So. Ferreira et al., AFM characterization of PbTe quantum dots grown by molecular beam epitaxy under Volmer-Weber mode, J CRYST GR, 231(1-2), 2001, pp. 121-128
PbTe quantum dots (QD) were fabricated on BaF2(1 1 1) substrates by molecul
ar beam epitaxy under Volmer-Weber (V-W) growth mode. The morphological asp
ects of the samples were characterized using atomic force microscopy-AFM. I
n contrast to other reports dealing with QD grown under V-W mode, the unifo
rmity of size distribution is comparable to that obtained for QD systems gr
own under Stransky-Krastanov mode. Furthermore, the observed QD density is
consistent, at comparable surface coverages and growth temperatures. with p
reviously reported values for other QD systems. Also, as growth proceeds, a
n increase in both material incorporation efficiency and in QD aspect ratio
have been observed. Finally, the highest aspect ratio islands are found to
be faceted, indicating possible changes in QD morphology as more material
is incorporated into them. These results show that the V-W growth mode can
be successfully used to obtain self-assembled quantum dots. (C) 2001 Elsevi
er Science B.V. All rights reserved.