A GaAs MOSFET with a liquid phase oxidized gate

Low leakage current density (as low as 10/sup -8/ A/cm/sup 2/ at an applied voltage of 5 V) and high breakdown electrical field (larger than 4.5 MV/cm) of the liquid phase chemical-enhanced oxidized GaAs insulating layer enable application to the GaAs MOSFET. The oxide layer is found to be a composite of Ga/sub 2/O/sub 3/, As, and As/sub 2/O/sub 3/. The n-channel depletion mode GaAs MOSFET's are demonstrated and the I-V curves with complete pinch-off and saturation characteristics can be seen. A transconductance larger than 30 mS/mm can be achieved which is even better than that of MESFET's fabricated on the same wafer structure.