JP2576701B2 - Epoxy resin composition and semiconductor device - Google Patents

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 having good fluidity, low stress, low expansion coefficient, low moisture absorption, high glass transition temperature, and a cured product excellent in moisture resistance and the like. And a semiconductor device sealed with a cured product of the epoxy resin composition.

[0002]

2. Description of the Related Art A curable epoxy resin, a curing agent and an epoxy resin composition containing various additives are generally more moldable and more adhesive than other thermosetting resins. Because of its excellent electrical properties, mechanical properties, moisture resistance, and the like, semiconductor devices are often sealed with an epoxy resin composition.

However, in the field of semiconductor devices in recent years, the package size and the thickness have been reduced, while the semiconductor elements have been increased in size. Such a semiconductor device has been sealed with a conventional epoxy resin composition. When stopped, the difference in dimensional change due to heat between the semiconductor element and the epoxy resin composition causes a problem that stress applied to the semiconductor element increases, and in a step of performing a soldering process after absorbing moisture,
Problems such as cracks in the package have also arisen.

[0004] In order to solve these problems, the present applicant has previously disclosed an epoxy resin composition in which an organopolysiloxane was blended with a curable epoxy resin (Japanese Patent Application Laid-Open No. 56-129246), and an aromatic polymer and an organopolysiloxane. Resin composition to which a block copolymer consisting of the following has been added (Japanese Patent Application Laid-Open No. 58-21417), a triphenolalkane-type epoxy resin or an epoxy resin containing the polymer as a main component, a novolak-type phenol resin or A resin-encapsulated semiconductor device containing a phenol alkane type phenol resin and an organopolysiloxane (JP-A-63
No. 226951), and proposed a low-stress epoxy resin composition to solve the problem.

[0005] However, even with the above-mentioned epoxy resin composition having a reduced stress, it is difficult to completely satisfy the recent demands for encapsulation of semiconductor devices, which are increasingly sophisticated. That is, at present, there is a demand for further lowering the stress of the semiconductor encapsulating resin, good fluidity at the time of molding, mechanical strength such as flexural strength and flexural modulus, high glass transition temperature, moisture resistance and the like. There is a demand for the development of a resin composition for semiconductor encapsulation that gives a cured product having excellent properties.

The present invention has been made in view of the above circumstances,
Epoxy resin composition having good fluidity, low stress, low expansion coefficient, low moisture absorption, high glass transition temperature, and a cured product having good moisture resistance and mechanical strength, and the epoxy resin composition It is an object to provide a semiconductor device sealed with a cured product.

[0007]

The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, (A) an epoxy resin having a naphthalene ring represented by the following formula (1); (2) an epoxy resin composition containing a curing agent having a triphenolalkane-type resin represented by the formula as a main component and (C) an inorganic filler; and (A) a naphthalene ring represented by the following formula (1): (B) a curing agent mainly containing a substituted or unsubstituted novolak type phenol resin and / or a triphenolalkane type resin represented by the following formula (2), (C) an inorganic filler and (D) An epoxy resin composition containing a block copolymer obtained by an addition reaction between an organic polymer represented by the following formula (3) and an organopolysiloxane represented by the following formula (4) is flowable. Good, low stress, low coefficient of expansion, extremely low water absorption, high glass transition temperature, and gives a cured product with good moisture resistance, mechanical strength, and adhesiveness. The composition can be effectively used for sealing any type of semiconductor device such as a DIP type, a flat pack type, a PLCC type, and an SO type, and has extremely excellent characteristics for sealing this type of semiconductor device. The inventors have found that the present invention has been performed, and have accomplished the present invention.

That is, the present invention provides: (A) an epoxy resin represented by the following general formula (1); (B) a curing agent mainly containing a triphenolalkane type resin represented by the following general formula (2); C) An epoxy resin composition comprising an inorganic filler is provided. Further, the present invention provides (A) an epoxy resin represented by the following general formula (1), (B) a substituted or unsubstituted novolak-type phenol resin and / or a triphenolalkane-type resin represented by the following general formula (2) (C) an inorganic filler, (D) obtained by an addition reaction of an organic polymer represented by the following general formula (3) and an organopolysiloxane represented by the following general formula (4). Provided is an epoxy resin composition comprising a block copolymer. Furthermore,
The present invention provides a semiconductor device sealed with a cured product of the above epoxy resin composition.

