Tailoring plasmonic resonances in Cu-Ag metal islands films
Bubaš, Matej (Ruder Bošković Institute)
Janicki, Vesna (Ruder Bošković Institute)
Mezzasalma, Stefano A. (Lund Institute of Advanced Neutron and X-ray Science)
Spadaro, Maria Chiara (Institut Català de Nanociència i Nanotecnologia)
Arbiol i Cobos, Jordi (Institut Català de Nanociència i Nanotecnologia)
Sancho-Parramon, Jordi (Ruder Bošković Institute)

Date:	2021
Abstract:	The plasmonic response of Cu-Ag metal islands films is investigated. Films are obtained by subsequent electron beam deposition of Ag and Cu using different fabrication conditions: deposited mass thickness, substrate temperature and post-deposition annealing in vacuum. Optical properties of films are investigated by spectroscopic ellipsometry and correlated with the structural characterization results obtained by electron microscopy. It is observed that Ag enhances island growth and increases the percolation threshold of Cu films. The localized surface plasmon resonance of isolated particles shows signatures of both Cu and Ag. Moderate thermal annealing enhances island growth and favours Janus-like morphology, increasing the Ag contribution to the surface plasmon resonance. In case of percolated films, annealing-induced dewetting can lead to the appearance of large and irregular particles with a remarkable absorption peak in the near-infrared range. Composition and optical properties of the films can be further modified by Ag partial evaporation upon annealing at high temperatures. The variation of optical properties with aging is related to Cu oxidization and follows different trends depending on the sample morphology. Overall, it is shown that Cu-Ag island films are compelling systems for plasmonic applications, as their optical response can be widely and easily tuned by adjusting fabrication conditions.
Grants:	European Commission 754510 Ministerio de Economía y Competitividad SEV-2017-0706 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-327
Note:	Altres ajuts: ICN2 is funded by the CERCA Programme/ Generalitat de Catalunya.
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades.
Language:	Anglès
Document:	Article ; recerca ; Versió sotmesa a revisió
Subject:	Surface plasmon resonance ; Metal islands films ; Ellipsometry ; Optical properties ; Dewetting ; Electron microscopy ; Janus nanoparticles
Published in:	Applied surface science, Vol. 564 (Oct. 2021) , art. 150260, ISSN 0169-4332

DOI: 10.1016/j.apsusc.2021.150260

Preprint 31 p, 2.2 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles