WO2023286728A1 - Resin composition for semiconductor sealing, and semiconductor device - Google Patents

Abstract

This resin composition for semiconductor sealing includes an epoxy resin (A), a curing agent (B) containing a phenol resin (B1) and an active ester resin (B2), and a curing accelerator (C). The active ester resin (B2) has a structure represented by general formula (1). The curing accelerator (C) contains one or more substances selected from the group consisting of tetraphenylphosphonium-4,4'-sulfonyldiphenolate, tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate, and 4-hydroxy-2-(triphenylphosphonium)phenolate.

Description

Resin composition for semiconductor encapsulation and semiconductor device

The present invention relates to a resin composition for semiconductor encapsulation and a semiconductor device.

Thermosetting resin compositions (sealing resin compositions) are known as materials for sealing semiconductor packages and the like.

Patent Documents 1 and 2 disclose a sealing resin composition containing an epoxy resin, an active ester compound as a curing agent, and an inorganic filler having a predetermined average particle size.

Patent Document 3 discloses a sealing resin composition containing an epoxy resin containing a polyfunctional epoxy resin and a difunctional epoxy resin, and an active ester compound as a curing agent.

WO2020/065872 WO2020/065873 WO2020/066856

However, in the conventional encapsulating resin compositions described in Patent Documents 1 to 3, the shrinkage rate during molding is high and the yield of the product is low. had room for improvement.

The present inventors have found that the above problems can be solved by using a phenolic resin and an active ester resin together as a curing agent, and by using a resin composition for semiconductor encapsulation containing a predetermined curing accelerator, and have completed the present invention. let me
That is, the present invention can be shown below.

（一般式（１）において、Ａは、脂肪族環状炭化水素基を介して連結された置換または非置換のアリーレン基であり、
　Ａｒ’は、置換または非置換のアリール基であり、
　ｋは、繰り返し単位の平均値であり、０．２５～３．５の範囲であり、
　一般式（１）においてＢは、一般式（Ｂ）で表される構造であり、

（一般式（Ｂ）中、Ａｒは、置換または非置換のアリーレン基であり、Ｙは、単結合、置換または非置換の炭素原子数１～６の直鎖のアルキレン基、または置換または非置換の炭素原子数３～６の環式のアルキレン基、置換または非置換の２価の芳香族炭化水素基、エーテル結合、カルボニル基、カルボニルオキシ基、スルフィド基、あるいはスルホン基である。ｎは０～４の整数である。）
　硬化促進剤（Ｃ）は、テトラフェニルホスホニウム－４，４’－スルフォニルジフェノラート、テトラフェニルホスホニウムビス（ナフタレン－２，３－ジオキシ）フェニルシリケート、４－ヒドロキシ－２－（トリフェニルホスホニウム）フェノラートからなる群より選択される１種または２種以上を含む、半導体封止用樹脂組成物。
［２］　［１］に記載の半導体封止用樹脂組成物であって、
　前記一般式（Ｂ）で表される構造は、一般式（Ｂ－１）～（Ｂ－６）から選択される少なくとも１つである、半導体封止用樹脂組成物。

（一般式（Ｂ－１）～（Ｂ－６）中、Ｒ^１は、それぞれ独立に水素原子、炭素原子数１～４のアルキル基、炭素原子数１～４のアルコキシ基、フェニル基、またはアラルキル基であり、Ｒ^２はそれぞれ独立に炭素原子数１～４のアルキル基、炭素原子数１～４のアルコキシ基、またはフェニル基であり、Ｘは炭素原子数２～６の直鎖のアルキレン基、エーテル結合、カルボニル基、カルボニルオキシ基、スルフィド基、スルホン基のいずれかであり、ｎは０～４の整数であり、ｐは１～４の整数である。）
［３］　［１］または［２］に記載の半導体封止用樹脂組成物であって、
　前記一般式（１）において、Ａが、一般式（Ａ）で表される構造を有する、半導体封止用樹脂組成物。

（一般式（Ａ）中、Ｒ^３はそれぞれ独立に水素原子、炭素原子数１～４のアルキル基、炭素原子数１～４のアルコキシ基、フェニル基、アラルキル基の何れかであり、ｌは０または１であり、ｍは１以上の整数である）
［４］　［１］～［３］のいずれかに記載の半導体封止用樹脂組成物であって、
　フェノール樹脂（Ｂ１）の含有量と活性エステル樹脂（Ｂ２）の含有量の比率が、２５：７５～７５：２５である、半導体封止用樹脂組成物。
［５］　［１］～［４］のいずれかに記載の半導体封止用樹脂組成物であって、
　さらにカップリング剤（Ｄ）を含む、半導体封止用樹脂組成物。
［６］　［５］に記載の半導体封止用樹脂組成であって、
　カップリング剤（Ｄ）が２級アミノシランカップリング剤である、半導体封止用樹脂組成物。
［７］　［１］～［６］のいずれかに記載の半導体封止用樹脂組成であって
　エポキシ樹脂（Ａ）およびフェノール樹脂（Ｂ１）の少なくとも一方が、ビフェニルアラルキル構造を有する、半導体封止用樹脂組成物。
［８］　［１］～［７］のいずれかに記載の半導体封止用樹脂組成であって
　フェノール樹脂（Ｂ１）が、ビフェニルアラルキル構造を有する、半導体封止用樹脂組成物。
［９］　［１］～［８］のいずれかに記載の半導体封止用樹脂組成であって、
　エポキシ樹脂（Ａ）が、ビフェニルアラルキル型樹脂およびジシクロペンタジエン型樹脂から選択される少なくとも１種を含む、半導体封止用樹脂組成物。
［１０］　［１］～［９］のいずれかに記載の半導体封止用樹脂組成物であって、
　さらにシリコーンオイル（Ｅ）を含む、半導体封止用樹脂組成物。
［１１］　［１］～［１０］のいずれかに記載の半導体封止用樹脂組成物であって、
　さらに無機充填剤（Ｆ）を含む、半導体封止用樹脂組成物。
［１２］　［１１］に記載の半導体封止用樹脂組成物であって、
　無機充填剤（Ｆ）が、シリカ、アルミナ、タルク、酸化チタン、窒化珪素、窒化アルミニウムから選択される少なくとも１種である、半導体封止用樹脂組成物。
［１３］　［１］～［１２］のいずれかに記載の半導体封止用樹脂組成物であって、
　当該半導体封止用樹脂組成物のゲルタイムが５０秒以上８０秒以下である、半導体封止用樹脂組成物。
［１４］　半導体素子と、
　［１］～［１３］のいずれかに記載の半導体封止用樹脂組成物の硬化物からなる、前記半導体素子を封止する封止材と、
を備える、半導体装置。 [1] (A) an epoxy resin;
(B) a curing agent;
(C) a curing accelerator, and a resin composition for semiconductor encapsulation,
The curing agent (B) contains a phenol resin (B1) and an active ester resin (B2),
The active ester resin (B2) has a structure represented by the general formula (1),

(In general formula (1), A is a substituted or unsubstituted arylene group linked via an aliphatic cyclic hydrocarbon group,
Ar' is a substituted or unsubstituted aryl group;
k is the average value of the repeating units and ranges from 0.25 to 3.5;
In general formula (1), B is a structure represented by general formula (B),

(In the general formula (B), Ar is a substituted or unsubstituted arylene group, Y is a single bond, a substituted or unsubstituted linear alkylene group having 1 to 6 carbon atoms, or a substituted or unsubstituted is a cyclic alkylene group having 3 to 6 carbon atoms, a substituted or unsubstituted divalent aromatic hydrocarbon group, an ether bond, a carbonyl group, a carbonyloxy group, a sulfide group, or a sulfone group, n is 0 is an integer between ~4.)
Curing accelerator (C) is tetraphenylphosphonium-4,4'-sulfonyldiphenolate, tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate, 4-hydroxy-2-(triphenylphosphonium)phenolate. A semiconductor encapsulating resin composition comprising one or more selected from the group consisting of:
[2] The resin composition for semiconductor encapsulation according to [1],
The resin composition for semiconductor encapsulation, wherein the structure represented by the general formula (B) is at least one selected from the general formulas (B-1) to (B-6).

