无机材料学报2025，Vol.40Issue(5)：536-544,9.DOI:10.15541/jim20240494
超低介电常数LiBxAl1-xSi2O6微波介质陶瓷的低温烧结
Low-temperature Sintering of LiBxAl1-xSi2O6 Microwave Dielectric Ceramics with Ultra-low Permittivity
摘要
Abstract
The lithium-based silicate microwave dielectric ceramics with ultra-low permittivity show great potential as substrate materials in the fifth-generation wireless communication technology.However,the residual stress caused by higher sintering temperatures leads to increased dielectric loss,thereby deteriorating the microwave dielectric performance.In this work,B3+was introduced into LiAlSi2O6 ceramics to reduce Al3+content,aiming to improve their sintering temperature and microwave dielectric performance.LiBxAl1-xSi2O6(0≤x≤0.20)microwave dielectric ceramics were prepared using a combination of solid-state reaction and cold isostatic pressing techniques.Effects of B3+doping on the sintering characteristics,phase structure,microstructure,and microwave dielectric properties of the materials were characterized.The results show that with a gradual increase in the doping concentration,sintering temperature of the ceramics decreases significantly from 1400 to 1000℃.Meanwhile,the relative permittivity(εr)decreases from 3.95 to 3.69,the quality factor(Q×f)increases significantly from 24300 to 30560 GHz,and the temperature coefficient of resonant frequency(τf)increases from-45.9×10-6 to-20.9×10-6℃-1.Specifically,the change in εr is mainly influenced by intrinsic polarization,lattice vibrations,and covalent bond strength of the material;the improvement in Q×f is closely related to the increase in packing fraction(PF)and the decrease in damping coefficient;the increase in τf is strongly correlated with the bond valence of oxygen(VO).Furthermore,the composition with x=0.20 exhibits the best microwave dielectric performance with εr=3.69,Q×f=30560 GHz,and τf=-20.9×10-6℃-1.Findings of this study on LiBxAl1-xSi2O6 provide important theoretical guidance and practical insights for development and application of high-performance microwave dielectric ceramics in the future.关键词
超低介电常数/硅酸铝锂/微波介电性能Key words
ultra-low permittivity/lithium aluminum silicate/microwave dielectric property分类
化学化工引用本文复制引用
熊思宇,莫尘,朱肖伟,朱国斌,陈德钦,刘来君,施晓东,李纯纯..超低介电常数LiBxAl1-xSi2O6微波介质陶瓷的低温烧结[J].无机材料学报,2025,40(5):536-544,9.基金项目
国家自然科学基金(62061011)National Natural Science Foundation of China(62061011) （62061011）
