We use impedance spectroscopy to measure the high frequency properties of single-walled carbon nanotube field effect transistors (swCN-FETs). Furthermore, we extend Scanning Gate Microscopy (SGM) to frequencies up to 15MHz, and use it to image changes in the impedance of swCN-FET circuits induced by the SGM-tip gate. In contrast to earlier reports, the results of both experiments are consistent with a simple RC parallel circuit model of the swCN-FET, with a time constant of 0.3 ms. We also use the SGM tip to show the local nature of the memory effect normally observed in swCN-FETs, implying that nanotube-based memory cells can be miniaturized to dimensions of the order of tens of nm.
@article{arxiv.cond-mat/0504534,
title = {High frequency Scanning Gate Microscopy and local memory effect of carbon nanotube transistors},
author = {Cristian Staii and Rui Shao and Dawn A. Bonnell and Alan T. Johnson},
journal= {arXiv preprint arXiv:cond-mat/0504534},
year = {2007}
}