GaN double heterojunction field effect transistor for microwave and millimeterwave power applications

摘要

We report development of a novel AlGaN/GaN/AlGaN double heterojunction field effect tansistor (DHFET) with improved device performance over the conventional single heterojunction GaN FET (SHFET). The GaN DHFETs with low Al content Al_0.04Ga_0.96N buffer layer exhibit three orders of magnitude lower subthreshold drain leakage current and almost three orders of magnitude higher buffer isolation than corresponding SHFET devices (600 MΩ/sq. vs. 1 MΩ/sq.). In GaN DHFET's with 0.15 μm conventional T-gates we observed 30% improvement in saturated power density and 10% improvement in PAE at 10 GHz over a corresponding SHFET device.