative resist composition of the present invention contains (E) a quencher, its content is preferably 0 to 50 parts by mass, more preferably 0.1 to 40 parts by mass, relative to 80 parts by mass of the base polymer (B). The (E) quencher may be used alone or in combination of two or more.

[0571] When the chemically amplified negative resist composition of the present invention contains a photoacid generator as component (A) and a quencher as component (E), the content ratio of the photoacid generator to the quencher ((A) / (E)) is preferably less than 6, more preferably less than 5, and even more preferably less than 4 in terms of mass ratio. When the content ratio of the photoacid generator to the quencher contained in the chemically amplified negative resist composition is within the above range, acid diffusion can be sufficiently suppressed, and excellent resolution and dimensional uniformity can be obtained.

[0572] [(F) Organic solvent]

[0573] The chemically amplified negative resist composition of the present invention may also contain an organic solvent as the (F) component. The aforementioned organic solvent is not particularly limited as long as it can dissolve each component. Such organic solvents include, for example, 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; propylene glycol monomethyl ether (PGME), ethylene glycol monomethyl ether (PGME), and ethylene glycol monomethyl ether (PGME). Ethers such as 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 (PGMEA), propylene glycol monoethyl ether acetate, ethyl lactate (EL), ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monotert-butyl ether acetate; lactones such as γ-butyrolactone; mixed solvents thereof, etc.

[0574] Among these organic solvents, 1-ethoxy-2-propanol, PGMEA, PGME, cyclohexanone, EL, γ-butyrolactone, and a mixed solvent thereof are preferred.

[0575] When the chemically amplified negative resist composition of the present invention contains (F) an organic solvent, its content is preferably 200 to 10,000 parts by mass, more preferably 400 to 6,000 parts by mass, relative to 80 parts by mass of the base polymer (B). The organic solvent (F) may be used alone or in combination of two or more.

[0576] [(G) Surfactant]

[0577] The chemically amplified negative resist composition of the present invention may also contain a conventional surfactant in order to improve the coating properties on the substrate. Examples of the aforementioned surfactant include PF-636 (manufactured by OMNOVA SOLUTIONS), FC-4430 (manufactured by 3M Company), and many examples are also recorded in Japanese Patent Gazette No. 2004-115630. There are many known surfactants, which can be selected as references. When the chemically amplified negative resist composition of the present invention contains a (G) surfactant, its content is preferably 0 to 5 parts by mass relative to 80 parts by mass of the (B) base polymer. The (G) surfactant may be used alone or in combination of two or more.

[0578] [Resist pattern forming method]

[0579] The resist pattern forming method of the present invention comprises the following steps: forming a resist film on a substrate using the aforementioned chemically amplified negative resist composition, irradiating the aforementioned resist film with a pattern using high-energy rays (i.e., exposing the aforementioned resist film with high-energy rays), and developing the resist film that has been irradiated with the aforementioned pattern using an alkaline developer.

[0580] The aforementioned substrate may be, for example, a substrate for integrated circuit manufacturing (Si, SiO, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflection film, etc.), or a substrate for transmissive or reflective mask circuit manufacturing (Cr, CrO, CrON, MoSi2, Si, SiO, SiO2, SiON, SiONC, CoTa, NiTa, TaBN, SnO2, etc.). On the aforementioned substrate, the aforementioned chemically amplified negative resist composition is applied by a spin coating method to a film thickness of 0.03 to 2 μm, and the composition is pre-baked on a hot plate preferably at 60 to 150° C. for 1 to 20 minutes, and more preferably at 80 to 140° C. for 1 to 10 minutes, to form a resist film.

[0581] Then, the resist film is exposed to a pattern using high-energy radiation. Examples of the high-energy radiation include ultraviolet radiation, extreme ultraviolet radiation, excimer laser (KrF, ArF, etc.), EUV, X-rays, gamma rays, synchrotron radiation, EB, etc. In the present invention, EUV or EB is preferably used for exposure.

[0582] When ultraviolet rays, extreme ultraviolet rays, excimer lasers, EUV, X-rays, gamma rays or synchrotron radiation are used as the high energy rays, a mask for forming a target pattern is used, and the exposure dose is preferably 1 to 500 mJ / cm 2 More preferably, it is 10 to 400 mJ / cm 2 When EB is used, the exposure dose is preferably 1 to 500 μC / cm2 in order to form the target pattern. 2 More preferably, it is 10 to 400 μC / cm 2 way of irradiation.

