JP2021092779A - Photoresist pattern forming method - Google Patents

Abstract

To provide a photoresist pattern forming method capable of forming a pattern having a good shape while maintaining high resolution.SOLUTION: The photoresist pattern forming method includes the steps of: (i) forming a photoresist film on a support using a photoresist composition; (ii) exposing the photoresist film; and (iii) developing the photoresist film after the exposure to form a photoresist pattern. The photoresist composition contains a resin (A), an acid generator (B), a photodegradable base (D1), a solvent (S), and a compound (X) represented by the following formula (x-1). The amount of solvent remaining in the photoresist film formed in the step (i) is 910 ppm or more.SELECTED DRAWING: None

Description

The present invention relates to a method for forming a photoresist pattern.

In the lithography technology, for example, a photoresist film composed of a resist material is formed on a substrate, the photoresist film is selectively exposed, and a development process is performed to determine the photoresist film. A step of forming a photoresist pattern of the shape is performed. A resist material whose exposed portion of the photoresist film changes to a characteristic of being soluble in a developing solution is called a positive type, and a resist material whose exposed portion of a photoresist film changes to a characteristic of not being dissolved in a developing solution is called a negative type.

In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has progressed due to advances in lithography technology. As a miniaturization method, generally, the wavelength of the exposure light source is shortened (energy is increased). Specifically, in the past, ultraviolet rays typified by g-rays and i-rays were used, but nowadays, mass production of semiconductor elements using KrF excimer lasers and ArF excimer lasers is being carried out. ing. In addition, EUV (extreme ultraviolet), EB (electron beam), X-ray, etc., which have a shorter wavelength (high energy) than these excimer lasers, are also being studied.

With the further progress of lithography technology and the expansion of application fields, various improvements in lithography characteristics such as higher sensitivity, resolution, and roughness are required in the formation of photoresist patterns. ..
As a photoresist composition for forming a photoresist film, generally, a photoresist composition containing a resin component whose solubility in a developing solution is changed by the action of an acid and an acid generator component that generates an acid by exposure is used. Has been done. The photoresist composition may contain a nitrogen-containing compound as an acid diffusion control agent component that traps the acid generated by exposure, but the acid is decomposed by exposure as compared with the conventional amine type acid diffusion control agent. The resolution is improved by using the acid diffusion control system in the form of a photodisintegrant base that loses diffusion controllability, but the solution is high when a photodisintegrant base is used as an acid diffusion control agent in a KrF negative photoresist. There is a problem that it is difficult to maintain the shape while maintaining the image quality.

On the other hand, it has been pointed out that the line edge roughness of the film increases and the pattern film decreases as the resist becomes finer and thinner, and it is pointed out that leaving an appropriate amount of solvent in the film causes in-edge roughness. It is known that it is necessary for the reduction of the amount (see Patent Document 1). However, an effective method for controlling the amount of residual solvent in the membrane and the relationship between the amount of residual solvent in the membrane and other properties of the resist are not yet fully known.

Japanese Patent No. 4857208

The present invention has been made in consideration of the above circumstances, and provides a photoresist pattern forming method capable of forming a pattern having a good shape while maintaining high resolution.

The configuration adopted by the present invention in order to achieve the above object is as follows.
Through examination, the present inventors have found that the above problems can be solved through the following photoresist pattern forming method, and have completed the present invention.
(I) A step of forming a photoresist film on a support using a photoresist composition;
(Ii) A photoresist pattern forming method comprising a step of exposing the photoresist film; and (iii) a step of developing the exposed photoresist film to form a photoresist pattern.
The photoresist composition comprises a resin (A) whose solubility in a developing solution changes due to the action of an acid, an acid generator (B) that generates an acid upon exposure, a photodegradable base (D1), a solvent (S) and Contains the compound (X) represented by the following formula (x-1),
A method for forming a photoresist pattern, wherein the amount of the solvent remaining on the photoresist film formed in the step (i) is 910 ppm or more.

[式中、Ｒ^１〜Ｒ^４は、それぞれ独立に、ヒドロキシ基又は炭素数１〜５のアルキル基であり、Ｒ^５及びＲ^６は、それぞれ独立に、水素、炭素数１〜５のアルキル基又はヒドロキシ基で置換された炭素数１〜１０のアルキル基であり、ａ、ｂ、ｃ及びｄは、それぞれ独立に、０〜３の整数であり、ｅ及びｆは、それぞれ独立に、１〜２の整数である。]

[In the formula, R ^{1 to} R ⁴ are independently hydroxy groups or alkyl groups having 1 to 5 carbon atoms, and R ⁵ and R ⁶ are independently hydrogen and alkyl groups having 1 to 5 carbon atoms, respectively. Alternatively, it is an alkyl group having 1 to 10 carbon atoms substituted with a hydroxy group, a, b, c and d are independently integers of 0 to 3, and e and f are independently 1 to 1, respectively. It is an integer of 2. ]

The photoresist pattern obtained by the photoresist pattern forming method of the present invention can form a pattern having a good shape while maintaining high resolution.

In the description of the present invention and the scope of the present invention, "aliphatic" is defined as a concept relative to aromatics and means a group, a compound or the like having no aromaticity.
Unless otherwise specified, the "alkyl group" shall include linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
Unless otherwise specified, the "alkylene group" shall include linear, branched and cyclic divalent saturated hydrocarbon groups.
The "alkyl halide group" is a group in which a part or all of the hydrogen atom of the alkyl group is substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
The "fluorinated alkyl group" or "fluorinated alkylene group" refers to a group in which a part or all of hydrogen atoms of the alkyl group or the alkylene group is substituted with a fluorine atom.
The "constituent unit" means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).
The “constituent unit derived from the acrylic acid ester” means a structural unit formed by cleaving the ethylenic double bond of the acrylic acid ester.
The "acrylic acid ester" is a compound in which the hydrogen atom at the terminal of the carboxy group of _{acrylic acid (CH 2 = CH-COOH) is replaced with an organic group.}
In the acrylic acid ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. ^{The substituent (R α0} ) that replaces the hydrogen atom bonded to the carbon atom at the α-position is an atom or group other than the hydrogen atom, for example, an alkyl group having 1 to 5 carbon atoms and a halogenation having 1 to 5 carbon atoms. Examples include an alkyl group. Further, the carbon atom at the α-position of the acrylic acid ester is a carbon atom to which the carbonyl group of acrylic acid is bonded unless otherwise specified.
Hereinafter, an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylic acid ester. Further, the acrylic acid ester and the α-substituted acrylic acid ester may be collectively referred to as “(α-substituted) acrylic acid ester”.
"Constituent unit derived from hydroxystyrene or hydroxystyrene derivative" means a structural unit formed by cleaving the ethylenic double bond of hydroxystyrene or hydroxystyrene derivative.
The "hydroxystyrene derivative" is a concept including a hydrogen atom at the α-position of hydroxystyrene substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. As those derivatives, the hydrogen atom at the α-position may be substituted with a substituent, and the hydrogen atom of the hydroxy group of hydroxystyrene is substituted with an organic group; the hydrogen atom at the α-position is substituted with a substituent. Examples thereof include those in which a substituent other than the hydroxy group is bonded to the benzene ring of hydroxystyrene. The α-position (carbon atom at the α-position) of hydroxystyrene means a carbon atom to which a benzene ring is bonded, unless otherwise specified.
Examples of the substituent substituting the hydrogen atom at the α-position of hydroxystyrene include those similar to those mentioned as the substituent at the α-position in the α-substituted acrylic acid ester.
The "constituent unit derived from vinyl benzoic acid or a vinyl benzoic acid derivative" means a structural unit formed by cleaving the ethylenic double bond of vinyl benzoic acid or a vinyl benzoic acid derivative.
The "vinyl benzoic acid derivative" is a concept including those in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. As those derivatives, the hydrogen atom at the α-position may be substituted with a substituent, and the hydrogen atom of the carboxy group of vinyl benzoic acid is substituted with an organic group; the hydrogen atom at the α-position is substituted with a substituent. Examples thereof include those in which a substituent other than the hydroxy group and the carboxy group is bonded to the benzene ring of vinyl benzoic acid. The α-position (alpha-position carbon atom) of vinylbenzoic acid means a carbon atom to which a benzene ring is bonded, unless otherwise specified.
The "styrene derivative" is one in which the hydrogen atom at the α-position of styrene is substituted with another substituent such as an alkyl group or an alkyl halide group, and the hydrogen atom of the phenyl group of styrene has 1 to 5 carbon atoms. It means one substituted with a substituent such as a lower alkyl group.
“Constituent unit derived from styrene” and “constituent unit derived from a styrene derivative” mean a structural unit formed by cleaving an ethylenic double bond of styrene or a styrene derivative.
The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, and specifically, an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group). , N-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.
Further, as the alkyl halide group as the substituent at the α-position, specifically, a group in which a part or all of the hydrogen atom of the “alkyl group as the substituent at the α-position” is substituted with a halogen atom can be mentioned. .. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable.
Specific examples of the hydroxyalkyl group as the substituent at the α-position include a group in which a part or all of the hydrogen atom of the “alkyl group as the substituent at the α-position” is substituted with a hydroxy group. The number of hydroxy groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.
When describing "may have a substituent", when the hydrogen atom (-H) is replaced with a monovalent group and when the methylene group (-CH _2- ) is replaced with a divalent group. Including both.
"Exposure" is a concept that includes general irradiation of radiation.

<< Photoresist pattern formation method >>
The photoresist pattern forming method of the present invention
(I) A step of forming a photoresist film on a support using a photoresist composition;
(Ii) includes a step of exposing the photoresist film; and (iii) a step of developing the exposed photoresist film to form a photoresist pattern.

In such a photoresist pattern forming method, in step (i), a specific photoresist composition according to the present invention is selected and used.
Step (i): First, a specific photoresist composition described later is applied onto the support with a spinner or the like, and a baking (post-apply baking (PAB)) treatment is performed, for example, at 80 to 150 ° C., preferably 80 to. A photoresist film is formed at a temperature condition of 120 ° C. (more preferably 100 ° C.) for 40 to 120 seconds, preferably 50 to 100 seconds (more preferably 60 seconds).
Step (ii): The photoresist film is selectively exposed by, for example, using an exposure apparatus or the like through a mask (mask pattern) on which a predetermined pattern is formed, and then baked (posted). The exposure baking (PEB) treatment is performed, for example, under temperature conditions of 80 to 150 ° C., preferably 90 to 130 ° C. for 40 to 120 seconds, more preferably 60 to 100 seconds.
Step (iii): Next, the photoresist film after the exposure is developed. In the case of the alkaline developing process, the developing process is performed using an alkaline developing solution, and in the case of the solvent developing process, a developing solution containing an organic solvent (organic developing solution) is used. After the development treatment, a rinsing treatment is preferably performed. In the case of the alkaline development process, the rinsing treatment is preferably a water rinse using pure water, and in the case of the solvent development process, it is preferable to use a rinse liquid containing an organic solvent. In the case of the solvent development process, after the development treatment or the rinsing treatment, a treatment for removing the developing solution or the rinsing solution adhering to the pattern with a supercritical fluid may be performed.
Drying is performed after the development treatment or the rinsing treatment. In some cases, a baking process (post-baking) may be performed after the development process.
In this way, the photoresist pattern can be formed.

The support is not particularly limited, and conventionally known ones can be used. Examples thereof include a substrate for electronic components and a support having a predetermined wiring pattern formed therein. More specifically, silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, glass substrates, and the like can be mentioned. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold and the like can be used.
Further, the support may be one in which an inorganic film and / or an organic film is provided on the substrate as described above. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). Examples of the organic film include an organic antireflection film (organic BARC) and an organic film such as a lower organic film in the multilayer resist method. Here, the multilayer resist method is a resist formed on an upper resist film by providing at least one additional organic film (lower layer organic film) and at least one additional resist film (upper layer resist film) on the substrate. This is a method of patterning the lower organic film using the pattern as a mask, and can form a pattern having a high aspect ratio. That is, according to the multilayer resist method, since the required thickness can be secured by the lower organic film, the resist film can be thinned and a fine pattern having a high aspect ratio can be formed. The multilayer resist method basically includes a method of forming a two-layer structure of an upper resist film and a lower organic film (two-layer resist method), and one or more intermediate layers between the upper resist film and the lower organic film. It can be divided into a method of forming a multilayer structure of three or more layers provided with (metal thin film, etc.) (three-layer resist method).

The wavelength used for exposure is not particularly limited, and radiation such as ArF excimer laser, KrF excimer laser, F2 excimer laser, EUV (extreme ultraviolet rays), VUV (vacuum ultraviolet rays), EB (electron beam), X-rays, and soft X-rays. Can be done using. The resist pattern forming method according to the present invention is particularly suitable when the resist film is irradiated with KrF excimer laser light in the step (ii).

The exposure method of the resist film may be a normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or an immersion exposure (Liquid Imaging Lithography).
In immersion exposure, the space between the resist film and the lens at the lowest position of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than the refractive index of air, and exposure (immersion exposure) is performed in that state. This is an exposure method. As the immersion medium, a solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film to be exposed is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range. Examples of the solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent. Specific examples of the fluorine-based inert liquid include fluorine-based compounds such _{as C 3} HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F _{7 as main components.} Examples thereof include liquids, those having a boiling point of 70 to 180 ° C., and more preferably those having a boiling point of 80 to 160 ° C. It is preferable that the fluorine-based inert liquid has a boiling point in the above range because the medium used for immersion can be removed by a simple method after the end of exposure. As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound. Further, examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point 102 ° C.), and examples of the perfluoroalkylamine compound include perfluorotributylamine (boiling point 174 ° C.). Can be mentioned. As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility and the like.

