Conduction Behaviors of CaBi4Ti4O15 Thin Films Prepared by Using Chemical Solution Deposition

The ferroelectric CaBi4Ti4O15 (CBT), all Aurivillius family with n = 4, thin film was prepared on a Pt(111)/Ti/SiO2/Si substrate by using chemical solution deposition followed by rapid thermal annealing at 650 degrees C for 3 min in all oxygen atmosphere. The CBT film was found to be randomly oriented without, any observable secondary phases. The electrical properties of the CBT films were investigated systematically The CBT thin film exhibited a good P-E hysteresis loop with a large remanent polarization (2P(r)) of 54 mu C/cm(2) and a low coercive field (2E(c)) of 168 kV/cm at an electric field of 250 kV/cm. The dielectric constant and the dielectric loss were 390 and 0.028, respectively, at 100 kHz. According to the T-E curves of the CBT thin film, the current conduction mechanisms were found to be dominated by Ohmic and Schottky emission conductions at low and high electric fields, respectively. Furthermore, the values of the pulse polarizations [i.e., +(P* -P<boolean AND>) or -(P* -P<boolean AND>)] of the film were reasonably unchanged up to 1.4 x 10(10) switching cycles.