Converting an insulating silicon nanochain to a conducting carbon nanotube by electrical breakdown

Electrical breakdowns of individual silicon nanochains, in which silicon nanoparticles are covered with and connected by oxide alternatively forming nanowires, are studied by in situ transmission electron microscopy using a microprobe system. Individual silicon nanochains can endure a current typically as large as 10(0) nA, and we found that a silicon nanochain can be converted to a nanotube by applying a current as large as 10(1) nA. In the nanotubes, some silicon particles are left. Experimental results suggest that nanotubes are heavily distorted carbon nanotubes, which are formed through the aggregation of contaminating carbon on the nanochain surface and the evaporation of the oxide core due to Joule heating.