JP5223260B2 - Salt for acid generator of chemically amplified resist composition - Google Patents

Description

  The present invention relates to a salt used as an acid generator contained in a chemically amplified resist composition used in a chemically amplified resist composition used for semiconductor microfabrication.

A chemically amplified resist composition used for fine processing of a semiconductor using a lithography technique contains an acid generator composed of a compound that generates an acid upon exposure.
In semiconductor microfabrication, high resolution and high sensitivity are desirable, and a chemically amplified resist composition is required to exhibit high resolution and high sensitivity.

  Recently, a chemically amplified resist composition comprising triphenylsulfonium 1-adamantanemethoxycarbonyldifluoromethanesulfonate (salt) and p-tolyldiphenylsulfonium perfluorooctanesulfonate (salt) as an acid generator has been proposed. However, there has been a demand for a salt serving as an acid generator that provides a chemically amplified resist composition that exhibits higher resolution and is highly sensitive (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2004-4561

  An object of the present invention is to provide a salt as an acid generator that provides a chemically amplified resist composition that exhibits high resolution and high sensitivity.

  Therefore, as a result of intensive studies on the salt used as the acid generator contained in the chemically amplified resist composition in order to solve the above problems, the present inventors have found that a specific salt having an ester residue is present. The present inventors have found that the present invention can be an acid generator that provides a chemically amplified resist composition that exhibits high resolution and high sensitivity, and has completed the present invention.

（式（Ｉａ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、Ａは−ＯＨ又は−Ｙ¹−ＯＨを表し、ｎは１〜９の整数を表す。Ｙ¹は直鎖状もしくは分岐状の炭素数１〜６のアルキレン基を表す。） That is, the present invention provides a salt represented by the formula (Ia).

(In Formula (Ia), P ^{1 to} P ³ each independently represent a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms, provided that The number of phenyl groups directly bonded to the sulfur atom is not more than 2. When any one of P ^{1 to} P ³ is an alkyl group, it is a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a carbon group having 3 to 12 carbon atoms. One or more cyclic hydrocarbon groups may be contained as a substituent, and when any of P ^{1 to} P ³ is a cyclic hydrocarbon group, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or One or more alkoxy groups having 1 to 12 carbon atoms may be contained as a substituent, Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group, and A represents —OH. or represents -Y ¹ -OH, n is also .Y ¹ is linear represents an integer of 1-9 Or a branched alkylene group having 1 to 6 carbon atoms.)

（式（Ｉｂ）および式（Ｉｃ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、環Ｘ¹は環Ｘ¹の一部を形成するように記載された二つの炭素原子とともに形成する炭素数３〜３０の、式（Ｉｂ）においては＝Ｏと結合している、式（Ｉｃ）においては−ＯＨと結合している単環式または多環式炭化水素基を表す。式（Ｉｂ）および式（Ｉｃ）中の環Ｘ¹は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基、炭素数１〜６のヒドロキシアルキル基、水酸基又はシアノ基の一つ以上を置換基として含んでいてもよい。） The present invention also provides a salt represented by the formula (Ib) or (Ic).

(In Formula (Ib) and Formula (Ic), P ^{1 to} P ³ are each independently a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms. However, the number of phenyl groups directly bonded to the sulfur atom is not more than 2. When any of the P ^{1 to} P ³ is an alkyl group, a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or carbon One or more of cyclic hydrocarbon groups of 3 to 12 may be contained as a substituent, and when any of P ^{1 to} P ³ is a cyclic hydrocarbon group, a hydroxyl group, 12 or more alkyl groups having 1 to 12 carbon atoms may be included as substituents, and Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group. , two rings X ¹ has been described so as to form a part of the ring X ¹ carbon A monocyclic or polycyclic hydrocarbon group having 3 to 30 carbon atoms, which is formed together with a child, bonded to ═O in the formula (Ib), or bonded to —OH in the formula (Ic) Ring X ^{1 in} formula (Ib) and formula (Ic) is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. (It may contain one or more of a hydroxyalkyl group, a hydroxyl group or a cyano group as a substituent.)

（式（Ｉｄ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、環Ｘ²は炭素数３〜３０の単環式または多環式炭化水素基を表し、環構造中にエステル結合を有する。ｍは０〜１２の整数を表し、式（Ｉｄ）中の環Ｘ²は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基、炭素数１〜６のヒドロキシアルキル基、水酸基又はシアノ基の一つ以上を置換基として含んでいてもよい。） The present invention also provides a salt represented by the formula (Id).

(In the formula (Id), P ^{1 to} P ³ each independently represent a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms, provided that The number of phenyl groups directly bonded to the sulfur atom is not more than 2. When any one of P ^{1 to} P ³ is an alkyl group, it is a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a carbon group having 3 to 12 carbon atoms. One or more cyclic hydrocarbon groups may be contained as a substituent, and when any of P ^{1 to} P ³ is a cyclic hydrocarbon group, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or One or more of the alkoxy groups having 1 to 12 carbon atoms may be contained as a substituent, Q ¹ and Q ² each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms, and the ring X ² is Represents a monocyclic or polycyclic hydrocarbon group having 3 to 30 carbon atoms, .M having ester bond represents an integer of 0 to 12, the ring X ² is an alkyl group having 1 to 6 carbon atoms in the formula (Id), alkoxy group having 1 to 6 carbon atoms, perfluoro 1 to 4 carbon atoms One or more of an alkyl group, a C1-C6 hydroxyalkyl group, a hydroxyl group or a cyano group may be contained as a substituent.)

（式（Ｉｅ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、環Ｘ³は炭素数６〜３０の３環以上の多環式炭化水素基を表す。ｌは１〜１２の整数を表し、式（Ｉｅ）中の環Ｘ³は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基又はシアノ基の一つ以上を置換基として含んでいてもよい。） The present invention also provides a salt represented by the formula (Ie).

(In Formula (Ie), P ^{1 to} P ³ each independently represent a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms, provided that The number of phenyl groups directly bonded to the sulfur atom is not more than 2. When any one of P ^{1 to} P ³ is an alkyl group, it is a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a carbon group having 3 to 12 carbon atoms. One or more cyclic hydrocarbon groups may be contained as a substituent, and when any of P ^{1 to} P ³ is a cyclic hydrocarbon group, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or One or more alkoxy groups having 1 to 12 carbon atoms may be contained as a substituent, Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group, and ring X ³ is Represents a polycyclic hydrocarbon group having 3 or more rings having 6 to 30 carbon atoms, where l is 1 to 12 Represents an integer, and ring X ³ in formula (Ie) is substituted with one or more alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, perfluoroalkyl groups having 1 to 4 carbon atoms, or cyano groups. It may be included as a group.)

  The present invention also provides an acid generator containing a salt represented by any one of formulas (Ia) to (Ie) as an active ingredient.

  The present invention also provides a resin composition containing a salt represented by any one of formulas (Ia) to (Ie) and a resin, the resin having an acid-labile group, and an alkaline aqueous solution. Provided is a resin composition characterized in that it is an insoluble or hardly soluble resin, and the resin that has reacted with an acid is a resin that can be dissolved in an alkaline aqueous solution.

  Furthermore, the present invention provides a chemically amplified resist composition comprising the resin compound and a basic organic compound.

  By using the salt of the present invention as an acid generator, a chemically amplified resist composition having high resolution and high sensitivity can be produced, so that the present invention is extremely useful industrially.

ここで式（Ｉａ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基（環としては、単環でも多環でもよく、二重結合を含んでいても芳香環でもよい。）を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい（Ｐ¹〜Ｐ³の炭素数には置換基の炭素数も含まれる。）。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、Ａは−ＯＨ又は−Ｙ¹−ＯＨを表し、ｎは１〜９の整数を表す。Ｙ¹は直鎖状もしくは分岐状の炭素数１〜６のアルキレン基を表す。
Ｑ¹、Ｑ²としてはそれぞれ独立にフッ素原子または−ＣＦ₃である場合が好ましく、ｎとしては１〜２である場合が好ましい。
Ｙ¹としては、例えば、次の（Ｙ¹−１）〜（Ｙ¹−１２）などが挙げられ、中でも、（Ｙ¹−１）及び（Ｙ¹−２）が、製造が容易であることから好ましい。 The first salt of the present invention is represented by the formula (Ia).

In formula (Ia), P ^{1 to} P ³ are each independently a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms (as a ring). , May be monocyclic or polycyclic, and may contain a double bond or an aromatic ring). However, no more than two phenyl groups are directly bonded to the sulfur atom. When any of the P ^{1 to} P ³ is an alkyl group, it contains one or more of a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a cyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent. In the case where any of P ^{1 to} P ³ is a cyclic hydrocarbon group, one or more of a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms may be substituted. (The carbon number of P ^{1 to} P ³ includes the carbon number of the substituent). Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group, A represents —OH or —Y ¹ —OH, and n represents an integer of 1 to 9. Y ¹ represents a linear or branched alkylene group having 1 to 6 carbon atoms.
Q ¹ and Q ² are preferably each independently a fluorine atom or —CF ₃ , and n is preferably 1 to 2.
Examples of Y ¹ include the following (Y ¹ -1) to (Y ¹ -12), among which (Y ¹ -1) and (Y ¹ -2) are easy to produce. To preferred.

Specific examples of the anion moiety of the salt represented by the formula (Ia) include anions represented by the following formula.

