Synthesis, sintering behavior and magnetic properties of Cu-substituted Co2Z hexagonal ferrites

• Published in: Journal of materials science. Materials in electronics 2011-05, Vol.22 (5), p.467-473
• Main Authors: KRACUNOVSKA, S, TÖPFER, J
• Format: Article
• Language: English
• Subjects: Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Copper; Electronics; Exact sciences and technology; Ferrites; Inductors; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Magnetic devices; Magnetic properties; Magnetic properties and materials; Magnetic properties of nanostructures; Materials; Materials Science; Optical and Electronic Materials; Permeability; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sintering; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-010-0161-4

Cu-substituted Z-type Ba 3 Co 2− x Cu x Fe 24 O 41 hexagonal ferrites (0 ≤  x  ≤ 1) were prepared by the standard oxide route. Almost single phase Z-type ferrite powders were observed after calcination at 1,260 °C. The permeability of samples sintered at 1,260 °C varies with the Cu content; a maximum permeability at 10 MHz of μ′ = 17 was found for x  = 0.6. It is shown that the permeability behavior is determined by the concentration of Z-type ferrite in the sample and the microstructure. Addition of 3 wt% Bi 2 O 3 leads to almost complete densification of Co 2 Z samples under low temperature ceramic cofiring (LTCC) conditions at 900 °C. However, the permeability of samples sintered at 900 °C is reduced to μ′ = 5 with resonance frequency at 2 GHz. It is shown that Cu-substituted Co 2 Z ferrites are not stable at T