Mechanisms of light emission from terbium ions (Tb3+) embedded in a Si rich silicon oxide matrix

Abstract Mechanisms of light emission in Tb doped Si rich SiO x matrix prepared by magnetron sputtering are studied by photoluminescence spectroscopy (PL). Characteristic PL peaks of Tb 3+ ions and Si nanocrystals are simultaneously observed with an inverse relationship between their intensity. With a prolonged heat treatment at high temperatures, light emission from Tb 3+ ions enhances at the expense of total quenching of the PL signal from the nanocrystals. It is suggested from the annealing studies as a function of process conditions and structural characterization that the light emission from Tb ions is mediated by trap states formed in the band gap of the oxide matrix by Tb x Si y O z complexes or excess Si states.