JP6750659B2 - Sealing resin composition and semiconductor device - Google Patents

Description

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

In order to improve reliability in a semiconductor device including a bonding wire, various studies have been made on a resin composition for sealing. As such a technique, for example, the technique described in Patent Document 1 can be cited.

Patent Document 1 describes an epoxy resin composition for semiconductor encapsulation containing a biphenyl type epoxy resin having a hydrolyzable chlorine content of 10 to 20 ppm.

JP, 2013-67694, A

A semiconductor device obtained by encapsulating a semiconductor element and a bonding wire, which is connected to the semiconductor element and contains Cu as a main component, with a cured product of a resin composition for encapsulation is required to have improved reliability. Has been.

According to the invention,
A resin composition for encapsulation used for encapsulating a semiconductor element and a bonding wire connected to the semiconductor element and made of a metal material having a Cu content of 99.9% by mass or more. There
Epoxy resin,
Hardener,
An ion scavenger,
A coupling agent,
A filler,
Including,
Does not contain aluminum hydroxide,
The coupling agent includes mercaptosilane,
The content of the coupling agent with respect to the entire solid content of the resin composition for sealing is 0.05% by mass or more and 0.5% by mass or less,
The content of the ion scavenger with respect to the entire solid content of the sealing resin composition is 0.05 mass% or more and 0.5 mass% or less,
And _{pH (1)} measured under the following conditions 1, and _{pH (2)} as measured under the following conditions 2, the difference _{(pH (1) -pH (2} )) is 0.1 to 1.1 The resin composition for sealing which is
(Condition 1: A cured product obtained by thermally curing the encapsulating resin composition under the conditions of 175° C. for 4 hours is pulverized to obtain a pulverized product. Next, 5 g of the pulverized product immediately after pulverization is diluted with 50 ml of pure water. After putting in the water, the pure water is subjected to hot water extraction treatment at 125° C. for 20 hours, and the pH (pH ₍₁₎ ) of the obtained extract is measured)
(Condition 2: The encapsulating resin composition is thermally cured under the conditions of 175° C. for 4 hours to pulverize a cured product to obtain a pulverized product. Then, the pulverized product is stored at 175° C. for 500 hours. Next, 5 g of the crushed product after storage was put into 50 ml of pure water, and the pure water was subjected to hot water extraction treatment at 125° C. for 20 hours to obtain a pH ( pH ₍₂₎ ) is measured)

According to the invention,
Semiconductor element,
A bonding wire which is connected to the semiconductor element and contains Cu as a main component;
A sealing resin constituted by a cured product of the above-mentioned sealing resin composition, and sealing the semiconductor element and the bonding wire,
There is provided a semiconductor device comprising:

According to the present invention, the reliability of the semiconductor device can be improved.

It is sectional drawing which shows the semiconductor device which concerns on this embodiment.

Hereinafter, embodiments will be described with reference to the drawings. In all the drawings, the same constituents will be referred to with the same numerals, and the description thereof will not be repeated.

FIG. 1 is a sectional view showing a semiconductor device 100 according to this embodiment.
The encapsulating resin composition according to the present embodiment is a encapsulating resin composition used for encapsulating a semiconductor element and a bonding wire containing Cu as a main component, which is connected to the semiconductor element. It contains an epoxy resin and a curing agent. In addition, the encapsulating resin composition has a difference (pH ₍₁₎ -pH _{(2) )} between pH ₍₁₎ measured under the following condition ₁ and pH ₍₂₎ measured under the following condition 2. ) Is 1.1 or less.
(Condition 1: A cured product obtained by thermally curing the encapsulating resin composition under the conditions of 175° C. for 4 hours is pulverized to obtain a pulverized product. Next, 5 g of the pulverized product immediately after pulverization is diluted with 50 ml of pure water. After being placed in the above, the pure water is subjected to hot water extraction treatment at 125° C. for 20 hours, and the pH (pH ₍₁₎ ) of the obtained extract is measured)
(Condition 2: The encapsulating resin composition is thermally cured under the conditions of 175° C. for 4 hours to pulverize a cured product to obtain a pulverized product. Then, the pulverized product is stored at 175° C. for 500 hours. Next, after putting 5 g of the pulverized product after storage in 50 ml of pure water, the pure water was subjected to hot water extraction treatment under the conditions of 125° C. for 20 hours, and the pH of the obtained extract solution ( pH ₍₂₎ ) is measured)

High-temperature storage characteristics are one of the indicators of the reliability of semiconductor devices. The high temperature storage characteristics can be evaluated based on, for example, the connectivity of a bonding wire containing Cu as a main component and a semiconductor element after being stored in a high temperature environment. However, there is a concern that it will be difficult to maintain good connectivity between the bonding wire and the semiconductor element during high temperature storage for a long time of, for example, 1000 hours. Therefore, further improvement in high temperature storage characteristics has been demanded so that good connectivity can be maintained even during high temperature storage for a long time.

The present inventor diligently studied a sealing resin composition capable of improving high-temperature storage characteristics. As a result, by controlling the difference (pH ₍₁₎ -pH ₍₂₎ ) between the pH ₍₁₎ measured under the above condition ₁ and the pH ₍₂₎ measured under the above condition 2, high temperature storage It was newly discovered that the characteristics can be improved. The present embodiment realizes a sealing resin composition having (pH ₍₁₎ -pH ₍₂₎ ) of 1.1 or less based on such knowledge. This can improve the high-temperature storage characteristics of the semiconductor device manufactured using the encapsulating resin composition. Therefore, the reliability of the semiconductor device can be improved.

Hereinafter, the semiconductor device 100 including the encapsulating resin composition according to the present embodiment and the encapsulating resin 50 composed of the cured product of the encapsulating resin composition will be described in detail.

First, the encapsulating resin composition will be described.
The encapsulating resin composition is used for encapsulating a semiconductor element and a bonding wire that is connected to the semiconductor element and contains Cu as a main component. In the present embodiment, a case where a semiconductor package is formed by encapsulating a semiconductor element and a bonding wire with an encapsulating resin composed of a cured product of an encapsulating resin composition is exemplified.

The semiconductor element is mounted on a base material such as a die pad or an organic substrate forming a lead frame, or on another semiconductor element. At this time, the semiconductor element is electrically connected to the outer lead, the organic substrate, or another semiconductor element forming the lead frame via the bonding wire. The bonding wire is connected to, for example, an electrode pad provided on the semiconductor element. At least the surface of the electrode pad of the semiconductor element is made of, for example, a metal material containing Al as a main component.

The bonding wire is made of a metal material whose main component is Cu. As such a metal material, for example, a metal material composed of a simple substance of Cu or an alloy material containing Cu as a main component and containing another metal can be used.
In the present embodiment, using a bonding wire made of a metal material having a Cu content of 99.9% by mass or more is an example of a preferable aspect from the viewpoint of cost reduction and the like. In general, when using such a Cu wire, it may be difficult to improve the high temperature storage characteristics of the semiconductor device. However, according to the present embodiment, by controlling (pH ₍₁₎ -pH ₍₂₎ ) as described below, excellent high temperature storage characteristics can be obtained even when using the Cu wire as described above. Can be realized.

The encapsulating resin composition has a difference (pH ₍₁₎ -pH ₍₂₎ ) between the pH ₍₁₎ measured under the following condition ₁ and the pH ₍₂₎ measured under the following condition 2. It is 1.1 or less. Thereby, as described above, the high temperature storage characteristics of the semiconductor device can be improved.

