Onium salt, resist composition, and method for producing device using the same

Abstract

To provide an onium salt for a resist composition having high sensitivity to particle beams or electromagnetic radiation, in particular, electron beams or extreme ultraviolet rays.SOLUTION: The onium salt is represented by general formula (1) or (2) in the figure. The onium salt has at least one fluorine atom or iodine atom bonded as a substituent in its structure.SELECTED DRAWING: None

Description

[Technical Field]

[0001] An embodiment of the present invention relates to an onium salt. Another embodiment of the present invention relates to a resist composition containing the onium salt, and a method for manufacturing a device using the resist composition. [Background technology]

[0002] In recent years, photolithography technology using photoresists has been actively used to manufacture display devices such as liquid crystal displays (LCDs) and organic light-emitting diode (OLED) displays, as well as to form semiconductor devices. For the packaging of the electronic components and products mentioned above, active energy rays such as i-rays with a wavelength of 365 nm, and longer wavelengths such as h-rays (405 nm) and g-rays (436 nm) are widely used.

[0003] As device integration becomes more advanced, there is a growing demand for finer lithography techniques, and there is a trend toward using light or particle beams with very short wavelengths for exposure, such as KrF excimer lasers (wavelength 248 nm), ArF excimer lasers (wavelength 193 nm), extreme ultraviolet rays (EUV, wavelength 13.5 nm), and electron beams (EB). Lithography techniques using these short wavelength lights, particularly EUV or electron beams, enable production with a single patterning, and therefore the need for resist compositions that exhibit high sensitivity to EUV or electron beams, etc., is expected to further increase in the future.

[0004] As exposure light sources become shorter in wavelength, resist compositions are required to have improved lithography properties such as sensitivity to the exposure light source and resolution capable of reproducing fine-dimensional patterns. Chemically amplified resists are known as resist compositions that meet these requirements (Patent Document 1).

[0005] However, conventional chemically amplified resists have low absorption of EUV or electron beams, which reduces the efficiency of secondary electron generation and the decomposition efficiency of the acid generator, making it difficult to simultaneously satisfy the characteristics of sensitivity, resolution, and pattern performance. In particular, it is difficult to overcome the reduced throughput due to low sensitivity caused by the low absorption of EUV or electron beams, and the deterioration of resist pattern collapse and line width roughness (LWR) of the line pattern that occurs as the resolution line width of the resist becomes finer.

[0006] To address the above-mentioned issues, photosensitized chemically amplified resist compositions have been proposed for use in a method in which an acid and a sensitizer are generated by lithography using a first actinic energy ray such as EUV or an electron beam, followed by irradiation with a second actinic energy ray such as visible light or ultraviolet light, with the aim of improving the throughput of EUV or electron beam lithography (Patent Documents 2 and 3 and Non-Patent Document 1). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 9-90637 [Patent Document 2] International Publication No. WO2014 / 129556 [Patent Document 3] Japanese Patent Application Laid-Open No. 2015-172741 [Non-patent literature]

[0008] [Non-Patent Document 1] Proc. of SPIE Vol. 9776 977607 Summary of the Invention [Problem to be solved by the invention]

[0009] However, when the resist reaction is accelerated by the second actinic radiation using a photosensitized chemically amplified resist composition utilizing the photosensitization reaction, a photoinduced electron transfer reaction between a sensitizer (electron donor) and a photoacid generator (electron acceptor) is used, and in some cases, acid may be generated by the electron transfer reaction even in unexposed areas several nm away. This may cause unintended diffusion of generated acid without reacting with an acid diffusion controller, even when the resist composition contains an acid diffusion controller. This may result in pattern degradation such as worsening of LWR. In contrast, when a large amount of acid diffusion controller is added to suppress pattern degradation, the amount of photosensitizer generated in the process of generating a photosensitizer by the action of the acid generated by the first actinic radiation is small, making it difficult for the sensitization reaction to occur, and the amount of photosensitizer generated is small, for example, at 1 J / cm. 2 However, even if a large amount of energy is irradiated, the effect of promoting the resist reaction is small.

[0010] In view of the above circumstances, some aspects of the present invention have an objective to provide an onium salt that exhibits excellent sensitivity and pattern characteristics such as LWR, and a resist composition that contains the onium salt and a polymer that has an acid-reactive unit, or a resist composition that contains a polymer that has a unit having the structure of the onium salt and an acid-reactive unit.

[0011] Another object of the present invention is to provide an onium salt and a resist composition that are optimal for use when exposure to a second actinic energy ray, such as ultraviolet light or visible light, is performed after irradiation with a first actinic energy ray, such as an electron beam or extreme ultraviolet light, and a method for manufacturing a device using the resist composition. [Means for solving the problem]

[0012] As a result of extensive research into solving the above-mentioned problems, the present inventors have found that onium salts having a specific structure do not exhibit significant absorption of second actinic rays such as ultraviolet light or visible light, but are converted into ketone derivatives that exhibit absorption of second actinic rays by undergoing a structural change in the presence of an acid, and have thus completed several aspects of the present invention. More specifically, the present inventors have found that an onium salt having a sulfonium skeleton with one or more fluorine or iodine atoms bonded thereto and an acetal or thioacetal moiety has the following properties. (1) The cation has a fluorine or iodine atom, and thus has a high decomposition efficiency with respect to the first actinic energy ray such as an electron beam or extreme ultraviolet light. (2) The onium salt undergoes a structural change due to the acid generated by decomposition upon irradiation with the first actinic energy ray, and the onium salt itself is able to exhibit high absorption of the second actinic energy ray without the need for a substituent with a large structure. (3) The compound whose structure has been changed by the acid has excellent acid generation efficiency after irradiation with the second activation energy. As described above, the present inventors have discovered that a specific onium salt having a fluorine or iodine atom, a sulfonium skeleton, and an acetal or thioacetal moiety has a higher decomposition efficiency with respect to a first activation energy than conventional onium salts, and that an onium salt derivative that has undergone a structural change from the specific onium salt upon irradiation with a first activation energy ray has a higher decomposition efficiency with respect to a second activation energy, leading to the completion of several aspects of the present invention. Furthermore, the present inventors have discovered that by using a resist composition that contains the above-described onium salt and a polymer that has an acid-reactive unit, or a resist composition that contains the above-described unit having an onium salt structure and a polymer that has an acid-reactive unit, it is possible to achieve high sensitivity and excellent pattern characteristics such as LWR.

[0013] One aspect of the present invention for solving the above-mentioned problems is an onium salt represented by any one selected from the following general formula (1) and the following general formula (2), in which at least one fluorine atom or iodine atom is bonded as a substituent in the structure.

[0014] [ka]

[0015] In the general formula (1), R 1 and R 2 are each independently at least one selected from the group consisting of: optionally substituted linear, branched, or cyclic alkyl groups of 1 to 12 carbon atoms; optionally substituted linear, branched, or cyclic alkenyl groups of 2 to 12 carbon atoms; optionally substituted aryl groups of 6 to 14 carbon atoms; and optionally substituted heteroaryl groups of 4 to 12 carbon atoms. R 1 , R 2 At least two or more of the aryl groups to which the sulfonium group is bonded may form a ring structure together with the sulfur atom to which they are bonded, either directly via a single bond or via at least one group selected from the group consisting of a nitrogen-containing group, an oxygen atom, a sulfur atom, and a methylene group. R 1 and R 2 At least one methylene group therein may be substituted with a divalent heteroatom-containing group.

[0016] R 3 and R 4are each independently at least one selected from the group consisting of an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, an alkylsulfanyl group, an aryl group, a heteroaryl group, an aryloxy group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a (meth)acryloyloxy group, a hydroxy(poly)alkyleneoxy group, an amino group, a cyano group, a nitro group, and a halogen atom, and when having carbon, the number of carbon atoms is 1 to 12, and these optionally have a substituent.

[0017] R 5 and R 6 are each independently at least one selected from the group consisting of: optionally substituted linear, branched or cyclic alkyl groups of 1 to 12 carbon atoms; optionally substituted linear, branched or cyclic alkenyl groups of 1 to 12 carbon atoms; optionally substituted aryl groups of 6 to 14 carbon atoms; and optionally substituted heteroaryl groups of 4 to 12 carbon atoms. R 5 and R 6 are each independently at least one selected from the group consisting of: optionally substituted linear, branched, or cyclic alkyl groups of 1 to 12 carbon atoms; optionally substituted linear, branched, or cyclic alkenyl groups of 2 to 12 carbon atoms; optionally substituted aryl groups of 6 to 14 carbon atoms; and optionally substituted heteroaryl groups of 4 to 12 carbon atoms. R 5 and R 6 may be bonded to each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring structure. R 5 and R 6 At least one methylene group therein may be substituted with a divalent heteroatom-containing group.

[0018] L 1 is at least one selected from the group consisting of a single bond; a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 2 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; a heteroarylene group having 4 to 12 carbon atoms; and a group formed by bonding these groups via a nitrogen-containing group, an oxygen atom, or a sulfur atom. Y 1 and Y 2 is an oxygen atom or a sulfur atom. n1 and n2 are independently an integer of 1 to 3, When n1 is 1, n3 is an integer from 0 to 4, when n1 is 2, n3 is an integer from 0 to 6, when n1 is 3, n3 is an integer from 0 to 8, When n2 is 1, n4 is an integer from 0 to 5; when n2 is 2, n4 is an integer from 0 to 7; when n2 is 3, n4 is an integer from 0 to 9. X - represents a monovalent counter anion.

[0019] In the general formula (2), R 1 ~R 6 , L 1 , Y 1 , Y 2 , n1, n2 and X - is R in the general formula (1). 1 ~R 6 , L 1 , Y 1 , Y 2 , n1, n2 and X - are selected from the same options as each of the above. L 2 is L in the general formula (1). 1 are selected from the same options. When n1 is 1, n3 is an integer from 0 to 3, when n1 is 2, n3 is an integer from 0 to 5, when n1 is 3, n3 is an integer from 0 to 7, When n2 is 1, n4 is an integer from 0 to 4; when n2 is 2, n4 is an integer from 0 to 6; when n2 is 3, n4 is an integer from 0 to 8.

[0020] One embodiment of the present invention for solving the above problems is a resist composition containing the above onium salt and a polymer having an acid-reactive unit.

[0021] Another aspect of the present invention for solving the above problems is a resist composition comprising a polymer having the above onium salt structure as a unit, and a polymer having an acid-reactive unit.

[0022] The onium salt and the polymer having the onium salt structure as a unit, which are embodiments of the present invention, generate an acid upon exposure to light.

[0023] Another aspect of the present invention is a method for manufacturing a device, comprising the steps of applying the composition onto a substrate to form a resist film, irradiating the resist film with a first active energy ray, irradiating the resist film after the irradiation of the first active energy ray with a second active energy ray, and developing the resist film after the irradiation of the second active energy ray to obtain a pattern. [Effects of the Invention]

[0024] According to some aspects of the present invention, there is provided an onium salt that is highly sensitive and exhibits excellent pattern characteristics such as LWR, and is suitable for use as a resist composition for a lithography process that uses a first active energy ray such as a particle beam or electromagnetic wave and a second active energy ray such as ultraviolet light or visible light. The present invention also provides a resist composition that contains the onium salt and is highly sensitive to a first active energy ray such as a particle beam or electromagnetic wave, particularly an electron beam or extreme ultraviolet light, and a device manufacturing method using the same. DETAILED DESCRIPTION OF THE INVENTION

[0025] The present invention will be specifically described below, but the present invention is not limited thereto. <1> Onium salts

[0026] An onium salt according to one embodiment of the present invention is represented by any one selected from the general formulas (1) and (2).

[0027] An onium salt according to one embodiment of the present invention has at least one fluorine or iodine atom bonded to its structure and a specific structure of an acetal moiety, a thioacetal moiety, or the like, and a sulfonium skeleton, and therefore has high decomposition efficiency with respect to a first active energy ray such as a particle beam or an electromagnetic wave, and also has high absorption with respect to irradiation with a second active energy ray after irradiation with the first active energy ray.

[0028] Furthermore, the onium salt according to one embodiment of the present invention does not exhibit significant absorption of the second actinic energy ray, such as ultraviolet light or visible light. Meanwhile, the acid generated by the first actinic energy ray deprotects the acetal or thioacetal moiety of the onium salt, converting it to a ketone derivative without impairing its function as a photoacid generator. Because the conjugation length of the ketone derivative increases, the absorption wavelength easily increases, resulting in absorption of the second actinic energy ray. Since the ketone derivative is generated in the resist film in the exposed area irradiated with the first actinic energy ray, further irradiation with the second actinic energy ray can increase the amount of acid generated in the exposed area irradiated with the first actinic energy ray.

[0029] In the present invention, the second active energy ray is preferably ultraviolet light or visible light having a wavelength of 365 nm or more, and more preferably 420 nm or less.

[0030] In the general formulas (1) and (2), R 1 and R 2 are each independently at least one selected from the group consisting of: optionally substituted linear, branched or cyclic alkyl groups of 1 to 12 carbon atoms; optionally substituted linear, branched or cyclic alkenyl groups of 2 to 12 carbon atoms; optionally substituted aryl groups of 6 to 14 carbon atoms; and optionally substituted heteroaryl groups of 4 to 12 carbon atoms.

[0031] R 1 and R 2Specific examples of the linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms in the formula (I) include alkyl groups such as methyl, ethyl, n-propyl, n-butyl, isopropyl, t-butyl, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, adamantan-1-yl group, adamantan-2-yl group, norbornan-1-yl group, and norbornan-2-yl group.

[0032] R 1 and R 2 In the alkyl group, at least one methylene group may be substituted with a divalent heteroatom-containing group. Examples of the divalent heteroatom-containing group include -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, -N(R 23 )-, -N(Ar)-, -S-, -SO-, and -SO2-. However, the sulfur atom (S + ) is preferably not directly bonded to the heteroatom-containing group but is bonded to a divalent hydrocarbon group. 23 and Ar will be described later. R 1 and R 2 Examples of the alkenyl group include those in which at least one carbon-carbon single bond of the alkyl group is substituted with a carbon-carbon double bond.

[0033] R 1 and R 2 Specific examples of the aryl group having 6 to 14 carbon atoms which may have a substituent include monocyclic aromatic hydrocarbon groups and condensed polycyclic aromatic hydrocarbon groups in which at least two of the monocyclic aromatic hydrocarbons are condensed. These aryl groups may have a substituent. Examples of the monocyclic aromatic hydrocarbon group include groups having a skeleton such as benzene. Examples of the condensed polycyclic aromatic hydrocarbon group include groups having a skeleton such as indene, naphthalene, azulene, anthracene, and phenanthrene.

