Effect of Sn doping on photoconductivity in amorphous As2Se3 and AsSe films

The kinetics of transient photocurrents in tin-doped a-As2Se3 and a-AsSe films are found to be strongly dependent on the light intensity and temperature, as well as on the glass composition and tin concentration. The experimental results are interpreted in terms of the multiple-trapping model with the photoconductivity kinetics determined by trap-controlled recombination. The shape of the photocurrent transients was found to be mainly controlled by deep carrier trapping, whereby the energy distribution and concentration of the deep traps is determined by the structure and composition of the doped amorphous films.