| 摘要 |
<p>PURPOSE:To hold down the diffusion rate of Sn so as to prevent an Sn or a solder plating layer from deteriorating in adhesion or separating by a method wherein a part of a first-surface treated layer and all the third surface-treated layer are coated with resin, and the first-surface treated layer is interposed between a second surface-treated layer and a resin sealed region. CONSTITUTION:All outer lead 4 and a part of an inner lead 3 located inside a dam bar 5 are subjected to an Ni-plating treatment to form a first surface- treated layer 7. In succession, the surface of a region which is located outside of a resin sealed region and does not include the outer lead 4 is coated with a tin or a solder plating film to form a second surface-treated layer 8. Furthermore, a device mounting pad 2 and a wire bonding area 10 located at the tip of the inner lead 3 are subjected to a base partial plating treatment, which is coated with a gold or a tin plating layer to form a third surface-treated layer 9. In the lead frame 1 provided with the first third treated layer, 7-9, a semiconductor device 13 is fixed onto the device mounting pad 2, the bonding pad of the semiconductor device 13 is connected to the third surface-treated layer 9 located at the tip of the inner lead 3 with a wire 14 to constitute an electrically conductive circuit.</p> |
