JP2010160288A - Acid transfer resin film-forming composition, acid transfer resin film, and pattern forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acid transfer resin film-forming composition which obtains an acid transfer resin film superior in the selectivity of acid diffusion and in removability, and to provide an acid transfer resin film formed that uses the composition, and a pattern forming method which enables pattern formation by an existing photolithography process that uses the acid transfer resin film. <P>SOLUTION: The composition comprises an iminosulfonate type radiation-sensitive acid generator and a polymer having a constitutional unit represented by formula (1). The acid transfer resin film is formed by using the composition. The pattern forming method includes a second resin film forming step of forming a second resin film as the acid transfer resin film on a first resin film containing a resin having an acid-dissociable group and not containing a radiation-sensitive acid generator. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an acid transfer resin film forming composition, an acid transfer resin film, and a pattern forming method. More specifically, the present invention relates to an acid transfer resin film forming composition that can be suitably used in a technique for forming a pattern on a film that does not contain an acid generator, an acid transfer resin film using the composition, and a pattern forming method.

In the microfabrication field represented by the manufacture of integrated circuit elements, conventionally, a pattern forming method using a radiation sensitive resin composition containing a resin having an acid dissociable functional group and an acid generator is known. In this method, an acid is generated from the acid generator by exposure, and a property that a predetermined functional group is dissociated from the resin having the acid-dissociable functional group by the acid and becomes alkali-soluble is utilized.
On the other hand, as disclosed in the following Patent Documents 1 to 5, there is known a technique capable of forming a pattern even if an acid generator is not included in the patterned film.

JP 2004-85955 A JP 2001-272402 A WO1990 / 015070 JP 2005-523232 A JP 2006-258806 A

In a technique for forming a pattern on a patterned film that does not contain an acid generator, it is required to selectively diffuse an acid to a necessary portion of the patterned film. Further, when removing the acid transfer film after acid transfer, it is necessary to be able to remove it with a solvent. However, heretofore, there has been no known acid transfer film that can perform diffusion of this acid with sufficient precision and can be easily removed.
The present invention has been made in view of the above circumstances, and provides an acid transfer resin film that has excellent selectivity when diffusing acid, is easy to remove after use, and has excellent sensitivity. It is an object of the present invention to provide a composition for forming an acid transfer resin film, an acid transfer resin film using the composition, and a pattern forming method capable of forming a pattern by an existing photolithography process using the acid transfer resin film.

〔式（１）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２及びＲ^３は、それぞれ独立に、水素原子、炭素数１〜１０の直鎖状又は分枝状の炭化水素基、炭素数３〜１０の環状の炭化水素基を表す。Ｒ^２及びＲ^３は互いに結合して、窒素原子、酸素原子、硫黄原子及びセレン原子の群から選ばれる少なくとも１種のヘテロ原子を有する３〜１０員環の単環式ヘテロ環を形成してもよい。〕
［２］前記式（１）に示す構成単位を有する重合体は、更に、下記式（２）に示す構成単位を有する上記［１］に記載の酸転写樹脂膜形成用組成物。

〔式（２）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２は１価の有機基を表す。〕
［３］上記（Ａ）イミノスルホネート系感放射線性酸発生剤として、下記式（３）に示す化合物を含有する上記［１］又は［２］に記載の酸転写樹脂膜形成用組成物。

〔式（３）中、Ｒ^１は炭素数１〜１４のアルキル基、炭素数６〜２０の芳香族基、炭素数４〜２０の脂環式炭化水素基、又は、これらの基の少なくとも一つの水素原子が、炭素数１〜４のアルキル基、炭素数６〜２０のアリール基若しくは炭化水素基以外の極性基に置換された有機基である。〕
［４］上記［１］乃至［３］のうちのいずれかに記載の酸転写樹脂膜形成用組成物を用いてなることを特徴とする酸転写樹脂膜。
［５］（Ｉ）酸解離性基を有する樹脂を含有し、且つ感放射線性酸発生剤を含有しない第１樹脂膜上に、
上記［１］乃至［３］のうちのいずれかに記載の酸転写樹脂膜形成用組成物を用いてなる酸転写樹脂膜としての第２樹脂膜を形成する第２樹脂膜形成工程と、
（ＩＩ）マスクを介して前記第２樹脂膜に露光し、前記第２樹脂膜に酸を発生させる露光工程と、
（ＩＩＩ）前記第２樹脂膜に発生した前記酸を前記第１樹脂膜に転写する酸転写工程と、
（ＩＶ）前記第２樹脂膜を除去する第２樹脂膜除去工程と、をこの順に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 composition for forming an acid transfer resin film, comprising (A) an iminosulfonate-based radiation-sensitive acid generator, and (B) a polymer having a structural unit represented by the following formula (1): .

Wherein (1), R ¹ represents a hydrogen atom or a methyl group. R ² and R ³ each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group having 3 to 10 carbon atoms. R ² and R ³ are bonded to each other to form a 3- to 10-membered monocyclic heterocycle having at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom. Also good. ]
[2] The acid transfer resin film forming composition according to [1], wherein the polymer having the structural unit represented by the formula (1) further includes a structural unit represented by the following formula (2).

[In formula (2), R ¹ represents a hydrogen atom or a methyl group. R ² represents a monovalent organic group. ]
[3] The composition for forming an acid transfer resin film according to the above [1] or [2], which contains a compound represented by the following formula (3) as the (A) iminosulfonate-based radiation sensitive acid generator.

[In Formula (3), R ¹ is an alkyl group having 1 to 14 carbon atoms, an aromatic group having 6 to 20 carbon atoms, an alicyclic hydrocarbon group having 4 to 20 carbon atoms, or at least one of these groups. An organic group in which two hydrogen atoms are substituted with a polar group other than an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a hydrocarbon group. ]
[4] An acid transfer resin film comprising the composition for forming an acid transfer resin film according to any one of [1] to [3].
[5] On the first resin film containing (I) a resin having an acid dissociable group and not containing a radiation sensitive acid generator,
A second resin film forming step of forming a second resin film as an acid transfer resin film using the acid transfer resin film forming composition according to any one of [1] to [3];
(II) exposing the second resin film through a mask and generating an acid in the second resin film;
(III) an acid transfer step of transferring the acid generated in the second resin film to the first resin film;
(IV) A pattern forming method comprising: a second resin film removing step of removing the second resin film in this order.

According to the composition for forming an acid transfer resin film of the present invention, even if an acid generator is not contained in the first resin film (that is, the patterned resin film) on which a pattern is to be formed, the existing photolithographic process is performed. Can be used to form a pattern. And since it contains both the iminosulfonate-based radioactive acid generator and the polymer having the structural unit of the above formula (1), it has excellent sensitivity compared with other acid transfer resin film-forming compositions, and the acid. Excellent selectivity during diffusion and removability after use. As a result, there is no residue of the acid transfer resin film, and a pattern having excellent dimensional stability can be formed. In particular, in the acid diffusion selectivity, it is possible to effectively suppress acid diffusion in the lateral direction within the patterned resin film.
When the polymer further has a structural unit represented by the formula (2), the transfer efficiency of the generated acid can be controlled better.
When the radioactive acid generator contains the compound represented by the formula (3), compared to the case where this compound is not included, it is possible to obtain further excellent sensitivity and removability of the acid transfer resin film, Particularly good patterns can be formed.

  According to the acid transfer resin film of the present invention, even if the acid generator is not contained in the first resin film (that is, the resin film to be patterned), a pattern can be formed using an existing photolithography process. And since it contains both the imino sulfonate type radioactive acid generator and the polymer which has a structural unit of the said Formula (1), it is excellent in a sensitivity compared with other acid transfer resin films, and at the time of diffusing an acid. Excellent selectivity and removability after use. As a result, there is no residue of the acid transfer resin film, and a pattern having excellent dimensional stability can be formed. In particular, in the acid diffusion selectivity, it is possible to effectively suppress acid diffusion in the lateral direction within the patterned resin film.

  According to the pattern forming method of the present invention, even if an acid generator is not contained in the patterned resin film, a pattern can be formed using an existing photolithography process. In particular, in order to use an acid transfer resin film-forming composition containing both an iminosulfonate-based radioactive acid generator and a polymer having the structural unit of the above formula (1), other acid transfer resin film-forming compositions are used. As compared with the case of using, the sensitivity is excellent, and the selectivity at the time of diffusing the acid and the removability after use are excellent. As a result, there is no residue of the acid transfer resin film, and a pattern having excellent dimensional stability can be formed. In particular, in the acid diffusion selectivity, since the acid diffusion in the lateral direction in the patterned resin film can be effectively suppressed, high dimensional stability is obtained in the obtained pattern, and the intended line It is possible to form a good pattern that more faithfully reproduces andspace.

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

〔式（１）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２及びＲ^３は、それぞれ独立に、水素原子、炭素数１〜１０の直鎖状又は分枝状の炭化水素基、炭素数３〜１０の環状の炭化水素基を表す。Ｒ^２及びＲ^３は互いに結合して、窒素原子、酸素原子、硫黄原子及びセレン原子の群から選ばれる少なくとも１種のヘテロ原子を有する３〜１０員環の単環式ヘテロ環を形成してもよい。〕 [1] Composition for forming an acid transfer resin film The composition for forming an acid transfer resin film of the present invention comprises (A) an iminosulfonate-based radiation-sensitive acid generator, and (B) a structural unit represented by the following formula (1). It contains the polymer which has., It is characterized by the above-mentioned.

