Radiation-sensitive or radio-sensitive resin composition, radiation-sensitive or radio-sensitive film, pattern forming method, and method for manufacturing an electronic device

Abstract

The present invention provides a photosensitive actinic or radiation-sensitive resin composition, a photosensitive actinic or radiation-sensitive resin film formed using the above photosensitive actinic or radiation-sensitive resin composition, a pattern forming method using the above photosensitive actinic or radiation-sensitive resin composition, and a method for manufacturing an electronic device. The photosensitive actinic or radiation-sensitive resin composition includes: a resin (A) containing a repeating unit (a1) having a specific ring structure, a compound (B) that generates an acid upon irradiation with actinic rays or radiation, and a specific compound (C) whose acid capturability is reduced by decomposition upon irradiation with actinic rays or radiation.

Description

Technical Field

[0001] The present invention relates to a photosensitive actinic or radiation-sensitive resin composition, a photosensitive actinic or radiation-sensitive film, a pattern forming method, and a method for manufacturing an electronic device. Background Art

[0002] In the manufacturing process of semiconductor devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrated Circuits), fine processing is performed by lithography using a photosensitive composition.

[0003] As a lithography method, a method can be cited in which an antireflective film is formed from a photosensitive composition, the obtained film is then exposed, and then developed. In particular, in recent years, research has been conducted on using EB (Electron Beam) and EUV (Extreme ultraviolet) light in addition to ArF excimer laser during exposure, and a photosensitive actinic or radiation-sensitive resin composition suitable for EUV exposure has been developed.

[0004] In forming an antireflective pattern using EUV (wavelength 13.5 nm) for the purpose of forming a fine pattern, compared with the case of using conventional ArF (wavelength 193 nm) light or the like, it is necessary to appropriately suppress the diffusion of acid. As an acid diffusion control agent, a compound whose alkalinity is reduced by irradiation with actinic rays or radiation is often used.

[0005] For example, Patent Document 1 discloses a photosensitive actinic or radiation-sensitive resin composition containing a resin having a monocyclic structure containing a sulfonyl group, a photoacid generator, and a basic compound. As the basic compound, a basic compound or an ammonium salt compound whose alkalinity is reduced by irradiation with actinic rays or radiation is described.

[0006] Patent Document 2 discloses a chemically amplified antireflective material containing a resin having a sulfonyl group, a photoacid generator, and a component having relative alkalinity to acid and a compound whose alkalinity is reduced by irradiation with radiation.

[0007] Patent Document 3 discloses a chemically amplified antireflective material containing a resin having a polycyclic structure containing a sulfonyl group, a photoacid generator, and a compound that is sensitive to high-energy rays or heat and generates a sulfonic acid having a specific nitrogen-containing group.

[0008] Patent Document 4 discloses a composition containing a resin having a monocyclic structure containing a sulfonyl group, a photoacid generator, and an acid diffusion control agent, and describes that as the acid diffusion control agent, a photodecomposable base that generates a weak acid by exposure to light can be used.

[0009] Prior Art Documents

[0010] Patent Documents

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-178645

[0012] Patent Document 2: Japanese Patent Application Laid-Open No. 2019-168475

[0013] Patent Document 3: Japanese Patent Application Laid-Open No. 2013-209360

[0014] Patent Document 4: International Publication No. 2018 / 074382 Pamphlet Summary of the Invention

[0015] Technical Problem to be Solved by the Invention

[0016] In recent years, there has been a demand for further reducing defects in patterns formed using EUV light. Moreover, good LWR (line width roughness) performance of the obtained patterns is required.

[0017] In the course of research by the present inventors, it was newly found that the LWR performance of the compositions described in Patent Documents 1 to 4 when forming patterns after long-term storage (for example, 180 days) after production and the defect suppression performance of the patterns formed when a standing time is provided after coating the compositions are insufficient.

[0018] Therefore, an object of the present invention is to provide a photosensitive or radiation-sensitive resin composition that has excellent LWR performance even in the case of long-term storage in patterns formed using EUV light and can suppress the generation of pattern defects even in the case of providing a standing time after coating.

[0019] Moreover, an object of the present invention is to provide a photosensitive or radiation-sensitive film, a pattern forming method, and a method for manufacturing an electronic device using the above-mentioned photosensitive or radiation-sensitive resin composition.

[0020] Means for Solving the Technical Problem

[0021] The present inventors have found that the above-mentioned problems can be solved by the following configuration. [1]

[0023] A photosensitive or radiation-sensitive resin composition containing:

[0024] (A) A resin containing a repeating unit (a1) having a structure represented by the following general formula (1);

[0025] (B) A compound that generates an acid upon irradiation with actinic rays or radiation; and

[0026] (C) An ionic compound that is decomposed upon irradiation with actinic rays or radiation to reduce acid capturability, has an anionic acid-capturing group, does not have a nonionic acid-capturing group, and contains a fluorine atom in the anion part.

[0027] [Chemical formula 1]

[0028]

[0029] In the general formula (1),

[0030] n a1 represents an integer of 1 or more.

[0031] R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom, or a hydroxyl group. When n a1 represents an integer of 2 or more, a plurality of R 1 and R 2 can be the same or different from each other.

[0032] * represents the bonding position. [2]

[0034] The photosensitive actinic ray- or radiation-sensitive resin composition according to [1], wherein

[0035] the repeating unit (a1) is a repeating unit (a1-2) represented by the following general formula (1-2).

[0036] [Chemical formula 2]

[0037]

[0038] In the general formula (1-2),

[0039] X a1 represents a hydrogen atom, an alkyl group, or a halogen atom.

[0040] A a1 represents a single bond, a divalent chain hydrocarbon group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0041] n a1 represents an integer of 1 or more.

[0042] R1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom or a hydroxyl group. When n a1 represents an integer of 2 or more, a plurality of R 1 and R 2 may be the same or different from each other. [3]

[0044] The photosensitive or radiation-sensitive resin composition according to [1] or [2], wherein,

[0045] the resin (A) further contains a repeating unit (a2) having an acid group. [4]

[0047] The photosensitive or radiation-sensitive resin composition according to [3], wherein,

[0048] the acid group in the repeating unit (a2) is a phenolic hydroxyl group or a fluorinated alkyl alcohol group. [5]

[0050] The photosensitive or radiation-sensitive resin composition according to any one of [1] to [4], wherein,

[0051] the ionic compound (C) is a compound represented by any one of the following general formulas (C1) to (C3).

[0052] [Chemical formula 3]

[0053] R C1 -L C1 -SO3 - M C + (C1)

[0054] In the general formula (C1),

[0055] R C1 represents a cycloalkyl group or an aryl group.

[0056] L C1 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)- or a divalent linking group formed by combining these.

[0057] Among them, at least one of R C1 and L C1 is substituted with a fluorine atom or a group having a fluorine atom.

[0058] M C + represents an organic cation.

[0059] [Chemical formula 4]

[0060] R C2 -L C2 -CO2 - M C + (C2)

[0061] In general formula (C2),

[0062] R C2 represents a cycloalkyl group or an aryl group.

[0063] L C2 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0064] Among them, R C2 and L C2 at least one of which is substituted with a fluorine atom or a group having a fluorine atom.

[0065] M C + represents an organic cation.

[0066] [Chemical formula 5]

[0067]

[0068] In general formula (C3),

[0069] A C31 and A C32 each independently represents -SO2-R PC1 or -CO-R PC2 .

[0070] R PC1 and R PC2 represent an organic group.

[0071] Among them, A C31 and A C32 at least one of which is substituted with a fluorine atom or a group having a fluorine atom.

[0072] M C + represents an organic cation. [6]

[0074] The photosensitive or radiation-sensitive resin composition according to [5], wherein

[0075] M in the above general formulas (C1) to (C3) C + is a cation represented by the following general formula (ZcI) or general formula (ZcII).

[0076] [Chemical Formula 6]

[0077]

[0078] In the general formula (ZcI),

[0079] R C01 、R C02 and R C03 each independently represent an organic group.

[0080] [Chemical Formula 7]

[0081] R C04 -I + -R C05 (ZcII)

[0082] In the general formula (ZcII),

[0083] R C04 and R C05 each independently represent an aryl group, an alkyl group or a cycloalkyl group. [7]

[0085] The photosensitive actinic ray or radiation-sensitive resin composition according to any one of [1] to [4], wherein,

[0086] The compound (B) that generates an acid by irradiation with the above actinic ray or radiation and the above ionic compound (C) are the same compound, and it is a compound that generates an acid by irradiation with actinic ray or radiation and decomposes by irradiation with actinic ray or radiation to reduce acid capturability, and it is an ionic compound (D) having an anionic acid capturability group, not having a non-ionic acid capturability group, and containing a fluorine atom in the anion part. [8]

[0088] The photosensitive actinic ray or radiation-sensitive resin composition according to [7], wherein,

[0089] The above ionic compound (D) is a compound represented by the following general formula (PD).

[0090] [Chemical Formula 8]

[0091] M D1 + A D1 - -L D -B D1 - M D2 + (PD)

[0092] In the general formula (PD),

[0093] MD1 + and M D2 + each independently represents an organic cation.

[0094] L D represents a divalent organic group.

[0095] A D1 - and B D1 - each independently represents an acid anion group.

[0096] L D 、A D1 - and B D1 - at least any one of them is substituted with a fluorine atom or a group having a fluorine atom.

[0097] Among them, in the compound represented by the general formula (PD), M D1 + and M D2 + are each substituted with a hydrogen atom to form HA D1 -L D -B D1 H. In the compound represented by HA D1 the pKa of the group represented by HA is lower than the pKa of the group represented by B D1 H. [9]

[0099] The photosensitive actinic ray or radiation-sensitive resin composition according to [7] or [8], wherein,

[0100] in addition to the above ionic compound (D), it further contains at least one of the above compound (B) that generates an acid upon irradiation with actinic rays or radiation and the above ionic compound (C).

[10]

[0102] The photosensitive actinic ray or radiation-sensitive resin composition according to any one of [1] to [9], wherein,

[0103] the above ionic compound (C) has a fluorine atom in the cationic part.

[11]

[0105] The photosensitive actinic ray or radiation-sensitive resin composition according to any one of [1] to

[10] , wherein,

[0106] the above compound (B) that generates an acid upon irradiation with actinic rays or radiation has a fluorine atom in the cationic part.

[12]

[0108] A photosensitive radiation or radiation-sensitive film formed using the photosensitive radiation or radiation-sensitive resin composition according to any one of [1] to

[11] .

[13]

[0110] A pattern forming method having:

[0111] A step of forming a resist film on a substrate using the photosensitive radiation or radiation-sensitive resin composition according to any one of [1] to

[11] ;

[0112] A step of exposing the above resist film; and

[0113] A step of developing the resist film exposed above with a developer to form a pattern.

[14]

[0115] A method for manufacturing an electronic device, which includes the pattern forming method described in

[13] .

[0116] Advantages of the Invention

[0117] According to the present invention, it is possible to provide a photosensitive radiation or radiation-sensitive resin composition that can obtain a pattern with excellent LWR performance even after long-term storage in a pattern formed using EUV light, and can suppress the generation of pattern defects even when there is a retention time after coating.

[0118] Furthermore, according to the present invention, it is possible to provide a photosensitive radiation or radiation-sensitive film, a pattern forming method, and a method for manufacturing an electronic device using the above photosensitive radiation or radiation-sensitive resin composition. Detailed Embodiments

[0119] Hereinafter, an example of a mode for carrying out the present invention will be described.

[0120] In addition, in this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as the lower limit value and the upper limit value.

[0121] Unless otherwise specified, the bonding direction of the divalent group marked in this specification is not limited. For example, when Y in a compound represented by the general formula "X-Y-Z" is -COO-, Y can be -CO-O- or -O-CO-. And the above compound can be "X-CO-O-Z" or "X-O-CO-Z".

[0122] In this specification, “(meth)acrylic acid” is a general term encompassing acrylic acid and methacrylic acid, and refers to “at least one of acrylic acid and methacrylic acid”. Similarly, “(meth)acrylate” refers to “at least one of acrylate and methacrylate”.

[0123] In this specification, “actinic rays” or “radiation” refers to, for example, the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, extreme ultraviolet rays (EUV light: Extreme Ultraviolet), X-rays, and electron beams (EB: Electron Beam). “Light” in this specification refers to actinic rays or radiation.

[0124] Unless otherwise specified, “exposure” in this specification includes not only exposure using the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, extreme ultraviolet rays, X-rays, and EUV light, but also drawing using particle rays such as electron beams and ion beams.

[0125] In this specification, the weight average molecular weight (Mw), number average molecular weight (Mn), and dispersity (also referred to as molecular weight distribution) (Mw / Mn) of a resin are defined as polystyrene conversion values determined by GPC (Gel Permeation Chromatography) measurement using a GPC apparatus (HLC-8120GPC manufactured by TOSOH CORPORATION) (solvent: tetrahydrofuran, flow rate (sample injection volume): 10 μL, column: TSK gel Multipore HXL-M manufactured by TOSOH CORPORATION, column temperature: 40 °C, flow rate: 1.0 mL / minute, detector: refractive index detector).

[0126] is 1 × 10 -10 m.

[0127] In this specification, the acid dissociation constant (pKa) represents the pKa in an aqueous solution. Specifically, it is calculated using the following Package 1 to obtain the value based on the Hammett substituent constant and the database of known literature values. All the pKa values described in this specification represent the values calculated using this package.

[0128] Package 1: Advanced Chemistry Development (ACD / Labs) Software V8.14 for Solaris (1994 - 2007 ACD / Labs).

[0129] On the other hand, the pKa can also be obtained by molecular orbital algorithms. As a specific method thereof, a method of calculating by calculating the dissociation free energy of H in a solvent based on a thermodynamic cycle can be cited. (In addition, in the present specification, water is usually used as the above-mentioned solvent, and DMSO (dimethyl sulfoxide) is used when the pKa cannot be obtained with water.) + (In addition, in the present specification, water is usually used as the above-mentioned solvent, and DMSO (dimethyl sulfoxide) is used when the pKa cannot be obtained with water.)

[0130] Regarding the calculation method of the dissociation free energy of H + For example, it can be calculated by DFT (density functional method), but various other methods have been reported in the literature and the like, and it is not limited thereto. In addition, there are multiple software that can implement DFT, for example, Gaussian16 can be cited.

[0131] As described above, the pKa in the present specification refers to the value obtained by calculating the value of the Hammett-based substituent constant and the known literature value database using the software package 1. However, when the pKa cannot be calculated by this method, the value obtained by Gaussian16 based on DFT (density functional method) is adopted.

[0132] In the labeling of groups (atomic groups) in the present specification, the unsubstituted and unsubstituted labels include not only groups without substituents but also groups with substituents. For example, "alkyl" includes not only alkyl groups without substituents (unsubstituted alkyl groups) but also alkyl groups with substituents (substituted alkyl groups). And the "organic group" in the present specification refers to a group containing at least one carbon atom.

[0133] In addition, in the present specification, the type, position, and number of substituents when "may have substituents" are not particularly limited. The number of substituents can be, for example, 1, 2, 3, or more. As an example of the substituent, a monovalent non-metal atomic group other than a hydrogen atom can be cited, and it can be selected from the following substituents T, for example.

[0134] (Substituent T)

[0135] As the substituent T, examples thereof include halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom; alkoxy groups such as methoxy group, ethoxy group and tert-butoxy group; aryloxy groups such as phenoxy group and p-tolyloxy group; alkoxycarbonyl groups such as methoxycarbonyl group, butoxycarbonyl group and phenoxycarbonyl group; acyloxy groups such as acetoxy group, propionyloxy group and benzoyloxy group; acyl groups such as acetyl group, benzoyl group, isobutyryl group, acryloyl group, methacryloyl group and methoxyacetyl group; alkylthio groups such as methylthio group and tert-butylthio group; arylthio groups such as phenylthio group and p-tolylthio group; alkyl group; cycloalkyl group; aryl group; heteroaryl group; hydroxyl group; carboxyl group; formyl group; sulfo group; cyano group; alkylaminocarbonyl group; arylaminocarbonyl group; sulfonamido group; silyl group; amino group; monoalkylamino group; dialkylamino group; arylamino group; and combinations thereof.

[0136] [Photosensitive or radiation-sensitive resin composition]

[0137] The photosensitive or radiation-sensitive resin composition of the present invention (hereinafter, also referred to as "resist composition") will be described.

[0138] The resist composition of the present invention may be a positive resist composition or a negative resist composition. Further, it may be a resist composition for alkaline development or a resist composition for organic solvent development. The composition of the present invention is typically a chemically amplified resist composition.

[0139] The resist composition of the present invention contains: resin (A) containing a repeating unit (a1) having a structure represented by the following general formula (1); compound (B) which generates an acid upon irradiation with actinic rays or radiation; and ionic compound (C) which is a compound whose acid capturability is reduced by decomposition upon irradiation with actinic rays or radiation, has an anionic acid capturability group, does not have a nonionic acid capturability group, and contains a fluorine atom in the anion part.

[0140] Further, in the resist composition of the present invention, the compound (B) which generates an acid upon irradiation with actinic rays or radiation and the ionic compound (C) may be the same compound.

[0141] Although the mechanism of solving the problems of the present invention by this structure is not necessarily clear, the present inventors consider as follows.

[0142] When forming a resist pattern using EUV (wavelength 13.5 nm) for the purpose of forming a fine pattern, compounds that have been used as acid diffusion control agents and whose alkalinity decreases upon irradiation with actinic rays or radiation have strong interactions between the acid diffusion control agents because they have hydrophilic onium salt structures, acid-trapping groups such as amino groups, etc. Therefore, if a long storage period is set after preparing the resist composition or a standing time is set after coating the resist composition, the acid diffusion control agents in the resist composition aggregate with each other, resulting in deterioration of the LWR performance or an increase in defects in the obtained pattern.

[0143] In the present invention, in order to mitigate the above-mentioned influence, as the acid diffusion control agent, among compounds whose alkalinity decreases upon irradiation with actinic rays or radiation, an ionic compound that does not have an acid-trapping group that enhances aggregability like an amino group, has an ionic acid-trapping group, and contains a fluorine atom in the anionic part is used. Thereby, the interaction between the acid diffusion control agents can be weakened.

[0144] Furthermore, in the present invention, a resin having a monocyclic ring structure containing a sulfonyl group (-SO2-) as a ring member is used. By using a resin having a monocyclic ring structure containing a sulfonyl group as a ring member, which has appropriate interactivity with the acid diffusion control agent, the dispersibility of the acid diffusion control agent can be improved. When a sulfonyl group is included in a chain-like group, since the degree of freedom of the chain-like group containing the sulfonyl group is high, the interaction with the acid diffusion control agent is too strong, resulting in uneven distribution of the acid diffusion control agent around the sulfonyl group. And when a sulfonyl group is included in a polycyclic ring structure, since the degree of freedom of the cyclic structure containing the sulfonyl group is low, the interaction with the acid diffusion control agent is too weak, which is not conducive to the dispersion of the acid diffusion control agent.

[0145] Thus, it can be speculated that by suppressing the aggregation of the acid diffusion control agent, a pattern with excellent LWR performance can be obtained even when the resist composition is stored for a long time, and the generation of pattern defects can be suppressed even when a standing time occurs.

[0146] 〔Components of the resist composition〕

[0147] Hereinafter, the components that the resist composition may contain will be described in detail.

[0148] <(A) Resin>

[0149] The resist composition contains a resin (A).

[0150] The resin (A) is typically an acid-decomposable resin, and is a resin whose polarity increases by the action of an acid, thereby increasing the solubility in an alkaline developer and decreasing the solubility in an organic solvent.

[0151] The resin (A) has a group that decomposes by the action of an acid to generate a polar group (in other words, a structure in which a polar group is protected by a leaving group that detaches by the action of an acid). This group (structure) is also referred to as an acid-decomposable group. The resin having an acid-decomposable group (i.e., a resin containing a repeating unit having an acid-decomposable group) increases in polarity by the action of an acid, thereby increasing its solubility in an alkaline developer and decreasing its solubility in an organic solvent.

[0152] (Repeating unit (a1))

[0153] The resin (A) contains a repeating unit (a1) having a structure represented by the following general formula (1).

[0154] [Chemical formula 9]

[0155]

[0156] In general formula (1),

[0157] n a1 represents an integer of 1 or more.

[0158] R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom, or a hydroxyl group. When n a1 represents an integer of 2 or more, a plurality of R 1 and R 2 may be the same or different from each other.

[0159] * represents the bonding position.

[0160] In general formula (1), n a1 represents an integer of 1 or more.

[0161] n a1 is preferably an integer of 1 to 5, more preferably an integer of 3 to 5.

[0162] In general formula (1), R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom, or a hydroxyl group.

[0163] R 1 ~R 4 Examples of the alkyl group when R

[0164] ~R

[0165] ~R 1 ~R4 When representing a halogen atom, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, and a fluorine atom is preferred.

[0166] R 1 ~R 4 are each independently preferably a hydrogen atom, a fluorine-substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, or a hydroxyl group, more preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxyl group, and still more preferably a hydrogen atom.

[0167] The repeating unit (a1) is preferably a repeating unit (a1-2) represented by the following general formula (1-2).

[0168] ·Repeating unit (a1-2)

[0169] [Chemical formula 10]

[0170]

[0171] In the general formula (1-2),

[0172] X a1 represents a hydrogen atom, an alkyl group, or a halogen atom.

[0173] A a1 represents a single bond, a divalent chain hydrocarbon group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0174] n a1 represents an integer of 1 or more.

[0175] R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom, or a hydroxyl group. When n a1 represents an integer of 2 or more, multiple Rs 1 and Rs 2 can be the same or different from each other.

[0176] In the general formula (1-2),

[0177] X a1 represents a hydrogen atom, an alkyl group, or a halogen atom.

[0178] X a1 When X represents an alkyl group, examples of the alkyl group include a linear or branched alkyl group having 1 to 12 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0179] Examples of the substituent when the above alkyl group has a substituent include the substituents described in the above substituent T, preferably a halogen atom, and more preferably a fluorine atom.

[0180] As X a1When representing a halogen atom, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, and a fluorine atom is preferred.

[0181] X a1 It is preferably a hydrogen atom, a fluorine-substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, or a fluorine atom, more preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a fluorine atom, and still more preferably a hydrogen atom, a methyl group, or a fluorine atom.

[0182] In the general formula (1-2), A a1 represents a single bond, a divalent chain hydrocarbon group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0183] As A a1 When the hydrocarbon group represents a divalent chain hydrocarbon group, examples of the hydrocarbon group include a chain alkylene group having 1 to 18 carbon atoms, a chain alkenylene group having 2 to 18 carbon atoms, and a chain alkynylene group having 2 to 18 carbon atoms.

[0184] Examples of the chain alkylene group having 1 to 18 carbon atoms include a methylene group, a vinyl group, a n-propylene group, a n-butylene group, a n-pentylene group, etc., and a methylene group, a vinyl group, or a n-propylene group is preferred, a methylene group or a vinyl group is more preferred, and a methylene group is still more preferred.

[0185] Examples of the chain alkenylene group having 2 to 18 carbon atoms include a vinyl group, a n-propenylene group, a 1-butenyl group, a 2-butenyl group, etc.

