Single carbon nanotube transistor at GHz frequency

J. Chaste , L. Lechner , P. Morfin , G. Feve , T. Kontos , J.M. Berroir , D.C. Glattli , H. Happy , P. Hakonen , B. Placais

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 gatenanotube capacitance Cg of micro- and nanometric devices. A large and frequency-independent gm ∼ 20 µS is observed on short devices which meets best dc results. The capacitance per unit gate length ∼ 60 aF/µm is typical of top gates on conventional oxide with ǫ ∼ 10. This value is a factor 3–5 below the nanotube quantum capacitance which, according to recent simulations, favors high transit frequencies fT = gm/2πCg. For our smallest devices, we find a large fT ∼ 50 GHz with no evidence of saturation in length dependence

Domaines: Physique [physics]

J. Chaste, L. Lechner, P. Morfin, G. Feve, T. Kontos, et al.. Single carbon nanotube transistor at GHz frequency. Nano Letters, 2008, 8, pp.525-528. ⟨10.1021/nl0727361⟩. ⟨hal-00356662⟩