Local synthesis of tungsten oxide nanowires by current heating of designed micropatterned wires

We locally synthesized tungsten oxide nanowires at predetermined positions by current heating of designed micropatterned wires. The current wires were fabricated from tungsten thin film and had two different widths in the same wire, and the narrower sections were heated more than the wider sections due to the difference in electric resistance. The temperature of the narrower sections was controlled to be optimal for nanowire synthesis in an O-2 atmosphere in a vacuum chamber. We demonstrated the synthesis of nanowires over an area of approximately 1 x 1 mu m(2) and successfully synthesized nanowires on a regular 20 by 20 array with narrow sections with 10 mu m pitch. (C) 2008 The Japan Society of Applied Physics.