In this study, Ni(P) bond pads joined with Sn solder bumps were stressed with a high current density of 10(4) A/cm(2). Serious electromigration-induced Ni(P) consumption and unusual EM-enhanced diffusion of the interfacial Ni(3)Sn(4) compound layer are observed. However the observed EM-induced Ni(P) consumption and EM-enhanced diffusion of the interfacial Ni(3)Sn(4) compound layer can be effectively retarded by introducing an additional electroless Pd layer on the Ni(P) layer. The improvement in EM resistance due to the Pd layer can be attributed to PdSn(4) formation and Pd solutes in the interfacial Ni(3)Sn(4) layer. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3449119]
