High-Q Microwave Dielectrics in the (Mg1-xCox)2TiO4 Ceramics
High-Q Microwave Dielectrics in the (Mg1-xCox)2TiO4 Ceramics
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DOI：
10.1111/j.1551-2916.2008.02742.x
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发表时间：
2009-02-01
影响因子：
3.9
通讯作者：
Chen, Jhih-Yong
中科院分区：
文献类型：
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作者：
Huang, Cheng-Liang;Chen, Jhih-Yong
研究了传统固态法制备的（Mg1-xCox）(2)TiO4陶瓷的微波介电性能和显微结构。通过x射线衍射图、x射线能量色散分析和测量的晶格参数，证实了固溶体（Mg1-xCox）(2)TiO4 （x=0.02-0.1）的形成。通过将x从0增加到0.05，试样的qxf可以从15万GHz大幅提高到最大286万GHz。（Mg0.95Co0.05）(2)TiO4陶瓷在1390℃下烧结4小时，获得了微波介电性能的良好组合(epsilon（r)接近15.7，Q x f接近28.6万GHz， tau(f)接近52.5 ppm/℃）。钛铁矿结构（Mg0.95Co0.05）TiO3作为第二相被检测到。第二相的存在不会引起试样介电性能的显著变化，因为它与主相相比具有相容性。此外，在1360°c -1420°c下，x=0.04-0.05的样品在介电性能上只有很小的偏差。它不仅提供了一个宽的处理窗口，而且确保了一种非常可靠的材料，作为低损耗微波和毫米波应用的非常有前途的介电材料。
The microwave dielectric properties and the microstructures of (Mg1-xCox)(2)TiO4 ceramics prepared by the conventional solid-state route were investigated. Lattice parameters were also measured for specimens with different x. The formation of solid solution (Mg1-xCox)(2)TiO4 (x=0.02-0.1) was confirmed by the X-ray diffraction patterns, energy dispersive X-ray analysis, and the lattice parameters measured. By increasing x from 0 to 0.05, the Q x f of the specimen can be tremendously boosted from 150 000 GHz to a maximum of 286 000 GHz. A fine combination of microwave dielectric properties (epsilon(r)similar to 15.7, Q x f similar to 286 000 GHz at 10.4 GHz, tau(f)similar to-52.5 ppm/degrees C) was achieved for (Mg0.95Co0.05)(2)TiO4 ceramics sintered at 1390 degrees C for 4 h. Ilmenite-structured (Mg0.95Co0.05)TiO3 was detected as a second phase. The presence of the second phase would cause no significant variation in the dielectric properties of the specimen because it possesses compatible properties compared with that of the main phase. In addition, only a small deviation in the dielectric properties was monitored for specimens with x=0.04-0.05 at 1360 degrees-1420 degrees C. It not only provides a wide process window but also ensures an extremely reliable material proposed as a very promising dielectric for low-loss microwave and millimeter wave applications.