Structural and ferroelectric properties of sol-gel deposited Nb-doped Pb[(Sc1/2Nb1/2)(0.57)Ti-0.43]O-3 thin films

Ferroelectric 0.5 mol% Nb-doped Pb[(SC1/2Nb1/2)(0.57)Ti-0.43]O-3 (PSNTN) th in films were successfully prepared by a sol-gel method. The optimal anneal ing temperature for the crystallization of the films was determined by diff erential thermal analysis (DTA). The degree of crystallinity for the films as a function of annealing temperature and thickness was characterized by t he using X-ray diffraction technique. The Curie temperature of the film was 212 degrees C, which is lower than 248 degrees C for bulk PSNTN ceramics. Typical P-E hysteresis was observed in all films annealed above 600 degrees C. The remanent polarization and the coercive field of the 0.4-mu m-thick film annealed at 700 degrees C were 2 mu C/cm(2) and 32 kV/cm, respectively . Both the effect of annealing temperature on the top electrode and the eff ect of polarity on the ferroelectric properties of the PSNTN were investiga ted. Better insulating properties of the films on Pt/Ti, compared to those of the films on Pt/TiO2, are observed.