Figure 1.

Representative AFM images of the oxidized silicon surfaces employed in this work. (a) The surface of a comparatively smooth untreated Si(100) wafer with a root mean square (RMS) surface roughness of S_q = 0.2 ± 0.1 nm. (b) After ion irradiation, the silicon surface displays a self-organized ripple pattern and the RMS roughness is increased to S_q = 1.2 ± 0.3 nm. Both images have the same height scale ranging from 0 to 8 nm. The insets show the corresponding FFTs of the images. Below each AFM image, a height profile recorded along the white horizontal line is shown.