（式（ａ−Ｉ）中、Ａ及びｎは前記と同じ意味を表す。）、式（ａ−II）

（式（ａ−II）中、Ｑ¹、Ｑ²は前記と同じ意味を表し、Ｍは、Ｌｉ、Ｎａ、Ｋ、又はＡｇを表す。）で示されるカルボン酸とをエステル化反応させ、得られた式（ａ−III）で示される塩と、

（式（ａ−III）中、Ｑ¹、Ｑ²、Ａ、ｎおよびＭは、それぞれ前記と同じ意味を表す。）式（ａ−IＶ）で示される化合物とを反応させて製造することができる。

（式（ａ−IＶ）中、Ｐ¹〜Ｐ³は前記と同じ意味を表し、ＺはＦ、Ｃｌ、Ｂｒ、Ｉ、ＢＦ₄、ＡｓＦ₆、ＳｂＦ₆、ＰＦ₆又はＣｌＯ₄を表す。） The salt represented by the formula (Ia) is an alcohol represented by the formula (a-I)

(In formula (a-I), A and n represent the same meaning as described above), formula (a-II)

(In formula (a-II), Q ¹ and Q ² represent the same meaning as described above, and M represents Li, Na, K, or Ag.) A salt of the formula (a-III)

(In formula (a-III), Q ¹ , Q ² , A, n and M each have the same meaning as described above.) The compound represented by formula (a-IV) can be reacted to produce the compound. it can.

(In the formula (a-IV), P ^{1 to} P ³ represent the same meaning as described above, and Z represents F, Cl, Br, I, BF ₄ , AsF ₆ , SbF ₆ , PF ₆ or ClO _4. )

ここで式（Ｉｂ）および式（Ｉｃ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基（環としては、単環でも多環でもよく、二重結合を含んでいても芳香環でもよい。）を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい（Ｐ¹〜Ｐ³の炭素数には置換基の炭素数も含まれる。）。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、環Ｘ¹は環Ｘ¹の一部を形成するように記載された二つの炭素原子とともに形成する炭素数３〜３０の、式（Ｉｂ）においては＝Ｏと結合している、式（Ｉｃ）においては−ＯＨと結合している単環式または多環式炭化水素基を表す。式（Ｉｂ）および式（Ｉｃ）中の環Ｘ¹は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基、炭素数１〜６のヒドロキシアルキル基、水酸基又はシアノ基の一つ以上を置換基として含んでいてもよい。
Ｑ¹、Ｑ²としてはそれぞれ独立にフッ素原子または−ＣＦ₃である場合が好ましい。 The second salt of the present invention is represented by the formula (Ib) or the formula (Ic).

Here, in formula (Ib) and formula (Ic), P ^{1 to} P ³ are each independently a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon having 3 to 30 carbon atoms. Represents a group (the ring may be monocyclic or polycyclic and may contain a double bond or an aromatic ring). However, no more than two phenyl groups are directly bonded to the sulfur atom. When any of the P ^{1 to} P ³ is an alkyl group, it contains one or more of a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a cyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent. In the case where any of P ^{1 to} P ³ is a cyclic hydrocarbon group, one or more of a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms may be substituted. (The carbon number of P ^{1 to} P ³ includes the carbon number of the substituent). Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group, and ring X ¹ is carbon formed together with two carbon atoms described so as to form part of ring X ^1. In the formula (Ib), a monocyclic or polycyclic hydrocarbon group that is bonded to ═O, or is bonded to —OH in the formula (Ib) is represented by the formula (Ib). Ring X ^{1 in} formula (Ib) and formula (Ic) is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, or a hydroxy group having 1 to 6 carbon atoms. One or more of an alkyl group, a hydroxyl group or a cyano group may be contained as a substituent.
Q ¹ and Q ² are preferably each independently a fluorine atom or —CF ₃ .

Examples of such ring X ¹ include a monocyclic or polycyclic hydrocarbon group containing a cycloalkyl skeleton having 4 to 8 carbon atoms, an adamantyl skeleton, and a norbornane skeleton. Any one of these skeletons is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, a hydroxyl group, or a cyano group. The above may be included as a substituent.

Specific examples of the anion moiety of the salt represented by the formula (Ib) or the formula (Ic) include anions represented by the following formulas.

（式（ｂ−Ｉ）および式（ｃ−Ｉ）中、環Ｘ¹は前記と同じ意味を表す。）
式（ｂ−II）

（式（ｂ−II）中、Ｑ¹、Ｑ²およびＭは前記と同じ意味を表す。）
で示されるカルボン酸とをエステル化反応させ、得られたそれぞれ式（ｂ−III）または式（ｃ−III）で示される塩と、

（式（ｂ−III）および式（ｃ−III）中、Ｑ¹、Ｑ²、Ｘ¹およびＭは、それぞれ前記と同じ意味を表す。）
式（ｂ−IＶ）で示される化合物とを反応させて製造することができる。

（式（ｂ−IＶ）中、Ｐ¹〜Ｐ³は前記と同じ意味を表し、Ｚは前記と同じ意味を表す。） The salt represented by the formula (Ib) and the salt represented by the formula (Ic) are respectively an alcohol represented by the formula (b-I) or the formula (c-I),

(In formula (b-I) and formula (c-I), ring X ¹ represents the same meaning as described above.)
Formula (b-II)

(In formula (b-II), Q ¹ , Q ² and M represent the same meaning as described above.)
An esterification reaction with the carboxylic acid represented by formula (b-III) or the salt represented by formula (c-III),

(In Formula (b-III) and Formula (c-III), Q ¹ , Q ² , X ¹ and M each have the same meaning as described above.)
It can be produced by reacting a compound represented by the formula (b-IV).

(In formula (b-IV), P ^{1 to} P ³ represent the same meaning as described above, and Z represents the same meaning as described above.)

ここで式（Ｉｄ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基（環としては、単環でも多環でもよく、二重結合を含んでいても芳香環でもよい。）を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい（Ｐ¹〜Ｐ³の炭素数には置換基の炭素数も含まれる。）。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、環Ｘ²は炭素数３〜３０の単環式または多環式炭化水素基を表し、環構造中にエステル結合を有する。ｍは０〜１２の整数を表す。式（Ｉｄ）中の環Ｘ²は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基、炭素数１〜６のヒドロキシアルキル基、水酸基又はシアノ基の一つ以上を置換基として含んでいてもよい。
なお、環Ｙの炭素数にはエステル結合（−ＣＯ−Ｏ−）の炭素を含む（以下も同じ）。
Ｑ¹、Ｑ²としてはそれぞれ独立にフッ素原子または−ＣＦ₃である場合が好ましい。 The third salt of the present invention is represented by the formula (Id).

Here, in formula (Id), P ^{1 to} P ³ are each independently a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms (as a ring) , May be monocyclic or polycyclic, and may contain a double bond or an aromatic ring). However, no more than two phenyl groups are directly bonded to the sulfur atom. When any of the P ^{1 to} P ³ is an alkyl group, it contains one or more of a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a cyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent. In the case where any of P ^{1 to} P ³ is a cyclic hydrocarbon group, one or more of a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms may be substituted. (The carbon number of P ^{1 to} P ³ includes the carbon number of the substituent). Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group, ring X ² represents a C 3-30 monocyclic or polycyclic hydrocarbon group, Has an ester bond. m represents an integer of 0 to 12. Ring X ² in formula (Id) is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, a hydroxyl group, or One or more cyano groups may be included as a substituent.
In addition, the carbon number of the ring Y includes the carbon of the ester bond (—CO—O—) (the same applies hereinafter).
Q ¹ and Q ² are preferably each independently a fluorine atom or —CF ₃ .

式（IIａ）、式（IIｂ）および式（IIｃ）中、Ｙ²、Ｙ³、Ｙ⁴はそれぞれ独立に、アルキレン基又は無結合を表し、ｋは１〜４の整数を表し、ｊは０〜２の整数を表す。式（IIａ）、式（IIｂ）又は式（IIｃ）中の環は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基、炭素数１〜６のヒドロキシアルキル基、水酸基又はシアノ基の一つ以上を置換基として含んでいてもよい。 Examples of such ring X ² include a monovalent residue of a compound represented by formula (IIa), formula (IIb), or formula (IIc).

In formula (IIa), formula (IIb) and formula (IIc), Y ² , Y ³ and Y ⁴ each independently represents an alkylene group or no bond, k represents an integer of 1 to 4, and j represents 0. Represents an integer of ~ 2. The ring in formula (IIa), formula (IIb) or formula (IIc) is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, or 1 to 1 carbon atoms. One or more of 6 hydroxyalkyl groups, hydroxyl groups or cyano groups may be contained as a substituent.

Specific examples of the anion moiety of the salt represented by the formula (Id) include anions represented by the following formula.

