JP2022142745A - Bismaleimide compound, composition comprising the compound, polybenzoxazole, and semiconductor device - Google Patents

Abstract

To provide: a novel photosensitive resin precursor that can undergo alkali development, can undergo ring closure even at a low temperature, and preferably has excellent heat characteristics and electrical characteristics after curing; and use thereof.SOLUTION: Disclosed are: a bismaleimide compound having two partial structures in a molecule, in which partial structure a carbon atom having a substituent represented by the following formula (A) (in the formula, Y represents a direct bond or a divalent linking group) and a carbon atom having a hydroxyl group are directly bonded; a polymer which is a self-polymerized polymer of the bismaleimide compound; and benzoxazole which is an intramolecular dehydration cyclization product of the polymer.SELECTED DRAWING: None

Description

<Cross reference to related applications>
This application claims priority to Japanese Patent Application No. 2021-042386 filed with the Japan Patent Office on March 16, 2021, which is incorporated herein by reference in its entirety.
The present invention relates to a bismaleimide compound, a composition using the same, polybenzoxazole, and a semiconductor device. The bismaleimide compound of the present invention can be applied to protective films for semiconductor elements, interlayer insulating films, insulating films for rewiring layers, and the like.

Conventionally, polyimide resins, polybenzoxazole resins, and the like, which are excellent in heat resistance and mechanical properties, have been widely used for surface protective films, interlayer insulating films, and the like of semiconductor devices (Patent Document 1). When a polyimide resin or polybenzoxazole resin is used as a surface protective film or an interlayer insulating film, a method of forming through holes or the like by etching using a positive photoresist containing these resins is known. However, this method has the problem that it requires complicated steps such as coating and stripping of the photoresist. Therefore, for the purpose of streamlining the work process, studies have been made on heat-resistant materials imparted with photosensitivity (Patent Document 2).

Thin films of polyimide resins and polybenzoxazole resins, which have excellent heat resistance and mechanical properties, are generally obtained by thermally dehydrating and ring-closing coating films of their precursors. Requires firing at However, next-generation memories such as MRAMs (Magnetoresistive Random Access Memories) and resins used for encapsulating these memories are vulnerable to high temperatures. Therefore, the polyimide resin and polybenzoxazole resin used for the interlayer insulating film of the fan-out wafer level package that forms the rewiring structure on the surface protection film of such an element and the sealing resin have a low temperature of about 300° C. or less. It is required that the material be hardened by baking at 100°C and that various properties comparable to those obtained when conventional materials are baked at a high temperature of around 350°C can be obtained.

In addition, conventionally used polyimide resins require the use of large amounts of organic solvents such as N-methyl-2-pyrrolidone in the development process, resulting in higher costs. Therefore, not only the need for cost reduction but also safety and recent environmental concerns have led to demands for elimination of organic solvents. On the other hand, similar to photoresist, a method using various heat-resistant resin materials that can be developed (patterned) with a dilute alkaline aqueous solution, for example, polyamic acid and an amino group, an amide group, or a urethane group. A method of mixing compounds and heating after exposure in the presence of a photoinitiator (Patent Document 3), a method of mixing quinonediazide with a salt of polyamic acid and an amine compound having a phenolic hydroxyl group (Patent Document 4), polyamide A method of mixing an acid and a base generator such as nifedipine has been proposed (Patent Document 5).
All of these methods use a positive photosensitive composition based on polyamic acid. Although such a photosensitive composition exhibits relatively good developability, the solubility difference between the exposed area and the unexposed area is small, resulting in large pattern film loss and insufficient photosensitivity. In addition, since these compositions contain a large amount of free carboxylic acid in the polymer main chain, the acidity of the polymer itself hydrolyzes the main chain over time, resulting in extremely low storage stability. be.

Patent Document 6 discloses a negative film in which a hydroxyl group derived from an epoxy ring generated when a photosensitive group is introduced via an ester bond by reacting glycidyl methacrylate on a carboxyl group of a polyamic acid is blocked with an intramolecular cyclic acid anhydride. type photosensitive materials have been proposed. However, since the photosensitive material of this document also contains a large amount of free carboxylic acid in the polymer, there is concern that storage stability is low due to the effects of hydrolysis over time of the main chain and photosensitive side chain; However, in such a photosensitive material, the imidization reaction proceeds due to heating during the introduction of the photosensitive group, and there are various problems such that the desired polymer cannot be obtained.

Furthermore, the data communication volume of communication terminals typified by smartphones is steadily increasing, and communication frequencies are becoming higher in order to transmit the amount of data in a short time. In order to increase the communication frequency, it is necessary to suppress transmission loss, and materials having a low dielectric constant and a low dielectric loss tangent are required. However, it has been difficult to achieve both the properties and dielectric properties mentioned above.

JP-A-11-199557 JP-A-11-24271 JP-A-6-289626 JP-A-6-161102 JP-A-5-5995 Japanese Patent Publication No. 2-37934

An object of the present invention is to provide novel bismaleimide compounds.
A further object of the present invention is to provide compositions, polybenzoxazoles and semiconductor devices containing said novel compounds.
Still another object of the present invention is to provide a cured film (preferably thermal properties and electrical It is an object of the present invention to provide a compound capable of obtaining a cured film having excellent properties.

As a result of intensive studies by the present inventors, it was found that heat treatment at a low temperature of 300 ° C. or less (or light It was found that a cured film can be obtained even by irradiation and heat treatment at 300° C. or less.

（式中、Ｙは直接結合又は二価の連結基を表す。）
で表される置換基を有する炭素原子と、
水酸基を有する炭素原子とが直接結合した部分構造を、一分子中に二つ有するビスマレイミド化合物。
［２］．
下記式（１）

（式中、環ａはベンゼン環又はシクロヘキサン環を表す。Ｘ及びＹはそれぞれ独立に直接結合又は二価の連結基を表し、複数存在するＹは互いに同じでも異なってもよい。Ｚは環ａに結合した一価の置換基を表し、Ｚが複数存在する場合、それぞれのＺは互いに同じでも異なってもよい。Ｌ及びＭは置換基Ｚの数であって、それぞれ独立に０乃至３の整数を表す。）
で表される、前項［１］に記載のビスマレイミド化合物。
［３］．
Ｘが直接結合、又は炭素原子、フッ素原子、硫黄原子及び酸素原子からなる群より選択される一種以上を含む二価の連結基である、前項［２］に記載のビスマレイミド化合物。
［４］．
Ｘが直接結合、又は下記式（ａ）乃至（ｆ）

