A scanning tunnelling microscopic study was made of the nucleation and growth of Au islands on (100). It was shown that reconstruction of the substrate produced strongly anisotropic effects. A rate-equation analysis of the island density suggested that there existed a critical size of 3 at temperatures of between 315 and 380K. At temperatures above 400K, the critical size was greater than 3. The results also suggested that strongly anisotropic diffusion occurred parallel to the reconstruction rows, with an activation energy of about 0.2eV.

S.Günther, E.Kopatzki, M.C.Bartelt, J.W.Evans, R.J.Behm: Physical Review Letters, 1994, 73[4], 553-6