The effect of growth surface morphology on the crystal structure and magnetic property of L10 order PtFe layers deposited by magnetron sputtering

The Fe/Pt/Fe/Pt layers (Pt/Fe multilayer) were deposited on general glass substrate at room temperature by magnetron sputtering technique. Varying the deposition and post-annealing treatment parameters, the PtFe alloy (PtFe) layer with different crystal structures and magnetic properties were obtained at the interface between Fe and Pt layer. The characterization by X-ray diffraction (XRD) showed that the as-deposited Pt/Fe multilayer only contained pure Fe and Pt with body-centered and face-centered cubic structures, respectively. As-deposited Pt layer displayed (2 0 0) preferred orientation, and the columnar grains structure could be observed by the scanning electron microscopy. The PtFe layers with L10 face-centered cubic structure could be formed at the interface between Pt and Fe layers by post-annealing the multilayers at 500 °C. In case of Pt/Fe multilayer deposited on smooth substrate, the larger columnar grains in Pt layer resulted in L10 PtFe layers without any preferred orientation. While in case of Pt/Fe multilayer deposited on the rough substrate, the thinner columnar grains in Pt layer could induce L10 PtFe layers with (2 0 0) preferred orientation. In this case, the vibrating sample magnetometer results indicated that, the magnetic coercivity in plane and out-of-plane model could reach 3.72 and 2.32 kOe, respectively. Based on above results, the L10 structure Pt/Fe multilayer with satisfied magnetic properties could be prepared at low temperature by our simple route.