JPH05136297A - Electronic part sealing resin composition and its curing matter - Google Patents

Abstract

PURPOSE:To acquire a resin composition of good adhesion with a lead frame and good crack resistance without damaging heat resistance by using specific epoxy resin. CONSTITUTION:An electronic part sealing resin composition which contains epoxy resin, curing agent, hardening accelerator and silica powder as essential elements expressed by a formula I (R1, R2, R3 are the same or different and a formula (a), a formula (b) a formula (c), a formula (d) or a formula (e), A is alkylene; cycloalkylene; halogen, cycloalkyle or alkylene which is displaced by aryl and X1 to X42 are hydrogen atom, alkylene group or halogen. (m) and (n) are an integer of 1 or more.). Such an epoxy resin composition does not damage heat resistance, realizes a curing matter of good adhesion and is useful for sealing resin of an electronic part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for encapsulating an electronic component, which is used for a resin for encapsulating an electronic component such as a semiconductor device and has excellent adhesiveness and crack resistance.

[0002]

2. Description of the Related Art Conventionally, a composition obtained by adding a phenol novolac resin as a curing agent to a novolac type epoxy resin has been widely used as a resin sealing material for electronic parts such as IC and LSI. This is because the epoxy resin composition has excellent mechanical properties, electrical properties, thermal properties and moldability. However, with the recent progress in the electronics field, semiconductor chips have been highly integrated and the chip size has increased. On the other hand, packages tend to be smaller and thinner. Therefore, cracking due to thermal shock,
During surface mounting, moisture in the package rapidly expanded, causing problems such as cracking. For this reason, while maintaining the conventional heat resistance, a material having excellent crack resistance and moisture resistance has been demanded. Resins with improved moisture resistance have been proposed, but these resins have problems with the adhesion to the lead frame, large penetration of moisture from the interface of the lead frame, and less reduction in moisture content in the entire package. .. In order to reduce the water content of the entire package, it is necessary to improve the adhesiveness between the resin and the lead frame and prevent the water entry from the interface of the lead frame.

[0003]

[PROBLEMS TO BE SOLVED BY THE INVENTION] To provide a resin composition having excellent adhesiveness to a lead frame and excellent crack resistance while maintaining the heat resistance of conventional resins.

[0004]

As a result of various studies on the above-mentioned problems, the present inventors have found that the use of a specific epoxy resin makes it possible to adhere to a lead frame and to prevent cracking without impairing heat resistance. It was found that an excellent resin composition was obtained, and the present invention was completed.

That is, the present invention provides (1) A) general formula (1)

[0006]

[Chemical 11]

(Wherein R ₁ and R ₂ and R ₃ are the same or different,

[0008]

[Chemical 12]

(B)

[Chemical 13]

(C)

[Chemical 14]

(D)

[Chemical 15]

Or (e)

[Chemical 16]

And A is alkylene; cycloalkylene; alkylene substituted with halogen, cycloalkyl or aryl;

[0014]

[Chemical 17] Or

[0015]

[Chemical 18] And X _{1 to} X ₄₂ are each independently hydrogen, an alkyl group or halogen. Moreover, m and n show an integer greater than or equal to 1. further

[0016]

[Chemical 19]

And

[Chemical 20]

And are arranged in an arbitrary order. An epoxy resin represented by the formula B) a curing agent C) a curing accelerator D) a silica powder as an essential component, a resin composition for electronic part encapsulation, (2) the electronic part according to item 1. A cured product of a resin composition for sealing is provided.

The epoxy resin used in the present invention is represented by the general formula (2).

[0020]

[Chemical 21]

Or the general formula (3)

[0022]

[Chemical formula 22]

(Wherein R ₁ , R ₂ , R ₃ and m and n have the same meanings as in the above-mentioned general formula (1)), the phenolic hydroxyl group and the anochol hydroxyl group and epichlorohydrin of the compound Reaction with dimethylsulfoxide or a quaternary ammonium salt or 1,3-dimethyl-2-imidazolidinone in the presence of an alkali metal hydroxide to adjust the amount of the alkali metal hydroxide used. it can. The reaction of the phenolic hydroxyl group and the alcoholic hydroxyl group of the compound represented by the general formula (3) with epichlorohydrin can be carried out by the above method or in the presence of a Lewis acid catalyst. A large amount of epichlorohydrin reacted with the hydroxyl group of chlorohydrin of the product, resulting in a very high hydrolyzable chlorine content and a low epoxy group content. This epoxy resin having a high content of hydrolyzable chlorine has an adverse effect on the properties of the cured product, and particularly deteriorates the electrical properties, and is not suitable for use in electronic materials.

