A novel low-firing microwave dielectric ceramic Li2ZnGe3O8 with cubic spinel structure. Issue 2 (February 2017)

• Record Type: Journal Article
• Authors: Xiang, Huaicheng; Fang, Liang; Fang, Weishuang; Tang, Ying; Li, Chunchun
• Is Part Of: Journal of the European Ceramic Society. Volume 37:Issue 2(2017)
• Page Start: 625
• Page End: 629
• Publication Date: 2017-02
• Subjects: Microwave dielectric properties -- LTCC -- Spinel structure -- Li2ZnGe3O8; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2016.09.013
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: A Li2 ZnGe3 O8 ceramic was investigated as a promising microwave dielectric material for low-temperature co-fired ceramics applications. Li2 ZnGe3 O8 ceramic was prepared via the conventional solid-state method. X-ray diffraction data shows that Li2 ZnGe3 O8 ceramic crystallized into a cubic spinel structure with a space group of P 41 32. Dense ceramic with a relative densities of 96.3% were obtained when sintered at 945 °C for 4 h and exhibited the optimum microwave properties with a relative permittivity ( εr ) of 10.3, a quality factor ( Q × f ) of 47, 400 GHz (at 13.3 GHz), and a temperature coefficient of resonance frequency ( τf ) of −63.9 ppm/°C. The large negative τf of Li2 ZnGe3 O8 ceramic could be compensated by rutile TiO2, and 0.9Li2 ZnGe3 O8 –0.1TiO2 0·1TiO2 ceramic sintered at 950 °C for 4 h exhibited improved microwave dielectric properties with a near-zero τf of −1.6 ppm/°C along with εr of 11.3 and a Q × f of 35, 800 GHz (11.6 GHz). Moreover, Li2 ZnGe3 O8 was found to be chemically compatible with silver electrode when sintered at 945 °C.