JP7392580B2 - Photosensitive resin composition, electronic device manufacturing method, and electronic device - Google Patents

Description

The present invention relates to a photosensitive resin composition, a method for manufacturing an electronic device, and an electronic device. More specifically, the present invention relates to a photosensitive resin composition containing a polyamide resin and/or a polyimide resin, a method for manufacturing an electronic device using the photosensitive resin composition, and an electronic device that can be manufactured by the method for manufacturing an electronic 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

As electronic devices become more sophisticated and complex, electronic devices are required to be more reliable than ever before. Therefore, there is a need to improve the reliability of electronic devices by improving the cured film (improving the photosensitive resin composition for forming the cured film).
Furthermore, in recent years, in order to reduce thermal damage to semiconductor chips, there has been a demand for a relatively low heating temperature (for example, about 170° C.) when forming a cured film.

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 that can be cured by heating at about 170° C. to form a cured film, thereby making it possible to manufacture highly reliable electronic devices.

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

According to the present invention, the following photosensitive resin composition is provided.
A photosensitive resin composition containing a polyamide resin and/or a polyimide resin,
When the cured film obtained by heating the photosensitive resin composition at 170°C for 2 hours was subjected to dynamic viscoelasticity measurement under the following conditions, the storage modulus E' ₂₂₀ at 220°C was 0.5 to 0.5. A photosensitive resin composition having a pressure of 3.0 GPa.
[conditions]
Frequency: 1Hz
Temperature: 30-300℃
Heating rate: 5℃/min Measurement mode: Tensile mode

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.

By curing the photosensitive resin composition of the present invention by heating at about 170° C. to form a cured film, highly reliable electronic devices can be manufactured.

FIG. 2 is a diagram for explaining a method of manufacturing an electronic device. FIG. 2 is a diagram for explaining a method of manufacturing an electronic device. FIG. 2 is a diagram for explaining a method of manufacturing an electronic device.

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, or chemical battery. , devices, final products, etc.

<Photosensitive resin composition>
The photosensitive resin composition of this embodiment contains a polyamide resin and/or a polyimide resin.
When the cured film obtained by heating the photosensitive resin composition of this embodiment at 170°C for 2 hours was subjected to dynamic viscoelasticity measurement under the following conditions, the storage modulus E' ₂₂₀ at 220°C was as follows: It is 0.5 to 3.0 GPa.
[conditions]
Frequency: 1Hz
Temperature: 30-300℃
Heating rate: 5℃/min Measurement mode: Tensile mode

In the electronic device manufacturing process, a cured film may reach a high temperature due to various types of "heating" being performed.
The present inventors thought that the high temperature caused by heating may have an adverse effect on the cured film in the electronic device, resulting in a decrease in the reliability of the electronic device. More specifically, because the cured film changes/softens at high temperatures, for example, the adhesion between the cured film and the substrate decreases, causing peeling of the cured film, resulting in a decrease in the reliability of electronic devices. That's what I thought.

Based on this idea, the present inventors have discovered that it is possible to form a cured film that is difficult to soften (having a relatively large elastic modulus at ≒220°C) at a heating temperature of 220°C, which can be used as a heating temperature in a reflow process. We thought that if we could design a photosensitive resin composition, the decrease in adhesion of the cured film due to heating could be suppressed, and as a result, the reliability of electronic devices could be improved. We also thought that if such a cured film could be formed by heating at about 170° C., it would be possible to follow recent trends in electronic device manufacturing.

Taking this idea further, the present inventors determined that (i) the hardness of the cured film at 220°C as an index of the difficulty of softening the cured film at 220°C in photosensitive resin compositions containing polyamide resins and/or polyimide resins; The storage modulus E' ₂₂₀ was adopted, and (ii) a new photosensitive resin composition was designed whose E' ₂₂₀ was 0.5 GPa or more. Here, as the conditions for forming the cured film, "2 hours at 170° C." was adopted based on recent trends in electronic device manufacturing.
By applying this new photosensitive resin composition to electronic device manufacturing (for example, formation of an insulating layer in electronic devices), the present inventors succeeded in increasing the reliability of electronic devices.

Incidentally, in principle, it is considered that the larger E' ₂₂₀ is, the better, but from the viewpoint of cost and realistic composition design, in this embodiment, the upper limit of E' ₂₂₀ is set at 3.0 GPa. There is.
E' ₂₂₀ may be 0.5 to 3.0 GPa, preferably 0.6 to 2.5 GPa, more preferably 0.7 to 2.0 GPa.

The photosensitive resin composition of this embodiment having an E' ₂₂₀ of 0.5 GPa or more and 3.0 GPa or less can be manufactured by appropriately selecting materials, their formulations, preparation methods, and the like. Preferred materials for the photosensitive resin composition of this embodiment will be explained below, but for example, an appropriate polyfunctional (meth)acrylate is selected as a component to be used in combination with the polyamide resin and/or polyimide resin. Examples include:

The description regarding the photosensitive resin composition of this embodiment will be continued.

(Polyamide resin and/or polyimide resin)
The photosensitive resin composition of this embodiment contains a polyamide resin and/or a polyimide resin. The structure, molecular weight, amount used, etc. of the polyamide resin and/or polyimide resin are not limited as long as E' ₂₂₀ is 0.5 to 3.0 GPa.

From the viewpoint of reducing the amount of shrinkage during curing, the photosensitive resin composition of this embodiment preferably contains a polyimide resin, and more preferably contains a polyimide resin having an imide ring structure.
When the number of moles of imide groups contained in the polyimide resin is IM, and the number of moles of amide groups contained in the polyimide resin is AM, the imidization rate is expressed as {IM/(IM+AM)}×100(%) is preferably 90% or more, more preferably 95% or more, even more preferably 98% or more. In short, it is preferable that the polyimide resin has no or few ring-opened amide structures and many ring-closed imide structures. By using such a polyimide resin, shrinkage due to heating (curing shrinkage) can be further suppressed (because dehydration due to ring-closing reaction does not occur). Thereby, it is possible to further improve the reliability of the electronic device and the flatness of the cured film.
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 polyamide resin and/or polyimide resin contain a fluorine atom. The present inventors have found that polyamide resins and/or polyimide resins containing fluorine atoms tend to have better solubility in organic solvents than those containing no fluorine atoms. Therefore, by using a polyamide resin and/or a polyimide resin containing a fluorine atom, the photosensitive resin composition can easily have a varnish-like property.
The amount (mass ratio) of fluorine atoms in the polyamide resin and/or 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 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 polyamide resin and/or polyimide resin in various ways, for example, the mechanical properties (tensile elongation, etc.) of the cured product can be further improved.

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

Regarding the terminal structure, it is preferable that the polyamide resin and/or polyimide resin do not have a maleimide structure at its terminal.

The polyamide resin preferably contains a structural unit represented by the following general formula (PA-1).

The polyimide resin preferably contains a structural unit represented by the following general formula (PI-1).

In general formulas (PA-1) and (PI-1),
X is a divalent organic group,
Y is a tetravalent organic group.

In general formulas (PA-1) and (PI-1), at least one of X and Y is preferably a fluorine atom-containing group. From the viewpoint of organic solvent solubility, both X and Y in general formulas (PA-1) and (PI-1) are preferably fluorine atom-containing groups.

