JP2002220437A - Thermosetting resin composition and material for sealing semiconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which gives a cured product having excellent moisture resistance and good welding crack resistance, especially a suitable cured product, in a material for sealing semiconductor. SOLUTION: The thermosetting resin composition has, as essential components, a curing agent (A), which comprises a phenolic resin having a structure obtained by adding to an aromatic hydrocarbon containing a phenolic hydroxyl group in a molecule (a) a compound having two ethylenically unsaturated double bonds (b1) and a compound having an ethylenically unsaturated double bond (b2), and an epoxy resin (B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin which provides an excellent cured product having excellent heat resistance and moisture resistance, and is particularly suitable for a semiconductor encapsulant having excellent solder crack resistance during surface mounting. Composition.

[0002]

2. Description of the Related Art As a semiconductor encapsulating material, an epoxy resin composition obtained by curing an orthocresol novolak epoxy resin with a novolak type phenol resin has been used. Recently, progress in semiconductor-related technology has been remarkable. Semiconductors have increased in memory integration,
Although the miniaturization of wiring and the thinning of chips are progressing, the mounting method is also shifting from through-hole mounting to surface mounting as the degree of integration is improved. However, in an automated surface mounting line, an epoxy resin composition that cures an ortho-cresol novolak epoxy resin with a novolak-type phenol resin because the semiconductor package that has absorbed moisture during soldering of the lead wire is rapidly exposed to a high temperature of 200 ° C. or more. Is an inadequate component for solder cracking resistance.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cured resin having excellent moisture resistance and good solder crack resistance, particularly a resin composition which gives a suitable cured material in a semiconductor sealing material. It is.

[0004]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a compound (b1) having an ethylenically unsaturated double bond in an aromatic hydrocarbon (a) containing a phenolic hydroxyl group in the molecule. The present invention has been found that a thermosetting resin composition comprising a curing agent (A) comprising a phenolic resin having a structure to which (b2) is added and an epoxy resin (B) as essential components solves the above-mentioned problems. Was completed.

That is, the present invention relates to a compound (b) having at least two ethylenically unsaturated double bonds in an aromatic hydrocarbon (a) containing a phenolic hydroxyl group in the molecule.
Thermosetting resin comprising a curing agent (A) comprising a phenolic resin having a structure obtained by adding 1) and a compound (b2) having one ethylenically unsaturated double bond and an epoxy resin (B) as essential components Provided are a composition and a semiconductor encapsulating material containing the composition as an essential component.

[0006]

DETAILED DESCRIPTION OF THE INVENTION The phenolic resin (A) used in the present invention comprises a compound (b1) having an ethylenically unsaturated double bond with an aromatic hydrocarbon (a) having a phenolic hydroxyl group in the molecule and (B2) can be obtained by an addition reaction.

At this time, the phenolic resin (A) has a structure having an average of 1.5 or more, preferably 2 to 8 phenolic hydroxyl groups in the molecule, and the curing agent for an epoxy resin according to the present invention. Is preferred.

The above-mentioned aromatic hydrocarbon (a) containing a phenolic hydroxyl group is not particularly restricted but includes, for example, phenol, bisphenol F, bisphenol A, bisphenol AD, bisphenol M, bisphenol C, bisphenol Z, bisphenol TMC. ,
Bisphenols such as fluorene bisphenol, cresol, alkyl-substituted phenols such as p-tert-butylphenol, halogenated phenols such as bromophenol, benzenediols such as hydroquinone and resorcinol, 1-naphthol, 2-naphthol;
Various novolak resins obtained by condensing the above phenols and formaldehyde, such as naphthols such as 6-dihydroxynaphthalene and 2,7-dihydroxynaphthalene, are exemplified. Among them, the above-mentioned bisphenols, benzenediols, and novolak resins are preferred because compounds having two or more phenolic hydroxyl groups in the molecule can be easily produced, and the heat resistance, moisture resistance, and mechanical strength of the cured product are high. Bisphenols and benzenediols are more preferable from a favorable point, and bisphenol A is particularly preferable from an economical viewpoint.

