JP6769139B2 - Polymers, photosensitive resin compositions and electronic devices - Google Patents

Description

The present invention relates to polymers, photosensitive resin compositions and electronic devices.

So far, the development of highly sensitive photosensitive resin compositions has been carried out. As a technique of this kind, there is a technique described in Patent Document 1. According to the same document, it is described that the use of a low molecular weight phenolic compound improves the solubility in an alkaline developer and improves the sensitivity (claim 1, paragraph 0056, paragraph 0145 of Patent Document 1). , Table 2).

Japanese Unexamined Patent Publication No. 2013-134346

However, as a result of examination by the present inventor, it has been found that the photosensitive resin composition described in the above document has room for improvement in terms of thermal flow resistance.

As a result of conducting various experiments, the present inventor has found that when a phenolic compound which is a low molecular weight monomer as described in the above document is used, the pattern shape is deformed (thermal flow) in the thermosetting process at a high temperature. The resistance may be reduced, and there may be a trade-off relationship between the increased sensitivity and the thermal flow resistance.
As a result of diligent examination focusing on such trade-off relationships,
(1) Utilization of polymer structure (2) In combination with a structural unit having an oxetanyl group and a structural unit derived from N-substituted maleimide having a hydroxy group or a carboxy group in the structure of the polymer,
As described above, it has been found that the thermal flow resistance is improved while the sensitivity is improved, and the present invention has been completed.

According to the present invention
A structural unit having an oxetanyl group and
Structural units derived from N-substituted maleimides having a hydroxy or carboxy group,
Only including,
The structural unit having an oxetanyl group is represented by the following general formula.
(In the above general formula, n is 0, 1 or 2. R ₁ , R ₂ , R ₃ and R ₄ are each independently hydrogen or an organic group having 1 to 10 carbon atoms, and at least of these. One has an oxetane group.)
A polymer in which the structural unit derived from the N-substituted maleimide is represented by the following general formula is provided.
(In the above general formula, X is an alkyl group having 1 to 15 carbon atoms and 6 to 14 carbon atoms substituted with one or more selected from the group consisting of a hydroxy group, a hydroxyalkyl group, a carboxy group and a carboxyalkyl group. Or a cycloalkyl group having 3 to 12 carbon atoms.)

Further, according to the present invention, a photosensitive resin composition containing the above polymer is provided.

Further, according to the present invention, there is provided an electronic device including a cured product of a photosensitive resin film made of the above-mentioned photosensitive resin composition.

According to the present invention, a polymer capable of achieving both high sensitivity and thermal flow resistance, a photosensitive resin composition using the polymer, and an electronic device are provided.

It is sectional drawing which shows an example of the electronic apparatus which concerns on this embodiment. It is a cross-sectional photograph of the hole pattern of Example 2 and Comparative Example 1.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are designated by the same reference numerals, and description thereof will be omitted as appropriate.

[polymer]
The outline of the polymer of this embodiment will be described.
The polymer of the present embodiment can contain a structural unit having an oxetanyl group and a structural unit derived from N-substituted maleimide having a hydroxy group or a carboxy group.

As described above, the present inventor has focused on the trade-off relationship between high sensitivity and thermal flow resistance, and as a result of repeated studies, without using a ballast material (phenolic compound of low molecular weight monomer), By utilizing the polymer structure and by using a structural unit having an oxetanyl group and a structural unit derived from N-substituted maleimide having a hydroxy group or a carboxy group in combination in the structure of the polymer, the sensitivity is improved. , The present invention has been completed by finding that the thermal flow resistance is improved.

According to this embodiment, it is possible to realize a polymer having both high sensitivity and thermal flow resistance, and a photosensitive resin composition using the polymer.

Furthermore, the present inventor has found that the stability over time is improved by using a structural unit having an oxetanyl group instead of a structural unit having an epoxy group in the structure of the polymer.

According to the present embodiment, it is possible to realize a polymer having an excellent balance of stability over time, high sensitivity and thermal flow resistance, and a photosensitive resin film made of the polymer.

The polymer of the present embodiment can be used as a polymer for forming a photosensitive resin film used for forming a photosensitive resin film made of a photosensitive resin composition. By using the polymer of the present embodiment, it is possible to realize a photosensitive resin composition or a photosensitive resin film having an excellent balance of high sensitivity, thermal flow resistance, and stability over time.

The details of the polymer of this embodiment will be described below.
The polymer of the present embodiment can contain a structural unit having an oxetanyl group and a structural unit derived from N-substituted maleimide having a hydroxy group and / and a carboxy group. In addition, the polymer of the present embodiment can contain a structural unit having an oxetanyl group and a structural unit derived from N-substituted maleimide having a hydroxy group.

In the present embodiment, the structural unit having an oxetanyl group may have, for example, a structure derived from norbornene.

The structural unit having an oxetanyl group having a structure derived from norbornene may be represented by, for example, the following general formula. These may be used alone or in combination of two or more.

In the above general formula, n is 0, 1 or 2. R ₁ , R ₂ , R ₃ and R ₄ are each independently hydrogen or an organic group having 1 to 10 carbon atoms, and at least one of them has an oxetane group.

Further, in the above formula, examples of the organic group having 1 to 10 carbon atoms constituting R ₁ , R ₂ , R ₃ and R ₄ include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group and an aralkyl group. Examples thereof include a hydrocarbon group having 1 to 10 carbon atoms such as an alkaline group or a cycloalkyl group, or an organic group having 1 to 10 carbon atoms containing an oxetane group, a carboxyl group or a glycidyl group. The organic group has at least one or more oxetane groups. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group and heptyl group. Examples include octyl group, nonyl group, and decyl group. Examples of the alkenyl group include an allyl group, a pentenyl group, and a vinyl group. Examples of the alkynyl group include an ethynyl group. Examples of the alkylidene group include a methylidene group and an ethylidene group. Examples of the aryl group include a phenyl group and a naphthyl group. Examples of the aralkyl group include a benzyl group and a phenethyl group. Examples of the alkaline group include a tolyl group and a xylyl group. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. In addition, in these alkyl group, alkenyl group, alkynyl group, alkylidene group, aryl group, aralkyl group, alkalil group, and cycloalkyl group, one or more hydrogen atoms are composed of halogen atoms such as fluorine, chlorine, bromine or iodine. It may be replaced.

The polymer of the present embodiment may further have a structural unit derived from norbornene having a carboxyl group or a glycidyl group in place of the oxetane group in the structure represented by the above general formula.

Further, in a structural unit having a carboxyl group having a structure derived from norbornene, as an organic group having 1 to 10 carbon atoms containing a carboxyl group, which constitutes R ₁ , R ₂ , R ₃ and R ₄ in the above general formula. For example, an organic group represented by the following formula (8) can be mentioned.

