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用直流磁控溅射法在Si(001) 衬底上制备了以Ta 为缓冲层、含有15 周期的Ni80Fe20(4nm)/Cu(6 nm) 多层膜.样品分别在150 ,250 ,350 ℃进行了真空退火处理.用低角和高角X 射线衍射法研究了多层膜的微结构.结果表明,所有样品均有较好的[111] 取向,而且随退火温度或时间的增加,[111] 取向程度变得更高.超晶格周期、平均面间距在退火后略有减小,表明多层膜结构在退火后变得更为致密.多层膜界面粗糙度随退火温度或时间的增加而增大,平均相关长度随退火温度或时间的增加而减小,分析认为这是由于Ni80Fe20/Cu 界面存在严重的互扩散所导致的.模拟Ni80Fe20/Cu 多层膜高角X 射线衍射谱,发现在Ni80Fe20/Cu 界面有非常厚的混合层存在,而且混合层厚度随退火温度或时间的增加而增大.模拟结果还表明,随退火温度或时间的增加,Ni80Fe20 层面间距几乎保持不变,Cu 层面间距则随退火温度的增加而略有减小.
A 15 - cycle Ni80Fe20 (4nm) / Cu (6nm) multilayers were fabricated on Si (001) substrates by DC magnetron sputtering. The samples were vacuum annealed at 150, 250 and 350 ℃, respectively. The microstructures of multilayer films were investigated by low-angle and high-angle X-ray diffraction. The results show that all the samples have better [111] orientation, and the orientation of [111] becomes higher as the annealing temperature or time increases. The superlattice period and average interplanar spacing decreased slightly after annealing, indicating that the multilayer structure became denser after annealing. The interfacial roughness increases with the increase of annealing temperature or time, and the average correlation length decreases with the increase of annealing temperature or time. This is attributed to the serious interdiffusion of Ni80Fe20 / Cu interface. The high-angle X-ray diffraction spectra of Ni80Fe20 / Cu multilayers were simulated and found to have a very thick mixed layer at the Ni80Fe20 / Cu interface, and the thickness of the mixed layer increased with annealing temperature or time. The simulation results also show that as the annealing temperature or time increases, the Ni80Fe20 layer spacing remains almost unchanged, while the Cu layer spacing decreases slightly with increasing annealing temperature.