ABSTRACT

Co1–xTix (x = 0.3, 0.5 and 0.7) thin films were prepared on Si (100) substrate using DC-magnetron sputtering deposition technique. A structural phase transition occurs from hexagonal to cubic crystal structure when the Ti composition is above 30 percentage. The thickness of the films obtained from X-ray Reflectivity data is about 30 nm. The average particle size of the CoTi thin films was calculated using the Atomic Force Microscopy image. The Magneto-Optic Kerr Effect measurements suggest that only Co_0.7Ti_0.3 thin film exhibits soft magnetic behaviour whereas the other thin films have no magnetic properties because of small grain size and reduction of inter-grain exchange interaction. Co_0.7Ti_0.3 thin film has twofold magnetic anisotropy. The angle-dependent coercivity (H_c) is numerically fitted with a two-phase model of magnetization reversal, which confirms the presence of magnetic anisotropy. The magnetization reversal occurs via coherent rotation of spins along the hard axis.

摘要

Co1–xTix (x = 0.3, 0.5 和 0.7) 薄膜使用直流磁控溅射沉积技术在 Si (100) 衬底上制备。当 Ti 成分高于 30% 时，结构相变发生从六方晶体结构到立方晶体结构。从 X 射线反射率数据获得的薄膜厚度约为 30 nm。使用原子力显微镜图像计算 CoTi 薄膜的平均粒径。磁光克尔效应测量表明，只有 Co _0.7 Ti _0.3薄膜表现出软磁行为，而其他薄膜由于晶粒尺寸小和晶粒间交换相互作用的减少而没有磁性。钴_0.7钛_0.3薄膜具有双重磁各向异性。与角度相关的矫顽力 ( H _c ) 在数值上符合磁化反转的两相模型，这证实了磁各向异性的存在。磁化反转通过自旋沿难轴的相干旋转发生。