JP2015179120A - Photosensitive resin composition and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition from which a pattern film can be formed in such a manner that the composition shows high sensitivity and maintains a high residual film ratio without leaving a development residue in a process of forming the pattern film, that the composition shows no degradation in physical properties of a coating film such as an optical transmittance and solvent resistance, and no foaming after a process of high-temperature baking, and that even a thick film can be formed.SOLUTION: The photosensitive resin composition comprises a specific itaconic acid diester copolymer as a component (A), a specific esterified product as a component (B), a compound having two or more epoxy groups as a component (C), and a copolymer comprising a specific structural unit as a component (D).

Description

  The present invention relates to a positive photosensitive resin composition having photosensitivity and its use. Specifically, a photosensitive resin composition capable of forming a pattern film by using a photolithography technique, and a flat panel display (FPD) provided with an interlayer insulating film or a planarizing film formed using the photosensitive resin composition Or relates to a semiconductor device.

Conventionally, photolithography technology has been used to form or process microelements in a wide range of fields including semiconductor integrated circuits such as LSIs, FPD display surfaces, thermal heads and other circuit boards. It's being used. In the photolithography technique, a photosensitive resin composition is used to form a resist pattern. In recent years, as a new application of these photosensitive resin compositions, attention is paid to a technique for forming an interlayer insulating film and a planarizing film such as a semiconductor integrated circuit and an FPD. In particular, there are strong market demands for higher definition of FPD display surfaces and shortening of manufacturing processes of semiconductor elements represented by TFTs.
In a manufacturing process of a semiconductor element typified by a TFT or the like, in the process of forming an interlayer insulating film or a planarizing film, the time for forming the interlayer insulating film or the planarizing film may be shortened for the purpose of improving productivity. It has been demanded. Furthermore, in order to respond to all panel designs, these members are also required to be formed without any problem with a film thickness of 1.5 μm to 5.0 μm. Therefore, for photosensitive resin compositions for forming interlayer insulation films and planarization films, the sensitivity does not change greatly even when the film thickness changes with high sensitivity, and foaming is a problem when forming thick films. There is a strong demand for materials that do not cause this.
In order to obtain an interlayer insulating film and a planarizing film having the above-mentioned characteristics, the role of the alkali-soluble resin and the photosensitive agent in the photosensitive resin composition is great, and the photosensitive resin composition used for such applications A lot of research has been done.

  For example, in Patent Document 1, by using an unsaturated carboxylic acid and a radical polymerizable compound having an epoxy group as an alkali-soluble resin of a photosensitive resin composition for an interlayer insulating film or a planarizing film, high sensitivity and high A technique for forming a resolution pattern film is disclosed. However, since the alkali-soluble resin has an unsaturated carboxylic acid and an epoxy group as structural units, a part of the cross-linking reaction proceeds in the pre-baking step when forming the insulating film, and the alkali developing solution in the subsequent developing step. There is a problem that the solubility in the water becomes poor and sufficient sensitivity cannot be obtained.

  Patent Document 2 discloses that high resolution can be obtained by using an acrylic resin and a specific photosensitive agent as an alkali-soluble resin in a photosensitive resin composition for an interlayer insulating film or a planarizing film. Is disclosed. However, the alkali-soluble resin has a problem that the film density is high and foaming occurs when a thick film is formed.

  Furthermore, Patent Document 3 uses a copolymer having styrenes, (meth) acrylic acid, and hydroxyalkyl esters as structural units as an alkali-soluble resin of a photosensitive resin composition for an interlayer insulating film or a planarizing film. Thus, it is disclosed that good insulating properties can be obtained. However, when a large amount of styrenes is introduced into the resin, the hydrophobicity of the resin increases, so that the remaining film ratio during development can be maintained high, but the sensitivity is low, the development residue increases, and sufficient There is a problem that developability cannot be obtained.

  In order to solve such problems, there is no development residue in a photosensitive resin composition used for an interlayer insulating film or a planarizing film such as an FPD or a semiconductor device while maintaining a high residual film ratio with high sensitivity. Therefore, it is required to form a pattern film that can be formed even with a thick film without foaming.

JP-A-7-248629 JP 2003-255521 A JP 2004-4233 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a specific itaconic acid diester copolymer, a specific esterified product, a compound having two or more epoxy groups, and a specific constituent unit. By using a polymer, in the pattern film formation process, while maintaining high sensitivity, there is no development residue while maintaining a high residual film ratio, and light transmittance, solvent resistance, etc. even after high temperature baking It is an object of the present invention to provide a photosensitive resin composition capable of forming a pattern film that can be formed with a thick film without foaming without impairing physical properties.

  The second object of the present invention is to provide an FPD or a semiconductor device having a planarizing film or an interlayer insulating film formed of the above-described excellent photosensitive resin composition.

  As a result of intensive studies under such background, the present inventors have found that a specific itaconic acid diester copolymer as the component (A), a specific esterified product as the component (B), and a component (C). A photosensitive resin composition containing a compound having two or more epoxy groups as a component and a copolymer consisting of a specific structural unit as a component (D), the component ratio of each component being 100 parts by mass of the component (A) On the other hand, it discovered that the said subject could be solved by using as component (B) 5-50 mass parts, component (C) 10-70 mass parts, and component (D) 10-50 mass parts, and came to complete this invention. It was.

（式中、Ｒ^１およびＲ^２は、それぞれ独立して炭素数１〜８の直鎖アルキル基、炭素数３〜８の分岐アルキル基または炭素数６〜１０のシクロアルキル基）

（式中のＲ^３は水素原子またはメチル基）

（式中のＲ^４は水素原子またはメチル基、Ｒ^５は炭素数１〜１２の直鎖アルキル基、炭素数３〜１２の分岐アルキル基、炭素数６〜１２のアリール基、ベンジル基、炭素数１〜１２のヒドロキシアルキル基または主環構成炭素数３〜１２の脂環式炭化水素基）
成分（Ｂ）は下記式（４）で表される３官能フェノール性化合物と下記式（４）′で表されるキノンジアジド化合物とをエステル化反応させて得られる、キノンジアジド基を有するエステル化物であり、

（Ｒ^６、Ｒ^７は水素またはＳＯ_２Ｘを表し、Ｘはハロゲンを表す。ただし、Ｒ^６とＲ^７のどちらか一つは必ず水素を表し、Ｒ^６とＲ^７のどちらか一つは必ずＳＯ_２Ｘを表す）
成分（Ｃ）は２個以上のエポキシ基を有する化合物であり、
成分（Ｄ）は下記式（５）で表されるイタコン酸ジエステル単量体から誘導される構成単位（ｄ１）、下記式（６）で表される芳香族ビニル単量体から誘導される構成単位（ｄ２）、下記式（７）で表されるα，β−不飽和カルボン酸単量体から誘導される構成単位（ｄ３）および下記式（８）で表される（メタ）アクリル酸エステル単量体から誘導される構成単位（ｄ４）からなる共重合体であって、成分（Ｄ）の共重合体１００質量％中における各構成単位の割合がそれぞれ、構成単位（ｄ１）３〜５０質量％、構成単位（ｄ２）２０〜７０質量％、構成単位（ｄ３）１０〜３５質量％および（ｄ４）３〜５５質量％、かつ（ｄ１）と（ｄ２）との合計量が３０〜８７質量％である共重合体である。

