LAUSR

Abstract Vertical silicon nano-pillars (Si N-Pls) inside the cylindrical trenches have been fabricated as a prospective platform for the development of silicon nanowire based devices. Deep reactive ion etching (DRIE) has been used to etch these features in a silicon substrate. In the present case, the fabricated Si N-Pls are ~15 μm in length and 200–500 nm in diameter, while the trenches are of the diameter 12–25 μm. Alumina (Al2O3) discs of 50 nm thickness and diameter in the range of 200–500 nm, obtained via e-beam evaporation, have been used as a hard mask for defining the Si N-Pls during DRIE. Further, a proof of concept has been provided for obtaining electrical contact to the top-ends of these vertically oriented nano-pillars. The proposed platform involving nano-pillars in trenches can be extended for realizing microfluidic-channels containing an array of vertically oriented and electrically addressable silicon nanowires for several applications including chemical sensing.