Mn_xGe_(1-x)稀磁半导体薄膜的结构研究  

Structure of Mn_xGe_(1-x) dilute magnetic semiconductor films

作　　者：孙玉[1,2] 孙治湖[1] 朱三元[1,2] 史同飞[1,2] 叶剑[1] 潘志云[1] 刘文汉[3] 韦世强[1] 

机构地区：[1]中国科学技术大学国家同步辐射实验室 [2]中国科学技术大学物理系,合肥230026 [3]中国科学技术大学物理系

出　　处：《物理学报》2007年第9期5471-5475,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10404023;10635060)资助的课题.~~

摘　　要：利用X射线衍射(XRD)和X射线吸收精细结构(XAFS)方法研究了磁控共溅射方法制备的MnxGe1-x薄膜样品的结构随掺杂磁性原子Mn含量的变化规律.XRD结果表明,在Mn的含量较低(7.0%)的Mn0.07Ge0.93样品中,只能观察到对应于多晶Ge的XRD衍射峰,而对Mn含量较高(25.0%,36.0%)的Mn0.25Ge0.75和Mn0.36Ge0.64样品则明显出现Ge3Mn5相的衍射峰,且Ge3Mn5的比例随着Mn的含量升高而增加.XAFS结果表明,对于Mn0.07Ge0.93样品,Mn主要以替代位的形式存在,占75%左右的比例;在Mn0.25Ge0.75和Mn0.36Ge0.64的样品中,除了一小部分的Mn原子以替代位的形式存在之外,大部分Mn原子以Ge3Mn5化合物的形式存在.The structure of MnxGe1-x dilute magnetic semiconductor thin films prepared by magnetron co-sputtering has been studied by X-ray diffraction （XRD） and X-ray absorption fine structure （XAFS） techniques. The XRD results show that in the MnxGe 1-x thin film with low Mn doping concentration （x=0.070）, only diffraction peaks attributed to crystalline Ge can be observed. In samples with high Mn doping concentrations （x=0.250, 0.360）, the secondary phase Ge3Mn5 appears, and its content enhances with Mn doping concentration. The XAFS results indicate that for the Mn 0.07 Ge 0.93 thin film, Mn atoms are mainly incorporated into the Ge lattice and located at the substitutional sites of Ge atoms with the ratio of 75%, while for the Mn 0.25 Ge 0.75 and Mn 0.36 Ge 0.64 samples, most of the Mn atoms are aggregated to form Ge3Mn5.

关 键 词：磁控溅射 XRD XAFS MnxGe1-x稀磁半导体薄膜 

分 类 号：O471[理学—半导体物理] O484[理学—物理]