（式中、Ｒ^８およびＲ^９は、それぞれ独立して炭素数１〜８の直鎖アルキル基、炭素数３〜８の分岐アルキル基または炭素数６〜１０のシクロアルキル基）

（式中、Ｒ^１０およびＲ^１１は、それぞれ独立して水素原子またはメチル基）

（式中のＲ^１２は水素原子またはメチル基）

（式中のＲ^１３は水素原子またはメチル基、Ｒ^１４は炭素数１〜１２の直鎖アルキル基、炭素数３〜１２の分岐アルキル基、炭素数６〜１２のアリール基、ベンジル基、炭素数１〜１２のヒドロキシアルキル基または主環構成炭素数３〜１２の脂環式炭化水素基） That is, this invention contains a component (A), a component (B), a component (C), and a component (D), and the component ratio of each component is component (B) 5 with respect to 100 mass parts of component (A). The photosensitive resin composition which is -50 mass parts, 10-70 mass parts of component (C), and 10-50 mass parts of component (D),
Component (A) is a structural unit (a1) derived from an itaconic acid diester monomer represented by the following formula (1), an α, β-unsaturated carboxylic acid monomer represented by the following formula (2) Itaconic acid diester copolymer comprising a structural unit derived from (a2) and a structural unit (a3) derived from a (meth) acrylic acid ester monomer represented by the following formula (3):

(Wherein, R ¹ and R ² are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms).

(Wherein R ³ is a hydrogen atom or a methyl group)

(Wherein R ⁴ is a hydrogen atom or a methyl group, R ⁵ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon A hydroxyalkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms constituting the main ring)
Component (B) is an esterified product having a quinonediazide group obtained by esterifying a trifunctional phenolic compound represented by the following formula (4) and a quinonediazide compound represented by the following formula (4) ′. ,

(R ⁶ and R ⁷ represent hydrogen or SO ₂ X, and X represents a halogen. However, one of R ⁶ and R ⁷ always represents hydrogen, and one of R ⁶ and R ⁷ represents Always represents SO ₂ X)
Component (C) is a compound having two or more epoxy groups,
Component (D) is a structural unit derived from an itaconic acid diester monomer represented by the following formula (5), a structure derived from an aromatic vinyl monomer represented by the following formula (6) Unit (d2), structural unit (d3) derived from an α, β-unsaturated carboxylic acid monomer represented by the following formula (7) and (meth) acrylic acid ester represented by the following formula (8) A copolymer comprising a structural unit (d4) derived from a monomer, wherein the proportion of each structural unit in 100% by mass of the copolymer of component (D) is from 3 to 50 structural units (d1). Mass%, structural unit (d2) 20-70 mass%, structural unit (d3) 10-35 mass% and (d4) 3-55 mass%, and the total amount of (d1) and (d2) is 30-87. It is a copolymer which is mass%.

(Wherein R ⁸ and R ⁹ are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms).

(Wherein R ¹⁰ and R ¹¹ are each independently a hydrogen atom or a methyl group)

(Wherein R ¹² is a hydrogen atom or a methyl group)

(In the formula, R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon A hydroxyalkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms constituting the main ring)

  Furthermore, in the present invention, the proportion of each constituent unit in 100% by mass of the copolymer of the component (A) is 2 to 50% by mass, (a2) 6 to 30% by mass, and (a3), respectively. ) It is related with the photosensitive resin composition characterized by being 35-90 mass%.

Furthermore, in the present invention, as the structural unit (a3) in which the component (A) is derived from the (meth) acrylic acid ester monomer represented by the formula (3), R ⁵ has 1 to 12 carbon atoms. A linear alkyl group, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, or an alicyclic hydrocarbon group having 3 to 12 main carbon atoms. Photosensitive resin characterized in that it is an itaconic acid diester copolymer containing a unit (a3X) and at least one structural unit (a3Y) in which R ⁵ is selected from a hydroxyalkyl group having 1 to 12 carbon atoms. Relates to the composition.

  Furthermore, this invention relates to the flat display which has a pattern film obtained from this photosensitive resin composition, and a semiconductor device.

  The photosensitive resin composition of the present invention has a high sensitivity in a development process for forming a pattern film using a photolithography technique, maintains a high residual film ratio, has no development residue, and has a high temperature such as post-baking. Even after baking, a patterned film that can be formed as a thick film without foaming can be formed without impairing the coating properties such as light transmittance and solvent resistance. And the FPD and semiconductor device which have the outstanding characteristic can be provided by using this photosensitive resin composition.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments embodying the present invention will be described in detail.
The photosensitive resin composition of the present invention contains the following component (A), component (B), component (C) and component (D), and the component ratio of each component is (A) 100 parts by mass. (B) 5 to 50 parts by mass, (C) 10 to 70 parts by mass, and (D) 10 to 50 parts by mass.
Component (A): Specific itaconic acid diester copolymer Component (B): Specific esterified component Component (C): Compound having two or more epoxy groups Component (D): Copolymer consisting of specific structural units Coalescence

  Hereinafter, each component will be described in order.

<Component (A): Specific Itaconic Acid Diester Copolymer>
The specific itaconic acid diester copolymer of component (A) is represented by the structural unit (a1) derived from the itaconic acid diester monomer represented by the following formula (1) and the following formula (2): From the structural unit (a2) derived from the α, β-unsaturated carboxylic acid monomer and the structural unit (a3) derived from the (meth) acrylate monomer represented by the following formula (3) Itaconic acid diester copolymer. The proportion of each constituent unit in 100% by mass of the copolymer of component (A) is 2 to 50% by mass, (a2) 6 to 30% by mass, and (a3) 35 to 90% by mass, respectively. It is.

（式中、Ｒ^１およびＲ^２は、それぞれ独立して炭素数１〜８の直鎖アルキル基、炭素数３〜８の分岐アルキル基または炭素数６〜１０のシクロアルキル基）

(Wherein, R ¹ and R ² are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms).

（式中のＲ^３は水素原子またはメチル基）

(Wherein R ³ is a hydrogen atom or a methyl group)

（式中のＲ^４は水素原子またはメチル基、Ｒ^５は炭素数１〜１２の直鎖アルキル基、炭素数３〜１２の分岐アルキル基、炭素数６〜１２のアリール基、ベンジル基、炭素数１〜１２のヒドロキシアルキル基または主環構成炭素数３〜１２の脂環式炭化水素基）

(Wherein R ⁴ is a hydrogen atom or a methyl group, R ⁵ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon A hydroxyalkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms constituting the main ring)

  The structural units represented by the formulas (1) to (3) are derived from monomers (monomers for respective structural units) represented by the following formulas (1) ′ to (3) ′, respectively.

（式中、Ｒ^１およびＲ^２は、それぞれ式（１）におけるものと同じである。）

(In the formula, R ¹ and R ² are the same as those in formula (1).)

（式中のＲ^３は式（２）におけるものと同じである。）

(R ³ in the formula is the same as that in formula (2).)

（式中のＲ^４、Ｒ^５は、それぞれ式（３）におけるものと同じである。）

(R ⁴ and R ⁵ in the formula are the same as those in formula (3).)

[Structural Unit Derived from Itaconic Acid Diester Monomer (a1)]
Since the structural unit (a1) derived from the itaconic acid diester monomer is a diester group, it has a high affinity for an alkali developer, and thus good sensitivity and developability can be obtained.
R ¹ and R ² in the formula (1) are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms.
If the straight-chain alkyl group and the branched alkyl group have more than 8 carbon atoms and the cycloalkyl group has more than 10 carbon atoms, the solubility in the developer is lowered and the developability is deteriorated. R ¹ and R ² in the formula (1) may be the same substituent or different substituents, but are preferably the same structure from the viewpoint of availability.
The structural unit (a1) is contained in 2 to 50% by mass in 100% by mass of the copolymer, and preferably 2 to 40% by mass from the viewpoint of sensitivity and developability. When content of a structural unit (a1) is less than 2 mass%, the solubility to a developing solution will fall and developability will deteriorate. If it exceeds 50% by mass, the developed residual film ratio decreases.

