JP2008280261A - Polyimide having hydroxyamide group, precursor thereof, photosensitive resin composition using them, and cured product thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyimide having a hydroxyamide group, and high transmissivity of h-ray (405 nm) or g-ray (435 nm), a precursor thereof, a positive-type photosensitive resin composition containing a diazonaphthoquinone-based photosensitizer, and a polybenzoxazole-imide obtained through an alkali development, washing and thermal dehydration cyclization reaction steps after pattern exposure thereof, and useful as a protective membrane of a semiconductor element. <P>SOLUTION: The polyimide precursor containing the hydroxyamide group is obtained, for example, by reacting a hydroxyamide group-containing tetracarboxylic dianhydride represented by formula (1) with a diamine. The polybenzoxazole-imide is obtained by using the polyimide precursor containing the hydroxyamide group as a raw material, and subjecting the compound to heat treatment. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a positive photosensitive resin composition comprising a hydroxyamide group-containing polyimide film having high h-line (405 nm) or g-line (435 nm) transmittance or a precursor film containing a diazonaphthoquinone photosensitizer, Further, the present invention relates to a polybenzoxazole imide film useful as a protective film for a semiconductor element and a fine pattern thereof obtained through an alkali development / washing / heat dehydration cyclization reaction process after pattern exposure.

  In recent years, the importance of polyimide as a heat-resistant insulating material in electronic devices has been increasing. Polyimide has not only excellent heat resistance, but also chemical resistance, radiation resistance, electrical insulation, and excellent mechanical properties, so it can be used for flexible printed circuit (FPC) substrates, tape automation bonding (TAB). ) Base materials, chip-on-film (COF) base materials, protective films for semiconductor elements, interlayer insulating films for integrated circuits, and the like.

The polyimide film is obtained by polymerizing a solvent-soluble precursor (polyamic acid) by subjecting diamine and tetracarboxylic dianhydride to an equimolar polyaddition reaction in a solvent such as N-methyl-2-pyrrolidone without catalyst. The varnish can be easily produced by solution cast film formation, drying, and heat dehydration cyclization (imidation reaction).
In this way, the polyimide film is suitable for semiconductor applications that hate residual halogens, metal ions, and the like that may cause a decrease in electrical characteristics because the film purity is extremely high in addition to its simple manufacturing process. Further, it is advantageous in that it is easy to improve the physical properties using various available monomers and easily cope with the increasingly demanded characteristics in recent years.

  Moreover, as a protective coating material on the surface of the semiconductor chip, the chip is protected from curing shrinkage of the sealing material such as epoxy resin, the chip is protected from the thermal shock and the rapid thermal expansion stress of the sealing material in the solder reflow process, the chip When an inorganic passivation film is formed on top, preventing cracks, preventing soft errors due to α-ray shielding from trace amounts of uranium and thorium contained in the inorganic filler in the sealing material, interlayer insulation of multilayer wiring circuits, and flattening Heat resistant polyimide is currently used for the purpose of preventing disconnection of wiring.

  The protective coating material is subjected to fine processing such as via hole formation by plasma etching or alkali etching on the bonding pad portion. A dry method such as plasma etching is generally excellent in resolution, but is expensive in terms of equipment, so that wet etching using an alkaline aqueous solution or the like is simpler.

  Conventionally, microfabrication of a polyimide film was performed by forming a photoresist layer on the polyimide film and etching the exposed portion with hydrazine or strong alkali, but imparted photosensitive performance to the polyimide or its precursor itself. By using photosensitive polyimide, the microfabrication process of polyimide can be greatly shortened, and the semiconductor manufacturing speed and yield can be dramatically increased.

  For this purpose, a positive photosensitive polyimide capable of alkali development in which a diazonaphthoquinone photosensitizer is dispersed in a polyamic acid film as a polyimide precursor has been studied. However, since the carboxyl group in the polyamic acid has a low pKa value of 4 to 5, the alkali solubility of the polyamic acid is originally inherent in the aqueous solution of tetraammonium hydroxide (TMAH) that is usually used as a developing solution in the semiconductor manufacturing process. A problem has been pointed out that it is difficult to obtain a sufficient solubility difference between the exposed portion and the unexposed portion because it is too high, and is not suitable for high-resolution fine processing.

  In recent years, a phenolic hydroxy group-containing polybenzoxazole precursor having an appropriate pKa value (about 10) instead of a polyimide precursor unsuitable for alkali development as described above from the viewpoint of high resolution and precise pattern shape control A positive photosensitive polybenzoxazole system that combines this with a diazonaphthoquinone photosensitizer (hereinafter referred to as DNQ) has attracted attention.

  Polybenzoxazole (hereinafter referred to as PBO) obtained by thermal ring-closing reaction of polyhydroxyamide (hereinafter referred to as PHA), which is a polybenzoxazole precursor, has heat resistance equivalent to that of polyimide, and is superior to polyimide. It is an excellent material as a semiconductor protective coating material in that it has water absorption.

  However, the process for producing PHA, which is a PBO precursor, is not as simple as the polyamic acid system, which is a polyimide precursor. In the case of polyamic acid, a high polymer can be obtained very easily without catalyst and at room temperature by an equimolar polyaddition reaction of tetracarboxylic dianhydride and diamine in an amide solvent such as N-methyl-2-pyrrolidone (NMP). On the other hand, in the PHA system, the dicarboxylic acid is first converted to an active acyl, which is polycondensed with bis (o-aminophenol) under heating conditions, and further requires a PHA isolation / generation step, so that the polymerization step is further performed. It is complicated.

  In addition, bis (o-aminophenol) is commercially available in nature as 3,3′-dihydroxybenzidine (HAB) or 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (BAHF). In contrast to polyimide systems with a wide monomer selection range, it is difficult to meet the increasingly demanding characteristics of semiconductor materials.

  In many cases, PHA as a PBO precursor has lower solubility in a solvent than polyamic acid as a polyimide precursor. This is because the polyamic acid has a carboxyl group which is advantageous for solvation in the side chain, and the amide bond of the main chain generated in the polymerization process becomes a para / metarandom chain and is easily soluble in the solvent. This is because in the PHA system, the side chain is a hydroxy group which is disadvantageous for solvation, and the amide bond is not a random chain.

  As described above, there are advantages and disadvantages between the photosensitive polyimide system and the photosensitive PBO system. However, if the polymerization process is an advantage of the polyimide system and the physical property is easily improved (various available monomers), the PBO If there is a heat-resistant material that has both high resolution processing ease, which is an advantage of the system, it can provide a very useful material in the industrial field, but such a photosensitive heat-resistant material is hardly known. Currently.

（式（８）中、Ｘは４価の芳香族基を表す。） For example, it is known that a clear positive pattern can be formed by using a photosensitive resin composition in which a phenolic hydroxy group-containing polyimide represented by the following formula (8) and DNQ are combined (for example, non-patent) Reference 1 and Patent Reference 1).

(In formula (8), X represents a tetravalent aromatic group.)

  The phenolic OH group-containing polyimide represented by formula (8) uses bis (o-aminophenol) as a diamine component, and equimolar polyaddition reaction with tetracarboxylic dianhydride to first polymerize the OH group-containing polyamic acid. After that, it is produced by a thermal imidization reaction. However, unlike a normal PBO precursor, this phenolic OH group-containing polyimide does not disappear but remains phenolic OH groups even if it is heat-treated after forming a positive pattern by alkali development. For this reason, in applications that are used for a long time as a permanent protective film of an integrated circuit, such as a semiconductor application such as a buffer coat film, the presence of a phenolic OH group is a trigger, which causes problems such as ion migration and increased water absorption. In addition, various unexpected problems may occur.

（式（１０）中、Ｒは２価の芳香族基を表す。） Also disclosed is a technique for polymerizing a polyimide precursor represented by the following formula (10) using a tetracarboxylic dianhydride represented by the following formula (9) and using this to form a positive pattern. (For example, refer to Patent Document 2).

(In formula (10), R represents a divalent aromatic group.)

