Abstract
Porous MgF2 is a highly promising film material for the preparation of durable antireflective coatings. Synthesis routes based on Mg(OMe)2 and Mg(OAc)2 precursors are described, and the resulting sol–gel films and their thermal consolidation are compared using thermal analysis (TGA/DTA), scanning electron microscopy, ellipsometric porosimetry and X-ray diffraction. Due to their constant viscosity, Mg(OAc)2-based coating solutions are superior from the practical point of view. The porous films are stable against degradation under the steady-state temperature humidity life test (85/85), and they can successfully be integrated into TiO2–MgF2–TiO2 interference filters.
Graphical Abstract
Porous MgF2 antireflective λ/4 coatings were prepared by sol–gel processing. Synthesis routes based on Mg(OMe)2 and Mg(OAc)2 precursors are established, and the properties of the resulting film materials are compared, respectively.
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This project was funded by the German Federal Ministry of Economics and Technology (Grant 0329800).
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Scheurell, K., Kemnitz, E., Garcia-Juan, P. et al. Porous MgF2 antireflective λ/4 films prepared by sol–gel processing: comparison of synthesis approaches. J Sol-Gel Sci Technol 76, 82–89 (2015). https://doi.org/10.1007/s10971-015-3754-9
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DOI: https://doi.org/10.1007/s10971-015-3754-9