WO2023054381A1

WO2023054381A1 - Photosensitive resin composition, method for producing electronic device, electronic device and light device

Info

Publication number: WO2023054381A1
Application number: PCT/JP2022/035981
Authority: WO
Inventors: 和紀井上; 敏彦片山; 広道杉山
Original assignee: 住友ベークライト株式会社
Priority date: 2021-09-30
Filing date: 2022-09-27
Publication date: 2023-04-06
Also published as: TW202330724A; JP2024012299A; JPWO2023054381A1

Abstract

The present invention provides: a photosensitive resin composition which contains (A) a polyimide resin, (B) a multifunctional (meth)acrylate compound, (C) a sensitizing agent and (D) a polymerization inhibitor, wherein the polyimide resin (A) comprises a structure that is represented by general formula (a) (in general formula (a), X represents a divalent organic group, and Y represents a tetravalent organic group); an electronic device which is provided with an insulating layer that is formed of this photosensitive resin composition; and a light device which is provided with an insulating layer that is formed of this photosensitive resin composition.

Description

Photosensitive resin composition, method for manufacturing electronic device, electronic device and optical device

The present invention relates to a photosensitive resin composition, an electronic device manufacturing method, an electronic device, and an optical device.

In the electrical and electronic fields, photosensitive resin compositions containing polyamide resins and/or polyimide resins are sometimes used to form cured films such as insulating layers. Therefore, photosensitive resin compositions containing polyamide resins and/or polyimide resins have been investigated.

By way of example, US Pat. No. 5,300,002 discloses at least one fully imidized polyimide polymer having a weight average molecular weight ranging from about 20,000 Daltons to about 70,000 Daltons; at least one solubility-switching compound; at least one A photosensitive composition is described which comprises a photoinitiator; and at least one solvent and is capable of forming a film exhibiting a dissolution rate of greater than about 0.15 μm/sec when cyclopentanone is used as a developer. ing.

Patent Documents

2 and 3 also describe photosensitive resin compositions containing polyamide resins and/or polyimide resins.

WO2016/172092 WO2007/047384 JP 2018-070829 A

When forming a cured film in an electronic device using a photosensitive resin composition, a curing treatment by heat is usually performed. Specifically, first, a photosensitive resin composition is coated on a substrate to form a film, and the film is patterned by exposure and development. Then, a cured film is formed by heat-treating the patterned film.
As a result of studies by the present inventors, there is room for further improvement in the elongation of the cured film and the focus margin in the exposure process and the development process as described above.

The present invention was made in view of such circumstances. One of the objects of the present invention is to provide a photosensitive resin composition having moderate elongation and a large focus margin.

The inventors have completed the invention provided below and solved the above problems.

According to the invention,
a polyimide resin (A);
a polyfunctional (meth)acrylate compound (B);
a photosensitizer (C);
a polymerization inhibitor (D);
A photosensitive resin composition comprising
The polyimide resin (A) includes a structure represented by the following general formula (a),

In general formula (a),
X is a divalent organic group,
Y is a tetravalent organic group,
A photosensitive resin composition is provided.

Moreover, according to the present invention,
A film forming step of forming a photosensitive resin film on a substrate using the photosensitive resin composition;
an exposure step of exposing the photosensitive resin film;
a developing step of developing the exposed photosensitive resin film;
A method of manufacturing an electronic device is provided, comprising:

Moreover, according to the present invention,
An electronic device comprising a cured film of the above photosensitive resin composition is provided.

Moreover, according to the present invention,
a light emitting element;
wiring electrically connected to the light emitting element;
and an insulating film covering the wiring,
An optical device is provided, wherein the insulating film is a cured film of the above photosensitive resin composition.

According to the present invention, a photosensitive resin composition is provided that has moderate elongation and a large focus margin.

It is a longitudinal section showing an example of composition of an electronic device concerning this embodiment. FIG. 2 is a partially enlarged view of a region surrounded by a dashed line in FIG. 1; 1. It is process drawing which shows the method of manufacturing the electronic device shown in FIG. 1. It is a figure for demonstrating the method to manufacture the electronic device shown in FIG. 1. It is a figure for demonstrating the method to manufacture the electronic device shown in FIG. 1. It is a figure for demonstrating the method to manufacture the electronic device shown in FIG. It is a figure for demonstrating the method to manufacture the optical device which concerns on this embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
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 order to avoid complication, (i) when there are a plurality of the same components in the same drawing, only one of them is given a reference numeral and not all of them, and (ii) in particular the figure 2 onward, the same constituent elements as those in FIG. 1 may not be denoted by reference numerals.
All drawings are for illustration purposes only. The shape and dimensional ratio of each member in the drawings do not necessarily correspond to the actual article.

In this specification, the term "substantially" means that it includes a range that takes into account manufacturing tolerances, assembly variations, and the like, unless otherwise explicitly stated.
In this specification, the notation "X to Y" in the description of numerical ranges means X or more and Y or less, unless otherwise specified. For example, "1 to 5% by mass" means "1% by mass or more and 5% by mass or less".

In the description of a group (atomic group) in the present specification, a description without indicating whether it is substituted or unsubstituted includes both those having no substituent and those having a substituent. For example, the term “alkyl group” includes not only alkyl groups without substituents (unsubstituted alkyl groups) but also alkyl groups with substituents (substituted alkyl groups).
The notation "(meth)acryl" used herein represents a concept that includes both acryl and methacryl. The same applies to similar notations such as "(meth)acrylate".
The term "organic group" as used herein means an atomic group obtained by removing one or more hydrogen atoms from an organic compound, unless otherwise specified. For example, a "monovalent organic group" represents an atomic group obtained by removing one hydrogen atom from an arbitrary organic compound.
The term "electronic device" as used herein refers to elements to which electronic engineering technology is applied, such as semiconductor chips, semiconductor elements, printed wiring boards, electric circuit display devices, information communication terminals, light-emitting diodes, physical batteries, and chemical batteries. , devices, final products, etc.

<Photosensitive resin composition>
The photosensitive resin composition of this embodiment contains a polyimide resin (A), a polyfunctional (meth)acrylate compound (B), a photosensitive agent (C), and a polymerization inhibitor (D). In this embodiment, the polyimide resin (A) is a closed-ring polyimide resin containing a closed-ring imide structure represented by the following general formula (a).

In general formula (a), X is a divalent organic group and Y is a tetravalent organic group.

Many conventional polyamide/polyimide-based photosensitive resin compositions contain polyamide but do not contain polyimide before use (before forming a cured film). That is, conventionally, a photosensitive resin composition containing polyamide is used to form a film on a substrate, and the film is typically heated to ring-close the polyamide to form polyimide.
However, in this case, the film shrinks due to the ring-closure reaction and the accompanying dehydration, and it is sometimes difficult to obtain a cured film with good flatness.

On the other hand, the photosensitive resin composition of the present embodiment already contains the polyimide resin (A) before use (before forming the cured film). In addition, in this embodiment, the polymerization reaction of the polyfunctional (meth)acrylate compound (B) is employed as the curing mechanism (this polymerization reaction does not involve dehydration in principle). From these matters, by forming a cured film using the photosensitive resin composition of the present embodiment, it is possible to form a cured film with small shrinkage due to heating and good flatness. In particular, it is possible to form a cured film with good flatness even on a substrate having steps.

Moreover, by using the photosensitive resin composition of the present embodiment, it is easy to form a cured film having good heat resistance and good mechanical properties (for example, tensile elongation).
Cured films in electronic devices are often required to have high heat resistance and good mechanical properties. Conventionally, however, when a resin is designed to be rigid in order to improve its heat resistance, the flexibility of the resin may be lost and mechanical properties such as elongation may be degraded.
Although the details are unknown, in the photosensitive resin composition of the present embodiment, the polyfunctional (meth)acrylate compound (B) is intricately entangled with the polyimide resin (A) during curing (polymerization). , it is thought that a cured film different from conventional cured films is formed. This "entangled structure of polyimide resin and polyfunctional (meth)acrylate" is considered to be related to good heat resistance and good mechanical properties.

When the polyfunctional (meth)acrylate compound (B) is used, the extensibility of the obtained photosensitive resin composition is improved as described above, but on the other hand, swelling of the cured portion and non-uniformity of the unexposed portion Inadequate dissolution (bridge) due to excessive dissolution, and phenomenon (foot) in which the unexposed area is not completely dissolved and remains may occur. Due to the occurrence of these defects, there is a possibility that a sufficient focus margin cannot be obtained.
Here, as a result of investigation by the present inventors, it was found that both good elongation and good focus margin can be achieved by using the photosensitizer (C) and the polymerization inhibitor (D). By using the photosensitive agent (C) in the photosensitive resin composition of the present embodiment, the curability of the exposed area is improved, and the generation of bridges in the development process can be suppressed while maintaining good mechanical properties. . In the photosensitive resin composition of the present embodiment, by using a polymerization inhibitor (D), the solubility of the unexposed area is improved, and the generation of feet in the development process is suppressed while maintaining good mechanical properties. can do. By highly suppressing these bridges and feet, the focus margin of the photosensitive resin composition can be increased.
In other words, by using the photosensitive agent (C) and the polymerization inhibitor (D) at the same time and highly controlling the ratio thereof, the cured film of the photosensitive resin composition of the present embodiment has good elongation. and a good focus margin can be achieved at the same time.

From the above matters, the photosensitive resin composition of the present embodiment is preferably used for forming insulating layers in electronic devices or optical devices.

The description of the components that the photosensitive resin composition of the present embodiment can contain and the properties and physical properties of the photosensitive resin composition of the present embodiment will be continued.

(Polyimide resin (A))
The photosensitive resin composition of this embodiment contains a polyimide resin (A) containing a structural unit represented by general formula (a).

As already mentioned, the photosensitive resin composition of the present embodiment tends to shrink less due to curing (heating) by using a polyimide resin containing a closed ring imide structure represented by the general formula (a) before curing. There is

When the number of moles of imide groups contained in the polyimide resin (A) is IM and the number of moles of amide groups contained in the polyimide resin (A) is AM, {IM/(IM+AM)}×100(%) The imidization ratio represented by is preferably 90% or more, more preferably 95% or more, and still more preferably 98% or more. In short, it is preferable that the polyimide resin (A) is a resin having few or no ring-opening amide structures and many ring-closing imide structures. By using such a polyimide, shrinkage due to heating can be further suppressed, and a cured film with better flatness can be formed.
The imidization rate can be known, for example, from the area of the peak corresponding to the amide group or the area of the peak corresponding to the imide group in the NMR spectrum. As another example, the imidization rate can be known from the area of the peak corresponding to the amide group, the area of the peak corresponding to the imide group, and the like in the infrared absorption spectrum.