（式（ｄ−Ｉ）中、環Ｘ²、ｍは前記と同じ意味を表す。）
式（ｄ−II）

（式（ｄ−II）中、Ｑ¹、Ｑ²およびＭは前記と同じ意味を表す。）
で示されるカルボン酸とをエステル化反応させ、得られた式（ｄ−III）で示される塩と、

（式（ｄ−III）中、Ｑ¹、Ｑ²、ｍ、Ｘ²およびＭはそれぞれ前記と同じ意味を表す。）
式（ｄ−IＶ）で示される化合物とを反応させて製造することができる。

（式（ｄ−IＶ）中、Ｐ¹〜Ｐ³は前記と同じ意味を表し、Ｚは前記と同じ意味を表す。） The salt represented by the formula (Id) includes an alcohol represented by the formula (d-I),

(In the formula (dl), the rings X ² and m have the same meaning as described above.)
Formula (d-II)

(In formula (d-II), Q ¹ , Q ² and M have the same meaning as described above.)
An esterification reaction with the carboxylic acid represented by formula (d-III),

(In formula (d-III), Q ¹ , Q ² , m, X ² and M each have the same meaning as described above.)
It can be produced by reacting a compound represented by the formula (d-IV).

(In formula (d-IV), P ^{1 to} P ³ represent the same meaning as described above, and Z represents the same meaning as described above.)

ここで式（Ｉｅ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖状もしくは分岐状の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基（環としては、単環でも多環でもよく、二重結合を含んでいても芳香環でもよい。）を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。当該Ｐ¹〜Ｐ³のいずれかがアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³のいずれかが環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい（Ｐ¹〜Ｐ³の炭素数には置換基の炭素数も含まれる。）。Ｑ¹、Ｑ²は互いに独立にフッ素原子又は炭素数１〜６のペルフルオロアルキル基を表し、環Ｘ³は炭素数６〜３０の３環以上の多環式炭化水素基を表す。ｌは１〜１２の整数を表す。式（Ｉｅ）中の環Ｘ³は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基又はシアノ基の一つ以上を置換基として含んでいてもよい。
Ｑ¹、Ｑ²としてはそれぞれ独立にフッ素原子または−ＣＦ₃である場合が好ましい。 The fourth salt of the present invention is represented by the formula (Ie).

Here, in formula (Ie), P ^{1 to} P ³ are each independently a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms (as a ring). , May be monocyclic or polycyclic, and may contain a double bond or an aromatic ring). However, no more than two phenyl groups are directly bonded to the sulfur atom. When any of the P ^{1 to} P ³ is an alkyl group, it contains one or more of a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a cyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent. In the case where any of P ^{1 to} P ³ is a cyclic hydrocarbon group, one or more of a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms may be substituted. (The carbon number of P ^{1 to} P ³ includes the carbon number of the substituent). Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group, and the ring X ³ represents a C 6-30 polycyclic hydrocarbon group having 3 or more rings. l represents an integer of 1 to 12. Ring X ³ in formula (Ie) contains one or more alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, perfluoroalkyl groups having 1 to 4 carbon atoms, or cyano groups as substituents. May be.
Q ¹ and Q ² are preferably each independently a fluorine atom or —CF ₃ .

式（IIIａ）および式（IIIｂ）中、Ｙ⁵、Ｙ⁶はそれぞれ独立に、アルキレン基又は酸素原子を表し、Ｙ⁶は無結合でもよい。式（IIIａ）又は式（IIIｂ）中の環は炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基又はシアノ基の一つ以上を置換基として含んでいてもよい。 As such ring X ³ , a monovalent residue of the compound represented by the formula (IIIa) or the formula (IIIb) is preferable.

In formula (IIIa) and formula (IIIb), Y ⁵ and Y ⁶ each independently represent an alkylene group or an oxygen atom, and Y ⁶ may be non-bonded. The ring in formula (IIIa) or formula (IIIb) is a substituent of one or more of an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, or a cyano group. May be included.

Specific examples of the anion moiety of the salt represented by the formula (Ie) include anions represented by the following formula.

（式（ｅ−Ｉ）中、Ｘ³及びｌは前記と同じ意味を表す。）
式（ｅ−II）

（式（ｅ−II）中、Ｑ¹、Ｑ²およびＭは前記と同じ意味を表す。）
で示されるカルボン酸とをエステル化反応させ、得られた式（ｅ−III）で示される塩と、

（式（ｅ−III）中、Ｑ¹、Ｑ²、Ｍ、ｌおよびＸ³は前記と同じ意味を表す。）
式（ｅ−IＶ）で示される化合物とを反応させて製造することができる。

（式（ｅ−IＶ）中、Ｐ¹〜Ｐ³は前記と同じ意味を表し、Ｚは前記と同じ意味を表す。） The salt of the formula (Ie) is an alcohol of the formula (e-I)

(In formula (e-I), X ³ and l represent the same meaning as described above.)
Formula (e-II)

(In formula (e-II), Q ¹ , Q ² and M represent the same meaning as described above.)
An esterification reaction with the carboxylic acid represented by formula (e-III),

(In formula (e-III), Q ¹ , Q ² , M, 1 and X ³ represent the same meaning as described above.)
It can be produced by reacting a compound represented by the formula (e-IV).

(In formula (e-IV), P ^{1 to} P ³ represent the same meaning as described above, and Z represents the same meaning as described above.)

Specific examples of the cation moiety of the salts represented by the formulas (Ia) to (Ie) include cations represented by the following formulas.

  Among the cations of the above formula, it is preferable that one or two are aryl groups.

（式（IＶａ）〜式（IＶｄ）中、Ｐ⁴〜Ｐ⁶は互いに独立に、直鎖状もしくは分岐状の炭素数１〜２０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。式中のＰ⁴〜Ｐ⁶は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよい。式中のＰ⁷〜Ｐ⁹は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基を表し、ｈ、ｇ、ｆはそれぞれ０〜５の整数を表す。） As the salt represented by the formula (Ia) of the present invention, among them, the acid generator that provides the chemically amplified resist composition in which the salt represented by the formula (IVa) to the formula (IVd) exhibits high resolution and high sensitivity. This is preferable.

(In the formulas (IVa) to (IVd), P ^{4 to} P ⁶ are each independently a linear or branched alkyl group having 1 to 20 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms. However, the number of phenyl groups directly bonded to the sulfur atom is not more than 2. In the formula, P ^{4 to} P ⁶ are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or carbon. One or more cyclic hydrocarbon groups having a number of 3 to 12 may be contained as a substituent, and P ^{7 to} P ⁹ in the formula are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, and a carbon number of 1 to 12 An alkoxy group or a C3-C12 cyclic hydrocarbon group, h, g and f each represents an integer of 0 to 5)

（式（IＶｅ）〜式（IＶｈ）中、Ｐ⁴〜Ｐ⁶は互いに独立に、直鎖状もしくは分岐状の炭素数１〜２０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。式中のＰ⁴〜Ｐ⁶は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよい。式中のＰ⁷〜Ｐ⁹は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基を表し、ｈ、ｇ、ｆはそれぞれ０〜５の整数を表す。） Further, as the salt represented by the formula (Ib) or the formula (Ic) of the present invention, among them, the salt represented by the formula (IVe) to the formula (IVh) is a chemically amplified resist having high resolution and high sensitivity. Since it becomes an acid generator which gives a composition, it is preferable.

(In the formulas (IVe) to (IVh), P ^{4 to} P ⁶ are each independently a linear or branched alkyl group having 1 to 20 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms. However, the number of phenyl groups directly bonded to the sulfur atom is not more than 2. In the formula, P ^{4 to} P ⁶ are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or carbon. One or more cyclic hydrocarbon groups having a number of 3 to 12 may be contained as a substituent, and P ^{7 to} P ⁹ in the formula are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, and a carbon number of 1 to 12 An alkoxy group or a C3-C12 cyclic hydrocarbon group, h, g and f each represents an integer of 0 to 5)

（式（IＶｉ）〜式（IＶｌ）中、Ｐ⁴〜Ｐ⁶は互いに独立に、直鎖状もしくは分岐状の炭素数１〜２０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。式中のＰ⁴〜Ｐ⁶は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよい。式中のＰ⁷〜Ｐ⁹は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基を表し、ｈ、ｇ、ｆはそれぞれ０〜５の整数を表す。） Further, as the salt represented by the formula (Id) of the present invention, among them, the salt represented by the formula (IVi) to the formula (IV1) is an acid that provides a chemically amplified resist composition that exhibits high resolution and high sensitivity. Since it becomes a generator, it is preferable.

(In the formulas (IVi) to (IVl), P ^{4 to} P ⁶ are each independently a linear or branched alkyl group having 1 to 20 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms. However, the number of phenyl groups directly bonded to the sulfur atom is not more than 2. In the formula, P ^{4 to} P ⁶ are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or carbon. One or more cyclic hydrocarbon groups having a number of 3 to 12 may be contained as a substituent, and P ^{7 to} P ⁹ in the formula are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, and a carbon number of 1 to 12 An alkoxy group or a C3-C12 cyclic hydrocarbon group, h, g and f each represents an integer of 0 to 5)

（式（IＶｍ）および式（IＶｎ）中、Ｐ⁴〜Ｐ⁶は互いに独立に、直鎖状もしくは分岐状の炭素数１〜２０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。ただし、硫黄原子に直接結合するフェニル基は二つ以下とする。式中のＰ⁴〜Ｐ⁶は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよい。式中のＰ⁷〜Ｐ⁹は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基を表し、ｈ、ｇ、ｆはそれぞれ０〜５の整数を表す。） Further, as the salt represented by the formula (Ie) of the present invention, among them, the salt represented by the formula (IVm) or the formula (IVn) exhibits a high resolution and a highly sensitive chemically amplified resist composition. Since it becomes a generator, it is preferable.

