Effect of microwave annealing on the polarization properties of sol-gel derived Pb(Zr0.4Ti0.6)O3 epitaxial thin films

In recent years, microwave annealing (MA) has received increasing attention due to its ability to prepare ferroelectric thin films with good electrical properties at low temperatures or in a short period of time. Nevertheless, the direct impact of microwaves on the electrical properties of ferroelectric thin films is not yet fully understood. Here, amorphous Pb(Zr 0.40 Ti 0.60 )O 3 (PZT) thin films were deposited on Nb-doped SrTiO 3 (NSTO) single-crystal substrates by a sol-gel method, and then crystallized by MA. Compared with conventional annealing (CA), the effect of MA on the polarization properties of PZT thin films were studied. The results indicate that MA can weaken the imprint effect of polarization versus electric field ( P - E ) hysteresis loops . Based on the Schottky emission model, the effective built-in potential and depletion layer width at the PZT/NSTO interface were analyzed. It was found that MA can reduce the effective built-in potential and depletion layer width at the PZT/NSTO interface. During MA, the interaction between microwaves and charged defects (such as oxygen vacancies) leads to the aggregation of charged defects at the interface, reducing the interface barrier height and depletion layer width, thereby weakening the pinning of ferroelectric domains near the interface by the built-in electric field. Therefore, MA can not only prepare high-quality ferroelectric thin films at low temperatures or in a short period of time, but also directly influence the polarization properties of ferroelectric thin films. • High-quality PZT epitaxial thin films can be obtained by microwave annealing. • Microwave annealing can weaken the imprint effect of PZT films. • Microwave annealing can weaken the deformation of the P - E hysteresis loop. • The mechanism of microwave annealing to weaken the imprint effect of PZT films.