[0034] R 1 and R 2 Examples of the heteroaryl group having 4 to 12 carbon atoms which may have a substituent include those which contain at least one atom selected from an oxygen atom, a nitrogen atom and a sulfur atom in the skeleton, in place of at least one carbon atom of the aryl group.

[0035] Examples of the heteroaryl group include a monocyclic aromatic heterocyclic group and a fused polycyclic aromatic heterocyclic group in which at least one of the monocyclic aromatic heterocyclic rings is fused with the aromatic hydrocarbon group or aliphatic heterocyclic group, etc. These aromatic heterocyclic groups may have a substituent. Examples of the monocyclic aromatic heterocyclic group include groups having a skeleton such as furan, pyrrole, imidazole, pyran, pyridine, pyrimidine, and pyrazine.

[0036] Examples of the fused polycyclic aromatic heterocyclic group include groups having a skeleton such as indole, purine, quinoline, isoquinoline, chromene, phenoxazine, xanthene, acridine, phenazine, and carbazole.

[0037] R 1 and R 2 The substituent in (hereinafter also referred to as "first substituent") is a hydroxy group, a cyano group, a mercapto group, a carboxy group, an alkyl group (-R 23 ), alkoxy group (-OR 23 ), acyl group (-COR 23 ), alkoxycarbonyl group (-COOR 23 ), aryl group (-Ar), aryloxy group (-OAr), amino group, alkylamino group (-NHR 23 ), dialkylamino group (-N(R 23 )2), arylamino group (-NHAr), diarylamino group (-N(Ar)2), N-alkyl-N-arylamino group (-NR 23 Ar), phosphino group, silyl group, halogen atom, trialkylsilyl group (-Si-(R 23) 3), a silyl group in which at least one alkyl group of the trialkylsilyl group is substituted with Ar, an alkylsulfanyl group (—SR 23 ) and arylsulfanyl group (-SAr), but are not limited to these. The first substituent may also be a polymerizable group such as a (meth)acryloyl group. R 23 and Ar are explained below.

[0038] The R in the first substituent 23 is preferably an alkyl group having 1 or more carbon atoms. It is more preferably one having 20 or fewer carbon atoms. Specific examples of alkyl groups having 1 or more carbon atoms include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, and n-decyl; branched alkyl groups such as isopropyl, isobutyl, tert-butyl, isopentyl, tert-pentyl, and 2-ethylhexyl; alicyclic alkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantan-1-yl, adamantan-2-yl, norbornan-1-yl, and norbornan-2-yl; silyl-substituted alkyl groups in which one of the hydrogen atoms in these groups is substituted with a trialkylsilyl group such as trimethylsilyl, triethylsilyl, and dimethylethylsilyl; and alkyl groups in which at least one of the hydrogen atoms in these groups is substituted with a cyano group, a fluoro group, or the like. The carbon-carbon single bond in the alkyl group may be replaced with a carbon-carbon double bond.

[0039] Ar in the first substituent is preferably an aryl group or a heteroaryl group. A heteroaryl group is an aryl group containing one or more heteroatoms in the ring structure. Specific examples of Ar preferably include those having 20 or less carbon atoms, such as a phenyl group, a biphenyl group, a terphenyl group, a quaterphenyl group, a naphthyl group, an anthryl group, a phenanthrenyl group, a pentalenyl group, an indenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a heptalenyl group, a naphthacenyl group, a pyrenyl group, a chrysenyl group, a tetracenyl group, a furanyl group, a thienyl group, a pyranyl group, a sulfanylpyranyl group, a pyrrolyl group, an imidazoyl group, an oxazolyl group, a thiazolyl group, a pyrazoyl group, a pyridyl group, an isobenzofuranyl group, a benzofuranyl group, an isochromenyl group, a chromenyl group, an indolyl group, an isoindolyl group, a benzimidazoyl group, a xanthenyl group, an acridinyl group, and a carbazoyl group.

[0040] R 1 and R 2 When the alkyl group or the like has the first substituent and the onium salt is a low molecular weight compound, R 1 and R 2 The number of carbon atoms in the first substituent is preferably 1 to 20, including the number of carbon atoms in the first substituent.

[0041] R 1 , R 2 At least two or more of the aryl groups to which the sulfonium group is bonded may form a ring structure together with the sulfur atom to which they are bonded, either directly via a single bond or via at least one group selected from the group consisting of a nitrogen-containing group, an oxygen atom, a sulfur atom, and a methylene group. R 1 and R 2 At least one methylene group therein may be substituted with a divalent heteroatom-containing group.

[0042] Examples of the "nitrogen atom-containing group" include an aminodiyl group (-NH-), an alkylaminodiyl group (-NR 23 Examples of divalent groups containing a nitrogen atom include a divalent group containing a nitrogen atom, such as an arylaminodiyl group (-NAr-) and an arylaminodiyl group (-NAr-).23 and for Ar, R of the first substituent 23 and Ar.

[0043] In one embodiment of the present invention, the onium salt may be a polymer component bonded to a part of a polymer as one unit of the polymer, i.e., the onium salt structure as a unit, or may be a polymer component contained as a unit of a separately added polymer. When the onium salt is a polymer component, the first substituent may be the main chain of the polymer. R 1 and R 2 When the first substituent is in the backbone of the polymer, R 1 and R 2 The number of carbon atoms in the polymer main chain is excluded. When the onium salt in one embodiment of the present invention is a polymer component, it is preferable to adjust the weight average molecular weight of the entire polymer component to 2,000 to 200,000. In the present invention, a low molecular weight compound is one having a weight average molecular weight of less than 2,000, and a polymer component is one having a weight average molecular weight of 2,000 or more.

[0044] R 1 and R 2 As the alkyl group, an aryl group is preferred from the viewpoint of improving stability.

[0045] R 3 and R 4are each independently at least one selected from the group consisting of an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, a heteroarylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a heteroaryloxycarbonyl group, an arylsulfanylcarbonyl group, a heteroarylsulfanylcarbonyl group, an arylsulfanyl group, a heteroarylsulfanyl group, an alkylsulfanyl group, an aryl group, a heteroaryl group, an aryloxy group, a heteroaryloxy group, an alkylsulfinyl group, an arylsulfinyl group, a heteroarylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a heteroarylsulfonyl group, an arylsulfonyl group, a heteroarylsulfonyl group, a (meth)acryloyloxy group, a hydroxy(poly)alkyleneoxy group, an alkylamino group, a dialkylamino group, a cyano group, a nitro group, and a halogen atom.

[0046] R 3 and R 4 The alkyl group in the formula (I) may be linear, branched, or cyclic. Specifically, the alkyl group in the formula (I) may be linear, branched, or cyclic. 23 The alkyl groups of R 3 and R 4 The alkyl group moiety of the alkoxy group, alkylcarbonyl group, alkoxycarbonyl group, etc. in R 1 and R 2 The alkyl groups in the above formula (I) are the same as those in the above formula (I).

[0047] R 3 and R 4 The aryl and heteroaryl groups in 1 and R 2 The aryl and heteroaryl groups are the same as those in R 3 and R 4 The aryl group moiety such as the arylcarbonyl group and the aryloxycarbonyl group in 1 and R 2 The aryl groups in R 3 and R 4The heteroaryl group moiety such as the heteroarylcarbonyl group and heteroaryloxycarbonyl group in R 1 and R 2 The heteroaryl groups in R 3 and R 4 In terms of synthesis, it is preferable that the substituent does not have a heteroaryl group moiety such as the heteroarylcarbonyl group or heteroaryloxycarbonyl group. In the general formulas (1) and (2), R 4 When there are two or more 4 Two of these may be linked to each other to form a ring structure.

[0048] R 3 and R 4 Examples of the hydroxy(poly)alkyleneoxy group in the formula include a polyethyleneoxy group and a polypropyleneoxy group. R 3 and R 4 Examples of the halogen atom in include a fluorine atom, a chlorine atom, and an iodine atom.

[0049] R 3 and R 4 In the alkyl group in the formula (I), at least one methylene group is replaced by the R 1 and R 2 However, it is preferable that the skeleton does not contain consecutive bonds of heteroatoms such as -OO-, -SS-, and -OS-.

[0050] R 3 and R 4 When R has carbon atoms, the number of carbon atoms is preferably 1 to 12, and these may have a substituent (hereinafter also referred to as a "second substituent"). 3 and R 4 The carbon-carbon single bond in the alkyl group may be replaced with a carbon-carbon double bond. R 3 and R 4The second substituent that may be possessed by may be the same as the first substituent.

[0051] R 3 and R 4 has the second substituent and the onium salt is a low molecular weight compound, R 3 and R 4 The number of carbon atoms in R is preferably 1 to 12, including the number of carbon atoms in the second substituent. 3 and R 4 If the second substituent is on the polymer backbone, R 3 and R 4 The number of carbon atoms in the polymer backbone is excluded.

[0052] In one embodiment of the present invention, the onium salt is R 4 It is preferable that the compound has at least one R 4 is preferably a hydroxy group or an alkoxy group. 4 is preferably in the ortho or para position relative to the bonding position of the acetal or thioacetal moiety. 4 When the compound has a hydroxy group or an alkoxy group at the ortho- or para-position as the hydroxyl group, the compound tends to absorb more of the second actinic ray when it becomes a ketone derivative. In particular, a hydroxy group is more preferable because it improves the affinity for an alkaline developer and improves the solubility of the onium salt during development.

[0053] Generally, when the cationic structure of the onium salt is enlarged by adding a substituent to the cation of the onium salt, the hydrophobicity increases, which may cause a dissolution inhibiting effect during development. Therefore, it is preferable that the ketone derivative does not have a hydrophobic substituent, which tends to have a low affinity to alkaline developers, and the absorption wavelength of the ketone derivative after deprotection of the acetal or thioacetal moiety becomes longer, thereby increasing the absorption of the second actinic ray. In addition, a basic substituent is not preferable because it deactivates the generated acid and inhibits the decomposition of the acid-dissociable group. For these reasons, the cation of the onium salt, which is one embodiment of the present invention, is R 3 and R4 It is preferable that R does not have a substituent containing an aromatic ring or an alicyclic structure, and does not have a basic group such as an amino group that reacts with the generated acid, and it is also preferable that the molecular weight of the cation portion of the onium salt is 500 or less. 3 and R 4 It is more preferable that the compound does not have a basic group such as an amino group.

[0054] R 4 If there are multiple 4 At least one of R is preferably a hydroxy group or an alkoxy group, and is located at the ortho or para position relative to the bonding position of the acetal or thioacetal moiety. 4 If there are multiple 4 If at least one of R is a hydroxy group or an alkoxy group, the other R 4 may not be a hydroxy group or an alkoxy group. In order to increase the absorption wavelength of the ketone derivative produced by the acid, two or more R 4 More preferably, R is a substituent that donates an electron to the aromatic ring to which R is bonded. Even more preferably, R is a substituent that donates an electron to the aromatic ring to which R is bonded at two or more positions that are ortho- or para-positions relative to the bonding position of the acetal or thioacetal moiety. 4 It is preferable that the alkyl group has a hydroxy group or an alkoxy group.

[0055] R 5 and R 6 are each independently preferably an optionally substituted linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; an optionally substituted linear, branched or cyclic alkenyl group having 2 to 12 carbon atoms; an optionally substituted aryl group having 6 to 14 carbon atoms; or an optionally substituted heteroaryl group having 4 to 12 carbon atoms, which are the same as those described above for R 1 and R 2 Preferably, each of the above is selected from the same options. R 5 and R 6 Examples of the substituent (hereinafter also referred to as "third substituent") include the same as those for the first substituent.

[0056] R 5 and R 6 may be bonded to each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom and an alkylene group to form a ring structure. R 5 and R 6 At least one methylene group therein may be substituted with a divalent heteroatom-containing group. From a synthetic standpoint, the R 5 and R 6 are preferably the same.

[0057] In the general formulas (1) and (2), L 1 is at least one selected from the group consisting of a single bond; a linear, branched, or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 2 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; a heteroarylene group having 4 to 12 carbon atoms; and a group formed by bonding these groups via a nitrogen-containing group, an oxygen atom, or a sulfur atom. In the general formula (2), L 2 is the above L 1 The same can be mentioned. In the general formulas (1) and (2), Y is an oxygen atom or a sulfur atom.

[0058] In the general formula (1), n1 and n2 are each independently an integer of 1 to 3. When n1 is 1, n3 is an integer from 0 to 4; when n1 is 2, n3 is an integer from 0 to 6; when n1 is 3, n3 is an integer from 0 to 8. When n2 is 1, n4 is an integer from 0 to 5; when n2 is 2, n4 is an integer from 0 to 7; when n2 is 3, n4 is an integer from 0 to 9. In the general formula (2), when n1 is 1, n3 is an integer of 0 to 3; when n1 is 2, n3 is an integer of 0 to 5; and when n1 is 3, n3 is an integer of 0 to 7. When n2 is 1, n4 is an integer from 0 to 4; when n2 is 2, n4 is an integer from 0 to 6; when n2 is 3, n4 is an integer from 0 to 8.

[0059] The onium salt is more preferably an onium salt represented by the following general formula (3) or (4). [ka]

[0060] In the general formulas (3) and (4), R 5 and R 6 has at least one iodine atom as a substituent. R 1 ~R 4 , L 2 , X - , Y 1 , and Y 2 is R in the general formulas (1) and (2). 1 ~R 4 , L 2 , X - , Y 1 and Y 2 are selected from the same options as each of the above. In the general formula (3), n3 is an integer of 0 to 4, and n4 is an integer of 0 to 5. In the general formula (4), n3 is an integer of 0 to 3, and n4 is an integer of 0 to 4.

[0061] In some embodiments of the present invention, the cation of the onium salt can be exemplified by the sulfonium cation shown below. However, some embodiments of the present invention are not limited thereto.

[0062] [ka] [ka] [ka]

[0063] In the general formulas (1) to (4), X - is a monovalent anionic group.

[0064] The monovalent anionic group is not particularly limited, and may be a sulfonate anion (SO - ), carboxylate anion (COO - ), imide anion, methide anion, borate anion, and other monovalent anions.

