Can misfit dislocations be located above the interface of InAs/GaAs (001) epitaxial quantum dots?

Nanoscale Res Lett

School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia.

Published: August 2012

InAs/GaAs(001) quantum dots grown by droplet epitaxy were investigated using electron microscopy. Misfit dislocations in relaxed InAs/GaAs(001) islands were found to be located approximately 2 nm above the crystalline sample surface, which provides an impression that the misfit dislocations did not form at the island/substrate interface. However, detailed microscopy data analysis indicates that the observation is in fact an artefact caused by the surface oxidation of the material that resulted in substrate surface moving down about 2 nm. As such, caution is needed in explaining the observed interfacial structure.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3494528PMC
http://dx.doi.org/10.1186/1556-276X-7-486DOI Listing

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