Dependence of magnetoresistance on thickness and substrate temperature for 82Ni-Fe alloy film

The dependence of magnetoresistance on film thickness and substrate temperature has been studied on 82Ni-Fe alloy films. The anisotropic resistivity Δρ{variant} = ρ{variant} - ρ{variant}_⊥ is nearly a constant of about 0.64 μΩcm when the thickness of the films is 200 to 1400 Å. An anisotropic magnetoresistivity ratio (Δρ{variant}/ρ{variant}₀) of 2.5 to 3% is obtained in the 1000 to 1200 Å thick films prepared at the substrate temperature of 350 °C. The corresponding magnetic properties are H_c = 2 to 2.5 Oe, H_c⊥ = 0.5 to 0.6 Oe, and H_k = 4 Oe. The resistivity decreases with increasing of the film thickness or substrate temperature. The decrease of resistivity ρ{variant}₀ can be understood by considering the decrease of diffused scattering at the film surface or grain boundary. The asymmetry of the Δρ{variant}/ρ{variant}₀ vs. H curve is also discussed.