[0009]

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[0010]

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[0011]

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[0012]

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Hereinafter, the present invention will be described in more detail. The epoxy resin composition according to the present invention contains (A) an epoxy resin, (B) a curing agent, and (C) an inorganic filler, as described above. It becomes.

The epoxy resin (A) is represented by the following general formula (1) and has a naphthalene ring, so that it has a high glass transition temperature, a small water absorption,
It also has excellent toughness.

[0015]

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In the above formula (1), R ¹ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, OG is a glycidyl ether group,
m is an integer of 0 to 2, n is 1 or 2, and k is an integer of 0 to 3. Here, OG may be added to any of the rings of the naphthalene ring, or may be added to both of the rings at the same time (the same applies hereinafter). As the alkyl group having 1 to 10 carbon atoms of ^{R 1,} a methyl group, an ethyl group, a propyl group, t-
Examples thereof include a butyl group and an octyl group.

Specific examples of the epoxy resin represented by the general formula (1) include the following compounds.

[0018]

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The above epoxy resins can be used alone or as a mixture of two or more. In addition, the epoxy resin is a novolak type epoxy resin or a bisphenol A type epoxy resin, and a substituted epoxy resin in which a halogen atom such as chlorine or bromine atom is introduced.
Mono-epoxy compounds of styrene oxide, cyclohexene oxide, phenylglycidyl ether and the like may be used in combination.

The synthesis of the epoxy resin represented by the above formula (1) can be carried out, for example, by reacting a naphthalene ring-containing polymer having a phenolic hydroxyl group with epichlorohydrin.

The component (B) is used as a curing agent for the epoxy resin of the component (A), and contains a triphenolalkane type resin as a main component. When a specific block copolymer of the component (D) described later is blended, the component (B) may be mainly composed of a substituted or unsubstituted novolak-type phenol resin.

Here, specific examples of the substituted or unsubstituted novolak type phenol resin include the following compounds.

[0023]

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On the other hand, the triphenol alkane type resin is
It is represented by the following general formula (2), and specific examples include the following compounds.

[0025]

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[0026]

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If necessary, a curing agent other than the novolak-type phenol resin and the triphenolalkane-type resin, for example, diaminodiphenylmethane, may be added to the component (B).
An amine-based curing agent represented by diaminodiphenylsulfone, metaphenylenediamine and the like, and an acid-based curing agent such as phthalic anhydride, pyromellitic anhydride and benzophenonetetracarboxylic acid can also be blended.

The amount of the component (B) is not particularly limited, but the molar ratio of the phenolic OH group contained in the phenol novolak resin or the triphenolalkane resin to 1 mol of the epoxy group contained in the component (A) is not limited. 0.1-3
Mol / mol, preferably 0.5 to 1.5 mol / mol.

As the inorganic filler of the component (C), crystalline or non-crystalline quartz powder is typically exemplified, and alumina, BN, silicon nitride, aluminum nitride and the like can also be used. The shape of the quartz powder is spherical,
Any of crushed particles can be used, but it is preferable that coarse particles of 75 μm or more are reduced to 0.3% by weight or less of the entire quartz powder in order to prevent local stress applied to the semiconductor element. Also,
In order to improve the fluidity of the composition, the average particle size is 0.4 to 2
μm spherical silica in 5 to 20 parts by weight of 100 parts by weight of all quartz powder.
It is desirable to use parts by weight. It is also effective to subject these quartz powders to a surface treatment with a silane coupling agent before use. The compounding amount of the component (C) is 350 to 700 with respect to 100 parts by weight of the total amount of the components (A) and (B).
The preferred range is 400 parts by weight, especially 400 to 650 parts by weight.
If the amount is more than this range, not only the dispersion becomes difficult, but also the workability, low stress and physical properties of crack resistance become disadvantageous, while if the amount is too small, the expansion coefficient may increase.

Further, the component (D) of the epoxy resin composition of the present invention comprises a block obtained by an addition reaction of an organic polymer represented by the following formula (3) and an organopolysiloxane represented by the following formula (4). The epoxy resin composition of the present invention can further improve the crack resistance and the like of the epoxy resin composition of the present invention.

To explain this, the organic polymer constituting the block copolymer of the component (D) is represented by the following general formula (3).

[0032]

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In the formula, A is the same or different group selected from an organic group having 1 to 10 carbon atoms containing an —OH group, an —OG group, and an alkenyl group, and A is any of naphthalene rings. It may be added to a ring, or may be added to both rings simultaneously (the same applies hereinafter). R ¹ , —OG, m, n
And k have the same meaning as described above.

