JP2872973B2 - Semiconductor device and epoxy resin composition for semiconductor encapsulation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a semiconductor device having excellent reliability even in a high-temperature atmosphere.
The present invention relates to an epoxy resin composition for stopping .

[0002]

2. Description of the Related Art Semiconductor devices such as transistors, ICs, and LSIs are generally sealed with an epoxy resin composition to form semiconductor devices. The epoxy resin has been used for encapsulation of a semiconductor device because of its good electrical properties, moisture resistance, adhesiveness and the like, and has achieved good results.
However, in recent years, as semiconductor devices are used in large quantities in many outdoor devices such as automobiles, heat resistance more than ever, especially high-temperature storage reliability which has not been a problem in the past, has been increasing. Of semiconductor devices.

[0003]

Conventionally, such heat resistance is improved by increasing the flame retardancy of an epoxy resin used for sealing. That is, by combining the brominated epoxy resin and antimony oxide into the epoxy resin composition, the flame retardancy of the cured epoxy resin composition is increased, thereby improving the heat resistance of the sealing resin. I have. The combination of the above brominated epoxy resin and antimony oxide shows good results in terms of flame retardancy. However, there is a problem in terms of storage stability at high temperatures. That is, in a high temperature state,
Hydrogen bromide is generated by thermal decomposition of brominated epoxy resin,
This hydrogen bromide reacts with the junction between the gold wire of the semiconductor element and the aluminum pad to promote the formation of an alloy, thereby increasing the electric resistance and causing poor conduction. in this way,
In a conventional semiconductor device, there is no problem in terms of flame retardancy, but there is a problem in reliability when left in a high-temperature state, particularly when left for a long time.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor device and an epoxy resin for semiconductor encapsulation which maintain excellent reliability even when left in a high-temperature atmosphere for a long time.
Its purpose is to provide the composition .

[0005]

In order to achieve the above object, a semiconductor device of the present invention comprises the following components (A) to (D)
(However, the components (A) and (B) are represented by the following general formula (2).
Not reacting with the indicated organopolysiloxane. )
And a semiconductor element is sealed with an epoxy resin composition containing 0.5 to 5% by weight of bromine. (A) Epoxy resin. (B) a phenolic resin. (C) Brominated epoxy resin having a bromine content of 25 to 55 % by weight. (D) A hydrotalcite compound represented by the following general formula (1).

[0006]

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[0007]

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Further , the epoxy resin for semiconductor encapsulation of the present invention
The composition comprises the above components (A) to (D) (provided that
The components (A) and (B) are represented by the general formula (2).
Not reacting with luganopolysiloxane. ) Containing
Epoxy resin for semiconductor encapsulation with a bromine content of 0.5 to 5% by weight
The composition is a fat composition.

That is, the present inventors have conducted a series of studies to achieve the above object, and as a result, have found that the halogen ion gas generated during the thermal decomposition of a brominated epoxy resin as a flame retardant is converted into the general It has been found that a special hydrotalcite compound represented by the formula (1) captures and traps and effectively maintains reliability in a high-temperature atmosphere. And, as a result of further study, the trapping effect of the hydrotalcite compound is effective for the brominated epoxy resin having a specific bromine content,
Moreover, the present inventors have found that the bromine content in the entire epoxy resin composition is particularly effective within a specific range, and reached the present invention.

[0010]

Next, an embodiment of the present invention will be described.

The epoxy resin composition used in the semiconductor device of the present invention comprises an epoxy resin (A), a phenol resin (B), a brominated epoxy resin (C) having a bromine content of 25 to 55 % by weight, and It is obtained using the hydrotalcite compound (D) represented by (1),
Usually, it is in the form of a powder or a tablet obtained by compressing it.

The epoxy resin serving as the component A of the above epoxy resin composition is not particularly limited, and various types of conventionally used epoxy resins such as phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A type epoxy resin and the like can be used. Epoxy resin.
These epoxy resins may be used alone or in combination.

Among the above epoxy resins, preferred epoxy resins are novolak type epoxy resins having an epoxy equivalent of 170 to 300, such as phenol novolak type epoxy resin and cresol novolak type epoxy resin.

