Patent ID: 6996321

Claim:
A method of manufacturing an optical waveguide, wherein the optical waveguide comprises an undercladding layer, a waveguide layer formed on the undercladding layer and having a higher refractive index than that of the undercladding layer, and an overcladding layer covering the waveguide layer and having a lower refractive index than that of the waveguide layer, the method comprising steps of: using the undercladding layer as a substrate and forming on the substrate a crystal growth nucleation position, wherein the crystal growth nucleation position comprises a groove or hole formed in the substrate or a groove or hole formed in an electrode layer provided on the substrate; and growing a thin film of an optical functional material KTa x Nb 1-x O 3 (0<x<1) into a rectangular parallelepiped with the structure as a center to form the waveguide layer.