Ferroelectric Bi 3.99 Ti 2.97 V 0.03 O 12 Thin Films Prepared by Pulsed Laser Deposition

Vanadium-modified bismuth titanate Bi3.99Ti2.97V 0.03O12 (BTV) thin films of about 400 nm thickness were grown on Pt (111)/TiO2/SiO2/Si (100) substrates using the pulsed laser deposition technique. The hysteresis, fatigue and retention behavior of the BTV films were investigated. The appearance of the (117) and (0010) reflections in the x-ray diffraction pattern indicates that the crystalline phase is formed at a low temperature of 600°C. Scanning electron microscope observations reveal that the films annealed at higher temperature have a larger grain size. The films annealed at 650°C exhibits a well defined hysteresis loop with remnant polarization 2Pr and coercive field Ec of 42 μC/cm2 and 110 kV/cm, respectively. The polarization fatigue performance of this film is reasonable at an applied voltage of 7 V (∼170 kV/cm), but it deteriorates at higher electric fields. At an applied electric field of 250 kV/cm, the BTV film shows good retention characteristics up to 105 s. At 100 kHz the relative permittivity and loss factor are 204 and 0.014, respectively.Department of Applied Physic