Boron and zinc oxide (ZnBO) glass added in dielectric materials have drawn a great attention recently due to the low firing temperature. Microwave dielectric properties of the Ba 2 Ti 9 O 20 -based ceramics with ZnBO addition up to 3 wt% were investigated at the sintering temperatures ranging from 900 to 960 C. Effects of the ZnBO addition on the bulk density, microstructure, and dielectric properties of the Ba 2 Ti 9 O 20 -based ceramics at microwave frequency were elucidated. X-ray diffraction (XRD) results show the presence of five crystalline phases, in the sintered ceramics, depending upon the amount of ZnBO addition. Optimum dielectric properties were obtained for the Ba 2 Ti 9 O 20 -based ceramic with 1 wt% ZnBO addition and sintered in air at 940 C for 2 h, having the dielectric properties: Q ¼ 1137 (Q Â f ¼ 8300), " r value ¼ 27:3, and f ¼ 2:5 ppm/ C.

The effects of Bi2O3 addition on the microwave dielectric properties and the microstructures of Zn0.95Mg0.05TiO3 + 0.25TiO2 with 1 wt% 3ZnO–B2O3 (ZnBO–ZMT') ceramics prepared by conventional solid-state routes have been investigated. In a preliminary study, it was shown that ZnBO–ZMT' ceramics can be sintered to a theoretical density higher than 95% at 900°C. In this study, the effects of Bi2O3 additions of up to 10 wt% on the sintering characteristics of the ZnBO–ZMT' ceramics was investigated at the sintering temperatures ranging from 860 to 960°C. Sintered ceramic samples were characterized by X-ray diffraction and scanning electron microscopy (SEM). It was found that as the content of Bi2O3 increases, the density of the sintered ceramics increases, and the sintering temperature can be lowered to 880°C by adding 5 wt% Bi2O3. The ZnBO–ZMT' ceramic with 5 wt% Bi2O3 addition sintered at 880°C exhibits the optimum dielectric properties: Q×f=4000 GHz, ε r=24.6, and τf=-14 ppm/°C. Unlike the ZnBO–ZMT' ceramic without Bi2O3 addition sintered at above 920°C, the ceramics with Bi2O3 additions show no Zn2TiO4 existence at 960°C sintering. It is therefore demonstrated that the addition of Bi2O3 can suppress the formation of Zn2TiO4 in ZnBO–ZMT' ceramics.

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Thin films of zinc titanate (ZnTiO3) can be produced on Si(100) substrates at room temperature by DC reactive magnetron co-sputtering with Ti, Zn as the target and O2 as a reactive gas. In this work, the influence of annealing temperature (500–900 °C) on microstructure and formation of ZnTiO3 thin films were investigated. The samples are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, atomic force microscopy, electron spectroscopy for chemical analysis. As-deposited films have an amorphous columnar structure. The crystallization phenomenon was observed with annealing temperature of 500 °C. After 600 °C 2 h annealing, crystalline phase with ZnTiO3 (hexagonal) and TiO2 (rutile) could be obtained and coexisted. Furthermore, the unit cell size of the ZnTiO3 and TiO2 crystal is a = ~5.062 Å, c = ~ 13.87 Å and a = ~4.58 Å, c = ~ 2.95 Å.

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