TWI890048B - Photosensitive resin composition and method for producing hardened relief pattern - Google Patents

Abstract

The present invention provides a negative photosensitive resin composition that achieves high copper adhesion and suppresses the formation of voids at the interface between the copper layer and the resin layer after high-temperature storage testing. The negative photosensitive resin composition of the present invention is characterized by comprising the following components: (A) at least one resin selected from (A1) a polyimide precursor and (A2) a polyimide, (B) a flavonoid represented by the following general formula (1), (C) a photopolymerization initiator, and (D) a solvent. (In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group.)

Description

Photosensitive resin composition and method for producing hardened relief pattern

The present invention relates to a photosensitive resin composition and a method for producing a hardened relief pattern.

Previously, polyimide resins and polybenzophenones with excellent heat resistance, electrical properties and mechanical properties were used in insulating materials for electronic parts and passivation films, surface protection films and interlayer insulating films of semiconductor devices. Among these resins, photosensitive resin compositions are widely used. They can be applied to easily form heat-resistant relief pattern films through coating, exposure, development, and curing via thermal imidization. These photosensitive resin compositions significantly reduce the number of steps required compared to conventional non-photosensitive materials.

On the other hand, in recent years, with the increasing integration and computing power, as well as the shrinking of chip size, the mounting methods (package structures) of semiconductor devices on printed circuit boards have also evolved. For example, previous mounting methods using metal pins and lead-tin eutectic soldering have evolved to structures such as BGA (ball grid array) and CSP (chip scale package), which enable higher-density mounting and utilize structures in which a polyimide film directly contacts the solder bumps. Furthermore, structures such as FO (fan-out) have been proposed, which include multiple redistribution layers on the surface of a semiconductor chip, each with an area larger than the semiconductor chip itself (see, for example, Patent Document 1).

Copper is commonly used for wiring in semiconductor devices. However, in large-area packages, the deterioration of electrical properties caused by the separation of copper from the interlayer insulating material due to stress generated by the difference in thermal expansion coefficients of dissimilar materials is particularly problematic. Therefore, the material used for the interlayer insulating film must have high adhesion to copper.

Furthermore, the application of semiconductor devices in automobiles and mobile phones has been extremely significant in recent years. Semiconductor devices in these fields are required to have high reliability, and reliability testing is performed in high-temperature environments.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] U.S. Patent No. 10658199

However, during the high-temperature storage test during the aforementioned reliability testing, a problem arose: after the test, voids formed at the interface between the copper layer and the resin layer, which had been connected via redistribution wiring. The formation of voids at the interface between the copper layer and the resin layer reduces the adhesion between the two.

The present invention was conceived in light of this existing practical situation. One of its objectives is to provide a negative photosensitive resin composition (hereinafter referred to as the "photosensitive resin composition" in this specification) that achieves high copper adhesion and, after high-temperature storage testing, suppresses the formation of voids at the interface between the copper layer and the resin layer. Another object of the present invention is to provide a method for forming a hardened relief pattern using the negative photosensitive resin composition of the present invention.

The inventors have discovered that the aforementioned problems can be solved by adding specific flavonoids to a photosensitive resin composition, leading to the completion of the present invention. Specifically, the present invention is as follows.

[1]

A negative photosensitive resin composition is characterized by comprising the following components: (A) at least one resin selected from (A1) a polyimide precursor and (A2) a polyimide, (B) at least one flavonoid represented by the following general formula (1) or (1-2),

(In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group.)

(C) Photopolymerization initiator, and (D) Solvent.

[2]

The negative photosensitive resin composition described in [1], wherein the above-mentioned flavonoid (B) is a compound represented by the following general formula (2).

(Where _n1 is an integer between 1 and 3, _n2 is 0 or 1, and _n3 is an integer between 1 and 2)

[3]

The negative photosensitive resin composition described in [2], wherein the above-mentioned flavonoid (B) is a compound represented by the following general formula (3).

(Where _n4 is 2 or 3, _n5 is 1 or 2)

[4]

The negative photosensitive resin composition described in [2], wherein the above-mentioned flavonoid (B) is a compound represented by the following general formula (4).

[Chemistry 5]

(where n ₄ is 2 or 3)

[5]

The negative photosensitive resin composition described in [1], wherein the flavonoid (B) is a compound represented by the following general formula (2-2).

(where _n2 is 0 or 1, and _R1 is an aromatic group having at least one hydroxyl group and may further have other substituents)

[6]

The negative photosensitive resin composition described in [5], wherein the above-mentioned flavonoid (B) is a compound represented by the following general formula (3-2).

(In the formula, _R1 is an aromatic group having at least one hydroxyl group and may further have other substituents)

[7]

The negative photosensitive resin composition according to any one of [1] to [6], wherein the polyimide precursor (A1) comprises a polyimide precursor having a structural unit represented by the following general formula (5):

{In formula (5), X ₁ is a tetravalent organic group, Y ₁ is a divalent organic group, n ₁ is an integer from 2 to 150, and R ₁₁ and R ₁₂ are each independently a hydrogen atom or a monovalent organic group}.

[8]

The negative photosensitive resin composition described in [7], wherein in the above general formula (5), at least one of R ₁₁ and R ₁₂ has a structural unit represented by the following general formula (6):

{In formula (6), L ₁ , L ₂ , and L ₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and m ₁ is an integer of 2 to 10}.

[9]

A negative photosensitive resin composition as described in any one of [1] to [8], wherein the negative photosensitive resin composition is a negative photosensitive resin composition for forming an interlayer insulating film.

[10]

A method for producing a hardened relief pattern comprises the following steps: (1) applying a negative photosensitive resin composition as described in any one of [1] to [9] on a substrate to form a photosensitive resin layer on the substrate; (2) exposing the photosensitive resin layer; (3) developing the exposed photosensitive resin layer to form a relief pattern; and (4) heating the relief pattern to form a hardened relief pattern.

[11]

As described in [10], the method for manufacturing a hardened relief pattern, wherein the heat treatment in the above step (4) is a heat treatment below 230°C.

[12]

A method for producing polyimide, comprising the step of hardening the negative photosensitive resin composition described in any one of [1] to [9].

The present invention provides a negative photosensitive resin composition that achieves high copper adhesion and suppresses the formation of voids at the interface between the copper layer and the resin layer after high-temperature storage testing. Furthermore, a method for forming a hardened relief pattern using the negative photosensitive resin composition is provided.

The following describes in detail a form for implementing the present invention (hereinafter referred to as the "present embodiment"). The present invention is not limited to the present embodiment and can be implemented with various modifications within the scope of its main principles. Furthermore, throughout this specification, when multiple structures represented by the same symbol in a general formula exist in a molecule, they may be the same or different.

<Negative photosensitive resin composition>

The negative photosensitive resin composition of this embodiment comprises the following components: (A) at least one resin selected from (A1) a polyimide precursor and (A2) a polyimide, (B) at least one flavonoid represented by the following general formula (1) or (1-2),

(In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group.)

(C) Photopolymerization initiator, and (D) Solvent.

(A)Resin (A1) Polyimide precursor

In this embodiment, the polyimide precursor (A1) is a resin component contained in the negative photosensitive resin composition and is converted to polyimide by applying a thermal cyclization treatment. The structure of the polyimide precursor (A1) is not limited as long as it is a resin suitable for use in a negative photosensitive resin composition, but it is preferably not alkali-soluble. By making the polyimide precursor not alkali-soluble, higher chemical resistance can be achieved.

The polyimide precursor is preferably a polyimide having a structure represented by the following general formula (5).

{In formula (5), X ₁ is a tetravalent organic group, Y ₁ is a divalent organic group, n ₁ is an integer from 2 to 150, and R ₁₁ and R ₁₂ are each independently a hydrogen atom or a monovalent organic group}

Preferably, in the general formula (5), at least one of R ₁₁ and R ₁₂ has a structural unit represented by the following general formula (6):

{In formula (6), L ₁ , L ₂ , and L ₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and m ₁ is an integer of 2 to 10}.

The ratio of hydrogen atoms in R ₁₁ and R ₁₂ in the general formula (5) is preferably 10% or less, more preferably 5% or less, and further preferably 1% or less, based on the total molar number of R ₁₁ and R _12. Furthermore, the ratio of monovalent organic groups represented by the general formula (6) in R ₁₁ and R ₁₂ in the general formula (5) is preferably 70% or more, more preferably 80% or more, and further preferably 90% or more, based on the total molar number of R ₁₁ and R _12. From the viewpoint of photosensitivity and storage stability, it is preferred that the ratio of hydrogen atoms and the ratio of organic groups in the general formula (6) are within the above ranges.

In the general formula (5), _n1 is not limited as long as it is an integer between 2 and 150. From the viewpoint of the photosensitivity and mechanical properties of the negative photosensitive resin composition, it is preferably an integer between 3 and 100, and more preferably an integer between 5 and 70.

In the general formula (5), the tetravalent organic group represented by _X1 is preferably an organic group having 6 to 40 carbon atoms, and more preferably an aromatic group or an alicyclic aliphatic group in which _{a -COOR11} group and a _-COOR12 group are adjacent to a -CONH- group. Specific examples of the tetravalent organic group represented by _X1 include, but are not limited to, an organic group having 6 to 40 carbon atoms and containing an aromatic ring, such as a group having a structure represented by the following general formula (20): [Chemical Formula 14]

{wherein, R6 is at least one selected from the group consisting of a hydrogen atom, a fluorine atom, a monovalent alkyl group having C1 to C10 carbon atoms, and a monovalent fluorine-containing alkyl group having C1 to C10 carbon atoms, 1 is an integer selected from 0 to 2, m is an integer selected from 0 to 3, and n is an integer selected from 0 to 4}. Furthermore, the structure of _X1 may be one or a combination of two or more. The _X1 group having the structure represented by formula (20) is particularly preferred from the viewpoint of having both heat resistance and photosensitivity.

As the _X1 group, among the structures represented by the above formula (20), the tetravalent organic group represented by the following formula is particularly preferred from the viewpoints of the imidization rate during low-temperature heating, degassing properties, copper adhesion, and chemical resistance:

{wherein, R6 is at least one selected from the group consisting of a fluorine atom, a monovalent alkyl group having 1 to 10 carbon atoms, and a monovalent fluorine-containing alkyl group having 1 to 10 carbon atoms, and m is an integer selected from 0 to 3}

In the general formula (5), the divalent organic group represented by _Y1 is preferably an aromatic group having 6 to 40 carbon atoms from the viewpoint of having both heat resistance and photosensitivity. For example, the structure represented by the following formula (21) can be cited, but is not limited thereto: [Chemical 16]

{wherein, R6 is at least one member selected from the group consisting of a hydrogen atom, a fluorine atom, a monovalent alkyl group having C1 to C10 carbon atoms, and a monovalent fluorine-containing alkyl group having C1 to C10 carbon atoms, and n is an integer selected from 0 to 4.} Furthermore, the structure of _Y1 may be a single member or a combination of two or more members. The _Y1 group having the structure represented by formula (21) is particularly preferred from the perspective of achieving both heat resistance and photosensitivity.

