NEW TECHNOLOGY FOR REDUCTION IN COST AND SIZE OF SILICA GUIDED-WAVE COMPONENT

A waveguide with SiOxNyHz core glass film and its fabrication method have been developed that can realise a high refractive index difference-DELTA to reduce the cost and size of the device. DELTA can be increased by approximately 7% by controlling the nitrogen concentration. This SiOxNyHz film is deposited on a quartz glass substrate with face down type of plasma CVD method. The warp of the substrate formed by SiOxNyHz core glass film is very small compared with that of conventional core glass film. The core side roughness on patterning of the core glass film in the dry-etching process is also very small. The plasma CVD method can suppress the growth of particles on deposited film. A reduction in the cost and size of the guided-wave type component can be expected by using the SiOxNyHz core glass.