Demonstration of submicron depletion-mode GaAs MOSFET's with negligible drain current drift and hysteresis

We successfully fabricated submicron depletion-mode GaAs MOSFET's with negligible hysteresis and drift in drain current using Ga2O3(Gd2O3) as the gate oxide. The 0.8-mu m gate-length device shows a maximum drain current density of 450 mA/mm and a peak extrinsic transconductance of 130 mS/mm. A short-circuit current gain cutoff frequency (f(T)) of 17 GHz and a maximum oscillation frequency (f(max)) of 60 GHz were obtained from the 0.8 mu m x 60 mu m device. The absence of drain current drift and hysteresis along with excellent characteristics in the submicron devices is a significant advance toward the manufacture of commercially useful GaAs MOSFET's.