J. Gil-Rostra, J. Chaboy, F. Yubero, A. Vilajoana, A.R. González-Elipe
ACS Applied Materials and Interfaces, 5 (2013) 1967-1976
doi: 10.1021/am302778h

This work describes the reactive magnetron sputtering processing at room temperature of several mixed oxide M_xSi_yO_z thin films (M: Fe, Ni, Co, Mo, W, Cu) intended for optical, coloring, and aesthetic applications. Specific colors can be selected by adjusting the plasma gas composition and the Si–M ratio in the magnetron target. The microstructure and chemistry of the films are characterized by a large variety of techniques including X-ray photoemission spectroscopy, X-ray absorption spectroscopy (XAS), and infrared spectroscopy, while their optical properties are characterized by UV–vis transmission and reflection analysis. Particularly, XAS analysis of the M cations in the amorphous thin films has provided valuable information about their chemical state and local structure. It is concluded that the M cations are randomly distributed within the SiO₂matrix and that both the M concentration and its chemical state are the key parameters to control the final color of the films.