These phenolic hydroxyl group-containing aromatic hydrocarbons (a) can be used alone or in admixture of two or more.

The compound (b1) having an ethylenically unsaturated double bond or the substance (b2) used in the present invention is a compound having at least two ethylenically unsaturated double bonds in one molecule. Examples of (b1) include aromatic divinyl compounds such as divinylbenzene, alkyldivinylbenzene, and diallyl phthalate, and polyfunctional vinyl compounds such as aliphatic polyvinyl compounds such as glycerol diallyl ether and trimethylpropane toluene acrylate. Among them, an aromatic divinyl compound is preferable in terms of excellent reactivity and workability, and divinylbenzene is particularly preferable in terms of heat resistance and moisture resistance. The compound (b1) can be used alone or in combination of two or more.

The compound (b2) having one ethylenically unsaturated double bond used in the present invention is, for example, an aromatic monovinyl compound such as styrene, methylstyrene, ethylstyrene and monobromostyrene; Acrylic acid methyl ester, (meth) acrylic acid stearyl ester, (meth) acrylic acid, N-methylol (meth)
Examples thereof include aliphatic monovinyl compounds such as acrylamide and γ-mercaptopropyltrimethoxysilane. Among them, styrene and ethylstyrene are preferable in terms of compatibility. The compound (b2) can be used alone or in combination of two or more.

The compound (b2) having one ethylenically unsaturated double bond is particularly preferably used as long as a phenol resin having at least two phenolic hydroxyl groups in the molecule can be synthesized.

The compound (b2) having one ethylenically unsaturated double bond is replaced with the compound (b) having at least two ethylenically unsaturated double bonds in one molecule.
The phenolic resin obtained by reacting with the aromatic hydrocarbon (a) containing a phenolic hydroxyl group in combination with 1) is used as a curing agent for an epoxy resin. Only the compound (b1) having at least two ethylenically unsaturated double bonds therein is used together with the aromatic hydrocarbon (b1) containing a phenolic hydroxyl group without using the compound (b2) in combination. Flexibility is better than a cured product using a phenolic resin obtained by the reaction. Among them, the compound (b1) having at least two ethylenically unsaturated double bonds in one molecule is divinylbenzene, and the compound (b2) having one ethylenically unsaturated double bond is ethylstyrene. When using as a use of the resin composition for a semiconductor sealing material, the case of (2) is particularly preferable from the viewpoint of solder crack resistance.

The ratio of the compound (b2) having one ethylenically unsaturated double bond to the compound (b1) having at least two ethylenically unsaturated double bonds in one molecule can be obtained as follows. Compounds (b2) having one ethylenically unsaturated double bond per 100 parts by weight of the total of the compounds (b1) and (b2) from the viewpoint of improving the flexibility and heat resistance of the phenolic resin obtained Is preferably 30 parts by weight or less. Further, from the viewpoint of improving the solder cracking property, it is preferable that the content is 0.5 parts by weight or more based on 100 parts by weight of the total of the compounds (b1) and (b2).
Among them, the compound (b1) having at least two ethylenically unsaturated double bonds in one molecule is divinylbenzene, and the compound (b2) having one ethylenically unsaturated double bond is ethylstyrene. Is particularly preferred when the phenolic resin produced at the above reaction ratio is used as a resin composition for a semiconductor sealing material. Further, when used as a resin composition for a semiconductor encapsulating material, from the viewpoint of good moisture resistance and crack resistance, 5 to 20 parts by weight of ethylstyrene is used per 100 parts by weight of ethylstyrene and divinylbenzene in total. It is particularly preferable to react as

The curing agent (A) comprising a phenolic resin used in the present invention preferably has a structure represented by the following general formula (1).

Embedded image (Wherein, X represents a divalent functional group represented by the following structural formula (2), (3) or (4), a and C each independently represent an integer of 0 or 1, and b represents 1 ≦ b represents an integer of 6 or more.)

Embedded image

Among them, those in which X in the general formula (1) is represented by the structural formulas (3) and / or (4) are particularly preferable.

