JP2851699B2 - Semiconductor device and epoxy resin composition for semiconductor encapsulation used therein - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device having excellent reliability and an epoxy resin composition for semiconductor encapsulation used therein.

[Conventional technology]

Conventionally, semiconductor devices such as transistors, ICs, and LSIs have been encapsulated with ceramic packages and the like to form semiconductor devices, but recently, from the viewpoint of cost and mass productivity,
Resin sealing using a plastic package has become mainstream. Epoxy resins have conventionally been used for this type of resin sealing, and have achieved good results. However, due to technological innovation in the field of semiconductors, the degree of integration has been improved, the element size has been increased, and the wiring has become finer, and the packages have also become smaller and thinner. On the other hand, higher reliability (reduction of thermal stress of the obtained semiconductor device, reliability of moisture resistance, reliability against thermal shock test, etc.) is required. In particular, in recent years, the size of semiconductor devices has been increasing in size, and there is a demand for further improvement in performance over a thermal cycle test (TCT test), which is an accelerated test for evaluating the performance of a semiconductor sealing resin.
In addition, surface mounting has become the mainstream mounting method for semiconductor packages, and for this reason, even if the semiconductor package is absorbed and then immersed in a molten solder, cracks and blisters do not occur in the package. Have been.

In this regard, it has been studied to modify the epoxy resin with a silicone compound to reduce thermal stress in order to improve the properties evaluated in the TCT test, and to improve the crack resistance during solder immersion. For this reason, studies have been made to improve the adhesion to the lead frame, but the effect is still insufficient.

[Problems to be solved by the invention. ]

As described above, the epoxy resin compositions for sealing up to now have not been satisfactory in the results of the TCT test and in the properties of crack resistance during solder immersion. For this reason, it is strongly desired to improve both of the above characteristics so as to be able to cope with the increase in the size of the semiconductor element and the surface mounting due to the above technical innovation.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a semiconductor device having improved characteristics evaluated by a TCT test and excellent crack resistance during immersion in a solder melt, and an epoxy resin composition for semiconductor encapsulation used in the semiconductor device.

[Means for solving the problem]

In order to achieve the above object, the present invention provides the following (A)
A first aspect is a semiconductor device in which a semiconductor element is sealed using an epoxy resin composition containing the components (C) to (C). (A) At least one of the following (A) and (B).

(A) An epoxy resin containing one or more bridged hydrocarbon compound groups in one molecule and comprising a glycidyl etherified product of a bridged hydrocarbon compound-modified phenol resin represented by the following general formula (I).

[In the formula (I), R is a bridged hydrocarbon compound group, and n is an integer of 0 to 300. (B) Epoxy resins other than the above (a).

(B) at least one of the following (c) and (d) [provided that the component (A) comprises only the above (b)
The component (B) comprises at least (c)].

(C) A bridged hydrocarbon compound-modified phenol resin containing one or more bridged hydrocarbon compound groups in one molecule and represented by the following general formula (II).

[In the formula (II), R is a bridged hydrocarbon compound group, and n is an integer of 0 to 300. (D) A phenolic resin other than the above (c).

(C) an inorganic filler.

In addition to the above components (A) to (C), the following general formula (II)
A second subject is a semiconductor device in which a semiconductor element is sealed using an epoxy resin composition containing at least one of the silicone compound represented by I) and the silicone compound represented by the general formula (IV).

[In the formulas (III) and (IV), R is a methyl group, R ₁
Is CH _{2 l} (where 1 is an integer of 1 to 3), A is an amino group, an epoxy group, a carboxyl group, a hydroxyl group or a cyclohexene oxide group, m is an integer of 1 to 300, and n is an integer of 0 or 1 to 300 ( Where m + n = 1 to 500)
x is an integer of 10 to 300. [Action] The present inventors have conducted a series of studies in order to improve the properties evaluated in the TCT test and to improve the crack resistance when immersed in a solder melt. As a result, when an epoxy resin and a phenol resin having a special skeleton structure represented by the above general formulas (I) and (II) are used, these special resins and the above general formulas (III) and (IV) can be further used. The present inventors have found that the combined use of the special silicone compound represented by the formula shows both excellent TCT test and crack resistance when immersed in a solder melt after moisture absorption.

 Next, the present invention will be described in detail.

