Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Selective formation of tungsten nanowires | Bien et al. Nanoscale Research Letters 2011 6 543 http content 6 1 543 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Selective formation of tungsten nanowires Daniel CS Bien Rahimah Mohd Saman Siti Aishah Mohamad Badaruddin and Hing Wah Lee Abstract We report on a process for fabricating self-aligned tungsten W nanowires with polycrystalline silicon core. Tungsten nanowires as thin as 10 nm were formed by utilizing polysilicon sidewall transfer technology followed by selective deposition of tungsten by chemical vapor deposition CVD using WF6 as the precursor. With selective CVD the process is self-limiting whereby the tungsten formation is confined to the polysilicon regions hence the nanowires are formed without the need for lithography or for additional processing. The fabricated tungsten nanowires were observed to be perfectly aligned showing 100 selectivity to polysilicon and can be made to be electrically isolated from one another. The electrical conductivity of the nanowires was characterized to determine the effect of its physical dimensions. The conductivity for the tungsten nanowires were found to be 40 higher when compared to doped polysilicon nanowires of similar dimensions. Keywords tungsten nanowires nanostructures self-aligned chemical vapor deposition selective deposition Background One-dimensional nanostructured materials such as nanowires nanorods and nanotubes have been the focus of intensive research owing to their unique applications in mesoscopic physics and novel nanoscale devices. These nanostructures provide a good platform to investigate the electrical thermal transport and mechanical property dependence on dimensionality and size reduction. Tungsten is a brittle refractory metal that crystallizes in body-centered cubic form. It has high tensile strength and good creep resistance. Due to its high stability tungsten or tungsten oxide nanowires are promising candidates for a vast range .
