JP7322378B2 - Photosensitive resin composition, method for producing patterned cured film, cured product, interlayer insulating film, cover coat layer or surface protective film, and electronic component - Google Patents

Description

TECHNICAL FIELD The present invention relates to a photosensitive resin composition, a method for producing a patterned cured film, a cured product, an interlayer insulating film, a cover coat layer or a surface protective film, and an electronic component.

Conventionally, polyimide and polybenzoxazole, which have excellent heat resistance, electrical properties, mechanical properties, etc., have been used for surface protective films and interlayer insulating films of semiconductor devices. In recent years, a photosensitive resin composition obtained by imparting photosensitive properties to the resin itself has been used, and the use of this can simplify the production process of the pattern cured film and shorten the complicated production process.

Organic solvents such as N-methyl-2-pyrrolidone have been used in the development process in the production process of pattern cured films. A resin composition that can be developed with an alkaline aqueous solution has been proposed by a method of mixing a diazonaphthoquinone compound as a photosensitizer with a resin that is soluble in dimethylformamide (for example, Patent Documents 1 and 2).

In recent years, the miniaturization of transistors, which has supported the advancement of computer performance, is facing the limits of scaling laws. It is Under such circumstances, a three-dimensional package using TSV (Through Silicon Via), a 2.5-dimensional package using an interposer, or a 2.1-dimensional package have been proposed. The structure has attracted attention (for example, Non-Patent Document 1).

Among stacked device structures, multi-die fanout wafer level packaging is a package manufactured by encapsulating multiple dies in one package. It is attracting attention because it can be expected to be lower in cost and higher in performance than the conventional fan-out wafer level package, which is manufactured by sealing one die in a single package.

However, in manufacturing a multi-die fan-out wafer level package, from the viewpoint of protecting high-performance dies and sealing materials with low heat resistance and improving yields, it is not preferable to perform heat treatment at temperatures exceeding 200°C. For this reason, low-temperature curability is strongly required for alkali-soluble resins used as rewiring layers for rewiring copper (eg, Patent Document 3).

JP 2009-265520 A WO2014/115233 WO2008/111470 JP 2010-096927 A

"Semiconductor Technology Yearbook 2013 Packaging/Mounting", Nikkei Business Publications, Inc., December 2012, p. 41-50

In order to improve the low-temperature curability of the alkali-soluble resin, a cross-linking agent capable of cross-linking or polymerizing by heating (hereinafter sometimes referred to as "thermal cross-linking agent") is sometimes used. However, when such a thermal cross-linking agent is used, a polymerization reaction in which the thermal cross-linking agents condense with each other or between a resin and a thermal cross-linking agent may proceed even at room temperature. A problem arose that the storage stability deteriorated when stored at room temperature for a long period of time. This problem becomes significant in the case of a thermal cross-linking agent with a low reaction temperature.

In addition, although a conductor such as copper is used for rewiring of the above device, there is a tendency that the adhesiveness (adhesiveness) of the resin to the conductor wiring is insufficient. This poor adhesion is problematic in that it may cause disconnection or short circuit of the conductor wiring. Furthermore, conventional resins have the problem of being corrosive to metals such as copper. Patent Document 4 discloses that by adding a compound having an antirust effect, excellent adhesiveness can be exhibited without corroding copper. When a patterned resin film was prepared on a copper substrate and heat-cured, the problem of red discoloration at the opening also surfaced.

INDUSTRIAL APPLICABILITY The present invention is a photosensitive resin composition that exhibits excellent storage stability despite containing a thermal cross-linking agent, has high adhesion to substrates, and can produce cured films that are excellent in suppressing discoloration of copper substrates. An object of the present invention is to provide a photosensitive resin composition.

As a result of intensive studies by the present inventors, it was found that the storage stability of the photosensitive resin composition can be improved by combining two specific types of nitrogen-containing compounds with the photosensitive resin composition containing a thermal cross-linking agent. Further, the present inventors have found that a cured film obtained from the photosensitive resin composition has high adhesiveness to a substrate and can suppress discoloration of an opening on a copper substrate, thereby completing the present invention.
According to the present invention, the following photosensitive resin composition and the like are provided.
1. A photosensitive resin composition containing the following components (a) to (e).
(a) a polybenzoxazole precursor (b) a cross-linking agent that can be crosslinked or polymerized by heating (c) a photosensitizer (d) one or more compounds selected from the group consisting of a compound having a triazole ring and a compound having a tetrazole ring (e) one or more compounds selected from the group consisting of compounds having a pyridine ring and compounds having an imidazole ring2. The component (d) consists of 1,2,3-triazole and its derivatives, 1,2,4-triazole and its derivatives, 1,2,3-benzotriazole and its derivatives, and 1H-tetrazole and its derivatives. 2. The photosensitive resin composition according to 1, which is one or more compounds selected from the group.
3. 3. The photosensitive resin composition according to 1 or 2, wherein the component (e) is one or more compounds selected from the group consisting of pyridine and its derivatives, imidazole and its derivatives, and benzimidazole and its derivatives.
4. 4. The photosensitive resin composition according to any one of 1 to 3, wherein the content of component (d) is 0.3 parts by mass or more per 100 parts by mass of component (a).
5. 5. The photosensitive resin composition according to any one of 1 to 4, wherein the content of component (e) is 0.1 parts by mass or more per 100 parts by mass of component (a).
6. 6. The photosensitive resin composition according to any one of 1 to 5, wherein the content of component (b) is 5 parts by mass or more per 100 parts by mass of component (a).
7. 7. The photosensitive resin composition according to any one of 1 to 6, wherein the component (c) contains a diazonaphthoquinone compound.
8. A step of applying the photosensitive resin composition according to any one of 1 to 7 on a substrate and drying it to form a photosensitive resin film;
a step of pattern-exposing the photosensitive resin film to form a resin film;
forming a patterned resin film by developing the exposed resin film with an alkaline aqueous solution;
a step of heat-treating the patterned resin film to form a patterned cured film;
A method for producing a patterned cured film comprising:
9. A cured product obtained by curing the photosensitive resin composition according to any one of 1 to 7.
10. 9. The cured product according to 9, which is a pattern cured film.
11. An interlayer insulating film, a cover coat layer or a surface protective film produced using the cured product according to 9 or 10.
12. An electronic component having the interlayer insulating film, cover coat layer or surface protective film according to 11.

According to the present invention, a photosensitive resin composition that has excellent storage stability despite containing a thermal cross-linking agent, has high adhesion to a substrate, and has a cured film that is excellent in suppressing discoloration of a copper substrate. A manufacturable photosensitive resin composition can be provided.

FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; FIG. 10 is a schematic cross-sectional view explaining a manufacturing process of a fan-out package having a multilayer wiring structure; 1 is a schematic cross-sectional view of a fan-out package having an Under Bump Metal (UBM) free structure; FIG.

Hereinafter, embodiments of the photosensitive resin composition, method for producing a patterned cured film, cured product, interlayer insulating film, cover coat layer or surface protective film, and electronic component of the present invention will be described in detail. It should be noted that the present invention is not limited by the following embodiments.

