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Abstract The processes of phase separation and surface segregation which take place during two-component nanocomposite Metal:Carbon thin film growth are analyzed. The mathematical model is proposed which includes the processes of adsorption, phase separation, surface segregation, surface and bulk diffusion. The process of phase separation is described using Cahn-Hilliard equation and the process of surface segregation is described by Gibbsian segregation model. Diffusion in growing film is allowed to occur in a layer of an arbitrary thickness near the surface. The formations of metal clusters, columns or surface layer in matrixes of carbon are shown by the numerical simulations depending on thin film growth conditions. The influence of film composition and deposition temperature on film morphology is analyzed by the presented simulations. The simulation results are compared with experimental data taken from literature where C:Ni thin films were grown at different contents of Ni and substrate temperatures. The simulation results are in a good agreement with the corresponding experimental data. Graphical abstract Unlabelled Image Highlights • A model for phase separation and surface segregation during film growth is proposed. • Modeling results are consistent with experimental results of the C:Ni thin films. • Depending on conditions, model results exhibit layered, columnar, granular patterns. [ABSTRACT FROM AUTHOR]

Abstract: Experimentally observed surface segregation of nickel during Ni:C thin films growth is analyzed by kinetic model. The model is built considering experimental results where microstructure evolution as a function of the substrate temperature and metal content of C:Ni nanocomposite films grown by pulsed filtered cathodic arc deposition is investigated. The kinetic model includes processes of adsorption, chemical diffusion, surface segregation. Chemical diffusion and surface segregation are allowed in a layer near the surface. The experimental depth profile curves taken from literature were fitted by using proposed model. Thereby the values of depth dependent surface segregation and chemical diffusion coefficients are determined in the system. It is shown by modeling that with the increase of temperature the process of nickel surface segregation becomes dominant. [Copyright &y& Elsevier]

In the present paper, the formation of columnar and layered structure during co-deposition of binary thin films is analyzed by kinetic modeling. The kinetic model is based on phase field theory and involves the main processes taking place during binary film growth: adsorption, phase separation, Gibbsian surface segregation, surface and bulk diffusion. The process of phase separation is defined by the Cahn–Hilliard equation, which describes well the kinetics of formation of nanoparticles in binary system with a limited solubility of components. The formation of columns and layers can occur only if other processes such as diffusion and segregation take place. In this paper, the most attention is paid to the formation of multilayered structures during binary components co-deposition, which is experimentally observed, but whose mechanism of formation is not well understood. In the work presented, the mechanism of formation of layers is shown, and the conditions at which this mechanism starts to work are formulated. It is shown that very important aspects are surface segregation of one of the components and depth dependent diffusion. [ABSTRACT FROM AUTHOR]