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arXiv · 0806.0227

Single Carbon Nanotube Transistor at GHz Frequency

Julien Chaste·Lorenz Lechner·Pascal Morfin·Gwendal Feve·Takis Kontos·Jean-Marc Berroir·Christian Glattli·Henri Happy·Perti Hakonen·Bernard Placais
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Abstract

We report on microwave operation of top-gated single carbon nanotube transistors. From transmission measurements in the 0.1-1.6 GHz range, we deduce device transconductance gm and gate-nanotube capacitance Cg of micro- and nanometric devices. A large and frequency-independent gm of about 20 microSiemens is observed on short devices, which meets the best dc results. The capacitance per unit gate length of 60 aF/micrometer is typical of top gates on a conventional oxide with a dielectric constant equal to 10. This value is a factor of 3-5 below the nanotube quantum capacitance which, according to recent simulations, favors high transit frequencies . For our smallest devices, we find a large transit frequency equal to 50 GHz with no evidence of saturation in length dependence.

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Julien Chaste, Lorenz Lechner, Pascal Morfin, Gwendal Feve, Takis Kontos, Jean-Marc Berroir, Christian Glattli, Henri Happy, Perti Hakonen, Bernard Placais. 2008-06-02. Single Carbon Nanotube Transistor at GHz Frequency. https://doi.org/10.1021/nl0727361

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