JP2024012299A - Photosensitive resin composition, method for producing electronic device, electronic device, and light device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition that exhibits a large focus margin while offering moderate stretchability.

SOLUTION: 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 represented by general formula (a) (in the general formula (a), X represents a divalent organic group, and Y represents a tetravalent organic group); an electronic device which includes an insulating layer that is formed of this photosensitive resin composition; and a light device which includes an insulating layer that is formed of this photosensitive resin composition.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a photosensitive resin composition, a method for manufacturing an electronic device, 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 studied so far.

By way of example, U.S. Pat. A photosensitive composition is described that is capable of forming a film having a dissolution rate greater than about 0.15 μm/sec when using cyclopentanone as a developer, the photoinitiator; and at least one solvent. ing.

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

International Publication No. 2016/172092 International Publication No. 2007/047384 Japanese Patent Application Publication No. 2018-070829

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

The present invention has been made in view of these circumstances. One of the objects of the present invention is to provide a photosensitive resin composition with a large focus margin while having appropriate elongation properties.

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

一般式（ａ）中、
Ｘは２価の有機基であり、
Ｙは４価の有機基である、
感光性樹脂組成物が提供される。 According to the invention,
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.

Further, according to the present invention,
a film forming step of forming a photosensitive resin film on the 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;
Provided is a method of manufacturing an electronic device, including:

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

Further, according to the present invention,
A light emitting element,
Wiring electrically connected to the light emitting element;
an insulating film covering the wiring,
An optical device is provided in which the insulating film is a cured film of the photosensitive resin composition described above.

According to the present invention, a photosensitive resin composition having appropriate elongation properties and a large focus margin is provided.

1 is a longitudinal cross-sectional view showing an example of the configuration of an electronic device according to an embodiment. FIG. 2 is a partially enlarged view of the area surrounded by the chain line in FIG. 1. FIG. 2 is a process diagram showing a method for manufacturing the electronic device shown in FIG. 1. FIG. 2 is a diagram for explaining a method of manufacturing the electronic device shown in FIG. 1. FIG. 2 is a diagram for explaining a method of manufacturing the electronic device shown in FIG. 1. FIG. 2 is a diagram for explaining a method of manufacturing the electronic device shown in FIG. 1. FIG. FIG. 3 is a diagram for explaining a method of manufacturing an optical device according to the present embodiment.

Embodiments of the present invention will be described in detail below with reference to the drawings.
In all the drawings, similar components are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
To avoid complication, (i) if there are multiple identical components in the same drawing, only one of them will be given a reference numeral and not all of them, or (ii) especially 2 and subsequent parts, components similar to those in FIG. 1 may not be labeled again.
All drawings are for illustrative purposes only. The shapes and dimensional ratios of each member in the drawings do not necessarily correspond to the actual product.

In this specification, the term "substantially" includes a range that takes into account manufacturing tolerances, assembly variations, etc., unless explicitly stated otherwise.
In the present specification, the notation "X to Y" in the description of numerical ranges refers to not less than X and not more than Y, unless otherwise specified. For example, "1 to 5% by mass" means "1 to 5% by mass".

In the description of a group (atomic group) in this specification, a description that does not indicate whether it is substituted or unsubstituted includes both those without a substituent and those with a substituent. For example, the term "alkyl group" includes not only an alkyl group without a substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
In this specification, the expression "(meth)acrylic" represents a concept that includes both acrylic and methacrylic. The same applies to similar expressions 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" refers to an atomic group obtained by removing one hydrogen atom from an arbitrary organic compound.
In this specification, the term "electronic device" refers to an element to which electronic engineering technology is applied, such as a semiconductor chip, semiconductor element, printed wiring board, electric circuit display device, information communication terminal, light emitting diode, physical battery, chemical battery, etc. , devices, final products, etc.

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

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

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

On the other hand, the photosensitive resin composition of this embodiment already contains the polyimide resin (A) before use (before forming a cured film). Furthermore, in this embodiment, a polymerization reaction of the polyfunctional (meth)acrylate compound (B) was employed as a curing mechanism (this polymerization reaction does not involve dehydration in principle). Due to 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 with steps.

Moreover, by using the photosensitive resin composition of this embodiment, it is easy to form a cured film with good heat resistance and good mechanical properties (for example, tensile elongation rate).
Cured films in electronic devices are often required to have high heat resistance and good mechanical properties. However, in the past, when resins were designed to be rigid in an attempt to increase heat resistance, the flexibility of the resins was lost and mechanical properties such as elongation were sometimes reduced.
Although the details are unknown, in the photosensitive resin composition of this embodiment, the polyfunctional (meth)acrylate compound (B) becomes intricately entangled with the polyimide resin (A) during curing (polymerization). , it is thought that a cured film different from the conventional cured film is formed. This "entangled structure of polyimide resin and polyfunctional (meth)acrylate" is thought to be related to good heat resistance and good mechanical properties.

When a polyfunctional (meth)acrylate compound (B) is used, the elongation of the resulting photosensitive resin composition is improved as described above, but on the other hand, swelling of the cured area and non-uniformity of the unexposed area may occur. There was a possibility that poor dissolution (bridging) due to excessive dissolution or a phenomenon in which unexposed areas remained undissolved (foot) could occur. Due to the occurrence of these defects, there is a possibility that a sufficient focus margin cannot be obtained.
As a result of studies by the present inventors, it has been found that by using the photosensitizer (C) and the polymerization inhibitor (D), it is possible to achieve both good elongation and good focus margin. By using the photosensitive agent (C), the photosensitive resin composition of this embodiment has improved curability in exposed areas, and can suppress the occurrence of bridging during the development process while maintaining good mechanical properties. . Furthermore, by using the polymerization inhibitor (D), the photosensitive resin composition of this embodiment improves the solubility of the unexposed area, and suppresses the formation of feet during the development process 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 simultaneously using the photosensitizer (C) and the polymerization inhibitor (D) and highly controlling their ratio, the cured film of the photosensitive resin composition of this embodiment has good elongation properties. It is possible to achieve both a good focus margin and a good focus margin.

From the above points, the photosensitive resin composition of this embodiment is preferably used for forming an insulating layer in an electronic device or an optical device.

The description will continue regarding components that can be contained in the photosensitive resin composition of this embodiment, properties, physical properties, etc. of the photosensitive resin composition of this embodiment.

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

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

As already mentioned, the photosensitive resin composition of this embodiment tends to shrink less due to curing (heating) by using a polyimide resin containing a ring-closed imide structure represented by 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 rate represented by is preferably 90% or more, more preferably 95% or more, and still more preferably 98% or more. In short, the polyimide resin (A) is preferably a resin that has no or few ring-opened amide structures and many ring-closed 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 determined, for example, from the area of a peak corresponding to an amide group or the area of a peak corresponding to an imide group in an NMR spectrum. As another example, the imidization rate can be determined from the area of a peak corresponding to an amide group or the area of a peak corresponding to an imide group in an infrared absorption spectrum.

