Athermal Silicon-on-insulator ring resonators by overlaying a polymer cladding on narrowed waveguides.

Photonics Research Group, INTEC-department, Ghent University-IMEC, Ghent, B-9000, Belgium.
Optics Express (Impact Factor: 3.53). 09/2009; 17(17):14627-33. DOI: 10.1364/OE.17.014627
Source: PubMed

ABSTRACT Athermal silicon ring resonators are experimentally demonstrated by overlaying a polymer cladding on narrowed silicon wires. The ideal width to achieve athermal condition for the TE mode of 220 nm-height SOI waveguides is found to be around 350 nm. After overlaying a polymer layer, the wavelength temperature dependence of the silicon ring resonator is reduced to less than 5 pm/degrees C, almost eleven times less than that of normal silicon waveguides. The optical loss of a 350-nm bent waveguide (with a radius of 15 microm) is extracted from the ring transmission spectrum. The scattering loss is reduced to an acceptable level of about 50 dB/cm after overlaying a polymer cladding.

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