High-power and high-efficiency AlGaN/GaN HEMT operated at 50 V drain bias voltage

We describe high power 70 W CW operation at 52 V drain bias voltage (Vds) using 24-mm gate-periphery AlGaN/GaN HEMTs on SiC substrate. A 48 W output power with the drain efficiency of 60% was also obtained at Vds of 50 V under the efficiency-matched condition near class-B. At 40 V, the drain efficiency reached 68%. Vds dependence of third order-intermodulation (IM3) was also characterized at Vds up to 50 V. This is the first report about IM3 profile characterization for a large gate-periphery device at Vds of 50 V. We also investigated RF-stress life test at Vds up to 40 V. The AlGaN/GaN HEMT in this study exhibited good reliability over 100 h.