In general formulas (PA-1) and (PI-1), the divalent organic group of X and/or the tetravalent organic group of Y preferably contains an aromatic ring structure, and preferably contains a benzene ring structure. More preferred. This tends to further improve heat resistance. The benzene ring here may be substituted with a fluorine atom-containing group such as a fluorine atom or a fluorinated alkyl group (preferably a trifluoromethyl group), or may be substituted with another group.
The divalent organic group of X and/or the tetravalent organic group of Y in general formulas (PA-1) and (PI-1) preferably have 2 to 6 benzene rings connected to a single bond or a divalent organic group. It has a structure in which it is bonded through a 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.
In general formulas (PA-1) and (PI-1), the divalent organic group of X has, for example, 6 to 30 carbon atoms.
In general formulas (PA-1) and (PI-1), the number of carbon atoms in the tetravalent organic group of Y is, for example, 6 to 20.
Each of the two imide rings in general formula (PI-1) is preferably a 5-membered ring.

More preferably, the polyamide resin contains a structural unit represented by the following general formula (PA-2).

More preferably, the polyimide resin contains a structural unit represented by the following general formula (PI-2).

In general formulas (PA-2) and (PI-2),
X has the same meaning as X in general formulas (PA-1) and (PI-1),
Y' represents a single bond or an alkylene group.

Specific embodiments of X are the same as those explained in general formulas (PA-1) and (PI-1).
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.

A polyamide resin can typically be obtained by reacting (condensation polymerization) a diamine and an acid dianhydride. A polyimide resin can be obtained by imidizing a polyamide resin (ring-closing reaction). Further, a desired functional group may be introduced at the end of the polymer, if 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 polyamide resin and/or polyimide resin finally obtained, the diamine is incorporated into the polymer as a divalent organic group X in general formula (PA-1) or (PI-1). Further, the acid dianhydride is incorporated into the polymer as a tetravalent organic group Y in the general formula (PA-1) or (PI-1).
In the synthesis of polyamide resin and/or polyimide resin, 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 terminals (both terminals) of the polyamide resin and/or polyimide resin tend to become amino groups. On the other hand, by using an excessive amount of acid dianhydride, the terminals (both terminals) of the polyamide resin and/or polyimide resin tend to become acid anhydride groups. As mentioned above, in this embodiment, the polyamide resin and/or polyimide resin 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 polyamide resin and/or polyimide resin.

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

The weight average molecular weight of the polyamide resin and/or polyimide resin is, for example, 5,000 to 100,000, preferably 7,000 to 75,000, and more preferably 10,000 to 50,000. When the weight average molecular weight of the polyamide resin and/or polyimide resin is relatively large, for example, sufficient heat resistance of the cured film can be obtained. Furthermore, since the weight average molecular weight of the polyamide resin and/or polyimide resin is not too large, it becomes easier to dissolve the polyamide resin and/or polyimide resin 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)
The photosensitive resin composition of this embodiment preferably contains a polyfunctional (meth)acrylate compound. Examples of the polyfunctional (meth)acrylate compound include those having two or more (meth)acryloyl groups in one molecule without particular limitation.

The present inventors have discovered that by using a polyamide resin and/or polyimide resin in combination with a polyfunctional (meth)acrylate compound, a photosensitive resin composition having an E' ₂₂₀ of 0.5 to 3.0 GPa can be produced. It is easy to design, and tends to improve the performance of the cured film.

Although the details are unknown, it is thought that when the polyfunctional (meth)acrylate compound is cured (polymerized), a structure that is intricately "entangled" with the polyamide resin and/or polyimide resin is formed. In particular, the polyfunctional (meth)acrylate compound can be formed by polymerization into a polyimide resin having a cyclic skeleton such as an imide ring, or a cyclic skeleton of a polyamide resin which can have a cyclic skeleton by at least a part of the polyamide structure being ring-closed by heat. It is assumed that a network structure is formed that "envelops" the It is presumed that the formation of such a complexly intertwined structure results in an _E'220 of 0.5 to 3.0 GPa and improved performance of the cured film.

From the viewpoint of realizing the above-mentioned entangled structure and from the viewpoint of obtaining a cured film with high durability and good chemical resistance, the polyfunctional (meth)acrylate compound is preferably trifunctional or more functional. Although there is no particular upper limit to the number of functional groups of the polyfunctional (meth)acrylate compound, the upper limit of 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 having a large number of functional groups ((meth)acryloyl groups) is used, the chemical resistance of the cured film tends to increase. On the other hand, when a polyfunctional (meth)acrylate compound having a small number of functional groups ((meth)acryloyl groups) is used, mechanical properties such as tensile elongation of the cured film tend to be good.

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

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

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

As an example, the polyfunctional (meth)acrylate compound can include a compound represented by the following general formula. 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. A plurality of R's may be the same or different.

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

Ethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate , polyol polyacrylates such as dipentaerythritol hexa(meth)acrylate, 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 DPC A60, 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.

When the photosensitive resin composition contains a polyfunctional (meth)acrylate compound, it may contain only one polyfunctional (meth)acrylate compound, or it may contain two or more polyfunctional (meth)acrylate compounds. In the latter case, it is preferable to use polyfunctional (meth)acrylate compounds having different numbers of functional groups together. It is thought that by using polyfunctional (meth)acrylate compounds with different numbers of functional groups in combination, a more complex "entangled structure" can be created, further improving the properties of the cured film.
Incidentally, among commercially available polyfunctional (meth)acrylate compounds, there are also mixtures of (meth)acrylates with different numbers of functional groups.

When using a polyfunctional (meth)acrylate compound, the amount of the polyfunctional (meth)acrylate compound relative to 100 parts by mass of the polyamide resin and/or polyimide resin is preferably 50 to 200 parts by mass, more preferably 60 to 150 parts by mass. be.
Although the amount of the polyfunctional (meth)acrylate compound 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 polyamide resin and/or polyimide resin and polyfunctional (meth)acrylate is formed by curing. By appropriately adjusting the amount of the polyfunctional (meth)acrylate compound used in the resin and/or polyimide resin, the polyamide resin and/or polyimide resin and the polyfunctional (meth)acrylate compound can be moderately entangled, and also participate in the entanglement. It is thought that the amount of unnecessary components will be reduced. It is thought that the performance will further improve.

(Photosensitizer)
The photosensitive resin composition of this embodiment preferably contains a photosensitizer. The photosensitizer 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 preferably contains a photoradical generator. Photoradical generators are particularly effective in polymerizing polyfunctional (meth)acrylate compounds.

The photoradical generator that can be used is not particularly limited, and known ones can be used as appropriate.
For example, 2,2-diethoxyacetophenone, 2,2-dimethoxy2-phenylacetophenone, 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-( 2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl} -2-methylpropan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl) -Butanone-1,2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone and other alkylphenone compounds; benzophenone, 4 , 4'-bis(dimethylamino)benzophenone, 2-carboxybenzophenone, and other benzophenone compounds; benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and other benzoin compounds; thioxanthone, 2-ethylthioxanthone, - Thioxanthone compounds such as 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-oxa Diazole, 2-trichloromethyl-5-[β-(2'-benzofuryl)vinyl]-1,3,4-oxadiazole, 4-oxadiazole, 2-trichloromethyl-5-furyl-1,3 , 4-oxadiazole and other halomethylated oxadiazole compounds; 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) Biimidazole compounds such as -4,4',5,5'-tetraphenyl-1,2'-biimidazole; 1,2-octanedione, 1-[4-(phenylthio)phenyl]-2-(O -benzoyloxime), 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; p-dimethylaminobenzoic acid, Examples include benzoic acid ester compounds such as p-diethylaminobenzoic acid; acridine compounds such as 9-phenylacridine; and the like. Among these, oxime ester compounds can be particularly preferably used.

