کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1795005 | 1023711 | 2008 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Shape of heteroepitaxial island determined by asymmetric detachment Shape of heteroepitaxial island determined by asymmetric detachment](/preview/png/1795005.png)
Square lattice gas models for heteroepitaxial growth are studied by means of kinetic Monte Carlo simulations, in order to find a possible origin of anisotropic island shape observed in growth experiments of long organic molecules. When deposited molecules form clusters irreversibly at their encounter during surface diffusion, islands grow in a ramified dendritic shape, similar to DLA. Introduction of molecular detachment from edges makes islands compact with smooth edges. Tilting of adsorbed long molecules or steps in a vicinal substrate may induce orientation dependence in the detachment rate of edge molecules from an island. In simulations with orientation-dependent detachment rates, a clear anisotropy in an island shape is observed. Shape anisotropy on a vicinal substrate is enhanced as steps get dense, in agreement to the experimental observation.
Journal: Journal of Crystal Growth - Volume 310, Issue 3, 1 February 2008, Pages 682–687