Design of surface nanowire arrays for high efficiency thin (≤10 μm) Si solar cells

• Comparative investigations of 10-μm-thick Si solar cells with and without surface nanowire arrays.
• Influence of the diameter and filling ratio of the array on the optical absorption.
• Simulation of spatial distribution of the optical generation rate.
• Suppression of the carrier collection loss caused by the surface recombination.

We investigated the optical characteristics and expected photocurrent of 10-μm-thick Si solar cells with surface nanowire arrays. The diameter and filling ratio of the array influenced not only the optical absorption, but also the spatial distribution of the optical generation rate. Proper design of the nanowire array could locate the high optical field region far from the surface, avoiding serious carrier collection loss and raising the energy conversion efficiency.