[Structural Unit Derived from α, β-Unsaturated Carboxylic Acid Monomer (a2)]
The structural unit (a2) derived from the α, β-unsaturated carboxylic acid monomer is a component that contributes to developability in the development process. R ³ in the formula (2) is a hydrogen atom or a methyl group. From the viewpoint of copolymerizability, R ³ is preferably a methyl group.
The structural unit (a2) is contained in an amount of 6 to 30% by mass in 100% by mass of the copolymer, and is preferably contained in an amount of 10 to 25% by mass from the viewpoints of sensitivity, developability and development residual film ratio. When content of a structural unit (a2) is less than 6 mass parts, the solubility to a developing solution will fall and developability will deteriorate. On the other hand, when the content of the structural unit (a2) exceeds 30 parts by mass, the remaining film ratio decreases because the solubility in the developer becomes too high.

[Structural unit derived from (meth) acrylate monomer (a3)]
The structural unit (a3) derived from the (meth) acrylic acid ester monomer can be added for the purpose of adjusting sensitivity and developability and adjusting the remaining film ratio during development. In the formula (3), R ⁴ is a hydrogen atom or a methyl group, R ⁵ is an alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon It is a C1-C12 hydroxyalkyl group or a main ring constituent C3-C12 alicyclic hydrocarbon group.
From the viewpoint of copolymerizability, R ⁴ is preferably a methyl group. When the number of carbon atoms in R ⁵ exceeds 12, the copolymerizability is lowered, which causes a problem. These (meth) acrylic acid ester monomers for inducing the structural unit (a3) can be used alone or in combination of two or more for the purpose of adjusting developability.
As the structural unit (a3) represented by the formula (3), R ⁴ is a hydrogen atom or a methyl group, R ⁵ is an alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, carbon At least one structural unit (a3X) selected from an aryl group, a benzyl group, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms in the main ring, R ⁴ is a hydrogen atom or a methyl group, R ⁵ Can be used in combination by selecting at least one structural unit (a3Y) selected from hydroxyalkyl groups having 1 to 12 carbon atoms. The structural unit (a3X) is a structural unit with high hydrophobicity, and the structural unit (a3Y) is a structural unit with high hydrophilicity. The combined use of the structural unit (a3X) and the structural unit (a3Y) is advantageous from the viewpoints of developability and development residual film ratio. Preferably, as the structural unit (a3X), R ⁵ is an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 6 to 10 carbon atoms, and preferably as the structural unit (a3Y), R ⁵ has 1 carbon atom. ~ 3 hydroxyalkyl groups.
The structural unit (a3) is contained in 35 to 90% by mass in 100% by mass of the copolymer, and preferably 40 to 85% by mass from the viewpoint of sensitivity and developability. When the content of the structural unit (a3) is less than 35% by mass, the developed residual film ratio is decreased, and when it exceeds 90% by mass, the solubility in the developer is decreased and the developability is deteriorated.
The component (A) is a copolymer composed of the structural units (a1), (a2) and (a3) shown above, so that the photosensitive resin is excellent in sensitivity, developability, residual film ratio and solvent resistance. A composition can be provided.

[Synthesis Method of Copolymer (A)]
In synthesizing the copolymer (A), a known radical polymerization method can be applied. At that time, the monomers for deriving the structural unit (a1), the structural unit (a2) and the structural unit (a3), which are copolymerization components, can be charged all at once into the polymerization kettle, or dropped into the reaction system in a divided manner. May be.
As the polymerization solvent used for obtaining the copolymer of component (A), generally known solvents can be used.
As the polymerization initiator used for obtaining the copolymer of component (A), those generally known as radical polymerization initiators can be used. Specific examples thereof include an azo polymerization initiator, an azo polymerization initiator having no cyano group, an organic peroxide, and hydrogen peroxide. When a peroxide is used as the radical polymerization initiator, it may be used as a redox polymerization initiator in combination with a reducing agent.
The weight average molecular weight of the component (A) copolymer is 5,000 to 60,000, and preferably 5,000 to 30,000 from the viewpoint of developability. When the mass average molecular weight is less than 5,000, pattern flow occurs during post-baking, which may result in insufficient resolution of the pattern film and deterioration of solvent resistance. When the mass average molecular weight exceeds 60,000, solubility in a developer is poor, and developability is deteriorated.

<Component (B): Specific esterified product>
The esterified product of component (B) can be obtained by esterifying a trifunctional phenolic compound represented by the following formula (4) and a quinonediazide compound represented by the following formula (4) ′.

（Ｒ^６、Ｒ^７は水素またはＳＯ_２Ｘを表し、Ｘはハロゲンを表す。ただし、Ｒ^６とＲ^７のどちらか一つは必ず水素を表し、Ｒ^６とＲ^７のどちらか一つは必ずＳＯ_２Ｘを表す）

(R ⁶ and R ⁷ represent hydrogen or SO ₂ X, and X represents a halogen. However, one of R ⁶ and R ⁷ always represents hydrogen, and one of R ⁶ and R ⁷ represents Always represents SO ₂ X)

Examples of the quinonediazide compound that can be obtained by esterifying a quinonediazide compound and a phenolic compound are represented by 1,2-naphthoquinonediazide-5-sulfonyl chloride, 1,2-naphthoquinonediazide-4-sulfonylchloride, and the like. Naphthoquinone diazide sulfonic acid halide is used.
When the ester compound of component (B) is exposed through a photomask in an exposure step by photolithography, a photoisomerization reaction of an esterified product having a quinonediazide group occurs in the exposed portion to generate a carboxyl group, and then It can be dissolved in the developer in the development step. On the other hand, since the unexposed part has a dissolution inhibiting ability with respect to the developer, a film can be formed. That is, since the component (B) can be exposed through a photomask to exhibit a difference in solubility in a developer in the subsequent development process, a pattern film can be obtained.

The esterification rate of the esterified product of component (B) is 20 to 95%, and preferably 50 to 95% from the viewpoint of sensitivity. However, the esterification rate is represented by the following formula (I).

Esterification rate (%) = (Z / 3) × 100 Formula (I)
(Z represents 3 × (area ratio of 3 mol body) + 2 × (area ratio of 2 mol body) + 1 × (area ratio of 1 mol body), and the area ratio is a value calculated from a chart of high performance liquid chromatography. )

When the esterification rate is less than 20 mol%, the sensitivity and developability are lowered. When the esterification rate is more than 95 mol%, the compatibility with the copolymer is deteriorated, the pattern film is phase-separated, and the transmittance is lowered. .
The composition ratio of the esterified product of component (B) in the photosensitive resin composition is preferably 5 to 50 parts by mass with respect to 100 parts by mass of the copolymer of component (A), from the viewpoints of sensitivity, developability and transparency. Is 15 to 35 parts by mass. When the component ratio of the component (B) is less than 5 parts by mass, the sensitivity and developability are deteriorated. When it exceeds 50 mass parts, compatibility with a copolymer will deteriorate and the transmittance | permeability will fall.

<Component (C): Compound having two or more epoxy groups>
The epoxy group of the compound having two or more epoxy groups used in the photosensitive resin composition undergoes a thermosetting reaction at high temperature baking with the side chain carboxyl group of the copolymer (A) to form a crosslinked film. be able to.
Among epoxy resins as compounds having two or more epoxy groups, epoxy resins represented by the following formulas (9), (11), and (12) are particularly preferable.

