Electrical Properties of Thermal Oxide on 3C-SiC Layers Grown on Silicon

In this paper, the electrical properties of a thermal oxide (SiO2) grown onto 3C-SiC layers on silicon were investigated, by monitoring the behavior of MOS capacitors. In particular, the growth rate of thermal SiO2 was dependent on the different surface roughness condition. However, independent of the roughness a high density of positive charge was detected. The sample having the smooth surface (subjected to CMP) showed a notably improved dielectric breakdown (BD) field. However, the best BD on macroscopic MOS capacitors was still far from the ideal behavior. Additional insights could be gained employing a nanoscale characterization that revealed the detrimental role of persisting extended defects in the semiconductor. In the semiconductor region far from extended defects the nanoscale BD kinetics was nearly ideal.