Patent ID: 8581379

Claim:
A lead frame for a resin-seal type semiconductor device, wherein the semiconductor device includes a semiconductor element having an electrode, a bonding wire connected to the electrode of the semiconductor element, and a sealing resin covering and sealing the semiconductor element and the bonding wire, the lead frame comprising: a substrate frame including a plurality of leads; a four-layer plating applied to a portion of the substrate frame that is to be connected to the bonding wire and sealed by the sealing resin, wherein the four-layer plating includes a first plating layer, which is formed from Ni or an Ni alloy, a second plating layer, which is formed from Pd or a Pd alloy, a third plating layer, which is formed from Ag or an Ag alloy, and a fourth plating layer, which is formed from Au or an Au alloy, sequentially laminated in this order on the portion of the substrate frame; and a three-layer plating applied to an exposed region of the substrate frame that is exposed from the sealing resin, wherein the three-layer plating includes the first plating layer, the second plating layer, and the fourth plating layer sequentially laminated in this order on the exposed region of the substrate frame.