Stochastic Simulation of the Fluctuation Stage in the Formation of Thin Films

摘要

The creation of coatings with given properties, which are important in the areas of microelectronics and the nanomodification of surfaces, depends on the initial distribution of the adsorbing layer of particles deposited on the surface. The nucleation of thin-film islands is simulated in a numerical stochastic experiment. Adsorbed-material islands assume the properties of coating due to a heterogeneous phase transition at the fluctuation stage that lasts no longer than 10"4 s; this phase transition is a strongly nonequilibrium process of the formation of clusters of new-phase nuclei. The rate of this process, as well as the homogeneity of the coating that arises, is governed by the temperature of the substrate and the plasma (or gas) flux fluence on the surface, as well as by certain crystal-lattice properties, such as its degree of anisotropy and elastic properties, the density of defects responsible for porosity, the presence of dislocations, and the potential of the interface between the solid substrate and plasma.