Abstract We report the effects of implantation-induced-sputtering in determining the true magnetisation of iron nitrides formed by nitrogen implantation into iron films and the changes subsequently observed in their magnetic anisotropy. Iron thin films (40 nm) capped with gold layers were synthesized by ion beam sputtering. Nitrogen was implanted onto the thin film to a dose of 7 × 1016 cm-2. Dynamic ion-solid interaction simulations calculate the average nitrogen concentration within the iron thin films to be 13 at.%. Ion beam analysis was used to evaluate the composition and depth profile of the thin films before and after implantation. Cross-sectional transmission electron microscopy helped in identifying the implantation induced effects at the surface and interface of the thin film structure. Magnetisation measurements show that nitrogen implantation enhances the magnetisation of thin films and reduces their in-plane magnetic anisotropy. High resolution TEM and magnetisation results suggest formation of α’/α”-Fe16N2 with large magnetic moments and perpendicular magnetic anisotropy. The enhancement in magnetisation of the thin film with and without considering the sputtering losses is determined to be 15% and 5%, respectively. Our review of literature shows that underestimating the sputtering losses from implantation leads to reporting of inconsistent and reduced magnetic moments for Fe16N2.

中文翻译：

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离子束合成氮化铁的磁化和磁各向异性

摘要 我们报告了注入诱导溅射在确定通过氮注入铁膜形成的氮化铁的真实磁化强度以及随后观察到的磁各向异性变化方面的影响。通过离子束溅射合成覆盖有金层的铁薄膜（40 nm）。将氮以 7 × 1016 cm-2 的剂量注入到薄膜上。动态离子-固体相互作用模拟计算出铁薄膜内的平均氮浓度为 13 at.%。离子束分析用于评估植入前后薄膜的成分和深度分布。横截面透射电子显微镜有助于识别薄膜结构表面和界面处的注入诱导效应。磁化测量表明，氮注入增强了薄膜的磁化强度并降低了它们的面内磁各向异性。高分辨率 TEM 和磁化结果表明形成了具有大磁矩和垂直磁各向异性的 α'/α”-Fe16N2。在考虑和不考虑溅射损失的情况下，薄膜磁化强度的增强分别确定为 15% 和 5%。我们对文献的回顾表明，低估注入的溅射损失会导致报告 Fe16N2 的磁矩不一致和降低。在考虑和不考虑溅射损失的情况下，薄膜磁化强度的增强分别确定为 15% 和 5%。我们对文献的回顾表明，低估注入的溅射损失会导致报告 Fe16N2 的磁矩不一致和降低。在考虑和不考虑溅射损失的情况下，薄膜磁化强度的增强分别确定为 15% 和 5%。我们对文献的回顾表明，低估注入的溅射损失会导致报告 Fe16N2 的磁矩不一致和降低。