Nucleation and growth process has been studied on atomic scale for the early stage of thin-film growth by means of computer simulation.The island number and its shape vary with a set of control conditions,such as depo...Nucleation and growth process has been studied on atomic scale for the early stage of thin-film growth by means of computer simulation.The island number and its shape vary with a set of control conditions,such as deposition flux R,surface diffusion rate W and coverage.The kinetic parameters p and q obtained from simulation are positive and dependent on the growth process.The transition from the initial steps of nucleation to growth is also explored.The simulation results are consistent with the experiments and the rate equations from nucleation theory.展开更多
Monte Carlo simulations have been carried out to investigate the kinetic growth process of ultrathinfilm.It is found that the area of cluster S(t)grows with time t as tk,where growth exponent k is less than 1 when ave...Monte Carlo simulations have been carried out to investigate the kinetic growth process of ultrathinfilm.It is found that the area of cluster S(t)grows with time t as tk,where growth exponent k is less than 1 when averaged from all clusters.The further results indicate that the cluster growth is nonlinear,i.e.,the bigger the cluster area S is,the faster it grows(the larger the k).Similar results also show the fractal dimension D increases with the increasing S.Both the slope a of lgk-lgS and the slopeδof 1gD-lgS are positive and related to the nucleation and growth kinetics.展开更多
The nucleation of anisotropic Si islands on reconstructed Si(100)(2x1)surface has been studied by computer simulation,in which the anisotropic diffusion rate along different direction of the substrate is included.Some...The nucleation of anisotropic Si islands on reconstructed Si(100)(2x1)surface has been studied by computer simulation,in which the anisotropic diffusion rate along different direction of the substrate is included.Some results such as anisotropic islands formed at various substrate temperatures,the number of islands(including single Si dimers)with different anisotropic diffusion are obtained.It is shown that the shape and number of anisotropic Si islands are dependent obviously on the substrate temperature and the anisotropic diffusion.The simulation results are consistent with the experimental observations.展开更多
A comprehensive simulation model -- deposition, diffusion, rotation, reaction and aggregation model is presented to simulate the formation processes of ramified clusters on liquid surfaces, where clusters can disuse a...A comprehensive simulation model -- deposition, diffusion, rotation, reaction and aggregation model is presented to simulate the formation processes of ramified clusters on liquid surfaces, where clusters can disuse and rotate easily. The mobility （including diffusion and rotation） of clusters is related to its mass, which is given by Dm = Dos^-γD and θm = θos^-γθ, respectively. The influence of the reaction probability on the kinetics and structure formation is included in the simulation model. We concentrate on revealing dynamic scaling during ramified cluster formation. For this purpose, the time evolution of the cluster density and the weight-average cluster size as well as the cluster-size distribution scaling function at different time are determined for various conditions. The dependence of the cluster density on the deposition flux and time-dependence of fractal dimension are also investigated. The obtained results are helpful in understanding the formation of clusters or thin film growth on liquid surfaces.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.49672095Zhejiang Provincial Natural Science Foundation of China under Grant No.198034.
文摘Nucleation and growth process has been studied on atomic scale for the early stage of thin-film growth by means of computer simulation.The island number and its shape vary with a set of control conditions,such as deposition flux R,surface diffusion rate W and coverage.The kinetic parameters p and q obtained from simulation are positive and dependent on the growth process.The transition from the initial steps of nucleation to growth is also explored.The simulation results are consistent with the experiments and the rate equations from nucleation theory.
基金Supported by the National Natural Science Foundation of China under Grant No.49672095.
文摘Monte Carlo simulations have been carried out to investigate the kinetic growth process of ultrathinfilm.It is found that the area of cluster S(t)grows with time t as tk,where growth exponent k is less than 1 when averaged from all clusters.The further results indicate that the cluster growth is nonlinear,i.e.,the bigger the cluster area S is,the faster it grows(the larger the k).Similar results also show the fractal dimension D increases with the increasing S.Both the slope a of lgk-lgS and the slopeδof 1gD-lgS are positive and related to the nucleation and growth kinetics.
基金the National Natural Science Foundation of China under Grant No.49672095Zhejiang Provincial Natural Science Foundation under Grant No.198034.
文摘The nucleation of anisotropic Si islands on reconstructed Si(100)(2x1)surface has been studied by computer simulation,in which the anisotropic diffusion rate along different direction of the substrate is included.Some results such as anisotropic islands formed at various substrate temperatures,the number of islands(including single Si dimers)with different anisotropic diffusion are obtained.It is shown that the shape and number of anisotropic Si islands are dependent obviously on the substrate temperature and the anisotropic diffusion.The simulation results are consistent with the experimental observations.
基金The project supported by the Natural Science Foundation for Young Scientists of Zhejiang Province of China under Grant No. RC02069 .
文摘A comprehensive simulation model -- deposition, diffusion, rotation, reaction and aggregation model is presented to simulate the formation processes of ramified clusters on liquid surfaces, where clusters can disuse and rotate easily. The mobility （including diffusion and rotation） of clusters is related to its mass, which is given by Dm = Dos^-γD and θm = θos^-γθ, respectively. The influence of the reaction probability on the kinetics and structure formation is included in the simulation model. We concentrate on revealing dynamic scaling during ramified cluster formation. For this purpose, the time evolution of the cluster density and the weight-average cluster size as well as the cluster-size distribution scaling function at different time are determined for various conditions. The dependence of the cluster density on the deposition flux and time-dependence of fractal dimension are also investigated. The obtained results are helpful in understanding the formation of clusters or thin film growth on liquid surfaces.