When the photosensitive resin composition contains a photosensitizer, it may contain only one type of photosensitizer, or may contain two or more types of photosensitizer.
When using a photosensitizer, the amount used is, for example, 1 to 30 parts by weight, preferably 3 to 20 parts by weight, based on 100 parts by weight of the polyfunctional (meth)acrylate compound.

(Thermal radical initiator)
The photosensitive resin composition of this embodiment preferably contains a thermal radical initiator. By using a thermal radical initiator, it is easy to appropriately adjust the value of CTE2/CTE1, which will be described later, to further improve the reliability of electronic devices, and to further increase the heat resistance of the cured film. This is considered to be because the use of a thermal radical initiator further promotes the polymerization reaction of the polyfunctional (meth)acrylate compound.

The thermal radical initiator preferably includes 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, methyl ethyl ketone peroxide, acetyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, cumene hydroperoxide, dicumyl peroxide, Examples include t-butyl perbenzoate, parachlorobenzoyl peroxide, and cyclohexanone peroxide.

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

(Epoxy resin)
The photosensitive resin composition of this embodiment preferably contains an epoxy resin. Although the details are unknown, it is believed that the epoxy resin reacts (forms a bond) with, for example, a polyamide resin and/or a polyimide resin. Furthermore, the mechanical properties (tensile elongation, etc.) of the cured film tend to be improved, probably due to the flexibility of the ether structure formed by the reaction.

As the epoxy resin, any compound having one or more (preferably two or more) epoxy groups in one molecule can be used as appropriate.
Specific examples of epoxy resins include n-butyl glycidyl ether, 2-ethoxyhexyl glycidyl ether, phenyl glycidyl ether, allyl glycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerol poly Glycidyl ethers such as glycidyl ether, sorbitol polyglycidyl ether, glycidyl ether of bisphenol A (or F), glycidyl esters such as adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, 3,4-epoxycyclohexylmethyl (3, 4-epoxycyclohexane) carboxylate, 3,4-epoxy-6-methylcyclohexylmethyl (3,4-epoxy-6-methylcyclohexane) carboxylate, bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate, Dicyclopentanediene oxide, bis(2,3-epoxycyclopentyl) ether, and alicyclic epoxy resins such as Celoxide 2021P, Celoxide 2081, Celoxide 2083, Celoxide 2085, Celoxide 8000, and Epolead GT401 manufactured by Daicel, 2,2 '-((((1-(4-(2-(4-(oxiran-2-ylmethoxy)phenyl)propan-2-yl)phenyl)ethane-1,1-diyl)bis(4,1-phenylene ))bis(oxy))bis(methylene))bis(oxirane)) (for example, Techmore VG3101L manufactured by Printec Corporation), Epolite 100MF (manufactured by Kyoeisha Chemical Industry Co., Ltd.), Epiol TMP (manufactured by NOF Corporation), etc. Aliphatic polyglycidyl ether, 1,1,3,3,5,5-hexamethyl-1,5-bis(3-(oxiran-2-ylmethoxy)propyl)trisiloxane (for example, DMS-E09 (manufactured by Gelest) )).

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

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

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

As curing catalysts, mention may be made of compounds known as curing catalysts (often also referred to as 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 a curing catalyst is used, the amount thereof is, for example, 1 to 80 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the epoxy resin.

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

Examples of the silane coupling agent 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. A silane coupling agent such as a ureido group-containing silane coupling agent, a sulfide group-containing silane coupling agent, a silane coupling agent having a cyclic anhydride structure, and the like 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 polyamide resin and/or polyimide resin, and therefore a particularly good adhesion improving effect can be obtained.

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

(surfactant)
The photosensitive resin composition of this embodiment preferably contains a surfactant. Thereby, the coatability of the photosensitive resin composition and the flatness of the film can be further improved.
Examples of the surfactant include fluorine surfactants, silicone surfactants, alkyl surfactants, and acrylic surfactants.

The surfactant preferably contains a surfactant containing at least one of a fluorine atom and a silicon atom. This contributes to obtaining a uniform resin film (improving coating properties), improving developability, and improving adhesive strength.
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.

Commercial products that can be preferably used as surfactants include, for example, F-251, F-253, F-281, F-430, F-477, and F-551 of the "Megafac" series manufactured by DIC Corporation. , F-552, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F -565, F-568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, etc. , fluorine-containing oligomeric structure surfactants, fluorine-containing nonionic surfactants such as Ftergent 250 and Ftergent 251 manufactured by Neos Co., Ltd., SILFOAM (registered trademark) series manufactured by Wacker Chemie (for example, SD 100) Examples include silicone surfactants such as TS, SD 670, SD 850, SD 860, 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 a surfactant, it can contain one or more surfactants.
When the photosensitive resin composition of the present embodiment contains a surfactant, 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 the polyamide resin and/or polyimide resin is 100 parts by mass. The amount is 0.005 to 0.5 parts by mass.

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

When the photosensitive resin composition of the present embodiment contains water, the amount thereof is preferably 0.1 to 5 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the total solid content (nonvolatile components) of the photosensitive resin composition. The amount is preferably 0.2 to 3 parts by weight, more preferably 0.5 to 2 parts by weight.
The water content of the photosensitive resin composition can be determined by the Karl Fischer method.

(Properties of solvent/composition)
The photosensitive resin composition of this embodiment preferably contains a solvent. Thereby, a photosensitive resin film can be easily formed on a substrate (particularly a substrate having a step) by a coating method.
The solvent usually includes an organic solvent.
The solvent is not particularly limited as long as it is capable of dissolving or dispersing each of the above-mentioned components and does not substantially chemically react with each component.

Examples of the solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, Propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate and methyl-3-methoxy Examples include propionate. The solvents may be used alone or in combination.

When the photosensitive resin composition of this embodiment contains a solvent, the photosensitive resin composition of this embodiment is usually in the form of a varnish. More specifically, the photosensitive resin composition of this embodiment is preferably a varnish-like composition in which at least a polyamide resin and/or a polyimide resin is dissolved in a solvent.
Since the photosensitive resin composition of this embodiment is varnish-like, it is possible to form a uniform film by coating. Moreover, since the polyamide resin and/or polyimide resin is "dissolved" in the solvent, a homogeneous cured film can be obtained.

When a solvent is used, it is used so that the concentration of the total solid content (nonvolatile components) in the photosensitive resin composition is preferably 10 to 50% by mass, more preferably 20 to 45% by mass. By setting it as this range, each component can 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 polyamide resin and/or polyimide resin and the polyfunctional (meth)acrylate compound in the entire composition is preferably 20 to 50% by mass. By using a certain amount of polyamide resin and/or polyimide resin and polyfunctional (meth)acrylate compound, 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 antioxidants, fillers such as silica, sensitizers, film-forming agents, and the like.

(About various physical properties)
Regarding the photosensitive resin composition of this embodiment, in addition to designing the composition so that _E'220 is 0.5 to 3.0 GPa, further performance improvement can be achieved by satisfying other physical properties. can be achieved.

