INITIAL PERMEABILITY OF (111) ORIENTED FE-SI POLYCRYSTALLINE THIN-FILMS

Initial permeability (mu-i) of polycrystalline Fe-based alloy films with (111) orientation is investigated both theoretically and experimentally. It is expected from the calculation that (111) oriented films have higher mu-i than those of films with other orientations and good frequency characteristics. Fe-7-wt%-Si films with (111) orientation are expected from the calculation to have mu-i higher than 2000. Experimentally, (111) oriented Fe-6.9-wt%-Si films exhibit mu-i of about 1700 and are independent of frequencies up to 60 MHz. The results are in fairly good agreement with the calculation. The differences between the results of experiment and calculation can be explained by imperfect orientation of (111) planes and surface roughness in the actual films.