Tuning the temperature coefficient of resonant frequency for 8-layer twinned hexagonal perovskite Ba₈ZnTa₆O₂₄ ceramics

详细信息    查看全文

• 作者：Sen Zeng ; Guoqi Ni ; Xiaojun Kuang
• 刊名：Journal of Materials Science: Materials in Electronics
• 出版年：2016
• 出版时间：October 2016
• 年：2016
• 卷：27
• 期：10
• 页码：10078-10081
• 全文大小：682 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chemistry
  Optical and Electronic Materials
  Characterization and Evaluation Materials
  
• 出版者：Springer New York
• ISSN：1573-482X
• 卷排序：27

文摘

High-Q dielectric materials ilmenite MgTiO₃, columbite MgNb₂O₆ and cubic perovskite Ba₃NiTa₂O₉ with negative temperature coefficient of resonant frequency (τ_f) were selected as candidates for compensating the τ_f of hexagonal perovskite Ba₈ZnTa₆O₂₄. X-ray diffraction data shows that Ba₈ZnTa₆O₂₄ coexists with Ba₃NiTa₂O₉ but is not compatible with MgTiO₃ and MgNb₂O₆ at high temperature. The τ_f for the mixed hexagonal/cubic perovskite Ba₈ZnTa₆O₂₄–Ba₃NiTa₂O₉ system is tunable via the temperature compensation effect and its quality factor may be improved via annealing the ceramics at high temperature to enhance the cation ordering in the cubic component. Permittivity ε_r ~ 22–25, Q×f > 30,000 GHz and tunable τ_f within ±10 ppm/°C were achieved in the range of about 50–80 wt% Ba₃NiTa₂O₉ for the hexagonal/cubic perovskite composite Ba₈ZnTa₆O₂₄–Ba₃NiTa₂O₉ ceramics, which is suitable for the application as dielectric resonators and filters.