(In general formulas (B-1) to (B-6), R ¹ is each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group, each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and X is a linear alkylene group having 2 to 6 carbon atoms; group, ether bond, carbonyl group, carbonyloxy group, sulfide group, or sulfone group, n is an integer of 0 to 4, and p is an integer of 1 to 4.)
[3] The resin composition for semiconductor encapsulation according to [1] or [2],
A resin composition for semiconductor encapsulation, wherein in the general formula (1), A has a structure represented by the general formula (A).

(In general formula (A), each R ³ is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group, and l is 0 or 1, and m is an integer of 1 or more)
[4] The resin composition for semiconductor encapsulation according to any one of [1] to [3],
A resin composition for semiconductor encapsulation, wherein the ratio of the content of the phenol resin (B1) to the content of the active ester resin (B2) is 25:75 to 75:25.
[5] The resin composition for semiconductor encapsulation according to any one of [1] to [4],
A resin composition for semiconductor encapsulation, further comprising a coupling agent (D).
[6] The resin composition for semiconductor encapsulation according to [5],
A resin composition for semiconductor encapsulation, wherein the coupling agent (D) is a secondary aminosilane coupling agent.
[7] The resin composition for semiconductor encapsulation according to any one of [1] to [6], wherein at least one of the epoxy resin (A) and the phenol resin (B1) has a biphenylaralkyl structure. resin composition for
[8] The resin composition for semiconductor encapsulation according to any one of [1] to [7], wherein the phenolic resin (B1) has a biphenylaralkyl structure.
[9] The resin composition for semiconductor encapsulation according to any one of [1] to [8],
A resin composition for semiconductor encapsulation, wherein the epoxy resin (A) contains at least one selected from biphenylaralkyl-type resins and dicyclopentadiene-type resins.
[10] The resin composition for semiconductor encapsulation according to any one of [1] to [9],
A resin composition for semiconductor encapsulation, further comprising a silicone oil (E).
[11] The resin composition for semiconductor encapsulation according to any one of [1] to [10],
A resin composition for semiconductor encapsulation, further comprising an inorganic filler (F).
[12] The resin composition for semiconductor encapsulation according to [11],
A resin composition for semiconductor encapsulation, wherein the inorganic filler (F) is at least one selected from silica, alumina, talc, titanium oxide, silicon nitride and aluminum nitride.
[13] The resin composition for semiconductor encapsulation according to any one of [1] to [12],
A resin composition for semiconductor encapsulation, wherein the gel time of the resin composition for semiconductor encapsulation is 50 seconds or more and 80 seconds or less.
[14] a semiconductor element;
A sealing material for sealing the semiconductor element, which is composed of a cured product of the resin composition for semiconductor sealing according to any one of [1] to [13];
A semiconductor device comprising:

The resin composition for semiconductor encapsulation of the present invention has a low shrinkage rate during molding and excellent product yield, and the cured product obtained from the composition has excellent mechanical strength and dielectric properties. In other words, the resin composition for semiconductor encapsulation of the present invention has an excellent balance of these properties.

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

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

The resin composition for semiconductor encapsulation of the present embodiment contains an epoxy resin (A), a curing agent (B), and a curing accelerator (C).
Hereinafter, each component contained in the resin composition for semiconductor encapsulation (hereinafter also referred to as the resin composition for encapsulation) of the present embodiment will be described.

[Epoxy resin (A)]
Epoxy resin (A) is a compound having two or more epoxy groups in one molecule, and may be any of monomer, oligomer and polymer.

The epoxy resin (A) specifically includes crystalline epoxy resins such as biphenyl-type epoxy resin, bisphenol-type epoxy resin, and stilbene-type epoxy resin; multifunctional epoxy resins such as trisphenylmethane epoxy resins and alkyl-modified triphenolmethane epoxy resins; phenol aralkyl epoxy resins such as phenylene skeleton-containing phenol aralkyl epoxy resins and biphenylene skeleton-containing phenol aralkyl epoxy resins; dihydroxynaphthalene type epoxy resins, naphthol-type epoxy resins such as epoxy resins obtained by glycidyl-etherifying a dimer of dihydroxynaphthalene; triazine nucleus-containing epoxy resins such as triglycidyl isocyanurate and monoallyl diglycidyl isocyanurate; dicyclopentadiene-modified phenol It is one or more selected from the group consisting of bridged cyclic hydrocarbon compound-modified phenol type epoxy resins such as type epoxy resins.

From the viewpoint of the effect of the present invention, the epoxy resin (A) is preferably trisphenylmethane type epoxy resin, biphenylaralkyl type polyfunctional epoxy resin, orthocresol type bifunctional epoxy resin, biphenyl type bifunctional epoxy resin, bisphenol type It is one or more selected from the group consisting of bifunctional epoxy resins and dicyclopentadiene type bifunctional epoxy resins. More preferably, the epoxy resin (A) is a biphenylaralkyl-type polyfunctional epoxy resin or a dicyclopentadiene-type bifunctional epoxy resin.

The content of the epoxy resin (A) in the encapsulating resin composition is, with respect to the entire encapsulating resin composition, from the viewpoint of obtaining suitable fluidity during molding and improving filling properties and moldability. The content is preferably 2% by mass or more, more preferably 3% by mass or more, and still more preferably 4% by mass or more.
In addition, from the viewpoint of improving the reliability of the device obtained using the encapsulating resin composition, the content of the epoxy resin (A) in the encapsulating resin composition is set to is preferably 40% by mass or less, more preferably 30% by mass or less, still more preferably 20% by mass or less, and particularly preferably 10% by mass or less.

[Curing agent (B)]
In this embodiment, the curing agent (B) contains a phenol resin (B1) and an active ester resin (B2).

(Phenolic resin (B1))
As the phenolic resin (B1), those commonly used in encapsulating resin compositions can be used as long as the effects of the present invention are achieved.

Phenolic resin (B1) includes, for example, phenols such as phenol novolak resin and cresol novolac resin, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, α-naphthol, β-naphthol, dihydroxynaphthalene. Novolac resins obtained by condensation or co-condensation of phenols such as phenols and formaldehyde or ketones in the presence of an acidic catalyst, phenols having a biphenylene skeleton synthesized from the above phenols and dimethoxyparaxylene or bis(methoxymethyl)biphenyl Examples include aralkyl resins, phenol aralkyl resins such as phenol aralkyl resins having a phenylene skeleton, and phenol resins having a trisphenylmethane skeleton. These may be used alone or in combination of two or more.

