Controlled synthesis and optical transmission characteristics of silicon nanowires on colloid patterned glass substrates

We report the patterned synthesis of silicon nanowire (SiNW) arrays by controlling the density and position of Au colloids on glass substrates in a nanocolloid-catalyzed chemical vapor deposition (CVD) process. Density-controlled colloidal Au patterns were defined on the substrates by an inverse contact imprinting technique, where the strong attractive force between electrolyte-coated polymer stamp surfaces and Au colloids was exploited for selective removal of Au colloids from contacting regions of the substrate to the stamp. Controlled nanocolloid-catalyzed CVD process led to the growth of SiNWs being rooted in the catalytic patterns and extended over several tens of mu m. In addition, optical transmittance of the SiNW pattern arrays depending on the NW density and the coverage of catalytic patterns were investigated to understand the optical properties of SiNW arrays.