Dielectric properties of Ga2O3-doped barium iron niobate ceramics

• Main Authors: Sanjoom,K., Pengpat,K., Eitssayeam,S., Tunkasiri,T., Rujijanagul,G.
• Format: Conference or Workshop Item
• Published: Wiley-VCH Verlag 2015
• Subjects: Surfaces, Coatings and Films; Surfaces and Interfaces; Materials Chemistry; Electrical and Electronic Engineering; Electronic, Optical and Magnetic Materials; Condensed Matter Physics
• Online Access: http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=84905986170&origin=inward; http://cmuir.cmu.ac.th/handle/6653943832/38757
• Institution: Chiang Mai University

Ga-doped BaFe0.5Nb0.5O3 (Ba(Fe 1-xGax)0.5Nb0.5O3) ceramics were fabricated and their properties were investigated. All ceramics showed perovskite structure with cubic symmetry and the solubility of Ga in BFN ceramics had a limit at x = 0.2. Examination of the dielectric spectra indicated that all ceramic samples presented high dielectric constants that were frequency dependent. The x = 0.2 ceramic showed a very high dielectric constant (εr > 240 000 at 1 kHz) while the x = 0.4 sample exhibited high thermal stability of dielectric constant with low loss tangent from room temperature (RT) to 100°C with εr > 28 000 (at 1 kHz) when compared to other samples. By using a complex impedance analysis technique, bulk grain, grain boundary, and electrode response were found to affect the dielectric behavior that could be related to the Maxwell-Wagner polarization mechanism © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.