PREPARATION OF BISMUTH TITANATE FILMS BY ELECTRON-CYCLOTRON-RESONANCE PLASMA SPUTTERING-CHEMICAL VAPOR-DEPOSITION

Bismuth titanate (Bi4Ti3O12:BIT) thin films were prepared on the Pt courted MgO(100) substrate by electron cyclotron resonance plasma sputtering-chemical vapor deposition (ECR plasma sputtering-CVD). Bi2O3 was used as a sputtering target and tetra-isopropoxy-titanium [Ti(i-C3H7O)(4)] as a CVD source. The composition of films was controlled by changing RF power (P-RF) of Bi2O3 target and Ti source temperature (T-Ti). The stoichiometric BIT film was prepared under the condition of P-RF=500W, T-Ti=63 degrees C, deposition temperature of 650 degrees C and deposition rate of 14 nm/min. Epitaxial relationships between the BIT film and the substrate were determined MgO(100)//Pt(100)//BIT(001) and MgO<100>//Pt<100>//BIT<110>. The remanent polarization and coercive field measured by a Sawyer and Tower bridge circuit at 50 Hz were 1.12 mu C/cm(2) and 46 kV/cm, respectively.