Effective Auger excitation of erbium luminescence by hot electrons in silicon

In an electroluminescent structure based on erbium-doped crystalline silico n we have found and studied a new mechanism of excitation of erbium ions in volving Auger recombination of electrons from the upper subband of the cond uction band with holes from the valence band. The new excitation mechanism is weak at low temperatures, but it is resonantly enhanced at 160 K, when t he energy distance of the edge of the upper subband of the conduction band from the valence band edge coincides with the energy of the second excited state of the erbium ion due to temperature shrinking of the silicon energy gap. (C) 1999 Elsevier Science B.V. All rights reserved,