Electroless Ni/Pd/Au Plating for Cu Wire Bonding

Abstract

We investigated the Cu and Au wire bonding reliability in electroless Ni/Au plating, electroless Ni/Pd/Au plating and electrolytic Ni/Au plating on the semiconductor package substrate. We found that the minimum Au thickness of electroless Ni/Au and electrolytic Ni/Au for the good wire bonding reliability is 0.3 micrometer. In the case of electroless Ni/Pd/Au, the minimum Au thickness is 0.1 micrometer. These results indicate that electroless Ni/Pd/Au has an advantage on Au thickness as compared with electroless Ni/Au and electrolytic Ni/Au for Cu wire bonding.