JP2000129098A - Epoxy resin composition for semiconductor and semiconductor device sealed therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain resin composition excellent in reflow resistance, reliability of humidity resistance, and ordinary temperature storage stability by selecting a composition essentially consisting of an epoxy resin, a curing agent, a cure accelerator, and an inorganic filler, wherein the epoxy resin contains one having a specified structure and the inorganic filler is used in a specified amount based on the entire weight. SOLUTION: This composition contains at least 20 wt.% epoxy resin having a structure represented by the formula (wherein G is glycidyl; R1 to R8 are each H, a halogen atom, or a 1-6C hydrocarbon group; and n is an integer of 0 or greater). The content of the inorganic filler is 84-95 wt.% based on the entire weight of the composition. It is desirable that the epoxy resin contains in addition to the epoxy resin of the formula, 20-80 wt.% based on the entire weight of the epoxy resin, dicyclopentadiene epoxy resin. It is also desirable that the curing agent contains an aralkyl resin in an amount of at least 20 wt.% based on the total amount of the curing agent and that the epoxy resin contains at least 20 wt.% dicyclopentadiene resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition for a semiconductor and a semiconductor device using the epoxy resin composition for a semiconductor. More specifically, the present invention is excellent in reflow resistance, humidity resistance and storage stability at room temperature. The present invention also relates to an epoxy resin composition for a semiconductor and a semiconductor device using the epoxy resin composition for a semiconductor.

[0002]

2. Description of the Related Art Heretofore, as a method for encapsulating electric and electronic parts such as diodes and transistor integrated circuits, semiconductor devices, and the like, for example, a method using an epoxy resin or a silicone resin, or a hermetic method using glass, metal, ceramic, or the like. A method such as a sealing method is employed.
In recent years, among them, resin sealing by low-pressure transfer using an epoxy resin, which is excellent in workability and mass productivity, has been becoming mainstream, in addition to improvement in reliability. In this sealing method using an epoxy resin, a molding material comprising an epoxy resin composition containing a cresol novolak type resin as an epoxy resin component and a phenol novolak type resin as a curing agent component has been most commonly used. Was.

[0003]

However, in such an epoxy resin composition for a semiconductor and a semiconductor device using the epoxy resin composition for a semiconductor, the I.S.
As electronic components such as C, LSI, and VLSI and semiconductor devices have become higher in density and more highly integrated, it has not always been possible to satisfy them satisfactorily.

Specifically, when a device for surface mounting is suddenly exposed to a severe and high temperature environment such as when the device itself is directly immersed in solder at the time of mounting, a package crack may occur. The situation was inevitable, and as a result, the reflow resistance was not good. In this case, when the moisture absorbed during storage after molding is exposed to a high temperature, the epoxy resin rapidly vaporized and expanded could not withstand the expansion and a package crack was generated.

[0005] Then, due to this package crack,
As a result, remarkable moisture resistance deterioration was caused, and as a result, long-term humidity resistance reliability could not be guaranteed. In addition, there was a difficulty in storage stability at room temperature, it was not possible to maintain a stable state for a long time, and remarkable deterioration was observed in moldability. Therefore, when left at room temperature for a long time during continuous molding or the like, the moldability of the material is reduced, which adversely affects the package itself.

[0006] The present invention has been made in view of the above-described facts, and has as its object the reflow resistance,
An object of the present invention is to provide an epoxy resin composition for semiconductors having excellent moisture resistance reliability and room temperature storage property, and a semiconductor device using the epoxy resin composition for semiconductors.

[0007]

An epoxy resin composition for a semiconductor according to claim 1 of the present invention comprises an epoxy resin, a curing agent, a curing accelerator, and an inorganic filler as essential components. In the above, as the epoxy resin, a resin having a structure represented by the following formula [I] is contained, and the inorganic filler is 84 to
It is characterized by containing 95 wt%.

[0008]

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According to a second aspect of the present invention, there is provided an epoxy resin composition for a semiconductor, wherein the epoxy resin having the structure represented by the formula (I) is 20 w
It is characterized by containing t% or more.

