JP2011059531A - Radiation-sensitive resin composition and method for forming pattern - Google Patents

Abstract

【選択図】なしA negative resist capable of effectively responding to (extreme) deep ultraviolet rays such as KrF excimer laser and ArF excimer laser, excellent in nano edge roughness, sensitivity and resolution, and capable of forming a fine pattern with high accuracy and stability. A radiation-sensitive resin composition capable of forming a film.
(A) a polymer containing at least one of an oxetanyl group and an epoxy group and at least one of a carboxyl group and a phenolic hydroxyl group in a side chain; and (B) the following general formula (b1) Or a compound represented by (b2).

[Selection figure] None

Description

The present invention relates to a radiation-sensitive resin composition and a pattern forming method. More specifically, the present invention relates to various types of radiation such as KrF excimer laser, ArF excimer laser, F ₂ excimer laser, EUV and other (extreme) far ultraviolet rays, synchrotron radiation and other X-rays, electron beam and other charged particle beams. The present invention relates to a radiation sensitive resin composition used as a chemically amplified resist suitable for microfabrication by the method and a pattern forming method using the same.

In lithography technology, for example, a resist film made of a resist material is formed on a support such as a substrate, and radiation such as light and electron beams is passed through a mask in which a predetermined pattern is formed on the resist film. A step of forming a resist pattern having a predetermined shape on the resist film is performed by performing selective exposure at, and performing development processing. A resist material in which the exposed portion changes to a property that dissolves in the developer is referred to as a positive type, and a resist material that changes to a property in which the exposed portion does not dissolve in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has rapidly progressed due to advances in lithography technology. As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but at present, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. In addition, studies have been conducted on F ₂ excimer lasers having a shorter wavelength than these excimer lasers, electron beams, EUV (extreme ultraviolet rays), X-rays, and the like.

  Negative resist materials used in processes using i-line or KrF excimer laser light (wavelength 248 nm) as the light source include acid generators, alkali-soluble resins such as novolac resins and polyhydroxystyrene, melamine resins and urea resins, etc. A negative resist composition containing a combination with an amino resin is used (for example, see Patent Document 1).

  Further, as a negative resist material applied to a process using ArF excimer laser light having a short wavelength (wavelength 193 nm), for example, a resin component having a carboxy group, an alcoholic hydroxyl group, having improved transparency with respect to ArF excimer laser There has been proposed a negative resist composition containing a crosslinking agent having an acid generator and an acid generator. This is a type in which the resin component is changed from alkali-soluble to insoluble by the reaction of the carboxy group of the resin component and the alcoholic hydroxyl group of the crosslinking agent by the action of the acid generated from the acid generator. A negative resist composition comprising a resin component having both a carboxy group or carboxylic acid ester group and an alcoholic hydroxyl group, and an acid generator, wherein the carboxy group or carboxylic acid ester group and the alcoholic hydroxyl group in the resin component Has been proposed in which the resin component is changed from alkali-soluble to insoluble by reacting with each other by the action of an acid generated from an acid generator (see, for example, Patent Document 2).

JP-A-62-164045 JP 2000-206694 A

  However, in any combination of the negative resist composition etc., high sensitivity, high resolution, good pattern shape, and good nano edge roughness (low roughness) are not satisfied at the same time in the ultrafine region. Is the current situation.

  The present invention has been made in view of the above circumstances, and is effectively sensitive to X-rays such as KrF excimer lasers, ArF excimer lasers, EUV (extreme) deep ultraviolet rays, synchrotron radiation, and electron beams, and nanoedges. Disclosed is a radiation-sensitive resin composition capable of forming a negative resist film that is excellent in roughness, sensitivity, and resolution, and that can form a fine pattern with high accuracy and stability, and a pattern forming method using the same. With the goal.

〔一般式（ｂ１）及び（ｂ２）において、Ｒ^３１〜Ｒ^３５は、それぞれ独立に、水素原子、フッ素原子、トリフルオロメチル基、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、炭素数５〜２５のシクロアルキル基、−Ｓ−Ｒ^３６基、−Ｏ−ＳＯ_２−Ｒ^３７基、又は、−ＳＯ_２−Ｒ^３８基を示す（但し、Ｒ^３６〜Ｒ^３８は、それぞれ独立に、フッ素原子で置換若しくは非置換の炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、フッ素原子で置換若しくは非置換の炭素数５〜２５のシクロアルキル基、フッ素原子で置換若しくは非置換の炭素数６〜２２のアリール基を示す。）。Ｘ_１ ⁻及びＸ_２ ⁻は、それぞれ独立に、ＯＨ⁻、Ｒ^３９Ｏ⁻、又は、Ｒ^４０ＣＯＯ⁻を示す（但し、Ｒ^３９及びＲ^４０は、それぞれ独立に、フッ素原子で置換若しくは非置換の炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、フッ素原子で置換若しくは非置換の炭素数５〜２５のシクロアルキル基、又は、フッ素原子、トリフルオロメチル基、及びヒドロキシル基のうちの少なくとも１種で置換若しくは非置換の炭素数６〜２２のアリール基を示す。）。〕
［２］前記重合体が、下記一般式（１−ａ）及び（１−ｂ）で表される繰り返し単位のうちの少なくとも一方と、下記一般式（２）〜（７）で表される繰り返し単位のうちの少なくとも１種と、を含む前記［１］に記載の感放射線性樹脂組成物。

〔一般式（１−ａ）において、Ｒ^１は水素原子又は炭素数１〜４のアルキル基を示す。Ｒ^２は水素原子又は炭素数１〜４のアルキル基を示す。Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は、それぞれ独立に、水素原子、フッ素原子、炭素数１〜４のアルキル基、フェニル基、又は炭素数１〜４のパーフルオロアルキル基を示す。ｎは１〜６の整数である。〕

〔一般式（１−ｂ）において、Ｒ^１は水素原子又は炭素数１〜４のアルキル基を示す。Ｒ^２は水素原子又は炭素数１〜４のアルキル基を示す。ｎは１〜６の整数である。〕

〔一般式（２）において、Ｒ^７は水素原子又はメチル基を示す。Ｒ^８及びＲ^９は、それぞれ独立に、メチレン基、炭素数２〜６の直鎖状若しくは分岐状のアルキレン基、又は炭素数４〜１２の脂環式のアルキレン基を示す。〕

〔一般式（３）において、Ｒ^１０は水素原子又はメチル基を示す。Ｒ^１１はメチレン基、炭素数２〜６の直鎖状若しくは分岐状のアルキレン基、又は炭素数４〜１２の脂環式のアルキレン基を示す。〕

〔一般式（４）において、Ｒ^１２は水素原子又はメチル基を示す。〕

〔一般式（５）において、Ｒ^１３は水素原子又はメチル基を示す。Ｒ^１４は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシル基を示す。ｉ及びｊは、それぞれ独立に、０〜３の整数を示す（但し、ｉ＋ｊ≦５を満たす。）。〕

〔一般式（６）において、Ｒ^１５は水素原子又はメチル基を示す。Ｒ^１６は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシル基を示す。ｋ及びｌは、それぞれ独立に、０〜３の整数を示す（但し、ｋ＋ｌ≦５を満たす。）。〕

〔一般式（７）において、Ｒ^１７は水素原子又はメチル基を示す。Ｒ^１８は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシル基を示す。ｍ及びｎは、それぞれ独立に、０〜３の整数を示す（但し、ｍ＋ｎ≦５を満たす。）。〕
［３］（１）前記［１］又は［２］に記載の感放射線性樹脂組成物を用いてレジスト膜を形成する工程と、
（２）得られたレジスト膜を、ＫｒＦエキシマレーザー、ＡｒＦエキシマレーザー、電子線（ＥＢ）又は極紫外線（ＥＵＶ）を用いて露光する工程と、を備えることを特徴とするパターン形成方法。 The present invention is as follows.
[1] (A) a polymer containing at least one of an oxetanyl group and an epoxy group and at least one of a carboxyl group and a phenolic hydroxyl group in a side chain;
(B) A radiation-sensitive resin composition comprising: a compound represented by the following general formula (b1) or (b2):

[In General Formulas (b1) and (b2), R ^{31 to} R ³⁵ are each independently a hydrogen atom, a fluorine atom, a trifluoromethyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, A cycloalkyl group having 5 to 25 carbon atoms, -S-R ³⁶ group, -O-SO ₂ -R ³⁷ group, or -SO ₂ -R ³⁸ group (provided that R ^{36 to} R ³⁸ are each independently A linear or branched alkyl group having 1 to 12 carbon atoms substituted or unsubstituted with a fluorine atom, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted with a fluorine atom, or substituted or non-substituted with a fluorine atom. A substituted aryl group having 6 to 22 carbon atoms is shown.). X ₁ ^- and _{X 2} ^- are each ^{independently, OH -, R 39 O -} , ^or, R 40 COO ^- showing the ^{(where, R 39} and ^{R 40} each independently represent a substituted or unsubstituted with fluorine atom A linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted by a fluorine atom, or a fluorine atom, a trifluoromethyl group, and a hydroxyl group. And a substituted or unsubstituted aryl group having 6 to 22 carbon atoms. ]
[2] The polymer is a repeat represented by at least one of repeating units represented by the following general formulas (1-a) and (1-b) and the following general formulas (2) to (7). The radiation-sensitive resin composition according to [1], including at least one unit.

[In General Formula (1-a), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ³ , R ⁴ , R ⁵ and R ⁶ each independently represent a hydrogen atom, a fluorine atom, an alkyl group having 1 to 4 carbon atoms, a phenyl group, or a perfluoroalkyl group having 1 to 4 carbon atoms. n is an integer of 1-6. ]

[In General Formula (1-b), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is an integer of 1-6. ]

[In General Formula (2), R ⁷ represents a hydrogen atom or a methyl group. R ⁸ and R ⁹ each independently represent a methylene group, a linear or branched alkylene group having 2 to 6 carbon atoms, or an alicyclic alkylene group having 4 to 12 carbon atoms. ]

[In General Formula (3), R ¹⁰ represents a hydrogen atom or a methyl group. R ¹¹ represents a methylene group, a linear or branched alkylene group having 2 to 6 carbon atoms, or an alicyclic alkylene group having 4 to 12 carbon atoms. ]

In [Formula ^{(4), R 12} represents a hydrogen atom or a methyl group. ]

[In General Formula (5), R ¹³ represents a hydrogen atom or a methyl group. R ¹⁴ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxyl group having 1 to 12 carbon atoms. i and j each independently represent an integer of 0 to 3 (provided that i + j ≦ 5 is satisfied). ]

In [Formula ^{(6), R 15} represents a hydrogen atom or a methyl group. R ¹⁶ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxyl group having 1 to 12 carbon atoms. k and l each independently represent an integer of 0 to 3 (provided that k + l ≦ 5 is satisfied). ]

[In General Formula (7), R ¹⁷ represents a hydrogen atom or a methyl group. R ¹⁸ represents a linear or branched alkyl group having 1 to 12 carbon atoms or a linear or branched alkoxyl group having 1 to 12 carbon atoms. m and n each independently represent an integer of 0 to 3 (provided that m + n ≦ 5 is satisfied). ]
[3] (1) A step of forming a resist film using the radiation-sensitive resin composition according to [1] or [2],
(2) A pattern forming method comprising: exposing the obtained resist film using a KrF excimer laser, an ArF excimer laser, an electron beam (EB), or extreme ultraviolet (EUV).

