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 
             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 nov. 2020"