The epoxy resin composition used in the semiconductor device of the present invention has the following four modes depending on the combination of the epoxy resin constituting the component A and the phenol resin constituting the component B.

The first embodiment is a novel epoxy resin <general formula (I)>
And a normal phenolic resin.
Is a combination of an ordinary epoxy resin and a novel phenolic resin <general formula (II)>, and a third aspect is:
A fourth embodiment is a combination of the novel epoxy resin and the novel phenol resin, and a fourth embodiment is a combination of one or both of the novel epoxy resin and the novel phenol resin with a regular epoxy resin or a regular phenol resin. In addition, these four types include the above-mentioned general formula (II)
Combinations of the special silicone compounds represented by I) and (IV) are also included. These are usually in the form of a powder or a tablet obtained by compressing them.

 First, the first embodiment will be described.

The novel epoxy resin constituting the component A used in the first embodiment is represented by the general formula (I), and is a modified phenol having a bridged hydrocarbon compound containing one or more bridged hydrocarbon compound groups in one molecule. It is a glycidyl etherified resin. The above-mentioned bridged hydrocarbon compound variable phenol resin is produced by, for example, copolymerizing a bridged hydrocarbon diene compound such as phenol and dicyclopentadiene with an acidic catalyst. In this way, a bridged hydrocarbon compound-modified phenol resin containing one or more bridged hydrocarbon compounds is produced. Examples of the bridged hydrocarbon compound group include a bicyclo (2,2,1) heptane group and a bicyclo (3,2,1)
Bicyclic bridging compound groups such as octane groups and tricyclo (5,
2,1,0 ^2,6 ) tricyclic crosslinking compound groups such as decane groups. And it is obtained by glycidyl etherification. In the above reaction, the degree of condensation is preferably from 4 to 6.

The ordinary phenol resin used together with the above-mentioned novel epoxy resin is not particularly limited, and a conventionally known one can be used. For example, phenol novolak, cresol novolak, and the like are preferably mentioned. It is preferable to use those novolak resins having a softening point of 50 to 110 ° C. and a hydroxyl equivalent of 70 to 150. Particularly, the use of cresol novolak among the above novolak resins gives good results.

The mixing ratio of the novel epoxy resin and the ordinary phenol resin is preferably such that the hydroxyl group in the phenol resin is 0.8 to 1.2 equivalent per 1 equivalent of the epoxy group in the epoxy resin.

The inorganic filler of the C component used together with the above-mentioned novel epoxy resin and ordinary phenol resin is not particularly limited, and generally used quartz glass powder, talc, silica powder, alumina powder, calcium carbonate, carbon black powder And the like. In particular, it is preferable to use silica powder. In the case of silica powder, the content of such an inorganic filler is 50% of the entire epoxy resin composition.
% Is preferable. It is particularly preferably at least 80%. That is, when the content of the silica powder is less than 50%, the effect of containing the filler tends to be significantly reduced.

 Next, the second embodiment will be described.

The ordinary epoxy resin used in the second embodiment is:
There is no particular limitation, and a conventionally known one is used. For example, bisphenol A type, phenol novolak type, cresol novolak type and the like can be mentioned. Among these resins, the melting point exceeds room temperature, and those exhibiting a solid or high-viscosity solution at room temperature give good results. As the phenol novolak type epoxy resin, those having an epoxy equivalent of 160 to 260 and a softening point of 50 to 130 ° C. are usually used.As the cresol novolak type epoxy resin, an epoxy equivalent of 180 to 210 and a softening point of 60 to 110 are used. ° C is commonly used.

The novel phenol resin used together with the above-mentioned ordinary epoxy resin is represented by the general formula (II), and has a skeleton of a bridged hydrocarbon compound-modified phenol resin containing one or more bridged hydrocarbon compound groups in one molecule. And the degree of condensation is preferably from 4 to 6. Such a novel phenol resin is obtained in the same manner as in the preparation of the phenol resin before glycidyl etherification of the novel epoxy resin used in the first embodiment.

The compounding ratio of the ordinary epoxy resin and the new phenol resin is also the same as in the first embodiment, so that the hydroxyl group in the novel phenol resin is 0.8 to 1.2 equivalent per 1 equivalent of the epoxy group in the ordinary epoxy resin. It is preferable to mix them.