[0186] Examples of the chain alkynylene group having 2 to 18 carbon atoms include an ethynylene group, a n-propynylene group, a 1-butynylene group, a 2-butynylene group, etc.

[0187] When the divalent chain hydrocarbon group has a substituent, examples of the substituent include the substituents described in the above substituent T, and a halogen atom is preferred, and a fluorine atom is more preferred.

[0188] A a1 Preferably represents a single bond, a chain alkylene group having 1 to 18 carbon atoms, -O-, -C(=O)-, or a divalent linking group formed by combining these, more preferably represents a single bond, a methylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these, still more preferably a single bond or a methylene group, and particularly preferably a single bond.

[0189] In the general formula (1-2), n a1 and R 1 ~R 4 have the same meanings as n a1 and R 1 ~R 4 in the above general formula (1), and the preferred examples are also the same.

[0190] Hereinafter, the repeating units corresponding to the repeating unit (a1) are exemplified, but the present invention is not limited to these.

[0191] [Chemical Formula 11]

[0192]

[0193] In the resin (A), one kind of the repeating unit (a1) can be used alone, or two or more kinds can be used.

[0194] In the resin (A), the content of the above-mentioned repeating unit (a1) is preferably 5 to 70% by mass, more preferably 5 to 50% by mass, and still more preferably 5 to 30% by mass with respect to all the repeating units of the resin (A).

[0195] (Repeating unit (a2))

[0196] The resin (A) preferably further has a repeating unit (a2) containing an acid group.

[0197] As the acid group possessed by the repeating unit (a2), at least one group selected from the group consisting of a carboxylic acid group, a sulfonic acid group, a phenolic hydroxyl group, and a fluorinated alkyl alcohol group is preferable, and a phenolic hydroxyl group or a fluorinated alkyl alcohol group is more preferable.

[0198] · Repeating unit having a phenolic hydroxyl group

[0199] As the repeating unit having a phenolic hydroxyl group, a repeating unit represented by the following general formula (B2) is preferable.

[0200] [Chemical Formula 12]

[0201]

[0202] In the general formula (B2), X represents a hydrogen atom, an alkyl group, or a halogen atom.

[0203] The above-mentioned alkyl group may be linear or branched. The number of carbon atoms of the above-mentioned alkyl group is preferably 1 to 10.

[0204] The substituent of the above-mentioned alkyl group is preferably a hydroxyl group or a halogen atom. When the above-mentioned alkyl group has a substituent, it is preferably that the substituent has only a hydroxyl group and / or a halogen atom. The above-mentioned alkyl group is preferably -CH3.

[0205] In the general formula (B2), X4 represents a single bond, -COO-, or -CONR 64 -, R 64 represents a hydrogen atom or an alkyl group (which may be linear or branched. Preferably, the number of carbon atoms is 1 to 5). The carbonyl carbon in -COO- is preferably directly bonded to the main chain of the repeating unit.

[0206] In general formula (B2), L4 represents a single bond or an alkylene group (which may be linear or branched, preferably having 1 to 20 carbon atoms).

[0207] In general formula (B2), Ar4 represents an (n + 1)-valent aromatic ring group. The above aromatic ring group is preferably an arylene group having 6 to 18 carbon atoms such as a phenyl ring group, a naphthalene ring group, and an anthracene ring group, or an aromatic ring group containing a heterocycle such as a thiophene ring group, a furan ring group, a pyrrole ring group, a benzothiophene ring group, a benzofuran ring group, a benzopyrrole ring group, a triazine ring group, an imidazole ring group, a benzimidazole ring group, a triazole ring group, a thiadiazole ring group, and a thiazole ring group, and more preferably a phenyl ring group.

[0208] In general formula (B2), n represents an integer of 1 to 5. The (n + 1)-valent aromatic ring group may also have a substituent.

[0209] As the above R 64 The alkyl group, the alkylene group of L4, and the (n + 1)-valent aromatic ring group of Ar4 may have substituents such as a halogen atom (preferably a fluorine atom), an alkoxy group such as a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, a hydroxypropoxy group, and a butoxy group; an aryl group such as a phenyl group; etc. And, as the substituent that the (n + 1)-valent aromatic ring group of Ar4 may have, for example, an alkyl group (which may be linear or branched, preferably having 1 to 20 carbon atoms) can also be cited.

[0210] Specific examples of the repeating unit having a phenolic hydroxyl group are shown below, but the present invention is not limited thereto. In the formula, a represents 1 or 2.

[0211] [Chemical formula 13]

[0212]

[0213] [Chemical formula 14]

[0214]

[0215] [Chemical formula 15]

[0216]

[0217] In addition, among the above repeating units, the repeating units specifically described below are preferred. In the formula, R represents a hydrogen atom or a methyl group, and a represents an integer of 1 to 3.

[0218] [Chemical formula 16]

[0219]

[0220] · Repeating unit having a fluorinated alkyl alcohol group

[0221] As a repeating unit having a fluoroalkyl alcohol group, a repeating unit having a hexafluoroisopropanol group is preferred, and a repeating unit represented by the following general formula (A6) is more preferred.

[0222] [Chemical formula 17]

[0223]

[0224] In the general formula (A6),

[0225] X Q6 represents a hydrogen atom, a halogen atom or a monovalent organic group (preferably a methyl group).

[0226] R Q6 represents an alkylene group (linear or branched, preferably having 1 to 5 carbon atoms), a non-aromatic ring group or an aromatic ring group, or a group formed by combining two or more of them.

[0227] As the above non-aromatic ring group, for example, a monocyclic hydrocarbon ring group and a polycyclic hydrocarbon ring group can be cited.

[0228] As the monocyclic hydrocarbon ring group, for example, a cycloalkane ring group having 3 to 12 carbon atoms (preferably 3 to 7 carbon atoms) and a cycloalkene ring group having 3 to 12 carbon atoms can be cited.

[0229] As the polycyclic hydrocarbon ring group, for example, a ring-fused hydrocarbon ring group and a crosslinked cyclic hydrocarbon ring group can be cited.

[0230] As the crosslinked cyclic hydrocarbon ring, for example, a bicyclic hydrocarbon ring, a tricyclic hydrocarbon ring, a tetracyclic hydrocarbon ring, etc. can be cited. Further, the crosslinked cyclic hydrocarbon ring can also be a condensed ring formed by condensing a plurality of 5- to 8-membered cycloalkane rings.

[0231] The crosslinked cyclic hydrocarbon ring group is preferably a norbornane ring group, an adamantane ring group, a bicyclooctane ring group or a tricyclo[5,2,1,02,6]decane ring group.

[0232] The above aromatic ring group preferably has 6 to 18 carbon atoms, and more preferably is a benzene ring group, a naphthalene ring group, an anthracene ring group or a biphenylene ring group.

[0233] The above alkylene group, the above non-aromatic ring group and the above aromatic ring group preferably do not have substituents other than -(-C(CF3)2OH) q6 except.

[0234] In the general formula (A6), q6 represents an integer of 1 to 5.

[0235] Hereinafter, repeating units corresponding to repeating units having a fluoroalkyl alcohol group are exemplified, but the present invention is not limited to these.

[0236] [Chemical formula 18]

[0237]

[0238] [Chemical formula 19]

[0239]

[0240] Specific examples of the monomer corresponding to the repeating unit (a2) having an acid group other than a phenolic hydroxyl group and a fluorinated alkyl alcohol group can be given, but the present invention is not limited thereto.

[0241] [Chemical formula 20]

[0242]

[0243] When the resin (A) has the repeating unit (a2), its content is preferably 1 to 60% by mass, more preferably 5 to 50% by mass, and still more preferably 5 to 40% by mass, based on all the repeating units of the resin (A).

[0244] The repeating unit (a2) may be used alone or in combination of two or more.

[0245] (Repeating unit (a3) having an acid-decomposable group)

[0246] The resin (A) may further contain a repeating unit having an acid-decomposable group (also referred to as "repeating unit (a3)").

[0247] The acid-decomposable group preferably has a structure in which a polar group is protected by a group (leaving group) that is cleaved by the action of an acid.

[0248] Examples of the polar group include acidic groups such as a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group, a sulfonic acid group, a sulfonamide group, a sulfimide group, (alkylsulfonyl)(alkylcarbonyl)methylene, (alkylsulfonyl)(alkylcarbonyl)imide, bis(alkylcarbonyl)methylene, bis(alkylcarbonyl)imide, bis(alkylsulfonyl)methylene, bis(alkylsulfonyl)imide, tris(alkylcarbonyl)methylene, and tris(alkylsulfonyl)methylene (typically, a group that dissociates in a 2.38% by mass aqueous solution of tetramethylammonium hydroxide) and an alcohol hydroxyl group.

[0249] In addition, the alcohol hydroxyl group is a hydroxyl group bonded to a hydrocarbon group, and refers to a hydroxyl group other than a hydroxyl group directly bonded to an aromatic ring (phenolic hydroxyl group), excluding an aliphatic alcohol in which the α-position of the hydroxyl group is substituted with an electron-withdrawing group such as a fluorine atom (e.g., hexafluoroisopropanol group). As the alcohol hydroxyl group, a hydroxyl group having a pKa (acid dissociation constant) of 12 or more and 20 or less is preferred.

[0250] Among them, as the polar group, a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), or a sulfonic acid group is preferred.

[0251] Examples of the group that is cleaved by the action of an acid (cleavable group) include the groups represented by formulae (Y1) to (Y4).

[0252] Formula (Y1): -C(Rx1)(Rx2)(Rx3)

[0253] Formula (Y2): -C(=O)OC(Rx1)(Rx2)(Rx3)

[0254] Formula (Y3): -C(R 36 )(R 37 )(OR 38 )

[0255] Formula (Y4): -C(Rn)(H)(Ar)

[0256] In formulae (Y1) and (Y2), Rx1 to Rx3 each independently represent an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), or an aryl group (monocyclic or polycyclic).

[0257] Among them, it is preferred that Rx1 to Rx3 each independently represent a linear or branched alkyl group, and more preferably Rx1 to Rx3 each independently represent a linear alkyl group.

[0258] Two of Rx1 to Rx3 may be bonded to form a monocyclic or polycyclic ring.

[0259] The alkyl group as Rx1 to Rx3 is not particularly limited, and examples thereof include alkyl groups having 1 to 20 carbon atoms, preferably alkyl groups having 1 to 4 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tert-butyl.

[0260] The cycloalkyl group as Rx1 to Rx3 is not particularly limited, and examples thereof include cycloalkyl groups having 3 to 20 carbon atoms, preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl, and polycyclic cycloalkyl groups such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl.

[0261] The aryl group of Rx1 to Rx3 is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include phenyl, naphthyl, and anthryl.

[0262] The alkyl group, cycloalkyl group, and aryl group may have substituents.

[0263] The cycloalkyl group formed by bonding two of Rx1 to Rx3 is preferably a monocyclic cycloalkyl group such as cyclopentyl and cyclohexyl, and a polycyclic cycloalkyl group such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl, and more preferably a monocyclic cycloalkyl group having 5 to 6 carbon atoms.

[0264] In the cycloalkyl group formed by bonding two of Rx1 to Rx3, for example, one of the methylene groups constituting the ring may be substituted with a heteroatom group having a heteroatom such as an oxygen atom or a heteroatom group having a heteroatom such as a carbonyl group.

[0265] The cycloalkyl group formed by bonding two of Rx1 to Rx3 may have a substituent.

[0266] In formula (Y3), R 36 ~R 38 each independently represents a hydrogen atom or a monovalent organic group. R 37 and R 38 may bond to each other to form a ring. Examples of the monovalent organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group. R 36 is also preferably a hydrogen atom.

[0267] As formula (Y3), a group represented by the following formula (Y3-1) is preferred.

[0268] [Chemical formula 21]

[0269]

[0270] Herein, L1 and L2 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a group formed by combining them (for example, a group formed by combining an alkyl group and an aryl group).

[0271] M represents a single bond or a divalent linking group.

[0272] Q represents an alkyl group that may contain a heteroatom, a cycloalkyl group that may contain a heteroatom, an aryl group that may contain a heteroatom, an amino group, an ammonium group, a mercapto group, a cyano group, an aldehyde group, or a group formed by combining them (for example, a group formed by combining an alkyl group and a cycloalkyl group).

[0273] In the alkyl group and the cycloalkyl group, for example, one of the methylene groups may be substituted with a heteroatom group having a heteroatom such as an oxygen atom or a heteroatom group having a heteroatom such as a carbonyl group.

[0274] In addition, it is preferred that one of L1 and L2 is a hydrogen atom and the other is an alkyl group, a cycloalkyl group, an aryl group, or a group formed by combining an alkylene group and an aryl group.

[0275] At least two of Q, M, and L1 may bond to each other to form a ring (preferably a 5-membered ring or a 6-membered ring).

[0276] From the viewpoint of miniaturization of the pattern, L2 is preferably a secondary alkyl group or a tertiary alkyl group, more preferably a tertiary alkyl group. Examples of the secondary alkyl group include isopropyl group, cyclohexyl group or norbornyl group, and examples of the tertiary alkyl group include tert-butyl group or adamantyl group. In these cases, since the Tg (glass transition temperature) or activation energy increases, film strength can be ensured and blurring can be suppressed.

[0277] In formula (Y4), Ar represents an aromatic ring group. Rn represents an alkyl group, a cycloalkyl group or an aryl group. Rn and Ar may be bonded to each other to form a non-aromatic ring. Ar is more preferably an aryl group.

[0278] The resin (A) preferably has an acetal structure.

[0279] The acid-decomposable group preferably has an acetal structure. The acetal structure is, for example, a structure in which a polar group such as a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group, etc. is protected by a group represented by the above formula (Y3).

[0280] As the repeating unit having an acid-decomposable group, a repeating unit represented by formula (A) is preferred.

[0281] [Chemical formula 22]

[0282]

[0283] L1 represents a divalent linking group, R1 to R3 each independently represent a hydrogen atom or a monovalent substituent, and R4 represents a group that decomposes and detaches by the action of an acid.

[0284] L1 represents a divalent linking group. Examples of the divalent linking group include -CO-, -O-, -S-, -SO-, -SO2-, a hydrocarbon group (e.g., an alkylene group, a cycloalkylene group, an alkenylene group, an arylene group, etc.) and a linking group formed by linking a plurality of them. Among them, as L1, -CO- and an arylene group are preferred.

[0285] As the arylene group, a phenylene group is preferred.

[0286] The alkylene group may be linear or branched. The number of carbon atoms of the alkylene group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 3.

[0287] R1 to R3 each independently represent a hydrogen atom or a monovalent substituent. Examples of the monovalent substituent include an alkyl group, a cycloalkyl group or a halogen atom.

[0288] The alkyl group may be linear or branched. The number of carbon atoms of the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 3.

[0289] The cycloalkyl group can be monocyclic or polycyclic. The number of carbon atoms of the cycloalkyl group is preferably set to 3 to 8.

[0290] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0291] R4 represents a group that is eliminated by the action of an acid (eliminating group).

[0292] Among them, examples of the eliminating group include the groups represented by the above formulas (Y1) to (Y4), and the group represented by the above formula (Y3) is preferred.

[0293] When the above groups have substituents, examples of the substituents include an alkyl group (having 1 to 4 carbon atoms), a halogen atom, a hydroxyl group, an alkoxy group (having 1 to 4 carbon atoms), a carboxyl group, and an alkoxycarbonyl group (having 2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0294] As the repeating unit having an acid-decomposable group, a repeating unit represented by the general formula (AI) is also preferred.

[0295] [Chemical formula 23]

[0296]

[0297] In the general formula (AI),

[0298] Xa1 represents a hydrogen atom or an alkyl group.

[0299] T represents a single bond or a divalent linking group.

[0300] Rx1 to Rx3 each independently represent an alkyl group (linear or branched) or a cycloalkyl group (monocyclic or polycyclic). Among them, when all of Rx1 to Rx3 are alkyl groups (linear or branched), at least 2 of Rx1 to Rx3 are preferably methyl groups.

[0301] Two of Rx1 to Rx3 may also be bonded to form a cycloalkyl group (monocyclic or polycyclic).

[0302] Examples of the alkyl group represented by Xa1 include a methyl group or a group represented by -CH2-R 11 R 11 represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group. Examples thereof include an alkyl group having 5 or less carbon atoms and an acyl group having 5 or less carbon atoms. An alkyl group having 3 or less carbon atoms is preferred, and a methyl group is more preferred. As Xa1, a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group is preferred.

[0303] Examples of the divalent linking group for T include an alkylene group, an aromatic ring group, a -COO-Rt- group, and an -O-Rt- group. In the formula, Rt represents an alkylene group or a cycloalkylene group.

[0304] T is preferably a single bond or a -COO-Rt- group. When T represents a -COO-Rt- group, Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a -CH2- group, a -(CH2)2- group, or a -(CH2)3- group.

[0305] Examples of the alkyl group for Rx1 to Rx3 include alkyl groups having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, and a tert-butyl group.

[0306] Examples of the cycloalkyl group for Rx1 to Rx3 include monocyclic cycloalkyl groups such as a cyclopentyl group and a cyclohexyl group, and polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group.

[0307] Examples of the cycloalkyl group formed by bonding two of Rx1 to Rx3 include monocyclic cycloalkyl groups such as a cyclopentyl group and a cyclohexyl group. In addition, polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are also preferred. Among them, a monocyclic cycloalkyl group having 5 to 6 carbon atoms is preferred.

[0308] In the cycloalkyl group formed by bonding two of Rx1 to Rx3, for example, one of the methylene groups constituting the ring may be substituted with a group having a heteroatom such as an oxygen atom or a heteroatom-containing group such as a carbonyl group.

[0309] The repeating unit represented by the general formula (AI) is preferably a form in which, for example, Rx1 is a methyl group or an ethyl group, and Rx2 and Rx3 are bonded to form the above cycloalkyl group.

[0310] When the above groups have substituents, examples of the substituents include an alkyl group (having 1 to 4 carbon atoms), a halogen atom, a hydroxyl group, an alkoxy group (having 1 to 4 carbon atoms), a carboxyl group, and an alkoxycarbonyl group (having 2 to 6 carbon atoms). The number of carbon atoms in the substituents is preferably 8 or less.

[0311] The repeating unit represented by the general formula (AI) is preferably an acid-decomposable (meth)acrylic acid tertiary alkyl ester-based repeating unit (a repeating unit in which Xa1 represents a hydrogen atom or a methyl group and T represents a single bond).

[0312] The resin (A) may contain alone one kind of repeating unit having an acid-decomposable group, or may contain two or more kinds in combination.

[0313] The content of the repeating unit having an acid-decomposable group contained in the resin (A) (when there are a plurality of repeating units having an acid-decomposable group, it is the total thereof) is preferably 10 to 90% by mass, more preferably 20 to 80% by mass, and still more preferably 25 to 75% by mass, relative to all the repeating units of the resin (A).

[0314] (Repeating unit (a4) having a polar group)

[0315] The resin (A) may further contain a repeating unit having a polar group different from the repeating units (a1) to (a3) (also referred to as "repeating unit (a4)").

[0316] As the polar group of the repeating unit (a4), it is preferably at least one group selected from the group consisting of an ester group, a sulfonate group, a sulfonamide group, a carbonate group, a urethane group, an alcohol hydroxyl group (excluding the fluorinated alkyl alcohol group in the above repeating unit (a2)), a sulfoxide group, a sulfonyl group, a ketone group, an imide group, an amide group, a sulfonimide group, a cyano group, a nitro group, and an ether group, more preferably at least one group selected from the group consisting of a lactone group, a sultone group, a sultam group, an alcohol hydroxyl group (excluding the fluorinated alkyl alcohol group in the above repeating unit (a2)), and a cyclic carbonate group, still more preferably a lactone group or a sultone group, and particularly preferably a lactone group.

[0317] That is, the repeating unit (a4) preferably has a lactone structure or a sultone structure, and particularly preferably has a lactone structure.

[0318] As the lactone structure or the sultone structure, it suffices to have a lactone ring or a sultone ring, and preferably a lactone structure having a 5- to 7-membered lactone ring or a sultone structure having a 5- to 7-membered sultone ring.

[0319] It is also preferred that a lactone structure in which another ring is fused to a 5- to 7-membered lactone ring in the form of forming a bicyclic structure or a helical structure. It is also preferred that a sultone structure in which another ring is fused to a 5- to 7-membered sultone ring in the form of forming a bicyclic structure or a helical structure.

[0320] Among them, the resin (A) preferably contains a repeating unit having a lactone structure represented by any one of the following general formulas (LC1-1) to (LC1-22) or a sultone structure represented by any one of the following general formulas (SL1-1) to (SL1-3). And the lactone structure or the sultone structure may be directly bonded to the main chain.

[0321] Among them, it is preferably a lactone structure represented by the general formula (LC1-1), general formula (LC1-4), general formula (LC1-5), general formula (LC1-8), general formula (LC1-16), general formula (LC1-21), or general formula (LC1-22), or a sultone structure represented by the general formula (SL1-1).

[0322] [Chemical formula 24]

[0323]

[0324] The lactone structure or sultone structure may or may not have a substituent (Rb2). As the substituent (Rb2), an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, a carboxyl group, a halogen atom, a hydroxyl group, or a cyano group, etc. are preferred, and an alkyl group having 1 to 4 carbon atoms or a cyano group is more preferred. n2 represents an integer of 0 to 4. When n2 is 2 or more, multiple substituents (Rb2) may be the same or different. And multiple substituents (Rb2) may bond to each other to form a ring.

[0325] As the repeating unit having a lactone structure or a sultone structure, a repeating unit represented by the following general formula (LS1) is preferred.

[0326] [Chemical formula 25]

[0327]

[0328] In the above general formula (LS1),

[0329] A LS represents an ester bond (a group represented by -COO-) or an amide bond (a group represented by -CONH-).

[0330] t is the repetition number of the structure represented by -R LS2 -R LS3 -, represents an integer of 0 to 5, preferably 0 or 1, more preferably 0. When t is 0, (-R LS2 -R LS3 -)t becomes a single bond.

[0331] R LS2 represents an alkylene group, a cycloalkylene group, or a combination thereof. When R LS2 is present in plurality, multiple R LS2 may be the same or different respectively.

[0332] R LS2 The alkylene group or cycloalkylene group of may have a substituent.

[0333] R LS3represents a single bond, an ether bond, an ester bond, an amide bond, a urethane bond or a urea bond. When R LS3 is present in plural numbers, the plural R LS3 may be the same or different from each other.

[0334] Among them, R LS3 is preferably an ether bond or an ester bond, more preferably an ester bond.

[0335] R LS4 represents a monovalent organic group having a lactone structure or a sultone structure.

[0336] Among them, preferably, in any one of the structures represented by the aforementioned general formulas (LC1-1) to (LC1-22) and the structures represented by the general formulas (SL1-1) to (SL1-3), a group formed by removing 1 hydrogen atom from one carbon atom constituting the lactone structure or the sultone structure. In addition, the carbon atom from which the above 1 hydrogen atom is removed is preferably not a carbon atom constituting the substituent (Rb2).

[0337] R LS1 represents a hydrogen atom, a halogen atom or a monovalent organic group (preferably a methyl group).

[0338] The monomers corresponding to the repeating units having at least one selected from the group consisting of a lactone structure and a sultone structure are exemplified below.

