Advances of micro/nano particle-enhanced Sn-based composite solder

Sn-based solder is a widely used interconnection material in the field of electronic packaging, but due to the rapid development in this area, the performance requirements for Sn-based solder are also becoming increasingly demanding. In recent years, adding micro/nano reinforcement phases to Sn-based solder has provided a solution for improving the intrinsic properties of the solder. This paper reviews the progress of Sn-based micro/nano reinforced composite solders over the past decade. The types of reinforcement particles, preparation methods of composite solders, and the strengthening effects on microstructure, wettability, melting point, mechanical properties, and corrosion resistance under different particle addition levels are discussed and summarized. The mechanisms of performance enhancement are summarized based on material strengthening effects such as grain refinement and second-phase dispersion strengthening. In addition, we discuss the current shortcomings of such composite solders and possible future improvements, establishing a theoretical foundation for the future development of Sn-based solders.