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High frequency Scanning Gate Microscopy and local memory effect of carbon nanotube transistors

Cristian Staii·Rui Shao·Dawn A. Bonnell·Alan T. Johnson Jr
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Abstract

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.

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Cristian Staii, Rui Shao, Dawn A. Bonnell, Alan T. Johnson Jr. 2005-04-22. High frequency Scanning Gate Microscopy and local memory effect of carbon nanotube transistors. https://doi.org/10.1021/nl050316a

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