Investigation On Anisotropic Magnetoresistance Of Ni₇₄Co₂₆Thin Films

The Ni74Co26 films were prepared by using DC magnetron sputtering, the structural and magnetic properties were studied systematically in thesis.The major results obtained are summarized as follows.(1) ( Ni81Fe19)66Cr34(xnm)/ Ni74Co26(20nm) film have been prepared and the effect of (Ni81Fe19 ) 66Cr34 buffer layer thickness on the properties of the films has been studied.The results show that the AMR value of the film reaches a maximum value at x=5nm,then decreases with x increases, at x>9nm,the value decreases rapidly.( 2 ) The AMR value of the Ni74Co26 deposited on 5nm (Ni81Fe19)66Cr34 buffer layer is higher than that of the films deposited on 5nm Ta buffer layer .For example, the AMR value of the 10nm Ni74Co26 deposited on (Ni81Fe19)66Cr34 buffer layer is 2.6%, the AMR value of the Ni74Co26 deposited on Ta buffer layer is 1.6%.(3) Samples were annealed under different TA CTa=200℃, 300℃, 400℃),the result indicates that the value of AMR reachs its maximum at 200℃, approximately enhance 30%,then the value decrease dramatically when the temperature exceed 200℃.(4) Texture of Ni74Co26 films were improved no matter which temperature after annealed, however the AMR value decrease dramatically when the temperature exceed 200℃,less than deposit film AMR value. The interdiffusion increases with T,resulting in lower Ms and higher Hc.