WO2022270544A1

WO2022270544A1 - Negative photosensitive resin composition, negative photosensitive polmer, cured film and semiconductor device

Info

Publication number: WO2022270544A1
Application number: PCT/JP2022/024905
Authority: WO
Inventors: 啓太今井; 数矢中島
Original assignee: 住友ベークライト株式会社
Priority date: 2021-06-25
Filing date: 2022-06-22
Publication date: 2022-12-29
Also published as: TW202311367A; JPWO2022270544A1

Abstract

A negative photosensitive resin composition according to the present invention contains (A) a polyimide, (B) a crosslinking agent that contains a multifunctional (meth)acrylate, and (C) a photopolymerization initiator; and the polyimide (A) comprises a structural unit (a1) represented by general formula (a1) and a structural unit (a2) represented by general formula (a2). (In general formula (a1), each Y represents a group that is selected from among groups represented by general formula (a1-1), general formula (a1-2) and general formula (a1-3); and the plurality of Y moieties may be the same as or different from each other.)

Description

Negative photosensitive resin composition, negative photosensitive polymer, cured film and semiconductor device

The present invention relates to a negative photosensitive resin composition, a negative photosensitive polymer, a cured film and a semiconductor device.

Polyimide resin has high mechanical strength, heat resistance, insulation, and solvent resistance, so it is widely used as a protective material for liquid crystal display elements and semiconductors, as an insulating material, and as a thin film for electronic materials such as color filters. there is

Patent Document 1 discloses a block copolyimide that is soluble in a dipolar aprotic solvent, and states that a predetermined acid anhydride can be used to obtain the block copolyimide.

Patent Document 2 discloses a polyimide resin composed of structural units having a predetermined structure. This document describes an example of synthesizing a polyimide resin using 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane.

Patent Document 3 discloses an aromatic tetracarboxylic dianhydride, 4,4'-diaminodiphenylmethane having at least one or more alkyl groups in an aromatic ring having an amino group, and p-aminobenzoic acid ester groups at both ends. A polyimide elastomer resin is disclosed which is a terpolymer obtained from a polyether oligomer having a specific molecular weight. The document mentions bis(4-amino-3-ethyl-5-methylphenyl)methane as 4,4'-diaminodiphenylmethane. The document describes that the resin has excellent heat and humidity resistance.

Patent Document 4 discloses a block copolymer consisting of a polyimide structural unit formed from an aromatic tetracarboxylic dianhydride and a 4,4'-diaminodiphenylmethane derivative and a dimethylsiloxane structural unit. The document mentions bis(4-amino-3-ethyl-5-methylphenyl)methane as 4,4'-diaminodiphenylmethane. The literature describes that the resin is excellent in heat resistance and solvent solubility.

International Publication No. 015/091122 Australia JP-A-64-16829 JP-A-8-217874 JP-A-9-40777

However, in the conventional techniques described in Patent Documents 1 to 4, the film containing polyimide obtained from the photosensitive resin composition has room for improvement in mechanical strength such as elongation.

Conventionally, in order to improve the solubility of polyimide in organic solvents, fluorine atoms have been introduced into the skeleton of the polyimide. When synthesized, it was found that the strong electron-withdrawing property of fluorine atoms affects the electrons of the imide ring, making the resulting polyimide susceptible to hydrolysis, which reduces mechanical strength such as elongation.
That is, conventional polyimides have room for improvement in terms of the balance between solubility in organic solvents and mechanical strength such as elongation.

The present inventors have found that the above problems can be solved by using a polyimide having a specific structure, and completed the present invention.
That is, the present invention can be shown below.

[1] (A) polyimide;
(B) a cross-linking agent comprising a polyfunctional (meth)acrylate;
(C) a photoinitiator;
including
Polyimide (A) is
a structural unit (a1) represented by the following general formula (a1);
a structural unit (a2) represented by the following general formula (a2);
A negative photosensitive resin composition comprising:

(In the general formula (a1), Y is selected from groups represented by the following general formula (a1-1), the following general formula (a1-2) and the following general formula (a1-3), and a plurality of Y They may be the same or different.

(In general formula (a1-1), R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R ⁷ and a plurality of R ⁸ may be the same or different, R ⁹ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to ³ carbon atoms; may be the same or different, and * indicates a bond.
In general formula (a1-2), each of R ¹⁰ and R ¹¹ independently represents a hydrogen atom, an alkyl group having ¹ to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; , a plurality of R ¹¹ may be the same or different. * indicates a bond.
In general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group.
* indicates a bond. )
In general formula (a2), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R ¹ and R ² are different groups; R3 and ^R4 ^are different groups.
X ¹ represents a single bond, -SO ₂ -, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; , a plurality of X ¹ may be the same or different. )
[2] The negative photosensitive resin composition according to [1], wherein the polyimide (A) further contains a structural unit (a3) represented by the following general formula (a3).

(In general formula (a3), Q ¹ and Q ² each independently represent a hydroxyl group and a carboxyl group. X ² is a single bond, —SO ₂ —, —C(=O)—, having 1 to 5 linear or branched alkylene group, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and multiple X ² may be the same or different.)
[3] The negative photosensitive resin composition according to [1] or [2], wherein the polyimide (A) contains a structural unit represented by the following general formula (1).

(In general formula (1), R ¹ to R ⁴ and X ¹ have the same meanings as in general formula (a2), and Y has the same meaning as in general formula (a1).)
[4] The negative photosensitive resin composition according to [2] or [3], wherein the polyimide (A) contains a structural unit represented by the following general formula (2).

(In general formula (2), Q ¹ , Q ² and X ² are synonymous with general formula (a3), and Y is synonymous with general formula (a1).)
[5] a structural unit (a1) represented by the following general formula (a1);
a structural unit (a2) represented by the following general formula (a2);
A negative photosensitive polymer comprising:

(In general formula (a1-1), R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R ⁷ and a plurality of R ⁸ may be the same or different, R ⁹ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to ³ carbon atoms; may be the same or different, and * indicates a bond.
In general formula (a1-2), each of R ¹⁰ and R ¹¹ independently represents a hydrogen atom, an alkyl group having ¹ to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; , a plurality of R ¹¹ may be the same or different. * indicates a bond.
In general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group.
* indicates a bond. )
In general formula (a2), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R ¹ and R ² are different groups; R3 and ^R4 ^are different groups.
X ¹ represents a single bond, -SO ₂ -, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; , a plurality of X ¹ may be the same or different. )
[6] The negative photosensitive polymer according to [5], further comprising a structural unit (a3) represented by the following general formula (a3).

(In general formula (a3), Q ¹ and Q ² each independently represent a hydroxyl group and a carboxyl group. X ² is a single bond, —SO ₂ —, —C(=O)—, having 1 to 5 linear or branched alkylene group, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and multiple X ² may be the same or different.)
[7] The negative photosensitive polymer according to [5] or [6], which contains a structural unit represented by the following general formula (1).

(In general formula (1), R ¹ to R ⁴ and X ¹ have the same meanings as in general formula (a2), and Y has the same meaning as in general formula (a1).)
[8] The negative photosensitive polymer of [5] or [6], comprising a structural unit represented by the following general formula (2).

(In general formula (2), Q ¹ , Q ² and X ² are synonymous with general formula (a3), and Y is synonymous with general formula (a1).)
[9] The negative photosensitive polymer according to any one of [6] to [8], which has a weight-average molecular weight reduction rate of 9% or less as measured under the following conditions.
(conditions)
400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water are added to 100 parts by mass of the negative photosensitive polymer, and the mixture is stirred at 100°C for 6 hours. .
Formula: [(weight average molecular weight before test - weight average molecular weight after test) / weight average molecular weight before test] × 100
[10] A cured film comprising a cured product of the negative photosensitive resin composition according to any one of [1] to [4].
[11] A semiconductor device comprising a resin film containing a cured product of the negative photosensitive resin composition according to any one of [1] to [4].
[12] an interlayer insulating film;
a resin film containing a cured product of the negative photosensitive resin composition according to any one of [1] to [4] provided on the interlayer insulating film;
a rewiring embedded in the resin film;
A semiconductor device comprising:

According to the present invention, a negative photosensitive polymer which is excellent in solubility in an organic solvent, inhibits hydrolysis, and provides a cured product such as a film having excellent mechanical strength such as elongation, and the polymer. A negative photosensitive resin composition can be provided.

