Figure 2
From: Fundamental role of arsenic flux in nanohole formation by Ga droplet etching on GaAs(001)
AFM images of ringlike structures before and after As exposure of Ga droplets. (a) 600 × 300 nm2 AFM image of the ring structure, formed at a substrate temperature of 500°C, remaining after the Ga droplet was removed by HCl. (b) 3D representation of the ring structure. (c) 600 × 300 nm2 AFM image of the ring structure and nanohole obtained after annealing the Ga droplet under an As flux of 0.70 ML/s for 30 s. (d) 3D image of the same structure where the facets of the highest structure (main sector) surrounding the ring are clearly seen.