Photoresist pattern forming method

Abstract

A method for forming a photoresist pattern includes: (i) a step of forming a photoresist film on a support using a photoresist composition; (ii) a step of exposing the photoresist film; and (iii) a step of developing the exposed photoresist film to form a photoresist pattern, characterized in that the photoresist composition contains: a resin (A) whose solubility in the developer changes due to the action of an acid, an acid-generating agent (B) that generates acid upon exposure, a photodegradable alkali (D1), a solvent (S), and a compound (X) represented by the following formula (x-1), wherein the amount of solvent remaining in the photoresist film formed in step (i) is 910 ppm or more, wherein R 1 ~R 4 It is a hydroxyl group or an alkyl group having 1 to 5 carbon atoms, R 5 and R 6 It is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 10 carbon atoms obtained by substitution with a hydroxyl group.

Description

TECHNICAL FIELD

[0001] The present application relates to a photoresist pattern forming method. BACKGROUND

[0002] In a photolithography technique, a process such as forming a photoresist film composed of a resist material on a substrate, selectively exposing the photoresist film, and performing a development treatment to form a photoresist pattern of a prescribed shape on the photoresist film is performed. A resist material in which the exposed portion of the photoresist film changes to a property of dissolving in a developer is called a positive type, and a resist material in which the exposed portion of the photoresist film changes to a property of not dissolving in a developer is called a negative type.

[0003] In recent years, in the production of semiconductor elements and liquid crystal display elements, due to the progress of photolithography techniques, the miniaturization of patterns has been developed. As a method of miniaturization, generally, the shortening of the wavelength (the increase of the energy) of the exposure light source is performed. Specifically, in the past, ultraviolet rays typified by g-rays and i-rays were used, and now, KrF excimer laser or ArF excimer laser is used for mass production of semiconductor elements. In addition, researches on EUV (extreme ultraviolet rays), EB (electron beams), X-rays, and the like, which have shorter (higher energy) wavelengths than these excimer lasers, are also being conducted.

[0004] In the progress of further progress of photolithography techniques, the expansion of application fields, and the like, in the formation of photoresist patterns, improvement of various lithography properties such as high sensitivity, resolution, and roughness is required.

[0005] As a photoresist composition for forming a photoresist film, generally, a photoresist composition containing a resin component whose solubility to a developer changes due to the action of an acid, and an acid generator component that generates an acid by exposure is used. The photoresist composition can contain a nitrogen-containing compound as an acid diffusion control agent component that traps an acid generated by exposure. As compared with the conventional amine type acid diffusion control agent, if a photodegradable base form acid diffusion control agent that loses the acid diffusion controllability by decomposition by exposure is used, the resolution can be improved, but in the case where a photodegradable base is used as an acid diffusion control agent in a KrF negative type photoresist, there is a problem that it is difficult to maintain the shape in a state where the high resolution is maintained.

[0006] On the other hand, it is pointed out that due to the thinning along with the miniaturization of the resist, problems such as an increase in line edge roughness of the film and a reduction in the pattern film occur, and it is known that in order to reduce the line edge roughness, it is necessary to make the amount of the solvent remaining in the film appropriate (see Patent Document 1). However, the effective method of controlling the amount of the solvent remaining in the film or the relationship between the amount of the solvent remaining in the film and other properties of the resist has not been sufficiently understood.

[0007] Prior Art Documents

[0008] Patent Documents

[0009] Patent Document 1: Japanese Patent No. 4857208 SUMMARY

[0010] PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] The present invention has been achieved in view of the above circumstances, and provides a photoresist pattern forming method capable of forming a pattern of good shape while maintaining a high resolution.

[0012] SOLUTION TO THE PROBLEM

[0013] To achieve the above object, the present invention employs the following configuration. The present inventors have found that the above problem can be solved by a photoresist pattern forming method as described below, and thus have completed the present invention.

[0014] A photoresist pattern forming method comprising:

[0015] (i) a step of forming a photoresist film on a support using a photoresist composition;

[0016] (ii) a step of exposing the photoresist film; and

[0017] (iii) a step of developing the exposed photoresist film to form a photoresist pattern, the photoresist pattern forming method being characterized in that,

[0018] the photoresist composition contains a resin (A) whose solubility in a developer changes due to the action of an acid, an acid generator (B) that generates an acid by exposure, a photodegradable base (D1), a solvent (S), and a compound (X) represented by the following formula (x-1),

[0019] [Chemical Formula 1]

[0020]

[0021] [In the formula, R 1 ~R 4 are each independently a hydroxyl group or an alkyl group having a carbon number of 1 to 5, R 5 and R 6 are each independently hydrogen, an alkyl group having a carbon number of 1 to 5, or an alkyl group having a carbon number of 1 to 10 obtained by substituting a hydroxyl group, a, b, c, and d are each independently an integer of 0 to 3, and e and f are each independently an integer of 1 to 2.]

[0022] The amount of the solvent remaining in the photoresist film formed in the process (i) is 910 ppm or more.

[0023] Effects of Invention

[0024] The photoresist pattern obtained by the photoresist pattern forming method of the present application can form a pattern with a good shape while maintaining high resolution. DETAILED DESCRIPTION

[0025] In the description of the present application and the scope of the present claims, "aliphatic" is a relative concept with respect to aromatic, and is defined to mean a group, compound, etc. that does not have aromaticity.

[0026] Unless otherwise specified, "alkyl" includes a 1-valent saturated hydrocarbon group of a linear, branched, and cyclic shape. The same applies to the alkyl group in an alkoxy group.

[0027] Unless otherwise specified, "alkylene" includes a 2-valent saturated hydrocarbon group of a linear, branched, and cyclic shape.

[0028] "Alkyl halide" is a group in which some or all of the hydrogen atoms of an alkyl group are substituted with halogen atoms, and as the halogen atoms, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom can be exemplified.

[0029] "Fluoroalkyl" or "fluoroalkylene" means a group in which some or all of the hydrogen atoms of an alkyl group or an alkylene group are substituted with fluorine atoms.

[0030] "Structural unit" means a monomeric unit (monomer unit) constituting a high molecular compound (resin, polymer, copolymer).

[0031] "Structural unit derived from an acrylate" means a structural unit constituted by cleavage of the ethylenic double bond of an acrylate.

[0032] "Acrylate" is a compound in which the hydrogen atom at the carboxyl terminal of acrylic acid (CH2=CH-COOH) is substituted with an organic group.

[0033] The hydrogen atom bonded to the carbon atom at the α-position of the acrylate can be substituted with a substituent. The substituent (R α0 ) that substitutes the hydrogen atom bonded to the carbon atom at the α-position is an atom or a group other than a hydrogen atom, and can be exemplified by an alkyl group having a carbon number of 1 to 5, a haloalkyl group having a carbon number of 1 to 5, and the like. In addition, unless otherwise specified, the carbon atom at the α-position of the acrylate means the carbon atom to which the carbonyl group of the acrylic acid is bonded.

[0034] Hereinafter, an acrylic ester in which a hydrogen atom bonded to a carbon atom at the α-position is sometimes replaced with a substituent will be referred to as an α-substituted acrylic ester. In addition, an acrylic ester and an α-substituted acrylic ester are sometimes collectively referred to as "(α-substituted) acrylic ester".

[0035] The "structural unit derived from a hydroxystyrene or a hydroxystyrene derivative" means a structural unit formed by cleavage of the olefinic double bond of a hydroxystyrene or a hydroxystyrene derivative.

[0036] The "hydroxystyrene derivative" means a concept including a compound in which a hydrogen atom at the α-position of a hydroxystyrene is replaced with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As the derivatives thereof, there can be mentioned, for example, a compound in which a hydrogen atom of the hydroxyl group of the hydroxystyrene, of which the hydrogen atom at the α-position can be replaced with a substituent, is replaced with an organic group; a compound in which a substituent other than a hydroxyl group is bonded to the benzene ring of the hydroxystyrene, of which the hydrogen atom at the α-position can be replaced with a substituent; and the like. In addition, unless otherwise specified, the α-position (carbon atom at the α-position) of the hydroxystyrene means the carbon atom to which the benzene ring is bonded.

[0037] As the substituent replacing the hydrogen atom at the α-position of the substituted hydroxystyrene, there can be mentioned the same groups as those exemplified above as the substituent at the α-position of the α-substituted acrylic ester.

[0038] The "structural unit derived from a vinylbenzoic acid or a vinylbenzoic acid derivative" means a structural unit formed by cleavage of the olefinic double bond of a vinylbenzoic acid or a vinylbenzoic acid derivative.

[0039] The "vinylbenzoic acid derivative" means a concept including a compound in which a hydrogen atom at the α-position of a vinylbenzoic acid is replaced with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As the derivatives thereof, there can be mentioned, for example, a compound in which a hydrogen atom of the carboxyl group of the vinylbenzoic acid, of which the hydrogen atom at the α-position can be replaced with a substituent, is replaced with an organic group; a compound in which a substituent other than a hydroxyl group and a carboxyl group is bonded to the benzene ring of the vinylbenzoic acid, of which the hydrogen atom at the α-position can be replaced with a substituent; and the like. In addition, unless otherwise specified, the α-position (carbon atom at the α-position) of the vinylbenzoic acid means the carbon atom to which the benzene ring is bonded.

[0040] The "styrene derivative" means a compound in which a hydrogen atom at the α-position of a styrene is replaced with another substituent such as an alkyl group or a halogenated alkyl group, and a compound in which a hydrogen atom of the phenyl group of the styrene is replaced with a lower alkyl group having a carbon number of 1 to 5 or the like as a substituent.

[0041] The "structural unit derived from a styrene" and "structural unit derived from a styrene derivative" mean a structural unit formed by cleavage of the olefinic double bond of a styrene or a styrene derivative.

[0042] The alkyl group used as the substituent at the α-position is preferably a straight-chain or branched alkyl group. Specifically, examples include alkyl groups with 1 to 5 carbon atoms (methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, etc.).

[0043] Furthermore, the alkyl halogroup serving as the α-position substituent can specifically be exemplified by groups obtained by replacing some or all of the hydrogen atoms of the alkyl halogroup serving as the α-position substituent with halogen atoms. Examples of such halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being particularly preferred.

[0044] Furthermore, the hydroxyalkyl group serving as the α-position substituent can specifically be exemplified by groups obtained by replacing some or all of the hydrogen atoms of the alkyl group serving as the α-position substituent with hydroxyl groups. The number of hydroxyl groups in this hydroxyalkyl group is preferably 1 to 5, and most preferably 1.

[0045] When it is stated that "substituents may be present", it includes two cases: replacing the hydrogen atom (-H) with a monovalent group and replacing the methylene group (-CH2-) with a divalent group.

[0046] "Exposure" refers to the concept of exposure to all forms of radiation.

[0047] Method for forming patterns with photoresist

[0048] The photoresist patterning method of the present invention includes:

[0049] (i) The process of forming a photoresist film on a support using a photoresist composition;

[0050] (ii) the process of exposing the photoresist film; and

[0051] (iii) The process of developing the exposed photoresist film to form a photoresist pattern.

[0052] In the above-described photoresist pattern formation method, in step (i), a specific photoresist composition as described in this invention is selected for use.

[0053] Step (i): First, a specific photoresist composition, described later, is applied to a support using a spin coater or the like. For example, a baking (post apply bake, PAB) treatment is performed at a temperature of 80 to 150°C, preferably 80 to 120°C (more preferably 100°C) for 40 to 120 seconds, preferably 50 to 100 seconds (more preferably 60 seconds) to form a photoresist film.

[0054] Step (ii): Next, the photoresist film is selectively exposed using, for example, an exposure apparatus, by exposure of a mask (mask pattern) having a predetermined pattern, and then baked (post exposurebake, PEB) for 40 to 120 seconds, preferably 60 to 100 seconds, at a temperature of, for example, 80 to 150°C, preferably 90 to 130°C.

[0055] Step (iii): Next, the exposed photoresist film is developed. In the case of an alkaline development process, an alkaline developer is used; in the case of a solvent development process, a developer containing an organic solvent (organic developer) is used. After development, rinsing is preferably performed. 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 rinsing solution containing an organic solvent is preferred. In the case of a solvent development process, after the development or rinsing process, a process can be performed to remove the developer or rinsing solution adhering to the pattern using a supercritical fluid.

[0056] Drying is performed after development or rinsing. Alternatively, baking (post-baking) may be performed after the above development process, depending on the circumstances.

[0057] In this way, a photoresist pattern can be formed.

[0058] There are no particular limitations on the support structure; conventionally known supports can be used, such as substrates for electronic components or supports on which a specified wiring pattern is formed. More specifically, examples include silicon wafers, metal substrates made of copper, chromium, iron, aluminum, or glass substrates. For the wiring pattern material, for example, copper, aluminum, nickel, or gold can be used.

[0059] Furthermore, the support can be a support on a substrate with an inorganic and / or organic film. Examples of inorganic films include inorganic antireflective films (inorganic BARC). Examples of organic films include organic antireflective films (organic BARC) and organic films such as the lower organic film in a multilayer resist method. Here, the multilayer resist method refers to a method in which at least one additional organic film (lower organic film) and at least one additional resist film (upper resist film) are provided on a substrate, and the resist pattern formed on the upper resist film is used as a mask to pattern the lower organic film, thereby forming a pattern with a high aspect ratio. That is, according to the multilayer resist method, the required thickness can be ensured by the lower organic film, thus enabling the resist film to be thinned and fine patterns with a high aspect ratio to be formed. In the multilayer resist method, it is basically divided into a two-layer structure method that uses an upper resist film and a lower organic film (2-layer resist method); and a multilayer structure method that uses three or more layers (3-layer resist method) that sets one or more intermediate layers (such as metal thin film) between the upper resist film and the lower organic film.

[0060] The wavelength used in the 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 ray), X-rays, and soft X-rays can be used. The resist patterning method involved in this invention is particularly preferred when the KrF excimer laser is irradiated onto the resist film in step (ii).

[0061] The exposure method for the resist film can be either conventional exposure (dry exposure) in an inert gas such as air or nitrogen, or liquid immersion lithography.

