“…Surprisingly, the dielectric constant of the films tends to remain stable at a certain frequency for films annealed at other temperatures. This phenomenon can be attributed to the presence of defects in the PZT/PZ multilayer films, which result in different polarization factors and different response frequencies [12,35,36,39]. The dielectric constant at 1 kHz is 118, 127, 155, 212, 274 and 540 for the samples annealed at 450 °C, 500 °C, 550 °C, 570 °C, 600 °C and 650 °C, respectively.…”