[0583] Exposure can be performed by a normal exposure method or, depending on the situation, by a wetting method in which the mask and the resist film are wetted. In this case, a water-insoluble protective film can also be used.

[0584] Then, a post-exposure bake (PEB) is performed on a hot plate at preferably 60-150° C. for 1-20 minutes, and more preferably 80-140° C. for 1-10 minutes.

[0585] Thereafter, a developer containing 0.1 to 5% by mass and preferably 2 to 3% by mass of an alkaline aqueous solution of TMAH or the like is used, and development is performed for preferably 0.1 to 3 minutes and more preferably 0.5 to 2 minutes by a common method such as a dip method, a puddle method, or a spray method to form a desired pattern on the substrate.

[0586] In addition, the chemically amplified negative resist composition of the present invention is particularly useful because it can form patterns with good resolution and low LER. Furthermore, since it is difficult to obtain the adhesion of the resist pattern, the chemically amplified negative resist composition of the present invention is particularly useful for pattern formation on substrates having materials on the surface that are prone to pattern peeling and pattern collapse. Such substrates include: substrates having a sputtered film of metallic chromium or a chromium compound containing one or more light elements selected from oxygen, nitrogen and carbon on the outermost layer; substrates containing SiO, SiO x , tantalum compounds, molybdenum compounds, cobalt compounds, nickel compounds, tungsten compounds, tin compounds, etc. The chemically amplified negative resist composition of the present invention is particularly useful for pattern formation using a blank photomask as a substrate. In this case, the blank photomask can be either a transmissive type or a reflective type.

[0587] Regarding the transmission type blank photomask, the blank photomask having a light shielding film made of a chromium-based material may be a blank photomask for a binary mask or a blank photomask for a phase shift mask. In the case of a blank photomask for a binary mask, the blank photomask may have an anti-reflection layer and a light shielding layer made of a chromium-based material as the light shielding film, or the anti-reflection film on the surface side may be entirely made of a chromium-based material, or only the more surface side of the anti-reflection film on the surface side may be made of a chromium-based material, and the remaining portion may be made of, for example, a silicon-based compound material that may also contain a transition metal. In addition, in the case of a blank photomask for a phase shift mask, a blank photomask for a phase shift mask having a chromium-based light shielding film on the phase shift film may be used as an object.

[0588] The aforementioned blank photomask having a chromium-based material as the outermost layer is already well known as the current technology as exemplified in Japanese Patent Publication No. 2008-26500, Japanese Patent Publication No. 2007-302873 or therein, and a detailed description thereof is omitted. For example, when a shading film having an anti-reflection layer and a shading layer is formed using a chromium-based material, a film structure as described below can be used.

[0589] When a light-shielding film having an anti-reflection layer and a light-shielding layer is formed using a chromium-based material, the layer structure may be a layer structure in which an anti-reflection layer and a light-shielding layer are stacked in order from the surface layer side, or an anti-reflection layer, a light-shielding layer, and an anti-reflection layer are stacked in order. In addition, the anti-reflection layer and the light-shielding layer may be a plurality of layers, and the layers with different compositions may have a discontinuous change in composition or a continuous change in composition. The chromium-based material used may be metal chromium and a material containing light elements such as oxygen, nitrogen, and carbon in metal chromium. Specifically, metal chromium, chromium oxide, chromium nitride, chromium carbide, chromium nitride oxide, chromium carbide oxide, chromium carbide nitride, chromium carbide oxide, chromium carbide nitride, chromium carbide oxide, and chromium carbide nitride.

[0590] Furthermore, the reflective blank mask includes: a substrate, and a multilayer reflective film formed on one main surface (surface on the outer surface side) of the substrate, specifically, a multilayer reflective film that reflects exposure light such as EUV light, and an absorber film formed on the multilayer reflective film, specifically, an absorber film that absorbs exposure light such as EUV light and reduces reflectivity. A reflective mask (reflective mask for EUV) having an absorber pattern (absorber film pattern) formed by patterning the absorber film is manufactured from the reflective blank mask (reflective blank mask for EUV). The wavelength of EUV light used for EUV lithography is 13 to 14 nm, usually light with a wavelength of about 13.5 nm.