のいずれかで表される二価の連結基である、前項［３］に記載のビスマレイミド化合物。
［５］．
Ｙが炭素数１乃至１１のアルキレン基、又は二価の芳香族基を含む炭素数１乃至１１のアルキレン基である、前項［１］乃至［４］のいずれか一項に記載のビスマレイミド化合物。
［６］．
前項［１］乃至［５］のいずれか一項に記載のビスマレイミド化合物、及びマレイミド基と反応し得る化合物を含有する組成物。
［７］．
前項［１］乃至［５］のいずれか一項に記載のビスマレイミド化合物、及び光重合開始剤若しくは硬化触媒を含有する組成物。
［８］．
下記式（２）

（式中、Ｘ、Ｙ、Ｚ、Ｌ、Ｍ及び環ａは前項［１］に記載の式（１）におけるＸ、Ｙ、Ｚ、Ｌ、Ｍ及び環ａと同じ意味を表す。）
で表される構造単位を２乃至１５０個有する重合体であって、前項［２］乃至［５］のいずれか一項に記載のビスマレイミド化合物の自己重合物又は前項［６］に記載の組成物の共重合物である重合体。
［９］．
下記式（３）

（式中、Ｘ、Ｙ、Ｚ、Ｌ、Ｍ及び環ａは前項［１］に記載の式（１）におけるＸ、Ｙ、Ｚ、Ｌ、Ｍ及び環ａと同じ意味を表す。）
で表される構造単位を２乃至１５０個有するポリベンゾオキサゾールであって、前項［８］に記載の重合体の分子内脱水閉環物であるポリベンゾオキサゾール。
［１０］．
前項［９］に記載のポリベンゾオキサゾールを含む表面保護膜、層間絶縁膜、又は再配線層の絶縁膜を備える半導体素子。
［１１］．
前項［１］乃至［５］のいずれか一項に記載のビスマレイミド化合物及び光重合開始剤を含有する組成物を基材で挟み込んで得られるドライフィルムレジスト。 That is, aspects of the present invention are as follows.
[1].
Formula (A) below

(In the formula, Y represents a direct bond or a divalent linking group.)
A carbon atom having a substituent represented by
A bismaleimide compound having two partial structures in one molecule in which a carbon atom having a hydroxyl group is directly bonded.
[2].
Formula (1) below

(Wherein, ring a represents a benzene ring or a cyclohexane ring. X and Y each independently represent a direct bond or a divalent linking group, and multiple Y may be the same or different. Z is ring a represents a monovalent substituent attached to , and when there is more than one Z, each Z may be the same or different, L and M are the number of substituents Z, and each independently represents a number of 0 to 3 represents an integer.)
The bismaleimide compound according to the preceding item [1], represented by
[3].
The bismaleimide compound according to the preceding item [2], wherein X is a direct bond or a divalent linking group containing one or more selected from the group consisting of carbon atoms, fluorine atoms, sulfur atoms and oxygen atoms.
[4].
X is a direct bond, or the following formulas (a) to (f)

The bismaleimide compound according to the preceding item [3], which is a divalent linking group represented by any one of
[5].
The bismaleimide compound according to any one of [1] to [4] above, wherein Y is an alkylene group having 1 to 11 carbon atoms or an alkylene group having 1 to 11 carbon atoms containing a divalent aromatic group. .
[6].
A composition containing the bismaleimide compound according to any one of the preceding items [1] to [5] and a compound capable of reacting with a maleimide group.
[7].
A composition comprising the bismaleimide compound according to any one of [1] to [5] above, and a photopolymerization initiator or a curing catalyst.
[8].
Formula (2) below

(Wherein, X, Y, Z, L, M and ring a have the same meanings as X, Y, Z, L, M and ring a in formula (1) described in [1] above.)
A polymer having 2 to 150 structural units represented by the self-polymerization product of the bismaleimide compound according to any one of the preceding items [2] to [5] or the composition according to the preceding item [6] A polymer that is a copolymer of
[9].
Formula (3) below

(Wherein, X, Y, Z, L, M and ring a have the same meanings as X, Y, Z, L, M and ring a in formula (1) described in [1] above.)
A polybenzoxazole having 2 to 150 structural units represented by the above, which is an intramolecular dehydrated ring closure product of the polymer described in [8] above.
[10].
A semiconductor device comprising a surface protective film, an interlayer insulating film, or an insulating film of a rewiring layer containing the polybenzoxazole described in [9] above.
[11].
A dry film resist obtained by sandwiching a composition containing the bismaleimide compound according to any one of [1] to [5] above and a photopolymerization initiator between substrates.

The composition containing the compound of the present invention can be developed with an alkaline aqueous solution, and by using the composition, heat treatment at a low temperature of 300 ° C. or lower (or light irradiation and heat treatment at 300 ° C. or lower) can be performed. Even if there is, a cured film can be obtained. Also, the cured film according to the preferred embodiment of the present invention has excellent thermal properties and electrical properties.

Embodiments of the present invention will be described in detail below, but the present invention is not limited to these embodiments.
The bismaleimide compound of the present invention (hereinafter also simply referred to as "the compound of the present invention") has a partial structure in which a carbon atom having a substituent represented by the following formula (A) and a carbon atom having a hydroxyl group are directly bonded. is characterized by having two in one molecule.

In formula (A), Y represents a direct bond or a divalent linking group.
The divalent linking group represented by Y in formula (A) is not particularly limited, but is preferably an alkylene group having 1 to 11 carbon atoms or an alkylene group having 1 to 11 carbon atoms including a divalent aromatic group. Incidentally, the divalent alkylene group referred to here is not limited to a linear one, and may be a branched or cyclic divalent alkylene group.

From the viewpoint of film properties and solubility, the divalent linking group represented by Y in formula (A) is more preferably an alkylene group having 1 to 11 carbon atoms, more preferably an alkylene group having 2 to 8 carbon atoms. An alkylene group of number 5 or an alkylene group represented by the following formula (g) is particularly preferred, and an alkylene group represented by the following formula (g) is most preferred.
The direct bond represented by Y in the formula (A) means that the nitrogen atom in the maleimide ring and the carbon atom in the carbonyl group specified in the formula (A) are a direct single bond without any intervening atom or the like. It is a connected structure.

A direct bond between a carbon atom having a substituent represented by formula (A) and a carbon atom having a hydroxyl group may be a single bond, a double bond, or a carbon-carbon bond accompanied by resonance in an aromatic compound or the like.
The partial structure in which a carbon atom having a substituent represented by formula (A) and a carbon atom having a hydroxyl group are directly bonded by a single bond is a tetravalent linking group represented by the following formula (B), The partial structure in which a carbon atom having a substituent represented by formula (A) and a carbon atom having a hydroxyl group are directly bonded via a double bond is a divalent linking group represented by the following formula (C). . A partial structure in which a carbon atom having a substituent represented by formula (A) and a carbon atom having a hydroxyl group are directly bonded via a carbon-carbon bond accompanied by resonance is exemplified by the following formula (D). Ar in formula (D) is an aromatic ring.