1 is a schematic cross-sectional view of a semiconductor device according to an embodiment; FIG.

Embodiments of the present invention will be described below with reference to the drawings. In addition, in all the drawings, the same constituent elements are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. In addition, "A to B" represents "above A" to "below B" unless otherwise specified.

The negative photosensitive resin composition of this embodiment contains (A) a polyimide, (B) a cross-linking agent containing a polyfunctional (meth)acrylate, and (C) a photopolymerization initiator.

[Polyimide (A)]
The polyimide (A) (negative photosensitive polymer) of the present embodiment includes a structural unit (a1) represented by the following general formula (a1), and a structural unit (a2) represented by the following general formula (a2). including.

In general formula (a1), Y is a divalent organic group.
As the divalent organic group, a known organic group can be used as long as the effects of the present invention are exhibited. 2) and a divalent organic group selected from general formula (a1-3) below.

In general formula (a1-1), R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and multiple R ⁷ , multiple R ⁸ may be the same or different.
From the viewpoint of the effects of the present invention, R ⁷ and R ⁸ are preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom.

R ⁹ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R ⁹ may be the same or different.
From the viewpoint of the effects of the present invention, R ⁹ is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom.
* indicates a bond.

In general formula (a1-2), each of R ¹⁰ and R ¹¹ independently represents a hydrogen atom, an alkyl group having ¹ to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; , a plurality of R ¹¹ may be the same or different.

From the viewpoint of the effect of the present invention, R ¹⁰ and R ¹¹ are preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably at least one of R ¹⁰ and at least one of R ¹¹ an alkyl group having 1 to 3 carbon atoms, more preferably three R ¹⁰ are alkyl groups having 1 to 3 carbon atoms, one R ¹⁰ is a hydrogen atom, and three R ¹¹ are alkyl groups having 1 to 3 carbon atoms one R ¹¹ is a hydrogen atom, particularly preferably three R ¹⁰ are methyl groups and one R ¹⁰ is a hydrogen atom, and three R ¹¹ are methyl groups and one R ¹¹ is It is a hydrogen atom.
* indicates a bond.

In general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group.
* indicates a bond.

In general formula (a2), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R ¹ and R ² are different groups; R3 and ^R4 ^are different groups.
From the viewpoint of the effects of the present invention, R ¹ to R ⁴ are preferably alkyl groups having 1 to 3 carbon atoms.

X ¹ represents a single bond, -SO ₂ -, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; , a plurality of X ¹ may be the same or different.

X ¹ is preferably a single bond, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and more A linear or branched alkylene group having 1 to 5 carbon atoms or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms is preferred.

By containing the structural unit represented by the general formula (a2), the polyimide (A) of the present embodiment suppresses the influence of the imide ring on the electrons, suppresses the hydrolysis of the polyimide, and improves mechanical properties such as elongation. Excellent strength and excellent solubility in organic solvents. In other words, the polyimide (A) of the present embodiment and the negative photosensitive resin composition containing the polyimide (A) have an excellent balance of these properties.

The polyimide (A) can further contain a structural unit (a3) represented by the following general formula (a3). Inclusion of the structural unit (a3) further improves solvent solubility.

In general formula (a3), Q ¹ and Q ² each independently represent a hydroxyl group or a carboxyl group, preferably a hydroxyl group.

X ² represents a single bond, -SO ₂ -, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; , multiple X ² may be the same or different.

From the viewpoint of the effects of the present invention, X ² is preferably a linear or branched alkylene group having 1 to 5 carbon atoms or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms.

Specifically, the polyimide (A) of the present embodiment can contain a structural unit represented by the following general formula (1).

In general formula (1), R ¹ to R ⁴ and X ¹ have the same meanings as in general formula (a2), and Y has the same meaning as in general formula (a1).

Specifically, the polyimide (A) of the present embodiment may further contain a structural unit represented by the following general formula (2).

In general formula (2), Q ¹ , Q ² and X ² have the same meanings as in general formula (a3), and Y has the same meaning as in general formula (a1).

At least one of both ends of the polyimide (A) of the present embodiment is preferably a group represented by the following general formula (3). By containing the group, hydrolysis is suppressed and mechanical strength such as elongation is improved.

In general formula (3), Y is synonymous with general formula (a1). * indicates a bond.

The weight average molecular weight of the polyimide (A) of this embodiment is 5,000 to 200,000, preferably 10,000 to 100,000.

In addition, since the polyimide (A) of the present embodiment has excellent solubility in solvents and does not need to be varnished in a precursor state, a varnish containing the polyimide (A) can be prepared. A cured product such as a film can be obtained from the varnish.

<Method for producing polyimide (A)>
A method for producing a polyimide (A) (negative photosensitive polymer) having a structural unit represented by the general formula (1) of the present embodiment,
An acid anhydride (a1′) represented by the following general formula (a1′) and a diamine (a2′) represented by the following general formula (a2′) are subjected to imide at a temperature of 100° C. or higher and 250° C. or lower. and converting.
According to this embodiment, a polyimide (A) having excellent solubility in organic solvents can be synthesized by a simple method.

In general formula (a1'), Y is selected from groups represented by general formula (a1-1), (a1-2) or (a1-3).

In general formula (a2'), R ¹ to R ⁴ and X ¹ have the same meanings as in general formula (a2).

The equivalent ratio of the acid anhydride (a1') and the diamine (a2') in the imidization reaction in this step is an important factor that determines the molecular weight of the resulting polyimide. In general, it is well known that there is a correlation between the molecular weight and mechanical properties of polymers, the higher the molecular weight the better the mechanical properties. Therefore, in order to obtain a polyimide having practically excellent strength, it is necessary to have a certain degree of high molecular weight. In the present invention, the equivalent ratio of the acid anhydride (a1′) and the diamine (a2′) to be used is not particularly limited, but the equivalent ratio of the acid anhydride (a1′) to the diamine (a2′) is 0.85 to It is preferably in the range of 1.15. If it is less than 0.85, the molecular weight is so low that it becomes brittle, resulting in weak mechanical strength. On the other hand, when it exceeds 1.15, the molecular weight is low and the material becomes brittle, resulting in a weak mechanical strength. That is, when the equivalent ratio is within the above range, excellent mechanical strength and excellent production stability are achieved.

Through this step, preferably, a polyimide (A) in which at least one of both terminals is an acid anhydride group represented by the following general formula (3) can be obtained. By including the acid anhydride group, the mechanical strength such as elongation of the cured product can be further improved. Specifically, the acid anhydride group reacts with the epoxy group of the compound having an epoxy group. When it has two or more epoxy groups, the polyimides (A) can be crosslinked with the compound.

Furthermore, in this step, from the viewpoint of the effect of the present invention, a diamine (a3′) represented by the following general formula (a3′) is used, an acid anhydride (a1′), a diamine (a2′), It is also preferable to imidize the diamine (a3') at a temperature of 100°C or higher and 250°C or lower.

Thereby, a polyimide (A) (negative photosensitive polymer) having a structural unit represented by the general formula (2) together with the structural unit represented by the general formula (1) can be obtained.

In general formula (a3'), Q ¹ , Q ² and X ² are synonymous with general formula (a3).
In order to control the molecular weight of the resulting polyimide, it is also possible to add a small amount of acid anhydride or aromatic amine as an end-capping agent to react and form a group at the end that can react with the epoxy group to form a bond. is.

Acid anhydrides as end capping agents include phthalic anhydride, maleic anhydride, nadic anhydride, and trimellitic anhydride, and aromatic amines include p-methylaniline, p-methoxyaniline, p-phenoxy Aniline, 4-carboxyaniline and the like can be mentioned. The amount of acid anhydride or aromatic amine added as the end capping agent is preferably 5 mol % or less. If it exceeds 5 mol %, the molecular weight of the obtained polyimide (A) is significantly lowered, causing problems in heat resistance and mechanical properties.