[0065] Specifically, the following can be mentioned:

[0066] [ka]

[0067] The onium salt according to one embodiment of the present invention may be a polymer containing an acid generator unit in which the anion moiety is bonded to a part of the polymer. Examples of such an onium salt include those represented by the general formulas (1) to (4) above, where X - The polymer may have a unit represented by the following general formula (14): The onium salt is preferably contained in the composition as one unit of the acid generator unit-containing resin, since diffusion of the acid generated upon exposure is suppressed, thereby suppressing LWR. [ka]

[0068] The unit represented by the general formula (14) may be included as unit A, which will be described later.

[0069] In the general formula (14), R 7 is at least one selected from the group consisting of a hydrogen atom, an alkyl group, and a halogenated alkyl group.

[0070] L 6 L is at least one selected from the group consisting of a direct bond, a carbonyloxy group, a carbonylamino group, a linear, branched or cyclic alkylenecarbonyloxy group which may have a substituent, and an alkylenecarbonylamino group. 6 The substituent in the formula (I) may be the same as the first substituent.

[0071] Z 1 is a linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched alkenyl group having 1 to 12 carbon atoms, or a linear or branched aryl group having 6 to 14 carbon atoms. Some or all of the hydrogen atoms in these alkyl, alkenyl, and aryl groups may be substituted with fluorine atoms. At least one methylene group in these groups may be substituted with the divalent heteroatom-containing group.

[0072] Examples of the anion moiety represented by the general formula (14) include the following: However, the present invention is not limited to these.

[0073] [ka]

[0074] [ka]

[0075] The onium salt according to some embodiments of the present invention has a molar absorption coefficient at 365 nm of 1.0×10 5 cm 2 / mol, and preferably less than 1.0 × 10 4 cm 2 More preferably, it is less than 1 / mol.

[0076] In addition, the ketone derivative obtained by deprotecting the acetal or thioacetal of the onium salt according to some embodiments of the present invention has a molar absorption coefficient at 365 nm of 1.0×10 5 cm 2 / mol or more, and 1.0 × 10 6 cm 2 / mol or more is more preferable.

[0077] The molar absorption coefficient at 365 nm of the ketone derivative is preferably 5 times or more, more preferably 10 times or more, and even more preferably 20 times or more, of the molar absorption coefficient at 365 nm of the onium salt according to some embodiments of the present invention. To achieve the above properties, an onium salt represented by the general formula (1) or (2) may be used.

[0078] Without being bound by any particular theory, it is believed that the R 5 and R 6 When R in general formula (3) or (4) has an iodine atom or a fluorine atom, it is irradiated with a first active energy ray such as a particle beam or an electromagnetic wave, or is hydrolyzed by an acid generated by irradiation with the first active energy ray, resulting in the elimination of iodine or fluorine, and the structural change of the sulfonium cation to form a ketone derivative. This is thought to reduce the hydrophobicity of the resist composition containing the onium salt or the polymer containing unit A, improve the solubility in an alkaline developer, and thereby improve the solubility of the resist. 5 and R 6 However, when the onium salt or the polymer containing unit A is an alkyl group or an alkenyl group having two carbon atoms and having one or more iodine atoms as substituents, the iodine compound is eliminated by tetramethylammonium hydroxide contained in the alkaline developer, and the bond to the iodine atom is lost from the onium salt or the polymer containing unit A, even without irradiation with the first actinic energy ray. As a result, the hydrophobicity of the resist composition containing the onium salt or the polymer containing unit A (described below) decreases, and the solubility in the alkaline developer can be improved.

[0079] <2> Resist composition A resist composition according to one embodiment of the present invention comprises: the onium salt; and a polymer having an acid-reactive unit. Furthermore, a resist composition according to another aspect of the present invention comprises: A resist composition comprising a polymer having an onium salt structure as unit A, X ― is covalently bonded to the polymer backbone, The resist composition further comprises the polymer having an acid-reactive unit.

[0080] (onium salts) In one embodiment of the present invention, the content of the onium salt in the resist composition is preferably 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass, and even more preferably 10 to 25 parts by mass, per 100 parts by mass of the resist composition components excluding the onium salt.

[0081] In the present invention, when calculating the content of components, organic solvents are not included in 100 parts by mass of the resist composition components.

[0082] When the onium salt is contained in the resin as a single unit, i.e., when the onium salt is a polymer component, the content of the onium salt is based on the mass excluding the polymer main chain. When the onium salt is a polymer component and is contained as a unit of the same polymer together with at least one unit selected from the group consisting of units represented by general formulas (15a) to (15b) described below (hereinafter also referred to as "unit E") and units represented by general formulas (5a) to (5d) described below (hereinafter also referred to as "unit B"), the unit acting as the onium salt preferably accounts for 0.1 to 40 mol%, more preferably 1 to 30 mol%, and even more preferably 3 to 20 mol%, of all polymer units.

[0083] The resist composition may contain the onium salt either alone or in combination of two or more types, regardless of whether it is a polymer component or a low-molecular-weight component.

[0084] (polymer) The unit having an onium salt structure (hereinafter also referred to as "unit A") is not particularly limited as long as it has an onium salt structure and undergoes polarity conversion upon irradiation of at least a part of the polymer with particle beams or electromagnetic waves, i.e., generates anions and radicals by reduction of the onium salt. Specific examples include those represented by the following general formula (16): In the present invention, the term "polarity conversion" refers to a change in polarity from ionic to nonionic directly or indirectly due to irradiation with particle beams or electromagnetic waves. [ka]

[0085] In the general formula (16), L 5 is at least one selected from the group consisting of a carbonyloxy group, a phenylenediyl group, a naphthalenediyl group, a phenylenediyloxy group, a naphthalenediyloxy group, a phenylenediylcarbonyloxy group, a naphthalenediylcarbonyloxy group, a phenylenediyloxycarbonyl group, and a naphthalenediyloxycarbonyl group.

[0086] L 5 There are no particular limitations on the group consisting of a carbonyloxy group, a carbonylamino group, a phenylenediyl group, a naphthalenediyl group, a phenylenediyloxy group, a naphthalenediyloxy group, a phenylenediylcarbonyloxy group, a naphthalenediylcarbonyloxy group, a phenylenediylcarbonyl group, and a naphthalenediylcarbonyl group. L 5 As the alkyl group, a carbonyloxy group and the like are preferred from the viewpoint of ease of synthesis.

[0087] In the general formula (16), Sp represents at least one of a single bond, an optionally substituted linear, branched, or cyclic alkylene group having 1 to 6 carbon atoms, and an optionally substituted linear, branched, or cyclic alkenylene group having 2 to 6 carbon atoms. At least one methylene group in Sp may be substituted with a divalent heteroatom-containing group.

[0088] Sp is the L 5 and the onium salt structure, and is, for example, at least one of a single bond; an optionally substituted linear, branched, or cyclic alkylene group having 1 to 6 carbon atoms; and an optionally substituted linear, branched, or cyclic alkenylene group having 2 to 6 carbon atoms; and at least one methylene group in Sp may be substituted with a divalent heteroatom-containing group.

[0089] Examples of the linear alkylene group having 1 to 6 carbon atoms for Sp include a methylene group, an ethylene group, an n-propylene group, an n-butylene group, an n-pentylene group, and an n-hexylene group. Examples of the branched alkylene group having 1 to 6 carbon atoms for Sp include an isopropylene group, an isobutylene group, a tert-butylene group, an isopentylene group, a tert-pentylene group, and a 2-ethylhexylene group.

[0090] Examples of the cyclic alkylene group having 1 to 6 carbon atoms for Sp include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, and a cyclohexylene group. At least one methylene group in Sp may be substituted with a divalent heteroatom-containing group. Examples of the divalent heteroatom-containing group include -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, and -N(R Sp )-, -N(Ar Sp )-, -S-, -SO-, and -SO2-. Sp Examples of Ar include linear, branched, or cyclic alkyl groups having 1 to 12 carbon atoms.Sp Examples of the alkylene group include aryl groups having 12 or less carbon atoms, such as a phenyl group and a naphthyl group. The number of carbon atoms of the alkylene group of Sp does not include the number of carbon atoms of a substituent that Sp may have.

[0091] Examples of the substituent that Sp may have include a halogen atom such as a fluorine atom or an iodine atom; a hydroxy group; a linear or cyclic alkyl group having 1 to 12 carbon atoms; and a group in which at least one methylene group of the alkyl group is replaced with -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, -N(R Sp )-, -N(Ar Sp Examples thereof include an alkyl group having one heteroatom-containing group selected from the group consisting of -, -S-, -SO-, and -SO2- in its skeleton; an aryl group; and a heteroaryl group. Examples of the alkyl group as a substituent of Sp and the alkyl group containing a heteroatom-containing group in the skeleton include alkyl groups in which the alkylene group of Sp is monovalent. The aryl group as the substituent of Sp includes the above-mentioned Ar Sp Examples of the heteroaryl group as the substituent of Sp include groups having a skeleton such as furan, thiophene, pyrrole, imidazole, pyran, pyridine, pyrimidine, and pyrazine. Sp may be a direct bond, but is preferably a spacer structure that facilitates molecular movement, in consideration of the fact that units containing the onium salt structure undergo radical rebonding and that units A undergo a crosslinking reaction, etc. Preferred examples include an alkylene group, an alkyleneoxy group, and an alkylenecarbonyloxy group.

[0092] R 21 is at least one selected from the group consisting of a hydrogen atom; a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms; and a linear, branched, or cyclic alkenyl group having 2 to 6 carbon atoms; and R 21 At least one hydrogen atom in the alkyl group and alkenyl group may be substituted with a fluorine atom.

[0093] R 21 Examples of the linear alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. R 21 Examples of the branched alkyl group having 1 to 6 carbon atoms include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a tert-pentyl group, and a 2-ethylhexyl group. R 21 Examples of the cyclic alkyl group having 1 to 6 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.

[0094] R 21 Examples of the linear, branched, or cyclic alkenyl group having 2 to 6 carbon atoms include the linear alkyl group, branched alkyl group, and cyclic alkyl group shown above in which at least one carbon-carbon single bond is substituted with a carbon-carbon double bond. Also, R 21 The alkyl group and alkenyl group may be fluorinated alkyl groups and fluorinated alkenyl groups in which at least one hydrogen atom in the alkyl group and alkenyl group is substituted with a fluorine atom. All hydrogen atoms may be substituted with fluorine atoms. As the fluorinated alkyl group, a trifluoromethyl group or the like is preferred.

[0095] In the general formula (16), M + is the sulfonium cation of the onium salt, and X - is a structure containing a monovalent anion with a bond to Sp.

[0096] X -Examples of the anion include at least one selected from the group consisting of alkylsulfonate anion, arylsulfonate anion, alkylcarboxylate anion, arylcarboxylate anion, tetrafluoroborate anion, hexafluorophosphate anion, dialkylsulfonylimide anion, trialkylsulfonate methide anion, tetrakisphenylborate anion, and hexafluoroantimonate anion. - At least one hydrogen atom of the alkyl group and aryl group in the alkyl group may be substituted with a fluorine atom.

[0097] The polymer containing an anionic structure is preferably highly hydrophilic in order to improve contrast in photoresist pattern formation, and specific examples thereof include alkylsulfonate anions, arylsulfonate anions, alkylcarboxylate anions, and arylcarboxylate anions.

[0098] Examples of the acid-reactive unit are units represented by the following general formulas (5a) to (5d) (hereinafter also referred to as "unit B").

[0099] The unit B is a unit having a protecting group that can be deprotected by an acid, and the deprotection of the protecting group by an acid generates a polar group, thereby changing the solubility in a developer. For example, in the case of aqueous development using an alkaline developer, the unit is insoluble in the alkaline developer, but becomes soluble in the alkaline developer when the protecting group in the exposed area is deprotected from the acid-reactive unit by the acid generated from the onium salt upon exposure.

[0100] In the present invention, the developer is not limited to an alkaline developer, and may be an aqueous neutral developer or an organic solvent developer. Therefore, when an organic solvent developer is used, the compound having a protecting group that can be deprotected by an acid is a compound in which the protecting group is deprotected from the compound in the exposed area by the acid generated from the onium salt upon exposure, thereby generating a polar group, and the solubility of the compound in the organic solvent developer is reduced.

[0101] Examples of the polar group include a hydroxy group, a carboxy group, an amino group, and a sulfo group. Among these, a polar group having a hydroxy group in its structure is preferred, and a hydroxy group or a carboxy group is more preferred.

[0102] Specific examples of the protecting group that can be deprotected with an acid include a group that forms a tertiary alkyl ester group with a carboxy group, an alkoxyacetal group, a tetrahydropyranyl group, a siloxy group, and a benzyloxy group. As a compound having such a protecting group, a compound having a styrene skeleton, a methacrylate or an acrylate skeleton and having such a protecting group on the side chain is preferably used.

[0103] The structure of the unit B may be at least one of the units represented by the following (5a) to (5d). [ka]

[0104] In the general formulas (5a) to (5d), R 7 is R in the general formula (14) 7 are selected from the same options.

[0105] R 7 Examples of the alkyl group include methyl, ethyl, n-propyl, n-butyl, isopropyl, t-butyl, cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups, some of whose hydrogen atoms may be substituted with halogen. Among these, hydrogen atoms, methyl, and trifluoromethyl groups are particularly preferred.

[0106] In the general formulas (5a) to (5d), L 3 is at least one selected from the group consisting of a direct bond, a carbonyloxy group, a carbonylamino group, a linear, branched or cyclic alkylenecarbonyloxy group which may have a substituent, and an alkylenecarbonylamino group.

[0107] In the general formulas (5a) to (5d), the moiety represented by the following formula (a-1) or (a-2) is a protecting group that is deprotected by an acid (hereinafter also referred to as an "acid labile group"), and is decomposed by the action of an acid to generate a carboxylic acid or a phenolic hydroxyl group, thereby changing the solubility in a developer.

[0108] The dashed lines in the following general formulae (a-1) and (a-2) represent L in the general formulae (5a) to (5d). 3 or a bond to an oxygen atom. R in the following formulas (a-1) and (a-2) 8 ~R 13 is R in the general formulas (5a) to (5d). 8 ~R 13 Preferably, it is selected from the same options.

[0109] [ka]

[0110] In the general formula (a-1), R 8 and R 9 are each independently a straight-chain, branched, or cyclic alkyl group, and examples thereof include alkyl groups having 1 to 12 carbon atoms, such as methyl, ethyl, n-propyl, n-butyl, isopropyl, t-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantan-1-yl, adamantan-2-yl, norbornan-1-yl, and norbornan-2-yl groups.