  According to the radiation sensitive resin composition of the present invention, KrF excimer laser, ArF excimer laser, EUV and other (extreme) deep ultraviolet rays, synchrotron radiation and other X-rays and electron beams are effectively sensitive to nano edge roughness, It is possible to form a negative resist film that is excellent in sensitivity and resolution and that can form a fine pattern with high accuracy and stability.

It is a typical top view at the time of seeing a line pattern from the upper part. It is typical sectional drawing of a line pattern shape.

  Hereinafter, the present invention will be described in detail. In the present specification, “(meth) acrylate” means “acrylate” or “methacrylate”.

[1] Radiation-sensitive resin composition The radiation-sensitive resin composition of the present invention is characterized by containing a specific (A) polymer and (B) a specific compound.
Therefore, according to this radiation-sensitive resin composition, in the lithography process, the KrF excimer laser, ArF excimer laser, EUV and other (extreme) far ultraviolet rays, synchrotron radiation and other X-rays and electron beams are effectively sensitive, A negative resist film that is excellent in nano edge roughness, sensitivity, and resolution and that can form a fine pattern with high accuracy and stability can be formed.

[1-1] (A) Polymer The polymer (hereinafter also referred to as “polymer (A)”) is an alkali-soluble polymer, and becomes alkali-insoluble or hardly soluble by the action of an acid. Yes, the side chain contains at least one of an oxetanyl group and an epoxy group and at least one of a carboxyl group and a phenolic hydroxyl group. Incidentally, at least one of the oxetanyl group and the epoxy group, and at least one of the carboxyl group and the phenolic hydroxyl group may be contained in different side chains or in the same side chain. Are contained in different side chains.

  In particular, the polymer (A) is represented by a repeating unit represented by the following general formula (1-a) [hereinafter referred to as “repeating unit (1-a)”] and a general formula (1-b) below. At least one of repeating units [hereinafter referred to as “repeating unit (1-b)”] and repeating units represented by the following general formulas (2) to (7) [hereinafter referred to as “repeating unit (2) to (7) ". It is preferable that it is a polymer containing at least 1 sort (s) of these.

〔一般式（１−ａ）において、Ｒ^１は水素原子又は炭素数１〜４のアルキル基を示す。Ｒ^２は水素原子又は炭素数１〜４のアルキル基を示す。Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は、それぞれ独立に、水素原子、フッ素原子、炭素数１〜４のアルキル基、フェニル基、又は炭素数１〜４のパーフルオロアルキル基を示す。ｎは１〜６の整数である。〕

[In General Formula (1-a), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ³ , R ⁴ , R ⁵ and R ⁶ each independently represent a hydrogen atom, a fluorine atom, an alkyl group having 1 to 4 carbon atoms, a phenyl group, or a perfluoroalkyl group having 1 to 4 carbon atoms. n is an integer of 1-6. ]

〔一般式（１−ｂ）において、Ｒ^１は水素原子又は炭素数１〜４のアルキル基を示す。Ｒ^２は水素原子又は炭素数１〜４のアルキル基を示す。ｎは１〜６の整数である。〕

[In General Formula (1-b), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is an integer of 1-6. ]

〔一般式（２）において、Ｒ^７は水素原子又はメチル基を示す。Ｒ^８及びＲ^９は、それぞれ独立に、メチレン基、炭素数２〜６の直鎖状若しくは分岐状のアルキレン基、又は炭素数４〜１２の脂環式のアルキレン基を示す。〕

[In General Formula (2), R ⁷ represents a hydrogen atom or a methyl group. R ⁸ and R ⁹ each independently represent a methylene group, a linear or branched alkylene group having 2 to 6 carbon atoms, or an alicyclic alkylene group having 4 to 12 carbon atoms. ]

〔一般式（３）において、Ｒ^１０は水素原子又はメチル基を示す。Ｒ^１１はメチレン基、炭素数２〜６の直鎖状若しくは分岐状のアルキレン基、又は炭素数４〜１２の脂環式のアルキレン基を示す。〕

[In General Formula (3), R ¹⁰ represents a hydrogen atom or a methyl group. R ¹¹ represents a methylene group, a linear or branched alkylene group having 2 to 6 carbon atoms, or an alicyclic alkylene group having 4 to 12 carbon atoms. ]

〔一般式（４）において、Ｒ^１２は水素原子又はメチル基を示す。〕

In [Formula ^{(4), R 12} represents a hydrogen atom or a methyl group. ]

〔一般式（５）において、Ｒ^１３は水素原子又はメチル基を示す。Ｒ^１４は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシル基を示す。ｉ及びｊは、それぞれ独立に、０〜３の整数を示す（但し、ｉ＋ｊ≦５を満たす。）。〕

[In General Formula (5), R ¹³ represents a hydrogen atom or a methyl group. R ¹⁴ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxyl group having 1 to 12 carbon atoms. i and j each independently represent an integer of 0 to 3 (provided that i + j ≦ 5 is satisfied). ]

〔一般式（６）において、Ｒ^１５は水素原子又はメチル基を示す。Ｒ^１６は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシル基を示す。ｋ及びｌは、それぞれ独立に、０〜３の整数を示す（但し、ｋ＋ｌ≦５を満たす。）。〕

In [Formula ^{(6), R 15} represents a hydrogen atom or a methyl group. R ¹⁶ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxyl group having 1 to 12 carbon atoms. k and l each independently represent an integer of 0 to 3 (provided that k + l ≦ 5 is satisfied). ]

〔一般式（７）において、Ｒ^１７は水素原子又はメチル基を示す。Ｒ^１８は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシル基を示す。ｍ及びｎは、それぞれ独立に、０〜３の整数を示す（但し、ｍ＋ｎ≦５を満たす。）。〕

[In General Formula (7), R ¹⁷ represents a hydrogen atom or a methyl group. R ¹⁸ represents a linear or branched alkyl group having 1 to 12 carbon atoms or a linear or branched alkoxyl group having 1 to 12 carbon atoms. m and n each independently represent an integer of 0 to 3 (provided that m + n ≦ 5 is satisfied). ]

Examples of the alkyl group having 1 to 4 carbon atoms in R ^{1 to} R ⁶ of the general formula (1-a) include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, 2- A methylpropyl group, a 1-methylpropyl group, a t-butyl group, etc. are mentioned.
Examples of the perfluoroalkyl group having 1 to 4 carbon atoms in R ^{3 to} R ⁶ of the general formula (1-a) include, for example, that all the hydrogen atoms in the above alkyl group having 1 to 4 carbon atoms are substituted with fluorine atoms. Can be mentioned.

In general formula (1-a), R ¹ is preferably a hydrogen atom or a methyl group.
R ² is preferably a hydrogen atom, a methyl group or an ethyl group, more preferably a methyl group or an ethyl group.
Furthermore, R ^{3 to} R ⁶ are each preferably a hydrogen atom, a fluorine atom, a methyl group or an ethyl group, and more preferably a hydrogen atom.
Further, n is preferably 1 or 2, more preferably 1.

  Examples of the monomer that gives the repeating unit (1-a) include 3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, and 3- (methacryloyloxymethyl) -3-. Methyloxetane, 3- (methacryloyloxymethyl) -2-methyloxetane, 3- (methacryloyloxymethyl) -2-trifluoromethyloxetane, 3- (methacryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (methacryloyl) Oxymethyl) -2-phenyloxetane, 3- (methacryloyloxymethyl) -2,2-difluorooxetane, 3- (methacryloyloxymethyl) -2,2,4-trifluorooxetane, 3- (methacryloyloxymethyl) -2,2,4,4-tet Fluoroxetane, 3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -3-ethyloxetane, 2-ethyl-3- (methacryloyloxyethyl) oxetane, 3- (methacryloyloxyethyl) -2-trifluoro Methyl oxetane, 3- (methacryloyloxyethyl) -2-pentafluoroethyl oxetane, 3- (methacryloyloxyethyl) -2-phenyloxetane, 2,2-difluoro-3- (methacryloyloxyethyl) oxetane, 3- (methacryloyl) Methacrylic acid esters such as (oxyethyl) -2,2,4-trifluorooxetane, 3- (methacryloyloxyethyl) -2,2,4,4-tetrafluorooxetane;

3- (acryloyloxymethyl) oxetane, 3- (acryloyloxymethyl) -3-ethyloxetane, 3- (acryloyloxymethyl) -3-methyloxetane, 3- (acryloyloxymethyl) -2-methyloxetane, 3- (Acryloyloxymethyl) -2-trifluoromethyloxetane, 3- (acryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (acryloyloxymethyl) -2-phenyloxetane, 3- (acryloyloxymethyl) -2 , 2-Difluorooxetane, 3- (acryloyloxymethyl) -2,2,4-trifluorooxetane, 3- (acryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (acryloyloxy) Ethyl) oxetane, 3- (acrylo Ruoxyethyl) -3-ethyloxetane, 2-ethyl-3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -2-trifluoromethyloxetane, 3- (acryloyloxyethyl) -2-pentafluoroethyloxetane 3- (acryloyloxyethyl) -2-phenyloxetane, 2,2-difluoro-3- (acryloyloxyethyl) oxetane, 3- (acryloyloxyethyl) -2,2,4-trifluorooxetane, 3- ( Acrylic acid esters such as (acryloyloxyethyl) -2,2,4,4-tetrafluorooxetane.
Among these monomers, compounds having structures represented by the following general formulas (1-a-1) to (1-a-4) are preferable.

  In addition, when the repeating unit (1-a) is contained in the polymer (A), this repeating unit (1-a) may be contained in only one kind, or may be contained in two or more kinds. Good.

