Magnetic and Structural Characterization of NiFe/Fe₃₀Co₇₀ Bilayers

摘要

Magnetostrictive films are required for a wide range of device applications; by increasing the magnetostriction constant and decreasing the anisotropy field, the devices will become more efficient. This paper has studied FeCo films on different thicknesses of the soft magnetic underlayer NiFe, to determine how the structural and magnetic properties change. It was found that the anisotropy field of the FeCo film could be reduced by 50% to 10 kA/m and the magnetostriction constant increased by a factor 4 to 65 ppm when grown on 30 nm NiFe. This was due to the NiFe underlayer inducing a BCC(110) texture within the FeCo film and reducing the in-plane stress.