Low-Noise Microwave Performance of 0.1 μ m Gate AlInN/GaN HEMTs on SiC

We report the first microwave noise characterization of AlInN/GaN HEMTs. Transistors with a 0.1 μ m gate implemented on a semi-insulating SiC substrate achieve a maximum current density of 1.92 A/mm atVGS= 0 V, a measured transconductancegM= 480 mS/mm, and a peak current gain cutoff frequencyfT= 121 GHz with a simultaneous maximum oscillation frequencyfMAX= 142 GHz. At 10 (20) GHz, our HEMTs exhibit a minimum noise figureFminof 0.62 (1.5) dB together with a high associated gainGAof 15.4 (13.3) dB. TheFminvalues are among the lowest reported in nitride HEMTs, and theGAvalues are the best so far found in the literature, demonstrating the excellent potential of AlInN/GaN HEMTs for low-noise microwave applications.