（式中、Ｒ^１５、Ｒ^１６、Ｒ^１７、Ｒ^１８、Ｒ^１９、Ｒ^２０、Ｒ^２１はそれぞれ独立して水素原子、炭素数１〜４のアルキル基または下記式（１０）を表し、

(Wherein R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or the following formula (10):

（式中、Ｒ^２２は、水素原子または炭素数１〜４のアルキル基を表し、ｑは０〜２の整数であり、ｊ、ｌ、ｒはそれぞれ独立して０〜４の整数であり、ｋは０〜６の整数であり、ｏおよびｐは０〜２の整数である）

(Wherein R ²² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, q is an integer of 0 to 2, j, l and r are each independently an integer of 0 to 4, k is an integer of 0 to 6, and o and p are integers of 0 to 2)

（式中、Ｒ^２３は炭素数１〜１０の炭化水素基、Ｓは１〜３０の整数、ｔは１〜６の整数である。）

(In the formula, R ²³ is a hydrocarbon group having 1 to 10 carbon atoms, S is an integer of 1 to 30, and t is an integer of 1 to 6.)

（式中、Ｒ^２４、Ｒ^２５、Ｒ^２６、Ｒ^２７、Ｒ^２８、Ｒ^２９、Ｒ^３０、Ｒ^３１はそれぞれ独立して水素原子、炭素数１〜４のアルキル基を表し、ｕ、ｖ、ｗ、ｘはそれぞれ独立して０〜４の整数であり、ｙは０〜３の整数である）

(In the formula, R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁸ , R ²⁹ , R ³⁰ , R ³¹ each independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, u, v, w and x are each independently an integer of 0 to 4, and y is an integer of 0 to 3).

Among the epoxy resins represented by the formula (9), VG3101L manufactured by Printec Co., Ltd. is preferable, and among the epoxy resins represented by the formula (11), EHPE-3150 manufactured by Daicel Chemical Industries, Ltd. is preferable. Among the epoxy resins represented by the formula (12), Epicoat 828, Epicoat 834, and Epicoat 1001 manufactured by Japan Epoxy Resin Co., Ltd. are preferable.
The component ratio of the component (C) in the photosensitive resin composition is 10 to 70 parts by mass with respect to 100 parts by mass of the copolymer of the component (A), and preferably 30 to 30% in terms of compatibility and solvent resistance. 65 parts by mass. When this composition ratio is less than 10 parts by mass, the solvent resistance of the pattern film (cured film) becomes insufficient, and when it exceeds 70 parts by mass, the compatibility with the copolymer deteriorates and the transmittance decreases.

<Component (D): Copolymer comprising specific structural units>
The component (D) copolymer keeps an appropriate film density when heated with the copolymer (A) when forming a thick film, and therefore smoothes out nitrogen gas generated during full exposure (bleaching) and post-bake. Therefore, the foaming phenomenon can be suppressed.
Component (D) is derived from a structural unit (d1) derived from an itaconic acid diester monomer represented by the following formula (5) and an aromatic vinyl monomer represented by the following formula (6). Structural unit (d2), structural unit (d3) derived from an α, β-unsaturated carboxylic acid monomer represented by the following formula (7), and (meth) acrylic acid represented by the following formula (8) It is a copolymer comprising a structural unit (d4) derived from an ester monomer.

（式中、Ｒ^８およびＲ^９は、それぞれ独立して炭素数１〜８の直鎖アルキル基、炭素数３〜８の分岐アルキル基または炭素数６〜１０のシクロアルキル基）

(Wherein R ⁸ and R ⁹ are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms).

（式中、Ｒ^１０およびＲ^１１は、それぞれ独立して水素原子またはメチル基）

(Wherein R ¹⁰ and R ¹¹ are each independently a hydrogen atom or a methyl group)

（式中のＲ^１２は水素原子またはメチル基）

(Wherein R ¹² is a hydrogen atom or a methyl group)

（式中のＲ^１３は水素原子またはメチル基、Ｒ^１４は炭素数１〜１２の直鎖アルキル基、炭素数３〜１２の分岐アルキル基、炭素数６〜１２のアリール基、ベンジル基、炭素数１〜１２のヒドロキシアルキル基または主環構成炭素数３〜１２の脂環式炭化水素基）

(In the formula, R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon A hydroxyalkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms constituting the main ring)

  The structural units represented by the formulas (5) to (8) are derived from monomers (monomers for respective structural units) represented by the following formulas (5) ′ to (8) ′, respectively.

（式中、Ｒ^８およびＲ^９は、それぞれ式（５）におけるものと同じである。）

(In the formula, R ⁸ and R ⁹ are the same as those in formula (5).)

（式中、Ｒ^１０およびＲ^１１は、それぞれ式（６）におけるものと同じである。）

（式中のＲ^１２は式（７）におけるものと同じである。）

(Wherein R ¹⁰ and R ¹¹ are the same as those in formula (6)).

(R ¹² in the formula is the same as that in formula (7).)

（式中のＲ^１３、Ｒ^１４は、それぞれ式（８）におけるものと同じである。）

(R ¹³ and R ¹⁴ in the formula are the same as those in formula (8).)

[Structural Unit (d1) Derived from Itaconic Acid Diester Monomer]
The structural unit (d1) derived from the itaconic acid diester monomer is introduced to adjust the film density with the copolymer of the component (A) and to adjust the developability.
R ⁸ and R ⁹ in the formula (5) are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms.
If the straight-chain alkyl group and the branched alkyl group have more than 8 carbon atoms and the cycloalkyl group has more than 10 carbon atoms, the solubility in the developer is lowered and the developability is deteriorated. R ⁸ and R ⁹ in the formula (5) may be the same substituent or different substituents, but are preferably the same structure from the viewpoint of availability.
The structural unit (d1) is contained in 3 to 50% by mass in 100% by mass of the copolymer, and preferably 10 to 30% by mass in terms of developability and foaming. At this time, the total amount of (d1) and (d2) is included in the range of 30 to 87% by mass. When the content of the structural unit (d1) is less than 3% by mass, the compatibility with the component (A) is deteriorated, the film density is locally increased, and foaming occurs. On the other hand, when the content of the structural unit (d1) exceeds 50% by mass, the compatibility with the component (A) is deteriorated, the film density is locally increased, and foaming may occur. Decreases and developability deteriorates.

[Structural unit derived from aromatic vinyl monomer (d2)]
The aromatic vinyl monomer for deriving the structural unit (d2) is an itaconic acid diester monomer for deriving the structural unit (d1) during polymerization, or an α, β-unsaturated carboxylic acid monomer for deriving the structural unit (d3). Copolymerizability with the (meth) acrylic acid ester monomer that induces the monomer and the structural unit (d4) can be improved. The aromatic vinyl monomer from which the structural unit (d2) is derived includes the itaconic acid diester monomer of the formula (5) ′, the α, β-unsaturated carboxylic acid monomer of the formula (7) ′ and the formula ( 8) Each structural unit derived from a monomer having a different copolymerization property at the time of the polymerization reaction because any of the three monomers of the (meth) acrylic acid ester monomer has good copolymerizability. Can be smoothly introduced into the copolymer, and a copolymer having uniform properties can be obtained without uneven distribution of the copolymer composition.
R ¹⁰ and R ¹¹ in Formula (6) are each independently a hydrogen atom or a methyl group, and R ¹⁰ and R ¹¹ are preferably a hydrogen atom from the viewpoint of developability.
The structural unit (d2) is contained in an amount of 20 to 70% by mass in 100% by mass of the copolymer, and preferably 40 to 60% by mass in terms of developability and foaming. At this time, the total amount of (d1) and (d2) is included in the range of 30 to 87% by mass. When the content of the structural unit (d2) is less than 20% by mass or more than 70% by mass, the balance of copolymerization is lost, and a desired copolymer cannot be obtained. It becomes higher and foaming and developability deteriorate.