The phenol resin of component B serves as a curing agent for the epoxy resin, and phenol novolak resins, cresol novolak resins, and the like are preferably used. These phenolic resins have a softening point of 5
The temperature is preferably 0 to 110 ° C and the hydroxyl equivalent is 70 to 150.

[0015] Epoxy resins and phenolic resins, such as described above is one or both, it is preferable to use those which have reacted with O Lugano siloxane.

By using such an epoxy resin or a phenol resin or a modified resin of both, crack resistance and heat cycle resistance are improved. In this case, the amount of the organosiloxane used is based on the total amount of organic components (A + B + C) in the epoxy resin composition.
The content of the organosiloxane is preferably set to 1 to 50% by weight (hereinafter abbreviated as "%"), and more preferably 5 to 30%. That is, if the content of the organosiloxane is less than 1%, a sufficient low stress effect cannot be obtained, and if it is more than 50%, a decrease in resin strength is observed.

The brominated epoxy resin of the component (C) is
There is no particular limitation, and examples thereof include cresol novolak type brominated epoxy resins, phenol novolak type brominated epoxy resins, and bisphenol type brominated epoxy resins. And such a brominated epoxy resin is
It is necessary to use those having a bromine content of 25 to 55 %, preferably 30 to 50%. That is, for the brominated epoxy resin having such a bromine content, the effect of trapping the hydrotalcite compound is sufficiently exhibited, whereby reliability of the semiconductor device in a high-temperature atmosphere can be obtained. Because. Particularly, among the brominated epoxy resins having the above bromine content, the use of a bisphenol-type brominated epoxy having an epoxy equivalent of 420 to 550 gives a good result.

The mutual use ratio of the epoxy resin (including the brominated epoxy resin) and the phenol resin is appropriately selected from the relationship between the epoxy equivalent of the epoxy resin and the hydroxyl equivalent of the phenol resin. It is preferable to set the equivalent ratio of the phenolic hydroxyl group to the equivalent to be in the range of 0.5 to 1.5.

When the equivalent ratio is out of the above range, the curability of the epoxy resin composition tends to be inferior.

The hydrotalcite compound as the component (D) is a special hydrotalcite compound represented by the general formula ( 1 ). This compound traps halogen ions and organic acid ions in the epoxy resin composition by substituting or coordinating with their own CO ₃ ^- ions, and hydrogen bromide resulting from thermal decomposition of the brominated epoxy resin It is considered that an effect of preventing the occurrence of the phenomenon is exerted. The types of the hydrotalcite compounds are classified into many types depending on the ratio of the numbers x, y, and z in the general formula (1). Such hydrotalcite compounds can be used alone or in combination of two or more.

This hydrotalcite compound preferably has an average particle size of 0.5 to 30 μm and a maximum particle size of 74 μm or less from the viewpoint of dispersibility in the epoxy resin composition. And the content of such a D component is
It is preferable to set the amount to be 0.1 to 5% with respect to the resin component (A + B + C) of the epoxy resin composition. That is, if the amount is less than 0.1%, the effect of improving the high-temperature storage characteristics is not sufficiently exhibited, and if it exceeds 5%, a phenomenon of lowering the moisture resistance is observed.

The epoxy resin composition used in the present invention contains, if necessary, other additives conventionally used in addition to the above components A to D.

Examples of the other additives include a curing accelerator, a release agent, a coloring agent, a silane coupling agent and the like.

Examples of the curing accelerator include tertiary amines, quaternary ammonium salts, imidazoles, organic phosphorus compounds and boron compounds. These compounds are used alone or in combination.

Examples of the releasing agent include conventionally known long-chain carboxylic acids such as stearic acid and palmitic acid, metal salts of long-chain carboxylic acids such as zinc stearate and calcium stearate, and waxes such as carnauba wax and montan wax. Can be used.

The epoxy resin composition composed of the above raw materials must have a bromine content of 0.5 to 5%.
That is, when the bromine content is within the above range, the halogen ion trapping effect of the hydrotalcite compound effectively acts.