[0339] In the following exemplification, the methyl group bonded to the vinyl group may be substituted with a hydrogen atom, a halogen atom or a monovalent organic group.

[0340] [Chemical formula 26]

[0341]

[0342] [Chemical formula 27]

[0343]

[0344] [Chemical formula 28]

[0345]

[0346] As the repeating unit (a4), a repeating unit having a carbonate group is also preferred.

[0347] The carbonate group in the repeating unit having a carbonate group is preferably included in a cyclic carbonate group.

[0348] The repeating unit having a carbonate group is preferably a repeating unit represented by the general formula (A4).

[0349] [Chemical formula 29]

[0350]

[0351] In general formula (A4),

[0352] R A 1 represents a hydrogen atom, a halogen atom or a monovalent organic group (preferably a methyl group).

[0353] n represents an integer of 0 or more (preferably 0 to 3).

[0354] R A 2 represents a substituent. When n is 2 or more, there are multiple Rs A 2 which may be the same or different from each other.

[0355] A represents a single bond or a divalent linking group. The above divalent linking group is preferably an alkylene group (preferably having 1 to 4 carbon atoms), a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, a carboxylic acid group or a divalent group formed by combining them.

[0356] Z represents an atomic group that forms a monocyclic or polycyclic ring together with the group represented by -O-CO-O- in the formula.

[0357] The monocyclic or polycyclic ring formed by Z together with the group represented by -O-CO-O- in the formula is preferably a 5-membered cyclic carbonate group, more preferably a cyclic carbonate structure represented by the following general formula (CC1-1).

[0358] That is, A in general formula (A4) is preferably bonded to a group formed by extracting one hydrogen atom from the ring member atoms of the cyclic carbonate structure represented by the following general formula (CC1-1).

[0359] [Chemical formula 30]

[0360]

[0361] The cyclic carbonate structure part in general formula (CC1-1) may have a substituent (Rb2). As preferred substituents (Rb2), for example, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, a carboxylic acid group, a halogen atom (preferably a fluorine atom), a hydroxyl group and a cyano group can be cited. n3 represents an integer of 0 or 1.

[0362] The resin (A) may contain repeating units having polar groups other than the above-mentioned lactone group, sultone group or carbonate group. As the repeating units having polar groups other than the above-mentioned lactone group, sultone group or carbonate group, repeating units having an alicyclic hydrocarbon structure substituted with the above-mentioned polar groups are preferred. As the alicyclic hydrocarbon structure in the alicyclic hydrocarbon structure substituted with a polar group, a cyclohexyl group, an adamantyl group or a norbornyl group is preferred.

[0363] Specific examples of the monomers corresponding to the repeating units having the above-mentioned polar groups are given below, but the present invention is not limited to these specific examples.

[0364] [Chemical formula 31]

[0365]

[0366] The resin (A) also preferably has, as the repeating unit (a4), the repeating units described in paragraphs

[0370] to

[0433] of the specification of US Patent Application Publication No. 2016 / 0070167A1.

[0367] When the resin (A) contains the repeating unit (a4), the type of the repeating unit (a4) contained in the resin (A) may be one type or two or more types.

[0368] When the resin (A) contains the repeating unit (a4), the content of the repeating unit (a4) contained in the resin (A) (the total content when there are a plurality of repeating units (a4)) is preferably 5 to 50% by mass, more preferably 10 to 45% by mass, and further preferably 10 to 30% by mass with respect to all the repeating units in the resin (A).

[0369] (Other repeating units)

[0370] In addition, the resin (A) may further contain a repeating unit (a5) represented by the following formula (D).

[0371] [Chemical formula 32]

[0372]

[0373] In formula (D), "cylic" represents a group in which a main chain is formed by a cyclic structure. The number of atoms constituting the ring is not particularly limited.

[0374] As the repeating unit represented by formula (D), for example, the following repeating units can be cited.

[0375] [Chemical formula 33]

[0376]

[0377] In the above formulae, each R independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR” or -COOR”: R” is an alkyl group or a fluorinated alkyl group having 1 to 20 carbon atoms) or a carboxylic acid group. Additionally, the above alkyl group, the above cycloalkyl group, the above aryl group, the above aralkyl group and the above alkenyl group may each have a substituent. Also, a hydrogen atom bonded to a carbon atom in the group represented by R may be substituted with a fluorine atom or an iodine atom. In the above formulae, each R’ independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR” or -COOR”: R” is an alkyl group or a fluorinated alkyl group having 1 to 20 carbon atoms) or a carboxylic acid group. Additionally, the above alkyl group, the above cycloalkyl group, the above aryl group, the above aralkyl group and the above alkenyl group may each have a substituent. Also, a hydrogen atom bonded to a carbon atom in the group represented by R’ may be substituted with a fluorine atom or an iodine atom.

[0378] m represents an integer of 0 or more. There is no particular limitation on the upper limit of m, but it is usually 2 or less, and more often 1 or less.

[0379] When the resin (A) contains a repeating unit represented by the formula (D) (repeating unit (a5)), its content is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, and still more preferably 5 to 30% by mass relative to all the repeating units of the resin (A).

[0380] In addition, the resin (A) may further contain a repeating unit (a6) represented by the following formula (E).

[0381] [Chemical formula 34]

[0382]

[0383] In the formula (E), each Re independently represents a hydrogen atom or an organic group. Examples of the organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group and an alkenyl group, etc., which may have a substituent.

[0384] “cylic” is a cyclic group containing a carbon atom in the main chain. There is no particular limitation on the number of atoms contained in the cyclic group.

[0385] Examples of the repeating unit represented by the formula (E) include the following repeating units.

[0386] [Chemical formula 35]

[0387]

[0388] In the above formulae, each R independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR" or -COOR": R" is an alkyl group or a fluorinated alkyl group having 1 to 20 carbon atoms) or a carboxylic acid group. Further, the above alkyl group, the above cycloalkyl group, the above aryl group, the above aralkyl group and the above alkenyl group may each have a substituent. Also, a hydrogen atom bonded to a carbon atom in the group represented by R may be substituted with a fluorine atom or an iodine atom.

[0389] Each R' independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR" or -COOR": R" is an alkyl group or a fluorinated alkyl group having 1 to 20 carbon atoms) or a carboxylic acid group. Further, the above alkyl group, the above cycloalkyl group, the above aryl group, the above aralkyl group and the above alkenyl group may each have a substituent. Also, a hydrogen atom bonded to a carbon atom in the group represented by R' may be substituted with a fluorine atom or an iodine atom.

[0390] m represents an integer of 0 or more. The upper limit of m is not particularly limited, but is usually 2 or less, and more often 1 or less.

[0391] Also, in formula (E-2), formula (E-4), formula (E-6), formula (E-8) and formula (E-12), two Rs may be bonded to each other to form a ring.

[0392] When the resin (A) contains the repeating unit (a6)) represented by formula (E), its content is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, and still more preferably 5 to 30% by mass relative to all the repeating units of the resin (A).

[0393] Within the range not hindering the effects of the present invention, the resin (A) may contain, as other repeating units, repeating units other than the above, for example, may have a repeating unit containing a photoacid generator group.

[0394] The repeating unit having a photoacid generator group is not particularly limited, and is preferably a repeating unit represented by the general formula (A7) (repeating unit (a7)).

[0395] [Chemical formula 36]

[0396]

[0397] In the general formula (A7), two Xf each independently represent a hydrogen atom, a fluorine atom or an alkyl group substituted with at least one fluorine atom (preferably CF3). Among the two Xf, at least one is preferably an atom other than a hydrogen atom.

[0398] The above-mentioned alkyl group may be linear or branched. The number of carbon atoms of the above-mentioned alkyl group is preferably 1 to 10. The above-mentioned alkyl group preferably has only fluorine atoms as substituents.

[0399] In general formula (A7), R 1 and R 2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group, and when there are a plurality of R's 1 and R 2 may be the same or different from each other.

[0400] The above-mentioned alkyl group may be linear or branched. The number of carbon atoms of the above-mentioned alkyl group is preferably 1 to 10. The substituent of the above-mentioned alkyl group is preferably a fluorine atom. When the above-mentioned alkyl group has a substituent, it preferably has only fluorine atoms as substituents.

[0401] In general formula (A7), L represents a divalent linking group, and when there are a plurality of L's, they may be the same or different.

[0402] Examples of the divalent linking group of L include -COO-, -CO-, -O-, -S-, -SO-, -SO2-, alkylene, cycloalkylene, alkenylene, and a linking group formed by linking a plurality of these, and a linking group having 12 or less carbon atoms in total is preferred.

[0403] In general formula (A7), x represents an integer of 1 to 20, y represents an integer of 0 to 10, and z represents an integer of 0 to 10.

[0404] In general formula (A7), X 7 represents a hydrogen atom, an alkyl group or a halogen atom.

[0405] As the alkyl group when X 7 represents an alkyl group, linear or branched alkyl groups having 1 to 12 carbon atoms can be mentioned, preferably methyl, ethyl, isopropyl or n-propyl, more preferably methyl or ethyl, and still more preferably methyl.

[0406] As the substituent when the above-mentioned alkyl group has a substituent, the substituents described in the above-mentioned substituent T can be mentioned.

[0407] As X 7 when representing a halogen atom, fluorine atom, chlorine atom, bromine atom or iodine atom can be mentioned, and a fluorine atom is preferred.

[0408] In general formula (A7), M + represents a cation. Regarding the details of M + , for example, the same cation as M + in general formula (PA-1) described later can be used.

[0409] When the resin (A) has a repeating unit (a7), its content is preferably 1 to 40% by mass, more preferably 1 to 25% by mass, and further preferably 1 to 15% by mass with respect to all the repeating units of the resin (A).

[0410] The repeating unit (a7) may be used alone or in combination of two or more.

[0411] The resin (A) can be synthesized according to a conventional method (e.g., radical polymerization).

[0412] As the polystyrene conversion value based on the GPC method, the weight-average molecular weight of the resin (A) is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, and further preferably 4,500 to 15,000. If the weight-average molecular weight of the resin (A) is 1,000 to 200,000, deterioration of heat resistance and dry etching resistance can be prevented, and furthermore, deterioration of developability and increase in viscosity resulting in deterioration of film-forming properties can be prevented.

[0413] The dispersity (molecular weight distribution) of the resin (A) is usually 1 to 5, preferably 1 to 3, more preferably 1.2 to 3.0, and further preferably 1.2 to 2.0. The smaller the dispersity, the more excellent the resolution and resist shape, and the smoother the sidewall of the resist pattern and the more excellent the roughness.

[0414] In the resist composition, the content of the resin (A) is preferably 50 to 99.9% by mass, more preferably 60 to 99.0% by mass in the total solid content. And the resin (A) may be used alone or in combination of two or more.

[0415] <(B) Compound that generates an acid upon irradiation with actinic rays or radiation>

[0416] The resist composition may contain a compound that generates an acid upon irradiation with actinic rays or radiation (also referred to as a photoacid generator or photoacid generator (B)). The photoacid generator is a compound that generates an acid upon exposure (preferably exposure to EUV light).

[0417] The photoacid generator may be in the form of a low-molecular compound or in the form of being incorporated into a part of a polymer. And the form of a low-molecular compound and the form of being incorporated into a part of a polymer may be used in combination.

[0418] When the photoacid generator is in the form of a low-molecular compound, the molecular weight is preferably 3000 or less, more preferably 2000 or less, and further preferably 1000 or less.

[0419] When the photoacid generator is in the form of being incorporated into a part of a polymer, it may be incorporated into a part of the resin (A) or into a resin different from the resin (A).

[0420] In the present invention, the photoacid generator is preferably in the form of a low molecular compound.

[0421] The photoacid generator is not particularly limited, and among them, a compound that generates an organic acid by irradiation with EUV light is preferred, and a photoacid generator having a fluorine atom or an iodine atom in the molecule is more preferred.

[0422] Examples of the above organic acids include sulfonic acids (aliphatic sulfonic acids, aromatic sulfonic acids, camphorsulfonic acids, etc.), carboxylic acids (aliphatic carboxylic acids, aromatic carboxylic acids, aralkyl carboxylic acids, etc.), carbonylsulfonimide acids, bis(alkylsulfonyl)imide acids, and tris(alkylsulfonyl)methylated acids.

[0423] In the present invention, the strength of the acid generated by the photoacid generator (B) is not particularly limited. For example, the pKa of the generated acid is preferably -12.00 to 1.00, more preferably -7.00 to 0.50, and further preferably -5.00 to 0.00.

[0424] The volume of the acid generated by the photoacid generator is not particularly limited. From the viewpoint of suppressing the diffusion of the acid generated during exposure to the unexposed portion and improving the resolution, it is preferred above, more preferably above, further preferably above, particularly preferably above. In addition, from the viewpoints of sensitivity or solubility in the coating solvent, the volume of the acid generated by the photoacid generator is preferably below, more preferably below, further preferably below.

[0425] The above volume value is obtained using "WinMOPAC" manufactured by Fujitsu Limited. When calculating the above volume value, first input the chemical structure of the acid involved in each example, and then determine the most stable steric conformation of each acid by using the molecular force field calculation of the MM (Molecular Mechanics) 3 method with this structure as the initial structure. After that, perform molecular orbital calculations using the PM (Parameterized Model number) 3 method on these most stable steric conformations, whereby the "accessible volume" of each acid can be calculated.

[0426] The structure of the acid generated by the photoacid generator is not particularly limited. From the viewpoints of suppressing the diffusion of the acid and improving the resolution, it is preferred that the interaction between the acid generated by the photoacid generator and the resin (A) is strong. From this point of view, when the acid generated by the photoacid generator is an organic acid, it is preferred that, for example, in addition to organic acid groups such as a sulfonic acid group, a carboxylic acid group, a carbonylsulfonimide acid group, a bissulfonimide acid group, and a trisulfomethylated acid group, it also has a polar group.

[0427] Examples of the polar group include an ether group, an ester group, an amide group, an acyl group, a sulfo group, a sulfonyloxy group, a sulfonamide group, a thioether group, a thioester group, a urea group, a carbonate group, a carbamate group, a hydroxyl group, and a mercapto group.

[0428] The number of polar groups possessed by the generated acid is not particularly limited, preferably 1 or more, more preferably 2 or more. However, from the viewpoint of suppressing excessive development, it is preferred that the number of polar groups is less than 6, more preferably less than 4.

[0429] The photoacid generator is preferably a photoacid generator that generates the acids exemplified below. In addition, the calculated values of the volume are noted in some examples.

[0430] [Chemical formula 37]

[0431]

[0432] [Chemical formula 38]

[0433]

[0434] [Chemical formula 39]

[0435]

[0436] From the viewpoint of more excellent effects of the present invention, the photoacid generator is preferably a photoacid generator having an anion and a cation.

[0437] The photoacid generator preferably has a fluorine atom in the cation moiety.

[0438] (Compound represented by the general formula (PA-1))

[0439] The photoacid generator preferably contains a compound represented by the general formula (PA-1).

[0440] [Chemical formula 40]

[0441]

[0442] In the general formula (PA-1), A 1 and A 2 each independently represents -SO2-R Por -CO-R P 。R P represents an organic group.

[0443] There are two Rs in the general formula (PA-1) P which may be the same or different.

[0444] There are two Rs in the general formula (PA-1) P The number of carbon atoms of which are each independently preferably 1 to 25, more preferably 1 to 15.

[0445] Except for the two Rs in the general formula (PA-1) P the number of atoms other than the hydrogen atoms of which are each independently preferably 2 to 30, more preferably 4 to 20.

[0446] R P is preferably a group represented by the general formula (RF).

[0447] -L RF -R RF (RF)

[0448] In the general formula (RF), L RF represents a single bond or a divalent linking group.

[0449] As the above divalent linking group, for example, -COO-, -CONH-, -CO-, -O-, -S-, -SO-, -SO2-, alkylene (which may be linear or branched. Preferably having 1 to 6 carbon atoms), cycloalkylene (preferably having 3 to 15 carbon atoms), alkenylene (which may be linear or branched. Preferably having 2 to 6 carbon atoms) and a divalent linking group formed by combining multiple of them, etc. can be cited.

[0450] And, when it is possible to have a divalent linking group of them, the substituent that can be possessed is preferably a halogen atom, more preferably a fluorine atom. For example, the above alkylene (also including the alkylene that may be contained in the divalent linking group formed by combining multiple of them) is also preferably a perfluoroalkylene.

[0451] The above divalent linking group is preferably -alkylene-COO- or -alkylene-SO2-. In -alkylene-COO- and -alkylene-SO2-, alkylene is preferably present on the N-side.

[0452] In the general formula (RF), R RF represents a cycloalkyl or an alkyl.

[0453] When R RF is a cycloalkyl, the above cycloalkyl may be monocyclic or polycyclic.

[0454] The number of carbon atoms of the above cycloalkyl group is preferably 3 to 15, more preferably 5 to 10.

[0455] Examples of the above cycloalkyl group include a norbornyl group, a decahydronaphthyl group, and an adamantyl group.

[0456] The substituent that the above cycloalkyl group may have is preferably an alkyl group (which may be linear or branched. Preferably, the number of carbon atoms is 1 to 5). The above cycloalkyl group also preferably has no other substituents.

[0457] One or more of the carbon atoms of the ring member atoms of the above cycloalkyl group can be substituted by a carbonyl carbon atom and / or a heteroatom. For example, the carbon atom (-CH<) bonded to L in the cycloalkyl group can be substituted by a nitrogen atom (-N<). RF bonded carbon atom (-CH<) can be replaced by a nitrogen atom (-N<).

[0458] When R RF is an alkyl group, the above alkyl group can be linear or branched.

[0459] The number of carbon atoms of the above alkyl group is preferably 1 to 10, more preferably 1 to 5.

[0460] The substituent that the above alkyl group may have is preferably a cycloalkyl group, a fluorine atom, or a cyano group. The above alkyl group also preferably has no other substituents except these.

[0461] Examples of the cycloalkyl group as the above substituent can be the same cycloalkyl groups as those described when R RF is a cycloalkyl group.

[0462] When the above alkyl group has a fluorine atom as the above substituent, the above alkyl group may or may not be a perfluoroalkyl group. When the above alkyl group has a fluorine atom as the above substituent, it is also preferred that part or all of the above alkyl group is a perfluoromethyl group.

[0463] In the general formula (PA-1), "A 1 -N--A 2 " The two Rs contained in P can be bonded to each other to form a ring.

[0464] In the general formula (PA-1), M + represents a cation.

[0465] M + The cation of is preferably an organic cation.

[0466] The above organic cations are each independently preferably a cation represented by the general formula (ZaI) (cation (ZaI)) or a cation represented by the general formula (ZaII) (cation (ZaII)).

[0467] [Chemical formula 41]

[0468]

[0469] R 204 -I + -R 205 (ZaII)

[0470] In the above general formula (ZaI),

[0471] R 201 、R 202 and R 203 each independently represent an organic group.

[0472] As R 201 、R 202 and R 203 The organic group usually has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms. Also, two of R 201 to R 203 can be bonded to form a ring structure, and may contain an oxygen atom, a sulfur atom, an ester group, an amide group or a carbonyl group in the ring. As the group formed by bonding two of R 201 to R 203 Examples thereof include an alkylene group (e.g., butylene, pentylene, etc.) and -CH2-CH2-O-CH2-CH2-.

[0473] As the cation in the general formula (ZaI), for example, the following cation (ZaI-1), cation (ZaI-2), the cation represented by the general formula (ZaI-3b) (cation (ZaI-3b)) and the cation represented by the general formula (ZaI-4b) (cation (ZaI-4b)) can be cited.

[0474] First, the cation (ZaI-1) will be described.

[0475] The cation (ZaI-1) is an arylsulfonium cation in which at least one of R 201 to R 203 in the above general formula (ZaI) is an aryl group.

[0476] In the arylsulfonium cation, R 201 to R 203 can all be aryl groups, or a part of R 201 to R 203 can be aryl groups and the rest can be alkyl groups or cycloalkyl groups.

[0477] Also, one of R 201 to R 203 is an aryl group, and R 201 to R 203The remaining two of them can be bonded to form a ring structure, and may also contain an oxygen atom, a sulfur atom, an ester group, an amide group or a carbonyl group within the ring. As R 201 ~R 203 The group formed by bonding two of them in 201 ~ 203 , for example, an alkylene group in which one or more methylene groups can be replaced by an oxygen atom, a sulfur atom, an ester group, an amide group and / or a carbonyl group (for example, butylene, pentylene or -CH2-CH2-O-CH2-CH2-).

[0478] As the arylsulfonium cation, for example, a triarylsulfonium cation, a diarylalkylsulfonium cation, an aryldialkylsulfonium cation, a diarylcycloalkylsulfonium cation and an arylbicycloalkylsulfonium cation can be cited.

[0479] The aryl group contained in the arylsulfonium cation is preferably a phenyl group or a naphthyl group, more preferably a phenyl group. The aryl group may be an aryl group containing a heterocyclic structure such as an oxygen atom, a nitrogen atom or a sulfur atom. As the heterocyclic structure, for example, a pyrrole residue, a furan residue, a thiophene residue, an indole residue, a benzofuran residue and a benzothiophene residue can be cited. When the arylsulfonium cation has two or more aryl groups, the two or more aryl groups may be the same or different.

[0480] The alkyl group or cycloalkyl group that the arylsulfonium cation optionally has is preferably a linear alkyl group having 1 to 15 carbon atoms, a branched alkyl group having 3 to 15 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms. For example, a methyl group, an ethyl group, a propyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, a cyclopropyl group, a cyclobutyl group and a cyclohexyl group can be cited.

[0481] R 201 ~R 203 The substituents that the aryl group, alkyl group and cycloalkyl group in 201 ~ 203 may have are each independently preferably an alkyl group (for example, having 1 to 15 carbon atoms), a cycloalkyl group (for example, having 3 to 15 carbon atoms), an aryl group (for example, having 6 to 14 carbon atoms), an alkoxy group (for example, having 1 to 15 carbon atoms), a cycloalkylalkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group or a phenylthio group.

[0482] The above substituents may also have substituents when possible. For example, the above alkyl group may have a halogen atom as a substituent to become a halogenated alkyl group such as a trifluoromethyl group.

[0483] Next, the cation (ZaI-2) will be described.

[0484] The cation (ZaI-2) is a cation in which R 201 ~R 203 in the formula (ZaI) each independently represents an organic group without an aromatic ring. Here, the aromatic ring also includes an aromatic ring containing a heteroatom.

[0485] As R201 ~R 203 An organic group without an aromatic ring, usually having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

[0486] R 201 ~R 203 Are each independently preferably an alkyl group, a cycloalkyl group, an allyl group or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, a 2-oxocycloalkyl group or an alkoxycarbonylmethyl group, and further preferably a linear or branched 2-oxoalkyl group.

[0487] As R 201 ~R 203 Examples of the alkyl group and cycloalkyl group in R~R include a linear alkyl group having 1 to 10 carbon atoms or a branched alkyl group having 3 to 10 carbon atoms (e.g., methyl, ethyl, propyl, butyl, and pentyl), and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, and norbornyl).

[0488] R 201 ~R 203 May be further substituted by a halogen atom, an alkoxy group (e.g., having 1 to 5 carbon atoms), a hydroxyl group, a cyano group or a nitro group.

