Statistics of adatom diffusion in a model of thin film growth.

摘要: We study the statistics of number executed hops adatoms at surface films grown with Clarke-Vvedensky (CV) model in simple cubic lattices. The distributions this N are determined average thicknesses close to 50 and 100 monolayers for a broad range values diffusion-to-deposition ratio R probability e that lowers diffusion coefficient each lateral neighbor. mobility subsurface atoms energy barriers crossing step edges neglected. Simulations show execute uncorrelated during time which they move on film surface. In low temperature regime, typically Re≲1, attachment neighbors is almost irreversible, scales as 〈N〉∼R^{0.38±0.01}, distribution decays approximately exp[-(N/〈N〉)^{0.80±0.07}]. Similar decay observed simulations random walks plane randomly distributed absorbing traps estimated relation between 〈N〉 density terrace steps similar trapping problem, provides conceptual explanation regime. As increases, crosses over another regime when Re^{3.0±0.3}∼1, indicates high all borders. P(N) change exponential decays, due constant an adatom become immobile after being covered by new deposited layer. At higher temperatures, surfaces very smooth 〈N〉∼Re^{1.85±0.15}, explained analogy submonolayer growth. Thus, growing related universal nonuniversal features growth properties models if hopping limited landscape not deposition other layers.