[0062] Immersion exposure is an exposure method in which the space between the resist film and the lens at the bottom of the exposure apparatus is filled with a solvent (immersion medium) having a refractive index greater than that of air, and exposure is performed in this state (immersion exposure). The immersion medium is preferably a solvent having a refractive index greater than that of air and less than that of the resist film being exposed. There are no particular limitations on the refractive index of the solvent if it falls within the specified range. Examples of solvents having a refractive index greater than that of air and less than that of the resist film include water, fluorine-based inert liquids, silicon-based solvents, and hydrocarbon solvents. Specific examples of fluorine-based inert liquids include liquids with fluorine compounds such as C3HCl2F5, C4F9OCH3, C4F9OC2H5, and C5H3F7 as the main component; liquids with a boiling point of 70–180°C are preferred, and liquids with a boiling point of 80–160°C are more preferred. If the fluorine-based inert liquid has a boiling point within the aforementioned range, the medium used in the immersion solution can be removed using a simple method after exposure, which is therefore preferable. As a fluorine-based inert liquid, perfluoroalkyl compounds obtained by replacing all hydrogen atoms of the alkyl group with fluorine atoms are particularly preferred. Specifically, examples of perfluoroalkyl compounds include perfluoroalkyl ether compounds or perfluoroalkylamine compounds. Furthermore, examples of perfluoroalkyl ether compounds include perfluoro(2-butyltetrahydrofuran) (boiling point 102°C), and examples of perfluoroalkylamine compounds include perfluorotributylamine (boiling point 174°C). From the viewpoints of cost, safety, environmental issues, and versatility, water is preferred as the immersion medium.

[0063] An example of an alkaline developing solution used in alkaline developing processes is a 0.1 to 10% by mass aqueous solution of tetramethylammonium hydroxide (TMAH).

[0064] The organic solvent contained in the organic developer used in the solvent-based developing process can be any organic solvent capable of dissolving component (A) (component (A) before exposure) as described later, and can be appropriately selected from known organic solvents. Details related to the solvent are described in detail in the following description of the resist composition.

[0065] The developing process can be carried out using known developing methods, such as immersing the support in the developing solution for a certain time (immersion method), bearing the developing solution on the surface of the support by surface tension and letting it remain still for a certain time (puddle method), spraying the developing solution onto the surface of the support (spraying method), and continuously applying the developing solution onto the support rotating at a certain speed while scanning the nozzle at a certain speed (dynamic distribution method), etc.

[0066] The organic solvent contained in the rinsing solution used for rinsing after development in the solvent-based developing process can be, for example, an organic solvent that is difficult to dissolve the resist pattern, such as those exemplified as organic solvents used in organic-based developers. Known additives can be added to the rinsing solution as needed. Surfactants can be, for example, used as additives. The surfactant is preferably a nonionic surfactant, more preferably a nonionic fluorinated surfactant or a nonionic silicone surfactant. When a surfactant is added, its amount relative to the total amount of the rinsing solution is typically 0.001 to 5% by mass, preferably 0.005 to 2% by mass, more preferably 0.01 to 0.5% by mass.

[0067] Rinsing treatment (cleaning treatment) using rinsing solution can be carried out using known rinsing methods. Examples of such rinsing methods include continuously applying rinsing solution onto a support rotating at a certain speed (spin coating), immersing the support in rinsing solution for a certain time (immersion method), and spraying rinsing solution onto the surface of the support (spraying method).

[0068] Photoresist Composition

[0069] In the photoresist pattern forming method of the present invention described above, a specific photoresist composition is used in step (i). The specific photoresist composition involved in the present invention is a photoresist composition that generates acid upon exposure, and whose solubility in the developer changes due to the action of the acid. It is a photoresist composition containing a resin (A) whose solubility in the developer changes due to the action of the acid, an acid-generating agent (B) that generates acid upon exposure, a photodegradable alkali (D1), a solvent (S), and a compound (X).

[0070] The photoresist composition of the present invention contains a substrate component (A) whose solubility in the developer varies with the action of acid (hereinafter referred to as resin (A)).

[0071] <Resin(A)>

[0072] In this invention, the photoresist composition contains a resin (A) whose solubility in the developer changes due to the action of an acid (hereinafter also referred to as "component (A)"). Component (A) of this invention is soluble in the solvent (S) described later, and there is no particular limitation as long as it is a component that can be used in the photolithography process. A resin whose solubility in the developer changes due to the action of an acid is particularly preferred. After the resin whose solubility in the developer changes due to the action of an acid is mixed with the acid-generating agent (B) described later into the photoresist composition, the formed film is selectively exposed, thereby making the exposed or unexposed portions of the film selectively soluble with alkali. In this case, by contacting the selectively exposed film with an alkaline developer to remove the exposed or unexposed portions, a pattern of a desired shape can be formed.

[0073] In this invention, resin (A) contains resin (A1) (hereinafter also referred to as "(A1) component").

[0074] The resin (A1) preferably comprises structural units (a10) represented by the general formula (a10-1) described later and structural units (a10) derived from styrene. st ) resin.

[0075] (Structural unit (a10))

[0076] The structural unit (a10) is represented by the following formula (a10-1).

[0077] [Chemistry 2]

[0078]

[0079] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a haloalkyl group having 1 to 5 carbon atoms, Ya] x1 Wa is a single bond or a divalent linker. x1 For (n ax1 +1) valence aromatic hydrocarbon group, n ax1 [Integers from 1 to 3.]

[0080] In the formula (a10-1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a haloalkyl group having 1 to 5 carbon atoms.

[0081] The alkyl group having 1 to 5 carbon atoms in R is preferably a straight-chain or branched alkyl group having 1 to 5 carbon atoms. Examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, etc.

[0082] The alkyl halogroup R, having 1 to 5 carbon atoms, is a group obtained by substituting some or all of the hydrogen atoms of the alkyl halogroup having 1 to 5 carbon atoms with halogen atoms. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being particularly preferred. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluoroalkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is most preferred.

[0083] In the above formula (a10-1), Ya x1 It is a single bond or a divalent linker.

[0084] As Ya x1 The divalent linking group in the linking group is preferably a divalent hydrocarbon group having a substituent or a divalent linking group containing a heteroatom.

[0085] Divalent hydrocarbon groups that may have substituents: in Ya x1 In the case of a divalent hydrocarbon group that may have substituents, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0086] In Ya x1 In this context, aliphatic hydrocarbon groups represent hydrocarbon groups that do not possess aromaticity. The aliphatic hydrocarbon groups can be either saturated or unsaturated, but are preferably saturated.

[0087] Examples of aliphatic hydrocarbon groups include straight-chain or branched aliphatic hydrocarbon groups, or aliphatic hydrocarbon groups containing rings in their structure.

[0088] The number of carbon atoms in the straight-chain or branched aliphatic hydrocarbon groups is preferably 1 to 10, more preferably 1 to 6, further preferably 1 to 4, and most preferably 1 to 3.

[0089] As a straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred. Specifically, examples include methylene [-CH2-], ethylene [-(CH2)2-], propylene [-(CH2)3-], butylene [-(CH2)4-], and pentylene [-(CH2)5-].

[0090] The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6, further preferably 3 or 4, and most preferably 3.

[0091] As a branched aliphatic hydrocarbon group, a branched alkylene group is preferred. Specifically, examples include alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkylpropylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkyl alkylene group is preferably a straight-chain alkyl group having 1 to 5 carbon atoms.

[0092] The straight-chain or branched aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include fluorine atoms, fluoroalkyl groups with 1 to 5 carbon atoms substituted by fluorine atoms, and carbonyl groups.

[0093] Examples of alicyclic hydrocarbon groups containing rings in the aforementioned structure include alicyclic hydrocarbon groups (groups obtained by removing two hydrogen atoms from an alicyclic hydrocarbon ring), groups formed by bonding an alicyclic hydrocarbon group to the end of a straight-chain or branched alicyclic hydrocarbon group, and groups where the alicyclic hydrocarbon group is intermediate between straight-chain and branched alicyclic hydrocarbon groups. Examples of straight-chain or branched alicyclic hydrocarbon groups are the same alicyclic hydrocarbon groups as described above.

[0094] The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12.

[0095] The alicyclic hydrocarbon group can be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing two hydrogen atoms from a monocyclic alkane. As the monocyclic alkane, it is preferably a monocyclic alkane with 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. As a polycyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing two hydrogen atoms from a polycyclic alkane, specifically a polycyclic alkane with 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.

[0096] Alicyclic hydrocarbon groups may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, haloalkyl groups, hydroxyl groups, and carbonyl groups. The alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, most preferably methyl, ethyl, propyl, n-butyl, or tert-butyl. The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, or tert-butoxy, most preferably methoxy or ethoxy. Examples of halogen atoms are fluorine, chlorine, bromine, or iodine atoms, with fluorine atoms being preferred. Examples of haloalkyl groups are groups obtained by substituting some or all of the hydrogen atoms of the alkyl group with the halogen atom. A portion of the carbon atoms constituting the ring structure of a cyclic aliphatic hydrocarbon group may also be replaced by a substituent containing a heteroatom. As the substituents containing heteroatoms, -O-, -C(=O)-O-, -S-, -S(=O)2-, and -S(=O)2-O- are preferred.

[0097] Ya x1 The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system with 4n+2 π electrons; it can be polycyclic or monocyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, further preferably 6 to 15, and particularly preferably 6 to 12. The number of carbon atoms does not include the number of carbon atoms in the substituents. Examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles obtained by substituting a portion of the carbon atoms constituting the aromatic hydrocarbon ring with heteroatoms.

[0098] Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. More specifically, examples of aromatic heterocycles include pyridine rings and thiophene rings. More specifically, examples of aromatic hydrocarbon groups include groups obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (aryl or heteroaryl); groups obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups obtained by replacing one hydrogen atom of an aryl or heteroaryl group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl or heteroaryl) with an alkylene group (e.g., groups obtained by further removing one hydrogen atom from an aryl group in arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.). The alkylene group bonded to the aryl or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2, and particularly preferably 1.

[0099] The aromatic hydrocarbon group may also have its hydrogen atom replaced by a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be replaced by a substituent. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, haloalkyl groups, and hydroxyl groups.

[0100] The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably methyl, ethyl, propyl, n-butyl, or tert-butyl. Examples of substituents, such as alkoxy groups, halogen atoms, and haloalkyl groups, can be exemplified as substituents replacing hydrogen atoms in the cyclic aliphatic hydrocarbon group.

[0101] Divalent linking groups containing heteroatoms: in Ya x1 In the case of a divalent linking group containing a heteroatom, examples of such linking groups include -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted by alkyl, acyl, or other substituents), -S-, -S(=O)2-, -S(=O)2-O-, and those with the general formula -Y 21 -OY 22 -、-Y 21 -O-、-Y 21 -C(=O)-O-、-C(=O)-OY 21 -、-[Y 21 -C(=O)-O] m” -Y 22 -、-Y 21 -OC(=O)-Y 22 -or-Y 21 -S(=O)2-OY 22 - represents a group [where Y is a group that represents ... 21 and Y 22 Each group is independently a divalent hydrocarbon group that may have substituents, where O is an oxygen atom and m" is an integer from 0 to 3. These are preferred groups.

[0102] When the divalent linking group containing the heteroatom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, or -NH-C(=NH)-, the H group can be substituted with alkyl, acyl, or other substituents. The substituent (alkyl, acyl, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5. General formula -Y 21 -OY 22 -、-Y 21 -O-、-Y 21 -C(=O)-O-、-C(=O)-OY 21 -、-[Y 21-C(=O)-O] m” -Y 22 -、-Y 21 -OC(=O)-Y 22 -or-Y 21 -S(=O)2-OY 22 -Medium,Y 21 and Y 22 Each is independently a divalent hydrocarbon group that may have substituents. Examples of such divalent hydrocarbon groups include those listed in the description of the divalent linking groups (divalent hydrocarbon groups that may have substituents). As Y 21 Preferably, it is a straight-chain aliphatic hydrocarbon group, more preferably a straight-chain alkylene group, even more preferably a straight-chain alkylene group having 1 to 5 carbon atoms, and particularly preferably methylene or ethylene. As Y 22 Preferably, the aliphatic hydrocarbon group is linear or branched, more preferably methylene, ethylene, or alkylmethylene. The alkyl group in the alkylmethylene group is preferably a linear alkyl group with 1 to 5 carbon atoms, more preferably a linear alkyl group with 1 to 3 carbon atoms, and most preferably methyl. 21 -C(=O)-O] m” -Y 22 In the group represented by -, m” is an integer from 0 to 3, preferably an integer from 0 to 2, more preferably 0 or 1, and particularly preferably 1. That is, as a group represented by the formula -[Y 21 -C(=O)-O] m” -Y 22 - represents a group, particularly preferably represented by the formula -Y 21 -C(=O)-OY 22 - represents a group. Preferably, it is represented by the formula -(CH2). a’ -C(=O)-O-(CH2) b’ - represents a group. In the formula, a' is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, further preferably 1 or 2, and most preferably 1. b' is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, further preferably 1 or 2, and most preferably 1.

[0103] As Ya x1 Preferably, it is a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a -C(=O)-NH-, a straight-chain or branched alkylene group, or a combination thereof, with single bonds being particularly preferred.

[0104] In the aforementioned formula (a10-1), Wa x1 For (n ax1 +1) valence aromatic hydrocarbon group.

[0105] As Wa x1Aromatic hydrocarbon groups in the aromatic ring can be exemplified by removing (n) from the aromatic ring. ax1 A group obtained by adding 1+1 hydrogen atoms. There are no particular limitations on the aromatic ring here if it is a cyclic conjugated system with 4n+2 π electrons; it can be either monocyclic or polycyclic.

[0106] The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles obtained by replacing a portion of the carbon atoms constituting the aromatic hydrocarbon ring with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0107] In the aforementioned formula (a10-1), n ax1 It is an integer from 1 to 3, preferably 1 or 2, and more preferably 1. Hereinafter, specific examples of structural units represented by the general formula (a10-1) are shown. In the following formulas, R... α It represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0108] [Chemistry 3]

[0109]

[0110]

[0111] The structural unit (a10) of component (A1) can be one or more types.

[0112] The structural unit (a10) is preferably a structural unit containing a hydroxyl styrene skeleton, and is particularly preferred to be a structural unit represented by the following general formula (a10-1-0).

[0113] [Chemistry 4]

[0114]

[0115] [In the formula, R] st This represents a hydrogen atom or a methyl group. m 01 Represents integers from 1 to 3.

[0116] The proportion of structural unit (a10) in component (A1) relative to the total (100 mol%) of all structural units constituting component (A1) is preferably 55 to 95 mol%, more preferably 60 to 90 mol%, and particularly preferably 65 to 85 mol%.

[0117] By setting the ratio of the structural unit (a10) above the lower limit of the preferred range, the sensitivity, development characteristics, and effect of suppressing defect generation are further improved. On the other hand, by setting it below the upper limit of the preferred range, the lithographic characteristics such as size uniformity are further improved.

[0118] (structural unit (a) st ))

[0119] (A1) components can also have structural units derived from styrene (a st Structural unit (a) st The "structural unit derived from styrene" in the text refers to a structural unit formed by the cleavage of olefinic double bonds in styrene and styrene derivatives (excluding hydroxystyrene).

