CURABLE RESIN COMPOSITION, CURED PRODUCT OBTAINED FROM THE SAME, METHOD FOR HARDENING THE SAME, AND SEMICONDUCTOR DEVICE

Abstract

There are provided a curable resin composition capable of having a rapid curing property and forming a cured product with an excellent property such as a high heat resistance, a cured product obtained from the curable resin composition, and a method for hardening the curable resin composition. There is further provided a semiconductor device using the curable resin composition as a sealant. The curable resin composition contains (A) a polyfunctional benzoxazine compound having at least two benzoxazine rings, (B) a polyfunctional epoxy compound having at least one norbornane structure and at least two epoxy groups, (C) a curing agent, and (D) a phosphorus-containing curing accelerator, and optionally further contains (E) an inorganic filler. The semiconductor device contains a cured product obtained by hardening the curable resin composition containing the components (A) to (E), and further contains a semiconductor element placed in the cured product.

Claims

1. A curable resin composition comprising (A) a polyfunctional benzoxazine compound having at least two benzoxazine rings, (B) a polyfunctional epoxy compound having at least one norbornane structure and at least two epoxy groups, (C) a curing agent, and (D) a phosphorus-containing curing accelerator, wherein the polyfunctional benzoxazine compound of (A) is a first benzoxazine compound or a second benzoxazine compound, the first benzoxazine compound is a compound having at least two benzoxazine ring structures represented by the following formula (1): ##STR00027## wherein R is an acyclic alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, and the aryl group may have a substituent of a halogen atom or an acyclic alkyl group having 1 to 12 carbon atoms, the benzene rings in the two benzoxazine ring structures being bonded to each other, and the second benzoxazine compound is represented by the following formula (2): ##STR00028## wherein L is a divalent organic group having 1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms.

2. The curable resin composition according to claim 1, further comprising (E) an inorganic filler.

3. The curable resin composition according to claim 1, wherein the curing agent of (C) is at least one selected from the group consisting of imidazole compounds, aromatic amine compounds, and polyfunctional phenol compounds.

4. A cured product obtained by hardening the curable resin composition according to any one of claims 1.

5. A semiconductor device comprising a cured product obtained by hardening the curable resin composition according to claim 2 and a semiconductor element placed in the cured product.

6. A method for hardening a curable resin composition comprising the steps of: heating and mixing (A) a polyfunctional benzoxazine compound having at least two benzoxazine rings, (B) a polyfunctional epoxy compound having at least one norbornane structure and at least two epoxy groups, (C) a curing agent, (D) a phosphorus-containing curing accelerator, and (E) an inorganic filler in a mixing apparatus to obtain a mixture; processing the mixture into a powder, a pellet, or a granule of a curable resin composition; and heating the curable resin composition at a temperature of 180 C. to 300 C. for a period of 20 seconds to 1 hour to harden the curable resin composition, wherein the polyfunctional benzoxazine compound of (A) is a first benzoxazine compound or a second benzoxazine compound, the first benzoxazine compound is a compound having at least two benzoxazine ring structures represented by the following formula (1): ##STR00029## wherein R is an acyclic alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, and the aryl group may have a substituent of a halogen atom or an acyclic alkyl group having 1 to 12 carbon atoms, the benzene rings in the two benzoxazine ring structures being bonded to each other, and the second benzoxazine compound is represented by the following formula (2): ##STR00030## wherein L is a divalent organic group having 1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms.

7. The curable resin composition according to claim 2, wherein the curing agent of (C) is at least one selected from the group consisting of imidazole compounds, aromatic amine compounds, and polyfunctional phenol compounds.

8. A cured product obtained by hardening the curable resin composition according to claim 2.

9. A cured product obtained by hardening the curable resin composition according to claim 3.

Description

EXAMPLES

[0066] The present invention will be described more specifically below with reference to Examples and Comparative Examples without intention of restricting the scope of the invention.

<Component (A); Polyfunctional benzoxazine compound>

[0067] The following compounds (A1) and (A2) were each used as the component (A).

