JP5358005B2 - Positive photosensitive acrylic resin and positive photosensitive resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin to offer a positive photosensitive resin composition which can form a rectangular profile or a profile in a rectangle-like shape after baking a formed pattern. <P>SOLUTION: A positive photosensitive acrylic resin is used that contains a carboxyl group in its main chain terminal and contains a repeating unit having a cyclic ether group with a 3-membered ring and/or a 4-membered ring, and is insoluble or hardly soluble with an alkali developer but is soluble with the alkali developer under the action of acid. <P>COPYRIGHT: (C)2013,JPO&amp;INPIT

Description

  The present invention relates to a positive photosensitive acrylic resin and a positive photosensitive resin composition using the same. Furthermore, it is related with the cured film manufactured using the positive photosensitive resin composition, and its manufacturing method. The present invention also relates to a pattern forming method using a positive photosensitive resin composition, a MEMS structure manufacturing method, a dry etching method, and a wet etching method. Furthermore, it is related with the manufacturing method of positive photosensitive acrylic resin.

Photosensitive resin compositions are used in manufacturing processes for display devices such as liquid crystal display devices and organic EL display devices, interlayer insulating films, semiconductor devices, MEMS (Micro Electro Mechanical Systems), and the like. In particular, chemically amplified positive resists are actively used because of their high resolution and high sensitivity.
As conventional photosensitive resin compositions, for example, Patent Document 1 discloses a positive photosensitive resin composition for etching resist, and Patent Document 2 discloses a positive photosensitive resin composition for etching resist. 3 shows an example of manufacturing a MEMS structure using a sacrificial layer resist, a resin composition for a positive interlayer insulating film material for use as a microlens forming agent in Patent Document 4, and Patent Documents 5 to 7 include a binder polymer. A photosensitive resin composition characterized by a main chain terminal is disclosed.

Japanese Patent Laid-Open No. 10-73923 Japanese Patent Laid-Open No. 10-026829 Special table 2008-533510 gazette JP 2004-264623 A JP 2009-104040 A JP 2010-11803 A JP 2005-122035 A

For example, in the case of a sacrificial layer resist at the time of producing a MEMS, the resist shape is reflected in the upper laminated structure as it is, and therefore, resist shape control is important.
In addition, when used as an etching resist in a dry etching process, a profile that is close to a rectangle and has a large taper angle is required in order to realize precise patterning by etching.
Furthermore, durability such as a certain degree of solvent resistance, chemical resistance and mechanical strength is required so that the resist film does not swell and peel off or dissolve and disappear in a dry etching or wet etching process.
When used as a thick film resist, high sensitivity is required in order to obtain an appropriate pattern in the development process, and the influence of heat flow and cure shrinkage increases in the thick film. It becomes even more important. The thick film is exemplified by a usage pattern of a resist having a dry film thickness of 4 to 100 μm after removing the solvent.

With a conventional etching resist, it has been difficult to obtain a rectangular shape or a profile close to a rectangular shape when a baking process for improving the strength of the cured film is performed.
For example, the photosensitive resin composition described in Patent Document 1 has a problem that a rectangular profile cannot be obtained due to heat flow during baking.
On the other hand, in Patent Document 4, the evaluation is better as the curve of the pattern and the taper is better, and the evaluation is worse as the taper shape is rectangular.
The problem to be solved by the present invention is to provide a positive photosensitive resin composition capable of forming a rectangle or a profile close to a rectangle even after the formed pattern is baked.
Further, Patent Documents 5 to 7 disclose positive photosensitive resin compositions using a polymer in which an interaction group is introduced at the end of the main chain. However, the inventors of the present application have examined rectangularity and taper angle. I found that there was a problem.

  The present invention aims to solve the above-mentioned problems, and provides a positive photosensitive resin composition capable of forming a rectangular shape or a profile close to a rectangular shape even after the formed pattern is baked. It is an object of the present invention to provide a positive photosensitive acrylic resin that can be used.

As a result of investigation by the inventors of the present invention under the above problems, the polymer (binder) component of the photosensitive resin composition has a repeating unit having a 3-membered ring or a 4-membered cyclic ether group, and By using a polymer having a carboxyl group at the end of the main chain, it is possible to provide a positive photosensitive resin composition capable of forming a rectangle or a profile close to a rectangle even after the formed pattern is baked. I found out.
The reason why such a copolymer makes it possible to form a rectangular or near-rectangular profile even after the formed pattern is baked is that the carboxyl group at the end of the polymer main chain is baked to form a 3-membered or 4-membered ring. It is considered that the polymer is regularly arranged and crosslinked rather than simply having a carboxyl group in the polymer side chain.

（一般式（１）中、Ｒ¹は水素原子またはアルキル基を表し、Ｌは２価の連結基を表し、Ｒ²〜Ｒ⁴は、それぞれ、水素原子、アルキル基、またはフェニル基を表す。ｎは１または２を表す。Ｒ²、Ｒ³またはＲ⁴が、Ｌが有する置換基と結合して環を形成してもよい。）
＜３＞前記アクリル樹脂の重量平均分子量が５０００以上である、＜１＞または＜２＞に記載のポジ型感光性樹脂組成物。
＜４＞前記アクリル樹脂が、上記３員環および／または４員環の環状エーテル基を有する繰り返し単位に加えて、さらに、カルボキシ基またはフェノール性水酸基が酸分解性基で保護された残基を有する繰り返し単位を有する、＜１＞〜＜３＞のいずれか１項に記載のポジ型感光性樹脂組成物。
＜５＞さらに、光酸発生剤を含有する、＜１＞〜＜４＞のいずれか１項に記載のポジ型感光性樹脂組成物。
＜６＞光酸発生基が、オニウム塩、および／または、オキシムスルホネ―トである、＜５＞に記載のポジ型感光性樹脂組成物。
＜７＞架橋剤をさらに含む、＜１＞〜＜６＞のいずれか１項に記載のポジ型感光性樹脂組成物。
＜８＞溶剤をさらに含む、＜１＞〜＜７＞のいずれか１項に記載のポジ型感光性樹脂組成物。
＜９＞＜１＞〜＜８＞のいずれか１項に記載のポジ型感光性樹脂組成物を、光および熱の少なくとも一方を付与して硬化させた硬化膜。
＜１０＞層間絶縁膜である、＜９＞に記載の硬化膜。
＜１１＞（１）＜１＞〜＜８＞のいずれか１項に記載のポジ型感光性樹脂組成物を基板上に塗布する工程、
（２）塗布されたポジ型感光性樹脂組成物から溶剤を除去する工程、
（３）溶剤を除去されたポジ型感光性樹脂組成物を活性放射線で露光する工程、
（４）露光されたポジ型感光性樹脂組成物を水性現像液で現像する工程、および、
（５）現像されたポジ型感光性樹脂組成物を熱硬化するポストベーク工程、
を含む硬化膜の形成方法。
＜１２＞前記露光工程における露光後に、加熱処理を行わずに前記現像工程を行う、＜１１＞に記載の硬化膜の形成方法。
＜１３＞エッチングレジスト用である、＜１＞〜＜８＞のいずれか１項に記載のポジ型感光性樹脂組成物。
＜１４＞ＭＥＭＳ用構造部材用である、＜１＞〜＜８＞のいずれか１項に記載のポジ型感光性樹脂組成物。
＜１５＞＜１＞〜＜８＞のいずれか１項に記載のポジ型感光性樹脂組成物から溶剤を除去し膜を形成する膜形成工程、
前記膜を活性光線によりパターン状に露光する露光工程、
露光された前記膜を水性現像液により現像しパターンを形成する現像工程、および、
前記パターンを加熱するベーク工程、
を含むパターン形成方法。
＜１６＞前記現像工程後、かつ前記ベーク工程の前に、前記パターンを活性光線により露光するポスト露光工程を含む、＜１５＞に記載のパターン形成方法。
＜１７＞＜１５＞または＜１６＞に記載のパターン形成方法により作製したパターンを構造体積層時の犠牲層として用いて構造体を作製する工程、および、
前記犠牲層をプラズマ処理にて除去する工程、を含むＭＥＭＳ構造体の製造方法。
＜１８＞＜１５＞または＜１６＞に記載のパターン形成方法により作製したパターンをドライエッチング用レジストとして用いてドライエッチングを行う工程、および、
前記パターンをプラズマ処理または薬品処理により除去する工程、
を含むドライエッチング方法。
＜１９＞＜１５＞または＜１６＞に記載のパターン形成方法により作製したパターンをウェットエッチング用レジストとして用いてウェットエッチングを行う工程、および、
前記パターンをプラズマ処理または薬品処理により除去する工程、
を含むウェットエッチング方法。
＜２０＞重合性モノマーの重合時にカルボキシル基を有する連鎖移動剤を用いるか、カルボキシル基を有する重合開始剤を用いることによって、アクリル樹脂を製造することを含む、＜１＞〜＜８＞のいずれか１項に記載のポジ型感光性樹脂組成物の製造方法。 Specifically, the above problem has been solved by the following means <1>, preferably <2> to <21>.
<1> Containing a carboxyl group at the end of the main chain and containing a repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group, it is insoluble or hardly soluble in an alkali developer and alkalinized by the action of an acid A positive photosensitive resin composition comprising an acrylic resin that is soluble in a developer.
<2> The positive photosensitive resin composition according to <1>, wherein the acrylic resin has a repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group represented by the general formula (1). .
General formula (1)

(In General Formula (1), R ¹ represents a hydrogen atom or an alkyl group, L represents a divalent linking group, and R ^{2 to} R ⁴ each represents a hydrogen atom, an alkyl group, or a phenyl group. n represents 1 or 2. R ² , R ^3, or R ⁴ may combine with a substituent of L to form a ring.
<3> The positive photosensitive resin composition according to <1> or <2>, wherein the acrylic resin has a weight average molecular weight of 5000 or more.
<4> In addition to the repeating unit having the 3-membered ring and / or 4-membered cyclic ether group, the acrylic resin further includes a residue in which a carboxy group or a phenolic hydroxyl group is protected with an acid-decomposable group. The positive photosensitive resin composition according to any one of <1> to <3>, having a repeating unit.
<5> The positive photosensitive resin composition according to any one of <1> to <4>, further containing a photoacid generator.
<6> The positive photosensitive resin composition according to <5>, wherein the photoacid-generating group is an onium salt and / or an oxime sulfonate.
<7> The positive photosensitive resin composition according to any one of <1> to <6>, further including a crosslinking agent.
<8> The positive photosensitive resin composition according to any one of <1> to <7>, further including a solvent.
<9> A cured film obtained by curing the positive photosensitive resin composition according to any one of <1> to <8> by applying at least one of light and heat.
<10> The cured film according to <9>, which is an interlayer insulating film.
<11> (1) The process of apply | coating the positive photosensitive resin composition of any one of <1>-<8> on a board | substrate,
(2) a step of removing the solvent from the applied positive photosensitive resin composition;
(3) a step of exposing the positive photosensitive resin composition from which the solvent has been removed with actinic radiation,
(4) a step of developing the exposed positive photosensitive resin composition with an aqueous developer, and
(5) a post-baking step of thermosetting the developed positive photosensitive resin composition;
A method for forming a cured film comprising:
<12> The method for forming a cured film according to <11>, wherein the development step is performed without performing a heat treatment after the exposure in the exposure step.
<13> The positive photosensitive resin composition according to any one of <1> to <8>, which is used for an etching resist.
<14> The positive photosensitive resin composition according to any one of <1> to <8>, which is for a structural member for MEMS.
<15> A film forming step of forming a film by removing the solvent from the positive photosensitive resin composition according to any one of <1> to <8>,
An exposure step of exposing the film in a pattern with an actinic ray;
A development step of developing the exposed film with an aqueous developer to form a pattern; and
A baking step of heating the pattern;
A pattern forming method including:
<16> The pattern forming method according to <15>, including a post-exposure step of exposing the pattern with actinic rays after the development step and before the baking step.
<17> a step of producing a structure using the pattern produced by the pattern forming method according to <15> or <16> as a sacrificial layer when the structure is laminated; and
And removing the sacrificial layer by plasma treatment.
<18> a step of performing dry etching using the pattern produced by the pattern forming method according to <15> or <16> as a resist for dry etching; and
Removing the pattern by plasma treatment or chemical treatment;
A dry etching method including:
<19> a step of performing wet etching using the pattern produced by the pattern forming method according to <15> or <16> as a resist for wet etching; and
Removing the pattern by plasma treatment or chemical treatment;
A wet etching method including:
<20> Any of <1> to <8>, including producing an acrylic resin by using a chain transfer agent having a carboxyl group at the time of polymerization of the polymerizable monomer or using a polymerization initiator having a carboxyl group A method for producing the positive photosensitive resin composition according to claim 1.

  According to the present invention, it is possible to provide a positive photosensitive resin composition capable of forming a rectangle or a profile close to a rectangle even after the formed pattern is baked. It is particularly suitable for thick film resist applications that require rectangularity.

It is a schematic diagram which shows an example whose pattern cross-sectional profile after heat processing is favorable. It is a schematic diagram which shows an example in which the pattern cross-sectional profile after heat processing is unsatisfactory. It is a schematic diagram which shows an example of the pattern cross-sectional profile after heat processing.

Hereinafter, the positive photosensitive resin composition of the present invention will be described in detail.
In the present invention, the description of “lower limit to upper limit” representing a numerical range represents “lower limit or higher and lower limit or lower”, and the description of “upper limit to lower limit” represents “lower limit or higher and lower limit or higher”. That is, it represents a numerical range including an upper limit and a lower limit.
In the description of the group (atomic group) in this specification, the description which does not describe substitution and unsubstituted includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
In the present specification, “a repeating unit derived from (meth) acrylic acid or an ester thereof” is also referred to as an “acrylic repeating unit”. (Meth) acrylic acid is a generic term for methacrylic acid and acrylic acid.

<Positive photosensitive resin composition>
The positive photosensitive resin composition of the present invention (hereinafter also simply referred to as “photosensitive resin composition”) contains a carboxyl group at the end of the main chain and has a 3-membered ring and / or a 4-membered ring. A positive photosensitive resin composition comprising an acrylic resin containing a repeating unit having an ether group, comprising an acrylic resin that is insoluble or hardly soluble in an alkali developer and becomes soluble in an alkali developer by the action of an acid, A chemical amplification type positive photosensitive resin composition (chemical amplification type positive photosensitive resin composition) is particularly preferable.
The acrylic resin used in the present invention contains a carboxyl group at the end of the main chain and contains a repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group, and is insoluble or hardly soluble in an alkaline developer. It is a resin (also referred to as “specific polymer” or “polymer A”) that is soluble in an alkali developer by the action of an acid.
The acrylic resin used in the present invention preferably contains a residue in which a carboxy group or a phenolic hydroxyl group is protected with an acid-decomposable group, and the residue decomposes (deprotects) the acid-decomposable group with an acid. Thus, a carboxy group or a phenolic hydroxyl group can be generated. In the present invention, it is preferable to include a repeating unit (a1) containing a residue in which a carboxy group or a phenolic hydroxyl group is protected with an acid-decomposable group.
The “repeating unit” in the present invention includes not only a structural unit formed from one monomer molecule but also a structural unit obtained by modifying a structural unit formed from one monomer molecule by a polymer reaction or the like.

The polymer A is preferably a resin that is insoluble in alkali and becomes alkali-soluble when the acid-decomposable group in the repeating unit (a1) is decomposed.
The term “alkali-soluble” in the present invention refers to a coating film (thickness 4 μm) of the compound (resin) formed by applying a solution of the compound (resin) on a substrate and heating at 90 ° C. for 2 minutes. ) In a 0.4 wt% tetramethylammonium hydroxide aqueous solution at 23 ° C. is 0.01 μm / second or more. “Alkali insoluble” means that the solution of the compound (resin) is a substrate. The dissolution rate of a coating film (thickness: 4 μm) of the compound (resin) formed by coating on the substrate and heating at 90 ° C. for 2 minutes in a 0.4 wt% tetramethylammonium hydroxide aqueous solution at 23 ° C. It means less than 0.01 μm / second, preferably less than 0.005 μm / second.

The weight average molecular weight (Mw) of the polymer A is preferably 5,000 or more, more preferably 7,000 or more, and most preferably 10,000 or more. Further, it is preferably 1,000,000 or less, more preferably 80,000 or less, and further preferably 60,000 or less. Within the above range, a better rectangle or a profile close to a rectangle can be obtained even after the baking step. Further, when the weight average molecular weight is 12,000 or more, the shape change in the baking process is small, and in particular, a rectangle or a profile close to a rectangle can be obtained. Further, when the weight average molecular weight is 80,000 or less, the pattern forming property during development is more excellent.
The weight average molecular weight is a value in terms of polystyrene measured by GPC (gel permeation chromatography). It is preferable to use THF as the solvent and TSKgel SuperHZ3000 and TSKgel SuperHZM-M (both manufactured by Tosoh Corporation) as the column.

