Luminescence decay of the 1.54 μm emission from erbium in silicon

Photoluminescence of silicon implanted with erbium and oxygen was measured in the time domain focussing on the temperature and excitation density dependence of the intra-4f-shell emission from Er³⁺. The decay of this luminescence is similar for the different optically active crystal field split Er-centres. At low temperatures the luminescence transients consist of a fast initial non-exponential component followed by slower exponential behaviour. An increase in excitation density results in a higher proportion of the luminescence decaying with the faster decay time. Our results indicate a relation of the fast component to nonradiative processes. Auger recombination is proposed as a possible mechanism.