Effect of Heat Treatment Conditions on Photo sensitivity of CdSe<sub><i>x</i></sub>S<sub>1-<i>x</i></sub> Polycrystalline Films
Abstract
The influence of thermal treatment on the lux-ampere characteristics of polycrystalline films from the CdSexS1-x solid solution obtained by the method of thermal evaporation in a vacuum has been investigated. It is shown that at low illumination intensities L μ of electrons increases with a power law μ ~ Lγ, first with the exponent γ > 1, then with γ ≈ 0.5, and their concentration n almost does not change. Starting from the intensity L > 12 - 15 lx, the electron concentration increases strongly n ~ Lβ from β ≈ 3.0, and the parameters n and μ reach relatively high values ~(1015 - 1016) sm-3 and ~(150 - 200) sm2/V·s, however further, at L > 50 lx, a weak dependence of n(L) and μ(L) with β, γ < 1.0 is found. The obtained experimental results are interpreted on the basis of a model of a semiconductor film with intergranular potential barriers when the concentration and barrier mechanisms of photoconductivity operate simultaneously.