Title
Carrier recombination dynamics in green InGaN-LEDs with quantum-dot-like structures
Department
Electrical and Computer Engineering
Document Type
Article
Publication Date
1-1-2021
Abstract
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 Title
Journal of Materials Science
Journal ISSN
00222461
Volume
56
Issue
2
First Page
1481
Last Page
1491
Digital Object Identifier (DOI)
10.1007/s10853-020-05343-6