A field-effect transistor (FET) with a channel length of similar to 100 nm
was constructed from a small number of individual V2O5 fibers of the cross
section 1.5 nm x 10 nm. At low temperature, the conductance increases as th
e gate voltage is changed from negative to positive values, characteristic
of a FET with n-type enhancement mode. The carrier mobility, estimated from
the low-field regime, is found to increase from 7.7 x 10(-5) cm(2)/V s at
T = 131 K to 9.6 x 10(-3) cm(2)/V s at T = 192 K with an activation energy
of E-a = 0.18 eV. The nonohmic current/voltage dependence at high electric
fields was analyzed in the frame of small polaron hopping conduction, yield
ing a nearest-neighbor hopping distance of similar to 4 nm. (C) 2000 Americ
an Institute of Physics. [S0003-6951(00)00714-2].