[0120] The term "styrene derivatives" here refers to compounds obtained by replacing the hydrogen atom of styrene bonded to the α-position with other substituents such as halogen atoms, alkyl groups, and haloalkyl groups, as well as compounds in which the hydrogen atom of the phenyl group of styrene is replaced with substituents such as lower alkyl groups having 1 to 5 carbon atoms.

[0121] Examples of halogen atoms include chlorine atoms, fluorine atoms, and bromine atoms, with fluorine atoms being preferred.

[0122] In addition, unless otherwise specified, "α-position of styrene" refers to the carbon atom bonded to the benzene ring.

[0123] As a structural unit (a st The structural units contained therein can preferably be exemplified by the following general formula (a st -1) represents the structural unit (a st 1).

[0124] [Chemistry 5]

[0125]

[0126] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a haloalkyl group having 1 to 5 carbon atoms; R] 2 This indicates an alkyl group with 1 to 5 carbon atoms; q represents 0 or an integer from 1 to 2.

[0127] R can be the same group as R in the general formula (a10-1).

[0128] q is an integer from 0 to 2. Preferably, q is 0 or 1, and particularly in industry, 0 is preferred.

[0129] When q is 1, R 2The substitution position can be any of the adjacent (o-position), intermediate (m-position), or opposite (p-position). When q is 2, any substitution position can be combined.

[0130] As a structural unit (a st It is possible to use one type or two or more types in combination.

[0131] The (A1) component contains structural unit (a) st In the case of ), structural unit (a) st The proportion of (A1) relative to all structural units constituting component (A1) is preferably 1 to 25 mol%, more preferably 5 to 25 mol%, and most preferably 10 to 25 mol%. Within this range, the heat resistance effect is improved when preparing a photoresist composition, while maintaining good balance with other structural units.

[0132] Without impairing the effects of the present invention, component (A1) may include the aforementioned essential structural unit (a10) and structural unit (a... st Other structural units besides ).

[0133] As the structural unit, any unit that is not classified as a mandatory structural unit (a10) or structural unit (a10) as described above is acceptable. st Other structural units are not particularly limited, and various structural units known to be used as photoresist resins for KrF excimer lasers, ArF excimer lasers, etc., can be used.

[0134] In this invention, component (A1) may further include the following structural units: structural unit (a1)', containing an acid-decomposing group whose polarity increases through the action of an acid; structural unit (a2)', containing a lactone cyclic group, a carbonate cyclic group, or a -SO2- cyclic group (excluding structural units belonging to the above structural unit (a1)'); structural unit (a3)', containing an aliphatic hydrocarbon group containing a polar group (excluding structural units belonging to the above structural units (a1)' and (a2)'); structural unit (a4)', containing an acid-non-dissociable cyclic group.

[0135] (Structural unit (a1)')

[0136] The structural unit (a1)' is a structural unit containing an acid-decomposing group whose polarity increases through the action of an acid.

[0137] "Acid-decomposable group" is a group whose structure has at least some of the bonds that can be broken under the action of acid.

[0138] As acid-decomposing groups that increase in polarity through the action of acids, examples can be given of groups that decompose through the action of acids to generate polar groups.

[0139] Examples of polar groups include carboxyl, hydroxyl, amino, and sulfonic acid groups (-SO3H). Among these, sulfonic acid groups or polar groups containing -OH in their structure (hereinafter sometimes referred to as "OH-containing polar groups") are preferred, and sulfonic acid groups, carboxyl groups, or hydroxyl groups are preferred, with carboxyl or hydroxyl groups being particularly preferred.

[0140] More specifically, examples of acid-dissociable groups include those polar groups protected by acid-dissociable groups (e.g., groups whose hydrogen atoms of OH-containing polar groups are protected by acid-dissociable groups).

[0141] Here, "acid-dissociable groups" refers to the following two:

[0142] (i) an acid-dissociable group that, through the action of an acid, can break the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group, or

[0143] (ii) A group in which a portion of the bonds are broken by the action of an acid, and then a decarboxylation reaction occurs, thereby breaking the bond between the acid-dissociated group and the atom adjacent to the acid-dissociated group.

[0144] The acid-dissociating groups constituting the acid-dissociating groups must be of lower polarity than the polar groups generated through the dissociation of these acid-dissociating groups. Therefore, when these acid-dissociating groups dissociate under the action of acid, they generate polar groups with higher polarity than the original acid-dissociating groups, thus increasing the overall polarity of the (A1) component. This increased polarity leads to a relative change in the solubility in the developer, decreasing solubility when the developer is organic.

[0145] There are no particular limitations on the acid-dissociable group; any group proposed that uses the acid-dissociable groups of the matrix resins currently used as photoresists can be used.

[0146] As an acid-dissociating group that protects the carboxyl or hydroxyl group in the polar group, examples can be given of acid-dissociating groups represented by the following formula (a1-r-1)' (hereinafter also referred to as "acetal-type acid-dissociating groups" for convenience).

[0147] [Chemistry 6]

[0148]

[0149] [In the formula, Ra'] 1 Ra' 2 Ra' represents a hydrogen atom or an alkyl group. 3 Ra' represents a hydrocarbon group.3 Can be with Ra' 1 Ra' 2 A ring is formed by any one of the bonds. * indicates the bond position.

[0150] In the formula (a1-r-1)', Ra' is used as... 1 Ra' 2 The alkyl group can be exemplified as the same alkyl group exemplified in the description of the α-substituted acrylate as a substituent that can bond to the carbon atom at the α-position, preferably methyl or ethyl, most preferably methyl.

[0151] As Ra' 3 The hydrocarbon group is preferably an alkyl group with 1 to 20 carbon atoms, more preferably an alkyl group with 1 to 10 carbon atoms, and preferably a straight-chain or branched alkyl group. Specifically, examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, 1,1-dimethylethyl, 1,1-diethylpropyl, 2,2-dimethylpropyl, 2,2-dimethylbutyl, etc.

[0152] In Ra' 3 When the hydrocarbon group is cyclic, it can be aliphatic or aromatic; furthermore, it can be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing one hydrogen atom from a monocyclic alkane. As this monocyclic alkane, it is preferably a monocyclic alkane with 3 to 8 carbon atoms; examples include cyclopentane, cyclohexane, and cyclooctane. As a polycyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing one hydrogen atom from a polycyclic alkane; as this polycyclic alkane, it is preferably a polycyclic alkane with 7 to 12 carbon atoms; examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0153] In Ra' 3 In the case of aromatic hydrocarbon groups, the aromatic rings contained therein can be specifically exemplified by aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles are obtained by replacing part of the carbon atoms constituting the above-mentioned aromatic hydrocarbon rings with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms.

[0154] Specifically, examples of this aromatic hydrocarbon group include groups (aryl) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring; and groups obtained by replacing one hydrogen atom of the aryl group with an alkylene group (e.g., benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc., arylalkyl groups). The alkylene group (the alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2, and particularly preferably 1.

[0155] Ra'3 With Ra' 1 Ra' 2 When a ring is formed by bonding any one of the elements, the cyclic group is preferably a four- to seven-membered ring, more preferably a four- to six-membered ring. Specific examples of this cyclic group include tetrahydropyranyl and tetrahydrofuranyl.

[0156] As an acid-dissociating group that protects the carboxyl group in the above-mentioned polar groups, examples of acid-dissociating groups represented by the following formula (a1-r-2)' can be cited (sometimes, for convenience, the group composed of alkyl groups in the acid-dissociating group represented by the following formula (a1-r-2)' is called a "tertiary alkyl ester type acid-dissociating group").

[0157] [Chemistry 7]

[0158]

[0159] [In the formula, Ra'] 4 ~Ra' 6 It is a hydrocarbon group, Ra' 5 Ra' 6 They can bond together to form a ring.

[0160] * indicates the bonding location.

[0161] As Ra' 4 ~Ra' 6 Hydrocarbon groups, for example, can be related to the above Ra' 3 The same hydrocarbon group. Ra' 4 Alkyl groups with 1 to 5 carbon atoms are preferred. In Ra' 5 With Ra' 6 When they bond together to form a ring, examples can be given by groups represented by the following formula (a1-r2-1)'.

[0162] On the other hand, in Ra' 4 ~Ra' 6 In the case where the hydrocarbon groups are independent of each other and are not bonded to each other, groups represented by the following formula (a1-r2-2)' can be cited as examples.

[0163] [Chemistry 8]

[0164]

[0165] [In the formula, Ra'] 10 Ra' represents an alkyl group having 1 to 10 carbon atoms. 11 Indicates Ra' 10 The bonded carbon atoms together form an aliphatic cyclic group, Ra' 12 ~Ra' 14 Each hydrocarbon group is represented independently. * indicates a bond position.

[0166] In the formula (a1-r2-1)', Ra' 10 The alkyl group having 1 to 10 carbon atoms is preferably Ra' in formula (a1-r-1)'. 3 Examples of linear or branched alkyl groups. In formula (a1-r2-1)', Ra' 11 The aliphatic cyclic group formed is preferably Ra' in formula (a1-r-1)'. 3 Examples of cyclic alkyl groups.

[0167] In the formula (a1-r2-2)', Ra' 12 and Ra' 14 Alkyl groups having 1 to 10 carbon atoms are preferred individually, and the alkyl group is more preferably Ra' in formula (a1-r-1)'. 3 Examples of linear or branched alkyl groups, more preferably linear alkyl groups having 1 to 5 carbon atoms, particularly preferably methyl or ethyl.

[0168] In the formula (a1-r2-2)', Ra' 13 Ra' is preferably represented as Ra' in the formula (a1-r-1)'. 3 Examples of alkyl groups include straight-chain, branched, or cyclic alkyl groups. Among these, Ra' is more preferred. 3 Cyclic alkyl groups, exemplified by [example group].

[0169] The following are specific examples of the formula (a1-r2-1)'. * indicates the bonding position.

[0170] [Chemistry 9]

[0171]

[0172]

[0173] The following are specific examples of the formula (a1-r2-2)'. * indicates the bonding position.

[0174] [Chemistry 10]

[0175]

[0176] Furthermore, as an acid-dissociating group that protects the hydroxyl group in the polar group, an example of an acid-dissociating group represented by the following formula (a1-r-3)' can be cited (hereinafter also referred to as "tertiary alkoxycarbonyl acid-dissociating group" for ease of explanation).

[0177] [Chemistry 11]

[0178]

[0179] [In the formula, Ra'] 7 ~Ra' 9 Indicates an alkyl group. * indicates the bond position.

[0180] In formula (a1-r-3)', Ra' 7 ~Ra' 9 The alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms.

[0181] Furthermore, the total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0182] Examples of structural units (a1)' include: acrylate-derived structural units from which hydrogen atoms bonded to the carbon atom at the α-position can be substituted by substituents, and structural units containing acid-degrading groups whose polarity increases through the action of acids; structural units from which at least a portion of the hydrogen atoms in the hydroxyl groups of a structural unit derived from hydroxystyrene or hydroxystyrene derivatives are protected by substituents containing the acid-degrading groups; and structural units from which at least a portion of the hydrogen atoms in the -C(=O)-OH group of a structural unit derived from vinylbenzoic acid or vinylbenzoic acid derivatives are protected by substituents containing the acid-degrading groups, etc.

[0183] As a structural unit (a1)', among the above structural units, it is preferable to be an acrylate-derived structural unit in which the hydrogen atom bonded to the carbon atom at the α position can be replaced by a substituent.

[0184] As a structural unit (a1)', it is preferred to use a structural unit represented by the following formula (a1-1)' or (a1-2)'.

[0185] [Chemistry 12]

[0186]

[0187] [In the formula, R' is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a haloalkyl group having 1 to 5 carbon atoms. Va] 1 It can be a divalent hydrocarbon group that has an ether bond, an urethane bond, or an amide bond, n a1 Ra is between 0 and 2. 1 These are acid-dissociable groups represented by the formulas (a1-r-1)' to (a1-r-2)'. 1 For n a2 +1 valence hydrocarbon group, n a2 Ra is 1 to 3. 2 This refers to an acid-dissociable group represented by the formula (a1-r-1)' or (a1-r-3)'.

[0188] In formula (a1-1)', the alkyl group having 1 to 5 carbon atoms is preferably a straight-chain or branched alkyl group having 1 to 5 carbon atoms. Examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, etc. The haloalkyl group having 1 to 5 carbon atoms is a group obtained by substituting some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms with halogen atoms. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc., with fluorine atoms being particularly preferred.

[0189] R' is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluoroalkyl group having 1 to 5 carbon atoms. From the viewpoint of industrial availability, a hydrogen atom or a methyl group is most preferred.

[0190] Va 1 The hydrocarbon group can be either aliphatic or aromatic. Aliphatic hydrocarbon groups represent hydrocarbon groups that are not aromatic. As Va... 1 The aliphatic hydrocarbon group of the divalent hydrocarbon group can be saturated or unsaturated, but saturated aliphatic hydrocarbon groups are usually preferred.

[0191] More specifically, examples of aliphatic hydrocarbon groups include straight-chain or branched aliphatic hydrocarbon groups and aliphatic hydrocarbon groups containing rings in their structure.

[0192] In addition, as Va 1 Examples of groups obtained by bonding the above-mentioned divalent hydrocarbon groups via ether bonds, carbamate bonds or amide bonds can be given.

[0193] The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, further preferably 1 to 4, and most preferably 1 to 3.

[0194] As a straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred. Specifically, examples include methylene [-CH2-], ethylene [-(CH2)2-], propylene [-(CH2)3-], butylene [-(CH2)4-], and pentylene [-(CH2)5-].

[0195] As a branched aliphatic hydrocarbon group, a branched alkylene group is preferred. Specifically, examples include alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkylpropylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkyl alkylene group is preferably a straight-chain alkyl group having 1 to 5 carbon atoms.

[0196] Examples of alicyclic hydrocarbon groups containing rings in the aforementioned structure include alicyclic hydrocarbon groups (groups obtained by removing two hydrogen atoms from an alicyclic hydrocarbon ring), groups formed by bonding an alicyclic hydrocarbon group to the end of a straight-chain or branched alicyclic hydrocarbon group, and groups where the alicyclic hydrocarbon group is intermediate between a straight-chain and branched alicyclic hydrocarbon groups. Examples of straight-chain or branched alicyclic hydrocarbon groups are the same alicyclic hydrocarbon groups as described above.

[0197] The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12.

[0198] The alicyclic hydrocarbon group can be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing two hydrogen atoms from a monocyclic alkane. As the monocyclic alkane, it is preferably a monocyclic alkane with 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. As a polycyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing two hydrogen atoms from a polycyclic alkane. As the polycyclic alkane, it is preferably a polycyclic alkane with 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.

[0199] Aromatic hydrocarbon groups are hydrocarbon groups that have aromatic rings.

[0200] The Va 1 The aromatic hydrocarbon group, which is a divalent hydrocarbon group, preferably has 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. This number of carbon atoms does not include the number of carbon atoms in the substituents.

