NOVEL PHOTOACID GENERATOR, PHOTORESIST COMPOSITION, AND METHOD FOR FORMING PHOTORESIST PATTERN

Abstract

The present invention relates to a photoacid generator having a novel structure containing an anion having a specific polar functional group such as a sulfonate group, a photoresist composition containing the same, and a method for forming a photoresist pattern.

Description

[Technical field]

[0001] The present invention relates to a novel photoacid generator, a photoresist composition containing the same, and a method for forming a photoresist pattern using the same. [Background technology]

[0002] Lithography is a technology that forms a pattern by applying a resist material made of photosensitive material onto a substrate to form a resist film, and then transferring the mask pattern onto the resist film through exposure and development using a light source selected from near ultraviolet (NUV), deep ultraviolet (DUV), electron beam (e-beam), and extreme ultraviolet (EUV) using a mask on which a pattern has been formed. Resists are classified into positive type, in which the exposed area dissolves in the developer due to a change in characteristics, and negative type, in which the exposed area does not dissolve in the developer.

[0003] As the miniaturization of semiconductor patterns requires the use of light sources with shorter wavelengths, near ultraviolet (g-line_436nm, i-line_365nm) has been used, and currently, deep ultraviolet (KrF_248nm, ArF_193nm) excimer lasers are used, and ArF-immersion and multi-patterning methods using this are widely used in the mass production of semiconductor devices.

[0004] With the demand for higher element integration in semiconductor devices manufactured using lithography technology increasing year by year, competition to gain an advantage by securing leading technology is intensifying. The most effective way to increase the number of chips integrated per unit area of ​​silicon wafers used in manufacturing semiconductor chips is to minimize the circuit line width (CD, critical dimension). In order to minimize the line width, it is necessary to apply lithography technology with higher resolution, and as mentioned above, using a light source with a short wavelength is the most reliable way to increase the resolution of lithography technology. Currently, ArF light source (193 nm) is mainly used, and recently lithography technology using extreme ultraviolet (EUV, 13.5 nm) wavelength has begun to be applied to mass production processes.

[0005] Meanwhile, resist materials are required to have characteristics such as sensitivity to an exposure light source and resolution capable of reproducing fine mask patterns. Resist components that can exhibit such characteristics include photoacid generators that generate acid during the exposure process, polymer resins whose solubility in an alkaline developer changes due to the action of the generated acid, and acid diffusion controllers (quenchers) that can adjust the diffusion distance of the acid. By adding a solvent that can dissolve each component, a chemically amplified photoresist (CAR) resist composition can be manufactured.

[0006] The base resin of the KrF resist composition is mainly polyhydroxystyrene-based (poly-hydroxystyrene_PHS), an acrylic resin having an acrylic ester unit, or a mixture of these. The base resin of the ArF resist composition is generally a methacrylic resin having a methacrylic ester unit, which has excellent transparency under an ArF light source. The base resin of the EUV resist composition may be any monomer used for the base resin for the KrF and ArF resists, depending on the characteristics of the light source having a short wavelength, or may be a wide variety of polymer or copolymer base resins, depending on the characteristics.

[0007] A variety of structures have been proposed for photoacid generators used in chemically amplified resist compositions, including onium salts such as sulfonium salts and iodonium salts, diazomethane, oxine, nitrobenzylsulfonate, iminosulfonate, and disulfone acid generators, which may be used alone or in combination of two or more. In addition to a base resin and an acid generator, chemically amplified resist compositions use nitrogen-containing organic substances such as amines and amides, or further use a photosensitive quencher, in an attempt to improve resist performance by regulating the diffusion of the acid generated from the photoacid generator.

[0008] However, in developing high resolution resists, in order to overcome the line width roughness (LER / LWR), it is essential to fundamentally control the diffusion length of the acid. Also, in order to improve the diffusion speed and length of the acid in the resist composition, the structure of the anion moiety has the greatest effect on the strength of the acid, the diffusion speed and distance. However, when using existing resist materials, the line width roughness required to form a desired pattern size is still not satisfied.

[0009] Therefore, there remains a need for the development of a resist material having a new structure capable of controlling the diffusion rate and length of an acid, which can ensure high contrast and improve process margins when forming fine patterns. Summary of the Invention [Problem to be solved by the invention]

[0010] Therefore, the present invention provides a novel photoacid generator that can provide a photoresist composition having a wide process margin by ensuring high contrast and improving limiting resolution due to a short diffusion length of anion acid generated upon exposure due to improved polarity, and by simultaneously satisfying improvement of CDU (Critical Dimension Uniformity), low sensitivity and LER / LWR value. The present invention also provides a photoresist composition containing the photoacid generator. The present invention also provides a method for forming a photoresist pattern using the photoresist composition. [Means for solving the problem]

[0011] The present specification provides a photoacid generator comprising an anion represented by the following Chemical Formula 1 and a cation represented by the following Chemical Formula 2: [Chemical formula 1]

[0012] JPEG2025500245000002.jpg9160 [Chemical formula 2]

[0013] JPEG2025500245000003.jpg12160

[0014] In the above formulas 1 and 2, A and Z are the same or different and each independently represents a polar functional group; Y is a linker connecting A and Z and is a divalent organic group; R represents a linear or cyclic aliphatic hydrocarbon group or a monocyclic or polycyclic aromatic hydrocarbon group; EWG is an electron withdrawing group substituted on R; M + is an onium ion or a metal ion.

[0015] In addition, in this specification, The photoacid generator; A base polymer; An acid diffusion inhibitor; and an organic solvent.

[0016] The present invention further comprises the steps of applying and heating the photoresist composition to form a photoresist film; exposing the photoresist film to light; and developing the exposed photoresist film to form a photoresist pattern.

[0017] The present invention will be described in more detail below. The terms and words used in the present specification and claims should not be interpreted in a limited manner based on their ordinary or dictionary meanings, but should be interpreted in a manner that is consistent with the technical concept of the present invention, based on the principle that the inventor can appropriately define the concept of the term in order to best describe his / her invention.

[0018] Additionally, the meaning of "comprising" as used in the present specification does not refer to the specification of certain properties, regions, integers, steps, operations, elements and / or components and does not refer to the exclusion of the presence or inclusion of other properties, regions, integers, steps, operations, elements and / or components.

[0019] In this specification, the weight average molecular weight is a polystyrene equivalent weight average molecular weight measured using GPC, and the weight average molecular weight was measured using the standard analytical method of a gel permeation chromatography (GPC) system used in a Waters e2695 Alliance Separation Module. In this specification, the term polymer may be used interchangeably with the terms macromolecule and polymeric substance. In this specification, examples of the substituents are described below, but are not limited thereto.

[0020] In this specification, the term "substituted" means that another atom or functional group is bonded in place of a hydrogen atom or a carbon atom in a compound, and the position of the substitution is not limited as long as it is a position where a hydrogen atom or a carbon atom is substituted, that is, a position where a substituent can be substituted, and when two or more substitutions are performed, the two or more substituents may be the same or different from each other.

[0021] In the present specification, the term "substituted or unsubstituted" means that the group is substituted or unsubstituted with one or more substituents selected from the group consisting of halogen, cyano group, nitro group, hydroxy group, carbonyl group, ester group, imide group, amide group, amino group, carboxy group, sulfonic acid group, sulfonamide group, phosphine oxide group, alkoxy group, alkylcarbonyl group, alkoxycarbonyl group, sulfonyl group, aryloxy group, alkylthiooxy group, arylthiooxy group, alkylsulfoxy group, arylsulfoxy group, silyl group, and boron group, or that the group is substituted or unsubstituted with a substituent in which two or more of the above-mentioned examples of the substituents are linked. For example, the "substituent in which two or more substituents are linked" may be a biphenyl group. In other words, the biphenyl group may be an aryl group, and may be interpreted as a substituent in which two phenyl groups are linked.

[0022] As used herein,

[0023] JPEG2025500245000004.jpg19160 or

[0024] JPEG2025500245000005.jpg5160 denotes a bond that is connected to another substituent.

[0025] In this specification, examples of halogen include fluorine, chlorine, bromine or iodine. In the present specification, the number of carbon atoms of the imido group is not particularly limited, and may be 1 to 30. Specifically, the imido group may have a compound having the following structure, but is not limited thereto.

[0026] JPEG2025500245000006.jpg69160

[0027] In the present specification, the nitrogen of the amide group may be substituted with hydrogen, a linear, branched, or cyclic alkyl group having 1 to 30 carbon atoms, or an aryl group having 6 to 30 carbon atoms. Specifically, the amide group may be a compound having the following structural formula, but is not limited thereto.

[0028] JPEG2025500245000007.jpg47160

[0029] In the present specification, the number of carbon atoms of the carbonyl group is not particularly limited, but may be 1 to 30. Specifically, the carbonyl group may have a compound having the following structure, but is not limited thereto.

[0030] JPEG2025500245000008.jpg62159

[0031] In the present specification, the oxygen of the ester group may be substituted with a linear, branched, or cyclic alkyl group having 1 to 25 carbon atoms or an aryl group having 6 to 25 carbon atoms. Specifically, the ester group may be a compound having the following structural formula, but is not limited thereto.

