ELECTRICAL PROPERTIES OF Bi4-xLaxTi3O12 FERROELECTRIC THIN FILMS PREPARED BY METALORGANIC DECOMPOSITION METHOD

Bi4-xLaxTi3O12 (BLT) ferroelectric thin films were prepared on a Pt/TiOx/SiO2/Si substrate using metalorganic decomposition (MOD) method, and their electrical properties were evaluated with thickness, composition, and crystallization annealing temperature. Irrespective of the preparation conditions, BLT films were c-axis oriented, and had a dense surface morphology without pore to produce smooth Pt/BLT/Pt interfaces of capacitor. The film thickness was controlled as 90 nm to obtain a low coercive voltage (2Vc) without the problem of capacitor short-fail. The proper composition of Bi3.35La0.85Ti3O12 was selected for the largest switching polarization, good fatigue endurance and a low leakage current density. After crystallization annealing at 700 C, the optimized film of 90 nm Bi3.35La0.85Ti3O12 showed good electrical properties. 10 refs.