The equivalent ratio of acid anhydride (a1'), diamine (a2') and diamine (a3') is an important factor that determines the molecular weight of the resulting polymer. In general, it is well known that there is a correlation between the molecular weight and mechanical properties of polymers, the higher the molecular weight the better the mechanical properties. Therefore, in order to obtain a polymer having practically excellent strength, it is necessary to have a high molecular weight to some extent. In the present invention, the equivalent ratio of the acid anhydride (a1′), the diamine (a2′) and the diamine (a3′) to be used is not particularly limited, but the diamine (a2′) and the diamine to the acid anhydride (a1′) The equivalent ratio with (a3′) is preferably in the range of 0.70 to 1.30. If the corresponding amount ratio is within the above range, the mechanical strength is excellent and the manufacturing stability is excellent.

This step (imidation reaction step) can be performed in an organic solvent by a known method.
Examples of organic solvents include aprotic polar solvents such as γ-butyl lactone (GBL), N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, cyclohexanone, and 1,4-dioxane. , and one type or two or more types may be used in combination. At this time, a nonpolar solvent compatible with the aprotic polar solvent may be mixed and used. Examples of nonpolar solvents include aromatic hydrocarbons such as toluene, ethylbenzene, xylene, mesitylene and solvent naphtha, and ether solvents such as cyclopentyl methyl ether. The ratio of the non-polar solvent in the mixed solvent is set arbitrarily according to the resin properties such as the stirring device capacity and solution viscosity, as long as the solubility of the solvent decreases and the polyamic acid resin obtained by the reaction does not precipitate. can do.

The reaction temperature is 0° C. or higher and 100° C. or lower, preferably 20° C. or higher and 80° C. or lower, for about 30 minutes to 2 hours. React for some time.

By the above production method, a reaction solution containing the polyimide (A) (negative photosensitive polymer) of the present embodiment can be obtained, and further diluted with an organic solvent or the like as necessary to form a polymer solution (coating varnish). can be used as As the organic solvent, those exemplified in the above step can be used, and the same organic solvent as that in the step may be used, or a different organic solvent may be used.

In addition, this reaction solution is put into a poor solvent to reprecipitate the polyimide (A) resin to remove unreacted monomers, and the dried and solidified product can be dissolved again in an organic solvent and used as a purified product. . Particularly in applications where impurities and foreign matters are a problem, it is preferable to redissolve the varnish in an organic solvent to obtain a filtration-purified varnish.

The polyimide (A) (negative photosensitive polymer) of the present embodiment has excellent hydrolysis resistance, and the weight average molecular weight reduction rate measured under the following conditions is 9% or less, preferably 8% or less. be.
(conditions)
400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water are added to 100 parts by mass of the negative photosensitive polymer, and the mixture is stirred at 100°C for 6 hours. .
Formula: [(weight average molecular weight before test - weight average molecular weight after test) / weight average molecular weight before test] × 100

The negative photosensitive polymer of the present embodiment has a reduction rate of the weight average molecular weight within the above range, so that hydrolysis is suppressed and a cured product such as a film having excellent mechanical strength such as elongation can be obtained. can.

Table A below shows preferred formulation examples of the negative photosensitive polymer of the present embodiment.

・MED-J: 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane ・BAFA: 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane ・BAPA: 2,2 -Bis(3-amino-4-hydroxyphenyl)propane/TMPBP-TME: 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl] -2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5-carboxylate BPZ-TME: 4-{[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy) Phenyl]cyclohexyl}phenyl 1,3-dioxoisobenzofuran-5-carboxylate TMHQ: p-phenylenebis(trimellitate anhydride)

[Crosslinking agent (B)]
In this embodiment, a polyfunctional (meth)acrylate can be included as the cross-linking agent (B). Here, a polyfunctional (meth)acrylate is a compound having two or more (meth)acryloyl groups.
In addition, in this embodiment, a (meth)acryloyl group indicates an acryloyl group or a methacryloyl group.

From the viewpoint of the effects of the present invention, the polyfunctional (meth)acrylate is preferably trifunctional or higher. Although there is no particular upper limit for the number of functional groups of the polyfunctional (meth)acrylate compound, the upper limit for the number of functional groups is, for example, 11 functional groups in consideration of the availability of raw materials.
As a general trend, when a polyfunctional (meth)acrylate compound having a large number of functional groups ((meth)acryloyl groups) is used, the chemical resistance of the cured film tends to increase. On the other hand, when a polyfunctional (meth)acrylate compound having a small number of functional groups ((meth)acryloyl groups) is used, mechanical properties such as tensile elongation of the cured film tend to be improved.

As an example, the polyfunctional (meth)acrylate compound preferably contains a (meth)acrylate compound (B1) having a functionality of 7 or more.

As an example, the polyfunctional (meth)acrylate compound preferably contains a 5- to 6-functional (meth)acrylate compound (B2).

As an example, the polyfunctional (meth)acrylate compound preferably contains a tri- to tetra-functional (meth)acrylate compound (B3).

As an example, the polyfunctional (meth)acrylate compound can include compounds represented by the following general formula. In the general formulas below, R' is a hydrogen atom or a methyl group, n is 0 to 3, and R is a hydrogen atom or a (meth)acryloyl group.

Specific examples of polyfunctional (meth)acrylate compounds include the following. Of course, polyfunctional (meth)acrylate compounds are not limited to these.

Ethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate , Polyol polyacrylates such as dipentaerythritol hexa (meth) acrylate, di (meth) acrylate of bisphenol A diglycidyl ether, epoxy acrylates such as di (meth) acrylate of hexanediol diglycidyl ether, polyisocyanate and urethane (meth)acrylates obtained by reaction of hydroxyl group-containing (meth)acrylates such as hydroxyethyl (meth)acrylate;

Aronix M-400, Aronix M-460, Aronix M-402, Aronix M-510, Aronix M-520 (manufactured by Toagosei Co., Ltd.), KAYARAD T-1420, KAYARAD DPHA, KAYARAD DPCA20, KAYARAD DPCA30, KAYARAD DPCA60, KAYARAD DPCA120 (manufactured by Nippon Kayaku Co., Ltd.), Viscoat #230, Viscoat #300, Viscoat #802, Viscoat #2500, Viscoat #1000, Viscoat #1080 (manufactured by Osaka Organic Chemical Industry Co., Ltd.), NK Ester A-BPE-10 , NK Ester A-GLY-9E, NK Ester A-9550, and NK Ester A-DPH (manufactured by Shin-Nakamura Chemical Co., Ltd.).

The photosensitive resin composition may contain only one polyfunctional (meth)acrylate compound, or may contain two or more polyfunctional (meth)acrylate compounds. In the latter case, it is preferable to use together polyfunctional (meth)acrylate compounds having different numbers of functional groups. By using polyfunctional (meth)acrylate compounds with different numbers of functional groups together, it is possible to create a more complex "intertwining structure of polyimide with a cyclic structure and polyfunctional (meth)acrylate", which results in better heat resistance and mechanical properties. It is considered to be obtained.
By the way, among commercially available polyfunctional (meth)acrylate compounds, there is also a mixture of (meth)acrylates having different numbers of functional groups.

The amount of the polyfunctional (meth)acrylate compound is, for example, 50 to 200 parts by weight, preferably 60 to 150 parts by weight, more preferably 70 to 120 parts by weight, based on 100 parts by weight of the polyimide (A).
The amount of polyfunctional (meth)acrylate compound used is not particularly limited, but by appropriately adjusting the amount used as described above, one or more of the various properties can be enhanced. As described above, in the photosensitive resin composition of the present embodiment, it is considered that "an entangled structure of a polyimide having a cyclic structure and a polyfunctional (meth)acrylate" is formed by curing, but the polyimide (A) By appropriately adjusting the amount of the polyfunctional (meth) acrylate compound used, the polyimide (A) and the polyfunctional (meth) acrylate compound are sufficiently entangled, and the excess components that do not participate in the entanglement are reduced, resulting in , the performance is expected to be even better.

