Photosensitive composition and method for producing patterned cured film

Abstract

To provide a photosensitive composition having both etching resistance and lithography characteristics and capable of forming a pattern of fine dimensions, and a method for producing a patterned cured film.SOLUTION: The photosensitive composition includes a silicon-containing polymer (A) having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group, and a photoacid generator (B), wherein the photoacid generator (B) includes a photoacid generator (B1) having a sulphonium cation containing an iodine atom.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a photosensitive composition and a method for producing a patterned cured film. [Background technology]

[0002] In the manufacture of electronic components, a laminate in which a resist film is formed on a substrate such as a silicon wafer using a resist material is subjected to a process including etching. For example, a process is performed in which a resist pattern is formed on the resist film by selectively exposing the resist film, and then dry etching is performed using the resist film as a mask to form a pattern on the substrate.

[0003] In recent years, advances in lithography technology have led to rapid advances in the miniaturization of patterns in the manufacturing of semiconductor devices and liquid crystal display devices. A common method for miniaturizing patterns is to shorten the wavelength (increase the energy) of the exposure light source.

[0004] Resist materials are required to have lithography properties such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with minute dimensions. To satisfy these requirements, a chemically amplified resist composition has been used, which contains a base component whose solubility in a developer changes due to the action of acid, and an acid generator component that generates acid upon exposure. Chemically amplified resist compositions generally use resins having multiple structural units in order to improve lithography properties, etc. Furthermore, chemically amplified resist compositions have been proposed that use, in addition to an acid generator component, an acid diffusion controller that controls the diffusion of acid generated from the acid generator component upon exposure.

[0005] Furthermore, resist materials are required to have etching resistance in order to function as a mask for substrate processing, and therefore silicon-containing compounds are sometimes used as base components from the viewpoint of etching resistance. For example, Patent Document 1 discloses a resist composition containing a silicon-containing resin, an acid generator component, and a photodegradable base that controls acid diffusion in order to accommodate pattern miniaturization and etching processing. In the Examples of Patent Document 1, a pattern on the order of several μm is formed by irradiation with a KrF excimer laser, and a 50 nm pattern is formed by electron beam drawing. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-59575 Summary of the Invention [Problem to be solved by the invention]

[0007] With the further advancement of lithography technology and the expansion of its application fields, patterns are rapidly becoming finer. Accordingly, when manufacturing semiconductor devices, etc., technology that can form fine patterns with good shapes is required. For example, in lithography using EUV (extreme ultraviolet), the goal is to form fine patterns of a dozen nanometers. As pattern dimensions become smaller, it becomes more difficult to achieve both etching resistance and lithography properties.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a photosensitive composition that has both etching resistance and lithography properties and is capable of forming a pattern with fine dimensions, and a method for producing a patterned cured film. [Means for solving the problem]

[0009]

[0009] In order to solve the above problems, the present inventors conducted extensive research and found that the above problems can be solved by using a silicon-containing polymer having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group, together with a specific photoacid generator, and thus completed the present invention. Specifically, the present invention provides the following.

[0010] The first aspect of the present invention is a composition comprising a silicon-containing polymer (A) having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group, and a photoacid generator (B), In the photosensitive composition, the photoacid generator (B) comprises a photoacid generator (B1) having a sulfonium cation containing an iodine atom.

[0011] The second aspect is a method for producing a coating film of the photosensitive composition of the first aspect on a support; exposing the coating film to position-selective light; and developing the exposed coating film to form a patterned cured film. A method for producing a patterned cured film. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a photosensitive composition that has both etching resistance and lithography properties and is capable of forming a pattern with fine dimensions, and a method for producing a patterned cured film. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments and can be implemented with appropriate modifications within the scope of the object of the present invention.

[0014] ≪Photosensitive composition≫ The photosensitive composition of this embodiment contains a silicon-containing polymer (A) having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group, and a photoacid generator (B). The photoacid generator (B) contains a photoacid generator (B1) having a sulfonium cation containing an iodine atom. The photosensitive composition of this embodiment can exhibit excellent etching resistance and lithography properties whether used as a positive-working or negative-working photosensitive composition, but these properties are more easily exhibited when used as a positive-working photosensitive composition.

[0015] <Silicon-containing polymer (A)> The photosensitive composition contains a silicon-containing polymer (A) having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group. The silicon-containing polymer (A) contains a phenolic hydroxyl group, an alkali-soluble group protected by an acid-dissociable group, and a silicon atom in the same polymer. The term "acid-dissociable group" refers to either (i) a group having acid dissociability in which the bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group can be cleaved by the action of an acid, or (ii) a group in which a portion of the bond is cleaved by the action of an acid, followed by a decarboxylation reaction, in which the bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group can be cleaved. The use of the silicon-containing polymer (A) enhances the etching resistance of the cured film formed from the photosensitive composition. Furthermore, the acid generated from the photoacid generator (B) upon exposure dissociates the acid-dissociable groups in the silicon-containing polymer (A), generating alkali-soluble groups. This makes the silicon-containing polymer (A) soluble in an alkaline developer. Therefore, when the photosensitive composition is exposed regioselectively, the exposed areas are soluble in the alkaline developer. Therefore, the photosensitive composition has photolithographic properties that allow it to be patterned by regioselective exposure and development with an alkaline developer.

[0016] The content of silicon atoms in the silicon-containing polymer (A) is preferably 10% by mass or more and 30% by mass or less, and more preferably 15% by mass or more and 25% by mass or less, based on the total mass of all atoms constituting the silicon-containing polymer. When the silicon atom content in the silicon-containing polymer (A) is equal to or greater than the lower limit of the above-mentioned preferred range, a cured film having excellent etching resistance is easily formed. On the other hand, when the silicon atom content is equal to or less than the upper limit of the above-mentioned preferred range, the lithography properties of the photosensitive composition are good.

[0017] The content of silicon atoms in the silicon-containing polymer (A) can be calculated by the following formula. The atomic weight used in the calculation of the formula below is the atomic weight value corrected based on the abundance ratio of the isotopes, rounded to two decimal places. The content (%) of silicon atoms calculated by the formula below is a value rounded to two decimal places. Silicon atom content (%) = (number of silicon atoms present in silicon-containing polymer (A) × atomic weight of silicon atoms) / (sum of the number of each atom constituting silicon-containing polymer (A) multiplied by the atomic weight of each atom) × 100 The content of silicon atoms can be, for example, -[Si(H)O 3 / 2 In the case of a polysiloxane having a repeating structure of structural units represented by the formula: ]-, the ratio is {(28.09 x 1) / {(28.09 x 1) + (16.00 x 1.5) + (1.01 x 1)} x 100] ≈ 52.9 mass%.

[0018] Suitable examples of the silicon-containing polymer (A) include polysilanes and polysiloxanes. As the silicon-containing polymer (A), polysiloxanes are preferred, and polysiloxanes containing silsesquioxane units are more preferred. The silicon-containing polymer (A) will be explained below using polysiloxane as an example. The polysiloxane is not particularly limited as long as it is a resin having a main chain composed of siloxane bonds (Si-O-Si). The polysiloxane may be a linear polysiloxane, a branched polysiloxane, or a silsesquioxane. The silsesquioxane may be any of a cage silsesquioxane, an incomplete cage silsesquioxane, a ladder silsesquioxane, and a random silsesquioxane. The polysiloxane may have a combination of a linear polysiloxane skeleton and / or a branched polysiloxane skeleton with a silsesquioxane skeleton.

[0019] [Constituent unit (a1)] The polysiloxane preferably contains a structural unit (a1) represented by the following formula (a1). [ka] (In formula (a1), R a11 is an organic group having a phenolic hydroxyl group, and * is a bond.

[0020] R a11 The number of carbon atoms in the organic group as the alkyl group is preferably 6 or more and 40 or less, more preferably 6 or more and 20 or less, and even more preferably 6 or more and 10 or less.

[0021] R a11 The organic group is preferably a hydrocarbon group having a phenolic hydroxyl group. The hydrocarbon group having a phenolic hydroxyl group is a hydrocarbon group containing an aromatic hydrocarbon group, in which the aromatic hydrocarbon group is substituted with one or more hydroxyl groups.

[0022] The aromatic hydrocarbon group referred to here is a group consisting of only an aromatic hydrocarbon ring or two or more aromatic hydrocarbon rings linked via a single bond. The aromatic hydrocarbon ring may be a single ring or a fused ring in which two or more rings are fused. Specific examples of the aromatic hydrocarbon ring constituting the aromatic hydrocarbon group include a benzene ring, a fluorene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and a biphenyl ring. The hydrocarbon group containing an aromatic hydrocarbon group may consist solely of an aromatic hydrocarbon group, or may be a combination of an aromatic hydrocarbon group and an aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, with saturated aliphatic hydrocarbon groups being preferred. Examples of the hydrocarbon group constituting the hydrocarbon group having a phenolic hydroxyl group include a group in which one hydrogen atom has been removed from the above-mentioned aromatic hydrocarbon ring, and a group in which one hydrogen atom of the above-mentioned aromatic hydrocarbon ring has been substituted with an alkylene group. The number of carbon atoms in the alkylene group substituting the hydrogen atom on the aromatic hydrocarbon ring is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1. A group in which one hydrogen atom has been removed from an aromatic hydrocarbon ring is an aromatic hydrocarbon group (aryl group). Specific preferred examples of the aromatic hydrocarbon group include a phenyl group, a naphthalene-1-yl group, and a naphthalene-2-yl group. A group in which one hydrogen atom of the aromatic hydrocarbon ring has been substituted with an alkylene group is an aralkyl group. Specific preferred examples of the aralkyl group include a benzyl group, a phenethyl group, a naphthalene-1-ylmethyl group, a naphthalene-2-ylmethyl group, a 2-(naphthalene-1-yl)ethyl group, and a 2-(naphthalene-2-yl)ethyl group.

[0023] R a11 is an organic group having a phenolic hydroxyl group, the organic group may consist solely of an aromatic group, or may be a combination of an aromatic group and an aliphatic group. The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group. The aliphatic group may be a chain aliphatic group, a cyclic aliphatic group, or a combination of a chain aliphatic group and a cyclic aliphatic group. When the aliphatic group is a cyclic aliphatic group, the cyclic aliphatic group may form a condensed ring together with the aromatic group. R a11 When is an organic group having a phenolic hydroxyl group, the organic group may have a substituent on the aromatic group or the aliphatic group, such as a carboxy group, a hydroxy group, an amino group, a sulfo group, a halogen atom, a halogenated alkyl group, an alkoxy group, an alkyloxycarbonyl group, or a nitro group. R a11 is an organic group having a phenolic hydroxyl group, the aliphatic group may contain a bond containing a heteroatom, such as -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, =N-, -NH-C(=NH)-, -S-, -S(=O)2-, -S(=O)2-O-, and combinations of two or more selected from these. H in the bond containing a heteroatom may be substituted with an alkyl group such as a methyl group or an ethyl group, or an acyl group such as an acetyl group, a propionyl group, or a benzoyl group.

[0024] The structural unit (a1) is preferably a structural unit (a1-1) represented by the following formula (a1-1). [ka] (In formula (a1-1), Ar a1 is an aromatic hydrocarbon group, and R a12 is a single bond or a divalent linking group, and R a13 is a hydrocarbon group having 1 to 6 carbon atoms or a halogen atom, na1 is an integer of 1 to 3, na2 is an integer of 0 to 4, and * is a bond.

[0025] Ar a1 is an aromatic hydrocarbon group with a valence of (na1+na2+1). a1 The aromatic hydrocarbon group may be a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group. The polycyclic aromatic hydrocarbon group may be a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group, or may be a group in which one or more aromatic hydrocarbon groups are bonded via a single bond to a monocyclic aromatic hydrocarbon group or a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, and a phenanthrene ring. Among these, a benzene ring and a naphthalene ring are preferred, and a benzene ring is more preferred.

[0026] R a12 Examples of the divalent linking group as include a divalent hydrocarbon group which may have a substituent. R a12 The hydrocarbon group as R may be an aliphatic hydrocarbon group or a combination of an aliphatic hydrocarbon group and an aromatic hydrocarbon group. a12 is not an aromatic hydrocarbon group. a12 is an aromatic hydrocarbon group, R a12 The aromatic hydrocarbon group as Ara1 This is because it constitutes a part of the aromatic hydrocarbon group.

[0027] R a12 The aliphatic hydrocarbon group as may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, and is preferably a saturated aliphatic hydrocarbon group. R a12 The aliphatic hydrocarbon group as R may be a chain aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or a combination of a chain aliphatic hydrocarbon group and an alicyclic hydrocarbon group. a12 The chain aliphatic hydrocarbon group contained in the aliphatic hydrocarbon group as may be linear or branched.

[0028] The linear aliphatic hydrocarbon group preferably has 1 or more and 10 or less carbon atoms, more preferably 1 or more and 6 or less, even more preferably 1 or more and 4 or less, and most preferably 1 or more and 3 or less carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, such as a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], or a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group preferably has 2 or more and 10 or less carbon atoms, more preferably 2 or more and 6 or less carbon atoms, and even more preferably 2 or 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group. Specific examples include alkylmethylene groups such as -CH(CH)-, -CH(CHCH)-, -C(CH)-, -C(CH)(CHCH)-, -C(CH)(CHCHCH)-, and -C(CHCH)-; alkylethylene groups such as -CH(CH)CH-, -CH(CH)CH(CH)-, -C(CH)CH-, -CH(CHCH)CH-, and -C(CHCH)-CH-; alkyltrimethylene groups such as -CH(CH)CHCH- and -CHCH(CH)CH-; and alkyltetramethylene groups such as -CH(CH)CHCHCHCH- and -CHCH(CH)CHCH-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0029] The linear or branched aliphatic hydrocarbon group may have a substituent, such as a fluorine atom or a fluorinated alkyl group having from 1 to 5 carbon atoms and substituted with a fluorine atom. In the linear or branched aliphatic hydrocarbon group, at least some of the methylene groups may be substituted with a divalent group other than methylene, such as -O-, -S-, and -C(=O)-.

[0030] The alicyclic hydrocarbon group preferably has 3 or more and 20 or less carbon atoms, and more preferably has 3 or more and 12 or less carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 or more and 6 or less carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane. The polycycloalkane preferably has 7 or more and 12 or less carbon atoms. Specific examples of polycycloalkanes include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0031] The alicyclic hydrocarbon group may or may not have a substituent, which may include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as the substituent is preferably an alkoxy group having from 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, or a tert-butyloxy group, and still more preferably a methoxy group or an ethoxy group. The halogen atom as the substituent is preferably a fluorine atom. Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl groups mentioned above have been substituted with the halogen atoms mentioned above. In the alicyclic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a group containing a heteroatom, and the heteroatom-containing group is preferably -O-, -C(=O)-O-, -S-, -S(=O)2-, or -S(=O)2-O-.

[0032] R a12is preferably a single bond or a linear or branched aliphatic hydrocarbon group which may have a substituent, more preferably a single bond or a linear or branched aliphatic hydrocarbon group, and even more preferably a linear or branched aliphatic hydrocarbon group. As the linear or branched aliphatic hydrocarbon group, an alkylene group having 1 to 6 carbon atoms is preferred, more preferably an alkylene group having 1 to 5 carbon atoms, more preferably a methylene group, ethylene group, propane-1,3-diyl group, propane-2,2-diyl group, and propane-1,2-diyl group, and particularly preferably a methylene group and ethylene group, and most preferably a methylene group.

