| 摘要 |
PURPOSE:To perform sufficient integration by providing a waveguide pattern made of specific metal on a refractive index gradient formed in a 1st diffused area after the area is formed, diffusing the same metal thermally and forming a 2nd diffused area, and using it as a waveguide. CONSTITUTION:A 1st titanium metal pattern 4 is formed firstly on an LiNbO3 substrate 3 and diffused thermally to form the 1st diffused area 6. Then, a 2nd titanium metal pattern 5 is formed at the refractive index gradient position formed as mentioned above and diffused thermally to form the 2nd diffused area which becomes an optical waveguide 2. The 1st titanium metal pattern 4 is heat-treated and then titanium ions are diffused to form the 1st diffused area 6 and then form a refractive index profile, so that refractive index gradients 7 appear on both sides of the profile. The 2nd titanium metal pattern 5 is provided at the positions of the gradients 7 and Ti is diffused to form the 2nd diffused area 8 which becomes an optical waveguide 2. Consequently, the radius of curvature is reduced to <=5mm and the degree of integration of an optical circuit element can be improved. |