Although the reaction temperature and the like of the above-mentioned addition reaction are not particularly limited, for example, it is preferable to use a catalyst at 110 ° C. or higher in order to shorten the reaction time reasonably.
As the catalyst used at this time, for example, aluminum chloride, metal chlorides such as stannous chloride, sulfuric acid, hydrochloric acid, inorganic acids such as phosphoric acid, benzenesulfonic acid, organic sulfonic acid such as paratoluenesulfonic acid, Carboxylic acids such as acetic acid, oxalic acid and maleic acid can be used. These catalysts can be used as a mixture of two or more kinds.

The above addition reaction may be carried out in the absence of a solvent, or may be carried out in the presence of an organic solvent. As the organic solvent, any known organic solvents can be used, for example, toluene, xylene, methyl isobutyl ketone,
Dimethylformamide, dimethylsulfoxide, Solvesso and the like can be mentioned.

The reaction rate between the aromatic hydrocarbon (a) containing a phenolic hydroxyl group and the compounds (b1) and (b2) having an ethylenically unsaturated double bond is not particularly limited. In the compounds (b1) and (b2) having an ethylenically unsaturated double bond and the aromatic hydrocarbon (a), the compound (b1) + (B2)] / [the aromatic hydrocarbon containing a phenolic hydroxyl group (a)
= 0.2-0.7 (molar ratio) is preferred. Also,
The compound (b1) having at least two ethylenically unsaturated double bonds in one molecule is divinylbenzene, and the compound (b2) having one ethylenically unsaturated double bond is ethylstyrene. The case is particularly preferred when the phenolic resin produced at the above reaction ratio is used as a resin composition for a semiconductor sealing material.

The properties of the curing agent (A) comprising the phenolic hydroxyl group-containing phenolic resin obtained by the above reaction are not particularly limited, but particularly in the case of a semiconductor encapsulating material, the curing agent (A) is not particularly limited. Viscosity (150 ° C) is 50
mPa · S to 1000 mPa · S is preferred.

The softening point of the curing agent (A) composed of the phenolic resin obtained by the above reaction is not particularly limited. A range from 60C to 100C is preferred.

In the epoxy resin composition used in the present invention,
If necessary, other phenolic resins may be used in combination,
For example, bisphenols, phenol novolak resins, cresol novolak resins, dicyclopentadiene, polyadducts of polycyclic aliphatic hydrocarbons such as tetrahydroindene and phenols, tetramethylbiphenyls, triphenolmethanes, etc. No. Among them,
Cresol novolak resin and dicyclopentadiene
Phenolic resins are preferred.

The epoxy resin (B) used in the present invention is not particularly limited, but examples thereof include bisphenol type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, dicyclopentadiene, tetrahydroindene and the like. Epoxy resin starting from a polyadduct of a polycyclic aliphatic hydrocarbon and a phenol, a tetramethylbiphenyl type epoxy resin,
Triphenolmethane type epoxy resins, alkyl-modified triphenylmethane type epoxy resins and the like can be mentioned. Among them, a cresol novolak type epoxy resin and a dicyclopentadiene-phenol polyaddition type epoxy resin are preferable in terms of heat resistance and moisture resistance.

The amount of the phenolic resin curing agent (A) used in the resin composition of the present invention is such that the epoxy resin (B) is used because the curing reaction proceeds sufficiently and good physical properties of the cured product are obtained.
It is preferable that the amount of the active hydrogen groups in the curing agent be 0.7 to 1.5 equivalents to 1 equivalent of the epoxy group.

The inorganic filler (C) used in the present invention includes fused or crystalline silica powder, glass fiber, carbon fiber, calcium carbonate, quartz, aluminum oxide, magnesium oxide, aluminum hydroxide, magnesium hydroxide, diatomaceous earth. , Calcined clay, carion, mica, asbestos, pulp, wood flour and the like.

Further, if necessary, antimony trioxide,
Flame retardants such as hexabromobenzene, carbon black,
Various additives such as a coloring agent such as redwood, release agents such as natural wax and synthetic wax, and low-stress additives such as silicone oil or rubber may be appropriately compounded.