[0033] R a13 The hydrocarbon group as R may be any of a linear hydrocarbon group, a branched hydrocarbon group, a cyclic hydrocarbon group, or a combination of two or more of these, and is preferably a linear hydrocarbon group or a branched hydrocarbon group. a13 The hydrocarbon group as may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, with a saturated hydrocarbon group being preferred. R a13 The number of carbon atoms in the hydrocarbon group represented by R is preferably 1 or more and 5 or less. a13 As the hydrocarbon group for , a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are more preferred, a methyl group and an ethyl group are even more preferred, and a methyl group is particularly preferred.

[0034] Preferably, na1 is 1. na2 is preferably an integer of 0 or more and 2 or less, more preferably 0 or 1, and even more preferably 0.

[0035] Specific examples of the structural unit (a1-1) are shown below. [ka]

[0036] The structural unit (a1-1) contained in the polysiloxane may be of one type or of two or more types. The proportion of the structural unit (a1-1) in the polysiloxane is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, based on the total (100 mol%) of all structural units constituting the polysiloxane. This proportion is preferably 80 mol% or less, more preferably 75 mol% or less, and even more preferably 70 mol% or less. When the proportion of the structural unit (a1-1) is within the above range, the photosensitive composition exhibits good lithography properties, and it is easy to form a patterned resin film that has excellent etching resistance.

[0037] [Constituent unit (a2)] The polysiloxane preferably contains a structural unit (a2) represented by the following formula (a2). [ka] (In formula (a2), R a21 is an organic group having an alkali-soluble group protected by an acid-labile group, and * is a bond.

[0038] R a21 is preferably a group represented by the following formula (a2-1) or a group represented by the following formula (a2-2). [ka] (In formula (a2-1), L a1 is a single bond or a divalent organic group, and R a22 is a hydrogen atom or a hydrocarbon group which may have a substituent, and R a23 is a hydrogen atom or a hydrocarbon group which may have a substituent, and R a22 , and R a23 may be bonded to each other to form a ring, and * represents a bond.) [ka] (In formula (a2-2), L a2 is a single bond or a divalent organic group, and X a2 is a single bond or O, and R a24 , R a25 , and Ra26 are each independently a hydrocarbon group, and R a24 , R a25 , and R a26 Two or more of may be bonded to each other to form a ring, and * represents a bond.)

[0039] (Group represented by formula (a2-1)) L a1 The divalent organic group as may be a divalent hydrocarbon group which may have a substituent. L a1 The hydrocarbon group as may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination of an aliphatic hydrocarbon group and an aromatic hydrocarbon group.

[0040] L a1 The aliphatic hydrocarbon group as may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, and is preferably a saturated aliphatic hydrocarbon group. L a1 The aliphatic hydrocarbon group as L may be a chain aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or a combination of a chain aliphatic hydrocarbon group and an alicyclic hydrocarbon group. a1 The chain aliphatic hydrocarbon group contained in the aliphatic hydrocarbon group as may be linear or branched.

[0041] The linear aliphatic hydrocarbon group preferably has 1 or more and 10 or less carbon atoms, more preferably 1 or more and 6 or less, even more preferably 1 or more and 4 or less, and most preferably 1 or more and 3 or less carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, such as a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], or a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group preferably has 2 or more and 10 or less carbon atoms, more preferably 2 or more and 6 or less carbon atoms, and even more preferably 2 or 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group. Specific examples include alkylmethylene groups such as -CH(CH)-, -CH(CHCH)-, -C(CH)-, -C(CH)(CHCH)-, -C(CH)(CHCHCH)-, and -C(CHCH)-; alkylethylene groups such as -CH(CH)CH-, -CH(CH)CH(CH)-, -C(CH)CH-, -CH(CHCH)CH-, and -C(CHCH)-CH-; alkyltrimethylene groups such as -CH(CH)CHCH- and -CHCH(CH)CH-; and alkyltetramethylene groups such as -CH(CH)CHCHCHCH- and -CHCH(CH)CHCH-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0042] The linear or branched aliphatic hydrocarbon group may have a substituent, such as a fluorine atom or a fluorinated alkyl group having from 1 to 5 carbon atoms and substituted with a fluorine atom. In the linear or branched aliphatic hydrocarbon group, at least some of the methylene groups may be substituted with a divalent group other than methylene, such as -O-, -S-, and -C(=O)-.

[0043] L a1 The aromatic hydrocarbon group may be a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group. The polycyclic aromatic hydrocarbon group may be a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group, or may be a group in which one or more aromatic hydrocarbon groups are bonded via a single bond to a monocyclic aromatic hydrocarbon group or a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, and a phenanthrene ring. Among these, a benzene ring, a naphthalene ring, and a biphenyl ring are preferred, and a benzene ring is more preferred.

[0044] The aromatic hydrocarbon group may or may not have a substituent, which may include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

[0045] L a1 is preferably a single bond or a group represented by the following formula (a2-1a): *-R a211 -X a1 -Ar a2 -** (a2-1a) (In formula (a2-1a), R a211 is a single bond or an alkylene group, and X a1 is a single bond, O, or S, and Ar a2 represents an aromatic hydrocarbon group which may have a substituent, * represents a bond to Si in formula (a2), and ** represents a bond to O in formula (a2-1).

[0046] R a211 The alkylene group as the alkylene group preferably has 1 or more and 10 or less carbon atoms, more preferably 1 or more and 5 or less carbon atoms, and still more preferably 1 or more and 3 or less carbon atoms. R a211 The alkylene group as may be linear or branched, but is preferably linear.

[0047] X a1 is preferably a single bond.

[0048] Ar a2The aromatic hydrocarbon group may be a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group. The polycyclic aromatic hydrocarbon group may be a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group, or may be a group in which one or more aromatic hydrocarbon groups are bonded via a single bond to a monocyclic aromatic hydrocarbon group or a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, and a phenanthrene ring. Among these, a benzene ring, a naphthalene ring, and a biphenyl ring are preferred, and a benzene ring is more preferred.

[0049] R a22 The hydrocarbon group is preferably an alkyl group. The number of carbon atoms in the alkyl group is preferably 1 to 10, and more preferably 1 to 5. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. R a22 is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom or a methyl group.

[0050] R a23 The hydrocarbon group is preferably an alkyl group. The number of carbon atoms in the alkyl group is preferably 1 to 10, and more preferably 1 to 5. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. R a23 As the alkyl group, an alkyl group having 1 to 5 carbon atoms is preferred, and a methyl group or an ethyl group is more preferred.

[0051] R a22 , and R a23 Examples of the substituent that the hydrocarbon group may have include a halogen atom and a hydroxyl group.

[0052] Ra22 , and R a23 The ring formed by bonding is preferably a 4- to 7-membered ring, more preferably a 4- to 6-membered ring. Specific examples of the ring formed include a tetrahydropyran ring and a tetrahydrofuran ring.

[0053] Specific examples of the group represented by formula (a2-1) are shown below. [ka]

[0054] (Group represented by formula (a2-2)) L a2 The divalent organic group as may be a divalent hydrocarbon group which may have a substituent. L a2 The hydrocarbon group as may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination of an aliphatic hydrocarbon group and an aromatic hydrocarbon group.

[0055] L a2 The aliphatic hydrocarbon group as may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, and is preferably a saturated aliphatic hydrocarbon group. L a2 The aliphatic hydrocarbon group as L may be a chain aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or a combination of a chain aliphatic hydrocarbon group and an alicyclic hydrocarbon group. a2 The chain aliphatic hydrocarbon group contained in the aliphatic hydrocarbon group as may be linear or branched.

[0056] The linear aliphatic hydrocarbon group preferably has 1 or more and 10 or less carbon atoms, more preferably 1 or more and 6 or less, even more preferably 1 or more and 4 or less, and most preferably 1 or more and 3 or less carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, such as a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], or a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group preferably has 2 or more and 10 or less carbon atoms, more preferably 2 or more and 6 or less carbon atoms, and even more preferably 2 or 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group. Specific examples include alkylmethylene groups such as -CH(CH)-, -CH(CHCH)-, -C(CH)-, -C(CH)(CHCH)-, -C(CH)(CHCHCH)-, and -C(CHCH)-; alkylethylene groups such as -CH(CH)CH-, -CH(CH)CH(CH)-, -C(CH)CH-, -CH(CHCH)CH-, and -C(CHCH)-CH-; alkyltrimethylene groups such as -CH(CH)CHCH- and -CHCH(CH)CH-; and alkyltetramethylene groups such as -CH(CH)CHCHCHCH- and -CHCH(CH)CHCH-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0057] The linear or branched aliphatic hydrocarbon group may have a substituent, such as a fluorine atom or a fluorinated alkyl group having from 1 to 5 carbon atoms and substituted with a fluorine atom. In the linear or branched aliphatic hydrocarbon group, at least some of the methylene groups may be substituted with a divalent group other than methylene, such as -O-, -S-, and -C(=O)-.

[0058] L a2The number of carbon atoms in the alicyclic hydrocarbon group as the cycloaliphatic hydrocarbon group is preferably 3 or more and 20 or less, more preferably 3 or more and 12 or less. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 or more and 6 or less carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane. The polycycloalkane preferably has 7 or more and 12 or less carbon atoms. Specific examples of polycycloalkanes include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0059] The alicyclic hydrocarbon group may or may not have a substituent, which may include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

[0060] L a2 The aromatic hydrocarbon group may be a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group. The polycyclic aromatic hydrocarbon group may be a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group, or may be a group in which one or more aromatic hydrocarbon groups are bonded via a single bond to a monocyclic aromatic hydrocarbon group or a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, and a phenanthrene ring. Among these, a benzene ring, a naphthalene ring, and a biphenyl ring are preferred, and a benzene ring is more preferred.

[0061] The aromatic hydrocarbon group may or may not have a substituent, which may include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

[0062] L a2 is preferably a single bond or a group represented by the following formula (a2-2a): *-R a221 -Ar a3 -** (a2-2a) (In formula (a2-1a), R a221 is a single bond or an alkylene group, and Ar a3 represents an alicyclic hydrocarbon group which may have a substituent, or an aromatic hydrocarbon group which may have a substituent, * represents a bond to Si in formula (a2), and ** represents X in formula (a2-2). a2 )

[0063] R a221 The alkylene group as the alkylene group preferably has 1 or more and 10 or less carbon atoms, more preferably 1 or more and 5 or less carbon atoms, and still more preferably 1 or more and 3 or less carbon atoms. R a211 The alkylene group as may be linear or branched, but is preferably linear.

[0064] Ar a3The number of carbon atoms in the alicyclic hydrocarbon group as the cycloaliphatic hydrocarbon group is preferably 3 or more and 20 or less, more preferably 3 or more and 12 or less. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 or more and 6 or less carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane. The polycycloalkane preferably has 7 or more and 12 or less carbon atoms. Specific examples of polycycloalkanes include norbornane, isobornane, tricyclodecane, and tetracyclododecane. Of these, adamantane or norbornane is preferred, and norbornane is more preferred.

[0065] Ar a3 The aromatic hydrocarbon group may be a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group. The polycyclic aromatic hydrocarbon group may be a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group, or may be a group in which one or more aromatic hydrocarbon groups are bonded via a single bond to a monocyclic aromatic hydrocarbon group or a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, and a phenanthrene ring. Among these, a benzene ring, a naphthalene ring, and a biphenyl ring are preferred, and a benzene ring is more preferred.

[0066] R a24 , R a25 , and R a26 Examples of the hydrocarbon group include an alkyl group, an alkenyl group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group.

[0067] R a24, R a25 , and R a26 The number of carbon atoms in the alkyl group is preferably 1 or more and 10 or less, and more preferably 1 or more and 5 or less. The alkyl group is preferably a linear alkyl group, more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0068] R a24 , R a25 , and R a26 The number of carbon atoms in the alkenyl group as the alkyl group is preferably 1 or more and 10 or less, and more preferably 1 or more and 5 or less. The alkenyl group is preferably a linear alkenyl group, more preferably a vinyl group or a propenyl group, and even more preferably a vinyl group.

[0069] R a24 , R a25 , and R a26 The number of carbon atoms in the alicyclic hydrocarbon group as the cycloaliphatic hydrocarbon group is preferably 3 or more and 20 or less, more preferably 3 or more and 12 or less. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 or more and 6 or less carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane. The polycycloalkane preferably has 7 or more and 12 or less carbon atoms. Specific examples of polycycloalkanes include norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0070] R a24 , R a25 , and R a26The aromatic hydrocarbon group may be a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group. The polycyclic aromatic hydrocarbon group may be a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group, or may be a group in which one or more aromatic hydrocarbon groups are bonded via a single bond to a monocyclic aromatic hydrocarbon group or a group in which two or more aromatic rings are fused to a monocyclic aromatic hydrocarbon group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, and a phenanthrene ring. Among these, a benzene ring, a naphthalene ring, and a biphenyl ring are preferred, and a benzene ring is more preferred.

[0071] R a24 , R a25 , and R a26 However, when they do not bond to each other to form a ring, these groups are preferably alkyl groups having 1 to 5 carbon atoms, more preferably methyl groups or ethyl groups, and even more preferably methyl groups.

[0072] R a24 , R a25 , and R a26 Two or more of may be bonded to each other to form a ring. For example, R a24 , and R a25may be bonded to each other to form, together with the carbon atom to which they are bonded, an alicyclic hydrocarbon group having from 5 to 20 carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has from 3 to 6 carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane. The polycycloalkane preferably has from 7 to 12 carbon atoms. Specific examples of polycycloalkanes include norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these, a group in which one hydrogen atom has been removed from cyclohexane or cyclopentane is preferred.

[0073] Specific examples of the group represented by formula (a2-2) are shown below. [ka] [ka]

[0074] The structural unit (a2) contained in the polysiloxane may be one type or two or more types. The proportion of the structural unit (a2) in the polysiloxane is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, based on the total (100 mol%) of all structural units constituting the polysiloxane. This proportion is preferably 60 mol% or less, more preferably 50 mol% or less, and even more preferably 40 mol% or less. When the proportion of the structural unit (a2) is within the above range, the photosensitive composition exhibits good lithography properties, and it is easy to form a patterned resin film that has excellent etching resistance.

[0075] [Other building blocks] The polysiloxane may have other structural units in addition to the structural unit (a1) and the structural unit (a2). Examples of other structural units include the structural unit (a3) ​​represented by formula (a3-1) or formula (a3-2), the structural unit (a4) represented by formula (a4-1) or formula (a4-2), and the structural unit (a5) represented by formula (a5).

[0076] (Structural unit (a3)) The structural unit (a3) ​​is a structural unit represented by the following formula (a3-1) or (a3-2). [ka] (In the formula, R a31 ~R a33 are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a substituent, and * is a bond. By including the structural unit (a3), the properties of the cured film formed using the photosensitive composition can be easily controlled.

[0077] In formula (a3-1) and formula (a3-2), R a31 ~R a33 The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The structure of the aliphatic hydrocarbon group may be linear, branched, cyclic, or a combination of these structures. R a31 ~R a33 The aliphatic hydrocarbon group may have a substituent, such as a hydroxyl group, an alkoxy group having 1 to 5 carbon atoms, a mercapto group, or an amino group. R a31 ~R a33 is preferably a hydrogen atom, an alkyl group, or an alkenyl group. R a31 ~R a33 The number of carbon atoms in the alkyl group is preferably 1 or more and 5 or less, and more preferably 1 or more and 3 or less. R a31 ~R a33Examples of the alkyl group as include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-octyl group, an n-decyl group, an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and a 2-ethylhexyl group. Among these, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an isopropyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group are preferred, a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are more preferred, a methyl group and an ethyl group are even more preferred, and a methyl group is particularly preferred. R a31 ~R a33 The alkenyl group as the alkyl group preferably has 2 or more and 5 or less carbon atoms, and more preferably 2 or 3 carbon atoms. R a31 ~R a33 As the alkenyl group for , a vinyl group and an allyl group are preferred.

