MgO缓冲层对Si衬底上制备Fe_3Si薄膜性能的影响

Effect of MgO Buffer Layers on Properties of Fe_3Si Thin Films Prepared on Si Substrates

采用磁控溅射方法和热加工工艺在n型Si衬底上溅射不同厚度的MgO层并制备Fe-Si薄膜层,退火后形成Fe_3Si/MgO/Si多层膜结构。利用MgO缓冲层对退火时Si衬底扩散原子进行屏蔽,并分析MgO层对Fe_3Si薄膜结构和电学性质的影响。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和四探针测试仪对Fe_3Si薄膜的晶体结构、表面形貌、断面形貌和电阻率进行表征与分析。研究结果表明:当MgO层厚度为20 nm时生成Fe_(0.9)Si_(0.1)薄膜,当厚度为50,100,150和200 nm时都生成了Fe_3Si薄膜,生成的Fe_3Si和Fe_(0.9)Si_(0.1)薄膜以(110)和(211)取向为主。随MgO缓冲层厚度增加,Si衬底扩散原子对Fe_3Si薄膜的影响减小,Fe_3Si薄膜的晶格常数逐渐减小,晶粒大小趋向均匀,平均电阻率呈现先增大后减小趋势。研究结果为后续基于Fe_3Si薄膜的器件设计与制备提供了参考。

The Fe-Si thin film layer with the sputtered MgO buffer layer with different thicknesses were prepared on the n-type Si substrates by magnetron sputtering method and heat processing technology.The Fe_3Si/MgO/Si multilayer films structure was formed after annealing.MgO buffer layer was used to shield Si substrate diffusion atoms during annealing and the effects of MgO layer on the structure and electrical properties of Fe_3Si thin films were analyzed.The crystal structure,surface morphology,cross-sectional morphology and electrical property of the Fe_3Si thin films were characterized and analyzed by X-ray diffractometer（ XRD）,scanning electron microscope（ SEM） and four-point probe tester.The research results show that the Fe_（0.9）Si_（0.1） thin film forms when the thickness of MgO buffer layer is 20 nm,and the Fe_3Si thin films forms when the thicknesses of MgO buffer layer are 50,100,150 and 200 nm.The generated Fe_3Si and Fe_（0.9）Si_（0.1） thin films have two preferred orientations of（ 110） and（ 211）.With the increase of MgO buffer layer thickness,the effect of Si substrate diffusion atoms on Fe_3Si thin film decreases the lattice constant of the Fe_3Si thin film decreases gradually,the grain size tends to be uniform,and the average resistivity of the Fe_3Si thin film increases first and then decreases.The research results provide areference for the design and preparation of the devices based on the Fe_3Si thin film.