Enhanced ductility and oxidation resistance of Zn through the addition of minor elements for use in wide-gap semiconductor die-bonding materials

Abstract

Pure Zn is one of the best die-attachment candidates for use in next-generation wide-gap semiconductor power devices operating at temperatures up to 300°C. However, it has certain drawbacks when used at high operating temperatures: poor ductility and limited oxidation resistance. In this study, we investigated the effect of adding minor elements – Ca, Mn, Cr, and Ti – in improving Zn ductility and oxidation resistance. This addition significantly reduced the grain size of the microstructure, thus improving the tensile strength and elongation of pure Zn. In addition, the minor elements addition significantly improved oxidation resistance of pure Zn. Consequently, because of higher ductility and oxidation resistance, the interconnection ability of Zn alloys as die-attachment candidates was significantly enhanced.