As the _Y1 group, among the structures represented by the above formula (21), the divalent group represented by the following formula is particularly preferred from the viewpoints of imidization rate during low-temperature heating, degassing properties, copper adhesion, and chemical resistance:

{wherein, R6 is at least one selected from the group consisting of a fluorine atom, a monovalent alkyl group having 1 to 10 carbon atoms, and a monovalent fluorine-containing alkyl group having 1 to 10 carbon atoms, and n is an integer selected from 0 to 4}

In the general formula (6), _L1 is preferably a hydrogen atom or a methyl group. _L2 and _L3 are preferably hydrogen atoms from the viewpoint of photosensitivity. _m1 is an integer from 2 to 10, preferably from 2 to 4, from the viewpoint of photosensitivity.

In one embodiment, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (7):

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

More preferably, in general formula (7), at least one of R ₁₁ and R ₁₂ is a monovalent organic group represented by general formula (6). By including the polyimide precursor (A1) represented by general formula (7), chemical resistance is particularly improved.

In one embodiment, from the viewpoint of thermal properties, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (8):

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

More preferably, in the general formula (8), at least one of R ₁₁ and R ₁₂ is a monovalent organic group represented by the general formula (6).

By making the polyimide precursor (A1) contain both the structural unit represented by the general formula (7) and the structural unit represented by the general formula (8), there is a tendency that the resolution is particularly improved. For example, the polyimide precursor (A1) may contain a copolymer of the structural unit represented by the general formula (7) and the structural unit represented by the general formula (8), or may be a mixture of the polyimide precursor represented by the general formula (7) and the polyimide precursor represented by the general formula (8).

In one embodiment, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (9): [Chemical 20]

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

In one embodiment, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (10):

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

By making the polyimide precursor (A1) contain a polyimide precursor represented by the general formula (10), chemical resistance is particularly improved.

In one embodiment, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (11):

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

By making the polyimide precursor (A1) contain the polyimide precursor represented by the general formula (11), Tg is particularly improved.

In one embodiment, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (12):

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

By making the polyimide precursor (A1) contain the polyimide precursor represented by the general formula (12), the dielectric constant is particularly improved.

In one embodiment, the polyimide precursor (A1) is preferably a polyimide precursor having a structural unit represented by the following general formula (13):

{wherein, R ₁₁ , R ₁₂ , and n ₁ are as defined above}.

By making the polyimide precursor (A1) contain the polyimide precursor represented by the general formula (13), the dielectric constant is particularly improved.

(A1) Preparation method of polyimide precursor

The polyimide precursor (A1) can be obtained by first reacting a tetracarboxylic dianhydride containing the aforementioned tetravalent organic group _X with a photopolymerizable alcohol having an unsaturated double bond and an optional alcohol not having an unsaturated double bond to prepare a partially esterified tetracarboxylic acid (hereinafter also referred to as an acid/ester). Subsequently, the partially esterified tetracarboxylic acid is subjected to amide condensation with a diamine containing the aforementioned _divalent organic group Y.

(Preparation of acid/ester)

In this embodiment, the tetracarboxylic dianhydride containing a tetravalent organic group _X1 which is preferably used to prepare the polyimide precursor (A1) is represented by the tetracarboxylic dianhydride represented by the above general formula (20), for example, pyromellitic dianhydride, diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride, benzophenone-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, diphenylsulfone-3,3',4,4'-tetracarboxylic dianhydride, diphenylmethane-3,3',4,4'-tetracarboxylic dianhydride, Examples of the preferred hydroxybenzoic acid dianhydride include, but are not limited to, 2,2-bis(3,4-phthalic anhydride)propane, 2,2-bis(3,4-phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane, and the like. Preferred examples include, but are not limited to, pyromellitic dianhydride, diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride, benzophenone-3,3',4,4'-tetracarboxylic dianhydride, and biphenyl-3,3',4,4'-tetracarboxylic dianhydride. These dianhydrides may be used alone or in combination of two or more.

In this embodiment, preferred photopolymerizable unsaturated double bond alcohols for preparing the polyimide precursor (A1) include 2-acryloyloxyethyl alcohol, 1-acryloyloxy-3-propyl alcohol, 2-acrylamidoethyl alcohol, hydroxymethyl vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-tert-butoxypropyl acrylate ... 2-Hydroxy-3-cyclohexyloxypropyl methacrylate, 2-methacryloyloxyethyl alcohol, 1-methacryloyloxy-3-propyl alcohol, 2-methacrylamidoethyl alcohol, hydroxymethyl vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-tert-butoxypropyl methacrylate, 2-hydroxy-3-cyclohexyloxypropyl methacrylate, etc.

The above-mentioned photopolymerizable alcohols with unsaturated double bonds may also be mixed with a portion of alcohols without unsaturated double bonds, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, neopentyl alcohol, 1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 3-octanol, 1-nonanol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, benzyl alcohol, etc.

Alternatively, a non-photosensitive polyimide precursor prepared solely from the aforementioned alcohols without unsaturated double bonds may be mixed with a photosensitive polyimide precursor for use as a polyimide precursor. From the perspective of resolution, the non-photosensitive polyimide precursor is preferably present in an amount of 200 parts by mass or less based on 100 parts by mass of the photosensitive polyimide precursor.

In the presence of an alkaline catalyst such as pyridine, the preferred tetracarboxylic dianhydride and the alcohol are dissolved in a solvent as described below at a temperature of 20-50°C and stirred for 4-24 hours. This allows the anhydride to undergo an esterification reaction to obtain the desired acid/ester.

(Preparation of polyimide precursor)

Under ice cooling, the acid/ester compound (typically, a solution in the following solvent) is added with a suitable dehydrating condensing agent, such as dicyclohexylcarbodiimide, 1-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, 1,1-carbonyldioxy-1,2,3-benzotriazole, N,N'-disuccinimidyl carbonate, etc., to convert the acid/ester compound into a polyanhydride. A diamine containing a divalent organic group _Y1 , preferably used in this embodiment, which is separately dissolved or dispersed in the solvent, is then dropwise added thereto to carry out amide condensation, thereby obtaining the target polyimide precursor. As an alternative method, the acid of the acid/ester is partially chlorinated using sulfinyl chloride or the like, and then reacted with a diamine compound in the presence of a base such as pyridine to obtain the target polyimide precursor.

The diamines containing a divalent organic group _Y1 preferably used in this embodiment are represented by diamines having a structure represented by the above-mentioned general formula (21), for example, p-phenylenediamine, m-phenylenediamine, 4,4-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone ...diphenyl sulfone, 3,4'-diaminodiphenyl '-Diaminobenzophenone, 3,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfonium, bis[4-(3-aminophenoxy)phenyl]sulfonium, 4,4-bis(4-aminophenoxy)biphenyl, 4,4-bis(3-aminophenoxy)biphenyl, Bis[4-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]ether, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 9,10-bis(4-aminophenyl)anthracene, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(3-aminopropyldimethylsilyl)benzene, o-toluidine, 9,9 -bis(4-aminophenyl)fluorene, and compounds in which a portion of the hydrogen atoms on the benzene ring are substituted with methyl, ethyl, hydroxymethyl, hydroxyethyl, halogen, etc., such as 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, and mixtures thereof, but not limited thereto.

After the amide polycondensation reaction is completed, the hygroscopic byproducts of the dehydrating condensation agent present in the reaction solution are filtered out as needed. A poor solvent such as water, aliphatic lower alcohol, or a mixture thereof is then added to the resulting polymer components to precipitate them. Repeated redissolution and reprecipitation operations are then performed to purify the polymer. The polymer is then vacuum-dried to isolate the target polyimide precursor. To further enhance the degree of purification, the polymer solution can be passed through a column filled with an anion and/or cation exchange resin swollen with a suitable organic solvent to remove ionic impurities.

The molecular weight of the polyimide precursor (A1), as measured by gel permeation chromatography (PCC) using a polystyrene-equivalent weight average molecular weight, is preferably 8,000 to 150,000, more preferably 9,000 to 50,000. A weight average molecular weight of 8,000 or greater provides excellent mechanical properties, while a weight average molecular weight of 150,000 or less provides good dispersibility in the developer and good relief pattern resolution. Tetrahydrofuran and N-methyl-2-pyrrolidone are recommended as developing solvents for gel permeation chromatography. The weight average molecular weight is determined based on a calibration curve prepared using standard monodisperse polystyrene. As a standard monodisperse polystyrene, we recommend choosing the organic solvent standard sample STANDARD SM-105 manufactured by Showa Denko.

(A2) Polyimide

The polyimide (A2) used in this embodiment is described. The resin component in the photosensitive resin composition is a polyimide resin having a structural unit represented by the following general formula (24).

{wherein, X ₂ is a tetravalent organic group having 6 to 40 carbon atoms, Y ₂ is a divalent organic group having 6 to 40 carbon atoms, and n is an integer from 2 to 50}

The resin represented by general formula (24) does not require chemical changes during the heat treatment step in order to exhibit sufficient membrane properties, and is therefore particularly suitable for treatment at lower temperatures.

In the general formula (24), the divalent organic group represented by X ₂ and/or the tetravalent organic group represented by Y ₂ preferably contains an aromatic ring structure, and more preferably contains a benzene ring structure, from the viewpoint of heat resistance.

From the viewpoint of solubility in an organic solvent, it is preferred that at least one of X ₂ and Y ₂ is a group containing a fluorine atom, and it is further preferred that both X ₂ and Y ₂ are groups containing a fluorine atom.

In general formula (24), the _tetravalent organic group represented by X and/or the _divalent organic group represented by Y preferably has a structure in which 2 to 6 benzene rings are linked via a single bond or a divalent linking group. Examples of the divalent linking group include an alkylene group, a fluorinated alkylene group, and an ether group. The alkylene group and the fluorinated alkylene group may be linear or branched.

(A2) Polyimide can be obtained by reacting a tetracarboxylic acid, its corresponding tetracarboxylic dianhydride, a tetracarboxylic diester dichloride, etc., with a diamine, its corresponding diisocyanate compound, trimethylsilyl diamine, etc. Polyimide can generally be obtained by dehydrating and ring-closing a polyamide, one of the polyimide precursors, obtained by reacting tetracarboxylic dianhydride with a diamine, by heating or chemical treatment with an acid or base.

Preferred tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3'-benzophenonetetracarboxylic dianhydride, 2,2-bis( 3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl) Sulfur dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 9,9-bis(3,4-dicarboxyphenyl)fluoric acid dianhydride, 9,9-bis{4-(3,4-dicarboxyphenoxy)phenyl}fluoric acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10- Aromatic tetracarboxylic dianhydrides such as perylenetetracarboxylic dianhydride, diphenylmethane-3,3',4,4'-tetracarboxylic dianhydride, and 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride; aliphatic tetracarboxylic dianhydrides such as butanetetracarboxylic dianhydride and 1,2,3,4-cyclopentanetetracarboxylic dianhydride; and compounds represented by 3,3',4,4'-diphenylsulfoniumtetracarboxylic dianhydride.

