Photosensitivity and spectra of deep local states in sintered films of cadmium selenide and cadmium telluride alloys

The photoconductive and luminescence properties of non-intentionally doped and copper-doped CdSe x Te 1− x ( x=0−1) films were studied. The films were prepared by spraying an aqueous suspension of mixtures with varying composition onto ceramic substrate. Both the energy gaps determined using photoconductivity spectra and the maxima of the luminescence bands as functions of the film composition x were obtained. The correlation of the luminescence intensity and the photoconductivity with x was established. Using the decay curves of photocurrent excited under “light impact” conditions the electron capture cross-sections of the recombination centres in the films under investigation were estimated. The nature of the recombination centres in CdSe x Te 1− x ( x=0–1) films both copper free and copper doped are discussed.