Preparation of hydrophobic anti-reflective SiO2 films for high laser resistance by Sol-Gel Process

A sol containing SiO2 particles was prepared by the base catalyzed hydrolysis and polycondensation of tetraethoxysilane (TEOS) through sol-gel process. A solution containing double-chain polymer of methyltriethoxysilane (MTES) was also prepared under acid condition, as the introducer of water repellence. After mixing these two kinds of sols, spinning coating was used to deposit films on glass. Several techniques-photon correlation spectrum，TEM and small angle X-ray scattering, were used to characterize the microstructure. The transmission and wet-angle for water of films were measured by UV-Vis and contact angle analyzer. The reflection -can be reduced to 0.01% and the wet-angle for water was 118°at most. A Nd:YAG laser was used to determine the laser damage threshold of film at 1 064nm.