Characterization of traps in SiC/SiO2interfaces close to the conduction band by deep-level transient spectroscopy

The effects of the oxidation atmosphere and crystal faces on the traps in SiC/SiO 2 interfaces close to the conduction band were investigated by deep-level transient spectroscopy. It was found that a high density of traps was observed around the energy of 0.16 eV from the edge of the conduction band in interfaces oxidized in a N 2 O atmosphere on the Si-face ( O 1 traps) and C-face ( C 1 traps). From the comparison of their energies, it was concluded that the O 1 traps and C 1 traps had the same origin. We also found that C 1 traps were eliminated only on the C-face by wet oxidation. The simulation using the obtained energy and density of C 1 traps in the interface oxidized in a N 2 O atmosphere on the C-face showed that the trapping of electrons in C 1 was predominant just after the onset of the formation of an inversion layer, where the total electron density generated by the gate voltage was less than 7 × 10 11 cm −2 .