PURPOSE: To make the insulating property, heat radiating property, coefficient of thermal expansion of a cap for semiconductor elements to match those of semiconductor elements so that the cap cannot be damaged by cracking, strains, etc., by coating at least one surface of the base material of the cap with a polycrystalline diamond layer.
CONSTITUTION: At least one surface of the title one-body type cap 1 made of 42-alloy, kovar Mo, W, CuW, CuMo, Si3N4, SiC, mullite, AlN, BN, Al2O3, single-crystal silicon, and polycrystalline silicon is coated with a polycrystalline diamond layer. As a result, a high insulating and heat radiating properties can be easily obtained. In case the cap is joined to a semiconductor element by soldering, the degree of matching of the coefficient of thermal expansion of the cap to that of the element can be improved and the occurrence of strains or cracks at the boundary between the cap and element can be prevented by coating the joining surface of the cap with polycrystalline diamond.
UETSUKI YOSHIO
OTSUKA AKIRA
