Hattori Takuma, Kawamura Norikazu, Iimori Takushi, Miyamachi Toshio, Komori Fumio
Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan.
Nano Lett. 2021 Mar 24;21(6):2406-2411. doi: 10.1021/acs.nanolett.0c04408. Epub 2021 Mar 9.
Mapping of the local lattice distortion is required to understand the details of the chemical and physical properties of thin films. However, the resolution by the direct microscopic methods was insufficient to detect the local distortion. Here, we have demonstrated that the local distortion of a monatomic film on a substrate is estimated with high resolution using the moiré pattern of the topographic scanning tunneling microscopy image. The analysis focused on the apparently low centers of the moiré pattern of the hexagonal iron nitride monolayer on the Cu(111) substrate. The local distortion was visualized by estimating the displacement of the experimentally detected center position from the ideal position that is extracted from the adjacent center positions. The map of the local distortion revealed that the subsurface impurities are preferentially located on the largely distorted areas. This approach is widely applicable to other thin films on the substrates.
为了理解薄膜化学和物理性质的细节，需要对局部晶格畸变进行映射。然而，直接显微镜方法的分辨率不足以检测局部畸变。在这里，我们已经证明，利用形貌扫描隧道显微镜图像的莫尔条纹图案，可以高分辨率地估计衬底上单原子薄膜的局部畸变。分析聚焦于Cu(111)衬底上六方氮化铁单层莫尔条纹图案明显较低的中心。通过估计实验检测到的中心位置相对于从相邻中心位置提取的理想位置的位移，使局部畸变可视化。局部畸变图显示，亚表面杂质优先位于畸变较大的区域。这种方法广泛适用于衬底上的其他薄膜。
