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A field-effect transistor (FET) having poly(o-methoxyaniline) (POMA) as the active layer was built on a SiO 2 -Si substrate which acts as the gate. The POMA layer was deposited by spin coating on the substrate interdigitated with gold lines and which acts either as the source or drain contact. A tentative theoretical model based on the Schottky gold/polymer interface contact and on the electronic properties of the POMA film was developed to explain the characteristic behavior of the FET device.

Schottky diode structures employing chlorine doped MH-PPV (Methoxy-Hexiloxy-P-Phenylene-Vinylene) as active layers were prepared to study the electronic possibilities of this conjugated polymer. MH-PPV films were deposited by spin-coating technique on ITO (indium tin oxide) coated glass substrates. Aluminum contact was then vacuum evaporated. Dark conductivity characteristic is that of a rectifier diode. Upon illumination the device shows photovoltaic characteristics. When a voltage is applied, however, the structure shows electroluminescence with a peak at 606nm. In this sense, it is a reversible photonic device.

A new type of solar cell based on poly(o-methoxyanilinc)-POMA as active layer is proposed. A simple Schottky structure was prepared: Al/POMA/ITO/glass. The POMA layer was deposited by the casting method and doped with aqueous hydrochloric acid solutions. Light absorption in POMA produces carriers for the electrical current. The dark current vs. voltage curves show a rectification feature. Under illumination, the short circuit current increases with the light intensity, characteristic of the photovoltaic effect. Studies of the dependence on hydrochloric acid concentration, doping time and POMA layer thickness were done. The easy synthesis of POMA and the simplicity of this device arc the important aspects of this structure.

Alternating conductivity measurements of polyaniline, in the 1–10 5 Hz range, were carried out in samples under different temperatures. It was observed that for low frequencies the real component, σ'(ƒ), of ac conductivity is frequency-independent, however obeying the relation σ'(ƒ) ∝ ƒ s , beyond a critical value; the imaginary component increases with frequency in the whole measurements frequency range. The Random Free Energy Barrier Model approach was used to explain the experimental results, and from the theoretical-experimental fittings, it was concluded that the temperature acts in the sense of increasing the carrier mobility.