| 摘要 |
PURPOSE:To allow the light signal of a long wavelength to be injected at a low coupling loss into the optical circuit by forming a light guide as a light transmission path so as to include fluoride glass. CONSTITUTION:A protective dielectric film 2 consisting of a silicon nitride film is provided on a GaAs substrate 1 and the light guide 3 consisting of the Y-shaped fluoride glass is formed thereon. The purpose of forming the protective dielectric film 2 consisting of the silicon nitride is to prevent the exertion of adverse influence of the GaAs substrate or the reaction thereof with the light guide by the evaporation of As, etc., in the GaAs substrate at the time of forming the fluoride glass on the GaAs substrate. The silicon nitride is preferable as the material for the protective dielectric film in order to prevent the reaction with the fluoride glass. Carbon nitride, boron nitride, etc., are also usable in place of the silicon nitride. |