  However, the tetracarboxylic dianhydride represented by the formula (9) is likely to be colored due to partial oxidation of the phenolic OH group, and the polyimide precursor and the polyimide cast film obtained using this are often markedly colored. , Leading to undesirable results such as reduced g-ray transmission (ie reduced sensitivity).

  In addition, the glass transition temperature after thermosetting is preferably 300 ° C. or higher for the buffer coat film application of the semiconductor integrated circuit, but in the film obtained by heat curing the polyimide precursor represented by the formula (10), Since it has a trifluoromethyl group that acts to weaken the intermolecular force, a sufficiently high glass transition temperature may not be obtained.

  If the bis (o-aminophenol) other than BAHF can be used to suppress the coloring of the photosensitive film, and the glass transition temperature of the film after heat curing is 300 ° C. or higher, the phenolic OH group-containing polyimide precursor If a body or a polyimide system is obtained, a material useful for the industrial field can be provided, but such a material is not known.

Journal of Applied Polymer Science, 53, 1513-1524 (1994) WO01 / 034679 Japanese Patent Laid-Open No. 11-100503

The present invention relates to a positive photosensitive resin composition comprising a hydroxyamide group-containing polyimide having a high transmittance at h-line (405 nm) or g-line (435 nm) or a precursor thereof and a diazonaphthoquinone photosensitizer, and After the pattern exposure, polybenzoxazole imide useful as a protective film for a semiconductor element obtained through an alkali development / washing / heat dehydration cyclization reaction step is provided.

As a result of intensive research in view of the above problems, a hydroxyamide group-containing polyimide precursor represented by the following formula (3) or a hydroxyamide group-containing polyimide represented by the following formula (6) and a diazonaphthoquinone photosensitizer The polybenzoxazole imide represented by the following formula (7) obtained by heat-curing the composition further has a high glass transition temperature of 300 ° C. or higher. As a result, it has been found that the material is useful as a protective film for an integrated circuit of a semiconductor element, and the present invention has been completed.

２．下式(２)で表されるヒドロキシアミド基含有テトラカルボン酸二無水物。

３．下式（３）：

で表される反復単位を含有するヒドロキシアミド基含有ポリイミド前駆体。（式（３）中、Ａは下式（４）または（５）で表され、Ｂは２価の芳香族基または脂肪族基を表す。）

４．固有粘度が０．４ｄＬ／ｇ以上である、要旨３に記載のヒドロキシアミド基含有ポリイミド前駆体。

５．下式（６）：

で表される反復単位を含有するヒドロキシアミド基含有ポリイミド。（式（６）中、AおよびBは式（３）におけるのと同じ意味を表す。）

６．固有粘度が０．４ｄＬ／ｇ以上である、要旨５に記載のヒドロキシアミド基含有ポリイミド。

７．４３５ｎｍ（ｇ線）および４０５ｎｍ（ｈ線）におけるキャストフィルム（膜厚１０μｍ）の光透過率がそれぞれ５０％以上および１０％以上である請求項５または６に記載のヒドロキシアミド基含有ポリイミド。

８．下式（７）：

で表される反復単位を含有するポリベンゾオキサゾールイミド。（式（７）中、ＡおよびＢは式（３）におけるのと同じ意味を表す。）

９．３００℃以上のガラス転移温度を有することを特徴とする、要旨８に記載のポリベンゾオキサゾールイミド。

１０．要旨３または４に記載のヒドロキシアミド基含有ポリイミド前駆体を加熱あるいは脱水環化試薬を用いてイミド化反応させることを特徴とする要旨５〜７のいずれかに記載のヒドロキシアミド基含有ポリイミドの製造方法。

１１．要旨３または４に記載のヒドロキシアミド基含有ポリイミド前駆体あるいは、要旨５〜７のいずれかに１項に記載のヒドロキシアミド基含有ポリイミドを加熱あるいは脱水環化試薬を用いて脱水閉環反応することを特徴とする要旨８または９に記載のポリベンゾオキサゾールイミドの製造方法。

１２．要旨３または４のいずれかに記載のヒドロキシアミド基含有ポリイミド前駆体あるいは、要旨５〜７のいずれか１項に記載のヒドロキシアミド基含有ポリイミドおよびジアゾナフトキノン系感光剤を含有して成るポジ型感光性樹脂組成物。

１３．要旨１２に記載の感光性樹脂組成物からなる膜をパターン露光およびアルカリ現像後、加熱あるいは脱水環化試薬で処理して得られることを特徴とするポリベンゾオキサゾールイミドの微細パターン。

１４．要旨８または９に記載のポリベンゾオキサゾールイミドを含有してなる半導体素子の保護膜。 That is, the gist of the present invention is as follows.
1. A hydroxyamide group-containing tetracarboxylic dianhydride represented by the following formula (1):

2. A hydroxyamide group-containing tetracarboxylic dianhydride represented by the following formula (2):

3. The following formula (3):

A hydroxyamide group-containing polyimide precursor containing a repeating unit represented by: (In formula (3), A is represented by the following formula (4) or (5), and B represents a divalent aromatic group or aliphatic group.)

4). 4. The hydroxyamide group-containing polyimide precursor according to summary 3, having an intrinsic viscosity of 0.4 dL / g or more.

5. The following formula (6):

A hydroxyamide group-containing polyimide containing a repeating unit represented by: (In formula (6), A and B represent the same meaning as in formula (3).)

6). The hydroxyamide group-containing polyimide according to summary 5, wherein the intrinsic viscosity is 0.4 dL / g or more.

7. The hydroxyamide group-containing polyimide according to claim 5 or 6, wherein the light transmittance of the cast film (film thickness: 10 μm) at 7.435 nm (g line) and 405 nm (h line) is 50% or more and 10% or more, respectively.

8). The following formula (7):

A polybenzoxazole imide containing a repeating unit represented by: (In Formula (7), A and B represent the same meaning as in Formula (3).)

9. The polybenzoxazole imide according to item 8, which has a glass transition temperature of 300 ° C. or higher.

10. The production of a hydroxyamide group-containing polyimide according to any one of points 5 to 7, wherein the hydroxyamide group-containing polyimide precursor according to summary 3 or 4 is heated or subjected to an imidization reaction using a dehydrating cyclization reagent. Method.

11. The hydroxyamide group-containing polyimide precursor described in Summary 3 or 4 or the hydroxyamide group-containing polyimide described in any one of Summary 5 to 7 is heated or subjected to a dehydration cyclization reaction using a dehydration cyclization reagent. 10. A method for producing a polybenzoxazole imide according to the feature 8 or 9.

12 A positive photosensitive material comprising the hydroxyamide group-containing polyimide precursor according to any one of Summary 3 or 4 or the hydroxyamide group-containing polyimide according to any one of Summary 5 to 7 and a diazonaphthoquinone photosensitizer. Resin composition.

13. A fine pattern of polybenzoxazole imide obtained by subjecting a film comprising the photosensitive resin composition described in the summary 12 to pattern exposure and alkali development, and then treating with a heating or dehydrating cyclization reagent.

14 A protective film for a semiconductor element, comprising the polybenzoxazole imide according to item 8 or 9.

The hydroxyamide group-containing tetracarboxylic dianhydride of the present invention exhibits high polymerization reactivity with diamine, and gives a hydroxyamide group-containing polyimide precursor and polyimide having a high degree of polymerization. The photosensitive resin composition of the present invention containing these resins and a diazonaphthoquinone photosensitizer makes it possible to form a high-resolution positive pattern, and polybenzoxazole imide obtained by heat curing (dehydration cyclization reaction). Has a high glass transition temperature of 300 ° C. or higher, and is extremely useful as a buffer coat film for integrated circuits.

<Molecular design>
First, the tetracarboxylic dianhydride monomer used for producing the hydroxyamide group-containing polyimide and the precursor thereof of the present invention will be described. According to the present invention, a photosensitive material satisfying the above required characteristics can be obtained by using a hydroxyamide group-containing tetracarboxylic dianhydride represented by the following formula (1) or (2).

