Effect of transition metals on the interfacial reactions in electroless Ni(P)-solder interconnections

Abstract

The Ni-Sn-P, which was regarded to be mechanically weak and susceptible to brittle fracture. The IMC spalling at SAC/Ni-P interfaces may occur during reflow and the degree of spalling increases with the P content of Ni-P. This phenomenon is closely related to the formation of Ni-Sn-P.There is very limited study on interfacial interactions between TM added SAC solders and electroless Ni-P substrate.To understand the effect of TM additions and get an in-depth insight into this alloy system, this study prepared near eutectic Sn-Ag-Cu-TM (TM=Ni, Co and Zn) for investigation. In addition, nanoindentation test was performed to evaluate the mechanical characterization of the interfacial reaction products.