Microwave performance of GaAs MOSFET with wet thermally oxidized InAlP gate dielectric

This paper reports the first demonstration of a microwave-frequency operation of a GaAs MOSFET fabricated using a wet thermal oxidization of InAlP lattice-matched to GaAs to form a native-oxide gate insulator. Devices with 1-μm gate lengths exhibit a cutoff frequency (f_T) of 13.7 GHz and a maximum frequency of oscillation (f_max) of 37.6 GHz, as well as a peak extrinsic transconductance of 73.6 mS/mm. A low-leakage current density of 3.8×10/sup -3/ A/cm² at 1-V bias for an MOS capacitor demonstrates the good insulating properties of the /spl sim/ 11-nm thick native gate oxide.