Temperature-dependent electroluminescence of stressed and unstressed InAlGaN multi-quantum well UVB LEDs
J. Höpfner1, P. Gupta1, M. Guttmann1, J. Ruschel2, J. Glaab2, T. Kolbe2, J. Rass2, A. Knauer2, C. Stölmacker2, S. Einfeldt2, T. Wernicke1, M. Weyers2, and M. Kneissl1,2
Published in:
Appl. Phys. Lett., vol. 122, no. 15, pp. 151104, doi:10.1063/5.0139200 (2023).
Abstract:
The electroluminescence of UVB light-emitting diodes emitting at 310 nm before and after 1000 h of operation is studied in the temperature range from 20 to 340 K. Before operation, the external quantum efficiency (EQE) at 10 mA gradually increases with decreasing temperature from 0.8% at 340 K to 1.8% at 150 K and then levels off. This trend is attributed to a reduction of non-radiative recombination and finally the domination of radiative recombination at low temperatures. After 1000 h of operation, the EQE has dropped to 0.45% at 340 K with a maximum EQE of 1.4% at 80 K, followed by a drop for temperatures below 80 K. These findings suggest a stress-induced reduction of both the radiative recombination efficiency and the carrier injection efficiency.
1 Institute of Solid State Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
2 Ferdinand-Braun-Institut, Gustav-Kirchhoff-Straße 4, D-12489 Berlin, Germany
Topics:
UV/DUV Light Emitters; Quantum wells; Emission spectroscopy; Heterostructures; Electrical properties and parameters; Superlattices; Light emitting diodes; Quantum efficiency; Photodiodes; Semiconductors; Electroluminescence
Copyright © 2023 Author(s). Published under an exclusive license by AIP Publishing. https://doi.org/10.1063/5.0139200
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