[0201] Aromatic rings, which are present in aromatic hydrocarbon groups, can specifically be exemplified by aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles, which are formed when a portion of the carbon atom constituting the aromatic hydrocarbon ring is replaced by a heteroatom. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms.

[0202] Specifically, examples of this aromatic hydrocarbon group include groups (arylenes) obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring; groups (aryl groups) obtained by replacing one hydrogen atom of an aryl group (aryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring with an alkylene group (for example, groups obtained by removing one hydrogen atom from an aryl group in arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.). The alkylene group (the alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2, and particularly preferably 1.

[0203] In the aforementioned formula (a1-2)', Wa 1 n a2 The +1 valence hydrocarbon group can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. This aliphatic hydrocarbon group represents a hydrocarbon group that is not aromatic; it can be saturated or unsaturated, but is generally preferred to be saturated. Examples of the aliphatic hydrocarbon group include straight-chain or branched aliphatic hydrocarbon groups, aliphatic hydrocarbon groups containing a ring in their structure, or groups obtained by combining straight-chain or branched aliphatic hydrocarbon groups with aliphatic hydrocarbon groups containing a ring in their structure. Specifically, examples include Va... 1 The same group.

[0204] The n a2 The +1 valence is preferably 2 to 4 valences, and more preferably 2 or 3 valences.

[0205] As for the aforementioned formula (a1-2)', the structural unit represented by the following formula (a1-2-01)' is particularly preferred.

[0206] [Chemistry 13]

[0207]

[0208] In formula (a1-2-01)', Ra 2 It is an acid-dissociable group represented by the formula (a1-r-1)' or (a1-r-3)'. a2 It is an integer from 1 to 3, preferably 1 or 2, more preferably 1. c is an integer from 0 to 3, preferably 0 or 1, more preferably 1. R' is the same as above.

[0209] The following are specific examples of the given formulas (a1-1)' and (a1-2)'. In the following formulas, R αIt represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0210] [Chemistry 14]

[0211]

[0212]

[0213]

[0214] When the (A1) component has structural unit (a1)', the proportion of structural unit (a1)' in the (A1) component relative to the total of all structural units constituting the (A1) component is preferably 3 to 25 mol%, more preferably 5 to 20 mol%. By keeping the above proportion above the lower limit, lithographic characteristics such as sensitivity, resolution, and LWR are also improved. Furthermore, by keeping the above proportion below the upper limit, a balance with other structural units can be achieved.

[0215] (Structural unit (a2)')

[0216] In this invention, the (A1) component may contain a structural unit (a2)', which has a heterocyclic group containing a -SO2- cyclic group, a lactone cyclic group, a carbonate cyclic group, or other heterocyclic groups.

[0217] The -SO2- cyclic group, lactone cyclic group, carbonate cyclic group or other heterocyclic group of the structural unit (a2)' are effective in improving the adhesion of the photoresist film to the support.

[0218] In addition, if structural unit (a1)' has a heterocyclic group containing -SO2-, lactone, carbonate or other heterocyclic groups in its structure, the structural unit also belongs to structural unit (a2)', but such structural unit is a structural unit belonging to structural unit (a1)' but not structural unit (a2)'.

[0219] The structural unit (a2)' is preferably a structural unit represented by the following formula (a2-1)'.

[0220] [Chemistry 15]

[0221]

[0222] [In the formula, R' is a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, or a haloalkyl group with 1 to 5 carbon atoms, Ya] 21 La is a single-bonded or divalent linking group. 21The denoted as -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, where R' represents a hydrogen atom or a methyl group. Specifically, in La... 21 In the case of -O-, Ya 21 It can't be -CO-. Ra 21 It can be a heterocyclic group containing a -SO2- cyclic group, a lactone cyclic group, a carbonate cyclic group, or other heterocyclic groups.

[0223] In the above formula (a2-1)', Ra 21 Preferably, it contains a -SO2- cyclic group, a lactone cyclic group, a heterocyclic group, or a carbonate cyclic group.

[0224] "-SO2-containing cyclic group" refers to a cyclic group whose ring skeleton contains a ring containing -SO2-. Specifically, it is a cyclic group in which the sulfur atom (S) in -SO2- forms part of the ring skeleton of the cyclic group. In this ring skeleton, the ring containing -SO2- is counted as the first ring. If it contains only this ring, it is called a monocyclic group. If it has other ring structures, regardless of their structure, it is called a polycyclic group. A -SO2-containing cyclic group can be either a monocyclic or polycyclic group.

[0225] The -SO2- cyclic group is particularly preferred to be a cyclic group whose ring skeleton contains -O-SO2-, that is, a cyclic group containing a sulfonyl lactone ring in which -OS- in -O-SO2- forms part of the ring skeleton. More specifically, groups represented by the following formulas (a5-r-1)' to (a5-r-4)' can be cited as -SO2- cyclic groups.

[0226] [Chemistry 16]

[0227]

[0228] [In the formula, Ra'] 51 Each of these can be independently a hydrogen atom, alkyl group, alkoxy group, halogen atom, haloalkyl group, hydroxyl group, -COOR", -OC(=O)R", hydroxyalkyl group, or cyano group; R" is a hydrogen atom or alkyl group; A" is an alkylene group, oxygen atom, or sulfur atom with 1 to 5 carbon atoms, which may contain oxygen or sulfur atoms; n' is an integer from 0 to 2. * indicates the bonding position.

[0229] In the formulas (a5-r-1)' to (a5-r-4)', A” is the same as A” in the formulas (a2-r-1)' to (a2-r-7)' described later. As Ra' 51 The alkyl, alkoxy, halogen atom, haloalkyl, -COOR", -OC(=O)R", and hydroxyalkyl groups mentioned in the following formulas (a2-r-1)'~(a2-r-7)' are similar to Ra'.21 same.

[0230] The following are specific examples of groups represented by formulas (a5-r-1)' to (a5-r-4)'. In these formulas, "Ac" represents an acetyl group. * indicates the bonding position.

[0231] [Chemistry 17]

[0232]

[0233]

[0234] In this invention, when the structural unit (a2)' contains a -SO2-cyclic group, there is no particular limitation if the logP value of the acrylate monomer containing the -SO2-cyclic group is less than 1.2. However, among the above, it is preferred to use a group represented by the formula (a5-r-1)', more preferably at least one group selected from the group represented by any one of the formulas (r-sl-1-1), (r-sl-1-18), (r-sl-3-1) and (r-sl-4-1), and most preferably a group represented by the formula (r-sl-1-1).

[0235] "Lactone-containing cyclic group" indicates a cyclic group whose ring skeleton contains a ring containing -OC (=O)- (lactone ring). The lactone ring is designated as the first ring. In the case of only a lactone ring, it is called a monocyclic group; in the case of other ring structures, regardless of their structure, it is called a polycyclic group. Lactone-containing cyclic groups can be either monocyclic or polycyclic.

[0236] There are no particular limitations on the lactone-containing cyclic group; any lactone-containing cyclic group can be used. Specifically, groups represented by the following formulas (a2-r-1)' to (a2-r-7)' can be cited as examples. * indicates the bonding position.

[0237] [Chemistry 18]

[0238]

[0239] [In the formula, Ra'] 21 Each of these can be independently a hydrogen atom, alkyl group, alkoxy group, halogen atom, haloalkyl group, hydroxyl group, -COOR", -OC(=O)R", hydroxyalkyl group, or cyano group; R" is a hydrogen atom or alkyl group; A" is an alkylene group, oxygen atom, or sulfur atom with 1 to 5 carbon atoms, which may contain oxygen or sulfur atoms; n' is an integer from 0 to 2; and m' is 0 or 1.

[0240] In the formulas (a2-r-1)' to (a2-r-7)', A” is an alkylene group with 1 to 5 carbon atoms, which may contain an oxygen atom (-O-) or a sulfur atom (-S-). As the alkylene group with 1 to 5 carbon atoms in A”, a straight-chain or branched alkylene group is preferred, and examples include methylene, ethylene, n-propylene, and isopropylene. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples include groups with -O- or -S- intermediates at the end of the alkylene group or between carbon atoms, such as -O-CH2-, -CH2-O-CH2-, -S-CH2-, and -CH2-S-CH2-. As A”, an alkylene group with 1 to 5 carbon atoms or -O- is preferred, an alkylene group with 1 to 5 carbon atoms is more preferred, and methylene is most preferred. Ra' 21 Each can be independently an alkyl group, an alkoxy group, a halogen atom, a haloalkyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group.

[0241] As Ra' 21 The alkyl group in the sample is preferably an alkyl group with 1 to 5 carbon atoms.

[0242] As Ra' 21 The alkoxy group in the formula is preferably an alkoxy group having 1 to 5 carbon atoms. This alkoxy group is preferably linear or branched. Specifically, an example of Ra' can be cited. 21 The alkyl group, for example, is a group formed by attaching an alkyl group to an oxygen atom (-O-).

[0243] As Ra' 21 The halogen atoms in the atom can be fluorine, chlorine, bromine, iodine, etc., with fluorine atoms being preferred.

[0244] As Ra' 21 The haloalkyl group in it can be exemplified by Ra' 21 A group obtained by replacing some or all of the hydrogen atoms of the alkyl group with the halogen atom. The alkyl group is preferably a fluoroalkyl group, and particularly preferably a perfluoroalkyl group.

[0245] The following are specific examples of groups represented by formulas (a2-r-1)' to (a2-r-7)'. * indicates the bonding position.

[0246] [Chemistry 19]

[0247]

[0248]

[0249] In this invention, the structural unit (a2)' is preferably a group represented by the formula (a2-r-1)' or (a2-r-2)', and more preferably a group represented by the formula (r-lc-1-1) or (r-lc-2-7).

[0250] "Carbonate-containing cyclic groups" refer to cyclic groups whose ring skeleton contains a ring (carbonate ring) containing -OC (=O)-O-. The carbonate ring is designated as the first ring. In the case of only a carbonate ring, it is called a monocyclic group; in the case of other ring structures, regardless of their specific structure, it is called a polycyclic group. Carbonate-containing cyclic groups can be either monocyclic or polycyclic.

[0251] Specifically, examples can be given of groups represented by the formulas (ax3-r-1)' to (ax3-r-3)'. * indicates the bonding position.

[0252] [Chemistry 20]

[0253]

[0254] [In the formula, Ra'] x31 Each of these can be independently a hydrogen atom, alkyl group, alkoxy group, halogen atom, haloalkyl group, hydroxyl group, -COOR", -OC(=O)R", hydroxyalkyl group, or cyano group; R" is a hydrogen atom or alkyl group; A" is an alkylene group, oxygen atom, or sulfur atom with 1 to 5 carbon atoms, which may contain oxygen or sulfur atoms; q' is 0 or 1.

[0255] The specific examples of A” in the formulas (ax3-r-1)'~(ax3-r-3)' are the same as those of A” in the formulas (a2-r-1)'~(a2-r-7)'. As Ra' x31 Alkyl, alkoxy, halogen atom, haloalkyl, -COOR", -OC(=O)R", hydroxyalkyl, can be exemplified by Ra' in the formulas (a2-r-1)' to (a2-r-7)'. 21 The same groups listed in the description.

[0256] The following are specific examples of groups represented by the formulas (ax3-r-1)' to (ax3-r-3)'. * indicates the bonding position.

[0257] [Chemistry 21]

[0258]

[0259] "Heterocyclic group" refers to a cyclic group containing one or more atoms other than carbon. Examples include heterocyclic groups and nitrogen-containing heterocyclic groups listed below (r-hr-1) to (r-hr-16). As a nitrogen-containing heterocyclic group, examples include cycloalkyl groups with 3 to 8 carbon atoms that can be substituted by one or two oxo groups. Suitable examples of such cycloalkyl groups include, for instance, 2,5-dioxapyrrolidine and 2,6-dioxapiperidine. * indicates the bonding position.

[0260] [Chemistry 22]

[0261]

[0262] The following are specific examples of structural units (a2)' containing lactone ring groups. In the following formulas, R α It can be a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0263] [Chemistry 23]

[0264]

[0265] The structural unit (a2)' can be one type or two or more types.

[0266] When the (A1) component has structural unit (a2)', the proportion of structural unit (a2)' relative to the total of all structural units constituting the (A1) component is preferably 1 to 80 mol%, more preferably 3 to 70 mol%, even more preferably 5 to 65 mol%, and particularly preferably 10 to 60 mol%. By setting it to the lower limit or above, the effect of containing structural unit (a2)' can be fully obtained, and by setting it to the upper limit or below, a balance with other structural units can be achieved, resulting in good lithographic properties and pattern shapes.

[0267] (Structural unit (a3)')

[0268] Structural unit (a3)' is a structural unit containing an aliphatic hydrocarbon group with a polar group (excluding structural units belonging to the above-mentioned structural units (a1)' and (a2)').

[0269] It is believed that when component (A1) has structural unit (a3), the hydrophilicity of component (A1) is enhanced, which helps to improve resolution.

[0270] Examples of polar groups include hydroxyl, cyano, carboxyl, and hydroxyalkyl groups obtained by replacing part of the hydrogen atom of an alkyl group with a fluorine atom, with hydroxyl being particularly preferred.

[0271] Examples of aliphatic hydrocarbon groups include straight-chain or branched hydrocarbon groups (preferably alkylene groups) and cyclic aliphatic hydrocarbon groups (cyclic groups) with 1 to 10 carbon atoms. The cyclic group can be monocyclic or polycyclic, and can be appropriately selected from the cyclic groups frequently mentioned in the resins used in photoresist compositions for ArF excimer lasers. Polycyclic groups are preferred, and groups with 7 to 30 carbon atoms are more preferred.

[0272] More preferably, the structural unit is derived from an acrylate containing an aliphatic polycyclic group, wherein the aliphatic polycyclic group contains hydroxyalkyl groups obtained by substituting a portion of the hydrogen atoms of a hydroxyl, cyano, carboxyl, or alkyl group with a fluorine atom. Examples of such polycyclic groups include groups obtained by removing two or more hydrogen atoms from bicyclic alkanes, tricyclic alkanes, tetracyclic alkanes, etc. Specifically, examples include groups obtained by removing two or more hydrogen atoms from polycyclic alkanes such as adamantane, norbornene, isoboronane, tricyclic decane, and tetracyclic dodecane. Among these polycyclic groups, industrially preferred groups are those obtained by removing two or more hydrogen atoms from adamantane, those obtained by removing two or more hydrogen atoms from norbornene, and those obtained by removing two or more hydrogen atoms from tetracyclic dodecane.

[0273] As a structural unit (a3)', there are no particular restrictions as long as it contains an aliphatic hydrocarbon group with a polar group, and any structural unit can be used.

