Development of Lead-Free Nanocomposite Solders for Electronic Packaging

Abstract

To synthesize new lead-free nanocomposite solders non-coarsening reinforcements (Cu and SnO2) were successfully incorporated into Sn96.5- Ag 3.5. Characterization results convincingly established that composite technology in electronic solders can lead to simultaneous improvement in thermal performance (in terms of lower coefficient of thermal expansion) and mechanical performance (in terms of better microhardess and tensile properties). A threshold addition of reinforcements was observed to aid in optimizing the properties of the composite solder. Composite solders reinforced with nano-size copper particulates yielded the best overall properties. These advanced interconnect materials have the potential to benefit the microelectronics packaging and assembly industry.