JP2007186680A - Amide derivative, polymer, chemical amplification type photosensitive resin composition and method for forming pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a photosensitive resin composition having excellent resolution and developable with an alkali aqueous solution. <P>SOLUTION: The chemical amplification type photosensitive resin composition comprises a polymer containing at least one kind of a repeating structural unit represented by formula (2) (R<SP>2</SP>is a hydrogen atom or a group decomposable with an acid) and a photoacid generator. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a novel amide derivative, a polymer derived from the amide derivative, a chemically amplified photosensitive resin composition containing the polymer, and a pattern forming method using the composition. The present invention relates to an amide derivative, a polymer, a photosensitive resin composition, and a pattern forming method applicable to an interlayer insulating film and a surface protective film of a device.

  Conventionally, polyimide resins having excellent film characteristics such as heat resistance, mechanical characteristics, and electrical characteristics have been used for interlayer insulating films and surface protective films of semiconductor devices. However, when non-photosensitive polyimide resin is used as an interlayer insulation film, etc., positive resist is used in the pattern formation process, and etching and resist removal processes are required, which complicates the manufacturing process. Studies have been made on photosensitive polyimide resins having the following. As such a photosensitive polyimide resin composition, the positive photosensitive resin composition which consists of the polyimide acid described in patent document 1, an aromatic bisazide type compound, and an amine compound is mentioned. However, in the development process in the pattern forming process of the photosensitive polyimide resin, an organic solvent such as N-methyl-2-pyrrolidone or ethanol is required, which has been a problem in terms of safety and environmental impact.

  Therefore, in recent years, a positive photosensitive resin composition has been developed as a pattern forming material that can be developed with an alkaline aqueous solution such as a tetramethylammonium hydroxide (TMAH) aqueous solution used in a semiconductor fine pattern forming process. . For example, Patent Document 2 reports a non-chemically amplified positive photosensitive resin composition comprising a polybenzoxazole precursor and a diazoquinone compound as a photosensitizer. Non-Patent Document 1 reports a non-chemically amplified positive photosensitive resin composition comprising a polybenzoxazole precursor and 1,2-naphthoquinonediazide-5-sulfonic acid ester. Non-Patent Document 2 reports a chemically amplified positive photosensitive resin composition comprising a polybenzoxazole precursor protected with an acid-decomposable group and a photoacid generator.

  Such a photosensitive resin composition is excellent in heat resistance and electrical characteristics because the structure is changed by heat treatment and a benzoxazole ring is formed. For example, in the polybenzoxazole precursor described in Non-Patent Document 1, a benzoxazole ring is formed by heat treatment after alkali development, as shown in the following reaction formulas A1 and A2. Since the benzoxazole ring has a stable structure, interlayer insulating films and surface protective films using a photosensitive composition comprising this polybenzoxazole precursor have excellent film characteristics such as heat resistance, mechanical characteristics, and electrical characteristics. It will be a thing.

  In recent years, in the field of semiconductor device manufacturing, higher density and higher integration of devices and miniaturization of wiring patterns are required. Along with this, the demand for photosensitive resin compositions used for interlayer insulating films, surface protective films and the like has become stricter, but the positive photosensitive resin compositions described in the above-mentioned documents are in terms of resolution. Was not fully satisfactory.

  For this reason, development of the photosensitive resin composition which can perform alkali image development and can obtain high resolution, maintaining the conventional film | membrane characteristic is awaited.

Japanese Patent Publication No. 3-36861 Japanese Examined Patent Publication No. 1-46862 M.M. Ueda et al., Journal of Photopolymer Science and Technology, Vol. 16, No. 2, pages 237-242 (2003). K. Ebara et al., Journal of Photopolymer Science and Technology, Vol. 16, No. 2, pp. 287-292 (2003)

  The present invention has been made to solve the above problems, and a first object of the present invention is to provide an amide derivative and a polymer that can be preferably used as a raw material for a photosensitive resin composition. The second object is to provide a chemically amplified photosensitive resin composition that is excellent in film properties such as heat resistance, mechanical properties, and electrical properties, is capable of alkali development, and provides high resolution. The third object is to provide a pattern forming method using a chemically amplified photosensitive resin composition.

  As a result of investigations to achieve the above object, the present inventors have found that a polymer obtained by polymerizing a monomer composition containing an amide derivative having a specific structure, which is a novel compound, is a chemically amplified photosensitive resin composition. The present invention has been completed by finding that it is excellent as a product, can be developed with an alkaline aqueous solution, and has high resolution.

  That is, the present invention is an amide derivative represented by the following general formula (1).

(In the formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or a group decomposed by an acid, R ^{3 to} R ⁶ each independently represents a hydrogen atom, a halogen atom, or a carbon number of 1 to 4 alkyl groups or linked to each other to form a substituted or unsubstituted fused aromatic ring, but at least one fused aromatic ring is formed.)

  Moreover, this invention is a polymer containing 1 or more types of repeating structural units represented by following General formula (2) derived from the amide derivative represented by the said General formula (1).

(In Formula (2), R ¹ represents a hydrogen atom or a methyl group, R ² is a hydrogen atom or a group decomposed by an acid, R ^{3 to} R ⁶ are each independently a hydrogen atom, a halogen atom, or a carbon number of 1 to 4 alkyl groups or linked to each other to form a substituted or unsubstituted fused aromatic ring, but at least one fused aromatic ring is formed.)

  The polymer has at least one repeating structural unit represented by the general formula (2) and at least one repeating structural unit derived from a vinyl monomer copolymerizable with the structural unit.

  Furthermore, this invention is said polymer characterized by further including the structural unit represented by following General formula (3).

(In the formula, R ⁷ represents a hydrogen atom or a methyl group, and R ⁸ represents an organic group having a lactone structure.)

  The polymer preferably has a weight average molecular weight of 2,000 to 200,000.

  The present invention also provides a chemically amplified photosensitive resin composition comprising at least the above polymer and a photoacid generator.

  Furthermore, the present invention is the above chemically amplified photosensitive resin composition comprising a dissolution inhibitor and / or an adhesion improver.

  The dissolution inhibitor is a compound represented by the following general formula (4) or the following general formula (5).

(In the formula, R ⁹ and R ¹⁰ represent groups capable of decomposing by an acid, and R ¹¹ and R ¹² are linear, branched or cyclic alkyl groups or aromatic hydrocarbon groups having 1 to 10 carbon atoms. Z represents a direct bond, —C (CF ₃ ) ₂ —, —C (CH ₃ ) ₂ —, —SO ₂ —, —CO—, —O— or —CH ₂ —.

