Nickel silicide nanostructures transformed from site-specific silicon nanostructures.

An approach was proposed for fabricating nickel silicide nanostructures by self-aligned transformation from site-specific silicon nanostructures on the silicon-on-insulator substrate. The silicon nanostructures were firstly fabricated through the sequence of electron beam lithography and pattern transfer to silicon with reactive ion etching. The line-width of structures was shrunk by focused ion beam milling technology. Then nickel silicide nanostructures with the line-width of less than 50 nm were obtained on the insulator separation layer by sequential processes of nickel film deposition, rapid thermal annealing and wet-chemical etching. It was shown that 550 degrees C was an optimal annealing temperature to form NiSi nanostructures with low resistivity of about 15 mu Omega.cm. As-formed metallic NiSi nanowire showed stable electrical properties at elevated temperature.