The alkenyl group contains 1 to 1 carbon atoms.
Examples of the organic group No. 10 include a vinyl group, an allyl group and —OCH ₂ C (OH) HCH ₂ OCH containing these groups.
₂ CH = CH ₂ and the like, but may be any as long as it can be an addition reaction with the ≡SiH group of the organohydrogenpolysiloxane.

Specific examples of the organic polymer represented by the formula (3) include the following compounds.

[0036]

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[0037]

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In the above compounds, it is preferable that any substituent added to the naphthalene ring is added to the inner ring of the naphthalene ring.

On the other hand, an organopolysiloxane represented by the following general formula (4) is used.

[0040]

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Here, R ² is a hydrogen atom or — (CH
₂ ) _p- NH ₂ (p is an integer of 0 to 5, R ³ is a monovalent organic group, a and b are 0.001 ≦ a ≦ 1, 1 ≦ b <3, 1.0
A positive number satisfying 01 ≦ a + b ≦ 3, and at least one ≡SiH group or ≡Si (CH ₂ ) _p NH in one molecule
₂ In addition, as a monovalent organic group of R ³ , a hydroxyl group or a group having 1 to 10 carbon atoms is preferable, and a methyl group,
Ethyl group, vinyl group, phenyl group, monovalent hydrocarbon group such as benzyl group, chloropropyl group, chloromethyl group, substituted monovalent hydrocarbon group such as glycidylpropyl group, and methoxy group, alkoxy group such as ethoxy group, Further, there may be mentioned the same or different groups selected from alkenyloxy groups such as isopropenyloxy group and isobutenyloxy group.

In this case, in the organopolysiloxane of the formula (4), as the organohydrogenpolysiloxane having a ≡SiH group in which R ² is a hydrogen atom, particularly, both-end hydrogenmethylpolysiloxane and both-end hydrogenmethylmethyl -(2-trimethoxysilylethyl) polysiloxane is preferably used, and specific examples include the following compounds.

[0043]

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In the organopolysiloxane of the formula (4), R ² is — (CH ₂ ) _p —NH ₂ group.
Specific examples of the organopolysiloxane having an i- (CH ₂ ) _p —NH ₂ group include the following compounds.

[0045]

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The block copolymer of the component (D) is obtained by an addition reaction of the above-mentioned organic polymer having an alkenyl group with an organopolysiloxane having a ≡SiH group, or an organic polymer having an epoxy group and-(CH ₂ ) It can be obtained by an addition reaction with an organopolysiloxane having a _p- NH ₂ group.

These addition reactions can be carried out by employing a conventionally known method. For example, an alkenyl group and ≡SiH
In the case of an addition reaction with a group, the reaction is carried out in an inert solvent such as benzene, toluene or methyl isobutyl ketone in the presence of a conventionally known addition catalyst, for example, a platinum-based catalyst such as chloroplatinic acid.
The reaction can be carried out by heating to 0 to 120 ° C. to cause a reaction. In this case, during the addition reaction, the molar ratio of alkenyl group / ≡SiH group is 1 or more, preferably 1.5
It is preferably set to 10 to 10. In addition, the epoxy group and-
_{(CH 2)} reaction with p -NH ₂ group, for example a solventless or toluene, can be carried out by heating to 60 to 170 ° C. in an inert solvent such as methyl isobutyl ketone.

The amount of the component (D) block copolymer to be used may be one kind alone or two or more kinds in combination (A)
2 to 5 per 100 parts by weight of the total amount of the component and the component (B)
It is preferably in the range of 0 parts by weight. If the amount of the block copolymer is less than 2 parts by weight, the effect of improving crack resistance may not be sufficiently achieved, and 50
When the amount exceeds the weight part, the mechanical strength may be reduced.

The ratio of the amount of epoxy group (a mol) and the amount of phenolic hydroxyl group (b mol) contained in the components (A), (B) and (D) is a / b = 0. 5-
It is desirable to be in the range of 1.5, and if a / b is outside the above range, it may be disadvantageous in physical properties such as curability and low stress.

The epoxy resin composition of the present invention may contain a curing catalyst. Examples of the curing catalyst include an imidazole compound, a tertiary amine compound, and a phosphorus-based compound.
A combined catalyst using diazabicyclo (5.4.0) undecene-7 and triphenylphosphine in a weight ratio of 0: 1 to 1: 1, preferably 0.01: 1 to 0.5: 1 It is preferable that If the ratio of 1,8-diazabicyclo (5.4.0) undecene-7 is higher than the above range, the glass transition temperature may decrease. The addition amount of the combined catalyst is not particularly limited, but is 0.2 to 2 parts by weight, particularly 0.4 to 1.2 parts by weight based on 100 parts by weight of the total of the components (A) and (B). It is desirable.

