Change of coercivity of magnetic thin films with non-magnetic layers and applications to spin valve

Co and NiFe thin films were deposited on various buffer layers such as Ta, Cu and Cr to study dependence of coercivity on the buffer layers. It has been found that coercivity of the magnetic layers could be favorably reduced when grown on Ta buffer layer. In contrast, the coercivity was enhanced for the films with Cr buffer layer. X-ray diffraction and small-angle reflection analysis revealed that the change of coercivity with various buffer layers was closely linked with structure of the magnetic films. In addition, magnetoresistance of the sandwiches with the structure of Co/NM/NiFe on different non-magnetic buffer layers has been investigated. The result indicated that spin valve effect for the sandwiches without exchange-biased field can be obtained by selecting appropriate non-magnetic layer.