Among these, pyromellitic dianhydride (PMDA), diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride (ODPA), benzophenone-3,3',4,4'-tetracarboxylic dianhydride (BTDA), biphenyl-3,3',4,4'-tetracarboxylic dianhydride (BPDA), 3,3',4,4'-diphenylsulfonate-tetracarboxylic dianhydride (DSDA), diphenylmethane-3,3',4,4'-tetracarboxylic dianhydride, 2,2-bis(3,4-phthalic anhydride)propane, and 2,2-bis(3,4-phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane (6FDA) are preferred. These can be used alone or in combination of two or more.

Preferred diamines include 3,4'-diaminodiphenyl ether (3,4'-ODA), 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB), 3,3',5,5'-tetramethylbenzidine, 2,3,5,6-tetramethyl-1,4-phenylenediamine, 3,3'-diaminodiphenylsulfone, 3,3'-dimethylbenzidine, 3,3'-bis(trifluoromethyl) Benzidine, 2,2'-bis(p-aminophenyl)hexafluoropropane, bis(trifluoromethoxy)benzidine (TFMOB), 2,2'-bis(pentafluoroethoxy)benzidine (TFEOB), 2,2'-trifluoromethyl-4,4'-oxydiphenylamine (OBABTF), 2-phenyl-2-trifluoromethyl-bis(p-aminophenyl)methane, 2-phenyl-2-trifluoromethyl-bis(m-aminophenyl)methane 、2,2'-bis(2-heptafluoroisopropoxy-tetrafluoroethoxy)benzidine (DFPOB), 2,2-bis(m-aminophenyl)hexafluoropropane (6-FmDA), 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane, 3,6-bis(trifluoromethyl)-1,4-diaminobenzene (2TFMPDA), 1-(3,5-diaminophenyl)-2,2-bis(trifluoromethyl)- 3,3,4,4,5,5,5-heptafluoropentane, 3,5-diaminotoluenetrifluoride (3,5-DABTF), 3,5-diamino-5-(pentafluoroethyl)benzene, 3,5-diamino-5-(heptafluoropropyl)benzene, 2,2'-dimethylbenzidine (DMBZ), 2,2',6,6'-tetramethylbenzidine (TMBZ), 3,6-diamino-9,9-bis(trifluoromethyl)benzene (6FCDAM), 3,6-diamino-9-trifluoromethyl-9-phenyl (3FCDAM), 3,6-diamino-9,9-diphenyl The compounds represented, etc.

The molar ratio of diamine to dianhydride is generally 1:1. To achieve the desired terminal structure, one of the diamines may be used in excess. Specifically, using an excess of diamine facilitates the formation of amino groups at the ends (both ends) of the polyimide (A2). On the other hand, using an excess of dianhydride facilitates the formation of anhydride groups at the ends (both ends) of the polyimide (A2). As described above, in this embodiment, the polyimide (A2) preferably has anhydride groups at its ends. Therefore, in this embodiment, it is preferred to use an excess of dianhydride during the synthesis of the polyimide (A2).

Alternatively, the terminal amino groups and/or anhydride groups of the polyimide obtained by polycondensation can be reacted with a certain reagent to impart desired functional groups to the polyimide terminals.

The molecular weight of the polyimide (A2), as measured by a polystyrene-equivalent weight average molecular weight obtained by gel permeation chromatography, is preferably 5,000 to 150,000, more preferably 7,000 to 100,000, and even more preferably 10,000 to 50,000. A weight average molecular weight of 5,000 or greater is preferred due to good mechanical properties, while a weight average molecular weight of 150,000 or less is preferred due to good dispersibility in the developer and good relief pattern resolution. Tetrahydrofuran and N-methyl-2-pyrrolidone are recommended as developing solvents for gel permeation chromatography. The molecular weight is determined from a calibration curve created using standard monodisperse polystyrene. We recommend using the organic solvent standard sample STANDARD SM-105 manufactured by Showa Denko Co., Ltd. as the standard monodisperse polystyrene.

(B) Flavonoids

The flavonoids (B) used in this embodiment are not limited as long as they are compounds represented by the following formula (1) or (1-2).

[Chemistry 26]

(In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group.)

By making the flavonoid (B) the above-mentioned formula (1) or formula (1-2), excellent copper adhesion and copper porosity suppression effects, as well as storage stability, can be achieved. Although not bound by theory, it is believed that by having a hydroxyl group in the different aromatic groups in the structure, hydrogen bonds can be formed with both the copper layer and the resin layer, thereby improving copper adhesion. In addition, it is believed that by having multiple aromatic hydroxyl groups, oxidation reactions at the copper interface are strongly suppressed, thereby suppressing copper porosity. Regarding storage stability, it is believed that the reason is that the presence of aromatic hydroxyl groups in the structure captures free radicals that are unintentionally generated in the system, preventing the viscosity increase or gelation associated with polymer crosslinking.

From the perspective of copper adhesion, the flavonoid (B) is preferably a compound represented by the following general formula (2-2):

(where _n2 is 0 or 1, and _R1 is an aromatic group having at least one hydroxyl group and may further have other substituents)

More preferably, it is a compound represented by the following general formula (3-2).

(In the formula, _R1 is an aromatic group having at least one hydroxyl group and may further have other substituents)

It is believed that by having multiple hydroxyl groups on the same aromatic ring of flavonoid (B), the interaction with the copper layer or resin layer is enhanced, and the copper bonding becomes better.

From the perspective of copper adhesion, the flavonoid (B) is preferably a compound represented by the following general formula (2).

(Where _n1 is an integer between 1 and 3, _n2 is 0 or 1, and _n3 is an integer between 1 and 2)

It is believed that by ensuring that the flavonoid (B) does not have any groups other than hydroxyl groups in addition to the flavonoid skeleton, it will not sterically hinder the interaction with the copper layer, thus improving the copper bonding.

Furthermore, from the perspective of copper adhesion and copper porosity suppression, the flavonoid (B) is preferably a compound represented by the following general formula (3).

(Where _n4 is 2 or 3, _n5 is 1 or 2)

From the perspective of storage stability, the flavonoid (B) is preferably a compound represented by the following general formula (4).

(where n ₄ is 2 or 3)

It is speculated that by including a large number of aromatic hydroxyl groups in the flavonoid (B) molecule, the hydrogen bonds with the copper layer or resin layer become stronger. Furthermore, it is believed that the oxidation inhibition effect is enhanced, further suppressing copper porosity and similarly improving the stability preservation effect.

Examples of flavonoids (B) include, but are not limited to, isorhamnetin, ginsengone, apigenin, quercetin, quercetin, flavonoids, flavonol, daidzein, isorhamnetin, flavonol, genistein, morin, apigenin, flavonoids, naringenin, hesperetin, dihydroquercetin, and (+)-dihydroquercetin. Among these, quercetin, quercetin, flavonoids, flavonoids, and morin are preferred.

Furthermore, when these compounds are added to the resin composition, they may be in the form of hydrates.

The amount of flavonoid (B) added per 100 parts by mass of resin (A) is preferably 3 parts by mass or more and 20 parts by mass or less, and more preferably 10 parts by mass or more and 20 parts by mass or less. From the perspective of copper porosity suppression, the amount is preferably 3 parts by mass or more, and from the perspective of copper adhesion, it is preferably 20 parts by mass or less. An amount less than 3 parts by mass will not sufficiently suppress copper porosity, while an amount exceeding 20 parts by mass will reduce copper adhesion. While the reason for this reduced copper adhesion is not certain, it is believed that excessive amounts of flavonoid (B) may create a weak layer between the copper layer and the resin layer.

(C) Photopolymerization initiator

The (C) photopolymerization initiator used in this embodiment is described below. As the photopolymerization initiator, a photo-free radical polymerization initiator is preferred, and preferably exemplified are: benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl ketone, dibenzyl ketone, benzophenone derivatives such as fluorenone, acetophenone derivatives such as 2,2'-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexylphenyl ketone, 9-oxysulfuron, , 2-methyl-9-oxosulfur , 2-isopropyl-9-oxosulfur , diethyl-9-oxosulfur 9-oxosulfur derivatives, benzoyl, benzoyl dimethyl ketal, benzoyl-β-methoxyethyl acetal and other benzoyl derivatives, benzoin, benzoin methyl ether and other benzoin derivatives, 1-phenyl-1,2-butanedione-2-(o-methoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2-(o-methoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2 Examples of photopolymerization initiators include, but are not limited to, oximes such as 1,3-diphenylpropane-2-(o-ethoxycarbonyl)oxime, 1-phenyl-3-ethoxypropane-2-(o-benzoyl)oxime, N-arylglycine such as N-phenylglycine, peroxides such as benzoyl perchloride, aromatic biimidazoles, titanium cyclopentadiene, and photoacid generators such as α-(n-octanesulfonyloxyimino)-4-methoxyphenylacetonitrile. Among the above-mentioned photopolymerization initiators, oximes are particularly preferred in terms of photosensitivity.

The amount of the photopolymerization initiator (C) to be added is preferably 0.1 to 20 parts by mass per 100 parts by mass of the resin (A), more preferably 1 to 8 parts by mass, and even more preferably 1 to 5 parts by mass. From the perspective of photosensitivity or patterning properties, the amount is preferably 0.1 parts by mass or greater, and from the perspective of the physical properties of the photosensitive resin layer after curing of the negative photosensitive resin composition, it is preferably 20 parts by mass or less.

(D)Solvent

The solvent (D) used in this embodiment will be described. Examples of the solvent include amides, sulfoxides, ureas, ketones, esters, lactones, ethers, alkyl halides, alkyls, and alcohols. Examples of the solvent include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, tetramethylurea, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, ethyl lactate, methyl lactate, butyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, benzyl alcohol, phenylene glycol, tetrahydrofurfuryl alcohol, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, The preferred resins include 1,2-dichloromethane, 1,4-dichlorobutane, chlorobenzene, o-dichlorobenzene, anisole, hexane, heptane, benzene, toluene, xylene, and mesitylene. Among these, preferred resins are N-methyl-2-pyrrolidone, dimethyl sulfoxide, tetramethylurea, butyl acetate, ethyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, diethylene glycol dimethyl ether, benzyl alcohol, phenylene glycol, 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide, and tetrahydrofurfuryl alcohol from the perspectives of resin solubility, resin composition stability, and substrate adhesion.

Among such solvents, those that completely dissolve the polyimide precursor or polyimide are particularly preferred. Examples include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, tetramethylurea, γ-butyrolactone, 3-methoxy-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide. From the perspective of achieving in-plane uniformity when coating the photosensitive resin composition on a substrate, γ-butyrolactone and 3-methoxy-N,N-dimethylpropionamide are particularly preferred.

