METHOD FOR MANUFACTURING FLAT-TYPE SILICA THIN FILM USING WIDE FLAME HYDROLYSIS DEPOSITION METHOD IN HIGH TEMPERATURE ATMOSPHERE

摘要

PURPOSE: A method for manufacturing a flat-type silica thin film using a wide flame hydrolysis deposition method in a high temperature atmosphere is provided to achieve uniformness of composition in both vertical and horizontal directions, reduce a processing time, decrease a manufacturing cost and precisely control the composition. CONSTITUTION: A wide flame hydrolysis deposition method is used to make an under-clad layer and a core layer of a silica optical waveguide on a silicon substrate. A silica glass thin film is deposited. Germanium, boron and phosphorous are added for a core layer silica particle deposition so that a refractive index of the core silica film can be higher than that of the under-clad layer and an upper-clad silica film, thereby guiding a light along the core layer. A dry-etch mask layer like a Cr thin film is deposited on the core layer after the under-clad and the core layer are formed. A photo-resist is coated. A photo-lithography and a wet-etch method are performed for transfer by using a two dimensional flat shape to the optical waveguide as a photo-mask. The dry-etch method is used to etch the core silica layer into a channel optical waveguide of quadrangular shape. The wide flame hydrolysis deposition method is used again to deposit the upper-clad silica particle layer and thus complete a silica optical waveguide.