[Structural Unit Derived from α, β-Unsaturated Carboxylic Acid Monomer (d3)]
The structural unit (d3) derived from the α, β-unsaturated carboxylic acid monomer is a component that contributes to developability in the development process. R ¹² in the formula (7) is a hydrogen atom or a methyl group. From the viewpoint of heat resistance, R ¹² is preferably a methyl group.
The structural unit (d3) is contained in 10 to 35% by mass in 100% by mass of the copolymer, and is preferably contained in 15 to 30% by mass in terms of both developability and remaining film ratio. When the content of the structural unit (a3) is less than 10% by mass, the hydrophobicity is increased, the compatibility with the component (A) is deteriorated, the film density is locally increased, foaming occurs, and Solubility decreases and developability deteriorates. On the other hand, if the content of the structural unit (d3) exceeds 35% by mass, the solubility in the developer becomes too high, the remaining film ratio decreases, and the hydrophilicity becomes too high. The compatibility deteriorates, and the film density locally increases and foaming occurs.

[Structural unit derived from (meth) acrylate monomer (d4)]
The structural unit (d4) derived from the (meth) acrylic acid ester monomer can be added for the purpose of adjusting developability, adjusting the remaining film ratio during development, and adjusting the resolution. In the formula (8), R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is an alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon It is a C1-C12 hydroxyalkyl group or a main ring constituent C3-C12 alicyclic hydrocarbon group.
From the viewpoint of heat resistance, R ¹³ is preferably a methyl group. When the number of carbon atoms in R ¹⁴ exceeds 12, the copolymerizability is lowered, which causes a problem. These (meth) acrylic acid ester monomers for inducing the structural unit (d4) can be used alone or in combination of two or more for the purpose of adjusting developability.
The structural unit (d4) is contained in the range of 3 to 55% by mass in 100% by mass of the copolymer. From the viewpoints of foaming, developability and transparency, it is preferably contained in an amount of 10 to 35% by mass. If the content of the structural unit (d4) is less than 3% by mass, the solubility in the developer cannot be obtained, the developability is deteriorated, the compatibility with the component (A) is deteriorated, and the film density is locally high. Foaming occurs. When the content of the structural unit (d4) exceeds 55% by mass, the compatibility is deteriorated, and the foaming occurs because the permeability is lowered and the film density is locally increased.

[Synthesis Method of Copolymer (D)]
In synthesizing the copolymer (D), a known radical polymerization method can be applied. At that time, it is also possible to charge the polymerization vessel in a batch with monomers that respectively derive the structural unit (d1), the structural unit (d2), the structural unit (d3), and the structural unit (d4), which are copolymerization components. It may be dropped into the reaction system.
As the polymerization solvent used for obtaining the copolymer of the component (D), generally known solvents can be used.
As the polymerization initiator used for obtaining the copolymer of component (D), those generally known as radical polymerization initiators can be used. Specific examples thereof include an azo polymerization initiator, an azo polymerization initiator having no cyano group, an organic peroxide, and hydrogen peroxide. When a peroxide is used as the radical polymerization initiator, it may be used as a redox polymerization initiator in combination with a reducing agent.
The weight average molecular weight of the copolymer of component (D) is preferably 5,000 to 30,000, and preferably 10,000 to 20,000 in terms of both developability and solvent resistance. When the mass average molecular weight is less than 5,000, the film strength is insufficient and the solvent resistance is deteriorated. When the mass average molecular weight exceeds 30,000, the solubility in a developer is lowered and the developability is deteriorated.
The constituent ratio of the component (D) in the photosensitive resin composition is 10 to 50 parts by mass with respect to 100 parts by mass of the copolymer of the component (A), and preferably 15 to 40 parts by mass from the aspect of suppressing foaming. It is. When this proportion is less than 10 parts by mass, the foaming property is deteriorated, and when it exceeds 50 parts by mass, the sensitivity is lowered.

<Other additive components>
In the photosensitive resin composition of the present invention, additives such as a solvent, a curing accelerator, an adhesion improving aid, and a surfactant can be blended without departing from the object of the present invention.

(solvent)
A known solvent that can be used for the photosensitive resin composition can be used as the solvent. Specific examples of the solvent include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate, and diethylene glycol dimethyl ether. , Diethylene glycol dialkyl ethers such as diethylene glycol diethyl ether and diethylene glycol methyl ethyl ether, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether Propylene glycol monoalkyl ether acetates such as acetate, lactic esters such as methyl lactate and ethyl lactate, aromatic hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone, 2-heptanone and cyclohexanone, N, N-dimethyl Examples include amides such as acetamide and N-methylpyrrolidone, and lactones such as γ-butyrolactone. These solvents can be used alone or in admixture of two or more.

(Curing accelerator)
The curing accelerator can promote the crosslinking reaction between the epoxy group of the component (C) and the carboxyl group of the side chain of the component (A) copolymer. Examples of the curing accelerator include aromatic sulfoniums such as San-Aid SI-45L, Sun-Aid SI-60L, Sun-Aid SI-80L, Sun-Aid SI-100L, Sun-Aid SI-110L, and Sun-Aid SI-150L manufactured by Sanshin Chemical Industry Co., Ltd. Salt, diazabicycloundecene salts such as U-CAT SA102, U-CAT SA106, U-CAT SA506, U-CAT SA603, U-CAT 5002, etc. manufactured by San Apro Co., Ltd., and CPI-100P manufactured by San Apro Co., Ltd. Photoacid generators such as CPI-101A, CPI-200k, and CPI-210s, and imidazoles such as Curesol 1B2PZ manufactured by Shikoku Kasei Kogyo Co., Ltd.
The composition ratio of the curing accelerator is usually 0.1 to 15 parts by mass with respect to 100 parts by mass of the component (C).

(Adhesion improvement aid and surfactant)
If necessary, the photosensitive resin composition of the present invention may further contain an adhesion improving aid, a surfactant and the like. Examples of the adhesion improving aid include alkyl imidazoline, polyhydroxystyrene, polyvinyl methyl ether, t-butyl novolac, epoxy silane, silane coupling agent and the like. Examples of surfactants include, for example, TSF-431, TSF-433, TSF-437 manufactured by Momentive Performance Materials Japan, <Novec> HFE manufactured by Sumitomo 3M Co., Ltd., Dainippon Ink & Chemicals, Inc. ) Manufactured by MegaFuck F-477, F-483, F-554, TF-1434, TEGO-made Glide-410, Glide-440, Glide-450, Glide-B1484, and the like.

(Contrast improver)
The photosensitive resin composition of the present invention is blended with a phenolic compound represented by the above formula (4) or the following formulas (13), (14), (15), and (16) for the purpose of improving contrast. can do. The phenol group of these phenolic compounds causes an azo coupling reaction with the diazo group of the photosensitive agent of component (B) in the unexposed area where no light is irradiated, thereby enhancing the dissolution inhibiting effect of component (B). As a result, compared to the case where these phenolic compounds are not used, the difference in solubility in the alkaline developer between the exposed area and the unexposed area can be increased (contrast increased), so the remaining film ratio and resolution are improved. Can be expected.
The phenolic compound added as a contrast improver is preferably the following formulas (13), (14), (15), and (16), and is usually 1 to 20 parts by mass with respect to 100 parts by mass of the copolymer. Used in the amount of.

