Thermally assisted tunnelling in ambipolar field-effect transistors based on fullerene peapod bundles

We report the first detailed studies of the electrical transport behaviour of C-70 fullerene peapod bundles at various temperatures from 400 K down to 4 K. With electrical breakdown, we have prepared ambipolar (i.e. both p- and n-type) field-effect transistors (FETs) using fullerene peapod bundles with high levels of performance. This paper focuses on the role of the Schottky barrier and the thermal activation energy in the transport behaviour of fullerene bundles. The temperature dependence of our measurements reveals that transport is dominated by thermally assisted tunnelling in fullerene bundles at low temperature.