In the present embodiment, the phenol resin (B1) preferably has a biphenyl aralkyl structure, specifically a phenol aralkyl resin having a biphenylene skeleton, from the viewpoint of the effects of the present invention. A phenolic resin having a biphenylaralkyl structure has low moisture absorption, low elasticity, and excellent reliability.
In this embodiment, one or both of the epoxy resin (A) and the phenol resin (B1) preferably have a biphenylaralkyl structure.

(Active ester resin (B2))
A resin having a structure represented by the following general formula (1) can be used as the active ester resin (B2).

In formula (1), "B" is the structure represented by formula (B).

In formula (B), Ar is a substituted or unsubstituted arylene group. Substituents of the substituted arylene group include alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, phenyl groups and aralkyl groups.
Y is a single bond, a substituted or unsubstituted linear alkylene group having 1 to 6 carbon atoms, or a substituted or unsubstituted cyclic alkylene group having 3 to 6 carbon atoms, or a substituted or unsubstituted divalent is an aromatic hydrocarbon group, an ether bond, a carbonyl group, a carbonyloxy group, a sulfide group, or a sulfone group. Substituents for the aforementioned groups include alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, phenyl groups, aralkyl groups and the like.
Preferred examples of Y include a single bond, a methylene group, —CH(CH ₃ ) ₂ —, an ether bond, an optionally substituted cycloalkylene group, an optionally substituted 9,9-fluorenylene group, and the like.
n is an integer of 0-4, preferably 0 or 1;
Specifically, B is a structure represented by the following general formula (B1) or the following general formula (B2).

In general formula (B1) and general formula (B2) above, Ar and Y have the same meanings as in general formula (B).

A is a substituted or unsubstituted arylene group linked via an aliphatic cyclic hydrocarbon group;
Ar' is a substituted or unsubstituted aryl group;
k is the average value of repeating units and ranges from 0.25 to 3.5.

The resin composition for semiconductor encapsulation of the present embodiment contains a specific active ester resin (B2) together with the phenol resin (B1), so that the shrinkage rate during molding is low and the yield of the product is excellent. A cured product (sealing material) having excellent dielectric loss tangent can be obtained.

The active ester resin (B2) used in the resin composition for semiconductor encapsulation of the present embodiment has an active ester group represented by formula (B). In the curing reaction between the epoxy resin (A) and the active ester resin (B2), the active ester group of the active ester resin (B2) reacts with the epoxy group of the epoxy resin to generate secondary hydroxyl groups. This secondary hydroxyl group is blocked by an ester residue of the active ester resin (B2). Therefore, the dielectric loss tangent of the cured product is reduced.

In one embodiment, the structure represented by formula (B) above is preferably at least one selected from the following formulas (B-1) to (B-6).

In formulas (B-1) to (B-6),
each R ¹ is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group;
Each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and X is a linear alkylene group having 2 to 6 carbon atoms, ether a bond, a carbonyl group, a carbonyloxy group, a sulfide group, or a sulfone group,
n is an integer of 0-4 and p is an integer of 1-4.

Since the structures represented by the above formulas (B-1) to (B-6) are all highly oriented structures, when using an active ester resin (B2) containing this, the resulting resin composition The cured product has a low dielectric constant and a low dielectric loss tangent, and has excellent adhesion to metals, so that it can be suitably used as a semiconductor encapsulating material.
Among them, from the viewpoint of low dielectric constant and low dielectric loss tangent, an active ester resin (B2) having a structure represented by formula (B-2), formula (B-3) or (B-5) is preferable, and furthermore, the formula A structure in which n in (B-2) is 0, a structure in which X in formula (B-3) is an ether bond, or two carbonyloxy groups in formula (B-5) are at the 4,4′-positions An active ester resin (B2) having a structure is more preferred. Moreover, all R ¹ in each formula are preferably hydrogen atoms.

“Ar′” in formula (1) is an aryl group, such as a phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 3,5-xylyl group, o-biphenyl group, m-biphenyl group, p-biphenyl group, 2-benzylphenyl group, 4-benzylphenyl group, 4-(α-cumyl)phenyl group, 1-naphthyl group, 2-naphthyl group and the like. Among them, a 1-naphthyl group or a 2-naphthyl group is preferable because a cured product having particularly low dielectric constant and dielectric loss tangent can be obtained.

In the present embodiment, "A" in the active ester resin (B2) represented by formula (1) is a substituted or unsubstituted arylene group linked via an aliphatic cyclic hydrocarbon group. The arylene group includes, for example, a structure obtained by polyaddition reaction of an unsaturated aliphatic cyclic hydrocarbon compound containing two double bonds in one molecule and a phenolic compound.

The unsaturated aliphatic cyclic hydrocarbon compounds containing two double bonds in one molecule are, for example, dicyclopentadiene, cyclopentadiene oligomers, tetrahydroindene, 4-vinylcyclohexene, 5-vinyl-2-norbornene. , limonene, etc., and these may be used alone or in combination of two or more. Among these, dicyclopentadiene is preferable because a cured product having excellent heat resistance can be obtained. Since dicyclopentadiene is contained in petroleum distillates, industrial dicyclopentadiene may contain cyclopentadiene polymers and other aliphatic or aromatic diene compounds as impurities. However, considering performance such as heat resistance, curability and moldability, it is desirable to use dicyclopentadiene products with a purity of 90% by mass or more.

On the other hand, the phenolic compounds include, for example, phenol, cresol, xylenol, ethylphenol, isopropylphenol, butylphenol, octylphenol, nonylphenol, vinylphenol, isopropenylphenol, allylphenol, phenylphenol, benzylphenol, chlorophenol, bromophenol, 1-naphthol, 2-naphthol, 1,4-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene and the like, each alone You may use and you may use two or more types together. Among these, phenol is preferable because it becomes an active ester resin (B2) having high curability and excellent dielectric properties in a cured product.

In a preferred embodiment, "A" in the active ester resin (B2) represented by formula (1) has a structure represented by formula (A). A resin composition containing an active ester resin (B2) in which "A" in formula (1) has the following structure has a low dielectric constant and a low dielectric loss tangent in its cured product, and is excellent in adhesion to an insert.

In formula (A),
each R ³ is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group;
l is 0 or 1, and m is an integer of 1 or more.

Among the active ester curing agents represented by formula (1), more preferable ones include resins represented by the following formulas (1-1), (1-2) and (1-3), Especially preferred are resins represented by the following formula (1-3).

In formula (1-1), R ¹ and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group. , Z is a phenyl group, a naphthyl group, or a phenyl group or a naphthyl group having 1 to 3 alkyl groups having 1 to 4 carbon atoms on the aromatic nucleus, l is 0 or 1, k is a repeating unit is the average of 0.25 to 3.5.

In formula (1-2), R ¹ and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group. , Z is a phenyl group, a naphthyl group, or a phenyl group or a naphthyl group having 1 to 3 alkyl groups having 1 to 4 carbon atoms on the aromatic nucleus, l is 0 or 1, k is a repeating unit is the average of 0.25 to 3.5.

In formula (1-3), R ¹ and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group. , Z is a phenyl group, a naphthyl group, or a phenyl group or a naphthyl group having 1 to 3 alkyl groups having 1 to 4 carbon atoms on the aromatic nucleus, l is 0 or 1, k is a repeating unit is the average of 0.25 to 3.5.

The active ester resin (B2) used in the present invention comprises a phenolic compound (a) having a structure in which a plurality of aryl groups having a phenolic hydroxyl group are connected via an aliphatic cyclic hydrocarbon group, and an aromatic nucleus-containing dicarboxylic acid. Alternatively, it can be produced by a known method of reacting its halide (b) with an aromatic monohydroxy compound (c).