<Method for preparing photosensitive resin composition>
In preparing the photosensitive resin composition, each component including the component (A), the component (B), the component (C) and the component (D) may be blended together, or each component may be a solvent. You may mix | blend sequentially, after melt | dissolving in. In addition, there are no particular restrictions on the charging order and working conditions when blending.
For example, the resin composition may be prepared by dissolving all the components in a solvent at the same time, and if necessary, each component is appropriately made into two or more solutions, and these solutions are used at the time of use (at the time of application). You may mix and prepare as a photosensitive resin composition.

<Flat panel display and semiconductor device>
The flat panel display and semiconductor device of the present invention have a layer obtained by curing the photosensitive resin composition of the present invention, that is, a planarizing film or an interlayer insulating film. In forming the planarization film and the interlayer insulating film, a solution of the photosensitive resin composition is usually applied on the substrate and prebaked to form a coating film of the photosensitive resin composition. At this time, the substrate to which the photosensitive resin composition is applied may be any known substrate such as a conventional FPD substrate or a semiconductor device forming substrate such as glass or silicon. The substrate may be a bare substrate, may be formed with an oxide film, a nitride film, a metal film, or the like, or may be a substrate on which a circuit pattern or a semiconductor device is formed. Moreover, the temperature of prebaking is 40-140 degreeC normally, and time is about 0-15 minutes. Next, after pattern exposure is performed on the coating film through a predetermined mask, development processing is performed using an alkaline developer, and rinsing processing is performed as necessary to form a film of the photosensitive resin composition. The film thus formed is exposed to the entire surface and then post-baked to form a pattern film. The exposure amount for the entire surface exposure is usually 500 mJ / cm ² or more. The post-bake temperature is usually 150 to 250 ° C., preferably 180 to 230 ° C., and the post-bake time is usually 30 to 90 minutes.
The pattern film formed using the photosensitive resin composition is used as a flattening film or an interlayer insulating film of an FPD such as a semiconductor device, a liquid crystal display device, or a plasma display. When a pattern film is formed on the entire surface, pattern exposure, development, etc. need not be performed. Here, the planarizing film and the interlayer insulating film are not completely independent, and the pattern film formed of the photosensitive resin composition can be used as the planarizing film or the interlayer insulating film. In a semiconductor device or the like, such a film functions as both an interlayer insulating film and a planarizing film.
In the formation of the pattern film, as a method for applying the photosensitive resin composition, any method such as a spin coating method, a roll coating method, a land coating method, a spray method, a casting coating method, a dip coating method, and a slit coating method may be used. Use it. Examples of radiation used for exposure include ultraviolet rays such as g-rays, h-rays, and i-rays, far ultraviolet rays such as KrF excimer laser light or ArF excimer laser light, X-rays, and electron beams.
As a developing method, a method conventionally used for developing a photoresist, such as a paddle developing method, an immersion developing method, a swinging immersion developing method, or a shower type developing method may be used. Developers include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate and sodium silicate, organic amines such as ammonia, ethylamine, propylamine, diethylamine, diethylaminoethanol and triethylamine, and tetramethylammonium hydroxide. An aqueous solution in which a quaternary amine or the like is adjusted to a predetermined concentration can be used.

  Hereinafter, embodiments of the present invention will be described more specifically with reference to examples and comparative examples. “Part” and “%” are all based on mass unless otherwise specified. The measurement methods and evaluation methods used in the examples and comparative examples are shown below.

<Mass average molecular weight>
The mass average molecular weight (Mw) was measured with a RI detector using a gel permeation chromatography apparatus HLC-8220GPC manufactured by Tosoh Corporation, Tskel HZM-M manufactured by Tosoh Corporation as a column, and THF as an eluent. Thus, it was determined by conversion using a calibration curve obtained from a polystyrene standard having a known molecular weight.

[Synthesis Example 1-1, Synthesis of Copolymer A-1]
Into a 500 mL four-necked flask equipped with a thermometer, stirrer and condenser, 154.4 g of propylene glycol monomethyl ether acetate (PGMEA) was charged, and after nitrogen substitution, the temperature was raised to 85 ° C. with an oil bath. .
On the other hand, 20.0 g of dimethyl itaconate (DMI), 15.3 g of acrylic acid (AA), 64.7 g of methyl methacrylate (MMA), 4.0 g of azobisisobutyronitrile (AIBN) and 27.3 g of PGMEA were previously mixed uniformly. Was added at a constant rate from the dropping funnel over 2 hours, and then maintained at the same temperature for 8 hours to obtain a copolymer A-1.

[Synthesis Examples 1-2 to 7, Copolymer A-2 to 7]
A copolymer was synthesized in the same manner as in Synthesis Example 1-1 except that the charged species and amount described in Table 1 and the polymerization temperature were changed.
[Synthesis Examples 2-1 to 6, Copolymer A-8 to 13]
A copolymer was synthesized in the same manner as in Synthesis Example 1-1 except that the charged species and amount described in Table 2 and the polymerization temperature were changed.

[Comparative Synthesis Examples 1-2, Copolymer X-1-2]
A copolymer was synthesized in the same manner as in Synthesis Example 1-1 except that the charged species and amount described in Table 3 and the polymerization temperature were changed.

[Synthesis Example 3-1, Synthesis of Copolymer D-1]
Into a 500 mL four-necked flask equipped with a thermometer, a stirrer, and a condenser tube, 155.3 g of propylene glycol monomethyl ether acetate (PGMEA) was charged, purged with nitrogen, and then heated up to 90 ° C. in an oil bath. .
On the other hand, dimethyl itaconate (DMI) 12.7 g, methacrylic acid (MAA) 21.5 g, styrene (St) 47.3 g, hydroxypropyl methacrylate (HPMA) 18.5 g, t-butylperoxy-2-ethylhexano A solution prepared by uniformly mixing 3.0 g of ate (perbutyl O) and 27.4 g of PGMEA in advance (dropping component) was dropped at a constant rate from a dropping funnel over 2 hours, and then maintained at the same temperature for 8 hours. 1 was obtained.

[Synthesis Examples 3-2 to 10, Copolymer D-2 to 10]
A copolymer was synthesized in the same manner as in Synthesis Example 3-1, except that the preparation type and amount described in Table 4 and the polymerization temperature were changed.

[Comparative Synthesis Examples 3 to 10, Copolymers Y-1 to 8]
A copolymer was synthesized in the same manner as in Synthesis Example 3-1, except that the preparation type and amount described in Table 5 and the polymerization temperature were changed.

