Optical absorption enhancement in silicon nanohole arrays for photovoltaics

Radial p-n junction structures are of interest in photovoltaics as they decouple light absorption from minority carrier collection. In this study, we design photovoltaic devices based on silicon nanohole arrays. The nanoholes are fabricated using polystyrene sphere lithography, which is a scalable and cost effective method to fabricate silicon nanostructures in large areas. A post-RIE passivation treatment was applied to prevent seriously surface recombination. Optical reflection characteristics of the optimum nanohole array are theoretically investigated to determine a maximum photocurrent output.