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The microstructure and dielectric properties of the (Ca0.3Sr0.1)Sm0.4TiO3 ceramics with various sintering conditions have been investigated. The compounds were prepared by the conventional solid-state route with various sintering temperatures from 1340 to 1400°C and sintering duration from 3 h. The resultant microwave dielectric properties were analyzed based upon the densification, the X-ray diffraction patterns and the microstructures of the ceramics. The correlation between the microstructures, the microwave dielectric properties and sintering behaviors was also examined. The εr value of 96.7 and Q×f value of 11,600 GHz were obtained for (Ca0.3Sr0.1)Sm0.4TiO3 ceramics sintering at 1370°C for 3 h. The (Ca0.3Sr0.1)Sm0.4TiO3 ceramics had suitable dielectric properties can find applications in microwave devices such as resonator, filter and antenna.

The physical and optical properties of P2O5-Al2O3-ZnO glasses doped with different concentration of Yb3+ ions were investigated. The experimental results indicated that density, chemical durability, glass transition temperature (Tg) and glass softening temperature (Td) of glasses increase with increasing the Yb2O3 content of glasses. However, the coefficient of thermal expansion (α) for glasses decrease with increasing the Yb2O3 content. From the results of Fourier transform infrared spectroscopy, the numbers of (-P-O-P-) bonds decrease and (-P-O-M+-) bonds increase with increasing the Yb2O3 content. Increase of non-bridge oxygen (-P-O-M+-) raise the refractive index of glasses. Moreover, the results of absorption spectra indicate that the absorption peak of glasses are observed at both wavelengths of 916nm and 977nm. As increasing the concentration of Yb2O3, the absorption efficiencies become stronger. In accordance with the results of fluorescence spectra, the fluorescence emission of glasses are detected at wavelengths of 970nm, 995nm, 1020nm and 1048nm, respectively. The intensity of the fluorescence emission peaks significantly decrease at wavelengths of 970nm and 995nm as the concentration of Yb2O3 increases. However, the intensity of the fluorescence emission peaks significantly increase at wavelength of 1048nm under the same condition.

The microstructure and dielectric properties of the complex perovskite Nd(Col/2Ti1/2)03 ceramics with 60P2O5-15ZnO-5La2O3-5Al2O3-5N2O-5MgO-5Yb2O3 glass additions from 1-2 wt% were prepared with the conventional solid-state route have been investigated. The resultant microwave dielectric properties were analyzed based upon the densification, the X-ray diffraction patterns and the microstructures of the ceramics. Doping with 60P2O5-15ZnO-5La2O3-5Al2O3- 5N2O-5MgO-5Yb2O3 glass (up to 2 wt%) can effectively promote the densification of Nd(Co1/2Ti1/2)O3 ceramics at low sintering temperature. A distinct sintering temperature reduction (100-200°C) can be achieved by adding 60P2O5-15ZnO-5La2O3-5Al2O3-5N2O-5MgO-5Yb2O3 glass to the Nd(Co1/2Ti1/2)O3 ceramics. The correlation between the microstructures and the microwave dielectric properties was also examined. The Nd(Co1/2Ti1/2)O3 ceramics with 60P2O5-15ZnO-5La2O3- 5Al2O3-5N2O-5MgO-5Yb2O3 glass additions can find applications in microwave devices requiring low sintering temperature.

CeO2 ceramics with ZnO additions (1 and 2 wt%) were prepared with conventional solid-state route have been investigated. Doping with ZnO (up to 1 wt%) can effectively promote the densification of CeO2 ceramics at low sintering temperature. At 1550 oC, CeO2 ceramics with 1 wt% ZnO addition possesses a dielectric constant ( ε r) of 23.2, a Q×f value of 53000 GHz and a temperature coefficient of resonant frequency (τf) of –47 ppm/oC.

This paper describes microstructure and leakage current characteristics of ZrTiO4 thin films on ITO/Glass substrate were deposited by sol-gel method with a fix per-heating temperature of 250oC for 30min at various annealing temperatures from 600oC to 800oC for 1 hr. The annealed films were characterized using X-ray diffraction. The surface morphologies of annealed film were examined by atomic force microscopy. The dependence of the microstructure and leakage current characteristics on annealing temperature was also investigated.