Moth-eye antireflection coating fabricated by nanoimprint lithography on 1eV dilute nitride solar cell

We report on the performance of biomimicked antireflection coating applied to dilute nitride solar cell. The coating consists of nanostructures replicating the moth-eye geometry and has been fabricated by nanoimprint lithography directly within the window layer covering the dilute nitride absorbing junction. The mean reflectivity within the spectral range of 320-1800nm remains under 5% for incident angles up to 45 degrees. The effect of the coating on the cell performance was assessed by measuring the current-voltage characteristics under simulated solar illumination. A clear performance increase was identified when comparing a solar cell with the moth-eye coating with a solar cell having a standard SiNx/SiO2 coating. Copyright (c) 2012 John Wiley & Sons, Ltd.