As the curing accelerator (D) used in the present invention, any known and commonly used curing accelerator can be used. For example,
Tertiary phosphines such as triethylphosphine, tributylphosphine and triphenylphosphine, dimethylethanolamine, dimethylbenzylamine, 2,4,6
Tertiary amines such as tris (dimethylamino) phenol, 2-ethyl-4-methylimidazole, 2,4-
Dimethylimidazole, 2-methylimidazole, 2-
Undecylimidazole, 2-heptadecylimidazole, 1-vinyl-2-methylimidazole, 1-propyl-2-methylimidazole, 2-isopropylimidazole, 1-cyanoethyl-2-ethylimidazole,
1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole,
Such as 1-cyanoethyl-2-phenylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; And imidazoles.

To prepare a molding material for a semiconductor encapsulating material using the resin composition of the present invention, a phenol resin (A),
After uniformly mixing the epoxy resin (B), the inorganic filler (C), the curing accelerator (D), and other additives with a mixer or the like, the mixture is further melt-kneaded with a hot roll or a kneader or the like, and then subjected to low-pressure transfer molding or It can be obtained by injection molding or the like.

[0029]

EXAMPLES The present invention will be described in detail with reference to specific examples below, but the present invention is not limited to these examples. The following parts are all based on weight.

Synthesis Example 1 In a four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel, 1140 g (5 mol) of bisphenol A, 570 g of methyl isobutyl ketone, and 5.7 g of aluminum chloride as a catalyst were added. Temperature. While maintaining the temperature at 113 to 117 ° C., divinylbenzene (374.4 g in total, 2.8
8 mol) and a mixture of ethylstyrene (total 41.6 g,
(0.32 mol) was dropped, and the mixture was reacted for 5 hours. It was taken out of the reaction vessel to obtain a synthetic yellow resin (X1) represented by the general formula (2) and having a softening point of 80 ° C.

Synthesis Example 2 In a four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel, 1140 g (5 mol) of bisphenol A, 570 g of methyl isobutyl ketone, and 5.7 g of aluminum chloride as a catalyst were added. The temperature rose. From the dropping funnel, a mixture of divinylbenzene and ethylstyrene was added dropwise little by little, and the temperature was raised to 140 ° C. using heat generation. While maintaining the temperature at 135 to 145 ° C., divinylbenzene (total 374.4
g: 2.88 mol) and a mixture of ethylstyrene (total of 4).
(1.6 g, 0.32 mol) was added dropwise, followed by a reaction for 3 hours. The resin was taken out of the reaction vessel to obtain a synthetic yellow resin (X2) having a softening point of 80 ° C and represented by the general formula (2).

Synthesis Example 3 1140 g (5 mol) of bisphenol A, 570 g of methyl isobutyl ketone, and 5.7 g of aluminum chloride as a catalyst were added to a four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel. The temperature rose. From the dropping funnel, a mixture of divinylbenzene and ethylstyrene was added dropwise little by little, and the temperature was raised to 140 ° C. using heat generation. While maintaining the temperature at 135 to 145 ° C., divinylbenzene (total 343.2
g: 2.64 mol) and ethyl styrene (total 8).
(5.8 g, 0.66 mol) was added dropwise, followed by a reaction for 3 hours. It was taken out of the reaction vessel to obtain a synthetic yellow resin (X3) having a softening point of 80 ° C and represented by the general formula (2).

Examples 1 to 6 and Comparative Examples 1 and 2 The composition of the present invention will be specifically described in Examples and Comparative Examples.
I will tell. Tables 1 to 4 show the composition of each resin. Each distribution
Mix the mixture at room temperature with a mixer
The mixture was kneaded by a roll, cooled and pulverized to obtain a molding material.
The obtained molding material is tableted, and low-pressure transfer
-175 ° C, 70kg / cm with molding machine ^Two(= 686MP
a), 6 × 6 for solder crack test under conditions of 120 seconds
mm chip was sealed in a 16 pSOP package. Seal
The following heat resistance evaluation and water resistance of the stopped test element
An evaluation and a solder crack test were performed. The evaluation result
The results are shown in Tables 5-8.

