| 摘要 |
PROBLEM TO BE SOLVED: To provide an electronic component lead member which is not corroded and shows excellent solderability even in an inferior environment, particularly, a semiconductor chip mounting Pd-plated lead frame with which soldering after an assembly process can be carried out satisfactorily without solder plating. SOLUTION: A lead member has a conductive substrate, a foundation layer which is formed on the substrate and whose main component is Ni, Co or alloy of them, an intermediate layer which is formed on the foundation layer and whose main component is Au, Ag, Pt, Ru, Rh, In, Sn, Sb, Bi, Pb, Zn, Cd or alloy of them and a surface layer which is formed on the intermediate layer and has a thickness of 0.001-0.5μm and whose main component is Pd or Pd alloy. With this constitution, the lead member is hardly corroded and shows excellent solderability even in an inferior environment. Particularly, if the lead member is a lead frame, soldering after an assembly process can be carried out satisfactorily without solder plating. |
