Figure 2

Position-dependent AFM images. Three-dimensional AFM images, recorded on the patterned field on the positions as indicated in the inset on the upper right corner of the figure starting from close to the middle of the field (a) and approaching the border (b,c,d,e,f,g). The white arrows highlight positions of the islands in the <110> directions at the rim of the {111} pits. Progressive nucleation of the islands at the at the four pit-edges is highlighted by the white dashed ring at one example pit.