Citation
Ulloa Herrero, José María and Anantahanasarn, S. and Van Veldhoven, P.J and Koenraad, P.M. and Nötzel, R.
(2008).
Influence of an ultrathin GaAs interlayer on the structural properties of InAs/InGaAsP/InP (100) quantum dots investigated by cross-sectional scanning tunneling microscopy.
"Applied Physics Letters", v. 92
(n. 8);
pp..
ISSN 0003-6951.
https://doi.org/10.1063/1.2884692.
Abstract
Cross-sectional scanning tunneling microscopy is used to study at the atomic scale how the structural properties of InAsInGaAsPInP quantum dots _QDs_ are modified when an ultrathin _0–1.5 ML_ GaAs interlayer is inserted underneath the QDs. Deposition of the GaAs interlayer suppresses the influence of the AsP exchange reaction on QD formation and leads to a planarized QD growth surface. A shape transition from quantum dashes, which are strongly dissolved during capping, to well defined QDs takes place when increasing the GaAs interlayer thickness between 0 and 1.0 ML. Moreover, the GaAs interlayer allows the control of the AsP exchange reaction, reducing the QD height for increased GaAs thicknesses above 1.0 ML, and decreases the QD composition intermixing, producing almost pure InAs QDs.