A direct bond between a carbon atom having a substituent represented by formula (A) and a carbon atom having a hydroxyl group is preferably a single bond or a carbon-carbon bond accompanied by resonance in an aromatic compound or the like. When two adjacent carbon atoms on the cyclo ring have a substituent represented by formula (A) and a hydroxyl group, respectively, or two adjacent carbon atoms on the aromatic ring have a substituent represented by formula (A) and a hydroxyl group, respectively. When two adjacent carbon atoms on the cyclohexane ring have a substituent and a hydroxyl group represented by the formula (A), respectively, or the adjacent carbon atoms on the benzene ring have a substituent and a hydroxyl group represented by the formula (A) It is more preferable to have each That is, a preferred example of the compound of the present invention includes a compound represented by the following formula (1).

In formula (1), ring a represents a benzene ring or a cyclohexane ring. That is, the bismaleimide compound represented by formula (1) has a structure in which two benzene rings are directly bonded or bonded via a divalent linking group, or two cyclohexane rings are bonded directly or via a divalent linking group. It is a compound with a structure as a base skeleton.
In formula (1), X and Y each independently represent a direct bond or a divalent linking group, and multiple Y's may be the same or different.
The divalent linking group represented by X in formula (1) is not particularly limited. 2-diyl group, propane-2,2-diyl group (isopropylidene group), propane-1,3-diyl group, propane-2,3-diyl group, trifluoromethylmethanediyl group, di(trifluoromethyl) methanediyl group (hexafluoroisopropylidene group), sulfonyl group, fluorenyl group and the like.
The divalent linking group represented by X in formula (1) includes an oxygen atom, a methylene group (methanediyl group), an ethane-1,2-diyl group, an ethane-2,2- diyl group, propane-2,2-diyl group, propane-1,3-diyl group, propane-2,3-diyl group, trifluoromethylmethanediyl group, di(trifluoromethyl)methanediyl group, sulfonyl group or fluorenyl groups are preferred. It is more preferably an oxygen atom, a propane-2,2-diyl group, a di(trifluoromethyl)methanediyl group or a sulfonyl group, and still more preferably a di(trifluoromethyl)methanediyl group or a sulfonyl group.
X in formula (1) is preferably a direct bond or a divalent linking group containing one or more selected from the group consisting of carbon atoms, fluorine atoms, sulfur atoms and oxygen atoms. The term "a divalent linking group containing one or more selected from the group consisting of a carbon atom, a fluorine atom, a sulfur atom and an oxygen atom" as used herein means a divalent linking group containing one or more of these atoms. Although it is not particularly limited as long as it is, a divalent linking group represented by any one of the following formulas (a) to (f) is more preferable.
That is, X in formula (1) is more preferably a direct bond or a divalent linking group represented by any one of the following formulas (a) to (f).
The direct bond represented by X in Formula (1) is a structure in which two rings a specified in Formula (1) are directly linked by a single bond without any intervening atoms or the like.

Examples of the divalent linking group represented by Y in Formula (1) include the divalent linking group represented by Y in Formula (A). Moreover, the preferred divalent linking group represented by Y in formula (1) is also the same as the divalent linking group represented by Y in formula (A).

In formula (1), Z represents a monovalent substituent of the benzene ring or cyclohexane ring as ring a. That is, among the 6 carbon atoms on the benzene ring or cyclohexane ring which is ring a, the 3 carbon atoms not substituted with a substituent represented by formula (A), a hydroxyl group, or X have a substituent Z or attached to a hydrogen atom.
The monovalent substituent represented by Z is not particularly limited, but is halogen atom, hydroxyl group, nitro group, cyano group, aliphatic group, aromatic group, acetyl group, carboxyl group, ester group, amide group, trifluoromethyl group. , an imide group or a urea group. When there are multiple Zs, each Z may be the same or different. L and M are the numbers of substituents Z, each independently represents an integer of 0 to 3, preferably each independently an integer of 0 or 1.
Specific examples of the halogen atom, which is a preferred embodiment of Z in formula (1), include a fluorine atom, a bromine atom, a chlorine atom and an iodine atom. Among these, a fluorine atom is preferable.
An aliphatic group, which is a preferred embodiment of Z in formula (1), is a residue obtained by removing one hydrogen atom from a hydrocarbon compound having no aromaticity. The hydrocarbon compound is not limited to linear, branched or cyclic, and may be a compound having a plurality of these shapes.
Specific examples of the aliphatic group, which is a preferred embodiment of Z in formula (1), include alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, propyl and cyclohexane groups, and 1 to 6 carbon atoms such as propene. and alkynyl groups having 1 to 6 carbon atoms such as propyne. Among these, a methyl group is preferred.

An aromatic group, which is a preferred embodiment of Z in formula (1), is a residue obtained by removing one hydrogen atom from an aromatic ring of an aromatic compound. The aromatic compound is not limited to any aromatic hydrocarbon compound, heterocyclic compound, heterocyclic condensed aromatic compound, etc., as long as it is a compound having aromaticity.
Specific examples of the aromatic group, which is a preferred embodiment of Z in formula (1), include a phenyl group and a naphthyl group. Among these, a phenyl group is preferred.
Specific examples of the ester group, which is a preferred embodiment of Z in formula (1), include a methoxycarbonyl group, an ethoxycarbonyl group, an n-proxycarbonyl group, a benzyloxycarbonyl group and a phenoxycarbonyl group. Among these, a phenoxycarbonyl group is preferred.
Specific examples of the amide group, which is a preferred embodiment of Z in formula (1), include alkylamide groups such as —CONH ₂ , —CONH(CH ₃ ), —CONH(i—C ₃ H ₇ ); benzamide, naphthamide, and arylamide groups such as pt-butylbenzamide, o-chlorobenzamide and --CON(Ph) ₂ . Among these, benzamide is preferred. In addition, in this specification, Ph shows a phenyl group.
As Z in formula (1), an aliphatic group is more preferable from the viewpoint of ease of dehydration ring closure at low temperatures.

The method for producing the compound of the present invention is not particularly limited, but after converting maleimidecarboxylic acid into a halide derivative using a halogenating agent, the halide derivative is hydrogenated with a diaminodiphenol compound or a benzene ring of the diaminodiphenol compound. A common method is to react a cyclohexane ring compound (hereinafter referred to as a diaminodiphenol compound or a hydrogenated product thereof). In the reaction between the halide derivative and the diaminodiphenol compound or its hydrogenated product, it is preferable to use the halide derivative in an amount of 2 to 2 times the molar excess of the diaminodiphenol compound or its hydrogenated product.
A chloride derivative is preferable as the halide derivative. Halogenating agents used in converting maleimidocarboxylic acid to a chloride derivative include thionyl chloride, oxalyl chloride, phosphoryl chloride, phosphorus chloride, and the like, which are commonly used in acid chloride reactions.
In addition, maleimidocarboxylic acid may be synthesized from the amino acid by a known method, or a commercially available product may be used.

