RT journal article
T1 General route for the decomposition of InAs quantum dots during the capping process
A1 González Robledo, David
A1 Fernández de los Reyes, Daniel
A1 Utrilla, A.D.
A1 Ben Fernández, Teresa
A1 Braza Blanco, María Verónica
A1 Guzman, A.
A1 Hierro, A.
A1 Ulloa, J.M.
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
K1 quantum dots, III–V semiconductors, transmission electron microscopy (TEM)
AB The effect of the capping process on the morphology of InAs/GaAs quantum dots (QDs) by using different GaAs-based capping layers (CLs), ranging from strain reduction layers to strain compensating layers, has been studied by transmission microscopic techniques. For this, we have measured simultaneously the height and diameter in buried and uncapped QDs covering populations of hundreds of QDs that are statistically reliable. First, the uncapped QD population evolves in all cases from a pyramidal shape into a more homogenous distribution of buried QDs with a spherical-dome shape, despite the different mechanisms implicated in the QD capping. Second, the shape of the buried QDs depends only on the final QD size, where the radius of curvature is function of the base diameter independently of the CL composition and growth conditions. An asymmetric evolution of the QDs’ morphology takes place, in which the QD height and base diameter are modified in the amount required to adopt a similar stable shape characterized by a averaged aspect ratio of 0.21. Our results contradict the traditional model of QD material redistribution from the apex to the base and point to a different universal behavior of the overgrowth processes in self-organized InAs QDs.
PB IOP Science
SN 09574484
YR 2016
FD 2016
LK http://hdl.handle.net/10498/30856
UL http://hdl.handle.net/10498/30856
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 07-nov-2026