The polyimide resin (A) preferably contains a polyimide resin containing a fluorine atom. The present inventors have found that polyimide resins containing fluorine atoms tend to have better solubility in organic solvents than polyimide resins containing no fluorine atoms. Therefore, by using a polyimide resin containing a fluorine atom, it is easy to make the property of the photosensitive resin composition varnish-like.
The amount (mass ratio) of fluorine atoms in the polyimide resin containing fluorine atoms is, for example, 1 to 30% by mass, preferably 3 to 28% by mass, more preferably 5 to 25% by mass. A certain amount of fluorine atoms contained in the polyimide resin facilitates obtaining sufficient organic solvent solubility. On the other hand, from the viewpoint of balance with other performances, it is preferable that the amount of fluorine atoms is not too large.

By designing various ends of the polyimide resin (A), for example, the mechanical properties (tensile elongation, etc.) of the cured product can be further improved.

As an example, the polyimide resin (A) preferably has a group at its end that can react with an epoxy group to form a bond. Such groups include acid anhydride groups, hydroxy groups, amino groups, carboxy groups, and the like.

Preferably, the polyimide resin (A) has an acid anhydride group at its end. In the photosensitive resin composition of this embodiment, the acid anhydride group and the epoxy group are sufficiently easy to form a bond.
The acid anhydride group is preferably a group having a cyclic acid anhydride skeleton. The "cyclic structure" herein is preferably a 5- or 6-membered ring, more preferably a 5-membered ring.

Here, in the structural unit represented by general formula (a) that constitutes the polyimide resin (A), X is a divalent organic group and Y is a tetravalent organic group.

The divalent organic group of X and/or the tetravalent organic group of Y preferably contains an aromatic ring structure, more preferably a benzene ring structure. This tends to further increase the heat resistance.
The divalent organic group of X and/or the tetravalent organic group of Y preferably has a structure in which 2 to 6 benzene rings are linked via a single bond or a divalent linking group. Examples of the divalent linking group here include an alkylene group, a fluorinated alkylene group, an ether group, and the like. Alkylene groups and fluorinated alkylene groups may be linear or branched.
The number of carbon atoms in the divalent organic group of X is, for example, 6-30.
The number of carbon atoms in the tetravalent organic group of Y is, for example, 6-20.
Each of the two imide rings in general formula (a) is preferably a five-membered ring.

The polyimide resin (A) preferably contains a polyimide resin containing a fluorine atom. This tends to increase the solubility in organic solvents.
Moreover, from the viewpoint of further improving the organic solvent solubility, both X and Y are preferably fluorine atom-containing groups.

The polyimide resin (A) more preferably contains a structural unit represented by the following general formula (aa).

In the general formula (aa),
Y' represents a single bond or an alkylene group,
X has the same definition as X in formula (a).
The alkylene group of Y' may be linear or branched. Some or all of the hydrogen atoms in the alkylene group of Y' are preferably substituted with fluorine atoms. The number of carbon atoms in the alkylene group of Y' is, for example, 1-6, preferably 1-4, more preferably 1-3.

The polyimide resin (A) is typically prepared by (i) first reacting (condensation polymerization) a diamine and an acid dianhydride to synthesize a polyamide, and (ii) then imidating the polyamide (ring closure reacting), and (iii) introducing a desired functional group to the terminal of the polymer as necessary. Specific reaction conditions can be referred to Examples described later, the description of Patent Document 1 described above, and the like.

In the finally obtained polyimide resin (A), the diamine is incorporated into the polymer as the divalent organic group X in general formula (a). Also, the acid dianhydride is incorporated into the polymer as the tetravalent organic group Y in the general formula (a).
In synthesizing the polyimide resin (A), one or two or more diamines can be used, and one or two or more acid dianhydrides can be used.

Raw material diamines include, for example, 3,4′-diaminodiphenyl ether (3,4′-ODA), 4,4′-diamino-2,2′-bis(trifluoromethyl)biphenyl (TFMB), 3,3 ',5,5'-tetramethylbenzidine, 2,3,5,6-tetramethyl-1,4-phenylenediamine, 3,3'-diaminodiphenylsulfone, 3,3'dimethylbenzidine, 3,3'- Bis(trifluoromethyl)benzidine, 2,2'-bis(p-aminophenyl)hexafluoropropane, bis(trifluoromethoxy)benzidine (TFMOB), 2,2'-bis(pentafluoroethoxy)benzidine (TFEOB) , 2,2′-trifluoromethyl-4,4′-oxydianiline (OBABTF), 2-phenyl-2-trifluoromethyl-bis(p-aminophenyl)methane, 2-phenyl-2-trifluoromethyl -bis(m-aminophenyl)methane, 2,2'-bis(2-heptafluoroisopropoxy-tetrafluoroethoxy)benzidine (DFPOB), 2,2-bis(m-aminophenyl)hexafluoropropane (6- FmDA), 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane, 3,6-bis(trifluoromethyl)-1,4-diaminobenzene (2TFMPDA), 1-(3,5- diaminophenyl)-2,2-bis(trifluoromethyl)-3,3,4,4,5,5,5-heptafluoropentane, 3,5-diaminobenzotrifluoride (3,5-DABTF), 3 ,5-diamino-5-(pentafluoroethyl)benzene, 3,5-diamino-5-(heptafluoropropyl)benzene, 2,2′-dimethylbenzidine (DMBZ), 2,2′,6,6′- tetramethylbenzidine (TMBZ), 3,6-diamino-9,9-bis(trifluoromethyl)xanthene (6FCDAM), 3,6-diamino-9-trifluoromethyl-9-phenylxanthene (3FCDAM), 3, 6-diamino-9,9-diphenylxanthene

Examples of acid dianhydrides used as raw materials include pyromellitic anhydride (PMDA), diphenyl ether-3,3′,4,4′-tetracarboxylic dianhydride (ODPA), benzophenone-3,3′, 4,4'-tetracarboxylic dianhydride (BTDA), biphenyl-3,3',4,4'-tetracarboxylic dianhydride (BPDA), diphenylsulfone-3,3',4,4'- Tetracarboxylic dianhydride (DSDA), diphenylmethane-3,3',4,4'-tetracarboxylic dianhydride, 2,2-bis(3,4-phthalic anhydride) propane, 2,2-bis (3,4-Phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane (6FDA) and the like can be mentioned. Of course, acid dianhydrides that can be used are not limited to these. One or two or more acid dianhydrides can be used.

The usage ratio of the diamine and the acid dianhydride is basically 1:1 in terms of molar ratio. However, one may be used in excess to obtain the desired terminal structure. Specifically, by using an excessive amount of diamine, the ends (both ends) of the polyimide resin (A) tend to become amino groups. On the other hand, when the acid dianhydride is excessively used, the ends (both ends) of the polyimide resin (A) tend to become acid anhydride groups. As described above, in the present embodiment, the polyimide resin (A) preferably has an acid anhydride group at its terminal. Therefore, in the present embodiment, it is preferable to use an excess amount of acid dianhydride when synthesizing the polyimide resin (A).

The terminal amino groups and/or acid anhydride groups of the polyimide obtained by condensation polymerization may be reacted with some kind of reagent so that the polyimide terminals have desired functional groups.

The weight average molecular weight of the polyimide resin (A) is, for example, 5,000 to 100,000, preferably 7,000 to 75,000, more preferably 10,000 to 50,000. When the weight average molecular weight of the polyimide resin (A) is large to some extent, for example, sufficient heat resistance of the cured film can be obtained. Moreover, when the weight average molecular weight of the polyimide resin (A) is not too large, it becomes easier to dissolve the polyimide resin (A) in the organic solvent.
The weight average molecular weight can usually be determined by gel permeation chromatography (GPC) using polystyrene as a standard substance.

(Polyfunctional (meth)acrylate compound (B))
The photosensitive resin composition of this embodiment contains a polyfunctional (meth)acrylate compound (B). As the polyfunctional (meth)acrylate compound (B), those having two or more (meth)acryloyl groups in one molecule can be mentioned without particular limitation.

From the viewpoint of realizing the above-mentioned "entangled structure of polyimide resin and polyfunctional (meth)acrylate" and from the viewpoint of obtaining a cured film that is strong and has good chemical resistance, the polyfunctional (meth)acrylate compound (B) is , is preferably trifunctional or higher. Although there is no particular upper limit for the number of functional groups of the polyfunctional (meth)acrylate compound (B), 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 (B) 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 the polyfunctional (meth)acrylate compound (B) 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 (B) preferably contains a 3- to 4-functional (meth)acrylate compound (B1).

As an example, the polyfunctional (meth)acrylate compound (B) preferably contains a pentafunctional or higher (meth)acrylate compound (B2).

As an example, the polyfunctional (meth)acrylate compound (B) can contain a compound represented by the following general formula (b). 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 the polyfunctional (meth)acrylate compound (B) include the following. Of course, polyfunctional (meth)acrylate compounds (B) 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 (B), or may contain two or more polyfunctional (meth)acrylate compounds (B). In the latter case, it is preferable to use together a polyfunctional (meth)acrylate compound (B) having a different number of functional groups. By using polyfunctional (meth)acrylate compounds (B) with different numbers of functional groups together, a more complex "entangled structure of polyimide and polyfunctional (meth)acrylate" can be created, resulting in better heat resistance and mechanical properties. It is considered possible.
Incidentally, among commercially available polyfunctional (meth)acrylate compounds (B), there are also mixtures of (meth)acrylates having different numbers of functional groups.

The amount of the polyfunctional (meth)acrylate compound (B) with respect to 100 parts by mass of the polyimide resin (A) is, for example, 25 to 150 parts by mass, preferably 50 to 120 parts by mass, more preferably 70 to 100 parts by mass, more preferably 80 to 95 parts by mass.
The amount of the polyfunctional (meth)acrylate compound (B) used is not particularly limited, but one or more of the various properties can be enhanced by appropriately adjusting the amount used as described above. As described above, in the photosensitive resin composition of the present embodiment, it is considered that "the entangled structure of the polyimide having a cyclic structure and the polyfunctional (meth)acrylate" is formed by curing, but the polyimide resin (A By appropriately adjusting the amount of the polyfunctional (meth) acrylate compound (B) for ), the polyimide resin (A) and the polyfunctional (meth) acrylate compound (B) are sufficiently entangled, and are not involved in the entanglement. It is believed that there are fewer redundant components, resulting in better performance.