[0591] The multilayer reflective film is usually preferably provided in contact with one of the main surfaces of the substrate, but a base film may be provided between the substrate and the multilayer reflective film as long as the effect of the present invention is not impaired. The absorber film may be formed in contact with the multilayer reflective film, or a protective film (a protective film of the multilayer reflective film) may be provided between the multilayer reflective film and the absorber film and preferably in contact with the multilayer reflective film, and more preferably a protective film (a protective film of the multilayer reflective film) is provided in contact with the multilayer reflective film and the absorber film. The protective film may be used to protect the multilayer reflective film during processing such as cleaning and correction. Furthermore, the protective film may preferably have the function of protecting the multilayer reflective film and preventing oxidation of the multilayer reflective film when the absorber film is patterned by etching. On the other hand, a conductive film used for electrostatically clamping the reflective mask in the exposure device may also be provided under the other main surface (the surface on the inner surface side) which is the opposite side of one of the main surfaces of the substrate and preferably in contact with the other main surface. In addition, here, one of the main surfaces of the substrate is defined as the surface on the outer surface side and the upper side, and the other main surface is defined as the surface on the inner surface side and the lower side, but the outer surface and the inner surface and the upper and lower sides of the two are defined for the convenience of explanation, and the one main surface and the other main surface can be any of the two main surfaces (film forming surfaces) in the substrate, and the outer surface and the inner surface and the upper and lower sides can be replaced with each other. More specifically, it can be formed using Japanese Patent Publication No. 2021-139970 or a method as exemplified in the current technology.

[0592] According to the resist pattern forming method of the present invention, even when using a substrate (such as a transmission or reflection type blank mask) whose outermost surface is made of a material that is easily affected by the shape of the resist pattern, such as a material containing chromium, silicon or tantalum, a pattern with extremely high resolution, small LER, excellent rectangularity and excellent pattern fidelity can still be obtained.

[0593] Example

[0594] Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0595] The structures of polymers P-1 to P-30 used in the resist composition are shown in the following Table 1. Mw is a polystyrene-equivalent measurement value obtained by GPC using THF or DMF as a solvent.

[0596] [Table 1]

[0597]

[0598]

[0599] In Table 1, the structure of each unit is as follows.

[0600] [Chemistry 160]

[0601]

[0602] [Chemistry 161]

[0603]

[0604] [Chemistry 162]

[0605]

[0606] [Chemistry 163]

[0607]

[0608] [Chemistry 164]

[0609]

[0610] [1] Preparation of chemically amplified negative resist composition

[0611] [Examples 1-1 to 1-54, Comparative Examples 1-1 to 1-10]

[0612] The components shown in the following Tables 2 to 4 are dissolved in an organic solvent, and the obtained solutions are filtered through a UPE filter and / or a nylon filter selected from 10 nm, 5 nm, 3 nm and 1 nm in size, thereby obtaining a chemically amplified negative resist composition (R-1 to R-54, CR-1 to CR-10). In addition, the aforementioned organic solvent is a mixed solvent of 790 parts by mass of PGMEA, 1580 parts by mass of EL and 1580 parts by mass of PGME. In addition, in a part of the composition, a fluorine-containing polymer (polymer FP-1 to FP-5) as an additive, tetramethoxymethyl glycoluril (TMGU) as a cross-linking agent, and PF-636 (manufactured by OMNOVA SOLUTIONS) as a surfactant are added.

[0613] [Table 2]

[0614]

[0615]

[0616] [Table 3]

[0617]

[0618]

[0619] [Table 4]

[0620]

[0621]

[0622] In Tables 2 to 4, the photoacid generators PAG-1 to PAG-9, the comparative photoacid generators cPAG-1 to cPAG-4, the quenchers Q-1 to Q-4, and the fluorine-containing polymers FP-1 to FP-5 are as follows.

[0623] [Chemistry 165]

[0624]

[0625] [Chemistry 166]

[0626]

[0627] [Chemistry 167]

[0628]

[0629] [Chemistry 168]

[0630]

[0631] [Chemistry 169]

[0632]

[0633] [2]EB Lithography Evaluation

[0634] [Examples 2-1 to 2-54, Comparative Examples 2-1 to 2-10]

[0635] Each chemically amplified negative resist composition (R-1 to R-54, CR-1 to CR-10) was spin-coated on a 152 mm square blank mask with a silicon oxide film on the outermost surface treated with hexamethyldisilazane (HMDS) vapor prime using ACT-M (Tokyo Electron Co., Ltd.), and pre-baked on a hot plate at 110°C for 600 seconds to obtain a resist film with a film thickness of 80 nm. The film thickness of the obtained resist film was measured using an optical measuring instrument NANOSPEC (Nanometrics). The measurement was performed at 81 locations within the surface of the blank substrate excluding the outer edge portion from the periphery of the blank substrate to the inner 10 mm, and the average film thickness and the film thickness range were calculated.

