JPH0243205A - Sealing resin composition for semiconductor - Google Patents

Abstract

PURPOSE:To reduce the stress and improve the thermal shock resistance, soldering heat resistance, etc., by mixing a bismaleimide compound with a phenol aralkyl resin and/or a resorcinol aralkyl resin. CONSTITUTION:The title composition is obtained by mixing 100 pts.wt. bismaleimide compound of formula I [wherein R is phenylene or a group of formula II (wherein X is a direct bond, or a divalent group selected from among a 1-10C hydrocarbon group, isopropylidene hexafluoride, carbonyl, thio, sulfinyl, sulfonyl, oxide, etc.)], for example, N,N'-2,2-bis[4-(3-aminophenoxy) phenyl]propanebismaleimide, with 10-500 pts.wt. phenol aralkyl resin (e.g., Xylok XL-225, a product of Mitsui Toatsu) and/or resorcinol aralkyl resin (e.g., Resorcin Xylok, a product of Mitsui Toatsu).

Description

[Detailed description of the invention] [Industrial application field] The present invention requires low stress, low coefficient of thermal expansion, and high reliability with excellent thermal shock resistance and soldering heat resistance without impairing heat resistance. The present invention relates to a semiconductor encapsulating resin composition suitable for encapsulating electronic components such as semiconductors.

[Conventional technology]

In recent years, so-called plus-thousand sealing, which uses thermosetting resins such as epoxy resins, has been widely put into practical use as a method for sealing semiconductors, taking advantage of its economic advantages such as inexpensive raw materials and suitability for mass production. . In particular, resin compositions containing polyfunctional epoxy resins, novolanc type phenolic resins, and inorganic fillers as main components have become mainstream as sealing resins because they have excellent heat resistance, moldability, and electrical properties.

[Problem to be solved by the invention]

On the other hand, as semiconductor chips have become more expensive, their chip sizes have become larger. In addition, the shape of the package has become smaller and smaller as seen in the Furanoto package, as opposed to the larger size of the 1000 knobs, due to higher density mounting on boards and surface mounting.
There is a trend toward thinner products. For this reason, defective phenomena that were not observed with conventional sealing resins have been introduced. In other words, stress in the resin due to the difference in coefficient of thermal expansion between the sealing resin and the chip increases the size of the chip and the thinning of the resin layer, causing thermal shock that can cause cranking of the passivation film, misalignment of the aluminum wiring, or damage to the sealing resin. Also, as the package itself is exposed to the solder bath temperature due to surface mounting, the moisture inside the pan cage expands rapidly, causing a crack phenomenon in the package and reducing the moisture resistance of the semiconductor. , which in turn causes a decline in credibility. Therefore, it is desired to develop a sealing resin that has less stress and excellent solder heat resistance.

One possible way to reduce stress is to reduce the coefficient of thermal expansion of the resin to reduce the difference between it and that of the chip, but the difference between the coefficient of thermal expansion of the resin and that of the chip is large, so in order to reduce this requires the use of a large amount of inorganic filler with a low coefficient of thermal expansion in the resin, but currently a considerable amount of inorganic filler is already being used, and further increasing this amount may cause deterioration of moldability. Become. On the other hand, attempts have been made to add plasticizers or to use flexible epoxy resins or phenolic resins in order to lower the elastic modulus of the resin and reduce stress, but these methods have not produced results. The cured product had a problem in heat resistance.

In addition, as exemplified by JP-A-58-108220, a method of dispersing rubber particles in a sealing resin to provide crack resistance while maintaining heat resistance has also been invented, but methods such as solder bath etc. There were several problems such as poor impact resistance at high temperatures exceeding the glass transition temperature of the sealing resin.

The present invention provides low stress (
The object of the present invention is to provide a resin composition for semiconductor encapsulation that has excellent thermal shock resistance, soldering heat resistance, and the like.

[Means to solve problems]

As a result of various studies, the present inventors discovered that a curing reaction between a bismaleimide compound having a specific structure and a specific aralkyl resin reduces stress and provides a resin with excellent impact resistance. The present invention has been achieved.

That is, the present invention represents a divalent group consisting of the general formula (+), where X is a direct bond and has 1 to 10 carbon atoms.
(representing a group selected from the group consisting of a divalent hydrocarbon group, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group, a sulfonyl group, or an oxide) and a resin composition for semiconductor encapsulation which contains a phenol aralkyl resin and/or a resorcin aralkyl resin as an essential component.

