Patent ID: 6518508
Filing Date: 2003-02-11
Classification: H01L,Y10T

Abstract:
A lead frame for a semiconductor package consisting of:a base metal layer made of copper (Cu), Cu alloy or iron-nickel (Feâ€”Ni) alloy; an underlying plating layer formed on at least one surface of the base metal layer and made of Ni or Ni alloy; an intermediate plating layer formed on the underlying plating layer to a thickness of about 0.00025 to about 0.1 &mgr;m (about 0.1 to about 4 microinches) and made of palladium (Pd) or Pd alloy; and an outer plating layer formed on the intermediate plating layer to a thickness of about 0.05 to about 0.75 &mgr;m (about 2 to about 30 microinches) and made of silver (Ag) or Ag alloy.