Examples of the alkaline developer used in the developing process in the alkaline developing process include an aqueous solution of 0.1 to 10 mass% tetramethylammonium hydroxide (TMAH).
The organic solvent contained in the organic developer used in the developing process in the solvent developing process may be any known organic solvent as long as it can dissolve the component (A) described later (component (A) before exposure). You can select from the appropriate ones. The solvent will be described in detail in the description of the resist composition below.

The developing process can be carried out by a known developing method. For example, a method of immersing the support in a developing solution for a certain period of time (dip method), or a method of raising the developing solution on the surface of the support by surface tension for a certain period of time. The method of standing still (paddle method), the method of spraying the developer on the surface of the support (spray method), the method of applying the developer on the support rotating at a constant speed while scanning the developer dispensing nozzle at a constant speed. Examples include a method of continuously producing (dynamic dispense method).

As the organic solvent contained in the rinse solution used for the rinse treatment after the development process in the solvent development process, for example, among the organic solvents listed as the organic solvents used in the organic developer, those having difficulty in dissolving the resist pattern may be appropriately used. Can be selected and used. A known additive can be added to the rinse solution, if necessary. Examples of the additive include a surfactant. As the surfactant, a nonionic surfactant is preferable, and a nonionic fluorine-based surfactant or a nonionic silicon-based surfactant is more preferable. When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0.5% by mass with respect to the total amount of the rinse liquid. % Is more preferable.
The rinsing treatment (cleaning treatment) using the rinsing liquid can be carried out by a known rinsing method. Examples of the rinsing treatment method include a method of continuously spraying the rinsing liquid on a support rotating at a constant speed (rotary coating method) and a method of immersing the support in the rinsing liquid for a certain period of time (dip method). , A method of spraying a rinse liquid on the surface of the support (spray method) and the like.

<< Photoresist composition >>
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 according to the present invention is a resin in which an acid is generated by exposure and the solubility in a developing solution is changed by the action of the acid, and the solubility in the developing solution is changed by the action of the acid ( A), a photoresist composition containing an acid generator (B) that generates an acid upon exposure, a photodegradable base (D1), a solvent (S) and a compound (X).
The photoresist composition according to the present invention contains a base material component (A) (hereinafter, resin (A)) whose solubility in a developing solution is changed by the action of an acid.

<Resin (A)>
In the present invention, the photoresist composition contains a resin (A) (hereinafter, also referred to as “component (A)”) whose solubility in a developing solution is changed by the action of an acid. The component (A) of the present invention is not particularly limited as long as it is soluble in the solvent (S) described later and can be used in the photolithography step. In particular, a resin whose solubility in a developing solution can be changed by the action of an acid is preferable. When a resin whose solubility in a developer can be changed by the action of an acid is blended with an acid generator (B) described later in a photoresist composition, the film formed is selectively exposed to form a film. The exposed or unexposed areas inside can be selectively solubilized with alkali. In this case, a pattern having a desired shape can be formed by contacting the selectively exposed film with an alkaline developer to remove the exposed portion or the unexposed portion.

In the present invention, the resin (A) contains the following resin (A1) (hereinafter, also referred to as "(A1) component").
Resin (A1) includes a structural unit (a10) represented by the general formula below (A10-1), those containing structural units derived from styrene ^{(a st)} is preferred.

(Constituent unit (a10))
The structural unit (a10) is represented by the following formula (a10-1).

[式中、Ｒは、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｙａ^ｘ１は、単結合又は２価の連結基であり、Ｗａ^ｘ１は、（ｎ_ａｘ１＋１）価の芳香族炭化水素基であり、ｎ_ａｘ１は、１〜３の整数である。]

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms, Ya ^x1 is a single bond or a divalent linking group, and Wa x1 is ^{a Wa x1.} , (N _ax1 + 1) valent aromatic hydrocarbon group, n _ax1 is an integer of 1-3. ]

In the formula (a10-1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halide group having 1 to 5 carbon atoms.
The alkyl group having 1 to 5 carbon atoms of R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, or n-. Examples thereof include a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an iso-pentyl group, and a neopentyl group.
The alkyl halide group having 1 to 5 carbon atoms of R is a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable. As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable from the viewpoint of industrial availability.

In the above formula (a10-1), Ya ^x1 is a single bond or a divalent linking group.
As the ^{divalent linking group in Ya x1} , for example, a divalent hydrocarbon group which may have a substituent and a divalent linking group containing a heteroatom are preferable.
Divalent hydrocarbon group which may have a substituent: When Ya ^x1 is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group is an aliphatic hydrocarbon group. It may be an aromatic hydrocarbon group.

In Ya ^x1 , the aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like.
The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and 1 to 3 carbon atoms. Is most preferable.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [−CH ₂ −], an ethylene group [− (CH ₂ ) ₂ −], and a trimethylene group [ − (CH ₂ ) ₃ −], tetramethylene group [− (CH ₂ ) ₄ −], pentamethylene group [− (CH ₂ ) ₅ −] and the like can be mentioned.
The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4, and most preferably 3. ..
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, and -C (CH ₃ ). Alkylene methylene groups such as _2- , -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _{2-, etc.;-} CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH ₃ ) CH _2- , -C (CH ₂₎ CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) Examples thereof include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ − and −CH ₂ CH (CH ₃ ) CH ₂ CH _{2 −.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.
The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, a carbonyl group and the like.

As the aliphatic hydrocarbon group containing a ring in the structure, an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from the aliphatic hydrocarbon ring) and an alicyclic hydrocarbon group are linear or branched. Examples thereof include a group bonded to the terminal of a chain-shaped aliphatic hydrocarbon group, a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, and the like. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic type or a monocyclic type. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

The alicyclic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxy group, a carbonyl group and the like. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable. As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group and a tert-butoxy group are more preferable. The methoxy group and the ethoxy group are most preferable. Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable. Examples of the alkyl halide group as the substituent include a group in which a part or all of the hydrogen atom of the alkyl group is substituted with the halogen atom. The cyclic aliphatic hydrocarbon group may have a part of carbon atoms constituting the ring structure substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, -O -, - C (= O) -O -, - S -, - S (= O) 2 -, - S (= O) 2 -O- are preferred.

The aromatic hydrocarbon group of Ya ^x1 is a hydrocarbon group having at least one aromatic ring. The aromatic ring group is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be a polycyclic type or a monocyclic type. 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. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specifically, the aromatic ring is an aromatic hydrocarbon ring such as benzene, naphthalene, anthracene, or phenanthrene; an aromatic heterocycle in which a part of carbon atoms constituting the aromatic hydrocarbon ring is replaced with a heteroatom, or the like. Can be mentioned.
Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Specifically, the aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); an aromatic containing two or more aromatic rings. A group obtained by removing two hydrogen atoms from a compound (for example, biphenyl, fluorene, etc.); a hydrogen atom of a group (aryl group or heteroaryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring. Aromatic group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc. A group obtained by removing one hydrogen atom from the group) and the like. The alkylene group bonded to the aryl group or the heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

The aromatic hydrocarbon group may have a hydrogen atom substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxy group and the like.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable. Examples of the alkoxy group, halogen atom and alkyl halide group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

Divalent linking group containing a hetero atom: When Ya ^x1 is a divalent linking group containing a hetero atom, -O-, -C (= O) -O-, -C are preferable as the linking group. (= O)-, -OC (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H is an alkyl group, acyl group, etc. of which may be substituted with a _{substituent), -. S -, -} S (= O) 2 -, - S (= O) 2 -O-, the formula ^{-Y 21 -O-Y 22 -,} - Y ²¹ -O-, -Y ^21- C (= O) -O-, -C (= O) -O-Y ²¹ -,-[Y ^21- C (= O) -O] _{m "} -Y ^{22 -, - Y 21 -O-C} (= O) -Y 22 - or _{^{-Y 21 -S (= O) 2}} -O-Y 22 - group [wherein represented ^{by, Y 21} and ^{Y 22} each It is a divalent hydrocarbon group which may have a substituent independently, O is an oxygen atom, and m "is an integer of 0 to 3. ] Etc. can be mentioned.
The divalent linking group containing the hetero atom is -C (= O) -NH-, -C (= O) -NH-C (= O)-, -NH-, -NH-C (= NH). )-, The H may be substituted with a substituent such as an alkyl group or an acyl. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms. Formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - C (= O) -O-Y 21 -, - [Y 21 - _{^{C (= O) -O] m}} "-Y 22 -, - Y 21 -O-C (= O) -Y 22 - or _{^{-Y 21 -S (= O) 2}} -O-Y 22 - in, Y ²¹ and Y ²² are divalent hydrocarbon groups which may independently have a substituent. The divalent hydrocarbon group is mentioned in the description as the divalent linking group. ones as .Y ²¹ (the optionally substituted hydrocarbon group or divalent to have a) may be mentioned, preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, more preferably a linear alkylene group having 1 to 5 carbon atoms, particularly preferred .Y ²² is a methylene group or an ethylene group is preferably a linear or branched aliphatic hydrocarbon group, methylene group, ethylene A group or an alkylmethylene group is more preferable. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and methyl. . group is most preferred formula _{^{- [Y 21 -C (= O}} ) -O] m "-Y 22 - in the group represented by, m" is an integer of 0-3, 0-2 in integer preferably there, more preferably 0 or 1, 1 is particularly preferred that is, the formula ^{-. [Y 21 -C (=} O) -O] m "-Y 22 - Examples of the group represented by the formula -Y ^{21 -C (= O) -O-} Y 22 - is particularly desirable. Among them, the formula _{- (CH 2) a '-C} (= O) -O- (CH 2) b' - a group represented by are preferred. In the above formula, a'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1.

Ya ^x1 includes a single bond, an ester bond [-C (= O) -O-], an ether bond (-O-), -C (= O) -NH-, and a linear or branched alkylene group. , Or a combination thereof, and among them, a single bond is particularly preferable.

In the formula (a10-1), Wa ^x1 is an aromatic hydrocarbon group having a (n _{ax1 + 1) valence.}
Examples of the aromatic hydrocarbon group in Wa ^x1 include a group obtained by removing _{(n ax1 + 1) hydrogen atoms from the aromatic ring.} The aromatic ring here is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be a monocyclic type or a polycyclic type.
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. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced with heteroatoms. Can be mentioned. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

In the above formula (a10-1), n _ax1 is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. A specific example of the structural unit represented by the general formula (a10-1) is shown below. In the formula below, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit (a10) contained in the component (A1) may be one type or two or more types.
Among the above, the structural unit (a10) is preferably a structural unit containing a hydroxystyrene skeleton, and particularly preferably a structural unit represented by the following general formula (a10-1-0).

［式中、Ｒ^ｓｔは、水素原子又はメチル基を表す。ｍ_０１は１〜３の整数を表す。］

[In the formula, R ^st represents a hydrogen atom or a methyl group. m ₀₁ represents an integer of 1 to 3. ]

The proportion of the constituent unit (a10) in the component (A1) is preferably 55 to 95 mol%, preferably 60 to 90 mol%, based on the total (100 mol%) of all the constituent units constituting the component (A1). Is more preferable, and 65 to 85 mol% is particularly preferable.
By setting the ratio of the structural unit (a10) to be equal to or higher than the lower limit of the preferable range, the sensitivity, development characteristics, effect of suppressing the occurrence of defects, etc. are further improved, and on the other hand, the ratio is set to be equal to or lower than the upper limit of the preferable range. As a result, lithography characteristics such as dimensional uniformity are further improved.

(Constituent unit ( ^ast ))
The component (A1) may further have a structural unit ( ^ast ) derived from styrene. In the structural unit ( ^ast ), the "constituent unit derived from styrene" is a configuration in which the ethylenic double bond of styrene and a styrene derivative (however, hydroxystyrene is not included) is cleaved. It shall include units.
Here, the "styrene derivative" means that the hydrogen atom bonded to the α-position of styrene is substituted with another substituent such as a halogen atom, an alkyl group or an alkyl halide group, and hydrogen of a phenyl group of styrene. It is assumed that the atom is substituted with a substituent such as a lower alkyl group having 1 to 5 carbon atoms.
Examples of the halogen atom include a chlorine atom, a fluorine atom and a bromine atom, and a fluorine atom is preferable.
The "α-position of styrene" refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.

Included in the structural unit ^{(a st),} structural units represented by the following general formula ^{(a st -1) (a st} 1) can be preferably exemplified.

［式中、Ｒは、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基を表し；Ｒ^２は、炭素数１〜５のアルキル基を表し；ｑは、０又は１〜２の整数を表す。］

[In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group ^{having 1 to 5 carbon atoms; R 2} represents an alkyl group having 1 to 5 carbon atoms; q is. Represents an integer of 0 or 1-2. ]

R may be the same as R of the general formula (a10-1).
q is an integer of 0 or 1-2. Of these, q is preferably 0 or 1, and is particularly preferably industrially 0.
When ^{q is 1, the substitution position of R 2} may be any of the o-position, m-position, and p-position, and when q is 2, any substitution position can be combined. ..

