The coarsening of Ag films on Ag(100) at room temperature occurred mainly via the diffusion-mediated coalescence of 2-dimensional adatom clusters (rather than via Ostwald ripening) up to a coverage of 0.65 of a monolayer. Above 0.8 of a monolayer, the vacancy clusters coarsened mainly via Ostwald ripening; due to their much lower diffusivity. An asymmetrical transition region separated these 2 regimes and was characterized by a near-percolation structure which underwent self-similar coarsening.

J.M.Wen, J.W.Evans, M.C.Bartelt, J.W.Burnett, P.A.Thiel: Physical Review Letters, 1996, 76[4], 652-5