TWI701506B - Method of forming resist pattern and resist composition - Google Patents

Abstract

A method of forming a resist pattern, including: forming a resist film on a substrate using a resist composition which generates acid upon exposure and exhibits changed solubility in a developing solution under the action of acid; exposing the resist film; and developing the resist film to form a resist pattern, the resist composition containing an acid generator and the acid generator containing a compound (b1) having a sulfonium cation which contains an ether group and a compound (b2) represented by general formula (b2) (R²¹ represents a cyclic group which may have a substituent, R²² represents a fluorine atom or a fluorinated alkyl group of 1 to 5 carbon atoms, Y²¹ represents a single bond or a divalent linking group containing O; V²¹ represents a single bond, an alkylene group or a fluorinated alkylene group; and M’^m+ represnets an organic cation having a valency of m).

Description

Photoresist pattern forming method and photoresist composition

The invention relates to a photoresist pattern forming method and a photoresist composition.

In the photolithographic etching technology, for example, after a photoresist film formed of a photoresist material is formed on a substrate, a mask for forming a certain pattern is interposed on the photoresist film, and the process is performed with radiation such as light and electron rays. Selective exposure, and then performing development processing, and the step of forming a photoresist pattern of a certain shape on the aforementioned photoresist film.

The photoresist material whose characteristic is changed so that the exposed part is dissolved in the developing liquid is called positive type, and the photoresist material whose characteristic is changed so that the exposed part is insoluble in the developing liquid is called negative type.

In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, advances in lithographic etching technology have rapidly promoted the miniaturization of patterns.

The general method of miniaturization is to shorten the wavelength of the exposure light source (increasing energy). Specifically, the ultraviolet rays represented by g-line and i-line were previously used, but KrF excimer lasers and ArF excimer lasers are now being used Mass production of semiconductor components. Also, began to review electron beams, EUV (extreme ultraviolet) and X-rays with shorter wavelengths (higher energy) than these excimer lasers.

Therefore, the photoresist material is required to have sensitivity relative to the exposure light sources, and can reproduce the lithographic etching characteristics such as the resolution of fine-sized patterns.

However, various lithographic etching characteristics are affected by the standing waves generated by the reflection of light on the surface of the substrate or photoresist film. Therefore, attempts have been made to suppress the influence of light scattered or reflected in all directions by, for example, the shape of the substrate surface such as the stepped substrate, or the thickness of the photoresist film.

For example, Patent Document 1 discloses a method of controlling light absorption by mixing the photosensitive resistor composition with a dye resin in order to reduce the influence of the reflection from the substrate or the photoresist film surface.

Prior art literature Patent literature

Patent Document 1: Japanese Patent Application Publication No. 10-186647

However, in the method described in Patent Document 1, there is a problem that the lithographic etching characteristics that reduce the resolution are reduced along with the introduction of the dye resin. In addition, the dye in the photoresist film is sublimated due to the heat treatment when the photoresist film is formed, so there is a problem of contamination of the heating plate.

In view of the foregoing, the subject of the present invention is to provide Even when the reflectivity of the support is relatively high, a photoresist pattern forming method and photoresist composition with good photolithographic etching characteristics can be used.

The first aspect of the present invention is a method for forming a photoresist pattern, which is characterized in that it includes the use of light that generates acid by exposure on the support and changes its solubility with respect to the developer by the action of the acid. In the photoresist pattern forming method of the step of forming a photoresist film, the step of exposing the photoresist film, and the step of developing the photoresist film to form a photoresist pattern, the photoresist composition The acid generator contains an acid generator, and the aforementioned acid generator contains a compound (b1) having an ether group-containing cation and a compound (b2) represented by the following general formula (b2).

[式中，R²¹為可具有取代基之環式基；R²²為氟原子或碳數1~5之氟化烷基；Y²¹為單鍵或含有氧原子之二價的連結基；V²¹為單鍵、伸烷基、或氟化伸烷基；M’^m+為m價之有機陽離子]。

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence].

The second aspect of the present invention is a photoresist composition, which is characterized in that an acid is generated by exposure, and is changed relative to The soluble photoresist composition of the developer solution contains an acid generator, and the aforementioned acid generator contains a compound (b1) having an ether group-containing cation, which is represented by the following general formula (b2) Compound (b2).

[式中，R²¹為可具有取代基之環式基；R²²為氟原子或碳數1~5之氟化烷基；Y²¹為單鍵或含有氧原子之二價的連結基；V²¹為單鍵、伸烷基、或氟化伸烷基；M’^m+為m價之有機陽離子]。

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence].

In the scope of this specification and patent application, "aliphatic" refers to a substance that does not possess aromatic radicals, compounds, etc. in the concept of aromatics.

"Alkyl" is a monovalent saturated hydrocarbon group including linear, branched, and cyclic without special indication.

"Alkylene" does not specifically indicate that the following systems include linear, branched, and cyclic divalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.

The "halogenated alkyl group" is a group in which part or all of the hydrogen atoms in the alkyl group are replaced by halogen atoms, such as fluorine, chlorine, bromine, and iodine atoms.

"Fluorinated alkyl" or "fluorinated alkylene" refers to the A group in which part or all of the hydrogen atoms are replaced by fluorine atoms.

"Constructive unit" refers to the monomer unit that constitutes a polymer compound (resin, polymer, copolymer).

"The structural unit derived from acrylate" refers to the structural unit formed by the cracking of the ethylenic double bond of acrylate.

"Acrylate" is a compound in which the hydrogen atom of the carboxyl terminal of acrylic acid (CH ₂ =CH-COOH) is replaced by an organic group.

The acrylate may be such that the hydrogen atom bonded to the carbon atom at the α position is substituted by a substituent. The substituent (R ^α ) of the hydrogen atom bonded to the carbon atom at the α position is an atom or group other than a hydrogen atom, such as an alkyl group with 1 to 5 carbons, a halogenated alkyl group with 1 to 5 carbons, and a hydroxyl group. Alkyl and so on. In addition, the carbon atom at the α -position of the acrylate is not specified as the carbon atom to which the carbonyl group is bonded.

Hereinafter, the acrylate in which the hydrogen atom bonded to the carbon atom at the α -position is replaced by a substituent is referred to as an α- substituted acrylate. In addition, including acrylate and α- substituted acrylate are collectively referred to as "( α- substituted) acrylate".

"Constituent units derived from vinyl benzoic acid or vinyl benzoic acid derivatives" refer to the constituent units formed by the cleavage of the ethylenic double bond of vinyl benzoic acid or vinyl benzoic acid derivatives.

"Vinyl benzoic acid derivative" refers to a product in which the hydrogen atom at the α position of vinyl benzoic acid is replaced by other substituents such as alkyl and halogenated alkyl groups, and the concept of such derivatives. Derivatives of these such as a hydrogen atom, α position of the hydrogen atoms may be substituted benzoic acid substituted vinyl group of the carboxyl group is substituted with an organic group thereof, α position of the hydrogen atoms may be substituted with the substituted vinyl benzoic acid Substituents other than hydroxyl and carboxyl groups are bonded to the benzene ring. In addition, the α -position (the carbon atom at the α -position) refers to the carbon atom bonded to the benzene ring unless otherwise specified.

"Styrenic derivative" refers to a product in which the hydrogen atom at the α -position of styrene is substituted by other substituents such as alkyl and halogenated alkyl.

"Constituent units derived from styrene" and "Constituent units derived from styrene derivatives" refer to the constituent units formed by cleavage of the ethylenic double bond of styrene or styrene derivatives.

The alkyl group used as the substituent at the α position is preferably a linear or branched alkyl group, specifically, for example, an alkyl group having 1 to 5 carbon atoms (methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl) and the like.

Moreover, as the position of the α-substituted halogenated alkyl group with a specific example, the aforementioned "As the α position by an alkyl substituent group," part or all of the hydrogen atoms are substituted with a halogen atom of the group. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, and iodine atom. Particularly preferred is a fluorine atom.

Moreover, as the α position of the alkyl group substituted with a hydroxyalkyl specific example, the aforementioned "As the α position by an alkyl substituent group," part or all of the hydrogen atoms are substituted by a hydroxyl group. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, most preferably 1.

When it is stated that "may have a substituent", it includes both the hydrogen atom (-H) being substituted by a monovalent group and the methylene group (-CH ₂ -) being substituted by a divalent group.

"Exposure" is a concept that includes total radiation exposure.

The present invention can provide a photoresist pattern forming method and a photoresist composition that have good lithographic etching characteristics even when the reflectivity of the support is high.

Form of invention "Photoresist Pattern Formation Method"

The first aspect of the present invention is a method for forming a photoresist pattern, which is characterized by using a photoresist that generates an acid by exposure on a support and changes the solubility of the developer with respect to the developer by the action of the acid. In the photoresist pattern forming method of the step of forming a photoresist film, the step of exposing the photoresist film, and the step of developing the photoresist film to form a photoresist pattern, the photoresist composition It contains an acid generator, and the aforementioned acid generator contains a compound (b1) having an ether group-containing cation and a compound (b2) represented by the following general formula (b2).

[式中，R²¹為可具有取代基之環式基；R²²為氟原子或碳數1~5之氟化烷基；Y²¹為單鍵或含有氧原子之二價的連結基；V²¹為單鍵、伸烷基、或氟化伸烷基； M’^m+為m價之有機陽離子]。

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence].

The photoresist pattern forming method of the present invention includes a step of forming a photoresist film using the photoresist composition of the present invention described later on a support, and a step of exposing the photoresist film, and developing the photoresist film And the step of forming a photoresist pattern.

For example, the photoresist pattern forming method of the present invention is carried out as follows.

First, use a spin coater or the like to coat the photoresist composition of the present invention described later on the support, and then apply heating for 40 to 120 seconds, preferably 60 to 90 seconds under temperature conditions of 80 to 150°C (post- apply bake (PAB)) treatment to form a photoresist film.

Secondly, with respect to the photoresist film, exposure devices such as KrF exposure devices, ArF exposure devices, electronic line drawing devices, EUV exposure devices, etc. are used for exposure with or without a mask (pattern mask) that forms a certain pattern. After performing selective exposure under the hood for drawing by direct irradiation of electron beams, for example, heating at 80-150°C for 40-120 seconds, preferably 60-90 seconds (post-exposure bake (PAB)) deal with.

Next, the aforementioned photoresist film is subjected to development processing.

In the development process, an alkaline developing solution is used in the alkaline developing step, and a developing solution (organic developing solution) containing an organic solvent is used in the solvent developing step.

After the development process, it is preferable to implement a cleaning process. In the cleaning process, it is preferable to use pure water for washing in the alkaline development step, and it is preferable to use a cleaning solution containing an organic solvent in the solvent development step.

The solvent development step can be carried out after the aforementioned development treatment or cleaning treatment Yes, the supercritical fluid is used to remove the developing solution or cleaning solution attached to the pattern.

Drying is performed after development or cleaning. Depending on the situation, a heat treatment (post bake) may be performed after the above-mentioned development treatment. In this way, the photoresist pattern can be obtained.

The support in the present invention is not particularly limited, and previously known ones can be used, but when a support with a reflectance of 1.0% or more of light with respect to the wavelength of the exposure light source is used, an excellent effect can be exerted. The "support" in the present invention refers to an anti-reflection film forming substrate on which an anti-reflection film described later is formed on a substrate described later.

In the past, in order to suppress the influence of the standing wave generated by the light reflected on the surface of the substrate or photoresist film, methods such as forming an anti-reflection film were used.

However, in order to obtain the desired pattern, it is better to make the coating amount of the anti-reflective film forming material smaller than usual, or depending on the type of substrate, even when the anti-reflective film is formed, the reflectivity can still be higher than normal. A photoresist pattern is formed on the support whose reflectivity is less than 1.0%.

Since the present invention can meet various needs, even if a support with a reflectance of 1.0% or more relative to the light of the wavelength of the exposure light source is used, a photoresist pattern with excellent lithographic etching characteristics can be formed.

The reflectance can be calculated by the conventional method by measuring the refractive index (n value) and the light absorption rate (k value) when the light of the exposure wavelength is irradiated on the support.

For example, when a KrF excimer laser is used as the exposure wavelength, the reflectance can be calculated by the conventional method by measuring the refractive index (n value) and the light absorption rate (k value) of the support when light with a wavelength of 248nm is actually measured .

In the present invention, an excellent effect can be exhibited when the reflectance of the support is 1.0% or more, it is more pronounced when the reflectance is 3.0% or more, particularly when it is 4.0% or more, and the effect is more pronounced when the reflectance is 5.0% or more.

The substrate is a substrate used for electronic components, or a certain wiring pattern formed on the substrate. More specifically, such as silicon wafers, copper, chromium, iron, aluminum and other metal substrates, or glass substrates. The material of the wiring pattern can be copper, aluminum, nickel, gold, etc., for example. In addition, various stepped substrates can be used.

Anti-reflection films such as inorganic and/or organic films. Inorganic films such as inorganic anti-reflection films (inorganic BARC). Organic films such as organic anti-reflective film (organic BARC), or organic film of bottom organic film of multilayer photoresist method.

The multilayer photoresist method means that after at least one layer of organic film (bottom organic film) and at least one layer of photoresist film (upper photoresist film) are provided on a substrate, the photoresist pattern formed on the upper photoresist film is The mask is a method of drawing the bottom organic film, which can form a pattern with a high aspect ratio. That is, the multilayer photoresist method can use the underlying organic film to ensure the required thickness, so the photoresist film can be thinned to form a fine pattern with a high aspect ratio.

Basically, the multilayer photoresist method is divided into a method with a double-layer structure of an upper photoresist film and a bottom organic film (double photoresist method), and a middle layer between the upper photoresist film and the bottom organic film Layer (metal thin film, etc.) with a multilayer structure of three or more layers (three-layer photoresist method).

The wavelength for exposure is not particularly limited. ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electronic beam), X-ray, Radiation such as soft X-ray is performed. In the present invention, the applicability of KrF excimer laser, ArF excimer laser, EB or EUV is higher, and the applicability of KrF excimer laser is particularly high.

The exposure method of the photoresist film can be general exposure (dry exposure) in inert gas such as air or nitrogen, or liquid immersion exposure (Liquid Immersion Lithography).

In liquid immersion exposure, a solvent (liquid immersion medium) with a refractive index greater than that of air is first filled between the photoresist film and the lens at the bottom of the exposure device, and exposure is carried out in this state (immersion exposure). Exposure method.

The liquid immersion medium is preferably a solvent having a refractive index greater than that of air and a refractive index smaller than that of the photoresist film to be exposed. There is no particular limitation when the refractive index of this type of solvent is within the aforementioned range.

Solvents with a refractive index greater than that of air and a refractive index smaller than that of the aforementioned photoresist film, such as water, fluorine-based inactive liquids, silicon-based solvents, and hydrocarbon-based solvents.

Specific examples of fluorine-based inactive liquids include liquids containing 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 , C ₅ H ₃ F ₇ and the like as main components. , Preferably having a boiling point of 70 to 180°C, more preferably 80 to 160°C. When the fluorine-based inactive liquid has a boiling point in the above range, it is preferable that the solvent used in the liquid immersion can be removed in a simple manner after the exposure is completed.

The fluorine-based inactive liquid is particularly preferably a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are replaced by fluorine atoms. Specific examples of the perfluoroalkyl compound are perfluoroalkyl ether compounds or perfluoroalkylamine compounds.

