Synthesis and Microwave Dielectric Properties of MgSiO₃ Ceramics

Abstract

MgSiO 3 ceramics were synthesized and their microwave dielectric properties were investigated. The Mg 2 SiO 4 phase was formed at temperatures lower than 12001C, while the orthorhombic MgSiO 3 phase started to form by the reaction of SiO 2 and Mg 2 SiO 4 in the specimen fired at 12001C. The structure of the MgSiO 3 ceramics was transformed from orthorhombic to monoclinic when the sintering temperature exceeded 14001C. A dense microstructure was developed for the specimens sintered at above 13501C. The excellent microwave dielectric properties of e r 5 6.7, Q Â f 5 121 200 GHz, and s f 5 À17 ppm/1C were obtained from the MgSiO 3 ceramics sintered at 13801C for 13 h.X. M. Chen-contributing editor

Synthesis of (1−x)ZnAl2O4–xTiO2 microwave dielectric ceramics by molten-salt process

“…For application to millimeter-wave systems, microwave dielectric materials require a low dielectric constant (ε r ) to minimize the cross-coupling effect with conductors and shorten the time for the electronic signal transition, a high quality factor (Q·f) to increase their selectivity, and a near-zero temperature coefficient of resonant frequency ( f ) to ensure the stability of the frequency against temperature changes [1].…”

Structural evolution, low-firing characteristic and microwave dielectric properties of magnesium and sodium vanadate ceramic

“…The aluminate and silicate compounds demonstrate good microwave dielectric properties with low relative dielectric constant (ε r ) and high quality factor (Q×f). However, they show large τ f values and particularly high sintering temperatures (1300~1550 o C) [5,6,8]. The vanadate compounds present low sintering temperatures, appropriate ε r and high Q×f values, such as Mg 3 (VO 4 ) 2 [32] and Mg 2 V 2 O 7 [33], but large τ f values restrict their further application.…”

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A novel low-firing microwave dielectric ceramic NaMg4V3O12 and its chemical compatibility with silver electrode

“…The advanced substrate materials for microwave integrated circuits should have a low relative permittivity (ε r ) to reduce the signal propagation delay, a high quality factor (Q u ×f) for frequency selectivity, and a near-zero temperature coefficient of resonant frequency (τ f ) for temperature stability [3]. A great number of low loss microwave dielectric ceramics with low ε r and high Q u ×f, such as MgSiO 3 [4], Mg 4 Nb 2 O 9 [5], Yb 2 BaCu 0.5 Zn 0.5 O 5 [6], have been developed. However, their high sintering temperatures (>1200 o C) limit their practical application in LTCC technology.…”