In the above formula (8), Z is a single bond or a divalent organic group having 1 to 9 carbon atoms. The divalent organic group constituting Z is a linear or branched divalent hydrocarbon group which may have any one or more of oxygen, nitrogen and silicon. In this embodiment, Z can be, for example, a single bond or an alkylene group having 1 to 7 carbon atoms. In addition, one or more hydrogen atoms among the organic groups constituting Z may be substituted with halogen atoms such as fluorine, chlorine, bromine and iodine.

Further, the organic group containing such a carboxyl group may be, for example, an organic group represented by the following formula (9).

In the present embodiment, in the structural unit having an oxetanyl group having a structure derived from norbornene represented by the above general formula, at least one of R ₁ , R ₂ , R ₃ and R ₄ contains an oxetane group. It is more preferably an organic group. Thereby, the stability with time and the thermal flow resistance of the photosensitive resin film obtained by using the photosensitive resin composition having the polymer of the present embodiment can be improved. For example, by using the structural unit having an oxetanyl group having a structure derived from norbornene as described above, the stability over time can be improved as compared with the case where the structural unit derived from norbornene having a glycidyl group is used. In addition, heat resistance and mechanical strength can be improved.

Further, from the viewpoint of enhancing the light transmittance of the photosensitive resin film made of a polymer, R ₁ , R ₂ , R ₃ , and R ₁ , R ₂ , and R ₃ are used in the structural unit having an oxetanyl group having a structure derived from norbornene represented by the above general formula. either R ₄ is preferably a hydrogen, it is preferred that all but oxetanyl group is hydrogen.

Further, from the viewpoint of the balance between the rework property and the solvent resistance, the polymer of the present embodiment contains a structural unit having an oxetanyl group having a structure derived from norbornene and a structural unit derived from norbornene having a carboxyl group. May be good.

In the present embodiment, the structural unit derived from the N-substituted maleimide may be represented by, for example, the following general formula. These may be used alone or in combination of two or more.

In the above general formula, X is an alkyl group having 1 to 15 carbon atoms and 6 to 14 carbon atoms substituted with one or more selected from the group consisting of a hydroxy group, a hydroxyalkyl group, a carboxy group and a carboxyalkyl group. It shows an aryl group or a cycloalkyl group having 3 to 12 carbon atoms.

X in the above general formula may have an alkyl group having 1 to 15 carbon atoms, may have an alkyl group having 1 to 13 carbon atoms, and an alkyl having 1 to 10 carbon atoms. It may have a group. For example, examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group and a pentyl group. Examples thereof include neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group and the like.
Here, the hydroxyalkyl group or the alkyl group contained in the carboxyalkyl group may have the alkyl group having 1 to 15 carbon atoms.
Further, X in the above general formula may have an aryl group having 6 to 14 carbon atoms, may have an aryl group having 6 to 12 carbon atoms, and may have an aryl group having 6 to 10 carbon atoms. May have. For example, examples of the aryl group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group.
Further, X in the above general formula may have a cycloalkyl group having 3 to 12 carbon atoms, may have a cycloalkyl group having 3 to 11 carbon atoms, and has 3 to 10 carbon atoms. It may have a cycloalkyl group. For example, examples of the cycloalkyl group having 3 to 10 carbon atoms include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.
In addition to the above-mentioned alkyl group, aryl group and cycloalkyl group, X in the above general formula may have other hydrocarbon groups such as an alkenyl group, an alkynyl group, an alkylidene group, an aralkyl group and an alkalil group. Good. In this case, as the other hydrocarbon group constituting X in the above general formula, an organic group having 1 to 10 carbon atoms may be used, for example, an alkenyl group, an alkynyl group, an alkylidene group, an aralkyl group, or an alkalil group. And the like, hydrocarbon groups having 1 to 10 carbon atoms can be mentioned. Examples of such an alkenyl group include an allyl group, a pentenyl group, and a vinyl group. Examples of the alkynyl group include an ethynyl group. Examples of the alkylidene group include a methylidene group and an ethylidene group. Examples of the aralkyl group include a benzyl group and a phenethyl group. Examples of the alkaline group include a tolyl group and a xylyl group.
In addition, one or more hydrogen atoms contained in X in the above general formula may be substituted with halogen atoms such as fluorine, chlorine, bromine and iodine.

The structural unit derived from the N-substituted maleimide having a hydroxy group may be represented by, for example, the following general formula.

In the above general formula, R ₅ represents a hydroxy group.
In the present embodiment, by using the structural unit derived from the N-substituted maleimide having a hydroxy group, the polymer of the present embodiment and the photosensitive resin film made of the polymer can be sufficiently made highly sensitive.
In the general formula, hydroxy group for R ₅ is a structure directly bonded to the benzene ring ortho position of the benzene ring, meta, or it be attached to any of the para position, for example, meta or It is preferable to bind to the para position.

On the other hand, the structural unit derived from the N-substituted maleimide having the above carboxy group may be represented by, for example, the following general formula.

R ₉ in the above general formula is an alkyl group having 1 to 15 carbon atoms substituted with one or more carboxy groups.
As the alkyl group having 1 to 15 carbon atoms in R ₉ , an alkyl group having 1 to 15 carbon atoms in X can be used. The lower limit of the number of carbon atoms of the alkyl group in R ₉ is not particularly limited, but is, for example, 1, preferably 3 or more, more preferably 5 or more, and further preferably 8 or more. .. Thereby, the flexibility of the polymer of the present embodiment and the photosensitive resin film made of the polymer can be improved. As a result, the photosensitive resin film of the present embodiment can be suitably used for thick film applications. In addition, the adhesion to the base substrate can be improved. As a result, the applicable range of the base substrate can be expanded and the development margin can be expanded.

In the present embodiment, the structural unit derived from the N-substituted maleimide having a hydroxy group is, for example, N-hydroxymaleimide, N-hydroxymethylmaleimide, N- (2-hydroxyethyl) maleimide, N- (3-hydroxypropyl). ) Maleimide, N- (4-hydroxybutyl) maleimide, N- (2-hydroxycyclohexyl) maleimide, N- (3-hydroxycyclohexyl) maleimide, N- (4-hydroxycyclohexyl) maleimide, N- (2-hydroxymethyl) Cyclohexyl) maleimide, N- (2-hydroxymethylphenyl) maleimide, N- (3-hydroxymethylphenyl) maleimide, N- (4-hydroxymethylphenyl) maleimide, N- (4-hydroxymethyl-3,5-dimethyl) Phenyl) maleimide, N- (4-hydroxymethyl-2,6-dimethylphenyl) maleimide, N- (2-hydroxyphenyl) maleimide, N- (3-hydroxyphenyl) maleimide, N- (4-hydroxyphenyl) maleimide , N- (4-hydroxy-3,5-dimethylphenyl) maleimide, N- (4-hydroxy-2,6-dimethylphenyl) maleimide, N- (2-hydroxybenzyl) maleimide, N- (3-hydroxybenzyl) ) Maleimide, N- (4-hydroxybenzyl) maleimide, N- (4-hydroxy-3,5-dimethylbenzyl) maleimide, N- (4-hydroxy-2,6-dimethylbenzyl) maleimide can be included.