In this embodiment, when at least one of both ends of the polyimide (A) is an acid anhydride group represented by the general formula (3), an epoxy resin can be included as the cross-linking agent (B). Thereby, the mechanical strength such as elongation of the cured product can be further improved.

As the epoxy resin, general compounds having two or more epoxy groups in one molecule can be appropriately used.
Specific examples of epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol M type epoxy resin (4,4' -(1,3-phenylenediisopridiene) bisphenol type epoxy resin), bisphenol P type epoxy resin (4,4'-(1,4-phenylenediisopridiene) bisphenol type epoxy resin), bisphenol Z type epoxy Bisphenol-type epoxy resins such as resins (4,4'-cyclohexidiene bisphenol-type epoxy resins) and tetramethylbisphenol F-type epoxy resins; Novolak type epoxy resins such as tetraphenol group ethane type novolak type epoxy resins and novolak type epoxy resins having a condensed ring aromatic hydrocarbon structure; biphenyl type epoxy resins; aralkyl type epoxy resins such as xylylene type epoxy resins and biphenylaralkyl type epoxy resins Resin: Having a naphthalene skeleton such as naphthylene ether type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, naphthalene diol type epoxy resin, bi- to tetrafunctional epoxy type naphthalene resin, binaphthyl type epoxy resin, naphthalene aralkyl type epoxy resin, etc. Epoxy resin; anthracene type epoxy resin; phenoxy type epoxy resin; dicyclopentadiene type epoxy resin; norbornene type epoxy resin; adamantane type epoxy resin; fluorene type epoxy resin, phosphorus-containing epoxy resin, alicyclic epoxy resin, aliphatic chain Heterocyclic epoxy resins such as epoxy resins, bisphenol A novolak-type epoxy resins, bixylenol-type epoxy resins, trihydroxyphenylmethane-type epoxy resins, stilbene-type epoxy resins, tetraphenylolethane-type epoxy resins, and triglycidyl isocyanurate; , N,N',N'-tetraglycidylmetaxylenediamine, N,N,N',N'-tetraglycidylbisaminomethylcyclohexane, N,N-diglycidylaniline and other glycidylamines, and glycidyl (meth) copolymers of acrylates and compounds having ethylenically unsaturated double bonds; epoxy resins having a butadiene structure; diglycidyl-etherified sphenol; diglycidyl-etherified naphthalenediol; glycidyl-etherified phenols;
Epoxy resins include n-butyl glycidyl ether, 2-ethoxyhexyl glycidyl ether, phenyl glycidyl ether, allyl glycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerol polyglycidyl ether. Ethers, glycidyl ethers such as sorbitol polyglycidyl ether, glycidyl ether of bisphenol A (or F), glycidyl esters such as diglycidyl adipate and diglycidyl o-phthalate, 3,4-epoxycyclohexylmethyl (3,4 -epoxycyclohexane) carboxylate, 3,4-epoxy-6-methylcyclohexylmethyl (3,4-epoxy-6-methylcyclohexylmethyl) carboxylate, bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate, di Cyclopentanediene oxide, bis(2,3-epoxycyclopentyl) ether, alicyclic epoxy resins such as Daicel Celoxide 2021P, Celoxide 2081, Celoxide 2083, Celoxide 2085, Celoxide 8000, and Epolead GT401, 2,2' -(((((1-(4-(2-(4-(oxiran-2-ylmethoxy)phenyl)propan-2-yl)phenyl)ethane-1,1-diyl)bis(4,1-phenylene) ) bis (oxy)) bis (methylene)) bis (oxirane)) (for example, Techmore VG3101L manufactured by Printec Co., Ltd.), Epolite 100MF (manufactured by Kyoeisha Chemical Industry Co., Ltd.), Fat such as Epiol TMP (manufactured by NOF Corporation) group polyglycidyl ether, 1,1,3,3,5,5-hexamethyl-1,5-bis(3-(oxiran-2-ylmethoxy)propyl)trisiloxane (for example, DMS-E09 (manufactured by Gelest) ) can also be mentioned.

As the epoxy resin, one having 2 to 4 epoxy groups in one molecule is preferable, and one having 2 to 3 epoxy groups in one molecule is more preferable. By adjusting the number of functional groups of the epoxy resin, it is easy to improve, for example, the heat resistance of the cured film and the mechanical properties of the cured film in a well-balanced manner.
From another point of view, the epoxy resin preferably has an aromatic ring structure and/or an alicyclic structure. The use of such an epoxy resin is particularly preferable from the viewpoint of heat resistance.

When using an epoxy resin, only one epoxy resin may be used, or two or more epoxy resins may be used in combination.
When an epoxy resin is used, its amount is, for example, 0.5 to 30 parts by weight, preferably 1 to 20 parts by weight, more preferably 3 to 15 parts by weight, based on 100 parts by weight of polyimide (A).

[Photoinitiator (C)]
As the photopolymerization initiator (C), for example, a photoradical generator can be used. Photoradical generators are particularly effective in polymerizing polyfunctional (meth)acrylate compounds.

The photoradical generator that can be used is not particularly limited, and known ones can be used as appropriate.
For example, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-( 2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl} -2-methylpropan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl) -butanone-1,2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone and other alkylphenone compounds; benzophenone, 4 , 4′-bis(dimethylamino)benzophenone, benzophenone compounds such as 2-carboxybenzophenone; benzoin compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether; thioxanthone, 2-ethylthioxanthone, 2 -thioxanthone compounds such as isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, and 2,4-diethylthioxanthone; 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine , 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-ethoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-( Halomethylated triazine compounds such as 4-ethoxycarbonylnaphthyl)-4,6-bis(trichloromethyl)-s-triazine; 2-trichloromethyl-5-(2'-benzofuryl)-1,3,4-oxa diazole, 2-trichloromethyl-5-[β-(2′-benzofuryl)vinyl]-1,3,4-oxadiazole, 4-oxadiazole, 2-trichloromethyl-5-furyl-1,3 Halomethylated oxadiazole compounds such as ,4-oxadiazole; 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2 ,2′-bis(2,4-dichlorophenyl)-4,4′,5,5′- Tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, etc. Biimidazole compounds; 1,2-octanedione, 1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime), ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)- 9H-carbazol-3-yl]-,1-(O-acetyloxime) and other oxime ester compounds; bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3 -(1H-pyrrol-1-yl)-phenyl) titanocene compounds such as titanium; benzoic acid ester compounds such as p-dimethylaminobenzoic acid and p-diethylaminobenzoic acid; acridine compounds such as 9-phenylacridine; etc. can be mentioned. Among these, oxime ester compounds can be preferably used.

The negative photosensitive resin composition of this embodiment may contain only 1 type of photoinitiator (C), and may contain 2 or more types.
The amount of the photopolymerization initiator (C) used is, for example, 1 to 30 parts by mass, preferably 5 to 20 parts by mass, per 100 parts by mass of the polyfunctional (meth)acrylate compound.

(Thermal radical initiator (D))
The negative photosensitive resin composition of the present embodiment preferably contains a thermal radical initiator (D). By using the thermal radical initiator (D), for example, the heat resistance of the cured film can be further enhanced and/or the chemical resistance (resistance to organic solvents and the like) of the cured film can be enhanced. This is probably because the use of the thermal radical initiator (D) further accelerates the polymerization reaction of the polyfunctional (meth)acrylate compound.

The thermal radical initiator (D) preferably contains an organic peroxide. Organic peroxides include octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, oxalic acid peroxide, 2,5-dimethyl- 2,5-di(2-ethylhexanoylperoxy)hexane, 1-cyclohexyl-1-methylethylperoxy 2-ethylhexanoate, t-hexylperoxy 2-ethylhexanoate, t-butylperoxy 2-ethylhexanoate, m-toluyl peroxide, benzoyl peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, acetyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, cumene hydroperoxide, dicyclo Examples include mill peroxide, t-butyl perbenzoate, parachlorobenzoyl peroxide, cyclohexanone peroxide, and the like.