The epoxy resin composition for a semiconductor according to claim 3 of the present invention is characterized in that the epoxy resin is represented by the formula [I]:
In addition to the epoxy resin having the structure shown in the above, a dicyclopentadiene type epoxy resin is contained, and the dicyclopentadiene type epoxy resin contains 20 to 80 wt% based on the total amount of the epoxy resin. Features.

In the epoxy resin composition for a semiconductor according to a fourth aspect of the present invention, the curing agent contains an aralkyl resin, and the aralkyl resin contains at least 20 wt% based on the total amount of the curing agent. It is characterized by being.

The epoxy resin composition for a semiconductor according to claim 5 of the present invention, wherein the curing agent contains a dicyclopentadiene-type resin, and the dicyclopentadiene-type resin is added to the total amount of the curing agent. It is characterized by containing 20 wt% or more.

The epoxy resin composition for a semiconductor according to claim 6 of the present invention contains an ion trapping agent in addition to the above essential components.
It has a feature of having the structure shown in [I].

[0014]

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A semiconductor device according to a seventh aspect of the present invention is characterized in that it is sealed using the epoxy resin composition for a semiconductor according to any one of the first to sixth aspects.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments.

The epoxy resin composition for a semiconductor of the present invention comprises:
An epoxy resin, a curing agent, a curing accelerator, an epoxy resin composition for a semiconductor containing an inorganic filler as an essential component, wherein the epoxy resin contains a resin having a structure represented by the following formula (I), The inorganic filler,
It is contained in an amount of 84 to 95% by weight based on the total amount.

[0018]

Embedded image

As the epoxy resin, the above formula [I]
If it contains an epoxy resin having the structure shown in
Although there is no particular limitation even if any other type of epoxy resin is contained, generally, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, orthocresol novolac type epoxy resin , Phenol novolak type epoxy resin, alicyclic epoxy resin, triglycidyl isocyanurate, aliphatic epoxy resin, bromide-containing epoxy resin, dicyclopentadiene type epoxy resin, and the like, alone or in combination. is there. When a tablet is formed, it is easier to use a solid resin alone or in combination.

Further, the epoxy resin having the structure represented by the above formula [I] is 2% based on the total amount of the epoxy resin.
When the content is 0% by weight or more, since the epoxy resin is a low moisture absorbing resin, the epoxy resin composition to be obtained has a low moisture absorbing property, that is, a composition capable of sufficiently achieving moisture resistance reliability. Becomes Moreover, since the epoxy resin having the structure represented by the formula [I] is contained in the above-mentioned sufficient amount, the reflow resistance and the room temperature storage stability can be maintained more reliably.

It is assumed that the epoxy resin having the structure shown in the above formula [I] is 2% based on the total amount of the epoxy resin.
If the content is less than 0 wt%, this formula [I]
The amount of epoxy resin having the structure shown in the above is too small, and the resulting epoxy resin composition cannot sufficiently achieve low moisture absorption, and effectively maintains high reflow resistance and room temperature storage stability. Is not always possible.

The epoxy resin contains a dicyclopentadiene-type epoxy resin in addition to the epoxy resin having the structure represented by the above formula [I]. 20 to 80% by weight based on the amount of dicyclopentadiene-type epoxy resin, the reflow resistance, the moisture resistance reliability, and the room temperature storage stability can be more reliably improved with this amount. be able to.

If the dicyclopentadiene type epoxy resin is 20 wt.% Based on the total amount of the epoxy resin,
%, The amount of the dicyclopentadiene type epoxy resin is too small, and the resulting epoxy resin composition is not necessarily effective in reflow resistance,
This makes it difficult to obtain excellent moisture resistance reliability and room temperature storage stability. Conversely, the dicyclopentadiene-type epoxy resin is used in an amount of 8 to the total amount of the epoxy resin.
When the content exceeds 0 wt%, the amount of the dicyclopentadiene type epoxy resin is too large, the fluidity is deteriorated, and the amount of the epoxy resin having the structure represented by the above formula [I] is too small. And as a result,
The epoxy resin composition to be obtained cannot necessarily be effectively improved in reflow resistance, moisture resistance reliability and room temperature storage stability.

