Nanosilicon for photonic applications

This presentation is a short review of some scientific insights on the possibilities of photonic applications of nanostructured silicon (NS-Si), porous Si (p-Si) and Si nanocrystals (NC-Si), one of the most interesting problems in nano-crystallite physics. The emission mechanism of a very bright photo-luminescence (PL) band and relatively weak electro-luminescence (EL) are presently the main issue. The basic question lies in whether the emission is an extrinsic or intrinsic property of nanocrystals. It is important from a fundamental physics viewpoint because of the potential application of Si wires and quantum dots in optoelectronic devices and information technology. Nanostructuring silicon is an effective way to turn silicon into a photonic material. It is observed that low-dimensional (one and two dimensions) silicon shows light amplification, photon confinement, photon trapping as well as non-linear optical effects. There is strong evidence of light localization and gas sensing properties of such nanostructures. Future nanotechnology would replace electrical with optical interconnects, which has appealing potential for higher-speed performance and immunity to signal cross talk.