Simulation Study and Reduction of Reverse Gate Leakage Current for GaN HEMTs

The two-dimensional effect in the reverse gate leakage current of GaN HEMTs is studied by using the TCAD simulation. At the high voltage region, the extension of the potential from the gate to the drain latterly is important role for the reverse gate leakage current characteristics. On the other hands, the electrons flow vertically from the gate electrode to the GaN channel layer at the low gate voltage. Our model explained excellently the experimental results on wide voltage range from low to 80 V. In addition, we studied the gate annealing process as one of the gate current reduction method.