As the structural unit ( ^ast ), one type or a mixture of two or more types can be used.
(A1) When component comprises a structural unit ^{(a st),} the proportion of the structural unit ^{(a st)} on the combined total of all structural units constituting the component (A1) is preferably from 1 to 25 mol%, 5 It is more preferably ~ 25 mol%, most preferably 10-25 mol%. Within this range, the heat resistance effect is enhanced when the photoresist composition is formed, and at the same time, the balance with other constituent units is also good.

Component (A1), within the range not impairing the effects of the present invention may contain other structural unit other than the above essential constitutional units (a10) and the structural unit (a ^st).
As such a structural unit, is not limited particularly as long as the other structural unit which can not be classified as essential constituent units (a10) and the structural unit (a ^st) above, KrF positive excimer laser, such as an ArF excimer laser It is used for the photoresist resin of the above, and many conventionally known ones can be used.
In the present invention, (A1) component, the structural unit (a1) 'lactone-containing cyclic group containing an acid-decomposable group that exhibits increased polarity by the action of an acid, carbonate-containing cyclic group or, or -SO 2 _- containing Constituent unit (a2)'including a cyclic group (however, excluding those corresponding to the above-mentioned structural unit (a1)'), structural unit (a3)' including a polar group-containing aliphatic hydrocarbon group (however, the above-mentioned (Excluding those corresponding to (a1)'and (a2)'), the structural unit (a4)' including an acid non-dissociable cyclic group, and the like may be further included.

(Constituent unit (a1)')
The structural unit (a1)'is a structural unit containing an acid-degradable group whose polarity is increased by the action of an acid.
An "acid-degradable group" is a group having an acid-degradable property in which at least a part of the bonds in the structure of the acid-degradable group can be cleaved by the action of an acid.
Examples of the acid-degradable group whose polarity is increased by the action of an acid include a group which is decomposed by the action of an acid to produce a polar group.
Examples of the polar group include a carboxyl group, hydroxy group, an amino group, such as sulfonic acid group _(-SO 3 H) and the like. Among these, a sulfonic acid group or a polar group containing -OH in the structure (hereinafter, may be referred to as "OH-containing polar group") is preferable, a sulfonic acid group, a carboxyl group, or a hydroxy group is preferable, and a carboxyl group or a carboxyl group or a hydroxy group is preferable. Hydroxy groups are particularly preferred.

More specific examples of the acid-degradable group include a group in which the polar group is protected by an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group).
Here, the "acid dissociative group" is
(I) A group having acid dissociation that allows the bond between the acid dissociating group and an atom adjacent to the acid dissociating group to be cleaved by the action of an acid, or
(Ii) A group capable of cleaving a bond between the acid dissociative group and an atom adjacent to the acid dissociative group by causing a decarboxylation reaction after a part of the bond is cleaved by the action of an acid. ,
It means both of.
The acid dissociable group constituting the acid-degradable group needs to be a group having a lower polarity than the polar group produced by the dissociation of the acid-dissociable group, whereby the acid-dissociable group is caused by the action of the acid. When dissociated, a polar group having a higher polarity than the acid dissociative group is generated, and the polarity is increased. As a result, the polarity of the entire (A1) component increases. As the polarity increases, the solubility in the developer changes relatively, and when the developer is an organic developer, the solubility decreases.

The acid dissociative group is not particularly limited, and those previously proposed as an acid dissociative group of a base resin for a photoresist can be used.
Among the polar groups, the acid dissociable group that protects the carboxyl group or the hydroxy group includes, for example, an acid dissociative group represented by the following formula (a1-r-1)'(hereinafter, for convenience, "acetal-type acid dissociation". (Sometimes called "sexual group").

［式中、Ｒａ’^１、Ｒａ’^２は、水素原子又はアルキル基、Ｒａ’^３は、炭化水素基を表し、Ｒａ’^３は、Ｒａ’^１、Ｒａ’^２のいずれかと結合して環を形成してもよい。＊は、結合位置を意味する。］

Wherein, Ra ^'1, Ra' ² represents a hydrogen atom or an alkyl group, Ra ^'3 represents a hydrocarbon group, Ra' ³ is a ring with either Ra ^'1, Ra' ² of It may be formed. * Means the connection position. ]

'During, Ra' formula (a1-r-1) The ^1, Ra ^'2 alkyl groups, in the description of the α-substituted acrylic acid esters, mentioned as α-position substituent which may be bonded to the carbon atoms of Examples thereof include those similar to the alkyl group, preferably a methyl group or an ethyl group, and most preferably a methyl group.

The ra ^'3 hydrocarbon group is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, a linear or branched alkyl group preferably specifically , Methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, 1,1-dimethylethyl group, 1,1-diethylpropyl group , 2,2-Dimethylpropyl group, 2,2-dimethylbutyl group and the like.

If Ra ^'3 is cyclic hydrocarbon group may be an aromatic or an aliphatic, also be a polycyclic may be a monocyclic. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 8 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and cyclooctane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically. , Adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

If Ra ^'3 is an aromatic hydrocarbon group, specific examples of the aromatic ring contained, benzene, biphenyl, fluorene, naphthalene, anthracene, aromatic hydrocarbon rings phenanthrene; constituting the aromatic hydrocarbon ring An aromatic heterocycle in which a part of the carbon atom to be used is substituted with a heteroatom; etc. can be mentioned. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like.
Specifically, the aromatic hydrocarbon group is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group); a group in which one of the hydrogen atoms of the aryl group is substituted with an alkylene group (an aryl group). For example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

If Ra ^'3 is Ra' to form a ring with either ^1, Ra ^'2 of, a cyclic group, 4- to 7-membered ring is preferred, 4 to 6-membered ring is more preferable. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

Among the polar groups, examples of the acid dissociable group that protects the carboxyl group include an acid dissociative group represented by the following formula (a1-r-2)'(the following formula (a1-r-2). Of the acid dissociable groups represented by)', those composed of alkyl groups may be hereinafter referred to as "tertiary alkyl ester type acid dissociative groups" for convenience).

［式中、Ｒａ’^４〜Ｒａ’^６は、炭化水素基であり、Ｒａ’^５、Ｒａ’^６は、互いに結合して環を形成してもよい。＊は、結合位置を意味する。］

Wherein, Ra ^'4 ~Ra' ⁶ is a hydrocarbon group, Ra ^'5, Ra' ⁶ may be bonded to each other to form a ring. * Means the connection position. ]

Examples of the hydrocarbon group Ra ^'4 ~Ra' ^6, the same as the Ra ^'3 and the like. Ra ^'4 is preferably an alkyl group having 1 to 5 carbon atoms. Ra If ^'5, Ra' ⁶ are bonded to each other to form a ring, and a group represented by the following formula (a1-r2-1) '.
On the other hand, Ra ^'4 ~Ra' ⁶ are not bonded to each other, when an independent hydrocarbon groups include groups represented by the following formula (a1-r2-2) '.

［式中、Ｒａ’^１０は、炭素数１〜１０のアルキル基、Ｒａ’^１１は、Ｒａ’^１０が結合した炭素原子と共に脂肪族環式基を形成する基、Ｒａ’^１２〜Ｒａ’^１４は、それぞれ独立に、炭化水素基を表す。＊は、結合位置を意味する。］

Wherein, Ra ^'10 is an alkyl group having 1 to 10 carbon atoms, Ra' ¹¹ is' group to form an aliphatic cyclic group together with the carbon atom ^{to which 10} are bonded, Ra 'Ra ¹² to Ra' ¹⁴ is , Each independently represents a hydrocarbon group. * Means the connection position. ]

'During, Ra' formula (a1-r2-1) alkyl group of the alkyl group having 1 to 10 carbon atoms ^10, formula (a1-r-1) of the ³ 'Ra' in the straight-chain or branched The groups listed as alkyl groups are preferred. 'During, Ra' formula (a1-r2-1) aliphatic cyclic ^{group 11} constituting the groups listed as cyclic alkyl groups of ³ 'Ra' in the formula (a1-r-1) is preferable.

'During, Ra' formula (a1-r2-2) ¹² and Ra ^'14 are each independently preferably an alkyl group having 1 to 10 carbon atoms, the alkyl group, the formula (a1-r-1 ) and more preferably a group exemplified as straight or branched chain alkyl group having ³ 'Ra' in, more preferably a linear alkyl group of 1 to 5 carbon atoms, is a methyl group or an ethyl group Is particularly preferred.

'During, Ra' formula (a1-r2-2) ¹³ has the formula (a1-r-1) 'in Ra' ³ of cited as hydrocarbon radical straight, branched chain or cyclic alkyl group It is preferable to have. Among these, it is more preferably a group listed as a cyclic alkyl group of Ra ^'3.

Specific examples of the above formula (a1-r2-1)'will be given below. * Means the connection position.

Specific examples of the above formula (a1-r2-2)'will be given below. * Means the connection position.

The acid dissociable group that protects the hydroxy group among the polar groups includes, for example, an acid dissociable group represented by the following formula (a1-r-3)'(hereinafter, for convenience, “tertiary alkyloxycarbonyl”. (Sometimes referred to as an acid dissociative group).

［式中、Ｒａ’^７〜Ｒａ’^９は、アルキル基を表す。＊は、結合位置を意味する。］

Wherein, Ra ^'7 ~Ra' ⁹ represents an alkyl group. * Means the connection position. ]

'During, Ra' formula ^{(a1-r-3) 7} ~Ra '9 is preferably an alkyl group having 1 to 5 carbon atoms, 1 to 3 is more preferable.
The total carbon number of each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

The structural unit (a1)'is a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and its polarity is increased by the action of an acid. A structural unit containing an acid-degradable group; a structural unit in which at least a part of hydrogen atoms in a hydroxy group of a structural unit derived from a hydroxystyrene or a hydroxystyrene derivative is protected by the substituent containing the acid-degradable group; Examples thereof include a structural unit in which at least a part of hydrogen atoms in -C (= O) -OH of a structural unit derived from vinyl benzoic acid or a vinyl benzoic acid derivative is protected by a substituent containing the acid-degradable group. Be done.

Among the above, the structural unit (a1)'is preferably a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent.
As the structural unit (a1)', a structural unit represented by the following formula (a1-1)' or (a1-2)' is preferable.

［式中、Ｒ’は、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基である。Ｖａ^１は、エーテル結合、ウレタン結合、又はアミド結合を有していてもよい２価の炭化水素基であり、ｎ_ａ１は、０〜２であり、Ｒａ^１は、前記式（ａ１−ｒ−１）’〜（ａ１−ｒ−２）’で表される酸解離性基である。Ｗａ^１は、ｎ_ａ２＋１価の炭化水素基であり、ｎ_ａ２は、１〜３であり、Ｒａ^２は、前記式（ａ１−ｒ−１）’又は（ａ１−ｒ−３）’で表される酸解離性基である。］

[In the formula, R'is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group which may have an ether bond, a urethane bond, or an amide bond _{, na 1} is 0 to 2, and Ra ¹ is the above formula (a1-r-). 1) It is an acid dissociative group represented by'to (a1-r-2)'. Wa ¹ _is a _n a2 +1 monovalent hydrocarbon _{group, n a2} is 1 to 3, Table with Ra ^2, the formula (a1-r-1) 'or (a1-r-3)' It is an acid dissociative group. ]

In the formula (a1-1)', the alkyl group having 1 to 5 carbon atoms in R'is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group. Examples thereof include ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The alkyl halide group having 1 to 5 carbon atoms is a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable.
As R', a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable from the viewpoint of industrial availability.

The hydrocarbon group of Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Aliphatic hydrocarbon groups mean hydrocarbon groups that do not have aromaticity. The aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is usually preferably saturated.
More specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in the structure, and the like.
In addition, ^{examples of Va 1} include those in which the divalent hydrocarbon group is bonded via an ether bond, a urethane bond, or an amide bond.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and 1 to 4 carbon atoms. It is most preferably 3.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [−CH ₂ −], an ethylene group [− (CH ₂ ) ₂ −], and a trimethylene group [ − (CH ₂ ) ₃ −], tetramethylene group [− (CH ₂ ) ₄ −], pentamethylene group [− (CH ₂ ) ₅ −] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, and -C (CH ₃ ). Alkylene methylene groups such as _2- , -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _{2-, etc.;-} CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH ₃ ) CH _2- , -C (CH ₂₎ CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) Examples thereof include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ − and −CH ₂ CH (CH ₃ ) CH ₂ CH _{2 −.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

As the aliphatic hydrocarbon group containing a ring in the structure, an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from the aliphatic hydrocarbon ring) and an alicyclic hydrocarbon group are linear or branched. Examples thereof include a group bonded to the terminal of a chain-shaped aliphatic hydrocarbon group, a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, and the like. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic type or a monocyclic type. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

An aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring.
The aromatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, further preferably 5 to 20 carbon atoms, and 6 to 20 carbon atoms. 15 is particularly preferable, and 6 to 10 are most preferable. However, the carbon number does not include the carbon number in the substituent.
Specific examples of the aromatic ring contained in the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; some of the carbon atoms constituting the aromatic hydrocarbon ring are hetero. Aromatic heterocycles substituted with atoms; etc. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like.
Specifically, the aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group). ) Is an aryl group in which one of the hydrogen atoms is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.) A group obtained by removing one more hydrogen atom from the aryl group in the alkyl group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

In the formula (a1-2) ', n _{a2 +1} monovalent hydrocarbon group for Wa ¹ may be an aliphatic hydrocarbon group may be an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, and may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and a linear or branched aliphatic hydrocarbon group. Examples thereof include a group in which a ring-containing aliphatic hydrocarbon group is combined in the structure, and specific examples thereof include a group similar to ^{Va 1 of the above-mentioned formula (a1-1)'.}
The _na2 + 1 valence is preferably 2 to 4 valence, more preferably 2 or 3 valence.
As the formula (a1-2)', a structural unit represented by the following formula (a1-2-01)' is particularly preferable.

