KR102522475B1 - Positive photosensitive resin composition, dry film, cured product, printed wiring board and semiconductor device - Google Patents

Abstract

A positive photosensitive resin composition having excellent developability (resolution and remaining film rate) and excellent pattern formation after curing, a dry film having a resin layer obtained from the composition, and a cured product of the resin layer of the composition or the dry film , a printed wiring board having the cured product and a semiconductor device having the cured product. (A) a polybenzoxazole precursor, (B) a photoacid generator, (C) a crosslinking agent having a phenolic hydroxyl group, and (D) a crosslinking agent having no phenolic hydroxyl group and having two or more methylol groups. It is a positive type photosensitive resin composition etc. which are made into.

Description

Positive photosensitive resin composition, dry film, cured product, printed wiring board and semiconductor device

The present invention relates to a positive photosensitive resin composition, a dry film, a cured product, a printed wiring board and a semiconductor element.

As a positive type photosensitive resin composition developable with an alkaline aqueous solution, a composition in which a polybenzoxazole (PBO) precursor and a photoacid generator such as a naphthoquinonediazide compound are blended is used. Since the polybenzoxazole cured product obtained by thermally curing such a composition is excellent in heat resistance and electrical insulation, it is a surface protective film or an interlayer insulating film of electrical materials, such as a coating film of semiconductor elements, a flexible printed wiring board material, or a heat-resistant insulating interlayer. The application of the material is in progress.

In the positive photosensitive resin composition containing such a polybenzoxazole precursor as a resin component, when the molecular weight of the polybenzoxazole precursor is high, the cured product thereof can obtain excellent mechanical properties. On the other hand, however, since the resin component is a high molecular weight material, there has been a problem that the coating film developability of such a composition is lowered.

In contrast, conventionally, in a positive photosensitive resin composition containing a high molecular weight body such as a polybenzoxazole precursor as a resin component, a dissolution accelerator has been added in order to improve the developability of a coating film (for example, Patent Document 1 ).

Certainly, according to the prior art, the developability of the coating film is improved by adding a dissolution accelerator, but the present inventors have found that there is a new problem that control of the pattern shape becomes difficult.

On the other hand, in order to improve the developability of the coating film, a method of lowering the molecular weight of the resin component can be considered. However, the present inventors have found that in this method, while the remaining film rate at the time of development decreases, there are various problems that the pattern shape is deformed after curing and control of the rectangularity becomes difficult.

Japanese Unexamined Patent Publication No. 2009-145900

Therefore, the main object of the present invention is to provide a positive photosensitive resin composition having excellent developability (resolution and remaining film rate) and excellent pattern formation after curing, and a dry film having a resin layer of the composition. .

Another object of the present invention is to provide a cured product of the resin layer of the composition or dry film suitable for use in electronic parts such as printed wiring boards and semiconductor devices.

As a result of intensive studies in view of the above, the present inventors have found that the above problems can be solved by using two specific types of compounds as a crosslinking agent, and have completed the present invention.

That is, the positive photosensitive resin composition of the present invention comprises (A) a polybenzoxazole precursor, (B) a photoacid generator, (C) a crosslinking agent having a phenolic hydroxyl group, and (D) a methyl It is characterized by including a crosslinking agent having two or more all groups.

It is preferable that the positive type photosensitive resin composition of this invention contains a silane coupling agent further.

The dry film of this invention is characterized by having a resin layer obtained by apply|coating and drying the said positive type photosensitive resin composition on a film.

The cured product of the present invention is obtained by curing the positive photosensitive resin composition or the resin layer of the dry film.

The printed wiring board of the present invention is characterized by having the above cured product.

The semiconductor element of the present invention is characterized by having the above cured product.

ADVANTAGE OF THE INVENTION According to this invention, the positive type photosensitive resin composition which has excellent developability (resolution and remaining film rate) and is excellent in pattern formation property after hardening can be provided. As a result, the positive photosensitive resin composition of the present invention, the dry film obtained from the composition, and the cured product of the resin layer of the composition or the dry film can be suitably used for electronic parts such as printed wiring boards and semiconductor elements.

