Orientation of Bi_3.2La_0.8Ti₃O₁₂ ferroelectric thin films with different annealing schedules

Abstract

Fatigue-free Bi_3.2La_0.8Ti₃O₁₂ ferroelectric thin films were successfully prepared on p-Si (100) substrates using metalorganic solution deposition process. The orientation and formation of 5-layers thin films were studied under different processing conditions using XRD. Experimental results indicate that increase in annealing time at 700 °C after preannealing for 10 min at 400 °C can remarkably increase (200)-orientation of the films derived from the precursor solutions with two contents of citric acid. Meanwhile, high content of citric acid increases the film thickness and is conducive to the a-orientation of the films with the preannealing, and low concentration of the solution is conducive to the c-orientation of the films without the preannealing.

Keywords

Bi_3.2La_0.8Ti₃O₁₂ / ferroelectric film / technologic condition / orientation

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