Carrier recombination dynamics in green InGaN-LEDs with quantum-dot-like structures
Electrical and Computer Engineering
Exciton localization phenomena are considered here to comprehend the high internal quantum efficiency in InGaN/GaN multiple-quantum-well structures having discrete quantum dots (QDs) prepared by metal–organic-chemical-vapor deposition method on c-sapphire substrates. Spectroscopic results from the variable-temperature steady-state-photoluminescence and time-resolved photoluminescence (TRPL) are investigated. While the exciton localization is enhanced by strong localized states within the InGaN/GaN QDs–the impact of free carrier recombination cannot be ignored. The observed non-exponential decay in TRPL measurements is explained using a model by meticulously including localized exciton, non-radiative and free carrier recombination rates. A new method is proposed to calculate the internal quantum efficiency, which is supplementary to the traditional approach based on temperature-dependent photoluminescence measurement.
Journal of Materials Science
Digital Object Identifier (DOI)
Tian, Ming; Ma, Cangmin; Lin, Tao; Liu, Jianping; Talwar, Devki N.; Yang, Hui; Cao, Jiehua; Huang, Xinying; Niu, Wenlong; Ferguson, Ian T.; and Wan, Lingyu, "Carrier recombination dynamics in green InGaN-LEDs with quantum-dot-like structures" (2021). Faculty Publications. 5135.