In addition, the specific aforementioned perfluoroalkyl ether compounds such as perfluoro(2-butyl- Tetrahydrofuran) (boiling point 102°C), the aforementioned perfluoroalkylamine compound such as perfluorotributylamine (boiling point 174°C).

From the viewpoints of cost, safety, environmental issues, versatility, etc., the liquid immersion medium preferably uses water.

The alkali imaging solution used in the development process of the alkali imaging step is, for example, a 0.1-10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.

The organic solvent containing the organic developer liquid used in the development process of the solvent development step may be a substance that can dissolve the substrate component (the substrate component before exposure) in the photoresist composition, and it may be known Appropriate selection among organic solvents. Specifically, polar solvents and hydrocarbon solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents can be used.

If necessary, the organic developer can add known additives. Such additives are surfactants. The surfactant is not particularly limited. For example, ionic or nonionic fluorine-based and/or silicon-based surfactants can be used.

When the surfactant is added, the added amount is generally 0.001 to 5 mass% relative to the total amount of the organic developer, preferably 0.005 to 2 mass%, and more preferably 0.01 to 0.5 mass%.

The development process can be implemented by a known development method, such as a method in which the support is immersed in a developer solution for a certain period of time (dipping method), and a method in which the surface of the support body bears the developer liquid for a certain period of time by surface tension ( Puddle method), a method of spraying the mist of the developer on the surface of the support (spray method). The developer is sprayed on the support at a certain speed at a certain speed while scanning. The method (dynamic injection method) and so on.

The cleaning treatment (cleaning treatment) using the cleaning solution can be performed by a known cleaning method. The method is, for example, the method of continuously applying the cleaning liquid on the support rotating at a certain speed (rotary coating method), the method of immersing the support in the cleaning liquid for a certain period of time (dipping method), and the mist-like cleaning liquid Spray on the surface of the support (spray method), etc.

The photoresist composition used in the photoresist pattern forming method of the present invention will be described below.

The photoresist composition used in the photoresist pattern forming method of the present invention is characterized in that an acid is generated by exposure, and the solubility of the developer with respect to the developer is changed by the action of the acid. The acid generator contains a compound (b1) having an ether group-containing cation and a compound (b2) represented by the general formula (b2).

In the present invention, the photoresist composition preferably contains a resin component (hereinafter referred to as "substrate component" or "(A) component") that changes the solubility with respect to the developer liquid by the action of an acid as described later.

After using this type of photoresist composition to form a photoresist film, when selectively exposing the photoresist film, acid is generated in the exposed area, and the effect of the acid changes the ratio of component (A) relative to the developer solution. Solubility, and the unexposed part does not change the solubility of the component (A) with respect to the developer solution, so there will be a difference in solubility between the exposed part and the unexposed part with respect to the developer solution. Therefore, when the photoresist film is developed, the photoresist composition will dissolve and remove the exposed part to form a positive photoresist pattern when the photoresist composition is of a positive type, and will dissolve and remove the unexposed pattern when the photoresist composition is of a negative type. Part to form a negative photoresist pattern.

In this manual, the light of the positive photoresist pattern is formed by dissolving and removing the exposed part The resist composition is called a positive resist composition, and the resist composition that dissolves and removes the unexposed parts to form a negative resist pattern is called a negative resist composition.

The photoresist composition in the present invention can be a positive photoresist composition or a negative photoresist composition.

In addition, the photoresist composition of the present invention can be used to form a photoresist pattern in an alkaline development step using an alkaline developer, or a developer containing an organic solvent when used in the development process (Organic developer) solvent development step.

In the present invention, the photoresist composition is a substance having acid generating energy that generates acid by exposure. In addition to the acid generator contained in the photoresist composition, the component (A) can also generate acid by exposure.

Specifically, the photoresist composition of the present invention may be: (1) the acid generator is an acid generator component (B) (hereinafter referred to as (B) component) that generates acid by exposure, and (A) component is used Components that do not generate acid by exposure; (2) The component (A) is a component that generates acid by exposure, and it also contains the component (B).

That is, the component (A) in the case of (2) above is "a base material component that generates acid by exposure and changes its solubility with respect to the developer by the action of the acid". When the component (A) is a substrate component that generates acid by exposure and changes its solubility with respect to the developer by the action of the acid, the component (A) described below is preferably the component that generates acid by exposure , And by the action of acid to change the solubility of the polymer compound relative to the developer. This type of polymer compound can use a tree with a structural unit that generates acid by exposure. As the constituent unit of fat, which generates acid by exposure, a known substance can be used.

The photoresist composition of the present invention is particularly preferably the above-mentioned (1).

<Acid generator component: (B) component>

The photoresist composition of the present invention is an acid generator component containing a compound (b1) having an ether group-containing cation and a compound (b2) represented by the general formula (b2) (hereinafter referred to as "(B) component) ").

[式中，R²¹為可具有取代基之環式基；R²²為氟原子或碳數1~5之氟化烷基；Y²¹為單鍵或含有氧原子之二價的連結基；V²¹為單鍵、伸烷基、或氟化伸烷基；M’^m+為m價之有機陽離子]。

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence].

[Compound (b1)]

<Cation part>

The compound (b1) "hereinafter referred to as "(b1)") is a compound having an ether group-containing alumium cation.

The (b1) of the present invention is, for example, a chlorine compound having a cation containing ether group. The ether group-containing alumium cation is, for example, the following general formula (b1-1-1)~(b1- 1-3) The cation represented by each.

[式中，R¹¹~R¹⁵及R²⁰~R²¹表示各自獨立的可具有取代基之芳基、烷基或鏈烯基，R¹¹~R¹⁵及R²⁰~R²¹可相互鏈結與式中之硫原子形成環。但R¹¹~R¹³、R¹⁴~R¹⁵、R²⁰~R²¹中，各自之中至少一個為含有醚基；R¹⁶~R¹⁷表示各自獨立之氫原子或碳數1~5之烷基，R¹⁹為可具有取代基之芳基、烷基、鏈烯基或含有-SO₂-之環式基，L¹⁸表示-C(=O)-或-C(=O)-O-，Y³⁰表示各自獨立的伸芳基、伸烷基或伸鏈烯基，x為1或2，W³⁰表示(x+1)價之連結基]。

[In the formula, R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ represent independent aryl, alkyl or alkenyl groups that may have substituents, and R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ can be linked to each other The sulfur atom in the formula forms a ring. However, at least one of R ¹¹ to R ¹³ , R ¹⁴ to R ¹⁵ , and R ²⁰ to R ²¹ contains an ether group; R ¹⁶ to R ¹⁷ represent independent hydrogen atoms or an alkyl group with 1 to 5 carbon atoms , R ¹⁹ is optionally substituted aryl, alkyl, alkenyl or cyclic group containing -SO ₂ -, L ¹⁸ represents -C(=O)- or -C(=O)-O-, Y ³⁰ represents each independent aryl, alkylene or alkenylene group, x is 1 or 2, and W ³⁰ represents a (x+1) valent linking group].

The aryl group in R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ is an unsubstituted aryl group having 6 to 20 carbon atoms, preferably phenyl and naphthyl.

The alkyl group in R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ is a chain or cyclic alkyl group, preferably having 1 to 30 carbon atoms.

The alkenyl groups of R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ preferably have 2 to 10 carbons.

R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ may have substituents such as, when at least one of R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ contains an ether group, other alkyl groups, halogen atoms, halogenated alkyl groups, A carbonyl group, a cyano group, an amino group, an aryl group, and an arylthio group are groups represented by the following formulas (ca-r-1) to (ca-r-7).

The aryl group in the arylthio group used as the substituent is, for example, the same as those exemplified for R ¹¹ , specifically, phenylthio or biphenylthio.

[式中，R’²⁰¹為各自獨立的氫原子、可具有取代基之環式基、鏈狀烷基或鏈狀鏈烯基]。

[In the formula, ^R'201 is each independent hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group or a chain alkenyl group].

R ^'201 may have a substituent of a cyclic group such as in the later-described formula (b2) R ²¹ the same thing, may have substituent group of an alkyl chain, alkenyl chain, or may have a substituent group, such as the , The same thing as R ¹¹ in the above formula (b1-1-1), and a cyclic group which may have a substituent or a chain alkyl group which may have a substituent, for example, with the following formula (a1-r-2 ) Represents the same acid-dissociable group.

When R ¹¹ ~R ¹⁵ and R ²⁰ ~R ²¹ are mutually bonded to form a ring with the sulfur atom in the formula, heteroatoms such as sulfur atom, oxygen atom, nitrogen atom, etc. may be interposed, or carbonyl group, -SO-, -SO ₂ -, -SO ₃ -, -COO-, -CONH- or -N(R _N )- (the _RN is an alkyl group with 1 to 5 carbon atoms) and other functional groups are bonded. The ring formed is a ring whose ring skeleton contains a sulfur atom in the formula, preferably a 3-10 membered ring containing a sulfur atom, and particularly preferably a 5-7 membered ring. Specific examples of the formed ring include a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a phenothioxan ring, and a tetrahydrothiophenium ring , Tetrahydrothiopyrylium ring, etc.

R ¹⁶ to R ¹⁷ represent each independent hydrogen atom or an alkyl group with 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group with 1 to 3 carbon atoms, which may bond to each other to form a ring when they are alkyl groups.

R ¹⁹ is the aryl group may have a substituent group, an optionally substituted alkyl group, the alkenyl group may have a substituent group, the group may have a substituent, or the containing -SO ₂ - of the cyclic group.

The aryl group in R ¹⁹ is, for example, an unsubstituted aryl group having 6 to 20 carbon atoms, preferably phenyl and naphthyl.

The alkyl group in R ¹⁹ is a chain or cyclic alkyl group, preferably one having 1 to 30 carbon atoms.

The alkenyl group in R ¹⁹ preferably has 2 to 10 carbon atoms.

The -SO ₂ -containing cyclic group which may have a substituent in R ^{19 is} , for example, the same as the "-SO ₂ -containing cyclic group" of Ra ²¹ in the general formula (a2-1) described later, preferably It is a base represented by the general formula (a5-r-1) described later.

Y ³⁰ represents an arylene group, an alkylene group or an alkenylene group independently of each other.

The aryl group in Y ³⁰ is, for example, a group obtained by removing one hydrogen atom from an aryl group used as an aromatic hydrocarbon group as listed in R ²¹ in the formula (b2) described later.

The alkylene group and alkenylene group in Y ³⁰ are, for example, the same as the aliphatic hydrocarbon group used as the divalent hydrocarbon group of Va ¹ in the general formula (a1-1) described later.

In the aforementioned formula (b1-1-3), x is 1 or 2.

W ³⁰ is (x+1) valence, that is, the linking base of divalent or trivalent.

The divalent linking group in W ³⁰ is preferably a divalent hydrocarbon group that may have a substituent, for example, the same hydrocarbon group as Ya ^{21 of the} general formula (a2-1) described later. The divalent linking group of W ³⁰ may be linear, branched or cyclic, preferably cyclic. Among them, the group obtained by combining two carbonyl groups at both ends of the aryl group is preferred. Arylenes such as phenylene, naphthylene, etc., particularly preferably phenylene.

The trivalent linking group of W ^{30 is} , for example, a group obtained by removing one hydrogen atom from the divalent linking group of W ³⁰ , a group obtained by bonding the aforementioned divalent linking group to the aforementioned divalent linking group, and the like. The trivalent linking group of W ³⁰ is preferably a group obtained by bonding an aryl group to two carbonyl groups.

In the present invention, the cation part of (b1) is preferably the cation part represented by the above general formula (b1-1-1).

The cation moiety represented by the general formula (b1-1-1) is more preferably the general formula (b1-1-1-1) or (b1-1-1-2) shown below.

[式中，R⁴⁰¹為可具有取代基之烴基，R⁴⁰²~R⁴⁰⁴為氫原子、烷基、鹵原子、鹵化烷基、羰基、氰基、胺基、芳硫 基，n^b1為0~5之整數，但至少一個n^b1為1。n^b2~n^b4為0以上之整數]。

[In the formula, R ⁴⁰¹ is a hydrocarbon group that may have substituents, R ⁴⁰² ~ R ⁴⁰⁴ are hydrogen atoms, alkyl groups, halogen atoms, halogenated alkyl groups, carbonyl groups, cyano groups, amino groups, arylthio groups, and n ^b1 is 0~ An integer of 5, but at least one n ^b1 is 1. n ^b2 ~ n ^b4 are integers above 0].

In the general formula (b1-1-1-1) or (b1-1-1-2), R ⁴⁰¹ is a hydrocarbon group which may have substituents, and R ⁴⁰² ~ R ⁴⁰⁴ are hydrogen atoms, alkyl groups, halogen atoms, alkyl halides Group, carbonyl, cyano, amino, aryl, arylthio. n ^b1 is an integer from 0 to 5, but at least one n ^b1 is 1. n ^b2 ~ n ^b4 are integers above 0.

In the general formula (b1-1-1-1) or (b1-1-1-2), the substituted hydrocarbon group of R ⁴⁰¹ is preferably an alkyl group, and a linear or branched alkyl group Preferably, it is a linear alkyl group. The carbon number of the alkyl group is preferably 1-20, more preferably 1-10, particularly preferably 1-6.

R ⁴⁰¹ is also a group represented by -CH ₂ -C(=O)-OR ⁵⁰¹ (R ⁵⁰¹ is a linear or branched alkyl group which may have a substituent, or a cyclic group which may have a substituent).

The linear or branched alkyl group of R ^{501 is the same as} the linear or branched alkyl group described in the aforementioned R ⁴⁰¹ .

The cyclic group of R ^{501 is} , for example, the monocyclic alkane listed in the divalent aliphatic hydrocarbon group in Va ¹ of the general formula (a1-1) described later, or the group obtained by removing one hydrogen atom from the monocyclic alkane, preferably Diamond base, norbornene base.

In addition, R ⁴⁰¹ may be -CH ₂ -OR ⁵⁰² (R ⁵⁰² is a cyclic group). The cyclic base of R ^{502 is} , for example, adamantyl or norbornyl.

In the general formula (b1-1-1-1) or (b1-1-1-2), R ⁴⁰² to R ^{404 are} preferably alkyl groups, and more preferably linear alkyl groups. The number of carbon atoms in the alkyl group is Preferably it is 1-10, more preferably it is 1-5.

In general formula (b1-1-1-1) or (b1-1-1-2), n ^b1 to n ^{b2 are} preferably 1 to 2, and n ^b3 to n ^{b4 are} preferably 0.

In general formula (b1-1-1-1) or (b1-1-1-2), the plural R ⁴⁰¹ can be the same or different, n ^b1 is an integer from 0 to 5, and at least one of the plural n ^b1 is n ^b1 is 1.

Specific examples of preferable cations represented by general formula (b1-1-1) are the cations represented by each of the following.

[式中，g1、g2、g3表示重覆之數，g1為1~5之整數，g2為0~20之整數，g3為0~20之整數]。

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

[式中，R”²⁰¹為氫原子或取代基，取代基如，與前述R¹¹~R¹⁵及R²⁰~R²¹所列舉的作為可具有取代基用之物相同之物]。

[In the formula, R" ²⁰¹ is a hydrogen atom or a substituent, and the substituents are the same as those exemplified for R ¹¹ to R ¹⁵ and R ²⁰ to R ²¹ that may have substituents].