  The polymer A is an acrylic polymer. The “acrylic polymer” in the present invention is an addition polymerization type resin, is a polymer containing a repeating unit derived from (meth) acrylic acid or an ester thereof, and is derived from (meth) acrylic acid or an ester thereof. You may have repeating units other than a repeating unit, for example, the repeating unit derived from styrene, the repeating unit derived from a vinyl compound, etc. Moreover, the polymer A may contain both the repeating unit derived from (meth) acrylic acid and the repeating unit derived from (meth) acrylic acid ester. In this invention, it is preferable that 90 mol% or more of the repeating unit which comprises the polymer A is a repeating unit derived from (meth) acrylic acid or its ester.

<Repeating unit (a1) having a residue in which a carboxy group or a phenolic hydroxyl group is protected with an acid-decomposable group>
The polymer A more preferably has a repeating unit (a1) having a residue in which a carboxy group or a phenolic hydroxyl group is protected with an acid-decomposable group.
When the polymer A has the repeating unit (a1), a highly sensitive photosensitive resin composition can be obtained. A repeating unit having a residue in which a carboxy group is protected with an acid-decomposable group is characterized by faster development than a repeating unit having a residue in which a phenolic hydroxyl group is protected with an acid-decomposable group. Therefore, a repeating unit having a residue in which a carboxy group is protected with an acid-decomposable group is preferable for rapid development. Conversely, when it is desired to slow development, it is preferable to use a repeating unit having a residue in which a phenolic hydroxyl group is protected with an acid-decomposable group.

[Repeating unit (a1-1) having a residue in which a carboxy group is protected with an acid-decomposable group]
As the acid-decomposable group, known acid-decomposable groups in the positive resist for KrF and the positive resist for ArF can be used and are not particularly limited. Conventionally, as an acid-decomposable group, a group that is relatively easily decomposed by an acid (for example, an acetal functional group such as a tetrahydropyranyl group) or a group that is relatively difficult to be decomposed by an acid (for example, a tert-butyl ester group, a tert-butyl ester group, -Tert-butyl functional groups such as butyl carbonate groups) are known.
Among these acid-decomposable groups, the basic physical properties of the resist, particularly the sensitivity and pattern, should be a residue having a residue in which the carboxy group is protected with an acetal or a residue in which the carboxy group is protected with a ketal. From the viewpoints of shape, contact hole formability, and storage stability of the photosensitive resin composition, it is preferable. Furthermore, it is more preferable from a sensitivity viewpoint that a carboxyl group is a residue protected by the acetal or ketal represented by a following formula (a1-1) among acid-decomposable groups. In addition, when the carboxy group is an acetal or ketal-protected residue represented by the following formula (a1-1), the entire residue is —C (═O) —O—CR ¹ R ² ( OR ³ ).

（式（ａ１−１）中、Ｒ¹およびＲ²は、それぞれ独立に水素原子またはアルキル基を表し、ただし、Ｒ¹とＲ²とが共に水素原子の場合を除く。Ｒ³は、アルキル基を表す。Ｒ¹またはＲ²と、Ｒ³とが連結して環状エーテルを形成してもよい。また、波線部分は、他の構造との
結合位置を表す。）

(In formula (a1-1), R ¹ and R ² each independently represents a hydrogen atom or an alkyl group, except that R ¹ and R ² are both hydrogen atoms, and R ³ represents an alkyl group. R ¹ or R ² and R ³ may be linked to form a cyclic ether, and the wavy line represents the bonding position with another structure.)

In formula (a1-1), R ^{1 to} R ³ each independently represents a hydrogen atom or an alkyl group, and the alkyl group may be linear, branched or cyclic. Here, both R ¹ and R ² do not represent a hydrogen atom, and at least one of R ¹ and R ² represents an alkyl group.
In formula (a1-1), when R ¹ , R ² and R ³ represent an alkyl group, the alkyl group may be linear, branched or cyclic.
The linear or branched alkyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, and still more preferably 1 to 4 carbon atoms. . Specifically, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, neopentyl group, n Examples include -hexyl group, texyl group (2,3-dimethyl-2-butyl group), n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, and n-decyl group.
The cyclic alkyl group preferably has 3 to 12 carbon atoms, more preferably 4 to 8 carbon atoms, and still more preferably 4 to 6 carbon atoms. Examples of the cyclic alkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a norbornyl group, and an isobornyl group.

The alkyl group may have a substituent, and examples of the substituent include a halogen atom, an aryl group, and an alkoxy group. When it has a halogen atom as a substituent, R ¹ , R ² and R ³ become a haloalkyl group, and when it has an aryl group as a substituent, R ¹ , R ² and R ³ become an aralkyl group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and among these, a fluorine atom or a chlorine atom is preferable.
Moreover, as said aryl group, a C6-C20 aryl group is preferable and a C6-C12 aryl group is more preferable. Specific examples include a phenyl group, an α-methylphenyl group, and a naphthyl group.
As the aralkyl group, an aralkyl group having 7 to 32 carbon atoms is preferable, and an aralkyl group having 7 to 20 carbon atoms is more preferable. Specific examples include a benzyl group, an α-methylbenzyl group, a phenethyl group, and a naphthylmethyl group.
The alkoxy group is preferably an alkoxy group having 1 to 6 carbon atoms, more preferably an alkoxy group having 1 to 4 carbon atoms, and further preferably a methoxy group or an ethoxy group.
Further, when the alkyl group is a cycloalkyl group, the cycloalkyl group may have a linear or branched alkyl group having 1 to 10 carbon atoms as a substituent, and the alkyl group is linear Or a branched alkyl group, it may have a cycloalkyl group having 3 to 12 carbon atoms as a substituent.
These substituents may be further substituted with the above substituents.

In Formula (a1-1), when R ¹ , R ² and R ³ represent an aryl group, the aryl group preferably has 6 to 12 carbon atoms, more preferably 6 to 10 carbon atoms. preferable. The aryl group may have a substituent, and preferred examples of the substituent include an alkyl group having 1 to 6 carbon atoms. Examples of the aryl group include a phenyl group, a tolyl group, a silyl group, a cumenyl group, and a 1-naphthyl group.
R ¹ , R ² and R ³ can be bonded to each other to form a ring together with the carbon atom to which they are bonded. Examples of the ring structure when R ¹ and R ² , R ¹ and R ^3, or R ² and R ³ are bonded include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a tetrahydrofuranyl group, an adamantyl group, and a tetrahydro group. A pyranyl group etc. can be mentioned.
In formula (a1-1), it is preferable that either R ¹ or R ² is a hydrogen atom or a methyl group.

As the radical polymerizable monomer used for forming the repeating unit having the residue represented by the formula (a1-1), a commercially available one may be used, or one synthesized by a known method may be used. You can also. For example, it can be synthesized by reacting (meth) acrylic acid with vinyl ether in the presence of an acid catalyst.
In the above synthesis, (meth) acrylic acid may be previously copolymerized with other monomers and then reacted with vinyl ether in the presence of an acid catalyst.

（上記式中、Ｒ¹は、それぞれ、水素原子または炭素数１〜４のアルキル基を表し、Ｌiはカルボニル基またはフェニレン基を表し、Ｒ²はそれぞれ、炭素数１〜４のアルキル基を表す。ｎ１およびｎ２はそれぞれ１〜５の整数であり、ｎ３は１〜４の整数であり、ｎ４は１〜３の整数である。）
Ｒ¹は、それぞれ、水素原子または炭素数１〜４のアルキル基を表し、水素原子またはメチル基が好ましく、メチル基がさらに好ましい。
Ｌiはカルボニル基またはフェニレン基を表し、カルボニル基がより好ましい。
Ｒ²はそれぞれ、水素原子または炭素数１〜４のアルキル基を表し、水素原子またはメチル基が好ましく、何れも水素原子であることがより好ましい。
ｎ１、ｎ２、ｎ３およびｎ４は、それぞれ、０が好ましい。
上記の中でも、特に、（１）、（２）、（５）または（７）が好ましく、（２）、または（７）がさらに好ましく、（７）が特に好ましい。

(In the above formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, Li represents a carbonyl group or a phenylene group, and R ² represents an alkyl group having 1 to 4 carbon atoms, respectively. N1 and n2 are each an integer of 1 to 5, n3 is an integer of 1 to 4, and n4 is an integer of 1 to 3.
R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom or a methyl group, and more preferably a methyl group.
Li represents a carbonyl group or a phenylene group, and a carbonyl group is more preferable.
R ² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.
n1, n2, n3 and n4 are each preferably 0.
Among these, (1), (2), (5) or (7) is particularly preferable, (2) or (7) is more preferable, and (7) is particularly preferable.

  Preferable specific examples of the repeating unit (a1-1) having a residue in which a carboxy group is protected with an acid-decomposable group include the following repeating units. R represents a hydrogen atom or a methyl group. Among these, from the viewpoint of sensitivity, the repeating unit (a1-1-1), the repeating unit (a1-1-2), and the repeating unit (a1-1-7) are preferable, and the repeating unit (a1-1-2) and the repeating unit are preferable. The unit (a1-1-7) is more preferable.

<Repeating unit (a1-2) having a residue in which a phenolic hydroxyl group is protected with an acid-decomposable group>
As the acid-decomposable group, a known group can be used as described above, and is not particularly limited. Among acid-decomposable groups, the basic physical properties of the resist, especially the sensitivity and pattern shape, should be a residue having a phenolic hydroxyl group-protected residue with an acetal or a phenolic hydroxyl group-protected residue with a ketal. From the viewpoint of storage stability of the photosensitive resin composition and formability of the contact hole. Furthermore, among the acid-decomposable groups, the phenolic hydroxyl group is more preferably a residue protected with an acetal or ketal represented by the above formula (a1-1) from the viewpoint of sensitivity. When the phenolic hydroxyl group is a residue protected with an acetal or ketal represented by the above formula (a1-1), the entire residue is -Ar-O-CR ¹ R ² (OR ³ ). It has a structure. Ar represents an arylene group.
Preferred examples of the acetal ester structure for protecting the phenolic hydroxyl group include a combination of R ¹ = R ² = R ³ = methyl group, R ¹ = R ² = methyl group, and R ³ = benzyl group.

  Moreover, as a radically polymerizable monomer used for forming a repeating unit having a residue in which a phenolic hydroxyl group is protected with an acetal or ketal, a 1-alkoxyalkyl protected form of 4-hydroxyphenyl methacrylate, 4- Tetrahydropyranyl protected form of hydroxyphenyl methacrylate, 1-alkoxyalkyl protected form of 4-hydroxybenzoic acid (1-methacryloyloxymethyl) ester, Tetrahydropyranyl protected form of 4-hydroxybenzoic acid (1-methacryloyloxymethyl) ester 4-hydroxybenzoic acid (2-methacryloyloxyethyl) ester 1-alkoxyalkyl protected, 4-hydroxybenzoic acid (2-methacryloyloxyethyl) ester tetrahydropyranyl protected, 4-hydro 1-alkoxyalkyl protected form of benzoic acid (3-methacryloyloxypropyl) ester, tetrahydropyranyl protected form of 4-hydroxybenzoic acid (3-methacryloyloxypropyl) ester, 4-hydroxybenzoic acid (3-methacryloyloxy) A 2-hydroxypropyl) ester 1-alkoxyalkyl protector and a 4-hydroxybenzoic acid (3-methacryloyloxy-2-hydroxypropyl) ester tetrahydropyranyl protector are preferred from the viewpoint of transparency.

  Specific examples of the acetal protecting group and the ketal protecting group for the phenolic hydroxyl group include 1-alkoxyalkyl groups, such as 1-ethoxyethyl group, 1-methoxyethyl group, 1-n-butoxyethyl group, 1- Isobutoxyethyl group, 1- (2-chloroethoxy) ethyl group, 1- (2-ethylhexyloxy) ethyl group, 1-n-propoxyethyl group, 1-cyclohexyloxyethyl group, 1- (2-cyclohexylethoxy) An ethyl group, 1-benzyloxyethyl group, etc. can be mentioned, These can be used individually or in combination of 2 or more types.

  A commercially available thing may be used for the radically polymerizable monomer used in order to form a repeating unit (a1-2), and what was synthesize | combined by the well-known method can also be used. For example, it can be synthesized by reacting a compound having a phenolic hydroxyl group with vinyl ether in the presence of an acid catalyst. In the above synthesis, a monomer having a phenolic hydroxyl group may be previously copolymerized with another monomer, and then reacted with vinyl ether in the presence of an acid catalyst.

  Preferable specific examples of the repeating unit (a1-2) include the following repeating units, but the present invention is not limited thereto.

  The content of the repeating unit (a1) in the polymer A is preferably from 3 to 70 mol%, more preferably from 5 to 60 mol%, more preferably from 20 to 45 mol, based on the total repeating units of the polymer A, from the viewpoint of sensitivity. % Is more preferable.

（一般式（１）中、Ｒ¹は水素原子またはアルキル基を表し、Ｌは２価の連結基を表し、Ｒ²〜Ｒ⁴は、それぞれ、水素原子、アルキル基、またはフェニル基を表す。ｎは１または２を表す。Ｒ²、Ｒ³またはＲ⁴が、Ｌが有する置換基と結合して環を形成してもよい。）
一般式（１）において、ｎが１のとき、Ｒ³およびＲ⁴で表される基はそれぞれ１つずつであり、ｎが２のとき、Ｒ³およびＲ⁴で表される基はそれぞれ２つずつとなる。 <Repeating unit (a2) having a 3-membered ring and / or a 4-membered cyclic ether group>
Examples of the cyclic ether group in the repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group used in the present invention include an epoxy group and an oxetanyl group. More preferably, the cyclic ether group has the following structure.
General formula (1)

(In General Formula (1), R ¹ represents a hydrogen atom or an alkyl group, L represents a divalent linking group, and R ^{2 to} R ⁴ each represents a hydrogen atom, an alkyl group, or a phenyl group. n represents 1 or 2. R ² , R ^3, or R ⁴ may combine with a substituent of L to form a ring.
In the general formula (1), when n is 1, the groups represented by R ³ and R ⁴ are each one, and when n is 2, the groups represented by R ³ and R ⁴ are each 2 One by one.

R ¹ is preferably a hydrogen atom or a methyl group, and more preferably a methyl group.
L is preferably an aryl group, an alkyl group, an ether bond, an ester bond, or a divalent linking group containing a combination thereof. Examples of the substituent that L has include an alkyl group, a phenyl group, an alkoxy group, a fluorine atom, and a bromine atom.
R ² is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. The alkyl group may have a substituent.
R ³ and R ⁴ are more preferably hydrogen atoms.

Examples of the radical polymerizable monomer used for forming the repeating unit (a2) are preferably a monomer containing a methacrylic ester structure and a monomer containing an acrylic ester structure.
The group having an epoxy group is not particularly limited as long as it has an epoxy ring, but a glycidyl group and a 3,4-epoxycyclohexylmethyl group can be preferably exemplified.
The group having an oxetanyl group is not particularly limited as long as it has an oxetane ring, but a (3-ethyloxetane-3-yl) methyl group can be preferably exemplified.
Specific examples of the radical polymerizable monomer used to form the repeating unit having an epoxy group include, for example, glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, and glycidyl α-n-propyl acrylate. Glycidyl α-n-butyl acrylate, 3,4-epoxybutyl acrylate, 3,4-epoxybutyl methacrylate, acrylate-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl, α-ethylacrylic acid-6,7-epoxyheptyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, cycloaliphatic described in paragraphs 0031 to 0035 of Japanese Patent No. 4168443 Compounds containing an epoxy skeleton It is.
Examples of the radical polymerizable monomer used to form a repeating unit having an oxetanyl group include, for example, (meth) acrylic acid having an oxetanyl group described in paragraphs 0011 to 0016 of JP-A No. 2001-330953. Examples include esters.
Among these monomers, more preferred are glycidyl methacrylate, glycidyl acrylate, compounds containing an alicyclic epoxy skeleton described in paragraphs 0034 to 0035 of Japanese Patent No. 4168443 and JP-A No. 2001-330953. Examples include (meth) acrylic acid esters having an oxetanyl group described in paragraphs 0011 to 0016 of the publication.
Particularly preferable from the viewpoint of heat-resistant transparency is a repeating unit derived from either (3-ethyloxetane-3-yl) methyl acrylate or methyl (3-ethyloxetane-3-yl) methacrylate. is there.
These repeating units (a2) can be used singly or in combination of two or more.

Preferable specific examples of the repeating unit (a2) include the following repeating units, but are not limited to the following structures.

  From the viewpoint of sensitivity, the content of the repeating unit (a2) in the polymer A is preferably from 3 to 90 mol%, more preferably from 5 to 80 mol%, more preferably from 20 to 70 mol%, based on all repeating units of the polymer A. % Is more preferable, and 25 to 40 mol% is particularly preferable.

<Repeating unit having a ring structure (a4)>
The polymer A preferably contains a repeating unit (a4) having a ring structure from the viewpoint of improving dry etching resistance and chemical resistance. However, (a4) is intended to exclude those corresponding to (a1) and (a2) above.
Examples of the monomer forming the repeating unit (a4) include cyclic alkyl (meth) acrylates such as styrenes, dicyclopentanyl (meth) acrylate, cyclohexyl (meth) acrylate, and cyclohexyl (meth) acrylate. Examples thereof include esters and unsaturated aromatic compounds.
Preferred examples of the repeating unit (a4) having a ring structure include repeating units represented by the following formula (a4-1) or formula (a4-2).