  The tetracarboxylic dianhydride is obtained by using bis (3-amino-4-hydroxyphenyl) sulfone (hereinafter referred to as ABPS) or 3, instead of using conventional BAHF as the raw material bis (o-aminophenol). It is synthesized by reacting with trimellitic anhydride using 3′-diamino-4,4′-dihydroxydiphenyl ether (hereinafter referred to as ADPE). The hydroxyamide group-containing tetracarboxylic dianhydride according to the present invention uses these bis (o-aminophenols) to produce a tetracarboxylic dianhydride that is less colored than when BAHF is used. Can do. Due to the little coloring, the hydroxyamide group-containing polyimide of the present invention and its precursor film obtained by using this are the emission lines of high-pressure mercury, ie g-line (435 nm) and h-line (405 nm), which are commonly used irradiation light sources. Or it has a high transmittance in i-line (365 nm). When the transmittance is low, the irradiated ultraviolet rays are not efficiently absorbed by the photosensitive agent dispersed in the film, and there is a possibility that the ultraviolet irradiation time necessary for pattern formation is significantly increased (decrease in sensitivity).

  A feature of the present invention is that the hydroxyamide group-containing polyimide precursor is heat-treated in a solution under mild conditions, so that only the thermal imidization is performed without affecting the hydroxyamide group (without cyclization). An amide group-containing polyimide can be produced, and the hydroxyamide group can be completely converted into a benzoxazole ring by heat treatment at a higher temperature after forming a positive pattern. In this way, the phenolic OH group can be completely eliminated in the end, so that when it is applied as a protective film of a semiconductor element, unexpected serious problems caused by ion migration and water absorption are caused. It can be avoided.

  When the photosensitive resin composition film is prepared by combining the hydroxyamide group-containing polyimide of the present invention and DNQ by a solution casting method, the hydroxyamide group-containing polyimide is highly soluble in a solvent such as DMAc and NMP and stable in varnish. It is necessary to have a property (do not cause gelation or the like). Generally, polyimide has poor solvent solubility due to strong intermolecular forces between imide groups, but the polyimide of the present invention has high solvent solubility due to the presence of sulfonyl or ether groups in the bis (o-aminophenol) used. Holds sex. In particular, the presence of a sulfonyl group in ABPS contributes to an improvement in the glass transition temperature of polybenzoxazole imide obtained after heat curing in addition to an improvement in solvent solubility. The ether group in ADPE is extremely effective for improving the toughness of the film.

<Method for producing hydroxyamide group-containing tetracarboxylic dianhydride>
The manufacturing method of this hydroxyamide group containing tetracarboxylic dianhydride is not specifically limited, A well-known method is applicable. Specifically, an amidation reaction is performed using the raw material ABPS or ADPE and a trimellitic anhydride derivative.
The case where ABPS is used will be described below.
As a method applicable at this time, a method of directly dehydrating the amino group of ABPS and the carboxyl group of trimellitic anhydride at a high temperature or amidating using a condensing agent such as triphenyl phosphite / pyridine or dicyclohexylcarbodiimide, Examples include a method (acid halide method) in which the carboxyl group of trimellitic anhydride is converted to an acid halide, and this is reacted with ABPS in the presence of a deoxidizer (base). Among the above-mentioned methods, the acid halide method can be preferably applied in terms of economy and reactivity.

  When the acid halide method is applied, trimellitic anhydride chloride is preferably used. When this and ABPS are reacted, a silylating agent can also be used in order to increase the selectivity of the reaction. That is, in order to avoid a reaction (esterification reaction) with a hydroxyl group in ABPS, both the amino group and the hydroxyl group in ABPS are silylated with a silylating agent, whereby the silylated hydroxyl group loses its reactivity. The amidation reaction can be selectively performed. Usually, the amidation reaction can be substantially selectively carried out by carrying out the reaction at a low temperature such as −20 to 0 ° C.

  Next, a method for synthesizing the hydroxyamide group-containing tetracarboxylic dianhydride by the acid halide method will be specifically described, but the synthesis method is not particularly limited to the following description. First, trimellitic anhydride chloride (Amol) is dissolved in a solvent and sealed with a septum cap. This solution is slowly dropped with a syringe or a dropping funnel into ABPS (0.5 × Amol) and an appropriate amount of a deoxidizing agent dissolved in the same solvent. After the addition is complete, the reaction mixture is stirred for 3 hours. If the target compound is highly soluble in the solvent used in the synthesis, first the hydrochloride formed is filtered from the reaction mixture, the filtrate is evaporated using an evaporator, and dried in a vacuum at 20-100 ° C. for 24 hours to form a powder. To obtain a crude product. If the solubility of the target product is low, the target product is filtered off. When pyridine is used as the deoxidizer, it precipitates as a mixture with pyridine hydrochloride, and is washed with a large amount of water to dissolve and remove only the hydrochloride. Next, the crude product partially hydrolyzed in the partial washing step is vacuum-dried at 20 to 100 ° C. The hydroxyamide group-containing tetracarboxylic dianhydride having a high purity can be obtained by subjecting the crude product thus obtained to polymerization through an appropriate solvent through recrystallization, washing, and vacuum drying.

  The solvent that can be used in this reaction is not particularly limited as long as it is inert to trimellitic anhydride chloride and ABPS as raw materials and dissolves the target compound, but acetone, tetrahydrofuran, 1, 4-dioxane, picoline, pyridine, chloroform, toluene, xylene, dichloromethane, chloroform, 1,2-dichloroethane, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-diethylacetamide, N, N- Aprotic solvents such as dimethylformamide, hexamethylphosphoramide, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, 1,2-dimethoxyethane-bis (2-methoxyethyl) ether, And phenol, o-cresol, m-crezo And protic solvents such as alcohol, p-cresol, o-chlorophenol, m-chlorophenol, and p-chlorophenol. These solvents may be used alone or in combination of two or more. Acetone, tetrahydrofuran and 1,4-dioxane are preferably used from the viewpoint of solubility of the reaction reagent and easiness of distillation.

  The amidation reaction is performed at -20 to 30 ° C, but it is desirable to perform the reaction while cooling at -20 to 0 ° C from the viewpoint of suppressing by-products. If the reaction temperature is higher than 50 ° C., some side reactions occur, which may reduce the yield, which is not preferable.

  The reaction for obtaining the hydroxyamide group-containing tetracarboxylic dianhydride is carried out in a solute concentration range of 5 to 50% by weight. In consideration of solubility of raw materials, side reaction control, and filtration step of precipitation, it is preferably carried out in the range of 10 to 40% by weight.

  Although it does not specifically limit as a deoxidizer used for reaction, Inorganic bases, such as epoxy compounds, such as a propylene oxide, organic tertiary amines, such as a pyridine, a triethylamine, N, N- dimethylaniline, potassium carbonate, and sodium hydroxide. Used. Propylene oxide is preferably used from the viewpoint that the reaction does not produce hydrochloride and simplifies the isolation process.

The precipitate produced by the reaction contains water-soluble pyridine hydrochloride when pyridine is used as a deoxidizing agent. In this case, for example, when tetrahydrofuran is used as the solvent, pyridine hydrochloride is hardly dissolved in the solvent, so that the hydrochloride can be separated almost completely only by filtering the reaction solution. Usually, when the solubility of the target product is high, the target product is dissolved in the filtrate. Therefore, the target product with sufficiently high purity and high yield can be obtained simply by distilling off the solvent from the filtrate and recrystallizing from a suitable solvent. Is obtained.
For example, when ABPS is used as described above, the hydroxyamide group-containing tetracarboxylic dianhydride of the present invention is obtained. Tetracarboxylic dianhydride is obtained.