It is preferable that the polyimide resin (A) 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 fluorine atoms, it is easy to make the photosensitive resin composition have a varnish-like property.
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, and more preferably 5 to 25% by mass. By containing a certain amount of fluorine atoms in the polyimide resin, it is easy to obtain sufficient solubility in organic solvents. 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 the ends of the polyimide resin (A) in various ways, 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 capable of reacting with an epoxy group to form a bond at its terminal end. Examples of such groups include acid anhydride groups, hydroxy groups, amino groups, and carboxy groups.

Preferably, the polyimide resin (A) has an acid anhydride group at its terminal. 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" here is preferably a 5-membered ring or a 6-membered ring, more preferably a 5-membered ring.

Here, in the structural unit represented by the general formula (a) constituting 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 improve 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 bonded via a single bond or a divalent linking group. Examples of the divalent linking group here include an alkylene group, a fluorinated alkylene group, and an ether group. The alkylene group and fluorinated alkylene group may be linear or branched.
The divalent organic group of X has, for example, 6 to 30 carbon atoms.
The number of carbon atoms in the tetravalent organic group of Y is, for example, 6 to 20.
It is preferable that each of the two imide rings in general formula (a) is a 5-membered ring.

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

It is more preferable that the polyimide resin (A) contains a structural unit represented by the following general formula (aa).

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

Typically, the polyimide resin (A) is produced by (i) first reacting diamine and acid dianhydride (condensation polymerization) to synthesize a polyamide, and (ii) then imidizing the polyamide (ring closure). (iii) introducing a desired functional group to the end of the polymer as necessary. For specific reaction conditions, reference may be made to the Examples listed below, the description in Patent Document 1 listed above, and the like.

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

Examples of raw material diamines include 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 raw acid dianhydrides 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 Examples include (3,4-phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane (6FDA). Of course, usable acid dianhydrides are not limited to these. One type or two or more types of acid dianhydrides can be used.

The ratio of diamine and acid dianhydride used is basically 1:1 in molar ratio. However, one may be used in excess in order 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, by using an excessive amount of acid dianhydride, the ends (both ends) of the polyimide resin (A) tend to become acid anhydride groups. As mentioned above, in this embodiment, the polyimide resin (A) preferably has an acid anhydride group at its terminal. Therefore, in this embodiment, it is preferable to use an excess amount of acid dianhydride when synthesizing the polyimide resin (A).

The terminal amino group and/or acid anhydride group of the polyimide obtained by condensation polymerization may be reacted with a certain reagent so that the terminal end of the polyimide has a desired functional group.

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 a certain extent, sufficient heat resistance of the cured film can be obtained, for example. Moreover, since the weight average molecular weight of the polyimide resin (A) is not too large, it becomes easy to dissolve the polyimide resin (A) in an 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). Examples of the polyfunctional (meth)acrylate compound (B) include those having two or more (meth)acryloyl groups in one molecule 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 strong cured film with good chemical resistance, the polyfunctional (meth)acrylate compound (B) is , preferably trifunctional or more. Although there is no particular upper limit to the number of functional groups in the polyfunctional (meth)acrylate compound (B), the upper limit to the number of functional groups is, for example, 11 functional groups due to ease of obtaining raw materials.
As a general tendency, 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 a 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 good.

As an example, the polyfunctional (meth)acrylate compound (B) preferably includes a tri- to tetrafunctional (meth)acrylate compound (B1).

As an example, the polyfunctional (meth)acrylate compound (B) preferably includes a (meth)acrylate compound (B2) having five or more functionalities.

As an example, the polyfunctional (meth)acrylate compound (B) can include a compound represented by the following general formula (b). In the following general formula, 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, the polyfunctional (meth)acrylate compound (B) is 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, epoxy acrylates such as di(meth)acrylate of bisphenol A diglycidyl ether, di(meth)acrylate of hexanediol diglycidyl ether, and polyisocyanates. Urethane (meth)acrylate, etc. obtained by reaction of hydroxyl group-containing (meth)acrylate 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 DPCA6 0, 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, NK Ester A-DPH (manufactured by Shin-Nakamura Chemical Co., Ltd.) and other commercially available products.

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 polyfunctional (meth)acrylate compounds (B) having different numbers of functional groups together. 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 thought that it will be possible.
Incidentally, among the 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) relative 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, and even more preferably It is 80 to 95 parts by mass.
Although the amount of the polyfunctional (meth)acrylate compound (B) used is not particularly limited, one or more of the various performances can be further improved by appropriately adjusting the amount used as described above. As mentioned above, in the photosensitive resin composition of this embodiment, it is thought that "an entangled structure of polyimide having a cyclic structure and polyfunctional (meth)acrylate" is formed by curing, but the polyimide resin (A ) By appropriately adjusting the amount of the polyfunctional (meth)acrylate compound (B) used, the polyimide resin (A) and the polyfunctional (meth)acrylate compound (B) are sufficiently entangled, and do not participate in the entanglement. It is thought that the amount of unnecessary components will be reduced, and as a result, the performance will be further improved.

(Photosensitizer (C))
The photosensitive resin composition of this embodiment contains a photosensitizer (C). The photosensitizer (C) is not particularly limited as long as it is capable of curing the photosensitive resin composition by generating active species when exposed to light.

The photosensitizer (C) preferably contains a photoradical generator. The photoradical generator is particularly effective in 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-ethoxycarboxinylnaphthyl)-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 and other biimidazole compounds; 1,2-octanedione, 1-[4-(phenylthio)phenyl]-2-( Oxime ester compounds such as ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(O-acetyloxime); Titanocene compounds such as (η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl) titanium; Acyls 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; and the like. Among these, oxime ester compounds can be particularly preferably used.

The photosensitive resin composition may contain only one kind of photosensitizer (C), or may contain two or more kinds.
The content of the photosensitizer (C) is, for example, 5 parts by mass or more and 30 parts by mass or less, and preferably 10 parts by mass or more and 25 parts by mass or less, based on 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, examples of the polymerization inhibitor (D) include hindered phenol compounds, hindered amine compounds, N-oxyl compounds, and thioether compounds. Among these, it is preferable to contain one or more selected from hindered phenol compounds, hindered amine compounds, and N-oxyl compounds 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] (Irganox1010), 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] (Irganox1035), 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-hexanediolbis[3-(3,5-di-tert) -butyl-4-hydroxyphenyl)propionate], 2,6-di-tert-butyl-4-cresol, 2,4-bis[(dodecylthio)methyl]-6-methylphenol (Irganox1726), 2,4-bis (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 Mixed ester with 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,2,3,4-butane Tetracarboxylic acid and 2,2,6,6-tetramethyl-4-piperidinol and 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5 .5] Mixed esterified product 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, reaction product of 2,2,6,6-tetramethylpiperidin-4-ylhexadecanoate and 2,2,6,6-tetramethylpiperidin-4-yl octadecanoate, etc. can be mentioned. These may be used alone or in combination of two or more.

