High-Q Li2Mg2(MoO4)3 dielectrics for LTCC applications at microwave frequencies

• Published in: Journal of Asian Ceramic Societies Vol. 8; no. 2; pp. 430 - 436
• Main Authors: Huang, Cheng-Liang, Tsai, Cho-Cheng, Tsai, Meng-Hung, Huang, Wen-Chiao
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 02.04.2020; Taylor & Francis Group
• Subjects: bond valence; High-Q; LTCC; microwave dielectric properties
• ISSN: 2187-0764
• DOI: 10.1080/21870764.2020.1749374

Li 2 Mg 2 (MoO 4 ) 3 dielectric was prepared via the conventional solid-state method, and its dielectric properties were investigated in the microwave frequency region. The XRD patterns of the sintered samples revealed single-phase formation with an orthorhombic structure and a space group belonging to Pnma(62). Lattice parameters, bond length, and Raman spectra of the ceramics were also investigated. The dielectric properties exhibited significant dependence on the sintering conditions. The values (resonant frequency temperature coefficient) remained in a range from - 60 to - 69 ppm/°C for all specimens because the changes in the unit cell volume were small. Excellent microwave dielectric properties (ε r ~ 9.5, Q × f ~ 80,000 GHz and τ f ~ - 69 ppm/°C) can be obtained for Li 2 Mg 2 (MoO 4 ) 3 ceramics sintered at 880°C for 4 h. This constitutes a very promising material for LTCC applications.