[0032] JPEG2025500245000009.jpg88159

[0033] As used herein, the sulfonamide group may be -SONR'R", wherein R' and R" are the same or different and may each be independently selected from the group consisting of hydrogen; deuterium; halogen; a nitrile group; a substituted or unsubstituted monocyclic or polycyclic cycloalkyl group having 3 to 30 carbon atoms; a substituted or unsubstituted linear or branched alkyl group having 1 to 30 carbon atoms; a substituted or unsubstituted monocyclic or polycyclic aryl group having 6 to 30 carbon atoms; and a substituted or unsubstituted monocyclic or polycyclic heteroaryl group having 2 to 30 carbon atoms.

[0034] In this specification, the alkyl group may be linear or branched, and the number of carbon atoms of the linear alkyl group is not particularly limited, but may be 1 to 20. In addition, the number of carbon atoms of the branched alkyl group is 3 to 20. Specific examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl, and the like. The alkyl group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0035] In the present specification, the cycloalkyl group is not particularly limited, but may have 3 to 60 carbon atoms, and in one embodiment, the cycloalkyl group has 3 to 30 carbon atoms. In another embodiment, the cycloalkyl group has 3 to 20 carbon atoms. In another embodiment, the cycloalkyl group has 3 to 6 carbon atoms. Specific examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, and cyclooctyl. The cycloalkyl group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0036] In the present specification, the alkoxy group is a functional group in which the above-mentioned alkyl group is bonded to one end of an ether group (-O-), and the above-mentioned description of the alkyl group can be applied except that the alkoxy group is a functional group bonded to an ether group (-O-). For example, the alkoxy group may be linear, branched, or cyclic. The number of carbon atoms of the alkoxy group is not particularly limited, and may be 1 to 20 carbon atoms. Specific examples include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, i-propyloxy, n-butoxy, isobutoxy, tert-butoxy, sec-butoxy, n-pentyloxy, neopentyloxy, isopentyloxy, n-hexyloxy, 3,3-dimethylbutyloxy, 2-ethylbutyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, cycloheptoxy, benzyloxy, and p-methylbenzyloxy. The alkoxy group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0037] In the present specification, the amine group may be selected from the group consisting of -NH, a monoalkylamine group, a dialkylamine group, an N-alkylarylamine group, a monoarylamine group, a diarylamine group, an N-arylheteroarylamine group, an N-alkylheteroarylamine group, a monoheteroarylamine group, and a diheteroarylamine group, and the number of carbon atoms is not particularly limited and may be 1 to 30. Specific examples of the amine group include, but are not limited to, methylamine group, dimethylamine group, ethylamine group, diethylamine group, phenylamine group, naphthylamine group, biphenylamine group, anthracenylamine group, 9-methyl-anthracenylamine group, diphenylamine group, ditolylamine group, N-phenylbiphenylamine group, N-phenylnaphthylamine group, N-biphenylnaphthylamine group, ditolylamine group, N-phenyltolylamine group, triphenylamine group, N-naphthylfluorenylamine group, N-phenylphenanthrenylamine group, N-biphenylphenanthrenylamine group, N-phenylfluorenylamine group, N-phenylterphenylamine group, N-phenanthrenylfluorenylamine group, and N-biphenylfluorenylamine group. The amine group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0038] As used herein, an N-alkylarylamine group refers to an amine group in which the N of the amine group is substituted with an alkyl group and an aryl group. As used herein, an N-arylheteroarylamine group refers to an amine group in which the N of the amine group is substituted with an aryl group and a heteroaryl group. As used herein, an N-alkylheteroarylamine group refers to an amine group in which the N of the amine group is substituted with an alkyl group and a heteroarylamine group.

[0039] In this specification, the alkyl groups in the monoalkylamine group, dialkylamine group, N-arylalkylamine group, alkylthioxy group, alkylsulfoxy group, and N-alkylheteroarylamine group are the same as the alkyl groups exemplified above. Specifically, the alkylthioxy group includes a methylthioxy group, an ethylthioxy group, a tert-butylthioxy group, a hexylthioxy group, and an octylthioxy group, and the alkylsulfoxy group includes, but is not limited to, a mesyl group, an ethylsulfoxy group, a propylsulfoxy group, and a butylsulfoxy group.

[0040] In the present specification, the alkenyl group may be linear or branched, and the number of carbon atoms is not particularly limited, and may be 2 to 40. The above description of the alkyl group may be applied to the alkenyl group, except that the alkenyl group contains at least one unsaturated bond (double bond or triple bond) in the functional group. According to one embodiment, the number of carbon atoms in the alkenyl group is 2 to 20. According to another embodiment, the number of carbon atoms in the alkenyl group is 2 to 10. According to another embodiment, the number of carbon atoms in the alkenyl group is 2 to 6. Specific examples include, but are not limited to, vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1-butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2-(naphthyl-1-yl)vinyl-1-yl, 2,2-bis(diphenyl-1-yl)vinyl-1-yl, stilbenyl group, styrenyl group, etc. The alkenyl group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0041] In the present specification, the cycloalkenyl group may have 3 to 60 carbon atoms, and in one embodiment, the cycloalkenyl group has 3 to 30 carbon atoms. In another embodiment, the cycloalkenyl group has 3 to 20 carbon atoms. In another embodiment, the cycloalkenyl group has 3 to 6 carbon atoms. The above description of the cycloalkyl group can be applied to the cycloalkenyl group, except that the cycloalkenyl group contains at least one unsaturated bond (double bond or triple bond) in the functional group. The cycloalkenyl group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0042] In the present specification, specific examples of the silyl group include, but are not limited to, a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, a phenylsilyl group, etc. The silyl group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.

[0043] In the present specification, specific examples of the boron group include, but are not limited to, a trimethyl boron group, a triethyl boron group, a t-butyl dimethyl boron group, a triphenyl boron group, a phenyl boron group, etc. The boron group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0044] In the present specification, the aryl group is not particularly limited, and may have 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to one embodiment, the aryl group has 6 to 30 carbon atoms. According to one embodiment, the aryl group has 6 to 20 carbon atoms. The aryl group may be a monocyclic aryl group, such as a phenyl group, a biphenyl group, a terphenyl group, etc., but is not limited thereto. The polycyclic aryl group may be a naphthyl group, an anthracenyl group, etc., but is not limited thereto. The aryl group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.

[0045] In this specification, the aryl group among the monoarylamine group, diarylamine group, aryloxy group, arylthioxy group, arylsulfoxy group, N-arylalkylamine group, N-arylheteroarylamine group and arylphosphine group is the same as the above-mentioned examples of the aryl group. Specifically, aryloxy groups include phenoxy groups, p-tolyloxy groups, m-tolyloxy groups, 3,5-dimethyl-phenoxy groups, 2,4,6-trimethylphenoxy groups, p-tert-butylphenoxy groups, 3-biphenyloxy groups, 4-biphenyloxy groups, 1-naphthyloxy groups, 2-naphthyloxy groups, 4-methyl-1-naphthyloxy groups, 5-methyl-2-naphthyloxy groups, 1-anthryloxy groups, 2-anthryloxy groups, 9-anthryloxy groups, 1-phenanthryloxy groups, 3-phenanthryloxy groups, and 9-phenanthryloxy groups; arylthioxy groups include phenylthioxy groups, 2-methylphenylthioxy groups, and 4-tert-butylphenylthioxy groups; and arylsulfoxy groups include, but are not limited to, benzenesulfoxy groups and p-toluenesulfoxy groups.

[0046] In this specification, the heterocyclic group is a heterocyclic group containing one or more of O, N, Se and S as a hetero element, and the number of carbon atoms is not particularly limited, and may be 2 to 60 carbon atoms.

[0047] Examples of heterocyclic groups include, but are not limited to, thiophene, furan, pyrrole, imidazole, thiazole, oxazole, oxadiazole, triazole, pyridyl, bipyridyl, pyrimidyl, triazine, acridyl, pyridazine, pyrazinyl, quinolinyl, quinazoline, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinoline, indole, carbazole, benzoxazole, benzimidazole, benzothiazole, benzocarbazole, benzothiophene, dibenzothiophene, benzofuranyl, phenanthroline, thiazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, benzothiazolyl, phenothiazinyl, and dibenzofuranyl groups.

[0048] In the present specification, a heteroaryl group includes one or more non-carbon atoms, heteroatoms, and specifically, the heteroatoms may include one or more atoms selected from the group consisting of O, N, Se, S, etc. The number of carbon atoms is not particularly limited, and may be 2 to 60, and the heteroaryl group may be monocyclic or polycyclic. Examples of the heteroaryl group include a thiophene group, a furanyl group, a pyrrole group, an imidazolyl group, a thiazolyl group, an oxazolyl group, an oxadiazolyl group, a pyridyl group, a bipyridyl group, a pyrimidyl group, a triazinyl group, a triazolyl group, an acridyl group, a pyridazinyl group, a pyrazinyl group, a quinolinyl group, a quinazolyl group, a quinoxalinyl group, a phthalazinyl group, a pyridopyrimidyl group, a pyridopyrazinyl group, a pyrazinopyrazinyl group, an isoquinolinyl group, an indolyl group, a carbazolyl group, a benzoxazolyl group, a benzimidazolyl group, a benzothiazolyl group, a benzocarbazolyl group, a benzothiophene group, a dibenzothiophene group, Examples of heteroaryl groups include, but are not limited to, benzofuranyl, phenanthrolinyl, thiazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, benzothiazolyl, phenothiazinyl, aziridyl, azaindolyl, isoindolyl, indazolyl, purine, pteridine, beta-carbonyl, naphthyridyl, ter-pyridyl, phenazinyl, imidazopyridyl, pyropyridyl, azepine, pyrazolyl, and dibenzofuranyl. The heteroaryl group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0049] In this specification, examples of the heteroaryl group among the monoheteroarylamine group, diheteroarylamine group, N-arylheteroarylamine group, and N-alkylheteroarylamine group may be selected from the examples of the heteroaryl group described above.