  Generally used tetracarboxylic dianhydride is treated with an organic acid anhydride such as acetic anhydride before heating for polymerization, or heated and dried under vacuum to absorb moisture in the air and slightly hydrolyze it. A pretreatment is often performed to completely dehydrate the ring portion. However, in the case of the hydroxyamide group-containing tetracarboxylic dianhydride of the present invention, care must be taken when it is treated with acetic anhydride because the hydroxyl group may be acetylated depending on the reaction conditions. Further, when heated at a high temperature, there is a risk that undesirable side reactions such as an intermolecular esterification reaction between a hydroxyl group and an acid anhydride group may occur in addition to a cyclization reaction of a hydroxyamide group to a benzoxazole ring. It should not be heat treated above ℃.

<Method for producing hydroxyamide group-containing polyimide precursor>
The method for producing the hydroxyamide group-containing polyimide precursor of the present invention is not particularly limited, and a known method can be applied. Specifically, it is manufactured by the following method. First, a diamine composed of one component or another component is dissolved in a dehydrated polymerization solvent, and a tetracarboxylic dianhydride component containing a hydroxyamide group-containing tetracarboxylic dianhydride according to the present invention is gradually added as powder to this, Stir using a mechanical stirrer. At this time, the total amount of tetracarboxylic dianhydride and the total amount of diamine are charged in substantially equimolar amounts. When two or more kinds of tetracarboxylic dianhydride powders are added, the acid dianhydride powders may be added to the solution after being mixed in advance or sequentially.

  Hereinafter, preferred specific examples of the method for producing the hydroxyamide group-containing polyimide precursor of the present invention will be described. First, a diamine is dissolved in a polymerization solvent, and then a tetracarboxylic dianhydride component powder containing the hydroxyamide group-containing tetracarboxylic dianhydride is gradually added thereto. Using a mechanical stirrer, 0-100 ° C., preferably Stir at 5-60 ° C. for 0.5-100 hours, preferably 1-50 hours. In this case, the total monomer concentration is 1 to 50% by weight, preferably 5 to 30% by weight. By carrying out polymerization in this monomer concentration range, a uniform and high degree of polymerization can be obtained.

  From the viewpoints of film formation of the hydroxyamide group-containing polyimide precursor and hydroxyamide group-containing polyimide, adhesion to the substrate, and film toughness of polybenzoxazolimide, which is a thermoset (cyclized) product thereof, the hydroxyamide group The degree of polymerization of the contained polyimide precursor is desirably as high as possible, but if the intrinsic viscosity value qualitatively indicating the molecular weight is 0.4 dL / g or more, there is no problem in film forming property, adhesiveness, and film toughness. . If the intrinsic viscosity value is lower than this value, the film-forming property and film toughness are drastically lowered, which may cause a serious problem that cannot be applied to the industrial field. When the polymerization is performed at a concentration lower than the above monomer concentration range, the degree of polymerization of the hydroxyamide group-containing polyimide precursor is not sufficiently high, and the hydroxyamide group-containing polyimide and the polybenzoxazole imide film may become brittle. Absent. On the other hand, if the polymerization is carried out at a concentration higher than this range, the monomer and the polymer to be produced are not sufficiently dissolved, and the polymerization may not proceed uniformly.

  In all tetracarboxylic dianhydrides used for polymerization in the present invention, the content of the hydroxyamide group-containing tetracarboxylic dianhydride of the present invention is in the range of 5 to 100 mol% from the viewpoint of positive pattern formation, More preferably, it is 30-100 mol%. More preferably, it is the range of 50-100 mol%. If it is 5 mol% or less, the dissolution rate in the TMAH aqueous solution may be significantly reduced, or the difference in solubility between the exposed and unexposed areas may become uncontrollable, and it may be difficult to form a clear fine pattern. It is not preferable.

  The hydroxyamide group-containing tetracarboxylic acid is within the range that does not impair the reactivity when polymerizing the hydroxyamide group-containing polyimide precursor, the solvent solubility of the hydroxyamide group-containing polyimide, the film forming property, and the required characteristics of the polybenzoxazole imide film. As tetracarboxylic dianhydride that can be partially used other than acid dianhydride, it is not particularly limited, but pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl ether tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfonetetra Carboxylic dianhydride, 2,2′-bis (3,4-dicarboxyphenyl) hexafluoropropanoic dianhydride, 2,2′-bis (3, -Dicarboxyphenyl) propanoic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, hydroquinone-bis (trimellitate) Anhydride), cyclobutanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, and the like. These may be used alone or in combination of two or more as copolymerization components.

Examples of the diamine for preparing the hydroxyamide group-containing polyimide precursor of the present invention include aromatic diamine and aliphatic diamine.
Aromatics that can be used within a range that does not impair the reactivity when polymerizing the hydroxyamide group-containing polyimide precursor of the present invention, the solvent solubility of the hydroxyamide group-containing polyimide, the film-forming property, and the required characteristics of the polybenzoxazole imide film Although it does not specifically limit as diamine, For example, p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,4-diaminoxylene, 2,4-diaminodurene, 4, 4'-diaminodiphenylmethane, 4,4'-methylenebis (2-methylaniline), 4,4'-methylenebis (2-ethylaniline), 4,4'-methylenebis (2,6-dimethylaniline), 4,4 '-Methylenebis (2,6-diethylaniline), 4,4'-diaminodiphenyl ether, 3,4'- Diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 2,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, 4,4′-diaminobenzophenone, 3,3′- Diaminobenzophenone, 4,4'-diaminobenzanilide, benzidine, 3,3'-dihydroxybenzidine, 3,3'-dimethoxybenzidine, o-tolidine, m-tolidine, 2,2'-bis (trifluoromethyl) benzidine 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 4,4′-bis (4-amino) Phenoxy) biphenyl, bis (4- (3-aminophenoxy) phenyl) sulfone, bis ( -(4-aminophenoxy) phenyl) sulfone, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, 2 , 2-bis (4-aminophenyl) hexafluoropropane, p-terphenylenediamine and the like. Two or more of these may be used in combination.

  Aliphatics that can be used as long as they do not impair the reactivity when polymerizing the hydroxyamide group-containing polyimide precursor of the present invention, the solvent solubility of the hydroxyamide group-containing polyimide, the film formability, and the required properties of the polybenzoxazole imide film Although it does not specifically limit as diamine, For example, 4,4'- methylenebis (cyclohexylamine), isophoronediamine, trans-1,4-diaminocyclohexane, cis-1,4-diaminocyclohexane, 1,4-cyclohexanebis (methyl) Amine), 2,5-bis (aminomethyl) bicyclo [2.2.1] heptane, 2,6-bis (aminomethyl) bicyclo [2.2.1] heptane, 3,8-bis (aminomethyl) Tricyclo [5.2.1.0] decane, 1,3-diaminoadamantane, 2,2-bis (4- Minocyclohexyl) propane, 2,2-bis (4-aminocyclohexyl) hexafluoropropane, 1,3-propanediamine, 1,4-tetramethylenediamine, 1,5-pentamethylenediamine, 1,6-hexamethylenediamine 1,7-heptamethylenediamine, 1,8-octamethylenediamine, 1,9-nonamethylenediamine and the like. Two or more of these may be used in combination.

  The polymerization solvent that can be used is not particularly limited, but amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ -Cyclic ester solvents such as caprolactone, ε-caprolactone, α-methyl-γ-ptyrolactone, carbonate solvents such as ethylene carbonate and propylene carbonate, glycol solvents such as triethylene glycol, m-cresol, P-cresol, 3-chloro Phenol solvents such as phenol and 4-chlorophenol, acetophenone, 1,3-dimethyl-2-imidazolidinone, sulfolane, dimethyl sulfoxide and the like are preferably employed. In addition, other common organic solvents such as phenol, o-cresol, butyl acetate, ethyl acetate, isoptyl acetate, propylene glycol methyl acetate, ethyl cellosolve, butyl cellosolve, 2-methyl cellosolve acetate, ethyl cellosolve acetate, petit Lucerosorb acetate, tetrahydrofuran, dimethoxyethane, diethoxyethane, diptyl ether, diethylene glycol dimethyl ether, methylisobutyl ketone, diisoptyl ketone, cyclohexanone, methyl ethyl ketone, acetone, butanol, ethanol, xylene, toluene, chlorobenzene, terpene Mineral spirits, petroleum naphtha solvents and the like can also be added to the solvent.