The solvent may be a single species or a mixture of two or more. From the perspective of appropriately adjusting the stability of the resin composition, two or more species are preferred. When two or more solvents are used, from the perspective of in-plane uniformity, it is preferred that at least 50% by weight of the solvent be either γ-butyrolactone or 3-methoxy-N,N-dimethylpropionamide, with γ-butyrolactone being particularly preferred.

In the photosensitive resin composition of this embodiment, the amount of solvent used is preferably 100-1000 parts by mass, more preferably 120-700 parts by mass, and even more preferably 125-500 parts by mass, relative to 100 parts by mass of resin (A).

The negative photosensitive resin composition of this embodiment may further contain components other than the aforementioned components (A) to (D). Components other than components (A) to (D) are not limited and include, for example, heterocyclic compounds, free radical polymerizable compounds, thermal alkali generators, hindered phenol compounds, organic titanium compounds, bonding agents, sensitizers, and polymerization inhibitors.

The negative photosensitive resin composition of this embodiment may also contain a heterocyclic compound. Examples of heterocyclic compounds include azole compounds and purine derivatives.

Examples of the azole compound include 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, 4-tert-butyl-5-phenyl-1H-triazole, 5-hydroxyphenyl-1H-triazole, phenyltriazole, p-ethoxyphenyltriazole, 5-phenyl-1-(2-dimethylaminoethyl)triazole, 5-benzyl-1H-triazole, hydroxyphenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-1H-triazole, and the like. ]-Benzotriazole, 2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-tert-butyl-5-methyl-2-hydroxyphenyl)-benzotriazole, 2-(3,5-di-tert-pentyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole, etc.

Among them, preferred examples include 5-amino-1H-tetrazole, tolyltriazole, 5-methyl-1H-benzotriazole, and 4-methyl-1H-benzotriazole.

Specific examples of purine derivatives include purine, adenine, guanine, hypoxanthine, xanthine, theobromine, caffeine, uric acid, isoguanine, 2,6-diaminopurine, 9-methyladenine, 2-hydroxyadenine, 2-methyladenine, 1-methyladenine, N-methyladenine, N,N-dimethyladenine, 2-fluoroadenine, 9-(2-hydroxyethyl)adenine, guanine oxime, N-(2-hydroxyethyl)adenine, 8-Aminoadenine, 6-amino-8-phenyl-9H-purine, 1-ethyladenine, 6-ethylaminopurine, 1-benzyladenine, N-methylguanine, 7-(2-hydroxyethyl)guanine, N-(3-chlorophenyl)guanine, N-(3-ethylphenyl)guanine, 2-azaadenine, 5-azaadenine, 8-azaadenine, 8-azaguanine, 8-azapurine, 8-azaxanthine, 8-azahypoxanthine, and their derivatives.

Furthermore, these heterocyclic compounds may be used alone or as a mixture of two or more.

When the photosensitive resin composition contains a heterocyclic compound, the amount blended is preferably 0.1 to 10 parts by mass per 100 parts by mass of the resin (A), and more preferably 0.5 to 5 parts by mass from the perspective of copper adhesion. When the amount of the (E) heterocyclic compound blended is 0.1 parts by mass or greater per 100 parts by mass of the resin (A), discoloration of copper is suppressed when the photosensitive resin composition of this embodiment is formed on copper. On the other hand, when the amount of the (E) heterocyclic compound blended is 10 parts by mass or less per 100 parts by mass of the resin (A), excellent copper adhesion is achieved.

Free radical polymerizable compounds

The negative photosensitive resin composition in this embodiment may also contain a free radical polymerizable compound to enhance the chemical resistance of the cured relief pattern. To achieve good chemical resistance, the free radical polymerizable compound is preferably present in an amount of 5 parts by mass or greater, more preferably 10 parts by mass or greater, even more preferably 30 parts by mass or greater, and even more preferably 40 parts by mass or greater, relative to 100 parts by mass of resin (A). From the perspective of patterning properties, the free radical polymerizable compound is preferably present in an amount of 150 parts by mass or less, more preferably 100 parts by mass or less, and even more preferably 80 parts by mass or less.

The radical polymerizable compound in this embodiment is not particularly limited as long as it is a compound that undergoes radical polymerization reaction with a photopolymerization initiator. Preferably, it is a (meth)acrylic acid compound, for example, represented by the following general formula (14):

{In formula (14), X ₁₁ is an organic group, L ₁₁ , L ₁₂ , and L ₁₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms. _{n 11} is an integer of 1 to 10}.

Examples of free radical polymerizable compounds include mono- or di-acrylates and methacrylates of ethylene glycol or polyethylene glycol such as diethylene glycol dimethacrylate and tetraethylene glycol dimethacrylate; mono- or di-acrylates and methacrylates of propylene glycol or polypropylene glycol; mono-, di- or tri-acrylates and methacrylates of glycerol; cyclohexane diacrylate and dimethacrylate; diacrylate and dimethacrylate of 1,4-butanediol; diacrylate and dimethacrylate of 1,6-hexanediol; diacrylate and dimethacrylate of neopentyl glycol; mono- or di-acrylate and methacrylate of bisphenol A; benzyltrimethacrylate; isoacrylate Ester and methacrylate Examples of the present invention include, but are not limited to, esters, acrylamide and its derivatives, methacrylamide and its derivatives, trihydroxymethylpropane triacrylate and methacrylate, glycerol di- or triacrylate and methacrylate, pentaerythritol di-, tri-, or tetraacrylate and methacrylate, and ethylene oxide or propylene oxide adducts of these compounds. More specifically, the compounds represented by the following formulas are exemplified, but are not limited to:

[Chemistry 34-2]

In this specification, a radically polymerizable compound with one radically polymerizable group is referred to as monofunctional. A radically polymerizable compound with two or more radically polymerizable groups is referred to as x-functional, depending on the number x of radically polymerizable groups. Radically polymerizable compounds with two or more radicals are sometimes collectively referred to as polyfunctional. Radically polymerizable compounds may be monofunctional or difunctional or higher. From the perspective of chemical resistance, radically polymerizable compounds are preferably trifunctional or higher, more preferably tetrafunctional or higher, and even more preferably hexafunctional or higher. On the other hand, from the perspective of elongation at break, decafunctional or lower is preferred.

The molecular weight of the radically polymerizable compound is preferably 100 or greater, more preferably 200 or greater, and even more preferably 300 or greater. The upper limit is preferably 1000 or less, and even more preferably 800 or less. By setting the molecular weight within this range, chemical resistance and patterning properties are improved.

It is preferred that at least one of the radically polymerizable compounds used in this embodiment is a radically polymerizable compound having at least one of a hydroxyl group and a urea group.

As a radical polymerizable compound having a hydroxyl group in the molecule, the structure represented by the following general formula (15) can be cited:

{In formula (15), X ₁₁ is an organic group, L ₁₁ , L ₁₂ , and L ₁₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms. _{n 11} is an integer of 1 to 10, and n ₁₂ is an integer of 1 to 10}.

From the viewpoint of free radical reactivity, it is preferred that in the above formula (15), L ₁₁ is a hydrogen atom or a methyl group, and L ₁₂ and L ₁₃ are hydrogen atoms. More specifically, the compounds represented by the following formulas can be exemplified, but are not limited to the following: [Chemical 36]

Chemical resistance is particularly improved by having hydroxyl groups in the molecular structure. The number of hydroxyl groups in the molecular structure is preferably one or more, more preferably two or more. The upper limit is preferably 10 or less, more preferably 6 or less, and even more preferably 3 or less. By setting the above range, chemical resistance and adhesion to the substrate are improved.

The radical polymerizable compound having a urea group in its molecule can be represented by the following general formula (16):

{In formula (16), X ₂₀ , X ₂₁ , X ₂₂ , and X ₂₃ are each independently a hydrogen atom, a monovalent organic group having a group represented by the following general formula (17), or a monovalent organic group having 1 to 20 carbon atoms which may contain a heteroatom; at least one of X ₂₀ , X ₂₁ , X ₂₂ , and X ₂₃ is a monovalent organic group having a group represented by the following general formula (17)}

{In formula (17), L ₁₁ , L ₁₂ , and L ₁₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms}.

From the viewpoint of radical reactivity, it is preferred that in the above formula (17), L ₁₁ is a hydrogen atom or a methyl group, and L ₁₂ and L ₁₃ are hydrogen atoms.

Examples of heteroatoms in this embodiment include oxygen atoms, nitrogen atoms, phosphorus atoms, and sulfur atoms.

In formula (16), when _X₂₀ , _X₁₁ , _X₂₂ , and _X₂₃ are monovalent organic groups having 1 to 20 carbon atoms that may contain a heteroatom, from the perspective of developing properties, they preferably contain an oxygen atom. The carbon number is not limited as long as it is 1 to 20. From the perspective of heat resistance, it is preferably 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. _X₂₀ , _X₁₁ , _X₂₂ , and _X₂₃ in formula (16) may be bonded to each other to form a cyclic structure. However, from the perspective of chemical resistance, it is preferred that they not have a cyclic structure. By bonding _X20 , _X21 , _X22 , and _X23 to form a cyclic structure, the urea group loses its bonding angle freedom, making it difficult to form a strong hydrogen bond. From the perspective of forming hydrogen bonds with other molecules, it is preferred that at least one of _X20 , _X21 , _X22 , and _X23 is a hydrogen atom. On the other hand, from the perspective of solubility, the number of hydrogen atoms in _X20 , _X21 , _X22 , and _X23 is preferably two or less. Specifically, the compound represented by the following formula can be exemplified: [Chemical 39]

In this embodiment, the radical polymerizable compound preferably has at least one hydroxyl group and at least one urea group in the molecule. The radical polymerizable compound having at least one hydroxyl group and at least one urea group in the molecule can be represented by the following general formula (18):

{In formula (18), X ₃₀ , X ₃₁ , X ₃₂ , and X ₃₃ are each independently a hydrogen atom, a monovalent organic group having a group represented by the following general formula (19), or a monovalent organic group having 1 to 20 carbon atoms which may contain a heteroatom; at least one of X ₃₀ , X ₃₁ , X ₃₂ , and X ₃₃ is a monovalent organic group having a group represented by the following general formula (19), and at least one is a hydroxyl group}

{In formula (19), L ₁₁ , L ₁₂ , and L ₁₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms}.

From the viewpoint of radical reactivity, it is preferred that in the above formula (19), L ₁₁ is a hydrogen atom or a methyl group, and L ₁₂ and L ₁₃ are hydrogen atoms.

