Preparation of Layer-Structured CaBi2Ta2O9 Ferroelectric Thin Films through a Triple Alkoxide Route

A triple alkoxide solution for CaBi2Ta2O9 (CBT) thin films was prepared. CBT thin films were deposited on Pt-passivated silicon and Pt-passivated quartz glass substrates. The thin films on Pt-passivated silicon crystallized to form the perovskite structure at low temperatures and showed preferred orientation along the c-axis. The thin films did not show ferroelectric P–E hysteresis loops. In contrast, the 750°C-annealed thin film on Pt-passivated quartz glass showed random orientation and exhibited excellent P–E hysteresis loops. The remanent polarization (P r) and the coercive electric field (E c) at 13 V were 6.9 µC/cm2 and 170 kV/cm, respectively.