The epoxy resin composition used in the present invention can be produced, for example, as follows. That is, the above-mentioned A to D component raw materials and the above-mentioned other additives are appropriately blended, and this mixture is melted and mixed in a kneading machine such as a mixing roll machine in a heated state, cooled to room temperature, and then pulverized by a known means. The desired epoxy resin composition can be obtained by a series of steps of tableting as required.

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

The semiconductor device thus obtained sufficiently retains reliability when left at high temperatures.

[0030]

As described above, the semiconductor device of the present invention has the following features.
It is sealed using an epoxy resin composition having a specific bromine content containing a specific brominated epoxy resin (component C) and a special hydrotalcite compound (component D). Since the D component captures a halogen ion generated when left in a high-temperature atmosphere for a long time, it has excellent reliability when left at a high temperature.

Next, examples will be described together with comparative examples.

[0032]

Examples 1-4 and Comparative Examples 1-2 Tables 1 and 2 below
The raw materials as shown in Table 1 were prepared, and the above raw materials were blended at the ratios shown in the same table, kneaded with a mixing roll machine, cooled and pulverized to obtain a desired powdery epoxy resin composition.

[0033]

[Table 1]

[0034]

[Table 2]

Next, the cured product characteristics of the powdery epoxy resin composition obtained as described above were examined and are shown in Tables 3 and 4 below.

[0036]

[Table 3]

[0037]

[Table 4]

In Tables 3 and 4, the coefficient of linear expansion was measured by TMA (manufactured by Rigaku Corporation). The flexural modulus was measured with a Tensilon universal testing machine (manufactured by Toyo Baldwin Co., Ltd.). The volume resistivity was measured according to JIS-K-6911. The measurement of element failure in a high temperature state was performed by assembling a semiconductor device by sealing a semiconductor element with a resin, exposing a total of 20 devices to a high temperature, and evaluating the number by which the number of conductive defects was determined. In the TCT test, the semiconductor element is sealed with a resin, the semiconductor device is assembled, and the temperature is −50 ° C./5 min.
A temperature cycle test was performed 2000 times at / 5 ° C./5 minutes. In the PCT test, the number of aluminum corrosions was measured by leaving the semiconductor device in a pressure cooker state (121 ° C. × 2 atm × 100% RH).

From the results shown in Tables 3 and 4, it can be seen that the example product has higher reliability of the element when left at a high temperature than the comparative example product.

──────────────────────────────────────────────────の Continuing on the front page (51) Int.Cl. ⁶ Identification symbol FI H01L 23/31 (72) Inventor Minoru Minoru 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denki Kogyo Co., Ltd. (72 ) Inventor Fujio Kitamura 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nichidenki Kogyo Co., Ltd. (72) Inventor Kazuo Ika 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nichidenki Kogyo (56) References JP-A-62-254453 (JP, A) JP-A-62-136860 (JP, A) JP-A-55-36215 (JP, A) JP-A-55-165655 (JP, A) JP-A-60-202118 (JP, A) JP-A-61-276851 (JP, A) JP-A-60-147141 (JP, A) JP-A-61-19625 (JP, A) JP-A-1-206655 ( JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) C08L 63/00-63 / 10 C08K 3/26 C08G 59/20 C08G 59/62 H01L 23/29

Claims (2)

(57) [Claims] 1. The following components ( A) to (D) (provided that
The components (A) and (B) are represented by the following general formula (2).
Not reacting with luganopolysiloxane. A semiconductor device in which a semiconductor element is encapsulated with an epoxy resin composition containing 0.5 to 5% by weight of bromine containing ) . (A) Epoxy resin. (B) a phenolic resin. (C) Brominated epoxy resin having a bromine content of 25 to 55 % by weight. (D) A hydrotalcite compound represented by the following general formula (1). Embedded image Embedded image 2. The following (A) to (D) (provided that:
The components (A) and (B) are represented by the following general formula (2).
Not reacting with luganopolysiloxane. ) Containing
Epoxy resin for semiconductor encapsulation with a bromine content of 0.5 to 5% by weight
Fat composition . (A) Epoxy resin. (B) a phenolic resin. (C) Brominated epoxy tree having a bromine content of 25 to 55% by weight
Fat. (D) a hydrotalcite represented by the following general formula (1)
Class compounds. Embedded image Embedded image