Microwave Dielectric Properties of ($1-x$)(Mg0.95Zn0.05)TiO3–$x$Ca0.6La0.8/3TiO3 Ceramic System

概要

論文の詳細を見る
The microstructures and microwave dielectric properties of the ($1-x$)(Mg0.95Zn0.05)TiO3–$x$Ca0.6La0.8/3TiO3 ceramic system were investigated. To achieve a temperature-stable material, we studied a method of combining a positive-temperature-coefficient material with a negative one. Ca0.6La0.8/3TiO3 has the following dielectric properties: a dielectric constant of $\varepsilon_{\text{r}}\sim 109$, a $Q\times f$ of ${\sim}17{,}600$ GHz and a large positive $\tau_{\text{f}}$ of ${\sim}213$ ppm/°C. (Mg0.95Zn0.05)TiO3 possesses a dielectric constant of $\varepsilon_{\text{r}}\sim 16$, a high $Q\times f$ of ${\sim}210{,}000$ (at 9 GHz) and a negative $\tau_{\text{f}}$ of $-60$ ppm/°C. As $x$ varies from 0 to 0.9, the ($1-x$)(Mg0.95Zn0.05)TiO3–$x$Ca0.6La0.8/3TiO3 ceramic system has the following dielectric properties: $16<\varepsilon_{\text{r}}<88$, $32{,}800<Q\times f<210{,}000$ and $-60<\tau_{\text{f}}<205$. By appropriately adjusting the $x$ value in the ($1-x$)(Mg0.95Zn0.05)TiO3–$x$Ca0.6La0.8/3TiO3 ceramic system, a zero $\tau_{\text{f}}$ value can be attained. With $x=0.15$, a dielectric constant $\varepsilon_{\text{r}}$ of ${\sim}26$, a $Q\times f$ value of ${\sim}86{,}000$ GHz (at 9 GHz) and a $\tau_{\text{f}}$ value of ${\sim}0.5$ ppm/°C were obtained for 0.85(Mg0.95Zn0.05)TiO3–0.15Ca0.6La0.8/3TiO3 ceramics sintered at 1320 °C for 4 h.
2006-08-15