METHOD FOR ADJUSTING CHARACTERISTIC OF OPTICAL CIRCUIT

摘要

PURPOSE:To provide the method for adjusting characteristics of an optical circuit capable of efficiently controlling the local refractive index or optical path length of optical waveguides constituting the optical circuit. CONSTITUTION:A Mach-Zehnder interferometer composed of directional couplers 12a, 12b and optical waveguides 13a, 13b formed on a silicon substrate 11 is impregnated with hydrogen at room temp. and is subjected to a heat treatment, by which the sensibility with a light induced change in refractive index is easily and safely improved with good controllability. Only a part of the optical waveguide 13a not coated with a metallic film 22 is thereafter irradiated with UV light from a KrF excimer laser 23, by which the refractive index thereof is corrected and the characteristics are adjusted.