Mechanism of power density degradation due to trapping effects in AlGaN/GaN HEMTs

AlGaN/GaN HEMTs are promising devices for very high power applications. These transistors present high breakdown voltages and have already shown their ability to operate at high temperature. But their power performances are limited because of the presence of traps within the material, decreasing the drain current density. In order to predict the loss of power density and quantify trapping effects, simulations need to be performed with a suitable model, which accounts for these parasitic trapping effects. This paper deals with the characterization, modeling and simulation of trapping effects and power behavior of a 1 mm GaN device on a SiC substrate. Experimental results are compared to the simulations.