Abstract: An epoxy resin composition which can be used as a semiconductor encapsulating resin and in which the improvement of flame retardancy can be attained by suitably adapting a crosslinked structure itself of a cured article without using any flame retardant material and without particularly highly filling an inorganic filler. The epoxy resin composition includes an epoxy resin (A), a phenolic resin (B), an inorganic filler (C) and a curing accelerator (D), wherein a flexural modulus E (kgf/mm2) at 240±20% C of a cured article obtained by curing the composition is a value satisfying 0.015 W+4.1?E?0.27 W+21.8 in the case of 30?W<60, or a value satisfying 0.30 W?13?E?3.7 W?184 in the case of 60?W?95 wherein W (wt %) is a content of the inorganic filler (C) in the cured article. The cured article of this composition forms a foamed layer during thermal decomposition or at ignition to exert flame retardancy.

Abstract: An epoxy resin composition which can be used as a semiconductor encapsulating resin and in which the improvement of flame retardancy can be attained by suitably adapting a crosslinked structure itself of a cured article without using any flame retardant material and without particularly highly filling an inorganic filler. The epoxy resin composition includes an epoxy resin (A), a phenolic resin (B), an inorganic filler (C) and a curing accelerator (D), wherein a flexural modulus E (kgf/mm2) at 240±20% C of a cured article obtained by curing the composition is a value satisfying 0.015 W+4.1?E?0.27 W+21.8 in the case of 30?W<60, or a value satisfying 0.30 W?13?E?3.7 W?184 in the case of 60?W?95 wherein W (wt %) is a content of the inorganic filler (C) in the cured article. The cured article of this composition forms a foamed layer during thermal decomposition or at ignition to exert flame retardancy.

Abstract: An epoxy resin composition which can be used as a semiconductor encapsulating resin and in which the improvement of flame retardancy can be attained by suitably adapting a crosslinked structure itself of a cured article without using any flame retardant material and without particularly highly filling an inorganic filler. The epoxy resin composition includes an epoxy resin (A), a phenolic resin (B), an inorganic filler (C) and a curing accelerator (D), wherein a flexural modulus E (kgf/mm2) at 240±20% C of a cured article obtained by curing the composition is a value satisfying 0.015 W+4.1?E?0.27 W+21.8 in the case of 30?W<60, or a value satisfying 0.30 W?13?E?3.7 W?184 in the case of 60?W?95 wherein W (wt %) is a content of the inorganic filler (C) in the cured article. The cured article of this composition forms a foamed layer during thermal decomposition or at ignition to exert flame retardancy.

Abstract: An epoxy resin composition for encapsulation of semiconductors which contains substantially no halogen-based flame retarding agents or antimony compounds having properties of moldability, flame retardance, high-temperature storage characteristics, reliability for moisture resistance, and solder cracking resistance. The epoxy resin composition for encapsulating semiconductors contains (A) an epoxy resin, (B) a phenolic resin, (C) a curing accelerator, (D) an inorganic filler and (E) a phosphazene compound as essential components, the total weight of phosphate ion and phosphite ion contained in the phosphazene compound being not more than 500 ppm. Further, the epoxy resin composition may optionally contain a flame-retarding assistant or an ion scavenger.

Abstract: The present invention provides an epoxy resin composition for encapsulation of semiconductors which contains substantially neither halogen-based flame retarding agents nor antimony compounds and is excellent in moldability, flame retardance, high-temperature storage characteristics, reliability for moisture resistance, and solder cracking resistance. That is, the present invention is an epoxy resin composition for encapsulating semiconductors which contains (A) an epoxy resin, (B) a phenolic resin, (C) a curing accelerator, (D) an inorganic filler and (E) a phosphazene compound as essential components, the total weight of phosphate ion and phosphite ion contained in the phosphazene compound being not more than 500 ppm. Further, the epoxy resin composition may optionally contain a flame-retarding assistant or an ion scavenger.