(In)AlGaN deep ultraviolet light emitting diodes with optimized quantum well width

T. Kolbe1, T. Sembdner1, A. Knauer2, V. Kueller2, H. Rodriguez2, S. Einfeldt2, P. Vogt1, M. Weyers2, and M. Kneissl1,2

1 Institute of Solid State Physics, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany
2 Ferdinand-Braun-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, D-12489 Berlin, Germany

Published in:
phys. stat. sol. (a), vol. 207, no. 9, pp. 2198-2200 (2010).
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Abstract:
The effect of the quantum well (QW) width on the light output and efficiency of ultraviolet (UV) light emitting diodes (LEDs) has been investigated. The carrier injection in the devices is simulated and compared with electroluminescence (EL) measurements. The light output power depends clearly on the QWthickness. The highest output power has been found for the LEDs with aQWthickness of 2.2 nm. This effect is attributed to the trade-off between electron and hole wave function overlap and carrier concentration in the active region which are triggered by the quantum confined Stark effect.

Keywords:
electroluminescence, InGaAlN, light emitting diodes, quantum wells

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