Patent ID: 8071187

Claim:
A package for mounting a semiconductor device, the package comprising a metallized ceramics substrate comprising: a sintered ceramics substrate; a first conductive layer of which surface roughness is 0.85 Î¼m or less comprising tungsten and/or molybdenum and being formed on said sintered ceramics substrate; a sintered ceramics layer formed on said first conductive layer; and a second conductive layer of which surface roughness is 1.05 Î¼m or more comprising tungsten and/or molybdenum and being formed on said sintered ceramics layer, wherein a semiconductor device mounting portion is provided on said first conductive layer; said sintered ceramics layer and said second conductive layer are configured to surround said semiconductor device mounting portion so as to form a cavity portion for housing a semiconductor device; the semiconductor device which should be mounted is sealed by connecting a lid member having a metal part to the second conductive layer through the metal part; and the package has airtightness of 4.9Ã—10 âˆ’9 PaÂ·m 3 /s or less when the semiconductor device is sealed.