Investigation of Additional Elements in Sn-Bi Based Low-Temperature Solder

In order to minimize the energy consumption and thermal warpage during reflow process, low-temperature solder have become a hot research area in recent years. In this study, Sn-Bi system was chosen as the starting point for the study of low-temperature solders. By increasing the proportion of Sn and adding additional elements in Sn-Bi solder, it was expected that the melting point will be lowered and the mechanical properties will be improved at the same time. Then, influence of Sb addition on Sn-Bi solder grain refinement before and after thermal aging was investigated. Finally, several properties of different additional elements, including melting point, interfacial reaction, wettability and microstructure evolution were investigated.