Plasmon-Enhanced Emission From CMOS Compatible Si-LEDs With Gold Nanoparticles

Complementary metal-oxide-semiconductor (CMOS) compatible silicon (Si)-based light sources are attracting more and more attention for the potential to realizing on-chip optical interconnection ultimately. Annealed noble metal nanoparticles (NPs) are often used to enhance the emission efficiency of low-efficiency light emitters due to the surface plasmon (SP) effects. Compared with silver NPs (Ag NPs) and gold NPs (Au NPs) show excellent stability in the air environment. However, Au NPs are not always chosen to enhance the emission efficiency of light-emitting diodes (LEDs) due to the high annealing temperature and CMOS incompatible. Here, we report the first study of enhancing emission from CMOS compatible Si-based LEDs by transferring annealed Au NPs onto the device surfaces. A 4.3-fold total enhancement integrated across the electroluminescence spectrum and an eightfold enhancement at 900 nm are ultimately achieved. The enhancement is attributed to electrical performances improvement of the Si-based LEDs and enhanced scattering by Au NPs due to the coupling between the SP modes of Au NPs and the waveguide modes of Si slab waveguide.