Wherein (1), R ¹ represents a hydrogen atom or a methyl group. R ² and R ³ each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group having 3 to 10 carbon atoms. R ² and R ³ are bonded to each other to form a 3- to 10-membered monocyclic heterocycle having at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom. Also good. ]

  The present composition for forming an acid transfer resin film is a composition capable of forming an acid transfer resin film (second resin film) described later. Furthermore, it can be used in a pattern forming method described later. That is, the acid transfer resin film (second resin film) formed from the present composition for forming an acid transfer resin film is formed by subjecting the acid generated from the iminosulfonate-based radiation-sensitive acid generator (A) by exposure to a pattern to be patterned. Can be transferred to the fluorinated resin film (first resin film). Usually, the patterned resin film contains an acid-dissociable group-containing resin, and the acid-dissociable group is dissociated by the acid transferred from the acid transfer resin film (the protecting group is eliminated), and the patterned resin A pattern composed of alkali-soluble sites and alkali-insoluble sites can be formed on the film.

〔式（４）中、Ｒ^１は１価の有機基であり、Ｒ^２は２価の有機基である。このＲ^１及びＲ^２は、各々、炭素原子以外の原子を有することができる。炭素原子以外の原子としては、水素原子、酸素原子、窒素原子、硫黄原子、ハロゲン原子（フッ素原子、塩素原子等）、セレン原子などが挙げられる。〕 <1-1> Iminosulfonate-based radioactive acid generator (A)
The “(A) iminosulfonate-based radioactive acid generator” (hereinafter also simply referred to as “acid generator (A)”) has a structure represented by the following formula (4), and an acid is obtained by exposure. It is a compound having the radiation sensitive performance.

[In Formula (4), R ¹ is a monovalent organic group, and R ² is a divalent organic group. Each of R ¹ and R ² can have an atom other than a carbon atom. Examples of atoms other than carbon atoms include hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), and selenium atoms. ]

Further, the structure of R ^{2 in} the iminosulfonate-based radiation sensitive acid generator (A) is not particularly limited, but is a group having a thiophene ring structure directly bonded to the nitrogen atom in the formula (4). Is preferred. That is, a compound represented by the following formula (5) is preferable.

〔式（５）中、Ｒ^１は１価の有機基であり、Ｒ^２は２価の有機基である。このＲ^１及びＲ^２は、各々、炭素原子以外の原子を有することができる。炭素原子以外の原子としては、水素原子、酸素原子、窒素原子、硫黄原子、ハロゲン原子（フッ素原子、塩素原子等）、セレン原子などが挙げられる。〕
更に、前記式（５）におけるＲ^２の構造は２価の有機基であること以外特に限定されないが、ベンゼン環構造及びニトリル基を有することがより好ましく、酸発生剤（Ａ）として下記式（３）で表される化合物が特に好ましい。

〔式（３）中、Ｒ^１は１価の有機基である。Ｒ^１は炭素原子以外の原子を有することができる。炭素原子以外の原子としては、水素原子、酸素原子、窒素原子、硫黄原子、ハロゲン原子（フッ素原子、塩素原子等）、セレン原子などが挙げられる。〕

[In Formula (5), R ¹ is a monovalent organic group, and R ² is a divalent organic group. Each of R ¹ and R ² can have an atom other than a carbon atom. Examples of atoms other than carbon atoms include hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), and selenium atoms. ]
Further, the structure of R ² in the formula (5) is not particularly limited except that it is a divalent organic group, but it is more preferable to have a benzene ring structure and a nitrile group, and the acid generator (A) has the following formula ( The compound represented by 3) is particularly preferred.

[In Formula (3), R ¹ is a monovalent organic group. R ¹ can have atoms other than carbon atoms. Examples of atoms other than carbon atoms include hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), and selenium atoms. ]

Furthermore, the monovalent organic group as R ¹ in the formula (3) is not particularly limited, but an alkyl group having 1 to 14 carbon atoms, an aromatic group having 6 to 20 carbon atoms, and a fat having 4 to 20 carbon atoms. A cyclic hydrocarbon group, or an organic group in which at least one hydrogen atom of these groups is substituted with a polar group other than an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a hydrocarbon group It is.

Of these, an alkyl group having a carbon number of 1 to 14 as R ¹ in the formula (3) may have a substituent group, but may have no, no substituent is among these It is preferable.
In the case of having a substituent, examples of the substituent include an alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), hydroxy group, carboxyl group, oxo group (= O), cyano group, halogen An atom (a fluorine atom, a chlorine atom, a bromine atom, etc.), an alkyloxycarbonyl group, and the like. In the case of having two or more substituents, each substituent may be the same or different. Good.

前記式（３）におけるＲ^１としてｎ−オクチル基を有する酸発生剤（Ａ）は、下記式（６−２）で示される。

Further, the alkyl group having 1 to 14 carbon atoms as R ¹ in the formula (3) may be a straight chain alkyl group or a branched alkyl group, but is a straight chain alkyl group. Is more preferable. Moreover, the said carbon number should just be 1-14, for example, a methyl group, an ethyl group, a propyl group (n-, i-), n-butyl group, 2-methylpropyl group, n-pentyl group, n- Examples include hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group and the like. Among these, 3-12 are preferable, as for carbon number, 4-10 are more preferable, and n-propyl group and n-octyl group are especially preferable.
The acid generator (A) having an n-propyl group as R ¹ in the formula (3) is represented by the following formula (6-1).

The acid generator (A) having an n-octyl group as R ¹ in the formula (3) is represented by the following formula (6-2).

The aromatic group having 6 to 20 carbon atoms as R ¹ in the formula (3) may have one or two or more substituents. As the substituent, the substituents mentioned in the description of R ^{1 in} the formula (3) can be applied as they are, and in addition, an alkyl group having 1 to 5 carbon atoms can be mentioned. That is, for example, the aromatic group having 6 to 20 carbon atoms as R ¹ in the formula (3) includes a tolyl group (p-, m-, o-), a xylyl group (-2, 4, -3, 5), mesityl group (-2, 4, 6 etc.), benzyl group, cumenyl group (p-, m-, o-), methoxyphenyl group (p-, m-, o-) and the like. Among these, p-tolyl group, 2,4-xylyl group and benzyl are preferable, and p-tolyl group is particularly preferable.
The acid generator (A) having a p-tolyl group as R ¹ in the formula (3) is represented by the following formula (6-3).

The alicyclic group having 4 to 20 carbon atoms as R ¹ in the above formula (3) may or may not contain an unsaturated bond. Furthermore, it may or may not have a substituent. Examples of the substituent in the case of having a substituent include a substituent regarding the alkyl group having 1 to 14 carbon atoms, a methyl group, and an ethyl group.
Furthermore, the alicyclic part of the alicyclic group may be monocyclic or polycyclic, and may be condensed or non-condensed in the case of polycyclic. Good. Moreover, this alicyclic part may be a bridge type or a non-bridge type.
As this alicyclic group, an alicyclic group having a norbornane skeleton, an alicyclic group having a norbornene skeleton, an alicyclic group having a tricyclodecane skeleton, an alicyclic group having a tetracyclododecane skeleton, an adamantane skeleton And an alicyclic group having a cycloalkyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, a cyclododecanyl group, and the like.
Among these, an alicyclic group having a norbornane skeleton is preferable, an alicyclic group having a norbornanone skeleton is more preferable, and an alicyclic group having a camphor skeleton is particularly preferable.

The acid generator (A) described so far is capable of generating an acid by exposure to radiation, but the radiation species exhibiting radiation sensitivity is not particularly limited. , far ultraviolet rays (KrF excimer laser, ArF excimer laser, containing _{F 2} excimer laser), X-rays, electron beams, gamma-rays, molecular beams, can be appropriately used ion beam or the like.

  Moreover, content of an acid generator (A) is although it does not specifically limit, Usually, 0.1-200 mass parts is contained with respect to 100 mass parts of said polymers (B). Furthermore, excellent acid transfer selectivity by combining the acid generator (A) and the polymer (B) (particularly, suppression of acid diffusion in the lateral direction within the patterned resin film) and excellent removal characteristics Therefore, the content is preferably 0.1 to 100 parts by mass, more preferably 0.1 to 80 parts by mass, and particularly preferably 0.1 to 50 parts by mass. .

  In addition to the acid generator (A), the acid transfer resin film forming composition of the present invention may contain other acid generators. Other acid generators include imide sulfonate group-containing compounds, onium salt compounds (including thiophenium salt compounds), halogen-containing compounds, diazoketone compounds, sulfone compounds, sulfonic acid compounds, diazomethane compounds, sulfonimide compounds, and the like. it can. This acid generator (A) may use only 1 type and may use 2 or more types together.

〔式（７）中、Ｒ^１は炭素数１〜１４のアルキル基、炭素数６〜２０のアリール基、又は炭素数４〜２０の脂環式基を表し、Ｒ^２及びＲ^３は、互いに結合して環構造をなすか、又は、各々独立して、炭素数１〜１４のアルキル基、炭素数６〜２０のアリール基、もしくは炭素数４〜２０の脂環式基を表す。〕 The imide sulfonate group-containing compound is a compound represented by the following formula (7).

