Self-Propagating Explosive Reactions in Nanostructured AL/NI Multilayer Films Asalocalized Heat Process Technique Formems

This paper describes a novel local heating technique for MEMS soldering and bonding technologies. Nanostructured aluminum/nickel (Al/Ni) multilayer films show self-propagating exothermic reactions, driven by a reduction in atomic bond energy. In this work, we demonstrate the validity of the Al/Ni reactive films as a heat source in manufacturing MEMS solder packages. Dual-source DC magnetron sputtering was employed to deposit the alternative layers of Al and Ni under controlling their thicknesses. By inducing spark, the Al/Ni multilayer film that generates heat enough to melt Au-Sn solder films is ignited, thereby having succeeded in fabrication of Au-Sn film-bonded MEMS elements. The local heating technique using Al/Ni multilayer film’s exothermic reactions is expected to have the great potential as soldering technologies in MEMS.