Patent ID: 7470983

Claim:
A semiconductor device comprising: a semiconductor element having a first coefficient of thermal expansion; a first metal plate bonded to one side of the semiconductor element; an intermediate layer bonded to one side of the first metal plate remote from the semiconductor element, the intermediate layer being made of a carbon-copper composite material; a second metal plate bonded to one side of the intermediate layer remote from the first metal plate; an insulating member bonded to one side of the second metal plate remote from the intermediate layer; and a third metal plate bonded to one side of the insulating member remote from the second metal plate, the third metal plate having a thickness substantially equal to that of the second metal plate; and, a heat sink having a second coefficient of thermal expansion, said second coefficient of thermal expansion being different than said first coefficient of thermal expansion; wherein the intermediate layer absorbs and moderates thermal stress resulting from said first coefficient of thermal expansion being different than said second coefficient of thermal expansion, and wherein the first, second and third metal plates are made of a same material.