The Schwoebel-Ehrlich barrier (the additional barrier for an adatom to diffuse down a surface step) dictated the growth modes of thin films. The conventional concept of this barrier was 2-dimensional, with the surface step being one monolayer. The concept of a 3-dimensional Schwoebel-Ehrlich barrier was proposed, and a 2-dimensional to 3-dimensional transition was identified using the molecular statics method. The results showed that substantial differences existed between the 2-dimensional and 3-dimensional barriers, the transition was complete within 4 monolayers and there was a major disparity

in the 3-dimensional barriers between 2 facets. Alteration of this disparity using surfactants could lead to the dominance of surface facet against thermodynamics.

Schwoebel-Ehrlich Barrier - from Two to Three Dimensions. S.J.Liu, H.Huang, C.H.Woo: Applied Physics Letters, 2002, 80[18], 3295-7