As one point of view, the reliability of the electronic device can be further improved by appropriate thermal expansion behavior of the cured product of the photosensitive resin composition of the present embodiment.
in particular,
・The glass transition temperature of the cured film obtained by heating the photosensitive resin composition at 170°C for 2 hours is Tg [°C],
・The thermal expansion coefficient of the cured film in the temperature range from Tg-50 [°C] to Tg-20 [°C] is CTE1,
- When the thermal expansion coefficient of the cured film in the temperature range from Tg + 20 [°C] to Tg + 50 [°C] is CTE2, the value of CTE2/CTE1 is preferably 1 to 10, more preferably 1 to 7, and further Preferably it is 1-5.
It is thought that by designing the photosensitive resin composition so that CTE2 is not excessively large compared to CTE1, deterioration/softening of the cured film due to heating in the electronic device manufacturing process can be further suppressed. It is also believed that the reliability of electronic devices will be further improved.
Ideally, the value of CTE2/CTE1 is preferably close to 1, but from the viewpoint of practical composition design, the lower limit is, for example, about 1.1.

Incidentally, the value of CTE1 itself is preferably 2×10 ⁻⁵ to 8×10 ⁻⁵ /°C, more preferably 2×10 ⁻⁵ to 8×10 ⁻⁵ /°C, even more preferably 3×10 ⁻⁵ to 7×10 ⁻⁵ /°C, particularly preferably 4×10 ⁻⁵ to 6×10 ⁻⁵ /°C.
Further, the value of CTE2 itself is preferably 2×10 ⁻⁵ to 100×10 ⁻⁵ /°C, more preferably 2×10 ⁻⁵ to 80×10 ⁻⁵ /°C, even more preferably 5×10 ⁻⁵ to 60×10 ⁻⁵ /°C, particularly preferably 5×10 ⁻⁵ to 50×10 ⁻⁵ /°C.
Further, the glass transition temperature Tg is preferably 170 to 270°C, more preferably 170 to 250°C, even more preferably 200 to 250°C, particularly preferably 210 to 230°C.

In addition to the thermal expansion behavior of the cured product, we aim to further improve the performance by designing the storage modulus of the cured film of the photosensitive resin composition to an appropriate value at 250 to 280°C. I can do it. Specifically, the details are as follows.

In the dynamic viscoelasticity measurement under the above-mentioned [conditions], the storage modulus E' ₂₅₀ at 250°C of the cured film of the photosensitive resin composition of this embodiment is preferably 0.3 GPa or more, more preferably 0. .3 GPa or more and 3.0 GPa or less, more preferably 0.5 GPa or more and 2.0 GPa or less.
In the dynamic viscoelasticity measurement under the above-mentioned [conditions], the storage modulus E' ₂₈₀ at 280°C of the cured film of the photosensitive resin composition of this embodiment is preferably 0.1 GPa or more, more preferably 0 .1 GPa or more and 2.0 GPa or less, more preferably 0.2 GPa or more and 1.0 GPa or less.
By designing a photosensitive resin composition so that E' ₂₅₀ and E' ₂₈₀ are within the above numerical range, for example, peeling of the cured film can be suppressed even in a reflow process that requires high temperatures, and the properties of electronic devices can be improved. It is thought that reliability will be further improved.

<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 film forming step is usually performed by applying a photosensitive resin composition onto the substrate. The film forming step can be performed using a spin coater, a bar coater, a spray device, an inkjet device, or the like.
Before the next exposure step, it is preferable to perform appropriate heating for the purpose of drying the solvent in the applied photosensitive resin composition. The heating at this time is performed, for example, at a temperature of 80 to 150° C. for 1 to 60 minutes.
The thickness of the photosensitive resin film after drying varies appropriately depending on the structure of the electronic device to be finally obtained, but is, for example, about 1 to 100 μm, specifically about 1 to 50 μm.

The amount of exposure in the exposure step is not particularly limited. 100 to 2000 mJ/cm ² is preferable, and 200 to 1000 mJ/cm ² is more preferable.
The light source used for exposure is not particularly limited, and any light source that emits light of a wavelength (for example, g-line or i-line) that reacts with the photosensitizer in the photosensitive resin composition may be used. Typically a high pressure mercury lamp is used.
If necessary, baking may be performed after exposure. The temperature of the post-exposure bake 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. The post-exposure bake time is preferably 1 to 30 minutes, more preferably 1 to 20 minutes, and even more preferably 1 to 15 minutes.
A photomask can be used in the exposure process. Thereby, a desired "pattern" can be formed using the photosensitive resin composition.

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.

The conditions for the thermosetting step are not particularly limited, but may be, for example, at a heating temperature of about 160 to 250° C. for about 30 to 240 minutes.

Hereinafter, a specific example of the method for manufacturing an electronic device will be described with reference to the drawings. A specific example of the electronic device manufacturing method to be described is a method characterized by sealing the semiconductor chip 40 from the side opposite to the side on which the electrode pads 30 are arranged, and is a so-called method. This is a method for manufacturing a fan-out wafer level package (FO-WLP) type electronic device.

First, as shown in FIG. 1(a), a plurality of semiconductor chips 40 obtained by cutting a semiconductor wafer, which has been made passivated in advance by forming a passivation film 50, into pieces are separated at predetermined intervals. A structure is prepared in which the terminal surface of the semiconductor chip 40 (the surface on which the electrode pad 30 is disposed) is attached to the adhesive surface of the adhesive member 200. As a material for forming the passivation film 50, a photosensitive resin composition used for forming the first insulating resin film 60 described later can be used.
In the structure of FIG. 1(a), the plurality of semiconductor chips 40 are embedded inside the encapsulant 10 such that the electrode pads 30 provided on the respective surfaces thereof all face in the same direction. It is preferable that the
A pillar-shaped conductor portion made of metal such as copper may be formed on the electrode pad 30 provided on the semiconductor chip 40. Furthermore, a solder bump may be formed on the end surface of the conductor section opposite to the side on which the electrode pad is arranged.

Next, as shown in FIG. 1(b), the plurality of semiconductor chips 40 attached to the adhesive member 200 are covered and sealed with a cured product of the resin composition for semiconductor sealing. In addition, in this embodiment, the cured product of the resin composition for semiconductor encapsulation refers to a encapsulating material. As such a resin composition for semiconductor encapsulation, a known material can be used, and examples thereof include an epoxy resin composition containing an epoxy resin, an inorganic filler, and a curing agent.

Examples of methods for encapsulating the semiconductor chip 40 using the resin composition for semiconductor encapsulation include transfer molding, compression molding, injection molding, and lamination. Among these, a transfer molding method, a compression molding method, or a lamination method is preferable from the viewpoint of forming the sealing material 10 without leaving any unfilled portions. Therefore, the resin composition for semiconductor encapsulation used in the present manufacturing method is preferably in the form of granules, powder, tablets, or sheets. Further, from the viewpoint of suppressing the occurrence of positional displacement of the semiconductor chip 40 during molding of the sealing material 10, a compression molding method is particularly preferable.

Next, as shown in FIG. 1(c), the adhesive member 200 is peeled off. By doing so, it is possible to obtain a structure in which a plurality of semiconductor chips 40 having electrode pads 30 on the surface are embedded inside the sealing material 10. The adhesive member 200 is preferably peeled from the structure after reducing the adhesion between the adhesive member 200 and the structure. Specifically, the adhesive layer of the adhesive member 200 forming the adhesive part is deteriorated by, for example, applying ultraviolet irradiation or heat treatment to the adhesive part between the adhesive member 200 and the structure, thereby improving the adhesion. One example is a method of reducing this.
The adhesive member 200 is not particularly limited as long as it adheres to the semiconductor chip 40, but for example, a member formed by laminating a back grind tape and an adhesive layer can be mentioned.
The structure shown in FIG. 1C is a structure in which the surface of the semiconductor chip 40 opposite to the side on which the electrode pads 30 are arranged is covered with the sealing material 10. In this manufacturing method, before peeling off the adhesive member 200, the encapsulant 10 is polished and removed by a known method so that the surface of the semiconductor chip 40 opposite to the side on which the electrode pads 30 are arranged is exposed. There may be a step to do so.