[0111] R 10 is a linear, branched, or cyclic alkyl group which may have a substituent, and the alkyl group is R 8The alkyl groups R are selected from the same groups as those R , and some of the hydrogen atoms may be substituted with hydroxyl groups, alkoxy groups, oxo groups, amino groups, alkylamino groups, etc. 8 , R 9 , and R 10 may form a ring structure directly via a single bond or via at least one methylene group. R 8 ~R 10 Examples of the substituent (also referred to as the "fourth substituent") that may be possessed by include the same as those for the first substituent.

[0112] In the general formula (a-2), R 11 and R 12 are each independently a hydrogen atom and a linear or cyclic alkyl group, and the alkyl group is R 8 is selected from the same options as each of the alkyl groups in

[0113] R 13 is a linear, branched, or cyclic alkyl group which may have a substituent (also referred to as a "fifth substituent"); R 8 The R alkyl group is selected from the same options as the R alkyl group, and some of the hydrogen atoms may be substituted with a fifth substituent such as a hydroxyl group, an alkoxy group, an oxo group, an amino group, or an alkylamino group. 11 , R 12 and R 13 may form a ring structure directly via a single bond or via at least one methylene group.

[0114] Specific examples of the general formulae (a-1) and (a-2) include the structures shown below: However, the present invention is not limited to these.

[0115] [ka]

[0116] R in the general formulae (5c) to (5d) 14is at least one selected from the group consisting of an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an alkylsulfanyl group, an alkylsulfinyl group, an alkylsulfonyl group, an amino group, a cyano group, a nitro group, and a halogen atom. 3 are selected from the same options as each of the above.

[0117] L in the general formulae (5a) to (5d) 3 represents a direct bond, a carbonyloxy group, a carbonylamino group, or an optionally substituted linear, branched or cyclic alkylenecarbonyloxy or alkylenecarbonylamino group, and the carbonyloxy group or carbonylamino group is bonded to the acid labile group.

[0118] In the general formulas (5c) to (5d), n5 is an integer of 1 to 2; n6 is an integer of 0 to 4 when n5 is 1, and an integer of 0 to 6 when n5 is 2; n7 is an integer of 1 to 5 when n5 is 1, and an integer of 1 to 7 when n5 is 2; and n6+n7 is an integer of 1 to 5 when n5 is 1, and an integer of 1 to 7 when n5 is 2.

[0119] Specific examples of the unit B represented by the general formulae (5a) to (5d) include the following: However, the present invention is not limited to these.

[0120] [ka]

[0121] In place of or in addition to the unit B, the composition may contain a compound having a polymerizable group that polymerizes with an acid and / or a crosslinking agent that crosslinks with an acid. The compound having a polymerizable group that polymerizes with an acid is a compound that changes its solubility in a developer by polymerizing with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and reduces the solubility of the compound in the aqueous developer after polymerization. Specific examples include compounds having an epoxy group, a vinyloxy group, an oxetanyl group, etc.

[0122] The compound having a polymerizable group that is polymerizable by an acid may be a polymerizable low molecular weight compound or a polymer component containing a unit having a polymerizable group.

[0123] A crosslinking agent capable of crosslinking with an acid is a compound that changes its solubility in a developer by crosslinking with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and reduces the solubility of the compound in the aqueous developer after polymerization or crosslinking. Specific examples include crosslinking agents having crosslinkable groups such as epoxy groups, vinyloxy groups, 1-alkoxyamino groups, and oxetanyl groups. When the compound is a crosslinking agent with a crosslinking function, examples of the compound that crosslinks, i.e., the compound that reacts with the crosslinking agent to change its solubility in a developer, include compounds having a phenolic hydroxyl group.

[0124] The compound capable of crosslinking with an acid may be a crosslinkable low molecular weight compound or a polymer component containing a unit having a crosslinkable group.

[0125] The unit B may contain, in addition to at least one of the structures represented by general formulas (5a) to (5d), other units commonly used in resist compositions in the polymer component. Examples of such other units include a unit having at least one skeleton selected from the group consisting of a lactone skeleton, a sultone skeleton, a sulfolane skeleton, and a lactam skeleton; a unit having at least one structure selected from the group consisting of an ether structure, an ester structure, an acetal structure, and a structure having a hydroxy group; a hydroxyaryl group-containing unit; and the like.

[0126] The unit B may be contained in the composition as a homopolymer containing the unit B, or as a copolymer having the unit B and at least one unit E selected from the group consisting of general formulas (15a) to (15b) described below. When the unit B is a copolymer, the unit B preferably accounts for 3 to 50 mol %, more preferably 5 to 35 mol %, and even more preferably 7 to 30 mol % of all units in the polymer.

[0127] Another example of the acid-reactive unit is a unit (hereinafter also referred to as "unit C") in which at least one compound represented by the following general formula (5e) or (5f) is bonded to the * portion of the following general formula (6) at any position of the compound, and the unit C is contained in the polymer. When the polymer contains the unit C, it becomes possible to improve sensitivity to particle beams or electromagnetic waves.

[0128] [ka]

[0129] In the general formula (5e), ​​R 15 and R 16 R is independently at least one selected from the group consisting of a hydrogen atom, an electron-donating group, and an electron-withdrawing group. 15 and R 16 At least one of the groups is preferably an electron-donating group, since this improves the acid reactivity. R 17 is at least one selected from the group consisting of a hydrogen atom and an alkyl group which may have a substituent. L 4 is preferably at least one selected from the group consisting of a direct bond; an oxygen atom; a sulfur atom; and a methylene group.

[0130] n8 is an integer of 0 or 1. n9 and n10 are each an integer of 1 to 2, and n9+n10 is 2 to 4. When n9 is 1, n11 is an integer from 0 to 4. When n9 is 2, n11 is an integer from 0 to 6. When n10 is 1, n12 is an integer from 0 to 4. When n10 is 2, n12 is an integer from 0 to 6. n11 is 2 or more and R 15 is an electron donating group or an electron withdrawing group, two R 15 may form a ring structure with each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group. n12 is 2 or more and R 16 is an electron donating group or an electron withdrawing group, two R 16 may form a ring structure with each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group.

[0131] In the general formula (5f), R 18 are each independently at least one selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group. R 18 At least one of the groups is the electron-donating group. R 19 is at least one selected from the group consisting of a hydrogen atom; an alkyl group which may have a substituent; and an alkenyl group which may have a substituent; and 18 At least one methylene group therein may be substituted with a divalent heteroatom-containing group.

[0132] R 19 Examples of the substituent that may be contained in Sp include the same substituents as those contained in Sp.

[0133] R 20 is R in the general formula (5e) 17 are selected from the same options.

[0134] n14 is an integer from 0 to 7, n13 is 1 or 2, and when n13 is 1, n14 is an integer of 0 to 5, and when n13 is 2, n14 is an integer of 0 to 7.

[0135] n14 is 2 or more and R 18 is an electron donating group or an electron withdrawing group, two R 18 may form a ring structure with each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group.

[0136] n14 is 2 or more and R 18 is an electron donating group or an electron withdrawing group, two R 18 may form a ring structure with each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group. [ka]

[0137] In the general formula (6), R 21 , L 5 and Sp are the same as in the general formula (16).

[0138] R 15 , R 16 and R 18 The electron donating group in 22 ), the alkyl group (-R 22 an alkenyl group in which at least one carbon-carbon single bond of the above group is replaced by a carbon-carbon double bond; and an alkoxy group (-OR) bonded to the ortho or para position of the aromatic ring relative to the hydroxyl group. 22 ) and alkylthio groups (-SR 22 ); etc.

[0139] R 22Specific preferred examples of the alkyl group include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, and n-decyl; branched alkyl groups such as isopropyl, isobutyl, tert-butyl, isopentyl, tert-pentyl, and 2-ethylhexyl; alicyclic alkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantan-1-yl, adamantan-2-yl, norbornan-1-yl, and norbornan-2-yl; silyl-substituted alkyl groups in which one of the hydrogen atoms of these alkyl groups is substituted with a trialkylsilyl group such as a trimethylsilyl group, a triethylsilyl group, and a dimethylethylsilyl group; and alkyl groups in which at least one hydrogen atom of a carbon atom that is not directly bonded to the aromatic ring of general formula (5e) or (5f) is substituted with a cyano group, a fluoro group, or the like.

[0140] R 15 , R 16 and R 18 As the electron-withdrawing group of -C(=O)R 22a (R 22a represents a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; —C(═O)R 22b (R 22b is an aryl group having 6 to 14 carbon atoms which may have a substituent; —C(═O)OR 22a ;-SO2R 22a ;-SO2R 22b ; Nitro group; Nitroso group, trifluoromethyl group, -OR substituted in the meta position relative to the hydroxyl group 22a -OR substituted at the meta position relative to the hydroxyl group 22b ; -SR substituted at the meta position relative to the hydroxyl group 22a ; -SR substituted at the meta position relative to the hydroxyl group 22b and the -C(=O)R 22a , -C(=O)OR 22a , -SO2R 22a and -SR 22aa group in which at least one carbon-carbon single bond is replaced with a carbon-carbon double bond or a group in which at least one carbon-carbon single bond is replaced with a carbon-carbon triple bond; and the like. R 22a and R 22b Examples of the substituent that may be possessed by include the same as the substituent that may be possessed by the aforementioned Sp.

[0141] Specific examples of unit C containing the structure of the compound represented by general formula (5e) or (5f) include those shown below.

[0142] [ka]

[0143] In one embodiment of the polymer of the present invention, at least one compound represented by the general formula (5e) or (5f) is contained in the polymer as unit C bonded to the * portion of the general formula (6) at at least one position of the compound. In this case, the position of bonding to the * portion of the general formula (6) is R 15 , R 16 and R 18 For example, in the case of the unit represented by the general formula (6), R 15 It is preferable that one of the H's is replaced with a bond bonded to the * portion of the general formula (6).

[0144] In one embodiment of the present invention, the polymer preferably further contains, in addition to the units A to C, an organometallic compound-containing unit having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi, and Te (hereinafter also referred to as "unit D"). The metal atom contained in the unit is not particularly limited as long as it has high absorption of EUV or electron beams, and may be an atom of Groups 10 to 16 of the periodic table in addition to the above metal atoms. The unit D is preferably a unit in which an alkyl and aryl stannane, alkyl and aryl stibine, alkyl and aryl germane, or alkyl and aryl bismuthine structure is bonded to the * portion of the general formula (6) at at least one position of the structure. The unit D has a high efficiency of generating secondary electrons when irradiated with EUV or an electron beam, and can increase the decomposition efficiency of the onium salt or the units A to C. The unit D is not particularly limited as long as it contains the metal atom that has a high absorption rate for EUV or an electron beam, and specific examples thereof include the units shown below.

[0145] [ka]

[0146] In the general formula, R 24a Each of R is preferably independently at least one selected from the group consisting of a hydrogen atom and an alkyl group. 24a The alkyl group may have a substituent. Examples of the alkyl group include linear or branched alkyl groups having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, an n-isopropyl group, a sec-butyl group, a tert-butyl group, an n-butyl group, and a pentyl group. Examples of the substituent that the alkyl group may have include a hydroxy group, a sulfonyloxy group, an alkylcarbonyloxy group, an alkyloxycarbonyl group, a cyano group, a methoxy group, and an ethoxy group. In the general formula, two or more R 24a is not a hydrogen atom, 24a Two R are not hydrogen atoms 24a may form a ring structure directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group. In the general formula, two R 24bmay form a ring structure directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group. n15 is 4.

[0147] In the general formula, R 24b is at least one selected from the group consisting of an optionally substituted linear, branched or cyclic alkyl group of 1 to 6 carbon atoms; an optionally substituted linear, branched or cyclic alkenyl group of 1 to 6 carbon atoms; an optionally substituted aryl group of 6 to 14 carbon atoms; an optionally substituted heteroaryl group of 4 to 12 carbon atoms; and a direct bond. R 24b Examples of the linear, branched or cyclic alkyl group of include the same as the alkyl group of Sp. R 24b Examples of the linear, branched or cyclic alkenyl group of include the same alkenyl groups as those of Sp.

[0148] R 24b Examples of the aryl group having 6 to 14 carbon atoms for R include the same as the aryl group for Sp. 24b Examples of the heteroaryl group having 4 to 12 carbon atoms include the same heteroaryl groups as those described above for Sp. Two or more R's 24a may form a ring structure directly through a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom, and a methylene group. 24b At least two of the following may be bonded to each other to form a ring structure together with the metal atom to which they are bonded. R 24a and R 24b Examples of the substituent that may be possessed by include the same as the substituent that may be possessed by the aforementioned Sp.

[0149] Specific examples of unit D include units composed of monomers such as 4-vinylphenyl-triphenylstannane, 4-vinylphenyl-tributylstannane, 4-isopropenylphenyl-triphenylstannane, 4-isopropenylphenyl-trimethylstannane, trimethylstannyl acrylate, tributylstannyl acrylate, triphenylstannyl acrylate, trimethylstannyl methacrylate, tributylstannyl methacrylate, triphenylstannyl methacrylate, 4-vinylphenyl-diphenylstibine, 4-isopropenylphenyl-diphenylstibine, 4-vinylphenyl-triphenylgermane, 4-vinylphenyl-tributylgermane, 4-isopropenylphenyl-triphenylgermane, and 4-isopropenylphenyl-trimethylgermane. When the polymer contains the unit D, it becomes possible to improve the efficiency of generating secondary electrons when irradiated with particle beams or electromagnetic waves.

[0150] (polar polymer) In one embodiment of the present invention, the resist composition preferably contains a polar polymer that includes one or more units represented by the following formulas (15a) to (15b) (hereinafter also referred to as unit E).

[0151] [ka]

[0152] In the general formulas (15a) and (15b), R 7 , R 8 and L 3 are independently R in the formulas (5a) to (5d). 7 , R 8 and L 3 are selected from the same options as each of the above. R 25 is a cyclic group containing at least one selected from the group consisting of -C(O)-O-, -SO2- and -O-SO2-. p is an integer of 0 to 4, and q is an integer of 1 to 5. Examples of the cyclic group include groups containing a lactone skeleton, a sultone skeleton, or a sulfolane skeleton.

[0153] The unit E represented by the general formulae (15a) to (15b) may be contained in a copolymer containing the unit A and / or at least one of the units represented by the formulae (5a) to (5d) as unit B, or may be a unit of another polymer. The unit represented by the general formula (15a) is a hydroxyaryl group-containing unit (hereinafter also referred to as "unit E1"), and the unit represented by the general formula (15b) is a lactone skeleton-, sultone skeleton-, or sulfolane skeleton-containing unit (hereinafter also referred to as "unit E2").

