We report on the growth of nanowires and unusual hollow microducts of tungsten by thermal treatment of tungsten films in a RF H2/Ar plasma at temperatures between 550-620 C. Nanowires with diameters of 10-30 nm and lengths between 50-300 nm were formed directly from the tungsten film, while under certain specific operating conditions hollow microducts having edge lengths ~ 0.5 m and lengths between 10-200 m were observed. Presence of a reducing gas like H2 was crucial in growing these nanostructures. Preferential restructuring of the film surface into nanowires or microducts appears to be significantly influenced by the rate of mass-transfer of H2 to the surface. We also give an example of the gas sensing capabilities of tungsten nanowires.
Citation: Journal of Materials Research
Issue: No. 11
Pub Type: Journals
hollow square microducts, nanowires, tungsten