Wet and Dry Oxidation of Single Crystal β-SiC: Kinetics and Interface Characteristics

Abstract

ABSTRACTSilicon dioxide layers were grown on single crystal (100) β-SiC between 1000°C and 1200°C, in wet O2, dry O2, and wet Ar. All processes demonstrated a linear-parabolic relationship with time. Both wet processes had a slower rate than dry oxidation at 1050°C and below. The activation energies of the linear and parabolic rate constants were calculated for each process. The activation energy of the parabolic rate constant for wet oxidation was found to be inversely dependent on the amount of oxygen present as a carrier gas.The dry oxides exhibited a very flat surface; in contrast, SEM and XTEM reveal that wet oxidation preferentially oxidizes dislocation bands, causing raised lines on the oxide and corresponding grooves in the SiC. It is proposed that the much higher solubility of H2O in SiO2 as compared with that of O2 (103 at 1000°C), allows wet oxidation to be preferential.