Epitaxial Co50Fe50(110)/Pt(111) films on MgAl2O4(001) and its enhancement of perpendicular magnetic anisotropy

Abstract

Perpendicular magnetic anisotropy (PMA) in magnetic thin films with low coercivity is desirable for magnetic memory devices. It has been found that a (111)-oriented or textured Pt seed layer can enhance PMA and is, therefore, commonly utilized in spintronic structures. We grow (111)-oriented Pt epitaxial films via off-axis sputtering on various substrates and investigate the optimal substrate and orientation for high quality, epitaxial growth. Our results show that Pt(111) epitaxial films grow remarkably well on MgAl2O4(001) with an exceptionally narrow X-ray diffraction rocking curve. This high-quality seed layer is found to promote epitaxial growth of Pt/Co50Fe50/Pt trilayers with strong PMA comparable to many repeats of the magnetic multilayers reported previously. In addition, the Pt seed layer enhances the maximum thicknesses of Co50Fe50 that can still maintain PMA up to 1.07 nm.