[0636] Exposure was performed using an electron beam exposure apparatus (EBM-5000plus manufactured by NuFlare Technology Co., Ltd., accelerating voltage 50 kV), PEB was applied at 120° C. for 600 seconds, and development was performed with a 2.38 mass % TMAH aqueous solution to obtain a negative pattern.

[0637] The obtained resist pattern was evaluated as follows. The obtained blank mask with pattern was observed using an overhead SEM (scanning electron microscope), and the exposure amount at which a 1:1 line and space (LS) of 200 nm was resolved at 1:1 was defined as the optimum exposure amount (μC / cm 2 ), and the minimum size at which 200nm LS can be resolved at an exposure of 1:1 is defined as the resolution (limit resolution). For the 200nm LS pattern obtained by irradiation with the optimal exposure, 80-point edge detection is performed on each of the 32 edges of the 200nm LS pattern using SEM, and the 3 times value (3σ) of its deviation (standard deviation, σ) is calculated and defined as LER (nm). The shape of the pattern is visually determined to be rectangular. In addition, for the evaluation of pattern fidelity (Fidelity), the area loss (Area loss) value (%) of one corner of the dot pattern is calculated when a square dot pattern with a density of 36% and a size of 120nm is configured. The smaller the value, the better the rectangularity of the dot shape. The results are shown in Tables 5 to 7.

[0638] [Table 5]

[0639]

[0640]

[0641] [Table 6]

[0642]

[0643]

[0644] [Table 7]

[0645]

[0646] The chemically amplified negative resist compositions (R-1 to R-54) of the present invention all exhibit good resolution, LER, pattern rectangularity and pattern fidelity. On the other hand, the comparative resist compositions (CR-1 to CR-10) have insufficiently designed acid generators and have insufficient performance in terms of resolution, LER and pattern rectangularity.

[0647] The resist pattern forming method using the chemically amplified negative resist composition of the present invention is useful in the manufacture of semiconductor devices, particularly in optical lithography during the processing of a transmission type or reflection type blank photomask.

Claims

1. A chemically amplified negative resist composition comprising: (A) a photoacid generator composed of an onium salt represented by the following formula (A), and (B) a base polymer comprising a polymer containing a repeating unit represented by the following formula (B1); In the formula, n1 is an integer of 0 to 2; n2 is an integer of 2 to 5 when n1=0, an integer of 2 to 7 when n1=1, and an integer of 2 to 9 when n1=2; L is a single bond, an ether bond, an ester bond, a sulfonate bond, a carbonate bond or a carbamate bond; R 1 and R 2 are independently hydrogen atoms or branched or cyclic hydrocarbon groups having 3 to 20 carbon atoms which may contain heteroatoms, but not all of them are hydrogen atoms; and R 1 With R 2 They can also bond to each other and to the carbon atoms to which they are bonded to form rings; R 3 are each independently an iodine atom or a branched or cyclic hydrocarbon group having 3 to 20 carbon atoms which may contain a hetero atom, and at least one R 3 Bonded to the carbon atom adjacent to the carbon atom to which L is bonded; Z + is an onium cation; In the formula, a1 is 0 or 1; a2 is an integer from 0 to 2; a3 is an integer satisfying 0≤a3≤5+2(a2)-a4; a4 is an integer from 1 to 3; R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; R 11 is a halogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom; A 1 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of the -CH2- of the saturated alkylene group may be substituted by -O-.

2. The chemically amplified negative resist composition according to claim 1, wherein: Component (A) is an onium salt represented by the following formula (A1); In the formula, L, R 1 , R 2 , R 3 and Z + Same as above; n3 is an integer from 1 to 4.

3. The chemically amplified negative resist composition according to claim 2, wherein: Component (A) is an onium salt represented by the following formula (A2); In the formula, n3, R 1 , R 2 , R 3 and Z + Same as above.

4. The chemically amplified negative resist composition according to claim 1, wherein: Z + It is a sulfonium cation represented by the following formula (cation-1) or an iodonium cation represented by the following formula (cation-2); In the formula, R ct1 ~R ct5 are independently a halogen atom or a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom; and R ct1 and R ct2 They may also bond to each other and to the sulfur atom to which they are bonded to form a ring.

