Title :
MOSFETs Made From GaN Nanowires With Fully Conformal Cylindrical Gates
Author :
Blanchard, Paul T. ; Bertness, Kris A. ; Harvey, Todd E. ; Sanders, Aric W. ; Sanford, Norman A. ; George, Steven M. ; Seghete, Dragos
Author_Institution :
Nat. Inst. of Stand. & Technol., Boulder, CO, USA
fDate :
5/1/2012 12:00:00 AM
Abstract :
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. Reverse-bias breakdown voltages exceeded the largest gate voltage tested (-35 V). The nanowire MOSFETs showed complete pinchoff, with threshold voltages between -4 and -12 V. Maximum transconductances exceeded 10 μS, 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.
Keywords :
III-V semiconductors; MOSFET; alumina; atomic layer deposition; electric breakdown; electrical conductivity; gallium compounds; nanowires; optimisation; tungsten; wide band gap semiconductors; GaN; ON-OFF current ratio; W-Al2O3; atomic layer deposition; charge traps; fully conformal cylindrical gates; gate voltage; gating hysteresis; memory effects; metal-oxide-semiconductor field effect transistors; nanowire MOSFET; reverse-bias breakdown voltages; threshold voltages; transconductances; voltage -4 V to -12 V; Gallium nitride; Logic gates; MOSFETs; NIST; Nanowires; Physics; Atomic layer deposition (ALD); MOSFETs; conformal gate; gallium nitride; nanowires;
Journal_Title :
Nanotechnology, IEEE Transactions on
DOI :
10.1109/TNANO.2011.2177993