[Compound (b1)]

<Anion Department>

The anion part of (b1) is not particularly limited, but is preferably an anion part represented by the following general formula (b-1).

[式中，R¹⁰¹為可具有取代基之鏈狀烷基，或可具有取代基之鏈狀鏈烯基。R¹⁰²為氟原子或碳數1~5之氟化烷基。Y¹⁰¹為單鍵或含有氧原子之二價連結基。V¹⁰¹為單鍵、伸 烷基、或氟化伸烷基]。

[In the formula, R ¹⁰¹ is a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. R ¹⁰² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ¹⁰¹ is a single bond, alkylene, or fluorinated alkylene].

In formula (b-1), R ¹⁰¹ is an optionally substituted chain alkyl group or an optionally substituted chain alkenyl group.

(Chain alkyl group which may have substituents in R ¹⁰¹ )

The chain alkyl group of R ¹⁰¹ may be linear or branched.

The linear alkyl group preferably has 1-20 carbon atoms, more preferably 1-15, most preferably 1-10. Specifically, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, isotridecyl Alkyl, tetradecyl, pentadecyl, hexadecyl, isohexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, behenyl, Behenyl and so on.

The branched alkyl group preferably has a carbon number of 3-20, more preferably 3-15, most preferably 3-10. For example, 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl Group, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, etc.

(Chain alkenyl group which may have substituents in R ¹⁰¹ )

The chain alkenyl group of R ¹⁰¹ may be linear or branched, and preferably has a carbon number of 2-10, preferably 2-5, more preferably 2-4, particularly preferably 3. Linear alkenyl groups include vinyl, propenyl (allyl), butenyl and the like. Examples of branched alkenyl groups include 1-methpropenyl and 2-methpropenyl.

Among the above-mentioned chain alkenyl groups, a propenyl group is particularly preferred.

The substituents in the chain alkyl or alkenyl group of R ^{101 are} , for example, alkoxy, halogen atom, halogenated alkyl group, hydroxyl group, carbonyl group, nitro group, amine group, and the cyclic formula of R ²¹ in formula (b2) described later Base etc.

In the formula (b-1), Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom.

When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, the Y ¹⁰¹ may contain atoms other than the oxygen atom. Atoms other than oxygen atoms such as carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms, etc.

Divalent linking groups containing oxygen atoms such as oxygen atom (ether bond: -O-), ester bond (-C(=O)-O-), oxycarbonyl group (-OC(=O)-), amide bond (-C(=O)-NH-), carbonyl group (-C(=O)-), carbonate bond (-OC(=O)-O-) and other non-hydrocarbon-containing oxygen atom linking groups; Hydrocarbon series containing oxygen atom linking group and alkylene composition, etc. The composition can be further linked to sulfonyl (-SO ₂ -). For this composition, the linking group represented by each of the following formulas (y-al-1) to (y-al-7).

[式中，V’¹⁰¹為單鍵或碳數1~5之伸烷基，V’¹⁰²為碳數 1~30之二價飽和烴基]。

[In the formula, ^V'101 is a single bond or an alkylene group with 1 to 5 carbons, and ^V'102 is a divalent saturated hydrocarbon group with 1 to 30 carbons].

V ^'102 of the divalent saturated hydrocarbon group is preferably an alkylene group having a carbon number of 1 to 30.

V ^'101 and V' is an alkylene group ¹⁰² may be a linear stretching of the alkyl group or branched alkyl group, preferably straight chain alkylene of.

V ^'101 and V' is an alkylene group specific example ^102, extending methyl _{[-CH 2 -]; - CH} (CH 3) -, - CH (CH 2 CH 3) -, - C (CH 3) 2 -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ -and other alkylene groups; Ethyl [-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 )CH ₂ -and other alkyl ethylene; trimethyl (n- propylene) [-CH ₂ CH ₂ CH ₂ -]; -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ -and other alkyltrimethylene; tetramethylene [-CH ₂ CH ₂ CH ₂ CH ₂ -]; -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -and other alkyltetramethylene; pentamethyl [-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -] and so on.

And, V ^'101 or V' ¹⁰² portion of the alkylene group may be substituted extending from 5 to 10 carbon atoms of the divalent aliphatic cyclic group. The aliphatic cyclic group is preferably a divalent group obtained by removing one hydrogen atom from the cyclic aliphatic hydrocarbon group of Ra' ³ in the formula (a1-r-1) described later, more preferably cyclohexylene, 1 , 5- King Kong base or 2,6- King Kong base.

Y ^{101 is} preferably a divalent linking group containing an ester bond or an ether bond, and preferably a linking group represented by each of the above formulas (y-al-1) to (y-al-5).

In formula (b-1), V ¹⁰¹ is a single bond, an alkylene group or a fluorinated alkylene group. The alkylene group and fluorinated alkylene group of V ¹⁰¹ preferably have 1 to 4 carbon atoms. Fluorinated alkyl groups such as stretch of V ^101, V ¹⁰¹ of the alkylene part or all of the hydrogen atoms are substituted with a fluorine atom. Among them, V ^{101 is} preferably a single bond or a fluorinated alkylene group with 1 to 4 carbon atoms.

In the formula (b-1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms. R ^{102 is} preferably a fluorine atom or a perfluoroalkyl group with 1 to 5 carbon atoms, more preferably a fluorine atom.

Specific examples of the anion portion of the compound (b1) are fluorinated alkylsulfonate anions such as trifluoromethanesulfonate anion or perfluorobutanesulfonate anion when Y ¹⁰¹ is a single bond; Y ¹⁰¹ is oxygen-containing In the case of a divalent linking group of atoms, for example, an anion represented by either of the following formulas (an-1) or (an-3).

[式中，R”¹⁰¹為可具有取代基之鏈狀烷基；R”¹⁰³為可具有取代基之鏈狀鏈烯基；V”¹⁰¹為氟化伸烷基；L”¹⁰¹為-C(=O)-或-SO₂-；v”為各自獨立的0~3之整數，q”為各自獨立的1~20之整數，n”為0或1]。

[In the formula, R” ¹⁰¹ is a chain alkyl group which may have substituents; R” ¹⁰³ is a chain alkenyl group which may have substituents; V” ¹⁰¹ is a fluorinated alkylene group; L” ¹⁰¹ is -C( =O)-or -SO ₂ -; v" is an independent integer of 0 to 3, q" is an independent integer of 1 to 20, n" is 0 or 1].

The chain alkyl group which may have a substituent in R" ¹⁰¹ is preferably the group exemplified in the above-mentioned chain alkyl group in R ^{101. The} chain alkenyl group which may have a substituent in R" ¹⁰³ is preferably, the aforementioned R ¹⁰¹ Medium chain alkenyl groups exemplified. V" ^{101 is} preferably a fluorinated alkylene group having 1 to 3 carbon atoms, particularly preferably -CF ₂ -, -CF ₂ CF ₂ -, -CHFCF ₂ -, -CF(CF ₃ )CF ₂ -, -CH (CF ₃ )CF ₂ -.

In the present invention, the anion part and the cation part of the compound (b1) can be combined arbitrarily with those shown above.

The compound (b1) in the present invention is preferably a compound represented by the following general formula (b1-1).

[式中，R¹¹~R¹³表示各自獨立的可具有取代基之芳基、烷基或鏈烯基。但R¹¹~R¹³中至少一個為含有醚基。R¹¹~R¹³可相互鍵結與式中之硫原子形成環；R⁴¹為鏈狀之氟化烷基]。

[In the formula, R ¹¹ to R ¹³ represent an aryl group, an alkyl group, or an alkenyl group that may have a substituent. However, at least one of R ¹¹ to R ¹³ contains an ether group. R ¹¹ ~ R ¹³ can be bonded to each other to form a ring with the sulfur atom in the formula; R ⁴¹ is a chain fluorinated alkyl].

In the general formula (b1-1), R ¹¹ to R ¹³ represent an aryl, alkyl, or alkenyl group that may have a substituent, respectively, and R ¹¹ to R ^{13 are the} same as described above. R ⁴¹ is a chain fluorinated alkyl group, preferably a fluorinated alkyl group having 1 to 10 carbons, and more preferably a fluorinated alkyl group having 1 to 5 carbons.

[Compound (b2)]

The acid generator containing the photoresist composition in the present invention contains the compound (b2) represented by the following general formula (b2).

[式中，R²¹為可具有取代基之環式基；R²²為氟原子或碳數1~5之氟化烷基；Y²¹為單鍵或含有氧原子之二價連結基；V²¹為單鍵、伸烷基、或氟化伸烷基；M’^m+為m價之有機陽離子]。

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ Is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence].

[Compound (b2)]

<Anion Department>

In general formula (b2), R ²¹ is a cyclic group which may have a substituent.

(Cyclic group that may have substituents in R ²¹ )

The aforementioned cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group.

The aromatic hydrocarbon group of R ^{21 is} , for example, the aromatic hydrocarbon ring listed in the divalent aromatic hydrocarbon group in Va ¹ of the general formula (a1-1) below, or the aromatic compound containing two or more aromatic rings removes one hydrogen atom The resulting aryl group is preferably phenyl or naphthyl.

The cyclic aliphatic hydrocarbon group of R ^{21 is} , for example, a group obtained by removing one hydrogen atom from the divalent aliphatic hydrocarbon group listed in Va ¹ of the general formula (a1-1) described below, preferably For the diamond base, norbornene base.

In addition, the cyclic hydrocarbon group of R ²¹ may contain heteroatoms such as heterocycles, and is specifically as the lactone-containing cyclic group represented by each of the general formulas (a2-r-1) to (a2-r-7) described below, The following general formulas (a5-r-1)~(a5-r-4) each represent the -SO ₂ --containing cyclic group, the others are as follows (r-hr-1)~(r-hr-16) Enumerated heterocyclic groups.

Examples of substituents of the cyclic hydrocarbon group of R ²¹ include alkyl groups, alkoxy groups, halogen atoms, halogenated alkyl groups, hydroxyl groups, carbonyl groups, nitro groups and the like.

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

The alkoxy group used as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, The tert-butoxy group is preferably methoxy and ethoxy.

The halogen atom used as the substituent includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., preferably a fluorine atom.

The halogenated alkyl group used as a substituent is, for example, an alkyl group having 1 to 5 carbon atoms, such as Such as methyl, ethyl, propyl, n-butyl, tert-butyl and other groups in which part or all of the hydrogen atoms are replaced by the aforementioned halogen atoms.

R ^{21 is more} preferably a cyclic hydrocarbon group which may have a substituent. More specifically, phenyl and naphthyl are groups obtained by removing more than one hydrogen atom from a polycyclic alkane. The following general formulas (a2-r-1) to (a2-r-7) each contain lactones The cyclic group of the following general formulas (a5-r-1) to (a5-r-4) each represent -SO ₂ --containing cyclic group, etc.

In general formula (b2), Y ²¹ is a single bond or a divalent linking group containing an oxygen atom. The description of Y ^{21 is the same as} the description of the single bond of Y ¹⁰¹ or the divalent linking group containing an oxygen atom in the aforementioned formula (b-1).

In general formula (b2), V ²¹ is a single bond, an alkylene group, or a halogenated alkylene group.

The description of V ^{21 is} the same as the description of V ^{101 in} the aforementioned general formula (b-1).

In general formula (b2), R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms. R ^{22 is} preferably a fluorine atom or a C1-C5 perfluoroalkyl group, more preferably a fluorine atom.

(b2) Specific examples of the anion portion of the component, when Y ²¹ is a single bond, such as fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anion or perfluorobutanesulfonate anion; Y ²¹ is oxygen-containing In the case of a divalent linking group of atoms, for example, an anion represented by any of the following formulas (an-1) to (an-3).

[式中，R”¹⁰¹為可具有取代基之脂肪族環式基，前述式(r-hr-1)~(r-hr-6)各自所表示之基；R”¹⁰²為可具有取代基之脂肪族環式基，後述一般式(a2-r-1)~(a2-r-7)各自所表示之含有內酯之環式基，或後述一般式(a5-r-1)~(a5-r-4)所表示之含有-SO₂-之環式基；R”¹⁰³為可具有取代基之芳香族環式基，可具有取代基之脂肪族環式基；V”¹⁰¹為氟化伸烷基；L”¹⁰¹為-C(=O)-或-SO₂-；v”各自獨立的0~3之整數，q”為各自獨立的1~20之整數，n”為0或1]。

[In the formula, R” ¹⁰¹ is an aliphatic cyclic group that may have a substituent, and the aforementioned formulas (r-hr-1) to (r-hr-6) each represent a group; R” ¹⁰² is an aliphatic cyclic group that may have a substituent The aliphatic cyclic group, the following general formula (a2-r-1) ~ (a2-r-7) each represented by the lactone-containing cyclic group, or the following general formula (a5-r-1) ~ ( a5-r-4) represents a cyclic group containing -SO ₂ -; R" ¹⁰³ is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent; V" ¹⁰¹ is a fluorine Alkylene; L" ¹⁰¹ is -C(=O)- or -SO ₂ -; v" is an independent integer of 0 to 3, q" is an independent integer of 1 to 20, n" is 0 or 1].

The aliphatic cyclic group which may have a substituent in R" ¹⁰¹ , R " ¹⁰² and R" ¹⁰³ is preferably the group exemplified by the cyclic aliphatic hydrocarbon group in the aforementioned R ^{21. The} aforementioned substituents are, for example, and substitutable R The substituents of the cyclic aliphatic hydrocarbon group in ²¹ are the same.

The aromatic cyclic group which may have a substituent in R" ¹⁰³ is preferably the group exemplified in the aromatic hydrocarbon group in the cyclic hydrocarbon group of R ^21. The substituent is for example, and the aromatic hydrocarbon group that may be substituted for R ²¹ Substituents are the same.

The specific example of the anion part of compound (b2) is shown below.

[Compound (b2)]

<Cation part>

In the formula (b2), M'm ⁺ is an organic cation with m valence, among which a cation or iodonium cation is preferred, and the cations represented by the following general formulas (ca-1)~(ca-4) are particularly preferred .

[式中，R²⁰¹~R²⁰⁷及R²¹¹~R²¹²表示各自獨立的可具有取代基之芳基、烷基或鏈烯基，R²⁰¹~R²⁰³、R²⁰⁶~R²⁰⁷、R²¹¹~R²¹²可相互鍵結與式中之硫原子形成環。R²⁰⁸~R²⁰⁹ 表示各自獨立的氫原子或碳數1~5之烷基，R²¹⁰為可具有取代基之芳基、烷基、鏈烯基，或含有-SO₂-之環式基，L²⁰¹表示-C(=O)-或-C(=O)-O-，Y²⁰¹表示各自獨立的伸芳基、伸烷基或伸鏈烯基，x為1或2，W²⁰¹表示(x+1)價之連結基。

[In the formula, R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² represent independent aryl, alkyl or alkenyl groups which may have substituents, R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , R ²¹¹ to R ²¹² can bond with each other to form a ring with the sulfur atom in the formula. R ²⁰⁸ to R ²⁰⁹ represent independent hydrogen atoms or alkyl groups with 1 to 5 carbon atoms, R ²¹⁰ represents optionally substituted aryl, alkyl, alkenyl, or cyclic groups containing -SO ₂ -, L ²⁰¹ represents -C(=O)- or -C(=O)-O-, Y ²⁰¹ represents independent aryl, alkylene or alkenylene, x is 1 or 2, W ²⁰¹ represents ( x+1) The link base of the price.