  The hydroxyamide group-containing polyimide precursor of the present invention is obtained by adding or dissolving a photosensitizer or the like in a cast film and a varnish obtained by coating or drying a polymerization solution (varnish) as it is or appropriately on a substrate. In addition to the usage form as a photosensitive resin composition film obtained by casting, the varnish is appropriately diluted and then dropped, filtered and dried in a large amount of poor solvent such as water or methanol, and isolated as a powder. You can also

  In the photosensitive resin composition containing the hydroxyamide group-containing polyimide precursor of the present invention, in addition to the photosensitive agent, an oxidation stabilizer, filler, silane coupling agent, adhesion promoter, wet heat stabilizer, light as required. Additives such as a polymerization initiator, a sensitizer, an end-capping agent, a crosslinking agent, and a flame retardant can be added.

<Method for producing hydroxyamide group-containing polyimide>
The hydroxyamide group-containing polyimide of the present invention can be produced by performing only the imidation reaction of the hydroxyamide group-containing polyimide precursor obtained by the above method without affecting the hydroxyamide group (while leaving it). . This is because the temperature range required for the thermal cyclization reaction of the hydroxyamide group to the benzoxazole ring is sufficiently higher (100 ° C. or higher) than the imidization reaction.

  The form of use of the hydroxyamide group-containing polyimide of the present invention includes a photosensitive resin composition film containing a solution (varnish), a cast film, a photosensitizer, etc., and a poor amount of water, methanol, etc. after appropriately diluting the varnish. It is a powder obtained by dropping, filtering and drying in a solvent.

  First, a method for producing a hydroxyamide group-containing polyimide varnish and powder will be described. The hydroxyamide group-containing polyimide varnish of the present invention is obtained by heating or refluxing the varnish of the hydroxyamide group-containing polyimide precursor obtained by the polymerization reaction as it is or appropriately with a solvent, and then heating and refluxing in a nitrogen atmosphere. Can be easily obtained. The reflux temperature at this time is 120 to 220 ° C., and the reflux time is 10 minutes to 12 hours, more preferably 150 to 190 ° C. for 1 to 5 hours. At this time, if the reflux temperature is lower than 120 ° C., it takes a very long time to complete imidization, so it is not adopted in terms of productivity. On the other hand, if it exceeds 220 ° C., not only imidation but also the remaining hydroxyamide group starts to cyclize, and the product is more likely to be colored, which is not preferable. It is also possible to control the reflux temperature and time to appropriately cyclize the hydroxyamide group and control the content of the phenolic OH group. To azeotropically distill off water, which is a by-product of the imidization reaction, toluene, xylene or the like may be added. Further, a base such as γ-picoline can be added as a catalyst.

  Since the hydroxyamide group-containing polyimide of the present invention has extremely high solubility in various polymerization solvents usually used for polyimide precursor polymerization, a uniform varnish is obtained without precipitation after the thermal imidization reaction. It is done.

  From the viewpoint of film formability of the hydroxyamide group-containing polyimide, adhesion to the substrate, and film toughness of polybenzoxazolimide, which is a thermoset (cyclized) product thereof, the degree of polymerization of the hydroxyamide group-containing polyimide is as high as possible. However, if the intrinsic viscosity value is 0.4 dL / g or more, there is no problem in film forming property, adhesiveness, and film toughness. If the intrinsic viscosity value is lower than this value, the film-forming property and film toughness are drastically lowered, which may cause a serious problem that cannot be applied to the industrial field.

  After imidization in the solution, the varnish obtained as described above is dropped, filtered and dried in a large amount of poor solvent such as water or methanol for the purpose of removing additives, by-products and solvents. The hydroxyamide group-containing polyimide can also be isolated as a powder. Moreover, this powder can be redissolved in the above-mentioned various solvents to form a varnish again.

  In addition, the imidization reaction is carried out by adding a tertiary amine catalyst such as pyridine or triethylamine and an organic acid dehydration cyclization reagent such as acetic anhydride into the hydroxyamide group-containing polyimide precursor varnish instead of being performed thermally. It is also possible to carry out by stirring at 100 ° C. for 10 minutes to 24 hours. At this time, the imidation rate can also be controlled by adjusting the reaction conditions such as the amount of the chemical imidizing reagent added. However, since the hydroxyl group in the hydroxyamide group-containing polyimide precursor reacts with acetic anhydride to be acetylated depending on the reaction conditions, thermal imidization is preferably used rather than chemical imidization when it is desired to avoid acetylation. However, when the purpose is to partially or completely acetylate the hydroxyl group, the acetylation rate can be controlled by adjusting the reaction conditions such as the addition amount of the chemical imidizing reagent.

  The hydroxyamide group-containing polyimide of the present invention is obtained by reacting an acid dianhydride component containing a hydroxyamide group-containing tetracarboxylic dianhydride and a diamine component at a high temperature in a solvent (one-pot polymerization), thereby producing a hydroxyamide group-containing polyimide precursor. Polymerization can be performed in one step without isolating the body. The polymerization reaction temperature is 120 to 220 ° C., the reflux time is 10 minutes to 12 hours, and more preferably 150 to 190 ° C. for 1 to 5 hours. At this time, if the polymerization temperature is lower than 120 ° C., it takes a very long time to complete the polymerization, and thus it is not adopted in terms of productivity. On the other hand, if it exceeds 220 ° C., not only polymerization but also the hydroxyamide group to be left begins to cyclize, and the product is more likely to be colored, which is not preferable. It is also possible to control the polymerization temperature and time to appropriately cyclize the hydroxyamide group and control the content of the phenolic OH group. To azeotropically distill off water, which is a by-product during the polymerization reaction, toluene, xylene or the like may be added. A base such as γ-picoline can also be added as a catalyst.

  Solvents that can be used for one-pot polymerization are not particularly limited, but aprotic solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide are preferred examples. However, phenol solvents such as m-cresol and amide solvents such as NMP can also be used. After the one-pot polymerization, the resulting varnish solution can be dropped and filtered into a large amount of poor solvent such as water or methanol to isolate the polyimide as a powder. The powder can be redissolved in various solvents to form a varnish.

  Next, the manufacturing method of a hydroxyamide group containing polyimide film is demonstrated. The hydroxyamide group-containing polyimide precursor varnish of the present invention is cast on a substrate such as an insoluble polyimide film, glass, copper, aluminum, stainless steel or silicon, and dried in an oven at 40 to 180 ° C., preferably 50 to 150 ° C. To do. The obtained hydroxyamide group-containing polyimide precursor film is heated on a substrate in a vacuum, in an inert gas such as nitrogen, or in air at 180 to 300 ° C., preferably 200 to 280 ° C. An amide group-containing polyimide film can be produced. As a heating condition, a temperature of 180 ° C. or higher is employed from the viewpoint of sufficiently carrying out the imidization ring-closing reaction, and a temperature of 300 ° C. or lower is employed from the viewpoint of suppressing cyclization of the hydroxyamide group. The imidization is preferably performed in a vacuum or in an inert gas, but may be performed in air if the imidization temperature is not too high.

  The hydroxyamide group-containing polyimide film can also be produced by casting and drying the hydroxyamide group-containing polyimide varnish on the substrate. The drying temperature is not particularly limited as long as the solvent is completely evaporated and removed, and the drying is performed at 40 to 300 ° C, preferably 100 to 280 ° C.

In the hydroxyamide group-containing polyimide film of the present invention, in addition to the photosensitive agent, if necessary, an oxidation stabilizer, a filler, a silane coupling agent, an adhesion promoter, a wet heat stabilizer, a photopolymerization initiator, a sensitizer, Additives such as end-capping agents, crosslinking agents, flame retardants and the like can be added.
The hydroxyamide group-containing polyimide film of the present invention has a light transmittance of 50% or more and 10% or more at 435 nm (g line) and 405 nm (h line) with a film thickness of 10 μm, respectively.

