First-Principles Calculations of Schottky Barrier Heights of Monolayer Metal/6H-SiC{0001} Interfaces

Abstract

Schottky barrier heights (SBHs) of monolayer metal/6H-SiC{0001} interfaces have been calculated by the first-principles projector augment-wave (PAW) method in order to examine the dependence on metal species as well as surface termination of SiC. Generally, p-type SBHs of the C-terminated (000-1) interfaces are smaller than those of the Si-terminated (0001) interfaces, because of the interface dipoles caused by substantial charge transfer. The SBHs of the Si-terminated interfaces range within a relatively narrow energy region without clear correlation with metal electronegativity, although those of the C-terminated interfaces show rather specific dependence on metal electronegativity except for systems with Fe and Co. The different dependence on the metal species for the Si- and C-terminated interfaces has been analyzed from the interface electronic structure as compared with previous theoretical models and experiments.