Wherein (7), ^{R 1} is an alkyl group, an aryl group having 6 to 20 carbon atoms, or an alicyclic group having 4 to 20 carbon atoms having 1 to 14 carbon atoms, ^{R 2} and ^{R 3} are each They are bonded to form a ring structure, or each independently represents an alkyl group having 1 to 14 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an alicyclic group having 4 to 20 carbon atoms. ]

R ² and R ³ in the formula (7) are preferably bonded to each other to form a naphthalene ring structure. Further, each of the alkyl group having 1 to 14 carbon atoms and the alicyclic group having 4 to 20 carbon atoms as R ¹ in the formula (7) includes each of R ¹ in the formula (3). The explanation can be applied as it is. The aryl group having 6 to 20 carbon atoms as R ¹ in the formula (7) includes a tolyl group (p-, m-, o-), a xylyl group (-2, 4, -3, 5, etc.). , A mesityl group (-2, 4, 6 etc.), a benzyl group, a cumenyl group (p-, m-, o-) and the like. Among these, a methyl group is preferable for an alkyl group having 1 to 14 carbon atoms as R ¹ , and a tolyl group (particularly a p-tolyl group) is preferable for an aryl group having 6 to 20 carbon atoms as R ¹ , The alicyclic group having 4 to 20 carbon atoms as R ¹ is preferably an alicyclic group having a camphor skeleton.

  Examples of the onium salt compounds include 4,7-di-n-butoxynaphthyltetrahydrothiophenium salt compounds, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium salt compounds, 1- (6- thiophenium salt compounds such as n-butoxynaphthalen-2-yl) tetrahydrothiophenium salt compound and 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium salt compound; bis (4-t-butylphenyl) ) Iodonium salt compounds such as iodonium salt compounds and diphenyliodonium salt compounds; triphenylsulfonium salt compounds, 4-t-butylphenyldiphenylsulfonium salt compounds, 4-cyclohexylphenyldiphenylsulfonium salt compounds, 4-methanesulfonylphenyldiphenyls Sulfonium salt compounds such as Honiumu salt compounds; phosphonium salt compound; diazonium salt compound; pyridinium salt compounds; and the like.

Examples of the halogen-containing compound include haloalkyl group-containing hydrocarbon compounds and haloalkyl group-containing heterocyclic compounds. Specific examples include (trichloromethyl) -s-triazine derivatives.
Examples of the diazoketone compound include 1,3-diketo-2-diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds, and the like.
Examples of the sulfonated product include β-ketosulfone, β-sulfonylsulfone, and α-diazo compounds of these compounds.
Examples of the sulfonic acid compounds include alkyl sulfonic acid esters, haloalkyl sulfonic acid esters, aryl sulfonic acid esters, and imino sulfonates.
Examples of the diazomethane compound include bis (trifluoromethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, methylsulfonyl-p-toluenesulfonyldiazomethane, cyclohexylsulfonyl- Examples include 1,1-dimethylethylsulfonyldiazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, and the like.

  Examples of the sulfonimide compound include N- (trifluoromethylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- (trifluoromethylsulfonyloxy). Bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2 , 3-dicarboximide, N- (trifluoromethylsulfonyloxy) -5,6-oxy-bicyclo [2.2.1] heptane-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) Naphthylimide, N- (4-methylphenylsulfonyloxy) s Synimide, N- (4-methylphenylsulfonyloxy) phthalimide, N- (4-methylphenylsulfonyloxy) diphenylmaleimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene -2,3-dicarboximide, N- (4-methylphenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (4- Methylphenylsulfonyloxy) -5,6-oxy-bicyclo [2.2.1] heptane-2,3-dicarboximide, N- (4-methylphenylsulfonyloxy) naphthylimide, N- (2-trifluoro) Methylphenylsulfonyloxy) succinimide, N- (2-trifluoromethylphenylsulfonyloxy) Phthalimide, N- (2-trifluoromethylphenylsulfonyloxy) diphenylmaleimide, N- (2-trifluoromethylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide N- (2-trifluoromethylphenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2-trifluoromethylphenylsulfonyloxy) ) -5,6-oxy-bicyclo [2.2.1] heptane-2,3-dicarboximide, N- (2-trifluoromethylphenylsulfonyloxy) naphthylimide, N- (4-fluorophenylsulfonyloxy) ) Succinimide, N- (4-fluorophenylsulfonyloxy) -7-oxabi Cyclo [2.1.1] hept-5-ene-2,3-dicarboximide, N- (4-fluorophenylsulfonyloxy) -5,6-oxy-bicyclo [2.2.1] heptane-2 , 3-dicarboximide, N- (4-fluorophenylsulfonyloxy) naphthylimide, N- (10-camphor-sulfonyloxy) naphthylimide, and the like.

  When other acid generators other than these acid generators (A) are contained, the content is not particularly limited, but is preferably 200 parts by mass or less with respect to 100 parts by mass of the polymer (B). 0.1-100 mass parts is more preferable, and 0.1-50 mass parts is still more preferable.

〔式（１）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２及びＲ^３は、それぞれ独立に、水素原子、炭素数１〜１０の直鎖状又は分枝状の炭化水素基、炭素数３〜１０の環状の炭化水素基を表す。Ｒ^２及びＲ^３は互いに結合して、窒素原子、酸素原子、硫黄原子及びセレン原子の群から選ばれる少なくとも１種のヘテロ原子を有する３〜１０員環の単環式ヘテロ環を形成してもよい。〕 <1-2> Polymer (B)
The “(B) polymer having a structural unit represented by the following formula (1)” (hereinafter, also simply referred to as “polymer (B)”) contains the acid from the acid generator (A). When this occurs, unnecessary acid diffusion in the acid transfer resin film can be prevented (that is, it functions as an acid diffusion preventing resin). For this reason, unintended acid transfer (acid diffusion) to other layers can be prevented, and the resolution of the resulting pattern can be improved.

Wherein (1), R ¹ represents a hydrogen atom or a methyl group. R ² and R ³ each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group having 3 to 10 carbon atoms. R ² and R ^3, taken together, a nitrogen atom, an oxygen atom, to form a monocyclic heterocyclic ring of 3 to 10-membered ring having at least one hetero atom selected from the group consisting of sulfur atom and selenium atom Also good. ]

〔式（８）式中、Ｒ^１は水素原子又はメチル基であり、Ｒ^２及びＲ^３は、それぞれ独立に、水素原子、炭素数１〜１０の直鎖状又は分枝状の炭化水素基、炭素数３〜１０の環状の炭化水素基を表す。Ｒ^２及びＲ^３は互いに結合して、窒素原子、酸素原子、硫黄原子及びセレン原子の群から選ばれる少なくとも１種のヘテロ原子を有する３〜１０員環の単環式ヘテロ環を形成してもよい。〕 The structural unit represented by the above formula (1) may be contained in any manner in the polymer (B), but is usually a monomer (Bm1) represented by the following formula (8) It can be obtained by polymerizing the polymer (B) using

Wherein (8), R ¹ is hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom, a linear or branched hydrocarbon group having 1 to 10 carbon atoms Represents a cyclic hydrocarbon group having 3 to 10 carbon atoms. R ² and R ³ are bonded to each other to form a 3- to 10-membered monocyclic heterocycle having at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom. Also good. ]

Examples of the linear or branched hydrocarbon group having 1 to 10 carbon atoms that is R ² and / or R ³ in the formula (8) include, for example, methyl group, ethyl group, n-propyl group, i- Examples thereof include aliphatic hydrocarbon groups such as propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group.
That is, as the monomer (Bm1) in which R ² and / or R ³ in Formula (8) is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, N, N-dimethyl ( Examples include meth) acrylamide, N, N-diethyl (meth) acrylamide, and N-isopropyl (meth) acrylamide.

Examples of the cyclic hydrocarbon group having 3 to 10 carbon atoms to be R ² and / or R ³ in the formula (8) include cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooctyl group. Cyclic group; aromatic groups such as phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 4-t-butylphenyl group, 1-naphthyl group, and benzyl group.

Furthermore, 3 to 10 having at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom, formed by bonding R ² and R ³ in the formula (8) to each other. Examples of the monomer (Bm1) forming a membered monocyclic heterocycle include N- (meth) acryloylmorpholine.

  As the monomer (Bm1), among the various monomers, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N-acryloylmorpholine, and N-methacryloylmorpholine are preferable. The polymer (B) obtained using these preferred monomers can more effectively prevent unnecessary diffusion of the acid generated from the acid generator (A) in the acid transfer resin film, It is possible to further improve the resolution of the pattern obtained by preventing unintentional acid transfer (acid diffusion).

  The proportion of the structural unit represented by the formula (1) in the polymer (B) is not particularly limited, but is 1 to 50 mol% when the total structural unit of the polymer (B) is 100 mol%. It is preferable that it is 3-40 mol%, and it is especially preferable that it is 5-30 mol%. When the proportion of the structural unit represented by the formula (1) in the polymer (B) is within the above range, unnecessary diffusion of the acid generated from the acid generator (A) in the acid transfer resin film is more effective. The resolution of the pattern obtained by preventing unintentional acid transfer (acid diffusion) to other layers can be further improved.

〔式（２）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２は１価の有機基を表す。〕 The polymer (B) can contain other structural units in addition to the structural unit represented by the formula (1). The other structural unit is preferably a structural unit represented by the following formula (2).

[In formula (2), R ¹ represents a hydrogen atom or a methyl group. R ² represents a monovalent organic group. ]

  The structural unit represented by the formula (2) may be contained in the polymer (B) in any way, but is usually a monomer (Bm2) represented by the following formula (9) By using this, a polymer (B) containing the structural unit represented by the formula (2) can be obtained.