<Method for producing polybenzoxazole imide>
Next, the manufacturing method of the polybenzoxazole imide of this invention is demonstrated. In addition to the photosensitive resin composition film blended with varnish, cast film, photosensitizer, etc., the use form is obtained by appropriately diluting the varnish and then dropping, filtering and drying in a large amount of poor solvent such as water or methanol. Powder.

  First, a method for producing a polybenzoxazole imide film will be described. One method is a method using the hydroxyamide group-containing polyimide precursor of the present invention. That is, the hydroxyamide group-containing polyimide precursor varnish is cast on a substrate such as an insoluble polyimide film, glass, copper, aluminum, stainless steel, or silicon, and dried in an oven at 40 to 180 ° C., preferably 50 to 150 ° C. The obtained hydroxyamide group-containing polyimide precursor film is imidized by heating on a substrate in vacuum, in an inert gas such as nitrogen, or in air at 250 to 400 ° C., preferably 270 to 350 ° C. Both the benzoxazolations occur and the polybenzoxazole imide film of the present invention can be produced. This thermosetting (cyclization) step is desirably performed in vacuum or in an inert gas, but may be performed in air if the treatment temperature is not too high.

  Another method is a method using the hydroxyamide group-containing polyimide of the present invention. That is, a hydroxyamide group-containing polyimide varnish is cast on the above substrate and dried in an oven at 40 to 180 ° C., preferably 50 to 150 ° C. The obtained hydroxyamide group-containing polyimide film is heated at 250 to 400 ° C., preferably 270 to 350 ° C. in vacuum, in an inert gas such as nitrogen, or in the air on the substrate, whereby the hydroxyamide group is completely formed. To a benzoxazole ring to obtain a polybenzoxazole imide film. This thermosetting (cyclization) step is desirably performed in vacuum or in an inert gas, but may be performed in air if the treatment temperature is not too high.

  The polybenzoxazole imide can also be obtained by heating and refluxing the hydroxyamide group-containing polyimide and its precursor varnish at 180 to 250 ° C. At that time, when the polybenzoxazole imide is soluble in the solvent, it is obtained as a uniform varnish, and when it is insoluble, it is obtained as a precipitate. When a varnish of polybenzoxazole imide is obtained, a polybenzoxazole imide film can be produced by casting and drying the varnish on the substrate. The drying temperature is not particularly limited as long as the solvent is completely evaporated and removed, and the drying is performed at 40 to 400 ° C, preferably 100 to 350 ° C.

  In order to apply the polybenzoxazole imide film obtained as described above as a buffer coat film of an integrated circuit or an insulating layer of a multilayer substrate, the glass transition temperature as an index of heat resistance should be 300 ° C. or higher. desirable. If the temperature is lower than 300 ° C., there is a possibility that inconveniences such as film deformation, foaming and adhesion failure may occur in the heat process during mounting. Further, as a measure of film toughness, there is no major problem unless breakage is observed in the 180 ° bending simple test, but the break elongation in the tensile test is preferably 5% or more, more preferably 10% or more. preferable.

  In the film made of the polybenzoxazole imide of the present invention, an oxidation stabilizer, a filler, a silane coupling agent, an adhesion promoter, a wet heat stabilizer, a crosslinking agent, a terminal sealing agent, a flame retardant, etc. Additives can be added.

<Method for producing positive photosensitive resin composition>
Next, although the manufacturing method of the positive photosensitive resin composition of this invention is demonstrated, this manufacturing method is not limited to the following description. A diazonaphthoquinone (DNQ) photosensitizer is added and dissolved in the hydroxyamide group-containing polyimide of the present invention or its precursor varnish, and this is coated on a substrate, 40 to 120 ° C., preferably 60 to 100 ° C. for 1 minute. The positive photosensitive resin composition film having a film thickness of 0.1 to 20 μm can be obtained by drying with warm air for ˜3 hours.

  The hydroxyamide group-containing polyimide or precursor thereof of the present invention is characterized in that the alkali solubility is appropriately controlled. When a diazonaphthoquinone (DNQ) photosensitizer is not dispersed, it is alkali-soluble, but by containing a DNQ photosensitizer having a dissolution inhibiting action, it becomes alkali-insoluble. When this photosensitive resin composition film is irradiated with ultraviolet rays through a photomask, the DNQ photosensitizer in the exposed area is changed to alkali-soluble indenecarboxylic acid by a photoreaction, so that only the exposed area is soluble in an alkaline aqueous solution. Become. Therefore, a positive pattern can be formed.

  Examples of DNQ-based photosensitizers include 1,2-naphthoquinone-2-diazide-5-sulfonic acid and 1,2-naphthoquinone-2-diazide-4-sulfonic acid low-molecular hydroxy compounds such as 2,3,4-trimethyl. Examples include hydroxybenzophenone, 1,3,5-trihydroxybenzene, 2- and 4-methyl-phenol, esters of 4,4′-hydroxy-propane, and the like.

  When the mixing ratio of the DNQ photosensitizer dispersed in the positive photosensitive resin composition is too small, the difference in solubility between the exposed part and the unexposed part is too small, and it becomes impossible to form a pattern by development. In some cases, the film properties (glass transition temperature, film toughness, thermal stability, etc.) of polybenzoxazole imide, which is the final thermoset, may be adversely affected, and the film may be greatly reduced during the heat curing process. Therefore, the DNQ photosensitizer content is preferably 5 to 40% by weight, more preferably 10 to 30% by weight.

  The film forming step is preferably performed at 120 ° C. or lower. If this temperature is exceeded, the DNQ photosensitizer may start to thermally decompose. For example, when a film is formed at 60 ° C., a large amount of solvent remains in the coating film. In that case, pre-baking at 80 to 120 ° C. for 1 to 30 minutes prior to the exposure step to remove excess solvent is effective in preventing the swelling of the film and the collapse of the fine pattern during development. The solvent can also be extracted and removed by immersing the coating film in water for 1 to 5 minutes.

  The photosensitive resin composition film is irradiated with g-line, h-line, i-line or mixed line of a high-pressure mercury lamp at room temperature for 5 seconds to 1 hour through a photomask, and developed with an alkaline aqueous solution. Examples of alkaline aqueous solutions that can be used for development include organic alkalis such as tetramethylammonium hydroxide (TMAH), triethylamine, and ethanolamine, and inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, and sodium bicarbonate. Can be mentioned. In many electronic devices, residual metals may adversely affect electrical characteristics, so organic alkalis are preferably used, and TMAH aqueous solutions usually used in semiconductor processes are preferably used.

  In this case, the concentration of the TMAH aqueous solution is 0.05 to 10% by weight, preferably 0.1 to 5% by weight, and more preferably, a 2.38% by weight aqueous solution usually used is used as it is for 10 seconds to 10 minutes at room temperature. Further, a clear positive pattern can be obtained by rinsing with pure water.

A water-soluble solvent such as alcohols or glycols can be added to the image liquid and the rinse liquid as necessary.

