Crystallization kinetics of PbTiO3 ferroelectric films: Comparison of microwave irradiation with conventional heating

Lead titanate (PTO) films were deposited onto Pt/Ti/SiO2/Si substrates by a sol-gel method and annealed by microwave irradiation and conventional heating. In contrast to conventional heating, microwave irradiation can crystallize the PTO films at a low temperature of 450 degrees C or at 550 degrees C for only 5 min. The XRD and TEM studies reveal that microwave radiation can reduce the nucleation time, and increase the growth rate of perovskite grains in the crystallization process. Moreover, the results using the Avrami's model show that the effective activation energy for crystallization process by microwave irradiation is 131 kJ/mol, much lower than that for the PTO films by conventional heating (216 kJ/mol). Therefore, microwave irradiation can reduce the effective activation energy for the nucleation and grain growth of the perovskite phase during the crystallization process, contributing to a low-temperature or a short-time preparation process of ferroelectric films.