〔式（９）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２は１価の有機基を表す。〕

[In Formula (9), R ¹ represents a hydrogen atom or a methyl group. R ² represents a monovalent organic group. ]

Examples of the monovalent organic group represented by R ² in the formula (9) 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, a linear or branched alkyl group having 1 to 12 carbon atoms such as a t-butyl group;

  Phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,4-xylyl group, 2,6-xylyl group, 3,5-xylyl group, mesityl group, o-cumenyl group, m-cumenyl Groups, p-cumenyl groups, benzyl groups, phenethyl groups, 1-naphthyl groups, 2-naphthyl groups and other aromatic hydrocarbon groups (especially aromatic hydrocarbon groups having 6 to 20 carbon atoms);

  Hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, 1-hydroxypropyl group, 2-hydroxypropyl group, 3-hydroxypropyl group, 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl Groups, 4-hydroxybutyl groups, 3-hydroxycyclopentyl groups, 4-hydroxycyclohexyl groups and other hydroxyalkyl groups (particularly hydroxyalkyl groups having 1 to 8 carbon atoms);

  Cyano group; cyanomethyl group, 1-cyanoethyl group, 2-cyanoethyl group, 1-cyanopropyl group, 2-cyanopropyl group, 3-cyanopropyl group, 1-cyanobutyl group, 2-cyanobutyl group, 3-cyanobutyl group, 4 A nitrogen atom-containing organic group (particularly a nitrogen atom-containing organic group having 2 to 9 carbon atoms) such as a cyanoalkyl group such as a cyanobutyl group, a 3-cyanocyclopentyl group or a 4-cyanocyclohexyl group;

Examples thereof include alicyclic groups such as cyclic hydrocarbon groups such as cyclopentyl group and cyclohexyl group; bridged cyclic hydrocarbon groups such as bornyl group and isobornyl group.
In addition, although R < ² > in the said Formula (9) may be an acid dissociable group represented by Formula (10) mentioned later, it is preferable that R < ² > is not an acid dissociable group.

The monomer (Bm2) is preferably a (meth) acrylate compound, specifically, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, glycerol mono (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) ) Acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and the like. These (meth) acrylate compounds may be used alone or in combination of two or more.
Of these (meth) acrylate compounds, methyl methacrylate is particularly preferable.

  The proportion of the structural unit represented by the formula (2) in the polymer (B) is not particularly limited, but is 5 to 99 mol% when the total structural unit of the polymer (B) is 100 mol%. It is preferably 10 to 97 mol%, more preferably 15 to 95 mol%. When the proportion of the structural unit represented by the formula (2) in the polymer (B) is within the above range, unnecessary diffusion of the acid generated from the acid generator (A) in the acid transfer resin film can be prevented. Further, it is possible to improve the resolution of a pattern obtained by preventing unintentional acid transfer (acid diffusion) to other layers.

  A polymer (B) can contain other structural units other than the structural unit shown to the said Formula (1), and the structural unit shown to the said Formula (2). The type of other structural unit is not particularly limited as long as it does not impair the object of the present invention. When other structural units are included, the ratio is not particularly limited, but is preferably 30 mol% or less, when the total structural units of the polymer (B) are 100 mol%, preferably 1 to 10 mol% It is more preferable that Within this range, the object of the present invention is not impaired.

  Further, when both the structural unit represented by the formula (1) and the structural unit represented by the formula (2) are included and other structural units are contained, the formula (1) ) And the content of each of the structural units represented by the formula (2) are 100 mol in total of the structural unit represented by the formula (1) and the structural unit represented by the formula (2). %, The structural unit represented by the formula (1) is preferably 1 to 50 mol%, more preferably 3 to 40 mol%, and particularly preferably 5 to 30 mol%. . Within this range, unnecessary diffusion of the acid generated from the acid generator (A) in the acid transfer resin film can be more effectively prevented, and unintentional acid transfer (acid diffusion) to other layers can be prevented. The resolution of the resulting pattern can be further improved.

The molecular weight of the polymer (B) is not particularly limited and may be appropriately selected. The polystyrene-equivalent weight molecular weight (hereinafter referred to as “Mw”) measured by gel permeation chromatography (GPC). Usually, it is 1,000 to 500,000, preferably 2,000 to 400,000, and more preferably 3,000 to 300,000.
Further, the ratio (Mw / Mn) between the Mw of the polymer (B) and the polystyrene-equivalent molecular weight (hereinafter referred to as “Mn”) measured by GPC is not particularly limited and can be appropriately selected. It is 1-10, Preferably it is 1-8, More preferably, it is 1-3.

  The acid transfer resin film to be described later may be formed in any manner from the acid transfer resin film forming composition of the present invention. Usually, a liquid acid transfer resin film forming composition is used as a target surface ( For example, it is formed by applying to the patterned resin film) and drying {and can be heat-treated (baked) if necessary}. For this reason, in addition to the said acid generator (A) and the said polymer (B), this composition for acid transfer resin film formation can contain a solvent (C).

Although the kind of said solvent (C) is not specifically limited, For example, water and / or an organic solvent etc. can be used. These may use only 1 type and may use 2 or more types together.
Examples of the organic solvent include propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol. Diethyl ether, diethylene glycol ethyl methyl ether, dipropyl ether, diisopropyl ether, butyl methyl ether, butyl ethyl ether, butyl propyl ether, dibutyl ether, diisobutyl ether, tert-butyl methyl ether, tert-butyl ethyl ether, tert-butylpropyl ether, di-tert-butyl ether, dipentyl ether, diisoamyl ether, cyclopentyl methyl ether, cyclohexyl methyl ether, cyclopentyl ethyl ether, cyclohexyl ethyl ether, cyclopentyl propyl ether, cyclopentyl-2-propyl ether, cyclohexyl propyl ether, Alkyl ethers such as cyclohexyl-2-propyl ether, cyclopentyl butyl ether, cyclopentyl-tert-butyl ether, cyclohexyl butyl ether, cyclohexyl-tert-butyl ether;

1-propanol, n-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-propanol, neopentyl alcohol, tert-amyl alcohol, isoamyl alcohol, 3-methyl Alkyl alcohols such as 2-butanol, 2-methyl-1-butanol, 2-ethyl-1-butanol, 2-methyl-1-pentanol, 4-methyl-2-pentanol;
Examples include hydrocarbons such as decane, dodecane, undecane, benzene, toluene, and xylene.

In the composition for forming an acid transfer resin film, the solvent (C) is usually contained in an amount of 10 to 10000 parts by mass, preferably 20 to 8000 parts by mass, when the polymer (B) is 100 parts by mass. 30 to 6000 parts by mass is more preferable, and 40 to 4000 parts by mass is still more preferable.
Furthermore, the viscosity of the entire composition for forming an acid transfer resin film is not particularly limited, and may be set to an appropriate viscosity according to a method for applying the composition for forming an acid transfer resin film. For example, the viscosity at a temperature of 25 ° C. It can be set to 1 to 100 mPa · s. This viscosity is preferably 2 to 80 mPa · s, and more preferably 3 to 50 mPa · s.

  In addition, the present composition for forming an acid transfer resin film may contain other components in addition to the solvent (C). Surfactant (D) is mentioned as another component. Examples of the surfactant (D) include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, silicone surfactants, polyalkylene oxide surfactants, and fluorine-containing surfactants. Surfactant etc. are mentioned.

Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate NBX-7, NBX-8, NBX-15 (trade name, manufactured by Neos), SH8400 FLUID (trade name, manufactured by Toray Dow Corning Silicon Co.), KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) ), Polyflow No. 75, no. 95 (trade name, manufactured by Kyoeisha Chemical Co., Ltd.), F Top EF301, EF303, EF352 (trade name, manufactured by Tochem Products Co., Ltd.), Megafax F171, F172, F173, F471, R-07, R-08 (Trade name, manufactured by Dainippon Ink & Chemicals, Inc.), Florard FC430, FC431 (trade name, manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (trade name, manufactured by Asahi Glass Co., Ltd.) and the like can be mentioned. In addition, these may use only 1 type and may use 2 or more types together.
When this surfactant (D) is used, the amount thereof is not particularly limited, but is usually 0.01 to 0.5 parts by mass, preferably 0 with respect to 100 parts by mass of the total amount of the polymer (B). 0.02 to 0.1 part by mass.

  In addition, a sensitizer, a crosslinking agent, an antihalation agent, a storage stabilizer, a colorant, a plasticizer, an antifoaming agent, and the like can be appropriately added to the acid transfer resin film forming composition.

[2] Acid transfer resin film The acid transfer resin film of the present invention is characterized by using the acid transfer resin film forming composition of the present invention.
That is, the acid transfer resin film of the present invention is a film made of a resin containing an acid generator (A) and a polymer (B). With respect to these acid generator (A) and polymer (B), the above descriptions can be applied as they are. In the acid transfer resin film of the present invention, the polymer contained in the acid transfer resin film-forming composition is usually contained without causing a structural change such as crosslinking.
The acid transfer resin film only needs to be formed using the composition for forming an acid transfer resin film, and may be formed by any method. That is, for example, after applying the acid transfer resin film-forming composition containing the solvent (C), part or all of the solvent (C) is removed, and further, heat treatment (baking) is performed as necessary. By applying, an acid transfer resin film can be obtained.

[3] Pattern Forming Method As illustrated in FIG.
(I) On the 1st resin film which contains resin which has an acid dissociable group, and does not contain a radiation sensitive acid generator, For acid transfer resin film formation in any one of Claims 1 thru | or 4 A second resin film forming step of forming a second resin film as an acid transfer resin film using the composition;
(II) exposing the second resin film through a mask and generating an acid in the second resin film;
(III) an acid transfer step of transferring the acid generated in the second resin film to the first resin film;
(IV) A second resin film removing step for removing the second resin film is provided in this order.

