ELECTRICAL CHARACTERISTICS OF AU-PBPC-AU THIN-FILM SANDWICH DEVICES ON EXPOSURE TO O-2 AND CO(2)

The semiconducting characteristics of Au-PbPc-Au thin film sandwich de vices were studied as a function of exposure to oxygen (in the form of air) and chlorine. Both O2 and Cl2 were found to generate acceptor le vels within the PbPc bandgap. Both ohmic and space charge-limited cond uction were observed. The experimental data were analysed within the f ramework of the model of Schmidlin and Roberts. Devices exposed to air for extended periods showed Schottky behaviour. The width of the Scho ttky barrier was estimated as 60 nm, the barrier height 1.5 eV and the rectifying ratio at +/-1 V was 200. The Schottky barrier disappeared after vacuum annealing at 423 K.