[0154] When a polymer having a hydroxyaryl group-containing unit E1 is used, it can serve as a hydrogen source when the onium salt or the unit A decomposes, thereby further improving the acid generation efficiency and providing high sensitivity, which is preferable. Furthermore, since the polymer having the hydroxyaryl group-containing unit E1 has a low ionization potential, when an electron beam or extreme ultraviolet (EUV) is used as the first active energy ray described below, it is likely to generate secondary electrons, improving the acid generation efficiency of the onium salt or the unit A and providing high sensitivity, which is preferable.

[0155] Examples of the hydroxyaryl group-containing unit E1 include the following: However, the present invention is not limited to these.

[0156] [ka]

[0157] When the hydroxyaryl group-containing unit E1 is contained as a unit of the same polymer together with at least one selected from the group consisting of unit A and unit B, the hydroxyaryl group-containing unit E1 preferably accounts for 3 to 90 mol %, more preferably 5 to 80 mol %, and even more preferably 7 to 70 mol % of all polymer units in a positive resist composition for aqueous development.When used in a negative resist composition for aqueous development, the hydroxyaryl group-containing unit E1 preferably accounts for 60 to 99 mol %, more preferably 70 to 98 mol %, and even more preferably 75 to 98 mol % of all polymer units.

[0158] Examples of the lactone skeleton-, sultone skeleton-, or sulfolane skeleton-containing unit E2 are shown below, but the present invention is not limited thereto.

[0159] [ka]

[0160] When a sultone skeleton-containing unit or a sulfolane skeleton-containing unit is used as unit E2, it generates an acid by ionization when irradiated with an electron beam or extreme ultraviolet (EUV) as the first actinic energy ray, and therefore contributes to the deprotection reaction of the acetal of the onium salt in some embodiments of the present invention, thereby producing a larger amount of a ketone derivative that absorbs the second actinic energy ray. Furthermore, it also contributes to polarity conversion by reaction with the polar polymer containing unit B, thereby further changing the solubility of the resin in the developer, thereby resulting in high sensitivity, which is preferable.

[0161] When a lactone skeleton-containing unit, a sultone skeleton-containing unit, or a sulfolane skeleton-containing unit is contained as unit E2 in the same polymer together with at least one selected from the group consisting of unit A and unit B, the unit E2 preferably accounts for 3 to 70 mol %, more preferably 5 to 50 mol %, and even more preferably 7 to 40 mol % of all units in the polymer.

[0162] In the composition according to one embodiment of the present invention, the polar polymer may contain other compounds as units of the same polymer in addition to the units A to D. The other compounds are not particularly limited as long as they are compounds commonly used in resin compositions for ArF lithography, KrF lithography, electron beam lithography, EUV lithography, and the like.

[0163] (Low molecular weight compounds or polymers containing sulfones or sulfonic acid esters) The composition according to one embodiment of the present invention may contain a low molecular weight compound containing a sulfone or sulfonic acid ester, or a polymer.

[0164] The sulfone or sulfonate ester is not particularly limited, but is preferably one having a linear, branched, or cyclic alkyl or aryl group. More preferably, some or all of the hydrogen atoms in the alkyl or aryl group are substituted with fluorine atoms. The inclusion of such a compound generates an acid upon ionization by irradiation with an electron beam or extreme ultraviolet light, thereby increasing the sensitivity of the resist. The content of the compound containing sulfone or sulfonic acid ester is preferably 0.1 to 50 parts by mass per 100 parts by mass of the resist composition components excluding the total amount of the photoacid generator.

[0165] Specific examples of the compound containing sulfone or sulfonate ester include dimethyl sulfone, isopropyl methyl sulfone, methyl phenyl sulfone, diphenyl sulfone, phenyl trifluoromethyl sulfone, bis(4-fluorophenyl)sulfone, bis(phenylsulfonyl)methane, methyl methanesulfonate, isopropyl methanesulfonate, ethyl trifluoromethanesulfonate, methyl benzenesulfonate, 1,3-propane sultone, 1-propene 1,3-sultone, 1,4-butane sultone, 1,2-bis(tosyloxy)ethane, 1,8-naphthosultone, and the like. These compounds may be used either alone or in combination of two or more.

[0166] (Other units) In addition to the units A to E, the resist composition according to one embodiment of the present invention may also contain units that are typically used in resist compositions, as long as the effects of the present invention are not impaired. For example, a unit (hereinafter also referred to as "unit F") having a skeleton containing an ether group, a lactone skeleton, an ester group, a hydroxy group, an epoxy group, a glycidyl group, an oxetanyl group, or the like at the * portion of general formula (6) can be mentioned. Further, a unit having a skeleton containing an alcoholic hydroxy group at the position * in the general formula (6) (hereinafter also referred to as "unit G") is exemplified. The unit G is different from the units A to F. The inclusion of the unit G in the polymer is preferred because it tends to increase the rate of intramolecular crosslinking reactions. The unit having a skeleton containing an epoxy group, a glycidyl group, an oxetanyl group, or the like is such that when the acid generated from the unit A is a strong acid, that is, when X - CF3SO3 - In the above cases, cationic polymerization can also occur, which is preferable. Furthermore, the polymer in one embodiment of the present invention may have units composed of styrene, 4-hydroxystyrene, 2-hydroxy-6-vinylnaphthalene, acrylic acid esters, methacrylic acid esters, etc. that do not have the structure of general formula (6).

[0167] The resist composition according to one embodiment of the present invention is characterized in that an intramolecular crosslinking reaction occurs upon irradiation with particle beams or electromagnetic waves. Therefore, when a strong acid is used as the acid generated from the onium salt or a unit having the onium salt structure (X - CF3SO3 -It is preferable that the polymer of the present invention does not contain a unit having an acid-dissociable group as another unit, because if the polymer of the present invention contains a unit having an acid-dissociable group as another unit, the solubility of the polymer in an aqueous developer tends to increase due to the action of the acid generated by decomposition of the unit A.

[0168] In one embodiment of the polymer of the present invention, the molar ratio of the unit B to the onium salt or the unit A is preferably 0 to 4, the unit C is preferably 0 to 1, the unit D is preferably 0 to 0.5, the unit E is preferably 0 to 2, the unit F is preferably 0 to 1, and the unit G is preferably 0 to 4. The polymer according to one embodiment of the present invention can be obtained by using the monomer components constituting the respective units as raw materials and polymerizing them by a conventional method so as to achieve the above blending ratio.

[0169] (Other compounds) Examples of other compounds include general-purpose ionic compounds and non-ionic compounds. General-purpose ionic compounds include sulfonium salts and iodonium salts other than those mentioned above. Examples of non-ionic compounds include N-sulfonyloxyimide compounds, oxime sulfonate compounds, organic halogen compounds, and sulfonyldiazomethane compounds.

[0170] When the other compound is contained, the content thereof is preferably 0.1 to 50 parts by mass per 100 parts by mass of the resist composition components excluding the total amount of the onium salt in one embodiment of the present invention.

[0171] (Other ingredients)

[0172] In addition to the components described above, the composition of one embodiment of the present invention may further contain, as necessary, as optional components, in combination with an acid diffusion controller, a surfactant, an organic carboxylic acid, an organic solvent, a dissolution inhibitor, a stabilizer, a dye, a polymer other than the above, and the like, which are used in ordinary resist compositions.

[0173] The acid diffusion controller controls the diffusion of the acid generated from the onium salt within the resist film, thereby suppressing undesirable chemical reactions in unexposed regions. As a result, the storage stability of the resulting resist composition is further improved, the resolution as a resist is further improved, and changes in the line width of the resist pattern due to variations in the exposure time between exposure and development can be suppressed, resulting in a resist composition with excellent process stability.

[0174] Examples of acid diffusion controllers include compounds having one nitrogen atom, two nitrogen atoms, or three nitrogen atoms in the same molecule, amide group-containing compounds, urea compounds, and nitrogen-containing heterocyclic compounds. Furthermore, photodegradable bases that are photosensitive upon exposure to generate weak acids can also be used as acid diffusion controllers. Examples of photodegradable bases include sulfonium salt compounds that decompose upon exposure to light and lose their ability to control acid diffusion, and iodonium salt compounds that lose their ability to control acid diffusion.

[0175] Specific examples of the acid diffusion controller include compounds described in Japanese Patent No. 3577743, JP-A Nos. 2001-215689, 2001-166476, 2008-102383, 2010-243773, 2011-37835, and 2012-173505.

[0176] The content of the acid diffusion controller is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, and even more preferably 0.05 to 3 parts by mass, per 100 parts by mass of the resist composition components.

[0177] The surfactant is preferably used to improve the coating property. Examples of the surfactant include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters, fluorine-containing surfactants, and organosiloxane polymers.

[0178] The content of the surfactant is preferably from 0.0001 to 2 parts by mass, and more preferably from 0.0005 to 1% by mass, per 100 parts by mass of the resist composition components.

[0179] Examples of the organic carboxylic acid include aliphatic carboxylic acids, alicyclic carboxylic acids, unsaturated aliphatic carboxylic acids, oxycarboxylic acids, alkoxycarboxylic acids, ketocarboxylic acids, benzoic acid derivatives, phthalic acid, terephthalic acid, isophthalic acid, 2-naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, etc. When electron beam exposure is performed in a vacuum, there is a risk that the organic carboxylic acid will volatilize from the surface of the resist film and contaminate the inside of the writing chamber. Therefore, preferred organic carboxylic acids are aromatic organic carboxylic acids, and among these, for example, benzoic acid, 1-hydroxy-2-naphthoic acid, and 2-hydroxy-3-naphthoic acid are suitable.

[0180] The content of the organic carboxylic acid is preferably from 0.01 to 10 parts by mass, more preferably from 0.01 to 5 parts by mass, and even more preferably from 0.01 to 3 parts by mass, per 100 parts by mass of the resist composition components.

[0181] Preferred examples of the organic solvent include ethylene glycol monoethyl ether acetate, cyclohexanone, 2-heptanone, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl β-methoxyisobutyrate, ethyl butyrate, propyl butyrate, methyl isobutyl ketone, ethyl acetate, isoamyl acetate, ethyl lactate, toluene, xylene, cyclohexyl acetate, diacetone alcohol, N-methylpyrrolidone, N,N-dimethylformamide, γ-butyrolactone, N,N-dimethylacetamide, propylene carbonate, and ethylene carbonate. These organic solvents may be used alone or in combination.

[0182] The resist composition components are preferably dissolved in the organic solvent to a solids concentration of 1 to 40% by mass, more preferably 1 to 30% by mass, and even more preferably 3 to 20% by mass. By adjusting the solids concentration within this range, the film thickness described below can be achieved. In the present invention, the solid content concentration refers to the ratio of all components excluding the organic solvent to the resist composition.

[0183] When the resist composition of one embodiment of the present invention contains a polymer, the polymer preferably has a weight-average molecular weight of 2,000 to 200,000, more preferably 2,000 to 50,000, and even more preferably 2,000 to 15,000. From the viewpoint of sensitivity, the polymer preferably has a polydispersity (molecular weight distribution) (Mw / Mn) of 1.0 to 1.7, and more preferably 1.0 to 1.2. The weight-average molecular weight and polydispersity of the polymer are defined as polystyrene-equivalent values ​​measured by GPC.

[0184] The composition of one embodiment of the present invention can be obtained by mixing the components of the composition, and the mixing method is not particularly limited.

[0185] <3> Device manufacturing method

[0186] One aspect of the present invention is a method for manufacturing a device, comprising the steps of forming a resist film by, for example, applying the composition onto a substrate; irradiating the resist film with a first active energy ray; irradiating the resist film after the irradiation with the first active energy ray with a second active energy ray; and developing the resist film after the irradiation with the second active energy ray to obtain a pattern.

[0187] One aspect of the present invention may be a method for manufacturing a substrate having a pattern before obtaining individual chips, comprising the steps of forming a resist film using the composition, irradiating with a first active energy ray, irradiating with a second active energy ray, and forming a pattern.

[0188] One aspect of the present invention may be a method for manufacturing a device, including: forming a coating film on a substrate using the composition; and exposing the coating film to first and second active energy rays to obtain an interlayer insulating film.

[0189] The first and second active energy rays are not particularly limited as long as the onium salt according to some embodiments of the present invention does not significantly absorb the second active energy ray, but it is preferable that the wavelength of the first active energy ray is shorter than that of the second active energy ray, or that the energy of the photon or particle beam is higher. Examples of each active energy ray are shown below, but are not limited thereto as long as the wavelength of the first active energy ray is shorter than that of the second active energy ray, or the energy of the photon or particle beam is higher.

[0190] The first active energy ray is not particularly limited as long as it can generate active species such as acid in the resist film after irradiation of the resist film. Preferred examples include KrF excimer laser light, ArF excimer laser light, electron beams, and extreme ultraviolet (EUV) rays.

[0191] The second active energy ray may be any light capable of activating a ketone derivative produced by deprotection of the acetal or thioacetal moiety of the onium salt according to some embodiments of the present invention with an acid generated in the resist film after irradiation with the first active energy ray, thereby generating an active species such as an acid. For example, this means KrF excimer laser light, ultraviolet light, visible light, etc., and it is particularly preferable to use ultraviolet light in the range of 365 nm (i-line) to 436 nm (g-line).

[0192] In one embodiment of the device manufacturing method of the present invention, it is preferable to include a heating step using a heating wire or a laser between the step of irradiating the first active energy ray and the step of irradiating the second active energy ray. By including this step, the decomposition efficiency of the onium salt can be improved, which can lead to further improvement in sensitivity. The heating step can be performed using a hot plate or the like.

[0193] The substrate is not particularly limited and may be any known substrate, such as a substrate made of a metal such as silicon, silicon nitride, titanium, tantalum, palladium, copper, chromium, or aluminum; a glass substrate; or the like.

[0194] In one embodiment of the present invention, preferred examples of the first active energy ray used for exposure in the photolithography process used to obtain an interlayer insulating film or the like for producing an LSI include ultraviolet light, KrF excimer laser light, ArF excimer laser light, electron beams, and extreme ultraviolet light (EUV).

