p-Channel Field-Effect Transistors Based on C60 Doped with Molybdenum Trioxide

Fullerene (C-60) is a well-known n-channel organic semiconductor. We demonstrate that p-channel C-60 field-effect transistors are possible by doping with molybdenum trioxide (MoO3). The device performance of the p-channel C-60 field-effect transistors, such as mobility, threshold voltage, and on/off ratio is varied in a controlled manner by changing doping concentration. This work demonstrates the utility of charge transfer doping to obtain both n- and p-channel field-effect transistors with a single organic semiconductor.