[0050] Hereinafter, a novel photoacid generator according to an embodiment of the present invention, a photoresist composition containing the same, and a method for forming a photoresist pattern using the photoresist composition will be described in more detail.

[0051] New photoacid generator According to an embodiment of the present invention, there is provided a photoacid generator including an anion represented by the following Chemical Formula 1 and a cation represented by the following Chemical Formula 2: [Chemical formula 1]

[0052] JPEG2025500245000010.jpg8159 [Chemical formula 2]

[0053] JPEG2025500245000011.jpg12159 In the above formulas 1 and 2, A and Z are the same or different and each independently represents a polar functional group; Y is a linker connecting A and Z and is a divalent organic group; R represents a linear or cyclic aliphatic hydrocarbon group or a monocyclic or polycyclic aromatic hydrocarbon group; EWG is an electron withdrawing group substituted on R; M + is an onium ion or a metal ion.

[0054] The present inventors have confirmed through experiments that when a photoacid generator has a substituted structure containing a polar group such as a sulfonyloxy group (-SO3-) or a carbonyloxy group (-(C=O)O-) in the anion structure represented by Chemical Formula 1, it is possible to impart more polarity than before, and the diffusion length of the anion acid generated upon exposure is shortened, thereby ensuring high contrast and improving the limiting resolution, and improving the low sensitivity and LER value, thereby obtaining a wide process margin, thereby completing the invention.

[0055] In particular, when the anion of Formula 1 contains an aromatic sulfonyloxy group substituted with an electron-withdrawing group (EWG), it is possible to obtain a resist composition having improved exposure sensitivity and high contrast between exposed and unexposed areas, improved resolution, and low line width roughness, thereby improving process margins, compared to a case where the anion does not contain an aromatic sulfonyloxy group.

[0056] Therefore, the present invention can provide a novel photoacid generator which contains a specific anion moiety structure, has improved acid strength, and anion diffusion rate and diffusion length compared to conventional ones, and is used in the production of high-resolution resists.

[0057] According to one embodiment of the photoacid generator, the anion of the formula 1 is a sulfonate group (-SO3 - ) or carbonate group (-CO3 2- ) in the above formula 1. Specifically, A in the above formula 1 may be a sulfonate group (-SO3 - In this case, the sulfonate group has a higher polarity than the carbonate group, and thus the diffusion distance of the anion can be further shortened. In other words, the sulfonate group provides an effect of shortening the diffusion distance of the acid, thereby improving the resolution.

[0058] In the anion of the above formula 1, Y is a linker connecting A and Z, and may be a divalent organic group, specifically, a divalent hydrocarbon radical substituted with at least one halogen atom.

[0059] The Y may be any one of C1-C10 alkylene groups substituted with an atomic group containing at least one halogen element. The halogen element may be F. Thus, according to an embodiment, in the anion of Formula 1, the Y may be any one of C1-C10 alkylene groups substituted with an atomic group containing at least one F. The longer the alkylene chain in Y that is not substituted with F, the more difficult it is to synthesize, and the more difficult it is to crystallize during purification and to remove impurities, making it difficult to ensure purity.

[0060] That is, in the anionic structure represented by Chemical Formula 1, when polar functional groups A and Z are bonded via Y, the acidity can be reduced when the atomic group of Y contains at least one halogen element. Specifically, Y may be any one of alkylene groups having 2 to 5 carbon atoms substituted with 2 to 4 F, in which case the shorter the alkylene chain that is not substituted with F, the more advantageous it may be for the efficiency of synthesis and purification. When Y has two F's, it may be advantageous in synthesis for them to be present on the left side of the carbon chain.

[0061] In addition, in the anion of the above Chemical Formula 1, the Z may be any one of a sulfonyloxy group (-SO3-) or a carbonyloxy group (-C(=O)O-). Specifically, the Z in the above Chemical Formula 1 may be a sulfonyloxy group (-SO3-). In this case, since the polarity of the sulfonyloxy group is relatively higher than that of the carbonyloxy group, the diffusion distance of the anion can be further shortened. Therefore, when A is a sulfonate group and Z is a sulfonyloxy group, the contrast can be improved more effectively.

[0062] In addition, in the anion of the above formula 1, the R may be a linear or cyclic aliphatic hydrocarbon group or a monocyclic or polycyclic aromatic hydrocarbon group. The R includes an electron-withdrawing group (EWG) as a substituent, and the greater the number of electron-withdrawing groups, the more advantageous effects on sensitivity can be provided.

[0063] The R may be any one of a cyclic aliphatic hydrocarbon group and an aromatic hydrocarbon group, specifically a monocyclic or polycyclic aromatic hydrocarbon group, more specifically a monocyclic aromatic hydrocarbon having 6 to 30 carbon atoms. That is, when the R is a cyclic aliphatic hydrocarbon group or a monocyclic or polycyclic aromatic hydrocarbon group, the absorption efficiency can be increased compared to when the R is a chain hydrocarbon group. In addition, when the R is a monocyclic aromatic group, there is an advantage that the solubility is increased. Therefore, it may be advantageous for the R to contain a monocyclic aromatic group in terms of absorption efficiency and solubility.

[0064] In this case, the linear or cyclic aliphatic hydrocarbon group of R is an alkyl group, an alkenyl group, a cycloalkyl group, or a cycloalkenyl group substituted with one or more electron-withdrawing groups (EWG), and the alkyl group and the alkenyl group are each independently a linear or branched group having 1 to 30 carbon atoms, and the cycloalkyl group or the cycloalkenyl group may each independently be a monocyclic or polycyclic group having 3 to 30 carbon atoms. In addition, in the anion of Formula 1, the EWG is an electron-withdrawing group that serves as an activity-reducing group substituted via -R.

[0065] The EWG is substituted and linked to a sulfonyloxy group via R, which can more effectively improve exposure sensitivity, ensure high contrast between exposed and unexposed areas, and improve limiting resolution.

[0066] In particular, when the anion of Formula 1 contains an aromatic sulfonyloxy group substituted with an electron-withdrawing group, it is possible to obtain a resist composition that has improved exposure sensitivity and high contrast between exposed and unexposed areas, improved resolution, and low line width roughness, thereby improving process margins, compared to a case where the anion does not contain an aromatic sulfonyloxy group.

[0067] Specifically, the EWG may be one or more electron-withdrawing groups selected from the group consisting of halogens; cyano groups; nitro groups; hydroxy groups; carbonyl groups; ester groups; imide groups; amide groups; amino groups; carboxy groups; sulfonic acid groups; sulfonamide groups; phosphine oxide groups; alkoxy groups; alkylcarbonyl groups; alkoxycarbonyl groups; sulfonyl groups; aryloxy groups; alkylthioxy groups; arylthioxy groups; alkylsulfoxy groups; arylsulfoxy groups; silyl groups; boron groups; and cycloalkyl groups.

[0068] Specifically, the EWG may be any one or more electron-withdrawing groups selected from a nitro group, a halogen, a fluoroalkyl group, a cyano group, and a sulfonyl group. The nitro group, the halogen, the fluoroalkyl group, the cyano group, and the sulfonyl group have higher absorption efficiency of the EUV light source than the electron-withdrawing groups exemplified above. Among these, the EWG may be any one selected from a halogen group, a sulfonyl group, and a nitro group, and the halogen group may have the highest absorption efficiency of the EUV light source. That is, the absorption efficiency of the EUV light source may be further improved in the order of the nitro group, the sulfonyl group, and the halogen group.

[0069] Thus, the EWG may be a halogen group or a sulfonyl group, more specifically, a sulfonyl group. The halogen may be F or I, and according to a preferred embodiment, it may be I.

[0070] According to an embodiment of the present invention, when R has an aromatic structure and contains a halogen element, particularly iodine, as an electron-withdrawing group (EWG), it can exhibit higher light absorption ability for an EUV light source, thereby further maximizing the improvement of resist performance.

[0071] The EWG may have a cycloalkyl group substituted or unsubstituted with at least one heteroatom. The EWG may also have a cycloalkyl group substituted with one or more heteroatoms having 3 to 30 carbon atoms substituted with a sulfonyl group, or a cycloalkyl group substituted with one or more heteroatoms having 4 to 10 carbon atoms substituted with a sulfonyl group. The heteroatom may be nitrogen or oxygen. For example, the EWG may have any one of the following structures:

[0072] JPEG2025500245000012.jpg29159

[0073] More specifically, in the structure of -R-EWG in Chemical Formula 1, the chain or cyclic aliphatic hydrocarbon or aromatic hydrocarbon of R may have an electron-withdrawing group by replacing at least one hydrogen atom of R.

[0074] Therefore, in the above Chemical Formula 1, -R-EWG may be an alkyl group (R) having 1 to 30 carbon atoms in which at least one hydrogen atom of the R of the chain aliphatic hydrocarbon is substituted with a halogen (EWG). Specific examples of the alkyl group having 1 to 30 carbon atoms are not particularly limited, but one example is one of methyl, ethyl, and propyl. Accordingly, specific examples of the alkyl group having 1 to 30 carbon atoms in which at least one hydrogen atom is substituted with a halogen, which is -R-EWG, are not particularly limited, but one example is trifluoromethyl in which a methyl group is substituted with a halogen.

