Numerical simulation of light-trapping and photoelectric conversion in single nanowire silicon solar cells

Single nanowire solar cells (SNSCs) are typical nanoscale optoelectronic devices with unique photonic and electronic properties, which require precise designs in terms of a comprehensive simulation technique. We present a coupled model for silicon-based SNSCs which solves both Maxwell and semiconductor equations self-consistently using the finite-element method. The light-trapping behavior (e.g., leaky-mode resonances) and carrier generation/recombination inside the nanowire cavity are simulated and analyzed especially by addressing the effects of semiconductor doping, surface recombination, and device dimension on the performance of the solar cells. The absorption efficiency, external quantum efficiency, and current-voltage characteristics have been obtained for a complete evaluation of SNSCs.