[1-1] Second resin film (acid transfer resin film) formation step (I)
The second resin film forming step (I) is a step of forming a second resin film (acid transfer resin film) on the first resin film (patterned resin film).
<1> First resin film (patterned resin film)
The “first resin film” is a resin film containing a resin having an acid dissociable group (hereinafter, also simply referred to as “acid dissociable group-containing resin”) and not containing a radiation sensitive acid generator. In general, the first resin film is alkali-insoluble or alkali-insoluble, and becomes alkali-soluble when the acid-dissociable group is dissociated from the acid-dissociable group-containing resin. The term “alkali-insoluble or alkali-insoluble” as used herein means 50% of the initial film thickness of the film when the film using only the acid-dissociable group-containing resin is developed under alkaline development conditions in the examples described later. This means the remaining properties. On the other hand, “alkali-soluble” means the property of being dissolved in excess of 50% under the above conditions.

  Further, the first resin film includes a resin film before patterning (that is, a resin film to be patterned) and a pattern resin film after patterning (that is, a pattern). That is, the first resin film becomes a “pattern” composed of a portion where the acid is transferred and a portion where the acid is not transferred, through the steps (I) to (VI). Further, by performing the development step (V) as necessary, the portion where the acid has been transferred is removed, so that the portion where the acid is not transferred and the portion where the acid is not transferred (for example, a substrate under the layer) , A portion where the surface of the substrate is exposed) can be formed.

<1-1> Resin Having Acid-Dissociable Group The “acid-dissociable group” is a group that dissociates in the presence of an acid, and is a hydrogen atom in an acidic group such as a phenolic hydroxyl group, a carboxyl group, or a sulfonic acid group. The group which substitutes is meant. As this acid dissociable group, t-butoxycarbonyl group, tetrahydropyranyl group, tetrahydrofuranyl group, (thiotetrahydropyranylsulfanyl) methyl group, (thiotetrahydrofuranylsulfanyl) methyl group, alkoxy-substituted methyl group, alkylsulfanyl Examples thereof include a substituted methyl group and a group represented by the following formula (10) (hereinafter referred to as “acid-dissociable group (10)”).

〔式（１０）において、各Ｒは相互に独立に炭素数１〜１４の直鎖状若しくは分岐状のアルキル基又は炭素数３〜２０の非有橋式若しくは有橋式の１価の脂環式基を示すか、或いは何れか２つのＲが相互に結合して、それぞれが結合している炭素原子と共に、炭素数３〜２０の非有橋式若しくは有橋式の２価の脂環式基を形成し、残りのＲが炭素数１〜１４の直鎖状若しくは分岐状のアルキル基又は炭素数３〜２０の非有橋式若しくは有橋式の１価の脂環式基を示し、これらの各基は置換されていてもよい。〕

[In the formula (10), each R is independently a linear or branched alkyl group having 1 to 14 carbon atoms or a non-bridged or bridged monovalent alicyclic ring having 3 to 20 carbon atoms. A non-bridged or bridged divalent alicyclic group having 3 to 20 carbon atoms together with the carbon atom to which each two Rs are bonded to each other, A remaining R represents a linear or branched alkyl group having 1 to 14 carbon atoms or a non-bridged or bridged monovalent alicyclic group having 3 to 20 carbon atoms, Each of these groups may be substituted. ]

  Examples of the alkoxy-substituted methyl group include methoxymethyl group, ethoxymethyl group, methoxyethoxymethyl group, n-propoxymethyl group, n-butoxymethyl group, n-pentyloxymethyl group, n-hexyloxymethyl group, and benzyl. An oxymethyl group etc. can be mentioned.

  Examples of the alkylsulfanyl-substituted methyl group include a methylsulfanylmethyl group, an ethylsulfanylmethyl group, a methoxyethylsulfanylmethyl group, an n-propylsulfanylmethyl group, an n-butylsulfanylmethyl group, an n-pentylsulfanylmethyl group, Examples thereof include an n-hexylsulfanylmethyl group and a benzylsulfanylmethyl group.

  In the formula (10), examples of the linear or branched alkyl group having 1 to 14 carbon atoms of R include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, 2 -Methylpropyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, Examples thereof include an n-tetradecyl group.

  Examples of the substituent of the alkyl group include a hydroxyl group, a carboxyl group, an oxo group (═O), a cyano group, a halogen atom (for example, a fluorine atom, a chlorine atom, etc.), a straight chain having 1 to 8 carbon atoms, Branched alkoxyl group (for example, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group, etc.), carbon number 2-8 linear or branched alkoxyalkoxyl groups (for example, methoxymethoxy group, ethoxymethoxy group, t-butoxymethoxy group, etc.), C2-C8 linear or branched alkylcarbonyloxy group (For example, methylcarbonyloxy group, ethylcarbonyloxy group, t-butylcarbonyloxy group, etc.), straight chain having 2 to 8 carbon atoms Or branched alkoxycarbonyl group (e.g., methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group) can be exemplified one or more, or one or more such.

Examples of the non-bridged or bridged monovalent alicyclic group having 3 to 20 carbon atoms of R in the formula (10) include, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group cycloheptyl. Group, a cycloalkyl group such as cyclooctyl group; bicyclo [2.2.1] heptyl group, bicyclo [2.2.2] octyl group, tetracyclo [4.2.0.1 ^2,5 . 1 ^7,10 ] dodecyl group, adamantyl group and the like.

  Examples of the substituent of the divalent alicyclic group formed by bonding the monovalent alicyclic group of R in the formula (10) and any two R's to each other include, for example, a hydroxyl group and a carboxyl group , An oxo group (= O), a cyano group, a halogen atom (for example, a fluorine atom, a chlorine atom, etc.), a linear or branched alkyl group having 1 to 14 carbon atoms (for example, a methyl group, an ethyl group, n- Propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, etc.), a linear or branched alkoxyl group having 1 to 8 carbon atoms (for example, A methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, a 2-methylpropoxy group, a 1-methylpropoxy group, a t-butoxy group, etc.), a straight chain having 2 to 8 carbon atoms or Branched alkoxy Kill group (for example, methoxymethyl group, ethoxymethyl group, t-butoxymethyl group, etc.), C2-C8 linear or branched alkoxyalkoxyl group (for example, methoxymethoxy group, ethoxymethoxy group, t- Butoxymethoxy group, etc.), a linear or branched alkylcarbonyloxy group having 2 to 8 carbon atoms (for example, methylcarbonyloxy group, ethylcarbonyloxy group, t-butylcarbonyloxy group, etc.), C2-8 A linear or branched alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group, etc.), a linear or branched cyanoalkyl group having 2 to 14 carbon atoms (for example, cyanomethyl) Group, 2-cyanoethyl group, 3-cyanopropyl group, 4-cyanobutyl group, etc.), charcoal The number 1 to 14 linear or branched fluoroalkyl group (e.g., fluoromethyl group, trifluoromethyl group, pentafluoroethyl group and the like) can be given one or more, or one or more such.

  Specific examples of the acid dissociable group (10) are represented by t-butyl groups and the following formulas (10-1) to (10-20) (where each m is an integer of 0 to 2). Groups and the like.

〔式（１１）において、Ｒ^１は水素原子又はメチル基を示す。Ｘは酸解離性基を示す。〕 Further, the acid dissociable group may be contained in any manner within the acid dissociable group-containing resin. However, the structural unit represented by the following formula (11) (hereinafter simply referred to as “acid dissociable group-containing unit”) (Also referred to as a part).

[In Formula (11), R < ¹ > shows a hydrogen atom or a methyl group. X represents an acid dissociable group. ]

  The acid-dissociable group-containing unit may be contained in any way within the acid-dissociable group-containing resin. For example, using an acid-dissociable group-containing monomer, It can be obtained by polymerizing the resin. That is, examples of the monomer having an acid dissociable group include t-butyl (meth) acrylate, 1,1-dimethyl-propyl (meth) acrylate, 1,1-dimethyl-butyl (meth) acrylate, 2- Cyclohexylpropyl (meth) acrylate, 1,1-dimethyl-phenyl (meth) acrylate, tetrahydropyranyl (meth) acrylate, 2-t-butoxycarbonylmethyl (meth) acrylate, 2-benzyloxycarbonylethyl (meth) acrylate, Examples include 2-methyladamantyl (meth) acrylate, 1,1-dimethyl-3-oxobutyl (meth) acrylate, and 2-benzylpropyl (meth) acrylate.

  The ratio of the acid-dissociable group-containing unit is not particularly limited, but is preferably 5 to 95 mol%, and preferably 10 to 90 mol% when all the structural units of the acid-dissociable group-containing resin are 100 mol%. More preferably, it is more preferably 15 to 80 mol%. When the ratio of the acid dissociable group-containing unit in the acid dissociable group-containing resin is within the above range, a sufficient exposure margin (exposure margin) can be secured.

  In addition, the acid dissociable group-containing resin usually has other structural units. Examples of the other structural unit include structural units having an acidic group such as a phenolic hydroxyl group. When the acid-dissociable group-containing resin contains a structural unit having an acidic group, the solubility of the first resin film in the developer can be adjusted. Examples of the monomer that gives a structural unit having a phenolic hydroxyl group include phenols such as p-isopropenylphenol, m-isopropenylphenol, o-isopropenylphenol, p-hydroxystyrene, m-hydroxystyrene, and o-hydroxystyrene. And a functional hydroxyl group-containing compound. These phenolic hydroxyl group-containing compounds may be used alone or in combination of two or more.

