Novel low loss, low permittivity (1 − x)SiO2 − xTiO2 + ywt% H3BO3 microwave dielectric ceramics for LTCC applications
Novel low loss, low permittivity (1 − x)SiO2 − xTiO2 + ywt% H3BO3 microwave dielectric ceramics for LTCC applications
复制标题
DOI：
10.1016/j.jallcom.2017.04.079
复制
发表时间：
2017-07
影响因子：
6.2
通讯作者：
Chengxi Hu;Yuan Liu;Peng Liu;Bo Yang
中科院分区：
文献类型：
--
作者：
Chengxi Hu;Yuan Liu;Peng Liu;Bo Yang
研究了用于低温共烧陶瓷的新型微波介质材料(1−(X)SiO_2)−_xTiO_2。采用溶胶凝胶法在溶剂热条件下制备了包覆了二氧化钛的二氧化钛粉末，结果表明，二氧化钛微粒在二氧化硅表面有较好的吸附。二氧化钛包覆二氧化硅改善了二氧化硅陶瓷的微波性能。在(1−x)SiO_2-−_xTiO_2(0.1-≦_x-≦_(0.3))体系中，随着TiO_2含量x的增加，材料的介电常数(ε_r)和共振频率温度系数(τƒ)都因TiO_2相的混合作用而增大。在1200℃下烧结的0.85SiO_2-0.15TiO_2和0.9SiO_2-0.1TiO_2陶瓷的εr分别为55.4和4.6，品质因数(Q·ƒ)分别为0.40,500和36,300 GHz，τƒ为0.5ppm/°C，−为0.5ppm/°C。添加H3BO_3使0.9SiO_2−_(0.1)TiO_2陶瓷的烧结温度从1200℃/3h降至950℃/6h。添加10wt%H3BO3的0.9SiO_2−/0.1TiO_2陶瓷在950℃/6℃下烧结，具有优异的微波介电性能，εr∼为4.67，q·ƒ∼为78,000 GHz，τƒ∼为0.7ppm/°C。从共烧陶瓷的X射线衍射和能谱分析可知，添加0.9SiO_2的SiO_2陶瓷在950℃时不与Ag发生反应，具有低介电常数、低烧结温度、高性能的微波介电性能、与银金属电极的化学兼容性、无毒、原料来源丰富和成本低等优点，使SiO_2陶瓷成为潜在的衬底和低温陶瓷材料。
Novel microwave dielectric material of (1 − x)SiO2− xTiO2for low-temperature cofired ceramic (LTCC) application was investigated in this paper. TiO2coated SiO2powder prepared by a sol-gel method under solvothermal conditions (SGS) revealed an adsorption of fine TiO2particles on the SiO2surface. TiO2coated SiO2improved the microwave properties of SiO2ceramics. As the TiO2content x increased in the (1 −x)SiO2−xTiO2(0.1 ≦x≦0.3) system, dielectric constant (εr) and temperature coefficient of resonance frequency (τƒ) of the material were increased due to the mixing effect of TiO2phase. The 0.85SiO2− 0.15TiO2and 0.9SiO2− 0.1TiO2ceramics sintered at 1200 °C showedεr= 5.4 and 4.6, quality factor (Q·ƒ) = 40,500 and 36,300 GHz, andτƒ= 2.5 and −0.5 ppm/°C. The sintering temperature of 0.9SiO2− 0.1TiO2ceramic is lowered from 1200 °C/3 h to 950°C/6 h by the addition of H3BO3. 0.9SiO2− 0.1TiO2ceramics with 10 wt% H3BO3sintered at 950 °C/6 h possesses excellent microwave dielectric properties ofεr∼ 4.67,Q·ƒ∼ 78,000 GHz andτƒ∼ −0.7 ppm/°C. From the X-ray diffraction and EDS analysis of cofired ceramics, the H3BO3added 0.9SiO2− 0.1TiO2ceramic does not react with Ag at 950 °C. The attractive advantages such as low dielectric constant, low sintering temperature, high-performing microwave dielectric properties, chemical compatibility with Ag metal electrodes, no toxicity, and abundant raw materials source and low cost constituents make the SiO2ceramic as potential candidates for substrate and LTCC devices.