In the formula (a1-2-01)', Ra ² is an acid dissociative group represented by the formula (a1-r-1)' or (a1-r-3)'. n _a2 is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. c is an integer of 0 to 3, preferably 0 or 1, and more preferably 1. R'is the same as above.

Specific examples of the formulas (a1-1)'and (a1-2)' are shown below. In each of the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

When the component (A1) has a structural unit (a1)', the ratio of the structural unit (a1)'in the component (A1) is 3 to 25 mol% with respect to all the structural units constituting the component (A1). It is preferably 5 to 20 mol%, more preferably. By setting the value to the lower limit or higher, the lithographic characteristics such as sensitivity, resolution, and LWR are also improved. Further, by setting the value to the upper limit or less, it is possible to balance with other structural units.

(Constituent unit (a2)')
In the present invention, the component (A1), -SO 2 _- containing containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or the structural unit having a heterocyclic group other than these (a2) ' be able to.
-SO 2 of the structural unit (a2) _'- containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or heterocyclic group other than these, for increasing the adhesion to the support of the photoresist film It is effective in.
Incidentally, the structural unit (a1) 'is -SO 2 within the structure _- if it is to have a containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or heterocyclic group other than these, the configuration The unit also corresponds to the constituent unit (a2)', but such a constituent unit corresponds to the constituent unit (a1)' and does not correspond to the constituent unit (a2)'.
The structural unit (a2)'is preferably a structural unit represented by the following formula (a2-1)'.

［式中、Ｒ’は、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｙａ^２１は、単結合又は２価の連結基であり、Ｌａ^２１は、−Ｏ−、−ＣＯＯ−、−ＣＯＮ（Ｒ’）−、−ＯＣＯ−、−ＣＯＮＨＣＯ−又は−ＣＯＮＨＣＳ−であり、Ｒ’は、水素原子又はメチル基を示す。ただし、Ｌａ^２１が−Ｏ−の場合、Ｙａ^２１は−ＣＯ−にはならない。Ｒａ^２１は、−ＳＯ_２−含有環式基、ラクトン含有環式基、カーボネート含有環式基又はこれら以外の複素環式基である。］

[In the formula, R'is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms, Ya ²¹ is a single bond or a divalent linking group, and La ^21. Is -O-, -COO-, -CON (R')-, -OCO-, -CONHCO- or -CONHCS-, where R'indicates a hydrogen atom or a methyl group. However, when La ²¹ is −O−, Ya ²¹ is not −CO−. Ra ²¹ is, -SO 2 _- is containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or heterocyclic group other than these. ]

In the formula (a2-1) ', ^{Ra 21} is, -SO ₂ - containing cyclic group, a lactone-containing cyclic group is preferably a heterocyclic group or a carbonate-containing cyclic group.
The "-SO ₂ -containing cyclic group" refers to a cyclic group containing a ring containing _{-SO 2- in} its ring skeleton, and specifically, the sulfur atom (S) in _{-SO 2-} A cyclic group that forms part of the cyclic skeleton of the cyclic group. _{A ring containing −SO 2} − in its ring skeleton is counted as the first ring, and if it is only the ring, it is a monocyclic group, and if it has another ring structure, it is a polycyclic group regardless of its structure. It is called. The −SO ₂ − containing cyclic group may be monocyclic or polycyclic.
-SO ₂ - containing cyclic group, in particular, -O-SO ₂ - within the ring skeleton cyclic group containing, i.e. -O-SO ₂ - -O-S- medium is a part of the ring skeleton It is preferably a cyclic group containing a sultone ring to be formed. -SO ₂ - containing cyclic group, and more specifically, include groups represented by the following formulas (a5-r-1) ' ~ (a5-r-4)'.

［式中、Ｒａ’^５１は、それぞれ独立に、水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、ヒドロキシ基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基又はシアノ基であり；Ｒ”は、水素原子又はアルキル基であり；Ａ”は、酸素原子若しくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子又は硫黄原子であり、ｎ’は、０〜２の整数である。＊は、結合位置を意味する。］

Wherein, Ra ^'51 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxy group, -COOR ", - OC (= O) R", hydroxyalkyl group or It is a cyano group; R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n. 'Is an integer from 0 to 2. * Means the connection position. ]

In the formulas (a5-r-1)'to (a5-r-4)', A "is referred to as A" in the formulas (a2-r-1)'to (a2-r-7)' described later. The same is true. Ra 'alkyl group in ^51, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR ", - OC (= O) R", The hydroxyalkyl group of the formula below (a2-r-1)' ~ ( a2-r-7) is similar to ²¹ 'Ra' in.
Specific examples of the groups represented by the formulas (a5-r-1)'to (a5-r-4)' are given below. "Ac" in the formula indicates an acetyl group. * Means the connection position.

In the present invention, the structural unit (a2) 'is -SO ₂ - when containing containing cyclic group, -SO ₂ - logP values acrylic acid ester monomer containing containing cyclic group is particularly is less than 1.2 Limited However, among the above, the group represented by the above formula (a5-r-1)'is preferable, and the above formulas (r-sl-1-1), (r-sl-1-18), (r- It is more preferable to use at least one selected from the group consisting of groups represented by any of sl-3-1) and (r-sl-4-1), and the above formula (r-sl-1-1). The group represented by is most preferable.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing −OC (= O) − in its cyclic skeleton. The lactone ring is counted as the first ring, and when it has only a lactone ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of its structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group is not particularly limited, and any lactone-containing cyclic group can be used. Specific examples thereof include groups represented by the following formulas (a2-r-1)'to (a2-r-7)'. * Means the connection position.

［式中、Ｒａ’^２１は、それぞれ独立に、水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、ヒドロキシ基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基又はシアノ基であり；Ｒ”は、水素原子又はアルキル基であり；Ａ”は、酸素原子若しくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子又は硫黄原子であり、ｎ’は、０〜２の整数であり、ｍ’は、０又は１である。］

Wherein, Ra ^'21 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxy group, -COOR ", - OC (= O) R", hydroxyalkyl group or It is a cyano group; R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n. 'Is an integer from 0 to 2, and m'is 0 or 1. ]

In the formulas (a2-r-1)'to (a2-r-7)', A "may contain an oxygen atom (-O-) or a sulfur atom (-S-) and has 1 to 1 carbon atoms. The alkylene group of 5 is an oxygen atom or a sulfur atom. As the alkylene group having 1 to 5 carbon atoms in A ″, a linear or branched alkylene group is preferable, and a methylene group, an ethylene group and an n-propylene group are used. , Isopropylene group and the like. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which -O- or -S- is interposed between the terminal of the alkylene group or a carbon atom, and examples thereof include -O-CH. _{2 -, - CH 2 -O-} CH 2 -, - S-CH 2 -, - CH 2 -S-CH 2 - , and the like. As "A", an alkylene group having 1 to 5 carbon atoms or —O— is preferable, an alkylene group having 1 to 5 carbon atoms is more preferable, and a methylene group is most preferable.

Ra ^'21 are each independently an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR ", - OC (= O) R", a hydroxyalkyl group or a cyano group.
The alkyl group in ra ^'21, preferably an alkyl group having 1 to 5 carbon atoms.
The alkoxy group in the ra ^'21, preferably an alkoxy group having 1 to 5 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, groups of the the Ra 'group and an oxygen atom mentioned as the alkyl group in ²¹ (-O-) are linked and the like.
As the halogen atom in ra ^'21, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom is preferable.
'Examples of the halogenated alkyl group for ^21, the Ra' Ra some or all of the hydrogen atoms of the alkyl group in ²¹ can be mentioned have been substituted with the aforementioned halogen atoms. As the alkyl halide group, an alkyl fluorinated group is preferable, and a perfluoroalkyl group is particularly preferable.

Specific examples of the groups represented by the formulas (a2-r-1)'to (a2-r-7)' are given below. * Means the connection position.

In the present invention, the structural unit (a2)'is preferably a group represented by the above formula (a2-r-1)' or (a2-r-2)', respectively, and the above-mentioned formula (r-lc-1-1). ) Or (r-lc-2-7), respectively, is more preferable.

The "carbonate-containing cyclic group" refers to a cyclic group containing a ring (carbonate ring) containing -OC (= O) -O- in its cyclic skeleton. The carbonate ring is counted as the first ring, and when it has only a carbonate ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of its structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.

Specific examples thereof include groups represented by the following formulas (ax3-r-1)'to (ax3-r-3)'. * Means the connection position.

［式中、Ｒａ’^ｘ３１は、それぞれ独立に、水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、ヒドロキシ基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基又はシアノ基であり；Ｒ”は、水素原子又はアルキル基であり；Ａ”は、酸素原子若しくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子又は硫黄原子であり、ｑ’は、０又は１である。］

[In the formula, ^Ra'x31 are independently hydrogen atom, alkyl group, alkoxy group, halogen atom, alkyl halide group, hydroxy group, -COOR ", -OC (= O) R", hydroxyalkyl group or It is a cyano group; R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and q. 'Is 0 or 1. ]

Specific examples of "A" in the formulas (ax3-r-1)'to (ax3-r-3)' include A in the formulas (a2-r-1)'to (a2-r-7)'. Is the same as. The alkyl group, alkoxy group, halogen atom, alkyl halide group, -COOR ", -OC (= O) R", and hydroxyalkyl group in ^{Ra'x31 are represented by the above formulas (a2-r-1)'to ().} a2-r-7) the same as those described for the ²¹ 'Ra' in the like.

Specific examples of the groups represented by the formulas (ax3-r-1)'to (ax3-r-3)' are given below. * Means the connection position.

The "heterocyclic group" refers to a cyclic group containing one or more atoms other than carbon in addition to carbon, and is a heterocycle listed in (r-hr-1) to (r-hr-16) below, respectively. Examples thereof include a formula group and a nitrogen-containing heterocycle. Examples of the nitrogen-containing heterocyclic group include a cycloalkyl group having 3 to 8 carbon atoms which may be substituted with one or two oxo groups. As the cycloalkyl group, for example, 2,5-dioxopyrrolidine and 2,6-dioxopiperidine are preferable. * Means the connection position.

Specific examples of the structural unit (a2)'having a lactone-containing cyclic group are given below. In each of the following formulas, R ^α is a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit (a2)'may be one type or two or more types.
When the component (A1) has a constituent unit (a2)', the ratio of the constituent unit (a2)' may be 1 to 80 mol% with respect to the total of all the constituent units constituting the component (A1). It is preferably 3 to 70 mol%, more preferably 5 to 65 mol%, and particularly preferably 10 to 60 mol%. By setting it to the lower limit value or more, the effect of containing the constituent unit (a2)'can be sufficiently obtained, and by setting it to the upper limit value or less, it is possible to balance with other constituent units, and various lithographys can be obtained. Good characteristics and pattern shape.

(Constituent unit (a3)')
The structural unit (a3)'is a structural unit containing a polar group-containing aliphatic hydrocarbon group (excluding those corresponding to the above-mentioned structural units (a1)' and (a2)').
When the (A1)'component has the constituent unit (a3)', it is considered that the hydrophilicity of the component (A1) is increased, which contributes to the improvement of the resolution.
Examples of the polar group include a hydroxy group, a cyano group, a carboxyl group, a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is replaced with a fluorine atom, and the like, and a hydroxy group is particularly preferable.

Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group. For example, among a large number of proposed resins for a photoresist composition for an ArF excimer laser. It can be appropriately selected and used. The cyclic group is preferably a polycyclic group, and more preferably has 7 to 30 carbon atoms.

Among them, a configuration derived from an acrylic acid ester containing an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of hydrogen atoms of a hydroxy group, a cyano group, a carboxyl group, or an alkyl group is substituted with a fluorine atom. The unit is more preferred. Examples of the polycyclic group include a group obtained by removing two or more hydrogen atoms from a bicycloalkane, a tricycloalkane, a tetracycloalkane, or the like. Specific examples thereof include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are a group in which two or more hydrogen atoms are removed from adamantane, a group in which two or more hydrogen atoms are removed from norbornane, and a group in which two or more hydrogen atoms are removed from tetracyclododecane. Industrially preferable.

The structural unit (a3)'is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any unit can be used.
The structural unit (a3)'is a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and is a polar group-containing aliphatic hydrocarbon group. A structural unit containing is preferable.
As the structural unit (a3)', when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, the hydroxyethyl ester of acrylic acid is used. The derived structural unit is preferable, and when the hydrocarbon group is a polycyclic group, the structural unit represented by the following formulas (a3-1)'to (a3-5)' is preferable, and the following formula (a3-1) is preferable. The structural unit represented by a3-1)'is more preferable.