(In formula (IVm) and formula (IVn), P ^{4 to} P ⁶ are each independently a linear or branched alkyl group having 1 to 20 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms. However, the number of phenyl groups directly bonded to the sulfur atom is not more than 2. In the formula, P ^{4 to} P ⁶ are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or carbon. One or more cyclic hydrocarbon groups having a number of 3 to 12 may be contained as a substituent, and P ^{7 to} P ⁹ in the formula are a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, and a carbon number of 1 to 12 An alkoxy group or a C3-C12 cyclic hydrocarbon group, h, g and f each represents an integer of 0 to 5)

  The resin composition of the present invention is a resin composition containing a salt represented by any one of formulas (Ia) to (Ie) and a resin, and the resin has an acid-labile group, A resin that is insoluble or hardly soluble in an alkaline aqueous solution, and the resin that has reacted with an acid is a resin that can be dissolved in an alkaline aqueous solution.

  The salt represented by the formula (Ia) to the formula (Ie) is used as an acid generator, and the acid generated by exposure acts catalytically on a group in the resin which is unstable to the acid. The resin becomes soluble in an alkaline aqueous solution. Such a resin composition is suitable as a chemically amplified positive resist composition.

Examples of the acid labile group include a group having an alkyl ester in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, a group having a carboxylic acid ester such as an alicyclic ester, and a carbon atom adjacent to the oxygen atom. And a group having a lactone ring which is a quaternary carbon atom.
Here, the quaternary carbon atom means a carbon atom bonded to a substituent other than a hydrogen atom and not bonded to hydrogen, and an acid labile group includes a carbon atom adjacent to an oxygen atom. Is preferably a quaternary carbon atom bonded to three carbon atoms.

To illustrate a group having a carboxylic acid ester which is one of the acid labile group as R ester of -COOR, (-. The COO-C (CH ₃₎ referred in ₃ form a tert- butyl ester), tert -Alkyl ester in which the carbon atom adjacent to the oxygen atom represented by butyl ester is a quaternary carbon atom; methoxymethyl ester, ethoxymethyl ester, 1-ethoxyethyl ester, 1-isobutoxyethyl ester, 1-isopropoxyethyl Ester, 1-ethoxypropyl ester, 1- (2-methoxyethoxy) ethyl ester, 1- (2-acetoxyethoxy) ethyl ester, 1- [2- (1-adamantyloxy) ethoxy] ethyl ester, 1- [2 -(1-adamantanecarbonyloxy) ethoxy] ethyl ester Acetal-type esters such as tetrahydro-2-furyl ester and tetrahydro-2-pyranyl ester; isobornyl ester and 1-alkylcycloalkyl ester, 2-alkyl-2-adamantyl ester, 1- (1-adamantyl) -1- Examples thereof include alicyclic esters in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, such as an alkylalkyl ester.

  Examples of the group having a carboxylic acid ester include a group having a (meth) acrylic acid ester, a norbornene carboxylic acid ester, a tricyclodecene carboxylic acid ester, and a tetracyclodecene carboxylic acid ester.

The resin of the resin composition of the present invention can be produced by addition polymerization of a monomer having an acid labile group and an olefinic double bond.
Such monomers include bulky groups such as alicyclic structures such as 2-alkyl-2-adamantyl groups and 1- (1-adamantyl) -1-alkylalkyl groups as acid labile groups. Monomers are preferred because the resolution of the resulting resist tends to be excellent.
Specific examples of the monomer containing a bulky group include 2-alkyl-2-adamantyl (meth) acrylate, 1- (1-adamantyl) -1-alkylalkyl (meth) acrylate, and 5-norbornene-2. -2-alkyl-2-adamantyl carboxylate, 1- (1-adamantyl) -1-alkylalkyl 5-norbornene-2-carboxylate, 2-alkyl-2-adamantyl α-chloroacrylate, α-chloroacrylic acid 1- (1-adamantyl) -1-alkylalkyl and the like.

  In particular, when 2-alkyl-2-adamantyl (meth) acrylate or 2-alkyl-2-adamantyl α-chloroacrylate is used as a monomer, it is preferable because the resolution of the resulting resist tends to be excellent.

  Specifically, as 2-alkyl-2-adamantyl (meth) acrylate, for example, 2-methyl-2-adamantyl acrylate, 2-methyl-2-adamantyl methacrylate, 2-ethyl-2-acrylate Examples thereof include adamantyl, 2-ethyl-2-adamantyl methacrylate, 2-n-butyl-2-adamantyl acrylate, and the like. Examples of α-chloroacrylic acid 2-alkyl-2-adamantyl include α-chloroacrylic acid. Examples include 2-methyl-2-adamantyl and 2-ethyl-2-adamantyl α-chloroacrylate.

  Among these, when 2-ethyl-2-adamantyl (meth) acrylate or 2-isopropyl-2-adamantyl (meth) acrylate is used, the resulting resist tends to have excellent sensitivity and heat resistance. preferable.

  (Meth) acrylic acid 2-alkyl-2-adamantyl can be usually produced by a reaction of 2-alkyl-2-adamantanol or a metal salt thereof with acrylic acid halide or methacrylic acid halide.

  The resin used in the present invention may contain a structural unit derived from an acid-stable monomer in addition to a structural unit derived from a monomer having an acid-labile group. Here, the structure derived from an acid-stable monomer means a structure that is not cleaved by the salt (I) of the present invention.

  Specifically, a structural unit derived from a monomer having a free carboxylic acid group such as acrylic acid or methacrylic acid, or a structural unit derived from an aliphatic unsaturated dicarboxylic anhydride such as maleic anhydride or itaconic anhydride , A structural unit derived from 2-norbornene, a structural unit derived from (meth) acrylonitrile, a carbon atom adjacent to the oxygen atom is a secondary carbon atom or an alkyl ester or 1-adamantyl ester of a tertiary carbon atom (meth) Structural units derived from acrylates, structural units derived from styrene monomers such as p- or m-hydroxystyrene, derived from (meth) acryloyloxy-γ-butyrolactone in which the lactone ring may be substituted with an alkyl group And a structural unit. In the 1-adamantyl ester, the carbon atom adjacent to the oxygen atom is a quaternary carbon atom. However, the 1-adamantyl ester is an acid-stable group, and a hydroxyl group or the like may be bonded to the 1-adamantyl ester.

  Specific examples of acid-stable monomers include 3-hydroxy-1-adamantyl (meth) acrylate, 3,5-dihydroxy-1-adamantyl (meth) acrylate, α- (meth) acryloyloxy-γ-butyrolactone, β- (meth) acryloyloxy-γ-butyrolactone, monomer deriving the structural unit represented by formula (a), monomer deriving the structural unit represented by (b), olefinic double bond in the molecule such as hydroxystyrene, norbornene Examples thereof include alicyclic compounds having an aliphatic unsaturated dicarboxylic acid anhydride such as maleic anhydride, itaconic anhydride and the like.

  Among these, in particular, structural units derived from styrene monomers such as p- or m-hydroxystyrene, structural units derived from 3-hydroxy-1-adamantyl (meth) acrylate, (meth) acrylic acid 3,5 A resist obtained from a resin containing any one of a structural unit derived from -dihydroxy-1-adamantyl, a structural unit represented by formula (a), and a structural unit represented by formula (b) has an adhesive property to a substrate and This is preferable because the resolution of the resist tends to be improved.

（式中、Ｒ¹及びＲ²は、互いに独立に、水素原子又はメチル基を表し、Ｒ³及びＲ⁴は、互いに独立に水素原子、メチル基、トリフルオロメチル基又はハロゲン原子を表し、ｐ及びｑは、互いに独立に１〜３の整数を表す。ｐが２または３のときには、Ｒ³は互いに異なる基であってもよく、ｑが２または３のときには、Ｒ⁴は互いに異なる基であってもよい。）

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a methyl group; R ³ and R ⁴ each independently represent a hydrogen atom, a methyl group, a trifluoromethyl group, or a halogen atom; And q each independently represents an integer of 1 to 3. When p is 2 or 3, R ³ may be a different group, and when q is 2 or 3, R ⁴ is a different group. May be.)

  Monomers such as (meth) acrylic acid 3-hydroxy-1-adamantyl and (meth) acrylic acid 3,5-dihydroxy-1-adamantyl are commercially available. For example, the corresponding hydroxyadamantane is converted to (meth) acrylic acid or It can also be produced by reacting with the halide.

  In addition, a monomer such as (meth) acryloyloxy-γ-butyrolactone is obtained by reacting α- or β-bromo-γ-butyrolactone, in which the lactone ring may be substituted with an alkyl group, with acrylic acid or methacrylic acid, or lactone It can be produced by reacting an α- or β-hydroxy-γ-butyrolactone whose ring may be substituted with an alkyl group with an acrylic acid halide or a methacrylic acid halide.

  Specific examples of the monomer that gives the structural unit represented by formula (a) or formula (b) include (meth) acrylic acid esters of alicyclic lactones having a hydroxyl group such as the following, and mixtures thereof. It is done. These esters can be produced, for example, by reacting an alicyclic lactone having a corresponding hydroxyl group with (meth) acrylic acids (for example, JP-A No. 2000-26446).

