Analysis of the electron traps at the 4H-SiC/SiO_2 interface using combined CV/thermally stimulated current measurements

摘要

The interface traps at the 4H-SiC/SiO_2 interface are studied using thermally stimulated current (TSC) and CV-techniques. We demonstrate that the electron traps near the 4H-SiC conduction band edge at the 4H-SiC/SiO_2 interface are composed of two groups of trapping levels differing by their mechanisms of the electron exchange with the semiconductor. These two groups of traps are found for a variety of differently prepared thermal oxides. It is assumed that both groups of traps are caused by the same interfacial defect distributed from interface into the oxycarbide transition region.