Hereinafter, the components contained in the positive photosensitive resin composition of the present invention are explained in detail.

[(A) Polybenzoxazole Precursor]

The positive type photosensitive resin composition of this invention contains the (A) polybenzoxazole precursor. (A) The method for synthesizing the polybenzoxazole precursor is not particularly limited, and may be synthesized by a known method. For example, it can be obtained by reacting dihydroxydiamines as an amine component with dihalides of dicarboxylic acids such as dicarboxylic acid dichloride as an acid component.

(A) The polybenzoxazole precursor is preferably a polyhydroxyamic acid having the following repeating structure.

(In the formula, X represents a tetravalent organic group, Y represents a divalent organic group. n is an integer greater than or equal to 1, preferably 10 to 50, more preferably 20 to 40.)

(A) In the case of synthesizing the polybenzoxazole precursor by the above method, in the general formula (1), X is a residue of the dihydroxydiamines and Y is a residue of the dicarboxylic acid.

Examples of the dihydroxydiamines include 3,3'-diamino-4,4'-dihydroxybiphenyl, 4,4'-diamino-3,3'-dihydroxybiphenyl, and bis(3- Amino-4-hydroxyphenyl)propane, bis(4-amino-3-hydroxyphenyl)propane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3-hydroxyphenyl) Sulfone, 2,2-bis(3-amino-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(4-amino-3-hydroxy Phenyl) -1,1,1,3,3,3-hexafluoropropane etc. are mentioned. Among them, 2,2-bis(3-amino-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane is preferable.

As the dicarboxylic acid, isophthalic acid, terephthalic acid, 5-tert-butyl isophthalic acid, 5-bromoisophthalic acid, 5-fluoroisophthalic acid, 5-chloroisophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-dicarboxybiphenyl, 4,4'-dicarboxydiphenyl ether, 4,4'-dicarboxytetraphenylsilane, bis(4-carboxyphenyl)sulfone, 2,2-bis(p-carboxy dicarboxylic acids having an aromatic ring such as phenyl) propane, 2,2-bis(4-carboxyphenyl)-1,1,1,3,3,3-hexafluoropropane, oxalic acid, malonic acid, succinic acid, and aliphatic dicarboxylic acids such as 1,2-cyclobutanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, and 1,3-cyclopentanedicarboxylic acid. Among them, 4,4'-dicarboxydiphenyl ether is preferable.

In the general formula (1), the tetravalent organic group represented by X may be an aliphatic group or an aromatic group, but it is preferably an aromatic group, and two hydroxyl groups and two amino groups are ortho-positioned on an aromatic ring. It is more preferable. It is preferable that it is 6-30, and, as for the number of carbon atoms of the said tetravalent aromatic group, it is more preferable that it is 6-24. Although the following groups are mentioned as a specific example of the said tetravalent aromatic group, It is not limited to these, What is necessary is just to select a well-known aromatic group which can be contained in a polybenzoxazole precursor according to a use.

Among the aromatic groups, the tetravalent aromatic group is preferably one of the following groups.

In the general formula (1), the divalent organic group represented by Y may be either an aliphatic group or an aromatic group, but is preferably an aromatic group, and is more preferably bonded to the carbonyl in the general formula (1) on the aromatic ring. It is preferable that it is 6-30, and, as for the number of carbon atoms of the said divalent aromatic group, it is more preferable that it is 6-24. Although the following groups are mentioned as a specific example of the said divalent aromatic group, It is not limited to these, What is necessary is just to select the well-known aromatic group contained in a polybenzoxazole precursor according to a use.

(Wherein, A is a single bond, -CH ₂ -, -O-, -CO-, -S-, -SO ₂ -, -NHCO-, -C(CF ₃ ) ₂ -, -C(CH ₃ ) represents a divalent group selected from the group consisting of _2- .)

Among the above aromatic groups, the divalent organic group is preferably the following group.

