Efficient Auger-excitation of erbium electroluminescence in reversely-biased silicon structures

In p-n junctions based on c-Si:Er, we have observed strongly efficient exci tation of erbium electroluminescence at 1.54 mu m. Excitation of erbium ion s is accompanied by strong recombination of free carriers indicating a part icipation of an Auger mechanism. A possible excitation mechanism is propose d which is the Auger recombination of electrons occupying the upper subband of the conduction band with free holes in the valence band, whereas the en ergy of the recombination process is transferred by Coulomb interaction to 4f electrons of an erbium ion transmitting it to the second excited state I -4(11/2) (excitation energy 1.26 eV). The observed three-level excitation o f erbium ions is promising for the development of a Si:Er laser. (C) 1999 A merican Institute of Physics. [S0003-6951(99)04343-0].