High breakdown field multi-kV UWBG AlGaN transistors

We demonstrate high-performance UWBG AlGaN PolFETs exhibiting a state-of-the-art combination of nearly 1 A/mm on-state current (∼960 mA/mm) and a large breakdown field (>4.8 MV/cm) in high carrier density (1.15 × 1013 cm−2). Multi-kV robustness is successfully demonstrated, exhibiting 1.28 and 2.17 kV by utilizing a gate-connected field plate structure in 3.9 and 6.8 μm LGD, corresponding to the extremely low specific on-resistance of 1.25 and 2.86 mΩ cm2, respectively. High RF performance is also achieved, providing fT and fMAX of 8.5 and 15 GHz, respectively, for 3.9 μm LGD. These results highlight UWBG AlGaN as a platform for both high-voltage RF and power applications.