As the epoxy resin represented by the general formula (1) used in the present invention, for example, R ₁ and R ₂ and R ₃ in the general formula (1) are represented by the above formula (a). Is for example

[0025]

[Chemical formula 23]

[0026]

[Chemical formula 24]

[0027]

[Chemical 25]

[0028]

[Chemical formula 26]

[0029]

[Chemical 27]

[0030]

[Chemical 28]

[0031]

[Chemical 29]

[0032]

[Chemical 30]

[0033]

[Chemical 31]

[0034]

[Chemical 32]

[0035]

[Chemical 33]

[0036]

[Chemical 34]

[0037]

[Chemical 35]

[0038]

[Chemical 36]

[0039]

[Chemical 37]

[0040]

[Chemical 38]

[0041]

[Chemical Formula 39]

As the one represented by the above formula (b), for example,

[0043]

[Chemical 40]

[0044]

[Chemical 41]

As the one represented by the formula (c), for example,

[0046]

[Chemical 42]

[0047]

[Chemical 43]

[0048]

[Chemical 44]

[0049]

[Chemical 45]

[0050]

[Chemical 46]

[0051]

[Chemical 47]

[0052]

[Chemical 48]

[0053]

[Chemical 49]

[0054]

[Chemical 50]

[0055]

[Chemical 51]

[0056]

[Chemical 52]

[0057]

[Chemical 53]

[0058]

[Chemical 54]

[0059]

[Chemical 55]

[0060]

[Chemical 56]

[0061]

[Chemical 57]

[0062]

[Chemical 58]

[0063]

[Chemical 59]

[0064]

[Chemical 60]

[0065]

[Chemical formula 61]

The expression (d) is, for example,

[0067]

[Chemical formula 62]

[0068]

[Chemical 63]

Examples of those represented by the above formula (e) include

[0070]

[Chemical 64]

[0071]

[Chemical 65]

However, the present invention is not limited to these. R ₁ in the general formula (1)
And R ₂ and R ₃ may include different ones.

The epoxy resin which is an essential component of the present invention is
It is represented by the general formula (1), m and n in the general formula (1) are each 1 or more, and m / (m + n) is preferably 0.10 to 0.80, more preferably 0.20 to 0. ．
70. m + n is preferably 2 to 13, more preferably 2 to 6. When m / (m + n) is less than 0. 10, the heat resistance is insufficient, which is not preferable. Also, m / (m
If + n) exceeds 0.80, the adhesiveness decreases, which is not preferable. When m + n exceeds 13, melt viscosity becomes high and handling becomes difficult, which is not preferable.

R ₁ , R ₂ and R ₃ in the general formula (1) are the same as those in the above formulas (c-3), (c-4) or (c-
A mixture of 3) and (c-4) is particularly preferable because it has excellent adhesiveness and heat resistance.

The epoxy resin used in the present invention can be used in combination with the epoxy resin represented by the general formula (1) and other epoxy resins used for sealing electronic parts. If the content of hydrolyzable chlorine in the epoxy resin represented by the general formula (1) is too large, reliability problems will occur when used for sealing electronic parts. The content of 0.15% or less is used.

As the curing agent, those having a small amount of impurities are preferable and those used for sealing electronic parts may be used. Phenols such as phenol novolac and orthocresol novolac, diaminodiphenylmethane, diaminodiphenyl sulfone and metaphenylenediamine. Amines, acid anhydrides such as phthalic anhydride, tetrahydrophthalic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid anhydride, and methylnadic acid anhydride; guanidines such as orthotolylbisguanidine and tetramethylguanidine; dicyandiamide Etc. can be used.

The amount of the curing agent used is not particularly limited, but is preferably 0.1 to 2.0 equivalents, more preferably 0.3 to 1.5 equivalents, based on the epoxy group.

As the curing accelerator, imidazoles such as 2-methylimidazole, 2-ethylimidazole and 2-phenylimidazole, benzyldimethylamine,
Examples include secondary amines such as 2.4.6-tris (dimethylamino) phenol, phosphine compounds such as triphenylphosphine, aluminum compounds, and titanium compounds.

The amount of the curing accelerator used is the epoxy resin 10
The amount is preferably 0.1 to 5.0 parts by weight, more preferably 0.3 to 3.0 parts by weight, based on 0 parts by weight.

The silica powder may be any one used in electronic applications, and preferably has a high purity.

The content of silica powder is preferably 20 to 90% by weight based on the resin composition. If it is 20% by weight or less, the reliability may be poor, and if it is 90% by weight or more, there may be a problem in moldability.

