@Article{HerediaDíMaRaIiBrMo:2014:AnStBe,
author = "Heredia, Emilio and D{\'{\i}}az, Beatriz Leonila and Malachias,
Angelo and Rappl, Paulo Henrique de Oliveira and Iikawa, Fernando
and Brasil, Maria Jos{\'e} Santos Pompeu and Motisuke, Paulo",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Laborat{\'o}rio Nacional de Luz S{\'{\i}}ncrotron} and
{Universidade Federal de Minas Gerais} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and UNICAMP and UNICAMP and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Anomalous strain behavior on EuTe self-assembled islands",
journal = "Journal of Crystal Growth",
year = "2014",
volume = "386",
pages = "139--145",
month = "Jan.",
keywords = "EuTe, magneto-optic materials, molecular beam epitaxy,
nanostructures, high resolution X-ray diffraction.",
abstract = "EuTe is a magnetic semiconductor with potential applications in
prototype optoelectronic and spintronic devices. In this work, we
investigated the structural properties of EuTe grown on BaF2(111)
substrates by molecular beam epitaxy. X-ray diffraction
measurements were performed on two series of samples with
different growth times and temperatures. The growth occurs in the
Volmer-Webber mode, with initial formation of islands that then
coalesce to form thin films. The islands size, mosaic spread, and
strain state are deduced as a function of growth conditions.
Surprisingly, the EuTe islands exhibit in-plane tensile strain,
while compressive strain is expected for structures grown over a
substrate with smaller lattice parameter. The islands tensile
strain relaxes with increasing deposition times and substrate
temperature, and it tends to zero for thick EuTe films. We propose
that the EuTe/BaF2 lattice mismatch is compensated by the
formation of interfacial misfit dislocations. The growth
conditions out of equilibrium favor the formation of a metastable
state with a high concentration of dislocations that
over-compensates the original misfit. This is in agreement with
the observed reduction of tensile strain as the substrate
temperature increases.",
doi = "10.1016/j.jcrysgro.2013.10.002",
url = "http://dx.doi.org/10.1016/j.jcrysgro.2013.10.002",
issn = "0022-0248",
language = "en",
url = "http://dx.doi.org/10.1016/j.jcrysgro.2013.10.002",
urlaccessdate = "04 maio 2024"
}