低相变温度垂直取向的CoPtCu/Ag纳米复合膜

采用磁控溅射(Ag/Cu/CoPt)_n多层膜先驱体结合真空退火的方法制备了一系列CoPtCu/Ag纳米复合薄膜，通过优化薄膜中Ag以及Cu的含量，成功制备出了低相变温度垂直取向的CoPtCu/Ag纳米复合膜，该膜在450℃退火即可发生相变，该温度比目前所报导的CoPtAg纳米复合膜的相变温度降低了150℃. 实验结果表明，薄膜中一定含量的Ag元素能够有效诱导薄膜的(001)取向，Cu元素的加入能有效降低薄膜的有序化温度. 对于特定组分为Co₄₀Pt₃₆Cu₈Ag₁₆的薄膜，经500℃退火后已经显示了明显的(001)取向，垂直于膜面方向上的矫顽力为5.0×10⁵A/m，并且薄膜中晶粒尺寸仅为4—5nm，为将来CoPt-L1₀有序相合金薄膜用于超高密度垂直磁记录介质打下了基础.关键词：磁记录材料CoPt纳米复合膜

Low-temperature ordered CoPtCu/Ag nanocomposite film with (001) texture

CoPtCu/Ag nanocomposite films have been prepared using CoPt/Cu/Ag multilayer precursor by magnetron sputtering and subsequent vacuum thermal annealing. Low-temperature ordered CoPtCu/Ag nanocomposite films with (001) texture have been prepared successfully with the optimized content of Ag and Cu in the films. The CoPtCu/Ag films start ordering at a low annealing temperature of 450℃, which is roughly lower by 150℃ than that needed for most CoPt-based films. Our present study shows that the Ag plays a dominant role in inducing the (001) texture of the film and the Cu additive is very effective to reduce the ordering temperature in CoPtAg system. The Co₄₀Pt₃₆Cu₈Ag₁₆ film after annealing at 500℃ exhibits a large perpendicular coercivity of 5.0×10⁵ A/m with a small average grains size of 4—5 nm, implying the potential of the films as future ultrahigh density magnetic recording media.