Depth resolution of sputter profiling investigated by combined Auger-x-ray analysis of thin films

Abstract

Conversion of conventional “Auger sputter profiles” into the “depth profiles” has been accomplished by detecting characteristic X-rays produced simultaneously with Auger electrons. We discuss the sputtering through the interface between GeSi films with respect to the following points: determination of the original interface position on the depth scale; asymmetry of the shape of the Auger profiles, and broadening of the interface region due to atomic mixing for different ion masses and energies (He + to Xe +, 0.5 and 5 keV). We found that the best depth resolution of 2.5 nm is obtained for 0.5 keV Xe + which increases to more than 10 nm for He + at 5 keV.