| 摘要 |
PROBLEM TO BE SOLVED: To provide a lead frame having excellent bondability even when a thick Cu plating layer is formed. SOLUTION: The lead frame includes a cold rolled stainless steel strip containing C of 0.03 mass% or less and Cr of 11.5-13.5 mass% and having a hardness of HV 200 or more used as a base material, and the Cu plating layer which has a thickness of 5-30μm and which is formed on the surface of the base material. The Cu plating layer 1 is preferably a matt electric Cu plating layer which does not contain a brightener so as to obtain high electric conductivity and heat conductivity. When the plating layer having the HV 100 or more is cured, the bondability is further improved. Even in the lead frame in which the plating layer having a relatively thick film is formed, the bondability at a high speed bonding time is stabilized, and an Au wire 2 is connected with a high connecting strength. COPYRIGHT: (C)2004,JPO |
