Evolution of Mound Morphology in Reversible Homoepitaxy on Cu(100)

Abstract

Evolution of mound morphology in reversible homoepitaxy on Cu(100) was studied via spot-profile-analysis (SPA) LEED and scanning tunneling microscopy. The mound separation shows coarsening vs growth time with $L(t)\ensuremath{\sim}{t}^{1/4}$, in support of theory based on capillarity between mounds. The growth ultimately reaches a steady state characterized by a selected mound angle of $\ensuremath{\sim}5.6\ifmmode^\circ\else\textdegree\fi{}$. We suggest that this results from a downhill current driven by step edge line tension in balance with an uphill current due to the Schwoebel barrier effect. Also, we have clarified the interpretation for the evolution of the SPA-LEED profile from a ring structure to a single time-invariant peak.