Examples of the maleimidocarboxylic acid used in producing the compound of the present invention include compound Nos. 1 to 4, but not limited to these. These maleimidocarboxylic acids can be used alone or in combination of two or more.

Examples of the diaminodiphenol compound or hydrogenated product thereof used in producing the compound of the present invention include the following compound Nos. 5 to 12, and compound no. Examples include, but are not limited to, cyclohexane ring compounds in which the benzene ring in 5 to 12 is hydrogenated. These diaminodiphenol compounds or hydrogenated products thereof can be used alone or in combination of two or more.

The reaction between the halide derivative and the diaminodiphenol compound or hydrogenated product thereof is desirably carried out in an organic solvent in the presence of a dehalogenating agent. Organic bases such as pyridine, picoline and triethylamine can be used as dehalogenating agents. As the organic solvent, sulfolane, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N,N-dimethylformamide, etc. can be used. The concentration of these reaction components in the entire reaction system including the solvent is not particularly limited, but is preferably 20 to 80% by mass, more preferably 40 to 60% by mass.
As a specific synthesis procedure, maleimide carboxylic acid is first dissolved in an organic solvent, and a halide derivative is synthesized using a halogenating agent. A diaminodiphenol compound or its hydrogenated form is then added in the presence of a dehalogenating agent. The temperature at which the diaminodiphenol compound or hydrogenated product thereof is added is preferably -20 to 25°C, more preferably 0 to 20°C. The reaction temperature of the halide derivative and the diaminodiphenol compound or its hydrogenation is preferably 0 to 80°C, more preferably 50 to 70°C. The reaction time is preferably 30 minutes to 24 hours, more preferably 1 to 8 hours. After completion of the reaction, the target compound can be obtained by adding water to the obtained reaction solution.
Impurities can be removed by using an acidic aqueous solution, an alkaline aqueous solution, a neutral aqueous solution, an organic solvent, or the like from the compound obtained by the above procedure.

Next, the polymer of the present invention will be explained.
The compound represented by the formula (1) of the present invention is a polymer (self-polymerized product) obtained by self-polymerizing the compound represented by the formula (1) via maleimide groups at both ends, or the compound represented by the formula (1) A polymer (copolymer) obtained by copolymerizing a compound represented by and a compound capable of reacting with a maleimide group, and the polymer of the present invention having a structural unit represented by the following formula (2). can. That is, the self-polymerized product has a structure in which unit structures represented by the following formula (2) are directly bonded. Further, the above-mentioned copolymer has a structure in which unit structures represented by the following formula (2) are bonded via a linking group other than the formula (2). Although the number of unit structures represented by formula (2) in the polymer of the present invention is not particularly limited, it is preferably 2 to 150.
X, Y, Z, L, M and ring a in the unit structure represented by formula (2) have the same meanings as X, Y, Z, L, M and ring a in formula (1). , and preferable ones are the same as those in formula (1).

The compound represented by the formula (1) can be self-polymerized by heating at 40 to 150° C. for about 30 to 300 minutes. The conditions for self-polymerization are not particularly limited as long as they are the conditions normally used for reacting maleimide groups with each other. Under relatively moderate heating conditions, for example, at 50 to 70° C. for about 60 to 180 minutes, the compound represented by formula (1) containing the compound represented by formula (1) as a main component and the self-polymerized product is obtained, and under relatively severe heating conditions, such as 80 to 120 ° C. for 30 to 120 minutes, the compound represented by formula (1) containing the self-polymer as the main component and the self-polymer A mixture of The ratio of the compound represented by the formula (1) and the self-polymerized product in the mixture affects handling and the like when subjected to subsequent steps, so the ratio (reaction conditions) of the two should be selected in consideration of handling and the like. Just do it.
Even in a mixture containing the compound represented by formula (1) as a main component, a self-polymerization reaction also occurs due to heating during the ring closure reaction for benzimidazolization. Therefore, such component composition of the mixture is unlikely to have an undesirable effect on the physical properties of the final polybenzimidazole.

Although the compound represented by formula (1) can self-polymerize alone, it can also be self-polymerized after forming a composition by using a photopolymerization initiator or a curing catalyst in combination with the compound represented by formula (1). . By using a photopolymerization initiator together, it becomes possible to cause self-polymerization by light irradiation. Also, by using a curing catalyst in combination, the heating temperature during self-polymerization can be made lower than when not in use.

A photopolymerization initiator that can be used in combination for self-polymerization is not particularly limited, and conventionally used photopolymerization initiators can be appropriately employed. Specific examples of photopolymerization initiators include acetophenone, 2,2-dimethoxyacetophenone, p-dimethylaminoacetophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, and benzoin. isopropyl ether, benzoin n-butyl ether, benzyl dimethyl ketal, thioxatone, 2-chlorothioxazone, 2-methylthioxatone, 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl- Phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1 -one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2-methyl-1-[4 -(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2,4,6-trimethylbenzoyl-diphenyl- Phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 1-[4-(phenylthio)phenyl]-1,2-octanedione = 2-(O-benzoyloxime), 1- [9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyloxime), 2,4-diethylthioxanthone and the like. These photopolymerization initiators may be used singly or in combination of two or more.

Among these, the exposure wavelength of 310 is preferred from the viewpoint that fine patterns can be formed using a reduction projection exposure machine (stepper; light source wavelength: 365 nm, 436 nm) that is standardly used in the manufacturing process of semiconductor protective films and the like. It is preferable to use one that efficiently generates radicals in the range of 436 nm to 436 nm (more preferably 365 nm). Preferred photopolymerization initiators include, for example, 1-[4-(phenylthio)phenyl]-1,2-octanedione=2-(O-benzoyloxime) (manufactured by BASF Japan, "IRGACURE OXE-01"), 1 -[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyloxime) (manufactured by BASF Japan, "IRGACURE OXE-02"), 2,4-diethyl Thioxanthone (manufactured by Nippon Kayaku Co., Ltd., "DETX-S"), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (manufactured by IGM Resins B.V., "Omirad 907”).
The amount of the photopolymerization initiator (when it is used) is preferably 0.1 to 20 parts by mass, more preferably 1 to 5 parts by mass, relative to 100 parts by mass of the compound represented by formula (1). be.