In the present embodiment, the structural unit derived from the N-substituted maleimide having a carboxy group is, for example, N- (2-carboxyphenyl) maleimide, N- (3-carboxyphenyl maleimide, N- (4-carboxyphenyl) maleimide). , N- (4-carboxy-3,5-dimethylphenyl) maleimide, N- (4-carboxy-3,5-dimethylbenzyl) maleimide, N- (4-carboxy-2,6-dimethylbenzyl) maleimide, N -(2-carboxybenzyl) maleimide, N- (3-carboxybenzyl maleimide, N- (4-carboxybenzyl) maleimide, N- (4-carboxy-3,5-dimethylbenzyl) maleimide, N- (4-carboxy) -2,6-dimethylbenzyl) maleimide, N- (2-carboxycyclohexyl) maleimide, N- (3-carboxycyclohexylmaleimide, N- (4-carboxycyclohexyl) maleimide, N- (2-carboxymethylcyclohexyl) maleimide, N- (3-carboxymethylcyclohexyl) maleimide, N- (4-carboxymethylcyclohexyl) maleimide and the like can be included.

The polymer of the present embodiment can contain both the structural unit derived from the N-substituted maleimide having the hydroxy group and the structural unit derived from the N-substituted maleimide having the carboxy group. As a result, it is possible to improve the sensitivity and the stability over time, and also to improve the adhesion to the substrate and the development margin.

In addition, the polymer of the present embodiment can further contain a structural unit derived from a fumaric acid diester monomer represented by the following formula.

In the above formula, a is an integer of 2-9.
As a result, the rework characteristics, chemical resistance, and transparency of the polymer of the present embodiment and the photosensitive resin film made of the polymer can be improved.

In addition, the polymer of the present embodiment can further contain a structural unit derived from maleimide represented by the following general formula.

R ₆ in the above general formula is a hydrogen, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 8 carbon atoms. The R ₆ may have a cycloalkyl group having an alicyclic skeleton.
In the present embodiment, by using a maleimide-derived structural unit represented by the above general formula, a photosensitive resin film having heat resistance, transparency, low dielectric constant, low birefringence, chemical resistance, water repellency, etc. is required. It is possible to improve the rework characteristics while maintaining the various characteristics. That is, various properties of the polymer of the present embodiment and the photosensitive resin film made of the polymer can be adjusted.

Regarding an example of the structure of the polymer of the present embodiment, the structural unit having an oxetanyl group having a structure derived from norbornene is A, the structural unit derived from norbornene having a carboxyl group is B, and the structural unit derived from N-substituted maleimide having a hydroxy group Will be described as C, and the structural unit derived from N-substituted maleimide having a carboxy group is D.
For example, the polymer of this embodiment may have at least A and C. This makes it possible to improve the balance between stability over time, high sensitivity and thermal flow resistance.
Further, the polymer of the present embodiment may contain A, B and C, and may contain A, C and D. By using D instead of C, it is possible to improve the sensitivity and the stability over time. Further, the adhesion to the substrate can be improved, and the development margin can be widened. Further, the flexibility can be increased by using D having a long chain alkyl carboxylate.

The molar ratio of the structural unit having an oxetanyl group having the structure derived from norbornene in the polymer of the present embodiment is not particularly limited, but may be 10 or more and 80 or less, and 15 or more and 60 or less, for example, with respect to the entire polymer 100. It may be 20 or more and 50 or less. This makes it possible to improve the balance between stability over time, high sensitivity and thermal flow resistance.

The molar ratio of the structural unit derived from the N-substituted maleimide in the polymer of the present embodiment is not particularly limited with respect to the entire polymer 100, but may be, for example, 10 or more and 90 or less with respect to the entire polymer 100. It may be 20 or more and 80 or less. This makes it possible to improve the balance between stability over time, high sensitivity and thermal flow resistance.

The polymer of the present embodiment can be synthesized, for example, as follows.

(Polymerization step (treatment S1))
First, as a monomer, a norbornene-type monomer having an oxetanyl group and an N-substituted maleimide having a hydroxy group or a carboxy group are prepared.

Next, these prepared monomers are addition-polymerized to obtain a copolymer (copolymer 1). Here, addition polymerization is carried out by, for example, radical polymerization. In the present embodiment, solution polymerization can be carried out by dissolving the above-mentioned monomer and the polymerization initiator in a solvent and then heating for a predetermined time. At this time, the heating temperature can be, for example, 50 ° C to 80 ° C. The heating time can be, for example, 1 hour to 20 hours. It is more preferable to carry out solution polymerization after removing dissolved oxygen in the solvent by nitrogen bubbling.
In addition, a molecular weight modifier or a chain transfer agent can be used as needed. Examples of the chain transfer agent include thiol compounds such as dodecyl mercaptoethanol, mercaptoethanol, and 4,4-bis (trifluoromethyl) -4-hydroxy-1-mercaptobutane. These chain transfer agents may be used alone or in combination of two or more.

As the solvent used in the above solution polymerization, for example, one or more of esters such as methyl ethyl ketone (MEK), propylene glycol monomethyl ether, diethyl ether, tetrahydrofuran (THF), toluene, ethyl acetate and butyl acetate should be used. Can be done. Further, as the polymerization initiator, one or more of the azo compound and the organic peroxide can be used. Examples of the azo compound include azobisisobutyronitrile (AIBN), dimethyl 2,2'-azobis (2-methylpropionate), and 1,1'-azobis (cyclohexanecarbonitrile) (ABCN). Examples of organic peroxides include hydrogen peroxide, di-tert-butyl peroxide (DTBP), benzoyl peroxide (benzoyl peroxide (BPO)) and methyl ethyl ketone peroxide (MEKP).

The reaction solution containing the copolymer 1 thus obtained is added to hexane or methanol to precipitate the polymer. Then, the polymer is collected by filtration, washed with hexane, methanol, or the like, and then dried. In this embodiment, the polymer can be synthesized, for example, in this way.

