Two-Dimensional Nucleation with Edge and Corner Diffusions

概要

論文の詳細を見る
The effect of edge and corner diffusions on the morphology and on the density of islands nucleated irreversibly on a flat substrate surface is studied. Without edge and corner diffusion, islands are fractal. As an edge diffusion constant D_c increases, islands tend to take a cross shape with four needles in the (10) direction. Additional corner diffusion with a diffusion constant D_c yields square islands. When D_c is small relative to the surface diffusion constant D_s, the square corner shows the Berg instability to produce hopper growth in the (11) direction. The corner diffusion influences the island number density n. At a deposition flux F with a small D_c, mainly monomers are mobile and n ∝ (F/D_s)^<1/3>. At large D_c, dimers and trimers are also mobile and n ∝ F^<3/7>D_s^<-5/21>D_c^<-4/21>. The F dependence is in good agreement to the rate equation analysis, but the dependence on D_c cannot be explained by the theory.
社団法人日本物理学会の論文
2003-08-15