表１〜５における略号の意味は次の通りである。
ＤＭＩ：イタコン酸ジメチル
ＤＥＩ：イタコン酸ジエチル
ＤＢＩ：イタコン酸ジブチル
ＤｃＨＩ：イタコン酸ジシクロヘキシル
ＤｅＨＩ：イタコン酸ジエチルヘキシル
ＡＡ：アクリル酸
ＭＡＡ：メタクリル酸
ＭＭＡ：メタクリル酸メチル
ＢＭＡ：メタクリル酸ブチル
ＬＭＡ：メタクリル酸ラウリル
ＣＨＭＡ：メタクリル酸シクロヘキシル
ＤＣＰＭＡ：メタクリル酸ジシクロペンタニル
ＨＥＭＡ：メタクリル酸ヒドロキシエチル
ＨＰＭＡ：メタクリル酸ヒドロキシプロピル
ＡＩＢＮ：２，２’−アゾビスイソブチロニトリル〔アゾ系重合開始剤、和光純薬工業（株）製〕
Ｖ−６０１： 〔アゾ系重合開始剤、和光純薬工業（株）製〕
パーブチルＰＶ： 日油（株）製の過酸化物系重合開始剤
パーブチルＯ：ｔ−ブチルパーオキシ−２−エチルヘキサノエート、日油（株）製の過酸化物系重合開始剤
パーヘキシルＯ：ｔ−ヘキシルパーオキシ−２−エチルヘキサノエート、日油（株）製の過酸化物系重合開始剤
ＰＧＭＥＡ：プロピレングリコールモノメチルエーテルアセテート
ＥＤＭ：ジエチレングリコールメチルエチルエーテル

The meanings of the abbreviations in Tables 1 to 5 are as follows.
DMI: dimethyl itaconate DEI: diethyl itaconate DBI: dibutyl itaconate DcHI: dicyclohexyl itaconate DeHI: diethylhexyl itaconate AA: acrylic acid MAA: methacrylic acid MMA: methyl methacrylate BMA: butyl methacrylate LMA: lauryl methacrylate CHMA : Cyclohexyl methacrylate DCPMA: dicyclopentanyl methacrylate HEMA: hydroxyethyl methacrylate HPMA: hydroxypropyl methacrylate AIBN: 2,2′-azobisisobutyronitrile [azo polymerization initiator, Wako Pure Chemical Industries, Ltd. ) Made]
V-601: [Azo-based polymerization initiator, manufactured by Wako Pure Chemical Industries, Ltd.]
Perbutyl PV: Peroxide-based polymerization initiator manufactured by NOF Corporation Perbutyl O: t-butylperoxy-2-ethylhexanoate, Peroxide-based polymerization initiator manufactured by NOF Corporation Perhexyl O: t-hexylperoxy-2-ethylhexanoate, a peroxide polymerization initiator manufactured by NOF Corporation PGMEA: propylene glycol monomethyl ether acetate EDM: diethylene glycol methyl ethyl ether

<Example 1-1>
100.0 g of copolymer A-1 obtained in Synthesis Example 1-1 (333.3 g as a solution), a compound represented by the above formula (4) and 1, 25.0 g of esterified product with 2-naphthoquinonediazide-5-sulfonyl chloride, 40.0 g of EHPE-3150 [manufactured by Daicel Chemical Industries, Ltd.], 25 of the copolymer D-1 obtained in Synthesis Example 3-1. 0.0 g, CIP-210S (manufactured by San Apro Co., Ltd.) as a crosslinking accelerator, 2.0 g, a silicon-based surfactant for preventing radial wrinkles formed on the resist film during spin coating, so-called striation G-B1484 (manufactured by TEGO) was dissolved in an appropriate amount of propylene glycol monomethyl ether acetate (PGMEA) and stirred, and then filtered through a 0.2 μm filter. Te, to prepare a photosensitive resin composition.

(Formation of thin film pattern)
The photosensitive resin composition was spin-coated on a 6-inch silicon wafer and baked on a hot plate at 90 ° C. for 120 seconds to obtain a thin film (A) having a thickness of about 3.8 μm. The thin film was exposed to various line widths and contact hole test patterns having a line and space width of 1: 1 with an optimum exposure dose using an i-line stepper (FPA-2500i2) manufactured by Canon Inc. Development was performed at 23 ° C. for 80 seconds with a mass% tetramethylammonium hydroxide aqueous solution to obtain a thin film (B) in which a line & space pattern and a contact hole pattern having a line and space width of 1: 1 were formed. The thin film (B) was exposed on the entire surface by a proximity exposure apparatus (UX-1000SM-TW01) manufactured by Ushio Electric Co., Ltd., and then post-baked by heating at 230 ° C. for 30 minutes in an oven. A patterned thin film (pattern film) having a thickness of 0.0 μm was obtained.
(Evaluation of sensitivity)
The exposure amount (mJ / cm ² ) at which a line and space pattern with a line and space width of 1: 1 was obtained by the above method was evaluated as sensitivity.
(Evaluation of developability)
Among the patterns produced above, a 5 μm hole pattern was observed with a SEM (scanning electron microscope). The developability was evaluated as x when a residue was found on the entire surface of the hole portion, ○ when the residue was found only near the interface between the hole and the substrate, and ◎ when no residue was found on the entire surface of the hole portion.
(Evaluation of remaining film rate)
The residual film ratio was calculated from the following formula from the film thicknesses of the thin film (A) and the thin film (B) obtained by the above method.
Residual film ratio (%) = (thickness of thin film (B) (μm) / thickness of thin film (A) (μm)) × 100
(Evaluation of transmittance)
Using a non-alkali glass substrate having a size of 100 mm in length and 100 mm in width and performing the same operation as above except that the test pattern was not exposed with FPA-2500i2, a thin film without a pattern was obtained on the glass substrate. The transmittance of this thin film at 400 nm was measured using an ultraviolet-visible light spectrophotometer UV-2600 (manufactured by Shimadzu Corporation).
(Evaluation of foaming)
A pattern film having a film thickness of 2.0 μm, 4.0 μm, and 6.0 μm was formed by the method described above, and observed with an optical microscope (500 times). Foaming was observed at any film thickness. A case where foaming was observed only at 6.0 μm was evaluated as ◯, and a case where foaming was observed at 4.0 μm or less was evaluated as x.
(Evaluation of solvent resistance)
Using a non-alkali glass substrate having a size of 100 mm in length and 100 mm in width and performing the same operation as above except that the test pattern was not exposed with FPA-2500i2, a thin film without a pattern was obtained on the glass substrate. The thin film substrate was immersed in Remover N-321 (manufactured by Nagase ChemteX Corporation) at 40 ° C. for 30 minutes, rinsed with pure water, and re-baked at 200 ° C. for 15 minutes. The difference between the transmittance before immersion in the solvent and the transmittance difference after re-baking is less than 2%, the difference between 2 and 4% is ○, and the transmittance difference is more than 4%. As evaluated.

<Examples 1-2 to 7>
Example except using the copolymer of component (A), esterified product of component (B), epoxy compound of component (C), copolymer of component (D) and other additives shown in Table 6 The photosensitive resin composition was prepared by performing operation similar to 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

＜実施例２−１〜６＞
表７に示した成分（Ａ）の共重合体、成分（Ｂ）のエステル化物、成分（Ｃ）のエポキシ化合物、成分（Ｄ）の共重合体およびその他添加剤等を用いること以外は実施例１−１と同様の操作を行うことにより、感光性樹脂組成物を調製した。この感光性樹脂組成物について、実施例１−１と同様の物性を評価した。

<Examples 2-1 to 6>
Example except using the copolymer of component (A), esterified product of component (B), epoxy compound of component (C), copolymer of component (D) and other additives shown in Table 7 The photosensitive resin composition was prepared by performing operation similar to 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

＜実施例３−１〜１０＞
表８に示した成分（Ａ）の共重合体、成分（Ｂ）のエステル化物、成分（Ｃ）のエポキシ化合物、成分（Ｄ）の共重合体およびその他添加剤等を用いること以外は実施例１−１と同様の操作を行うことにより、感光性樹脂組成物を調製した。この感光性樹脂組成物について、実施例１−１と同様の物性を評価した。

<Examples 3-1 to 10>
Example other than using the copolymer of component (A), esterified product of component (B), epoxy compound of component (C), copolymer of component (D) and other additives shown in Table 8 The photosensitive resin composition was prepared by performing operation similar to 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

