Atomic Structure of Hexagonal 6H– and 3C–SiC Surfaces

Abstract

The crystallography of hexagonal SiC surfaces prepared ex situ by chemical methods was investigated by low energy electron diffraction (LEED) structure analysis. The surface morphology was analyzed by considering mixtures of domains with different surface layer stacking geometries. On the 6H–SiC(0001) surface ABCACB stacking is the dominating termination, covering about 80% of the surface. On [Formula: see text] all three possible surface stacking sequences are present. The (111) surface of a 3C–SiC film sample shows linear stacking of layers with only one domain orientation present. In contrast to the carbon-terminated 6H sample, the silicon-terminated surfaces are covered by an oxygen layer with the adatoms bound on top of silicon.