Development of Novel MEMS Soldering Technique Using Self-Propagating Exothermic Reaction in Al/Ni Multilayer Films
Hiroshi FUJITA, Takahiro NAMAZU and Shozo INOUE
Abstract:This paper describes a novel local heat process technique for MEMS soldering technology. Al/Ni multilayer film deposited by DC magnetron sputtering shows self-propagating exothermic reaction. By applying a spark to the reactive film, the film generates heat enough to melt Au-Sn solder film. The heat of reaction depended on Al/Ni bilayer thickness and the total film thickness. We used the Al/Ni multilayer film as a local heat source in MEMS soldering packages. Au-Sn solder film-bonded silicon elements by the local heating was fabricated without other external heat sources, and the bond strength was characterized. The local heating technique by Al/Ni multilayer film's exothermic reaction would likely have the potential for MEMS soldering technology. Key Words:Al/Ni multilayer film, Self-propagating exothermic reaction, MEMS package, Au-Sn solder film.