Patent ID: 7170186

Claim:
A power semiconductor apparatus comprising: a circuit electrode; a laminated radiation member comprising a radiation plate and an insulation substrate bonded to an upper surface of said radiation plate, said circuit electrode being provided on an upper surface of said insulation substrate; a semiconductor chip bonded to said circuit electrode; and a metal wire electrically connected to said semiconductor chip and a metal wire electrically connected to said circuit electrode; wherein said semiconductor chip, said laminated radiation member and said circuit electrode are sealed with an insulating sealer; and wherein said radiation plate and said insulation substrate are bonded via a metal-based composite material layer present between said radiation plate and said insulation substrate, said metal-based composite material layer comprising a metal-based material, surface treated ceramic particles having a metal surface layer dispersed within said metal-based material, particles of at least one active metal selected from the group consisting of Ti, Hf, Nb, Ta and Zr dispersed within said metal-based material, and a reaction product between said metal-based material and said metal surface layer of said surface treated ceramic particles, said reaction product comprising a metal element of said metal-based material and a metal element of said metal surface layer of said surface treated ceramic particles, wherein said active metal particles are added to said surface treated ceramic particles before said surface treated ceramic particles are dispersed within said metal-based material, and wherein a pressure is applied to said surface treated ceramic particles to reduce the thickness and improve the packing rate of said surface treated ceramic particles before said surface treated ceramic particles are dispersed within said metal-based material.