^{R 1} and ^{R 2} in the general formula (1-b), respectively, have the same meanings as ^{R 1} and ^{R 2} in the above general formula (1-a), it can be directly applied to the corresponding sections.

  Examples of the monomer that gives the repeating unit (1-b) include glycidyl (meth) acrylate, (meth) acrylic acid-β-methylglycidyl, (meth) acrylic acid-β-ethylglycidyl, (meth) Acrylic acid-β-propylglycidyl, α-ethylacrylic acid-β-methylglycidyl, (meth) acrylic acid-3-methyl-3,4-epoxybutyl, (meth) acrylic acid-3-ethyl-3,4- Examples thereof include epoxybutyl, (meth) acrylic acid-4-methyl-4,5-epoxypentyl, (meth) acrylic acid-5-methyl-5,6-epoxyhexyl, and the like.

  Among these monomers, compounds having structures represented by the following general formulas (1-b-1) to (1-b-4) are preferable.

  In addition, when the repeating unit (1-b) is contained in the polymer (A), this repeating unit (1-b) may be contained only in one kind, or may be contained in two or more kinds. Good.

Examples of the linear or branched alkylene group having 2 to 6 carbon atoms in R ⁸ and R ⁹ in the general formula (2) include, for example, ethylene group; 1,3-propylene group or 1,2-propylene group A propylene group such as tetramethylene group, pentamethylene group, hexamethylene group, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, 2-methyl-1,2-propylene group, 1 Examples thereof include saturated chain hydrocarbon groups such as -methyl-1,4-butylene group, 2-methyl-1,4-butylene group, methylidene group, ethylidene group, propylidene group, and 2-propylidene group.

As a C4-C12 alicyclic alkylene group in R < ⁸ > and R < ⁹ > of General formula (2), a monocyclic hydrocarbon cyclic group, a bridged cyclic hydrocarbon cyclic group, etc. are mentioned, for example.
Examples of the monocyclic hydrocarbon ring group include a cyclobutylene group such as a 1,3-cyclobutylene group, a cyclopentylene group such as a 1,3-cyclopentylene group, and a cyclohexene group such as a 1,4-cyclohexylene group. Examples thereof include cycloalkylene groups having 4 to 12 carbon atoms such as a silylene group and a cyclooctylene group such as a 1,5-cyclooctylene group.
Examples of the bridged cyclic hydrocarbon ring group include a norbornylene group such as a 1,4-norbornylene group or a 2,5-norbornylene group, an adamantylene group such as a 1,5-adamantylene group, and a 2,6-adamantylene group. 2-4 cyclic hydrocarbon ring groups having 4 to 12 carbon atoms, and the like.

In the general formula (2), R ⁸ and R ⁹ may be the same group or different from each other.

  As a monomer which gives the repeating unit (2) represented by the general formula (2), for example, 2-methacryloyloxyethyl hexahydrophthalate, 3-methacryloyloxypropyl hexahydrophthalate, 4-hexahydrophthalic acid 4- And methacryloyloxybutyl.

  In addition, when the repeating unit (2) is contained in the polymer (A), this repeating unit (2) may be contained only 1 type, and may be contained 2 or more types.

The “linear or branched alkylene group having 2 to 6 carbon atoms” and the “alicyclic alkylene group having 4 to 12 carbon atoms” in R ¹¹ of the general formula (3) are each represented by the general formula ( The description of “a linear or branched alkylene group having 2 to 6 carbon atoms” and “an alicyclic alkylene group having 4 to 12 carbon atoms” in R ⁸ of 2) can be applied as it is.

  Examples of the monomer that gives the repeating unit (3) represented by the general formula (3) include cyclohexacarboxylic acid 2-methacryloyloxy, propylcarboxylic acid 3-methacryloyloxy, and the like.

  In addition, when the repeating unit (3) is contained in the polymer (A), this repeating unit (3) may be contained only 1 type, and may be contained 2 or more types.

Examples of the monomer giving the repeating unit (4) represented by the general formula (4) include acrylic acid and methacrylic acid.
In addition, when the repeating unit (4) is contained in the polymer (A), this repeating unit (4) may be contained only 1 type, and may be contained 2 or more types.

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms in R ¹⁴ of the general formula (5) include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, and an n-butyl group. , 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.
Examples of the linear or branched alkoxyl group having 1 to 12 carbon atoms in R ¹⁴ include methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group. Group, 1-methylpropoxy group, t-butoxy group and the like.
Among these, R ¹⁴ is preferably a methyl group, an ethyl group, an n-butyl group, or a t-butyl group.
In the case where R ¹⁴ there are a plurality (i.e., when j in formula is 2 or 3), respectively, may be the same group or may be different groups.

  In the general formula (5), i is an integer of 0 to 3, and is more preferably 1 or 2. Moreover, j is an integer of 0-3, and it is more preferable that it is an integer of 0-2.

Specific examples of the repeating unit (5) represented by the general formula (5) include repeating units represented by the following formulas (5-1) to (5-4).
In addition, when the repeating unit (5) is contained in the polymer (A), this repeating unit (5) may be contained only 1 type, and may be contained 2 or more types.

With respect to the alkyl group and alkoxyl group of R ¹⁶ in the general formula (6), the explanations regarding the alkyl group and alkoxyl group of R ¹⁴ in the general formula (5) can be applied as they are.
When a plurality of R ¹⁶ are present (that is, when 1 in the formula is 2 or 3), they may be the same group or different groups.

  In General formula (6), k is an integer of 0-3, and it is more preferable that it is 1 or 2. L is an integer of 0 to 3, and is more preferably 0 or 1.

Specific examples of the repeating unit (6) represented by the general formula (6) include repeating units represented by the following formulas (6-1) and (6-2).
In addition, when the repeating unit (6) is contained in the polymer (A), this repeating unit (6) may be contained only 1 type, and may be contained 2 or more types.

Regarding the alkyl group and alkoxyl group of R ¹⁸ in the general formula (7), the description regarding the alkyl group and alkoxyl group of R ¹⁴ in the general formula (5) can be applied as it is.
In the case where R ¹⁸ there are a plurality (i.e., when n in the formula is 2 or 3), respectively, may be the same group or may be different groups.

  In General formula (7), m is an integer of 0-3, and it is more preferable that it is 1 or 2. N is an integer of 0 to 3, more preferably 0 or 1.

Specific examples of the repeating unit (7) represented by the general formula (7) include repeating units represented by the following formulas (7-1) and (7-2).
In addition, when the repeating unit (7) is contained in the polymer (A), this repeating unit (7) may be contained only 1 type, and may be contained 2 or more types.

Each repeating unit represented by the formulas (5-1) to (5-3) can be obtained by using a corresponding hydroxystyrene derivative as a monomer. Furthermore, it can also obtain by using as a monomer the compound from which a hydroxy styrene derivative is obtained by hydrolyzing.
As a monomer used in order to produce | generate each repeating unit represented by Formula (5-1)-(5-3), p-acetoxy styrene, p- (1-ethoxyethoxy) styrene, etc. are preferable. When these monomers are used, each repeating unit represented by the formulas (5-1) to (5-3) may be generated by a side chain hydrolysis reaction after forming a polymer. it can.

In addition, each repeating unit represented by the formulas (5-4), (6-1), (6-2), (7-1), and (7-2) uses a corresponding monomer. Can be obtained.
As a monomer used to generate each repeating unit represented by the formula (5-4), (6-1), (6-2), (7-1) and (7-2), P-isopropenylphenol, 4-hydroxyphenyl acrylate, 4-hydroxyphenyl methacrylate, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide and the like are preferable.

In addition to the repeating units (1-a), (1-b) and (2) to (7), the polymer (A) is a repeating unit derived from a non-acid dissociable compound (hereinafter referred to as “repeating unit”). (8) ") may be further included.
Non-acid dissociable compounds include, for example, styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, isobornyl acrylate, tricyclodecanyl (meth) acrylate, and tetracyclodode. Examples include senyl (meth) acrylate and compounds represented by the following formula (b-1). Among these, styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, tricyclodecanyl acrylate, and a compound represented by the following formula (b-1) are preferable.
In addition, when the repeating unit (8) is contained in the polymer (A), this repeating unit (8) may be contained only 1 type, and may be contained 2 or more types.

  The total content of the repeating units (1-a) and (1-b) in the polymer (A) is 1 mol% or more when the total of all the repeating units in the polymer (A) is 100 mol%. More preferably, it is 30-90 mol%, More preferably, it is 40-80 mol%. When this content is 1 mol% or more, when the polymer (A) is used as an alkali-soluble polymer in the radiation-sensitive resin composition, it can be excellent in nano edge roughness.

  The total content of the repeating units (2) to (7) is preferably 90 mol% or less, more preferably when the total of all repeating units in the polymer (A) is 100 mol%. Is 10 to 90 mol%, more preferably 20 to 90 mol%, particularly preferably 20 to 80 mol%. When the total content is 90 mol% or less, when the polymer (A) is used as the alkali-soluble polymer in the radiation-sensitive resin composition, it can be excellent in nano edge roughness. .

  Furthermore, the total content of the repeating units (1-a), (1-b) and (2) to (7) is, when the total of all repeating units in the polymer (A) is 100 mol%, It is preferable that it is 20 mol% or more, More preferably, it is 30-100 mol%, More preferably, it is 40-100 mol%. When the total content is 20 mol% or more, when the polymer (A) is used as an alkali-soluble polymer in the radiation-sensitive resin composition, it can be excellent in nano edge roughness. .

  The content of the repeating unit (8) is preferably 60 mol% or less, more preferably 0 to 50 mol%, when the total of all repeating units in the polymer (A) is 100 mol%. It is. When the content is 60 mol% or less, when the polymer (A) is used as an alkali-soluble polymer in the radiation-sensitive resin composition, the performance balance between resolution performance and nanoedge roughness is excellent. Can be.

  In addition, the radiation sensitive resin composition of this invention may contain only 1 type of polymers (A), and may contain 2 or more types.

  The method for synthesizing the polymer (A) in the present invention is not particularly limited, and can be obtained, for example, by known radical polymerization or anionic polymerization. Further, the side chain hydroxystyrene unit in the above repeating units (5) to (7) is a base or a polymer obtained by radical polymerization or anion polymerization (hereinafter referred to as polymer (Ia)) in an organic solvent. It can be obtained by hydrolysis of an acetoxy group or the like in the presence of an acid.