A photopolymerization initiator may be used in combination with a sensitizer. The sensitizer that can be used in combination is not particularly limited as long as it is conventionally known, and examples include 4,4'-bis(diethylamino)benzophenone.
The amount of the sensitizer used (when it is used) is preferably 2 parts by mass or less, more preferably 0.05 to 0.5 parts by mass, relative to 100 parts by mass of the compound represented by formula (1). . By using a sensitizer together, the sensitivity to light during self-polymerization can be enhanced.

The curing catalyst that can be used in combination for self-polymerization is not particularly limited as long as it can accelerate the self-polymerization of the maleimide groups at both ends of the compound represented by the formula (1) of the present invention by heating. Any one that is used can be used as appropriate. Specific examples of curing catalysts include 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole and 1-cyanoethyl-2-ethyl-4-methylimidazole. imidazoles such as triethylamine, triethylenediamine, 2-(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)undecene-7, tris(dimethylaminomethyl)phenol and benzyldimethylamine Amines, phosphines such as triphenylphosphine, tributylphosphine and trioctylphosphine, organometallic salts such as tin octylate, zinc octylate, dibutyltin dimaleate, zinc naphthenate, cobalt naphthenate and tin oleate, zinc chloride , metal chlorides such as aluminum chloride and tin chloride, organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide, azo compounds such as azobisisobutyronitrile and azobisdimethylvaleronitrile, hydrochloric acid, mineral acids such as sulfuric acid and phosphoric acid; Lewis acids such as boron trifluoride; and salts such as sodium carbonate and lithium chloride.
The amount of the curing catalyst (when it is used) is preferably 10 parts by weight or less, more preferably 1 to 5 parts by weight, per 100 parts by weight of the compound represented by formula (1).

Compounds capable of reacting with maleimide groups used for copolymerization with the compound represented by formula (1) include compounds having a plurality of unsaturated double bonds such as acryl groups, methacryl groups, allyl groups and styryl groups. be done. Copolymerization by photoirradiation using these compounds in combination is a preferred mode because the sensitivity to light can be increased, and polyfunctional acrylates are more preferred because the crosslinking reaction by photopolymerization is easy.

Specific examples of compounds having a plurality of acrylic groups include hydrogenated dicyclopentadienyl diacrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, Acrylates, 1,6-hexanediol diacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, polyethylene glycol 200 diacrylate, polyethylene glycol 400 diacrylate, polyethylene glycol 600 diacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, hydroxy Pivalic acid ester neopentyl glycol diacrylate, triethylene glycol diacrylate, bis(acryloxyethoxy)bisphenol A, bis(acryloxyethoxy)tetrabromobisphenol A, tripropylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate acrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate and the like.

Specific examples of the compound having a plurality of methacrylic groups include compounds in which the acryl groups in the compound having a plurality of acryl groups are replaced with methacrylic groups.
Specific examples of compounds having multiple allyl groups include diallyl adipate, diallyl fumarate, diallyl hexahydrophthalate, pentaerythritol tetraallyl ether, glycerol diallyl ether, and triallyl citrate.
Specific examples of compounds having multiple styryl groups include bis(vinylphenyl)methane, bis(vinylphenyl)ethane, and bis(vinylphenyl)hexane.

The ratio of the compound represented by the formula (1) used for copolymerization and the compound capable of reacting with the maleimide group is not particularly limited, but may be appropriately determined depending on the molecular weight of the compound capable of reacting with the maleimide group, the number of polymerizable functional groups, etc. can be adjusted. For example, the amount of the compound capable of reacting with maleimide groups is preferably 0.01 to 10 mol, more preferably 0.1 to 1 mol, per 1 mol of the compound represented by formula (1).
The copolymerization may be carried out under the various conditions for self-polymerization described above, and may be carried out in combination with a photopolymerization initiator, a sensitizer and a curing catalyst. Their usage is the same as described in the self-polymerization section.

The polybenzoxazole of the present invention is an intramolecular dehydrated ring closure product of the above polymer (self-polymer and copolymer) of the present invention, and has a unit structure represented by the following formula (3).
X, Y, Z, L, M and ring a in the unit structure represented by formula (3) have the same meanings as X, Y, Z, L, M and ring a in formula (1). , and preferable ones are the same as those in formula (1).
Throughout this specification and the appended claims, not only when ring a is a benzene ring but also when the benzene ring is hydrogenated to form a cyclohexane ring, the formula (3 ) are collectively referred to as "polybenzoxazole".

Conditions for the dehydration ring-closure of the polymer of the present invention are not particularly limited as long as they are the conditions normally used for converting a benzoxazole precursor into benzoxazole by dehydration ring-closure reaction. The dehydration ring-closure reaction can be carried out, for example, by using a hot plate, an oven, or a temperature-programmable oven. Air may be used as the atmospheric gas for thermal conversion, or an inert gas such as nitrogen or argon may be used.
The dehydration ring closure reaction of the polymers of the present invention can advantageously be carried out at low temperatures of 300°C or less. The temperature of the dehydration ring closure reaction may be preferably less than 300°C, more preferably 290°C or less.

The composition of the present invention is a bismaleimide compound having two partial structures in one molecule in which a carbon atom having a substituent represented by the formula (A) and a carbon atom having a hydroxyl group are directly bonded, or a bismaleimide compound represented by the formula (1 ) may contain components other than the bismaleimide compound represented by . Other components that may be contained in the composition of the present invention include, for example, organic solvents, photopolymerization initiators, thermoplastic resins, colorants, thickeners, thermal polymerization inhibitors, antifoaming agents, leveling agents, and maleimide groups. A curing agent or curing catalyst having a reactive group, or an adhesion enhancer such as a coupling agent may be used. Various components other than those described above can also be used without particular limitation, depending on the application and usage of the composition. A composition containing an organic solvent is preferred because it is easy to handle.
In addition, since the compound of the present invention is capable of self-polymerization, it can be used without using a photopolymerization initiator, a curing agent, a curing catalyst, or the like.

The curing agent is not particularly limited, and conventionally used compounds can be appropriately employed. The curing agent is not particularly limited as long as it has a functional group (or structure) capable of cross-linking reaction with a maleimide group such as an amino group, a cyanate group, a phenolic hydroxyl group or an alcoholic hydroxyl group. A bismaleimide compound other than the bismaleimide compound of the present invention may be used in combination.

Examples of organic solvents include, but are not limited to, γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, benzyl acetate, n-butyl acetate, ethoxyethylpropionate, 3-methylmethoxypropionate, N-methyl- 2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphorylamide, tetramethylenesulfone, cyclohexanone, cyclopentanone, diethylketone, diisobutylketone and and methyl amyl ketone. These organic solvents can be used alone or in combination of two or more. Combined use of an organic solvent is a preferred embodiment from the viewpoint of improving the handling of the composition.
The content of the organic solvent in the composition of the present invention is not particularly limited, but is usually 95% by mass or less, preferably 20 to 90% by mass, based on the total weight of the composition.

