Post-growth thermal treatment of self-assembled InAs/GaAs quantumdots
Results of a post-growth rapid thermal annealing (RTA) on GaAs proximity-capped structures with high density ({approx} 1011 cm{sup -2}) of self-assembled InAs/GaAs quantum dots (QDs) are presented. Features due to the QDs, bi-dimensional platelets (2DP) and InAs wetting layer (WL)were identified in photoluminescence (PL) spectrum of the as-grown sample. It is shown, using transmission electron microscopy, that RTA at temperature up to 700 C (for 30's) results in an increase of QDs lateral sizes. After RTA at 800 C or higher temperatures, no QDs can be distinguished and substantial thickening of the WL can be seen. The main PL peak blue shifts as a result of RTA in all investigated temperature ranges, which is accompanied by a quenching of the 2DP and WL PL. It is proposed that the main PL peak, which is due to the QDs in the as-grown sample, results from optical recombination in the modified WL in the samples, after RTA at 800 C and higher temperatures. Laterally-enhanced Ga/In interdiffusion induced by strain is proposed to explain a relatively fast dissolution of QDs copyright 2002 Elsevier Science B.V.All rights reserved.
- Research Organization:
- Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
- Sponsoring Organization:
- USDOE Director. Office of Science. Office of Basic EnergySciences; Center for Excellence CELDIS ICAI-CT-2000-70018, PolishCommittee for Scientific Research Grant 7 T08 A 040 17
- DOE Contract Number:
- AC02-05CH11231
- OSTI ID:
- 861958
- Report Number(s):
- LBNL--52188; BnR: KC0201030
- Journal Information:
- Thin Solid Films, Journal Name: Thin Solid Films Vol. 412; ISSN THSFAP; ISSN 0040-6090
- Country of Publication:
- United States
- Language:
- English
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