[0075] In addition, in the structure of -R-EWG in Chemical Formula 1, the cyclic hydrocarbon may be a cycloalkyl group (R) having 3 to 30 carbon atoms in which at least one hydrogen atom of R is substituted with a halogen (EWG). Specific examples of the cycloalkyl group having 3 to 30 carbon atoms in which a hydrogen atom is substituted, which is -R-EWG, are not particularly limited, but include, for example, 4-fluorocyclohexyl.

[0076] In addition, in the structure of -R-EWG in Chemical Formula 1, the aromatic hydrocarbon is a monocyclic aryl group (R) having 6 to 30 carbon atoms in which at least one hydrogen atom is substituted with any one EWG selected from a nitro group, a halogen, a fluoroalkyl group, a cyano group, and a sulfonyl group.

[0077] Specific examples of the -R-EWG structure are not particularly limited, and examples thereof include any one of 4-trifluoromethylphenyl, 4-fluorophenyl, 2,5-difluorophenyl, 2,4-difluorophenyl, 2,3-difluorophenyl, 4-(trifluoromethyl)phenyl, 1,2,3,4,5-pentafluorophenyl, 4-bromophenyl, 4-iodophenyl, 3,5-diiodophenyl, 4-cyanophenyl, 4-nitrophenyl, and 4-sulfonylphenyl.

[0078] Specifically, in the above formula 1, when R is an aryl group having 6 to 30 carbon atoms in which 2 to 6 hydrogen atoms are substituted with halogen, it is advantageous in terms of improving absorption efficiency and solubility.

[0079] In the above formula 1, an example of -R-EWG may be one of methyl, ethyl, propyl, trifluoromethyl, cyclohexyl, adamantyl, 4-trifluoromethylphenyl, 4-fluorophenyl, 2,5-difluorophenyl, 2,4-difluorophenyl, 2,3-difluorophenyl, 4-(trifluoromethyl)phenyl, 1,2,3,4,5-pentafluorophenyl, 4-bromophenyl, 4-iodophenyl, 3,5-diiodophenyl, 4-cyanophenyl, 4-nitrophenyl, and 4-sulfonylphenyl, more specifically, 4-fluorophenyl, 4-bromophenyl, 4-iodophenyl, 2,4-difluorophenyl, 2,5-difluorophenyl, 2,3-difluorophenyl, 4-(trifluoromethyl)phenyl, or 1,2,3,4,5-pentafluorophenyl. However, the -R-EWG is not limited thereto and may include a structure included in an example of an anion described below. According to one embodiment of the present invention, the photoacid generator may be a compound represented by the following Chemical Formula 3: [Chemical formula 3]

[0080] JPEG2025500245000013.jpg30159 In the above formula 3, n is an integer from 1 to 10, R, E.W.G., and M. + is as defined above. That is, in the case of the above-mentioned Chemical Formula 3, as shown in the following structural formula 3-1, the anion portion of Chemical Formula 1 can be classified as AYZR-EWG. [Chemical formula 3-1]

[0081] JPEG2025500245000014.jpg52159

[0082] Specifically, as in the above-mentioned Chemical Formula 3 and 3-1, A in Chemical Formula 1 is a sulfonate group (-SO3 - ), Y is an alkylene group substituted with two or more F groups, and Z is a sulfonyloxy group (-SO3- ) may also be used.

[0083] In addition, in the above formulas 3 and 3-1, R is a monocyclic or polycyclic aromatic hydrocarbon group, and EWG, which is an electron-withdrawing group, may be any one or more selected from a halogen group, a nitro group, a halogen, a fluoroalkyl group, a cyano group, and a sulfonyl group. More specifically, R is a monocyclic aromatic hydrocarbon group, and EWG, which is an electron-withdrawing group, may be a halogen group.

[0084] In this case, the aromatic group (R) substituted with an electron-withdrawing group (EWG) is substituted for the sulfonyloxy group of Z, so that the absorption of electron beams and EUV photons is increased, and more secondary electrons can be generated in the resist thin film, thereby improving sensitivity. Also, as described above, when the aromatic structure (R) contains a halogen element, particularly iodine, which has a higher light absorption ability for the EUV light source, the improvement of resist performance can be maximized. Additionally, the electron-withdrawing group EWG may have a cycloalkyl group substituted with at least one heteroatom. In addition, n may be an integer of 1 or 2.

[0085] Specific examples of the anion represented by the above Chemical Formula 1 are not particularly limited, but may be any one selected from the group consisting of the following:

[0086] JPEG2025500245000015.jpg209167

[0087] As described above, the photoacid generator having a novel structure including an anion having a specific polar functional group of the above-mentioned formula 1 has an anion having a sulfonyloxy group including a substituent having an electron-withdrawing group, thereby improving polarity and shortening the diffusion length of the acid, thereby ensuring high contrast and improving the limit resolution. In addition, the photoacid generator has a low LER / LWR value and can simultaneously satisfy the improvement of CDU, and can be used as an effective resist material to provide a photoresist composition having a wide process margin.

[0088] In particular, in the case where R-EWG including an unsaturated aromatic group having an electron-withdrawing group is selected and substituted in the above Chemical Formula 1, the absorption of electron beams or EUV photons is increased, so that more secondary electrons can be generated in the resist thin film, improving sensitivity, and the improvement of resist performance can be maximized by including a halogen element having a higher light absorption ability for an EUV light source.

[0089] On the other hand, in the above formula 2, M + may be one of an onium ion or a metal ion. + may be one of the onium ions, sulfonium ion, iodonium ion, or ammonium ion.

[0090] Specific examples of the cation represented by the above formula 2 are not particularly limited, but may be any one selected from the group consisting of the following:

[0091] JPEG2025500245000016.jpg223159 The specific example of the method for synthesizing the salt compound is not particularly limited, but as an example, the salt compound may be synthesized according to the following reaction formula 1. [Reaction Scheme 1]

[0092] JPEG2025500245000017.jpg95159

[0093] In Reaction Scheme 1, R, M, EWG, and n are the same as those defined in the onium salt-containing compounds including Formula 1 and Formula 2, X is a counter anion and is a halogen element, and base is an organic base.

[0094] First, compound 1-a can be reduced and hydrolyzed to obtain compound 1-b, which can then be reacted again with compound 1-c or compound 1-d under basic conditions to obtain compound 3.

[0095] In the reduction reaction for obtaining the compound 1-b, an alcohol group can be obtained from an ester group using a reducing agent that generates an appropriate hydrogen ion. The reducing agent is not particularly limited, and generally, sodium borohydride (NaBH4), lithium aluminum hydride (LiAlH4), diisobutyl aluminum hydride (DIBAH), etc. may be used, and the amount of the reducing agent used may be 1 to 1.5 moles per mole of the compound 1-a.

[0096] In addition, the compound and the method used to provide the cation of compound 1-b through the hydrolysis are not particularly limited, and a suitable onium ion or metal ion-containing compound well known in the art can be used, and the compound can be dissolved in a suitable organic solvent and water together with the reduction product of compound 1-a, reacted, and then stirred so that the organic layer and the aqueous layer are thoroughly mixed to obtain the compound.

[0097] After the reduction reaction, the subsequent hydrolysis reaction can be carried out by reacting with an appropriate alkali metal hydroxide. The alkali metal hydroxide is not particularly limited, and general sodium hydroxide, potassium hydroxide, etc. can be used, and the amount of the alkali metal hydroxide used can be 1 to 1.5 moles per mole of compound 1-a.

[0098] In the reaction, the organic solvent may be a solvent capable of dissolving the product 1-b and the onium salt-containing compound well, such as dichloromethane, chloroform, or acetonitrile. The amount of the organic solvent used may be 5 parts by weight or more and 20 parts by weight or less, based on each compound.

[0099] The amount of the compounds 1-c and 1-d used in the reaction may usually be 1 to 2 moles per mole of the compound 1-b. The reaction time varies depending on the reactivity and reaction concentration, but may usually be 10 to 24 hours, and the reaction temperature may be 0°C to 25°C.

[0100] After completion of the reaction, the aqueous layer and the organic layer are separated, and the reaction product dissolved in the organic layer can be purified by a method selected from conventionally known purification methods such as solvent extraction, concentration, chromatography, crystallization, and recrystallization, either alone or in combination. This method can be applied to the purification of not only the final compound (3) but also compounds 1-d, 1-g, and 1-h synthesized in each step.

[0101] Photoresist Composition Meanwhile, according to another embodiment of the present invention, there is provided a photoresist composition including the novel photoacid generator of the above embodiment, a base polymer, an acid diffusion inhibitor, and an organic solvent.

[0102] The content of the photoacid generator includes the content described above with respect to the embodiment. The content of the photoacid generator may be 1 to 90 parts by weight, preferably 5 to 80 parts by weight, more preferably 10 to 70 parts by weight, based on 100 parts by weight of the base polymer. If the content of the photoacid generator is 1 part by weight or less, the content is too small, so that the amount of acid generated as an anion is insufficient, and the sensitivity to light is weakened, and not only the resolution but also the performance of the resist pattern is deteriorated. If the content of the photoacid generator is more than 90 parts by weight, the sensitivity to light is increased, but a large amount of acid is generated in the exposed area, making it difficult to control the diffusion distance of the acid, and the pattern may be defective. In addition, in order to improve the resolution and the formation of the resist pattern and to optimize the increase in the amount of acid generated by the anion and the sensitivity to light, the content of the photoacid generator may be 5 to 80 parts by weight or 10 to 70 parts by weight. Meanwhile, the resist composition of the present invention contains the onium salt photoacid generator compound and a polymer resin component whose solubility in a developer can be changed by the action of an acid.

