The effect of electron beam irradiation on insulating characteristics of molding compound for power semiconductor modules

The high temperature-low expansion type epoxy resin used for molding material of power semiconductor elements is irradiated with an electron beam. It is found that the insulating characteristics of the molding material varied with electron beam irradiation conditions. The insulating characteristics of the molding material, such as dielectric breakdown voltage and volume resistivity, are investigated as a function of electron beam dose. As a result, the specimen which is irradiated with 4 Mrad has exhibited a high breakdown voltage and volume resistivity.