Reflecting Multi-Layer Coatings by RF Sputtering

Abstract:

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-O2 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.

• Periodical: Materials Science Forum (Volume 502)
• Pages: 309-314
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.502.309
• Online since: December 2005
• Authors: Fujio Tamai, Yuji Kawakami
• Keywords: Multilayer, Reflection, Refractive Index, RF Sputtering, SiO₂, Ta₂O₅

References

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[2] 2 Refractive index, n Deposited thin film Index of refraction at 630nm TiO2 Ta2O5.

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[2] 045 Absorption at 630 nm Ta2O5 Doped 12wt% Bi2O3 Ta2O5 Doped 7wt% Bi2O3.

000.

000.

000.

000 Fig. 2 Refractive index of the as-deposited Ta2O5 thin films over the range 350 nm to 830. Table 2 Absorption and the refractive index (a) XRD patterns of Ta2O5 films (b) XRD patterns of Ta2O5 films doped 7wt% Bi2O3 Fig. 3 Patterns of XRD for the films after 973K annealing.

DOI: 10.1016/s0040-6090(99)00019-x