[0103] The base polymer has a property that its solubility in a developer changes under the action of an acid, and any alkali-soluble photosensitive polymer used in a typical photoresist composition can be used without any restrictions.

[0104] As a specific example, the base polymer may include a repeating unit represented by the following chemical formula a or chemical formula b. The base polymer may be a homopolymer consisting of one type of repeating unit represented by the chemical formula a, a homopolymer consisting of one type of repeating unit represented by the chemical formula b, a copolymer consisting of two or more types of repeating units represented by the chemical formula a, a copolymer consisting of two or more types of repeating units represented by the chemical formula b, or a copolymer consisting of one or more types of repeating units represented by the chemical formula a and one or more types of repeating units represented by the chemical formula b. [Chemical formula a]

[0105] JPEG2025500245000018.jpg33159

[0106] In the above chemical formula a, R1 may be hydrogen or a methyl group, and Ar may be an aryl group in which at least one hydrogen atom is substituted or unsubstituted. The aryl group may be a monocyclic or polycyclic ring. Examples of the substituent are not particularly limited, and include one or more substituents selected from the group consisting of deuterium, halogen, cyano group, nitro group, hydroxy group, carbonyl group, ester group, imide group, amide group, amino group, carboxy group, sulfonic acid group, sulfonamide group, phosphine oxide group, alkoxy group, alkylcarbonyl group, alkoxycarbonyl group, sulfonyloxy group, aryloxy group, alkylthiooxy group, arylthiooxy group, alkylsulfoxy group, arylsulfoxy group, silyl group, and boron group. More specifically, the substituent may be a halogen or a hydroxy group. [Chemical formula b]

[0107] JPEG2025500245000019.jpg58159

[0108] In the above formula b, R2 is hydrogen or a methyl group, and R3 may be one of an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, and an aryl group. At least one hydrogen atom contained in the alkyl group, the alkenyl group, the cycloalkyl group, the cycloalkenyl group, and the aryl group may be independently substituted or unsubstituted with one or more substituents selected from the group consisting of deuterium, halogen, cyano group, nitro group, hydroxy group, carbonyl group, ester group, imide group, amide group, amino group, carboxy group, sulfonic acid group, sulfonamide group, phosphine oxide group, alkoxy group, alkylcarbonyl group, alkoxycarbonyl group, sulfonyloxy group, aryloxy group, alkylthiooxy group, arylthiooxy group, alkylsulfoxy group, arylsulfoxy group, silyl group, and boron group.

[0109] At least one or more carbon atoms contained in the alkyl group, alkenyl group, cycloalkyl group, cycloalkenyl group, and aryl group may each independently be substituted or unsubstituted with a heteroatom.

[0110] The alkyl group and the alkenyl group may each independently be linear or branched, and the cycloalkyl group, the cycloalkenyl group and the aryl group may each independently be monocyclic or polycyclic. More specifically, the base polymer may be a photosensitive polymer (base resin) represented by the following chemical formula c. [Chemical formula c]

[0111] JPEG2025500245000020.jpg49160

[0112] In the formula c, R4 to R6 are the same or different and each independently represent hydrogen or a methyl group, Ar is an aryl group in which at least one hydrogen atom is substituted or unsubstituted, and R7 and R8 are the same or different and each independently represent one of an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, or an aryl group. Ar is the same as Ar in the formula a, and R7 and R8 are the same as R3 in the formula b.

[0113] More specifically, in the above chemical formula c, Ar may be a monocyclic aryl group having 6 to 11 carbon atoms in which at least one hydrogen atom is substituted with a hydroxy group.

[0114] In the above formula c, R7 may be a monocyclic or polycyclic cycloalkyl group in which at least one carbon atom is substituted with a heteroatom, or a polycyclic cycloalkyl group in which at least one hydrogen atom is substituted with a hydroxyl group. In the above formula c, R8 may be a monocyclic or polycyclic cycloalkyl group.

[0115] In the formula c, a, b, and c written under the repeating unit are the mol% of each repeating unit with respect to the total monomers (repeating units) constituting the polymer, where a may be 10 mol% to 60 mol%, or 35 mol% to 40 mol%, b may be 1 mol% to 30 mol%, or 5 mol% to 20 mol%, and c may be 30 mol% to 60 mol%, or 40 mol% to 55 mol%. If the mol% of the repeating unit is outside the above range, the physical properties of the photoresist film may be deteriorated, or it may be difficult to form the photoresist film, and the contrast of the pattern may be reduced. Typically, the weight average molecular weight (Mw) of the photosensitive polymer may be 2,000 to 20,000, or 3,000 to 12,000.

[0116] More specific examples of the photosensitive polymer (base resin) represented by the above chemical formula c include photosensitive polymers (base resins) represented by the following chemical formulas d and e, but are not limited thereto. [Chemical formula d]

[0117] JPEG2025500245000021.jpg42160 [Chemical formula e]

[0118] JPEG2025500245000022.jpg41160

[0119] The content of the base polymer may be 2 to 30% by weight, or 4 to 10% by weight, based on the total weight of the photoresist composition. If the content of the base polymer is less than 2% by weight, it may be difficult to form a photoresist film and a pattern, and if it exceeds 30% by weight, the thickness distribution of the pattern formed on the wafer may not be uniform.

[0120] Meanwhile, the photoresist composition according to an embodiment of the present invention may or may not additionally contain an acid diffusion control agent (i.e., a quencher) to improve resist performance. Specifically, the photoresist composition may contain an acid diffusion inhibitor.

[0121] Examples of the acid diffusion inhibitor include conventional basic compounds such as primary, secondary, and tertiary aliphatic or aromatic amines, alcoholic nitrogen-containing compounds, amides, imides, covermates, etc. By adding such basic compounds as an acid diffusion inhibitor, the diffusion speed of the acid in the resist thin film can be controlled to correct and adjust the shape of the pattern.

[0122] In addition, instead of the alcoholic nitrogen-containing organic compound, a photodecomposable acid diffusion inhibitor that has a structure similar to that of the photoacid generator and is decomposed by an exposure source may be used. Such a photodecomposable acid diffusion inhibitor acts as a quencher that suppresses acid diffusion in non-exposed areas, and is photodecomposed in exposed areas to act as an acid, thereby maintaining the acid concentration in the exposed areas relatively high and increasing the acid distribution contrast between the exposed and non-exposed areas, thereby improving lithography characteristics. The photodecomposable acid diffusion inhibitor may be a sulfonium salt or an iodonium salt of a carboxylic acid, a non-fluorinated sulfonic acid, or an N-sulfonylimide acid, which may be used alone or in combination of two or more kinds. In addition to the above-mentioned quencher, base polymer resin, and acid generator, other components such as an organic solvent, a surfactant, and a dissolution inhibitor may be appropriately combined to form a resist material.

[0123] The content of the acid diffusion inhibitor may be 1 part by weight or more and 90 parts by weight or less, preferably 5 parts by weight or more and 80 parts by weight or less, more preferably 10 parts by weight or more and 70 parts by weight or less, based on 100 parts by weight of the base polymer. If the content of the photoacid diffusion inhibitor is 1 part by weight or less, the sensitivity to light increases, but the content is too small, making it difficult to adjust the diffusion distance of the generated acid, and the pattern contrast of the exposed / non-exposed parts decreases, and if the content exceeds 90 parts by weight, the sensitivity to light decreases, the exposure sensitivity may slow down, or a decrease in resolution may occur. In addition, in order to optimize the increase in sensitivity to light, the pattern contrast of the exposed and non-exposed parts, the adjustment of the diffusion distance of the acid, and the improvement of resolution, the content of the acid diffusion inhibitor may be 5 parts by weight or more and 80 parts by weight or less, or 10 parts by weight or more and 70 parts by weight or less.

[0124] The organic solvent used in the present invention can be any organic solvent that is capable of easily dissolving the base polymer, the photoacid generator, the acid diffusion inhibitor, other additives, and the like, and is used in ordinary photoresist compositions, without any limitations. For example, ketones such as cyclohexanone and methyl amyl ketone, alcohols such as 2-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol, ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, and diethyl glycol dimethyl ether, esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol mono tert-butyl ether acetate, and lactones such as γ-butyrolactone may be used alone or in a mixture of two or more, but are not limited thereto. The organic solvent is not particularly limited, but may be, for example, any one of PGMEA (propylene glycol monomethyl ether acetate), PGME (propylene glycol monomethyl ether), EL (ethyl lactate), and CyH (cyclohexanone), which have the best solubility for the acid diffusion inhibitor, or a mixture thereof.

[0125] The content of the organic solvent is the remainder excluding the content of the photoresist composition excluding the base polymer, the photoacid generator, the salt compound, and other additives, with respect to 100% by weight of the entire photoresist composition.

[0126] Examples of the additives are not particularly limited, but may include, for example, additional resins, stabilizers, surfactants, thickeners, defoamers, adhesion promoters, antioxidants, and dissolution inhibitors.

