| 摘要 |
PROBLEM TO BE SOLVED: To obtain an etching layer with which smooth ridge side walls may be embodied and the manufacture of optical waveguides of low propagation loss is possible by laminating a thin-film layer consisting of a metallic material via an intermediate thin-film layer consisting of an oxide material on a thin-film layer consisting of a metallic material. SOLUTION: After a Ti thin-film layer 9a comprising the metallic material, which is an etching mask layer, is formed on an LiNbO3 substrate 1, the SiO2 thin-film layer (intermediate thin-film layer) 16 comprising the oxide material is thinly formed thereon. Further, the Ti thin-film layer 9b is laminated again thereon and the laminated Ti thin-film layer 9b is etched by using resist patterns 10. The growth of the microcrystals formed in the Ti thin-film layer 9b is suppressed by the SiO2 film which is the intermediate thin-film layer and, therefore, the side etching of the Ti patterns is thereby suppressed and consequently, the optical waveguides of the low propagation loss of the ridge structure having the smooth side walls is manufactured. |
