100GHz depletion-mode Ga2O3/GaN single nanowire MOSFET by photo-enhanced chemical oxidation method

We reported transport characterization on [112̅0]GaN single nanowire (SNW)-MOSFET laterally- and directionally-grown on (0001) sapphire substrates. The 60nm-dia. Ga₂O₃/GaN SNW-MOSFET of 0.1μm gate length was shown to exhibit a saturation current of 160μA, current on/off ratio of 10⁵, swing of 85mV/dec, transconductance of 85μS, and unity current gain bandwidth f_t at 95GHz. From a 3D diffusion and drift model analysis, it is shown that a polarization induced 2D electron gas (2DEG) density of 7 × 10¹² cm² with mobility of 1000cm²/V-sec confined at the interface of semi-polar {11̅01̅} GaN/Ga₂O₃ was responsible for the high-speed transport characteristics.