Fe-Si-Cr/PTFE Magnetic Composite Thick Films on Polyethylene Terephthalate Sheets for Near Field Communications by Aerosol Deposition

Abstract

Thick film growth of Fe-Si-Cr/poly-tetra-fluoro-ethylene (PTFE) composite films on polyethylene terephthalate (PET) sheets was investigated by aerosol deposition (AD) as a magnetic absorber for near field communication. The Fe-Si-Cr flakes were crushed to micro flakes smaller than 1 mu m after the deposition, and formed dense microstructure on the PET sheets. The Fe-Si-Cr/PTFE composite thick films using 0.2 wt.% PTFE starting powder showed dense and uniform microstructure compared to the 0.5 wt.% film. The real relative permeability mu' and the imaginary permeability mu '' of Fe-Si-Cr/PTFE composite thick films using the 0.2 wt.% PTFE starting powder were 13.1 and 2.9 at 13.56 MHz, respectively. In the case of 0.5 wt.%, mu' and mu '' respectively decreased to 7.4 and 1.0 at 13.56 MHz caused by adding PTFE.