[0274] As a structural unit (a3)', it is preferably an acrylate-derived structural unit that is substituted by a substituent for the hydrogen atom bonded to the carbon atom at the α position, and is a structural unit containing an aliphatic hydrocarbon group with a polar group.

[0275] As the structural unit (a3)', when the hydrocarbon group in the aliphatic hydrocarbon group containing a polar group is a straight-chain or branched hydrocarbon group with 1 to 10 carbon atoms, it is preferably a structural unit derived from the hydroxyethyl ester of acrylic acid. When the hydrocarbon group is a polycyclic group, it is preferably a structural unit represented by the following formula (a3-1)' to formula (a3-5)', and more preferably a structural unit represented by the following formula (a3-1)'.

[0276] [Chemistry 24]

[0277]

[0278] [In the formula, R' is the same as above, j is an integer from 1 to 3, k is an integer from 1 to 3, t' is an integer from 1 to 3, l is an integer from 1 to 5, and s is an integer from 1 to 3.]

[0279] In formula (a3-1)', j is preferably 1 or 2, more preferably 1. When j is 2, it is preferred that the hydroxyl group is bonded to the 3- and 5-positions of the adamantyl alkyl group. When j is 1, it is preferred that the hydroxyl group is bonded to the 3-position of the adamantyl alkyl group.

[0280] j is preferably 1, and particularly preferably the 3-position bond between the hydroxyl group and the adamantyl group.

[0281] In formula (a3-2)', k is preferably 1. Preferably, the cyano group is bonded to the 5th or 6th position of the norborneol group.

[0282] In formula (a3-3)', t' is preferably 1. l is preferably 1. s is preferably 1. Preferably, they are bonded to the end of the carboxyl group of acrylic acid with 2-norbornyl or 3-norbornyl. The fluoroalkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

[0283] The structural unit (a3)' contained in component (A1) can be one type or two or more types.

[0284] When the (A1) component contains structural unit (a3)', the proportion of structural unit (a3)' in the (A1) component relative to the total of all structural units constituting the (A1) component is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, and even more preferably 5 to 25 mol%.

[0285] By setting the proportion of structural unit (a3)' above the lower limit, the full effect of containing structural unit (a3)' can be obtained; by setting it below the upper limit, it is easy to achieve a balance with other structural units.

[0286] In addition to the structural units (a1)', (a2)', and (a3)', component (A1) may also have the following structural unit (a4)'.

[0287] (Structural unit (a4)')

[0288] The structural unit (a4)' is a structural unit containing an acid-non-dissociable cyclic group. When the (A1) component has the structural unit (a4)', the dry etching resistance of the formed photoresist pattern is improved. Furthermore, the hydrophobicity of the (A1) component is improved. It is believed that, especially in the case of organic solvent development, the improved hydrophobicity contributes to improvements in resolution, photoresist pattern shape, etc.

[0289] The “acid-non-dissociative cyclic group” in structural unit (a4)' is a cyclic group that does not dissociate and remains directly in the structural unit even when acid is generated by component (B) described later through exposure.

[0290] As a structural unit (a4)', for example, it is preferable to be a structural unit derived from an acrylate containing an acid-non-dissociable aliphatic cyclic group. This cyclic group can be, for example, the same group exemplified in the case of the structural unit (a1)' described above, and a variety of groups known to date can be used as groups used in the resin component of photoresist compositions for ArF excimer lasers, KrF excimer lasers (preferably for ArF excimer lasers), etc.

[0291] In particular, it is preferred if the polycyclic group is selected from at least one of tricyclic decyl, adamantyl, tetracyclic dodecyl, isobornyl, and norbornyl, as it is readily available in industry. These polycyclic groups may have straight-chain or branched alkyl groups with 1 to 5 carbon atoms as substituents.

[0292] As a structural unit (a4)', specifically, a structural unit that can exemplify the structure of the following formulas (a4-1)' to (a4-7)'.

[0293] [Chemistry 25]

[0294]

[0295] [In the formula, R] α This indicates a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0296] The structural unit (a4)' contained in component (A1) can be one type or two or more types.

[0297] When the (A1) component contains structural unit (a4)', the proportion of structural unit (a4)' relative to the total of all structural units constituting the (A1) component is preferably 1 to 30 mol%, more preferably 10 to 20 mol%.

[0298] In the photoresist composition of this embodiment, component (A) can be used alone or in combination with two or more components.

[0299] In the photoresist composition of the present invention, the content of component (A) can be adjusted according to the desired characteristics of the photoresist to be formed, but is preferably 20 to 100 parts by mass relative to 100 parts by mass of component (S) described later, more preferably 40 to 80 parts by mass, and even more preferably 50 to 70 parts by mass.

[0300] <Acid-producing agent (B)>

[0301] In addition to component (A), the photoresist composition of the present invention also contains an acid-generating component (hereinafter referred to as "component (B)").

[0302] As component (B), there are no particular limitations; any acid-generating agent that has been proposed for use as a photoresist to date can be used.

[0303] Examples of acid-producing agents include onium salts such as iodonium salts and sulfonium salts; oxime sulfonates; diazomethanes such as dialkyl or diarylsulfonyl diazomethanes and poly(disulfonyl)diazomethanes; nitrobenzyl sulfonates, iminosulfonates, and disulfones. Onium salts are preferred among these.

[0304] Examples of onium salt acid-producing agents include compounds represented by formula (b-1) (hereinafter also referred to as "(b-1) component"), compounds represented by formula (b-2) (hereinafter also referred to as "(b-2) component"), or compounds represented by formula (b-3) (hereinafter also referred to as "(b-3) component").

[0305] [Chemistry 26]

[0306]

[0307] [In the formula, R] 101 R 104 and R 105 Each can be a halogen atom, a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents. R 104 R 105 They can bond together to form a ring. R 102 It is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms. R 106 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents, wherein, in R 106 In the figure, the carbon atom adjacent to the S atom has no bonded fluorine atom (no fluorine substitution). 101 It is a single bond or a divalent linker containing an oxygen atom. V 101 ~V 103 Each can be independently a single bond, an alkylene group, or a fluoroalkylene group. L 101 ~L 102 Each can be a single bond or an oxygen atom, independently. m is an integer greater than or equal to 1, M' m+ It is an m-valent ononium cation.

[0308] {Anion section}

[0309] • (b-1) Anionic portion of component

[0310] In equation (b-1), R 101It can be a halogen atom, a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents.

[0311] Examples of halogen atoms include fluorine, chlorine, bromine, and iodine, with fluorine being the preferred choice.

[0312] Cyclic groups that may have substituents:

[0313] The cyclic group is preferably a cyclic hydrocarbon group, which can be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group indicates a hydrocarbon group that is not aromatic. Furthermore, the aliphatic hydrocarbon group can be saturated or unsaturated, but is generally preferred to be saturated.

[0314] R 101 The aromatic hydrocarbon group in the form is a hydrocarbon group having an aromatic ring. The number of carbon atoms in this aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. This number of carbon atoms does not include the number of carbon atoms in the substituents.

[0315] As R 101 The aromatic rings contained in aromatic hydrocarbon groups can be specifically exemplified by benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles obtained by replacing part of the carbon atoms constituting these aromatic rings with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms.

[0316] As R 101 The aromatic hydrocarbon group in the aromatic ring can specifically include groups obtained by removing one hydrogen atom from the aromatic ring (aryl: for example, phenyl, naphthyl, etc.), and groups obtained by substituting one hydrogen atom of the aromatic ring with an alkylene group (for example, benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc., arylalkyl groups). The alkylene group (the alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2, and particularly preferably 1.

[0317] R 101 Examples of cyclic aliphatic hydrocarbon groups in the structure include aliphatic hydrocarbon groups containing rings.

[0318] Examples of alicyclic hydrocarbon groups containing a ring in the structure include alicyclic hydrocarbon groups (groups obtained by removing one hydrogen atom from an alicyclic hydrocarbon ring), alicyclic hydrocarbon groups bonded to the end of a straight-chain or branched alicyclic hydrocarbon group, and alicyclic hydrocarbon groups that are intermediate between straight-chain and branched alicyclic hydrocarbon groups.

[0319] The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12.

[0320] The alicyclic hydrocarbon group can be either a polycyclic or a monocyclic group. As a monocyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing one or more hydrogen atoms from a monocyclic alkane. As the monocyclic alkane, a monocyclic alkane with 3 to 6 carbon atoms is preferred; examples include cyclopentane and cyclohexane. As a polycyclic alicyclic hydrocarbon group, it is preferably a group obtained by removing one or more hydrogen atoms from a polycyclic alkane; as the polycyclic alkane, a polycyclic alkane with 7 to 30 carbon atoms is preferred. More preferably, as the polycyclic alkane, are polycyclic alkanes with a cross-linked ring structure such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; and polycyclic alkanes with a fused ring structure such as a cyclic group with a steroidal skeleton.

[0321] Among them, as R 101 The cyclic aliphatic hydrocarbon group in the form is preferably a group obtained by removing one or more hydrogen atoms from a monocyclic alkane or polycyclic alkane, more preferably a group obtained by removing one hydrogen atom from a polycyclic alkane, particularly preferably adamantyl or norbornyl, and most preferably adamantyl.

[0322] The linear or branched aliphatic hydrocarbon group that can be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, further preferably 1 to 4, and most preferably 1 to 3.

[0323] As a straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred. Specifically, examples include methylene [-CH2-], ethylene [-(CH2)2-], propylene [-(CH2)3-], butylene [-(CH2)4-], and pentylene [-(CH2)5-].

[0324] As a branched aliphatic hydrocarbon group, a branched alkylene group is preferred. Specifically, examples include alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkylpropylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkyl alkylene group is preferably a straight-chain alkyl group having 1 to 5 carbon atoms.

[0325] In addition, R 101The cyclic hydrocarbon groups in the formula can contain heteroatoms, similar to heterocycles. Specifically, examples include lactone-containing cyclic groups represented by formulas (a2-r-1)' to (a2-r-7)', -SO2-containing polycyclic groups represented by formulas (a5-r-1)' to (a5-r-2)', and other heterocyclic groups represented by formulas (r-hr-1) to (r-hr-16). * indicates the bonding position.

[0326] [Chemistry 27]

[0327]

[0328] As R 101 Substituents in the cyclic group can be, for example, alkyl, alkoxy, halogen atom, haloalkyl, hydroxyl, carbonyl, nitro, etc.

[0329] The alkyl group used as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably methyl, ethyl, propyl, n-butyl, or tert-butyl.

[0330] The alkoxy group used as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, or tert-butoxy, and most preferably methoxy or ethoxy.

[0331] Examples of halogen atoms that can be used as substituents include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being the preferred option.

[0332] Examples of alkyl halogens that can be used as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, tert-butyl, etc., in which some or all of the hydrogen atoms are replaced by the halogen atom.

[0333] The carbonyl group, as a substituent, is a group that replaces the methylene (-CH2-) group that constitutes the cyclic hydrocarbon group.

[0334] Alkyl groups that may have substituents:

[0335] As R 101 The chain alkyl group can be either straight-chain or branched.

[0336] As a straight-chain alkyl group, it is preferably composed of 1 to 20 carbon atoms, more preferably 1 to 15, and most preferably 1 to 10. Specifically, examples include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, isotriadecyl, tetradecyl, pentadecyl, hexadecyl, isohexadecanyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, dodecyl, and dodecyl.

[0337] As a branched alkyl group, it is preferably composed of 3 to 20 carbon atoms, more preferably 3 to 15, and most preferably 3 to 10. Specifically, examples include 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, etc.

[0338] Alkenyl groups that may have substituents in a chain-like structure:

[0339] As R 101 The chain-like alkenyl group can be either straight-chain or branched, preferably with 2 to 10 carbon atoms, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of straight-chain alkenyl groups include vinyl, allyl, and butynyl. Examples of branched alkenyl groups include 1-methylvinyl, 2-methylvinyl, 1-methylpropenyl, and 2-methylpropenyl.

[0340] As a chain-like alkenyl group, the linear alkenyl group is preferred, more preferably vinyl or propenyl, and particularly preferably vinyl.

[0341] As R 101 Substituents in the chain alkyl or chain alkenyl groups, for example, alkoxy, halogen atom, haloalkyl, hydroxy, carbonyl, nitro, amino, said R 101 Ring-shaped bases, etc.

[0342] Among them, R 101 Preferably, it is a cyclic group that may have substituents, or a chain alkyl group that may have substituents, more preferably a cyclic group that may have substituents, and even more preferably a cyclic hydrocarbon group that may have substituents.

[0343] Among these, phenyl, naphthyl, groups obtained by removing one or more hydrogen atoms from a polycyclic alkane, lactone-containing cyclic groups represented by the formulas (a2-r-1)' to (a2-r-7)' respectively, and -SO2-containing polycyclic groups represented by the formulas (a5-r-1)' to (a5-r-2)' respectively are preferred. More preferred among these are groups obtained by removing one or more hydrogen atoms from a polycyclic alkane and -SO2-containing polycyclic groups represented by the formulas (a5-r-1)' to (a5-r-2)' respectively.

[0344] In equation (b-1), Y 101 It is a single bond or a divalent linker containing an oxygen atom.

[0345] In Y 101 In the case where the Y is a divalent linking group containing an oxygen atom, 101It can contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.

[0346] Examples of non-hydrocarbon oxygen-containing linking groups that are divalent and contain an oxygen atom include oxygen atoms (ether bond: -O-), ester bond (-C(=O)-O-), oxycarbonyl group (-OC(=O)-), amide bond (-C(=O)-NH-), carbonyl group (-C(=O)-), carbonate bond (-OC(=O)-O-), etc.; combinations of these non-hydrocarbon oxygen-containing linking groups with alkylene groups, etc. In such combinations, a sulfonyl group (-SO2-) may also be further attached. Examples of such divalent oxygen-containing linking groups include linking groups represented by the following formulas (y-al-1) to (y-al-7).

[0347] [Chemistry 28]

[0348]

[0349] [In the formula, V'] 101 It is a single bond or an alkylene group with 1 to 5 carbon atoms, V' 102 It is a divalent saturated hydrocarbon group with 1 to 30 carbon atoms.

[0350] V' 102 The divalent saturated hydrocarbon group is preferably an alkylene group with 1 to 30 carbon atoms, more preferably an alkylene group with 1 to 10 carbon atoms, and even more preferably an alkylene group with 1 to 5 carbon atoms.

[0351] As V' 101 and V' 102 The alkylene groups in the form can be straight-chain alkylene groups or branched alkylene groups, with straight-chain alkylene groups being preferred.

[0352] As V' 101 and V' 102The alkylene groups in this context can specifically include methylene [-CH2-]; alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; and ethylene [-CH2CH2-]; alkylmethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, and -C(CH3)2CH2-. Alkyl ethylides such as -CH(CH2CH3)CH2-; propylene (n-propylene) [-CH2CH2CH2-]; alkyl propylenes such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; butylides [-CH2CH2CH2CH2-]; alkyl butylides such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-; pentylides [-CH2CH2CH2CH2CH2-], etc.

