Dielectric and Ferroelectric Behaviors of (100)-Oriented 0.9Pb(Sc_0.5Ta_0.5)O₃-0.1PbTiO₃ Thin Films

Abstract

0.9Pb(Sc_0.5Ta_0.5)O₃-0.1PbTiO₃ (PSTT10) thin films were deposited on Si(1 0 0) substrate with a LaNiO₃ buffer layer by RF magnetron sputtering technique and post annealed by a two-steps rapid thermal annealing method. Dielectric, ferroelectric behaviors and surface morphology of the films were analyzed. The films show good ferroelectric and dielectric properties which is similar to the PSTT5 thin films. The leakage current behavior of the films is according with Ohm law in a low electric field region, while it satisfies a space-charge limited conduction in a medium electric field region. With the increasing of frequency, the dielectric constant decrease and the dielectric loss increase, which shows a typical relaxor behavior. The dielectric constant of the films in low frequency band can be explained as Rayleigh law. The films exhibits crack free and uniform surface, with roughness of about 17 nm.

Keywords:

• Ferroelectric and dielectric properties
• space-charge limited conduction
• Rayleigh law
• relaxor

Acknowledgments

We wish to thank Dr. Chaoliang Zhang, in the State Key Laboratory of Oral Diseases in Sichuan University, and Mr. Yong Jin, in the College of Materials Science and Engineer of Sichuan University, for help in taking SEM and XRD data, respectively.

Funding

The work was supported by the National Natural Science Foundation of China (60771016 and 51332003) and the scientific research foundation of Mianyang Normal University (QD2013A07), China.