| 摘要 |
An optical waveguide having a small propagation loss and formed on an Si substrate having a large diameter has a lower cladding layer, a core and an upper cladding layer surrounding the core together with the lower cladding layer, each of the lower cladding layer, core and upper cladding layer being composed of a high-silica material. The upper cladding layer or each of the upper and lower cladding layers comprises three kind of dopants including germanium oxide (GeO2), phosphorus oxide (P2O5) and boron oxide (B2O3). Preferable amount of content of GeO2 in the upper cladding layer is more than 5 mole percent. The optical waveguide is suitable for a hybrid optical device including a functional device such as a semiconductor laser provided with metal patterns for electrodes and interconnections. The metal pattern can be formed before a thermal treatment of the upper cladding layer without causing a deficiency in the metal pattern during the thermal treatment. <IMAGE> |