  Here, as (meth) acryloyloxy-γ-butyrolactone, for example, α-acryloyloxy-γ-butyrolactone, α-methacryloyloxy-γ-butyrolactone, α-acryloyloxy-β, β-dimethyl-γ-butyrolactone, α- Methacryloyloxy-β, β-dimethyl-γ-butyrolactone, α-acryloyloxy-α-methyl-γ-butyrolactone, α-methacryloyloxy-α-methyl-γ-butyrolactone, β-acryloyloxy-γ-butyrolactone, β- Examples include methacryloyloxy-γ-butyrolactone, β-methacryloyloxy-α-methyl-γ-butyrolactone, and the like.

  In the case of KrF excimer laser exposure, sufficient transmittance can be obtained even if a structural unit derived from a styrene monomer such as p- or m-hydroxystyrene is used as the structural unit of the resin. Such a copolymer resin can be obtained by radically polymerizing the corresponding (meth) acrylic acid ester monomer, acetoxystyrene, and styrene and then deacetylating with an acid.

  Moreover, since the resin containing a structural unit derived from 2-norbornene has an alicyclic skeleton directly in the main chain, it has a sturdy structure and exhibits excellent dry etching resistance. The structural unit derived from 2-norbornene can be introduced into the main chain by radical polymerization using, in addition to the corresponding 2-norbornene, an aliphatic unsaturated dicarboxylic anhydride such as maleic anhydride or itaconic anhydride. Therefore, the one formed by opening the double bond of the norbornene structure can be represented by the formula (c), and the one formed by opening the double bond of maleic anhydride and itaconic anhydride is respectively It can represent with Formula (d) and Formula (e).

Here, R ⁵ and R ⁶ in formula (c) are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, a carboxyl group, a cyano group, or —COOU (U is an alcohol residue). Or R ⁵ and R ⁶ are bonded to each other to represent a carboxylic anhydride residue represented by —C (═O) OC (═O) —.
When R ⁵ and R ⁶ are a group —COOU, the carboxyl group is an ester group, and the alcohol residue corresponding to U has, for example, about 1 to 8 carbon atoms that may be substituted. And an alkyl group, a 2-oxooxolan-3- or -4-yl group. Here, in the alkyl group, a hydroxyl group, an alicyclic hydrocarbon residue, or the like may be bonded as a substituent.
Specific examples when R ⁵ and R ⁶ are alkyl groups include a methyl group, an ethyl group, and a propyl group. Specific examples of the alkyl group to which a hydroxyl group is bonded include a hydroxymethyl group and 2-hydroxyethyl group. Group and the like.

As described above, specific examples of the norbornene structure represented by the formula (c), which is a monomer that gives a stable structural unit to an acid, include the following compounds.
2-norbornene,
2-hydroxy-5-norbornene,
5-norbornene-2-carboxylic acid,
Methyl 5-norbornene-2-carboxylate,
2-hydroxy-1-ethyl 5-norbornene-2-carboxylate,
5-norbornene-2-methanol,
5-norbornene-2,3-dicarboxylic anhydride.

In addition, if U of R ⁵ and R ⁶ —COOU in the formula (c) is an acid labile group such as an alicyclic ester in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, Although it has a norbornene structure, it is a structural unit having an acid labile group. Examples of the monomer containing a norbornene structure and an acid labile group include, for example, 5-norbornene-2-carboxylic acid-t-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, and 5-norbornene. 2-carboxylate 1-methylcyclohexyl, 5-norbornene-2-carboxylic acid 2-methyl-2-adamantyl, 5-norbornene-2-carboxylic acid 2-ethyl-2-adamantyl, 5-norbornene-2-carboxylic acid 1- (4-methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- (4-Oxocyclohexyl) ethyl, 5-norbornene-2-carboxylic acid 1- (1-adama) Chill) -1-methylethyl and the like.

  The resin used in the resin composition of the present invention varies depending on the type of radiation used for patterning exposure and the type of acid labile group, but is usually derived from a monomer having an acid labile group in the resin. The content of the structural unit is adjusted to a range of 10 to 80 mol%.

  And as a structural unit derived from a monomer having an acid labile group, in particular, 2-alkyl-2-adamantyl (meth) acrylate and 1- (1-adamantyl) -1-alkylalkyl (meth) acrylate When the derived structural unit is included, if the structural unit is 15 mol% or more of the total structural units constituting the resin, the resin has a rugged structure because of the alicyclic group, and the resist has a dry etching resistance. Is advantageous.

  In addition, when using an alicyclic compound having an olefinic double bond in the molecule and an aliphatic unsaturated dicarboxylic acid anhydride as monomers, these tend to be difficult to undergo addition polymerization. These are preferably used in excess.

  Further, as the monomer used, monomers having the same olefinic double bond but different acid labile groups may be used in combination, or monomers having the same acid labile group but different olefinic double bonds may be used. You may use together, and you may use together the monomer from which the combination of an acid labile group and an olefinic double bond differs.

  When the resin composition of the present invention is used as a chemically amplified resist composition, a basic compound, preferably a basic nitrogen-containing organic compound, particularly preferably an amine or ammonium salt is contained. By adding a basic compound as a quencher, it is possible to improve the performance degradation due to the deactivation of the acid accompanying the holding after exposure. Specific examples of the basic compound used for the quencher include those represented by the following formulas.

In the formula, R ¹¹ , R ¹² and R ¹⁷ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has about 6 to 10 carbon atoms. Of carbon atoms. Further, at least one hydrogen atom on the alkyl group, cycloalkyl group or aryl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. Good. At least one hydrogen atom on the amino group may be independently substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹³ or R ¹⁴ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an alkoxy group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms. Alternatively, R ¹³ and R ¹⁴ may be bonded to form an aromatic ring.
Further, at least one hydrogen atom on the alkyl group, cycloalkyl group, aryl group, or alkoxy group is independently a hydroxyl group, an amino group, or an alkoxy group having about 1 to 6 carbon atoms. May be substituted. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁵ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group or a nitro group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms.
Further, at least one hydrogen atom on the alkyl group, cycloalkyl group, aryl group, or alkoxy group is independently a hydroxyl group, an amino group, or an alkoxy group having about 1 to 6 carbon atoms. May be substituted. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁶ represents an alkyl group or a cycloalkyl group. The alkyl group preferably has about 1 to 6 carbon atoms, and the cycloalkyl group preferably has about 5 to 10 carbon atoms. Furthermore, at least one hydrogen atom on the alkyl group or cycloalkyl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁷ , R ¹⁸ , R ¹⁹ and R ²⁰ each independently represents an alkyl group, a cycloalkyl group or an aryl group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. Has about carbon atoms. Furthermore, at least one hydrogen atom on the alkyl group, cycloalkyl group or aryl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. . At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

W represents an alkylene group, a carbonyl group, an imino group, a sulfide group or a disulfide group. The alkylene group preferably has about 2 to 6 carbon atoms.
Further, in R ^{11 to} R ²⁰ , any of those that can take both a linear structure and a branched structure may be used.

  Specific examples of such compounds include hexylamine, heptylamine, octylamine, nonylamine, decylamine, aniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, 1- or 2-naphthylamine, and ethylenediamine. , Tetramethylenediamine, hexamethylenediamine, 4,4′-diamino-1,2-diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′- Diethyldiphenylmethane, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, N-methylaniline, piperidine, diphenylamine, triethylamine, trimethylamine, tripropylamine, tributylamine , Tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine Methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, N, N-dimethylaniline, 2,6-isopropylaniline, imidazole, pyridine, -Methylpyridine, 4-methylimidazole, bipyridine, 2,2'-dipyridylamine, di-2-pyridyl ketone, 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,3-di (4-pyridyl) propane, 1,2-bis (2-pyridyl) ethylene, 1,2-bis (4-pyridyl) ethylene, 1,2-bis (4-pyridyloxy) ethane, 4 , 4′-dipyridyl sulfide, 4,4′-dipyridyl disulfide, 1,2-bis (4-pyridyl) ethylene, 2,2′-dipicolylamine, 3,3′-dipicolylamine, tetramethylammonium hydroxide Tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetra-n-hexylammonium hydroxide, tetra-n- Examples include octylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-trifluoromethylphenyltrimethylammonium hydroxide, (2-hydroxyethyl) trimethylammonium hydroxide (commonly known as choline).

  Furthermore, a hindered amine compound having a piperidine skeleton as disclosed in JP-A-11-52575 can be used as a quencher.

The resin composition of the present invention preferably contains about 80 to 99.9% by weight of the resin and about 0.1 to 20% by weight of the acid generator based on the total solid content.
Further, when a basic compound that is a quencher is used as the chemically amplified resist composition, it is preferably contained in a range of about 0.01 to 1% by weight based on the total solid content of the resist composition.
The resist composition can further contain small amounts of various additives such as sensitizers, dissolution inhibitors, other resins, surfactants, stabilizers, and dyes as necessary.

  The resist composition of the present invention is usually used as a resist solution composition in a state in which each of the above components is dissolved in a solvent, and is usually used in industrial processes such as spin coating on a substrate such as a silicon wafer. Applied according to The solvent used here may be any solvent that dissolves each component, has an appropriate drying rate, and gives a uniform and smooth coating film after the solvent evaporates, and is usually used industrially in this field. Solvents can be used.

  For example, glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate, glycol ethers such as propylene glycol monomethyl ether, esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate And ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone, and cyclic esters such as γ-butyrolactone. These solvents can be used alone or in combination of two or more.