  In the radical polymerization, for example, 3- (methacryloyloxymethyl) -3 which gives repeating units (1-a) and (1-b) in the presence of a radical polymerization initiator in a suitable organic solvent under a nitrogen atmosphere. -Necessary monomers such as ethyl oxetane and glycidyl methacrylate can be stirred and heated.

Examples of the radical polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobis- (4-methoxy-). 2,4-dimethylvaleronitrile) 2,2′-azobismethylbutyronitrile, 2,2′-azobiscyclohexanecarbonitrile, cyanomethylethylazoformamide, 2,2′-azobis (2,4-dimethylpropion) Acid methyl), azo compounds such as 2,2′-azobiscyanovaleric acid; benzoyl peroxide, lauroyl peroxide, 1,1′-bis- (t-butylperoxy) cyclohexane, 3,5,5-trimethylhexa Examples thereof include organic peroxides such as noyl peroxide and t-butylperoxy-2-ethylhexanoate, and hydrogen peroxide.
In this polymerization, a polymerization aid such as 2,2,6,6-tetramethyl-1-piperidinyloxy, iodine, mercaptan, styrene dimer may be added as necessary.

The reaction temperature in radical polymerization is not particularly limited, and is appropriately selected depending on the type of initiator and the like (for example, 50 to 200 ° C.). In particular, when an azo initiator or a peroxide initiator is used, a temperature at which the half life of the initiator is about 10 minutes to about 30 hours is preferable, and more preferably, the half life of the initiator is about 30 minutes to about 10 hours. Temperature.
The reaction time varies depending on the type of initiator and the reaction temperature, but the reaction time during which 50% or more of the initiator is consumed is desirable, and in many cases is about 0.5 to 24 hours.

  Anionic polymerization is, for example, 3- (methacryloyloxymethyl) which gives repeating units (1-a) and (1-b) in the presence of an anionic polymerization initiator in a suitable organic solvent under a nitrogen atmosphere. Necessary monomers such as -3-ethyloxetane and glycidyl methacrylate are stirred and maintained at a predetermined temperature.

  Examples of the anionic polymerization initiator include n-butyl lithium, s-butyl lithium, t-butyl lithium, ethyl lithium, ethyl sodium, 1,1-diphenylhexyl lithium, 1,1-diphenyl-3-methylpentyl lithium, and the like. The organic alkali metal is mentioned.

The reaction temperature in the anionic polymerization is not particularly limited and is appropriately selected depending on the kind of the initiator. In particular, when alkyl lithium is used as an initiator, the temperature is preferably −100 to 50 ° C., more preferably −78 to 30 ° C.
The reaction time varies depending on the type of initiator and the reaction temperature, but the reaction time during which 50% or more of the initiator is consumed is desirable, and in many cases is about 0.5 to 24 hours.

  In the synthesis of the polymer (A), it is possible to carry out the polymerization reaction by heating without using a polymerization initiator.

In addition, when a hydroxystyrene unit is introduced by hydrolyzing the side chain of the polymer (Ia), examples of the acid used for the hydrolysis reaction include p-toluenesulfonic acid and its hydrate, methane Organic acids such as sulfonic acid, trifluoromethanesulfonic acid, malonic acid, oxalic acid, 1,1,1-fluoroacetic acid; inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid, hydrobromic acid; or pyridinium p-toluenesulfonate, ammonium Examples thereof include salts such as p-toluenesulfonate and 4-methylpyridinium p-toluenesulfonate.
Furthermore, examples of the base include inorganic bases such as potassium hydroxide, sodium hydroxide, sodium carbonate, and potassium carbonate; organic bases such as triethylamine, N-methyl-2-pyrrolidone, piperidine, and tetramethylammonium hydroxide.

Examples of the organic solvent used for the polymerization and hydrolysis described above include ketones such as acetone, methyl ethyl ketone, and methyl amyl ketone; ethers such as diethyl ether and tetrahydrofuran (THF); methanol, ethanol, propanol, and the like. Alcohols; aliphatic hydrocarbons such as hexane, heptane, and octane; aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated alkyls such as chloroform, bromoform, methylene chloride, methylene bromide, and carbon tetrachloride; Esters such as ethyl acetate, butyl acetate, ethyl lactate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cellosolves; non-dimethylformamide, dimethyl sulfoxide, hexamethylphosphoramide, etc. Protic polar solvents, and the like.
Among these, acetone, methyl amyl ketone, methyl ethyl ketone, tetrahydrofuran, methanol, ethanol, propanol, ethyl acetate, butyl acetate, ethyl lactate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate and the like are preferable.

The polystyrene equivalent weight average molecular weight (hereinafter also referred to as “Mw”) of the polymer (A) measured by gel permeation chromatography (GPC) is preferably 2000-100000, more preferably 2000-40000, More preferably, it is 2000-25000.
Further, the ratio (Mw / Mn) of Mw of the polymer (A) to polystyrene-reduced number average molecular weight (hereinafter also referred to as “Mn”) measured by GPC is usually 1 to 5, more preferably 1 To 3, more preferably 1 to 2.5.

[1-2] (B) Compound The radiation-sensitive resin composition of the present invention, together with the polymer (A) described above, is a compound represented by the following general formula (b1) or (b2) (hereinafter referred to as “compound ( B) ").
This compound (B) is a substance that generates an acid in the radiation-sensitive resin composition by irradiation of the radiation-sensitive resin composition of the present invention with an electron beam or radiation in a lithography process. And the bridge | crosslinking in a polymer (A) arises by the effect | action of the acid generate | occur | produced from this compound (B).

〔一般式（ｂ１）及び（ｂ２）において、Ｒ^３１〜Ｒ^３５は、それぞれ独立に、水素原子、フッ素原子、トリフルオロメチル基、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、炭素数５〜２５のシクロアルキル基、−Ｓ−Ｒ^３６基、−Ｏ−ＳＯ_２−Ｒ^３７基、又は、−ＳＯ_２−Ｒ^３８基を示す（但し、Ｒ^３６〜Ｒ^３８は、それぞれ独立に、フッ素原子で置換若しくは非置換の炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、フッ素原子で置換若しくは非置換の炭素数５〜２５のシクロアルキル基、フッ素原子で置換若しくは非置換の炭素数６〜２２のアリール基を示す。）。Ｘ_１ ⁻及びＸ_２ ⁻は、それぞれ独立に、ＯＨ⁻、Ｒ^３９Ｏ⁻、又は、Ｒ^４０ＣＯＯ⁻を示す（但し、Ｒ^３９及びＲ^４０は、それぞれ独立に、フッ素原子で置換若しくは非置換の炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、フッ素原子で置換若しくは非置換の炭素数５〜２５のシクロアルキル基、又は、フッ素原子、トリフルオロメチル基、及びヒドロキシル基のうちの少なくとも１種で置換若しくは非置換の炭素数６〜２２のアリール基を示す。）。〕

[In General Formulas (b1) and (b2), R ^{31 to} R ³⁵ are each independently a hydrogen atom, a fluorine atom, a trifluoromethyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, A cycloalkyl group having 5 to 25 carbon atoms, -S-R ³⁶ group, -O-SO ₂ -R ³⁷ group, or -SO ₂ -R ³⁸ group (provided that R ^{36 to} R ³⁸ are each independently A linear or branched alkyl group having 1 to 12 carbon atoms substituted or unsubstituted with a fluorine atom, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted with a fluorine atom, or substituted or non-substituted with a fluorine atom. A substituted aryl group having 6 to 22 carbon atoms is shown.). X ₁ ^- and _{X 2} ^- are each ^{independently, OH -, R 39 O -} , ^or, R 40 COO ^- showing the ^{(where, R 39} and ^{R 40} each independently represent a substituted or unsubstituted with fluorine atom A linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted by a fluorine atom, or a fluorine atom, a trifluoromethyl group, and a hydroxyl group. And a substituted or unsubstituted aryl group having 6 to 22 carbon atoms. ]

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms in R ^{31 to} R ³⁵ of the general formulas (b1) and (b2) include a methyl group, an ethyl group, an n-propyl group, and i-propyl. Group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.
^Further, the cycloalkyl group of 5 to 25 carbon atoms in R 31 ^{to R 35,} for example, a cyclopentyl group, a cyclohexyl group, cyclooctyl group, adamantyl group, etc. norbornyl group.

R ^{36 to} R ³⁸ unsubstituted C 1-12 linear or branched alkyl in the —S—R ³⁶ group, —O—SO ₂ —R ³⁷ group, and —SO ₂ —R ³⁸ group. Examples of the group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a 2-methylpropyl group, a 1-methylpropyl group, and a t-butyl group.
Examples of the linear or branched alkyl group of R ³⁶ to R ³⁸ having 1 to 12 carbon atoms substituted with fluorine atoms, at least one or more of the unsubstituted alkyl group having 1 to 12 carbon atoms described above And a group in which a hydrogen atom is substituted with a fluorine atom.

Examples of the unsubstituted cycloalkyl group having 5 to 25 carbon atoms of R ^{36 to} R ³⁸ include a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, an adamantyl group, and a norbornyl group.
As the cycloalkyl group has been 5 to 25 carbon atoms substituted with a fluorine atom R ³⁶ to R ^38, at least one or more hydrogen atoms in the unsubstituted cycloalkyl group having 5 to 25 carbon atoms described above fluorine Mention may be made of groups substituted by atoms.

Examples of the unsubstituted aryl group having 6 to 22 carbon atoms of R ^{36 to} R ³⁸ include a phenyl group, a tolyl group, a naphthyl group, and an anthryl group.
The aryl group R ³⁶ to R ³⁸ fluorine atoms are replaced by an atom having 6 to 22, at least one hydrogen atom in the unsubstituted aryl group having 6 to 22 carbon atoms described above with a fluorine atom Mention may be made of substituted groups.

R ³⁹ and R ⁴⁰ in “X ₁ ^— of the general formula (b1) and X ₂ ^— of the general formula (b2)” are linear or branched alkyl having 1 to 12 carbon atoms substituted or unsubstituted by a fluorine atom. Group "," cycloalkyl group substituted or unsubstituted with 5 to 25 carbon atoms "and" unsubstituted aryl group with 6 to 22 carbon atoms "are represented by the general formulas (b1) and (b2), respectively. ) In R ^{31 to} R ³⁵ , “a linear or branched alkyl group having 1 to 12 carbon atoms that is substituted or unsubstituted by a fluorine atom”, “cyclocarbon having 5 to 25 carbon atoms that is substituted or unsubstituted by a fluorine atom” The descriptions of “alkyl group” and “unsubstituted aryl group having 6 to 22 carbon atoms” can be applied as they are.

