SYNTHESIS AND FERROELECTRIC PROPERTIES OF BiFeO₃ THIN FILMS GROWN BY SPUTTERING

ABSTRACT

There is currently significant interest in the field of ferroelectric thin film materials and devices, with a strong focus on the integration of thin films on Si-complementary metaloxide semiconductor (CMOS) for nonvolatile memory (Fe-RAM) applications. With dramatically high remnant polarization value, bismuth ferrite (BiFeO₃) has emerged as one of the most attractive candidates for the storage capacitor layer. In this paper, BiFeO₃ (BFO) thin films have been prepared on a stabilized Pt/Ti/SiO2/Si bottom electrode by RF sputtering. X-ray diffraction (XRD) of the target showed that a single perovskite phase and random polycrystalline structure without impurity or second phase accompanied. The remnant polarization values were measured as functions of working pressure, substrate temperature and the ratio of oxygen to argon, respectively. Optimal conditions for the deposition of BFO films were reported. The best ferroelectrics values have been measured for the sample BFO film.

Keywords:

• BFO
• rf-magnetron sputtering
• deposition parameters

Acknowledgments

This work is supported by the Key program of National Nature Science Foundation of China, No. 90407023. The authors sincerely thank analytical and testing center, Huazhong University of Science and Technology for assistance in XRD.