Effect of post-treatment on ordered mesoporous silica antireflective coating

Abstract

Ordered mesoporous silica coating used as an optical antireflective (AR) coating was successfully prepared using tetraethyl orthosilicate as a precursor in the direction of surfactant F127. After various post-treatments, the effect of optical, surface and structural properties on ordered mesoporous silica AR coating was investigated. Ammonia vapor treated ordered mesoporous AR coating showed high transmittance of 99.99% on a quartz substrate. After hexamethyldisilazane (HMDS) treatment, the contact angle with water increased from 7° to 88°. The in situ grazing incident small angle X-ray scattering (GISAXS) was used to investigated the structure evolution of the ordered mesoporous silica coating during the calcination process. The results indicated that the mesopores in the coating constructed a Fmmm orthorhombic symmetry structure with (010) planes parallel to the substrate. The silica network contracted along the direction vertical to the substrate during calcination to remove the template, while in the direction parallel to the substrate, the shrinkage was hindered by the adhesion of the coating. In addition, the Fmmm orthorhombic symmetry structure was maintained after various post-treatments.