HIGH-FREQUENCY INITIAL PERMEABILITY OF NIFE AND FEALN

The initial permeability of NiFe single layer films and single and mul ti-layer FeAlN films up to 500 MHz are presented. The permeability of thin (<1500 Angstrom) NiFe and FeAlN films were fit with calculations based on the Landau-Lifshitz/Gilbert model for phenomenological dampin g, using damping factors of similar to 0.016 and similar to 0.026, res pectively. Transverse bias permeability measurements identified larger ripple fields in FeAlN samples compared to those in thin NiFe samples . The permeability of similar to 2 mu m thick NiFe and FeAlN films wer e well described by eddy current theory. The permeability roll off fre quency of 2 mu m thick patterned FeAlN films increased from 20 to 200 MHz when laminated into 32 layers separated by 25 Angstrom thick SiN i nterlayers.