Ahmad Kamarudin, Mazliana and Hayne, Manus and Zhuang, Q. D. and Kolosov, Oleg and Nuytten, Thomas and Moshchalkov, V. V. and Dinelli, F. (2010) GaSb quantum dot morphology for different growth temperatures and the dissolution effect of the GaAs capping layer. Journal of Physics D: Applied Physics, 43 (6). 065402. ISSN 0022-3727
Full text not available from this repository.Abstract
We compare the characteristics of GaSb quantum dots (QDs) grown by molecular beam epitaxy on GaAs at temperatures from 400°C to 490°C. The dot morphology, in terms of size, shape and density, as determined by atomic force microscopy on uncapped QDs, was found to be highly sensitive to the growth temperature. Photoluminescence spectra of capped QDs are also strongly dependent on growth temperature, but for samples with the highest dot density, where the QD luminescence would be expected to be the most intense, it is absent. We attribute this to dissolution of the dots by the capping layer. This explanation is confirmed by atomic force microscopy of a sample that is thinly capped at 490°C. Deposition of the capping layer at low temperature resolves this problem, resulting in strong QD photoluminescence from a sample with a high dot-density.