Structural and optical properties of alkali halide multilayer LiF:NaF films

Alkali halide multilayer films containing a large concentration of color centers created by low energy (3–12 keV) electron beams in a thin dielectric layer of controlled depth, represent a good and simple way to obtain new optically active materials. This work presents a study of multilayer LiF:NaF films, grown by physical evaporation. The structural and morphological characterization of the samples have been performed using x-ray diffraction, scanning electron microscopy, atomic force microscopy, and x-ray photoemission spectroscopy depth profile techniques. The visible photoluminescence of optically active defects was measured by excitation with an Argon laser. Controlling the deposition and coloration parameters it is possible to obtain new photoluminescent materials with predesigned optical features.