When using the thermal radical initiator (D), only one thermal radical initiator (D) may be used, or two or more thermal radical initiators (D) may be used.
When the thermal radical initiator (D) is used, its amount is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of the polyfunctional (meth)acrylate compound.

(adherence aid)
The negative photosensitive resin composition according to this embodiment may further contain an adhesion aid.
A silane coupling agent can be preferably used as the adhesion aid. By using a silane coupling agent, for example, the adhesion between the substrate and the cured film can be further enhanced.

Silane coupling agents include, for example, amino group-containing silane coupling agents, epoxy group-containing silane coupling agents, (meth)acryloyl group-containing silane coupling agents, mercapto group-containing silane coupling agents, and vinyl group-containing silane coupling agents. A silane coupling agent such as a ureido group-containing silane coupling agent, a sulfide group-containing silane coupling agent, and a silane coupling agent having a cyclic anhydride structure can be used.

Examples of amino group-containing silane coupling agents include bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane. Silane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-amino Propylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane, N-phenyl-γ-amino-propyltrimethoxysilane and the like.
Examples of epoxy group-containing silane coupling agents include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and γ-glycidyl. propyltrimethoxysilane and the like.
Examples of (meth)acryloyl group-containing silane coupling agents include γ-((meth)acryloyloxypropyl)trimethoxysilane, γ-((meth)acryloyloxypropyl)methyldimethoxysilane, γ-((meth) acryloyloxypropyl)methyldiethoxysilane and the like.
Mercapto group-containing silane coupling agents include, for example, 3-mercaptopropyltrimethoxysilane.
Vinyl group-containing silane coupling agents include, for example, vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane and the like.
Ureido group-containing silane coupling agents include, for example, 3-ureidopropyltriethoxysilane.
Examples of sulfide group-containing silane coupling agents include bis(3-(triethoxysilyl)propyl)disulfide and bis(3-(triethoxysilyl)propyl)tetrasulfide.
Silane coupling agents having a cyclic anhydride structure include, for example, 3-trimethoxysilylpropylsuccinic anhydride, 3-triethoxysilylpropylsuccinic anhydride, and 3-dimethylmethoxysilylpropylsuccinic anhydride. be done.

In this embodiment, a silane coupling agent having a cyclic anhydride structure is particularly preferably used. Although the details are unknown, it is speculated that the cyclic anhydride structure readily reacts with the main chain, side chains and/or terminals of the polyimide (A), resulting in a particularly good effect of improving adhesion.

When a silane coupling agent is used, it may be used alone, or two or more adhesion aids may be used in combination.
When a silane coupling agent is used, the amount used is, for example, 0.1 to 20 parts by mass, preferably 0.3 to 15 parts by mass, more preferably 0.3 to 15 parts by mass, when the amount of polyimide (A) used is 100 parts by mass. 0.4 to 12 parts by mass, more preferably 0.5 to 10 parts by mass.

(Surfactant)
The photosensitive resin composition of this embodiment preferably contains a surfactant. This can further improve the applicability of the photosensitive resin composition and the flatness of the film.
Examples of surfactants include fluorine-based surfactants, silicone-based surfactants, alkyl-based surfactants, and acrylic surfactants.
From another point of view, the surfactant is preferably nonionic. The use of nonionic surfactants is preferable, for example, from the viewpoint of suppressing unintentional reactions with other components in the composition and enhancing the storage stability of the composition.

The surfactant preferably contains a surfactant containing at least one of a fluorine atom and a silicon atom. This contributes to obtaining a uniform resin film (improvement of coatability), improvement of developability, and improvement of adhesion strength. Such a surfactant is preferably, for example, a nonionic surfactant containing at least one of a fluorine atom and a silicon atom. Examples of commercial products that can be used as surfactants include F-251, F-253, F-281, F-430, F-477, F-551 of the "Megafac" series manufactured by DIC Corporation, F-552, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F- 565, F-568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, etc. Fluorine-containing oligomer structure surfactants, fluorine-containing nonionic surfactants such as Phthagent 250 and Phthagent 251 manufactured by Neos Co., Ltd., SILFOAM (registered trademark) series manufactured by Wacker Chemie (for example, SD 100 TS , SD 670, SD 850, SD 860, SD 882).
In addition, FC4430 and FC4432 manufactured by 3M are also preferable surfactants.

When the photosensitive resin composition of this embodiment contains a surfactant, it can contain one or more surfactants.
When the photosensitive resin composition of the present embodiment contains a surfactant, its amount is, for example, 0.001 to 1 part by mass, preferably 0.005, when the content of the polyimide (A) is 100 parts by mass. ~0.5 parts by mass.

(water)
The photosensitive resin composition of this embodiment may contain water. The presence of water, for example, facilitates the hydrolysis reaction of the silane coupling agent, and tends to further increase the adhesion between the substrate and the cured film.

When the photosensitive resin composition of the present embodiment contains water, the amount is preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the total solid content (non-volatile components) of the photosensitive resin composition. It is preferably 0.2 to 3 parts by mass, more preferably 0.5 to 2 parts by mass.

The water content of the photosensitive resin composition can be quantified by the Karl Fischer method.

(solvent)
The photosensitive resin composition of this embodiment preferably contains a solvent. Thereby, a photosensitive resin film can be easily formed on a substrate (particularly, a substrate having a step) by a coating method.
A solvent usually contains an organic solvent. The organic solvent is not particularly limited as long as it can dissolve or disperse each component described above and does not substantially chemically react with each component.

Examples of organic solvents include acetone, methyl ethyl ketone, toluene, propylene glycol methyl ethyl ether, propylene glycol dimethyl ether, propylene glycol 1-monomethyl ether 2-acetate, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, benzyl Alcohol, propylene carbonate, ethylene glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, dipropylene glycol methyl-n-propyl ether, butyl acetate, γ-butyrolactone, methyl lactate, ethyl lactate, butyl lactate and the like. . These may be used singly or in combination.

When the photosensitive resin composition of the present embodiment contains a solvent, the photosensitive resin composition of the present embodiment is usually in the form of varnish. More specifically, the photosensitive resin composition of the present embodiment is preferably a varnish-like composition in which at least polyimide (A) and a polyfunctional (meth)acrylate compound are dissolved in a solvent. Since the photosensitive resin composition of the present embodiment is in the form of varnish, it is possible to form a uniform film by coating. Moreover, since the polyimide (A) and the polyfunctional (meth)acrylate compound are "dissolved" in the solvent, a homogeneous cured film can be obtained.

When a solvent is used, it is used so that the concentration of the total solid content (nonvolatile components) in the photosensitive resin composition is preferably 10 to 50% by mass, more preferably 20 to 45% by mass. By setting it as this range, each component can fully be melt|dissolved or dispersed. In addition, good coatability can be ensured, which in turn leads to improvement in flatness during spin coating. Furthermore, the viscosity of the photosensitive resin composition can be appropriately controlled by adjusting the content of the non-volatile component.
From another point of view, the ratio of the polyimide (A) and the polyfunctional (meth)acrylate compound in the entire composition is preferably 20 to 50% by mass. By using a relatively large amount of polyimide (A) and polyfunctional (meth)acrylate compound, it is easy to form a film with an appropriate thickness.

(other ingredients)
In addition to the components described above, the photosensitive resin composition of the present embodiment may contain components other than the components listed above, if necessary. Examples of such components include antioxidants, fillers such as silica, sensitizers, film-forming agents, and the like.

(Preparation of negative photosensitive resin composition)
A method for preparing the negative photosensitive resin composition in the present embodiment is not limited, and a known method can be used depending on the components contained in the negative photosensitive resin composition.
For example, it can be prepared by mixing and dissolving the above components in a solvent.

(Negative photosensitive resin composition)
The negative photosensitive resin composition according to the present embodiment is formed by applying the negative photosensitive resin composition to a surface comprising a metal such as Al or Cu, and then pre-baking to dry it to form a resin film. Then, the resin film is patterned into a desired shape by exposure and development, and then the resin film is cured by heat treatment to form a cured film.

