Nanophotonic Devices Based on Silicon-On-Insulator Nanowire Waveguides

While silica-on-silicon is recognized as one of the dominant platforms for microphotonics today, silicon-on-insulator nanowire waveguides appear to be the technology for next generation of super compact integrated devices. Due to very high refractive index contrast and strong light confinement in the core, the waveguide bend radius can be reduced to a few micrometers and the size reduction of the functional integrated circuits can reach several orders of magnitude. An array waveguide grating multi/demultiplexer that usually occupies several square centimetres in silica-on-silicon technology can be reduced to the size of 50 times 50 mum². The performance of such miniaturized devices with submicrometer-size waveguides strongly depends on the fabrication accuracy: high resolution patterning and low roughness etching. High quality and high precision optimized processing is necessary to obtain satisfactory results. We discuss here the technology issues as well as present some fabricated devices based on silicon nanowire waveguides