MgF2 antireflective coatings by sol-gel processing: preparation and performance 2.04

摘要

Porous MgF2 antireflective 1/4 coatings are highly promising materials for durable antireflective glazing: Due to the low refractive index of the backbone material a lower porosity is required for best optical performance compared to SiO2 films that are commercially available. Therefore, an improved mechanical strength can be expected from MgF2 coatings. In this contribution we describe the synthesis of MgF2 precursor solutions, their aging behavior and the wet-chemical preparation of thin films. The properties of the resulting λ/4 coatings are characterized by UV-Vis spectroscopy, Scanning Electron Microscopy (SEM), Ellipsometric Porosimetry (EP) and X-ray diffraction (XRD). The porous films are stable against degradation under the steady-state tempera-ture humidity life test (85/85) and Crock meter tests were performed. The results indicate a large potential of sol-gel derived porous MgF2 for commercial applications.