(Condition 1)
The encapsulating resin composition is thermally cured under the conditions of 175° C. for 4 hours to pulverize a cured product to obtain a pulverized product. Next, 5 g of the pulverized product immediately after pulverization was put into 50 ml of pure water, and the pure water was subjected to a hot water extraction treatment under the conditions of 125° C. for 20 hours to obtain a pH (pH _{( 1)} Measure).

(Condition 2)
The encapsulating resin composition is thermally cured under the conditions of 175° C. for 4 hours to pulverize a cured product to obtain a pulverized product. Then, the pulverized product is stored at 175° C. for 500 hours. Next, after putting 5 g of the crushed product after storage in 50 ml of pure water, the pure water was subjected to a hot water extraction treatment under the conditions of 125° C. for 20 hours, and the pH (pH _{( 2)} Measure).

In the above Condition 1 and Condition 2, for the pulverization treatment of the cured product, for example, TI-100 (manufactured by CMT Co., Ltd.) was used, 5.2 g of the cured product was placed in a pulverization kettle and pulverized for 2 minutes. This can be done by Further, in the above Condition 1 and Condition 2, the hot water extraction treatment can be performed using, for example, a pressure resistant container whose inner container is made of polytetrafluoroethylene and whose outer container is made of metal. Further, under the above condition 2, the crushed product is not particularly limited to be stored, but for example, it is carried out by placing a closed container containing the resin composition for sealing in a clean oven maintained at a temperature of 175°C. Is possible.

From the viewpoint of more effectively improving the high temperature storage characteristics of the semiconductor device, (pH ₍₁₎ -pH ₍₂₎ ) is more preferably 0.8 or less, and particularly preferably 0.6 or less. .. The lower limit of (pH ₍₁₎ -pH ₍₂₎ ) is not particularly limited, but may be 0.1, for example.

In the present embodiment, the pH ₍₁₎ of the encapsulating resin composition measured under the above condition 1 is preferably 5 or more and 7 or less, and more preferably 5 or more and 6.5 or less. This makes it possible to more effectively improve the balance of various characteristics required for the encapsulating resin composition, such as high-temperature storage characteristics and reflow resistance. Therefore, it is possible to contribute to the improvement of the reliability of the semiconductor device obtained by using the sealing resin composition.

In the present embodiment, the pH ₍₁₎ , pH ₍₂₎ , and (pH ₍₁₎ -pH ₍₂₎ ) of the encapsulating resin composition are, for example, the types of each component contained in the encapsulating resin composition. The content can be controlled by appropriately adjusting the content, the content, the method for preparing the encapsulating resin composition, and the like. An example of the method for preparing this encapsulating resin composition is surface treatment with a coupling agent (D) for the filler (C) described below.

The encapsulating resin composition contains an epoxy resin (A) and a curing agent (B). This makes it possible to form a sealing resin for sealing the bonding wire and the semiconductor element using the sealing resin composition.

((A) Epoxy resin)
As the epoxy resin (A), general monomers, oligomers and polymers having two or more epoxy groups in one molecule can be used, and the molecular weight and the molecular structure thereof are not particularly limited.
In this embodiment, the epoxy resin (A) is, for example, a biphenyl type epoxy resin; a bisphenol type epoxy resin such as a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, or a tetramethylbisphenol F type epoxy resin; a stilbene type epoxy resin; a phenol. Novolac type epoxy resins, cresol novolac type epoxy resins and other novolac type epoxy resins; triphenol methane type epoxy resins, polyfunctional epoxy resins such as alkyl-modified triphenol methane type epoxy resins; phenol aralkyl type epoxy resins having phenylene skeleton, biphenylene Aralkyl type epoxy resin such as phenol aralkyl type epoxy resin having a skeleton; dihydroxynaphthalene type epoxy resin, naphthalene type epoxy resin such as epoxy resin obtained by converting dimer of dihydroxynaphthalene into glycidyl ether; triglycidyl isocyanurate, monoallyl One or more selected from triazine nucleus-containing epoxy resins such as diglycidyl isocyanurate; bridged cyclic hydrocarbon compound-modified phenol type epoxy resins such as dicyclopentadiene modified phenol type epoxy resins can be contained. Among these, it is more preferable to contain one kind or two or more kinds of the naphthalene type epoxy resin, the aralkyl type epoxy resin, and the biphenyl type epoxy resin, and it is particularly preferable to contain the aralkyl type epoxy resin. The aralkyl type epoxy resin, the biphenyl type epoxy resin, the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, the bisphenol type epoxy resin such as the tetramethylbisphenol F type epoxy resin, and the stilbene type epoxy resin have crystallinity. It is preferably one.

As the epoxy resin (A), an epoxy resin represented by the following formula (1), an epoxy resin represented by the following formula (2), an epoxy resin represented by the following formula (3), and a formula (4) below. It is more preferable to use a resin containing at least one selected from the group consisting of epoxy resins represented by. Among these, those containing at least one of the epoxy resin represented by the following formula (1), the epoxy resin represented by the following formula (2), and the epoxy resin represented by the following formula (4) It is particularly preferable to use.

（式（１）中、Ａｒ^１はフェニレン基またはナフチレン基を表し、Ａｒ^１がナフチレン基の場合、グリシジルエーテル基はα位、β位のいずれに結合していてもよい。Ａｒ^２はフェニレン基、ビフェニレン基またはナフチレン基のうちのいずれか１つの基を表す。Ｒ_ａおよびＲ_ｂは、それぞれ独立に炭素数１〜１０の炭化水素基を表す。ｇは０〜５の整数であり、ｈは０〜８の整数である。ｎ^３は重合度を表し、その平均値は１〜３である）

(In the formula (1), Ar ¹ represents a phenylene group or a naphthylene group. When Ar ¹ is a naphthylene group, the glycidyl ether group may be bonded to either the α-position or the β-position. Ar ² is a phenylene group. , A biphenylene group or a naphthylene group, R _a and R _b each independently represent a hydrocarbon group having 1 to 10 carbon atoms, g is an integer of 0 to 5, and h is an integer of 0 to 8 .n ³ denote the degree of polymerization, the average value is 1-3)

（式（２）中、複数存在するＲ_ｃは、それぞれ独立に水素原子または炭素数１〜４の炭化水素基を表す。ｎ^５は重合度を表し、その平均値は０〜４である）

(In the formula (2), a plurality of R _c's each independently represent a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms. n ⁵ represents a degree of polymerization, and the average value thereof is 0 to 4).