The inorganic filler used together with the above-mentioned ordinary epoxy resin and novel phenol resin may be the same as in the first embodiment, and the amount thereof is preferably set to the same ratio.

 Next, the third embodiment will be described.

The third embodiment is a combination of a novel epoxy resin and a novel phenol resin.
And the second embodiment are the same as those used in the second embodiment.

 Further, the fourth aspect will be described.

The fourth embodiment is a combination of one or both of the novel epoxy resin and the novel phenol resin with a usual epoxy resin or a usual phenol resin. In this case, the mixing ratio of the ordinary epoxy resin or phenol resin is preferably set to less than 50% by weight (hereinafter abbreviated as “%”) of the entire epoxy resin component or the entire phenol resin component, respectively.

Examples of the inorganic filler used together with the epoxy resin component and the phenol resin component include the same ones as those used in the first to third embodiments.

Further, a special silicone compound may be used in addition to the epoxy resin component, the phenol resin component and the inorganic filler used in the first to fourth embodiments.
Examples of the special silicone compound include those represented by the following general formulas (III) and (IV), which are used alone or in combination.

[In the formulas (III) and (IV), R is a methyl group, R ₁
Is CH _{2 l} (where 1 is an integer of 1 to 3), A is an amino group, an epoxy group, a carboxyl group, a hydroxyl group or a cyclohexene oxide group, m is an integer of 1 to 300, and n is an integer of 0 or 1 to 300 ( Where m + n = 1 to 500)
x is an integer of 10 to 300. The amount of such a silicone compound is preferably set so that the amount of the silicone compound is 5% or less of the entire epoxy resin composition. Particularly preferred is 0.5-3.0
%. That is, when the compounding amount of the silicone compound exceeds 5%, characteristics such as heat resistance tend to decrease.

In addition to the epoxy resin component, phenol resin component, inorganic filler, and silicone compound used in the first to fourth embodiments, the epoxy resin composition used in the present invention may further include a curing accelerator, if necessary. Conventionally known tertiary amines, quaternary ammonium salts, imidazoles and boron compounds can be used alone or in combination. In addition, antimony trioxide, phosphorous compounds and other fuels, carbon black and pigments such as titanium oxide,
A release agent such as paraffin or an aliphatic ester, or a coupling agent such as a silane coupling agent can be used.

The epoxy resin composition used in the present invention can be produced, for example, as follows. That is, the epoxy resin, the phenol resin, and the inorganic filler used in the first to fourth embodiments, a silicone compound in addition to these, and a curing accelerator, a flame retardant if necessary,
A pigment, a release agent and a silane coupling agent are blended in a predetermined ratio. Then, the mixture is melt-kneaded in a heated state using a kneader such as a mixing roll machine, cooled to room temperature, pulverized by a known means, and tableted as necessary. The desired epoxy resin composition can be obtained by the step (1).

The method of sealing a semiconductor element using such an epoxy resin composition is not particularly limited, and it can be performed by a known molding method such as ordinary transfer molding.

〔The invention's effect〕

As described above, the semiconductor device of the present invention uses a special epoxy resin composition containing at least one of a novel epoxy resin containing a bridged hydrocarbon compound group and a novel phenol resin containing a bridged hydrocarbon compound group. Due to the sealing, the characteristics evaluated in the TCT test are improved and the life is extended. In addition, even when immersed in a solder melt after absorbing moisture, package cracks are unlikely to occur. Further, when a special silicone compound [the above general formulas (III) and (IV)] is used in combination with the epoxy resin composition, the effect can be further improved. As a result, 8 pins or more can be obtained by sealing with the above-mentioned special and epoxy resin composition.
Particularly, in a large semiconductor device having 16 pins or more or a semiconductor element having a long side of 4 mm or more, the above-described high reliability can be obtained, which is a great feature.

 Next, examples will be described together with comparative examples.

Prior to preparation of the epoxy resin composition, silicone compounds shown in Table 1 below were prepared.

[Examples 1 to 27, Comparative Examples 1 to 3] The silicone compounds shown in the above Table 1 and the respective raw materials shown in the following Table 2 were blended in the proportions shown in the same table, and mixed on a mixing roll machine (temperature 100 ° C). ) And melt kneading for 3 minutes,
After cooling and solidification, the mixture was pulverized to obtain a desired powdery epoxy resin composition.