The aryl groups of R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ^{212 are} , for example, unsubstituted aryl groups with 6 to 20 carbon atoms, preferably phenyl and naphthyl.

The alkyl groups of R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² may be chain or cyclic alkyl groups, preferably having 1 to 30 carbon atoms.

The alkenyl groups of R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² preferably have 2 to 10 carbon atoms.

R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have substituents such as alkyl, halogen, halogenated alkyl, carbonyl, cyano, amino, aryl, arylthio, the following formula (ca-r -1)~(ca-r-7) each represents the base.

The aryl group in the arylthio group used as the substituent is the same as those exemplified for R ²¹ , and specific examples are phenylthio or biphenylthio.

[式中，R’²⁰¹為各自獨立的氫原子，可具有取代基之環式基、鏈狀烷基或鏈狀鏈烯基]。

[In the formula, ^R'201 is each independent hydrogen atom, which may have a cyclic group, a chain alkyl group or a chain alkenyl group which may have a substituent].

R ^'201 may be the group having a cyclic substituent, the alkyl group may have a substituent group of the chain, or an alkenyl group such as a chain, and (b-1) in the above formula R ¹⁰¹ substituents of the The same thing as R ²¹ in the formula (b2), but a cyclic group which may have a substituent or a chain alkyl group which may have a substituent, for example, with the acid dissociation represented by the following general formula (a1-r-2) Based on the same thing.

When R ²⁰¹ ~R ²⁰³ , R ²⁰⁶ ~R ²⁰⁷ , R ²¹¹ ~R ²¹² are linked to each other to form a ring with the sulfur atom in the formula, heteroatoms such as sulfur, oxygen, nitrogen, etc. may be interposed, or a carbonyl group,- SO-, -SO ₂ -, -SO ₃ -, -COO-, -CONH- or -N(R _N )- (the _RN is an alkyl group with 1 to 5 carbon atoms) and other functional groups are bonded. The ring formed is a ring in which the ring skeleton contains a sulfur atom in the formula, preferably a 3-10 membered ring containing a sulfur atom, and particularly preferably a 5-7 membered ring. Specific examples of the formed ring include a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a phenothioxan ring, and a tetrahydrothiophenium ring , Tetrahydrothiopyrylium ring, etc.

R ²⁰⁸ to R ²⁰⁹ represent a hydrogen atom or an alkyl group with 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group with 1 to 3 carbon atoms, which can be linked to each other to form a ring when they are alkyl groups.

R ²¹⁰ is 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 cyclic group containing -SO ₂ -which may have a substituent.

The aryl group of R ²¹⁰ is an unsubstituted aryl group having 6 to 20 carbon atoms, preferably phenyl and naphthyl.

The alkyl group of R ²¹⁰ may be a chain or cyclic alkyl group, and preferably has a carbon number of 1-30.

The alkenyl group of R ²¹⁰ preferably has 2 to 10 carbon atoms.

The cyclic group containing -SO ₂ -that may have a substituent of R ^{210 is} , for example, the same as the "cyclic group containing -SO ₂ -" of Ra ^{21 in} the general formula (a2-1) described below, preferably The group represented by the general formula (a5-r-1) will be described later.

Y ²⁰¹ represents an aryl, alkylene or alkenylene group independently of each other.

The aryl group of Y ^{201 is} , for example, a group obtained by removing one hydrogen atom from the aryl group exemplified by the aromatic hydrocarbon group of R ^{21 in} the above formula (b2).

The alkylene and alkenylene of Y ^{201 are} , for example, the same as the aliphatic hydrocarbon group used as the divalent hydrocarbon group of Va ^{1 in} the general formula (a1-1) described later.

In the aforementioned formula (ca-4), x is 1 or 2.

W ²⁰¹ is (x+1) valence, that is, the linking base of divalent or trivalent.

The divalent linking group of W ²⁰¹ is preferably a divalent hydrocarbon group which may have a substituent, for example, the same hydrocarbon group as Ya ^{21 of the} general formula (a2-1) described later. The divalent linking group of W ²⁰¹ may be any of linear, branched or cyclic, and is preferably cyclic. Among them, a group obtained by combining two carbonyl groups at both ends of an aryl group is preferred. Arylene groups such as phenylene and naphthylene are particularly preferred as phenylene.

The trivalent linking group of W ^{201 is} , for example, a group obtained by removing one hydrogen atom from the divalent linking group of W ²⁰¹ , and a group obtained by bonding the aforementioned divalent linking group to the aforementioned divalent linking group. The trivalent linking group of W ²⁰¹ is preferably a group obtained by bonding an aryl group to two carbonyl groups.

Specific examples of preferable cations represented by formula (ca-1) are cations represented by the following formulas (ca-1-1) to (ca-1-63).

[式中，g1、g2、g3表示重覆數，g1為1~5之整數，g2為0~20之整數，g3為0~20之整數]。

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

[式中，R”²⁰¹為氫原子或取代基，取代基為與前述R²⁰¹~R²⁰⁷及R²¹⁰~R²¹²可具有之取代基所列舉之物相同]。

[In the formula, R" ²⁰¹ is a hydrogen atom or a substituent, and the substituents are the same as those exemplified for the substituents that may be possessed by R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² ].

The specific example of a cation preferably represented by the aforementioned formula (ca-3) is a cation represented by each of the following formulas (ca-3-1) to (ca-3-6).

Specific examples of preferable cations represented by the aforementioned formula (ca-4) are cations represented by the following formulas (ca-4-1) to (ca-4-2).

[Compound (b3)]

In the present invention, the component (B) preferably contains a compound (b3) having a bisazomethylene disulfonic acid skeleton. The compound (b3) is, for example, diazolidene disulfonic acid bicyclohexane.

(B) The addition ratio of compound (b1) to compound (b2) in component (b1) is preferably 1.0 to 2.0 parts by mass of compound (b2) relative to 1 part by mass of compound (b1), more preferably 1.2 to 1.7 parts by mass Parts, particularly preferably 1.2 to 1.5 parts by mass.

When the addition ratio is in the above range, a thing with a good photoresist pattern shape can be obtained.

In the photoresist composition of the present invention, the content of the component (B) relative to 100 parts by weight of the component (A) is preferably 0.5-60 parts by mass, preferably 1-50 parts by mass, more preferably 1-40 parts by mass Copies. (B) When the content of the component is in the above range, the pattern can be sufficiently formed. In addition, when the components of the photoresist composition are dissolved in an organic solvent, a uniform solution can be obtained and good storage safety is preferable.

<Resin component: (A) component>

The photoresist composition of the present invention preferably contains at least one resin selected from the group consisting of novolac resin, polyhydroxystyrene resin and acrylic resin.

[Novolac resin]

The novolak resin is not particularly limited, and can be arbitrarily selected from those previously proposed as commonly used photoresist compositions, and is preferably a novolak resin obtained by the condensation reaction of an aromatic hydroxy compound with aldehydes and/or ketones.

Aromatic hydroxyl compounds used in the synthesis of novolac resins such as phenol; m-cresol, p-cresol, o-cresol and other cresols; 2,3-xylenol, 2,5-xylenol, Xylenols such as 3,5-xylenol and 3,4-xylenol; m-ethylphenol, p-ethylphenol, o-ethylphenol, 2,3,5-trimethylphenol , 2,3,5-triethylphenol, 4-tert-butylphenol, 3-tert-butylphenol, 2-tert-butylphenol, 2-tert-butyl-4-methylphenol, 2 -tert-butyl-5-methylphenol and other alkylphenols; p-methoxyphenol, m-methoxyphenol, p-ethoxyphenol, m-ethoxyphenol, p-propoxy Alkoxyphenols such as methyl phenol and m-propoxyphenol; o-isopropenyl phenol, p-isopropenyl phenol, 2-methyl-4-isopropenyl phenol, 2-ethyl-4- Isopropenyl phenols such as isopropenyl phenol; aryl phenols such as phenylphenol; 4,4'-dihydroxybiphenyl, bisphenol A, resorcinol, hydroquinone, caramel phenol, etc. Hydroxyphenols, etc. These can be used alone or in combination of two or more kinds.

Aldehydes for the synthesis of novolac resins such as formaldehyde, p-formaldehyde, trioxane, acetaldehyde, propionaldehyde, butyraldehyde, trimethylacetaldehyde, acrolein, crotonaldehyde, cyclohexanal, furfural, furan propylene Aldehydes, benzaldehyde, terephthalaldehyde, phenylacetaldehyde, α -phenylpropionaldehyde, β-phenylpropionaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-formaldehyde Base benzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, cinnamic acid aldehyde, etc. These can be used alone or in combination of two or more kinds.

Among these aldehydes, it is preferable to use formaldehyde for easy availability. To obtain good heat resistance, it is particularly preferable to use formaldehyde in combination with hydroxybenzaldehydes such as o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, and p-hydroxybenzaldehyde.

The ketones used in the synthesis of novolac resins include acetone, methyl ethyl ketone, diethyl ketone, and diphenyl ketone. These can be used alone or in combination of two or more kinds.

In addition, the above-mentioned aldehydes and ketones can be used in combination. The novolak resin can be obtained by condensation reaction of the aforementioned aromatic hydroxy compound with aldehydes and/or ketones by a known method in the presence of an acidic catalyst. The acid catalyst used at this time can be hydrochloric acid, sulfuric acid, formic acid, oxalic acid, p-toluenesulfonic acid, etc.

The mass average molecular weight (Mw) of the novolak resin (calculated by gel permeation chromatography (GPC) polystyrene), that is, the Mw of component (A) before being protected by an acid dissociable dissolution inhibitor is preferably 2000 to 50000 Within the range, 3000~20000 is better, more preferably 4000~15000. When the Mw is more than 2000, the negative photoresist composition can be dissolved in an organic solvent and then coated on the substrate to obtain good coating properties, and more than 50,000 Good resolution can be obtained when down.

In the present invention, the novolak resin preferably implements the removal of low molecular weight substances. This can further improve heat resistance.

In addition, the low-molecular-weight system in this specification includes, for example, monomers such as aromatic hydroxy compounds, aldehydes, ketones, etc. used in the synthesis of novolac resins, unreacted monomers, and monomers bonded by two molecules of this monomer. Dimers obtained by bonding, trimers obtained by bonding three molecules, etc. (monomers and di-trinuclear bodies, etc.).

There are no particular limitations on the method of separate treatment of low-molecular-weight substances. For example, a method of purification using an ion exchange resin, and a known separate operation using a good solvent (alcohol, etc.) and a weak solvent (water, etc.) of the resin. With the aforementioned method, low molecular weight substances, acid components, and metal components can be simultaneously removed.

The respective removal treatment of such low molecular weight substances is preferably such that the yield is in the range of 50 to 95% by mass.

At 50% by mass or more, the difference in the dissolution rate between the exposed part and the unexposed part can be increased, resulting in good resolution. In addition, at 95 mass% or less, sufficient effects of separate removal can be obtained.

In addition, the content of the low molecular weight substance with an Mw of 500 or less is preferably 15% or more on the GPC chart, and more preferably 12% or less. By making it less than 15%, the effect of improving the heat resistance of the photoresist pattern can be achieved at the same time, and the output of sublimation during the heat treatment can be suppressed.

[Polyhydroxystyrene resin]

Polyhydroxystyrene resin is also used with hydroxystyrene derived The constitutional unit resin (hereinafter referred to as polyhydroxystyrene (PHS) resin) is preferred. By using this type of resin, high-resolution patterns can be formed.

In addition, even a thick film can be finely processed, so a pattern with a high aspect ratio can be formed, and as a result, resistance to dry etching can be improved.

At this time, "hydroxystyrene" refers to hydroxystyrene, and the hydrogen atom bonded to the carbon atom at the α -position of hydroxystyrene is substituted with other substituents such as halogen atoms, alkyl groups, and halogenated alkyl groups. And the concept of these derivatives (preferably those with the above-mentioned substituents bonded to the benzene ring). The number of hydroxyl groups bonded to the benzene ring of hydroxystyrene is preferably an integer of 1 to 3, more preferably 1. In addition, the α -position (carbon atom at the α -position) of hydroxystyrene refers to the carbon atom bonded to the benzene ring, unless otherwise specified.

"Constituent unit derived from hydroxystyrene" refers to a constituent unit formed by cracking of the ethylenic double bond of hydroxystyrene.

The ratio of the structural units derived from hydroxystyrene in the PHS-based resin is preferably 50-100 mol%, and more preferably 80-100 mol% relative to the total of all the structural units constituting the PHS-based resin. Specific examples of PHS-based resins include polyhydroxystyrene, hydroxystyrene-styrene copolymer, and the like.

The hydroxystyrene-styrene copolymer is, for example, a copolymer having a structural unit (ps1) represented by the following general formula (I) and a structural unit (ps2) represented by the following general formula (II).

(式中，R^st表示氫原子或甲基，m₀₁表示1~3之整數)。

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

(式中，R^st表示氫原子或甲基，R⁰¹表示碳數1~5之烷基，m₀₂表示0或1~3之整數)。

(In the formula, R ^st represents a hydrogen atom or a methyl group, R ⁰¹ represents an alkyl group with a carbon number of 1 to 5, and m ₀₂ represents an integer of 0 or 1 to 3).

In the structural unit (ps1) represented by the above general formula (I), R ^st is a hydrogen atom or a methyl group, and preferably a hydrogen atom.

m ₀₁ is an integer from 1 to 3. Wherein m _{01 is} preferably 1.

The position of the hydroxyl group may be any of o-position, m-position, and p-position, but from the viewpoint of easy availability and low price, it is preferably a product where m is 1 and the p-position has a hydroxyl group. When m ₀₁ is 2 or 3, any substitution positions can be combined.

In the structural unit (ps2) represented by the above general formula (II), R ^st is a hydrogen atom or a methyl group, and preferably a hydrogen atom.

The above R ⁰¹ is a linear or branched alkyl group with 1 to 5 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, Isopentyl, neopentyl, etc. Industrially, it is preferably methyl or ethyl.

The above m ₀₂ is 0 or an integer of 1~3. Among them, m _{02 is} preferably 0 or 1, and 0 is particularly preferred in industry.

In addition, when m ₀₂ is 1, the substitution position of R1 can be any of o-position, m-position, and p-position, and when m ₀₂ is 2 or 3, any substitution positions can be combined.

In addition, PHS-based resins can use 3-40 mol% of the hydrogen atoms in the hydroxyl groups of polyhydroxystyrene to be replaced by alkali-insoluble groups to reduce alkali-soluble substances.

In addition, PHS-based resins can be used in copolymers with the aforementioned structural unit (ps1) and structural unit (ps2). In the hydroxyl group of the structural unit (ps1), 5-30 mol% of the hydrogen atoms are replaced by alkali-insoluble groups to reduce Alkali soluble matter.

In this case, the "alkali-insoluble group" refers to a substituent that can reduce the alkali solubility of the unsubstituted alkali-soluble resin, such as tert-butoxycarbonyl, tert-pentoxycarbonyl and other tertiary alkoxycarbonyl groups, methyl Lower alkyl groups such as propyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, etc.

The mass average molecular weight of the PHS resin is preferably 1,000 to 10,000, especially when KrF excimer lasers and/or electron beams are used for mixing and blending, and more preferably 2,000 to 4,000.

