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.