Hierarchical antireflective surface of silicon substrates for tandem solar cells

The structural and optical properties of tandem silicon/perovskite structures with a hierarchical antireflective surface at the interface have been studied. The surface consisted of micro-sized pyramids and nano-sized short needles, formed respectively by chemical and reactive ion etching of silicon substrates. It is shown that a perovskite film without pores and voids covers a hierarchical surface with high conformity. The manufactured samples are characterized by low reflectance over a wide range of radiation wavelengths