| 摘要 |
The present invention relates to an optical waveguide circuit such as an arrayed waveguide grating, etc. A lower cladding is formed on a silicon substrate. A core having the following waveguide construction is formed thereon. That is, an input side slab waveguide is connected to the emission side of a plurality of incidence waveguides, a plurality of arrayed waveguides having different lengths form each other are juxtaposed at and connected to the emission side thereof, an output side slab waveguide is further connected to the emission side thereof, and a plurality of emission waveguides are connected to the emission side thereof, thereby causing the abovementioned waveguide construction. The upper cladding covers up the core. The cladding and core are made of silica-based glass, wherein the value B of birefringence occurring in said optical waveguide portion is |B|<=5.34x10-5, and alphas-2.0x10-7<=alphag <=alphas+2.0x10-7 is established where it is assumed that the thermal expansion coefficient of the upper cladding is alphag, and the thermal expansion coefficient of a silicon substrate is alphas.
|
