In order to study the electronic structures of the SiC/SiO2 interface, which was made by the oxidation of SiC, structural models were constructed for the dangling-bond free interfaces of 4H-SiC/SiO2 with the substrate orientations of (00•1) and (11•0). Ab initio calculations were carried out and it was found that a stretched oxygen atom appeared in the near-interface region of the SiO2 insulator for the 4H-SiC(00•1)/SiO2 interface but not for the 4H-SiC(11•0)/SiO2 interface. The origin of the experimentally found oxygen vacancy defect near to the SiC(00•1)/SiO2 interface was considered.

Ab initio Theoretical Study of an Oxygen Vacancy Defect at the 4H-SiC(0001)/SiO2 Interface. E.Okuno, T.Sakakibara, S.Onda, M.Itoh, T.Uda: Physical Review B, 2009, 79[11], 113302