Broad band absorbance of barium hexaferrite thick films in the 8-12 GHz frequency spectrum

Abstract

Screen printed barium hexaferrite thick films on alumina with broad band absorbance in the X band were fabricated. BaFe12O19 was synthesized using a cost effective low temperature co-precipitation method with varying Fe/Ba molar ratio and pH. The thick film showed increased grain size for higher Fe/Ba molar ratio. The complex permittivity and permeability of these thick films showed wavelike behavior in a range of 9.5 GHz to 10.5 GHz. Synthesis conditions of hexaferrite powder and the dependency of the complex permittivity and the permeability of BaFe12O19 thick films on thickness in the 8 to 12 and the permeability of BaFe12O19 thick films in the 8 GHz to 12 GHz frequency spectrum are discussed in this paper. The high frequency (8 GHz to 12 GHz) reflection loss of thick film barium hexaferrite was investigated and was found to be dependent on the synthesis parameters and the thickness of the thick films. The absorption measured was more than 80% over the entire X band.