Ferroelectric Properties and Microstructures of Pr6O11-doped Bi4Ti3O12 Thin Films

Pr6O11-doped bismuth titanate (BixPryTi3O12 BPT) 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 BPT films with well-developed rod-like grains consist of single phase of a bismuth-layered structure without preferred orientation. Pr doping into Bi4Ti3O12(BIT) causes a large shift of the Curie temperature (T-C) of paraelectric-ferroelectric phase transition of BIT from 675 degrees C to lower temperature and improvement in dielectric properties. The experimental results indicate that Pr doping into Bi4Ti3O12 results in a remarkable improvement in ferroelectric properties. The remanent polarization (P-r) and coercive field (E-c) of the BPT film with y=0.9 were 35 mu C/cm(2) and 80 kV/cm, respectively. After 3 x 10(10) switching cycles, 20% degradation of P-r is observed in the film.