The bismaleimide compound represented by the general formula (+) can be easily produced by a condensation/dehydration reaction between a diamine compound represented by the general formula (■) and maleic anhydride by a commonly known method.

(In the formula, R represents the same meaning as above) The diamine compound (II) is specifically 1.3-bis(3-aminophenoxy)henzen, bis(3-aminophenoxy)methane, 1.3-bis(3-aminophenoxy)methane, 1. 1-bis[4-(3-aminophenoxy)phenyl]ethane, 1.2-bis[4(3-aminophenoxy)phenyl]ethane, 2.2bis(4-(3-aminophenoxy)phenyl)propane, 2.2-bis(4
-(3-aminophenoxy)phenyl]butane, 2.2
-bis(4-(3-aminophenoxy)phenyl)-1
,1,L3,3.3-hexafluoropropane, 4.4
'-Bis(3-aminophenoxy)biphenyl, bis(
4-(3-aminophenoxy)phenyltaketone, bis[4-(3-aminophenoxy)phenyl fusulfide, bis(4-(3-aminophenoxy)phenyl]sulfoxide, bis(4-(3-aminophenoxy)phenyl) ] Sulfone, bis(4(3-aminophenoxy)phenyl ether, etc.).

Specifically, the bismaleimide compound obtained by the condensation/dehydration reaction of the diamine compound of general formula (II) and maleic anhydride is N,N'-1,3-bis(3-aminophenoxy)benzene bismaleimide. , N, li'-bis(4
-(3-aminophenoxy)phenylcomethanebismaleimide, N,N'-1,1-bis[4-(3-aminophenoxy)phenyl]ethanebismaleimide, N,N'
-1,2-(4-(3-aminophenoxy)phenyl)
Ethane bismaleimide, N, N'-1,2-(4-(3
-aminophenoxy)phenyl]ethane bismaleimide, N,N'-2,2-bis(4-(3-aminophenoxy)phenyl)propane bismaleimide, N,N'-2
,2bis(4-(3-aminophenoxy)phenylcobutanebismaleimide,N,N'-2,2-bis(4-(
3-aminophenoxy)phenyl-1,1,1,3,3
,3-hexafluoropropane bismaleimide, N,N
'-4,4''-bis(3-aminophenoxy)biphenylbismaleimide, N,N'-bis(4-(3-aminophenoxy)phenylkoketone bismaleimide, N,N
o-His[4(3-aminophenoxy)phenyl]sulfide bismaleimide, N,N'-bis(4-(3-aminophenoxy)phenyl)sulfoxide bismaleimide, N,N"-bis(4-(3- aminophenoxy)phenyl]sulfone bismaleimide, N,N'-bis[4
-(3aminophenoxy)phenyl]ether and the like.

Including workability and moldability, N,N'-2,2-bis(4-(3-aminophenoxy)phenyl)propane bismaleimide, N,N'-bis(4-(3-aminophenoxy)phenyl) ] Sulfide bismaleimide is superior.

Moreover, the above-mentioned bismaleimides may be used alone or in combination of two or more kinds. Furthermore, maleimide compounds other than (1) may be used in combination if necessary.

The aralkyl resin used in the present invention has two or more active OH groups and has R3R- as a repeating unit in its molecular structure. Phenol aralkyl resin is a resin made by reacting an aralkyl ether with phenol, and a specific example thereof is Zyrosoku XL-225 (=Seito Atsushi Kagaku ■, softening point: 85°C to 105°C). Furthermore, the resorcin aralkyl resin used in the present invention is a resin made by reacting an aralkyl ether with resorcin, and specifically, resorcin aralkyl resin (Mitsui Toatsu Chemical ■, softening point 85°C) is used.
~105°C).

The amount of these aralkyl resins used is usually in the range of 10 to 500 parts by weight per 100 parts by weight of the bismaleimide compound.

In the present invention, the resin composition may be blended and kneaded in the usual manner, the bismaleimide compound may be dissolved in advance in the phenol aralkyl resin and/or the resorcin aralkyl resin, or a prepolymer made by reacting both. may be used. In particular, when a prepolymer is used, it is excellent in terms of moldability and curability.

