Dependence of substrate orientation and etching conditions on the formation of Si nanowires

Silicon nanowires (SiNWs) have received great interest because of their excellent electrical, mechanical, and optical properties as well as their potential applications, ranging from nano/micro-electromechanical system to optoelectronics, and biological/chemical sensors [1–2]. One of the common methods to synthesize Si nanowire arrays directly from bulk silicon wafers is through electroless etching. However the difficulties faced in this method are achieving good control over the distribution and size of the nanowires.