Electrochemical Synthesis and Modification of Materials

摘要

A new kinetic model for homoepitaxial growth on a singular surface is presented.The model combines the familiar rate equations approach and the concept of a feeding I zone that allows connection between the growth processes occuring in neighbouring monolayers. The model involves the irreversible 2D nucleation, growth and coalescence of islands in each growing monolayer and consists of an infinite set of coupled rate equations for the adatom and island densities and coverage in successive monolayers. The temporal evolution of the surface morphology (rms roughness and RHEED intensity) is studied woth this model. It is shown that the growth mode is fully determined by a single dimensionless parameter = D/J where D and J are the normalized surface diffusion coefficient and deposition flux, respectively. There exist five regions of corresponding the different growth regimes varying from smooth 2D layer-by-layer growth at sufficiently high values of ( 10 ) to very upon Poisson-like random deposition growth at 10 . The extension of the model to the case of heteroepitaxy is also discussed.