Photoelectrical Properties in Thin Films of (Ge20se80)0.98sn0.02 Glassy Alloy

Abstract

Electrical measurements have been made in thin films (Ge20Se80)0.98Sn0.02 glassy alloy as a function of temperature and intensity. Dark conductivity (sd) and photoconductivity (sph) measurements show that the conduction in this glassy alloy is an activated process having single activation energy in the measured temperature range (289 K to 333 K). Intensity dependence of photoconductivity (sph) follows a power law with intensity (F), s Fg ph µ .The value of g has been found nearly 0.5, suggesting bimolecular recombination. Rise and decay of photocurrent at different temperatures, intensities and illumination times show that photocurrent rises monotonically to the steady state value and the decay of photocurrent is quite slow. Analysis of photoconductive decay shows that the recombination within localized states may be predominant recombination mechanism in this glassy system.