We consider the coarsening of surface nanostructures which possess a minimum in formation energy per atom as a function of island size. The time evolution of the island size distribution function is evaluated using an approach based on a Fokker-Planck equation. Competition between chemical potential driven drift and thermal diffusive broadening of the island size distribution results in narrow Gaussian-like metastable states. The existence of these states, which allow the possibility of tuning the mean island size through the incorporation of a deposition flux, depends only upon the presence of a positive gradient in island chemical potential with respect to island size. Such behavior has important implications for the fabrication of uniformly sized quantum dot arrays with size selectivity. © 2007 The American Physical Society.
|Journal||Physical Review B: Condensed Matter and Materials Physics|
|Publication status||Published - 13 Feb 2007|