GaN Metal Oxide Semiconductor Field Effect Transistors

A GaN based depletion mode metal oxide semiconductor field effect transistor (MOSFET) was demonstrated using Ga sub 2 O sub 3 (Gd sub 2 O sub e) as the gate dielectric. The MOS gate reverse breakdown voltage was > 35V which was significantly improved from 17V of Pt Schottky gate on the same material. A maximum extrinsic transconductance of 15 mS/mm was obtained at V sub (ds) = 30 V and device performance was limited by the contact resistance. A unity current gain cut-off frequency, f sub (tau), and maximum frequency of oscillation, f sub (max) of 3.1 and 10.3 GHz, respectively, were measured at V sub (ds) = 25 V and V sub (gs) = -20 V.