Nano-particle reinforced solders for fine pitch applications

In the present study, the influence of nanopowders such as Ni, Cu and Mo on the phase formation, microstructural characteristics, and mechanical behaviour of conventional solder alloys (63Sn/37Pb and Sn/3.8Ag/0.7Cu) has been investigated. The composite solders were prepared by mechanical mixing of nickel (Ni), copper (Cu), and molybdenum (Mo) nano powders with solder alloys followed by cold compaction and sintering. The sintered composite solder alloys were characterized by using SEM and EDX to identify the phase formation and morphological features. The addition of metallic nanopowders such as Ni, Cu, and Mo are observed to influence the grain size and interfacial reaction kinetics of solder alloys. The mechanical properties of the composite solders were measured to study the effect of nanoparticles on the deformation mechanisms.