Achieving high-current carbon nanotube emitters.
When a carbon nanotube emitter is operated at high currents (typically above 1 microA per emitter), a small voltage drop ( approximately few volts) along its length or at its contact generates a reverse/canceling electric field that causes a saturation-like deviation from the classical Fowler-Nordheim behavior with respect to the applied electric field. We present a correction to the Fowler-Nordheim equation to account for this effect, which is experimentally verified using field emission and contact electrical measurements on individual carbon nanotube emitters. By using rapid thermal annealing to improve both the crystallinity of the carbon nanotubes and their electrical contact to the substrate, it is possible to reduce this voltage drop, allowing very high currents of up to 100 microA to be achieved per emitter with no significant deviation from the classical Fowler-Nordheim behavior.
Minoux
Eric
E
Thales Research & Technology, Route départementale 128, 91 767 Palaiseau Cedex, France. eric.minoux@thalesgroup.com
Groening
Oliver
O
Teo
Kenneth B K
KB
Dalal
Sharvari H
SH
Gangloff
Laurent
L
Schnell
Jean-Philippe
JP
Hudanski
Ludovic
L
Bu
Ian Y Y
IY
Vincent
Pascal
P
Legagneux
Pierre
P
Amaratunga
Gehan A J
GA
Milne
William I
WI