Controlled Synthesis of Horizontal Silicon Nanowires for Biosensor Application

Abstract

Top-down silicon nanowire ( SiNW ) fabrication mechanisms for connecting electrodes are widely utilized because they provide good control of the diameter to length ratio. The representative mechanism for the synthesis of SiNWs , a top-down approach, has limitations on the control of their diameter following lithography technologies, requires a long manufacturing process and is not cost-effective. In this study, we have implemented the bottom-up growth of horizontal SiNWs ( H-SiNWs ) on Si / SiO 2 substrates directly by plasma enhanced chemical vapor deposition (PECVD) under about 400°C. The HAuCl4 solution as a catalyst and SiH 4 gas as a precursor are used for the synthesis of H-SiNWs . After optimization of synthesis conditions, we evaluated the photoelectric properties of the H-SiNWs under illumination with different light intensities. Further, we demonstrated the feasibility of H-SiNW devices for the detection of biotinylated DNA nanostructures and streptavidin interaction.