X-ray determination of vertical ordering of InAs quantum dots in InAs/GaAs multilayers

González, J. C.; Magalha˜es-Paniago, R.; Rodrigues, W. N.; Malachias, A.; Moreira, M. V. B.; de Oliveira, A. G.; Mazzaro, I.; Cusatis, C.; Metzger, T. H.; Peisl, J.
February 2001
Applied Physics Letters;2/19/2001, Vol. 78 Issue 8, p1056
Academic Journal
The degree of vertical alignment of InAs quantum dots in InAs/GaAs(001) multilayers was studied using grazing incidence x-ray scattering. We show that it is necessary to access one of the weak (200) x-ray reflections to observe the modulation of the GaAs lattice periodicity produced by the stacking of the InAs dots. The degree of alignment of the dots was assessed by fitting the x-ray diffuse scattering profiles near a GaAs (200) reciprocal lattice point. By using a model of gaussian lateral displacement of the dots, we show that we can determine the average value of the mistake in stacking positions of the islands from one bilayer to the next. © 2001 American Institute of Physics.


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