Step Structures and Adatom Diffusion on SiC Surfaces

Abstract

Recent first-principles studies on step structures and adatom diffusion on SiC(0001) surfaces are reviewed. SiC is a promising material for next-generation power electronics, and SiC power devices are already on the market. The obtained formation energies of all the possible atomic steps provide a definite identification of the most relevant atomic step for two vicinal directions inclined toward either <1100> or <1120> direction on SiC(0001) surfaces. Relations between the energetics of surface steps and macroscopic step morphology are discussed. Diffusion mechanism for Si, C, and H adatoms which are three important chemical elements of gas sources of chemical vapor deposition (CVD) for SiC is revealed both on the surface terraces and near the surface steps.