As used herein, "A or B" may include either A or B, or may include both. In addition, the term "step" as used herein refers not only to an independent step, but also to the term if the desired action of the step is achieved even if it cannot be clearly distinguished from other steps. included. A numerical range indicated using "-" indicates a range including the numerical values before and after "-" as the minimum and maximum values, respectively. In addition, in the present specification, the content of each component in the photosensitive resin composition refers to the content of each component in the photosensitive resin composition, unless otherwise specified, when there are multiple substances corresponding to each component in the photosensitive resin composition. means the total amount of the substances present in the Further, unless otherwise specified, the exemplified materials may be used alone, or two or more of them may be used in combination. As used herein, room temperature refers to 23°C.

[Photosensitive resin composition]
The photosensitive resin composition of the present invention contains the following components (a) to (e).
(a) a polybenzoxazole precursor (b) a cross-linking agent that can be crosslinked or polymerized by heating (c) a photosensitizer (d) one or more compounds selected from the group consisting of a compound having a triazole ring and a compound having a tetrazole ring (e) one or more compounds selected from the group consisting of compounds having a pyridine ring and compounds having an imidazole ring It may be described as a component and (e) component. The photosensitive resin composition of the present invention is preferably a positive photosensitive resin composition.

Since the photosensitive resin composition of the present invention contains two specific nitrogen-containing compounds, namely component (d) and component (e), it has high storage stability despite containing component (b), and A cured film obtained from the photosensitive resin composition has high adhesiveness to a substrate and is also excellent in suppressing discoloration of the substrate.
Each component will be described below.

（式（ＩＩ）中、Ｕは４価の有機基であり、Ｖは２価の有機基である。）
式（ＩＩ）におけるヒドロキシ基を含有するアミドユニットは、加熱工程における脱水閉環により、その少なくとも一部が耐熱性、耐薬品性及び電気特性に優れるオキサゾール環に変換される。 ((a) component: polybenzoxazole precursor)
The polybenzoxazole precursor preferably has a structural unit represented by formula (II) below.

(In formula (II), U is a tetravalent organic group and V is a divalent organic group.)
At least a part of the hydroxy group-containing amide unit in formula (II) is converted to an oxazole ring having excellent heat resistance, chemical resistance and electrical properties by dehydration ring closure in the heating step.

Moreover, in the structural unit represented by formula (II), the amide unit containing a hydroxyl group is effective in improving the solubility of the polymer in an alkaline aqueous solution.

（式（ＩＩＩ）中、Ｕは４価の有機基であり、Ｖ及びＷは各々独立に２価の有機基である。ｊ及びｋはモル分率であり、ｊとｋの和は１００モル％であり、ｊが６０～９９．９モル％、ｋが０．１～４０モル％（好ましくはｊが８０～９９．９モル％、ｋが０．１～２０モル％）である。） A polymer having a structural unit represented by formula (II) may contain only one type of structural unit, or may contain two or more types of structural units. When the copolymer has two or more types of structural units, it is preferably a polymer having a structure represented by formula (III).

(In formula (III), U is a tetravalent organic group, V and W are each independently a divalent organic group, j and k are molar fractions, and the sum of j and k is 100 mol %, j is 60 to 99.9 mol% and k is 0.1 to 40 mol% (preferably j is 80 to 99.9 mol% and k is 0.1 to 20 mol%).

In formulas (II) and (III), the tetravalent organic group represented by U is the residue of diamines used in the synthesis of polyhydroxyamide. The tetravalent organic group represented by U is preferably a tetravalent aromatic group or an organic group having 6 to 40 carbon atoms, preferably a tetravalent aromatic group having 6 to 40 carbon atoms. more preferred. As the tetravalent aromatic group, one in which all four binding sites are present on the aromatic ring is preferred.
In addition, an aromatic group means a group containing an aromatic ring.

Diamines that give a tetravalent organic group represented by U include 3,3′-diamino-4,4′-dihydroxybiphenyl, 4,4′-diamino-3,3′-dihydroxybiphenyl, bis(3 -amino-4-hydroxyphenyl)propane, bis(4-amino-3-hydroxyphenyl)propane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3-hydroxyphenyl)sulfone, 2 , 2-bis(3-amino-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(4-amino-3-hydroxyphenyl)-1,1 , 1,3,3,3-hexafluoropropane and the like, but are not limited thereto.

The divalent organic group represented by W in formula (III) is the residue of diamines used in the synthesis of polyhydroxyamide. The divalent organic group represented by W is preferably a divalent aromatic group, a divalent aliphatic group, or an organic group having 4 to 20 carbon atoms, and an aromatic group having 4 to 20 carbon atoms. more preferably a group. The divalent organic group represented by W is a residue of diamines other than the diamines giving the tetravalent organic group represented by U.

Diamines giving a divalent organic group represented by W include 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, and 4,4'-diaminodiphenyl sulfide. , benzidine, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis(4-aminophenoxyphenyl)sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(4 -aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ether, 1,4-bis(4-aminophenoxy)benzene and other aromatic diamine compounds. In addition, as diamines having a silicone group, LP-7100, X-22-161AS, X-22-161A, X-22-161B, X-22-161C and X-22-161E (all are Shin-Etsu Chemical Co., Ltd. (manufactured by a company, trade name), etc., but are not limited to these.

In formulas (II) and (III), the divalent organic group represented by V is a residue of dicarboxylic acid or dicarboxylic acid derivative (hereinafter referred to as dicarboxylic acids) used in the synthesis of polyhydroxyamide. The divalent organic group represented by V is preferably a divalent aromatic group or an organic group having 6 to 40 carbon atoms.
From the viewpoint of heat resistance, it is preferably a divalent aromatic group having 6 to 40 carbon atoms, and the divalent aromatic group has two bonding sites on an aromatic ring. preferable.

From the viewpoint of having a high dehydration ring closure rate in a heating step at a low temperature (for example, 200 ° C. or less) and having good heat resistance and mechanical strength, V is a divalent organic group having an aliphatic structure with 6 to 30 carbon atoms. is preferably By using the component (a), in which V is a divalent organic group having an aliphatic structure with 6 to 30 carbon atoms, together with the component (b) described later, better mechanical properties, chemical resistance and heat resistance can be obtained. A pattern cured film having properties can be provided.

（式中、Ｚは各々独立に炭素数１～６の炭化水素基であり、ｉは１～６の整数である。） Dicarboxylic acids that give a divalent organic group represented by V include isophthalic acid, terephthalic acid, 2,2-bis(4-carboxyphenyl)-1,1,1,3,3,3-hexafluoropropane , 4,4′-dicarboxybiphenyl, 4,4′-dicarboxydiphenyl ether, 4,4′-dicarboxytetraphenylsilane, bis(4-carboxyphenyl)sulfone, 2,2-bis(p-carboxyphenyl) Aromatic dicarboxylic acids such as propane, 5-tert-butylisophthalic acid, 5-bromoisophthalic acid, 5-fluoroisophthalic acid, 5-chloroisophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid , 1,4-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, those having an aliphatic linear structure include malonic acid, dimethylmalonic acid, ethylmalonic acid, isopropylmalonic acid, di-n-butylmalonate acid, succinic acid, tetrafluorosuccinic acid, methylsuccinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, dimethylmethylsuccinic acid, glutaric acid, hexafluoroglutaric acid, 2-methylglutaric acid acid, 3-methylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, 3-ethyl-3-methylglutaric acid, adipic acid, octafluoroadipic acid, 3-methyladipic acid, pimelic acid , 2,2,6,6-tetramethylpimelic acid, suberic acid, dodecafluorosuberic acid, azelaic acid, sebacic acid, hexadecafluorosebacic acid, 1,9-nonanedioic acid, dodecanedioic acid, tridecanedioic acid , tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosanedioic acid, heneicosanedioic acid, docosanedioic acid, tricosanedioic acid, tetracosanedioic acid, pentacosanedioic acid, hexacosane diacid, heptacondioic acid, octacosanedioic acid, nonacosanedioic acid, triacontanedioic acid, hentriacontanedioic acid, dotriacontanedioic acid, diglycolic acid, and dicarboxylic acids represented by the following formulas. but not limited to these. These compounds can be used alone or in combination of two or more.

