The low loss and small density of lithium-based microwave dielectric ceramics (MWDCs) make them promising for communication devices such as dielectric filters, antennas, and substrates. In this study, (1-x)[Li₂Ti_0.98Mg_0.02O_2.96F_0.04−1 wt%Nb₂O₅]-xLi₃Mg₂NbO₆ (LTMN_0.02-LMN, 0 ≤ x ≤ 0.1) MWDCs fabricated via solid solution reaction were successfully synthesized to obtain a near-zero temperature coefficient of the resonant frequency (τ_f). The X-ray diffraction pattern and Rietveld refinement results showed that a good solid solution was formed and that the phase composition of the LTMN_0.02 system gradually changed from monoclinic to cubic. Scanning electron microscopy images revealed that the microstructure of LTMN_0.02 improved as the LMN content increased. Ultimately, desirable dielectric properties were obtained by sintering at 1220 °C with x = 0.08: ε_r ∼18.1, Q × f ∼105,661 GHz, and τ_f ∼ + 1.3 ppm/°C. Furthermore, the highest Q × f value (∼131,157 GHz) was achieved in the x = 0.04 composition with relatively homogeneous grains. The high-performance LTMN_0.02-LMN ceramics developed in this study provide a new alternative material for the dielectric components of communication systems.

锂基微波介电陶瓷 (MWDC) 的低损耗和小密度使其有望用于介质滤波器、天线和基板等通信设备。在本研究中，(1- x )[Li ₂ Ti _0.98 Mg _0.02 O _2.96 F _0.04 -1 wt%Nb ₂ O ₅ ]- x Li ₃ Mg ₂ NbO ₆ (LTMN _0.02 -LMN, 0 ≤  x  ≤ 0.1) MWDCs成功合成了通过固溶反应制造的谐振频率（_τf）的接近零的温度系数）。X射线衍射图和Rietveld精修结果表明形成了良好的固溶体，LTMN _0.02体系的相组成逐渐从单斜变为立方。扫描电子显微镜图像显示，随着 LMN 含量的增加，LTMN _0.02的微观结构得到改善。最终，通过在 1220 °C 下烧结获得了理想的介电性能，x  = 0.08：ε _r ∼18.1，Q ×  f ∼105,661 GHz，τ _f ∼ + 1.3 ppm/℃。此外，最高的Q×  ˚F值（~131,157千兆赫）在达到X = 0.04 组成，具有相对均匀的晶粒。本研究开发的高性能 LTMN _0.02 -LMN 陶瓷为通信系统的介电元件提供了一种新的替代材料。