Abstract: A method for producing a semiconductor device, including the steps of: forming a recess on a first side of a metal substrate; forming a film, made of a metal that is not dissolved by an etchant solution which dissolves the metal substrate, on an inner surface of the recess; punch-pressing a region of the metal substrate that corresponds to an area of the metal film from a second side of the metal substrate so that the area of the metal film formed on the inner surface of the recess becomes substantially flush with the first side of the metal substrate, thereby forming a bonding pad from an extending portion of the metal film that extends from the inner surface of the recess over the first side of the metal substrate; mounting the semiconductor chip on said first side; wire-bonding electrodes of the semiconductor chip and the bonding pads; sealing the first side of the metal substrate that includes the semiconductor chip, the bonding wire and the metal film with resin; and dissolving and removing the metal sub

Abstract: A lead frame for semiconductor devices comprises a plurality of lead sets, each made of a metal strip of a plurality of leads arranged side by side with a small clearance therebetween and a connecting member for integrally connecting the leads. A plurality of such lead sets are arranged in desired positions with respect to each other to form a lead frame assembly.