The resin composition for encapsulating electronic parts of the present invention contains the above-mentioned specific epoxy resin, curing agent, curing accelerator, and silica powder as essential components. It can be obtained by uniformly blending a flame retardant, a coloring agent, a coupling agent, a stress lowering agent and the like. The resin composition of the present invention can be made into a cured product by general preparation, molding and curing. As a general method of preparing a molding material, the essential components and other components as necessary,
It can be obtained by blending in a predetermined ratio, kneading at a temperature of 60 to 100 ° C. for usually 5 to 30 minutes by a hot roll or a kneader, then performing a mixing treatment, then cooling and pulverizing, and further forming a tablet if necessary. As a method for sealing electronic parts such as semiconductors using this molding material, low-pressure transfer molding is generally used, but injection molding, casting, etc. are also possible. In the low pressure transfer molding method, the molding pressure is 30 to 90 kg / cm ² , and the molding time is 10 to 120.
Second, a molding temperature of 150 to 190 ° C. is usually used. The encapsulating resin composition is usually further post-cured after molding. The post-curing condition is a post-curing temperature of 150 to
It is usually performed at 190 ° C. and a post-curing time of 3 to 8 hours.

[0083]

EXAMPLES The present invention will now be described in detail with reference to Examples and Comparative Examples. In the following, all parts are parts by weight unless otherwise specified.

Synthesis Example 1 In the bisphenol A type epoxy resin in which R ₁ and R ₂ and R ₃ in the general formula (2) are the above formula (c-3), an epoxy resin having an epoxy equivalent of 650 and a softening point of 81 ° C. (epoxy Resin (15)) (394 g, 1 equivalent of alcoholic hydroxyl group) was dissolved in epichlorohydrin (925 g, 10 mol) and dimethyl sulfoxide (462.5 g), and the mixture was stirred at 70 ° C. to give 98.5% NaOH (13.3 g).
(0.33 mol) was added over 100 minutes. After the addition, the reaction was further performed at 70 ° C. for 3 hours. Water after reaction 250
g was added and washed with water. After oil-water separation, most of dimethylsulfoxide and excess unreacted epichlorohydrin were distilled and recovered from the oil layer under reduced pressure, and a reaction product containing a by-product salt and dimethylsulfoxide was extracted with methyl isobutyl ketone 750.
g, and add 10 g of 30% NaOH to 70
The reaction was carried out at 0 ° C for 1 hour. After the reaction was completed, the product was washed twice with 200 g of water. After separation of oil and water, methyl isobutyl ketone was distilled and recovered from the oil layer to obtain an epoxy equivalent of 444 and a softening point of 7
350 g of 9 degreeC epoxy resin (1) was obtained. The obtained epoxy resin (1) has m + n = 3.3, m / (m + n) =
It was 0.30.

Synthesis Example 2 Epoxy equivalent 305 and softening point 73 in the same manner as in Synthesis Example 1 except that the epoxy resin (15) was used and the amount of 98.5% NaOH used was 31.6 g (0.78 mol). 365 g of epoxy resin (2) having a temperature of 0 ° C. was obtained. The obtained epoxy resin (2) has m + n = 3.3, m / (m + n) = 0.70.
Met.

Synthesis Example 3 Epoxy equivalent 280 and softening point 64 in the same manner as in Synthesis Example 1 except that the epoxy resin (15) was used and the amount of 98.5% NaOH used was 60.9 g (1.50 mol). 370 g of an epoxy resin (16) having a temperature of 0 ° C. was obtained. The obtained epoxy resin (16) had m + n = 3.3, m / (m + n) = 1.
It was 00.

Synthesis Example 4 In the bisphenol A type epoxy resin in which R ₁ and R ₂ and R ₃ in the general formula (2) are the above-mentioned formula (c-3), 350 g of an epoxy resin having an epoxy equivalent of 910 and a softening point of 101 ° C. (1 equivalent of alcoholic hydroxyl group)
350 g of epoxy resin (3) having an epoxy equivalent of 429 and a softening point of 90 ° C. was obtained in the same manner as in Synthesis Example 1, except that 8.5% NaOH was changed to 25.7 g (0.63 mol). The obtained epoxy resin (3) = m + n is 5.2, m / (m +
n) = 0.50.

