Optimisation of MBE growth conditions for InAs quantum dots on (001) GaAs for 1.3 μm luminescence
Journal article, 2001
We present a study of the optimised growth conditions for InAs quantum dots (QDs) grown on GaAs substrates by solid source molecular beam epitaxy (SSMBE). Growth conditions for best luminescence intensity and linewidth were found within narrow windows of substrate temperature (500-520°C) and nominal InAs layer thickness (3.3-3.7 monolayers). The emission wavelength of such InAs QDs capped by GaAs was around 1.24 ?m. However, this is redshifted to 1.3 ?m or more by capping the InAs QDs with a thin layer of InxGa1-xAs. The results show that both In content and thickness of the capping layer can be used to tune the emission wavelength. Atomic force microscopy images show that the surface recovers to two-dimensional when depositing In0.2Ga0.8As while remaining three-dimensional when depositing In0.4Ga0.6As.
semiconductor quantum dots
molecular beam epitaxial growth
spectral line intensity
semiconductor epitaxial layers
gallium arsenide
photoluminescence
semiconductor growth
III-V semiconductors
red shift
atomic force microscopy
optimisation
indium compounds
spectral line breadth
Author
Fariba Ferdos
Department of Microelectronics
Mahdad Sadeghi
Department of Microelectronics
Qing Xiang Zhao
Chalmers, Physical Electronics and Photonics
Shu Min Wang
Department of Microelectronics
Anders Larsson
Department of Microelectronics
Journal of Crystal Growth
0022-0248 (ISSN)
Vol. 227-228 1140-5Subject Categories
Telecommunications
Condensed Matter Physics
DOI
10.1016/S0022-0248(01)01003-X