Examples of N-oxyl compounds include 4-benzoyloxy-2,2,6,6-tetramethylpiperidinooxyl (4-benzoyloxyTEMPO), N-nitrosodiphenylamine, and N-nitroso-N-phenylhydroxylamine. , 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO), 4-hydroxy-2,2,6,6-tetramethylpiperidi-1-oxyl free radical (4-hydroxyTEMPO), sebacin Examples include acid bis(2,2,6,6-tetramethyl-4-piperidyl-1-oxyl) (sebacic acid bisTEMPO). These may be used alone or in combination of two or more.

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 alone or in combination of two or more.

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 part by mass or less. It is not less than 3 parts by mass and not 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 will improve, and the phenomenon of the unexposed area remaining undissolved in the development process (footprint) while maintaining good mechanical properties. ) 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 photosensitizer (C) is preferably 1 part by mass or more and 30 parts by mass or less, more preferably 5 parts by mass or less. It is not less than 20 parts by mass and not more than 20 parts by mass. If the content of the polymerization inhibitor (D) with respect to 100 parts by mass of the photosensitizer (C) is within the above range, the cured film of the photosensitive resin composition of this embodiment will have good elongation properties and a good focus margin. It is possible to achieve both.

(Thermal radical generator (E))
The photosensitive resin composition of this 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, etc.) of the cured film can be enhanced. This is considered to be because the use of the thermal radical generator (E) further promotes the polymerization reaction of the polyfunctional (meth)acrylate compound (B).

The thermal radical generator (E) preferably contains an organic peroxide. Examples of 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, dichloride Examples include milperoxide, t-butyl perbenzoate, parachlorobenzoyl peroxide, cyclohexanone peroxide, and the like.

When using a thermal radical generator (E), only one thermal radical generator (E) may be used, or two or more thermal radical generators (E) may be used.
When using the thermal radical generator (E), 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, based on 100 parts by mass of the polyimide resin (A). It is as follows.

(Crosslinking agent (F))
The photosensitive resin composition of this embodiment preferably contains a crosslinking agent (F). By using the crosslinking agent (F), for example, the crosslinking agent (F) and other components contained in the photosensitive resin composition will react, or the crosslinking agents (F) will polymerize with each other. (F) becomes closely intertwined 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 crosslinking agent (F) preferably has one epoxy-containing group at one end and one (meth)acryloyl group at the other end in the molecule. By having this configuration, the number of unreacted functional groups is reduced, and as a result, the chemical resistance and extensibility of the resin film made of the cured product of the photosensitive resin composition are improved.

In this embodiment, the "epoxy-containing group" refers to a substituent having oxacyclopropane (oxirane), which is a three-membered ring ether, in its structural formula. Specific examples include epoxy groups, glycidyl groups, and glycidyl ether groups, as well as organic groups in which one or more hydrogen atoms are converted into epoxy groups, glycidyl groups, or glycidyl ether groups (groups obtained by removing hydrogen from the OH group of glycidol). Examples include substituted groups, and specific examples include a 1,2-epoxycyclohexyl group. The organic group is not particularly limited, but includes, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group. Alkyl groups such as heptyl, octyl, nonyl and decyl groups; alkenyl groups such as allyl, pentenyl and vinyl groups; alkynyl groups such as ethynyl; alkylidene groups such as methylidene and ethylidene groups; phenyl groups , naphthyl group, anthracenyl group; aralkyl group such as benzyl group, phenethyl group; alkaryl group such as tolyl group, xylyl group; or cycloalkyl group such as adamantyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, etc. can be mentioned.

It is preferable that the crosslinking agent (F) contains a compound represented by general formula (1).

In general formula (1),
X ₁ represents a (meth)acryloyl group. X ₂ 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 from 1 to 10.

By selecting X ₂ from the above-mentioned functional groups, the reactivity between the crosslinking agent (F) and other components contained in the photosensitive resin composition or between the crosslinking agents (F) becomes good, and the reactivity of the photosensitive resin composition is improved. This is preferable because it improves the chemical resistance and extensibility of the resin film made of the cured product.

Furthermore, it is preferable for n to be within the range of 1 to 10 because the elongation rate of the resin film made of the cured product of the photosensitive resin composition becomes more suitable.

The crosslinking agent (F) preferably contains one or more compounds selected from any one of the following chemical formulas (2) to (4) as the compound satisfying the above general formula (1). By containing one or more compounds selected from any of the following chemical formulas (2) to (4), the chemical resistance and elongation rate of the resin film made of the cured product of the photosensitive resin composition are increased. A balance can be achieved.

The content of the crosslinking agent (F) is, for example, 0.1 part by mass or more, preferably 0.5 part by mass or more, and more preferably 1 part by mass or more based on 100 parts by mass of the polyimide resin (A). . When the content of the crosslinking agent (F) is 0.1 parts by mass or more, the cured product of the photosensitive resin composition can have high chemical resistance.
Further, the content of the crosslinking agent (F) is, for example, 30 parts by mass or less, preferably 20 parts by mass or less, and more preferably 10 parts by mass or less, based on 100 parts by mass of the polyimide resin (A). When the content of the crosslinking 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 rate of the cured product of the photosensitive resin composition is improved. In addition, the adhesion between the photosensitive resin composition and the substrate is sufficiently improved.

The photosensitive resin composition of this embodiment may contain only one type of crosslinking agent (F), or may contain two or more types of crosslinking agent (F).

(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 improved.

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

Examples of amino group-containing silane coupling agents include bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ-aminopropylmethyldiethoxy. Silane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-amino Examples include propylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane, and N-phenyl-γ-amino-propyltrimethoxysilane.
Examples of the epoxy group-containing silane coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidyl Examples include propyltrimethoxysilane.
Examples of (meth)acryloyl group-containing silane coupling agents include γ-((meth)acryloyloxypropyl)trimethoxysilane, γ-((meth)acryloyloxypropyl)methyldimethoxysilane, γ-((meth) Examples include acryloyloxypropyl)methyldiethoxysilane.
Examples of the mercapto group-containing silane coupling agent include 3-mercaptopropyltrimethoxysilane.
Examples of the vinyl group-containing silane coupling agent include vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, and vinyltrimethoxysilane.
Examples of the ureido group-containing silane coupling agent include 3-ureidopropyltriethoxysilane.
Examples of the sulfide group-containing silane coupling agent include bis(3-(triethoxysilyl)propyl)disulfide, bis(3-(triethoxysilyl)propyl)tetrasulfide, and the like.
Examples of the silane coupling agent having a cyclic anhydride structure include 3-trimethoxysilylpropylsuccinic anhydride, 3-triethoxysilylpropylsuccinic anhydride, 3-dimethylmethoxysilylpropylsuccinic anhydride, and the like. It will 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 easily reacts with the main chain, side chain, and/or terminal of the polyimide resin (A), and therefore a particularly good effect of improving adhesion can be obtained.

