Processing of SiO2-TiO2 Thin Film Waveguides

Abstract

ABSTRACTThe shrinkage behavior and changes in refractive index of sol-gel derived SiO2 -TiO2 thin films, with a composition of 50 mole %, were investigated. Two regions of shrinkage rate were observed, a rapid initial stage and a slower second stage. The refractive index of the film was found to be dependent upon the heat treatment. Samples prebaked to 100°C and processed at temperatures below 500°C were found to have lower indices than films processed without prebaking. Films heated to 700°C contained small crystallites of anatase uniformly distributed throughout the film.