The reaction ratio of the phenolic compound (a), the aromatic nucleus-containing dicarboxylic acid or its halide (b), and the aromatic monohydroxy compound (c) can be appropriately adjusted according to the desired molecular design. , Among them, since an active ester resin (B2) with higher curability is obtained, the phenolic compound Ratio of 0.25 to 0.90 moles of phenolic hydroxyl groups possessed by (a) and 0.10 to 0.75 moles of hydroxyl groups possessed by the aromatic monohydroxy compound (c) It is preferable to use each raw material in, the phenolic hydroxyl group of the phenolic compound (a) is in the range of 0.50 to 0.75 mol, and the hydroxyl group of the aromatic monohydroxy compound (c) is It is more preferable to use each raw material in a ratio within the range of 0.25 to 0.50 mol.

In addition, the functional group equivalent of the active ester resin (B2) is excellent in curability and has a low dielectric constant and dielectric loss tangent when the total number of functional groups of the resin is the arylcarbonyloxy group and phenolic hydroxyl group in the resin structure. Since a cured product can be obtained, it is preferably in the range of 200 g/eq to 230 g/eq, more preferably in the range of 210 g/eq to 220 g/eq.

The curing agent (B) of this embodiment contains a combination of a phenol resin (B1) and an active ester resin (B2).
As a result, the resin composition for semiconductor encapsulation of the present embodiment has a low shrinkage rate during molding and is excellent in product yield, and the cured product obtained from the composition is excellent in mechanical strength and low dielectric loss tangent.

In the present embodiment, the equivalent ratio of the curing agent (B) to the epoxy resin (A) (curing agent (B)/epoxy resin (A)) is 0.50 to 1.00 from the viewpoint of the effect of the present invention. , preferably 0.52 to 0.95, more preferably 0.55 to 0.90, and particularly preferably 0.60 to 0.80.

In the present embodiment, the equivalent ratio of the active ester resin (B2) to the epoxy resin (A) (active ester resin (B2)/epoxy resin (A)) is 0.10 to 0.60, preferably 0.12. to 0.50, more preferably 0.15 to 0.47, and particularly preferably 0.17 to 0.45.
As a result, the resin composition for semiconductor encapsulation of the present embodiment has excellent curability, so that the shrinkage rate at the time of molding is lower and the yield of the product is more excellent. Better low dielectric loss tangent.
When the equivalent ratio (B2/A) exceeds the upper limit, the hydroxyl group generated when the epoxy group is ring-opened is easily capped with the active ester, resulting in a decrease in the dielectric loss tangent. However, as in the present embodiment, in the curing agent (B) in which the phenol curing agent (B1) and the active ester resin (B2) are used in combination, if the upper limit of the equivalent ratio (B2/A) is exceeded, phenol Since the phenolic hydroxyl group of the curing agent (B1) and the active ester of the active ester resin (B2) act and affect the curing of the epoxy resin (A), the curability (spiral flow, gel time, etc.) varies and heat resistance The properties (Tg, etc.) and mechanical properties (flexural strength, flexural modulus, etc.) are lowered, and moreover, it becomes difficult to control uniform dielectric properties (homogeneity of dielectric properties in the cured body).

In the present embodiment, the equivalent ratio of the phenol resin (B1) to the epoxy resin (A) (phenol resin (B1)/epoxy resin (A)) is 0.10 to 0.70 from the viewpoint of the effects of the present invention. , preferably 0.15 to 0.65, more preferably 0.18 to 0.60, and particularly preferably 0.20 to 0.55.

From the viewpoint of the effect of the present invention, the curing agent (B) has a ratio of the content (parts by weight) of the phenol resin (B1) and the content (parts by weight) of the active ester resin (B2) to 25:75 to 75:25, preferably 30:70 to 70:30.

In the resin composition of the present embodiment, the blending amount of the curing agent (B) containing the phenolic resin (B1) and the active ester resin (B2) and the epoxy resin (A) is excellent in curability, dielectric constant and dielectric loss tangent Since a cured product with a low value can be obtained, it is preferable that the ratio of the epoxy group in the epoxy resin is 0.8 to 1.2 equivalents with respect to the total 1 equivalent of the active groups in the curing agent (B). . Here, the active groups in the curing agent (B) refer to arylcarbonyloxy groups and phenolic hydroxyl groups in the resin structure.

In the composition of the present embodiment, the curing agent (B) is preferably 0.2% by mass or more and 15% by mass or less, more preferably 0.5% by mass or more and 10% by mass, relative to the entire encapsulating resin composition. Hereafter, it is more preferably used in an amount of 1.0% by mass or more and 7% by mass or less.
By including the curing agent (B) in the above range, the obtained cured product can have more excellent dielectric properties and is further excellent in low dielectric loss tangent.

[Curing accelerator (C)]
Curing accelerator (C) is tetraphenylphosphonium-4,4'-sulfonyldiphenolate, tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate, 4-hydroxy-2-(triphenylphosphonium)phenolate. Contains one or more selected from the group consisting of Two types can be included in this embodiment.

From the viewpoint of improving the curing properties of the encapsulating resin composition, the content of the curing accelerator in the encapsulating resin composition is preferably 0.01% by mass or more with respect to the entire encapsulating resin composition. , more preferably 0.05% by mass or more, and still more preferably 0.1% by mass or more.
Moreover, from the viewpoint of obtaining preferable fluidity during molding of the encapsulating resin composition, the content of the curing accelerator in the encapsulating resin composition is preferably 2.5% with respect to the entire encapsulating resin composition. It is 0% by mass or less, more preferably 1.0% by mass or less, and still more preferably 0.5% by mass or less.

[Coupling agent (D)]
The encapsulating resin composition of the present embodiment can contain a coupling agent (D).
Examples of the coupling agent (D) include aminosilanes such as epoxysilane, mercaptosilane, and phenylaminosilane. From the viewpoint of improving the adhesion between the sealing material and the metal member, the coupling agent (D) is preferably epoxysilane or aminosilane, more preferably secondary aminosilane. From a similar point of view, the coupling agent (D) is preferably one or more selected from the group consisting of phenylaminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane. be.

The content of the coupling agent (D) in the encapsulating resin composition is preferably 0 with respect to the entire encapsulating resin composition from the viewpoint of obtaining preferable fluidity during molding of the encapsulating resin composition. 0.01% by mass or more, more preferably 0.05% by mass or more.
Further, from the viewpoint of suppressing increase in resin viscosity, the content of the coupling agent (D) in the sealing resin composition is preferably 2.0% by mass or less with respect to the entire sealing resin composition. , more preferably 1.0% by mass or less, and still more preferably 0.5% by mass or less.

[Silicone oil (E)]
The encapsulating resin composition of the present embodiment can contain silicone oil (E) as a stress reducing agent. As a result, it is possible to suppress warping of a molded body obtained by encapsulating an electronic element or the like with the encapsulating resin composition.

The silicone oil (E) preferably contains organically modified silicone oils such as epoxy-modified silicone oil, carboxyl-modified silicone oil, alkyl-modified silicone oil, and polyether-modified silicone oil. Among these, from the viewpoint of finely dispersing the silicone oil (E) in the resin component and contributing to the suppression of warping, it is particularly preferable to contain a polyether-modified silicone oil.

