Giant Enhancement of Light Emission from Au Nanocrystals into a Porous Matrix Integrated with Silicon Platform

Abstract

Integration of metal nanoparticle-dielectric films with silicon technology is emerging as a promising candidate for sub-wavelength optoelectronics and correlated devices. A giant enhancement of the luminescence intensity of gold nanocrystals directly prepared on a nanoporous template of anodized aluminium oxide is evaluated herewith, for the first time in literature, as a favourable substrate for integrating silicon-based optoelectronics. The size and lateral separation between adjacent particles are controlled by the geometry of the dielectric matrix and on-chip-integration is achieved during the nanoparticle growth, requiring no further steps. A more pronounced photoresponse is observed with embedded nanocrystals as small as 12 nm and the high emission is attributed to the light confinement associated to the increase of the local field effect on the surface plasmon hybridization waves. The demonstrated ability to control the assemble of the nanocrystals and the intense light emission indicate that the embedded gold nanostructures have a high potential for plasmonic device applications.