(A1); Bisphenol F-aniline type (F-a type) benzoxazine compound of the following formula (1-1) available from Shikoku Chemicals Corporation.

##STR00017##

(A2); Phenol-diaminodiphenylmethane type (P-d type) benzoxazine compound of the following formula (2-1) available from Shikoku Chemicals Corporation.

##STR00018##

<Component (B) or (BC); Polyfunctional epoxy compound>

[0068] The following compounds (B1) to (B3) were each used as the component (B).

(B1); Compound (5-1)

[0069] The compound (a) shown in the above formula (6) was synthesized by a method described in Shoichi Tsuchida, et. al., Diels-Alder Reaction between Butadiene and Cyclopentadiene, Determination of Trimers, Journal of The Japan Petroleum Institute, 1972, Volume 15, Issue 3, Pages 189-192. 15.9 L of chloroform and 1.6 kg of the compound (a) were introduced into a reaction vessel, and 4.5 kg of meta-chloroperbenzoic acid was added dropwise thereto while stirring at 0 C. The obtained mixture was heated to the room temperature, and the reaction shown in the formula (6) was carried out for 12 hours. A by-product of meta-chlorobenzoic acid was removed from the resultant mixture by filtration. The filtrate was washed with a 1-N aqueous sodium hydroxide solution three times, and was further washed with a saturated sodium chloride solution. The organic layer was dried over magnesium sulfate, the magnesium sulfate was removed by filtration, and the filtrate was concentrated to obtain a crude product. 2 kg of toluene was added to the crude product, and the crude product was dissolved at the room temperature. 6 kg of heptane was added dropwise to the solution to conduct crystallization, and the resultant was aged at 5 C. for 1 hour. The crystallized product was isolated by filtration, washed with hexane, and dried under a reduced pressure at 35 C. for 24 hours, to obtain 1.4 kg of a white solid of the following compound (5-1).

##STR00019##

(B2); Compound (5-2) (tricyclopentadiene diepoxide)

[0070] The compound (b) shown in the above formula (7) was synthesized in the same manner as the compound (a) by a method described in the above reference. 59.2 kg of chloroform and 4.0 kg of the compound (b) were introduced into a reaction vessel, and 10.6 kg of meta-chloroperbenzoic acid was added dropwise thereto while stirring at 10 C. The obtained mixture was heated to the room temperature, and the reaction shown in the formula (7) was carried out for 12 hours. A by-product of meta-chlorobenzoic acid was removed from the resultant mixture by filtration. The filtrate was washed with 42.0 kg of a 5% aqueous sodium sulfite solution. The organic layer was washed with 41.6 kg of a 1-N aqueous sodium hydroxide solution four times, and further washed with 48.0 kg of a saturated sodium chloride solution. The organic layer was dried over magnesium sulfate, the magnesium sulfate was removed by filtration, and the filtrate was concentrated to obtain 5.1 kg of a crude product. 3.5 kg of toluene was added to the crude product, and the crude product was dissolved at the room temperature. 13.7 kg of heptane was added dropwise to the solution to conduct crystallization, and the resultant was aged at 5 C. for 1 hour. The crystallized product was isolated by filtration, washed with heptane, and dried under a reduced pressure at 35 C. for 12 hours, to obtain 2.8 kg of a white solid of the following compound (5-2).

##STR00020##

(B3); Compound (5-4) (dicyclopentadiene diepoxide)

[0071] 10 kg of dicyclopentadiene, 68 kg of sodium bicarbonate, 100 L of acetone, and 130 L of an ion-exchange water were introduced into a reaction vessel, and the resultant reaction liquid was cooled to a temperature of 10 C. or lower. 84 kg of Oxone was added slowly to the reaction liquid while cooling to maintain the reaction liquid at a temperature of 30 C. or lower, and the reaction liquid was stirred to carry out a reaction for 10 hours. Extraction with 100 L of ethyl acetate was carried out two times, and the organic layer was collected. Then, the organic layer was washed with 100 L of a mixed aqueous solution (containing 20% by weight of sodium chloride and 20% by weight of sodium thiosulfate), and was further washed with 100 L of an ion-exchange water two times. The washed organic layer was dried over magnesium sulfate, the magnesium sulfate was removed by filtration, and organic solvents were distilled away from the filtrate, to obtain 11 kg of a white solid of the following compound (5-4).

