RELATIONSHIP BETWEEN MICROSTRUCTURE AND MAGNETIC-PROPERTIES IN SOFT FE-TA-N FILMS

Transverse biased permeability measurements (TBP) were utilized to obt ain experimental values of the structure factor using Hoffman's ripple theory in order to expose the relationship between microstructure and magnetic properties in de sputtered Fe-Ta-N single layer films with 5 .5 a.o.% Ta and varying nitrogen content. The grain size and orientati on of the films were obtained by X-ray diffraction and the stress was measured directly. The initial permeability increased from 600 to almo st 1700 and the wall coercivity dropped from 5.5 Oe to 1.2 Oe when the structure factor decreased front 0.12 erg/cm(2) to 0.02 erg/cm(2). Th e addition of nitrogen causes a decrease in grain diameter, which is p artially responsible for the reduction of the structure factor. The me asured structure factor was in reasonable agreement with the value cal culated from the film parameters determined experimentally using eithe r the Doyle-Finnegan model or the Takahashi-Shimatsu model for the loc al anisotropy. Differences between the models are discussed.