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We have simulated grain growth process of an Al ultra thin film by the phase field method. As the model of the calculation, we used the poly crystal model of Kobayashi-Warren in which the phase field and the orientation field are considered. The section of the thin film was divided into 2-dimensional meshes and the time developing equations of the phase field and the orientation field were solved numerically. The parameters for the present calculation have been determined to fit to the results of the grain growth experiment of Al thin film. The relaxation time of grain rotation, only the phase field parameter assumed to be temperature dependent, was determined from the time evolution of averaged grain size in the annealed Al thin film. Isothermal annealing process at various temperatures has been examined using the tuned phase field parameters and the temperature dependence of grain growth was clearly observed.

Phase field simulation on directional solidification of succinonitrile (SCN)-acetone organic model alloy was performed. The development of concentration and phase field profile was calculated in order to clarify the dependences of growth velocity V and temperature gradient G on the morphology of growing crystal.Concerning the primary dendrite arm spacing, 1 , the relationship between 1 4 G 2 V=kÁT 0 and V was examined, where k and ÁT 0 are partition coefficient and temperature difference between liquid and solid phases, respectively. The calculated values of 1 4 G 2 V=kÁT 0 did not show a universal relationship but the trends of the present calculation can be understood by extrapolation from experimental data. The power law index of V for the 1 4 G 2 V=kÁT 0 -V plot took similar values between the experiments and the present calculation for some cases. The 1 -V relationship did not show dependences on temperature of the low temperature side and nor acetone concentration. For the curvature radius R, the R-V relationship can be fitted by a simple function regardless the value of G. In addition, the calculated values of R and the power low indexes of V for R were compared to the dendrite growth theory and good accordance was confirmed.

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