In formula (18), when _X30 , _X31 , _X32 , and _X33 are monovalent organic groups having 1 to 20 carbon atoms that may contain a heteroatom, from the perspective of developing properties, they preferably contain an oxygen atom. The carbon number is not limited as long as it is 1 to 20. From the perspective of heat resistance, it is preferably 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. In formula (19), _X30 , _X31 , _X32 , and _X33 may be mutually bonded to form a cyclic structure. From the perspective of chemical resistance, they preferably do not have a cyclic structure. By mutually bonding _X30 , _X31 , _X32 , and _X33 to form a cyclic structure, the urea group loses its degree of freedom at the bonding angle, making it difficult to form a strong hydrogen bond. From the perspective of forming hydrogen bonds with other molecules, it is preferred that at least one of _X30 , _X31 , _X32 , and _X33 is a hydrogen atom. On the other hand, from the perspective of solubility, the number of hydrogen atoms in _X30 , _X31 , _X32 , and _X33 is preferably two or less. Specifically, compounds represented by the following formulas can be exemplified:

Among the free-radically polymerizable compounds in this embodiment, the method for producing the free-radically polymerizable compound having a urea group is not particularly limited. For example, it can be obtained by reacting an isocyanate compound having a free-radically polymerizable group with an amine-containing compound. When the amine-containing compound contains a functional group such as a hydroxyl group that is reactive with the isocyanate, a compound formed by reacting a portion of the isocyanate compound with a functional group such as a hydroxyl group may also be included.

In this embodiment, the radically polymerizable compound may be used singly, but is preferably used as a mixture of two or more. By using two or more, chemical resistance and in-plane uniformity are improved. While the reason for this improved in-plane uniformity is speculative, it is believed that when a large amount of a single radically polymerizable compound is added, microphase separation occurs with the resin component of the varnish. For this reason, when a radically polymerizable compound is used singly, the amount is preferably 60 parts by mass or less, and more preferably 40 parts by mass or less, per 100 parts by mass of the resin.

When two or more radical polymerizable compounds are mixed, the number is preferably six or less, and more preferably four or less, from the perspective of controlling the crosslinking density.

When using a mixture of multiple radically polymerizable compounds, it is preferred that at least one of the compounds have a different number of functional groups. When using three or more radically polymerizable compounds, it suffices that at least one of the compounds have a different number of functional groups, and it is preferred that all of the compounds have different numbers of functional groups. When using multiple radically polymerizable compounds, it is preferred that at least one of the compounds contain a monofunctional radically polymerizable compound from the perspective of elongation at break.

When two or more radically polymerizable compounds are mixed, it is preferred to include at least one each of a nitrogen-containing radically polymerizable compound and a nitrogen-free radically polymerizable compound. The nitrogen-containing radically polymerizable compound is preferably a urea-containing radically polymerizable compound. Nitrogen-containing radically polymerizable compounds form strong hydrogen bonds, resulting in excellent chemical resistance. However, the addition of multiple nitrogen-containing radically polymerizable compounds results in a complex hydrogen bond network, resulting in insufficient solubility.

Thermoalkali generators

The negative photosensitive resin composition of this embodiment may also contain a base generator. A base generator is a compound that generates a base upon heating. The inclusion of a thermal base generator can further promote the imidization of the photosensitive resin composition.

The type of the pyroalkali generator is not particularly limited, but examples thereof include amine compounds protected by a tert-butoxycarbonyl group and the pyroalkali generator disclosed in International Publication No. 2017/038598. However, the invention is not limited to these, and other known pyroalkali generators may also be used.

Examples of the amine compound protected by the tert-butoxycarbonyl group include, but are not limited to, ethanolamine, 3-amino-1-propanol, 1-amino-2-propanol, 2-amino-1-propanol, 4-amino-1-butanol, 2-amino-1-butanol, 1-amino-2-butanol, 3-amino-2,2-dimethyl-1- Propanol, 4-amino-2-methyl-1-butanol, hydroxypropylaminoethanol, 3-amino-1,2-propanediol, 2-amino-1,3-propanediol, tyramine, norephedrine, 2-amino-1-phenyl-1,3-propanediol, 2-aminocyclohexanol, 4-aminocyclohexanol, 4-aminocyclohexaneethanol, 4-(2-aminoethyl)cyclohexanol, N-methylethanolamine, 3-(methylamino)-1-propanol, 3-(iso propylamino)propanol, N-cyclohexylethanolamine, α-[2-(methylamino)ethyl]benzyl alcohol, diethanolamine, diisopropanolamine, 3-pyrrolidinol, 2-pyrrolidinolmethanol, 4-hydroxypiperidine, 3-hydroxypiperidine, 4-hydroxy-4-phenylpiperidine, 4-(3-hydroxyphenyl)piperidine, 4-piperidinemethanol, 3-piperidinemethanol, 2-piperidinemethanol, 4-piperidineethanol, 2-piperidineethanol, 2-(4-piperidine) 1,4-Butanol bis(3-aminopropyl) ether, 1,2-bis(2-aminoethoxy)ethane, 2,2'-oxybis(ethylamine), 1,14-diamino-3,6,9,12-tetraoxotetradecane, 1-aza-15-crown-5, diethylene glycol bis(3-aminopropyl) ether, 1,11-diamino-3,6,9-trioxaundecane, or amino acids and their derivatives.

The amount of the alkali generator added per 100 parts by mass of the resin (A) is preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 parts by mass. The above amount is preferably 0.1 parts by mass or more to enhance the effect of accelerating imidization, and is preferably 20 parts by mass or less to enhance the physical properties of the cured photosensitive resin layer of the negative photosensitive resin composition.

Hindered phenol compounds

In order to suppress discoloration on the copper surface, the negative photosensitive resin composition may also optionally contain a hindered phenol compound. The hindered phenol compound is not limited, and examples thereof include: 2,6-di-tert-butyl-4-methylphenol, 2,5-di-tert-butyl-hydroquinone, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, isooctyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 4,4'-methylenebis(2,6-di-tert-butylphenol), 4,4'-thiobis(3-methyl-6-tert-butylphenol), 4,4'-butylenebis(3-methyl-6-tert-butylphenol), triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], Tributyl-4-hydroxyphenyl) propionate], 2,2-thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide), 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], tris-(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, etc.

Examples of hindered phenol compounds include 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-isopropylbenzyl)- ... -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-sec-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-tris(4-sec-butyl-3-hydroxy-2,6-dimethylbenzyl) -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-(1-ethylpropyl)-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-tris -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-triethylmethyl-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-phenylbenzyl)-1,3,5-tris(1H,3H,5H)-trione -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,5,6-trimethylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-5-ethyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-6-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-6-ethyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-5,6-diethyl-3-hydroxy-2-methylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-3-hydroxy-2-methylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-tris(4-tert-butyl-3-hydroxy-2,5-dimethylbenzyl) -2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-tert-butyl-5-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-tri -2,4,6-(1H,3H,5H)-trione, etc., but not limited thereto.

Among them, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)- -2,4,6-(1H,3H,5H)-trione, etc.

The amount of the hindered phenol compound blended per 100 parts by mass of the resin (A) is preferably 0.1 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass from the perspective of photosensitivity. When the hindered phenol compound blended in an amount of 0.1 parts by mass or greater per 100 parts by mass of the resin (A) prevents discoloration and corrosion of copper or a copper alloy when the photosensitive resin composition of this embodiment is formed on it. On the other hand, when the hindered phenol compound blended in an amount of 20 parts by mass or less per 100 parts by mass of the resin (A) exhibits excellent photosensitivity.

Organic titanium compounds

The negative photosensitive resin composition of this embodiment may also contain an organic titanium compound. By including an organic titanium compound, a photosensitive resin layer with excellent chemical resistance can be formed even when curing at low temperatures.

Examples of usable organic titanium compounds include organic chemical substances bonded to titanium atoms via covalent bonds or ionic bonds.

Specific examples of organic titanium compounds are shown in I) to VII) below:

I) Titanium Chelate Compounds: Titanium chelates with two or more alkoxy groups are particularly preferred for enhancing the storage stability of negative photosensitive resin compositions and achieving good patterns. Specific examples include titanium bis(triethanolamine)diisopropylate, titanium bis(2,4-pentanedioate)di-n-butanol, titanium bis(2,4-pentanedioate)diisopropylate, titanium bis(tetramethylpimelate)diisopropylate, and titanium bis(ethyl acetylacetate)diisopropylate.

II) Tetraalkoxy titanium compounds: Examples include titanium tetra-n-butoxide, titanium tetraethanol, titanium tetra(2-ethylhexanol), titanium tetraisobutoxide, titanium tetraisopropoxide, titanium tetramethanol, titanium tetramethoxypropoxide, titanium tetramethylphenol, titanium tetra-n-nonoxide, titanium tetra-n-propoxide, titanium tetrastearyl alcohol, and titanium tetra[bis{2,2-(allyloxymethyl)butanol}].

III) Titanium cyclopentadienyl compounds: Examples include (pentamethylcyclopentadienyl)trimethoxide, bis(η5-2,4-cyclopentadien-1-yl)bis(2,6-difluorophenyl)titanium, and bis(η5-2,4-cyclopentadien-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium.

IV) Monoalkoxy titanium compounds: for example, titanium tris(dioctyl phosphate) isopropylate, titanium tris(dodecylbenzenesulfonic acid) isopropylate, etc.

V) Titanium oxide compounds: for example, bis(glutaric acid)titanium oxide, bis(tetramethylpimelate)titanium oxide, phthalocyanine titanium oxide, etc.

VI) Titanium tetraacetylacetonate compounds: for example, titanium tetraacetylacetonate.

VII) Titanium ester coupling agent: for example, tri(dodecylbenzenesulfonyl)titanium isopropyl ester, etc.

Among these, from the perspective of exhibiting better chemical resistance, the preferred organic titanium compound is at least one compound selected from the group consisting of I) titanium chelate compounds, II) tetraalkoxytitanium compounds, and III) titaniumocene compounds. Particularly preferred are titanium bis(ethyl acetylacetate)diisopropoxide, titanium tetra-n-butoxide, and bis(η5-2,4-cyclopentadien-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium.

When an organic titanium compound is added, the amount is preferably 0.05-10 parts by mass, more preferably 0.1-2 parts by mass, per 100 parts by mass of resin (A). Amounts of 0.05 parts by mass or greater exhibit excellent heat resistance and chemical resistance. On the other hand, amounts of 10 parts by mass or less exhibit excellent storage stability.

Then the additives

In order to improve the adhesion between the film formed using the negative photosensitive resin composition of this embodiment and the substrate, the negative photosensitive resin composition may also optionally contain an adhesion aid. Examples of the bonding aid include γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-butylpropylmethyldimethoxysilane, 3-methacryloyloxypropyldimethoxymethylsilane, 3-methacryloyloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinylpropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N-(3-diethoxymethylsilylpropyl)succinimide, N-[3-(triethoxysilyl)propyl]phthalimide, and the like. Silane coupling agents such as formamide, benzophenone-3,3'-bis(N-[3-triethoxysilyl]propylamide)-4,4'-dicarboxylic acid, benzene-1,4-bis(N-[3-triethoxysilyl]propylamide)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propylsuccinic anhydride, N-phenylaminopropyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, and 3-(trialkoxysilyl)propylsuccinic anhydride; and aluminum-based bonding agents such as tris(ethyl acetylacetate)aluminum, tris(acetylacetone)aluminum, and aluminum diisopropyl acetylacetate.

