XPS study of early stages of Al/Au interface formation

The interface formation between Au polycrystalline substrate kept at temperature of liquid nitrogen and Al deposit and its evolution during sample thermal treatments have been investigated by means of XPS. The intermixing of the Al and Au atoms at the interface occurred readily already at temperature of liquid nitrogen and resulted in the appearance of well‐resolved components on the high‐binding‐energy side of the Au(4f) spectra assignable to AlAu intermetallic phase. The sample annealing resulted in the growth of the amount of intermetallic compound formed at liquid nitrogen temperature. The formation of the initial AlAu phase at the Al/Au interface in our experimental conditions can be explained on the basis of its thermodynamic stability. Copyright © 2009 John Wiley & Sons, Ltd.