Formation and thermoelectric properties of the n- And p-type silicon nanostructures with embedded GaSb nanocrystals

A silicon heterostructure with four layers of embedded gallium antimonide nanocrystals was formed on a Si(111) substrate by co-deposition of Ga and Sb using solid-phase epitaxy. Si(111)2 1-Sb surface reconstruction formed prior to the GaSb nanocrystal growth, which kept the nanocrystals from decomposition during the silicon epitaxial layer formation. P- and n-type structures were obtained using silicon of different conductivity types. In the 200-550 K temperature range they showed increases in both electrical conductivity and Seebeck coefficient compared with the bulk samples, which was explained by the peculiarities of the heterointerface band alignment and density of states at the Fermi level. The results open the way for creating multilayer structures with enhanced thermoelectric performance.