Phase field modeling of grain growth in thin films on rigid substrates

A phase field model of grain growth in thin films on rigid substrates is presented, in which the motion of grain boundaries is driven by curvatures as well as anisotropy in surface, interface, and strain energies. The match between the proposed model and the corresponding sharp interface model is demonstrated by asymptotic analysis. The effect of diffuse interface on grain boundary mobility is minimized. The parameters in the model are connected to the measurable properties of materials, and therefore can be obtained from experiments or atomic scale simulations. In numerical simulations, the influence of the texture dependent surface, interface, and strain energies on grain growth is illustrated. The effects of film thickness, strain level, and grain boundary grooving on grain size distribution and texture evolution are also investigated. The effectiveness as well as the limits of the present model are discussed, and the ways to extend it are proposed.