Fabrication and characterization of field-effect transistor device with C_<2v> isomer of Pr@C_<82>

Endohedral metallofullerene field-effect transistor (FET) device was fabricated with thin films of C_ isomer of Pr@C_. This device showed n-channel normally-on type FET properties, where high bulk current of Pr@C_ was observed at gate voltage of 0 V. The mobility, μ, was estimated to be 1.5 x 10^ cm^2 V^ s^ at 320 K, which is comparable to those of other endohedral metallofullerene FET devices. The normally-on properties have been found to originate from the high bulk current caused by the small energy gap of Pr@C_