[0489] Next, the cation (ZaI-3b) will be described.

[0490] The cation (ZaI-3b) is a cation represented by the following general formula (ZaI-3b).

[0491] [Chemical formula 42]

[0492]

[0493] In the general formula (ZaI-3b),

[0494] R 1c ~R 5c Each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a cycloalkylcarbonyloxy group, a halogen atom, a hydroxyl group, a nitro group, an alkylthio group or an arylthio group.

[0495] R 6c and R 7c Each independently represents a hydrogen atom, an alkyl group (such as tert-butyl), a cycloalkyl group, a halogen atom, a cyano group or an aryl group.

[0496] R x and R y Each independently represents an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, an allyl group or a vinyl group.

[0497] R 1c~R 5c Any two or more of R 5c and R 6c , R 6c and R 7c , R 5c and R x and R x and R y can be bonded to each other to form a ring, and the ring can independently contain an oxygen atom, a sulfur atom, a keto group, an ester bond or an amide bond respectively.

[0498] Examples of the above ring include aromatic or non-aromatic hydrocarbon rings, aromatic or non-aromatic heterocyclic rings, and polycyclic condensed rings formed by combining two or more of these rings. The ring can be a 3- to 10-membered ring, preferably a 4- to 8-membered ring, and more preferably a 5-membered ring or a 6-membered ring.

[0499] As R 1c ~R 5c Any two or more of R 6c and R 7c and R x and R y bonded to form a group, examples of which include alkylene groups such as butylene and pentylene. The methylene group in the alkylene group can be substituted by a heteroatom such as an oxygen atom.

[0500] R 5c and R 6c and R 5c and R x bonded to form a group is preferably a single bond or an alkylene group. Examples of the alkylene group include methylene and ethylene.

[0501] Next, the cation (ZaI-4b) will be described. The cation (ZaI-4b) is a cation represented by the following general formula (ZaI-4b).

[0502] [Chemical formula 43]

[0503]

[0504] In the general formula (ZaI-4b),

[0505] l represents an integer of 0 to 2.

[0506] r represents an integer of 0 to 8.

[0507] R 13 represents a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group, an alkoxy group, an alkoxycarbonyl group or a group having a cycloalkyl group (which can be the cycloalkyl itself or a group partially containing a cycloalkyl group). These groups can also have substituents.

[0508] R14 represents a hydroxyl group, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, a cycloalkylsulfonyl group, or a group having a cycloalkyl group (which may be the cycloalkyl itself or a group partially containing a cycloalkyl group). These groups may also have substituents. When there are multiple Rs 14 they each independently represent the above-mentioned groups such as a hydroxyl group.

[0509] R 15 each independently represents an alkyl group, a cycloalkyl group, or a naphthyl group. These groups may also have substituents. Two Rs 15 may be bonded to each other to form a ring. When two Rs 15 are bonded to each other to form a ring, a heteroatom such as an oxygen atom or a nitrogen atom may be contained in the ring skeleton. In one embodiment, it is preferred that two Rs 15 are alkylene groups and are bonded to each other to form a ring structure.

[0510] In the general formula (ZaI-4b), the alkyl groups of R 13 , R 14 and R 15 are linear or branched. The number of carbon atoms of the alkyl group is preferably 1 to 10. The alkyl group is more preferably a methyl group, an ethyl group, a n-butyl group, or a tert-butyl group, etc.

[0511] Next, the general formula (ZaII) will be described. In the general formula (ZaII), R 204 and R 205 each independently represents an aryl group, an alkyl group, or a cycloalkyl group.

[0512] R 204 and R 205 The aryl group is preferably a phenyl group or a naphthyl group, more preferably a phenyl group. The aryl groups of R 204 and R 205 may be aryl groups containing a heterocycle having an oxygen atom, a nitrogen atom, or a sulfur atom, etc. As the skeleton of the aryl group having a heterocycle, for example, pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene, etc. can be cited.

[0513] R 204 and R 205 The alkyl groups and cycloalkyl groups of are preferably linear alkyl groups having 1 to 10 carbon atoms or branched alkyl groups having 3 to 10 carbon atoms (e.g., methyl, ethyl, propyl, butyl, or pentyl) or cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, or norbornyl).

[0514] R 204 and R 205 The aryl groups, alkyl groups, and cycloalkyl groups of may each independently have substituents. As R 204 and R 205Substituents that the aryl, alkyl, and cycloalkyl can have include, for example, alkyl (e.g., having 1 to 15 carbon atoms), cycloalkyl (e.g., having 3 to 15 carbon atoms), aryl (e.g., having 6 to 15 carbon atoms), alkoxy (e.g., having 1 to 15 carbon atoms), halogen atom, hydroxyl group, and phenylthio group, etc.

[0515] (Compound represented by general formula (PB))

[0516] The photoacid generator preferably further contains a compound represented by general formula (PB).

[0517] M1 + A - -L-B - M2 + (PB)

[0518] The compound represented by general formula (PB) contains, in one molecule, a structure having a function corresponding to a usual photoacid generator (corresponding to the part of “M1 + A - -”) and a structure having a function corresponding to an acid diffusion control agent (corresponding to the part of “-B - M2 + ”), and thus, in the resist film, the existence ratios of the above structures can be made constant.

[0519] Therefore, the present inventors presume that even when the resist film is exposed, the amount and diffusion of the acid generated in the resist film are likely to become uniform, and the width of the pattern obtained after development is also stable.

[0520] In general formula (PB), M1 + and M2 + each independently represent an organic cation.

[0521] M1 + and M2 + The organic cations of can each independently be the same as the organic cations exemplified in the description of M + in general formula (PA-1).

[0522] In general formula (PB), L represents a divalent organic group.

[0523] As the above divalent organic group, for example, -COO-, -CONH-, -CO-, alkylene (preferably having 1 to 6 carbon atoms. It can be linear or branched), cycloalkylene (preferably having 3 to 15 carbon atoms), alkenylene (preferably having 2 to 6 carbon atoms), and a divalent linking group formed by combining multiple of them, etc. can be cited.

[0524] One or more of the methylene groups of the cycloalkane ring constituting the above-mentioned cycloalkylene group may be substituted with a carbonyl carbon and / or a heteroatom (such as an oxygen atom).

[0525] These divalent linking groups also preferably further have a group selected from the group consisting of -O-, -S-, -SO-, and -SO2-.

[0526] Among them, L is preferably a group represented by the following general formula (L).

[0527] *A-LA-LB-LC-LD-LE-*B (L)

[0528] In the general formula (L), *A represents the bonding position with A in the general formula (PB) - . In the general formula (L), *B represents the bonding position with B in the general formula (PB) - .

[0529] In the general formula (L), LA represents -(C(R LA1 )(R LA2 )) XA -.

[0530] The above-mentioned XA represents an integer of 1 or more, preferably 1 to 10, more preferably 1 to 3.

[0531] R LA1 and R LA2 each independently represent a hydrogen atom or a substituent.

[0532] The substituents of R LA1 and R LA2 are each independently preferably a fluorine atom or a fluorinated alkyl group, more preferably a fluorine atom or a perfluoroalkyl group, and further preferably a fluorine atom or a perfluoromethyl group.

[0533] When XA is 2 or more, there are XA number of R LA1 which may be the same or different from each other.

[0534] When XA is 2 or more, there are XA number of R LA2 which may be the same or different from each other.

[0535] -(C(R LA1 )(R LA2 ))- is preferably -CH2-, -CHF-, -CH(CF3)- or -CF2-.

[0536] Among them, the -(C(R - )(R LA1 )(R LA2 ))- directly bonded to A in the general formula (PB) is preferably -CH2-, -CHF-, -CH(CF3)- or -CF2-.

[0537] In the general formula (PB), the one directly bonded to A - -(C(R LA1 )(R LA2 ))- other than LA1 (R LA2 ))- is independently preferably -CH2-, -CHF- or -CF2-.

[0538] In the general formula (L), LB represents a single bond, an ester group (-COO-) or a sulfonyl group (-SO2-).

[0539] In the general formula (L), LC represents a single bond, an alkylene group, a cycloalkylene group or a group formed by combining these ("-alkylene-cycloalkylene-" etc.).

[0540] The above-mentioned alkylene group may be linear or branched.

[0541] The number of carbon atoms of the above-mentioned alkylene group is preferably 1 to 5, more preferably 1 to 2, and further preferably 1. The number of carbon atoms of the above-mentioned cycloalkylene group is preferably 3 to 15, more preferably 5 to 10.

[0542] The above-mentioned cycloalkylene group may be monocyclic or polycyclic.

[0543] As the above-mentioned cycloalkylene group, for example, norbornane diyl and adamantane diyl can be cited.

[0544] The substituent that the above-mentioned cycloalkylene group may have is preferably an alkyl group (which may be linear or branched. Preferably, the number of carbon atoms is 1 to 5).

[0545] One or more of the methylene groups of the cycloalkane ring constituting the above-mentioned cycloalkylene group may be substituted with a carbonyl carbon and / or a heteroatom (such as an oxygen atom).

[0546] When LC is "-alkylene-cycloalkylene-", the alkylene part preferably exists on the LB side.

[0547] When LB is a single bond, LC is preferably a single bond or a cycloalkylene group.

[0548] In the general formula (L), LD represents a single bond, an ether group (-O-), a carbonyl group (-CO-) or an ester group (-COO-).

[0549] In the general formula (L), LE represents a single bond or -(C(R LE1 )(R LE2 )) XE -.

[0550] The above-mentioned -(C(R LE1 )(R LE2 ))XE In the following formula, XE represents an integer of 1 or more, preferably 1 to 10, more preferably 1 to 3.

[0551] R LE1 and R LE2 each independently represents a hydrogen atom or a substituent.

[0552] When XE is 2 or more, there are XE number of Rs LE1 which may be the same or different from each other.

[0553] When XE is 2 or more, there are XE number of Rs LE2 which may be the same or different from each other.

[0554] Among them, -(C(R LE1 )(R LE2 ))- is preferably -CH2-. In the general formula (L), when LB, LC and LD are single bonds, LE is preferably also a single bond.

[0555] In the general formula (PB), A - represents an acid anion group.

[0556] The acid anion group is a group having an anionic atom.

[0557] Specifically, A - is preferably a group represented by any one of the general formulas (A-1) to (A-2).

[0558] [Chemical formula 44]

[0559]

[0560] In the general formulas (A-1) to (A-2), * represents the bonding position.

[0561] In the general formula (A-2), R A represents an organic group.

[0562] R A is preferably an alkyl group.

[0563] The above-mentioned alkyl group may be linear or branched.

[0564] The number of carbon atoms of the above-mentioned alkyl group is preferably 1 to 10, more preferably 1 to 5.

[0565] The substituent that the above-mentioned alkyl group may have is preferably a fluorine atom.

[0566] The above-mentioned alkyl group having a fluorine atom as a substituent may or may not be a perfluoroalkyl group.

[0567] In the general formula (PB), B - represents an acid anion group.

[0568] Specifically, B - is preferably a group represented by any one of general formulas (B-1) to (B-4).

[0569] B - is preferably a group represented by any one of general formulas (B-1) to (B-3), and more preferably a group represented by any one of general formulas (B-1) to (B-2).

[0570] [Chemical formula 45]

[0571]

[0572] In general formulas (B-1) to (B-4), * represents the bonding position.

[0573] In general formulas (B-1) to (B-4), R B represents an organic group.

[0574] R B is preferably cycloalkyl or alkyl.

[0575] When R B is cycloalkyl, the number of carbon atoms of the cycloalkyl is preferably 3 to 15, and more preferably 5 to 10.

[0576] The cycloalkyl may be monocyclic or polycyclic.

[0577] Examples of the cycloalkyl include norbornyl and adamantyl.

[0578] The substituent that the cycloalkyl may have is preferably alkyl (which may be linear or branched. Preferably, the number of carbon atoms is 1 to 5).

[0579] One or more of the carbon atoms of the ring member atoms of the cycloalkyl may be replaced by a carbonyl carbon atom.

[0580] When R B is alkyl, the alkyl may be linear or branched.

[0581] The number of carbon atoms of the alkyl is preferably 1 to 10, and more preferably 1 to 5.

[0582] The substituent that the alkyl may have is preferably cycloalkyl, fluorine atom or cyano group.

[0583] Examples of the cycloalkyl as the substituent can be the same cycloalkyls described when R B is cycloalkyl.

[0584] When the above alkyl group has a fluorine atom as the above substituent, the above alkyl group may or may not be a perfluoroalkyl group. When the above alkyl group has a fluorine atom as the above substituent, it is also preferred that part or all of the above alkyl group is a perfluoromethyl group.

[0585] In M1 of the compound represented by the general formula (PB) + and M2 + In the compounds represented by HA-L-BH in which M1 and M2 are each replaced by a hydrogen atom, the pKa of the group represented by HA is lower than the pKa of the group represented by BH.

[0586] More specifically, in the case of obtaining the acid dissociation constant of the compound represented by HA-L-BH, the pKa when "HA-L-BH" becomes "A - -L-BH" is defined as the "pKa of the group represented by HA". In addition, the pKa when "A - -L-BH" becomes "A - -L-B - " is defined as the "pKa of the group represented by BH".

[0587] The "pKa of the group represented by HA" and the "pKa of the group represented by BH" are obtained using "Package 1" or "Gaussian16", respectively.

[0588] Among them, the pKa of the group represented by HA is preferably -12.00 to 1.00, more preferably -7.00 to 0.50, and further preferably -5.00 to 0.00.

[0589] The pKa of the group represented by HB is preferably -4.00 to 14.00, more preferably -2.00 to 12.00, and further preferably -1.00 to 5.00.

[0590] The difference between the pKa of the group represented by HB and the pKa of the group represented by HA ("pKa of the group represented by HB" - "pKa of the group represented by HA") is preferably 0.10 to 20.00, more preferably 0.50 to 17.00, and further preferably 2.00 to 15.00.

[0591] As the compound represented by the above general formula (PB), an ionic compound (D) represented by the following general formula (PD) is also preferred.

[0592] (Other photoacid generators)

[0593] The resist composition may use other photoacid generators other than the above.

[0594] As other photoacid generators, for example, those represented by "M + Z- (M + represents a cation, and Z - represents an anion)” represents a compound (onium salt).

[0595] In the compound represented by “M + Z - ”, M + represents a cation, and the same cations as those in the general formula (PA-1) can be cited.

[0596] In the compound represented by “M + Z - ”, Z - represents an anion, and is preferably an anion with significantly low ability to cause nucleophilic reaction.

[0597] As the above-mentioned anion, for example, sulfonic acid anions (aliphatic sulfonic acid anions such as fluorinated alkylsulfonic acid anions, aromatic sulfonic acid anions, and camphorsulfonic acid anions), carboxylic acid anions (aliphatic carboxylic acid anions, aromatic carboxylic acid anions, and aralkyl carboxylic acid anions), and tris(alkylsulfonyl)methide anions can be cited.

[0598] The aliphatic moiety in the aliphatic sulfonic acid anion and the aliphatic carboxylic acid anion can be an alkyl group or a cycloalkyl group, and is preferably a linear or branched alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms.

[0599] The aromatic ring group in the aromatic sulfonic acid anion and the aromatic carboxylic acid anion is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group, a tolyl group, and a naphthyl group.

[0600] As substituents that the above-mentioned alkyl group, cycloalkyl group, and aryl group may have, for example, nitro group, halogen atoms such as fluorine atom, carboxylic acid group, hydroxyl group, amino group, cyano group, alkoxy group (preferably having 1 to 15 carbon atoms), cycloalkyl group (preferably having 3 to 15 carbon atoms), aryl group (preferably having 6 to 14 carbon atoms), alkoxycarbonyl group (preferably having 2 to 7 carbon atoms), acyl group (preferably having 2 to 12 carbon atoms), alkoxycarbonyloxy group (preferably having 2 to 7 carbon atoms), alkylthio group (preferably having 1 to 15 carbon atoms), alkylsulfonyl group (preferably having 1 to 15 carbon atoms), alkyliminosulfonyl group (preferably having 1 to 15 carbon atoms), aryloxysulfonyl group (preferably having 6 to 20 carbon atoms), alkylaryloxysulfonyl group (preferably having 7 to 20 carbon atoms), cycloalkylaryloxysulfonyl group (preferably having 10 to 20 carbon atoms), alkoxyalkoxy group (preferably having 5 to 20 carbon atoms), and cycloalkylalkoxyalkoxy group (preferably having 8 to 20 carbon atoms) can be cited.

[0601] The aralkyl group in the aralkylcarboxylic acid anion is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include benzyl, phenethyl, naphthylmethyl, naphthylethyl, and naphthylbutyl.

[0602] The alkyl group in the tris(alkylsulfonyl)methylide anion is preferably an alkyl group having 1 to 5 carbon atoms. Examples of the substituents of these alkyl groups include a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, an alkylthio group, an alkoxysulfonyl group, an aryloxysulfonyl group, and a cycloalkylaryloxysulfonyl group, and a fluorine atom or an alkyl group substituted with a fluorine atom is preferred.

[0603] As other non-nucleophilic anions, for example, phosphorus fluoride (e.g., PF6 - ), boron fluoride (e.g., BF4 - ), and antimony fluoride (e.g., SbF6 - ) can be mentioned.

[0604] The non-nucleophilic anion is preferably an aliphatic sulfonic acid anion in which at least the α-position of the sulfonic acid is substituted with a fluorine atom, an aromatic sulfonic acid anion substituted with a fluorine atom or a group having a fluorine atom, or a tris(alkylsulfonyl)methylide anion in which the alkyl group is substituted with a fluorine atom. Among them, a perfluoroaliphatic sulfonic acid anion (preferably having 4 to 8 carbon atoms) or a benzenesulfonic acid anion having a fluorine atom is more preferred, and a nonafluorobutanesulfonic acid anion, a perfluorooctanesulfonic acid anion, a pentafluorobenzenesulfonic acid anion, or a 3,5-bis(trifluoromethyl)benzenesulfonic acid anion is further preferred.

[0605] From the viewpoint of acid strength, in order to improve the sensitivity, it is preferred that the pKa of the acid generated is -1 or less.

[0606] Moreover, the non-nucleophilic anion is also preferably an anion represented by the following general formula (AN1).

[0607] [Chemical formula 46]

[0608]

[0609] In the formula, Xf each independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom.

[0610] R 1 and R 2 each independently represents a hydrogen atom, a fluorine atom, or an alkyl group, and when there are a plurality of Rs 1 and R 2 can be the same or different from each other.

[0611] L represents a divalent linking group, and when there are a plurality of Ls, they can be the same or different.

[0612] A represents a cyclic organic group.

[0613] x represents an integer from 1 to 20, y represents an integer from 0 to 10, and z represents an integer from 0 to 10.

[0614] The general formula (AN1) will be described in more detail.

[0615] The number of carbon atoms of the alkyl group in the alkyl group substituted by fluorine atoms of Xf is preferably 1 to 10, more preferably 1 to 4. Further, the alkyl group substituted by fluorine atoms of Xf is preferably a perfluoroalkyl group.

[0616] Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms. Examples of Xf include a fluorine atom, CF3, C2F5, C3F7, C4F9, CH2CF3, CH2CH2CF3, CH2C2F5, CH2CH2C2F5, CH2C3F7, CH2CH2C3F7, CH2C4F9, and CH2CH2C4F9. Among them, a fluorine atom or CF3 is preferred. In particular, it is preferred that both Xf are fluorine atoms.

[0617] R 1 and R 2 The alkyl group of may have a substituent (preferably a fluorine atom), and the number of carbon atoms in the substituent is preferably 1 to 4. The substituent is preferably a perfluoroalkyl group having 1 to 4 carbon atoms. R 1 and R 2 Examples of the alkyl group having a substituent of include CF3, C2F5, C3F7, C4F9, C5F 11 , C6F 13 , C7F 15 , C8F 17 , CH2CF3, CH2CH2CF3, CH2C2F5, CH2CH2C2F5, CH2C3F7, CH2CH2C3F7, CH2C4F9, and CH2CH2C4F9. Among them, CF3 is preferred.

[0618] R 1 and R 2 are preferably a fluorine atom or CF3.

[0619] x is preferably an integer from 1 to 10, more preferably an integer from 1 to 5.

[0620] y is preferably an integer from 0 to 4, more preferably 0.

[0621] z is preferably an integer from 0 to 5, more preferably an integer from 0 to 3.

[0622] As a divalent linking group for L, for example, -COO-, -CO-, -O-, -S-, -SO-, -SO2-, an alkylene group, a cycloalkylene group, an alkenylene group, and a linking group formed by linking a plurality of these can be cited, etc., and a linking group having 12 or less carbon atoms in total is preferred. Among them, -COO-, -CO- or -O- is preferred, and -COO- is more preferred.

[0623] The cyclic organic group of A is not particularly limited as long as it has a cyclic structure, and examples thereof include an alicyclic group, an aromatic ring group, and a heterocyclic group (including not only groups having aromaticity but also groups not having aromaticity).

[0624] The alicyclic group may be a monocyclic or polycyclic group, and monocyclic cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group are preferred. In addition, polycyclic cycloalkyl groups such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are also preferred. Among them, from the viewpoint of being able to suppress diffusion in the film in the post-exposure heating process and improving the MEEF (Mask Error Enhancement Factor), alicyclic groups having a bulky structure with 7 or more carbon atoms such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferred.

[0625] As the aromatic ring group, for example, a benzene ring, a naphthalene ring, a phenanthrene ring, an anthracene ring, etc. can be cited.

[0626] As the heterocyclic group, for example, groups derived from a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, a pyridine ring, etc. can be cited. Among them, groups derived from a furan ring, a thiophene ring, or a pyridine ring are preferred.

[0627] In addition, as the cyclic organic group, a lactone structure can also be cited, and as a specific example, a lactone structure represented by the aforementioned general formulas (LC1-1) to (LC1-22) can be cited.

[0628] The above-mentioned cyclic organic group may have a substituent. Examples of the substituent include an alkyl group (which may be linear or branched and may include a cyclic structure. Preferably having 1 to 12 carbon atoms), a cycloalkyl group (which may be either monocyclic or polycyclic, and when it is polycyclic, it may be a spiro ring. Preferably having 3 to 20 carbon atoms), an aryl group (preferably having 6 to 14 carbon atoms), a hydroxyl group, an alkoxy group, an ester group, an amide group, a urethane group, a urea group, a thioether group, a sulfonamide group, and a sulfonate group, etc. In addition, the carbon (carbon contributing to the formation of the ring) constituting the cyclic organic group may be a carbonyl carbon.

[0629] Moreover, the photoacid generator has a cationic part and an anionic part, and may be a betaine compound having a structure in which the two are connected by a covalent bond.

[0630] As a photoacid generator, paragraphs

[0368] to

[0377] of Japanese Patent Application Laid-Open No. 2014-41328 and paragraphs

[0240] to

[0262] of Japanese Patent Application Laid-Open No. 2013-228681 (paragraph

[0339] of the specification of U.S. Patent Application Publication No. 2015 / 004533 corresponding thereto) can be cited, and these contents are incorporated into the specification of the present application.

[0631] Moreover, the following compounds can be cited as preferred specific examples. In the following compounds, the anion and the cation can be arbitrarily exchanged when possible.