(Wherein, each Z is independently a hydrocarbon group having 1 to 6 carbon atoms, and i is an integer of 1 to 6.)

In the present invention, there are no particular restrictions on the method for producing component (a). Generally, it can be synthesized by using dicarboxylic acids, hydroxy group-containing diamines, and, if necessary, diamines other than hydroxy group-containing diamines. Specifically, it can be synthesized by converting a dicarboxylic acid derivative into a dihalide derivative and then reacting it with a diamine. A dichloride derivative is preferable as the dihalide derivative.

As a method for synthesizing the dichloride derivative, a dicarboxylic acid and a halogenating agent can be reacted in a solvent, or the reaction can be carried out in an excess amount of the halogenating agent and then the excess can be distilled off. As the halogenating agent, thionyl chloride, phosphoryl chloride, phosphorus oxychloride, phosphorus pentachloride, etc., which are commonly used in the acid chloride reaction of carboxylic acids, can be used. As the reaction solvent, N-methyl-2-pyrrolidone, N-methyl-2-pyridone, N,N-dimethylacetamide, N,N-dimethylformamide, toluene, benzene and the like can be used.

The amount of these halogenating agents used is preferably 1.5 to 3.0 mol, more preferably 1.7 to 2.5 mol, per 1.0 mol of the dicarboxylic acid derivative when the reaction is performed in a solvent. Preferably, when the reaction is carried out in a halogenating agent, it is preferably 4.0 to 50 mol, more preferably 5.0 to 20 mol. The reaction temperature is preferably -10 to 70°C, more preferably 0 to 20°C.

The reaction between the dichloride derivative and the diamines is preferably carried out in an organic solvent in the presence of a dehydrohalogenating agent. Organic bases such as pyridine and triethylamine can be used as dehydrohalogenating agents. Further, as an organic solvent, N-methyl-2-pyrrolidone, N-methyl-2-pyridone, N,N-dimethylacetamide, N,N-dimethylformamide, etc. can be used. The reaction temperature is preferably -10 to 30°C, more preferably 0 to 20°C.

Diamines include aromatic diamines, aliphatic diamines and cycloaliphatic diamines. Specifically, 2,5-diaminobenzoic acid, 3,4-diaminobenzoic acid, 3,5-diaminobenzoic acid, 2,5-diaminoterephthalic acid, bis(4-amino-3-carboxyphenyl)methylene, Bis(4-amino-3-carboxyphenyl) ether, 4,4'-diamino-3,3'-dicarboxybiphenyl, 4,4'-diamino-5,5'-dicarboxy-2,2'-dimethyl Biphenyl, 1,3-diamino-4-hydroxybenzene, 1,3-diamino-5-hydroxybenzene, 3,3'-diamino-4,4'-dihydroxybiphenyl, 4,4'-diamino-3,3' -dihydroxybiphenyl, bis(3-amino-4-hydroxyphenyl)propane, bis(4-amino-3-hydroxyphenyl)propane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3 -hydroxyphenyl)sulfone, bis(3-amino-4-hydroxyphenyl)ether, bis(4-amino-3-hydroxyphenyl)ether, bis(3-amino-4-hydroxyphenyl)hexafluoropropane, bis(4 -amino-3-hydroxyphenyl)hexafluoropropane, 1,4-diaminocyclohexane, 1,1,3,3,-tetramethyl 1,3-bis(4-aminophenyl)disiloxane, poly(propylene glycol)diamine etc., and these can be used alone or in combination of two or more.

Component (a) is usually developed with an alkaline aqueous solution. Therefore, it is preferably soluble in an alkaline aqueous solution. Examples of alkaline aqueous solutions include organic ammonium aqueous solutions such as tetramethylammonium hydroxide (TMAH) aqueous solutions, metal hydroxide aqueous solutions, and organic amine aqueous solutions.
In general, it is preferable to use a TMAH aqueous solution with a concentration of 2.38 mass %. Therefore, it is preferable that the component (a) is soluble in the TMAH aqueous solution.

One criterion for component (a) being soluble in an alkaline aqueous solution is described below. After dissolving the component (a) in an arbitrary solvent to form a solution, the solution is spin-coated on a substrate such as a silicon wafer to form a resin film having a thickness of about 5 μm. This is immersed in any one of a TMAH aqueous solution, a metal hydroxide aqueous solution, and an organic amine aqueous solution at 20 to 25°C. As a result, when dissolved to form a solution, the component (a) used is judged to be soluble in an alkaline aqueous solution.

The molecular weight of the component (a) soluble in an alkaline aqueous solution is preferably from 10,000 to 100,000, more preferably from 15,000 to 100,000, in terms of polystyrene weight average molecular weight. , 20,000 to 85,000. When the weight average molecular weight of component (a) is 10,000 or more, moderate solubility in an alkaline developer can be ensured. When the weight-average molecular weight of the component (a) is 100,000 or less, good solubility in solvents tends to be obtained, and it is possible to prevent the viscosity of the solution from increasing and the handleability from deteriorating.
The weight average molecular weight can be measured by gel permeation chromatography, and can be obtained by conversion using a standard polystyrene calibration curve.
Further, the degree of dispersion obtained by dividing the weight average molecular weight by the number average molecular weight is preferably 1.0 to 4.0, more preferably 1.0 to 3.5.

(Component (b): a cross-linking agent that can be cross-linked or polymerized by heating)
The crosslinking agent of the component (b) generally reacts (crosslinks) with the component (a) in the process of applying, exposing and developing the photosensitive resin composition, and then heat-treating the patterned resin film. The agent itself polymerizes.

（式（ＩＶ）中、Ｘは単結合又は１～４価の有機基であり、Ｒ^１１は水素原子又は１価の有機基であり、Ｒ^１２は１価の有機基である。ｌは１～４の整数であり、ｐは１～４の整数であり、ｑは０～３の整数である。ｌが２以上の場合、括弧内の基は同じでも異なってもよく、ｐが２以上の場合、括弧内の基は同じでも異なってもよく、ｑが２以上の場合、Ｒ^１２は同じでも異なってもよい。） Component (b) includes compounds represented by the following formulas (IV) to (VIII). The compounds represented by the following formulas (VI) and (VII) have a reaction temperature lower than that of other known thermal cross-linking agents, usually 150 to 250°C.

(In formula (IV), X is a single bond or a monovalent to tetravalent organic group, R ¹¹ is a hydrogen atom or a monovalent organic group, R ¹² is a monovalent organic group, l is 1 p is an integer of 1 to 4, q is an integer of 0 to 3. When l is 2 or more, the groups in parentheses may be the same or different, and p is 2 or more , the groups within the parentheses may be the same or different, and when q is 2 or more, R ¹² may be the same or different.)

