Abstract Na 5 Y(MoO 4 ) 4 and Na 5 Yb(MoO 4 ) 4 ceramics are prepared by solid state ceramic route and structural characterization has been done using powder X-ray diffraction and Laser Raman spectroscopy techniques. The presence of MoO 4 2- units in the crystal structure is confirmed from Raman spectra. The scanning electron micrographs of the sintered ceramic samples show dense microstructure. Na 5 Y(MoO 4 ) 4 ceramic exhibited a maximum sintered density of 3.6 g/cm 3 at 600 °C with a dielectric constant of 7.8, quality factor (Q × f) of 56,800 GHz, and temperature coefficient of resonant frequency (τ f ) of −83 ppm/°C, whereas Na 5 Yb(MoO 4 ) 4 ceramic showed a maximum sintered density of 3.9 g/cm 3 at 570 °C with a dielectric constant of 6.9, quality factor (Q × f) of 43,400 GHz, and temperature coefficient of resonant frequency (τ f ) of −68 ppm/°C. Powder X-ray diffraction and energy dispersive X-ray spectroscopic analyses of the co-fired samples confirm good chemical compatibility with aluminium electrode for Na 5 Yb(MoO 4 ) 4 ceramic and hence is a suitable candidate material for ULTCC applications.

中文翻译：

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用于 ULTCC 应用的 Na 5 M(MoO 4 ) 4 (M = Y,Yb) 微波陶瓷的合成和表征

摘要 采用固态陶瓷法制备了Na 5 Y(MoO 4 ) 4 和Na 5 Yb(MoO 4 ) 4 陶瓷，并利用粉末X射线衍射和激光拉曼光谱技术进行了结构表征。MoO 4 2-单元在晶体结构中的存在由拉曼光谱证实。烧结陶瓷样品的扫描电子显微照片显示出致密的微观结构。Na 5 Y(MoO 4 ) 4 陶瓷在 600 °C 下的最大烧结密度为 3.6 g/cm 3，介电常数为 7.8，品质因数 (Q × f) 为 56,800 GHz，谐振频率温度系数 (τ f ) 为 -83 ppm/°C，而 Na 5 Yb(MoO 4 ) 4 陶瓷在 570°C 下的最大烧结密度为 3.9 g/cm 3，介电常数为 6.9，品质因数 (Q × f) 为43,400 GHz，以及-68 ppm/°C 的谐振频率温度系数 (τ f )。对共烧样品的粉末 X 射线衍射和能量色散 X 射线光谱分析证实了与铝电极对 Na 5 Yb(MoO 4 ) 4 陶瓷具有良好的化学相容性，因此是 ULTCC 应用的合适候选材料。