@Article{TestoniCPFMSGVM:2016:InAlPa,
author = "Testoni, G. E. and Chiappim, W. and Pessoa, R. S. and Fraga,
Mariana Amorim and Miyakawa, W. and Sakane, K. K. and Galv{\~a}o,
N. K. A. M. and Vieira, L. and Maciel, H. S.",
affiliation = "{Universidade do Vale do Para{\'{\i}}ba (UNIVAP)} and
{Universidade do Vale do Para{\'{\i}}ba (UNIVAP)} and
{Universidade do Vale do Para{\'{\i}}ba (UNIVAP)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto de Estudos
Avan{\c{c}}ados (IEAv)} and {Universidade do Vale do
Para{\'{\i}}ba (UNIVAP)} and {Instituto Tecnol{\'o}gico de
Aeron{\'a}utica (ITA)} and {Universidade do Vale do
Para{\'{\i}}ba (UNIVAP)} and {Universidade do Vale do
Para{\'{\i}}ba (UNIVAP)}",
title = "Influence of the Al2O3 partial-monolayer number on the
crystallization mechanism of TiO2 in ALD TiO2/Al2O3 nanolaminates
and its impact on the material properties",
journal = "Journal of Physics D: Applied Physics",
year = "2016",
volume = "49",
number = "37",
pages = "375301",
month = "Sept",
keywords = "nanolaminate, titanium dioxide, aluminum oxide, atomic layer
deposition.",
abstract = "TiO2/Al2O3 nanolaminates are being investigated to obtain unique
materials with chemical, physical, optical, electrical and
mechanical properties for a broad range of applications that
include electronic and energy storage devices. Here, we discuss
the properties of TiO2/Al2O3 nanolaminate structures constructed
on silicon (1 0 0) and glass substrates using atomic layer
deposition (ALD) by alternatively depositing a TiO2 sublayer and
Al2O3 partial-monolayer using TTIP-H2O and TMA-H2O precursors,
respectively. The Al2O3 is formed by a single TMA-H2O cycle, so it
is a partial-monolayer because of steric hindrance of the
precursors, while the TiO2 sublayer is formed by several TTIP-H2O
cycles. Overall, each nanolaminate incorporates a certain number
of Al2O3 partial-monolayers with this number varying from 10-90 in
the TiO2/Al2O3 nanolaminate grown during 2700 total reaction
cycles of TiO2 at a temperature of 250 degrees C. The fundamental
properties of the TiO2/Al2O3 nanolaminates, namely film thickness,
chemical composition, microstructure and morphology were examined
in order to better understand the influence of the number of Al2O3
partial-monolayers on the crystallization mechanism of TiO2. In
addition, some optical, electrical and mechanical properties were
determined and correlated with fundamental characteristics. The
results show clearly the effect of Al2O3 partial-monolayers as an
internal barrier, which promotes structural inhomogeneity in the
film and influences the fundamental properties of the
nanolaminate. These properties are correlated with gas phase
analysis that evidenced the poisoning effect of trimethylaluminum
(TMA) pulse during the TiO2 layer growth, perturbing the growth
per cycle and consequently the overall film thickness. It was
shown that the changes in the fundamental properties of TiO2/Al2O3
nanolaminates had little influence on optical properties such as
band gap and transmittance. However, in contrast, electrical
properties as resistivity and mechanical properties as hardness
and elastic modulus were shown to be very dependent. From these
analyses, several applications could be suggested for different
kinds of nanolaminates obtained in this work.",
doi = "10.1088/0022-3727/49/37/375301",
url = "http://dx.doi.org/10.1088/0022-3727/49/37/375301",
issn = "0022-3727",
language = "en",
targetfile = "testoni_influence.pdf",
urlaccessdate = "27 abr. 2024"
}