SURFACE TREATMENT FOR LEAD FRAME FOR SEMICONDUCTOR

摘要

PURPOSE:To form an inexpensive lead frame having high reliability by a method wherein a brazing material functioning at the time of thermally pressing a semiconductor element is previously provided as a solder plating layer on a lead frame for semiconductor and tin is deposited to the surface of the plating layer only by a displacement method. CONSTITUTION:An Ni plating layer 2 is formed on a lead frame substrate 1 and a P-Ni alloy plating layer 3 is formed on the layer 2. Furthermore, a solder plating layer 5 is formed on the semiconductor element section 4 of the lead frame and a tin displacement film 6 is formed on the layer 5. This improves the discoloration resistance of solder and stabilizes wettability.