Sputtered L 1 0 ‐FePd and its Synthetic Antiferromagnet on Si/SiO 2 Wafers for Scalable Spintronics

As a promising alternative to the mainstream CoFeB/MgO system with interfacial perpendicular magnetic anisotropy (PMA), L 1 0 ‐FePd and its synthetic antiferromagnet (SAF) structure with large crystalline PMA can support spintronic devices with sufficient thermal stability at sub‐5 nm sizes. However, the compatibility requirement of preparing L 1 0 ‐FePd thin films on Si/SiO 2 wafers is still unmet. In this paper, high‐quality L 1 0 ‐FePd and its SAF on Si/SiO 2 wafers are prepared by coating the amorphous SiO 2 surface with an MgO(001) seed layer. The prepared L 1 0 ‐FePd single layer and SAF stack are highly (001)‐textured, showing strong PMA, low damping, and sizeable interlayer exchange coupling, respectively. Systematic characterizations, including advanced X‐ray diffraction measurement and atomic resolution‐scanning transmission electron microscopy, are conducted to explain the outstanding performance of L 1 0 ‐FePd layers. A fully‐epitaxial growth that starts from MgO seed layer, induces the (001) texture of L 1 0 ‐FePd, and extends through the SAF spacer is observed. This study makes the vision of scalable spintronics more practical.