[0632] [Chemical formula 47]

[0633]

[0634] [Chemical formula 48]

[0635]

[0636] [Chemical formula 49]

[0637]

[0638] [Chemical formula 50]

[0639]

[0640] [Chemical formula 51]

[0641]

[0642] [Chemical formula 52]

[0643]

[0644] The content of the photoacid generator in the resist composition is not particularly limited, and from the viewpoint of more excellent effects of the present invention, it is preferably 5% by mass or more, more preferably 9% by mass or more, and still more preferably 15% by mass or more with respect to the total solid content of the composition. Moreover, the above content is preferably 40% by mass or less, more preferably 35% by mass or less, and still more preferably 30% by mass or less.

[0645] The photoacid generator can be used alone as one kind, or two or more kinds can be used.

[0646] <(C) A compound whose acid capturability is reduced by decomposition by irradiation with actinic rays or radiation, having an anionic acid capturability group, not having a nonionic acid capturability group, and being an ionic compound containing a fluorine atom in the anion part>

[0647] The resist composition contains, as an acid diffusion control agent, (C) a compound which is decomposed by irradiation with actinic rays or radiation to reduce its acid-capturing property, has an anionic acid-capturing group, does not have a nonionic acid-capturing group, and contains a fluorine atom in the anionic moiety (also referred to as ionic compound (C), photodecomposable quencher or photodecomposable quencher (C)).

[0648] Ionic compound (C) captures the acid generated from the photoacid generator (B) etc. during exposure and functions as a quencher to inhibit the reaction of the resin (A) in the unexposed portion due to the excess generated acid.

[0649] Ionic compound (C) is a compound that generates an acid which is weaker than the acid generated from the photoacid generator (B). That is, ionic compound (C) is a compound that generates an acid having a pKa larger than the acid generated from the photoacid generator (B).

[0650] The difference in pKa between the acid generated from ionic compound (C) and the acid generated from the photoacid generator (B) (the value obtained by subtracting the pKa of the acid generated from the photoacid generator (B) from the pKa of the acid generated from ionic compound (C)) is preferably 1.00 or more, preferably 1.00 to 10.00, more preferably 1.00 to 5.00, and still more preferably 1.00 to 3.00.

[0651] Moreover, the pKa of the acid generated from ionic compound (C) varies depending on the type of the photoacid generator (B) used. For example, it is preferably -4.00 to 14.00, more preferably -2.00 to 12.00, and still more preferably -1.00 to 5.00.

[0652] Ionic compound (C) contains a fluorine atom in the anionic moiety. Thereby, the interaction between the acid diffusion control agents can be weakened and aggregation can be inhibited.

[0653] Moreover, the acid-capturing group of ionic compound (C) is anionic and does not have a nonionic acid-capturing group such as an amino group that enhances aggregability. Thereby, aggregation can be further inhibited.

[0654] As ionic compound (C), among the compounds exemplified as the above photoacid generator (B) (preferably the compounds represented by the above general formula (PA-1), the compounds represented by the general formula (PB), the onium salts represented by M + Z-), a compound that does not have a nonionic acid-capturing group and contains a fluorine atom in the anionic moiety can be selectively used to make it a compound that generates an acid which is relatively weak compared to the acid generated from the photoacid generator (B) used.

[0655] The ionic compound (C) needs to contain a fluorine atom in the anion part, and preferably further contains a fluorine atom in the cation part.

[0656] The ionic compound (C) is preferably a compound represented by the following general formulas (C1) to (C3).

[0657] (Compound represented by general formula (C1))

[0658] [Chemical formula 53]

[0659] R C1 -L C1 -SO3 - M C + (C1)

[0660] In general formula (C1),

[0661] R C1 represents a cycloalkyl group or an aryl group.

[0662] L C1 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0663] Among them, at least one of R C1 and L C1 is substituted by a fluorine atom or a group having a fluorine atom.

[0664] M C + represents an organic cation.

[0665] In general formula (C1),

[0666] R C1 represents a cycloalkyl group or an aryl group.

[0667] As the cycloalkyl group when R C1 represents a cycloalkyl group, it is preferably a cycloalkyl group having 3 to 15 carbon atoms, more preferably a cycloalkyl group having 5 to 10 carbon atoms. The cycloalkyl group can be a monocyclic or polycyclic ring.

[0668] As the cycloalkyl group, for example, norbornyl, decahydronaphthyl, and adamantyl can be mentioned, and adamantyl is preferred.

[0669] As the aryl group when R C1 represents an aryl group, it is preferably an aryl group having 6 to 15 carbon atoms.

[0670] As the aryl group, for example, phenyl, naphthyl can be mentioned, and phenyl is preferred.

[0671] As R C1When there is a substituent, examples of the substituent include a fluorine atom, a group having a fluorine atom, a hydroxyl group, an alkyl group, a halogen atom other than a fluorine atom, etc.

[0672] As the group having a fluorine atom, a fluorine-substituted alkyl group or a fluorine-substituted cycloalkyl group is preferred.

[0673] As the fluorine-substituted alkyl group, a fluorinated alkyl group having 1 to 5 carbon atoms is preferred. Specifically, examples include a trifluoromethyl group, a pentafluoroethyl group, a nonafluorobutyl group, etc., and a trifluoromethyl group is preferred.

[0674] As the fluorine-substituted cycloalkyl group, a fluorinated cycloalkyl group having 3 to 15 carbon atoms is preferred. Specifically, examples include a fluorocyclohexyl group, a fluorocyclopentyl group, a fluoroadamantyl group, etc., and a fluorocyclohexyl group is preferred.

[0675] As the alkyl group, examples include a linear or branched alkyl group having 1 to 5 carbon atoms.

[0676] As the halogen atom other than a fluorine atom, examples include a chlorine atom, a bromine atom, and an iodine atom.

[0677] R C1 It is preferably a polycyclic cycloalkyl group or an aryl group substituted with a fluorine atom or a group having a fluorine atom.

[0678] In general formula (C1),

[0679] L C1 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0680] As L C1 When it represents an alkylene group, examples of the alkylene group include a linear or branched alkylene group having 1 to 20 carbon atoms.

[0681] As the linear or branched alkylene group having 1 to 20 carbon atoms, examples include a methylene group, a vinyl group, a n-propylene group, an isopropyl group, a n-butylene group, a n-pentylene group, etc., and a methylene group, a vinyl group, a n-propylene group or a n-butylene group is preferred.

[0682] As L C1 When it represents a cycloalkylene group, examples of the cycloalkylene group include a monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms.

[0683] As the monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms, examples include an adamantylene group, a cyclohexylene group, a cyclopentylene group, a cycloheptylene group, a norbornylene group, etc., and an adamantylene group, a cyclohexylene group, a norbornylene group are preferred.

[0684] As L C1 When there is a substituent, examples of the substituent include the above-mentioned R C1Substituent when there is a substituent.

[0685] L C1 It is preferably a single bond or an alkylene group, and more preferably a single bond or an n-butylene group.

[0686] In the general formula (C1),

[0687] M C + Represents an organic cation.

[0688] M C + Preferred are cations represented by the following general formula (ZcI) or general formula (ZcII).

[0689] [Chemical formula 54]

[0690]

[0691] In the general formula (ZcI),

[0692] R C01 , R C02 and R C03 Each independently represents an organic group.

[0693] [Chemical formula 55]

[0694] R C04 -I + -R C05 (ZcII)

[0695] In the general formula (ZcII),

[0696] R C04 and R C05 Each independently represents an aryl group, an alkyl group or a cycloalkyl group.

[0697] In the above general formula (ZcI),

[0698] R C01 , R C02 and R C03 Each independently represents an organic group.

[0699] As R C01 , R C02 and R C03 The number of carbon atoms of the organic group is usually 1 to 30, preferably 1 to 20. C01 ~R C03 Two of them may be bonded to form a ring structure, and may contain an oxygen atom, a sulfur atom, an ester group, an amide group, or a carbonyl group in the ring. C01 ~R C03Groups formed by bonding two of them, examples thereof include alkylene groups (e.g., butylene, pentylene, etc.) and -CH2-CH2-O-CH2-CH2-.

[0700] As the cation in the general formula (ZcI), for example, the cations (ZaI-1), (ZaI-2) in the above-mentioned photoacid generator (B), the cation represented by the general formula (ZaI-3b) (cation (ZaI-3b)), and the cation represented by the general formula (ZaI-4b) (cation (ZaI-4b)) can be cited.

[0701] In the general formula (ZcII),

[0702] R C04 and R C05 each independently represent an aryl group, an alkyl group, or a cycloalkyl group.

[0703] R C04 and R C05 The aryl group of R C04 and R C05 is preferably a phenyl group or a naphthyl group, more preferably a phenyl group. The aryl group of R

[0704] R C04 and R C05 The alkyl group and cycloalkyl group of can be a linear alkyl group having 1 to 10 carbon atoms or a branched alkyl group having 3 to 10 carbon atoms (e.g., methyl, ethyl, propyl, butyl, or pentyl) or a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, or norbornyl).

[0705] R C04 and R C05 The aryl group, alkyl group, and cycloalkyl group of can each independently have a substituent. As the substituents that the aryl group, alkyl group, and cycloalkyl group of R C04 and R C05 can have, for example, an alkyl group (e.g., having 1 to 15 carbon atoms), a cycloalkyl group (e.g., having 3 to 15 carbon atoms), an aryl group (e.g., having 6 to 15 carbon atoms), an alkoxy group (e.g., having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group, etc.

[0706] (Compound represented by the general formula (C2))

[0707] [Chemical formula 56]

[0708] R C2 -L C2 -CO2 - MC + (C2)

[0709] In general formula (C2),

[0710] R C2 represents a cycloalkyl group or an aryl group.

[0711] L C2 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0712] Among them, R C2 and L C2 at least one of which is substituted with a fluorine atom or a group having a fluorine atom.

[0713] M C + represents an organic cation.

[0714] In general formula (C2),

[0715] R C2 represents a cycloalkyl group or an aryl group.

[0716] As the cycloalkyl group when R C2 represents a cycloalkyl group, it is preferably a cycloalkyl group having 3 to 15 carbon atoms, more preferably a cycloalkyl group having 5 to 10 carbon atoms. The cycloalkyl group can be monocyclic or polycyclic.

[0717] As the cycloalkyl group, for example, norbornyl, decahydronaphthyl, and adamantyl can be mentioned, and adamantyl is preferred.

[0718] As the aryl group when R C2 represents an aryl group, it is preferably an aryl group having 6 to 15 carbon atoms.

[0719] As the aryl group, for example, phenyl, naphthyl can be mentioned, and phenyl is preferred.

[0720] As the substituent when R C2 has a substituent, the substituents in R in the above general formula (C1) can be mentioned C1 when it has a substituent.

[0721] R C2 is preferably a polycyclic cycloalkyl group, a polycyclic cycloalkyl group substituted with a fluorine atom or a group having a fluorine atom, or an aryl group substituted with a fluorine atom or a group having a fluorine atom, and more preferably adamantyl or a phenyl group substituted with a fluorine atom or a group having a fluorine atom.

[0722] In general formula (C2),

[0723] L C2 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0724] As L C2 When representing an alkylene group, the alkylene group may be a linear or branched alkylene group having 1 to 20 carbon atoms.

[0725] As the linear or branched alkylene group having 1 to 20 carbon atoms, methylene, vinyl, n-propylene, isopropyl, n-butylene, n-pentylene, etc. may be mentioned, and methylene, vinyl, n-propylene or n-butylene is preferred.

[0726] As L C2 When representing a cycloalkylene group, the cycloalkylene group may be a monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms.

[0727] As the monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms, adamantylene, cyclohexylene, cyclopentylene, cycloheptylene, norbornylene, etc. may be mentioned, and adamantylene, cyclohexylene, norbornylene are preferred.

[0728] As L C2 When having a substituent, the substituent may be the above-mentioned R C2 The substituent when having a substituent.

[0729] When the above-mentioned R C2 represents an aryl group, L C2 is preferably a single bond.

[0730] When the above-mentioned R C2 represents a cycloalkyl group, L C2 is preferably an alkylene group, -O-, -C(=O)- or a divalent linking group formed by combining these, and is preferably an alkylene group, -O-, -C(=O)- or a divalent linking group formed by combining these and substituted with a fluorine atom or a group having a fluorine atom.

[0731] M C + represents an organic cation.

[0732] M C + is preferably a cation represented by the above general formula (ZcI) or the above general formula (ZcII).

[0733] (Compound represented by general formula (C3))

[0734] [Chemical formula 57]

[0735]

[0736] In general formula (C3),

[0737] A C31 and AC32 each independently represents -SO2-R PC1 or -CO-R PC2 .

[0738] R PC1 and R PC2 represent organic groups.

[0739] Among them, A C31 and A C32 at least one of which is substituted by a fluorine atom or a group having a fluorine atom.

[0740] M C + represents an organic cation.

[0741] In the general formula (C3), A C31 and A C32 each independently represents -SO2-R PC1 or -CO-R PC2 .

[0742] R PC1 and R PC2 represent organic groups.

[0743] R PC1 and R PC2 are preferably respectively represented by -L C31 -R C31 and -L C32 -R C32 .

[0744] R C31 and R C32 each independently represents an alkyl group or a cycloalkyl group.

[0745] As the alkyl group for R C31 or R C32 when it represents an alkyl group, it is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms.

[0746] As the alkyl group, for example, methyl, ethyl, n-propyl, isopropyl, etc. can be cited, preferably methyl or ethyl, more preferably methyl.

[0747] As the cycloalkyl group for R C31 or R C32 when it represents a cycloalkyl group, it is preferably a cycloalkyl group having 3 to 15 carbon atoms, more preferably a cycloalkyl group having 5 to 10 carbon atoms. The cycloalkyl group can be a monocyclic or polycyclic group.

[0748] As the cycloalkyl group, for example, cyclohexyl, norbornyl, decahydronaphthyl and adamantyl can be cited, preferably cyclohexyl or adamantyl.

[0749] One or more of the carbon atoms as the ring member atoms of the above cycloalkyl group may be substituted with a carbonyl carbon atom.

[0750] As R C31 or R C32 When having a substituent, the substituent may be the R in the above general formula (C1) C1 When having a substituent.

[0751] R C31 and R C32 are each independently preferably an alkyl group, an alkyl group or a cycloalkyl group substituted with a fluorine atom or a group having a fluorine atom, more preferably a methyl group, a trifluoromethyl group, a cyclohexyl group or an adamantyl group.

[0752] L C31 and L C32 each independently represent a single bond or a divalent linking group.

[0753] L C31 and L C32 each independently preferably represent a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)- or a divalent linking group formed by combining these.

[0754] As the alkylene group when L C31 or L C32 represents an alkylene group, there may be mentioned a linear or branched alkylene group having 1 to 20 carbon atoms.

[0755] As the linear or branched alkylene group having 1 to 20 carbon atoms, there may be mentioned a methylene group, a vinyl group, a n-propylene group, an isopropyl group, a n-butylene group, a n-pentylene group, etc., preferably a methylene group, a vinyl group, a n-propylene group or a n-butylene group.

[0756] As the cycloalkylene group when L C31 or L C32 represents a cycloalkylene group, there may be mentioned a monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms.

[0757] As the monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms, there may be mentioned an adamantylene group, a cyclohexylene group, a cyclopentylene group, a cycloheptylene group, a norbornylene group, etc., preferably an adamantylene group, a cyclohexylene group, a norbornylene group.

[0758] As the substituent when L C31 or L C32 has a substituent, there may be mentioned the above R C31 or R C32 When having a substituent.

[0759] L C31 and L C32Each is independently preferably a single bond, an alkylene group or a fluorine-substituted alkylene group.

[0760] In general formula (C3), M C + represents an organic cation.

[0761] M C + is preferably a cation represented by the above general formula (ZcI) or general formula (ZcII).

[0762] As a preferred specific example of the above ionic compound (C), the following compounds can be cited. In the following compounds, the anion and the cation can be arbitrarily exchanged if possible.

[0763] [Chemical formula 58]

[0764]

[0765] [Chemical formula 59]

[0766]

[0767] [Chemical formula 60]

[0768]

[0769] The ionic compound (C) is also preferably represented by the general formula (PD) described later.

[0770] The content of the ionic compound (C) in the resist composition is not particularly limited. From the viewpoint of more excellent effects of the present invention, it is preferably 5% by mass or more, more preferably 9% by mass or more, and further preferably 15% by mass or more based on the total solid content of the composition. Moreover, the above content is preferably 40% by mass or less, more preferably 35% by mass or less, and further preferably 30% by mass or less.

[0771] The ionic compound (C) can be used alone or in combination of two or more.

[0772] <An ionic compound (D) that generates an acid upon irradiation with actinic rays or radiation, has its acid-capturing property reduced by irradiation with actinic rays or radiation, has an anionic acid-capturing group, does not have a nonionic acid-capturing group, and contains a fluorine atom in the anion part.

[0773] In the resist composition of the present invention, the photoacid generator (B) and the ionic compound (C) may be the same compound. In this case, the compound is a compound that generates an acid upon irradiation with actinic rays or radiation and decomposes upon irradiation with actinic rays or radiation to reduce acid capturability, and has an anionic acid capturability group, does not have a nonionic acid capturability group, and contains a fluorine atom in the anionic part, an ionic compound (D) (also referred to as ionic compound (D), photoacid generator-linked quencher, or photoacid generator-linked quencher (D)). In other words, the ionic compound (D) is a compound having a structure corresponding to the function of the photoacid generator (B) and a structure corresponding to the function of the ionic compound (C).

[0774] In addition, as described above, in the present invention, the ionic compound (C) is a compound that generates an acid weaker than the acid generated from the photoacid generator (B). That is, the ionic compound (C) is a compound that generates an acid having a pKa greater than the acid generated from the photoacid generator (B). When the photoacid generator (B) and the ionic compound (C) are the same ionic compound (D), the pKa of the acid generated by the structure corresponding to the function of the ionic compound (C) in the ionic compound (D) is greater than the pKa of the acid generated by the structure corresponding to the function of the photoacid generator (B).

[0775] (Compound represented by general formula (PD))

[0776] The ionic compound (D) is preferably a compound represented by the following general formula (PD).

[0777] [Chemical formula 61]

[0778] M D1 + A D1 - -L D -B D1 - M D2 + (PD)

[0779] In general formula (PD),

[0780] M D1 + and M D2 + each independently represents an organic cation.

[0781] L D represents a divalent organic group.

[0782] A D1 - and B D1- Each independently represents an acid anion group.

[0783] Among them, in the M of the compound represented by the general formula (PD) D1 + and M D2 + HA in which each is substituted by a hydrogen atom D1 -L D -B D1 In the compound represented by H, the pKa of the group represented by HA D1 is lower than the pKa of the group represented by B D1 H.

[0784] The compound represented by the general formula (PD) contains, in one molecule, a structure having a function corresponding to the photoacid generator (B) (equivalent to the part of "M D1 + A D1 - -") and a structure having a function corresponding to the ionic compound (C) (equivalent to the part of "-B D1 - M D2 + "), so in the resist film, the existence ratio of each of the above structures can be made constant.

[0785] Therefore, the inventors of the present invention speculate that even when the resist film is exposed, the amount and diffusion of the acid generated in the resist film are likely to become uniform, and the width of the pattern obtained after development is also stable.

[0786] In the general formula (PD), M D1 + and M D2 + Each independently represents an organic cation.

[0787] M D1 + and M D2 + The organic cations of are each independently preferably a cation represented by the above general formula (ZcI) or general formula (ZcII).

[0788] In the general formula (PD), L D represents a divalent organic group.

[0789] As the above divalent organic group, for example, -COO-, -CONH-, -CO-, alkylene (preferably having 1 to 6 carbon atoms. It may be linear or branched), cycloalkylene (preferably having 3 to 15 carbon atoms), alkenylene (preferably having 2 to 6 carbon atoms), and a divalent linking group formed by combining a plurality of them, etc. can be cited.

[0790] One or more of the methylene groups of the cycloalkane ring constituting the above-mentioned sub-cycloalkyl group may be substituted with a carbonyl carbon and / or an oxygen atom.

[0791] These divalent linking groups further preferably have a group selected from the group consisting of -O-, -S-, -SO-, and -SO2-.

[0792] Among them, L D is preferably a group represented by the following general formula (LD).

[0793] *A D -L D A-L D B-L D C-L D D-L D E-*B D (LD)

[0794] In the general formula (LD), *A D represents the bonding position to A in the general formula (PD) D1 - with.

[0795] In the general formula (LD), *B D represents the bonding position to B in the general formula (PD) D1 - with.

[0796] In the general formula (LD), L D A represents -(C(R D LA1 )(R D LA2 )) XA D -.

[0797] The above XA D represents an integer of 1 or more, preferably 1 to 10, more preferably 1 to 3.

[0798] R D LA1 and R D LA2 each independently represent a hydrogen atom or a substituent.

[0799] R D LA1 and R D LA2 The substituents of are each independently preferably a fluorine atom or a fluorinated alkyl group, more preferably a fluorine atom or a perfluoroalkyl group, and further preferably a fluorine atom or a perfluoromethyl group.

[0800] When XA DWhen it is 2 or more, there are XA D of R D LA1 They may be the same or different respectively.

[0801] When XA D is 2 or more, there are XA D of R D LA2 They may be the same or different respectively.

[0802] -(C(R D LA1 )(R D LA2 ))- is preferably -CH2-, -CHF-, -CH(CF3)- or -CF2-.

[0803] Among them, the -(C(R D1 - directly bonded to A in the general formula (PD) D LA1 )(R D LA2 ))- is preferably -CH2-, -CHF-, -CH(CF3)- or -CF2-.

[0804] The -(C(R D1 - directly bonded to A in the general formula (PD) D LA1 )(R D LA2 ))- other than D LA1 )(R D LA2 ))- are each independently preferably -CH2-, -CHF- or -CF2-.

[0805] In the general formula (LD), L D B represents a single bond, an ester group (-COO-) or a sulfonyl group (-SO2-).

[0806] In the general formula (LD), L D C represents a single bond, an alkylene group, a cycloalkylene group or a group formed by combining these ("-alkylene-cycloalkylene-" etc.).

[0807] The above-mentioned alkylene group may be linear or branched.

[0808] The number of carbon atoms of the above-mentioned alkylene group is preferably 1 to 5, more preferably 1 to 2, and further preferably 1. The number of carbon atoms of the above-mentioned cycloalkylene group is preferably 3 to 15, more preferably 5 to 10.

[0809] The above sub-cycloalkyl group can be monocyclic or polycyclic.

[0810] As the above sub-cycloalkyl group, for example, norbornane diyl and adamantane diyl can be cited.

[0811] The substituent that the above sub-cycloalkyl group can have is preferably an alkyl group (which can be linear or branched. Preferably, the number of carbon atoms is 1 to 5).

[0812] One or more of the methylene groups of the cycloalkane ring constituting the above sub-cycloalkyl group can be substituted with a carbonyl carbon and / or a heteroatom (such as an oxygen atom).

[0813] When L D C is "-alkylene-sub-cycloalkyl-", the alkylene part preferably exists on the L D B side.

[0814] When L D B is a single bond, L D C is preferably a single bond or a sub-cycloalkyl group.