(A) The polybenzoxazole precursor may contain 2 or more types of repeating structures of the said polyhydroxyamic acid. Further, structures other than the repeating structure of the polyhydroxyamic acid may be included, for example, the repeating structure of polyamic acid may be included.

(A) It is preferable that it is 5,000-100,000, and, as for the number average molecular weight (Mn) of a polybenzoxazole precursor, it is more preferable that it is 8,000-50,000. Here, the number average molecular weight is a numerical value measured by GPC and converted into standard polystyrene. Moreover, it is preferable that it is 10,000-200,000, and, as for the weight average molecular weight (Mw) of (A) polybenzoxazole precursor, it is more preferable that it is 16,000-100,000. Here, the weight average molecular weight is a numerical value measured by GPC and converted into standard polystyrene. It is preferable that it is 1-5, and, as for Mw/Mn, it is more preferable that it is 1-3.

(A) A polybenzoxazole precursor may be used individually by 1 type, and may be used in combination of 2 or more type. (A) It is preferable that the compounding quantity of a polybenzoxazole precursor is 60-90 mass % based on the total solid content of a composition.

[(B) photoacid generator]

(B) As the photoacid generator, naphthoquinonediazide compounds, diarylsulfonium salts, triarylsulfonium salts, dialkylphenacylsulfonium salts, diaryliodonium salts, aryldiazonium salts, aromatic tetracarboxylic acid esters , aromatic sulfonic acid esters, nitrobenzyl esters, aromatic N-oxyimidosulfonates, aromatic sulfamides, benzoquinone diazosulfonic acid esters, and the like. (B) The photoacid generator is preferably a dissolution inhibitor. Among them, a naphthoquinonediazide compound is preferable.

As a naphthoquinonediazide compound, specifically, for example, a naphthoquinonediazide adduct of tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene (for example, Sanbo Chemical Co., Ltd.) TKF-520, TKF-528, TKF-420, TKF-428 manufactured by Kyusho Co., Ltd.) or naphthoquinonediazide adducts of tetrahydroxybenzophenone (e.g., BS550, BS570 manufactured by Sanbo Chemical Co., Ltd., BS570; BS599), etc. can be used. Here, what is necessary is just to add naphthoquinonediazide, for example by reacting o-quinonediazide sulfonyl chloride with a hydroxy compound or an amino compound.

(B) The photoacid generator may be used individually by 1 type, or may be used in combination of 2 or more type. (B) The blending amount of the photoacid generator is preferably 3 to 20% by mass based on the total solid content of the composition.

[(C) Crosslinking Agent Having a Phenolic Hydroxyl Group]

The positive type photosensitive resin composition of this invention contains (C) the crosslinking agent which has a phenolic hydroxyl group as a crosslinking agent. (C) The crosslinking agent having a phenolic hydroxyl group is not particularly limited, but preferably has two or more hydroxyl groups (including a phenolic hydroxyl group), more preferably has two or more phenolic hydroxyl groups, and has the following general formula (2) It is more preferable that it is a compound represented by

(In formula (2), R ¹ represents a 2-10 valent organic group. R ² each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n represents an integer of 2 to 10.)

In the said General formula (2), it is preferable that R ^<1> is a C1-C3 alkylene group which may have a substituent.

In the above general formula (2), it is preferable that R ² is a hydrogen atom.

In the said general formula (2), it is preferable that n is an integer of 2-4, and it is more preferable that it is 2.

Moreover, (C) the crosslinking agent having a phenolic hydroxyl group preferably has a fluorine atom, and more preferably has a trifluoromethyl group. The fluorine atom or the trifluoromethyl group preferably has a 2- to 10-valent organic group represented by R ¹ in the general formula (2), and R ¹ is preferably a di(trifluoromethyl)methylene group. Further, (C) the crosslinking agent having a phenolic hydroxyl group preferably has a bisphenol structure, and more preferably has a bisphenol AF structure.

(C) It is preferable that it is the following compound as a specific example of the crosslinking agent which has a phenolic hydroxyl group.

