Ferroelectric Properties and Microstructures of Tb₄O₇-Doped Bi₄Ti₃O₁₂ Thin Films

Abstract:

Tb-doped bismuth titanate (Bi_xTb_yTi₃O₁₂ BTT) thin films were fabricated on Pt/Ti/SiO₂/Si substrates by rf magnetron sputtering technique, and the microstructures and ferroelectric properties of the films were investigated. Microstructure studies indicate that all of BTT films with well-developed rod-like grains consist of single phase of a bismuth-layered structure without preferred orientation. The experimental results indicate that Tb doping into Bi₄Ti₃O₁₂ results in a remarkable improvement in ferroelectric properties. The remanent polarization ( Pr ) and coercive field ( Ec ) of the BTT film with y=0.6 were 22 μC/cm2 and 85 kV/cm, respectively. After 3 × 10¹⁰ switching cycles, 20% degradation of Pr is observed in the film.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1325-1328
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1325
• Online since: June 2012
• Authors: R.F. Liu, X.A. Mei, M. Chen, C.Q. Huang, J. Liu
• Keywords: Bismuth Titanate, Doping, Ferroelectric, Film

References

[1] B. H. Park, B. S. Kang, S. D. Bu, et al. Lanthanum-substituted bismuth titanate for use in non-volatile memories, Nature, 401 (1999) 682-684.

DOI: 10.1038/44352

[2] J. F. Scott, Application of Moden Ferroelectrics, Science, 315 (2007) 954-959.

[3] H. N. Lee, D. Hesse, H. Zakharov, et al. Ferroelectric Bi3.25La0.75Ti3O12 films of uniform a-axis orientation on silicon substrates, Science, 296 (2002) 2006-2009.

DOI: 10.1126/science.1069958

[4] S. Y. Chen, B. C. Lan, C. S. Taso, Effect of titanium substitution on film structure and ferroelectric properties of Sr-deficient Sr0.75Bi2.35Ta2O9 thin films, Thin Solid Films, 422 (2002) 186-192.

DOI: 10.1016/s0040-6090(02)00992-6

[5] Z. H. Bao, Y. Y. Yao, J. S. Zhu, et al. Study on ferroelectric and dielectric properties of niobium doped Bi4Ti3O12 ceramics and thin films prepared by PLD method, Materials Letters, 56 (2002) 861-866.

DOI: 10.1016/s0167-577x(02)00628-6

[6] W. Wang, J. Zhu, X. Y. Mao, Properties of Tungsten-doped Bi4Ti3O12-Sr Bi4Ti4O15 intergrouth ferroelectrics, Mater. Res. Bull. 42 (2007) 274-280.

[7] A. Z. Simoes, C. Quinelato, A. Ries, et al. Preparation of Lanthanum doped Bi4Ti3O12 eceramics by the polymeric precursor method, Mater. Chemistry and Phys. 98 (2006) 481-485.

DOI: 10.1016/j.matchemphys.2005.09.070

[8] U. Chon, K. B. Kim, H. M. Jang, et al. Fatigue-free samarium-modified bismuth titanate (Bi4-xSmxTi3O12) film capacitors having large spontaneous polarizations, Appl. Phys. Lett. 79 (2001) 3137-3139.

DOI: 10.1063/1.1415353

[9] D. Wu, A. D. Li, N. B. Ming, Dielectric characterization of Bi3.25La0.75Ti3O12 thin films, Appl. Phys. Lett. 84 (2004) 4505-4507.

DOI: 10.1063/1.1757631

[10] H. Uchida, H. Yoshikawa, I. Okada, et al. Approch for enhanced polarization of polycrystalline bismuth titanate films by Nd3+/V5+ cosubstitution, Appl. Phys. Lett. 81 (2002) 2229-2231.

DOI: 10.1063/1.1507839

[11] T. Watanabe, H. Funakubo, M. Osada, et al. Effect of cosubstitution of La and V in Bi4Ti3O12 thin films on the low-temperature deposition. Appl. Phys. Lett. 80 (2002) 2229-2231.

DOI: 10.1063/1.1430267

[12] M. Chen, Y. H. Sun, K. L. Su, et al. Dielectric characterization and microstructures of Pr6O11-doped Bi4Ti3O12, Key Engineering Materials, 336 (2007) 155-157.

[13] M. Chen, Y. Wang, Z. L. Liu, et al. Electrical characteristics and microstructures of Sm2O3-doped Bi4Ti3O12, Chin. Phys. Lett. 21 (2004) 1811-1814.