OPTICAL DEVICE HAVING OPTICAL WAVEGUIDE

摘要

PURPOSE:To form an optical waveguide having a flat end face without roundness on a substrate by forming the optical waveguide on the substrate surface and forming further a buffer layer on the optical waveguide. CONSTITUTION:The buffer layer 3 is formed on the substrate 2 and the optical waveguide 4 of optical waveguide layer of a prescribed pattern or an optical waveguide is formed thereon. The buffer layer 6 is further formed on such waveguide 4. The waveguide 4 is formed by sputtering glass and the buffer layers 3, 6 are formed by sputtering SiO2. The thickness (f) of the buffer layer 6 is made larger than the thickness (d) in the part 6a to be eroded by a polishing agent in the stage of polishing the end face. Then the part to be removed by the polishing agent in the end face grinding of the substrate 2 is only the edge of the buffer layer 6 and since the erosion by the polishing agent does not arrive at the end face of the waveguide 4, the end face of the waveguide 4 is flatly polished.