Patent ID: 7456049

Claim:
A method of fabricating a lead frame for a semiconductor device having a semiconductor chip resin-sealed therein, the lead frame including a lead to be electrically connected to the semiconductor chip within sealing resin and to be sealed into the sealing resin such that at least a part of a mounting surface thereof is exposed from the sealing resin, the method comprising: a lead forming step for forming the lead; a side edge coining step for subjecting a side edge of a sealed surface, which is a surface on an opposite side of the mounting surface, of the lead to coining processing from a side of the sealed surface, to form a slipping preventing portion projecting sideward from the lead and having a slipping preventing surface between the mounting surface and the sealed surface of the lead; a step of electrically connecting the sealed surface of the lead and the semiconductor chip to each other; a step of resin-sealing the lead frame, together with the semiconductor chip, such that at least a part of the mounting surface of the lead is exposed; and a step of cutting away an unnecessary part of the lead frame.