Determination of transport parameters in fullerene films

We report the electron and hole drift mobilities and the recombination lifetime in thin polycrystalline C60 films. The data are obtained from photocurrent measurements involving an optical interference grating moving at variable velocity across the sample surface. Considerable degradation of the transport parameters is observed as the samples are exposed to air. The initial values for the electron and hole drift mobilities are 1.3±0.2 cm2/V s and (2±1)×10−4 cm2/V s, respectively, and for the recombination lifetime (1.7±0.2)×10−6 s.