Drift Mobility Measurements in Metal-Free and Lead Phthalocyanine

The drift mobilities of electrons and holes in metal-free and lead phthalocyanine were measured using a transient space-charge-limited-current method and a time-of-flight method. The mobilities were found to be in the range 0.05–0.1 cm2/V·sec for metal-free phthalocyanine and 0.6–4.0 cm2/V·sec for lead phthalocyanine. Fast trapping of carriers in the bulk and emptying of traps at the surface under illumination were observed.