Ramified growth of two-dimensional islands due to misfit strain Original Research Article

Strain-mediated growth of two-dimensional (2D) islands deposited coherently on the surface of an elastically isotropic substrate is studied. From an energetic consideration, it is shown that the island edge is unstable when the island grows to a critical size. The instability is explained as a trigger of island ramifying and splitting observed in experiments. To have a closer look at the dynamic aspects of island growth, a numerical simulation based on phase field method is also performed. The result is consistent with our energetic analysis.