DC conductivity in the thin-films: Al-(Ge-Se-B)-Al structures

Thin films from the Ge-Se-B system have been prepared by vacuum evaporation . The structure and the composition of the films have been investigated usi ng electron microscopy and Auger electron spectroscopy, respectively. The d .c, conductivity of thin-film Al-(GeSe5)(1-x)B-x- Al (0 < x < 20 at.%) samp les has been measured at values of the applied electric fields up to 10(9) V/m at room temperature. From the current-voltage characteristics the value s of the work function of the electron at the Al-GeSeB interface, chi = 0.8 5 eV, the relative dielectric permittivity of the layer, epsilon = 6.72, an d the effective electron mass in the conduction band, m(c)/m = 0.29-0.98 ha ve been derived. The experimental results are in a good agreement with Chri stov's theory for injected electron currents in the insulators. (C) 1999 El sevier Science S.A. All rights reserved.