Figure 6

Hemispherical reflectance spectra and incidence-angle-dependent reflectance as function of AOI and wavelength of Si nanostructures. (a) Measured hemispherical reflectance spectra of the Si nanostructures fabricated using Si MaCE conditions with the HNO₃, HF, and DI water volume ratios of (i) 5:1:20 v/v/v, (ii) 4:2:20 v/v/v, and (iii) 5:2:20 v/v/v at an etching temperature of 23°C. The insets show 45° tilted-view SEM images for the corresponding Si nanostructures. (b) Incidence-angle-dependent reflectance as a function of AOI and wavelength for the Si nanostructures fabricated using condition (i).