[0127] Method for forming photoresist pattern According to yet another embodiment of the present invention, there may be provided a method for forming a photoresist pattern, the method including: applying and heating the photoresist composition of the other embodiment to form a photoresist film; exposing the photoresist film; and developing the exposed photoresist film to form a photoresist pattern. The content of the photoresist composition includes the content described above in relation to the other embodiments.

[0128] The pattern can be formed by applying a known technique, for example, by coating the photoresist using a spinner or the like, exposing the photoresist film to high-energy rays with a wavelength of 300 nm or less using a predetermined photomask, and developing the exposed photoresist film with a normal developer (for example, an alkaline aqueous solution such as a tetramethylammonium hydroxide aqueous solution having a concentration of 0.1% by weight to 10% by weight).

[0129] Specifically, the method for forming the pattern includes the steps of applying the above-mentioned photoresist composition onto a silicon wafer substrate, heating the applied substrate to form a resist thin film, exposing the resist thin film to a selected high energy exposure source, eliminating acid labile groups in a polymer resin by acid generated at the exposed area, and developing the resist thin film with changed solubility with the developer to form a pattern.

[0130] The high-energy radiation having a wavelength of 300 nm or less is not particularly limited, but examples thereof include ultraviolet rays, far ultraviolet rays, extreme ultraviolet rays (EUV), electron beams, X-rays, excimer lasers, gamma rays, synchrotron radiation, etc. For the formation of fine patterns of 70 nm or less, it is preferable to use an exposure device equipped with a source of short-wavelength high-energy radiation such as an ArF excimer laser, a KrF excimer laser, or EUV.

[0131] More specifically, the high energy exposure source may be selected from KrF having a wavelength of 248 nm, ArF having a wavelength of 193 nm, an electron beam (e-beam), and EUV having a wavelength of 13.5 nm. Effect of the Invention

[0132] The photoacid generator according to the present specification can be used as an effective resist material to provide a photoresist composition having a wide process margin while simultaneously satisfying the improvement of CDU by improving the polarity and shortening the diffusion length of acid, thereby ensuring high contrast and improving the limiting resolution, and having a low LER / LWR value.

[0133] In addition, the greater absorption of electron beams and EUV photons allows more secondary electrons to be generated in the resist thin film, improving sensitivity, and the inclusion of halogen elements, especially iodine, which have a higher absorption capacity for EUV light sources, can maximize the improvement of resist performance. [Brief description of the drawings]

[0134] [Figure 1] FIG. 1 shows 1H NMR data of photoacid generator 1 of Synthesis Example 1 according to a preferred embodiment. [Diagram 2] FIG. 2 shows 1H NMR data of photoacid generator 2 of Synthesis Example 2 according to a preferred embodiment. [Diagram 3] FIG. 3 shows 1H NMR data of photoacid generator 3 of Synthesis Example 3 according to a preferred embodiment. BEST MODE FOR CARRYING OUT THE INVENT

[0135] Examples are presented below for the understanding of the present invention. However, the following examples are merely for illustrating the present invention and are not intended to limit the present invention thereto.

[0136] <Synthesis Examples 1 to 9: Production of Photoacid Generators> Synthesis Example 1: Production of Photoacid Generator 1 Synthesis Example 1-1: Synthesis of sodium 1,1-difluoro-2-methoxy-2-oxoethanesulfonate

[0137] JPEG2025500245000023.jpg53160

[0138] In a 3L round-bottom flask, 300g of methyl 2-(fluorosulfonyl)difluoroacetate was slowly added dropwise to a 5N aqueous sodium hydroxide solution, and the mixture was stirred for 3 hours. The pH was adjusted to 3-5 with a 10% aqueous hydrochloric acid solution, and the water used as the solvent was removed by distillation under reduced pressure. Then, 1200g of methanol was added to the flask containing the product distilled under reduced pressure to dissolve the product. Then, 25g of sulfuric acid was slowly added dropwise, and the temperature was raised to 65°C, followed by stirring for 12 hours.

[0139] After the reaction was completed, insoluble inorganic substances (i.e., inorganic salts that did not participate in the reaction) were removed by filtration, and the mixture was concentrated under reduced pressure. 1 L of a 2:1 (volume ratio) mixed solvent of methanol / ethanol was added again, and insoluble inorganic salts were further removed by filtration. The mixture was then concentrated under reduced pressure to obtain 285.7 g (yield 95.29%) of 1,1-difluoro-2-methoxy-2-oxyethanesulfonate sodium salt without further purification. 600MHz 1 H-NMR (DMSO_d6, TMS): 3.78 (CH3, s, 3H) Synthesis Example 1-2: Synthesis of 1,1-difluoro-2-hydroxyethanesulfonate sodium salt

[0140] JPEG2025500245000024.jpg19160

[0141] 280 g of 1,1-difluoro-2-methoxy-2-oxyethanesulfonate sodium salt obtained through Synthesis Example 1-1 was placed in a 3 L round bottom flask (reactor), and 0.6 L of methanol and 1.5 L of tetrahydrofuran were added to dissolve, and the reactor was cooled to -10° C. Then, 175 g of sodium borohydride was slowly added to the reactor, and the temperature was raised to room temperature and stirred, and the temperature was raised again to 60° C. and stirred for 24 hours.

[0142] After the reaction was completed, the reaction solution was acidified to pH 3-5 using concentrated hydrochloric acid, and the insoluble inorganic matter was filtered off and the solvent was concentrated under reduced pressure to remove it. Then, 1 L of a 2:1 (volume ratio) mixed solvent of methanol / ethanol was added again, and the insoluble inorganic salts were further filtered off and removed. The solvent was concentrated under reduced pressure to obtain 237.2 g (yield 97.6%) of sodium 1,1-difluoro-2-hydroxyethanesulfonate salt without further purification. 600MHz 1 H-NMR (D2O, TMS): 4.12 (CH2, t, 2H)

[0143] Synthesis Example 1-3: Synthesis of 1,1-difluoro-2-hydroxyethanesulfonate triphenylsulfonium salt

[0144] JPEG2025500245000025.jpg35168 150g of sodium 1,1-difluoro-2-hydroxyethanesulfonate obtained in Synthesis Example 1-2 and 268g of triphenylsulfonium chloride were placed in a 2,000L round bottom flask, and 1,000g of dichloromethane and 200g of distilled water were added to dissolve the mixture. The mixture was stirred at room temperature for 12 hours, and the organic layer was separated and then distilled under reduced pressure.

[0145] The solid product obtained by vacuum distillation was dissolved by adding 800 g of ethanol, and the insoluble inorganic salts were removed by filtration. The solid was solidified using 5 L of diethyl ether, and the mixture was stirred for an additional hour, filtered, and dried to obtain 321.6 g of 1,1-difluoro-2-hydroxyethanesulfonate triphenylsulfonium salt (yield 92.98%). 600MHz 1 H-NMR (CDCl3, TMS): 7.75 (CH, m, 15H), 4.05 (CH2, t, 2H), 3.6 (OH)

[0146] Synthesis Example 1-4: Synthesis of 1,1-difluoro-2-(4-iodophenylsulfonyloxy)ethanesulfonate triphenylsulfonium salt

[0147] JPEG2025500245000026.jpg36168

[0148] 200g of 1,1-difluoro-2-hydroxyethanesulfonate triphenylsulfonium salt obtained through Synthesis Example 1-3 was placed in a 3L round-bottom flask, and 1,200g of dichloromethane was added to dissolve it, and then 57g of triethylamine was diluted in 300g of dichloromethane and added to the flask. Then, 171g of 4-iodophenylsulfonyl chloride was dissolved in 1,200g of dichloromethane solvent and slowly added for 1 hour, and then stirred at room temperature for 5 hours. Then, the produced sodium chloride was removed by filtration, and the organic layer was washed with 1,500g of distilled water three times, and the organic layer was separated and distilled under reduced pressure.

[0149] The resulting solid product was dissolved by adding 600 g of methanol, solidified with 5 L of diethyl, stirred for an additional hour, filtered, and dried to obtain 296.8 g (yield 91.22%) of 1,1-difluoro-2-(4-iodophenylsulfonyloxy)ethanesulfonate triphenylsulfonium salt.

[0150] 600MHz 1 H-NMR (DMSO_d6): 8.07 (CH, d, 2H), 7.80 (CH, m, 15H), 7.69 (CH, d, 2H), 4.49 (CH2, t, 2H)

[0151] Synthesis Example 2: Production of Photoacid Generator 2 Synthesis of 1,1-difluoro-2-(4-trifluoromethanephenylsulfonyloxy)ethanesulfonate triphenylsulfonium salt

[0152] JPEG2025500245000027.jpg34168

[0153] The remaining reactions were carried out in the same manner as in Synthesis Examples 1-1 to 1-4, except that 138 g of 4-trifluoromethanephenylsulfonyl chloride was used instead of 4-iodophenylsulfonyl chloride in Synthesis Example 1-4, to obtain 268.36 g (yield 88.35%) of 1,1-difluoro-2-trifluoromethanephenylsulfonyloxyethanesulfonate triphenylsulfonium salt.