(Washing step (treatment S2))
The reaction solution containing the copolymer 1 thus obtained is added to a hydrocarbon such as hexane or heptane or an alcohol such as methanol to precipitate a polymer. Next, the polymer is collected by filtration, washed with a hydrocarbon such as hexane or heptane, or an alcohol such as methanol, and then dried. In this embodiment, the polymer can be synthesized, for example, in this way.

(Photosensitive resin composition)
Next, the photosensitive resin composition of the present embodiment will be described.
The photosensitive resin composition of the present embodiment contains the above-mentioned polymer. In the present embodiment, this photosensitive resin composition may be used, for example, to form a permanent film.

In the present embodiment, the permanent film is composed of a cured film obtained by curing the photosensitive resin film made of the photosensitive resin composition of the present embodiment. In the present embodiment, for example, a coating film (photosensitive resin film) composed of a photosensitive resin composition is patterned into a desired shape by exposure and development, and then the coating film is cured by heat treatment or the like to form a permanent film. Is formed.

Examples of the permanent film formed by using the photosensitive resin composition of the present embodiment include an interlayer film, a surface protective film, and a dam material. The permanent film can also be used as an optical material such as an optical lens. The use of the permanent film is not limited to these.
The interlayer film refers to an insulating film provided in the multilayer structure, and the type thereof is not particularly limited. Examples of the interlayer film include those used in semiconductor device applications such as an interlayer insulating film constituting a multilayer wiring structure of a semiconductor element, a build-up layer or a core layer constituting a circuit board. Further, as the interlayer film, for example, a flattening film for covering a thin film transistor (TFT (Thin Film Transistor)) in a display device, a liquid crystal alignment film, and a protrusion provided on a color filter substrate of an MVA (Multi Domino Vertical Organic) type liquid crystal display device. Alternatively, those used in display device applications such as partition walls for forming a cathode of an organic EL element can also be mentioned.
The surface protective film refers to an insulating film formed on the surface of an electronic component or an electronic device and for protecting the surface, and the type thereof is not particularly limited. Examples of such a surface protective film include a passivation film provided on a semiconductor element, a bump protective film or a buffer coat layer, and a cover coat provided on a flexible substrate.
The dam material is a spacer used for forming a hollow portion for arranging an optical element or the like on a substrate.

The photosensitive resin composition according to the present embodiment can contain one or more of the polymers exemplified above. The content of the polymer in the photosensitive resin composition is not particularly limited, but may be 20% by mass or more and 90% by mass or less, and 30% by mass or more and 80% by mass with respect to the total solid content of the photosensitive resin composition. It may be less than or equal to%.
The solid content of the photosensitive resin composition refers to a component excluding the solvent contained in the photosensitive resin composition. Hereinafter, the same applies to the present specification.

The photosensitive resin composition of the present embodiment may contain a solvent. Examples of the solvent include propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), ethyl lactate, methyl isobutyl carbinol (MIBC), gamma butyrolactone (GBL), N-methylpyrrolidone (NMP), and methyl. n-Amilketone (MAK), diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, cyclohexanone, or a mixture thereof can be adopted. It should be noted that the present invention is not limited to the one illustrated here.
The amount of this solvent added can be appropriately set according to the application to which the positive photosensitive resin composition is applied.

The photosensitive resin composition of the present embodiment may be a positive type photosensitive resin composition or a negative type photosensitive resin composition.

The above-mentioned positive photosensitive resin composition can contain the above-mentioned polymer and a photosensitizer.

As the photosensitizer, for example, a diazoquinone-based photosensitizer (diazoquinone compound) can be used. The diazoquinone-based photosensitizer (diazoquinone compound) includes, for example, those exemplified below.

(N2 is an integer of 1 or more and 5 or less)

In each of the above compounds, Q is any one of the following structures (a), structure (b) and structure (c), or a hydrogen atom. However, at least one of Q contained in each compound is any one of structure (a), structure (b) and structure (c). From the viewpoint of transparency and dielectric constant of the photosensitive resin composition, an o-naphthoquinonediazide sulfonic acid derivative having Q having a structure (a) or a structure (b) is more preferable.

The content of the photosensitizer in the positive photosensitive resin composition is preferably 1 part by mass or more and 40 parts by mass or less, and 5 parts by mass or more and 35 parts by mass or less, based on 100 parts by mass of the entire polymer. Is more preferable. This makes it possible to effectively improve the balance between reactivity, stability over time, and developability in the positive photosensitive resin composition.

The positive photosensitive resin composition can contain, for example, an acid generator that generates an acid by light or heat. Examples of photoacid generators that generate acid by light include triphenylsulfonium trifluoromethanesulfonate, tris (4-t-butylphenyl) sulfonium-trifluoromethanesulfonate, and diphenyl [4- (phenylthio) phenyl] sulfonium trifluorotris. Pentafluoroethyl phosphate, sulfonium salts such as diphenyl [4- (phenylthio) phenyl] sulfonium tetrakis (pentafluorophenyl) borate, diazonium salts such as p-nitrophenyldiazonium hexafluorophosphate, ammonium salts, phosphonium salts, diphenyliodonium trifluo Lomethanesulfonate, iodonium salts such as (tricumyl) iodonium-tetrakis (pentafluorophenyl) borate, quinonediazides, diazomethanes such as bis (phenylsulfonyl) diazomethane, 1-phenyl-1- (4-methylphenyl) sulfonyloxy-1 -Sulfonic acid esters such as benzoylmethane, N-hydroxynaphthalimide-trifluoromethanesulfonate, disulfones such as diphenyldisulfone, tris (2,4,6-trichloromethyl) -s-triazine, 2- (3,4) It can have compounds such as triazines such as −methylenedioxyphenyl) -4,6-bis- (trichloromethyl) -s-triazine. The positive photosensitive resin composition in the present embodiment may contain one or more photoacid generators exemplified above.

Examples of acid generators (thermoacid generators) that generate acid by heat include SI-45L, SI-60L, SI-80L, SI-100L, SI-110L, and SI-150L (Sanshin Chemical Industry Co., Ltd.). It can have an aromatic sulfonium salt such as (manufactured by). The positive photosensitive resin composition in the present embodiment may contain one or more of the thermal acid generators exemplified above. Further, in the present embodiment, the photoacid generator exemplified above and these thermoacid generators can be used in combination.

When the positive photosensitive resin composition contains an acid generator, the content thereof is preferably 0.1 part by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the entire polymer, and 0.5 parts by mass. It is more preferably 10 parts by mass or less. This makes it possible to effectively improve the balance between reactivity, stability over time, and developability in the positive photosensitive resin composition.

Further, the negative photosensitive resin composition according to the present embodiment may contain a photoradical generator in addition to the above-mentioned polymer.

