DOI 10.1515/pac-2013-1119      Pure Appl. Chem. 2014; aop Conference paper

Fabrication and enhanced light-trapping properties of three-dimensional silicon nanostructures for photovoltaic applications Abstract: In order to make photovoltaics an economically viable energy solution, next-generation solar cells with higher energy conversion efficiencies and lower costs are urgently desired. Among many possible solu-tions, three-dimensional (3D) silicon nanostructures with excellent light-trapping properties are one of the promising candidates and have recently attracted considerable attention for cost-effective photovoltaic applica-tions. This is because their enhanced light-trapping characteristics and high carrier collection efficiencies can enable the use of cheaper and thinner silicon materials. In this review, recent developments in the controllable fabrication of 3D silicon nanostructures are summarized, followed by the investigation of optical properties on a number of different nanostructures, including nanowires, nanopillars, nanocones, nanopencils, and nano-pyramids, etc. Even though nanostructures with radial p-n junction demonstrate excellent photon management properties and enhanced photo-carrier collection efficiencies, the photovoltaic performance of nanostructure-based solar cells is still significantly limited due to the high surface recombination effect, which is induced by high-density surface defects as well as the large surface area in high-aspect-ratio nanostructures. In this regard