The content of the silicone oil (E) is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, relative to the entire encapsulating resin composition. Moreover, the content of the silicone oil (E) is preferably 1% by mass or less, more preferably 0.5% by mass or less, relative to the entire encapsulating resin composition. By controlling the content of the silicone oil (E) within such a range, it is possible to contribute to the suppression of warpage of a molded article obtained by encapsulating an electronic element or the like with the encapsulating resin composition.

In this embodiment, other low-stress agents other than the silicone oil (E) can be included, and specific examples include silicones such as silicone rubbers, silicone elastomers and silicone resins; acrylonitrile-butadiene rubbers and the like.

[Inorganic filler (F)]
The encapsulating resin composition of the present embodiment can contain an inorganic filler (F).
As the inorganic filler (F), those generally used in resin compositions for encapsulating semiconductors can be used. Moreover, the inorganic filler (F) may be surface-treated.

Specific examples of the inorganic filler (F) include silica such as fused silica, crystalline silica, and amorphous silicon dioxide; alumina; talc; titanium oxide; silicon nitride; and aluminum nitride. These inorganic fillers may be used alone or in combination of two or more.

The inorganic filler (F) preferably contains silica from the viewpoint of excellent versatility. The shape of silica includes spherical silica, crushed silica, and the like.

The average diameter (D ₅₀ ) of the inorganic filler (F) is preferably 5 μm or more, more preferably 10 μm or more, and preferably 80 μm or less, from the viewpoint of improving moldability and adhesion. It is more preferably 50 µm or less, and still more preferably 40 µm or less.
Here, the particle size distribution of the inorganic filler (F) is obtained by measuring the particle size distribution of particles on a volume basis using a commercially available laser diffraction particle size distribution analyzer (eg, SALD-7000 manufactured by Shimadzu Corporation). can be obtained by

In addition, the maximum particle size of the inorganic filler (F) is preferably 10 μm or more, more preferably 20 μm or more, and preferably 100 μm or less, from the viewpoint of improving moldability and adhesion. It is preferably 80 μm or less.

In addition, the specific surface area of the inorganic filler (F) is preferably 1 m ² /g or more, more preferably 3 m ² /g or more, and preferably 20 m 2 /g or more, from the viewpoint of improving moldability and adhesion. ² /g or less, more preferably 10 m ² /g or less.

The content of the inorganic filler (F) in the encapsulating resin composition improves the low hygroscopicity and low thermal expansion of the encapsulating material formed using the encapsulating resin composition, and the obtained semiconductor device From the viewpoint of more effectively improving the moisture resistance reliability and reflow resistance of the entire sealing resin composition, it is preferably 50% by mass or more, more preferably 60% by mass or more, and still more preferably 65% by mass. % by mass or more.
In addition, from the viewpoint of more effectively improving the fluidity and filling properties during molding of the encapsulating resin composition, the content of the inorganic filler (F) in the encapsulating resin composition is For example, it may be 97% by mass or less, preferably 95% by mass or less, and more preferably 90% by mass or less with respect to the entire composition.

[Other ingredients]
The encapsulating resin composition of the present embodiment may contain components other than the components described above. One or more of the agents can be appropriately blended. Further, the encapsulating resin composition includes, for example, 2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide and 3-amino-5-mercapto-1,2,4-triazole. It may further include one or more.

Release agents include, for example, natural waxes such as carnauba wax; synthetic waxes such as montan acid ester wax and polyethylene oxide wax; higher fatty acids such as zinc stearate and metal salts thereof; paraffin; and carboxylic acid amides such as erucamide. 1 type or 2 or more types selected from the group consisting can be included.
From the viewpoint of improving the releasability of the cured product of the encapsulating resin composition, the content of the release agent in the encapsulating resin composition is preferably 0.00% with respect to the entire encapsulating resin composition. 01% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, and preferably 2.0% by mass or less, more preferably 1.0% by mass 0.5% by mass or less, more preferably 0.5% by mass or less.

Specific examples of ion scavengers include hydrotalcite.
The content of the ion scavenger in the encapsulating resin composition is preferably 0.01% by mass or more with respect to the entire encapsulating resin composition, from the viewpoint of improving the reliability of the encapsulating material. It is more preferably 0.05% by mass or more, more preferably 1.0% by mass or less, and more preferably 0.5% by mass or less.

Specific examples of flame retardants include aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, and phosphazenes.
The content of the flame retardant in the encapsulating resin composition is preferably 1% by mass or more, more preferably 1% by mass or more, based on the entire encapsulating resin composition, from the viewpoint of improving the flame retardancy of the encapsulating material. is 5% by mass or more, preferably 20% by mass or less, and more preferably 10% by mass or less.

Specific examples of colorants include carbon black and red iron oxide.
The content of the coloring agent in the encapsulating resin composition is preferably 0.1% by mass or more with respect to the entire encapsulating resin composition, from the viewpoint of making the color tone of the encapsulating material preferable, It is more preferably 0.2% by mass or more, more preferably 2% by mass or less, and more preferably 1% by mass or less.

Specific examples of antioxidants include hindered phenol compounds, hindered amine compounds, and thioether compounds.

<Resin composition for encapsulation>
The encapsulating resin composition of the present embodiment is solid at room temperature (25° C.), and its shape can be selected according to the molding method of the encapsulating resin composition. , particulate such as granule; and sheet.

Further, with regard to the method for producing the encapsulating resin composition, for example, the respective components described above are mixed by known means, further melt-kneaded with a kneader such as a roll, kneader or extruder, cooled and then pulverized. method. Further, after pulverization, molding may be performed to obtain a particulate or sheet-like encapsulating resin composition. For example, a particulate encapsulating resin composition may be obtained by compression molding into a tablet. Alternatively, a sheet-like encapsulating resin composition may be obtained by, for example, a vacuum extruder. Further, the degree of dispersion, fluidity, etc. of the resulting encapsulating resin composition may be appropriately adjusted.
In addition, when the melting point of the active ester resin (B2) is high, it is preferable that the phenolic resin (B1) and the active ester resin (B2) are melt-mixed in advance and mixed uniformly.

Since the encapsulating resin composition obtained in the present embodiment contains the phenol resin (B1) and the active ester resin (B2) as the curing agent (B), the shrinkage rate is low and the product yield is excellent. A cured product having excellent dielectric properties can be obtained.
The encapsulating resin composition of the present embodiment can be used for transfer molding, injection molding, or compression molding.
Moreover, by using the encapsulating resin composition obtained in the present embodiment, a semiconductor device having excellent product reliability can be obtained.

Next, physical properties of the encapsulating resin composition or its cured product will be described.
The gel time of the encapsulating resin composition of the present embodiment is preferably 50 seconds or more and 80 seconds or less, more preferably 55 seconds or more and 70 seconds or less.
By setting the gel time of the encapsulating resin composition to the above lower limit or more, a package having excellent filling properties can be obtained. On the other hand, by setting the gel time of the encapsulating resin composition to the above upper limit or less, moldability is improved.

The cured product obtained from the encapsulating resin composition of the present embodiment has high flexural strength, and the increase in flexural modulus is smaller than that of conventional cured products, so sealing with excellent mechanical strength and product reliability materials can be provided.
The cured product obtained by curing the encapsulating resin composition of the present embodiment at 175°C for 120 seconds has a bending elastic modulus at room temperature (25°C) of 15,000 MPa or more, preferably 16,000 MPa or more. , more preferably 17,000 MPa or more. Although the upper limit is not particularly limited, it can be 30,000 MPa or less.

