Low loss microwave ferroelectric ceramics for high power tunable devices

• Published in: Journal of the European Ceramic Society Vol. 30; no. 2; pp. 395 - 400
• Main Authors: Nenasheva, E.A., Kartenko, N.F., Gaidamaka, I.M., Trubitsyna, O.N., Redozubov, S.S., Dedyk, A.I., Kanareykin, A.D.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2010
• Subjects: (A) Sintering; (B) Microstructure; (C) Dielectric properties; (D) BaTiO 3 and titanates; Electron microscopy; MgO; (C) Dielectric properties; (D) BaTiO 3 and titanates; (B) Microstructure; (A) Sintering; MgO; Electron microscopy
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2009.04.008

In this paper we report the influence of the composition and concentration of Mg-containing additions such as Mg 2TiO 4, MgO and a mixture of Mg 2TiO 4–MgO on ceramics based on a mixture of BaTiO 3/SrTiO 3. Phase relations, crystal structure, microstructures, microwave dielectric properties ( ɛ, tan δ) and DC tunability have been studied over a wide range of frequencies. The temperature dependence of the dielectric properties has been measured as well. Among the compositions synthesized were low loss bulk ferroelectrics with dielectric constants in the range 150–800 and relatively high DC tunabilities (up to 1.49 under a DC electric field of 40 kV/cm). These materials can be used for high power tunable microwave devices.