Field-effect transistor made of individual V2O5 nanofibers

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 the 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, yielding a nearest-neighbor hopping distance of similar to 4 nm. (C) 2000 American Institute of Physics. [S0003-6951(00)00714-2].