Optical Filters Utilizing Ion Implanted Bragg Gratings in SOI Waveguides

The refractive index modulation associated with the implantation of oxygen or silicon into waveguides formed in silicon‐on‐insulator (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.