Chou Chen-Chia, Chang Chun-Yao, Chen Guang-Yu, Liao Wen-Jiao, Feng Kuei-Chih, Tsao Chung-Ya
Department of Mechanical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Road, Sec. 4, Taipei 10607, Taiwan.
Department of Electrical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Road, Sec. 4, Taipei 10607, Taiwan.
Materials (Basel). 2017 Dec 29;11(1):55. doi: 10.3390/ma11010055.
Electrode material for low-temperature co-fired diopside glass-ceramic used for microwave dielectrics was investigated in the present work. Diffusion of silver from the electrode to diopside glass-ceramics degrades the performance of the microwave dielectrics. Two approaches were adopted to resolve the problem of silver diffusion. Firstly, silicon-oxide (SiO₂) powder was employed and secondly crystalline phases were chosen to modify the sintering behavior and inhibit silver ions diffusion. Nanoscale amorphous SiO₂ powder turns to the quartz phase uniformly in dielectric material during the sintering process, and prevents the silver from diffusion. The chosen crystalline phase mixing into the glass-ceramics enhances crystallinity of the material and inhibits silver diffusion as well. The result provides a method to decrease the diffusivity of silver ions by adding the appropriate amount of SiO₂ and appropriate crystalline ceramics in diopside glass-ceramic dielectric materials. Finally, we used IEEE 802.11a 5.8 GHz as target specification to manufacture LTCC antenna and the results show that a good broadband antenna was made using CaMgSi₂O₆ with 4 wt % silicon oxide.
本文研究了用于微波介质的低温共烧透辉石微晶玻璃的电极材料。银从电极向透辉石微晶玻璃的扩散会降低微波介质的性能。采用了两种方法来解决银扩散问题。首先，使用了氧化硅（SiO₂）粉末，其次选择晶相来改变烧结行为并抑制银离子扩散。纳米级非晶态SiO₂粉末在烧结过程中在介电材料中均匀转变为石英相，并防止银扩散。所选的晶相混入微晶玻璃中可提高材料的结晶度并抑制银扩散。该结果提供了一种通过在透辉石微晶玻璃介电材料中添加适量的SiO₂和合适的晶态陶瓷来降低银离子扩散率的方法。最后，我们以IEEE 802.11a 5.8 GHz作为目标规格来制造LTCC天线，结果表明使用含有4 wt%氧化硅的CaMgSi₂O₆制成了良好的宽带天线。
