SOFT MAGNETIC-PROPERTIES OF CO-FE-P AND CO-FE-SN-P AMORPHOUS FILMS FORMED BY ELECTROPLATING

Co-Fe-P and Co-Fe-Sn-P amorphous alloys are formed by electroplating. These alloys have zero magnetostrictive compositions, and show high saturation magnetic induction Bs of 10-13.5 kG and high permeability 3000–5000 at 5 MHz with 2 µm thickness. It is found that the addition of Sn to Co-Fe-P improves the corrosion resistance without decreasing saturation magnetic induction. The magnetic domain structures of the thin film head shaped cores with Co-Fe-P amorphous films were also observed by the magneto-optical longitudinal Kerr effect technique. The direction of magnetization oriented along the track width in the negative magnetostrictive film. © 1990 IEEE