stitch bonding of palladium coated copper wires

Palladium coated copper (PCC) wire bonding on roughen preplated leadframe is a preferred electrical interconnect in the semiconductor package due to its robustness package performances. PCC wire is replacing bare copper wires to eliminate the copper oxidation problem. Whereas, roughen treated preplated leadframe is used to eliminate post-plating of leadframe as well as to enhance the adhesion of leadframe to the epoxy mold compounds. However, role of the plating thickness of roughen preplated leadframe on the PCC wire has not yet been fully understood. Thus, this paper investigates stitch bonding strength of PCC wire on the AuAg/Pd/Ni/Cu preplated leadframe