[Acrylic]

The acrylic resin preferably has a structural unit (a1) containing an acid-decomposable group that increases polarity by the action of an acid, and contains a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO _2- The constituent unit (a2) of the cyclic group (except those equivalent to the aforementioned constituent unit (a1)), and the constituent unit (a3) containing an aliphatic hydrocarbon group containing a polar group (but equivalent to the aforementioned constituent unit (a1), (a2) except), and the structural unit (a4) containing acid non-dissociable cyclic group.

It is also possible to use a resin containing the structural unit (a1) represented by the following general formulas (a1-1) to (a1-2).

[式中，R為氫原子，碳數1~5之烷基或碳數1~5之鹵化烷基。Va¹為可具有醚鍵、脂基甲酸酯鍵或醯胺鍵之二價烴基，n_a1為各自獨立的0~2，Ra¹為下述式(a1-r-1)~(a1-r-2)所表示之酸解離性基。Wa¹為n_a2+1價之烴基，n_a2為1~3，Ra²為下述式(a1-r-1)或(a1-r-3)所表示之酸解離性基]。

[In the formula, R is a hydrogen atom, an alkyl group with 1 to 5 carbons or a halogenated alkyl group with 1 to 5 carbons. Va ¹ is a divalent hydrocarbon group that may have an ether bond, aliphatic ester bond or an amide bond, n _a1 is independently 0~2, and Ra ¹ is the following formula (a1-r-1)~(a1- r-2) The acid dissociable group represented by. Wa ¹ is a hydrocarbon group having _na2 +1 valence, _na2 is 1 to 3, and Ra ² is an acid dissociable group represented by the following formula (a1-r-1) or (a1-r-3)].

In the aforementioned formula (a1-1), the alkyl group having 1 to 5 carbon atoms is preferably linear or branched, specifically, for example, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl Base, tert-butyl, pentyl, isopentyl, neopentyl, etc. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms in the alkyl group having 1 to 5 carbon atoms are substituted by halogen atoms. The halogen atom such as fluorine atom, chlorine Atom, bromine atom, iodine atom, etc., particularly preferably fluorine atom.

R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, and is industrially easily available, and hydrogen atom or methyl is most preferred.

The divalent hydrocarbon group of Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group refers to a hydrocarbon group that does not possess aromaticity. The aliphatic hydrocarbon group used as the divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and saturated is generally preferred.

The aforementioned aliphatic hydrocarbon group is more specifically, for example, a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group containing a ring in the structure.

In addition, Va ¹ is a product obtained by bonding an ether bond, a urethane chain, or an amide chain through the above-mentioned divalent hydrocarbon group.

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

The linear aliphatic hydrocarbon group is preferably a linear alkylene group, for example, methylidene [-CH ₂ -], ethylidene [-(CH ₂ ) ₂ -], trimethylene [- (CH ₂ ) ₃ -], tetramethylene [-(CH ₂ ) ₄ -], pentamethylene [-(CH ₂ ) ₅ -], etc.

The branched aliphatic hydrocarbon group is preferably a branched alkylene group, specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C (CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ -and other alkylene groups; -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 -and other alkylene groups; -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ -and other alkyl groups; -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH ₂ -such as alkyl tetramethylene, etc. alkylene, etc. The alkyl group of the alkylene alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

The aliphatic hydrocarbon group containing a ring in the aforementioned structure, such as an alicyclic hydrocarbon group (a group in which two hydrogen atoms are removed from an aliphatic hydrocarbon ring), an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group The obtained group and the alicyclic hydrocarbon group are in the middle of the linear or branched aliphatic hydrocarbon group. The aforementioned linear or branched aliphatic hydrocarbon group is the same as the aforementioned.

The aforementioned alicyclic hydrocarbon group preferably has a carbon number of 3-20, more preferably 3-12.

The aforementioned alicyclic hydrocarbon group may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocyclic alkane. The monocyclic alkane is preferably one having 3 to 6 carbon atoms, such as cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycyclic alkane. The polycyclic alkane is preferably a carbon number of 7-12, such as adamantane, norbornane, Isobornane, tricyclodecane, tetracyclododecane, etc.

The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring.

The aromatic hydrocarbon group used as the divalent hydrocarbon group in the aforementioned Va ¹ preferably has a carbon number of 3 to 30, preferably 5 to 30, more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10 . However, the carbon number does not include the carbon number of the substituent.

Specific examples of aromatic rings possessed by aromatic hydrocarbon groups include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene, etc.; aromatic heterocycles in which part of the carbon atoms constituting the aforementioned aromatic hydrocarbon ring are replaced by heteroatoms, etc. . The heteroatoms of aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms.

The aromatic hydrocarbon group is specifically such as removing two hydrogen atoms from the aforementioned aromatic hydrocarbon ring A group (aryl group) obtained by removing a hydrogen atom from the aforementioned aromatic hydrocarbon ring (aryl group) in which one hydrogen atom is replaced by an alkylene group (for example, benzyl, phenethyl, 1- Naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl and other arylalkyl groups are obtained by removing one hydrogen atom); by containing two or more Aromatic compounds of the aromatic ring (such as biphenyl, fluorene, etc.) are the groups obtained by removing two hydrogen atoms. The number of carbon atoms in the aforementioned alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In the aforementioned formula (a1-2), the hydrocarbon group with valence n _a2 + ¹ in Wa ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group refers to a hydrocarbon group that does not possess aromaticity, and can be saturated or unsaturated, and generally saturated is preferred. The aforementioned aliphatic hydrocarbon groups such as linear or branched aliphatic hydrocarbon groups, aliphatic hydrocarbon groups containing a ring in the structure, or a combination of linear or branched aliphatic hydrocarbon groups and aliphatic hydrocarbon groups containing a ring in the structure Specifically, the base is the same as Va ^{1 in the} above formula (a1-1).

The aforementioned n _a2 +1 valence is preferably 2 to 4 valence, more preferably 2 or 3 valence.

[式中，Ra’¹、Ra’²為氫原子或烷基，Ra’³為烴基，Ra’³可與Ra’¹、Ra’²中任一方鏈結形成環。一般式(a1-r-1)所表示之酸解離性基(以下為了方便稱為「縮醛型酸解離性基」)]。

[In the formula, Ra' ¹ and Ra' ² are hydrogen atoms or alkyl groups, Ra' ³ is a hydrocarbyl group, and Ra' ³ can be linked to either of Ra' ¹ and Ra' ² to form a ring. The acid dissociable group represented by the general formula (a1-r-1) (hereinafter referred to as "acetal-type acid dissociable group" for convenience)].

^'1, Ra', such as an alkyl group of ^2, when the above described α-substituted acrylate may be bonded to a carbon atom of α position of the substituent group include the same things as the formula (a1-r-1) wherein Ra alkyl, Preferably it is methyl or ethyl, most preferably methyl.

The hydrocarbon group of Ra' ³ is preferably an alkyl group having 1 to 20 carbons, more preferably an alkyl group having 1 to 10 carbons; specific examples of linear or branched alkyl groups are preferably such as methyl, ethyl Base, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, 1,1-dimethylethyl, 1,1-diethyl Propyl, 2,2-dimethylpropyl, 2,2-dimethylbutyl, etc.

When Ra' ³ is a cyclic hydrocarbon group, it can be aliphatic or aromatic, and can be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a monocyclic alkane. The monocyclic alkane is preferably one having 3 to 8 carbon atoms, such as cyclopentane, cyclohexane, cyclooctane and the like. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycyclic alkane. The polycyclic alkane is preferably a substance with 7 to 12 carbon atoms, such as adamantane, norbornane, Isobornane, tricyclodecane, tetracyclododecane, etc.

When it is an aromatic hydrocarbon group, the specific aromatic ring contained therein includes aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene, etc.; aromatic hydrocarbon rings in which part of the carbon atoms constituting the aforementioned aromatic hydrocarbon ring are replaced by heteroatoms Group heterocycles and so on. The heteroatoms of aromatic heterocycles are oxygen atoms, sulfur atoms, nitrogen atoms, etc.

The aromatic hydrocarbon group is specifically a group obtained by removing one hydrogen atom from the aforementioned aromatic hydrocarbon ring (aryl group); a group in which one hydrogen atom in the aforementioned aryl group is substituted by an alkylene group (for example, benzyl, phenethyl, 1- Naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl and other arylalkyl groups). The carbon number of the aforementioned alkylene (the alkane chain in the aryl alkyl group) is preferably 1 to 4, more preferably 1~2, particularly preferably 1.

When Ra' ^{3 is} bonded to any one of Ra' ¹ and Ra' ² to form a ring, the cyclic group is preferably a 4-7 membered ring, more preferably a 4-6 membered ring. Specific examples of the cyclic group include tetrahydropyranyl and tetrahydrofuranyl.

The acid dissociable group that protects the carboxyl group in the above polar group is, for example, the acid dissociable group represented by the following general formula (a1-r-2) (the acid represented by the following formula (a1-r-2) Among the dissociable groups, what is composed of an alkyl group is called a "tertiary alkyl ester type acid dissociable group").

[式中，Ra’⁴~Ra’⁶為烴基，Ra’⁵、Ra’⁶可相互鍵結形成環]。

[In the formula, Ra' ⁴ to Ra' ⁶ are hydrocarbon groups, and Ra' ⁵ and Ra' ⁶ can be bonded to each other to form a ring].

The hydrocarbon group of Ra' ⁴ to Ra' ^{6 is} the same as the aforementioned Ra' ³ . Ra' ^{4 is} preferably an alkyl group having 1 to 5 carbon atoms. When Ra' ⁵ and Ra' ⁶ are bonded to each other to form a ring, for example, a group represented by the following general formula (a1-r2-1).

In addition, when Ra' ⁴ to Ra' ^{6 are} not bonded to each other but are independent hydrocarbon groups, for example, a group represented by the following general formula (a1-r2-2).

[式中，Ra’¹⁰為碳數1~10之烷基，Ra’¹¹為與Ra’¹⁰所鍵結之碳原子形成脂肪族環式基之基，Ra’¹²~Ra’¹⁴表示各自獨立之烴基]。

[In the formula, Ra' ¹⁰ is an alkyl group with 1 to 10 carbon atoms, Ra' ¹¹ is a group that forms an aliphatic cyclic group with the carbon atom bonded to Ra' ¹⁰ , and Ra' ¹² to Ra' ¹⁴ are independent The hydrocarbyl].

The alkyl group of the alkyl group having 1 to 10 carbon atoms of Ra' ^{10 in} the formula (a1-r2-1) is preferably the linear or branched alkyl group of Ra' ^{3 in} the formula (a1-r-1) The listed base. The aliphatic cyclic group formed by Ra' ¹¹ in formula (a1-r2-1) is preferably a group exemplified by the cyclic alkyl group of Ra' ³ in formula (a1-r-1).

Of formula (a1-r2-2) wherein Ra 'and ^{12 is} Ra' ¹⁴ each independently preferably an alkyl group having 1 to 10 carbon atoms, the alkyl group which in turn formula (a1-r-1) wherein Ra ^'3 of the straight The groups exemplified for the chain or branched alkyl are preferred, more preferably a linear alkyl having 1 to 5 carbon atoms, and particularly preferably a methyl or ethyl group.

Ra' ¹³ in the formula (a1-r2-2) is preferably a linear, branched or cyclic alkyl group exemplified by the hydrocarbon group of Ra' ^{3 in} the formula (a1-r-1).

Among them, the groups exemplified for the cyclic alkyl group of Ra' ³ are more preferable.

Specific examples of the aforementioned formula (a1-r2-1) are as follows. In the following formula, "*" represents a bonding key.

Specific examples of the aforementioned formula (a1-r2-2) are as follows.

In addition, the acid dissociable group that protects the hydroxyl group in the polar group is, for example, the acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as "tertiary alkoxycarbonyl acid dissociable group" for convenience) ").

[式中，Ra’⁷~Ra’⁹表示烷基]。

[In the formula, Ra' ⁷ to Ra' ⁹ represent an alkyl group].

In the formula (a1-r-3), Ra' ⁷ to Ra' ^{9 are} preferably alkyl groups having 1 to 5 carbon atoms, more preferably 1 to 3.

Furthermore, the total carbon number of each alkyl group is preferably 3-7, more preferably 3-5, most preferably 3-4.

The aforementioned formula (a1-2) is particularly preferably a structural unit represented by the following general formula (a1-2-01).

In the formula (a1-2-01), Ra ² is an acid dissociable group represented by the above 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, more preferably 1. R is the same as before.

The following are specific examples of the aforementioned formula (a1-1). In the following formulae, R ^α is a hydrogen atom, a methyl group or a trifluoromethyl group.

The following are specific examples of the aforementioned formula (a1-2).

The ratio of the constituent unit (a1) in the component (A) relative to all the constituent units constituting the component (A) is preferably 20 to 80 mol%, more preferably 20 to 75 mol%, and more preferably 25 to When 70 mol% is above the lower limit, the lithographic etching characteristics such as sensitivity, resolution, and LWR can be improved. In addition, when it is below the upper limit, it can be balanced with other constituent units.

(Component Unit (a2))

The constituent unit (a2) is a cyclic group containing -SO ₂ -, a cyclic group containing carbonate, or a constituent unit containing a cyclic group containing -SO ₂ -.

The cyclic group containing -SO ₂ -of the constituent unit (a2) is a substance that can effectively improve the adhesion of the photoresist film to the substrate when the component (A) is used when forming the photoresist film.

In the present invention, the component (A) preferably has a structural unit (a2).

In addition, when the aforementioned structural unit (a1) contains a cyclic group containing -SO ₂ -in its structure, the structural unit may correspond to structural unit (a2), but such structural unit corresponds to structural unit (a1) , Does not correspond to the constituent unit (a2).

The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

[式中，R為氫原子、碳數1~5之烷基或碳數1~5之鹵化烷基，Ya²¹為單鍵或二價連結基，La²¹為-O-、-COO-、-CON(R’)-、-OCO-、-CONHCO-或-CONHCS-，R’表示氫原子或甲基。但La²¹為-O-時，Ya²¹不為-CO-。Ra²¹為含有-SO₂-之環式基、含有內酯之環式基或含有碳酸酯之環式基]。

[In the formula, R is a hydrogen atom, an alkyl group with 1 to 5 carbons or a halogenated alkyl group with 1 to 5 carbons, Ya ²¹ is a single bond or a divalent linking group, and La ²¹ is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO- or -CONHCS-, R'represents a hydrogen atom or a methyl group. However, when La ²¹ is -O-, Ya ^{21 is} not -CO-. Ra ²¹ is a cyclic group containing -SO ₂ -, a cyclic group containing a lactone, or a cyclic group containing a carbonate].

The divalent linking group of Ya ²¹ is not particularly limited, and is preferably a divalent hydrocarbon group that may have a substituent, a divalent linking group containing a heteroatom, and the like.

(Divalent hydrocarbon group that may have substituents)

The hydrocarbon group used as the divalent linking group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

The aliphatic hydrocarbon group refers to a hydrocarbon group that does not possess aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and saturated is generally preferred.

Examples of the aforementioned aliphatic hydrocarbon groups include linear or branched aliphatic hydrocarbon groups or aliphatic hydrocarbon groups containing rings in the structure, and specific examples include the groups exemplified by Va ^{1 in} the above formula (a1-1).

The aforementioned 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 by a fluorine atom, and a carbonyl group.

