This paper discusses the difference of phase formation and transition kinetics in post deposition annealing (PDA) and post metal annealing (PMA) of HZO films by employing synchrotron-based in-situ x-ray diffraction measurements. It is found that tetragonal-orthorhombic-monoclinic phase transition occurs throughout annealing process for PDA ones, but only exists in cooling for PMA samples. These results provide new insights into engineering the ferroelectricity of HZO film with different conditions.