（式中、Ｒ^Aは水素原子または炭素原子数１〜６のアルキル基を表す。Ｒは水素原子または置換基を示す。） Formula (a4-1)

(In the formula, R ^A represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R represents a hydrogen atom or a substituent.)

R ^A in the formula (a4-1) is preferably a hydrogen atom or a methyl group, particularly preferably a hydrogen atom, from the viewpoint of the uniformity of the polymerization rate of each monomer during polymerization. R is preferably a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, a halogen atom or a hydroxyl group, more preferably a hydrogen atom.

（式中、Ｒ^Bは水素原子またはメチル基を表し、Ｘは単結合または炭素原子数１〜４のアルキレン基を表し、環Ａはシクロペンタン環またはシクロペンテン環を表し、環Ａを有していても、有していなくともよい。） Formula (a4-2)

(Wherein, R ^B represents a hydrogen atom or a methyl group, X represents a single bond or an alkylene group having 1 to 4 carbon atoms, ring A represents a cyclopentane ring or a cyclopentene ring, have a ring A Or do not have to.)

R ^B in the formula (a4-2), from the viewpoint of the uniformity of the polymerization rate of each monomer during the polymerization is preferably a methyl group.
X in the formula (a4-2) is preferably a single bond, a methylene group or an ethylene group, and more preferably a single bond.
Ring A in formula (a4-2) preferably has ring A, preferably a cyclopentene ring or a cyclopentane ring, and more preferably a cyclopentane ring. The position of the double bond of the cyclopentene ring in ring A is not particularly limited and may be any position.

  The content of the repeating unit (a4) in the polymer A is preferably 1 to 50 mol%, more preferably 5 to 35 mol%, and particularly preferably 10 to 30 mol% with respect to all the repeating units of the polymer A. By including the repeating unit (a4) at the above ratio, the resulting pattern is excellent in dry etching resistance and chemical resistance.

<Repeating unit (a5) having carboxy group or hydroxyl group>
It is preferable that the polymer A has a repeating unit (a5) having a carboxy group or a hydroxyl group from the viewpoint of developability. However, this is intended to exclude those corresponding to the above (a1), (a2), and (a4).
It is preferable to introduce the repeating unit (a5) in such a range that the polymer A is not alkali-soluble. The content of the repeating unit (a5) in the polymer A is preferably 2 to 20 mol%, more preferably 2 to 15 mol%, and particularly preferably 3 to 15 mol% with respect to all the repeating units of the polymer A. By containing the repeating unit (a5) in the above ratio, high sensitivity is obtained and developability is also improved.

[Repeating unit having a carboxy group (a5-1)]
Examples of the repeating unit (a5-1) having a carboxy group include unsaturated carboxylic acids having at least one carboxy group in the molecule, such as unsaturated monocarboxylic acid, unsaturated dicarboxylic acid, and unsaturated tricarboxylic acid. The repeating unit derived from is mentioned.
As unsaturated carboxylic acid used in order to obtain the repeating unit (a5-1) which has a carboxy group, what is illustrated below is used.
That is, examples of the unsaturated monocarboxylic acid include acrylic acid, methacrylic acid, crotonic acid, α-chloroacrylic acid, and cinnamic acid.
Examples of the unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid.

Moreover, the acid anhydride may be sufficient as unsaturated polyhydric carboxylic acid used in order to obtain the repeating unit (a5-1) which has a carboxy group. Specific examples include maleic anhydride, itaconic anhydride, citraconic anhydride, and the like. The unsaturated polyvalent carboxylic acid may be a mono (2-methacryloyloxyalkyl) ester of a polyvalent carboxylic acid. For example, succinic acid mono (2-acryloyloxyethyl), succinic acid mono (2 -Methacryloyloxyethyl), mono (2-acryloyloxyethyl) phthalate, mono (2-methacryloyloxyethyl) phthalate and the like.
As the unsaturated carboxylic acid, acrylic acid-2-carboxyethyl ester, methacrylic acid-2-carboxyethyl ester, maleic acid monoalkyl ester, fumaric acid monoalkyl ester, 4-carboxystyrene and the like can also be used.
Especially, in order to form the repeating unit (a5-1) which has a carboxy group from a developable viewpoint, it is preferable to use acrylic acid and methacrylic acid.

Moreover, the repeating unit (a5-1) which has a carboxy group can be obtained also by making the repeating unit (a5-2) which has a hydroxyl group mentioned later, and an acid anhydride react.
As the acid anhydride, known ones can be used. Specific examples include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and chlorendic anhydride. Examples include basic acid anhydrides; acid anhydrides such as trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid anhydride, and biphenyl tetracarboxylic acid anhydride. Among these, phthalic anhydride, tetrahydrophthalic anhydride, or succinic anhydride is preferable from the viewpoint of developability.

[Repeating unit having a hydroxyl group (a5-2)]
Examples of the repeating unit (a5-2) having a hydroxyl group include a repeating unit (a5-2-1) having a phenolic hydroxyl group.
Among the repeating units having a hydroxyl group (a5-2), examples of the radical polymerizable monomer used to form the repeating unit having a phenolic hydroxyl group (a5-2-1) include p-hydroxystyrene, Hydroxystyrenes such as α-methyl-p-hydroxystyrene, compounds described in paragraphs 0011 to 0016 of JP-A-2008-40183, and 4-hydroxybenzoic acid derivatives described in paragraphs 0007 to 0010 of Japanese Patent No. 2888454 Preferred examples include an addition reaction product of 4-hydroxybenzoic acid and glycidyl methacrylate, an addition reaction product of 4-hydroxybenzoic acid and glycidyl acrylate, and the like.

  Among radical polymerizable monomers used to form the repeating unit (a5-2-1) having a phenolic hydroxyl group, methacrylic acid, acrylic acid, described in paragraphs 0011 to 0016 of JP2008-40183A Compound, 4-hydroxybenzoic acid derivatives described in paragraphs 0007 to 0010 of Japanese Patent No. 2888454, addition reaction product of 4-hydroxybenzoic acid and glycidyl methacrylate, 4-hydroxybenzoic acid and glycidyl acrylate Addition reactants are more preferred, but methacrylic acid and acrylic acid are particularly preferred from the viewpoint of transparency. These repeating units can be used singly or in combination of two or more.

  Of the repeating units having a hydroxyl group (a5-2), any repeating unit having a hydroxyl group other than the phenolic hydroxyl group (a5-2-2) may be used as long as it is a repeating unit having a hydroxyl group. Preferred examples include repeating units derived from hydroxyl group-containing (meth) acrylic acid esters, (meth) acrylic acid esters of alkyl-terminated polyalkylene glycols, (meth) acrylic acid esters of aryl-terminated polyalkylene glycols, and the like. be able to.

  Examples of the hydroxyl group-containing (meth) acrylic acid ester include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 2,3 (meth) acrylic acid. -Hydroxyalkyl esters of (meth) acrylic acid such as dihydroxypropyl, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, poly (ethylene glycol / propylene glycol)- Mono (meth) acrylate, polyethylene glycol / polypropylene glycol-mono (meth) acrylate, poly (ethylene glycol / tetramethylene glycol) -mono (meth) acrylate, poly (propylene glycol) Le tetramethylene glycol) - mono (meth) acrylate, propylene glycol polybutylene glycol - may be mentioned as preferred examples of the mono (meth) acrylate.

Examples of (meth) acrylic acid esters of alkyl group-terminated polyalkylene glycols include methoxypolyethylene glycol- (meth) acrylate, octoxypolyethyleneglycol-polypropyleneglycol- (meth) acrylate, lauroxypolyethyleneglycol- (meth) acrylate, and steer. Roxypolyethylene glycol- (meth) acrylate can be mentioned as a preferred example.
Examples of the (meth) acrylic acid ester of the aryl group-terminated polyalkylene glycol include, for example, phenoxy polyethylene glycol- (meth) acrylate, phenoxy polyethylene glycol-polypropylene glycol- (meth) acrylate, nonylphenoxy-polyethylene glycol- (meth) acrylate, and nonyl. Preferable examples include phenoxy-polypropylene glycol- (meth) acrylate and nonylphenoxy-poly (ethylene glycol-propylene glycol)-(meth) acrylate.

  Commercially available hydroxyl group-containing (meth) acrylic acid esters, alkyl group-terminated polyalkylene glycol (meth) acrylic acid esters and aryl group-terminated polyalkylene glycol (meth) acrylic acid esters can be used. Representative examples are Blemmer E, Blemmer PE-90, Blemmer PE-200, Blemmer PE-350, Blemmer P, Blemmer PP-1000, Blemmer PP-500, Blemmer PP-800, Blemmer 50 PEP-300, Blemmer 70 PEP- 350B, Blemmer 55PET-800, Blemmer PPT series, Blemmer 10PPB-500B, Blemmer AE-90, Blemmer AE-200, Blemmer AE-400, Blemmer AP-150, Blemmer AP-400, Blemmer AP-550, Blemmer PME-100 , Blemmer PME-200, Blemmer PME-400, Blemmer PME-1000, Blemmer 50POEP-800B, Blemmer PLE-200, Blemmer PSE-4 0, Blemmer PSE-1300, Blemmer PAE-50, Blemmer PAE-100, Blemmer 43PAPE-600B, Blemmer AME-400, Blemmer ALE series, Blemmer ANP-300, Blemmer 75ANP-600, Blemmer AAE-50, Blemmer AAE-300 (Above, manufactured by NOF Corporation).

In the repeating unit (a5-2), the number of hydroxyl groups is preferably 1 to 10, more preferably 1 to 5, and particularly preferably 1 to 3.
When the repeating unit (a5-2) has an alkyleneoxy group, the number of repeating units of the alkyleneoxy group is preferably 1 to 25, more preferably 1 to 15, and most preferably 1 to 10.

Preferable specific examples of the radical polymerizable monomer used for forming the repeating unit (a5-2) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) 3-hydroxypropyl acrylate, 2,3-dihydroxypropyl (meth) acrylate, methoxypolyethylene glycol- (meth) acrylate having 2 to 10 ethylene glycol repeating units, and methoxypolypropylene having 2 to 10 propylene glycol repeating units Glycol- (meth) acrylate, ethylene glycol repeating unit and propylene glycol repeating unit of 2-10 methoxypolyethylene glycol-polypropylene glycol- (meth) acrylate, ethylene glycol repeating unit and pro 2-10 octoxypolyethyleneglycol-polypropyleneglycol- (meth) acrylate, lenglycol repeating unit sum, 2-10 ethylene glycol repeating unit polyethylene glycol mono (meth) acrylate, 2 propylene glycol repeating units 10 polypropylene glycol mono (meth) acrylates, poly (ethylene glycol / propylene glycol) -mono (meth) acrylate with 3 to 10 total of ethylene glycol repeating units and propylene glycol repeating units, ethylene glycol repeating units and propylene glycol Examples include polyethylene glycol / polypropylene glycol / mono (meth) acrylate having 3 to 10 repeating units.
Among these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, ethylene glycol repeating unit Is more preferably 2-10 methoxypolyethylene glycol- (meth) acrylates, more preferably 2-10 octoxypolyethyleneglycol-polypropyleneglycol- (meth) acrylates having a sum of ethylene glycol repeating units and propylene glycol repeating units, ethylene glycol Methoxypolyethylene glycol- (meth) acrylate and 2-hydroxyethyl (meth) acrylate having 2 to 10 repeating units are particularly preferred.
A repeating unit (a5) can be used individually by 1 type or in combination of 2 or more types.

The content of the repeating unit (a5) in the polymer A is preferably 0.5 to 30 mol%, more preferably 0.5 to 25 mol%, and more preferably 1 to 25 mol% with respect to all the repeating units of the polymer A. Is particularly preferred.
The content of the repeating unit (a5) in the polymer A is 3 to 30% by weight, more preferably 3 to 25% by weight, particularly preferably 5 to 25% by weight based on the total weight of the polymer A. . By containing the repeating unit (a5) in the above proportion, the developability is improved and a highly sensitive photosensitive composition can be obtained. In particular, by combining the above-mentioned repeating unit (a2) and repeating unit (a5), a photosensitive resin composition with very high sensitivity can be obtained.

<Other repeating unit (a6)>
The polymer A may contain a repeating unit (a6) other than the repeating units (a1) to (a5) as long as the effects of the present invention are not hindered.
Examples of the radical polymerizable monomer used to form the repeating unit (a6) include the compounds described in paragraphs 0021 to 0024 of Japanese Patent No. 4207604 (however, the above repeating unit ( excluding the monomers forming a1) to (a5)).
The polymer A may have one type of repeating unit (a6) or two or more types.

The content of the repeating unit (a6) in the polymer A is preferably 0 to 40 mol% and more preferably 0 to 10 mol% with respect to all the repeating units of the polymer A.
Moreover, when the polymer A contains the repeating unit (a6), the content of the repeating unit (a5) in the polymer A is preferably 1 to 40 mol% with respect to all the repeating units of the polymer A, 30 mol% is more preferable and 5-25 mol% is especially preferable.
In addition, the weight average molecular weight in this invention is a polystyrene conversion weight average molecular weight by gel permeation chromatography (GPC).

The method for introducing each repeating unit of the polymer A may be a polymerization method or a polymer reaction method.
In the polymerization method, monomers containing a predetermined functional group are synthesized in advance, and then these monomers are copolymerized. That is, radical polymerization used to form the repeating unit (a1), the repeating unit (a2), the repeating unit (a3), the repeating unit (a4), the repeating unit (a5), and, if necessary, the repeating unit (a6). It can be synthesized by polymerizing a radically polymerizable monomer mixture containing a polymerizable monomer in an organic solvent using a radical polymerization initiator.
In the polymer reaction method, after a polymerization reaction is performed, a necessary functional group is introduced into the repeating unit using a reactive group contained in the repeating unit of the obtained copolymer.
The introduction of the above-mentioned repeating units (a1) to (a6) into the polymer A may be a polymerization method or a polymer reaction method, and these two methods may be used in combination.
The polymer A can be used alone or in combination of two or more in the photosensitive resin composition of the present invention.

<Method of introducing a carboxyl group into the resin main chain terminal>
As a method for introducing a carboxyl group into the resin main chain terminal, there are a method using a chain transfer agent having a carboxyl group at the time of polymerization and a method using a polymerization initiator having a carboxyl group.
In the method using a chain transfer agent having a carboxyl group at the time of polymerization, a thiol compound having at least one carboxyl group is used in combination at the time of polymerization. Examples of thiol compounds having at least one carboxyl group include the following.

The chain transfer agent is preferably blended at a ratio of 1/100 to 2/3 mole, more preferably 1/20 to 1/3 mole relative to the initiator amount.
Although the molecular weight is adjusted by the sum of the initiator amount and the chain transfer agent, it is preferably 0.05 to 10 mol%, more preferably 0.1 to 5 mol%, based on the total moles of all monomers.
The reaction temperature for the copolymerization reaction is preferably 50 to 100 ° C, and more preferably 60 to 95 ° C.

As a method of using a polymerization initiator having a carboxyl group, a polymerization initiator having a carboxyl group is used as an initiator at the time of polymerization.
As the polymerization initiator having a carboxyl group, it is widely used. Examples thereof include VA-057 (manufactured by Wako Pure Chemical Industries, Ltd.) and V-501 (manufactured by Wako Pure Chemical Industries, Ltd.).

The polymerization initiator is preferably 0.05 to 10 mol%, more preferably 0.1 to 5 mol%, based on 100 mol of the polymerizable monomer.
The reaction temperature for the copolymerization reaction is preferably 50 to 100 ° C, and more preferably 60 to 100 ° C.

The positive photosensitive resin composition of the present invention is preferably used for an etching resist, and more preferably a photosensitive resin composition for a thick film etching resist having a film thickness of 4 to 100 μm.
Moreover, the positive photosensitive resin composition of the present invention is preferably a positive photosensitive resin composition capable of forming a baking cross-sectional shape having a taper angle of 70 ° or more.
The “taper angle” is an angle formed between the side surface of the pattern and the substrate plane on which the pattern is formed in the cross-sectional shape after the pattern is formed and the baking process is performed. When the cross-sectional shape of the side surface of the pattern is not a straight line, the angle between the tangent line at the point where the film thickness on the pattern is half and the substrate plane is the cross-sectional shape. In addition, even when the cross-sectional shape of the side surface of the pattern is a semicircle or an arcuate shape and the upper surface of the pattern is not recognized, the tangent line and the plate substrate at the middle point between the uppermost part of the film and the substrate, that is, at the point of 1/2 the film thickness The angle with the plane.
As a specific example, θ in each pattern cross-sectional shape shown in FIGS. 1, 2, and 3 is a taper angle.
In the example of FIG. 3, since the pattern cross-sectional shape is not observed and the upper surface of the pattern is not recognized, the angle between the tangent at the top of the film and the midpoint of the substrate, that is, the half of the film thickness, and the plane of the plate substrate is θ It is said.

The content of the polymer A in the photosensitive resin composition of the present invention is preferably 20 to 99% by weight, and preferably 40 to 97% by weight, based on the total solid content of the photosensitive resin composition. Is more preferable, 50 to 95% by weight is further preferable, and 50 to 80% by weight is particularly preferable. When the content is within this range, the pattern formability upon development is good. In addition, the solid content amount of the photosensitive resin composition represents an amount excluding volatile components such as a solvent.
In addition, in the photosensitive resin composition of this invention, you may use resin other than the polymer A together in the range which does not inhibit the effect of this invention. However, the content of the resin other than the polymer A is preferably smaller than the content of the polymer A from the viewpoint of developability.