［式中、Ｒ’は、上記と同様であり、ｊは、１〜３の整数であり、ｋは、１〜３の整数であり、ｔ’は、１〜３の整数であり、ｌは、１〜５の整数であり、ｓは、１〜３の整数である。］

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

In the formula (a3-1)', j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxy group is bonded to the 3- and 5-positions of the adamantyl group. When j is 1, it is preferable that the hydroxy group is bonded to the 3-position of the adamantyl group.
j is preferably 1 and particularly preferably the hydroxy group is bonded to the 3-position of the adamantyl group.
In the formula (a3-2)', k is preferably 1. The cyano group is preferably attached to the 5- or 6-position of the norbornyl group.
In the formula (a3-3)', t'is preferably 1. l is preferably 1. s is preferably 1. In these, it is preferable that a 2-norbornyl group or a 3-norbornyl group is bonded to the terminal of the carboxyl group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

The structural unit (a3)'contained in the component (A1) may be one type or two or more types.
When the component (A1) contains the constituent unit (a3)', the ratio of the constituent unit (a3)'in the component (A1) is 5 to 5 with respect to the total of all the constituent units constituting the component (A1). It is preferably 50 mol%, more preferably 5 to 40 mol%, still more preferably 5 to 25 mol%.
By setting the ratio of the constituent unit (a3)'to the lower limit value or more, the effect of containing the constituent unit (a3)' can be sufficiently obtained, and by setting it to the upper limit value or less, the balance with other constituent units can be obtained. It becomes easier to take.

The component (A1) may have the following structural unit (a4)'in addition to the structural unit (a1)', (a2)', (a3)'.

(Constituent unit (a4)')
The structural unit (a4)'is a structural unit containing an acid non-dissociative cyclic group. When the component (A1) has a structural unit (a4)', the dry etching resistance of the formed photoresist pattern is improved. In addition, the hydrophobicity of the component (A1) is increased. The improvement of hydrophobicity is considered to contribute to the improvement of resolution, photoresist pattern shape, etc., especially in the case of organic solvent development.
The "acid non-dissociative cyclic group" in the structural unit (a4)'is contained in the structural unit as it is without dissociation even if the acid acts when an acid is generated from the component (B) described later by exposure. It is a cyclic group that remains in.

As the structural unit (a4)', for example, a structural unit derived from an acrylic acid ester containing an acid non-dissociative aliphatic cyclic group is preferable. The cyclic group can be, for example, the same as that exemplified in the case of the above-mentioned structural unit (a1)', and is for ArF excimer laser and KrF excimer laser (preferably for ArF excimer laser). Many of those conventionally known as those used for the resin component of the photoresist composition such as, etc. can be used.
In particular, at least one selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group is preferable in that it is easily available industrially. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.

Specifically, as the structural unit (a4)', those having the structures of the following formulas (a4-1)' to (a4-7)' can be exemplified.

［式中、Ｒ^αは、水素原子、メチル基又はトリフルオロメチル基を示す。］

[In the formula, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group. ]

The structural unit (a4)'contained in the component (A1) may be one type or two or more types.
When the constituent unit (a4)'is contained in the component (A1), the ratio of the constituent unit (a4)'may be 1 to 30 mol% with respect to the total of all the constituent units constituting the component (A1). It is preferably 10 to 20 mol%, more preferably 10 to 20 mol%.

In the photoresist composition of the present invention, one type of component (A) may be used alone, or two or more types may be used in combination.
In the photoresist composition of the present invention, the content of the component (A) may be adjusted according to the required characteristics of the photoresist to be formed, but is 20 with respect to 100 parts by mass of the component (S) described later. It is preferably ~ 100 parts by mass, more preferably 40 to 80 parts by mass, and even more preferably 50 to 70 parts by mass.

<Acid generator (B)>
The photoresist composition of the present invention further contains an acid generator component (hereinafter referred to as "component (B)") in addition to the component (A).
The component (B) is not particularly limited, and those previously proposed as acid generators for photoresists can be used.
Examples of such an acid generator include an onium salt-based acid generator such as an iodonium salt and a sulfonium salt, an oxime sulfonate-based acid generator; and a diazomethane-based acid generator such as bisalkyl or bisarylsulfonyldiazomethane and poly (bissulfonyl) diazomethane. Agents: Various types such as nitrobenzyl sulfonate-based acid generator, imino sulfonate-based acid generator, disulfone-based acid generator and the like can be mentioned. Among them, it is preferable to use an onium salt-based acid generator.

Examples of the onium salt-based acid generator include a compound represented by the following formula (b-1) (hereinafter, also referred to as “component (b-1)”) and a compound represented by the formula (b-2). (Hereinafter, also referred to as “(b-2) component”) or a compound represented by the formula (b-3) (hereinafter, also referred to as “(b-3) component”) can be mentioned.

［式中、Ｒ^１０１、Ｒ^１０４及びＲ^１０５は、それぞれ独立に、ハロゲン原子、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。Ｒ^１０４、Ｒ^１０５は、相互に結合して環を形成していてもよい。Ｒ^１０２は、フッ素原子又は炭素数１〜５のフッ素化アルキル基である。Ｒ^１０６は、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は 置換基を有していてもよい鎖状 アルケニル基であり、ただし、Ｒ^１０６において、Ｓ原子に隣接する炭素原子にはフッ素子は結合していない(フッ素置換されていない)ものとする。Ｙ^１０１は、単結合又は酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３は、それぞれ独立に、単結合、アルキレン基又はフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２は、それぞれ独立に、単結合又は酸素原子である。ｍは、１以上の整数であって、Ｍ’^ｍ＋は、ｍ価のオニウムカチオンである。］

[In the formula, R ¹⁰¹ , R ¹⁰⁴ and R ¹⁰⁵ are each independently a halogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or It is a chain alkenyl group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰⁶ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, however. , R ¹⁰⁶ , it is assumed that no fluorine element is bonded to the carbon atom adjacent to the S atom (no fluorine substitution). Y ¹⁰¹ is a divalent linking group containing a single bond or an oxygen atom. V ^{101 to} V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group. L ^{101 to} L ¹⁰² are each independently a single bond or an oxygen atom. m is an integer of 1 or more, and M'm ⁺ is an m-valent onium cation. ]

{Anion part}
-In the anion part formula (b-1) of the component (b-1), R ¹⁰¹ is a halogen atom, a cyclic group which may have a substituent, and a chain which may have a substituent. It is a chain alkenyl group which may have an alkyl group or a substituent.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable.

Cyclic group which may have a substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. Aliphatic hydrocarbon groups mean hydrocarbon groups that do not have aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

The aromatic hydrocarbon group in R ¹⁰¹ is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, further preferably 5 to 20 carbon atoms, and particularly preferably 6 to 15 carbon atoms. Most preferably, it is 10. However, the carbon number does not include the carbon number in the substituent.
Specifically, as the aromatic ring of the aromatic hydrocarbon group in R ¹⁰¹ , benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or a part of carbon atoms constituting these aromatic rings was substituted with a heteroatom. Examples include aromatic heterocycles. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like.
Specifically, as the aromatic hydrocarbon group in R ^101, a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.) and one of the hydrogen atoms of the aromatic ring are used. Examples thereof include a group substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.). .. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

Examples of the cyclic aliphatic hydrocarbon group in R ¹⁰¹ include an aliphatic hydrocarbon group containing a ring in the structure.
As the aliphatic hydrocarbon group containing a ring in this structure, an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from the aliphatic hydrocarbon ring) and an alicyclic hydrocarbon group are linear or branched. Examples thereof include a group bonded to the terminal of a chain-shaped aliphatic hydrocarbon group, a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, and the like.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 30 carbon atoms. Among them, the polycycloalkane includes a polycycloalkane having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; and a fused ring such as a cyclic group having a steroid skeleton. Polycycloalkanes having a polycyclic skeleton of the system are more preferred.
Among them, as the ^{cyclic aliphatic hydrocarbon group in R 101} , a group obtained by removing one or more hydrogen atoms from monocycloalkane or polycycloalkane is preferable, and a group obtained by removing one hydrogen atom from polycycloalkane is more preferable. Preferably, an adamantyl group and a norbornyl group are particularly preferable, and an adamantyl group is most preferable.

The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms. It is more preferably 1 to 4, and most preferably 1 to 3.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [−CH ₂ −], an ethylene group [− (CH ₂ ) ₂ −], and a trimethylene group [ − (CH ₂ ) ₃ −], tetramethylene group [− (CH ₂ ) ₄ −], pentamethylene group [− (CH ₂ ) ₅ −] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, and -C (CH ₃ ). Alkylene methylene groups such as _2- , -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _{2-, etc.;-} CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH ₃ ) CH _2- , -C (CH ₂₎ CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) Examples thereof include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ − and −CH ₂ CH (CH ₃ ) CH ₂ CH _{2 −.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

Further, ^{the cyclic hydrocarbon group in R 101} may contain a hetero atom such as a heterocycle. Specifically, the lactone-containing cyclic groups represented by the formulas (a2-r-1)'to (a2-r-7)', respectively, and the formulas (a5-r-1)'to (a5-r). _{-SO 2} -containing polycyclic groups represented by -2)', and other heterocyclic groups represented by the following formulas (r-hr-1) to (r-hr-16) can be mentioned. .. * Means the connection position.

Examples of the substituent in the cyclic group of R ¹⁰¹ include an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxy group, a carbonyl group, a nitro group and the like.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable.
As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group are more preferable, and methoxy. Groups and ethoxy groups are most preferable.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable.
The alkyl halide group as a substituent includes an alkyl group having 1 to 5 carbon atoms, for example, a part or all of hydrogen atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group. Examples thereof include groups substituted with the halogen atom.
The carbonyl group as a substituent is a group that substitutes the _{methylene group (−CH 2−) constituting the cyclic hydrocarbon group.}

Chain-like alkyl group which may have a substituent:
The chain alkyl group of R ¹⁰¹ may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decanyl group, an undecyl group, a dodecyl group, a tridecyl group, an isotridecyl group and a tetradecyl group. Examples thereof include a group, a pentadecyl group, a hexadecyl group, an isohexadecyl group, a heptadecyl group, an octadecyl group, a nonadecil group, an icosyl group, a henicosyl group and a docosyl group.
The branched-chain alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples thereof include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

Chain alkenyl group which may have a substituent:
The chain alkenyl group of R ¹⁰¹ may be either linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, and 2 to 5 carbon atoms. It is more preferably 4 and particularly preferably 3. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), a butynyl group and the like. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, a 2-methylpropenyl group and the like.
Among the above, as the chain alkenyl group, a linear alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chain alkyl group or alkenyl group of R ¹⁰¹ include an alkoxy group, a halogen atom, an alkyl halide group, a hydroxy group, a carbonyl group, a nitro group, an amino group, and a cyclic group in ^{R 101.} Can be mentioned.
Among them, R ¹⁰¹ is preferably a cyclic group which may have a substituent and a chain alkyl group which may have a substituent, and a cyclic group which may have a substituent is preferable. More preferably, it is a cyclic hydrocarbon group which may have a substituent.
Among them, a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and a lactone represented by the above formulas (a2-r-1)'to (a2-r-7)' are contained. _{Cyclic groups and -SO 2} -containing polycyclic groups represented by the above formulas (a5-r-1)'to (a5-r-2)' are preferable, and among these, one from polycycloalkane is preferable. _{The groups excluding the above hydrogen atoms and the -SO 2} -containing polycyclic groups represented by the above formulas (a5-r-1)'to (a5-r-2)' are more preferable.

In formula (b-1), Y ¹⁰¹ is a divalent linking group containing a single bond or an oxygen atom.
When Y ¹⁰¹ is a divalent linking group ^{containing an oxygen atom, the Y 101} may contain an atom other than the oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms and the like.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: −O−), an ester bond (−C (= O) −O−), and an oxycarbonyl group (−OC (= O−). )-), Amid bond (-C (= O) -NH-), carbonyl group (-C (= O)-), carbonate bond (-OC (= O) -O-) and other non-hydrocarbons Oxygen atom-containing linking group of the system; Examples thereof include a combination of the oxygen atom-containing linking group of the non-hydrocarbon system and an alkylene group. A sulfonyl group (-SO _2- ) may be further linked to this combination. Examples of the divalent linking group containing such an oxygen atom include linking groups represented by the following formulas (y-al-1) to (y-al-7), respectively.

［式中、Ｖ’^１０１は、単結合又は炭素数１〜５のアルキレン基であり、Ｖ’^１０２は、炭素数１〜３０の２価の飽和炭化水素基である。］

Wherein, V ^'101 is a single bond or an alkylene group having 1 to 5 carbon atoms, V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms. ]

Divalent saturated hydrocarbon group in V ^'102 is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, alkylene group having 1 to 5 carbon atoms Is more preferable.
The alkylene group for V ^'101 and V' ^102, may be straight-chain alkylene group may be a branched chain alkylene group, a linear alkylene group is preferable.

As the alkylene group for V ^'101 and V' ^102, specifically, a methylene group _{[-CH 2 -]; - CH} (CH 3) -, - CH (CH 2 CH 3) -, - C (CH 3) Alkylene methylene groups such as _2- , -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _{2-, etc.; ethylene} Group [-CH ₂ CH _2- ]; -CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH) ₃ ) _{Alkylethylene groups such as CH 2-} ; trimethylene group (n-propylene group) [-CH ₂ CH ₂ CH _2- ]; -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) Alkyl methylene groups such as CH _{2- ; tetramethylene groups [-CH 2} CH ₂ CH ₂ CH _2- ]; -CH (CH ₃ ) CH ₂ CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ Alkyltetramethylene groups such as CH _2- ; pentamethylene groups [-CH ₂ CH ₂ CH ₂ CH ₂ CH _2- ] and the like can be mentioned.

A part of the methylene groups in the alkylene group for V ^'101 or V' ¹⁰² may be substituted by a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably a cyclohexylene group, a 1,5-adamantylene group or a 2,6-adamantylene group.

