Effect of a thick buffer in the OFF state simulation of AlGaN/GaN HEMT

Study of the buffer thickness dependence of the OFF state characteristics of AlGaN/GaN HEMTs has beenattempted. The buffer conduction in OFF state has been studiedtaking into account the effect of buffer traps and the response ofthose traps under varying Source-Drain voltage in both the pre-breakdown and near breakdown regions. The temperaturedependence of the current-voltage characteristics have beenaddressed and related to the trap occupancy as a function ofvoltage and temperature. A quantitative measure of the trapconcentration has been estimated to observe the expected device characteristics without any artifacts introduced by the buffer.