Various additives can be further added to the composition of the present invention, if necessary. For example, reactive or non-reactive thermoplastic elastomers, low stress agents such as silicone gel, silicone rubber, silicone oil, waxes, release agents such as fatty acids such as stearic acid and metal salts thereof, and pigments such as carbon black , Flame retardants, surface treatment agents (γ-glycidoxypropyltrimethoxysilane, etc.),
One or more of coupling agents such as epoxy silane, vinyl silane, boron compound, and alkyl titanate, an antioxidant, and other additives can be blended.

In the production of the epoxy resin composition of the present invention, predetermined amounts of the above-mentioned components are uniformly stirred and mixed in the production thereof, and kneaded and cooled by a kneader, roll, extruder or the like which has been heated to 70 to 95 ° C. And pulverized. Here, there is no particular limitation on the order of compounding the components.

The composition of the present invention thus obtained is DIP
Mold, flat-pack mold, PLCC mold, SO mold, etc., can be effectively used for sealing, and in this case, molding is performed by a conventionally used molding method, for example, transfer molding,
Injection molding, casting and the like can be employed. The molding temperature of the epoxy resin composition was 150
~ 180 ℃, post cure at 150 ~ 180 ℃
It is preferably performed for 16 hours.

[0054]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to 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 and Comparative Examples In addition to the components shown in Table 1, 0.6 part of a curing catalyst, 0.5 part of triphenylphosphine, 8 parts of Sb ₂ O ₃ and 1.5 parts of carbon black Parts, 1 part of carnauba wax, γ
-Melting and mixing uniformly 3 parts of glycidoxypropyltrimethoxysilane with a hot double roll, cooling,
This was crushed to obtain an epoxy resin composition. Table 2 shows the epoxy resins used, and Table 3 shows the curing agents.

With respect to these compositions, the following (A) to (A)
Various tests of (i) were performed. The results are also shown in Table 1. (A) Spiral flow value 180 ° C., 70 ° C. using a mold conforming to the EMMI standard
It was measured under the condition of kg / cm ² . (B) Mechanical strength (flexural strength and flexural modulus) 180 ° C, 70 kg / cm according to JIS-K6911
^{2. A} bending rod of 10 × 4 × 100 mm was formed under the condition of a molding time of 2 minutes, and post-cured at 180 ° C. for 4 hours. (C) Expansion coefficient, glass transition temperature Using a test piece having a diameter of 4 mm x 15 mm, the value when the temperature was increased at a rate of 5 ° C per minute by a dilatometer was measured. (D) Crack resistance A silicon chip having a size of 9.0 × 4.5 × 0.5 mm is bonded to a 14 PIN-IC frame (42 alloy).
The epoxy resin composition was molded thereon under the molding conditions of 180 ° C. × 2 minutes, and post-cured at 180 ° C. for 4 hours.
A heat cycle of 96 ° C. × 1 minute to 260 ° C. × 30 seconds was repeatedly applied, and the resin cracking rate after 300 cycles was measured (measured number = 50). (E) Crack resistance after moisture-absorbing solder (I) A silicon chip having a size of 8.0 × 10.0 × 0.5 mm was bonded to a flat package having a size of 10 × 14 × 2.3 mm, and was bonded thereto. Molding condition 1 for epoxy resin composition
It was molded at 80 ° C. for 2 minutes and post-cured at 180 ° C. for 4 hours. This was left in an atmosphere of 85 ° C./85% RH for 72 hours, immersed in a solder bath at a temperature of 240 ° C., and the time (sec) until a package crack occurred was measured. (F) Crack resistance after moisture absorption soldering (II) A silicon chip having a size of 2 × 4 × 0.4 mm was 4 × 1
It was adhered to a 2 × 1.8 mm SO package, and the epoxy resin composition was molded thereon under molding conditions of 175 ° C. × 2 minutes.
Post-curing was performed at 80 ° C. for 4 hours. 85 ℃ / 8
After standing in an atmosphere of 5% RH for 72 hours,
C. in a solder bath. Next, this package was disassembled, and the occurrence of internal cracks was observed with an optical microscope. FIG. 1 shows a state in which an internal crack has occurred. In addition,
In the figure, 1 is a silicon chip, 2 is a frame, 3 is a sealing resin, and 4 is a crack. (G) Adhesiveness The package shown in FIG. 2 was molded under molding conditions of 175 ° C. × 2 minutes, post-cured at 180 ° C. for 4 hours, and then pulled out of a frame (material: 42 alloy, thickness: 0.25 mm). It was measured. In addition, in FIG. 2, 5 is a frame, 6
Is a sealing resin. The dimensions are mm. (H) Moisture resistance A silicon chip having a size of 9.0 × 4.5 × 0.5 mm was bonded to a 20-pin PLCC frame, and an epoxy resin composition was formed thereon under molding conditions of 180 ° C. × 2 minutes.
Post-curing was performed at 80 ° C. for 4 hours. 130 ° C /
It was left in an atmosphere of 85% RH, a bias of 20 V was applied, and the defect rate due to aluminum corrosion after 100 hours was measured. (I) A disk having a diameter of 50 mm × 2 mm was formed under the conditions of a water absorption of 180 ° C., 70 kg / cm ² and a forming time of 2 minutes, and was post-cured at 180 ° C. for 4 hours. It was left for a while, and the water absorption was measured.