Next, as shown in FIG. 2A, a first insulating resin film 60 is formed on the surface of the obtained structure on the side where the electrode pad 30 is embedded. Specifically, the first insulating resin film 60 is formed by applying a varnish-like resin composition to the surface of the above-described structure on which the electrode pad 30 is embedded and drying it. do. The thickness of the first insulating resin film 60 can be, for example, 1 to 300 μm. As a method for applying the resin composition, known methods such as a spin coating method, a slit coating method, and an inkjet method can be employed. Among these, it is preferable to employ a spin coating method.

In this manufacturing method, it is preferable to use the above-mentioned photosensitive resin composition (the composition described in the section <Photosensitive resin composition>) as the resin material constituting the first insulating resin film 60.

In this manufacturing method, before forming the first insulating resin film 60, it is preferable to plasma-treat the surface of the sealing material 10 on the side where the first insulating resin film 60 is to be formed. By doing so, the wettability of the first insulating resin film 60 can be improved. As a result, the adhesion between the sealing material 10 and the first insulating resin film 60 can be made even better.
In plasma processing, for example, argon gas, oxidizing gas, or fluorine gas can be used as the processing gas. Examples of the oxidizing gas include O ₂ gas, O ₃ gas, CO gas, CO ₂ gas, NO gas, and NO ₂ gas. For example, it is preferable to use an oxidizing gas as the processing gas. Further, as the oxidizing gas, it is preferable to use, for example, O ₂ gas. Thereby, specific functional groups can be formed on the surface of the sealing material 10. Therefore, the adhesion and applicability of the first insulating resin film 60 to the sealing material 10 can be further improved, and the reliability of the electronic device can be further improved.

The conditions of the plasma treatment are not particularly limited, but in addition to ashing treatment, a treatment of contacting with plasma derived from an inert gas may be used. Further, the plasma treatment according to the present manufacturing method is preferably a plasma treatment performed without applying a bias voltage to the processing target, or a plasma treatment performed using a non-reactive gas.
Furthermore, in this manufacturing method, chemical treatment may be performed instead of plasma treatment, or both plasma treatment and chemical treatment may be performed. Examples of chemicals that can be used in the chemical treatment include alkaline permanganate aqueous solutions such as potassium permanganate and sodium permanganate.

Next, as shown in FIG. 2B, a first opening 250 is formed in the first insulating resin film 60 to expose a part of the electrode pad 30. As a method for forming the first opening 250, an exposure and development method or a laser processing method can be used. Further, it is preferable to perform a descum treatment on the formed first opening 250 to remove scum (resin residue) generated when forming the first opening 250.

The descum treatment may be performed by plasma irradiation. At this time, as the processing gas, for example, argon gas, O ₂ gas, O ₃ gas, CO gas, CO ₂ gas, NO gas, NO ₂ gas, or fluorine gas can be used.

Next, as shown in FIG. 2C, a conductive film 110 is formed to cover the exposed electrode pad 30 and the first insulating resin film 60. The conductive film 110 is, for example, an electrolytic copper plating film, a solder plating film, a tin plating film, a two-layer plating film in which a gold plating film is laminated on a nickel plating film, or an under bump metal (UBM) formed by electroless plating. It can be any of the following, such as a membrane. Furthermore, the thickness of the conductive film 110 can be, for example, 2 to 10 μm.
Regarding the obtained conductive film 110, from the viewpoint of improving the durability of the electronic device 100 finally obtained, the surface thereof may be subjected to plasma treatment by a method similar to the method described above.

As the plating method, for example, an electrolytic plating method or an electroless plating method can be adopted. When using electroless plating, the conductive film 110 can be formed as follows. An example in which a conductive film 110 made of two layers of nickel and gold is formed will be described below, but the present invention is not limited thereto.
First, a nickel plating film is formed. When performing electroless nickel plating, the structure shown in FIG. 2(b) is immersed in a plating solution. By doing so, the conductive film 110 can be formed on the surfaces of the electrode pad 30 and the first insulating resin film 60. The plating solution may contain nickel lead and, for example, hypophosphite as a reducing agent. Subsequently, electroless gold plating is performed on the nickel plating film. The method of electroless gold plating is not particularly limited, but it can be performed, for example, by displacement gold plating, which is performed by replacing gold ions with underlying metal ions.

In this way, in FO-WLP, the semiconductor chip 40 is embedded with the sealing material 10. The circuit surface of the semiconductor chip 40 is exposed to the outside, and a boundary between the semiconductor chip 40 and the sealing material 10 is formed. A conductive film 110 (rewiring layer) connected to the electrode pads 30 of the semiconductor chip 40 is also provided in the region of the encapsulant 10 in which the semiconductor chip 40 is embedded, and the bumps are connected to the conductive film 110 (rewiring layer) through the conductive film 110 (rewiring layer). It is electrically connected to the electrode pad 30 of the semiconductor chip 40. The pitch of the bumps can be set larger than the pitch of the electrode pads 30 of the semiconductor chip 40.

Next, as shown in FIG. 3A, a second insulating resin film 70 is formed on the surface of the conductive film 110. Thereafter, in this embodiment, as shown in FIG. 3B, a second opening 300 is formed to expose a part of the conductive film 110.
The second insulating resin film 70 and the second opening 300 can be formed using the same method as the first insulating resin film 60 and the first opening 250 described above. The material for forming the second insulating resin film 70 is a photosensitive resin composition used for forming the first insulating resin film 60 (i.e., described in the section <Photosensitive resin composition>). composition) can be used.

Next, as shown in FIG. 3C, the solder bump 80 or the end of the bonding wire is melted and fused onto the conductive film 110 exposed in the second opening 300. In this way, the electronic device 100 according to this embodiment can be obtained.
Thereafter, although not shown, the electronic device 100 is cut along the dicing lines formed on the electronic device 100 so as to include at least one semiconductor chip 40, thereby dividing the electronic device into individual pieces into a plurality of semiconductor packages (electronic devices). can be converted into

In addition, in this manufacturing method, starting from the structure shown in FIG. Devices can also be made. According to this manufacturing method, it is also possible to manufacture an electronic device including, for example, four layers of conductive films (wiring layers) and five layers of insulating resin films. In this case, the method for forming the conductive film (wiring layer) can be the same as the method for forming the conductive film 110. Furthermore, the method for forming the insulating resin film can be the same as the method for forming the first insulating resin film 60.
When manufacturing an electronic device having the multilayer wiring structure described above, solder bumps 80 are placed on the outermost layer or the ends of bonding wires are melted to form a conductive film (wiring layer) using a method similar to that described above. By attaching the substrate, the obtained electronic device can be electrically connected.

This manufacturing method is related to a method of starting from the structure shown in FIG. 1(c) and forming an insulating resin film and a conductive film (wiring layer) only on one surface of the structure. When the structure shown in 1(c) is in a state where the surface of the semiconductor chip 40 opposite to the side on which the electrode pad 30 is arranged is also exposed, an insulating resin film is formed on both surfaces of the structure. You may.