（式（３）中、複数存在するＲ_ｄおよびＲ_ｅは、それぞれ独立に水素原子又は炭素数１〜４の炭化水素基を表す。ｎ^６は重合度を表し、その平均値は０〜４である）

(In the formula (3), a plurality of R _d and R _e each independently represent a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms. n ⁶ represents a degree of polymerization, and its average value is 0 to 4; Is)

（式（４）中、Ｒ_ｆはそれぞれ独立して水素または炭素数１〜４の炭化水素基を表し、Ｒ_ｇはそれぞれ独立して炭素数１〜４の炭化水素基を表す。ａおよびｂは０または１の整数であり、ｃは０〜５の整数である）

(In the formula (4), R _f's each independently represent hydrogen or a hydrocarbon group having 1 to 4 carbon atoms, and R _g's each independently represent a hydrocarbon group having 1 to 4 carbon atoms. a and b Is an integer of 0 or 1 and c is an integer of 0-5)

The content of the epoxy resin (A) in the encapsulating resin composition is, for example, preferably 1% by mass or more, and more preferably 2% by mass or more, based on the entire encapsulating resin composition. It is particularly preferable that the content is 5% by mass or more. By setting the content of the epoxy resin (A) to be the above lower limit value or more, the fluidity of the encapsulating resin composition can be improved. Further, it becomes possible to more reliably suppress the breakage of the bonding wire due to the increase in the viscosity of the sealing resin composition. On the other hand, the content of the epoxy resin (A) in the encapsulating resin composition is, for example, preferably 50% by mass or less, and preferably 30% by mass or less, based on the entire encapsulating resin composition. More preferably, it is particularly preferably 20% by mass or less. By setting the content of the epoxy resin (A) to the above upper limit value or less, it is possible to improve the moisture resistance reliability and the reflow resistance of the semiconductor device.

((B) curing agent)
The curing agent (B) contained in the encapsulating resin composition can be roughly classified into three types, for example, a polyaddition type curing agent, a catalyst type curing agent, and a condensation type curing agent.

Examples of the polyaddition type curing agent used for the curing agent (B) include diethylenetriamine (DETA), triethylenetetramine (TETA), aliphatic polyamines such as metaxylylenediamine (MXDA), diaminodiphenylmethane (DDM), In addition to aromatic polyamines such as m-phenylenediamine (MPDA) and diaminodiphenyl sulfone (DDS), polyamine compounds containing dicyandiamide (DICY), organic acid dihydralazide, and the like; hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride ( Acid anhydrides containing alicyclic acid anhydrides such as MTHPA), trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), aromatic acid anhydrides such as benzophenonetetracarboxylic acid (BTDA); novolak type Phenolic resin-based curing agents such as phenolic resins and polyvinyl phenols; polymercaptan compounds such as polysulfides, thioesters and thioethers; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; organic acids such as carboxylic acid-containing polyester resins.

Examples of the catalyst-type curing agent used as the curing agent (B) include tertiary amine compounds such as benzyldimethylamine (BDMA) and 2,4,6-trisdimethylaminomethylphenol (DMP-30); 2-methyl Examples thereof include imidazole compounds such as imidazole and 2-ethyl-4-methylimidazole (EMI24); Lewis acids such as BF3 complex.

Examples of the condensation-type curing agent used as the curing agent (B) include a resol-type phenol resin; a urea resin such as a methylol group-containing urea resin; and a melamine resin such as a methylol group-containing melamine resin.

Among these, a phenol resin-based curing agent is preferable from the viewpoint of improving the balance of flame resistance, moisture resistance, electrical characteristics, curability, storage stability, and the like. As the phenol resin-based curing agent, any of monomers, oligomers and polymers having two or more phenolic hydroxyl groups in one molecule can be used, and its molecular weight and molecular structure are not particularly limited.
Examples of the phenol resin-based curing agent used as the curing agent (B) include novolac type resins such as phenol novolac resin, cresol novolac resin, and bisphenol novolac resin; polyvinylphenol; polyfunctional phenol resins such as triphenolmethane type phenol resin; terpenes. Modified phenol resin such as modified phenol resin and dicyclopentadiene modified phenol resin; aralkyl type resin such as phenol aralkyl resin having phenylene skeleton and/or biphenylene skeleton, naphthol aralkyl resin having phenylene and/or biphenylene skeleton; bisphenol A, bisphenol One or more selected from bisphenol compounds such as F can be included. Among these, from the viewpoint of improving the balance between reflow resistance and high-temperature storage characteristics, it is preferable to include at least one of an aralkyl type resin and a polyfunctional phenol resin.

It is particularly preferable that the curing agent (B) contains at least one curing agent selected from the group consisting of the compound represented by the following formula (5) and the compound represented by the following formula (6).

（式（５）中、Ａｒ^３はフェニレン基またはナフチレン基を表し、Ａｒ^３がナフチレン基の場合、水酸基はα位、β位のいずれに結合していてもよい。Ａｒ^４は、フェニレン基、ビフェニレン基またはナフチレン基のうちのいずれか１つの基を表す。Ｒ^ｎおよびＲ^ｍは、それぞれ独立に炭素数１〜１０の炭化水素基を表す。ｉは０〜５の整数であり、ｊは０〜８の整数である。ｎ^４は重合度を表し、その平均値は１〜３である）

(In formula (5), Ar ³ represents a phenylene group or a naphthylene group, and when Ar ³ is a naphthylene group, the hydroxyl group may be bonded to either the α-position or the β-position. Ar ⁴ is a phenylene group, It represents any one of a biphenylene group and a naphthylene group, R ⁿ and R ^m each independently represent a hydrocarbon group having 1 to 10 carbon atoms, i is an integer of 0 to 5, and j is j. It is an integer of 0 to 8. n ⁴ represents the degree of polymerization, and its average value is 1 to 3).

（式（６）中、複数存在するＲ_ｈは、それぞれ独立に水素原子又は炭素数１〜４の炭化水素基を表す。ｎ^８は重合度を表し、その平均値は０〜４である）

(In formula (6), a plurality of R _h each independently represent a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms. n ⁸ represents a degree of polymerization, and its average value is 0 to 4)

The content of the curing agent (B) in the encapsulating resin composition is, for example, preferably 2% by mass or more, and more preferably 3% by mass or more, based on the entire encapsulating resin composition. It is particularly preferable that the content is 4% by mass or more. By setting the content of the curing agent (B) to the above lower limit value or more, a sealing resin composition having sufficient fluidity can be realized and moldability can be improved. On the other hand, the content of the curing agent (B) in the encapsulating resin composition is, for example, preferably 15% by mass or less, and preferably 13% by mass or less, based on the entire encapsulating resin composition. More preferably, it is particularly preferably 11% by mass or less. By setting the content of the curing agent (B) to the upper limit value or less, the moisture resistance reliability and reflow resistance of the semiconductor device can be improved.

((C) Filler)
The encapsulating resin composition can further include a filler (C), for example. As the filler (C), those used in general epoxy resin compositions for semiconductor encapsulation can be used, for example, fused spherical silica, fused crushed silica, crystalline silica, talc, alumina, titanium white, nitride. Examples thereof include inorganic fillers such as silicon and organic fillers such as organosilicone powder and polyethylene powder. Of these, it is particularly preferable to use fused spherical silica. These fillers may be used alone or in combination of two or more.
Moreover, the shape of the filler (C) is not particularly limited, but from the viewpoint of increasing the content of the filler while suppressing an increase in the melt viscosity of the encapsulating resin composition, it is as spherical as possible and has a particle size. It is preferred that the distribution is broad.

The content of the filler (C) in the encapsulating resin composition is, for example, preferably 35% by mass or more, and more preferably 50% by mass or more, based on the entire encapsulating resin composition. , 65% by mass or more is particularly preferable. By setting the content of the filler (C) to the above lower limit value or more, low hygroscopicity and low thermal expansion can be improved, and moisture resistance reliability and reflow resistance can be more effectively improved. On the other hand, the content of the filler (C) in the encapsulating resin composition is preferably 95 mass% or less, more preferably 93 mass% or less, and 90 mass% or less. Particularly preferred. By controlling the content of the filler (C) to be not more than the above upper limit, it is possible to suppress a decrease in moldability due to a decrease in fluidity of the encapsulating resin composition and a bonding wire flow due to an increase in viscosity. It becomes possible.