(Photosensitizer (C))
The photosensitive resin composition of this embodiment contains a photosensitive agent (C). The photosensitive agent (C) is not particularly limited as long as it can generate active species by light and cure the photosensitive resin composition.

The photosensitizer (C) preferably contains a photoradical generator. A photoradical generator is particularly effective for polymerizing the polyfunctional (meth)acrylate compound (B).

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, benzophenone compounds such as 4,4′-bis(dimethylamino)benzophenone and 2-carboxybenzophenone; benzoin compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether; thioxanthone, 2-ethylthioxanthone, Thioxanthone compounds such as 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(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- Oxadiazole, 2-trichloromethyl-5-[β-(2′-benzofuryl)vinyl]-1,3,4-oxadiazole, 4-oxadiazole, 2-trichloromethyl-5-furyl-1, Halomethylated oxadiazole compounds such as 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′-tetraphenyl-1,2′-biimidazole compounds such as 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; Titanocene compounds such as (η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium; acyl compounds such as acylphosphine oxide phosphine compounds; benzoic acid ester compounds such as p-dimethylaminobenzoic acid and p-diethylaminobenzoic acid; acridine compounds such as 9-phenylacridine; Among these, oxime ester compounds can be preferably used.

The photosensitive resin composition may contain only 1 type of photosensitive agents (C), and may contain 2 or more types.
The content of the photosensitive agent (C) is, for example, 5 parts by mass or more and 30 parts by mass or less, preferably 10 parts by mass or more and 25 parts by mass or less with respect to 100 parts by mass of the polyimide resin (A).

(Polymerization inhibitor (D))
The photosensitive resin composition of this embodiment contains a polymerization inhibitor (D).
In this embodiment, the polymerization inhibitor (D) includes, for example, hindered phenol compounds, hindered amine compounds, N-oxyl compounds and thioether compounds. Among these, one or more selected from hindered phenol-based compounds, hindered amine-based compounds, and N-oxyl compounds are preferably included from the viewpoint of improving the solubility of unexposed areas.

Examples of hindered phenol compounds include 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H, 3H,5H)-trione, 4,4′,4″-(1-methylpropanyl-3-ylidene)tris(6-tert-butyl-m-cresol), 6,6′-di-tert-butyl- 4,4′-butylidenedi-m-cresol, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010), 3,9-bis{2-[3- (3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,3, 5-tris(3,5-di-tert-butyl-4-hydroxyphenylmethyl)-2,4,6-trimethylbenzene, 2,2′-thiodiethylbis[3-(3,5-di-tert- butyl-4-hydroxyphenyl)propionate] (Irganox 1035), N,N'-(1,6-hexanediyl)bis[3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanamide], bis[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionic acid][ethylenebis(oxyethylene)], 1,6-hexanediol bis[3-(3,5-di-tert -butyl-4-hydroxyphenyl)propionate], 2,6-di-tert-butyl-4-cresol, 2,4-bis[(dodecylthio)methyl]-6-methylphenol (Irganox 1726), 2,4-bis and (octylthiomethyl)-6-methylphenol (Irganox 1520L), etc. These may be used alone or in combination of two or more.

Examples of hindered amine compounds include tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate, tetrakis(2,2,6,6- Tetramethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate, 1,2,3,4-butanetetracarboxylic acid and 1,2,2,6,6-pentamethyl-4-piperidinol and 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane mixed ester, 1,2,3,4-butane Tetracarboxylic acid with 2,2,6,6-tetramethyl-4-piperidinol and 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5 .5] mixed esters with undecane, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1-Undecanoxy-2,2,6,6-tetramethylpiperidin-4-yl) carbonate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, 2,2,6,6-tetramethyl -4-piperidyl methacrylate, a reaction product of 2,2,6,6-tetramethylpiperidin-4-ylhexadecanoate and 2,2,6,6-tetramethylpiperidin-4-yloctadecanoate, etc. is mentioned. These may be used individually by 1 type, or may use 2 or more types together.

Examples of N-oxyl compounds include 4-benzoyloxy-2,2,6,6-tetramethylpiperidinooxyl (4-benzoyloxy TEMPO), N-nitrosodiphenylamine, N-nitroso-N-phenylhydroxylamine. , 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), 4-hydroxy-2,2,6,6-tetramethylpiperidi-1-oxyl free radical (4-hydroxy TEMPO), sebacin acid bis(2,2,6,6-tetramethyl-4-piperidyl-1-oxyl) (bis sebacate TEMPO); These may be used individually by 1 type, or may use 2 or more types together.

The thioether compounds include 2,2-bis{[3-(dodecylthio)-1-oxopropoxy]methyl}propane-1,3-diylbis[3-(dodecylthio)propionate], di(tridecyl)-3 , 3′-thiodipropionate and the like. These may be used individually by 1 type, or may use 2 or more types together.

In the photosensitive resin composition of the present embodiment, the content of the polymerization inhibitor (D) with respect to 100 parts by mass of the polyimide resin (A) is preferably 0.1 parts by mass or more and 5 parts by mass or less, more preferably 1 It is at least 3 parts by mass and no more than 3 parts by mass. If the content of the polymerization inhibitor (D) is within the above range, the solubility of the unexposed area is improved, and the phenomenon that the unexposed area in the development process is not completely dissolved and remains while maintaining good mechanical properties (foot ) can be suppressed.

Further, in the photosensitive resin composition of the present embodiment, the content of the polymerization inhibitor (D) with respect to 100 parts by mass of the photosensitive agent (C) is preferably 1 part by mass or more and 30 parts by mass or less, more preferably 5 parts by mass. It is more than 20 parts by mass and less than 20 parts by mass. If the content of the polymerization inhibitor (D) with respect to 100 parts by mass of the photosensitive agent (C) is within the above range, the cured film of the photosensitive resin composition of the present embodiment has good elongation and a good focus margin. It is possible to achieve both.

(Thermal radical generator (E))
The photosensitive resin composition of the present embodiment preferably contains a thermal radical generator (E). By using the thermal radical generator (E), 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 generator (E) further accelerates the polymerization reaction of the polyfunctional (meth)acrylate compound (B).

The thermal radical generator (E) 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 the thermal radical generator (E) is used, only one thermal radical generator (E) may be used, or two or more thermal radical generators (E) may be used.
When the thermal radical generator (E) is used, the amount thereof is preferably 0.1 parts by mass or more and 30 parts by mass or less, more preferably 1 part by mass or more and 20 parts by mass, relative to 100 parts by mass of the polyimide resin (A). It is below.

(Crosslinking agent (F))
The photosensitive resin composition of the present embodiment preferably contains a cross-linking agent (F). By using the cross-linking agent (F), for example, the cross-linking agent (F) reacts with other components contained in the photosensitive resin composition, or the cross-linking agent (F) is polymerized with each other, and the cross-linking agent (F) becomes closely entangled with the photosensitive resin composition. This is thought to improve the chemical resistance and elongation of the resin film made of the cured product of the photosensitive resin composition.

The cross-linking agent (F) preferably has one epoxy-containing group at one end of the molecule and one (meth)acryloyl group at the other end of the molecule. By providing this configuration, the number of unreacted functional groups is reduced, and as a result, the chemical resistance and elongation of the resin film made of the cured product of the photosensitive resin composition are improved.

In the present embodiment, the "epoxy-containing group" refers to a substituent having a three-membered ether oxacyclopropane (oxirane) in its structural formula. Specific examples thereof include an epoxy group, a glycidyl group, a glycidyl ether group, and one or more hydrogen atoms in an organic group to an epoxy group, a glycidyl group, or a glycidyl ether group (a group obtained by removing hydrogen from the OH group of glycidol). Substituted groups may be mentioned, and specific examples include 1,2-epoxycyclohexyl group and the like. Although the organic group is not particularly limited, examples 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 and hexyl. alkyl groups such as group, heptyl group, octyl group, nonyl group and decyl group; alkenyl groups such as allyl group, pentenyl group and vinyl group; alkynyl groups such as ethynyl group; alkylidene groups such as methylidene group and ethylidene group; aryl groups such as , naphthyl and anthracenyl groups; aralkyl groups such as benzyl and phenethyl groups; alkaryl groups such as tolyl and xylyl groups; or cycloalkyl groups such as adamantyl, cyclopentyl, cyclohexyl and cyclooctyl groups is mentioned.

The cross-linking agent (F) preferably contains a compound represented by general formula (1).

In general formula (1),
X ₁ represents a (meth)acryloyl group. _X2 represents a glycidyl group, a glycidyl ether group, an epoxy group or a 1,2-epoxycyclohexyl group as an epoxy-containing group. Further, n represents an integer of 1-10.

By selecting X ₂ from the above functional groups, the reactivity between the cross-linking agent (F) and other components contained in the photosensitive resin composition or the cross-linking agent (F) is improved, and the photosensitive resin composition It is preferable because the chemical resistance and elongation of the resin film made of the cured product are improved.

Further, when n is within the range of 1 to 10, the elongation rate of the resin film made of the cured product of the photosensitive resin composition becomes more suitable, which is preferable.

In the cross-linking agent (F), it is preferable that one or more compounds selected from compounds represented by any one of the following chemical formulas (2) to (4) be included as the compound satisfying the general formula (1). By containing one or more compounds selected from any one of the following chemical formulas (2) to (4), the chemical resistance and elongation of the resin film made of the cured product of the photosensitive resin composition are increased. You can have both in balance.

The content of the cross-linking agent (F) is, for example, 0.1 parts by mass or more, preferably 0.5 parts by mass or more, more preferably 1 part by mass or more with respect to 100 parts by mass of the polyimide resin (A). . When the content of the cross-linking agent (F) is 0.1 parts by mass or more, the cured product of the photosensitive resin composition can have high chemical resistance.
The content of the cross-linking agent (F) is, for example, 30 parts by mass or less, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, relative to 100 parts by mass of the polyimide resin (A). When the content of the cross-linking agent (F) is 30 parts by mass or less, the ratio of the polyimide resin (A) in the photosensitive resin composition is maintained, and the elongation of the cured product of the photosensitive resin composition becomes good. In addition, the adhesion between the photosensitive resin composition and the substrate is sufficiently improved.

The photosensitive resin composition of the present embodiment may contain only one type of cross-linking agent (F), or may contain two or more types.

(Silane coupling agent (G))
The photosensitive resin composition of this embodiment preferably contains a silane coupling agent (G). By using the silane coupling agent (G), for example, the adhesion between the substrate and the cured film can be further enhanced.