The coupling agent is not particularly limited, but typically may be a silane coupling agent. Silane coupling agents include, but are not limited to, 3-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyl-tris(2-methoxyethoxy)silane, and 3-methacryloxypropyl. trimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2-( aminoethyl)-3-aminopropyltrimethoxysilane and 3-ureidopropyltriethoxysilane. These can be used individually or in combination of 2 or more types.
Since the silane coupling agent is unreactive with the compound of the present invention (compound, self-polymerized product, polybenzoxazole), components other than those acting at the substrate interface should be present as residual components after curing. can be Therefore, if the adhesion enhancer is used in a large amount, it may have undesirable effects such as deterioration of physical properties. Depending on the type of base material, even a small amount can be effective, so it is appropriate to use it within a range that does not cause undesirable effects. The usage ratio is usually 15% by mass or less, preferably more than 0% by mass and 5% by mass or less, based on the total weight of the composition, but the upper limit of the usage ratio may vary depending on the type of substrate.

Examples of thermoplastic resins include polyethersulfone, polystyrene, and polycarbonate.
Examples of coloring agents include phthalocyanine blue, phthalocyanine green, iodine green, crystal violet, titanium oxide, carbon black and naphthalene black.
Examples of thickeners include orben, bentone, montmorillonite, and the like.
Thermal polymerization inhibitors include, for example, hydroquinone and 2,6-di-tert-butyl-p-methylphenol.
Antifoaming agents include, for example, silicone-based, fluorine-based, and polymer-based antifoaming agents.
The amount of these additives used (when they are used) in the composition of the present invention is, for example, preferably 30% by mass or less, but can be appropriately increased or decreased depending on the purpose of use.

Inorganic fillers such as barium sulfate, barium titanate, silicon oxide, amorphous silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica powder are used in combination with the composition of the present invention. may The proportion of the inorganic filler (if used) is preferably 60% by mass or less in the composition of the present invention.

A cured film of a heat-resistant resin formed from the polybenzoxazole of the present invention can be used for electronic parts such as semiconductor devices and multilayer wiring boards, and for organic EL displays. Specifically, this cured film is used as a passivation film for semiconductors, a surface protection film for semiconductor elements, an interlayer insulation film, an interlayer insulation film for multilayer wiring for high-density mounting, an insulation film for rewiring layers, an inductor, a SAW filter, and the like. Although it is suitably used for applications such as interlayer insulating films of electronic parts, insulating films and flat layers of organic electroluminescent elements, it is not limited to this, and various structures can be employed.

The compounds and compositions of the invention can also be used in the form of dry film resists. That is, the compound and composition of the present invention were applied onto a base film using a roll coater, die coater, knife coater, bar coater, gravure coater, etc., and then the temperature was set to 45 to 140°C. A dry film resist can be obtained by drying in a drying oven to remove a predetermined amount of solvent, and by laminating a cover film or the like as necessary. At this time, the thickness of the resist on the base film is adjusted to 2 to 200 μm. Films such as polyester, polypropylene, polyethylene, TAC, and polyimide are used as the base film and the cover film. For these films, films treated with a silicone release agent or a non-silicone release agent may be used as necessary. If it is supplied as a dry film resist, the steps of coating on a support and drying can be omitted, and the composition of the present invention can be used more simply.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. "Parts" and "%" in the examples are based on mass.

Example 1 <Synthesis of compound (compound A-1) represented by general formula (1)>
A 500 ml round bottom flask equipped with a Teflon-coated stir bar was charged with 6.76 parts (0.040 mol) of 3-maleimidopropionic acid (compound No. 1 above) and 20 parts DMF. After cooling the mixture with ice, 10.15 parts (0.080 mol) of oxalyl chloride was slowly added, and the mixture was stirred at room temperature for 2 hours. Then, 7.33 parts (0.020 mol) of 4,4'-(hexafluoroisopropylidene)bis(2-aminophenol) (the compound of No. 5 above) dissolved in 10 parts of DMF was added, and the mixture was stirred at 60°C for 3 hours. Stirred for an hour. After cooling to room temperature, 300 parts of water was added and the precipitated solid was collected by filtration. The solid obtained above was dissolved in 30 parts of cyclopentanone, washed with 10 parts of dilute hydrochloric acid and then with 10 parts of water to remove unreacted raw materials, and the organic layer was concentrated under vacuum to yield compound A-1. 5.3 parts of solution (solid content 40%) was obtained (yield 16%).

Example 2 <Synthesis of compound (compound A-2) represented by general formula (1)>
A 500 ml round bottom flask equipped with a Teflon-coated stir bar was charged with 8.44 parts (0.040 mol) of 6-maleimidohexanoic acid (compound No. 2 above) and 20 parts DMF. After cooling the mixture with ice, 10.15 parts (0.080 mol) of oxalyl chloride was slowly added, and the mixture was stirred at room temperature for 2 hours. Then, 7.33 parts (0.020 mol) of 4,4'-(hexafluoroisopropylidene)bis(2-aminophenol) (the compound of No. 5 above) dissolved in 10 parts of DMF was added, and the mixture was stirred at 60°C for 3 hours. Stirred for an hour. After cooling to room temperature, 300 parts of water was added and the precipitated solid was collected by filtration. The solid obtained above and 100 parts of methanol were placed in a flask and washed with stirring at 40° C., then cyclopentanone was added and concentrated under vacuum to obtain a compound A-2 solution (68% solid content) of 22.5%. (yield 47%).

Example 3 <Synthesis of compound (compound A-3) represented by general formula (1)>
Into a 500 ml round-bottomed flask equipped with a Teflon-coated stir bar, 9.50 parts of 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid (compound No. 4 above) (0.50 parts) are added. 040 mol), and 20 parts of DMF were added. After cooling the mixture with ice, 10.15 parts (0.080 mol) of oxalyl chloride was slowly added, and the mixture was stirred at room temperature for 2 hours. Then, 7.33 parts (0.020 mol) of 4,4'-(hexafluoroisopropylidene)bis(2-aminophenol) (the compound of No. 5 above) dissolved in 10 parts of DMF was added, and the mixture was stirred at 60°C for 3 hours. Stirred for an hour. After cooling to room temperature, 300 parts of water was added and the precipitated solid was collected by filtration. The solid obtained above was dissolved in 180 parts of cyclopentanone, washed three times with 60 parts of dilute hydrochloric acid and once with 60 parts of aqueous sodium bicarbonate to remove unreacted raw materials, and the organic layer was concentrated under vacuum. 31 parts of compound A-3 solution (solid content: 40%) was obtained (yield: 77%).