((D) Coupling agent)
The filler (C) can be surface-treated with the coupling agent (D). Examples of the coupling agent (D) include various silane compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, vinylsilane, and methacrylsilane, titanium compounds, aluminum chelates, and aluminum/zirconium compounds. A known coupling agent can be used. These are exemplified by vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxy. Silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane , Vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-anilinopropyltrimethoxysilane, γ-anilinopropylmethyldimethoxysilane, γ-[bis(β-hydroxyethyl) ] Aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)- γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-(β-aminoethyl)aminopropyldimethoxymethylsilane, N-(trimethoxysilylpropyl)ethylenediamine, N-(dimethoxymethylsilyl Isopropyl)ethylenediamine, methyltrimethoxysilane, dimethyldimethoxysilane, methyltriethoxysilane, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilane , Vinyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propyl Silane coupling agents such as amine hydrolysates, isopropyl triisostearoyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctyl bis(ditridecyl phosphite) Titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate, bis(dioctylpa) (Irophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tridodecylbenzene sulfonyl titanate, isopropyl isostearoyl diacrylic titanate, isopropyl tri(dioctyl phosphate) titanate , Titanate-based coupling agents such as isopropyl tricumyl phenyl titanate and tetraisopropyl bis(dioctyl phosphite) titanate. These may be used alone or in combination of two or more. Among these, silane compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane or vinylsilane are more preferable. Further, from the viewpoint of improving the reliability of the semiconductor device such as reflow resistance, it is particularly preferable to use mercaptosilane.

The surface treatment of the filler (C) with the coupling agent (D) can be performed, for example, as follows. First, after charging the filler (C) into the mixer, stirring is started, the coupling agent (D) is further charged therein, and these are stirred for 1 to 5 minutes to obtain the filler (C) and the coupling agent. A mixture of (D) is obtained. The mixture is then removed from the mixer and left to stand. The leaving time can be appropriately selected and can be set to, for example, 3 minutes to 1 hour. As a result, the filler (C) surface-treated with the coupling agent (D) is obtained. Further, the filler (C) after the standing treatment may be further heat-treated. The heat treatment can be performed, for example, under the conditions of 30 to 80° C. and 0.1 to 10 hours. Furthermore, in the present embodiment, the filler (C) is stirred by spraying the coupling agent (D) onto the filler (C) in the mixer using a sprayer. And a mixture of coupling agent (D) may be obtained. As the atomizer, for example, a device equipped with a two-fluid nozzle or the like and capable of atomizing fine droplets can be used. By using such an atomizer, the surface of the filler (C) is more uniformly treated with the coupling agent (D), which is preferable.
In the present embodiment, the pH ₍₁₎ , pH ₍₂₎ , and (pH ₍₁₎ -pH ₍₂₎ ) of the encapsulating resin composition are controlled, for example, by adjusting the conditions of the surface treatment. be able to. The conditions for this surface treatment include, for example, whether or not a sprayer is used, the standing time, the presence or absence of heat treatment, and heat treatment conditions.

In addition, the coupling agent (D) is directly charged into a mixer and mixed with other components, except when the coupling agent (D) is contained in the encapsulating resin composition by performing the surface treatment on the filler (C). By doing so, it may be contained in the resin composition for sealing.

The content of the coupling agent (D) in the encapsulating resin composition is, for example, preferably 0.05% by mass or more, and 0.1% by mass or more, based on the entire encapsulating resin composition. It is more preferable that the amount is 0.15 mass% or more, and it is particularly preferable. When the content of the coupling agent (D) is at least the above lower limit value, the dispersibility of the filler (C) in the encapsulating resin composition can be improved. Therefore, it is possible to more effectively improve the moisture resistance reliability, the reflow resistance, and the like. On the other hand, the content of the coupling agent (D) in the encapsulating resin composition is, for example, preferably 2% by mass or less, more preferably 1% by mass or less, and 0.5% by mass or less. Is particularly preferable. By setting the content of the coupling agent (D) to the above upper limit value or less, the fluidity of the encapsulating resin composition can be improved, and the moldability can be improved.

((E) Ion scavenger)
The encapsulating resin composition can further include, for example, an ion scavenger (E).
The ion scavenger (E) is not particularly limited, and examples thereof include inorganic ion exchangers such as hydrotalcites and polyvalent metal acid salts. These may be used alone or in combination of two or more. Among these, it is particularly preferable to use hydrotalcites from the viewpoint of improving the high temperature storage characteristics.

The content of the ion scavenger (E) in the encapsulating resin composition is, for example, preferably 0.05% by mass or more, and 0.1% by mass or more, based on the entire encapsulating resin composition. It is more preferable that the amount is 0.15 mass% or more, and it is particularly preferable. By setting the content of the ion scavenger (E) to be the lower limit value or more, the high temperature storage characteristics can be more effectively improved. In addition, corrosion between the bonding wire and the semiconductor element can be surely suppressed, and good connection reliability can be maintained. On the other hand, the content of the ion scavenger (E) in the sealing resin composition is, for example, preferably 1% by mass or less, more preferably 0.8% by mass or less, and 0.5% by mass. % Or less is particularly preferable. By setting the content of the ion scavenger (E) to be not more than the above upper limit, it is possible to improve the moisture resistance reliability and the reflow resistance of the semiconductor device.

(Curing accelerator (F))
The encapsulating resin composition can include, for example, a curing accelerator (F). The curing accelerator (F) may be any agent that promotes a crosslinking reaction between the epoxy group of the epoxy resin (A) and the curing agent (B) (for example, a phenolic hydroxyl group of a phenol resin curing agent), For example, those used for general epoxy resin compositions for sealing can be used.

In the present embodiment, the curing accelerator (F) contains a phosphorus atom such as an organic phosphine, a tetra-substituted phosphonium compound, a phosphobetaine compound, an adduct of a phosphine compound and a quinone compound, an adduct of a phosphonium compound and a silane compound, and the like. Compounds: 1,8-diazabicyclo(5,4,0)undecene-7, benzyldimethylamine, 2-methylimidazole, and the like, such as amidines and tertiary amines, nitrogen atoms containing quaternary salts of the amidines and amines It may contain one kind or two or more kinds selected from the compounds. Among these, it is more preferable to include a phosphorus atom-containing compound from the viewpoint of improving curability. Further, from the viewpoint of improving the balance between moldability and curability, it has latent properties such as tetra-substituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, and adducts of phosphonium compounds and silane compounds. It is more preferable to include those.

Examples of the organic phosphine that can be used in the encapsulating resin composition include a first phosphine such as ethylphosphine and phenylphosphine; a second phosphine such as dimethylphosphine and diphenylphosphine; trimethylphosphine, triethylphosphine, tributylphosphine, and triphenyl. A third phosphine such as phosphine may be mentioned.

Examples of the tetra-substituted phosphonium compound that can be used in the encapsulating resin composition include compounds represented by the following general formula (7).