Examples of the silane coupling agent (G) include 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, vinyl group-containing Silane coupling agents such as silane coupling agents, ureido group-containing silane coupling agents, sulfide group-containing silane coupling agents, and silane coupling agents 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 presumed that the cyclic anhydride structure readily reacts with the main chain, side chains and/or terminals of the polyimide resin (A), resulting in a particularly good effect of improving adhesion.

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

(Curing catalyst (H))
The photosensitive resin composition of the present embodiment preferably contains a curing catalyst (H). This curing catalyst (H) functions to accelerate the reaction of the cross-linking agent (F). By using the curing catalyst (H), the reaction involving the cross-linking agent (F) can proceed sufficiently, and for example, the tensile elongation of the cured film can be further improved.

The curing catalyst (H) includes compounds known as curing catalysts for epoxy resins (often called curing accelerators). For example, diazabicycloalkenes such as 1,8-diazabicyclo[5,4,0]undecene-7 and derivatives thereof; amine compounds such as tributylamine and benzyldimethylamine; imidazole compounds such as 2-methylimidazole; triphenyl Organic phosphines such as phosphine and methyldiphenylphosphine; tetra-substituted phosphonium salts such as phosphonium/tetranaphthyloxyborate and tetraphenylphosphonium/4,4'-sulfonyldiphenolate; and triphenylphosphine obtained by adducting benzoquinone. Among them, organic phosphines are preferred.

When the curing catalyst (H) is used, its amount is, for example, 1 to 80 parts by mass, preferably 2 to 50 parts by mass, more preferably 3 to 30 parts by mass with respect to 100 parts by mass of the cross-linking agent (F). .

(Surfactant (I))
The photosensitive resin composition of the present embodiment preferably contains surfactant (I). This can further improve the applicability of the photosensitive resin composition and the flatness of the film.
Surfactants (I) 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.

Surfactant (I) 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 adhesive 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 commercially available products that can be used as the surfactant (I) include F-251, F-253, F-281, F-430, F-477, and F-251, F-253, F-281, F-430, F-477, and F-251, F-253, F-281, F-430, and F-477, manufactured by DIC Corporation. -551, 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 Fluorine-containing oligomer structure surfactants such as, fluorine-containing nonionic surfactants such as Ftergent 250 and Ftergent 251 manufactured by Neos Co., Ltd., SILFOAM (registered trademark) series manufactured by Wacker Chemie (for example, and silicone surfactants such as 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 the present embodiment contains surfactant (I), it can contain one or more surfactants.
When the photosensitive resin composition of the present embodiment contains the surfactant (I), the amount thereof is, when the content of the polyimide resin (A) is 100 parts by mass, for example 0.001 to 1 part by mass, preferably is 0.005 to 0.5 parts by mass.

(Solvent (J)/property of composition)
The photosensitive resin composition of this embodiment preferably contains a solvent (J). Thereby, a photosensitive resin film can be easily formed on a substrate (particularly, a substrate having a step) by a coating method.
Solvent (J) 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 the solvent (J), 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 the polyimide resin (A) and the polyfunctional (meth)acrylate compound (B) are dissolved in the solvent (J). composition. 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. Further, since the polyimide resin (A) and the polyfunctional (meth)acrylate compound (B) are "dissolved" in the solvent (J), a homogeneous cured film can be obtained.

When the solvent (J) 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 resin (A) and the polyfunctional (meth)acrylate compound (B) in the entire composition is preferably 20 to 50% by mass. By using a relatively large amount of polyimide resin (A) and polyfunctional (meth)acrylate compound (B), 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. Such components include, for example, water, fillers such as silica, sensitizers, film-forming agents, and the like.

<Electronic device manufacturing method, electronic device>
The method for manufacturing an electronic device according to this embodiment includes:
A film forming step of forming a photosensitive resin film on a substrate using the photosensitive resin composition described above;
an exposure step of exposing the photosensitive resin film;
a developing step of developing the exposed photosensitive resin film;
including.
Moreover, it is preferable that the method for manufacturing an electronic device of the present embodiment includes a thermosetting step of heating and curing the exposed photosensitive resin film after the above-described developing step. Thereby, a cured film having sufficient heat resistance can be obtained.
As described above, an electronic device provided with a cured film of the photosensitive resin composition of the present embodiment can be manufactured.

The method for manufacturing the electronic device of the present embodiment, the structure of the electronic device including the cured product of the photosensitive resin composition of the present embodiment, and the like will be described below in more detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing an example of the electronic device of this embodiment. Moreover, FIG. 2 is a partially enlarged view of a region surrounded by a dashed line in FIG.
In the following description, the upper side in FIG. 1 is called "upper", and the lower side is called "lower".

The electronic device 1 shown in FIG. 1 has a so-called package-on-package structure including a through electrode substrate 2 and a semiconductor package 3 mounted thereon.

The through electrode substrate 2 includes an insulating layer 21 , a plurality of through wirings 221 penetrating from the upper surface to the lower surface of the insulating layer 21 , a semiconductor chip 23 embedded inside the insulating layer 21 , and provided on the lower surface of the insulating layer 21 . an upper wiring layer 25 provided on the upper surface of the insulating layer 21; and solder bumps 26 provided on the lower surface of the lower wiring layer 24. As shown in FIG.

The semiconductor package 3 includes a package substrate 31, a semiconductor chip 32 mounted on the package substrate 31, bonding wires 33 electrically connecting the semiconductor chip 32 and the package substrate 31, and the semiconductor chip 32 and the bonding wires 33. It has an embedded sealing layer 34 and solder bumps 35 provided on the lower surface of the package substrate 31 .

A semiconductor package 3 is laminated on the through electrode substrate 2 . Thereby, the solder bumps 35 of the semiconductor package 3 and the upper wiring layers 25 of the through electrode substrate 2 are electrically connected.

In such an electronic device 1, since it is not necessary to use a thick substrate such as an organic substrate including a core layer in the through electrode substrate 2, the height can be easily reduced. Therefore, it is possible to contribute to the miniaturization of electronic equipment incorporating the electronic device 1 .

Also, since the through electrode substrate 2 and the semiconductor package 3 having different semiconductor chips are stacked, the mounting density per unit area can be increased. Therefore, it is possible to achieve both miniaturization and high performance.

The through electrode substrate 2 and the semiconductor package 3 will be further detailed below.
The lower wiring layer 24 and the upper wiring layer 25 provided in the through electrode substrate 2 shown in FIG. 2 each include an insulating layer, a wiring layer, a through wiring, and the like. As a result, the lower wiring layer 24 and the upper wiring layer 25 include wiring inside and on the surface, and are electrically connected to each other through the through wiring 221 penetrating the insulating layer 21 .

A wiring layer included in the lower wiring layer 24 is connected to the semiconductor chip 23 and the solder bumps 26 . Therefore, the lower wiring layer 24 functions as a rewiring layer for the semiconductor chip 23 and the solder bumps 26 function as external terminals of the semiconductor chip 23 .

The through wiring 221 shown in FIG. 2 is provided so as to penetrate the insulating layer 21 as described above. As a result, the lower wiring layer 24 and the upper wiring layer 25 are electrically connected, and the through electrode substrate 2 and the semiconductor package 3 can be stacked. can.

A wiring layer 253 included in the upper wiring layer 25 shown in FIG. Therefore, the upper wiring layer 25 is electrically connected to the semiconductor chip 23, functions as a rewiring layer for the semiconductor chip 23, and functions as an interposer interposed between the semiconductor chip 23 and the package substrate 31. also works. A cured film of the photosensitive resin composition of the present embodiment can be used to form the insulating layer of the rewiring layer.

According to this embodiment, the semiconductor chip 23 and the rewiring layer (upper wiring layer 25) provided on the surface of the semiconductor chip 23 are provided, and the insulating layer in the rewiring layer is the photosensitive layer of this embodiment. It is possible to realize an electronic device composed of a cured product of a flexible resin composition.

The effect of reinforcing the insulating layer 21 is obtained because the through wiring 221 penetrates the insulating layer 21 . Therefore, even when the mechanical strength of the lower wiring layer 24 and the upper wiring layer 25 is low, the mechanical strength of the entire through electrode substrate 2 can be prevented from being lowered. As a result, the thickness of the lower wiring layer 24 and the upper wiring layer 25 can be further reduced, and the height of the electronic device 1 can be further reduced.

Further, the electronic device 1 shown in FIG. 1 also includes a through wire 222 provided so as to penetrate the insulating layer 21 located on the upper surface of the semiconductor chip 23 in addition to the through wire 221 . Thereby, electrical connection between the upper surface of the semiconductor chip 23 and the upper wiring layer 25 can be achieved.

The insulating layer 21 is provided so as to cover the semiconductor chip 23 . This enhances the effect of protecting the semiconductor chip 23 . As a result, the reliability of the electronic device 1 can be improved. Also, the electronic device 1 can be easily applied to a mounting system such as the package-on-package structure according to the present embodiment.

The diameter W (see FIG. 2) of the through wiring 221 is not particularly limited, but is preferably about 1 to 100 μm, more preferably about 2 to 80 μm. Thereby, the electrical conductivity of the through wiring 221 can be ensured without impairing the mechanical properties of the insulating layer 21 .

The semiconductor package 3 shown in FIG. 1 may be any form of package. For example, QFP (Quad Flat Package), SOP (Small Outline Package), BGA (Ball Grid Array), CSP (Chip Size Package), QFN (Quad Flat Non-leaded Package), SON (Small Outline Package), Forms such as LF-BGA (Lead Flame BGA) can be mentioned.

Although the arrangement of the semiconductor chips 32 is not particularly limited, as an example in FIG. 1, a plurality of semiconductor chips 32 are stacked. As a result, the mounting density is increased. The plurality of semiconductor chips 32 may be arranged side by side in the planar direction, or may be arranged side by side in the planar direction while being stacked in the thickness direction.

The package substrate 31 may be any substrate, but is, for example, a substrate that includes an insulating layer, a wiring layer, a through wiring, etc. (not shown). Among them, the solder bump 35 and the bonding wire 33 can be electrically connected via the through wiring.

The sealing layer 34 is made of, for example, a known sealing resin material. By providing such a sealing layer 34, the semiconductor chip 32 and the bonding wires 33 can be protected from external forces and the external environment.

The semiconductor chip 23 provided in the through electrode substrate 2 and the semiconductor chip 32 provided in the semiconductor package 3 are arranged close to each other. As a result, it is possible to enjoy advantages such as high-speed mutual communication and low loss. From this point of view, for example, one of the semiconductor chip 23 and the semiconductor chip 32 is a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an AP (Application Processor) or other computing element, and the other is a DRAM (Dynamic Random Access). Memory), flash memory, or the like, these elements can be arranged close to each other in the same device. This makes it possible to realize the electronic device 1 that achieves both high functionality and miniaturization.

