Influence of Cu insertion layer on magnetic property of [Co(0.3 nm)/Ni(0.6 nm)]10/Cu/[Co(0.3 nm)/Ni(0.6 nm)]10 spin valve thin films

In this work, series of thin films of [Co(0.3 nm)/Ni(0.6 nm)](10)/Cu(t nm)/[Co(0.3 nm)/Ni(0.6 nm)](10) (with t = 0, 2, 4, 6 nm) multilayers have been prepared on Si substrate to study the influence of Cu insertion layer on magnetic property. The as-prepared [Co(0.3 nm)/Ni(0.6 nm)](20) as well as films with Cu insertion layer exhibit perpendicular magnetic anisotropic (PMA) behavior. The values of coercivity are found to enhance with the increase in the thickness of the Cu insertion layer. The strength of PMA, critically depends on the thickness of the Cu insertion layer. The value of the effective PMA constant is found to decrease and it is estimated to be 9.5 x 10(5), 6.6 x 10(5), 2.2 x 10(5), 0.4 x 10(5) erg/cm(3) for films with Cu insertion layers of 0, 2, 4, and 6 nm respectively. The observed PMA is explained in a correlation with surface topography and roughness studied by 3D optical profilometer images.