A semiconductor device including a die pad having a front surface made of Cu; a semiconductor chip disposed so as to be opposed to the front surface of the die pad; a bonding layer provided between the die pad and the semiconductor chip; and a plurality of leads disposed around the die pad, wherein the die pad and the plurality of leads make up a lead frame in cooperation with each other, a cavity is fabricated on the surface of the plurality of leads, and a projecting portion is fabricated next to the cavity.