Influence of surface treatment on cathodoluminescence of CdS single crystals

An investigation was made of local radiative properties of cadmium sulfide tingle crystals subjected to a variety of surface treatments. The investigation was carried out using a scanning electron microscope and apparatus for recording the cathodoluminescence spectra of various parts of a crystal of size was governed by the electron beam diameter (2–10μ). All the investigated crystals emitted luminescence in the exciton part of the spectrum (λ = 495–505 nm) and in the red band region (λ = 680–750 nm) at T= 130°K. When the surface was subjected to mechanical polishing, the red band predominated over the exciton luminescence. A local inhomogeneity of the cathodoluminescence, observed most clearly in the exciton part of the spectrum, was exhibited by all samples irrespective of the surface treatment.