(C) The crosslinking agent having a phenolic hydroxyl group may be used individually by 1 type, or may be used in combination of 2 or more type. (C) It is preferable that it is 1-20 mass %, and, as for the compounding quantity of the crosslinking agent which has a phenolic hydroxyl group, it is more preferable that it is 3-10 mass % based on the total solid content of a composition. In such a blending ratio, a composition having more excellent developability and better pattern formation after curing can be obtained.

[(D) A crosslinking agent having no phenolic hydroxyl group and two or more methylol groups]

The positive type photosensitive resin composition of this invention contains (D) the crosslinking agent which does not have a phenolic hydroxyl group but has two or more methylol groups as a crosslinking agent. It is preferable that the molecular weight of this (D) crosslinking agent which does not have a phenolic hydroxyl group but has two or more methylol groups is 100 or more.

(D) It is more preferable that the crosslinking agent which does not have a phenolic hydroxyl group and has two or more methylol groups is a compound represented by the following general formula (3).

(In formula (3), n represents an integer of 1 to 10, when n is 1, R ³ represents a methylol group (ie, “-CH ₂ OH”), and when n is an integer of 2 to 10, R ³ represents an organic group of 2 to 10. R ⁴ each independently represents an organic group of 1 to 4 carbon atoms. m1 represents an integer of 1 to 5, and m2 represents an integer of 0 to 4.)

In the general formula (3), n is preferably 1.

In the said general formula (3), it is preferable that it is a C1-C4 alkyl group, and, as for R ^<4> , it is more preferable that it is a methyl group.

(D) It is preferable that it is the following compound as a specific example of the crosslinking agent which does not have a phenolic hydroxyl group but has two or more methylol groups.

(D) The crosslinking agent which does not have a phenolic hydroxyl group and has two or more methylol groups may be used individually by 1 type, and may be used in combination of 2 or more type. The blending amount of the (D) crosslinking agent having no phenolic hydroxyl group and two or more methylol groups is preferably 1 to 20% by mass, more preferably 3 to 10% by mass, based on the total solid content of the composition. In such a blending ratio, a composition having more excellent developability and better pattern formation after curing can be obtained.

The two types of crosslinking agents described above are (C) a crosslinking agent having a phenolic hydroxyl group has a function of promoting dissolution, and (D) a crosslinking agent having no phenolic hydroxyl group and having two or more methylol groups has a function of inhibiting dissolution. have For this reason, in order to obtain better developability (resolution and remaining film ratio), the blending ratio thereof is preferably (C):(D) = 0.3 to 1:1 to 0.3, more preferably 4:6 to 6 :4, more preferably (C):(D) = 1:1.

(Silane coupling agent)

The positive photosensitive resin composition of the present invention may also contain a silane coupling agent. Adhesion with a base material can be improved by including a silane coupling agent. The silane coupling agent is not particularly limited, and examples thereof include a silane coupling agent having an alkoxy group, a silane coupling agent having an amino group, a silane coupling agent having a mercapto group, a silane coupling agent having an epoxy group, a silane coupling agent having an ethylenically unsaturated group, The silane coupling agent etc. which have an arylamino group are mentioned.

These silane coupling agents may be used individually by 1 type, and may be used in combination of 2 or more type. It is preferable that the compounding quantity of this silane coupling agent is 1-15 mass % based on the total solid content of a composition. If it is 1 to 15% by mass, it is possible to prevent development residues in the exposed portion while ensuring adhesion to the substrate.

Other components which can be incorporated into the positive photosensitive resin composition of the present invention will be described below.

A solvent can be mix|blended with the positive type photosensitive resin composition of this invention. As the solvent, (A) a polybenzoxazole precursor, (B) a photoacid generator, (C) a crosslinking agent having a phenolic hydroxyl group, (D) a crosslinking agent having two or more methylol groups without having a phenolic hydroxyl group, and others It will not specifically limit if it dissolves an additive. As an example, N,N'-dimethylformamide, N-methylpyrrolidone, N-ethyl-2-pyrrolidone, N,N'-dimethylacetamide, diethylene glycol dimethyl ether, cyclopentanone, γ- Butyrolactone, α-acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, dimethylsulfoxide, hexamethylphosphorus Amide, pyridine, (gamma)-butyrolactone, and diethylene glycol monomethyl ether are mentioned.

