Sub-monolayer island-sized distributions were observed using scanning tunnelling microscopy, and the nucleation and growth kinetics of islands on the 3 low-index surfaces were analyzed. A comparison with Monte Carlo simulations revealed that, on the (110) and (111)A surfaces, random nucleation was followed by the attachment and detachment of single atoms at island edges. However, on the (001) surface (using As4), nucleation was initiated in the trenches of the 2 x 4 reconstruction; by pairs of Ga atoms. Growth then proceeded over locally filled trenches; again via the capture of pairs of Ga atoms.

A.R.Avery, H.T.Dobbs, D.M.Holmes, B.A.Joyce, D.D.Vvedensky: Physical Review Letters, 1997, 79[20], 3938-41