Study of nickel silicide contact on Si/Si1-xGex

Abstract

The properties of nickel silicide formed by depositing nickel on Si/P+ - Si1-xGex layer are compared with that of nickel germanosilicide on P+ - Si1-xGex layer formed by depositing Ni directly on P+ - Si1-xGex layer without silicon consuming layer. After thermal annealing, nickel silicide on Si/P+ S Si1-xGex layer shows lower sheet resistance and specific contact resistivity than that of nickel germanosilicide on P+ - Si1-xGex layer. In addition, small junction leakage current is also observed for nickel silicide on Si/P+ - Si1-xGex/N - Si diode. In summary, witha Si consuming layer on top of the Si1-xGex, the nickel silicide contact formed demonstrated improved electrical and materials characteristics as compared with the nickel germanosilicide contact which was formed directly on Si1-xGex layer.