High pressure oxidation of 4H-SiC in nitric acid vapor

High pressure chemical vapor oxidation of SiC in nitric acid vapor is reported. Higher growth rate at temperatures as low as 400 to 500°C has been achieved. The oxidation kinetics has been studied. It has been observed that the growth rate is strongly dependent on temperature, and the thickness of the oxide increases almost linearly with time within the error limits. X-ray photoelectron spectroscopy (XPS) measurement has been carried out to study the composition of the oxide. Room temperature electrical characterization (current-voltage and capacitance-voltage) has been carried out to estimate the oxide breakdown field strength, oxide charges, and interface state density. It is observed that prolonged oxidation or oxidation at higher temperature in acid ambient deteriorates the quality of oxide.