Electronic properties of SiO2/SiC interfaces

Oxidation of silicon carbide (SiC) provides a possibility to combine the unique electronic and thermal properties of this semiconductor with the surface passivation attained by the natural insulating oxide SiO 2 , in a similar way as it is done for silicon. However, the electron transport at the oxidized SiC surfaces is deteriorated by the SiC/oxide interface imperfections much more strongly than in the Si/SiO 2 structures. Two main contributions to the enhanced SiC/SiO 2 defect densities are revealed, including the carbon-related states and the near-interfacial oxide defects with energy levels in the SiC bandgap. These defects can be formed not only during the oxide formation or annealing, but, also, as a result of charge injection at the SiC/oxide interface which stresses the importance of the degradation effects in the SiC electronic devices.