  When the acid-dissociable group-containing resin has a structural unit derived from a phenolic hydroxyl group-containing compound, the ratio is not particularly limited, but when the total structural unit of the acid-dissociable group-containing resin is 100 mol%, 1 It is preferably ˜50 mol%, more preferably 3 to 45 mol%, and particularly preferably 5 to 40 mol%. When the proportion of the structural unit derived from the phenolic hydroxyl group-containing compound in the acid dissociable group-containing resin is within the above range, the solubility (alkali solubility) in the developer when the developing step (V) is performed is adjusted. Can do.

  Moreover, the amount of the acid-dissociable group-containing resin constituting the first resin film is not particularly limited, but when the total amount of the first resin film is 100% by mass, the acid-dissociable group-containing resin is 10 to 99.9. It is preferable that it is mass%, It is more preferable that it is 30-99.9 mass%, It is still more preferable that it is 50-99.9 mass%. When the ratio of the acid-dissociable group-containing resin in the first resin film is within the above range, a dissolution (alkali dissolution) contrast in the developer when performing the development step (V) can be provided (dissolution difference in the developer). Can be turned on)

When the acid-dissociable group-containing resin is produced by or through polymerization of a polymerizable unsaturated monomer, the resin is derived from a polyfunctional monomer having two or more polymerizable unsaturated bonds. A branched structure can be introduced by a structural unit and / or an acetal crosslinking group. By introducing such a branched structure, the heat resistance of the acid-dissociable group-containing resin can be improved.
In this case, the introduction rate of the branched structure in the acid-dissociable group-containing resin can be appropriately selected depending on the branched structure and the type of the resin into which the branched structure is introduced. Preferably there is.

The molecular weight of the acid-dissociable group-containing resin is not particularly limited and may be appropriately selected. The polystyrene-reduced weight molecular weight (hereinafter referred to as “Mw”) measured by gel permeation chromatography (GPC) is usually used. 1,000 to 500,000, preferably 2,000 to 400,000, and more preferably 3,000 to 300,000.
The ratio (Mw / Mn) between the Mw of the acid-dissociable group-containing resin and the polystyrene equivalent number molecular weight (hereinafter referred to as “Mn”) measured by GPC is not particularly limited and can be appropriately selected. 1-10, preferably 1-8, more preferably 1-5.

The method for producing the acid-dissociable group-containing resin is not particularly limited. For example, a method of introducing one or more acid-dissociable groups into acidic groups in an alkali-soluble resin produced in advance; 1 having an acid-dissociable group A method of polymerizing one or more polymerizable unsaturated monomers, optionally together with other polymerizable unsaturated monomers; one or more polycondensable components having acid dissociable groups, optionally It can be produced by a polycondensation method together with a condensable component.
Polymerization of the polymerizable unsaturated monomer and the polymerization of one or more polymerizable unsaturated monomers having an acid dissociable group in the production of the alkali-soluble resin are carried out by using the polymerizable unsaturated monomer used Depending on the type of reaction medium, etc., a polymerization initiator such as a radical polymerization initiator, an anionic polymerization catalyst, a coordination anion polymerization catalyst, a cationic polymerization catalyst, or a polymerization catalyst is appropriately selected, bulk polymerization, solution polymerization, precipitation polymerization, It can implement by appropriate polymerization forms, such as emulsion polymerization, suspension polymerization, and block-suspension polymerization.
The polycondensation of one or more polycondensable components having an acid dissociable group can be preferably carried out in an aqueous medium or a mixed medium of water and a hydrophilic solvent in the presence of an acidic catalyst.

The first resin film may be formed in any way, but is usually formed by applying a liquid first resin film forming composition onto a surface such as a substrate and drying it. In addition to the acid-dissociable group-containing resin, the first resin film-forming composition can make the entire composition liquid by containing a solvent.
As the solvent, the solvent (C) can be applied as it is. Only 1 type may be used for a solvent and it may use 2 or more types together. Further, the solvents contained in the first resin film-forming composition and the acid transfer resin film-forming composition may be the same or different.

When a solvent is contained in the first resin film forming composition, when the acid-dissociable group-containing resin is 100 parts by mass, usually 10 to 10000 parts by mass are contained, and 20 to 8000 parts by mass are preferable. 30-6000 mass parts is more preferable, and 40-4000 mass parts is still more preferable.
Furthermore, the viscosity of the entire first resin film-forming composition is not particularly limited, and may be set to an appropriate viscosity by a method of applying the first resin film-fatty film-forming composition, for example, at a temperature of 25 ° C. The viscosity can be 1 to 100 mPa · s. This viscosity is preferably 2 to 80 mPa · s, and more preferably 3 to 50 mPa · s.

In addition to the solvent, the first resin film-forming composition may contain other components. Examples of other components include surfactants. As the surfactant, the surfactant (D) can be applied as it is. Only one type of surfactant may be used, or two or more types may be used in combination. The surfactant contained in each of the first resin film-forming composition and the acid transfer resin film-forming composition may be the same or different.
When the surfactant is contained in the first resin film forming composition, the amount is not particularly limited, but is usually 0.01 to 1 part by mass with respect to 100 parts by mass of the total amount of the acid dissociable group-containing resin. Preferably, it is 0.02-0.8 mass part.
Furthermore, a crosslinking agent, an antihalation agent, a storage stabilizer, a colorant, a plasticizer, an antifoaming agent, and the like can be appropriately blended with the first resin film forming composition.

The first resin film may be formed on the surface of any member, but is usually formed on the surface of various substrates. Examples of the material of the substrate (at least the material of the surface) include silicon, various metals (such as aluminum), various metal (such as aluminum) sputtered films, alumina, glass epoxy, paper phenol, and glass. Furthermore, the thickness of the substrate is usually 1000 to 10,000 nm.
Furthermore, although the thickness of the formed 1st resin film is not specifically limited, Usually, it is 1-1000 nm, it is preferable to set it as 5-500 nm, and it is still more preferable to set it as 10-100 nm.

Moreover, the application means of the 1st resin film formation composition is although it does not specifically limit, For example, appropriate application means, such as spin coating, cast coating, roll coating, are mentioned.
Furthermore, after apply | coating the composition for 1st resin film formation, you may form a 1st resin film by volatilizing the solvent in a coating film by pre-baking (PB) as needed. The prebaking heating conditions are appropriately selected depending on the composition of the first resin film-forming composition, but the heating temperature is usually about 30 to 150 ° C, preferably 50 to 130 ° C. Furthermore, the heating time is usually 30 to 300 seconds, preferably 60 to 180 seconds.

<2> Second resin film (acid transfer resin film)
The “second resin film (acid transfer resin film)” is a resin film formed on the first resin film 10, and is formed using the acid transfer resin film forming composition of the present invention. It is. As described above, the acid transfer resin film is formed using the acid transfer resin film forming composition, and contains the radiation-sensitive acid generator (A) and the polymer (B). Therefore, when the second resin film is exposed, the acid generator (A) can generate an acid in the second resin film, and the generated acid is generated by the action of the polymer (B). Unnecessary diffusion in the resin film is prevented, and unintended acid transfer (acid diffusion) to the first resin film can also be prevented.

  And the acid in a 2nd resin film can be transcribe | transferred to a 1st resin film as needed by performing the transcription | transfer process mentioned later. The acid transferred to the first resin film dissociates the acid-dissociable group from the acid-dissociable group-containing resin contained in the first resin film (releases the protecting group), and the portion of the first resin film (first The acid transfer portion of the resin film can be alkali-soluble. As a result, a pattern in which an alkali-soluble portion and an alkali-insoluble portion are present is formed on the first resin film. Furthermore, after that, by developing the first resin film with an alkali developer or the like as necessary, the alkali-soluble portion can be removed, and a pattern consisting of only the alkali-insoluble portion can be formed.

The method for forming the second resin film is not particularly limited, and the means for applying the composition for forming the acid transfer resin film is not particularly limited. For example, suitable application such as spin coating, cast coating, roll coating, etc. Means are mentioned.
Furthermore, after applying the composition for forming an acid transfer resin film, if necessary, the second resin film (acid transfer resin film) is formed by volatilizing the solvent in the coating film by pre-baking (PB). May be. The heating conditions for this pre-baking are appropriately selected depending on the composition of the composition for forming an acid transfer resin film, but the heating temperature is usually about 30 to 150 ° C, preferably 50 to 130 ° C. Furthermore, the heating time is usually 30 to 300 seconds, preferably 60 to 180 seconds.
In addition, the thickness of the second resin film formed on the first resin film is not particularly limited, but is usually preferably 1 to 10000 nm, more preferably 5 to 800 nm, and more preferably 10 to 500 nm. Is more preferable.

[1-2] Exposure step (II)
The exposure step (II) is a step of exposing the second resin film through a mask to generate an acid in the second resin film. Thereby, as illustrated in FIG. 1, the exposed portion of the second resin film 20 becomes the acid generation portion 21.
The type of radiation used for exposure is not particularly limited, and ultraviolet rays, deep ultraviolet rays (KrF excimer laser, ArF excimer laser, F ₂ excimer laser, etc.) are used depending on the type of acid generator contained in the second resin film. Including), X-rays, electron beams, γ-rays, molecular beams, ion beams, and the like. Furthermore, the exposure amount and the like are appropriately selected according to the type of acid generator contained in the second resin film.

