Abstract:The phase stability of single domain ferroelectric PbTiO3 (PTO) epitaxial thin film as a function of the misfit strain and film thickness is studied and discussed systematically using the dynamic Ginzburg-Landau (DGL) equation by taking surface eigenstrain relaxation and depolarization field. Misfit strain-film thickness phase diagrams for various temperatures and misfit strain-temperature phase diagrams for various film thicknesses are obtained, respectively. The numerical results show that the phase diagrams in high strain zone are markedly different from previous thermodynamic predictions due to misfit dislocations. Especially, we present that there are c-phase and rotational r-phase in a broader misfit tensile strain zone. The results also express that effects of surface and depolarization field obviously shift the paraelectric phase to lower temperature and shrink the ferroelectric phase with decreasing thickness of the films