  Moreover, as a C6-C22 aryl group substituted by at least 1 sort (s) of a fluorine atom, a trifluoromethyl group, and a hydroxyl group, at least 1 in the above-mentioned unsubstituted C6-C22 aryl group is mentioned. Mention may be made of groups in which one or more hydrogen atoms have been replaced by fluorine atoms.

  As the cation in the compound represented by the general formula (b1), cations represented by the following formulas (x1-1) to (x1-3) are preferable.

  As the cation in the compound represented by the general formula (b2), cations represented by the following formulas (x2-1) to (x2-2) are preferable.

In addition, X ₁ ⁻ and X ₂ ⁻ in the compound (B) are OH ⁻ , CH ₃ COO ⁻ , and anions represented by the following formulas (Z-1) to (Z-4), respectively. Is preferred.

As a specific compound (B), for example, the cation moiety is a cation represented by the formula (x1-1), and the anion moiety is OH ⁻ , CH ₃ COO ⁻ , and the formula (Z-2). Or what is an anion represented by (Z-3) etc. are mentioned.

  In addition, the radiation sensitive resin composition of this invention may contain only 1 type of compounds (B), and may contain 2 or more types.

  The content of the compound (B) is preferably 15 parts by mass or less, more preferably 0.001 to 10 parts by mass, and still more preferably 0.005 when the polymer (A) is 100 parts by mass. -5 parts by mass. The content of 15 parts by mass or less is preferable because the sensitivity of the formed resist film and the developability of the exposed part are excellent. In addition, when this content exceeds 15 mass parts, there exists a possibility that the sensitivity of the formed resist film and the developability of an exposure part may fall. Further, if the content is less than 0.001 part by mass, the pattern shape and dimensional fidelity of the formed resist film may be lowered depending on the process conditions.

[1-3] (C) Solvent The radiation-sensitive resin composition of the present invention is preferably obtained by dissolving each component such as the polymer (A) and the compound (B) in a solvent. That is, it is preferable to further contain a solvent (hereinafter also referred to as solvent (C)).
Examples of the solvent (C) include linear or branched ketones, cyclic ketones, propylene glycol monoalkyl ether acetates, alkyl 2-hydroxypropionate, alkyl 3-alkoxypropionate, and γ- It is preferably at least one selected from the group consisting of butyrolactone and the like.

  The blending amount of the solvent (C) in the radiation-sensitive resin composition of the present invention is preferably such that the total solid concentration in the composition is 70% by mass or less, more preferably 1 to 70% by mass. The amount is more preferably 1 to 15% by mass, particularly preferably 1 to 10% by mass.

  And the radiation sensitive resin composition of this invention prepares the above-mentioned polymer (A) and the other component mentioned later by melt | dissolving uniformly in a solvent so that total solid content concentration may become the above-mentioned range. be able to. In addition, after preparing in this way, it is preferable to filter with a filter with a pore diameter of about 0.2 μm, for example.

[1-4] (D) Radiation-sensitive acid generator The radiation-sensitive acid generator (hereinafter also referred to as “acid generator (D)”) is a radiation-sensitive resin composition of the present invention in a lithography process. It is a substance that generates an acid in the radiation-sensitive resin composition when irradiated with an electron beam or radiation. And the bridge | crosslinking in a polymer (A) arises by the effect | action of the acid generate | occur | produced from this acid generator (D).

As the acid generator (D), for example, at least one selected from the group consisting of an onium salt, a diazomethane compound, and a sulfonimide compound is used from the viewpoint of good acid generation efficiency, heat resistance, and the like. preferable. In addition, the above-mentioned compound (B) shall not be contained in the acid generator (D) in this invention.
Moreover, these acid generators (D) may be used individually by 1 type, and may be used in combination of 2 or more type.

  Examples of the onium salt include compounds represented by the following general formulas (d1) and (d2).

〔一般式（ｄ１）及び（ｄ２）において、Ｒ^２１〜Ｒ^２５は、それぞれ独立に、水素原子、フッ素原子、トリフルオロメチル基、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、炭素数５〜２５のシクロアルキル基、−Ｓ−Ｒ^２６基、−Ｏ−ＳＯ_２−Ｒ^２７基、又は、−ＳＯ_２−Ｒ^２８基を示す（但し、Ｒ^２６〜Ｒ^２８は、それぞれ独立に、フッ素原子で置換若しくは非置換の炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、フッ素原子で置換若しくは非置換の炭素数５〜２５のシクロアルキル基、フッ素原子で置換若しくは非置換の炭素数６〜２２のアリール基を示す。）。Ｘ_３ ⁻及びＸ_４ ⁻は、それぞれ独立に、下記一般式（ｘ２−１）〜（ｘ２−４）で表されるアニオンのいずれかを示す。〕

[In General Formulas (d1) and (d2), R ^{21 to} R ²⁵ are each independently a hydrogen atom, a fluorine atom, a trifluoromethyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, A cycloalkyl group having 5 to 25 carbon atoms, —S—R ²⁶ group, —O—SO ₂ —R ²⁷ group, or —SO ₂ —R ²⁸ group (provided that R ^{26 to} R ²⁸ are each independently A linear or branched alkyl group having 1 to 12 carbon atoms substituted or unsubstituted with a fluorine atom, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted with a fluorine atom, or substituted or non-substituted with a fluorine atom. A substituted aryl group having 6 to 22 carbon atoms is shown.). X ₃ ⁻ and X ₄ ⁻ each independently represents any one of the anions represented by the following general formulas (x2-1) to (x2-4). ]

〔一般式（ｘ２−１）において、Ｒ^４１及びＲ^４２は、相互に独立に、少なくとも１つのフッ素原子で置換された炭素数１〜２０のアルキル基を示すか、或いは、Ｒ^４１及びＲ^４２が相互に結合して、少なくとも１つのフッ素原子で置換された炭素数１〜２０の環状構造を形成する。また、一般式（ｘ２−２）において、Ｒ^４３、Ｒ^４４及びＲ^４５は、相互に独立に、少なくとも１つのフッ素原子で置換された炭素数１〜２０のアルキル基を示すか、或いは、Ｒ^４３、Ｒ^４４及びＲ^４５のうちのいずれか２つが相互に結合して、少なくとも１つのフッ素原子で置換された炭素数３〜２０の環状構造を形成しており、且つ残りの１つが、少なくとも１つのフッ素原子で置換された炭素数１〜２０のアルキル基を示す。〕

[In General Formula (x2-1), R ⁴¹ and R ⁴² each independently represent an alkyl group having 1 to 20 carbon atoms substituted with at least one fluorine atom, or R ⁴¹ and R ^42. Are bonded to each other to form a C1-C20 cyclic structure substituted with at least one fluorine atom. In the general formula (x2-2), R ⁴³ , R ⁴⁴ and R ⁴⁵ each independently represent an alkyl group having 1 to 20 carbon atoms substituted with at least one fluorine atom, or R Any one of ⁴³ , R ⁴⁴ and R ⁴⁵ are bonded to each other to form a cyclic structure having 3 to 20 carbon atoms substituted with at least one fluorine atom, and the remaining one is at least An alkyl group having 1 to 20 carbon atoms substituted with one fluorine atom is shown. ]

〔一般式（ｘ２−３）において、Ｒ^４６は、フッ素原子又は置換されていてもよい炭素数１〜１２の炭化水素基を示す。ｎは、１〜１０の整数を示す。また、一般式（ｘ２−４）において、Ｒ^４７は、フッ素原子又は置換されていてもよい炭素数１〜１２の炭化水素基を示す。〕

[In General Formula (x2-3), R ⁴⁶ represents a fluorine atom or an optionally substituted hydrocarbon group having 1 to 12 carbon atoms. n represents an integer of 1 to 10. In the general formula (x2-4), R ⁴⁷ represents a fluorine atom or an optionally substituted hydrocarbon group having 1 to 12 carbon atoms. ]

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms in R ^{21 to} R ²⁵ in the general formulas (d1) and (d2) include a methyl group, an ethyl group, an n-propyl group, and i-propyl. Group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.
^Further, the cycloalkyl group of 5 to 25 carbon atoms in R 21 ^{to R 25,} for example, a cyclopentyl group, a cyclohexyl group, cyclooctyl group, adamantyl group, etc. norbornyl group.

R ^{26 to} R ²⁸ unsubstituted C 1-12 linear or branched alkyl in the —S—R ²⁶ group, —O—SO ₂ —R ²⁷ group, and —SO ₂ —R ²⁸ group. Examples of the group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a 2-methylpropyl group, a 1-methylpropyl group, and a t-butyl group.
Examples of the linear or branched alkyl group having 1 to 12 carbon atoms which is substituted with a fluorine atom R ²⁶ to R ^28, at least one or more of the unsubstituted alkyl group having 1 to 12 carbon atoms described above And a group in which a hydrogen atom is substituted with a fluorine atom.

Examples of the unsubstituted cycloalkyl group having 5 to 25 carbon atoms of R ^{26 to} R ²⁸ include a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, an adamantyl group, and a norbornyl group.
As the cycloalkyl group has been 5 to 25 carbon atoms substituted with a fluorine atom R ²⁶ to R ^28, at least one or more hydrogen atoms in the unsubstituted cycloalkyl group having 5 to 25 carbon atoms described above fluorine Mention may be made of groups substituted by atoms.

Examples of the unsubstituted aryl group having 6 to 22 carbon atoms of R ^{26 to} R ²⁸ include a phenyl group, a tolyl group, a naphthyl group, and an anthryl group.
The aryl group R ²⁶ carbon atoms substituted with fluorine atoms to R ²⁸ 6 to 22, at least one hydrogen atom in the unsubstituted aryl group having 6 to 22 carbon atoms described above with a fluorine atom Mention may be made of substituted groups.

Examples of the alkyl group having 1 to 20 carbon atoms substituted with a fluorine atom in R ^{41 to} R ⁴⁵ in the general formulas (x2-1) and (x2-2) include, for example, a methyl group, an ethyl group, and an n-propyl group. , I-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like in which one or two or more hydrogen atoms are substituted with fluorine atoms. It is done. Specific examples include a trifluoromethyl group, a difluoroethyl group, and a nanofluorobutyl group.

  In the general formulas (x2-1) and (x2-2), as the cyclic structure having 3 to 20 carbon atoms substituted with at least one fluorine atom, one or more hydrogen atoms are substituted with fluorine atoms. And a structure containing a skeleton derived from an alkylene group having 3 to 20 carbon atoms.

