Heat-radiating substrate

Abstract

A heat-radiating substrate with a high insulation-withstand voltage and an excellent heat-radiating property is provided. The heat-radiating substrate includes: a metal base material; a metal thin layer formed over the metal base material and having a hardness higher than a hardness of the metal base material; and a ceramic layer over the metal thin layer. Alternatively, the heat-radiating substrate includes, instead of the metal thin layer, a hardened layer serving as a surface layer of the metal base material and having a hardness higher than the hardness of the metal base material. The metal thin layer and the hardened layer are able to enhance compressive stress or prevent release of the compressive stress generated in the ceramic layer by a mechanical impact applied to the ceramic layer.

Dependencies are inferred from the claim text.