[0078] The structural unit (a3) ​​contained in the polysiloxane may be one type or two or more types. When the polysiloxane contains the structural unit (a3) ​​in addition to the structural unit (a1) and the structural unit (a2), the proportion of the structural unit (a3) ​​in the polysiloxane, relative to the total (100 mol%) of all structural units constituting the polysiloxane, is, for example, preferably 10 mol% or more and 60 mol% or less, more preferably 20 mol% or more and 55 mol% or less, and even more preferably 30 mol% or more and 50 mol% or less. When the proportion of the structural unit (a3) ​​is at least as large as the lower limit of the above-mentioned preferred range, a patterned resin film having particularly excellent etching resistance is easily formed. On the other hand, when the proportion is at most the upper limit of the above-mentioned preferred range, the lithography properties of the photosensitive composition are excellent.

[0079] (Structural unit (a4)) The structural unit (a4) is a structural unit represented by the following formula (a4-1) or (a4-2). The structural unit (a4) is useful for improving lithography properties. The introduction of the structural unit (a4) makes it easy to control the dissolution rate. [ka] (In formula (a4-1) and formula (a4-2), R a44 is a hydrocarbon group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and R a45 is a single bond or a divalent linking group; na3 is an integer of 0 to 5, and * is a bond.

[0080] R a44 The hydrocarbon group as R may be either linear or branched. a44 The hydrocarbon group as may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, with a saturated hydrocarbon group being preferred. R a44 The number of carbon atoms in the hydrocarbon group as R is preferably 1 or more and 5 or less, and more preferably 1 or more and 3 or less. a44 The hydrocarbon group as is preferably an alkyl group. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, and a neopentyl group. Among these, a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are preferred, a methyl group and an ethyl group are more preferred, and a methyl group is even more preferred. R a44 The number of carbon atoms in the alkoxy group as the aryl group is preferably 1 or more and 5 or less, and more preferably 1 or more and 3 or less. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, an isobutyloxy group, a tert-butyloxy group, an n-pentyloxy group, an isopentyloxy group, and a neopentyloxy group. Among these, a methoxy group, an ethoxy group, an n-propyloxy group, and an isopropyloxy group are preferred, a methoxy group and an ethoxy group are more preferred, and a methoxy group is even more preferred. na3 is preferably an integer of 0 or more and 3 or less, more preferably 0 or 1, and even more preferably 0. R a45 The divalent linking group represented by R in formula (a1-1) a12 The same applies to the divalent linking group as above. Preferred divalent linking groups include -Si(CH3)2-, -SiH(CH3)-, -Si(C6H5)(CH3)-, Si(C6H5)2-, - and -SiH(C6H5)-.

[0081] The structural unit (a4) contained in the polysiloxane may be of one type or two or more types. When the polysiloxane contains the structural unit (a4) in addition to the structural unit (a1) and the structural unit (a2), the proportion of the structural unit (a4) in the polysiloxane, relative to the total (100 mol%) of all structural units constituting the polysiloxane, is preferably 10 mol% or more and 60 mol% or less, more preferably 20 mol% or more and 55 mol% or less, and even more preferably 30 mol% or more and 50 mol% or less.

[0082] (Structural unit (a5)) The structural unit (a5) is a structural unit represented by the following formula (a5). The structural unit (a5) is useful for improving lithography properties. The introduction of the structural unit (a5) makes it easy to control the dissolution rate. [ka] (In formula (a5), * represents a bond.)

[0083] When the polysiloxane contains the structural unit (a5) in addition to the structural unit (a1) and the structural unit (a2), the proportion of the structural unit (a5) in the polysiloxane, relative to the total (100 mol%) of all structural units constituting the polysiloxane, is preferably 10 mol% or more and 60 mol% or less, more preferably 20 mol% or more and 55 mol% or less, and even more preferably 30 mol% or more and 50 mol% or less.

[0084] Specific examples of other structural units are shown below. [ka]

[0085] Among polysiloxanes, silsesquioxanes composed of a structural unit represented by formula (a1) and a structural unit represented by formula (a2); and silsesquioxanes having a structural unit represented by formula (a1), a structural unit represented by formula (a2), and a structural unit represented by formula (a5) are preferred.

[0086] The mass average molecular weight (Mw) (based on polystyrene equivalent by gel permeation chromatography (GPC)) of the silicon-containing polymer (A) such as polysiloxane is not particularly limited, and is, for example, 1,000 or more, preferably 1,000 to 10,000, more preferably 1,300 to 7,500, and even more preferably 1,500 to 5,000. When the Mw of the silicon-containing polymer (A) is equal to or less than the upper limit of the above-mentioned preferred range, the silicon-containing polymer (A) has excellent solubility in organic solvents. On the other hand, when the Mw of the silicon-containing polymer (A) is equal to or greater than the lower limit of the above-mentioned preferred range, a photosensitive composition with excellent lithography properties can be easily obtained, and a resin film with a well-patterned shape can be easily formed. The silicon-containing polymer (A) preferably has a mass average molecular weight (Mw) / number average molecular weight (Mn) ratio, i.e., a dispersity, of about 1 to 3, more preferably about 1.0 to 2.0, and even more preferably about 1.05 to 1.50. Such a silicon-containing polymer (A) can further improve the lithography properties of the photosensitive composition.

[0087] The mass ratio of the silicon-containing polymer (A) to the mass of the solid content of the photosensitive composition is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass to 75% by mass, particularly preferably 40% by mass to 70% by mass, and most preferably 50% by mass to 70% by mass. When the mass ratio of the silicon-containing polymer (A) is within the above preferred range, the etching resistance of the film formed using the photosensitive composition is good. The "solid content of the photosensitive composition" refers to the components constituting the photosensitive composition excluding the organic solvent (S).

[0088] <Photoacid generator (B)> The photoacid generator (B) includes a photoacid generator (B1) having a sulfonium cation containing an iodine atom, which enhances the usefulness of the composition, particularly as a photosensitive composition for EUV radiation.

[0089] [Photoacid generator (B1) having a sulfonium cation containing an iodine atom] The photoacid generator (B1) is a sulfonium salt having a sulfonium cation containing an iodine atom as the cation moiety.

[0090] (cation part) The sulfonium cation containing an iodine atom is preferably a sulfonium cation represented by the following formula (b1-1). [ka] (In formula (b1-1), R b11 is an iodine atom, or -R b111 -X b1 and R b111 is a divalent linking group that does not contain an aromatic group, and X b1 is an aromatic group substituted with an iodine atom, and R b12 is a fluorine atom, a hydroxyl group, a hydrocarbon group which may have a substituent, or an alkoxy group which may have a substituent, and R b13 , and R b14 are each independently a hydrocarbon group which may have a substituent, and R b13 , and Rb14 may be bonded to each other to form a ring, q1 is an integer of 1 or more and 4 or less, q2 is an integer of 0 or more and 3 or less, and the sum of q1 and q2 is 1 or more and 4 or less.

[0091] When q1 is an integer of 2 or more, multiple R b11 may be the same or different. When q2 is an integer of 2 or more, a plurality of R b12 may be the same or different.

[0092] R b111 The divalent linking group containing no aromatic group as is preferably a divalent aliphatic hydrocarbon group or a group represented by the following formula (b1-1a): -L b1 -R b112 -L b2 -* (b1-1a) (In formula (b1-1a), L b1 is an ester bond, an amide bond, or an ether bond, and L b2 is a single bond, an ester bond, an amide bond, or an ether bond, and R b112 is a single bond or an alkylene group, and * is X b1 )

[0093] R b111 The aliphatic hydrocarbon group as may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. R b111 Examples of the aliphatic hydrocarbon group include a linear aliphatic hydrocarbon group, a branched aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and a combination of two or more selected from these.

[0094] The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, such as a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], or a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group preferably has 2 or more and 10 or less carbon atoms, more preferably 2 or more and 6 or less carbon atoms, and even more preferably 2 or 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group. Specific examples include alkylmethylene groups such as -CH(CH)-, -CH(CHCH)-, -C(CH)-, -C(CH)(CHCH)-, -C(CH)(CHCHCH)-, and -C(CHCH)-; alkylethylene groups such as -CH(CH)CH-, -CH(CH)CH(CH)-, -C(CH)CH-, -CH(CHCH)CH-, and -C(CHCH)-CH-; alkyltrimethylene groups such as -CH(CH)CHCH- and -CHCH(CH)CH-; and alkyltetramethylene groups such as -CH(CH)CHCHCHCH- and -CHCH(CH)CHCH-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0095] The alicyclic hydrocarbon group preferably has 3 or more and 20 or less carbon atoms, and more preferably has 3 or more and 12 or less carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 or more and 6 or less carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane. The polycycloalkane preferably has 7 or more and 12 or less carbon atoms. Specific examples of polycycloalkanes include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0096] R b112 The number of carbon atoms in the alkylene group is preferably 1 or more and 5 or less, and more preferably 1 or more and 3 or less. R b112 The alkylene group as may be linear or branched, but is preferably linear. R b112 Examples of the alkylene group include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and a pentamethylene group [-(CH2)5-].

[0097] X b1 The aromatic group as is preferably an aromatic hydrocarbon group. Specific examples of the aromatic hydrocarbon ring constituting the aromatic hydrocarbon group include a benzene ring, a fluorene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and a biphenyl ring. Examples of the aromatic hydrocarbon group include a group (aryl group) in which one hydrogen atom has been removed from the above-mentioned aromatic hydrocarbon ring. Specific preferred examples of the aromatic hydrocarbon group include a phenyl group, a naphthalene-1-yl group, and a naphthalene-2-yl group.

[0098] X b1The number of iodine atoms substituting the aromatic group as is preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less.

[0099] R b11 is preferably an iodine atom.

[0100] R b12 The hydrocarbon group as the alkyl group is preferably an alkyl group. The number of carbon atoms in the alkyl group is preferably 1 to 10, more preferably 1 to 5. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an isopropyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.

[0101] R b12 The number of carbon atoms in the alkoxy group as R is preferably 1 or more and 10 or less, and more preferably 1 or more and 5 or less. b12 Examples of the alkoxy group as the alkoxy group include a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, an isobutyloxy group, a sec-butyloxy group, and a tert-butyloxy group.

[0102] R b12 Examples of the substituent that the hydrocarbon group and alkoxy group may have include a fluorine atom.

[0103] R b12 As the group, a hydroxyl group is preferred.

[0104] q1 is preferably 1 or more and 3 or less, and 1 is more preferable. q2 is preferably 0 or 1, and more preferably 0.

[0105] R b13 , and R b14 Examples of the optionally substituted hydrocarbon group as the aryl group include an optionally substituted aryl group, an optionally substituted alkyl group, and an optionally substituted alkenyl group. R b13 , and Rb14 The aryl group as is preferably an unsubstituted aryl group having 6 to 20 carbon atoms, more preferably a phenyl group or a naphthyl group. R b13 , and R b14 The alkyl group preferably has 1 or more and 30 or less carbon atoms. R b13 , and R b14 The alkenyl group as the alkyl group preferably has 2 or more and 10 or less carbon atoms.

[0106] R b13 , and R b14 Examples of the substituent that the hydrocarbon group may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and a group represented by any one of the following formulas (ca-r-1) to (ca-r-7). [ka] (In the formula, R' 201 are each independently a hydrogen atom, an optionally substituted cyclic group, an optionally substituted alkyl group, or an optionally substituted alkenyl group.

[0107] Optionally substituted cyclic groups: The cyclic group, which may have a substituent, is preferably a cyclic hydrocarbon group or a heterocyclic group. The cyclic hydrocarbon group may be an aromatic hydrocarbon group or an alicyclic hydrocarbon group. The aliphatic hydrocarbon group and the alicyclic heterocyclic group may have one or more unsaturated bonds, and are preferably saturated aliphatic hydrocarbon groups and saturated alicyclic heterocyclic groups.

[0108] R' 201 The number of carbon atoms in the aromatic hydrocarbon group as is preferably 6 or more and 30 or less, more preferably 6 or more and 20 or less, even more preferably 6 or more and 15 or less, and particularly preferably 6 or more and 10 or less, but does not include the number of carbon atoms in the substituent. R' 201Specific examples of the aromatic hydrocarbon ring constituting the aromatic hydrocarbon group include a benzene ring, a fluorene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and a biphenyl ring. R' 201 Examples of the aromatic hydrocarbon group include groups in which one hydrogen atom has been removed from the above-mentioned aromatic hydrocarbon ring (e.g., aryl groups). Specific preferred examples of the aromatic hydrocarbon group include a phenyl group, a naphthalene-1-yl group, and a naphthalene-2-yl group.

[0109] R' 201 The alicyclic hydrocarbon group as the alkyl group preferably has 3 or more and 20 or less carbon atoms, and more preferably has 3 or more and 12 or less carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane. The polycycloalkane is preferably a polycycloalkane having 7 to 30 carbon atoms. The polycycloalkane is more preferably a polycycloalkane having a bridged ring polycyclic skeleton, such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; or a polycycloalkane having a fused ring polycyclic skeleton, such as a cyclic group having a steroid skeleton.

[0110] R' 201 The alicyclic hydrocarbon group as is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or a polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, particularly preferably an adamantyl group or a norbornyl group, and most preferably an adamantyl group.

[0111] R' 201The cyclic group as may be a heterocyclic group. The heterocyclic group may be an aliphatic heterocyclic group or an aromatic heterocyclic group. Specific examples of the heterocyclic group include a lactone-containing cyclic group, an -SO2- containing cyclic group, and a heterocyclic group represented by any one of the following formulae (r-hr-1) to (r-hr-16). In the formulae, * represents a bond.

[0112] A "lactone-containing cyclic group" is a cyclic group that contains a ring (lactone ring) containing -OC(=O)- in its ring skeleton. A group consisting of only a lactone ring is a monocyclic group. A group that has a lactone ring and another ring structure is a polycyclic group. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group. The term "-SO2-containing cyclic group" refers to a cyclic group containing a ring containing -SO2- in its ring skeleton, specifically a cyclic group in which the sulfur atom (S) in -SO2- forms part of the ring skeleton of the cyclic group. A group consisting only of a ring containing -SO2- is a monocyclic group. A group having an -SO2- ring and another ring structure is a polycyclic group. The -SO2-containing cyclic group may be a monocyclic group or a polycyclic group. The -SO2-containing cyclic group is particularly preferably a cyclic group containing -O-SO2- in its ring skeleton, i.e., a cyclic group containing a sultone ring in which -OS- in -O-SO2- forms part of the ring skeleton.

[0113] [ka]

[0114] R' 201 Examples of the substituent that the cyclic group may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (=O), and a nitro group. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as a substituent is preferably an alkoxy group having from 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, or a tert-butyloxy group, and still more preferably a methoxy group or an ethoxy group. Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Of these, a fluorine atom is preferred. Examples of halogenated alkyl groups as substituents include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms have been substituted with the above-mentioned halogen atoms.

