@article{Liu2025, 
author = {Yanjun Liu and Guoqiang He and Wenjie Zhang and Yuan Nie and Fangyi Huang and Huanfu Zhou},
title = {Low loss and temperature-stable Y3MgAl3GeO12 microwave dielectric ceramics for X-band applications},
year = {2025},
journal = {Journal of Advanced Ceramics},
volume = {14},
number = {9},
pages = {9221136},
keywords = {microwave dielectric ceramics (MWDCs), dielectric resonator antenna, terahertz spectroscopy, far-infrared spectroscopy, 5G/6G communication},
url = {https://www.sciopen.com/article/10.26599/JAC.2025.9221136},
doi = {10.26599/JAC.2025.9221136},
abstract = {With the rapid deployment of 5G and the emergence of 6G technologies, the demand for high-performance microwave dielectric ceramics (MWDCs) has increased. This study developed Y3MgAl3GeO12 (YMAG) garnet ceramics to meet 5G/6G requirements for low signal delay, low loss, and high-temperature stability. YMAG ceramics synthesized via a solid-state reaction were characterized for phase composition, crystal structure, microstructure, and microwave dielectric properties. The results revealed that YMAG ceramics exhibited excellent microwave performance: a permittivity (εr) of 9.86, a quality factor (Q×f) of 89,000 GHz, and a temperature coefficient of resonant frequency (τf) of −40 ppm/°C. Far-infrared and terahertz (THz) spectroscopic analyses verified the low intrinsic dielectric loss and frequency-stable dielectric characteristics of the material in high-frequency ranges. Temperature-dependent dielectric measurements coupled with thermal expansion studies revealed outstanding stability in this material, as evidenced by its low coefficient of thermal expansion (αL = 9.13 ppm/°C). To attain near-zero τf, we added TiO2 as a positive τf compensation agent. This strategy effectively tuned the τf value to within |τf| < 10 ppm/°C while preserving excellent microwave dielectric performance (Q×f ≈ 43,000 GHz). Furthermore, a rectangular dielectric resonator antenna (DRA) designed with the optimized YMAG–TiO2 composite demonstrated excellent impedance matching (VSWR = 1.02) and high radiation efficiency (> 90%) in the X-band (10.21 GHz), validating its potential for 5G/6G applications. This work provides a novel approach for developing high-performance MWDCs for next-generation communication technologies and emphasizes the critical role of material design and optimization in achieving superior microwave properties.}
}