Time development during growth and relaxation of amorphous carbon films. Tight-binding molecular dynamics study

Abstract The growth of amorphous carbon (a-C) thin film on a [1 1 1] diamond surface has been studied by a tight-binding (TB) molecular dynamics (MD) technique. Six different three-dimensional networks were constructed with periodic boundary conditions in two dimensions. Time-dependent non-equilibrium growth was simulated with atom-by-atom deposition and it was described as in real experiments without an artificial model of energy dissipation. An additional seventh structure was constructed by a melt quenching procedure which is widely used in computer generations of amorphous networks. The final structures consist of over 100 atoms. Densities, radial distribution functions (RDFs), coordination numbers, bond angle distributions and ring statistics were analyzed. During relaxation the temperature in the amorphous film decreases with stretched-exponential function. The time dependence of bond length and bond angle deviations were also investigated.