Effect of composition inhomogeneity on the photoluminescence of InGaN/GaN multiple quantum wells upon thermal annealing

Chang Cheng Chuo, Mao Nan Chang, Fu Ming Pan, Chia Ming Lee, Jen Inn Chyi

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

The optical properties of thermally annealed InGaN/GaN multiple quantum wells were investigated by low-temperature photoluminescence measurements. It is found that the photoluminescence peak exhibits a redshift followed by a blueshift as the annealing time is increased. In contrast, the assigned photoluminescence peak from an In-rich dot-like structure shows a monotonic blueshift with more annealing time. Transmission electron microscopic observation confirms that the density of dot-like structures is reduced after thermal annealing, indicating that phase separation does not take place in these samples. Instead, in-plane and out-plane outdiffusion of dot-like structures is proposed to account for the spectral shift with more annealing time. Based on this diffusion model, a quantized state transition in the quantum well along with the composition inhomogeneity and piezoelectric field is considered to be the dominant luminescence mechanism.

Original languageEnglish
Pages (from-to)1138-1140
Number of pages3
JournalApplied Physics Letters
Volume80
Issue number7
DOIs
StatePublished - 18 Feb 2002

Fingerprint

Dive into the research topics of 'Effect of composition inhomogeneity on the photoluminescence of InGaN/GaN multiple quantum wells upon thermal annealing'. Together they form a unique fingerprint.

Cite this