Using the epoxy resin compositions obtained in the above Examples and Comparative Examples, a semiconductor device is obtained by transfer molding a semiconductor element (condition: 175 ° C. × 2 minutes, 175 ° C. × 5 hours post-curing). Was. This package is an 80-pin four-way flat package (80-pin QFP, size: 20 × 14 × 2 mm), and the die package size is 8 × 8 mm.

The semiconductor device obtained in this manner was subjected to −50 ° C.
A TCT test was performed at / 5 minutes to 150 ° C / 5 minutes. 85 ℃ / 85
After leaving it in a constant temperature bath at a relative humidity of% RBH to absorb moisture, a test was conducted in which it was immersed in a 260 ° C. solder melt for 10 seconds. The results are shown in Table 3 below.

From the results shown in Table 3, it is clear that the example product has significantly better crack resistance when immersed in the TCT test and the solder melt than the conventional product of the comparative example.

Continuation of front page (56) References JP-A-3-177416 (JP, A) JP-A-3-179019 (JP, A) JP-A-4-183711 (JP, A) JP-A-3-195722 (JP) JP-A-3-210322 (JP, A) JP-A-4-153213 (JP, A) JP-A-3-220228 (JP, A) JP-A-3-243615 (JP, A) 3-263423 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) H01L 23/28-23/30 C08G 59/24 C08G 59/62

Claims (6)

(57) [Claims] 1. A semiconductor device comprising a semiconductor element encapsulated with an epoxy resin composition containing the following components (A) to (C). (A) At least one of the following (A) and (B). (A) An epoxy resin containing one or more bridged hydrocarbon compound groups in one molecule and comprising a glycidyl etherified product of a bridged hydrocarbon compound-modified phenol resin represented by the following general formula (I). [In the formula (I), R is a bridged hydrocarbon compound group, and n is an integer of 0 to 300. (B) Epoxy resins other than the above (a). (B) at least one of the following (c) and (d) [provided that the component (A) comprises only the above (b)
The component (B) comprises at least (c)]. (C) A bridged hydrocarbon compound-modified phenol resin containing one or more bridged hydrocarbon compound groups in one molecule and represented by the following general formula (II). [In the formula (II), R is a bridged hydrocarbon compound group, and n is an integer of 0 to 300. (D) A phenolic resin other than the above (c). (C) an inorganic filler. 2. A silicone compound represented by the following general formula (III) and a silicone compound represented by the following general formula (IV) in addition to the components (A) to (C) described in claim (1). A semiconductor device in which a semiconductor element is sealed using an epoxy resin composition containing at least one. [In the formulas (III) and (IV), R is a methyl group, R ₁
Is CH _{2 l} (where 1 is an integer of 1 to 3), A is an amino group, an epoxy group, a carboxyl group, a hydroxyl group or a cyclohexene oxide group, m is an integer of 1 to 300, and n is an integer of 0 or 1 to 300 ( Where m + n = 1 to 500)
x is an integer of 10 to 300. ] 3. The semiconductor device according to claim 1, wherein a semiconductor element having eight or more pins is sealed. 4. The semiconductor device according to claim 1, wherein a semiconductor element having 16 pins or more is sealed. 5. The semiconductor device according to claim 1, wherein a semiconductor element having a long side of 4 mm or more is sealed. 6. An epoxy resin composition for semiconductor encapsulation comprising the following components (A) to (C): (A) At least one of the following (A) and (B). (A) An epoxy resin containing one or more bridged hydrocarbon compound groups in one molecule and comprising a glycidyl etherified product of a bridged hydrocarbon compound-modified phenol resin represented by the following general formula (I). [In the formula (I), R is a bridged hydrocarbon compound group, and n is an integer of 0 to 300. (B) Epoxy resins other than the above (a). (B) at least one of the following (c) and (d) [provided that the component (A) comprises only the above (b)
The component (B) comprises at least (c)]. (C) A bridged hydrocarbon compound-modified phenol resin containing one or more bridged hydrocarbon compound groups in one molecule and represented by the following general formula (II). [In the formula (II), R is a bridged hydrocarbon compound group, and n is an integer of 0 to 300. (D) A phenolic resin other than the above (c). (C) an inorganic filler.