A thin film deposition dimensionless model for flat planetary fixture is developed.Optimal geometric configurations with theoretical representative radial uniformity are acquired by analyzing the evaporating source location L/H,the distance between the main axis and the secondary axis P/H,the slope angle of fixture A and the emissive characteristics of vapor source N.An optimum design zone is shown by evaluating optimal geometric configurations with coating materials efficiency,angular uniformity and emissive characteristics sensitivity.The results indicate that the thickness via angular distribution is more uniform as L/H+P/H is small and the coating material efficiency is higher when both L/H+P/H and A are small;As L<P and A=-15deg,the optimal geometric configurations are more insensitive to N;As L>P,the change of the representative radial distribution due to the change of the emissive characteristics is less than 0.5%.