(Wherein R ¹³ represents a divalent aromatic hydrocarbon group or cycloaliphatic hydrocarbon group, R ¹⁴ and R ¹⁵ represent groups that are decomposed by an acid, and R ¹⁶ and R ¹⁷ represent a hydrogen atom, a halogen atom, or a carbon atom. Represents an alkyl group of formulas 1 to 4.)

  The adhesion improver is an organosilicon compound, and the organic compound is a compound represented by the following general formula (6).

(Wherein R ^{18 to} R ²³ represent a monovalent organic group, X ¹ and X ² represent a divalent organic group, and k is a positive integer.)

Furthermore, the present invention is a pattern forming method characterized by comprising at least the following steps:
Applying the chemical amplification type photosensitive resin composition on a substrate to be processed;
Performing pre-baking;
Exposure step;
Performing post-exposure baking;
A step of developing; and a step of post-baking.

  Further, the present invention is the pattern forming method described above, further comprising a post-exposure step between the developing step and the post-baking step.

  The amide derivative of the present invention can be preferably used as a raw material for producing a polymer, and this polymer can be preferably used for obtaining a chemically amplified photosensitive resin composition. In addition, the chemically amplified photosensitive resin composition and the pattern forming method of the present invention can be developed with an alkali developer, have excellent film properties such as heat resistance, mechanical properties, and electrical properties, and form high-resolution patterns. be able to.

  Furthermore, since the polymer of the present invention has a repeating structural unit represented by the general formula (2), it is stable by direct heat treatment or by heat treatment after decomposing an acid-decomposable group with an acid. An oxazole ring that is a structure can be formed.

  And since the oxazole ring is formed in the interlayer insulating film and the surface protective film using the chemically amplified photosensitive resin composition of the present invention containing this polymer by heat treatment, heat resistance, mechanical characteristics, electrical characteristics, etc. Excellent film characteristics.

  Hereinafter, the amide derivative, polymer, chemically amplified photosensitive resin composition and pattern forming method of the present invention will be described.

<Amide derivatives>
The amide derivative of the present invention is represented by the following general formula (1).

In formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or a group decomposed by an acid, R ^{3 to} R ⁶ each independently represents a hydrogen atom, a halogen atom, or a carbon number of 1 to 4. These alkyl groups, or linked to each other to form a substituted or unsubstituted fused aromatic ring, forms at least one fused aromatic ring.

  In addition, tert-butyl group, tetrahydropyran-2-yl group, tetrahydrofuran-2-yl group, 4-methoxytetrahydropyran-4-yl group, 1-ethoxyethyl group, 1-butoxyethyl are groups that can be decomposed by acid. Group, 1-propoxyethyl group, methoxymethyl group, ethoxymethyl group, tert-butoxycarbonyl group and the like.

Examples of the condensed aromatic ring formed by connecting R ^{3 to} R ⁶ to each other include a naphthalene ring, an anthracene ring, a phenanthrene ring, a phenalene ring, and a pyrene ring. The condensed aromatic ring thus formed may be substituted with a halogen atom or an alkyl group having 1 to 4 carbon atoms.

  Examples of the halogen atom include a fluorine atom and a chlorine atom.

  Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group.

Preferably, as the amide derivative represented by the general formula (1), the following general formula (1-1) in which two adjacent groups out of R ^{3 to} R ⁶ are bonded to form a naphthalene ring. Although the compound represented by-(1-3) is mentioned, it is not limited only to these.

(In the formula, R ^1, R ^2, the general formula (1) shows the same meaning as R ^1, R ^{2 in, R 3 ~R 6, R 24} ~R 35 each independently represent a hydrogen atom, Represents a halogen atom or an alkyl group having 1 to 4 carbon atoms.)

  More specifically, the following compounds may be mentioned, but the present invention is not limited to these.

   Polymers of these amide derivatives alone or with other copolymerizable monomers should be heat-treated after pattern formation and then heat-treated after acid-decomposable groups are decomposed with acid. Since a stable oxazole ring is formed, a film having excellent characteristics such as heat resistance, mechanical characteristics, and electrical characteristics can be formed.

Among the amide derivatives represented by the general formula (1), compounds in which R ^{1 to} R ⁴ are hydrogen atoms and R ⁵ and R ⁶ are connected to each other to form a naphthalene ring are, for example, 1-amino-2-naphthol It can be synthesized by reacting hydrochloride and acryloyl chloride in an aqueous sodium acetate solution.

<Polymer>
The polymer of the present invention contains at least one repeating structural unit represented by the following general formula (2).

In formula (2), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or a group decomposed by an acid, R ^{3 to} R ⁶ each independently represents a hydrogen atom, a halogen atom, or a carbon number of 1 to 4. These alkyl groups, or linked to each other to form a substituted or unsubstituted fused aromatic ring, forms at least one fused aromatic ring.

  Examples of groups that can be decomposed by an acid include t-butyl group, tetrahydropyran-2-yl group, tetrahydrofuran-2-yl group, 4-methoxytetrahydropyran-4-yl group, 1-ethoxyethyl group, 1-butoxyethyl group, Examples include 1-propoxyethyl group, methoxymethyl group, ethoxymethyl group, t-butoxycarbonyl group and the like.

Examples of the condensed aromatic ring formed by connecting R ^{3 to} R ⁶ to each other include a naphthalene ring and an anthracene ring. The condensed aromatic ring thus formed may be substituted with a halogen atom or an alkyl group having 1 to 4 carbon atoms.

  Examples of the halogen atom include a fluorine atom and a chlorine atom.

  Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group.

Preferably, as a repeating structural unit represented by the general formula (2), a general formula (2-1) in which two adjacent groups of R ^{3 to} R ⁶ are bonded to form a naphthalene ring as shown below. ) To (2-3), but not limited thereto.

(In the formula, R ^1, R ^2, the general formula (2) shows the same meaning as R ^1, R ^{2 in, R 3 ~R 6, R 24} ~R 35 each independently represent a hydrogen atom, Represents a halogen atom or an alkyl group having 1 to 4 carbon atoms.)

  More specifically, the following structural units may be mentioned, but the present invention is not limited to these.

  The polymer of the present invention can be heat-treated as it is, heat-treated after forming a pattern, or exposed again entirely after pattern formation, and heat-treated after decomposing acid-decomposable groups in the remaining pattern with an acid. Then, a ring closing reaction occurs and an oxazole ring is formed.

For example, in the formula (2-1), an amide polymer in which R ^{1 to} R ⁴ and R ^{24 to} R ²⁷ are hydrogen atoms undergoes a cyclization reaction by heat treatment as shown in the following reaction formula B. A naphthoxazole ring is formed. Even when R ² is an acid-decomposable group, a structure in which R ² is a hydrogen atom can be obtained by decomposing the acid-decomposable group with an acid.