The aliphatic hydrocarbon group containing a ring in the aforementioned structure, such as a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) that may contain a heteroatom-containing substituent in the ring structure, the aforementioned cyclic aliphatic hydrocarbon group A group bonded to the terminal of a linear or branched aliphatic hydrocarbon group, a group in which the aforementioned cyclic aliphatic hydrocarbon group is in the middle of a linear or branched aliphatic hydrocarbon group, etc. The aforementioned linear or branched aliphatic hydrocarbon group is the same as the aforementioned.

The cyclic aliphatic hydrocarbon group preferably has a carbon number of 3-20, more preferably 3-12.

The cyclic aliphatic hydrocarbon group is specifically exemplified by Va ^{1 in} the above formula (a1-1).

The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like.

The aforementioned alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably methyl, ethyl, propyl, n-butyl, tert-butyl.

The aforementioned alkoxy group used as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy , Tert-butoxy, the best is methoxy and ethoxy.

The aforementioned halogen atom used as the substituent includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., preferably a fluorine atom.

The aforementioned halogenated alkyl groups used as substituents are, for example, part of the aforementioned alkyl groups or All hydrogen atoms are substituted by the aforementioned halogen atoms.

The cyclic aliphatic hydrocarbon group may be that part of the carbon atoms constituting the ring structure is substituted by a substituent containing a heteroatom, and the substituent containing a heteroatom is preferably -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O-.

Specific examples of the aromatic hydrocarbon group used as the divalent hydrocarbon group include the groups exemplified by Va ^{1 in} the above formula (a1-1).

The aforementioned aromatic hydrocarbon group may be one in which the hydrogen atom of the aromatic hydrocarbon group is substituted with a substituent. For example, the hydrogen atom to which the aromatic ring is bonded in the aromatic hydrocarbon group may be substituted by a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

The aforementioned alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably methyl, ethyl, propyl, n-butyl, tert-butyl.

The alkoxy group, halogen atom, and halogenated alkyl group used as the aforementioned substituents are exemplified as the substituents used to replace the hydrogen atom of the aforementioned cyclic aliphatic hydrocarbon group.

(Divalent linking group containing heteroatoms)

Heteroatoms in a bivalent linking group containing heteroatoms refer to atoms other than carbon atoms and hydrogen atoms, such as oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms, and the like.

When Ya ²¹ is a divalent linking group containing heteroatoms, the linking group is preferably such as -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O -, -C(=O)-NH-, -NH-, -NH-C(=NH)-(H can be substituted by substituents such as alkyl and acyl), -S-, -S(=O _{) 2 -, - S (=} O) 2 -O-, the general formula ^{-Y 21 -OY 22 -, - Y} 21 -O -, - Y 21 -C (= O) -O -, - C (= O ^{) -O - Y 21, [Y} 21 -C (= O) -O] m '-Y 22 - or ^{-Y 21 -OC (= O) -Y} 22 - represented by the group [wherein, Y ²¹ And Y ²² are each independently a divalent hydrocarbon group that may have a substituent, O is an oxygen atom, and m'is an integer of 0 to 3].

When the aforementioned heteroatom-containing divalent linking group is -C(=O)-NH-, -NH-, -NH-C(=NH)-, the H may be substituted with a substituent such as an alkyl group and an acyl group. The substituent (alkyl group, acyl group) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5.

It is the formula -Y ²¹ -OY ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-OY ²¹ , -[Y ²¹ -C(=O ) -O] _{m '-Y} ²² - or ^{-Y 21 -OC (= O) -Y} 22 - in, Y ²¹ and Y ²² are each independently a divalent hydrocarbon group may have the substituent. The divalent hydrocarbon group is, for example, the same as the "divalent hydrocarbon group which may have a substituent" described in the aforementioned divalent linking group.

Y ^{21 is} preferably a linear aliphatic hydrocarbon group, preferably a linear alkylene group, more preferably a linear alkylene group with 1 to 5 carbon atoms, particularly preferably a methylidene group or an ethylidene group. base.

Y ^{22 is} preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylidene group, an ethylene group or an alkylene group. The alkyl group in the alkyl 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 most preferably a methyl group.

The formula ^{- [Y 21 -C (= O} ) -O] m '-Y 22 - in the group represented, m' is an integer of 0 to 3, again preferably an integer of 0 to 2, more preferably 0 or 1, particularly preferably 1. That is, the formula ^{- [Y 21 -C (= O} ) -O] m '-Y 22 - as indicated by the good Kit formula ^{-Y 21 -C (= O) -OY} 22 - group represented by the. Among them, the formula _{- (CH 2) a '-C} (= O) -O- (CH 2) b' - preferably represented by the group. In the formula, a'is an integer from 1 to 10, preferably an integer from 1 to 8, preferably an integer from 1 to 5, more preferably 1 or 2, and most preferably 1. b'is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, particularly preferably 1 or 2, and most preferably 1.

In the present invention, Ya ^{21 is} preferably a single bond, or an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group or a combination thereof .

In the aforementioned formula (a2-1), Ra ²¹ is a cyclic group containing -SO ₂ -.

"Cyclic group containing -SO ₂ -" refers to a cyclic group containing a ring of -SO ₂ -in the ring skeleton, specifically, the sulfur atom (S) in -SO ₂ -becomes one of the cyclic groups Part of the cyclic group of the cyclic skeleton. The cyclic skeleton containing -SO ₂ - as a ring when independent calculations, simply referred to as a monocyclic group of the ring when the ring, the ring structure further has other structures are called polycyclic group. The cyclic group containing -SO ₂ -may be monocyclic or polycyclic.

The cyclic group containing -SO ₂ -used as a cyclic hydrocarbon group in R ¹ is particularly preferably a cyclic group containing -O-SO ₂ -in the ring skeleton, that is, containing -OS in -O-SO _2- -The cyclic group of the sultone ring which becomes part of the ring skeleton. More specifically, the cyclic group containing -SO ₂ -is a group represented by the following general formulas (a5-r-1) to (a5-r-4).

[式中，Ra’⁵¹為各自獨立的氫原子、烷基、烷氧基、鹵原子、鹵化烷基、羥基、-COOR”、-OC(=O)R”、羥基烷基或氰基；R”為氫原子或烷基；A”為氧原子或可含有硫原子的碳數1~5之伸烷基、氧原子或硫原子，n’為0~2之整數]。

[Wherein, Ra ^'51 are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR ", - OC (= O) R", a hydroxyl group or a cyano group; R" is a hydrogen atom or an alkyl group; A" is an oxygen atom or an alkylene group with 1 to 5 carbon atoms, an oxygen atom or a sulfur atom which may contain a sulfur atom, n'is an integer of 0 to 2].

In the aforementioned general formulas (a5-r-1) to (a5-r-4), A" is the same as A" in the general formulas (a2-r-1) to (a2-r-7) described later. The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", hydroxyalkyl group in Ra' ⁵¹ and the general formula (a2-r-1)~(a2- Ra' ²¹ in r-7) is the same.

The following are specific examples of groups represented by general formulas (a5-r-1) to (a5-r-4). The "Ac" in the formula means acetyl group.

The above-mentioned cyclic group containing -SO ₂ -is preferably the group represented by the aforementioned general formula (a5-r-1), more preferably the group represented by the aforementioned chemical formula (r-sl-1-1), (r-sl -1-18), (r-sl-3-1) and (r-sl-4-1) at least one selected from the group represented. The most preferred is the group represented by the aforementioned chemical formula (r-sl-1-1).

"Lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -O-C(=O)- in its ring skeleton. When calculating the lactone ring as one ring, it is called a monocyclic group when it is only a lactone ring, and if it has other ring structures, the structure is called a polycyclic group. The cyclic group containing the lactone may be a monocyclic group or a polycyclic group.

The lactone-containing cyclic group used as the cyclic hydrocarbon group in R ¹ is not particularly limited, and any one can be used. Specifically, the groups represented by the following general formulas (a2-r-1) to (a2-r-7). The following "*" represents a bonding key.

[式中，Ra’²¹為各自獨立的氫原子、烷基、烷氧基、鹵原子、鹵化烷基、羥基、-COOR”、-OC(=O)R”、羥基烷基或氰基；R”為氫原子或烷基；A”為可含有氧原子或硫原子的碳數1~5之伸烷基、氧原子或硫原子，n’為0~2之整數，m’為0或1]。

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

In the aforementioned general formulas (a2-r-1)~(a2-r-7), A" is an alkylene group with 1 to 5 carbon atoms that may contain an oxygen atom (-O-) or a sulfur atom (-S-) , Oxygen atom or sulfur atom. The alkylene group having 1 to 5 carbon atoms in A" is preferably a straight-chain or branched alkylene group, such as methylene, ethylene, n-propylene, iso Propyl and so on. When the alkylene group contains an oxygen atom or a sulfur atom, specifically, for example, an -O- or -S- group is interposed between the terminal or carbon atoms of the aforementioned alkylene group, such as -O-CH ₂ -, -CH _2- O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH ₂ -, etc. A" is preferably an alkylene having 1 to 5 carbons or -O-, more preferably an alkylene having 1 to 5 carbons, and most preferably a methylene. Ra' ²¹ is an independent alkyl group or alkane Oxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", hydroxyalkyl group, or cyano group.

The alkyl group in Ra' ²¹ is preferably an alkyl group having 1 to 5 carbon atoms.

The alkoxy group in Ra' ²¹ is preferably an alkoxy group having 1 to 6 carbon atoms.

The alkoxy group is preferably linear or branched. Specifically, the alkyl group exemplified in the above-mentioned Ra' ²¹ is connected to an oxygen atom (-O-).

Ra ^'21 halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom, preferably fluorine atom.

Ra ^'21, such as an alkyl halide in the foregoing Ra' of section ²¹ alkyl or all hydrogen atoms are substituted with the aforementioned halogen atom. The halogenated alkyl group is preferably a fluorinated alkyl group, particularly preferably a perfluoroalkyl group.

The following are specific examples of groups represented by general formulas (a2-r-1) to (a2-r-7).

"Carbonate-containing cyclic group" refers to a cyclic group containing a ring (carbonate ring) containing -O-C(=O)-O- in its ring skeleton. When the carbonate ring is used as one ring for calculation, only the carbonate ring is called a monocyclic group, and if there are other ring structures, the structure is called a polycyclic group regardless of the structure. With The cyclic group with carbonate ester may be a monocyclic group or a polycyclic group.

The carbonate ring-containing cyclic group used as the cyclic hydrocarbon group in R ¹ is not particularly limited, and any one can be used. Specifically, the group represented by the following general formulas (ax3-r-1) to (ax3-r-3).

[式中，Ra’^x31為各自獨立的氫原子、烷基、烷氧基、鹵原子、鹵化烷基、羥基、-COOR”、-OC(=O)R”、羥基烷基或氰基；R”為氫原子或烷基；A”為可含有氧原子或硫原子的碳數1~5之伸烷基、氧原子或硫原子，q’為0或1]。

[In the formula, Ra' ^x31 is each independent hydrogen atom, alkyl group, alkoxy group, halogen atom, halogenated alkyl group, hydroxyl group, -COOR", -OC(=O)R", hydroxyalkyl group or cyano group; R" is a hydrogen atom or an alkyl group; A" is an alkylene group with 1 to 5 carbon atoms, an oxygen atom or a sulfur atom that may contain an oxygen atom or a sulfur atom, and q'is 0 or 1].

The A" in the aforementioned general formula (ax3-r-1)~(ax3-r-3) is the same as the A" in the aforementioned general formula (a2-r-1).

The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in Ra' ³¹ are each with the aforementioned general formula (a2-r-1)~ (a2-r-7) The items listed in Ra' ²¹ in (a2-r-7) are the same.

The following are specific examples of groups represented by general formulas (ax3-r-1) to (ax3-r-3).

The above-mentioned cyclic group containing lactone is preferably the group represented by the aforementioned general formula (a2-r-1) or (a2-r-2), more preferably the group represented by the aforementioned chemical formula (r-lc-1-1) base.

(A) The constituent unit (a2) possessed by the component may be one type or two or more types.

When the component (A) has a constituent unit (a2), the ratio of the constituent unit (a2) relative to the total constituent units of the constituent (A) is preferably 1 to 80 mol%, and 5 to 70 mol% Better, more preferably 10~65 mol%, particularly preferably 10~60 mol%. When it is more than the lower limit value, the effect of containing the constituent unit (a2) can be obtained, and when it is less than the upper limit value, it can be balanced with other constituent units, and various lithographic etching characteristics and pattern shapes can be obtained.

(Component Unit (a3))

The constituent unit (a3) is a constituent unit that contains an aliphatic hydrocarbon group containing a polar group (except for those equivalent to the aforementioned constituent units (a1) and (a2)).

It is inferred that the component (A) having the constituent unit (a3) can increase the hydrophilicity of the component (A) and provide enhanced resolution.

Polar groups such as hydroxy, cyano, carboxyl, and hydroxyalkyl in which part of the hydrogen atoms in the alkyl group are substituted by halogen atoms, etc., particularly preferably hydroxy.

The aliphatic hydrocarbon group is, for example, a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group), or a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group. For example, it can be selected from the resins used in the photoresist composition for ArF excimer lasers, and is appropriately selected and used by many proposals. The cyclic group is preferably a polycyclic group, and more preferably has 7 to 30 carbon atoms.

Among them, it is more preferably a structural unit derived from an aliphatic polycyclic acrylate containing a hydroxyl group, a cyano group, a carboxyl group, or an alkyl group in which part of the hydrogen atoms are replaced by a fluorine atom. The polycyclic group is, for example, a group obtained by removing two or more hydrogen atoms from a bicyclic alkane, a tricyclic alkane, or a tetracyclic alkane. Specifically, for example, groups obtained by removing two or more hydrogen atoms from polycyclic alkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, industrially preferred are a group obtained by removing two or more hydrogen atoms from adamantane, a group obtained by removing two or more hydrogen atoms from norbornane, and a group obtained by removing two or more hydrogen atoms from tetracyclododecane. A base derived from more than one hydrogen atom.

The constituent unit (a3) may be a thing containing an aliphatic hydrocarbon group containing a polar group, and any thing may be used without particular limitation.

The structural unit (a3) is preferably a structural unit derived from an acrylate in which a hydrogen atom bonded to a carbon atom at the α -position can be substituted with a substituent, which contains an aliphatic hydrocarbon group.

The constituent unit (a3) is preferably a constituent unit derived from the hydroxyethyl ester of acrylic acid when the hydrocarbon group in the aliphatic hydrocarbon group containing a polar group is a linear or branched hydrocarbon group with 1 to 10 carbon atoms. When it is a polycyclic group, for example, the structural unit represented by the following formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-3) are preferable.

[式中，R與前述相同，j為1~3之整數，k為1~3之整數，t’為1~3之整數，l為1~5之整數，s為1~3之整數]。

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

In formula (a3-1), j is preferably 1 or 2, more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3-position and 5-position of the adamantyl group. When j is 1, preferably, a hydroxyl group is bonded to the 3-position of the adamantyl group.

j is preferably 1, and particularly preferably, the hydroxyl 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 bonded to the 5 or 6 position of the norbornyl group.

In formula (a3-3), t'is preferably 1. l is preferably 1. s is preferably 1. Preferably, the end of the carboxyl group of acrylic acid is bonded to 2-norbornyl or 3- Borneol base. Preferably, the fluorinated alkyl alcohol is bonded to the 5 or 6 position of the norbornyl group.

(A) The constituent unit (a3) contained in the component may be one type or two or more types.