This manufacturing method can also be applied to the process of manufacturing chip-sized semiconductor packages, but from the perspective of improving the productivity of semiconductor packages, it has been applied to the process of manufacturing so-called wafer-level packages, or The present invention may be applied to a process for manufacturing a panel level package based on the premise of using area panels.

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.
Below, examples of reference forms will be added.
1.
A photosensitive resin composition containing a polyamide resin and/or a polyimide resin,
When the cured film obtained by heating the photosensitive resin composition at 170°C for 2 hours was subjected to dynamic viscoelasticity measurement under the following conditions, the storage modulus E' 220 at 220°C was 0.5 to _0.5 . A photosensitive resin composition having a pressure of 3.0 GPa.
[conditions]
Frequency: 1Hz
Temperature: 30-300℃
Heating rate: 5℃/min
Measurement mode: tensile mode
2.
1. The photosensitive resin composition described in
The glass transition temperature of the cured film is Tg [°C],
The thermal expansion coefficient of the cured film in the temperature range from Tg-50 [°C] to Tg-20 [°C] is CTE1, and the thermal expansion coefficient of the cured film in the temperature range from Tg+20 [°C] to Tg+50 [°C] A photosensitive resin composition having a CTE2/CTE1 value of 1 to 10, where CTE2 is CTE2.
3.
1. or 2. The photosensitive resin composition described in
A photosensitive resin composition containing a polyimide resin having an imide ring structure.
4.
1. ~3. The photosensitive resin composition according to any one of
Furthermore, a photosensitive resin composition containing a polyfunctional (meth)acrylate compound.
5.
1. ~4. The photosensitive resin composition according to any one of
Furthermore, a photosensitive resin composition containing a photosensitizer.
6.
5. The photosensitive resin composition described in
The photosensitive agent is a photosensitive resin composition containing a photoradical generator.
7.
1. The photosensitive resin composition according to any one of ~6 to 6,
Furthermore, a photosensitive resin composition containing a thermal radical initiator.
8.
1. The photosensitive resin composition according to any one of ~7 to 7,
Furthermore, a photosensitive resin composition containing an epoxy resin.
9.
1. The photosensitive resin composition according to any one of ~8 to 8,
A photosensitive resin composition in the form of a varnish in which at least the polyamide resin and/or polyimide resin is dissolved in a solvent.
10.
1. ~9. The photosensitive resin composition according to any one of
A photosensitive resin composition used for forming insulating layers in electronic devices.
11.
On the substrate, 1. ~10. A film forming step of forming a photosensitive resin film using the photosensitive resin composition according to any one of
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:
12.
11. A method for manufacturing an electronic device according to
A method for manufacturing an electronic device, including a thermosetting step of heating and curing the exposed photosensitive resin film after the developing step.
13.
1. ~10. An electronic device comprising a cured film of the photosensitive resin composition according to any one of the above.

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, "DMAc" is an abbreviation for dimethylacetamide. Other abbreviations will be explained as appropriate in the text.

<Polymer synthesis>
(Synthesis of polymer (A-1))
In a glass 3L separable flask equipped with a stirring device and stirring blades, 64.1 g (0.20 mol) of TFMB<2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl> 97.7 g (0.22 mol) of 6FDA<4,4'-(hexafluoroisopropylidene)diphthalic dianhydride> and 500 g of DMAc were charged and stirred to dissolve TFMB and 6FDA in DMAc. Further, under a nitrogen stream, stirring was continued at room temperature for 12 hours to carry out a polymerization reaction to obtain a polyamic acid solution.

After adding 16 g of pyridine to the obtained polyamic acid solution, 82 g of acetic anhydride was added dropwise at room temperature. Thereafter, the solution temperature was maintained at 20 to 100° C. and stirring was continued for 24 hours to carry out an imidization reaction to obtain a polyimide solution.

The obtained polyimide solution was poured into 1,000 g of methanol with stirring in a 5 L container to precipitate the polyimide resin. Thereafter, the solid polyimide resin was filtered out using a suction filtration device, and further washed with 1,000 g of methanol. Then, using a vacuum dryer, it was dried at 100°C for 24 hours, and further dried at 200°C for 3 hours. Through the above steps, Polymer (A-1), which is a polyimide powder having an acid anhydride group at the end, was obtained.
Polymer (A-1) had a weight average molecular weight (Mw) of 25,000 as measured by GPC.
Further, the polymer (A-1) was subjected to ¹ H-NMR measurement, and the imidization rate (as defined above) was calculated from the quantitative value of the amide peak relative to the aromatic ring peak of polyimide. The imidization rate was 99% or more.

(Synthesis of polymer (A-2))
Instead of 64.1 g (0.20 mol) of TFMB, 56.4 g (0.176 mol) of TFMB and BAPP-F<2,2,-bis[4-(4-aminophenoxy)phenyl]-1,1,1 , 3,3,3-hexafluoropropane>12.4 g (0.024 mol) was used, but polymer synthesis was carried out in the same manner as in Polymer (A-1). Polymer (A-2), which is a polyimide powder having an acid anhydride group at the end, was obtained.
The weight average molecular weight (Mw) of Polymer (A-2) was 26,000 as measured by GPC. Furthermore, the imidization rate of the polymer (A-2) as determined by NMR measurement was 99% or more.

(Synthesis of polymer (A-3))
Except that 78.2 g (0.176 mol) of 6FDA and 13.7 g (0.044 mol) of ODPA<4,4'-oxydiphthalic dianhydride> were used instead of 97.7 g (0.22 mol) of 6FDA. Polymer synthesis was performed in the same manner as Polymer (A-1). Polymer (A-3), which is a polyimide powder having an acid anhydride group at the end, was obtained.
Polymer (A-3) had a weight average molecular weight (Mw) of 24,000 as measured by GPC. Furthermore, the imidization rate of Polymer (A-3) was 99% or more as determined by NMR measurement.

(Synthesis of polymer (A-4))
Instead of 97.7 g (0.22 mol) of 6FDA, 83.1 g (0.187 mol) of 6FDA and 9.71 g (0.033 Polymer synthesis was carried out in the same manner as Polymer (A-1) except that mol) was used. A polyimide resin (A-4) having an acid anhydride group at the end was obtained.
Polymer (A-4) had a weight average molecular weight (Mw) of 24,000 as measured by GPC. Further, the imidization rate of the polymer (A-4) as determined by NMR measurement was 99% or more.

(Synthesis of polymer (A-5))
Polymer (A A polymer was synthesized in the same manner as in -1). Polymer (A-5), which is a polyimide powder having an acid anhydride group at the end, was obtained.
Polymer (A-5) had a weight average molecular weight (Mw) of 25,000 as measured by GPC. Furthermore, the imidization rate of the polymer (A-5) as determined by NMR measurement was 99% or more.

<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.

<Polyamide resin and/or polyimide resin>
(A-1) Polymer synthesized above (A-2) Polymer synthesized above (A-3) Polymer synthesized above (A-4) Polymer synthesized above (A-5) Polymer synthesized above

The structures of each of the above polymers are shown below.