[0815] In the general formula (LD), L D D represents a single bond, an ether group (-O-), a carbonyl group (-CO-), or an ester group (-COO-).

[0816] In the general formula (LD), L D E represents a single bond or -(C(R D LE1 )(R D LE2 )) XE D -.

[0817] The above -(C(R D LE1 )(R D LE2 )) XE D In - the XE D represents an integer of 1 or more, preferably 1 to 10, more preferably 1 to 3.

[0818] R D LE1 and R D LE2 each independently represents a hydrogen atom or a substituent.

[0819] When XE D is 2 or more, there are XE D number of R D LE1 can be the same or different from each other.

[0820] When XE DWhen it is 2 or more, there are XE D R's of D D LE2 They can be the same or different respectively.

[0821] Among them, -(C(R D LE1 )(R D LE2 ))- is preferably -CH2-. In the general formula (L D ), when L D B, L D C and L D D are single bonds, it is preferred that L D E is also a single bond.

[0822] In the general formula (PD), A D1 - represents an acid anion group.

[0823] The acid anion group is a group having an anionic atom.

[0824] Specifically, A D1 - is preferably a group represented by any one of the general formulas (AD-1) to (AD-2).

[0825] [Chemical formula 62]

[0826]

[0827] In the general formulas (AD-1) to (AD-2), * represents the bonding position.

[0828] In the general formula (AD-2), R AD represents an organic group.

[0829] R AD is preferably an alkyl group.

[0830] The above alkyl group can be linear or branched.

[0831] The number of carbon atoms of the above alkyl group is preferably 1 to 10, more preferably 1 to 5.

[0832] The substituent that the above alkyl group can have is preferably a fluorine atom.

[0833] The above alkyl group having a fluorine atom as a substituent may or may not be a perfluoroalkyl group.

[0834] In the general formula (PD), B D1 - represents a group represented by any one of the general formulas (BD-1) to (BD-4).

[0835] BD1 - Preferably a group represented by any one of general formulas (BD-1) to (BD-3), more preferably a group represented by any one of general formulas (BD-1) to (BD-2).

[0836] [Chemical formula 63]

[0837]

[0838] In general formulas (BD-1) to (BD-4),

[0839] R BD Each independently represents an organic group.

[0840] L BD Each independently represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0841] * represents the bonding position.

[0842] R BD Preferably an alkyl group, a cycloalkyl group, or an aryl group.

[0843] As R BD When representing an alkyl group, the alkyl group is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms.

[0844] As the alkyl group, for example, methyl, ethyl, n-propyl, isopropyl, etc. can be cited, preferably methyl or ethyl, more preferably methyl.

[0845] As R BD When representing a cycloalkyl group, the cycloalkyl group is preferably a cycloalkyl group having 3 to 15 carbon atoms, more preferably a cycloalkyl group having 5 to 10 carbon atoms. The cycloalkyl group can be monocyclic or polycyclic.

[0846] As the cycloalkyl group, for example, cyclopentyl, norbornyl, decahydronaphthyl, and adamantyl can be cited.

[0847] As R BD When representing an aryl group, the aryl group is preferably an aryl group having 6 to 15 carbon atoms.

[0848] As the aryl group, for example, phenyl, naphthyl can be cited, preferably phenyl.

[0849] As R BD When having a substituent, the substituent can be the R in the above general formula (C1) C1 When having a substituent.

[0850] L BDRepresents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these.

[0851] As L BD When representing an alkylene group, the alkylene group can be a linear or branched alkylene group having 1 to 20 carbon atoms.

[0852] As a linear or branched alkylene group having 1 to 20 carbon atoms, examples include a methylene group, a vinyl group, a n-propylene group, an isopropyl group, a n-butylene group, a n-pentylene group, etc., and preferably a methylene group, a vinyl group, a n-propylene group, or a n-butylene group.

[0853] As L BD When representing a cycloalkylene group, the cycloalkylene group can be a monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms.

[0854] As a monocyclic or polycyclic cycloalkylene group having 3 to 20 carbon atoms, examples include an adamantylene group, a cyclohexylene group, a cyclopentylene group, a cycloheptylene group, a norbornylene group, etc., and preferably an adamantylene group, a cyclohexylene group, a norbornylene group.

[0855] As L BD When having a substituent, the substituent can be the above-mentioned R BD The substituent when having a substituent.

[0856] L BD Preferably a single bond, a methylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these, and more preferably a single bond or a methylene group.

[0857] In the compound represented by the general formula (PD) for M D1 + And M D2 + Respectively substituted by a hydrogen atom, HA D1 -L D -B D1 In the compound represented by H, the pKa of the group represented by HA D1 Is lower than the pKa of the group represented by B D1 H.

[0858] More specifically, when calculating the acid dissociation constant of the compound represented by HA D1 -L D -B D1 H, when "HA D1 -L D -B D1 H" becomes "A D1 - -L D -B D1The pKa of “HA D1 when it is “H” is set as “the pKa of the group represented by HA D1 - -L D -B D1 H” becomes “A D1 - -L D -B D1 - ”, and the pKa of “B D1 when it is “H” is set as “the pKa of the group represented by B

[0859] “The pKa of the group represented by HA D1 ” and “the pKa of the group represented by B D1 H” are obtained using “Package 1” or “Gaussian16” respectively as described above.

[0860] Among them, the pKa of the group represented by HA D1 is preferably -12.00 to 1.00, more preferably -7.00 to 0.50, and further preferably -5.00 to 0.00.

[0861] The pKa of the group represented by B D1 H is preferably -4.00 to 14.00, more preferably -2.00 to 12.00, and further preferably -1.00 to 5.00.

[0862] The difference between the pKa of the group represented by B D1 H and the pKa of the group represented by HA D1 (“the pKa of the group represented by B D1 H” - “the pKa of the group represented by HA D1 ”) is preferably 0.10 to 20.00, more preferably 0.50 to 17.00, and further preferably 2.00 to 15.00.

[0863] The following are preferred specific examples of the compounds corresponding to the ionic compound (D).

[0864] [Chemical formula 64]

[0865]

[0866] The content of the ionic compound (D) in the resist composition is not particularly limited. From the viewpoint of more excellent effects of the present invention, it is preferably 5% by mass or more, more preferably 9% by mass or more, and further preferably 15% by mass or more, relative to the total solid content of the composition. Moreover, the above content is preferably 40% by mass or less, more preferably 35% by mass or less, and further preferably 30% by mass or less.

[0867] The ionic compound (D) can be used alone or in combination of two or more kinds.

[0868] The resist composition of the present invention preferably further contains at least one of a photoacid generator (B) and an ionic compound (C) in addition to the ionic compound (D).

[0869] Specific examples of the form of inclusion of the compound corresponding to the photoacid generator (B) or the ionic compound (C) in the resist composition of the present invention are as follows.

[0870] (i) Photoacid generator (B) other than ionic compound (D) + Ionic compound (C) other than ionic compound (D)

[0871] (ii) Ionic compound (D)

[0872] (iii) Ionic compound (D) + Photoacid generator (B) other than ionic compound (D)

[0873] (iv) Ionic compound (D) + Ionic compound (C) other than ionic compound (D)

[0874] (v) Ionic compound (D) + Photoacid generator (B) other than ionic compound (D) + Ionic compound (C) other than ionic compound (D)

[0875] In the above (iii), the ionic compound (D) needs to function as the ionic compound (C). In this case, the pKa of the acid generated from the structure having the function equivalent to the ionic compound (C) in the ionic compound (D) is greater than the pKa of the acid generated from the photoacid generator (B).

[0876] In the above (iv), the ionic compound (D) needs to function as the photoacid generator (B). In this case, the pKa of the acid generated from the ionic compound (C) is greater than the pKa of the acid generated from the structure having the function equivalent to the photoacid generator (B) in the ionic compound (D).

[0877] In the above (v), the ionic compound (D) can function as the photoacid generator (B) or as the ionic compound (C). When functioning as the photoacid generator (B), the pKa of the acid generated from the ionic compound (C) is greater than the pKa of the acid generated from the structure having the function equivalent to the photoacid generator (B) in the ionic compound (D). When functioning as the ionic compound (C), the pKa of the acid generated from the structure having the function equivalent to the ionic compound (C) in the ionic compound (D) is greater than the pKa of the acid generated from the photoacid generator (B).

[0878] <Other acid diffusion control agent (E)>

[0879] Within the range that does not hinder the effects of the present invention, the resist composition may further contain an acid diffusion control agent other than the ionic compound (C) and the ionic compound (D) (also referred to as other acid diffusion control agent (E), acid diffusion control agent (E)). The acid diffusion control agent acts as a quencher that captures the acid generated by the photoacid generator and plays a role in controlling the acid diffusion phenomenon in the resist film.

[0880] The acid diffusion control agent (E) can be, for example, a basic compound.

[0881] The basic compound is preferably a compound having a structure represented by the following general formula (A) to general formula (E).

[0882] [Chemical formula 65]

[0883]

[0884] In general formula (A) and general formula (E), R 200 , R 201 and R 202 may be the same or different and represent a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), a cycloalkyl group (preferably having 3 to 20 carbon atoms), or an aryl group (preferably having 6 to 20 carbon atoms). Here, R 201 and R 202 may be bonded to each other to form a ring.

[0885] Regarding the above alkyl group, the alkyl group having a substituent is preferably an aminoalkyl group having 1 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms, or a cyanoalkyl group having 1 to 20 carbon atoms.

[0886] R 203 , R 204 , R 205 and R 206 may be the same or different and represent an alkyl group having 1 to 20 carbon atoms.

[0887] The alkyl groups in these general formula (A) and general formula (E) are more preferably unsubstituted.

[0888] As the basic compound, guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine (the alkyl moiety may be linear or branched and may be partially substituted with an ether group and / or an ester group. The total number of all atoms other than the hydrogen atoms in the alkyl moiety is preferably 1 to 17), piperidine, etc. are preferable. Among them, compounds having an imidazole structure, a diazabicyclic structure, an oxonium hydroxide structure, a carboxonium structure, a trialkylamine structure, an aniline structure or a pyridine structure, alkylamine derivatives having a hydroxyl group and / or an ether bond, aniline derivatives having a hydroxyl group and / or an ether bond, etc. are more preferable.

[0889] As the compound having an imidazole structure, for example, imidazole, 2,4,5-triphenylimidazole, benzimidazole, etc. can be cited. As the compound having a diazabicyclic structure, for example, 1,4-diazabicyclo[2,2,2]octane, 1,5-diazabicyclo[4,3,0]non-5-ene, 1,8-diazabicyclo[5,4,0]undec-7-ene, etc. can be cited. As the compound having an oxonium hydroxide structure, for example, triarylsulfonium hydroxide, benzoyl sulfonium hydroxide, and sulfonium hydroxide having a 2-oxoalkyl can be cited. Specifically, triphenylsulfonium hydroxide, tris(tert-butylphenyl)sulfonium hydroxide, bis(tert-butylphenyl)iodonium hydroxide, benzoylthiophenium acetate, 2-oxopropylthiophenium hydroxide, etc. can be cited. As the compound having a carboxonium structure, it is a compound in which the anionic part of the compound having an oxonium hydroxide structure becomes a carboxylic acid ester. For example, acetate, adamantane-1-carboxylate, perfluoroalkyl carboxylate, etc. can be cited. As the compound having a trialkylamine structure, for example, tri(n-butyl)amine, tri(n-octyl)amine, etc. can be cited. As the aniline compound, for example, 2,6-diisopropylaniline, N,N-dimethylaniline, N,N-dibutylaniline, N,N-dihexylaniline, etc. can be cited. As the alkylamine derivative having a hydroxyl group and / or an ether bond, for example, ethanolamine, diethanolamine, triethanolamine, tris(methoxyethoxyethyl)amine, (HO-C2H4-O-C2H4)2N(-C3H6-O-CH3), etc. can be cited. As the aniline derivative having a hydroxyl group and / or an ether bond, for example, N,N-bis(hydroxyethyl)aniline, etc. can be cited.

[0890] As the basic compound, amine compounds having a phenoxy group and ammonium salt compounds having a phenoxy group can be preferably selected.

[0891] As the amine compound, for example, primary, secondary and tertiary amine compounds can be used, and an amine compound having at least one alkyl group bonded to the nitrogen atom is preferable. The amine compound is more preferably a tertiary amine compound. In the amine compound, as long as at least one alkyl group (preferably having 1 to 20 carbon atoms) is bonded to the nitrogen atom, in addition to the alkyl group, a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (preferably having 6 to 12 carbon atoms) may also be bonded to the nitrogen atom.

[0892] Further, the amine compound preferably has an oxyalkylene group. The number of oxyalkylene groups in the molecule is preferably 1 or more, more preferably 3 to 9, and still more preferably 4 to 6. Among the oxyalkylene groups, oxyethylene group (-CH2CH2O-) or oxypropylene group (-CH(CH3)CH2O- or CH2CH2CH2O-) is preferred, and oxyethylene group is more preferred.

[0893] Examples of the ammonium salt compound include primary, secondary, tertiary and quaternary ammonium salt compounds, and an ammonium salt compound in which at least one alkyl group is bonded to a nitrogen atom is preferred. In the ammonium salt compound, at least one alkyl group (preferably having 1 to 20 carbon atoms) is bonded to the nitrogen atom, and in addition to the alkyl group, a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (preferably having 6 to 12 carbon atoms) may also be bonded to the nitrogen atom.

[0894] The ammonium salt compound preferably has an oxyalkylene group. The number of oxyalkylene groups in the molecule is preferably 1 or more, more preferably 3 to 9, and still more preferably 4 to 6. Among the oxyalkylene groups, oxyethylene group (-CH2CH2O-) or oxypropylene group (-CH(CH3)CH2O- or CH2CH2CH2O-) is preferred, and oxyethylene group is more preferred.

[0895] Examples of the anion of the ammonium salt compound include a halogen atom, a sulfonate, a borate, a phosphate, etc. Among them, a halogen atom or a sulfonate is preferred. The halogen atom is preferably a chlorine atom, a bromine atom or an iodine atom. The sulfonate is preferably an organic sulfonate having 1 to 20 carbon atoms. Examples of the organic sulfonate include an alkyl sulfonate and an aryl sulfonate having 1 to 20 carbon atoms. The alkyl group of the alkyl sulfonate may have a substituent, and examples of the substituent include a fluorine atom, a chlorine atom, a bromine atom, an alkoxy group, an acyl group and an aromatic ring group. Examples of the alkyl sulfonate include methanesulfonate, ethanesulfonate, butanesulfonate, hexanesulfonate, octanesulfonate, benzylsulfonate, trifluoromethanesulfonate, pentafluoroethanesulfonate and nonafluorobutanesulfonate. Examples of the aryl group of the aryl sulfonate include a benzene ring group, a naphthalene ring group and an anthracene ring group. The substituent that the benzene ring group, the naphthalene ring group and the anthracene ring group may have is preferably a linear or branched alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms. Examples of the linear or branched alkyl group and the cycloalkyl group include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, a n-hexyl group and a cyclohexyl group. Examples of other substituents include an alkoxy group having 1 to 6 carbon atoms, a halogen atom, a cyano group, a nitro group, an acyl group and an acyloxy group.

[0896] The amine compound having a phenoxy group and the ammonium salt compound having a phenoxy group refer to a compound having a phenoxy group at the end of the alkyl group of the amine compound or the ammonium salt compound on the side opposite to the nitrogen atom.

[0897] As substituents of the phenoxy group, for example, alkyl groups, alkoxy groups, halogen atoms, cyano groups, nitro groups, carboxylic acid groups, carboxylic acid ester groups, sulfonic acid ester groups, aryl groups, aralkyl groups, acyloxy groups, aryloxy groups, etc. can be cited. The substitution position of the substituent can be any one of the 2nd to 6th positions. The number of substituents can be any one of 1 to 5.

[0898] Preferably, there is at least one oxyalkylene group between the phenoxy group and the nitrogen atom. The number of oxyalkylene groups in the molecule is preferably 1 or more, more preferably 3 to 9, and further preferably 4 to 6. Among the oxyalkylene groups, oxyethylene group (-CH2CH2O-) or oxypropylene group (-CH(CH3)CH2O- or CH2CH2CH2O-) is preferred, and oxyethylene group is more preferred.

[0899] The amine compound having a phenoxy group is obtained by the following method: After heating a primary or secondary amine having a phenoxy group and a haloalkyl ether and reacting them, an aqueous solution of a strong base (for example, sodium hydroxide, potassium hydroxide, tetraalkylammonium, etc.) is added to the reaction system, and the reaction product is further extracted using an organic solvent (for example, ethyl acetate, chloroform, etc.). Or, it is obtained by the following method: After heating a primary or secondary amine and a haloalkyl ether having a phenoxy group at the terminal and reacting them, an aqueous solution of a strong base is added to the reaction system, and the reaction product is further extracted using an organic solvent.

[0900] (A compound (PA) that generates a proton-accepting functional group and decomposes upon irradiation with actinic rays or radiation, thereby reducing, disappearing, or changing from a proton-accepting property to an acidic property)

[0901] The resist composition may contain, as an acid diffusion control agent, a compound that generates a proton-accepting functional group and decomposes upon irradiation with actinic rays or radiation, thereby reducing or disappearing the proton-accepting property or changing from a proton-accepting property to an acidic property, and does not correspond to the above ionic compound (C) and ionic compound (D) (hereinafter, also referred to as compound (PA).

[0902] The proton-accepting functional group is a functional group having a group or electron capable of electrostatic interaction with a proton. For example, it represents a functional group having a macrocyclic compound structure such as a cyclic polyether, or a functional group having a nitrogen atom as follows, the nitrogen atom having an unshared electron pair that does not contribute to π conjugation. The nitrogen atom having an unshared electron pair that does not contribute to π conjugation is, for example, a nitrogen atom having a partial structure represented by the following general formula.

[0903] [Chemical formula 66]

[0904] Unshared electron pair

[0905] As a preferred partial structure of the proton acceptor functional group, for example, a crown ether structure, an azacrown ether structure, a primary amine structure, a secondary amine structure, a tertiary amine structure, a pyridine structure, an imidazole structure, a pyrazine structure, etc. can be cited.

[0906] Compound (PA) generates a compound that decomposes upon irradiation with actinic rays or radiation, thereby reducing or eliminating the proton acceptor property or changing from a proton acceptor property to an acidic property. Here, the reduction or elimination of the proton acceptor property or the change from the proton acceptor property to the acidic property is a change in the proton acceptor property caused by the addition of a proton to the proton acceptor functional group. Specifically, it means that when a proton adduct is formed from a compound (PA) having a proton acceptor functional group and a proton, the equilibrium constant of the chemical equilibrium decreases.

[0907] As the compound (PA), for example, the compounds described in paragraphs

[0421] to

[0428] of Japanese Unexamined Patent Application Publication No. 2014-41328 and paragraphs

[0108] to

[0116] of Japanese Unexamined Patent Application Publication No. 2014-134686 can be cited, and these contents are incorporated into the present specification.

[0908] A low-molecular compound having a nitrogen atom and a group that detaches by the action of an acid can also be used as an acid diffusion control agent. The above-mentioned low-molecular compound is preferably an amine derivative having a group that detaches by the action of an acid on the nitrogen atom.

[0909] The group that detaches by the action of an acid is preferably an acetal group, a carbonate group, a carbamate group, a tertiary ester group, a tertiary hydroxyl group, or a hemiacetal amine ether group, and more preferably a carbamate group or a hemiacetal amine ether group.

[0910] The molecular weight of the low-molecular compound is preferably 100 to 1000, more preferably 100 to 700, and further preferably 100 to 500.

[0911] The low-molecular compound may also have a carbamate group having a protecting group on the nitrogen atom.

[0912] Specific examples of the acid diffusion control agent (E) are shown below, but the present invention is not limited thereto.

[0913] [Chemical formula 67]

[0914]

[0915] [Chemical formula 68]

[0916]

[0917] [Chemical formula 69]

[0918]

[0919] [Chemical Formula 70]

[0920]

[0921] When the resist composition contains an acid diffusion control agent (E), the content of the acid diffusion control agent (E) is preferably 0.001 to 20.0% by mass, more preferably 0.01 to 5.0% by mass, further preferably not containing the acid diffusion control agent (E), relative to the total solid content of the resist composition.

[0922] The acid diffusion control agent (E) may be used alone or in combination of two or more.

[0923] Examples of the acid diffusion control agent (E) include the compounds (amine compounds, amide group-containing compounds, urea compounds, nitrogen-containing heterocyclic compounds, etc.) described in paragraphs

[0140] to

[0144] of Japanese Patent Laid-Open No. 2013-11833.

[0924] <Hydrophobic resin (F)>

[0925] In addition to the above resin (A), the resist composition may further contain a hydrophobic resin different from the resin (A).

[0926] The hydrophobic resin is preferably designed to be biased towards the surface of the resist film. However, different from a surfactant, it does not necessarily need to have a hydrophilic group in the molecule, and may not contribute to the uniform mixing of polar substances and non-polar substances.

[0927] Examples of the effects brought about by adding the hydrophobic resin include the control of the static and dynamic contact angles of the resist film surface with respect to water and the suppression of outgas.

[0928] From the viewpoint of bias towards the film surface layer, the hydrophobic resin preferably has at least one of "fluorine atom", "silicon atom" and "CH3 partial structure contained in the side chain portion of the resin", more preferably has two or more. And, the above hydrophobic resin preferably has a hydrocarbon group having 5 or more carbon atoms. These groups may be present in the main chain of the resin or may be substituted by side chains.

[0929] When the hydrophobic resin contains a fluorine atom and / or a silicon atom, the above fluorine atom and / or silicon atom in the hydrophobic resin may be contained in the main chain of the resin or may be contained in the side chain.

[0930] When the hydrophobic resin contains a fluorine atom, the partial structure having a fluorine atom is preferably an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom or an aryl group having a fluorine atom.

[0931] The alkyl group having a fluorine atom (preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms) is a linear or branched alkyl group in which at least one hydrogen atom is substituted by a fluorine atom, and may also have substituents other than the fluorine atom.

[0932] The cycloalkyl group having a fluorine atom is a monocyclic or polycyclic cycloalkyl group in which at least one hydrogen atom is substituted by a fluorine atom, and may also have substituents other than the fluorine atom.

[0933] As the aryl group having a fluorine atom, for example, a group in which at least one hydrogen atom in an aryl group such as a phenyl group and a naphthyl group is substituted by a fluorine atom can be cited, and it may also have substituents other than the fluorine atom.

[0934] As the repeating unit having a fluorine atom or a silicon atom, for example, the repeating units exemplified in paragraph

[0519] of US2012 / 0251948A1 can be cited.

[0935] And, as described above, it is also preferable that the hydrophobic resin contains a CH3 partial structure in the side chain portion.

[0936] Here, the CH3 partial structure possessed by the side chain portion in the hydrophobic resin includes the CH3 partial structure possessed by an ethyl group, a propyl group, etc.

[0937] On the other hand, the methyl group directly bonded to the main chain of the hydrophobic resin (for example, the α-methyl of the repeating unit having a methacrylic acid structure) contributes little to the surface segregation of the hydrophobic resin due to the influence of the main chain, and thus is not included in the CH3 partial structure in the present invention.