Next, a method for manufacturing the electronic device 1 shown in FIG. 1 will be described.

FIG. 3 is a process drawing showing a method of manufacturing the electronic device 1 shown in FIG. 4 to 6 are diagrams for explaining a method of manufacturing the electronic device 1 shown in FIG. 1, respectively.

The method of manufacturing the electronic device 1 includes a chip placement step S1 for obtaining an insulating layer 21 so as to embed a semiconductor chip 23 and through

wirings

221 and 222 provided on a substrate 202, and an upper layer on the insulating layer 21 and on the semiconductor chip 23. An upper wiring layer forming step S2 for forming the wiring layer 25, a substrate peeling step S3 for peeling the substrate 202, a lower wiring layer forming step S4 for forming the lower wiring layer 24, a solder bump 26 is formed, and a through electrode substrate is formed. 2 and a stacking step S6 of stacking the semiconductor package 3 on the through electrode substrate 2 .

In the upper wiring layer forming step S2, the photosensitive resin varnish 5 (a varnish-like photosensitive resin composition) is placed on the insulating layer 21 and the semiconductor chip 23 to form a photosensitive resin layer 2510. A film placement step S20, a first exposure step S21 for exposing the photosensitive resin layer 2510, a first development step S22 for developing the photosensitive resin layer 2510, and a curing treatment for the photosensitive resin layer 2510. A first curing step S23, a wiring layer forming step S24 for forming a wiring layer 253, and a second resin for obtaining a photosensitive resin layer 2520 by disposing a photosensitive resin varnish 5 on the photosensitive resin layer 2510 and the wiring layer 253. A film placement step S25, a second exposure step S26 of exposing the photosensitive resin layer 2520, a second developing step S27 of developing the photosensitive resin layer 2520, and a curing treatment of the photosensitive resin layer 2520. A second curing step S28 and a through-wiring forming step S29 of forming the through-wiring 254 in the opening 424 (through-hole) are included.

Each step will be explained below. The following manufacturing method is an example and is not limited to this.

[1] Chip placement step S1
First, as shown in FIG. 4A, a chip including a substrate 202, a semiconductor chip 23 and through

wirings

221 and 222 provided on the substrate 202, and an insulating layer 21 provided so as to bury them An embedded structure 27 is prepared.

The constituent material of the substrate 202 is not particularly limited, but examples include metal materials, glass materials, ceramic materials, semiconductor materials, organic materials, and the like. Also, the substrate 202 may be a semiconductor wafer such as a silicon wafer, a glass wafer, or the like.

The semiconductor chip 23 is adhered onto the substrate 202 . In this manufacturing method, as an example, a plurality of semiconductor chips 23 are arranged side by side on the same substrate 202 while being separated from each other. The plurality of semiconductor chips 23 may be of the same type, or may be of different types. Alternatively, the substrate 202 and the semiconductor chip 23 may be fixed via an adhesive layer (not shown) such as a die attach film.

An interposer (not shown) may be provided between the substrate 202 and the semiconductor chip 23 as required. The interposer functions as a rewiring layer of the semiconductor chip 23, for example. Therefore, the interposer may have pads (not shown) for electrical connection with electrodes of the semiconductor chip 23, which will be described later. As a result, the pad spacing and arrangement pattern of the semiconductor chip 23 can be changed, and the degree of freedom in designing the electronic device 1 can be further enhanced.
For the interposer, for example, an inorganic substrate such as a silicon substrate, a ceramic substrate, or a glass substrate, an organic substrate such as a resin substrate, or the like is used.

The insulating layer 21 may be, for example, a resin film (organic insulating layer) containing a thermosetting resin or a thermoplastic resin such as those listed as components of the photosensitive resin composition, and may be an ordinary sealing layer used in the technical field of semiconductors. It may be a stopping material.

Examples of materials constituting the through-

wirings

221 and 222 include copper or copper alloys, aluminum or aluminum alloys, gold or gold alloys, silver or silver alloys, nickel or nickel alloys, and the like.

A chip-embedded structure 27 manufactured by a method different from the above may be prepared.

[2] Upper wiring layer forming step S2
Next, an upper wiring layer 25 is formed on the insulating layer 21 and the semiconductor chip 23 .

[2-1] First resin film placement step S20
First, as shown in FIG. 4B, the photosensitive resin varnish 5 is applied (arranged) on the insulating layer 21 and the semiconductor chip 23 . As a result, a liquid film of photosensitive resin varnish 5 is obtained as shown in FIG. 4(c). The photosensitive resin varnish 5 is the photosensitive resin composition of this embodiment.

The application of the photosensitive resin varnish 5 is performed using, for example, a spin coater, a bar coater, a spray device, an inkjet device, or the like.

The viscosity of the photosensitive resin varnish 5 is not particularly limited, but is 10 cP to 6000 cP, preferably 20 cP to 5000 cP, more preferably 30 cP to 4000 cP. When the viscosity of the photosensitive resin varnish 5 is within the above range, a thinner photosensitive resin layer 2510 (see FIG. 4D) can be formed. As a result, the upper wiring layer 25 can be made thinner, and the thickness of the electronic device 1 can be easily reduced.
The viscosity of the photosensitive resin varnish 5 is, for example, a value measured using a cone-plate viscometer (TV-25, manufactured by Toki Sangyo Co., Ltd.) at a rotation speed of 100 rpm.

Next, the liquid film of the photosensitive resin varnish 5 is dried. As a result, a photosensitive resin layer 2510 shown in FIG. 4(d) is obtained.

The conditions for drying the photosensitive resin varnish 5 are not particularly limited, but include, for example, heating at a temperature of 80 to 150° C. for 1 to 60 minutes.

In this step, instead of the process of applying the photosensitive resin varnish 5, a process of disposing a photosensitive resin film formed by forming the photosensitive resin varnish 5 into a film may be adopted. The photosensitive resin film is the photosensitive resin composition of the present embodiment and is a resin film having photosensitivity.

A photosensitive resin film is manufactured by applying, for example, a photosensitive resin varnish 5 onto a substrate such as a carrier film using various coating devices, and then drying the resulting coating film.

After forming the photosensitive resin layer 2510 in this manner, the photosensitive resin layer 2510 is subjected to pre-exposure heat treatment as necessary. By performing the pre-exposure heat treatment, the molecules contained in the photosensitive resin layer 2510 are stabilized, and the reaction in the first exposure step S21 described later can be stabilized. On the other hand, by heating under the heating conditions described later, adverse effects on the photoacid generator due to heating can be minimized.

The temperature of the pre-exposure heat treatment is preferably 70 to 130°C, more preferably 75 to 120°C, still more preferably 80 to 110°C. If the temperature of the pre-exposure heat treatment is lower than the lower limit, there is a risk that the pre-exposure heat treatment may fail to achieve the purpose of stabilizing molecules. On the other hand, if the temperature of the pre-exposure heat treatment exceeds the upper limit, the movement of the photo-acid generator becomes too active, and the influence that acid is less likely to be generated even when light is irradiated in the first exposure step S21 described later. becomes wider, and the processing precision of patterning may deteriorate.

The time of the pre-exposure heat treatment is appropriately set according to the temperature of the pre-exposure heat treatment. 6 minutes. If the pre-exposure heat treatment time is less than the lower limit, the heating time will be insufficient, so there is a risk that the pre-exposure heat treatment will fail to achieve the purpose of stabilizing molecules. On the other hand, if the pre-exposure heat treatment time exceeds the above upper limit, the heating time is too long, and even if the pre-exposure heat treatment temperature is within the above range, the action of the photoacid generator is inhibited. There is a risk that it will be lost.

The atmosphere of the heat treatment is not particularly limited. Although an inert gas atmosphere, a reducing gas atmosphere, or the like may be used, the atmosphere is selected in consideration of work efficiency and the like.

The atmospheric pressure is not particularly limited. It may be under reduced pressure or under increased pressure, but considering work efficiency, etc., normal pressure is used. The normal pressure means a pressure of about 30 to 150 kPa, preferably atmospheric pressure.

[2-2] First exposure step S21
Next, the photosensitive resin layer 2510 is subjected to exposure processing.

First, as shown in FIG. 4(d), a mask 412 is placed on a predetermined region on the photosensitive resin layer 2510. Then, as shown in FIG. Then, light (activating radiation) is irradiated through a mask 412 . As a result, the photosensitive resin layer 2510 is exposed according to the pattern of the mask 412 .

FIG. 4(d) illustrates a case where the photosensitive resin layer 2510 has so-called negative photosensitivity. In this example, the areas of the photosensitive resin layer 2510 corresponding to the light shielding portions of the mask 412 dissolve in the developer.

On the other hand, in the region corresponding to the transparent portion of the mask 412, active chemical species are generated from the photosensitive agent (C). The active species act as catalysts for the curing reaction.

The amount of exposure in the exposure process is not particularly limited. 100 to 2000 mJ/cm ² is preferred, and 200 to 1000 mJ/cm ² is more preferred. Thereby, underexposure and overexposure in the photosensitive resin layer 2510 can be suppressed. As a result, it is possible to finally achieve high patterning precision.
After that, if necessary, the photosensitive resin layer 2510 is subjected to post-exposure heat treatment.

The temperature of the post-exposure heat treatment is not particularly limited. It is preferably 50 to 150°C, more preferably 50 to 130°C, even more preferably 55 to 120°C, and particularly preferably 60 to 110°C. By performing post-exposure heat treatment at such a temperature, the catalytic action of the generated acid is sufficiently enhanced, and the thermosetting resin can be sufficiently reacted in a shorter time. By setting the temperature within the above range, it is possible to suppress deterioration in the processing accuracy of patterning due to promotion of acid diffusion.
By setting the temperature of the post-exposure heat treatment to the above lower limit or more, the reaction rate of the thermosetting resin can be increased, and the productivity can be improved. On the other hand, by setting the temperature of the post-exposure heat treatment to be equal to or lower than the above upper limit, it is possible to suppress deterioration in processing accuracy of patterning due to promotion of acid diffusion.

The time for the post-exposure heat treatment is appropriately set according to the temperature of the post-exposure heat treatment. At the above temperature, it is preferably 1 to 30 minutes, more preferably 2 to 20 minutes, still more preferably 3 to 15 minutes. By performing the post-exposure heat treatment for such a time, the thermosetting resin can be sufficiently reacted, and diffusion of the acid can be suppressed, thereby suppressing deterioration of the processing accuracy of patterning.