<Polyfunctional (meth)acrylate compound>
(B-1) Viscoat #802 (manufactured by Osaka Organic Industry Co., Ltd., a mixture of compounds having 5 to 10 acryloyl groups per molecule)
(B-2) NK ester A-9550 (manufactured by Shin Nakamura Chemical Co., Ltd., a mixture of compounds having 5 to 6 acryloyl groups per molecule)
(B-3) Viscoat #300 (manufactured by Osaka Organic Industry Co., Ltd., a mixture of compounds having 3 to 4 acryloyl groups per molecule)
(B-4) Viscoat #230 (manufactured by Osaka Organic Industry Co., Ltd., a compound having two acryloyl groups per molecule)

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

<Photosensitizer>
(C-1) Irugacure OXE01 (manufactured by BASF, oxime ester type photoradical generator)
(C-2) ADEKA Arkles NCI-730 (manufactured by ADEKA Co., Ltd., oxime ester type photoradical generator)

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

<Epoxy resin>
(E-1) TECHMORE VG3101L (manufactured by Printec Co., Ltd.)
(E-2) Celoxide 2021P (manufactured by Daicel Corporation)

<Curing catalyst>
(F-1) Tetraphenylphosphonium 4,4'-sulfonyl diphenolate The method for synthesizing the curing catalyst (F-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. As a result of the above, the desired product in the form of white crystals was obtained.

<Silane coupling agent>
(G-1) KBM-503 (manufactured by Shin-Etsu Chemical Co., Ltd., (meth)acryloyl group-containing silane coupling agent)
(G-2) X-12-967C (manufactured by Shin-Etsu Chemical Co., Ltd., silane coupling agent having a cyclic anhydride structure)

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

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

<Dynamic viscoelasticity measurement of cured film (measurement of E' ₂₂₀ , etc.)>
(Preparation of test piece)
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 coated film.
The obtained coating film was exposed to light of 1000 mJ/cm ² using a high-pressure mercury lamp. Thereafter, a post-exposure bake was performed at 120° C. for 3 minutes, followed by immersion in cyclopentanone for 30 seconds. Furthermore, after that, a hardening treatment was performed by heating at 170° C. for 2 hours in a nitrogen atmosphere. A cured film of the photosensitive resin composition was obtained in the above manner.
The obtained cured product was cut with a dicing saw into a width of 5 mm for each silicon wafer. The cured film was peeled off from the wafer by immersing the cut piece in a 2% by mass hydrofluoric acid aqueous solution.
The peeled cured film was dried at 60° C. for 10 hours to obtain a test piece (30 mm x 5 mm x 10 μm thick).

The obtained test piece was heated from 30°C to 300°C in a nitrogen atmosphere using a dynamic viscoelasticity measurement device (manufactured by TA, Q800) at a frequency of 1Hz, tensile mode, and a heating rate of 5°C/min. Then, the storage modulus versus temperature was measured. From the obtained storage elastic modulus (E') curve, the storage elastic modulus [MPa] at 220°C, 250°C and 280°C was read.

<Measurement of thermal expansion coefficient and glass transition temperature (Tg)>
Using a thermomechanical analyzer (TMA/SS6000, manufactured by Seiko Instruments), a test piece obtained in the same manner as in the dynamic viscoelasticity measurement of the cured film above was heated to 300°C at a heating rate of 10°C/min. heated to. The relationship between temperature and displacement at this time was graphed.
The glass transition temperature (Tg) of the cured product was determined from the position of the inflection point of the obtained graph. In addition, in the obtained graph, the coefficient of linear expansion in the region from Tg-50 [°C] to Tg-20 [°C] is defined as CTE1, and the coefficient of linear expansion in the region from Tg+20 [°C] to Tg+50 [°C] is defined as CTE2. were calculated respectively. Then, the value of CTE2/CTE1 was calculated.

<Reliability evaluation (temperature cycle test)>
(Creation of board for reliability evaluation)
The photosensitive resin composition was spin-coated onto a 12-inch silicon wafer so that the film thickness after drying was 5 μm, and then heated at 120° C. for 3 minutes to obtain a coated film.
The obtained coating film was exposed to light of 1000 mJ/cm ² using a high-pressure mercury lamp. Thereafter, a post-exposure bake was performed at 120° C. for 3 minutes, followed by immersion in cyclopentanone for 30 seconds. Furthermore, after that, a hardening treatment was performed by heating at 170° C. for 2 hours in a nitrogen atmosphere. Through the above steps, a cured film of the first layer of the photosensitive resin composition was obtained.
On the obtained cured film, Ti and Cu were deposited by sputtering to a thickness of 500 Å and 3000 Å, respectively. Thereafter, Cu wiring was formed with a height of 5 μm by electrolytic plating via a resist. After peeling off the resist layer, the sputtered Cu and sputtered Ti were etched to create Cu wiring with line/space=2 μm/2 μm.
Subsequently, the photosensitive resin composition was treated in the same manner as the first layer except that the film thickness was changed to 10 μm to obtain a substrate for reliability evaluation.

(Reliability test)
The reliability evaluation board obtained as above was set in a temperature cycle test device (TCT device), and the temperature was raised from -60°C to 200°C and then lowered to -60°C for one cycle. 1000 cycles were performed.
Subsequently, a cross section of the Cu wiring portion was taken out by FIB (focused ion beam) processing and observed using a SEM. In each Example and Comparative Example, the interface between the wiring and the resin film was observed at a total of 10 locations.
◎ (very good) if no peeling was observed at all 10 locations, ○ (good) if peeling was observed at 1 or 2 of the 10 locations, and ○ (good) if peeling was observed at 3 or more locations. What was observed was evaluated as × (poor).

<Evaluation of insulation reliability>
(Preparation of samples for insulation reliability)
A Cu wiring board was fabricated on a silicon wafer with an oxide film, in which comb-shaped Cu wiring with a width of 5 μm/pitch of 5 μm and a height of 5 μm was formed.
The photosensitive resin composition was applied onto the Cu wiring board by spin coating so that the film thickness after drying (the thickness of the area without wiring) was 10 μm, and dried at 120°C for 3 minutes to make it photosensitive. A resin film was formed.
The obtained photosensitive resin film was exposed to light at 300 mJ/cm ² using a high-pressure mercury lamp. Thereafter, it was immersed in cyclopentanone for 30 seconds. Thereafter, heat treatment was performed at 170° C. for 2 hours in a nitrogen atmosphere to obtain a cured film. This was used as a sample for insulation reliability evaluation.

(Insulation reliability evaluation)
A simulated electronic device for evaluation was prepared by soldering the ends of the Cu wiring (Cu electrodes) of the substrate prepared above (preparation of samples for insulation reliability) and electrode wiring. This was placed in an environment of 130° C./85% RH while applying a bias of 3.5 V using a B-HAST device.
The insulation resistance value between the Cu wirings of the Cu wiring board was automatically measured at 6 minute intervals, and a case where the insulation resistance value became 1.0×10 4 Ω or less was defined as dielectric breakdown. Then, the time from the start of the test to dielectric breakdown was measured. In the table below, cases where the time was 210 hours or more were indicated as ◎ (very good), cases between 50 and 210 hours were indicated as ○ (good), and cases where the time was less than 50 hours were indicated as × (bad).

<Evaluation of shear strength at 250°C>
A residual pattern of 100 μm×100 μm was created on an 8-inch silicon wafer on which plated copper had been formed, using the same method as in <Evaluation of patterning properties> above. Thereafter, a curing treatment was performed at 170° C. for 2 hours in a nitrogen atmosphere to obtain a sample for shear strength measurement.
The obtained sample was tested for shear strength (thermal shear strength, unit: MPa) at 250°C under the conditions of a shear speed of 200 nm/sec and a shear height of 1 μm using a die shear device (manufactured by Nordson, Dage-4000). was measured. A large value means that the cured film is difficult to peel off even when exposed to high temperatures. In other words, from the viewpoint of reliability of the electronic device, it is preferable that this value is larger.