##STR00021##

[0072] The following two components (BC1) and (BC2), which had no norbornane structures, were each used as (BC) a polyfunctional epoxy compound for Comparative Examples.

(BC1); Polyfunctional epoxy compound of the following formula (9), YX-4000H available from Mitsubishi Chemical Corporation.

##STR00022##

(BC2); Polyfunctional epoxy compound of the following formula (10), NC3000 available from Nippon Kayaku Co., Ltd.

##STR00023##

<Component (C); Curing Agent>

[0073] The following compounds (C1) to (C3) were each used as the component (C).

(C1); Bis(4-hydroxyphenyl) sulfide of the following formula (11), TDP available from Tokyo Chemical Industry Co., Ltd.

##STR00024##

(C2); 4,4-Diaminodiphenyl sulfide of the following formula (12), DDS available from Tokyo Chemical Industry Co., Ltd.

##STR00025##

(C3); Bisphenol F of the following formula (13), BisF available from Honshu Chemical Industry Co., Ltd.

##STR00026##

<Component (D); Phosphorus-Containing Curing Accelerator>

[0074] The following compounds (D1) to (D3) were each used as the component (D).

(D1); Triphenylphosphine TPP available from Hokko Chemical Industry Co., Ltd.
(D2); Tetraphenylphosphonium tetraphenylborate TPP-K available from Hokko Chemical Industry Co., Ltd.
(D3); Tetraphenylphosphonium tetra-p-tolyl borate TPP-MK available from Hokko Chemical Industry Co., Ltd.

<Component (E); Inorganic Filler>

[0075] A molten spherical silica having an average grain diameter D50 of 22 m, FB-820 available from Denka Company Limited, was used as the component (E). This is hereinafter referred to as (E).

<Other Components>

[0076] A carnauba wax available from Clariant Japan K. K. was used as a mold release agent, and a carbon black MA600 available from Mitsubishi Chemical Corporation was used as a colorant. Although the carbon black was used as a colorant, it acted also as the component (E).

Example 1

[0077] A composition and a cured product of Example 1 were prepared, the gel time was measured to evaluate the curing speed, and the glass-transition temperature was measured to evaluate the heat resistance, as described below.

[0078] The components (A1), (B1), (C1), (D1), and (E), the carnauba wax, and the carbon black were kneaded at the mixing ratios shown in Table 1 under the atmospheric pressure for 10 minutes by using a hot roll kneader having two rolls having surface temperatures of 90 C. and 100 C., and then were cooled to the room temperature to obtain a mixture. The mixture was pulverized into a powder by Mini Speed Mill MS-09 available from Labonect K. K. to obtain the composition, so that the composition could be easily introduced into a mold.

<Gel Time>

[0079] The hardening (curing) property of the composition of the present invention can be evaluated based on the measurement of the gel time. The gel time is not particularly limited, and is preferably at least 20 seconds and at most 120 seconds, more preferably at least 30 seconds and at most 100 seconds. In Examples, according to Gel Time Method B (plate method) of JIS K 6910 (2007), a composition was placed on a hot plate having a controlled temperature of 200 C., the composition was stirred by a spatula, and the time (second) elapsed until the composition lost its flowability (until it became impossible to stir the composition due to progress of the thermal hardening reaction) was measured as the gel time. When the composition exhibits a shorter gel time, the composition has a higher curing speed and a more excellent rapid curing property. The results are shown in Table 1.

