Si-Fe composites with embedded α-FeSi2 nanocrystals: formation and thermoelectric properties

The technology of embedding metallic iron disilicide (α-FeSi₂) nanocrystals (NCs) with different numbers of NCs multilayers and different doping levels of silicon multilayers with holes (10¹⁹ cm^-3 and 10¹³ cm^-3) was tested on SOI substrates, and composites with 4 and 8 layers of embedded α-FeSi₂ NCs were grown using it. The maximum power factor 0.1 to 0.25 mW/ (mxK²) at T = 450 K was observed in the composite with the maximum hole concentration in the silicon interlayers, and a decrease in the hole concentration led to a decrease in the power factor to 0.01 mW/ (mxK²) at T = 450 K due to a sharp decrease in the sheet resistance with a weak increase in the Seebeck coefficient.