<Method for producing fine pattern of polybenzoxazole imide>
The fine pattern of the hydroxyamide group-containing polyimide or precursor thereof formed on the substrate as described above is 250 to 400 ° C, preferably 270 to 350 ° C in air, in an inert gas atmosphere such as nitrogen or in vacuum. By heating, a clear pattern of polybenzoxazole imide can be obtained. In this case, if the temperature is lower than 250 ° C., the ring-closing reaction may be incomplete, which is not preferable. If the temperature exceeds 400 ° C., the polybenzoxazole imide may partially be thermally decomposed or melted and the pattern shape may be lost. . The heat curing step is preferably performed in a vacuum or in an inert gas, but may be performed in air if the treatment temperature is not too high.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, it is not limited to these Examples. The physical property values in the following examples were measured by the following methods.
<Infrared absorption line spectrum>
Using a Fourier transform infrared spectrophotometer (FT-IR5300, manufactured by JASCO Corporation), the infrared absorption spectrum of the hydroxyamide group-containing tetracarboxylic dianhydride was measured by the KBr method. Moreover, the infrared absorption spectrum of the hydroxyamide group containing polyimide and the polybenzoxazole imide thin film (film thickness of about 5 micrometers) was measured with the transmission method.
<1H-NMR spectrum>
A 1H-NMR spectrum of the hydroxyamide group-containing tetracarboxylic dianhydride was measured in deuterated dimethyl sulfoxide using a JEOL NMR spectrophotometer (ECP400).
<Intrinsic viscosity>
A solution of 0.5% by weight of a hydroxyamide group-containing polyimide and its precursor was measured at 30 ° C. using an Ostwald viscometer.
<Glass transition temperature: Tg>
Using a thermomechanical analyzer (TMA4000) manufactured by Bruker Ax, the polybenzoxazole imide film (film thickness: about 20 μm) was measured from a loss peak at a frequency of 0.1 Hz and a heating rate of 5 ° C./min by dynamic viscoelasticity measurement. The glass transition temperature was determined.
<Linear thermal expansion coefficient: CTE>
The range of 100 to 200 ° C. from the elongation of the test piece at a load of 0.5 g / film thickness of 1 μm and a heating rate of 5 ° C./min by thermomechanical analysis using a Bruker Ax thermomechanical analyzer (TMA4000). The linear thermal expansion coefficient in the film surface direction of a polybenzoxazole imide film (film thickness of about 20 μm) was determined as an average value at.
<5% weight loss temperature: T _d ⁵ >
Using a Bruker Ax thermogravimetric analyzer (TG-DTA2000), the initial weight of the polybenzoxazole imide film is reduced by 5% in the temperature rising process at 10 ° C./min in nitrogen or air. The temperature was measured. Higher values indicate higher thermal stability.
<Dielectric constant: ε _cal >
Using an Abbe refractometer (Abbe refractometer 4T, using a sodium lamp, wavelength 589 nm) manufactured by Atago Co., Ltd., a direction perpendicular to the direction (n _in ) parallel to the film surface of the polybenzoxazole imide film (20 μm thickness), that is, the film thickness The refractive index in the direction (n _out ) is measured, and based on the average refractive index [n _av = (2 n _in + n _out ) / 3], polybenzoxazole at 1 MHz according to the following formula: ε _cal = 1.1 × n _av ² The dielectric constant (ε _cal ) of the imide film was calculated.
<Water absorption rate>
A polybenzoxazole imide film (film thickness: 20 to 30 μm) vacuum-dried at 50 ° C. for 24 hours was immersed in water at 24 ° C. for 24 hours, and then excess water was wiped off, and the water absorption (%) was determined from the weight increase. .
<Elastic modulus, breaking strength and breaking elongation>
Using a tensile tester (Tensilon UTM-2) manufactured by Toyo Baldwin Co., Ltd., a tensile test (stretching speed: 8 mm / min) was performed on a test piece (3 mm × 30 mm) of a polybenzooxolimide film (film thickness: about 20 μm). Then, the elastic modulus was obtained from the initial gradient of the stress-strain curve, and the elongation at break (%) and the breaking strength were obtained from the elongation rate and stress when the film was broken.
<Light transmittance (transparency)>
Using a UV-visible spectrophotometer (V-530) manufactured by JASCO Corporation, the visible / ultraviolet light transmittance of a hydroxyamide group-containing polyimide film (film thickness: about 10 μm) was measured in the range of 200 nm to 800 nm, and h-line (405 nm ) And g-line (435 nm).
<Cutoff wavelength (transparency)>
Using a UV-Vis spectrophotometer (V-530) manufactured by JASCO Corporation, the visible / ultraviolet ray transmittance of a hydroxyamide group-containing polyimide film (film thickness: about 10 μm) was measured between 200 nm and 900 nm, and the transmittance was 0. The wavelength (cut-off wavelength) of 5% or less was used as an index of transparency. The shorter the cutoff wavelength, the better the transparency of the film.

Example 1
<Synthesis of hydroxyamide group-containing tetracarboxylic dianhydride>
Trimellitic anhydride chloride (22 mmol) was dissolved in dehydrated acetone, and the flask was sealed with a septum cap. Next, ABPS (10 mmol) was taken in another flask, dissolved in dehydrated acetone, and propylene oxide (50 mmol) was added thereto as a deoxidizer. During this reaction, the total solute concentration was 15% by weight. The trimellitic anhydride chloride solution was slowly added dropwise to the ABPS solution with a syringe while cooling in an ice bath in which sodium chloride was dissolved. After completion of dropping, the reaction mixture was stirred for 3 hours. The deposited precipitate was separated by filtration, and excess trimellitic anhydride chloride was dissolved and removed with toluene and hexane. This was vacuum-dried at 40 ° C. for 12 hours to obtain a product with a yield of 72%. From the infrared absorption (FT-IR) spectrum and ¹ H-NMR spectrum, it was confirmed that the product was the target hydroxyamide group-containing tetracarboxylic dianhydride. 1 and 2 show the FT-IR spectrum and ¹ H-NMR spectrum.

(Example 2)
A hydroxyamide group-containing tetracarboxylic dianhydride represented by the formula (2) was synthesized according to the method described in Example 1 except that ADPE was used instead of ABPS.

(Example 3)
<Polymerization of hydroxyamide group-containing polyimide precursor, thermal cyclization, and film property evaluation of polybenzoxazole imide>
In a well-dried sealed reaction vessel with a stirrer, 5 mmol of 4,4′-oxydianiline (hereinafter referred to as ODA) was placed and dissolved in NMP sufficiently dehydrated with Molecular Sieves 4A. 5 mmol of hydroxyamide group-containing tetracarboxylic dianhydride powder described in Example 1 is gradually added. The polymerization reaction was started at a total monomer concentration of 30% by weight. Since the polymerization reaction progressed and the solution viscosity increased and stirring became difficult, the same solvent was added to dilute the total monomer concentration to 20% by weight. Furthermore, it stirred at room temperature for 24 hours and obtained the transparent and uniform and viscous hydroxyamide group containing polyimide precursor varnish. The varnish was appropriately diluted and then refluxed at 160 ° C. for 3 hours in a nitrogen atmosphere to obtain a hydroxyamide group-containing polyimide varnish. From the FT-IR spectrum and ¹ H-NMR spectrum of the product isolated as a powder by dripping it into a large amount of water, the product was completed only for imidization without the ring closure of the hydroxyamide group. This was confirmed to be a hydroxyamide group-containing polyimide. The resulting hydroxyamide group-containing polyimide had an intrinsic viscosity of 0.48 dL / g. The hydroxyamide group-containing polyimide varnish (solvent: NMP, 20 wt%) did not precipitate or gel when stored for 20 days at room temperature, and showed high solution storage stability. The hydroxyamide group-containing polyimide film (thickness: about 10 μm) obtained by applying this varnish to a glass substrate and drying at 60 ° C. for 2 hours showed sufficient light transmittance for h-line and g-line. Similarly, after forming a hydroxyamide group-containing polyimide film on a substrate, heat treatment for ring closure dehydration reaction of the hydroxyamide group is performed at 320 ° C. under reduced pressure for 1 hour, and then peeled off from the substrate to remove residual stress. By performing heat treatment for 1 hour, a polybenzoxazole imide film having a thickness of 20 μm was obtained. This film did not break even in the 180 ° bending test and showed flexibility. As a result of dynamic viscoelasticity measurement of this film, a glass transition point was observed at 323 ° C. The linear thermal expansion coefficient was 49.6 ppm / K. The dielectric constant estimated from the average refractive index was 3.02, and the water absorption was 2.8%. The 5% weight loss temperature was 494 ° C. in nitrogen and 497 ° C. in air, indicating high thermal stability. The mechanical properties were a tensile modulus (Young's modulus) of 3.12 GPa, a breaking strength of 0.12 GPa, and a breaking elongation of 10.4%, indicating sufficient film toughness. Table 1 summarizes these physical property values. 3 and 4 show infrared absorption spectra of the hydroxyamide group-containing polyimide and the polybenzoxazole imide thin film.

