Optical waveguide device and manufacturing method of optical waveguide device

Abstract

A manufacturing method of an optical waveguide device that allows light to propagate through a core formed within a cladding formed on a substrate, the core having a higher refractive index than the cladding, includes: layering a first cladding-material layer for the cladding and a core-material layer for the core sequentially on the substrate; forming the layered core-material layer into the core having a waveguide shape, and removing a first part of the core, the first part being positioned at a portion where a slit is to be formed, to thereby form a gap in the core; layering a second cladding-material layer for the cladding to cover the first cladding-material layer and the core; and removing, by dry-etching, a second part of the first and second cladding-material layers, the second part being positioned at the portion where the slit is to be formed, to thereby form the slit.