Single carbon nanotube transistor at GHz frequency
Résumé
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]
Origine : Fichiers produits par l'(les) auteur(s)