JPH06207082A - Resin composition for semiconductor sealing and semiconductor device sealed therewith - Google Patents

Abstract

PURPOSE:To obtain a resin composition for semiconductor sealing excellent in mold release, stampability and humidity resistance by mixing an epoxy resin with a curing agent and a specified fluorinated higher fatty acid ester. CONSTITUTION:100 pts.wt. total of an epoxy, resin of a total chlorine content of 500ppm or below and a curing agent in an amount to give a ratio of the number of equivalents of the epoxy groups of the epoxy resin to the number of equivalents of the OH groups of the curing agent of 0.5-2.0 is mixed with 0.01-10 pts.wt. fluorinated higher fatty acid ester of formula I (wherein R is a group of formula II or III; p is 4-16; r is 4-60; and q is 1-5) and 100-1000 pts.wt. inorganic filler of a mean particle diameter of 3-15mum, and the resulting mixture is kneaded at 70-95 deg.C to obtain the objective composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a semiconductor which can provide a cured product having excellent reliability such as moisture resistance, has good releasability at the time of molding, and has good imprintability on a molded product. The present invention relates to a resin composition for encapsulation and a semiconductor device encapsulated with the composition.

[0002]

2. Description of the Related Art Currently,
In the semiconductor industry, resin-sealed diodes, transistors, ICs, LSIs, VLSIs are the mainstream,
Above all, the epoxy resin, the curing agent, and the epoxy resin composition containing various additives are generally superior to other thermosetting resins in moldability, adhesiveness, electrical properties, mechanical properties, moisture resistance, etc. Therefore, a semiconductor device is often sealed with an epoxy resin composition. However, in recent years, the integration degree of these semiconductor devices has become larger and larger, and the chip size has been increasing accordingly. On the other hand, the external dimensions of the package are becoming smaller and thinner along with the demand for smaller and lighter electronic devices. Further, also in the method of mounting the semiconductor component on the circuit board, the surface mounting of the semiconductor component has been often performed in order to increase the density of the component on the board.

However, when the semiconductor device is surface-mounted, it is common to immerse the entire semiconductor device in a solder bath or pass through a high temperature zone where the solder melts. A crack may occur in the layer, or peeling may occur at the interface between the lead frame or chip and the sealing resin. Such cracks and peeling become more noticeable if the sealing resin layer of the semiconductor device absorbs moisture before the thermal shock during surface mounting, but in the actual working process, the moisture absorption of the sealing resin layer Inevitably, the reliability of the semiconductor device sealed with the epoxy resin after mounting may be greatly impaired. Therefore, it is desirable to further improve the reliability of the sealing resin.

In order to solve such a problem, an epoxy resin having a naphthalene skeleton or a biphenyl skeleton has characteristics of low water absorption and toughness in place of the conventionally used orthocresol novolac type epoxy resin. Therefore, it has been attracting attention (Japanese Patent Application Laid-Open No. 61-
47725, JP-A-4-21142).

However, when the epoxy resin having the above-mentioned skeleton is used, there is a problem that the releasability at the time of molding is insufficient, and there is also a problem with the imprintability. For this reason, it has been customary to mix an internal release agent such as an ester wax of a long chain fatty acid such as carnauba wax and a bisamide wax such as ethylenebisstearic acid amide. None of the release agents satisfied the characteristics such as reliability such as moisture resistance, releasability and imprintability.

The present invention has been made in view of the above circumstances.
An object of the present invention is to provide a resin composition for semiconductor encapsulation and a semiconductor device which provide a cured product having excellent releasability at the time of molding and imprintability on a molded product and excellent moisture resistance.

[0007]

Means and Actions for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that a resin composition containing an epoxy resin and a curing agent has the following general formula as an internal release agent. By blending the fluorine atom-containing higher fatty acid ester represented by (1), even when an epoxy resin having a naphthalene ring skeleton or a biphenyl skeleton is used as the epoxy resin, excellent releasability at the time of molding, and a molded product It was found that a resin composition that gives a cured product having excellent imprintability and excellent moisture resistance can be obtained, and the present invention has been completed.

Therefore, the present invention provides a resin composition for semiconductor encapsulation containing (A) epoxy resin and (B) curing agent,
(C) The following general formula (1)

[0009]

[Chemical 3] The present invention provides a resin composition for semiconductor encapsulation, comprising a fluorine atom-containing higher fatty acid ester represented by and a semiconductor device encapsulated with a cured product of the composition.

