Mound shape instability in multilayer Ag(001) homoepitaxy: The role of corner-crossing

摘要

We have investigated the growth of Ag(001) in the multilayer regime by high-resolution electron diffraction (SPA-LEED). Ag deposition at temperatures above 180 K results in the growth of approximately square mounds with a predominant <1 (1) over bar0> step termination which is thermodynamically favored. Surprisingly, when the deposition temperature is reduced below 130 K, instead of observing a random roughening of the step pro le, as expected in a self-affine growth regime, the proliferation of <001> oriented facets is observed. We attribute our observation to the de-activation of corner crossing, as well as to the presence of easy pathways for interlayer diffusion down the {111} facets which are formed at <1 (1) over bar0> steps. [References: 23]