METHOD FOR MANUFACTURING OPTICAL WAVEGUIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an optical waveguide, by which an optical waveguide having a beam spot size converter can be easily manufactured.SOLUTION: The method for manufacturing an optical waveguide includes: a step of forming a first mask layer on a multilayer film substrate 10 including a substrate 1 and a core layer 2; a step of processing the mask layer into an opening mask pattern having an opening width changing along a longitudinal direction; a step of etching the multilayer film substrate 10 by using the opening mask pattern so as to form an inclined structure 12 where an etching depth of the core layer 2 changes reflecting the changes in the opening width of the mask pattern; a step of newly forming a second mask layer on the multilayer film substrate 10 having the inclined structure 12; a step of processing the second mask layer into a waveguide mask pattern; and a step of etching the multilayer film substrate 10 by using the waveguide mask pattern so as to form an optical waveguide in a portion of the multilayer film substrate 10 where the inclined structure is present.SELECTED DRAWING: Figure 3