Figure 5

Photograph and SEM images of wafer-scale Si nanostructures formed by the combined approach of SRNIL and MCEE. (a) Photograph of a 4″ Si wafer consisting of 32 arrays of hexagonally ordered hexagonal Si nanopillars. (b) SEM image showing the hexagonal long-range order of the Si nanopillars. Inset shows the cross-sectional SEM image of the Si nanopillars showing the relatively straight sidewalls and NIL mask cap. (c) SEM plan view of the Si nanopillars (approximately 160-nm wide) showing the NIL mask cap on the top surface of each structure.