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Updated: Apr 28, 2026

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Tuning from thermionic emission to ohmic tunnel contacts via doping in Schottky-barrier nanotube transistors
Yung-Fu Chen1, Michael S Fuhrer
1Department of Physics and Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742-4111, USA.
Abstract:
Electrical power >1 mW is dissipated in semiconducting single-walled carbon nanotube devices in a vacuum. After high-power treatment, devices exhibit lower on currents and intrinsic, ambipolar behavior with near-ideal thermionic emission from Schottky barriers of height one-half the band gap. Upon exposure to air, devices recover p-type behavior, with positive threshold and ohmic contacts. The air-exposed state cannot be explained by a change in contact work function but instead is due to doping of the nanotube.
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