We describe a pulsed measurement technique to suppress hysteresis for carbon nanotube (CNT) device measurements in air, vacuum, and over a wide temperature range (80-453 K). Varying the gate pulse width and duty cycle probes the relaxation times associated with charge trapping near the CNT, found to be up to the 0.1-10 s range. Longer off times between voltage pulses enable consistent, hysteresis-free measurements of CNT mobility. A tunneling front model for charge trapping and relaxation is also described, suggesting trap depths up to 4-8 nm for CNTs on SiO2. Pulsed measurements will also be applicable to other nanoscale devices such as graphene, nanowires, and molecular electronics, and could enable probing trap relaxation times in a variety of material system interfaces.
@article{arxiv.0909.4104,
title = {Reduction of Hysteresis for Carbon Nanotube Mobility Measurements Using Pulsed Characterization},
author = {David Estrada and Sumit Dutta and Albert Liao and Eric Pop},
journal= {arXiv preprint arXiv:0909.4104},
year = {2010}
}