（上記一般式（７）において、Ｐはリン原子を表す。Ｒ^４、Ｒ^５、Ｒ^６およびＲ^７は芳香族基またはアルキル基を表す。Ａはヒドロキシル基、カルボキシル基、チオール基から選ばれる官能基のいずれかを芳香環に少なくとも１つ有する芳香族有機酸のアニオンを表す。ＡＨはヒドロキシル基、カルボキシル基、チオール基から選ばれる官能基のいずれかを芳香環に少なくとも１つ有する芳香族有機酸を表す。ｘ、ｙは１〜３の数、ｚは０〜３の数であり、かつｘ＝ｙである。）

(In the general formula (7), P represents a phosphorus atom. R ⁴ , R ⁵ , R ⁶ and R ⁷ represent an aromatic group or an alkyl group. A is selected from a hydroxyl group, a carboxyl group and a thiol group. AH represents an anion of an aromatic organic acid having at least one functional group in the aromatic ring, wherein AH is an aromatic having at least one functional group selected from a hydroxyl group, a carboxyl group and a thiol group in the aromatic ring. Represents an organic acid, x and y are numbers 1 to 3, z is a number 0 to 3, and x=y.)

The compound represented by the general formula (7) can be obtained, for example, as follows, but is not limited thereto. First, a tetra-substituted phosphonium halide, an aromatic organic acid, and a base are mixed in an organic solvent and uniformly mixed to generate an aromatic organic acid anion in the solution system. Then, by adding water, the compound represented by the general formula (7) can be precipitated. In the compound represented by the general formula (7), R ⁴ , R ⁵ , R ⁶ and R ⁷ bonded to the phosphorus atom are phenyl groups, and AH is a compound having a hydroxyl group on the aromatic ring, that is, phenols. And A is preferably the anion of the phenols. Examples of the phenols include monocyclic phenols such as phenol, cresol, resorcin, and catechol, condensed polycyclic phenols such as naphthol, dihydroxynaphthalene, and anthraquinol, bisphenols such as bisphenol A, bisphenol F, and bisphenol S, Examples thereof include polycyclic phenols such as phenylphenol and biphenol.

Examples of the phosphobetaine compound that can be used in the encapsulating resin composition include compounds represented by the following general formula (8).

（上記一般式（８）において、Ｒ^８は炭素数１〜３のアルキル基、Ｒ^９はヒドロキシル基を表す。ｆは０〜５の数であり、ｇは０〜３の数である。）

(In the general formula (8), R ⁸ represents an alkyl group having 1 to 3 carbon atoms, and R ⁹ represents a hydroxyl group. f is a number of 0 to 5 and g is a number of 0 to 3.)

The compound represented by the general formula (8) is obtained, for example, as follows. First, it is obtained through a step of bringing a triaromatic-substituted phosphine, which is a third phosphine, into contact with a diazonium salt, and substituting the triaromatic-substituted phosphine with the diazonium group of the diazonium salt. However, it is not limited to this.

Examples of the adduct of the phosphine compound and the quinone compound that can be used in the encapsulating resin composition include compounds represented by the following general formula (9).

（上記一般式（９）において、Ｐはリン原子を表す。Ｒ^１０、Ｒ^１１およびＲ^１２は炭素数１〜１２のアルキル基または炭素数６〜１２のアリール基を表し、互いに同一であっても異なっていてもよい。Ｒ^１３、Ｒ^１４およびＲ^１５は水素原子または炭素数１〜１２の炭化水素基を表し、互いに同一であっても異なっていてもよく、Ｒ^１４とＲ^１５が結合して環状構造となっていてもよい。）

(In the general formula (9), P represents a phosphorus atom. R ¹⁰ , R ¹¹ and R ¹² represent an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms and are the same as each other. R ¹³ , R ¹⁴ and R ¹⁵ represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms and may be the same or different from each other, and R ¹⁴ and R ¹⁵ are bonded to each other. And may have a ring structure.)

Examples of the phosphine compound used for the adduct of the phosphine compound and the quinone compound include aromatic compounds such as triphenylphosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, trinaphthylphosphine, and tris(benzyl)phosphine. Those having a substituent or a substituent such as an alkyl group and an alkoxyl group are preferred, and examples of the substituent such as an alkyl group and an alkoxyl group include those having a carbon number of 1 to 6. From the viewpoint of easy availability, triphenylphosphine is preferable.

Further, examples of the quinone compound used for the adduct of the phosphine compound and the quinone compound include benzoquinone and anthraquinones, and among them, p-benzoquinone is preferable from the viewpoint of storage stability.

As a method for producing an adduct of a phosphine compound and a quinone compound, the adduct can be obtained by contacting and mixing in a solvent in which both the organic tertiary phosphine and the benzoquinone can be dissolved. As the solvent, ketones such as acetone and methyl ethyl ketone, which have low solubility in adducts, are preferable. However, it is not limited to this.

In the compound represented by the general formula (9), R ¹⁰ , R ¹¹ and R ¹² bonded to the phosphorus atom are phenyl groups, and R ¹³ , R ¹⁴ and R ¹⁵ are hydrogen atoms, that is, 1, A compound to which 4-benzoquinone and triphenylphosphine are added is preferable from the viewpoint of lowering the elastic modulus of the cured product of the encapsulating resin composition when heated.

Examples of the adduct of the phosphonium compound and the silane compound that can be used in the encapsulating resin composition include compounds represented by the following general formula (10).

（上記一般式（１０）において、Ｐはリン原子を表し、Ｓｉは珪素原子を表す。Ｒ^１６、Ｒ^１７、Ｒ^１８およびＲ^１９は、それぞれ、芳香環または複素環を有する有機基、あるいは脂肪族基を表し、互いに同一であっても異なっていてもよい。式中Ｒ^２０は、基Ｙ^２およびＹ^３と結合する有機基である。式中Ｒ^２１は、基Ｙ^４およびＹ^５と結合する有機基である。Ｙ^２およびＹ^３は、プロトン供与性基がプロトンを放出してなる基を表し、同一分子内の基Ｙ^２およびＹ^３が珪素原子と結合してキレート構造を形成するものである。Ｙ^４およびＹ^５はプロトン供与性基がプロトンを放出してなる基を表し、同一分子内の基Ｙ^４およびＹ^５が珪素原子と結合してキレート構造を形成するものである。Ｒ^２０およびＲ^２１は互いに同一であっても異なっていてもよく、Ｙ^２、Ｙ^３、Ｙ^４およびＹ^５は互いに同一であっても異なっていてもよい。Ｚ^１は芳香環または複素環を有する有機基、あるいは脂肪族基である。）

(In the general formula (10), P represents a phosphorus atom and Si represents a silicon atom. R ¹⁶ , R ¹⁷ , R ¹⁸ and R ¹⁹ are each an organic group having an aromatic ring or a heterocycle, or a fatty group. R ²⁰ represents a group group and may be the same or different from each other, wherein R ²⁰ is an organic group bonded to the groups Y ² and Y ^{3. In the} formula, R ²¹ is a group Y ⁴ and Y ⁵ . Y ² and Y ³ represent a group formed by a proton-donating group releasing a proton, and the groups Y ² and Y ³ in the same molecule bond with a silicon atom to form a chelate structure. Y ⁴ and Y ⁵ represent groups formed by releasing a proton from a proton donating group, and the groups Y ⁴ and Y ⁵ in the same molecule bond with a silicon atom to form a chelate structure. R ²⁰ and R ²¹ may be the same or different from each other, and Y ² , Y ³ , Y ⁴ and Y ⁵ may be the same or different from each other, Z ¹ is an aromatic ring or It is an organic group having a heterocycle or an aliphatic group.)

