COPPER BASE MATERIAL WITH ADHESIVE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device having excellent reliability by improving adhesive properties of a base material to molding resin. SOLUTION: This copper base material is constituted to form first polyimide resin to become an insulating layer on a copper foil and a second polyimide layer functioning as adhesive in contact with the resin. In this case, thermal expansion coefficient of the first polyimide resin is 10 to 35ppm/ deg.C and the thickness of the second polyimide resin layer is thinner than that of the first polyimide resin layer and 3μm or more. Thus, generation of a stress to heat at an interface of the molding resin is reduced to obtain excellent adhesive reliability with the resin.