摘要
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.
原文 | ???core.languages.en_GB??? |
---|---|
頁(從 - 到) | 1138-1140 |
頁數 | 3 |
期刊 | Applied Physics Letters |
卷 | 80 |
發行號 | 7 |
DOIs | |
出版狀態 | 已出版 - 18 2月 2002 |