  Since this naphthoxazole ring has a stable structure, the use of this polymer for an interlayer insulating film or a surface protective film makes it possible to use an interlayer insulating film or a surface protective film excellent in film characteristics such as heat resistance, mechanical characteristics and electrical characteristics. It is possible to form a film.

  The raw material of the polymer of the present invention is not particularly limited as long as it can synthesize a polymer containing one or more repeating structural units represented by the general formula (2), but the amide represented by the general formula (1) Derivatives can be preferably used.

  The polymer of the present invention is obtained by polymerizing a single amide derivative represented by the general formula (1) alone, or by copolymerizing two or more amide derivatives represented by the general formula (1). Although it may be obtained, it may be obtained by further copolymerization using a comonomer copolymerizable with the above amide derivative. The copolymer obtained by copolymerizing the amide derivative and the comonomer has the characteristics of the comonomer. Therefore, by using various comonomers, the chemically amplified photosensitive resin containing the polymer is used. Properties useful for the composition (resolution, sensitivity) and properties useful for interlayer insulating films and surface protective films formed of photosensitive resins (for example, heat resistance, mechanical properties, electrical properties, etc.) can be improved.

  As the comonomer, a vinyl monomer is preferable because it has sufficient polymerizability with the amide derivative. As the vinyl monomer, (meth) acrylamide derivatives other than the amide derivatives, butadiene, acrylonitrile, styrene, (meth) acrylic acid, ethylene derivatives, styrene derivatives, (meth) acrylic acid ester derivatives, and the like can be used.

  Examples of ethylene derivatives include ethylene, propylene, vinyl chloride, and examples of styrene derivatives include α-methylstyrene, p-hydroxystyrene, chlorostyrene, and styrene derivatives described in JP-A No. 2001-172315.

  In addition to vinyl monomers, maleic anhydride, N-phenylmaleimide derivatives and the like can be used. Examples of N-phenylmaleimide derivatives include N-phenylmaleimide and N- (4-methylphenyl) maleimide. . These comonomer can use 1 type (s) or 2 or more types.

  Specific examples of the structural unit derived from the comonomer of the above-described copolymer include a structural unit derived from a (meth) acrylic ester having a lactone structure represented by the following general formula (3).

(In the formula, R ⁷ represents a hydrogen atom or a methyl group, and R ⁸ represents an organic group having a lactone structure.)

  Examples of the repeating structural unit represented by the general formula (3) include, but are not limited to, the following examples.

  In order to exhibit excellent film characteristics when the polymer of the present invention is used for an interlayer insulating film or a surface protective film, the proportion of the repeating structural unit represented by the general formula (2) in the polymer is: 10-100 mol% is preferable and 40-100 mol% is more preferable.

  In addition, as a weight average molecular weight (Mw) of a polymer, 2,000-200,000 is preferable normally and 4,000-100,000 are more preferable. When the weight average molecular weight (Mw) of the polymer is less than 2,000, it may be difficult to form a film uniformly when the polymer is used for an interlayer insulating film or a surface protective film. Moreover, when the weight average molecular weight of a polymer exceeds 200,000, when using a polymer for an interlayer insulation film or a surface protective film, resolution may worsen.

  Such a polymer can be obtained by polymerizing a monomer composition containing the amide derivative by a commonly used polymerization method such as radical polymerization or anion polymerization.

  For example, when a polymer is obtained by radical polymerization, an appropriate radical polymerization initiator such as 2,2′-azobis (isobutyronitrile) is added to a dry tetrahydrofuran solution of the monomer composition, and then argon is added. The polymer can be polymerized by stirring at 50 to 70 ° C. for 0.5 to 24 hours in an inert gas atmosphere such as nitrogen or nitrogen.

<Chemically amplified photosensitive resin composition>
The chemically amplified photosensitive resin composition of the present invention contains at least a polymer containing a repeating structural unit represented by the general formula (2) and a photoacid generator. It can be prepared by mixing with an acid generator.

  When this chemically amplified photosensitive resin composition is subjected to pattern exposure with actinic radiation, which will be described later, an acid is generated from the photoacid generator constituting the chemically amplified photosensitive resin composition of the exposed portion, and an acid-decomposable group in the resin is generated. The acid-decomposable group undergoes a decomposition reaction. As a result, in the exposed area, the polymer of the present invention becomes soluble in an alkaline developer, and a difference in solubility (dissolution contrast) occurs between the exposed area and the unexposed area. Pattern formation using this chemically amplified photosensitive resin composition is performed utilizing the difference in solubility in such an alkali developer.

In the present invention, in order to constitute such a chemically amplified photosensitive resin composition, the polymer needs to have at least an acid-decomposable group. The acid-decomposable group is represented by R ^{2 in the} general formula (2). Or may be introduced into a structural unit other than the general formula (2). As for the structural unit which has an acid-decomposable group, 10 mol% or more is preferable in all the structural units, and 20 mol% or more is more preferable. Moreover, 100 mol% or less is preferable and 80 mol% or less is more preferable. Polymer in which R ² and a structural unit an acid-decomposable group of the general formula (2) structural units and R ² is a hydrogen (2) are preferred. In addition, even when a polymer having no acid-decomposable group is used to constitute the chemically amplified photosensitive resin composition of the present invention, a sufficient dissolution inhibitory effect can be obtained by adding a dissolution inhibitor. In some cases, such a resin composition may be used.

  The photoacid generator is preferably a photoacid generator that generates an acid upon irradiation with light used for exposure, and the mixture with the polymer of the present invention is sufficiently dissolved in an organic solvent, and the solution. As long as a uniform coating film can be formed by a film forming method such as spin coating, there is no particular limitation. Further, the photoacid generator may be used alone or in combination of two or more.

  As photoacid generators, triarylsulfonium salt derivatives, diaryliodonium salt derivatives, dialkylphenacylsulfonium salt derivatives, nitrobenzyl sulfonate derivatives, sulfonic acid esters of N-hydroxynaphthalimide, sulfonic acids of N-hydroxysuccinimide Examples include ester derivatives, but are not limited thereto.

  The content of the photoacid generator is 0. 0 with respect to the total of the polymer and the photoacid generator from the viewpoint of realizing sufficient sensitivity of the chemically amplified photosensitive resin composition and enabling good pattern formation. 2 mass% or more is preferable and 1 mass% or more is more preferable. On the other hand, it is preferably 30% by mass or less, more preferably 15% by mass or less, from the viewpoint of realizing formation of a uniform coating film and suppressing residue (scum) after development.