[0115] Optionally substituted alkyl groups: R' 201 The alkyl group as may be a straight-chain alkyl group or a branched-chain alkyl group. The number of carbon atoms in the linear alkyl group is preferably from 1 to 20, more preferably from 1 to 15, and even more preferably from 1 to 10. Specific examples of the linear alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, an n-nonadecyl group, and an icosyl group. The number of carbon atoms in the branched alkyl group is preferably 3 to 20, more preferably 3 to 15, and even more preferably 3 to 10. Specific examples of the branched alkyl group include a 1-methylethyl group (isopropyl group), a 1-methylpropyl group (sec-butyl group), a 2-methylpropyl group (isobutyl group), a 1-methylbutyl group (sec-pentyl group), a 2-methylbutyl group, a 3-methylbutyl group (isopentyl group), a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0116] Optionally substituted alkenyl groups: R' 201 The alkenyl group as may be a linear alkenyl group or a branched alkenyl group. The number of carbon atoms in the alkenyl group is preferably 2 to 10, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of linear alkenyl groups include vinyl, 2-propenyl (allyl), 1-propenyl, 3-butenyl, 2-butenyl, and 1-butenyl. Examples of branched alkenyl groups include 1-methylvinyl, 1-methyl-2-propenyl, and 2-methyl-2-propenyl. The alkenyl group is preferably a linear alkenyl group, more preferably a vinyl group, a 2-propenyl group, or a 1-propenyl group, and even more preferably a vinyl group.

[0117] R' 201 Examples of the substituent that the alkyl group and alkenyl group may have include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (=O), a nitro group, an amino group, and the above-mentioned R' 201 Examples of such groups include cyclic groups such as:

[0118] R' 201 Examples of the optionally substituted cyclic group, optionally substituted alkyl group, and optionally substituted alkenyl group as mentioned above include, in addition to the groups mentioned above, tertiary alkyl ester-type acid-dissociable groups.

[0119] R' 201 is preferably a cyclic group which may have a substituent, specifically, a phenyl group, a naphthyl group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane, a lactone-containing cyclic group, an -SO2- containing cyclic group, etc.

[0120] R b13 , and R b14may be bonded to each other to form a ring. For example, they may be bonded to each other to form a ring together with the sulfur atom in the formula, or may be bonded to each other to form a fused ring together with the sulfur atom in the formula and the benzene ring. R b13 , and R b14 When R forms a condensed ring together with the sulfur atom and the benzene ring in the formula b13 , and R b14 is a heteroatom such as a sulfur atom, an oxygen atom, or a nitrogen atom, a carbonyl group, -SO-, -SO2-, -SO3-, -COO-, -CONH-, or -N(R N )-(the R N is an alkyl group having 1 to 5 carbon atoms. R b13 , and R b14 The ring formed by bonding is preferably a 3- to 10-membered ring, and more preferably a 5- to 7-membered ring. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthrene ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring.

[0121] In formula (b1-1), R b13 , and R b14 are each independently a phenyl group which may have a substituent, or a naphthyl group which may have a substituent, or R b13 , and R b14 are preferably bonded to each other to form a ring together with the sulfur atom in the formula.

[0122] Specific examples of the sulfonium cation represented by formula (b1-1) are shown below. [ka] [ka]

[0123] The sulfonium cation represented by formula (b1-1) is preferably a sulfonium cation represented by formula (b1-1a). [ka] (In formula (b1-1a), R b21 , and R b22 are each independently an iodine atom, a fluorine atom, a hydroxyl group, a hydrocarbon group which may have a substituent, or an alkoxy group which may have a substituent; q3 and q4 are each independently an integer of 0 to 5; R b11 , R b12 , q1, and q2 are R in formula (b1-1). b11 , R b12 , q1, and q2 are the same groups.

[0124] If q3 is an integer of 2 or more, multiple R b21 may be the same or different. When q4 is an integer of 2 or more, a plurality of R b22 may be the same or different.

[0125] R b21 , and R b22 The hydrocarbon group which may have a substituent as R b12 The hydrocarbon groups may have the same substituents as those of R. b21 , and R b22 The hydrocarbon group which may have a substituent as the alkyl group is preferably an alkyl group which may have a fluorine atom (fluorinated alkyl group).

[0126] R b21 , and R b22 The alkoxy group which may have a substituent as R b12 Examples of the alkoxy group include the same groups as the alkoxy group which may have a substituent as mentioned above.

[0127] R b21 , and R b22As the alkyl group, an iodine atom, a fluorine atom, a hydroxyl group, and a hydrocarbon group which may have a substituent are preferred, and an iodine atom, a fluorine atom, a hydroxyl group, and a fluorinated alkyl group are more preferred.

[0128] Each of q3 and q4 is preferably an integer of 0 or more and 3 or less, and more preferably 1 or 2.

[0129] (anion part) The anion moiety of the photoacid generator (B1) is not particularly limited and can be appropriately selected from anions known as the anion moiety of photoacid generators used in photosensitive compositions.

[0130] The anion moiety includes, for example, an anion represented by the following formula (b1-2). [ka] (In formula (b1-2), R b10 is an organic group having 1 to 40 carbon atoms.

[0131] R b10 Examples of the organic group as include a hydrocarbon group which may have a substituent, a divalent linking group containing an oxygen atom, and a combination thereof.

[0132] The anion represented by formula (b1-2) is preferably an anion represented by the following formula (b1-3): [ka] (In formula (b1-3), R b101 represents a cyclic group which may have a substituent, an alkyl group which may have a substituent, or an alkenyl group which may have a substituent, and Yb 0 is a divalent linking group or a single bond, and Vb 0 is a single bond, an alkylene group, or a fluorinated alkylene group, and R 0 is a hydrogen atom, a fluorinated alkyl group having from 1 to 5 carbon atoms, or a fluorine atom.

[0133] R b101 Optionally substituted cyclic groups as follows: The cyclic group may be a cyclic hydrocarbon group or a cyclic heterocyclic group. The cyclic group may be an alicyclic hydrocarbon group, an aromatic hydrocarbon group, an aliphatic heterocyclic group, an aromatic heterocyclic group, or a cyclic group in which two or more rings selected from these rings are condensed. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

[0134] R b101 The number of carbon atoms in the cyclic group as defined above is preferably from 3 to 30, more preferably from 5 to 30, even more preferably from 5 to 20, and particularly preferably from 6 to 18. The number of carbon atoms in the cyclic group does not include the number of carbon atoms of the substituent.

[0135] Examples of aromatic rings constituting the aromatic hydrocarbon group include a benzene ring, a fluorene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and a biphenyl ring. Examples of aromatic hydrocarbon groups include groups in which one hydrogen atom has been removed from the above-mentioned aromatic ring (aryl groups). Specific examples of aromatic hydrocarbon groups include phenyl, naphthalene-1-yl, and naphthalene-2-yl groups.

[0136] R b101 The number of carbon atoms in the alicyclic hydrocarbon group as is preferably 3 or more and 30 or less, more preferably 3 or more and 20 or less, and even more preferably 3 or more and 12 or less. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms. Specific examples of monocycloalkanes include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane. The polycycloalkane is preferably a polycycloalkane having 7 to 30 carbon atoms. The polycycloalkane is more preferably a polycycloalkane having a bridged ring polycyclic skeleton, such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; or a polycycloalkane having a fused ring polycyclic skeleton, such as a cyclic group having a steroid skeleton.

[0137] R b101 The alicyclic hydrocarbon group as is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or a polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, further preferably an adamantyl group or a norbornyl group, and particularly preferably an adamantyl group.

[0138] R b101 The cyclic group as may be a heterocyclic group. The heterocyclic group may be an aromatic heterocyclic group or an aliphatic heterocyclic group. Specific examples include lactone-containing cyclic groups, -SO2- containing cyclic groups, and heterocyclic groups represented by the above chemical formulas (r-hr-1) to (r-hr-16).

[0139] R b101 Examples of the substituent that the cyclic group as (I) may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (═O), a nitro group, and a cyclic group that may have a substituent. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as a substituent is preferably an alkoxy group having from 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, or a tert-butyloxy group, and still more preferably a methoxy group or an ethoxy group. Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred. Examples of the halogenated alkyl group as a substituent include groups in which some or all of the hydrogen atoms of an alkyl group having from 1 to 5 carbon atoms have been substituted with the above-mentioned halogen atoms. As the alkyl group having from 1 to 5 carbon atoms, the groups listed as specific examples of the alkoxy group as a substituent are preferred. Examples of the cyclic group which may have a substituent as a substituent include R b101 Examples of the cyclic group include the same groups as the cyclic group which may have a substituent as mentioned above.

[0140] R b101 The cyclic group as defined above may be a fused ring group consisting of a fused ring formed by condensing an aliphatic hydrocarbon ring with an aromatic hydrocarbon ring. Examples of the fused ring include a ring formed by condensing one or more aromatic rings to a polycycloalkane having a bridged ring polycyclic skeleton. Specific examples of the bridged ring polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused ring group is preferably a group containing a fused ring formed by condensing two or three aromatic rings to a bicycloalkane, and more preferably a group containing a fused ring formed by condensing two or three aromatic rings to a bicyclo[2.2.2]octane. R b101 Specific examples of the fused cyclic group as include groups represented by the following formulae (r-br-1) to (r-br-2).

[0141] In the formula, * represents Yb in formula (b1-3). 0 represents a bond bonded to

[0142] [ka]

[0143] R b101 Examples of the substituent that the fused cyclic group as (I) may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (═O), a nitro group, an aromatic hydrocarbon group, and an alicyclic hydrocarbon group. The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent of the above fused cyclic group are the same as those described above in R 101 Examples of the substituents include the same groups as those exemplified as the substituents of the cyclic group.

[0144] R b101 An alkyl group which may have a substituent as follows: R b101 The alkyl group may be a linear alkyl group or a branched alkyl group. The number of carbon atoms in the linear alkyl group is preferably from 1 to 20, more preferably from 1 to 15, and even more preferably from 1 to 10. Specific examples of the linear alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, an n-nonadecyl group, and an n-icosyl group. The number of carbon atoms in the branched alkyl group is preferably 3 to 20, more preferably 3 to 15, and even more preferably 3 to 10. Specific examples of the branched alkyl group include a 1-methylethyl group (isopropyl group), a 1-methylpropyl group (sec-butyl group), a 2-methylpropyl group (isobutyl group), a 1-methylbutyl group (sec-pentyl group), a 2-methylbutyl group, a 3-methylbutyl group (isopentyl group), a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0145] R b101 An alkenyl group which may have a substituent as follows: R b101 The alkenyl group as may be a linear alkenyl group or a branched alkenyl group. The number of carbon atoms in the alkenyl group is preferably 2 to 10, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of linear alkenyl groups include vinyl, 2-propenyl (allyl), 1-propenyl, 3-butenyl, 2-butenyl, and 1-butenyl groups. Examples of branched alkenyl groups include 1-methylvinyl, 1-methyl-2-propenyl, and 2-methyl-2-propenyl groups. The chain alkenyl group is preferably a linear alkenyl group, more preferably a vinyl group or a 2-propenyl group, and even more preferably a vinyl group.

[0146] R b101 Examples of the substituent that the alkyl group or alkenyl group may have include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (=O), a nitro group, an amino group, and the above-mentioned R b101 Examples of such groups include cyclic groups such as:

[0147] R b101 is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. Specific examples of preferred cyclic groups include a phenyl group, a naphthalene-1-yl group, a naphthalene-2-yl group, a group in which one hydrogen atom has been removed from a polycycloalkane, a lactone-containing cyclic group, an -SO2- containing cyclic group, and a fused cyclic group containing a fused ring in which an aliphatic hydrocarbon ring and an aromatic ring are fused.

[0148] Yb 0 is a divalent linking group or a single bond. Yb 0The divalent linking group as (I) is preferably a divalent linking group containing an oxygen atom. The divalent linking group containing an oxygen atom may contain an atom other than an oxygen atom. Examples of the atom other than an oxygen atom include a carbon atom, a hydrogen atom, a sulfur atom, and a nitrogen atom. Examples of divalent linking groups containing an oxygen atom include non-hydrocarbon oxygen-containing linking groups such as an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), an oxycarbonyl group (-O-C(=O)-), an amide bond (-C(=O)-NH-), a carbonyl group (-C(=O)-), and a carbonate bond (-O-C(=O)-O-); and combinations of such non-hydrocarbon oxygen-containing linking groups with alkylene groups. A sulfonyl group (-SO-) may be further linked to this combination. Examples of such divalent linking groups containing an oxygen atom include linking groups represented by the following formulae (y-al-1) to (y-al-7).

[0149] [ka] (In the formula, V' 101 is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' 102 is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.

[0150] V' 102 The divalent saturated hydrocarbon group as is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

[0151] V' 101 , and V' 102 The alkylene group as may be a linear alkylene group or a branched alkylene group, and is preferably a linear alkylene group. V' 101 , and V' 102Specific examples of the alkylene group as the alkylene group include a methylene group [-CH2-]; alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; an ethylene group [-CH2CH2-]; -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, and -CH(CH2CH3)CH2- alkylethylene groups such as alkylethylene groups, trimethylene groups (n-propylene groups) [-CHCHCH-]; alkyltrimethylene groups such as -CH(CH)CHCH- and -CHCH(CH)CH-; tetramethylene groups [-CHCHCHCHCH-]; alkyltetramethylene groups such as -CH(CH)CHCHCHCH- and -CHCH(CH)CHCH-; and pentamethylene groups [-CHCHCHCHCHCH-]. Also, V' 101 , or V' 102 Some of the methylene groups in the alkylene group in the above may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably a divalent group in which one hydrogen atom has been removed from an alicyclic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group), and more preferably a cyclohexylene group, a 1,5-adamantylene group, or a 2,6-adamantylene group.

[0152] Yb 0 As the linking group, a divalent linking group containing an ester bond and a divalent linking group containing an ether bond are preferred, and the linking groups represented by the above formulas (y-al-1) to (y-al-5) are more preferred.

[0153] Vb 0 is a single bond, an alkylene group, or a fluorinated alkylene group. 0 The alkylene group and fluorinated alkylene group represented by Vb preferably have 1 or more and 4 or less carbon atoms. 0 Examples of the fluorinated alkylene group as Vb 0Examples of the alkylene group include a group in which some or all of the hydrogen atoms of the alkylene group have been substituted with fluorine atoms. 0 is preferably a linear fluorinated alkylene group having 1 to 4 carbon atoms, or a single bond.

[0154] R 0 is a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorine atom. 0 is preferably a hydrogen atom, a perfluoroalkyl group having 1 to 5 carbon atoms, or a fluorine atom, and more preferably a fluorine atom.

[0155] The anion represented by formula (b1-3) is preferably an anion represented by the following formula (b1-4): [ka] (In formula (b1-4), R b31 represents a cyclic group which may have a substituent, and Yb 31 is a divalent linking group, and R b32 represents a cyclic group which may have a substituent, and Yb 32 represents a divalent linking group, n31 represents 0 or 1, and Vb 0 , and R 0 is Vb in formula (b1-3) 0 , and R 0 It is the same group as

[0156] R b31 The optionally substituted cyclic group as R b101 The cyclic group R may have the same substituent as the cyclic group R. b31 The cyclic group which may have a substituent as the substituent is preferably a phenyl group which may have a substituent, or a fused cyclic group containing a fused ring in which an aliphatic hydrocarbon ring which may have a substituent and an aromatic ring are fused. The substituent is preferably a halogen atom, and more preferably an iodine atom.

[0157] R b32 The optionally substituted cyclic group as R b101The cyclic group R may have the same substituent as the cyclic group R. b32 The cyclic group which may have a substituent as the substituent is preferably a phenyl group which may have a substituent, or a fused cyclic group containing a fused ring in which an aliphatic hydrocarbon ring which may have a substituent and an aromatic ring are fused. The substituent is preferably a halogen atom, and more preferably an iodine atom.

[0158] Yb 31 As the divalent linking group, Yb 0 The divalent linking group Yb may be the same as the divalent linking group Yb. 31 As the divalent linking group as , a divalent linking group containing an ester bond and a divalent linking group containing an ether bond are preferred, and an ester bond is more preferred.