Among these bonding agents, silane coupling agents are more preferred in terms of adhesion. When the photosensitive resin composition contains a bonding agent, the amount of the bonding agent is preferably in the range of 0.5-25 parts by mass per 100 parts by mass of the resin (A).

The silane coupling agent is not limited, and examples thereof include: 3-butylpropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: trade name KBM803, manufactured by Chisso Co., Ltd.: trade name Sila-Ace S810), 3-Benzylpropyltriethoxysilane (manufactured by Azmax Co., Ltd.: trade name SIM6475.0), 3-Benzylpropylmethyldimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: trade name LS1375, manufactured by Azmax Co., Ltd.: trade name SIM6474.0), Benzylmethyltrimethoxysilane (manufactured by Azmax Co., Ltd.: trade name SIM6473.5C), Benzylmethylmethyldimethoxysilane (manufactured by Azmax Co., Ltd.: trade name SIM6473.0), 3-Benzylpropyldiethoxymethoxysilane, 3-Benzylpropylethoxydimethoxysilane, 3-Benzyl Propyltripropoxysilane, 3-Alkylpropyldiethoxypropoxysilane, 3-Alkylpropylethoxydipropoxysilane, 3-Alkylpropyldimethoxypropoxysilane, 3-Alkylpropylmethoxydipropoxysilane, 2-Alkylethyltrimethoxysilane, 2-Alkylethyldiethoxymethoxysilane, 2-Alkylethylethoxydimethoxysilane Silane, 2-benzylethyltripropoxysilane, 2-benzylethyltripropoxysilane, 2-benzylethylethoxydipropoxysilane, 2-benzylethyldimethoxypropoxysilane, 2-benzylethylmethoxydipropoxysilane, 4-benzylbutyltrimethoxysilane, 4-benzylbutyltriethoxysilane, 4-benzylbutyl tripropoxysilane, etc.

The silane coupling agent is not limited, and examples thereof include N-(3-triethoxysilylpropyl)urea (manufactured by Shin-Etsu Chemical Co., Ltd.: trade name LS3610, manufactured by Azmax Co., Ltd.: trade name SIU9055.0), N-(3-trimethoxysilylpropyl)urea (manufactured by Azmax Co., Ltd.: trade name SIU9058.0), N-(3-diethoxymethoxysilylpropyl)urea, , N-(3-ethoxydimethoxysilylpropyl)urea, N-(3-tripropoxysilylpropyl)urea, N-(3-diethoxypropoxysilylpropyl)urea, N-(3-ethoxydipropoxysilylpropyl)urea, N-(3-dimethoxypropoxysilylpropyl)urea, N-(3-methoxydipropoxysilylpropyl)urea, N-(3-trimethoxysilylethyl)urea, N-(3-ethoxydimethoxysilylethyl)urea, N-(3-Tripropoxysilylethyl)urea, N-(3-tripropoxysilylethyl)urea, N-(3-ethoxydipropoxysilylethyl)urea, N-(3-dimethoxypropoxysilylethyl)urea, N-(3-methoxydipropoxysilylethyl)urea, N-(3-trimethoxysilylbutyl)urea, N-(3-triethoxysilylbutyl)urea, N-(3-tripropoxysilylbutyl)urea, 3-(m-aminophenoxy) Propyltrimethoxysilane (Azmax Co., Ltd.: Trade name SLA0598.0), m-aminophenyltrimethoxysilane (Azmax Co., Ltd.: Trade name SLA0599.0), p-aminophenyltrimethoxysilane (Azmax Co., Ltd.: Trade name SLA0599.1), aminophenyltrimethoxysilane (Azmax Co., Ltd.: Trade name SLA0599.2), etc.

Examples of silane coupling agents include 2-(trimethoxysilylethyl)pyridine (manufactured by Azmax Co., Ltd.: trade name SIT8396.0), 2-(triethoxysilylethyl)pyridine, 2-(dimethoxysilylmethylethyl)pyridine, 2-(diethoxysilylmethylethyl)pyridine, (3-triethoxysilylpropyl)-tert-butylcarbamate, (3-glycidyloxypropyl)triethoxysilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-isopropoxysilane, tetra- -n-Butoxysilane, Tetra-isobutoxysilane, Tetra-tert-butoxysilane, Tetra-methoxyethoxysilane, Tetra-methoxy-n-propoxysilane, Tetra-ethoxyethoxysilane, Tetra-methoxyethoxyethoxysilane, Bis(trimethoxysilyl)ethane, Bis(trimethoxysilyl)hexane, Bis(triethoxysilyl)methane, Bis(triethoxysilyl)ethane, Bis(triethoxysilyl)ethylene, Bis(triethoxysilyl)octane, Bis(triethoxysilyl)octadiene, Bis[3-(triethoxysilyl)propyl]dione Sulfide, Bis[3-(triethoxysilyl)propyl]tetrasulfide, Di-tert-butoxydiethoxysilane, Di-isobutoxyaluminoxytriethoxysilane, Phenylsilanetriol, Methylphenylsilanediol, Ethylphenylsilanediol, n-Propylphenylsilanediol, Isopropylphenylsilanediol, n-Butylphenylsilanediol, Isobutylphenylsilanediol, tert-Butylphenylsilanediol, Diphenylsilanediol, Dimethoxydiphenylsilane, Diethoxydiphenylsilane, Dimethoxydi-p-tolylsilane, Ethylmethylphenylsilanol, n-Propylmethylphenylsilane Alcohol, isopropyl methylphenylsilanol, n-butyl methylphenylsilanol, isobutyl methylphenylsilanol, tert-butyl methylphenylsilanol, ethyl n-propyl phenylsilanol, ethyl isopropyl phenylsilanol, n-butyl ethylphenylsilanol, isobutyl ethylphenylsilanol, tert-butyl ethylphenylsilanol, methyl diphenylsilanol, ethyl diphenylsilanol, n-propyl diphenylsilanol, isopropyl diphenylsilanol, n-butyl diphenylsilanol, isobutyl diphenylsilanol, tert-butyl diphenylsilanol, triphenylsilanol, etc., but not limited to them.

The silane coupling agents listed above may be used alone or in combination. Among the silane coupling agents listed above, preferred from the viewpoint of storage stability are phenylsilanetriol, trimethoxyphenylsilane, trimethoxy(p-tolyl)silane, diphenylsilanediol, dimethoxydiphenylsilane, diethoxydiphenylsilane, dimethoxydi-p-tolylsilane, triphenylsilanol, and silane coupling agents having a structure represented by the following formula:

When using a silane coupling agent, the preferred amount is 0.01-20 parts by mass per 100 parts by mass of resin (A).

Sensitizer

The negative photosensitive resin composition of this embodiment may also optionally contain a sensitizer to increase photosensitivity. Examples of the sensitizer include Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzylidene)cyclopentane, 2,6-bis(4'-diethylaminobenzylidene)cyclohexanone, 2,6-bis(4'-diethylaminobenzylidene)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, p-dimethylaminocinnamylene dihydroindanone, p-dimethylaminobenzylidene dihydroindanone, 2-(p-dimethylaminophenyl biphenylene)-benzothiazole, 2-(p-dimethylaminophenyl)-benzothiazole, 1,3-Bis(4'-dimethylaminobenzylidene)acetone, 1,3-Bis(4'-diethylaminobenzylidene)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3-acetyl-7-dimethylaminocoumarin, 3-ethoxycarbonyl-7-dimethylaminocoumarin, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin, N-phenyl-N'-ethylethanolamine, N-phenyldiethanolamine, N-p-tolyldiethanolamine, N-phenylethanolamine, 4- Benzophenone, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 2-benzimidazole, 1-phenyl-5-benzyltetrazol, 2-benzylbenzimidazole, 2-(p-dimethylaminostyryl)benzothiazole, azole, 2-(p-dimethylaminophenylvinyl)benzothiazole, 2-(p-dimethylaminophenylvinyl)naphtho(1,2-d)thiazole, 2-(p-dimethylaminophenylvinyl)styrene, etc. These can be used alone or in combination of 2 to 5 types.

When the photosensitive resin composition contains a sensitizer to enhance photosensitivity, the amount of the sensitizer added is preferably 0.1-25 parts by weight relative to 100 parts by weight of resin (A).

Polymerization inhibitors

Furthermore, the negative photosensitive resin composition of this embodiment may optionally contain a polymerization inhibitor to improve the viscosity and photosensitivity stability of the negative photosensitive resin composition, especially when stored in a solution containing a solvent. As polymerization inhibitors, hydroquinone, N-nitrosodiphenylamine, p-tert-butyl o-cyclopentylphenol, phenanthridine, , N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 2,6-di-tert-butyl-p-methylphenol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamine ammonium salt, N-nitroso-N-(1-naphthyl)hydroxylamine ammonium salt, etc.

<Method for manufacturing hardened relief pattern and semiconductor device>

The method for producing a hardened relief pattern of this embodiment comprises the following steps: (1) applying the negative photosensitive resin composition of this embodiment to a substrate to form a photosensitive resin layer on the substrate; (2) exposing the resin layer; (3) developing the exposed resin layer to form a relief pattern; and (4) heating the relief pattern to form a hardened relief pattern.

(1) Resin layer formation step

In this step, the negative photosensitive resin composition of this embodiment is applied to a substrate and then dried, if necessary, to form a photosensitive resin layer. Conventional methods for applying photosensitive resin compositions can be used, such as those using a rotary coater, bar coater, doctor blade coater, curtain coater, screen printer, or spray coating using a spray coater.

(2) Exposure step

In this step, an exposure device such as a contact aligner, mirror projection, or stepper is used to expose the resin layer formed above via a patterned mask or reticle, or directly using a UV light source.

(3) Embossed pattern formation step

In this step, the unexposed areas of the exposed photosensitive resin layer are removed by development. The development method for developing the exposed (irradiated) photosensitive resin layer can be any method selected from among conventional photoresist development methods, such as the spin spray method, the coating method, and the immersion method accompanied by ultrasonic treatment. Furthermore, a post-development bake at any combination of temperature and time may be performed after development, as needed, for purposes such as adjusting the shape of the relief pattern.

The developer used for development is preferably a good solvent for the negative photosensitive resin composition, or a combination of such a good solvent and a poor solvent. Examples of good solvents include N-methyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, and α-acetyl-γ-butyrolactone. Examples of poor solvents include toluene, xylene, methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, and water. When using a mixture of a good solvent and a poor solvent, it is preferable to adjust the ratio of the poor solvent to the good solvent based on the solubility of the polymer in the negative photosensitive resin composition. Alternatively, a combination of two or more solvents, such as a combination of several, may be used.

