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Strontium barium niobate thin films with nominal composition corresponding to Sr0.30Ba0.70Nb2O6 (SBN30) were deposited onto Pt/Ti/SiO2/Si(100) substrate by ion beam sputter deposition (IBSD) technique. D–E hysteresis loops for Pt/SBN30/Pt capacitor samples were saturated after annealing treatment in air above 750°C, with remanent polarization (2Pr) value of about 22 μC/cm2 and coercive field (Ec) of about 128 kV/cm. Relative permittivity and leakage current characteristics were also determined from C–V and I–V measurements.

Powders of Pb(Mg1/3Ta2/3)O3-Pb(Zn1/3Nb2/3)O3 ceramic system were prepared by a B-site precursor method. Perovskite phase contents and lattice parameters of the system are reported. Weak-field radio-frequency dielectric constants and losses of sintered samples were investigated as functions of composition, temperature, and frequency. Dielectric relaxation and diffuse phase transition behaviors were characterized. Microstructures were examined and correlated with dielectric characteristics.

The reaction sequences of B-site precursors and perovskite phase formation, crystallographic data, dielectric properties, and microstructures in the PFW-PFN system are reported. The formations of B-site precursors and perovskite phases were studied by X-ray diffraction. B-site precursors formed directly from the constituent oxides or through a competition with a pyrochlore-type structure, while perovskite phases were developed through a competition with pyrochlores. Maximum dielectric constants and Curie temperatures (@100 kHz) of PFW and PFN were found as 8,400 and 23,000 at −71° and 110°C, respectively. PFW exhibited a typical relaxor behavior, whereas PFN showed little relaxation.

In this study, a temperature stable high dielectric ceramic capacitor was made by compositional fluctuation control. Dielectric property was examined by controlling mixing method and volume fraction of PMN, 0.9PMN-0.1PT, and 0.8PMN-0.2PT, each of which is the relaxor material of-10°C, 50°C, and 100°C maximum of dielectric constant respectively. It shows the most temperature stable characteristic at the composition of 0.5:0.2:0.3 volume fraction when the mixing method is parallel. And it shows flat dielectric constant of 10,000 in the range of-10°C to 100°C.

Powder mixtures of end members in MgO-TiO2-Al2O3 ternary system and those of binary (1−x)Mg2TiO4-xAl2O3 were prepared corresponding to 0≤x ≤0.5 in subsolidus tie triangle of MgTiO3-Mg2TiO4-MgAl2O4 and the reaction sequence, sintering and dielectric properties of which were studied. In both cases, MgTiO3(er=17) as the second phase increased and the composition of the solid solution grains concurrently shifted toward MgAl2O4(er=8) with increasing Al2O3 content, which resulted in sluggish decrease in er. Significant difference in microstructure, however, was seen between the two methods probably due to the difference in the reaction sequences.

Lead-cadmium-niobate ceramics Pb(Cd1/3Nb2/3)O3 are difficult to prepare because of the formation of a pyrochlore phase which is detrimental to the dielectric properties. The addition of 0.1 to 0.25 BaCO3 stabilizes the perovskite phase in PCN. Maximum dielectric constant appeared with x=0.1 in Pb1–xBax(Cd1/3Nb2/3)O3 system. Curie temperature of these system decreased with increasing amount of substituted Ba2+ ions (x).