Effects of oxidation conditions on electrical properties of SiC-SiO2 interfaces

Electrical properties of metal-oxide-semiconductor (MOS) devices fabricated on 3C-SiC single crystalline films on (100)Si substrates have been examined by capacitance-voltage method and deep level transient spectroscopy. The electrical properties such as carrier concentration, interface states, fixed oxide charge and deep traps are strongly related to the oxidation ambient and temperature. It has been found that the interface state density of the order of 1010 cm−2 eV−1 can be achieved by wet oxidation at 1000 °C. The influence of preferential oxidation of antiphase grain boundaries is considerable on the carrier concentration and the interface state density in the case of wet oxidation. From a practical point of view, the wet oxidation is concluded to be superior to the dry oxidation because of the lower densities of fixed oxide charge, interface states, and deep traps.