Wet non-thermal integration of nano binary silicon-gold system with strong plasmonic and luminescent characteristics

Abstract

We report on a wet none thermal integration of the binary silicon-gold nano system. Instead of thermally based gas-solid procedures, we use charge exchange/injection-based procedures in a chemical wet environment. SEM and TEM imaging and EDX show 0-D gold-silicon coreshell structures with diameters ranging from 6 to 500 nm in addition to a variety of silicon and gold nano structures. Optical and florescence spectroscopy show that colloids exhibit strong red luminescence and plasmonic resonance in the visible. Mie theory analysis of light scattering is in agreement with the optical observation. The results and procedures are discussed in terms of the relative electron/hole affinity, Schottky potential barrier, strength of the metal-silicon bond, as well as the surface diffusion of metal atoms or clusters on the interface of the constituent materials. Integration of gold and silicon, at the nanoscale in the form core-shell architecture affords the functionalities and attributes of plasmonic light scattering imaging and fluorescence imaging that would be useful for a wide variety of applications, including optical filters, sensing, therapeutics and tracking, and cancer therapy.