Dominant carrier recombination mechanisms in GaInNAs/GaAs quantum well light-emitting diodes
Résumé
The electroluminescence of GaInNAs/GaAs quantum well light-emitting diodes is analyzed as a function of temperature and injection current. The relative influence of nonradiative carrier recombination, recombination from localized states, and conduction-band to valence-band recombination is discussed. The localized states are found to dominate the emission and the external quantum efficiency only at low temperatures and currents. When temperature and/or injection level are increased, band-to-band transitions become the main recombination mechanism. Nonradiative recombination is strongly thermally activated, and becomes the dominant process above 75 K. As a result of postgrowth rapid thermal annealing, the device luminescence efficiency increases by over one order of magnitude due to a decrease in the density of nonradiative recombination centers.