The present invention will be described in more detail below. In the resin composition for semiconductor encapsulation of the present invention, the epoxy resin as the component (A) is a novolac type epoxy resin, a biphenol A type epoxy resin or a triphenol alkane type epoxy resin. Examples thereof include an epoxy resin, a naphthalene ring-containing epoxy resin represented by the following general formula (2), and a biphenyl type epoxy resin represented by the following general formula (3).

[0011]

[Chemical 4]

Examples of the naphthalene ring-containing epoxy resin of the above formula (2) include the following.

[0013]

[Chemical 5]

[0014]

[Chemical 6]

Examples of the biphenyl type epoxy resin of the formula (3) are shown below.

[0016]

[Chemical 7]

In these biphenyl group-containing epoxy resins, considering that the epoxy resin composition is maintained at a low viscosity and the total chlorine content in the epoxy resin composition is 500 ppm or less, the above formula (4) The compound shown by these is preferable.

Next, examples of the curing agent which is the component (B) of the present invention include phenol type curing agents, amine type curing agents, and acid anhydride type curing agents. Particularly, phenol type curing agents should be used. Is preferred. The phenol-based curing agent is not particularly limited, but preferably phenol novolac resin, triphenol alkane type resin,
Examples thereof include phenylaralkyl resin and naphthalene-containing resin. Specifically, the following compounds may be mentioned.

[0019]

[Chemical 8]

[0020]

[Chemical 9] (However, in the above formula, R ⁴ represents a hydrogen atom, a halogen or an alkyl group having 1 to 5 carbon atoms, and g represents an integer of 0 to 5.)

The blending amount of the curing agent as the component (B) is appropriately selected according to the type of the curing agent, and the ratio of the epoxy equivalent of the epoxy resin to the OH equivalent of the curing agent is 0.5 to 2.0. It is preferable.

Next, the fluorine atom-containing higher fatty acid ester which is the component (C) constituting the resin composition of the present invention is represented by the following formula (1), and is used as an internal mold release agent at the time of molding. Is.

[0023]

[Chemical 10]

Specific examples of the compound represented by the above formula (1) include those shown below.

[0025]

[Chemical 11]

Here, the addition amount of the component (C) is
It is preferable to add 0.01 to 10 parts, especially 0.1 to 5 parts to 100 parts (parts by weight, the same applies hereinafter) of the total amount of the components (A) and (B). When the addition amount is less than 0.01 part, the effect of improving the releasability is not sufficient, and when it exceeds 10 parts, problems such as a decrease in mechanical strength may occur. Further, the component (C) according to the present invention may be used in combination with other releasing agents such as carnauba wax.

In the present invention, it is preferable to add an inorganic filler, if necessary, in addition to the above components, from the viewpoint of reducing the expansion coefficient and water absorption. As the inorganic filler, those which are usually blended with the epoxy resin composition can be used. Specifically, fused silica, silicas such as crystalline silica, alumina, silicon nitride, aluminum nitride,
Examples thereof include boron nitride, titanium oxide, glass fiber and the like. Of these, fused silica is particularly desirable, and one having an average particle size of 3 to 15 microns is desirable from the viewpoint of moldability. It should be noted that the inorganic filler is preferably blended with a surface-treated in advance with a silane coupling agent or the like in order to increase the bonding strength between the resin and the surface of the inorganic filler.

These inorganic fillers may be used alone or in combination of two or more, and the compounding amount is not particularly limited, but the total amount of the components (A) and (B) is 1
100 to 1000 parts, especially 200 to 700 parts per 00 parts
It is preferably within the range of parts.

Further, a curing catalyst can be added to the resin composition for semiconductor encapsulation of the present invention, and examples of the curing catalyst include imidazole compounds, tertiary amine compounds and phosphorus compounds. The blending amount thereof is not particularly limited, but it is preferably 0.1 to 2 parts, particularly 0.4 to 1.5 parts based on 100 parts of the total amount of the components (A) and (B).

The composition of the present invention may further contain various additives, if desired, such as thermoplastic resins, thermoplastic elastomers, organic synthetic rubbers, low stress agents such as silicones, stearic acid. Such as fatty acids and their metal salts, pigments such as carbon black, cobalt blue, red iron oxide, antimony oxide, flame retardants such as halogen compounds,
Silane coupling agents such as glycidoxypropyltrimethoxysilane, surface treatment agents such as alkyl titanates,
Additives such as an anti-aging agent and a halogen trap agent can be added.

Here, in the resin composition of the present invention, a predetermined amount of the above-mentioned portion is uniformly stirred and mixed in the production thereof,
It can be obtained by a method such as kneading with a kneader, roll, extruder or the like which has been heated to 70 to 95 ° C. in advance, cooling and pulverizing. There is no particular limitation on the order of mixing the components.

