The Bragg grating forms an essential element in optical telecommunication and sensing applications. In the case of integrated optics, it is necessary to incorporate the grating into a waveguide during device fabrication. Specifically for silicon photonics this process is deemed necessary to be compatible with standard processing technology. We have recently developed a method for the fabrication of Bragg gratings via self‐ion implantation of silicon‐on‐insulator (SOI) waveguides, such that the surface of the waveguide remains planar. This has significant benefits for a number of devices especially those requiring subsequent wafer bonding. Here we report work that shows the ability of these devices to be thermally tuned. As the waveguides are heated, a positive shift in the resonant wavelength is induced due to the temperature dependence of the index of refraction and thermal expansion of the silicon. The observed shift is 0.080 nm/degree, in good agreement with theoretical prediction. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The refractive index modulation associated with the implantation of oxygen or silicon into waveguides formed in silicon-oninsulator (SOI) has been investigated to determine the feasibility of producing planar, implantation induced Bragg grating optical filters. A two-dimensional coupled mode theory-based simulation suggests that relatively short grating lengths, on the order of a thousand microns, can exhibit sufficient wavelength suppression, of > 10 dB, using the implantation technique. Fabricated planar implanted slab-guided SOI waveguides demonstrated an extinction of −10 dB for TE modes and −6 dB for TM modes for the case of oxygen implantation. Extinctions of −5 dB and −2 dB have been demonstrated with silicon implantation.

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