Temperature-insensitive polymeric optical AWG device and manufacturing method therefor

A method of manufacturing a polymeric optical AWG device, comprising:

• forming polymeric grating channel waveguides interposed between free propagation slab regions on a substrate between input and output waveguides and having difference lengths;
• selectively etching a surface of the substrate to form under the polymeric grating channel waveguides a plurality of hollow trenches allowing the polymeric grating channel waveguides to freely thermally expand from the substrate depending on a temperature variation so as to compensate for refractive indexes of the polymeric grating channel waveguides varying with the temperature variation;
• and
• adhering a shield layer shielding entrances of the hollow trenches so that the polymeric grating channel waveguides do not flow into the hollow trenches, so as to separate the polymeric grating channel waveguides from the substrate.

A method of manufacturing a polymeric optical AWG device, comprising:

• interposing polymeric grating channel waveguides between free propagation slab regions between input and output waveguides on a substrate;
• forming a polymer lower cladding layer;
• forming a polymer core on the polymer lower cladding layer;
• forming a polymer upper cladding layer covering the core;
• before forming the polymer lower cladding layer, selectively etching a surface of the substrate to form under the polymeric grating channel waveguides a plurality of hollow trenches allowing the polymeric grating channel waveguides to freely thermally expand from the substrate depending on a temperature variation so as to compensate for refractive indexes of the polymeric grating channel waveguides varying with the temperature variation;
• and
• adhering a shield layer shielding entrances of the hollow trenches so that the polymeric grating channel waveguides do not flow into the hollow trenches, so as to separate the polymeric grating channel waveguides from the substrate.