[0353] In addition, V' 101 or V' 102 A portion of the methylene group in the alkylene group may be replaced by a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably cyclohexylene, 1,5-adamantyl, or 2,6-adamantyl.

[0354] As Y 101 Preferably, the linking group contains a divalent ester bond or a divalent ether bond, more preferably the linking group represented by the formulas (y-al-1) to (y-al-5), and even more preferably the linking group represented by the formulas (y-al-1) to (y-al-3).

[0355] In equation (b-1), V 101 It is a single bond, an alkylene group, or a fluoroalkylene group. V 101 The alkylene or fluoroalkylene groups preferably have 1 to 4 carbon atoms. As V 101 The fluoroalkylene groups in the text can be exemplified by V. 101 A group obtained by replacing some or all of the hydrogen atoms of the alkylene group with fluorine atoms. Wherein, V 101 Preferably, it is a single bond or a fluoroalkylene group having 1 to 4 carbon atoms.

[0356] In equation (b-1), R 102 It is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms. R 102 Preferably, it is a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, more preferably a fluorine atom.

[0357] Specific examples of the anionic portion of component (b-1) include, for example, in Y 101In the case of a single bond, examples include fluoroalkyl sulfonate anions such as trifluoromethane sulfonate anion or perfluorobutane sulfonate anion; in Y 101 In the case of a divalent linking group containing an oxygen atom, anions represented by any one of the following formulas (an-1) to (an-3) can be cited.

[0358] [Chemistry 29]

[0359]

[0360] [In the formula, R”] 101 It can be an aliphatic cyclic group that may have substituents, a group represented by the formulas (r-hr-1) to (r-hr-6) respectively, or a chain alkyl group that may have substituents; R” 102 It can be an aliphatic cyclic group that may have substituents, a lactone-containing cyclic group represented by the formulas (a2-r-1)' to (a2-r-7)' respectively, or a polycyclic group containing -SO2- represented by the formulas (a5-r-1)' to (a5-r-2)' respectively; R” 103 It can be an aromatic cyclic group, an aliphatic cyclic group, or a chain alkenyl group that may have substituents; v” is an integer independently of 0 to 3, q” is an integer independently of 1 to 20, t” is an integer of 1 to 3, and n” is 0 or 1.

[0361] R” 101 、R” 102 and R” 103 The aliphatic cyclic group that may have substituents is preferably the R group. 101 Examples of substituents include cyclic aliphatic hydrocarbon groups. Examples of substituents include those related to R. 101 The same substituents are used for the substituted cyclic aliphatic hydrocarbon groups.

[0362] R” 103 The aromatic cyclic group that may have substituents is preferably the R group. 101 The group exemplified is the aromatic hydrocarbon group in the cyclic hydrocarbon group. Examples of substituents include those related to R. 101 The same substituents that can replace the aromatic hydrocarbon group in the same group.

[0363] R” 101 The substituted chain alkyl group in the R is preferably a substituent. 101 The chain alkyl group is exemplified by the group "R". 103 The chain alkenyl group that may have substituents is preferably the R group. 101 The chain-like alkenyl group is exemplified by the group.

[0364] • (b-2) Anionic portion of component

[0365] In equation (b-2), R 104 R 105 Each can be independently a halogen atom, a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents, and examples can be given for R in formula (b-1). 101 The same group. Among them, R... 104 R 105 They can bond together to form a ring.

[0366] R 104 R 105 Preferably, it is a chain alkyl group that may have substituents, more preferably a straight-chain or branched alkyl group, or a straight-chain or branched fluoroalkyl group.

[0367] The chain-like alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and even more preferably 1 to 3 carbon atoms. R also exhibits good solubility in solvents used for photoresists. 104 R 105 The number of carbon atoms in the chain alkyl group is preferably as small as possible within the range of said carbon number. Furthermore, R 104 R 105 In the chain alkyl group, the more hydrogen atoms replaced by fluorine atoms, the stronger the acid and the better the transparency to high-energy light and electron beams below 200 nm, which is therefore preferred.

[0368] The proportion of fluorine atoms in the chain-like alkyl group, i.e., the fluorination rate, is preferably 70-100%, more preferably 90-100%, and most preferably a perfluoroalkyl group obtained by replacing all hydrogen atoms with fluorine atoms.

[0369] In equation (b-2), V 102 V 103 Each can be independently a single bond, an alkylene group, or a fluoroalkylene group, and examples can be given for V in formula (b-1). 101 The same group.

[0370] In equation (b-2), L 101 L 102 Each can be a single bond or an oxygen atom, independently.

[0371] • (b-3) Anionic portion of component

[0372] In equation (b-3), R 106 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents, wherein, in R 106 In this case, the carbon atom adjacent to the S atom has no bonded fluorine atom (no fluorine substitution). R106 Preferably, it is a cyclic group that may have substituents or a chain alkyl group that may have substituents.

[0373] Specific examples of preferred anion portions of component (b-3) can be exemplified by anions (d1-2-11) to (d1-2-31) which are preferred examples of preferred anion portions of component (d1-2) in component (D) described later, with the most preferred being anion (d1-2-11).

[0374] {Cation section}

[0375] In equations (b-1), (b-2), and (b-3), m is an integer greater than or equal to 1, and M' m+ The m-valent onium cations are preferably sulfonium cations and iodonium cations, and particularly preferably organic cations represented by the following formulas (ca-1) to (ca-4).

[0376] [Chemistry 30]

[0377]

[0378] [In the formula, R] 201 ~R 207 and R 211 ~R 212 Each can independently represent an aryl, alkyl, or alkenyl group that may have substituents, R 201 ~R 203 R 206 ~R 207 R 211 ~R 212 They can bond with each other and form a ring together with the sulfur atoms in the formula. R 208 ~R 209 Each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R 210 It can be an aryl group that may have a substituent, an alkyl group that may have a substituent, an alkenyl group that may have a substituent, or a -SO2-cyclic group that may have a substituent, L 201 Y represents -C(=O)- or -C(=O)-O-. 201 Each can be independently represented as arylene, alkylene, or alkenyl, where x is 1 or 2, and W 201 [This represents a linking group with a valence of (x+1).]

[0379] As R 201 ~R 207 and R 211 ~R 212 The aryl group in the aryl group can be exemplified by unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred.

[0380] As R 201~R 207 and R 211 ~R 212 The alkyl group in the alkyl group is preferably a chain-like or cyclic alkyl group with 1 to 30 carbon atoms.

[0381] As R 201 ~R 207 and R 211 ~R 212 The alkenyl group in the alkenyl group preferably has 2 to 10 carbon atoms.

[0382] As R 201 ~R 207 and R 210 ~R 212 The substituents that may be present include, for example, alkyl, halogen atom, haloalkyl, carbonyl, cyano, amino, aryl, and groups represented by the following formulas (ca-r-1) to (ca-r-7).

[0383] [Chemistry 31]

[0384]

[0385] [In the formula, R'] 201 Each group can be an independent hydrogen atom, a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents.

[0386] R' 201 Examples of substituent-containing cyclic groups, substituent-containing chain alkyl groups, or substituent-containing chain alkenyl groups can be related to R in formula (b-1). 101 The same group. Furthermore, as R' 201 The cyclic group may have substituents or the chain alkyl group may have substituents, and the same group as the acid-dissociable group in the above-described structural unit (a1)' may also be cited.

[0387] In R 201 ~R 203 R 206 ~R 207 R 211 ~R 212 When they bond together and form a ring with the sulfur atom in the formula, they can be linked via heteroatoms such as sulfur, oxygen, and nitrogen atoms, carbonyl groups, -SO-, -SO2-, -SO3-, -COO-, -CONH-, or -N(R) N )-(the R NThe ring is bonded to functional groups such as alkyl groups having 1 to 5 carbon atoms. The ring structure containing the sulfur atom in the formula is preferably a three- to ten-membered ring, particularly a five- to seven-membered ring. Specific examples of the formed ring include thiophene rings, thiazole rings, benzothiophene rings, dibenzothiophene rings, 9H-thioxanthium rings, thioxanone rings, thiathrone rings, phenoxathiin rings, tetrahydrothiophenonium rings, and tetrahydrothiaranonium rings.

[0388] R 208 ~R 209 Each of the above independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, in R 208 ~R 209 When they are alkyl groups, they can bond with each other to form a ring.

[0389] R 210 It can be an aryl group that may have a substituent, an alkyl group that may have a substituent, an alkenyl group that may have a substituent, or a -SO2- cyclic group that may have a substituent.

[0390] As R 210 The aryl group in the aryl group can be exemplified by unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred.

[0391] As R 210 The alkyl group in the alkyl group is preferably a chain or cyclic alkyl group with 1 to 30 carbon atoms.

[0392] As R 210 The alkenyl group in the form of the alkenyl group is preferably an alkenyl group with 2 to 10 carbon atoms.

[0393] As R 210 The group may contain a substituent-containing -SO2-cyclic group, preferably the "-SO2-containing polycyclic group", more preferably a group represented by the formula (a5-r-1)'.

[0394] Y 201 Each can be independently represented as arylene, alkylene, or alkenyl.

[0395] Y 201 The aryl group in the equation can be exemplified by R as described in equation (b-1). 101 The aromatic hydrocarbon group in the example is a group obtained by removing one hydrogen atom from the aryl group.

[0396] Y 201 The alkylene and alkenyl groups in the formula (b-1) can be exemplified by R. 101 The group obtained by removing one hydrogen atom from the chain alkyl or chain alkenyl groups exemplified in the text.

[0397] In the formula (ca-4), x is 1 or 2.

[0398] W 201 It is a (x+1) valence, that is, a divalent or trivalent linking group.

[0399] As W 201 The divalent linking group in the above formula (a1-1)' is preferably a divalent hydrocarbon group that may have substituents, and can be exemplified by Va in the above formula (a1-1)'. 1 Similarly, divalent hydrocarbon groups that can have substituents. W 201 The divalent linking group can be any of the following: linear, branched, or cyclic, preferably cyclic. Preferably, it is a group formed by combining two carbonyl groups at both ends of the arylene group. Examples of arylene groups include phenylene and naphthylene, with phenylene being particularly preferred.

[0400] As W 201 The trivalent linker group in W can be exemplified by the following: 201 Groups obtained by removing one hydrogen atom from a divalent linking group, and groups obtained by bonding another divalent linking group to the divalent linking group, etc. As W 201 The trivalent linking group in the group is preferably a group obtained by bonding two carbonyl groups to an arylene group.

[0401] As preferred cations represented by the formula (ca-1), examples can be given of cations represented by the formulas (ca-1-1) to (ca-1-67).

[0402] [Chemistry 32]

[0403]

[0404]

[0405] [In the formula, g1, g2, and g3 represent the number of repetitions, where g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 0 to 20.]

[0406] [Chemistry 33]

[0407]

[0408] [In the formula, R”] 201 A hydrogen atom or a substituent, as the substituent, and as said R 201 ~R 207 and R 210 ~R 212 The exemplified groups may be the same groups that can have substituents.

[0409] As preferred cations represented by the formula (ca-2), examples include diphenyliodonium cation, bis(4-tert-butylphenyl)iodonium cation, etc.

[0410] As preferred cations represented by the formula (ca-3), examples can be given of cations represented by the formulas (ca-3-1) to (ca-3-6) respectively.

[0411] [Chemistry 34]

[0412]

[0413] As preferred cations represented by the formula (ca-4), examples can be given of cations represented by the formulas (ca-4-1) to (ca-4-2) respectively.

[0414] [Chemistry 35]

[0415]

[0416] Of the above, the cation portion [(M' m+ ) 1 / m The preferred cation is represented by formula (ca-1), and more preferably by formulas (ca-1-1) to (ca-1-67).

[0417] As a preferred example of component (B), component (b-3) can be cited. In particular, as component (b-3), a combination of anionic portions represented by (d1-2-11) to (d1-2-31) as described later and cations represented by the formulas (ca-1-1) to (ca-1-16) can be used.

[0418] (B) Components may be used alone or in combination of two or more of the above-mentioned acid-producing agents.

[0419] The content of component (B) in the photoresist composition is preferably 0.1 to 50 parts by mass relative to 100 parts by mass of component (S) described later, and more preferably 0.1 to 40 parts by mass.

[0420] By setting the content of component (B) within the above-mentioned range, pattern formation is sufficiently achieved. Furthermore, when each component of the photoresist composition is dissolved in a solvent, a homogeneous solution is easily obtained, resulting in good storage safety for the photoresist composition, which is therefore preferred.

[0421] <Acid Diffusion Control Agent (D)>

[0422] The photoresist composition of the present invention contains an acid diffusion control agent (D) (hereinafter referred to as "(D) component"). The (D) component is a substance in the photoresist composition that functions as a quencher (acid diffusion control agent) for capturing acid generated by exposure.

[0423] The photoresist composition of the present invention may contain a photodegradable base (D1) (hereinafter referred to as "(D1) component") that loses its acid diffusion control through exposure decomposition, and may further contain a nitrogen-containing organic compound (D2) (hereinafter referred to as "(D2) component") that is not part of (D1) component.

[0424] Regarding component (D1)

[0425] By using a photoresist composition containing (D1) component, the contrast between the exposed and unexposed areas can be improved when forming a photoresist pattern.

[0426] As component (D1), there is no particular limitation on whether it is a component that loses acid diffusion control through exposure decomposition, but preferably one or more compounds selected from the group consisting of compounds represented by the following formula (d1-1) (hereinafter referred to as "(d1-1) component"), compounds represented by the following formula (d1-2) (hereinafter referred to as "(d1-2) component"), and compounds represented by the following formula (d1-3) (hereinafter referred to as "(d1-3) component").

[0427] The components (d1-1) to (d1-3) decompose in the exposed portion of the photoresist film and lose their acid diffusion control (alkalinity), thus they cannot function as quenchers, but they function as quenchers in the unexposed portion.

[0428] [Chemistry 36]

[0429]

[0430] [In the formula, Rd] 1 ~Rd 4 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents. Wherein, Rd in formula (d1-2) 2 The carbon atom adjacent to the S atom in Yd has an unbonded fluorine atom. 1 It is a single bond or a divalent linker. m is an integer greater than or equal to 1, and M m+ Each is an organic cation with an independent valence of m.

[0431] {(d1-1)Component}

[0432] Anion section

[0433] In equation (d1-1), Rd1 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents.

