Si3N4/FePd/Si3N4薄膜的晶体结构和磁性能研究

采用磁控溅射的方法制备了Si₃N₄/FePd/Si₃N₄三层膜, 研究了非磁性材料Si₃N₄作为插入层对磁记录FePd薄膜结构与磁性能的影响。结果表明, 热处理后Si₃N₄分布在FePd纳米颗粒之间, 抑制了FePd晶粒的生长, 与纯FePd薄膜相比, Si₃N₄/FePd/Si₃N₄薄膜的颗粒明显得到细化; 通过添加Si₃N₄层, FePd薄膜的晶体学参数c/a从0.960减小到0.946, 表明Si₃N₄可以有效促进FePd薄膜的有序化进程, 同时提升了矫顽力和剩磁比, 分别提高到249 kA/m、0.86; 随着600℃退火时间的进一步延长, 添加Si₃N₄的薄膜磁性没有迅速下降, 在较宽的热处理时间范围内磁性能保持在比较高的水平, 提高了抗热影响的能力。Si₃N₄作为插入层对FePd薄膜的磁性能具有较大的提升作用, 这对磁记录薄膜的发展具有重要意义。

Crystal Structure and Magnetic Property of Si3N4/FePd/Si3N4 Thin Films

Si₃N₄/FePd/Si₃N₄ trilayer films were prepared by magnetron sputtering. The effect of Si₃N₄ insert as a non-magnetic material on structure and magnetic properties of FePd films was investigated. The results show that Si₃N₄ particles distribute between the FePd nanoparticles after heat treatment, which inhibit the growth of FePd grains. Compared with pure FePd films, the grains of Si₃N₄/FePd /Si₃N₄ thin films are obviously refined. By adding Si₃N₄ insert, the crystallographic parameters c/a of FePd films decrease from 0.960 to 0.946, indicating that Si₃N₄ content could effectively promote the ordering process of FePd films and improve the coercivity and remanence ratio. The coercivity and remanence ratio are increased to 249 kA/m and 0.86, respectively. With the further increase of the annealing time at 600℃, the magnetic property of the Si₃N₄-doped FePd thin films does not decrease rapidly, and its relatively high magnetic properties maintain over a wide range of annealing time, which indicate that the thermal resistance of FePd thin films are obviously improved. Si₃N₄ insert plays a great role in promoting the magnetic properties of FePd thin films, which is significant for the development of magnetic recording film materials.