High-temperature power performance of X-band recessed-gate AlGaN/GaN HEMTs

Record power densities have been demonstrated with AlGaN/GaN HEMTs using the field-modulating plate gate structure. This approach creates a trade-off between breakdown voltage and gain, which can be improved by performing gate recessing. In this work, 0.25-μm recessed-gate AlGaN/GaN devices were fabricated on SiC. At 10 GHz, saturated power density of 6.35 W/mm with peak PAE of 50.2% with assoc. gain of 13.2 dB at peak PAE at V_ds = 35 V was achieved. Comparison of DC, small-signal, RF power, and high-temperature performance between recessed and non-recessed will be discussed.