Enhanced Carrier Transportation on Passivated Gallium Nitride Single Nanowire Field-Effect Transistor

We reported on the enhanced carrier transportation in gallium nitride (GaN) single nanowire field-effect transistor (FET) with top gate structure. The GaN nanowires were synthesized by a selective-site growth mechanism using vapor-liquid-solid (VLS) method on a silicon-dioxide (SiO2) capped p-type silicon substrate. The GaN nanowires were characterized with a length of 20000nm and ~80nm diameter as observed by scanning electron microscope. Data from the electrical characterization revealed a twenty-fold increase of the saturation current on the SiO2 passivated GaN single nanowire FETs compared the ones without SiO2 layer. We ascribed this observation to the suppression of the surface states density of GaN nanowires by the oxide layer.