  Hereinafter, other components constituting the photosensitive resin composition will be described.

<(B) Photoacid generator>
The photosensitive resin composition of the present invention contains (B) a photoacid generator.
The photoacid generator is preferably a compound that reacts with an actinic ray having a wavelength of 300 nm or more, preferably 300 to 450 nm, and generates an acid, but is not limited to its chemical structure. Further, a photoacid generator that is not directly sensitive to an actinic ray having a wavelength of 300 nm or more can also be used as a sensitizer if it is a compound that reacts with an actinic ray having a wavelength of 300 nm or more and generates an acid when used in combination with a sensitizer. It can be preferably used in combination.
As the photoacid generator, a photoacid generator that generates an acid having a pKa of 4 or less is preferable, and a photoacid generator that generates an acid having a pKa of 3 or less is more preferable.
Examples of photoacid generators include trichloromethyl-s-triazines, onium salts such as sulfonium and iodonium salts, quaternary ammonium salts, diazomethane compounds, imide sulfonate compounds, and oxime sulfonate compounds. . Among these, from the viewpoint of high sensitivity, onium salts and / or oxime sulfonate compounds are preferable, and oxysim sulfonate compounds are more preferable. These photoacid generators can be used singly or in combination of two or more.

  The photosensitive resin composition of the present invention preferably contains an oxime sulfonate compound having at least one oxime sulfonate residue represented by the following formula (1) as (Component B) a photoacid generator.

例えば、特開２０１０−２８２１７８号公報の段落番号００６０〜００６１の記載を参酌できる。

For example, the description of paragraph numbers 0060 to 0061 of JP 2010-282178 A can be referred to.

  As the compound having at least one oxime sulfonate residue represented by the formula (1), an oxime sulfonate compound represented by the following formula (OS-3), formula (OS-4) or formula (OS-5) It is preferable that

（式（ＯＳ−３）〜（ＯＳ−５）中、Ｒ¹はアルキル基、アリール基、またはヘテロアリール基を表し、複数存在するＲ²はそれぞれ独立に、水素原子、アルキル基、アリール基、またはハロゲン原子を表し、複数存在するＲ⁶はそれぞれ独立に、ハロゲン原子、アルキル基、アルキルオキシ基、スルホン酸基、アミノスルホニル基、またはアルコキシスルホニル基を表し、ＸはＯまたはＳを表し、ｎは１または２を表し、ｍは０〜６の整数を表す。）

(In the formulas (OS-3) to (OS-5), R ¹ represents an alkyl group, an aryl group, or a heteroaryl group, and a plurality of R ² are each independently a hydrogen atom, an alkyl group, an aryl group, Or a plurality of R ^{6 s} each independently represents a halogen atom, an alkyl group, an alkyloxy group, a sulfonic acid group, an aminosulfonyl group, or an alkoxysulfonyl group, X represents O or S, n Represents 1 or 2, m represents an integer of 0-6.)

In the formulas (OS-3) to (OS-5), the alkyl group, aryl group or heteroaryl group represented by R ¹ may have a substituent.
In the formulas (OS-3) to (OS-5), the alkyl group represented by R ¹ is preferably an alkyl group having 1 to 30 carbon atoms which may have a substituent.
In the formulas (OS-3) to (OS-5), the aryl group represented by R ¹ is preferably an aryl group having 6 to 30 carbon atoms in total which may have a substituent.
In the formulas (OS-3) to (OS-5), the heteroaryl group represented by R ¹ is preferably a heteroaryl group having a total carbon number of 4 to 30 which may have a substituent. There may be at least one heteroaromatic ring. For example, the heteroaromatic ring and the benzene ring may be condensed.
Examples of the substituent that the alkyl group, aryl group or heteroaryl group represented by R ¹ may have include a halogen atom, alkyloxy group, aryloxy group, alkylthio group, arylthio group, alkyloxycarbonyl group, aryl Examples thereof include an oxycarbonyl group and an aminocarbonyl group.

In the formulas (OS-3) to (OS-5), R ² is preferably a hydrogen atom, an alkyl group, or an aryl group, and more preferably a hydrogen atom or an alkyl group.
In the formulas (OS-3) to (OS-5), it is preferable that one or two of R ² present in the compound is an alkyl group, an aryl group or a halogen atom, and one is an alkyl group. More preferably an aryl group or a halogen atom, and particularly preferably one is an alkyl group and the rest is a hydrogen atom.
In the formulas (OS-3) to (OS-5), the alkyl group or aryl group represented by R ² may have a substituent.
Examples of the substituent that the alkyl group or aryl group represented by R ² may have include the same groups as the substituent that the alkyl group or aryl group in R ¹ may have.

In the formulas (OS-3) to (OS-5), the alkyl group represented by R ² is preferably an alkyl group having 1 to 12 carbon atoms which may have a substituent. It is more preferable that it is a C1-C6 alkyl group which may have a group.
As the alkyl group represented by R ² , a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-hexyl group are preferable, and a methyl group is more preferable.

In the formulas (OS-3) to (OS-5), the aryl group represented by R ² is preferably an aryl group having 6 to 30 carbon atoms in total which may have a substituent.
The aryl group represented by R ² is preferably a phenyl group, a p-methylphenyl group, an o-chlorophenyl group, a p-chlorophenyl group, an o-methoxyphenyl group, or a p-phenoxyphenyl group.
In the formulas (OS-3) to (OS-5), X represents O or S, and is preferably O.
In the formulas (OS-3) to (OS-5), the ring containing X as a ring member is a 5-membered ring or a 6-membered ring.
In the formulas (OS-3) to (OS-5), n represents 1 or 2, and when X is O, n is preferably 1, and when X is S, n is 2 is preferred.

In the formulas (OS-3) to (OS-5), the alkyl group and alkyloxy group represented by R ⁶ may have a substituent.
In the formulas (OS-3) to (OS-5), the alkyl group represented by R ⁶ is preferably an alkyl group having 1 to 30 carbon atoms which may have a substituent.
As the alkyloxy group represented by R ⁶ , a methyloxy group, an ethyloxy group, a butyloxy group, a hexyloxy group, a phenoxyethyloxy group, a trichloromethyloxy group, or an ethoxyethyloxy group is preferable.
Examples of the aminosulfonyl group for R ⁶ include a methylaminosulfonyl group, a dimethylaminosulfonyl group, a phenylaminosulfonyl group, a methylphenylaminosulfonyl group, and an aminosulfonyl group.
Examples of the alkoxysulfonyl group represented by R ⁶ include a methoxysulfonyl group, an ethoxysulfonyl group, a propyloxysulfonyl group, and a butyloxysulfonyl group.

Examples of the substituent that the alkyl group or alkyloxy group represented by R ⁶ may have include a halogen atom, an alkyloxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkyloxycarbonyl group, and an aryloxycarbonyl group. And aminocarbonyl group.

  In the formulas (OS-3) to (OS-5), m represents an integer of 0 to 6, preferably an integer of 0 to 2, more preferably 0 or 1, and 0. It is particularly preferred.

  The compound represented by the formula (OS-3) is particularly preferably a compound represented by the following formula (OS-6), (OS-10), or (OS-11). The compound represented by OS-4) is particularly preferably a compound represented by the following formula (OS-7), and the compound represented by the formula (OS-5) is represented by the following formula (OS-8). ) Or (OS-9) is particularly preferable.

（式（ＯＳ−６）〜（ＯＳ−１１）中、Ｒ¹はアルキル基、アリール基またはヘテロアリール基を表し、Ｒ⁷は、水素原子または臭素原子を表し、Ｒ⁸は水素原子、炭素数１〜８のアルキル基、ハロゲン原子、クロロメチル基、ブロモメチル基、ブロモエチル基、メトキシメチル基、フェニル基またはクロロフェニル基を表し、Ｒ⁹は水素原子、ハロゲン原子、メチル基またはメトキシ基を表し、Ｒ¹⁰は水素原子またはメチル基を表す。）

(In formulas (OS-6) to (OS-11), R ¹ represents an alkyl group, an aryl group, or a heteroaryl group, R ⁷ represents a hydrogen atom or a bromine atom, R ⁸ represents a hydrogen atom, 1 to 8 represents an alkyl group, a halogen atom, a chloromethyl group, a bromomethyl group, a bromoethyl group, a methoxymethyl group, a phenyl group or a chlorophenyl group, R ⁹ represents a hydrogen atom, a halogen atom, a methyl group or a methoxy group; ¹⁰ represents a hydrogen atom or a methyl group.)

R ¹ in the formulas (OS-6) to (OS-11) has the same meaning as R ¹ in the formulas (OS-3) to (OS-5), and preferred embodiments thereof are also the same.
R ⁷ in the formula (OS-6) represents a hydrogen atom or a bromine atom, and is preferably a hydrogen atom.
R ⁸ in the above formulas (OS-6) to (OS-11) is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a halogen atom, a chloromethyl group, a bromomethyl group, a bromoethyl group, a methoxymethyl group, a phenyl group or Represents a chlorophenyl group, preferably an alkyl group having 1 to 8 carbon atoms, a halogen atom or a phenyl group, more preferably an alkyl group having 1 to 8 carbon atoms, and an alkyl group having 1 to 6 carbon atoms. More preferred is a methyl group.
R ⁹ in the formulas (OS-8) and (OS-9) represents a hydrogen atom, a halogen atom, a methyl group or a methoxy group, and is preferably a hydrogen atom.
R ¹⁰ in the formulas (OS-8) to (OS-11) represents a hydrogen atom or a methyl group, and is preferably a hydrogen atom.
In the oxime sulfonate compound, the oxime steric structure (E, Z) may be either one or a mixture.

  Specific examples of the oxime sulfonate compounds represented by the formulas (OS-3) to (OS-5) include the following exemplary compounds, but the present invention is not limited thereto.

  As another preferred embodiment of the oxime sulfonate compound having at least one oxime sulfonate residue represented by the formula (1), a compound represented by the following formula (OS-1) may be mentioned.

In the formula (OS-1), R ¹ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, an alkoxycarbonyl group, an acyl group, a carbamoyl group, a sulfamoyl group, a sulfo group, a cyano group, an aryl group, or heteroaryl. Represents a group. R ² represents an alkyl group or an aryl group.
Is -O X -, - S -, - NH -, - NR 5 -, - CH 2 -, - CR 6 H-, or -CR ⁶ R ⁷ - represents, R ⁵ to R ⁷ is an alkyl group or, Represents an aryl group.
R ^{21 to} R ²⁴ are each independently a hydrogen atom, halogen atom, alkyl group, alkenyl group, alkoxy group, amino group, alkoxycarbonyl group, alkylcarbonyl group, arylcarbonyl group, amide group, sulfo group, cyano group, Or represents an aryl group. Two of R ^{21 to} R ²⁴ may be bonded to each other to form a ring.
As R ^{21 to} R ²⁴ , a hydrogen atom, a halogen atom, and an alkyl group are preferable, and an embodiment in which at least two of R ^{21 to} R ²⁴ are bonded to each other to form an aryl group is also preferable. Among these, an embodiment in which R ^{21 to} R ²⁴ are all hydrogen atoms is preferable from the viewpoint of sensitivity.
Any of the above-described substituents may further have a substituent.

  The compound represented by the formula (OS-1) is more preferably a compound represented by the following formula (OS-2).

In the formula ^{(OS-2), R 1} , R 2, R 21 ~R 24 are respectively synonymous with ^{R 1, R 2, R 21} ~R 24 in the general formula (OS-1), preferred examples thereof are also The same is true.
Among these, an embodiment in which R ¹ in the formula (OS-1) and the formula (OS-2) is a cyano group or an aryl group is more preferable, represented by the formula (OS-2), and R ¹ is a cyano group, The embodiment which is a phenyl group or a naphthyl group is most preferable.

  In the oxime sulfonate compound, the steric structure (E, Z, etc.) of the oxime or benzothiazole ring may be either one or a mixture.

  The oxime sulfonate compound is preferably an oxime sulfonate compound represented by the following formula (B-1).

（式中、Ｒ^B4は水素原子又はメチル基を表し、Ｒ^B5は炭素数１〜８のアルキル基、ｐ−トルイル基、フェニル基、カンホリル基、トリフルオロメチル基又はノナフルオロブチル基を表す。）

(In the formula, R ^B4 represents a hydrogen atom or a methyl group, and R ^B5 represents an alkyl group having 1 to 8 carbon atoms, a p-toluyl group, a phenyl group, a camphoryl group, a trifluoromethyl group, or a nonafluorobutyl group. )

R ^B4 in the formula (B-1) is preferably a methyl group.
The alkyl group having 1 to 8 carbon atoms and nonafluorobutyl group in R ^B5 of the formula (B-1) may be linear or branched.
Moreover, it is preferable that carbon number of the alkyl group in said ^RB5 is 1-4, and it is more preferable that it is 1-3.
Further, the bonding position between the camphoryl group and the sulfur atom in R ^B5 is not particularly limited, but is preferably the 10th position. That is, the camphoryl group is preferably a 10-camphoryl group.
R ^B5 in the formula (B-1) is preferably a methyl group, an n-propyl group, an n-octyl group, a p-toluyl group or a camphoryl group, and an n-propyl group, an n-octyl group, a p-toluyl group or It is more preferably a camphoryl group, and further preferably an n-propyl group or a p-toluyl group.
Details of these can be referred to the description of 0062 to 0066 of JP-A-2010-282178.

In formula (2-2), R ^4A represents a halogen atom, a hydroxyl group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a nitro group, and L represents an integer of 0 to 5. Represent. R ^3A is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogenated alkoxy group having 1 to 5 carbon atoms, or W A phenyl group which may be substituted, a naphthyl group which may be substituted with W, or an anthranyl group which may be substituted with W; 10 represents an alkyl group, an alkoxy group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, or a halogenated alkoxy group having 1 to 5 carbon atoms.

R ^3A in the formula (2-2) is methyl group, ethyl group, n-propyl group, n-butyl group, n-octyl group, trifluoromethyl group, pentafluoroethyl group, perfluoro-n-propyl group. Perfluoro-n-butyl group, p-tolyl group, 4-chlorophenyl group or pentafluorophenyl group is preferable, and may be methyl group, ethyl group, n-propyl group, n-butyl group or p-tolyl group. Particularly preferred.
The halogen atom represented by R ^4A is preferably a fluorine atom, a chlorine atom or a bromine atom.
The alkyl group having 1 to 4 carbon atoms represented by R ^4A is preferably a methyl group or an ethyl group.
The alkoxy group having 1 to 4 carbon atoms represented by R ^4A is preferably a methoxy group or an ethoxy group.
As L, 0-2 are preferable, and 0-1 are particularly preferable.

Among the compounds represented by the formula (2), as a preferred embodiment of the compound included in the compound represented by the formula (2-2), in the formula (2), R ^1A is a phenyl group or 4-methoxy. This is an embodiment in which a phenyl group is represented, R ^2A represents a cyano group, and R ^3A represents a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or a 4-tolyl group.

  Hereinafter, among the compounds represented by the formula (2), particularly preferred examples of the compounds included in the compound represented by the formula (2-2) are shown, but the present invention is not limited thereto.

α- (Methylsulfonyloxyimino) benzyl cyanide (R ^1A = phenyl group, R ^2A = cyano group, R ^3A = methyl group)
α- (ethylsulfonyloxyimino) benzylcyanide (R ^1A = phenyl group, R ^2A = cyano group, R ^3A = ethyl group)
α- (n-propylsulfonyloxyimino) benzyl cyanide (R ^1A = phenyl group, R ^2A = cyano group, R ^3A = n-propyl group)
α- (n-butylsulfonyloxyimino) benzyl cyanide (R ^1A = phenyl group, R ^2A = cyano group, R ^3A = n-butyl group)
α- (4-Toluenesulfonyloxyimino) benzyl cyanide (R ^1A = phenyl group, R ^2A = cyano group, R ^3A = 4-tolyl group)
α-[(Methylsulfonyloxyimino) -4-methoxyphenyl] acetonitrile (R ^1A = 4-methoxyphenyl group, R ^2A = cyano group, R ^3A = methyl group)
α-[(Ethylsulfonyloxyimino) -4-methoxyphenyl] acetonitrile (R ^1A = 4-methoxyphenyl group, R ^2A = cyano group, R ^3A = ethyl group)
α-[(n-propylsulfonyloxyimino) -4-methoxyphenyl] acetonitrile (R ^1A = 4-methoxyphenyl group, R ^2A = cyano group, R ^3A = n-propyl group)
α-[(n-butylsulfonyloxyimino) -4-methoxyphenyl] acetonitrile (R ^1A = 4-methoxyphenyl group, R ^2A = cyano group, R ^3A = n-butyl group)
α-[(4-Toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile (R ^1A = 4-methoxyphenyl group, R ^2A = cyano group, R ^3A = 4-tolyl group)

  In the positive photosensitive resin composition of the present invention, a photoacid generator represented by formula (1) or formula (2) can also be used.

