Sputtered L10‐FePd and its Synthetic Antiferromagnet on Si/SiO2 Wafers for Scalable Spintronics

As a promising alternative to the mainstream CoFeB/MgO system with interfacial perpendicular magnetic anisotropy (PMA), L10‐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 L10‐FePd thin films on Si/SiO2 wafers is still unmet. In this paper, high‐quality L10‐FePd and its SAF on Si/SiO2 wafers are prepared by coating the amorphous SiO2 surface with an MgO(001) seed layer. The prepared L10‐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 L10‐FePd layers. A fully‐epitaxial growth that starts from MgO seed layer, induces the (001) texture of L10‐FePd, and extends through the SAF spacer is observed. This study makes the vision of scalable spintronics more practical. In this study, high‐quality L10‐FePd thin films are prepared with large perpendicular magnetic anisotropy and low damping on industry‐ready Si/SiO2 wafers using an MgO(001) seed layer. Further, L10‐FePd/Ir/L10‐FePd perpendicularly magnetized synthetic antiferromagnets are fabricated on Si/SiO2 wafers and strong antiferromagnetic interlayer exchange coupling is reported. The heteroepitaxial growth of thin films is characterized comprehensively.