[0159] Yb 32 As the divalent linking group, Yb 0 The divalent linking group Yb may be the same as the divalent linking group Yb. 32 As the divalent linking group as , a divalent linking group containing an ester bond and a divalent linking group containing an ether bond are preferred, and an ester bond is more preferred.

[0160] n31 is preferably 1.

[0161] Specific examples of the anion moiety of the photoacid generator (B1) are shown below. [ka]

[0162] The content of the photoacid generator (B1) is preferably 5 to 80 parts by mass, more preferably 10 to 60 parts by mass, and even more preferably 15 to 50 parts by mass, per 100 parts by mass of the silicon-containing polymer (A). When the content of the photoacid generator (B1) is within the above preferred range, the effects of the present invention are easily achieved.

[0163] [Other photoacid generators] The photoacid generator (B) may contain a photoacid generator other than the photoacid generator (B1). The other photoacid generator is not particularly limited, and any photoacid generator that has been proposed as a photoacid generator for a photosensitive composition can be used. Examples of such photoacid generators include various types of photoacid generators, such as onium salt-based acid generators such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generators, diazomethane-based acid generators such as bisalkyl or bisaryl sulfonyl diazomethanes and poly(bissulfonyl) diazomethanes, nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

[0164] The mass ratio of the photoacid generator (B1) to 100% by mass of the photoacid generator (B) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, particularly preferably 95% by mass or more, and may be 100% by mass.

[0165] The content of the photoacid generator (B) is preferably 5 to 80 parts by mass, more preferably 10 to 60 parts by mass, and even more preferably 15 to 50 parts by mass, per 100 parts by mass of the silicon-containing polymer (A). When the content of the photoacid generator (B) is within the above preferred range, the desired effects are likely to be obtained.

[0166] <Crosslinking agent (C)> Examples of the crosslinking agent (C) include melamine-based crosslinking agents, urea-based crosslinking agents, alkylene urea-based crosslinking agents, glycoluril-based crosslinking agents, phenol-based crosslinking agents, and epoxy-based crosslinking agents. In the following description, "lower" means having 1 to 5 carbon atoms.

[0167] Examples of the melamine-based crosslinking agent include compounds in which some or all of the hydrogen atoms in the amino groups of melamine have been substituted with hydroxymethyl groups, and compounds in which some or all of the hydrogen atoms in the amino groups of melamine have been substituted with lower alkoxymethyl groups. Specifically, hexamethoxymethylmelamine, hexaethoxymethylmelamine, hexapropoxymethylmelamine, and hexabutoxybutylmelamine are preferred, with hexamethoxymethylmelamine being more preferred.

[0168] Examples of the urea-based crosslinking agent include a compound in which some or all of the hydrogen atoms in the amino groups of urea are substituted with hydroxymethyl groups, and a compound in which some or all of the hydrogen atoms in the amino groups of urea are substituted with lower alkoxymethyl groups. Specifically, bismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, bisbutoxymethylurea, etc. are preferred, and bismethoxymethylurea is more preferred.

[0169] The alkylene urea crosslinking agent may be a compound represented by the following formula (CA-1).

[0170] [ka] (In formula (CA-1), Rc 1 and Rc 2 Rc is independently a hydroxyl group or a lower alkoxy group. 3 and Rc 4 are each independently a hydrogen atom, a hydroxyl group, or a lower alkoxy group, and vc is an integer of 0 or more and 2 or less.

[0171] Rc 1 and Rc 2 When Rc is a lower alkoxy group, the lower alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms. The lower alkoxy group may be a linear alkoxy group or a branched alkoxy group. 1 and Rc 2and may be the same or different from each other, and are more preferably the same. Rc 3 and Rc 4 When Rc is a lower alkoxy group, the lower alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms. The lower alkoxy group may be a linear alkoxy group or a branched alkoxy group. 3 and Rc 4 and may be the same or different from each other, and are more preferably the same. vc is preferably 0 or 1. As the alkylene urea crosslinking agent, a compound in which vc is 0 (ethylene urea crosslinking agent) and / or a compound in which vc is 1 (propylene urea crosslinking agent) are particularly preferred.

[0172] Specific examples of the alkylene urea-based crosslinking agent include ethylene urea-based crosslinking agents such as monohydroxymethylated ethylene urea, dihydroxymethylated ethylene urea, monomethoxymethylated ethylene urea, dimethoxymethylated ethylene urea, monoethoxymethylated ethylene urea, diethoxymethylated ethylene urea, monopropoxymethylated ethylene urea, dipropoxymethylated ethylene urea, monobutoxymethylated ethylene urea, and dibutoxymethylated ethylene urea; propylene urea-based crosslinking agents such as monoethoxymethylated propylene urea, monomethoxymethylated propylene urea, dimethoxymethylated propylene urea, monoethoxymethylated propylene urea, diethoxymethylated propylene urea, monopropoxymethylated propylene urea, dipropoxymethylated propylene urea, monodibutoxymethylated propylene urea, and dibutoxymethylated propylene urea; 1,3-di(methoxymethyl)-4,5-dihydroxy-2-imidazolidinone, 1,3-di(methoxymethyl)-4,5-dimethoxy-2-imidazolidinone, and the like.

[0173] Examples of glycoluril crosslinking agents include glycoluril derivatives in which the N-position is substituted with one or both of a hydroxyalkyl group and an alkoxyalkyl group having from 1 to 4 carbon atoms. The glycoluril derivatives can be obtained by condensation reaction of glycoluril with formalin and then by reacting the product with a lower alcohol. Specific examples of glycoluril-based crosslinking agents include hydroxymethylated glycolurils such as monohydroxymethylated glycoluril, dihydroxymethylated glycoluril, trihydroxymethylated glycoluril, and tetrahydroxymethylated glycoluril; methoxymethylated glycolurils such as monomethoxymethylated glycoluril, dimethoxymethylated glycoluril, trimethoxymethylated glycoluril, and tetramethoxymethylated glycoluril; ethoxymethylated glycolurils such as monoethoxymethylated glycoluril, diethoxymethylated glycoluril, triethoxymethylated glycoluril, and tetraethoxymethylated glycoluril; propoxymethylated glycolurils such as monopropoxymethylated glycoluril, dipropoxymethylated glycoluril, tripropoxymethylated glycoluril, and tetrapropoxymethylated glycoluril; and butoxymethylated glycolurils such as monobutoxymethylated glycoluril, dibutoxymethylated glycoluril, tributoxymethylated glycoluril, and tetrabutoxymethylated glycoluril.

[0174] The phenol-based crosslinking agent is not particularly limited as long as it is a compound having multiple phenol nucleus structures in the same molecule, and the adjacent positions to the bonding position of the phenol-based hydroxyl group on the aromatic ring are substituted with methylol groups and / or alkoxyalkyl groups. The presence of multiple phenol nucleus structures improves crosslinking reactivity. The number of phenolic nucleus structures is preferably 2 or more and 5 or less, more preferably 2 or more and 4 or less, and even more preferably 2 or 3.

[0175] The epoxy-based crosslinking agent is not particularly limited as long as it has an epoxy group, and can be arbitrarily selected from known epoxy-based crosslinking agents. As the epoxy-based crosslinking agent, a crosslinking agent having two or more epoxy groups is preferred in terms of good crosslinking reactivity. The number of epoxy groups in one molecule of the epoxy-based crosslinking agent is preferably 2 or more, more preferably 2 or more and 4 or less, and most preferably 2.

[0176] The crosslinking agent (C) is preferably a crosslinking agent (C1) having a methylol group and / or an alkoxyalkyl group, and among them, a crosslinking agent selected from the group consisting of glycoluril crosslinking agents and phenolic crosslinking agents is more preferred. Suitable examples of such crosslinking agents include compounds represented by the following formula (c1-1): [ka] (In formula (c1-1), s1 is an integer of 1 or more and 10 or less. R C0 is a glycoluril structure or a polynuclear phenol structure. C1 is an alkyl group having 1 to 5 carbon atoms, or a hydrogen atom.

[0177] s1 is an integer of 1 or more and 10 or less, preferably an integer of 2 or more and 10 or less, and more preferably an integer of 4 or more and 9 or less. R C0 The glycoluril structure in C0 -1) refers to the structure represented by

[0178] [ka]

[0179] R C0 The polynuclear phenol structure as defined above is a structure containing two or more structures selected from the group consisting of a phenol structure and a naphthol structure.

[0180] Specific examples of suitable crosslinking agents (C) include the following compounds: [ka]

[0181] The crosslinking agent (C) may be used alone or in combination of two or more kinds. The content of the crosslinking agent (C) is preferably 1 part by mass or more and 50 parts by mass or less, more preferably 3 parts by mass or more and 40 parts by mass or less, even more preferably 5 parts by mass or more and 30 parts by mass or less, and particularly preferably 5 parts by mass or more and 25 parts by mass or less, per 100 parts by mass of the silicon-containing polymer (A). When the amount of the crosslinking agent (C) used is at least the lower limit of the above-mentioned preferred range, crosslinking proceeds sufficiently, making it easy to obtain dissolution contrast, and the photosensitive composition has excellent resolution performance and lithography properties, and a good cured film with little swelling is easily formed. When the amount of the crosslinking agent (C) used is equal to or less than the upper limit of the above preferred range, the storage stability of the photosensitive composition is good, and deterioration of sensitivity over time is easily suppressed.

[0182] <Base component (D) that controls the diffusion of acid generated by exposure> The photosensitive composition preferably contains a base component (D) that controls the diffusion of the acid generated by exposure. The base component (D) acts as a quencher (acid diffusion controller) that traps the acid generated by exposure in the photosensitive composition. Examples of the base component (D) include a photodegradable base (D1) that decomposes upon exposure and loses its acid diffusion controllability, and a nitrogen-containing organic compound (D2) that does not fall under the category of a photodegradable base (D1). From the viewpoints of increasing sensitivity, reducing roughness, and suppressing the occurrence of coating defects, the base component (D) is preferably a photodegradable base (D1).

[0183] Use of a photosensitive composition containing a photodegradable base (D1) can further improve the contrast between exposed and unexposed areas of a coating film made of the photosensitive composition when forming a patterned cured film. The photodegradable base (D1) is not particularly limited as long as it is a base that decomposes upon exposure to light and loses its acid diffusion controllability, and is preferably a compound represented by the following formula (d1-1) (hereinafter referred to as "component (d1-1)"): The component (d1-1) decomposes and loses its acid diffusion control property (basicity) in the exposed areas of the coating film made of the photosensitive composition, and therefore does not act as a quencher, but acts as a quencher in the unexposed areas of the coating film.

[0184] [ka] (In the formula, Rd 1 is a monovalent organic group; m is an integer of 1 or more; M m+ are each independently an m-valent organic cation.

[0185] {(d1-1) component} Anion part In formula (d1-1), Rd 1 is a monovalent organic group. The monovalent organic group is not particularly limited as long as the component (d1-1) functions well as a quencher. Preferred monovalent organic groups are cyclic groups which may have a substituent, alkyl groups which may have a substituent, and alkenyl groups which may have a substituent. These groups each have the same meaning as R' 201 The same groups as those shown below can be mentioned. Road 1 As the alkyl group, an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, and an alkyl group which may have a substituent are preferred, and an aromatic hydrocarbon group which may have a substituent is more preferred. Substituents that these groups may have include a hydroxyl group, an oxo group (=O), an alkyl group, an aryl group, a fluorine atom, a bromine atom, an iodine atom, a fluorinated alkyl group, and a lactone-containing cyclic group.

[0186] Road 1As the monovalent organic group, a group in which a divalent group containing an ether bond or an ester bond is bonded to a cyclic group which may have a substituent, an alkyl group which may have a substituent, or an alkenyl group which may have a substituent is also preferred. As the divalent group containing an ether bond or an ester bond, the linking groups represented by the above formulas (y-al-1) to (y-al-5) are preferred. In this case, suitable examples of the cyclic group bonded to the linking group include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and other ring structures). These cyclic groups may have the above-mentioned substituents. As the cyclic group bonded to the above linking group, groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, bicyclooctane, tricyclodecane, or tetracyclododecane are also preferred. The alkyl group bonded to the linking group is preferably an alkyl group having from 1 to 10 carbon atoms. Specific examples include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; and branched alkyl groups such as 1-methylethyl (isopropyl), 1-methylpropyl (sec-butyl), 2-methylpropyl (isobutyl), 1-methylbutyl (sec-pentyl), 2-methylbutyl, 3-methylbutyl (isopentyl), 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl groups.

[0187] When the alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the number of carbon atoms in the fluorinated alkyl group is preferably from 1 to 11, more preferably from 1 to 8, and even more preferably from 1 to 4. The fluorinated alkyl group may contain atoms other than fluorine atoms.

[0188] Preferred examples of the anion moiety of the component (d1-1) are shown below.

[0189] [ka]

[0190] [ka]

[0191] Cation part In formula (d1-1), M m+ is an m-valent organic cation. M m+ Suitable examples of the organic cation represented by the formula (b1-1) include the same cations as the sulfonium cation represented by the formula (b1-1) above.

[0192] Also, M m+ As the organic cation represented by the formula (d1-1a), a cation represented by the following formula (d1-1a) is also preferred. [ka] (In formula (d1-1a), R b1 is an aryl group having a fluorine atom or an aryl group having a fluorinated alkyl group. b2 , and R b3 R are each independently an aryl group which may have a substituent, an alkyl group which may have a substituent, or an alkenyl group which may have a substituent. b1 ~R b3 Two of may be bonded to each other to form a ring together with the sulfur atom in the formula.

[0193] In formula (d1-1a), R b1 is an aryl group having a fluorine atom or an aryl group having a fluorinated alkyl group. R b1The number of carbon atoms in the aryl group as the aryl group is preferably 5 or more and 30 or less, more preferably 5 or more and 20 or less, even more preferably 6 or more and 15 or less, and particularly preferably 6 or more and 10 or less. However, the number of carbon atoms in the aryl group does not include the number of carbon atoms in the substituent. R b1 Specifically, the aryl group as is preferably a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, or a biphenyl group, more preferably a phenyl group or a naphthyl group, and even more preferably a phenyl group.

[0194] R b1 Specific examples of the fluorinated alkyl group contained in the aryl group as above include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 12 carbon atoms have been substituted with fluorine atoms. The fluorinated alkyl group may be a linear fluorinated alkyl group or a branched fluorinated alkyl group. Specific examples of linear fluorinated alkyl groups having from 1 to 12 carbon atoms include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, and n-dodecyl groups in which some or all of the hydrogen atoms have been substituted with fluorine atoms. Specific examples of branched fluorinated alkyl groups having from 1 to 12 carbon atoms include 1-methylethyl (isopropyl), 1,1-dimethylethyl (tert-butyl), 1-methylpropyl (sec-butyl), 2-methylpropyl (isobutyl), 1-methylbutyl (sec-pentyl), 2-methylbutyl, 3-methylbutyl (isopentyl), 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl groups in which some or all of the hydrogen atoms have been substituted with fluorine atoms.

[0195] R b1The fluorinated alkyl group carried by the aryl group as the aryl group is preferably a group in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms have been substituted with fluorine atoms, more preferably a group in which some or all of the hydrogen atoms of an alkyl group having 1 to 3 carbon atoms have been substituted with fluorine atoms, and even more preferably a trifluoromethyl group.