（式中、Ｒ⁵、Ｒ⁶およびＲ⁷はそれぞれ独立に、置換基を有していてもよい、アルキル基または芳香族基を表し、アルキル基の場合、互いに連結し環を形成してもよく、Ｒ⁸およびＲ⁹はそれぞれ独立に、置換基を有していてもよい芳香族基を表し、Ｘ^-はＢＹ₄ ^-、ＰＹ₆ ^-、ＡｓＹ₆ ^-、ＳｂＹ₆ ^-、または、式（３）若しくは式（４）で表される一価のアニオンを表し、Ｙはそれぞれ独立に、ハロゲン原子を表す。）

(In the formula, R ⁵ , R ⁶ and R ⁷ each independently represents an alkyl group or an aromatic group which may have a substituent, and in the case of an alkyl group, they may be linked to each other to form a ring. R ⁸ and R ⁹ each independently represents an optionally substituted aromatic group, and X ⁻ represents BY ₄ ⁻ , PY ₆ ⁻ , AsY ₆ ⁻ , SbY ₆ ⁻ , or the formula ( 3) represents a monovalent anion represented by the formula (4), and each Y independently represents a halogen atom.)

（式中、Ｒ²¹、Ｒ²²およびＲ²³はそれぞれ独立に、炭素原子数１〜１０のアルキル基、炭素原子数１〜１０のフッ素原子を有するアルキル基、または、Ｒ²¹とＲ²²とが互いに炭素原子数２〜６のアルキレン基若しくは炭素原子数２〜６のフッ素原子を有するアルキレン基で結合した環を表す。）

(Wherein R ²¹ , R ²² and R ²³ are each independently an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or R ²¹ and R ²² are And represents a ring bonded to each other by an alkylene group having 2 to 6 carbon atoms or an alkylene group having 2 to 6 carbon atoms.

In formula (1), the alkyl group in R ⁵ , R ⁶ and R ⁷ is preferably an alkyl group having 1 to 10 carbon atoms, such as a methyl group, an ethyl group, or a tertiary butyl group (tert-butyl group). More preferred. In the formula (1), when two or more of R ⁵ , R ⁶ and R ⁷ are alkyl groups, it is preferable that the two or more alkyl groups are connected to each other to form a ring, As such a ring form, in the form containing a sulfur atom, a 5-membered ring (thiacyclopentane) and a 6-membered ring (thiacyclohexane) are more preferable, and a 5-membered ring is more preferable.
The aromatic group for R ⁵ , R ⁶ and R ⁷ is preferably an aromatic group having 6 to 30 carbon atoms and may have a substituent. Such aromatic groups include phenyl, naphthyl, 4-methoxyphenyl, 4-chlorophenyl, 4-methylphenyl, 4-tertiarybutylphenyl, 4-phenylthiophenyl, 2,4 , 6-trimethylphenyl group, 4-methoxy-1-naphthyl group, and 4- (4′-diphenylsulfoniophenylthio) phenyl group.
In the formula (2), preferred examples of the aromatic group in R ⁸ and R ⁹ are the same as the examples of R ⁵ , R ⁶ and R ⁷ .
As the substituent in R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ , an aromatic group is particularly preferable. Specifically, a phenyl group, a 4-methoxyphenyl group, a 4-chlorophenyl group, 4- (4 ′ A -diphenylsulfoniophenylthio) phenyl group is particularly preferred.
Moreover, the acid generator represented by Formula (1) or Formula (2) may couple | bond together by either R < ⁵ > -R < ⁹ >, and may form multimers, such as a dimer. For example, the 4- (4′-diphenylsulfoniophenylthio) phenyl group is an example of a dimer, and the counter anion in the 4- (4′-diphenylsulfoniophenylthio) phenyl group is BY ₄ ⁻ , PY ₆ ⁻ , AsY ₆ ⁻ , SbY ₆ ⁻ , or a monovalent anion represented by formula (3) or formula (4) is preferable.

In formulas (1) and (2), Y in BY ₄ ⁻ , PY ₆ ⁻ , AsY ₆ ⁻ and SbY ₆ ⁻ in X ⁻ is preferably a fluorine atom or a chlorine atom, and fluorine in terms of anion stability. Atoms are particularly preferred.
In formula (3) and formula (4), examples of the alkyl group having 1 to 10 carbon atoms in R ²¹ , R ²² and R ²³ include a methyl group, an ethyl group, a butyl group, a tertiary butyl group, and a cyclohexyl group. And octyl group. Examples of the alkyl group having a fluorine atom having 1 to 10 carbon atoms include a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, a dodecafluoropentyl group, and a perfluorooctyl group. Can be mentioned. Among these, R ²¹ , R ²² and R ²³ are preferably alkyl groups having 1 to 10 carbon atoms, more preferably alkyl groups having 1 to 6 carbon atoms, and 1 carbon atom. Alkyl groups having 4 to 4 fluorine atoms are particularly preferred in terms of sensitivity.
In formulas (3) and (4), when R ²¹ and R ²² are bonded to each other to form a ring, the alkylene group having 2 to 6 carbon atoms may be ethylene, propylene, butylene, or pentylene. Group, hexylene group and the like. Examples of the alkylene group containing a fluorine atom having 2 to 6 carbon atoms include a tetrafluoroethylene group, a hexafluoropropylene group, an octafluorobutylene group, a decafluoropentylene group, and a dodecafluorohexylene group. it can. Among these, when R ²¹ and R ²² are bonded to each other to form a ring, they are preferably bonded with an alkylene group having 2 to 6 carbon atoms, and a fluorine atom having 2 to 4 carbon atoms. It is more preferable to bond with an alkylene group having a hydrogen atom, and bonding with an alkylene group having 3 fluorine atoms is particularly preferable in terms of sensitivity.
In Formula (3) and Formula (4), R ²¹ and R ²² are a ring in which they are bonded to each other by an alkylene group having 2 to 6 carbon atoms or an alkylene group having 2 to 6 carbon atoms. Preferably there is.
In Formula (1) and Formula (2), X ⁻ is preferably BY ₄ ⁻ , PY ₆ ⁻ , or a monovalent anion represented by Formula (3) or Formula (4). It is particularly preferable in terms of sensitivity that it is a monovalent anion represented by (3).

  Moreover, as an acid generator represented by Formula (1), the acid generator represented by following formula (5) can also be used.

（式中、Ｒ¹⁰、Ｒ¹¹、Ｒ¹²およびＲ¹³はそれぞれ独立に、置換基を有していてもよい、アルキル基または芳香族基を表し、Ａｒ³およびＡｒ⁴はそれぞれ独立に、置換基を有していてもよい二価の芳香族基を表し、Ｘ^1-およびＸ^2-はそれぞれ独立に、ＢＹ₄ ^-、ＰＹ₆ ^-、ＡｓＹ₆ ^-、ＳｂＹ₆ ^-、または、前記式（３）若しくは前記式（４）で表される一価のアニオンを表し、Ｙはそれぞれ独立に、ハロゲン原子を表す。）

(In the formula, R ¹⁰ , R ¹¹ , R ¹² and R ¹³ each independently represents an alkyl group or an aromatic group which may have a substituent, and Ar ³ and Ar ⁴ are each independently substituted. X ¹⁻ and X ²⁻ each independently represents BY ₄ ⁻ , PY ₆ ⁻ , AsY ₆ ⁻ , SbY ₆ ⁻ , or the above formula ( 3) or a monovalent anion represented by the formula (4), and each Y independently represents a halogen atom.)

Preferred embodiments of the alkyl group and aromatic group in R ¹⁰ , R ¹¹ , R ¹² and R ¹³ of formula (5) are preferred for the alkyl group and aromatic group in R ⁵ , R ⁶ and R ⁷ of formula (1). This is the same as the embodiment.
The divalent aromatic group in Ar ³ and Ar ⁴ in the formula (5) is preferably a phenylene group or a naphthylene group, and particularly preferably a phenylene group.
Examples of the compound represented by formula (1) or formula (2) are given below. Among these, PAG-7, PAG-12, and PAG-14 are preferable, and PAG-12 is particularly preferable.

  In addition to the above, the compounds described in paragraphs 0036 to 0042 of JP-A-2007-279585 can also be preferably used as the acid generator of the present invention.

The photosensitive resin composition of the present invention preferably contains no 1,2-quinonediazide compound as the photoacid generator (B) that is sensitive to actinic rays. The reason is that the 1,2-quinonediazide compound generates a carboxy group by a sequential photochemical reaction, but its quantum yield is 1 or less and is less sensitive than the oxime sulfonate compound.
On the other hand, the oxime sulfonate compound acts as a catalyst for the deprotection of the acidic group protected in response to the actinic ray, so that the acid generated by the action of one photon Contributing to the deprotection reaction, the quantum yield exceeds 1, for example, a large value such as a power of 10, and it is assumed that high sensitivity is obtained as a result of so-called chemical amplification.

  In the photosensitive resin composition of the present invention, (B) the photoacid generator is preferably used in an amount of 0.1 to 15 parts by weight, and 0.1 to 10 parts by weight, based on 100 parts by weight of the polymer A. It is more preferable to use 0.5 to 6 parts by weight.

(C) Solvent The photosensitive resin composition of the present invention may contain (C) a solvent.
The photosensitive resin composition of the present invention is prepared as a solution in which the polymer A and the component B, which are essential components, and optional components of various additives described below which are preferable components are dissolved in a solvent (C). Is preferred.
As the solvent (C) used in the photosensitive resin composition of the present invention, known solvents can be used, such as ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers, ethylene glycol monoalkyl ether acetates, propylene. Glycol monoalkyl ethers, propylene glycol dialkyl ethers, propylene glycol monoalkyl ether acetates, diethylene glycol dialkyl ethers, diethylene glycol monoalkyl ether acetates, dipropylene glycol monoalkyl ethers, dipropylene glycol dialkyl ethers, dipropylene glycol Examples include monoalkyl ether acetates, esters, ketones, amides, lactones and the like.

  Examples of the (Component C) solvent used in the photosensitive resin composition of the present invention include (1) ethylene glycol such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and ethylene glycol monobutyl ether. Monoalkyl ethers; (2) ethylene glycol dialkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether; (3) ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl Ethylene glycol monoalkyl ethers such as ether acetate and ethylene glycol monobutyl ether acetate (4) Propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether; (5) propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol Propylene glycol dialkyl ethers such as monomethyl ether and diethylene glycol monoethyl ether;

  (6) Propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate; (7) diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl Diethylene glycol dialkyl ethers such as methyl ether; (8) diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monobutyl ether acetate, etc. (9) Dipropylene glycol monoalkyl ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether; (10) Dipropylene glycol dimethyl ether Dipropylene glycol dialkyl ethers such as dipropylene glycol diethyl ether and dipropylene glycol ethyl methyl ether;

  (11) Dipropylene glycol monoalkyl ether acetates such as dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monopropyl ether acetate, dipropylene glycol monobutyl ether acetate; (12) methyl lactate, lactic acid Lactic acid esters such as ethyl, n-propyl lactate, isopropyl lactate, n-butyl lactate, isobutyl lactate, n-amyl lactate, isoamyl lactate; (13) n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, N-hexyl acetate, 2-ethylhexyl acetate, ethyl propionate, n-propyl propionate, isopropyl propionate, n-butyl propionate, isobutyl propionate, methyl butyrate , Ethyl butyrate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, n-butyl butyrate, isobutyl butyrate and the like; (14) ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, Ethyl 2-hydroxy-3-methylbutyrate, ethyl methoxyacetate, ethyl ethoxyacetate, 3-methoxypropionmethyl, 3-methoxypropionethyl, 3-ethoxypropionmethyl, 3-ethoxypropionethyl, 3-methoxybutylacetate, 3- Others such as methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate Esters;

  (15) ketones such as methyl ethyl ketone, methyl propyl ketone, methyl-n-butyl ketone, methyl isobutyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone; (16) N-methylformamide, N, N-dimethyl Examples include amides such as formamide, N-methylacetamide, N, N-dimethylacetamide, and N-methylpyrrolidone; and (17) lactones such as γ-butyrolactone.

In addition, benzyl ethyl ether, dihexyl ether, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonal as necessary for these solvents , Benzyl alcohol, anisole, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, ethylene carbonate, propylene carbonate and the like can also be added.
Of the above-mentioned solvents, diethylene glycol ethyl methyl ether and / or propylene glycol monomethyl ether acetate are preferable, and propylene glycol monomethyl ether acetate is particularly preferable.
These solvents can be used alone or in combination of two or more.

  The content of the solvent (C) in the photosensitive resin composition of the present invention is preferably 50 to 3,000 parts by weight and more preferably 100 to 2,000 parts by weight per 100 parts by weight of the polymer A. Preferably, it is 150-1500 weight part.

(D) Thermal crosslinking agent It is preferable that the photosensitive resin composition of this invention contains (D) thermal crosslinking agent as needed. (Component D) The heat flow in a baking process can be suppressed by adding a thermal crosslinking agent. In the present invention, (D) is other than the polymer A.
Preferred examples of the thermal crosslinking agent include an alkoxymethyl group-containing crosslinking agent, an epoxy resin having an epoxy group, a (meth) acrylic resin having a carboxy group, which will be described later.
An alkoxymethyl group-containing crosslinking agent can also be suitably used, and preferably contains at least a methylolated melamine compound.

  The content of the component (E) in the photosensitive resin composition of the present invention is preferably 0.5 to 50 parts by weight and more preferably 1 to 40 parts by weight with respect to 100 parts by weight of the polymer A. Preferably, the amount is 5 to 30 parts by weight. Within the above range, it is easy to obtain a rectangle or a profile close to a rectangle.

<Alkoxymethyl group-containing crosslinking agent>
As the alkoxymethyl group-containing crosslinking agent, alkoxymethylated melamine, alkoxymethylated benzoguanamine, alkoxymethylated glycoluril, alkoxymethylated urea and the like are preferable. These can be obtained by converting the methylol group of methylolated melamine, methylolated benzoguanamine, methylolated glycoluril, or methylolated urea to an alkoxymethyl group, respectively. The type of the alkoxymethyl group is not particularly limited, and examples thereof include a methoxymethyl group, an ethoxymethyl group, a propoxymethyl group, and a butoxymethyl group. From the viewpoint of outgas generation amount, A methyl group is particularly preferred.
Among these crosslinkable compounds, alkoxymethylated melamine, alkoxymethylated benzoguanamine, and alkoxymethylated glycoluril are mentioned as preferable crosslinkable compounds, and alkoxymethylated glycoluril is particularly preferable from the viewpoint of transparency.

  These alkoxymethyl group-containing crosslinking agents are available as commercial products. For example, Cymel 300, 301, 303, 370, 325, 327, 701, 266, 267, 238, 1141, 272, 202, 1156, 1158, 1123, 1170, 1174, UFR65, 300 (above, manufactured by Mitsui Cyanamid Co., Ltd.), Nicarax MX-750, -032, -706, -708, -40, -31, -270, -280, -290, Nicarac MS-11, Nicarak MW-30HM, -100LM, -390, (manufactured by Sanwa Chemical Co., Ltd.) and the like can be preferably used. Among these, Nicalac MX-270 and Nicalac MW-100LM are particularly preferable.

  When the alkoxymethyl group-containing crosslinking agent is used in the photosensitive resin composition of the present invention, the addition amount of the alkoxymethyl group-containing crosslinking agent is 0.05 to 50 parts by weight with respect to 100 parts by weight of the polymer A. Preferably, it is 0.5-10 weight part, More preferably, it is 0.5-5 weight part. By adding in this range, high sensitivity and preferable alkali solubility during development can be obtained.

(E) Compound having epoxy group, oxetanyl group, hydroxyl group and carboxy group The photosensitive resin composition of the present invention suppresses the curing shrinkage of the film and obtains a rectangular profile after baking. Therefore, the epoxy group, oxetanyl group, hydroxyl group It is also effective to add a compound having a carboxy group.
(E) is preferably a resin having a weight average molecular weight of 1,000 or more.
Specific examples include a copolymer containing a repeating unit containing an epoxy group, an oxetanyl group, a hydroxyl group and / or a carboxy group.
Moreover, the compound which does not contain the said functional group at all like the homopolymer of polymethylmethacrylate (PMMA) can also be added as a component (E).
In addition, in this invention, when (E) satisfy | fills the definition of the said crosslinking agent, it classify | categorizes into both. For example, when (E) is an epoxy resin, the epoxy resin is (D) a crosslinking agent and is (E). The component (E) in the present invention is other than the polymer A.
Moreover, there is no restriction | limiting in particular as a measuring method of an epoxy equivalent, an oxetanyl equivalent, a hydroxyl group equivalent, and a carboxy group equivalent, For example, it can titrate content of the said group in a specific amount of compounds, etc. It can be calculated by measuring according to For example, it can be measured with reference to the method described in JIS K7236, K0070, etc.

<Epoxy resin>
As a component (E), an epoxy resin is mentioned preferably. By adding an epoxy resin, the heat flow at the time of baking can be suppressed. Further, the epoxy resin preferably has a large epoxy equivalent in order to obtain a rectangular shape or a profile close to a rectangular shape by suppressing curing shrinkage of the crosslinked film. Specifically, 400 g / eq or more is preferable, 400 to 1,000 g / eq is more preferable, and 400 to 600 g / eq is particularly preferable. Within the above range, since the curing shrinkage is small, a rectangular shape or a profile close to a rectangular shape can be obtained, and the allowable range of the process conditions for producing the cured film is large.
In addition, it is preferable that the measuring method of epoxy equivalent conforms to JIS K7236.

