AC CONDUCTION AND DIELECTRIC CHARACTERIZATION OF LEAD SELENIDE THIN FILMS FROM VACUUM EVAPORATION TECHNIQUE

Thin films of PbSe are prepared by vacuum deposition technique on to well cleaned glass substrates. The film thicknesses are measured by quartz crystal monitor method. Thin film capacitors of the type (Al-PbSe-Al) have been fabricated. AC Conduction and Dielectric studies performed on a stabilized samples of thickness 1000 angstrom and 2000 angstrom at various frequencies (20Hz-100KHz) and temperatures (303K-483K). From the AC conduction studies, it is confirmed that the mechanism responsible for the conduction process is hopping. Thermal activation energy is found to decrease with increase in film thickness. The variations of the dielectric constant and loss as function of frequency at different temperature are observed and the results are discussed. Temperature co-efficient of capacitance and permittivity are evaluated.