[0195] The exposure dose of the first active energy ray varies depending on the type and blending ratio of each component in the resist composition, the thickness of the resist film, etc., but is generally 1 J / cm 2 or less than 1000μC / cm 2 It is preferable that:

[0196] In one embodiment of the present invention, the resist film formed from the resist composition preferably has a thickness of 10 to 200 nm. The resist composition is applied to a substrate by a suitable application method such as spin coating, roll coating, flow coating, dip coating, spray coating, or doctor coating, and then prebaked at 60 to 150°C for 1 to 20 minutes, preferably 80 to 120°C for 1 to 10 minutes, to form a resist film. The thickness of this resist film is 5 to 200 nm, and preferably 10 to 100 nm. [Example]

[0197] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples in any way.

[0198] <1> Synthesis of sulfonium salts <Synthesis of sulfonium salt 1> (Synthesis Example 1) Synthesis of 2-(4-methoxybenzoyl)dibenzothiophene Add 5.0 g of aluminum chloride to 50 g of methylene chloride and bring the temperature to 0°C. Add 5 g of dibenzothiophene, then dissolve 4.6 g of 4-methoxybenzoyl chloride in 9.2 g of methylene chloride and add dropwise over 30 minutes. After the dropwise addition, stir at 25°C for 1 hour, add 60 g of purified water, stir for an additional 5 minutes, and then wash twice with 20 g of toluene. The resulting organic layer is distilled off. The resulting residue is purified by recrystallization using 30 g of acetone to obtain 6.1 g of 2-(4-methoxybenzoyl)dibenzothiophene.

[0199] [ka]

[0200] (Synthesis Example 2) Synthesis of 2-(4-methoxybenzoyl)dibenzothiophene-5-oxide 6.0 g of 2-(4-methoxybenzoyl)dibenzothiophene obtained in Synthesis Example 1 above was dissolved in 30 g of formic acid, and 3.5 g of 35% by mass hydrogen peroxide solution was added dropwise to the solution under ice cooling. The mixture was then warmed to room temperature and stirred for 5 hours. After stirring, 80 g of pure water was added dropwise to the reaction solution to precipitate a solid. The precipitated solid was filtered, washed three times with 10 g of pure water, and then dried to obtain crude crystals. The crude crystals were recrystallized using 100 g of acetone and 200 g of ethanol to obtain 4.3 g of 2-(4-methoxybenzoyl)dibenzothiophene-5-oxide.

[0201] [ka]

[0202] (Synthesis Example 3) Synthesis of 2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophene-5-oxide 5.0 g of 2-(4-methoxybenzoyl)dibenzothiophene-5-oxide obtained in Synthesis Example 2 was added to 20 g of methanol, followed by the addition of 5.0 g of trimethyl orthoformate and 20 mg of concentrated sulfuric acid and stirring at 60°C for 3 hours. After stirring, the reaction solution was added to a mixed solution of 60 g of methylene chloride and 10 g of a 3% by mass aqueous solution of sodium bicarbonate and stirred for 10 minutes to recover the organic layer. The resulting organic layer was washed three times with water, and the methylene chloride was then distilled off to obtain 4.6 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophene-5-oxide.

[0203] [ka]

[0204] (Synthesis Example 4) Synthesis of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide To a solution of 4.0 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophene-5-oxide (obtained in Synthesis Example 3), 1.1 g of trimethylsilyl chloride, and 1.8 g of triethylamine dissolved in 15.5 g of methylene chloride, 15 ml of a 1.0 mol / L THF solution of phenylmagnesium bromide was added dropwise at 10°C or below, followed by stirring at 25°C for 1 hour. After stirring, 30 g of a 10% by weight aqueous ammonium chloride solution was added at 5°C or below and stirred for an additional 10 minutes. 40 g of methylene chloride was then added and stirred at 25°C for approximately 2 hours. The mixture was separated and washed three times with water, after which the methylene chloride was distilled off to obtain crude crystals. The crude crystals were purified by silica gel column chromatography (methylene chloride / methanol = 90 / 10 (volume ratio)) to obtain 2.6 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-dibenzothiophenium bromide.

[0205] [ka]

[0206] (Synthesis Example 5) Synthesis of 2-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 1) 5.0 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide obtained in Synthesis Example 4 was added to 20 g of 2-iodoethanol, followed by the addition of 5.0 g of trimethyl orthoformate and 20 mg of concentrated sulfuric acid and stirring at 60°C for 3 hours. After stirring, the reaction solution was added to a mixture of 60 g of methylene chloride and 10 g of 3% by weight aqueous sodium bicarbonate solution and stirred for 10 minutes to recover the organic layer. 6.2 g of potassium nonafluorobutanesulfonate and 20 g of water were added to the resulting organic layer and stirred at room temperature for 2 hours. The recovered organic layer was washed three times with water, and the methylene chloride was then distilled off to obtain 5.5 g of 2-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium nonafluorobutanesulfonate.

[0207] [ka]

[0208] <Synthesis of sulfonium salt 2> (Synthesis Example 6) Synthesis of 2-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-1,1,2-trifluoro-4-methacryloxybutanesulfonate (sulfonium salt 2) The same procedure as in Synthesis Example 5 was carried out except that potassium 4-methacryloxy-1,1,2-trifluorobutanesulfonate was used instead of potassium nonafluorobutanesulfonate, thereby obtaining 2.1 g of 2-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-1,1,2-trifluoro-4-methacryloxybutanesulfonate (sulfonium salt 2).

[0209] [ka]

[0210] <Synthesis of sulfonium salt 3> (Synthesis Example 7) Synthesis of 2-[methoxy-(4-methoxyphenyl)-(2,2,2-trifluoroethoxy)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 3) By carrying out the same procedure as in Synthesis Example 5, except that 2,2,2-trifluoroethanol was used instead of 2-iodoethanol, 2.1 g of 2-[methoxy-(4-methoxyphenyl)-(2,2,2-trifluoroethoxy)methyl]-5-phenyl-dibenzothiophenium-nonafluorobutanesulfonate was obtained.

[0211] [ka]

[0212] <Synthesis of sulfonium salt 4> (Synthesis Example 8) Synthesis of 2-[(2-iodopropylenedioxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 4) The same procedure as in Synthesis Example 5 was carried out except that 2-iodopropane-1,2-diol was used instead of 2-iodoethanol, thereby obtaining 1.8 g of 2-[(2-iodopropylenedioxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 4).

[0213] [ka]

[0214] <Synthesis of sulfonium salt 5> (Synthesis Example 9) Synthesis of 2-[(2-fluoropropylenedioxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 5) The same procedure as in Synthesis Example 5 was carried out except that 2-fluoropropane-1,2-diol was used instead of 2-iodoethanol, to obtain 1.6 g of 2-[(2-fluoropropylenedioxy)-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 5).

[0215] [ka]

[0216] <Synthesis of sulfonium salt 6> (Synthesis Example 10) Synthesis of 5-(4-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide 4.0 g of 2-(4-methoxybenzoyl)dibenzothiophene-5-oxide obtained in Synthesis Example 2 and 2.8 g of iodobenzene were dissolved in 16 g of methanesulfonic acid and the temperature was adjusted to 25°C. 1.5 g of diphosphorus pentoxide was added and the mixture was stirred at room temperature for 15 hours. 60 g of purified water was then added and the mixture was stirred for an additional 5 minutes, followed by washing twice with 20 g of ethyl acetate. The mixture was separated, and 3.6 g of potassium bromide and 30 g of methylene chloride were added to the resulting aqueous layer and stirred at room temperature for 2 hours. The mixture was then separated, and the resulting organic layer was washed four times with 40 g of purified water. The recovered organic layer was concentrated and added dropwise to 100 g of diisopropyl ether to precipitate a solid. The precipitated solid was filtered and dried to obtain 6.6 g of 5-(4-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide.

[0217] [ka]

[0218] (Synthesis Example 11) Synthesis of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-(4-iodophenyl)dibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 6) By carrying out the same procedure as in Synthesis Example 5, except that methanol was used instead of 2-iodoethanol, 1.8 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-(iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 6) was obtained.

[0219] [ka]

[0220] <Synthesis of sulfonium salt 7> (Synthesis Example 12) Synthesis of 2-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]-5-(4-iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 7) The same procedure as in Synthesis Example 5 was carried out except that 5-(4-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyl-dibenzothiophenium bromide, to obtain 2.4 g of 2-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]-5-(4-iodophenyl)dibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 7).

[0221] [ka]

[0222] <Synthesis of sulfonium salt 8> (Synthesis Example 13) Synthesis of 5-(3,5-difluorophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide The same procedure as in Synthesis Example 10 was carried out except that 1,3-difluorobenzene was used instead of iodobenzene, to obtain 2.1 g of 5-(3,5-difluorophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide.

[0223] [ka]

[0224] (Synthesis Example 14) Synthesis of 5-(3,5-difluorophenyl)-2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 8) By carrying out the same procedure as in Synthesis Example 5, except for using methanol instead of 2-iodoethanol, 1.6 g of 5-(3,5-difluorophenyl)-2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 8) was obtained.

[0225] [ka]

[0226] <Synthesis of sulfonium salt 9> (Synthesis Example 15) Synthesis of 2-(4-hydroxybenzoyl)-5-phenyldibenzothiophenium bromide 3.0 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide obtained in Synthesis Example 4 was added to 30 ml of acetic acid and heated to 110°C. 2.2 g of 48% aqueous hydrobromic acid was then added dropwise and stirred for 18 hours. After cooling to 25°C, 60 ml of purified water and 40 g of methylene chloride were added and stirred. The mixture was separated and washed three times with water, after which the methylene chloride was distilled off to obtain crude crystals. The crude crystals were purified by silica gel column chromatography (methylene chloride / methanol = 80 / 20 (volume ratio)) to obtain 1.4 g of 2-(4-hydroxybenzoyl)-5-phenyldibenzothiophenium bromide.

[0227] [ka]

[0228] (Synthesis Example 16) Synthesis of 2-[4-hydroxyphenyl-bis(2-iodoethoxy)methyl]-5-phenyldibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 9) The same procedure as in Synthesis Example 5 was carried out except that 2-(4-hydroxybenzoyl)-5-phenyldibenzothiophenium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide, to obtain 2.0 g of 2-[4-hydroxyphenyl-bis(2-iodoethoxy)methyl]-5-phenyldibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 9). [ka]

[0229] <Synthesis of sulfonium salt 10> (Synthesis Example 17) Synthesis of 2-(4-hydroxybenzoyl)-5-(4-iodophenyl)dibenzothiophenium bromide The same procedure as in Synthesis Example 15 was carried out except that 5-(4-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide, to obtain 1.7 g of 2-(4-hydroxybenzoyl)-5-(4-iodophenyl)dibenzothiophenium bromide.

[0230] [ka]

[0231] (Synthesis Example 18) Synthesis of 2-[(4-hydroxyphenyl)-dimethoxymethyl]-5-(4-iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 10) The same procedure as in Synthesis Example 5 was carried out except that methanol was used instead of 2-iodoethanol, to obtain 2.1 g of 2-[(4-hydroxyphenyl)-dimethoxymethyl]-5-(4-iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 10).

[0232] [ka]

[0233] <Synthesis of sulfonium salt 11> (Synthesis Example 19) Synthesis of 2-[4-hydroxyphenyl-bis(2-iodoethoxy)methyl]-5-(4-iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 11) The same procedure as in Synthesis Example 5 was carried out except that 5-(4-iodophenyl)-2-(4-hydroxybenzoyl)dibenzothiophenium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyl-dibenzothiophenium bromide, to obtain 1.8 g of 2-[4-hydroxyphenyl-bis(2-iodoethoxy)methyl]-5-(4-iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 11).

[0234] [ka]

[0235] <Synthesis of sulfonium salt 12> (Synthesis Example 20) Synthesis of 5-(4-hydroxy-3-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide The same procedure as in Synthesis Example 10 was carried out except that 2-iodophenol was used instead of iodobenzene, to obtain 2.4 g of 5-(4-hydroxy-3-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide.

[0236] [ka]

[0237] (Synthesis Example 21) Synthesis of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-(4-hydroxy-2-iodophenyl)dibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 12) By carrying out the same procedure as in Synthesis Example 5, except for using methanol instead of 2-iodoethanol, 2.1 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-(4-hydroxy-2-iodophenyl)dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 12) was obtained.

[0238] [ka]

[0239] <Synthesis of sulfonium salt 13> (Synthesis Example 22) Synthesis of 2-(4-hydroxybenzoyl)-5-(4-hydroxy-3-iodophenyl)dibenzothiophenium bromide The same procedure as in Synthesis Example 15 is carried out except that 5-(4-hydroxy-3-iodophenyl)-2-(4-methoxybenzoyl)dibenzothiophenium bromide is used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide, to obtain 1.2 g of 2-(4-hydroxybenzoyl)-5-(4-hydroxy-3-iodophenyl)dibenzothiophenium bromide.

[0240] [ka]

[0241] (Synthesis Example 23) Synthesis of 5-(4-hydroxy-2-iodophenyl)-2-[(4-hydroxyphenyl)dimethoxymethyl]dibenzothiophenium nonafluorobutanesulfonate (sulfonium salt 13) The same procedure as in Synthesis Example 5 was carried out except that methanol was used instead of 2-iodoethanol, thereby obtaining 1.8 g of 5-(4-hydroxy-2-iodophenyl)-2-[(4-hydroxyphenyl)dimethoxymethyl]dibenzothiophenium-nonafluorobutanesulfonate (sulfonium salt 13).

[0242] [ka]

[0243] <Synthesis of sulfonium salt 14> (Synthesis Example 24) Synthesis of 4-methoxy-4'-phenylsulfanylbenzophenone The same procedure as in Synthesis Example 1 was carried out except that phenyl sulfide was used instead of dibenzothiophene to obtain 10 g of 4-methoxy-4'-phenylsulfanylbenzophenone.

[0244] [ka]

[0245] (Synthesis Example 25) Synthesis of 4-methoxy-4'-phenylsulfinylbenzophenone 9.0 g of 4-methoxy-4'-phenylsulfinylbenzophenone is obtained by carrying out the same procedure as in Synthesis Example 2, except that 4-methoxy-4'-phenylsulfanylbenzophenone is used instead of 2-(4-methoxybenzoyl)dibenzothiophene.

[0246] [ka]

[0247] (Synthesis Example 26) Synthesis of 4-[dimethoxy-(4-methoxyphenyl)methyl]phenyl phenyl sulfoxide 4.5 g of 4-[dimethoxy-(4-methoxyphenyl)methyl]phenyl phenyl sulfoxide was obtained by carrying out the same procedure as in Synthesis Example 3, except that 4-methoxy-4'-phenylsulfinylbenzophenone was used instead of 2-(4-methoxybenzoyl)dibenzothiophene-5-oxide.

