MOBILITY OF CHARGE-CARRIERS IN VAPOR-PHASE GROWN C-60 SINGLE-CRYSTAL

Transport properties of charge carriers in the fullerene C60 single crystal grown from the vapor phase were studied by using the time-of-flight technique, and absolute values of mobility for electrons mu(e) = 0.5+/-0.2 cm2/V s, and holes mu(h) = 1.7+/-0.2 cm2/V s at room temperature were measured. Crystals were characterized as having about 3 x 10(13) cm-3 deep trapping sites for holes. The temperature dependence of mu(h) was measured over a broad temperature range. Two features were revealed: (i) a step-wise increase of the mobility below the phase-transition and (ii) almost temperature independence of mobility in the regions 50-200 and 250-310 K.