Synthesis Example 5 Instead of the epoxy resin (15), R ₁ and R ₂ and R ₃ in the general formula (2) are represented by the above formula (c-3) and the above formula (c).
-4), which is a mixture with 580 g of an epoxy resin having an epoxy equivalent of 725, a softening point of 86 ° C. and a bromine content of 27.7%.
(1 equivalent of alcoholic hydroxyl group) is used, 98.5% N
Epoxy equivalent of 474, softening point 80 ° C., in the same manner as in Synthesis Example 1 except that aOH was changed to 20.3 g (0.5 mol).
562 g of an epoxy resin (4) having a bromine content of 26.5% was obtained. The obtained epoxy resin (4) has m + n = 2.5,
It was m / (m + n) = 0.48.

Synthesis Example 6 Instead of the epoxy resin (15), R ₁ and R ₂ and R ₃ in the general formula (2) are the above formula (c-4), epoxy equivalent 1018, softening point 133 ° C., bromine content. Amount 51.
885 g of 9% epoxy resin (1 equivalent of alcoholic hydroxyl group) was used, and 22.3 g (0.
55 mol), in the same manner as in Example 1 except that the epoxy equivalent is 657, the softening point is 125 ° C., and the bromine content is 50.2%.
870 g of the epoxy resin (5) was obtained. The obtained epoxy resin (5) had m + n = 2.3, m / (m + n) = 0.
It was 52.

Synthesis Example 7 R ₁ and R ₂ and R ₃ in the general formula (2) are the above formula (a-1), the epoxy equivalent is 284, the softening point is 56 ° C.,
270 g of epoxy resin (1 equivalent of alcoholic hydroxyl group)
Was dissolved in 925 g (10 mol) of epichlorohydrin, 5 g of tetramethylammonium chloride was added at 70 ° C. with stirring, and then 26.4% of 98.5% NaOH was added.
g (0.65 mol) was added over 100 minutes. After the addition, the reaction was further performed at 70 ° C. for 3 hours. After the reaction, water 25
0 g was added and washed with water. After separation of oil and water, excess unreacted epichlorohydrin was recovered by distillation from the oil layer, and the reaction product was dissolved in 750 g of methyl isobutyl ketone.
10% (0.075 mol) of 0% NaOH was added and the mixture was reacted at 70 ° C. for 1 hour. After the reaction was completed, the product was washed twice with 200 g of water. After separating the oil and water, methyl isobutyl ketone was distilled and recovered from the oil layer to obtain 250 g of a semi-solid epoxy resin (6) having an epoxy equivalent of 206. The obtained epoxy resin (6) had m + n = 2.1 and m / (m + n) = 0.52.

Synthesis Example 8 As the epoxy resin, R ₁ and R ₂ in the general formula (2) are used.
And R ₃ is the above formula (d-1), and has an epoxy equivalent of 38
4, 305 g of an epoxy resin (7) having an epoxy equivalent of 261 and a softening point of 71 ° C. was obtained in the same manner as in Synthesis Example 7 except that 334 g of an epoxy resin having a softening point of 76 ° C. (1 equivalent of an alcoholic hydroxyl group) was used. .. The obtained epoxy resin (7) had m + n = 2.3, m / (m + n) = 0.52.

Synthesis Example 9 After dissolving 242 g (1 mol) of 4,4'-bishydroxy-3,3 ', 5,5'-tetramethylbiphenyl in 61 g (0.066 mol) of epichlorohydrin and 370 g of dimethyl sulfoxide. , 98.5% at 70 ° C with stirring
29.5 g (0.73 mol) of NaOH were added over 30 minutes. After the addition, the mixture was reacted at 70 ° C. for 1 hour and further at 90 ° C. for 5 hours. After the reaction, methyl isobutyl ketone 800
g and 300 g of water were added and washed with water. After oil-water separation, methyl isobutyl ketone and dimethyl sulfoxide were distilled and recovered from the oil layer under reduced pressure to obtain R ₁ in the general formula (3).
And 278 g of compound (1) in which R ₂ and R ₃ are the above formula (b-2) were obtained. 224 g of the obtained compound (1)
(Phenolic hydroxyl group 0.5 equivalent, alcoholic hydroxyl group 0.55 equivalent) is used and 98.5% NaOH 26.4
Synthesis Example 7 except that g was changed to 34.9 g (0.86 mol)
In the same manner as above, 250 g of an epoxy resin (8) having an epoxy equivalent of 350 and a softening point of 89 ° C. was obtained. The obtained epoxy resin (8) has m + n = 2.2, m / (m + n) = 0.5.
It was 0.

