Temperature and excitation power dependent photoluminescence intensity of GaInN quantum wells with varying charge carrier wave function overlap
C. Netzel1, V. Hoffmann1, T. Wernicke1, A. Knauer1, M. Weyers1, M. Kneissl1,2, and N. Szabo3
Published in:
J. Appl. Phys., vol. 107, no. 033510 (2010).
Abstract:
For the realization and the improvement of GaN-based optoelectronic devices (light emitting diodes and laser diodes) emitting from the ultraviolet to the red wavelength range GaInN quantum well structures with high internal quantum efficiency are of great importance. To determine parameters which affect the internal quantum efficiency, we have analyzed the emission intensity of GaInN quantum well structures with varied electron and hole wave function overlap by temperature and excitation power dependent and by time-resolved photoluminescence. The quantum confined Stark effect reduces the temperature dependent photoluminescence emission intensity for thick polar quantum wells at low temperature. But near room temperature, these thick polar GaInN quantum wells feature less relative intensity loss than thinner polar quantum wells. This behavior can partially be assigned to increased screening effects and higher quantum well barriers for thicker quantum wells. Additionally, excitation power dependent photoluminescence points to a transition from a radiative recombination based on excitons at 10 K to a bimolecular recombination at room temperature for thick c-plane quantum wells. This transition may also affect the intensity decrease by a changed carrier diffusivity.
1 Ferdinand-Braun-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany
2 Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany
3 Helmholtz Zentrum Berlin, Glienicker Strasse 100, 14109 Berlin, Germany
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