  When preparing the chemically amplified photosensitive resin composition of the present invention, an appropriate solvent is used as necessary. The solvent is not particularly limited as long as the chemical amplification type photosensitive resin composition can be sufficiently dissolved and the solution can be uniformly applied by a method such as spin coating. Specifically, γ-butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, 2-heptanone, 2-methoxybutyl acetate, 2-ethoxyethyl acetate, methyl pyruvate, ethyl pyruvate, 3 -Methyl methoxypropionate, ethyl 3-methoxypropionate, N-methyl-2-pyrrolidone (NMP), cyclohexanone, cyclopentanone, methyl isobutyl ketone (MIBK), ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol Monoethyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, etc. It is possible to use. These may be used alone or in admixture of two or more.

  Furthermore, if necessary, other components such as a dissolution accelerator, a dissolution inhibitor, an adhesion improver, a surfactant, a pigment, a stabilizer, a coating property improver, and a dye are added to a chemically amplified photosensitive resin. Compositions can also be prepared.

  For example, by adding a dissolution inhibitor to the chemically amplified photosensitive resin composition, dissolution of an unexposed portion of the photosensitive resin in an alkaline developer is suppressed. On the other hand, in the exposed area, the acid-decomposable group in the structure of the dissolution inhibitor is also decomposed by the action of the acid generated from the photoacid generator constituting the chemically amplified photosensitive resin composition, so that the solubility in an alkali developer is increased. Will increase. As a result, the dissolution contrast between the exposed portion and the unexposed portion is increased, and a fine pattern can be formed.

  When a dissolution inhibitor is added to the chemically amplified photosensitive resin composition, the content of the polymer and the photoacid generator is from the viewpoint of enabling good pattern formation of the chemically amplified photosensitive resin composition. 1 mass% or more is preferable with respect to the sum total, and 5 mass% or more is more preferable. On the other hand, in order to realize formation of a uniform coating film, the content is preferably 70% by mass or less, and more preferably 50% by mass or less.

  Specific examples of the dissolution inhibitor include compounds represented by the following general formula (4) or the following general formula (5), but are not limited thereto.

In the formula (4), R ⁹ and R ¹⁰ represent a group capable of decomposing by an acid, and R ¹¹ and R ¹² are linear, branched or cyclic alkyl groups or aromatic hydrocarbon groups having 1 to 10 carbon atoms. Z represents a direct bond, —C (CF ₃ ) ₂ —, —C (CH ₃ ) ₂ —, —SO ₂ —, —CO—, —O— or —CH ₂ —.

  Examples of groups that can be decomposed by acid include t-butyl group, tetrahydropyran-2-yl group, tetrahydrofuran-2-yl group, 4-methoxytetrahydropyran-4-yl group, 1-ethoxyethyl group, 1-butoxy group. Examples include an ethyl group, 1-propoxyethyl group, methoxymethyl group, ethoxymethyl group, t-butoxycarbonyl group and the like.

  Examples of the linear, branched or cyclic alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a butyl group, a cyclohexyl group, a norbornyl group, and a 5-norbornen-2-yl group. Examples of the aromatic hydrocarbon group include a phenyl group, a tolyl group, and a naphthyl group.

In the formula (5), R ¹³ represents a divalent aromatic hydrocarbon group or cycloaliphatic hydrocarbon group, R ¹⁴ and R ¹⁵ represent groups decomposed by an acid, R ¹⁶ and R ¹⁷ represent a hydrogen atom, a halogen atom Or an alkyl group having 1 to 4 carbon atoms.

  Examples of the divalent aromatic hydrocarbon group include a phenylene group and a naphthylene group. Examples of the divalent cycloaliphatic hydrocarbon group include a cyclohexanediyl group, a norbornenediyl group, an adamantanediyl group, and a norbornanediyl group.

  Examples of the group that can be decomposed by an acid include a t-butyl group, a tetrahydropyran-2-yl group, a tetrahydrofuran-2-yl group, a 4-methoxytetrahydropyran-4-yl group, a 1-ethoxyethyl group, and a 1-butoxyethyl group. 1-propoxyethyl group, methoxymethyl group, ethoxymethyl group, t-butoxycarbonyl group and the like.

  Examples of the halogen atom include a fluorine atom and a chlorine atom.

  Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group.

  Further, for example, by adding an adhesion improver made of an organosilicon compound to the chemically amplified photosensitive resin composition, the adhesion of the photosensitive resin onto the substrate can be improved.

  Examples of the organosilicon compound include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, vinyltriethoxysilane, the organosilicon compound described in Japanese Patent No. 3422703, or the following general formula (6). An organosilicon compound is mentioned. It is not limited only to these.

（式中、）

(In the formula)

In Formula (6), R ^{18 to} R ²³ represent a monovalent organic group, and X ¹ and X ² represent a divalent organic group. K is a positive integer.

  Examples of the monovalent organic group include alkyl groups such as methyl group, ethyl group, propyl group, and butyl group, and aryl groups such as phenyl group, tolyl group, and naphthyl group.

Examples of the divalent organic group represented by X ₁ and X ₂ include alkylene groups such as methylene group, ethylene group, propylene group and butylene group, arylene groups such as phenylene group, and a combination thereof. .

Specific examples of the monovalent organic group represented by R ¹⁸ and R ¹⁹ include a monovalent organic group having an imide bond (—N—C (═O) —) or an amide bond represented by the following structure. Groups. k is preferably 1.

  When an adhesion improver is added to the chemically amplified photosensitive resin composition, its content is based on the sum of the polymer and the photoacid generator from the viewpoint of enabling formation of a pattern with excellent adhesion. 0.1 mass% or more is preferable and 0.5 mass% or more is more preferable. In order to enable good resolution, the content is preferably 25% by mass or less, and more preferably 15% by mass or less.

  The chemically amplified photosensitive resin composition of the present invention is excellent in pattern resolution and can be developed with an alkaline developer, and the film made of the chemically amplified photosensitive resin composition of the present invention is heat resistant, mechanical Excellent film characteristics such as characteristics and electrical characteristics. Therefore, such a chemically amplified photosensitive resin composition can be suitably used for forming an interlayer insulating film or a surface protective film.

<Pattern formation method>
The pattern forming method of the present invention comprises at least a coating step, a pre-bake step, an exposure step, a post-exposure bake step, a development step and a post-bake step. In detail, the above-mentioned chemically amplified photosensitive resin composition is coated. A coating step for coating on a processed substrate, a pre-baking step for fixing the chemically amplified photosensitive resin composition coating film on the substrate to be processed, and an exposure step for selectively exposing the chemically amplified photosensitive resin composition coating film A post-exposure baking process for baking the chemically amplified photosensitive resin composition coating film after exposure, a developing process for forming a pattern by dissolving and removing the exposed portion of the chemically amplified photosensitive resin composition coating film, and a pattern It comprises at least a post-baking step of curing the formed chemically amplified photosensitive resin composition coating film. Furthermore, the pattern forming method of the present invention may include a post-exposure step between the development step and the post-bake step.

