PACKAGE FOR HOUSING SEMICONDUCTOR ELEMENT

PROBLEM TO BE SOLVED: To solve the problem that it is difficult for the package for housing a semiconductor element comprising a conventional heatsink base to reliably disperse heat since the thermal conductivity of the heatsink base is low. SOLUTION: The package for housing a semiconductor element comprises a heatsink base 3 provided with a placement part on which a semiconductor element 4 is placed, an insulating frame 1 fitted to the upper surface, and a lid 2 fitted to the upper surface of the insulating frame 1. The heatsink base 3 comprises a composite material layer 3a in which the porous body of tungsten or molybdenum is impregnated with copper and a copper layer 3b formed on its upper and lower surfaces. 30 μm