Specific examples of the photoradical generator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenylketone, and 2-hydroxy-2-methyl-1-. Phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propane-1-one, 2-hydroxy-1- {4- [4- (2) -Hydroxy-2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane 1-one, 2-benzyl-2- Dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1 -Alkylphenyl compounds such as butanone; benzophenone, 4,4'-bis (dimethylamino) benzophenone, 2-carboxybenzophenone and other benzophenone compounds; Benzoin compounds; thioxanthone compounds such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 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 Halomethylated triazine compounds such as (trichloromethyl) -s-triazine, 2- (4-ethoxycarbokynylnaphthyl) -4,6-bis (trichloromethyl) -s-triazine; 2-trichloromethyl-5- (2) '-Benzofuryl) -1,3,4-oxadiazole, 2-trichloromethyl-5-[β- (2'-benzofuryl) vinyl] -1,3,4-oxadiazole, 4-oxadiazole, Halomethylated oxadiazole compounds such as 2-trichloromethyl-5-furyl-1,3,4-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 Biimidazole compounds such as'-tetraphenyl-1,2'-biimidazole; 1,2-octanedione, 1- [4- (phenylthio) -2- (O-benzoyloxime)], etanone, 1-[ Oxime ester compounds such as 9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-acetyloxime); bis (η5-2,4-cyclopentadiene-1) -Il) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanosen compounds such as titanium; benzoic acid esters such as p-dimethylaminobenzoic acid and p-diethylaminobenzoic acid System compounds; Acridine compounds such as 9-phenylacridin; and the like.

The negative photosensitive resin composition of the present embodiment may contain, for example, a melamine-based cross-linking agent as a curing agent for phenolic hydroxyl groups.
Examples of the melamine-based cross-linking agent include hexamethoxymethylmelamine, hexaethoxymethylmelamine, hexapropoxymethylmelamine, hexabutoxybutyl melamine and the like, and hexamethoxymethylmelamine is preferable.
The content of the melamine-based cross-linking agent is, for example, 5 to 40% by mass when the total solid content of the negative photosensitive resin composition is 100% by mass, and is more preferably 5 from the viewpoint of curability. It is ~ 30% by mass, more preferably 10 to 25% by mass.

In the negative photosensitive resin composition of the present embodiment, the content of the photoradical generator is preferably 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the entire polymer, and further, 8 parts by mass. It is preferably 15 parts by mass or less.

Further, by using a photosensitizer or a photoradical polymerization accelerator together with the above photoradical generator, the sensitivity and the degree of cross-linking can be further improved. For example, pigment compounds such as xanthene dyes and coumarin dyes, dialkylaminobenzene compounds such as ethyl 4-dimethylaminobenzoate and 2-ethylhexyl 4-dimethylaminobenzoate, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole and the like. Examples include mercapto hydrogen donors.

Further, the photosensitive resin composition of the present embodiment has a filler, a binder resin other than the above-mentioned polymer, an acid generator, a heat resistance improver, a developing aid, a plasticizer, and a polymerization according to the purpose and required characteristics of each application. Prohibition agents, UV absorbers, antioxidants, matting agents, defoaming agents, leveling agents, antistatic agents, dispersants, slip agents, surface modifiers, rocking agents, rocking aids, silanes and aluminum Ingredients other than the above essential components such as a system, a titanium-based coupling agent, and a polyhydric phenol compound may be blended.

For example, the photosensitive resin composition of the present embodiment containing a colorant can be used as a colored photosensitive resin composition. Conventionally known pigments and dyes can be used as the colorant.
The colored photosensitive resin composition can be suitably used, for example, when producing a black matrix or a coloring pattern constituting a color filter.

The photosensitive resin composition of the present embodiment (positive type photosensitive resin composition, negative type photosensitive resin composition) can obtain a resin film obtained by making it a cured product.
Considering the high heat resistance, such a resin film can form, for example, a protective film, an interlayer film, or a permanent film such as a dam material. As a result, it is possible to improve the durability and the like of the electronic device provided with the resin film as a permanent film.

Since the photosensitive resin composition (positive type photosensitive resin composition, negative type photosensitive resin composition) of the present embodiment uses a specific polymer, it has excellent heat resistance when a cured product is obtained. Give a cured product.
The 5% weight loss temperature of the cured product is preferably 335 ° C. or higher, more preferably 340 ° C. or higher.
The 5% weight loss temperature can be defined as a 5% weight loss temperature in the atmosphere by using, for example, a heat balance device (“TG-DTA2000” manufactured by Bruker AS Corporation).

(Electronic device)
Next, an example of the electronic device 100 of the present embodiment will be described.
The electronic device 100 of the present embodiment can include a cured product of a photosensitive resin film made of the above-mentioned photosensitive resin composition.
The electronic device 100 shown in FIG. 1 is, for example, a semiconductor package in which a semiconductor chip is mounted on a wiring board. For example, a semiconductor package can be obtained by mounting a semiconductor chip on a wiring board via bumps 52. The electronic device 100 includes a semiconductor substrate provided with a semiconductor element such as a transistor, and a multilayer wiring layer provided on the semiconductor substrate (not shown). The uppermost layer of the multilayer wiring layer is provided with an interlayer insulating film 30 and an uppermost layer wiring 34 provided on the interlayer insulating film 30. The top layer wiring 34 is made of, for example, aluminum. Further, a passivation film 32 is provided on the interlayer insulating film 30 and on the uppermost layer wiring 34. A part of the passivation film 32 is provided with an opening in 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, and an insulating layer 44 provided on the insulating layer 42 and the rewiring 46. Has. The insulating layer 42 is formed with an opening for connecting to the uppermost layer wiring 34. The rewiring 46 is formed on the insulating layer 42 and in the openings provided in the insulating layer 42, and is connected to the uppermost layer wiring 34. The insulating layer 44 is provided with an opening for connecting to the rewiring 46.
In the present embodiment, one or more of the passivation film 32, the insulating layer 42, and the insulating layer 44 is formed of, for example, a resin film formed by curing a photosensitive resin film made of the above-mentioned photosensitive resin composition. Can be configured. In this case, for example, the coating film formed of the photosensitive resin material is exposed to ultraviolet rays, developed, and then patterned, and then heat-cured to form the passivation film 32, the insulating layer 42, or the insulating layer 44. It is formed.

Bumps 52 are formed in the openings provided in the insulating layer 44, for example, via the UBM (Under Bump Metallurgy) layer 50. The electronic device 100 is connected to a wiring board or the like via, for example, a bump 52.

Although the embodiments of the present invention have been described above with reference to the drawings, these are examples of the present invention, and various configurations other than the above can be adopted.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the description of these Examples.