These solvents may be used individually by 1 type, or may be used in mixture of 2 or more types. The compounding amount of this solvent can be used in the range of 50 to 9000 parts by mass with respect to 100 parts by mass of the polybenzoxazole precursor (A) depending on the coating film thickness and viscosity.

A known sensitizer may be incorporated into the positive photosensitive resin composition of the present invention in order to further improve photosensitivity.

In addition, a known adhesion adjuvant may be added to the positive photosensitive resin composition of the present invention to improve adhesion to a substrate.

In order to impart processing characteristics and various functionalities to the positive photosensitive resin composition of the present invention, various other organic or inorganic low-molecular or high-molecular compounds may be blended. For example, surfactants, leveling agents, plasticizers, fine particles and the like can be used. The fine particles include organic fine particles such as polystyrene and polytetrafluoroethylene, and inorganic fine particles such as colloidal silica, carbon, and layered silicate. Further, various colorants and fibers may be blended with the positive photosensitive resin composition of the present invention.

[Dry Film]

The dry film of this invention has a resin layer obtained by apply|coating and drying the positive photosensitive resin composition of this invention on a film. The dry film of the present invention is used by laminating a resin layer so as to be in contact with a substrate.

The dry film of the present invention is obtained by uniformly applying the positive photosensitive resin composition of the present invention to a carrier film by an appropriate method such as a blade coater, lip coater, comma coater, or film coater, and drying the It can be manufactured by forming a stratum and preferably laminating a cover film thereon. The cover film and the carrier film may be of the same film material or may use different films.

In the dry film of the present invention, as the film material of the carrier film and the cover film, those known as those used for dry films can all be used.

As the carrier film, thermoplastic films such as polyester films such as polyethylene terephthalate having a thickness of 2 to 150 µm are used, for example.

Although a polyethylene film, a polypropylene film, etc. can be used as a cover film, the adhesive force with a resin layer is smaller than a carrier film is preferable.

The film thickness of the resin layer on the dry film of the present invention is preferably 100 µm or less, and more preferably in the range of 5 to 50 µm.

Using the positive photosensitive resin composition of the present invention, a pattern film that is a cured product thereof is prepared, for example, as follows.

First, as step 1, a coating film is obtained by applying a positive photosensitive resin composition onto a substrate, drying it, or transferring a resin layer from a dry film onto a substrate.

As a method of applying a positive photosensitive resin composition onto a substrate, a method that has conventionally been used for application of a photosensitive resin composition, for example, a method of applying with a spin coater, bar coater, blade coater, curtain coater, screen printer, etc., spray A method of spray coating with a coater, furthermore, an inkjet method or the like can be used.

As a method of drying the coating film, methods such as air drying, heat drying by an oven or hot plate, and vacuum drying are used. Drying of this coating film is preferably performed under conditions in which ring closure of the (A) polybenzoxazole precursor in the photosensitive resin composition does not occur. Specifically, natural drying, blowing drying, or heat drying can be performed under conditions of 1 to 30 minutes at 70 to 140°C. Preferably, drying is performed for 1 to 20 minutes on a hot plate. Further, vacuum drying is also possible, and in this case, it can be performed at room temperature for 20 minutes to 1 hour.

The substrate is not particularly limited, and it can be widely applied to semiconductor substrates such as silicon wafers, wiring boards, various resins, metals, and the like.

Then, as step 2, the coating film is exposed through a photomask having a pattern or directly.

As the exposure light beam, (B) a light having a wavelength capable of activating the photo-acid generator and generating an acid is used. Specifically, the maximum wavelength of the exposure light beam is preferably in the range of 350 to 450 nm. As described above, if a sensitizer is appropriately used, the photosensitivity can be adjusted.

