Effects of annealing schedule on orientation of Bi3.2Nd0.8Ti3O12 ferroelectric film prepared by chemical solution deposition process

Fatigue-free Bi3.2Nd0.8Ti3O12 ferroelectric thin films were successfully prepared on p-Si(1 1 1) substrate using chemical solution deposition process. The orientation and formation of thin film under different annealing schedules were studied. XRD analysis indicated that (2 0 0)-oriented films with degree of orientation of I(2 0 0)/I(1 1 7) = 2.097 and 0.466 were obtained by preannealing for 10 min at 400 °C followed by rapid thermal annealing for 3, 10 and 20 min at 700 °C, respectively, (0 0 8)-oriented films with degree of orientation of I(0 0 8)/I(1 1 7) = 1.706 were obtained by rapid thermal annealing for 3 min at 700 °C without preannealing, and (0 0 8)-oriented films with degree of orientation of I(0 0 8)/I(1 1 7) = 0.719 were obtained by preheating the film from room temperature at 20 °C/min followed by annealing for 10 min at 700 °C. The a-axis and c-axis orientation decreased as increase of annealing time due to effects of (1 1 1)-oriented substrate. AFM analysis further indicated that preannealing at 400 °C for 10 min followed by rapid thermal annealing for 3 min at 700 °C resulted in formation of platelike crystallite parallel to substrate surface, however rapid thermal annealing for 3 min at 700 °C without preannealing resulted in columnar crystallite perpendicular to substrate surface.