When a 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 weight, preferably 0.3 to 15 parts by weight, based on 100 parts by weight of the polyimide resin (A). parts, more preferably 0.4 to 12 parts by weight, still more preferably 0.5 to 10 parts by weight.

(Curing catalyst (H))
The photosensitive resin composition of this embodiment preferably contains a curing catalyst (H). This curing catalyst (H) has the function of promoting the reaction of the crosslinking agent (F). By using the curing catalyst (H), the reaction involving the crosslinking agent (F) can proceed sufficiently, and for example, the tensile elongation rate of the cured film can be further improved.

As the curing catalyst (H), mention may be made of compounds known as curing catalysts (often also called curing accelerators) for epoxy resins. For example, diazabicycloalkenes and their derivatives such as 1,8-diazabicyclo[5,4,0]undecene-7; amine compounds such as tributylamine and benzyldimethylamine; imidazole compounds such as 2-methylimidazole; triphenyl Organic phosphines such as phosphine and methyldiphenylphosphine; tetraphenylphosphonium/tetraphenylborate, tetraphenylphosphonium/tetrabenzoic acid borate, tetraphenylphosphonium/tetranaphthoic acid borate, tetraphenylphosphonium/tetranaphthoyloxyborate, tetraphenyl Tetra-substituted phosphonium salts such as phosphonium tetranaphthyloxyborate and tetraphenylphosphonium 4,4'-sulfonyldiphenolate; triphenylphosphine adducted with benzoquinone, and the like. Among them, organic phosphines are preferred.

When using the curing catalyst (H), the amount thereof is, for example, 1 to 80 parts by weight, preferably 2 to 50 parts by weight, and more preferably 3 to 30 parts by weight, based on 100 parts by weight of the crosslinking agent (F). .

(Surfactant (I))
The photosensitive resin composition of this embodiment preferably contains surfactant (I). This can further improve the coating properties of the photosensitive resin composition and the flatness of the film.
Examples of the surfactant (I) include fluorine surfactants, silicone surfactants, alkyl surfactants, and acrylic surfactants.
As another aspect, the surfactant is preferably nonionic. The use of a nonionic surfactant is preferable, for example, in that it suppresses unintentional reactions with other components in the composition and improves the storage stability of the composition.

The 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 (improving coating properties), improving developability, and improving adhesive strength. As such a surfactant, for example, a nonionic surfactant containing at least one of a fluorine atom and a silicon atom is preferable. Commercially available products that can be used as surfactant (I) include, for example, F-251, F-253, F-281, F-430, F-477, and F-251, F-253, F-281, F-430, F-477, and F-253 of the "Megafac" series 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 etc., fluorine-containing nonionic surfactants such as Ftergent 250 and Ftergent 251 manufactured by Neos Co., Ltd., SILFOAM (registered trademark) series manufactured by Wacker Chemie (e.g. Examples include silicone surfactants such as SD 100 TS, SD 670, SD 850, SD 860, and SD 882).
Further, FC4430 and FC4432 manufactured by 3M Corporation can also be mentioned as preferred surfactants.

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

(Solvent (J)/Properties 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 of the above-mentioned components 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, and 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, etc. . These may be used alone or in combination.

When the photosensitive resin composition of this embodiment contains the solvent (J), the photosensitive resin composition of this embodiment is usually varnish-like. More specifically, the photosensitive resin composition of the present embodiment is preferably a varnish-like composition in which at least a polyimide resin (A) and a polyfunctional (meth)acrylate compound (B) are dissolved in a solvent (J). It is a composition. Since the photosensitive resin composition of this embodiment is varnish-like, it is possible to form a uniform film by coating. Furthermore, 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 using the solvent (J), 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 be fully dissolved or dispersed. In addition, good coating properties can be ensured, which in turn leads to improved flatness during spin coating. Furthermore, by adjusting the content of nonvolatile components, the viscosity of the photosensitive resin composition can be appropriately controlled.
As another aspect, the proportion 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 certain 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 above-mentioned components, the photosensitive resin composition of the present embodiment may contain components other than the above-mentioned components, if necessary. Examples of such components include 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 of this embodiment is as follows:
a film forming step of forming a photosensitive resin film on the substrate using the above photosensitive resin composition;
an exposure step of exposing the photosensitive resin film;
a development step of developing the exposed photosensitive resin film;
including.
Moreover, it is preferable that the manufacturing method of the electronic device of this embodiment includes the thermosetting process of heating and hardening the exposed photosensitive resin film after the above-mentioned image development process. Thereby, a cured film with sufficient heat resistance can be obtained.
In the manner described above, an electronic device including a cured film of the photosensitive resin composition of this embodiment can be manufactured.

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

FIG. 1 is a longitudinal cross-sectional view showing an example of an electronic device according to this embodiment. Moreover, FIG. 2 is a partially enlarged view of the area surrounded by the chain line in FIG.
In the following description, the upper side in FIG. 1 will be referred to as "upper" and the lower side will be referred to as "lower".

An 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 top surface to the bottom surface of the insulating layer 21 , a semiconductor chip 23 embedded inside the insulating layer 21 , and a semiconductor chip 23 provided on the bottom surface of the insulating layer 21 . A lower wiring layer 24 , 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 .

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

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

In such an electronic device 1, since there is no need 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 miniaturization of electronic equipment incorporating the electronic device 1.

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

Hereinafter, the through electrode substrate 2 and the semiconductor package 3 will be explained in further detail.
The lower wiring layer 24 and the upper wiring layer 25 included 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 via the through wiring 221 that penetrates the insulating layer 21.

The wiring layers included in the lower wiring layer 24 are connected to the semiconductor chip 23 and the solder bumps 26. Therefore, the lower wiring layer 24 functions as a rewiring layer of 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 through the insulating layer 21, as described above. Thereby, 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, so that the electronic device 1 can be highly functional. can.

