CHARGE-TRANSPORT IN POLY(3-METHYLTHIOPHENE) SCHOTTKY-BARRIER DIODES

Schottky-barrier devices were formed from electropolymerised films of poly (3-methylthiophene) (PMeT). Thermal annealing of a partially undo ped film led to diodes with rectification ratios as high as 5900 at 1 V and 50,000 at 2.5 V and ideality factors slightly above 2. The tempe rature dependence of ac loss tangent and forward currents are identica l suggesting that bulk effects dominate device behaviour even at very low forward voltages. Below 250 K forward currents are essentially ind ependent of temperature. Preliminary TSC measurements show the presenc e of at least two trapping levels in the devices.