Preparation of TEOS-DDS Based Water-Repellent Anti-Reflective SiO_2 Films by Sol Gel Process:Effects of Micro-structure of Sols on Performances of Films

Basic sols containing amorphous SiO 2 particles were prepared trough sol gel process with TEOS(tetraethoxysilane)as precursor in alcohol systeml.Acidic sols containing polymer of DDS(dimethyldiethoxysilane)were also prepared by sol gel method.After mixing these two kinds of sols,spinning coating was used to deposit films on carefully cleaned substrates of glass and then heat treatment of films was executed in air at 80℃ for three days.Through our experints,films gained water repellence and anti reflectivity at the same time by introduce Si O Si linkage containing double CH 3.The particle size analysis by laser scattering and electroscope were employed to study microstructure of sols,such as, particle size in sols and gathering behavior of particles.The porosities of films were calculated using physic adsorption instrument.The contact angle between water drop and film and the transmittance of film were measured both before and after heat treatment.On the base of above research,we got the inner relation between the microstructure of sols and the performance of films.