As Y ¹⁰¹ , a divalent linking group containing an ester bond or a divalent linking group containing an ether bond is preferable, and they are represented by the above formulas (y-al-1) to (y-al-5), respectively. Linking groups are more preferable, and linking groups represented by the above formulas (y-al-1) to (y-al-3) are even more preferable.

In formula (b-1), V ¹⁰¹ is a single bond, an alkylene group or a fluorinated alkylene group. The alkylene group and the fluorinated alkylene group in V ^{101 preferably have 1 to 4 carbon atoms. Examples} of the fluorinated alkylene group in V ¹⁰¹ include a group in which a part or all of hydrogen atoms of the alkylene group in V 101 are substituted with a fluorine atom. Among them, V ¹⁰¹ is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

In formula (b-1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰² is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

Specific examples of the anion portion of the component (b-1) include fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anion and perfluorobutane sulfonate anion when ^{Y 101 is a single bond; Y 101} is When it is a divalent linking group containing an oxygen atom, an anion represented by any of the following formulas (an-1) to (an-3) can be mentioned.

［式中、Ｒ”^１０１は、置換基を有していてもよい脂肪族環式基、前記式（ｒ−ｈｒ−１）〜（ｒ−ｈｒ−６）でそれぞれ表される基、又は置換基を有していてもよい鎖状のアルキル基であり；Ｒ”^１０２は、置換基を有していてもよい脂肪族環式基、前記式（ａ２−ｒ−１）’〜（ａ２−ｒ−７）’でそれぞれ表されるラクトン含有環式基、又は前記式（ａ５−ｒ−１）’〜（ａ５−ｒ−２）’でそれぞれ表される−ＳＯ_２−含有多環式基であり；Ｒ”^１０３は、置換基を有していてもよい芳香族環式基、置換基を有していてもよい脂肪族環式基、又は置換基を有していてもよい鎖状のアルケニル基であり；ｖ”は、それぞれ独立に、０〜３の整数であり、ｑ”は、それぞれ独立に、１〜２０の整数であり、ｔ”は、１〜３の整数であり、ｎ”は、０又は１である。］

[In the formula, R " ¹⁰¹ is an aliphatic cyclic group which may have a substituent, a group represented by the above formulas (r-hr-1) to (r-hr-6), or a substituent, respectively. A chain alkyl group which may have a group; R " ¹⁰² is an aliphatic cyclic group which may have a substituent, said formulas (a2-r-1)'to (a2-). _{A lactone-containing cyclic group represented by r-7)'or a -SO 2} -containing polycyclic group represented by the above formulas (a5-r-1)'to (a5-r-2)', respectively. R " ¹⁰³ is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain which may have a substituent. V "is independently an integer of 0 to 3, q" is independently an integer of 1 to 20, and t "is an integer of 1 to 3. n "is 0 or 1.]

The aliphatic cyclic group which may have a substituent of R " ¹⁰¹ , R" ¹⁰² and R " ¹⁰³ is preferably the group exemplified as the cyclic aliphatic hydrocarbon group in ^{R 101.} Examples of the substituent include those similar to those in which the cyclic aliphatic hydrocarbon group in R ^{101 may be substituted.}
The aromatic cyclic group that may have a substituent at R " ¹⁰³ is preferably a group exemplified as an aromatic hydrocarbon group in the cyclic hydrocarbon group at ^{R 101.} , The same as the substituent which may replace the aromatic hydrocarbon group in ^{R 101.}
The chain-like alkyl group which may have a substituent at R " ¹⁰¹ is preferably a group exemplified as the chain-like alkyl group at ^{R 101. It} has a substituent at ^{R "103.} The good chain alkenyl group is preferably the group exemplified as the chain alkenyl group in ^{R 101.}

-In the anion part formula (b-2) of the component (b-2), R ¹⁰⁴ and R ¹⁰⁵ each independently have a halogen atom and a cyclic group and a substituent which may have a substituent. A chain-like alkyl group which may be present, or a chain-like alkenyl group which may have a substituent, each of which is similar to ^{R 101 in the formula (b-1).} However, R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring.

R ¹⁰⁴ and R ¹⁰⁵ are preferably chain-like alkyl groups which may have a substituent, and are linear or branched-chain alkyl groups, or linear or branched-chain fluorinated alkyl groups. Is more preferable.
The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and further preferably 1 to 3 carbon atoms. The carbon number of the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible because the solubility in the photoresist solvent is also good within the range of the carbon number. Further, in ^{the chain alkyl groups of R 104} and R ^105, the larger the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, and the more transparent to high-energy light of 200 nm or less and electron beams. It is preferable because the property is improved.
The ratio of fluorine atoms in the chain alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are substituted with fluorine atoms. It is a perfluoroalkyl group.

In formula (b-2), V ¹⁰² and V ¹⁰³ are independently single bond, alkylene group, or fluorinated alkylene group, respectively, and the same as ^{V 101 in formula (b-1), respectively.} Can be mentioned.
In formula (b-2), L ¹⁰¹ and L ¹⁰² are independently single bonds or oxygen atoms, respectively.

-In the anion part formula (b-3) of the component (b-3), R ¹⁰⁶ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, and the like. Alternatively, it is a chain alkenyl group that may have a substituent, but in R ¹⁰⁶ , it is assumed that no fluorine is bonded to the carbon atom adjacent to the S atom (no fluorine substitution). .. R ¹⁰⁶ is preferably a cyclic group which may have a substituent and a chain alkyl group which may have a substituent.

Preferred specific examples of the anion portion of the component (b-3) are preferable specific examples of the anion portion of the component (d1-2) among the components (D) described later (d1-2-11) to (d1-d1-). The anion of 2-31) is mentioned, and the anion of (d1-2-11) is most preferable.

{Cation part}
In the formulas (b-1), (b-2) and (b-3), m is an integer of 1 or more, M'm ⁺ is an m-valent onium cation, and the sulfonium cation and the iodonium cation are Preferably mentioned, organic cations represented by the following formulas (ca-1) to (ca-4) are particularly preferable.

［式中、Ｒ^２０１〜Ｒ^２０７及びＲ^２１１〜Ｒ^２１２は、それぞれ独立に、置換基を有していてもよいアリール基、アルキル基又はアルケニル基を表し、Ｒ^２０１〜Ｒ^２０３、Ｒ^２０６〜Ｒ^２０７、Ｒ^２１１〜Ｒ^２１２は、相互に結合して式中の硫黄原子と共に環を形成してもよい。Ｒ^２０８〜Ｒ^２０９は、それぞれ独立に、水素原子又は炭素数１〜５のアルキル基を表し、Ｒ^２１０は、置換基を有していてもよいアリール基、置換基を有していてもよいアルキル基、置換基を有していてもよいアルケニル基、又は置換基を有していてもよい−ＳＯ_２−含有環式基であり、Ｌ^２０１は、−Ｃ（＝Ｏ）−又は−Ｃ（＝Ｏ）−Ｏ−を表し、Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基又はアルケニレン基を表し、ｘは、１又は２であり、Ｗ^２０１は、（ｘ＋１）価の連結基を表す。］

[In the formula, R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² each independently represent an aryl group, an alkyl group or an alkenyl group which may have a substituent, and R ^{201 to} R ²⁰³ and R ²⁰⁶ to R 206. R ²⁰⁷ and R ^{211 to} R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ²¹⁰ may have an aryl group or a substituent which may have a substituent. containing cyclic ^{group, L 201} is, -C (= O) - - alkyl group, a substituted group alkenyl which may have, or may have a substituent group -SO ₂ or -C Represents (= O) -O-, Y ²⁰¹ independently represents an arylene group, an alkylene group or an alkenylene group, x is 1 or 2, and W ²⁰¹ represents a (x + 1) valent linking group. Represent. ]

Examples of the aryl group in R ^{201 to} R ²⁰⁷ and R ^{211 to R 212} include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.
The alkyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² preferably has 2 to 10 carbon atoms.
Examples of the substituent that R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have include an alkyl group, a halogen atom, an alkyl halide group, a carbonyl group, a cyano group, an amino group, an aryl group, and the following formula. Examples thereof include groups represented by (ca-r-1) to (ca-r-7), respectively.

［式中、Ｒ’^２０１は、それぞれ独立に、水素原子、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。］

Wherein, R ^'201 have each independently, a hydrogen atom, which may have a substituent cyclic group which may have a substituent chain alkyl group, or a substituent It is a chain alkenyl group that may be present. ]

R ^'201 substituents cyclic group which may have a substituent and has optionally also good chain alkyl group, or have a substituent which may chain alkenyl groups, above ^{The same as R 101 in} the formula (b-1) of the above can be mentioned. Additionally, R 'as a ²⁰¹ substituents alkyl group which may chain also have a good cyclic group or substituent have, above structural units (a1)' acid-dissociable group in The same can be mentioned.

When R ^{201 to} R ²⁰³ , R ^{206 to} R ²⁰⁷ , and R ^{211 to} R ²¹² are bonded to each other to form a ring together with the sulfur atom in the formula, heteroatoms such as sulfur atom, oxygen atom, and nitrogen atom, and heteroatoms such as sulfur atom and nitrogen atom, and carbonyl _{group, -SO -, - SO 2 -} , - SO 3 -, - COO -, - CONH- , or -N _(R N) - (wherein _{R N} is an alkyl group having 1 to 5 carbon atoms.) It may be bonded via a functional group such as. As the ring to be formed, one ring containing a sulfur atom in the ring skeleton is preferably a 3 to 10-membered ring including a sulfur atom, and preferably a 5- to 7-membered ring. Especially preferable. Specific examples of the formed ring include, for example, a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthene ring, a thianthrene ring, a phenoxatiin ring, a tetrahydrothiophenium ring, and a tetrahydro. Examples include a thiopyranium ring.

R ^{208 to} R ²⁰⁹ independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable, and when they are alkyl groups, they are bonded to each other. A ring may be formed.
R ²¹⁰ may have an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent. -SO ₂ -containing cyclic group.
^Examples of the aryl group in R 210 include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.
The alkyl group in R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group in R ²¹⁰ preferably has 2 to 10 carbon atoms.
As the _{-SO 2} -containing cyclic group which may have a substituent in ^{R 210} , the above-mentioned "-SO ₂ -containing polycyclic group" is preferable, and the formula (a5-r-1)'is used. The group represented is more preferred.

Y ²⁰¹ independently represents an arylene group, an alkylene group or an alkaneylene group.
Examples of the arylene group in Y ²⁰¹ include a group obtained by removing one hydrogen atom from the aryl group exemplified as the aromatic hydrocarbon group in ^{R 101} in the above formula (b-1).
Examples of the alkylene group and the alkaneylene group in Y ^{201 include a chain alkyl group in R 101} in the above formula (b-1) and a group obtained by removing one hydrogen atom from the group exemplified as the chain alkenyl group. ..

Specific examples of suitable cations represented by the formula (ca-1) include cations represented by the following formulas (ca-1-1) to (ca-1-67).

［式中、ｇ１、ｇ２、ｇ３は、繰り返し数を示し、ｇ１は、１〜５の整数であり、ｇ２は、０〜２０の整数であり、ｇ３は、０〜２０の整数である。］

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

［式中、Ｒ”^２０１は、水素原子又は置換基であって、該置換基としては、前記Ｒ^２０１〜Ｒ^２０７及びＲ^２１０〜Ｒ^２１２が有していてもよい置換基として例示したものと同様である。］

[In the formula, R " ²⁰¹ is a hydrogen atom or a substituent, and the substituents are exemplified as the substituents that ^{R 201 to} R ²⁰⁷ and R ^{210 to} R ^{212 may have.} The same is true.]

Specific examples of the suitable cation represented by the formula (ca-2) include a diphenyl iodonium cation and a bis (4-tert-butylphenyl) iodonium cation.

Specific examples of suitable cations represented by the formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

Specific examples of suitable cations represented by the formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

Among the above, the cation portion [( ^{M'm +} ) _{1 / m} ] is preferably a cation represented by the formula (ca-1), and is represented by the formulas (ca-1-1) to (ca-1-67), respectively. The represented cation is more preferred.
Preferred examples of the component (B) include the component (b-3), and in particular, the component (b-3) is an anion represented by (d1-2-11) to (d1-2-31) described later. A combination of the portion and the cation represented by the above formulas (ca-1-1) to (ca-1-16) can be used.

As the component (B), the above-mentioned acid generator may be used alone or in combination of two or more.
The content of the component (B) contained in the photoresist composition is preferably 0.1 to 50 parts by mass, more preferably 0.1 to 40 parts by mass with respect to 100 parts by mass of the component (S) described later.
By setting the content of the component (B) within the above range, pattern formation is sufficiently performed. Further, when each component of the photoresist composition is dissolved in a solvent, a uniform solution can be easily obtained, and the storage safety of the photoresist composition is improved, which is preferable.

<Acid diffusion control agent (D)>
The photoresist composition of the present invention contains an acid diffusion control agent (D) (hereinafter, referred to as “component (D)”). The component (D) acts as a quencher (acid diffusion control agent) that traps the acid generated by exposure in the photoresist composition.
The component (D) of the photoresist composition of the present invention contains a photodisintegrating base (D1) (hereinafter referred to as "component (D1)") which is decomposed by exposure and loses acid diffusion controllability, and further (hereinafter referred to as "component (D1)"). A nitrogen-containing organic compound (D2) (hereinafter, referred to as “(D2) component”) that does not correspond to the D1) component may be contained.

