Some Experimental Facts About Temperature-Induced Surface Diffusion of Silver During Auger Sputter Depth Profiling of Multilayered Ni/Ag Thin Films

Thermally-induced surface diffusion studies were carried out on the two outer nickel layers of a Ni/Ag/Ni/Ag/... multilayered thin-film structure. The thickness of the Ni layers was 50 nm and the silver film was approx 4 nm thick. The 4 keV argon ions were used for sputter profiling and two 5 keV electron bemas (80 nA) were used to excite the Auger emission. Measurements were made of the surface diffusion kinetics by monitoring the time dependence of the total Ag Auger intensity at approximately the middle of the first and the second outer Ni layers. One possible mechanism responsible for such pronounced Ag enhancement at elevated temperatures at the Ni layers is the thermally activated process of Ag surface diffusion.