As an epoxy resin, what is marketed and what was synthesize | combined arbitrarily can be used. Specific examples of commercially available epoxy resins are shown below.
EPICLON 1050, 1055, 3050, 4050, 7050, AM-020-P, AM-040-P, HM-091, HM-101, 1050-70X, 1050-75X, 1055-75X, 1051-75M, 7070-40K HM-091-40AX, 152, 153, 153-60T, 153-60M, 1121N-80M, 1123P-75M, TSR-601, 1650-75MPX, 5500, 5800, 5300-70, 5500-60, EXA-4850 -150, EXA-4850-1000, EXA-4816, EXA-4822 (manufactured by DIC Corporation),
Epoxy resins 1001, 1002, 1003, 1055, 1004, 1004AF, 1007, 1009, 1010, 1003F, 1004F, 1005F, 1009F, 1004FS, 1006FS, 1007FS, 1001B80, 1001X70, 1001X75, 1001T75, 4004P, 4005P, 4007P, 4010P 1256, 4250, 4275, 5046B80, 5047B75, 5050T60, 5050, 5051, 871, 872, 872X75 (manufactured by Mitsubishi Chemical Corporation),
YD-011, YD-012, YD-013, YD-014, YD-017, YD-019, YD-020G, YD-7011R, YD-901, YD-902, YD-903N, YD-904, YD- 907, YD-6020, YDF-2001, YDF-2004, YDF-2005RL, YDB-400, YDB-405, YDB-400T60, YDB-400EK60, YDB-500EK80, FX-305EK70, ERF-001M30 (above, New Day Sakai Chemical Co., Ltd.).

  The structure of the epoxy resin preferably has a BPA (bisphenol A) skeleton, specifically, EPICLON 1050, 1055, 3050, 4050, EXA-4850-150, EXA-4850-1000, EXA-4816, EXA. -4822 (above, manufactured by DIC Corporation), epoxy resins 1001, 1002, 1003, 1055, 1004, 1004AF (above, manufactured by Mitsubishi Chemical Corporation), YD-011, YD-012, YD-013, YD- 014 (manufactured by Nippon Steel Chemical Co., Ltd.).

  The addition amount of the epoxy resin is preferably 10 to 50% by weight, particularly preferably 20 to 40% by weight or more based on the total solid content of the photosensitive resin composition. Within the above range, it is easy to obtain a rectangle or a profile close to a rectangle and to form a desired pattern by a development process.

The molecular weight (weight average molecular weight) of the epoxy resin is preferably 500 or more. When the molecular weight is 500 or less, volatilization in the solvent drying step or outflow in the development step can be suppressed, and the effect of adding the epoxy resin can be sufficiently obtained.
An epoxy resin can also be used individually by 1 type, and 2 or more types can also be mixed and used for it.
Moreover, it is preferable that the photosensitive resin composition of this invention contains the alkoxymethyl group containing crosslinking agent and an epoxy resin from a viewpoint of obtaining the profile nearer rectangular.

<(Meth) acrylic resin having carboxy group>
As a component (E), the (meth) acrylic resin which has a carboxy group is mentioned.
As the (meth) acrylic resin having a carboxy group, one having a large carboxy group equivalent is preferable in order to obtain a rectangular profile by suppressing curing shrinkage of the crosslinked film. Specifically, 400 g / eq or more is preferable, 400 to 1,000 g / eq is more preferable, and 400 to 600 g / eq is particularly preferable.
The (meth) acrylic resin having a carboxy group can be obtained by using a known (meth) acrylic monomer, and adjusting the carboxy group equivalent by adjusting the type and amount ratio of the monomer.
As the acrylic monomer, for example, unsaturated monocarboxylic acid, (meth) acrylic acid esters, and crotonic acid esters (meth) acrylamides are preferable.
Specific examples of such a monomer include the following compounds.
Examples of the unsaturated monocarboxylic acid include (meth) acrylic acid, crotonic acid, α-chloroacrylic acid, and cinnamic acid.

  Examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, acetoxyethyl (meth) acrylate, phenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (Meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (2-methoxyethoxy) ethyl (meth) acrylate , Cyclohexyl (meth) acrylate, benzyl (meth) acrylate, diethylene glycol monomethyl ether (meth) acrylate, diethylene glycol monoethyl ether (meth) acrylate, diethylene glycol monophenyl ether (meth) acrylate, triethylene glycol monomethyl ether (meth) acrylate, tri Ethylene glycol monoethyl ether (meth) acrylate, dipropylene glycol monomethyl ether (meth) acrylate, polyethylene glycol monomethyl ether (meth) acrylate, polypropylene glycol monomethyl ether (meth) acrylate, monomethyl copolymer of ethylene glycol and propylene glycol Ether (meth) acrylate, N, N- Methylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate.

Examples of the crotonic acid esters include butyl crotonic acid and hexyl crotonic acid.
(Meth) acrylamides include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, Nn-butylacryl (meth) amide, N- tertbutyl (meth) acrylamide, N-cyclohexyl (meth) acrylamide, N- (2-methoxyethyl) (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N- Examples include phenyl (meth) acrylamide, N-benzyl (meth) acrylamide, (meth) acryloylmorpholine, and the like.
Among these, the (meth) acrylic resin having a carboxy group is preferably a copolymer of benzyl (meth) acrylate and (meth) acrylic acid.

<Other ingredients>
The photosensitive resin composition of the present invention may contain other components other than the polymer A to the component E.
As another component, it is preferable to contain the (component F) sensitizer from a sensitivity viewpoint. From the viewpoint of sensitivity, it is preferable to add (Component G) a development accelerator.
Furthermore, the photosensitive resin composition of the present invention preferably contains (Component H) an adhesion improver from the viewpoint of substrate adhesion, and contains (Component I) a basic compound from the viewpoint of liquid storage stability. From the viewpoint of applicability, it is preferable to contain (Component J) a surfactant (such as a fluorine-based surfactant or a silicone-based surfactant).
Furthermore, if necessary, the photosensitive resin composition of the present invention includes (Component K) an antioxidant, (Component L) a plasticizer, (Component M) a thermal radical generator, and (Component N) a thermal acid. Known additives such as generators, (component O) acid proliferating agents, ultraviolet absorbers, thickeners, and organic or inorganic suspending agents can be added.
In addition, the photosensitive resin composition of the present invention has a methylol cross-linking agent, an epoxy resin, (Component H) an adhesion improver, (Component I) a basic compound, and (Component J) from the viewpoint of obtaining a more rectangular profile. ) A surfactant is preferably contained, and an alkoxymethyl group-containing crosslinking agent, an epoxy resin, (Component H) an adhesion improver, (Component I) a basic compound, and (Component J) a surfactant. Is particularly preferred.
Hereinafter, other components that can be included in the photosensitive resin composition of the present invention will be described.

(Component F) Sensitizer In the photosensitive resin composition of the present invention, in the combination with the above-mentioned (Component B) photoacid generator, (Component F) a sensitizer is added to promote the decomposition thereof. Is preferred. The sensitizer absorbs actinic rays or radiation and enters an electronically excited state. The sensitizer in an electronically excited state comes into contact with the photoacid generator, and effects such as electron transfer, energy transfer, and heat generation occur. Thereby, a photo-acid generator raise | generates a chemical change and decomposes | disassembles and produces | generates an acid.
As examples of preferable sensitizers, those described in paragraph numbers 0162 to 0168 of JP 2011-074314 A can be preferably used.

A commercially available sensitizer may be used, or it may be synthesized by a known synthesis method.
The addition amount of the sensitizer is preferably 20 to 300 parts by weight, particularly preferably 30 to 200 parts by weight, with respect to 100 parts by weight of (Component B) the photoacid generator, from the viewpoint of both sensitivity and transparency.

(Component G) Development accelerator The photosensitive resin composition of the present invention preferably contains (Component G) a development accelerator.
(Component G) As the development accelerator, any compound having a development acceleration effect can be used, but a compound having at least one structure selected from the group consisting of a carboxy group, a phenolic hydroxyl group, and an alkyleneoxy group The compound having a carboxy group or a phenolic hydroxyl group is more preferable, and the compound having a phenolic hydroxyl group is most preferable.
Further, the molecular weight of the (component G) development accelerator is preferably 100 to 2,000, more preferably 150 to 1,500, and particularly preferably 150 to 1,000.

Examples of development accelerators having an alkyleneoxy group include polyethylene glycol, polyethylene glycol monomethyl ether, polyethylene glycol dimethyl ether, polyethylene glycol glyceryl ester, polypropylene glycol glyceryl ester, polypropylene glycol diglyceryl ester, polybutylene glycol, Examples thereof include polyethylene glycol-bisphenol A ether, polypropylene glycol-bisphenol A ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, and compounds described in JP-A-9-222724.
Examples of compounds having a carboxy group include compounds described in JP-A 2000-66406, JP-A 9-6001, JP-A 10-20501, JP-A 11-338150, and the like.
Examples of those having a phenolic hydroxyl group include JP-A No. 2005-346024, JP-A No. 10-133366, JP-A No. 9-194415, JP-A No. 9-222724, JP-A No. 11-171810, Examples thereof include compounds described in JP 2007-121766, JP-A-9-297396, JP-A 2003-43679, and the like. Among these, a phenol compound having 2 to 10 benzene rings is preferable, and a phenol compound having 2 to 5 benzene rings is more preferable. Particularly preferred is a phenolic compound disclosed as a dissolution accelerator in JP-A-10-133366.

(Component G) One type of development accelerator may be used alone, or two or more types may be used in combination.
The addition amount of (Component G) development accelerator in the photosensitive resin composition of the present invention is preferably 0.1 to 30 parts by weight with respect to 100 parts by weight of the polymer A from the viewpoint of sensitivity and residual film ratio. 2 to 20 parts by weight is more preferable, and 0.5 to 10 parts by weight is most preferable.

(Component H) Adhesion Improving Agent The photosensitive resin composition of the present invention preferably contains (Component H) an adhesion improving agent.
The (component H) adhesion improver that can be used in the photosensitive resin composition of the present invention is an inorganic substance that serves as a substrate, for example, a silicon compound such as silicon, silicon oxide, or silicon nitride, or a metal such as gold, copper, or aluminum. It is a compound that improves adhesion to an insulating film. Specific examples include silane coupling agents and thiol compounds. The silane coupling agent as the (component H) adhesion improver used in the present invention is for the purpose of modifying the interface, and any known silane coupling agent can be used without any particular limitation.

Preferred silane coupling agents include, for example, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltriacoxysilane, γ-glycidoxypropylalkyldialkoxysilane, γ- Methacryloxypropyltrialkoxysilane, γ-methacryloxypropylalkyldialkoxysilane, γ-chloropropyltrialkoxysilane, γ-mercaptopropyltrialkoxysilane, β- (3,4-epoxycyclohexyl) ethyltrialkoxysilane, vinyltri An alkoxysilane is mentioned.
Of these, γ-glycidoxypropyltrialkoxysilane and γ-methacryloxypropyltrialkoxysilane are more preferable, and γ-glycidoxypropyltrialkoxysilane is more preferable.

These can be used alone or in combination of two or more. These are effective in improving the adhesion to the substrate and are also effective in adjusting the taper angle with the substrate.
The content of the (component H) adhesion improver in the photosensitive resin composition of the present invention is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the polymer A. .

(Component I) Basic Compound The photosensitive resin composition of the present invention preferably contains (Component I) a basic compound.
(Component I) The basic compound can be arbitrarily selected from those used in chemically amplified resists. Examples thereof include aliphatic amines, aromatic amines, heterocyclic amines, quaternary ammonium hydroxides, and quaternary ammonium salts of carboxylic acids.

Examples of the aliphatic amine include trimethylamine, diethylamine, triethylamine, di-n-propylamine, tri-n-propylamine, di-n-pentylamine, tri-n-pentylamine, diethanolamine, triethanolamine, and dicyclohexylamine. , Dicyclohexylmethylamine and the like.
Examples of the aromatic amine include aniline, benzylamine, N, N-dimethylaniline, diphenylamine and the like.
Examples of the heterocyclic amine include pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, N-methyl-4-phenylpyridine, 4-dimethylaminopyridine, imidazole, benzimidazole, 4-methylimidazole, 2-phenylbenzimidazole, 2,4,5-triphenylimidazole, nicotine, nicotinic acid, nicotinamide, quinoline, 8-oxyquinoline, pyrazine, Pyrazole, pyridazine, purine, pyrrolidine, piperidine, piperazine, morpholine, 4-methylmorpholine, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.3.0] -7 -Undecene and the like.
Examples of the quaternary ammonium hydroxide include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide, and tetra-n-hexylammonium hydroxide.
Examples of the quaternary ammonium salt of carboxylic acid include tetramethylammonium acetate, tetramethylammonium benzoate, tetra-n-butylammonium acetate, and tetra-n-butylammonium benzoate.

The basic compounds that can be used in the present invention may be used singly or in combination of two or more. However, it is preferable to use two or more in combination, and it is more preferable to use two in combination. It is preferable to use two kinds of heterocyclic amines in combination.
The content of the (Component I) basic compound in the photosensitive resin composition of the present invention is preferably 0.001 to 1 part by weight with respect to 100 parts by weight of the polymer A, and 0.002 to 0.2. More preferred are parts by weight.

(Component J) Surfactant (fluorine surfactant, silicone surfactant, etc.)
The photosensitive resin composition of the present invention preferably contains (Component J) a surfactant (such as a fluorine-based surfactant or a silicone-based surfactant).
As a surfactant, a copolymer (3) containing the structural unit A and the structural unit B shown below can be given as a preferred example. The weight average molecular weight (Mw) of the copolymer is preferably 1,000 to 10,000, more preferably 1,500 to 5,000. The weight average molecular weight is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

In the copolymer (3), R ²¹ and R ²³ each independently represent a hydrogen atom or a methyl group, R ²² represents a linear alkylene group having 1 to 4 carbon atoms, and R ²⁴ represents a hydrogen atom or carbon number. 1 represents an alkyl group having 1 to 4 carbon atoms, L represents an alkylene group having 3 to 6 carbon atoms, p and q are weight percentages representing a polymerization ratio, and p is a numerical value of 10% to 80% by weight. Q represents a numerical value of 20% by weight to 90% by weight, r represents an integer of 1 to 18 and n represents an integer of 1 to 10.
L in the structural unit B is preferably an alkylene group represented by the following formula (4).

In the formula (4), R ²⁵ represents an alkyl group having 1 to 4 carbon atoms, and is preferably an alkyl group having 1 to 3 carbon atoms in terms of compatibility and wettability to the coated surface. More preferred is an alkyl group of 3.
The sum of p and q (p + q) is preferably p + q = 100, that is, 100% by weight.

  Specific examples of fluorine surfactants and silicone surfactants include JP-A Nos. 62-36663, 61-226746, 61-226745, and 62-170950. , JP-A-63-34540, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, JP-A-2001-330953, etc. An activator can be mentioned and a commercially available surfactant can also be used. Examples of commercially available surfactants that can be used include F-top EF301 and EF303 (above, manufactured by Mitsubishi Materials Electronic Chemical Co., Ltd.), Florard FC430, 431 (above, manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171 and F173. , F176, F189, R08 (above, manufactured by DIC Corporation), Surflon S-382, SC101, 102, 103, 104, 105, 106 (above, manufactured by Asahi Glass Co., Ltd.), PolyFox series (produced by OMNOVA), etc. Fluorine-based surfactant or silicone-based surfactant. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicone surfactant.

These surfactants can be used individually by 1 type or in mixture of 2 or more types. Moreover, you may use together a fluorine-type surfactant and a silicone type surfactant.
In the photosensitive resin composition of the present invention, the amount of (Component J) surfactant (fluorine-based surfactant, silicone-based surfactant, etc.) added is 10 parts by weight or less based on 100 parts by weight of the polymer A. It is preferably 0.01 to 10 parts by weight, more preferably 0.01 to 1 part by weight.

(Component K) Antioxidant The description of paragraph number 0086-0087 of Unexamined-Japanese-Patent No. 2011-170305 can be referred for the antioxidant used by this invention.

(Component L) Plasticizer The photosensitive resin composition of the present invention may contain (Component L) a plasticizer.
Examples of (Component L) plasticizer include dibutyl phthalate, dioctyl phthalate, didodecyl phthalate, polyethylene glycol, glycerin, dimethyl glycerin phthalate, dibutyl tartrate, dioctyl adipate, and triacetyl glycerin.
The content of the (component L) plasticizer in the photosensitive resin composition of the present invention is preferably 0.1 to 30 parts by weight with respect to 100 parts by weight of the polymer A, and 1 to 10 parts by weight. Is more preferable.