（式（Ｖ）中、Ｙは各々独立に水素原子、炭素数１～１０のアルキル基、炭素数１～１０のアルキル基の水素原子の一部又は全部がフッ素原子で置換されたフルオロアルキル基、炭素数１～１０のアルキル基の水素原子の一部がヒドロキシル基で置換されたヒドロキシアルキル基、又は炭素数１～１０のアルコキシ基であり、Ｒ^１３及びＲ^１４は各々独立に１価の有機基であり、Ｒ^１５及びＲ^１６は各々独立に水素原子又は１価の有機基であり、ｒ及びｔは各々独立に１～３の整数であり、ｓ及びｕは各々独立に０～３の整数である。
ｒが２以上の場合、括弧内の基は同じでも異なってもよく、ｔが２以上の場合、括弧内の基は同じでも異なってもよく、ｓが２以上の場合、Ｒ^１３は同じでも異なってもよく、ｕが２以上の場合、Ｒ^１４は同じでも異なってもよい。）

(In formula (V), each Y is independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a fluoroalkyl group in which some or all of the hydrogen atoms of an alkyl group having 1 to 10 carbon atoms are substituted with fluorine atoms. , a hydroxyalkyl group in which some of the hydrogen atoms of an alkyl group having 1 to 10 carbon atoms are substituted with hydroxyl groups, or an alkoxy group having 1 to 10 carbon atoms, and R ¹³ and R ¹⁴ are each independently monovalent an organic group, each of R ¹⁵ and R ¹⁶ is independently a hydrogen atom or a monovalent organic group, each of r and t is independently an integer of 1 to 3, and each of s and u is independently 0 to 3; is an integer of
When r is 2 or more, the groups within the parentheses may be the same or different, when t is 2 or more, the groups within the parentheses may be the same or different, and when s is 2 or more, R ¹³ may be the same They may be different, and when u is 2 or more, R ¹⁴ may be the same or different. )

（式（ＶＩ）中、Ｒ^１７及びＲ^１８は各々独立に水素原子又は１価の有機基であり、２つのＲ^１８は互いが結合することで環構造となってもよい。）

（式（ＶＩＩ）中、Ｒ^１９～Ｒ^２４は各々独立に水素原子、メチロール基又はアルコキシメチル基（アルコキシ部分の炭素数は好ましくは１～４）である。） In formula (V), each Y is preferably independently a fluoroalkyl group in which part or all of the hydrogen atoms of an alkyl group having 1 to 4 carbon atoms are substituted with fluorine atoms. R ¹⁵ and R ¹⁶ are preferably hydrogen atoms. r and t are preferably two. s and u are preferably zero.

(In formula (VI), each of R ¹⁷ and R ¹⁸ is independently a hydrogen atom or a monovalent organic group, and two R ¹⁸ may combine to form a ring structure.)

(In formula (VII), R ¹⁹ to R ²⁴ are each independently a hydrogen atom, a methylol group or an alkoxymethyl group (the alkoxy moiety preferably has 1 to 4 carbon atoms).)

In formulas (IV) to (VI), the monovalent organic group includes an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxyalkyl group having 1 to 10 carbon atoms, and a hydroxyalkyl group having 1 to 10 carbon atoms. Preferred examples include 10 hydroxyalkoxy groups, or those in which some or all of the hydrogen atoms in these groups are substituted with halogen atoms. Examples of the monovalent to tetravalent organic group for X include the above monovalent organic groups and groups obtained by removing 1 to 3 hydrogen atoms from the above monovalent organic groups.

Among these, when the compounds represented by formulas (VI) and (VII) are used, when the photosensitive resin composition is cured at a low temperature of 200 ° C. or less, a cured film having excellent chemical resistance can be obtained. and from the viewpoint of cross-linking with the polymer.

（式中、Ｒ^２５、Ｒ^２６及びＲ^２８は、各々独立に水素原子又は炭素数１～２０（好ましくは炭素数１～１０又は１～５）のアルキル基であり、Ｒ^２７は、各々独立に水素原子又は炭素数１～１０のアルキル基である。） Specific examples of the compound represented by formula (VI) include compounds represented by the following formula.

(wherein R ²⁵ , R ²⁶ and R ²⁸ are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms (preferably 1 to 10 or 1 to 5 carbon atoms), and R ²⁷ is each independently is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)

More specific examples of the compounds represented by formulas (IV) and (V) include, but are not limited to, the following.

More specific examples of the compounds represented by formulas (VI) and (VII) include, but are not limited to, the following.

The content of component (b) in the photosensitive resin composition of the present invention is preferably 5 parts by mass or more, more preferably 5 to 40 parts by mass, more preferably 5 to 30 parts by mass per 100 parts by mass of component (a). Part by mass is more preferable.

((c) component: photosensitizer)
The photosensitizer of component (c) is a compound that generates an acid when irradiated with actinic rays, and has the function of increasing the solubility of the irradiated portion in an alkaline aqueous solution.

Examples of the photosensitive agent include diazonaphthoquinone compounds, aryldiazonium salts, diaryliodonium salts, triarylsulfonium salts, etc. Among them, diazonaphthoquinone compounds are preferred because of their high sensitivity.
The diazonaphthoquinone compound is a compound having a diazonaphthoquinone structure, and is preferably a compound containing a structure represented by the following formula (A) or (B).

A diazonaphthoquinone compound can be obtained, for example, by subjecting an o-quinonediazide sulfonyl chloride, a hydroxy compound, an amino compound, or the like to a condensation reaction in the presence of a dehydrochlorinating agent.

Examples of o-quinonediazide sulfonyl chlorides include 1,2-benzoquinone-2-diazide-4-sulfonyl chloride, 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and 1,2-naphthoquinone-2-diazide. -4-sulfonyl chloride and the like can be used.

Examples of hydroxy compounds include hydroquinone, resorcinol, pyrogallol, bisphenol A, bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,3,4,2',3'-pentahydroxybenzophenone, 2,3,4,3 ',4',5'-hexahydroxybenzophenone, bis(2,3,4-trihydroxyphenyl)methane, bis(2,3,4-trihydroxyphenyl)propane, 4b,5,9b,10-tetrahydro- 1,3,6,8-tetrahydroxy-5,10-dimethylindeno[2,1-a]indene, tris(4-hydroxyphenyl)methane, tris(4-hydroxyphenyl)ethane and the like can be used.

Examples of amino compounds include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, and 4,4'-diaminodiphenyl sulfide. , o-aminophenol, m-aminophenol, p-aminophenol, 3,3′-diamino-4,4′-dihydroxybiphenyl, 4,4′-diamino-3,3′-dihydroxybiphenyl, bis(3- amino-4-hydroxyphenyl)propane, bis(4-amino-3-hydroxyphenyl)propane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3-hydroxyphenyl)sulfone, bis( 3-amino-4-hydroxyphenyl)hexafluoropropane, bis(4-amino-3-hydroxyphenyl)hexafluoropropane and the like can be used.

（式（１１）中、Ｑは、各々独立に、水素原子又は下記式（１２）又は（１３）で表される基であり、複数のＱのうち少なくとも１つは下記式（１２）又は（１３）で表される基である。）

As the diazonaphthoquinone compound, a compound represented by the following formula (11) is preferable.

