ORGANIC-INORGANIC HYBRID SOL-GEL MATERIALS FOR OPTICAL WAVEGUIDE APPLICATION

Ridge optical waveguides based on organic-inorganic (hybrid) sol-gel materials were designed, simulated and fabricated. The hybrid sol-gel materials were synthesized from vinyltriethoxysilane (VTES), tetraethoxysilane (TEOS) and tetrabutoxytitanate (TTBu) precursors by means of sol-gel processing technique. The optical waveguides were fabricated on quartz substrate using spin coating, direct photolithography, and wet chemical etching techniques. Multiple layers of sol were deposited so as to obtain waveguide structure with suitable thickness for mode propagation such as acquired from the simulation. Waveguiding ability of the ridge optical waveguides at 1550 nm wavelength was characterized using direct end-face fiber butt-coupling method. Physical structure of the waveguides was observed through high power microscope. Observation showed that the proposed material possesses the ability for waveguiding application at the wavelength of 1550 nm. Simulation showed that a single mode ridge optical waveguide could be realized provided that the structure thickness and width are within certain range. The range is attainable through proper control of spin coating and micropatterning parameters. Acceptable end-face quality resulted from natural cleaving process was also discovered.