MOSFETs Made From GaN Nanowires With Fully Conformal Cylindrical Gates

We report novel metal-oxide-semiconductor field effect transistors (MOSFETs) based on individual gallium nitride (GaN) nanowires with fully conformal cylindrical gates. The W/Al2O3 gates were deposited by atomic layer deposition. Reversebias breakdown voltages exceeded the largest gate voltage tested (-35 V). The nanowire MOSFETs showed complete pinchoff, with threshold voltages between -4 and -12V. Maximum transcon-ductances exceeded 10 mu S, and ON/OFF current ratios higher than 10(8) were measured. Significant gating hysteresis and memory effects were also present, indicative of charge traps. Although further optimization is needed, these results represent a promising step forward in the development of efficient GaN nanowire-based FETs.