5. The chemically amplified negative resist composition according to claim 1, wherein: The polymer further contains a repeating unit represented by the following formula (B2); In the formula, b1 is 0 or 1; b2 is an integer from 0 to 2; b3 is an integer satisfying 0≤b3≤5+2(b2)-b4; b4 is an integer from 1 to 3; R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; R 12 is a halogen atom, a saturated hydrocarbon group having 1 to 6 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom; R 13 and R 14 are each independently a hydrogen atom, a saturated hydrocarbon group having 1 to 15 carbon atoms which may be substituted with a hydroxyl group or a saturated hydrocarbon oxy group, or an aryl group which may have a substituent; however, R 13 and R 14 cannot be a hydrogen atom at the same time; and R 13 and R 14 They can also bond to each other and to the carbon atoms to which they are bonded to form rings; A 2 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a portion of -CH2- in the saturated alkylene group may be substituted by -O-; W 1 It is a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aryl group which may have a substituent.

6. The chemically amplified negative resist composition according to claim 1, wherein: The polymer further contains at least one selected from the group consisting of a repeating unit represented by the following formula (B3), a repeating unit represented by the following formula (B4), and a repeating unit represented by the following formula (B5); In the formula, c and d are each independently an integer of 0 to 4; e1 is 0 or 1; e2 is an integer of 0 to 5; e3 is an integer of 0 to 2; R A is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; R 21 and R 22 Each of them is independently a hydroxyl group, a halogen atom, a saturated hydrocarbon group having 1 to 8 carbon atoms which may be substituted by a halogen atom, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms which may be substituted by a halogen atom, or a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms which may be substituted by a halogen atom; R 23 is a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 20 carbon atoms, a saturated hydrocarbon oxyhydrocarbyl group having 2 to 20 carbon atoms, a saturated hydrocarbon thiohydrocarbyl group having 2 to 20 carbon atoms, a halogen atom, a nitro group, a cyano group, a saturated hydrocarbon sulfinyl group having 1 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl group having 1 to 20 carbon atoms; A 3 It is a single bond or a saturated alkylene group having 1 to 10 carbon atoms, and a part of the -CH2- of the saturated alkylene group may be substituted by -O-.

7. The chemically amplified negative resist composition according to claim 5, wherein: The polymer further contains at least one selected from the group consisting of a repeating unit represented by the following formula (B6), a repeating unit represented by the following formula (B7), a repeating unit represented by the following formula (B8), a repeating unit represented by the following formula (B9), a repeating unit represented by the following formula (B10), a repeating unit represented by the following formula (B11), a repeating unit represented by the following formula (B12), and a repeating unit represented by the following formula (B13); In the formula, R B are each independently a hydrogen atom or a methyl group; Y 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 *-OY 11 -, *-C(=O)-OY 11 - or *-C(=O)-NH-Y 11 -, and Y 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 also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group; Y 2 is a single bond or **-Y 21 -C(=O)-O-, and Y 21 It is a hydrocarbon group having 1 to 20 carbon atoms which may also contain heteroatoms; Y 3 is a single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, *-OY 31 -, *-C(=O)-OY 31 - or *-C(=O)-NH-Y 31 -;Y 31 An aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, a phenylene group substituted with a trifluoromethyl group, or a group having 7 to 20 carbon atoms obtained by combining these groups, and may contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group; * is the atomic bond to the carbon atom of the main chain, ** is the atomic bond to the oxygen atom in the formula; Y 4 is a single bond or an alkylene group having 1 to 30 carbon atoms which may contain a hetero atom; f1 and f2 are independently 0 or 1, but in Y 4 When it is a single bond, f1 and f2 are 0; R 31 ~R 48 are independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom; and R 31 and R 32 They may also be bonded to each other and to the sulfur atom to which they are bonded to form a ring, and R 33 and R 34 , R 36 and R 37 , or R 39 and R 40 They can also bond to each other and to the sulfur atoms to which they are bonded to form a ring; R HF is a hydrogen atom or a trifluoromethyl group; XA - It is a non-nucleophilic relative ion.