(In the formula (11), each Q is independently a hydrogen atom or a group represented by the following formula (12) or (13), and at least one of the plurality of Q is the following formula (12) or ( 13) is a group represented by

The content of component (c) in the photosensitive resin composition of the present invention is 0.01 to 50 parts by mass per 100 parts by mass of component (a) in order to improve sensitivity and resolution when exposed to light. parts, more preferably 0.1 to 30 parts by mass, even more preferably 0.5 to 25 parts by mass, and particularly preferably 3 to 20 parts by mass.

(Component (d): one or more compounds selected from the group consisting of compounds having a triazole ring and compounds having a tetrazole ring)
A compound having a triazole ring and/or a compound having a tetrazole ring is used as the component (d). Either one may be used alone, or both may be used in combination. By using the component (d), the adhesion (adhesion) between the cured film obtained from the photosensitive resin composition and the substrate (e.g., silicon substrate or copper substrate) can be improved, and the adhesion of the substrate (e.g., copper) can be improved. Corrosion can be prevented.

A "compound having a triazole ring" is a compound containing a triazole ring in its molecular structure, and includes a compound having a triazole ring as part of a condensed ring.
A "compound having a tetrazole ring" is a compound containing a tetrazole ring in its molecular structure, and also includes a compound having a tetrazole ring as part of a condensed ring.

Compounds having a triazole ring include 1,2,3-triazole and derivatives thereof, 1,2,4-triazole and derivatives thereof, and 1,2,3-benzotriazole (1H-benzotriazole) and derivatives thereof. mentioned.
Derivatives include compounds in which each compound is substituted with a substituent.

Examples of the above substituents include alkyl groups having 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms), aryl groups having 6 to 10 carbon atoms, alkoxy groups (the alkyl portion has 1 to 10 carbon atoms), and amino groups. , a nitro group, a mercapto group, an alkylthio group (the alkyl moiety has 1 to 5 carbon atoms), a carboxy group, a carbonyl group, a hydroxy group, etc., and compounds substituted with one or more of these may be used. .

Examples of compounds having a triazole ring include 1,2,4-triazole, 1,2,3-triazole, 3-mercapto-4-methyl-4H-1,2,4-triazole, 3-mercapto-1, 2,4-triazole, 4-amino-3,5-dimethyl-4H-1,2,4-triazole, 4-amino-3,5-dipropyl-4H-1,2,4-triazole, 3-amino- 5-isopropyl-1,2,4-triazole, 4-amino-3-mercapto-5-methyl-4H-1,2,4-triazole, 3-amino-5-mercapto-1,2,4-triazole, 3-amino-5-methyl-4H-1,2,4-triazole, 4-amino-1,2,4-triazole, 4-amino-3,5-dimethyl-1,2,4-triazole, 4- amino-5-methyl-4H-1,2,4-triazole-3-thiol, 3,5-diamino-1H-1,2,4-triazole, benzotriazole, 5-methyl-1H-benzotriazole, 5, Examples include, but are not limited to, 6-dimethylbenzotriazole, 5-amino-1H-benzotriazole, benzotriazole-4-sulfonic acid, and the like.

Compounds having a tetrazole ring include 1H-tetrazole and derivatives thereof. Examples of derivatives include compounds in which 1H-tetrazole is substituted with a substituent.

Examples of the above substituents include alkyl groups having 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms), aryl groups having 6 to 10 carbon atoms, alkoxy groups (the alkyl portion has 1 to 10 carbon atoms), and amino groups. , a nitro group, a mercapto group, an alkylthio group (the alkyl moiety has 1 to 5 carbon atoms), a carboxy group, a carbonyl group, a hydroxy group, etc., and compounds substituted with one or more of these may be used. .

Examples of compounds having a tetrazole ring include 1H-tetrazole, 5-methyl-1H-tetrazole, 5-(methylthio)-1H-tetrazole, 5-(ethylthio)-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 5-nitro-1H-tetrazole, 1-methyl-1H-tetrazole, 5,5′-bis-1H-tetrazole and the like, but are not limited thereto.

Component (d) includes 1,2,3-triazole and its derivatives, 1,2,4-triazole and its derivatives, 1,2,3-benzotriazole and its derivatives, 1H- Benzotriazole and its derivatives, 1H-benzotriazole and its derivatives having a substituent at the 6-position, 1H-benzotriazole and its derivatives having a substituent at the 5- and 6-positions, 1H-tetrazole and its derivatives, Substitution at the 5-position 1H-tetrazole and its derivatives having a group, and 1H-tetrazole and its derivatives having a substituent at the 1-position are preferred, 1H-benzotriazole, 5-methyl-1H-benzotriazole, 1H-tetrazole, 5-amino-1H -tetrazole, 5-methyl-1H-tetrazole, 5,5′-bis-1H-tetrazole are more preferred.

The content of component (d) in the photosensitive resin composition of the present invention is preferably 0.3 parts by mass or more, more preferably 0.3 to 30 parts by mass, more preferably 0.3 to 30 parts by mass per 100 parts by mass of component (a). 3 to 20 parts by weight, 0.3 to 10 parts by weight or 0.3 to 5 parts by weight is more preferable. Also, it may be 0.5 to 30 parts by weight, 1.0 to 20 parts by weight, or 2 to 20 parts by weight per 100 parts by weight of component (a).

(Component (e): one or more compounds selected from the group consisting of compounds having a pyridine ring and compounds having an imidazole ring)
A compound having a pyridine ring and/or a compound having an imidazole ring is used as the component (e). Either one may be used alone, or both may be used in combination.

Component (e) suppresses a polymerization reaction in which components (b) condense with each other or between components (a) and (b) when the photosensitive resin composition is stored in a liquid state at room temperature. As a result, the storage stability of the photosensitive resin composition can be improved, and even after long-term storage, good solubility and photosensitivity can be exhibited when the photosensitive resin film is exposed and developed. can be done. Furthermore, the component (e) improves the adhesion between a cured film obtained from the photosensitive resin composition and a substrate (for example, a silicon substrate or a copper substrate), and upon patterning on a substrate (for example, a copper substrate), Discoloration of the formed opening can be prevented.

A "compound having a pyridine ring" is a compound containing a pyridine ring in its molecular structure, and includes a compound having a pyridine ring as part of a condensed ring.
The “compound having an imidazole ring” is a compound containing an imidazole ring in its molecular structure, and includes compounds having an imidazole ring as part of condensed rings.

Examples of compounds having a pyridine ring include pyridine and derivatives thereof. Derivatives include, for example, compounds in which pyridine is substituted with a substituent.

Compounds having a pyridine ring include pyridine, 2-acetylpyridine, 3-acetylpyridine, 4-acetylpyridine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-(aminomethyl)pyridine, 3- (aminomethyl)pyridine, 4-(aminomethyl)pyridine, 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-hydroxypyridine, 3-hydroxypyridine, 4-hydroxypyridine, 2-phenylpyridine, 3 -phenylpyridine, 4-phenylpyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2,4-dimethylpyridine, 2,6-dimethylpyridine, 3,5-dimethylpyridine, 2,4,6 -trimethylpyridine, 2-mercaptopyridine, 3-mercaptopyridine, 4-mercaptopyridine and the like, but are not limited thereto.

Compounds having an imidazole ring include imidazole and its derivatives, benzimidazole and its derivatives, and the like. Examples of derivatives include compounds in which imidazole or benzimidazole is substituted with a substituent.