The atmosphere of the post-exposure heat treatment is not particularly limited. Although an inert gas atmosphere, a reducing gas atmosphere, or the like may be used, the atmosphere is selected in consideration of work efficiency and the like.

The atmospheric pressure of the post-exposure heat treatment is not particularly limited. It may be under reduced pressure or under increased pressure, but considering work efficiency, etc., normal pressure is used. As a result, pre-exposure heat treatment can be performed relatively easily. The normal pressure means a pressure of about 30 to 150 kPa, preferably atmospheric pressure.

[2-3] First development step S22
Next, the photosensitive resin layer 2510 is developed. As a result, openings 423 penetrating through the photosensitive resin layer 2510 are formed in regions corresponding to the light shielding portions of the mask 412 (see FIG. 5E).

Examples of the developer include organic developer and water-soluble developer. In this embodiment, the developer preferably contains an organic solvent. More specifically, the developer is preferably a developer containing an organic solvent as a main component (a developer in which 95% by mass or more of the component is an organic solvent). By developing with a developer containing an organic solvent, swelling of the pattern due to the developer can be suppressed more than in the case of developing with an alkaline developer (aqueous). That is, it is easy to obtain a finer pattern.

Specific examples of organic solvents that can be used in the developer include ketone solvents such as cyclopentanone, ester solvents such as propylene glycol monomethyl ether acetate (PGMEA) and butyl acetate, ether solvents such as propylene glycol monomethyl ether, etc.
As the developer, an organic solvent developer containing only an organic solvent and containing only unavoidable impurities may be used. Impurities that are unavoidably contained include metal elements and moisture, but from the viewpoint of preventing contamination of electronic devices, it is better that the impurities that are unavoidably contained are as small as possible.

The method of bringing the developer into contact with the photosensitive resin layer 2510 is not particularly limited. A generally known dipping method, paddle method, spray method, or the like can be appropriately applied.

The time for the development process is usually in the range of about 5 to 300 seconds, preferably about 10 to 120 seconds, and is appropriately adjusted based on the film thickness of the resin film, the shape of the pattern to be formed, and the like.

[2-4] First curing step S23
After the development process, the photosensitive resin layer 2510 is subjected to a curing process (post-development heat treatment). Conditions for the curing treatment are not particularly limited, but the heating temperature is about 160 to 250° C. and the heating time is about 30 to 240 minutes. As a result, the photosensitive resin layer 2510 can be cured and the organic insulating layer 251 can be obtained while suppressing the thermal effect on the semiconductor chip 23 .

[2-5] Wiring layer forming step S24
Next, a wiring layer 253 is formed on the organic insulating layer 251 (see FIG. 5F). The wiring layer 253 is formed by, for example, obtaining a metal layer using a vapor deposition method such as a sputtering method or a vacuum vapor deposition method, followed by patterning using a photolithography method and an etching method.
Prior to forming the wiring layer 253, surface modification treatment such as plasma treatment may be performed.

[2-6] Second resin film placement step S25
Next, as shown in FIG. 5G, a photosensitive resin layer 2520 is obtained in the same manner as in the first resin film placement step S20. A photosensitive resin layer 2520 is arranged to cover the wiring layer 253 .
After that, pre-exposure heat treatment is applied to the photosensitive resin layer 2520 as necessary. The processing conditions are, for example, the conditions described in the first resin film placement step S20.

[2-7] Second exposure step S26
Next, the photosensitive resin layer 2520 is exposed. The processing conditions are, for example, the conditions described in the first exposure step S21.
After that, if necessary, the photosensitive resin layer 2520 is subjected to post-exposure heat treatment. The processing conditions are, for example, the conditions described in the first exposure step S21.

[2-8] Second development step S27
Next, the photosensitive resin layer 2520 is developed. Processing conditions are, for example, the conditions described in the first development step S22. As a result, openings 424 penetrating through the

photosensitive resin layers

2510 and 2520 are formed (see FIG. 5(h)).

[2-9] Second curing step S28
After the development process, the photosensitive resin layer 2520 is subjected to a curing process (post-development heat treatment). The curing conditions are, for example, the conditions described in the first curing step S23. Thereby, the photosensitive resin layer 2520 is cured to obtain the organic insulating layer 252 (see FIG. 6(i)).

Although the upper wiring layer 25 has two layers of the organic insulating layer 251 and the organic insulating layer 252 in this embodiment, it may have three or more layers. In this case, after the second curing step S28, a series of steps from the wiring layer forming step S24 to the second curing step S28 may be added repeatedly.

[2-10] Through-wiring forming step S29
Next, the through wiring 254 shown in FIG. 6I is formed in the opening 424 .

A known method is used to form the through wiring 254, and for example, the following method is used.

First, a seed layer (not shown) is formed on the organic insulating layer 252 . A seed layer is formed on the top surface of the organic insulating layer 252 as well as the inner surfaces (sides and bottom) of the opening 424 .
For example, a copper seed layer is used as the seed layer. Also, the seed layer is formed by, for example, a sputtering method.
The seed layer may be made of the same kind of metal as the through-wiring 254 to be formed, or may be made of a different kind of metal.

Next, a resist layer (not shown) is formed on a region of the seed layer (not shown) other than the opening 424 . Using this resist layer as a mask, the opening 424 is filled with metal. Electroplating, for example, is used for this filling. Examples of metals to be filled include copper or copper alloys, aluminum or aluminum alloys, gold or gold alloys, silver or silver alloys, nickel or nickel alloys, and the like. In this manner, the conductive material is embedded in the opening 424 to form the through wiring 254 .

Next, the resist layer (not shown) is removed. Furthermore, the seed layer (not shown) on the organic insulating layer 252 is removed. For this, for example, a flash etching method can be used.
The position where the through wire 254 is formed is not limited to the illustrated position.

[3] Substrate peeling step S3
Next, as shown in FIG. 6(j), the substrate 202 is peeled off. As a result, the lower surface of the insulating layer 21 is exposed.

[4] Lower wiring layer forming step S4
Next, as shown in FIG. 6(k), a lower wiring layer 24 is formed on the lower surface side of the insulating layer 21. Next, as shown in FIG. The lower wiring layer 24 may be formed by any method, for example, it may be formed in the same manner as the upper wiring layer forming step S2 described above.
The lower wiring layer 24 formed in this way is electrically connected to the upper wiring layer 25 via the through wiring 221 .

[5] Solder bump formation step S5
Next, as shown in FIG. 6L, solder bumps 26 are formed on the lower wiring layer 24 . Moreover, a protective film such as a solder resist layer may be formed on the upper wiring layer 25 and the lower wiring layer 24 as necessary.
The through electrode substrate 2 is obtained as described above.

The through electrode substrate 2 shown in FIG. 6(l) can be divided into a plurality of regions. Therefore, a plurality of through electrode substrates 2 can be efficiently manufactured by singulating the through electrode substrates 2 along the dashed line shown in FIG. 6(l), for example. In addition, for example, a diamond cutter or the like can be used for singulation.

[6] Lamination step S6
Next, the semiconductor package 3 is arranged on the through electrode substrate 2 that has been divided into pieces. Thereby, the electronic device 1 shown in FIG. 1 is obtained.

Such a method for manufacturing the electronic device 1 can be applied to wafer-level processes and panel-level processes using large-area substrates. Thereby, the manufacturing efficiency of the electronic device 1 can be improved and the cost can be reduced.

<Optical device>
The optical device of this embodiment is
a light emitting element;
wiring electrically connected to the light emitting element;
and an insulating film covering the wiring,
The insulating film is a cured film of the photosensitive resin composition.

Optical devices include display devices such as liquid crystal displays, organic EL displays, touch panels, electronic paper, color filters, mini LED displays, and micro LED displays; light emitting devices such as LEDs, mini LEDs, micro LEDs, and laser diodes; solar cells, CMOS and the like, and can be used for rewiring layers, interlayer insulating films, sealing materials (top coats), and the like. The photosensitive resin composition of this embodiment can be suitably used particularly for micro LEDs.

The method for manufacturing the optical device of the present embodiment, the structure of the optical device including the cured product of the photosensitive resin composition of the present embodiment, and the like will be described below in more detail with reference to the drawings.

(Film Forming Step: FIG. 7A) In the film forming step, the photosensitive resin composition of the present embodiment is used to form a photosensitive resin film 73 on the surface of the substrate 71 having the step 710 .
The substrate 71 is not particularly limited. Examples of the substrate 71 include silicon wafers, ceramic substrates, aluminum substrates, SiC wafers, and GaN wafers.
The step 710 is, for example, a Cu rewiring. Of course, the step 710 may be a step other than Cu rewiring. The height of the step 710 is, for example, 1-10 μm, preferably 1-5 μm.
The thickness of the photosensitive resin film 73 (thickness of the portion without the step 710) is, for example, 1 to 15 μm, preferably 1 to 10 μm. This thickness should be greater than the height of the step 710 .

As a method of forming the photosensitive resin film 73, a method of providing a liquid photosensitive resin composition on the substrate by a spin coating method, a spray coating method, a dipping method, a printing method, a roll coating method, an inkjet method, or the like can be used. can be mentioned. The method of forming the resin film is typically spin coating.
The thickness of the photosensitive resin film 73 can be adjusted by changing the film formation conditions or by adjusting the viscosity of the photosensitive resin composition.

It is preferable to dry the photosensitive resin film 73 by heating after the film formation process and before the exposure process. This heat drying is sometimes called "pre-baking".
The temperature for drying by heating is usually 50 to 180°C, preferably 60 to 150°C. The heat drying time is usually 30 to 600 seconds, preferably about 30 to 300 seconds. This heat drying can sufficiently remove the solvent in the photosensitive resin composition. Heating is typically done with a hot plate, an oven, or the like.

(Exposure step: FIG. 7B)
In the exposure step, the photosensitive resin film 73 is exposed through a photomask 720 . Actinic rays for exposure include, for example, X-rays, electron beams, ultraviolet rays, and visible rays. In terms of wavelength, actinic rays of 200 to 500 nm are preferred. The light source is preferably g-line, h-line or i-line of a mercury lamp in terms of pattern resolution and ease of handling of the apparatus. Also, two or more rays may be mixed and used.
A contact aligner, mirror projection or stepper is preferred as the exposure device.
The exposure dose in the exposure step is usually 40 to 1500 mJ/cm ² , preferably 80 to 1000 mJ/cm ² , depending on the sensitivity of the photosensitive resin composition, the thickness of the resin film, the shape of the pattern to be obtained, etc. adjusted accordingly.

