Figure 2

Left column shows 1 × 1 μm²3D AFM images of the mounding surface that results after growing a 25-nm thick GaAs cap layer (a) and after 1.4 ML (b), 1.5 ML (c) and 1.6 ML (d) of InAs is deposited on this surface. The inset in (b) corresponds to the derivative image and is shown to highlight the presence of 3D InAs nuclei forming at the top of the mounds. Right column shows 1 × 1 μm²3D AFM images of the mounding surface that results after growing a 100-nm thick GaAs cap layer (e) and after 1.4 ML (f), 1.5 ML (g) and 1.6 ML (h) of InAs is deposited on this surface. See text for the growth conditions of the different GaAs cap layers