[0154] 600MHz 1 H-NMR(CD3)2CO, TMS): 8.25(CH, d, 2H), 8.15(CH, d, 2H), 7.90(CH, m, 15H), 4.64(CH2, t, 2H)

[0155] Synthesis Example 3: Production of Photoacid Generator 3 Synthesis of 1,1,2,2-tetrafluoro-3-iodophenylsulfonyloxyethanesulfonate triphenylsulfonium salt

[0156] JPEG2025500245000028.jpg34168

[0157] In the above Synthesis Example 1-1, 150 g of methyl 2,2,3,3-tetrafluoro-3-(fluorosulfonyl)propanoate was used instead of methyl 2-(fluorosulfonyl)difluoroacetate as a starting material, and the remaining reactions were carried out in the same manner as in Synthesis Example 1-1 to Synthesis Examples 1 to 4, to obtain 213.45 g (yield 91.2%) of 1,1,2,2-tetrafluoro-3-iodophenyloxyethanesulfonate triphenylsulfonium salt.

[0158] 600MHz 1 H-NMR (CD3)2CO, TMS): 8.12 (CH, d, 2H), 7.90 (CH, m, 15H), 7.49 (CH, d, 2H), 4.60 (CH2, t, 2H)

[0159] Synthesis Examples 4 to 16: Preparation of Photoacid Generators 4 to 16 By applying the methods of Synthesis Examples 1 to 3, and by changing the type of starting material of Synthesis Example 1-1, the cationic compound of Synthesis Example 1-3, and the anionic -R-EWG-providing compound of Synthesis Example 1-4, the following anionic compounds having a sulfonyloxy group or a carbonyloxy group as substituents were prepared. Then, the above anionic compounds were subjected to an ion exchange reaction with sulfonium chlorides having the following cations to prepare photoacid generators 4 to 16 having the following structures, respectively.

[0160] Photoacid generator 4:

[0161] JPEG2025500245000029.jpg37168

[0162] Yield: 72.52%, 600MHz 1 H-NMR (CDCl3, TMS): 8.02 (CH, d, 2H), 7.91 (CH, d, 2H), 7.52 (CH, m, 10H), 7.33 (CH, 2H), 7.11 (CH, 2H), 5.56 (OH), 4.43 (CH2, t, 2H)

[0163] Photoacid generator 5:

[0164] JPEG2025500245000030.jpg62159

[0165] Yield: 78.35%, 600MHz 1 H-NMR (CDCl3, TMS): 8.24 (CH, d, 2H), 7.92 (CH, 2H), 7.70 (CH, d, 2H), 7.40~7.48 (CH, m, 12H), 6.85~7.30 (CH, m, 4H), 7.11 (CH, 2H), 4.44 (CH2, t, 2H)

[0166] Photoacid generator 6:

[0167] JPEG2025500245000031.jpg32159

[0168] Yield: 75.10%, 600MHz1 H-NMR (CDCl3, TMS): 8.11~8.22 (CH, m, 4H), 7.48 (CH, m, 15H), 4.56 (CH2, t, 2H), 3.70 (CH2, m, 4H), 3.02 (CH2, m, 4H)

[0169] Photoacid stimulant 7:

[0170] JPEG2025500245000032.jpg45159

[0171] Yield: 87.50%, 600MHz 1 H-NMR (CDCl3, TMS): 8.12 (CH, d, 1H), 7.92 (CH, d1H), 7.75 (CH, t, 1H), 7.40~7.80 (CH, m, 8H), 6.98~7.32 (CH, m, 4H), 5.40 (OH), 4.48 (CH2, t, 2H)

[0172] Photoacid generator 8:

[0173] JPEG2025500245000033.jpg40159

[0174] Yield: 78.38%, 600MHz 1 H-NMR (CDCl3, TMS): 8.02 (CH, d, 2H), 7.84 (CH, d, 2H), 7.40~7.80 (CH, m, 8H), 6.96~7.30 (CH, m, 4H), 5.20 (OH), 4.02 (CH2, t, 2H)

[0175] Photoacid treatment agent 9:

[0176] JPEG2025500245000034.jpg38159

[0177] Yield: 80.85%, 600MHz 1 H-NMR (CDCl3, TMS): 7.92 (CH, d, 1H), 7.45~7.60 (CH, m, 17H), 3.94 (CH2, t, 2H)

[0178] Photoacid generator 10:

[0179] JPEG2025500245000035.jpg41159

[0180] Yield: 85.27%, 600MHz 1 H-NMR (CDCl3, TMS): 7.96~8.10 (CH, m, 4H), 7.49 (CH, m, 15H), 4.52 (CH2, t, 2H)

[0181] Photoacid generator 11:

[0182] JPEG2025500245000036.jpg42159

[0183] Yield: 86.62%, 600MHz 1 H-NMR (CDCl3, TMS): 8.44 (CH, d, 2H), 8.10 (CH, d, 2H), 7.50 (CH, m, 15H), 4.56 (CH2, t, 2H)

[0184] Photoacid generator 12:

[0185] JPEG2025500245000037.jpg39159

[0186] Yield: 83.18%, 600MHz 1 H-NMR (CDCl3, TMS): 8.15~8.30 (CH, m, 4H), 7.48 (CH, m, 15H), 4.48 (CH2, t, 2H), 3.30 (CH2, t, 4H), 1.94 (CH2, t, 4H)

[0187] Photoacid generator 13:

[0188] JPEG2025500245000038.jpg45159

[0189] Yield: 77.92%, 600MHz 1H-NMR (CDCl3, TMS): 7.48 (CH, m, 15H), 4.02 (CH2, t, 2H)

[0190] Photoacid generator 14:

[0191] JPEG2025500245000039.jpg38159

[0192] Yield: 72.16%, 600MHz 1 H-NMR (CDCl3, TMS): 7.48 (CH, m, 15H), 4.48 (CH2, t, 2H), 3.40~3.60 (CH, m, 2H), 2.96 (CH, m, 1H), 1.40~2.40 (CH2, m, 6H)

[0193] Photoacid generator 15:

[0194] JPEG2025500245000040.jpg44163

[0195] Yield: 83.22%, 600MHz 1 H-NMR (CDCl3, TMS): 8.04 (CH, d, 2H), 7.38~7.48 (CH, m, 17H), 5.04 (CH2, t, 2H)

[0196] Photoacid generator 16:

[0197] JPEG2025500245000041.jpg44163

[0198] Yield: 85.15%, 600MHz 1 H-NMR (CDCl3, TMS): 7.84~7.92 (CH, m, 4H), 7.48 (CH, m, 15H), 5.04 (CH2, t, 2H) The structures of the photoacid generators according to Synthesis Examples 1 to 16 are shown in Table 1 below.

[0199] [Table 1] JPEG2025500245000043.jpg229159JPEG2025500245000044.jpg84158

[0200] <Synthesis Examples 2 and 3: Synthesis of Base Polymers (Polymers 1 and 2)> Monomers were combined to have the repeating units shown in Table 2 below, and copolymerization was carried out in tetrahydrofuran (THF) solvent. After that, the reaction solution was immersed in a dropwise addition of a mixed solvent of methanol, n-hexane, hexane / isopropyl alcohol, or methanol / water to remove small molecules and solidify the solution, and then repeatedly washed with the same solvent and separated and dried to produce base polymers 1 and 2 containing hydroxystyrene groups in the aromatic ring.

[0201] The hydroxystyrene group-containing group can be obtained by using a monomer protected with an acetoxy group, carrying out a secondary hydrolysis reaction after a primary polymerization, and then adding a precipitation process using water.

[0202] The composition of base polymers 1 and 2 after drying is 1 H or 13 The monomer components were analyzed by C-NMR spectroscopy, and Mw and PDI (Mw / Mn) were analyzed by gel permeation chromatography (GPC) using THF solvent and standard polystyrene molecular weight conversion. The types of repeat units and analytical results of polymers 1 and 2 are listed in Table 2 below.

[0203] [Table 2]

[0204] <Examples 1 to 25 and Comparative Examples 1 to 12> Preparation of the photoresist composition According to the composition in Table 3 below, 100 parts by weight of base polymer and selected components (25 parts by weight of photoacid generator and 15 parts by weight of quencher) were prepared, and these were dissolved and mixed in an organic solvent in Table 3 below. Then, the mixture was filtered through a polytetrafluoroethylene (PTFE) filter having pores of 0.2 μm size to prepare photoresist compositions of the examples and comparative examples.

[0205] <<Base polymer>> In the examples and comparative examples, Paysporlimo selected one of the polymers 1 and 2 prepared in the above Synthesis Examples 2 and 3 and used it.

[0206] <<Photoacid generator>> In Examples 1 to 25, one of the photoacid generators 1 to 16 was selected and used. In Comparative Examples 1 to 12, one of the photoacid generators A to E having the following structures was selected and used. Photoacid generator A:

[0207] JPEG2025500245000046.jpg41163 Photoacid generator B:

[0208] JPEG2025500245000047.jpg42159Photoacid generator C:

[0209] JPEG2025500245000048.jpg44159 Photoacid generator D:

[0210] JPEG2025500245000049.jpg36159Photoacid generator E:

[0211] JPEG2025500245000050.jpg37159

[0212] <<Quencher; Salt compound>> In the examples and comparative examples, one of quencher A and quencher B having the following structures was selected and used. Quencher A:

[0213] JPEG2025500245000051.jpg37159Quencher B:

[0214] JPEG2025500245000052.jpg36163

[0215] <<Organic solvents>> In the examples and comparative examples, one or more organic solvents selected from the following were used. PGMEA (Propylene glycol monomethyl ether acetate) PGME (Propylene glycol monomethyl ether) EL (Ethyl Lactate) CyH (cyclohexanone) experiment example

[0216] Resist pattern formation In order to analyze the resist pattern characteristics, a silicon wafer was coated with an organic thin film under the resist to prepare a substrate, and the photoresist compositions of the examples and comparative examples were spin-coated on the substrate to form a resist thin film. The substrate was then heated at 100°C to 130°C for 60 seconds using a hot plate to perform soft baking (SOB), (i) exposed to light using an ASML NXE:3400 EUV exposure device with a numerical aperture (NA) of 0.33, and then heated at 100°C to 130°C for 60 seconds (post exposure bake, PEB). The heated wafer was developed for 30 seconds with a 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution to form a 1:1 line and space (L / S: line / space) pattern with a film thickness size of 35 nm and a line width size of 18 nm. At this time, the SOB and PEB during the formation of the patterns in the examples and comparative examples were 100°C.

