InGaN quantum dots with short exciton lifetimes grown on polar c-plane by metal-organic chemical vapor deposition

An investigation of self-assembled polar InGaN quantum dots (QDs) on c-plane sapphire substrates by metal-organic chemical vapor deposition (MOCVD) is reported. The radiative exciton lifetime is measured by time-resolved photoluminescence at a low temperature of 18 K, where the non-radiative recombi...

Full description

Bibliographic Details
Published in:Materials Research Express
Main Authors: Chunyu Zhao, Chak Wah Tang, Guanghui Cheng, Jiannong Wang, Kei May Lau
Format: Article
Language:English
Published: IOP Publishing 2020-01-01
Subjects:
quantum dots
MOCVD
InGaN
lifetime
Online Access:https://doi.org/10.1088/2053-1591/abcac2
Description
Summary:An investigation of self-assembled polar InGaN quantum dots (QDs) on c-plane sapphire substrates by metal-organic chemical vapor deposition (MOCVD) is reported. The radiative exciton lifetime is measured by time-resolved photoluminescence at a low temperature of 18 K, where the non-radiative recombination can be negligible. A mono-exponential exciton decay with a radiative exciton lifetime of 480 ps for uncapped QDs is revealed. With an optimized GaN capping layer grown by a two-step method, a radiative exciton lifetime of 707 ps for the capped QDs is preserved. The short radiative exciton lifetime is much shorter than that for previously studied polar QDs and is even comparable with those grown along non-polar QDs, which is strong evidence of the reduction of built-in fields in these polar InGaN QDs.
ISSN:2053-1591

Similar Items