A pattern of trenches and wires, oriented along <100> directions, formed during the epitaxial growth of GeSn alloys on Ge(100). The trenches appeared as self-avoiding random walks at low densities, and became organized into domains at higher densities. The patterns were believed to be caused by the migration of Sn islands on the surface, as induced by the diffusion of Ge from one side of the Sn islands to the other. This morphological evolution was suggested to be a kinetic pathway for the phase separation of strained thin films, and might be exploited for the rapid creation of nano-scale patterns.

X.Deng, B.K.Yang, S.A.Hackney, M.Krishnamurthy, D.R.M.Williams: Physical Review Letters, 1998, 80[5], 1022-5