Optical characterization of point defects on internal quantum efficiency in AlGaN quantum wells grown on face-to-face-annealed sputtered AlN templates

Autor: Satoshi Kurai, Megumi Fujii, Yuta Ohnishi, Ryota Oshimura, Kosuke Inai, Kunio Himeno, Narihito Okada, Kenjiro Uesugi, Hideto Miyake, Yoichi Yamada
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: AIP Advances, Vol 13, Iss 4, Pp 045319-045319-7 (2023)
Druh dokumentu: article
ISSN: 2158-3226
DOI: 10.1063/5.0145131
Popis: The correlation between the internal quantum efficiency (IQE) and the effective diffusion length estimated by the cathodoluminescence intensity line profile near the dark spots, including the effect of non-radiative recombination due to point defects, was experimentally clarified for AlGaN multiple quantum wells (MQWs) on face-to-face annealed (FFA) sputter-deposited AlN templates with different IQEs and similar dislocation densities. The IQEs, which were determined by temperature- and excitation-power-dependent photoluminescence measurements, were independent of the dark spot densities and increased with increasing effective diffusion length (Leff) estimated from the cathodoluminescence line profile analysis. These results suggested that the IQEs of the MQW/FFA samples were governed by the point defect density. The fitting results for the relationship between IQE and Leff and for that between IQE and Cmax explained the experimental results qualitatively.
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