<Synthesis of polymer>
(Synthesis Example 1: Synthesis of Polymer 1)
In the reaction vessel, oxetane norbornene (5.9 g, 0.025 mol) represented by the following formula (25), norbornene carboxylic acid (17.3 g, 0.125 mol), methyl glycidyl ether norbornene (13.5 g, 0.075 mol). ), Dibutyl fumarate (5.7 g, 0.025 mol), V-601 (4.6 g, 0.02 mol) and 8.4 g of MEK were added, and the mixture was stirred and dissolved. Then, after removing the dissolved oxygen in the system by nitrogen bubbling, it was heated, and when the internal temperature reached 70 ° C., 4-hydroxyphenylmaleimide (21.3 g, 0.113 mol) and cyclohexylmaleimide (24. A solution prepared by dissolving 6 g, 0.137 mol) in 45.9 g of MEK was added over 6 hours. Then, it reacted at 70 degreeC for 3 hours. The reaction mixture was then cooled to room temperature and 147 g of MEK was added and diluted. The diluted solution was poured into a large amount of heptane to precipitate the polymer. The polymer was then collected by filtration, further washed with heptane and then vacuum dried at 30 ° C. for 16 hours. The yield of the polymer was 67 g, and the yield was 76%. The polymer had a weight average molecular weight Mw of 6,080, a dispersity (weight average molecular weight Mw / number average molecular weight Mn) of 1.89, and an alkali dissolution rate of 1,300 Å / sec.

For the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the obtained polymer, polystyrene-equivalent values obtained from the calibration curve of standard polystyrene (PS) obtained by GPC measurement were used. The measurement conditions are as follows.
Gel Permeation Chromatographer HLC-8320GPC manufactured by Tosoh Corporation
Column: TSK-GEL Supermultipore HZ-M manufactured by Tosoh Corporation
Detector: RI detector for liquid chromatogram Measurement temperature: 40 ° C
Solvent: THF
Sample concentration: 2.0 mg / ml The measurement conditions for the weight average molecular weight (Mw) and the number average molecular weight (Mn) are the same in Synthesis Examples 2 to 6 described later.

(Dissolution rate)
The dissolution rate of the obtained polymer was measured as follows. First, the polymer solution obtained above was applied onto a silicon wafer by a spin method and then heat-treated at 100 ° C. for 120 seconds to obtain a polymer film having a film thickness H of 2.0 μm. Next, the polymer film was impregnated with a 0.5% tetramethylammonium hydroxide aqueous solution at 23 ° C., and the time T until the polymer film was visually erased was measured. Then, based on the measured values obtained thereby, the film thickness H / hour T was calculated as the dissolution rate (Å / sec).

(Synthesis Example 2: Synthesis of Polymer 2)
Oxetane norbornene (23.6 g, 0.100 mol), norbornene carboxylic acid (17.3 g, 0.125 mol), dibutyl fumarate (5.7 g, 0.025 mol), V-601 (4.6 g) in the reaction vessel. , 0.02 mol) and 6.8 g of MEK were added, and the mixture was stirred and dissolved. Then, after removing the dissolved oxygen in the system by nitrogen bubbling, it was heated, and when the internal temperature reached 70 ° C., 4-hydroxyphenylmaleimide (21.3 g, 0.113 mol) and cyclohexylmaleimide (24. A solution prepared by dissolving 6 g, 0.137 mol) in 64.3 g of MEK was added over 6 hours. Then, it reacted at 70 degreeC for 3 hours. The reaction mixture was then cooled to room temperature and 140 g of MEK was added and diluted. The diluted solution was poured into a large amount of heptane to precipitate the polymer. The polymer was then collected by filtration, further washed with heptane and then vacuum dried at 30 ° C. for 16 hours. The yield of the polymer was 63 g, and the yield was 68%. The polymer had a weight average molecular weight Mw of 5,600, a dispersity (weight average molecular weight Mw / number average molecular weight Mn) of 1.75, and an alkali dissolution rate of 1,210 Å / sec.
(Synthesis Example 3: Synthesis of Polymer 3)
Oxetane norbornene (47.2 g, 0.200 mol), V-601 (3.68 g, 0.016 mol) and MEK 29.7 g were added to the reaction vessel, and the mixture was stirred and dissolved. Then, after removing the dissolved oxygen in the system by nitrogen bubbling, the mixture was heated, and when the internal temperature reached 70 ° C., 4-hydroxyphenylmaleimide (22.7 g, 0.120 mol) and cyclohexylmaleimide (7. A solution prepared by dissolving 16 g, 0.04 mol) and maleimide phenylic acid (11.24 g, 0.04 mo) in 102.7 g of MEK was added over 3 hours. Then, the reaction was carried out at 70 ° C. for 3 hours and further at 83 ° C. for 3 hours. The reaction mixture was then cooled to room temperature and 70 g of acetone was added and diluted. The diluted solution was poured into a large amount of heptane to precipitate the polymer. The polymer was then collected by filtration, washed further with heptane and then vacuum dried at 40 ° C. for 16 hours. The yield of the polymer was 65 g, and the yield was 74%. The polymer had a weight average molecular weight Mw of 3,600, a dispersity (weight average molecular weight Mw / number average molecular weight Mn) of 1.71, and an alkali dissolution rate of 620 Å / sec.
(Synthesis Example 4: Synthesis of Polymer 4)
Oxetane norbornene (47.2 g, 0.200 mol), V-601 (3.68 g, 0.016 mol) and MEK 29.7 g were added to the reaction vessel, and the mixture was stirred and dissolved. Next, after removing the dissolved oxygen in the system by nitrogen bubbling, the mixture was heated, and when the internal temperature reached 70 ° C., 3-hydroxyphenylmaleimide (manufactured by Seiko Kagaku Co., Ltd., 22.7 g, 0.120 mol), A solution prepared by dissolving cyclohexylmaleimide (7.16 g, 0.04 mol) and maleimide undecanoic acid (11.24 g, 0.04 mo) in MEK102.7 g was added over 3 hours. Then, the reaction was carried out at 70 ° C. for 3 hours and further at 83 ° C. for 3 hours. The reaction mixture was then cooled to room temperature and 70 g of acetone was added and diluted. The diluted solution was poured into a large amount of heptane to precipitate the polymer. The polymer was then collected by filtration, washed further with heptane and then vacuum dried at 40 ° C. for 16 hours. The yield of the polymer was 74 g, and the yield was 83%. The polymer had a weight average molecular weight Mw of 3,300, a dispersity (weight average molecular weight Mw / number average molecular weight Mn) of 1.85, and an alkali dissolution rate of 520 Å / sec.

