Monte Carlo simulations of ion-enhanced island coarsening

[摘要] Monte Carlo simulations of growth and ion bombardment have been performed to explore the atomistic processes that occur during ion-assisted growth. The primary elements of the simulation are (1) creation of surface defects (vacancies and adatoms) by ion bombardment and deposition, (2) thermally activated motion of surface defects and (3) recombination of surface vacancies and adatoms, We find that a balance of ion bombardment and deposition (where the creation rate of adatom defects is equal to that of surface vacancies) leads to larger islands and more rapid island coarsening than thermal coarsening with no flux of defects, The presence of the defect flux enhances the breakup of clusters, leading to a broad distribution of island sizes. In comparison, thermal coarsening leads to a more uniform distribution of island sizes that increases in size much more slowly. Histograms of the evolution of the island size distribution provide a quantitative measure of the ion-induced increase in the rate of coarsening.

[发布日期] 1997-05-01

[效力级别]  Proceedings Paper