Examples of the optionally substituted hydrocarbon group having 1 to 12 carbon atoms in R ⁴⁶ and R ⁴⁷ in the general formulas (x2-3) and (x2-4) include a methyl group, an ethyl group, and n-propyl. Group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.
Examples of the substituent include a nitro group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group, hydroxyl group, amino group, cyano group, alkoxyl group (preferably having 1 to 5 carbon atoms). ), A cycloalkyl group (preferably 3 to 15 carbon atoms), an aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably 2 to 7 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms). ), An alkoxycarbonyloxy group (preferably having 2 to 7 carbon atoms), and the like.
N in the general formula (x2-3) is an integer of 1 to 10, preferably an integer of 1 to 6.

  Examples of the diazomethane compound include compounds represented by the following formula (d3).

〔一般式（ｄ３）において、Ｒ^５１及びＲ^５２は相互に独立に１価の基を示す。〕

[In General Formula (d3), R ⁵¹ and R ⁵² each independently represent a monovalent group. ]

Examples of the monovalent group of R ⁵¹ and R ⁵² in the general formula (d3) include an alkyl group, an aryl group, a halogen-substituted alkyl group, and a halogen-substituted aryl group.
As an alkyl group, a C1-C12 linear or branched alkyl group is mentioned, for example. Specific examples include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a 2-methylpropyl group, a 1-methylpropyl group, and a t-butyl group.
As an aryl group, a C6-C22 aryl group is mentioned, for example. Specifically, a phenyl group, a tolyl group, a naphthyl group, an anthryl group, etc. are mentioned.
Examples of the halogen-substituted alkyl group include groups in which at least one or more hydrogen atoms in the above-described alkyl group are substituted with a halogen (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.).
Examples of the halogen-substituted aryl group include groups in which at least one or more hydrogen atoms in the above-described aryl group are substituted with halogen (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.).

  Examples of the sulfonimide compound include compounds represented by the following formula (d4).

〔一般式（ｄ４）において、Ｖは２価の基を示す。Ｒ^５３は１価の基を示す。〕

[In General Formula (d4), V represents a divalent group. R ⁵³ represents a monovalent group. ]

Examples of the divalent group of V in the general formula (d4) include a methylene group, an alkylene group, an arylene group, and an alkoxylene group.
As an alkylene group, a C2-C12 linear or branched alkylene group is mentioned, for example. Specific examples include an ethylene group, a 1-methylethylene group, and an n-butylene group.
As an arylene group, a C6-C22 arylene group is mentioned, for example. Specific examples include a phenylene group, a naphthylene group, a methylphenylene group, an ethylphenylene group, a chlorophenylene group, a bromophenylene group, and a fluorophenylene group.
As an alkoxylene group, a C2-C12 linear or branched alkoxylene group is mentioned, for example. Specific examples include a methoxylene group, an ethoxylene group, a propoxyxylene group, and a butylenexylene group.

In addition, examples of the monovalent group of R ⁵³ in the general formula (d4) include an alkyl group, an aryl group, a halogen-substituted alkyl group, and a halogen-substituted aryl group. For these explanations, the explanations for the monovalent organic group represented by R ^{51 in} formula (d3) can be applied as they are.

  The content of the acid generator (D) is preferably 0.1 to 50 parts by mass, more preferably 0.5 to 50 parts by mass, when the polymer (A) is 100 parts by mass. . The content of 0.1 to 50 parts by mass is preferable because it is excellent in sensitivity, developability, transparency to radiation, pattern shape, heat resistance, and the like. In addition, when this content is less than 0.1 mass part, there exists a possibility that a sensitivity and developability may fall. On the other hand, when it exceeds 50 parts by mass, there is a possibility that transparency to radiation, pattern shape, heat resistance and the like may be lowered.

[1-5] Acid Diffusion Control Agent In addition to the polymer (A), the compound (B), the solvent (C) and the acid generator (D), the radiation sensitive resin composition of the present invention includes an acid. A diffusion control agent may further be contained.
This acid diffusion control agent is a component having an action of controlling the diffusion phenomenon in the resist film (resist film) of the acid generated from the acid generator (D) by exposure and suppressing undesirable chemical reaction in the non-exposed region. is there.
In the radiation sensitive resin composition of the present invention, by adding this acid diffusion controller, the storage stability of the resulting radiation sensitive resin composition can be improved, and the resolution of the resist film to be formed is improved. Can be sufficiently improved. Furthermore, it is possible to suppress a change in the line width of the resist pattern due to fluctuations in the holding time (PED) from the exposure to the heat treatment after the exposure, and a radiation-sensitive resin composition having extremely excellent process stability. Obtainable.

As such an acid diffusion controller, for example, a nitrogen-containing organic compound is preferably used.
Examples of the nitrogen-containing organic compound include a compound represented by the following general formula (8) (hereinafter referred to as “nitrogen-containing compound (i)”), a compound having two nitrogen atoms in the same molecule (hereinafter referred to as “containing“ Nitrogen compound (ii) "), polyamino compounds having 3 or more nitrogen atoms, polymers (hereinafter collectively referred to as" nitrogen-containing compounds (iii) "), and the like. Furthermore, amide group-containing compounds, urea compounds, nitrogen-containing heterocyclic compounds, etc., excluding these nitrogen-containing compounds (i) to (iii) can be mentioned.

〔一般式（８）において、各Ｒ^６１は、相互に独立に、水素原子、直鎖状、分岐状若しくは環状の置換されていてもよいアルキル基、置換されていてもよいアリール基、又は置換されていてもよいアラルキル基を示す。〕

[In the general formula (8), each R ⁶¹ is independently of each other a hydrogen atom, a linear, branched or cyclic alkyl group which may be substituted, an aryl group which may be substituted, or a substituent. The aralkyl group which may be made is shown. ]

^Examples of the alkyl group in R ⁶¹ of the general formula (8) include a linear or branched alkyl group having 1 to 30 carbon atoms and a cyclic alkyl group having 3 to 30 carbon atoms. Specifically, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, cyclopropyl group, cyclopentyl Group, cyclohexyl group, adamantyl group, norbornyl group and the like.

Examples of the aryl group for R ⁶¹ in the general formula (8) include aryl groups having 6 to 14 carbon atoms. Specifically, a phenyl group, a tolyl group, a naphthyl group etc. are mentioned, for example.

Examples of the aralkyl group in R ⁶¹ of the general formula (8) include aralkyl groups having 6 to 12 carbon atoms. Specific examples include a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and the like.

  Moreover, the above-mentioned alkyl group, aryl group, and aralkyl group may be substituted. Specific examples of the substituent include, for example, methyl group, ethyl group, provir group, n-butyl group, t-butyl group, hydroxyl group, carboxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), alkoxyl. Groups (methoxy group, ethoxy group, propoxy group, butoxy group, etc.) and the like.

  Examples of the nitrogen-containing compound (i) include mono (cyclo) alkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, cyclohexylamine; di-n- Butylamine, di-n-pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine, cyclohexylmethylamine, dicyclohexylamine, etc. Di (cyclo) alkylamines;

  Triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri -Tri (cyclo) alkylamines such as n-decylamine, cyclohexyldimethylamine, methyldicyclohexylamine, and tricyclohexylamine; substituted alkylamines such as triethanolamine; aniline, N-methylaniline, N, N-dimethylaniline, 2 -Methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, naphthylamine, 2,4,6-tri-tert-butyl-N-methylaniline, N-phenyldiethanolamine, 2 , - aromatic amines such as diisopropyl aniline.

  Examples of the nitrogen-containing compound (ii) include ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, and 4,4′-diaminodiphenylether. 4,4′-diaminobenzophenone, 4,4′-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, , 4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, bis (2-dimethylaminoethyl) ) Ether, bis (2-diethylaminoethyl) ether, 1- (2-hydroxyethyl) -2-y Dazorijinon, 2 quinoxalinium linoleic, N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine, N, N, N', N '', N '' - pentamethyldiethylenetriamine, and the like.

  Examples of the nitrogen-containing compound (iii) include polyethyleneimine, polyallylamine, 2-dimethylaminoethylacrylamide polymer, and the like.

  Examples of the amide group-containing compound include Nt-butoxycarbonyldi-n-octylamine, Nt-butoxycarbonyldi-n-nonylamine, Nt-butoxycarbonyldi-n-decylamine, Nt- Butoxycarbonyldicyclohexylamine, Nt-butoxycarbonyl-1-adamantylamine, Nt-butoxycarbonyl-2-adamantylamine, Nt-butoxycarbonyl-N-methyl-1-adamantylamine, (S)-( -)-1- (t-butoxycarbonyl) -2-pyrrolidinemethanol, (R)-(+)-1- (t-butoxycarbonyl) -2-pyrrolidinemethanol, Nt-butoxycarbonyl-4-hydroxypiperidine Nt-butoxycarbonylpyrrolidine, Nt-butoxycarbonyl Perazine, N, N-di-t-butoxycarbonyl-1-adamantylamine, N, N-di-t-butoxycarbonyl-N-methyl-1-adamantylamine, Nt-butoxycarbonyl-4,4′- Diaminodiphenylmethane, N, N′-di-t-butoxycarbonylhexamethylenediamine, N, N, N ′, N′-tetra-t-butoxycarbonylhexamethylenediamine, N, N′-di-t-butoxycarbonyl- 1,7-diaminoheptane, N, N′-di-t-butoxycarbonyl-1,8-diaminooctane, N, N′-di-t-butoxycarbonyl-1,9-diaminononane, N, N′-di -T-butoxycarbonyl-1,10-diaminodecane, N, N'-di-t-butoxycarbonyl-1,12-diaminododecane, N, '-Di-t-butoxycarbonyl-4,4'-diaminodiphenylmethane, Nt-butoxycarbonylbenzimidazole, Nt-butoxycarbonyl-2-methylbenzimidazole, Nt-butoxycarbonyl-2-phenylbenz In addition to Nt-butoxycarbonyl group-containing amino compounds such as imidazole, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone N-methylpyrrolidone, N-acetyl-1-adamantylamine, tris (2-hydroxyethyl) isocyanurate, and the like.

  Examples of urea compounds include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n-butylthiourea. Etc.

