Optical behavior of RF sputtered Au-TiO₂ thin cermet films, influence of the gold particles size and concentration

¹ Laboratoire de Magnétisme et d'Optique de Versailles (UMR CNRS 8634), Université de Versailles Saint Quentin, 45 avenue des États-Unis, 78035 Versailles Cedex, France
² Institut de Réactivité, Électrochimie et Microporosité (UMR CNRS C0173), Université de Versailles Saint Quentin, 45 avenue des États-Unis, 78035 Versailles Cedex, France
³ Laboratoire des Milieux Désordonnés et Hétérogènes (UMR CNRS 7603), Université Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France

Corresponding author: quelin@physique.uvsq.fr

Received: 29 December 1998
Revised: 5 July 1999
Accepted: 6 June 2000
Published online: 15 August 2000

Abstract

We study the optical behavior of Au-TiO₂ thin cermet films, the gold volume fraction of which is varied over the range 10⁻³ to 8 × 10⁻². In this low concentration range, it is mainly governed by the metallic particles size, which very much depends on the deposition substrate temperature and the annealing time and temperature. The samples structure and morphology are characterized by several complementary techniques. Spectrophotometric measurements at quasi-normal incidence have been performed in visible and near infrared regions. Using a short pulse Nd:YAG laser, we also look for nonlinear optical behavior due to the enhancement of the electromagnetic field close to the surface plasmon resonance of the metallic grains.