(Synthesis Example 5: Synthesis of Polymer 5)
Oxetane norbornene (11.8 g, 0.05 mol), norbornene carboxylic acid (27.6 g, 0.20 mol), methylglycidyl ether norbornene (27.0 g, 0.15 mol), dibutyl fumarate in a hermetically sealed reaction vessel. (22.8 g, 0.10 mol), V-601 (9.2 g, 0.04 mol) and 26.6 g of MEK were added, and the mixture was stirred and dissolved. Then, after removing the dissolved oxygen in the system by nitrogen bubbling, the mixture was heated, and when the internal temperature reached 70 ° C., maleimide (21.8 g, 0.225 mol) and cyclohexyl maleimide (49.3 g, 0. A solution prepared by dissolving 275 mol) in 71.1 g of MEK was added over 6 hours. Then, it reacted at 70 degreeC for 3 hours. The reaction mixture was then cooled to room temperature and 266 g of MEK was added and diluted. The diluted solution was poured into a large amount of heptane to precipitate the polymer. The polymer was then collected by filtration, further washed with heptane and then vacuum dried at 30 ° C. for 16 hours. The yield of the polymer was 112 g, and the yield was 70%. The polymer had a weight average molecular weight Mw of 5,930, a dispersity (weight average molecular weight Mw / number average molecular weight Mn) of 1.89, and an alkali dissolution rate of 930 Å / sec.

<Preparation of photosensitive resin composition>
(Example 1)
(Preparation of photosensitive resin composition)
10.0 g of polymer 1 synthesized in Synthesis Example 1 with 1,4'-(1- {4- [1- (4-hydroxyphenyl) -1-methylethyl] phenyl} ethylidene) bisphenol and 1,2- 2.25 g of esterified product with naphthoquinone diazide-5-sulfonyl chloride (manufactured by Daito Chemix Co., Ltd .: PA-28), ε-caprolactone-modified 3,4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (Co., Ltd.) 3.0 g of CEL2081) manufactured by Daicel, 3.0 g of KBM-803 (manufactured by Shinetsu Silicone Co., Ltd.) to improve adhesion, to prevent radial striations formed on the ester film during rotary coating. 0.05 g of F-556 (manufactured by DIC) was dissolved in a mixed solvent of propylene glycol monomethyl ether acetate: diethylene glycol ethyl methyl ether = 50: 50 so as to have a solid content of 20%. This was filtered through a 0.2 μm PTFE filter to prepare a positive photosensitive resin composition.
The following evaluation was performed on the obtained photosensitive resin composition. The results obtained are shown in Table 1.

(Formation of thin film pattern)
A thin film pattern was formed as follows. First, the obtained photosensitive resin composition was rotationally applied to a Corning 1737 glass substrate having a size of 100 mm in length and 100 mm in width (rotation speed: 300 to 2500 rpm), baked on a hot plate at 100 ° C. for 120 seconds, and then about. A thin film A having a thickness of 5.5 μm was obtained. This thin film A is exposed to a g + h + i-line mask aligner (PLA-501F) manufactured by Canon Inc. via a 10 μm mask pattern, and developed at 23 ° C. for 120 seconds using a 0.5 mass% tetramethylammonium hydroxide aqueous solution. By doing so, a thin film B with a pattern was obtained. This thin film B was exposed to the entire surface at 300 mJ / cm ² with PLA-501F and then post-baked by heating in an oven at 230 ° C. for 60 minutes to obtain a patterned thin film C.

(Remaining film ratio after development and post-baking)
From the film thicknesses of the thin film A, the thin film B, and the thin film C obtained by forming the thin film pattern described above, the residual film ratio was calculated from the following formula.
Residual film ratio after development (%) = [Film thickness of thin film B (μm) / Film thickness of thin film A (μm)] × 100
Post-baking residual film ratio (%) = [Thin film C film thickness (μm) / Thin film A film thickness (μm)] × 100

(sensitivity)
The minimum exposure amount at which film loss was observed in a hole pattern of 10 μm was defined as the sensitivity.

(Thermal flow)
In the 10 μm hole pattern after post-baking, those with no change in shape were marked with ◯, and those with significant changes in pattern deformation and CD were marked with x. 2 (a) and 2 (b) show a cross-sectional photograph of Example 2, and FIGS. 2 (c) and 2 (d) show a cross-sectional photograph of Comparative Example 1. In the cross-sectional photograph, the area area is 10 μm × 10 μm, FIGS. 2 (a) and 2 (c) show the developed one, and FIGS. 2 (b) and 2 (d) show the one after firing (post-baking).

(Stability over time)
The viscosity of the photosensitive resin composition at 25 ° C. immediately after the preparation was measured using an E-type viscometer, and this was defined as the initial viscosity η ₀ . Further, the closed container containing the above-mentioned photosensitive resin composition immediately after preparation is stored at a temperature of 40 ± 1 ° C. for 14 days, and the viscosity of the photosensitive resin composition after storage at 25 ° C. is measured, and this is determined as the viscosity η. _{It was set to 1} . Then, from these measurement results, the viscosity change rate η ₁ / η ₀ × 100 was calculated. Here, the stability with time was evaluated by ◯ for the viscosity change rate of 150% or less and x for the viscosity change rate exceeding 150%. The results are shown in Table 1.

(Example 2)
A photosensitive resin composition was prepared in the same manner as in Example 1 except that the polymer 1 synthesized in Synthesis Example 1 was changed to the polymer 2 synthesized in Synthesis Example 2, and each of the above evaluations was performed. The results obtained are shown in Table 1.

(Example 3)
10.0 g of polymer 3 synthesized according to Synthesis Example 3 and 1,4'-(1- {4- [1- (4-hydroxyphenyl) -1-methylethyl] phenyl} ethylidene) bisphenol and 1,2- 1.5 g of esterified product with naphthoquinone diazide-5-sulfonyl chloride (manufactured by Daitokemix Co., Ltd .: PA-28), 0.5 g of KBM-403 (manufactured by Shinetsu Silicone Co., Ltd.) to improve adhesion, curing reaction SI-110 (manufactured by Sanshin Kagaku Kogyo Co., Ltd.) is 0.5 g to promote, and F-556 (manufactured by DIC) is 0 to prevent radial striations formed on the ester film during rotary coating. 0.05 g was dissolved in a mixed solvent of propylene glycol monomethyl ether acetate: diethylene glycol ethyl methyl ether = 50: 50 so as to have a solid content of 20%. This was filtered through a 0.2 μm PTFE filter to prepare a positive photosensitive resin composition.
Each of the above evaluations was performed on the obtained photosensitive resin composition. The results obtained are shown in Table 1.

(Example 4)
A photosensitive resin composition was prepared in the same manner as in Example 3 except that the polymer 3 synthesized in Synthesis Example 3 was changed to the polymer 4 synthesized in Synthesis Example 4, and each of the above evaluations was performed. The results obtained are shown in Table 1.