[0248] [ka]

[0249] (Synthesis Example 27) Synthesis of 4-[dimethoxy-(4-methoxyphenyl)methyl]phenyldiphenylsulfonium bromide The same procedure as in Synthesis Example 4 was carried out except that 4-[dimethoxy-(4-methoxyphenyl)methyl]phenylphenyl sulfoxide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophene-5-oxide, to obtain 7.0 g of 4-[dimethoxy-(4-methoxyphenyl)methyl]phenyldiphenylsulfonium bromide.

[0250] [ka]

[0251] (Synthesis Example 28) Synthesis of 4-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 14) The same procedure as in Synthesis Example 5 was carried out except that 4-[dimethoxy-(4-methoxyphenyl)methyl]phenyldiphenylsulfonium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyl-dibenzothiophenium bromide, to obtain 1.1 g of 4-[bis(2-iodoethoxy)-(4-methoxyphenyl)methyl]phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 14).

[0252] [ka]

[0253] <Synthesis of sulfonium salt 15> (Synthesis Example 29) Synthesis of 4-(4-hydroxybenzoyl)phenyldiphenylsulfonium bromide The same procedure as in Synthesis Example 15 was carried out except that 4-[dimethoxy-(4-methoxyphenyl)methyl]phenyldiphenylsulfonium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide, to obtain 1.2 g of 4-(4-hydroxybenzoyl)phenyldiphenylsulfonium bromide.

[0254] [ka]

[0255] (Synthesis Example 30) Synthesis of 4-[(4-hydroxyphenyl)-bis(2-iodoethoxy)methyl]phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 15) The same procedure as in Synthesis Example 5 was carried out except that 4-(4-hydroxybenzoyl)phenyldiphenylsulfonium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyl-dibenzothiophenium bromide, to obtain 2.1 g of 4-[(4-hydroxyphenyl)-bis(2-iodoethoxy)methyl]phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 15).

[0256] [ka]

[0257] <Synthesis of sulfonium salt 16> (Synthesis Example 31) Synthesis of 4-iodophenyl[4-(4-methoxybenzoyl)phenyl]phenylsulfonium bromide 5.0 g of 4-iodophenyl[4-(4-methoxybenzoyl)phenyl]phenylsulfonium bromide was obtained by carrying out the same procedure as in Synthesis Example 10, except that 4-methoxy-4'-phenylsulfinylbenzophenone was used instead of 2-(4-methoxybenzoyl)dibenzothiophene-5-oxide.

[0258] [ka]

[0259] (Synthesis Example 32) Synthesis of 4-(4-hydroxybenzoyl)phenyl(4-iodophenyl)phenylsulfonium bromide The same procedure as in Synthesis Example 15 was carried out except that 4-iodophenyl[4-(4-methoxybenzoyl)phenyl]phenylsulfonium bromide was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium bromide, to obtain 1.2 g of 4-(4-hydroxybenzoyl)phenyl(4-iodophenyl)phenylsulfonium bromide.

[0260] [ka]

[0261] (Synthesis Example 33) Synthesis of 4-[(4-hydroxyphenyl)-dimethoxymethyl]phenyl(4-iodophenyl)phenylsulfonium nonafluorobutanesulfonate (sulfonium salt 16) The same procedure as in Synthesis Example 5 was carried out except that methanol was used instead of 2-iodoethanol, to obtain 1.8 g of 4-[(4-hydroxyphenyl)-dimethoxymethyl)]phenyl(4-iodophenyl)phenylsulfonium-nonafluorobutanesulfonate (sulfonium salt 16).

[0262] [ka]

[0263] <Synthesis of sulfonium salt 17> (Synthesis Example 34) Synthesis of 4-[(4-hydroxyphenyl)-bis(2-iodoethoxy)methyl]phenyl(4-iodophenyl)phenylsulfonium nonafluorobutanesulfonate (sulfonium salt 17) By carrying out the same procedure as in Synthesis Example 5 above, but using 4-(4-hydroxybenzoyl)phenyl(4-iodophenyl)phenylsulfonium bromide instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyl-dibenzothiophenium bromide, 2.3 g of 4-[(4-hydroxyphenyl)-bis(2-iodoethoxy)methyl]phenyl(4-iodophenyl)phenylsulfonium nonafluorobutanesulfonate (sulfonium salt 17) was obtained.

[0264] [ka]

[0265] <Synthesis of sulfonium salt 18> (Synthesis Example 35) Synthesis of 4-bromo-4'-phenylsulfanylbenzophenone Add 3.0 g of aluminum chloride to 28 g of methylene chloride and bring the temperature to 0°C. Add 4.0 g of diphenyl sulfide, then dissolve 3.4 g of 4-bromobenzoyl chloride in 6.8 g of methylene chloride and add dropwise over 30 minutes. After the dropwise addition, stir at 25°C for 1 hour, add 60 g of purified water, stir for an additional 5 minutes, and wash twice with 20 g of toluene. The mixture is separated, and the resulting organic layer is distilled off. The resulting residue is purified by recrystallization using 30 g of isopropyl alcohol to obtain 5.2 g of 4-bromo-4'-phenylsulfanylbenzophenone.

[0266] [ka]

[0267] (Synthesis Example 36) Synthesis of 4-bromo-4'-phenylsulfanylbenzophenone dimethyl acetal 5.0 g of 4-bromo-4'-phenylsulfanylbenzophenone obtained in Synthesis Example 35 above was dissolved in 30 g of methanol, and 5.0 g of trimethyl orthoformate and 30 mg of concentrated sulfuric acid were added and stirred at 60°C for 4 hours. After stirring, 150 g of 3% by mass sodium bicarbonate solution was added and stirred for an additional 10 minutes to precipitate a solid. The precipitated solid was filtered and redissolved in 30 g of methylene chloride. This was washed three times with water, and the methylene chloride was then distilled off to obtain 5.0 g of 4-bromo-4'-phenylsulfanylbenzophenone dimethyl acetal.

[0268] [ka]

[0269] (Synthesis Example 37) Synthesis of 4-{dimethoxy-[4-(phenylsulfanyl)phenyl]methyl}phenyldiphenylsulfonium nonafluorobutanesulfonate A pre-dried flask was charged with 2.0 g of tetrahydrofuran, 0.4 g of magnesium, and 1,2-dibromoethane to activate the magnesium. After activation was confirmed, the solution was heated to 50°C and a solution of 4.0 g of 4-bromo-4'-phenylsulfanylbenzophenone dimethyl acetal (prepared in Synthesis Example 36) dissolved in 6.0 g of THF was added dropwise. The mixture was then stirred at 50°C for 5 hours to obtain a THF solution of 4-[dimethoxy-(4-phenylsulfanylphenyl)methyl]phenylmagnesium bromide. The THF solution of 4-[dimethoxy-(4-phenylsulfanylphenyl)methyl]phenylmagnesium bromide was added dropwise to a solution of 1.9 g of diphenyl sulfoxide, 1.8 g of trimethylsilyl chloride, and 0.8 g of triethylamine dissolved in 9.5 g of methylene chloride at temperatures below 10°C, followed by stirring at 25°C for 1 hour. After stirring, 30 g of 10% by weight ammonium chloride aqueous solution was added at 5°C or below, and the mixture was stirred for another 10 minutes. The mixture was then washed twice with 5.0 g of isopropyl ether. 40 g of methylene chloride and 3.1 g of potassium nonafluorobutanesulfonate were then added, and the mixture was stirred at 25°C for approximately 2 hours. The mixture was separated and washed three times with water, after which the methylene chloride was distilled off to obtain crude crystals. The crude crystals were purified by silica gel column chromatography (methylene chloride / methanol = 90 / 10 (volume ratio)) to obtain 3.2 g of 4-{dimethoxy-[4-(phenylsulfanyl)phenyl]methyl}phenyldiphenylsulfonium-nonafluorobutanesulfonate.

[0270] [ka]

[0271] (Synthesis Example 38) Synthesis of 4-{bis(2-iodoethoxy)-[4-(phenylsulfanyl)phenyl]methyl}phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 18) The same procedure as in Synthesis Example 5 was repeated, except that 4-{dimethoxy-[4-(phenylsulfanyl)phenyl]methyl}phenyldiphenylsulfonium-nonafluorobutanesulfonate was used instead of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyl-dibenzothiophenium bromide, to obtain 2.2 g of 4-{bis(2-iodoethoxy)-[4-(phenylsulfanyl)phenyl]methyl}phenyldiphenylsulfonium-nonafluorobutanesulfonate (sulfonium salt 18).

[0272] [ka]

[0273] <Synthesis of Polymer A> (Synthesis Example 39) Synthesis of Polymer A 8.0 g of polyhydroxystyrene and 0.010 g of 35% by weight aqueous hydrochloric acid solution were dissolved in 28 g of dehydrated dioxane. 2.73 g of cyclohexyl vinyl ether was dissolved in 2.80 g of dehydrated dioxane and added dropwise to the polyhydroxystyrene solution over 30 minutes. After the dropwise addition, the mixture was heated to 40°C and stirred for 2 hours. After stirring, the mixture was cooled and 0.014 g of dimethylaminopyridine was added. The solution was then dropped into 260 g of pure water to precipitate the polymer. The solid obtained by separating the polymer through vacuum filtration was washed twice with 300 g of pure water and then vacuum dried to obtain 9.2 g of Polymer A shown below as a white solid. Note that the monomer ratio of the polymer units in the present invention is not limited to the ratio shown below.

[0274] [ka]

[0275] <Synthesis of Polymer B> (Synthesis Example 40) Synthesis of Polymer B 7.0 g of acetoxystyrene, 2.1 g of t-butyl methacrylate, 0.022 g of butyl mercaptan, and 0.40 g of dimethyl-2,2'-azobis(2-methylpropionate) (AIBN) were dissolved in 35 g of tetrahydrofuran (THF) and deoxygenated. This solution was added dropwise over 4 hours to 20 g of THF, which had been brought to reflux temperature under a nitrogen stream. After the addition, the solution was stirred for 2 hours and then cooled to room temperature. The polymer was precipitated by adding the solution dropwise to a mixed solvent of 149 g of hexane and 12 g of THF. The precipitated polymer was separated by vacuum filtration, and the resulting solid was washed with 52 g of hexane and then vacuum dried to obtain 10.3 g of Polymer B, shown in the following formula, as a white solid. Note that the monomer ratio of the polymer units in the present invention is not limited to the ratio shown below.

[0276] [ka]

[0277] <Synthesis of Polymer C> (Synthesis Example 41) Synthesis of Polymer C 6.0 g of Polymer B, 6.0 g of triethylamine, 6.0 g of methanol, and 1.5 g of pure water were dissolved in 30 g of propylene glycol monomethyl ether and stirred at reflux temperature for 6 hours. The solution was then cooled to 25°C, and the resulting solution was added dropwise to a mixture of 30 g of acetone and 30 g of pure water to precipitate the polymer. The resulting solid was separated by vacuum filtration, washed twice with 30 g of pure water, and then vacuum dried to obtain 4.3 g of Polymer C, represented by the following formula, as a white solid. Note that the monomer ratio of the polymer units in the present invention is not limited to the following.

[0278] [ka]

[0279] <Synthesis of Polymer D> (Synthesis Example 42) Synthesis of Polymer D 7.8 g of polymer D represented by the following formula was obtained by the same procedure as in Synthesis Example 44, except that 5.8 g of sulfonium salt 2 obtained in Synthesis Example 6, 3.9 g of 5-methacryloyloxynorbornane-2,6-lactone, 4.2 g of 4-(1-ethoxyethoxy)phenyl methacrylate, and 3.2 g of 4-hydroxyphenyl methacrylate were used as monomers. Note that the monomer ratio of the polymer units in the present invention is not limited to the following.

[0280] [ka]

[0281] <Synthesis of Polymer E> (Synthesis Example 43) Synthesis of Polymer E 7.8 g of polymer E represented by the following formula was obtained by the same procedure as in Synthesis Example 40, except that 4.7 g of sulfonium salt 2 obtained in Synthesis Example 6, 8.0 g of 4-triphenyl(vinylphenyl)stannane, 4.2 g of 4-(1-ethoxyethoxy)phenyl methacrylate, and 3.2 g of 4-hydroxyphenyl methacrylate were used as monomers. Note that the monomer ratio of the polymer units in the present invention is not limited to the following.

[0282] [ka]

[0283] <Synthesis of Polymer F> (Synthesis Example 44) Synthesis of Polymer F (Comparative Polymer 1) Except for using 4.2 g of 2-[dimethoxy-(4-methoxyphenyl)methyl]-5-phenyldibenzothiophenium-1,1,2-trifluoro-4-methacryloyloxybutanesulfonate as a monomer, 3.9 g of 5-methacryloyloxynorbornane 2,6-lactone, 4.2 g of 4-(1-ethoxyethoxy)phenyl methacrylate, and 3.2 g of 4-hydroxyphenyl methacrylate, the same operation as in Synthesis Example 40 was performed to obtain 7.8 g of Polymer F represented by the following formula. Note that the monomer ratio of the units of the polymer in the present invention is not limited to the following.

[0284]

Chemical formula

[0285] <Synthesis of Polymer G> ​​​​​​​​​​​​​​​​​​​ As the PAG, any one of the sulfonium salts 1 and 3, and the sulfonium salts 6 to 9 and 14 shown below and the comparative sulfonium salts 1 and 2 was used.

[0288] [Chemical formula]

[0289] <EUV Acid Generation Efficiency Evaluation> After dropping and spin-coating on a 4-inch quartz wafer, a film with a thickness of 120 nm was formed by baking on a hot plate at 110 °C for 1 minute. The formed film was irradiated with 2.0 to 7.0 mJ / cm 2 using an EUV exposure apparatus (Energetic EQ-10m). After irradiation, the absorbance of the absorption (530 nm) generated by the reaction of the acid and coumarin 6 was measured using an ultraviolet-visible (UV-VIS) spectrophotometer. The acid generation efficiency per exposure dose was determined from the slope of the linear function of the exposure dose and the absorbance, and the relative acid generation efficiency based on the comparative sulfonium salt 2 was calculated. The results are shown in Table 1. Specifically, the acid generation efficiencies of each of Samples 1 to 9 of Examples 1 to 7 and Comparative Examples 1 to 2 were calculated as relative values with respect to the acid generation efficiency of Sample 9 (Comparative Example 2) added with the comparative sulfonium salt 2 being 1.00. The larger the numerical value of the acid generation efficiency, the more excellent the effect is shown.