In the component (A), the ratio of the constituent unit (a3) relative to the total of all the constituent units constituting the resin component (A) is preferably 5-50 mol%, and more preferably 5-40 mol%, more preferably It is 5~25 mole%.

When the ratio of the constituent unit (a3) is more than the lower limit value, the effect of containing the constituent unit (a3) can be obtained sufficiently, and when it is less than the upper limit value, it is easy to balance with other constituent units.

(Component Unit (a4))

The structural unit (a4) is a structural unit containing an acid non-dissociable cyclic group. The component (A) can improve the dry corrosion resistance of the formed photoresist pattern by having the constituent unit (a4). In addition, the drainage of the component (A) can be improved. When improving water drainage, especially when developing with organic solvent, it is estimated that it can provide improved resolution, photoresist pattern shape, etc.

The "acid non-dissociable cyclic group" in the constituent unit (a4) refers to the one that can directly remain in the constituent unit when an acid is generated from the component (B) described later by exposure, even if the action of the acid is not dissociated. Cyclic group.

The structural unit (a4) is preferably, for example, a structural unit derived from an acrylate containing an acid non-dissociable aliphatic cyclic group. The cyclic group is, for example, the same as those listed in the aforementioned structural unit (a1), and most of the previously known ArF excimer lasers and KrF excimer lasers can be used (preferably It is used for the resin component of photoresist composition such as ArF excimer laser.

In particular, from the viewpoint of industrial availability, etc., at least one selected from tricyclodecyl, adamantyl, tetracyclododecyl, isobornyl, and norbornyl is preferred. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.

Specific examples of the structural unit (a4) are structures of the following general formulas (a4-1) to (a4-7).

[式中，R^α表示氫原子、甲基或三氟甲基]。

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

(A) The constituent unit (a4) contained in the component may be one type or two or more types.

When the component (A) contains the constituent unit (a4), the ratio of the constituent unit (a4) to the total constituent units of the constituent (A) component is preferably 1 to 30 mol%, more preferably 10 to 20 mol% .

The component (A) can be a copolymer obtained by arbitrarily combining (a1) to (a4).

(A) The component can be used as a radical polymerization initiator like azobisisobutyronitrile (AIBN) and dimethyl azobisisobutyrate The known free radical polymerization method, etc., is obtained by polymerizing monomers that derive each constituent unit.

In addition, component (A) can be combined with a chain transfer agent such as HS-CH ₂ -CH ₂ -CH ₂ -C(CF ₃ ) ₂ -OH during the above polymerization, and the -C(CF ₃ ) ₂ -OH The base is introduced into the end. This type of copolymer containing a hydroxyalkyl group in which part of the hydrogen atoms in the alkyl group is replaced by halogen atoms can effectively reduce the development defects and LER (line end roughness: uneven unevenness of the line sidewall).

In the present invention, the weight average molecular weight (Mw) of component (A) (from the polystyrene conversion standard of gel permeation chromatography) is not particularly limited, and is preferably 1,000 to 50,000, more preferably 1,500 to 30,000, and most preferably 2,000 ~20000. When it is below the upper limit of the range, sufficient solubility with respect to the resist solvent for photoresist can be obtained, and when the range is above the lower limit, good dry corrosion resistance and photoresist can be obtained Figure cross-sectional shape.

In the photoresist composition of the present invention, the component (A) may be used alone or in combination of two or more.

The resin and content of component (A) in the photoresist composition of the present invention can be adjusted according to the required characteristics of the photoresist to be formed, and polyhydroxystyrene resin is preferably used.

<Basic compound component: (D) component>

The photoresist composition of the present invention may further contain an acid diffusion inhibitor component (hereinafter also referred to as "(D) component") in addition to (A) component, or (A) component and (B) component.

The component (D) has a function of an inhibitor (acid diffusion inhibitor) that traps the acid generated by the exposure of the component (B) and the like.

The component (D) of the present invention may be a photodisintegrable base (D1) (hereinafter referred to as "component (D1)") that decomposes and loses acid diffusion inhibitory properties by exposure, or may not correspond to (D1) The nitrogen-containing organic compound (D2) of the component (hereinafter referred to as "(D2) component").

[(D1) Ingredients]

The photoresist composition containing the component (D1) can improve the contrast between the exposed part and the non-exposed part when forming a photoresist pattern.

The component (D1) is a substance that decomposes and loses acid diffusion inhibitory properties by exposure to light, and is preferably a compound represented by the following general formula (d1-1) (hereinafter referred to as (d1-1) component") , The compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component") and the compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1-3) ) Ingredients") is a compound selected from the group.

The components (d1-1) to (d1-3) do not have an inhibitory effect that loses acid diffusion inhibition (basicity) due to decomposition in the exposed part, but have an inhibitory effect in the unexposed part.

[式中，Rd¹~Rd⁴為可具有取代基之環式基、可具有取代基之鏈狀烷基、或可具有取代基之鏈狀鏈烯基。但式(d1-2)中之Rd²中接鄰於S原子之碳原子不鍵結氟原子。Yd¹為單鍵或二價連結基。M^m+為各自獨立的m價之有機陽離子]。

[In the formula, Rd ¹ to Rd ⁴ are cyclic groups which may have substituents, chain alkyl groups which may have substituents, or chain alkenyl groups which may have substituents. However, the carbon atom adjacent to the S atom in Rd ² in formula (d1-2) is not bonded to a fluorine atom. Yd ¹ is a single bond or a divalent linking group. M ^m+ is an independent m-valent organic cation].

{(d1-1) Ingredients}

‧Anion Department

In the formula (d1-1), Rd ¹ 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, for example, the same as R ¹⁰¹ .

Among them, Rd ^{1 is} preferably an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain hydrocarbon group which may have a substituent. The substituents that these groups may have are preferably a hydroxyl group, a fluorine atom or a fluorinated alkyl group.

The aforementioned aromatic hydrocarbon group is more preferably phenyl or naphthyl.

The aforementioned aliphatic cyclic group is more preferably a group obtained by removing more than one hydrogen atom from a polycyclic alkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

The aforementioned chain hydrocarbon group is preferably a chain alkyl group, and the chain alkyl group preferably has a carbon number of 1-10, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl. , Nonyl, decyl and other linear alkyl groups; 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3 -Methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, etc. Chain alkyl.

When the aforementioned chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group used as a substituent, the carbon number of the fluorinated alkyl group is preferably 1 to 11, preferably 1 to 8, and more preferably It is 1~4. The fluorinated alkyl group may contain atoms other than fluorine atoms. Atoms other than fluorine atoms include oxygen atoms, carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.

Rd ^{1 is} preferably a fluorinated alkyl group in which part or all of the hydrogen atoms constituting the linear alkyl group are replaced by fluorine atoms, and a fluorinated alkyl group in which all of the hydrogen atoms constituting the linear alkyl group are replaced by fluorine atoms (straight chain Chain perfluoroalkyl) is preferred.

The following are preferred specific examples of the anion part of the component (d1-1).

‧Cation Department

In the formula (d1-1), M ^m+ is an organic cation of m valence.

The organic cation of M ^m+ is not particularly limited. For example, it is the same as the cation represented by each of the aforementioned general formulas (ca-1)~(ca-4), preferably the aforementioned formulas (ca-1-1)~(ca-1 -63) The cation represented by each.

(d1-1) A component can be used individually by 1 type or in combination of 2 or more types.

{(d1-2) Ingredients}

‧Anion Department

In the formula (d1-2), Rd ² 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, for example, the same as R ¹⁰¹ .

However, the carbon atom adjacent to the S atom in Rd ² is not bonded to a fluorine atom (not substituted by fluorine). Thereby, the anion of the component (d1-2) can be a moderately weak acid anion, and the inhibitory performance of the component (D) can be improved.

Rd ^{2 is} preferably an aliphatic cyclic group which may have a substituent, more preferably obtained by removing more than one hydrogen atom from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. Group (which may have substituents); a group obtained by removing more than one hydrogen atom from campane.

The hydrocarbon group of Rd ² may have a substituent, and the substituent is the same as that of the hydrocarbon group (aromatic hydrocarbon group, aliphatic hydrocarbon group) in Rd ¹ of the aforementioned formula (d1-1).

The following are preferred specific examples of the anion part of the component (d1-2).

‧Anion Department

In the formula (d1-2), M ^m+ is an organic cation of m valence, which is the same as M ^m+ in the aforementioned formula (d1-1).

(d1-2) The component can be used alone or in combination of two or more.

{(d1-3) Ingredients}

‧Anion Department

In the formula (d1-3), Rd ³ 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, for example, the same as R ¹⁰¹ , Preferably, it is a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group. Among them, the fluorinated alkyl group is preferred, and the same as the fluorinated alkyl group of Rd ^{1 is more} preferred.

In the formula (d1-3), Rd ⁴ 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, for example, the same as R ¹⁰¹ .

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 straight-chain or branched-chain alkyl group with 1 to 5 carbon atoms, specifically, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, etc. Part of the hydrogen atoms in the alkyl group of Rd ⁴ may be substituted by hydroxyl groups, cyano groups and the like.

The alkoxy group in Rd ⁴ is preferably an alkoxy group with a carbon number of 1 to 5, and specific examples of the alkoxy group with a carbon number of 1 to 5 are methoxy, ethoxy, n-propoxy, iso-propoxy Group, n-butoxy, tert-butoxy. Among them, methoxy and ethoxy are preferred.

The alkenyl group in Rd ⁴ is, for example, the same as the above-mentioned R ¹⁰¹ , preferably vinyl, propenyl (allyl), 1-methpropenyl, and 2-methpropenyl. These groups may additionally have an alkyl group with 1 to 5 carbons or a halogenated alkyl group with 1 to 5 as a substituent.

The cyclic group in Rd ⁴ is, for example, the same as the above-mentioned R ²¹ , preferably from cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane Cycloalkanes such as alicyclic groups with more than one hydrogen atom removed, or aromatic groups such as phenyl and naphthyl. When Rd ⁴ is an alicyclic group, the photoresist composition can be well dissolved in organic solvents, resulting in good lithographic etching characteristics. In addition, when Rd ⁴ is an aromatic group, the photoresist composition can achieve excellent light absorption efficiency in lithographic etching using EUV or the like as an exposure light source, as well as good sensitivity and lithographic etching characteristics.

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, and for example, a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) that may have a substituent, a heteroatom-containing divalent linking group, and the like. These respective examples are the same as those listed in the description of the bivalent linking group of Ya ^{21 in} the aforementioned formula (a2-1).

Yd ^{1 is} preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is preferably a linear or branched alkylene group, more preferably a methylene group or an ethylene group.

The following are preferred specific examples of the anion part of the component (d1-3).

‧Cation Department

In the formula (d1-3), M ^m+ is an organic cation of m valence, which is the same as M ^m+ in the aforementioned formula (d1-1).

(d1-3) The component can be used singly or in combination of two or more.

(D1) As a component, only any one of the above-mentioned (d1-1) to (d1-3) components can be used, or two or more types can be used in combination.

The content of the component (D1) is preferably 0.5-10 parts by mass relative to 100 parts by mass of the component (A), preferably 0.5-8 parts by mass, and more preferably 1-8 parts by mass.

When the content of the component (D1) is more than the preferable lower limit, particularly good lithographic etching characteristics and photoresist pattern shape can be obtained. In addition, when it is below the upper limit, good sensitivity can be maintained and good throughput can be obtained.

The production method of the aforementioned (d1-1) component and (d1-2) component is not particularly limited, and can be produced by a known method.

The content of the component (D1) is preferably 0.5 to 10.0 parts by mass relative to 100 parts by mass of the component (A), preferably 0.5 to 8.0 parts by mass, and more preferably 1.0 to 8.0 parts by mass. When it is above the lower limit of the above range, particularly good lithographic etching characteristics and photoresist pattern shape can be obtained. In addition, when it is below the upper limit of the aforementioned range, good sensitivity can be maintained and good throughput can be obtained.

((D2) Ingredient)

The component (D) may contain a nitrogen-containing organic compound component that does not correspond to the component (D1) (hereinafter referred to as the component (D2)).

The component (D2) is a substance having an acid diffusion inhibitor effect, and it is not equivalent to the component (D1), and is not particularly limited, and can be arbitrarily used from known substances. Among them, aliphatic amines are preferred, and secondary aliphatic amines and tertiary aliphatic amines are particularly preferred.

Aliphatic amine refers to an amine having more than one aliphatic group, and the aliphatic group preferably has 1 to 12 carbon atoms.

Aliphatic amines such as amines (alkylamines or alkyl alcohol amines) or cyclic amines in which at least one of the hydrogen atoms of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group with a carbon number of 12 or less.

Specific examples of alkyl amines and alkyl alcohol amines include monoalkyl amines such as n-hexyl amine, n-heptyl amine, n-octyl amine, n-nonyl amine, and n-decyl amine; diethyl Dialkylamines such as amine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, dicyclohexylamine, etc.; trimethylamine, triethylamine, tri-n -Propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonyl Amine, tri-n-decylamine, tri-n-dodecylamine and other trialkylamines; diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanol Alkyl alcohol amines such as amines and tri-n-octanol. Among these, trialkylamines having 5 to 10 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine is particularly preferred.

The cyclic amine is, for example, a heterocyclic compound containing a nitrogen atom as a heteroatom. The heterocyclic compound can be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).

Specific examples of aliphatic monocyclic amines include piperidine and piperazine.

The aliphatic polycyclic amine is preferably a substance with 6 to 10 carbon atoms, specifically, for example, 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[ 5.4.0]-7-undecene, hexamethylenetetramine, 1,4-diazabicyclo[2.2.2]octane, etc.

Other aliphatic amines such as tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxy Ethoxymethoxy)ethyl)amine, tris{2-(1-methoxyethoxy)ethyl}amine, tris{2-(1-ethoxyethoxy)ethyl}amine, Tri{2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-hydroxyethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, etc., preferably Triethanolamine triacetic acid ester.

In addition, as the component (D2), aromatic amines can be used.

Aromatic amines such as aniline, pyridine, 4-lutidine, pyrrole, indole, pyrazole, imidazole or their derivatives, diphenylamine, triphenylamine, tribenzylamine, 2,6- Diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, etc.

(D2) Components can be used alone or in combination of two or more kinds.

The usage amount of (D2) component with respect to 100 parts by mass of (A) component is generally 0.01 to 5.0 parts by mass. With the above range, the shape of the photoresist pattern and the stability over time can be improved.

(D) The component can be used alone or in combination of two or more.

When the photoresist composition of the present invention contains component (D), component (D) is preferably 0.1-15 parts by mass relative to 100 parts by mass of component (A), more preferably 0.3-12 parts by mass, more preferably 0.5 ~12 parts by mass. When it is more than the lower limit of the above range, the photoresist composition can further improve the lithographic etching characteristics such as LWR. In addition, a better photoresist pattern shape can be obtained. In addition, when it is below the upper limit of the aforementioned range, good sensitivity can be maintained and good throughput can be obtained.

<Arbitrary Ingredients>

[(E) Ingredient]

The photoresist composition of the present invention is to prevent the sensitivity from becoming Resistant pattern shape, stability over time, etc., can contain at least one compound (E) selected from the group of organic carboxylic acids, phosphorus oxyacids and their derivatives (hereinafter referred to as (E) )ingredient).

Organic carboxylic acids are preferably, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like.

Phosphorous oxo acids include phosphoric acid, phosphonic acid, phosphinic acid, etc., among which phosphonic acid is particularly preferred.