<Glass-Transition Temperature; Tg>

[0080] The heat resistance of the cured product of the present invention can be evaluated based on the measurement of the glass-transition temperature. The glass-transition temperature is not particularly limited as long as the advantageous effects of the present invention are achieved. The glass-transition temperature is preferably 200 C. or higher, more preferably 210 C. or higher, further preferably 220 C. or higher. The glass-transition temperature can be measured by differential scanning calorimetry (DSC). The glass-transition temperature can be easily measured by using a commercially-available differential scanning calorimeter (e.g., available from Hitachi High-Tech Science Corporation). In Examples, a prepared composition was hardened in a transfer molding apparatus under conditions of a mold temperature of 200 C., an injection pressure of 4 MPa, and a hardening time of 6 minutes, and was further heated at 240 C. for 4 hours in an oven in a post-hardening treatment, to prepare a cured product having a height of 3 mm, a width of 3 mm, and a length of 15 mm. The cured product was cut into a shape having a height of 3 mm, a width of 3 mm, and a length of 2 mm to obtain a test sample. The Tg of the test sample was measured by the DSC under the following conditions. The results are shown in Table 1.

Apparatus: X-DSC-7000 (available from Hitachi High-Tech Science Corporation)
Measurement conditions: N.sub.2 flow rate of 20 mL/minute and heating rate of 20 C/minute

Examples 2 to 8

[0081] Compositions of Examples 2 to 8 were produced in the same manner as Example 1 except that the mass ratios of the components were changed as shown in Table 1 respectively. The gel time and Tg of each composition were measured in the same manner as

[0082] Example 1. The results are shown in Table 1.

Comparative Examples 1 to 4

[0083] Compositions of Comparative Examples 1 to 4 were produced in the same manner as Example 1 except that the mass ratios of the components were changed as shown in Table 2 respectively. The gel time and Tg of each composition were measured in the same manner as Example 1. The results are shown in Table 2.

TABLE-US-00001 TABLE 1 Examples 1 2 3 4 5 6 7 8 Component Polyfunctional (A1) 7.5 [parts by mass] benzoxazine (A2) 7.5 7.5 7.5 7.5 7.5 7.5 7.5 compound Polyfunctional (B1) 4.3 4.3 4.3 4.3 4.3 4.3 epoxy compound (B2) 4.3 (B3) 4.3 Curing agent (C1) 2.1 2.1 2.1 2.1 2.1 2.1 (C2) 2.1 (C3) 2.1 Phosphorus- (D1) 0.5 0.5 0.5 0.5 0.5 0.5 containing curing (D2) 0.5 accelerator (D3) 0.5 Inorganic filler (E) 85 85 85 85 85 85 85 85 Carnauba wax 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 (mold release agent) Carbon black (colorant) 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Property Gel time [seconds] 63 46 49 47 73 53 50 49 evaluation Tg [ C.] 233 257 261 260 235 251 248 223

TABLE-US-00002 TABLE 2 Comparative Examples 1 2 3 4 Component Polyfunctional (A1) [parts by mass] benzoxazine (A2) 7.7 7.5 7.5 8.8 compound Polyfunctional (B1) 4.5 5.1 epoxy compound (BC1) 4.3 (BC2) 4.3 Curing agent (C1) 2.1 2.1 2.1 (C2) (C3) Phosphorus- (D1) 0.5 0.5 0.5 containing curing (D2) accelerator (D3) Inorganic filler (E) 85 85 85 85 Carnauba wax 0.3 0.3 0.3 0.3 (mold release agent) Carbon black (colorant) 0.3 0.3 0.3 0.3 Property Gel time [seconds] 145 55 54 112 evaluation Tg [ C.] 243 158 153 214

[0084] In Examples, the curable resin compositions exhibited gel times of 100 seconds or less, and the cured products had Tg's of 200 C. or higher. Thus, in Examples, both of the excellent rapid curing property and the high heat resistance were achieved. In contrast, in Comparative Examples 1 and 4, although the cured products had relatively good heat resistances, the compositions exhibited long gel times and low curing speeds. Furthermore, in Comparative Examples 2 and 3, although the compositions exhibited relatively good rapid curing properties, the cured products had low Tg and low heat resistances. It is clear from the results that the curable resin composition according to an embodiment of the present invention is capable of achieving both of the excellent rapid curing property and the high heat resistance.