Optical study of Ag-TiO₂ nanocermet thin films prepared by R.F. co-sputtering

¹ Laboratoire de Physique des Matériaux, Université Mohammed V, Faculté des Sciences, avenue Ibn Batouta, B.P. 1014 Rabat, Morocco
² Laboratoire d'Optique des Solides (UMR 7601) , Université Pierre et Marie Curie, Case 80, 4 place Jussieu, 75252 Paris Cedex 05, France
³ Physics Department, University of the Witwatersrand, Wits 2050, Johannesburg, South Africa

Corresponding author: lafait@ccr.jussieu.fr

Received: 8 March 1999
Revised: 17 May 1999
Accepted: 6 December 1999
Published online: 15 February 2000

Abstract

The optical properties of Ag-TiO₂ nanocermet thin films are studied with the aim of optical filtering applications. Beyond the classical properties of cermets with noble metal inclusions predicted by the effective medium theories, the optical properties of Ag-TiO₂ nanocermets deposited by R.F. co-sputtering are governed by their columnar morphology and the under-stoichiometry of the TiO₂ matrix. A careful experimental analysis of the different parameters and effects involved in the optical response of these nanocermets is performed both on TiO₂ and Ag-TiO₂: film thickness, silver volume fraction, thermal treatments, oxidation. The influence of these parameters on the surface plasmon resonance and the infrared transmission of the nanocermet thin films is optimized.