Example 4 <Synthesis of compound (compound A-4) represented by general formula (1)>
A 500 ml round bottom flask equipped with a Teflon-coated stir bar was charged with 8.44 parts (0.040 mol) of 6-maleimidohexanoic acid (compound No. 2 above) and 20 parts of DMF. After cooling the mixture with ice, 10.15 parts (0.080 mol) of oxalyl chloride was slowly added, and the mixture was stirred at room temperature for 2 hours. Then, 4.33 parts (0.020 mol) of 3,3'-diamino-4,4'-dihydroxybiphenyl (the compound of No. 6 above) dissolved in 10 parts of DMF was added, and the mixture was stirred at 60°C for 3 hours. After cooling to room temperature, 300 parts of water was added and the precipitated solid was collected by filtration. The solid obtained above and 100 parts of methanol are placed in a flask and washed with stirring at 40° C., and then the unreacted starting material is removed by filtering the solid from which the unreacted starting material has been removed, yielding compound A-4. 9.6 parts were obtained (yield 80%).

Example 5 <Synthesis of compound (compound A-5) represented by general formula (1)>
Into a 500 ml round-bottomed flask equipped with a Teflon-coated stir bar, 9.49 parts of 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid (compound No. 4 above) (0.49 parts) are added. 040 mol), and 20 parts of DMF were added. After cooling the mixture with ice, 10.15 parts (0.080 mol) of oxalyl chloride was slowly added, and the mixture was stirred at room temperature for 2 hours. Then, 4.33 parts (0.020 mol) of 3,3'-diamino-4,4'-dihydroxybiphenyl (the compound of No. 6 above) dissolved in 10 parts of DMF was added, and the mixture was stirred at 60°C for 3 hours. After cooling to room temperature, 300 parts of water was added and the precipitated solid was collected by filtration. The solid obtained above and 100 parts of methanol were placed in a flask and stirred at 40° C., and then the solid was collected by filtration to remove unreacted raw materials to obtain 4.0 parts of compound A-5 (collected rate 30%).

Example 6 <Synthesis of compound (compound A-6) represented by general formula (1)>
A 500 ml round bottom flask equipped with a Teflon-coated stir bar was charged with 19.3905 g (0.0918 mol) of 6-maleimidohexanoic acid (compound No. 2 above), 44.6085 g of NMP. After the mixture was ice-cooled, 12.5655 g (0.1056 mol) of thionyl chloride was slowly added, and the mixture was stirred at 5°C or lower for 30 minutes. After that, 7.9046 g (0.0306 mol) of 2,2-bis(3-amino-4-hydroxyphenyl)propane (the compound of No. 7 above), 0.019 g of BHT, 10.4572 g of NMP, and 7.1202 g of picoline were dissolved. was added and stirred for 50 minutes. After 50 minutes, the entire amount of the solution was slowly added dropwise to 1000 g of water to obtain the desired solid. The solid was dissolved in 80 g of acetone, and the whole amount of the solution was slowly added dropwise to 1000 g of water for reprecipitation. The solid was dried under vacuum and collected. The amount of solid (compound A-6) obtained was 16.77 g, and the yield was 85%.

Example 7 <Synthesis of compound (compound A-7) represented by general formula (1)>
In a 500 ml round bottom flask equipped with a Teflon coated stir bar, 18.9922 g (0.0800 mol) of 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid (compound No. 4 above), 83.72 g of NMP. was put in. After the mixture was ice-cooled, 20.40 g (0.1600 mol) of thionyl chloride was slowly added, and the mixture was stirred at 5°C or lower for 30 minutes. After that, 12.2114 g (0.040 mol) of bis(3-amino-4-hydroxyphenyl)sulfone (the compound of No. 8 above), 0.019 g of BHT, 12.9168 g of NMP, and 10.13 g of picoline were dissolved and added. Stir for a minute. After 50 minutes, the entire amount of the solution was slowly added dropwise to 1000 g of water to obtain the desired solid. The solid was dissolved in 80 g of acetone, and the whole amount of the solution was slowly added dropwise to 1000 g of water for reprecipitation. The solid was dried under vacuum and collected. The amount of solid obtained (compound A-7) was 15.00 g, and the yield was 52%.

Example 8 <Synthesis of compound (compound A-8) represented by general formula (1)>
A 500 ml round bottom flask equipped with a Teflon-coated stir bar was charged with 19.3905 g (0.0918 mol) of 6-maleimidohexanoic acid (compound No. 2 above), 44.6085 g of NMP. After the mixture was ice-cooled, 12.5655 g (0.1056 mol) of thionyl chloride was slowly added, and the mixture was stirred at 5°C or lower for 30 minutes. After that, 8.5776 g (0.0306 mol) of bis(3-amino-4-hydroxyphenyl)sulfone (the compound of No. 8 above), 0.019 g of BHT, 10.4572 g of NMP, and 7.1202 g of picoline were dissolved and added. Stir for a minute. After 50 minutes, the entire amount of the solution was slowly added dropwise to 1000 g of water to obtain the desired solid. The solid was dissolved in 80 g of acetone, and the whole amount of the solution was slowly added dropwise to 1000 g of water for reprecipitation. The solid was dried under vacuum and collected. The amount of solid (compound A-8) obtained was 20.40 g, and the yield was 76%.

Example 9 (Evaluation of intramolecular (dehydration) ring-closing temperature of compounds of the present invention)
Compounds (A-1) to (A-8) obtained in Examples 1 to 8 were measured in nitrogen at a temperature increase rate of 10° C./ The intramolecular (dehydration) ring-closing temperature was measured under conditions of minutes. The intramolecular (dehydration) ring closure temperatures of compounds (A-1) to (A-8) were all less than 300°C.

Examples 10-17 (Preparation of Compositions of the Invention)
Each component was blended in the number of parts shown in Table 1 to prepare the composition of the present invention.

Comparative Example 1 (Preparation of the composition of Comparative Example 1)
Each component was blended in the number of parts shown in Table 1 to prepare a composition for comparison.
The bismaleimide compound C-1 was synthesized by a known method using the method described in US Pat. No. 5,973,166A.

The ingredients used in the compositions of Examples 10 to 17 and Comparative Example 1 listed in Table 1 are as follows.
A-1 to A-8: Bismaleimide compounds A-1 to A-8 obtained in Examples 1 to 8
C-1: Bismaleimide compound C-1
Photoinitiator 2-1: 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyloxime) (manufactured by BASF Japan, "IRGACURE OXE- 02")
Photopolymerization initiator 2-2: 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., "DETX-S")

(Preparation of polymer film and polybenzoxazole film of the present invention and cured film for comparison)
Using an applicator, the composition obtained in each of Examples 10 to 17 was applied onto a copper foil having a thickness of 18 μm, and then dried at 100 ° C. for 120 minutes to form a composition having a thickness of 20 μm on the copper foil. A layer was formed. The composition layer on the copper foil obtained above is exposed using a conveyor UV irradiation device CS30L-1-1 manufactured by GS Yuasa Co., Ltd. so that the exposure amount at a wavelength of 365 nm is 1000 mJ / cm ² , Then, the film was heated at 150° C. for 60 minutes to obtain a film in which the polymer of the present invention was cured on the copper foil. Thereafter, the polymer film was heated at 300° C. for 60 minutes to cause a ring closure reaction, thereby obtaining the polybenzoxazole film of the present invention on the copper foil. Thereafter, the copper foil was removed by etching to obtain the polybenzoxazole film of the present invention separated from the copper foil.
Also, using the composition obtained in Comparative Example 1, a comparative cured film separated from the copper foil was obtained in the same manner as described above.

(Dielectric properties of polybenzoxazole film and cured film for comparison: evaluation of dielectric constant Dk and dielectric loss tangent Df)
Each polybenzoxazole film obtained above was cut into a length of 60 mm and a width of 3 mm, and a plurality of pieces were laminated to prepare a test piece of polybenzoxazole film having a thickness of 50 to 300 μm. A test piece of the obtained polybenzoxazole film was dried in a desiccator filled with silica gel for 12 hours. Using a CP531 (10 GHz band resonator) manufactured by the same company, the permittivity Dk and the dielectric loss tangent Df were measured as dielectric properties by the cavity resonator perturbation method. The measurement conditions were a frequency of 10 GHz and a measurement temperature of 25°C. Similarly, the dielectric properties of the cured film for comparison were also measured. Table 1 shows the results.

(5% weight loss temperature evaluation of polybenzoxazole film and cured film for comparison)
The weight loss temperature of each of the polybenzoxazole films prepared according to the above "Preparation of the polybenzoxazole film of the present invention" was measured at 10°C in nitrogen using a differential thermal thermogravimeter (TG/DTA6200 manufactured by Seiko Instruments Inc.). /min to determine the 5% weight loss temperature. Similarly, the 5% weight loss temperature of the cured film for comparison was also measured. Table 1 shows the results.

(Glass transition temperature (Tg) evaluation of polybenzoxazole film and cured film for comparison)
The dynamic viscoelasticity of each of the polybenzoxazole films prepared according to the above "Preparation of the polybenzoxazole film of the present invention" was measured using a dynamic viscoelasticity measurement device (DMA) (RSA-G2 manufactured by TA Instruments). ) (frequency 1 Hz, tensile mode, heating rate 3° C./min), and the glass transition temperature was obtained from the maximum value of the loss tangent (tan δ). Similarly, the glass transition temperature of the cured film for comparison was also measured. Table 1 shows the results.

(Evaluation of alkali solubility of composition)
Using a spin coater, each of the compositions obtained in Examples 10 to 17 and Comparative Example 1 was applied to a silicon substrate and then dried at 95° C. for 15 minutes to form a composition having a thickness of 10 μm on the silicon substrate. Each layer was formed. The resulting composition layer on the silicon substrate was immersed in 100 g of a 2.38% tetramethylammonium hydroxide aqueous solution (Tokuso SD-1 manufactured by Tokuyama) for 5 minutes to confirm the solubility. Solubility was evaluated according to a three-grade standard of good: ◯, moderate: Δ, and poor: ×.

The polymer having the structural unit represented by the formula (2) of the present invention is a photosensitive polybenzoxazole precursor having negative patterning ability, and an alkaline aqueous solution can be used for patterning. is. Therefore, industrial wastes of organic solvents, which have been generated in large amounts in the past, can be completely abolished. In addition, the polybenzoxazole film finally obtained has excellent heat resistance and electrical properties, so it can be used as a surface protection film for semiconductors, an interlayer insulation film, and an insulation film for rewiring layers, which are commonly used. became possible. TECHNICAL FIELD The present invention relates to a resin skeleton itself used in a photosensitive resin composition and a method for producing the same. These are based on completely new inventions, and it is easy to understand that they are unique and very excellent inventions.
Other modifications and variations will become apparent to those skilled in the art in view of the above detailed description of the invention. However, it will be apparent that such other modifications and variations may be made without departing from the spirit and scope of the invention.

Claims (11)

Formula (A) below

(In the formula, Y represents a direct bond or a divalent linking group.)
A carbon atom having a substituent represented by
A bismaleimide compound having two partial structures in one molecule in which a carbon atom having a hydroxyl group is directly bonded. Formula (1) below

(Wherein, ring a represents a benzene ring or a cyclohexane ring. X and Y each independently represent a direct bond or a divalent linking group, and multiple Y may be the same or different. Z is ring a represents a monovalent substituent attached to , and when there is more than one Z, each Z may be the same or different, L and M are the number of substituents Z, and each independently represents a number of 0 to 3 represents an integer.)
The bismaleimide compound according to claim 1, represented by: 3. The bismaleimide compound according to claim 2, wherein X is a direct bond or a divalent linking group containing one or more selected from the group consisting of carbon atoms, fluorine atoms, sulfur atoms and oxygen atoms. X is a direct bond, or the following formulas (a) to (f)

The bismaleimide compound according to claim 3, which is a divalent linking group represented by any one of 5. The bismaleimide compound according to any one of claims 1 to 4, wherein Y is an alkylene group having 1 to 11 carbon atoms or an alkylene group having 1 to 11 carbon atoms including a divalent aromatic group. A composition comprising the bismaleimide compound according to any one of claims 1 to 5 and a compound capable of reacting with a maleimide group. A composition comprising the bismaleimide compound according to any one of claims 1 to 5, and a photopolymerization initiator or a curing catalyst. Formula (2) below

(Wherein, X, Y, Z, L, M and ring a have the same meanings as X, Y, Z, L, M and ring a in formula (1) described in claim 1.)
A polymer having 2 to 150 structural units represented by the self-polymerization product of the bismaleimide compound according to any one of claims 2 to 5 or the copolymerization of the composition according to claim 6 A polymer that is a substance. Formula (3) below

(Wherein, X, Y, Z, L, M and ring a have the same meanings as X, Y, Z, L, M and ring a in formula (1) described in claim 1.)
9. A polybenzoxazole which is an intramolecularly dehydrated cyclic product of the polymer according to claim 8, which is a polybenzoxazole having 2 to 150 structural units represented by the following. A semiconductor device comprising a surface protective film, an interlayer insulating film, or an insulating film of a rewiring layer containing the polybenzoxazole according to claim 9 . A dry film resist obtained by sandwiching a composition containing the bismaleimide compound according to any one of claims 1 to 5 and a photopolymerization initiator between substrates.