Patent ID: 8003444
Filing Date: 2011-08-23
Classification: H01L

Abstract:
1. A method of manufacturing a semiconductor device, comprising: a first step of forming a plating mask having a noble metal plating layer as an uppermost layer, formed by performing noble metal plating on an undercoat, on internal connection terminal portions which are electrically connected to electrode pad portions of a semiconductor element mounted on an obverse surface side of a leadframe material and on external connection terminal portions formed on a reverse surface side of the leadframe material in correspondence with the internal connection terminal portions; a second step of performing etching treatment of a predetermined depth on the leadframe material from the obverse surface side by using the plating mask as a resist mask formed on the obverse surface side after the formation of an etching resist film on the reverse surface side of the leadframe material, so as to cause the internal connection terminal portions to project; a third step of electrically connecting the electrode pad portions of the semiconductor element and the internal connection terminal portions respectively corresponding thereto by a bonding wire after the semiconductor element is mounted on the leadframe material; a fourth step of encapsulating the obverse surface side of the leadframe material including the semiconductor element and the internal connection terminal portions; and a fifth step of performing etching treatment on the reverse surface side of the leadframe material with the etching resist film removed by using the formed plating mask as a resist mask, so as to cause the external connection terminal portions to project and to separate and make independent conductor terminals having the external connection terminal portions and the internal connection terminal portions, wherein there is performed a step of removing plating burrs generated around a periphery of the noble metal plating layer with a shape of a foil of the noble metal plating by eroding the undercoat in the etching treatment.