In the present invention, when curing the resin composition, it is preferable to use phosphines as a curing accelerator. Examples of the phosphine include tributylphosphine, tri-4-methylphenylphosphine, tri-4-methoxyphenylphosphine, tributylphosphine, trioctylphosphine, tri-2-cyanoethylphosphine, and the like.

The amount of phosphines used is 0.00 parts by weight based on the total amount of bismaleimide compound and novolac type phenol resin (101) parts by weight.
1 to 10 parts by weight is preferred.

Furthermore, an organic peroxide or an ab compound can be used in combination as necessary. Examples of organic peroxides include di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 1.3-bis-(t-butylperoxy-isopropyl)benzene, and 1.1-di-t-butyl peroxide. -butylperoxy-3,3,5-trimethylcyclohexane,
Examples include dialkyl peroxides such as 1.1 to di-t-butyl peroxycyclohexane, and alkyl peresters such as L-butyl perbenzoate. Examples of the azo compound include azobisisobutyronitrile and azobisdimethylvaleronitrile.

The amount of the organic peroxide or azo compound added is preferably 0.1 to 5 parts by weight per 100 parts by weight of the bismaleimide resin.

Furthermore, imidazoles, tertiary amines,
grade ammonium salt, metal compound, tris(3,6-
A curing accelerator such as tris(polyoxaalkyl)amines represented by cyoxyheptyl)amine can also be used in combination. Particularly when using a prepolymer of a maleimide compound and a phenol, tris(polyoxaalkyl)amines are preferred.

In addition to the above-mentioned compositions, the composition of the present invention may optionally include epoxy resins, phenol aralkyl resins or phenolic resins other than resorcin aralkyl resins, various amines, various reactive diluents, silicone oil, fillers, and silane coupling agents. , mold release agent, coloring agent, flame retardant, etc.
Mix and knead to make a molding material.

〔Example〕

Examples 1 to 7 Bismaleimide compound, phenol aralkyl resin, resorcin aralkyl resin, curing accelerator, organic peroxide, quaternary ammonium salt, silica powder, silane coupling agent, wax, coloring with the formulation shown in Table 1. A molding material was obtained by blending a flame retardant and a flame retardant and kneading with rolls.

Comparative Example 1.2 A molding material was obtained by mixing and kneading a bismaleimide compound other than the bismaleimide compound represented by the general formula (1) and a novolak type phenol resin in the same manner as in the example, according to the formulation shown in Table 1.

Comparative Example 2 A molding material was obtained by blending and kneading a bismaleimide compound and a novolank type phenol resin in the same manner as in the example, according to the formulation shown in Table 1.

Comparative Example 3 A molding material was obtained by blending and kneading an epoxy resin and a novolac type phenol resin in the same manner as in the example, according to the formulation shown in Table 1.

Using each molding material, transfer molding (180°C1
30Kg/cd for 3 minutes), test Noroopia 7 rat package (20asX30snX 2.5
m+w, 12 mm x 12 m+* test element mounted) and test pieces for measuring physical properties were molded and post-cured at 180°C for 6 hours.

The test results are shown in Table 2.

〔Effect of the invention〕

As explained in the Examples and Comparative Examples, the resin composition for semiconductor encapsulation according to the present invention is superior to the conventional encapsulation resins mainly composed of polyfunctional epoxy resins and novolak phenol resins. It has a high glass transition temperature and low thermal expansion.It also has a low water absorption rate and high flexibility compared to sealing resins whose main components are a bismaleimide compound and a novolac type phenolic resin other than the combination of the present invention. It has low stress, high fluidity, and excellent soldering heat resistance. Furthermore, only the example of the present invention is excellent in soldering heat resistance for a 12 m square chip.

A large semiconductor device with a high degree of integration, using the resin composition of the present invention,
Alternatively, when used for sealing a surface-mounted semiconductor device, excellent reliability can be obtained, making it an industrially useful invention.

Patent applicant: Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] (1) General formula (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) (In the formula, R is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Represents a divalent group, X is a direct bond, and has 1 to 10 carbon atoms
represents a group selected from the group consisting of a divalent hydrocarbon group, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group, a sulfonyl group, or an oxide. ) A resin composition for semiconductor encapsulation, which contains a bismaleimide compound represented by the following and a phenol aralkyl resin and/or a resorcin aralkyl resin as essential components.