室温生长MgO底层诱导(001)取向FePt薄膜的有序化过程对FePt成分的依赖

室温下通过磁控溅射在表面热氧化的Si基片上生长了MgO/Fe_xPt_100-x双层膜和Fe_xPt_100-x单层膜系列样品，Fe_xPt_100-x的原子成分x=48—68.研究了热处理前后不同成分FePt薄膜的晶体结构和磁性的变化，尤其是MgO底层的引入对FePt的晶体结构和磁性的影响 关键词： FePt(001)薄膜 0相')" href="#">L1₀相

Composition dependence of L10 ordering of FePt (001) thin films on MgO underlayer grown at room temperature

We investigated the effect of extensive compositional change on the structure and magnetic properties of the post-annealed Fe_xPt_100-x (48≤x≤68) thin films with and without MgO underlayer deposited at room temperature. It was found that, during annealing, the FePt films on MgO underlayer with Fe-rich composition around 59at% exhibit much faster ordering than those with other compositions although the single layer FePt films were found to have the optimum composition for the chemical ordering of only slightly Fe-rich composition of 52at% of Fe. The film of MgO(10 nm)/Fe₅₉Pt₄₁(8 nm) after annealing at 600℃ for 30 min showed perpendicular magnetization with coercivity about 800 kA/m and the squareness was close to 1 due to the formation of (001) oriented ordering phase. The results of FePt thin films on MgO underlayer deposited at room temperature present a striking contrast with those of FePt grown on heated MgO single crystal substrate, where the optimum composition for the ordering was around 62at% of Pt. An interpretation on the observed experimental phenomena is given in this paper.