  Examples of the nitrogen-containing heterocyclic compound include imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2- Imidazoles such as methyl-1H-imidazole; pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine , Nicotine, nicotinic acid, nicotinic acid amide, quinoline, 4-hydroxyquinoline, 8-oxyquinoline, acridine, pyridines such as 2,2 ′: 6 ′, 2 ″ -terpyridine; piperazine, 1- (2-hydroxy In addition to piperazines such as ethyl) piperazine, Gin, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, piperidine ethanol, 3-piperidino-1,2-propanediol, morpholine, 4-methylmorpholine, 1- (4-morpholinyl) ethanol, 4-acetylmorpholine, 3 -(N-morpholino) -1,2-propanediol, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2.2] octane and the like.

  When the radiation sensitive resin composition of this invention contains an acid diffusion control agent, this acid diffusion control agent may contain only 1 type and may contain 2 or more types.

  The content of the acid diffusion controller is preferably 30 parts by mass or less, more preferably 0.1 to 20 parts by mass, and still more preferably 0.1 when the polymer (A) is 100 parts by mass. -10 parts by mass. When this content exceeds 30 parts by mass, the sensitivity is undesirably slowed.

[1-6] Other components The radiation-sensitive resin composition of the present invention may further include various additives such as a surfactant, a sensitizer, and an aliphatic additive, as necessary, as other components. Can be blended.
The surfactant is a component having an action of improving coating properties, striations, developability and the like.
Examples of such surfactants include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, and polyethylene glycol dilaurate. In addition to nonionic surfactants such as polyethylene glycol distearate, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.), Ftop EF301, EF303, EF352 (manufactured by Tochem Products), MegaFuck F171, F173 (manufactured by Dainippon Ink and Chemicals), Florard FC430, FC431 (Sumitomo 3M) Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (made by Asahi Glass Co., Ltd.), etc. Can do. These surfactants may be used individually by 1 type, and may be used in combination of 2 or more type.
Moreover, it is preferable that the compounding quantity of surfactant is 2 mass parts or less with respect to 100 mass parts of polymers (A), More preferably, it is 0.001-2 mass parts.

The sensitizer absorbs radiation energy and transmits the energy to the compound (B) and the acid generator (D), thereby increasing the amount of acid produced. It has the effect of improving the apparent sensitivity of the resin composition.
Examples of such sensitizers include carbazoles, acetophenones, benzophenones, naphthalenes, phenols, biacetyl, eosin, rose bengal, pyrenes, anthracenes, phenothiazines, and the like. In addition, these sensitizers may be used individually by 1 type, and may be used in combination of 2 or more type.
Further, the blending amount of the sensitizer is preferably 10 parts by mass or less, more preferably 0.1 to 10 parts by mass, when the polymer (A) is 100 parts by mass.

  Further, by blending a dye or a pigment, the latent image in the exposed area can be visualized, and the influence of halation during exposure can be reduced. Moreover, the adhesiveness of a resist film and a board | substrate can be improved by mix | blending an adhesion aid.

The alicyclic additive is a component having a function of further improving dry etching resistance, pattern shape, adhesion to a substrate, and the like.
Examples of such alicyclic additives include 1-adamantanecarboxylic acid, 2-adamantanone, 1-adamantanecarboxylic acid t-butyl, 1-adamantanecarboxylic acid t-butoxycarbonylmethyl, 1-adamantanecarboxylic acid α. -Butyrolactone ester, 1,3-adamantane dicarboxylic acid di-t-butyl, 1-adamantane acetate t-butyl, 1-adamantane acetate t-butoxycarbonylmethyl, 1,3-adamantane diacetate di-t-butyl, 2, Adamantane derivatives such as 5-dimethyl-2,5-di (adamantylcarbonyloxy) hexane; t-butyl deoxycholic acid, t-butoxycarbonylmethyl deoxycholic acid, 2-ethoxyethyl deoxycholic acid, 2-deoxycholic acid 2- Cyclohexyloxyethyl, deoxy Deoxycholic acid esters such as 3-oxocyclohexyl cholic acid, tetrahydropyranyl deoxycholic acid, mevalonolactone ester of deoxycholic acid; t-butyl lithocholic acid, t-butoxycarbonylmethyl lithocholic acid, 2-ethoxyethyl lithocholic acid, Lithocholic acid esters such as lithocholic acid 2-cyclohexyloxyethyl, lithocholic acid 3-oxocyclohexyl, lithocholic acid tetrahydropyranyl, lithocholic acid mevalonolactone ester; dimethyl adipate, diethyl adipate, dipropyl adipate, din adipate - butyl, alkyl carboxylic acid esters such as adipate t- butyl or 3- [2-hydroxy-2,2-bis (trifluoromethyl) ethyl] tetracyclo [4.4.0.1 ^{2, 5} 1 ^7,10 ] dodecane and the like. These alicyclic additives may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, when the amount of the alicyclic additive is 100 parts by mass of the polymer (A), it is preferably 20 parts by mass or less, more preferably 0.5 to 20 parts by mass. When the blending amount of the alicyclic additive exceeds 20 parts by mass, the heat resistance of the formed resist film may be lowered.

  Further, additives other than the above include alkali-insoluble or hardly soluble polymers, low-molecular alkali-solubility control agents having acid-dissociable protecting groups, antihalation agents, storage stabilizers, antifoaming agents, etc. Can be mentioned.

[2] Method for Forming Resist Pattern The radiation-sensitive resin composition of the present invention is useful as a material capable of forming a negative resist film.
In the negative resist film, the polymer (A) is crosslinked by the action of the acid generated from the compound (B) and the acid generator (D) by exposure, and the polymer becomes alkali-insoluble. That is, an alkali-insoluble portion is generated in the resist film. Therefore, the unexposed portion remains alkali-soluble, and a negative resist pattern having a desired shape can be formed by dissolving and removing the unexposed portion with an alkali developer. This will be specifically described below.

  The resist pattern is formed by a resist pattern forming method comprising: (1) a step of forming a resist film using the radiation-sensitive resin composition of the present invention; and (2) a step of exposing the obtained resist film. can do.

  In the step of forming a resist film, first, a resist film is formed with the radiation sensitive resin composition of the present invention. As the radiation-sensitive resin composition, for example, as described above, after adjusting the total solid content concentration, it can be filtered with a filter having a pore diameter of about 0.2 μm. By applying this radiation-sensitive resin composition on a substrate such as a silicon wafer or a wafer coated with aluminum by an appropriate application means such as spin coating, cast coating, or roll coating, a resist film is formed. Form. Thereafter, in some cases, heat treatment (hereinafter referred to as “PB”) may be performed at a temperature of about 70 to 160 ° C. in advance.

Next, in the step of exposing the obtained resist film, the resist film is exposed so that a predetermined resist pattern is formed. Examples of radiation that can be used for this exposure include (extreme) far ultraviolet rays such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), EUV (extreme ultraviolet light, wavelength 13.5 nm, etc.), and synchro Examples include X-rays such as tron radiation, and charged particle beams such as electron beams. Among these, it is preferable to use KrF excimer laser, ArF excimer laser, electron beam (EB) or extreme ultraviolet (EUV).
Moreover, exposure conditions, such as exposure amount, can be suitably selected according to the composition of the radiation-sensitive resin composition, the type of additive, and the like. This exposure can also be immersion exposure.

  In addition, it is preferable to perform heat processing (henceforth "PEB") after exposure. By this PEB, it is possible to smoothly proceed with elimination of the acid dissociable group of the polymer. The heating condition of PEB can be appropriately selected depending on the composition of the radiation sensitive resin composition, but is preferably 30 to 200 ° C, more preferably 50 to 170 ° C.

  In the present invention, in order to maximize the potential of the radiation-sensitive resin composition, for example, as disclosed in Japanese Patent Publication No. 6-12252 (Japanese Patent Laid-Open No. 59-93448), etc. An organic or inorganic antireflection film can also be formed on the substrate. Further, in order to prevent the influence of basic impurities contained in the environmental atmosphere, a protective film can be provided on the resist film as disclosed in, for example, JP-A-5-188598. These techniques can be used in combination.

  Next, the exposed resist film is developed to form a predetermined resist pattern. Examples of the developer used for development include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, and di-n-propylamine. , Triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4.3.0] An alkaline aqueous solution in which at least one of alkaline compounds such as 5-nonene is dissolved is preferable.

The concentration of the alkaline aqueous solution is preferably 10% by mass or less. When the concentration of the alkaline aqueous solution exceeds 10% by mass, the exposed area may be dissolved in the developer.
Moreover, it is preferable that a developing solution is pH 8-14, More preferably, it is pH 9-14.

Moreover, an organic solvent can also be added to the developing solution which consists of alkaline aqueous solution, for example. Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone, methyl i-butyl ketone, cyclopentanone, cyclohexanone, 3-methylcyclopentanone, and 2,6-dimethylcyclohexanone; methyl alcohol, ethyl alcohol, and n-propyl. Alcohols such as alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, 1,4-hexanedimethylol; ethers such as tetrahydrofuran and dioxane Esters such as ethyl acetate, n-butyl acetate and i-amyl acetate; aromatic hydrocarbons such as toluene and xylene; phenol, acetonylacetone and dimethylformamide.
These organic solvents may be used individually by 1 type, and may be used in combination of 2 or more type.

The blending amount of the organic solvent is preferably 100 parts by volume or less with respect to 100 parts by volume of the alkaline aqueous solution. When the blending amount of the organic solvent exceeds 100 parts by volume, the developability is lowered, and there is a possibility that the undeveloped portion remains undeveloped. In addition, an appropriate amount of a surfactant or the like can be added to the developer composed of an alkaline aqueous solution.
In addition, after developing with the developing solution which consists of alkaline aqueous solution, it can also wash with water and can be dried.

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Here, “part” and “%” are based on mass unless otherwise specified.

[1] Synthesis of polymer <Synthesis Example 1>
After dissolving 13.0 g of the following compound (M-1), 2.0 g of the following compound (M-2), and 1.2 g of azobisisobutyronitrile (hereinafter referred to as “AIBN”) in 60 g of methyl ethyl ketone, nitrogen is added. Under the atmosphere, the reaction temperature was maintained at 70 ° C., and polymerization was performed for 6 hours. After the polymerization, the reaction solution was dropped into 500 g of n-hexane to solidify the produced copolymer, and the produced white powder was filtered and dried at 50 ° C. under reduced pressure overnight.
As for the obtained copolymer, Mw is 8000, Mw / Mn is 2.3, and as a result of ¹³ C-NMR analysis, the content of each repeating unit derived from the compounds (M-1) and (M-2) ( The molar ratio was 75:25. Hereinafter, this copolymer is referred to as “polymer (A-1)”.

