Near-zero temperature coefficient in Mg^(2+)-Ti^(4+) co-doped Sm_(2)O_(3)-CaSmAlO_(4) microwave dielectric ceramics  

作　　者：Jin-Quan Zeng Jun-Lei Qi Yue-Yang Yang Min-Hao Zhang Yuan-Hua Lin 

机构地区：[1]State Key Laboratory of New Ceramics and Fine Processing,School of Materials Science and Engineering,Tsinghua University,Beijing,100800,China [2]Innovation Team for New High Volumetric Efficient MLCC Materials and Devices,Foshan(Southern China)Institute for New Materials,Foshan,528200,China

出　　处：《Rare Metals》2024年第12期6549-6558,共10页稀有金属(英文版)

基　　金：financially supported by the National Key Research Program of China (No.2021YFB3800601);the Basic Science Center Project of the National Natural Science Foundation of China (No.52388201);the Fellowship of China Postdoctoral Science Foundation (No.2022M710073)。

摘　　要：The practical application of CaSmAlO_(4)microwave dielectric ceramics is limited by its low quality factor(Q×f)value and non-zero temperature coefficient resonant frequency(τ_(f))value.In this study,we introduced Mg^(2+)-Ti^(4+)ionic pairs into CaSmAlO_(4),along with an excess of 9%Sm_(2)O_(3).The Mg^(2+)-Ti^(4+)ionic pairs substituted Al^(3+),and two phases simultaneously coexisted in the ceramics:CaSmAlO_(4) and Sm_(2)O_(3).As the doping concentration of Mg^(2+)-Ti^(4+)ionic pairs increased,the relative permittivity exhibited an upward trend,while the quality factor and resonant frequency temperature coefficient first rose and then descended.Remarkably,0.09Sm_(2)O_(3)-0.91CaSmAl_(0.7)Mg_(0.15)-Ti_(0.15)O_(4) sintered at 1450℃ yielded excellent dielectric properties:ε_(r)=19.72,Q×f=72,936 GHz,and τ_(f)=-0.044 ppm·℃^(-1).The factors influencing the microwave dielectric properties of 0.09Sm_(2)O_(3)-0.91CaSmAlO_(4)ceramics were further examined by considering the crystal structure,grain size,Lichtenecker logarithmic rule,tolerance factor and packing fraction.

关 键 词：CaSmAlO_(4) Near-zero temperature coefficient Microwave dielectric ceramics 

分 类 号：TQ1[化学工程]