Realization of an Antireflection Nanopore Array for Black Si Solar Energy Utilization

We demonstrate that an antireflection nanopore arrays were fabricated for black Si solar energy utilization using the highly ordered anodic aluminum oxide (AAO) masks. We have studied the optical characteristics of antireflection nanopore arrays and polished Si. It is found that the reflectivity of the surface of as-prepared Si nanopore arrays decreases from around 22% to less than 1% in the wavelength region from 300 to 1100 nm. The achieved excellent antireflection property compared with polished Si can increase solar cell efficiency, our inexpensive Si production method would lower the cost of solar-grade Si materials.