Nonradiative energy back transfer from erbium in silicon by impurity Auger process

Abstract

The investigations of the temperature dependence of intensity and decay time of the photoluminescence of Erbium in silicon show that the luminescence quenching is caused by a nonradiative energy back transfer from the excited Erbium. The electroluminescence decay is studied by applying different bias conditions during the decay. In a two-beam experiment the PL decay is monitored for different background excitation laser powers. The observed changes of the decay time are a strong evidence for the impurity auger effect as an efficient luminescence quenching mechanism of erbium in silicon. It is also shown that the fast initial luminescence decay component is related to the quenching by excess carriers. The power dependence, the decay profiles with two components and the two-beam experiment can be simulated by solving a set of rate equations considering the formation of excitons, the decrease of pumping efficiency by exciton auger recombination and the decrease of radiation efficiency by the impurity auger effect with free electrons.