-Regarding the component (D1) By using a photoresist composition containing the component (D1), it is possible to improve the contrast between the exposed portion and the unexposed portion when forming the photoresist pattern.
The component (D1) is not particularly limited as long as it decomposes by exposure and loses acid diffusion controllability, and is a compound represented by the following formula (d1-1) (hereinafter, “component (d1-1)”). The compound represented by the following formula (d1-2) (hereinafter referred to as "(d1-2) component") and the compound represented by the following formula (d1-3) (hereinafter referred to as "(d1-d1-) component"). 3) One or more compounds selected from the group consisting of "components") are preferable.
The components (d1-1) to (d1-3) do not act as a quencher because they decompose in the exposed portion of the photoresist film and lose the acid diffusion controllability (basicity), and as a quencher in the unexposed portion. It works.

［式中、Ｒｄ^１〜Ｒｄ^４は、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。ただし、式（ｄ１−２）中のＲｄ^２における、Ｓ原子に隣接する炭素原子には、フッ素原子は結合していないこととする。Ｙｄ^１は、単結合又は２価の連結基である。ｍは、１以上の整数であって、Ｍ^ｍ＋は、それぞれ独立に、ｍ価の有機カチオンである。］

[In the formula, Rd ^{1 to Rd 4} are a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain which may have a substituent. Alkyl group in the form. However, it is assumed that the fluorine atom is not bonded to the carbon atom adjacent to the S atom in ^{Rd 2} in the formula (d1-2). Yd ¹ is a single bond or divalent linking group. m is an integer of 1 or more, and M ^{m +} is an independently m-valent organic cation. ]

{(D1-1) component}
In the anion part formula (d1-1), Rd ¹ has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may be present.
Among these, ^{as Rd 1} , an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain which may have a substituent may be used. Alkyl groups in the form are preferable. Examples of the substituent that these groups may have include a hydroxy group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluorinated alkyl group, and the above formulas (a2-r-1)'to (a2-r). Examples thereof include a lactone-containing cyclic group represented by -6)', an ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is contained as a substituent, an alkylene group may be used.

As the aromatic hydrocarbon group, a phenyl group or a naphthyl group is more preferable.
The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane.
The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and the like. Linear alkyl groups such as nonyl group and decyl group; 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl Examples thereof include branched alkyl groups such as a group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.
The chain-like alkyl group can have a fluorine atom or a fluorinated alkyl group as a substituent, and the number of carbon atoms of the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and 1 to 1. 4 is more preferable. The fluorinated alkyl group may contain an atom other than the fluorine atom. Examples of the atom other than the fluorine atom include an oxygen atom, a sulfur atom, a nitrogen atom and the like.

Rd ¹ is preferably a fluorinated alkyl group in which some or all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms, and Rd 1 is a hydrogen atom constituting the linear alkyl group. It is particularly preferable that all of them are fluorinated alkyl groups (linear perfluoroalkyl groups) substituted with fluorine atoms.
A preferable specific example of the anion portion of the component (d1-1) is shown below.

In the cation part equation (d1-1), M ^{m +} is an m-valent organic cation.
As ^{the organic cation of M m +,} the same cations as those represented by the above formulas (ca-1) to (ca-4) are preferably mentioned, and the cation represented by the above formula (ca-1) is preferable. More preferably, the cations represented by the above formulas (ca-1-1) to (ca-1-67) are even more preferable.
As the component (d1-1), one type may be used alone, or two or more types may be used in combination.

{(D1-2) component}
In the anion part formula (d1-2), Rd ² has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may be present.
However, it is assumed that the fluorine atom is not bonded (fluorine-substituted) to the carbon atom adjacent to the S atom in ^{Rd 2.} As a result, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the quenching ability as the component (D) is improved.
Rd ² is preferably a chain alkyl group which may have a substituent or an aliphatic cyclic group which may have a substituent. The chain alkyl group preferably has 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. As the aliphatic cyclic group, a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (may have a substituent); one from camphor, etc. It is more preferable that the group is a group excluding the above hydrogen atom.
The hydrocarbon group of Rd ² may have a substituent, and the substituents include the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group ^{) in Rd 1 of the above formula (d1-1).} Examples thereof include the same substituents that the chain alkyl group may have.
A preferable specific example of the anion portion of the component (d1-2) is shown below.

In the cation part formula (d1-2), M ^{m +} is an m-valent organic cation, which is the same as M ^{m +} in the above formula (d1-1).
As the component (d1-2), one type may be used alone, or two or more types may be used in combination.

{(D1-3) component}
In the anion part formula (d1-3), Rd ³ has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It may be a chain alkenyl group, preferably a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group. Among them, the fluorinated alkyl group is preferable, and the same group as the fluorinated alkyl group of ^{Rd 1 is more preferable.}

In formula (d1-3), Rd ⁴ may have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group.
Among them, an alkyl group, an alkoxy group, an alkenyl group, and a cyclic group which may have a substituent are preferable.
The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and the like. Examples thereof include an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. A part of the hydrogen atom of the alkyl group of Rd ⁴ may be substituted with a hydroxy group, a cyano group or the like.
The alkoxy group in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and specifically, the alkoxy group having 1 to 5 carbon atoms is a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, or n-. Examples thereof include a butoxy group and a tert-butoxy group. Among them, a methoxy group and an ethoxy group are preferable.
The alkenyl group in Rd ⁴ is preferably a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group, or a 2-methylpropenyl group. These groups may further have an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms as a substituent.
The cyclic group in Rd ⁴ is an alicyclic group obtained by removing one or more hydrogen atoms from cycloalkanes such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane, or a phenyl group. Aromatic groups such as naphthyl groups are preferred. When Rd ⁴ is an alicyclic group, the photoresist composition is well dissolved in a solvent, so that the lithography characteristics are improved. Further, when Rd ⁴ is an aromatic group, the photoresist composition has excellent light absorption efficiency and good sensitivity and lithography characteristics in lithography using EUV or the like as an exposure light source.

In formula (d1-3), Yd ¹ is a single bond or a divalent linking group.
The ^{divalent linking group in Yd 1} is not particularly limited, but includes a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent and a hetero atom 2 Examples include valuation linking groups.
Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, and even more preferably a methylene group or an ethylene group.
A preferable specific example of the anion portion of the component (d1-3) is shown below.

In the cation part formula (d1-3), M ^{m +} is an m-valent organic cation, which is the same as M ^{m +} in the above formula (d1-1).
As the component (d1-3), one type may be used alone, or two or more types may be used in combination.

As the component (D1), only one of the above components (d1-1) to (d1-3) may be used, or two or more of them may be used in combination.
Among the above, it is preferable to use at least the component (d1-1) as the component (D1).
The content of the component (D1) contained in the photoresist composition is preferably 0.1 to 5 parts by mass and 0.1 to 4 parts by mass with respect to 100 parts by mass of the component (S). Is more preferable, and 0.1 to 3 parts by mass is further preferable.
When the content of the component (D1) is at least a preferable lower limit value, particularly good lithography characteristics and a photoresist pattern shape can be easily obtained. On the other hand, when it is not more than the upper limit value, good sensitivity can be maintained.

(D1) Ingredient manufacturing method:
The method for producing the component (d1-1) and the component (d1-2) is not particularly limited, and the component (d1-1) and the component (d1-2) can be produced by a known method.
The method for producing the component (d1-3) is not particularly limited, and is produced in the same manner as that described in, for example, US Patent Publication No. US2012-01499116.

-Regarding the component (D2) As the acid diffusion control agent component, a nitrogen-containing organic compound component (hereinafter, referred to as "(D2) component") that does not correspond to the above-mentioned component (D1) may be further contained.
The component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not correspond to the component (D1), and any known component may be used. Among them, aliphatic amines and aromatic amines are preferable.

The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.
Examples of the aliphatic amine include _{an amine (alkylamine or alkylalcoholamine) in which at least one hydrogen atom of ammonia NH 3} is replaced with an alkyl group or a hydroxyalkyl group having 12 or less carbon atoms, or a cyclic amine.
Specific examples of alkylamines and alkylalcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di. Dialkylamines such as -n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine , Tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, tri-n-dodecylamine and other trialkylamines; diethanolamine, triethanolamine, diisopropanolamine, tri Alkyl alcohol amines such as isopropanolamine, di-n-octanolamine and tri-n-octanolamine can be mentioned. Among these, trialkylamines having 5 to 10 carbon atoms are more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

Examples of the cyclic amine include a heterocyclic compound containing a nitrogen atom as a hetero atom. The heterocyclic compound may be a monocyclic compound (aliphatic monocyclic amine) or a polycyclic compound (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and specifically, 1,5-diazabicyclo [4.3.0] -5-nonen and 1,8-diazabicyclo [5]. .4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane and the like.

Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, and tris {2. -(1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris [2- {2- (2-hydroxy) Examples thereof include ethoxy) ethoxy} ethyl] amine and triethanolamine triacetate, and triethanolamine triacetate is preferable.

Further, as the component (D2), an aromatic amine may be used.
Aromatic amines include 4-dimethylaminopyridine, pyrrol, indol, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidin, 2,4-diamino-6. -Phenyl-1,3,5-triazine and the like can be mentioned, 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 is more preferred.

As the component (D2), one type may be used alone, or two or more types may be used in combination.
When the photoresist composition contains the component (D2), the component (D2) can be used in the range of 0.005 to 3 parts by mass with respect to 100 parts by mass of the component (S). Within the above range, the shape of the photoresist pattern, stability over time after exposure, and the like are improved.

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

The photoresist composition of the present invention contains any suitable cross-linking agent (E1) (hereinafter referred to as "(E1) component") capable of cross-linking the resin component (A) in the presence of an acid. Can be done. Non-limiting examples of the component (E1) include melamine, methylol, glycoluril, polymer glycoluril, benzoguanamine, urea, resins containing bidroxyalkylamide, epoxy and epoxyamimin resins, blocked isocyanates. And divinyl monomers, etc., and monomeric melamines such as hexamethoxymethylmelamine, glycoluril derivatives, or aromatic methylols such as 2,6-bishydroxymethylp-cresol can be used.
As the component (E1) used in the present invention, a glycoluril derivative is preferable, and tetrakis (methoxymethyl) glycoluril, tetrakis (butoxymethyl) glycoluril and the like are particularly preferable.

As the component (E1), one type may be used alone, or two or more types may be used in combination. When the photoresist composition contains the component (E1), the content of the component (E1) is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the component (A), and is preferably 3 to 30 parts by mass. It is more preferably 5 to 20 parts by mass.

The photoresist composition of the present invention may contain a compound (E2) having one or more polar groups in order to satisfy excellent adhesion. When the photoresist composition contains a compound having one or more polar groups, the amount of solvent remaining in the photoresist layer at the time of forming the photoresist pattern is reduced, and the adhesion between the support and the photoresist pattern is improved. improves.
The compound having one or more polar groups is preferably selected from the group in which the polar group consists of a hydroxy group, an amino group, a mercapto group, a carboxyl group, and a sulfonic acid group, and the hydroxy group, the amino group, and the carboxyl group are selected. It is more preferably selected from the group consisting of groups, most preferably hydroxy groups.
The compound having one or more polar groups preferably has a molecular weight of 2,000 or less, more preferably 1,500 or less, and has a molecular weight of 1,000 or less, from the viewpoint of improving the adhesion to the support. Those are more preferable.
Further, the compound having one or more polar groups is preferably a compound having one or more hydroxy groups from the aspect of improving adhesion to the support, and at this time, the compound having one or more hydroxy groups is , The compound represented by the formula (e-1) is preferable.

［式中、Ａは、ｐ価の炭素数１〜１０の直鎖状炭化水素基又は炭素数３〜１０の分岐鎖状炭化水素基であり、ｐは、１〜３の整数である。］

[In the formula, A is a linear hydrocarbon group having a p-valent carbon number of 1 to 10 or a branched chain hydrocarbon group having a p-valent carbon number of 3 to 10, and p is an integer of 1 to 3. ]

In A of the formula (e-1), the number of carbon atoms of the linear hydrocarbon group is preferably 2 to 8, and more preferably 4 to 6.
In A of the formula (e-1), the number of carbon atoms of the branched chain hydrocarbon group is preferably 4 to 8, and more preferably 5 to 6.
The p of the formula (e-1) is preferably 2 to 3, and more preferably 3.

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 a compound represented by the formula (e-2). preferable.

［式中、Ｂは、ｑ価の炭素数１〜１０の直鎖状炭化水素基又は炭素数３〜１０の分岐鎖状炭化水素基であり、ｑは、１〜３の整数である。］

[In the formula, B is a linear hydrocarbon group having a q valence of 1 to 10 carbon atoms or a branched chain hydrocarbon group having 3 to 10 carbon atoms, and q is an integer of 1 to 3. ]

In B of the above formula (e-2), the number of carbon atoms of the linear hydrocarbon group is preferably 2 to 8, and more preferably 4 to 6.
In B of the above formula (e-2), the number of carbon atoms of the branched chain hydrocarbon group is preferably 4 to 8, and more preferably 5 to 6.
The q of the formula (e-2) is preferably 2 to 3, and more preferably 3.

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 a compound represented by the formula (e-3). preferable.

