Direct observation of light-absorbing nanocrystals in glass matrices by the projection laser photoion microscopy technique

Abstract

This article reports on the achievement of actual laser (spectral) selectivity in the field ion microscopy technique: when irradiating needle tips fabricated from heat-treated red light-filter glass by radiation from a copper vapor laser, light-absorbing CdSxSe1−x nanocrystallites present in the transparent glass matrix were registered in the form of bright spots against a dark background in photoion images. Mean radii of the observed nanocrystallites are equal to 10–15 nm which corresponds well to sizes being anticipated due to the heat treating conditions. Masses of the ions desorbed also indicated on the evaporation of rather heavy Cd, CdS, or analogous ions rather than light Si and analogous ions which should be typical for the laser-induced field evaporation of the transparent glass.