[0290] [Table 1]

[0291] Samples 1 and 3 to 7 (Examples 1 and 3 to 7) containing sulfonium salts according to some embodiments of the present invention have higher acid generation efficiency than Comparative Examples 1 and 2 due to the inclusion of iodine or fluorine, which have high EUV absorption. On the other hand, Example 2 containing sulfonium salt 3 has a structure containing three fluorine atoms, but almost no acid generation was observed. Fluorine has high EUV absorption, but when it is contained in an acetal structure, EUV irradiation causes a side reaction that inhibits acid generation, and as a result, the acid generation efficiency upon EUV irradiation is significantly lower than that of Comparative Example 2.

[0292] A comparison of Examples 1, 3 and 4 shows that as the amount of iodine introduced increases, the EUV absorption efficiency increases and the acid generation efficiency improves.

[0293] [Examples 8 to 13 and Comparative Examples 3 to 4] <Electron beam sensitivity evaluation> A sample was prepared as follows: 100 mg of the polymer C, 0.024 mmol of each of the sulfonium salt 1, sulfonium salts 6 to 9, and 14 shown below, or comparative sulfonium salts 1 and 2 as a photoacid generator (PAG), and 0.010 mmol of an acid diffusion controller were added to 3,000 mg of cyclohexanone to prepare the sample.

[0294] <Electron beam sensitivity evaluation> The resist composition sample 1 is spin-coated onto a silicon wafer previously modified with hexamethylenedisilazane. This is pre-baked on a hot plate at 110°C for 1 minute to obtain a substrate on which a 100 nm thick coating film is formed. A 50 nm line and space pattern is then written onto the coating film on the substrate using an electron beam lithography system. After electron beam irradiation, the substrate is irradiated with 1000 mJ / cm of 395 nm UV-LED. 2 The entire surface was exposed to an exposure dose of E 100, and then heated on a hot plate at 110°C for 1 minute. The film was developed for 1 minute using a developer (product name: NMD-3, 2.38% by mass aqueous solution of tetramethylammonium hydroxide, manufactured by Tokyo Ohka Kogyo Co., Ltd.), and then rinsed with pure water to obtain a 50 nm line and space pattern. The electron beam exposure dose at this time was E size[μC / cm 2 The sensitivity to electron beam irradiation is calculated as [( ...))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))

[0295] In Table 2, the sensitivity of each sample was calculated as a relative value to the evaluation results of the samples (Examples 8 to 13 and Comparative Example 3) with the sensitivity of the sample containing comparative sulfonium salt 2 (Comparative Example 4) set at 100. A smaller relative sensitivity value indicates a more excellent effect.

[0296] [Table 2]

[0297] Sulfonium salts 1, 6 to 9, and 14, which have high EUV absorption, are preferred when used in a step of irradiating with ultraviolet light after irradiating with EUV or an electron beam, because they have high acid generation efficiency in EUV or an electron beam, and can form patterns with higher sensitivity in the subsequent UV irradiation than comparative sulfonium salt 1.

[0298] In the acid generation efficiency evaluation described above, sulfonium salt 7 (sample 4) has one more iodine than sulfonium salt 1 (sample 1), and therefore has a higher acid generation efficiency. However, when comparing Example 8 and Example 10, there is no difference in relative sensitivity. This is because R 5 and R 6 The presence of a 1-iodoethyl group as the hydroxyl group improves affinity by being eliminated or replaced by a hydroxyl group by tetramethylammonium hydroxide in an alkaline developer, which tends to improve the solubility of the sulfonium salt during development. [Industrial Applicability]

[0299] Some embodiments of the present invention provide a resin composition containing an onium salt that undergoes structural change to a ketone derivative by irradiation with a first active energy ray, such as an electron beam or extreme ultraviolet light, to generate an active species, and that can then be converted to a ketone derivative by irradiation with a second active energy ray. The onium salt has a specific substituent or a specific structure, specifically a benzothiophene structure, which improves absorption of the irradiated ultraviolet wavelength. Therefore, the resin composition containing the onium salt can be a highly sensitive resist composition that efficiently generates acid upon irradiation with ultraviolet light.

Claims

1. An onium salt represented by the following general formula (1) or the following general formula (2): The onium salt has at least one fluorine atom or iodine atom bonded to its structure as a substituent. 【Chemical 1】 (In the general formula (1), R １ and R ２ each independently represents at least one selected from the group consisting of an optionally substituted linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; an optionally substituted linear, branched or cyclic alkenyl group having 2 to 12 carbon atoms; an optionally substituted aryl group having 6 to 14 carbon atoms; and an optionally substituted heteroaryl group having 4 to 12 carbon atoms; The R 1 , R ２ and at least two or more of the aryl groups to which the sulfonium group is bonded may form a ring structure together with the sulfur atom to which they are bonded, either directly via a single bond or via at least one bond selected from the group consisting of a nitrogen-containing group, an oxygen atom, a sulfur atom and a methylene group, The R 1 and R ２ at least one methylene group in the formula (I) may be substituted with a divalent heteroatom-containing group; R ３ and R ４ each independently represents at least one selected from the group consisting of an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, an alkylsulfanyl group, an aryl group, a heteroaryl group, an aryloxy group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a (meth)acryloyloxy group, a hydroxy(poly)alkyleneoxy group, an amino group, a cyano group, a nitro group, and a halogen atom, wherein, when a carbon atom is present, the number of carbon atoms is 1 to 12, and these groups may have a substituent; R ５ and R ６ each independently represents at least one selected from the group consisting of an optionally substituted linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; an optionally substituted linear, branched or cyclic alkenyl group having 2 to 12 carbon atoms; an optionally substituted aryl group having 6 to 14 carbon atoms; and an optionally substituted heteroaryl group having 4 to 12 carbon atoms; The R ５ and R ６ may be bonded to each other directly via a single bond or via at least one atom selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring structure, The R ５ and R ６ at least one methylene group in the formula (I) may be substituted with a divalent heteroatom-containing group; L １ is at least one selected from the group consisting of a single bond; a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 2 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; a heteroarylene group having 4 to 12 carbon atoms; and a group formed by bonding any of these groups via a nitrogen atom-containing group, an oxygen atom or a sulfur atom; Y １ and Y ２ is an oxygen atom or a sulfur atom, n1 and n2 are independently an integer of 1 to 3; When n1 is 1, n3 is an integer of 0 to 4, when n1 is 2, n3 is an integer of 0 to 6, when n1 is 3, n3 is an integer of 0 to 8, When n2 is 1, n4 is an integer from 0 to 5, when n2 is 2, n4 is an integer from 0 to 7, when n2 is 3, n4 is an integer from 0 to 9, X － represents a monovalent counter anion. In the general formula (2), R １ ~R ６ , L １ , Y １ , Y ２ , n1, n2 and X － is R in the general formula (1). １ ~R ６ , L １ , Y １ , Y ２ , n1, n2 and X － are selected from the same options as each of L ２ is L in the general formula (1). １ Selected from the same options as When n1 is 1, n3 is an integer of 0 to 3, when n1 is 2, n3 is an integer of 0 to 5, when n1 is 3, n3 is an integer of 0 to 7, When n2 is 1, n4 is an integer from 0 to 4; when n2 is 2, n4 is an integer from 0 to 6; when n2 is 3, n4 is an integer from 0 to 8.

2. 2. The onium salt according to claim 1, wherein the onium salt is represented by the following general formula (3) or (4): 【Chemistry 2】 (In the general formulas (3) and (4), R ５ and R ６ has at least one iodine atom as a substituent, R 1 ~R ４ , L ２ , X － , Y １ , and Y ２ is R in the general formulas (1) and (2). 1 ~R ４ , L ２ , X － , Y １ and Y ２ are selected from the same options as each of In the general formula (3), n3 is an integer of 0 to 4, and n4 is an integer of 0 to 5. In the general formula (4), n3 is an integer of 0 to 3, and n4 is an integer of 0 to 4.

3. The onium salt according to claim 1 or 2, a polymer having an acid-reactive unit; A resist composition comprising:

4. A resist composition comprising a polymer having the onium salt structure according to claim 1 or 2 as unit A, The X － is covalently bonded to the polymer backbone, The resist composition, wherein the polymer further comprises an acid-reactive unit.

5. The resist composition according to claim 3 or 4, wherein the acid-reactive unit is at least one of a unit B represented by the following general formulas (5a) to (5d), or a unit C represented by a structure in which a compound represented by the following general formulas (5e) to (5f) is bonded to an Sp group of the following general formula (6) at any position of the compound: 【Chemistry 3】 (In the general formula (5a), R 7 is any one selected from the group consisting of a hydrogen atom, an alkyl group, and a halogenated alkyl group, R 8 ~R 10 are each independently a linear, branched or cyclic alkyl group which may have a substituent, 8 ~R 10 two or more of these may form a ring structure directly via a single bond or via any one selected from the group consisting of a nitrogen atom-containing group, an oxygen atom, a sulfur atom, and a methylene group, L ３ is any one selected from the group consisting of a single bond, a carbonyloxy group, a carbonylamino group, a linear, branched or cyclic alkylenecarbonyloxy group which may have a substituent, and an alkylenecarbonylamino group. In the general formula (5b), R 7 and L ３ is R in the general formula (5a) 7 and L ３ are selected from the same options as each of R 11 and R 12 are each independently any one selected from the group consisting of a hydrogen atom and a linear, branched or cyclic alkyl group; R 13 represents a linear, branched or cyclic alkyl group which may have a substituent, The R 11 ~R 13 Two or more of these may form a ring structure directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. In the general formula (5c), R 7 ~R 10 and L ３ is R in the general formula (5a) 7 ~R 10 and L ３ are selected from the same options as each of R 14 are each independently any one selected from the group consisting of an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an alkylsulfanyl group, an alkylsulfinyl group, an alkylsulfonyl group, an amino group, a cyano group, a nitro group, and a halogen atom; R 14 two or more of these may form a ring structure directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group, n5 is an integer of 1 to 2, n6 is an integer from 0 to 4 when n5 is 1, and an integer from 0 to 6 when n5 is 2; n7 is an integer from 1 to 5 when n5 is 1, and an integer from 1 to 7 when n5 is 2; n6+n7 is 1 to 5 when n5 is 1, and is 1 to 7 when n5 is 2. In the general formula (5d), R 7 , R 14 , L ３ , n5, n6 and n7 are R in the general formulas (5a) and (5c). 7 , R 14 , L ３ , n5, n6 and n7 are selected from the same options as each of R 11 ~R 13 is R in the general formula (5b). 11 ~R 13 are selected from the same options as each of the above. In the general formula (5e), ​​R １５ and R １６ are each independently any one selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group; R １５ and R １６ at least one of the groups is the electron-donating group, R １７ is any one selected from the group consisting of a hydrogen atom and an alkyl group which may have a substituent, L ４ is any one selected from the group consisting of a single bond; an oxygen atom; a sulfur atom; and a methylene group; n8 is an integer of 0 or 1, n9 and n10 are each an integer of 1 to 2, and n9+n10 is an integer of 2 to 4; When n9 is 1, n11 is an integer from 0 to 4, and when n9 is 2, n11 is an integer from 0 to 6; When n10 is 1, n12 is an integer from 0 to 4, and when n10 is 2, n12 is an integer from 0 to 6; n11 is 2 or more and R １５ is an electron donating group or an electron withdrawing group, two R １５ may form a ring structure together directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group, n12 is 2 or more and R １６ is an electron donating group or an electron withdrawing group, two R １６ may form a ring structure with each other directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group. In the general formula (5f), R １８ are each independently any one selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group; R １８ at least one of the groups is the electron-donating group, R １９ is any one selected from the group consisting of a hydrogen atom; an alkyl group which may have a substituent; and an alkenyl group which may have a substituent; １９ at least one methylene group in the formula (I) may be substituted with a divalent heteroatom-containing group; R ２０ is R in the general formula (5e). １７ are selected from the same options as n14 is an integer from 0 to 7, n13 is 1 or 2, and when n13 is 1, n14 is an integer of 0 to 5, and when n13 is 2, n14 is an integer of 0 to 7; n14 is 2 or more and R １８ is an electron donating group or an electron withdrawing group, two R １８ may form a ring structure with each other directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom and a methylene group.) 【Chemistry 4】 In the general formula (6), L ５ is any one selected from the group consisting of a carbonyloxy group, a phenylenediyl group, a naphthalenediyl group, a phenylenediyloxy group, a naphthalenediyloxy group, a phenylenediylcarbonyloxy group, a naphthalenediylcarbonyloxy group, a phenylenediyloxycarbonyl group, and a naphthalenediyloxycarbonyl group, Sp is any one of a single bond; an optionally substituted linear, branched or cyclic alkylene group having 1 to 6 carbon atoms; and an optionally substituted linear, branched or cyclic alkenylene group having 1 to 6 carbon atoms, wherein at least one methylene group in Sp is optionally substituted with a divalent heteroatom-containing group, R ２１ is any one selected from the group consisting of a hydrogen atom; a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms; and a linear, branched, or cyclic alkenyl group having 2 to 6 carbon atoms; ２１ at least one hydrogen atom in the alkyl group and the alkenyl group may be substituted with a fluorine atom, * indicates the bonding site with the compound represented by the general formula (5e) or (5f).

6. 6. The resist composition according to claim 3, wherein the polymer contains a unit D having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi and Te.

7. A step of applying the resist composition according to any one of claims 3 to 6 onto a substrate to form a resist film; irradiating the resist film with first active energy rays; irradiating the resist film after the first active energy ray irradiation with a second active energy ray; and developing the resist film after the second actinic ray irradiation to obtain a pattern.

8. The method for manufacturing a device according to claim 7 , wherein the wavelength of the first active energy ray is shorter than the wavelength of the second active energy ray.

9. The method for manufacturing a device according to claim 7 or 8, wherein the first actinic energy ray is an electron beam or extreme ultraviolet ray.

10. The method for manufacturing a device according to any one of claims 7 to 9, further comprising a step of heating the resist film with an electric heating wire or a laser between the step of irradiating the resist film with the first active energy rays and the step of irradiating the resist film with the second active energy rays.

11. generating a first active species from the composition in the resist film by irradiation with the first active energy ray; causing a structural change of the onium salt by the first active species; The method for manufacturing a device according to any one of claims 7 to 10, wherein a second active species is generated from the structurally changed onium salt by irradiation with the second active energy ray.

12. The method for producing a device according to claim 11, wherein the structurally changed onium salt is a ketone derivative.

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