Auger in-depth profiling of Ag layer epitaxially grown on Pb (111) surface: A direct evidence of substrate diffusion.

During the epitaxial growth of Ag on Pb(111) surface, constant diffusion of Pb through the Ag layer occurs and forms a saturated ordered monolayer of Pb on the Ag surface. Auger in-depth profiling of this system shows that the time-dependent diffusion of Pb follows an exponential function. The diffusion time constant tau is found to be ~1-2 minutes in this study.