[0217] To measure the size of the pattern formed on the wafer by the above method, a Hitachi High-Technologies Corp. Critical Dimension Scanning Electron Microscope (CD-SEM, product name: CG-5000) was used to measure the size of the pattern, and the sensitivity, line width roughness (LER), and process margin (EL: energy latitude, DOF: depth of focus) were evaluated by the following methods. The evaluation results are shown in Table 1.

[0218] Evaluation of resist pattern characteristics (1) Sensitivity evaluation (unit: mJ / cm 2 ) The optimum exposure energy (Eop, unit mJ / cm) for forming a resist pattern having the same size space (pitch 18 nm) for a resist line width of 18 nm. 2 The lower the sensitivity value, the better the evaluation.

[0219] (2) LER / LWR evaluation (Line Edge Roughness / Line Width Roughness; unit: nm) For an 18 nm pattern formed with optimal exposure energy (Eop), the line edge roughness / line width roughness in the line width pattern length direction was measured at 200 measurement points, and the roughness magnitude (nm) was calculated as the average value for three times the standard deviation (s) (3s) of the measured values. The lower the LWR value, the better the evaluation.

[0220] (3) Evaluation of EL margin: EL (Exposure Latitude, unit: %) The EL margin (process margin) was calculated using the exposure energy value when a pattern of 18 nm size was formed with the optimal exposure energy (Eop) and the line width was formed within the range of 18 nm ± 5% (17.1 nm to 18.9 nm) according to the following formula. The higher the EL margin value, the better the evaluation. [Formula 1] EL margin (%) = (|E1-E2| / E op ) x 100 In the above formula 1, E1 is the exposure energy value (mJ / cm) when a pattern with a line width of 17.1 nm is formed. 2 ) and E2 is the exposure energy value (mJ / cm) when a pattern with a line width of 18.9 nm is formed. 2 ).

[0221] (4) Evaluation of DOF margin: DOF (Depth of focus, unit: nm) At the optimal exposure energy (Eop), the change in depth of focus (DOF) (±) was evaluated as the DOF margin, which was within the range of ±1.5% (17.73 nm to 18.27 nm) of the pattern line width of 18 nm. In other words, the DOF margin evaluation was calculated using the following formula 2. The higher the DOF margin value, the better the evaluation. [Formula 2] DOF margin (nm) = D1 + D2

[0222] In the above formula 2, D1 is the depth of focus value (nm) when a pattern with a line width of ±1.5% is formed, D2 is the depth of focus value (nm) when a pattern with a line width within ±1.5% is formed.

[0223] [Table 3] JPEG2025500245000054.jpg147166

[0224] From the results in Table 3, it was confirmed that Examples 1 to 25 exhibited lower sensitivity and LWR and higher EL and DOF process margins than Comparative Examples 1 to 12.

[0225] That is, when the photoresist compositions of Examples 1 to 25 were used, a compound of Chemical Formula 1 in which Y contains an alkylene group having 2 to 5 carbon atoms and 2 to 4 F groups substituted thereon, A contains a sulfonate group, Z contains a sulfonyloxy group or a carbonyloxy group, and contains an R-EWG having a specific structure at its terminal was used as a photoacid generator, and a photoirradiation efficiency of 51 mJ / cm was achieved. 2 More than 66mJ / cm 2 The following sensitivity was shown, LWR of 3.25 to 3.71 nm, EL margin of 10.2% to 11.8%, and excellent DOF margin of 90 to 110 nm. In this regard, Examples 1 to 13 and Examples 17 to 25 showed a relatively shorter acid diffusion distance and a more excellent effect than Examples 15 and 16 in which Z in Chemical Formula 1 contains a sulfonyloxy group, A is a sulfonate group, and Z is a carbonyloxy group. In addition, Examples 14 to 16 showed a similar sensitivity to the Comparative Example, but had lower LWR and EL than the Comparative Example, and had excellent DOF process margin, and thus could improve resist performance compared to the Comparative Example.

[0226] In contrast, when the photoresist compositions of Comparative Examples 1 to 12 were used, the radiation intensity was 62 mJ / cm 2 More than 68mJ / cm 2 The following Examples showed generally higher sensitivity. In particular, Comparative Examples 1 to 12 showed LWR of 3.80 nm to 4.31 nm, EL margin of 8.8% to 9.8%, and DOF margin of 80 nm to 95 nm, and were confirmed to have poor physical properties compared to the above Examples.

[0227] From these results, the above examples have lower sensitivity and LWR than the comparative examples, and can improve both the EL and DOF process margins. Therefore, they can be suitably used as chemically amplified resist compositions having high resolution, and can contribute to improving the performance of highly integrated semiconductor elements.

Claims

1. A photoacid generator comprising an anion represented by the following chemical formula 1 and a cation represented by the following chemical formula 2: [Chemical formula 1] [Chemical formula 2] In the above formulas 1 and 2, A and Z are the same or different and each independently represents a polar functional group; Y is a linker connecting A and Z and is a divalent organic group; R represents a linear or cyclic aliphatic hydrocarbon group or a monocyclic or polycyclic aromatic hydrocarbon group; EWG is an electron withdrawing group substituted on R; M ＋ is an onium ion or a metal ion.

2. The photoacid generator of claim 1 , wherein A is one of a sulfonate group and a carbonate group.

3. The photoacid generator of claim 1 , wherein A is a sulfonate group.

4. 2. The photoacid generator according to claim 1, wherein Y is any one of alkylene groups having 1 to 10 carbon atoms substituted with at least one atomic group containing F.

5. 2. The photoacid generator according to claim 1, wherein Y is any one of alkylene groups having 2 to 5 carbon atoms and substituted with 2 to 4 F.

6. The Z is a sulfonyloxy group (-SO ３ 2. The photoacid generator according to claim 1, wherein the photoacid generator is any one of a group consisting of a aryl group (--), a symmetric group (--), and a carbonyloxy group (--C(=O)O--).

7. The Z is a sulfonyloxy group (-SO ３ 2. The photoacid generator according to claim 1, wherein

8. The linear or cyclic aliphatic hydrocarbon group is an alkyl group, an alkenyl group, a cycloalkyl group, or a cycloalkenyl group substituted with one or more electron-withdrawing groups (EWG); The alkyl group and the alkenyl group each independently have 1 to 30 carbon atoms and are linear or branched. The cycloalkyl group or the cycloalkenyl group is independently a monocyclic or polycyclic group having 3 to 30 carbon atoms. The photoacid generator according to claim 1 .

9. The monocyclic or polycyclic aromatic hydrocarbon group is a carbon number aryl group substituted with one or more electron withdrawing groups (EWG). The photoacid generator according to claim 1 .

10. 2. The photoacid generator of claim 1, wherein R is any one of a cyclic aliphatic hydrocarbon group and an aromatic hydrocarbon group.

11. 2. The photoacid generator according to claim 1, wherein R is a monocyclic aromatic hydrocarbon having 6 to 30 carbon atoms.

12. The EWG is one or more electron-withdrawing groups selected from the group consisting of halogens; cyano groups; nitro groups; hydroxy groups; carbonyl groups; ester groups; imide groups; amide groups; amino groups; carboxy groups; sulfonic acid groups; sulfonamide groups; phosphine oxide groups; alkoxy groups; alkylcarbonyl groups; alkoxycarbonyl groups; sulfonyl groups; aryloxy groups; alkylthioxy groups; arylthioxy groups; alkylsulfoxy groups; arylsulfoxy groups; silyl groups; boron groups; and cycloalkyl groups. The photoacid generator according to claim 1 .

13. The EWG is at least one electron-withdrawing group selected from the group consisting of a nitro group, a halogen, a fluoroalkyl group, a cyano group, and a sulfonyl group; The photoacid generator according to claim 1 .

14. R is a monocyclic aromatic hydrocarbon; The EWG is at least one selected from the group consisting of a halogen group, a nitro group, a halogen, a fluoroalkyl group, a cyano group, and a sulfonyl group; The photoacid generator according to claim 1 .

15. The photoacid generator according to claim 1 , wherein the photoacid generator is a compound represented by the following formula 3: [Chemical formula 3] In the above formula 3, n is an integer from 1 to 10, R., E.W.G., and M. ＋ is as defined above.

16. 2. The photoacid generator of claim 1, wherein the anion represented by Formula 1 is any one selected from the group consisting of:

17. 2. The photoacid generator of claim 1, wherein the cation represented by the formula 2 is any one selected from the group consisting of:

18. The photoacid generator according to claim 1 ; A base polymer; An acid diffusion inhibitor; and an organic solvent.

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