  The resist film coated and dried on the substrate is subjected to an exposure process for patterning, followed by a heat treatment for promoting a deprotecting group reaction, and then developed with an alkali developer. The alkaline developer used here may be various alkaline aqueous solutions used in this field, but in general, an aqueous solution of tetramethylammonium hydroxide or (2-hydroxyethyl) trimethylammonium hydroxide (common name: choline). Is often used.

  EXAMPLES Next, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited at all by these Examples.

In Examples and Comparative Examples, “%” and “part” representing content or use amount are based on weight unless otherwise specified. Further, the weight average molecular weight is a value obtained by gel permeation chromatography (HLC-8120GPC type manufactured by Tosoh Corporation, column is TSKgel Multipore HXL-M3, solvent is tetrahydrofuran) using polystyrene as a standard product.
The structure of the compound is confirmed by NMR (JEOL GX-270 or EX-270), mass spectrometry (LC is Agilent 1100, MASS is Agilent LC / MSD or LC / MSD TOF)) did.

  Synthesis example of acid generator 1: Synthesis of dimethylphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (acid generator B1)

(1) To 200 parts of difluoro (fluorosulfonyl) acetic acid methyl ester and 300 parts of ion-exchanged water, 460 parts of a 30% aqueous sodium hydroxide solution was added dropwise in an ice bath. The mixture was refluxed at 100 ° C. for 2.5 hours, cooled, and neutralized with 175 parts of concentrated hydrochloric acid. The obtained solution was concentrated to obtain 328.19 parts of difluorosulfoacetic acid sodium salt (the content was 62.8% because the inorganic salt was not removed).
(2) 123.3 parts of difluorosulfoacetic acid sodium salt (content 62.8%), 65.7 parts of 1-adamantane methanol and 600 parts of dichloroethane were added, 75.1 parts of p-toluenesulfonic acid was added, and 12 hours Heated to reflux. Thereafter, the mixture was concentrated to distill off dichloroethane, 400 parts of tert-butyl methyl ether was added, filtered after repulping. After adding 400 parts of acetonitrile to the residue and stirring, filtration was repeated twice, and the filtrate was concentrated to obtain 99.5 parts of difluorosulfoacetic acid-1-adamantylmethyl ester sodium salt.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.51 (d, 6H); 1.62 (dd, 6H); 1.92 (s, 3H); 3.80 (s, 2H)

(3) Dissolve 5.0 parts of thioanisole in 15.0 parts of acetonitrile, add 8.35 parts of silver (I) perchlorate, and add 11.4 parts of acetonitrile of 5.71 parts of methyl iodide. And stirred for 24 hours. After the precipitated solid was removed by filtration, the filtrate was concentrated to remove acetonitrile. To the concentrated solution, 36.8 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 8.22 parts of dimethylphenylsulfonium perchlorate as white crystals.

¹ H-NMR (dimethylsulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 3.25 (s, 6H); 7.67-7.80 (m, 3H); 8.03-8 .08 (m, 2H)

(4) 5.98 parts of difluorosulfoacetic acid-1-adamantyl methyl ester sodium salt obtained in (2) above was charged, and 35.9 parts of chloroform was added. To this suspension solution, 4.23 parts of dimethylphenylsulfonium perchlorate obtained in (3) above and 12.7 parts of ion-exchanged water were added. After stirring for 4 hours, the mixture was separated, and the aqueous layer was extracted with 23.9 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. The concentrate was added with 31.8 parts of tert-butyl methyl ether, stirred and then filtered to obtain 5.38 parts of dimethylphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (B1) as a white solid.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.51 (d, 6H); 1.62 (dd, 6H); 1.92 (s, 3H); 3.26 (s, 6H); 3.80 (s, 2H); 7.68-7.80 (m, 3H); 8.03-8.06 (m, 2H)
MS (ESI (+) Spectrum): M + 139.0 (C ₈ H ₁₁ S ⁺ = 139.06)
MS (ESI (−) Spectrum): M− 323.0 (C ₁₃ H ₁₇ F ₂ O ₅ S ⁻ = 323.08)

  Synthesis example of acid generator 2: Synthesis of methyldiphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (acid generator B2)

(1) Dissolve 6.56 parts of diphenyl sulfide in 19.7 parts of acetonitrile, add 7.30 parts of silver (I) perchlorate, and add 10.0 parts of acetonitrile of 5.00 parts of methyl iodide. And stirred for 24 hours. The precipitated solid was removed by filtration and then concentrated to distill off acetonitrile. To the concentrated liquid, 39.2 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 9.38 parts of methyldiphenylsulfonium perchlorate as white crystals.

¹ H-NMR (dimethylsulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 3.81 (s, 3H); 7.67-7.79 (m, 6H); 8.01-8 .04 (m, 4H)

(2) Acid generator synthesis example of acid generator B1 (Acid generator synthesis example 1) 8.29 parts of difluorosulfoacetate-1-adamantyl methyl ester sodium salt obtained by the same synthesis method as (2) 49.7 parts of chloroform was added. To this suspension solution, 9.38 parts of methyldiphenylsulfonium perchlorate obtained in (1) and 28.14 parts of ion-exchanged water were added. After stirring for 15 hours, the mixture was separated, and the aqueous layer was extracted with 33.1 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. The concentrated liquid was added with 33.8 parts of tert-butyl methyl ether, stirred and then decanted to obtain 7.81 parts of methyldiphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (B2) as a colorless liquid.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.50 (d, 6H); 1.61 (dd, 6H); 1.91 (s, 3H); 3.80 (s, 2H) 3.82 (s, 3H); 7.67-7.79 (m, 6H); 8.02-8.05 (m, 4H)
MS (ESI (+) Spectrum): M + 201.0 (C ₁₃ H ₁₃ S ⁺ = 201.07)
MS (ESI (−) Spectrum): M− 323.0 (C ₁₃ H ₁₇ F ₂ O ₅ S ⁻ = 323.08)

  Synthesis example of acid generator 3: Synthesis of n-butyldiphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (acid generator B3)

(1) 26.5 parts of diphenyl sulfide are dissolved in 79.4 parts of acetonitrile, 29.5 parts of silver (I) perchlorate is added, and 22.3 parts of acetonitrile is 22.3 parts of n-butyl iodide. Was added and stirred for 24 hours. After the precipitated solid was removed by filtration, the filtrate was concentrated to remove acetonitrile. To the concentrated solution, 135.9 parts of tert-butyl methyl ether was added and stirred, followed by filtration. Further, 101.7 parts of tert-butyl methyl ether was added to the residue, followed by filtration, followed by filtration to obtain 14.8 parts of n-butyldiphenylsulfonium perchlorate as white crystals.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 0.88 (t, 3H); 1.41-1.49 (m, 2H); 1.52-1 .64 (m, 2H); 4.31 (t, 2H); 7.69-7.82 (m, 6H); 8.08 (d, 4H)

(2) Acid generator synthesis example of acid generator B1 (acid generator synthesis example 1) 5.00 parts of difluorosulfoacetic acid-1-adamantyl methyl ester sodium salt obtained by the same synthesis method as (2) was charged. Then, 50.0 parts of chloroform was added. To this suspension solution, 13.94 parts of n-butyldiphenylsulfonium perchlorate obtained in (1) above and 41.82 parts of ion-exchanged water were added. After stirring for 15 hours, the mixture was separated, and the aqueous layer was extracted with 10.0 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. The concentrated solution was added with 37.6 parts of tert-butyl methyl ether, stirred and filtered. Further, 16.8 parts of ethyl acetate was added to the residue and stirred, followed by filtration to obtain 2.89 parts of n-butyldiphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (B3) as white crystals.

¹ H-NMR (dimethylsulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 0.88 (t, 3H); 1.42-1.67 (m, 16H); 1.91 (s , 3H); 3.80 (s, 2H); 4.33 (t, 2H); 7.71-7.83 (m, 6H); 8.09 (d, 4H)
MS (ESI (+) Spectrum): M + 243.11 (C ₁₆ H ₁₉ S ⁺ = 243.12)
MS (ESI (−) Spectrum): M−323.10 (C ₁₃ H ₁₇ F ₂ O ₅ S ⁻ = 323.08)

  Acid generator synthesis example 4: Synthesis of methyldibenzylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (acid generator B4)

(1) Dissolve 5.0 parts of benzyl sulfide in 15.0 parts of acetonitrile, add 4.84 parts of silver (I) perchlorate, and add 6.6 parts of a solution of 3.31 parts of methyl iodide in acetonitrile. And stirred for 24 hours. After the precipitated solid was removed by filtration, the filtrate was concentrated to remove acetonitrile. To the concentrated solution, 25.9 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 5.89 parts of methyldibenzylsulfonium perchlorate as white crystals.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 2.67 (s, 3H); 4.59 (d, 2H); 4.77 (d, 2H); 7.45 (s, 10H)