[0057]

[Table 1]

[0058]

[Table 2]

[0059]

[Table 3]

[0060]

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[0061]

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Curing catalyst 1,8-diazabicyclo (5.4.0) undecene-7
And a phenol novolak resin (TD2131, manufactured by Dainippon Ink) at a ratio of 20/80 weight ratio at 130 ° C. × 3.
Heat-mixed for 0 minutes, then finely pulverized to 50 μm or less. Quartz powder (1) fused spherical silica having a specific surface area of 1.4 m ² / g and an average particle size of 15 μm (coarse particles of 75 μm or more and 0.1% or less) quartz powder (2) specific surface area of 2.5 m ² / g and average particles Fused crushed silica having a diameter of 10 μm (coarse grains having a particle size of 75 μm or more: 0.1%) quartz powder (3) fused spherical silica quartz powder having a specific surface area of 10 m ² / g and an average particle diameter of 1.0 μm (4) specific surface area of 1.0 m ² / G, spherical silica having an average particle size of 30 μm (coarse particles having a particle size of 75 μm or more: 0.1%) and a specific surface area of 3.2 m
² / g, crushed silica having an average particle size of 8 μm (coarse particles having a particle size of 75 μm or more: 0.1%) and the above quartz powder (3) were mixed in a ratio of 70: 2
Fused silica surface-treated with a mixture of 0:10 parts by weight and treated with 0.60% by weight of γ-glycidoxypropyltrimethoxysilane

From the results shown in Table 1, the composition according to the present invention has good fluidity, high glass transition temperature (Tg), excellent crack resistance (I and II) after moisture absorption soldering, strong adhesive strength, It is recognized that a cured product having a low water absorption is given.

[0064]

As described above, the epoxy resin composition of the present invention has good fluidity, low stress, low linear expansion coefficient, and low moisture absorption by using the above-mentioned components in combination. It is possible to obtain a cured product having a high glass transition temperature and good moisture resistance and mechanical strength. Therefore, a semiconductor device sealed with the cured product of the epoxy resin composition of the present invention is reliable. It has excellent properties.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which cracks have occurred in an SO package used in a crack resistance (II) test after moisture absorption soldering.

FIG. 2 is a perspective view showing a package used in an adhesion test.

[Description of Signs] 1 silicon chip 2 frame 3 sealing resin 4 crack

 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-258830 (JP, A) JP-A-2-189326 (JP, A) JP-A-63-227621 (JP, A) JP-A-4- 155939 (JP, A)

Claims (3)

(57) [Claims] (A) The following general formula (1): (B) an epoxy resin represented by the following general formula (2): An epoxy resin composition comprising: a curing agent mainly containing a triphenolalkane-type resin represented by the formula: (C) an inorganic filler. (A) The following general formula (1): (B) a substituted or unsubstituted novolak phenol resin and / or the following general formula (2): A curing agent containing a triphenol alkane resin as a main component, (C) an inorganic filler, and (D) a general formula (3) shown below. And an organic polymer represented by the following general formula (4): An epoxy resin composition comprising a block copolymer obtained by an addition reaction with an organopolysiloxane represented by the formula: 3. A semiconductor device sealed with a cured product of the epoxy resin composition according to claim 1.