Optimizing the GaAs capping layer growth of 1.3 mu m InAs/GaAs quantum dots by a combined two-temperature and annealing process at low temperatures
Data(s) |
2008
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Resumo |
We report on optimizing the GaAs capping layer growth of 1.3 mu m InAs quantum dots (QDs) by a combined two-temperature and annealing process at low temperatures using metalorganic chemical vapor deposition. The initial part (tnm) of the capping layer is deposited at a low temperature of 500 degrees C, which is the same for the growth of both the QDs and a 5-nm-thick In0.15Ga0.85As strain-reducing capping layer on the QDs, while the remaining part is grown at a higher temperature of 560 degrees C after a rapid temperature rise and subsequent annealing period at this temperature. The capping layer is deposited at the low temperatures (<= 560 degrees C) to avoid postgrowth annealing effect that can blueshift the emission wavelength of the QDs. We demonstrate the existence of an optimum t (=5 nm) and a critical annealing time (>= 450s) during the capping, resulting in significantly enhanced photoluminescence from the QDs. This significant enhancement in photoluminescence is attributed to a dramatic reduction of defects due to the optimized capping growth. The technique reported here has important implications for realizing stacked 1.3 mu m InAs/GaAs QD lasers. (C) 2008 Elsevier B.V. All rights reserved. |
Identificador | |
Idioma(s) |
英语 |
Fonte |
Yang T ; Nishioka M ; Arakawa Y .Optimizing the GaAs capping layer growth of 1.3 mu m InAs/GaAs quantum dots by a combined two-temperature and annealing process at low temperatures ,JOURNAL OF CRYSTAL GROWTH,2008 ,310(24):5469-5472 |
Palavras-Chave | #半导体材料 #Metalorganic chemical vapor deposition #Quantum dots #InAs #GaAs #Laser diodes |
Tipo |
期刊论文 |