Microstructure and ferroelectric properties of Bi3.2Y0.8Ti3O12 thin films prepared by sol-gel method

作者：Kao M C^*; Chen H Z; Young S L; Shi J B; Lin C H

来源：Journal of Crystal Growth, 2008, 310(10): 2520-2524.

DOI：10.1016/j.jcrysgro.2008.01.039

• sol-gel process
• bismuth titanate
• fatigue
• ferroelectric

Yttrium-substituted bismuth titanate (Bi3.2Y0.8Ti3O12, BYT) thin films were successfully deposited on Pt(1 1 1)/Ti/SiO2/Si(1 0 0) substrates by spin coating with a sol-gel technology and rapid thermal annealing. The effects of annealing temperature (500-800 degrees C) on microstructure and electrical properties of thin films were investigated. X-ray diffraction analysis shows that the BYT thin films have a bismuth-layered perovskite structure with preferred (1 1 7) orientation. The intensities of (1 1 7) peaks increases with increasing annealing temperature. With the increase of annealing temperature from 500 to 800 C, the grain size of BYT thin films increases. The highly (117)oriented BYT thin films exhibit a high-remnant polarization (2P(r)) of 58 mu C/cm(2) and a low-coercive field (2E(c)) of 116 kV/cm, fatigue free characteristics up to > 10(8) switching cycles. The leakage current density (J) were 4.38 x 10(-8) A/cm(2) at 200 kV/cm. These results indicate that the highly (1 1 7)-oriented BYT thin film is useful in nonvolatile ferroelectric random access memory applications.

• 出版日期2008-5-1