Materials Science Forum, Vol.502, 309-314, 2005
Reflecting multi-layer coatings by RF sputtering
This work is concerned with the proposition of high contrast multi-layer structure for the fabrication of reflecting surface in the visible range. The multi-layer SiO2/Ta2O5 system has superior heat resistance and reflecting properties. Ta2O5 and SiO2 thin films were prepared by RF plasma sputtering in Ar-O-2 mixed gas using Ta2O5 and SiO2 target respectively. Secondary ion mass spectroscopy and SEM observation were performed in order to investigate the multi-layer structure. The XRD and XPS analyses were also performed in order to investigate the crystal structure and the chemical state of the films. The optical constants of Ta2O5 single film were investigated by the ellipsometric analysis. Using the Ta2O5 film doped Bi2O3 for a reflecting multi-layer structure improved the reflecting properties and the heat resistance of the multi-layer system because of the high refractive index of the doped film.