Fullerene field-effect transistors (FETs) were fabricated with thin films of C-84, which showed n-channel normally-on depletion-type FET characteristics. The C-84 FET device exhibited the highest mobility, mu, of 2.1x10(-3) cm(2) V-1 s(-1) among normally-on fullerene FETs. The carrier transport of this FET device can be interpreted as thermally activated hopping transport. Carrier type (n-channel) and transport mechanism (hopping) reflect the electronic properties of the C-84 molecule. (C) 2004 American Institute of Physics.