8. The chemically amplified negative resist composition according to claim 7, wherein: The polymer contains a repeating unit represented by the following formula (B1-1), a repeating unit represented by the following formula (B2-1) or a repeating unit represented by the following formula (B2-2), and a repeating unit represented by the following formula (B7); In the formula, a4, b4, R A , R B , Y 2 , R 13 , R 14 , R 33 , R 34 , R 35 and R HF Same as above.

9. The chemically amplified negative resist composition according to claim 7, wherein: The (B) base polymer further includes a polymer containing a repeating unit represented by the formula (B1) and a repeating unit represented by the formula (B2) and not containing a repeating unit represented by the formulae (B6) to (B13).

10. The chemically amplified negative resist composition according to claim 1, wherein: The content of repeating units having an aromatic ring skeleton in all repeating units of the polymer contained in the base polymer is 60 mol% or more.

11. The chemically amplified negative resist composition according to claim 1, further comprising (C) a cross-linking agent.

12. The chemically amplified negative resist composition according to claim 5, which does not contain a cross-linking agent.

13. The chemically amplified negative resist composition according to claim 1, further comprising (D) a fluorine-containing polymer, wherein the fluorine-containing polymer (D) comprises at least one selected from the group consisting of a repeating unit represented by the following formula (D1), a repeating unit represented by the following formula (D2), a repeating unit represented by the following formula (D3), and a repeating unit represented by the following formula (D4), and may or may not comprise at least one selected from the group consisting of a repeating unit represented by the following formula (D5) and a repeating unit represented by the following formula (D6); In the formula, x is an integer from 1 to 3; y is an integer satisfying 0≤y≤5+2z-x; z is 0 or 1; k is an integer from 1 to 3; R C are each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; R D are each independently a hydrogen atom or a methyl group; R 101 , R 102 , R 104 and R 105 Each is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms; R 103 , R 106 , R 107 and R 108 are independently a hydrogen atom, a hydrocarbon group having 1 to 15 carbon atoms, a fluorinated hydrocarbon group having 1 to 15 carbon atoms, or an acid-labile group, and R 103 , R 106 , R 107 and R 108 When it is a hydrocarbon group or a fluorinated hydrocarbon group, an ether bond or a carbonyl group may be inserted between the carbon-carbon bonds; R 109 A hydrogen atom or a straight-chain or branched hydrocarbon group having 1 to 5 carbon atoms, which may have a heteroatom-containing group inserted between carbon-carbon bonds; R 110 It is a linear or branched hydrocarbon group having 1 to 5 carbon atoms, which may have a heteroatom-containing group inserted between carbon-carbon bonds; R 111 A saturated hydrocarbon group having 1 to 20 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom, and a portion of -CH2- in the saturated hydrocarbon group may be replaced by an ester bond or an ether bond; Z 1 A (k+1)-valent hydrocarbon group having 1 to 20 carbon atoms or a (k+1)-valent fluorinated hydrocarbon group having 1 to 20 carbon atoms; Z 2 is a single bond, *-C(=O)-O- or *-C(=O)-NH-; * is an atomic bond to a carbon atom of the main chain; Z 3 is a single bond, -O-, *-C(=O)-OZ 31 -Z 32 - or *-C(=O)-NH-Z 31 -Z 32 -;Z 31 is a single bond or a saturated alkylene group having 1 to 10 carbon atoms; Z 32 is a single bond, an ester bond, an ether bond or a sulfonamide bond; * is an atomic bond to a carbon atom of the main chain.

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

15. The chemically amplified negative resist composition according to claim 14, wherein: The content ratio of the (A) acid generator to the (E) quencher is less than 6 in terms of mass ratio.

16. The chemically amplified negative resist composition according to claim 1, further comprising (F) an organic solvent.

17. A method for forming a resist pattern, comprising the following steps: forming a resist film on a substrate using the chemically amplified negative resist composition according to any one of claims 1 to 16, irradiating the resist film with a pattern using high-energy rays, and developing the resist film irradiated with the pattern using an alkaline developer.

18. The resist pattern forming method according to claim 17, wherein: The high-energy rays are extreme ultraviolet rays or electron beams.

19. The resist pattern forming method according to claim 17, wherein: The outermost surface of the substrate is made of a material containing at least one selected from the group consisting of chromium, silicon, tantalum, molybdenum, cobalt, nickel, tungsten and tin.

20. The resist pattern forming method according to claim 17, wherein: The substrate is a transmission type or reflection type blank mask.

21. A transmission or reflection type blank mask coated with the chemically amplified negative resist composition according to any one of claims 1 to 16.

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