(Component M) Thermal radical generator The photosensitive resin composition of the present invention may contain (Component M) a thermal radical generator, and is a compound having at least one ethylenically unsaturated double bond as described above. When such an ethylenically unsaturated compound is contained, it is preferable to contain (Component M) a thermal radical generator. Details of the thermal radical generator can be referred to paragraph No. 0113 of JP2011-170305A.
(Component M) A thermal radical generator may be used alone or in combination of two or more.
The content of (Component M) the thermal radical generator in the photosensitive resin composition of the present invention is preferably 0.01 to 50 parts by weight when the polymer A is 100 parts by weight from the viewpoint of improving film properties. 0.1-20 weight part is more preferable, and it is most preferable that it is 0.5-10 weight part.

(Component N) Thermal acid generator In the present invention, (Component N) a thermal acid generator may be used in order to improve film physical properties and the like at low temperature curing.
The thermal acid generator is a compound that generates an acid by heat, and is usually a compound having a thermal decomposition point in the range of 130 ° C. to 250 ° C., preferably 150 ° C. to 220 ° C., for example, sulfonic acid, It is a compound that generates a low nucleophilic acid such as carboxylic acid or disulfonylimide.
As the generated acid, sulfonic acid, an alkylcarboxylic acid substituted with an electron withdrawing group or an arylcarboxylic acid having a strong pKa of 2 or less, and a disulfonylimide substituted with an electron withdrawing group are also preferred. Examples of the electron withdrawing group include a halogen atom such as a fluorine atom, a haloalkyl group such as a trifluoromethyl group, a nitro group, and a cyano group.

In the present invention, it is also preferable to use a sulfonic acid ester that does not substantially generate an acid by exposure to exposure light and generates an acid by heat.
The fact that acid is not substantially generated by exposure light exposure can be determined by no change in the spectrum by measuring IR spectrum and NMR spectrum before and after exposure of the compound.
The molecular weight of the thermal acid generator is preferably 230 to 1,000, more preferably 230 to 800.

As the sulfonic acid ester usable in the present invention, a commercially available one may be used, or one synthesized by a known method may be used. Sulfonic esters can be synthesized, for example, by reacting sulfonyl chloride or sulfonic anhydride with the corresponding polyhydric alcohol under basic conditions.
The content of the thermal acid generator in the photosensitive resin composition is preferably 0.5 to 20 parts by weight, particularly preferably 1 to 15 parts by weight, based on 100 parts by weight of the polymer A.

(Component O) Acid Proliferator The photosensitive resin composition of the present invention can use (Component O) an acid multiplier for the purpose of improving sensitivity. The acid proliferating agent used in the present invention is a compound that can further generate an acid by an acid-catalyzed reaction to increase the acid concentration in the reaction system, and is a compound that exists stably in the absence of an acid. In such a compound, since one or more acids increase in one reaction, the reaction proceeds at an accelerated rate as the reaction proceeds. However, the generated acid itself induces self-decomposition, and is generated here. The acid strength is preferably 3 or less as an acid dissociation constant, pKa, and particularly preferably 2 or less.
Specific examples of the acid proliferating agent include paragraphs 0203 to 0223 of JP-A-10-1508, paragraphs 0016 to 0055 of JP-A-10-282642, and page 39, line 12 of JP-A-9-512498. Examples of the compounds described in the first to page 47, line 2 are listed.

  Examples of the acid proliferating agent that can be used in the present invention include pKa such as dichloroacetic acid, trichloroacetic acid, methanesulfonic acid, benzenesulfonic acid, trifluoromethanesulfonic acid, and phenylphosphonic acid, which are decomposed by an acid generated from the acid generator. Examples include compounds that generate 3 or less acids.

  The content of the acid multiplier in the photosensitive resin composition is 10 to 1,000 parts by weight with respect to 100 parts by weight of (Component B) photoacid generator. From the viewpoint of contrast, it is preferably 20 to 500 parts by weight.

(Pattern preparation method)
The pattern production method of the present invention is not particularly limited as long as it is a method for producing a pattern using the photosensitive resin composition of the present invention, but the solvent is removed from the photosensitive resin composition of the present invention to form a film. A film forming step, an exposure step of exposing the film to a pattern with actinic rays, a developing step of developing the exposed film with an aqueous developer to form a pattern, and a baking step of heating the pattern It is preferable.
The pattern production method in the present invention more preferably includes the following steps (1) to (6).
(1) The process of apply | coating the photosensitive resin composition of this invention on a board | substrate (2) The process of removing a solvent from the apply | coated photosensitive resin composition (3) Activate the photosensitive resin composition from which the solvent was removed Step of exposing to pattern by light beam (4) Step of developing exposed photosensitive resin composition with aqueous developer (5) Step of exposing developed photosensitive resin composition with actinic ray (post exposure)
(6) Baking process of thermosetting developed photosensitive resin composition The film forming process is preferably the coating process and the solvent removing process.
Each step will be described below in order.

  (1) A desired dry coating film can be formed by applying the photosensitive resin composition of the present invention to a predetermined substrate and removing the solvent by reducing pressure and / or heating (pre-baking). Substrate materials that can be used in the present invention, silicon, silicon dioxide, silicon nitride, alumina, glass, glass-ceramics, gallium arsenide, indium phosphide, copper, aluminum, nickel, iron, steel, copper-silicon alloys, Indium-tin oxide coated glass; organic films such as polyimide and polyester; including, but not limited to, any substrate containing a patterned region of metal, semiconductor, and insulating material. Optionally, a baking step can be performed on the substrate to remove absorbed moisture before applying the photosensitive resin composition of the present invention. The coating method to a board | substrate is not specifically limited, For example, methods, such as a slit coat method, a spray method, a roll coat method, a spin coat method, can be used. In the case of a large substrate, the slit coat method is particularly preferable. Here, the large substrate means a substrate having a side of 1 m or more on each side.

In the solvent removal step (2), the solvent is removed from the applied film by vacuum (vacuum) and / or heating to form a dry coating film on the substrate. The heating condition is a range in which the acid-decomposable group is decomposed in the repeating unit (a1) in the polymer A in the unexposed area, and the polymer A is not soluble in the alkaline developer. Although it depends on the blending ratio, it is preferably about 70 to 120 ° C. for about 30 to 300 seconds.
The photosensitive resin composition of this invention is used suitably as what is called a thick film resist whose film thickness after drying is 4 micrometers or more. This is because the present invention has high sensitivity and good shape controllability. The film thickness is preferably 4 to 500 μm, particularly preferably 4 to 100 μm.

(3) In the exposure step, the substrate provided with the dry coating film is irradiated with an actinic ray having a predetermined pattern. Exposure may be performed through a mask, or a predetermined pattern may be drawn directly. Actinic rays having a wavelength of 300 nm to 450 nm can be preferably used. After the exposure step, PEB (post-exposure heat treatment) is performed as necessary.
For exposure with actinic light, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a chemical lamp, a laser generator, or the like can be used.
When a mercury lamp is used, actinic rays having wavelengths such as g-line (436 nm), i-line (365 nm), and h-line (405 nm) can be preferably used. Mercury lamps are preferred in that they are suitable for large area exposure compared to lasers.

When a laser is used, 343 nm and 355 nm are used for a solid (YAG) laser, 351 nm (XeF) is used for an excimer laser, and 375 nm and 405 nm are used for a semiconductor laser. Among these, 355 nm and 405 nm are more preferable from the viewpoint of stability and cost. The coating can be irradiated with the laser once or a plurality of times.
The energy density per pulse of the laser is preferably 0.1 mJ / cm ² or more and 10,000 mJ / cm ² or less. In order to sufficiently cure the coating film, 0.3 mJ / cm ² or more is more preferable, and 0.5 mJ / cm ² or more is most preferable. cm ² or less is more preferable, and 100 mJ / cm ² or less is most preferable. The pulse width is preferably 0.1 nsec or more and 30,000 nsec or less. In order not to decompose the color coating film due to the ablation phenomenon, 0.5 nsec or more is more preferable, and 1 nsec or more is most preferable, and in order to improve the alignment accuracy at the time of scanning exposure, 1,000 nsec or less is more preferable, Most preferred is 50 nsec or less.
Furthermore, the frequency of the laser is preferably 1 Hz or more and 50,000 Hz or less. In order to shorten the exposure processing time, 10 Hz or more is more preferable, and 100 Hz or more is most preferable. In order to improve the alignment accuracy at the time of scanning exposure, 10,000 Hz or less is more preferable, and 1,000 Hz or less is most preferable.
Compared with a mercury lamp, a laser is preferable in that the focus can be easily reduced and a mask for forming a pattern in the exposure process is not necessary and the cost can be reduced.
There are no particular restrictions on the exposure apparatus that can be used in the present invention. Commercially available exposure apparatuses include Callisto (manufactured by Buoy Technology), AEGIS (manufactured by Buoy Technology), and DF2200G (Dainippon). Screen Manufacturing Co., Ltd.) can be used. Further, devices other than those described above are also preferably used.
Moreover, irradiation light can also be adjusted through spectral filters, such as a long wavelength cut filter, a short wavelength cut filter, and a band pass filter, as needed.

In order to accelerate the decomposition reaction in the region where the acid catalyst is generated, PEB (post-exposure heat treatment) can be performed as necessary. PEB can promote the formation of a carboxy group from an acid-decomposable group.
Since the acid-decomposable group in the repeating unit (a1) in the present invention has low activation energy for acid decomposition and is easily decomposed by an acid derived from an acid generator by exposure to generate a carboxy group, PEB is necessarily performed. Alternatively, a positive image can be formed by development.
In addition, by performing PEB at a relatively low temperature, hydrolysis of an acid-decomposable group can be promoted without causing a crosslinking reaction. The temperature for performing PEB is preferably 30 ° C. or higher and 130 ° C. or lower, more preferably 40 ° C. or higher and 110 ° C. or lower, and particularly preferably 50 ° C. or higher and 90 ° C. or lower.

In the developing step (4), the polymer A having a liberated carboxy group is developed using an alkaline developer. A positive image is formed by removing an exposed area containing a resin composition having a carboxy group that is easily dissolved in an alkaline developer.
Examples of basic compounds that can be used in the alkaline developer include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; alkali metal carbonates such as sodium carbonate and potassium carbonate; sodium bicarbonate, Alkali metal bicarbonates such as potassium bicarbonate; ammonium hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline hydroxide; and aqueous solutions such as sodium silicate and sodium metasilicate can be used. An aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant to the alkaline aqueous solution can also be used as a developer.
The pH of the developer is preferably 10.0 to 14.0.
The development time is preferably 30 to 180 seconds, and the development method may be any of a liquid piling method, a dip method, a shower method, and the like. After the development, washing with running water is preferably performed for 10 to 90 seconds to form a desired pattern.

(5) A catalyst that promotes cross-linking by re-exposing (post) exposure to a pattern-formed substrate with actinic rays prior to heat treatment and generating an acid from (Component B) a photoacid generator present in an unexposed portion. It is preferable to function as.
That is, the method for forming a cured film in the present invention preferably includes a re-exposure step in which re-exposure is performed with actinic rays between the development step and the baking step.
The exposure in the re-exposure step may be performed by the same means as in the exposure step. In the re-exposure step, the entire surface of the substrate on which the film is formed by the photosensitive resin composition of the present invention is exposed. It is preferable. A preferable exposure amount in the re-exposure step is 100 to 1,000 mJ / cm ² .

In the baking step (6), the obtained positive image is heated to thermally decompose the acid-decomposable group in the repeating unit (a1) to form a carboxy group, which is crosslinked with an epoxy group and / or an oxetanyl group. Thus, a cured film can be formed.
In order to obtain a rectangular shape or a profile close to a rectangular shape, it is preferable to perform so-called two-stage baking in which two-stage heating is performed at different temperatures. By performing the two-stage baking, the film is first cured to some extent by the first-stage baking to determine the shape, and further, the film is baked by the second-stage baking to give the necessary durability. The first baking temperature is preferably 90 ° C. to 150 ° C., and the time is preferably 10 to 60 minutes. The second baking temperature is preferably 180 to 250 ° C., and the time is preferably 30 to 90 minutes.
It is also possible to perform a baking process of three or more stages.
The taper angle in the cross-sectional shape of the pattern after the baking step is preferably 60 ° or more, more preferably 70 ° or more, and particularly preferably 80 ° or more.

  Since the photosensitive resin composition of the present invention can obtain a rectangle or a profile close to a rectangle even after the baking step, it is particularly useful as an etching resist.

(MEMS structure and manufacturing method thereof, dry etching method, wet etching method, MEMS shutter device, and image display device)
The manufacturing method of the MEMS (Micro Electro Mechanical Systems) structure of the present invention includes a step of manufacturing a structure using a pattern manufactured by the pattern manufacturing method of the present invention as a sacrificial layer at the time of stacking the structure, and the sacrificial layer. It is preferable to include the process of removing by plasma processing.
The MEMS structure of the present invention is a MEMS structure manufactured using a pattern manufactured by the pattern manufacturing method of the present invention as a sacrificial layer at the time of stacking structures.
The MEMS shutter device of the present invention is a MEMS shutter device manufactured by the method for manufacturing a MEMS structure of the present invention.
The image forming apparatus of the present invention preferably includes the MEMS shutter device of the present invention.
MEMS (Micro Electro Mechanical System) refers to an electromechanical element or system or micromachine having a micro structure of a micro size or less. For example, a mechanical drive component, a sensor, an actuator, and an electronic circuit are included in one silicon substrate, glass Examples include devices integrated on a substrate, an organic material, or the like.
Examples of the MEMS shutter device and the image forming apparatus provided with the MEMS shutter device include those described in JP-T-2008-533510.

When the pattern produced by the pattern production method of the present invention is used as a sacrificial layer for producing a MEMS structure, a metal film is formed on the pattern using various film formation processes such as coating, vapor deposition, sputtering, CVD, and plating. Further, inorganic materials such as metal oxides, silicon compounds, and semiconductors, and organic materials such as polyimide can be stacked. Two or more different materials can be laminated in multiple layers.
The base material for the MEMS sacrificial layer that can be used in the present invention includes silicon, silicon dioxide, silicon nitride, alumina, glass, glass-ceramics, gallium arsenide, indium phosphide, copper, aluminum, nickel, and iron. Steel, copper-silicon alloy, indium-tin oxide coated glass; organic films such as polyimide and polyester; including, but not limited to, any substrate containing patterned regions of metal, semiconductor, and insulating material . Optionally, a baking step can be performed on the substrate to remove absorbed moisture before applying the photosensitive resin composition of the present invention.

When the pattern produced by the pattern production method of the present invention is used as a dry etching resist, dry etching treatment such as ashing, plasma etching, ozone etching and the like can be performed as the etching treatment. In particular, it is preferably used as an etching resist in a dry etching process using a fluorine-based gas.
The dry etching method of the present invention includes a step of performing dry etching using the pattern produced by the pattern production method of the present invention as a dry etching resist, and a step of removing the pattern by plasma treatment or chemical treatment. preferable.
Examples of dry etching materials that can be used in the present invention include silicon, silicon dioxide, silicon nitride, alumina, glass, glass-ceramics, gallium arsenide, indium phosphide, copper, aluminum, nickel, iron, and steel. , Copper-silicon alloys, indium-tin oxide coated glasses; including but not limited to metals, semiconductors, and any substrate containing a patterned region of insulating material.

There is no restriction | limiting in particular as a generation method of plasma, Both a low pressure plasma method and an atmospheric plasma method are applicable.
In the plasma etching, for example, an inert gas selected from helium, argon, krypton, and xenon, O ₂ , CF ₄ , C ₂ F ₄ , N ₂ , CO ₂ , SF ₆ , CHF ₃ , at least O A reactive gas containing N, F, or Cl can be preferably used.

When the pattern produced by the pattern production method of the present invention is used as a wet etching resist, a wet etching treatment with a known agent such as an acid, an alkali, or a solvent can be performed.
The wet etching method of the present invention includes a step of performing wet etching using the pattern produced by the pattern production method of the present invention as a resist for wet etching, and a step of removing the pattern by plasma treatment or chemical treatment. Is preferred.
Examples of wet etching materials that can be used in the present invention include silicon, silicon dioxide, silicon nitride, alumina, glass, glass-ceramics, gallium arsenide, indium phosphide, copper, aluminum, nickel, iron, and steel. , Copper-silicon alloys, indium-tin oxide coated glasses; including but not limited to metals, semiconductors, and any substrate containing a patterned region of insulating material.

  Examples of the wet etching include an oxidative etching treatment with a sodium permanganate aqueous solution, a strong alkaline aqueous solution treatment such as sodium hydroxide, and a hydrofluoric acid treatment.

When the pattern is peeled after the fabrication of the MEMS or after the etching process, peeling can be performed by a known dry plasma process such as ashing or a known wet process such as alkaline chemical treatment. Since the cured product of the present invention is cured through a baking process, peeling by a dry plasma process is particularly preferable.
When used as a sacrificial layer for MEMS, it is preferable to perform peeling by a dry process in order to remove the resist from the complicated shape of the MEMS. In particular, oxygen plasma treatment is preferable.
Even when it is used as a planar resist as a resist for wet etching or dry etching, oxygen plasma treatment is preferably used, but the resist can be peeled and removed by heat treatment with a chemical solution.

  Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” and “%” are based on weight.

