Preparation and characterizations of TiO2/organically modified silane composite materials produced by the sol-gel method

TiO2/organically modified silane (ORMOSIL) composite materials produced by the sol-gel method were studied for optical waveguide applications. High op tical quality waveguiding films on different substrates, including silicon, gallium arsenide, silica/silicon substrates, and microscope glass slides, were prepared from high titanium content (0.2 molar) y-glycidoxypropyltrime thoxysilane at low temperature. Scanning electron microscopy (SEM), atomic force microscopy (AFM), differential thermal analysis (DTA), thermal gravim etric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and X -ray photoelectron spectroscopy (XPS) have been used to investigate the opt ical and structural properties of the composite films. The TGA/DTA results showed that the organic compounds in the film would tend to decompose in th e temperature range from 200 degreesC to 500 degreesC. SEM and AFM results showed that a dense and porous-free composite material film could be obtain ed at the heat treatment temperature of 100 degreesC. It was also shown tha t ORMOSIL is integrated in the glass, providing low shrinkage and high crac king resistance. The propagation loss properties of the composite films wer e also investigated. About 1.1 dB/cm propagation loss of the planar wavegui de film was obtained at the wavelength of 633 nm.