The research objective of this grant is to determine the synthesis-structure-property relationships in nanoscale lead-free solders (nanosolders) for joining/bonding applications. Although nanotechnology has experienced dramatic development in the area of electronics and devices, some key challenges have to be overcome in order to reach the stage of nanoelectronics manufacturing and commercialization. To date, one major challenge in nanoelectronics and device research is the effective joining of nanoelements (such as nanowires or carbon nanotubes) with low contact resistance to obtain reliable electrical and thermal interconnection. In this project, the PIs will synthesize several promising lead-free nanosolders, in the form of isotropic and anisotropic nanostructures (nanospheres, nanorods, nanowires, etc), and determine the fundamental properties underlying their potential applications in nanoscale assembly and nano-joining. Melting points of nanosolders, nanoscale wetting, inter-metallic formation, and phase transformation will be studied. The potential issues of nanosolders, including surface oxidation, will be probed and addressed through collaboration with local electronics companies in the New England and US Northeast Region.
If successful, this interdisciplinary collaborative effort will provide a pathway into further miniaturization of nanoelectronic devices with high quality and reliability. Lead-free nanosolder materials and nano-soldering techniques are expected to play a key role in the electronics industry, as well as in various areas of advanced materials joining, including medical devices, nanoelectromechanical systems (NEMS), sensors, aerospace and defense industries. The results from this project will be disseminated through the NSF NSEC Center for High-rate Nanomanufacturing (CHN), the New England Lead-free Electronics Consortium (over 30 local and national companies), the Integrated Electronics Engineering Center (IEEC) in New York, and professional conferences. Technical seminars, joint workshops, and conferences on nanosolders and nanoelectronics assembly will be organized by the PIs at the two institutions in Massachusetts and New York. The new findings will also be integrated into undergraduate and graduate courses, including the development of new nano-joining lab modules, and in K-12 outreach with the Museum of Science (MoS) in Boston.