| In this thesis, the PLCT(x) nanometer-powder and nanometer-ceramics, PLCT(x) ferroelectric thin films and PLCT(x)/Pt/Ti/SiO2/Si multilayer hetero-structures were prepared by Sol-Gel technique using inorganic salts and singular metal alkoxide. The dependences of the crystal structures, the surface morphology, the chemical compositions, the thickness of the thin films with the annealing parameters of PLCT(x) nanometer-powder, nanometer-ceramics and ferroelectric thin films were studied by means of modern analysis techniques, such as XRD, SEM, RAMAN, AFM, RBS, gram size analysis, ellipsometer. The relationships between the dielectric constant, the dielectric loss and frequency of PLCT(x) ceramics, and the hysteresis loops of PLCT(x) thin films were measured. The following research results were obtained:1. After many studies and analysis, the optimum processes were obtained for preparing PLCT(x) nanometer-powders with pure perovskite structure by Sol-Gel technology using inorganic salts and singular metal alkoxide. The results of analysis and measurements show that the grain size of nanometer-powders was distributed uniformity. The crystal lattice's axial ratio of PLCT(x) nanometer-powders was near to 1 with the increase of the concentration of calcium.2. The PLCT(x) ceramic pellets were prepared by using nanometer-powders, and then annealed at 1000? for two hours or at 1100? for two hours. The structure of the ceramic pellets annealed at 1100? for two hours show almost pure perovskite phase. The ceramic pellets have straw yellow luster at the edge of theceramic pellets. The mechanic intensity of the ceramic pellets is rather high. It is indicated that the crystal particle of the PLCT(x) ceramic is distributed uniformly by SEM observation. The surface of ceramic is smooth, densification and no crackle. Therefore, the optimum sintering technique of the PLCT(x) ceramic is at 1100? for two hours.3. The dielectric constant and the dielectric loss of the PLCT ceramics with different composition were measured at different frequency. It was found that the dielectric constant decreases with increasing frequency, but increases with the contents of Ca increasing. The dielectric constants of PLCT ceramics before polarizing are a bit smaller than that of PLCT ceramic after polarization with same composition. The dielectric loss of the PLCT ceramics after polarization increases firstly, and then decreases with increasing frequency. It dues to the main loss mechanism of PLCT ceramics is caused by the defect dipole, which movement is a heat-activation process under the alternating electric field.4. The solutions and ferroelectric thin films of PLCT(x) were prepared by Sol-Gel technology. The thickness, extinction and reflection coefficients of the PLCT(x) thin films with variant layers were measured by ellipsometer. It is shown that the thickness of PLCT(x) is non-linear increased with increase of layers. The extinction coefficient of the thinner PLCT(x) films is relative big. On the other hand, the extinction coefficient of the thicker of PLCT(x) films is relative small. The refraction coefficients of the PLCT(x) thin films decrease with increasing thickness, and increase with increasing the Ca concentration x.5. The surface morphology of the varied thickness of PLCT(15) thin films were observed by using AFM. The surface roughness is about 1.5 nm for the PLCT(x) thin films of 46nm thickness annealed at 600 ?,. For the PLCT(x) thin films of 46nm thickness annealed at 700 ?, even though the scanning area is 10 ? m, the surface roughness is still below 5 nm.6. The composition of the PLCT(x) thin films were measured by RBS. The experiment results indicate that stoichiometry of the PLCT(x) thin films is ratherconsistent with the theoretic computation.7. The coercive field of the PLCT(x) thin films, Ec is about to 104V/cm, the remnant polarization Pr is about to 4.5~7.5?C/ cm2, and the ratio (Pr/Ps) of the hysteresis-loop is about to 90%.
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