Ku band microwave studies of fritless strontium hexaferrite thick films

Abstract

PurposeThe aim of this paper is to investigate microwave Ku band absorbance, complex permittivity, and permeability of SrFe12O19 thick films by a simple and novel waveguide technique.Design/methodology/approachThe glass frit free or fritless strontium hexaferrite thick films were formulated on alumina by screen printing technique from the powder synthesized by chemical co precipitation method for pH 11 adjusted during the reaction. The 13‐18 GHz frequency band microwave absorbance of the SrFe12O19 thick films by a simple waveguide method. The complex permittivity and permeability of strontium hexaferrite thick films was measured by voltage standing wave ratio technique.FindingsSrFe12O19 thick films show high ∼80 percent absorbance in the whole 13‐18 GHz frequency band. The thickness dependant microwave properties of strontium hexaferrite thick films were observed. The real permittivity ε′ lies in between eight and 35 with the variation in thickness of the thick film SrFe12O19. The real microwave permeability μ′ of strontium hexaferrite thick films lies in the range 1.12‐6.41. The resonance type behavior was observed at frequency 14.3 GHz. The SrFe12O19 thick film of thickness 30 μm could be a wide band (∼5,000 MHz) absorber with absorbance ∼87 percent for the whole 13‐18 GHz frequency band.Originality/valueThe complex permeability of strontium hexaferrite thick films was measured by simple novel waveguide method. The high absorbance (∼87 percent) of thick film SrFe12O19 over a broad band ∼5,000 MHz will be useful in achieving RAM coatings required for 13‐18 GHz frequency band.