  The application step is a step of applying the chemically amplified photosensitive resin composition to a substrate to be processed, such as a silicon wafer or a ceramic substrate. As the coating method, spin coating using a spin coater, spray coating using a spray coater, dipping, printing, roll coating, or the like can be used.

  The pre-baking step is a step for drying the chemically amplified photosensitive resin composition applied on the substrate to be processed to remove the solvent and fixing the chemically amplified photosensitive resin composition coating on the substrate to be processed. It is. A prebaking process is normally performed at 60-150 degreeC.

  In the exposure step, the chemically amplified photosensitive resin composition coating film is selectively exposed through a photomask to generate an exposed portion and an unexposed portion, and a pattern on the photomask is chemically amplified photosensitive resin composition. It is the process of transferring to an object coating film. Actinic rays used for pattern exposure include ultraviolet rays, visible rays, excimer lasers, electron beams, X-rays, and the like, and actinic rays having a wavelength of 180 to 500 nm are preferable.

  The post-exposure baking step is a step of promoting the reaction between the acid generated by exposure and the acid-decomposable group of the polymer. The post-exposure bake step is usually performed at 60 to 150 ° C.

  The development step is a step of forming a pattern by dissolving and removing the exposed portion of the chemically amplified photosensitive resin composition coating film with an alkaline developer. By the exposure step described above, a difference in solubility (dissolution contrast) of the polymer with respect to the alkali developer between the exposed portion and the unexposed portion of the chemically amplified photosensitive resin composition coating film is generated. By using this dissolution contrast, the exposed portion of the chemically amplified photosensitive resin composition coating film is dissolved and removed, and a chemically amplified photosensitive resin composition coating film (hereinafter simply referred to as “pattern”) is formed. ") Is obtained. Examples of the alkaline developer include an aqueous solution of a quaternary ammonium base such as tetramethylammonium hydroxide (TMAH) and tetraethylammonium hydroxide, and an aqueous solution to which an appropriate amount of a water-soluble alcohol such as methanol or ethanol, a surfactant or the like is added. Can be used. As the developing method, paddle, dipping, spraying and the like are possible. After the development process, the formed pattern is rinsed with water.

  The post-bake process is a process in which the obtained pattern is subjected to heat treatment in the air or in an inert gas atmosphere, for example, a nitrogen atmosphere, to improve the adhesion between the pattern and the substrate to be processed, and to cure the pattern. . In this post-baking process, by heating the pattern formed of the chemically amplified photosensitive resin composition, the structure of the polymer constituting the chemically amplified photosensitive resin composition is changed (modified), and the oxazole ring is changed. Is formed and the pattern is cured. In this way, a pattern having excellent film properties such as heat resistance, mechanical properties, and electrical properties can be obtained. A post-baking process is normally performed at 100-380 degreeC. Further, the post-baking process may be performed in one stage or in multiple stages.

  The post-exposure process is a process of exposing the entire surface of the chemically amplified photosensitive resin composition coating film on which the pattern is formed, and promoting the curing of the pattern in the subsequent post-baking process. The actinic radiation used for the post-exposure may be the same as the actinic radiation used in the exposure step, and is preferably actinic radiation having a wavelength of 180 to 500 nm.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited only to these examples.

Example 1
An amide derivative having the following structure, that is, an amide derivative in which R ^{1 to} R ⁴ and R ^{24 to} R ²⁷ are hydrogen atoms in the general formula (1-1) was synthesized.

  30 g of 1-amino-2-naphthol hydrochloride was dispersed in 400 ml of water and cooled on ice. Thereto, 56.6 g of sodium acetate was added, and 34.692 g of acryloyl chloride was further added dropwise. After stirring at room temperature for 6 hours, the precipitated crystals are filtered off and washed with water. The crystals were dissolved in ethyl acetate and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was recrystallized from a mixed solvent of ethyl acetate / methanol to obtain 7.92 g of the desired product (yield 24%).

The measurement result of ¹ H-NMR (THF-d ₈ ) of the obtained compound was as follows: δ was 5.81 (1H, dd), 6.49 (1H, d), 6.70 ( 1H, dd), 7.19 (1H, d), 7.30-7.34 (1H, m), 7.43-7.47 (1H, m), 7.69 (1H, d), 7 .79 (1H, d), 7.89 (1H, d), 8.96 (1H, s), 9.70 (1H, br).

(Example 2)
An amide derivative having the following structure, that is, an amide derivative in which R ¹ , R ³ and R ⁴ are hydrogen atoms, R ² is an ethoxymethyl group, and R ^{24 to} R ²⁷ are hydrogen atoms in the general formula (1-1) did.

  5 g of the amide derivative obtained in Example 1 and 4.55 g of N, N-diisopropylethylamine were dissolved in 50 ml of N-methylpyrrolidone (NMP), and 2.66 g of chloromethyl ethyl ether was added thereto, followed by stirring at room temperature. Three days later, the mixture was poured into 500 ml of water, and the organic layer was extracted with 200 ml of ethyl acetate and washed with 0.2 N hydrochloric acid, brine, 3% aqueous sodium hydroxide solution and brine in this order. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure, and the residue was recrystallized from hexane / ethyl acetate to obtain 3.435 g of the desired product (yield 54%).

The measurement result of ¹ H-NMR (THF-d ₈ ) of the obtained compound was as follows: δ was 1.18 (3H, t), 3.71 (2H, q), 5.25 ( 2H, s), 5.76 (1H, dd), 6.44 (1H, d), 6.69 (1H, dd), 7.1-7.4 (3H, m), 7.64 (1H) , D), 7.71 (1H, d), 7.8 (1H, d), 9.05 (1H, br).

(Example 3)
An amide derivative having the following structure, that is, an amide derivative in which R ^{1 to} R ³ , R ⁶ , and R ^{28 to} R ³¹ are hydrogen atoms in the general formula (1-2) was synthesized.

  3-amino-2-naphthol (5 g) and lithium chloride (1.465 g) are dissolved in N-methyl-2-pyrrolidone (50 ml), and acryloyl chloride (2.985 g) is added dropwise thereto under ice cooling. After stirring for 6 hours under ice cooling, the reaction mixture is poured into water and the organic layer is extracted with 200 ml of ethyl acetate. The organic layer was washed with 0.2N hydrochloric acid and brine. After drying over magnesium sulfate, ethyl acetate was distilled off under reduced pressure, and the residue was separated and purified on a silica gel column (eluent: ethyl acetate / hexane = 2/1) to give 3.28 g of the desired product (yield 49 %).