As an exposure apparatus, a contact aligner, a mirror projection, a stepper, a laser direct exposure apparatus, etc. can be used.

Then, as step 3, you may heat and ring-close a part of (A) polybenzoxazole of an unexposed part.

Here, the exchange rate is about 30%. The heating time and heating temperature are appropriately changed depending on the type of (A) polybenzoxazole, coating film thickness, and (B) photoacid generator.

Next, as step 4, the coating film is treated with a developing solution.

Thereby, the exposed part in the coating film can be removed, and the pattern film of the positive type photosensitive resin composition of this invention can be formed.

As a method used for development, any method can be selected from conventionally known photoresist developing methods, such as a rotary spray method, a paddle method, an immersion method involving ultrasonic treatment, and the like.

Examples of the developing solution include inorganic alkalis such as sodium hydroxide, sodium carbonate, sodium silicate and aqueous ammonia; organic amines such as ethylamine, diethylamine, triethylamine and triethanolamine; tetramethylammonium hydroxide and tetrabutylammonium hydroxide; Aqueous solutions, such as a quaternary ammonium salt of , are mentioned. Moreover, you may add an appropriate amount of water-soluble organic solvents, such as methanol, ethanol, and isopropyl alcohol, and surfactant to these as needed. Moreover, you may use the said solvent as a developing solution.

Thereafter, the coated film is washed with a rinse liquid as needed to obtain a patterned film.

As a rinse liquid, distilled water, methanol, ethanol, isopropyl alcohol, etc. can be used individually or in combination.

After that, as step 5, the patterned film is heated to obtain a cured coating film (cured product).

At this time, (A) What is necessary is just to ring-close the polybenzoxazole precursor and obtain polybenzoxazole.

The heating temperature is appropriately set so that the patterned film of polybenzoxazole can be cured. For example, heating is performed at 150 to 350°C for about 5 to 120 minutes in an inert gas. A more preferable range of the heating temperature is 200 to 320°C.

This heating is performed by using, for example, a hot plate, an oven, or a heating oven capable of setting a temperature program. As the atmosphere (gas) at this time, air may be used, or an inert gas such as nitrogen or argon may be used.

The use of the positive photosensitive resin composition of the present invention is not particularly limited, and examples thereof include printing inks, adhesives, fillers, electronic materials, optical circuit parts, molding materials, resist materials, building materials, three-dimensional modeling, optical members, etc. , various well-known fields and products in which resin materials are used. In particular, a wide range of fields and products in which properties such as heat resistance, dimensional stability, and insulation of polybenzoxazole films are effective, such as paints or printing inks, color filters, films for flexible displays, coatings of semiconductor devices, electronic parts, and interlayers. It is suitably used as a forming material for coating films of printed wiring boards such as insulating films and solder resists, optical circuits, optical circuit components, antireflection films, holograms, optical members, or building materials.

In particular, the positive photosensitive resin composition of the present invention is mainly used as a pattern formation material (resist), and the pattern film formed thereby functions as a component that imparts heat resistance and insulation as a permanent film containing polybenzoxazole. For example, color filters, films for flexible displays, insulating materials for passive components, coatings of semiconductor devices, interlayer insulation films, coatings of printed wiring boards such as solder resists and cover coatings, solder dams, optical circuits, optical circuit components, and reflections. It is suitable for forming a protective film, other optical members or electronic members.

Example

Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to the following examples. In the following, "part" and "%" are all based on mass unless otherwise specified.