(Comparative Example 1)
The polymer 5 synthesized in Synthesis Example 5 is obtained from 10.0 g, 4,4'-(1- {4- [1- (4-hydroxyphenyl) -1-methylethyl] phenyl} ethylidene) bisphenol and 1,2. 2.13 g of esterified product with -naphthoquinone diazide-5-sulfonyl chloride (manufactured by Daito Chemix Co., Ltd .: PA-28), ε-caprolactone modified 3,4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (stock) 3.0 g of CEL2081) manufactured by Daicel Co., Ltd., 3.0 g of KBM-803 (manufactured by Shinetsu Silicone Co., Ltd.) to improve adhesion, and prevent radial striations formed on the ester film during rotary coating. Therefore, 0.03 g of F-556 (manufactured by DIC) was dissolved in a mixed solvent of propylene glycol monomethyl ether acetate: diethylene glycol ethyl methyl ether = 50: 50 so as to have a solid content of 20%. This was filtered through a 0.2 μm PTFE filter to prepare a positive photosensitive resin composition.
The following evaluation was performed on the obtained photosensitive resin composition. The results obtained are shown in Table 1.

(Comparative Example 2)
The polymer 5 synthesized in Synthesis Example 5 is obtained from 10.0 g, 4,4'-(1- {4- [1- (4-hydroxyphenyl) -1-methylethyl] phenyl} ethylidene) bisphenol and 1,2. 2.25 g of esterified product with -naphthoquinone diazide-5-sulfonyl chloride (manufactured by Daito Chemix Co., Ltd .: PA-28), ε-caprolactone modified 3,4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (stock) 3.0 g of CEL2081) manufactured by Daicel Co., Ltd., 3.0 g of KBM-803 (manufactured by Shinetsu Silicone Co., Ltd.) to improve adhesion, and prevent radial striations formed on the ester film during rotary coating. For this purpose, 0.03 g of F-556 (manufactured by DIC), 1.0 g of fluorogluside, and 2.0 g of TekP-4HBPA (manufactured by Honshu Kagaku) are mixed solvents of propylene glycol monomethyl ether acetate: diethylene glycol ethyl methyl ether = 50:50. Was dissolved so as to have a solid content of 20%. This was filtered through a 0.2 μm PTFE filter to prepare a positive photosensitive resin composition.
The following evaluation was performed on the obtained photosensitive resin composition. The results obtained are shown in Table 1.

Each component in Table 1 is as follows.
(Photosensitive agent)
Photosensitizer 1: Photosensitizer represented by the following formula (B-1) (Product name PA-28 manufactured by Daito Chemix Corp.)
The Q in the formula (B-1) is represented by a hydrogen atom or the above formula (B-2), and 90% of the total Q is the above formula (B-2).
(Crosslinking agent)
Crosslinking agent 1: ε-caprolactone-modified 3', 4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (CEL2081 manufactured by Daicel Corporation))
(Silane coupling agent)
Silane Coupling Agent 1: 3-Mercaptopropyltrimethoxysilane (manufactured by Shinetsu Silicone Co., Ltd., KBM-803)
Silane coupling agent 2: 3-glycidoxypropyltrimethoxysilane (manufactured by Shinetsu Silicone Co., Ltd., KBM-403)
(Surfactant)
Surfactant 1: Fluorine-based surfactant (Megafuck F-556, manufactured by DIC Corporation)
(Additive)
Ballast material 1: Fluorogluside ballast material 2: TekP-4HBPA (manufactured by Honshu Chemical Industry Co., Ltd.)
(catalyst)
Acid generator 1: SI-110 (manufactured by Sanshin Chemical Industry Co., Ltd.)
(solvent)
Solvent 1: Propylene glycol monomethyl ether acetate Solvent 2: Diethylene glycol ethyl methyl ether

It was found that Examples 1 to 4 had higher sensitivity than Comparative Examples 1 and 2. Further, it was found that Examples 1 to 4 were superior in thermal flow resistance as compared with Comparative Example 2. Further, it was found that Examples 1 to 4 were superior in stability over time as compared with Comparative Example 1. Therefore, it was found that Examples 1 to 4 were excellent in the balance between high sensitivity, thermal flow resistance and aging stability.

Although the present invention has been described more specifically based on the above examples, these are examples of the present invention, and various configurations other than the above can be adopted.

30 Interlayer insulating film 32 Passivation film 34 Top layer wiring 40 Rewiring layer 42, 44 Insulation layer 46 Rewiring 50 UBM layer 52 Bump 100 Electronic device

Claims (9)

A structural unit having an oxetanyl group and
Structural units derived from N-substituted maleimides having a hydroxy or carboxy group,
Only including,
The structural unit having an oxetanyl group is represented by the following general formula.
(In the above general formula, n is 0, 1 or 2. R ₁ , R ₂ , R ₃ and R ₄ are each independently hydrogen or an organic group having 1 to 10 carbon atoms, and at least of these. One has an oxetane group.)
A polymer in which the structural unit derived from the N-substituted maleimide is represented by the following general formula .
(In the above general formula, X is an alkyl group having 1 to 15 carbon atoms and 6 to 14 carbon atoms substituted with one or more selected from the group consisting of a hydroxy group, a hydroxyalkyl group, a carboxy group and a carboxyalkyl group. Or a cycloalkyl group having 3 to 12 carbon atoms.) The polymer according to claim 1.
A polymer that is a polymer for forming a photosensitive resin film. The polymer according to claim 1 or 2 .
A polymer comprising the structural unit derived from N-substituted maleimide having a hydroxy group and the structural unit derived from N-substituted maleimide having the carboxy group. The polymer according to any one of claims 1 to 3 .
A polymer in which the structural unit derived from N-substituted maleimide having a hydroxy group is represented by the following general formula.
(In the general formula, _{R 5} represents a hydroxy group.) The polymer according to any one of claims 1 to 4 .
A polymer further comprising a maleimide-derived structural unit represented by the following general formula.
(R ₉ in the above general formula is an alkyl group having 1 to 15 carbon atoms substituted with one or more carboxy groups.) The polymer according to any one of claims 1 to 5 .
The structural unit derived from N-substituted maleimide is a polymer further comprising a structural unit derived from maleimide represented by the following general formula.
(R ₆ in the above general formula is a hydrogen, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 8 carbon atoms.) The polymer according to any one of claims 1 to 6 .
A polymer in which the molar ratio of structural units derived from the N-substituted maleimide in the polymer is 10 or more and 90 or less with respect to 100 of the entire polymer. A photosensitive resin composition comprising the polymer according to any one of claims 1 to 7 . An electronic device comprising a cured product of a photosensitive resin film comprising the photosensitive resin composition according to claim 8 .