The wiring layer 253 included in the upper wiring layer 25 shown in FIG. 2 is connected to the through wiring 221 and the solder bumps 35. Therefore, the upper wiring layer 25 is electrically connected to the semiconductor chip 23 and functions as a rewiring layer for the semiconductor chip 23 and as an interposer interposed between the semiconductor chip 23 and the package substrate 31. also works. The cured film of the photosensitive resin composition of this embodiment can be used to constitute the insulating layer of the rewiring layer.

According to the present 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 the present embodiment. It is possible to realize an electronic device composed of a cured product of a polyurethane resin composition.

By penetrating the insulating layer 21 with the through wiring 221, the effect of reinforcing the insulating layer 21 can be obtained. Therefore, even if the lower wiring layer 24 and the upper wiring layer 25 have low mechanical strength, the mechanical strength of the through electrode substrate 2 as a whole can be prevented from decreasing. As a result, it is possible to further reduce the thickness of the lower wiring layer 24 and the upper wiring layer 25, and it is possible to further reduce the height of the electronic device 1.

In addition to the through wiring 221, the electronic device 1 shown in FIG. 1 also includes a through wiring 222 provided to penetrate the insulating layer 21 located on the upper surface of the semiconductor chip 23. 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 to cover the semiconductor chip 23. This increases the effect of protecting the semiconductor chip 23. As a result, the reliability of the electronic device 1 can be improved. Moreover, the electronic device 1 can be easily applied to a mounting method such as the package-on-package structure according to this 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 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 type 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 P ackage), SON (Small Outline Non-leaded Package), Examples include LF-BGA (Lead Flame BGA) and the like.

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 packaging density is increased. Note that the plurality of semiconductor chips 32 may be arranged side by side in the plane direction, or may be stacked in the thickness direction and arranged side by side in the plane direction.

The package substrate 31 may be any type of substrate, but may include, for example, an insulating layer, a wiring layer, a through wiring, etc. (not shown). Among these, the solder bumps 35 and the bonding wires 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 bonding wires 33 can be protected from external forces and the external environment.

The semiconductor chip 23 included in the through electrode substrate 2 and the semiconductor chip 32 included in the semiconductor package 3 are arranged close to each other. This makes it possible to enjoy benefits such as faster mutual communication and lower loss. From this viewpoint, for example, one of the semiconductor chips 23 and 32 is used as an arithmetic element such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or an AP (Application Processor), and the other is used as a DRAM (Dynamic RAM). c Random Access By using storage elements such as memory (Memory) or flash memory, these elements can be placed close to each other in the same device. Thereby, it is possible to realize an electronic device 1 that is both highly functional and compact.

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

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

The manufacturing method of the electronic device 1 includes a chip placement step S1 in which the insulating layer 21 is obtained so as to embed the semiconductor chip 23 provided on the substrate 202 and the through wirings 221 and 222, and an upper layer is formed on the insulating layer 21 and the semiconductor chip 23. An upper wiring layer forming step S2 for forming the wiring layer 25, a substrate peeling step S3 for peeling off the substrate 202, a lower wiring layer forming step S4 for forming the lower wiring layer 24, forming the solder bumps 26, and forming the through electrode substrate. 2, and a stacking step S6 of stacking the semiconductor package 3 on the through electrode substrate 2.

Among these, in the upper wiring layer forming step S2, a photosensitive resin varnish 5 (varnish-like photosensitive resin composition) is placed on the insulating layer 21 and the semiconductor chip 23, and a first resin is used to form the photosensitive resin layer 2510. A film arrangement step S20, a first exposure step S21 in which the photosensitive resin layer 2510 is exposed to light, a first development step S22 in which the photosensitive resin layer 2510 is developed, and a curing treatment is performed on the photosensitive resin layer 2510. A first curing step S23, a wiring layer forming step S24 of forming the wiring layer 253, and a second resin step in which the photosensitive resin varnish 5 is placed on the photosensitive resin layer 2510 and the wiring layer 253 to obtain the photosensitive resin layer 2520. A film arrangement step S25, a second exposure step S26 in which the photosensitive resin layer 2520 is exposed to light, a second development step S27 in which the photosensitive resin layer 2520 is developed, and a curing treatment is performed on the photosensitive resin layer 2520. The process includes a second curing step S28 and a through wiring forming step S29 in which the through wiring 254 is formed in the opening 424 (through hole).

Each step will be explained in sequence below. The following manufacturing method is an example, and is not limited thereto.

[1] Chip placement process S1
First, as shown in FIG. 4A, a chip includes a substrate 202, a semiconductor chip 23 and through wirings 221 and 222 provided on the substrate 202, and an insulating layer 21 provided to embed these. An embedded structure 27 is prepared.

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

The semiconductor chip 23 is bonded onto the substrate 202. In this manufacturing method, for example, a plurality of semiconductor chips 23 are placed on the same substrate 202 while being spaced apart 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.

If necessary, an interposer (not shown) may be provided between the substrate 202 and the semiconductor chip 23. The interposer functions as a rewiring layer for the semiconductor chip 23, for example. Therefore, the interposer may include pads (not shown) for electrical connection with electrodes of the semiconductor chip 23, which will be described later. Thereby, 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 increased.
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, etc. are used as the interposer.

The insulating layer 21 may be, for example, a resin film (organic insulating layer) containing a thermosetting resin or a thermoplastic resin as mentioned as a component of the photosensitive resin composition, or a general sealing layer used in the semiconductor technical field. It may also be a stopper.

Examples of the constituent material of the through wirings 221 and 222 include copper or a copper alloy, aluminum or an aluminum alloy, gold or a gold alloy, silver or a silver alloy, nickel or a nickel alloy, and the like.

Note that the chip-embedded structure 27 may be prepared using a method different from that described above.

[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 arrangement step S20
First, as shown in FIG. 4(b), photosensitive resin varnish 5 is applied (disposed) on the insulating layer 21 and the semiconductor chip 23. As shown in FIG. 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.

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, and 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. 4(d)) can be formed. As a result, the upper wiring layer 25 can be made thinner, making it easier to make the electronic device 1 thinner.
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) at a rotation speed of 100 rpm.

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

The drying conditions for the photosensitive resin varnish 5 are not particularly limited, but include, for example, heating conditions 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 a photosensitive resin composition of this embodiment, and is a resin film having photosensitivity.

The photosensitive resin film is manufactured, for example, by applying 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, if 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 below, the adverse effects of heating on the photoacid generator can be minimized.

The temperature of the pre-exposure heat treatment is preferably 70 to 130°C, more preferably 75 to 120°C, and still more preferably 80 to 110°C. If the temperature of the pre-exposure heat treatment is below the lower limit, there is a possibility that the purpose of stabilizing molecules by the pre-exposure heat treatment will not be achieved. On the other hand, if the temperature of the pre-exposure heat treatment exceeds the upper limit, the movement of the photoacid generator becomes too active, resulting in the effect that it becomes difficult to generate acid even when light is irradiated in the first exposure step S21, which will be described later. There is a possibility that the patterning accuracy will decrease due to the wide range of patterning.