It is preferable to heat the resin film (post-exposure heating) between the exposure process and the development process. As a result, the reaction of the substance (photosensitive agent, etc.) that has been cleaved or decomposed by the exposure proceeds, and improvement of the pattern shape can be expected. The temperature and time of post-exposure heating are, for example, about 50 to 200° C. and about 10 to 600 seconds.

(Development process: FIG. 7C)
In the developing step, the photosensitive resin film exposed in the exposing step is developed using a developer. As a result, a part of the photosensitive resin film 73 is removed to obtain a resin film 73A provided with the openings 75. Next, as shown in FIG. The photosensitive resin composition of this embodiment is usually negative. Therefore, an opening 75 is provided in a portion corresponding to the light shielding portion of the photomask 720 .
The development process can be carried out, for example, by a dipping method, a puddle method, a rotary spray method, or the like.

In this embodiment, the developer preferably contains an organic solvent. More specifically, the developer is preferably a developer containing an organic solvent as a main component (a developer in which 95% by mass or more of the component is an organic solvent). By developing with a developer containing an organic solvent, swelling of the pattern due to the developer can be suppressed more than in the case of developing with an alkaline developer (aqueous). That is, it is easy to obtain a finer pattern.

Specific examples of organic solvents that can be used in the developer include ketone solvents such as cyclopentanone, ester solvents such as propylene glycol monomethyl ether acetate (PGMEA) and butyl acetate, ether solvents such as propylene glycol monomethyl ether, etc.
As the developer, an organic solvent developer containing only an organic solvent and containing only unavoidable impurities may be used. Incidentally, impurities that are unavoidably contained include metallic elements, but from the viewpoint of preventing contamination of electronic devices, it is better that the impurities that are unavoidably contained are as small as possible.

For example, there may be a curing process for curing the resin film 73A between the developing process and the subsequent process. Curing can be performed, for example, by heat treatment at 150 to 250° C. for 30 to 240 minutes. By forming the resin film 73A using the photosensitive resin composition of the present embodiment, the surface (upper surface) of the resin film 73A has good flatness even after such a curing process.

(Additional rewiring process: FIG. 7D)
A Cu rewiring 711 different from the step 710 (for example, a Cu rewiring) can be provided in the portion of the opening 75 provided in the development process. At this time, since the flatness of the upper surface of the resin film 73A is high, the fine Cu rewiring 711 can be provided with high precision.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than those described above can be adopted. Moreover, the present invention is not limited to the above-described embodiments, and includes modifications, improvements, etc. within the scope of achieving the object of the present invention.

Embodiments of the present invention will be described in detail based on examples and comparative examples. It should be noted that the invention is not limited to the examples only.
In the following, "TEMPO" is an abbreviation for "2,2,6,6-tetramethylpiperidine-1-oxyl". Other abbreviations will be explained appropriately in the text.

<Synthesis of polyimide resin>
(Synthesis of polyimide resin (A-1))
Into a 5 L separable flask equipped with a stirrer and condenser, 304.2 g (0.95 mol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB), 4,4′-(hexafluoroisopropylidene ) 355.39 g (0.80 mol) of diphthalic anhydride (6FDA), 62.04 g (0.20 mol) of 4,4'-oxydiphthalic dianhydride and 1684 g of GBL were added, and the mixture was stirred at room temperature for 16 minutes under a nitrogen atmosphere. Polymerization reaction was carried out by reacting for time. Subsequently, the temperature of the reaction liquid was raised to 180° C. in an oil bath and the reaction was carried out for 3 hours, and then cooled to room temperature to prepare a polyimide resin solution.
Subsequently, the reaction solution was added dropwise to a mixed solution of isopropanol/water=4/7 with stirring to precipitate a resin solid. After rough filtration of the obtained solid, it was further washed with isopropanol/water=4/7 to obtain a white polyimide solid. The resulting white solid was vacuum dried at 200° C. to obtain a polyimide resin (A-1) having an acid anhydride group at the terminal.
The weight average molecular weight (Mw) of the polyimide resin (A-1) measured by GPC was 49,000. Further, the imidization rate of the polyimide resin (A-1) was 98% by NMR measurement.

(Synthesis of polyimide resin (A-2))
268.3 g (0.95 mol) of 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane (MED-J), 4- [4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5- 494.87 g (0.8 mol) of carboxylate (TMPBP-TME), 62.04 g (0.20 mol) of 4,4'-oxydiphthalic dianhydride and 1684 g of GBL were added, and the mixture was stirred at room temperature for 16 hours under a nitrogen atmosphere. A polymerization reaction was carried out by reacting. Subsequently, the temperature of the reaction liquid was raised to 180° C. in an oil bath and the reaction was carried out for 3 hours, and then cooled to room temperature to prepare a polyimide resin solution.
Subsequently, the reaction solution was added dropwise to a mixed solution of isopropanol/water=4/7 with stirring to precipitate a resin solid. After rough filtration of the obtained solid, it was further washed with isopropanol/water=4/7 to obtain a white polyimide solid. The resulting white solid was vacuum dried at 200° C. to obtain a polyimide resin (A-2) having an acid anhydride group at its end.
The weight average molecular weight (Mw) of the polyimide resin (A-2) measured by GPC was 49,000. Further, the imidization rate of the polyimide resin (A-2) was 98% by NMR measurement.

(Synthesis of polyimide resin (A-3))
304.22 g (0.95 mol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB), 4-[4-(1,3- Dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5-carboxylate (TMPBP-TME) 494 87 g (0.8 mol), 62.04 g (0.20 mol) of 4,4'-oxydiphthalic dianhydride and 1684 g of GBL were added and reacted at room temperature for 16 hours under a nitrogen atmosphere to carry out a polymerization reaction. Subsequently, the temperature of the reaction liquid was raised to 180° C. in an oil bath and the reaction was carried out for 3 hours, and then cooled to room temperature to prepare a polyimide resin solution.
Subsequently, the reaction solution was added dropwise to a mixed solution of isopropanol/water=4/7 with stirring to precipitate a resin solid. After rough filtration of the obtained solid, it was further washed with isopropanol/water=4/7 to obtain a white polyimide solid. The resulting white solid was vacuum dried at 200° C. to obtain a polyimide resin (A-3) having an acid anhydride group at its end.
The weight average molecular weight (Mw) of the polyimide resin (A-3) measured by GPC was 49,000. Further, the imidization rate of the polyimide resin (A-3) was 98% by NMR measurement.

(Synthesis of polyimide resin (A-4))
In a 5 L separable flask equipped with a stirrer and condenser, 304.22 g (0.95 mol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB), 4,4′-(hexafluoroisopropylidene ) 355.89 g (0.8 mol) of diphthalic anhydride (6FDA), 62.04 g (0.20 mol) of 4,4′-oxydiphthalic dianhydride and 1684 g of GBL were added, and the mixture was stirred at room temperature for 16 minutes under a nitrogen atmosphere. Polymerization reaction was carried out by reacting for time. Subsequently, the temperature of the reaction liquid was raised to 180° C. in an oil bath and the reaction was carried out for 3 hours, and then cooled to room temperature to prepare a polyimide resin solution.
Subsequently, the reaction solution was added dropwise to a mixed solution of isopropanol/water=4/7 with stirring to precipitate a resin solid. After rough filtration of the obtained solid, it was further washed with isopropanol/water=4/7 to obtain a white polyimide solid. The resulting white solid was vacuum dried at 200° C. to obtain a polyimide resin (A-4) having an acid anhydride group at its end.
The weight average molecular weight (Mw) of the polyimide resin (A-4) measured by GPC was 49,000. Further, the imidization rate of the polyimide resin (A-4) was 98% by NMR measurement.

<Preparation of photosensitive resin composition>
Each raw material blended according to Table 1 below was stirred at room temperature until the raw material was completely dissolved to obtain a solution. The solution was then filtered through a nylon filter with a pore size of 0.2 μm. Thus, a varnish-like photosensitive resin composition was obtained.

The details of the raw materials for each component in Table 1 are as follows.

<(A) Polyimide resin>
(A-1) Polyimide resin synthesized above (A-1)
(A-2) Polyimide resin synthesized above (A-2)
(A-3) Polyimide resin synthesized above (A-3)
(A-4) Polyimide resin synthesized above (A-4)

<(B) Polyfunctional (meth)acrylate compound>
(B-1) Viscoat #195 (manufactured by Osaka Organic Industry Co., Ltd., 1,4-butanediol diacrylate)
(B-2) Viscoat #802 (manufactured by Osaka Organic Industry Co., Ltd., a mixture of compounds having 5 to 10 acryloyl groups)
(B-3) A-9550 (manufactured by Shin-Nakamura Chemical Co., Ltd., a mixture of compounds having 5 to 6 acryloyl groups)
(B-4) Viscoat #300 (manufactured by Osaka Organic Industry Co., Ltd., a mixture of compounds having 3 to 4 acryloyl groups)

The structures of (B-1) to (B-4) above are shown below.

<(C) Photosensitizer>
(C-1) Irugacure OXE01 (manufactured by BASF, oxime ester type photoradical generator)

<(E) Thermal radical generator>
(E-1) Perkadox BC (manufactured by Kayaku Nourion Co., Ltd., organic peroxide, dicumyl peroxide)

<(F) Crosslinking agent>
(F-1) 4HBAGE (manufactured by Mitsubishi Chemical Corporation, 4-hydroxybutyl acrylate glycidyl ether, compound of chemical formula (2))
(F-2) Cychromer M100 (manufactured by Daicel Corporation, 3,4-epoxycyclohexylmethyl methacrylate, compound of chemical formula (3))

<(G) Silane coupling agent>
(G-1) X-12-967C (manufactured by Shin-Etsu Chemical Co., Ltd.)
(G-2) KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.)

<(H) Curing catalyst>
(H-1) Tetraphenylphosphonium/4,4'-sulfonyldiphenolate A method for synthesizing the curing catalyst (H-1) is as follows.
A separable flask equipped with a stirrer was charged with 37.5 g (0.15 mol) of 4,4′-bisphenol S and 100 mL of methanol, and dissolved with stirring at room temperature. A solution of 0 g (0.1 mol) was added. Then, a solution in which 41.9 g (0.1 mol) of tetraphenylphosphonium bromide was previously dissolved in 150 mL of methanol was added. After continuing stirring for a while and adding 300 mL of methanol, the solution in the flask was added dropwise to a large amount of water while stirring to obtain a white precipitate. The precipitate was filtered and dried. As a result, a white crystalline curing catalyst (H-1) was obtained.

