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

摘要

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 (SiO_2) capped p-type silicon substrate. The GaN nanowires were characterized with a length of 20μm 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 SiO_2 passivated GaN single nanowire FETs compared the ones without SiO_2 layer. We ascribed this observation to the suppression of the surface states density of GaN nanowires by the oxide layer.