In the general formula (10), R ¹⁶ , R ¹⁷ , R ¹⁸ and R ¹⁹ are, for example, phenyl group, methylphenyl group, methoxyphenyl group, hydroxyphenyl group, naphthyl group, hydroxynaphthyl group, benzyl group, methyl group. , An ethyl group, an n-butyl group, an n-octyl group, a cyclohexyl group, and the like. Among these, an alkyl group such as a phenyl group, a methylphenyl group, a methoxyphenyl group, a hydroxyphenyl group, and a hydroxynaphthyl group, an alkoxy group. An aromatic group having a substituent such as a hydroxyl group or an unsubstituted aromatic group is more preferable.

In addition, in the general formula (10), R ²⁰ is an organic group bonded to Y ² and Y ³ . Similarly, R ²¹ is an organic group bonded to the groups Y ⁴ and Y ⁵ . Y ² and Y ³ are groups formed by releasing a proton from a proton donating group, and the groups Y ² and Y ³ in the same molecule bond with a silicon atom to form a chelate structure. Similarly, Y ⁴ and Y ⁵ are groups formed by releasing a proton from a proton donating group, and the groups Y ⁴ and Y ⁵ in the same molecule bond with a silicon atom to form a chelate structure. The groups R ²⁰ and R ²¹ may be the same or different from each other, and the groups Y ² , Y ³ , Y ⁴ and Y ⁵ may be the same or different from each other. In the group represented by —Y ² —R ²⁰ —Y ³ — and —Y ⁴ —R ²¹ —Y ⁵ — in the general formula (10), the proton donor releases two protons. The proton donor is preferably an organic acid having at least two carboxyl groups or hydroxyl groups in the molecule, and further, a carboxyl group or a hydroxyl group at an adjacent carbon atom forming an aromatic ring. Is preferably an aromatic compound having at least two, and more preferably an aromatic compound having at least two hydroxyl groups on adjacent carbons forming an aromatic ring, for example, catechol, pyrogallol, 1,2-dihydroxynaphthalene, 2,3- Dihydroxynaphthalene, 2,2'-biphenol, 1,1'-bi-2-naphthol, salicylic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, chloranilic acid, tannic acid, 2-hydroxy Examples thereof include benzyl alcohol, 1,2-cyclohexanediol, 1,2-propanediol, and glycerin. Among these, catechol, 1,2-dihydroxynaphthalene, and 2,3-dihydroxynaphthalene are more preferable.

Further, Z ¹ in the general formula (10) represents an organic group or an aliphatic group having an aromatic ring or a heterocycle, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, Aliphatic hydrocarbon groups such as hexyl group and octyl group, aromatic hydrocarbon groups such as phenyl group, benzyl group, naphthyl group and biphenyl group, glycidyloxy groups such as glycidyloxypropyl group, mercaptopropyl group and aminopropyl group , A mercapto group, an alkyl group having an amino group, a reactive substituent such as a vinyl group, and the like. Among them, a methyl group, an ethyl group, a phenyl group, a naphthyl group, and a biphenyl group are preferable from the viewpoint of thermal stability. , And more preferable.

As a method for producing an adduct of a phosphonium compound and a silane compound, a flask containing methanol is dissolved by adding a silane compound such as phenyltrimethoxysilane and a proton donor such as 2,3-dihydroxynaphthalene, and then dissolving at room temperature. A sodium methoxide-methanol solution is added dropwise with stirring. Further, a solution prepared by dissolving a tetra-substituted phosphonium halide such as tetraphenylphosphonium bromide prepared in advance in methanol is added dropwise thereto at room temperature with stirring to precipitate crystals. The precipitated crystals are filtered, washed with water, and vacuum dried to obtain an adduct of a phosphonium compound and a silane compound. However, it is not limited to this.

The content of the curing accelerator (F) in the encapsulating resin composition is, for example, preferably 0.05% by mass or more, and 0.1% by mass or more with respect to the entire encapsulating resin composition. Is more preferable. By setting the content of the curing accelerator (F) to the above lower limit value or more, it is possible to suppress deterioration of the curability of the encapsulating resin composition. On the other hand, the content of the curing accelerator (F) in the encapsulating resin composition is, for example, preferably 1% by mass or less, and 0.8% by mass or less, based on the entire encapsulating resin composition. More preferably. By setting the content of the curing accelerator (F) to the above upper limit value or less, it is possible to prevent the fluidity of the encapsulating resin composition from decreasing.

The encapsulating resin composition may further contain, if necessary, colorants such as carbon black and red iron oxide; low stress components such as silicone rubber; natural waxes such as carnauba wax; synthetic waxes; higher fatty acids such as zinc stearate; Releasing agents such as metal salts or paraffin; flame retardants such as aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, and phosphazene; various additives such as antioxidants may be appropriately mixed.

As the sealing resin composition, for example, the above-mentioned components are mixed by a known means, further melt-kneaded by a kneader such as a roll, a kneader or an extruder, cooled, and then pulverized. It is possible to use those whose dispersion degree and fluidity are appropriately adjusted.

Next, the semiconductor device 100 according to this embodiment will be described.
The semiconductor device 100 includes a semiconductor element 20, a bonding wire 40, and a sealing resin 50. The bonding wire 40 is connected to the semiconductor element 20 and contains Cu as a main component. The encapsulating resin 50 is composed of a cured product of the encapsulating resin composition described above, and encapsulates the semiconductor element 20 and the bonding wire 40.

The semiconductor element 20 is mounted on the base material 30. The base material 30 is, for example, a lead frame or an organic substrate. Further, the base material 30 is connected to the bonding wire 40. FIG. 2 illustrates a case where the semiconductor element 20 is mounted on the die pad 32 of the base material 30 which is the lead frame via the die attach material 10. The base material 30, which is a lead frame, is made of, for example, a metal material whose main component is Cu or 42 alloy. The semiconductor element 20 may be arranged on another semiconductor element.

A plurality of electrode pads 22, for example, are formed on the upper surface of the semiconductor element 20. At least the surface layer of the electrode pad 22 provided on the semiconductor element 20 is made of, for example, a metal material containing Al as a main component. Thereby, the connection reliability between the bonding wire 40 containing Cu as a main component and the electrode pad 22 can be improved.
FIG. 1 illustrates the case where the bonding wire 40 electrically connects the electrode pad 22 of the semiconductor element 20 and the outer lead 34 of the base material 30.

The sealing resin 50 is composed of a cured product of the sealing resin composition described above. Therefore, the adhesion to the base material 30 and the bonding wire 40 is good, and the semiconductor device 100 having excellent reflow resistance, moisture resistance reliability, and high temperature operation characteristics can be obtained. This effect is particularly remarkable when the bonding wire 40 is made of a metal material containing Cu as a main component and the base material 30 is made of a metal material containing Cu or 42 alloy as a main component. It is also possible to improve the high temperature storage characteristics of the semiconductor device 100.

