Magnetic and galvanomagnetic properties of amorphous CoZr thin films

Magnetic and galvanomagnetic properties of Co94Zr6 amorhous films were studied over a thickness range from ∼100 Å to 3 μm. The values of magnetization and magnetostriction were 14.5 kG and <10−6, respectively, independent of thickness. The coercivity Hc, however, was a strong function of thickness and follows the Néel predictions for wall motion coercivity mechanism. The induced anisotropy was uniaxial and decreased with film thickness. This change is not understood, since the anisotropy is believed to be due to pair ordering, which should be independent of thickness. The anisotropy dispersion angle α90 and, therefore, the ripple parameter S, were found to be very small for samples thicker than 5000 Å. The resistivity of the films increased as the thickness decreased and could be described over the entire thickness range by a ‘‘bulk resistivity’’ of ρ0=80 μΩ cm and a mean free path of the conductive electrons of l0=33 Å.