Example 4
A polymer having the following structure, that is, a polymer having 100 mol% of structural units in which R ^{1 to} R ⁴ and R ^{24 to} R ²⁷ are hydrogen atoms in the general formula (2-1) was synthesized.

  4 g of the amide derivative obtained in Example 1 was dissolved in 20 ml of tetrahydrofuran, 0.062 g of 2,2'-azobis (isobutyronitrile) was added thereto, and the mixture was heated to reflux for 4 hours under an argon atmosphere. After allowing to cool, it was reprecipitated in 200 ml of diethyl ether, and the precipitated polymer was filtered off and purified again by reprecipitation to obtain 3.12 g of the desired polymer (yield 78%). Moreover, the weight average molecular weight (Mw) measured by GPC analysis was 26500 (polystyrene conversion), and dispersion degree (Mw / Mn) was 2.78.

(Example 5)
In the polymer having the following structure, that is, in the general formula (2-1), the structural unit in which R ^{1 to} R ⁴ and R ^{24 to} R ²⁷ are hydrogen atoms is 50 mol%, and in the general formula (2-1), A polymer having 50 mol% of structural units in which R ¹ , R ³ and R ⁴ are hydrogen atoms, R ² is an ethoxymethyl group, and R ^{24 to} R ²⁷ are hydrogen atoms was synthesized.

  3 g of the amide derivative obtained in Example 1 and 3.82 g of the amide derivative obtained in Example 2 were dissolved in 33 ml of tetrahydrofuran, and 0.092 g of 2,2′-azobis (isobutyronitrile) was added thereto, The mixture was heated to reflux for 4 hours under an argon atmosphere. After allowing to cool, it was reprecipitated in 500 ml of diethyl ether, and the precipitated polymer was filtered off and purified again by reprecipitation to obtain 4.77 g of the target polymer (yield 70%). Moreover, the weight average molecular weight (Mw) measured by GPC analysis was 29800 (polystyrene conversion), and dispersion degree (Mw / Mn) was 3.11.

(Example 6)
In the polymer of the following structure, that is, in the general formula (2-1), R ^{1 to} R ⁴ and R ^{24 to} R ²⁷ are 30 mol% of a structural unit, and in the general formula (2-1), R ¹ , R ³ , R ⁴ are hydrogen atoms, R ² is an ethoxymethyl group, R ^{24 to} R ²⁷ are 50 mol% of structural units and styrene-based structural units are 20 mol%. .

  3 g of the amide derivative obtained in Example 1, 6.36 g of the amide derivative obtained in Example 2 and 0.977 g of styrene were dissolved in 50 ml of tetrahydrofuran, and 2,2′-azobis (isobutyronitrile) 0 was added thereto. 154 g was added and heated to reflux for 4 hours under an argon atmosphere. After allowing to cool, it was reprecipitated in 500 ml of diethyl ether, and the precipitated polymer was filtered off and purified again by reprecipitation to obtain 8.68 g of the desired polymer (yield 84%). Moreover, the weight average molecular weight (Mw) measured by GPC analysis was 25600 (polystyrene conversion), and dispersion degree (Mw / Mn) was 2.88.

(Example 7)
In the polymer having the following structure, that is, in the general formula (2-1), the structural unit in which R ^{1 to} R ⁴ are hydrogen atoms and R ^{24 to} R ²⁷ are hydrogen atoms is 30 mol%, and the general formula (2- In 1), R ¹ , R ³ , R ⁴ are hydrogen atoms, R ² is an ethoxymethyl group, R ^{24 to} R ²⁷ are hydrogen atoms in 50 mol%, and in general formula (3), R ⁷ is A polymer having a hydrogen atom and a structural unit of 20 mol% based on 5-acryloyloxy-2,6-norbornanecarbolactone having R ⁸ of 2,6-norbornanecarbolactone was synthesized.

  Polymerization was conducted in the same manner as in Example 6 except that 1.95 g of 5-acryloyloxy-2,6-norbornanecarbolactone was used instead of 0.977 g of styrene (yield 87%). Moreover, the weight average molecular weight (Mw) measured by GPC analysis was 30500 (polystyrene conversion), and dispersion degree (Mw / Mn) was 2.67.

(Example 8)
In the polymer having the following structure, that is, in the general formula (2-2), the structural unit in which R ^{1 to} R ³ , R ⁶ and R ^{28 to} R ³¹ are hydrogen atoms is 50 mol%, and the general formula (2-1) ), A polymer having 50 mol% of structural units in which R ¹ , R ³ and R ⁴ are hydrogen atoms, R ² is an ethoxymethyl group, and R ^{24 to} R ²⁷ are hydrogen atoms was synthesized.

  Polymerization was carried out in the same manner as in Example 5 except that the amide derivative obtained in Example 3 was used instead of the amide derivative obtained in Example 1 (yield 82%). Moreover, the weight average molecular weight (Mw) measured by GPC analysis was 30800 (polystyrene conversion), and dispersion degree (Mw / Mn) was 3.04.

(Synthesis Example 1)
A dissolution inhibitor having the following structure, that is, a compound in which R ⁹ and R ¹⁰ are ethoxymethyl groups, R ¹¹ and R ¹² are phenyl groups, and Z is —C (CF ₃ ) ₂ — in the general formula (4) did.

  10 g of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane is dissolved in 60 ml of NMP, and 2.546 g of lithium chloride is added thereto, and the mixture is cooled with ice. 8.06 g of benzoyl chloride is added thereto, and the mixture is stirred at room temperature overnight under ice cooling for 1 hour. The reaction mixture was poured into 600 ml of water, and the deposited precipitate was filtered off and washed with water to obtain 12 g of 2,2-bis (3-benzamido-4-hydroxyphenyl) hexafluoropropane. Next, 10 g of 2,2-bis (3-benzamido-4-hydroxyphenyl) hexafluoropropane and 6.75 g of N, N-diisopropylethylamine were dissolved in 60 ml of NMP, and 3.62 g of chloromethyl ethyl ether was added thereto. Stir at room temperature. After 1 day, the mixture is poured into 600 ml of water, and the organic layer is extracted with 300 ml of diethyl ether and washed with 0.06N hydrochloric acid, brine, 3% aqueous sodium hydroxide, and brine in this order. After drying over magnesium sulfate, diethyl ether was distilled off under reduced pressure, and the residue was recrystallized from hexane / ethyl acetate (5/4) to obtain 7.8 g of the desired product (white solid, yield 65%).

The measurement result of ¹ H-NMR (THF-d ₈ ) of the obtained compound was as follows: δ was 1.22 (3H, t), 3.79 (2H, q), 5.39 ( 2H, s), 7.12 (1H, d), 7.27 (1H, d), 7.45-7.55 (3H, m), 7.9-7.93 (2H, m), 8 .73 (1H, s), 8.84 (1H, s).

