Fabrication and characterization of field-effect transistor device with C2v isomer of Pr@C82

A field-effect transistor (FET) device was fabricated with thin films of C2v isomer of Pr@C82. This device apparently showed n-channel normally on type FET properties, where non-zero current was observed at the gate-source voltage, VGS, of 0 V. Normally off FET properties were observed by subtraction of the non-zero current from the drain current. Thus the normally on properties are ascribed to the high bulk current caused by the small energy gap of ≈0.3 eV. The field-effect mobility for this FET was 1.5 × 10−4 cm2 V−1 s−1 at 320 K, being comparable to those of other endohedral metallofullerene FET devices.