In this paper, we report a new alternative to the conventionalsolder. It is based on In-Sn multilayer composite design. This is afluxless, oxidation-free, and most important of all, a non-eutecticsoldering technique that can achieve a remelting temperaturesignificantly higher than the bonding temperature. The In-Snnon-eutectic multilayer alloy so designed has the composition of 13.9atomic% In and 86.1 atomic% Sn. The SEM and EDX analyses performed onthe joint cross section clearly indicate a uniform joint thickness of 9μm, while the joint microstructure is clearly visible and nearlyvoid-free. The EDX results obtained also successfully demonstrate thatthe entire joint is heavily Sn-rich, as anticipated. The remeltingtemperature of several joints was analysed. It ranges from 175 to190° C, The results clearly show that the joint composition isheavily Sn-rich, a very significant advantage from which it maximizesthe temperature tolerance the device package can possibly handle
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