Impact of O₂ post oxidation annealing on the reliability of SiC/SiO₂ MOS capacitors*

The effects of dry O2 post oxidation annealing (POA) at different temperatures on SiC/SiO2 stacks are comparatively studied in this paper. The results show interface trap density (D it) of SiC/SiO2 stacks, leakage current density (J g), and time-dependent dielectric breakdown (TDDB) characteristics of the oxide, are affected by POA temperature and are closely correlated. Specifically, D it, J g, and inverse median lifetime of TDDB have the same trend against POA temperature, which is instructive for SiC/SiO2 interface quality improvement. Moreover, area dependence of TDDB characteristics for gate oxide on SiC shows different electrode areas lead to same slope of TDDB Weibull curves.