Electrical conduction and photoconduction in Se_{80−<i>x</i>}Te₂₀Bi_<i>x</i>thin films

Abstract

The dark conductivity and photoconductivity of Se80−xTe20Bix (0≤x≤1) thin films have been studied. The values of dc activation energy, optical band gap and photoconduction activation energy are found to decrease with the addition of bismuth content. The optical energy gap has been found to be approximately equal to twice the dark thermal activation energy in all the compositions studied. The variation of photocurrent with illumination intensity indicates that the recombination mechanism is bimolecular.