Ordering of island-like FePt crystallites with orientations
Ordering of island-like FePt crystallites with orientations
复制标题
岛状 FePt 微晶的定向有序化
DOI：
10.1063/1.125429
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发表时间：
1999
影响因子：
4
通讯作者：
A. Makino
中科院分区：
文献类型：
--
作者：
B. Bian;Kazuhisa Sato;Y. Hirotsu;A. Makino
制备了由非晶 (a-)Al2O3 分隔的 L10 FePt 定向岛状微晶薄膜。该工艺利用了在 (100) NaCl 和 MgO 衬底上外延生长的 Pt“种子”颗粒上 α-Fe 的过度生长，以及在高于 500°C 的温度下退火时 Fe 和 Pt 之间的有序反应。退火（600°C，6 h）a-Al2O3/Fe（1nm）/Pt（1.5 nm）薄膜在 NaCl（100）和 MgO（100）衬底上的矫顽力均高于 3.3 kOe。透射电镜观察表明，薄膜由取向的L10 FePt岛状晶体组成，平均尺寸为12 nm，间距为4 nm。研究发现，面心立方Pt母粒的三个<100>轴中的任何一个都可以作为L10 FePt超结构的四方c轴，并且四方L10相的所有三变有序晶域都可以存在于10 nm尺寸的FePt小微晶中。薄膜具有高磁矫顽力，且 FePt 颗粒分离良好...
Thin films of oriented island-like crystallites of L10 FePt separated by amorphous (a-)Al2O3 were fabricated. The process took advantage of the overgrowth of α-Fe on Pt “seed” particles epitaxially grown on (100) NaCl and MgO substrates and the ordering reaction between Fe and Pt upon annealing at temperatures higher than 500 °C. The coercivities of the annealed (600 °C for 6 h) a-Al2O3/Fe(1 nm)/Pt (1.5 nm) films on both the NaCl (100) and MgO (100) substrates are higher than 3.3 kOe. Transmission electron microscopy observation showed that the film consisted of oriented L10 FePt island-like crystals with an average size of 12 nm and a separation of 4 nm. It was found that any one of the three 〈100〉 axes of the fcc Pt parent particles could act as the tetragonal c axis of the L10 FePt superstructure and all three-variant ordered crystalline domains of the tetragonal L10 phase could exist in the small 10-nm-size FePt crystallites. The high magnetic coercivity of the film, with well-separated FePt particles...