The time of the pre-exposure heat treatment is appropriately set depending on the temperature of the pre-exposure heat treatment, but at the above temperature it is preferably 1 to 10 minutes, more preferably 2 to 8 minutes, still more preferably 3 to 8 minutes. It is said to be 6 minutes. If the time for the pre-exposure heat treatment is less than the lower limit, the heating time will be insufficient, and there is a risk that the purpose of the pre-exposure heat treatment, which is stabilization of molecules, will not be achieved. On the other hand, if the pre-exposure heat treatment time exceeds the above upper limit, the heating time will be too long and the action of the photoacid generator will be inhibited even if the pre-exposure heat treatment temperature is within the above range. There is a risk of it getting lost.

The atmosphere for the heat treatment is not particularly limited. Although an inert gas atmosphere, a reducing gas atmosphere, etc. may be used, in consideration of work efficiency, etc., it is preferable to use the atmosphere.

Atmospheric pressure is not particularly limited. It may be under reduced pressure or increased pressure, but in consideration of work efficiency etc., normal pressure is used. Note that normal pressure refers to a pressure of about 30 to 150 kPa, preferably atmospheric pressure.

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

First, as shown in FIG. 4(d), a mask 412 is placed in a predetermined area on the photosensitive resin layer 2510. Then, light (active radiation) is irradiated through the mask 412. Thereby, exposure processing is performed on the photosensitive resin layer 2510 according to the pattern of the mask 412.

FIG. 4D shows a case where the photosensitive resin layer 2510 has so-called negative photosensitivity. In this example, a region of the photosensitive resin layer 2510 corresponding to the light-blocking portion of the mask 412 is dissolved in the developer.

On the other hand, active chemical species are generated from the photosensitizer (C) in a region corresponding to the transparent portion of the mask 412. The active species acts as a catalyst for the curing reaction.

The amount of exposure in the exposure process is not particularly limited. 100 to 2000 mJ/cm ² is preferable, and 200 to 1000 mJ/cm ² is more preferable. Thereby, underexposure and overexposure in the photosensitive resin layer 2510 can be suppressed. As a result, high patterning accuracy can finally be achieved.
Thereafter, 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. The temperature is preferably 50 to 150°C, more preferably 50 to 130°C, even more preferably 55 to 120°C, particularly preferably 60 to 110°C. By performing the post-exposure heat treatment at such a temperature, the catalytic action of the generated acid is sufficiently enhanced, and the thermosetting resin can be reacted sufficiently in a shorter time. By controlling the temperature within the above range, it is possible to suppress deterioration in patterning accuracy due to promotion of acid diffusion.
By setting the temperature of the post-exposure heat treatment to the above lower limit or higher, the reaction rate of the thermosetting resin can be increased and productivity can be increased. On the other hand, by controlling the temperature of the post-exposure heat treatment to be equal to or lower than the above upper limit, it is possible to suppress a decrease in patterning accuracy due to promotion of acid diffusion.

The time for the post-exposure heat treatment is appropriately set depending on the temperature of the post-exposure heat treatment. At the above temperature, the heating time is preferably 1 to 30 minutes, more preferably 2 to 20 minutes, and even more preferably 3 to 15 minutes. By performing the post-exposure heat treatment for such a period of time, the thermosetting resin can be sufficiently reacted, and the diffusion of acid can be suppressed, thereby suppressing a decrease in patterning accuracy.

The atmosphere for the post-exposure heat treatment is not particularly limited. Although an inert gas atmosphere, a reducing gas atmosphere, etc. may be used, in consideration of work efficiency, etc., it is preferable to use the atmosphere.

The atmospheric pressure for the post-exposure heat treatment is not particularly limited. It may be under reduced pressure or increased pressure, but in consideration of work efficiency etc., normal pressure is used. Thereby, the pre-exposure heat treatment can be performed relatively easily. Note that normal pressure refers to a pressure of about 30 to 150 kPa, preferably atmospheric pressure.

[2-3] First development step S22
Next, the photosensitive resin layer 2510 is subjected to a development process. As a result, an opening 423 penetrating the photosensitive resin layer 2510 is formed in a region corresponding to the light-shielding portion of the mask 412 (see FIG. 5E).

Examples of the developer include organic developers, water-soluble developers, and 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 components 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 when developing with an alkaline developer (aqueous). In other words, it is easier to obtain a finer pattern.

Specifically, 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 may be used, which consists only of an organic solvent and does not contain any impurities other than unavoidable impurities. Impurities that are unavoidably included include metal elements and water, but from the viewpoint of preventing contamination of electronic devices, it is better to have fewer impurities that are unavoidably included.

The method of bringing the developer into contact with the photosensitive resin layer 2510 is not particularly limited. Generally known methods such as a dipping method, a paddle method, and a spray method can be applied as appropriate.

The time for the developing step is usually in the range of about 5 to 300 seconds, preferably about 10 to 120 seconds, and is appropriately adjusted based on the 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). The conditions of 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. Thereby, the photosensitive resin layer 2510 can be cured and the organic insulating layer 251 can be obtained while suppressing the thermal influence 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. 5(f)). The wiring layer 253 is formed by obtaining a metal layer using a vapor phase film forming method such as a sputtering method or a vacuum evaporation method, and then patterning the metal layer 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 arrangement step S25
Next, as shown in FIG. 5(g), a photosensitive resin layer 2520 is obtained in the same manner as in the first resin film arrangement step S20. The photosensitive resin layer 2520 is arranged to cover the wiring layer 253.
Thereafter, if necessary, the photosensitive resin layer 2520 is subjected to pre-exposure heat treatment. 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 to light. The processing conditions are, for example, the conditions described in the first exposure step S21.
Thereafter, the photosensitive resin layer 2520 is subjected to post-exposure heat treatment, if necessary. 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 subjected to a development process. The processing conditions are, for example, the conditions described in the first development step S22. As a result, an opening 424 passing through the photosensitive resin layers 2510 and 2520 is 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, and an organic insulating layer 252 is obtained (see FIG. 6(i)).

In this embodiment, the upper wiring layer 25 has two layers, the organic insulating layer 251 and the organic insulating layer 252, but 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 repeatedly added.

[2-10] Through-hole wiring formation step S29
Next, a through wiring 254 shown in FIG. 6(i) is formed in the opening 424.