Examples of compounds having an imidazole ring include imidazole, 1-ethylimidazole, 2-ethylimidazole, 4-ethylimidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole, 2-phenyl-4-methylimidazole, benz imidazole, 1-methylbenzimidazole, 2-methylbenzimidazole, 2-mercaptobenzimidazole, 2-mercapto-1-methylimidazole, 2-mercapto-5-methylimidazole and the like, but are not limited thereto. do not have.

Among components (e), pyridine and derivatives thereof, pyridine and derivatives thereof having a substituent at the 3-position, pyridine and derivatives thereof having a substituent at the 4-position, imidazole and derivatives thereof, imidazole and derivatives thereof having a substituent at the 1-position and Derivatives thereof, imidazole and its derivatives having substituents at the 2- and 4-positions, benzimidazole and its derivatives are preferred, pyridine and its derivatives, 4-methylpyridine and its derivatives, imidazole and its derivatives, 1-methylimidazole and its Derivatives, 2-phenyl-4-methylimidazole and its derivatives, benzimidazole and its derivatives are more preferred.

The amount of component (e) blended in the photosensitive resin composition of the present invention is preferably 0.1 parts by mass or more, more preferably 0.1 to 30 parts by mass, more preferably 0.1 to 30 parts by mass per 100 parts by mass of component (a). 1 to 20 parts by mass or 0.1 to 15 parts by mass is more preferable.

(solvent)
The photosensitive resin composition of the invention usually contains a solvent.
Solvents include γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, benzyl acetate, n-butyl acetate, ethoxyethyl propionate, 3-methylmethoxypropionate, N-methyl-2-pyrrolidone, N, N -dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphorylamide, tetramethylenesulfone, cyclohexanone, cyclopentanone, diethyl ketone, diisobutyl ketone, methyl amyl ketone and the like. There is no particular limitation as long as it can sufficiently dissolve other components in the photosensitive resin composition.

Among these, γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, N-methyl-2-pyrrolidone, N,N-dimethylformamide, N , N-dimethylacetamide and dimethyl sulfoxide are preferably used.

The content of the solvent in the photosensitive resin composition of the present invention is not particularly limited, but is preferably 50 to 400 parts by mass, more preferably 100 to 300 parts by mass, more preferably 150 to 250 parts by mass based on 100 parts by mass of component (a). Parts by mass are more preferred.

The photosensitive resin composition of the present invention may optionally contain known coupling agents, dissolution accelerators, dissolution inhibitors, surfactants, leveling agents and the like in addition to the above components.

For example, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, 99.5% by mass or more, 99.9% by mass or more of the photosensitive resin composition of the present invention Alternatively, 100% by mass may be components (a) to (e) and the solvent.
The photosensitive resin composition of the present invention may consist essentially of components (a) to (e) and a solvent. In this case, it may contain unavoidable impurities.
Moreover, the photosensitive resin composition of the present invention may consist only of the components (a) to (e) and the solvent.

[Method for producing patterned cured film]
The method for producing a patterned cured film of the present invention comprises the steps of applying the above photosensitive resin composition on a substrate and drying it to form a photosensitive resin film, and pattern-exposing the photosensitive resin film to form a resin film. developing the exposed resin film with an alkaline aqueous solution to form a patterned resin film; and heating the patterned resin film to form a patterned cured film.
Each step will be described below.

(Photosensitive resin film forming step)
In this step, a photosensitive resin composition is applied onto a substrate and dried to form a photosensitive resin film.
Examples of substrates include glass, semiconductors, metal oxide insulators such as TiO ₂ and SiO ₂ , silicon nitride, copper, and copper alloys. The coating method is not particularly limited, but can be performed using a spinner or the like.

Drying can be performed using a hot plate, an oven, or the like. The heating temperature is preferably 100-150°C. The heating time is preferably 30 seconds to 5 minutes. Thereby, a photosensitive resin film can be obtained from the photosensitive resin composition.
The film thickness of the photosensitive resin film is preferably 5 to 100 μm, more preferably 8 to 50 μm, even more preferably 10 to 30 μm.

(Exposure process)
In this step, the photosensitive resin film is exposed in a pattern through a mask.
The actinic rays to be irradiated include ultraviolet rays including i-line, visible light, radiation, and the like, and i-line is preferable. As an exposure device, a parallel exposure machine, a projection exposure machine, a stepper, a scanner exposure machine, or the like can be used.

(Development process)
A patterned resin film (patterned resin film) can be obtained by developing the resin film that has undergone the exposure process. Generally, when a positive photosensitive resin composition is used, an exposed portion is removed with a developer.

An alkaline aqueous solution can be used as the developer, and examples of the alkaline aqueous solution include sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, tetramethylammonium hydroxide, etc. Tetramethylammonium hydroxide is preferred.
The concentration of the alkaline aqueous solution is preferably 0.1 to 10% by mass.

The development time varies depending on the type of polybenzoxazole precursor used, but is preferably 10 seconds to 15 minutes, more preferably 10 seconds to 5 minutes, and even more preferably 30 seconds to 4 minutes from the viewpoint of productivity.

Alcohols or surfactants may be added to the developer. The amount added is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the developer.

(Heat treatment step)
By heat-treating the patterned resin film, a crosslinked structure can be formed between the functional groups of the component (a) or between the components (a) and (b) to obtain a patterned cured film. In addition, the component (a) undergoes dehydration ring closure by the heat treatment step to give an oxazole ring.

The heating temperature is preferably 250°C or less, more preferably 120 to 250°C, even more preferably 160 to 230°C. Within this range, damage to substrates and devices can be minimized, devices can be produced with high yield, and energy saving in the process can be realized.

The heating time is preferably 5 hours or less, more preferably 30 minutes to 3 hours. Within this range, the cross-linking reaction or the dehydration ring-closing reaction can be allowed to proceed sufficiently. The atmosphere of the heat treatment may be the air or an inert atmosphere such as nitrogen, but the nitrogen atmosphere is preferable from the viewpoint of preventing the pattern resin film from being oxidized.

Devices used in the heat treatment process include quartz tube furnaces, hot plates, rapid thermal annealing, vertical diffusion furnaces, infrared curing furnaces, electron beam curing furnaces, microwave curing furnaces, and the like.

[Manufacturing process of semiconductor device]
Next, as an example of the method for producing a patterned cured film of the present invention, a process for producing a semiconductor device will be described with reference to the drawings. 1 to 7 are schematic cross-sectional views for explaining the manufacturing process of a fan-out package having a multilayer wiring structure, showing a series of processes from the first process to the seventh process. FIG. 8 is a schematic cross-sectional view of a fan-out package having a UBM (Under Bump Metal) free structure.

In these figures, a semiconductor substrate 1 such as a Si substrate having circuit elements (not shown) is covered with a protective film 2 such as a silicon oxide film except for predetermined portions of the circuit elements. A conductor layer 3 is formed.
A film of polyimide resin or the like is formed thereon as an interlayer insulating film 4 by spin coating or the like (first step, FIG. 1).

Next, a photosensitive resin layer 5 made of chlorinated rubber, phenol novolac, or the like is formed on the interlayer insulating film 4 by a spin coating method. A window 6A is provided as follows (second step, FIG. 2).

