Several routes for the synthesis of nanoparticles of Si and their doping are under study as ion implantation and electron lithographic etching of doped SOI. The dopant mapping in nanostructures is performed by STEM-EDS. In addition, an all-optical technique based on the generation of LSPRs in doped SiNPs is used as a tool for measuring the concentration of active dopants. Finally, their plasmonic properties can be modelled using the Dyadic method of Green (see figure below).
2D map representation of the extinction efficiency for heavily doped cuboid Si-NS of size 100x100 x50 nm3 lying on a silica substrate. The dopant concentration varies between 1 and 3x1021 cm-3. The purple dashed line represents the evolution of the LSPR as a function of the dopant concentration.
Theory of plasmonic properties of hyper-doped silicon nanostructures, C Majorel, V Paillard, A Patoux, PR Wiecha, A Cuche, A Arbouet, C. Bonafos and C. Girard, Optics Communications 453, 124336.
Funding : this work is funded by the ANR DONNA ("Doping at the Nanoscale", 2018-2020, CEMES coord.) and by a Franco-Italian bilateral project (PICS 08284, 2019-2021,CEMES coord).
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