[0196] R b1 The aryl group as the substituent may have a substituent other than a fluorine atom or a fluorinated alkyl group. The substituent may be an alkyl group, a halogen atom other than a fluorine atom, a halogenated alkyl group other than a fluorinated alkyl group, an oxo group (=O), a cyano group, an amino group, a group represented by each of the above formulas (ca-r-1) to (ca-r-7), -SO2-R b0 Examples include monovalent groups represented by R b0 represents a linear alkyl group which may have a substituent, a branched alkyl group which may have a substituent, an alicyclic hydrocarbon group which may have a substituent, or an aromatic hydrocarbon group which may have a substituent.

[0197] R b0 Examples of the linear alkyl group and branched alkyl group as aryl include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, and a neopentyl group. Of these, a methyl group and an ethyl group are preferred, and a methyl group is more preferred. R b0 Examples of the substituent that the linear alkyl group and branched alkyl group may have include a halogen atom, a halogenated alkyl group having from 1 to 5 carbon atoms, an alkoxy group having from 1 to 5 carbon atoms, a hydroxy group, an oxo group (═O), and a carboxy group. R b0The number of carbon atoms in the alicyclic hydrocarbon group as the cycloaliphatic hydrocarbon group is preferably 3 to 20, more preferably 3 to 12. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms. Specific examples of monocycloalkanes include cyclobutane, cyclopentane, and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane. The polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms. Specific examples of polycycloalkanes include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. R b0 Examples of the aromatic hydrocarbon group as the aromatic hydrocarbon group include groups in which one hydrogen atom has been removed from an aromatic hydrocarbon ring such as a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a biphenyl ring, or a fluorene ring.

[0198] R b0 Examples of the substituent that the alicyclic hydrocarbon group or aromatic hydrocarbon group may have include -R P1 , -R P2 -OR P1 , -R P2 -CO-R P1 , -R P2 -CO-OR P1 , -R P2 -O-CO-R P1 , -R P2 -OH, -R P2 -CN and -R P2 -COOH and the like. where R P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent alicyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. P2is a single bond, a divalent chain saturated hydrocarbon group having from 1 to 10 carbon atoms, a divalent alicyclic saturated hydrocarbon group having from 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having from 6 to 30 carbon atoms. P1 , and R P2 Some or all of the hydrogen atoms in the chain saturated hydrocarbon group, the alicyclic saturated hydrocarbon group, and the aromatic hydrocarbon group may be substituted with fluorine atoms. The alicyclic hydrocarbon group may have one or more of the above-mentioned substituents alone, or may have one or more of each of multiple types of the above-mentioned substituents. Examples of monovalent chain-like saturated hydrocarbon groups (alkyl groups) having 1 to 10 carbon atoms include methyl groups, ethyl groups, n-propyl groups, n-butyl groups, n-pentyl groups, n-hexyl groups, n-heptyl groups, n-octyl groups, and n-decyl groups. Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, and a cyclododecyl group; and polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.02,6]decanyl group, a tricyclo[3.3.1.13,7]decanyl group, a tetracyclo[6.2.1.13,6.02,7]dodecanyl group, and an adamantyl group. Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include groups in which one hydrogen atom has been removed from an aromatic hydrocarbon ring such as a benzene ring, a biphenyl ring, a fluorene ring, a naphthalene ring, an anthracene ring, or a phenanthrene ring.

[0199] R b2 , and R b3 are each independently an aryl group which may have a substituent, an alkyl group which may have a substituent, or an alkenyl group which may have a substituent. R b2 , and R b3 The aryl group as R b1 The same groups as the aryl group as Rb2 , and R b3 The aryl group as is preferably a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, or a biphenyl group, more preferably a phenyl group or a naphthyl group, and even more preferably a phenyl group.

[0200] R b2 , and R b3 The alkyl group as the alkyl group is preferably an alkyl group having 1 to 30 carbon atoms. R b2 , and R b3 The alkenyl group in is preferably an alkenyl group having 2 or more and 10 or less carbon atoms.

[0201] R b2 , and R b3 Examples of the substituent that may be possessed by include an alkyl group, a halogen atom, a halogenated alkyl group, an oxo group (=O), a cyano group, an amino group, an aryl group, and groups represented by the above formulas (ca-r-1) to (ca-r-7), respectively.

[0202] R b2 , and R b3 is preferably an aryl group which may have a substituent. When the aryl group has a substituent, the substituent may be a fluorine atom, an iodine atom, a fluorinated alkyl group, or the above-mentioned —SO—R b0 A monovalent group represented by the formula (I) is preferred, and a fluorine atom, an iodine atom, a fluorinated alkyl group, and a methanesulfonyl group (mesyl group) are more preferred. b2 , and R b3 Particularly preferred are an unsubstituted aryl group, an aryl group having a fluorine atom, an aryl group having a fluorinated alkyl group, and an aryl group having a methanesulfonyl group (mesyl group).

[0203] R b1 ~R b3 Two of R may be bonded to each other to form a ring together with the sulfur atom in the formula. b1 ~R b3When two of the groups bond to each other to form a ring together with the sulfur atom in the formula, R b1 ~R b3 Two of them are heteroatoms such as sulfur, oxygen, and nitrogen atoms, or -SO-, -SO2-, -SO3-, -C(=O)-, -COO-, -CONH-, or -N(R N )-(R N is an alkyl group having 1 to 5 carbon atoms.) As for the ring formed, it is preferable that one ring containing a sulfur atom in its ring skeleton in the formula is a ring having 3 to 10 members, including the sulfur atom, and it is particularly preferable that it is a ring having 5 to 7 members. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring. R b1 and R b2 or R b3 and bond to each other to form a ring together with the sulfur atom in the formula, the ring structure formed only needs to have a fluorine atom or a fluorinated alkyl group, and a hydrogen atom of the structure derived from an aryl group (for example, a benzene ring structure) does not necessarily have to be substituted with a fluorine atom or a fluorinated alkyl group.

[0204] Preferred specific examples of the cation represented by formula (d1-1a) are shown below. [ka]

[0205] When the photosensitive composition contains a photodegradable base (D1), the content of the photodegradable base (D1) in the photosensitive composition is preferably 10 parts by mass or more, more preferably 15 parts by mass or more and 70 parts by mass or less, and even more preferably 20 parts by mass or more and 60 parts by mass or less, per 100 parts by mass of the silicon-containing polymer (A). When the content of the photodegradable base (D1) is equal to or greater than the lower limit of the above-mentioned preferred range, the photosensitive composition has particularly good lithography properties and is likely to form a patterned cured film with a good shape. When the content of the photodegradable base (D1) is equal to or less than the upper limit of the above-mentioned preferred range, the photosensitive composition has good sensitivity and excellent throughput.

[0206] The content of the (d1-1) component in the entire base component (D) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and may be 100% by mass.

[0207] Regarding component (D2) The component (D) may contain a nitrogen-containing organic compound component (D2) that does not fall under the category of the above-mentioned photodegradable base (D1). The nitrogen-containing organic compound component (D2) is not particularly limited as long as it acts as an acid diffusion controller and does not fall under the category of the photodegradable base (D1), and may be arbitrarily selected from known nitrogen-containing organic compounds. The nitrogen-containing organic compound component (D2) is preferably an aliphatic amine, more preferably a secondary aliphatic amine or a tertiary aliphatic amine. The aliphatic amine is an amine having one or more aliphatic groups, and the number of carbon atoms in the aliphatic group contained in the aliphatic amine is preferably 1 or more and 12 or less. Aliphatic amines include alkylamines in which at least one hydrogen atom of ammonia NH3 is substituted with an alkyl group having 12 or less carbon atoms, alkanolamines in which at least one hydrogen atom of ammonia NH3 is substituted with a hydroxyalkyl group having 1 to 12 carbon atoms, and cyclic amines. Specific examples of alkylamines and alkanolamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, and di-n-octylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkanolamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having an alkyl group having 5 to 10 carbon atoms are preferred, and tri-n-pentylamine and tri-n-octylamine are more preferred.

[0208] Examples of cyclic amines include heterocyclic compounds containing a nitrogen atom as a heteroatom. The heterocyclic compounds may be monocyclic compounds (aliphatic monocyclic amines) or polycyclic compounds (aliphatic polycyclic amines). Specific examples of the aliphatic monocyclic amine include piperidine and piperazine. The aliphatic polycyclic amine is preferably an amine having 6 to 10 carbon atoms, specifically 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5.4.0]-7-undecene, hexamethylenetetramine, and 1,4-diazabicyclo[2.2.2]octane.

[0209] Other aliphatic amines include dicyclohexylamine, tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxyethoxymethoxy)ethyl}amine, tris{2-(1-methoxyethoxy)ethyl}amine, tris{2-(1-ethoxyethoxy)ethyl}amine, tris{2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-(2-hydroxyethoxy)ethoxy}ethyl]amine, and triethanolamine triacetate, with triethanolamine triacetate being preferred.

[0210] As the nitrogen-containing organic compound component (D2), an amine having an aromatic group may be used. Examples of amines having an aromatic group include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole, imidazole derivatives, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, and 2,6-di-tert-butylpyridine.

[0211] The nitrogen-containing organic compound component (D2) may be used alone or in combination of two or more. When the photosensitive composition contains a nitrogen-containing organic compound (D2), the content of the nitrogen-containing organic compound (D2) is usually in the range of 0.01 to 5 parts by mass per 100 parts by mass of the silicon-containing polymer (A). By using this range, the patterned cured film has a good pattern shape, and the storage stability of the photosensitive composition is improved.

[0212] <At least one compound (E) selected from the group consisting of organic carboxylic acids, phosphorus oxoacids and derivatives thereof> The photosensitive composition may contain, as an optional component, at least one compound (E) selected from the group consisting of organic carboxylic acids, and phosphorus oxoacids and derivatives thereof, for the purposes of preventing a decrease in sensitivity, forming a patterned cured film with a good pattern shape, and improving storage stability. Preferred organic carboxylic acids include, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid. As the phosphorus oxoacid, phosphoric acid, phosphonic acid, phosphinic acid, etc. are preferred, and phosphonic acid is more preferred. Derivatives of phosphorus oxoacids include, for example, ester compounds in which the hydrogen atoms of the oxoacids are substituted with hydrocarbon groups, such as alkyl groups having 1 to 5 carbon atoms and aryl groups having 6 to 15 carbon atoms. Examples of the derivatives of phosphoric acid include phosphoric acid esters such as di-n-butyl phosphoric acid ester and diphenyl phosphoric acid ester. Examples of the derivatives of phosphonic acid include phosphonic acid esters such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, and dibenzyl phosphonate. Examples of the derivatives of phosphinic acid include phosphinic acid esters and phenylphosphinic acid. The compound (E) may be used alone or in combination of two or more kinds. When the photosensitive composition contains the compound (E), the content of the compound (E) is generally in the range of 0.01 to 10 parts by mass per 100 parts by mass of the silicon-containing polymer (A).

[0213] <Fluorine Additives (F)> The photosensitive composition may contain a fluorine additive (F) as a hydrophobic resin. The fluorine additive (F) is used to impart water repellency to the cured film formed using the photosensitive composition. When the fluorine additive (F) is used in the photosensitive composition as a resin separate from the silicon-containing polymer (A), the lithography properties are improved. As the fluorine additive (F), for example, fluorine-containing polymer compounds described in JP-A Nos. 2010-002870, 2010-032994, 2010-277043, 2011-13569, and 2011-128226 can be used. More specifically, the fluorine additive (F) may be a polymer having a structural unit (f1) represented by the following formula (f1-1). This polymer is preferably a polymer (homopolymer) consisting solely of the structural unit (f1) represented by the following formula (f1-1); a copolymer of the structural unit (f1) and a structural unit containing an acid-decomposable group whose polarity increases upon the action of acid; or a copolymer of a structural unit containing an acid-decomposable group whose polarity increases upon the action of acid, the structural unit (f1), and a structural unit derived from acrylic acid or methacrylic acid. Here, the structural unit containing an acid-decomposable group whose polarity increases upon the action of acid that is copolymerized with the structural unit (f1) is preferably a structural unit derived from 1-ethyl-1-cyclooctyl(meth)acrylate or a structural unit derived from 1-methyl-1-adamantyl(meth)acrylate.

[0214] [ka] In formula (f1-1), R is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and Rf 102 , and Rf 103 Rf each independently represents a hydrogen atom, a halogen atom, an alkyl group having from 1 to 5 carbon atoms, or a halogenated alkyl group having from 1 to 5 carbon atoms; 102 , and Rf 103 may be the same or different. 1 is an integer between 0 and 5, and Rf 101 is an organic group containing a fluorine atom.

[0215] R bonded to the carbon atom at the α-position is a hydrogen atom or an alkyl group having from 1 to 5 carbon atoms. R is preferably a hydrogen atom or a methyl group. Rf 102 , and Rf 103 As the halogen atom for Rf, a fluorine atom is preferred. 102 , and Rf 103 As the alkyl group having 1 to 5 carbon atoms as Rf, a methyl group and an ethyl group are preferred. 102 , and Rf 103Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms as Rf include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is preferred. 102 , and Rf 103 As the alkyl group, a hydrogen atom, a fluorine atom, and an alkyl group having 1 to 5 carbon atoms are preferred, and a hydrogen atom, a fluorine atom, a methyl group, and an ethyl group are more preferred. nf 1 is an integer of 0 or more and 5 or less, preferably an integer of 0 or more and 3 or less, and more preferably 1 or 2.

[0216] Rf 101 is an organic group containing a fluorine atom. As the organic group containing a fluorine atom, a hydrocarbon group containing a fluorine atom is preferred. The structure of the fluorine atom-containing hydrocarbon group may be linear, branched, cyclic, or a combination of these structures. The number of carbon atoms in the fluorine atom-containing hydrocarbon group is preferably 1 to 20, more preferably 1 to 15, and even more preferably 1 to 10. Furthermore, in a hydrocarbon group containing a fluorine atom, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more, and particularly preferably 60% or more. Rf 101 is more preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, and further preferably a trifluoromethyl group, -CH2-CF3, -CH2-CF2-CF3, -CH(CF3)2, -CH2-CH2-CF3, and -CH2-CH2-CF2-CF2-CF2-CF3.

[0217] The weight average molecular weight (Mw) of the fluorine additive (F) (based on polystyrene conversion by gel permeation chromatography) is preferably 1,000 or more and 50,000 or less, more preferably 5,000 or more and 40,000 or less, and even more preferably 10,000 or more and 30,000 or less. The dispersity (Mw / Mn) of the fluorine additive (F) is preferably 1.0 or more and 5.0 or less, more preferably 1.0 or more and 3.0 or less, and even more preferably 1.0 or more and 2.5 or less.

[0218] The fluorine additive (F) may be used alone or in combination of two or more kinds. When the photosensitive composition contains a fluorine additive component (F), the content of the fluorine additive (F) is usually 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the silicon-containing polymer (A).

[0219] <Organic solvent (S)> The photosensitive composition may contain an organic solvent (S), and preferably contains an organic solvent (S) for the purpose of adjusting the coating properties. The organic solvent (S) may be any solvent that can dissolve each component used and form a homogeneous solution, and any solvent can be appropriately selected from solvents that have been conventionally known as solvents for chemically amplified photosensitive compositions. Examples of the organic solvent (S) include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, and dipropylene glycol monoacetate; and compounds having an ether bond such as monoalkyl ethers or monophenyl ethers of the polyhydric alcohols or the compounds having an ester bond, such as monomethyl ether, monoethyl ether, monopropyl ether, and monobutyl ether. and derivatives of polyhydric alcohols such as those listed above (among these, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred); cyclic ethers such as dioxane, and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, and mesitylene, and dimethyl sulfoxide (DMSO). The organic solvent (S) may be used alone or in a mixed solvent of two or more kinds. Among the above organic solvents (S), PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

[0220] The organic solvent (S) is preferably a mixed solvent of PGMEA and a polar solvent. The blending ratio (mass ratio) may be appropriately determined taking into consideration the compatibility of PGMEA with the polar solvent, and is preferably within the range of 1:9 to 9:1, more preferably 2:8 to 8:2. More specifically, when EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA:EL or cyclohexanone is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. When PGME is blended as the polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. Furthermore, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferred. As another preferred organic solvent (S), a mixed solvent of at least one selected from PGMEA and EL with γ-butyrolactone is also preferred, in which the mass ratio of the former to the latter is preferably 70:30 to 95:5.