The interlayer insulating film 4 exposed in the window 6A portion is selectively etched by dry etching means using gas such as oxygen or carbon tetrafluoride to form the window 6B. Next, the photosensitive resin layer 5 is removed using an etching solution that corrodes the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed from the window 6B (third step, FIG. 3). ).

Further, using a known method, a second conductor layer 7 is formed and electrically connected to the first conductor layer 3 (fourth step, FIG. 4). When forming a multi-layer wiring structure of three or more layers, the above steps are repeated to form each layer.

Next, using the photosensitive resin composition of the present invention, a surface protection film 8 is formed as follows.
That is, the photosensitive resin composition of the present invention is applied by a spin coating method, dried, irradiated with light from a mask having a pattern for forming the window 6C in a predetermined portion, and then developed with an alkaline aqueous solution to form a pattern. A resin film is formed. Thereafter, this patterned resin film is heated to form a patterned cured film, that is, a surface protective film 8 (fifth step, FIG. 5). The surface protective film 8 has a function of protecting the conductor layer from external stress, α-rays, and the like.

Further, usually, after a metal thin film is formed on the surface of the surface protection film 8 by sputtering, a plating resist is formed in accordance with the window 6C using a known method, and the exposed metal thin film portion is plated to form a UBM. A metal layer 9 called (Under Bump Metal) is deposited. Then, the plating resist is removed, and the metal foil film other than the formation region of the metal layer 9 is removed by etching to form the UBM (sixth step, FIG. 6). Further, external connection terminals (bumps 10) called bumps are formed on the surface of the metal layer 9 (seventh step, FIG. 7). The metal layer 9 is formed for the purpose of relieving the stress acting on the bumps 10 and for the purpose of improving electrical connection reliability.

In recent years, from the viewpoint of manufacturing cost reduction, in order to omit the step of forming such a metal layer 9 (UBM), a UBM-free structure has been proposed in which the bumps 10 are formed directly after the windows 6C are formed in the surface protective film 8. It is In the UBM-free structure, it is preferable to form the second conductor layer 7 connected to the bump 10 thicker than usual in order to suppress an increase in electrical resistance due to the generation of intermetallic compounds. Furthermore, it is preferable that the stress acting on the bumps 10 is relieved by the surface protective film 8 . For this reason, it is preferable to form a thick surface protection film 8 in order to cover the thick second conductor layer 7 and increase the stress relaxation ability (FIG. 8). Therefore, in the UBM-free structure, when forming the window 6C in the surface protection film 8, it is preferable to apply a thicker resin film, expose it, and develop it.

[Cured product]
A cured product can be obtained by subjecting the photosensitive resin composition of the present invention to the above heat treatment step. The cured product of the present invention may be the above patterned cured film, or may be a cured product having no pattern.

[Electronic parts]
The electronic component of the present invention has the above-described patterned cured film or cured product, for example, a patterned cured film obtained by the above-described method for producing a patterned cured film.
Specifically, the pattern cured film or cured product can be used as a surface protective film for electronic parts, a cover coat layer, an interlayer insulating film, an interlayer insulating film for multilayer wiring boards, and the like.
Examples of electronic parts include semiconductor devices, multilayer wiring boards, and various electronic devices. Although the semiconductor device described above is one embodiment of the electronic component of the present invention, it is not limited to the above, and can have various structures.

Hereinafter, the present invention will be described more specifically based on examples and comparative examples. It should be noted that the present invention is not limited to the following examples.

Synthesis example 1
[Component (a): Synthesis of polybenzoxazole precursor]
Into a 0.2 liter flask equipped with a stirrer and a thermometer, 60 g of N-methyl-2-pyrrolidone was charged, and 13.92 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane ( 38 mmol) was added and dissolved with stirring. Subsequently, while maintaining the temperature at 0 to 5° C., 7.48 g (28 mmol) of dodecanedioic acid dichloride and 3.56 g (12 mmol) of 4,4′-diphenyletherdicarboxylic acid dichloride were added dropwise over 10 minutes. The solution was stirred for 60 minutes. The above solution was poured into 3 liters of water, the precipitate was recovered, washed with pure water three times, and then depressurized to obtain a polyhydroxyamide (polybenzoxazole precursor) (hereinafter referred to as polymer I). do). Polymer I had a weight average molecular weight of 33,100 and a dispersity of 2.0.

Synthesis example 2
[Component (a): Synthesis of polybenzoxazole precursor]
Into a 0.2 liter flask equipped with a stirrer and a thermometer, 60 g of N-methyl-2-pyrrolidone was charged, and 13.92 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane ( 38 mmol) was added and dissolved with stirring. Subsequently, 11.86 g (40 mmol) of 4,4′-diphenyletherdicarboxylic acid dichloride was added dropwise over 10 minutes while maintaining the temperature at 0 to 5° C., after which the temperature was returned to room temperature and the solution in the flask was stirred for 3 hours. The above solution was poured into 3 liters of water, the precipitate was recovered, washed with pure water three times, and then depressurized to obtain polyhydroxyamide (hereinafter referred to as polymer II). Polymer II had a weight average molecular weight of 22,400 and a dispersity of 3.2.

The weight average molecular weights of Polymers I and II were determined by gel permeation chromatography (GPC) standard polystyrene conversion.
The measurement conditions of the weight average molecular weight by the GPC method are as follows. Measurement was performed using a solution of 1 ml of solvent [tetrahydrofuran (THF)/dimethylformamide (DMF)=1/1 (volume ratio)] per 0.5 mg of polymer.
Measuring device: Detector L4000 manufactured by Hitachi, Ltd.
UV pump: L6000 manufactured by Hitachi, Ltd.
Shimadzu Corporation C-R4A Chromatopac
Measurement conditions: column Gelpack GL-S300MDT-5 × 2
Main eluent: THF/DMF = 1/1 (volume ratio)
LiBr (0.03 mol/l), _H3PO4 ( _0.06 mol/l)
Flow rate: 1.0 ml/min Detector: UV270 nm

Examples 1-12 and Comparative Examples 1-8
[Preparation of photosensitive resin composition]
Each component was mixed according to the components and blending amounts shown in Table 1 to prepare a photosensitive resin composition. The amounts shown in Table 1 are parts by mass of each component per 100 parts by mass of component (a). Each component used is as follows.

((a) component: polybenzoxazole precursor)
· a-1: Polymer I obtained in Synthesis Example 1
· a-2: Polymer II obtained in Synthesis Example 2

(Component (b): a cross-linking agent that can be cross-linked or polymerized by heating)
・ b-1: a compound represented by the following formula (manufactured by Allnex, trade name “Cymel 300”)

・ b-2: A compound represented by the following formula (manufactured by Sanwa Chemical Co., Ltd., trade name “Nikalac MX-270”)

((c) component: photosensitizer)
· c-1: a compound represented by the following formula (manufactured by Daito Chemix Co., Ltd., trade name "4C-PA280")

· c-2: a compound represented by the following formula (manufactured by Daito Chemix Co., Ltd., trade name "PA-28")

(Component (d): one or more compounds selected from the group consisting of compounds having a triazole ring and compounds having a tetrazole ring)
・ d-1: 1H-tetrazole (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ d-2: 5-amino-1H-tetrazole (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ d-3: 1H-benzotriazole (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)

(Component (e): one or more compounds selected from the group consisting of compounds having a pyridine ring and compounds having an imidazole ring)
・ e-1: pyridine (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ e-2: 4-methylpyridine (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ e-3: Imidazole (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ e-4: 1-methylimidazole (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ e-5: Benzimidazole (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ e-6: 2-phenyl-4-methylimidazole (manufactured by Shikoku Chemical Industry Co., Ltd., trade name “2P4MZ”)

尚、（ｅ’）成分とは、本発明で用いる（ｅ）成分とは異なる成分を意味する。 ((e') component)
・ e'-1: pyrrole (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ e'-2: N,N-diethylaniline (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)

The (e') component means a component different from the (e) component used in the present invention.