Synthesis Example 10 R ₁ and R ₂ in the general formula (2) are used as an epoxy resin.
And R ₃ is the above formula (e-1) and has an epoxy equivalent of 65.
8, except that 627 g of an epoxy resin having a softening point of 165 ° C. (1 equivalent of alcoholic hydroxyl group) was used, and 462.5 g of 1,3-dimethyl-2-methylimidazolidinone was used instead of 5 g of tetramethylammonium chloride. Epoxy equivalent of 444 and softening point of 15 in the same manner as in Example 7.
630 g of epoxy resin (9) at 1 ° C. was obtained. The obtained epoxy resin (9) has m + n = 2.0, m / (m + n) =
It was 0.52.

Examples 1 to 3 and Comparative Examples 1 and 2 The compounding ratios shown in Table 1 (numerical values indicate parts by weight) were kneaded with a mixing roll and then pulverized to give test samples.
Test pieces were prepared by the following methods. The glass transition point (Tg) was 5 at 175 ° C x 90sec on the transfer molding machine after turning the crushed product into tablets with a tablet machine.
After making a test piece of × 5 × 15 mm, 160 ° C for 2 hours +
Post-curing was performed at 180 ° C. for 6 hours. The adhesion test is 25.
4 x 100 x 0.2 mm Cr-Ni alloy (42 alloy)
The pulverized sample is melt-coated on 150 ° C. and pressure-bonded at a pressure of 10 kg / cm ² , and then clamped in a clamp at 160 ° C. for 2 hours + 1
Post-curing was performed at 80 ° C. for 6 hours. (Adhesive area 25.4 x
Compounds other than the resins (1) to (9) and (15) and (16) are shown below. EOCN-1020: Cresol novolac epoxy resin (Nippon Kayaku) [epoxy equivalent 200, softening point 65 ° C] BREN: brominated phenol novolac epoxy (Nippon Kayaku) [epoxy equivalent 280, softening point 83 ° C, bromine-containing 35.5] %] PN: phenol novolac (Nippon Kayaku) [hydroxyl group equivalent 105, softening point 83 ° C] RD-8: fused silica (Tatsumori) KBM-403: silane coupling agent (Shin-Etsu Chemical) TPP: triphenylphosphine ( Takashin Chemical)

Table 1 shows the results of measuring Tg and adhesive strength by the following methods. The thermal expansion was measured at a temperature rising rate of 2 ° C./min by Tg: TMA (vacuum engineering) and determined from the inflection point of the thermal expansion curve. Adhesion test: Measured by tensile shearing after removing the resin composition protruding from the adhesion part. (Crosshead speed 3mm / min)

[0096]

[Table 1]

Examples 4 and 5 and Comparative Example 3 Resins (4) and (5) were used in place of the brominated phenol novolac used as the flame retardant, and the composition shown in Table 2 was used to obtain the same composition as in Example 1. A sample was prepared by the method and measured.
The measurement results are shown in Table 2.

[0098]

[Table 2]

Examples 6 to 9 and Comparative Example 3 Samples having the compositions shown in Table 3 were prepared and measured in the same manner as in Example 1. The measurement results are shown in Table 3.

[0100]

[Table 3]

In Table 1, Comparative Example 1 is too low in heat resistance, and Comparative Example 2 is too low in adhesive strength to be suitable for sealing electronic parts. On the other hand, Examples 1, 2 and 3 have heat resistance and adhesive strength and are suitable for sealing electronic components. In Table 2, the heat resistance of Examples 4 and 5 is almost the same as that of Comparative Example 3, but the adhesiveness is improved. Also in Table 3, Examples 6, 7, 8 and 9 show less decrease in heat resistance than Comparative Example 3 and significant improvement in adhesiveness is observed. As seen in the examples, the epoxy resin composition of the present invention does not impair the heat resistance,
A cured product having excellent adhesiveness is obtained, which is extremely useful as a resin for sealing electronic parts.

[0102]

The resin composition for sealing electronic parts of the present invention is
A cured product having excellent adhesiveness can be obtained without impairing heat resistance.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location C08L 63/00 NKX 8830-4J

Claims (2)

[Claims] 1. A) General formula (1): (In the formula, R ₁ and R ₂ and R ₃ are the same or different, and are represented by the formula (a) (B) [Chemical Formula 3] (C) [Chemical formula 4] (D) embedded image Or (e) And A is alkylene; cycloalkylene; alkylene substituted with halogen, cycloalkyl or aryl; Or And X _{1 to} X ₄₂ are each independently a hydrogen atom, an alkyl group or a halogen. Further, m and n are integers of 1 or more. Furthermore, And [Chemical 10] And are arranged in any order. An epoxy resin represented by the formula B) a curing agent C) a curing accelerator D) a silica powder as an essential component. 2. A cured product of the resin composition for encapsulating an electronic component according to claim 1.