INFLUENCE OF THE NONMAGNETIC METAL SPACER ON THE MAGNETIC PROPERTIES AND MICROSTRUCTURE OF THE MULTILAYER FILMS

Ta/NiFe/Bi (Ag, Cu)/FeMn/Ta and Ta/NiFe1/FeMn/Bi(Ag, Cu)/NiFen/Ta films were prepared by magnetic sputtering. The texture and the dependences of the exchange-coupling field on the thickness of Bi, Ag, and Cu in Ta/NiFe/Bi(Ag, Cu)/FeMn/Ta and Ta/NiFe1/FeMn/Bi(Ag, Cu)/NiFen/Ta films were studied. XPS results indicate that the Bi atoms migrated into the FeMn layer during the deposition process and a FeMnBi alloy was probably formed or the Bi atoms existed as an impurity in the FeMn layer in Ta/NiFe/Bi(Ag, Cu)/FeMn/Ta. Otherwise, in Ta/NiFe1/FeMn/Bi(Ag, Cu)/NiFen/Ta films, Bi, Ag, and Cu atoms do not remain entirely at the interface of the FeMn/NiFen film, but at least partly segregate to the surface of the NiFe film.