The processes occurring in the surface region of CdS single crystals under electron bombardment,photoexcitation, and gas adsorption and their role in the 80 °K-exciton photoluminescence

Investigations have been carried out in the effect of 3–5 keV electron irradiation, intense photoexcitation, and gas adsorption on photoluminescent spectra of CdS single crystal platelets. CdS platelets subjected to electron bombardment were found to be very active for gas adsorption. The bound exciton emission is influenced by oxygen. A detailed study of the effect of the electron bombardment on the photoluminescence spectra is presented. The results indicate that correlation can be made between the behaviour of the electron bombardment-induced bound exciton emission and the electron processes occurring in the surface region of CdS single crystals. The changes in the photoluminescent spectra caused by the electron bombardment followed by the room temperature photoexcitation, have been interpreted in terms of surface photochemical effects.