Periodic chains of gold nanoparticles and the role of oxygen during the growth of silicon nanowires

The introduction of oxygen during silicon monoxide-vapor liquid solid growth of silicon nanowires causes a shift in silicon suboxide stoichiometry resulting in an increased formation of silicon dioxide at the nanowire surface. This leads to instabilities of the usual cylindrical nanowire core-shell structure, where the liquid gold/silicon alloy droplet at the nanowire tip is incorporated inside a silicon dioxide nanowire to form a periodic array of nanoparticles. The structure and the composition of the resulting nanostructure are investigated using transmission electron microscopy. The influence of the oxygen is investigated experimentally and supports the authors' model of the formation mechanism. (c) 2006 American Institute of Physics.