<Evaluation of cure shrinkage rate>
The photosensitive resin composition was spin-coated onto an 8-inch silicon wafer so that the film thickness after drying was 10 μm. Subsequently, heating was performed 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, it was immersed in cyclopentanone for 30 seconds, and then dried using a spin dryer to obtain a developed film of the photosensitive resin composition. The film thickness of this developed film was measured and was defined as film thickness A.
Thereafter, the developed film was cured by heat treatment at 170° C. for 2 hours in a nitrogen atmosphere. Through the above steps, a cured film of the photosensitive resin composition was obtained. The thickness of this cured film was measured and defined as film thickness B.
The cure shrinkage rate was calculated by substituting the film thickness A and the film thickness B into the following formula. The cure shrinkage rate is preferably small in order to maintain flatness after coating on the wiring.
Curing shrinkage rate [%] = {(film thickness A - film thickness B) / film thickness A} x 100

<Evaluation of flatness during coating (step filling flatness)>
A Cu wiring board was prepared in which Cu wiring having a width of 5 μm/pitch of 5 μm and a height of 5 μm was formed on a silicon wafer with an oxide film. On this Cu wiring board, a photosensitive resin composition was applied by spin coating so that the film thickness after drying was 10 μm, and dried at 120° C. for 3 minutes to form 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, it was immersed in cyclopentanone for 30 seconds. Furthermore, after that, heat treatment was performed at 170° C. for 2 hours in a nitrogen atmosphere to form a cured film on the substrate.
The obtained substrate with the cured film was broken, the cross section thereof was polished, and the unevenness of the surface of the photosensitive resin film was evaluated by cross-sectional SEM observation. Those with surface irregularities of 1 μm or less were evaluated as ○ (good), those with surface irregularities of 1 to 3 μm were evaluated as Δ (usable level), and those with surface irregularities exceeding 3 μm were evaluated as × (bad).

<Evaluation of tensile elongation rate>
First, a test piece was prepared in the same manner as in (Preparation of test piece) in <Dynamic viscoelasticity measurement of cured film (measurement of E' ₂₂₀ , etc.)> above.
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.

<Evaluation of patternability>
The photosensitive resin composition was applied onto an 8-inch silicon wafer 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 (photosensitive resin film A).
This photosensitive resin film was passed through a mask manufactured by Toppan Printing Co., Ltd. (Test Chart No. 1: a left pattern and a cutout pattern with a width of 0.5 to 50 μm are drawn), and then passed through an i-line stepper (manufactured by Nikon Corporation, NSR-4425i). ), the i-line was irradiated while changing the exposure amount.
Thereafter, the film was developed for 30 seconds using cyclopentanone as a developer, and dried by spinning at 2500 rpm for 10 seconds to obtain a developed film (negative pattern).
Those with a via hole of 7 μm Φ were evaluated as ◎ (very good), those with a via hole of 10 μm Φ were evaluated as ○ (good), and those with a via hole of 10 μm in diameter were evaluated as × (bad).

Table 1 summarizes the combination of raw materials and measurement/evaluation results for each composition.

As shown in Table 1, the results of temperature cycle tests of the photosensitive resin compositions of Examples 1 to 14 (containing polyamide resin and/or polyimide resin, and having E' ₂₂₀ of 0.5 to 3.0 GPa) The evaluation results of insulation reliability and shear strength at 250°C were all good. These evaluation results showed that it is possible to manufacture highly reliable electronic devices by curing the photosensitive resin composition of this embodiment by heating at about 170° C. to form a cured film.
Furthermore, the curing shrinkage rates of the cured products of the photosensitive resin compositions of Examples 1 to 14 were small, and the evaluation of step embedding flatness was good. Furthermore, the cured products of the photosensitive resin compositions of Examples 1 to 14 were moderately elongated. In addition, the photosensitive resin compositions of Examples 1 to 14 had sufficient patterning performance during the manufacture of electronic devices.

Looking at the example in more detail, the following is understood.
- Comparing Example 11 with other Examples, the glass transition temperature of the cured product tends to increase and the CTE2/CTE1 tends to decrease due to the use of a thermal radical generator. The reliability tends to be improved by using a thermal radical generator. This is probably because the use of the thermal radical generator further promotes the polymerization of the polyfunctional (meth)acrylate compound.
- Comparing Examples 12 and 13 with other examples, there is a tendency for the tensile elongation rate to improve by using an epoxy resin or its curing catalyst. It is thought that a cured film that is more stretchable and less likely to break is probably formed by bond formation (crosslinking) between the polyamide resin and/or polyimide resin and the epoxy resin.
- From the comparison between Example 14 and other Examples, it is considered that the presence of water probably causes the adhesion aid to work better and improves the adhesion.

On the other hand, the evaluation results of the photosensitive resin composition of Comparative Example 1 in which E' ₂₂₀ was less than 0.50 GPa were inferior to the evaluation results of the photosensitive resin compositions of Examples 1 to 14.

10 Sealing material 30 Electrode pad 40 Semiconductor chip 50 Passivation film 60 Insulating resin film (first insulating resin film)
70 Insulating resin film (second insulating resin film)
80 Solder bump 100 Electronic device 110 Conductive film 200 Adhesive member 250 Opening (first opening)
300 opening (second opening)

Claims (12)

A photosensitive resin composition comprising a polyamide resin and/or polyimide resin, and a polyfunctional (meth)acrylate compound that is a different component from the polyamide resin and/or polyimide resin and is not a surfactant ,
When the cured film obtained by heating the photosensitive resin composition at 170°C for 2 hours was subjected to dynamic viscoelasticity measurement under the following conditions, the storage modulus E' ₂₂₀ at 220°C was 0.5 to 0.5. A photosensitive resin composition having a pressure of 3.0 GPa. However, this excludes cases where the polyamide resin and/or polyimide resin are alkali-soluble.
[conditions]
Frequency: 1Hz
Temperature: 30-300℃
Heating rate: 5℃/min Measurement mode: Tensile mode The photosensitive resin composition according to claim 1,
The glass transition temperature of the cured film is Tg [°C],
The thermal expansion coefficient of the cured film in the temperature range from Tg-50 [°C] to Tg-20 [°C] is CTE1, and the thermal expansion coefficient of the cured film in the temperature range from Tg+20 [°C] to Tg+50 [°C] A photosensitive resin composition having a CTE2/CTE1 value of 1 to 10, where CTE2 is CTE2. The photosensitive resin composition according to claim 1 or 2,
A photosensitive resin composition containing a polyimide resin having an imide ring structure. The photosensitive resin composition according to any one of claims 1 to 3 ,
Furthermore, a photosensitive resin composition containing a photosensitizer. The photosensitive resin composition according to claim 4 ,
The photosensitive agent is a photosensitive resin composition containing a photoradical generator. The photosensitive resin composition according to any one of claims 1 to 5 ,
Furthermore, a photosensitive resin composition containing a thermal radical initiator. The photosensitive resin composition according to any one of claims 1 to 6 ,
Furthermore, a photosensitive resin composition containing an epoxy resin. The photosensitive resin composition according to any one of claims 1 to 7 ,
A photosensitive resin composition in the form of a varnish in which at least the polyamide resin and/or polyimide resin is dissolved in a solvent. The photosensitive resin composition according to any one of claims 1 to 8 ,
A photosensitive resin composition used for forming insulating layers in electronic devices. 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 9 ;
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 10 , 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 9 .

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