[0938] Regarding the hydrophobic resin, reference can be made to the descriptions in paragraphs

[0348] to

[0415] of Japanese Patent Laid-Open No. 2014-010245, and these contents are incorporated into the present application specification.

[0939] In addition, in addition to this, resins described in Japanese Patent Laid-Open No. 2011-248019, Japanese Patent Laid-Open No. 2010-175859, and Japanese Patent Laid-Open No. 2012-032544 can also be preferably used as the hydrophobic resin.

[0940] When the resist composition contains a hydrophobic resin, the content of the hydrophobic resin is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, based on the total solid content of the resist composition.

[0941] <Solvent (G)>

[0942] The resist composition may also contain a solvent.

[0943] The solvent preferably contains at least one of (M1) propylene glycol monoalkyl ether carboxylate and (M2), and the (M2) is selected from at least one of the group consisting of propylene glycol monoalkyl ether, lactate, acetate, alkoxypropionate, linear ketone, cyclic ketone, lactone, and alkylene carbonate. In addition, the solvent may further contain components other than the components (M1) and (M2).

[0944] The present inventors have found that when such a solvent is used in combination with the above resin, the coatability of the composition is improved, and a pattern with a small number of development defects can be formed. Although the reason is not clear yet, the present inventors believe that the reason is that since the solubility, boiling point, and viscosity of these solvents in the above resin are well balanced, the unevenness of the film thickness of the composition film and the generation of precipitates during the spin coating process can be suppressed.

[0945] The component (M1) is preferably at least one selected from the group consisting of propylene glycol monomethyl ether acetate (PGMEA: propylene glycol monomethylether acetate), propylene glycol monomethyl ether propionate, and propylene glycol monoethyl ether acetate, and more preferably propylene glycol monomethyl ether acetate (PGMEA).

[0946] The component (M2) is preferably the following solvents.

[0947] The propylene glycol monoalkyl ether is preferably propylene glycol monomethyl ether (PGME) and propylene glycol monoethyl ether (PGEE).

[0948] The lactate is preferably ethyl lactate, butyl lactate, or propyl lactate.

[0949] The acetate is preferably methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, propyl acetate, isoamyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, or 3-methoxybutyl acetate.

[0950] And it is also preferably butyl butyrate.

[0951] The alkoxypropionate is preferably methyl 3-methoxypropionate (MMP) or ethyl 3-ethoxypropionate (EEP).

[0952] The linear ketone is preferably 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonylalcohol, acetylmethanol, acetophenone, methyl naphthyl ketone, or methyl pentyl ketone.

[0953] The cyclic ketone is preferably methylcyclohexanone, isophorone, cyclopentanone, or cyclohexanone.

[0954] The lactone is preferably γ-butyrolactone.

[0955] The alkylene carbonate is preferably propylene carbonate.

[0956] Component (M2) is more preferably propylene glycol monomethyl ether (PGME), ethyl lactate, ethyl 3-ethoxypropionate, methyl pentyl ketone, cyclohexanone, butyl acetate, pentyl acetate, γ-butyrolactone or propylene carbonate.

[0957] In addition to the above components, an ester solvent having 7 or more carbon atoms (preferably 7 to 14, more preferably 7 to 12, and still more preferably 7 to 10) and 2 or less heteroatoms is preferably used.

[0958] Examples of the ester solvent having 7 or more carbon atoms and 2 or less heteroatoms include amyl acetate, 2-methylbutyl acetate, 1-methylbutyl acetate, hexyl acetate, pentyl propionate, hexyl propionate, butyl propionate, isobutyl isobutyrate, heptyl propionate, butyl butyrate, etc., and isopentyl acetate is preferred.

[0959] Component (M2) is preferably a solvent having a flash point (hereinafter also referred to as fp) of 37°C or higher.

[0960] Such component (M2) is preferably propylene glycol monoethyl ether (fp: 47°C), ethyl lactate (fp: 53°C), ethyl 3-ethoxypropionate (fp: 49°C), methyl pentyl ketone (fp: 42°C), cyclohexanone (fp: 44°C), pentyl acetate (fp: 45°C), methyl 2-hydroxyisobutyrate (fp: 45°C), γ-butyrolactone (fp: 101°C) or propylene carbonate (fp: 132°C). Among them, propylene glycol monoethyl ether, ethyl lactate, pentyl acetate or cyclohexanone is more preferred, and propylene glycol monoethyl ether or ethyl lactate is still more preferred.

[0961] In addition, herein, the "flash point" represents the value described in the reagent catalogs of Tokyo Chemical Industry Co., Ltd. or Sigma-Aldrich Corporation.

[0962] The solvent preferably contains component (M1). More preferably, the solvent actually consists only of component (M1) or is a mixed solvent of component (M1) and other components. In the latter case, the solvent further preferably contains both component (M1) and component (M2).

[0963] The mass ratio (M1 / M2) of component (M1) to component (M2) is preferably from "100 / 0" to "0 / 10", more preferably from "100 / 0" to "15 / 85", still more preferably from "100 / 0" to "40 / 60", and particularly preferably from "100 / 0" to "60 / 40".

[0964] That is, when the solvent contains both component (M1) and component (M2), the mass ratio of component (M1) to component (M2) is preferably 15 / 85 or more, more preferably 40 / 60 or more, and still more preferably 60 / 40 or more. By adopting such a constitution, the number of development defects can be further reduced.

[0965] In addition, when the solvent contains both component (M1) and component (M2), the mass ratio of component (M1) to component (M2) is, for example, set to 99 / 1 or less.

[0966] As described above, the solvent may further contain components other than component (M1) and (M2). At this time, the content of the components other than component (M1) and (M2) is preferably 5 to 30% by mass based on the total amount of the solvent.

[0967] The content of the solvent in the resist composition is preferably set so that the solid content concentration is 0.5 to 30% by mass, and more preferably set to 1 to 20% by mass. Thus, the coatability of the resist composition can be further improved.

[0968] In addition, the solid content means all components other than the solvent.

[0969] The solid content concentration is the mass percentage of the mass of the components other than the solvent with respect to the total mass of the resist composition.

[0970] "Total solid content" refers to the total mass of the components obtained by removing the solvent from all the components of the resist composition. And, as described above, the "solid content" refers to the components obtained by removing the solvent, and can be, for example, a solid or a liquid at 25°C.

[0971] <Surfactant (H)>

[0972] The resist composition may also contain a surfactant. When a surfactant is contained, a pattern with more excellent adhesion and fewer development defects can be formed.

[0973] The surfactant is preferably a fluorine-based and / or silicon-based surfactant. Examples of the fluorine-based and / or silicon-based surfactant include the surfactants described in paragraph

[0276] of the specification of U.S. Patent Application Publication No. 2008 / 0248425. Also, Eftop EF301 or EF303 (manufactured by Shin-Akita Kasei Co., Ltd.); Fluorad FC430, 431, and 4430 (manufactured by Sumitomo 3M Limited); Megaface F171, F173, F176, F189, F113, F110, F177, F120, and R08 (manufactured by DIC CORPORATION); Surflon S-382, SC101, 102, 103, 104, 105, or 106 (manufactured by ASAHI GLASS CO., LTD.); TroySol S-366 (manufactured by Troy Chemical Industries Inc.); GF-300 or GF-150 (manufactured by Toagosei Chemical Co., Ltd.), Surflon S-393 (manufactured by SEIMI CHEMICAL CO., LTD.); Eftop EF121, EF122A, EF122B, RF122C, EF125M, EF135M, EF351, EF352, EF801, EF802, or EF601 (manufactured by Gemco Co., Ltd.); PF636, PF656, PF6320, and PF6520 (manufactured by OMNOVA Solutions Inc.); KH-20 (manufactured by Asahi Kasei Corporation); FTX-204G, 208G, 218G, 230G, 204D, 208D, 212D, 218D, and 222D (manufactured by Neos Corporation) can be used. Additionally, as the silicon-based surfactant, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used.

[0974] Furthermore, in addition to the known surfactants as described above, fluorinated aliphatic compounds produced by adjusting the telomerization method (also known as the short-chain polymer (telomer) method) or the oligomerization method (also known as the oligomer method) can be used to synthesize surfactants. Specifically, polymers having fluorinated aliphatic groups derived from the fluorinated aliphatic compounds can be used as surfactants. The fluorinated aliphatic compounds can be synthesized by, for example, the method described in Japanese Patent Application Laid-Open No. 2002-90991.

[0975] Further, surfactants other than those described in paragraph

[0280] of the specification of US Patent Application Publication No. 2008 / 0248425, which are fluorine-based and / or silicon-based, may also be used.

[0976] These surfactants may be used singly or in combination of two or more.

[0977] When the resist composition contains a surfactant, the content of the surfactant is preferably 0.0001 to 2% by mass, more preferably 0.0005 to 1% by mass, based on the total solid content of the composition.

[0978] <Other Additives (I)>

[0979] The resist composition may further contain a dissolution inhibitor, a dye, a plasticizer, a photosensitizer, a light absorber, and / or a compound that promotes solubility in a developer (e.g., a phenolic compound having a molecular weight of 1000 or less or an alicyclic or aliphatic compound containing a carboxyl group).

[0980] The resist composition may further contain a dissolution inhibitor. Here, the "dissolution inhibitor" is a compound having a molecular weight of 3000 or less that decomposes by the action of an acid and has a reduced solubility in an organic developer.

[0981] [Use]

[0982] The composition of the present invention relates to a photosensitive or radiation-sensitive resin composition that reacts upon irradiation with actinic rays or radiation and undergoes a change in properties. More specifically, the composition of the present invention relates to a photosensitive or radiation-sensitive resin composition for use in semiconductor manufacturing processes such as IC (Integrated Circuit) manufacturing, the manufacture of circuit boards for liquid crystals or thermal heads, the production of imprint molds, other photosensitive processing operations, or the manufacture of lithographic printing plates or acid-curable compositions. The pattern formed in the present invention can be used in etching processes, ion implantation processes, bump electrode formation processes, rewiring formation processes, and MEMS (Micro Electro Mechanical Systems), etc.

[0983] [Photosensitive or Radiation-Sensitive Film]

[0984] The present invention also relates to a photosensitive or radiation-sensitive film (also referred to as a "resist film") formed from the photosensitive or radiation-sensitive composition of the present invention. Such a film is formed, for example, by coating the composition of the present invention on a support such as a substrate. The thickness of the film is preferably 0.02 to 0.1 μm.

[0985] As a method of coating on a substrate, it is coated on the substrate by an appropriate coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor blade coating, etc., but spin coating is preferred, and its rotation speed is preferably 1000 to 3000 rpm (rotations per minute). The coating film is pre-baked at 60 to 150 °C for 1 to 20 minutes, preferably pre-baked at 80 to 120 °C for 1 to 10 minutes to form a thin film.

[0986] Examples of the materials constituting the substrate to be processed and its outermost layer include, for example, in the case of a semiconductor wafer, a silicon wafer can be used. Examples of the materials that become the outermost layer include Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, an organic antireflection film, etc.

[0987] [Pattern formation method]

[0988] The steps of the pattern formation method using the above-described resist composition are not particularly limited, and preferably include the following steps.

[0989] Step 1: A step of forming a resist film on a substrate using a resist composition

[0990] Step 2: A step of exposing the resist film (preferably using EUV light)

[0991] Step 3: A step of developing the exposed resist film with a developer to form a pattern

[0992] Hereinafter, the steps of each of the above steps will be described in detail.

[0993] <Step 1: Resist film formation step>

[0994] Step 1 is a step of forming a resist film on a substrate using a resist composition. The definition of the resist composition is as described above.

[0995] As a method of forming a resist film on a substrate using a resist composition, for example, a method of coating the resist composition on the substrate can be cited.

[0996] In addition, it is preferable to filter the resist composition through a filter as needed before coating. The pore size of the filter is preferably 0.1 μm or less, more preferably 0.05 μm or less, and further preferably 0.03 μm or less. And the filter is preferably made of polytetrafluoroethylene, polyethylene, or nylon.

[0997] The resist composition can be applied onto a substrate (e.g., silicon, silicon dioxide-coated) used in the manufacture of integrated circuit elements, etc. by an appropriate coating method such as a spin coater or a coater. The coating method preferably uses spin coating with a spin coater. The rotation speed during spin coating with a spin coater is preferably 1000 to 3000 rpm.

[0998] After applying the resist composition, the substrate can be dried to form a resist film. In addition, various base films (inorganic film, organic film, antireflection film) can be formed under the resist film as needed.

[0999] As a drying method, for example, a method of drying by heating can be cited. Heating can be carried out using the devices provided in a general exposure machine and / or a developing machine, or heating can also be carried out using a hot plate, etc. The heating temperature is preferably 80 to 150 °C, more preferably 80 to 140 °C, and further preferably 80 to 130 °C. The heating time is preferably 30 to 1000 seconds, more preferably 60 to 800 seconds, and further preferably 60 to 600 seconds.

[1000] The film thickness of the resist film is not particularly limited. From the viewpoint of being able to form a finer pattern with higher precision, it is preferably 10 to 65 nm, more preferably 15 to 50 nm.

[1001] In addition, a top coat can be formed on the upper layer of the resist film using a top coat composition.

[1002] Preferably, the top coat composition can be further uniformly applied on the upper layer of the resist film without mixing with the resist film.

[1003] And, it is preferred to dry the resist film before forming the top coat. Then, the top coat composition is applied on the obtained resist film by the same method as the formation method of the above resist film, and further dried, thereby a top coat can be formed.

[1004] The film thickness of the top coat is preferably 10 to 200 nm, more preferably 20 to 100 nm, and further preferably 40 to 80 nm.

[1005] There is no particular limitation on the top coat, and a conventionally known top coat can be formed by a conventionally known method. For example, a top coat can be formed based on the content described in paragraphs

[0072] to

[0082] of Japanese Patent Application Laid-Open No. 2014-059543.

[1006] For example, it is preferred to form a top coat containing a basic compound as described in Japanese Patent Application Laid-Open No. 2013-61648 on the resist film. Specific examples of the basic compound that the top coat can contain can be cited as the basic compounds that the resist composition described later can contain.

[1007] Further, the top coating preferably contains a compound including at least one group or bond selected from the group consisting of an ether bond, a thioether bond, a hydroxyl group, a thiol group, a carbonyl bond, and an ester bond.

[1008] <Process 2: Exposure Process>

[1009] Process 2 is a process of exposing the resist film (preferably with EUV light).

[1010] As a method of exposure, for example, a method of irradiating EUV light on the formed resist film through a prescribed mask can be cited.

[1011] Preferably, baking (heating) is performed before development after exposure. By baking, the reaction in the exposed portion is promoted, and the sensitivity and pattern shape become better.

[1012] The heating temperature is preferably 80 to 150 °C, more preferably 80 to 140 °C, and further preferably 80 to 130 °C.

[1013] The heating time is preferably 10 to 1000 seconds, more preferably 10 to 180 seconds, and further preferably 30 to 120 seconds.

[1014] Heating can be implemented using the devices provided in a general exposure machine and / or developing machine, or a hot plate or the like can also be used for heating.

[1015] This process is also called post-exposure baking.

[1016] <Process 3: Development Process>

[1017] Process 3 is a process of developing the exposed resist film with a developer and forming a pattern.

[1018] The developer can be an alkaline developer or a developer containing an organic solvent (hereinafter, also referred to as an organic developer).

[1019] As a developing method, for example, the following methods can be cited: a method of immersing the substrate in a tank filled with the developer for a certain period of time (dip method); a method of causing the developer to bulge on the substrate surface by surface tension and allowing it to stand for a certain period of time for development (puddle method); a method of spraying the developer onto the substrate surface (spray method); and a method of continuously spraying the developer while scanning a nozzle for spraying the developer at a certain speed on a substrate rotating at a certain speed (dynamic dispense method).

[1020] After the development step, a step of stopping the development while replacing with another solvent can be performed.

[1021] The development time is not particularly limited as long as it is a time sufficient to dissolve the resin in the unexposed portion, preferably 10 to 300 seconds, more preferably 20 to 120 seconds.

[1022] The temperature of the developer is preferably 0 to 50°C, more preferably 15 to 35°C.

[1023] As the alkaline developer, an alkaline aqueous solution containing an alkali is preferably used. The type of the alkaline aqueous solution is not particularly limited, and examples thereof include an alkaline aqueous solution containing a quaternary ammonium salt represented by tetramethylammonium hydroxide, an inorganic base, a primary amine, a secondary amine, a tertiary amine, an alkanolamine, or a cyclic amine. Among them, the alkaline developer is preferably an aqueous solution of a quaternary ammonium salt represented by tetramethylammonium hydroxide (TMAH). In the alkaline developer, an appropriate amount of alcohols, surfactants, etc. can be added. The alkali concentration of the alkaline developer is usually 0.1 to 20% by mass. And the pH of the alkaline developer is usually 10.0 to 15.0.

[1024] The organic developer is preferably a developer containing at least one organic solvent selected from the group consisting of a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent, an ether solvent, and a hydrocarbon solvent.

[1025] Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methyl pentyl ketone), 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonylalcohol, acetylmethanol, acetophenone, methyl naphthyl ketone, isophorone, and propylene carbonate.

[1026] Examples of the ester solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, pentyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butyl butyrate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, and butyl propionate.

[1027] As alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents, for example, the solvents disclosed in paragraphs

[0715] to

[0718] of the specification of US Patent Application Publication No. 2016 / 0070167A1 can be used.

[1028] A plurality of the above solvents can be mixed, or they can be mixed with solvents other than the above or water. As the water content of the entire developing solution, it is preferably less than 50% by mass, more preferably less than 20% by mass, still more preferably less than 10% by mass, and particularly preferably substantially free of water.

[1029] Relative to the total amount of the developing solution, the content of the organic solvent in the organic developing solution is preferably 50% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, still more preferably 90% by mass or more and 100% by mass or less, and particularly preferably 95% by mass or more and 100% by mass or less.

[1030] <Other Processes>

[1031] The above-described pattern forming method preferably includes a step of cleaning with a rinsing liquid after step 3.

[1032] As the rinsing liquid used in the rinsing step after the step of developing with an alkaline developing solution, for example, pure water can be cited. In addition, an appropriate amount of a surfactant can be added to the pure water. An appropriate amount of a surfactant can be added to the rinsing liquid.

[1033] The rinsing liquid used in the rinsing step after the developing step using an organic developing solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used. The rinsing liquid is preferably a rinsing liquid containing at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents.

[1034] Examples of the hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents can be the same solvents as those described in the developing solution containing an organic solvent.

[1035] The method of the rinsing step is not particularly limited. For example, there can be cited a method of continuously spraying the rinsing liquid on a substrate rotating at a constant speed (spin coating method), a method of immersing the substrate in a tank filled with the rinsing liquid for a certain period of time (dipping method), and a method of spraying the rinsing liquid on the substrate surface (spraying method), etc.

[1036] Moreover, the pattern formation method of the present invention may include a post-bake process after the rinsing process. Through this process, the developer and rinsing liquid remaining between and inside the patterns after baking can be removed. Moreover, through this process, there is also an effect of smoothing the resist pattern and improving the surface roughness of the pattern. The post-bake process after the rinsing process is usually carried out at 40 to 250°C (preferably 90 to 200°C) for usually 10 seconds to 3 minutes (preferably 30 seconds to 120 seconds).

[1037] Moreover, the formed pattern can be used as a mask to perform an etching process on the substrate. That is, the pattern formed in Step 3 can also be used as a mask to form a pattern on the substrate by processing the substrate (or the underlying film and the substrate).

[1038] The method for processing the substrate (or the underlying film and the substrate) is not particularly limited. Preferably, a method of forming a pattern on the substrate by using the pattern formed in Step 3 as a mask and performing dry etching on the substrate (or the underlying film and the substrate) is used.

[1039] The dry etching can be single-stage etching or etching composed of multiple stages. When the etching is composed of multiple stages, the etching in each stage can be the same process or different processes.

[1040] Etching can be performed using any known method, and various conditions are appropriately determined according to the type or use of the substrate, etc. For example, etching can also be carried out in accordance with the Proceedings of the International Society for Optical Engineering (Proc. of SPIE) Vol. 6924, 692420 (2008), Japanese Patent Laid-Open No. 2009-267112, etc. Moreover, it can also be carried out in accordance with the method described in "Chapter 4 Etching" of "Semiconductor Process Textbook 4th Edition, published in 2007, publisher: SEMI Japan".

[1041] Among them, the dry etching is preferably oxygen plasma etching.

[1042] In the resist composition and various materials used in the pattern forming method of the present invention (for example, solvents, developers, rinsing liquids, compositions for forming an antireflection film, compositions for forming a top coat, etc.), it is preferred that they do not contain impurities such as metals. The content of impurities contained in these materials is preferably 1 mass ppm or less, more preferably 10 mass ppb or less, further preferably 100 mass ppt or less, particularly preferably 10 mass ppt or less, and most preferably 1 mass ppt or less. Here, as metal impurities, for example, Na, K, Ca, Fe, Cu, Mg, Al, Li, Cr, Ni, Sn, Ag, As, Au, Ba, Cd, Co, Pb, Ti, V, W, and Zn can be mentioned.

[1043] As a method for removing impurities such as metals from various materials, for example, filtration using a filter can be mentioned. The pore diameter of the filter is preferably such that the pore size is less than 100 nm, more preferably 10 nm or less, and further preferably 5 nm or less. The filter is preferably a filter made of polytetrafluoroethylene, polyethylene, or nylon. The filter can be composed of a composite material combining the above filter raw materials and an ion exchange medium. A filter that has been previously cleaned with an organic solvent can be used. In the filter filtration step, multiple filters can be connected in series or in parallel for use. When using multiple filters, filters with different pore diameters and / or materials can be used in combination. Also, various materials can be filtered multiple times, and the step of performing multiple filtrations can be a circulating filtration step.

[1044] In the manufacture of the resist composition, for example, after dissolving various components such as a resin and a photoacid generator in a solvent, it is preferred to perform circulating filtration using multiple filters made of different raw materials. For example, it is preferred to connect a polyethylene filter with a pore diameter of 50 nm, a nylon filter with a pore diameter of 10 nm, and a polyethylene filter with a pore diameter of 3 nm in sequence and perform circulating filtration 10 times or more. The pressure difference between the filters is preferably as small as possible, usually 0.1 MPa or less, preferably 0.05 MPa or less, and more preferably 0.01 MPa or less. The pressure difference between the filter and the filling nozzle is also preferably as small as possible, usually 0.5 MPa or less, preferably 0.2 MPa or less, and more preferably 0.1 MPa or less.

[1045] It is preferred to perform gas replacement of the inside of the manufacturing apparatus for the resist composition with an inert gas such as nitrogen. Thereby, it is possible to suppress the dissolution of active gases such as oxygen in the resist composition.

[1046] After the resist composition is filtered through a filter, it is filled into a clean container. Preferably, the resist composition filled in the container is stored refrigerated. Thereby, deterioration of performance over time is suppressed. The time from the end of filling into the composition container to the start of refrigerated storage is preferably as short as possible, usually within 24 hours, preferably within 16 hours, more preferably within 12 hours, and further preferably within 10 hours. The storage temperature is preferably 0 to 15°C, more preferably 0 to 10°C, and further preferably 0 to 5°C.

