FePt (001) texture development on an Fe–Ta–C magnetic soft underlayer with SiO2/MgO as an intermediate layer

In order to develop the FePt (001) texture on an Fe–Ta–C magnetic soft underlayer (SUL), a combined ${\mathrm{SiO}}_2/\mathrm{MgO}$ intermediate layer is used between the SUL and FePt/MgO laminated recording layer. The function of the amorphous ${\mathrm{SiO}}_2$ layer is to cut the epitaxial growth relationship between the SUL and recording layer and to establish the MgO (200) texture. The thin FePt layers are epitaxially grown on the MgO layers and transformed into (001)-textured ${\text{L1}}_0$ FePt films upon annealing. Increasing the surface roughness of the Fe–Ta–C SUL from 0.74 to 2.35 nm does not significantly affect the FePt (001) texture, but has an effect on the FePt grain $c$ -axis dispersion and the FePt ${\text{L1}}_0$ phase ordering.