Excitation of erbium in the heterogeneous nanocrystalline matrix of amorphous silicon

The erbium photoluminescence decay kinetics at a wavelength of 1.54 μm in amorphous hydrogenated silicon films obtained at high oxygen concentrations in a magnetron gas discharge is investigated. Optically active erbium is found to exist both in the semiconducting matrix of amorphous silicon and in dielectric nanocrystals of erbium silicate, which are formed in this case. The concentration ratio of excited erbium in amorphous silicon and in the nanocrystals is determined, as well as the time of excitation transfer from erbium in amorphous silicon to erbium in the nanocrystals. The mechanism of erbium excitation in this heterogeneous system is considered. The external quantum yield of erbium photoluminescence measured at a wavelength of 1.54 μm and room temperature is found to be 0.3–0.4%.