The curing agent is not particularly limited even if it contains any kind of curing agent. In general, phenol novolak, cresol novolak, phenol aralkyl, naphthol aralkyl, dicyclopentadiene type phenol is used. And various polyphenols such as triphenylmethane-type phenol.

In particular, when the curing agent contains an aralkyl resin, and the aralkyl resin contains at least 20 wt% based on the total amount of the curing agent, the amount of the aralkyl resin increases. It is possible to more reliably achieve excellent reflow resistance, moisture resistance reliability, and room temperature storage stability.

If the aralkyl resin contains less than 20% by weight based on the total amount of the curing agent, the aralkyl resin is too small and the resulting epoxy resin composition has low moisture absorption. Cannot be achieved sufficiently, and it is not always possible to effectively maintain high reflow resistance and room temperature storage stability.

Further, if the curing agent contains a dicyclopentadiene-type resin and the dicyclopentadiene-type resin contains at least 20 wt% based on the total amount of the curing agent, The dicyclopentadiene-type resin of the above can more reliably achieve excellent reflow resistance, moisture resistance reliability, and room temperature storage stability.

If the dicyclopentadiene-type resin contains less than 20% by weight based on the total amount of the curing agent, the amount of the dicyclopentadiene-type resin is too small and the resulting epoxy resin composition As a result, it is not possible to sufficiently achieve low moisture absorption,
It is not always possible to effectively maintain high reflow resistance and room temperature storage stability.

The curing accelerator is not particularly limited as long as it promotes the reaction between the epoxy resin, the curing agent, and the inorganic filler. Examples thereof include triphenylphosphine, Organic phosphines such as diphenylphosphine, 2-methylimidazole, 2-
Imidazoles such as phenyl-4-methylimidazole and 2-phenylimidazole; tertiary amines such as 1,8-diaza-bicyclo (5,4,0) undecene-7; triethanolamine and benzyldimethylamine; tetraphenyl A tetraphenylborate system such as phosphonium tetraphenylborate is used, and is used alone or in combination.

As described above, various inorganic fillers can be freely employed as long as they contain 84 to 95% by weight based on the total amount, and are not particularly limited. For example, fused silica, crystalline silica, alumina, silicon nitride and the like are used, and they are used alone or in combination. In general, fused silica is used in a proportion of 60 to 85% by weight in combination with other inorganic fillers. By containing the inorganic filler in an amount of 84 to 95 wt% based on the total amount, the obtained epoxy resin composition maintains characteristics such as moldability and maintains sufficiently high moisture resistance reliability. Can be done.

If the above-mentioned inorganic filler is used in an amount of 8
If the content is less than 4 wt%, the obtained epoxy resin composition cannot maintain sufficiently high moisture resistance reliability, and conversely, the above-mentioned inorganic filler is contained in the total amount. When the content exceeds 95 wt%, the obtained epoxy resin composition can maintain sufficiently high moisture resistance reliability,
The viscosity of the epoxy resin composition becomes excessively high, and accordingly, the moldability decreases, and finally the molding becomes impossible.

In addition to the above, if necessary, silane coupling agents such as γ-glycidoxypropyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane, carnauba wax, stearic acid and its derivatives, montanic acid and its It can contain a derivative, a release agent such as a carboxyl group-containing polyolefin, a discoloration inhibitor, an antioxidant, a pigment, a dye, a colorant, a modifier, a plasticizer, a diluent, and the like.

In the present invention, the mixture containing the essential components as described above is uniformly mixed with a mixer or a blender, and the mixture is heated and kneaded using a roll, a kneader or the like, cooled, and then cooled by a pulverizer. The desired epoxy resin composition for semiconductors can be prepared by pulverizing the powder into a tablet and pulverizing the powder into tablets.