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

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

Next, a resist layer (not shown) is formed on a region other than the opening 424 of the seed layer (not shown). Then, using this resist layer as a mask, the opening 424 is filled with metal. For example, electrolytic plating is used for this filling. Examples of the metal to be filled include copper or a copper alloy, aluminum or an aluminum alloy, gold or a gold alloy, silver or a silver alloy, nickel or a nickel alloy. In this way, the conductive material is buried in the opening 424, and the through wiring 254 is formed.

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

[3] Substrate peeling process 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. The lower wiring layer 24 may be formed by any method, for example, 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 forming step S5
Next, as shown in FIG. 6(l), solder bumps 26 are formed on the lower wiring layer 24. Further, 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.
In the manner described above, the through electrode substrate 2 is obtained.

The through electrode substrate 2 shown in FIG. 6(l) can be divided into a plurality of regions. Therefore, for example, by dividing the through electrode substrate 2 into pieces along the dashed line shown in FIG. 6(l), a plurality of through electrode substrates 2 can be efficiently manufactured. Note that, for example, a diamond cutter or the like can be used to separate the pieces into pieces.

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

This method of manufacturing the electronic device 1 can be applied to a wafer level process or a panel level process using a large-area substrate. Thereby, manufacturing efficiency of the electronic device 1 can be increased and costs 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 described above.

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, and CMOS. It can be used for a rewiring layer, an interlayer insulating film, a sealing material (top coat), etc. The photosensitive resin composition of this embodiment can be particularly suitably used 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, etc. will be described in more detail below with reference to the drawings.

(Film forming process: FIG. 7A) In the film forming process, a photosensitive resin film 73 is formed using the photosensitive resin composition of this embodiment on the side of the substrate 71 having the steps 710, which has the steps.
The substrate 71 is not particularly limited. Examples of the substrate 71 include a silicon wafer, a ceramic substrate, an aluminum substrate, a SiC wafer, and a GaN wafer.
The step 710 is, for example, 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 to 10 μm, preferably 1 to 5 μm.
The thickness of the photosensitive resin film 73 (the thickness of the portion without the step 710) is, for example, 1 to 15 μm, preferably 1 to 10 μm. This thickness may be greater than the height of the step 710.

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

After the film forming process and before the exposure process, it is preferable to heat and dry the photosensitive resin film 73. This heat drying is sometimes called "prebake."
The temperature for heat drying is usually 50 to 180°C, preferably 60 to 150°C. The heating drying time is usually about 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 performed using a hot plate, oven, or the like.

(Exposure process: Figure 7B)
In the exposure step, the photosensitive resin film 73 is exposed through the photomask 720. Examples of active light for exposure include X-rays, electron beams, ultraviolet rays, and visible light. In terms of wavelength, active light with a wavelength of 200 to 500 nm is preferred. In terms of pattern resolution and ease of handling the device, the light source is preferably a mercury lamp's g-line, h-line, or i-line. Furthermore, two or more light beams may be mixed and used.
As the exposure device, a contact aligner, a mirror projection, or a stepper is preferable.
The exposure amount in the exposure step is usually between 40 and 1500 mJ/cm ² , preferably between 80 and 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. Adjustments will be made as appropriate.

It is preferable to heat the resin film (post-exposure heating) between the exposure step and the development step. As a result, the reaction of substances (such as photosensitizers) that are cleaved and decomposed by exposure to light progresses, and improvement in pattern shape can be expected. The temperature and time for post-exposure heating are, for example, 50 to 200° C. and about 10 to 600 seconds.

(Developing process: Figure 7C)
In the development step, the photosensitive resin film exposed in the exposure step is developed using a developer. Thereby, a portion of the photosensitive resin film 73 can be removed to obtain the resin film 73A provided with the openings 75. The photosensitive resin composition of this embodiment is usually negative type. Therefore, an opening 75 is provided in a portion of the photomask 720 corresponding to the light shielding portion.
The developing step can be performed, for example, by a dipping method, a paddle 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 components 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 when developing with an alkaline developer (aqueous). In other words, it is easier to obtain a finer pattern.

Specifically, 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 may be used, which consists only of an organic solvent and does not contain any impurities other than unavoidable impurities. Note that impurities that are unavoidably included include metal elements, but from the viewpoint of preventing contamination of electronic devices, it is better to have fewer impurities that are unavoidably included.

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

For example, there may be a curing process for curing the resin film 73A between the development 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 this embodiment, the surface (upper surface) of the resin film 73A has good flatness even after such a curing step.

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

Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and the present invention includes modifications, improvements, etc. within a range that can achieve the purpose 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 present invention is not limited only to the embodiments.
In the following, "TEMPO" is an abbreviation for "2,2,6,6-tetramethylpiperidine-1-oxyl". Other abbreviations will be explained as appropriate in the text.

<Synthesis of polyimide resin>
(Synthesis of polyimide resin (A-1))
In a 5 L separable flask equipped with a stirrer and condenser, 304.2 g (0.95 mol) of 2,2'-bis(trifluoromethyl)benzidine (TFMB) and 4,4'-(hexafluoroisopropylidene) were added. ) 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 heated under nitrogen atmosphere at room temperature. A polymerization reaction was carried out by reacting for a period of time. Subsequently, the temperature of the reaction solution was raised to 180° C. in an oil bath, 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. The obtained solid was roughly filtered and further washed with isopropanol/water=4/7 to obtain a white solid of polyimide. The obtained 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. Furthermore, the imidization rate of the polyimide resin (A-1) as determined by NMR measurement was 98%.

(Synthesis of polyimide resin (A-2))
Into a 5 L separable flask equipped with a stirrer and a cooling tube, 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 heated at room temperature under nitrogen atmosphere for 16 hours. A polymerization reaction was carried out. Subsequently, the temperature of the reaction solution was raised to 180° C. in an oil bath, 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. The obtained solid was roughly filtered and further washed with isopropanol/water=4/7 to obtain a white solid of polyimide. The obtained white solid was vacuum-dried at 200° C. to obtain a polyimide resin (A-2) having an acid anhydride group at the terminal.
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) as determined by NMR measurement was 98%.

(Synthesis of polyimide resin (A-3))
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-(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 for 16 hours at room temperature under a nitrogen atmosphere to perform a polymerization reaction. Subsequently, the temperature of the reaction solution was raised to 180° C. in an oil bath, 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. The obtained solid was roughly filtered and further washed with isopropanol/water=4/7 to obtain a white solid of polyimide. The obtained white solid was vacuum-dried at 200° C. to obtain a polyimide resin (A-3) having an acid anhydride group at the terminal.
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) as determined by NMR measurement was 98%.

