Self-affine fractal vapour-deposited gold surfaces characterization by scanning tunnelling microscopy

The morphological evolution of the surfaces of gold deposits grown from the vapour on smooth glass under nonequilibrium conditions and incident angle near substrate normal is studied at the nanometer level by scanning tunnelling microscopy. For an average film thickness equal to or greater than 500...

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Detalhes bibliográficos
Autores: Salvarezza, Roberto Carlos, Vázquez, L., Herrasti, P., Ocón, P., Vara, J. M., Arvia, Alejandro Jorge
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:1992
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositório:SEDICI (UNLP)
Idioma:inglês
OAI Identifier:oai:sedici.unlp.edu.ar:10915/80010
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/80010
Access Level:Acceso aberto
Palavra-chave:Ciencias Exactas
Química
Fractales
scanning tunneling microscopy
Oro
Vapor de agua
self-affine fractals
Nanopartículas
Descrição
Resumo:The morphological evolution of the surfaces of gold deposits grown from the vapour on smooth glass under nonequilibrium conditions and incident angle near substrate normal is studied at the nanometer level by scanning tunnelling microscopy. For an average film thickness equal to or greater than 500 nm, the interface thickness (ξ) reaches a steady state. Under these conditions, ξ depends on the scan length (L) as ξ ∝ L<sup>α</sup> with α = 0.35 ± 0.05 for L > d<sub>s</sub>, where d<sub>s</sub> is the columnar size, and α = 0.89 ± 0.05 for L < d<sub>s</sub>. These results indicate that the growing surface spontaneously reaches a steady state and it can be described as a self-affine fractal. The value of α for L > ds agrees with the prediction of ballistic deposition models without restructuring, whereas that for L < d<sub>s</sub> exceeds the prediction of ballistic models including restructuring.