[1047] Moreover, as a method for reducing impurities such as metals contained in various materials, for example, a method of selecting a raw material with a low metal content as a raw material constituting various materials, a method of filtering the raw material constituting various materials through a filter, and a method of distilling under conditions of suppressing contamination as much as possible by lining the inside of the apparatus with Teflon (registered trademark), etc. can be cited.

[1048] In addition to filter filtration, impurities can be removed by an adsorbent material, and filter filtration and an adsorbent material can also be used in combination. As the adsorbent material, a known adsorbent material can be used. For example, inorganic adsorbent materials such as silica gel and zeolite, and organic adsorbent materials such as activated carbon can be used. In order to reduce impurities such as metals contained in the above various materials, it is necessary to prevent the mixing of metal impurities in the manufacturing process. It is possible to confirm whether metal impurities have been sufficiently removed from the manufacturing apparatus by measuring the content of metal components contained in the cleaning liquid used when cleaning the manufacturing apparatus. The content of metal components contained in the used cleaning liquid is preferably 100 mass ppt (parts per trillion) or less, more preferably 10 mass ppt or less, and further preferably 1 mass ppt or less.

[1049] In order to prevent failures of the liquid medicine piping and various components (filters, O-rings, hoses, etc.) caused by charging accompanied by static electricity and subsequent electrostatic discharge, a conductive compound can be added to an organic treatment liquid such as a rinsing liquid. The conductive compound is not particularly limited. For example, methanol can be cited. The addition amount is not particularly limited, and from the viewpoint of maintaining preferable development characteristics or rinsing characteristics, it is preferably 10 mass% or less, more preferably 5 mass% or less.

[1050] As the liquid medicine piping, for example, SUS (stainless steel) or various pipes coated with polyethylene, polypropylene, or fluororesin (polytetrafluoroethylene or perfluoroalkoxy resin, etc.) subjected to antistatic treatment can be used. Similarly for the filter and the O-ring, polyethylene, polypropylene, or fluororesin (polytetrafluoroethylene or perfluoroalkoxy resin, etc.) subjected to antistatic treatment can be used.

[1051] For the pattern formed by the method of the present invention, a method for improving the surface roughness of the pattern can also be applied. As a method for improving the surface roughness of the pattern, for example, a method of treating the pattern with plasma of a hydrogen-containing gas disclosed in International Publication No. 2014 / 002808 can be cited. In addition, known methods described in, for example, Japanese Patent Application Laid-Open No. 2004-235468, U.S. Patent Application Publication No. 2010 / 0020297, Japanese Patent Application Laid-Open No. 2008-83384, and Proc. of SPIE Vol. 8328 83280N-1 "EUV Resist Curing Technique for LWR Reduction and Etch Selectivity Enhancement" can also be cited.

[1052] When the formed pattern is linear, the aspect ratio obtained by dividing the pattern height by the line width is preferably 2.5 or less, more preferably 2.1 or less, and still more preferably 1.7 or less.

[1053] When the formed pattern is in the shape of a trench (groove) pattern or a contact hole pattern, the aspect ratio obtained by dividing the pattern height by the trench width or the hole diameter is preferably 4.0 or less, more preferably 3.5 or less, and still more preferably 3.0 or less.

[1054] The pattern formation method of the present invention can also be used for guiding pattern formation in DSA (Directed Self-Assembly) (for example, refer to ACS Nano Vol. 4 No. 8 pages 4815-4823).

[1055] Moreover, the pattern formed by the above method can be used as a core material in a spacer process disclosed in, for example, Japanese Patent Application Laid-Open No. 3-270227 and Japanese Patent Application Laid-Open No. 2013-164509.

[1056] Furthermore, the present invention relates to a method for manufacturing an electronic device including the above pattern formation method and an electronic device manufactured by the manufacturing method.

[1057] The electronic device of the present invention is an electronic device suitably mounted on electrical and electronic devices (home appliances, OA (Office Automation), media-related devices, optical devices, communication devices, etc.).

[1058] Examples

[1059] Hereinafter, the present invention will be further described in detail based on examples. As long as it does not deviate from the gist of the present invention, the materials, usage amounts, ratios, treatment contents, treatment steps, etc. shown in the following examples can be appropriately changed. Therefore, the scope of the present invention should not be construed as being limited by the examples shown below.

[1060] [Various Components of Photosensitive or Radiation-Sensitive Resin Compositions]

[1061] [Resin (A)]

[1062] The following shows Resin A (Resin A-1 to A-19, A'-1 to A'-3) shown in Table 3.

[1063] Resin A-1 to A-19, A'-1 to A'-3 used resins synthesized according to the synthesis method of Resin A-1 (Synthesis Example 1) described later. Table 1 shows the composition ratios (mass% ratios; corresponding from left to right in order) of the respective repeating units described later, the weight-average molecular weight (Mw), and the dispersity (Mw / Mn).

[1064] In addition, the weight-average molecular weight (Mw) and the dispersity (Mw / Mn) of Resin A-1 to A-19, A'-1 to A'-3 were measured by GPC (solvent: tetrahydrofuran (THF)). And the composition ratio (mass% ratio) of the resin was determined by 13 C-NMR (nuclear magnetic resonance).

[1065] In addition, Resin A'-1 to A'-3 are not Resin (A), but for convenience, they are described in Resin (A) in Table 1.

[1066] [Table 1]

[1067] Table 1

[1068]

[1069] The following shows the structural formulas of Resin A-1 to A-19, A'-1 to A'-3 shown in Table 1.

[1070] [Chemical Formula 71]

[1071]

[1072] [Chemical Formula 72]

[1073]

[1074] [Chemical Formula 73]

[1075]

[1076] <Synthesis Example 1: Synthesis of Resin A-1>

[1077] Cyclohexanone (226 g) was heated to 80 °C under a nitrogen stream. While stirring this solution, a mixed solution of the monomer represented by the following formula M-1 (20 g), the monomer represented by the following formula M-2 (50 g), the monomer represented by the following formula M-3 (10 g), the monomer represented by the following formula M-4 (20 g), cyclohexanone (420 g), and dimethyl 2,2'-azobis(2-methylpropionate) [V-601, manufactured by FUJIFILM Wako Pure Chemical Corporation] (12.42 g) was added dropwise over 6 hours to obtain a reaction solution. After the addition was completed, the reaction solution was further stirred at 80 °C for 2 hours. After the obtained reaction solution was naturally cooled, it was reprecipitated with a large amount of methanol / water (mass ratio 9:1) and then filtered, and the obtained solid was dried in vacuo to obtain 83 g of Resin A-1.

[1078] [Chemical Formula 74]

[1079]

[1080] The weight-average molecular weight determined by GPC (solvent: tetrahydrofuran (THF)) of the obtained Resin A-1 was 6500, and the dispersity (Mw / Mn) was 1.52. By 13 The composition ratio determined by C-NMR (nuclear magnetic resonance) was 20 / 50 / 10 / 20 by weight.

[1081] Other resins were synthesized in the same manner.

[1082] [Photoacid Generator]

[1083] <Photoacid Generator (B)>

[1084] The structures of the photoacid generators (B) (Compounds B-1 to B-9) shown in Table 3 are shown below.

[1085] [Chemical Formula 75]

[1086]

[1087] [Photodegradable Quencher]

[1088] <Photodegradable Quencher (C)>

[1089] The structures of the photodegradable quenchers (C) (Compounds C-1 to C-12 and C'-1) shown in Table 3 are shown below.

[1090] In addition, compound C'-1 is not a photodegradable quencher (C), but is described for convenience.

[1091] [Chemical Formula 76]

[1092]

[1093] [Photoacid Generator-Linked Photodegradable Quencher]

[1094] <Photoacid Generator-Linked Photodegradable Quencher (D)><

[1095] The structures of the photoacid generator-linked photodegradable quenchers (D) (compounds D-1 to D-5) shown in Table 3 are shown below.

[1096] [Chemical Formula 77]

[1097]

[1098] [Acid Diffusion Controller]

[1099] The structures of the acid diffusion controllers (E) (compounds E-1 to E-6) shown in Table 3 are shown below.

[1100] [Chemical Formula 78]

[1101]

[1102] [Resin F]

[1103] The resins (F) (resins F-1 to F-6) shown in Table 3 are shown below.

[1104] Resins F-1 to F-6 were synthesized using the synthesis method of resin A-1 (Synthesis Example 1) described above. The composition ratios (mass% ratios; corresponding from left to right in order), weight-average molecular weight (Mw), and dispersity (Mw / Mn) of the respective repeating units described later are shown in Table 2.

[1105] In addition, the weight-average molecular weight (Mw) and dispersity (Mw / Mn) (in terms of polystyrene equivalent) of resins F-1 to F-6 were measured by GPC (solvent carrier: tetrahydrofuran (THF)). And the composition ratio (mass% ratio) of the resin was determined by 13 C-NMR (nuclear magnetic resonance).

[1106] [Table 2]

[1107] Table 2

[1108]

[1109] The structural formulas of Resins F-1 to F-6 shown in Table 2 are shown below.

[1110] [Chemical Formula 79]

[1111]

[1112] [Surfactant]

[1113] The surfactants shown in Table 3 are shown below.

[1114] H-1: Megaface F176 (manufactured by DIC CORPORATION, fluorine-based surfactant)

[1115] H-2: Megaface R08 (manufactured by DIC CORPORATION, fluorine- and silicon-based surfactant)

[1116] H-3: PF656 (manufactured by OMNOVA Solutions Inc., fluorine-based surfactant)

[1117] [Solvent]

[1118] The solvents shown in Table 3 are shown below.

[1119] G-1: Propylene glycol monomethyl ether acetate (PGMEA)

[1120] G-2: Propylene glycol monomethyl ether (PGME)

[1121] G-3: Propylene glycol monoethyl ether (PGEE)

[1122] G-4: Cyclohexanone

[1123] G-5: Cyclopentanone

[1124] G-6: 2-Heptanone

[1125] G-7: Ethyl lactate

[1126] G-8: γ-Butyrolactone

[1127] G-9: Propylene carbonate

[1128] [Preparation of Resist Composition]

[1129] The respective components shown in Table 3 were mixed so that the solid component concentration became 2.0 mass%. Subsequently, the resulting mixed solution was passed through a polyethylene filter with a pore size of 50 nm, then through a nylon filter with a pore size of 10 nm, and finally through a polyethylene filter with a pore size of 5 nm in that order and filtered to prepare resist compositions (Re-1 to Re-30, Re'-1 to Re'-6).

[1130] In addition, the solid components represent all components other than the solvent. The obtained resist compositions were used in the examples and comparative examples.

[1131] Moreover, in the table, the "content" column represents the content (mass %) of each component relative to the total solid components in the resist composition.

[1132] [Table 3]

[1133]

[1134] [Table 4]

[1135]

[1136] [Pattern formation]

[1137] [EUV exposure, organic solvent development]

[1138] A composition AL412 for forming an underlying film (manufactured by Brewer Science) was coated on a 12-inch diameter silicon wafer and baked at 205 °C for 60 seconds to form an underlying film with a thickness of 20 nm. The resist composition shown in Table 2 was coated thereon and baked at 100 °C for 60 seconds to form a resist film with a thickness of 30 nm.

[1139] Using an EUV exposure apparatus (manufactured by Exitech Corporation, Micro Exposure Tool, NA0.3, Quadrupol, outer sigma 0.68, inner sigma 0.36), the silicon wafer with the obtained resist film was pattern-irradiated so that the average line width of the obtained pattern became 20 nm. In addition, as a reticle, a mask with a line size = 20 nm and a line:space = 1:1 was used.

[1140] After baking the exposed resist film at 90 °C for 60 seconds, it was developed with n-butyl acetate for 30 seconds and spin-dried to obtain a negative pattern.

[1141] [Evaluation]

[1142] <Line width roughness before aging (LWR performance before aging, nm)>

[1143] The pattern obtained by the above method was observed from above the pattern using a length-measuring scanning electron microscope (SEM (Hitachi, Ltd. S-9380II)). The line width of the pattern was observed at 250 points, and the measurement deviation was evaluated by 3σ and designated as LWR (nm). The smaller the value of LWR, the better the LWR performance before aging.

[1144] In addition, in the evaluation of the LWR performance before aging, a pattern was formed using the resist composition just after preparation for evaluation.

[1145] Moreover, the LWR (nm) before aging is preferably in the order of 5.0 nm or less, 4.7 nm or less, 4.4 nm or less, 4.1 nm or less, 3.8 nm or less, 3.5 nm, 3.2 nm or less.

[1146] <Line width roughness after aging (LWR performance after aging, nm)>

[1147] The pattern obtained by the above method was observed from above the pattern using a length-measuring scanning electron microscope (SEM (Hitachi, Ltd. S-9380II)). The line width of the pattern was observed at 250 positions, and the measurement deviation was evaluated by 3σ and defined as LWR (nm). The smaller the value of LWR, the better the LWR performance after aging.

[1148] In addition, in the evaluation of the LWR performance after aging, a pattern was formed using the resist composition stored in a dark room at room temperature (25 °C) for 180 days after preparation for evaluation.

[1149] Moreover, the LWR (nm) after aging is preferably in the order of 5.0 nm or less, 4.7 nm or less, 4.4 nm or less, 4.1 nm or less, 3.8 nm or less, 3.5 nm, 3.2 nm or less.

[1150] <Defect evaluation before retention (defect suppression)>

[1151] Using UVision5 (manufactured by AMAT) and SEMVisionG4 (manufactured by AMAT), the number of defects per silicon wafer was calculated, and the pattern obtained by the above method was evaluated according to the following evaluation criteria. The fewer the number of defects, the better the defect suppression.

[1152] In addition, in the evaluation of defect suppression, a resist film was formed using the resist composition just after preparation, and EUV exposure was immediately performed after coating and baking to form a pattern.

[1153] "A": The number of defects is 50 or less

[1154] "B": The number of defects exceeds 50 and is 100 or less

[1155] "C": The number of defects exceeds 100 and is 200 or less

[1156] "D": The number of defects exceeds 200 and is 300 or less

[1157] "E": The number of defects exceeds 300 and is 400 or less

[1158] "F": The number of defects exceeds 400 and is less than 500

[1159] "G": The number of defects exceeds 500 and is less than 600

[1160] "H": The number of defects exceeds 600 and is less than 700

[1161] "I": The number of defects exceeds 700 and is less than 800

[1162] "J": The number of defects exceeds 800 and is less than 900

[1163] "K": The number of defects exceeds 900 and is less than 1000

[1164] "L": The number of defects exceeds 1000 and is less than 1100

[1165] "M": The number of defects exceeds 1100 and is less than 1200

[1166] "N": The number of defects exceeds 1200 and is less than 1300

[1167] "O": The number of defects exceeds 1300 and is less than 1400

[1168] <Post - placement defect evaluation (defect suppression ability)>

[1169] Using UVision5 (manufactured by AMAT) and SEMVisionG4 (manufactured by AMAT), the number of defects per silicon wafer was calculated, and the patterns obtained by the above - mentioned method were evaluated according to the following evaluation criteria. The fewer the number of defects, the better the defect suppression ability.

[1170] In addition, in the evaluation of defect suppression ability, a resist film was formed using the freshly prepared resist composition, and the coated and baked resist film was stored in a dark room at room temperature (25 °C) for 48 hours and then subjected to EUV exposure to form a pattern.

[1171] The above "A" to "O" were used as evaluation indicators.

[1172] The evaluation results are shown in Table 4 below.

[1173] [Table 5]

[1174]

[1175] As shown in Table 4 above, it was confirmed that the resist composition of the present invention has excellent LWR performance over time and defect performance (defect suppression) after retention when forming a pattern by development with an organic solvent. On the other hand, in the resist compositions of the comparative examples, these performances were insufficient.

[1176] 〔EUV Exposure, Alkaline Aqueous Solution Development〕

[1177] A composition AL412 for forming an underlayer film (manufactured by Brewer Science) was coated on a 12-inch silicon wafer and baked at 205°C for 60 seconds to form a base film with a film thickness of 20 nm. The resist composition shown in Table 4 was coated thereon and baked at 100°C for 60 seconds to form a resist film with a film thickness of 30 nm.

[1178] Using an EUV exposure apparatus (manufactured by Exitech Corporation, Micro Exposure Tool, NA 0.3, Quadrupol, outer sigma 0.68, inner sigma 0.36), the silicon wafer having the obtained resist film was irradiated with a pattern so that the average line width of the obtained pattern became 20 nm. In addition, as a mask, a mask with a line size = 20 nm and a line:space = 1:1 was used.

[1179] After baking the exposed resist film at 90°C for 60 seconds, it was developed with a tetramethylammonium hydroxide aqueous solution (2.38% by mass) for 30 seconds, and then rinsed with pure water for 30 seconds. Thereafter, it was spin-dried to obtain a positive pattern.

[1180] Using the obtained positive pattern, the LWR performance before and after aging and the defect suppression before and after retention were evaluated in the same manner as above.

[1181] The evaluation results are shown in Table 5 below.

[1182] [Table 6]

[1183]

[1184] As shown in Table 5 above, it was confirmed that the resist composition of the present invention also has excellent LWR performance over time and defect performance (defect suppression) after retention when forming a pattern by alkaline development. On the other hand, in the resist compositions of the comparative examples, these performances were insufficient.

[1185] Industrial Applicability

[1186] According to the present invention, it is possible to provide a photosensitized or radiation-sensitive resin composition that can obtain a pattern with excellent LWR performance even after long-term storage in a pattern formed using EUV light, and can suppress the generation of pattern defects even when a standing time occurs after coating.

[1187] Moreover, according to the present invention, it is possible to provide a photosensitized or radiation-sensitive film, a pattern forming method, and a method for manufacturing an electronic device using the above-mentioned photosensitized or radiation-sensitive resin composition.

[1188] The present invention has been described in detail with reference to specific embodiments, but it is obvious to those skilled in the art that various changes or modifications can be added without departing from the spirit and scope of the present invention.

[1189] This application is based on a Japanese patent application filed on December 27, 2019 (Japanese Patent Application 2019-239614), the content of which is incorporated herein by reference.

Claims

1. A photosensitive or radiation-sensitive resin composition, comprising: (A) A resin containing a repeating unit (a1) having a structure represented by the following general formula (1); (B) A compound that generates an acid upon irradiation with actinic rays or radiation; and (C) An ionic compound that is a compound whose acid-trapping property is reduced by decomposition upon irradiation with actinic rays or radiation, has an anionic acid-trapping group, does not have a non-ionic acid-trapping group, and contains a fluorine atom in the anion part, The resin (A) further contains a repeating unit (a2) having an acid group, In general formula (1), n a1 represents an integer of 1 or more, R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom or a hydroxyl group, and when n a1 represents an integer of 2 or more, a plurality of Rs 1 and R 2 are the same or different, respectively * represents a bonding position.

2. The photosensitive or radiation-sensitive resin composition according to claim 1, wherein The repeating unit (a1) is a repeating unit (a1-2) represented by the following general formula (1-2), In general formula (1-2), X a1 represents a hydrogen atom, an alkyl group or a halogen atom, A a1 represents a single bond, a divalent chain hydrocarbon group, -O-, -C(=O)-, or a divalent linking group formed by combining these n a1 represents an integer of 1 or more, R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group, a halogen atom or a hydroxyl group, and when n a1 represents an integer of 2 or more, a plurality of Rs 1 and R 2 are the same or different, respectively.

3. The photosensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein The ionic compound (C) is a compound that generates an acid weaker than the acid generated from the compound (B) that generates an acid upon irradiation with actinic rays or radiation, The difference in pKa between the acid generated from the ionic compound (C) and the acid generated from the compound (B) that generates an acid upon irradiation with actinic rays or radiation is 1.00 or more.

4. The photosensitive or radiation-sensitive resin composition according to claim 3, wherein The acid group in the repeating unit (a2) is a phenolic hydroxyl group or a fluorinated alkyl alcohol group.

5. The photosensitive or radiation-sensitive resin composition according to any one of claims 1, 2, and 4, wherein The ionic compound (C) is a compound represented by any one of the following general formulas (C1) to (C3), In general formula (C1), R C1 represents a cycloalkyl or aryl group, L C1 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these wherein at least one of R C1 and L C1 is substituted with a fluorine atom or a group having a fluorine atom M C + represents an organic cation, In general formula (C2), R C2 represents a cycloalkyl or aryl group, L C2 represents a single bond, an alkylene group, a cycloalkylene group, -O-, -C(=O)-, or a divalent linking group formed by combining these wherein at least one of R C2 and L C2 is substituted by a fluorine atom or a group having a fluorine atom M C + represents an organic cation, In general formula (C3), A C31 and A C32 each independently represents -SO2-R PC1 or -CO-R PC2 , R PC1 and R PC2 represent organic groups, Among them, A C31 and A C32 are at least one of which is substituted by a fluorine atom or a group having a fluorine atom M C + represents an organic cation.

6. The photosensitive or radiation-sensitive resin composition according to claim 5, wherein M in the general formulas (C1) to (C3) C + is a cation represented by the following general formula (ZcI) or general formula (ZcII), In general formula (ZcI), R C01 , R C02 and R C03 Each independently represents an organic group, In general formula (ZcII), R C04 and R C05 each independently represents aryl, alkyl or cycloalkyl.

7. The photosensitive or radiation-sensitive resin composition according to any one of claims 1, 2, and 4, wherein The compound (B) that generates an acid upon irradiation with actinic rays or radiation and the ionic compound (C) are the same compound, i.e., an ionic compound (D). The ionic compound (D) generates an acid upon irradiation with actinic rays or radiation and has its acid-trapping property reduced by decomposition upon irradiation with actinic rays or radiation. The ionic compound (D) has an anionic acid-trapping group, does not have a non-ionic acid-trapping group, and contains a fluorine atom in the anion part.

8. The photosensitive or radiation-sensitive resin composition according to claim 7, wherein The ionic compound (D) is a compound represented by the following general formula (PD), In general formula (PD), M D1 + and M D2 + each independently represents an organic cation, L D represents a divalent organic group, A D1 - and B D1 - each independently represents an acid anion group, L D 、A D1 - and B D1 - is substituted by at least any one of a fluorine atom or a group having a fluorine atom. Among them, in the compound M represented by the general formula (PD), D1 + and M D2 + where HA in which M and M are each replaced by a hydrogen atom D1 -L D -B D1 In the compound represented by H, the pKa of the group represented by HA D1 is lower than the pKa of the group represented by B D1 H.

9. The photosensitive or radiation-sensitive resin composition according to claim 7, wherein In addition to the ionic compound (D), it further contains at least one of the compound (B) that generates an acid upon irradiation with actinic rays or radiation and the ionic compound (C).

10. The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1, 2, 4, 6, 8, and 9, wherein the ionic compound (C) has a fluorine atom in the cationic moiety.

11. The actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1, 2, 4, 6, 8, and 9, wherein the compound (B) that generates an acid upon irradiation with actinic rays or radiation has a fluorine atom in the cationic moiety.

12. An actinic ray-sensitive or radiation-sensitive film, which is formed using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 11.

13. A pattern forming method, comprising: a step of forming a resist film on a substrate using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 11; a step of exposing the resist film; and a step of developing the exposed resist film with a developer to form a pattern.

14. A method for manufacturing an electronic device, which includes the pattern forming method according to claim 13.

Images