The semiconductor device 100 is manufactured, for example, as follows.
First, the semiconductor element 20 is mounted on the base material 30. Next, the base material 30 and the semiconductor element 20 are connected to each other by a bonding wire 40 containing Cu as a main component. Then, the semiconductor element 20 and the bonding wire 40 are sealed with the above-mentioned sealing resin composition. The sealing molding method is not particularly limited, and examples thereof include a transfer molding method and a compression molding method. As a result, the semiconductor device 100 is manufactured.

It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within the scope of achieving the object of the present invention are included in the present invention.
Hereinafter, an example of the reference mode will be additionally described.
1. A sealing resin composition used for sealing a semiconductor element and a bonding wire containing Cu as a main component, which is connected to the semiconductor element,
Epoxy resin,
Hardener,
Including,
And _{pH (1)} measured under the following conditions 1, and _{pH (2)} as measured under the following conditions 2, the difference _{(pH (1) -pH (2} )) is 1.1 or less sealing Resin composition.
(Condition 1: The cured resin obtained by thermally curing the encapsulating resin composition under the conditions of 175° C. for 4 hours is pulverized to obtain a pulverized product. Next, 5 g of the pulverized product immediately after pulverization is diluted with 50 ml of pure water. After putting in the water, the pure water is subjected to hot water extraction treatment at 125° C. for 20 hours, and the pH (pH ₍₁₎ ) of the obtained extract is measured)
(Condition 2: The encapsulating resin composition is thermally cured under the conditions of 175° C. for 4 hours to pulverize a cured product to obtain a pulverized product. Then, the pulverized product is stored at 175° C. for 500 hours. Next, 5 g of the crushed product after storage was put into 50 ml of pure water, and the pure water was subjected to hot water extraction treatment under the conditions of 125° C. for 20 hours to obtain a pH ( pH ₍₂₎ ) is measured)
2. 1. In the encapsulating resin composition according to
A sealing resin composition having a pH ₍₁₎ of 5 or more and 7 or less.
3. 1. Or 2. In the encapsulating resin composition according to
A resin composition for encapsulation, which further comprises an ion scavenger.
4. 3. In the encapsulating resin composition according to
The encapsulating resin composition has a content of the ion scavenger with respect to the entire solid content of the encapsulating resin composition of 0.05% by mass or more and 1% by mass or less.
5. Semiconductor element,
A bonding wire which is connected to the semiconductor element and contains Cu as a main component;
1. ~4. A sealing resin that is composed of a cured product of the sealing resin composition according to any one of the above, and that seals the semiconductor element and the bonding wire,
A semiconductor device comprising:

Next, examples of the present invention will be described.

(Resin composition for sealing)
For each of Examples 1 to 14 and Comparative Examples 1 and 2, a resin composition for encapsulation was prepared as follows. First, the filler (C) was surface-treated with the coupling agent (D) in the blending amount shown in Table 1. Then, according to the formulation shown in Table 1, the respective components were mixed at 15 to 28°C using a mixer. Then, the obtained mixture was roll-kneaded at 70 to 100°C. Then, the mixture after kneading was cooled and pulverized to obtain an epoxy resin composition. The details of each component in Table 1 are as follows. The unit in Table 1 is% by mass.

(A) Epoxy resin Epoxy resin 1: Biphenylene skeleton-containing phenol aralkyl type epoxy resin (NC-3000P, manufactured by Nippon Kayaku Co., Ltd.)
Epoxy resin 2: Biphenyl type epoxy resin (YX4000K, manufactured by Mitsubishi Chemical Corporation)
Epoxy resin 3: naphthalene type epoxy resin (HP-4770, manufactured by DIC Corporation)

(B) Curing agent Curing agent 1: Biphenylene skeleton-containing phenol aralkyl resin (MEH-7851SS, manufactured by Meiwa Kasei Co., Ltd.)
Curing agent 2: Phenylene skeleton-containing phenol aralkyl resin (XLC-4L, manufactured by Mitsui Chemicals, Inc.)
Hardener 3: Triphenol methane type phenol resin (MEH-7500, manufactured by Meiwa Kasei Co., Ltd.)

(C) Filler Filler 1: Silica (average particle size 26 μm, specific surface area 2.4 mm ² /g)
Filler 2: Silica (SO-25R, manufactured by Admatechs Co., Ltd., average particle size 0.5 μm, specific surface area 6.0 mm ² /g)

(D) Coupling agent γ-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-803)

(E) Ion scavenger hydrotalcite (DHT-4H, manufactured by Kyowa Chemical Industry Co., Ltd.)

(F) Curing accelerator Curing accelerator 1: Compound represented by the following formula (11) Curing accelerator 2: Compound represented by the following formula (12)

(Method of synthesizing curing accelerator 1)
A separable flask equipped with a cooling tube and a stirrer was charged with 6.49 g (0.060 mol) of benzoquinone, 17.3 g (0.066 mol) of triphenylphosphine and 40 ml of acetone, and reacted at room temperature with stirring. The precipitated crystals were washed with acetone, filtered and dried to obtain a hardening accelerator 1 of dark green crystals.

(Method of synthesizing curing accelerator 2)
A separable flask equipped with a cooling tube and a stirrer was charged with 12.81 g (0.080 mol) of 2,3-dihydroxynaphthalene, 16.77 g (0.040 mol) of tetraphenylphosphonium bromide and 100 ml of methanol, and stirred to dissolve uniformly. It was A sodium hydroxide solution prepared by previously dissolving 1.60 g (0.04 ml) of sodium hydroxide in 10 ml of methanol was gradually dropped into the flask to precipitate crystals. The precipitated crystal was filtered, washed with water, and vacuum dried to obtain a curing accelerator 2.

(G) Release agent carnauba wax

In Examples 1 to 4, 7 to 14 and Comparative Examples 1 to 2, the surface treatment with the coupling agent (D) with respect to the filler (C) was performed as follows. First, after charging the filler 1 and the filler 2 into the mixer, stirring is started, the coupling agent (D) is further charged therein, and these are stirred for 3.0 minutes to obtain the filler 1 and the filler. A mixture of 2 and the coupling agent (D) was obtained. Next, this mixture was taken out of the mixer and left for the time (standing time) shown in Table 1. As a result, a filler (C) surface-treated with the coupling agent (D) was obtained.
In Example 5, the surface treatment was performed in the same manner as in Example 1 except that after the mixture was allowed to stand, the mixture was heat-treated at 55° C. for 3 hours.
In Example 6, the surface treatment was performed in the same manner as in Example 1 except that the mixture of the filler 1, the filler 2 and the coupling agent (D) was obtained as follows. First, the filler 1 and the filler 2 were put into a mixer to mix them. Then, while spraying the coupling agent (D) on the filler 1 and the filler 2 in the mixer using a sprayer, these are stirred for 3.0 minutes to obtain the filler 1, the filler 2, and the coupling agent. A mixture of (D) was obtained. Next, this mixture was taken out of the mixer and left for the time (standing time) shown in Table 1.

(Measurement of pH ₍₁₎ )
The pH ₍₁₎ of the obtained encapsulating resin composition for each of the examples and the comparative examples was measured as follows. First, a cured product obtained by thermally curing the encapsulating resin composition under the conditions of 175° C. for 4 hours was pulverized to obtain a pulverized product. The crushing treatment was carried out by using TI-100 (manufactured by CMT Co., Ltd.) to put 5.2 g of the cured product in a crushing pot and crushing for 2 minutes. Next, 5 g of the pulverized product immediately after pulverization was put into 50 ml of pure water. Next, this pure water was subjected to hot water extraction treatment under the conditions of 125° C. and 20 hours using a pressure resistant container in which the inner container was made of polytetrafluoroethylene and the outer container was made of metal. The pH of the extract thus obtained was measured with a pH meter and defined as pH ₍₁₎ .