Example 4
According to the method described in Example 3, except that 2,2′-bis (trifluoromethyl) benzidi) (hereinafter referred to as TFMB) was used instead of ODA as the diamine component, a hydroxyamide group-containing polyimide precursor was prepared. Polymerization, imidization, film formation, and thermal cyclization produced a polybenzoxazole imide film, and physical properties were similarly evaluated. 5 and 6 show the ¹ H-NMR spectrum of the polyimide containing a hydroxyamide group and the infrared absorption spectrum of the thin film, and FIG. 7 shows the infrared absorption spectrum of the polybenzoxazole imide thin film. The physical property values are shown in Table 1.

(Example 5)
According to the method described in Example 3, except that 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane (hereinafter referred to as HFBAPP) was used instead of ODA as the diamine component. A group-containing polyimide precursor was polymerized, imidized, formed into a film, and thermally cyclized to produce a polybenzoxazole imide film, and the physical properties were similarly evaluated. 8 and 9 show infrared absorption spectra of the hydroxyamide group-containing polyimide and polybenzoxazole imide thin film. The physical property values are shown in Table 1.

Abbreviations in Table 1 represent the following.
η _inh : intrinsic viscosity Tg: glass transition temperature CTE: linear expansion coefficient T _d ⁵ N ₂ : 5% weight reduction temperature in nitrogen T _d ⁵ air: 5% weight reduction temperature in air T% ₄₀₅ : at 405 nm light transmittance _T% 435: light transmission cut-off in 435 nm: cut-off wavelength W _A: water absorption E _b: elongation at break the modulus: tensile modulus

(Example 6)
<Positive pattern formation>
A hydroxyamide group-containing polyimide precursor was polymerized according to the method described in Example 3 except that both ODA and HFBAPP were used instead of ODA alone as the diamine component (copolymerization molar ratio ODA: HFBAPP = 75: 25). This was imidized to obtain a hydroxyamide group-containing polyimide. To this varnish, 2,3,4-tris (1-oxo-2-diazonaphthoquinone-5-sulfoxy) benzophenone (NT-200, manufactured by Toyo Gosei Co., Ltd.) as a diazonaphthoquinone photosensitizer It was added and dissolved so as to be 30% by weight with respect to the amount. This was apply | coated on the glass substrate surface-treated with the silane coupling agent, and it was made to dry in a hot air dryer at 60 degreeC for 2 hours, and the photosensitive resin composition film with a film thickness of 5 micrometers was obtained. This was pre-baked at 100 ° C. for 10 minutes, and then a 20-line mixed line (irradiated light intensity at 365 nm = about 150 mW / cm ² ) of an epi-illumination type high-pressure mercury lamp (Toscure 251 manufactured by Harrison Toshiba Lighting Co.) was passed through a photomask. Irradiated for 2 seconds. This was developed with a 2.38 wt% TMAH aqueous solution containing 10 wt% of 2-propanol at 23 ° C. for 25 seconds, rinsed with water, dried at 60 ° C. for several minutes, and a clear relief pattern with a line width of 20 μm was obtained. Obtained. Also, no pattern collapse was observed after the thermal cyclization reaction. FIG. 10 shows a scanning electron micrograph of the positive pattern obtained. When the hydroxyamide group-containing polyimide described in Example 5 was used, a clear positive pattern was similarly obtained.

(Comparative Example 1)
In place of the hydroxyamide group-containing tetracarboxylic dianhydride described in Example 1, 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride, which is a similar compound, was used. A polyimide precursor was obtained using the diamine. Using this, a photosensitive film was produced according to the method described in Example 6 and pattern formation was attempted. However, the difference in alkali solubility between the exposed and unexposed areas was insufficient, and pattern formation was difficult. Met. Further, when an imidized polyimide precursor was used, the alkali dissolution rate was slow, and pattern formation was similarly difficult. These results are because the hydroxyamide group-containing tetracarboxylic dianhydride of the present invention was not used.

(Comparative Example 2)
In place of the hydroxyamide group-containing tetracarboxylic dianhydride described in Example 1, a tetracarboxylic dianhydride other than the present invention represented by the formula (9), which is an analogous compound, was used and described in Example 3. According to the method, a hydroxyamide group-containing polyimide outside the present invention was polymerized. Intrinsic viscosity was 0.27 dL / g. Using this, a film (film thickness of about 10 μm) was produced according to the method described in Example 3. This film was extremely fragile. This is because the intrinsic viscosity is low and the molecular weight is not sufficiently high. Further, the light transmittances of the film at h-line and g-line were 1.6% and 37.0%, respectively, which were insufficient. This is because the hydroxyamide group-containing tetracarboxylic dianhydride of the present invention was not used during the polymerization.

FT-IR spectrum of the hydroxyamide group-containing tetracarboxylic dianhydride obtained in Example 1 ¹ H-NMR spectrum of the hydroxyamide group-containing tetracarboxylic dianhydride obtained in Example 1 Infrared absorption spectrum of the hydroxyamide group-containing polyimide obtained in Example 3 Infrared absorption spectrum of the polybenzoxazole imide thin film obtained in Example 3 ¹ H-NMR spectrum of the hydroxyamide group-containing polyimide obtained in Example 4 Infrared absorption spectrum of the hydroxyamide group-containing polyimide thin film obtained in Example 4 Infrared absorption spectrum of the polybenzoxazole imide thin film obtained in Example 4 Infrared absorption spectrum of the hydroxyamide group-containing polyimide obtained in Example 5 Infrared absorption spectrum of the polybenzoxazole imide thin film obtained in Example 5 Scanning electron micrograph of the positive pattern obtained in Example 6

Claims (14)

A hydroxyamide group-containing tetracarboxylic dianhydride represented by the following formula (1):

A hydroxyamide group-containing tetracarboxylic dianhydride represented by the following formula (2):

The following formula (3):

A hydroxyamide group-containing polyimide precursor containing a repeating unit represented by: (In formula (3), A is represented by the following formula (4) or (5), and B represents a divalent aromatic group or aliphatic group.)

The hydroxyamide group-containing polyimide precursor according to claim 3, wherein the intrinsic viscosity is 0.4 dL / g or more. The following formula (6):

A hydroxyamide group-containing polyimide containing a repeating unit represented by: (In Formula (6), A and B represent the same meaning as in Formula (3).) The hydroxyamide group-containing polyimide according to claim 5, wherein the intrinsic viscosity is 0.4 dL / g or more. The hydroxyamide group-containing polyimide according to claim 5 or 6, wherein the light transmittance of a cast film (film thickness: 10 µm) at 435 nm (g line) and 405 nm (h line) is 50% or more and 10% or more, respectively. The following formula (7):

A polybenzoxazole imide containing a repeating unit represented by: (In Formula (7), A and B represent the same meaning as in Formula (3).)   The polybenzoxazole imide according to claim 8, which has a glass transition temperature of 300 ° C. or higher.   The hydroxyamide group according to any one of claims 5 to 7, wherein the hydroxyamide group-containing polyimide precursor according to claim 3 or 4 is subjected to an imidization reaction by heating or using a dehydrating cyclization reagent. The manufacturing method of a containing polyimide.   The hydroxyamide group-containing polyimide precursor according to claim 3 or 4 or the hydroxyamide group-containing polyimide according to any one of claims 5 to 7 is subjected to a dehydration ring-closing reaction by heating or using a dehydration cyclization reagent. A process for producing a polybenzoxazole imide according to claim 8 or 9. A positive photosensitive resin comprising the hydroxyamide group-containing polyimide precursor according to claim 3 or 4, or the hydroxyamide group-containing polyimide according to any one of claims 5 to 7 and a diazonaphthoquinone photosensitizer. Resin composition. A fine pattern obtained by treating a film comprising the photosensitive resin composition according to claim 12 with patterning exposure and alkali development, followed by heating or a dehydrating cyclization reagent. The protective film of the semiconductor element formed by containing the polybenzoxazole imide of Claim 8 or 9.

Images