Performance optimization of lateral AlGaN/GaN HEMTs with cap gate on 150-mm silicon substrate

Abstract

A further leakage reduction of AlGaN/GaN HEMTs with cap gate (CG-HEMTs) has been achieved by optimizing the gate structure and the gate etching process. The optimized CG-HEMTs single finger power HEMTs deliver IDSmax=533mA/mm at least with gate length of 0.5um and show a median gate leakage current of 20nA/mm 25°C measured at a drain voltage of 200V. The breakdown voltage (BV) of CG-HEMTs was evaluated by the variation of drain-to-gate spacing (LDG) larger than 8μm. Furthermore, we show that the forward voltage of CG-HEMTs can be improved by shrinking the lateral dimension of the edge termination due to reduced series resistance.