<Examples 4-1 to 8>
Examples other than using the copolymer of component (A), esterified product of component (B), epoxy compound of component (C), copolymer of component (D) and other additives shown in Table 9 The photosensitive resin composition was prepared by performing operation similar to 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

<Comparative Examples 1-16>
Other than using the copolymer of component (A), esterified product of component (B), epoxy compound of component (C), copolymer of component (D) and other additives shown in Table 10 and Table 11 Prepared the photosensitive resin composition by performing the same operation as Example 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

表６〜１１における略号の意味は次の通りである。
ＥＨＰＥ−３１５０：エポキシ樹脂（ダイセル化学工業（株）製）
ＣＰＩ−２１０ｓ：光酸発生剤（サンアプロ（株）製）
Ｇ−Ｂ１４８４：界面活性剤（大日本インキ化学工業（株）製）
Ｆ−４７７：界面活性剤（大日本インキ化学工業（株）製）
ＰＧＭＥＡ：プロピレングリコールモノメチルエーテルアセテート
ＥＤＭ：ジエチレングリコールメチルエチルエーテル

The meanings of the abbreviations in Tables 6 to 11 are as follows.
EHPE-3150: Epoxy resin (manufactured by Daicel Chemical Industries, Ltd.)
CPI-210s: Photoacid generator (manufactured by Sun Apro Co., Ltd.)
G-B1484: Surfactant (manufactured by Dainippon Ink & Chemicals, Inc.)
F-477: Surfactant (Dainippon Ink Chemical Co., Ltd.)
PGMEA: Propylene glycol monomethyl ether acetate EDM: Diethylene glycol methyl ethyl ether

From the results shown in Tables 6 to 9, in Examples 1-1 to 7, 2-1 to 6, 3-1 to 10 and 4-1 to 8, development residues are found in the development process for forming the pattern film. In addition, it was confirmed that foaming did not occur even in the formation of a thick film without impairing the film properties such as light transmittance and solvent resistance even after high temperature baking. In addition, although Examples 1-1-7, 2-1-6, 3-1-10, and 4-1-8 were not shown by Table 6-Table 9, the flatness of the pattern film was also favorable. .
On the other hand, in Comparative Examples-1 and 2, since the structural unit (a1) was not contained in the copolymer of component (A), the developability deteriorated. In Comparative Examples 3 to 10, since the copolymer of the component (D) was not a desired copolymer, the balance of the film density with the component (A) was lost and the foaming deteriorated. Further, in Comparative Examples 3 to 10, in addition to such foaming, the following problems were observed when the constituent components in the copolymer of the component (D) deviated from the constituent ratio. In Comparative Example-3, since the structural unit (d1) in the copolymer of the component (D) was excessively reduced, foaming deteriorated. In Comparative Example-4, since the structural unit (d1) in the copolymer of the component (D) was excessively contained, the developability deteriorated. In Comparative Example-5, the developability deteriorated because (d2) in the copolymer of component (D) was excessively reduced. In Comparative Example-6, the developability deteriorated because (d2) in the copolymer of component (D) was excessively contained. In Comparative Example-7, the developability deteriorated because (d3) in the copolymer of component (D) was excessively reduced. In Comparative Example-8, since (d3) in the copolymer of the component (D) was excessively contained, the remaining film ratio was lowered. In Comparative Example-9, since (d4) in the copolymer of component (D) was excessively reduced, developability deteriorated. In Comparative Example-10, since (d4) in the copolymer of component (D) was excessively contained, the transmittance was lowered. In Comparative Example-11, the addition amount of the component (B) was as small as 2 parts by mass, so the sensitivity and developability deteriorated. In Comparative Example-12, the transmittance decreased because the amount of component (B) added was excessive, 55 parts by mass. In Comparative Example-13, since the amount of component (C) added was as small as 5 parts by mass, solvent resistance was deteriorated. In Comparative Example-14, the added amount of component (C) was 80 parts by mass, so the transmittance was lowered. In Comparative Example-15, since the amount of component (D) added was as small as 5 parts by mass, foaming deteriorated. In Comparative Example-16, the sensitivity decreased because the amount of component (D) added was as large as 60 parts by mass.

Claims (5)

It contains component (A), component (B), component (C) and component (D), and the component ratio of each component is 5 to 50 parts by mass of component (B) with respect to 100 parts by mass of component (A). (C) A photosensitive resin composition having 10 to 70 parts by mass and component (D) 10 to 50 parts by mass,
The component (A) is a structural unit (a1) derived from an itaconic acid diester monomer represented by the following formula (1), and an α, β-unsaturated carboxylic acid single monomer represented by the following formula (2) An itaconic acid diester copolymer comprising a structural unit (a2) derived from a body and a structural unit (a3) derived from a (meth) acrylic acid ester monomer represented by the following formula (3):

(Wherein, R ¹ and R ² are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms).

(Wherein R ³ is a hydrogen atom or a methyl group)

(Wherein R ⁴ is a hydrogen atom or a methyl group, R ⁵ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon A hydroxyalkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms constituting the main ring)

Component (B) is an esterified product having a quinonediazide group obtained by esterifying a trifunctional phenolic compound represented by the following formula (4) and a quinonediazide compound represented by the following formula (4) ′. ,

(R ⁶ and R ⁷ represent hydrogen or SO ₂ X, and X represents a halogen. However, one of R ⁶ and R ⁷ always represents hydrogen, and one of R ⁶ and R ⁷ represents Always represents SO ₂ X)

Component (C) is a compound having two or more epoxy groups,
Component (D) is a structural unit derived from an itaconic acid diester monomer represented by the following formula (5), a structure derived from an aromatic vinyl monomer represented by the following formula (6) Unit (d2), structural unit (d3) derived from an α, β-unsaturated carboxylic acid monomer represented by the following formula (7) and (meth) acrylic acid ester represented by the following formula (8) A copolymer comprising a structural unit (d4) derived from a monomer, wherein the proportion of each structural unit in 100% by mass of the copolymer of component (D) is from 3 to 50 structural units (d1). Mass%, structural unit (d2) 20-70 mass%, structural unit (d3) 10-35 mass% and (d4) 3-55 mass%, and the total amount of (d1) and (d2) is 30-87. The photosensitive resin composition characterized by the above-mentioned.

(Wherein R ⁸ and R ⁹ are each independently a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms).

(Wherein R ¹⁰ and R ¹¹ are each independently a hydrogen atom or a methyl group)

(Wherein R ¹² is a hydrogen atom or a methyl group)

(In the formula, R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group, carbon A hydroxyalkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms constituting the main ring)   The proportion of each constituent unit in 100% by mass of the copolymer of component (A) is 2 to 50% by mass, (a2) 6 to 30% by mass, and (a3) 35 to 90% by mass, respectively. The photosensitive resin composition according to claim 1. As the structural unit (a3) in which the component (A) is derived from the (meth) acrylic acid ester monomer represented by the formula (3), R ⁵ is a linear alkyl group having 1 to 12 carbon atoms, At least one structural unit (a3X) selected from a branched alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, a benzyl group or an alicyclic hydrocarbon group having 3 to 12 carbon atoms in the main ring; 3. The photosensitive composition according to claim 1, wherein R ⁵ is an itaconic acid diester copolymer containing at least one structural unit (a3Y) selected from hydroxyalkyl groups having 1 to 12 carbon atoms. Resin composition.   The flat panel display which has a pattern film obtained from the photosensitive resin composition of any one of Claims 1-3.   The semiconductor device which has a pattern film obtained from the photosensitive resin composition of any one of Claims 1-3.