Hyper-doping of silicon for plasmonics in the telecommunication range

We investigate hyper-doping, a promising approach to introduce a high concentration of impurities into silicon beyond its solid solubility limit, for its potential applications in near-infrared plasmonics. We systematically explore the incorporation of dopants into silicon using ion implantation and subsequent pulsed laser melting / annealing processes. Reflectance spectra analysis shows an achievable plasma wavelength of around 1.5 μm for dopant concentrations exceeding 4 at.%. Complex refractive index data for the doped silicon samples are extracted, revealing their potential for near-infrared plasmonic applications. The findings of this study offer significant insights into the utilization of hyper-doped silicon for advanced photonic and optoelectronic devices. • Achieved silicon hyper-doping with over 4 at.% active dopants via pulsed laser melting. • Transmission electron microscopy confirmed defect-free epitaxial regrowth at optimal laser settings. • Obtained plasma wavelengths down to approximately 1.5 μm for near-infrared plasmonics. • Extracted complex refractive index shows strong Drude-like optical behavior in highly doped silicon.