(solvent)
BLO (γ-butyrolactone)

[Production of patterned resin film]
The photosensitive resin composition immediately after preparation in [Preparation of photosensitive resin composition] (hereinafter sometimes referred to as "pre-storage photosensitive resin composition") is spin-coated on a silicon substrate and a copper substrate, and hot A photosensitive resin film of 11.0 to 11.5 μm (initial film thickness) was formed by heating on a plate at 110° C. for 3 minutes. The resulting photosensitive resin film was subjected to reduction projection exposure with i-line (wavelength: 365 nm) using an i-line stepper (manufactured by Canon Inc., trade name: "FPA-3000iW") and a mask. At this time, the amount of exposure was changed for each area, and a plurality of samples with different amounts of exposure were prepared. The exposed resin film was developed using a 2.38% aqueous solution of TMAH for a development time such that the film thickness after development was about 70 to 80% of the initial film thickness, to produce a patterned resin film. The film thickness of the obtained patterned resin film was measured.

In addition, after preparing in [Preparation of a photosensitive resin composition], a photosensitive resin composition (hereinafter sometimes referred to as a "photosensitive resin composition after storage") that has been stored at room temperature for 2 weeks. Operation was performed to produce a patterned resin film.

[Evaluation of storage stability (dissolution rate change in unexposed area)]
Regarding the patterned resin film on the silicon substrate obtained from the photosensitive resin composition before storage, the dissolution rate of the unexposed area and the amount of change in film thickness due to development (initial film thickness - film thickness after development) are calculated by development time. calculated by dividing Similarly, the dissolution rate of the unexposed area of the patterned resin film obtained from the photosensitive resin composition after storage was measured, and the dissolution rate of the photosensitive resin composition before storage was compared with the dissolution rate after storage based on the following formula. The rate of change in dissolution rate of the photosensitive resin composition was calculated. Table 1 shows the results.
Rate of change in dissolution rate (%) = {(dissolution rate (before storage) - dissolution rate (after storage)) / dissolution rate (before storage)} x 100
Based on the obtained absolute value of the rate of change in dissolution rate, evaluation was performed according to the following criteria.
A: The rate of change in dissolution rate (absolute value) is 0% or more and less than 10% B: The rate of change in dissolution rate (absolute value) is 10% or more and less than 30% C: The rate of change in dissolution rate (absolute value) is 30% that's all

[Production of pattern cured film]
For the patterned resin film on the copper substrate obtained from the photosensitive resin composition before storage obtained in [Production of patterned resin film], a vertical diffusion furnace μ-TF (manufactured by Koyo Thermo Systems Co., Ltd.) was used. After heating at 100° C. for 30 minutes in a nitrogen atmosphere, heat treatment was further performed at 200° C. for 1 hour to obtain a pattern cured film.

[Evaluation of Discoloration of Copper Substrate Opening]
The openings of the patterned cured film on the copper substrate obtained in [Production of patterned cured film] were observed and evaluated according to the following criteria. Table 1 shows the results.
A: No discoloration of opening B: Slightly reddish opening C: Severe discoloration of opening The results are shown in Table 1.

[Evaluation of adhesion (substrate adhesion grid number)]
[Preparation of photosensitive resin composition] The photosensitive resin composition immediately after preparation was spin-coated on a silicon substrate and a copper substrate, respectively, and heated at 110 ° C. for 3 minutes on a hot plate to obtain 11.0 to 11 A photosensitive resin film of 5 μm (initial film thickness) was formed. After that, a cured film was produced by the same operation as in [Production of patterned cured film], and the obtained cured film was subjected to adhesion between the substrate and the cured film according to the cross-cut method of JIS K 5600-5-6 standard. Characteristics were evaluated for each of the silicon substrate and the copper substrate based on the following criteria. Table 1 shows the results.
A: A cured film having a lattice number of 100 adhered to the substrate B: A cured film having a lattice number of 50 to 99 adhered to the substrate C: A cured film having a lattice number adhered to the substrate less than 50

From Table 1, the photosensitive resin composition of the present invention has excellent storage stability, and the cured film obtained from the photosensitive resin composition has high adhesion to silicon substrates and copper substrates, and has a discoloration suppressing effect. I know it's good.

The photosensitive resin composition of the present invention can be used for electronic parts such as semiconductor devices, multilayer wiring boards, and various electronic devices.

REFERENCE SIGNS LIST 1 semiconductor substrate 2 protective film 3 first conductor layer 4 interlayer insulating film 5 photosensitive resin layer 6A, 6B, 6C window 7 second conductor layer 8 surface protective film 9 metal layer 10 bump

Claims (12)

A photosensitive resin composition containing the following components (a) to (e).
(a) polybenzoxazole precursor (b) crosslinking agent capable of crosslinking or polymerizing by heating (c) photosensitive agent (d) 1,2,3-triazole and its derivatives, 1,2,3-benzotriazole and its derivatives , and one or more compounds selected from the group consisting of compounds having a tetrazole ring (e) one or more compounds selected from the group consisting of compounds having a pyridine ring and compounds having an imidazole ring (where imidazolyl group and alkoxy excluding imidazole silane compounds with silyl groups) The component (d) is one or more compounds selected from the group consisting of 1,2,3-triazole and its derivatives , 1,2,3-benzotriazole and its derivatives, and 1H-tetrazole and its derivatives. The photosensitive resin composition according to claim 1. 3. The photosensitive resin composition according to claim 1, wherein the component (e) is one or more compounds selected from the group consisting of pyridine and its derivatives, imidazole and its derivatives, and benzimidazole and its derivatives. 4. The photosensitive resin composition according to any one of claims 1 to 3, wherein the content of component (d) is 0.3 parts by mass or more per 100 parts by mass of component (a). The photosensitive resin composition according to any one of claims 1 to 4, wherein the content of component (e) is 0.1 parts by mass or more per 100 parts by mass of component (a). The photosensitive resin composition according to any one of claims 1 to 5, wherein the content of component (b) is 5 parts by mass or more per 100 parts by mass of component (a). The photosensitive resin composition according to any one of claims 1 to 6, wherein the component (c) contains a diazonaphthoquinone compound. A step of applying the photosensitive resin composition according to any one of claims 1 to 7 on a substrate and drying it to form a photosensitive resin film;
a step of pattern-exposing the photosensitive resin film to form a resin film;
forming a patterned resin film by developing the exposed resin film with an alkaline aqueous solution;
a step of heat-treating the patterned resin film to form a patterned cured film;
A method for producing a patterned cured film comprising: A cured product obtained by curing the photosensitive resin composition according to any one of claims 1 to 7. The cured product according to claim 9, which is a pattern cured film. An interlayer insulating film, a cover coat layer, or a surface protective film produced using the cured product according to claim 9 or 10. An electronic component comprising the interlayer insulating film, cover coat layer or surface protective film according to claim 11 .