Rapid Oxidation of SiC Using Microwave-Discharged O2 Plasma at Low Temperatures (< 300°C)

The rapid oxidation of 6H–SiC has been achieved using O2 plasma, which is discharged by a microwave of 2.45 GHz at low temperatures below 300°C. X-ray photoelectron spectrometry (XPS) measurements reveal that O2 plasma processing oxidizes SiC into the stoichiometric SiO2 layer. The SiO2 layer with a thickness of 22 nm is obtained after O2 plasma processing for 10 min at a sample temperature of 200°C, which is 15 times faster than thermal oxidation in dry O2 gas at 1150°C. There is a large amount of interface state at the SiO2/SiC interface in an as-oxidized sample as well as in the case of the thermal oxidation. The formed SiO2 layer shows a break down field strength of about 9.5 MV/cm, which is comparable to that of the thermal oxide layer.