Figure 1

Illustration of the fabrication process of self-assembled Au droplets according to the variation of Au thickness. (a) Atomic force microscopy (AFM) image of bare GaAs (111)A. (b) After Au deposition. (c) Self-assembled Au droplets with 2 nm Au deposition annealed at 550°C. (d) Au droplets with 9 nm Au deposition. AFM images in (a-d) are 1 × 1 μm². AFM side views of (a-1) to (c-1) are 250 × 250 nm² and that of (d-1) is 300 × 300 nm². (a-2) to (d-2) present cross-sectional surface line profiles indicated as white lines in (a-d).