Showing papers by "V. Damodara Das published in 1985"
TL;DR: In this article, the authors measured the resistance of lead telluride and lead selenide films at different air pressures and found that resistance of the as-grown films was of the order of a kilohm but increased with increasing pressure.
Abstract: Lead telluride and lead selenide films were prepared by the thermal evaporation technique on clean glass substrates held at room temperature in a vacuum of 3\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$ Torr. The resistance of the films was measured at different air pressures. The resistance of the as-grown films was found to be of the order of a kilohm but increased with increasing pressure. A resistance maximum was observed at a particular air pressure after which the resistance decreased with increasing pressure. An indirect method, namely, the measurement of the conductivity variation as a function of air pressure, has been used to estimate the extent of air adsorption and the adsorption isotherms have been drawn on this basis. The dependence of adsorption on thickness is also discussed.
20 citations
TL;DR: In this paper, the size-dependent phase transition is explained by taking into account the varying surface and intergrain surface energy contributions to the total energy of the stable phase as a function of thickness and the difference in specific surface and integrain surface energies of the two phases.
19 citations