(Synthesis Example 2)
Synthesis of a compound having the following structure (in the general formula (5), R ¹³ is a phenylene group, R ¹⁴ and R ¹⁵ are ethoxymethyl groups, and R ¹⁶ and R ¹⁷ are hydrogen atoms, the following formula)

  27.548 g of o-aminophenol and 11.484 g of lithium chloride are dissolved in 260 ml of N-methyl-2-pyrrolidone. Thereto, 25 g of isophthaloyl chloride is added under ice cooling, and the mixture is further stirred overnight at room temperature. The reaction mixture is poured into water and the deposited precipitate is filtered off and washed with water. Next, it is dissolved in 500 ml of tetrahydrofuran and dried over magnesium sulfate. The solvent was distilled off under reduced pressure to obtain 40 g of N, N′-di (2-hydroxyphenyl) isophthalamide. Next, 40 g of N, N′-di (2-hydroxyphenyl) isophthalamide and 44.52 g of N, N-dipropylethylamine were dissolved in 200 ml of N-methyl-2-pyrrolidone, and 23.88 g of chloromethyl ethyl ether was added thereto. And stirred at room temperature for 3 days. The reaction mixture is added to water and the organic layer is extracted with 300 ml of diethyl ether. The organic layer is washed with 0.06N hydrochloric acid, brine, 3% aqueous sodium hydroxide solution, brine in that order and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was recrystallized twice with hexane / ethyl acetate (1/1) to obtain 26 g of the desired compound (white solid, yield 49%).

¹ H-NMR (THF-d ₈ , δ value): 1.21 (12H, t), 3.78 (8H, q), 5.35 (8H, s), 6.99-7.08 (8H M), 7.24 (4H, dd), 7.64 (2H, s), 8.12 (4H, dd), 8.45 (4H, dd), 8.52 (2H, s), 9 .00 (2H, brs).

(Synthesis Example 3)
An organosilicon compound having the following structure (in the general formula (6), R ^{20 to} R ²³ are methyl groups, X ₁ and X ₂ are propylene groups, R ¹⁸ and R ¹⁹ are phenylmaleimide groups, and k is 1)

  8.389 g of 1,3-bis (3-aminopropyl) tetramethyldisiloxane was dissolved in 50 ml of NMP, and 10 g of phthalic anhydride was added dropwise thereto under ice cooling, followed by stirring at room temperature for 1 day. To the reaction mixture, 300 ml of ethyl acetate was added and washed with brine. After drying with magnesium sulfate, the solvent was distilled off under reduced pressure. Next, 18.389 g of the solidified residue was dissolved in 80 ml of acetic anhydride, and 8.309 g of sodium acetate was added thereto, and reacted at 90 ° C. for 5 hours. After cooling, the mixture was poured into ice water and stirred for 1 hour. The precipitated crystals were filtered off and washed with water. The obtained crystals were dissolved in 200 ml of ethyl acetate, washed with 5% sodium carbonate, brine and water in this order, and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and 150 ml of hexane was added to the residue and washed with stirring. Further, recrystallization from hexane / ethyl acetate (5/3) gave 8.68 g of the desired product (white solid, total yield 71%).

¹ H-NMR (THF-d ₈ , δ value): 0.81 (12H, s), 0.56-0.61 (4H, m), 1.67-1.75 (4H, m), 3 .6-3.65 (4H, m), 7.72-7.76 (4H, m), 7.78-7.82 (4H, m).

(Synthesis Example 4)
Organosilicon compound having the following structure (in the general formula (6), R ^{20 to} R ²³ are methyl groups, X ¹ and X ² are propylene groups, R ¹⁸ and R ¹⁹ are benzamide groups, and k is 1) A compound of the formula:

  7.467 g of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 9.71 g of N, N-dipropylethylamine were dissolved in 80 ml of tetrahydrofuran, and 8.87 g of benzoyl chloride was added dropwise thereto under ice-cooling. Stir at room temperature for 1 day. The reaction mixture is poured into water and the organic layer is extracted with 200 ml of diethyl ether. The organic layer was washed with 0.2N hydrochloric acid, brine, 3% aqueous sodium hydroxide, and brine in this order. After drying with magnesium sulfate, the solvent was distilled off under reduced pressure.

  The obtained object was a viscous liquid but solidified by leaving it in a refrigerator. The yield of the target product was 8 g (58% yield).

Example 9
A chemically amplified photosensitive resin composition having the following composition was prepared.
(A) Polymer obtained in Example 5: 4 g
(B) Photoacid generator (N- (p-toluenesulfonyloxy) naphthalimide, manufactured by Midori Chemical Co., Ltd., trade name: NAI-101): 0.096 g
(C) Dissolution inhibitor (Compound of Synthesis Example 1): 0.8 g
(D) Adhesion improver (Compound of Synthesis Example 3): 0.12 g
(D) γ-butyrolactone: 6 g

The above mixture was filtered using a 0.45 μm Teflon (registered trademark) filter to prepare a photosensitive resin composition. The photosensitive resin was spin-coated on a 5-inch silicon substrate and baked in an oven at 100 ° C. for 20 minutes to form a thin film having a thickness of 10 μm. Next, pattern exposure was performed with ultraviolet rays (wavelength λ = 350 to 450 nm) through a photomask. After the exposure, it is baked in an oven at 90 ° C. for 10 minutes, and then developed with a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution at room temperature for 3 minutes, followed by a rinse treatment with pure water for 2 minutes. Each was done. As a result, only the exposed portion of the photosensitive resin film was dissolved and removed in the developer, and a positive pattern was obtained. As a result of SEM observation of the obtained pattern, it was found that a 10 μm through-hole pattern could be resolved when exposed at an exposure amount of 700 mJ / cm ² . Next, the entire surface of the wafer on which the pattern is formed is exposed to ultraviolet rays (wavelength λ = 350 to 450 nm) at an exposure amount of 1000 mJ / cm ² , and further, under a nitrogen atmosphere, at 95 ° C. for 30 minutes and at 240 ° C. for 1 hour, respectively. By baking in an oven, a naphthoxazole ring was formed, and a final pattern excellent in heat resistance and the like having a cured film thickness of 8 μm was obtained. As a result of SEM observation of the formed pattern, no crack or peeling was observed in the pattern.

