c © TÜBİTAK Photo Organic Field Effect Transistor’s Properties

A thin organic films of p-type semiconducting copper phthalocynanine (CuPc) film and semitrans-parent Al film were deposited in sequence by vacuum evaporation on glass substrate with Ag source and drain electrodes, fabricating an organic field effect transistor with metal (aluminum)-semiconductor (copper phthalocyanine) Schottky junction. The transistor was investigated for effect of illumination on its characteristics. It was found that the gate-source (Al-Ag) and gate-drain (also Al-Ag) dark current-voltage characteristics show rectification behavior. Under non-modulated filament-lamp illumination, photo-potential is developed between gate-source and gate-drain terminals. Drain current of this organic phototransistor (OPT) increased with illumination. An energy band diagram of the Al-CuPc junction and the equivalent circuit diagram of the OPT were produced