(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) and 4,4'-(hexafluoroisopropylidene) were added. ) 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 heated under nitrogen atmosphere at room temperature. A polymerization reaction was carried out by reacting for a period of time. Subsequently, the temperature of the reaction solution was raised to 180° C. in an oil bath, 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. The obtained solid was roughly filtered and further washed with isopropanol/water=4/7 to obtain a white solid of polyimide. The obtained white solid was vacuum-dried at 200° C. to obtain a polyimide resin (A-4) having an acid anhydride group at the terminal.
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) as determined by NMR measurement was 98%.

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

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., 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) Cyclomer 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'-sulfonyl diphenolate The method for synthesizing the curing catalyst (H-1) is as follows.
In a separable flask equipped with a stirrer, 37.5 g (0.15 mol) of 4,4'-bisphenol S and 100 mL of methanol were charged, stirred and dissolved at room temperature, and while stirring, 4.0 g of sodium hydroxide was added in advance to 50 mL of methanol. A solution containing 0 g (0.1 mol) was added. Next, a solution of 41.9 g (0.1 mol) of tetraphenylphosphonium bromide 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 with stirring to obtain a white precipitate. The precipitate was filtered and dried. A white crystal curing catalyst (H-1) was thus 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 phenol compound)
(D-2) Irganox 1010 (manufactured by BASF, hindered phenol 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 Kasei Kogyo Co., Ltd., hindered phenol compound)
(D-5) N,N-diphenylnitrosamide (manufactured by Tokyo Chemical Industry Co., Ltd., N-oxyl compound)
(D-6) Capferron (manufactured by Tokyo Chemical Industry Co., Ltd., N-oxyl compound)
(D-7) TEMPO (Tokyo Kasei Kogyo Co., Ltd., N-oxyl compound)
(D-8) 4-hydroxy TEMPO (manufactured by Seiko Kagaku Co., Ltd., N-oxyl compound)
(D-9) BisTEMPO sebacic acid (manufactured by Seiko Chemical Co., Ltd., N-oxyl compound)
(D-10) Irganox 1726 (manufactured by BASF, hindered phenol compound)
(D-11) Irganox 1520L (manufactured by BASF, hindered phenol compound)

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

<Evaluation of focus margin>
The photosensitive resin compositions of Examples and Comparative Examples were applied onto 12-inch plated copper (Ra=0.08 μm) wafers using a spin coater so that the film thickness after drying was 5 μm. Thereafter, it was dried on a hot plate at 120° C. for 3 minutes to obtain a photosensitive resin film.
This photosensitive resin film was passed through a photomask (on which a punched pattern of round vias with a diameter of 3 μm was drawn) and an i-line stepper (manufactured by CANON, FPA-5500iX, NA=0.28) was used to measure the exposure amount. I-ray irradiation was performed while changing the focus from 190 mJ to 550 mJ at a rate of 30 mJ/min and from −9 μm to +3 μm at a rate of 1 μm.
Thereafter, 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 developed film (negative pattern). Ta. Thereafter, 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. Through the above steps, a cured product of the photosensitive resin composition was obtained.
Within the above exposure range, the difference between the maximum and minimum focus values was calculated as the focus margin for a via hole of 3 μmΦ without foot or bridge formation, and the results are shown in Table 1. Described. In each Example and Comparative Example, when the focus margin can be calculated at a plurality of exposure doses, the value of the largest focus margin is described.

<Evaluation of tensile elongation rate>
(Creation of test piece for measuring tensile elongation rate)
The photosensitive resin composition was spin-coated onto an 8-inch silicon wafer so that the film thickness after drying was 10 μm, and then heated at 120° C. for 3 minutes to obtain a photosensitive resin film.
The obtained photosensitive resin film was exposed to light of 300 mJ/cm ² using a high-pressure mercury lamp. Thereafter, the exposed resin film and the silicon wafer were immersed in cyclopentanone for 30 seconds. Furthermore, after that, heat treatment was performed at 200° C. for 120 minutes in a nitrogen atmosphere. Through the above steps, a cured product of the photosensitive resin composition was obtained.
The obtained cured product was cut with a dicing saw along with the silicon wafer to a width of 5 mm, and then peeled off from the substrate by immersing it in a 2% by mass hydrofluoric acid aqueous solution. The peeled film was dried at 60° C. for 10 hours to obtain a test piece (30 mm x 5 mm x 10 μm thick).

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

Table 1 shows the formulation 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 properties.

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 Through 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 Penetrating wiring 222 Penetrating wiring 231 Land 240 Organic insulating layer 241 Organic insulating layer 242 Organic insulating 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 process S2 Upper wiring layer formation process S20 First resin film placement process S21 First exposure process S22 First development process S23 First curing process S24 Wiring layer formation process S25 Second resin film placement process S26 Second exposure process S27 Second development step S28 Second curing step S29 Penetrating wiring forming step S3 Substrate peeling step S4 Lower wiring layer forming step S5 Solder bump forming step S6 Lamination step W Diameter

Claims (23)

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,
Photosensitive resin composition. The photosensitive resin composition according to claim 1,
The number of moles of imide groups contained in the polyimide resin (A) is IM,
When the number of moles of amide groups contained in the polyimide resin (A) is AM,
A photosensitive resin composition having an imidization rate expressed by {IM/(IM+AM)}×100(%) of 90% or more. 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) includes a tri- to tetrafunctional (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) includes a (meth)acrylate compound (B2) having five or more functionalities. 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) based on 100 parts by mass of the polyimide resin (A) is 25 parts by mass or more and 100 parts by mass or less. The photosensitive resin composition according to any one of claims 1 to 6,
A photosensitive resin composition, wherein the photosensitizer (C) contains a photoradical generator. The photosensitive resin composition according to claim 7,
A photosensitive resin composition, wherein the photo-radical generator includes 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 photosensitizer (C) based on 100 parts by mass of the polyimide resin (A) is 5 parts by mass or more and 30 parts by mass or less. 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,
A photosensitive resin composition, wherein the content of the polymerization inhibitor (D) based on 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,
A photosensitive resin composition in which the content of the polymerization inhibitor (D) based on 100 parts by mass of the photosensitizer (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,
Furthermore, a photosensitive resin composition containing a thermal radical generator (E). The photosensitive resin composition according to any one of claims 1 to 13,
A photosensitive resin composition further containing a crosslinking agent (F). The photosensitive resin composition according to claim 14,
A photosensitive resin composition in which the crosslinking agent (F) contains a compound having one epoxy-containing group at one end and one (meth)acryloyl group at the other end in the molecule. The photosensitive resin composition according to any one of claims 1 to 15,
Furthermore, a photosensitive resin composition containing 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 insulating layers in electronic devices. 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, including: A method for manufacturing an electronic device according to claim 19, comprising:
A method for manufacturing an electronic device, including 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;
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. 23. The optical device according to claim 22, wherein the light emitting element is a micro LED.

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