Similarly, the photosensitive resin compositions using the polymers obtained in Example 6, Example 7, and Example 8 were also evaluated. As a result, when the exposure amount was 600 mJ / cm ² , a 10 μm through-hole pattern could be resolved. Next, the entire surface of the wafer on which the pattern was formed was exposed to ultraviolet rays (wavelength λ = 350 to 450 nm) at an exposure amount of 1000 mJ / cm ² , and the obtained pattern was further heated at 95 ° C. for 30 minutes at 240 ° C. in a nitrogen atmosphere. Were baked in an oven for 1 hour to form a naphthoxazole ring, and a final pattern excellent in heat resistance and the like was obtained. As a result of SEM observation of the formed pattern, no crack or peeling was observed in the pattern.

(Example 10)
A chemically amplified photosensitive resin composition having the following composition was prepared.
(A) Polymer obtained in Example 8: 4 g
(B) Photoacid generator (N- (p-toluenesulfonyloxy) naphthalimide, manufactured by Midori Chemical Co., Ltd., trade name: NAI-101): 0.096 g
(C) Dissolution inhibitor (Compound of Synthesis Example 2): 1.2 g
(D) Adhesion improver (Compound of Synthesis Example 4): 0.12 g
(D) γ-butyrolactone: 6 g

The above mixture was filtered using a 0.45 μm Teflon (registered trademark) filter to prepare a photosensitive resin composition. The photosensitive resin was spin-coated on a 5-inch silicon substrate and baked in an oven at 100 ° C. for 20 minutes to form a thin film having a thickness of 10 μm. Next, pattern exposure was performed with ultraviolet rays (wavelength λ = 350 to 450 nm) through a photomask. After the exposure, it is baked in an oven at 90 ° C. for 10 minutes, and then developed with a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution at room temperature for 3 minutes, followed by a rinse treatment with pure water for 2 minutes. Each went. As a result, only the exposed portion of the photosensitive resin film was dissolved and removed in the developer, and a positive pattern was obtained. As a result of SEM observation of the obtained pattern, it was found that a 7 μm through-hole pattern could be resolved when exposed at an exposure amount of 700 mJ / cm ² . Next, the entire surface of the wafer on which the pattern is formed is exposed to ultraviolet rays (wavelength λ = 350 to 450 nm) at an exposure amount of 1000 mJ / cm ² , and further, under a nitrogen atmosphere, at 95 ° C. for 30 minutes and at 240 ° C. for 1 hour, respectively. By baking in an oven, a naphthoxazole ring was formed, and a final pattern excellent in heat resistance and the like having a cured film thickness of 8 μm was obtained. As a result of SEM observation of the formed pattern, no crack or peeling was observed in the pattern.

  As is apparent from the above description, in the photosensitive resin composition, by using a polymer obtained by polymerizing the polymer precursor containing the amide derivative of the present invention, development is possible with an aqueous alkali solution and resolution is achieved. A photosensitive resin composition having excellent properties can be obtained, and can be used as an interlayer insulating film or a surface protective film of a semiconductor element.

Claims (14)

Amide derivatives represented by the following general formula (1).

(In the formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or a group decomposed by an acid, R ^{3 to} R ⁶ each independently represents a hydrogen atom, a halogen atom, or a carbon number of 1 to 4 alkyl groups or linked to each other to form a substituted or unsubstituted fused aromatic ring, but at least one fused aromatic ring is formed.) The amide derivative according to claim 1, which is represented by the following general formula (1-1), (1-2) or (1-3).

(In the formula, R ^1, R ^2, the general formula (1) shows the same meaning as R ^1, R ^{2 in, R 3 ~R 6, R 24} ~R 35 each independently represent a hydrogen atom, Represents a halogen atom or an alkyl group having 1 to 4 carbon atoms.) A polymer containing one or more repeating structural units represented by the following general formula (2).

(In Formula (2), R ¹ represents a hydrogen atom or a methyl group, R ² is a hydrogen atom or a group decomposed by an acid, R ^{3 to} R ⁶ are each independently a hydrogen atom, a halogen atom, or a carbon number of 1 to 4 alkyl groups or linked to each other to form a substituted or unsubstituted condensed aromatic ring, which forms at least one condensed aromatic ring.) The repeating structural unit represented by the general formula (2) is a repeating structural unit represented by the following general formula (2-1), (2-2) or (2-3). Coalescence.

(In the formula, R ^1, R ^2, the general formula (2) shows the same meaning as R ^1, R ^{2 in, R 3 ~R 6, R 24} ~R 35 each independently represent a hydrogen atom, Represents a halogen atom or an alkyl group having 1 to 4 carbon atoms.)   The weight according to claim 3 or 4, comprising at least one repeating structural unit represented by the general formula (2) and at least one repeating structural unit derived from a vinyl monomer copolymerizable with the structural unit. Coalescence. The polymer according to claim 3 or 4, further comprising a structural unit represented by the following general formula (3).

(In the formula, R ⁷ represents a hydrogen atom or a methyl group, and R ⁸ represents an organic group having a lactone structure.)   The polymer according to any one of claims 3 to 6, wherein the polymer has a weight average molecular weight of 2,000 to 200,000.   A chemically amplified photosensitive resin composition comprising at least the polymer according to claim 3 and a photoacid generator.   The chemically amplified photosensitive resin composition according to claim 8, further comprising a dissolution inhibitor and / or an adhesion improver. 10. The chemically amplified photosensitive resin composition according to claim 9, wherein the dissolution inhibitor is a compound represented by the following general formula (4) or the following general formula (5).

(In the formula, R ⁹ and R ¹⁰ represent groups capable of decomposing by an acid, and R ¹¹ and R ¹² are linear, branched or cyclic alkyl groups or aromatic hydrocarbon groups having 1 to 10 carbon atoms. Z represents a direct bond, —C (CF ₃ ) ₂ —, —C (CH ₃ ) ₂ —, —SO ₂ —, —CO—, —O— or —CH ₂ —.

(Wherein R ¹³ represents a divalent aromatic hydrocarbon group or cycloaliphatic hydrocarbon group, R ¹⁴ and R ¹⁵ represent groups that are decomposed by an acid, and R ¹⁶ and R ¹⁷ represent a hydrogen atom, a halogen atom, or a carbon atom. Represents an alkyl group of formulas 1 to 4.)   10. The chemically amplified photosensitive resin composition according to claim 9, wherein the adhesion improver is an organosilicon compound. The chemically amplified photosensitive resin composition according to claim 11, wherein the organosilicon compound is a compound represented by the following general formula (6).

(Wherein R ^{18 to} R ²³ represent a monovalent organic group, X ¹ and X ² represent a divalent organic group, and k is a positive integer.) A pattern forming method comprising at least the following steps:
A step of applying the chemically amplified photosensitive resin composition according to any one of claims 8 to 12 on a substrate to be processed;
Performing pre-baking;
Exposure step;
Performing post-exposure baking;
A step of developing; and a step of post-baking.   The pattern forming method according to claim 13, further comprising a post-exposure step between the developing step and the post-baking step.