Arrayed Si/SiGe nanowire heterostructure formation via Au-catalyzed wet chemical etching method

Abstract

Aligned Si/SiGe nanowire heterostructures have been formed using Au-assisted top-down chemical etching method combined with nanosphere lithography. Since the nanowires are formed from the as-grown films, the heterostructures along the axial axis of the formed nanowires, i.e. axial heterostructures, are replica of the grown layered film structure. Thus SiGe nanowire heterostructures can be readily formed along the axis using an as-grown heterostructured film. By applying a nanosphere lithography technique, the space, diameter, and density of the nanowires can be controlled and readily formed at specifically defined area. Because of the flexibility and simplicity of this method, nanowires with embedded junctions of different doping characteristics and Si/Ge concentrations can be fabricated easily. Si and its Ge alloy nanowires and one dimensional heterostructures formed using this method may have great potential for vertical logic, photovoltaic and memory device applications. ©The Electrochemical Society.