(4) Hardening relief pattern forming step

In this step, the relief pattern obtained by the development is heat-treated to evaporate the photosensitive component and imidize the polyimide precursor (A1), thereby converting it into a hardened relief pattern comprising polyimide. Various heat treatment methods can be used, such as using a hot plate, an oven, or a programmable temperature-controlled rising oven. Heat treatment can be performed, for example, at 160°C to 350°C for 30 minutes to 5 hours. The heat treatment temperature is preferably below 230°C, more preferably below 200°C, and even more preferably below 180°C. The atmosphere during heat curing can be air or an inert gas such as nitrogen or argon.

<Polyimide>

The polyimide of this embodiment can be produced by curing a negative photosensitive resin composition. Another aspect of the present invention provides a method for producing a cured polyimide film, comprising the steps of imidizing the negative photosensitive resin composition described above to form a cured polyimide having an imidization rate of 80-100%. The structure of the polyimide contained in the cured relief pattern formed from the polyimide precursor composition is represented by the following general formula.

{In the above general formula, X ₁ and Y ₁ are the same as X ₁ and Y ₁ in general formula (5), and m is a positive integer}

For the same reason, the preferred X ₁ and Y ₁ in formula (5) are also preferred in the polyimide having the structure represented by the above formula. In the above formula, the number of repeating units m is not particularly limited and can be an integer between 2 and 150.

<Semiconductor Devices>

This embodiment also provides a semiconductor device having a hardened relief pattern obtained by the above-described method for producing a hardened relief pattern. Thus, a semiconductor device can be provided having a substrate serving as a semiconductor element and a hardened relief pattern of polyimide formed on the substrate by the above-described method for producing a hardened relief pattern. Furthermore, this method can be applied to a method for producing a semiconductor device using a semiconductor element as a substrate and including the above-described method for producing a hardened relief pattern of this embodiment as a step. Semiconductor devices can be manufactured by forming a hardened relief pattern using the hardened relief pattern manufacturing method of this embodiment as a surface protective film, an interlayer insulating film, a redistribution insulating film, a flip-chip device protective film, or a protective film for semiconductor devices having a bump structure, and can be combined with conventional semiconductor device manufacturing methods.

<Display device>

In this embodiment, a display device is provided, comprising a display element and a cured film disposed on top of the display element, wherein the cured film comprises the aforementioned cured relief pattern. The cured relief pattern may be directly laminated on the display element, or laminated onto the display element with another layer interposed therebetween. Examples of the cured film include surface protective films, insulating films, and planarizing films for TFT (thin-film transistor) liquid crystal display elements and color filter elements, protrusions for MVA (Multi-Domain Vertical Alignment) liquid crystal display devices, and spacers for cathodes in organic EL (electroluminescence) elements.

The negative photosensitive resin composition of this embodiment is preferably used to form insulating members or interlayer insulating films. In addition to its application in semiconductor devices as described above, the negative photosensitive resin composition of this embodiment can also be used for interlayer insulating films in multilayer circuits, cover coatings for flexible copper foils, solder resists, and liquid crystal alignment films.

[Example]

The present embodiment is described in detail below using examples, but the present embodiment is not limited thereto. In the examples, comparative examples, and preparation examples, the physical properties of the resin or negative photosensitive resin composition were measured and evaluated according to the following methods.

(1) Weight average molecular weight

The weight average molecular weight (Mw) of each resin was measured using gel permeation chromatography (standard polystyrene conversion) under the following conditions.

Pump: JASCO PU-980

Detector: JASCO RI-930

Column oven: JASCO CO-965 40°C

Tube: Two Shodex KD-806M tubes manufactured by Showa Denko Co., Ltd. connected in series, or two Shodex 805M/806M tubes manufactured by Showa Denko Co., Ltd. connected in series.

Standard monodisperse polystyrene: Shodex STANDARD SM-105 manufactured by Showa Denko Co., Ltd.

Mobile phase: 0.1 mol/L LiBr/N-methyl-2-pyrrolidone (NMP)

Flow rate: 1 mL/min.

(2) Fabrication of hardened relief patterns on Cu

A 6-inch silicon wafer (Fujimi Electronics Industry Co., Ltd., thickness 625±25μm) was sputter-coated sequentially with 200nm thick titanium (Ti) and 400nm thick copper (Cu) using a sputtering apparatus (L-440S-FHL, manufactured by CANON ANELVA). Subsequently, a photosensitive resin composition prepared by the following method was spin-coated on the wafer using a coater developer (D-Spin60A, manufactured by SOKUDO Corporation). The film was pre-baked at 110°C for 180 seconds using a hot plate to form a coating film approximately 10μm thick. Using a photomask with a test pattern, the coating was irradiated with i-rays at an energy of 50-650 mJ/ ^cm² using a Prisma GHI (Ultratech). Subsequently, the coating was spray-developed using cyclopentanone as a developer for 1.4 times the time required for complete dissolution of the unexposed areas using a coating developer (D-Spin 60A, SOKUDO). The coating was then rinsed with propylene glycol methyl ether acetate for 10 seconds to obtain a relief pattern on the Cu substrate.

The wafer with the relief pattern formed on the Cu was heated at 230°C for 2 hours in a nitrogen atmosphere using a programmed temperature curing furnace (VF-2000, manufactured by Koyo Lindberg). This resulted in a hardened relief pattern consisting of a resin approximately 6-9 μm thick on the Cu.

(3) High temperature storage test of hardened relief pattern on Cu and subsequent porosity area evaluation

The wafer with the hardened relief pattern formed on the Cu was heated in air at 150°C for 168 hours using a programmed temperature curing furnace (VF-2000, manufactured by Koyo Lindberg). The resin layer on the Cu was then completely removed by plasma etching using a plasma surface treatment system (EXAM, manufactured by Shinko Seiki Co., Ltd.). The plasma etching conditions are as follows.

Output: 133W

Gas type and flow rate: O ₂ : 40mL/min + CF ₄ : 1mL/min

Gas pressure: 50Pa

Mode: Hard Mode

Etching time: 1800 seconds

After the resin layer was completely removed, the Cu surface was observed using an FE-SEM (S-4800, manufactured by Hitachi High-Technologies). Image analysis software (A image kun, manufactured by Asahi Kasei Corporation) was used to calculate the area of pores on the Cu surface. Taking the total area of pores in the evaluation of the photosensitive resin composition described in Comparative Example 1 as 100%, samples with a total area of pores less than 50% were rated "A," those with a total area of pores between 50% and 100% were rated "B," and those with a total area of pores greater than 100% were rated "C."

(3) Evaluation of copper adhesion

A 6-inch silicon wafer (Fujimi Electronics Industry Co., Ltd., thickness 625±25μm) was sputter-coated sequentially with 200nm thick titanium (Ti) and 400nm thick copper (Cu) using a sputtering apparatus (L-440S-FHL, manufactured by CANON ANELVA). A photosensitive resin composition was then spin-coated onto the wafer to a cured film thickness of approximately 9μm. After drying, the wafer was fully exposed and heated at 230°C for 2 hours in a programmed temperature curing furnace (VF-2000, manufactured by Koyo Lindberg) under a nitrogen atmosphere to obtain a hardened relief pattern (a thermally cured polyimide coating). For the heat-treated films, the adhesion properties between the copper substrate and the hardened resin coating were evaluated using the cross-cut method according to JIS K 5600-5-6 based on the following criteria.

A: The number of grids in the hardened resin coating on the substrate should be between 80 and 100.

B: The number of grids in the cured resin coating on the substrate is greater than 40 but less than 80.

C: The number of grids in the hardened resin coating on the substrate is less than 40.

(4) Preservation stability evaluation

The photosensitive resin composition prepared by the following method was placed in a sealed container and placed in an insulated container at 40°C for 4 days. The smaller the viscosity change of the composition, the better the storage stability. Storage stability was evaluated based on the following criteria.

A: The viscosity of the photosensitive resin composition is above 35 poise and below 45 poise.

B: The viscosity of the photosensitive resin composition is above 45 poise or below 35 poise.

C: Gelation of photosensitive resin composition

Preparation Example 1: (A) Synthesis of Polyimide Precursor A1

124.0 g of 4,4'-oxydiphthalic dianhydride (ODPA) and 29.4 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) were added to a 2 L separable flask. 131.2 g of 2-hydroxyethyl methacrylate (HEMA) and 400 mL of γ-butyrolactone were also added. Stirring was continued at room temperature. 81.5 g of pyridine was added while stirring to obtain a reaction mixture. After the exotherm caused by the reaction subsided, the reaction mixture was cooled to room temperature and allowed to stand for 16 hours.

Next, while stirring in an ice bath, a solution of 206.3 g of dicyclohexylcarbodiimide (DCC) dissolved in 200 mL of γ-butyrolactone was added to the reaction mixture over 20 minutes. Then, a solution of 93.0 g of 4,4'-oxydiphenylamine (ODA) suspended in 350 mL of γ-butyrolactone was added over 30 minutes while stirring. After stirring at room temperature for 4 hours, 30 mL of ethanol was added and stirred for 1 hour, followed by the addition of 400 mL of γ-butyrolactone. The resulting precipitate was removed by filtration to obtain a reaction solution.

The resulting reaction solution was added to 3 L of ethanol to produce a precipitate containing a crude polymer. The resulting crude polymer was separated by filtration and dissolved in 1.5 L of tetrahydrofuran to obtain a crude polymer solution. The resulting crude polymer solution was added dropwise to 28 L of water to precipitate the polymer. The resulting precipitate was separated by filtration and then vacuum-dried to obtain a powdered polymer (polyimide precursor A1). The molecular weight of polyimide precursor A1 was determined by gel permeation chromatography (based on standard polystyrene) and the weight-average molecular weight (Mw) was 24,000.

Preparation Example 2: (A) Synthesis of Polyimide Precursor A2

A polymer (polyimide precursor A2) was obtained by the same method as described in Preparation Example 1, except that 147.1 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) was used in place of 124.0 g of 4,4'-oxydiphthalic dianhydride (ODPA) and 29.4 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA). The molecular weight of polyimide precursor A2 was determined by gel permeation chromatography (based on standard polystyrene) to have a weight-average molecular weight (Mw) of 24,000.

Preparation Example 3: (A) Synthesis of Polyimide Precursor A3

A polymer (polyimide precursor A3) was obtained by the same method as described in Preparation Example 1, except that 155.1 g of 4,4'-oxyphthalic anhydride (ODPA) was used in place of 124.0 g of 4,4'-oxyphthalic anhydride (ODPA) and 29.4 g of 3,3',4,4'-biphenyltetracarboxylic anhydride (BPDA). The molecular weight of polyimide precursor A3 was measured by gel permeation chromatography (based on standard polystyrene) and the weight average molecular weight (Mw) was 21,000.