The cured product obtained by curing the encapsulating resin composition of the present embodiment at 175°C for 120 seconds has a bending strength at room temperature (25°C) of 60 MPa or more, preferably 80 MPa or more, more preferably 100 MPa. That's it. Although the upper limit is not particularly limited, it can be 200 MPa or less.

In the present embodiment, the upper limit of the molding shrinkage of the encapsulating resin composition is preferably 0.14% or less, more preferably 0.13% or less, and 0.12% or less. is particularly preferred. By keeping the upper limit of the mold shrinkage ratio low, it is possible to suppress the warpage of the molded body. On the other hand, the lower limit of the molding shrinkage of the encapsulating resin composition is preferably −0.5% or more, more preferably −0.3% or more. By setting the shrinkage rate of the molding shrinkage rate within the above range, the molded body can be more easily removed from the mold. For the measurement of the molding shrinkage, for example, using a sealing resin composition, a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.) is used at a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and curing. It can be performed according to JIS K 6911 for a test piece prepared under the condition of 120 seconds.

The dielectric constant of the cured product of the present embodiment at a frequency of 5 GHz can be 4.0 or less, preferably 3.8 or less, more preferably 3.6 or less. This makes it possible to apply the cured product to a low dielectric constant material.

The cured product of the present embodiment has a dielectric loss tangent (tan δ) of 0.007 or less, preferably 0.006 or less, more preferably 0.005 or less when measured at a frequency of 5 GHz. Thereby, the dielectric properties of the cured product can be further improved.

In the present embodiment, the physical properties of the encapsulating resin composition and the cured product are determined by appropriately selecting the type and amount of each component contained in the encapsulating resin composition, the preparation method of the encapsulating resin composition, and the like. can be controlled by selecting

<Semiconductor device>
The semiconductor device according to the present embodiment has a semiconductor element encapsulated with a cured product of the encapsulating resin composition according to the present embodiment described above. Specific examples of semiconductor devices include integrated circuits, large-scale integrated circuits, transistors, thyristors, diodes, solid-state imaging devices, and the like. The semiconductor element is preferably a so-called element that does not involve the input and output of light, excluding optical semiconductor elements such as light-receiving elements and light-emitting elements (light-emitting diodes, etc.).

The base material of a semiconductor device is, for example, a wiring board such as an interposer, or a lead frame. Also, the semiconductor element is electrically connected to the substrate by wire bonding, flip-chip bonding, or the like.

Examples of semiconductor devices obtained by encapsulating a semiconductor element by encapsulation molding using an encapsulating resin composition include MAP (Mold Array Package), QFP (Quad Flat Package), SOP (Small Outline Package), CSP (Chip Size Package), QFN (Quad Flat Non-leaded Package), SON (Small Outline Non-leaded Package), BGA (Ball Grid Array), LF-BGA (Lead Flame BGA), FCBGA (Flip Chip BGA), Types include MAPBGA (Molded Array Process BGA), eWLB (Embedded Wafer-Level BGA), Fan-In type eWLB, and Fan-Out type eWLB.
A more specific description will be given below with reference to the drawings.

1 and 2 are cross-sectional views showing the configuration of a semiconductor device. In this embodiment, the configuration of the semiconductor device is not limited to that shown in FIGS. 1 and 2. FIG.
First, the semiconductor device 100 shown in FIG. 1 includes a semiconductor element 20 mounted on a substrate 30 and a sealing material 50 sealing the semiconductor element 20 .
The encapsulating material 50 is composed of a cured product obtained by curing the encapsulating resin composition of the present embodiment described above.

Also, FIG. 1 illustrates a case where the board 30 is a circuit board. In this case, as shown in FIG. 1, for example, a plurality of solder balls 60 are formed on the other surface of the substrate 30 opposite to the surface on which the semiconductor element 20 is mounted. Semiconductor element 20 is mounted on substrate 30 and electrically connected to substrate 30 via wires 40 . On the other hand, the semiconductor element 20 may be flip-chip mounted on the substrate 30 . Here, the wire 40 includes, but is not limited to, Ag wire, Ni wire, Cu wire, Au wire, and Al wire. Preferably, the wire 40 is Ag, Ni or Cu, or one or more of these. composed of an alloy containing

Sealing material 50 seals semiconductor element 20 so as to cover, for example, the other surface of semiconductor element 20 opposite to the surface facing substrate 30 . In the example shown in FIG. 1, a sealing material 50 is formed so as to cover the other surface and the side surface of the semiconductor element 20 .
In the present embodiment, the encapsulating material 50 is composed of a cured product of the encapsulating resin composition described above. Therefore, in the semiconductor device 100, the adhesion between the sealing material 50 and the wire 40 is excellent, so that the semiconductor device 100 is highly reliable.
The encapsulating material 50 can be formed, for example, by encapsulating the encapsulating resin composition using a known method such as transfer molding or compression molding.

FIG. 2 is a cross-sectional view showing the configuration of the semiconductor device 100 according to this embodiment, and shows an example different from FIG. The semiconductor device 100 shown in FIG. 2 uses a lead frame as the substrate 30 . In this case, semiconductor element 20 is mounted, for example, on die pad 32 of substrate 30 and electrically connected to outer leads 34 via wires 40 . The encapsulant 50 is composed of a cured product of the encapsulating resin composition of the present embodiment in the same manner as in the example shown in FIG.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than those described above can also be adopted.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these.

<Examples 1 to 12, Comparative Examples 1 to 3 (manufacture of encapsulating resin composition)>
Each component described in Tables 1 and 2 was mixed in the described amount ratio to obtain a mixture. Mixing was performed at room temperature using a Henschel mixer.
After that, the mixture was roll kneaded at 70 to 100° C. to obtain a kneaded product. The resulting kneaded product was cooled and then pulverized to obtain a sealing resin composition. Each component described in Tables 1 and 2 is as follows.

(Inorganic filler)
・ Inorganic filler 1: silica (manufactured by Micron, product name: TS-6026, average diameter 9 μm)
・ Inorganic filler 2: Fine silica powder (manufactured by Admatechs, product name: SC-2500-SQ, average diameter 0.6 μm)
・ Inorganic filler 3: Fine silica powder (manufactured by Admatechs, product name: SC-5500-SQ, average diameter 1.6 μm)

(Flame retardants)
・ Flame retardant 1: aluminum hydroxide (manufactured by Nippon Light Metal Co., Ltd., Dp 5 μm)

(coupling agent)
- Silane coupling agent 1: N-phenylaminopropyltrimethoxysilane (manufactured by Dow Corning Toray Co., Ltd., CF-4083)
・ Silane coupling agent 2: 3-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM803P)
- Silane coupling agent 3: 3-glycidoxypropylmethyldimethoxysilane (manufactured by Dow Corning Toray Co., Ltd., AZ-6137)

(Epoxy resin)
・ Epoxy resin 1: biphenyl aralkyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., NC-3000L, epoxy equivalent 273 g / eq)
Epoxy resin 2: Dicyclopentadiene skeleton-containing polyfunctional solid epoxy resin (manufactured by DIC, Epiclon HP-7200L, epoxy equivalent 246 g / eq)