The thus obtained resin composition for semiconductor encapsulation of the present invention contains SOP, SOJ, TSOP and TQF.
It can be effectively used for encapsulating a semiconductor device such as P. In this case, molding can be performed by adopting a conventionally used molding method such as transfer molding, injection molding, or casting method. At this time, the molding temperature is preferably 150 to 180 ° C. for 30 to 180 seconds, and the post cure is preferably 150 to 180 ° C. for 2 to 16 hours.

[0033]

EFFECT OF THE INVENTION The resin composition for semiconductor encapsulation of the present invention provides a cured product having excellent moisture resistance, and has excellent mold releasability during molding and imprintability on a molded product, and is useful for semiconductor encapsulation. The semiconductor device encapsulated with the cured product of this composition has high reliability.

[0034]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following examples, all parts are parts by weight.

[Examples 1 to 10 and Comparative Examples 1 to 4] Epoxy resins, phenol resins and mold release agents were added in the compositions shown in Tables 1 and 2, and 0.6 parts of a curing catalyst shown below was further added thereto
0.7 parts triphenylphosphine, 600 parts fused spherical silica having an average particle size of 15 microns, 100 parts fused spherical silica having an average particle size of 1 micron, 8 parts antimony trioxide, 1.5 parts carbon black and γ-glycidoxy The composition obtained by adding 1.5 parts of propyltrimethoxysilane was mixed and kneaded with a hot roll at 90 ° C. for 3 minutes to obtain an epoxy resin composition. Curing catalyst 1,8-diazabicyclo (5.4.0) undecene-7
And phenol novolac resin (TD2131, manufactured by Dainippon Ink and Chemicals) in a ratio of 20/80 (weight ratio),
After heat-melting and mixing these at 130 ° C. for 30 minutes, 50
Grinded to micron or less.

Next, using the compositions obtained in Examples and Comparative Examples, 80 pin QFP (14 × 20 × 2.7 m)
m) with a transfer molding machine at a pressure of 70 kg / cm
² , mold the molded product under the condition that the mold temperature is 175 ℃, 2 minutes,
Further, post-curing was performed at 180 ° C. for 4 hours, and the following various characteristics (a) to (e) were measured. The results are also shown in Tables 1 and 2. (B) Releasing property Immediately after opening the mold, the mold spool was pushed with a push-pull gauge to measure the force when the mold was released. (B) Imprintability The surface of the obtained IC-encapsulated product was imprinted with silver ink (Bonmark C manufactured by Baba Inbo), ink-cured at 150 ° C for 1 hour, and then peeled off with a cellophane tape, even if a little. If there was a missing character, it was judged as bad. (C) Reliability A pressure cooker test (PCT: 121 ° C. steam, 2 atm) was performed on the obtained IC-sealed product to examine the corrosion of the aluminum wiring. The occurrence of open due to aluminum corrosion was detected and expressed as the time of initial failure occurrence. (D) Solder crack resistance after moisture absorption The obtained IC-sealed product was exposed to an atmosphere of 85 ° C / 85% RH for 1
After standing for 68 hours, perform 215 ° C VPS for 30 seconds,
The number of package cracks was measured. (E) Water absorption rate Molding conditions: 175 ° C., 70 kg / cm ² , molding time: 2 minutes, post-curing at 180 ° C. for 4 hours Diameter 50
A disc having a thickness of 2 mm and a thickness of 2 mm was left in an atmosphere of 121 ° C./100% RH for 24 hours to measure the water absorption. The results are shown in Tables 1 and 2.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

[Chemical 12]

[0040]

[Chemical 13]

[0041]

[Chemical 14]

From the results shown in Tables 1 and 2, the epoxy resin composition containing the mold releasing agent of the present invention (Example) has releasability as compared with those containing other mold releasing agents (Comparative Example). It was confirmed that the marking property, the reliability, and the solder crack resistance after moisture absorption were excellent.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayuki Aoki 1 Hitomi, Otomi, Matsuida-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory

Claims (3)

[Claims] 1. A resin composition for semiconductor encapsulation containing (A) an epoxy resin and (B) a curing agent, wherein (C) the following general formula (1): A resin composition for semiconductor encapsulation, comprising a fluorine atom-containing higher fatty acid ester represented by 2. The naphthalene ring-containing epoxy resin represented by the following general formula (2) or the biphenyl type epoxy resin represented by the following general formula (3) is used as the component (A) epoxy resin. Composition. [Chemical 2] 3. A semiconductor device encapsulated with the cured product of the composition according to claim 1.