| 摘要 |
PROBLEM TO BE SOLVED: To prevent deterioration of optical characteristics by suppressing adhesion of bubbles that are generated near the branching point of a core layer at the time of high temperature baking process of the upper clad layer of an optical waveguide. SOLUTION: In the structure of the optical waveguide 9, a lower clad layer 3 is formed on the entire upper surface of the substrate 2, with a core layer 10 having one or more branching points 13 formed on the upper surface of the lower clad layer 3 over the entire length in the longitudinal direction. In addition, the upper and the side surface of the core layer 10 are covered with a buffer layer 11, while the upper and the side surface of the buffer layer 11 are covered with the upper clad layer 12. COPYRIGHT: (C)2005,JPO&NCIPI |