(curing agent)
Phenolic resin: biphenylene skeleton-containing phenol aralkyl type resin (manufactured by Meiwa Kasei Co., Ltd., MEH-7851SS, hydroxyl equivalent 200 g / eq)
Active ester resin 1: Active ester resin prepared by the following preparation method (Preparation method of active ester resin 1)
279.1 g of biphenyl-4,4′-dicarboxylic acid dichloride (moles of acid chloride group: 2.0 mol) and 1338 g of toluene were placed in a flask equipped with a thermometer, dropping funnel, condenser, fractionating tube, and stirrer. was charged, and the inside of the system was replaced with nitrogen under reduced pressure to dissolve. Next, 96.5 g (0.67 mol) of α-naphthol and 219.5 g of dicyclopentadiene phenolic resin (number of moles of phenolic hydroxyl groups: 1.33 mol) were charged, and the system was decompressed and replaced with nitrogen to dissolve. rice field. Thereafter, while purging with nitrogen gas, the inside of the system was controlled at 60° C. or less, and 400 g of a 20% sodium hydroxide aqueous solution was added dropwise over 3 hours. Stirring was then continued under these conditions for 1.0 hour. After completion of the reaction, the mixture was allowed to stand still for liquid separation, and the aqueous layer was removed. Further, water was added to the toluene phase in which the reactants were dissolved, and the mixture was stirred and mixed for about 15 minutes, and the mixture was allowed to stand still for liquid separation to remove the aqueous layer. This operation was repeated until the pH of the aqueous layer reached 7. Thereafter, water was removed by decanter dehydration to obtain an active ester resin 1 in a toluene solution state with a non-volatile content of 65%. When the structure of the obtained active ester resin 1 was confirmed, it had a structure in which R ¹ and R ³ were hydrogen atoms, Z was a naphthyl group, and 1 was 0 in the above formula (1-1). The average value k of the repeating units of active ester resin 1 was in the range of 0.5 to 1.0 as calculated from the reaction equivalence ratio. Moreover, the active group equivalent was 247 g/eq.

Active ester resin 2: Active ester resin prepared by the following preparation method (Preparation method of active ester resin 2)
A flask equipped with a thermometer, dropping funnel, condenser, fractionating tube and stirrer was charged with 203.0 g of 1,3-benzenedicarboxylic acid dichloride (moles of acid chloride group: 2.0 mol) and 1338 g of toluene. It was charged, and the inside of the system was replaced with nitrogen under reduced pressure to dissolve. Next, 96.5 g (0.67 mol) of α-naphthol and 219.5 g of dicyclopentadiene phenolic resin (number of moles of phenolic hydroxyl groups: 1.33 mol) were charged, and the system was decompressed and replaced with nitrogen to dissolve. rice field. Thereafter, while purging with nitrogen gas, the inside of the system was controlled at 60° C. or less, and 400 g of a 20% sodium hydroxide aqueous solution was added dropwise over 3 hours. Stirring was then continued under these conditions for 1.0 hour. After completion of the reaction, the mixture was allowed to stand still for liquid separation, and the aqueous layer was removed. Further, water was added to the toluene phase in which the reactants were dissolved, and the mixture was stirred and mixed for about 15 minutes, and the mixture was allowed to stand still for liquid separation to remove the aqueous layer. This operation was repeated until the pH of the aqueous layer reached 7. After that, water was removed by decanter dehydration to obtain an active ester resin 2 in a toluene solution state with a non-volatile content of 65%. When the structure of the obtained active ester resin was confirmed, it had a structure in which R ¹ and R ³ were hydrogen atoms, Z was a naphthyl group, and 1 was 0 in the above formula (1-3). The average value k of the repeating units of the active ester resin 2 was in the range of 0.5 to 1.0 as calculated from the reaction equivalence ratio. The obtained active ester resin 2 specifically had a structure represented by the following chemical formula. Moreover, the active group equivalent was 209 g/eq.

(Curing accelerator)
Curing accelerator 1: tetraphenylphosphonium 4,4'-sulfonyl diphenolate Curing accelerator 2: tetraphenylphosphonium bis (naphthalene-2,3-dioxy) phenyl silicate Curing accelerator 3: 4-hydroxy-2 - (triphenylphosphonium) phenolate

(Ion scavenger)
・ Ion scavenger 1: magnesium aluminum hydroxide carbonate hydrate (manufactured by Kyowa Chemical Industry Co., Ltd., DHT-4H)

(Wax (release agent))
・Wax 1: Oxidized polyethylene wax (Licowax PED191, manufactured by Clariant Japan)
・Wax 2: Carnauba wax (TOWAX-132, manufactured by Toagosei Co., Ltd.)

(coloring agent)
・ Carbon black: ERS-2001 (manufactured by Tokai Carbon Co., Ltd.)

(Low stress agent)
- Low stress agent 1: Carboxyl group-terminated butadiene-acrylonitrile copolymer (manufactured by Ube Industries, Ltd., CTBN1008SP)
・ Low stress agent 2: Epoxy/polyether modified silicone oil (FZ-3730, manufactured by Dow Corning Toray Co., Ltd.)

<Evaluation>
Evaluation samples were prepared by the following method using the resin composition obtained in each example or the composition, and the adhesion and reliability of the obtained samples were evaluated by the following methods.
[Spiral flow (SF)]
A spiral flow test was conducted using the encapsulating resin compositions of Examples and Comparative Examples.
In the test, using a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.), a mold for spiral flow measurement according to EMMI-1-66 was placed at a mold temperature of 175 ° C. and an injection pressure of 6 A sealing resin composition was injected under conditions of 9 MPa and a curing time of 120 seconds, and the flow length was measured. A higher value indicates better fluidity.

[Gel Time (GT)]
After each of the encapsulating resin compositions of Examples and Comparative Examples was melted on a hot plate heated to 175° C., the time (unit: seconds) until curing was measured while kneading with a spatula.

(glass transition temperature, coefficient of linear expansion (α ₁ and α ₂ ),)
It was measured by the following procedure.
(1) Using a transfer molding machine, the encapsulating resin composition is injection molded under the conditions of a mold temperature of 175°C, an injection pressure of 10.0 MPa, and a curing time of 120 seconds to obtain a molded product of 15 mm × 4 mm × 3 mm. rice field.
(2) The resulting molded article was heated in an oven at 175° C. for 4 hours to fully cure. Then, a test piece (cured product) for measurement was obtained.
(3) Using a thermomechanical analyzer (TMA100, manufactured by Seiko Electronics Industry Co., Ltd.), measurement was performed under the conditions of a measurement temperature range of 0° C. to 320° C. and a heating rate of 5° C./min. From the measurement results, the glass transition temperature Tg (°C), the linear expansion coefficient (α ₁ ) at 40 to 80°C, and the linear expansion coefficient (α ₂ ) at 190 to 230°C were calculated. The unit of α ₁ and α ₂ is ppm/°C, and the unit of glass transition temperature is °C.

[Evaluation of mechanical strength (flexural strength and flexural modulus)]
Using a low-pressure transfer molding machine ("KTS-30" manufactured by Kotaki Seiki Co., Ltd.), the sealing resin composition is placed in a mold under the conditions of a mold temperature of 175 ° C., an injection pressure of 10.0 MPa, and a curing time of 120 seconds. Injection molded. As a result, a molded article having a width of 10 mm, a thickness of 4 mm and a length of 80 mm was obtained. The resulting molded article was then post-cured at 175° C. for 4 hours. This produced a test piece for evaluation of mechanical strength. Then, the flexural strength (MPa) and flexural modulus (MPa) of the test piece at 260° C. or normal temperature (25° C.) were measured according to JIS K 6911.