(2) Acid generator synthesis example of acid generator B1 (acid generator synthesis example 1) 3.11 parts of difluorosulfoacetic acid-1-adamantyl methyl ester sodium salt obtained by the same synthesis method as (2) 31.1 parts of chloroform was added. To this suspension solution, 3.18 parts of methyldibenzylsulfonium perchlorate obtained in (1) above and 9.54 parts of ion-exchanged water were added. After stirring for 4 hours, the mixture was separated, and the aqueous layer was extracted with 15.5 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. To the concentrated liquid, 19.4 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 3.65 parts of methyldibenzylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (B4) as white crystals.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.50 (d, 6H); 1.62 (dd, 6H); 1.92 (s, 3H); 2.67 (s, 3H); 3.80 (s, 2H); 4.59 (d, 2H); 4.77 (d, 2H); 7.45 (s, 10H)
MS (ESI (+) Spectrum): M + 229.2 (C ₁₅ H ₁₇ S ⁺ = 229.10)
MS (ESI (−) Spectrum): M− 323.0 (C ₁₃ H ₁₇ F ₂ O ₅ S ⁻ = 323.08)

  Acid generator synthesis example 5: Synthesis of methyldiphenylsulfonium 4-oxo-1-adamantyloxycarbonyldifluoromethanesulfonate (acid generator B5)

(1) Acid generator synthesis example of acid generator B1 (acid generator synthesis example 1) 5.0 parts of sodium salt of difluorosulfoacetate obtained by the same synthesis method as (1) (content 62.8%) Then, 2.6 parts of 4-oxo-1-adamantanol and 100 parts of ethylbenzene were added, 0.8 part of concentrated sulfuric acid was added, and the mixture was heated to reflux for 30 hours. After cooling, the mixture was filtered and the residue was washed with tert-butyl methyl ether to obtain 5.5 parts of difluorosulfoacetic acid-4-oxo-1-adamantyl ester sodium salt. As a result of analysis by ¹ H-NMR, since the inorganic salt was not removed, the content was 49.1%.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.84 (d, 2H); 2.00 (d, 2H); 2.29-2.32 (m , 7H); 2.54 (s, 2H)

(2) Difluorosulfoacetic acid-4-oxo-1-adamantyl ester sodium salt (5.0 parts, content: 49.1%) was added and chloroform (50.0 parts) was added. To this suspension, 42.0 parts (concentration 5.0%) of an aqueous methyldiphenylsulfonium chloride solution was added. After stirring for 15 hours, the mixture was separated, and the aqueous layer was extracted with 25.0 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. The concentrated solution was decanted after adding 29.6 parts of tert-butyl methyl ether and stirring. 16.6 parts of ethyl acetate was added to the residue and stirred, followed by decantation to obtain 1.6 parts of methyldiphenylsulfonium 4-oxo-1-adamantyloxycarbonyldifluoromethanesulfonate (B5) as a pale yellow liquid.

¹ H-NMR (dimethylsulfoxide-d ₆ ): δ (ppm) 1.82 (d, 2H); 1.99 (d, 2H); 2.21-2.35 (m, 7H); 2.52 (S, 2H); 3.81 (s, 3H); 7.67-7.79 (m, 6H); 8.01-8.06 (m, 4H)

  Acid generator synthesis example 6: methyldiphenylsulfonium 1- (hexahydro-2-oxo-3,5-methano-2H-cyclopenta [b] furan-6-yloxycarbonyl) difluoromethanesulfonate (acid generator B6) Composition

(1) Acid generator synthesis example of acid generator B1 (acid generator synthesis example 1) 30.0 parts of difluorosulfoacetate sodium salt obtained by the same synthesis method as (1) (content 62.8%) , 14.7 parts of hexahydro-6-hydroxy-3,5-methano-2H-cyclopenta [b] furan-2-one, 300 parts of toluene, and 18.1 parts of p-toluenesulfonic acid (p-TsOH) In addition, the mixture was heated to reflux for 12 hours. Thereafter, after filtration, 100 parts of acetonitrile was added to the residue, followed by stirring, and the filtrate was concentrated to obtain difluorosulfoacetate hexahydro-2-oxo-3,5-methano-2H-cyclopenta [b] furan-6-yl ester. 26.7 parts of sodium salt were obtained.

¹ H-NMR (dimethylsulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.57-1.67 (m, 2H); 1.91-2.06 (m, 2H); 2 .53 (dd, 1H); 3.21 (td, 1H); 4.51 (d, 1H); 4.62 (s, 1H)

(2) Difluorosulfoacetate hexahydro-2-oxo-3,5-methano-2H-cyclopenta [b] furan-6-yl ester 2.5 parts of sodium salt was added and 50.0 parts of chloroform was added. To this suspension, 43.5 parts (concentration 5.0%) of an aqueous methyldiphenylsulfonium chloride solution was added. After stirring for 15 hours, the mixture was separated, and the aqueous layer was extracted with 25.0 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. The concentrated solution was decanted after 24.2 parts of tert-butyl methyl ether was added and stirred. By adding 11.9 parts of ethyl acetate to the residue and stirring, decantation was performed to obtain 1.1 parts of methyldiphenylsulfonium 4-oxo-1-adamantyloxycarbonyldifluoromethanesulfonate (B5) as a pale yellow liquid.

¹ H-NMR (dimethyl sulfoxide-d ₆ ): δ (ppm) 1.55-1.66 (m, 2H); 1.89-2.07 (m, 2H); 2.52 (dd, 1H) 3.21 (td, 1H); 3.81 (s, 3H); 4.49 (d, 1H); 4.61 (s, 1H); 7.67-7.79 (m, 6H); 8.01-8.05 (m, 4H)

Synthesis Example 1 of Comparative Control Acid Generator 1: Synthesis of triphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (acid generator C1) (1) Obtained by the same synthesis method as (2) of acid generator synthesis example 3 39.4 parts of difluorosulfoacetic acid sodium salt (content 63.5%), 21.0 parts of 1-adamantane methanol and 200 parts of dichloroethane were charged, and 24.0 parts of p-toluenesulfonic acid (p-TsOH) was added. In addition, the mixture was heated to reflux for 7 hours. Thereafter, the mixture was concentrated to distill off dichloroethane, 250 parts of tert-butyl methyl ether was added to the concentrated residue, repulped and filtered. To the residue, 250 parts of acetonitrile was added and stirred, followed by filtration. The filtrate was concentrated to obtain 32.8 parts of difluorosulfoacetic acid-1-adamantylmethyl ester sodium salt.

(2) 32.8 parts of difluorosulfoacetic acid-1-adamantylmethyl ester sodium salt obtained in (1) above was charged and dissolved in 100 parts of ion-exchanged water. To this solution, 28.3 parts of triphenylsulfonium chloride and 140 parts of methanol were added. After stirring for 15 hours, the mixture was concentrated and extracted twice with 200 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. The white precipitate obtained after adding 300 parts of tert-butyl methyl ether to the concentrated liquid and stirring was filtered and dried under reduced pressure to obtain 39.7 of triphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (C1) as white crystals. I got a part.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.52 (d, 6H); 1.63 (dd, 6H); 1.93 (s, 3H); 3.81 (s, 2H); 7.76-7.90 (m, 15H)
MS (ESI (+) Spectrum): M + 263.2 (C ₁₈ H ₁₅ S ⁺ = 263.09)
MS (ESI (−) Spectrum): M− 323.0 (C ₁₃ H ₁₇ F ₂ O ₅ S ⁻ = 323.08)

  Synthesis Example 2 of Comparative Acid Generator: Synthesis of Triphenylsulfonium 4-oxo-1-adamantyloxycarbonyldifluoromethanesulfonate (Acid Generator C2)

Acid generator B5 acid generator synthesis example (acid generator synthesis example 5) 5.4 parts of difluorosulfoacetic acid-4-oxo-1-adamantyl ester sodium salt obtained by the same synthesis method as (1) 35.6%), and a mixed solvent of 16 parts acetonitrile and 16 parts ion-exchanged water was added. To this was added a solution of 1.7 parts triphenylsulfonium chloride, 5 parts acetonitrile, and 5 parts ion-exchanged water. After stirring for 15 hours, the mixture was concentrated and extracted with 142 parts of chloroform. The organic layer was washed repeatedly with ion-exchanged water until neutral, and the obtained organic layer was concentrated. To the concentrated liquid, 24 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 1.7 parts of triphenylsulfonium 4-oxo-1-adamantyloxycarbonyldifluoromethanesulfonate (C2) as a white solid.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.83 (d, 2H, J = 12.7 Hz); 2.00 (d, 2H, J = 12. 0Hz); 2.29-2.32 (m, 7H); 2.53 (s, 2H); 7.75-7.91 (m, 15H)
MS (ESI (+) Spectrum): M + 263.2 (C ₁₈ H ₁₅ S ⁺ = 263.09)
MS (ESI (−) Spectrum): M− 323.0 (C ₁₂ H ₁₃ F ₂ O ₆ S ⁻ = 323.04)
Synthesis Example 3 of Comparative Acid Generator: Synthesis of Triphenylsulfonium 1-adamantylmethoxycarbonyldifluoromethanesulfonate (Acid Generator C3)

Acid Generator B6 Acid Generator Synthesis Example (Acid Generator Synthesis Example 6) Difluorosulfoacetate hexahydro-2-oxo-3,5-methano-2H-cyclopenta [b] obtained by the same synthesis method as (1) ] 26.7 parts of furan-6-yl ester sodium salt were charged and dissolved in 267 parts of acetonitrile. To this solution, 23.9 parts of triphenylsulfonium chloride and 239 parts of ion-exchanged water were added. After stirring for 15 hours, the mixture was concentrated and extracted twice with 200 parts of chloroform. The organic layers were combined and washed repeatedly with ion-exchanged water until neutral, and the resulting organic layer was concentrated. To the concentrate, 200 parts of tert-butyl methyl ether was added and stirred, followed by filtration to give triphenylsulfonium 1- (hexahydro-2-oxo-3,5-methano-2H-cyclopenta [b] furan- 67.7 parts of 6-yloxycarbonyl) difluoromethanesulfonate (C3) were obtained.

