Thermo-optic waveguide device and manufacturing method thereof

Abstract

A thermo-optic waveguide device of a low cost, with low power consumption and low thermal stress, and having excellent mass-productivity, and a manufacturing method thereof are provided. The thermo-optic waveguide device includes, on a substrate, an optical waveguide and a thin-film heater that exerts a thermo-optic effect on the optical waveguide. The thermo-optic waveguide device further includes a thermal separation groove arranged substantially in parallel with an optical waveguide core along at least one side of the optical waveguide core corresponding to the thin-film heater. In the manufacturing method of the thermo-optic waveguide device, the thermal separation groove arranged near the optical waveguide core is formed together with the optical waveguide, in a process of forming the optical waveguide on the substrate by using a photopolymer.

Description

technical field [0001] The present invention relates to a thermo-optical effect type optical waveguide element including an optical waveguide on a substrate and a thin-film heater for causing the optical waveguide to generate a thermo-optical effect, and a method for manufacturing the thermo-optical effect type optical waveguide element. Background technique [0002] Optical waveguide elements utilizing thermo-optical effects are widely used in optical elements such as optical switches, variable optical attenuators (VOA: Variable Optical Attenuation), and optical sensors used in general optical communication systems or optical propagation systems. The so-called thermo-optical effect refers to the phenomenon that the refractive index of the optical waveguide material changes due to heating. [0003] A thermo-optical effect type optical switch uses an optical waveguide formed of a material having a thermo-optical effect, and switches an output port of light by changing the ref...

AI Technical Summary

Problems solved by technology

[0011] That is, when the thermal isolation groove is formed by cutting after forming the optical waveguide, it is difficult to form a groove with a certain depth.

In addition, for high-density formation of complex patterned waveguides, the formation of grooves itself is difficult, and arbitrary shapes other than straight lines cannot be formed.

[0012] For example, in the case of the optical switch described in Japanese Patent Application Laid-Open No. 2004-85744, the waveguide cores of a few microns to the thermal isolation grooves at intervals of tens of microns are formed on a highly densely integrated waveguide wafer. The cutting process of the knife has problems in the shape accuracy of the groove, position accuracy and mass production.

[0013] In addition, when thermal isolation grooves are formed by dry etching after formation of the optical waveguide, the problem of high cost of processing equipment cannot be avoided.

[0014] For example, in the case of the optical waveguide described in JP-A-2004-309927, in order to perform dry etching after forming the optical waveguide, an expensive processing device is required, and there is a problem that the processing cost of the optical element increases.

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