(Measurement of pH ₍₂₎ )
The pH ₍₂₎ of the encapsulating resin composition obtained in each of the examples and the comparative examples was measured as follows. First, a cured product obtained by thermally curing the encapsulating resin composition under the conditions of 175° C. for 4 hours was pulverized to obtain a pulverized product. The crushing treatment was carried out by using TI-100 (manufactured by CMT Co., Ltd.) to put 5.2 g of the cured product in a crushing pot and crushing for 2 minutes. Then, the obtained pulverized product was stored at 175° C. for 500 hours. Next, 5 g of the crushed product after storage was put in 50 ml of pure water. Next, this pure water was subjected to hot water extraction treatment under the conditions of 125° C. and 20 hours using a pressure resistant container in which the inner container was made of polytetrafluoroethylene and the outer container was made of metal. The pH of the extract thus obtained was measured with a pH meter and defined as pH ₍₂₎ .

(Fabrication of semiconductor device)
For each of Examples 1 to 14 and Comparative Examples 1 and 2, semiconductor devices were manufactured as follows.
First, a TEG (Test Element Group) chip (3.5 mm×3.5 mm) provided with an electrode pad made of aluminum was mounted on the die pad portion of the lead frame whose surface was plated with Ag. Next, the electrode pad of the TEG chip (hereinafter referred to as the electrode pad) and the outer lead portion of the lead frame were wire-bonded at a wire pitch of 120 μm using a bonding wire made of a Cu 99.9% metal material. The structure thus obtained is sealed and molded using a resin composition for sealing under conditions of a mold temperature of 175° C., an injection pressure of 10.0 MPa and a curing time of 2 minutes using a low pressure transfer molding machine, A semiconductor package was manufactured. Then, the obtained semiconductor package was post-cured at 175° C. for 4 hours to obtain a semiconductor device.

(MSL (Reflow resistance evaluation))
In each of Examples 1 to 14 and Comparative Examples 1 and 2, the obtained 12 semiconductor devices were left in an environment of 85° C. and a relative humidity of 60% for 168 hours, and then IR reflow treatment (260° C.) was performed. .. Next, the inside of the processed semiconductor device was observed with an ultrasonic flaw detector, and the area where peeling occurred at the interface between the sealing resin and the lead frame was calculated. For all semiconductor devices, the case where the peeled area is less than 5% is marked as ⊚, the case where the peeled area is 5% or more and 10% or less is marked as ◯, and the case where it exceeds 10% is marked as x.

(HTSL (High temperature storage characteristic evaluation))
For each of Examples 1 to 14 and Comparative Examples 1 and 2, the obtained semiconductor device was stored in an environment of 150° C., and the electrical resistance value between the electrode pad of the semiconductor chip and the bonding wire was measured every 24 hours. The measurement was performed, and the semiconductor device whose value increased by 20% from the initial value was determined to be defective. A sample in which no defect occurred even after 2000 hours of storage was rated as ⊚, a sample in which a defect occurred in 1000 to 2000 hours was rated as ◯, and a sample in which a defect occurred within 1000 hours was rated as x.

As shown in Table 1, in Examples 1 to 14, good results were obtained with respect to reflow resistance and high temperature storage characteristics. Examples 1-6,8,10,12-14 showed the more excellent high temperature storage characteristic compared with Examples 7,9,11. Further, Examples 2 to 14 showed further excellent reflow resistance as compared with Example 1.

100 semiconductor device 10 die attach material 20 semiconductor element 22 electrode pad 30 base material 32 die pad 34 outer lead 40 bonding wire 50 sealing resin

Claims (11)

A sealing resin composition used for sealing a semiconductor element and a bonding wire which is connected to the semiconductor element and which is made of a metal material having a Cu content of 99.9 mass% or more. There
Epoxy resin,
Hardener,
An ion scavenger,
A coupling agent,
A filler,
Including,
Does not contain aluminum hydroxide,
The coupling agent includes mercaptosilane,
The content of the coupling agent with respect to the entire solid content of the resin composition for sealing is 0.05% by mass or more and 0.5% by mass or less,
The content of the ion scavenger with respect to the entire solid content of the sealing resin composition is 0.05 mass% or more and 0.5 mass% or less,
The difference between the pH (1) measured under the following condition 1 and the pH (2) measured under the following condition 2 (pH(1)-pH(2)) is 0.1 or more and 1.1 or less. Which is a resin composition for sealing.
(Condition 1: A cured product obtained by thermally curing the encapsulating resin composition under the conditions of 175° C. for 4 hours is pulverized to obtain a pulverized product. Next, 5 g of the pulverized product immediately after pulverization is diluted with 50 ml of pure water. After putting in the water, the pure water is subjected to hot water extraction treatment at 125° C. for 20 hours, and the pH (pH(1)) of the obtained extract is measured)
(Condition 2: The encapsulating resin composition is thermally cured under the conditions of 175° C. for 4 hours to pulverize a cured product to obtain a pulverized product. Then, the pulverized product is stored at 175° C. for 500 hours. Next, 5 g of the crushed product after storage was put into 50 ml of pure water, and the pure water was subjected to hot water extraction treatment at 125° C. for 20 hours to obtain a pH ( pH (2)) is measured) The resin composition for sealing according to claim 1,
A resin composition for encapsulation having a pH (1) of 5 or more and 7 or less. The encapsulating resin composition according to claim 1 or 2 ,
A resin composition for encapsulation, wherein the ion scavenger contains at least one selected from hydrotalcites and polyvalent metal acid salts. The encapsulating resin composition according to any one of claims 1 to 3 ,
The said coupling agent is a resin composition for sealing which consists only of mercaptosilane. The encapsulating resin composition according to any one of claims 1 to 4 ,
A sealing resin composition in which the filler contains one or more selected from fused spherical silica, fused crushed silica, crystalline silica, talc, alumina, titanium white, and silicon nitride. The encapsulating resin composition according to any one of claims 1 to 5 ,
Content of the said filler with respect to the said whole resin composition for sealing is 35 mass% or more and 95 mass% or less, The resin composition for sealing. The resin composition for sealing according to any one of claims 1 to 6 ,
The epoxy resin is a sealing resin composition containing a naphthalene type epoxy resin. The encapsulating resin composition according to any one of claims 1 to 7 ,
Content of the said epoxy resin with respect to the said whole sealing resin composition is 1 mass% or more and 50 mass% or less, The resin composition for sealing. The encapsulating resin composition according to any one of claims 1 to 8 ,
A resin composition for encapsulation, wherein the curing agent contains a phenolic resin curing agent. The resin composition for sealing according to any one of claims 1 to 9 ,
Content of the said hardening|curing agent with respect to the said whole sealing resin composition is 2 mass% or more and 15 mass% or less. Semiconductor element,
A bonding wire which is connected to the semiconductor element and is made of a metal material having a Cu content of 99.9 mass% or more ;
A sealing resin which is composed of a cured product of the sealing resin composition according to any one of claims 1 to 10 , and which seals the semiconductor element and the bonding wire.
A semiconductor device comprising:

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