Control of Si nanowire growth by oxygen.

摘要: Semiconductor nanowires formed using the vapor-liquid-solid mechanism are routinely grown in many laboratories, but a comprehensive understanding of key factors affecting wire growth is still lacking. In this paper we show that, under conditions low disilane pressure and higher temperature, long, untapered Si wires cannot be grown, Au catalyst, without presence oxygen. Exposure to oxygen, even at levels, reduces diffusion away from catalyst droplets. This allows droplet volumes remain constant for longer times therefore permits wires. effect observed both gas-phase surface-bound so source oxygen unimportant. The control exposure during provides new tool fabrication uniform-diameter structures, as required applications nanowires.