Novel lead-free Sn-Cu-xBi nanosolders by chemical reduction method.

: With environmental concerns on the toxicity of lead, investigations on lead-free solders become crucial. Studies on lowering process temperature of lead-free solders are required, because the melting points of lead-free solders are higher than original SnPb solders. Melting points of binary solders could be decreased by addition another materials. In this study, Sn-Cu-xBi lead-free nanoparticles were synthesized with precisely controlled size and composition by chemical precipitation method. Effects of different precursor concentration and surfactant addition were discussed. The influence of different amounts of Bi in the SnCu-based nano-particles was also probed.