Evaluation method Glass transition temperature: A test piece was cut out and a viscoelasticity measuring device (D
MA). Water absorption: Calculated from the rate of weight increase after 300 hours of treatment at 85 ° C. and 85% RH. Solder crack test (1): Twenty sealed test elements were treated under the conditions of 85 ° C. and 85% RH for 72 hours, then immersed in a solder bath at 240 ° C. for 10 seconds, and external cracks were observed with a microscope. The ratio of the number of test elements having external cracks to the total number of the test elements was calculated and shown. Solder crack test (2): Twenty sealed test elements were treated for 144 hours under the conditions of 85 ° C. and 85% RH, and then immersed in a solder bath at 240 ° C. for 10 seconds, and external cracks were observed with a microscope. The ratio of the number of test elements having external cracks to the total number of the test elements was calculated and shown.

The resin used (the unit of the hydroxyl equivalent and the epoxy equivalent of the following resin is gram / equivalent and
Expressed as eq.・ Synthesis Example 1 Synthesized resin (X1); hydroxyl equivalent 160 g / eq. Softening point 80 ° C. ・ Synthesis 2 Synthesized resin (X2); hydroxyl equivalent 160 g / eq. Softening point 80 ° C. ・ Synthesis 3 Synthesized resin (X3); hydroxyl equivalent 160 g / eq. Softening point 80 ° C. ・ Phenol novolak resin (X4); hydroxyl equivalent 104 g / e
q, Softening point 80 ° C Daino Ink Chemical Industry's phenolite TD-2131 ・ Epoxy resin (Y1); Orthocresol novolak-type ethoxy resin ethoxy equivalent 250g / eq, softening point 67 ° C: Dainippon Ink & Chemicals EPI
CLON N-665 ・ Epoxy resin (Y2); dicyclopentadiene-phenol polyaddition epoxy resin ethoxy equivalent 263 g / eq, softening point 65 ° C: Dainippon Ink and Chemicals EPI
CLON HP-7200

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

[Table 4]

[0040]

[Table 5]

[0041]

[Table 6]

[0042]

According to the present invention, a resin composition suitable for a semiconductor encapsulating material having excellent heat resistance and moisture resistance and excellent in solder crack resistance during surface mounting is provided. Can be provided.

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Hideki Kano 5-2292-7 Kemigawa-cho, Hanamigawa-ku, Chiba-shi, Chiba 4F032 CA04 CA14 CB05 CC01 CD00 CD01 CE03 CG00 4J036 AA01 AC02 AD01 AD08 AF01 AF06 AF08 AK19 DA02 DC02 DC05 DC41 DD07 FA01 FA05 FA06 FB08 FB18 JA07 4M109 AA01 CA21 EA02 EB03 EB04 EB13 EC01 EC03 EC05

Claims (7)

[Claims] 1. A compound (b1) having at least two ethylenically unsaturated double bonds in an aromatic hydrocarbon (a) containing a phenolic hydroxyl group in the molecule and one ethylenically unsaturated double bond A thermosetting resin composition comprising, as essential components, a curing agent (A) composed of a phenol resin having a structure to which a compound (b2) having the compound is added and an epoxy resin (B). 2. The compound (b1) having at least two ethylenically unsaturated double bonds is a divinylbenzene and the compound (b) having one ethylenically unsaturated double bond
The resin composition according to claim 1, wherein 2) is an ethylstyrene. 3. The thermosetting resin composition according to claim 2, wherein the curing agent (A) comprising a phenol resin is a phenol resin represented by the following general formula (1). Embedded image (Wherein, X represents a divalent functional group represented by the following structural formula (2), (3) or (4), a and C each independently represent an integer of 0 or 1, and b represents 1 ≦ b represents an integer of 6 or more.) 4. In the general formula (1), X represents the structural formula (3)
The thermosetting resin composition according to claim 3, which is represented by (4). 5. The epoxy resin (B) is a dicyclopentadiene-phenol polyaddition type epoxy resin.
5. The resin composition according to any one of items 4 to 4. 6. The resin composition according to claim 1, further comprising an inorganic filler (C) and a curing accelerator (D). 7. A semiconductor encapsulating material comprising the thermosetting resin composition according to claim 1.