Effect of Passivation on Increasing of AlGaN/GaN HEMT Gate Reverse Leakage

AlGaN/GaN HEMT gate leakage increasing induced by passivation was investigated by employing double gate surface leakage test structure, circle and rectangular Schottky contact structure and metal float gate structure. It was demonstrated that surface leakage is not a major contributor to increasing of gate leakage. Increase of gate leakage depends on augmenting of Schottky contact edge effect and inhibiting "visual gate" between gate and drain