Fig. 1
From: Droplet etching of deep nanoholes for filling with self-aligned complex quantum structures
Self-assembly of nanoholes in AlGaAs surfaces by local droplet etching with Al. a Schematics of Al droplet formation during Al deposition. b Droplet etching by diffusion of As from the substrate into the droplet material during postgrowth annealing. c Final hole surrounded by an AlAs wall and planar AlAs layer caused by spreading of the initial droplet material. d AFM micrograph of an AlGaAs surface after Al droplet etching at temperature T = 630 °C, Al coverage θ = 1.8 ML, and As background pressure F As < 10 −7 Torr. e Perspective and enlarged view of a nanohole from d