Effects of Individual Layer Thickness on the Structure and Electrical Properties of Sol-Gel-Derived Ba_0.8Sr_0.2TiO₃ Thin Films

Abstract:

Ba0.8Sr0.2TiO3 thin films were prepared with various individual layer thicknesses using a sol– gel process. The individual layer thickness strongly affected the structure, ferroelectricity, and dielectric properties of the films. The films prepared with an individual layer thickness of 60 nm showed small equiaxed grains, cubic structure, temperature-independent dielectric constant, and no ferroelectricity. The films prepared with an individual layer thickness of 8 nm showed columnar grains, tetragonal structure, good ferroelectricity, and two dielectric peaks in the dielectric constant–temperature curve. The individual layer thickness for layer-by-layer homoepitaxy growth that resulted in columnar grains was <20 nm.

• Periodical: Advanced Materials Research (Volume 621)
• Pages: 23-26
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.621.23
• Online since: December 2012
• Authors: Wei Rao, Ding Guo Li, Hong Chun Yan
• Keywords: Ba_0.8Sr_0.2TiO₃, Ferroelectricity, Gel-Sol Process

References

[1] G. W. Dietz, M. Schumacher, R. Waser, S. K. Streiffer, C. Basceri, and A. I. Kingon, Leakage Currents in Ba0. 7Sr0. 3TiO3 Thin Films for Ultrahigh Density Dynamic Random Access Memories, J. Appl. Phys. 82 (1997)2359–2364.

DOI: 10.1063/1.366045

[2] R. W. Whatmore, P. C. Osbond, and N. M. Shorrocks, Ferroelectric Materials for Thermal IR Detectors, Ferroelectrics. 76(2004)351–367.

DOI: 10.1080/00150198708016956

[3] C. M. Chu and P. Lin, Electrical Properties and Crystal Structure of (Ba, Sr)TiO3 Films Prepared at Low Temperatures on a LaNiO3 Electrode by Radio-Frequency Magnetron Sputtering, Appl. Phys. Lett. 70 (2007)249–251.

DOI: 10.1063/1.118380

[4] S. Yoon, J. Lee, and A. Safari, Preparation of Thin Film (Ba0. 5Sr0. 5)TiO3 by the Laser Ablation Technique and Electrical Properties, J. Appl. Phys. 76 (2008)2999–3003.

[5] C. S. Chern, S. Liang, Z. Shi, S. Yoon, A. Safari, P. Lu, B. H. Kear, B. Goodreau, T. Marks, and S. Hou, Heteroepitaxial Growth of Ba1-xSrxTiO3/YBa2Cu3O7-x by Plasma-Enhanced Metalorganic Chemical Vapor Deposition, Appl. Phys. Lett. 64 (2010).

DOI: 10.1063/1.111332

[6] D. M. Tahan, A. Safari, and L. Klein, Preparation and Characterization of BaxSr1-xTiO3 Thin Films by a Sol–Gel Technique, J. Am. Ceram. Soc. 79 (2010)1593–1598.

DOI: 10.1002/chin.199643013

[7] B. A. Baumert, L. -H. Chang, A. Matsuda, C. Tracy, N. Cave, R. Gregory, and P. Fejes, A Study of Barium Strontium Titanate Thin Films for Use in Bypass Capacitors,J. Mater. Res. 13(2011)197–204.

DOI: 10.1557/jmr.1998.0026

[8] S. Hoffmann, U. Hasenkox, R. Waser, C. L. Jia, and K. Urban, Chemical Solution Deposited BaTiO3 and SrTiO3 Thin Films with Columnar Microstructure, Mater. Res. Soc. Symp. Proc. (2010)9.

DOI: 10.1557/proc-474-9

[9] R. W. Schwartz, P. G. Clem, J. A. Voigt, E. R. Byhoff, M. V. Stry, T. J. Headley, and N. A. Missert, Control of Microstructure and Orientation in Solution-Deposited BaTiO3 an SrTiO3 Thin Films,J. Am. Ceram. Soc. 82(2009) 2359–2367.

DOI: 10.1111/j.1151-2916.1999.tb02091.x

[10] H. B. Sharma, H. Sarma, and A. Mansingh, Fatigue in Sol–Gel-Derived Barium Titanate Films, J. Appl. Phys. 85(2009) 341–346.

DOI: 10.1063/1.369453

[11] C. L. Jia, K. Urban, S. Hoffmann, and R. Waser, Microstructure of Columnar-Grained SrTiO3 and BaTiO3 Thin Films Prepared by Chemical Solution Deposition,J. Mater. Res. 13(2008) 2206–2216.

DOI: 10.1557/jmr.1998.0309

[12] M. C. Gust, N. D. Evans, L. A. Momoda, and M. L. Mecartney, In Situ Transmission Electron Microscopy Crystallization Studies of Sol–Gel-Derived Barium Titanate Thin Films, J. Am. Ceram. Soc. 80 (2007) 2828–2836.

DOI: 10.1111/j.1151-2916.1997.tb03200.x

[13] E. K. Akdogan, W. Mayo, A. Safari, C. J. Rawn, and E. A. Payzant, Structure–Property Relations in Mesoscopic BaTiO3 and PbTiO3, Ferroelectrics, 223(2009)11–18.

DOI: 10.1080/00150199908260547

[14] L. Zhang, W. -L. Zhong, C. -L. Wang, P. -L. Zhang, and Y. -G. Wang, Finite-Size Effects in Ferroelectric Solid-Solution BaxSr1-xTiO3,J. Phys. D: Appl. Phys. 32 (2010)546–551.

DOI: 10.1088/0022-3727/32/5/008