On the impact of carbon-doping on the dynamic Ron and off-state leakage current of 650V GaN power devices

A strong positive correlation between dynamic Ron and the ionization of buffer traps by injection of electrons from the Si substrate is presented. By exploring different Carbon doping profiles in the epi layers, the substrate buffer leakage is substantially reduced, which in turns results in lower dynamic Ron. The traps in the epi structure are characterized by different electrical techniques such as drain current transient, on-the-fly trapping and ramped back-gating experiments.