Preparation Example 4: (A) Synthesis of Polyimide Precursor A4

The reaction was carried out in the same manner as in Preparation Example 1, except that 98.6 g of 2,2'-dimethylbiphenyl-4,4'-diamine (m-TB) was used in place of 93.0 g of 4,4'-oxydianiline (ODA) in Preparation Example 3. Polymer (A4) was obtained. The molecular weight of polymer (A4) was measured by gel permeation chromatography (based on standard polystyrene) and the weight average molecular weight (Mw) was 21,000.

Preparation Example 5: (A) Synthesis of Polyimide Precursor A5

The reaction was carried out in the same manner as in Preparation Example 1, except that 48.1 g of p-phenylenediamine (p-PD) was used in place of 93.0 g of 4,4'-oxydianiline (ODA) in Preparation Example 3. Polymer (A5) was obtained. The molecular weight of Polymer (A5) was measured by gel permeation chromatography (based on standard polystyrene) and the weight average molecular weight (Mw) was 19,000.

Preparation Example 6: (A) Synthesis of Polyimide Precursor A6

The reaction was carried out in the same manner as in Preparation Example 1, except that 62.0 g of 4,4'-oxyphthalic dianhydride (ODPA) and 65.4 g of pyromellitic dianhydride (PMDA) were used in place of 155.1 g of 4,4'-oxyphthalic dianhydride (ODPA) in Preparation Example 4. Polymer (A6) was obtained. The molecular weight of Polymer (A6) was measured by gel permeation chromatography (based on standard polystyrene) and the weight average molecular weight (Mw) was 20,000.

Preparation Example 7: (A) Synthesis of Polyimide Precursor A7

The reaction was carried out in the same manner as in Preparation Example 1, except that 182.5 g of 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) was used in place of 93.0 g of 4,4'-oxydianiline (ODA) in Preparation Example 3. Polymer (A7) was obtained. The molecular weight of polymer (A7) was measured by gel permeation chromatography (based on standard polystyrene) and the weight average molecular weight (Mw) was 25,000.

Preparation Example 8: (A) Synthesis of Polyimide Precursor A8

The reaction was carried out in the same manner as in Preparation Example 1, except that 260.3 g of 4,4'-(4,4'-isopropylidenediphenoxy)phthalic dianhydride (BPADA) was used in place of 155.1 g of 4,4'-oxyphthalic dianhydride (ODPA) in Preparation Example 4. Polymer (A8) was obtained. The molecular weight of Polymer (A8) was measured by gel permeation chromatography (based on standard polystyrene) and the weight-average molecular weight (Mw) was 25,000.

Preparation Example 9: (A) Synthesis of Polyimide A9

To a 3 L separable glass flask equipped with a stirring device and a stirring paddle was added 64.1 g (0.20 mol) of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB), 97.7 g (0.22 mol) of 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA), and 500 g of DMAc. The mixture was stirred to dissolve TFMB and 6FDA in the DMAc. Polymerization was then carried out under a nitrogen flow at room temperature with continuous stirring for 12 hours to obtain a polyamide solution.

After adding 16g of pyridine to the resulting polyimide solution, 82g of acetic anhydride was added dropwise at room temperature. The solution was then stirred for 24 hours while maintaining the temperature between 20-100°C to allow the imidization reaction to proceed, yielding a polyimide solution.

In a 5-liter container, the resulting polyimide solution was added to 1,000 g of methanol while stirring to precipitate the polyimide resin. The solid polyimide resin was then filtered using a vacuum filter and washed with 1,000 g of methanol. The solution was then dried in a vacuum dryer at 100°C for 24 hours and then at 200°C for 3 hours. This yielded a polyimide powder containing terminal anhydride groups, polymer (A-11). The molecular weight of polymer A-11 was determined by gel permeation chromatography (based on standard polystyrene) to have a weight-average molecular weight (Mw) of 25,000.

<Example 1>

A photosensitive resin composition was prepared using polyimide precursor A1 by the following method and evaluated. (A) Resin A1 (100 g), (B) Flavonoid B1 (10 g of quercetin hydrate (Tokyo Chemical Industry Co., Ltd.), (C) Photopolymerization Initiator C1 (3 g of TR-PBG-3057 (TRONLY Co., Ltd.), and (C) Radical Polymerization Compound NK ESTER A-9300 (Shin-Nakamura Chemical Industry Co., Ltd.) (40 g) were dissolved in a mixed solvent of 80 g of γ-butyrolactone (GBL, Mitsubishi Chemical Corporation) and 20 g of dimethyl sulfoxide (DMSO, Toray Fine Chemical Co., Ltd.). The viscosity of the resulting solution was adjusted to approximately 40 poise by adding the necessary amount of a GBL:DMSO solution (80:20) to prepare a photosensitive resin composition. This composition was evaluated according to the above method. The results are shown in Table 1.

<Examples 2-18, Comparative Examples 1-4>

A photosensitive resin composition similar to that of Example 1 was prepared, except that the formulation ratios shown in Table 1 were used, and the same evaluations as in Example 1 were performed. The results are shown in Table 1. The (A) resins and (B) flavonoids listed in Table 1 are as follows.

A1: Polyimide precursor described in Preparation Example 1

A2: Polyimide precursor described in Preparation Example 2

A3: Polyimide precursor described in Preparation Example 3

A4: Polyimide precursor described in Preparation Example 4

A5: Polyimide precursor described in Preparation Example 5

A6: Polyimide precursor described in Preparation Example 6

A7: Polyimide precursor described in Preparation Example 7

A8: Polyimide precursor described in Preparation Example 8

A9: Polyimide described in Preparation Example 9

B1: Pyrrolidone Hydrate (manufactured by Tokyo Chemical Industry Co., Ltd.)

B2: Atractylodes lanceolate (manufactured by Tokyo Chemical Industry Co., Ltd.)

B3: Flavonoids (manufactured by Tokyo Chemical Industry Co., Ltd.)

B4: Hesperidin (manufactured by Tokyo Chemical Industry Co., Ltd.)

B5: Naringenin (manufactured by Tokyo Chemical Industry Co., Ltd.)

B1': 7-Hydroxyflavone (manufactured by Tokyo Chemical Industry Co., Ltd.)

B2': 3',4'-dihydroxyflavone (manufactured by Tokyo Chemical Industry Co., Ltd.)

B3': Curcumin (manufactured by Tokyo Chemical Industry Co., Ltd.)

B4': (+)-Catechin hydrate (manufactured by Tokyo Chemical Industry Co., Ltd.)

As shown in Table 1, the negative photosensitive resin composition of Example 1 received an A rating for copper adhesion and an A rating for copper porosity. The photosensitive resin compositions of Examples 2-15 all received ratings of B or higher for copper adhesion, copper porosity, and storage stability. Meanwhile, Comparative Example 1 received a C rating for copper adhesion, copper porosity, and storage stability, while Comparative Examples 2-5 received a C rating for copper adhesion.

[Industrial Availability]

The photosensitive resin composition of the present invention can achieve a hardened relief pattern with excellent copper adhesion, copper porosity suppression, and preservation stability. The present invention is particularly suitable for use in the field of photosensitive materials useful in the manufacture of electrical and electronic materials, such as semiconductor devices and multilayer wiring boards.

Claims (14)

A negative photosensitive resin composition is characterized by comprising the following components: (A) at least one resin selected from (A2) polyimide, (B) at least one flavonoid represented by the following general formula (1) or (1-2), (In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group;) (C) a photopolymerization initiator; and (D) a solvent. The content of the flavonoid (B) is 3-20 parts by mass relative to 100 parts by mass of the resin (A). A negative photosensitive resin composition is characterized by comprising the following components: (A) at least one resin selected from (A1) a polyimide precursor and (A2) a polyimide, (B) at least one flavonoid represented by the following general formula (1) or (1-2), excluding quercetin and gossypol flavonoids, (In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group;) (C) a photopolymerization initiator; and (D) a solvent. The content of the flavonoid (B) is 3-20 parts by mass relative to 100 parts by mass of the resin (A). A negative photosensitive resin composition is characterized by comprising the following components: (A) at least one resin selected from (A1) a polyimide precursor and (A2) a polyimide, (B) at least one flavonoid represented by the following general formula (1) or (1-2), (In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents; _R2 is a hydrogen atom or a hydroxyl group; _R3 - _R6 are groups selected from hydrogen atom, hydroxyl group, or methoxy group, and at least one of _R3 - _R6 is a hydroxyl group;) (C) a photopolymerization initiator; and (D) a solvent. The content of the flavonoid (B) is 10-20 parts by mass relative to 100 parts by mass of the resin (A). The negative photosensitive resin composition of any one of claims 1 to 3, wherein the flavonoid (B) is a compound represented by the following general formula (2): (Wherein, _n1 is an integer from 1 to 3, _n2 is 0 or 1, and _n3 is an integer from 1 to 2). The negative photosensitive resin composition of claim 4, wherein the flavonoid (B) is a compound represented by the following general formula (3): (where _n4 is 2 or 3, and _n5 is 1 or 2). The negative photosensitive resin composition of claim 4, wherein the flavonoid (B) is a compound represented by the following general formula (4): (where _n4 is 2 or 3). The negative photosensitive resin composition of any one of claims 1 to 3, wherein the flavonoid (B) is a compound represented by the following general formula (2-2): (wherein _n2 is 0 or 1, and _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents). The negative photosensitive resin composition of claim 7, wherein the flavonoid (B) is a compound represented by the following general formula (3-2): (In the formula, _R1 is an aromatic group having at least one hydroxyl group, which may further have other substituents). The negative photosensitive resin composition of claim 2 or 3, wherein the polyimide precursor (A1) comprises a polyimide precursor having a structural unit represented by the following general formula (5): {In formula (5), X ₁ is a tetravalent organic group, Y ₁ is a divalent organic group, n ₁ is an integer from 2 to 150, and R ₁₁ and R ₁₂ are each independently a hydrogen atom or a monovalent organic group}. The negative photosensitive resin composition of claim 9, wherein in the general formula (5), at least one of R ₁₁ and R ₁₂ has a structural unit represented by the following general formula (6): {In formula (6), L ₁ , L ₂ , and L ₃ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and m ₁ is an integer of 2 to 10}. The negative photosensitive resin composition according to any one of claims 1 to 3, wherein the negative photosensitive resin composition is a negative photosensitive resin composition for forming an interlayer insulating film. A method for producing a hardened relief pattern comprises the following steps: (1) applying a negative photosensitive resin composition as described in any one of claims 1 to 11 on a substrate to form a photosensitive resin layer on the substrate; (2) exposing the photosensitive resin layer; (3) developing the exposed photosensitive resin layer to form a relief pattern; and (4) heating the relief pattern to form a hardened relief pattern. The method for manufacturing a hardened relief pattern as claimed in claim 12, wherein the heat treatment in step (4) is a heat treatment below 230°C. A method for producing polyimide, comprising hardening the negative photosensitive resin composition according to any one of claims 1 to 11.