PRESSURE EFFECT ON THE ELECTRICAL-PROPERTIES OF MANGANESE-DIOXIDE THIN-FILMS

MnO2 thin films are prepared by thermal evaporation technique onto glass substrate at varying deposition pressures. Electrical studies of the films deposited at about 1.99 x 10(-3) Pa show a positive temperature coefficient of resistance (TCR) indicating a metallic characteristics, whereas a negative TCR indicating semiconducting behavior is exhibited by the films deposited at a pressure of about 1.73 x 10(-4) Pa. Thickness dependent electrical conductivity, activation energy, aging effect are also investigated, and the thickness dependent conductivity is well in conformity with the Fuchs-Sondheimer theory. These pressure dependent studies may be of importance for the application of this material in energy efficient surface coating devices.