According to the present invention, by adopting such a configuration,
An epoxy resin having excellent storage stability at room temperature and having a structure represented by the formula [I], which is a low moisture-absorbing resin, can sufficiently achieve low moisture absorption as the obtained epoxy resin composition. Viscosity can be maintained, and as a result, excellent reflow resistance and room temperature storage stability can be achieved while maintaining high moldability. In addition, the obtained epoxy resin composition maintains characteristics such as moldability, and particularly, the amount of the inorganic filler is 8 to the total amount.
When the content is 4 to 95 wt%, the moisture resistance reliability can be sufficiently maintained at a high level.

That is, according to the present invention, excellent reflow resistance, moisture resistance reliability, and room temperature storage stability can be obtained.

In addition, in addition to the above-mentioned essential components, an ion trapping agent is contained. If the ion trapping agent contains a substance having a structure represented by the following formula [II], the formula [II] The ion trapping agent having the structure shown in [II] can more surely and effectively have excellent reflow resistance, humidity resistance, and room temperature storage stability.

[0037]

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Further, the semiconductor device of the present invention is sealed by using any one of the above-mentioned epoxy resin compositions for semiconductors. Thus, by encapsulating the semiconductor epoxy resin composition by transfer molding or the like, it is possible to obtain a semiconductor device having excellent reflow resistance, moisture resistance reliability, and room temperature storage stability.

[0039]

Embodiments of the present invention will be described below in detail.

(Examples 1 to 6 and Comparative Examples 1 to 4) The components were uniformly mixed by a mixer at the compounding amounts shown in Table 1 below, heated and kneaded by a roll, cooled, and then pulverized by a pulverizer. ,
The epoxy resin composition for a semiconductor was prepared in each of Examples 1 to 6 and Comparative Examples 1 to 4 by tableting the powder into a tablet.

In addition, focusing on points other than those described in Table 1, triphenylphosphine (abbreviated as TPP; manufactured by Hokuko Chemical Co., Ltd.) is used as a curing accelerator, and wax is Carnauba wax was used, and as a coupling agent, a mercaptosilane-based coupling agent (manufactured by Toshiba Silicon Corporation, product number TSL8380) was used.
Further, as the flame retardant, diantimony trioxide (manufactured by Mitsubishi Materials Corporation, part number Sb2O3-NT) is used.
Carbon black (Mitsubishi Materials Corporation, part number 750
-B) was used.

With respect to the tablet of the epoxy resin composition for semiconductor prepared as described above, 15 mm × 19 mm ×
The reflow resistance and moisture resistance reliability were evaluated using a 2.4 mmt 60-pin QFP package.

First, the above-mentioned package was injected for 10 seconds, injection pressure was 70 kgf / cm ² , and pressing time was 90 seconds.
Seconds, after transfer molding under the condition of mold temperature 175 ° C,
Furthermore, after hardening was performed by a post-curing process at a temperature of 175 ° C. for 6 hours, the die pad surface was observed with an ultrasonic probe to check for peeling. Next, after subjecting the package to a moisture absorption treatment at 85 ° C. and 85% RH for 72 hours, the package is heated at a maximum temperature of 245 in a hot air reflow furnace.
A reflow treatment was performed at ℃. Then, after that, in the same package, the die pad surface is observed with an ultrasonic probe to check for peeling, the package is cut, the cross section is observed with a stereoscopic microscope, and the number of packages having cracks is determined. Each of the 10 samples was counted and evaluated.

Next, the moisture resistance reliability was measured by a pressure cooker test (PCT) at 133 ° C. and 100% RH using the package after the reflow resistance treatment.
And the number of occurrences of open failures (circuit disconnection failures) after 500 hours of processing time was counted and evaluated for each of 10 samples.

The room-temperature preservability is such that the epoxy resin compositions for semiconductor obtained in Examples 1 to 6 and Comparative Examples 1 to 4 are left at 25 ° C. and 60% RH for 72 hours. Was performed, and the deterioration rates of the spiral flow before and after the treatment were measured.

Table 1 below summarizes the results of the evaluation of the above-mentioned reflow resistance, moisture resistance reliability and room temperature storage stability.

[0047]

[Table 1]

Referring to the above and Table 1, the first embodiment
-6 and Comparative Examples 1-4, Examples 1-6
It can be seen that all of the above are far superior to those of Comparative Examples 1 to 4 in all the evaluation items of the reflow resistance, the moisture resistance reliability, and the room temperature storage stability.

