Effects of Third Elements on the Surface and Volume Perpendicular Coercivity of Co-Cr Films

The effects of third additive elements on the surface and volume perpendicular magnetic coercivity of Co-Cr alloy films were studied. The difference of surface and volume coercivities between the coercivity thickness dependences in Co-Cr-Ta and Nb films is discussed. It is clearly shown that the Co-Cr-Nb film shows almost the same tendency in the thickness dependence of both surface and volume coercivity. It is concluded that Co-Cr-Nb films are superior to Co-Cr-Ta in term of magnetic coupling in the film thickness direction, exhibiting a high crystallinity and a high crystal orientation.