Annealing Temperature and Ultraviolet Irradiation Effect on the Ferroelectric Properties of Bi_3.25La_0.75Ti₃O₁₂ Thin Films

Abstract

Bi(3.25)La(0.75)Ti3O12 thin films were prepared on Pt/Ti/SiO2/Si substrates by the metal organic decomposition method. The structural characterizations and the surface morphology observations were carried out applying X-ray diffraction and atomic force microscope, respectively. The annealing temperature and the ultraviolet irradiation effect on the ferroelectric properties were studied. It was found that the remnant polarization (Pr) and the coercive field (Ec) increased with the increase of the applied electric field (E) for all films. With the annealing temperature increasing from 670 degrees C to 750 degrees C, the increase tendency of Pr(E) and Ec (E) got enhanced from 670 degrees C to 720 degrees C, followed by weakened from 720 degrees C at 750 degrees C. These phenomena could be well explained by the different internal strain in films. The remnant polarization and the coercive field showed an obvious decrease when the top electrodes of the thin films were illuminated with UV light due to the screening effect of trapped charge carries.

Influence of Oxygen to Argon Ratio on the Optical Band Gap of Bi3.25La0.75Fe1Ti2O12 Thin Films Deposited by RF Sputtering

“…[12][13][14][15] The electrical and structural properties of bismuth titanate-based oxides have strong sustainability with site-specific substitution owing to their layered structure with alternating Bi 2 O 2 and Bi 2 Ti 3 O 10 layers. 16 The process of manufacture on the superlattice films used pulsed laser deposition (PLD), BiT-LaCoO 3 showed the largest band gap reduction by ∼1 eV.…”