When the permanent film is produced, the pre-baking conditions may be, for example, heat treatment at a temperature of 90° C. or higher and 130° C. or lower for 30 seconds or longer and 1 hour or shorter. The heat treatment conditions are, for example, heat treatment at a temperature of 150° C. to 250° C. for 30 minutes to 10 hours, preferably about 170° C. for 1 to 6 hours.

The film obtained from the negative photosensitive resin composition of the present embodiment has a maximum elongation of 15 to 200%, preferably 20 to 150%, and an average elongation of 10 as measured by a tensile test using a Tensilon tester. ~150%, preferably 15-120%.

The film obtained from the negative photosensitive resin composition of the present embodiment preferably has a tensile strength of 20 MPa or more, more preferably 30 to 300 MPa, as measured by a tensile test using a Tensilon tester.

In addition, since the negative photosensitive resin composition of the present embodiment contains polyimide (A) (negative photosensitive polymer) having excellent hydrolysis resistance, it can be , Even after performing a HAST test (unsaturated pressurized steam test) for 96 hours, the rate of decrease in the elongation rate (maximum value, average value) represented by the following formula is 40% or less, preferably 35% or less, More preferably, it is 33% or less.
[(Elongation before test - Elongation after test) / Elongation before test)] × 100

The negative photosensitive resin composition of this embodiment is excellent in low-temperature curability.
For example, the cured product obtained by curing the negative photosensitive resin composition of the present embodiment at 170°C for 4 hours has a glass transition temperature (Tg) of 200°C or higher, preferably 210°C or higher, more preferably 220°C. °C or higher.

Furthermore, the cured product obtained by curing the negative photosensitive resin composition of the present embodiment at 170° C. for 4 hours has a storage elastic modulus E′ at 30° C. of 2.0 GPa or more, preferably 2.2 GPa or more, More preferably, it can be 2.5 GPa or more. Furthermore, the storage elastic modulus E' at 200°C can be 0.5 GPa or more, preferably 0.8 GPa or more, and more preferably 1.0 GPa or more.

The viscosity of the negative photosensitive resin composition according to this embodiment can be appropriately set according to the desired thickness of the resin film. The viscosity of the negative photosensitive resin composition can be adjusted by adding a solvent.

A cured product such as a film obtained from the negative photosensitive resin composition of the present embodiment has excellent chemical resistance.
Specifically, the film is immersed in a solution of less than 99% by mass of dimethyl sulfoxide and less than 2% by mass of tetramethylammonium hydroxide at 40° C. for 10 minutes, then thoroughly washed with isopropyl alcohol and air-dried. to measure. The film thickness change rate between the film thickness after treatment and the film thickness before treatment is calculated from the following formula and evaluated as the reduction rate of the film.
Formula: Film reduction rate (%) {(film thickness after immersion - film thickness before immersion) / film thickness before immersion x 100 (%)}

The film thickness change rate is preferably 40% or less, more preferably 30% or less. As a result, even when the cured film is subjected to a step of being immersed in dimethylsulfoxide, the film thickness hardly decreases. Therefore, a cured film that can maintain its functions even after being subjected to such steps can be obtained.

The negative photosensitive resin composition of the present embodiment has suppressed curing shrinkage, and is spin-coated on the surface of a silicon wafer so that the film thickness after drying becomes 10 μm, pre-baked at 120° C. for 3 minutes, and placed under a high-pressure mercury lamp. In the case where a film is prepared by exposing to 600 mJ / cm ² and then performing heat treatment at 170 ° C. for 120 minutes in a nitrogen atmosphere, the film thickness after the pre-bake is the film thickness A, and the film thickness after the heat treatment. is the film thickness B, and the cure shrinkage calculated from the following formula is preferably 12% or less, more preferably 10% or less.
Formula: Cure shrinkage rate [%] = {(film thickness A - film thickness B) / film thickness A} x 100

The negative photosensitive resin composition of the present embodiment has high heat resistance, and the resulting film has a weight loss temperature (Td5) measured by simultaneous thermogravimetric differential thermal measurement of 200° C. or higher, preferably 300° C. or higher. be able to.

The film made of the negative photosensitive resin composition of the present embodiment has suppressed shrinkage on curing, and can have a linear thermal expansion coefficient (CTE) of 200 ppm/°C or less, preferably 100 ppm/°C or less.

The film made of the negative photosensitive resin composition of the present embodiment has excellent mechanical strength, and has an elastic modulus at 25° C. of 1.0 to 5.0 GPa, preferably 1.5 to 3.0 GPa. can do.

(Application)
The negative photosensitive resin composition of the present embodiment is used for forming resin films for semiconductor devices such as permanent films and resists. Among these, from the viewpoint of expressing in a well-balanced manner the improvement in adhesion between the negative photosensitive resin composition and the Al pad after prebaking and the suppression of the generation of residues of the negative photosensitive resin composition during development, Use of a permanent film from the viewpoint of improving the adhesion between the cured film of the negative photosensitive resin composition and the metal, and also from the viewpoint of improving the chemical resistance of the negative photosensitive resin composition after heat treatment. It is preferably used for

In addition, in the present embodiment, the resin film includes a cured film of a negative photosensitive resin composition. That is, the resin film according to this embodiment is obtained by curing a negative photosensitive resin composition.

The permanent film is composed of a resin film obtained by pre-baking, exposing, and developing a negative photosensitive resin composition, patterning it into a desired shape, and then curing it by heat treatment. Permanent films can be used as protective films, interlayer films, dam materials, and the like for semiconductor devices.

The above-mentioned resist can be obtained, for example, by applying a negative photosensitive resin composition to an object to be masked by the resist by a method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, and negative photosensitive resin composition. It is composed of a resin film obtained by removing the solvent from a flexible resin composition.
An example of a semiconductor device according to this embodiment is shown in FIG.

The semiconductor device 100 according to this embodiment can be a semiconductor device including the resin film. Specifically, one or more of the group consisting of the passivation film 32, the insulating layer 42, and the insulating layer 44 in the semiconductor device 100 can be a resin film containing the cured product of the present embodiment. Here, the resin film is preferably the permanent film described above.

The semiconductor device 100 is, for example, a semiconductor chip. In this case, for example, a semiconductor package is obtained by mounting the semiconductor device 100 on the wiring substrate via the bumps 52 .

The semiconductor device 100 includes a semiconductor substrate provided with semiconductor elements such as transistors, and a multilayer wiring layer (not shown) provided on the semiconductor substrate. An interlayer insulating film 30 and a top layer wiring 34 provided on the interlayer insulating film 30 are provided in the uppermost layer of the multilayer wiring layers. The uppermost layer wiring 34 is made of aluminum Al, for example. A passivation film 32 is provided on the interlayer insulating film 30 and the uppermost layer wiring 34 . A portion of the passivation film 32 is provided with an opening through which the uppermost layer wiring 34 is exposed.

A rewiring layer 40 is provided on the passivation film 32 . The rewiring layer 40 includes an insulating layer 42 provided on the passivation film 32, a rewiring 46 provided on the insulating layer 42, an insulating layer 44 provided on the insulating layer 42 and the rewiring 46, have An opening connected to the uppermost layer wiring 34 is formed in the insulating layer 42 . The rewiring 46 is formed on the insulating layer 42 and in openings provided in the insulating layer 42 and connected to the uppermost layer wiring 34 . The insulating layer 44 is provided with an opening connected to the rewiring 46 .

A bump 52 is formed in the opening provided in the insulating layer 44 via a UBM (Under Bump Metallurgy) layer 50, for example. Semiconductor device 100 is connected to a wiring substrate or the like via bumps 52, for example.
Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be employed within the scope that does not impair the effects of the present invention.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these.
The following compounds were used in the examples.