In the following synthesis examples and Table 1, the following abbreviations represent the following compounds, respectively.
MATHF: 2-tetrahydrofuranyl methacrylate (synthetic product)
MAEVE: 1-ethoxyethyl methacrylate (manufactured by Wako Pure Chemical Industries)
MATB: Tertiary butyl methacrylate (manufactured by Tokyo Chemical Industry)
OXE-30: 3-ethyl-3 oxetanyl methacrylate (manufactured by Osaka Organic Chemical Industry)
GMA: Glycidyl methacrylate (Wako Pure Chemical Industries)
THFCH ₂ OH: Tetrahydrofurfuryl methacrylate (manufactured by Tokyo Chemical Industry)
St: Styrene DCPM: Dicyclopentanyl methacrylate (manufactured by Tokyo Chemical Industry)
HEMA: 2-hydroxyethyl methacrylate (manufactured by Wako Pure Chemical Industries)
V-65: 2,2′-azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd.)
V-601: Dimethyl-2,2′-azobis (2-methylpropionate) (manufactured by Wako Pure Chemical Industries)
VA-057: 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (manufactured by Wako Pure Chemical Industries, Ltd.)
V-501: 4,4′-azobis (4-cyanovaleric acid) (manufactured by Wako Pure Chemical Industries, Ltd.)
PGMEA: Propylene glycol monomethyl ether acetate (Showa Denko)
Chain transfer agent A: thiomalic acid (manufactured by Tokyo Chemical Industry)
Chain transfer agent B: 3-mercaptopropionic acid (manufactured by Tokyo Chemical Industry)
Chain transfer agent C: Thiopronin (manufactured by Tokyo Chemical Industry)
Chain transfer agent D: thioglycolic acid (manufactured by Tokyo Chemical Industry)
Chain transfer agent E: Captopril (manufactured by Tokyo Chemical Industry)

<Synthesis of Polymer A-1>
<Synthesis Example 1: Synthesis of MATHF>
In a three-necked flask, 50.33 g (0.585 mol) of methacrylic acid and 0.27 g (0.2 mol%) of camphorsulfonic acid were mixed and cooled to 15 ° C. To the solution, 41.00 g (0.585 mol) of 2,3-dihydrofuran was added dropwise. Saturated aqueous sodium hydrogen carbonate solution (500 mL) was added to the reaction mixture, and the mixture was extracted with ethyl acetate (500 mL) and dried over magnesium sulfate. Insoluble matter was filtered, and the filtrate was concentrated under reduced pressure at 40 ° C. or lower, and the colorless oily residue was distilled under reduced pressure to obtain 73.02 g of MATHF having a boiling point (bp.) Of 54 to 56 ° C./3.5 mmHg fraction.

<Synthesis Example 1: Synthesis of specific resin A>
PGMEA (31.0 g) was placed in a three-necked flask and heated to 80 ° C. in a nitrogen atmosphere. MATHHF (19.5 g), HEMA (4.07 g), OXE-30 (17.27 g), V-601 (0.21 g, 0.38 mol% with respect to the monomer), thioapple as a chain transfer agent Acid (0.56 g, 1.5 mol% with respect to the monomer) was dissolved in PGMEA (31.0 g) and added dropwise over 2 hours. After completion of the dropwise addition, the reaction was terminated by stirring for 4 hours. Thereby, specific resin A was obtained. The weight average molecular weight was 19,000.

<Synthesis of Polymers A-2 to A-29>
Each monomer used in the synthesis of the polymer A-1 was changed to a monomer that forms each repeating unit (a1) to (a5) shown in Table 1, and the amount of the monomer that forms each repeating unit is shown in Table 1. Necessary to use the chain transfer agents listed in the table, the points changed to those described, the radical polymerization initiators V-601, VA-057, V-501 and V-65 appropriately used according to the substrate Polymers A-2 to A-29 were respectively synthesized in the same manner as the synthesis of the polymer A-1, except for the points used accordingly. The addition amounts of radical polymerization initiators V-601, VA-057, V-501 and V-65 were adjusted so as to have the molecular weights shown in Table 1, respectively.

  In addition, the molar ratio of Table 1 is a copolymerization ratio of the repeating unit derived from each monomer described in the kind column. In Table 1, “-” indicates that the repeating unit is not used.

(Examples 1-39 and Comparative Examples 1-6)
(1) Preparation of photosensitive resin composition Each component shown in Table 2 below was mixed. Here, for the binder polymer, any of polymers A-1 to A-29 shown in Table 3 below was used. For Comparative Example 3, the composition described in Example 1 of Japanese Patent No. 4302178 was employed.
After making the mixed component uniform solution, it filtered using the filter made from polytetrafluoroethylene which has a 0.1 micrometer pore size, and prepared the photosensitive resin composition of an Example and a comparative example, respectively. The obtained photosensitive resin compositions of Examples and Comparative Examples were used, and evaluations described later were performed. The evaluation results are shown in Table 3 and Table 4.

In addition, the symbol in Table 2 is as follows.
B1: CGI1397 (the following compound, manufactured by Ciba Specialty Chemicals)
B2: α- (p-Toluenesulfonyloxyimino) phenylacetonitrile (the synthesis method is as shown below)
B3: Oxime sulfonate compound synthesized by the following synthesis method B4: Structure shown below (synthesized by the method described in Chem. Commun., 2009, vol.7, p.827)
B5: Structure shown below (synthesized by the method described in US4329300A1)
F1: 9,10-dibutoxyanthracene (DBA) (9,10-dibutoxyanthracene, manufactured by Kawasaki Chemical Industries)
I1: 1,5-diazabicyclo [4.3.0] -5-nonene, manufactured by Tokyo Chemical Industry Co., Ltd., D1313
I2: 2,4,5-triphenylimidazole (Tokyo Chemical Industry Co., Ltd., T0999)
E5: EPICLON EXA-4816 (manufactured by DIC Corporation, epoxy equivalent: 403 g / eq)) D1: Nicarak MW-100LM (manufactured by Sanwa Chemical Co., Ltd.)
E9: JER157S65 (Mitsubishi Chemical Corporation, epoxy equivalent: 200 to 220 g / eq)
J1: Compound W-3 shown below
H1: 3-glycidoxypropyltrimethoxysilane (KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.))
C1: Propylene glycol monomethyl ether acetate

<Synthesis of B2>
Α- (p-toluenesulfonyloxyimino) phenylacetonitrile was synthesized according to the method described in paragraph 0108 of JP-T-2002-528451.

<Method for synthesizing B3>
Aluminum chloride (10.6 g) and 2-chloropropionyl chloride (10.1 g) were added to a suspension of 2-naphthol (10 g) and chlorobenzene (30 mL), and the mixture was heated to 40 ° C. for 2 hours. I let you. Under ice-cooling, 4N HCl aqueous solution (60 mL) was added dropwise to the reaction solution, and ethyl acetate (50 mL) was added for liquid separation. Potassium carbonate (19.2 g) was added to the organic layer, reacted at 40 ° C. for 1 hour, 2N HCl aqueous solution (60 mL) was added and separated, and the organic layer was concentrated, and the crystals were diluted with diisopropyl ether (10 mL). The slurry was reslurried, filtered and dried to obtain a ketone compound (6.5 g).
Acetic acid (7.3 g) and 50% aqueous hydroxylamine solution (8.0 g) were added to a suspension of the obtained ketone compound (3.0 g) and methanol (30 mL), and the mixture was heated to reflux. After allowing to cool, water (50 mL) was added, and the precipitated crystals were filtered, washed with cold methanol, and dried to obtain an oxime compound (2.4 g).
The obtained oxime compound (1.8 g) was dissolved in acetone (20 mL), triethylamine (1.5 g) and p-toluenesulfonyl chloride (2.4 g) were added under ice cooling, and the temperature was raised to room temperature. Reacted for hours. Water (50 mL) was added to the reaction solution, and the precipitated crystals were filtered, reslurried with methanol (20 mL), filtered and dried to obtain B3 (2.3 g).
The ¹ H-NMR spectrum (300 MHz, CDCl ₃ ) of B3 is δ = 8.3 (d, 1H), 8.0 (d, 2H), 7.9 (d, 1H), 7.8 ( d, 1H), 7.6 (dd, 1H), 7.4 (dd, 1H) 7.3 (d, 2H), 7.1 (d.1H), 5.6 (q, 1H), 2 .4 (s, 3H), 1.7 (d, 3H).

<Evaluation of photosensitive resin composition>
(1) Evaluation of sensitivity (without PEB)
A photosensitive resin composition was spin-coated on a silicon wafer having a silicon oxide film, and then prebaked on a hot plate at 90 ° C. for 120 seconds to form a coating film having a thickness of 4 μm.
Next, it exposed through the predetermined | prescribed mask using i line | wire stepper (Canon Co., Ltd. product FPA-3000i5 ^<+> ). After exposure, the substrate was allowed to stand at room temperature for 10 minutes, and then developed with a 0.4 mass% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 60 seconds, followed by rinsing with ultrapure water for 45 seconds. By these operations, the optimum exposure amount (Eopt) when resolving 10 μm line and space at 1: 1 was defined as sensitivity. It can be said that the smaller the sensitivity, the higher the sensitivity. In particular, it is preferable that the sensitivity is lower than 70 mJ / cm ² . PEB is not implemented.

(2) Evaluation of taper angle and pattern profile After a photosensitive resin composition is spin-coated on a silicon wafer having a silicon oxide film, it is pre-baked on a hot plate at 90 ° C. for 120 seconds to form a coating film having a thickness of 4 μm. Formed.
Next, using an i-line stepper (FPA-3000i5 ⁺ manufactured by Canon Inc.), an exposure dose of 70 mJ / cm ^{2 was} exposed through a predetermined mask. After exposure, the substrate was allowed to stand at room temperature for 10 minutes, and then developed with a 0.4 mass% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 60 seconds, followed by rinsing with ultrapure water for 45 seconds. Next, a two-stage baking process (first stage: 140 ° C., 30 minutes, second stage: 230 ° C., 60 minutes) was performed and fired.
Thereafter, a cross section of a 10 μm line & space pattern was observed with a scanning electron microscope (SEM), and the taper angle was measured.
Furthermore, the profile shape was evaluated based on the taper angle and the overall rectangularity. If the profile is closer to a rectangle, a structure having a shape (rectangular shape) that is originally desired for a MEMS resist can be laminated on the resist, and if a resist for dry etching, the material to be etched in the dry etching process. Can be processed precisely. Evaluation points 3 to 5 are determined to be practically acceptable levels. An image of the shape is shown in FIG.
In this evaluation, since the formation of a rectangular line & space pattern is aimed at, a high taper angle is judged better as follows, but if the desired pattern is different, it is not necessarily rectangular. There is no need.
5: Profile of a rectangle with a taper angle of a line section of 80 ° or more and 90 ° or less or a profile close to a rectangle 4: Profile of a tape with a taper angle of a line section of 70 ° or more and less than 80 ° 3: Profile with a taper angle of a line section Trapezoidal profile with 60 ° or more and less than 70 ° 2: Profile with taper angle of line cross section of 40 ° or more and less than 60 ° 1: Profile with taper angle of line cross section of less than 40 °

(3) Evaluation of chemical resistance The film thickness (T1) of the cured film produced in the same process as the pattern profile evaluation was measured. And the board | substrate with which this cured film was formed was immersed in 40 degreeC for 10 minute (s) in 5% oxalic acid aqueous solution. The film thickness (t1) of the cured film after immersion was measured, and the film thickness change rate {| t1-T1 | / T1} × 100 [%] by immersion was calculated. Evaluation points 3 to 5 are determined to be practically acceptable levels.
5: Change in film thickness was less than ± 1%.
4: The film thickness change was ± 1% or more and less than 5%.
3: Change in film thickness was ± 5% or more and less than 10%.
2: The film thickness change was ± 10% or more.
1: Film peeling was confirmed.

(4) Evaluation of Development Defects A photosensitive resin composition was spin-coated on a silicon wafer having a silicon oxide film, and then pre-baked on a hot plate at 90 ° C. for 120 seconds to form a coating film having a thickness of 4 μm.
Next, using an i-line stepper (FPA-3000i5 ⁺ manufactured by Canon Inc.), an exposure dose of 70 mJ / cm ^{2 was} exposed through a predetermined mask. After the exposure, the substrate was allowed to stand at room temperature for 10 minutes, and then developed with a 0.4% by mass aqueous tetramethylammonium hydroxide solution at 23 ° C. for 60 seconds by a puddle method. The substrate after development was observed with an optical microscope, and the number of development defects was counted.
5: Development defects 0 / wafer 4: Development defects 1 to 3 / wafer 3: Development defects 4 to 10 / wafer 2: Development defects 11 to 20 / wafer 1: Development defects 21 / More than wafer

上記比較例３では、特許登録第４３０２１７８号公報の実施例１に記載の感光層を採用した。

In Comparative Example 3, the photosensitive layer described in Example 1 of Japanese Patent Registration No. 4302178 was employed.

  Further, using the photosensitive resin composition of Example 3, in the same manner as in Example 31, (2) taper angle evaluation and pattern profile evaluation, and (5) production and operation evaluation of a MEMS shutter display. went.

  In Examples 1 and 31, the same operation was performed except that the film thickness of the coating film was changed from 4 μm to 10 μm, 50 μm, and 100 μm, respectively, (2) taper angle evaluation and pattern profile evaluation, (3) chemical resistance Table 6 shows the results of evaluation and (4) evaluation of development defects.

As is apparent from the above table, the photosensitive resin composition using the acrylic resin used in the present invention is excellent in sensitivity, has a taper angle close to 90 °, is close to a rectangle or a rectangle, and has few development defects. I understood.
In particular, it was found that the effect of the present invention is more effectively exhibited when a binder polymer having a weight average molecular weight Mw exceeding 5000 is employed.

10: Substrate 12: Pattern 14: Midpoint between the top of the film and the substrate θ: Taper angle

Claims (20)

It contains a carboxyl group at the end of the main chain and contains a repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group. A positive photosensitive resin composition containing a soluble acrylic resin. The positive photosensitive resin composition according to claim 1, wherein the acrylic resin has a repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group represented by the general formula (1).
General formula (1)

(In General Formula (1), R ¹ represents a hydrogen atom or an alkyl group, L represents a divalent linking group, and R ^{2 to} R ⁴ each represents a hydrogen atom, an alkyl group, or a phenyl group. n represents 1 or 2. R ² , R ^3, or R ⁴ may combine with a substituent of L to form a ring. The positive photosensitive resin composition of Claim 1 or 2 whose weight average molecular weights of the said acrylic resin are 5000 or more. The acrylic resin has a repeating unit having a residue in which a carboxy group or a phenolic hydroxyl group is protected with an acid-decomposable group in addition to the repeating unit having a 3-membered ring and / or a 4-membered cyclic ether group. The positive photosensitive resin composition of any one of Claims 1-3 which has these. Furthermore, the positive photosensitive resin composition of any one of Claims 1-4 containing a photo-acid generator. The positive photosensitive resin composition according to claim 5, wherein the photoacid-generating group is an onium salt and / or an oxime sulfonate. The positive photosensitive resin composition of any one of Claims 1-6 which further contains a crosslinking agent. The positive photosensitive resin composition according to any one of claims 1 to 7, further comprising a solvent. A cured film obtained by curing the positive photosensitive resin composition according to claim 1 by applying at least one of light and heat. The cured film according to claim 9, which is an interlayer insulating film. (1) The process of apply | coating the positive photosensitive resin composition of any one of Claims 1-8 on a board | substrate,
(2) a step of removing the solvent from the applied positive photosensitive resin composition;
(3) a step of exposing the positive photosensitive resin composition from which the solvent has been removed with actinic radiation,
(4) a step of developing the exposed positive photosensitive resin composition with an aqueous developer, and
(5) a post-baking step of thermosetting the developed positive photosensitive resin composition;
A method for forming a cured film comprising: The formation method of the cured film of Claim 11 which performs the said image development process without performing heat processing after the exposure in the said exposure process. The positive photosensitive resin composition according to any one of claims 1 to 8, which is used for an etching resist. The positive photosensitive resin composition of any one of Claims 1-8 which is an object for structural members for MEMS. A film forming step of forming a film by removing the solvent from the positive photosensitive resin composition according to claim 1,
An exposure step of exposing the film in a pattern with an actinic ray;
A development step of developing the exposed film with an aqueous developer to form a pattern; and
A baking step of heating the pattern;
A pattern forming method including: The pattern formation method of Claim 15 including the post-exposure process which exposes the said pattern with actinic light after the said image development process and before the said baking process. A step of producing a structure using the pattern produced by the pattern forming method according to claim 15 or 16 as a sacrificial layer when the structure is laminated; and
And removing the sacrificial layer by plasma treatment. A step of performing dry etching using a pattern produced by the pattern forming method according to claim 15 as a dry etching resist; and
Removing the pattern by plasma treatment or chemical treatment;
A dry etching method including: A step of performing wet etching using a pattern produced by the pattern forming method according to claim 15 or 16 as a resist for wet etching; and
Removing the pattern by plasma treatment or chemical treatment;
A wet etching method including: 9. The method according to claim 1, comprising producing an acrylic resin by using a chain transfer agent having a carboxyl group at the time of polymerization of the polymerizable monomer or using a polymerization initiator having a carboxyl group. Of producing a positive photosensitive resin composition.

Images