Efficient light trapping and broadband absorption of the solar spectrum in nanopillar arrays decorated with deep-subwavelength sidewall features.

Silicon nanopillar (NP) arrays are known to exhibit efficient light trapping and broadband absorption of solar radiation. In this study, we consider the effect of deep subwavelength sidewall scalloping (DSSS) on the broadband absorption of the arrays. Practically, the formation of DSSS is a side effect of top-down dry etching of NP arrays of several microns height.