2DEG-Concentration-Modulated High-Power-Density AlGaN/GaN RF HEMTs

Herein, by modulating 2DEG concentration ( n s ), a superior GaN RF HEMT with a high-Al-content AlGaN barrier is reported for high power-density ( P out ) X-band applications. Thanks to a high n s of 1.3×10 13 cm -2 enabled by the Al 0.32 Ga 0.68 N barrier, as well as the regrown n + -GaN ohmic contacts, the device exhibits an output drain current ( I D ) of 1.6 A/mm, an on-resistance ( R ON ) of 1.10 Ω·mm, and maintain a breakdown electric field ( E BC ) of ~0.8 MV/cm. As a result, at 10 GHz, P out of 10.4 W/mm and power-added efficiency (PAE) of 63.2% are obtained at a moderate drain bias ( V D ) of 28 V. Notably, the results of I D – E BC , P out – V D , and the figure-of-merit P out / V D of our device marks one of the best records among X-band GaN HEMTs, showing strong competitiveness of high-Al-content AlGaN/GaN HEMTs for high- P out RF applications.