［式中、Ｄは、ｒ価の炭素数１〜１０の直鎖状炭化水素基又は炭素数３〜１０の分岐鎖状炭化水素基であり、ｒは、１〜３の整数である。］

[In the formula, D is a linear hydrocarbon group having an r-valent carbon number of 1 to 10 or a branched chain hydrocarbon group having an r-valent carbon number of 3 to 10, and r is an integer of 1 to 3. ]

In D of the above formula (e-3), the number of carbon atoms of the linear hydrocarbon group is preferably 2 to 8, and more preferably 4 to 6.
In D of the above formula (e-3), the number of carbon atoms of the branched chain hydrocarbon group is preferably 4 to 8, and more preferably 5 to 6.
The r of the formula (e-3) is preferably 2 to 3, and more preferably 3.

As the component (E2), one type may be used alone, or two or more types may be used in combination.
When the photoresist composition contains the component (E2), the content of the component (E2) is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the component (S), and is preferably 3 to 30 parts by mass. Is more preferable, and 5 to 20 parts by mass is further preferable. Within the above range, the adhesion of the thick-film photoresist layer to the support is improved.

<Solvent (S)>
The photoresist composition of the present invention can be produced by dissolving a photoresist material in a solvent (S) (hereinafter, referred to as "component (S)").
The component (S) may be any as long as it can dissolve each component to be used to form a uniform solution, and is not particularly limited. Therefore, among those conventionally known as solvents for photoresist compositions. Any of these can be appropriately selected and used, but can be selected from the range satisfying the requirements of the present invention in which an appropriate amount of residual solvent remains in the resist film before pattern formation.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, 2-heptanone; ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1, Polyhydric alcohols such as 2-hexanol and 1,3-butanediol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, the polyvalent alcohols Alternatively, a derivative of a polyhydric alcohol such as a monomethyl ether, a monoethyl ether, a monopropyl ether, a monoalkyl ether such as a monobutyl ether, or a compound having an ether bond such as a monophenyl ether of the compound having an ester bond; Cyclic ethers and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethylbenzyl ether , Cresylmethyl ether, diphenyl ether, dibenzyl ether, phenetol, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, simene, mesityrene and other aromatic solvents; dimethylsulfoxide (DMSO); propylene carbonate And so on.

The compound having an ester bond may be mono or diacetate represented by the following general formula (s-1).

［式中、ｎ１は、１又は２であり、Ｒ^ｓは、置換基を有していてもよい炭素数５〜１０のアルキル基であり、前記炭素数は、前記置換基の炭素数を含む。］

Wherein, n1 is 1 or 2, R ^s is optionally substituted alkyl group which may having 5 to 10 carbon atoms, wherein the number of carbon atoms includes carbon atoms of the substituent .. ]

The substituent of the alkyl group having 5 to 10 carbon atoms, which may have a substituent of R ^s , may replace a part or all of the hydrogen atom of the alkyl group of ^{R s.} It may replace the carbon atom of the alkyl group main chain of ^{R s.}
Examples of the substituent that substitutes a part or all of the hydrogen atom of the alkyl group of R ^s include a lower alkyl group having 1 to 5 carbon atoms, a lower alkoxy group having 1 to 5 carbon atoms, a fluorine atom, and a fluorine atom. Examples thereof include a fluorinated lower alkyl group having 1 to 5 carbon atoms and an oxygen atom (= O). Among them, a lower alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group (-OCH ₃ ) is more preferable.
Examples of the substituent of the alkyl group backbone carbon atoms of R ^s, for example, a divalent linking group containing a hetero atom is preferable. Examples of the divalent linking group containing the hetero atom include -O-, -C (= O) -O-, -C (= O)-, -OC (= O) -O-, and "-A". -O (oxygen atom) -B- (where A and B are divalent hydrocarbon groups that may independently have substituents) "and the like. As the A and the substituent which may be possessed by B, the ones same as those of the substituent groups for substituting a part or all of the hydrogen atoms of the alkyl group of R ^s and the like.

Examples of the mono or diacetate represented by the general formula (s-1) include 3-methoxybutyl acetate (abbreviation = MBA; boiling point = 171 ° C.; SP value = 871) and dipropylene glycol methyl ether acetate (abbreviation). = DPMA; boiling point = 213 ° C; SP value = 871), propylene glycol diacetate (abbreviation = PGDA; boiling point = 190 ° C; SP value = 960), 1,3-butylene glycol diacetate (abbreviation = 1,3BGDA; boiling point) = 232 ° C; SP value = 1011), cyclohexanol acetate (abbreviation = CHXA; boiling point = 173 ° C; SP value = 918), ethylene glycol monobutyl ether acetate (abbreviation = BMGAC; boiling point = 188 ° C; SP value = 885), Examples thereof include diethylene glycol monoethyl ether acetate (abbreviation = EDGAC; boiling point = 217 ° C; SP value = 901), diethylene glycol monobutyl ether acetate (abbreviation = BDGAC; boiling point = 247 ° C; SP value = 894).

As the component (S), DPMA, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), 2-heptanone, 1,2-hexanediol, 1,3-butanediol and the like are preferable.

As the component (S), one type may be used alone, or two or more types may be used as a mixed solvent. The amount of the component (S) used is not particularly limited, and is a concentration that can be applied to a support or the like, and is appropriately set according to the coating film thickness. The component (S) can be used in a range where the solid content concentration of the photoresist composition is 30 to 70% by mass, and more preferably, it can be used in a range where the solid content concentration is 5 to 20% by mass.

<Compound (X)>
The photoresist composition of the present invention contains at least one compound (X) represented by the following formula (x-1) in order to improve the properties of the photoresist composition.

［式中、Ｒ^１〜Ｒ^４は、それぞれ独立に、ヒドロキシ基又は炭素数１〜５のアルキル基であり、Ｒ^５及びＲ^６は、それぞれ独立に、水素、炭素数１〜５のアルキル基又はヒドロキシ基で置換された炭素数１〜１０のアルキル基であり、ａ、ｂ、ｃ及びｄは、それぞれ独立に、０〜３の整数であり、ｅ及びｆは、それぞれ独立に、１〜２の整数である。］

[In the formula, R ^{1 to} R ⁴ are independently hydroxy groups or alkyl groups having 1 to 5 carbon atoms, and R ⁵ and R ⁶ are independently hydrogen and alkyl groups having 1 to 5 carbon atoms, respectively. Alternatively, it is an alkyl group having 1 to 10 carbon atoms substituted with a hydroxy group, a, b, c and d are independently integers of 0 to 3, and e and f are independently 1 to 1, respectively. It is an integer of 2. ]

The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and more preferably a linear alkyl group. Specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group and a neopentyl group.
The alkyl group having 1 to 10 carbon atoms substituted with the hydroxy group is preferably a linear or branched alkyl group having 1 to 10 carbon atoms substituted with one or more hydroxy groups, and is linear. Alkyl groups are more preferred.
Each of the above R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ may be the same as or different from each other, and is preferably the same as each other. Each of the a and b, c and d, e and f may be the same as or different from each other, and is preferably the same as each other.
As the compound (X), a compound represented by the following formula is preferable.

［前記式において、Ｒ^５及びＲ^６は、前記式（ｘ−１）における定義と同一である。］

[In the above formula, R ⁵ and R ⁶ are the same as the definitions in the above formula (x-1). ]

As the compound (X), a compound represented by the following formula is also preferable.

［前記式において、Ｒ^３及びＲ^４は、前記式（ｘ−１）における定義と同一である。］

[In the above formula, R ³ and R ⁴ are the same as the definitions in the above formula (x-1). ]

Specific examples of compound (X) are given below.

By using the compound (X), the effect of improving sensitivity can be obtained, and the shape can be maintained while maintaining high resolution.
As the component (X), one type may be used alone, or two or more types may be used as a mixture. The content of the component (X) contained in the photoresist composition is preferably 1 to 25 parts by mass, more preferably 1 to 20 parts by mass with respect to 100 parts by mass of the component (A). It is more preferably ~ 15 parts by mass.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these examples.

<Preparation of photoresist composition>
Each component as shown in Tables 1 and 2 below was mixed and dissolved to prepare a photoresist composition of each example.

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

(A) Component Polymer compound containing the following structural units in a ratio of x: y (A) -1:

(B) Ingredients An acid generator represented by the following chemical formula.

(D) Component An acid diffusion control agent represented by the following chemical formula.

(D2) -1: Triethylamine

(E1) Ingredient

テトラキス(メトキシメチル)グリコールウリル

Tetrakis (methoxymethyl) glycol uryl

(S) Component (S) -1: Dipropylene glycol methyl ether acetate (DPMA)
(S) -2: 1,2-Hexanediol (S) -3: 2-Heptanone (S) -4: 1,3-Butandiol (S) -5: Dipropylene glycol methyl ether (S) -6: γ-Butyrolactone (GBL)
(S) -7: Propylene carbonate (S) -8: Propylene glycol monomethyl ether acetate (PGMEA)
(S) -9: Propylene glycol monomethyl ether (PGME)

(X) component

２，２’−ジメチル−４，４’−（フルオレン−９，９−ジイル)ジフェノール

2,2'-dimethyl-4,4'-(fluorene-9,9-diyl) diphenol

４，４’−（９−フルオレニリデン)ジフェノール

4,4'-(9-fluorenylidene) diphenol

ビスフェノキシエタノールフルオレン

Bisphenoxyethanol fluorene

４，４’−シクロヘキシリデンビスフェノール

4,4'-Cyclohexylidene bisphenol

<Measurement of residual solvent in the film>
Each of the compositions shown in Tables 1 and 2 was applied onto an 8-inch silicon wafer and baked at 100 ° C. for 60 seconds so that the film thickness was 300 nm. The photoresist film on the wafer was cut out and the amount of residual solvent was measured with a GC-flame ionization detector. The values are shown in Table 3 below.

<Formation of photoresist pattern>
The compositions of Tables 1 and 2 are respectively applied to a 12-inch silicon wafer using a coater, prebaked (PAB) at 100 ° C. for 60 seconds on a hot plate, and dried. , A photoresist film having a film thickness of 300 nm was formed.
Next, a KrF excimer laser (248 nm) was applied to the photoresist film by a KrF exposure apparatus NSR-S210D (manufactured by Nikon; NA (numerical aperture) = 0.82, σ = 0.90) with a mask pattern (binary). ) Was selectively irradiated.
Then, a post-exposure heating (PEB) treatment was performed at 110 ° C. for 90 seconds.
Next, using a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) as a developing solution, alkaline development was performed at 23 ° C. for 60 seconds. went. Then, pure water was used to rinse with water for 30 seconds to dry.

<Characteristic evaluation of photoresist pattern>
The characteristics of the photoresist pattern formed as described above were evaluated as follows.

(Standing wave value)
The standing wave (SW) is a numerical value of the cross-sectional shape of the formed photoresist pattern, and is indicated by the width of the thickest part of the cross section (MAX) / the width of the thinnest part of the cross section (MIN). The closer it is to 0.0, the more ideal it is.

(Depth of focus (DOF))
In order to form a fine pattern, the depth of focus must be large.
Using a scanning electron microscope (SEM), the photoresist patterns formed from the photoresist compositions of Examples 1 to 9 and Comparative Examples 1 to 7 were observed, and the SW value and DOF were determined.
This is shown in Table 4 below.

Although suitable examples of the present invention have been described above, the present invention is not limited to these examples. Configurations can be added, omitted, replaced, and other modifications without departing from the spirit of the present invention.

Claims (4)

(I) A step of forming a photoresist film on a support using a photoresist composition;
(Ii) A photoresist pattern forming method comprising a step of exposing the photoresist film; and (iii) a step of developing the exposed photoresist film to form a photoresist pattern.
The photoresist composition comprises a resin (A) whose solubility in a developing solution changes due to the action of an acid, an acid generator (B) that generates an acid upon exposure, a photodegradable base (D1), a solvent (S) and Contains the compound (X) represented by the following formula (x-1),
A method for forming a photoresist pattern, wherein the amount of the solvent remaining on the photoresist film formed in the step (i) is 910 ppm or more.

[In the formula, R ^{1 to} R ⁴ are independently hydroxy groups or alkyl groups having 1 to 5 carbon atoms, and R ⁵ and R ⁶ are independently hydrogen and alkyl groups having 1 to 5 carbon atoms, respectively. Alternatively, it is an alkyl group having 1 to 10 carbon atoms substituted with a hydroxy group, a, b, c and d are independently integers of 0 to 3, and e and f are independently 1 to 1, respectively. It is an integer of 2. ] In the formula, a, b, c and d are 0, e and f are 1, and R ⁵ and R ⁶ are independently hydrogen _{or-(CH 2} ) _n- OH (n is). The photoresist pattern forming method according to claim 1, wherein the photoresist pattern is (an integer of 1 to 5). The photoresist base (D1) is one or more compounds selected from the group composed of compounds represented by the following formulas (d1-1), formulas (d1-2) and formulas (d1-3). The photoresist pattern forming method according to claim 1 or 2, wherein the photoresist pattern is formed.

[In the formula, Rd ^{1 to Rd 4} are a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl which may have a substituent. It is a group, however, in Rd ² in the formula (d1-2), a fluorine atom is not bonded to the carbon atom adjacent to the S atom, Yd ¹ is a single bond or a divalent linking group, and m. Is an integer of 1 or more, and M ^{m +} is an independently m-valent organic cation. ] Any of claims 1 to 3, wherein the resin (A) whose solubility in a developing solution is changed by the action of an acid contains a polymer compound having a structural unit represented by the following formula (a10-1). The method for forming a photoresist pattern according to item 1.

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms, Ya ^x1 is a single bond or a divalent linking group, and Wa x1 is ^{a Wa x1.} , (N _ax1 + 1) valent aromatic hydrocarbon group, n _ax1 is an integer of 1-3. ]