[0434] Among these, as Rd 1 Preferably, the substituent is an aromatic hydrocarbon group, an aliphatic cyclic group, or a chain alkyl group. Examples of substituents that may be present in these groups include hydroxyl, oxo, alkyl, aryl, fluorine, fluoroalkyl, lactone-containing cyclic groups represented by the formulas (a2-r-1)' to (a2-r-6)', ether bonds, ester bonds, or combinations thereof. When ether bonds or ester bonds are included as substituents, alkylene groups may be present.

[0435] The aromatic hydrocarbon group is more preferably phenyl or naphthyl.

[0436] The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from polycyclic alkanes such as adamantane, norbornene, isoboronane, tricyclodecane, and tetracyclododecane.

[0437] The preferred chain alkyl group has 1 to 10 carbon atoms. Specifically, examples include straight-chain alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; and branched-chain alkyl groups such as 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl.

[0438] The chain alkyl group may have fluorine atoms or fluoroalkyl groups as substituents, wherein the fluoroalkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8, and even more preferably 1 to 4. The fluoroalkyl group may contain atoms other than fluorine atoms. Examples of atoms other than fluorine atoms include oxygen atoms, sulfur atoms, and nitrogen atoms.

[0439] As Rd 1 Preferably, it is a fluoroalkyl group in which some or all of the hydrogen atoms constituting the straight-chain alkyl group are replaced by fluorine atoms, and particularly preferably it is a fluoroalkyl group (a straight-chain perfluoroalkyl group) in which all of the hydrogen atoms constituting the straight-chain alkyl group are replaced by fluorine atoms.

[0440] The following shows a preferred example of the anionic portion of component (d1-1).

[0441] [Chemistry 37]

[0442]

[0443] • Cation section

[0444] In equation (d1-1), M m+ It is an organic cation with an m valence.

[0445] As M m+ The organic cations may preferably be the same as the cations represented by the formulas (ca-1) to (ca-4), more preferably the cations represented by the formula (ca-1), and even more preferably the cations represented by the formulas (ca-1-1) to (ca-1-67).

[0446] (d1-1) Components can be used alone or in combination of two or more.

[0447] {(d1-2)Component}

[0448] Anion section

[0449] In equation (d1-2), Rd 2 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents.

[0450] Among them, Rd 2 The carbon atom adjacent to the S atom in the (d1-2) component has no bonded fluorine atom (no fluorine substitution). As a result, the anion of the (d1-2) component becomes a moderately weak acid anion, which enhances its quenching ability as a (D) component.

[0451] As Rd 2 Preferably, it is a chain alkyl group that may have substituents or an aliphatic cyclic group that may have substituents. As a chain alkyl group, it is preferably 1 to 10 carbon atoms, more preferably 3 to 10. As an aliphatic cyclic group, it is more preferably a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isoboronane, tricyclodecane, tetracyclododecane, etc. (which may have substituents); or a group obtained by removing one or more hydrogen atoms from camphor, etc.

[0452] Rd 2 The hydrocarbon group may have substituents, and examples of such substituents include Rd of formula (d1-1). 1 The hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) can have the same substituents as the group.

[0453] The following shows a preferred example of the anionic portion of component (d1-2).

[0454] [Chemistry 38]

[0455]

[0456] • Cation section

[0457] In equation (d1-2), Mm+ An organic cation with a valence of m is a cation related to M in formula (d1-1). m+ The same organic cation.

[0458] (d1-2) Components can be used alone or in combination of two or more.

[0459] {(d1-3)Component}

[0460] Anion section

[0461] In equation (d1-3), Rd 3 The alkyl group can be a cyclic group with substituents, a chain alkyl group with substituents, or a chain alkenyl group with substituents, preferably a cyclic group, a chain alkyl group, or a chain alkenyl group containing fluorine atoms. Fluorinated alkyl groups are preferred, and more preferably those related to the Rd group. 1 The same fluoroalkyl group as the fluoroalkyl group.

[0462] In equation (d1-3), Rd 4 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents.

[0463] Preferably, the alkyl, alkoxy, alkenyl, or cyclic groups may have substituents.

[0464] Rd 4 The alkyl group in the formula is preferably a straight-chain or branched alkyl group having 1 to 5 carbon atoms. Examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, etc. 4 A portion of the hydrogen atoms in an alkyl group can be replaced by hydroxyl, cyano, or other groups.

[0465] Rd 4 The alkoxy group is preferably an alkoxy group with 1 to 5 carbon atoms. Examples of alkoxy groups with 1 to 5 carbon atoms include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, and tert-butoxy. Among these, methoxy and ethoxy are preferred.

[0466] Rd 4 The alkenyl group is preferably vinyl, allyl, 1-methylpropenyl, or 2-methylpropenyl. These groups may further have alkyl groups having 1 to 5 carbon atoms or haloalkyl groups having 1 to 5 carbon atoms as substituents.

[0467] Rd 4 The cyclic group is preferably an alicyclic group obtained by removing one or more hydrogen atoms from cycloalkanes such as cyclopentane, cyclohexane, adamantane, norbornene, isoboronane, tricyclodecane, and tetracyclododecane, or an aromatic group such as phenyl or naphthyl. In Rd 4In the case of an alicyclic group, good photolithography properties are achieved by ensuring good dissolution of the photoresist composition in the solvent. Furthermore, in Rd... 4 When the photoresist composition is aromatic, it exhibits excellent light absorption efficiency and good sensitivity and photolithography properties in photolithography using EUV or similar light sources.

[0468] In equation (d1-3), Yd 1 It is a single bond or a divalent linker.

[0469] As Yd 1 The divalent linking group is not particularly limited. Examples include divalent hydrocarbon groups (aliphatic hydrocarbon groups, aromatic hydrocarbon groups) that can have substituents, and divalent linking groups containing heteroatoms.

[0470] As Yd 1 Preferably, it is a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. As an alkylene group, it is more preferably a straight-chain or branched alkylene group, and even more preferably a methylene or ethylene group.

[0471] The following shows a preferred example of the anionic portion of the (d1-3) component.

[0472] [Chemistry 39]

[0473]

[0474]

[0475] • Cation section

[0476] In equation (d1-3), M m+ An organic cation with a valence of m, and M in formula (d1-1) m+ same.

[0477] (d1-3) Components can be used alone or in combination of two or more.

[0478] Component (D1) can be any one of components (d1-1) to (d1-3) or a combination of two or more.

[0479] Of the above, as component (D1), it is preferable to use at least component (d1-1).

[0480] The content of component (D1) in the photoresist composition is preferably 0.1 to 5 parts by mass relative to 100 parts by mass of component (S), more preferably 0.1 to 4 parts by mass, and even more preferably 0.1 to 3 parts by mass.

[0481] If the content of component (D1) is above the preferred lower limit, it is easy to obtain particularly good photolithography properties and photoresist pattern shape. On the other hand, if it is below the upper limit, sensitivity can be well maintained.

[0482] (D1) Manufacturing method:

[0483] The manufacturing methods for components (d1-1) and (d1-2) are not particularly limited and can be manufactured using known methods.

[0484] Furthermore, the manufacturing method of components (d1-3) is not particularly limited, for example, it can be manufactured in the same way as the method described in US Patent Publication No. US2012-0149916.

[0485] Regarding component (D2)

[0486] As an acid diffusion control agent, it may further contain nitrogen-containing organic compound components that are not part of component (D1) (hereinafter referred to as "component (D2)").

[0487] As for component (D2), if it is a component that functions as an acid diffusion control agent and is not a component (D1), there are no particular limitations, and any known component may be used. Among them, aliphatic amines and aromatic amines are preferred.

[0488] Aliphatic amines are amines having one or more aliphatic groups, preferably with 1 to 12 carbon atoms.

[0489] Examples of aliphatic amines include amines (alkylamines or alkylolamines) or cyclic amines obtained by replacing at least one hydrogen atom of ammonia (NH3) with an alkyl or hydroxyalkyl group having 12 or fewer carbon atoms.

[0490] Specific examples of alkylamines and alkylolamines 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, di-n-octylamine, and dicyclohexylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkylolamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 5 to 10 carbon atoms are further preferred, and tri-n-pentylamine or tri-n-octylamine are particularly preferred.

[0491] As cyclic amines, for example, heterocyclic compounds containing a nitrogen atom as a heteroatom can be cited. Such heterocyclic compounds can be monocyclic (aliphatic monocyclic amines) or polycyclic (aliphatic polycyclic amines).

[0492] As aliphatic monocyclic amines, examples include piperidine and piperazine.

[0493] As an aliphatic polycyclic amine, it is preferred to have 6 to 10 carbon atoms. Specifically, examples include 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.

[0494] Other aliphatic amines include tris(2-methoxymethoxyethyl)amine, tri{2-(2-methoxyethoxy)ethyl}amine, tri{2-(2-methoxyethoxymethoxy)ethyl}amine, tri{2-(1-methoxyethoxy)ethyl}amine, tri{2-(1-ethoxyethoxy)ethyl}amine, tri{2-(1-ethoxypropoxy)ethyl}amine, tri[2-{2-(2-hydroxyethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, etc., with triethanolamine triacetate being preferred.

[0495] In addition, aromatic amines can be used as (D2) components.

[0496] Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or their derivatives, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, 2,4-diamino-6-phenyl-1,3,5-triazine, etc., with N-tert-butoxycarbonylpyrrolidine and 2,4-diamino-6-phenyl-1,3,5-triazine being preferred, and 2,4-diamino-6-phenyl-1,3,5-triazine being more preferred.

[0497] (D2) Components can be used alone or in combination of two or more.

[0498] When the photoresist composition contains component (D2), component (D2) can be used in the range of 0.005 to 3 parts by mass relative to 100 parts by mass of component (S). By setting it to the range described above, the pattern shape of the photoresist, the stability over time after exposure, etc., are improved.

[0499] Additive (E)

[0500] In order to improve the properties of the photoresist composition, the photoresist composition of the present invention may contain at least one additive (E) (hereinafter referred to as "(E) component"). The (E) component is a component that is different from the components (A) and (B) described above, and is also different from the components described in the component (S) described later.

[0501] The photoresist composition of the present invention can contain any suitable crosslinking agent (E1) (hereinafter referred to as "(E1) component") capable of crosslinking resin component (A) in the presence of an acid. Non-limiting examples of the (E1) component include resins containing melamine, hydroxymethyl, glycoluril, polymeric glycoluril, benzoguanidine, urea, hydroxyalkylamides, epoxy and epoxyamine resins, block isocyanates, and divinyl monomers. Monomers such as hexamethoxymethylmelamine, glycoluril derivatives, or aromatic hydroxymethyl groups such as 2,6-bis(hydroxymethyl)-p-cresol can be used.

[0502] The (E1) component used in this invention is preferably a glycourea derivative, and more preferably tetra(methoxymethyl)glycourea, tetra(butoxymethyl)glycourea, etc.

[0503] The (E1) component can be used alone or in combination with two or more components. When the photoresist composition contains the (E1) component, the content of the (E1) component relative to 100 parts by mass of the (A) component is preferably 1 to 50 parts by mass, more preferably 3 to 30 parts by mass, and even more preferably 5 to 20 parts by mass.

[0504] In order to achieve excellent adhesion, the photoresist composition of the present invention may contain a compound (E2) having one or more polar groups. When the photoresist composition contains a compound having one or more polar groups, the amount of solvent remaining in the photoresist layer is reduced when forming the photoresist pattern, and the adhesion between the support and the photoresist pattern is improved.

[0505] The polar groups of the compound having one or more polar groups are preferably selected from the group consisting of hydroxyl, amino, mercapto, carboxyl and sulfonic acid groups, more preferably from the group consisting of hydroxyl, amino and carboxyl groups, and most preferably hydroxyl.

[0506] From the perspective of improving the adhesion with the support, the compound having one or more polar groups is preferably a compound with a molecular weight of 2,000 or less, more preferably a compound with a molecular weight of 1,500 or less, and even more preferably a compound with a molecular weight of 1,000 or less.

[0507] Furthermore, from the perspective of improving the adhesion to the support, the compound having one or more polar groups is preferably a compound having one or more hydroxyl groups, and in this case, the compound having one or more hydroxyl groups is preferably a compound represented by formula (e-1).

[0508] [Chemistry 40]

[0509] A(OH) p (e-1)

[0510] [In the formula, A is a straight-chain hydrocarbon group with 1 to 10 carbon atoms or a branched hydrocarbon group with 3 to 10 carbon atoms, and p is an integer from 1 to 3.]

[0511] In A of the formula (e-1), the number of carbon atoms in the straight-chain hydrocarbon group is preferably 2 to 8, and more preferably 4 to 6.

[0512] In A of the formula (e-1), the branched hydrocarbon group preferably has 4 to 8 carbons, more preferably 5 to 6.

[0513] In the formula (e-1), p is preferably 2 to 3, and more preferably 3.

[0514] Furthermore, when the compound having one or more polar groups is a compound having one or more amino groups, the compound having one or more amino groups is preferably a compound represented by formula (e-2).

[0515] [Chemistry 41]

[0516] B(NH2) q (e-2)

[0517] [In the formula, B is a straight-chain hydrocarbon group with 1 to 10 carbon atoms or a branched hydrocarbon group with 3 to 10 carbon atoms, and q is an integer from 1 to 3.]

[0518] In formula (e-2), B has 2 to 8 carbon atoms in the straight-chain hydrocarbon group, more preferably 4 to 6.

[0519] In formula (e-2), the branched hydrocarbon group preferably has 4 to 8 carbon atoms, more preferably 5 to 6.

[0520] In the formula (e-2), q is preferably 2 to 3, and more preferably 3.

[0521] Furthermore, when the compound having one or more polar groups is a compound having one or more carboxyl groups, the compound having one or more carboxyl groups is preferably a compound represented by formula (e-3).

[0522] [Chemistry 42]

[0523] D(COOH) r (e-3)

[0524] [In the formula, D represents a straight-chain hydrocarbon group with 1 to 10 carbon atoms or a branched hydrocarbon group with 3 to 10 carbon atoms, and r is an integer from 1 to 3.]

[0525] In the D of formula (e-3), the number of carbon atoms in the straight-chain hydrocarbon group is preferably 2 to 8, and more preferably 4 to 6.

[0526] In the D of formula (e-3), the branched hydrocarbon group preferably has 4 to 8 carbons, more preferably 5 to 6.

[0527] In the formula (e-3), r is preferably 2 to 3, and more preferably 3.

[0528] (E2) Components can be used alone or in combination with two or more.

[0529] When the photoresist composition contains (E2), the content of (E2) is preferably 1 to 50 parts by mass relative to 100 parts by mass of (S), more preferably 3 to 30 parts by mass, and even more preferably 5 to 20 parts by mass. By setting it within the above range, the adhesion of the thick-film photoresist layer to the support is improved.

[0530] Solvent (S)

[0531] The photoresist composition of the present invention can be manufactured by dissolving the photoresist material in a solvent (S) (hereinafter referred to as "(S) component").