Derivatives of phosphorus oxo acids include esters in which the hydrogen atoms of the above oxo acids are substituted with hydrocarbon groups, and the aforementioned hydrocarbon groups include alkyl groups with 1 to 5 carbons, aryl groups with 6 to 15 carbons, and the like.

Phosphoric acid derivatives such as phosphate di-n-butyl phosphate, diphenyl phosphate, etc.

Phosphonic acid derivatives such as phosphonates such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, dibenzyl phosphonate, etc.

Derivatives of phosphinic acid, such as phosphinate, phenylphosphinic acid, etc.

(E) A component can be used individually by 1 type or in combination of 2 or more types.

The usage amount of (E) component relative to 100 parts by mass of (A) component is generally 0.01 to 5.0 parts by mass.

[(F) Ingredient]

In the present invention, the photoresist composition may contain a fluorine additive (hereinafter referred to as "(F) component") in order to impart water repellency to the photoresist film.

(F) For the component, for example, Japanese Patent Application Publication No. 2010-002870 Fluorine-containing polymer compounds described in Japanese Patent Publication, Japanese Patent Application Publication No. 2010-032994, Japanese Patent Application Publication No. 2010-277043, Japanese Patent Application Publication No. 2011-13569, and Japanese Patent Application Publication No. 2011-128226.

The (F) component is more specifically, a polymer having a structural unit (f1) represented by the following formula (f1-1). The aforementioned polymer is preferably a polymer (homopolymer) formed only by the structural unit (f1) represented by the following formula (f1-1); the structural unit (f1-1) represented by the following formula (f1-1) f1), a copolymer with the aforementioned structural unit (a1); the structural unit (f1) represented by the following formula (f1-1), and the structural unit derived from acrylic acid or methacrylic acid, and the aforementioned structural unit (a1) ) Of the copolymer. Among them, the aforementioned structural unit (a1) copolymerized with the structural unit (f1) represented by the following formula (f1-1) is preferably 1-ethyl-1-cyclooctyl (meth)acrylate or the aforementioned formula ( a1-2-01) indicates the constituent unit.

[式中，R與前述相同，Rf¹⁰²及Rf¹⁰³表示各自獨立的氫原子、鹵原子、碳數1~5之烷基，或碳數1~5之鹵化烷基，Rf¹⁰²及Rf¹⁰³可相同或相異。nf¹為1~5之整數，Rf¹⁰¹為含有氟原子之有機基]。

[In the formula, R is the same as the above, Rf ¹⁰² and Rf ¹⁰³ represent independent hydrogen atoms, halogen atoms, alkyl groups with 1 to 5 carbons, or halogenated alkyl groups with 1 to 5 carbons. Rf ¹⁰² and Rf ¹⁰³ can be Same or different. nf ¹ is an integer of 1 to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom].

In the formula (f1-1), R is the same as described above. R is preferably a hydrogen atom or a methyl group.

In the formula (f1-1), the halogen atoms of Rf ¹⁰² and Rf ¹⁰³ include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., particularly preferably a fluorine atom. The alkyl group having 1 to 5 carbon atoms in Rf ¹⁰² and Rf ^{103 is} the same as the alkyl group having 1 to 5 carbon atoms in R, preferably methyl or ethyl. Specific examples of the halogenated alkyl groups having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ^{103 are} groups in which part or all of the hydrogen atoms in the above-mentioned 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, etc., and a fluorine atom is particularly preferable. Among them, Rf ¹⁰² and Rf ^{103 are} preferably a hydrogen atom, a fluorine atom or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom, a fluorine atom, a methyl group or an ethyl group.

In formula (f1-1), nf ¹ is an integer of 1 to 5, preferably an integer of 1 to 3, and more preferably 1 or 2.

In formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, preferably a hydrocarbon group containing a fluorine atom.

The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has a carbon number of 1-20, more preferably a carbon number of 1-15, and particularly preferably a carbon number of 1-10.

In addition, the hydrocarbon group containing fluorine atoms is preferably that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more are fluorinated, and when 60% or more is fluorinated, the photoresist film can be improved by immersion exposure. The drainage is particularly good.

Among them, Rf ^{101 is} particularly preferably a fluorinated hydrocarbon group with carbon number of 1 to 5, most preferably methyl, -CH ₂ -CF ₃ , -CH ₂ -CF ₂ -CF ₃ , -CH(CF ₃ ) ₂ , -CH ₂ -CH ₂ -CF ₃ , -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF ₃ .

(F) The weight average molecular weight (Mw) of the component (from the polystyrene conversion standard of gel permeation chromatography) is preferably 1,000 to 50,000, more preferably 5,000 to 40,000, and most preferably 10,000 to 30,000. When it is below the upper limit of the range, sufficient solubility with respect to the resist solvent when used as a photoresist can be obtained, and when it is above the lower limit of the range, good dry etching resistance and photoresist can be obtained Figure cross-sectional shape.

(F) The dispersion (Mw/Mn) of the component is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

(F) A component can be used individually by 1 type or in combination of 2 or more types.

The usage amount of (F) component relative to 100 parts by mass of (A) component is generally 0.5-10 parts by mass.

The photoresist composition of the present invention may additionally contain mixing additives as desired, such as additional resins for improving the performance of the photoresist film, dissolution inhibitors, plasticizers, stabilizers, colorants, and light protection Halo agents, dyes, etc.

[(S) Ingredient]

The photoresist composition in the present invention can be obtained by dissolving the material in an organic solvent (hereinafter referred to as (S) component).

The (S) component can be a substance that can dissolve each component used to obtain a uniform solution, and one or two or more of the known substances previously used as solvents for chemically enhanced photoresist can be appropriately selected.

等之芳香族系有機溶劑、二甲基亞碸(DMSO)等。 For example, lactones such as γ-butyrolactone; acetone, methyl ethyl ketone (MEK), cyclohexanone, methyl-n-pentyl ketone (2-pentyl ketone), methyl isoamyl ketone, etc. Ketones; ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol and other multivalent alcohols; ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol Compounds with ester bonds such as monoacetate, monoalkyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, etc. of the aforementioned polyvalent alcohols or the aforementioned compound having ester bonds Or derivatives of polyvalent alcohols such as compounds with ester bonds such as monophenyl ethers [of which propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred]; Alkane-like cyclic ethers, or methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, Ethoxy ethyl propionate and other esters; anisole, ethyl benzyl ether, cresol methyl ether, diphenyl ether, dibenzyl ether, phenethyl ether, butyl phenyl ether, ethyl benzene, Diethylbenzene, pentylbenzene, cumene, toluene, xylene, cymene,

Such as aromatic organic solvents, dimethyl sulfide (DMSO), etc.

These organic solvents can be used alone or a mixed solvent of two or more kinds can be used.

Among them, PGMEA, PGME, γ-butyrolactone, and EL are preferred.

More preferably, it is a mixed solvent obtained by mixing PGMEA and a polar solvent. The addition ratio (mass ratio) can be appropriately determined in consideration of the compatibility of PGMEA and the polar solvent, etc., preferably in the range of 1:9-9:1, more preferably in the range of 2:8-8:2.

More specifically, when the polar solvent to be added is EL or cyclohexanone, the quality of PGMEA: EL or cyclohexanone is preferably 1:9-9:1, even better It is 2:8~8:2. Moreover, when the polar solvent added is PGME, the quality of PGMEA:PGME is preferably 1:9-9:1, and 2:8-8:2 is better, and more preferably 3:7-7:3.

In addition, the (S) component is preferably another mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone. The mixing ratio at this time is preferably, the mass ratio of the former to the latter is 70:30~95:5.

The amount of (S) component used is not particularly limited, and can be appropriately set according to the coating film thickness at a concentration that can be applied to a substrate or the like. Generally, the solid content concentration of the photoresist composition is 1 to 20% by mass, preferably 2 to 15% by mass.

The photoresist composition of the present invention may optionally contain additives with mixing properties, such as additional resins for improving the performance of the photoresist film, dissolution inhibitors, plasticizers, stabilizers, colorants, and antihalation agents. , Dyes, etc.

The photoresist pattern forming method and photoresist composition of the present invention can form a photoresist pattern with good lithographic etching characteristics even when a support with high reflectivity such as a stepped substrate is used. The reason is inferred as follows.

In the present invention, since the compound (b1) has an ether group (that is, an oxygen atom) in the cation portion, it is estimated that the polarity is relatively high and can be uniformly distributed in the photoresist film. Therefore, it is inferred that the tip shape when the focus is changed can be maintained. In addition, since the anion part of (b1) is small, it is estimated that the diffusion of acid tends to be long. As a result, the acid diffusion in the exposed part can reduce the roughness of the side wall.

In addition, in (b2), the anion part is a huge structure with a high three-dimensional volume. Therefore, it is inferred that the anion part (acid) can be inhibited chemically and physically. Scattered.

It is inferred that the present invention can use the multiplication of (b1) and (b2) to form a photoresist pattern with good lithographic etching characteristics even when the reflectivity of the support is high.

[Example]

The following examples will be given to illustrate the present invention more specifically, but the present invention is not limited to the following examples.

<modulated photoresist composition>

The components shown in Table 1 were mixed and dissolved to prepare a photoresist composition.

The codes in the above table have the following meanings. Also, the value in [] is the addition amount (parts by mass).

(A)-1: The following polymer compound (A)-1.

(B-1)~(B-2), (B-11), (B-21)~(B-22), (B-3): the following compounds (B-1)~(B-2) , (B-11), (B-21)~(B-22), (B-3).

(D)-1: Trioctylamine.

(E)-1: Salicylic acid.

(S)-1: PGMEA/PGME/ethyl lactate (mass ratio 50/25/25) mixed solvent.

<Formation of photoresist pattern>

After applying a known organic anti-reflection film composition on an 8-inch silicon wafer using a spin coater, it is baked on a hot plate at 205°C for 60 seconds to dry to form an organic anti-reflection film with a thickness of 120 nm. Coating organic reflective film substrate.

Measure the n value (light refractive index) and k value (light absorptivity) of the coated organic reflective film substrate when irradiated with light with a wavelength of 248 nm, and then calculate the reflectance. The result is that the reflectance of the coated organic anti-reflective film substrate is 6.6%.

Secondly, after each photoresist composition of Examples 1 to 3 and Comparative Examples 1 to 3 was coated on the coated organic anti-reflection film substrate using a spin coater, the hot plate was preheated at a temperature of 120°C for 90 seconds ( PAB) treatment and drying to form a photoresist film with a thickness of 277nm.

Next, use the exposure device NSR-S205C (NA=0.751/2annular made by Nikon), and set the KrF under each mask pattern (binary mask) An excimer laser (248nm) is selectively irradiated on the photoresist film.

Next, at 23°C, a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used to perform alkali development for 60 seconds.

Thereafter, a post-exposure heat treatment (PEB) was performed at 120°C for 90 seconds.

As a result, the following patterns were formed respectively.

Pattern 1: Space and line (SL) pattern with a space width of 120nm and a pitch of 260nm

Pattern 2: Space and line pattern with a space width of 120nm and a pitch of 1650nm

Pattern 3: Line and Space (LS) pattern with a line width of 120nm and a pitch of 1760nm

[Evaluation of the best exposure (Eop)]

Obtain the optimal exposure Eop (mJ/cm ² ) of the LS pattern of the target size formed by the above-mentioned photoresist pattern forming method. The results are expressed as "sensitivity (mJ/cm ² )", as shown in Table 2.

[Evaluation shape]

After the above-mentioned photoresist pattern is formed, the LS pattern is observed by a length measuring SEM (scanning electron microscope, acceleration voltage 800V, trade name: S-9220, manufactured by Hitachi, Ltd.). The results are expressed as "the shape of the side wall of the pattern" or "the shape of the top of the pattern", as shown in Table 2.

In the following Table 2, the evaluation method of "the shape of the patterned side wall" is as follows: when the patterned sidewall slides down with excellent rectangularity, it is regarded as ◎, and the patterned sidewall is rough as ×.

In the following Table 2, the evaluation method of "the shape of the top of the pattern" is that the shape of the top is disintegrated as ×, and the shape of the top is not disintegrated as ◎.

[Assess the depth of focus (DOF)]

The depth of focus (DOF) is evaluated after the formation of the above-mentioned photoresist pattern.

In the above-mentioned Eop, the focus is moved up and down moderately, and when the photoresist pattern is formed as in Examples 1 to 3 and Comparative Examples 1 to 3, the shape of the SL pattern or the LS pattern is obtained. The depth of focus amplitude (nm). The results are shown in Table 2.

As shown in the above results, when using the photoresist composition of Examples 1 to 3 to form a photoresist pattern, compare the photoresist pattern formed by using the photoresist composition of Comparative Examples 1 to 3, a good pattern can be obtained Shape, and can form a good DOF pattern.

Claims (6)

A method for forming a photoresist pattern, which includes the step of forming a photoresist film by using a photoresist composition that generates acid by exposure on a support and changes the solubility with respect to a developing solution by the action of the acid , And a photoresist pattern forming method of the step of exposing the photoresist film and the step of developing the photoresist film to form a photoresist pattern, the photoresist composition contains an acid generator, and the acid generates The agent contains the compound (b1) represented by the following general formula (b1-1) and the compound (b2) represented by the following general formula (b2). In the formula (b2), M'm ⁺ is a cation or iodine Onium cation,

[In the formula, R ¹¹ to R ¹³ represent independent aryl, alkyl or alkenyl groups that may have substituents, but at least one of R ¹¹ to R ¹³ contains an ether group, and R ¹¹ to R ¹³ can be bonded to each other It forms a ring with the sulfur atom in the formula; R ⁴¹ is a chain fluorinated alkyl],

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ Is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence]. The photoresist pattern forming method according to claim 1, wherein the reflectance of the aforementioned support to light of the wavelength of the exposure light source is 1.0% or more. The photoresist pattern forming method of claim 1 or 2, wherein the photoresist composition contains at least one resin selected from the group consisting of novolak resin, polyhydroxystyrene resin and acrylic resin. A photoresist composition characterized in that an acid is generated by exposure to light, and the photoresist composition that changes solubility with respect to a developing solution by the action of the acid contains an acid generator, and the aforementioned acid generator Contains, the compound (b1) represented by the following general formula (b1-1), and the compound (b2) represented by the following general formula (b2), in the formula (b2), M'm ⁺ is a cation or iodonium cation,

[In the formula, R ¹¹ to R ¹³ represent independent aryl, alkyl or alkenyl groups that may have substituents, but at least one of R ¹¹ to R ¹³ contains an ether group, and R ¹¹ to R ¹³ can be bonded to each other It forms a ring with the sulfur atom in the formula; R ⁴¹ is a chain fluorinated alkyl],

[In the formula, R ²¹ is a cyclic group that may have a substituent; R ²² is a fluorine atom or a fluorinated alkyl group with 1 to 5 carbon atoms; Y ²¹ is a single bond or a divalent linking group containing an oxygen atom; V ²¹ Is a single bond, alkylene, or fluorinated alkylene; M'm ⁺ is an organic cation with m valence]. Such as the photoresist composition of claim 4, which is used for forming a photoresist pattern on a support with a reflectance of 1.0% or more to light of the wavelength of the exposure light source. The photoresist composition of claim 4 or 5, which contains at least one resin selected from the group consisting of novolac resin, polyhydroxystyrene resin and acrylic resin.