Deposition of tungsten oxide films by reactive magnetron sputtering on different substrates

Tungsten oxide films are deposited with the help of reactive magnetron sputtering in an argon/oxygen gas mixture. Films are deposited on different substrates, in particular, on soda lime glass, fluorine-doped tin oxide coated glass, silicon (Si), and quartz ( SiO2). Thin films from three different discharge modes, in particular, high power impulse magnetron sputtering, midfrequency magnetron sputtering, and radiofrequency magnetron sputtering, are compared. Deposited films are characterized by x-ray diffraction, Raman spectroscopy, and spectroscopic ellipsometry. Composition, crystal structure, and optical properties of as-deposited and annealed films are found to depend on the deposition mode and on the substrate.