Band-like charge transport in C-60 single crystals

Charge transport properties of vapor grown C-60 Single crystals are investigated in the temperature range from 5-300 K by field-effect transistor and space charge limited current measurements in vacuum. Room temperature mobilities of 2.1 and 1.8 cm(2)/Vs are observed for holes and electrons, respectively. Moreover, the mobilities increase with decreasing temperature following a power law behavior (proportional toT-(1.6)). Values as high as 60 (electrons) and 95 cm(2)/Vs (holes) are achieved at low temperatures. The discontinuity around 255 K is ascribed to the first-order phase transition of C60 The pronounced electric field dependence can be explained by acoustic phonon scattering. Hence, we conclude, that band-like charge transport in delocalized states rather than hopping motion can be assumed as intrinsic charge transport mechanism in undoped C-60.