(Synthesis of polybenzoxazole (PBO) precursor)

Into a 0.5 liter flask equipped with a stirrer and a thermometer, 212 g of N-methylpyrrolidone was charged, and 17.55 g (47.93 mmol) of bis(3-amino-4-hydroxyamidophenyl)hexafluoropropane was stirred and dissolved. Thereafter, the flask was immersed in an ice bath, and 15.00 g (50.83 mmol) of 4,4'-diphenyl ether dicarboxylic acid chloride was added as a solid at 5 g each for 30 minutes while maintaining the inside of the flask at 0 to 5 ° C. It was added and stirred for 30 minutes in an ice bath. After that, stirring was continued at room temperature for 5 hours. The stirred solution was poured into 1 L of ion-exchanged water (resistivity value: 18.2 MΩ·cm), and precipitates were recovered. Then, the obtained solid was dissolved in 420 mL of acetone, and injected into 1 L of ion-exchanged water. After recovering the precipitated object, it was dried under reduced pressure to obtain a polybenzoxazole (PBO) precursor A-1 having the following repeating structure at the carboxyl group terminal. The number average molecular weight (Mn) of the polybenzoxazole precursor A-1 was 17,300, the weight average molecular weight (Mw) was 42,100, and Mw/Mn was 2.45.

(Examples 1 to 7, Comparative Examples 1 to 3)

Based on 100 parts by mass of the benzoxazole precursor (A-1) synthesized above, 10 parts by mass of the naphthoquinonediazide (DNQ) compound (B-1), the crosslinking agent shown in Table 1 below, and the silane coupling agent (E- 1) After blending 7 parts by mass, N-methylpyrrolidone (NMP) was added so that the benzoxazole precursor was 30% by mass to obtain a varnish, which was applied on a silicon substrate using a spin coater. It was made to dry on a hot plate at 120 degreeC for 3 minutes, and the dried film of the photosensitive resin composition was obtained. The obtained dry film was irradiated with broad light of 300 mJ/cm ² through a mask having a pattern of 1 to 30 μm using a high-pressure mercury lamp. After exposure, it was developed for 60 seconds with a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution, rinsed with water, and a positive pattern was obtained.

(B-1), (C-1), (C-2), (C-3), (D-1), (D-2), (D-3), (E-1) are the following compounds am.

(Evaluation of remaining film rate of unexposed area)

The film thickness of the photosensitive film after development was measured, and the remaining film ratio of the unexposed area was determined by taking a ratio with the film thickness before development.

(Evaluation of Resolution)

After development, the pattern was observed with an electron microscope (SEM "JSM-6010"), and the resolution (L (μm) / S (μm)) was the size of the minimum pattern capable of patterning the exposed portion without scum.

(pattern formation after curing)

The positive pattern was cured by heat treatment at 150°C for 30 minutes/320°C for 1 hour, and then the pattern shape was observed with an electron microscope (SEM "JSM-6010") and evaluated according to the following criteria.

○: When the pattern shape is a rectangle or a shape close to a rectangle

×: When the pattern shape has no angles and is close to a circular shape

Numerical values in parentheses in the table indicate the blending amount (parts by mass) of each component.

From the results shown in Table 1, it can be seen that the positive photosensitive resin composition of the present invention containing the above specific two types of crosslinking agents is excellent in resolution and film remaining rate, and can form positive patterns with excellent shapes. In particular, it can be seen that the balance of the evaluation results regarding the remaining film ratio, resolution and pattern shape of the unexposed area is the best when the blending ratio of (C-1) and (D-1) in Example 1 is 1:1.

Claims (6)

(A) a polybenzoxazole precursor;
(B) a photoacid generator;
(C) a crosslinking agent having a phenolic hydroxyl group, and
(D) A crosslinking agent having two or more methylol groups without a phenolic hydroxyl group
A positive photosensitive resin composition comprising a,
A positive photosensitive resin composition, characterized in that the (C) crosslinking agent having a phenolic hydroxyl group is any of the following compounds.

The positive photosensitive resin composition according to claim 1, further comprising a silane coupling agent. A dry film characterized by having a resin layer obtained by applying the positive photosensitive resin composition according to claim 1 to a film and drying it. A cured product obtained by curing the resin layer of the positive photosensitive resin composition according to claim 1 or 2 or the dry film according to claim 3. A printed wiring board comprising the cured product according to claim 4. A semiconductor device comprising the cured product according to claim 4.