[0532] As component (S), any component that can dissolve the various components used to form a homogeneous solution is acceptable, and there are no particular limitations. Therefore, any component can be appropriately selected from substances known conventionally as solvents for photoresist compositions, and can be selected from the range of conditions of the present invention that satisfy the requirement that an appropriate amount of residual solvent remains on the photoresist film before pattern formation.

[0533] Examples include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,2-hexanol, and 1,3-butanediol; compounds containing ester bonds such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate; and monoalkyl ethers or monophenyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, and monobutyl ether of the polyols or the compounds containing ester bonds. Derivatives of polyols such as compounds with ether bonds; cyclic ethers such as dioxane; esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic solvents such as anisole, ethyl benzyl ether, methyl toluene, diphenyl ether, dibenzyl ether, phenethyl ether, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylene, cumene, toluene, xylene, isopropyl toluene, and mesitylene; dimethyl sulfoxide (DMSO); propylene carbonate, etc.

[0534] The compound having an ester bond can be a monoacetate or a diacetate represented by the following general formula (s-1).

[0535] [Chemistry 43]

[0536] R s -(O-CO-CH3) n1 (s-1)

[0537] In the formula, n1 is 1 or 2, R s It is an alkyl group having 5 to 10 carbon atoms that may have substituents, wherein the number of carbon atoms includes the number of carbon atoms of the substituents.

[0538] The R s The alkyl group having 5 to 10 carbon atoms may have a substituent, which may be a substituted R. s A substituent of some or all of the hydrogen atoms in the alkyl group, or a substituent of R. s Substituents on the carbon atoms of the alkyl backbone.

[0539] As a replacement for R s Substituents for some or all of the hydrogen atoms of the alkyl group may include, for example, lower alkyl groups having 1 to 5 carbon atoms, lower alkoxy groups having 1 to 5 carbon atoms, fluorine atoms, fluorinated lower alkyl groups having 1 to 5 carbon atoms obtained by substitution with fluorine atoms, oxygen atoms (=O), etc. Among these, lower alkoxy groups having 1 to 5 carbon atoms are preferred, and methoxy groups (-OCH3) are more preferred.

[0540] As a replacement for R s Substituents on the carbon atoms of the alkyl backbone are preferably divalent linking groups containing heteroatoms. Examples of such divalent linking groups containing heteroatoms include -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, and "-AO(oxygen atom)-B- (where A and B are each independently divalent hydrocarbon groups that may have substituents)". Examples of substituents that A and B may have include those that replace the R group. s Substituents that are one or all of the hydrogen atoms of an alkyl group, and the same substituents as those listed.

[0541] Examples of monoacetic or diacetic esters represented by the general formula (s-1) include 3-methoxybutylacetic acid ester (abbreviation = MBA; boiling point = 171°C; SP value = 871), dipropylene glycol methyl ether acetate ester (abbreviation = DPMA; boiling point = 213°C; SP value = 871), propylene glycol diacetic acid ester (abbreviation = PGDA; boiling point = 190°C; SP value = 960), and 1,3-butanediol diacetic acid ester (abbreviation = 1,3BGDA; boiling point = 171°C; SP value = 871), etc. 232℃; SP value = 1011), cyclohexanol acetate (abbreviation = CHXA; boiling point = 173℃; SP value = 918), ethylene glycol monobutyl ether acetate (abbreviation = BMGAC; boiling point = 188℃; SP value = 885), diethylene glycol monoethyl ether acetate (abbreviation = EGAC; boiling point = 217℃; SP value = 901), diethylene glycol monobutyl ether acetate (abbreviation = BGAC; boiling point = 247℃; SP value = 894), etc.

[0542] As the (S) component, preferred components include DPMA, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), 2-heptanone, 1,2-hexanediol, and 1,3-butanediol.

[0543] Component (S) can be used alone or as a mixed solvent of two or more components. The amount of component (S) used is not particularly limited and can be appropriately set according to the coating film thickness at a concentration suitable for coating onto a substrate, etc. Component (S) can be used in a range of 30 to 70% by mass of the solid component concentration in the photoresist composition, and more preferably in a range of 5 to 20% by mass.

[0544] <Compound(X)>

[0545] In order to improve the properties of the photoresist composition, the photoresist composition of the present invention contains at least one compound (X) represented by the following formula (x-1).

[0546] [Chemistry 44]

[0547]

[0548] [In the formula, R] 1 ~R 4 Each is independently a hydroxyl group or an alkyl group having 1 to 5 carbon atoms, R 5 and R 6 Each of the following is independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 10 carbon atoms obtained by substitution with a hydroxyl group; a, b, c, and d are independently integers from 0 to 3; e and f are independently integers from 1 to 2.

[0549] The alkyl group having 1 to 5 carbon atoms is preferably a straight-chain or branched alkyl group having 1 to 5 carbon atoms, and more preferably a straight-chain alkyl group. Specifically, examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, etc.

[0550] The alkyl group having 1 to 10 carbon atoms obtained by substituted with hydroxyl groups is preferably a straight-chain or branched alkyl group having 1 to 10 carbon atoms obtained by substituted with one or more hydroxyl groups, and is more preferably a straight-chain alkyl group.

[0551] The R 1 and R 2 R 3 and R 4 R 5 and R 6 The groups can be the same as each other or different, but are preferably the same. The numbers of a and b, c and d, e and f can be the same as each other or different, but are preferably the same.

[0552] As compound (X), the compound represented by the following formula is preferred.

[0553] [Chemistry 45]

[0554]

[0555] [In the formula, R] 5 and R 6 Same as the definition in equation (x-1).

[0556] As compound (X), compounds represented by the following formula are also preferred.

[0557] [Chemistry 46]

[0558]

[0559] [In the formula, R] 3 and R 4 Same as the definition in equation (x-1).

[0560] Specific examples of compound (X) are given below.

[0561] [Chemistry 47]

[0562]

[0563] By using the compound (X), an effect of improved sensitivity can be achieved, and the shape can be maintained while maintaining high resolution.

[0564] Component (X) can be used alone or as a mixture of two or more components. The content of component (X) in the photoresist composition is preferably 1 to 25 parts by mass relative to 100 parts by mass of component (A), more preferably 1 to 20 parts by mass, and even more preferably 2 to 15 parts by mass.

[0565] Example

[0566] The present invention will be further described in detail below by way of examples, but the present invention is not limited to these examples.

[0567] <Preparation of Photoresist Compositions>

[0568] The photoresist compositions of each example were prepared by mixing and dissolving the components shown in Tables 1 and 2 below.

[0569] Table 1

[0570]

[0571] Table 2

[0572]

[0573] In Tables 1 and 2, each abbreviation has the following meaning, and the value in [] is the amount of blending (parts by mass).

[0574] (A)Ingredients

[0575] Polymer compound (A)-1 containing the following structural units in an x:y ratio:

[0576] [Chemistry 48]

[0577] (x:y = 85:15)

[0578] (B) Ingredients

[0579] Acid-producing agents represented by the following chemical formulas.

[0580] [Chemistry 49]

[0581]

[0582] (D) Components

[0583] An acid diffusion control agent represented by the following chemical formula.

[0584] [Transformation 50]

[0585]

[0586] [Chemistry 51]

[0587]

[0588] [Chemistry 52]

[0589]

[0590] [Chemistry 53]

[0591]

[0592] (D2)-1: Triethylamine (E1) component

[0593] [Chemistry 54]

[0594]

[0595] Tetra(methoxymethyl)glycourea (S) component (S)-1: dipropylene glycol methyl ether acetate (DPMA) (S)-2: 1,2-hexanediol

[0596] (S)-3: 2-Hepenoestan

[0597] (S)-4: 1,3-Butanediol; (S)-5: Dipropylene glycol methyl ether; (S)-6: γ-Butyrolactone (GBL)

[0598] (S)-7: Propylene carbonate; (S)-8: Propylene glycol monomethyl ether acetate (PGMEA)

[0599] (S)-9: Propylene glycol monomethyl ether (PGME)

[0600] (X) component

[0601] [Chemistry 55]

[0602]

[0603] 2,2'-Dimethyl-4,4'-(fluorene-9,9-diyl)diol

[0604] [Chemistry 56]

[0605]

[0606] 4,4'-(9-fluoreneyl)diol

[0607] [Chemistry 57]

[0608]

[0609] Diphenoxyethanolfluorene

[0610] [Chem.58]

[0611]

[0612] 4,4'-Cyclohexylbisphenol

[0613] <Measurement of Residual Solvent in Membrane>

[0614] The compositions described in Tables 1 and 2 were coated onto 8-inch silicon wafers and baked at 100°C for 60 seconds to achieve a film thickness of 300 nm. The photoresist film on the silicon wafer was cut out, and the amount of residual solvent was measured using a GC-flame ionization detector. The values ​​are shown in Table 3 below.

[0615] Table 3

[0616] Film residual solvent amount (ppm) Example 1 1040 Example 2 1040 Example 3 1040 Example 4 1040 Example 5 1040 Example 6 1040 Example 7 980 Example 8 960 Example 9 910 Comparative Example 1 1040 Comparative Example 2 900 Comparative Example 3 1040 Comparative Example 4 850 Comparative Example 5 720 Comparative Example 6 810 Comparative Example 7 890

[0617] Formation of photoresist patterns

[0618] On a 12-inch silicon wafer, the compositions of Tables 1 and 2 are coated using a coating machine, and then pre-baked (PAB) at 100°C for 60 seconds on a hot plate to dry, thereby forming a photoresist film with a thickness of 300 μm.

[0619] Next, the photoresist film was selectively irradiated with a KrF excimer laser (248 nm) through a mask pattern (binary mask) using a KrF exposure apparatus NSR-S210D (Nikon Corporation; NA (numerical aperture) = 0.82, σ = 0.90).

[0620] Then, it undergoes a post-exposure heating (PEB) treatment at 110°C for 90 seconds.

[0621] Next, alkaline development was performed using a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution “NMD-3” (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) as the developer at 23°C for 60 seconds. Then, the mixture was rinsed with pure water for 30 seconds and dried.

[0622] <Characteristic Evaluation of Photoresist Patterns>

[0623] The properties of the photoresist pattern formed as described above are evaluated as follows.

[0624] (Standing wave ratio)

[0625] Standing wave (SW) is a value obtained by quantifying the cross-sectional shape of the formed photoresist pattern. It is expressed as the width of the thinnest part of the cross-section (MIN) / the width of the thickest part of the cross-section (MAX), and the closer it is to 1.0, the better.

[0626] (Depth of Focus (DOF))

[0627] In order to form fine patterns, a large depth of focus is required.

[0628] The photoresist patterns formed by the photoresist compositions of Examples 1-9 and Comparative Examples 1-7 were observed using a scanning electron microscope (SEM), and the SW value and DOF were determined.

[0629] They are shown in Table 4 below.

[0630] Table 4

[0631] SW value DOF Example 1 0.85 450 Example 2 0.74 550 Example 3 0.82 550 Example 4 0.84 550 Example 5 0.89 550 Example 6 0.73 450 Example 7 0.75 500 Example 8 0.59 350 Example 9 0.55 400 Comparative Example 1 0.90 150 Comparative Example 2 0.41 250 Comparative Example 3 0.42 250 Comparative Example 4 0.43 250 Comparative Example 5 0.32 200 Comparative Example 6 0.36 200 Comparative Example 7 0.39 250

[0632] The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications to the configuration may be made without departing from the spirit of the present invention.

Claims

1. A method for forming a photoresist pattern, comprising: (i) The process of forming a photoresist film on a support using a photoresist composition; (ii) The process of exposing the photoresist film; and (iii) The step of developing the exposed photoresist film to form a photoresist pattern, characterized in that, The photoresist composition comprises: a resin (A) that undergoes cross-linking under the action of acid and changes its solubility in the developer; an acid-generating agent (B) that generates acid upon exposure; a photodegradable alkali (D1); a cross-linking agent (E1); a solvent (S); and a compound (X) represented by the following formula (x-1). In the formula, R 1 ~R 4 Each is independently a hydroxyl group or an alkyl group having 1 to 5 carbon atoms, R 5 and R 6 Each of the following is independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 10 carbon atoms obtained by substitution with a hydroxyl group; a, b, c, and d are independently integers from 0 to 3; e and f are independently integers from 1 to 2. The resin (A) comprises a structural unit (a10) represented by the following formula (a10-1). In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a haloalkyl group having 1 to 5 carbon atoms, and Ya x1 Wa is a single bond or a divalent linker. x1 For (n ax1 +1) valence aromatic hydrocarbon group, n ax1 Integers from 1 to 3 The proportion of the structural unit (a10) in the resin (A) is 55-95 mol% relative to the total 100 mol% of all structural units constituting the resin (A). The photodegradable base (D1) is one or more compounds selected from the group consisting of compounds represented by the following formulas (d1-1), (d1-2) and (d1-3). In the formula, Rd 1 ~Rd 4 It can be a cyclic group that may have substituents, a chain alkyl group that may have substituents, or a chain alkenyl group that may have substituents, wherein Rd in formula (d1-2) 2 In the middle, the carbon atom adjacent to the S atom has an unbonded fluorine atom, Yd 1 It is a single bond or a divalent linker, where m is an integer greater than or equal to 1, and M m+ Each is independently selected from the group consisting of cations represented by the following formulas (ca-1) to (ca-4). In the formula, R 201 ~R 207 and R 211 ~R 212 Each can independently represent an aryl, alkyl, or alkenyl group that may have substituents, R 201 ~R 203 R 206 ~R 207 R 211 ~R 212 They can bond with each other and form a ring together with the sulfur atoms in the formula, R 208 ~R 209 Each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R 210 It can be an aryl group that may have a substituent, an alkyl group that may have a substituent, an alkenyl group that may have a substituent, or a -SO2-cyclic group that may have a substituent, L 201 Y represents -C(=O)- or -C(=O)-O-. 201 Each can be independently represented as arylene, alkylene, or alkenyl, where x is 1 or 2, and W 201 The linking group represents the (x+1) valence. The crosslinking agent (E1) is at least one selected from the group consisting of melamine, hydroxymethyl, glycourea, polymeric glycourea, glycourea derivatives, benzoguanamine, urea, hydroxyalkylamide resins, epoxy and epoxyamine resins, block isocyanates, and divinyl monomers. The amount of residual solvent in the photoresist film formed in step (i) is 910 ppm or more.

2. The method for forming a photoresist pattern as described in claim 1, characterized in that, In the formula, a, b, c, and d are 0, e and f are 1, and R 5 and R 6 Each can be independently hydrogen or -(CH2). n -OH, where n is an integer from 1 to 5.

3. The method for forming a photoresist pattern as described in claim 1 or 2, characterized in that, The crosslinking agent (E1) is a glycourea derivative.

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