[0221] The amount of the organic solvent (S) used is not particularly limited, and is appropriately set depending on the coating film thickness within a range in which the solid content concentration of the photosensitive composition can be applied to a substrate or the like. The solid content concentration of the photosensitive composition is preferably in the range of 0.1% by mass to 10% by mass, more preferably 0.2% by mass to 5% by mass.

[0222] <Other ingredients> In addition to the components described above, the photosensitive composition may contain other components such as additional resins, dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, and dyes, as appropriate. For example, the photosensitive composition may contain, in addition to the silicon-containing polymer (A), a silicon-free resin such as a hydroxystyrene resin or a novolak resin as an additional resin.

[0223] <Method for producing patterned cured film> The method for producing a patterned cured film includes forming a coating film made of a photosensitive composition on a support (hereinafter also referred to as a "coating film forming step"), position-selectively exposing the coating film (hereinafter also referred to as an "exposure step"), and developing the exposed coating film to form a patterned cured film (hereinafter also referred to as a "development step").

[0224] <Coating film formation process> First, the above-mentioned photosensitive composition is applied onto a support using a spinner or the like to form a coating film. The support is not particularly limited, and conventionally known supports can be used, such as substrates for electronic components and supports on which a predetermined wiring pattern is formed. More specifically, examples include silicon wafers, substrates made of metals such as copper, chromium, iron, and aluminum, and glass substrates. Metals such as copper, aluminum, nickel, and gold can be used as materials for the wiring pattern. The support may be a support having an inorganic and / or organic film provided on the substrate as described above. Examples of inorganic films include inorganic anti-reflective coatings (inorganic BARCs). Examples of organic films include organic anti-reflective coatings (organic BARCs) and organic films such as lower organic films in multilayer resist methods.

[0225] After application of the photosensitive composition, the film made of the photosensitive composition is subjected to a baking (post-apply bake (PAB)) treatment. The conditions for the baking treatment are not particularly limited as long as a patterned cured film having the desired shape and properties can be formed. Preferred baking conditions include, for example, heating at a temperature of 80°C to 150°C for 40 to 120 seconds, preferably 60 to 90 seconds.

[0226] <Exposure process> Next, the coating film is subjected to position-selective exposure using an exposure device such as an electron beam lithography device or an EUV (extreme ultraviolet) exposure device, either through a mask (mask pattern) on which a predetermined pattern is formed, or by direct irradiation with electron beams without using a mask pattern.

[0227] The wavelength of the light used for exposure is not particularly limited, and radiation such as ArF excimer laser, KrF excimer laser, F2 excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, and soft X-ray can be used. In the method for producing the patterned cured film, the method is particularly useful for exposing the coated film to EUV (extreme ultraviolet) or EB (electron beam). Furthermore, among EUV, it is also preferable to use radiation of so-called BEUV, which has a wavelength of 13.5 nm or less, for example, in the range of 3 to 11 nm, 5 to 11 nm, 5 to 8 nm, or 6.5 to 6.8 nm, and particularly a wavelength of 6.7 nm. This is because, compared to the 13.5 nm radiation commonly used in EUV lithography, the shorter wavelength can provide better resolution (features below the 13.5 nm node), a large depth of focus (DOF), and high throughput. When the photosensitive resin composition of the present invention is exposed to BEUV radiation, it is preferable to use a compound containing at least one element selected from the group consisting of Ta, W, Re, Os, Ir, Ni, Cu, Sn, S, Ga, Ge, Gd, Hf, Tm, Zn, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Yb, Lu, Pt, and Au.

[0228] The exposure method for the coating film may be a normal exposure (dry exposure) carried out in air or an inert gas such as nitrogen, or may be liquid immersion lithography. After the exposure, the exposed coating film is optionally baked (post-exposure bake (PEB)). Preferred baking conditions include, for example, heating at a temperature of 80° C. to 150° C. for 40 to 120 seconds, preferably 60 to 90 seconds.

[0229] <Developing process> The regioselectively exposed coating film is then developed to obtain a patterned hardened film, typically by an alkaline development process or a solvent development process.

[0230] When development is carried out by an alkaline development process, an alkaline developer is used, such as an aqueous solution of tetramethylammonium hydroxide (TMAH) with a concentration of 0.1% by mass to 10% by mass.

[0231] When development is carried out by a solvent development process, a developer containing an organic solvent (organic developer) is used. The organic solvent contained in the organic developer used in the development treatment in the solvent development process may be any organic solvent that can dissolve component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specific examples include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, as well as hydrocarbon solvents and halogenated hydrocarbon solvents. Ketone-based solvents are organic solvents that contain CC(=O)-C in their structure. Ester-based solvents are organic solvents that contain CC(=O)-OC in their structure. Alcohol-based solvents are organic solvents that contain an alcoholic hydroxyl group in their structure. "Alcoholic hydroxyl group" means a hydroxyl group bonded to a carbon atom of an aliphatic hydrocarbon group. Nitrile-based solvents are organic solvents that contain a nitrile group in their structure. Amide-based solvents are organic solvents that contain a carboxylic acid amide group in their structure. Ether-based solvents are organic solvents that contain COC in their structure. Some organic solvents contain multiple types of functional groups that characterize the above-mentioned solvents in their structure, and in such cases, the term "organic solvent" refers to any solvent type containing the functional groups possessed by the organic solvent. For example, diethylene glycol monomethyl ether corresponds to both the alcohol-based solvent and the ether-based solvent in the above classification. A hydrocarbon solvent is a solvent made of hydrocarbon. A halogenated hydrocarbon solvent is a solvent made of hydrocarbon having only halogen atoms as substituents. The halogen atoms are preferably fluorine atoms. The organic solvent contained in the organic developer is preferably a polar solvent, and preferred are ketone-based solvents, ester-based solvents, and alcohol-based solvents.

[0232] Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methyl naphthyl ketone, isophorone, and methyl amyl ketone (2-heptanone). Among these, methyl amyl ketone (2-heptanone) is preferred.

[0233] Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, and 2-ethoxybutyl acetate. acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, ethyl carbonate, Examples of the ester solvent include propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl 3-methoxypropionate, and γ-butyrolactone. Among these, butyl acetate is preferred as the ester solvent.

[0234] Examples of alcohol-based solvents include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, 4-methyl-2-pentanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol, and diethylene glycol monomethyl ether.

[0235] The organic developer may contain known additives as needed. Examples of such additives include surfactants. The surfactants are not particularly limited, but may include, for example, ionic or nonionic fluorine-based and / or silicon-based surfactants.

[0236] Development can be carried out by a known developing method. Suitable examples of the developing method include a method of immersing a support in a developer for a certain period of time (dip method), a method of piling up a developer on the surface of a support by surface tension and leaving it standing for a certain period of time (puddle method), a method of spraying a developer on the surface of a support (spray method), and a method of continuously dispensing a developer while scanning a developer dispensing nozzle at a constant speed onto a support rotating at a constant speed (dynamic dispense method).

[0237] After development, the patterned cured film is preferably subjected to a rinse treatment. In the case of an alkaline development process, rinsing with pure water is preferred. In the case of a solvent development process, rinsing with a rinse solution containing an organic solvent is preferred. The rinsing treatment can be carried out by a known rinsing method, such as a method of continuously applying a rinsing liquid onto a support rotating at a constant speed (spin coating method), a method of immersing a support in a rinsing liquid for a certain period of time (dipping method), or a method of spraying a rinsing liquid onto the surface of the support (spray method). In the case of a solvent development process, after development or after development and rinsing treatment, a treatment may be carried out in which the developer or rinsing liquid adhering to the patterned cured film is removed with a supercritical fluid. Usually, after development or rinsing, the patterned cured film is dried. If necessary, after the development, the patterned cured film may be subjected to a baking treatment (post-baking).

[0238] As described above, the present inventors provide the following (1) to (11). (1) A silicon-containing polymer (A) having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group, and a photoacid generator (B), The photosensitive composition, wherein the photoacid generator (B) comprises a photoacid generator (B1) having a sulfonium cation containing an iodine atom. (2) The photosensitive composition according to (1), wherein the sulfonium cation is a sulfonium cation represented by the following formula (b1-1): [ka] (In formula (b1-1), R b11 is an iodine atom, or -R b111 -X b1 and R b111 is a divalent linking group that does not contain an aromatic group, and X b1 is an aromatic group substituted with an iodine atom, and R b12 is a fluorine atom, a hydroxyl group, a hydrocarbon group which may have a substituent, or an alkoxy group which may have a substituent, and R b13 , and R b14 are each independently a hydrocarbon group which may have a substituent, and R b13 , and R b14 may be bonded to each other to form a ring, q1 is an integer of 1 or more and 4 or less, q2 is an integer of 0 or more and 3 or less, and 1≦q1+q2≦4. (3) The above R b111 The photosensitive composition according to (2), wherein the divalent linking group not containing an aromatic group as represented by the formula (b1-1a) is a divalent aliphatic hydrocarbon group or a group represented by the following formula (b1-1a): -L b1 -R b112 -L b2 -* (b1-1a) (In formula (b1-1a), L b1 is an ester bond, an amide bond, or an ether bond, and L b2 is a single bond, an ester bond, an amide bond, or an ether bond, and R b112 is a single bond or an alkylene group, and * is X b1 ) (4) The photosensitive composition according to any one of (1) to (3), wherein the silicon-containing polymer (A) comprises a structural unit represented by the following formula (a1) and a structural unit represented by the following formula (a2): [ka] (In formula (a1), R a11 is an organic group having a phenolic hydroxyl group, and * is a bond. [ka] (In formula (a2), R a21 is an organic group having an alkali-soluble group protected by an acid-labile group, and * is a bond. (5) The above R a21 is a group represented by the following formula (a2-1) or a group represented by the following formula (a2-2): [ka] (In formula (a2-1), L a1 is a single bond or a divalent organic group, and R a22 is a hydrogen atom or a hydrocarbon group which may have a substituent, and R a23 is a hydrogen atom or a hydrocarbon group which may have a substituent, and R a22 , and R a23 may be bonded to each other to form a ring, and * represents a bond.) [ka] (In formula (a2-2), L a2 is a single bond or a divalent organic group, and X a2 is a single bond or O, and R a24 , R a25 , and R a26 are each independently a hydrocarbon group, and R a24 , R a25 , and R a26 Two or more of may be bonded to each other to form a ring, and * represents a bond.) (6) The photosensitive composition according to any one of (1) to (5), further comprising a base component (D) that controls the diffusion of an acid generated by exposure. (7) The photosensitive composition according to any one of (1) to (6), wherein the ratio of the mass of the silicon-containing polymer (A) to the mass of the solid content of the photosensitive composition is 10 mass % or more. (8) The photosensitive composition according to any one of (1) to (7), further comprising a crosslinking agent (C). (9) The photosensitive resin composition according to any one of (1) to (8), which is a positive photosensitive resin composition. (10) Forming a coating film made of the photosensitive composition according to any one of (1) to (9) on a support; exposing the coating film to position-selective light; and developing the exposed coating film to form a patterned cured film. A method for producing a patterned cured film. (11) The method for producing a patterned cured film according to (10), wherein the coating film is exposed to EUV (extreme ultraviolet) rays. [Example]

[0239] The present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[0240] <Preparation of Photosensitive Composition> The components shown in Table 1 were mixed and dissolved to prepare the photosensitive compositions of the respective examples.

[0241] [Table 1]

[0242] In Table 1, the abbreviations have the following meanings: The values ​​in brackets [ ] are the amounts (parts by mass) of each component.

[0243] (A)-1: A polymer represented by the following formula (weight average molecular weight (Mw) measured by GPC in terms of standard polystyrene: 3,900, molecular weight dispersity (Mw / Mn): 1.3, silicon atom content: 20.0% by mass). [ka]

[0244] (A)-2: Polymer represented by the following formula (weight average molecular weight (Mw) measured by GPC in terms of standard polystyrene: 2,500, molecular weight dispersity (Mw / Mn): 1.3, silicon atom content: 14.9% by mass). [ka]

[0245] (A)-3: Polymer represented by the following formula (weight average molecular weight (Mw) measured by GPC in terms of standard polystyrene: 4,800, molecular weight dispersity (Mw / Mn): 1.4, silicon atom content: 19.4% by mass). [ka]

[0246] (A)-4: Polymer represented by the following formula (weight average molecular weight (Mw) measured by GPC in terms of standard polystyrene: 4,000, molecular weight dispersity (Mw / Mn): 1.3, silicon atom content: 20.5% by mass). [ka]

[0247] (A)-5: Polymer represented by the following formula (weight average molecular weight (Mw) measured by GPC in terms of standard polystyrene: 2300, molecular weight dispersity (Mw / Mn): 1.1, silicon atom content: 13% by mass). [ka]

[0248] (A)-6: Polymer represented by the following formula (weight average molecular weight (Mw) measured by GPC in terms of standard polystyrene: 4,100, molecular weight dispersity (Mw / Mn): 1.4, silicon atom content: 0% by mass). [ka]

[0249] (B)-1: A compound represented by the following formula: [ka]

[0250] (B)-2: A compound represented by the following formula: [ka]

[0251] (B)-3: A compound represented by the following formula: [ka]

[0252] (B)-4: A compound represented by the following formula: [ka]

[0253] (B)-5: A compound represented by the following formula: [ka]

[0254] (C)-1: A compound represented by the following formula: [ka]

[0255] (C)-2: A compound represented by the following formula: [ka]

[0256] (D)-1: A compound represented by the following formula: [ka]

[0257] (D)-2: A compound represented by the following formula: [ka]

[0258] (E)-1: A compound represented by the following formula: [ka]

[0259] (S)-1: Propylene glycol monomethyl ether (S)-2: Propylene glycol monomethyl ether acetate (S)-3: Cyclohexanone

[0260] <Synthesis of Compounds (B)-1 to (B)-4, and Compound (D)-2> (Synthesis of sulfonium salt (Y-1)) 70.2 g of sulfonium salt (X-1) (CAS. 3028611-48-2), 53.7 g of benzyldimethylstearylammonium chloride, 351 g of 4-methyltetrahydropyran, and 842 g of pure water were mixed, and the mixture was stirred at room temperature for 30 minutes, after which the aqueous layer was recovered using a separatory funnel. Then, 351 g of pure water was added to the remaining organic layer, and the mixture was stirred for 30 minutes, and the aqueous layer was recovered using a separatory funnel. This process was repeated three times. All of the recovered aqueous layers were mixed. 632 g of 4-methyltetrahydropyran was added to the aqueous layer, and the mixture was stirred for 30 minutes, and the aqueous layer was recovered using a separatory funnel. This process was repeated four times to obtain a 2.8% aqueous solution of sulfonium salt (Y-1). [ka]