[1-3] Acid transfer step (III)
The acid transfer step (III) is a step of transferring the acid generated in the second resin film to the first resin film. Thereby, as illustrated in FIG. 1, a part of the first resin film 10 corresponding to the acid generation site 21 becomes the acid transfer site 11.
The method for transferring the acid is not particularly limited. Specifically, (1) a method for transferring by heating, (2) a method for transferring by standing at room temperature, and (3) a transfer using osmotic pressure. The method etc. are mentioned. These methods may be used alone or in combination of two or more. Among these methods, (1) the method of transferring by heating is preferable because of excellent transfer efficiency.
The heating conditions for transferring by heating are not particularly limited, but the heating temperature is preferably 50 to 200 ° C, more preferably 70 to 150 ° C. Furthermore, the heating time is preferably 30 to 300 seconds, more preferably 60 to 180 seconds.
In addition, when transferring by heating, it may be completed by one heating depending on the above heating conditions, but as a result, two or more heatings may be performed so as to obtain the same result as the above heating conditions. it can.

Note that (2) the method of transferring by allowing to stand at room temperature is a method in which the acid generated in the second resin film is not heated and is usually left in a room temperature environment of 20 to 30 ° C. This is a method in which the material is naturally diffused into the first resin film and transferred.
Furthermore, (3) the method of transferring using the osmotic pressure is to generate an osmotic pressure difference of the acid component between the second resin film and the first resin film by using the acid concentration difference. In this transfer method, the acid in the second resin film is diffused into the first resin film at a higher diffusion rate than natural diffusion.

[1-4] Second resin film (acid transfer resin film) removing step (IV)
The second resin film removing step (IV) is a step of removing the second resin film. That is, it is a step of removing the second resin film and exposing the first resin film having the acid transferred under the layer.
The removal may be performed by any method, but is usually performed by dissolving the second resin film with an organic solvent. This organic solvent dissolves the second resin film but does not dissolve the first resin film to which the acid has been transferred. Since the second resin film contains the iminosulfonate-based radiation sensitive acid generator (A) as an acid generator as described above, it can be easily removed and the second resin film does not remain and is removable. Especially good.

  The organic solvent used for removing the second resin film is preferably selected as appropriate depending on the resin composition of the second resin film and the first resin film, and the first resin film is not dissolved and the second resin film is dissolved. Any organic solvent can be used. Specific examples include acetonitrile, acetone, tetrahydrofuran, pyridine and the like. These organic solvents may use only 1 type and may use 2 or more types together. Among these, when acetonitrile is used, excellent removability by using the acid generator (A) is particularly easily obtained, and the effects of the present invention can be better obtained.

  In the pattern forming method of the present invention, by performing a series of steps from the second resin film step (I) to the second resin film removal step (IV) in this order, the portion where the acid is transferred and the acid are transferred. The pattern consists of a portion that is not transferred. And if necessary, the development step (V) can be further performed. When the development step (V) is performed, the portion (11 in FIG. 1) to which the acid obtained in the steps up to (IV) has been transferred is formed from the first resin film (10 in FIG. 1). As a result of the removal, a pattern (12 in FIG. 1) composed of the remaining portion of the first resin film and the portion from which the first resin film has been removed is formed.

[1-5] Development step (V)
The developing step (V) is a step of developing the first resin film using an alkaline developer after the second resin film removing step. That is, as illustrated in FIG. 1, this is a step of obtaining the pattern 12 by removing the acid transfer site 11 formed in the first resin film 10.

Examples of the alkaline developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, 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] A solution in which at least one of alkaline compounds such as 5-nonene is dissolved in a solvent.
Although the density | concentration of the alkaline compound contained in an alkaline developing solution is not specifically limited, 0.1-5 mass% is preferable and 0.3-3 mass% is still more preferable.

Moreover, the solvent which comprises the said alkaline developing solution is although it does not specifically limit, Water and / or an organic solvent are mentioned. Among these, 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, n- Alcohols such as propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, 1,4-hexanedimethylol; ethers such as tetrahydrofuran and dioxane And the like; 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 use only 1 type and may use 2 or more types together.
Further, an appropriate amount of a surfactant or the like can be added to the alkaline developer.

  In the pattern forming method of the present invention, steps other than the development step (V) may not be provided, but other steps may be provided. Examples of the other steps include a water washing step of washing the first resin film (the portion remaining after the portion of the first resin film where the acid has been transferred is removed) after the developing step.

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

[1] Preparation of first resin film forming composition As a monomer for forming an acid-dissociable group-containing resin, bis- (4-methoxyphenyl) -benzyl acrylate, phenol is used as a monomer having an acid-dissociable group. P-Isopropenylphenol was used as a monomer having a functional hydroxyl group, and p-hydroxyphenylmethacrylamide, hydroxyethyl acrylate and phenoxypolyethylene glycol acrylate were used as other monomers.

Each monomer bis- (4-methoxyphenyl) -benzyl acrylate 20 g, p-isopropenyl phenol 30 g, p-hydroxyphenyl methacrylamide 20 g, hydroxyethyl acrylate 20 g, and phenoxypolyethylene glycol acrylate 10 g, propylene glycol 120 g of monomethyl ether acetate (solvent) was mixed and stirred to prepare a uniform solution. Thereafter, the obtained solution was bubbled with nitrogen gas for 30 minutes. Next, 4 g of 2,2′-azobisisobutyronitrile (AIBN) was added as a polymerization initiator, and polymerization was carried out for 3 hours while maintaining the reaction temperature at 70 ° C. while continuing bubbling with nitrogen gas. Next, 1 g of AIBN was further added and reacted for 3 hours, and then reacted at 100 ° C. for 1 hour to complete the polymerization. Thereafter, the obtained reaction solution and a large amount of hexane were mixed to coagulate the product in the reaction solution. Then, after the coagulated product was redissolved in tetrahydrofuran, the operation of coagulation with hexane was repeated several times to remove unreacted monomers and dried at 50 ° C. under reduced pressure to obtain an acid-dissociable group-containing resin. .
The yield of the obtained acid-dissociable group-containing resin was 95%, Mw was 15,000, and Mw / Mn was 2.5.

  Thereafter, the obtained acid-dissociable group-containing resin (100 parts by mass), NBX-15 (manufactured by Neos) (0.05 parts by mass) as a surfactant, and propylene glycol monomethyl ether acetate (2000 parts by mass) as a solvent. After mixing and stirring to obtain a uniform solution, this solution was filtered through a capsule filter having a pore size of 0.5 μm to obtain a first resin film-forming composition.

In addition, the measurement and evaluation in the said synthesis | combination were performed in the following way. The same applies to each synthesis described later.
Gel permeation based on monodisperse polystyrene using GPC columns (2 G2000HXL, 1 G3000HXL, 1 4000 HXL) manufactured by Tosoh Corporation under the analysis conditions of a flow rate of 1.0 ml / min, elution solvent tetrahydrofuran, and column temperature of 40 ° C. It was measured by an association chromatography (GPC). Further, the degree of dispersion Mw / Mn was calculated from the measurement results.

[2] Preparation of composition for forming acid transfer resin film (Examples 1 to 10 and Comparative Examples 1 to 4)
(1) Polymer (B)
<Polymer B1>
In this synthesis example 1, N, N-dimethylacrylamide represented by the following formula (12) is used as a monomer (Bm1) for introducing the structural unit represented by the formula (1). In this example, methyl methacrylate is used as the monomer (Bm2) for introducing the structural unit represented by 2).

5 g of N, N-dimethylacrylamide (monomer Bm1, manufactured by Kojin Co., Ltd.) in a 500 mL beaker (5 mol% when the total of monomer Bm1 and monomer Bm2 is 100 mol%), methyl 95 g of methacrylate (monomer Bm2, manufactured by Mitsubishi Materials Corporation) (95 mol% when the total of monomer Bm1 and monomer Bm2 is 100 mol%), 2,2′-azobisisobutyro Nitrile (polymerization initiator) 3.0 g was charged and stirred until the polymerization initiator was dissolved to obtain a uniform solution. Separately, 150 g of propylene glycol monomethyl ether acetate (solvent) was charged into a flask equipped with a nitrogen-substituted dry ice / methanol refluxer, gently stirred and heated to 80 ° C. Then, the said solution was dripped little by little over 2 hours at 80 degreeC. After the dropping, polymerization was further performed at 80 ° C. for 3 hours, and then the temperature was raised to 100 ° C. and stirred for 1 hour to complete the polymerization. Thereafter, the obtained reaction solution was dropped into a large amount of cyclohexane to solidify the product. Next, the obtained coagulated product was washed with water, redissolved in tetrahydrofuran having the same mass as the coagulated product, and dropped into a large amount of cyclohexane to be coagulated again. After performing this re-dissolution and solidification cycle three times in total, the obtained solidified product was vacuum dried at 40 ° C. for 48 hours to obtain a polymer B1.
The yield of the obtained polymer B1 was 90%, Mw was 11,000, and Mw / Mn was 2.3. The polymer B1 is a resin having a structural unit represented by the formula (1).

<Polymer B2>
In Synthesis Example 2, 10 g of N, N-dimethylacrylamide (Monomer Bm1, manufactured by Kojin Co., Ltd.) in Synthesis Example 1 (the total amount of monomer Bm1 and monomer Bm2 was 100 mol%). 10 mol% in the case), 90 g of methyl methacrylate (monomer Bm2, manufactured by Mitsubishi Materials Corporation) (90 mol% when the total of monomer Bm1 and monomer Bm2 is 100 mol%), In the same manner as in Synthesis Example 1, a polymer B2 was obtained.
Mw of the obtained polymer B2 was 10,000. The polymer B2 is a resin having a structural unit represented by the formula (1).

