Self-ordering of nanofacets on vicinal sic surfaces

Abstract

Vicinal [Formula presented] and [Formula presented] surfaces have been investigated using atomic force microscopy and cross-sectional high-resolution transmission electron microscopy. We observed the characteristic self-ordering of nanofacets on any surface, regardless of polytypes and vicinal angles, after gas etching at high temperature. Two facet planes are typically revealed: (0001) and high index [Formula presented] that are induced by equilibrium surface phase separation. A [Formula presented] plane may have a free energy minimum due to attractive step-step interactions. The differing ordering distances in [Formula presented] and [Formula presented] polytypes imply the existence of SiC polytypic dependence on nanofaceting. Thus, it should be possible to control SiC surface nanostructures by selecting a polytype, a vicinal angle, and an etching temperature. © 2003 The American Physical Society.