<(I) Surfactant>
(I-1) FC4432 (manufactured by 3M, fluorine-based)

<(J) (solvent)>
(J-1) γ-butyrolactone (GBL)
(J-2) Ethyl lactate (EL)

<(D) polymerization inhibitor>
(D-1) Irganox 1035 (manufactured by BASF, hindered phenolic compound)
(D-2) Irganox 1010 (manufactured by BASF, hindered phenolic compound)
(D-3) 4-benzoyloxy TEMPO (manufactured by Seiko Chemical Co., Ltd., N-oxyl compound)
(D-4) 2,6-di-tert-butyl-p-cresol (manufactured by Tokyo Chemical Industry Co., Ltd., hindered phenol compound)
(D-5) N,N-diphenylnitrosamide (manufactured by Tokyo Chemical Industry Co., Ltd., N-oxyl compound)
(D-6) Capferon (manufactured by Tokyo Chemical Industry Co., Ltd., N-oxyl compound)
(D-7) TEMPO (Tokyo Chemical Industry Co., Ltd., N-oxyl compound)
(D-8) 4-hydroxy TEMPO (manufactured by Seiko Chemical Co., Ltd., N-oxyl compound)
(D-9) BisTEMPO sebacate (manufactured by Seiko Chemical Co., Ltd., N-oxyl compound)
(D-10) Irganox 1726 (manufactured by BASF, hindered phenolic compound)
(D-11) Irganox 1520L (manufactured by BASF, hindered phenolic compound)

The structures of (D-1) to (D-11) above are shown below.

<Evaluation of Focus Margin>
The photosensitive resin composition of each example and comparative example was applied onto a 12-inch plated copper (Ra=0.08 μm) wafer using a spin coater so that the film thickness after drying was 5 μm. After that, it was dried on a hot plate at 120° C. for 3 minutes to obtain a photosensitive resin film.
This photosensitive resin film is passed through a photomask (on which a pattern of 3 μmφ circular via holes is drawn), and an i-line stepper (CANON, FPA-5500iX, NA=0.28) is used to adjust the exposure dose. The i-line was irradiated while changing the amount of change from 190 mJ to 550 mJ by 30 mJ/min and the focus from −9 μm to +3 μm by the amount of change of 1 μm.
After that, it was developed using cyclopentanone as a developer at 2500 rpm for 30 seconds, rinsed with PGMEA at 2500 rpm for 10 seconds, and dried by spinning for 20 seconds to obtain a film after development (negative pattern). rice field. After that, it was dried on a hot plate at 170° C. for 10 minutes, and then heat-treated at 200° C. for 120 minutes in a nitrogen atmosphere. As described above, a cured product of the photosensitive resin composition was obtained.
Within the exposure dose range described above, the difference between the maximum value and the minimum value of focus was calculated as a focus margin for a via hole of 3 μmΦ without generating a foot or bridge. Described. In each example and comparative example, when the focus margin can be calculated for a plurality of exposure doses, the value of the largest focus margin is described.

<Evaluation of tensile elongation>
(Preparation of test piece for measuring tensile elongation)
The photosensitive resin composition was spin-coated on an 8-inch silicon wafer so that the film thickness after drying was 10 μm, followed by heating at 120° C. for 3 minutes to obtain a photosensitive resin film.
The resulting photosensitive resin film was exposed to light at 300 mJ/cm ² with a high-pressure mercury lamp. Thereafter, the exposed resin film was immersed in cyclopentanone together with the silicon wafer for 30 seconds. After that, heat treatment was performed at 200° C. for 120 minutes in a nitrogen atmosphere. As described above, a cured product of the photosensitive resin composition was obtained.
The obtained cured product was cut together with the silicon wafer with a dicing saw so as to have a width of 5 mm, and then separated from the substrate by being immersed in a 2 mass % hydrofluoric acid aqueous solution. The peeled film was dried at 60° C. for 10 hours to obtain a test piece (30 mm×5 mm×10 μm thick).

(Measurement of tensile elongation)
The resulting test piece was subjected to a tensile test using a tensile tester (Tensilon RTC-1210A, manufactured by Orientec Co., Ltd.) in an atmosphere of 23° C. in accordance with JIS K 7161, and the tensile elongation of the test piece was measured. It was measured. The drawing speed in the tensile test was 5 mm/min. The unit of tensile elongation is %.

Table 1 shows the composition of raw materials for each composition and the above evaluation results.

As shown in Table 1, the photosensitive resin compositions of Examples 1 to 32 had a large focus margin while having good elongation.

This application claims priority based on Japanese Patent Application No. 2021-161640 filed on September 30, 2021, and the entire disclosure thereof is incorporated herein.

1 Electronic device 1A Electronic device 1B Electronic device 2 Penetrating electrode substrate 3 Semiconductor package 5 Photosensitive resin varnish 21 Insulating layer 23 Semiconductor chip 24 Lower wiring layer 24A Lower wiring layer 24B Lower wiring layer 25 Upper wiring layer 26 Solder bump 27 Chip embedding Structure 31 Package substrate 32 Semiconductor chip 33 Bonding wire 34 Sealing layer 35 Solder bump 202 Substrate 221 Through wiring 222 Through wiring 231 Land 240 Organic insulation layer 241 Organic insulation layer 242 Organic insulation layer 243 Wiring layer 245 Bump adhesion layer 251 Organic insulation Layer 252 Organic insulating layer 253 Wiring layer 254 Through wiring 412 Mask 423 Opening 424 Opening 2510 Photosensitive resin layer 2520 Photosensitive resin layer 71 Substrate 73 Photosensitive resin film 73A Resin film 75 Opening 710 Step 711 Cu rewiring 720 Photomask S1 chip placement step S2 upper wiring layer formation step S20 first resin film placement step S21 first exposure step S22 first development step S23 first curing step S24 wiring layer formation step S25 second resin film placement step S26 second exposure step S27 Second developing step S28 Second curing step S29 Penetration wire forming step S3 Substrate peeling step S4 Lower wiring layer forming step S5 Solder bump forming step S6 Stacking step W Diameter

Claims

a polyimide resin (A);
a polyfunctional (meth)acrylate compound (B);
a photosensitizer (C);
a polymerization inhibitor (D);
A photosensitive resin composition comprising
The polyimide resin (A) contains a structure represented by the following general formula (a),

In general formula (a),
X is a divalent organic group,
Y is a tetravalent organic group,
A photosensitive resin composition.
The photosensitive resin composition according to claim 1,
IM is the number of moles of imide groups contained in the polyimide resin (A),
When the number of moles of amide groups contained in the polyimide resin (A) is AM,
A photosensitive resin composition having an imidization rate of 90% or more, as expressed by {IM/(IM+AM)}×100(%).
The photosensitive resin composition according to claim 1 or 2,
The polyimide resin (A) is a photosensitive resin composition containing a polyimide resin containing a fluorine atom.
The photosensitive resin composition according to any one of claims 1 to 3,
A photosensitive resin composition, wherein the polyfunctional (meth)acrylate compound (B) contains a tri- to tetra-functional (meth)acrylate compound (B1).
The photosensitive resin composition according to any one of claims 1 to 4,
A photosensitive resin composition, wherein the polyfunctional (meth)acrylate compound (B) contains a pentafunctional or higher (meth)acrylate compound (B2).
The photosensitive resin composition according to any one of claims 1 to 5,
A photosensitive resin composition in which the content of the polyfunctional (meth)acrylate compound (B) is 25 parts by mass or more and 100 parts by mass or less relative to 100 parts by mass of the polyimide resin (A).
The photosensitive resin composition according to any one of claims 1 to 6,
The photosensitive resin composition, wherein the photosensitive agent (C) contains a photoradical generator.
The photosensitive resin composition according to claim 7,
The photosensitive resin composition, wherein the photo-radical generator comprises an oxime ester-based photo-radical generator.
The photosensitive resin composition according to any one of claims 1 to 8,
A photosensitive resin composition in which the content of the photosensitive agent (C) is 5 parts by mass or more and 30 parts by mass or less relative to 100 parts by mass of the polyimide resin (A).
The photosensitive resin composition according to any one of claims 1 to 9,
A photosensitive resin composition, wherein the polymerization inhibitor (D) contains one or more compounds selected from hindered phenol compounds and N-oxyl compounds.
The photosensitive resin composition according to any one of claims 1 to 10,
The photosensitive resin composition, wherein the content of the polymerization inhibitor (D) with respect to 100 parts by mass of the polyimide resin (A) is 0.1 parts by mass or more and 5 parts by mass or less.
The photosensitive resin composition according to any one of claims 1 to 11,
The photosensitive resin composition, wherein the content of the polymerization inhibitor (D) with respect to 100 parts by mass of the photosensitive agent (C) is 1 part by mass or more and 30 parts by mass or less.
The photosensitive resin composition according to any one of claims 1 to 12,
A photosensitive resin composition further comprising a thermal radical generator (E).
The photosensitive resin composition according to any one of claims 1 to 13,
A photosensitive resin composition further comprising a cross-linking agent (F).
The photosensitive resin composition according to claim 14,
The photosensitive resin composition, wherein the cross-linking agent (F) comprises a compound having one epoxy-containing group at one end of the molecule and one (meth)acryloyl group at the other end of the molecule.
The photosensitive resin composition according to any one of claims 1 to 15,
A photosensitive resin composition further comprising a silane coupling agent (G).
The photosensitive resin composition according to any one of claims 1 to 16,
A photosensitive resin composition used for forming an insulating layer in an electronic device.
The photosensitive resin composition according to any one of claims 1 to 16,
A photosensitive resin composition used for forming an insulating layer in an optical device.
A film forming step of forming a photosensitive resin film on a substrate using the photosensitive resin composition according to any one of claims 1 to 17;
an exposure step of exposing the photosensitive resin film;
a developing step of developing the exposed photosensitive resin film;
A method of manufacturing an electronic device, comprising:
A method for manufacturing an electronic device according to claim 19,
A method of manufacturing an electronic device, comprising a thermosetting step of heating and curing the exposed photosensitive resin film after the developing step.
An electronic device comprising a cured film of the photosensitive resin composition according to any one of claims 1 to 17.
a light emitting element;
wiring electrically connected to the light emitting element;
and an insulating film covering the wiring,
An optical device, wherein the insulating film is a cured film of the photosensitive resin composition according to any one of claims 1 to 16 and 18.
The optical device according to claim 22, wherein said light emitting element is a micro LED.