Structure, phase composition, and optical properties of silicon nanopowders

The nanopowders obtained by sputtering of silicon with a high-power electron beam in nitrogen and argon atmospheres have been investigated by transmission electron microscopy, Raman spectroscopy, photoluminescence spectroscopy, ultrasoft X-ray emission spectroscopy, and X-ray absorption near-edge structure spectroscopy. The sizes of particles and their phase composition have been determined. A mechanism is proposed, which explains the visible photoluminescence of nanopowders.