¹ H-NMR (dimethylsulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.57-1.67 (m, 2H); 1.91-2.06 (m, 2H); 2 .53 (dd, 1H); 3.21 (td, 1H); 4.51 (d, 1H); 4.62 (s, 1H); 7.91-7.76 (m, 15H)
MS (ESI (+) Spectrum): M + 263.2 (C ₁₈ H ₁₅ S ⁺ = 263.09)
MS (ESI (−) Spectrum): M− 311.0 (C ₁₀ H ₉ F ₂ O ₇ S ⁻ = 311.00)

Resin Synthesis Example 1: Synthesis of Resin A1 2-ethyl-2-adamantyl methacrylate, 3-hydroxy-1-adamantyl methacrylate, and α-methacryloyloxy-γ-butyrolactone were mixed with 5: 2.5: 2.5. The methyl isobutyl ketone was added 2 times by weight with respect to the total monomer to prepare a solution. Thereto, 2 mol% of azobisisobutyronitrile as an initiator was added with respect to the total amount of monomers and heated at 80 ° C. for about 8 hours. Thereafter, the operation of pouring the reaction solution into a large amount of heptane and precipitating was performed three times for purification. As a result, a copolymer having a weight average molecular weight of about 9,200 was obtained. This copolymer has each structural unit shown by following Formula, and this is set as resin A1.

  Next, in addition to the resin (A1) obtained in the above resin synthesis example, a resist composition was prepared and evaluated using the raw materials shown below.

酸発生剤Ｂ３：

酸発生剤Ｂ５：

酸発生剤Ｂ６：

酸発生剤Ｃ１：

酸発生剤Ｃ２：

酸発生剤Ｃ３：

＜クエンチャー＞
クエンチャーＱ１：２，６−ジイソプロピルアニリン
＜溶剤＞
溶剤Ｙ１：
プロピレングリコールモノメチルエーテルアセテート ５１．５部
２−ヘプタノン ３５．０部
γ−ブチロラクトン ３．５部 <Acid generator>
Acid generator B2:

Acid generator B3:

Acid generator B5:

Acid generator B6:

Acid generator C1:

Acid generator C2:

Acid generator C3:

<Quencher>
Quencher Q1: 2,6-diisopropylaniline <solvent>
Solvent Y1:
Propylene glycol monomethyl ether acetate 51.5 parts 2-heptanone 35.0 parts γ-butyrolactone 3.5 parts

Examples 1-4 and Comparative Examples 1-3
The following components were mixed and dissolved, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution.

Resin (type and amount are listed in Table 1)
Acid generator (type and amount are listed in Table 1)
Quencher (type and amount are listed in Table 1)
Solvent (type is listed in Table 1)

  An organic antireflective film having a thickness of 780 mm is formed by applying “ARC-29A-8”, an organic antireflective film composition manufactured by Nissan Chemical Industries, on a silicon wafer and baking it at 215 ° C. for 60 seconds. Next, the resist solution was spin-coated thereon so that the film thickness after drying was 0.25 μm. After application of the resist solution, pre-baking was performed for 60 seconds on the direct hot plate at the temperature shown in the column “PB” in Tables 1 and 3. In Table 1, ArF excimer stepper ("NSR ArF" manufactured by Nikon Co., Ltd., NA = 0.55, 2/3 Annular) is used in Table 1, and in Table 3, ArF excimer stepper is used. [The line and space pattern was exposed by changing the exposure stepwise using “FPA5000-AS3” manufactured by Canon Inc., NA = 0.75 2/3 Annular].

  After exposure, post-exposure baking is performed for 60 seconds on the hot plate at the temperature indicated in the column of “PEB” in Tables 1 and 3, and then paddles are added for 60 seconds with a 2.38 wt% tetramethylammonium hydroxide aqueous solution. Developed.

  Under the conditions in Table 1, the bright field pattern after development on the organic antireflection film substrate was observed with a scanning electron microscope, and the results are shown in Table 2. The bright field pattern referred to here is obtained by exposure and development through a reticle in which a chrome layer (light-shielding layer) is formed in a line shape on the outside with a glass portion (translucent portion) as a base. After that, the resist layer around the line and space pattern is removed.

  Under the conditions of Table 3, the dark field pattern after development on the organic antireflection film substrate was observed with a scanning electron microscope. The results are shown in Table 4. The dark field pattern referred to here is obtained by exposure and development through a reticle having a glass surface (translucent portion) formed in a line form on the outside with a chromium layer (light-shielding layer) as a base, and thus exposure development. The rest is a pattern in which the resist layer around the line and space pattern is left.

  Resolution: Displayed with the minimum dimension of the line and space pattern separated by the exposure amount of effective sensitivity. The effective sensitivity in Table 2 is expressed by an exposure amount at which a 0.13 μm line and space pattern is 1: 1, and the effective sensitivity in Table 4 is 1: 1 for a 0.10 μm line and space pattern. It displayed with the exposure amount which becomes.

[Table 1]
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example No. Resin Acid generator Quencher Solvent PB / PEB
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example 1 A1 / 10 part B2 / 0.23 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
Example 2 A1 / 10 part B3 / 0.25 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
──────────────────────────────────────
Comparative Example 1 A1 / 10 part C1 / 0.26 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

[Table 2]
━━━━━━━━━━━━━━━━━━━━
Example No. Effective sensitivity Resolution
(mJ / cm ² ) (μm)
━━━━━━━━━━━━━━━━━━━━
Example 1 36.0 0.12
Example 2 24.0 0.12
────────────────────
Comparative Example 1 39.0 0.12
━━━━━━━━━━━━━━━━━━━━

[Table 3]
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example No. Resin Acid generator Quencher Solvent PB / PEB
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example 3 A1 / 10 part B5 / 0.23 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
Example 4 A1 / 10 part B6 / 0.23 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
──────────────────────────────────────
Comparative Example 2 A1 / 10 part C2 / 0.26 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
Comparative Example 3 A1 / 10 part C3 / 0.25 part Q1 / 0.0325 part Y1 130 ° C / 120 ° C
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

[Table 4]
━━━━━━━━━━━━━━━━━━━━
Example No. Effective sensitivity Resolution
(mJ / cm ² ) (μm)
━━━━━━━━━━━━━━━━━━━━
Example 3 36.0 0.09
Example 4 35.0 0.09
────────────────────
Comparative Example 2 37.0 0.09
Comparative Example 3 42.0 0.09
━━━━━━━━━━━━━━━━━━━━

According to Examples 1 and 2, the same resolution of 0.12 μm as in the comparative example was obtained, and the sensitivity was further improved.
In addition, according to Examples 3 to 4, the same resolution of 0.09 μm as in the comparative example was obtained, and the sensitivity was further improved.

  The salt of the present invention is suitably used as an acid generator for a chemically amplified positive resist composition that gives excellent resolution and sensitivity, and is particularly suitable for excimer laser lithography such as ArF and KrF and ArF immersion exposure lithography. It can be used as an acid generator for a chemically amplified positive resist composition.

Claims (5)

A salt represented by formula (IVa) to formula (IVd) , formula (IVe) to formula (IVh), formula (IVi) to formula (IVl), formula (IVm) or formula (IVVn) .

(In the formula (IVa) ~ formula (IVd), independently P ⁴ to P ⁶ are each, P ⁷ to P ⁹ in. Formula representing the straight-chain or branched alkyl group having 1 to 20 carbon atoms, represents an alkyl group having a carbon number of 1~12, h, g, f each represent an integer of 0 to 5.)

(In the formula (IVe) to the formula (IVh), P ^{4 to} P ⁶ each independently represents a linear or branched alkyl group having 1 to 20 carbon atoms. In the formula, P ^{7 to} P ⁹ are Represents an alkyl group having 1 to 12 carbon atoms, and h, g, and f each represents an integer of 0 to 5.)

(In the formula (IVi) to the formula (IVl), P ^{4 to} P ⁶ each independently represent a linear or branched alkyl group having 1 to 20 carbon atoms. In the formula, P ^{7 to} P ⁹ are Represents an alkyl group having 1 to 12 carbon atoms, and h, g, and f each represents an integer of 0 to 5.)

(In the formula (IVm) and the formula (IVn), P ^{4 to} P ⁶ each independently represents a linear or branched alkyl group having 1 to 20 carbon atoms. In the formula, P ^{7 to} P ⁹ are Represents an alkyl group having 1 to 12 carbon atoms, and h, g, and f each represents an integer of 0 to 5.) An acid generator comprising the salt according to claim 1 as an active ingredient. A resin composition comprising the acid generator according to claim 2 and a resin, wherein the resin has an acid labile group and is a resin insoluble or hardly soluble in an alkaline aqueous solution and acts with an acid. A resin composition, wherein the resin is a resin that can be dissolved in an alkaline aqueous solution. The resin composition according to claim 3 , wherein the resin is a resin containing a structural unit derived from a monomer having a bulky group and an acid-labile group. A chemically amplified resist composition comprising the resin composition according to claim 3 or 4 and a basic compound.