[0261] (Synthesis of sulfonium salt (Y-2)) 93.2 g of sulfonium salt (X-2) (CAS. 3028611-54-0), 53.7 g of benzyldimethylstearylammonium chloride, 351 g of 4-methyltetrahydropyran, and 842 g of pure water were mixed, and the mixture was stirred at room temperature for 30 minutes, after which the aqueous layer was collected using a separatory funnel. Then, 351 g of pure water was added to the remaining organic layer, and the mixture was stirred for 30 minutes, and the aqueous layer was collected using a separatory funnel. This process was repeated three times. All of the collected aqueous layers were mixed. 632 g of 4-methyltetrahydropyran was added to the aqueous layer, and the mixture was stirred for 30 minutes, and the aqueous layer was collected using a separatory funnel. This process was repeated four times to obtain a 3.0% aqueous solution of sulfonium salt (Y-2). [ka]

[0262] (Synthesis of sulfonium salt (Y-3)) 72.0 g of sulfonium salt (X-3) (CAS. 3028611-58-4), 53.7 g of benzyldimethylstearylammonium chloride, 351 g of 4-methyltetrahydropyran, and 842 g of pure water were mixed, and the mixture was stirred at room temperature for 30 minutes, after which the aqueous layer was collected using a separatory funnel. Then, 351 g of pure water was added to the remaining organic layer, and the mixture was stirred for 30 minutes, and the aqueous layer was collected using a separatory funnel. This process was repeated three times. All of the collected aqueous layers were mixed. 632 g of 4-methyltetrahydropyran was added to the aqueous layer, and the mixture was stirred for 30 minutes, and the aqueous layer was collected using a separatory funnel. This process was repeated four times to obtain a 2.9% aqueous solution of sulfonium salt (Y-3). [ka]

[0263] (Synthesis of Compound (B)-1) 195 g of a 2.8% aqueous solution of sulfonium salt (Y-1), 7.9 g of benzyltrimethylammonium salt (Z-1) (CAS. 2920109-86-8), and 195 g of dichloromethane were mixed. The mixture was stirred at room temperature for 30 minutes, and then the organic layer was collected using a separatory funnel. Next, 195 g of a 0.3% aqueous solution of sulfonium salt (Y-1) was added to the organic layer, and the mixture was stirred at room temperature for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated three times. Furthermore, 195 g of pure water was added to the organic layer, and the mixture was stirred for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated three times to remove impurities. The solvent was then removed using a rotary evaporator, and the mixture was further vacuum-dried using a hydraulic vacuum pump for 20 hours, yielding 9.9 g of compound (B)-1. [ka]

[0264] The structure of compound (B)-1 is: 13 C-NMR, and 19 This was confirmed by F-NMR. [ 13 C-NMR (150 MHz, acetone-d)] a:1C, 90ppm b, c: 2C, 162 ppm d:1C,63ppm e:1C, 118-122 ppm f:1C,105ppm [ 19 F-NMR (150 MHz, DMSO-d)] h:2F,-113ppm i:4F,-104ppm [ka]

[0265] (Synthesis of Compound (B)-2) 255 g of a 3.0% aqueous solution of sulfonium salt (Y-2), 7.9 g of benzyltrimethylammonium salt (Z-1) (CAS. 2920109-86-8), and 255 g of dichloromethane were mixed, and the mixture was stirred at room temperature for 30 minutes, after which the organic layer was collected using a separatory funnel. Next, 255 g of a 0.3% aqueous solution of sulfonium salt (Y-2) was added to the organic layer, and the mixture was stirred at room temperature for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated three times. Furthermore, 255 g of pure water was added to the organic layer, and the mixture was stirred for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated three times to remove impurities. The solvent was then removed using a rotary evaporator, and the mixture was further vacuum-dried using a hydraulic vacuum pump for 20 hours, yielding 10.9 g of compound (B)-2. [ka]

[0266] The structure of compound (B)-2 is: 13 C-NMR, and 19 This was confirmed by F-NMR. [ 13 C-NMR (150 MHz, acetone-d)] a:1C, 90ppm b, c: 2C, 162 ppm d:1C,63ppm e:1C, 118-122 ppm f:1C,112ppm [ 19 F-NMR (150 MHz, DMSO-d)] g:2F,-113ppm h:12F,-57ppm [ka]

[0267] (Synthesis of Compound (B)-3) 294 g of a 2.9% aqueous solution of sulfonium salt (Y-3), 7.9 g of benzyltrimethylammonium salt (Z-1) (CAS. 2920109-86-8), and 194 g of dichloromethane were mixed, and the mixture was stirred at room temperature for 30 minutes, after which the organic layer was collected using a separatory funnel. Next, 194 g of a 0.3% aqueous solution of sulfonium salt (Y-3) was added to the organic layer, and the mixture was stirred at room temperature for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated three times. Furthermore, 194 g of pure water was added to the organic layer, and the mixture was stirred for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated three times to remove impurities. The solvent was then removed using a rotary evaporator, and the mixture was further vacuum-dried using a hydraulic vacuum pump for 20 hours, yielding 9.7 g of compound (B)-3. [ka]

[0268] The structure of compound (B)-3 is: 13 C-NMR, and 19 This was confirmed by F-NMR. [ 13 C-NMR (150 MHz, acetone-d)] a:1C, 90ppm b, c: 2C, 162 ppm d:1C,63ppm e:1C, 118-122 ppm f:1C,106ppm g:1C,168ppm [ 19F-NMR (150 MHz, DMSO-d)] h:2F,-113ppm i:4F,-104ppm [ka]

[0269] (Synthesis of Compound (B)-4) 195 g of a 2.8% aqueous solution of sulfonium salt (Y-1), 11.2 g of benzyltrimethylammonium salt (Z-2) obtained by the method described in JP 2023-123183 A, and 194 g of dichloromethane were mixed, and the mixture was stirred at room temperature for 30 minutes, and then the organic layer was collected using a separatory funnel. Next, 194 g of a 0.3% aqueous solution of sulfonium salt (Y-1) was added to the organic layer, and the mixture was stirred at room temperature for 30 minutes, and then the organic layer was collected using a separatory funnel. This process was repeated three times. Furthermore, 194 g of pure water was added to the organic layer, and the mixture was stirred for 30 minutes, and then the organic layer was collected using a separatory funnel. This process was repeated three times to remove impurities. Then, the solvent was distilled off using a rotary evaporator, and the mixture was further vacuum-dried for 20 hours using a hydraulic vacuum pump, yielding 13.2 g of compound (B)-4. [ka]

[0270] The structure of compound (B)-4 is: 13 C-NMR, and 19 This was confirmed by F-NMR. [ 13 C-NMR (150 MHz, acetone-d)] a:1C, 90ppm b, c: 2C, 162 ppm d:1C,63ppm e:1C, 118-122 ppm f:1C,105ppm [ 19 F-NMR (150 MHz, DMSO-d)] h:2F,-113ppm i:4F,-104ppm [ka]

[0271] (Synthesis of Compound (D)-2) 195 g of a 2.8% aqueous solution of sulfonium salt (Y-1), 2.1 g of tetramethylammonium salicylate (CAS. 68494-18-8), and 194 g of dichloromethane were mixed, and the mixture was stirred at room temperature for 30 minutes, after which the organic layer was collected using a separatory funnel. Next, 194 g of pure water was added to the organic layer, and the mixture was stirred for 30 minutes. The organic layer was then collected using a separatory funnel. This process was repeated five times to remove impurities. The solvent was then removed using a rotary evaporator, and the mixture was further vacuum dried using a hydraulic vacuum pump for 20 hours, yielding 3.9 g of compound (D)-2. [ka]

[0272] The structure of compound (D)-2 is: 13 C-NMR, and 19 This was confirmed by F-NMR. [ 13 C-NMR (150 MHz, acetone-d)] a:1C, 172 ppm b: 1C, 164 ppm f:1C,105ppm [ 19 F-NMR (150 MHz, DMSO-d)] h:2F,-113ppm i:4F,-104ppm [ka]

[0273] <Ratio of silicon atoms to the solid content of the photosensitive composition> The content of silicon atoms in the solid content of the photosensitive composition was calculated as follows. In the case of the photosensitive composition of Example 1, the content of silicon atoms in the compound (A)-1 was 20.0% by mass. The content of the compound (A)-1 in the solid content of the photosensitive composition is (100 / (100+30+32+3))×100≒60.6 (mass%). Therefore, the content of silicon atoms in the solid content of the photosensitive composition is The calculation is 20.0 × (60.6 / 100) ≒ 12 (mass%).

[0274] <Formation of patterned cured film> A resist organic underlayer film composition "AL412" (manufactured by Brewer Science) was applied to a 12-inch silicon wafer using a spin coater, and the applied film was baked on a hot plate at 205°C for 60 seconds to form an organic underlayer film with a thickness of 22 nm. The photosensitive composition of each example was applied onto the organic underlayer film using a spin coater, and the coating film was pre-baked (PAB) on a hot plate at 90°C for 60 seconds to form a coating film with a thickness of 30 nm.

[0275] Next, the coating film was irradiated with EUV light (13.5 nm) through a photomask using an EUV exposure system NXE3400 (manufactured by ASML, NA (numerical aperture) = 0.33, illumination conditions: Annular σ-in = 0.595, σ-out = 0.817). Thereafter, post-exposure baking (PEB) was performed at 80° C. for 60 seconds.

[0276] Next, in Examples 1 to 12 and Comparative Examples 1 to 3, development was performed for 30 seconds with a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) (trade name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23°C. After that, a 30-second rinse with pure water was performed, and the resist was shaken off and dried. In Examples 13 to 15, development was performed for 13 seconds with butyl acetate at 23°C. As a result, a line and space pattern (LS pattern) with a line width of 14 nm was formed.

[0277] [Evaluation of optimal exposure (Eop)] The optimal exposure dose Eop (mJ / cm) for forming an LS pattern with a line width of 14 nm by forming the above patterned cured film. 2 The results are shown in Table 2.

[0278] [Evaluation of LWR (Line Width Roughness)] The LS pattern having a line width of 14 nm formed by forming the patterned cured film described above was subjected to 3σ measurement, which is a measure of LWR. "3σ" refers to three times the standard deviation (σ) (unit: nm) (3σ) obtained from the measurement results of 400 line positions measured in the longitudinal direction of the line using a scanning electron microscope (accelerating voltage 800 V, product name: S-9380, manufactured by Hitachi High-Technologies Corporation). The results are shown in Table 2. The smaller the 3σ value, the less roughness there was on the line sidewall, meaning that an LS pattern with a more uniform width was obtained.

[0279] [Evaluation of dry etching resistance] The photosensitive composition of each example was applied onto an 8-inch silicon wafer using a spin coater, and the applied film was baked on a hot plate at 90°C for 60 seconds to form a coated film with a thickness of 50 nm. An 8% by mass propylene glycol monomethyl ether acetate solution of cresol novolac resin (a resin represented by the formula below, weight average molecular weight (Mw) in terms of standard polystyrene as measured by GPC: 33,000, molecular weight dispersity (Mw / Mn): 16.8) synthesized by a standard method was applied onto an 8-inch silicon wafer using a spin coater, and the applied film was baked on a hot plate at 280°C for 60 seconds to form an organic film for comparison of etching resistance with a thickness of 200 nm. [ka]

[0280] The cured films and the organic films for etching resistance comparison were each treated for 30 seconds in a TCP-type dry etching apparatus (O flow rate = 5 sccm, Ar flow rate = 15 sccm, pressure = 0.05 Pa, temperature = 0°C, plasma source RF power = 200 W, bias RF power = 100 W). The etching rate ratio of each cured film formed from each photosensitive composition to the etching-resistant organic film for comparison was calculated. The results are shown in Table 2. If this etching rate ratio is 0.5 or less, it can be said that the etching resistance is good.

[0281] [Table 2]

[0282] It can be seen from Table 2 that the photosensitive compositions of Examples 1 to 11 are capable of forming finely sized patterns that have both etching resistance and lithography properties.

Claims

1. The composition contains a silicon-containing polymer (A) having a phenolic hydroxyl group and an alkali-soluble group protected by an acid-dissociable group, and a photoacid generator (B), The photosensitive composition, wherein the photoacid generator (B) comprises a photoacid generator (B1) having a sulfonium cation containing an iodine atom.

2. 2. The photosensitive composition according to claim 1, wherein the sulfonium cation is a sulfonium cation represented by the following formula (b1-1): 【Chemistry 1】 (In formula (b1-1), R ｂ１１ is an iodine atom, or -R ｂ１１１ -X ｂ１ and R ｂ１１１ is a divalent linking group containing no aromatic group, and X ｂ１ is an aromatic group substituted with an iodine atom, and R ｂ１２ represents a fluorine atom, a hydroxyl group, a hydrocarbon group which may have a substituent, or an alkoxy group which may have a substituent, and R ｂ１３ , and R ｂ１４ are each independently a hydrocarbon group which may have a substituent, and R ｂ１３ , and R ｂ１４ may be bonded to each other to form a ring, q1 is an integer of 1 or more and 4 or less, q2 is an integer of 0 or more and 3 or less, and 1≦q1+q2≦4.

3. The R ｂ１１１ The photosensitive composition according to claim 2, wherein the divalent linking group containing no aromatic group as represented by the formula (b1-1a) is a divalent aliphatic hydrocarbon group or a group represented by the following formula (b1-1a): -L ｂ１ -R ｂ１１２ -L ｂ２ -* (b1-1a) (In formula (b1-1a), L ｂ１ is an ester bond, an amide bond, or an ether bond, and L ｂ２ is a single bond, an ester bond, an amide bond, or an ether bond, and R ｂ１１２ is a single bond or an alkylene group, * is X ｂ１ It is a bond with

4. 2. The photosensitive composition according to claim 1, wherein the silicon-containing polymer (A) comprises a structural unit represented by the following formula (a1) and a structural unit represented by the following formula (a2): 【Chemistry 2】 (In formula (a1), R ａ１１ is an organic group having a phenolic hydroxyl group, and * is a bond. 【Transformation 3】 (In formula (a2), R ａ２１ represents an organic group having an alkali-soluble group protected by an acid-labile group, and * represents a bond.

5. The R ａ２１ is a group represented by the following formula (a2-1) or a group represented by the following formula (a2-2): 【Chemistry 4】 (In formula (a2-1), L ａ１ is a single bond or a divalent organic group, and R ａ２２ is a hydrogen atom or a hydrocarbon group which may have a substituent, and R ａ２３ is a hydrogen atom or a hydrocarbon group which may have a substituent, and R ａ２２ , and R ａ２３ may be bonded to each other to form a ring, and * represents a bond. 【Transformation 5】 (In formula (a2-2), L ａ２ is a single bond or a divalent organic group, and X ａ２ is a single bond or O, and R ａ２４ , R ａ２５ , and R ａ２６ are each independently a hydrocarbon group, and R ａ２４ , R ａ２５ , and R ａ２６ Two or more of may be bonded to each other to form a ring, and * represents a bond.

6. 2. The photosensitive composition according to claim 1, further comprising a base component (D) that controls the diffusion of an acid generated by exposure.

7. 2. The photosensitive composition according to claim 1, wherein the ratio of the mass of the silicon-containing polymer (A) to the mass of the solid content of the photosensitive composition is 10 mass % or more.

8. The photosensitive composition according to claim 1 , further comprising a crosslinking agent (C).

9. 10. The photosensitive composition of claim 1, wherein the photosensitive composition is positive-acting.

10. forming a coating film made of the photosensitive composition according to any one of claims 1 to 9 on a support; exposing the coating film to position-selective light; and developing the exposed coating film to form a patterned cured film. A method for producing a patterned cured film.

11. The method for producing a patterned cured film according to claim 10, wherein the coating film is exposed to EUV (extreme ultraviolet) rays.

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