Voids and nanopores in nanocolumnar platinum thin films grown by magnetron sputtering and evaporation at oblique angles: A comparative analysis

Nanocolumnar thin films deposited at oblique angle (OA) by magnetron sputtering or evaporation often show common structural aspects when grown under equivalent geometrical conditions. This is the case of the column tilt angle as a function of the geometrical deposition arrangement, which coincides f...

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Bibliographic Details
Authors: García Valenzuela, Augusto, Acosta Rivera, Hiedra, Oskar Liedke, Maciej, Butterling, Maik, Hirschmann, Eric, Attallah, Ahmed G., Wagner, Andreas, Rojas, T. C., Álvarez Molina, Rafael, Rico-Gavira, Víctor Joaquín, Palmero, Alberto, Rodríguez González-Elipe, Agustín
Format: article
Status:Published version
Publication Date:2025
Country:España
Institution:Universidad de Sevilla (US)
Repository:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:dnet:idus________::5bd642d18527a6f1e003b58897d9b209
Online Access:https://hdl.handle.net/11441/186939
https://doi.org/10.1016/j.surfin.2025.106667
Access Level:Open access
Keyword:Positron annihilation spectroscopy
Nanocolumnar thin films
Oblique angle deposition
Magnetron sputtering
Evaporation
Porous thin films
Description
Summary:Nanocolumnar thin films deposited at oblique angle (OA) by magnetron sputtering or evaporation often show common structural aspects when grown under equivalent geometrical conditions. This is the case of the column tilt angle as a function of the geometrical deposition arrangement, which coincides for some materials no matter the technique. This feature has usually been taken as a sign of a common type of growth, even though no other morphological aspects have been systematically compared. In this paper, a comparison between nanocolumnar Pt thin films grown at OA by evaporation and magnetron sputtering has been carried out, demonstrating the existence of profound differences in film density, columnar width or preferential crystalline texture, despite exhibiting the same nanocolumnar tilt. Moreover, the size distribution of voids and nanopores embedded in the nanocolumns has been specifically analyzed by means of two Positron Annihilation Spectroscopy techniques, demonstrating the existence of large variations depending on the preparation method. With the help of a growth model, these differences are discussed under the light of the atomistic processes present in evaporation and magnetron sputtering and, more specifically, on mobility processes triggered by the arrival of deposition atoms with relatively high kinetic energy.