A Novel Low‐Firing and Low Loss Microwave Dielectric Ceramic Li2Mg2W2O9 with Corundum Structure. Issue 12 (26th August 2015)

• Record Type: Journal Article
• Authors: Guo, Huanhuan; Fang, Liang; Jiang, Xuewen; Li, Jie; Lu, Fengqi; Li, Chunchun
• Is Part Of: Journal of the American Ceramic Society. Volume 98:Issue 12(2015)
• Page Start: 3863
• Page End: 3868
• Publication Date: 2015-08-26
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.13829
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract : The crystal structure and microwave dielectric properties of a novel low‐firing compound Li2 Mg2 W2 O9 were investigated in this study. The phase purity and crystal structure were investigated using X‐ray diffraction analyses and Rietveld refinement. The best microwave dielectric properties of the ceramic with a low permittivity (εr ) ~11.5, a quality factor ( Q × f) ~31 900 GHz (at 10.76 GHz) and a temperature coefficient of the resonant frequency (τf ) ~ −66.0 ppm/°C were obtained at the optimum sintering temperature (920°C). CaTiO3 was added into the Li2 Mg2 W2 O9 ceramic to obtain a near zero τf, and 0.93Li2 Mg2 W2 O9 –0.07CaTiO3 ceramic exhibited improved microwave dielectric properties with a near‐zero τ f ~ −1.3 ppm/°C, a εr ~ 21.6, a high Q u × f value ~20 657 GHz. The low sintering temperature and favorable microwave dielectric properties make it a promising candidate for LTCC applications.