Synthesis of Mg2Si-based core-shell nanowires

In this work, we proposed the method for synthesis of nanowires with Mg₂Si/Sibased core-shell heterostructure. Silicon nanowires acting as a source of silicon for the silicification reaction were obtained by well-studied metal-stimulated chemical etching of silicon with orientation (100) doped with boron, with a resistivity of 1−10 Ωxcm. A 30 nm thick gold film
with an adhesive titanium sublayer 1.5 nm thick was used as the catalytic metal. The etched nanowires had a height of ~10 microns and a diameter of 1.5 microns. The Mg₂Si shell was
formed using the solid-phase epitaxy method under ultrahigh vacuum conditions. The thickness of the silicide shell was 400−600 nm on the side surfaces of the nanowires.