Optical power degradation mechanisms in 271â
nm AlGaN-based deep ultraviolet light-emitting diodes.
Opt Express
; 31(12): 20265-20273, 2023 Jun 05.
Article
em En
| MEDLINE
| ID: mdl-37381425
ABSTRACT
The degradation of AlGaN-based UVC LEDs under constant temperature and constant current stress for up to 500 hrs was analyzed in this work. During each degradation stage, the two-dimensional (2D) thermal distributions, I-V curves, optical powers, combining with focused ion beam and scanning electron microscope (FIB/SEM), were thoroughly tested and analyzed the properties and failure mechanisms of UVC LEDs. The results show that 1) the opto-electrical characteristics measured before/during stress indicate that the increased leakage current and the generation of stress-induced defects increase the non-radiative recombination in the early stress stage, resulting in a decrease in optical power; 2) the increase of temperature caused by the deterioration of the Cr/Al layer of p-metal after 48 hrs of stress aggravates the optical power in UVC LEDs. The 2D thermal distribution in conjunction with FIB/SEM provide a fast and visual way to precisely locate and analyze the failure mechanisms of UVC LEDs.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article