Department of Electrical and Computer Engineering, National University of Singapore, Singapore.
Sci Rep. 2013;3:1907. doi: 10.1038/srep01907.
Ion implantation is a promising technique for fabricating high density bit patterned media (BPM) as it may eliminate the requirement of disk planarization. However, there has not been any notable study on the impact of implantation on BPM fabrication of FePt, particularly at nano-scale, where the lateral straggle of implanted ions may become comparable to the feature size. In this work, implantation of antimony ions in patterned and unpatterned L1(0)-FePt thin films has been investigated. Unpatterned films implanted with high fluence of antimony exhibited reduced out-of-plane coercivity and change of magnetic anisotropy from perpendicular direction to film-plane. Interestingly, for samples implanted through patterned masks, the perpendicular anisotropy in the unimplanted region was also lost. This noteworthy observation can be attributed to the displacement of Fe and Pt atoms from the implantation sites to the unimplanted areas, thereby causing a phase disorder transformation from L1(0) to A1 FePt.
离子注入是制备高密度位图案介质（BPM）的一种很有前途的技术，因为它可能消除磁盘平面化的要求。然而，对于注入离子对 FePt 的 BPM 制备的影响，特别是在纳米尺度上，注入离子的横向离散度可能与特征尺寸相当，还没有任何显著的研究。在这项工作中，研究了图案化和非图案化 L1(0)-FePt 薄膜中的锑离子注入。高剂量锑注入的非图案化薄膜表现出面外矫顽力降低和磁各向异性从垂直方向到薄膜平面的变化。有趣的是，对于通过图案化掩模注入的样品，未注入区域的垂直各向异性也消失了。这一值得注意的观察结果可以归因于 Fe 和 Pt 原子从注入位置到未注入区域的位移，从而导致从 L1(0)到 A1 FePt 的相无序转变。
