Silicon nanowires by combined nanoimprint and angle deposition for gas sensing applications

In this work, we demonstrate the fabrication of silicon nanowires, with their widths ranging from 22 nm to 110 nm, using the combination of bilayer nanoimprint and angle deposition. The approach makes the widths of the nanowires adjustable, offering an alternative solution for high-resolution, low-cost, and high-throughput fabrication of nanowire sensors. Using this approach, silicon nanowires with different widths are formed on the boron-doped top Si layers of the SOI substrates, and are used as sensing parts of the gas sensors. The Si nanowire sensors with wire widths of 60 nm and 90 nm demonstrate relative sensitivities of 155% and 44% to the testing gas of NO2. (C) 2011 Elsevier B.V. All rights reserved.