From the above, it can be seen that an epoxy resin composition having excellent storage stability at room temperature and having a structure represented by the formula [I], which is a low moisture absorbing resin, has sufficient low moisture absorption properties. It can be said that the viscosity can be kept low, and as a result, excellent reflow resistance and room temperature storage property can be obtained while maintaining high moldability. In addition, as the obtained epoxy resin composition, while maintaining properties such as moldability, particularly, the inorganic filler is 84 to 95 wt.
%, It can be said that the moisture resistance reliability can be maintained sufficiently high.

That is, the present invention can be said to be excellent in reflow resistance, moisture resistance reliability, and room temperature storage stability.

[0051]

The epoxy resin composition for semiconductors according to claim 1 of the present invention is obtained by using an epoxy resin having excellent storage stability at room temperature and having a structure represented by the formula [I] which is a low moisture absorbing resin. The resulting epoxy resin composition can sufficiently reduce moisture absorption and maintain low viscosity. As a result, while maintaining high moldability, it has excellent reflow resistance and room temperature storage stability. It is something that can be. In addition, the obtained epoxy resin composition maintains properties such as moldability, and particularly contains 84 to 95 wt% of the inorganic filler with respect to the total amount.
It is possible to sufficiently maintain the high humidity resistance reliability.

That is, the present invention can provide excellent reflow resistance, moisture resistance reliability, and room temperature storage stability.

The epoxy resin composition for a semiconductor according to the second to sixth aspects of the present invention should be more reliably and effectively excellent in reflow resistance, humidity resistance and room temperature storage stability. Can be.

The semiconductor device according to claim 7 of the present invention can provide a semiconductor device having excellent reflow resistance, moisture resistance reliability, and room temperature storage stability.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masayuki Kyogaku 1048 Kazuma Kadoma, Kadoma-shi, Osaka F-term in Matsushita Electric Works, Ltd. 4J036 AA05 AB17 AD08 AD20 AD21 AE07 AF06 AF08 AJ08 DB06 DC12 DC41 DC46 DD07 FA01 FA04 FA05 FB06 FB07 GA04 JA07 4M109 AA01 BA01 CA21 EA02 EA06 EB02 EB04 EB06 EB07 EB08 EB09 EB12 EB18 EC03 EC05 EC14

Claims (7)

[Claims] 1. An epoxy resin composition for a semiconductor containing an epoxy resin, a curing agent, a curing accelerator, and an inorganic filler as essential components, wherein the epoxy resin has a structure represented by the following formula [I]: An epoxy resin composition for a semiconductor, wherein the composition further comprises 84 to 95 wt% of the inorganic filler based on the total amount. Embedded image 2. An epoxy resin having a structure represented by the above formula [I] is used in an amount of 20 w
The epoxy resin composition for a semiconductor according to claim 1, wherein the content is at least t%. 3. The epoxy resin of the formula [I]
In addition to the epoxy resin having the structure shown in the above, a dicyclopentadiene type epoxy resin is contained, and the dicyclopentadiene type epoxy resin contains 20 to 80 wt% based on the total amount of the epoxy resin. The epoxy resin composition for a semiconductor according to claim 1 or 2, wherein 4. The method according to claim 1, wherein the curing agent contains an aralkyl resin, and the aralkyl resin contains at least 20 wt% based on the total amount of the curing agent. Or the epoxy resin composition for a semiconductor according to the above. 5. The method according to claim 1, wherein the curing agent contains a dicyclopentadiene-type resin, and the dicyclopentadiene-type resin contains at least 20 wt% of the total amount of the curing agent. The epoxy resin composition for a semiconductor according to any one of claims 1 to 4. 6. An ion trapping agent is contained in addition to the above essential components.
The epoxy resin composition for a semiconductor according to any one of claims 1 to 5, wherein the composition has a structure shown in (I). Embedded image 7. A semiconductor device which is encapsulated with the epoxy resin composition for a semiconductor according to claim 1.