Circuit substrate for mounting a semiconductor element.

摘要

A circuit substrate for mounting a semiconductor element comprises an aluminum-copper clad foil (8,9) laminated on a metallic base plate (1) by interposing an insulating layer (2), wherein the roughness in average of the surface in contact with the insulating layer of the aluminum-copper clad foil is in a range of from 0.5 mu m to 50 mu m.