4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane (hereinafter also referred to as MED-J) represented by the following formula

4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (hereinafter also referred to as TFMB) represented by the following formula

2,2-bis(3-amino-4-hydroxyphenyl)propane (hereinafter also referred to as BAPA) represented by the following formula

2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (hereinafter also referred to as BAFA) represented by the following formula

4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl 1,3 represented by the following formula -dioxoisobenzofuran-5-carboxylate (hereinafter also referred to as TMPBP-TME)

3,3′,4,4′-benzophenonetetracarboxylic dianhydride (hereinafter also referred to as BTDA) represented by the following formula

[Example 1]
First, 10.83 g (38.3 mmol) of MED-J and 25.77 g (41.7 mmol) of TMPBP-TME were placed in an appropriately sized reaction vessel equipped with a stirrer and condenser. An additional 109.80 g of GBL was then added to the reaction vessel.
After bubbling nitrogen for 10 minutes, the temperature was raised to 60° C. while stirring, and the reaction was allowed to proceed for 1.5 hours. After that, the mixture was further reacted at 180° C. for 3 hours to polymerize the diamine and the acid anhydride to prepare a polymerization solution.
The resulting reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to methanol to precipitate a white solid. The obtained white solid was collected and vacuum-dried at a temperature of 80° C. to obtain 31.17 g of a polymer.
GPC measurement of the polymer revealed a weight average molecular weight Mw of 55,900 and a polydispersity (weight average molecular weight Mw/number average molecular weight Mn) of 2.64.
The obtained polymer partially contained repeating units represented by the following formula.

[Example 2]
First, 3.87 g (13.7 mmol) MED-J, 5.02 g (13.7 mmol) BAFA, and 20.17 g (32 .6 mmol) was added. An additional 87.17 g of GBL was then added to the reaction vessel.
After bubbling nitrogen for 10 minutes, the temperature was raised to 60° C. while stirring, and the reaction was allowed to proceed for 1.5 hours. After that, the mixture was further reacted at 180° C. for 3 hours to polymerize the diamine, bisaminophenol and acid anhydride to prepare a polymerization solution.
The resulting reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to methanol to precipitate a white solid. The resulting white solid was collected and vacuum dried at a temperature of 80° C. to obtain 24.70 g of polymer.
GPC measurement of the polymer revealed a weight average molecular weight Mw of 18,500 and a polydispersity (weight average molecular weight Mw/number average molecular weight Mn) of 1.81.
The obtained polymer partially contained repeating units represented by the following formula.

[Example 3]
First, 3.87 g (13.7 mmol) MED-J, 3.54 g (13.7 mmol) BAPA, and 20.17 g (32 .6 mmol) was added. An additional 82.73 g of GBL was then added to the reaction vessel.
After bubbling nitrogen for 10 minutes, the temperature was raised to 60° C. while stirring, and the reaction was allowed to proceed for 1.5 hours. After that, the mixture was further reacted at 180° C. for 3 hours to polymerize the diamine, bisaminophenol and acid anhydride to prepare a polymerization solution.
The resulting reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to methanol to precipitate a white solid. The obtained white solid was collected and vacuum-dried at a temperature of 80° C. to obtain 23.13 g of polymer.
GPC measurement of the polymer revealed a weight average molecular weight Mw of 20,900 and a polydispersity (weight average molecular weight Mw/number average molecular weight Mn) of 1.92.
The obtained polymer partially contained repeating units represented by the following formula.

[Comparative Examples 1 to 3]
Comparative Examples 1 to 3 were synthesized in the same manner as in Example 2 except for the conditions described in Table 1.
In Comparative Examples 1 and 2, gelation occurred during the polymerization reaction, making it difficult to continue the reaction.

[Comparative Example 4]
First, 12.55 g (44.4 mmol) of MED-J and 17.90 g (55.6 mmol) of BTDA were placed in an appropriately sized reaction vessel equipped with a stirrer and condenser. An additional 91.36 g of GBL was then added to the reaction vessel.
After bubbling nitrogen for 10 minutes, the temperature was raised to 60° C. while stirring, and the reaction was allowed to proceed for 1.5 hours. After that, the mixture was further reacted at 180° C. for 3 hours to polymerize the diamine and the acid anhydride to prepare a polymerization solution.
The resulting reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to methanol to precipitate a white solid. The obtained white solid was collected and dried in vacuum at a temperature of 60° C. to obtain 23.77 g of polymer.
GPC measurement of the polymer revealed a weight average molecular weight Mw of 8,900 and a polydispersity (weight average molecular weight Mw/number average molecular weight Mn) of 1.69.

[Comparative Example 5]
First, 13.53 g (47.9 mmol) of MED-J and 16.78 g (52.1 mmol) of BTDA were placed in an appropriately sized reaction vessel equipped with a stirrer and condenser. An additional 90.95 g of GBL was then added to the reaction vessel.
After bubbling nitrogen for 10 minutes, the temperature was raised to 60° C. while stirring, and the reaction was allowed to proceed for 1.5 hours. After that, the mixture was further reacted at 180° C. for 3 hours to polymerize the diamine and the acid anhydride to prepare a polymerization solution.
The resulting reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to methanol to precipitate a white solid. The resulting white solid was collected and vacuum dried at 60° C. to obtain 26.16 g of polymer.
GPC measurement of the polymer revealed a weight average molecular weight Mw of 28,400 and a polydispersity (weight average molecular weight Mw/number average molecular weight Mn) of 1.95.

[Solubility in organic solvents]
The solubility of the negative photosensitive polymers obtained in Examples 1-3 and Comparative Examples 3-5 in γ-butyl lactone (GBL) was evaluated according to the following criteria. Table 1 shows the results.
(Evaluation criteria for solubility)
○: 5% by mass or more of polymer dissolved △: 1 to 5% by mass of polymer dissolved ×: Less than 1% by mass of polymer dissolved

[Hydrolysis resistance]
The rate of decrease in the weight average molecular weight of the negative photosensitive polymers obtained in Examples and Comparative Examples was measured under the following conditions. Table 1 shows the results.
(Conditions (no addition of triethylamine))
400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water were added to 100 parts by mass of the negative photosensitive polymer, and the mixture was stirred at 100°C for 6 hours.
Formula: [(weight average molecular weight before test - weight average molecular weight after test) / weight average molecular weight before test] × 100
(Conditions (addition of triethylamine))
10 parts by mass of triethylamine, 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water were added to 100 parts by mass of the negative photosensitive polymer, and the mixture was stirred at 100°C for 6 hours. Calculated by the formula.
Formula: [(weight average molecular weight before test - weight average molecular weight after test) / weight average molecular weight before test] × 100

[Polymer stability]
A composition containing the GBL solution of the polymer obtained in Example 1 and Comparative Example 5 (100 parts by mass of the polymer), the adhesion aid KBM-503P (2 parts by mass), and the surfactant FC4432 (0.1 part by mass) When a product was prepared and stored at room temperature for one day, only the composition of Comparative Example 5 increased in viscosity and gelled, so that elongation and the like could not be evaluated.

As shown in Table 1, the negative-working photosensitive polymers of the present invention obtained in Examples have excellent solubility in organic solvents, and since hydrolysis is suppressed, there is little reduction in elongation and mechanical strength. It was inferred that the decrease in

The following compounds were used in the preparation of the negative photosensitive resin composition.
(crosslinking agent)
Acrylate compound 1: dipentaerythritol hexaacrylate (NK Ester A-DPH, manufactured by Shin-Nakamura Chemical Co., Ltd.)
Epoxy compound 1: an epoxy compound represented by the following chemical formula (manufactured by Printec, VG3101L)

(Additive)
・ Additive 1: a phenol compound represented by the following formula (TrisP-PA, manufactured by Honshu Chemical Industry Co., Ltd.)

(Polymerization initiator)
- Photoradical generator: oxime ester photoradical generator (ADEKA, NCI-730)
・ Thermal radical generator: Dicumyl peroxide (Perkadox BC, peroxide, manufactured by Kayaku Akzo Co., Ltd.)

(adherence aid)
Adhesion aid 1: 3-methacryloxypropyltrimethoxysilane (KBM-503P, manufactured by Shin-Etsu Chemical Co., Ltd.)
Adhesion aid 2: 3-trimethoxysilylpropyl succinic anhydride (X-12-967C, manufactured by Shin-Etsu Chemical Co., Ltd.)