(Boiling water absorption rate)
For each example and comparative example, the boiling water absorption of the cured product of the obtained encapsulating resin composition was measured as follows. First, using a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.), a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, a curing time of 120 seconds, a diameter of 50 mm, a disk shape test of 3 mm in thickness A piece was molded. Next, after post-curing the obtained test piece at 175° C. for 4 hours, the mass of the test piece before boiling and after boiling in pure water for 24 hours were measured. Based on this measurement result, the change in mass before and after the boiling treatment was calculated, and the boiling water absorption of the test piece was obtained as a percentage. The unit in Table 1 is % by mass.

(Molding shrinkage rate)
For each example and comparative example, the molding shrinkage (after ASM) was measured after molding (ASM: as Mold) for the obtained resin composition, and after the molding, main curing was performed to form a dielectric substrate. The molding shrinkage rate (after PMC) was evaluated under heating conditions (PMC: Post Mold Cure) assuming the production of .
First, a test piece prepared using a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.) at a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 120 seconds. Mold shrinkage (after ASM) was obtained according to K6911.
Furthermore, the obtained test piece was heat-treated at 175° C. for 4 hours, and the molding shrinkage (after ASM) was measured according to JIS K 6911.

(Evaluation of permittivity and dielectric loss tangent by cavity resonator method)
First, a test piece was obtained using the resin composition.
Specifically, the resin compositions prepared in Examples and Comparative Examples were applied to a Si substrate and prebaked at 120° C. for 4 minutes to form a resin film having a coating thickness of 12 μm.
This was heated in an oven at 200° C. for 90 minutes in a nitrogen atmosphere and hydrofluoric acid treatment (immersed in a 2 mass % hydrofluoric acid aqueous solution). After removing the substrate from the hydrofluoric acid, the cured film was peeled off from the Si substrate and used as a test piece.
A network analyzer HP8510C, a synthesized sweeper HP83651A, and a test set HP8517B (all manufactured by Agilent Technologies) were used as measuring devices. These devices and a cylindrical cavity resonator (inner diameter φ42 mm, height 30 mm) were set up.
The resonance frequency, 3 dB bandwidth, transmitted power ratio, etc. were measured at a frequency of 5 GHz with and without inserting the test piece into the resonator. Then, by analytically calculating these measurement results with software, the dielectric properties such as dielectric constant (Dk) and dielectric loss tangent (Df) were obtained. The measurement mode was TE ₀₁₁ mode.

As shown in Tables 1 and 2, by using a phenolic resin and an active ester resin together as a curing agent and using a resin composition for semiconductor encapsulation containing a predetermined curing accelerator, the shrinkage rate during molding is reduced. Further, it was confirmed that the cured product obtained from the composition, which was expected to have a low yield and excellent product yield, has excellent mechanical strength and dielectric properties. That is, it was confirmed that the resin composition for semiconductor encapsulation of the present invention has an excellent balance of these properties.

This application claims priority based on Japanese Patent Application No. 2021-117662 filed on July 16, 2021, and the entire disclosure thereof is incorporated herein.

20 semiconductor element 30 substrate 32 die pad 34 outer lead 40 wire 50 sealing material 60 solder ball 100 semiconductor device

Claims (14)

(A) an epoxy resin;
(B) a curing agent;
(C) a curing accelerator, and a resin composition for semiconductor encapsulation,
The curing agent (B) contains a phenol resin (B1) and an active ester resin (B2),
The active ester resin (B2) has a structure represented by the general formula (1),

(In general formula (1), A is a substituted or unsubstituted arylene group linked via an aliphatic cyclic hydrocarbon group,
Ar' is a substituted or unsubstituted aryl group;
k is the average value of the repeating units and ranges from 0.25 to 3.5;
In general formula (1), B is a structure represented by general formula (B),

(In the general formula (B), Ar is a substituted or unsubstituted arylene group, Y is a single bond, a substituted or unsubstituted linear alkylene group having 1 to 6 carbon atoms, or a substituted or unsubstituted is a cyclic alkylene group having 3 to 6 carbon atoms, a substituted or unsubstituted divalent aromatic hydrocarbon group, an ether bond, a carbonyl group, a carbonyloxy group, a sulfide group, or a sulfone group, n is 0 is an integer between ~4.)
Curing accelerator (C) is tetraphenylphosphonium-4,4'-sulfonyldiphenolate, tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate, 4-hydroxy-2-(triphenylphosphonium)phenolate. A semiconductor encapsulating resin composition comprising one or more selected from the group consisting of: The resin composition for semiconductor encapsulation according to claim 1,
The resin composition for semiconductor encapsulation, wherein the structure represented by the general formula (B) is at least one selected from the general formulas (B-1) to (B-6).

(In general formulas (B-1) to (B-6), R ¹ is each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group, each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and X is a linear alkylene group having 2 to 6 carbon atoms; a group, an ether bond, a carbonyl group, a carbonyloxy group, a sulfide group, or a sulfone group,
n is an integer of 0-4 and p is an integer of 1-4. ) The resin composition for semiconductor encapsulation according to claim 1 or 2,
A resin composition for semiconductor encapsulation, wherein in the general formula (1), A has a structure represented by the general formula (A).

(In general formula (A), each R ³ is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or an aralkyl group, and l is 0 or 1, and m is an integer of 1 or more) The resin composition for semiconductor encapsulation according to any one of claims 1 to 3,
A resin composition for semiconductor encapsulation, wherein the ratio of the content of the phenol resin (B1) to the content of the active ester resin (B2) is 25:75 to 75:25. The resin composition for semiconductor encapsulation according to any one of claims 1 to 4,
A resin composition for semiconductor encapsulation, further comprising a coupling agent (D). The resin composition for semiconductor encapsulation according to claim 5,
A resin composition for semiconductor encapsulation, wherein the coupling agent (D) is a secondary aminosilane coupling agent. The resin composition for semiconductor encapsulation according to any one of claims 1 to 6, wherein at least one of the epoxy resin (A) and the phenol resin (B1) has a biphenylaralkyl structure. thing. The resin composition for semiconductor encapsulation according to any one of claims 1 to 7, wherein the phenolic resin (B1) has a biphenylaralkyl structure. The resin composition for semiconductor encapsulation according to any one of claims 1 to 8,
A resin composition for semiconductor encapsulation, wherein the epoxy resin (A) contains at least one selected from biphenylaralkyl-type resins and dicyclopentadiene-type resins. The resin composition for semiconductor encapsulation according to any one of claims 1 to 9,
A resin composition for semiconductor encapsulation, further comprising a silicone oil (E). The resin composition for semiconductor encapsulation according to any one of claims 1 to 10,
A resin composition for semiconductor encapsulation, further comprising an inorganic filler (F). The resin composition for semiconductor encapsulation according to claim 11,
A resin composition for semiconductor encapsulation, wherein the inorganic filler (F) is at least one selected from silica, alumina, talc, titanium oxide, silicon nitride and aluminum nitride. The resin composition for semiconductor encapsulation according to any one of claims 1 to 12,
A resin composition for semiconductor encapsulation, wherein the gel time of the resin composition for semiconductor encapsulation is 50 seconds or more and 80 seconds or less. a semiconductor element;
A sealing material for sealing the semiconductor element, comprising a cured product of the semiconductor sealing resin composition according to any one of claims 1 to 13;
A semiconductor device comprising:

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