<Polymer B3>
In Synthesis Example 3, 20 g of N, N-dimethylacrylamide (monomer Bm1, manufactured by Kojin Co., Ltd.) in Synthesis Example 1 (the total amount of monomer Bm1 and monomer Bm2 was 100 mol%). 20 mol%), 80 g of methyl methacrylate (monomer Bm2, manufactured by Mitsubishi Materials Corporation) (80 mol% when the total of monomer Bm1 and monomer Bm2 is 100 mol%), In the same manner as in Synthesis Example 1, a polymer B3 was obtained.
Mw of the obtained polymer B3 was 9,000. The polymer B3 is a resin having a structural unit represented by the formula (1).

<Polymer B4>
The following acrylic polymer (B4) was synthesized as a comparative polymer not corresponding to the polymer (B) in the acid transfer resin film-forming composition of the present invention.
30 g of p-isopropenylphenol (manufactured by Mitsui Chemicals), 35 g of isobornyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.), 5 g of phenoxypolyethylene glycol acrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “P-200A”), Hydroxyethyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.) 15 g and p-hydroxyphenyl methacrylamide (manufactured by Osaka Organic Chemical Industry Co., Ltd.) 15 g were mixed with propylene glycol monomethyl ether acetate 120 g and stirred to obtain a uniform solution. Prepared. After bubbling this solution with nitrogen gas for 30 minutes, 3 g of dimethyl-2,2′-azobisisobutyrate (V-601) was added, and 0.2 g of t-dodecyl mercaptan was added as a chain transfer agent. While the bubbling with nitrogen gas was continued, the reaction temperature was maintained at 70 ° C. and polymerization was performed for 3 hours. Thereafter, 1.5 g of the above V-601 was further added and reacted for 3 hours, and then the temperature was raised to 80 ° C. for polymerization for 2 hours, and further reacted at 100 ° C. for 1 hour to complete the polymerization. Thereafter, the reaction solution was mixed with a large amount of hexane to coagulate the produced polymer. Next, after the polymer was redissolved in tetrahydrofuran, the operation of coagulating with hexane was repeated several times to remove unreacted monomers and dried at 50 ° C. under reduced pressure to obtain polymer B4. Mw of the obtained polymer B4 was 12,000. The polymer B4 is a resin that does not have the structural unit represented by the formula (1).

The relationship between the blend of each monomer in the polymer B1 to the polymer B3 and the polymer B4 is as follows.

酸発生剤Ａ２〔下記式（６−２）〕；チバ・ジャパン株式会社製、品名「ＰＡＧ１０８」

酸発生剤Ａ３〔下記式（６−３）〕；チバ・ジャパン株式会社製、品名「ＰＡＧ１２１」

酸発生剤Ａ４〔下記式（１３）〕；みどり化学株式会社製、品名「ＮＡＩ−１０６」

(2) Mixing with other components As the acid generator (A), the following acid generators A1 to A3 were used, and further, the following A4 was used as the acid generator of the comparative example.
Acid generator A1 [following formula (6-1)]; manufactured by Ciba Japan Co., Ltd., product name “PAG103”

Acid generator A2 [Formula (6-2) below]; manufactured by Ciba Japan Co., Ltd., product name “PAG108”

Acid generator A3 [Formula (6-3) below]; manufactured by Ciba Japan Co., Ltd., product name “PAG121”

Acid generator A4 [following formula (13)]; product name “NAI-106” manufactured by Midori Chemical Co., Ltd.

Moreover, the said polymer B1 was used as a polymer (B) and the said polymer B1 as a polymer of a comparative example as a polymer (B).
Furthermore, the following solvent C1 and solvent C2 were used as the solvent (C).
Solvent C1; Propylene glycol monomethyl ether acetate Solvent C2; γ-butyrolactone Further, as the additive [surfactant (D)], a trade name “DYNAFLOW” manufactured by JSR Corporation was used.

  The acid generators A1 to A4 (15 parts by mass or 30 parts by mass), the polymers B1 to B4 (100 parts by mass), the solvent (500 to 1500 parts by mass) so that these four components have the composition shown in Table 2. Then, a surfactant (0.05 parts by mass) was mixed and stirred to obtain a uniform solution (concentration of solids shown in Table 2). This solution was filtered through a capsule filter having a pore size of 0.5 μm to obtain 14 types of compositions for forming an acid transfer resin film (Examples 1 to 10 and Comparative Examples 1 to 4).

尚、表２内の「＊」は、本発明の範囲外を示す。

In addition, “*” in Table 2 indicates outside the scope of the present invention.

[3] Pattern Formation (1) First Resin Film Formation Step The first resin film formation composition obtained in [1] above was applied to the surface of a silicon substrate using a spin coater. Then, it heated at 110 degreeC on the hotplate for 1 minute, and formed the 1st resin film with a thickness of 200 nm.

(2) Acid transfer film forming step (I)
Using the spin coater on the surface of the first resin film obtained in (1) above, the composition for forming an acid transfer film according to any one of Examples 1 to 10 and Comparative Examples 1 to 4 obtained in [2] above The object was applied. Then, it heated on 110 degreeC on the hotplate for 1 minute, and formed the 150-nm-thick acid transfer film.

(3) Exposure process (II)
Ultraviolet light of 100 to 1000 mJ / cm ² using a super high pressure mercury lamp (manufactured by OSRAM, model “HBO”, output 1,000 W) on the surface of the acid transfer film obtained in (2) above through a pattern mask. Irradiated with light. The amount of exposure was confirmed with an illuminometer (a device in which the model “UV-M10” (illuminometer) was connected to the model “probe UV-35” (receiver) manufactured by Oak Manufacturing Co., Ltd.).

(4) Acid transfer step (III)
The laminate obtained up to (3) was heat-treated at 110 ° C. for 1 minute on a hot plate.

(5) Acid transfer film removal step (IV)
The laminate obtained up to (4) was immersed in acetonitrile for 30 seconds to remove only the acid transfer resin film.

(6) Development step (V)
Development was performed by immersing the laminate obtained up to (5) above in a 2.38 mass% tetramethylammonium hydroxide aqueous solution at room temperature for 1 minute. Thereafter, it was washed with running water and blown with nitrogen to obtain a pattern.
Hereinafter, the substrate on which this pattern is formed is referred to as a “patterning substrate”.

[4] Sensitivity evaluation The patterning substrate was observed with an optical microscope, and sensitivity evaluation was performed. Here, the sensitivity refers to the minimum exposure amount at which a line / space = 50/50 μm pattern is resolved without residue, and the exposure amount is defined as “optimum exposure amount”. The results are shown in Table 3.

[5] Dimensional evaluation The patterning substrate processed with the optimum exposure dose was observed with a scanning electron microscope, and the dimension of the pattern of line / space = 50/50 μm was measured. Here, the dimension evaluation is evaluated by a deviation of the measurement dimension from the mask dimension, and 0 to 5 μm is evaluated as “◯”, and 5 μm or more is evaluated as “X”. The results are shown in Table 3.

[6] Evaluation of Removability of Acid Transfer Resin Film (5) The laminate after the acid transfer film removal step (IV) is completed, and the first resin film after removal of the second resin film (acid transfer resin film). After enlarging the surface of the resin film 50 times with an optical microscope, 10 different randomly selected visual fields (1 cm × 1 cm) were visually observed, and the presence or absence of the second resin film on the surface of the first resin film Was observed. As a result, “◯” indicates that no residue was observed in any visual field, and “×” indicates that a residue was observed in one or more visual fields. The results are shown in Table 3.

It is explanatory drawing which illustrates the pattern formation method of this invention typically.

(I); a second resin film (acid transfer resin film) forming step;
(II); exposure step;
(III); transfer step,
(IV); a second resin film (acid transfer film) removing step,
(V): development process,
10; first resin film (patterned resin film), 11; acid transfer site,
20; second resin film (acid transfer resin film), 21; acid generation site, 30; mask.

Claims (5)

A composition for forming an acid transfer resin film, comprising: (A) an iminosulfonate-based radiation-sensitive acid generator; and (B) a polymer having a structural unit represented by the following formula (1).

Wherein (1), R ¹ represents a hydrogen atom or a methyl group. R ² and R ³ each independently represent a hydrogen atom, a linear or branched hydrocarbon group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group having 3 to 10 carbon atoms. R ² and R ³ are bonded to each other to form a 3- to 10-membered monocyclic heterocycle having at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom. Also good. ] The composition for forming an acid transfer resin film according to claim 1, wherein the polymer having the structural unit represented by the formula (1) further has a structural unit represented by the following formula (2).

[In formula (2), R ¹ represents a hydrogen atom or a methyl group. R ² represents a monovalent organic group. ] The composition for forming an acid transfer resin film according to claim 1 or 2, comprising a compound represented by the following formula (3) as the (A) iminosulfonate-based radiation-sensitive acid generator.

[In Formula (3), R ¹ is an alkyl group having 1 to 14 carbon atoms, an aromatic group having 6 to 20 carbon atoms, an alicyclic hydrocarbon group having 4 to 20 carbon atoms, or at least one of these groups. An organic group in which two hydrogen atoms are substituted with a polar group other than an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a hydrocarbon group. ]   An acid transfer resin film comprising the acid transfer resin film forming composition according to any one of claims 1 to 3. (I) On the first resin film containing a resin having an acid dissociable group and not containing a radiation sensitive acid generator,
A second resin film forming step of forming a second resin film as an acid transfer resin film using the acid transfer resin film forming composition according to any one of claims 1 to 3;
(II) exposing the second resin film through a mask and generating an acid in the second resin film;
(III) an acid transfer step of transferring the acid generated in the second resin film to the first resin film;
(IV) A pattern forming method comprising: a second resin film removing step of removing the second resin film in this order.

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