Single carbon nanotube transistor at GHz frequency.
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 approximately 20 microS is observed on short devices, which meets the best dc results. The capacitance per unit gate length of 60 aF/microm is typical of top gates on a conventional oxide with epsilon approximately 10. This value is a factor of 3-5 below the nanotube quantum capacitance which, according to recent simulations, favors high transit frequencies fT=gm/2piCg. For our smallest devices, we find a large fT approximately 50 GHz with no evidence of saturation in length dependence.
Chaste
J
J
Laboratoire Pierre Aigrain, Ecole Normale Supérieure, 24 rue Lhomond, 75005 Paris, France.
Lechner
L
L
Morfin
P
P
Fève
G
G
Kontos
T
T
Berroir
J-M
JM
Glattli
D C
DC
Happy
H
H
Hakonen
P
P
Plaçais
B
B
D003460:Crystallization / Q000379:methods*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008839:Microelectrodes; D008872:Microwaves; D008968:Molecular Conformation; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D013499:Surface Properties; D014173:Transistors, Electronic
D046911:Macromolecular Substances; D037742:Nanotubes, Carbon