We report structural, dielectric, and ferroelectric properties of compositionally graded (Pb,La) TiO3 thin films on LaNiO3/SiO2/Si substrates, where all the films were prepared by the sol-gel technique. The crystalline orientation and surface morphology of the graded films were closely related to the deposition sequence of film layer. Upgraded film exhibited ~100! preferentially oriented growth, whereas downgraded film showed a randomly oriented growth, where the films with La content increasing or decreasing gradually along film thickness from the substrate to the top surface are called "upgraded" or "downgraded" films, respectively. The dielectric constants, for upgraded and downgraded films annealed at 650

Ferroelectric (Bi,La) 4Ti3O12 (BLT) thin films with different Bi2O3 template layers were prepared on Pt/Ti/SiO2/Si substrates by a chemical-solution deposition method. The BLT films with a thin Bi2O3 bottom layer and those with a thin Bi2O3 intermediate layer had a (117) preferentially oriented growth after annealing at 750°C, while those with a thin Bi2O3 upper layer and those without a Bi2O3 template layer exhibited a high c-axis orientation. The surface morphologies changed with different preferential orientations. The electrical measurements showed that the use of Bi2O3 template layers improved significantly the P–E hysteresis loops of BLT thin films. The remanent polarization (2Pr) and coercive field (Ec) values of BLT films without a Bi2O3 template layer, with a Bi2O3 upper layer, with a Bi2O3 bottom layer, and with a Bi2O3 intermediate layer annealed at 750°C were 10.8, 29.12, 26.17, and 19.67mC/cm2; 79.0, 74.5, 75.5, and 76.3kV/cm, respectively, at an applied electric field of 350 kV/cm. The dielectric constants and dissipation factors were 184, 303, 243, and 217; 0.036, 0.044, 0.039, and 0.039, respectively, at the frequency of 100 kHz, for these BLT films without a Bi2O3 template layer, with a Bi2O3 upper layer, with a Bi2O3 bottom layer, and with a Bi2O3 intermediate layer. All the capacitors with Bi2O3 template layers showed good polarization fatigue characteristics at least up to 331010 bipolar pulse cycles and excellent retention properties up to 33104s.

c-Axis oriented zinc oxide thin films were prepared by sol-gel process on fused quartz substrates. The structure, optical and electrical properties of ZnO films were investigated. Growth of the thin films strongly depends on heat-treatment conditions. The c-axis lattice constants of the thin films and the band gap are a little bigger than that of ZnO crystal. The differences between the thin film and crystal might be attributable to the grain boundaries and imperfections in thin films.

Calcium modified lead titanate sol was synthesized using lead acetate trihydrate, calcium nitrate tetrahydrate and titanium tetra-n-butoxide as starting materials, methanol and ethanolamine were elected as solvent and stabilizing or complexing agent, respectively. (Pb0.76Ca0.24)-TiO3 thin films were prepared on platinum-coated silicon and fused silica substrates with the solution using the pinning method. The surface morphology and crystal structure, surface compositions and chemical tates, electrical and optical properties of the thin films were investigated. The films have good composition homogeneity and thickness uniformity. The dielectric constant and dissipation factor of 1 kHz at room temperature were found to be 280 and 0.027, respectively, for thin films with 0.5mm hickness annealed at 6008C for 1 h. The remanent polarization and coervive field were 15 mC/cm2 and 64 kV/cm, respectively. The thin