<Synthesis Example 2>
After 18.9 g of the compound (M-1), 11.1 g of p-acetoxystyrene and 1.8 g of AIBN were dissolved in 45 g of methyl ethyl ketone, polymerization was performed for 6 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. . After the polymerization, the reaction solution was dropped into 500 g of n-hexane, and the resulting copolymer was coagulated and purified. Next, after adding 20 g of propylene glycol monomethyl ether to the copolymer again, 20 g of methanol, 7.6 g of triethylamine, and 1.5 g of water were further added, and the mixture was refluxed at the boiling point for 8 hours. Was done. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the resulting copolymer was dissolved in 20 g of acetone, then dropped into 500 g of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
As for the obtained copolymer, Mw is 10000, Mw / Mn is 2.1, and as a result of ¹³ C-NMR analysis, the content of each repeating unit derived from the compound (M-1) and p-hydroxystyrene (mol) The ratio) was a copolymer of 40:60. Hereinafter, this copolymer is referred to as “polymer (A-2)”.

<Synthesis Example 3>
After dissolving 13.3 g of the following compound (M-3), 16.7 g of the following compound (M-4), and 2.0 g of AIBN in 45 g of methyl ethyl ketone, the reaction temperature is maintained at 60 ° C. in a nitrogen atmosphere. Polymerized for hours. After the polymerization, the reaction solution was dropped into 500 g of n-hexane to solidify the produced copolymer, and the produced white powder was filtered and dried at 50 ° C. under reduced pressure overnight.
As for the obtained copolymer, Mw is 10,000, Mw / Mn is 2.5, and as a result of ¹³ C-NMR analysis, the content ratio of each repeating unit derived from the compounds (M-3) and (M-4) ( The molar ratio was a copolymer of 45:55. Hereinafter, this copolymer is referred to as “polymer (A-3)”.

In addition, each following measurement and evaluation in each synthesis example were performed in the following way.
(1) Mw and Mn
Using a GPC column (2 G2000HXL, 1 G3000HXL, 1 G4000HXL) manufactured by Tosoh Corporation, monodisperse polystyrene is the standard under the analysis conditions of flow rate: 1.0 ml / min, elution solvent: tetrahydrofuran, column temperature: 40 ° C. Measured by gel permeation chromatography (GPC). Further, the degree of dispersion Mw / Mn was calculated from the measurement results.
⁽²⁾ 13 C-NMR analysis of ¹³ C-NMR analysis the polymer, using a Nippon Denshi Co. "JNM-EX270", was measured.

[2] Preparation of radiation-sensitive resin composition <Examples 1 to 5>
Polymer (A), compound (B), solvent (C), acid generator (D), and acid diffusion controller (E) were mixed in the amounts shown in Table 1 and the resulting mixture was used. Each composition solution (radiation sensitive resin composition) of Examples 1 to 5 was prepared by filtering with a membrane filter having a pore size of 200 nm.

Details of the polymer (A), the compound (B), the solvent (C), the acid generator (D), and the acid diffusion controller (E) are shown below.
<Polymer (A)>
(A-1): Polymer (A-1) obtained in Synthesis Example 1 above
(A-2): Polymer (A-2) obtained in Synthesis Example 2 above
(A-3): Polymer (A-3) obtained in Synthesis Example 3 above

<Compound (B)>
(B-1): The following compound (B-1) (carboxylic acid generator)

<Solvent (C)>
(C-1): Ethyl lactate (C-2): Propylene glycol monomethyl ether acetate <Acid generator (D)>
(D-1): Triphenylsulfonium trifluoromethanesulfonate <Acid diffusion controller (E)>
(E-1): Tri-n-octylamine

[3] Evaluation of Radiation Sensitive Resin Composition Each composition solution (each radiation sensitive resin composition of Examples 1 to 5) is spin-coated on a silicon wafer in a clean track ACT-8 manufactured by Tokyo Electron. After that, PB (heat treatment) was performed under the conditions shown in Table 2 to form a resist (radiation sensitive resin composition) film having a film thickness of 60 nm. Thereafter, the resist film was irradiated with an electron beam using a simple electron beam drawing apparatus (manufactured by Hitachi, Ltd., model “HL800D”, output: 50 KeV, current density: 5.0 amperes / cm ² ). After the electron beam irradiation, PEB was performed under the conditions shown in Table 2. Thereafter, a 2.38% tetramethylammonium hydroxide aqueous solution was used and developed by the paddle method at 23 ° C. for 1 minute, and then washed with pure water and dried to form a resist pattern. The resist thus formed was evaluated in the following manner. The evaluation results are shown in Table 2.

(1) Sensitivity (L / S)
A pattern [a so-called line-and-space pattern (1L1S)] composed of a line portion having a line width of 150 nm and a space portion (that is, a groove) having an interval of 150 nm formed by adjacent line portions is 1: 1. The exposure amount formed in the line width was set as the optimum exposure amount, and the sensitivity was evaluated based on the optimum exposure amount.
FIG. 1 is a plan view schematically showing the shape of a line and space pattern. FIG. 2 is a cross-sectional view schematically showing the shape of the line and space pattern. However, the unevenness shown in FIGS. 1 and 2 is exaggerated from the actual.

(2) Nano-edge roughness A line-and-space pattern (1L1S) with a design line width of 150 nm is scanned with a scanning electron microscope for semiconductors (high resolution FEB measuring device, trade name “S-9220”, manufactured by Hitachi, Ltd.) ). With respect to the observed shape, as shown in FIG. 1 and FIG. 2, the line width and the design line at the most conspicuous portion of the unevenness generated along the lateral surface 2a of the line part 2 of the resist film formed on the silicon wafer 1 are shown. The difference “ΔCD” from the width of 150 nm was measured by CD-SEM (manufactured by Hitachi High-Technologies Corporation, “S-9220”) to evaluate nanoedge roughness.

(3) Resolution (L / S)
For the line-and-space pattern (1L1S), the minimum line width (nm) of the line pattern resolved with the optimum exposure dose was taken as the resolution.

  According to Table 2, the radiation-sensitive resin compositions of Examples 1 to 5 are sensitive to electron beams or extreme ultraviolet rays, have low roughness and excellent sensitivity and resolution, and have a fine pattern with high accuracy. In addition, it was confirmed that a chemically amplified negative resist film that can be formed stably and stably can be formed.

  The radiation-sensitive resin composition of the present invention is not only excellent in line and space pattern resolution during pattern formation, but also excellent in nano edge roughness, so it is useful for fine pattern formation by EB, EUV and X-rays. is there. Therefore, the radiation-sensitive resin composition of the present invention is extremely useful as a material capable of forming a chemically amplified resist for manufacturing semiconductor devices, which is expected to be further miniaturized in the future.

  DESCRIPTION OF SYMBOLS 1; Base material, 2; Resist pattern, 2a;

Claims (3)

(A) a polymer containing in a side chain at least one of an oxetanyl group and an epoxy group, and at least one of a carboxyl group and a phenolic hydroxyl group;
(B) A radiation-sensitive resin composition comprising: a compound represented by the following general formula (b1) or (b2):

[In General Formulas (b1) and (b2), R ^{31 to} R ³⁵ are each independently a hydrogen atom, a fluorine atom, a trifluoromethyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, A cycloalkyl group having 5 to 25 carbon atoms, -S-R ³⁶ group, -O-SO ₂ -R ³⁷ group, or -SO ₂ -R ³⁸ group (provided that R ^{36 to} R ³⁸ are each independently A linear or branched alkyl group having 1 to 12 carbon atoms substituted or unsubstituted with a fluorine atom, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted with a fluorine atom, or substituted or non-substituted with a fluorine atom. A substituted aryl group having 6 to 22 carbon atoms is shown.). X ₁ ^- and _{X 2} ^- are each ^{independently, OH -, R 39 O -} , ^or, R 40 COO ^- showing the ^{(where, R 39} and ^{R 40} each independently represent a substituted or unsubstituted with fluorine atom A linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 5 to 25 carbon atoms substituted or unsubstituted by a fluorine atom, or a fluorine atom, a trifluoromethyl group, and a hydroxyl group. And a substituted or unsubstituted aryl group having 6 to 22 carbon atoms. ] The polymer is at least one of the repeating units represented by the following general formulas (1-a) and (1-b) and the repeating units represented by the following general formulas (2) to (7) The radiation sensitive resin composition of Claim 1 containing at least 1 sort (s) of these.

[In General Formula (1-a), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ³ , R ⁴ , R ⁵ and R ⁶ each independently represent a hydrogen atom, a fluorine atom, an alkyl group having 1 to 4 carbon atoms, a phenyl group, or a perfluoroalkyl group having 1 to 4 carbon atoms. n is an integer of 1-6. ]

[In General Formula (1-b), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is an integer of 1-6. ]

[In General Formula (2), R ⁷ represents a hydrogen atom or a methyl group. R ⁸ and R ⁹ each independently represent a methylene group, a linear or branched alkylene group having 2 to 6 carbon atoms, or an alicyclic alkylene group having 4 to 12 carbon atoms. ]

[In General Formula (3), R ¹⁰ represents a hydrogen atom or a methyl group. R ¹¹ represents a methylene group, a linear or branched alkylene group having 2 to 6 carbon atoms, or an alicyclic alkylene group having 4 to 12 carbon atoms. ]

In [Formula ^{(4), R 12} represents a hydrogen atom or a methyl group. ]

[In General Formula (5), R ¹³ represents a hydrogen atom or a methyl group. R ¹⁴ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxyl group having 1 to 12 carbon atoms. i and j each independently represent an integer of 0 to 3 (provided that i + j ≦ 5 is satisfied). ]

In [Formula ^{(6), R 15} represents a hydrogen atom or a methyl group. R ¹⁶ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxyl group having 1 to 12 carbon atoms. k and l each independently represent an integer of 0 to 3 (provided that k + l ≦ 5 is satisfied). ]

[In General Formula (7), R ¹⁷ represents a hydrogen atom or a methyl group. R ¹⁸ represents a linear or branched alkyl group having 1 to 12 carbon atoms or a linear or branched alkoxyl group having 1 to 12 carbon atoms. m and n each independently represent an integer of 0 to 3 (provided that m + n ≦ 5 is satisfied). ] (1) forming a resist film using the radiation-sensitive resin composition according to claim 1 or 2,
(2) A pattern forming method comprising: exposing the obtained resist film using a KrF excimer laser, an ArF excimer laser, an electron beam (EB), or extreme ultraviolet (EUV).

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