(Surfactant)
・Surfactant 1: Surfactant having a fluorocarbon chain (FC-4432, manufactured by Sumitomo 3M)

(solvent)
・Solvent 1: water ・Solvent 2: γ-butyl lactone (GBL)

[Example 4]
(Preparation of negative photosensitive resin composition)
A photosensitive resin composition was prepared by mixing the polymer of Example 1 (100 parts by mass of polymer) and the components shown in Table 2 in advance so as to form a 26.5 wt % GBL solution.
The obtained negative photosensitive resin composition was spin-coated on the surface of a silicon wafer so that the film thickness after drying was 10 μm, prebaked at 120° C. for 3 minutes, and then exposed to light at 600 mJ/cm ² with a high-pressure mercury lamp. After that, heat treatment was performed at 170° C. for 120 minutes in a nitrogen atmosphere to prepare a film.
The obtained film was measured for elongation by the following method to evaluate the patterning properties. Table 2 shows the results.

[Growth rate]
A test piece (6.5 mm×60 mm×10 μm thick) cut out from the film obtained in Example 4 was subjected to a tensile test (stretching speed: 5 mm/min) in an atmosphere of 23° C. The tensile test was performed using a tensile tester (Tensilon RTC-1210A) manufactured by Orientec. Five test pieces were measured, the tensile elongation was calculated from the breaking distance and the initial distance, and the average and maximum values of the elongation were obtained.
Furthermore, the test piece cut out from the film obtained in Example 4 was subjected to HAST (unsaturated pressurized steam test) for 96 hours under conditions of a temperature of 130 ° C. and a relative humidity of 85% RH. Similarly, the average value and maximum value of the elongation rate were obtained.

[Evaluation of patterning characteristics]
It was confirmed as follows that the photosensitive resin composition of Example 4 could be sufficiently patterned by exposure and development.
The photosensitive resin composition of Example 4 was applied onto an 8-inch silicon wafer using a spin coater. After the application, it was pre-baked on a hot plate at 110° C. for 3 minutes in the atmosphere to obtain a coating film having a thickness of about 5.0 μm.
This coating film was irradiated with an i-line through a mask having a via pattern with a width of 20 μm. An i-line stepper (NSR-4425i manufactured by Nikon Corporation) was used for irradiation.
After the exposure, spray development was carried out using cyclopentanone as a developer for 30 seconds, and further spray development was carried out using PGMEA as a developer for 10 seconds to dissolve and remove the unexposed areas to obtain a via pattern.
A cross section of the obtained via pattern was observed using a desktop SEM. The width at the middle height between the bottom surface of the via pattern and the opening was defined as the via width, and evaluation was made according to the following criteria.
Good patterning property: 20 μm via pattern opens Poor patterning property: 20 μm via pattern does not open The coating film obtained from the photosensitive resin composition of Example 4 had good patterning property.

As shown in Table 2, the film obtained from the negative photosensitive resin composition containing the negative photosensitive polymer of the present invention has excellent elongation and excellent hydrolysis resistance. Since it contains a polymer, it has become clear that the mechanical strength is excellent even after the HAST test. Moreover, it was confirmed that the patterning property was also favorable and it was suitably used as a negative photosensitive resin composition.

This application claims priority based on Japanese Patent Application No. 2021-105686 filed on June 25, 2021, and the entire disclosure thereof is incorporated herein.

100 semiconductor device 30 interlayer insulating film 32 passivation film 34 top layer wiring 40 rewiring layer 42 insulating layer 44 insulating layer 46 rewiring 50 UBM layer 52 bump

Claims

(A) polyimide;
(B) a cross-linking agent comprising a polyfunctional (meth)acrylate;
(C) a photoinitiator;
including
Polyimide (A) is
a structural unit (a1) represented by the following general formula (a1);
a structural unit (a2) represented by the following general formula (a2);
A negative photosensitive resin composition comprising:

(In the general formula (a1), Y is selected from groups represented by the following general formula (a1-1), the following general formula (a1-2) and the following general formula (a1-3), and a plurality of Y They may be the same or different.

(In general formula (a1-1), R 7 and R 8 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R 7 and a plurality of R 8 may be the same or different, R 9 represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; may be the same or different, and * indicates a bond.
In general formula (a1-2), each of R 10 and R 11 independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; , a plurality of R 11 may be the same or different. * indicates a bond.
In general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group.
* indicates a bond. )
In general formula (a2), R 1 to R 4 each independently represent an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R 1 and R 2 are different groups; R3 and R4 are different groups.
X 1 represents a single bond, -SO 2 -, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; , a plurality of X 1 may be the same or different. )
The negative photosensitive resin composition according to claim 1, wherein the polyimide (A) further contains a structural unit (a3) represented by the following general formula (a3).

(In general formula (a3), Q 1 and Q 2 each independently represent a hydroxyl group and a carboxyl group. X 2 is a single bond, —SO 2 —, —C(=O)—, having 1 to 5 linear or branched alkylene group, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and multiple X 2 may be the same or different.)
The negative photosensitive resin composition according to claim 1 or 2, wherein the polyimide (A) contains a structural unit represented by the following general formula (1).

(In general formula (1), R 1 to R 4 and X 1 have the same meanings as in general formula (a2), and Y has the same meaning as in general formula (a1).)
The negative photosensitive resin composition according to claim 2, wherein the polyimide (A) contains a structural unit represented by the following general formula (2).

(In general formula (2), Q 1 , Q 2 and X 2 are synonymous with general formula (a3), and Y is synonymous with general formula (a1).)
a structural unit (a1) represented by the following general formula (a1);
a structural unit (a2) represented by the following general formula (a2);
A negative photosensitive polymer comprising:

(In the general formula (a1), Y is selected from groups represented by the following general formula (a1-1), the following general formula (a1-2) and the following general formula (a1-3), and a plurality of Y They may be the same or different.

(In general formula (a1-1), R 7 and R 8 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R 7 and a plurality of R 8 may be the same or different, R 9 represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; may be the same or different, and * indicates a bond.
In general formula (a1-2), each of R 10 and R 11 independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms; , a plurality of R 11 may be the same or different. * indicates a bond.
In general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group.
* indicates a bond. )
In general formula (a2), R 1 to R 4 each independently represent an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R 1 and R 2 are different groups; R3 and R4 are different groups.
X 1 represents a single bond, -SO 2 -, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; , a plurality of X 1 may be the same or different. )
6. The negative photosensitive polymer according to claim 5, further comprising a structural unit (a3) represented by the following general formula (a3).

(In general formula (a3), Q 1 and Q 2 each independently represent a hydroxyl group and a carboxyl group. X 2 is a single bond, —SO 2 —, —C(=O)—, having 1 to 5 linear or branched alkylene group, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and multiple X 2 may be the same or different.)
7. The negative photosensitive polymer according to claim 5 or 6, comprising a structural unit represented by the following general formula (1).

(In general formula (1), R 1 to R 4 and X 1 have the same meanings as in general formula (a2), and Y has the same meaning as in general formula (a1).)
7. The negative photosensitive polymer according to claim 5 or 6, comprising a structural unit represented by the following general formula (2).

(In general formula (2), Q 1 , Q 2 and X 2 are synonymous with general formula (a3), and Y is synonymous with general formula (a1).)
7. The negative photosensitive polymer according to claim 6, wherein the weight average molecular weight reduction rate measured under the following conditions is 9% or less.
(conditions)
400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water are added to 100 parts by mass of the negative photosensitive polymer, and the mixture is stirred at 100°C for 6 hours. .
Formula: [(weight average molecular weight before test - weight average molecular weight after test) / weight average molecular weight before test] × 100
A cured film comprising a cured product of the negative photosensitive resin composition according to claim 1 or 2.
A semiconductor device comprising a resin film containing a cured product of the negative photosensitive resin composition according to claim 1 or 2.
an interlayer insulating film;
A resin film containing a cured product of the negative photosensitive resin composition according to claim 1 or 2, provided on the interlayer insulating film;
a rewiring embedded in the resin film;
A semiconductor device comprising: